Biomedical subjects
Publications and source records attributed to M Chacko.
A 27-year-old man suffered a relatively minor trauma. He developed signs of raised intracranial pressure three days after injury. Investigations revealed superior sagittal sinus and torcular thrombosis.
Background: One of the variables most consistently associated with vaginal douching is race, with African-American women douching more regularly. Sparse data exists in the medical literature about the practice of vaginal douching among adolescents. The purpose of this study was to assess the prevalence, knowledge, attitude, and practices of vaginal douching among adolescent females attending a public family planning clinic, and determine whether African-American (AA) females douche to a greater degree than Caucasian females.Methods: In this cross-sectional study, a one-page questionnaire was administered to all adolescent females (</=19 years of age) presenting to a public family planning clinic in a small southern city. Participant charts were abstracted for demographic and clinical information. Chi-square analysis, Pearson's correlation coefficient, and odds ratio were used in data analysis conducted in SPSS for Windows software.Results: Of the 169 participants, the mean age was 17.0 years (+/-1.5 years), 53% were Caucasian, 47% were AA, and 74% were nulliparous. Sixty-nine percent of participants reported vaginal douching, mostly for hygienic reasons (68%). Those reporting vaginal douching were more likely to have a history of one or more sexually transmitted diseases (O.R. 3. 7, 95% C.I. 1.5-9.0, p < 0.01). Age of first douche correlated positively with age of first sexual intercourse (r = 0.34, p < 0. 001). African-Americans did not douche to a greater degree than Caucasians. Among those who douched, AA females were more likely than Caucasians to believe that the reason women douche was after a period (p < 0.01) and after sex (p < 0.05), and to agree that douching clears up a discharge (p < 0.05) and odor (p < 0.01) from the vagina. Caucasians were more likely than AA to believe that some discharge from the vagina is normal (p < 0.05), and most women never need to douche (p < 0.01).Conclusions: Vaginal douching was a common practice among adolescent females attending a public family planning clinic in a small southern city, and racial differences were noted in knowledge of and attitude toward vaginal douching. This suggests development of a culturally-based educational program to convince AA and Caucasian adolescent females to cease vaginal douching.
Clinical assessment of potassium derangements may require evaluation of mineralocorticoid status. Several indirect indices of mineralocorticoid activity based on renal electrolyte excretion have been proposed and include the transtubular potassium gradient, urinary [K]/[Na] ratio, and renal fractional excretion of potassium. We studied the impact of high mineralocorticoid activity versus blocked mineralocorticoid activity on these indices in otherwise normal subjects who ingested a defined diet. Eight normal subjects received either fludrocortisone or spironolactone for 4 days. After a washout period of > or = 2 weeks, each subject then received the opposite regimen. Subjects ingested an identical high-potassium diet during both experimental periods. The renal fractional excretion of potassium and transtubular potassium gradient were calculated using standard formulas. Fludrocortisone caused an increase in body weight and no significant reduction in serum potassium concentration, while spironolactone decreased body weight and increased plasma potassium concentration. After 1 or 2 days of treatment with fludrocortisone, the average values for all urinary indices of mineralocorticoid activity were significantly higher than after 1 or 2 days of treatment with spironolactone. However, the differences between these indices in the fludrocortisone and spironolactone test periods diminished by day 3 and were nonexistent by day 4. In conclusion, the transtubular potassium gradient, [K]/[Na] ratio, and renal fractional excretion of potassium reflect acute changes in mineralocorticoid activity. However, these indices do not discriminate between states of high and low mineralocorticoid activity lasting longer than 2 to 3 days.
A 16-year-old African-American female presented with a 4-week history of intermittent fever, night sweats, and bilateral upper quadrant abdominal pain, bifrontal headache, left eye pain, pruritic rash on arms and chest, 7-kg weight loss, and 2-week history of pain with defecation and urination coincident with the development of perineal ulcers. Her past medical history is unremarkable. Chest x-ray showed bilateral interstitial nodular densities. The laboratory tests that returned positive were herpes simplex culture of the genital ulcer, rapid plasma reagin (1:32), microhemagglutination-Treponema pallidum test, and HIV ELISA and Western blot tests. Open lung biopsy was positive for Histoplasma capsulatum. Syphilis, herpes simplex type II, and HIV infection were all transmitted sexually from a single (and first) sexual encounter a year before admission.
