'Tenting' stitches for the scalp.

'Tenting' stitches for the scalp. A subgaleal collection of blood or cerebrospinal fluid (CSF) is commonly encountered after craniotomy. In spite of the placement of subgaleal drains by many neurosurgeons, a collection at this site is frequent and occasionally can result in complications. 'Tenting' scalp stitches are described. Three to four (or more) stitches are inserted between the galea and the pericranium or between the pericranium and the craniotomy flap at the end of the surgical procedure. This simple manoeuvre was seen significantly to reduce collections in these spaces. To our knowledge, this technique has not been reported in the neurosurgical literature, and we strongly advocate its use.


Chronic extradural haematomas: indications for surgery. Non-invasive neuro-imaging has led to the detection of minimally symptomatic or asymptomatic chronic extradural haematomas. Our experience and review of the literature suggests that, as in the case of chronic subdural haematomas, there is development of membranes and liquifaction of the clot which may permit drainage of such collections through twist drill or burrholes. The time from development and the neuro-imaging chanes on CT and MRI can suggest the age and nature of the clot and thus permit timing of surgery so that drainage may be accomplished with a minor procedure.


Cysticercosis producing various neurological presentations in a patient: case report. We present an unusual case of neurocysticercosis supported by characteristic lesions on computed tomography and positive serum and CSF titres. The patient came to medical attention on various occasions over a decade with three clearly separate neurological presentations (acute psychosis, cerebral infarction, and hydrocephalus) before diagnosis was made.


Oligodendroglioma of the fourth ventricle with intracranial and spinal oligodendrogliomatosis: a case report. We report a case of oligodendroglioma of the fourth ventricle complicated by disseminated intracranial and spinal oligodendrogliomatosis. This is further evidence that primary oligodendrogliomas arising in close proximity to the cerebrospinal pathway have a predilection for spontaneous dissemination. This condition should be considered in the differential diagnosis of hydrocephalus and myelopathy.


Functional recovery after near complete traumatic deficit of the cervical cord lasting more than 24 h. Two young men presented with a complete cervical cord deficit associated with bilateral C4-C5 dislocation and 11 mm encroachment (sagittal narrowing) of the spinal canal in one case and near complete cervical cord deficit due to a crush fracture of the C7 vertebral body with 9 mm axial compression and 50% antero-posterior encroachment of the canal in the other case. There was no improvement within the first 24 h. Both patients left the hospital walking after open surgical realignment and complete cord decompression.


An 'empty' sphenoid mucocele.

An 'empty' sphenoid mucocele. Sphenoid sinus mucoceles behave as mass lesions producing erosion of adjacent bone and cranial nerve palsies. The probable cause is obstruction of the ostia of the sinus. We describe a case which was 'cured' inadvertently by a nasal polypectomy.


Hypothermia due to transient hypothalamic dysfunction in tuberculous meningitis with hydrocephalus. We report two patients with tuberculous meningitis and hydrocephalus who developed hypothermia that reversed after inserting a ventricular shunt for the hydrocephalus. Pressure on the thermoregulatory centre in the posterior hypothalamus near the dilated third ventricle might have been responsible. One patient developed hypotension during the transient hypothermia, which persisted and proved fatal.


Cholera as a model for research on mucosal immunity and development of oral vaccines. During the past year, the extensive investigational use of a recently developed oral vaccine against cholera has led to significant advances in our understanding of both immunity to cholera and related diarrhoeal diseases, and the mucosal immune response in general after oral immunization. The oral cholera vaccine has been shown to protect, through its cholera toxin B subunit component, against travellers' diarrhoea caused by enterotoxigenic Escherichia coli. The elaboration of sensitive new techniques has allowed detailed clonal analyses of the activation of specific B and T cells and immunologic memory in intestinal mucosa in humans after oral cholera vaccination. These techniques have also been used to demonstrate a transient appearance after immunization of specific gut-derived IgA antibody-producing cells in the circulation and also, a few days later, in a distant mucosal tissue such as the salivary glands.


Superantigens.

Superantigens. The endogenous superantigens (the enigmatic minor lymphocyte-stimulating antigens) have been identified; they are encoded by integrated mouse mammary tumor viruses. The retroviral superantigens appear to be transmembrane glycoproteins, and their highly variable extracellular carboxyl terminus is responsible for V beta interaction. In spite of intensive efforts the precise structure-function relationship for the superantigens is not yet clear. The most important consequences of the introduction of the superantigens in vivo are shock and T-cell depletion and anergy. The search for novel superantigens related to human diseases has started.


Heat-shock proteins: immunity and autoimmunity. Antigens from a wide variety of pathogens have been identified as members of conserved heat-shock protein families, sharing upwards of 50% amino acid identity with corresponding host-cell proteins. Analysis of the responses to these conserved antigens may provide insights into regulation of the immune system during infection and autoimmunity.


Antigen presentation in virus infection. Important recent advances have been made in our understanding of antigen processing of cytoplasmic antigens and presentation by class I molecules of the MHC. Peptide transporter-like molecules encoded within the MHC have been characterized and have, by transfection, corrected some of the presentation-mutant cell lines. The nature of peptide-MHC class I interactions has been clarified by further resolution of the HLA A2 and B27 crystals and elution of peptides. The differences between antigenicity and immunogenicity for viral antigens have been highlighted by studies in transgenic animals.


Virally induced immunosuppression.

Virally induced immunosuppression. A mouse model of virus-triggered, T-cell mediated acquired immunosuppression is analyzed. Lymphocytic choriomeningitis virus initially infects mostly macrophages and antigen-presenting cells; these are destroyed by lymphocytic choriomeningitis virus specific cytotoxic T cells resulting in immunosuppression. Similar immunopathological mechanisms may play a role in acquired immune deficiency syndrome.


Immunity to schistosomes.

Immunity to schistosomes. Significant advances have been made during the past years in our knowledge of schistosomiasis, the second major parasitic disease in the world. The highlights provide a good illustration of the recent progress made in our understanding of immunity in human populations and the regulation of the immune response, and in the approach toward a vaccine.


Malaria: becoming more specific about non-specific immunity. For the hundreds of millions of people presently infected with malaria, survival may depend on relatively non-specific immune effector mechanisms. Progress has been made in understanding the anti-parasitic properties of tumor necrosis factor-alpha, interferon-gamma and nitric oxide, in defining the parasite toxins that induce tumor necrosis factor-alpha production, and in exploring the role of cytokines and adhesion molecules in the pathogenesis of cerebral malaria.


Malaria vaccines.

Malaria vaccines. The development of an effective malaria vaccine is a feasible goal. Most of the vaccines being developed today are subunit vaccines derived from selected parasite antigens or their immunologically active fragments. The precise characterization of protective immune responses against Plasmodium parasites remains a fundamental part of present research aimed at obtaining a malaria vaccine(s).


Old microbes with new faces: molecular biology and the design of new vaccines. Rational approaches to the design of live attenuated bacterial and viral recombinant vaccine strains are leading to the manipulation of old vaccines and the generation of new ones. The two basic problems to be solved are attenuation of pathogenic strains, and the stable expression of foreign antigens.


New carriers and adjuvants in the development of vaccines. Different approaches are being followed to enhance the immunogenicity of established and newly developed vaccines. Some of them foresee the utilization of carrier molecules recognized by the immune systems of a large proportion of the human population. Others are directed mainly towards the development of improved adjuvants and delivery systems.


Cellular latency of human immunodeficiency virus type 1. The infection of humans by human immunodeficiency virus type 1 is characterized by a prolonged stage of clinical quiescence. This clinically asymptomatic period may be based, in part, on the development of cell populations within the body that maintain human immunodeficiency virus type 1 in a state of latency. Recent advances in the understanding of the molecular mechanisms involved in various forms of cellular latency of human immunodeficiency virus type 1 have begun to shed light on the variable period of asymptomatic infection. The elucidation of cellular retroviral latency, in vivo, will also be critical to the design of novel therapeutic approaches with which to combat human immunodeficiency virus type 1 infections.


Genetic immunodeficiencies: both the lumpers and the splitters can claim victory. Over the last few years, molecular approaches to analysis of genetic immunodeficiencies have made it clear that different mutations of the same gene may result in very different clinical presentations. On the other hand, a single clinical syndrome is sometimes due to mutations in a variety of independent genes. In the future, appropriate treatment, particularly gene therapy, will depend on a precise genetic diagnosis.


Social and emotional patterns in adulthood: support for socioemotional selectivity theory. This investigation explored 2 hypotheses derived from socioemotional selectivity theory: (a) Selective reductions in social interaction begin in early adulthood and (b) emotional closeness to significant others increases rather than decreases in adulthood even when rate reductions occur. Transcribed interviews with 28 women and 22 men from the Child Guidance Study, conducted over 34 years, were reviewed and rated for frequency of interaction, satisfaction with the relationship, and degree of emotional closeness in 6 types of relationships. Interaction frequency with acquaintances and close friends declined from early adulthood on. Interaction frequency with spouses and siblings increased across the same time period and emotional closeness increased throughout adulthood in relationships with relatives and close friends. Findings suggest that individuals begin narrowing their range of social partners long before old age.


Age and visual field differences in computing visual-spatial relations. Age and brain hemispheric differences in visual-spatial performance were investigated using 2 versions of categorical and coordinate (metric) spatial relations tasks. Thirty-two young adults (M = 19.2 years) and 32 older adults (M = 68.8 years) participated. An overall age-related decrement in computing visual-spatial relations was obtained for lateralized presentations and when items were presented centrally. In contrast to some previous findings, there was no evidence to suggest differential aging of the right hemisphere in computing visual-spatial relations.


Physical illness and symptoms of depression among elderly outpatients. Elderly outpatients were assessed to clarify relations between symptoms of depression and physical illness, disability, pain, and selected psychosocial variables. Three types of assessments were made: (a) medical evaluations by physicians, (b) self-reported symptoms of depression and physical health, and (c) demographic and psychosocial data relating to participants' life circumstances. Both objective (physician-rated illness symptoms) and subjective (self-reported health, activity restriction, and use of pain medications) indicators of health accounted for independent variance in symptoms of depression. After controlling for these factors, additional variance was explained by health-related concerns (e.g., health care expenses, service needs), social support, and "other worries" (e.g., feeling useless, becoming a burden to others).


Age-related differences in memory as a function of imagery processing. The effects of aging on imagery production and use--following the learning of concrete and abstract words--and their relations to subsequent memory performance were explored in 2 experiments. Both experiments demonstrated better free recall of concrete than of abstract words (the concreteness effect). Experiment 1 showed this superiority to be greater for young subjects only under explicit imagery instructions. Experiment 2 revealed that the advantage of concrete over abstract words reflects the use of differential imagery production. The results are discussed in terms of age differences in imagery utilization and the effects of visual processing on recall.


