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Biomedical subjects

M Bernstein

Publications and source records attributed to M Bernstein.

At least 91 records · Page 5Linked to original sources
PubMed1997

Effects of iodine-125 brachytherapy on the proliferative capacity and histopathological features of glioblastoma recurring after initial therapy.

OBJECTIVE: To determine the effect of initial therapy (surgery and external beam radiation) on the proliferative capacity of glioblastoma and whether adjunctive high focused doses of radiation therapy can further reduce the proliferative capacity of the tumor. This would provide a rationale for attempting to further control local tumor growth with the different forms of high-dose focused radiation available. METHODS: Patients with glioblastoma were initially treated within a randomized, controlled study with or without iodine-125 (125 I) brachytherapy after initial surgical resection and external beam radiation (50 Gy in 25 fractions). Specimens from 24 consecutive patients later reoperated for "recurrence" were used to determine the effects of 125 I brachytherapy on the histological features and proliferating cell nuclear antigen index of the tumor tissue. RESULTS: 125 I brachytherapy reduced histological features prognostic for tumor progression, i.e., cellularity, pleomorphism, vessel hyperplasia, and degree of mitosis (P < 0.05). The degree of mitosis (marker for the mitotic or "M" phase) and proliferating cell nuclear antigen index (market for the late G1 and S phase) provide complementary data on the cell kinetics of the tumor. Proliferating cell nuclear antigen immunostaining was lower in the 125 I brachytherapy group (34.6 +/- 8.2%, mean +/- standard error) compared with the control nonimplant group (68.2 +/- 3.5%). 125 I brachytherapy produced a dramatic reduction in mitotic figures (mean histological score = 0.0 +/- 0.0). CONCLUSION: Adjunctive treatment of glioblastoma with discrete high doses of radiation therapy delivered by 125 I brachytherapy allows further control of the proliferative capacity of the tumor.

Adolescent↗
PubMed1997

Effect of implant dose/volume and surgical resection on survival in a rat glioma brachytherapy model: implications for brain tumor therapy.

OBJECTIVE: This study sought to investigate the effects of implant dose/volume and surgical resection on survival in a rat glioma brachytherapy model. Two doses were investigated to determine a suitable therapeutic range. METHODS: We performed two experiments. Three treatment groups and one control group of male F-344 rats bearing 9L brain tumors 12 days after tumor inoculation were used in the first experiment. Day 12 tumors were an average of 4 to 6 mm in diameter. Animals treated with brachytherapy received a tumor dose of 80 Gy delivered to a 5.5-mm-radius volume. Total macroscopic tumor removal was achieved by microsurgical techniques. A subsequent experiment compared the survival of tumor-burdened rats treated with an implant dose of 60 Gy delivered to a 5.5-mm-radius volume with a control group. RESULTS: Surgery alone produced an increased life span of 28.6% over control animals treated with sham surgery and dummy seed implants, a statistically significant increase in survival (P = 0.0023, log-rank test). Brachytherapy alone produced the most significant increase in survival over control animals (P = 0.0001, log-rank test; median survival not attained with an implant dose of 80 Gy delivered to a 5.5-mm-radius volume; and P = 0.0001, increased life span 121% with an implant dose of 60 Gy delivered to a 5.5-mm-radius volume). This was not improved by the addition of surgical tumor removal. CONCLUSION: We have demonstrated a relationship between implant dose/volume and survival of tumor-burdened rats in this model that is not improved by the addition of tumor removal. Implications for brain tumor brachytherapy are discussed.

Animals↗
PubMed1997

Multilevel anterior cervical corpectomy and fibular allograft fusion for cervical myelopathy.

