Biomedical subjects
Publications and source records attributed to H Cohen.
This experiment investigated the effect of sex differences in categorization of tactile stimuli. 9 men and 9 women rated the perceived similarity between pairs of stimuli varying in texture and shape. The magnitudes of sex-related differences, using omega 2 and d, were relatively large and indicated that men had better categorical abilities in processing haptic information.
Bone marrow samples from normal adults and children with nonhematologic malignancies not involving the marrow, acute lymphoblastic leukemia (ALL) in continued remission, and immune cytopenias were studied by two-color immunofluorescence (IF) and flow cytometry to characterize common acute lymphoblastic leukemia antigen (CALLA)-positive marrow lymphoid cells. Marrow was separated by Ficoll/Hypaque centrifugation followed by passage over a monoclonal antibody affinity column to remove myeloid cells prior to IF staining. A higher proportion of CALLA-positive cells was found in the pediatric marrows (mean, 33.7% +/- 6.3% SEM) than in the adult marrows (mean, 4.5% +/- 1.6% SEM). Two subpopulations of CALLA-positive cells identified by cell sorting to be of lymphoid morphology were found in both adult and pediatric marrows. A small subpopulation comprising 12.3% of the total CALLA-positive cells was characterized by a high intensity of CALLA, terminal deoxynucleotidyl transferase (TdT), and MY10 expression, but low B1, common leukocyte antigen, and peanut agglutinin receptor expression. The remainder of the CALLA-positive cells displayed low intensity of CALLA expression, positivity for the common leukocyte antigen, B1 and peanut agglutinin, and negative reaction with TdT and MY10. Both CALLA-positive subpopulations were positive for HLA-DR and the pan-B cell marker B4, but negative for cytoplasmic immunoglobulin, B2 and Leu 1. BrdU labelling studies showed that a similar proportion of cells in each subpopulation was in S phase. A slightly higher proportion of the strongly CALLA-positive cells possessed the morphologic features of high nuclear/cytoplasmic (N/C) ratio and prominent nucleoli. These studies suggest that a discrete maturation step occurs among CALLA-positive marrow lymphoid cells, resulting in the loss of TdT and MY10 expression, but gradual acquisition of the B cell marker B1 and the common leukocyte antigen. The presence of B4 antigen in nearly all CALLA-positive cells suggests that both subpopulations of normal CALLA-positive marrow cells are committed to the B cell lineage.
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Ovine prolactin (o-PRL) binding to rat mammary gland membranes has been shown to vary during the estrous cycle in the normal rat. In this study we report the characteristics of o-PRL binding to mammary gland membranes throughout the estrous cycle in a new rat strain, IPL nude, which presents a total absence of lactation. Prolactin receptors were quantified in the 100 000 g pellet. The mean value of the affinity constant in IPL nude rat was 16.7 X 10(9) M-1 and no variation was observed throughout the estrous cycle. The binding capacity also remained unchanged and the values were situated between 11.6 +/- 1.1. fmoles/mg protein and 38.6 +/- 12.3 fmoles/mg protein, corresponding to the lowest values obtained in normal rat. On the day of estrus, the prolactin binding capacity in the mammary gland of the IPL nude rat was significantly different from that of normal rat. These findings confirm that prolactin certainly plays an important role in the induction or stimulation of the rat mammary gland function.
A substance presenting a beta-casein-like immunoreactivity (beta-cas-LI) was found in male serum and tissues. This beta-cas-LI was measured by a specific radioimmunoassay using a purified beta-casein and an anti beta-casein kindly supplied by L. M. Houdebine. Serial dilutions of serum or tissues samples showed a good parallelism to the standard curve. In male rat, beta-cas-Li was found in all sera and in some tissues = mammary gland, prostate and testis which contained respectively 6,200, 408 and 38 ng per organ. beta-cas-LI value in the serum was regulatable. Hypophysectomy and long-term castration strongly reduced basal levels. Insertion of testosterone silastic capsules (25 mg/capsule) was able to restore control values, while estradiol (E2) (4 mg/kg E2 valerianate) to castrated or intact rats increased serum beta-cas-LI above basal values. In conclusion, these results showed, for the first time, the presence in male rat serum and tissues of a beta-casein immunoreactive-like substance. Moreover, this beta-cas-LI seemed to be under pituitary and gonad regulation.
