Biomedical subjects

Y Barak

Publications and source records attributed to Y Barak.

At least 55 records · Page 3Linked to original sources

PubMed2000

Working with mentally ill homeless persons: should we respect their quest for anonymity?

In recent years, the homeless population has received much attention as authorities attempt to comprehend this phenomenon and offer solutions. When striving to establish a relationship with the homeless person, many problems arise. We encounter this dilemma when respecting the right of the mentally ill to dwell neglected in the streets and simultaneously observe their inability to comprehend provisions such as housing, shelter, medical and mental care which contribute to their human dignity. The polarities of autonomy versus involuntary treatment are highlighted when treating the homeless population.

Adult↗

PubMed2000

Improved insulin-sensitivity in mice heterozygous for PPAR-gamma deficiency.

The thiazolidinedione class of insulin-sensitizing, antidiabetic drugs interacts with peroxisome proliferator-activated receptor gamma (PPAR-gamma). To gain insight into the role of this nuclear receptor in insulin resistance and diabetes, we conducted metabolic studies in the PPAR-gamma gene knockout mouse model. Because homozygous PPAR-gamma-null mice die in development, we studied glucose metabolism in mice heterozygous for the mutation (PPAR-gamma(+/-) mice). We identified no statistically significant differences in body weight, basal glucose, insulin, or FFA levels between the wild-type (WT) and PPAR-gamma(+/-) groups. Nor was there a difference in glucose excursion between the groups of mice during oral glucose tolerance test, but insulin concentrations of the WT group were greater than those of the PPAR-gamma(+/-) group, and insulin-induced increase in glucose disposal rate was significantly increased in PPAR-gamma(+/-) mice. Likewise, the insulin-induced suppression of hepatic glucose production was significantly greater in the PPAR-gamma(+/-) mice than in the WT mice. Taken together, these results indicate that - counterintuitively - although pharmacological activation of PPAR-gamma improves insulin sensitivity, a similar effect is obtained by genetically reducing the expression levels of the receptor.

Animals↗

PubMed2000

Melatonin improves sleep quality of patients with chronic schizophrenia.

BACKGROUND: Accumulating evidence indicates decreased melatonin levels in patients with schizophrenia. Insomnia, mainly difficulty in falling asleep at night, is commonly reported in this population. Association of insomnia with low or abnormal melatonin rhythms has been repeatedly documented. Melatonin is an endogenous sleep promoter in humans. We hypothesized that insomnia in patients with schizophrenia may be partially due to diminished melatonin output. In this study, we measured melatonin output in patients with chronic schizophrenia and assessed the effects of melatonin replacement on their sleep quality. METHOD: In a randomized, double-blind, cross-over, clinically based trial, 19 patients with DSM-IV schizophrenia who were treated with the normal treatment regimen were given melatonin (2 mg, controlled release) or placebo for 2 treatment periods of 3 weeks each with 1 week washout between treatment periods (7 weeks total). For measuring endogenous melatonin production, urine was collected from each patient every 3 hours between 9:00 p.m. and 9:00 a.m. Actigraphy was performed for 3 consecutive nights at the end of each period. Activity- and rest-derived sleep parameters were compared for the whole population with treatment arm as the intervening variable. A separate analysis was performed for patients subgrouped into high versus low sleep efficiency. RESULTS: All patients had low melatonin output. Melatonin replacement significantly improved rest-derived sleep efficiency compared with placebo (83.5% vs. 78.2%, p = .038) in this population. Improvement of sleep efficiency was significantly greater (p < .0014) in low-efficiency (80% vs. 67%) than high-efficiency sleepers (88% vs. 90%). In addition, during melatonin therapy, tendencies toward shortened sleep latency (by 40 minutes, p < .056) and increased sleep duration (by 45 minutes, p < .078) were observed in low- but not high-efficiency sleepers. CONCLUSION: Melatonin improves sleep efficiency in patients with schizophrenia whose sleep quality is low.