This study was conducted to determine the safety and efficacy of multilevel anterior cervical corpectomy and stabilization using fibular allograft in patients with cervical myelopathy. Thirty-six patients underwent this procedure for cervical myelopathy caused by spondylosis (20 patients), ossified posterior longitudinal ligament (four patients), trauma (one patient), or a combination of lesions (11 patients). The mean age (+/- standard deviation) of the patients was 58 +/- 10 years and 30 of the patients were men. The mean duration of symptoms before surgery was 30 +/- 6 months and 11 patients had undergone previous surgery. Prior to surgery, the mean Nurick grade of the myelopathy was 3.1 +/- 1.4. Seventeen patients also had cervicobrachial pain. Four vertebrae were removed in six patients, three in 19, and two in 11 patients. Instrumentation was used in 15 cases. The operative mortality rate was 3% (one patient) and two patients died 2 months postoperatively. Postoperative complications included early graft displacement requiring reoperation (three patients), transient dysphagia (two patients), cerebrospinal fluid leak treated by lumbar drainage (three patients), myocardial infarction (two patients), and late graft fracture (one patient). One patient developed transient worsening of myelopathy and three developed new, temporary radiculopathies. All patients achieved stable bone union and the mean Nurick grade at an average of 31 +/- 20 months (range 0-79 months) postoperatively was 2.4 +/- 1.6 (p < 0.05, t-test). Cervicobrachial pain improved in 10 (59%) of the 17 patients who had preoperative pain and myelopathy improved at least one grade in 17 patients (47%; p < 0.05). Twenty-six surviving patients (72%) were followed for more than 24 months and stable, osseous union occurred in 97%. These results show that extensive, multilevel anterior decompression and stabilization using fibular allograft can be achieved with a perioperative mortality and major morbidity rate of 22% and with significant improvement in pain and myelopathy.

Aged↗
PubMed1997

Clinical and epizootiological study of a leptospirosis outbreak due to Leptospira canicola in a feedlot.

This report describes the epizootiology, clinical presentation, diagnosis and treatment of an outbreak of leptospirosis caused by Leptospira canicola in feedlot calves. The infection appeared to be of high morbidity with a cumulative clinical incidence of 15.6%, cumulative subclinical incidence of 39% and high mortality (8.3%). Clinical disease was diagnosed in 4-8-month-old calves, while subclinical infection occurred in 9-12-month-old calves. Subclinical infection was based on serological evidence only. The zoonotic aspects of the infection are emphasised.

Animal Feed↗
PubMed1997

Pulmonary hemodynamics modify the rat pulmonary artery response to injury. A neointimal model of pulmonary hypertension.

Hemodynamic factors have profound influences on blood vessels. To test the hypothesis that hemodynamic conditions modify the pattern of remodeling in response to injury, monocrotaline (MCT) injury in Sprague-Dawley rats was followed 1 week later by left pneumonectomy to increase blood flow to the right lung. Right pulmonary artery remodeling in these MCT plus pneumonectomy animals was compared with animals receiving MCT or pneumonectomy alone. Neointimal changes developed in more than 90% of all right lung intra-acinar vessels 5 weeks after MCT injury (4 weeks after pneumonectomy). Neointimal lesions did not develop in untreated animals or in animals receiving MCT or pneumonectomy only. Animals with a neointimal pattern of remodeling developed severe right ventricular hypertrophy (RVH) whereas animals with a medial hypertrophy pattern of remodeling (MCT only) developed moderate RVH compared with control animals. Neointimal lesions and RVH were similar whether injury preceded pneumonectomy or vice versa. To exclude the possibility that neointimal lesions resulted from injury plus post-pneumonectomy compensatory lung growth, rather than injury plus increased flow, a left subclavian-pulmonary artery anastomosis was substituted for pneumonectomy. Neointimal lesions and severe RVH developed in these animals but were not seen in animals receiving either MCT or anastomosis only. These studies demonstrate an important role for hemodynamics in determining the pattern of pulmonary vascular remodeling after injury.

Actins↗
PubMed1996

Receptor-mediated calcium signalling in glial cells from mouse corpus callosum slices.

We addressed the question of whether glial cells in intact white matter tracts express neurotransmitter receptors and we used Ca+2 signalling as a probe to detect the receptor activation. Corpus callosum slices from postnatal mice were bulk-loaded with the Ca+2-sensitive fluorescent dye fluo-3, and confocal microscopy was used to measure Ca+2 transients in response to neuroligands. Glial cell bodies were intensely dye-loaded and could be discriminated from the diffuse fluorescence of axons. Subpopulations of glial cells from slices obtained at postnatal days 3 to 7 responded with Ca+2 signals to ATP, glutamate, histamine, GABA, norepinephrine, serotonin, angiotensin II, bradykinin, and substance P. These subpopulations showed a distinct overlap; cells which were responsive to substance P always showed Ca+2 signalling in response to histamine, ATP, GABA and high K+ (membrane depolarization). GABA-responsive cells almost always showed a [Ca+2]i increase after membrane depolarization. In brain slices from postnatal day 11 to 18 animals, the Ca+2 responses were evident for glutamate, ATP, and norepinephrine, while GABA, substance P, serotonin, histamine, or angiotensin II rarely elicited a response. This study demonstrates that white matter glial cells in slices exhibit a large repertoire of neurotransmitter responses linked to Ca+2 signalling and that these receptor systems are differentially distributed on sub-populations of glial cells.