Category knowledge in Alzheimer's disease: normal organization and a general retrieval deficit. Three hypotheses that could account for deficits in the retrieval of category information in Alzheimer's disease (AD) were evaluated: abnormal organization, class- or category-specific vulnerability, and limitation by general factors, such as decreased processing speed. Relative to 18 elderly control subjects, 18 patients with AD produced fewer items in a category fluency task and had longer reaction times in a category decision task. The pattern of performance across categories on both tasks was normal in the AD group: The same categories elicited the most (or fastest) responses in both the control group and the AD group. AD patients showed normal performance in ranking of category exemplars by typicality. There was no evidence for differential accessibility by category or by class of information (animate vs. inanimate). The authors conclude that a general factor or factors limit(s) retrievability equally across all categories.


Mental and physical health of spouse caregivers: the role of personality. Although personal resources of caregivers, such as coping skills and social support, have been shown to be important in understanding caregiver stress and health outcomes, personality traits have not previously been considered. The purpose of this study was to examine the association between the personality traits of neuroticism and dispositional optimism and mental and physical health outcomes. It was predicted that personality would have direct effects, and indirect effects through perceived stress, on health outcomes. Participants were spouse caregivers of patients diagnosed with Alzheimer's disease. Results showed that neuroticism and optimism were significantly related to mental and physical health. Furthermore, neuroticism had significant direct effects on all of the health outcomes, and substantial indirect effects, through perceived stress, on mental health outcomes. Optimism showed stronger indirect than direct effects on all health outcomes. These findings demonstrate the importance of including personality of the caregiver in theoretical and empirical models of the caregiving process.


Aging, expertise, and narrative processing. In a study of how aviation expertise influences age differences in narrative processing, young and older pilots and nonpilots read and recalled aviation and general narratives. They chose referents for sentences referring to a protagonist or minor character mentioned 1 sentence (recent character) or 3 sentences (distant character) before this target sentence. All groups chose referents less accurately for sentences about distant and minor characters than about recent and protagonist characters, perhaps because these referents were less likely to be in working memory. Young readers and pilots were more accurate for distant and minor character target sentences in aviation narratives, and recalled aviation narratives more accurately. Expertise did not reduce age differences. Expertise differences may reflect decreased demands on working memory capacity, and age declines may reflect reduced capacity.


Spatial cognition and neighborhood use: the relationship in older adults. Measures of spatial cognition, neighborhood knowledge, and neighborhood use from the research described by Walsh, Krauss, and Regnier (1981) were examined to determine if laboratory tests of spatial cognition were significant predictors of older adults' use of their neighborhoods. The overall results show that laboratory-based measures of spatial cognition and subjects' knowledge of their neighborhoods are both significant predictors of their use of neighborhood goods and services. The ability to learn and remember the location and orientation of objects, when contextual cues were not provided at test, was more predictive of the participants' neighborhood use than either the participants' number of years in the neighborhood or their mobility. Spatial memory as measured by the Educational Testing Service Building Memory task predicted neighborhood knowledge, which was predictive of neighborhood use.


Communicative function in patients with questionable Alzheimer's disease. The communicative skills of patients with questionable Alzheimer's disease (AD) were examined by having patients describe events shown in a silent video cartoon. As anticipated, questionable AD patients provided fewer clauses in their descriptions than did education- and age-matched controls. This finding was independent of differences in word finding ability. More important, the patients failed to describe as many of the thematically important events as did the controls, a difference that affected the overall informativeness of the communication. Even though the patients were sensitive to event importance, there was no evidence of compensation in their descriptions (i.e., a greater concentration of important events). Several interpretations are presented that focus on possible deficits in the pragmatic or semantic systems of language or both as an early symptom of Alzheimer's disease.


Implicit processing in the cued recall of young and old adults. Two cued recall experiments were reported in which younger and older subjects studied target words varying in number of preexperimental associates. In Experiment 1, targets were studied in either the absence or presence of meaning-related context cues, with recall always prompted by the cues. In the absence of context, words with smaller sets of associates were easier to recall than those with larger sets, but this effect was reduced for older subjects. The presence of a study context cue facilitated recall and eliminated the effect of associative set size for both ages. In Experiment 2, targets were studied and tested in the presence of unrelated words. In this situation, words with smaller sets of associates were less likely to be recalled than words with larger sets; again the effect was reduced for older subjects. The results are interpreted as an age decrement in processing implicitly activated information.


The dependency-support script in institutions: generalization to community settings. This study tested the generalizability of the dependency-support script, a behavioral system describing and explaining dependent behaviors of the institutionalized elderly. A comparative study with 22 community-dwelling elderly was conducted, which identified typical interaction patterns between the elderly and family members or home health nurses. The dominant interaction pattern in the community setting, too, was the dependency-support script. In addition, however, a significant social response to independent self-care behavior was observed, which created a highly ambivalent response contingency. Independent behaviors were followed about twice as often by an incongruent (dependence-supportive) than by a congruent (independence-supportive) response. Expectations of incompetence and of the helping role are offered as explanations.


Progressive and imaginal relaxation training for elderly persons with subjective anxiety. Elders exposed to either progressive or imaginal relaxation procedures reported significant relaxation effects and showed improvement on measures of personal functioning. The results of the Physical Assessment Scale of the Relaxation Inventory indicated that relaxation responses were acquired within and across sessions. Large, consistent changes in relaxation occurred in all 4 sessions. The Symptom Checklist-90-R, which measures self-reported personal adjustment, showed significant positive changes following relaxation training and at 1-month follow-up. Elders who imagined muscle tension release profited as much as those engaged in actual muscle tension-release activities. This finding is of importance for older adults who may experience physical limitations that contraindicate muscle-tension-release procedures.


Skill learning in the elderly: diminished implicit and explicit memory for a motor sequence. Explicit and implicit memory for a cognitive-motor sequence was studied in elderly and young adults. Implicit memory was examined in a serial reaction-time paradigm in which sequences of hand postures repeated cyclically, then shifted to random sequences. Two control groups received random sequences throughout. Movement times (MTs) across the first 4 blocks did not improve more in the elderly-repeated than in the elderly-random group. In contrast, the young-repeated group showed greater improvement in MT across these blocks than the young-random group. MT was less affected in the elderly than in the young by shifts between repeated and random sequences, indicating impaired implicit memory. Explicit memory, which was assessed by free recall and cued recall, also was impaired in the elderly. Diminished implicit memory in the elderly could not be explained solely by the possible intrusion of conscious recollection strategies.


Adult age differences in memory for routes: effects of instruction and spatial diagram. Free-recall and multiple-choice measures of memory for landmarks, sequential order, turns, and route configurations were obtained from younger and older adults after they viewed slides of 2 overlapping routes. Instructions focused attention on either the contents of the slides or on the course of the path; a control condition provided no orientational instructions. Half the subjects viewed maplike diagrams of the joint spatial configuration. Age interacted with instruction only for multiple-choice tests of landmark memory. Age interacted with diagram for each of the other 3 route memory components, although the generality of this interaction across instruction condition depended on whether free-recall or multiple-choice tests were used. The results suggest that route memory may involve both scene and layout representation, which may be differentially sensitive to age and presentational variables.


Age differences in using source-relevant cues. Subjects heard words originating from 2 speakers and later decided which of the 2 speakers said the words. Older adults had difficulty with source monitoring when perceptual cues from 2 sources were similar (2 female speakers), but this difficulty was overcome when perceptual cues were distinctive (a male and a female speaker) and were the only salient cues to source. Older adults also benefited from distinctive spatial cues when these were the only salient cues to source. Older adults, however, experienced difficulties in using multiple cues (both perceptual and spatial) to source effectively, whereas younger adults were able to use multiple cues to enhance their source-monitoring performance. It is suggested that age differences in source monitoring result from differential cue utilization.


Aging and shifts of visual spatial attention. Three experiments examined adult age differences in the efficiency of endogenous (voluntary) and exogenous (involuntary) attention shifts. Younger and older subjects performed a spatial cuing task in which abruptly onset peripheral cues (Experiment 1) or central, symbolic cues (Experiments 2 and 3) were presented before a target stimulus at intervals ranging from 50 to 250 ms. With peripheral cues, the magnitude of cuing effects was at least as great for older as for younger adults and followed a similar time course. Similar results were obtained with symbolic cues, although cuing effects for older adults varied with cue difficulty. The results suggest that cue encoding may decline with advancing age but that the efficiency of the shift process is preserved.


Exercise adherence or maintenance among older adults: 1-year follow-up study. Follow-up evaluation was conducted of 101 older men and women (mean age = 67 +/- 5 years) who had participated in a randomized study of physiological and psychological effects of aerobic exercise. Eighty-five subjects completed the follow-up evaluation, and almost all of them (94%) reported continuing with physical activity, as assessed by a self-report measure. Total energy expenditure was calculated as an indicator of exercise maintenance, and energy expenditure at follow-up was predicted from measures of physiological functioning, psychological well-being, and cognitive functioning obtained at the conclusion of the structured exercise program. Greater cardiorespiratory endurance, faster psychomotor speed, and lower anxiety predicted exercise behavior at follow-up, accounting for 13% of the variance in exercise behavior. Gender was not a significant predictor of exercise behavior.


Age-related deficits in prospective memory: the influence of task complexity. Younger and older subjects were asked to perform an action whenever target words occurred during a short-term memory task. The difficulty of this prospective memory task was manipulated by varying the delay preceding the occurrence of a target event and by varying the number of different target events. Age-related performance differences emerged when there were several different target events but not when there was one target event presented several times. Age-related performance differences, when they occurred, were associated with poorer retrospective memory for the target events. The results were interpreted in terms of a componential analysis of prospective memory, which assumes both similarities and differences between prospective and retrospective memory.


Age and forgetfulness: perceivers' impressions of targets' capability. In a person perception paradigm, 72 young and 72 old adult Ss listened to tape recordings of a nonforgetful, moderately forgetful, or highly forgetful female target person being interviewed for a volunteer job. Ss then rated their opinion of the target's memory and how likely they would be to assign the target to easy and difficult tasks. Overall, Ss gave higher memory opinion ratings to old than to young targets. As expected, they were more likely to assign tasks to nonforgetful than to forgetful targets. However, they were more egalitarian than was hypothesized in their task assignment ratings for forgetful young versus forgetful old targets.


The apprehensive respondent: failing to rate future life satisfaction in older adults. Rating scales relating to the individual's past, present, and future were administered to subjects aged 60 to 90; those who completed all ratings (N = 589) were compared with others who specifically failed to rate the future (N = 150). The groups were differentiated by age, gender, health, and marital status. Total subjective well-being did not differ, but specific subjective well-being factors concerning time and aging could serve as discriminators. These differences suggest that these older adults might be apprehensive about their future, and that skipping future-related questions is a genuine reaction with both psychological and methodological implications.