Adult↗

PubMed2000

Is melatonin treatment effective for tardive dyskinesia?

BACKGROUND: Tardive dyskinesia is a severe and disabling side effect of conventional antipsychotic treatment, with incidence rates reaching a high of 50% in chronically institutionalized populations. On the basis of recent studies showing some benefit of antioxidants, we evaluated the effect of melatonin, the most potent naturally occurring antioxidant, on tardive dyskinesia in patients with chronic schizophrenia. METHOD: Nineteen patients (8 men, 11 women), aged a mean +/- SD 74.0+/-9.5 years with chronic DSM-IV schizophrenia of 31.3+/-7.0 years' duration, were randomly assigned in a double-blind, placebo-controlled, crossover trial to receive slow-release melatonin, 2 mg/day, or placebo for 4 weeks. After a 2-week washout period, the patients were switched to the other treatment arm for an additional 4 weeks. The Abnormal Involuntary Movement Scale (AIMS) was administered at baseline, 4 weeks, 6 weeks, and 10 weeks. Regular administration of antipsychotic and other medications was kept unchanged throughout the study. RESULTS: Mean AIMS scores did not change significantly from baseline in either treatment arm. All patients completed the study, and there were no side effects or adverse events. CONCLUSION: Supraphysiologic doses of melatonin do not positively affect tardive dyskinesia. Considering that melatonin is a safe drug, further studies are needed of higher doses and in patients with shorter disease duration before its use in the treatment of tardive dyskinesia is ruled out.

Aged↗

PubMed2000

The influence of aprotinin on myocardial function after liver ischemia-reperfusion.

BACKGROUND: The beneficial effect of aprotinin, a naturally occurring protease inhibitor, on preservation of organs such as the liver, kidney and lung has been documented. OBJECTIVE: To explore the effects of hepatic ischemia and reperfusion on both liver and myocardial function, using a dual isolated perfused organ model with and without aprotinin. METHODS: Isolated rat livers were stabilized for 30 minutes with oxygenated modified Krebs-Henseleit solution at 37 degrees C. Livers were then perfused continuously with KH or KH + aprotinin 10(6) KIU/L for an additional 135 min. Livers of two other groups were made globally ischemic for 120 min, then perfused for 15 min with KH or with KH + aprotinin. Isolated hearts (Langendorff preparation) were stabilized for 30 min and then reperfused with KH or KH + aprotinin exiting the liver for 15 min. The liver's circuit was disconnected, and hearts were re-circulated with the accumulated liver + heart effluent for an additional 50 min. RESULTS: In the ischemia and ischemia + aprotinin groups, portal vein pressure (1 and 15 min reperfusion) was 331 +/- 99% and 339 +/- 61% vs. 308 +/- 81% and 193 +/- 35% of baseline, respectively (P < 0.03 vs. ischemia). There were no other differences in the enzyme leakage between aprotinin-treated or untreated ischemic livers. Left ventricular pressure was stable in the controls. However, LV pressure in groups perfused with ischemic liver effluent declined within 65 min reperfusion, whether aprotinin treated or not (84 +/- 8% and 73 +/- 5% of baseline, respectively, P < 0.004 only for ischemia vs. control). CONCLUSION: When aprotinin was used, LV pressure was inclined to be higher while liver portal vein pressure was lower, thus providing protection against liver and heart reperfusion injury.

Animals↗

PubMed2000

Guardianship for the severely mentally ill.

The process of appointing a guardian in the mental health field is a complex and important one. The guardian's duty is to protect a patient who is incompetent in making his own decisions. The guardian's role can be to correct past mistakes made by the patient (i.e. loss of property), manage the patient's present affairs and prevent future undesirable consequences. Characteristics of patients who are in need of guardianship have not previously been studied in Israel. We examined the characteristics of 60 hospitalized patients for whom a guardian was appointed, comparing them with another group of patients. Variables relating to disease severity such as diagnosis, duration of illness and employment status contrasted the groups. We may tentatively conclude that patients in need of legal guardianship are more severely ill than other mentally ill.

