Effect of melatonin on gonads, body weight, and luteinizing hormone (LH) dependent coloration of the Indian finch, Lal munia (Estrilda amandava)

Four doses of melatonin were administered intramuscularly over 30 days in separate groups of intact adult male Lal munia, Estrilda amandava, during mid-day (1300 hr) and mid-night (0100 hr) in separate sets during the month of August (late progressive phase), and their effects were studied on the body weight, gonadal and thyroidal activities, and luteinizing hormone (LH)-dependent plumage and beak pigmentation. Melatonin, irrespective of its dose and the time of administration, invariably induced complete inhibition of seasonal gonadal growth and activity, and also the LH-dependent plumage pigmentation. Melatonin had no effect on LH-dependent beak coloration. The inhibitory effect of melatonin on the body weight growth was found to be dependent on the time of administration and the dose of the hormone. Melatonin inhibited the thyroid activity in all the groups. These findings seem to suggest that while melatonin influences gonadal activity, body weight growth, and thyroid activity by acting directly at the hypothalamo-hypophyseal complex, it counteracts the effect of LH at the feather papillae level. Further, synthesis and/or release of FSH seems to be more sensitive to melatonin than that of LH. However, the metabolic action of melatonin might be species specific.     

Subcellular concentrations of estrone, estradiol, androstenedione and 17 beta-hydroxysteroid dehydrogenase (17-beta-OH-SDH) activity in malignant and non-malignant human breast tissues

Total and subcellular (cytosol and nuclear) concentrations of estrone (E1), estradiol (E2), and androstenedione were determined in non-malignant (n = 61) and malignant (n = 65) human breast tissues obtained from post-menopausal women. The 17 beta-hydroxysteroid dehydrogenase (17 beta-OH-SDH) activity was determined in 800g supernatant fraction. Total estrogens, E1 and E2 levels and 17 beta-OH-SDH activity were significantly (p less than 0.005, 0.0005, 0.001, respectively) higher in malignant than in non-malignant breast tissues. We failed to observe significant changes in subcellular steroid concentrations or enzyme activity associated with patients' obesity or tumor estrogen receptor status. When the steroid levels were analyzed in relation to clinical staging of the disease, nuclear contents of estradiol were significantly higher (p less than 0.005) in Stage-IV patients than in those with less advanced disease (Stages I to III). 17 beta-OH-SDH activity was significantly (p less than 0.001) lower in patients with advanced disease than in those with relatively less advanced (Stages I to III) disease and was positively correlated with tissue concentration of androstenedione. Our present data indicate that differential intracellular metabolism of steroid hormones may have some influence on availability of estradiol at nuclear sites. In postmenopausal women, local interconversion of estrogens may provide sufficient estrogenic stimulus to enhance the growth and progression of breast tumors.     

Inhibition of Calcium Oxalate Monohydrate (COM) crystal growth by pyrophosphate,citrate and rat urine

Summary An assay system for the measurement of the rate of Calcium Oxalate Monohydrate (COM) seed crystal growth in a metastable solution of calcium chloride and sodium oxalate containing traces of ¹⁴C-oxalic acid was used to assess the inhibitory activity of pyrophosphate (10^–5 M-10^–4 M), citrate (10^–4 M-10^–3 M) and urines of normal and pyridoxine deficient rats. Both pyrophosphate and citrate were strong inhibitors of COM crystal growth and caused a 50% decrease in crystal growth rate at 1.50×10^–5 M and 2.85×10^–4 M respectively. Normal rat urine strongly inhibited the COM crystal growth, while pyridoxine deficient animals showed a significant (p< 0.01) decrease in mean inhibitory activity as compared to pair-fed controls. A lowered urinary inhibitory potential accompanied with hyperoxaluria and hypercalciuria, which is known to be associated with pyridoxine deficiency, may be a contributory risk of calcium oxalate crystallization and stone formation.     

Sequential radiation changes in cytology of vaginal smears in carcinoma of cervix uteri during radiotherapy

The study deals with acute/immediate radiation changes in 2020 sequential vaginal smears in 101 patients of carcinoma of the cervix uteri, 97 were of squamous cell carcinoma and 4 of adenocarcinoma. The smears were collected after 12-14 days, 15-24 days and 25 days to 6 weeks following radiotherapy. The pretreatment vaginal smears were collected and examined for percentage of cancer cells. Subsequent smears were studied for radiation changes in benign and malignant cells, such as cell size, vacuolation of cytoplasm, multinucleation and nuclear changes, etc. A gradual and linear decline in cancer cells was observed until the end of therapy; 41.6% of patients had less than 10% cancer cells within 12-14 days of therapy, 63.4% of patients between 15 and 24 days and 74.6% after 25 days to 6 weeks following radiation. Eighty three percent of the patients attained zero level at the end of therapy.     

