Search PubMed⌕ Search

Biomedical subjects

M Cohen

Publications and source records attributed to M Cohen.

At least 739 records · Page 41Linked to original sources
PubMed1986

Viruses, neurodevelopmental disorder and childhood psychosis.

Four cases are described of prepubertal boys in whom the convergence of neurodevelopmental disorder, viral infection and psychosis seemed more than coincidental. Review of the literature highlights the possibility that viral infection of the central nervous system may play a contributory role in childhood psychosis. Whilst it is essential to avoid a reductionist stance when investigating these difficult conditions, the emergence of potent anti-viral treatments and sophisticated methods of identifying the presence of viral infection should encourage us to consider more carefully the relevance of viruses in childhood psychosis.

Chickenpox↗
PubMed1986

Septum of the gallbladder, clinical implications and treatment.

We report four patients with a congenital gallbladder septum whose symptoms resembled those of cholelithiasis, in one case giving rise to acute cholecystitis. Cholecystectomy relieved symptoms in all cases and examination of the operative specimen confirmed the clinical diagnosis and X-ray findings. Ultrasonography made a positive diagnosis in the last two cases and no stones were found in any of the cases described. Cholecystectomy is advocated in symptomatic patients with this condition, even when gallstones are not present.

Adult↗
PubMed1986

Cholecystitis: detection with MR imaging.

The role of magnetic resonance (MR) imaging in the detection of gallbladder disease was evaluated in 39 individuals (16 healthy, five with asymptomatic gallstones, and 18 with clinical symptoms of gallbladder disease). MR imaging was performed after they fasted for 12 hours. Imaging sequences included a combination of repetition times (TR) of 0.5 and 1.5 sec and echo times (TE) of 28 and 56 msec. On the images obtained at TR = 0.5 sec and TE = 56 msec, gallbladder bile was hyperintense compared with the liver in all healthy and asymptomatic subjects and was hypointense (n = 9), isointense (n = 4), or hyperintense (n = 5) in symptomatic patients, eight of whom had surgical confirmation of cholecystitis. Comparison of normal versus pathologically proved cases for the presence of gallbladder disease yielded a specificity of 100%, sensitivity of 75%, and a significant difference of P less than .01. Thus, with a pulse sequence of TR = 0.5 sec and TE = 56 msec, MR was sensitive in detecting gallbladder disease. However, the role of MR in the radiologic workup of gallbladder disease will be determined by more experience with this modality.

Adipose Tissue↗
PubMed1986

Limitation of myocardial ischemia by collateral circulation during sudden controlled coronary artery occlusion in human subjects: a prospective study.

We have shown improvement in collateral filling immediately after sudden controlled coronary occlusion in human subjects undergoing elective coronary angioplasty. It has been suggested but not proved that collateral circulation can limit myocardial ischemia. We prospectively studied 23 patients with isolated left anterior descending (n = 14) or right coronary (n = 9) disease and normal left ventriculograms during elective coronary angioplasty. A second arterial catheter was used for injection of the contralateral artery to assess collateral filling before balloon placement and during coronary occlusion by balloon inflation. Left ventriculography was performed during another inflation. Grading of collateral filling was as follows: 0 = none, 1 = filling of side branches only, 2 = partial filling of the epicardial segment, 3 = complete filling of the epicardial segment. Indexes of myocardial ischemia included percent of the left ventricular perimeter showing new hypocontractility and the sum of ST segment elevation measured on a simultaneous 12-lead electrocardiogram recorded during each inflation. Collateral filling during balloon occlusion and indexes of ischemia were assessed at 30 to 40 sec into inflation. Aortic pressure and heart rate did not correlate with the percent hypocontractile perimeter nor the sum of ST segment elevation. There was a significant correlation between the grade of collateral filling during inflation and both percent hypocontractile perimeter (r = -.85) and the sum of ST segment elevation (r = -.87). Anginal pain occurred in all patients with grade 0 or 1 collateral filling but in only 36% of patients with grade 2 or 3 collaterals. In conclusion, collateral circulation limits myocardial ischemia as assessed by the extent of new ventricular asynergy and electrocardiographic changes during coronary occlusion in patients.

Aged↗
PubMed1986

Cocaine use in persons on methadone maintenance.

