Case report: top hearing performances of a postlingually deaf cochlear implant user. On the occasion of the Cochlear Implant Symposium in Geneva in October 1991, top hearing results attained by a young postlingually deaf woman with cochlear implant systems were presented in video recordings. These data are centered on demanding hearing performances in test situations and in a telephone conversation. For various reasons, two reimplantations were necessary in this deaf patient. Initially, she was provided with a single-channel extra-cochlear electrode of the Vienna type, which she found to improve her lipreading substantially, and she attained an unexpectedly good understanding of speech on a purely auditory basis. Today, this postlingually deaf women uses a multichannel intracochlear electrode of the Nucleus type. The excellent results with the first extracochlear system are clearly surpassed with the intracochlear system. Not least because of her above-average speech competence, the cochlear implant user attains a high degree of open speech understanding. Her verbal hearing efficiency is comparable to that of a person with mild to moderately severe hearing loss.


Autograft ossiculoplasty in cholesteatoma. Although using autogenous ossicles in reconstruction offers stable hearing results with good tendency for healing and minimal extrusion, their use in cholesteatomatous ears has been criticized for the possibility of progressive osteitis, bone resorption and cholesteatoma recurrence. In the present study we have been investigating a way which affords safe re-implantation of such ossicles. Treatment by burring followed by autoclaving seems to offer an implant that is safe both bacteriologically and pathologically. We have found no evidence that cholesteatoma could develop from such treated ossicles.


Ear polyps in posterior superior retraction pockets, herodion. Histopathological and pathogenetic aspects. Histopathological characteristics of 20 ear herodion polyps with a certain localisation and a well-known underlying pathological process were studied in order to elucidate the pathogenesis of ear mucosal polyp formation. Only 12 of the polyps were covered with epithelium; either a squamous keratinized epithelium or a cylindrical epithelium. Three polyps were covered with cylindrical and squamous keratinized epithelium. Incipient gland formation was seen and glands were only found in 35% of the polyps. It seems possible that the polyp is a local newly formed process and may have the aim of catching, eliminating and digesting bacteria and dead cells.


An unusual case of Castleman's disease restricted to the neck. An unusual case of Castleman's disease (CD) restricted to the left cervical area is reported. CD is rarely confined to the cervical area; when it occurs, it is usually of the hyaline-vascular subtype and small in size. This case was atypical due to its histology (plasma-cell variant), big size (15 x 11 x 6 cm) and the absence of general symptoms. In spite of surgical excision, the disease recurred 11 months later. However, subsequent surgery followed by chemotherapy resulted in a long-lasting control of the disease.


Candida and stapedial otosclerosis: histopathological findings. The stapes of 6 patients with stapedial otosclerosis was found to contain fungus hyphae (Candida) in the sectioned specimens. The footplate of all cases and the head of the stapes in 2 of the cases revealed single or multiple erosion cavities containing numerous thin branching PAS-positive fungus hyphae with swollen terminal endings and scanty blastospores. Osteoclasts were not observed; occasional osteoblasts, blue mantles and otosclerotic foci were seen. Four patients had been treated for several years with antibiotics and corticosteroids for recurrent serous otitis media and 1 patient had had frequent catheterization of the eustachian tube. It may be suggested that the Candida infection was a secondary event induced by a general and/or local immunodepressed condition.


[The value of polypeptide analysis (beta-2-microglobulin, microalbuminuria, beta-thromboglobulin) in the diagnosis of diabetic nephropathies]. The value of polypeptide analyses in the diagnoses of diabetic nephropathy. Early diagnostic signs are rapidly gaining importance in the prevention and care of diabetic complications. The aim of this paper was to review the clinical significance of measurements of the serum and urine levels of beta-2-microglobulin, microalbuminuria and the plasma and urine levels of beta-thromboglobulin. We would like to emphasize their possible role in monitoring and prediction of the chronic sequelae of diabetes mellitus.


[Study of the origin of hyperglycemia in acute myocardial infarct]. In order to clarify the origin of hyperglycaemia, blood glucose, glycated haemoglobin (GHb) and protein-corrected serum fructosamine (SFA) values were simultaneously determined at admission of 65 patients with acute myocardial infarction while oral glucose tolerance test was performed later at discharge. In 29 patients no alterations in carbohydrate metabolism were found (blood glucose: 5.2 +/- 0.1 mmol/l, GHb: 4.4 +/- 0.1%, SFA: 2.20 +/- 0.08 mmol/l) while in 9 patients diabetes was already recorded in the medical history (blood glucose: 11.5 +/- 1.1 mmol/l, GHb: 7.9 +/- 0.9%, SFA: 3.36 +/- 0.31 mmol/l, p < 0.001). Undiagnosed diabetes was documented in 8 patients (blood glucose: 11.8 +/- 1.3 mmol/l, GHb: 7.3 +/- 0.6%, SFA: 3.51 +/- 0.24 mmol/l) while stress-hyperglycaemia was found in 19 patients (blood glucose: 8.4 +/- 0.3 mmol/l, GHb: 4.5 +/- 0.1%, SFA: 2.55 +/- 0.17 mmol/l). Undiagnosed diabetes could be recorded in one seventh while stress-hyperglycaemia could be found in one third of non-diabetic patients with acute myocardial infarction. Due to overlapping values SFA is not suitable to distinguish between stress-hyperglycaemia and undiagnosed diabetes in patients with acute myocardial infarction.


[Advantages and limitations of single-channel urodynamics in childhood]. The simultaneous recording of urodynamic parameters and x-ray imaging of the lower urinary tract is the ideal technique for a complex investigation of the lower urinary tract morphology and function. The urodynamic and micturating cystourethrography findings were reviewed in 57 children. The causes of the examinations were recurrent urinary tract infection, voiding dysfunction and urinary tract dilatation by ultrasound. 53/57 patients had a clear cystomanometry results. 4 did not cooperate. 15/53 had unstable bladder. 34/57 had vesico-ureteric reflux. Unilateral reflux was more frequently noted in children with an unstable bladder. In cases of a stable bladder, bilateral reflux occurred more frequently. The ureteric reflux in children with unstable bladder should resolve with therapy to decrease bladder activity. Urodynamics is complementary rather than competitive with radiologic investigations. It is necessary to make micturating cystourethrography with cystomanometry.


[Spontaneous esophageal perforation related to fungal esophagitis]. The authors give account of spontaneous esophageal perforation developed on the basis of fungal oesophagitis. The lesion of the lower third of the esophagus classified as grade 4. on Kodsi classification displayed the same picture as an advanced esophageal cancer. They review signs, symptoms and varieties in macroscopic appearance of esophageal candidiasis. They warn that in case of a spontaneous perforation of "malignant" esophageal tumor with no preceding signs the rare condition of fungal esophagitis must certainly be considered.


[Etiology, symptomatology, diagnosis, differential diagnosis and management of Crohn disease]. The non specific, chronic, inflammatory, granulomatous Crohn's disease is not common in our country. Despite wide clinical and experimental experiences, its etiology hasn't been cleared yet. Its symptoms are especially various. The diagnosis--particularly in early stages--despite the clinical feature and modern diagnostic methods, is difficult. Only histology can give exact diagnosis. However Crohn's disease often can be diagnosed only on the basis of clinical symptoms, later appearing complications featuring this disease--particularly fistula--and indirect histological changes that can be seen in biopsy. Differential diagnosis--particularly in early stages--is also difficult, as the symptoms of Crohn's disease may be similar to symptoms of any other abdominal diseases. The therapy of Crohn's disease is mainly medical, even in some of those cases, when the occurring complications don't threaten the patient's life. Remission doesn't mean total recovery. Even by supporting treatment the disease may relapse at any time. Surgical treatment in indicated only in those cases, when complication occur threatening the patient's life, when active medical treatment is insufficient, or despite medical treatment progression can be observed.


[Circadian rhythm of blood pressure in hypertension treated with enalapril and other drugs]. Twenty-four-hour "ambulatory blood pressure monitoring" (ABPM) was performed during the day at every 30 min and during the night at every 60 min in 38 persons admitted to the hospital. The subjects were divided into four groups: Group 1. healthy subjects (11); Group 2. essential hypertensive patients (7) before and during enalapril treatment; Group 3. patients with essential hypertension (10) treated with different antihypertensive drugs and Group 4. renal patients treated as in Group 3. Normal circadian rhythm was found in the healthy subjects and in the patients with essential hypertension, but no rhythm could be demonstrated in the renal patients. The high blood pressure decreased in response to enalapril in 7 patients without any decrease in the circadian rhythm. It was concluded that antihypertensive therapy does not abolish the circadian rhythm if there is any--and does not restore if it is lacking. The chances of the diagnostic use of circadian blood pressure rhythm are not impaired by the antihypertensive treatment.


[Primary hemostasis studies in Conn syndrome]. The various components of haemostasis seems to be affected by the high cortisol level in Cushing's disease. Increase in coagulation factor levels, decreased fibrinolysis, high von Willebrand factor plasmatic levels along with easy bruising due to vascular damage have been described. In this report a similar but less accentuated elevation of von Willebrand factor levels are documented in aldosterone producing adrenocortical adenoma, and in the same time enhanced platelet activation was also found. The primary haemostatic alterations correlated well with aldosterone levels and subsided significantly after the removal of the ademonas. Further studies seem to be desirable to analyse and elucidate haemostatic functions in Conn's syndrome.


[Refertilization after sterilization using surgical micromethods in gynecology]. The authors aquaint the results of refertilization following sterilization in connection eight cases. Four of their patients delivered mature babies in term. The microsurgical methods following different forms of sterilization are described in details. Refertilization can be a real possibility for women who had previously undergone sterilization and would like to be pregnant again.


[Selective vitamin B12 absorption disorder (Imerslund-Gräsbeck syndrome)]. The authors present a case of Imerslund-Gräsbeck syndrome, i. e. a familial megaloblastic anemia with proteinuria. The disease is due to congenital, selective malabsorption of vitamin B12. The subnormal absorption of vitamin B12 is not altered by orally given intrinsic factor, but parenteral vitamin B12 therapy results in complete recovery. Approximately 150 cases have been described in literature, the authors' case is the first in Hungary.


