Biomedical subjects

M Goldstein

Publications and source records attributed to M Goldstein.

At least 127 records · Page 7Linked to original sources

PubMed1996

Myocardium is a major source of proinflammatory cytokines in patients undergoing cardiopulmonary bypass.

Proinflammatory cytokines, such as tumor necrosis factor-alpha, interleukin-6, and interleukin-8, and anti unflammatory cytokines, such as interleukin-10, may play an important role in patient responses to cardiopulmonary bypass. We sought to define whether the myocardium and the lungs serve as important sources of these cytokines under conditions of cardiopulmonary bypass. Ten patients (age 64 +/- 3 years, mean +/- standard error of the mean) undergoing elective coronary artery bypass grafting were monitored with an arterial catheter, a coronary sinus catheter, and pulmonary artery catheter. Plasma levels of tumor necrosis factor-alpha, interleukin-6, interleukin-8, and interleukin-10 were measured simultaneously in peripheral arterial blood, coronary sinus blood, and mixed venous blood before heparin administration, 1 minute before aortic crossclamping, 5 minutes after aortic declamping, and at 0.5, 1, 1.5 and 2 hours after aortic declamping. The durations of cardiopulmonary bypass and aortic crossclamping were 114 +/- 9 and 64 +/- 5 minutes, respectively. Levels of tumor necrosis factor-alpha and interleukin-6 were significantly higher in coronary sinus blood than in arterial blood after aortic declamping. Tumor necrosis factor-alpha and interleukin-6 levels were also higher in mixed venous blood than in arterial blood within 1 hour after declamping. There were no significant differences among the three sampling sites with respect to interleukin-8 and interleukin-10 levels. In one patient who had postoperative myocardial infarction, however, interleukin-8 levels were three times as high as in coronary sinus blood than in arterial blood. These data indicate that the myocardium is a major source of tumor necrosis factor-alpha and interleukin-6 in patients undergoing cardiopulmonary bypass. The lungs may consume rather than release proinflammatory cytokines in the early phase of reperfusion. The source under these conditions of the antünflammatory cytokine interleukin-10 remains to be determined.

Aged↗

PubMed1996

A simplified method of epididymal sperm aspiration.

We present a simple technique of epididymal sperm aspiration that uses inexpensive and readily available materials. Men undergoing epididymal reconstruction with vasoepididymostomy or autogenous sperm reservoir had sperm aspiration for cryopreservation. Mean total and total motile sperm per aspirate recovered from 25 men have been 25.1 +/- 4.8 x 10(6) and 4.0 +/- 1.4 x 10(6), respectively. Two ongoing pregnancies have been achieved with intracytoplasmic sperm injection using thawed epididymal sperm. Sperm aspiration and cryopreservation maximize a couple's fertility potential with a single procedure and provide a viable fertility alternative to a second surgical procedure in the event of a primary reconstructive failure.

Epididymis↗

PubMed1996

Dopaminergic transmission in the rat retina: evidence for volume transmission.

The study was designed to determine whether dopaminergic neurotransmission in the retina can operate via volume transmission. In double immunolabelling experiments, a mismatch as well as a match was demonstrated in the rat retina between tyrosine hydroxylase (TH) and dopamine (DA) immunoreactive (ir) terminals and cell bodies and dopamine D2 receptor-like ir cell bodies and processes. The match regions were located in the inner nuclear and plexiform layers (D2 ir cell bodies plus processes). The mismatch regions were located in the ganglion cell layer, the outer plexiform layer, and the outer segment of the photoreceptor layer, where very few TH ir terminals can be found in relation to the D2 like ir processes. In similar experiments analyzing D1 receptor like ir processes versus TH ir nerve terminals, mainly a mismatch in their distribution could be demonstrated, with the D1 like ir processes present in the outer plexiform layer and the outer segment where a mismatch in D2 like receptors also exists. The demonstration of a mismatch between the localization of the TH terminal plexus and the dopamine D2 and D1 receptor subtypes in the outer plexiform layer, the outer segment and the ganglion cell layer (only D2 immunoreactivity (IR)) suggests that dopamine, mainly from the inner plexiform layer, may reach the D2 and D1 mismatch receptors via diffusion in the extracellular space. After injecting dopamine into the corpus vitreum, dopamine diffuses through the retina, and strong catecholamine (CA) fluorescence appears in the entire inner plexiform layer and the entire outer plexiform layer, representing the match and mismatch DA receptor areas, respectively. The DA is probably bound to D1 and D2 receptors in both plexiform layers, since the DA receptor antagonist chlorpromazine fully blocks the appearance of the DA fluorescence, while only a partial blockade is found after haloperidol treatment which mainly blocks D2 receptors. These results indicate that the amacrine and/or interplexiform DA cells, with sparse branches in the outer plexiform layer, can operate via volume transmission in the rat retina to influence the outer plexiform layer and the outer segment, as well as other layers of the rat retina such as the ganglion cell layer.