Animals↗
PubMed1996

Relation of breast cancer with passive and active exposure to tobacco smoke.

Studies on passive smoking have consistently shown a tendency toward an increased risk of breast cancer, while studies an active smoking have failed to demonstrate an association. This apparent contradiction may stem from not separating passive smokers from the unexposed when assessing the effect of active smoking. a population based case-control study was conducted in Geneva, Switzerland, between January 1992 and October 1993 to determine the relation of passive and active smoking to breast cancer when the referent unexposed category consisted of women unexposed to active and passive smoke. The 244 patients with breast cancer (cases) were compared with 1.032 women free of breast cancer (controls). The lifetime history of active and passive smoking was recorded year by year, between the age of 10 and the date of the interview. The adjusted odds of breast cancer for ever active smokers, compared with women unexposed to either passive or active smoke, were 2.2 (95% confidence interval (CI) 1.0-4.4) for an average lifetime consumption of 1-9 cigarettes per day, 2.7% (95% CI 1.4-5.4) for 10-19 cigarettes per day, and 4.6 (95% CI 2.2-9.7) for 30 or more cigarettes per day. Among passive smokers, the adjusted odds ratio was 3.2 (95% CI 1.6-6.3) for being exposed for the equivalent of 2 hours per day for 25 years. The odds ratios were adjusted for known or postulated risk factors of breast cancer, including alcohol and saturated fat intake. There was no evidence of strong selection, detection, or recall biases. Active and passive exposure to tobacco smoke may increase the risk of breast cancer. Additional studies are needed to decide whether the association is causal. Further elucidation of this relation would benefit not only the prevention of breast cancer but also the the prevention of other smoking-related diseases in women.

Adult↗
PubMed1996

Chromosome 12-linked autosomal dominant scapuloperoneal muscular dystrophy.

Scapuloperoneal syndromes are characterized by their distribution of muscle weakness and wasting. The reported pattern of inheritance has been variable. Both neurogenic and myopathic forms of autosomally dominantly inherited scapuloperoneal syndrome have been described. It has been suggested that these are variants of other neuromuscular diseases. We examined 44 members from a family with 14 members affected with a scapuloperoneal syndrome. Physiological and histological analysis implied that this condition is predominantly myopathic. Linkage analysis was done to confirm the genetic etiology of the disease in this family and to evaluate the possibility that it is a allelic variant of other neuromuscular diseases. Genetic analysis demonstrated linkage of the disease to chromosome 12, which makes it genetically distinct from other loci known to cause neuromuscular disease. Muscle fibers with hyaline desmin-containing cytoplasmic inclusions in combination with focal myopathic changes may be a disease-specific morphological marker of the disease.

Adult↗
PubMed1996

Laparoscopic colorectal surgery: analysis of 140 cases.

