Gardnerella vaginalis infection and sexual contact in female children. Gardnerella vaginalis (GV) infection has been reported as being acquired via sexual contact in adults and as an indicator of sexual contact in female children (DeJong, 1985). The purpose of this study was to determine if GV infection was more commonly found in 191 female children who gave a history of sexual contact and/or were infected with Neisseria gonorrhoeae (GC) or Chlamydia trachomatis (CT) (Group 1), compared with 144 female children evaluated for possible sexual abuse and found to have no such history or infection with GC or CT (Group 2), or 31 female children (friends of the authors) without such a history or GC or CT infection (Group 3). Vaginal GV was found in 5.3% of Group 1, 4.9% of Group 2 and 6.4% of Group 3 (p > .05). Also, vaginal GV infection was not related to the type of sexual contact or race, but did increase with age in white female children. Because vaginal GV infection is not more commonly found in children with a history of sexual contact than those without such a history, the finding of GV in a vaginal culture in an individual case would not be a reliable marker of sexual contact. Routine culturing for GV is not recommended as part of a sexual abuse workup.


The pattern of sugar consumption in social class groups of young adolescents in Northern Ireland. The pattern of sugar consumption in a sample of 350 11-12-year-old adolescents was examined. Their knowledge of the sugar content of a range of common foodstuffs was also investigated. There were only small differences between the social class groups in mealtime sugar consumption. The frequency of total food and drink was significantly higher in the low social class groups and this was mainly explained by significantly higher between meal consumption of solid food which contained sugar. The level of knowledge of the sugar content of foods was significantly higher in the higher social class groups. Fifty-two per cent of the questions were answered correctly, with a range of 9-91 per cent for individual foodstuffs.


Sexual abuse prevention education for young children: a comparison of teachers and parents as instructors. The purpose of this study was to compare teachers and parents as instructors of a personal safety program. One hundred seventy-two Head Start preschoolers were randomly assigned to a personal safety program taught by their teachers, parents, both teachers and parents, or to a general safety control program. Following program participation, children taught the personal safety program by their teachers, parents, or both, demonstrated greater knowledge about sexual abuse and higher levels of personal safety skills compared with those in the control group. Gains in knowledge and skills were maintained at the 5-month follow up. Children taught by their parents showed greater improvements in recognizing inappropriate-touch requests and in their personal safety skills compared with children taught by their teachers, and children who received the program both at home and school were better able to recognize appropriate-touch requests and to demonstrate higher levels of personal safety skills compared with children taught only at school. The emotional costs associated with participating in the program were minimal, and both parents and children rated the program positively. The advantages of home-based instruction for young children are discussed and suggestions for future research are offered.


Self-reported childhood and adolescent sexual abuse among adult homosexual bisexual men. From May 1989 through April 1990, 1,001 adult homosexual and bisexual men attending sexually transmitted disease clinics were interviewed regarding potentially abusive sexual contacts during childhood and adolescence. Thirty-seven percent of participants reported they had been encouraged or forced to have sexual contact before age 19 with an older or more powerful partner; 94% occurred with men. Median age of the participant at first contact was 10; median age difference between partners was 11 years. Fifty-one percent involved use of force; 33% involved anal sex. Black and Hispanic men were more likely than white men to report such sexual contact. Using developmentally-based criteria to define sexual abuse, 93% of participants reporting sexual contact with an older or more powerful partner were classified as sexually abused. Our data suggest the risk of sexual abuse may be high among some male youth and increased attention should be devoted to prevention as well as early identification and treatment.


Grooming the victim: an analysis of a perpetrator's seduction letter. The authors review the current literature on the sexual victimization of adolescent males with attention given to victim characteristics and victim selection factors and strategies. Following this review, a letter written by a middle-aged man to entice a teenage boy into sexual activity is presented and analyzed. The strategy used by the letter-writer is to refute the usual reservations a teenage boy might have about engaging in sexual activity with a man. The approach used in the letter and the ensuing analysis are generalizable to teenage boys experiencing similar encounters and highlight the sophisticated seduction and grooming strategies used to sexually victimize adolescent males.


The possibility of school milk as a vehicle for fluoride: epidemiological, organisational and legal considerations. The aim of this study was to investigate the epidemiological, organisational and legal considerations of using school milk as a vehicle for fluoride. The background to the work was the need to develop alternative methods of fluoride supplementation for high risk groups living in areas where water fluoridation is unlikely. St Helens in Merseyside was chosen as the study area, where 23 per cent of 4-year-old children were identified as having a high caries experience (dmft > or = 4). It was found that 65 per cent of 3 and 4-year-old children attend local authority educational facilities, where milk is provided on a daily basis for children aged 2 to 7 years. This group included 62 per cent of the 4-year-old group with high caries experience. The legal aspects of adding fluoride to milk were found to be complex but it was concluded that there may be considerable potential for using school milk as a vehicle for fluoride, and a large-scale study is now planned.


An exploratory study of barriers to promoting oral hygiene through carers of elderly people. This paper outlines the main findings of an exploratory study into carers' attitudes towards looking after the oral hygiene needs of their elderly patients and relatives. The data were collected using eight group discussions covering a cross-section of carers and carer settings throughout central Scotland. A range of barriers to improving levels of care was identified. The paper concluded that to make positive progress, a comprehensive oral hygiene programme is required to break down these barriers. It is believed that a strong educational policy based upon carers' needs should form the main impetus of such a programme.


Prevalence of dental caries and enamel defects in the primary dentition of Antiguan pre-school children aged 3-4 years including an assessment of their habits. In 1989 a national survey was carried out on children aged 3 to 4 years attending nursery schools, to investigate the prevalence of caries experience, nursing bottle caries and enamel defects in the primary dentition, and these children's dentally related habits. In the first part of the study, examination of 482 Antiguan children showed that the dmft and dmfs values were 0.80 and 1.26 respectively, and that 77 per cent of the children were caries free; 4.6 per cent of children had nursing bottle caries; and enamel defects occurred in 24 per cent of children. No significant difference was found in oral health between urban and rural samples. In the second part, which was an interview survey, habits such as thumb sucking (13 per cent), not brushing their teeth (3 per cent), and swallowing fluoride toothpaste (13 per cent) were found among 369 children. In the third (a questionnaire) survey, a response rate of 63 per cent was obtained. Significantly more of the children with nursing bottle caries (78.6 per cent) had the habit of sleeping with a feeding bottle than occurred in caries free children (25.6 per cent), but there was no difference in the infant feeding pattern. The children with enamel defects were breast fed for a shorter period and had an earlier introduction to bottle feeding, compared with children without enamel defects. In the final part of the survey, an assessment of snack eating habits at school, a 58 per cent response rate was achieved. The majority of children often brought healthier snacks, together with daily sugar-rich drinks. Significantly more caries free children brought sugary snacks less frequently than children with caries experience.


Child abuse in India: an empirical report on perceptions. A small but growing body of literature has begun to provide an understanding of child abuse in India. However, there is a dearth of empirical evidence to support general observations. Because it is believed that child abuse in India has not received adequate attention primarily because of a general lack of sensitivity to the issue, this study sought to assess perceptions of child abuse by Indian nationals. Comparisons between social workers, other human service professionals, and those not involved in human services fields revealed that there was negligible variation in perceptions of the severity of different forms of abuse. Cross-cultural comparisons with a U.S. study indicated some differences in perceptions. Implications of the findings are discussed.


The effect of school dental screening on dental attendance. The results of a randomised controlled trial. The aim of this study was to determine the effectiveness of a school dental screening in encouraging school children aged 4 to 6 years to visit a dentist. One thousand five hundred and sixty-two children attending the 13 primary schools in Wallasey. Merseyside, were examined by a single trained examiner; those with urgent treatment needs or evidence of recent treatment were excluded. The remaining 528 children with signs of dental caries were entered into the study. Children within each school were stratified by age, sex and number of carious teeth and then allocated at random to test and control groups. Parents of children in the test group were advised by letter that their child would benefit from a more detailed clinical examination. A reply slip was attached to the letter and non-responders were carefully followed up. The control group received no such interventions. After 4 months, data on dental visits by both test and control group children were extracted from clinical records. Attendance data were obtained for 262 children (97 per cent) in the test group and 243 children (94 per cent) in the control group. Seventy-three per cent of the test group and 42 per cent of the control group visited the dentist over the review period; the difference of 31 per cent favour of the test group was statistically significant. Attendances at both general dental practitioners and community dental clinics were increased. The effect of the screening procedure was seen particularly in areas of lower socio-economic status.(ABSTRACT TRUNCATED AT 250 WORDS)


Evaluation of the World Health Organisation pathfinder methodology for oral health surveys in industrialised countries. The aim of this study was to carry out a survey using the pathfinder methodology developed by the World Health Organisation for international surveys and to compare the results (DMFT, DT, MT, FT) with those obtained from a national survey in France. The statistically significant difference observed between the results of the DMFT and DT indices obtained by using the two methods does not affect the classification of France at the 'moderate' level on the World Health Organisation scale for caries prevalence at the age of 12 years. The observed DMFT difference is an argument in favour of using the World Health Organisation pathfinder methodology, as it provides a satisfactory degree of precision on the oral health status of a population for planning purposes.


The differentiation of sealant restorations from preventive fissure sealants, in subjects with clear sealants. The aim of this study was to assess whether preventive fissure sealants could be differentiated from sealant restorations. The problem of being unable to differentiate between these two tooth states has implications for practitioners and epidemiologists (Davies, 1990). One hundred and seventeen permanent molar teeth, all sealed with a clear sealant, were examined under two types of conditions. These were the Daray 'Versatile light'; mirror, wet teeth, and the Daray 'Operating light 2'; mirror, dry teeth. The subjects' records were subsequently consulted to provide the validating criteria. The results suggest that in a dental hospital environment, when a clear sealant material is in place, it is possible to differentiate between preventive fissure sealants and sealant restorations. It would seem, however, that the 'sealant-alone' variety of sealant restoration was the one most often mistaken for a preventive fissure sealant. The different examination conditions did not markedly affect the examiners' ability to differentiate between the two tooth stage.


The effectiveness of the yellow card warning system for paediatric cardiology patients. Questionnaires were completed by the parents of 100 children with cardiac problems attending the regional paediatric cardiology clinic in Yorkshire. The parents' possession and knowledge regarding the use of a yellow card (warning parents and dentists of the need for antibiotic cover before certain dental treatment) was assessed. Only 57 per cent of parents reported that they had received a yellow card.