HIV-1 gp41 contains two sites for interaction with several proteins on the helper T-lymphoid cell line, H9. To characterize putative binding sites for HIV-1 gp41 to H9 cells. Based on accumulating evidence in the literature that HIV-1 can bind to cell surfaces independent of CD4, we attempted to clarify whether gp41, the transmembrane HIV-1 protein, contributes to CD4-independent binding. We therefore tested binding of gp41 to cells. Using fluorescence-activated cell-sorter analysis, we examined the binding of recombinant gp160 (gp160) and soluble gp41 (sgp41; Env amino acids 539-684) to H9 cells, and located the putative binding site(s) of gp41 by inhibition using 16 HIV-1 Env peptides. Putative HIV-1 receptor proteins in H9 cell lysates were Western blotted and precipitated using sgp41. sgp41 bound to the CD4+ H9 cells and rgp160 bound to H9 cells independent of gp120-binding sites on CD4 molecules. Two gp41 peptides (Env amino acids 591-605 and 651-665) inhibited the binding of sgp41 to H9 cells. Four bands, of 37, 40, 55 and 97 kD, were blotted in H9 cell lysates, and three bands, 40, 97 and 108 kD, were observed in the precipitation analysis using lysates of 125I-surface-labelled H9 cells and sgp41 attached to sepharose beads. HIV-1 gp41 contains two putative binding sites to H9 cells. These sites may be located within Env amino acids 591-605 (ERYLKDQQLLGIWGC) and 651-665 (TLLEESQNQQEKNEQ). Using two different techniques, five proteins (37, 40, 55, 97 and 108 kD) were identified in H9 lysates as possible candidates for gp41 binding.


Subcellular localization of recombinant truncated Gag precursor proteins of HIV expressed in Saccharomyces cerevisiae. To determine signals contained in the HIV-1 Gag precursor implicated in protein transport. To study the localization of truncated Gag proteins expressed in Saccharomyces cerevisiae. Thin-section immunoelectron microscopy studies were performed on S. cerevisiae cells producing myristoylated or non-myristoylated Pr55gag, the core protein (p24) and several truncated Gag proteins. Pr55gag and the carboxy-terminal truncated Gag proteins were myristoylated and localized at the plasma membrane. p24 was localized in the nucleus or perinuclear membrane. However, addition of a myristoyl group to p24 targeted this molecule to the plasma membrane. The myristoylated amino-terminal 214 amino acids are sufficient to target Pr55gag to the plasma membrane. Subcellular signals implicated in protein transport are present in the core p24 polypeptide which may become dominant or accessible in the absence of the amino-myristoyl group.


Design of polymerase chain reaction primers for the selective amplification of HIV-1 RNA in the presence of HIV-1 DNA. To develop a sensitive method for the specific detection of HIV-1 RNA. Following reverse transcription, the presence of HIV-1 RNA can be detected by polymerase chain reaction (PCR) amplification. Since specific detection of HIV-1 RNA may be complicated by contamination with minute quantities of HIV-1 DNA, samples are treated with deoxyribonuclease (DNase) prior to analysis. This additional step increases the possibility of RNA degradation and sample contamination. A primer, HG141, was designed to hybridize to the poly(A) tract present in HIV-1 genomic and all HIV-1 messenger (m) RNA with its 5' end and to the region upstream of the poly(A) tract with its 3' end. The increased stability of the HG141 primer/HIV-1 RNA or complementary (c) DNA complex, enabled PCR amplification to be performed with HG141 and the return primer HG62 at an annealing temperature above the melting temperature (Tm) of the primer-HIV-1 DNA complex. After reverse transcription of samples obtained from HIV-1-infected H9 cells, HG62/141-primed PCR amplification specifically detected HIV-1 RNA sequences without the need for DNAase pre-treatment. This technique was more sensitive for the detection of HIV-1 RNA than SK38/39-primed PCR amplification of DNase-treated samples. Since the presence of HIV-1 RNA is indicative of HIV-1 replication for the presence of HIV-1 virions, the RNA-specific primer described should facilitate the assessment of HIV-1 replication and the plasma HIV-1 viral load in HIV-1-infected individuals. This should prove useful in the evaluation of the effects of therapeutic interventions on HIV-1 infection.


Gastrointestinal tissue cultures for HIV in HIV-infected/AIDS patients. The University of Calgary Gastrointestinal/HIV Study Group. To determine the prevalence of HIV in endoscopic biopsies from the esophagus, stomach, duodenum, and rectum of homosexual and bisexual men at various stages of HIV infection as part of a comprehensive study of gastrointestinal dysfunction in HIV infection. After repeated washings and mechanical disruption, biopsies obtained from 58 volunteers were individually cocultured with pooled peripheral blood lymphocytes from healthy HIV-seronegative blood donors. HIV was isolated from at least one site in 40 out of 49 patients. Esophageal biopsies were most frequently found positive (46%), followed by duodenal biopsies (44%), rectal biopsies (43%), and gastric biopsies (27%). Recovery of HIV was not related to any gastrointestinal signs or symptoms. HIV was recovered in the biopsies both from asymptomatic patients with CD4 lymphocyte counts greater than 500 x 10(6)/l and also from patients with more advanced disease receiving zidovudine therapy. The entire gastrointestinal tract appears to be a target site throughout the course of HIV infection in homosexual and bisexual men.


Osteomyelitis caused by Mycobacterium haemophilum: successful therapy in two patients with AIDS. Difficulties involved in diagnosis and response to antimicrobial therapy are described in detail for two cases of biopsy-proven osteomyelitis caused by Mycobacterium haemophilum in AIDS patients. Two large, private teaching hospitals in New York City, New York, USA. A 31-year-old woman with previous diagnoses of candida esophagitis and peripheral neuropathy (patient 1), and a 37-year-old man with Kaposi's sarcoma (patient 2). One patient was treated with a combination of rifampin, ethambutol, clofazimine, and ciprofloxacin, while the other received rifampin, ciprofloxacin and doxycycline. Both patients also received a short course of intravenous amikacin. Disease activity was monitored clinically by observing resolution of skin ulcers, lymphadenopathy, and pain and swelling in areas affected by osteomyelitis. Both patients experienced complete resolution of signs and symptoms of M. haemophilum infection. Patient 1 was treated for 17 months and remains well after 10 months without therapy. Patient 2 shows no evidence of infection after 14 months of therapy. M. haemophilum infection must be considered in the differential diagnosis of osteomyelitis in AIDS patients, although specialized culture techniques are required to isolate and identify this pathogen. Excellent clinical response can be achieved with oral antimicrobial therapy.


Low-dose oral natural human interferon-alpha in 29 patients with HIV-1 infection: a double-blind, randomized, placebo-controlled trial. To evaluate clinical efficacy and toxicity of low-dose oral natural human interferon-alpha (nHuIFN alpha) on CD4+ lymphocyte counts and clinical symptoms in patients with HIV-1 infection. Double-blind, randomized, placebo-controlled trial with crossover. Private practice specializing in the treatment of patients with AIDS. Only patients with HIV-1 infection and CD4+ lymphocyte counts between 200 and 500 x 10(6)/l were included for study. Thirty out of thirty-one patients at study entry completed treatment with placebo, and 29 completed nHuIFN alpha treatment. Mean patient age was 36 years (range, 25-58 years). The 30 patients included 26 men, of whom 22 were homosexual, and four women; five were drug users and none were currently on zidovudine therapy, although three had been previously. Patients were randomly assigned to cohorts of 10 to receive either 200 IU nHuIFN alpha once daily orally absorbed or placebo with crossover after 6 weeks. Every 2 weeks, a detailed history, physical examination, and laboratory tests, including CD4+ and CD8+ lymphocyte counts, were conducted. There was only a slight, transient increase in mean CD4+ lymphocyte counts after 4 weeks of treatment with nHuIFN alpha, compared with a slight decline when placebo was administered. This effect reached statistical significance in a subgroup of patients only and was not sustained after 6 weeks. There were no significant changes in weight and clinical symptoms. All patients remained HIV-1-antibody-positive. Treatment-related adverse reactions were not observed. Our double-blind, randomized, placebo-controlled clinical trial did not confirm a previous report of efficiency of oral nHuIFN alpha. Although non-toxic, our data do not justify the widespread use of low-dose oral nHuIFN alpha in HIV-infected patients outside controlled clinical trials.


Hepatitis B antibodies in HIV-infected homosexual men are associated with more rapid progression to AIDS. To study the influence of previous or present hepatitis B virus (HBV) infection on HIV disease progression. A prospective study of HIV-positive individuals from HIV diagnosis to diagnosis of AIDS or to the end of the follow-up period on 1 January 1991. Mean follow-up time was 62 months. The study population was recruited from a primary health-care clinic for homosexual men and followed by linkage to the National AIDS Registry. Of 876 individuals who were tested for HIV, 80 were HIV-positive and included for study. Two individuals were lost to follow-up. Differences in progression rates to AIDS according to HBV status at study entry. The adjusted relative risk of progression to AIDS for the 48 subjects who were HBV-antibody-positive at study entry was 3.6 [95% confidence interval (CI), 1.3-10.1]. A high frequency of receptive anal intercourse was also associated with more rapid HIV disease progression; adjusted relative risk 2.6 (95% CI, 1.1-5.9). Our results suggest that presence of HBV antibodies is associated with more rapid HIV-disease progression.


Seven years of recurrent severe strongyloidiasis in an HTLV-I-infected man who developed adult T-cell leukaemia. Human T-cell leukaemia/lymphoma virus type I (HTLV-I) is endemic in Japan, the Caribbean basin and Africa, where it has been aetiologically linked to certain chronic myelopathies and adult T-cell leukamia (ATL). We sought to investigate whether strongyloidiasis, a parasitic disease common in these areas, might be a cofactor in the pathogenesis of ATL, as some reports have suggested. One 35-year-old HTLV-I-seropositive French West Indian man with a 7-year history of recurrent strongyloidiasis associated with episodic hyperinfestation presenting at the Centre Hospitalier Intercommunal, Villeneuve St Georges, France. Treatment with various chemotherapeutic agents and symptomatic therapy for hypercalcaemia and antiviral therapy (zidovudine and interferon). The patient developed ATL and died shortly after, despite chemotherapy. Immunological and virological studies performed during the last 15 months of his life showed an increase of the percentage of peripheral ATL cells, and progression from a polyclonal to a monoclonal integration of HTLV-I proviral DNA in the peripheral blood mononuclear and lymph-node cells. Recurrent strongyloidiasis appears to have been a possible cofactor associated with progression from healthy carrier state to ATL in our patient.


