mu-Opioid agonists stimulate growth hormone secretion in immature rats.

The purpose of the present study was to evaluate the opioid receptor subtype mediating opioid modulation of growth hormone (GH) secretion during ontogeny. The mu-agonist morphine and the kappa agonist U50,488 caused a stimulation and inhibition of GH secretion, respectively, on postnatal day 10. Studies on postnatal days 2, 5, 10, 15 and 20 showed that kappa-inhibition could be observed as early as day 2, but substantial mu-stimulation was not observed until postnatal day 10. Intracerebroventricular (i.c.v.) administration of the mu-selective peptide [D-Ala2-NMe-Phe4-Gly-ol]-enkephalin (DAMGO) elicited a marked rise in GH secretion, while administration of the delta-agonists [D-pen2D-pen5]-enkephalin (DPDPE) or deltorphin II caused only a minor and non-dose-related rise in GH secretion in neonatal rats. The relative importance of mu- and delta-receptors in stimulating GH secretion was also studied in older pups (day 20). i.c.v. administration of DAMGO stimulated GH secretion, while neither DPDPE nor deltorphin II consistently increased GH secretion. Furthermore, peripheral administration of either morphine or the highly selective mu-agonist sufentanil elicited marked GH secretion on postnatal day 20, but only combined administration of the mu-antagonist beta-funaltrexamine (beta-FNA) and the delta-antagonist naltrindole substantially diminished these responses. These results suggest that both mu- and kappa-opioid receptors are involved in the regulation of GH secretion in neonatal rats. While delta-receptors do not play a prominent independent role in this response, they may act synergistically with mu-receptors in producing stimulation.

The effect of exercise on the presence of leukocytes, erythrocytes and collagen fibers in skeletal muscle after contusion.

OBJECTIVE: To determine the comparative rate of resolution of a contusion resulting from mechanical trauma to skeletal muscle, as a function of one of four exercise regimens. DESIGN: Randomized control trial. The four exercise regimens were: running with its onset immediately after injury, running with a 72 hr delay after injury, swimming with immediate onset, or swimming with a 72 hr delay. Control did not exercise. SETTING: Small-animal laboratory. PARTICIPANTS: Male Sprague-Dawley rats. INTERVENTION: A small animal traumatizing machine applied to the biceps femoris. MAIN OUTCOME MEASURES: The rate of contusion resolution was determined by a manual count of erythrocytes, leukocytes and collagen fibers in the contusion, and the data were analyzed using analysis of variance. RESULTS: Exercise of any type produced a greater decline in erythrocyte count (28.2% after 32 days vs. control) than no exercise. Immediate onset of any of the exercise regimens after injury resulted in a greater decline in erythrocyte count (32.7% after 32 days vs. control) and in leukocyte count (17.3% after 32 days vs. control) than delayed onset. Running with either immediate or delayed onset of exercise after injury produced a greater decline in erythrocyte count (36.2% after 32 days vs. control) than swimming. Running with its onset immediately after injury produced the greatest overall rate of decrease in erythrocyte count (44.8% after 32 days vs. control), and the second greatest overall rate of decrease in leukocyte count (15.0% after 32 days vs. control). CONCLUSIONS: Running with immediate onset is the regimen of choice. Any of the given exercises is preferable to no exercise, immediate onset of exercise is preferable to delayed onset, and running is preferable to swimming.

Does the Q angle reflect the force on the patella in the frontal plane?

BACKGROUND AND PURPOSE: The quadriceps femoris muscle angle (Q angle) is used to reflect the quadriceps femoris muscle's force on the patella in the frontal plane. We found no studies, however, that validate this assumption. The purpose of this study was to determine whether the Q angle can be used to represent the force on the patella in the frontal plane. SUBJECTS: Seven lower extremities from four male cadavers were dissected and investigated. METHODS: We devised a model in which the line of action of quadriceps femoris muscle's resultant force was calculated in the frontal plane on the seven lower-extremity specimens. We then compared these calculations with the Q angles from the same cadaver specimens. The differences between the measured and calculated Q angles were tested for significance using a paired t test. In addition, we calculated a simple linear regression to test the relationship between the calculated and measured Q angles. RESULTS: Our data showed that the angle for the average resultant force of the quadriceps femoris muscle was 3.90 degrees greater (P = .0003) than the measured Q angles. A significant relationship (r = .919, P = .0035); however, was found between the measured and calculated Q angles. CONCLUSION AND DISCUSSION: The Q angle, as measured in clinical practice, appears to reflect the angle of the resultant quadriceps femoris muscle force. We believe, however, that this measurement is significantly less than the actual quadriceps femoris muscle force vector and underestimates the lateral force on the patella.