Adult↗

PubMed1999

Low CSF soluble interleukin 2 receptor levels in acute depression. Short communication.

Thirteen patients with DSM-III-R diagnosis of either major depression or bipolar I depression participated in the study. The control group consisted of 10 subjects evaluated for headache or suspected meningitis, none of whom were found to suffer from any organic disease. CSF was withdrawn from all subjects for the measurement of soluble interleukin 2 receptor (sIL-2R). CSF sIL-2R levels were found to be lower in patients as compared to controls (df = 1, 20; F = 84; p<0.000001).

Adult↗

PubMed1999

Fluoxetine treatment for weight reduction in steroid-induced obesity: a pilot study in myasthenia gravis patients.

To evaluate the weight reducing effect of fluoxetine on steroid-induced obesity, we conducted an open, clinical intervention study of 20-40 mg/day fluoxetine, 24 weeks duration. Thirteen myasthenia gravis, overweight, long-term steroid-treated patients [age: 31-59, body mass index (BMI): 29-54 kg/m2] were included. Measurements of weight, BMI, and routine laboratory tests, were undertaken at baseline, 12 and 24 weeks. Muscle strength and fatigue parameters were assessed at 4 week intervals. Fluoxetine induced mean weight loss of 7.7+/-2.6 kg and 10.3+/-2.9 kg over a period of 12 and 24 weeks respectively, (P<0.05). Mean BMI decreased from 35.8 to 32.2 kg/m2 over the study period. No significant side effects were noted. We conclude that patients suffering from steroid-induced obesity respond to fluoxetine treatment of overweight by significant weight loss.

Adult↗

PubMed1999

PPAR gamma is required for placental, cardiac, and adipose tissue development.

The nuclear hormone receptor PPAR gamma promotes adipogenesis and macrophage differentiation and is a primary pharmacological target in the treatment of type II diabetes. Here, we show that PPAR gamma gene knockout results in two independent lethal phases. Initially, PPAR gamma deficiency interferes with terminal differentiation of the trophoblast and placental vascularization, leading to severe myocardial thinning and death by E10.0. Supplementing PPAR gamma null embryos with wild-type placentas via aggregation with tetraploid embryos corrects the cardiac defect, implicating a previously unrecognized dependence of the developing heart on a functional placenta. A tetraploid-rescued mutant surviving to term exhibited another lethal combination of pathologies, including lipodystrophy and multiple hemorrhages. These findings both confirm and expand the current known spectrum of physiological functions regulated by PPAR gamma.

Adipose Tissue↗

PubMed1999

Outcome of psychogeriatric intervention in an old-age home: a 3 years follow-up study.

Psychogeriatrics and especially psychiatric services in nursing and old-age homes are sorely lacking in research. Four years ago we developed and implemented a model for service delivery for old-age homes within our hospitals' catchment area. In the first year of operation 48 of 373 residents (13%) were evaluated and treated by a psychogeriatrician. The aim of the present study was to evaluate outcome of these patients three years later. All patients and medical records were re-assessed. During the three-year period 16/48 subjects (33.3%) passed away; of these half were previously diagnosed as suffering from a major depressive episode. None of the subjects who died had attempted suicide. Following a preliminary diagnosis of affective spectrum disorder, 4/48 patients (8.3%) were re-diagnosed at follow up as suffering from dementia. Full or partial remission of the original symptomatology was achieved in 18/32 surviving subjects (50.7%); mostly depressed or anxious patients. We conclude that although mortality rate among elderly psychiatric patients is high persistent interventions lead to successful remission in the majority of patients.

Aged↗

PubMed1999

Autistic subjects with comorbid epilepsy: a possible association with viral infections.