Postgraduate prosthetic training within the community dental service. There is a need for clinical prosthetics training for community dentists. This was apparent when a postgraduate course, which dealt with prosthetic care of elderly people, was organised for dentists working in the community dental service. Over 100 community dentists applied for 40 places. At the outset they were asked to complete a questionnaire which addressed their professional career together with their current prosthetic experience. The majority of participants were employed at dental officer level; 18 per cent were at senior dental officer level. Many of the dentists worked in districts where one or more community dentists provided all the prosthetic treatment within the community dental service. The majority of districts receive their prosthetic patients as a result of referrals from a variety of sources. Only eight dentists saw the majority of their patients at domiciliary visits; many did not see any patients in this manner. The course participants considered that their greatest clinical weakness in prosthetic skills was in the production of copy dentures and in denture design. Many of the dentists who attended the course did not provide a prosthetic service but most of them said that they anticipated that the necessity for this would increase in the future.


Factors confounding genetic linkage between atopy and chromosome 11q. The results of testing for linkage between atopy and the chromosome 11 marker D11S97 is shown for all the 723 subjects genotyped by us up to January 1992. Lod score estimations were confounded by the high population prevalence of atopy, maternal inheritance of atopy at the 11q locus, genetic heterogeneity, and excess of atopy in families not ascertained through a single proband. Affected sib-pair analysis shows evidence for linkage which is not dependent on the definition of atopy or model specification. We suggest that presentation of sib-pair data will be suitable for meta-analysis of the different studies of genetic linkage and atopy.


Lack of linkage between atopy and locus 11q13. Atopy as defined in terms of IgE responsiveness was reported to be controlled by a single gene in British families, and this concept was further supported by a significant linkage between atopy and restriction fragment length polymorphism (RFLP) detected by a DNA probe specific to chromosome 11q13. To confirm this observation in a Japanese population, segregation and linkage analyses were done in four large families. Although segregation patterns of atopy were in agreement with the pattern of autosomal dominant inheritance, there was no significant linkage between atopy and locus 11q13. Alterations in the definitions of atopy did not affect the results. These findings suggested the presence of heterogeneity in genetic elements of atopy, even though atopy may be determined mainly by a single dominant gene.


Genetic analysis of atopy in three large kindreds: no evidence of linkage to D11S97. Both genetic and environmental influences have been implicated in the pathogenesis of atopic disease. A recent report suggested that a major gene providing susceptibility to atopy was transmitted in a pattern consistent with autosomal dominant inheritance and evidence was presented that places the disease locus near the D11S97 marker on human chromosome 11q. In this report, we present three large, highly characterized pedigrees in which atopy is transmitted in a pattern consistent with autosomal dominant inheritance. Genotypes at the D11S97 and HLA loci were evaluated using both lod score and sib pair methods of analysis. In these pedigrees, we reject close moderate linkage (up to 10 cM) of atopy with both D11S97 and HLA.


Atopy and bronchial hyperresponsiveness: exclusion of linkage to markers on chromosomes 11q and 6p. Previous studies have reported a familial predisposition for the development of atopy, bronchial hyperresponsiveness and clinical asthma, and therefore have suggested the presence of a heritable component to these disorders. The specific contributions of genetic and environmental factors in the pathogenesis of allergic disease and asthma have not been determined although Cookson et al. [1] have postulated linkage between atopy and chromosome 11q. We have studied 20 families (two and three generations) ascertained through a proband identified as having asthma (90% were also allergic) during the period of time between 1962 and 1970. Of those who were originally skin test positive, 82% remained positive. All probands whose pulmonary function allowed retesting (FEV1 > 1.2 l) remained hyperresponsive to histamine. The children of these probands are now in the same age range as their parents when they were originally evaluated; 66% are atopic using criteria described by Cookson et al. (one or more positive skin tests > or = 2 mm, an elevated total serum IgE or a positive specific IgE) and 22% demonstrate bronchial hyperresponsiveness (PC20 FEV1) to histamine. Using the highly polymorphic marker INT2 (which maps 2 cM from p lambda MS.5 l on chromosome 11q) and atopy, we obtained a lod score of -2.00 at a recombination fraction of 0.12. In addition, because many studies have suggested an association between atopy and certain HLA antigens, we investigated the possibility of linkage between atopy and bronchial hyperresponsiveness and D6S105, a polymorphic marker on chromosome 6p, located 7 cM from HLA-DR. For this marker and atopy, we observed a lod score of -2.00 with a recombination fraction of 0.07.(ABSTRACT TRUNCATED AT 250 WORDS)


Genetic 'risk' for atopy is associated with delayed postnatal maturation of T-cell competence. Recent in vitro studies suggest that IgE production in adults is co-ordinately regulated by negative signals from gamma IFN-producing CD4+ T-helper-1 (TH-1) and positive signals from IL-4 producing (TH-2) T-cells. Additionally, seroepidemiological evidence has pinpointed infancy as the period of maximum lifetime risk for T-cell sensitization to ubiquitous environmental antigens. The present study sought to elucidate the relationship between these observations, by examination of CD4+ T-cell function in normal children and those genetically at 'high risk' for atopy, spanning the age range (up to 4 years) in which IgE responses to environmental allergens is typically manifest. Immunocompetent T-cell precursor frequencies (determined by cloning at limiting dilution) were markedly reduced in 'high risk' children relative to normals (0.53 +/- 0.29 vs 0.26 +/- 0.19; P = 0.0025). Consistent with reports from other laboratories employing bulk T-cell culture techniques, the gamma IFN producing capacity of CD4+ T-cell clones from both groups of children were markedly reduced relative to adults, and was lowest in the high risk group (P < 0.02). IL-4 production by CD4+ T-cell clones from the normal children was within the adult range, but again was significantly lower in the high risk group (P < 0.00005). This indicates that initial immune responses to environmental allergens in early childhood occur against a background of maturational 'deficiency' in CD4+ T-cell function, and suggests the possibility that variations in the rate of postnatal maturation of T-cell competence may be a contributing factor in the development of differing patterns of immunological responsiveness to environmental allergens.


Regulation of IgE production in pre-sensitized animals: in vivo elimination of alveolar macrophages preferentially increases IgE responses to inhaled allergen. Intratracheal inoculation of dichloromethylene diphosphonate encapsulated in liposomes leads to the rapid accumulation of this drug in alveolar macrophage (AM) phagolysosomes, and the death of the majority of these cells over the ensuing 24-48 hr. The technique is highly selective for phagocytes and has no detectable side-effects on other cells in the lung. The present experiments demonstrate that following AM depletion, pre-sensitized animals respond to aerosol challenge via secondary serum IgE (but not IgG) responses, and the accumulation of large numbers of allergen-specific and non-specific antibody forming cells in respiratory tract regional lymph nodes and in lung and airway tissues; the latter comprise both IgE and IgG plasma cells, which were detected in the approximate ratio of 2.5:1. Moreover, aerosol challenged AM-depleted animals develop large mononuclear cell infiltrates in the lung and airways, which includes a substantial CD4+ T-cell component. These results suggest a major role for AM in regulating the magnitude of secondary IgE responses to inhaled allergen.


Congenital high flow coronary cameral fistula in an 81-year-old woman: management problems. An 81-year-old woman presenting with severe congestive heart failure was found to have a congenital right coronary fistula draining into the superior vena cava. The diagnosis was suspected on transthoracic two-dimensional echo-Doppler study and confirmed with coronary angiography. Transesophageal echocardiography and magnetic resonance imaging were nondiagnostic. An attempt to close the fistula with transcatheter embolization using a detachable latex balloon was unsuccessful because of the very large size of the fistula. Follow-up showed a favorable outcome with medical therapy. Despite the advent of more recent diagnostic and therapeutic techniques, management of such large fistulae remains unresolved.


Regression growth evaluation statin study (REGRESS): study design and baseline characteristics in 600 patients. The REGRESS Research Group. To assess the effects of lipid lowering, using a hydroxymethyl glutaryl coenzyme A reductase inhibitor (pravastatin) in symptomatic men with coronary artery disease. To assess follow-up intervention modes and baseline cardiovascular risk factors in men after routine diagnostic coronary arteriography which showed a significant stenosis (at least 50%) in a major segment. Baseline characteristics are stated in a multicentre, prospective, double-blind, randomized, placebo-controlled trial entitled 'regression growth evaluation statin study' (REGRESS). Seven university hospitals and four referral hospitals in The Netherlands. The baseline characteristics are given for the initial 600 patients who entered the REGRESS trial. All patients were 'normocholesterolemic' and suffered from symptomatic coronary artery disease. Initial follow-up treatment was analyzed after coronary arteriography, in accordance with standardized clinical practice (angioplasty, bypass grafting or medical management only). In contrast to routine procedures, 44% of the patient population was found in the medical management only stratum, whereas 32% was found in the coronary bypass graft and 24% in the percutaneous transluminal coronary angioplasty stratum. No major coronary cardiovascular risk factor could explain the decision to perform a certain follow-up intervention. Overall patients showed a low serum high density lipoprotein (HDL) cholesterol level. A higher New York Heart Association classification for anginal complaints tended to favour a more aggressive follow-up approach. The total REGRESS population showed relatively low HDL cholesterol blood levels compared with the general Dutch population. The rationale to perform a specific follow-up intervention by the treating cardiologist is unclear. Severity of anginal complaints may lead to a more active intervention procedure.


Functional capacity of patients with atrial fibrillation and controlled heart rate before and after cardioversion. To measure exercise duration (which frequently is diminished by atrial fibrillation) and to compare the gain in exercise duration achieved by heart rate control with the gain after cardioversion. Eighteen patients (10 with structural heart condition and eight with lone atrial fibrillation) did the treadmill exercise stress test using the Bruce protocol. Resting supine heart rate was lowered below 100 beats/min by verapamil (initial exercise stress test). An exercise stress test was then repeated as often as needed to achieve 'heart rate control' (less than 130 beats/min at the end of a 3 min walk at 10 degrees elevation and 2.74 km/h speed). This heart rate control was obtained by gradual increases in verapamil dose. Subsequently, the patients were converted to normal sinus rhythm chemically (seven patients) or electrically (11 patients) and an exercise stress test was repeated. At cardioversion, patients were on antiarrhythmic therapy and verapamil was discontinued in most. All patients had left atrial size measured by echocardiogram before and after cardioversion, and all were followed for four months. Upon achieving controlled heart rate, exercise duration increased in 16 patients (average gain was 164 s). After cardioversion to normal sinus rhythm, exercise duration further increased in 13 cases with an average additional gain of 90 s. The total increase in exercise duration after cardioversion was 254 s. Post cardioversion, all patients with lone atrial fibrillation improved. A decline in exercise performance occurred in four patients with fixed cardiac output. Average gain in exercise duration was independent of drugs used. Left atrial size remained increased post cardioversion (50.4 mm before and 52 mm after). During four months of follow-up, only eight patients could continue on the same medication given for cardioversion. Three patients did not maintain normal sinus rhythm. Conversion to normal sinus rhythm in patients with atrial fibrillation is associated with improved exercise tolerance except in cases with fixed cardiac output. Restoration of mechanical atrial function appears to be responsible for improved exercise performance following cardioversion.


