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Biomedical subjects

M R Patel

Publications and source records attributed to M R Patel.

At least 91 records · Page 5Linked to original sources
PubMed1985

Tenosynovial osteochondromatosis of the extensor tendon of a digit: case report and review of the literature.

Extra-articular tenosynovial osteochondromatosis in the hand rarely occurs. A case of tenosynovial osteochondromatosis of the extensor tendon of the digit is reported. None of the cases reported in the literature have involved the extensor aspect of the digits. A possible explanation for the paucity of this lesion in relation to the extensor tendons of the digits is the absence of a tendon sheath on the dorsum of the digits.

Chondroma↗
PubMed1985

Metastatic tumor of the hand from malignant cystosarcoma phylloides of the breast. A case report.

In this case report, a malignant cystosarcoma phylloides of the breast metastasized to the pulp of the little finger in a 47-year-old woman. It initially masqueraded as a whitlow. The diagnosis was helped by radionuclide bone scanning, which showed multiple areas of increased focal uptake including the terminal phalanx of the fifth finger, and the diagnosis was established by a frozen section biopsy of the tumor. The patient underwent a palliative fifth ray resection. She died within six weeks of surgery from extensive pulmonary and osseous metastases. Review of literature revealed only one other case of malignant cystosarcoma phylloides of the breast that metastasized to the hand and was initially misdiagnosed as a whitlow.

Breast Neoplasms↗
PubMed1985

Decreased natural killer-type activity of spleen cells against immature thymocytes in autoimmune strains of mice.

Recently we have reported that normal natural killer (NK)-enriched murine spleen cells have the capacity to lyse immature thymocytes of syngeneic or allogeneic origin. The studies presented in this paper show a different pattern of NK-type cytolysis and thymocyte sensitivity in mice which later in life develop autoimmune disease. Such mice appeared to have reduced effector NK capacity and thymocytes from these mice seemed to have reduced sensitivity as targets. This may allow presence and persistence of autoreactive T cell subpopulations which would normally be eliminated.

Animals↗
PubMed1985

Natural killer-type lysis of thymocytes from young mice by normal spleen cells in vitro.

Normal spleen cells from 6- to 10-week-old mice, enriched for natural killer (NK) cells on a discontinuous polyvinylpyrrolidone-silica (Percoll) gradient, lyse thymocytes of young mice (less than or equal to 19 days old) in a short-term 51Cr release assay. The highest NK-type activity was found in band 3 (density less than or equal to 1.077 g/ml) of a four-step gradient. In some experiments band 2 (density less than or equal to 1.070 g/ml) also showed NK activity. Activity was not unequivocably detectable in cells before separation or in bands 1 and 4. These results also show that the thymocyte sensitivity is dependent on the age of the target cell. Sensitivity of very young thymocytes (less than or equal to 7 days old) was higher than that of thymus cells from 8- to 19-day-old donors. Moreover, it seemed that syngeneic target thymocytes were lysed more effectively than allogeneic. Thus, an NK-type cell population may have the ability to lyse immature thymic target cells at an early stage of their differentiation. This could be of importance as a physiological mechanism for controlling the T cell repertoire and its reactivity.

Aging↗
PubMed1984

Subcapsular urinoma: unusual form of "page kidney" in newborn.

The first case of renal hypertension resulting from a urinoma in a kidney secondary to vesicoureteral reflux from posterior urethral valves in a newborn is presented. High-pressure reflux resulted in formation of a subcapsular urinoma. Removal of the nonfunctioning "Page kidney" cured the persistent hypertension.

Humans↗
PubMed1984

Pigmented villonodular synovitis of the wrist invading bone--report of a case.

Pigmented villonodular synovitis of the wrist joint invading adjacent bones rarely occurs. A case in which synovitis invaded the carpal and metacarpal bones at the ulnar aspect of the wrist is described. The invasion of multiple bones by the tumor and its histologic hypercellularity in this case caused concern because of its aggressive behavior. However, review of the literature on pigmented villonodular synovitis arising at the wrist and invading adjacent bones and follow-up of our patient confirmed its benign character.

