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M Cohen

Publications and source records attributed to M Cohen.

At least 469 records · Page 26Linked to original sources
PubMed1994

Thoracoscopic drainage and decortication as definitive treatment for empyema thoracis following penetrating chest injury.

PURPOSE: The purpose of this study is to describe our experience with thoracoscopic drainage and decortication as definitive treatment for empyema thoracis following penetrating chest trauma. METHODS: Over a 9-month period, eight patients at two institutions were treated for empyema thoracis that developed following penetrating chest injury. Seven patients sustained gunshot wounds and one a stab wound. All were treated for hemothorax with a closed tube thoracostomy. Associated injuries included six spinal cord injuries, a liver and diaphragmatic injury, a subclavian injury, and a carotid injury. Each patient subsequently developed an empyema. All patients underwent one thoracoscopic drainage and decortication of the empyema. RESULTS: In all patients, complete resolution of the empyema was achieved with the thoracoscopic technique. Chest tubes were removed a median of 8.5 days after the procedure. Median blood loss was 200 mL. The average duration of the operation was 110 minutes. There were two complications, a persistent air leak and a trapped lung, both treated with thoracoscopic intervention. CONCLUSION: Thoracoscopic drainage and decortication offers an alternative to thoracotomy for definitive therapy of empyema thoracis developing after penetrating chest trauma.

Adolescent↗
PubMed1994

Craniomaxillofacial surgery in the Jehovah's Witness patient.

The reconstruction of severe craniofacial anomalies in patients who will not accept blood transfusions presents a considerable challenge to the craniofacial team. Traditionally, these patients have been refused major reconstructions, receiving no treatment or a highly compromised substitute. A management protocol was developed utilizing preoperative erythropoietin and ferrous sulfate therapy, intraoperative in-line normovolemic hemodilution, and meticulous intraoperative hemostasis which allows us to perform major craniomaxillofacial reconstructions in Jehovah's Witness patients without the use of homologous or predonated autologous blood transfusions.

Adolescent↗
PubMed1994

Single mandibular incisor in a patient with del (18p) anomaly.

A single mandibular incisor and an unusually narrow mandible and tongue were noted in an 8-year-old moderately retarded boy with 18p- (45, XY, der dic (18) (18qter-p11.2::22p 11.2-qter). While a single maxillary incisor, considered a minor feature of holoprosencephaly, was reported in three cases of 18p-, reduction of mandibular incisors has been a very rare finding and has never been noted in similar cases.

Anodontia↗
PubMed1994

Latent autoimmune diabetes mellitus in adults (LADA): the role of antibodies to glutamic acid decarboxylase in diagnosis and prediction of insulin dependency.

Type 1 diabetes mellitus in adults may present in a manner similar to that of Type 2 diabetes but with a late development of insulin dependency. We studied 65 patients who presented with 'adult-onset' diabetes after the age of 30 years. Of these patients, 19 required insulin therapy. The insulin-treated patients were significantly younger, their onset of diabetes was at an earlier age, and their postprandial serum C-peptide levels were lower than those of the non-insulin-treated group. Moreover, the insulin-treated subjects had a higher mean concentration of antibodies to glutamic acid decarboxylase (GAD) (66.8 +/- 10.2 units) than the patients who did not require insulin (9.9 +/- 1.9 units) (p < 0.001) and their frequency of anti-GAD positivity was 73.7% versus 4.3% (p < 0.001). Thus, among patients attending a diabetes clinic, the majority (73.7%) of subjects who presented with diabetes after 30 years of age and who subsequently required therapy with insulin, actually have the islet cell lesion of Type 1 diabetes which progresses at a slower tempo than in children. We conclude that testing for anti-GAD in adult-onset non-obese diabetic patients should be a routine procedure in order to detect latent insulin-dependency at the earliest possible stage, since this assay can assist in the correct classification of diabetes, and more appropriate therapy.

Adult↗
PubMed1994

In utero brain damage: relationship of gestational age to pathological consequences.

The authors examined the brains of two infants in whom episodes of fetal compromise could be accurately correlated with gestational age. A mother who had sustained hypotensive shock at 16 weeks gestation gave birth at 20 weeks to a stillborn infant whose brain showed cystic necrosis of the lenticular nuclei and multifocal polymicrogyria. The brain of a seven-month-old infant born at 33 weeks gestation to a mother who had experienced respiratory arrest during her 28th week showed thalamic and brainstem necrosis accompanied by diffuse white matter gliosis. Review of the literature yielded 10 similar cases. When the insults occurred before 24 weeks of gestation, bilateral pallidal necrosis was a constant feature. Between 26 and 34 weeks, the common finding was thalamic necrosis, often accompanied by brainstem necrosis. These observations should be of assistance in determining the timing of gestational insults, and therefore possible clinical correlations, in prenatal brain damage.