The internal logic of the Canadian Cardiovascular Society scale for grading angina pectoris: a first appraisal. To assess the internal logic (content validity) of the Canadian Cardiovascular Society (CCS) scale for grading angina pectoris. Forty-one consenting patients with stable angina of at least two months duration, admitted to a tertiary centre for coronary angiography. Patients completed a supervised questionnaire with closed-ended questions. Key questions included: usual numbers of blocks walked on the level or flights of stairs climbed before onset of chest pain; frequency with which chest pain occurred at the usual threshold distance; presence of rest pain; and influence of modifiers suggested for class II of the scale such as walking uphill and into the wind. Agreement of four questionnaire-defined 'stair-climbing grades' and 'walking grades' was statistically significant (P < 0.001) but only 37% better than expected by chance alone (weighted kappa). Frequency of angina at a patient's self-defined exercise threshold varied; only 22 of 41 patients (54%) had symptoms always or often. Higher classes of angina were more likely to be associated with frequent symptoms at threshold, eg, class I/II, six of 23 versus class III/IV, 16 of 17; 2P = 0.00002). Pain at rest was reported as 'definitely' present by 23 of 41 patients, and was similar in incidence across angina classes. All suggested modifiers reduced distances walked in a significant majority of patients (P values uniformly < 0.01) except for walking in the first few hours after awakening. However, the proportions of subjects for whom these factors were relevant were statistically similar for all angina grades, rather than for class II patients alone. These findings suggest that internal inconsistencies in the CCS scale are identifiable with simple validity checks. Further research appears warranted to improve this popular and useful clinical tool.


Analysis of responses to big endothelin in the hindquarters vascular bed of the cat. To investigate vascular responses to the endothelin-1 (ET-1) precursor, human big endothelin 1-38 (big ET), in the peripheral vascular bed of the cat. These studies were designed to investigate the hypothesis that bit ET is converted to an active peptide with properties similar to ET-1. Hindquarters vascular bed of the cat under conditions of controlled bloodflow; changes in perfusion pressure reflect changes in vascular resistance. Fifty-four adult mongrel cats. Big ET, ET-1, the peptidases chymotrypsin, pepsin and cathepsin-D, and the metalloprotease inhibitor phosphoramidon. Intra-arterial injections of big ET induced a slow-developing and sustained increase in hindquarters perfusion pressure which could be blocked by phosphoramidon. ET-1 (0.3 nmol), administered as a slow infusion over a 10-min period, produced a slowly developing increase in hindquarters perfusion pressure in a manner similar to that observed in response to injection of big ET. A bolus injection of ET-1 produced a biphasic response characterized by a transient decrease in pressure followed by an increase which was significantly greater in magnitude and more rapid in onset than the pressor response to big ET (0.3 nmol). After incubation of big ET with chymotrypsin, pepsin and cathepsin-D (each 5% weight/weight) for 30 mins at 37 degrees C, injection of activated big ET produced a biphasic response characteristic of the response to ET-1 with an initial transient decrease in pressure followed by a secondary increase in hindquarters perfusion pressure. Big ET produces a phosphoramidon-sensitive pressor response which is similar to that produced by an infusion of ET-1. These data suggest that chymotrypsin, pepsin and cathepsin-D can convert big ET to an active peptide which elicits a biphasic response similar to that produced by ET-1.


Phenomenon of the adaptive stabilization of structures and protection of the heart. To study the role of heat shock proteins in the mechanism of adaptive stabilization of structures. Double-blind randomized trial. Wistar male rats weighting between 250 and 300 g. Adaptation to restraint stress. Animals were heparinized and anesthetized with nembutal. Experiments on isolated heart included ischemia, reperfusion, adrenergic damage and heat shock. Biochemical investigations studied calcium transport from sarcoplasmic reticulum and mitochondria, and cytofluorimetrical analysis of DNA using the O'Farrell method. In reperfusion, the contraction amplitude of the hearts from adapted animals was 8.8 times higher than control. This acceleration of the contractile function recovery was due to a more rapid disappearance of the contracture. The duration of ventricular tachycardia and fibrillation was 246 +/- 16 s in control and 119 +/- 12 s in adaptation (P < 0.001). The creatine kinase release was 719 +/- 34 mU/min/g wet weight in control and 302 +/- 120 mU/min/g wet weight in adaptation (P < 0.05). In adaptation, the heat shock-induced contraction amplitude was 2.4 times higher than control and the enzyme yield was practically absent. Adaptation reduced the duration of atrioventricular blockade from 385 to 233 s per group and decreased the number of extrasystoles by 6.5 times. The calcium leakage from intracellular stores during storage proceeded slower in adaptation than in control. During storage of mitochondria at 4 degrees C, oxygen consumption fell much slower in adaptation than in control. As a result, the capacity of mitochondria (isolated from hearts of adapted animals stored for two days) to consume oxygen was 50% higher than in controls; in controls, almost one-half of nuclei were already damaged at one-chain DNA concentration of 50 micrograms/mL, while this phenomenon was 5.5 times less pronounced in adaptation. Adaptation resulted in the accumulation of five polypeptides (molecular weight 72 kDa and pl from 6.3 to 5.7). The mechanism providing adaptive increase of the heart resistance is apparent both at the central level and at the level of heart cells, and is accompanied by accumulation of inducible polypeptides.


Protective effect of probucol on ischemia-reperfusion arrhythmias in the rat heart. To evaluate the efficacy of probucol on ischemia-reperfusion injury in the isolated working rat heart. Twelve male Sprague-Dawley rats were divided into two groups: one was fed normal chow (group C) and the other was fed chow containing 1% probucol for four weeks (group P). Samples of heart organ and blood were then taken under anesthesia. Isolated hearts were perfused in a working heart model. After 5 mins of perfusion in aerobic conditions, global ischemia was induced for 15 mins, the hearts were then reperfused. Aortic and coronary flow, cardiac function and electrocardiogram were monitored throughout the experiment, including a 20 min period of reperfusion. Serum lipids and lipid peroxide were also measured in each rat. Rats in group P (probucol-treated) had significantly lower levels of serum cholesterol, triglyceride and phospholipid than those in group C (controls). Serum lipid peroxide was also significantly lower in group P than in group C rats (P < 0.05). The incidence of ventricular arrhythmias in the ischemia and reperfusion stages was lower in group P than in group C (P < 0.001) and the increase in coronary flow during the reperfusion stage was greater in isolated hearts of group P rats than in those of group C (P < 0.05). Probucol may have a protective effect on myocardium with respect to ischemia-reperfusion arrhythmia in the isolated rat heart, presumably due to an antioxidative effect.


Effect of exogenous hydrogen peroxide on myocardial function and structure in isolated rat heart. A time- and dose-dependent effect of exogenous hydrogen peroxide was determined on myocardial function, structure, high energy phosphate and lipid peroxidation in the isolated perfused rat heart. Hydrogen peroxide induced a dose-dependent decrease in cardiac function whereas 200 microM hydrogen peroxide reduced +dP/dt to 50% of control value after 10 mins. The effect of 300 microM hydrogen peroxide was more severe after 15 mins; changes observed with this dose were reversible within 10 mins of perfusion, becoming irreversible after 15 mins. Lipid peroxidation and severe morphological damage were observed after 10 mins of perfusion with 300 microM hydrogen peroxide. When 16 mEq potassium ions were added in the perfusion buffer during hydrogen peroxide perfusion, the degree of tissue damage and loss of ATP were attenuated. However, lipid peroxidation was not inhibited by high potassium ions. When 0.25 microM N,N'-diphenyl-1,4-phenylenediamine, a potent antioxidant, was added to the perfusate, lipid peroxidation was totally inhibited and the degree of tissue damage was decreased. However, depletion of tissue ATP and functional deterioration were not influenced. These results suggest that hydrogen peroxide-mediated ATP loss was independent of lipid peroxidation.


Object identification in context: the visual processing of natural scenes. When we view a natural visual scene, we seem able to determine effortlessly the scene's semantic category, constituent objects, and spatial relations. How do we accomplish this visual-cognitive feat? The commonly held explanation is known as the schema hypothesis, according to which a visual scene is rapidly identified as a member of a semantic category, and predictions generated from the scene category are then used to aid subsequent object identification. In this paper I will first outline and offer a critique of the evidence that has been taken to support the schema hypothesis. I will then offer an alternative framework for understanding scene processing, which I will call the local-processing hypothesis. This hypothesis assumes a modular, informationally-encapsulated architecture, and explicitly includes the role of covert visual attention in scene processing.


Eye movements and scene perception.

Eye movements and scene perception. Research on eye movements and scene perception is reviewed. Following an initial discussion of some basic facts about eye movements and perception, the following topics are discussed: (I) the span of effective vision during scene perception, (2) the role of eye movements in scene perception, (3) integration of information across saccades, (4) scene context, object identification and eye movements, and (5) the control of eye movements. The relationship of eye movements during reading to eye movements during scene perception is considered. A preliminary model of eye movement control in scene perception is described and directions for future research are suggested.


Parallel pattern processing and visual agnosia. A series of visual search experiments are reported examining pattern processing in a visual agnosic patient. We examined search for targets defined by: (I) the combination of their features relative to homogeneous distractors; (2) the combination of their features relative to heterogeneous distractors; and (3) a single feature difference relative to the distractors (their orientation). Normal subjects demonstrate evidence of spatially parallel search when combined-feature targets are detected against homogeneous distractors, and when targets are defined by a salient feature difference. There are non-linear effects of the number of distractors present, and absent responses can be as fast as present. In contrast, search times for combined-feature targets amongst heterogeneous distractors increase linearly with display size, with the slope for absent responses about twice that for present. The contrast between search for combined-feature targets amongst homogeneous and heterogeneous distractors can be attributed to the effects of grouping between distractors and between distractors and targets (Duncan & Humphreys, 1989, 1992; Humphreys & Muller, in press). Grouping between homogeneous distractors facilitates search. An agnosic patient, HJA, showed normal search functions for single-feature targets and for combined-feature targets amongst heterogeneous distractors. However, he was impaired at search for combined-feature targets amongst homogeneous distractors. This suggests that HJA is selectively impaired at grouping conjunctions of form features. The relations between HJA's agnosia and his problem in the parallel grouping of form conjunctions are discussed, as are the implications of the work for understanding normal vision.