Adult↗
PubMed1984

Ulnar nerve entrapment neuropathy in the forearm.

A 74-year-old male attorney developed rapidly progressive weakness of the fourth and fifth digits of the right hand with impairment of his grip and ability to perform cursive writing. Lancinating pain occurred spontaneously and was triggered by pressure along the ulnar border of the forearm about 5 cm proximal to the wrist crease. Nerve conduction studies revealed a complete electrical block to stimulation at a point 5 cm proximal to the wrist crease when recording from the abductor digiti minimi. Distal to this point, responses of normal amplitude and latency were recorded. Surgical exploration disclosed two fibrovascular bands coursing from the ulnar artery to the distal belly of the flexor carpi ulnaris, entrapping and grooving the ulnar nerve. Release of these bands resulted in reversal of the electrical block, complete relief of pain, and a full neurologic recovery during the ensuing six months.

Aged↗
PubMed1984

Enrichment of mouse splenic natural killer cells using discontinuous polyvinylpyrrolidone silica (Percoll) gradients.

A simple and rapid method is reported here for enriching murine spleen cells with natural killer (NK) function as assessed by short-term cytolysis assay of 51Cr-labelled YAC-1 lymphoma target cells. The established method used for the enrichment of NK reactive cells, including large granular lymphocytes (LGL) from human and rat peripheral blood lymphocytes, does not substantially enrich for mouse splenic NK cell activity. A reproducible procedure for enriching mouse splenic NK cells has been developed using a four- or five-step discontinuous Percoll gradient in the density range of 1.062 g/ml (top) to 1.092 g/ml (bottom) and osmolarity (310-340 mOsm/kg) nearer to that of mouse blood and tissue. A four- to 25-fold (usually about nine-fold) increase in NK cell activity, consisting of 50-100% of the recovered lytic unit activity, is found in which are the cells forming band 3, approximately 10% of the recovered cell number. This cell population with enriched NK cell activity has a characteristic density less than or equal to 1.077 g/ml, but more than 1.070 g/ml when centrifuged under appropriate conditions. Similar enrichment was obtained with a four-step gradient at an uniform osmolarity of 320 mOsm/kg throughout. Although the lymphocytes in band 3 show relatively little heterogeneity in appearance, only a minor population of the cells contain granules.

Animals↗
PubMed1981

Effect of mitral valvular regurgitation on transthoracic impedance cardiogram.

Mitral valvular regurgitation consistently modified the wave form of the first derivative of the transthoracic impedance cardiogram. The transthoracic impedance cardiogram was recorded in 23 control subjects (group 1), and 23 patients with isolated mitral regurgitation (group 2). Simultaneous transthoracic impedance cardiogram, electrocardiogram, and mitral valve echocardiograms in group 1 showed that the primary diastolic wave ("O") of the transthoracic impedance cardiogram occurred synchronously with the maximal opening of the mitral valve. In group 2, the primary systolic wave (dZ/dt max) was diminished, and the "O" of the transthoracic impedance cardiogram was raised. The area under the systolic wave of the transthoracic impedance cardiogram (S) and the area under the diastolic opening of the transthoracic impedance cardiogram (D) were measured and the ratio D/(D + S) calculated. This ratio, called the mitral regurgitation fraction was (0.50 +/- 0.14) in group 2 which was higher than that found in group 1 control subjects (0.11 +/- 0.08). The mitral regurgitation fraction (15 to 77%) determined by the impedance method was closely correlated with the mitral regurgitation fraction (20 to 74%) obtained during cardiac catheterisation; it also increased during isometric handgrip and decreased during amyl nitrite inhalation. In three mitral regurgitation patients the transthoracic impedance cardiogram returned to normal configuration after surgical implantation of a prosthetic mitral valve. These data suggest that the transthoracic impedance cardiogram is quantitatively altered in patients with mitral regurgitation.