Changing patterns in reported sexual practices in the population: multiple partners and condom use. To determine whether the pattern of change with regard to condom use and multiple sexual partners is influenced by gender or educational level. Findings from data collected from 1987 to 1990 about changes in condom use and multiple-partner activities are presented, based on telephone interviews with 9416 participants aged 18 to 44 years resident in central Scotland, UK. Change in patterns over time were modelled in a multivariate logistic regression using a linear interactive modelling program. Several models showing changes in the proportion of multiple-partner respondents and condom users yielded a complicated pattern of behavioural change in educational status and gender. There is a large difference in reported condom use and multiple sexual partners by gender, but the difference is decreasing over time. Better educated respondents increased their use of condoms while less educated respondents showed a decrease in the proportion of multiple partners.


Tuberculosis in HIV-infected subjects in Italy: a multicentre study. The Gruppo Italiano di Studio Tubercolosi e AIDS. To evaluate the strength of the association between tuberculosis and HIV infection in Italy, to assess the pattern of this association in relation to HIV transmission categories, and to describe clinical presentation of tuberculosis in a large group of Italian HIV-infected subjects. Multicentre review of clinical records. Twenty-one infectious disease hospital units in nine of the 20 administrative regions of Italy. All HIV-infected adults observed by each participating unit (in- and outpatients) between 1985 and 1989. Culture-proven tuberculosis. A total of 306 cases of tuberculosis were observed. Of these, 85 were pulmonary, 167 extrapulmonary, and 54 both pulmonary and extrapulmonary. The proportion of HIV-infected subjects diagnosed with tuberculosis increased during the study period from three out of 1380 (0.2%) in 1985 to 152 out of 6504 subjects (2.3%) in 1989 (P less than 0.0001). Two hundred and twenty-six of the 2760 (8.19%) patients with AIDS had tuberculosis within 12 months of AIDS diagnosis; the proportion of AIDS patients with tuberculosis remained stable after 1985. Compared with AIDS patients who were intravenous drug users, only homosexual AIDS patients had a significantly lower proportion of tuberculosis (178 out of 1958 versus 30 out of 522; P less than 0.02). Our data show that tuberculosis is quite common among HIV-infected subjects in Italy, and suggest that the risk of tuberculosis in these subjects has not changed. There are some differences between the pattern of the association between tuberculosis and HIV infection in Italy, compared with other industrialized countries.


The epidemiology of AIDS-associated Kaposi's sarcoma in Italy. To describe the epidemiology of AIDS-associated Kaposi's sarcoma (KS) in Italy between January 1982 and September 1991. To make this study comparable with previous research from other countries, statistical analysis of data from the Italian AIDS surveillance system was performed. Odds ratios (OR) and 95% confidence intervals (CI) were used to examine the association between several characteristics of AIDS cases and the presence of KS as the presenting clinical manifestation of AIDS. Trends in the frequency of AIDS-associated KS were also estimated. Of the 10,584 Italian AIDS cases reported up to September 1991, 720 (6.8%) had KS as the presenting clinical manifestation. In comparison with intravenous drug users (IVDU), of whom 2.6% had KS, homosexual or bisexual men had a nearly 10-fold higher risk of KS (OR, 10.2; 95% CI, 8.2-12.8), homosexual men who were also IVDU a nearly fourfold increased risk (OR, 4.4; 95% CI, 3.0-6.6) and heterosexuals a 2.6-fold risk (95% CI, 1.7-3.7). Men were more likely to have KS than women. The percentage of new AIDS cases with KS recorded each year in Italy declined from 12.0% in 1982-1986 to 5.8% in 1990-1991, a significant relative decrease of 19.0% per year (95% CI, 14.1-23.6%). The decline was observed among both IVDU (20% per year) and homosexual or bisexual men (11.4% per year). The frequency of KS was similar across age groups within each transmission category, whereas geographical differences emerged in the prevalence of AIDS-associated KS, especially among IVDU. Our data on the epidemiology of AIDS-associated KS in Italy are similar to reports from North America and Europe, which show that KS is more common among individuals who acquired HIV infection by sexual transmission rather than parenterally, and that the incidence of this neoplasm is declining over time. The still poorly understood aetiology of AIDS-associated KS needs to be investigated further.


Situational factors and thought processes associated with unprotected intercourse in young gay men. To investigate (1) the types of justifications, if any, that young gay men give themselves at the time they make the decision to have unprotected anal intercourse and (2) the types of occasion on which they are most at risk of having unprotected intercourse. In structured interviews, gay men aged 15-21 years were asked to recall two sexual encounters from the preceding 6 months: one in which they had had unprotected anal intercourse ('unsafe' encounter) and one in which they had resisted a strong temptation to have unprotected intercourse ('safe' encounter). We studied both types of encounter to enable identification of situational variables distinguishing between them. The first two factors that emerged from a Factor Analysis of the self-justification data ('unsafe' encounter, n = 219) involved, respectively, high-risk behaviour in response to a negative mood state and inferring from perceptible characteristics that the partner was unlikely to be infected. The most commonly reported self-justification was of this latter type. In respondents recalling both encounters (n = 115), sexual desires, mood, communication, and use of 'dirty talk' distinguished between the encounters. In contrast, type of partner, consumption of alcohol or drugs, desire for excitement, and use of pornography did not. Results are discussed in relation to those obtained in our earlier study of older gay men. Young gay men appear to be more single-minded about what they want to do sexually, and more likely to infer from perceptible characteristics that their partner is unlikely to be infected. In young gay men, a negative mood state is associated with unsafe sex, an opposite finding to that obtained with older gay men. The results also suggest the possible importance of failure to communicate about desires concerning safe sex and the use of 'dirty talk'; these may help to facilitate the occurrence of unsafe sex.


Two methods for assessing the risk-factor composition of the HIV-1 epidemic in heterosexual women: southeast England, 1988-1991. The prevalence of HIV-1 in the heterosexual population in southeast England between 1988 and 1991 was examined using two methods. First, district neonatal seroprevalence was compared on a geographical basis to social and demographic variables reflecting risk-factor prevalence. Second, over the same period eight children who developed AIDS within the first 12 months of life were born. The differences in seroprevalence between districts could be explained by the proportion of livebirths to women born in parts of Africa. An estimated 92% of neonatal seropositives could be associated with this demographic variable. The proportions of livebirths to women born in other countries, the prevalence of notified injecting drug use, and area measures of social deprivation, were only poorly related to HIV seroprevalence, and had no additional explanatory value. Seven of the eight (87.5%) children who developed AIDS in the first year were born to black women from Africa. Both methods suggest that a high proportion of heterosexually transmitted HIV in southeast England has been imported.


Detection of HIV proviral DNA in cortex and white matter of AIDS brains by non-isotopic polymerase chain reaction: correlation with diffuse poliodystrophy. (1) To determine whether detection of HIV proviral DNA sequences in the cerebral cortex correlates with the presence of pathological changes in this region, believed to contribute to the HIV-associated cognitive/motor complex. (2) To compare the frequency with which HIV infects cortical and subcortical regions of the brain. In vitro studies on HIV neurotoxicity suggest that HIV may be involved in the pathogenesis of cortical damage, recently defined as diffuse poliodystrophy (DPD) in AIDS. Previous detection of HIV antigen has localized HIV more frequently to subcortical than to cortical regions. It is not known whether HIV preferentially infects subcortical tissues or if viral expression varies in these two regions. HIV antigen and proviral DNA sequences were detected in anterior frontal lobe tissues using immunohistochemistry (IHC) and the polymerase chain reaction (PCR), respectively. DPD was assessed by staining with antibodies against astrocytes (GFAP) and microglia/macrophages (HAM 56). HIV proviral DNA was detected in nine out of 15 cortical samples and in 10 out of 15 white matter samples, whilst HIV p24 antigen was localized to the cortex in three out of 15 and to the white matter in seven out of 15 cases. DPD was found in 10 cases, although in five a different aetiology may have been involved. However, DPD was present in eight out of the nine cases in which HIV proviral DNA was detected in the cortex. Using a non-isotopic PCR method, HIV was detected in the brains of more cases than would be expected on the basis of IHC detection, and was present in the cortex as frequently as in the white matter. HIV, together with other factors, may contribute to the pathogenesis of DPD.


Autoantibodies typical of non-organ-specific autoimmune diseases in HIV-seropositive patients. To analyse serological aspects of systemic autoimmunity in HIV-1-seropositive patients and in individuals at risk for AIDS. The reactivity of antibodies in the serum of 100 HIV-1-seropositive patients was investigated by enzyme-linked immunosorbent assay (ELISA) using a series of antigens known to be recognized by antibodies from patients with multisystemic autoimmune diseases, such as systemic lupus erythematosus, mixed-connective tissue disease and Sjögren's syndrome. High levels of immunoglobulin G (IgG) antibodies reacting with double-stranded DNA (dsDNA), synthetic peptides of ubiquitinated histone H2A, Sm-D antigen, U1-A RNP antigen and 60 kD SSA/Ro antigen were found in 44-95% of HIV-infected patients. Among histone antibodies, the most frequent reactions were towards the carboxy-terminal region of histone H1 and to histone H2B and its amino-terminal domain 1-25. Eight HIV-1-seropositive patients at different stages of disease according to the Centers for Disease Control classification were also studied. In most cases, no obvious fluctuations were observed over several years. Antibodies were found early, and their specificity and apparent level of activity remained relatively constant. There was no evidence of such an autoimmune response in the serum of high-risk homosexual seronegative men. Although the aetiology of AIDS is known, in general the aetiology of multisystemic autoimmune diseases remains to be determined, and the sequence of events taking place remains obscure in both cases. It is possible that the large spectrum of antibodies found in HIV-infected patients reflects a specific stimulation of B-cells by nuclear antigens released by apoptosis during an early stage of disease.


Severe in vitro inhibition of erythropoiesis and transient stimulation of granulopoiesis after bone-marrow infection with eight different HIV-2 isolates. To correlate severe anaemia and frequent neutropenia in HIV-2-infected patients with an inhibitory effect on bone-marrow progenitors common to several HIV-2 isolates. The effects of eight HIV-2 isolates on early (BFU-E) and late (CFU-E) erythroid progenitors and on granulomonocytic (CFU-GM) progenitors, produced in long-term bone-marrow cultures (LTBMC), were studied. Absolute numbers of BFU-E, CFU-E and CFU-GM per culture flask were calculated weekly for each HIV-2-infected LTBMC using semi-solid clonogenic assays, and compared with those obtained in mock-infected LTBMC. Levels of significance for comparisons were determined by an analysis of variance (ANOVA). Pooled data from 24 series of LTBMC (three series for each HIV-2 isolate) revealed 80 and 100% inhibition of BFU-E and CFU-E on days 6 and 12 of LTBMC, respectively, while transient stimulation of CFU-GM was observed between days 14 and 20 of LTBMC, followed by total inhibition on day 30. These results confirm a direct inhibitory effect of HIV-2 on in vitro haematopoiesis. The similar pattern of erythroid progenitor inhibition obtained from seven out of eight isolates suggests that the inhibitory effect on erythropoiesis is a feature common to a large number of HIV-2 isolates, which correlates with clinical findings.


