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Biomedical subjects

A Shah

Publications and source records attributed to A Shah.

At least 271 records · Page 15Linked to original sources
PubMed1994

MR volume segmentation of gray matter and white matter using manual thresholding: dependence on image brightness.

PURPOSE: To describe a quantitative MR imaging segmentation method for determination of the volume of cerebrospinal fluid, gray matter, and white matter in living human brain, and to determine the method's reliability. METHODS: We developed a computer method that allows rapid, user-friendly determination of cerebrospinal fluid, gray matter, and white matter volumes in a reliable manner, both globally and regionally. This method was applied to a large control population (N = 57). RESULTS: Initially, image brightness had a strong correlation with the gray-white ratio (r = .78). Bright images tended to overestimate, dim images to underestimate gray matter volumes. This artifact was corrected for by offsetting each image to an approximately equal brightness. After brightness correction, gray-white ratio was correlated with age (r = -.35). The age-dependent gray-white ratio was similar to that for the same age range in a prior neuropathology report. Interrater reliability was high (.93 intraclass correlation coefficient). CONCLUSIONS: The method described here for gray matter, white matter, and cerebrospinal fluid volume calculation is reliable and valid. A correction method for an artifact related to image brightness was developed.

Adult↗
PubMed1993

Serodiagnostic efficiency of phospholipid associated protein of Mycobacterium tuberculosis H37Rv.

The phospholipid-associated protein (55-67 kDa) fraction of Mycobacterium tuberculosis H37Rv was purified as the DE-V protein fraction. This DE-V fraction was used for diagnosis of tuberculosis by enzyme-linked immunosorbent assay (ELISA), detecting IgG antibody in sera collected from different categories of tuberculosis patients, i.e. with acid fast bacilli (AFB) culture-positive pulmonary tuberculosis, with AFB culture-negative, but radiologically suspected, pulmonary tuberculosis, extrapulmonary tuberculosis, and control groups of patients suffering from diseases other than tuberculosis (asthma and/or rhinitis, lepromatous leprosy) as well as from healthy volunteers. Encouraging operational ELISA validity could be achieved with 93% sensitivity, 100% specificity, 97% efficiency, 100% positive predictivity and 95% negative predictability even among the extrapulmonary and suspected pulmonary tuberculosis patients. The above assay was insensitive but with 100% specificity among control group of patients suffering from diseases other than tuberculosis. The DE-V protein fraction was associated with phosphatidyl inositol and phosphatidyl inositol mannosides. The dissociation of phospholipid-protein complex decreased ELISA specificity. ELISA reactivity of the DE-V fraction appeared to be thermostable; thus, it may have serodiagnostic utility in developing countries.

Antibodies, Bacterial↗
PubMed1993

High dose Nutrizym 22 in cystic fibrosis.

New high dose pancreatic enzyme preparations could be potentially helpful to cystic fibrosis (CF) patients. The purpose of this study was to compare the efficacy of the new high dose pancreatic enzyme preparation, Nutrizym 22 with the standard preparation Nutrizym GR. Twenty-five CF children (aged 7-16 years) entered the study and 22 completed it; 3 did not, due to non-compliance. All were taking Nutrizym GR for at least 2 weeks before entering the study. A randomised double blind, crossover method using standard Nutrizym GR or double strength Nutrizym 22 capsules was carried out over two consecutive 14-day periods. Crossover analyses of variance showed no statistically significant differences in actual weight gain, appetite, abdominal pain, stool consistency or faecal fat during the prestudy and study periods. It is concluded that half the capsule numbers of the high strength preparation are just as effective as the standard capsule dosage.

Adolescent↗
PubMed1993

Immunopharmacologic therapy in myasthenia gravis.

Immunotherapy is frequently employed in treatment of patients with myasthenia gravis. Different regimens are not based entirely on controlled or comparative studies. There are few clear guidelines for choosing a particular immunomodulating agent and timing of its introduction. In this article, we have tried to summarize known information about the immunopharmacologic agents used for the treatment of patients with myasthenia gravis.

