Biomedical subjects
Publications and source records attributed to M Kumar.
Incidental detection of microfilariae of W. bancrofti in fine-needle aspiration and imprint cytology smears is reported in patients referred for some unrelated complaints.
Highly purified gossypol acetic acid (5 mg/day; oral) alone and in combination with potassium chloride (0.25 mg/day; oral) was tested in adult male langurs for 120 days to evaluate reversibility of its antifertility action and possible hypokalemia. The treatment resulted in severe oligospermia with impairment of sperm motility. Sperm morphological defects were evident. The functional activities of accessory sex glands and libido remained unimpaired. Occurrence of hypokalemia was found more pronounced in the gossypol alone group. Extensive renal potassium loss was evident and conversely the renal excretion of sodium decreased markedly. The activities of serum transaminases increased significantly. Other parameters of blood and of urine did not show any marked alterations. Complete reversal of the above changes was evident following 90 to 105 days of withdrawal of treatment. In conclusion, the oligospermia achieved was reversible and the hypokalemic response of langurs is similar to human and not related to impurity of the drug.
A sensitive, reliable and simplified HPLC assay for simultaneous measurement of 5-hydroxytryptamine (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) in human cerebrospinal fluid (CSF), platelets and plasma is described. Perchloric acid is used for one step precipitation of proteins and extraction of 5-HT and 5-HIAA. Precision of the assay has been increased by calibration of the instrument using serotonin-free plasma spiked with known amount of standards and N-w-methyl-5-hydroxytryptamine as internal standard. Integration of the peaks and calculations are achieved by a preprogrammed data module using ratio method. As little as 20 pg/ml of serotonin in the deproteinated sample can be detected using this procedure. In a group of surgical patients, plasma 5-HT concentration is (Mean +/- S D) 3.4 +/- 2.7 ng/ml and that of platelet 748.3 +/- 448.3 ng/10(9) platelets. In CSF, 5-HT is found to be 3.3 +/- 3.4 ng/ml and 5-HIAA is 15.1 +/- 7.3 ng/ml. A good correlation (r = 0.648, p less than .0001) is observed between 5-HT and 5-HIAA in CSF.
The complications associated with the placement and use of Hickman catheters (n = 120), Broviac catheters (n = 146), and implantable ports (n = 93) in children with cancer were analyzed. Percutaneously placed central venous access devices (CVADs) tended to fail less often (P = .86) and to develop infections less often (P = .056) than surgically placed CVADs. The difference in complications with percutaneous versus surgically placed CVADs requires confirmation in a randomized trial to assure they are not a result of differences in patient characteristics. When all catheter failures (removal due to infection, obstruction, or dislodgement) were considered, ports had a significantly longer failure-free duration of use than externalized Hickman and Broviac catheters (P = .0009). Ports also remained infection-free longer than externalized catheters (P = .0014). The greatest risk of infection occurs in the first 100 days of use, particularly for ports. This study demonstrates that for long-term use (greater than 100 days) ports are superior to externalized catheters in children with cancer.
A case of 14-cm giant-cell tumor of the first metatarsal bone of a 35-year-old male is reported. A ray excision was carried out. The patient has now been free from disease for 3 years.
Fifty symptomatic patients with GERD, 20 each of non ulcer dyspepsia (NUD) & duodenal ulcer (DU) and 10 healthy controls were subjected to various tests employed for diagnosis of GERD. Among these endoscopy and histology had highest sensitivities (92% & 91% respectively) followed by Bernstein's test (overall 88%; early positivity 72%) and oesophagography (70%). The specificities of various tests were: endoscopy (86%), histology (82%) and Bernstein's test (overall 80%; early positive 94%). The false positivity was mainly in DU subjects where majority (greater than 84%) had two or more of these tests offitive. Any two of the three tests (endoscopy, histology & Bernstein's test) in combination had a sensitivity of 80-91% and a specificity of 90-92%. Our observations suggest that these tests, particularly in combination, are useful in establishing the diagnosis of GERD and that subclinical oesophagitis in DU might be responsible for the false positivity of these tests.
The ability of computed tomographic (CT) criteria to predict the potential for resection with renal salvage in unilateral Wilms' tumor was evaluated retrospectively in 10 children given preoperative treatment for initially inoperable disease. Criteria were (a) tumor involving only one pole and occupying less than one-third of the kidney, (b) functioning kidney, (c) no invasion of collecting system or renal vein, and (d) clear margins between tumor, kidney, and surrounding structures. Review of preoperative CT scans correctly predicted nonsalvageability (as assessed by surgicopathologic findings) in seven cases. Sufficient pathologic data were lacking to confirm positive CT predictors in one case. One patient was rated resectable with salvage on surgicopathologic review, but not by CT criteria, and in one case, a prediction could not be made. The potential for renal salvage may be greater in samples with smaller initial tumor size, and addition of other imaging modalities might enhance the accuracy of prediction. Further studies are needed to assess the feasibility of prospective trials evaluating the risks and benefits of partial nephrectomy in unilateral Wilms' tumor.