[Diagnosis, classification and indications for surgical treatment of pelvic ring fractures]. In cases of high-energy trauma, it is well known that there is a high incidence of pelvic fractures. The mechanism of injury, inspection and physical examination of the victim at the accident site direct attention to a pelvic fracture. In most cases, the first radiological examination (A.P. X-ray of the pelvis, oblique view of the obturator and oblique view of the ilium) shows the extent of the bony lesion. The diagnosis and therapy of lesions of the urinary tract, of intra-abdominal organs and blood vessels are vitally important. For the definitive operation of unstable pelvic ring fractures, additional diagnostic means, i.e., CT scans to distinguish posterior instability, can be necessary. Osteosynthesis can only be successful in the pelvis if one has a biochmechanical understanding of the physiological flux of force from the neck of the femur via the acetabular fossa to the sacroiliac joint. The sacroiliac ligaments have a particularly important support function. For assessing stability and classifying the traumatic patterns, it is helpful to use Pennal's classification, which takes the direction of the action of force into account. Three basic forms can be distinguished: anteroposterior compression, lateral compression and vertical avulsion. Depending on the extent of the traumatic pattern, one can distinguish three subtypes: type 1 is treated conservatively while types 2 and 3 require surgical treatment. The biochmechanics, traumatic patterns, diagnostics and treatment techniques applied are described clearly and with good illustrations.


[Stabilizing the pelvic ring with the external fixator. Biomechanical studies and clinical experiences]. Experimental studies were performed on anatomic pelvis specimens. In different series of experiments the positioning of the screws and the assembly of the external fixator were changed. We tried fixing the external fixator to the screws at varying distances from the body surface. For stabilisation of the fractured pelvic girdle a self-constructed "bow fixator", fixed to supra-acetabular screws with proximal compression and distal traction showed the best results. Homogeneous distribution of the pressure could be achieved on the unstable dorsal pelvic ring structures. In clinical routine we used the triangular external fixator, which in the experimental situation yielded results close to those of the bow fixator. External fixation of the pelvic girdle has been performed 128 times since 1977, in January 1991 a prospective study was started. For Tile type B injuries the external fixator itself represents an effective, minimally invasive system, but type C fractures often require an additional internal fixation of the dorsal lesion.


[Standardized osteosynthesis techniques for the pelvic ring. Analysis of a patient sample and surgical technique]. A total of 1566 patients with fractures of the pelvis were treated at the Department of Traumatology at the Hannover Medical School between 1972 and 1990. Of these, 1350 patients had fractures of the pelvic ring, 216 isolated acetabulum fractures, and 398 combinations of pelvic ring fractures and acetabular involvement. Of these patients, 718 were admitted with severe polytrauma. For 1254 patients complete files were available for clinical and radiological evaluation of fracture distribution, classification (Tile and anatomical location) and concomitant injuries. A significant increase in the severity of trauma, the severity of the pelvic fractures and the rate of internal stabilization, especially of the posterior pelvic ring, was observed during the observation period. The overall mortality after pelvic fracture was 18.1%. This mortality was correlated to the Hannover Polytrauma Score (PTS) and the associated extrapelvic blunt trauma. Internal fixation of pelvic fractures was performed in 195 patients. Our experience led to standardized procedures for the different fracture locations. In fractures type Tile B, an anterior procedure led in all cases to anatomic or near anatomic healing. In unstable pelvic ring fractures (Tile C), external fixation led to a significantly higher rate of posterior dislocations (over 1 cm) than did internal fixation. In these situations a combined posterior and anterior internal fixation procedure improved the result compared to posterior internal stabilizations alone. As a result, internal stabilization using a standardized technique for every fracture location is recommended for all unstable pelvic ring fractures.


[Primary management of pelvic injuries]. High energy fractures of the pelvis are often associated with genitourinary, neurological, vascular, intestinal, and other skeletal injuries. The pelvic fracture therefore reflects only some of the destructive energy sustained by the patient and is a marker for the associated soft tissue injuries. In these complex pelvic injuries assessment, stabilization, and definitive treatment are complicated. The mortality of complex pelvic injuries is high. Uncontrolled bleeding and septic complications are the main causes of death. The presence of the associated injuries necessitates thorough evaluation in every case. The goals of treatment are prevention of early death from hemorrhage, early detection and treatment of all concomitant injuries, and restoration of the patient to the preinjury level of function. At the scene of the accident, problems affecting the airway, breathing, and circulation should be dealt with first. For prehospital immobilization and transportation of the patient a beanbag should be used. With the aim of improving primary hospital treatment of patients with complex pelvic injuries, a trauma algorithm is presented. This provides for decisive therapeutic steps after brief clinical, radiologic and ultrasonographical assessments. The major questions in the flow chart take the pelvic ring and hemodynamic instability into account. Immediate laparotomy, surgical control of hemorrhage, and open reduction and internal fixation of an unstable pelvic ring are the most important requirements for successful treatment. From 1972 to 1990 the clinical course and outcome of 132 patients with complex pelvic injuries were reviewed. The overall mortality was 34.8%. As the changes in the treatment protocol were implemented mortality decreased from 66.7% (1972-1978) to 18.7% (1985-1990).


[Pelvic clamps for controlling shock in posterior pelvic ring injuries. Application, biomechanical aspects and initial clinical results]. The antishock pelvic clamp provides direct reduction and compression of unstable posterior pelvic ring disruptions. This is effective in preventing excessive blood loss, which is common in these fractures. Comparable to a carpenter's C-clamp, this device is applied in less than 10 min and exerts transverse compression directly over the iliosacral region, reducing the displaced sacral fractures or SI joint diastasis. Early reduction closes the bleeding surfaces and restores the intrapelvic space, providing for earlier tamponade, further decreasing blood loss. The clamp does not interfere with a possible subsequent laparotomy or necessary diagnostic procedures. On 10 cadaveric pelvic specimens the bone yield under compression with the pelvic clamp ranged from 135 N to 685 N relative to the mechanical quality of the bone. This is sufficient to stabilize the posterior ring during further manipulation of the patient in the early phase. Details of the application technique and our clinical experience with the pelvic clamp in the first 17 patients are discussed.


[The problem of the sacrum fracture. Clinical analysis of 377 cases]. Sacral fractures are rare injuries that are often neglected because of the general severity of the patient's injuries. They are typical injuries in patients with polytraumata. A "hidden" injury, they are often diagnosed late or are even missed. In a well-documented consecutive series of 1,350 patients with pelvic fractures treated in the trauma department of the Hannover Medical School between 1972 and 1991, a total of 377 sacrum fractures were evaluated in a retrospective study. The cause of the accident, mechanism of injury, concomitant injuries, diagnostic procedures, classification of the pelvic injury (TILE), as well as the classification of the sacrum injury (DENIS), treatment and outcome were analyzed in all cases. Observed complications with special attention to injuries to the lumbosacral plexus were correlated with the classification of the sacrum and pelvis, as well as with a detailed analysis of the fracture pattern and fracture characteristics. In 89.4% at least one additional body region was injured in these patients. PTS (Hannover Polytrauma Score) groups III and IV included 42.5% of the patients. With an improved diagnostic protocol (radiological a.p. views, oblique views and CT scan), the observed rate of sacrum fractures was 33%. Neurological deficits occurred in 15.1% of the patients. In contrast to the literature, the rate of neurological deficits was related more to the degree of pelvic instability (TILE) than to the specific fracture pattern in the sacrum. In stable injuries (TILE A) neurological deficits were only seen in exceptions. In type B injuries the maximum rate was 10%, whereas in unstable fractures (TILE C) the rate of neurological deficits was 32.6% in transalar fractures (DENIS zone I), 42.9% in transforaminal fractures (DENIS zone II), and 63.6% in central fracture types (DENIS zone III). Additional risk indicators for neurological impairment are avulsion fractures of the sacrum, comminuted and bilateral fracture lines. The fracture classification should thus be modified. Our own experience with operative therapy for sacral fractures (open revision of the sacral plexus together with internal stabilization of the fracture) is still limited, but based on the experience presented, further development of the treatment protocol for sacrum fractures should be considered.


[Comparative biomechanical studies of internal stabilization of trans-foraminal sacrum fractures]. A new method of internal stabilization of transforaminal sacrum fractures in unstable pelvic ring fractures was developed by modification of standard AO small-fragment implants. The rationale of this type of stabilization is the use of an unilateral dorsal approach and avoidance of transfixation of the uninvolved SI joints. In a comparative biomechanical study on 8 human cadaver pelvises two types of the new type of stabilization were compared to stabilization with Harrington sacral bars and transiliosacral screw fixation. The fracture model represented a Tile C1 type injury (symphysis disruption and transforaminal sacral osteotomy) on a complete pelvic ring. The anterior stabilization was performed with a 4-hole AO 4.5 mm DC plate in all cases. The load simulation used a one-leg standing model in an upright position with abductor muscle simulation. The pelvises were loaded in 4 load stages of 50%, 80%, 100% and 130% body weight. In each load stage 4 load-unload cycles were completed. With a three-dimensional measurement system (Polhemus 3 Space Motion Tracker) translations an rotations in the fracture plane could be analyzed. Typical behavior in the load-displacement curve was seen in all implants, with settling during the first cycles and permanent displacement after exceeding a specific failure load. The failure load showed no significant differences between implants (99.6-113.6% body weight). The analyses of the persistent displacement, the elasticity and the direction of displacement and rotation showed a typical behavior in the implants, but no differences, which can be interpreted as a significant difference in the stability of the fixation methods. In an additional test the new fixation method showed no loosening in 10,000 cycle loading with 60% body weight. The new stabilization method showed biomechanical results comparable to clinically successful methods of stabilization in the chosen fracture model. Thus, clinical applications of this type of stabilization may be successful.


[Malgaigne pelvic ring injury in childhood]. Pelvic girdle injuries leading to anterior and posterior disruption are rarely seen in children. External fixation is useful to reduce and stabilize the pelvis in order to control massive blood loss due to severe venous bleeding. The anterior tension band element of the external fixator can successfully maintain reduction of the pelvic girdle. Dislocation or fracture dislocation of the sacroiliacal joint cannot be reduced with simple traction techniques. Leg length discrepancy is to be expected when the hemipelvis is displaced. Seven cases of this rare injury in children are presented together with the late outcome. Treatment modalities are discussed.


