Search PubMed⌕ Search

Biomedical subjects

Y Barak

Publications and source records attributed to Y Barak.

At least 163 records · Page 9Linked to original sources

Withdrawal emergent syndrome in an infant associated with maternal haloperidol therapy.

Withdrawal emergent syndrome (WES) is a subtype of tardive dyskinesia that has been reported in children who were taken off antipsychotic therapy. We present the first case of WES in an infant born to a mother taking haloperidol during her pregnancy. The infant developed repeated tongue thrust, abnormal hand posturing, and tremor of all extremities. Most symptoms resolved within several days, but tongue thrust continued until 6 months of age.

Adult↗

Effect of experimental cardioplegia methods on normal and hypertrophied rat hearts.

The purpose of this study was to evaluate whether the addition of verapamil hydrochloride to oxygenated glucose-rich cardioplegic solution would improve myocardial preservation. The Langendorff preparation of the isolated rat heart was used. Groups of normal (WKY) and hypertrophied (SHR) hearts were treated by five different cardioplegic methods and subjected to 90 or 30 minutes of ischemia at 28 degrees to 29 degrees C and reperfusion at 37 degrees C. The following cardioplegic solutions were used: Group A, cold (16 degrees C) Krebs-Henseleit (KH) glucose free only; Group B, KH with KCL (30 mEq/L) (16 degrees C); Group C, same as B with verapamil (10 microM); Group D, perfusion with oxygenated KH solution containing KCL (30 mEq/L) for 15 minutes prior to ischemia; and Group E, same as D with verapamil (10 microM). Recovery of contraction amplitude, ischemic contracture, coronary perfusate volume, the amount of creatine kinase in the coronary perfusate, heart rate, time of revival, O2 consumption, and ischemic contracture were measured. After 30 minutes of ischemia, we did not find any significant difference among the combinations tested with respect to contraction amplitude recovery. The hearts recovered fully. After 90 minutes of ischemia, we found that the best-protected groups in the normal hearts were Groups D and E. In the hypertrophied hearts, the addition of verapamil to the enhancement solution was harmful. The use of enhancement solution without verapamil prior to ischemia provided the best myocardial protection in the hypertrophied hearts.

Animals↗

The performance of primary and secondary unexplained infertility in an in vitro fertilization-embryo transfer program.

The term "unexplained infertility" is applied to a couple in whom after an elaborate workup no apparent reason for infertility is found. Between August 1985 and May 1987, 435 patients underwent 720 treatment cycles in an in vitro fertilization-embryo transfer (IVF-ET) unit. Eighty-three of the patients had unexplained infertility as their indication for IVF-ET. Fifty-two (group A) had primary unexplained infertility and 31 (group B) had secondary unexplained infertility. Group A underwent 87 and group B underwent 50 treatment cycles. Forty-six ET were performed in group A and 34 in group B. Clinical pregnancies were achieved in 20 patients of group A (11.5% per treatment cycle) and 13 of group B (26.0%), for a combined rate of 16.8% per cycle. Patients with tubal infertility treated in the program had a pregnancy rate of 18.8% per treatment cycle. The performance of the secondary unexplained infertility group is significantly better than that of the primary unexplained infertility group. However, the overall results with patients with unexplained infertility are similar to those patients treated for tubal infertility.

Embryo Transfer↗

The development of an efficient ambulatory in vitro fertilization (IVF) and embryo transfer (ET) program using ultrasonically guided oocyte retrieval.

Until recently most of the current in vitro fertilization and embryo transfer (IVF-ET) programs used laparoscopy for oocyte retrieval and included hospitalization in the treatment. The establishment of a successful ambulatory IVF program that uses ultrasonically guided oocyte aspiration, is described. Between August 1985 and February 1987, 384 percutaneous transvesical ultrasonically and transvaginally guided follicle aspirations were performed on 414 patients, following ovarian stimulation with hMG and hCG. Ninety two clinical pregnancies were confirmed by ultrasound. The clinical pregnancy rate was 26.8% when based on the number of embryo transfers. There were 16 multiple pregnancies (17.4%), 18 miscarriages (19.5%), and two tubal pregnancies (2.1%). The most important factors contributing toward the success of this program were rigid adherence to clinical and laboratory protocols, and the maintenance of a strict quality control. The ambulatory management was very well accepted by the patients, who during the entire period of ovarian stimulation had minimal disruption of their routine activities.

Adult↗

Bone marrow transplantation for constitutional pure red cell aplasia.