Explore the source record for details and available documents.
The extrarenal location of Wilms' tumor is extremely rare. These tumors can arise from other neoplasms, generally teratomas, or they can present without any associated teratomatous elements. We encountered only 19 well-documented cases of isolated extrarenal nephroblastoma, and we describe three previously unreported patients with this disease. Two of the three children presented also with horseshoe kidneys, an association that may have clinical and embryologic significance. The presence of tumor cephalad to a horseshoe kidney is easier to explain when we consider that they originate from primitive mesodermal tissue, probably mesonephric rests, and not from metanephric remnants. Also, this association should alert physicians to the possible diagnosis of extrarenal nephroblastoma in patients with a retroperitoneal mass and horseshoe kidneys. These patients should be treated according to the same protocols as those for patients with intrarenal Wilms' tumor.
Fifty-two previously untreated patients with localized Ewing's sarcoma of bone were treated with nonintensive chemotherapy in combination with surgery or radiation therapy (RT). RT was delivered to limited volumes in a dose dependent on the initial response to induction chemotherapy (30 to 35 Gy v 50 to 55 Gy). Fifty of the 52 patients achieved complete or partial responses with induction chemotherapy, with one nonresponding patient rendered free of tumor with surgery. Fifty patients were evaluable for local control of tumor and overall response to protocol therapy. Seventeen relapses have occurred; three metastatic, four local plus metastatic, and ten local. Two factors predicted worse disease-free survival: high WBC count (P = .03) and size of primary tumor (P = .05). Of the 14 local recurrences, 12 occurred in 28 patients who presented with primary tumors greater than 8 cm in size while only two of 22 patients with lesions less than 8 cm had local recurrence. The Kaplan-Meier estimate of disease-free survival at 3 years is 82% for those with small lesions and 64% for those with larger lesions. Site of primary was of no prognostic value (P = .27). The 5-year survival estimate for all patients is 80% (median time on study, 3.3 years).
We prospectively studied the continuous function and complication rates of 286 central venous catheters consecutively placed in 264 children and young adults at a single institution over a 19-month period (median follow-up, 376 days). Externalized catheters (91 Hickman [H], 113 Broviac [B]) and implantable ports (n = 82) were compared for complications, including infection and thrombosis. The most frequent major complication of all catheters was infection, although the rates of infection varied with the duration of catheter use and were generally lower than reported by others. Overall, when catheter failures (removal) for infection, obstruction, or dislodgement were considered, ports had a significantly longer failure-free duration of use (P = .0024) than did externalized catheters. Likewise, ports had a significantly longer infection-free (P less than .01) duration of use than H and B catheters. However, differences in patient age and clinical characteristics among the three catheter groups may have affected the outcome. In analysis of pairs matched for diagnosis, therapy, and age, ports had lower infection rates than did B catheters after 100 days (P = .053). This difference became significant at 400 days of catheter use (P = .029). Although there was a trend toward lower rates of infections for ports v H catheters, this difference was not significant. In view of our results in matched pairs, selection of catheter type based on clinical characteristics and patient preferences remains a reasonable therapeutic approach despite the apparent advantages of ports. The superiority of ports for long-term use (greater than 100 days) needs to be confirmed in a large randomized clinical trial.
Explore the source record for details and available documents.
Twenty-seven cases of Post Kala-Azar Dermal Leishmaniasis (P. K. D. L.) were detected in an endemic focus of Kala-azar in Sujabad village in Varanasi Distt. Male-Female ratio of cases was 4.4:1. Majority (66.6 per cent) of cases had macular lesions. Histopathology of one case showed Leishmania donovani (L. D.) bodies. Densities of sand fly were more in pockets where P. K. D. L. cases were detected. All the 13 cases, which were treated with sodium antimony gluconate, responded well to therapy.
To determine the role of autoantibodies in the development of the AIDS dementia complex, brain-reactive antibodies (BRAs) were assayed in 30 sera samples obtained from AIDS patients. Eighteen samples were obtained from AIDS patients with neuropsychological complications, and 12 samples were obtained from patients without any neuropsychological involvement. BRAs were analyzed using strips of nitrocellulose electroblots as a source of antigen, and were prepared from a sample of normal human parahippocampal tissue subjected to SDS-PAGE. Fourteen of 18 patients with neuropsychological complications and 4 of 12 patients without such complications were positive for BRAs to a protein with Mr of 45,000-50,000.