[Diagnosis, classification and surgical indications in acetabulum fractures]. Displaced acetabular fractures may lead to posttraumatic arthritis. Consequently, joint congruency must be restored by either conservative or operative measures. Standardized radiographs of the pelvis are prerequisites for the correct evaluation of the hip-joint. The a. p.-pelvis projection and the Judet views (obturator and iliac oblique) showing the whole pelvis are indispensable and demonstrate radiological landmarks typical of anatomical relationships and fracture characteristics. The two dimensional computertomogram is an adjunctive diagnostic measure and facilitates the evaluation of the hip joint itself. The 3DCT allows the imaging of old acetabular fractures and aids in the planning of reconstructive surgery. With the basic three projections of the hemipelvis, Letournel and Judet developed the acetabular fracture classification now accepted world-wide. Assuming the notion that the acetabulum is supported by two columns, five fracture types and five fracture type combinations are described according to involvement of the anterior or posterior columns respectively. The correct classification precedes the choice of surgical approach and is the basis for preoperative planning. The indications for surgery adhere to the principles of joint surgery. Conservative treatment may be considered only if the weight bearing joint surface of the acetabulum is congruent. Otherwise open reduction and internal fixation are indicated.


[Surgical approaches, choice of approach and surgical techniques for internal stabilization of acetabulum fractures]. The choice of surgical approach to fractures of the acetabulum is determined by the type of fracture. The most popular approaches are the Kocher-Langenbeck, the ilio-inguinal and the extended iliofemoral. The techniques of reduction and internal fixation using special instruments and implants are demonstrated.


[The Pelvic Professional Section of the German Society of Accident Surgery and the German Section of AO-International]. On the occasion of the 1990 Conference of the German Society for Accident Surgery (DGU) in Berlin, a working group "Pelvis" of the DGU and the AO International was established on the initiative of H. Tscherne. It is the objective of this working group to formulate guidelines for the diagnosis and treatment of pelvic girdle fractures, within the framework of a prospective multicentre study based on comparable results. In the annual report for 1991, a total of 460 pelvic fractures were documented. Classification shows that 9.5% belong to group A, 46.3% to group B, and 44.2% to group C. One hundred and eighty-two patients (39.6%) had an isolated pelvic injury, while 278 (60.4%) sustained multiple injuries. The average polytrauma score for all 460 subjects was 23.2 points. The surgical management was shown to depend on the severity of the fracture.


[The principles of the diagnosis of acute intestinal infections caused by opportunistic bacteria in children]. To specify criteria for the diagnosis of acute intestinal infections induced by opportunistic bacteria, the clinico-laboratory findings were compared in 3 groups of children: with acute intestinal infections induced by opportunistic bacteria (194 children); with shigellosis, salmonellosis and escherichiosis (260 children); with rotavirus gastroenteritis (133 children). It has been demonstrated that in the diagnosis of acute intestinal infections induced by opportunistic bacteria, one should be very careful in excluding the etiological role of pathogenic bacteria and viruses not only clinically but also with the aid of laboratory virological, bacteriological and serological methods; in considering changes in the quantitative content of the intestinal microflora to be seen over time. It is also necessary that the age and the premorbid condition of the patients examined may be taken into account.


[Clostridium difficile and diarrhea in infants in the first half-year of life]. In order to study a possible etiological relationship between Clostridium and diarrhea in children of the first half year of life and to characterize the colonization of the intestine with these bacteria, bacteriological investigations of feces were carried out in neonates and babies aged 1, 4 and 14 days and 1, 3 and 6 months. The development of the children and their health status were monitored under home conditions. It has been established that the colonization of the neonates' intestine with Clostridium including C. Difficile occurs within the early times (since the 4th day of life). Later the colonization with C. difficile becomes wavy in nature. Among 7 types of Clostridium isolated from the intestine of the children, C. difficile occurred most frequently (29.1%). The overwhelming majority of the strains of these bacteria produced toxin whose activity did no exceed 10(-1)-10(-2). The cytopathic effect was mostly demonstrable in 72 hours. No convincing evidence was obtained about the etiological importance of C. difficile in the development of diarrhea in the children placed under observation. It is likely that the latter one was due to the disturbance of intestinal biocenosis, that manifested by profound quantitative disorders (proliferation of the opportunistic aerobic flora, a dramatic reduction of the content of bifido- and lactic acid bacteria up to their complete absence). At the same time a great number of children carrying C. difficile attests to a potential development of specific diarrheas (under hospital conditions and during massive antibacterial therapy).


[Changes in the peripheral circulation of children with severe forms of acute intestinal infections]. Photoelectroplethysmography of the skin of the end phalanx of the right hand thumb was used in 100 children with grave forms of acute intestinal infections and in 31 healthy babies to study changes in peripheral circulation. The patients demonstrated the lowering of the skin blood content, in proportion to the degree of dehydration, as well as an increase of postcapillary resistance to the blood flow in the skin and subcutaneous fat, seen not only in the acute disease period but also in the stage of early convalescence.


[The pathogenetic significance of disorders in macrophage function in viral hepatitis B and delta in children]. Overall 180 children aged 3 months to 12 years with acute and chronic hepatitis B and delta were examined for macrophagal function. Chemotaxis, saturation with esterase, the content of nuclear RNA were estimated, antigens of HB virus in these cells were identified as well. The data obtained attest to the correlation between the degree of macrophagal function disorders and the gravity of acute virus hepatitis. The chronic disease is characterized by stable depression of mononuclear cells with a tendency toward deeper depression of their function in patients with virus hepatitis delta as well as a higher rate of HBsAg and HBeAg demonstration in these cells. The authors provide evidence for advisability of the use of BCG vaccine and tactivin in patients with the chronic disease, since they improve macrophagal function, promote the inhibition of HB-virus replication and the onset of a stable remission in patients with chronic hepatitis B and delta.


[The role of echography in the diagnosis of vesico-ureteral reflux in children]. A study was made of alternative potentialities of ultrasonography in the diagnosis of vesicoureteral reflex (VUR) in 137 children (228 kidneys) aged 16 days to 14 years. Routine scanning of the urinary tract was performed; the dynamics of dilatation of the renal pelvis was estimated depending on the degree of the urinary bladder filling and urination; contrast sonography was carried out. Complex ultrasonography was informative in 33% of cases with grade I VUR, in 79% of cases with grade II VUR, and in 100% of cases with grade III-V VUR. It is suggested that in accordance with the ultrasonography data, VUR can be distributed into three main groups.


King's conceptual model and individual psychotherapy. Goal setting is a major component of individual psychotherapy and a concept central to Imogene King's conceptual model of goal attainment. Yet the nursing literature contains no reference to the application of King's model as a framework for conducting individual psychotherapy. Using King's conceptual model, the author describes how the nurse therapist can use the concepts of transactions, interactions, and communication to conduct individual psychotherapy. This author also demonstrates, through use of clinical illustration, the effective application of this nursing model to clinical practice.


The clinical nurse specialist as brief psychotherapist. As managed care continues to flourish, the psychiatric clinical nurse specialist may function as a case manager for a managed care company or as a utilization review nurse for a hospital, community provider, or administrator. Stressing the strengths of the psychiatric clinical nurse specialist as brief therapist, the author reviews elements of the brief treatment model, including assessment, focus of treatment, knowledge of community resources, patient education, group skills, crisis intervention, and treatment planning.


The incest cycle across generations.

The incest cycle across generations. Using the theories of Murray Bowen and the teachings of Joseph Campbell, the author presents a clinical case to demonstrate how generations of sexual abuse led to anxiety symptoms in the offspring. Methods used to obtain and interpret the multigenerational family genogram, and the significance of family myths in sustaining dysfunctional patterns, are reviewed.


Codependency: another name for Bowen's undifferentiated self. Codependency is a term used to describe personality characteristics of people involved in unhealthy relationships. The authors purport that characteristics of codependency can be organized and interpreted using concepts from Bowen's family systems theory. Having such a framework addresses the criticisms that the concept of codependency lacks a solid theoretical foundation. In addition, nurses need to understand the concept if they are to evaluate their own actions regarding codependent behaviors.


Drug transport across the blood-brain barrier. II. Experimental techniques to study drug transport. This is part II of a review on the transport of drugs across the blood-brain barrier. In this part, the emphasis is on the various experimental techniques that can be used to characterize the blood-brain barrier transport of drugs. Generally speaking, three approaches can be distinguished: in vitro techniques using isolated brain capillaries, cerebrovascular endothelial cells in primary culture or endothelium-derived cell lines; in vivo techniques (both single-passage and multi-passage techniques) and in situ perfusion techniques. Each of these techniques has specific advantages and disadvantages associated with it. Therefore, in many instances, a combination of different approaches is needed to study the fundamental aspects of drug transport across the blood-brain barrier.


Administration of oral chloral hydrate to paediatric patients undergoing magnetic resonance imaging. Sedation is frequently required in children undergoing magnetic resonance imaging (MRI). 172 Paediatric patients (82 female and 90 male, age 42 +/- 26 months, weight 14.7 +/- 5.6 kg) entered an open, non-comparative, prospective study to assess the utilization of oral chloral hydrate. Chloral hydrate syrup (70 mg/ml) was administered 20-30 min prior to the procedure. Effective sedation was reached in 80.3% with an average initial dose of 55 mg/kg and in 93.6% with an average total dose of 65 mg/kg. Significant differences in effectivity were correlated with the dose (54 +/- 11 mg/kg in failure cases versus 66 +/- 16 mg/kg in effective cases; p < 0.05) and diagnosis (effectivity falls to 62.5% and 76.0% in children with medullar tumours and encephalic white matter alterations, respectively; p < 0.01). Average sleep induction time was 30 +/- 19 min, and average duration of sleep was 62 +/- 24 min. Adverse reactions occurred in 4.7%, with nausea, vomiting and stomach pain being the most common side-effects (3.5%). Multivariate statistical analysis selects total dose and age into the discriminant function, with a 100% relative percentage of correct classification. A simple method for optimizing the chloral hydrate dose in children is proposed: the dose in mg/kg is calculated as half the age in months + 50.


Women's mental health care--into the '90s. The author asserts that nurses need to understand the various historical, sociological, and cultural factors in society that have influenced the provision of mental health services to women. She claims that, historically, different standards of health have been applied to women than men. Sociologically, stereotypical roles for women have contributed to the low self-esteem, fear of failure, and the passivity often associated with depression in women. Culturally, minorities and the elderly have received bias in the mental health care system. The nurse must understand these factors in order to support purposeful change and to fashion an alternate framework tailored to the specific needs of women.