Lesioning a connectionist model of visual search: selective effects on distractor grouping. A connectionist model of visual search is presented, in which search is determined by patterns of grouping between distractors and between the target and the distractors. Grouping is based on conjunctive relations between simple form elements (corners, line-end terminators), and uses principles of similarity and spatial proximity. In its normal, 'unlesioned' state, the model simulates the search data generated by human subjects when they search for simple form conjunctions amongst either homogeneous or heterogeneous distractors (Humphreys & Muller, in press). In this paper, the performance of the model is examined after the model is subject to various types of 'lesion'. 'Lesioning' is produced either by increasing the internal noise on the activation functions governing the interactions between processing units, or by eliminating processing units from different loci in the model. Increasing the internal noise within the model, or lesioning units within 'high-level' processing stages, can generate the selective effects on search found in a detailed single case study of an agnosic patient (Humphreys, Riddoch, Quinlan, Price & Donnelly, this volume): Namely, there is selective disruption of search for a form conjunction amongst homogeneous distractors relative to search for the same target amongst heterogeneous distractors. This selective effect can be attributed to the 'lesion' disrupting grouping between distractors, which normally facilitates search with homogeneous distractors. The simulations demonstrate that (1) search processes can be disrupted by adding internal noise to search functions, (2) that there can be selective effects on grouping processes, and (3) that these selective effects can be associated with different types of lesion to different stages in the model. The implications of the simulations for understanding visual processing impairments in agnosia are discussed.


Solving the "real" mysteries of visual perception: the world as an outside memory. Visual science is currently a highly active domain, with much progress being made in fields such as colour vision, stereo vision, perception of brightness and contrast, visual illusions, etc. But the "real" mystery of visual perception remains comparatively unfathomed, or at least relegated to philosophical status: Why it is that we can see so well with what is apparently such a badly constructed visual apparatus? In this paper I will discuss several defects of vision and the classical theories of how they are overcome. I will criticize these theories and suggest an alternative approach, in which the outside world is considered as a kind of external memory store which can be accessed instantaneously by casting one's eyes (or one's attention) to some location. The feeling of the presence and extreme richness of the visual world is, under this view, a kind of illusion, created by the immediate availability of the information in this external store.


Local and global contextual constraints on the identification of objects in scenes. Objects likely to appear in a given real-world scene are frequently found to be easier to recognize. Two different sources of contextual information have been proposed as the basis for this effect: global scene background and individual companion objects. The present paper examines the relative importance of these two elements in explaining the context-sensitivity of object identification in full scenes. Specific sequences of object fixations were elicited during free scene exploration, while fixation times on designated target objects were recorded as a measure of ease of target identification. Episodic consistency between the target, the global scene background, and the object fixated just prior to the target (the prime), were manipulated orthogonally. Target fixation times were examined for effects of prime and background. Analyses show effects of both factors, which are modulated by the chronology and spatial extent of scene exploration. The results are discussed in terms of their implications for a model of visual object recognition in the context of real-world scenes.


Translocation t(12;22)(q13;q13) is a nonrandom rearrangement in clear cell sarcoma. Cytogenetic analyses of tumor cells from a case of clear cell sarcoma revealed a translocation between chromosomes 12 and 22 that was similar to the rearrangement described recently in three other cases. It is suggested that the translocation may be important in the pathogenesis of this rare tumor.


Significance of both numerical and structural chromosomal abnormalities in clear cell sarcoma. We analyzed cytogenetically two cases of clear cell sarcoma. The t(12;22)(q13;q13) hypothesized to be characteristic of clear cell sarcoma was detected in one of the two cases. Although this translocation was not observed in the other case; trisomy of chromosome 22 was, as were other numerical abnormalities. This latter observation has also been described in other reported studies of clear cell sarcoma. These findings confirm the nonrandomness of t(12;22)(q13;q13) in clear cell sarcoma, but also suggest that in its absence other abnormalities of chromosome 22 are significant. Trisomy 8, noted in both cases we report, as well as in previous studies, also appears to play an important role in clear cell sarcoma.


t(12;22)(q13;q13) and trisomy 8 are nonrandom aberrations in clear-cell sarcoma. We report a case of clear-cell sarcoma with a t(12;22)(q13;q13) and multiple copies of chromosome 8 in addition to other abnormalities. An identical or similar translocation has previously been reported in this type of tumor, suggesting that the t(12;22) is a primary cytogenetic change in the pathogenesis of a subset of clear-cell sarcomas. In addition, the presence of extra copies of chromosome 8, commonly noted in our case and others, suggests that it represents a nonrandom secondary change in these tumors.


Chromosome abnormalities in liposarcomas. We performed a cytogenetic study of short-term cultures from fresh surgical specimens obtained from four patients with liposarcoma. Myxoid liposarcomas (cases 1-3) were associated with a specific translocation between chromosomes 12 and 16. Trisomy 8, a nonrandom secondary aberration in myxoid liposarcoma, was observed in the third case as the only additional change. Round cell liposarcoma (case 4) showed complex chromosomal aberrations affecting chromosomes 1, 2, 5, 6, 7, 13, 14, 17, 19, and 22. Neither band 12q13 nor 16p11 was visibly rearranged. Three subgroups of liposarcomas are proposed. The first group is characterized by t(12;16)(q13;p11), the second group by ring chromosomes, telomeric associations, and giant markers, and the last by complex numerical and structural aberrations.


Preferential chromosome 11q and/or 17q aberrations in short-term cultures of metastatic melanoma in resections from human brain. Thirteen specimens of metastatic malignant melanoma resected from eight patients undergoing craniotomy were analyzed cytogenetically from short-term cultures. All patients had chromosome 1 aberrations, as did three of four patients with metastases only to extracranial sites. Both groups had variable involvement of chromosomes 3, 6, 7, and 8. Only those with brain metastases had 11q and/or 17q involvement in six of eight patients. In reported cases of nonbrain metastases, when chromosome 11 was involved, the short arm was usually deleted or replaced through translocation; on the contrary, in reports on patients with brain metastases, the long arm of chromosome 11 was deleted at q23 or was the recipient of a translocation at q23, and/or 17q was present as an isochromosome. These aberrations were similar to those found in the patients with brain metastases in this report. Two patients undergoing brain resections did not show 11q or 17q aberrations, one near diploid with t(10;19) and the other near hexaploid with few structural rearrangements. The neural cell adhesion molecule gene is located near 11q23, and the neural growth factor receptor is located near 17q21-q22. The relevance of these genes to brain metastases in melanoma is under investigation.


Cytogenetic study of a pineocytoma.

Cytogenetic study of a pineocytoma. The cytogenetic findings based on G-banding in a pineocytoma detected in a 29-year-old woman are reported. The chromosomal study showed numerical alterations involving chromosomes X, 5, 8, 11, 14, and 22, structural alterations of chromosomes 1, 3, 12, and 22, as well as various markers. Tumors of the pineal region are infrequent, and this is the first report of a pineocytoma studied cytogenetically.


Cytogenetic abnormalities in a squamous cell carcinoma of the penis. Cytogenetic findings in a squamous cell carcinoma (SCC) of the penis in a 60-year-old patient was observed for the first time. The stemline karyotype of the tumor was 46,XY,del(2) (q33q36),der(4)t(4;?)(p16;?),der(5;15)(q10;q10),der(8)t(8;?13)(p21 ;?),-13,- 13,-15,+3mar.


Deletion (7)(p11p15) in a patient with Philadelphia-positive chronic myelogenous leukemia. We report a case of chronic myelogenous leukemia (CML) with a Philadelphia (Ph) chromosome. During the transformation phase of the disease, a del(7)(p11p15) and a +Ph were identified as additional chromosomal anomalies. We believe that loss of the segment 7p11-->p15 may play an important role in the progression of the disease.


Fluorescence in situ hybridization to determine engraftment status after murine bone marrow transplant. The mouse Y-specific DNA sequence pY2 was used as a probe for fluorescence in situ hybridization (FISH) to evaluate murine hematopoietic tissues after sex-mismatched bone marrow transplant (BMT). The pY2 probe was localized to the long arm of the Y chromosome on BM metaphases. Hybridization of pY2 in FISH of interphase cells from BM, spleen, and thymus after BMT was compared with Southern blot analysis; both methods gave comparable results. Only FISH was able to analyze post-BMT peripheral blood (PB) samples successfully, and provides a useful method for following engraftment status in the mouse on an ongoing basis.


Specific chromosomal defects associated with ultraviolet radiation-induced cutaneous tumors in Monodelphis domestica (Marsupialia, mammalia). Cytogenetic analysis of eight ultraviolet radiation (UVR)-induced cutaneous tumors and one spontaneously transformed fibroblast cell line of Monodelphis domestica showed that two of the tumor cell lines were of murine origin and that the remaining six marsupial tumor cell lines had hyperdiploid stemline numbers ranging from 21 to 31. Each tumor cell line showed structural and numerical abnormalities. The single transformed fibroblast cell line also showed a hyperdiploid chromosome number with structural and numerical defects. All M. domestica tumor cell lines and the fibroblast line showed a common structural abnormality: deletion of the short arm (p) of a chromosome 1. In some cell lines, the short arm of chromosome 1 was replaced by a translocation with the X chromosome. We suggest, based on the Giemsa-banding homology of chromosome 1p in M. domestica and human chromosome 6q involved in melanomas, that marsupial chromosome 1p may harbor tumor suppressor gene(s) that are associated with UVR-induced cutaneous tumors.


Supernumerary ring marker chromosome as a secondary rearrangement in a parapharyngeal lipoma with t(10;12)(q25;q15) as the primary karyotypic abnormality. Cytogenetic analysis of a large parapharyngeal lipoma, a rare tumor at this site, showed the karyotype 46,XY,t(10;12)(q25;q15)/47,XY,t(10;12)(q25;q15),+r. The primary abnormality must have been t(10;12), whereas the +r developed secondarily as an additional aberration. Although a similar translocation between chromosomes 10 and 12 has not been described previously, that the tumor had a rearrangement of the 12q13-15 region, the most frequently involved genomic region in lipogenic tumors, indicates that the tumorigenetic mechanisms are identical in parapharyngeal lipomas and lipomas of other locations. Supernumerary ring markers are not usually detected in lipomas with 12q rearrangements but are common in atypical lipomas and well-differentiated liposarcomas. The parapharyngeal lipoma we describe recurred after initial resection, and we hypothesize that the more aggressive tumor phenotype thus demonstrated may be causally related to the clonal evolution it had undergone.