The efficacy and safety of six regimens of treatment for kala-azar (visceral leishmaniasis) with sodium stibogluconate were evaluated in a prospective randomised study to ascertain the optimal treatment for Indian patients. Altogether 371 patients with kala-azar were randomised to receive sodium stibogluconate intramuscularly at a dose of 10 mg/kg body weight/day for 20 or 40 days (groups A and A1, respectively), 15 mg/kg body weight/day for 20 or 40 days (groups B and B1, respectively), or 20 mg/kg body weight/day for 20 or 40 days (groups C and C1, respectively). Patients were examined blind before and at the end of treatment and every month for six months. The number of patients who were apparently cured--that is, those whose temperature had returned to normal at the end of their regimen of treatment--was 45 (78%) in group A, 53 (87%) in group A1, 50 (81%) in group B, 60 (95%) in group B1, 58 (92%) in group C, and 62 (97%) in group C1. At six months 62 patients (97%) in group C1, 51 (81%) in group C, 54 (86%) in group B1, 42 (68%) in group B, 45 (74%) in group A1, and 33 (57%) in group A had not relapsed and were cured as confirmed by a bone marrow aspirate free of parasites. The differences between groups C1 and C, B1 and B, and A1 and A were significant. Logistic regression of the proportion cured with the dose and length of treatment showed that both factors were significant in improving the rate of cure; the highest dose for the longer time (group C1) had the best rate of cure. One patient in group C1, 12 in group C, nine in group B1, 18 in group B, 15 in group A1, and 23 in group A were cured with extended courses of 20 mg sodium stibogluconate. One patient in each of groups C1, B, A1, and A became unresponsive to antimony and were cured with pentamidine. One patient in each of groups C1, B, and A became unresponsive to both antimony and pentamidine. The patients tolerated the longer duration of treatment safely, and side effects were minor. Sodium stibogluconate should be given intramuscularly in the dosage of 20 mg/kg for at least 40 days, when patients should be assessed for further treatment if necessary. Such a regimen should achieve the highest rate of cure with low toxicity and low rates of relapse and unresponsiveness.
The hydrated volumes, Vh, of collagens extracted from various fish species were calculated by using the Simha-Einstein equation, and it was found that the hydration of warm-water fish collagen is greater than that of cold-water fish collagen (halibut). Although the intrinsic viscosities of warm-water fish (bigeye-tuna, carp and catfish) collagens are almost the same, the hydrated volume of bigeye-tuna collagen is approx. 1.5 and 3 times those of carp and catfish collagens respectively. The extent of hydration at 20 degrees C is in the following order: bigeye tuna greater than carp greater than catfish greater than halibut. The various thermodynamic activation parameters (delta G*, delta H* and delta S*) were calculated and it was found that they are useful for determining the exact denaturation temperature. It was calculated that the denaturation temperatures of halibut, bigeye-tuna, carp and catfish collagens are 17, 31, 32 and 26-30 degrees C respectively. The variations of hydration, intrinsic viscosity, denaturation temperature and the thermodynamic parameters with the variation of concentration of catfish collagen were also thoroughly examined. The change of thermodynamic parameters from coiled-coil to random-coil conformation upon denaturation of collagen were calculated from the amount of proline and hydroxyproline residues and compared with viscometric results.
Serum LDH-isoenzyme studies revealed that in carcinoma cervix, the principal activity was confined to LDH-2 and LDH-3 with a significant rise in LDH-2 fraction when compared with the control values (P less than 0.001). Radiotherapy caused significant lowering of LDH-2 and LDH-3 (P less than 0.001 in each case). There was no relation of LDH-isoenzyme distribution in different clinical stages and morphological distribution within the tumor. Further, LDH-2 and LDH-3 were found to be lowered significantly in good and moderate clinical radiation response (CRR) groups (P less than 0.001 in each case) but in poor CRR group no significant change in LDH-2 and LDH-3 was observed following radiotherapy. LDH-isoenzyme determination in carcinoma cervix is very helpful in assessing the treatment response following radiotherapy and thus may be an important prognostic parameter.
Complexes of Mn(III), Fe(III), Fe(II), Co(III), Ni(II), Cu(II), Zn(II), and Pt(II) with S-methyl-N-(l-isoquinolyl) methylendithiocarbazate (N-N-SH) were isolated and characterized by elemental analysis, conductance measurement, magnetic susceptibilities, and spectroscopic studies. On the basis of these studies, a highly distorted, high-spin, chloro-bridged, polymeric octahedral structure for [Mn(N-N-S)Cl2]; a distorted, low-spin, monomeric octahedral structure for [Fe(N-N-S)2]; a distorted, high-spin, octahedral structure for [Ni(N-N-S)2]; and a square-planar structure for [M(N-N-S)X] (M = Ni, Cu, Pt or Zn and X = Cl- or -OAc) are suggested. With Fe(III), the complex [Fe(N-N-S)2][FeCl4] was isolated while the Co(II) was oxidized to yield the Co(III) ion as [Co(N-N-S)2]2[CoCl4]. All these complexes were screened for their antitumor activity against P 388 lymphocytic leukemia test system in mice. Except for Mn(III), Fe(III), and Co(III) complexes, all were found to possess significant activity; the Cu(II) and Zn(II) complexes showed a T/C% value of 160 and 195, respectively, at their optimum dosages.