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Biomedical subjects

J M Cohen

Publications and source records attributed to J M Cohen.

At least 73 records · Page 4Linked to original sources
PubMed1991

A new influenza surveillance system in France: the Ile-de-France "GROG". 2. Validity of indicators (1984-1989).

The evaluation of the validity of the GROG's indicators is based on the first five years of activity, four of which being epidemic ones. A virological criterion for identifying epidemics is used as the gold standard. For each non-specific indicator, the ratio of epidemic weeks to non-epidemic weeks is outlined. Therefore we can define four epidemic situations in relation with the strains circulating and the non-specific indicators. Influenza A epidemics, which are known as a mortality problem can also be described according to its impact upon morbidity. As a result, it is possible to set up a sensitive and specific surveillance system for early detection of influenza epidemics. This objective is achieved by combining both the weekly collection of virological data as well as the collection of other available indicators either in routine practice or as provided by a network of sentinel practitioners. Such detection can pave the way for an improvement in preventive measures against the harmful effects on health of influenza epidemics.

Antiviral Agents↗
PubMed1991

Magnetic resonance imaging of temporomandibular joint after surgical treatment of internal derangement.

Sagittal and coronal surface coil magnetic resonance imaging was performed on 21 patients who about 2 years earlier had surgery for temporomandibular joint internal derangement. Surgical procedure included disk repositioning (23 joints) and diskectomy (seven joints). At the time of reimaging, 20 joints showed recurrence of pain and 10 joints were asymptomatic. Extensive fibrous tissue was seen in the joint space and in the joint capsule in 13 of the 20 painful joints, whereas minimal fibrous tissue in the lateral capsule wall was seen in 3 of the 10 nonpainful joints. Fibrous tissue was surgically confirmed in 10 of the painful joints. Disk displacement was seen in 11 of the 23 joints that had surgical disk repositioning. Disk displacement was seen in both painful (9/17) and nonpainful joints (2/6). It was concluded that magnetic resonance imaging is an excellent method for postoperative imaging of the temporomandibular joint and that attention should be directed to the presence or absence and extension of the fibrous tissue in the joint space and in the joint capsule.

Adolescent↗
PubMed1991

Comparison of reading speed in normal observers through different forms of equivalent power low vision devices.

Compensation at near for vision loss can be achieved using a variety of equivalent forms of low vision magnifiers. Each has inherent advantages and disadvantages in terms of field, working distance, etc. We compared the reading speed of 60 trained, normal observers with 4 commonly prescribed types of low vision devices of +12 D equivalent power (spectacles, hand magnifier, stand magnifier, and telemicroscope) to their normal reading speed. Although there was individual variance in performance, reading speed with all the devices was generally within 20% of normal reading speed. Implications are that in terms of differences in reading speed for normals, the form of the low vision device is not as significant as acquiring proficiency in the use of the selected device.

Adult↗
PubMed1991

Reading speed through different equivalent power low vision devices with identical field of view.

Adequate reading speed is one of the criteria low vision patients may use to assist them when they are comparing and selecting equivalent power low vision devices. Inherently, various optical devices of equivalent power will produce different fields of view. We compared the reading speed of 32 trained, normal observers with 4 commonly prescribed types of low vision devices of +12 D equivalent power (spectacles, hand magnifier, stand magnifier, and telemicroscope) which were modified to provide nearly identical fields of view. Our results show that only the reading speed obtained with the telemicroscope was significantly different from those of the other systems (p less than 0.01). Implications are that the field of view provided by a low vision device is the primary parameter limiting reading speed of equivalent power devices.

Adult↗
PubMed1991

Propafenone-induced torsade de pointes: cross-reactivity with quinidine.

A 77-year-old female with new onset atrial fibrillation occurring in the absence of structural heart disease developed torsade de pointes during therapy with quinidine bisulfate 500 mg orally every 8 hours. Ten days after quinidine therapy had been discontinued she developed torsade de pointes while receiving propafenone 300 mg orally every 8 hours. This case demonstrates that propafenone may be associated with torsade de pointes and suggests a cross-reactivity between this effect and prior occurrence of torsade de pointes on Class IA antiarrhythmic drug therapy.

Aged↗
PubMed1991

Modification of common low vision devices for uncommon needs.

Creativity in the field of low vision is certainly a necessary requisite when trying to solve a patient's individual needs. Four different categories of low vision devices--hand magnifier, stand magnifier, telescope, and absorptive lens--were modified initially to meet a particular patient's requirement(s). The devices modified were: 1) a +28 aspheric hand magnifier; 2) a magnetized stand magnifier to assist patients in stabilizing a stand magnifier; 3) a focusable telescope held on a gooseneck stand; and 4) a flip-up frame for the Corning CPF series of lenses. These modifications could be of benefit to other patients.

Equipment Design↗
PubMed1990

Lipid degeneration in a pheochromocytoma histologically mimicking an adrenal cortical tumor.