Although cocaine use had increased dramatically among all levels of society over the past several years, its use by heroin addicts has existed for decades. To determine whether the prevalence or the pattern of cocaine use changes once an addict enrolls in methadone maintenance, a survey of cocaine use among persons in methadone maintenance therapy was conducted. Of the 613 persons surveyed, 229 (37%) chose to participate, with 33 (14%) considered invalid because of incomplete responses. Of the remaining 196 (86% of the participants), 64 (33%) indicated no cocaine use prior to methadone maintenance, and 132 (67%) reported some prior use. Once treatment had begun, 9 (14%) with no history of prior use admitted to at least one event within the last 6 months, and 55 (86%) reported no use. Of those reporting use prior to methadone maintenance, 41 (31%) stopped usage and 91 (69%) continued. Of the total participants, approximately half used cocaine at least once during methadone maintenance. Among those who used cocaine before and during methadone maintenance, the predominant route of administration was parenteral, 72 (54%) and 46 (51%) participants, respectively. It should be noted that there was a net gain of 17% of patients who stopped using cocaine as a result of entering methadone maintenance. Indices of cocaine use by random urinalysis over the preceding 6 months, for the entire clinic population, revealed only 86 (14%) to 110 (18%) patients to have urine samples positive for cocaine. Although cocaine use decreased on methadone maintenance, its use is still considerable, with the pattern of use differing from the recreational cocaine use in a non-narcotic-dependent population. Random urinalysis for cocaine appears to be an insensitive indication of prevalence of use.

Cocaine↗
PubMed1986

Antihypertensive therapy with indoramin: risk-benefit profile in clinical practice.

In a multicenter, prospective study of step II antihypertensive therapy with indoramin, 1,847 hypertensive patients (773 men and 1,074 women) between the ages of 18 and 70 years were treated by 148 general practitioners. Patients whose blood pressure was inadequately controlled after 4 weeks of therapy with cyclopenthiazide (0.25 to 1.0 mg/day) had indoramin (25 to 200 mg/day) added to their treatment regimen. During cyclopenthiazide treatment, mean (+/- SD) blood pressure decreased from 176/105 +/- 20/7 mm Hg at baseline to 164/98 +/- 21/9 mm Hg (p less than 0.001), and only 447 (24%) patients obtained satisfactory blood pressure control. The addition of indoramin produced a further reduction in mean blood pressure from 169/102 +/- 18/6 to 152/89 +/- 18/8 mm Hg during the first 3 months of treatment (p less than 0.001); this response was maintained for up to 2 years. Satisfactory blood pressure reduction was achieved in 79% of the patients who received indoramin (mean dose, 68 mg/day) plus cyclopenthiazide. Only 25 patients (2%) discontinued indoramin treatment because of nonresponse, and 156 (12%) withdrew because of adverse effects, the most common being sedation, dizziness/giddiness, and headache. These results indicate that indoramin provides safe and effective blood pressure control when used as step II treatment for hypertensive patients who fail to respond to single-agent diuretic therapy.

Adolescent↗
PubMed1986

Neural dynamics of speech and language coding: developmental programs, perceptual grouping, and competition for short-term memory.

A computational theory of how an observer parses a speech stream into context-sensitive language representations is described. It is shown how temporal lists of events can be chunked into unitized representations, how perceptual groupings of past item sublists can be reorganized due to information carried by newly occurring items, and how item information and temporal order information are bound together into context-sensitive codes. These language units are emergent properties due to intercellular interactions among large numbers of nerve cells. The controlling neural networks can arise through simple rules of neuronal development: random growth of connections along spatial gradients, activity-dependent self-similar cell growth, and competition for conserved synaptic sites. Within these networks, a spatial frequency analysis of temporally evolving activity patterns leads to competitive masking of inappropriate list encodings in short term memory. The neurons obey membrane equations undergoing shunting recurrent on-center off-surround interactions. Several design principles are embodied by the networks, such as the sequence masking principle, the long-term memory invariance principle, and the principle of self-similar growth.

Auditory Pathways↗
PubMed1986

Black tongue secondary to methyldopa therapy.

A case of black tongue associated with methyldopa administration is reported. The symptoms disappeared when the medication was discontinued. The possible mechanism is discussed.

Humans↗
PubMed1986

Prayer nodules in Moslem men.

