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M Goldman

Publications and source records attributed to M Goldman.

At least 487 records · Page 27Linked to original sources
PubMed1987

Non-invasive endoscopic technique to assess gastrointestinal perfusion.

Changes in mucosal blood flow may occur in many gastrointestinal disorders, but assessment is impossible without a non-invasive in vivo technique. We have compared endoscopic laser Doppler (LD) with oxygen electrode (OE) measurements in a dog isolated colon preparation, using variable perfusion measured with an electromagnetic flow probe. At maximum flow, LD measurements were made at three sites to compare mucosal with serosal readings. Flow rate was varied (1-38 ml/min) and measurements of microcirculatory flux obtained using LD, and of oxygen tension using a serosal OE. A progressive trend towards increasing flux was demonstrated from caecum to rectum-serosa: 46.8 +/- 18.7 V (caecum), 52.6 +/- 17.9 V (mid-colon) and 61.3 +/- 17.6 V (rectum). A parallel trend was observed in mucosal values: 41.1 +/- 18.2 V (caecum), 45.7 +/- 15.2 V (mid-colon) and 54.1 +/- 15.1 V (rectum). At all sites, serosal and mucosal values were not significantly different (Student's t test). LD serosal values correlated significantly with EM flow (r = 0.544, 0.01 greater than P greater than 0.001). A similar linear correlation was found between OE and EM flow (r = 0.65, P less than 0.001). Oxygen tension measurements varied as expected with microcirculatory flux (r = 0.441, 0.02 greater than P greater than 0.01). Endoscopic LD assessment of colonic microcirculation accurately reflects changes in blood flow.

Animals↗
PubMed1987

The effects of in vitro exposure to the neurotoxins sarin (GB) and soman (GD) on unscheduled DNA synthesis by rat hepatocytes.

Large amounts of the nerve agents, sarin (GB) and soman (GD), are part of the military chemical arsenal and small amounts are on hand in numerous U.S. research laboratories. Thus, there is a potential for accidental occupational exposure to these compounds. As part of a study of mutagenic, reproductive and subchronic effects of these agents, we measured unscheduled DNA repair synthesis in isolated rat hepatocytes after exposure to GBI (stabilized with tributylamine), GBII (stabilized with diisopropylcarbodiimide) or GD. This was done to determine whether these agents or their metabolites directly damage DNA or their related proteins. Each agent was assayed at least once over concentrations ranging from 3.0 X 10(-4) to 2.4 X 10(-3) M for GBI and GBII and 2.3 X 10(-4) to 1.8 X 10(-3) for GD and at least 3 times at 2.4 X 10(-3) M for GBI and GBII and 1.8 X 10(-3) M for GD, added as 20% of the culture medium. In all assays, no increase in the level of DNA synthesis was observed. On the contrary, significant decreases in repair synthesis were seen in hepatocytes exposed to GBI or GBII. The decreases in DNA synthesis seen in response to GD were less marked and not significant. These observations were not related to cell death, since 8 of 10 assays performed showed no significant decrease in the amount of DNA present in cultures exposed to the nerve agents compared to the negative controls. Our results suggest that the agents GBI, GBII and GD may either inhibit the repair of DNA or protect DNA from damage.

2-Acetylaminofluorene↗
PubMed1987

Low dose low osmolar intravenous urography.

A prospective double blind randomised trial using 25 ml of Hexabrix 320 (ioxaglate, May and Baker), Niopam 370 (iopamidol, Merck) or Omnipaque 350 (iohexol, Nycomed) intravenous urography was carried out. The results showed no perceptible difference in the diagnostic quality of urograms with each of the media. An additional 25 ml of contrast medium was required by 4% of patients in order to obtain a satisfactory examination. We recommend that a dose of 25 ml of low-osmolar medium be used for all patients with the exception of the obese, those taking diuretics or those who have renal impairment.

Adolescent↗
PubMed1987

The normal pericardium does not affect left ventricular function.