The orientation phase of the nurse-client relationship: how long does it take? As Hildegard Peplau has established, the orientation phase of the nurse-client relationship represents the first stage of therapeutic work. The author studied the length of the orientation phase with clients with chronic mental illness. Findings suggested that the orientation phase was related to the number and length of hospitalizations, while demographic variables such as psychiatric diagnosis were unrelated to the length of the orientation phase. A return to the orientation phase can be triggered by a change of staff, even for brief periods, or internal factors within the client, such as worsening of paranoia or depression.


Antimicrobial screening of essential oils and extracts of some Humulus lupulus L. cultivars. The essential oils as well as solvent extracts of 11 hop cultivars, 1 hop variety and a wild type of hop were screened for their antimicrobial activities using the agar overlay technique. The oils were isolated from the cones of the various hop plants by hydrodistillation, the extracts were obtained by soaking the hop cones in chloroform. The oils and the extracts showed activity against the Gram-positive bacteria (Bacillus subtilis and Staphylococcus aureus) and the fungus (Trichophyton mentagrophytes var. interdigitale), but almost no activity against the Gram-negative bacterium (Escherichia coli) and the yeast (Candida albicans) used in the screening. The peak area percentages of the main volatile components and the contents of the bitter acids of the extracts were determined for all cultivars using chromatographic methods.


Comparison of costs linked to the preparation and administration of fluorouracil as a continuous infusion based on three techniques. The approach in treatment in medical oncology and particularly in the management of solid tumours has to integrate--at least--two targets: the enhancement of therapeutic efficacy, and the respect of global budget assigned to health. Different teams are implicated in such an approach and especially physicians and pharmacists. We decided to conduct a comparative study of three techniques of administering drugs as a continuous infusion. We analysed time and materials required for the preparation in the centralized preparation unit, and for dispensing and nursing in the health units. The use of programmable pumps (CADD-1) leads to overall saving costs of 27 to 40% compared to administration by means of an infusion bag or a motor-drive syringe.


High pressure liquid chromatographic analysis of the serum concentration of cefuroxime after an intravenous bolus injection of cefuroxime in patients with a coronary artery bypass grafting. A simple reversed-phase high pressure liquid chromatographic method was developed for the determination of cefuroxime in the serum of patients undergoing coronary artery bypass grafting. The serum was cleaned up with a 3.3% solution of perchloric acid in water. Cefalexine was used as an internal standard. Detection was made by a UV multi-wavelength detector. The optimum wavelength for cefuroxime is 275 nm. The absolute recovery of this method was 90.9%; the limit of quantification was 0.7 mg/l. This analytical method was used in a study to investigate the cefuroxime serum concentration--time curves in 26 patients undergoing coronary artery bypass grafting. It was found that one single dose is sufficient to obtain effective serum concentrations.


Stability and compatibility of four anthracyclines: doxorubicin, epirubicin, daunorubicin and pirarubicin with PVC infusion bags. A rapid isocratic technique was developed for the analysis of four anthracyclines (doxorubicin, epirubicin, daunorubicin and pirarubicin) in parenteral solutions using high pressure liquid chromatography (HPLC) with fluorescence detection and a C18 Hypersil ODS column. The availability and compatibility of these drugs from solutions infused via PVC infusion bags through PVC administration sets have been examined. No significant drug loss was observed during simulated infusions (n = 4) for 24 h using PVC infusion bags and administration sets. No significant difference was found between infusion solutions (5% glucose or 0.9% NaCl), except for pirarubicin. The reconstitution of pirarubicin in 0.9% NaCl was impossible, because we observed a precipitation of the compound in solution. The stability of the drugs was also studied in solution, in PVC bags after storage at 4 degrees C with protection from light. The results show the stability of doxorubicin, epirubicin and daunorubicin during 7 days of storage to be satisfactory, irrespective of the infusion solution (5% glucose or 0.9% NaCl). In the case of pirarubicin, the stability of the drug was satisfactory during 5 days of storage in 5% glucose, but beyond, we observed a degradation of the compound with formation of doxorubicin in the infusion solution.


Genome-related datasets within the E. coli Genetic Stock Center database. The contents of the E. coli Genetic Stock Center database and the availability in electronic form of the subset of information most relevant to sequence databases are described. The database uses the long-standing Stock Center records (developed and curated by Dr B.J.Bachmann) in describing genotypes of mutant derivatives of E.coli K-12 in terms of alleles, structural mutations, mating type, and plasmids as well as the derivation, names and originators of the strain, and references. The database includes descriptions of mutations, mutation properties, genes, gene properties, and gene products, with EC number identifiers for enzymes. Sequence information is not included, but entries refer to sequence database accession numbers for sequenced regions. A gene is described as a subtype of a more general category of chromosome interval called Site. Since sites are used to describe any chromosomal interval, mapping information is associated with sites. Alleles are described as mutations of those sites and they are not primary map objects, but inherit map position information from the corresponding site description. The database design is intended to preserve richness of detail where it is known and uncertainty of measurements or information as it occurs in order to represent the stock center records as accurately as possible.


Protein splicing removes intervening sequences in an archaea DNA polymerase. The Vent DNA polymerase gene from Thermococcus litoralis contains two in-frame insertions that must be spliced out to form the mature polymerase. Primer extension and cDNA PCR revealed no evidence of spliced RNA to account for this editing. In contrast, pulse-chase analysis indicated that expression constructs lacking the first insertion produced a protein precursor in Escherichia coli that was processed post-translationally to form polymerase and I-TliI, the endonuclease protein that is the product of the second insertion. At least one intermediate, which migrated more slowly than the precursor and may be branched, was also detected. Amino acid substitutions at the splice junction slowed or blocked the protein splicing reaction. Processing occurs in several heterologous systems, indicating either self-splicing or ubiquitous splicing factors. Processing occurs in a mutant lacking I-TliI endonuclease activity, establishing the independence of splicing and endonuclease activities.


Differences in unwinding of supercoiled DNA induced by the two enantiomers of anti-benzo[a]pyrene diol epoxide. The unwinding of supercoiled phi X174 RFI DNA induced by the tumorigenic (+) and non-tumorigenic (-) enantiomers of trans-7,8-dihydroxy-anti-9,10-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene (BPDE) has been investigated by agarose slab-gel and ethidium titration tube gel electrophoresis. The differences in adduct conformations were verified by flow linear dichroism techniques. Both enantiomers cause a reversible unwinding by the formation of noncovalent intercalative complexes. The effects of covalently bound BPDE residues on the electrophoretic mobilities of the RF I DNA form in agarose gels were investigated in detail in the range of binding ratios rb approximately 0.0-0.06 (covalently bound BPDE residues/nucleotide). In this range of rb values, there is a striking difference in the mobilities of (+)-BPDE- and (-)-BPDE-adducted phi X174 DNA in agarose slab-gels, the covalently bound (+)-BPDE residues causing a significantly greater retardation than (-)-BPDE residues. Increasing the level of covalent adducts beyond rb approximately 0.06 in the case of the (+)-BPDE enantiomer, leads to further unwinding and a minimum in the mobilities (corresponding to comigration of the nicked form and the covalently closed relaxed modified form) at rb 0.10 +/- 0.01; at still higher rb values, rewinding of the modified DNA in the opposite sense is observed. From the minimum in the mobility, a mean unwinding angle (per BPDE residue) of theta = 12 +/- 1.5 degrees is determined, which is in good agreement the value of theta = 11 +/- 1.8 degrees obtained by the tube gel titration method. Using this latter method, values of theta = 6.8 +/- 1.7 degrees for (-)-BPDE-phi X174 adducts are observed. It is concluded that agarose slab gel techniques are not suitable for determining unwinding angles for (-)-BPDE-modified phi X174 DNA because the alterations in the tertiary structures for rb < 0.06 are too small to cause sufficiently large changes in the electrophoretic mobilities. The major trans (+)-BPDE-N2-guanosine covalent adduct is situated at external binding sites and the mechanisms of unwinding are therefore different from those relevant to noncovalent intercalative BPDE-DNA complexes or to classical intercalating drug molecules; a flexible hinge joint and a widening of the minor groove at the site of the lesion may account for the observed unwinding effects. The more heterogeneous (-)-BPDE-nucleoside adducts (involving cis and trans N2-guanosine, and adenosine adducts) are less effective in causing unwinding of supercoiled DNA for reasons which remain to be elucidated.


A mechanism for deletion formation in DNA by human cell extracts: the involvement of short sequence repeats. DNA molecules carrying a site-specific double-strand break were exposed to nuclear extracts from human cell lines. It was shown previously that breaks could be rejoined correctly by human extracts, but that a proportion of the rejoined molecules had suffered deletions and insertions. The 'mis-rejoined' proportion was higher with cell extracts from an individual with the disorder ataxia-telangiectasia than with normal cell extracts. We now show by sequence analysis that deletions in extract-treated molecules occur exclusively between short direct repeats (2-6 base pairs). A mis-rejoined molecule containing an insertion of 300 bp also had a repeat-based deletion at the same site. A number of different direct repeats are involved; however, some clustering of these occurs especially on the upstream side of the initial breakpoint. These data are most simply interpreted in terms of a model of deletion formation involving single-strand exposure and repair, perhaps with the action of other DNA-metabolising enzymes influencing the frequency with which some repeats are involved.


DNA ligase I gene expression during differentiation and cell proliferation. We have studied the regulation of mammalian DNA ligase I gene by using a cDNA probe in Northern blot experiments with RNA extracted from several cell types in different growth conditions. DNA ligase I mRNA is detected in all analysed cell systems, regardless of their proliferation state, including mature rat neurons. A significant increase in DNA ligase I mRNA level is observed when cells are induced to proliferate, in agreement with the raise of DNA joining activity found in the same cell systems. The increase parallels the start of DNA synthesis, but the messenger remains at high level beyond the end of the S phase and is detected also in the presence of aphidicolin. A decrease in DNA ligase I mRNA is observed in HL-60 and NIH-3T3 cells after differentiation. The high stability of DNA ligase I mRNA in both resting and proliferating human fibroblasts suggests a cell proliferation dependent rate of transcription. On the other hand the presence of a basal level of DNA ligase I in nondividing cells, strongly suggests an involvement of this enzyme in DNA repair. This conclusion is supported by a threefold increase in DNA ligase I observed 24 h after UV irradiation of human confluent primary fibroblasts.