To detect the presence of meconium and blood, we determined coproporphyrin and hemoglobin in 78 amniotic fluid samples, classified according to their visual aspect as clear (n = 45) or meconium-stained (n = 33). Among the 33 samples visually judged as meconial, a comparison of the results of their biochemical analysis with the mean values for clear amniotic fluids showed that only five of the 33 were contaminated solely with meconium. Seven others were exclusively bloody, and 19 were meconial and bloody. In two, the contaminant was neither meconium nor blood. Evidently, when the fluid is brownish, simple visual examination does not suffice for distinguishing meconium from old blood or other pigments. We propose a simple, rapid, and reliable method for simultaneously measuring contamination with meconium or blood.
A retrospective review was undertaken at Mount Sinai Medical Center of Miami Beach for patients aged 70 and greater undergoing colon resection between January 1, 1983 and December 31, 1983. These resections were performed for carcinoma 67.3 per cent, diverticular disease 10.9 per cent, and other indications 21.8 per cent. The operations were performed by different surgeons with a wide spectrum of procedures and associated simultaneous procedures. The morbidity and mortality were reviewed. Complications occurred in 27.7 per cent (38 complications in 28 patients). The complication rate was highest in those with diverticular disease. The overall mortality rate was 4.95 per cent with a zero mortality in patients undergoing elective colon resections. It would appear that with careful monitoring and avoidance of emergency surgery, colon resection can be safely undertaken in this elderly portion of the population.
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Structural conservation of cytosolic phosphoenolpyruvate carboxykinase protein and mRNA sequence was found in all species examined from rodents to human. The mitochondrial isoenzyme, in all species tested, represents a distinct protein. Moreover, irrespective of the ratio of cytosolic to mitochondrial isoenzyme, cytosolic phosphoenolpyruvate carboxykinase activity in the human as in the rat is controlled at the level of gene expression and through the same multiple hormonal stimulation. This evolutionary conservation of the cytosolic phosphoenolpyruvate carboxykinase structure and mode of regulation supports the enzymes' physiological importance in mammals.
During the Middle Ages, an integral part of the therapy for certain ailments included supplication to "patron" saints for possible divine intervention. Through legends surrounding his life, St. Fiacre, a 7th century Irish monk, has become the patron saint for hemorrhoid sufferers.
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An unusual case of colitis cystica profunda is described. The patient presented with intestinal obstruction due to a polypoid mass in the descending colon, which was diagnosed as colitis cystica profunda after the patient underwent colectomy. Three other separate lesions were present in the ascending, transverse, and sigmoid colon. There was no antecedent or associated colonic disease. The disease recurred 1 yr later in the remaining colon and rectum.
Considerable evidence documents the importance of co-factors, including the immune response, in expression of oncogenicity of tumour viruses. To determine whether a common protozoal infection that can depress lymphocyte function alters manifestations of oncogenic virus infection, a mouse model of Toxoplasma infection with depressed T lymphocyte function was developed. In this model, Toxoplasma depressed blastogenic transformation to the T-cell mitogen Concanavalin A and primary antibody response to sheep red blood cells which requires T cell help. Uninfected and Toxoplasma-infected mice were then infected with Moloney leukaemia or Moloney sarcoma viruses and development of lymphoma and sarcoma were evaluated. Toxoplasma infection, which induced depression of T-cell function, decreased the incidence of Moloney sarcoma virus induced rhabdomyosarcomas but did not alter progression or regression of tumour in those mice that developed tumour. Conjoint infection with Toxoplasma and Moloney leukaemia virus did not increase incidence of lymphoma when compared with incidence of lymphoma in mice infected with Moloney leukaemia virus alone.
Ependymomas of the sacrococcygeal region almost always arise on the posterior aspect of the sacrum in the soft tissues and subcutaneous tissues of this region. The predominant histologic type of ependymoma in the sacrococcygeal area is myxopapillary. We report a case of myxopapillary ependymoma arising in the presacral area and presenting clinically as an abdominal mass. Ependymomas arising on the ventral aspect of the sacrum are exceedingly rare, and only 24 previous cases have been reported in the English literature. While dorsal myxopapillary ependymomas occasionally metastasize, there have been no reports of metastasis in the presacral tumors of this type.
