Reasons for increased incidence of tuberculosis. Large immigrant population may have confounded study.
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Biomedical subjects
Publications and source records attributed to D Kumar.
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A model that makes use of the cooperative organization of inorganic and organic molecular species into three dimensionally structured arrays is generalized for the synthesis of nanocomposite materials. In this model, the properties and structure of a system are determined by dynamic interplay among ion-pair inorganic and organic species, so that different phases can be readily obtained through small variations of controllable synthesis parameters, including mixture composition and temperature. Nucleation, growth, and phase transitions may be directed by the charge density, coordination, and steric requirements of the inorganic and organic species at the interface and not necessarily by a preformed structure. A specific example is presented in which organic molecules in the presence of multiply charged silicate oligomers self-assemble into silicatropic liquid crystals. The organization of these silicate-surfactant mesophases is investigated with and without interfacial silicate condensation to separate the effects of self-assembly from the kinetics of silicate polymerization.
OBJECTIVE: To examine the longitudinal relationship between surgeon volume and in-hospital mortality for coronary artery bypass graft (CABG) surgery in New York State and to explain changes in mortality that occurred over time. DESIGN: Observation of clinically risk-adjusted operative mortality over time. SETTING: All 30 New York State hospitals in which CABG surgery was performed for 1989 through 1992. PATIENTS: All 57,187 patients undergoing isolated CABG surgery in New York State in 1989 through 1992 in the 30 hospitals. MAIN OUTCOME MEASURES: Actual, expected, and risk-adjusted mortality. RESULTS: Risk-adjusted in-hospital mortality decreased for all categories of surgeons. Low-volume surgeons (< or = 50 operations per year) experienced a 60% reduction in risk-adjusted mortality in the 4-year period, whereas the highest-volume surgeons (> 150 operations per year) experienced a 34% reduction. The percentage of patients undergoing CABG surgery by low-volume surgeons decreased from 7.6% in 1989 to 5.7% in 1992, a 25% decrease. CONCLUSIONS: The overall decline in risk-adjusted mortality could not be explained by shifts in patients away from low-volume surgeons to high-volume surgeons. The proportionately larger decrease in risk-adjusted mortality for low-volume surgeons could not be explained by changes in patient case mix or by improvements in the performance of surgeons with persistently low volumes. Part of the decrease was a result of the exodus of low-volume surgeons with high risk-adjusted mortality (in all years studied), the markedly better performance of surgeons who were new to the system (especially in 1991 and 1992), and the performance of surgeons who were not consistently low-volume surgeons (especially in 1992).
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Neosphincter formation with gracilis muscle is used for faecal incontinence refractory to conservative measures and after failed sphincter repair. In this study both gracilis muscles were used to create a neosphincter to determine whether this provides superior physiological and clinical results. Ten patients of median age 39 (range 18-73) years were treated. The mean resting and squeeze pressures before operation were 16 (range 0-40) and 44 (range 0-68) cmH2O respectively. The operation was covered by a defunctioning loop left iliac fossa colostomy. Nine of the ten patients have had the stoma closed and are fully continent after a mean follow-up of 24 (range 6-40) months. One patient who had an ileoanal pouch and bilateral graciloplasty has urgency of defaecation. None of the patients has to wear a pad or is taking constipating agents. All nine patients have satisfactory evacuation on isotope defaecography and are continent to artificial stool. After operation the mean resting and squeeze pressures were 78 (range 70-112) and 121 (range 90-188) cmH2O respectively. Bilateral graciloplasty provides satisfactory results for grade 4 faecal incontinence refractory to other operative and non-operative measures, and may be an alternative to stimulated dynamic graciloplasty.
Forty nine patients with mycologically confirmed Tinea cruris were investigated for the association of hypersensitivity to trichophytin and the isolation of dermatophytes from clinically normal sites with chronicity and recurrence of infection. At the end of six months following specific therapy, 24 patients returned for follow up and they were similarly studied. Dermatophytes were isolated from clinically asymptomatic sites in 46% patients before treatment and in 21% of the patients on follow up. Immediate weal reaction and increased concentration of IgE antibodies were seen in 73% and 80% of the patients respectively. However, the delayed hypersensitivity reaction was more associated with patients having lesions for more than 6 months (48%) in comparison with patients with a short history (17%). On follow up after 6 months, the different hypersensitivity reactions and IgE antibody concentration maintained more or less the same association. Therefore in persistent or recurrent Tinea cruris infection, besides potential carriage in clinically normal sites, hypersensitivity to antigens of dermatophytes possibly plays an important role in pathogenicity.