Molecular analysis of POP2 gene, a gene required for glucose-derepression of gene expression in Saccharomyces cerevisiae. We have isolated a new mutant of Saccharomyces cerevisiae that exhibits a glucose-derepression resistant (and sucrose-non-fermentor) phenotype. This mutant was obtained by screening for overproduction of alpha-amylase in a strain containing the mouse alpha-amylase gene under the control of the PGK promoter. The mutation designated pop2 (PGK promoter directed over production). The pop2 mutant overproduced amylase 5-6 fold and displayed several other pleiotropic defects: (1) resistance to glucose derepression, (2) temperature-sensitive growth, (3) failure of homozygous diploid cells to sporulate and (4) reduced amount of reserve carbohydrates. We mapped pop2 to chromosome XIV, distal to lys9 and SUP28, indicating that POP2 is a newly-identified locus. We isolated the POP2 gene from two yeast strains of different genetic backgrounds, S288C and A364A, and determined their nucleotide sequences. The predicted amino acid sequence of the POP2 protein contains three glutamine-rich region, a proline-rich region and a serine/threonine-rich region, characteristic of many transcription factors. Steady state levels of RNA transcribed from the PGK-amylase fusion gene and from endogenous PGK gene in stationary-phase pop2 cells were 5- to 10-fold higher than those observed in wild-type cells, showing that the pop2 mutation affects transcription of the PGK gene transcription.


Transcriptional regulation by folate: inducible gene expression in Dictyostelium transformants during growth and early development. The Dictyostelium discoidin genes are induced in bacteria-grown cells shortly before the onset of development but are also highly expressed during growth in axenic medium. We here show that axenically growing cells strongly respond to the extracellular signal folate by suppressing discoidin synthesis while cell growth and development is not substantially affected. Repression occurs via two previously identified promoter elements, the dIE and the dAXE. Removal of the signal molecules or setting cells up for development results in rapid reactivation of the promoter. Based on this observation, we constructed the transformation vector pVEII and describe a convenient method which allows for controlled expression of a gene of interest in growing cells and also for external modulation in early development. Deletion constructs of the discoidin promoter can be used in addition to vary transcriptional activity over about one order of magnitude.


Oligonucleotide labeling methods. 3. Direct labeling of oligonucleotides employing a novel, non-nucleosidic, 2-aminobutyl-1,3-propanediol backbone. Novel CE-phosphoramidite (7a-e) and CPG (8a, c, d, e) reagents have been prepared from a unique 2-aminobutyl-1,3-propanediol backbone. The reagents have been used to directly label oligonucleotides with fluorescein, acridine, and biotin via automated DNA synthesis. The versatile 2-aminobutyl-1,3-propanediol backbone allows for labeling at any position (5', internal, and 3') during solid phase oligonucleotide synthesis. Multiple labels can be achieved by repetitive coupling cycles. Furthermore, the 3-carbon atom internucleotide phosphate distance is retained when inserted internally. Using this method, individual oligonucleotides possessing two and three different reporter molecules have been prepared.


HIV-1 promotor insertion revealed by selective detection of chimeric provirus-host gene transcripts. To study host gene activation by retroviral promotor insertion, a polymerase chain reaction (PCR) assay was developed. This method allows a sensitive and selective detection of chimeric provirus-host gene transcripts, hallmarks of insertional activation events, which does not rely on an induction of tumor cell growth. We analysed HIV-1 infected cells of a CD4+ T-cell line (H9), infected peripheral blood mononuclear cells and cells in broncho-alveolar washes of AIDS patients. In each case, a variety of chimeric mRNA molecules were detected using a PCR amplification reaction and 5' primers specific to the HIV-1 LTR and 3' primers specific to poly A of mRNA. In infected H9 lymphocytes, a mRNA was identified encoding a putative protein of 145 amino-acids that was not expressed in uninfected H9 cells. This shows for the first time that HIV-1 can activate transcription of host cellular genes by promotor insertion in a fashion similar to slow-transforming avian and murine retroviruses.


Structure and evolution of the XcyI restriction-modification system. The XcyI restriction-modification system from Xanthomonas cyanopsidis recognizes the sequence, CCCGGG. The XcyI endonuclease and methylase genes have been cloned and sequenced and were found to be aligned in a head to tail orientation with the methylase preceding and overlapping the endonuclease by one base pair. The nucleotide sequence codes for an N4 cytosine methyltransferase with a predicted molecular weight of 33,500 and an endonuclease comprised of 333 codons and a molecular weight of 36,600. Sequence comparisons revealed significant similarity between the XcyI, CfrI and SmaI methylisomers. In contrast, no similarity was detected between the primary structures of the XcyI and SmaI endonucleases. The XcyI restriction-modification system is highly homologous to the XmaI genes, although the DNA sequences flanking the genes rapidly diverge. The sequence of the XcyI endonuclease contains two motifs which have recently been identified as essential to the activity of the EcoRV endonuclease.


Domains required for nucleic acid binding activities in chloroplast ribonucleoproteins. Five ribonucleoproteins (or RNA-binding proteins) from tobacco chloroplasts have been identified to date; each of these contains an acidic N-terminal domain (24-64 amino acids) and two conserved RNA-binding domains (82-83 amino acids). All five ribonucleoproteins can bind to ssDNA and dsDNA but show high specificity for poly(G) and poly(U). Here we present the nucleic acid binding activity of each domain using a series of deletion mutant proteins made in vitro from the chloroplast 29 kDa ribonucleoproteins. The acidic domain does not have a positive effect on binding activities and proteins lacking this domain show higher affinities for nucleic acids than the wild-type proteins. Mutant proteins containing single RNA-binding domains can bind to poly(G) and poly(U), though with lower affinities than proteins containing two RNA-binding domains. The spacer region (11-37 amino acids) between the two RNA-binding domains does not interact with poly(G) or poly(U) by itself, but is required for the additive activity of the two RNA-binding domains. Proteins consisting of two RNA-binding domains but lacking the spacer have the same activity as those containing only one RNA-binding domain. Possible roles for each domain in chloroplast ribonucleoproteins are discussed.


Targeting of Sp1 to a non-Sp1 site in the human neurofilament (H) promoter via an intermediary DNA-binding protein. The human neurofilament (H) promoter contains multiple binding sites for nuclear proteins including a Proximal (Prox) site centered around the sequence GGTTGGACC and an adjacent pyrimidine (Pyr) tract site centered around the sequence CCCTCCTCCCC. Surprisingly binding to a probe containing the Prox/Pyr region of the NF(H) promoter was competed in gel shifts by an oligonucleotide containing only an Sp1 binding site (GGGGCGGGG). Supershift assays with a polyclonal anti-Sp1 antisera confirmed that Sp1 was part of the complex formed with the Prox/Pyr probe. However neither bacterially expressed Sp1 516C or vaccinia virus expressed full-length Sp1 778C bound to the Prox or Pyr sequences in DNase I footprints or gel shift assays. Gel shift competitions and supershift assays with probes containing either Prox or Pyr tract sites alone demonstrated targeting of Sp1 to the Prox binding site and identified a non-Sp1 containing complex which contains a Prox binding protein. Adding exogenous Sp1 to a HeLa nuclear extract enhanced the Sp1-containing complex but had no effect on the Prox complex. These studies show that Sp1 can be targeted to a non-Sp1 site in the human NF(H) promoter through protein/protein interactions with a distinct sequence specific DNA-binding protein.


A transgenic mouse that expresses a diversity of human sequence heavy and light chain immunoglobulins. We have generated transgenic mice that express a diverse repertoire of human sequence immunoglobulins. The expression of this repertoire is directed by light and heavy chain minilocus transgenes comprised of human protein coding sequences in an unrearranged, germ-line configuration. In this paper we describe the construction of these miniloci and the composition of the CDR3 repertoire generated by the transgenic mice. The largest transgene discussed is a heavy chain minilocus that includes human mu and gamma 1 coding sequences together with their respective switch regions. It consists of a single 61 kb DNA fragment propagated in a bacterial plasmid vector. Both human heavy chain classes are expressed in animals that carry the transgene. In light chain transgenic animals the unrearranged minilocus sequences recombine to form VJ joints that use all five human J kappa segments, resulting in a diversity of human-like CDR3 regions. Similarly, in heavy chain transgenics the inserted sequences undergo VDJ joining complete with N region addition to generate a human-like VH CDR3 repertoire. All six human JH segments and at least eight of the ten transgene encoded human D segments are expressed. The transgenic animals described in this paper represent a potential source of human sequence antibodies for in vivo therapeutic applications.


The isolation of transcription factors from lambda gt11 cDNA expression libraries: human steroid 5 alpha-reductase 1 has sequence-specific DNA binding activity. The Surf-1/Surf-2 bi-directional promoter contains binding sites for at least three transcription factors (Su1, Su2, and Su3). By screening a lambda gt11 HeLa cell cDNA expression library with a concatenated Su2 factor binding site, we isolated a cDNA which encodes a protein with sequence-specific DNA binding activity. Gel retardation assays showed that the cloned factor binds specifically to the Su2 factor binding site present in the human Surf-1/Surf-2 promoter but not to an Su2 site containing mutated base pairs. Co-transfection experiments demonstrated that the cloned cDNA had little or no effect on the expression of a reporter gene under the control of multiple Su2 factor binding sites. Similarly a fusion protein in which the acidic activation domain of HSV VP16 was linked to the cloned factor had no effect, implying that the factor does not function as a DNA binding protein in vivo. DNA sequence analysis revealed that the cloned cDNA is identical to that of human steroid 5 alpha-reductase 1, an enzyme which converts testosterone to dihydrotestosterone. These results are discussed with respect to other putative transcription factors which have been isolated from cDNA expression libraries on the basis of their sequence-specific DNA binding activity.