This study evaluates the comorbidity of epilepsy as a variable supporting a viral hypothesis in Autism. Data covering a 30-year period (1960-1989), including general population live births, autistic births, and incidence of viral encephalitis and viral meningitis, were collected for Israel. 290 autistic births were evaluated. The annual birth pattern of subjects with comorbid epilepsy fit the seasonality of viral meningitis. These findings support the role of viral C.N.S. infections in the causality of this disorder.

Adolescent↗

PubMed1999

hKCa3/KCNN3 potassium channel gene: association of longer CAG repeats with schizophrenia in Israeli Ashkenazi Jews, expression in human tissues and localization to chromosome 1q21.

We demonstrate a significant association between longer CAG repeats in the hKCa3/KCNN3 calcium-activated potassium channel gene and schizophrenia in Israeli Ashkenazi Jews. We genotyped alleles from 84 Israeli Jewish patients with schizophrenia and from 102 matched controls. The overall allele frequency distribution is significantly different in patients vs controls (P = 0.00017, Wilcoxon Rank Sum test), with patients showing greater lengths of the CAG repeat. Northern blots reveal substantial levels of approximately 9 kb and approximately 13 kb hKCa3/KCNN3transcripts in brain, striated muscle, spleen and lymph nodes. Within the brain, hKCa3/KCNN3transcripts are most abundantly expressed in the substantia nigra, lesser amounts are detected in the basal ganglia, amygdala, hippocampus and subthalamic nuclei, while little is seen in the cerebral cortex, cerebellum and thalamus. In situ hybridization reveals abundant hKCa3/KCNN3 message localized within the substantia nigra and ventral tegmental area, and along the distributions of dopaminergic neurons from these regions into the nigrostriatal and mesolimbic pathways. FISH analysis shows that hKCa3/KCNN3 is located on chromosome 1q21.

Base Sequence↗

PubMed1999

Relationship between human sperm lipid peroxidation, comprehensive quality parameters and IVF outcome.

The membranes of human spermatozoa contain an extremely high concentration of polyunsaturated fatty acids and are therefore susceptible to lipid peroxidation damage. The aim of this study was to retrospectively determine the association between the lipid peroxidation levels of washed spermatozoa, as indicated by thiobarbituric-acid-reactive substance concentration, and: (a) semen quality evaluated by basic routine, biochemical, cytological and quantitative ultramorphological analyses; (b) IVF fertilization rate. Semen samples from 45 male partners of couples who had been referred for IVF treatment due to a female infertility factor were evaluated for quality as well as for thiobarbituric-acid-reactive substance concentrations. The latter were found to have a negative correlation with total sperm count, semen volume, zinc/fructose ratio, and the integrity of sperm acrosome and axonema. It was suggested that lipid peroxidation has a deleterious effect on the ultramorphological status of the sperm cells and, thereby, on the male fertilization potential. The content of the seminal fluid, about 30% of which is produced by the prostate, may protect spermatozoa from this destructive process. A negative correlation was also found between thiobarbituric-acid-reactive substance concentrations and IVF fertilization rate. When the patients were subdivided into fertilizing (fertilization rate > 0%) and nonfertilizing (fertilization rate = 0%) subgroups (n = 33 and n = 12, respectively), the former exhibited significantly lower thiobarbituric-acid-reactive substance concentrations than the latter. A new IVF fertilization index based on the lipid peroxidation level was established. This index had a predictive power of 93% (94% sensitivity and 92% specificity). The clinical value of this index should be further verified.

Female↗

PubMed1999

Cerebrospinal cytokine levels in patients with acute depression.