PURPOSE: This study was designed to examine the role of adjuvant internal anal sphincter plication in women with neuropathic fecal incontinence undergoing pelvic floor repair. METHODS: We completed a randomized trial with symptomatic and physiologic assessment before and after surgery. RESULTS: There was no symptomatic advantage of adding internal sphincter plication; the mean improvement of functional score was 3.61 +/- 1.82 (standard deviation; P < 0.01) following pelvic floor repair alone compared with 2.80 +/- 1.66 (standard deviation; P < 0.01) when adjuvant internal and sphincter plication was added. The addition of internal sphincter plication was associated with a significant fall in maximum anal resting and squeezing pressures (P < 0.01). CONCLUSIONS: Addition of internal sphincter plication is not advised in women with neuropathic fecal incontinence treated by pelvic floor repair.
The no-effect limit dose (NELD) of three commonly used pesticides with respect to their cytogenetic toxicity was determined in a number of test systems using a sufficient number of lower doses to characterize the dose-effect relationship. For lindane, malathion and metacid, this dose was 3.2, 7.0 and 3.0 mg/litre, respectively, for mitosis inhibition and 9.0, 55 and 60 mg/litre, respectively, for chromosome clastogeny in onion root-tip cells. For chromosome clastogeny in mice bone marrow cells, the NELDs of the three pesticides were 1.6, 1.5 and 2.0 mg/kg body weight/day, respectively. These values for dominant lethals and X-chromosome-linked recessive lethals in Drosophila were 20 and 5 micrograms lindane/litre, 2 and 3.5 micrograms malathion/litre and 4 and 5.5 micrograms metacid/litre, respectively. Thus, the NELDs are not only pesticide specific but also organism specific, tissue specific and even damage specific. Furthermore, the NELD values determined are so small that the real human exposure to pesticides cannot be reduced below these levels without compromising the effectiveness of pesticides in use.
Pseudoepitheliomatous hyperplasia (PEH) arises in areas of chronic inflammation and can be mistaken for squamous cell carcinoma, leading to unnecessary removal of more tissue. We present a study of 21 patients having delayed reconstruction of defects left by Mohs micrographic surgery (MMS) to remove facial skin cancers. Reconstruction was done at an average of 6 days after MMS. Four of these 21 patients (19%) had PEH in the wound margins. Presence of PEH did not correlate with age, sex delay in reconstruction, frequency of wound care, size or location of the defect, type of tumor, or smoking status. During an average 24-month follow-up, none of these four patients had tumor recurrence, suggesting that the benign diagnosis of PEH was correct. We detail the histologic features of PEH, and describe techniques for minimizing confusion with squamous cell carcinoma.
This study describes a graphic presentation of the results of a simplified segmental colonic transit model. This study requires three sets of images on three consecutive days after intake of indium-111 resin capsule at each time point. The per cent of ingested activity is calculated in each region of the colon and in the faeces. The program uses standard PC compatible graphic package, CorelDRAW (Corel Corporation). The report for the patients' notes consists of three schematic diagrams of colon with regions identified and a pot representing the faecal activity. The per cent of administered activity in each region and pot is both printed and represented by shades of grey (white representing 0% and black 100% activity), for each region and the pot. The distribution of activity is clearly seen at each time point and the report is presented on single A4 size sheet of paper. Using a simplified colonic study protocol it is possible to produce clinician friendly reports on a single sheet of paper.
This study investigated the hypothesis that some features of functional gastrointestinal disorders may be associated with abnormalities of ileocaecal transit by measuring ileocaecal transit using a scintigraphic technique in 43 patients with chronic constipation, 20 patients with irritable bowel syndrome (IBS), and 18 control subjects. Subjects ingested enteric coated capsules, which delivered 111-indium radionuclide to the distal ileum. Gammacamera images were acquired at hourly intervals until caecal filling was complete. Ileocaecal transit was defined as the time between peak scintigraphic activity in the terminal ileum and peak activity in the caecum. The mean (SD) ileocaecal transit of 103 (50) minutes in patients with IBS was significantly faster than that in control subjects (mean (SD) ileocaecal transit 174 (78) minutes, p < 0.002). There were no significant differences in ileocaecal transit between patients with chronic idiopathic constipation and the control subjects, or between patients with constipation predominant and diarrhoea predominant IBS. This study developed a practical scintigraphic method of measuring ileocaecal transit. The rapid ileocaecal transit in both the constipation and diarrhoea predominant forms of IBS suggests that bloating may not after all result from delayed ileal emptying.