BACKGROUND: This study was performed to prospectively assess the results of our first 140 consecutive patients who underwent laparoscopic or laparoscopic-assisted colorectal operations. METHODS: The parameters studied included the type and length of procedure, intra- and postoperative complications, conversion to open surgery, and length of ileus and hospitalization. RESULTS: 140 laparoscopic and laparoscopic-assisted procedures were performed between May 1991 and January 1995. The mean patient age was 48 (range 12-88) years; there were 78 males and 62 females. Indications for surgery included inflammatory bowel disease in 47, colorectal carcinoma in 19, diverticular disease in 17, polyps in 16, familial polyposis in 7, colonic inertia in 7, fecal incontinence in 11, sigmoidocele in 3, irradiation proctitis in 3, rectal prolapse in 2, intestinal lymphoma in 2, and miscellaneous conditions in 6. The procedures included 38 total abdominal colectomies (TAC) (ileoanal reservoir 28, ileorectal anastomosis 8 and end ileostomy 2); 70 segmental resections of the colon, small bowel, and rectum; 18 diverting stoma creations; 10 reversal of Hartmann's procedures; and 4 other procedures. In 15 cases, the laparoscopic procedure was converted to a laparotomy (11%); 31 patients (22%) sustained 37 complications, which included: enterotomies(7), hemorrhage(10), intraabdominal abscess(4), prolonged ileus(6), wound infection(4), intestinal obstruction(2), anastomotic leak(1), aspiration(1), cardiac arrhythmia(1), and upper intestinal bleeding(1); there was no mortality. The overall complication rate in TAC cases was significantly higher (42%) when compared to that of all other procedures (segmental resection 17%, others 9%), P < 0.05. The mean length of operating time was 4 (range 2.5-6.5) h for TAC, 2.6 (range 1.5-5.5) h for segmental colonic resections, and 1.7 (range 0.7-4) for all other procedures. The length of ileus was 3.5 (range 2-7) days after TAC, 3 (range 2-7) after the segmental resections and 2 (range 1-4) after the other procedures. The mean length of hospital stay was 6.8 (2-40) days (8.4, 6.5, and 6.3 days for the TAC, segmental resections, and other procedures, respectively). CONCLUSION: The feasibility of laparoscopic colorectal surgery has been well established. TAC is associated with a higher complication rate compared to other laparoscopic colorectal procedures.

Adolescent↗
PubMed1996

[Dietary differences between restaurants and home in a representative sample of the adult population residing in Geneva].

Differences in dietary intakes between those who eat at home and those who eat at the restaurant have not been documented previously. In the present study, three registered dietitians interviewed 626 adult residents of Geneva on the telephone about their diet the day before. Interviews were distributed over the seven days of the week. Participation rate was 80%. Results show that men go more often to the restaurant than women, that young people have lunch at the restaurant more often than older people but that age is not related to having dinner at the restaurant. When a resident of Geneva goes to the restaurant to have dinner, he eats and drinks more than those who eat at home, but the relative content of proteins, lipids and carbohydrates of the diet is not different. In conclusion, in Geneva the diet at the restaurant is very similar to the diet at home. This suggest that the meals in a restaurant tend to adapt to the customer's expectations rather then the opposite. The potential implication for public health is that the priority is to inform the customer about what is a healthy diet, the restaurant owner will follow his client's need.

Adult↗
PubMed1996

Tirilazad does not protect rat brain from brachytherapy-induced injury.

BACKGROUND: Acute and chronic brain injury are common sequelae of high-dose focused radiation, as in radiosurgery and brachytherapy. Development of protectors of radiation injury, which would work in brain but not in tumor, would help enhance the therapeutic ratio of focused-radiation therapy. METHODS: Radiation protection by a clinically available 21-aminosteroid, Tirilazad, was studied in a rat brain brachytherapy model, both in tumor and non-tumor bearing animals. For the tumor model, 9L Glioma/SF line cells were implanted stereotactically into the right frontal lobe of F-344 rats and grew to a sphere of 5.0-mm diameter after 12 days. Animals received a standard brachytherapy dose of 80 Gy to a 5.5-mm radius volume administered by a high-activity removable iodine-125 seed. Radiation damage was evaluated 24 hours after removal of the seeds in all animals and again at 3 months in non-tumor-bearing animals, by T1-weighted gadolinium-enhanced and T2-weighted magnetic resonance imaging (MRI) on a 1.5-T unit. Treated animals received Tirilazad 5 mg/kg intravenously 15 minutes prior to implant, 1 hour after implant, every 6 hours for the duration of the implant, and for 24 hours after removal of the seed. Control animals were administered vehicle only. RESULTS: In both non-tumor-bearing and tumor-bearing rats, no difference in the volume of lesions on enhanced T1 or T2 MRI was seen between the Tirilazad-treated and control groups. In the non-tumor-bearing rats, volume of both T1 enhanced and T2 MRI lesions was significantly reduced at 3 months compared to the values at 24 hours. CONCLUSIONS: In the present model, Tirilazad failed to reduce the volume of radiation brain injury from brachytherapy as seen on MRI, studied acutely in tumor-bearing and non-tumor-bearing animals and also at 3 months in non-tumor-bearing rats.

Animals↗
PubMed1996

Neuron-like physiological properties of cells from human oligodendroglial tumors.