Adjuvants, Immunologic↗
PubMed1993

Hemodynamic responses to penetrating spinal cord injuries.

Although the hemodynamic response to blunt spinal cord injury has been well described, much less is known about the responses to penetrating spinal cord injuries. In order to elucidate any differences, we reviewed the last 75 patients treated over the past 12 years with penetrating spinal cord injuries. There were 67 men and eight women; the mean age was 26.2 years (range, 15-59 years); 73 patients suffered 120 gunshot wounds; one patient was injured with an ice pick; one was stabbed twice. The offending missile causing spinal cord injury entered the neck in 24%, the thorax in 56%, and the abdomen in 20%. Nine patients (12%) were complete quadriplegics and 49 patients (65%) were complete paraplegics; 69 patients (92%) had no rectal tone; 17 patients (22%) had incomplete injuries. Despite the high proportion of complete spinal injury (78%), only 18 patients (24%) were hypotensive in the field. Five additional patients became hypotensive in the ED. Of the 23 patients with hypotension, 18 (74%) had significant blood loss to explain their low blood pressure. The mean HR was 100 beats/minute in the field (range, 50-130 beats/minute) and 90 beats/minute in the ED. Only five patients (7%) demonstrated the classic presentation of neurogenic shock (hypotension and bradycardia). This classic presentation of neurogenic shock is rare following penetrating spinal cord injury. Despite evidence of a complete spinal cord injury on initial physical examination, hypotension is usually secondary to blood loss in these patients. A careful search for sources of blood loss is mandatory before ascribing hypotension to spinal injury.

Adolescent↗
PubMed1993

Deficiencies in school readiness skills of children with sickle cell anemia: a preliminary report.

Patients with sickle cell anemia often express myriad clinical signs and symptoms that affect their life-style and academic performance. Certain psychoeducational and psychosocial factors have been shown to influence the academic achievement of older patients with sickle cell anemia. However, studies evaluating the school readiness skills of younger children have not been published. To determine whether sickle cell anemia delays preschool development in children aged 4 to 6 years, we studied 10 affected children and 10 normal subjects matched for age, sex, and race. School readiness was evaluated by the Pediatric Examination of Educational Readiness (PEER), which assess a child's performance in areas of developmental attainment such as visual input, verbal output, and short-term memory. The presence of associated movements (minor neurologic signs) and other areas of behavior such as selective attention, activity level, adaptive behavior, and processing efficiency are also observed. The children with sickle cell anemia scored significantly lower than their normal counterparts in several parameters of the PEER. The McCarthy Scales of Children's Abilities, a standardized psychometric test, showed that these children with sickle cell anemia were within the normal range of intelligence. Magnetic resonance imaging done on three children with sickle cell anemia who scored lowest on the PEER revealed no cerebrovascular infarcts. These preliminary studies demonstrate significant differences in school readiness skills between children with sickle cell anemia and normal subjects.

Anemia, Sickle Cell↗
PubMed1993

Why do autistic individuals show superior performance on the block design task?

Systematic variations of the block design task were given to 20 autistic, 33 normal and 12 mildly retarded subjects. Designs were contrasted which were either "whole" or segmented, rotated or unrotated, and which did or did not contain obliques. Only segmentation, but neither of the spatial orientation factors, revealed a significant group difference. Autistic subjects, regardless of age and ability, performed better than controls when presented with unsegmented designs. This result suggests that they need less of the normally required effort to segment a gestalt, and thus supports the hypothesis of weak central coherence as a characteristic of information processing in autism.

Adolescent↗
PubMed1993

Extrinsic nonvalvular mitral obstruction due to large epicardial hematoma.