The purpose of this study was to determine the effect of dietary cholesterol on biliary lipids in subjects with and without gallstones. Twelve patients with asymptomatic gallstones (six men, six women) were assigned diets containing 500, 750, and 1000 mg cholesterol daily for 3-wk periods in random sequence. Seven healthy women similarly were assigned diets containing 500 and 1000 mg cholesterol daily. With increasing dietary cholesterol in patients with gallstones, biliary saturation indices and molar percents of cholesterol and phospholipids increased significantly while molar percent of biliary bile acids decreased significantly. With increasing dietary cholesterol in healthy women, the biliary saturation index and molar percent of cholesterol increased significantly; the mean saturation index exceeded unity on the diet containing 1000 mg cholesterol daily. In conclusion, augmented dietary cholesterol for brief periods increased biliary cholesterol saturation in subjects with and without gallstones.
A 14-year-old boy presenting with a chest wall mass, pulmonary infiltrate, and scoliosis was found to have thoracic actinomycosis with distal vertebral involvement. Review of the medical literature for the past 25 years revealed only 23 other pediatric cases of thoracic actinomycosis. Clinical, standard radiological, and microbiological findings can be nonspecific. The diagnosis is dependent on a high index of suspicion. A long course of penicillin is the treatment of choice. Body computed tomography is a useful diagnostic aid and is helpful also in evaluating response to therapy.
As described, CT is a noninvasive method for providing detailed views of both the soft and hard tissues of the TMJ region. Because internal derangements of the joint involve both of these structures, CT can provide an invaluable tool in the study, diagnosis, and treatment of various disorders of this nature. It is extremely important, however, to create a close working relationship with the radiologist who will be performing these studies. Only with adequate clinical study and information communicated to the radiologist can true benefits be obtained. As CT scans are available nationwide, this technique should be available to nearly any practitioner in the country. CT can be useful in both diagnostic and therapeutic modalities. On a diagnostic basis, it can provide a tomographic study of the osseous structures of the condyle, fossa, articular eminence, and surrounding hard tissues. By varying the slices, views of the medial and lateral poles as well as the central portions of the region, can be obtained. In this way, various arthroses, tumors, cysts, fractures, true ankylosis, neoplasias, developmental abnormalities, and other bony abnormalities can be clearly found. Therapeutically, CT can evaluate the success of treatment aimed at reestablishing proper disk-condylar relationships. However, the major advantage of TMJ CT is the observation of the soft tissue of the articular disk. By the use of CT, especially enhanced by the blink mode, we can see how the disk relates to the condyle. If a series of views are taken in both the closed and open position, we can observe the disk-condylar relationship during this range of motion.(ABSTRACT TRUNCATED AT 250 WORDS)
In this study, aimed at investigating whether dopaminergic regulation of prolactin could be implicated in the hypoprolactinaemia observed in the IPL nude rat, dopaminergic inhibition of prolactin was suppressed using a catecholamine synthesis inhibitor alpha-methyltyrosine (MT) and a dopaminergic antagonist sulpiride. Adult male rats (IPL nude and normal) were injected through implanted atrial cannulae with either MT (250 mg/kg) or physiological saline (control). Rats were decapitated 2 h after the injection. Plasma prolactin levels, compared with basal values, increased by 15.6 +/- 1.9 (S.E.M.)- and 5.89 +/- 0.6-fold in IPL nude and normal rats respectively. This difference was highly significant. The pituitary prolactin content was decreased in both groups. In a second experiment, adult male IPL nude or normal rats were injected with either sulpiride (1 mg/kg) or saline and decapitated 2, 4, 8, 12, 14 and 24 h later. Plasma prolactin levels, compared with basal values, were increased in rats injected with sulpiride by 9.2 +/- 1.8 and 3.4 +/- 0.7-fold in IPL nude and normal rats respectively. The pituitary prolactin content was reduced more in IPL nude than in normal sulpiride-injected rats. These data suggest that prolactin secretion, as well as synthesis, is under an increased dopaminergic inhibition in the male IPL nude rat.