A recurrent adrenal pheochromocytoma is reported in an 18-year-old woman with a family history of multiple endocrine neoplasia type IIA. The tumor was noteworthy for the presence of numerous fine intracytoplasmic lipid droplets confirmed by fat stain. Immunohistochemical studies revealed cytoplasmic positivity for chromogranin and neuron-specific enolase typical of pheochromocytoma. Electron microscopy demonstrated dense-core neurosecretory granules, in addition to the cytoplasmic lipid vacuoles. The presence of lipid within an adrenal pheochromocytoma is rare and, to our knowledge, has been documented in only one previous case report in the literature.

Adolescent↗
PubMed1989

A new influenza surveillance system in France: the Ile-de-France "GROG". 1. Principles and methodology.

The aims of influenza surveillance have changed over the years. The early detection of epidemics is essential for practical decisions on vaccine development, strategy of vaccine prophylaxis, chemoprophylaxis or chemotherapy. A new surveillance system is presented which combines the classical specific data related to the isolations, direct detection of virus as well as serological findings, with non-specific indices. The rationale for definition and elaboration of such indices is discussed: selected parameters deal with medical activity of a panel of sentinel doctors (general practitioners and pediatricians), notifications of diagnosed acute respiratory viral infections, measure of emergency doctors activity, absence from work (as seen by physicians, insurance agencies or industrial personnel), selected drug prescription and consumption, hospital admissions. The sentinel physicians also cooperate in taking samples from cases, thereby extending the field of specific surveillance since they have contact with standard cases of the disease and not only hospitalized patients. A weekly comparison of time variations of specific and non-specific indices should permit a reliable evaluation of the epidemic situation and therefore be of great help for practical decisions. The system has operated since 1984, and the initial hypothesis of the sensitivity of some of the indices has already been verified.

Disease Outbreaks↗
PubMed1989

Ileal pouch vaginal fistulas: incidence, etiology, and management.

Some of the initial problems associated with the ileoanal reservoir have been solved. In their place, other complications have been recognized. Among these, the ileal pouch vaginal fistula stands out as a recently recognized difficult management problem. This multicenter study was undertaken to gain insight into the causes for, and treatment of, pouch vaginal fistulas. Cases were gathered from 11 surgical practices throughout North America, in which the ileoanal reservoir procedure is frequently performed. Overall, 304 females had undergone ileoanal reservoir procedures by these surgical groups. Twenty-one patients developed 22 pouch vaginal fistulas for an overall incidence of 6.9 percent. Five additional patients with pouch vaginal fistulas, whose restorative proctocolectomies were done elsewhere, were referred to these surgeons for treatment. The courses of these 26 patients form the basis of this report. This study details the risk factors which predispose in the development of a pouch vaginal fistula, as well as the various treatment options available.

Adolescent↗
PubMed1989

Prevalence of lumbosacral intervertebral disk abnormalities on MR images in pregnant and asymptomatic nonpregnant women.

The prevalence of lumbosacral intervertebral disk bulge and herniation on sagittal magnetic resonance (MR) images was determined in 45 pregnant subjects and 41 asymptomatic nonpregnant women of childbearing age. MR technique differed for the pregnant and nonpregnant groups. Fifty-three percent of pregnant and 54% of nonpregnant women had an abnormal disk (bulge or herniation) at one or more levels (L3-4, L4-5, or L5-S1). The difference was not statistically significant. There was also no significant difference in the distribution of outcomes among the 45 pregnant subjects, 17 parous nonpregnant women, and 24 nulliparous women. The results suggest that lumbosacral disk bulges or herniations are common in women of childbearing age, whether pregnant or not, and that, contrary to an earlier report, pregnant women do not have an increased prevalence of disk abnormalities.

Adult↗
PubMed1989

Transient abdominal granulomas in children.

Space-occupying liver lesions in febrile patients are usually caused by tumor or infection and other causes are seldom encountered. In five patients age 20 months to 12 years who were evaluated for fever of unknown origin, imaging studies revealed hepatic nodules consisting of transient, sterile granulomas for which no cause could be determined. Stellate architecture histologically supported clinical evidence of subacute bacterial infection. Imaging modalities included: 99Tc-sulfur colloid (n = 2) and 67Ga (n = 2) scintigraphy; ultrasound (n = 5); computed tomography (n = 4); and magnetic resonance imaging (n = 2). Peripheral low density, as revealed by computed tomography in one and hyperintense halos on magnetic resonance imaging of another patient are both considered predictive for neoplastic disease but were associated with granulomas. The differential diagnosis of macroscopic liver lesions seen on imaging studies in febrile children should include the possibility of transient, idiopathic granulomas.

Child↗
PubMed1988

Characterization and identification of substances isolated from dialyzer extracts.

The organic phase of dialyzer dried extracts obtained from Cuprophan hollow fiber and polyacrylonitrile AN 69 parallel-plate dialyzers, all sterilized by ethylene oxide, were submitted to light and polarized light microscopy, infrared (IR) spectrophotometry, and gas chromatography coupled with mass spectrometry. Colorless polygonal (approximately 5 X 20 micron) and needle-like (approximately 3 X 50 micron) crystals were found in great quantity on microscopy examination. IR spectrophotometry of the crystals embedded in potassium bromide disc showed specific spectra in the 1400-800 cm-1 wave number range and typical peaks on wave number assigned for hydroxy or amine (3420 cm-1), aromatic hydrogen (3060 cm-1), methyl, methylenic, or methenyl (2960-2860 cm-1), and carbonyl (1715 cm-1) groups can be demonstrated. Seven peaks were detected on gas chromatography of the organic solution containing crystals. Fatty acids and undefined compounds could originate from the dialyzer. Phtalates may leach from blood tubing, used in the rinsing procedure, and BHT is a stabilizer of ethyl ether used as solvent. These compounds could also originate from the dialyzer since phtalates are widely used as a plasticizer and BHT an antioxidant for various polymers.