RNA-primed complementary-sense DNA synthesis of the geminivirus African cassava mosaic virus. The plant DNA virus African cassava mosaic virus (ACMV) is believed to replicate by a rolling circle mechanism. To investigate complementary-sense DNA (lagging strand) synthesis, we have analysed the heterogenous form of complementary-sense DNA (H3 DNA) from infected Nicotiana benthamiana by two-dimensional agarose gel electrophoresis and blot hybridisation. The presence of an RNA moeity is demonstrated by comparison of results for nucleic acids resolved on neutral/alkaline and neutral/formamide gels, suggesting that complementary-sense DNA synthesis on the virus-sense single-stranded DNA template is preceded by the synthesis of an RNA primer. Hybridisation with probes to specific parts of ACMV DNA A genome indicates that synthesis of the putative RNA primer initiates between nucleotides 2581-221, a region that includes intergenic sequences that have been implicated in geminivirus DNA replication and the control of gene expression.


Determination of recognition-sequences for DNA-binding proteins by a polymerase chain reaction assisted binding site selection method (BSS) using nitrocellulose immobilized DNA binding protein. We have developed a simple procedure for rapid determination of a DNA sequence recognized by a DNA binding protein based on immobilization of the protein on nitrocellulose filters. The procedure consists of the following steps: A recombinant protein with a functional DNA binding domain is expressed in E. coli. The protein is purified to homogeneity, immobilized on nitrocellulose paper, and exposed to a pool of double stranded oligonucleotides carrying in the central part a 20 bp random sequence, which is flanked by conserved sequences with restriction endonuclease recognition sites for analytical and subcloning purposes and sequences complementary to polymerase chain reaction primers. Oligonucleotides retained by the DNA-binding protein are liberated by increasing the ionic strength and used in a new binding process after amplification by the polymerase chain reaction technique. Finally the amplified product is cloned for determination of the DNA sequence selected by the DNA-binding protein. Murine Zn-finger and basic helix-loop-helix DNA binding proteins were used to demonstrate the efficiency of the method. We show that the yield of oligonucleotides binding to the protein was increased by several consecutive rounds of filter binding and amplification, and that the protein extracted a specific sequence from the pool of random oligonucleotides.


The yeast nuclear gene MRF1 encodes a mitochondrial peptide chain release factor and cures several mitochondrial RNA splicing defects. We report the molecular cloning, sequencing and genetic characterization of the first gene encoding an organellar polypeptide chain release factor, the MRF1 gene of the yeast Saccharomyces cerevisiae. The MRF1 gene was cloned by genetic complementation of a respiratory deficient mutant disturbed in the expression of the mitochondrial genes encoding cytochrome c oxidase subunit 1 and 2, COX1 and COX2. For COX1 this defect has been attributed to an impaired processing of several introns. Sequence analysis of the MRF1 gene revealed that it encodes a protein highly similar to prokaryotic peptide chain release factors, especially RF-1. Disruption of the gene results in a high instability of the mitochondrial genome, a hallmark for a strict lesion in mitochondrial protein synthesis. The respiratory negative phenotype of mrf1 mutants lacking all known mitochondrial introns and the reduced synthesis of mitochondrial translation products encoded by unsplit genes confirm a primary defect in mitochondrial protein synthesis. Over-expression of the MRF1 gene in a mitochondrial nonsense suppressor strain reduces suppression in a dosage-dependent manner, shedding new light on the role of the '530 region' of 16S-like ribosomal RNA in translational fidelity.


The protein sequence and some intron positions are conserved between the switching gene swi10 of Schizosaccharomyces pombe and the human excision repair gene ERCC1. The switching gene swi10+ has a function in mating-type switching as well as in the repair of radiation damages. We have cloned the genomic swi10+ gene by functional complementation of the switching defect of the swi10-154 mutant. The swi10+ gene is not essential for viability. The DNA sequence revealed an open reading frame of 759 nucleotides interrupted by three introns of 127, 52 and 60 bp, respectively. The positions of intron I as well as of intron III of swi10 are evolutionary conserved in comparison to the introns III and IV of the human ERCC1 gene. The analysis of cDNA clones isolated by PCR amplification confirmed the structure of the swi10 gene. The putative Swi10 protein has homologies to the human and mouse ERCC1 protein, to Rad10 of Saccharomyces cerevisiae and to parts of UvrA and UvrC of E. coli. All these proteins are essential components for excision repair of damaged DNA. The Swi10 protein contains a putative DNA binding domain previously found in other proteins. Northern blot experiments and the analyses of cDNA clones indicate that intron I of the swi10 gene is not efficiently spliced.


Organization of the unr/N-ras locus: characterization of the promoter region of the human unr gene. Investigations of the structure and expression of the N-ras gene in mammals has led to the identification of another gene designated unr, which is located immediately upstream of N-ras. These two genes are transcribed in the same orientation and the intergenic distance is of the order of 150 nucleotides. This genetic organization has been observed in the genome of guinea pig, rat, mouse and man with a very high level of sequence conservation in the intergenic region. This unusual gene clustering suggests that the transcriptional regulation of this locus could involve common regulatory sequences as well as transcriptional interference between the two genes. In this study, we have isolated and characterized the human unr promoter. A cluster of transcription initiation sites was mapped by primer extension and RNase protection and shown to be located in a CpG island devoid of TATA and CAAT boxes. Functional organization of the promoter was investigated by measuring the ability of a set of 5' deletions within a1 kb promoter region to drive the expression of the luciferase gene. These studies indicated a very strong promoter activity in NIH 3T3 cells and the presence of positive and negative regulatory domains. Nevertheless, a 90 bp fragment showed the same level of promoter activity as the 1 kb fragment. We also showed that ras genes can transactivate the unr promoter activity and that the 90 bp fragment responded to this transactivation.


Repair synthesis by human cell extracts in cisplatin-damaged DNA is preferentially determined by minor adducts. During reaction of cis-diamminedichloroplatinum(II) (cis-DDP) with DNA, a number of adducts are formed which may be discriminated by the excision-repair system. An in vitro excision-repair assay with human cell-free extracts has been used to assess the relative repair extent of monofunctional adducts, intrastrand and interstrand cross-links of cis-DDP on plasmid DNA. Preferential removal of cis-DDP 1,2-intrastrand diadducts occurred in the presence of cyanide ions. In conditions where cyanide treatment removed 85% of total platinum adducts while approximately 70% of interstrand cross-links remained in plasmid DNA, no significant variation in repair synthesis by human cell extracts was observed. Then, we constructed three types of plasmid DNA substrates containing mainly either monoadducts, 1,2-intrastrand cross-links or interstrand cross-links lesions. The three plasmid species were modified in order to obtain the same extent of total platinum DNA adducts per plasmid. No DNA repair synthesis was detected with monofunctional adducts during incubation with human whole cell extracts. However, a two-fold increase in repair synthesis was found when the proportion of interstrand cross-links in plasmid DNA was increased by 2-3 fold. These findings suggest that (i) cis-DDP 1,2-intrastrand diadducts are poorly repaired by human cell extracts in vitro, (ii) among other minor lesions potentially cyanide-resistant, cis-DDP interstrand cross-links represent a major lesion contributing to the repair synthesis signal in the in vitro assay. These results could account for the drug efficiency in vivo.


V-src-induced-transcription of the avian clusterin gene. We have isolated the avian gene T64 corresponding to the mammalian clusterin, on the basis of high accumulation of its template mRNA in cells infected with oncogenic retroviruses. Since the clusterin was shown to have a protective effect against the immune system, its induction by oncogenic viruses is of major biological importance. The unique, short 5 kb-long T64 genomic locus is inactive in normal quail embryo fibroblasts in primary culture whereas it shows a high transcriptional activity after transformation by the Rous sarcoma virus. The 963 bp-long 5' flanking region is sufficient to drive the transcription of the chloramphenicol acetyltransferase reporter gene in a thermodependent manner when a thermosensitive version of pp60v-src is used. Deletion and point mutation analyses of the promoter show that the v-src response requires at least two separate elements: PUR and AP-1, located respectively at positions -167 to -152 and -25 to -19 relative to the single transcription initiation site. In addition, the binding of specific nuclear factors to these responsive elements correlates with the T64 promoter activation.


POU domain transcription factors from different subclasses stimulate adenovirus DNA replication. POU domain proteins constitute a family of eukaryotic transcription factors that exert critical functions during development. They contain a conserved 160 amino acids DNA binding domain, the POU domain. Genetic data have demonstrated that some POU domain proteins are essential for the proliferation of specific cell types, suggesting a possible role in DNA replication. In addition, the ubiquitous POU transcription factor Oct-1 or its isolated POU domain enhances adenovirus DNA replication. Here we compared the DNA binding specificities of POU domain proteins from different subclasses. They exhibit overlapping, yet distinct binding site preferences. Furthermore, purified Pit-1, Oct-1, Oct-2, Oct-6, Oct-4 and zebrafish POU[C] could all stimulate adenovirus DNA replication in a reconstituted in vitro system. Thus, activation appears to depend on a property common to most POU domain proteins. Adenovirus DNA replication is also stimulated by the transcription factor NFI/CTF. In contrast to NFI, the POU domain did not enhance binding of precursor terminal protein-DNA polymerase to the origin nor did it stabilize the preinitiation complex. These results suggest that the POU domain acts on a rate limiting step after formation of the preinitiation complex.


Analysis of erythroid nuclear proteins binding to the promoter and enhancer elements of the chicken histone H5 gene. The chicken erythroid proteins binding to the histone H5 5' promoter and 3' erythroid-specific enhancer regions were identified. In DNase I footprinting and gel mobility shift experiments with immature adult erythrocyte nuclear extracts, we have demonstrated the binding of proteins to the GC-box, a high affinity Sp1 binding site, and to the upstream promoter element. We have previously demonstrated that a multisubunit complex containing the transcription factor GATA-1 was associated with the enhancer. Here, we show that the enhancer region also has four Sp1 binding sites (one medium and three weak affinity, one of which may also bind the CACCC factor), a potential NF-E4 binding site, and a binding site for a NF1-like factor. The results of gel mobility-shift and competition experiments provide evidence that the Sp1 binding sites are associated with a high molecular mass (greater than 450 kDa), Sp1 containing protein complex. We propose that Sp1 multimers bound at the promoter and enhancer interact to mediate the juxta-positioning of the enhancer and promoter elements, bringing the GATA-1 multisubunit complex next to the initiation site. The GATA-1 complex may contribute to the protein-protein interactions between the enhancer and promoter.