A case of extrinsic nonvalvular mitral obstruction due to a large epicardial hematoma in a patient with rheumatoid constrictive pericarditis is described. The patient had longstanding rheumatoid arthritis and a mitral diastolic murmur developed. Mitral obstruction was confirmed by a hemodynamic study. Coronary angiography and left ventricular angiography showed severely diseased coronary arteries and a distorted left ventricular cavity. Autopsy demonstrated rheumatoid arthritis, a normal mitral valve, thickened pericardium, and epicardial hematoma surrounding both ventricles at the atrioventricular junctional level.

Arthritis, Rheumatoid↗
PubMed1993

Diagnosis of multi-infarct dementia: predictive value of clinical criteria.

Clinical and neuroimaging features that best discriminated a multi-infarct dementia diagnosis from a diagnosis of Alzheimer's disease were retrospectively reviewed for 192 patients of a university-based dementia diagnostic clinic. Only a subset of features usually ascribed to multi-infarct dementia actually distinguished that diagnosis from the diagnosis of Alzheimer's disease.

Aged↗
PubMed1993

9 Knee arthroplasties for sickle cell disease.

Sickle cell disease sometimes presents with knee arthropathy secondary to osteonecrosis. We report our experience with 9 total knee arthroplasties in 5 patients. The joint fluid, synovium, capsule, and excised bones were sent for culture. Tissue cultures from 5 knees grew organisms. The outcome was: 6 excellent, 1 good, 1 satisfactory, and 1 poor. Infection in 1 case led to removal of the prosthesis and subsequent arthrodesis. 1 patient had persistent peroneal nerve palsy. There were no hematological complications. We suggest that osteonecrosis in sickle cell disease should be considered septic.

Adolescent↗
PubMed1993

False aneurysm complicating closed femoral fracture in a child.

False aneurysms are a recognized but rare complication of closed fractures. The authors report the case of a false aneurysm of the superficial femoral artery complicating a closed transverse fracture of the femoral shaft in a child treated with skeletal traction. The literature of this entity is reviewed.

Aneurysm, False↗
PubMed1993

Coronary collateral circulation in the transplanted heart.

BACKGROUND: The concept that coronary collateral (CC) circulation can develop in cardiac transplant recipients (CTR) is controversial. Indeed, a decreased occurrence of CC in CTR has been previously reported. METHODS AND RESULTS: We reviewed 102 coronary angiograms in 73 CTR to evaluate the presence and significance of CC in denervated human hearts. These angiograms were compared with angiograms of 70 nontransplanted patients. Twenty-six CTR who had undergone at least two coronary angiograms, thus allowing comparative evaluations, form the basis for this study. Angiograms were analyzed using a modification of CC classification (Rentrop et al) from grade 0 for complete absence to grade 4 representing mature collateral with clear filling of epicardial vessels. Coronary artery disease was classified according to the scheme reported by Gao et al. For the purpose of this study, all type A lesions were grouped as large vessel disease (LVD), and types B1, B2, and C were collectively grouped as small vessel (epicardial) disease (SVD). The presence of CC circulation in all 73 CTR was grade 0, 7 (10%); grade 1, 41 (56%); grade 2, 33 (45%); grade 3, 30 (41%); and grade 4, 5 (7%). However, in control nontransplanted subjects grades 0, 1, 2, 3, and 4 were found in 47 (67%), 22 (31%), 4 (6%), 11 (15%), and 16 (20%) patients, respectively. The presence of mature collaterals (grade 4) in both groups were associated with type A lesions and was frequent in nontransplanted hearts. In contrast, grade 2 and grade 3 vascular channels probably representing CC with "myocardial blush" was more frequent in CTR and was mostly associated with small vessel coronary arteriopathy. CONCLUSIONS: These results suggest the presence of atypical CC in patients with cardiac allograft arteriopathy. It is speculated that this atypical form of CC with "blush pattern" may represent an angiogenic response to microvascular ischemia due to allograft coronary arteriopathy.

Adult↗