Animals↗

PubMed1996

Regulation of L-DOPA biosynthesis by site-specific phosphorylation of tyrosine hydroxylase in AtT-20 cells expressing wild-type and serine 40-substituted enzyme.

De novo L-DOPA biosynthesis was studied in stably transfected AtT-20 cells expressing wild-type- or [Leu40]-recombinant tyrosine hydroxylase (rTH). Basal rates of DOPA accumulation were much higher by cells expressing rTH in which Leu was substituted for Ser4O (S40L-rTH) than by those expressing wild-type rTH (WT-rTH). Treatment of WT-rTH cells with forskolin produced an increase in DOPA accumulation and a concomitant increase in WT-rTH phospho-Ser40 content, whereas DOPA production by cells expressing S40L-rTH was entirely unaffected by forskolin. After forskolin treatment of 32Pi-prelabeled cells, WT-rTH was phosphorylated at Ser8, Ser19, Ser31, and Ser40, whereas 32P incorporation into S40L-rTH was restricted to Ser8, Ser19, and Ser31. Relatively prolonged treatment of AtT-20 cells expressing WT-rTH with either a depolarizing agent (elevated potassium) or a phosphatase inhibitor (okadaic acid) increased DOPA production and increased the phosphorylation state of Ser40; but, unlike forskolin, these treatments also increased DOPA production by cells expressing S40L-rTH. Thus, the present studies demonstrate that Ser40 phosphorylation mediates forskolin-induced increases in DOPA biosynthesis directly but that mechanisms other than Ser40 phosphorylation can mediate the increases in DOPA biosynthesis produced either by depolarization or by protein phosphatase inhibition.

Animals↗

PubMed1996

Dopamine D1 receptor-mediated facilitation of GABAergic neurotransmission in the rat strioentopenduncular pathway and its modulation by adenosine A1 receptor-mediated mechanisms.

By using in vivo microdialysis it was found that one of the main functions of striatal dopamine D1 receptors is to selectively facilitate GABAergic neurotransmission in the 'direct' strioentopeduncular pathway. D1 receptors localized in the entopeduncular nucleus were also found to facilitate GABA release. However, results obtained from in vivo microdialysis, in vivo electrochemistry, immunohistochemistry and confocal laser microscopy suggested that entopeduncular D1 receptors could only be activated under pharmacological conditions. Adenosine A1 receptors were found to antagonistically modulate the D1-mediated regulation of the strioentopeduncular pathway. Furthermore, using in situ hybridization D1 and A1 receptors were shown to be colocalized in medium-sized striatal neurons. These results show that the strioentopeduncular neuron is a main locus for adenosine-dopamine interactions in the brain.

Animals↗

PubMed1996

A critical evaluation of methods for root coverage.

Gingival recession is the exposure of root surfaces due to apical migration of the gingival tissue margins. Although it seldom results in tooth loss, marginal tissue recession is associated with thermal and tactile sensitivity, esthetic complaints, and a tendency toward root caries. This article reviews the current surgical procedures for the coverage of exposed root surfaces, including their advantages and disadvantages. Today, the outcome of root coverage procedures is predictable, aesthetically acceptable, and, together with the use of guided tissue regeneration, at the forefront of regenerative procedures.

Citrates↗

PubMed1996

Reduced immunostaining for the extracellular Ca2+-sensing receptor in primary and uremic secondary hyperparathyroidism.

