Seasonal variation in serum levels of vitamin D metabolites and parathormone in geriatric patients with fractures in Southern Israel.

In 41 geriatric patients with long bone fractures, a seasonal variation was observed in the serum levels of 25-hydroxyvitamin D (25-OH-D), 1,25-dihydroxyvitamin D [1,25(OH)2D], 24,25-dihydroxyvitamin D [24,25(OH)2D] and parathormone (PTH). The serum concentrations of vitamin D metabolites correlate positively, while that of PTH correlates negatively with day length and global solar radiation in southern Israel. Our data suggest that the higher serum levels of vitamin D metabolites during the summer suppress PTH secretion. During the winter, the reduction of serum levels of vitamin D metabolites due to decreased endogenous production was accompanied by an increase in serum PTH levels.

Parathormone, calcitonin, and vitamin D metabolites during normal fracture healing in geriatric patients.

In order to study the role of calcium-regulating hormones during callus formation in elderly patients, serum levels of parathormone (PTH), calcitonin (CT), 25-hydroxyvitamin D [25-OH-D], 1,25-dihydroxyvitamin D [1,25(OH)2D], 24,25-dihydroxyvitamin D [24,25(OH)2D], and calcium (Ca) were determined in 41 patients with fractures of long bones, primarily hip fractures. The parameters were measured on admission and after eight weeks. There were almost no changes in hormone serum levels during bone repair, except for a decrease in serum levels of 1,25(OH)2D from 25.3 +/- 2.3 pg/ml on admission to 21.0 +/- 2.0 pg/ml eight weeks later (p less than .001). Patients with fractures compared to normal elderly humans have lower serum levels of PTH (0.99 +/- 0.06 ng/ml versus 1.88 +/- 0.34 ng/ml; p less than .001), 25-OH-D (10.7 +/- 1.0 ng/ml versus 17.1 +/- 1.8 ng/ml; p less than .001), and Ca (9.1 +/- 0.1 mg% versus 9.7 +/- 0.1 mg%; p less than .001) and higher serum levels of 1,25(OH)2D (25.3 +/- 2.3 pg/ml versus 17.1 +/- 2.3 pg/ml; p less than .001). Female patients have lower serum levels of 24,25(OH)2D compared to males (1.65 +/- 0.15 ng/ml versus 2.06 +/- 0.29 ng/ml; p less than .05). A similar trend was noted in serum CT levels during callus formation (0.12 +/- 0.02 ng/ml versus 0.16 +/- 0.02 ng/ml; p less than .05). Patients with subcapital fractures of the femur have significantly lower serum levels of all vitamin D metabolites on admission, compared with patients suffering from extracapsular fractures.(ABSTRACT TRUNCATED AT 250 WORDS)

Mineral and endocrine metabolism during fracture healing in dogs.

The blood levels of parathormone (PTH), calcitonin (CT), vitamin D metabolites, calcium, phosphate, magnesium and alkaline phosphatase (AKP) were determined in 13 young dogs with experimental fractures of long bones. The parameters were measured before the fracture and during healing until the appearance of an early callus. Serum Ca levels were significantly reduced immediately after the fracture (10.95 +/- 0.30 mg/dl to 10.25 +/- 0.25 mg/dl; p less than 0.05). Significant rises in serum levels of PTH (0.99 +/- 0.10 ng/ml to 1.57 +/- 0.22 ng/ml; p less than 0.01); CT (0.14 +/- 0.01 ng/ml to 0.18 +/- 0.01 ng/ml; p less than 0.05); 24,25-dihydroxyvitamin D (13 +/- 2 ng/ml to 19 +/- 3 ng/ml; p less than 0.01) and AKP (153 +/- 24 U/l to 211 +/- 26 U/l; p less than 0.01) were noted during fracture repair. A reduction in serum levels of 25-hydroxyvitamin D (22 +/- 2 ng/ml to 15 +/- 1 ng/ml; p less than 0.001) was noted at the same time. The parameters returned or tended to return to normal levels during callus development. The data demonstrate the changes in levels of Ca-regulating hormones in response to bone injury. This suggests that CT and 24,25-dihydroxyvitamin D (24,25-(OH)2-D) can be associated with the process of callus formation.

The influence of age and sex on blood levels of calcium-regulating hormones in dogs.

In order to study age- and sex-related changes in calcium-regulating hormones, serum levels of parathormone (PTH), calcitonin (CT), and vitamin D metabolites were determined in 20 young dogs and 11 old dogs. A highly significant increase in serum levels of PTH was observed in old dogs (1.65 +/- 0.09 ng/ml versus 1.05 +/- 0.09 ng/ml in young animals) (p less than 0.001). Serum levels of 25-(OH)-D were significantly decreased in old dogs (11.24 +/- 2.03 ng/ml compared to 20.59 +/- 1.57 ng/ml in young dogs) (p less than 0.001). No significant differences in serum levels of 1,25-(OH)2-D, 24,25-(OH)2-D, and CT were found between young and old dogs. Serum CT levels were higher in males, especially in old animals. Young females had significantly higher serum levels of 25-(OH)-D than males. It seems that for some reason old dogs are in a relative state of vitamin D deficiency and hyperparathyroidism, which suggests the cause of skeletal alterations related to aging. A similar situation is observed in human geriatric patients.

