Chronic neurobehavioural effects of toluene

Neurobehavioural tests were undertaken by 30 female workers exposed to toluene and matched controls with low occupational exposure to toluene. The environmental air levels (TWA) of toluene was 88 ppm for the exposed workers and 13 ppm for the controls. The toluene in blood concentrations for the exposed workers was 1.25 mg/l and for the controls 0.16 mg/l. Statistically significant differences between workers exposed to toluene and controls in neurobehavioural tests measuring manual dexterity (grooved peg board), visual scanning (trail making, visual reproduction, Benton visual retention, and digit symbol), and verbal memory (digit span) were observed. Further, the performance at each of these tests was related to time weighted average exposure concentrations of air toluene. The workers exposed to toluene had no clinical symptoms or signs. The question arises as to whether these impairments in neurobehavioural tests are reversible or whether they could be a forerunner of more severe damage.     

Use of xanthan gum in dietary management of diabetes mellitus

Xanthan gum (12 g/day) was fed in muffins during either the first or second half of a 12-wk period of muffin feeding, to free-living subjects. Nine subjects were diabetic, having moderately elevated serum glucose but managing without insulin or hypoglycemic drugs, and four were nondiabetic controls. Before the study and at the end of the xanthan and xanthan-free periods, bloods were taken before and 2 h after an oral glucose load. The feeding of xanthan gum lowered fasting and postload serum glucose and reduced fasting levels of total plasma cholesterol in diabetic subjects. Xanthan gum also tended to lower fasting and postload levels of gastrin and gastric inhibitory polypeptide (GIP) and fasting levels of total and VLDL triglyceride and cholesterol in VLDL and LDL fractions. Subjects reported a sense of fullness after consuming xanthan muffins but no severe digestive symptoms.     

Use of pulse oximetry for monitoring tracheostomy tube obstruction

Experimental studies were performed on dogs for monitoring postoperative tracheostomy tube obstruction using a pulse oximeter. While a 25% obstruction of the cross-sectional area of the tube did not alter the oxygen saturation, obstruction of 40% and above resulted in a drop in the oxygen saturation level which corresponded to the degree of obstruction. The greater the degree of obstruction, the sooner was the fall of oxygen saturation. Therefore a pulse oximeter could be effectively put to use to monitor tracheostomy tube obstruction.     

Induction of testicular DNA synthesis in vitro by hCG and hMG treatments in men with hypogonadotropic hypogonadism

To study the effectiveness of hCG and hMG administration on spermatogenesis of patients with hypogonadotropic hypogonadism (HH), the DNA synthesis of spermatogonia was investigated by the method of 3H-thymidine uptake by cultured tissue fragments of human testis with or without treatment with hCG and/or hMG. Although in two groups treated with different concentrations of hCG the value of 3H-thymidine incorporation into testicular tissue showed no significant difference compared with the untreated control group, treatment with both hCG and hMG induced significant changes in the value of 3H-thymidine incorporation compared with the untreated control group. Combined hCG and hMG therapy was effective for induction of spermatogenesis in patients with HH.     

Improvement of semen characteristics after surgical repair of bilateral testicular varicocele as compared to unilateral varicocele patients

The operative treatment for surgical repair of bilateral testicular varicoceles was evaluated in terms of the improvement achieved in the sperm density and percentage progressive motile sperm. These parameters were compared for 27 cases of bilateral varicocele diagnosed by palpation and subjected to bilateral high ligation of the internal spermatic vein and for 40 cases of left unilateral testicular varicocele. There were no significant differences in preoperative values (such as sperm density; progressive motile sperm; serum levels of luteinizing hormone, follicle-stimulating hormone, and testosterone; and Johnson's score count) between the bilateral and unilateral testicular varicocele groups. The improvement in postoperative sperm density in the cases with bilateral testicular varicocele was apparently less satisfactory than in the cases with testicular varicocele only on the left side.     

Changes in the hormone receptors of human breast carcinoma xenografts in nude mice by treatment with cytotoxic agents

We examined the effect of chemotherapeutic agents on the estrogen receptors (ER) of breast carcinomas in vivo using human breast carcinoma strains (Br-10, T-61) serially transplanted into nude mice. When the tumor size reached approximately 1 X 1 X 1 cm, mitomycin C (MMC) at doses of 1, 2 and 4.5 mg/kg and cyclophosphamide (CPA) at a dose of 120 mg/kg, were administered once intraperitoneally, and the ERs of the tumors were measured sequentially by the dextran-coated charcoal method. Four days after the MMC administration at above doses, the binding sites of ER in Br-10 were not reduced and binding affinity was not affected. When the changes in ER content with time after the treatment with 4.5 mg/kg MMC and 120 mg/kg CPA were investigated, the ER content was found to be stable until 4 days after the treatment with both drugs, although the growth of T-61 had been significantly inhibited by the drugs. From these findings, it seems reasonable to initiate chemotherapy before endocrine therapy, since the chemotherapeutic agents did not reduce the ER content of the breast cancer strains.     

A multipurpose dye laser photocoagulation system

We modified a single argon/dye laser photocoagulator by adding two optical fibers so that it could be used with a slit-lamp microscope, an operating microscope, and with an endophotocoagulation probe. One fiber is attached to a nearby slit-lamp microscope; the other extends approximately 70 m and can be connected to either an operating microscope or an endophotocoagulation probe. An electrically-operated mirror inside the machine controls which of the two fibers the laser beam passes through. Separate control boxes for each fiber permit direct regulation of the photocoagulation process in all situations.