Effect of inhaled methanol on pituitary and testicular hormones in chamber acclimated and non-acclimated rats.

Two experiments were conducted in which the acute effects of inhaled methanol on serum hormones associated with reproductive function in the male rat were evaluated. In the first experiment, rats exposed to methanol (0, 200, 5000 and 10,000 ppm) for 6 h were killed at the end of the exposure period (6 h) or the following morning (24 h). Also, because the process of exposure itself could modify neuroendocrine function, the effect of the handling associated with placing the rat in the exposure chamber was evaluated further by dividing the exposed animals into acclimated (2 weeks of prior handling) and non-acclimated groups. At 6 h, an effect of prior handling was noted in the sham-exposed rats, with serum luteinizing hormone (LH) of the non-acclimated group being greater than that of the acclimated group. Serum LH concentrations were altered by methanol exposure, but the direction of change and the exposure level at which an effect was noted differed between the acclimated and non-acclimated rats. Methanol (5000 ppm) reduced serum LH in the non-acclimated animals, while 10,000 ppm increased LH in the acclimated rats. Follicle stimulating hormone (FSH) and testosterone were unchanged by methanol in rats killed at 6 h. Thus, this experiment did not confirm earlier reports that exposure to 200 ppm for 6 h reduced serum testosterone. At 24 h, an effect of prior handling was still present in the hormonal measures, with serum and interstitial fluid testosterone concentrations being greater in the non-acclimated rats. Also, there was a dose x handling interaction with methanol exposure inducing an increase in serum testosterone in the non-acclimated rats (up to 5000 ppm) and a decrease in the acclimated rats (up to 10,000 ppm). In the second experiment, groups of acclimated and non-acclimated rats were exposed to 0 or 5000 ppm methanol for 1, 2 and 6 h and killed immediately after removal from the chamber. Serum LH, testosterone and FSH values were not different in sham- vs methanol-exposed rats at any time point. As in experiment 1, an effect of prior handling was noted. In general, the concentrations of these hormones and serum prolactin in the non-acclimated rats were greater than those observed for acclimated rats. Methanol exposure resulted in increased prolactin concentrations under both handling conditions.(ABSTRACT TRUNCATED AT 400 WORDS)     

Split skin grafting using topical local anaesthesia (EMLA): a comparison with infiltrated anaesthesia

The analgesic efficacy of EMLA cream was compared with that produced by infiltration of lignocaine solution when used to provide anaesthesia for cutting of skin grafts. The study was performed as an open parallel group comparison in 80 patients. Pain felt during administration of the anaesthetic and during cutting of the graft was assessed using visual analogue and verbal rating scales. During graft cutting, the anaesthesia produced by EMLA was at least as effective as infiltration. On administration, infiltration produced varying amounts of pain in all patients, but in contrast EMLA produced no discomfort. In view of this lack of discomfort and the consequent greater freedom afforded regarding the area of donor site anaesthetised, EMLA can be considered the treatment of choice when skin grafts are harvested under local anaesthetic.     

Common bile duct calculi: updated experience with dissolution with methyl tertiary butyl ether

The authors describe their experience with methyl tertiary butyl ether (MTBE) in a larger series of patients than previously reported in order to acquaint physicians with both its effectiveness for dissolution of common bile duct calculi and the limitations of its use. Ten patients with 13 biliary calculi underwent percutaneous stone dissolution treatment with the experimental cholesterol solvent, MTBE. Three stones completely dissolved within 30 minutes, seven were reduced in size, and three were visibly unaffected. All stones not completely dissolved were easily extracted by means of a stone basket except for one in a patient taken to surgery. Although MTBE perfusion is an effective technique for management of biliary calculi, practitioners should be aware that its use is quite time consuming and its odor difficult to control.     