Identification of HIV-1 in semen following primary HIV-1 infection. To determine whether HIV could be identified in semen samples during the first few weeks after infection. A series of three homosexual men with symptomatic primary HIV-1 infection. Each subject provided a series of semen samples that was examined for HIV-1 by virus culture, polymerase chain reaction (PCR) and transmission electron micrography. The first samples obtained for each subject (17, 22 and 24 days following onset of primary HIV-1 infection) were all positive by PCR and negative by viral culture. Of 13 samples obtained during the first 80 days after onset of primary HIV-1 infection and analysed by PCR, 10 were positive. Only one of these samples was virus culture-positive. Four semen samples obtained from two subjects during treatment with zidovudine were PCR-positive. Eight samples were examined for presence of HIV-1 by electron microscopy and one was found to be positive. These results indicate that men with HIV-1 infection are potentially infectious through sexual transmission during the first few weeks after infection. The findings emphasize that individuals in all stages of HIV-1 infection should practise safer sex to reduce transmission of HIV-1.


Detection of HIV antibodies in saliva as a tool for epidemiological studies. To evaluate the use of saliva specimens for the detection of HIV antibodies among high-risk groups in epidemiological studies. Testing of saliva specimens collected by different methods from individuals with known HIV status. The most reliable method was examined for its usefulness in a field study among a high-risk group. Saliva samples were obtained either by using a cotton-wool roll ('Salivette') or as 'whole saliva'. HIV antibodies were determined using commercial enzyme-linked immunosorbent assays (ELISA). Confirmation was performed using a line immunoassay or an immunoblot assay. In 'Salivette' samples, HIV antibodies were detected by ELISA in seven out of 22 seropositive individuals. In contrast, testing of 'whole saliva' samples from 79 HIV-seropositive and 115 HIV-seronegative individuals resulted in a 100% correlation with HIV serum status. The positive reaction of 20 'whole saliva' specimens was confirmed in a line immunoassay, whereas in an immunoblot assay only seven specimens were positive, one negative, and 12 indeterminate. In an HIV prevalence study among drug users, 395 'whole saliva' samples were tested in two different ELISA. Both assays showed complete agreement in detecting 58 positive and 337 negative samples. All positive samples were confirmed by the line immunoassay. Our study demonstrates that 'whole saliva' specimens are a good alternative to blood samples in epidemiological studies of HIV prevalence in high-risk groups.


False-positive HIV antigens related to emergence of a 25-30 kD protein detected in organ recipients. The routine screening of organ donors for HIV-1 since 1985 has markedly reduced the risk of acquiring infection in organ recipients. However, commercial HIV-1 p24-antigen assays reveal false-positive reactivity in certain recipients. This observation will be discussed here. Post-transplantation sera collected sequentially from different organ recipients were tested for HIV antigen: 79 samples were from 14 kidney recipients, 57 from seven bone-marrow allografts and 18 from two heart recipients. Neutralization assays to determine specificity were performed on reactive samples. Immunoblots prepared from sera containing high levels of antigens were tested by Western blot using polyclonal anti-HIV sera. Abbott HIV-1-EIA kits detected non-neutralizable antigens in early post-transplantation sera from 12 kidney, five bone-marrow and two heart recipients. Using in-house immunoblots prepared from positive non-neutralizing antigen sera, a 25-30 kD protein was detected and shown to be the cause of the false HIV antigen cross-reactivity. False-positive HIV antigens related to the emergence of a 25-30 kD protein in early post-transplantation sera are detectable in transplant recipients.


Zidovudine prophylaxis after accidental exposure to HIV: the Italian experience. The Italian Study Group on Occupational Risk of HIV Infection. To evaluate the use of zidovudine prophylaxis in HIV-exposed health-care workers (HCW) in Italy and to determine its short-term toxicity. Longitudinal, open study with retrospective and prospective collection of data. All Italian clinical centres that care for HIV-infected patients and are licensed by the Ministry of Health to dispense zidovudine and 30 hospitals participating in the Italian Multicentre Study on Occupational Risk of HIV Infection. HCW and other individuals who accepted zidovudine prophylaxis after accidental exposure to HIV. Data were collected for 224 HIV-exposed individuals until 30 June 1991. An increase in zidovudine prophylaxis was observed. All but 10 subjects received 1000-1250 mg zidovudine per day. Anaemia (five cases), neutropenia (one case) and an increase in serum alanine aminotransferase levels (two cases) were the only haematochemical side-effects observed; none of the subjects ceased prophylaxis because of side-effects. More than 50% of subjects had constitutional reactions; as a result, prophylaxis was stopped by 29 patients. These adverse effects began within 10 days of prophylaxis; all resolved after prophylaxis was stopped. No HIV-antibody seroconversions were observed after a mean follow-up of 8 months. Zidovudine prophylaxis has become a feature of the management of occupational exposures to HIV in health-care settings; short-term toxicity is mild, dose-related and reversible. Further studies are needed to assess the risk of long-term sequelae.


High HIV seroprevalence and increased HIV-associated mortality among hospitalized patients with deep bacterial infections in Dar es Salaam, Tanzania. To correlate deep bacterial infections with HIV infection and evaluate the influence of HIV on clinical picture and outcome in patients with meningitis, pneumonia or pyomyositis. Case-control comparison of HIV seroprevalence between patients and an age- and sex-matched control group in a prospective cross-sectional study of hospitalized patients. One hundred and sixty-five patients admitted to hospital with either purulent meningitis, pneumonia or pyomyositis and 165 age- and sex-matched controls from orthopaedic/trauma wards. University Hospital, Dar es Salaam, Tanzania. Differences in HIV seroprevalence and mortality. Of 78 patients with purulent meningitis, 19 (24%) were HIV-seropositive, compared with 13 (17%) in the control group (P = 0.345). Of 36 patients with meningitis seen before a meningococcal epidemic affected Dar es Salaam, there was a statistically significant association with HIV infection (P = 0.013). Ten out of 19 (53%) HIV-seropositives died, compared with nine out of 59 (15%) seronegatives (P = 0.028). Of patients with pneumococcal meningitis, five out of six (83%) seropositives died, compared with two out of 12 (17%) seronegatives (P = 0.013). Fifteen out of 45 (33%) patients with pneumonia were HIV-seropositive, compared with four (9%) in the control group (P = 0.001). There was no difference in mortality between seropositive and seronegative patients with pneumonia. HIV seroprevalence was 62% among 42 patients with pyomyositis and 12% among 42 controls (P less than 0.0001). Eighteen out of 25 (72%) seropositive patients with pyomyositis fulfilled the World Health Organization (WHO) clinical case definition for AIDS. Response to recommended antibiotic treatment was satisfactory among patients with pneumonia and pyomyositis. These results show a strong association between pyomyositis, pneumonia and HIV infection. They also indicate an increased mortality associated with HIV infection in patients with pyogenic meningitis, especially pneumococcal meningitis. Pyomyositis should be considered an indicator of stage III HIV disease in the proposed WHO clinical staging system.


HIV risk factors in three geographic strata of rural Rakai District, Uganda. To examine risk factors for HIV-1 infection in three geographic strata (main road trading centers that service local and international traffic, small trading villages on secondary dirt roads that serve as foci for local communications, and agricultural villages off main and secondary roads) in Rakai District, Uganda. Serological, sociodemographic, knowledge/behaviors and health survey conducted in 21 randomly selected community clusters; complete data were collected for 1292 consenting adults. Fifteen per cent of the men and 24% of the women were HIV-1-positive. On univariate analysis, several sociodemographic and behavioral factors were significantly associated with risk of HIV infection, including age, place of residence, travel, occupation, marital status, number of sex partners, sex for money or gifts, history of sexually transmitted disease (STD), and history of injections. On multivariate analysis, age, residence and number of sex partners remained significantly associated with HIV infection in both sexes; a history of STD and not having been circumcised were significant in men. There was a significant interaction between place of residence and reported number of sex partners: for any given level of sexual activity, the risk of HIV infection was markedly increased if the background community prevalence was high. Sexual transmission appears to be the primary behavioral risk factor for infection, but the risks associated with this factor vary substantially between the three geographic strata. These data can be used to design targeted interventions.


HIV-1 transmission through breast-milk: appraisal of risk according to duration of feeding. To estimate the risk of HIV-1 transmission through breast-milk in children born to infected mothers, and to determine the relationship between duration of breast-feeding and risk. The study population included 168 breast-fed and 793 bottle-fed children born to seropositive mothers. All subjects were enrolled and followed-up in the Italian Register for HIV Infection in Children; HIV sero-status was defined in all children. Multivariate analysis was performed using a logistic regression model. Independent variables included biological factors (duration of breast-feeding, gestational age, clinical condition of mother at delivery, mode of delivery, birth-weight and sex). Year of birth and age when HIV infection was diagnosed were also considered in the analysis attempting to control for possible selection biases. Breast-feeding increased the risk of HIV-1 transmission. The estimated adjusted odds ratio for 1 day of breast- versus bottle-feeding was 1.19 (95% confidence interval, 1.10-1.28). The infection odds ratio of breast- versus bottle-feeding increased with the natural logarithm of the duration of practice. These results are the first to provide an appraisal of the additional risk of HIV-1 transmission associated with a seropositive mother breast-feeding her child. Biological significance of this route of transmission was supported by demonstration of a relationship between duration of breast-feeding and risk of HIV-1 transmission.


Coping with death anxiety: help-seeking and social support among gay men with various HIV diagnoses. OBJECTIVE, DESIGN AND PARTICIPANTS: We examined sources of help-seeking related to worries or concerns about death and dying and the effects of social support on death anxiety in a longitudinal sample of gay men (n = 52). Friends and primary sexual partners were the most frequent sources sought in dealing with death concerns for all groups of respondents (HIV-negative, HIV-positive asymptomatic, and HIV-positive symptomatic). Men experiencing HIV symptoms were more likely than HIV-negative and asymptomatic men to use formal sources of support (medical, psychological). Although HIV-positive symptomatic men did not differ from HIV-negative men in terms of help-seeking from family sources, they were significantly more likely to seek the help of family members than HIV-positive asymptomatic men. All three HIV groups showed significantly different mean levels of death anxiety, with HIV-negative men reporting the lowest level and HIV-positive symptomatic men the highest. Among HIV-negative men, only mental health sources of support (psychologists and clergy) were significantly related to death anxiety, measured 1 year later (beta = -0.35). These sources of support were also associated with death anxiety among HIV-positive asymptomatic men, but in the opposite direction (beta = 0.26). Contrary to expectations, men experiencing HIV symptoms benefited most from family support (beta = -0.31), although peer (beta = -0.19) and medical (beta = -0.28) support sources were also prominent. Thus, while earlier research found peers to be the most common and effective source of support among gay men, this study suggests that obtaining support from family may become particularly important as one approaches death. The effectiveness of social support in reducing death anxiety appears to vary over the course of the disease from asymptomatic to symptomatic. HIV-symptomatic men obtain support from a wide range of helpers, including medical and peer supports and family.