A lineage-specific t(1;14)(q21;q32) as an early event in development of B-cell clonal expansion. We report a patient in whom a cell line of 47,XY,+X,t(1;14)(q21;q32) constitution was found in a lymph node excised from the neck. Histologic examination and immunophenotyping both in situ and by flow cytometry failed to confirm a diagnosis of B-cell lymphoma, but Southern analysis indicated the presence of B-cell clonal expansion. These observations support the concept that primary chromosomal abnormalities occur in clonal expansions in the very earliest stages of tumorigenesis.


Karyotypic analysis of gastric carcinoma cell lines carrying an amplified c-met oncogene. MKN 45 is a poorly differentiated gastric carcinoma cell line from which the subclone GTL 16 was obtained. Both lines carry an amplification unit derived from chromosome 7 sequences and containing an activated c-met oncogene. Karyotypic analysis showed that GTL 16 derived from a subclone of MKN 45 after endoreduplication. Several clonal abnormalities are evident in both lines; some are frequently observed in gastrointestinal tumors (loss of 17p and monosomy 18). Other consistent anomalies include 6q-, t(8;10) and t(5;8), and inv(16). A marker chromosome (M1), which was previously shown to contain the c-met amplification unit, is constantly duplicated in all GTL 16 metaphases; in contrast, most unidentified markers are retained in only a single copy in GTL 16 cells. These data are in agreement with the hypothesis that the c-met oncogene activation in these gastric cancer cell lines might be related to a gene dosage effect.


Disappearance of a highly unusual clone, 46,XY,del(7)(p12),t(9;22)(q34;q11) in chronic myeloid leukemia after treatment with recombinant interferon and cytosine arabinoside. A patient with the typical features of the stable phase of chronic myeloid leukemia (CML) displayed two karyotypically related subclones. In addition to the t(9;22), cells from one clone contained a deletion of the short arm of chromosome 7, del(7)(p12), [46,XY,del(7)(p12),t(9;22)(q34;q11)]; the other contained only the standard translocation [46,XY,t(9;22)(q34;q11)]. Cells with a deletion of the short arm of chromosome 7 at band p12 as the only additional abnormality have not been observed previously in CML. Conventional chemotherapy with hydroxyurea and then with recombinant interferon-alpha (rIFN-alpha) did not reduce the population of either subclone. However, after treatment with a combination of rIFN-alpha and low-dose cytosine arabinoside (LoDac) continuously infused subcutaneously (s.c.), cells from the clone with the deleted chromosome 7 disappeared and normal metaphases were demonstrable.


Translocations (17;20) in colorectal adenocarcinomas. We describe new recurrent chromosome translocations (17;20) observed in 3 of 19 colorectal tumors. Two of them were identical: der(20)t(17;20)(q21;p12), resulting in the loss of 17(pter-->q21) and the third was a dicentric dic(17;20)(p11;p12). A similar dicentric was described previously in one tumor [1], but we report der(20)t(17;20)(q21;p12) for the first time.


Confirmation of centromeric fusion in 7p/1q translocation associated with myelodysplastic syndrome. Fluorescence in situ hybridization (FISH) using chromosome 1- and chromosome 7-specific centromeric alpha-satellite probes was performed on the bone marrow (BM) cells of a patient with myelodysplastic syndrome (MDS) who had been treated for lymphoma and whose BM karyotype was initially considered to be 46,XY,-7,+der(1)t(1;7)(p11;p11). FISH results suggested the presence of both chromosome 1 and chromosome 7 centromeres in the rearranged chromosome. Thus, the correct karyotype should be written as 46,XY,-7,+der(1;7)(q10;p10).


[The angiographic evaluation of elastic recoil after coronary angioplasty]. Coronary angioplasty is an effective recanalization technique, but is plagued by a high restenosis rate. One of the major effects of balloon dilatation is the stretching of the vessel wall and the subsequent elastic recoil. Although a well known phenomenon, few data have been published on the evaluation of elastic recoil after coronary angioplasty. The purpose of this study was to quantify the acute and short-term elastic recoil after coronary dilatation. Thirty-six patients underwent coronary angioplasty. A digital end-diastolic acquisition of the coronary artery was performed before, immediately after, at 15 min and at 20 hours after dilatation. Elastic recoil was defined as the difference between the diameter of the inflated balloon and the diameter of the vessel after dilatation. It was quantified by a semi-automatic computer-assisted program. Our data show a high elastic recoil immediately after dilatation, equal to 27.9% (p < 0.0001), which continues for the next 20 hours to a final value of 34.1%. No difference was found in the amount of elastic recoil depending on the coronary artery involved, length, severity and eccentricity of the stenosis, time and pressure used during balloon inflation. Elastic recoil was more pronounced (p = 0.002) using balloons with a balloon diameter/vessel diameter ratio > 1.


[The clinical and prognostic significance of symptomatic and silent ischemia on the exercise test in patients with a prior myocardial infarct]. The aim of the study was to assess clinical/prognostic significance of exercise-induced ischemia in patients with healed myocardial infarction. From May 1988 to January 1991, 777 consecutive patients underwent a symptom-limited (Bruce protocol) treadmill test at least 1 year after myocardial infarction. Clinical and ergometric data were entered in a prospective way in our data base. The exercise-test was positive in 231 out of 777 patients and 2 different subgroups were retrospectively identified depending on criteria of interruption: 156 patients with painless exercise-ST depression; 75 patients with painful exercise-ST depression. The main results (mean +/- SD) were analyzed with Student t test and chi 2 test. Patients with silent ischemia had longer exercise duration (547 +/- 153 s versus 395 +/- 173 s; p < 0.001) and higher double product (22.98 +/- 0.5 versus 19.71 +/- 0.4; p < 0.001) than symptomatic patients. Ischemic threshold was lower (double product: 17.98 +/- 0.4 versus 21.22 +/- 0.4; p < 0.001 with onset of ST depression at 297 +/- 148 s versus 448 +/- 147 s; p < 0.001) and time to ST normalization was longer (368 +/- 155 s versus 234 +/- 212 s; p < 0.001) in patients with painful ischemia. Patients with angina and ST depression had significantly higher prevalence of downsloping ST depression in the recovery phase (68% versus 37%; p < 0.001) and a higher prevalence of treadmill exercise score indicating high risk (49% versus 3.2%; p < 0.001). The 2 groups when compared with 99 patients with negative test post-AMI were significantly different.(ABSTRACT TRUNCATED AT 250 WORDS)


[The effect of nifedipine on arterial pressure and exercise tolerance in hypertensive patients]. The aim of this research was to assess whether the antihypertensive therapy with nifedipine, a dihydropyridine calcium-antagonist, is able to control hypertension not only at rest but also during exercise. So, 20 male hypertensive patients, mean age 48 years, were evaluated by symptom limited bicycle exercise (10 W/min) before and after 6 and 12 months of therapy with nifedipine in a slow releasing form (40-60 mg/day). Exercise tolerance significantly increased after 12 months of antihypertensive therapy with nifedipine (from 146 +/- 5 to 153 +/- 4 W, p < 0.05). Systolic and diastolic blood pressure decreased after 6 and 12 months both at rest (from 160 +/- 6/109 +/- 9 mmHg to 132 +/- 3/91 +/- 3 and 135 +/- 4/93 +/- 1 mmHg, respectively, both p < 0.001) and during exercise (at end exercise: from 238 +/- 7/121 +/- 5 mmHg to 216 +/- 6/106 +/- 3 and 213 +/- 6/107 +/- 3 mmHg, respectively, both p < 0.001). No significant changes in heart rate were observed during antihypertensive therapy both at rest and during exercise test. In conclusion, long-term antihypertensive therapy with nifedipine was effective in the control of hypertension both at rest and during physical stress. Moreover, an improvement in effort tolerance was observed in hypertensive patients.


Integrated ultrasound evaluation of dissecting aneurysm of the aorta by the combined use of transesophageal echocardiography and intravascular ultrasound. In order to obtain complete ultrasound imaging of the entire aorta, transesophageal echocardiography and intravascular ultrasound were performed on 3 patients with acute (2 cases) or chronic (1 case) aortic dissection. In each case the integrated use of transesophageal echocardiography and intravascular ultrasound provided an accurate evaluation of the dissection and of its anatomic extension.


[Postendocarditis aneurysm of the right sinus of Valsalva: its echographic diagnosis with preoperative angiographic confirmation]. The sinus of Valsalva aneurysm is a rare complication of bacterial endocarditis in infancy and childhood. This report describes a young man with congenital aortic stenosis and bacterial endocarditis caused by Salmonella typhi. Bacterial endocarditis in this young man was complicated by the development of an aneurysm of the right sinus of Valsalva and a severe aortic regurgitation. Two-dimensional and Doppler echocardiography proved useful for the initial diagnosis and serial follow-up of this unusual disorder. However, an angiographic examination has been necessary for the surgical correction in order to understand the relationship between the aneurysm and the coronary arteries.


[The effect of vasoactive factors on the growth of of coronary endothelial cells]. The aim of this study was to evaluate the effect of adenosine and bradykinin on endothelial cell growth at capillary level. DNA synthesis was measured in subconfluent capillary endothelial cells obtained from coronary venules (CVEC) after exposure to adenosine or bradykinin. Our results indicate that adenosine and bradykinin induced a dose-dependent proliferation of CVEC. Maximal effect was observed at the dose 100 microM concentration for adenosine and 0.1 microM concentration for bradykinin.


