A radioassay for dopamine-beta-hydroxylase activity.
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Biomedical subjects
Publications and source records attributed to M Goldstein.
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Diffuse 'histiocytic' lymphoma (DHL) is heterogeneous pathologically, consisting of four subtypes within Lukes-Collins; large-cleaved (LC), large non-cleaved (LNC), immunoblastic sarcoma of B cells (B-IBS), and immunoblastic sarcoma of T-cells (T-IBS). This heterogeneity is also recognized in the Cooperative Working Formulation on non-Hodgkin's lymphoma. Prior studies have suggested clinical heterogeneity of DHL as well, although conclusions were hampered by small numbers, and lack of therapeutic uniformity. We treated 57 patients with advanced DHL, using BACOP: 22 LNC, 16 T-IBS, 13 B-IBS, six LC. Complete remission rate for LNC was 64 per cent (14/22); B-IBS was 54 per cent (7/13); LC was 33 per cent (2/6); T-IBS was 25 per cent (4/16). (p = 0.10). Median survival for LNC was 27.8 months, B-IBS was 25.9, LC was 14, T-IBS was 12.0. The survival was significantly shorter for T-IBS patients when compared to the others (p = 0.01). By multi-variate analysis, histologic subtype (p = 0.02), age (p = 0.03), and stage (p = 0.06) were significant and independent prognostic variables in predicting survival. We conclude that LNC may respond the most favourably to BACOP, whereas alternative regimens appear necessary for patients with T-IBS.
Numerous groups of small tubules were observed in the semen of two infertile patients. These structures were about 80 nm in diameter and could be observed within larger concentric tubules. They did not resemble typical microtubules, and did not appear similar to unit membrane.
Previously spermatozoa in the semen of vasectomized men were reported in 62 of 63 specimens from 24 men 2 to 31 years postvasectomy (Freund and Couture, 1982). A morphologic basis and term, "microrecanalization," was proposed for this observation. Serial sections (5 mu at 200-mu intervals) of 40 specimens removed at vasovasostomy from 20 men (2 to 14 years postvasectomy) were examined and microcanals (small epithelial-lined channels) were demonstrated in 27 specimens from 18 men. In nine of the 27 specimens, spermatozoa or sperm heads were found within the microcanals. Microcanals occurred in smooth muscle, connective tissue and scar tissue, in each segment, testicular, central and abdominal, in the presence or absence of the vas deferens. Microcanal continuity was traced for 200 to 1140 microns by computerized image analysis. Microrecanalization is characterized by the absence of inflammation or sperm extravasation and is histologically distinct from vasitis nodes or sperm granuloma. Microrecanalization provides morphologic and physiologic bases for the protection of the testis and maintenance of spermatogenesis in man after vasectomy.
Microsurgery requires considerable practice before any attempt is made at clinical application. Live animals represent the ideal training medium; however, unlimited access to the animal laboratory is not always possible. In such situations, segments of fresh human placenta provide ideal specimens for microsurgical practice. They are readily available and abundant in a variety of vessels, and require a minimum of dissection.
OBJECTIVES: The purpose of this paper is to examine the characteristics of smokers who adhere to a hospital smoking ban, compared to those who do not. DESIGN: The data presented in this paper are baseline and discharge survey data collected among hospitalized smokers. SETTING: This study was conducted in two teaching hospitals in a northeastern city. PATIENTS/PARTICIPANTS: The subjects were 358 smokers who participated in a larger smoking intervention trial. MAIN RESULTS: Seventy-six percent of the subjects reported adhering to the smoke-free policy during their hospital stay. In a multivariate model, demographic factors that predicted adherence included being older, having shorter length of stay, not reporting recreational drug use in the previous 12 months, and not having alcohol-related problems. Smoking history variables that predicted adherence included having had at least 24 h of abstinence in the 7 days prior to hospitalization; self-efficacy variables (e.g., confidence in ability to quit smoking in 1 month and less anticipated difficulty refraining from smoking during hospitalization) also predicted adherence. CONCLUSIONS: Understanding the factors that predict adherence to health care policies can provide useful information for health promotion interventions in a medical setting. The implications of these findings are discussed.