Most parathyroid adenomas and some pathological parathyroid glands from patients with primary parathyroid hyperplasia or severe uremic secondary/tertiary hyperparathyroidism show an elevated set-point [the extracellular Ca2+ concentration (Ca2+o) half-maximally inhibiting PTH secretion]. In the present study, we investigated whether expression of the Ca2+o-sensing receptor protein recently cloned from bovine parathyroid, a key component in Ca2+o-regulated PTH release, is altered in primary and uremic hyperparathyroidism. Using immunohistochemistry with specific antireceptor antibodies, we compared immunoreactivity of the receptor protein in 14 adenomas, biopsies of 24 normal glands from this same group of patients, and 8 hyperplastic parathyroid glands from 2 individuals with uremic hyperparathyroidism. The results show a substantial reduction in the intensity of immunostaining for the receptor protein that averaged nearly 60% for both adenomas and hyperplastic glands, as quantitated by image analysis. Although normal glands from normocalcemic controls were not available, the intensity of receptor staining in normal glands from patients with adenomas was comparable to that in normal bovine, rat, and mouse parathyroid glands. There was considerable variation in staining intensity among different pathological parathyroid glands, even in those from the same patient with secondary hyperparathyroidism. In addition, both adenomas and hyperplastic glands had, in some cases, isolated chief cells and groups of cells, sometimes around the periphery of an abnormal gland, with receptor staining equivalent to that of normal parathyroid cells, whereas the bulk of the cells in the same gland showed a marked decrease in staining. Thus, there is a variable, but substantial, reduction in the immunoreactivity of the Ca2+o-sensing receptor protein in both parathyroid adenomas and uremic hyperparathyroidism, as assessed by immunohistochemistry, that probably results from reduced expression of the receptor protein and may contribute to the increase in the set-point often observed in these patients.

Adenoma↗

PubMed1996

Research changes a health care delivery system: a biopsychosocial approach to predicting resource utilization in hospital care of the frail elderly.

The social work department of a large New York City teaching hospital has conducted practice research studies over the past five years to better improve the early identification of high risk elderly patients. A recent prospective study is presented of the relationship between functional capacity and discharge status/length of stay, the results of which directly led to a change in the inpatient delivery system. A sample of 250 randomly selected patients, 65 years or older, selected upon admission, were tested using the Katz ADL, the IADL and the Short Portable Mental Status Questionnaire (PMSQ) to distinguish those patients likely to remain hospitalized beyond medical necessity. Results of a logistic regression indicate that low functional capacity patients (IADL: Wald = 5.6; P < .02) were likely to remain beyond medical necessity. The model predicted group membership correctly 90.6% of the time. These findings have led the medical center to develop an acute care geriatric unit in cooperation with an affiliated nursing home.

Activities of Daily Living↗

PubMed1996

Presence of sperm in the pre-vasectomy reversal semen analysis: incidence and implications.

PURPOSE: We determined the incidence of sperm in the ejaculate before vasectomy reversal, and correlated this result with intraoperative and postoperative findings. MATERIALS AND METHODS: Before vasectomy reversal semen was analyzed and granulomas were palpated in 186 men. The results were correlated with intraoperative vasal fluid and postoperative semen analyses. RESULTS: Of 18 men (9.7%) with sperm present in the pre-reversal analysis 94% had sperm in at least 1 vas intraoperatively. The presence of palpable granulomas at the vasectomy site did not correlate with either pre-reversal or post-reversal semen analyses, or the presence of sperm in the vasal fluid intraoperatively. CONCLUSIONS: Sperm are present in 9.7% of pre-reversal ejaculates and predict sperm in at least 1 vas intraoperatively. These findings also suggest the possibility of late vasectomy failures.

Adult↗

PubMed1996

Urogenital anomalies in men with congenital absence of the vas deferens.

PURPOSE: We evaluated urogenital anomalies in men with congenital absence of the vas deferens. METHODS AND MATERIALS: A retrospective review was done of 104 subfertile men with congenital absence of the vas deferens (84 bilaterally and 20 unilaterally). RESULTS: Of men with unilateral or bilateral congenital absence of the vas deferens 26 and 11%, respectively, had renal agenesis. Of men with unilateral congenital absence of the vas deferens and infertility 80% had genitourinary anamalies affecting the contralateral testis. No man with congenital absence of the vas deferens and renal anomalies had cystic fibrosis transmembrane-conductance regulator (CFTR) gene mutations detected. CONCLUSIONS: Other urogenital anomalies are common for men with congenital absence of the vas deferens. CFTR gene mutations frequently contribute to maldevelopment of the vas deferens but vasal agenesis can occur without any evidence of CFTR defects. CFTR abnormalities are rarely detected in men with congenital absence of the vas deferens and renal anomalies.

Cryptorchidism↗

PubMed1995

The cholinergic innervation of the adrenal gland and its relation to enkephalin and nitric oxide synthase.