Constitutional pure red cell aplasia (CPRCA) is a syndrome of failed erythropoiesis usually diagnosed within the first year of life. Four patients with CPRCA received transplants with marrow from their HLA-identical, mixed lymphocyte culture-nonreactive siblings. All patients were resistant to corticosteroid therapy and were dependent on regular red cell transfusions for at least 5 years. Three patients were conditioned with procarbazine, antithymocyte globulin, cyclophosphamide, and busulfan, and one was conditioned with antithymocyte serum, cyclophosphamide, and busulfan. Three patients promptly had successful engraftments with establishment of donor hematopoiesis. One patient initially rejected his graft but received a successful retransplant. All patients are currently alive with Karnofsky performance scores of 100 and normal erythropoiesis of donor origin. Despite a history of multiple transfusions, bone marrow transplantation is a potentially curative therapy for patients with CPRCA.

Adolescent↗

Right and left colon carcinoma: a retrospective comparative study.

We studied 347 patients with primary colorectal carcinoma treated by surgery during 1973-1983: 64 (18.2%) with right colon carcinoma, 158 (45.7%) with left colon carcinoma, 14 (4.2%) with transverse colon carcinoma, and 110 (31.9%) with rectal carcinoma. We compared the right-sided carcinoma (RSC) and left-sided carcinoma (LSC) groups. Obstruction was found in 17.2% of RSC compared with 20.3% LSC patients (P greater than 0.05). Advanced disease (Dukes stages C and D) was found in 34.4% on the right and 47.8% on the left side (P = 0.01). Crude 5-year survival rate, by life table method, was 71% on the right and 66% on the left side (P greater than 0.05); this difference became significant (P = 0.03) when Dukes stage B patients were compared. We conclude that patients with RSC are not diagnosed, as is commonly believed, at advanced stages of the disease. We found that the 5-year survival rate of RSC patients was the same or, occasionally, better than that of LSC patients.

Actuarial Analysis↗

Estrone-3-glucuronide chemiluminescence immunoassay: an alternative method for monitoring induction of ovulation with human menopausal gonadotropin in an in vitro fertilization program.

A simple, rapid, and sensitive solid-phase immunoassay procedure for the determination of estrone-3-glucuronide (E1-3-G), which uses chemiluminescence as the end point in unextracted morning urine, is described. Thirty-one patients undergoing induction of ovulation in an in vitro fertilization (IVF) unit participated in the study. From day 3 of the menstrual cycle until the day of hCG administration, morning blood samples and morning urine specimens were collected for the determination of serum 17 beta-estradiol (E2) and urine E1-3-G, respectively. A good correlation was noted between E2 measured by radioimmunoassay (RIA) and the E1-3-G measured by chemiluminescence immunoassay (CIA), from day 5 up to the day of hCG administration (0.6 less than r less than 0.85, P less than 0.001). It is evident from this study that the CIA measurement of E1-3-G in morning urine is an accurate and rapid (2.5 hours) method and is convenient for monitoring induction of ovulation with human menopausal gonadotropins.

Adult↗

Chediak-Higashi syndrome.

The use of cytochemical, electron microscopic, immunofluorescent, and tissue culture techniques has led to important advances in our understanding of the mechanisms underlying the pathogenesis of the Chediak-Higashi syndrome (CHS). This rare and fatal autosomal recessive disorder is clinically characterized by partial albinism, frequent pyogenic infections, and an accelerated lymphohistiocytic phase. The pathological hallmark of CHS is the presence in all white blood cells of massive lysosomal inclusions, which are formed through a combined process of fusion, cytoplasmic injury, and phagocytosis. The abnormal inclusions exhibit both azurophilic and specific granular markers, and are probably responsible for most of the impaired leukocyte and other cell functions in CHS patients. In addition, a selective profound natural killer (NK) cell function and platelet storage pool deficiencies have been described in these patients. Impaired microtubule assembly and functions, mediated by abnormal intracellular cyclic nucleotide levels, which could be corrected by treatment with ascorbic acid, were suggested to be the pathophysiological basis for CHS abnormalities. However, some recent studies have questioned this cytoskeletal model, which is suggested to be rather a secondary manifestation of CHS.

Antineoplastic Agents↗

Granulopoiesis in aged people: inverse correlation between bone marrow cellularity and myeloid progenitor cell numbers.

Results of a study on bone marrow (BM) cytology and cellularity, BM granulocytic-macrophage colony formation (GM-CFU-C), peripheral blood (PB) colony stimulating factor (CSF) and serum lysozyme activity in 20 elderly people aged from 64 to 89 are presented. Besides slight iron deficiency anemia, no hematological abnormality was detected. No change in PB and BM differential counts was found as compared to those obtained for normal adults. The BM cellularity and colony incidence were assessed using aliquots of the same specimen. GM-CFU-C frequency ranged from 15 to 156 (average 67.5) per 2 X 10(5) BM cells seeded. The largest number of colonies was observed in hypocellular BM samples (p less than 0.002). The level of serum lysozyme activity for the entire group was significantly higher than that obtained in healthy persons up to the age of 60 (p less than 0.001). The overall results support the notion that in old age, increased proliferation of committed granulopoietic stem cells in hypoplastic areas of the BM, assure normal numbers of mature blood cells in the periphery.