Whether the normal pericardium exerts a constraining effect on left ventricular (LV) diastolic compliance and/or systolic function is controversial. Left ventricular filling and performance were studied in 15 patients by two-dimensional transesophageal echocardiography (2D-TEE) measuring end-diastolic area (EDa), end-systolic area (ESa), ejection fraction area (EFa), and hemodynamics immediately pre- and post-pericardiotomy. To diminish the influences of other variables such as surgical stimulation, chest wall constraint, and autoregulation, measurements were performed in deeply anesthetized patients with the chest fully opened immediately before and after pericardiotomy (PC). No significant echocardiographic or hemodynamic changes were observed after PC. Although alterations in compliance cannot be excluded, no significant changes in LV diastolic filling (EDa, pulmonary capillary wedge pressure [PCWP]) or systolic performance (EFa, cardiac output [CO]) were found. Therefore, it is concluded that the normal pericardium does not exert a measurable constraining effect on LV performance.

Coronary Artery Bypass↗
PubMed1987

Skin blood flow: a comparison of transcutaneous oximetry and laser Doppler flowmetry.

In normal limbs skin blood flow (SBF) falls on standing, but in ischaemic limbs there is a characteristic blush on dependancy. We studied the effect of changing posture in a range of ischaemic limbs, using two non-invasive techniques--laser Doppler (LD) and transcutaneous oximetry (TcPO2). Warmed TcPO2 and LD probes were placed over the first metatarsal cleft and SBF recorded with the limb horizontal, dependant and elevated. Ankle to brachial pressure ratios (A:B) were also measured. Twelve patients with lower limb ischaemia, mean A:B ratio 0.5 +/- 0.21 (+/- S.D.) were compared with 21 asymptomatic controls, mean A:B ratio 1.2 +/- 0.15. In the controls, neither TcPO2 nor LD values changed significantly with limb position. Both flux and oxygen tension were significantly lower in ischaemic limbs in all positions; on lowering the ischaemic limb, flux unexpectedly rose to 23.5 +/- 17.7 V from a mean of 14 + 9.0 V (horizontal). Both TcPO2 and LD correlated well with A:B ratio in two positions: horizontal r (TcPO2) = 0.73, r(LD) = 0.57; elevated r(TcPO2) = 0.78, r(LD) = 0.68. Overall there was a highly significant correlation between LD and TcPO2 (r = 0.6, P less than 0.001, Student's test), but this was strongest in the elevated position (r = 0.87, P less than 0.001). LD and TcPO2 relate to A:B ratio and to each other, particularly in the stressed limb; in the well perfused limb, the poorer correlation suggests skin perfusion is not linearly related to tissue oxygen tension.

Blood Gas Monitoring, Transcutaneous↗
PubMed1987

Laser Doppler assessment of skin blood flow in arteriopathic limbs.

In severely ischaemic lower limbs, the skin response to changing posture from lying to standing is a diagnostic flush. We investigated this observation by measurements of the microcirculation using the non-invasive laser Doppler technique. Eleven patients with ankle: brachial pressure (A:B) ratios less than 0.7 were compared with 13 age-matched controls (A:B ratios greater than 1). In normal subjects, mean horizontal skin blood flow (SBF) was 30.2 +/- 14.9 (+/- SD), significantly greater than mean SBF in the ischaemic group: 12.4 +/- 9.2 (P less than 0.01, Student's t test). Mean SBF fell in the normal group on dependency to 27.5 +/- 16.4 but this change was not significant. Unexpectedly mean SBF rose in the ischaemic limbs to 20.7 +/- 13.8 (P less than 0.05). The pattern of SBF response to change in posture is different in normal and arteriopathic limbs.

Aged↗
PubMed1987

Avascular necrosis. A case report.

This case report is of a 60-year-old man with left hip avascular necrosis that initially was diagnosed as low back pain syndrome.

Back Pain↗
PubMed1987

Chimerism and cytotoxic T lymphocyte unresponsiveness after neonatal injection of spleen cells in mice. Effects of T cell depletion and of a semiallogeneic or fully allogeneic inoculum.

Newborn Balb/c mice received a single neonatal injection of either (A/J x Balb/c) F1 hybrid spleen cells, T-cell-depleted (A/J x Balb/c) F1 hybrid spleen cells, or T-cell-depleted fully allogeneic A/J spleen cells. Chimerism was followed longitudinally during the life span by the detection of circulating donor allotype. At sacrifice, the percentage of donor cells in the spleen was measured, and cytotoxic T lymphocyte (CTL) reactivity to the tolerogen was tested. We found that T cell depletion of the semiallogeneic inoculum did not modify its capacity to generate persistent chimerism and CTL tolerance, while T-cell-depleted allogeneic cells were intrinsically deficient both in the induction and in the long-term maintenance of chimerism and CTL unresponsiveness.