The I-CeuI endonuclease recognizes a sequence of 19 base pairs and preferentially cleaves the coding strand of the Chlamydomonas moewusii chloroplast large subunit rRNA gene. The I-CeuI endonuclease is a member of the growing family of homing endonucleases that catalyse mobility of group I introns by making a double-strand break at the homing site of these introns in cognate intronless alleles during genetic crosses. In a previous study, we have shown that a short DNA fragment of 26 bp, encompassing the homing site of the fifth intron in the Chlamydomonas eugametos chloroplast large subunit rRNA gene (Ce LSU.5), was sufficient for I-CeuI recognition and cleavage. Here, we report the recognition sequence of the I-CeuI endonuclease, as determined by random mutagenesis of nucleotide positions adjacent to the I-CeuI cleavage site. Single-base substitutions that completely abolish endonuclease activity delimit a 15-bp sequence whereas those that reduce the cleavage rate define a 19-bp sequence that extends from position -7 to position +12 with respect to the Ce LSU.5 intron insertion site. As the other homing endonucleases that have been studied so far, the I-CeuI endonuclease recognizes a non-symmetric degenerate sequence. The top strand of the recognition sequence is preferred for I-CeuI cleavage and the bottom strand most likely determines the rate of double-strand breaks.


Infants with single umbilical artery studied in a national registry. 2: Survival and malformations in infants with single umbilical artery. Registry data on all infants born in Sweden between 1983 and 1986 are reviewed to describe perinatal mortality and malformation rate of infants with single umbilical artery (SUA). Since SUA is much more common in infants with chromosomal anomalies and in twins this analysis is confined to the 1694 singletons who were not recorded as having chromosomal anomalies. There was significantly increased risk of perinatal mortality among these infants largely due to an increased frequency of congenital malformations, low birthweight and preterm delivery. Nevertheless, at least 36% of the perinatal mortality occurred in the absence of malformations or low birthweight. We found the overall risk of severe malformation in SUA infants to be increased 4.3 times. Some malformations were especially common, such an anorectal atresia and oesophageal atresia.


Ethnic variation in postnatal assessments of gestational age: a reappraisal. While the possibility of an ethnic bias in postnatal assessments of gestational age has been suggested by several investigators, others have reported that postnatal assessments do not provide biased estimates in non-White ethnic groups. In the light of this ongoing controversy, this study examines the validity of the Ballard postnatal assessment of gestational age by ethnicity, using a relatively large hospital data base that allows for the inspection of ethnic variations in the agreement between the Ballard assessment and last menstrual period (LMP). The results indicate that there is a greater over-estimation of the LMP interval by the Ballard method in Blacks compared with Whites and suggest that systematic differences exist by ethnicity of mother in the agreement between the Ballard postnatal assessment and the LMP interval. After taking maternal characteristics and pregnancy complications into account, for a given gestational age interval, Blacks have on average a greater level of maturity as measured by Ballard. One interpretation of these findings is that postnatal assessments may provide biased over-estimates of the LMP gestational age interval in certain ethnic groups. An alternative interpretation of these data is that the gestational age interval based on LMP is not a valid indicator of fetal maturity, readiness for birth and infant risk status across all ethnic groups.


Evaluation of care for the preterm infant: review of literature on follow-up of preterm and low birthweight infants. Report from the collaborative Project on Preterm and Small for Gestational Age Infants (POPS) in The Netherlands. Since the introduction of neonatal intensive care in the 1960s, mortality in very preterm and very low birthweight infants has been decreasing steadily. Consequently, interest in the outcome of surviving infants is growing. Restriction of health care resources has stressed the need for information concerning the effect of individual treatment components on mortality and morbidity. Concern about the quality in apparently normal survivors has been increasing as well. The current flood of papers on these subjects illustrates the interest in these issues. The first part of this paper reviews the methodology used in follow-up studies in the past decades. It aims at methodological problems that hamper comparison between studies and preclude unequivocal conclusions. New treatment techniques seldom were but should be evaluated by randomised trials. To monitor the combined effects of changing obstetric and neonatal techniques on perinatal outcome, studies in geographically defined populations are recommended using data from early pregnancy until at least preschool age. Comparability of outcomes could be enhanced by international agreement on standardisation of assessment methods and outcome measures. In the second part the results concerning gestational age- and birthweight-specific mortality, impairments and disabilities and the risk factors for such disorders are discussed. Increased survival of even the tiniest infants is clearly established. This increase in survival has not yet been accompanied by an apparent increase in major morbidity. However, many minor impairments are reported, occurring often in combination and predisposing these children to deviations of normal development. Important changes in the manifestation of brain damage appear to occur during development. These findings stress the importance of long-term follow-up studies.


Monoclonal antibodies in hapten immunoassays. This review deals with the potency of monoclonal antibodies (MAbs) to haptens in immunoassays. Specificity and affinity of MAbs to haptens are the major determinants to be considered. Specificity of MAbs depends on the selection of the hapten coupling site to the carrier protein and the antigen used for the screening of MAbs. Nevertheless, cross-reactivity can occur with compounds related to the hapten. This polyspecificity may be circumvented with the use of many MAbs, as has been demonstrated for MAbs to cyclosporine. Affinity of MAbs to haptens is often lower than that of corresponding polyclonal antibodies (PAbs), thereby limiting assay sensitivity. Low affinity is more frequently observed with low molecular weight (100-300) haptens than with larger haptens, such as digoxin or cyclosporine. Affinity enhancement by increasing resemblance to the immunogen can be effective in resolving the lack of sensitivity. With suitable selection strategies. MAbs exhibit real advantages over classical PAbs to haptens because large amounts of worldwide standardized reagents can be prepared.


An alternative approach for assessment of rate of absorption in bioequivalence studies. The partial area method was investigated for evaluation of equivalency in the rate of absorption of immediate release formulations. The applicability of the method was demonstrated with four drugs with different pharmacokinetic/pharmacodynamic characteristics. The confidence interval approach currently employed for bioequivalence determinations was applied to the relevant absorption parameters, including Cmax and partial AUCs. The method was found to be more discriminating than Cmax and/or Tmax in the evaluation of the absorption rate of drugs. The cutoff time or point for partial AUC calculation may vary with the type of drug under study, depending on its clinical use and onset of action. The method was shown to be useful in the assessment of rate of absorption in bioequivalence studies.


Identification of sites of degradation in a therapeutic monoclonal antibody by peptide mapping. A peptide mapping procedure was developed to locate regions of a monoclonal antibody, OKT3, that undergo chemical modification as the molecule degrades upon storage. The structures of these peptide degradation products were investigated. Deamidation at specific asparagine residues and oxidation of a cysteine and several methionines were found to be major routes of OKT3 degradation. A unique chain cross-linked degradation product was also observed and characterized. Changing the storage conditions of the antibody affected the relative distribution of degradation products. These results were useful in the development of more stable formulations for OKT3, and the methods can be used in the characterization of other monoclonal antibodies intended for therapeutic use.


Localization of binding sites for epidermal growth factor (EGF) in rat kidney: evidence for the existence of low affinity EGF binding sites on the brush border membrane. We investigated the renal distribution of 125I-EGF in the filtering perfused rat kidney using an acid washing technique. Trichloroacetic acid-precipitable 125I-EGF radioactivity was eluted from both the renal vein and the urinary cannulae, the former regarded as representing the antiluminal, and the latter the luminal, cell surface bound 125I-radioactivity. The addition of excess unlabeled EGF (20 nM) to the perfusate completely inhibited the binding of 125I-EGF to the antiluminal membrane but did not inhibit that of 125I-EGF to the luminal membrane. On the other hand, the order of relative density of 125I-EGF binding sites in the in vivo kidney determined by autoradiography was cortex > inner medulla > outer medulla. After the i.v. administration of excess unlabeled EGF together with 125I-EGF, the renal uptake of 125I-EGF was inhibited completely in the inner medulla, but only by 50% in the cortex and outer medulla, suggesting the presence of nonsaturable luminal uptake of EGF in the cortex and outer medulla. After i.v. administration of 125I-EGF, a change in position of silver grains from the luminal cell surface membrane to the intracellular space was observed in the proximal convoluted tubules. In conclusion, in addition to the previously identified uptake mechanisms of circulating EGF through high-affinity binding sites on the antiluminal cell surface membrane, the reabsorption mechanism of filtered EGF through low-affinity binding sites on the luminal cell surface membrane was demonstrated. In vivo autoradiography showed the gradual internalization of EGF from the luminal cell surface membrane to the intracellular space of the proximal convoluted tubule.


Skin alteration and convective solvent flow effects during iontophoresis. II. Monovalent anion and cation transport across human skin. Total flux enhancement of ions during iontophoresis is due primarily to the electrochemical potential gradient. However, secondary effects such as convective solvent flow and, in biological membranes, permeability increases as a result of applied field may also contribute to flux enhancement. The modified Nernst-Planck theory includes a solvent flow velocity term and predicts that the flux of uncharged molecules is enhanced or retarded depending on the polarity of the applied field. Polarity-dependent solvent flow velocity, as measured by the flux enhancement of mannitol, has been demonstrated in human epidermal membrane during iontophoresis. In the present study, the solvent flow velocity effects on the flux enhancement of a model cation (tetraethylammonium ion) and a model anion (salicylate ion) across human epidermal membrane were examined. The contribution of membrane alterations, due to the applied field, on overall ion flux was also considered. Solvent flow was found to have a small effect on the flux enhancement of both ions. However, membrane alterations were found to increase greatly the flux of the ionic species. Alterations in the epidermal membrane occurred at the highest voltage investigated (1000 mV) and appeared to reverse over time as indicated by the current and transport data.


Noninvasive in vivo percutaneous absorption measurements using X-ray fluorescence. X-ray fluorescence (XRF) has been used to determine in vivo the percutaneous absorption of 5-iodouracil (5IU) in dimethyl sulfoxide (DMSO) on female Sprague-Dawley rats. An average absorption rate constant of 122 +/- 34 micrograms/cm2-hr was obtained from the XRF measurements on four rats. A comparative study was performed with radiolabeled (125I) 5IU in which the absorption rate constant was determined to be 126 +/- 20 micrograms/cm2-hr. The XRF system described provides a simple, noninvasive means of measuring the percutaneous absorption rate of select compounds by the surface disappearance method.