Aged↗

Muscarinic binding sites in newborn brain from intrauterine growth-retarded rabbits.

Intrauterine growth retardation (IUGR) was induced in rabbits by means of vascular ligation in utero 4-6 days prior to birth. The vascular-restricted living newborns and controls from the unligated uterine horns were killed at birth and the level of the muscarinic cholinergic receptors in cerebral and cerebellar homogenates measured using the potent antagonist 3H-QNB. No significant difference in the binding sites of the cerebellum and the cerebral cortex was found between restricted and control animals. It is speculated that the ineffectiveness of the vascular insult to affect specifically muscarinic binding sites could partially be explained by the specificity of the receptors and the timing of the ischemic insult in relation to the stage of the developing brain. Other cholinergic markers should also be assessed.

Animals↗

Combined effect of glucose and verapamil in experimental cardioplegia.

In this study, we determined whether pre-ischemic enhancement of the ATP level and the addition of verapamil (a calcium blocker) to the cardioplegic solution could improve myocardial protection during cardiac arrest. Using the Langendorff preparation of the isolated rat heart plus different cardioplegic solutions, five groups of normal rat hearts and five groups of hypertrophied rat hearts were subjected to 90-minute ischemic periods at 28 degrees +/- 1 and reperfusion of 30 minutes at 37 degrees C. Group A received no cardioplegic solution; Group B received KCl, 30 mEq/L; Group C received type B perfusion with verapamil; and Group D received 15 minutes of pre-ischemic oxygenated enhancement perfusion containing KCl, 30 mEq/L, and glucose as substrate at 37 degrees C. Group E received the same perfusion as Group D, with the addition of verapamil to the enhancement perfusion. Light and E/M microscopy was performed on representative samples of left ventricular muscle. We found that pre-ischemic enhancement with KCl, glucose, and verapamil was only protective in the normal hearts after 90 minutes of ischemia. In hypertrophied hearts, the addition of verapamil to the enhancement solution was harmful. The use of pre-ischemic enhancement solution without verapamil provided the best myocardial protection after 90 minutes of ischemia in the hypertrophied hearts.

Journal Article↗

Chediak-Higashi syndrome. Expression of the cytoplasmic defect by in vitro cultures of bone marrow progenitors.

Studies on proliferation and differentiation of granulocyte-monocyte progenitor cells in Chediak-Higashi syndrome (CHS) were done on a 1-month-old patient, using the soft-agar bone marrow culture technique. The number of granulocyte-macrophage colony-forming cells (GM-CFC) was markedly increased, but with a normal distribution into granulocyte, macrophage, or mixed colonies. Morphologic, cytochemical, and ultrastructural studies showed that 70% of the colonies consisted of cells with giant lysosomes typical of CHS, and in the remaining 30% abnormal cells were not detected. The supply of granulocyte-macrophage colony-stimulating factor (GM-CSF) by the patient's peripheral blood leukocytes was markedly decreased. Inhibition of normal in vitro granulopoiesis by the patient's lymphocytes or serum was not demonstrated. It appears that granulocyte progenitors in CHS proliferate normally, or even in excess, probably in response to intramedullary destruction of granulocytes. The majority of the progenitors are intrinsically defective and give rise to colonies that contain the abnormality. In others the defects are unidentifiable, probably due to the immaturity of the specific fusion process of the cytoplasmic granules. The abnormal leukocytes in CHS are also defective in their capacity to provide GM-CSF, and this may account in part to the overt neutropenia. These studies demonstrate that the basic cytoplasmic abnormalities of the granulocytes and monocytes in CHS are embedded in the granulocytic-monocytic committed stem cell.

Bone Marrow↗

Pseudotumor cerebri in a boy with 11-beta-hydroxylase deficiency--a possible relation to rapid steroid withdrawal.

A boy who was known to suffer from adrenogenital syndrome due to 11-beta-hydroxylase deficiency was treated with appropriate steroid replacement, which fully compensated for the deficiency. An intercurrent febrile illness with anorexia and vomiting necessitated an abrupt discontinuation of steroids. He presented with classic signs of pseudotumor cerebri 3 days following steroid withdrawal. Our studies imply that a combination of steroid withdrawal and dehydration with increased sodium urinary excretion, caused rapid fluid shifts within the brain, resulting in intracranial hypertension. At present, when a considerable number of children are on long-term steroids for various reasons, pseudotumor cerebri should be considered in the list of complications during abrupt steroid withdrawal.

Adrenal Hyperplasia, Congenital↗