There is increasing evidence for an association between the alteration of cytokine concentrations in blood and the pathophysiology of depressive disorders. Studies in humans have not investigated CSF cytokine concentrations and their relationship to depressive disorders. This study reports on the association of the CSF concentration of proinflammatory cytokines, IL-1beta, IL-6 and TNFalpha, and major depressive disorders. CSF samples were obtained from 13 hospitalized patients with acute unmedicated severe depression and were compared with 10 control subjects. Compared to the control group, the depressed patient group had higher CSF concentrations of IL-1beta, lower IL-6 and no change in TNFalpha. A positive correlation was found between serum IL-1beta and the severity of depression. These results indicate a unique profile for CSF proinflammatory cytokines in acute depression. These findings merit further investigation and if replicated may possibly offer immunological treatment options for depression.

Acute Disease↗

PubMed1999

Moclobemide treatment in multiple sclerosis patients with comorbid depression: an open-label safety trial.

Depression is common in multiple sclerosis (MS) patients, but tricyclic compounds are not well tolerated and newer antidepressants have not been studied. Effects of 150-400 mg/day of moclobemide, a reversible monoamine oxidase A inhibitor, were studied in a 3-month open design in 10 MS patient with DSM-IV-diagnosed depression. Nine patients reached complete remission. No adverse effects were noted. Four patients reported side effects including nausea and insomnia. The authors conclude that moclobemide is a well tolerated and efficient treatment for depression comorbid with MS.

Adult↗

PubMed1998

Antidepressant-associated mania: a study of anxiety disorders patients.

Antidepressants are related to the emergence of manic and hypomanic episodes in mood disorder patients. This study examined whether antidepressant-associated manic states are also present in anxiety disorder patients, so that this phenomenon may be defined as a side-effect. A total of 167 consecutive patients at a specialized outpatient clinic, suffering from anxiety disorders and treated by antidepressants, were assessed in a blind, retrospective chart review. Five patients (2.99%) were identified as having suffered an episode of antidepressant-associated mania within 3 months of initiation of treatment. All were females and all had an axis II diagnosis of a cluster B personality disorder. Antidepressant-associated mania appears to be related to risk factors such as personality disorder, even in non-mood disorder patients, tentatively suggesting that it is not simply an adverse event but rather a reflection of an underlying psychopathology.

Adult↗

PubMed1998

Pregnancy and birth after transfer of embryos that developed from single-nucleated zygotes obtained by injection of round spermatids into oocytes.

OBJECTIVE: To use injection of spermatids into oocytes as a mode of infertility treatment in cases in which spermatozoa are not available. DESIGN: Prospective clinical evaluation and case report. SETTING: In Vitro Fertilization Unit, Herzliya Medical Centers, Herzliya-on-Sea, Israel. PATIENT(S): Thirteen couples with male factor infertility in which the male partner lacked spermatozoa in the ejaculate or testicular biopsy samples. INTERVENTION(S): Round spermatid injection and elongated spermatid injection into oocytes. MAIN OUTCOME MEASURE(S): Evaluation of the rate of two-pronucleated and single-nucleated zygote development. RESULT(S): The rate of two-pronucleated zygote development after round spermatid injection and elongated spermatid injection was relatively low (27% and 36%, respectively). Single-nucleated zygotes develop more frequently after round spermatid injection and elongated spermatid injection (35% and 17%, respectively) than after intracytoplasmic sperm injection with mature spermatozoa. A normal pregnancy and childbirth resulted from the transfer of 4 cleaving embryos, each of which developed from a single-nucleated zygote in a round spermatid injection treatment cycle with ejaculated spermatids. CONCLUSION(S): Embryos derived from single-nucleated zygotes after spermatid conception can be viable and give rise to an ongoing clinical pregnancy and childbirth.

Adult↗

PubMed1998

Juvenile multiple sclerosis: clinical features and prognostic characteristics.

In a retrospective study we analyzed clinical features and their prognostic significance in 72 patients with onset of multiple sclerosis by the age of 21 years. In juvenile multiple sclerosis disease progression does not depend on age of onset, severity of neurologic involvement, or polysymptomatic or monosymptomatic involvement at presentation.

Adolescent↗