Seven cases of Israeli Moslem men with hyperkeratotic nodular callosities of the legs and forehead are reported. These patients were randomly encountered over a two-year period in our dermatology clinic. The nodules were attributed to repeated trauma to the legs and forehead sustained during Moslem prayer. This article familiarizes the clinician with the morphologic characteristics of these lesions, which may occur in some Moslem men.

Adult↗
PubMed1986

Experience with the Furlow double-reversing Z-plasty for cleft palate repair.

One-hundred and six cases of soft palate closure using the Furlow double-reversing Z-plasty technique have been reported. Most of these patients have been done in the past 2 years. There seem to be a number of worthwhile advantages to this procedure, with few disadvantages or complications. The operation is adaptable for use in early soft palate closure (3 to 6 months) as well as late closure (12 to 14 months), in submucosal clefts, as well as in secondary palatal repair where lengthening and repositioning of the levator muscle is desired. With this type of palatoplasty, the need for raising or shifting large mucoperiosteal flaps from the hard palate has been completely avoided. The operation can be combined with a primary posterior pharyngeal flap if desired, although this is not advised if early palatal closure (3 to 6 months) is used because of a high incidence of sleep apnea. Preliminary speech results are very encouraging.

Child, Preschool↗
PubMed1985

Antihyperlipidemic properties of beta-pyridylcarbinol. A review of preclinical studies.

The available preclinical literature on the antihyperlipidemic properties of beta-pyridylcarbinol is reviewed. Similarities between the pharmacological profiles for beta-pyridylcarbinol and nicotinic acid, and evidence for the metabolic conversion of beta-pyridylcarbinol to nicotinic acid are discussed. Several reviews discussing the antihyperlipidemic effects of beta-pyridylcarbinol (beta-PC, nicotinyl alcohol, Roniacol) and nicotinic acid (NA) have appeared during the last 15 years (1-6). However, continuing clinical interest in the ability of nicotinic acid analogs to reduce plasma lipids indicated that an update and critical evaluation of the preclinical literature on this subject would be of value in order to permit a more complete assessment of the relevance of several animal models to effects in human subjects. The literature reviewed included (a) preclinical studies of beta-PC where it was the sole compound examined; (b) comparative studies of beta-PC and NA; and (c) studies relating to the metabolism of beta-PC. The literature chosen included experiments involving fasted animals, satiated animals, and effects of Triton-induced hyperlipidemia. Data on other pharmacological properties of beta-PC and/or NA that might contribute to antihyperlipidemic efficacy (e.g., fibrinolysis, inhibition of platelet aggregation, erythrocyte membrane changes) were also included where available.

Adipose Tissue↗
PubMed1985

Mr 75,000 protein, a tumor marker in renal adenocarcinoma, reacting with antibodies to a synthetic peptide based on a cloned human endogenous retroviral nucleotide sequence.

Using a rabbit antiserum to a synthetic undecapeptide deduced from a cloned human retroviral gag-gene-related DNA sequence, we found a specific immunohistochemical reaction in all of 42 tested renal cell adenocarcinomas (RCC), while none of 17 similarly tested Wilms' tumors and 65 carcinomas at other sites were positive. The RCC included two cases that presented with distant metastases. It had not been possible to establish the origin of these until immunohistochemical staining revealed this typical reaction. Subsequent renal angiography disclosed the primary. In immunoblotting the antiserum detected an Mr 75,000 protein in RCC tissue, and this reaction was blocked by the undecapeptide. The usefulness of this protein as a tumor marker for RCC is discussed.

Adenocarcinoma↗
PubMed1985

Response of the right ventricle to exercise in isolated mitral stenosis.

