Reflex inhibition of the quadriceps after meniscectomy: lack of association with pain

We have examined the severity and duration of reflex inhibition of quadriceps activation after arthrotomy and meniscectomy, its relationship with pain, and the effect of local anaesthesia on this relationship. Fourteen men, on completion of medial meniscectomy by arthrotomy, received either 10 ml (B10 group) or 15 ml (B15 group) of 0.5% bupivacaine hydrochloride ('Marcaine Plain') into the knee, or no injection (control group). Reflex inhibition of quadriceps was measured as the percentage reduction, from the ipsilateral preoperative value, in the integrated surface electromyogram recorded during maximal voluntary isometric contractions with the knee in extension. Pain during each contraction was recorded on a linear analogue scale. Unoperated limbs showed no evidence of quadriceps inhibition. In the operated limbs, at 1-2 h post-operatively, controls had both severe inhibition (median = 62%) and severe pain on attempting a maximal quadriceps contraction. The B10 group had similar inhibition but less pain (P less than or equal to 0.005, Wilcoxon 2-sample, 1-tailed test). In the B15 group both inhibition (P less than or equal to 0.05) and pain (P less than or equal to 0.01) were less than in the controls. These effects of bupivacaine had been lost by 4-5 h post-operatively. At 3-4 days, inhibition was still severe (median = 75%) in all three groups of patients but pain was only mild or absent. At 10-15 days, median inhibition was still 35%, but there was little or no pain. We conclude that postmeniscectomy inhibition is not simply due to perceived pain but is due, at least in part, to stimuli from the knee.     

Is the outcome of in-vitro fertilization and embryo transfer treatment improved by spontaneous or surgical drainage of a hydrosalpinx?

A pilot study was designed to examine whether the outcome of embryo transfer in women with a hydrosalpinx might be improved by surgical drainage of the hydrosalpinx at the time of oocyte collection for in- vitro fertilization treatment. A comparative, controlled but retrospective analysis of the results was performed of all women with infective tubal damage aged <40 years old, who had ovulatory cycles, a normal uterus and a partner with normal spermatozoa. A standardized treatment regimen was used. A maximum of three embryos were transferred. Hydrosalpinx was defined by prior hysterosalpingography and/or laparoscopy with transcervical dye injection. A total of 237 embryo transfer cycles in women with hydrosalpinges (tubal distension not visible in 151, visible but not drained in 30 and drained in 56) were compared with 705 embryo transfer cycles in women with tubal disease but no hydrosalpinx. Results were analysed in the first three cycles but also separately in the first cycle to check for bias. Success rates were higher in the first cycle, but did not significantly influence overall differences. Implantation rates were significantly reduced overall in the hydrosalpinx group (8.0 versus 13.2% for controls; P < 0.001), being 8.3% (P < 0.01) in the subgroup without evident tubal distension and 7.5% (not significant) in the drained hydrosalpinx group. This study shows that tubal damage with distal occlusion is associated with a marked reduction in embryo implantation, even in the absence of obvious fluid distension. Surgical drainage of distended hydrosalpinges appears to offer no benefit.      

Psychosocial correlates of alcohol intake among women aged 45 to 64 years: The Framingham Study

This study of 749 women, aged 45 to 64 years, investigates the psychological, behavioral, and social correlates of alcohol intake. These data from the Framingham Study are uniquely based on a community sample of women, which results in a normative study of drinking behavior in women. Two measures of alcohol intake were utilized in these analyses: (1) the frequency of alcohol intake over 1 week and (2) drinking vs abstaining from alcohol. Among this sample of women, increased socioeconomic status, worrying about aging, and being easily upset were positively associated with frequency of alcohol intake. The rigid attitude scale was the strongest discriminating variable for drinkers vs nondrinkers. Older women were more likely to be nondrinkers compared to younger women, however, among older women, being a homemaker was significantly associated with increased alcohol intake. Contrarily, younger women who were homemakers were more likely to be abstainers than women employed outside the home. As would be expected, cigarette smoking was associated with drinking alcohol.This research is dedicated in fond remembrance to our friend and colleague Joseph Stokes III, M.D.     

The distribution of mucosal lymphoid nodules in the equine respiratory tract

Mucosal lymphoid nodules were identified within the equine respiratory tract by an acetic acid fixation technique. Nodules were identified in foetuses from nine months gestational age, and estimates of total and regional nodule populations were made in foetal, neonatal and adult horses. Nodules occurred at specific sites within the tract, which probably relate to areas where inhaled antigens accumulate. The largest populations of nodules occurred in the nasopharynx and larynx, with smaller numbers in the nasal cavity, trachea and bronchi. There was an age-related change in the size of these nodule populations, with an increase in number from late gestation to the neonatal period to early adulthood (up to 5 years of age), followed by a decrease in older adults.     