[The evaluation of the end-ejection pressure-length relation as an index of regional contractility]. Although end-systolic pressure-length relationship (ESPLR) is now widely used as a regional substitute for the end-systolic pressure-volume relationship, there are some reservations about its use as an index of systolic performance. This study aimed at assessing whether by using end-ejection (zero aortic flow) as a definition of end-systole, ESPLR can be used to characterize myocardial performance independent of load, and if the choice of the region where to implant the sonomicrometers is critical. Ten anaesthetized dogs (16 +/- 2 kg) were instrumented with a left ventricular (LV) pressure micromanometer and an aortic flow probe. Sonomicrometers were implanted in the apical (L1) and the mid-ventricular (L2) regions of the anterior LV wall, and in the basal region of the lateral wall (L3). End-systolic pressure-length relationships were obtained during acute preload reduction induced by the inflation of a vena caval balloon. This evaluation was repeated after increasing end-diastolic pressure to 14-18 mmHg (delta PL), after increasing systolic pressure by 15 (delta P-I) and 25 mmHg (delta P-II) with graded descending aorta occlusion, and during dobutamine infusions at 2.5 (Db 2.5) and 5 micrograms/kg/min (Db5). End-systolic pressure-length relationships (r > 0.97; pressure range: 70-100 mmHg) were characterized by their slopes (Ees), the extrapolated intercept at zero pressure (L0) and the values of segment length at a pressure of 75 (L75) and 100 mmHg (L100). In all the myocardial regions studied by sonomicrometry, the increments in preload and afterload did not significantly shift ESPLR.(ABSTRACT TRUNCATED AT 250 WORDS)


[A mathematical model of the vascular architecture and of the distribution of resistances in the coronary tree]. The architecture and resistance distribution of the coronary arteriolar tree downstream 100 mu diameter vessels are still largely unknown, due to technical difficulties in direct visualization. In this study we propose a mathematical model of the architecture and the single vessel resistance distribution of terminal arteriolar vasculature in the beating dog heart, based on the analysis of embolization-induced changes of total coronary resistance. Coronary embolization was performed by injecting several boluses of 15 mu (6 cases) and 25 mu (6 cases) plastic microspheres into the maximally vasodilated (adenosine infusion) left circumflex artery of the open chest dog. The relation between the number of plastic beads progressively injected to embolize 15 mu and 25 mu vessels and the resulting increase in total coronary resistance (occlusion function) was obtained in each experiment. If we consider a binary symmetric vascular tree with i) equal resistance for vessels of the same branching order and ii) optimal ratio between resistance of parent and daughter vessels at all branching sites, the simulation of embolization in such a system shows that the occlusion function of the terminal vessels N in the linear portion between 0 and N/2 occluded vessels has a slope S' which is 5.6 times lower than the slope S" between N/2 and 3/4 N occluded vessels and 3.6 times lower than the S' of the occlusion function of the preterminal vessels. The occlusion function in our experiments has a ratio S"/S' close to that predicted by the model and a ratio between the S' of the 25 mu and that of 15 mu experiments equal to 4.(ABSTRACT TRUNCATED AT 250 WORDS)


[Acidosis is associated with an intracellular accumulation of Ca2+. Its role in the modulation of myocardial contractility]. Myocardial acidosis, as during ischemia, profoundly modifies excitation-contraction mechanisms. The decreased myofilament sensitivity to Ca2+ reduces contractility regardless of an intracellular accumulation of Ca2+. To determine the source for this increase in Ca2+ we evaluated the effect of acidosis on diastolic [Ca2+] and mitochondrial [Ca2+]. We used single cardiac cells loaded with the fluorescent probes, indo-1 for Ca2+ and SNARF-1 for pH. Acidosis increases [Ca2+] both in cytosol and mitochondria. The cytosolic accumulation depends, most likely, on an active release from mitochondria. A competition among Ca2+ and H+ ions may, instead, explains the increase in mitochondrial [Ca2+].


[Myocardial protection in hypothermia depends on the modulation of intracellular Ca2+ homeostasis]. The effect of a mild hypothermia (30 degrees C) on sarcoplasmic reticulum (SR) Ca2+ content and release has been evaluated in single cardiac cells loaded with the fluorescent indicator, indo-1. SR Ca2+ content, assessed by rapid caffeine application, is more pronounced at 30 than at 37 degrees C. However, hypothermia reduces the occurrence of spontaneous SR Ca2+ oscillations. In fact, following electrical stimulation, the time to onset of first SR Ca2+ oscillation was increased and their frequency reduced. Since spontaneous SR Ca2+ releases are implicated on the genesis of certain forms of ventricular arrhythmias, the protection provided by a mild hypothermia may be dependent on the modulation of intracellular Ca2+ homeostasis.


Effect of supranormal coronary blood flow on energy metabolism and systolic function of porcine left ventricle. The goal was to determine if supranormal coronary blood flow increases myocardial oxygen consumption, high energy phosphate levels, and systolic function in the in situ autoperfused heart. Thirteen anaesthetised open chest pigs with an intact, autoperfused coronary circulation, weight 30-40 kg, were studied. Measurements were made under basal conditions and during regional hyperperfusion of the anterior left ventricle produced by intracoronary infusion of adenosine (mean dose 3.3 mumol.min-1). Doppler coronary blood flow velocity in the anterior descending coronary artery, arterial and anterior interventricular venous blood oxygen content, high energy phosphates (by transmurally localised 31P NMR), and myocardial wall thickening (by sonomicrometry) were measured. With adenosine, coronary flow was increased to 355(SEM 59)% of control. Supranormal coronary flow produced no significant changes in anterior left ventricular oxygen consumption [99(12)% of control]. 31P NMR spectroscopy revealed no significant changes in the peak intensities of phosphocreatine or ATP in either the subendocardium or subepicardium (90-97% of control). Systolic anterior left ventricular wall thickening also did not change [107(13)% of control]. Supranormal coronary flow does not augment myocardial oxygen consumption, high energy phosphates, or systolic function in the in situ autoperfused heart. Myocardial oxygen delivery does not limit oxidative metabolism under normal conditions.


Regulation of tissue noradrenaline in the rat myocardial infarction model of chronic heart failure. The aim was to evaluate mechanisms regulating tissue noradrenaline in congestive heart failure. Tissue noradrenaline was measured in the conscious post myocardial infarction rat model of congestive heart failure and in sham operated rats (1) under control conditions, (2) 6 h after inhibition of tyrosine hydroxylase by the intraperitoneal administration of alpha-methyl-para-tyrosine (AMPT) (100 mg.kg-1 every 2 h), (3) 6 h after AMPT with desipramine pretreatment (0.3 mg.kg-1), and (4) following exhaustive exercise after AMPT. Tissue noradrenaline was extracted with perchloric acid and measured by high performance liquid chromatography with electrochemical detection. In control animals without drug, tissue noradrenaline concentration was lower in the following tissues in the rats with myocardial infarction compared with the sham operated group: left and right ventricles, spleen, soleus and white gastrocnemius muscles, kidney cortex, and tail artery. After AMPT, tissue noradrenaline concentration in the sham operated group was significantly lower than control; in the myocardial infarction group the fall in noradrenaline was only significant in the kidney, and group differences were no longer present. In the sham operated animals, coadministration of desipramine with AMPT attenuated the fall in tissue noradrenaline caused by AMPT in the heart and spleen. With exercise to exhaustion, cardiac noradrenaline was lower in rats with myocardial infarction than in sham operated rats, but higher in the soleus muscle. These data suggest that tissue noradrenaline depletion in congestive heart failure is not isolated to the heart, and it occurs despite activation of mechanisms that might be operating to conserve neuronal noradrenaline. One mechanism may be reduced organ blood flow to retard diffusion of noradrenaline into the circulation. If this increases interstitial noradrenaline concentration, it would facilitate prejunctional alpha 2 receptor restraint on noradrenaline release. Metabolic coronary vasodilatation during exercise reverses this process, and makes the heart most susceptible to noradrenaline depletion in congestive heart failure.


Effect of intravenous adenosine on human atrial and ventricular repolarisation. The aim was to assess the effects of therapeutic doses of intravenous adenosine on human atrial and ventricular repolarisation. The effects of 6 mg and 12 mg bolus doses of adenosine on the atrial and ventricular monophasic action potentials were studied using the contact catheter technique in 19 patients undergoing routine diagnostic electrophysiology studies. The effect on atrial repolarisation was studied before and after beta blockade in a subgroup of patients. The duration of the monophasic action potential to 90% repolarisation (MAPD90) was measured in all cases. After 6 mg of adenosine the atrial MAPD90 shortened from 227(SD 29) ms to 188(25) ms (p < 0.005); after 12 mg it shortened from 221(31) ms to 168(32) ms (p < 0.001). The maximum shortening was unaltered by propranolol 0.15 mg.kg-1. The ventricular MAPD90 showed no significant change after 12 mg, at 240(32) ms v 234(33) ms. Therapeutic doses of adenosine shorten the atrial but not the ventricular monophasic action potential duration. The effect is dose dependent and not abolished by beta blockade.


Stimulus-response curves for hypoxic pulmonary vasoconstriction in piglets. The aim was to characterise stimulus-response curves for hypoxic pulmonary vasoconstriction and to observe the effects of drugs reputed to enhance it: aspirin (a cyclo-oxygenase inhibitor), and doxapram (a peripheral chemoreceptor agonist). Mean pulmonary artery pressure (Ppa) versus fraction of inspired O2 (FIO2) relationships were studied in 18 intact anaesthetised piglets, before and after the intravenous administration, in random order, of either physiological saline, 1 g aspirin, or 20 mg.kg-1 doxapram. Cardiac output (Q) was kept constant, to avoid passive Q dependent changes in Ppa. A progressive decrease in FIO2 from 100% to 12% was associated with an average increase in Ppa from 19 to 38 mm Hg (p < 0.001). When FIO2 was further decreased to 8%, Ppa decreased to 32 mm Hg (p < 0.01). This stimulus-response curve was unaffected by saline, but displaced in a non-PO2-dependent manner to higher Ppa by doxapram and by aspirin. The pulmonary vascular response to inspiratory hypoxia in intact anaesthetised piglets is biphasic, with a maximum at an FIO2 of 12%. Neither aspirin nor doxapram affect the shape of this stimulus-response curve, and in particular do not prevent low FIO2 associated inhibition of hypoxic pulmonary vasoconstriction.