Which brain defects accompany cyclopia?

Which brain defects accompany cyclopia? We report a fetus with an association of cyclopia without proboscis, aprosencephaly and agnathia. Analysing literature cases and the case presented here we can suggest that: 1) not only alobar holoprosencephaly but also more severe forebrain anomalies can be a brain equivalent of cyclopia; 2) aprosencephaly can be viewed as the earliest known variant of prosencephalic series; and 3) "agnathia-holoprosencephaly" association is etiologically heterogeneous.


Laryngeal atresia sequence as part of the DiGeorge developmental field defect. The subject of the present report is a male newborn with laryngeal atresia (LA) type I, giving rise to a malformation sequence consisting of overdistended polyalveolar lungs and nonimmune fetal hydrops with massive ascites. The infant was chromosomally normal and the first child of consanguineous parents. Retention of liquid secreted by the fetal lungs in utero was the pathogenetic mechanism, responsible for the LA sequence. The LA was part of a complex constellation of anomalies, compatible with the DiGeorge developmental field defect.


MCA/MR syndrome in two female siblings: new entity or variant examples of Coffin-Lowry versus Atkin-Flaitz syndromes? We report two sisters with mental retardation, coarse facial features, telecanthus, flat malar region, prominent lower lip, kyphoscoliosis, and tapering fingers. Although these patients' phenotypes showed considerable overlap with the Coffin-Lowry and the Atkin-Flaitz syndromes, their overall picture makes these diagnoses controversial.


Hypomelanosis of Ito and severe sensorineural deafness. In this report we describe an 8-year-old boy of Algerian origin with profound sensorineural deafness and skin pigmentation anomalies consistent with the diagnosis of hypomelanosis of Ito. On the basis of this observation the etiologic heterogeneity of this condition is discussed.


Combined 10pter-->p11 and 18pter-->q11 trisomy in a 7-year-old child. We report a severely mentally retarded, dysmorphic girl aged 7 years with a 47,XX, +der(18), t(10;18)(p11.2;q11.2)mat. The phenotype of our patient is compared with 6 cases of trisomy 10p and 10 cases of trisomy 18q- from the literature. The short trisomic segment 10pter-10p11 appears to affect more the phenotype than the trisomic segment 18qter-q11.


Structure of 1,1-dichloro-2-(4-methoxyphenyl)-2,3-diphenylcyclopropane. C22H18Cl2O, M(r) = 369.3, monoclinic, P2(1)/a, a = 16.585(1), b = 17.328(1), c = 13.192(3) A, beta = 107.443(8) degrees, V = 3616.8 A3, Z = 8, Dx = 1.356 g cm-3, lambda(Mo K alpha) = 0.71069 A, mu = 3.2 cm-1, F(000) = 1536, T = 138 K, R = 0.039 for 5450 observed reflections. The structural features of the two independent molecules are quite similar except in the orientation of the methoxy group. The cyclopropane ring shows the expected bond-length asymmetry with C(2)-C(3) as the longest bond. The two cis-arranged phenyl rings adopt similar conformations as observed in diaryl-cyclopropanes, with one ring in the bisecting position and the other near the perpendicular position. The conformation of the third aryl ring is also near the perpendicular position. The overall conformation of the three aryl rings is different from the helical propeller conformation consistently observed in tamoxifen and all other known tri(tetra)aryl-vinyl systems.


Structure of asperketal B.

Structure of asperketal B. 3,7,11-Trimethyl-13-oxabicyclo[8.3.0]trideca-2,6-diene-12-spiro-2' -(5',5'-dimethyltetrahydrofuran), asperketal B, C20H30O2, M(r) = 302.46, orthorhombic, P2(1)2(1)2(1), a = 10.064(1), b = 22.214(2), c = 8.330 (1) A, V = 1862.3 A3, Z = 4, Dx = 1.08 g cm-3, Cu K alpha, lambda = 1.54178 A, mu = 4.55 cm-1, F(000) = 664, T = 294 (1) K, R = 0.031, wR = 0.027 for 953 data. The backbone of the molecule is composed of a cyclodecadiene ring which is cis fused to a bicyclic ketal system. The relative configurations at C(1), C(10), C(11) and C(12) are 1S*, 10R*, 11R* and 12R*.


Structure of tris(dicyclohexylphenylphosphine)gold(I) perchlorate. [Au(P(C6H11)2(C6H5))3][ClO4], M(r) = 1119.59, trigonal, R3c, a = 13.192(5), c = 52.83 (2) A, V = 7962 (9) A3, Z = 6, Dx = 1.401 g cm-3, lambda(Mo K alpha) = 0.71073 A, mu = 29.5 cm-1, F(000) = 3468, T = 296 K, final R = 0.047 for 1321 unique observed reflections. The Au atom in the anion and the perchlorate ion in [Au(Cy2PhP)3][ClO4] lie on a threefold axis. The complex has an almost ideal trigonal-planar geometry, with an Au--P distance of 2.421 (3) A, P--Au--P angles of 119.9 (3) degrees, and the Au atom only 0.08 (2) A out of the plane defined by the three P atoms.


Structure of aqua[N,N'-ethylenebis(N-carbamoylmethylglycinato)]copper(II) dihydrate. The structure consists of a copper(II) cation octahedrally coordinated to the polyaminocarboxylate ligand through five ligating atoms: one N atom of the ethylenediamine ring, two carboxylate O atoms and a molecule of water form a square plane, while one amide O and the other ethylenediamine-ring N atom are above and below the plane. The latter two atoms display tetragonal distortion. Eight intermolecular hydrogen bonds involve H, N and O atoms of the complex as well as the two water molecules of crystallization.


Structure of calcium 2,6-difluorobenzoate dihydrate. Ca2+.2C7H3O2F2-.2H2O, M(r) = 390.3, monoclinic, C2/c, a = 17.584 (4), b = 10.771 (3), c = 7.887 (2) A, beta = 91.28 (2) degrees, V = 1493 A3, Z = 4, Dm = 1.75, Dx = 1.74 g cm-3, lambda(Mo K alpha) = 0.71073 A, mu = 4.92 cm-1, F(000) = 792, T = 293 K, final R = 0.037 for 2415 unique observed reflections. The eight-coordinate Ca2+ ion is linked to six carboxylate O atoms from four different 2,6-difluorobenzoate ions and two water molecules. Each 2,6-difluorobenzoate ion chelates one Ca2+ ion and forms unidentate bridging linkages to two other Ca2+ ions leading to a polymeric structure. Unlike the situation in calcium 2-fluorobenzoate, the two F atoms in this structure are not involved in significant C-F...H-O hydrogen bonding.


Structure of lansimide 2, a product from Clausena lansium. The natural product lansimide 2 is a 1:1 mixture of two different cyclic amides, C18H17NO2.C18H19NO3. The mixture crystallizes as a molecular pair in the centrosymmetric space group P21/n. M(r) = 576.69, monoclinic, a = 20.151 (2), b = 6.2984 (4), c = 24.051 (2) A, beta = 104.339 (8) degrees, V = 2957.4 A3, Z = 4, Dx = 1.30 g cm-3, Cu K alpha, lambda = 1.54178 A, mu = 6.1 cm-1, F(000) = 1224, T = 163 (1) K, R = 0.033, wR = 0.034 for 5002 observed reflections.


Structure of bis(4-chlorophenolato)[hydrotris(3,5-dimethyl-1- pyrazolyl)borato]oxomolybdenum(V). [Mo(C15H22BN6)(C6H4ClO)2O], M(r) = 664.24, triclinic, P1, a = 10.585 (2), b = 12.068 (3), c = 13.728 (3) A, alpha = 88.01, beta = 69.94, gamma = 65.78 degrees, V = 1490.8 A3, Z = 2, Dx = 1.48 g cm-3, Mo K alpha, lambda = 0.71073 A, mu = 6.5 cm-1, F(000) = 678, T = 296 (1) K, R = 0.034, wR = 0.049 for 4634 observed independent reflections with F2 greater than 3 sigma (F2). This is the second structurally characterized mononuclear monooxo transition-metal complex containing the phenolato ligand. The molecule exhibits a distorted octahedral coordination geometry, and the Mo atom is ligated by a terminal O atom, two p-chloro-substituted phenolato groups, and a tridentate facially coordinated hydrotris(3,5-dimethylpyrazolyl)borate ligand (L).


Structure of a protected C3-C10 subunit of erythromycin and its C8 epimer. (1) (2S,3R,4R,6R)-3,4-O-Carbonyl-7,7-dimethylenedithio-2,4,6-trimet hylnonane-1,3,4-triol, C15H26O4S2, M(r) = 334.49, triclinic, P1, a = 6.460 (2), b = 8.917 (3), c = 15.616 (5) A, alpha = 83.60 (3), beta = 83.41 (2), gamma = 89.52 (2) degrees, V = 888.0 (5) A3, Z = 2, Dx = 1.25 g cm-3, mu = 2.980 cm-1, lambda (Mo K alpha) = 0.7107 A, F(000) = 360, T = 298 K, R = 0.0465 for 1832 reflections [Fo greater than or equal to 4 sigma (Fo)]. (2) (2S,3R,4R,6S)-3,4-O-Carbonyl-7,7-dimethylenedithio-2,4,6-trimet hylnonane-1,3,4-triol, C15H26O4S2, M(r) = 334.49, monoclinic, P21, a = 8.1849 (8), b = 8.9456 (14), c = 12.0258 (14) A, beta = 100.878 (8) degrees, V = 864.7 (2) A3, Z = 2, Dx = 1.28 g cm-3, mu = 3.060 cm-1, lambda (Mo K alpha) = 0.7107 A, F(000) = 360, T = 298 K, R = 0.0569 for 2001 reflections [Fo greater than or equal to 4 sigma (Fo)]. The two diastereomers differ in configuration at C6. For (1) there are two unique molecules in the unit cell. These two molecules differ in conformation by a rotation about the bond C7-C8. The molecules are hydrogen bonded into infinite chains along b. The hydroxyl O atom of molecule (2), O10', acts as both a donor and an acceptor in hydrogen-bonding interactions with the carbonyl O atom, O14, and the hydroxyl H atom, H10, of molecule (1).(ABSTRACT TRUNCATED AT 250 WORDS)


Solid-state conformations of aminosuccinyl peptides: structure of tert-butyloxycarbonyl-L-prolyl-L-aminosuccinyl-glycyl-L-alanine methyl ester (Boc-L-Pro-L-Asu-Gly-L-Ala-OMe). A case of pseudo-translational symmetry. C20H30N4O8, M(r) = 454.48, monoclinic, P2(1), a = 13.411 (2), b = 12.592 (2), c = 14.710 (1) A, beta = 104.30 (1) degrees, V = 2407 (6) A3, Z = 4, Dx = 1.254 Mg m-3, lambda (Cu K alpha) = 1.5418 A, mu = 0.783 mm-1, F(000) = 968, room temperature, final R = 0.086, wR = 0.080 for 4055 observed reflections. The title compound is a model for the intermediate formed in the deamidation reaction of porcine adrenocorticotropin hormone. The structure presents a pseudo-translational symmetry and was solved by using a modified version of the SIR88 package. In the refinement, few stereochemical restraints were needed to handle the static disorder shown by the C-terminal fragment of one molecule in the asymmetric unit. The conformation of the two independent molecules is almost identical and is a II' beta-bend, stabilized by an intramolecular hydrogen bond. In the crystal, screw-related molecules are linked by hydrogen bonds. The two molecules in the independent unit are related by the translation vector u = 0.4962 (2)a + 0.7310 (2)b + 0.5075 (2)c.