Hormonal control of fracture healing in a dog with chorea.

An experimental fracture in a dog with chorea was found to heal faster, and with a larger callus, than normal. Serum levels of parathormone (PTH), calcitonin (CT) and vitamin D metabolities were determined during callus formation. Serum concentrations of vitamin D metabolites were lower from the beginning while serum CT levels were higher compared to normal dogs. A massive increase in serum levels of 24,25-dihydroxyvitamin D was noted during the healing period. These results and observations suggest the existence of some disturbances in the secretion of hormones regulating calcium metabolism during bone repair where a nervous system lesion exists.

Naloxone-precipitated withdrawal: a method for rapid induction onto naltrexone.

We examined naloxone-precipitated withdrawal as a means for rapid opiate detoxification and induction onto naltrexone. In 29 patients dependent on methadone (5 to 20 mg/day), abstinence was precipitated by an injection of naloxone. Repeated injections of naloxone were given subsequently until symptoms of abstinence were no longer induced. Successive injections induced less intense withdrawal assessed by vital signs and ratings on abstinence scales. The most rapid procedure consisted of 1.2 mg naxolone every 30 min for 3 to 6 hr, for 3 to 6 hr, followed by hourly increasing doses of naltrexone. This procedure allowed transition from opiate dependence to naltrexone maintenance (50 to 100 mg/day) within 48 hr. The results are consistent with assumptions that antagonists actively displace opiates from receptor sites.

Acute systemic effects of cocaine in man: a controlled study by intranasal and intravenous routes.

Nineteen healthy volunteer subjects who regularly administered cocaine to themselves were given placebo and 10 and 25 milligrams of cocaine hydrochloride intravenously and intranasally. A dose of 100 milligrams of cocaine was administered only by the intranasal route. By this route 10 milligrams of cocaine produced no changes different from placebo, and 25 milligrams of cocaine produced physiologic changes only in systolic blood pressure. The 100-milligram dose given intranasally and all of the doses given intravenously produced significant dose-related physiologic and subjective responses.

Short-term effects of naltrexone in 155 heroin ex-addicts.

The narcotic antagonist naltrexone was administered for periods of up to 8 months to a total of 155 patients at a dose of 40-200 mg per day. The antagonistic effect of naltrexone was tested by injections of heroin. Eighty milligrams of natrexone was effective for 48hr. The antagonistic effect decreased at 72 hr after the administration of 120-200 mg of naltrexone. Laboratory tests indicated no signs of toxicity. Naltrexone may elicit an increase in blood pressure and opigastric pain. Neither of these side effects appear clinically important. No signs of dependence on naltrexone were detected. These results suggest that naltrexone may be useful for clinical treatment of opiate dependence.

Evaluation of propranolol in opiate dependence.

Among the increasing number of recent reports of the use of beta-adrenergic blocking drugs for a variety of psychiatric disorders is a series concluding that propranolol hydrochloride is efficacious in the treatment of opiate dependence. These reports were based on clinical observations of outpatient addicts in an uncontrolled situation. In order to validate these findings, we carried out a series of controlled, double-blind studies with hospitalized volunteers. The results of our studies do not confirm the previous reports. Propranolol neither relieved nor precipitated opiate withdrawal in subjects dependent either on dihydromorphinone hydrochloride or on heroin. It did not effectively block heroin-induced euphoria in dependent or nondependent subjects. In addition, there was no effect on the pattern of self-administration in opiate-dependent subjects, whether they were maintained on propranolol or placebo.

l-Alpha-acetylmethadol (LAAM): prognostic considerations.

The authors studied the responses of 28 adult male volunteers who were openly changed from methadone to l-alpha-acetylmethadol (LAAM) maintenance. They found that patients who had been receiving middle-range doses (50-70 mg) of methadone required a significantly lower mean increase in LAAM than patients who had been receiving either high or low methadone doses and that the patients who accepted LAAM differed significantly from those who did not in MMPI 2-point-code ratings and mean social adjustment scale scores. These findings may provide prognostic indicators for response to LAAM, a possible alternative to methadone.

Behavioral measurement of neural poststimulation excitability cycle: pain cells in the brain of the rat.

A new technique in which elicited behavior of the freely moving rat is used to measure the poststimulation excitability cycle of the central neurons mediating that behavior has been adapted from accepted methods of neurophysiology. A continuous train of pairs of brief pulses was delivered to pain systems in the midbrain. Rate of lever pressing to achieve 3-second rests from this stimulation was measured as a function of the interval separating the pulses within pairs. Evidence for latent addition, absolute refractory period, temporal summation, and adaptation was demonstrated. Obtained relationships suggested that three sets of fibers may carry the aversive signal and that synaptic integration of pain in the brain may be related to Stevens' power law functions.