Adolescent↗
PubMed1980

The effect of acute aortic regurgitation on the transthoracic impedance cardiogram.

In nine anesthetized dogs, recordings of the first derivative of the transthoracic impedance cardiogram (ICG) were made during varying grades of acute aortic regurgitation. Acute aortic regurgitation was induced using a specially designed umbrella catheter, passed retrograde across the aortic valve into the left ventricle. The RFA (representing the fraction of the aortic reverse flow to the aortic forward flow) was computed using an electromagnetic flow probe implanted around the ascending aorta. Both the peak of the scalar ICG, dz/dtmax, which occurs at peak systolic ejection, and the nadir of the scalar ICG, X, which marks the closing of the aortic valve, increased with aortic regurgitation. The planimetered areas of the ICG during systole (S), and in early-diastole (X) increased during aortic regurgitation. These areas, S and X, correlated with the electromagnetic normalized aortic stroke volume (r = 0.90) and the regurgitant volume (r = 0.78), respectively. The ICG ratio X/S was correlated directly with the electromagnetic aortic regurgitant fraction (r = 0.86). This study demonstrates that the ICG waveform is consistently modified by experimental aortic regurgitation. Furthermore, these changes can be quantitatively related to the degree of aortic regurgitation.

Animals↗
PubMed1978

Effect of aortic valvular regurgitation upon the impedance cardiogram.

The first derivative thoracic impedance cardiogram, phonocardiogram, and electrocardiogram were recorded in three groups of 22 subjects each. In Group 1 (control), simultaneous impedance cardiogram, phonocardiogram, and aortic valve echocardiograms showed that the X point of the impedance cardiogram occurred synchronously with the aortic second heart sound and with echocardiographic aortic valve closure. In group 2 (clinical diagnosis of aortic regurgitation) the scalar magnitude of the impedance cardiogram O wave and the ratios of the impedance cardiogram wave form X/dz/dtmax and O/dz/dtmax were different from control. In addition, the early diastolic (X) and systolic portions (S) of the impedance cardiogram wave form of group 3 patients were planimetered and expressed as the ratio X/S, called the impedance cardiographic aortic regurgitant fraction (aortic RFI). The aortic RFI was increased by handgrip, a manoeuvre which acutely increases the magnitude of aortic regurgitation. The difference between Fick cardiac output and left ventricular angiographic output was used to calculate aortic valvular regurgitant fraction, which related closely to the impedance cardiogram. These data suggest that it is useful in the noninvasive assessment of aortic regurgitation.

Adolescent↗
PubMed1978

"False inhibition" of demand pacemaker due to leakage of fluid into the pacemaker lead socket.

"False inhibition" of a demand pacemaker usually occurs with a microfracture of the lead system resulting in a galvanic potential at the site of the fracture or with sensing of myopotential with exercise. An increase in the slope of the leading half edge of the pulse contour is generally considered diagnostic of lead fracture. We report the case of a patient in whom "false inhibition" at rest and an increase in the slope of the leading half edge of the pulse contour were caused by leakage of fluid into the pacemaker lead socket.

Aged↗
PubMed1978

Transverse bayonet dislocation of the proximal interphalangeal joint.

Complete dislocation of the proximal interphalangeal joint with complete rupture of both the collateral ligaments and volar plate was seen in 8 patients. We call this, "transverse bayonet dislocation of the proximal interphalangeal joint." When treated early, closed manipulation resulted in stable reduction. After a brief period of immobilization of 3 to 5 days with a dorsal aluminum splint, sustained active range of motion exercises were begun by strapping the injured finger to the adjacent finger obtaining good end results in all cases. An untreated dislocation of 5 weeks duration needed operative reduction. This was achieved with good result by release of all the retaining ligaments around the proximal interphalangeal joint including both the collateral ligaments, the volar plate, the transverse retinacular ligaments, and extensor tenolysis.

Adolescent↗