Expression of cadherins and CD44 isoforms in ovarian endometrial cysts

We evaluated the immunohistochemical expression of cadherins and CD44 variants in 20 endometriomas, 20 cystadenomas, 20 borderline ovarian tumours as well as 20 ovarian carcinomas, and the serological and cystic fluid concentrations of soluble E-cadherin and soluble CD44 standard (sCD44sdt) in 20 endometriomas, 20 cystadenomas, six borderline and 11 carcinomas of the ovary. In endometriomas, immunostaining of E- and N-cadherin was negative (20 and 30% respectively). CD44 H, v3 and v6 immunostaining were detected in 63, 10 and 40% respectively. A difference in immunostaining for E-cadherin was found between endometriomas and cystadenomas (P < 0.001) and for N- cadherin between endometriomas and carcinomas (P < 0.001). A difference in CD44H immunostaining was observed between endometriomas and cystadenomas (P < 0.035) but not with borderline ovarian tumours and carcinomas. No difference in serum concentrations of soluble E- cadherins and CD44 standard was found between the four groups of tumours. Cystic fluid concentrations of E-cadherin were lower in endometriomas than in borderline tumours and ovarian carcinomas (P < 0.001). High concentrations of soluble CD44 standard cystic fluid were found in endometriomas than in other ovarian cysts. Endometriomas and borderline tumours share alterations of cadherins and CD44 isoforms which may help in the understanding of the aggressive and invasive potentials of endometriotic cells.      

Genital asymmetry in men

This study examined genital asymmetry in a large sample of men. The probands were 6544 non-delinquent men who were interviewed by the Kinsey Institute for Research in Sex, Gender and Reproduction from 1938 to 1963. The measures were four indicators of penile and scrotal asymmetry, along with self-reported handedness, from Kinsey's interview protocol. Most men reported some degree of lateral asymmetry in their flaccid penis and in their testicles; less asymmetry was reported for their erect penis. The asymmetry typically occurred in the left direction, and this pattern occurred in both right- and nonright- handers. However, this 'leftward' pattern was significantly less pronounced in nonright-handers. The results are discussed in relation to previous findings of genital asymmetry in men, the possible relationship of genital asymmetry to functional cerebral asymmetry, and recent data suggesting genital asymmetry may predict patterns of cognitive performance and genital/sexual organ cancers.      

The Radiologic Features of Non-Neoplastic Tumors of Soft Tissue

Neoplasms of the soft tissues cause localized swelling and a variable degree of tissue response on the part of the host; these features they share with many non-neoplastic disorders. A spectrum of lesions that may simulate soft tissue neoplasms are described, with their radiologic appearances. The cellular nature of the matrix of a lesion cannot be identified absolutely as neoplastic by current imaging methods. Although sonography and magnetic resonance imaging can each produce valuable diagnostic information hitherto not provided by imaging the soft tissues, they do not per se show evidence of neoplasia. The differentiation of the two types of tumor, neoplastic and non-neoplastic, can only be achieved by a combination of clinical, radiologic and histologic information. Ultimately, biopsy with histologic examination may be required for the definitive diagnosis.     

Neuroendocrine and reproductive effects of contemporary-use pesticides

Work in our laboratory has focused on the hypothesis that certain environmental contaminants will interfere with reproductive function because they disrupt the neuroendocrine regulation of gonadal function. In this article, we review the evidence that certain classes of contemporary-use pesticides alter gonadotropin secretion through a disruption of hypothalamic mechanisms. Specifically, we discuss the effect of formamidine and dithiocarbamate pesticides on the noradrenergic control of pituitary hormone secretion, ovarian function, and pregnancy in the rat. This is followed by a review of studies evaluating the effect of a chlorotriazine herbicide, atrazine, on the hormonal control of ovulation and lactation. We also discuss the physiological consequences of these endocrine alterations in the female, how toxicant-induced endocrine alterations may differ in physiological outcome in the male and female, and the fact that the reproductive risk assessment of some pesticides that act on the central nervous system (CNS) may be influenced by the development of tolerance.