Reperfusion arrhythmias after chronic regional denervation of the ischaemic myocardium in pigs. The aim was to assess the effects of chronic regional denervation of the ischaemic myocardium on reperfusion arrhythmias in a model with sparse coronary collateral circulation. Baseline ventricular refractoriness and epicardial activation times were measured together with reperfusion arrhythmias after 15 min (I-15') or 30 min (I-30') of left anterior descending coronary artery occlusion in 38 barbiturate anaesthetised open chest pigs. Twenty pigs (11 in I-15' and nine in I-30') had a chronic (two week) denervation of the left anteroseptal region, whereas 18 pigs (10 in I-15' and eight in I-30') were sham operated (non-denervated) controls. Denervation was induced by pericoronary application of phenol and verified by absence of adrenergic histofluorescence. As compared with controls, denervated pigs showed: (1) longer activation times: 20.3 (SD 5.2) ms v 16.5 (4.6) ms, p < 0.001; (2) slightly longer refractory periods: 348(28) ms v 334(27) ms; (3) a tendency to lower postreperfusion ectopic activity: ectopic beats divided by time free of ventricular tachycardia: 0.13(0.19) v 0.34(0.40) in I-15', and 0.21(0.24) v 0.39(0.44) in I-30'; (4) slower ventricular tachycardia in I-30': 140(29) beats.min-1 v 185(29) beats.min-1, p < 0.009; and (5) comparable incidence of postreperfusion ventricular fibrillation: 4/11 pigs v 2/10 in I-15', and 5/9 v 4/8 in I-30'. Selective chronic denervation of the ischaemic myocardium was unable to protect against malignant reperfusion arrhythmias in hearts with human-like coronary collaterals. This was confirmed at two ischaemic periods known to produce progressive catecholamine accumulation and increased adrenoceptor density in the ischaemic myocardium.


Intracoronary administration of saralasin: effects on cardiac arrhythmias induced by ischaemia and reperfusion in the anaesthetised dog. The aim was to study (1) the effects of intracoronary saralasin, an angiotensin II receptor antagonist, on ischaemia induced and reperfusion induced regional cardiac noradrenaline release and ventricular arrhythmias; and (2) the implication of angiotensin II in coronary constriction during myocardial ischaemia. Eighteen adult mongrel dogs, weight 22.6(SD 1.1) kg, anaesthetised with sodium pentobarbitone, were used for the study. The left anterior descending coronary artery was ligated for 60 min and then reperfused for 30 min. Saralasin (60 micrograms.kg-1, n = 9) or its vehicle (Ringer lactate, n = 9) was injected into the artery at the beginning of the occlusion period. Two epicardial veins, one running parallel to the left anterior descending coronary artery and the other parallel to the circumflex coronary artery, were cannulated for the measurement of their respective blood flows and of noradrenaline, lactate, and creatine kinase release. Saralasin decreased the incidence of ventricular fibrillation during coronary occlusion (from 44% in the vehicle treated group to 0% in the saralasin treated group, p = 0.0412). This effect was accompanied by significant vasodilatation in both epicardial veins during myocardial ischaemia. Neither the increases in noradrenaline, lactate, and creatine kinase release nor the incidence and duration of the ventricular arrhythmias following reperfusion were modified by the administration of saralasin. Intracoronary saralasin in the early phase of myocardial ischaemia increases the epicardial venous blood flow significantly, suggesting that angiotensin II is implicated in coronary constriction during ischaemia. This haemodynamic effect is accompanied by a significant decrease in the incidence of ventricular fibrillation. However, the renin-angiotensin system does not appear to be implicated in the reperfusion induced noradrenaline release nor in the incidence of the ventricular arrhythmias.


An unsaturated fat diet prevents the increased angiotensin II vascular responses in renal artery stenosis. The aim was to characterise angiotensin II constrictor responses in two kidney, one clip (2K1C) renal hypertensive rats fed a diet with a high unsaturated fatty acid content. Two diets with the same total fat (37% by energy; 17% by weight) but different unsaturated fat contents were fed to rats for a three month period. Thirty four Sprague Dawley rats were used per diet group. After one month on the diets, a group of 19 rats in each diet group was operated upon to induce 2K1C hypertension. A separate group of 15 rats within each diet group received sham operations. Systolic blood pressure was measured weekly from prior to surgery to the end of the three month feeding period. At three months, angiotensin II constrictor responses were evaluated in the isolated kidney vascular preparation and in intact anaesthetised rats fed the different diets. Phenylephrine constrictor responses were also evaluated in intact anaesthetised rats in order to exclude structural vascular changes accounting for differences in angiotensin II constrictor responses. The diet high in unsaturated fats prevented the development of hypertension in 2K1C rats [systolic pressure 134(7) mm Hg at eight weeks] compared to their own preoperative blood pressures [124(3) mm Hg], and to the 2K1C rats fed the control diet [163(7) mm Hg at eight weeks]. The diet high in unsaturated fats did not alter blood pressures in sham operated rats. In isolated perfused kidneys and in anaesthetised 2K1C rats fed the control diet, angiotensin II caused a greater vascular response compared to the sham operated groups. The unsaturated fat diet prevented this effect. No differences were found in blood pressure responses to phenylephrine. These data suggest that the antihypertensive effect of a high unsaturated fat diet may in part be due to a depressed responsiveness of vascular smooth muscle to endogenous angiotensin II. The effect is likely to be due to modulation of angiotensin II vascular responses by local vascular changes that cannot be accounted for by structural vascular differences.


Mechanical restitution of isolated human ventricular myocardium subjected to in vivo pressure and volume overload. The aim was to make a comparison of the mechanical and electrical refractory properties of isolated strips of human ventricular myocardium obtained from patients with either left ventricular pressure overload, volume overload, or normal left ventricular function. Strips of ventricular myocardium were obtained at the time of cardiac surgery from 17 patients with aortic stenosis, representing pressure overload, 14 patients with aortic regurgitation, representing volume overload, and nine patients with mitral stenosis, representing normal left ventricular function. Muscle strips were mounted isometrically in a tissue bath, superfused with physiological saline at 37 degrees C, and stimulated at 1 Hz. Mechanical restitution curves were constructed from the isometric twitch tension obtained from extrastimuli during a special stimulus protocol. Transmembrane action potentials were recorded using glass microelectrodes and restitution of the upstroke velocity of action potentials studied in the presence of high external potassium concentration. The aortic stenosis group was older and had higher left ventricular systolic pressures and thicker left ventricular walls than the other groups. Electrocardiographic evidence of left ventricular hypertrophy was present in both the aortic stenosis and aortic regurgitation groups. Peak tension, time to peak tension, and the maximum rates of rise and fall of tension were not significantly different between groups. The time constant of the initial rapid recovery phase of mechanical restitution (tau 1) was prolonged in the aortic stenosis group, at 603(SEM 80) ms v 367(53) ms in the aortic regurgitation group (p < 0.005), and 259(70) ms in the mitral stenosis group (p < 0.005). There was a positive correlation between tau 1 and left ventricular wall thickness (p < 0.05). Neither "normal" nor "slow" (in the presence of raised external potassium) transmembrane action potentials differed in the groups studied. The mean time constant of recovery of "slow" action potential dV/dtmax was slower in the aortic stenosis group, but this difference was not significant. These data are consistent with the hypothesis that the rate of recovery of calcium release from the sarcoplasmic reticulum is slowed in myocardial hypertrophy due to pressure overload in man and provides a possible explanation of the occurrence of mechanical alternans in such patients.


Ischaemic preconditioning limits infarct size in the rat heart. One of the mechanisms by which ischaemic preconditioning is thought to protect against later prolonged ischaemia is via a reduction in ATP utilisation during ischaemia. The ATP "wastage" that occurs during ischaemia is thought to be due to mitochondrial ATPase activity, which may be prevented in ischaemic preconditioning by the binding of a specific inhibitor protein. As the rat is known to have less inhibitor protein than other species, this study was designed to determine whether the rat heart could be ischaemically preconditioned. Rats were anaesthetised with pentobarbitone, the chest opened and the hearts ischaemically preconditioned with a 5 min occlusion of the left main coronary artery followed by 10 min reperfusion. The hearts were then subjected to a 45 min occlusion followed by 3 h reperfusion. Control hearts were treated identically but without ischaemic preconditioning. Infarct size was measured using triphenyl tetrazolium and expressed as a percentage of the region at risk, measured with fluorescent particles. Infarct size as a percent of the risk area in the ischaemically preconditioned group (n = 8) was 31.4(SEM 6.1)%, versus 61.0(4.8)% in control hearts (n = 8) (p < 0.005). These results show that rat hearts can be ischaemically preconditioned and suggest that the protective mechanism involved in this phenomenon is not mediated through the endogenous inhibition of mitochondrial ATPase. An overall reduction in mitochondrial ATP "wastage" may not be the sole mechanism in the protection seen in ischaemic preconditioning.


Effect of left ventricular systolic pressure increase on ventricular arrhythmogenicity in old canine myocardial infarction. The aim was to examine the effect of an increase in left ventricular systolic pressure (LVSP) on ventricular arrhythmogenicity in old canine myocardial infarction. Fourteen mongrel dogs of either sex weighing 11 to 15 kg were used. Studies were performed 28 d after creation of myocardial infarction by ligation of the anterior descending coronary artery. Electrical induction of ventricular arrhythmia and determinations of effective refractory period (ERP) and local intraventricular conduction delay (LIVCD) were performed using the extrastimulus technique with a cycle length of 300 ms in the normal and infarcted zones of the left ventricle. Heterogeneity of ERP (delta ERP) was determined as a difference between the longest and shortest ERP values in each site. LVSP was raised by constriction of the ascending aorta in a stepwise fashion (control, level A, level B). Incidence of electrically induced ventricular arrhythmia was increased from 28.6% at control level of LVSP [130.7(SEM 7.3) mm Hg] to 42.9% at level A [190.9(6.0) mm Hg] and to 64.3% (p < 0.05) at level B [243.3(4.0) mm Hg]. delta ERP and LIVCD were greater in the infarct zone than in the normal zone at each level of LVSP (p < 0.001). delta ERP in the infarct zone increased from 18.9(4.3) ms at control level of LVSP to 20.7(6.8) ms at level A, and to 27.1(8.1) ms at level B (p < 0.001). LIVCD in the infarct zone also increased from 22.9(6.2) ms at control level of LVSP to 26.8(4.9) ms at level A (p < 0.001), and to 36.1(6.0) ms at level B (p < 0.001). delta ERP and LIVCD in the normal zone were only slightly raised by increasing the LVSP. delta ERP and LIVCD in the infarct zone were closely correlated with incidence of electrically induced ventricular arrhythmia. Increasing the LVSP enhances ventricular arrhythmogenicity and pre-existing electrophysiologic abnormalities of the heart in the presence of old myocardial infarction. Thus a rise in LVSP from any cause in the old myocardial infarction can be a trigger of life threatening ventricular arrhythmias.