Using a monoclonal antibody against rat brain choline acetyltransferase (ChAT) the cholinergic innervation of the adult rat adrenal gland was visualized. Almost all ChAT-positive fibres contained nitric oxide synthase (NOS), whereas enkephalin (ENK) was exclusively found in ChAT fibres among adrenaline chromaffin cells. The ChAT/NOS/ENK fibres disappeared after immunological sympathectomy, indicating a preganglionic origin. ChAT was not found in the superficial peptide- and NOS containing fibre plexus in the adrenal cortex or in small or large intra-adrenal ganglion neurones under control conditions. Even after colchicine treatment only one single ChAT-positive small ganglion neurone was found. It is possible, therefore that some small intra-adrenal ganglion neurones, which express NOS- and VIP-like immunoreactivities, are noncholinergic, nonadrenergic neurones.

Adrenal Glands↗

PubMed1995

Localization of choline acetyltransferase in rat peripheral sympathetic neurons and its coexistence with nitric oxide synthase and neuropeptides.

Indirect immunofluorescence methods using a mouse monoclonal antibody raised to rat choline acetyltransferase (ChAT) revealed dense networks of ChAT-immunoreactive fibers in the superior cervical ganglion, the stellate ganglion, and the celiac superior mesenteric ganglion of the rat. Numerous and single ChAT-immunoreactive cell bodies were observed in the stellate and superior cervical ganglia, respectively. The majority of ChAT-immunoreactive fibers in the stellate and superior cervical ganglia were nitric oxide synthase (NOS) positive. Some ChAT-immunoreactive fibers contained enkephalin-like immunoreactivity. Virtually all ChAT-positive cell bodies in the stellate ganglion were vasoactive intestinal polypeptide (VIP)-positive, and some were calcitonin gene-related peptide (CGRP)-positive. After transection of the cervical sympathetic trunk almost all ChAT- and NOS-positive fibers and most enkephalin- and CGRP-positive fibers disappeared in the superior cervical ganglion. The results suggest that most preganglionic fibers are cholinergic and that the majority of these in addition can release nitric oxide, some enkephalin, and a few CGRP. Acetylcholine, VIP, and CGRP are coexisting messenger molecules in some postganglionic sympathetic neurons.

Animals↗

PubMed1995

Perfusion immunoassay for acetylcholinesterase: analyte detection based on intrinsic activity.

A quantitative, two-column, HPLC-based assay requiring only 30 min to complete is reported. Amniotic fluid proteins are first fractionated on a size-exclusion column; the fraction containing the M(r) 280,000 neural acetylcholinesterase (AChE) is then diverted to a second column, an ImmunoDetection cartridge derivatized with an anti-AChE antibody. The immobilized antibody traps the enzyme, then substrate is flowed through the cartridge and the product is detected. For a positive result, the enzyme must have a molecular mass corresponding to the neural-AChE, be recognized by the antibody and be active in converting the substrate into product. The assay is sensitive in the clinically relevant range. The method provides rapid quantitative analysis using an automated instrument projected to be suitable for screening large numbers of samples.

Acetylcholinesterase↗

PubMed1995

Constitutive heterochromatin of chromosome 1 and Duffy blood group alleles in schizophrenia.

Cytogenetic analysis was carried out in unrelated schizophrenic patients, unrelated controls and patients and family members in multiplex families. The size distribution of chromosome 1 heterochromatic region (1qH, C-band variants) among 21 unrelated schizophrenic patients was different from that found in a group of 46 controls. The patient group had 1qH variants of smaller size than the control group (P < 0.01). Incubation of phytohemagglutinin-treated blood lymphocytes with 5-azacytidine (which causes decondensation and extension of the heterochromatin) led to a lesser degree of heterochromatin decondensation in a group of patients than in the controls (7 schizophrenic, 9 controls, P < 0.01). The distribution of phenotypes of Duffy blood group system [whose locus is linked to the 1qH region (Donahue et al.: Proc Natl Acad Sci USA 61:949-955, 1968; Rouleau et al.: Genomics 7:313-318, 1990)] among 28 schizophrenic patients was also different from that in the general population. Cosegregation of schizophrenia with a 1qH (C-band) variant and Duffy blood group allele was observed in one of six multiplex families. The overall results suggest that alterations within the Duffy/1qH region are involved in schizophrenia in some cases. This region contains the locus of D5 dopamine receptor pseudogene 2 (1q21.1), which is transcribed in normal lymphocytes (Takahashi et al.: FEBS Lett 314:23-25, 1992).

Adolescent↗

PubMed1995

Item and order recognition memory in subjects with hypoxic brain injury.