Perigraft seroma: clinical, histologic, and serologic correlates

A 14 year retrospective study of perigraft seroma, defined as an enlarging sterile fluid collection at the site of a prosthetic graft, revealed well-documented cases in 5 of 118 extraanatomical bypasses (4.2 percent), 3 of 248 aortic reconstructive procedures (1.2 percent), and 1 of 395 femoropopliteal bypasses (0.3 percent). These nine cases involved four polytetrafluoroethylene and five Dacron grafts. There were five graft thromboses, one instance of limb loss, two graft infections, two deaths, and 13 separate surgical procedures related to the perigraft seroma. Histologic studies revealed a fibrous pseudomembrane lining the perigraft seroma wall and immature fibroblasts lining the graft. Sera from three patients with perigraft seroma, five patients with well-incorporated prosthetic grafts, and three healthy volunteer subjects were tested for in vitro evidence of fibroblast inhibition against fibroblast tissue cultures derived from the pseudomembrane of a perigraft seroma. Control fetal calf serum, sera from all three healthy subjects, and sera from all five patients with well-incorporated grafts allowed fibroblast proliferation. In contrast, sera from all three patients with perigraft seroma inhibited fibroblast growth. Furthermore, sera collected 1, 2, and 3 months after graft removal from one patient and serum collected 3 months after spontaneous resolution of a perigraft seroma from another patient failed to inhibit fibroblasts. We have concluded that patients with perigraft seroma have a high rate of graft and limb loss and require multiple reoperations. The pathogenesis of perigraft seroma appears to involve a humoral fibroblast inhibitor which prevents maturation and proliferation of perigraft fibroblasts, leading to poor graft incorporation. The decrease of inhibition below detectable levels after graft removal or spontaneous resolution of the perigraft seroma suggests that the graft may induce host production of the inhibitor. Effective therapy of perigraft seroma may include fibroblast modulation, removal of the inciting graft, or both.     

Perforation Rates for Nonsterile Examination Gloves in Routine Dermatologic Procedures

BACKGROUND: Low cost, nonsterile examination gloves are used routinely to perform various dermatologic procedures. OBJECTIVE: To evaluate the perforation rate of nonsterile examination gloves in routine dermatologic procedures. METHODS: Three hundred fifty nonsterile latex examination gloves used to perform shave biopsies were evaluated for perforations using an air inflation/water submersion method. Ninety gloves, which were intentionally perforated with a 30-gauge needle, were used as controls to assess our evaluation method. RESULTS: Eight of the 350 gloves were found to have a perforation, which corresponds to a 2.3% perforation rate. Seven of the eight perforations were found in the web space between the second and third finger sleeves, with one being an obvious manufacturing error. All 90 perforations of the control group were correctly identified. CONCLUSION: There appears to be a very low risk of glove perforation when nonsterile examination gloves are used in routine dermatologic procedures.     

Gene probe for P0 messenger RNA used to index acrylamide toxic neuropathy in rats.

Cumulative exposure to the neurotoxicant acrylamide produces axonal damage in the distal ends of both central (CNS) and peripheral (PNS) nerve fibers and subsequent hind-limb paralysis. The messenger RNA which codes for the PNS myelin glycoprotein P0 (P0-mRNA) was used to monitor this toxic neuropathy in Sprague Dawley rats prior to, concurrent with, and subsequent to, ultrastructurally and immunocytochemically defined nerve damage. Rats were dosed every other day with acrylamide (50 mg/kg, IP) and sampled intermittently throughout a 4 week exposure period. Slot blot and Northern gel analyses of the proximal and distal sciatic nerve were used to determine a quantitated measure of P0-mRNA. Twenty-four hours after the first treatment, in the absence of ultrastructural damage, P0-mRNA increased 55% over control levels in the distal sciatic nerve. After 12 treatments, and concomitant with the appearance of spinal cord and PNS neuropathic damage and hindlimb dysfunction, P0-mRNA decreased 45% below control levels. Levels of P0-mRNA from rats exposed to 12 treatments of acrylamide but allowed to recover for 40 days, returned to 79% of control values to reflect the regeneration and remyelination occurring in the distal sciatic nerve. In spite of these fluctuations in levels of P0-mRNA, immunocytochemical staining of P0 protein in plastic sections of the distal sciatic nerve was present throughout all sample times. These results suggest that changes in neural specific mRNAs are sensitive to neurotoxic damage and can be used to monitor the pathogenesis of nerve degeneration.     

A study on the prevalence of chronic bronchitis in workers exposed to smoke and irritant fumes in a railway workshop.

In the present study 108 full time workers employed in various sections of a railway workshop and exposed to smoke and irritant fumes, and 45 matched control subjects from local administrative staff were investigated to find prevalence of chronic bronchitis. In all 18 (16.7%) workers and 4 (8.9%) control subjects had clinical evidence of chronic bronchitis. Peak expiratory flow rate less than 300 L/min was observed in 54.6% workers and 2.2% control subjects. A significantly higher prevalence of chronic bronchitis was seen in workers. The advancing age, smoking and duration of exposure had significant influence on prevalence of chronic bronchitis.