Histological and angiographic effects of a pulsed holmium:YAG laser in normal and atherosclerotic human coronary arteries and aorta. The aims were (1) To determine the histological and angiographic effects of holmium:YAG laser energy delivered through clinical multifibre laser catheters on fresh cadaveric coronary arteries; and (2) to relate the placement of optical fibres in the catheter to patterns of tissue ablation in cadaveric aorta. Eight fresh cadaveric hearts and segments of aorta were used. Hearts were mounted on a new pressure perfusion device. The laser catheter was delivered over a guidewire in the lumen until it met an area of resistance. The coronary artery lumen was perfused at approximately 100 mm Hg mean pressure. These arterial areas were identified on angiography, marked, and then exposed to laser energy in the range 600-3000 mJ.mm-2. Normal and atherosclerotic areas of fresh cadaveric aortic strips were exposed to increasing laser energies using either constant or increasing fluence. Coronary arteries were pressure perfused with formalin for 18-24 h at 100 mm Hg mean pressure, and aortic strips were immersed in 5% formalin. Light and scanning electron microscopy studies were carried out. There were no perforations or dissections by angiography in the fresh coronary arteries. One of 15 normal coronary artery segments and 10 of 16 of the pressure perfused, fixed, atherosclerotic coronary artery segments showed thermal changes associated with atherosclerotic plaque ablation. In aortic tissue, thermal effects extended 0 to 0.6 mm lateral to the ablated crater. Acoustic effects were seen only in the aortic strips after ablation at fluences > 1000 mJ.mm-2. The "dead spaces" around the optical fibres in the catheter resulted in significant amounts of coagulated tissue fragments remaining in the crater. Holmium:YAG laser energy delivered through multifibre catheters ablated atherosclerotic tissue in coronary arteries with minimal damage to the normal walls. The cadaveric coronary artery perfusion apparatus is useful for assessing catheter delivery and mobility and the effects of laser energy on the coaxially orientated normal and atherosclerotic coronary arterial wall.


Proliferative and functional stages of rat ameloblast differentiation as revealed by combined immunocytochemistry against enamel matrix proteins and bromodeoxyuridine. A double-staining immunocytochemical technique was used for the simultaneous detection, at the light- and electron-microscopical level, of proliferating bromodeoxyuridine (BrdU)-labelled cells and enamel protein (EP)-producing cells in the inner enamel epithelium (IEE) of rat tooth germ. BrdU-positive cells were found in the region of the IEE close to the cervical loop and never displayed EP-like immunoreactivity. BrdU-immunoreactivity was confined to the nucleus of replicating cells. In contrast, epithelial cells displaying EP-like immunoreactivity were found in the region of the forming dental cusp and were consistently BrdU-negative. EP-like immunoreactivity was detectable in the cytoplasmic compartments involved in the exocrine secretion pathway and in the extra-cellular matrix close to EP-immunoreactive cells. These data support the view that withdrawal from the cell cycle in the IEE is a temporal prerequisite for acquiring the functional competence of secreting EP. Moreover, cycling cells and secretory cells in the IEE constitute two separate compartments that are spatially defined, and that exhibit clear-cut staining patterns with respect to BrdU- and EP-immunoreactivity, respectively. We thus propose that BrdU-incorporation and EP-production may be used as specific markers of the differentiation of the IIE cells in studies of the possible role of growth factors, their receptors and oncoproteins in this tissue.


Colocalization of neuropeptide Y (NPY)-like and FMRFamide-like immunoreactivities in the brain of the Atlantic salmon (Salmo salar). The colocalization of the peptides neuropeptide Y (NPY) and Phe-Met-Arg-Phe-NH2 (FMRFamide) in the brain of the Atlantic salmon was investigated with double immunofluorescence labeling and peroxidase-antiperoxidase immunocytochemical techniques. Colocalization of NPY-like and FMRF amide-like immunoreactivities was observed in neuronal cell bodies and fibers in four brain regions: in the lateral and commissural nuclei of the area ventralis telencephali, in the nucleus ventromedialis thalami, in the laminar nucleus of the mesencephalic tegmentum, and in a group of small neurons situated among the large catecholaminergic neurons in the isthmal region of the brainstem. All cell bodies in these nuclei were immunoreactive to both NPY and FMRF. We consistently observed larger numbers of FMRF-immunoreactive than NPY-immunoreactive fibers. In the nucleus ventromedialis thalami NPY- and FMRFamide-like immunoreactivities were colocalized in cerebrospinal fluid (CSF)-contacting neurons. NPY-immunoreactive, but not FMRF-immunoreactive, neurons were found in the stratum periventriculare of the optic tectum, and at the ventral border of the nucleus habenularis (adjacent to the nucleus dorsolateralis thalami). Neurons belonging to the nucleus of the nervus terminalis were FMRF-immunoreactive but not NPY-immunoreactive. The differential labeling indicates, as do our cross-absorption experiments, that the NPY and FMRFamide antisera recognize different epitopes. Thus, it is probable that NPY-like and FMRF amide-like substances occur in the same neurons in some brain regions.


FMRFamide-like immunoreactivity in the brain of the Pacific hagfish, Eptatretus stouti (Myxinoidea). The distribution of FMRFamide-like immunoreactivity was investigated in the brain of a myxinoid, the Pacific hagfish, Eptatretus stouti, by means of immunocytochemistry. In the forebrain, labelled cell bodies occurred in the infundibular nucleus of the hypothalamus and some closely adjacent nuclei. Labelled fibers formed a diffuse network in the forebrain, but there was no evidence for the presence of intracerebral ganglionic cells of the terminal nerve or a central projection of the terminal nerve. In the hindbrain, a group of labelled cells was found in the trigeminal sensory nucleus. A distinct terminal arborization occurred in the ventrally adjacent nucleus A of Kusunoki and around the nuclei of the branchial motor column. These findings suggest that FMRFamide may play a role in the central control of branchiomotor activity.


Extra-Golgi pathway of an acrosomal antigen during spermiogenesis in the rat. A monoclonal antibody (MC41) was produced that specifically recognizes a sperm acrosomal antigen of approximately 165,000 dalton in the rat. Rat testis was examined using a pre-embedding immunoperoxidase technique to reveal the pathway of the MC41 antigen to the acrosome during spermiogenesis. The MC41 immunoreaction appeared in several organelles of spermatids in a stage-specific manner: (1) in the endoplasmic reticulum (ER) throughout spermiogenesis, (2) in the outer acrosomal membrane from steps 9 to 19, (3) as a weak immunoreaction in the vesicular structures in the acrosomal matrix from steps 11 to 17, and (4) as a strong immunoreaction in the acrosomal matrix especially at the terminal step of spermiogenesis (step 19). However, no immunoreaction was observed in the Golgi region throughout spermiogenesis. These results suggest that the pathway of the MC41 antigen leads firstly from the ER to the outer acrosomal membrane and secondly to the acrosomal matrix. This pathway does not involve the Golgi apparatus and is referred to as the "extra-Golgi pathway".


Characterization of the antigen recognized by a monoclonal antibody MN9: unique transport pathway to the equatorial segment of sperm head during spermiogenesis. MN9, a monoclonal antibody raised against mouse spermatozoa, specifically recognizes the equatorial segment of sperm head in several mammalian species, including humans. Colloidal gold-immuno-electron microscopy of mouse spermatozoa has shown that the antigen is localized in the space between the outer and inner acrosome membranes and on the acrosome membranes at the equatorial segment. Immunoblotting after electrophoresis of spermatozoa from the cauda epididymidis has identified two immunoreactive bands: 38 kDa and 48 kDa in mouse, and 48 kDa in rat. During spermiogenesis in rat, this antigen is transported to the equatorial segment via a unique pathway, first appearing in some cisternae of the endoplasmic reticulum and in the Golgi apparatus of spermatids at around step 3. The antigen can further be found on the vesicles at the trans-side of the Golgi apparatus, in the matrix of the head cap, and on the head cap membrane in step-4 to step-7 spermatids. The antigen appears to be concentrated at the equatorial segment during late spermiogenesis. Neither the (pro-)acrosomic granule nor the surrounding membrane are required in this pathway. This pathway can be termed the 'Golgi-head cap tract'.


Distribution of intraventricularly injected horseradish peroxidase in cerebrospinal fluid compartments of the rat spinal cord. The circulation of the cerebrospinal fluid along the central canal and its access to the parenchyma of the spinal cord of the rat have been analyzed by injection of horseradish peroxidase (HRP) into the lateral ventricle. Peroxidase was found throughout the central canal 13 min after injection, suggesting a rapid circulation of cerebrospinal fluid along the central canal of the rat spinal cord. It was cleared from the central canal within 2 h, in contrast with the situation in the brain tissue, where it remained in the periventricular areas for 4 h. In the central canal, HRP bound to Reissner's fiber and the luminal surface of the ependymal cells; it penetrated through the intercellular space of the ependymal lining, reached the subependymal neuropil, the basement membrane of local capillaries, and appeared in the lumen of endothelial pinocytotic vesicles. Furthermore, it accumulated in the labyrinths of the basement membrane contacting the basolateral aspect of the ependymal cells. In ependymocytes, HRP was found in single pinocytotic vesicles. The blood vessels supplying the spinal cord were classified into two types. Type-A vessels penetrated the spinal cord laterally and dorsally and displayed the tracer along their external wall as far as the gray matter. Type-B vessels intruded into the spinal cord from the medial ventral sulcus and occupied the anterior commissure of the gray matter, approaching the central canal. They represented the only vessels marked by HRP along their course through the gray matter. HRP spread from the wall of type-B vessels, labeling the labyrinths, the intercellular space of the ependymal lining, and the lumen of the central canal. This suggests a communication between the central canal and the outer cerebrospinal fluid space, at the level of the medial ventral sulcus, via the intercellular spaces, the perivascular basement membrane and its labyrinthine extensions.


Ca2+-ATPase in mucous and oxyntico-peptic cells of the fowl proventriculus. Calcium adenosine triphosphatase (Ca(2+)-ATPase) was localized by means of histo-and ultracytochemistry in the secretory cells of the proventriculus of the domestic fowl. The mucous cells exhibited plasmalemmal-associated enzyme activity on the external aspect of the basolateral cell membrane. Intracellularly, the luminal aspect of Golgi-membranes and of secretory vesicle membranes reacted positively for Ca(2+)-ATPase activity, as did the apical cytosol and the matrix of lysosomes. Oxyntico-peptic cells were characterized by apical and apico-lateral plasmalemmal activity and by an organelle-associated distributional pattern similar to that in the mucous cells. In addition, Ca(2+)-ATPase was associated either with the matrix of mitochondria or with tubuli of the rough-surfaced endoplasmic reticulum. The results are discussed with respect to messenger and effector functions of calcium in the process of proventricular mucus secretion. In addition, Ca(2+)-ATPase distributional patterns in the oxyntico-peptic cell are related to the unique structure and function of these cells.