Subjects with hypoxic brain injury resulting in significant cell loss in the hippocampus but not the parahippocampal gyrus or temporal lobes and normal control subjects were tested for memory impairments. The Denman Memory Scale was given to all subjects as a baseline memory assessment. All subjects were then tested for item and order recognition memory for lists of six words, pictures, abstract pictures, spatial locations, and motor responses. Results indicated that hypoxic subjects are impaired compared to control subjects on the Denman memory scale for verbal, non-verbal, and full-scale memory quotients. In addition, results indicated that compared to control subjects, hypoxic subjects displayed item and order recognition deficits for words, pictures, abstract pictures, and spatial locations. A recency effect for item recognition of abstract pictures, spatial locations, and hand positions was found. For motor response order recognition, both primacy and recency effects were found, with deficits in performance for the middle items of the list. It appears that subjects with hypoxic brain injury in the face of severe memory deficits for words, pictures, abstract pictures, and spatial locations display residual capacity for remembering the last items for spatial locations, abstract designs, and hand positions. Hypoxic subjects also display residual capacity for remembering motor responses using episodic or data-based memory.

Adult↗

PubMed1995

The effect of nasolacrimal occlusion on drug-induced mydriasis.

BACKGROUND: Nasolacrimal occlusion has been shown to improve the efficacy of some topically applied ocular drugs. The aim of this study was to investigate the effect of nasolacrimal occlusion on tropicamide-induced mydriasis. METHODS: We compared pupillary dilatation by 0.125% tropicamide with and without nasolacrimal occlusion in 40 healthy volunteers. RESULTS: Analysis of variance with repeated measures failed to show any advantage due to nasolacrimal occlusion in drug-induced mydriasis. CONCLUSION: Nasolacrimal occlusion did not increase the mydriasis obtained with 0.125% tropicamide.

Adult↗

PubMed1995

C-fos expression in vivo in human lymphocytes in response to stress.

1. Blood samples from which lymphocytes were isolated were obtained from patients immediately prior to cardiac catheterization (stress period) and again four to five hours later (post-stress period). Blood was also taken from a normal non-stressed control subject. 2. Lymphocyte c-fos mRNA was reverse transcribed followed by strand synthesis of DNA template and amplification using PCR with sequence-specific primers. 3. C-fos mRNA was detectable in lymphocytes from the normal control subject and in patient samples obtained immediately prior to cardiac catheterization, but was not detectable in patient samples obtained four to five hours later. 4. Possible mechanisms for these findings include a stress-related decrease in lymphocyte proliferation and differentiation or a negative feedback effect of the c-fos protein on transcription of the c-fos gene. 5. These findings suggest that it may be possible to monitor peripheral early gene expression as a marker for a variety of conditions including stress, psychiatric disorders and the response to psychotropic drugs.

DNA Probes↗

PubMed1995

Sodium ions attenuate the inhibitory effects of neuropeptide Y on norepinephrine release in rat hypothalamus.

Neuropeptide Y (NPY) has a wide and specific distribution both in the central and peripheral nervous systems. In the present study, we have investigated the effects of NPY on norepinephrine release in rat hypothalamus, and further examined the interaction of NPY with alpha 2-adrenergic receptors, as well as the influence of sodium ions on the modulation of norepinephrine release. In an in vitro study, NPY significantly inhibited the stimulation-evoked norepinephrine release from hypothalamic slices in a dose-dependent manner. The alpha 2-adrenergic receptor agonist, UK 14,304, also reduced the stimulation-evoked norepinephrine release. A low concentration of NPY, which had no effects on its own, significantly potentiated the inhibitory effect of UK 14,304 on the stimulation-evoked [3H]norepinephrine release. The blockade of alpha 2-adrenergic receptors by RX 781094 diminished the inhibitory effects of NPY on norepinephrine release. Pretreatment of slices with pertussis toxin (a potent inhibitor of the Gi-proteins) significantly attenuated the suppressive effects of NPY and UK 14,304 on norepinephrine release. When the sodium concentration of the perfusion medium was increased, the inhibitory effects of NPY and UK 14,304 on norepinephrine release were significantly reduced. These results show that NPY might inhibit norepinephrine release that is partially mediated by alpha 2-adrenergic receptors and the pertussis toxin-sensitive Gi-proteins in rat hypothalamus. Moreover, less suppressive effects of NPY and UK 14,304 on norepinephrine release in the presence of excess sodium ions suggest that sodium ions might actively participate in regulating the NPY and alpha 2-adrenergic receptor mediated functions in the central nervous system.

Adrenergic alpha-Agonists↗