Measurement of specific DNA adduct concentrations in target tissues of organisms may provide a key biologic end-point of exposure to environmental carcinogens. Using a general and highly sensitive assay with 32-P-postlabeling, we found that natural populations of freshwater fish species chub, barbel, bream and carp, as well as a marine fish mugil, revealed the presence of four to nine qualitatively similar adducts irrespective of whether they were caught from unpolluted or polluted waters. No statistically significant differences were observed between the adduct levels of fish from the unpolluted waters and those of fish from the polluted waters. A dominant feature of the fish DNA adducts was a species specificity. The finding that a vast majority of DNA modifications in fish are caused by natural factors rather than man-made chemicals offers a basis for a more realistic view in assessing the genotoxic risks in any aquatic environment.
Tobacco and its combustion products contain several known or potential human carcinogens and studies are now beginning to emerge for detecting DNA and protein adducts in tobacco users. A highly sensitive 32P-adduct assay, capable of measuring a wide spectra of aromatic and/or hydrophobic DNA adducts, was used to evaluate tobacco use-related adducts in human oral mucosal cells. Two volunteer groups of people participated: one, a random group of cigarette smokers (n = 28) with non-smoker controls (n = 13) from our Institute, and the other, a fisherfolk community of tobacco chewers (n = 19) with appropriate non-chewer controls (n = 15) from Bombay. The cells were dislodged from the oral cavity with either a cotton swab or a toothbrush. One to as many as 16 adduct spots in the range of 5-200 amol/micrograms DNA were detected in tobacco users as well as non-users. No adduct spot was detected in the tobacco users' samples that was not present in the controls, suggesting that tobacco use may not be responsible for the formation of these DNA adducts detected in the oral mucosa. The chromatographic behavior of the oral mucosal DNA adducts by selective PEI--cellulose TLC and their extractability in 1-butanol suggest that they have an aromatic and/or hydrophobic moiety and two of the major adducts have been tentatively assigned as aromatic amine derivatives. We have discussed various possibilities of endogenous and/or exogenous factors being involved in the formation of these adducts.
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This study evaluated the effectiveness of telephone reminders on appointment-keeping in young people treated for gonorrhea. Compliance with scheduled follow-up was recorded for a total of 339 patients during three two-week periods, namely, initial baseline phase, intervention phase during which attempts were made to remind the patients by telephone, and repeat baseline phase. There was no overall improvement in compliance with follow-up during intervention (31%), compared to baseline (32%). However, data from the intervention phase revealed a significantly higher rate of appointment-keeping for those patients who were contacted (44%) than for patients who were not reachable (20%). Furthermore, when we reanalyzed the data as a function of telephone ownership for all patients who did not receive a reminder, return rates were significantly higher for patients owning telephones (32%) than for those denying phone ownership (18%). Thus, we conclude that the likelihood for appointment compliance was related more to sociobehavioral factors reflected in telephone ownership than to the telephone reminders.
Metronidazole (MNZ), a widely used therapeutic drug, was administered to male and female Swiss mice intragastrically at a dose of 2 mg MNZ/mouse per day, 5 days a week, every alternate week, throughout their life span to test its carcinogenicity. The treatment induced a significant increase in the overall incidence of tumors in female mice but not in male mice. At the same dose, no teratogenic effect was observed. Perinatal carcinogenicity was studied by following up animals till the end of the F2 generation. Though different groups of animals were considered, a significant increase in tumor incidence was observed only in F1 mice which received MNZ treatment during gestation as compared to the corresponding control mice which received distilled water. The F1 mice which received MNZ during gestation, lactation, and subsequently in adulthood, and the F2 progeny had a tumor incidence comparable to that observed in control mice.
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Preliminary studies on the in vivo and in vitro interactions of 14C-metronidazole with macromolecules showed that the agent or its metabolite(s) can interact with nucleic acids and proteins in vivo. In vitro studies suggest that in absence of DNA synthesis trace amount of metronidazole does bind to DNA/protein and addition of metabolic activation system (from mouse liver) generates more reactive species from metronidazole.
Effect of metronidazole (MNZ) treatment (oral and ip) on activities of cytochrome b5 and P-450 was studied in male, virgin and pregnant female mice. Activities of both the cytochromes increased in virgin mice treated with 2 mg (ip or PO, per mouse) but not in male and pregnant females. 30 mg dose (per mouse) was toxic in pregnant mice but increased the cytochromes activities in males and virgin females. HPLC analysis of liver MNZ levels showed that virgin females had higher MNZ content than male and pregnant females when treated with ip injection of MNZ (250 mg/kg).