The role of prolactin and testosterone in mediating seasonal differences in the self-grooming behavior of male meadow voles, Microtus pennsylvanicus

Self-grooming in response to the odors of conspecifics is a form of olfactory communication among meadow voles. The amount of time meadow voles spend self-grooming when they encounter the odors of conspecifics varies seasonally, with males targeting the odors of reproductively active females only during the breeding season. Other odor related behaviors in male voles such as odor preferences for conspecifics and the attractiveness of their odors to conspecifics vary seasonally as well. For male meadow voles, these behaviors are mediated by seasonal variations in testosterone (T) and prolactin (PRL) titers. The objective of this study was to determine whether seasonal differences in the amount of time male meadow voles self-groom in response to odors of conspecifics are mediated by seasonal rhythms in their circulating T and PRL titers. We tested the hypothesis that high titers of both T and PRL are necessary for reproductively active (long-photoperiod; LP) males and sufficient for reproductively quiescent (short-photoperiod; SP) male voles to spend more time self-grooming in response to odors of LP females than to those of other conspecifics. Results of this study demonstrate that high titers of PRL and T are necessary for LP male meadow vole to self-groom more in response to odors of LP females as compared to those of other conspecifics, but were not sufficient to induce SP males to preferentially self-groom to odors of LP females. The endocrine control of self-grooming by LP males appears to depend upon high titers of both PRL and T, which matches the endocrine mediation of other odor related behaviors in male voles. In contrast, the endocrine tissues that underlie self-grooming in SP male meadow voles appear to be refractory to the effects of LP-equivalent titers of PRL and T.     

Hyperuricemia as a risk factor of coronary heart disease: The Framingham Study

Uric acid values were obtained on subjects of the original Framingham cohort at their fourth and 13th biennial examinations. The mean uric acid value for men was 5.0 mg/dl at the fourth examination and 5.7 mg/dl at examination 13 and was 3.9 mg/dl and 4.7 mg/dl, respectively, for women. This secular trend was due to both "laboratory drift" and increasing use of diuretics. Serum uric acid values were consistently higher in subjects of both sexes who were taking antihypertensive drugs at both examinations. Serum uric acid values correlated with systolic and diastolic blood pressure in both sexes; the relationship was stronger in women than in men and for systolic than for diastolic pressure. Correlations were stronger at examination 4 than at examination 13 when more antihypertensive treatment was used. Examination 4 serum uric acid predicted the subsequent development of coronary heart disease, in general, and myocardial infarction, in particular, but not angina pectoris. The uric acid relationship with myocardial infarction was equally strong in both sexes, even correcting for antihypertensive treatment. However, in multivariate analysis, including age, systolic blood pressure, relative weight, cigarette smoking, and serum cholesterol, serum uric acid did not add independently to the prediction of coronary heart disease.     

The effects of poly chlorinated biphenyls and methylmercury,singly and in combination on mink. II: Reproduction and kit development

Adult ranch-bred mink (Mustela vison) were fed diets containing either 0, 1.0 g/g polychlorinated biphenyls (PCB) (Aroclor^® 1254), 1.0 g/g methylmercury (MeHg), a combination of 1.0 g/g PCB plus 1.0 g/g MeHg, or 0.5 g/g PCB plus 0.5 g/g MeHg. Fertility of adult male mink, percentage of females whelped or number of kits born per female were not affected by the treatments. However, growth rate of kits nursed by mothers exposed to 1.0 g/g PCB was significantly reduced. There was a synergistic effect of PCB and MeHg which reduced kit survival in groups receiving both chemicals simultaneously. Kit survival to weaning in the control, 0.5 g/g PCB/MeHg, and 1.0 g/g PCB/MeHg groups was 72.0%, 62.7% and 35.8%, respectively. The results suggest that growth and survival of mink kits are adversely affected at dietary levels of PCB and MeHg currently present in some environments.     

Measurement of axial rotation of vertebrae in scoliosis

The authors report a radiographic method for measuring the axial rotation of vertebrae in degrees and its use in 99 patients with adolescent idiopathic scoliosis. The offset of the pedicle images from the vertebral body center and a "depth" estimate measured radiographically in a population of patients with scoliosis permitted calculation of axial rotation by means of a simple mathematical formula. It was found that measurements of vertebral rotation can be made clinically from single-plane radiographs with a standard deviation of 3.6 degrees (95% confidence limit +/- 7.1 degrees) based on a study of known rotations of a radiographic phantom, and with a standard deviation of 2.44 degrees (95% confidence limit +/- 4.8 degrees) based on comparisons with three-dimensional measurements of the orientation of each vertebra derived from low-dose stereo films of a group of patients. Measurements from clinical films are unlikely to be made more accurately than this, because of inherent geometric constraints.