Parameters and comparisons of the quadriceps angle of college-aged men and women in the supine and standing positions.

The purpose of this study was to determine normal, mean quadriceps angles (Q angles) for college-aged men and women, and to compare Q angles measured in the supine and the standing positions. The Q angles of 269 men and 257 women were measured in both positions by use of a specially modified goniometer. The mean Q angle for men was 12.7 degrees in the supine position and 13.6 degrees in the standing position; for women the mean Q angle was 15.8 degrees in the supine position and 17.0 degrees in the standing position. All of these differences were statistically significant. We calculated the incidence of an abnormally high Q angle, and will discuss the implications of our findings.

Influence of local steroid injections on traumatized tendon properties. A biomechanical and histological study.

We investigated the effects of peritendon injections of hydrocortisone acetate on the separation force required to completely avulse a posttraumatized Achilles tendon of the adult male rat. One hundred thirty-five rats were randomly assigned to 3 groups and subsequently traumatized, treated, and sacrificed. One group was used to examine the effect of trauma; the second to examine effects of trauma and injections of hydrocortisone acetate on the tension to failure strength of tendons; the third group was the control group. Injected animals received one, three, or five injections of 0.10 cc (125 mg/ml) hydrocortisone acetate and were sacrificed 3, 6, or 9 weeks following initial injection. Experimental animals (anesthetized) were traumatized by dropping a weight onto the Achilles tendon. The tendon was tested in tension to failure employing a soft tissue linear disseminator. Histologic analysis using light microscopy was performed. We concluded that hydrocortisone acetate has no deleterious effect on the rat Achilles tendon as measured biomechanically or histologically.

Scoliosis screening of 3,000 college-aged women. The Utah Study--phase 2.

The purpose of this phase of the Utah study was to determine the prevalence of scoliosis in college-aged women over a three-year period. The subjects were 3,210 female college students (mean age = 19.7 +/- 2.1 years) from 34 states and 5 foreign countries. The majority (98.2%) of the students were Caucasian. Nearly 12% of the study sample (n = 380) demonstrated a visually assessed lateral deviation of the spine. This finding demonstrates a higher prevalence of scoliosis among an age group that has reached an age of growth cessation than the literature on scoliosis screening indicates. The college-aged students in this study demonstrated a higher prevalence of scoliosis than the national norm for a younger (10-15 years of age) group. This result suggests that scoliosis may develop later in life than has previously been reported and that physical therapists must become more proficient in conducting scoliosis screening programs.

Screening for musculoskeletal deviations--a challenge for the physical therapist. The Utah Study.

We conducted an on-site examination in selected middle and junior high schools in Utah to determine the incidence of selected musculoskeletal deviations. During a regular school year, we screened 4,670 children. The students we examined represented a random sample of students in the sixth through the ninth grades from a population of 81,047 students. Among the 2,192 boys and 2,478 girls examined, we noted a total of 10,551 postural deviations. Eighteen categories of deviations of the musculoskeletal system were examined visually. Lordosis was the most common postural deviation seen (45%), and torticollis was noted least commonly (0%). Scoliosis was noted in 7% of the total population, with a girl-boy ratio of 2:1. Both the lack of body postural awareness we observed among the children and the significant findings of this study should warrant initiation of more responsible educational programs in the public schools. An apparent need for a uniform statewide screening program was demonstrated.

Topically applied dimethyl sulfoxide. Its effects on inflammation and healing of a contusion.

This study investigated the effects of topically applied dimethyl sulfoxide (DMSO) to traumatized muscle of adult male rats. Eighty rats were randomly assigned to one of two groups and subsequently traumatized, treated, and sacrificed. One group was used to examine inflammation; the other, healing. Each group was further divided into an experimental group (70% DMSO and 30% distilled water) and a control group (100% distilled water); each group had five sacrifice times. Each treatment consisted of painting 1 ml of either the treatment or control solution on the contused tissue. The inflammation group received 15 additional treatments, 3 per day for the next 5 days. A three-phased, single blind, histologic examination was performed. The principle findings were: significantly fewer healing cells were present in the experimental group than in the control group during the period inflammation was examined, and no significant difference existed between the experimental and control groups during the period healing was examined.