Adult↗
PubMed1994

Modulation of cellular macromolecular synthesis by coronavirus: implication for pathogenesis.

Infection with the murine coronavirus strain JHM decreases cell surface expression of major histocompatibility complex class I antigens. Northern blots showed that JHM virus infection rapidly reduced the level of actin mRNA, whereas the levels of major histocompatibility complex class I and tubulin mRNAs were reduced only slightly. By contrast, the mRNA levels of interleukin 1 beta, colony-stimulating factor 1 receptor, and tumor necrosis factor alpha increased following infection.

Actins↗
PubMed1994

Characterization of the beta 2-microglobulin endocytic pathway in rat proximal tubule cells.

The uptake mechanism(s) of low-molecular-weight proteins by proximal tubule cells remains incompletely characterized. We utilized a biochemical and semiquantitative morphological approach to better characterize the endocytic pathway of an anionic protein, beta 2-microglobulin (beta 2M), in the rat proximal tubule. Indirect immunogold techniques revealed beta 2M was taken up via a classic receptor-mediated endocytic pathway. In vitro biochemical and morphological characterization of iodinated beta 2M and gold-conjugated beta 2M (gold-beta 2M) binding to isolated brush-border membrane vesicles (BBMV) documented specific and quantitatively similar binding interactions of the modified beta 2M with BBMV. Kinetic characterization of the in vivo endocytic pathway of gold-beta 2M was undertaken using microinfusion of individual tubules. beta 2M initially bound at the apical surface, was internalized into subapical coated vesicles and delivered to endosomal-like structures within 5 min, and, finally, was concentrated in lysosomal-like structures within 15 min. This uptake was inhibited by excess unconjugated beta 2M. In addition, we directly showed that uptake did not occur across the basolateral surface. Finally, by passing solubilized BBMV over beta 2M affinity columns we were able to isolate binding activity.

Animals↗
PubMed1994

Combination antithrombotic therapy in unstable rest angina and non-Q-wave infarction in nonprior aspirin users. Primary end points analysis from the ATACS trial. Antithrombotic Therapy in Acute Coronary Syndromes Research Group.

BACKGROUND: The purpose of this study was to compare combination antithrombotic therapy with aspirin plus anticoagulation versus aspirin alone, when added to conventional antianginal therapy in patients with unstable rest angina or non-Q-wave myocardial infarction who were nonprior aspirin users. METHODS AND RESULTS: Two hundred fourteen patients were randomized; 109 were randomized to receive aspirin alone (162.5 mg daily) and 105 to receive a combination of aspirin plus anticoagulation, ie, aspirin 162.5 mg daily plus heparin (activated partial thromboplastin time, two times control) followed by aspirin 162.5 mg daily plus warfarin (international normalized ratio, 2 to 3). Trial therapy was begun by 9.5 +/- 8.8 hours of qualifying pain and was continued for 12 weeks. Primary end points were recurrent angina with ECG changes, myocardial infarction, and/or death. Analysis by intention to treat of primary events at 12 weeks was performed. At 14 days, there was a significant reduction in total ischemic events in the combination group versus aspirin alone (10.5% versus 27%, P = .004). An efficacy analysis of primary events at 12 weeks also revealed a large reduction in total ischemic events in the combination group versus aspirin alone (13% versus 25%, P = .06). Bleeding complications were slightly more common with combination therapy. CONCLUSIONS: In nonprior aspirin users, combination antithrombotic therapy with aspirin plus anticoagulation significantly reduces recurrent ischemic events in the early phase of unstable angina.

Angina, Unstable↗
PubMed1994

Recombinant hirudin for unstable angina pectoris. A multicenter, randomized angiographic trial.