This report describes the occurrence of splenic lymphoma with villous lymphocytes (SLVL) in a 56 year old white female with a family history of chronic lymphocytic leukaemia. Other unusual features included a marked lymphocytosis with counts up to 224 x 10(9)/l and marked clumping of lymphocytes in EDTA anticoagulated blood. The neoplastic cells were CD19+, CD20+, CD22+, CD22+, IgM+, lambda+, kappa-, CD5-, and CD10-. The spleen had nodular infiltrates of B lymphocytes in the region of the white pulp with minimal red pulp involvement. Electron microscopy of peripheral blood lymphocytes revealed cells with polar cytoplasmic processes. This report underlines the need for detailed analysis, including morphology and immunophenotyping, for each patient with a small B cell lymphoproliferative disorder.
STUDY OBJECTIVE: To estimate the prevalence of active pulmonary tuberculosis in a homeless population in London and to assess whether those with suspected disease could be integrated into the existing health care system for further follow up and treatment. DESIGN: Voluntary screening programme based on a questionnaire survey and chest x ray. SETTING AND CASES: Screening programmes were set up over the Christmas period in 1992 and 1993 at a shelter for the homeless in London. An offer of screening was made to all individuals who visited the centre and an interviewer administered questionnaire was completed on those who volunteered for the screening. Chest x rays were carried out, developed, and read on site. Individuals with chest x rays features suggestive of tuberculosis or other medical problems were referred to a hospital of their choice. RESULTS AND OUTCOME: In 1992 nearly 1600 people visited the centre, of whom 372 volunteered for the screening and 342 were x rayed. Nineteen of the 342 (5.6%) had radiological features suggestive of active tuberculosis. In 1993 around 2000 homeless people visited the centre, of whom 270 volunteered for the screening and 253 were x rayed. Eleven (4.3%) had features consistent with active tuberculosis on the basis of the chest x rays and clinical examination by a chest physician. Overall, of 595 people x rayed in the two surveys, 30 (5%) had changes suggestive of active tuberculosis. Further investigations confirmed nine (1.5%) with active pulmonary disease and eight with no active tuberculosis. In 13, the diagnosis was not determined as four declined further investigation and nine did not attend their hospital appointment. CONCLUSION: Tuberculosis among the homeless remains a cause for concern. Follow up and treatment present unique difficulties. Services for the homeless need to include mechanisms for timely diagnosis and monitored treatment. Control programmes designed for the needs of the homeless are required.
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Many antibiotics have been shown to have adverse effects on spermatogenesis. Deoxyribonucleic acid (DNA) flow cytometry of testicular aspirate has been shown to be an effective method of quantitatively evaluating testicular function. To assess this problem, DNA flow cytometry of testicular aspirate was performed on 8 groups of rats, each of which received antibiotics via daily gavage for 10 days. Aspirations were performed on days 0, 11 and 56. Data thus obtained were analyzed using a two-way ANOVA with repeated measures. Antibiotics studies included ciprofloxacin 15 mg./kg./day, sulfamethoxazole (SMX) 20 mg./kg./day (with trimethoprim (TMP) 4 mg./kg./day), nitrofurantoin 7 mg./kg./day, ofloxacin 10 mg./kg./day, lomefloxacin 6 mg./kg./day, doxycycline 3 mg./kg./day and norfloxacin 10 mg./kg./day. One group received the same SMX/TMP dose, together with folate 0.014 mg./kg./day. A statistically significant change in aspirate content on day 11 as compared with baseline existed in groups receiving TMP/SMX (p = 0.00025), nitrofurantoin (p = 0.0000043), ofloxacin (p = 0.000075) and doxycycline (p = 4.89 X 10(-9). Control rats and the group receiving TMP/SMX with folate showed no significant change. On day 56 the abnormality persisted in groups TMP/SMX (p = 0.042), nitrofurantoin (p = 0.001), ofloxacin (p = 0.036) and doxycycline (p = 0.003). Controls and groups receiving ciprofloxacin, norfloxacin and lomefloxacin continued to show no statistically significant difference from baseline on day 56. These data suggest that SMX/TMP, nitrofurantoin, ofloxacin and doxycycline significantly alter spermatogenesis. Ciprofloxacin, norfloxacin and lomefloxacin had no apparent effect on spermatogenesis as measured by DNA flow cytometry.
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A retrospective analysis of 29 cases of pituitary tumours with suprasellar extension that had undergone surgery by transsphenoidal or transcranial route, was done. The correlation between age, duration of symptoms, pre- and post-operative visual acuity, visual field and suprasellar height of the tumour were analyzed. The age and duration of visual loss were found to have a bearing on the final postoperative visual outcome.