1,2-Naphthalenedicarboxylic acid: structures of channel clathrates and an unsolvated crystalline phase. (1) 1,2-Naphthalenedicarboxylic acid-diethyl ether, C12H8O4.nC4H10O, M(r) = 216.19, tetragonal, I4(1)/a, a = 22.086 (3), c = 9.463 (3) A, V = 4616 (2) A3, Z = 16, F(000) = 1792 (without ether), F(000) = 1873 (with 2.7 molecules of ether per unit cell), Dx = 1.24 g cm-3 (without ether), Dx = 1.31 g cm-3 (with 2.7 molecules of ether per unit cell), lambda(Mo K alpha) = 0.71073 A, T = 296 K, mu = 0.88 cm-1, R = 0.052 for 1130 unique reflections having I greater than 3 sigma I. (2) 1,2-Naphthalenedicarboxylic acid, C12H8O4, M(r) = 216.19, triclinic, P1, a = 9.027 (1), b = 9.234 (1), c = 7.256 (1) A, alpha = 106.08 (1), beta = 90.79 (1), gamma = 111.80 (1) degrees, V = 535.0 (1) A3, Z = 2, F(000) = 224, Dx = 1.34 g cm-3, lambda (Mo K alpha) = 0.71073 A, T = 296 K, mu = 0.95 cm-1, R = 0.043 for 1216 unique reflections having I greater than 3 sigma I. (3) 1,2-Naphthalenedicarboxylic acid-dimethoxyethane, C12H8O4.nC4H10O2, M(r) = 216.19, tetragonal, I4(1)/a, a = 22.067 (2), c = 9.465 (2) A, V = 4609 (1) A3, Z = 16, Dx = 1.25 g cm-3 (without dimethoxyethane), Dx = 1.39 g cm-3 (with 4.4 molecules of dimethoxyethane per unit cell), lambda(Mo K alpha) = 0.71073 A, T = 296 K.(ABSTRACT TRUNCATED AT 250 WORDS)


Clinical evaluation of Clearfil photoposterior: 3-year results. The purpose of this study was to evaluate a new resin composite/bonding restorative system in clinical trials involving human subjects. Sixty restorations were inserted in Class I and Class II preparations in premolars and molars. The enamel margins of the preparations were etched for 60 seconds with 37% phosphoric acid gel. The dentinal surfaces of cavity preparations were etched for 40 seconds with 37% phosphoric acid in glycerine (K-etchant gel) and bonding agent (Clearfil Photo Bond) applied. A resin composite (Clearfil Photoposterior) was placed in three increments with a 20 second light cure of each increment and a 60 second light cure of the final increment. All the restorations were evaluated using the USPHS system and M-L indirect scale. At 36 month recalls, compared to baseline, surface texture for essentially all the restorations was rated Bravo, while all other characteristics were rated Alpha. Secondary caries was reported for one restoration during the third year of clinical use. Wear showed an adjusted mean value of 14.6 microns at 36 months or 4.9 microns per year. No cases of clinical post-operative sensitivity to hot, cold, percussion and foods were reported during the length of the study. Clearfil Photoposterior resin composite system has exhibited remarkable wear resistance and no post-operative sensitivity throughout the length of the study.


Moist versus dry dentin: its effect on shear bond strength. This study compared the shear bond strengths of dentin bonding systems applied to air dried and blot (moist) dried dentin. Five systems with primers possessing hydrophilic properties were evaluated. Three contained acetone. All Bond, Amalgambond, Mirage Bond and Tenure all produced significant statistical improvement in shear bond strength values when applied to moistened dentin. Mirage Bond values quadrupled. Bond strength values with Gluma were compromised by the presence of moisture. It was concluded that acetone probably facilitated deeper and more complete penetration of resin into dentin to enhance micro-mechanical retention. Amalgambond, while free of acetone is strongly hydrophilic and is known to form substantial mechanical bonding through the formation of a resin rich superficial layer of dentin (hybridization). Gluma while hydrophilic does not appear to possess the same behavioral characteristics embodied in the other systems as evidenced from lack of a bond to moist dentin.


Microleakage of Vitrebond/P-50 Class II restorations. Thirty extracted human mandibular permanent first and second molars were used in this study. Class II preparations were made extending 1 mm below the CEJ at the mesial and 1 mm above the CEJ at the distal aspects. In 15 of the teeth Vitrebond was applied to all exposed dentin (A) while in 15 teeth the gingival floor was left exposed (B). After cure, the enamel margins were etched with H3PO4 gel and the Vitrebond surfaces were treated with Scotchbond 2. The P-50 was transferred to the approximal boxes and occlusal aspects in three increments, each compressed firmly and cured for 60 seconds. The restored teeth were stored in saline at 37 degrees C for 1 week. The teeth were thermocycled x250 in 0.5% basic fuchsin between 8 degrees C and 50 degrees C with a dwell time of 15 seconds. The teeth were embedded in epoxy resin and five mesiodistal sections cut. Microleakage at the mesial and distal aspects were scored from 0 to 3 depending on the extent of the microleakage. The data were analyzed by the Wilcoxon 2-sample and the matched pair signed rank tests. Leakage above the CEJ was significantly less than below the CEJ and significantly reduced when Vitrebond was extended to the cavosurface margins.


Shear bond strength of repaired glass ionomers. This in vitro study investigated repairs to glass ionomer cements (GIC) with a new GIC layer added after different time intervals (15 minutes, 24 hours, 6 days) and after different types of surface treatments. The results indicated: 1) GIC can be repaired with a new GIC layer added on with specific types of surface treatment. The shear bond strength created at the interface attained no less than 65% of the value for unrepaired specimens; 2) The surface treatment that best enhances the bond was either 20 seconds of etching with phosphoric acid or roughening the surface followed by acid etching. The latter showed higher values but not at a statistically significant level; 3) Both Ketac-Fil and Fuji II provided high bond strengths when the repair occurred on a newly set surface (15 minutes); 4) When Ketac-Fil and Fuji II specimens were repaired at 24 hours, shear bond strength was lower compared to the repair bond strength at 15 minutes and demonstrated less cohesive ability; 5) When 6-day-old specimens were repaired, Fuji II provided higher bond strength values than Ketac-Fil.


Evaluation of resins for provisional restorations. An in vivo study of two resin materials (Barricaid and Caulk Temporary Crown and Bridge Resin) was done to determine the retention, post-operative sensitivity, and fabrication time of provisional restorations made from these materials. Following the placement of these resins in 67 intracoronal cavity preparations of 19 adult patients, a baseline evaluation was made which included a clinical examination and color slides. Twenty-four hours after the temporary restorations were placed, the patients completed evaluations of the post-operative sensitivity experienced. There was no difference in post-operative sensitivity between the teeth restored with Barricaid or Caulk Temporary Crown and Bridge Resin. At the insertion appointment of the final restoration, the interim restoration's success rate was determined. There was no difference between the retention of the two provisional materials. Fabrication time was significantly different with Barricaid restorations requiring less than one-half the fabrication time of the Caulk Temporary Crown and Bridge Resin material.


Relative fit of new denture resins polymerized by heat, light and microwave energy. This study compared in vitro the relative fit of seven denture resins polymerized by different methods to their gypsum casts. Relative fit in the molar-to-molar region of the resin bases on their stone casts was evaluated independently by five evaluators at three times (after processing, after polishing and after storage in water) and ranked using non-parametric statistics. The denture resins polymerized by microwave energy, (Acron MC), low heat, (Perform, 45 degrees C), and visible light, (Triad) fit better after polishing and after storage in water than those resins polymerized at higher temperatures (Lucitone 199, 74 degrees C and Accelar 20, Compak and Permacryl 20, 100 degrees C). The traditional heat-polymerized resin (Lucitone) had an average fit after storage in water.


Comparison of a chlorhexidine rinse and a wooden interdental cleaner in reducing interdental gingivitis. The purpose of this study was to evaluate the effectiveness of an antimicrobial rinse (chlorhexidine) compared to a positive control of mechanical oral hygiene in reducing interdental gingival inflammation. The mechanical group showed a significantly greater reduction in interdental gingivitis as determined by bleeding compared to the chemical rinse. Even though the chemical rinse has been shown to be effective in reducing inflammation on the visible buccal and lingual gingival surfaces, it is significantly less effective than the mechanical device in reducing bleeding in the interdental area.


Effect of temporary cements on the bond strength of a resin cement. This study evaluated the effect of temporary cements with or without eugenol on the bond strength of a dual-cure resin cement to dentin. Etched, silanated Dicor buttons were bonded to dentin surfaces after pretreatment with the cements. The buttons were sheared in an Instron testing machine. The results showed that shear bond strength is not affected by the temporary cements, if the dentin is cleaned with pumice and treated with Prisma Universal Bond 3 dentin bonding system.


Sealing ability of two intermediate restorative materials in bleached teeth. This study compared the radicular penetration of bleaching agents in endodontically treated teeth containing an IRM base, a Cavit base, and no base. Forty-five extracted human maxillary central incisors treated with conventional endodontic therapy with laterally condensed gutta percha and sealer were randomly divided into three groups: (1) Cavit base, (2) IRM base and (3) no base. In groups 1 and 2, a 3.5 mm thickness of base material was placed at the time of obturation. After storage in saline for 1 week, the teeth were bleached with a mixture of 35% hydrogen peroxide and sodium perborate, combined with a 10% methylene blue dye solution, using a combination thermocatalytic and non-thermocatalytic bleaching technique. The apical distance of dye penetration was measured. The control group demonstrated dye penetration to the apex, indicating that a base is required to prevent leakage of bleaching agents when this combination of bleaching techniques is used. The mean distance of leakage was 3.43 mm (+/- 1.14) for the Cavit group and 5.94 mm (+/- 1.72) for the IRM group. Analysis with a t-test revealed that Cavit was a more effective barrier to leakage than IRM (T = 4.20, P less than 0.001).