BACKGROUND: Coronary artery thrombosis plays an important pathophysiological role in unstable angina and non-Q-wave myocardial infarction. To date, heparin and thrombolytic therapy has not provided complete or consistent benefit. We hypothesized that recombinant hirudin, a direct thrombin inhibitor, would prevent accumulation of coronary artery thrombus in a manner superior to heparin. METHODS AND RESULTS: Patients with rest ischemic pain, abnormal ECG, and baseline angiogram indicating a > or = 60% stenosis of a culprit coronary artery or saphenous vein graft with visual appearance of thrombus were randomized to one of two different doses of heparin (either a target activated partial thromboplastin time [aPTT] of 65 to 90 or 90 to 110 seconds) or one of four doses of hirudin (0.05, 0.10, 0.20, or 0.30 mg.kg-1.h-1 infusion) in a dose-escalating protocol. After 72 to 120 hours of study drug, a repeat coronary angiogram was obtained, and the paired studies underwent quantitative analysis. The primary end point was change in the average cross-sectional area of the culprit lesion. Other efficacy end points also involved changes in culprit lesion dimensions and TIMI flow grade. Recombinant hirudin led to a dose-dependent elevation of aPTT that appeared to plateau at the 0.2-mg/kg dose. A higher proportion of hirudin-treated patients had their aPTT within a 40-second range (16% heparin versus 71% hirudin, P < .001). Overall, the 116 patients treated with hirudin tended to show more improvement than the 50 patients receiving heparin relative to the primary efficacy variable--the average cross-sectional area (P = .08)--as well as minimal cross-sectional area (P = .028), minimal luminal diameter (P = .029), and percent diameter stenosis (P = .07). CONCLUSIONS: Recombinant hirudin appears to be a promising antithrombotic intervention compared with heparin for inhibition of coronary artery thrombus. Large-scale comparative trials are warranted.

Angina, Unstable↗
PubMed1994

Familial progressive subcortical gliosis.

We report clinical and pathologic findings from two kindreds afflicted with a familial form of progressive subcortical gliosis. The disorder segregated as an autosomal dominant trait. Onset was in the presenium and the course was slowly progressive. Affected individuals initially manifested personality change, degeneration of social ability, disinhibition, psychotic symptoms, memory impairment, or depression. Later, all developed progressive dementia, frequently associated with verbal stereotypy, decreased speech output, echolalia, or manifestations of the human Klüver-Bucy syndrome. Terminal clinical manifestations included profound dementia, frequently with mutism, dysphagia, and extrapyramidal signs. Autopsy of seven end-stage patients revealed generalized cerebral atrophy, predominantly involving the white matter of the frontal and temporal lobes. Microscopically, prominent fibrillary astrocytosis was present in the subcortical white matter and in the subpial and deep layers of the overlying cerebral cortex. These changes were most pronounced in the frontal and temporal lobes, especially in the cingulate gyri and insulae. Mild cortical neuronal loss accompanied the gliosis, but no myelin loss was evident. The claustra and substantia nigra also showed severe astrocytosis and degenerative changes. Amyloid deposits and neuronal cytoskeletal inclusions were absent.

Aged↗
PubMed1994

Detection of myocardial ischemia: value of combined myocardial perfusion and cineangiographic MR imaging.

OBJECTIVE: Established noninvasive methods for assessing myocardial ischemia have limitations that might be overcome by MR imaging. We investigated MR myocardial perfusion imaging and MR ventriculography, before and after dipyridamole-induced stress, to determine whether the superior spatial and temporal resolution of MR imaging has advantages for the evaluation of myocardial ischemia. SUBJECTS AND METHODS: Eighteen patients with symptoms suggestive of myocardial ischemia were examined by use of MR perfusion imaging and MR cineangiography before and during dipyridamole-induced stress. Multiplanar gradient-echo MR cineangiography and cardiac gated fast low-angle shot (turbo-FLASH) MR imaging during injection of gadopentetate dimeglumine were used. Results were compared with findings from perfusion scintigraphy and coronary arteriography. RESULTS: The accuracy of the combination MR technique for detecting myocardial ischemia was similar to that of scintigraphy. No significant difference was found between the MR technique and scintigraphy for detecting segments of myocardium supplied by stenosed coronary arteries (> 70% reduction in diameter, as determined by coronary arteriography). The sensitivity of the combination MR technique for angiographically detecting significant coronary artery narrowing was 92%, and the specificity was 100%. For scintigraphy, the sensitivity was also 92% and the specificity was 100%. CONCLUSION: Initial results indicate that a combination of stress MR myocardial perfusion imaging and MR ventriculography is feasible and that this technique can detect myocardial ischemia with an accuracy similar to that of scintigraphy. This technique may make more complete noninvasive assessment of myocardial ischemia possible.

Adult↗
PubMed1994

Neurological sequelae of the operation "baby lift" airplane disaster.