Effects of Strength Training on Muscle Development in Prepubescent, Pubescent, and Postpubescent Males.

In brief: Thirty-three prepubescent, pubescent, and postpubescent males participated in a nine-week resistive exercise program to test the hypothesis that pubescent males respond better to strength training than older and younger groups do. Before and after the program, the subjects' strength in elbow and knee flexion and extension was tested bilaterally on a dynamometer at two velocities. The posttest showed that all of the subjects gained strength in elbow flexion and extension and knee extension but not in knee flexion. The prepubescent group showed significantly greater gains than the others on three of the 16 tests, but in no case did the pubescent group show significantly greater gains.

Small-animal traumatizer.

Clinical research, particularly among traumatized musculoskeletal patients, has been greatly inhibited by a lack of uniformity in the intensity of the injury. That is, few patients present identical injuries with respect to intensity and degree of soft tissue damage. Hence, researchers have gone to the experimental animal to achieve uniformity to the wound. Few studies, however, have reported effective methods of uniform traumatization. A small-animal traumatizer was developed at Brigham Young University that has proved reliable in producing a uniform contusion of 177 mm2 on the lateral thigh of the anesthetized experimental animal. If the investigator seeks an experimentally induced hematoma that approximates contusions seen clinically, one that is unvarying in every sample, something not available in traumatized patients, the small-animal traumatizer may be an important addition to your laboratory.

Disodium cromoglycate compared with beclomethasone dipropionate in juvenile asthma.

In a double-blind controlled crossover trial of inhaled disodium cromoglycate and beclomethasone dipropionate in juvenile asthma, beclomethasone produced higher therapeutic scores but significantly so in only two indices--wheeze-free days and morning peak flow rates. Combined treatment offered no advantage over beclomethasone alone. No side-effects were noted. The findings confirm other studies of cromoglycate and a steroid aerosol (betamethasone 17-valerate) but disagree with the only other comparative trial of cromoglycate and beclomethasone, in which both were found equally effective.

Adrenocortical function during high-dose beclomethasone aerosol therapy.

Prolonged observation of eight steroid-dependent asthmatics show that the dose of beclomethasone dipropionate aerosol may be increased in some cases up to 2000 micrograms daily without significant impairment in the results of serial tetracosactrin tests of adrenocortical function. These findings contrast sharply with the results of such tests during oral prednisolone therapy.

Therapeutic Ultrasound: Its Effects on the lntegrity of a Nonpenetrating Wound*.

This study investigated the effect of ultrasound applied to traumatized muscle tissue of an adult male rat. Sixty-six rats were traumatized, treated, and sacrificed. The rats were assigned to one of 11 groups, to which experimental and control (two mock) ultrasound treatments were given at 3- and 7-minute time periods at 0.5 and 1.5 watts per square centimeter intensities (pulsed and continuous ultrasound). The rats were given a total of six treatments, once every other day three times a week. Treatments began on the third day following the receipt of a nonpenetrating wound on the right lateral thigh. The animals were subsequently analyzed histologically to determine the extent of healing cells present. The principal findings were as follows: 1) ultrasound intensities had a significant effect on healing, 2) there was no statistical difference between the overall means of the control and experimental groups, and 3) there was no difference between the pulsed and continuous modes of ultrasound or between treatment times.J Orthop Sports Phys Ther 1984;5(5):278-281.

Hormonal and metabolic effects of a pancreatic endocrine graft. Vascularized segmental transplantation in insulin-dependent diabetic patients.

A new modification of pancreas transplant technique, the vascularized segmental intraperitoneal graft without duct ligation, has provided reversal of insulin-dependent (type I) diabetes mellitus for as long as 2 years of comfortable life. Although the risks associated with immunosuppression remain high (two of the 12 patients have died of early postoperative infection), selected data are presented from six cases to show the following striking hormonal and metabolic results after transplantation and withdrawal of insulin: restoration of normal beta cell function as shown by 24-hour urine C-peptide excretion and acutely responsive serum insulin, restoration of normal suppressibility of plasma glucagon, elimination of ketosis and negative nitrogen balance, normal fasting plasma glucose and glycosylated hemoglobin, and normal or near-normal glucose tolerance. These results provide a standard for current explorations of new ways of treating insulin-dependent diabetes.