Evidence exists for a negative correlation between Parkinson's disease and smoking. The present and previous studies indicate that nicotine treatment can markedly alter the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced neurotoxicity in the black mouse based on biochemical determinations of dopamine (DA), 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) levels in neostriatum and substantia nigra 2 weeks after MPTP injection. Acute intermittent treatment with (-)nicotine starting 10 min before the MPTP injection partly protected against MPTP-induced neurotoxicity in the neostriatum and substantia nigra. Also, a partial protection was observed in the substantia nigra when (-)nicotine was given together with MPTP in an acute intermittent treatment schedule. Conversely, chronic infusion of (-)nicotine via minipumps produced a dose-related enhancement of MPTP-induced DA neurotoxicity in the neostriatum. It is suggested that the protective activity of nicotine in the MPTP model is related to a blockade of MPP+ uptake into the DA cells via increased DA release. Conversely, the nicotine enhancement of MPTP-induced DA toxicity is suggested to be caused by a failure of the nicotinic cholinoceptors to desensitize to the chronic (-)nicotine exposure, leading to increased chronic influx of Na+ and Ca2+ ions via the ion channels of the nicotinic cholinoceptors located on the DA neurons with associated increased Ca ion toxicity and increased energy demands.
The present method is exemplified on coronal sections of the medulla oblongata containing phenylethanolamine-N-methyltransferase (PNMT) immunoreactive nerve cell bodies and their processes and on coronal sections of the pons containing the locus coeruleus, where PNMT immunoreactive nerve terminals have been demonstrated together with the dopamine-beta-hydroxylase immunoreactive nerve cell bodies. Morphometric analysis of the processes (both length and branches) and of the nerve terminals involve as a first step the division of the area under study into squares 100 microns wide, which are superimposed on a Cartesian plane. The uniformity of the density distribution of the nerve terminals and the processes (branches or length) can be analyzed by Lorenz curves, which in a quantitative way can measure the degree of unevenness and thus represent a measure of concentration. A concentration index can therefore be calculated. By the use of the densitometric approach it also becomes possible to study the density distribution of the nerve terminals with the highest antigen contents. The present method will make it possible to quantitate morphological changes occurring in processes and nerve terminals of transmitter-identified neurons.
A new technique is described which makes it possible to measure several substances and parameters related to axonal transport in peripheral nerves. The technique is based on histofluorescent techniques and measures accumulated amounts of fluorescent substances, e.g. proximal to a crush or local cooling of the nerve. Sections from nerves, treated according to the FIF method for visualization of catecholamines or for immunofluorescence, are placed in a cytofluorimeter (Leitz MPV 2). The nerve sections are passed under a measuring slit by a motor-driven cross-table and the fluorescence intensity is continuously registered via a recorder with integrator which gives a graphical "nerve-accumulation profile." Comparisons between accumulation curves obtained with the cytofluorimetric scanning technique and biochemically determined accumulation curves of noradrenaline, dopamine-beta-hydroxylase and tyrosine-hydroxylase in the sciatic nerve following crush operations, demonstrated a striking similarity. With this technique it is possible to semiquantify the accumulated amount of a fluorescent substance, study morphology, perform morphometry and photographical documentation in the same section. This scanning technique may prove useful, since the accumulation and distribution of several substances in consecutive sections, along the length of a nerve, can be demonstrated graphically using superimposed curves.
With the indirect immunofluorescence technique using antisera to three catecholamine synthesizing enzymes, labeled periglomerular cells as well as their intraglomerular processes were observed in the turtle olfactory bulb. These cells could also be recognized in the EPL and the glomerular layer. Unlabeled periglomerular cells were also seen. Thick labeled processes (presumably dendrites) entered the glomerular neuropil, and there formed a dense network, with numerous terminal varicosities. These results support the existence of a unique, homologous dopaminergic subdivision of the periglomerular interneurons throughout classes of vertebrates. In addition, a second type of weakly tyrosine hydroxylase immunoreactive neurons was observed in the outer part of the granule layer. Dopamine beta-hydroxylase positive fibers were seen in the granule, mitral and external plexiform layers.
A wealth of evidence suggests that catecholamines influence gonadotrophin secretion. To assess whether this interaction involved LHRH cells or their processes, the distribution of the catecholamine synthesizing enzyme, tyrosine hydroxylase (TH) was examined with reference to the LHRH system in the adult male mouse brain. Alternate 30-50 micron sections cut on a vibrating microtome were stained immunocytochemically for TH and LHRH. These studies revealed the presence of catecholamine fibers in the areas of LHRH cells. Co-localization of TH and LHRH with a dual immunoperoxidase technique in single 20-25 micron sections showed a juxtaposition of catecholamine fibers on LHRH cells and their dendrites. All LHRH cells did not appear contacted. In addition, LHRH axons were in close apposition to the dopamine cells of the arcuate nucleus and periventricular hypothalamus. Within the median eminence, the anatomical distribution of LHRH and TH was differentially organized with few areas of overlap. These results support a direct action of catecholamines on the LHRH system and suggest that LHRH may influence dopamine function.