The aircraft disaster of the first flight of Operation "Baby Lift", which departed from Saigon, Vietnam, April 4, 1975, was survived by 149 orphaned children on their way to adoptive homes in the West. It had 157 passenger fatalities. The aircraft disaster exposed the surviving children to a complex disaster environment in which subatmospheric decompression, hypoxia, and deceleration were experienced, many children suffered a transient unconsciousness. We examined 135 surviving children between 1978 and 1985. The U.S. resident children were examined in the years 1979 to 1982 at an average age of 8 years and 6 months. They displayed the following symptomatology: attention deficit (> 75%), hyperactivity (> 65%), impulse disorder (> 55%), learning disabilities (> 35%), speech and language pathology (> 70%), and soft neurological signs (> 75%). The European children were examined in the years 1983 to 1985. On arrival at the adoptive home, 2 weeks after the accident they displayed the following symptomatology: muscle hypotonia (26%), seizures (2.5%), and regressed developmental milestones (33%). At the time of the diagnostic evaluations (1983 to 1985) the average age was 11 years and 8 months. They displayed the following symptomatology: attention deficit (59%), hyperactivity (52%), impulse disorder (48%), learning disabilities (43%), soft neurological signs (43%), epilepsy (16%), and speech and language pathology (34%). We conclude that a complex disaster environment can cause brain damage in children without prolonged unconsciousness, and that victims of disasters require a thorough evaluation from a multidisciplinary team.

Accidents, Aviation↗
PubMed1994

Treatment of postoperative hypertension after coronary artery bypass surgery. Double-blind comparison of intravenous isradipine and sodium nitroprusside.

BACKGROUND: Hypertension commonly occurs after cardiac surgery and requires therapy to prevent the potentially deleterious effects. METHODS AND RESULTS: After coronary artery bypass graft surgery (CABG), 177 patients with elevated blood pressure > or = 90 mm Hg during the initial 6-hour postsurgical period were selected for this random blinded, parallel study to receive intravenous infusions of either isradipine (n = 90) or sodium nitroprusside (n = 87). Isradipine produced a statistically significant decrease in mean arterial pressure (MAP, delta-23 mmHg) during a 90-minute treatment period. Target MAP (< or = 85 mmHg or a decrease of 10 mmHg, if baseline MAP was between 90 and 95 mmHg) was achieved in 94% of patients 30 minutes after initiation of isradipine infusion (total mean dose, 411 micrograms); target MAP was achieved in 75% of nitroprusside-treated patients (total mean dose, 1708 micrograms). The mean time to control MAP was 18 minutes for isradipine compared with 24 minutes for nitroprusside. Global smoothness in MAP control was graded on a scale of 0 (not controlled) to 5 (excellent). Approximately 76% of isradipine-treated patients received a rating of > or = 3 (mean score, 3.5); 40% of the sodium nitroprusside-treated patients achieved a score of > or = 3 (mean score, 2.0). Both isradipine and nitroprusside produced statistically significant reductions in systolic and diastolic blood pressures, a decrease in systemic vascular resistance, and increases in heart rate, cardiac index, and stroke volume index. Isradipine produced no significant decreases in pulmonary artery occlusion wedge pressure compared with nitroprusside. CONCLUSIONS: Intravenous isradipine was effective and well tolerated in patients with hypertension after CABG and offers an additional therapeutic option to treat patients after cardiac surgery.

Coronary Artery Bypass↗
PubMed1994

Evidence that the Saethre-Chotzen syndrome locus lies between D7S664 and D7S507, by genetic analysis and detection of a microdeletion in a patient.

The locus for Saethre-Chotzen syndrome, a common autosomal dominant disorder of craniosynostosis and digital anomalies, was previously mapped to chromosome 7p between D7S513 and D7S516. We used linkage and haplotype analyses to narrow the disease locus to an 8-cM region between D7S664 and D7S507. The tightest linkage was to locus D7S664 (Z = 7.16, theta = .00). Chromosomes from a Saethre-Chotzen syndrome patient with t(2;7) (p23;p22) were used for in situ hybridization with YAC clones containing D7S664 and D7S507. The D7S664 locus was found to lie distal to the 7p22 breakpoint, and the D7S507 locus was deleted from the translocation chromosomes. These genetic and physical mapping data independently show that the disease locus resides in this interval.

Acrocephalosyndactylia↗
PubMed1994

Future shock: trauma in the managed care era.

This study examines the effects of managed care on the treatment of 1724 trauma patients seen over a 2-year period at an urban Level I trauma center. Fifty-one per cent of all trauma patients were insured. Managed care plans represented 42 per cent of the insurance coverage overall, increasing from 39 per cent in the first year to 45 per cent in the second. All treatment was provided by the receiving general surgery trauma team and was rendered independent of insurance status. Eighty per cent of patients completed their hospitalization at the trauma center. Clinical outcome, transfer rates, and mortality were similar regardless of insurance type. We conclude that managed care plans represent a significant and increasing portion of the insurance coverage of trauma patients, and propose that national guidelines should be developed to guarantee quality and continuity of trauma care.

Forecasting↗