Biomedical subjects
Publications and source records attributed to R Doshi.
Two patients are described with proximal muscle weakness and electromyographic evidence of a myopathic process. In both, discrete carcinomatous metastatic deposits were found in proximal muscles. The possible clinical implications are discussed.
This report concerns morphologic findings in two middle-aged women, who died of sporadic adult neuronal ceroid-lipofuscinosis (NCL) and whose brains were studied histologically, by electron microscopy and by pigmentoarchitectonic techniques. In addition, the brain of a 35-year-old woman, who died of familial protracted juvenile NCL, was also investigated using pigmentoarchitectonic methods. Clinical, light and electron microscopic findings were compatible with the above-mentioned diagnosis. Pigmentoarchitectural analysis of homotypical isocortex in these three brains revealed (1) loss of pigment-laden stellate cells in layer II, (2) axonal enlargements of layer IIIab-pyramidal cells, and (3) considerable cell loss in layer Va. The changes were more pronounced in the brain affected by protracted juvenile NCL than in the two brains affected by adult NCL. The study emphasizes the value of the pigmentoarchitectonic technique, both in diagnostic neuropathology and in ascertaining patients afflicted with adult NCL. The ultrastructure of the lipopigments showed a motley spectrum of membrane formation such as curvilinear, fingerprint, or straight membranes and was less granular than regular senile lipofuscin.
Plasma renin activity (PRA) was estimated in 23 patients during the 1st week after a subarachnoid hemorrhage (SAH) and in a control group of 6 postlaminectomy patients. Patients with altered levels of consciousness and neurological deficits had significantly higher levels of PRA than did patients who were alert and neurologically intact. The SAH patients were divided into three groups: (a) low renin (13 patients with a PRA of less than 1.77 pmol/ml/hour), (b) normal renin (2 patients with normal renin levels), and (c) high renin (8 patients with a PRA of greater than 2.5 pmol/ml/hour). Patients with high renin levels had a significantly higher incidence of morbidity and mortality than did those with low renin levels. There were also higher levels of urinary catecholamines in the high renin group of patients. The combination of altered consciousness, high levels of urinary catecholamines, particularly adrenaline; and a high PRA in the 1st week after a SAH indicates a poor prognosis.
The hypothalamus and myocardium of 54 patients (27 males and 27 females, age range 12 to 73 years) who died after subarachnoid hemorrhage (SAH) were examined histologically. In 42 patients, hypothalamic and myocardial lesions were found; in seven, hypothalamic lesions only; and in five, no hypothalamic nor myocardial lesions. A similar examination was performed on a control group of 25 patients (12 males and 13 females, age range 17 to 70 years) who had died from a variety of causes, all producing raised intracranial pressure. In these, no lesions were found in either the hypothalamus or the myocardium. The age of the patient, the site of the vascular pathology, and whether an operation was performed appeared to have no effect on the occurrence of hypothalamic and heart lesions; however, there was a correlation between these lesions, progressive neurological deterioration, and varying pulse rates and blood pressures. This study produces further evidence of the involvement of the autonomic nervous system in some of the deleterious effects of SAH, and a suggestion is made as to possible treatment.
Two children are described with primary hypogammaglobulinaemia and encephalitis associated with echovirus infection. One also developed a condition resembling dermatomyositis which improved after he was given infusions of plasma containing antibody to the echovirus. Although both died of their encephalitis, the course of the brain disease in one of them may have been prolonged by treatment with specific antibody. These cases, together with another briefly mentioned case in an adult with congenital hypogammaglobulinaemia and echovirus infection, indicate that these patients are particularly susceptible to echoviruses.
The clinical and histological features of two cases of giant cell tumor of the sphenoid bone are described. Both presented with similar symptoms and signs, comparable to previously described cases. The problems in histological differential diagnosis are discussed and radiotherapy as the treatment of choice is suggested.
The hypothalamus and myocardium of 12 patients who had died after a subarachnoid haemorrhage, and of six patients who had died from other intracranial pathology were examined. Only in the patients who had died from subarachnoid haemorrhage were histological lesions found in both the hypothalamus and myocardium. The possible significance of these findings is discussed with particular reference to the sympathetic nervous system.
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Studies in the morphology, histochemistry, and ultrastructure of the cerebellum, with special reference to the Purkinje cell dendrites, have been undertaken in eight cases of gargoylism. The results suggest that the demonstration of ovoid swellings of the Purkinje cell dendrites by the Cajal method for the cerebellum, together with certain histochemical findings, may enable a diagnosis of mucopolysaccharidosis to be made. Possible mechanisms for the formation of these swellings are briefly discussed.
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This manuscript describes a new method, validated in in vitro models, for quantitating volume flow rate across an orifice with Doppler color flow mapping. Flow through a narrowed orifice is characterized by the convergence of radial streamlines proximal to the orifice. In this color Doppler method, one or more isovelocity surface areas (PISA), delineated by blue and red aliasing velocity interfaces, can be identified proximal to the narrowed orifice. Volume flow rate (in milliliters per second) can then be calculated as PISA (in square centimeters) multiplied by the isovelocity of the PISA (in centimeters per second). Doppler color flow mapping was performed in in vitro models of constant and pulsatile flow through an orifice in a wall. The first proximal isovelocity surface area, with an isovelocity corresponding to the aliasing velocity, that is, one half the Nyquist sampling limit, could be identified as a blue and red color interface proximal to the orifice. Over a range of circular orifice diameters from 3 mm to 16 mm and flow rates from 0.5 to 18.7 L/min, the proximal isovelocity surface area could be imaged in two planes. This PISA was best described by a hemielliptic mathematical model with two different radii measured from long-axis and short-axis views. In the constant flow model, volume flow rate calculated from the Doppler PISA correlated well with actual volume flow rate measured simultaneously with a cylinder and stopwatch (r = 0.98, p less than 0.001, standard error of the estimate [SEE] = 0.36 L/min). In the pulsatile flow model, with jet velocities ranging from 2.6 to 7.7 m/sec and flow volume ranging from 1.0 to 10.3 L/min, calculated volume flow rate also demonstrated an excellent correlation with actual volume flow rate (r = 0.99, p less than 0.001, SEE = 0.53 L/min). Findings from these in vitro models suggest that quantification of the proximal isovelocity surface area by Doppler color flow mapping appears to be a promising technique for estimating volume flow rate across a narrowed orifice. This new color Doppler flow method may have advantages over previous Doppler methods in estimating volume flow rate in various clinical situations, for example, valvular regurgitation and shunt lesions.
Malignant lymphoma initially presenting with symptoms and signs of spinal cord compression are a rare occurrence. We present 20 cases of spinal epidural lymphoma first diagnosed on laminectomy biopsy specimens with a review of clinical data and histology, as well as an immunohistochemical study to determine the immunophenotype of these lymphomas. Eighteen cases were typed as B cell lymphomas, 2 as T cell lymphomas.