Eight patients in sinus rhythm, with varying degrees of isolated mitral stenosis (mitral valve area 0.6 to 1.3 cm2 and total pulmonary vascular resistance 5.0 to 17.5 U-m2), underwent supine rest and symptom-limited exercise radionuclide ventriculography to determine right ventricular (RV) and left ventricular ejection fraction (EF). Cardiac catheterization with hemodynamic measurements at rest and at peak exercise was performed within 24 hours of radionuclide ventriculography. Four of the 8 patients underwent corrective mitral surgery resulting in normal mean pulmonary artery pressures and total pulmonary vascular resistance at rest. These 4 patients had repeat radionuclide ventriculography at rest and during exercise 1 to 2 months after surgery. Preoperatively, all 8 patients had an abnormal exercise RVEF response (mean change +/- standard deviation [SD], -5.0 +/- 4.5%), coincident with an increase in mean pulmonary artery pressure during exercise (mean change, 15 +/- 5.0 mm Hg). The change in RVEF from rest to exercise, corrected for duration of exercise, correlated with peak exercise mean pulmonary artery pressure (r = -0.71, p = 0.05), as well as total pulmonary vascular resistance at rest (r = -0.82, p = 0.02). Postoperatively, all 4 patients who underwent surgical correction showed a normal RVEF response during exercise (mean change +/- SD, +6.8 +/- 4.0%). Thus, in patients with acquired mitral stenosis and no coronary artery disease (1) loading conditions and not contractility are prime determinants of RV exercise response, and (2) an exercise-induced decrease in RVEF may be a sensitive marker for increased total pulmonary vascular resistance and pulmonary hypertension.

Adult↗
PubMed1985

Chondrosarcoma of the head and neck--the value of computed tomography.

Chondrosarcomas of the head and neck represent a small percentage and differ in their treatment and prognosis compared with chondrosarcomas elsewhere. Four different cases of chondrosarcoma are presented. One arose intracranially, two in the jaws, one of which followed irradiation for a retinoblastoma, and the last represents chondrosarcomatous transformation in cervical spine Paget disease which is exceptionally rare. Computer tomography (CT) plays an important role in delineating the extent of the tumor with visualization of bony destruction, associated soft-tissue mass, and calcification, information which is extremely important for surgical and therapeutic planning. CT can be vital in suggesting the best possible site for biopsy which is particularly important in this group of neoplasms where the histological diagnosis may be difficult.

Adult↗
PubMed1985

Clinical investigation in Duchenne dystrophy: V. Use of creatine kinase and pyruvate kinase in carrier detection.

We have determined the value of creatine and pyruvate kinase (CK and PK) in carrier detection by evaluating 811 females in 73 families participating in the Collaborative Investigation of Duchenne Dystrophy. Thirty-nine obligate carriers, 244 normal controls (paternal females), as well as 76 possible carriers and 351 carrier suspects had three CK and PK specimens analyzed at a central laboratory. The CK and PK values varied with age in normals: both fell with age early in life, and CK rose after the fifth decade. Discriminant analysis indicated that the combination of mean CK and PK corrected for age yielded the best data for calculation of carrier probability. Using the best model, only 45% of obligate carriers could be identified at a false-positive rate of 2.5%. Daughters of obligate carriers have a disproportionate decline in CK and PK with age as compared to noncarrier females, suggesting that the rate of carrier detection will be higher in the first two decades. Our low rate of carrier detection, as compared to other studies, may reflect both the age of our obligate carrier population and the use of a control group that is more representative of the carrier population.

Adolescent↗
PubMed1985

Long-term follow-up after intracoronary streptokinase therapy for acute myocardial infarction.

This article describes the effects on patients treated with intracoronary streptokinase during acute myocardial infarction and long-term follow-up. The mortality and the incidence of cardiac events were assessed during a follow-up period of 35 +/- 5 months. Coronary artery bypass grafting was undertaken in 37% of the patients. Hospital mortality was 11%, (n = 8); none of these deaths was due to myocardial rupture. The postdischarge mortality was 10%; three of these patients experienced sudden death. Serial assessment of left ventricular function in 35 patients showed an increase of angiographic ejection fraction prior to intervention from 50 +/- 4% to 58 +/- 12% (p = 0.005) 36 +/- 53 days later. Gated-blood pool imaging after 16 +/- 7 months (n = 35) and 32 +/- 9 months (n = 31) revealed no change in ejection fraction. Angina pectoris recurred in four of the 35 patients. We studied a historical comparison group, that consisted of 66 patients, who were treated at the same institution prior to the advent of intracoronary intervention techniques; this group was followed for 48 +/- 9 months. Baseline clinical and angiographic parameters were comparable in the two groups. Coronary artery bypass grafting was performed in only 18 of these patients. Mortality during hospitalization and postdischarge was not significantly different in the two groups. Ejection fraction decreased significantly in the comparison group from the first to the second evaluation and remained unchanged during the follow-up period. We conclude that no major adverse effects were associated with intracoronary streptokinase infusion over a long follow-up period. This may be related to the high frequency of coronary artery bypass surgery following reperfusion.

Aged↗