Effect of axial load and temperature cycling on microleakage of resin restorations. This study evaluated the microleakage of Class V resin restorations subjected to temperature and axial load cyclings. The preparations were made at the mesial and distal aspects of 29 mandibular first and second molars. The enamel margins were beveled, acid etched, washed and dried. Kerr XR Bonding System was applied to the dentin and etched enamel and Herculite composite cured in two increments. The teeth were stored in saline for 7 days, thermocycled x500 in 0.5% basic fuchsin between 8 degrees C and 50 degrees C (A); subjected to an occlusal load of 34 MPa in the dye without thermocycling (B); or followed by thermocycling (C). The leakage was scored from 0 to 4 at both the enamel and cementum aspects of the restorations. The data were analyzed by the Kruskal-Wallis test. The microstrain of five restored teeth subjected to an occlusal load of 34 MPa was measured. Microleakage of the mesial restorations was significantly greater at the cementum aspects of the restorations subjected to both temperature and occlusal loading when compared to the restorations subjected to temperature cycling or load cycling only. The microstrain in eight of the 10 restorations was significantly greater at the cementum aspects of the restorations than at the enamel aspects.


Dental health care workers' response to the HIV epidemic. Random samples of Minnesota DHCWs were surveyed in late 1989 regarding HIV-related and infection control KAPs. Response rates were: dentists 69% (438/631); hygienists 73% (439/603); and assistants 56% (384/691). More than 50% of DHCWs said they did not have sufficient information to safely and effectively provide care for HIV-infected patients. Use of infection control techniques varied considerably. Parenteral injuries were relatively high, but only 5% of DHCWs believed they could have been exposed to HIV from these occurrences, and few DHCWs sought medical evaluation. Less than 45% of offices had a blood/body fluid exposure staff protocol, and few offices had a policy for HIV-infected staff. Nearly twice as many DHCWs said offices have an ethical versus a legal duty to treat HIV-infected persons. Low percentages of DHCWs believed the private practice dental office is the best place to treat HIV-infected patients, but approximately 50% said they would provide care. Twenty percent indicated that a diagnosed HIV-infected person had been seen at their office. Seventy-six percent said staff had been uncomfortable treating HIV-infected patients, 14% said staff had refused to treat, and 10% said referrals were difficult. DHCWs exhibited substantial improvements in their HIV-related KAPs compared to previous surveys. Nevertheless, additional cognitive and behavioral changes are necessary to ensure that all DHCWs provide care with the highest technical, legal, and ethical standards for all patients.


Mammalian bites: risk and management.

Mammalian bites: risk and management. Human and animal bites can result in bacterial infection of the wound, and may be associated with the transmission of viral pathogens, including blood borne pathogens. The management of bite injuries requires local wound care, antibiotics if appropriate and prophylaxis against transmission of tetanus and viral pathogens including Hepatitis B virus. A review of bite injuries and management is presented.


Inhibition of human renin by rat plasma. Rat angiotensinogen is a competitive inhibitor of the human renin-substrate interaction. Human renin can cleave rat angiotensinogen, yet infusion of human renin into rats causes only a modest increase in blood pressure. We therefore investigated whether there is a factor in rat plasma which inhibits human renin activity. The addition of 20% normal rat plasma to human plasma had a slight, but not significant, inhibitory effect on the rate of angiotensin formation, while nephrectomized rat plasma, which had a seven-fold higher concentration of angiotensinogen, caused a dose dependent inhibition (20 to 70%). The rat plasma inhibitor copurified with angiotensinogen. Analysis of the kinetics of the human renin-human substrate reaction and of the human renin-rat substrate reaction revealed that the rate of angiotensin I production in the presence of both substrates could be entirely accounted for by assuming that rat and human angiotensinogens are competitive inhibitors of each other. These results show that human renin can cleave rat substrate but the reaction rate is extremely slow relative to the cleavage of human angiotensinogen. They also indicate that rat angiotensinogen is an effective competitive inhibitor of the human renin-substrate reaction. These results may be relevant to the development of renin inhibitors and to transfection studies involving heterologous renin or substrate genes.


Metabolic cardiovascular risk factors and sodium sensitivity in hypertensive subjects. Hypertension has previously been suggested to be a part of a metabolic syndrome also involving hyperlipidemia, hyperinsulinemia, and decreased insulin sensitivity. In the present study, 10 untreated hypertensive subjects were challenged with a high-salt diet (20 g NaCl) for 1 week after 7 days on a low-salt diet (less than 3 g). The difference in mean blood pressure (MBP) at the end of the high-salt diet v the low-salt diet was denoted salt sensitivity. We related the salt sensitivity to indices of glucose and lipid metabolism and studied the effect of salt deprivation on these metabolic variables. Salt sensitivity was found to be significantly correlated to HDL cholesterol (r = 0.79, P less than .007), insulin sensitivity (M value at the euglycemic clamp, r = 0.68, P less than .003), and fasting serum insulin (r = 0.69, P less than .04). Salt deprivation induced an increase in fasting insulin (P less than .03), but did not significantly affect any other indices of glucose and lipid metabolism. In conclusion, our study shows that hyperinsulinemia, decreased sensitivity to insulin, and low levels of HDL cholesterol were most commonly seen in hypertensive subjects with a low sodium sensitivity. A putative mechanism might be an increased activity in pressor systems also affecting glucose and lipid metabolism.


Improvement in metabolic risk factors for coronary heart disease associated with cilazapril treatment. Patients with hypertension tend to be glucose intolerant, hyperinsulinemic, and dyslipedemic. Since all of these changes increase risk of coronary heart disease (CHD), it is important to know what effect antihypertensive treatment has on these variables. The current open-labelled, uncontrolled study was initiated in order to extend our understanding of these issues. This study was performed in 19 patients with hypertension who were started on an angiotensin converting enzyme (ACE)-inhibitor, cilazapril, with hydrochlorothiazide (HC) added if needed to control blood pressure. Plasma glucose and insulin responses to oral glucose and lipid concentrations were measured before, 26, and 52 weeks after starting treatment. Patients treated with either cilazapril (n = 9) or cilazapril+HC (n = 10) did not differ in terms of original (mean +/- SEM) blood pressure (159 +/- 5/101 +/- 1 v 156 +/- 4/103 +/- 2 mm Hg), age (53 +/- 2 v 54 +/- 2 years), sex distribution (5M:4F v 7M:3F), or body mass index (24.4 +/- 0.5 v 24.2 +/- 0.9 kg/m2). Blood pressure was also similar after 26 (137 +/- 4/88 +/- 1 v 133 +/- 3/90 +/- 1 mm Hg) and 52 (137 +/- 4/87 +/- 1 v 134 +/- 4/89 +/- 2 mm Hg) weeks of treatment. Plasma glucose and insulin responses decreased by 8 +/- 3% (P less than .05) and 25 +/- 9% (P less than .002), respectively, in cilazapril-treated patients, but did not change in those treated with cilazapril plus HC.(ABSTRACT TRUNCATED AT 250 WORDS)


Dietary sodium and the antihypertensive effect of nifedipine in spontaneously hypertensive rats. To assess the interaction of dietary sodium and the antihypertensive response to a calcium antagonist, spontaneously hypertensive rats (SHR) were given a diet of regular or increased (120 v 342 mumol Na+/g food) sodium intake from 4 until 16 weeks of age. Nifedipine was added at 10 weeks of age. This level of sodium intake did not enhance the development of hypertension in SHR. In rats with the regular sodium intake, nifedipine caused only a minor decrease in blood pressure. In contrast, with increased sodium intake nifedipine caused a marked antihypertensive response, preventing the rise in blood pressure occurring between 10 and 16 weeks of age. This enhanced response was associated with a diminished blood pressure fall from ganglionic blockade. These results indicate that modest increases in sodium intake enhance the blood pressure response to a calcium antagonist possibly by potentiating its inhibitory effects on sympathetic activity.


The influence of age on renal function and renin and aldosterone responses to sodium-volume expansion and contraction in normotensive and mildly hypertensive humans. To determine the effects of age on the responses of renin, aldosterone (PA), sodium excretion, and renal function to provocative maneuvers, we performed volume expansion and contraction in 390 normotensive and 212 hypertensive subjects in the second to seventh decades of life. The subjects were classified as Na-sensitive if their mean blood pressure was 10 mm Hg or more higher after volume expansion than volume contraction. Sodium sensitivity was associated with hypertension and increasing age. Plasma renin activity decreased with age under basal, stimulated, and suppressed conditions; the decrease was greater in hypertensives than in normotensive persons. The PA values were greater in hypertensives than in normal subjects after volume expansion. There was an age-related decrease in PA values after volume contraction in normal, but not in hypertensive, persons. With volume expansion, hypertensive persons exhibited "exaggerated natriuresis." There was an age-related increase in natriuresis in both groups; the increase was greater in hypertensives than normal subjects. Creatinine clearance decreased with age; however, the rate of decrease in this cross-sectional study was not different in hypertensive and normotensive subjects. These observations may have a bearing on why NaCl affects the blood pressures of older individuals more than younger persons.


The reliability of noninvasive continuous finger blood pressure measurement in patients with both hypertension and vascular disease. In conditions of compromised peripheral circulation, the measurement of noninvasive continuous finger blood pressure with the Finapres device may show reduced accuracy. We therefore compared Finapres blood pressure (FINAP) with intrabrachial blood pressure (IAP) responses to the Valsalva maneuver and arising in 12 patients in whom the peripheral circulation was expected to be compromised due to the combination of therapy-resistant hypertension and vascular disease. During a 30 sec control period the FINAP--IAP differences were -15.7 +/- 18.8 mm Hg (mean +/- SD) for systolic, -20.1 +/- 15.7 mm Hg for mean, and -13.5 +/- 15.7 mm Hg for diastolic pressure. During the Valsalva maneuver and prolonged standing Finapres reproduced the essential characteristics of the changes in IAP in all patients. However, in individual patients, the magnitude of the intraarterial blood pressure response was sometimes over- or underestimated by Finapres. Nevertheless, the group averaged blood pressure, in particular mean and diastolic pressure, response to cardiovascular stimuli, was well reproduced by Finapres. In conclusion, as expected physiologically, individual Finapres measurements in patients with vascular disease do not always equal the intrabrachial pressure and should thus be evaluated with care. However, the Finapres device can be used with sufficient confidence to study the group averaged responses to cardiovascular stimuli in these patients.