Acrylic Resins↗
PubMed1987

Teardrop bladder: demonstration by magnetic resonance imaging.

Teardrop deformity of the urinary bladder and ureteral deviation may be caused by iliopsoas hypertrophy. Magnetic resonance imaging (MRI) findings in such a case are described, and the potential advantages of MRI in evaluating the pelvis are discussed.

Adult↗
PubMed1986

Pattern of urinary symptoms in patients with metastatic bladder cancer.

In an attempt to assess the development or progression of symptoms in patients with metastatic bladder cancer we reviewed 41 patients who died of the disease but who did not undergo cystectomy. Therapy for the local tumor was used when indicated. Of the 41 patients 9 experienced worsening of symptoms, while the others were either stable or improved. Only 1 of 10 asymptomatic patients suffered symptoms during the course of the illness.

Adult↗
PubMed1986

Assessment of pericardial constraint: the relation between right ventricular filling pressure and pericardial pressure measured after pericardiocentesis.

Experimental studies have shown that right ventricular filling pressure (that is, intracavitary diastolic pressure) approximates pericardial surface pressure but, in many patients after removal of pericardial effusion, right ventricular filling pressure has been found to markedly exceed pericardial pressure recorded by an open catheter. The aim of this study was to determine whether this apparent contradiction was related to the technique of pericardial pressure measurement. Nine patients with chronic pericardial effusion were studied and, although these pressures diverged to varying degrees in individual patients, the previous observation was confirmed in that, although initially similar, right ventricular filling pressure and pericardial pressure (measured by means of an open catheter) tended to diverge during removal of the effusate; when the evacuation was as complete as possible pericardial pressure was 2.1 +/- 1.0 (mean +/- SE), while right ventricular filling pressure was 8.7 +/- 1.7 mm Hg (p less than 0.01). In six open chest, anesthetized, volume-loaded dogs with pericardial effusion (50 ml), right ventricular filling pressure and pericardial pressures measured with both open catheter and flat balloon were all equal. With decreasing volume of pericardial fluid, right ventricular filling pressure and pericardial pressure (by catheter) diverged as had been observed in patients. However, pericardial pressure (balloon) continued to be equal to right ventricular filling pressure. (With 0 ml in the pericardium, right ventricular filling pressure = 12.9 +/- 0.9 mm Hg, pericardial pressure [catheter] = 1.4 +/- 1.9 mm Hg and pericardial pressure [balloon] = 12.4 +/- 1.5 mm Hg.) Thus, these observations support the use of right ventricular filling pressure as an estimate of pericardial constraint in patients.

Adult↗
PubMed1986

Arteriovenous malformations of the extremities: MR imaging.

Eight patients with angiographically proved arteriovenous malformations (AVMs) of the extremities (seven congenital, one posttraumatic) were evaluated with magnetic resonance (MR) imaging using a 0.35-T superconducting system and spin-echo pulse sequences. Congenital AVMs appeared as accumulations of dilated tortuous blood vessels infiltrating the involved muscles. A posttraumatic acquired AVM of the shoulder consisted of a large feeding artery associated with a pseudoaneurysm and a soft-tissue mass. MR imaging allowed precise anatomic localization and provided details concerning the size and extent of the AVMs. The relationship of AVMs to specific muscle groups, bones, and vascular structures could be accurately determined. Although major feeding and draining vessels were identified, the exact arteries and veins supplying and draining the AVM could not be ascertained. Images obtained in the transverse plane consistently yielded the most useful information. MR imaging and angiography may be complementary techniques in the initial evaluation, follow-up, and treatment planning of AVMs of the extremities.

Adolescent↗
PubMed1986

Pelvic masses in pregnant patients: MR and US imaging.

Sixteen pregnant patients with pelvic masses detected with ultrasound (US) were studied with magnetic resonance (MR) imaging at 0.35 T. Two patients were in their first trimester, eight in the second, and six in the last. On MR images, 34 masses were seen, including 19 uterine leiomyomas. With US, 20 masses were detected. All masses not seen with US were leiomyomas. Only 20 masses (in 11 patients) were removed for histologic study. In nine cases, MR imaging and US provided similar information on the origin, extent, and type of mass. In seven patients, MR imaging contributed additional information. MR imaging depicted more leiomyomas than US in three patients. In another case, MR images showed that a mass depicted with US was actually a loop of bowel. MR images allowed differentiation between a solid soft-tissue mass and a hemorrhagic fluid-containing mass, correctly depicted the presence of an abdominal pregnancy, and allowed evaluation of the parametrium for spread of cervical carcinoma.

Female↗