One of the most common symptoms of patients with oligodendrogliomas is the high frequency of epileptic seizures. We thus studied the physiological properties of cells in six human oligodendrogliomas and two oligoastrocytomas obtained from surgical material. The majority of tumor cells in living brain slices can generate action potentials as recorded with the patch-clamp technique indicating that this tissue is dominated by electrically excitable cells. In cultures from the same material, the action potential generating cells prevail within the first days and are subsequently replaced by electrically inexcitable cells. From histopathological and immunohistochemical data, the histogenesis of human oligodendroglial tumor is still uncertain. Our physiological study has not settled the debate on the origin of these tumors but revealed important findings with regard to this question. Since action potential generating glial cells have not been described in situ so far their occurrence in oligodendroglial tumors implies that oligodendroglial tumor cells may belong to the neuronal cell lineage.

Adult↗
PubMed1996

Stereotactic management of bacterial brain abscesses.

BACKGROUND: CT and MR guided stereotactic techniques have provided promising results in the management of brain abscesses. We reviewed our results of stereotactic management of brain abscesses in 20 consecutive patients with 28 abscesses from 1986 to 1993. METHODS: 13 abscesses were in the cerebral hemispheres, 12 in the cerebellum, 2 in the pons and 1 in the thalamus. The bacterial organism was isolated in 12 of the 20 cases. All patients, except one who had a tuberculous abscess, were on antibiotics for less than 7 weeks. RESULTS: Although there were 3 patients in coma before surgery, the mortality rate was zero and 17 patients had an excellent recovery with 3 patients having a persistent mild neurologic disability. Stereotactic aspiration of the largest lesion in the patients with multiple brain abscesses combined with intravenous antibiotic therapy was sufficient for the resolution of all lesions. Two of our patients treated with antibiotics alone showed abscess progression with neurologic worsening. CONCLUSION: Stereotactic aspiration is safe, accurate, and when combined with the appropriate antibiotics, should be considered the procedure of choice in the management of brain abscesses.

Adult↗
PubMed1996

Current treatment of cerebral metastasis.

Brain metastasis from systemic cancer remains a significant source of morbidity and mortality. Current treatment modalities include surgery, whole brain radiation, radiosurgery, brachytherapy, chemotherapy, and other experimental methods such as hyperthermia, hormonal therapy, and the use of biological modifiers. In this article we review and evaluate recent developments in these treatment modalities for the management of cerebral metastasis.

Brachytherapy↗
PubMed1996

The association between tumour necrosis factor-alpha, interleukin-6 and microbiological findings in the synovial fluid of aborted and neonatal calves.

Tumour necrosis factor-alpha (TNF alpha) and interleukin-6 (IL-6) were detected in the intra-carpal synovial fluids collected from aborted and recently dead young calves. Five out of seven TNF-alpha positive joint fluids were bacteriologically positive and two were sterile. Only one out of 20 TNF-alpha negative joint aspirates was infected (P = 0.0014). Sixteen of the synovial fluid samples were examined for the presence of IL-6. In 12 samples IL-6 was detected, six of which were bacteriologically contaminated. Four out of the 16 samples were IL-6 negative. These findings indicated the possible association between TNF-alpha and the intra-articular inflammatory processes in young calves, which in the present study were either found in combination with or without IL-6.

Abortion, Veterinary↗
PubMed1996

Passive smoking, active smoking, and education: their relationship to weight history in women in Geneva.

OBJECTIVES: This study was undertaken to determine the relationship of education and tobacco smoke to lifetime weight history in women. METHODS: Information on passive smoking, active smoking, and weight history was collected from 928 women aged 29 to 74 years selected from the general population of Geneva, Switzerland. Multivariate analysis of variance was performed for weight, weight at age 20, and weight changes since age 20. RESULTS: Education was inversely related to weight at age 20, current weight, and weight gain since age 20. The least educated group had a current weight of 4 kg more than the most educated group. Differences across smoking categories were small: passive smokers had the highest current weight (63.4 kg) and former active smokers had the lowest (60.4 kg). Weight gain since age 20 tended to be smaller in former and current active smokers (5.5 to 7.2 kg) than in passive smokers (8.3 to 10.4 kg) and those never exposed (9.1 kg). CONCLUSIONS: In this sample, education was an important predictor of women's current weight and weight history. Passive and active smoking had little long-term effect on weight.

Adult↗