Animals↗
PubMed1987

Pregnancy and humoral immune response in mice chronically infected by Trypanosoma cruzi.

The effect of pregnancy on the humoral immune response induced by Trypanosoma cruzi was studied in groups of chronically infected and pregnant mice (IP) or chronically infected and nonpregnant mice (INP) of strain BALB/c. Groups of noninfected and nonpregnant mice (NINP) or noninfected and pregnant mice (NIP) served as controls. The pregnant mice were killed on day 17 of pregnancy. Anti-T. cruzi immunoglobulin G (IgG) and IgM antibodies, detected by immunofluorescence or enzyme-linked immunosorbent assay or both, underwent a pregnancy-associated decrease of 20 to 40%, whereas complement-mediated lytic antibodies were unaffected by pregnancy. Immunoblotting analysis indicated identical specificities of the anti-T. cruzi antibodies in IP and INP groups. The levels of all the immunoglobulin isotypes (particularly IgG2a and IgG3), circulating immune complexes, rheumatoid-like factor, and anti-DNA antibodies were considerably increased during chronic infection (NINP versus INP), which could be related to the high degree of polyclonal B-cell activation occurring in T. cruzi infection. However, pregnancy significantly decreased (by 20 to 60%) such parameters. IgG levels were particularly affected (by 40 to 60%), and the decreases could be ordered as follows: IgG3 greater than IgG2a greater than IgG1 greater than IgG2b for IP versus INP. Comparisons between the noninfected groups indicated differences only in IgG levels. These results indicate the following. (i) The specific humoral anti-T. cruzi immune response is weakly affected by pregnancy, which is not sufficient to modify the course of the mother's infection. (ii) Pregnancy does not modify the expression of the anti-T. cruzi antibody repertory. (iii) Pregnancy reduces the polyclonal B-cell activation, particularly the levels of the IgG isotypes undergoing the greatest activation.

Animals↗
PubMed1987

Abdominal tuberculosis in East Birmingham--a 16 year study.

Abdominal tuberculosis, although rare, occurs mainly in immigrants from the Indian subcontinent. Such people comprise 13.5% of our local population and contributed 90% of a series of 72 patients presenting in the last 16 years; a local disease incidence of 1:6000 for Asian immigrants. Men and women were equally affected, but on average women were much younger. Diagnosis was made from one month to 10 years after immigration. No clinical feature was diagnostic, but abdominal pain, night sweats and weight loss occurred in more than half the patients. The erythrocyte sedimentation rate (ESR) was elevated in 95% and no patient tested had a negative Mantoux test. In 20 patients diagnosis was by clinical suspicion and response to therapeutic trial. In 52, including 39 who had a laparotomy, histological and culture material was obtained but these patients fared no better. Only one organism was resistant (to streptomycin) and rapid response to chemotherapy was the rule. Successful outcome was not related to the type of presentation, operative findings or specific chemotherapeutic agents. We would suggest that in Asians presenting with difficult-to-diagnose abdominal symptoms accompanied by malaise, raised ESR and a positive Mantoux test, a therapeutic trial of anti-tuberculous therapy should precede diagnostic laparotomy.

Adolescent↗
PubMed1987

ECG abnormalities in patients with epilepsy.

Some investigators believe that patients with epilepsy are at increased risk of sudden death, perhaps because of cardiac arrhythmias. We studied 338 patients with epilepsy referred for simultaneous ambulatory EEG/ECG monitoring. High-risk cardiac arrhythmias were detected in 18 (5.3%) patients while low-risk arrhythmias or negative studies were found in the others. Fifty-six electrographic seizures were seen in 17 patients, but no associated ventricular arrhythmias or conduction defects were identified. We conclude that the incidence of serious cardiac arrhythmias predisposing to sudden death is not increased in patients with epilepsy.

Arrhythmias, Cardiac↗