Lamellar structures formed by stratum corneum lipids in vitro: a deuterium nuclear magnetic resonance (NMR) study. Hydrated lipid mixtures consisting of stratum corneum ceramides, cholesterol, specifically deuterated palmitic acid, and cholesteryl sulfate were investigated by solid-state 2H NMR spectroscopy at different temperatures. The mole ratio of cholesterol to ceramides was varied from 1 to 0. 2H NMR spectra from these mixtures showed powder patterns with quadrupolar splittings smaller than those obtained from control mixtures containing dipalmitoylphosphatidylcholine (DPPC) instead of the ceramides. This result is attributed to the rigid amide group of the ceramides, with a planar configuration, which could prevent close packing of the alpha-methylenes of the acyl chains. There was a gradual loss of symmetry in the powder pattern as the amount of cholesterol was decreased and the amount of ceramides (or DPPC) was increased concomitantly. The loss was more pronounced in the ceramide-containing samples. This phenomenon is interpreted as a decrease in the axial reorientation rate of the alpha-deuterated palmitic acid in the bilayers, presumably caused by the increased hydrogen bonding resulting from the high amount of hydroxyl-bearing ceramides. Spectra obtained at temperatures above 60 degrees C indicated the formation of a hexagonal phase (HII) by the ceramide-containing mixtures. Spectra of the omega-deuterated palmitic acid in the mixture containing 76 mol% ceramides and no cholesterol indicated phase separation into a more rigid phase and a more mobile phase in the temperature range of 25 to 60 degrees C. The bilayer configuration of lipids at 25 degrees C was confirmed by thin-section electron microscopy.


Local enhanced topical delivery (LETD) of drugs: does it truly exist? There is considerable uncertainty over whether and to what extent topically applied drugs can be delivered directly to anatomical sites beneath the skin, without prior entry into the systemic blood circulation. The in vivo studies reported in this work were designed to assess whether local enhanced topical delivery (LETD) can be achieved with piroxicam, a nonsteroidal antiinflammatory drug. Equivalent doses of tritium-labeled drug were administered by the i.v. or topical routes to male rats. The topical plasma profile reveals a maximum concentration (Cpmax) at 12 hr, compared to a typical, multiexponential decline in plasma concentration after i.v. dosing. All four muscles from the topically dosed shoulder exhibit two distinct peaks, the first at 4 hr and a later one at 12 hr (which coincides with the topical Cpmax). The contralateral muscles from the nondosed shoulder, in contrast, produce only a single peak at 12 hr after topical dosing. After the i.v. administration of piroxicam, the concentration-time profiles for each muscle closely parallel that seen for the i.v. plasma. Tissue-to-plasma ratios (T/P) show that the topical nondosed and the i.v. muscles are nearly constant over the entire time course of this study, indicating a pseudo-equilibrium between the plasma and those muscles. However, the early T/P ratios for the topically dosed muscles are markedly elevated and gradually decline to a constant value only after 12 hr, indicating that a similar pseudo-equilibrium is not established in this case. Thus, these results strongly imply that the topical administration of a drug can lead to LETD for tissues subjacent to the skin.(ABSTRACT TRUNCATED AT 250 WORDS)


Physicochemical properties of salts of p-aminosalicylic acid. I. Correlation of crystal structure and hydrate stability. The potassium (K), sodium (NA), calcium (CA), and magnesium (MG) salts of p-aminosalicylic acid were obtained, and their thermal behavior was characterized by means of differential scanning calorimetry (DSC) and thermogravimetric analysis (TG). Their crystal and molecular structures were determined by single-crystal X-ray diffraction after powder patterns had shown them to be nonisomorphous. Different degrees of hydration were observed for the solid salts, and an assessment of hydrate stability to dehydration was made from thermogravimetric studies. The onset temperature of dehydration (Tt) of each salt varied within the series and exhibited correlation with X-ray determined structure. The observed onset of dehydration of MG and CA was higher than that of NA and is consistent with stronger ion-dipole interactions for the divalent salts. Crystallographic determination of the bond lengths between the metal ion and the water oxygens were 2.4 and 2.9 A for NA, between 2.0 and 2.1 A for MG, and 2.4 A for CA. The open nature and presence of a channel feature in the structure of the sodium salt may have facilitated escape of water molecules from the crystal. Particle presentation (e.g., size, crystallinity) was also shown to affect dehydration behavior.


In vivo evaluation of enteric-coated naproxen tablets using gamma scintigraphy. Seven healthy, male volunteers were entered into a randomized, open crossover study of the gastrointestinal transit of two enteric-coated 500-mg naproxen tablets. Two radiolabeled tablets were given to each volunteer on two occasions separated by 7 days, once in the fasted state and once after breakfast. Radiolabeling of tablets was achieved by the incorporation of samarium-152 oxide during manufacture, followed by neutron activation of the tablet to produce the gamma-emitting isotope samarium-153. No loss of tablet integrity was seen in the stomach and all tablets disintegrated in the small intestine. Onset of tablet disintegration was controlled predominantly by gastric emptying. Time in the small intestine prior to tablet disintegration was independent of food intake. Naproxen blood levels with time were consistent with the delayed release of naproxen from the tablets. Overall, transit, disintegration, and absorption were as expected from an enteric-coated tablet.


Distribution and elimination of the glycosidase inhibitors 1-deoxymannojirimycin and N-methyl-1-deoxynojirimycin in the rat in vivo. We studied the pharmacokinetics of two synthetic derivatives of 1-deoxynojirimycin in the rat after intravenous administration. The mannosidase IA/B inhibitor 1-deoxymannojirimycin and the glucosidase inhibitor N-methyl-1-deoxynojirimycin exhibited minimal plasma protein binding and showed a rapid biphasic plasma disappearance, with an initial t1/2 of 3.0 and 4.5 min, respectively, and a terminal t1/2 of 51 and 32 min, respectively. For both compounds renal excretion is the major route of elimination. After 120 min, 52% of the dose of 1-deoxymannojirimycin and 80% of the dose of N-methyl-1-deoxymannojirimycin was recovered unchanged from the urine, whereas only 4.9 and 0.2%, respectively, of the dose was excreted in bile. Urinary clearance of 1-deoxymannojirimycin was similar to the glomerular filtration rate. In contrast, urinary clearance of N-methyl-1-deoxynojirimycin was two to three times higher than the glomerular filtration rate, indicating active tubular secretion. Ligation of the renal vessels decreased the total-body clearance of 1-deoxymannojirimycin and N-methyl-1-deoxynojirimycin 18- and 24-fold, respectively. Neither alkalinization of the urine by infusion of bicarbonate solutions nor forced diuresis altered the renal excretion rate of these compounds, implying the absence of tubular reabsorption. At 120 min, the amounts of 1-deoxymannojirimycin in liver and kidney were 2.1 and 1.1% of the dose, respectively, while small intestine, stomach, and heart contained only 0.9, 0.6 and 0.1%. Less than 1% of the dose of N-methyl-1-deoxynojirimycin was found in the collected organs 2 hr after injection.(ABSTRACT TRUNCATED AT 250 WORDS)


Pharmacokinetic disposition of multiple-dose transdermal nicotine in healthy adult smokers. The pharmacokinetics and cardiovascular effects of nicotine and its major metabolite, cotinine, were characterized during repeated once-daily application for 5 days of a 30-cm2 nicotine transdermal system, Nicotine TTS (Habitrol), to nine healthy, black, adult, male smokers. Subjects abstained from smoking throughout the study. Pharmacokinetic analysis indicated that nicotine was delivered from Nicotine TTS for the 24-hr application period averaging 0.76 mg/cm2/24 hr, and at a relatively constant rate compared to other modes of drug administration. The transdermal clearance of nicotine, 1351 ml/min, coincided with reported values following intravenous nicotine administration; however, the terminal-phase half-life, 5.0 hr, did not. An analysis of the components of variance contributing to the variability in nicotine delivery from repetitive application of Nicotine TTS indicated that the in vivo transdermal permeation of nicotine is rate limited by both the device and the intrinsic skin conductivity. Clinical cardiovascular side effects were negligible as an apparent result of subclinical vasopressive nicotine concentrations, although drug activity with regard to other effects was manifested.


Age and the pharmacokinetic-pharmacodynamic relationship of phenobarbital in rats: "pseudo"-longitudinal vs cross-sectional study design. In a previous study, an apparent age-related increase in brain sensitivity to the anesthetic effect of phenobarbital was observed in BN/BiRij rats. However, since this study was conducted according to a cross-sectional design, the observed change could, in principle, also have been the result of a cohort effect. The purpose of the present investigation was to exclude the role of such a cohort effect by adopting a "pseudo"-longitudinal study design. In this design 45 animals out of one cohort were reserved, and one subgroup was investigated at five ages (7, 14, 21, 29, and 34 months). A decrease in the anesthetic threshold dose of phenobarbital was found during aging, which appeared to be due mainly to an increase in the brain sensitivity. It is concluded that the previously observed increase in brain sensitivity is indeed the result of the aging process rather than a cohort effect.


Glutathione S-transferase-mediated metabolism of glyceryl trinitrate in subcellular fractions of bovine coronary arteries. The possible role of glutathione S-transferases (GTSs) in vascular glyceryl trinitrate (GTN) metabolism was investigated. GTN degradation to form its dinitrate metabolites (GDNs) in the 9000g (9k) supernatant fraction of bovine coronary arteries (BCA) was examined. BCAs were homogenized with a 3x volume of phosphate buffer, and the 9k fraction was obtained by centrifugation. GTN (40 ng/ml; 1.76 x 10(-7) M) was incubated for 2 hr in the 9k fraction of BCA in the presence of reduced glutathione (2 x 10(-3) M). Samples were taken at 10, 20, 40, 60, and 120 min. GTN was observed to degrade readily, exhibiting a half-life of 26 min in the incubate. While both 1,2- and 1,3-GDNs were generated from GTN, formation of 1,3-GDN was predominant (GDN ratio, as 1,2/1,3-GDN, = 0.7-0.8). Coincubation with 2 x 10(-5) M concentrations of two GST inhibitors, sulfobromophthalein (SBP) and ethacrynic acid (ECA), decreased the rate of GTN loss. The GTN half-lives in SBP- and ECA-treated incubations were 66 and 84 min, respectively. In addition, the pattern of GDN formation was also altered. The resultant GDN ratios exceeded unity in the presence of these inhibitors, indicating that 1,3-GDN formation was attenuated to a greater extent than that of 1,2-GDN. These data suggest that vascular GTN metabolism in BCA is carried out by cytosolic GST isozymes which possess a preference for C-2 denitration of GTN.