Monolayer cultures of normal human bone cells contain multiple subpopulations of alkaline phosphatase positive cells

Summary Cytochemical staining of normal human bone cells in monolayer cultures for alkaline phosphatase (ALP) indicated that the cultures contained mixed-cell populations. Time course evaluations of the cytochemical staining revealed, in addition to the ALP-negative cell population, at least two subpopulations of ALP-positive human bone cells with different levels of ALP. A cytochemical method has been developed which separates the ALP-positive cells into high and intermediate ALP subpopulations. In this method, human bone cells were stained for ALP using an azo-dye method and incubating at 4°C for 10 and 30 minutes, respectively. We defined the cell population that stained positively for ALP at 10 minutes as strong ALP-positive cells, and both strong and intermediate cells were stained at 30 minutes. The intermediate cells were determined from the difference between the values at the two time points. The intra- and interassay variations of the assay, with the same investigator in blinded investigations, were both less than 10% and the interobserver variation was approximately 25%. Analysis of the distribution of ALP levels in cells with a laser densitometer confirmed the presence of at least three cell subpopulations. 1,25(OH)₂D₃ treatment increased the proportions of both ALP-positive cell populations, whereas TGF-beta treatment increased only the intermediate ALP-positive cell population. On the contrary, fluoride increased the proportion of the strong ALP cells, and IGF-1 had no effect on the proportions of either ALP-positive subpopulation. When the ALP-specific activity was compared with the percentage of each ALP-positive subpopulations for the cells treated with effectors, the ALP-specific activity correlated with the total ALP-positive and with the strong ALP-positive populations but not with the intermediate ALP-positive subpopulation. In summary, this study represents the first evidence that normal human bone cells in monolayer cultures contained at least two subpopulations of ALP-positive cells, and that bone cell effectors could have differential effects on each cell population.     

Potentiation of cholinergic activity with pyridino[1,2-a]imidazo[5,4-b]indole: in vitro studies

1. Effects of a novel imidazoindole derivative on cholinergic function were studied in isolated tissue preparations. 2. The compound demonstrated a dose-dependent (10(-11)-10(-9) potentiation (20-60%) of acetylcholine induced tension in guinea pig ileal tissue. 3. Increases in the size of end-plate potentials and nerve evoked muscle twitches were observed in frog nerve-skeletal muscle preparations. 4. Cholinesterase activity was not inhibited. 5. The results suggest that the compound has actions at the post-synaptic muscarinic receptor complex in smooth muscle and causes pre-synaptic increases in ACh release at the neuromuscular junction.     

Effects of hypothermia on testicular ischemia

The ischemic effects of prolonged testicular torsion have been well documented; however, prevention or arrest of the damaging effects of prolonged ischemia has been incompletely studied. Two groups of Sprague-Dawley rats were subjected to varying lengths of bilateral testicular ischemia. Group I underwent normothermic ischemia for two, four, and six hours. Likewise, Group II underwent similar time periods of ischemia, however, after thirty minutes of normothermic ischemia the scrotum of each animal was placed into an ice bath maintained at 4C. Two weeks postoperatively, bilateral orchiectomy was performed. Histology of the testes of the two groups was compared. Neither group revealed significant destruction of the germinal epithelium after two hours of ischemia. Group I revealed only 25% preservation of the germinal epithelium at four hours and only 8% preservation at six hours of ischemia. In contrast, Group II which received ice showed 90% preservation of germinal epithelium at four hours and 85% preservation at six hours of ischemia. We conclude that external ice application significantly preserves seminiferous tubules at four and six hours of ischemic injury in the rat testicle.     

Functional diagnosis of early arthroses of the extremities

Patient history and clinical examination are important for the diagnosis of degenerative joint disease. Here the typical statements of a patient suffering from early osteoarthritis are described and, as far as possible, explained. The joint in question must be systematically examined. Furthermore, the neighboring joints and soft-tissue structures, i.e., muscles, tendons etc., should be examined and evaluated with respect to their importance in hindering the functional chain. The neuroreflectory mechanisms involved herein are described.     

Head lice in Israeli children: parents' answers to an epidemiological questionnaire

BACKGROUND: The aim was to determine the influence of the socioeconomic status of the family and the hygienic practices in the home on the prevalence of head lice infestation in children. METHODS: The study was carried out by analyzing the answers to a standardized epidemiological questionnaire given to parents of school children aged 4-17 in Bet Shemesh, a medium-sized urban town 25 km from Jerusalem. RESULTS: Of 3,000 questionnaires distributed, 958 (31.9%) were completed and returned. The majority of the children (72.4%) had been previously infested with lice. Half of them had other family members, mainly brothers and sisters, who had been infested in the past with lice. In 97.5% of the families the mother was responsible for examining the children for lice, and for carrying out treatment when infestation was present. An association was found between presence of lice infestation and mother's education, age of child, and frequency of shampooing, combing, and examination for lice. There was no association between infestation rates and mother's country of origin, crowding in the home, and the sharing of combs, brushes, hats, scarves, towels, and clothes. CONCLUSIONS: There is evidence that the incidence of lice infestation depends on the hygienic practices in the home rather than on the socioeconomic status of the family or sharing of personal articles among family members.     

The effect of metronidazole on TPN-associated liver dysfunction in neonates

The effect of metronidazole (MNZ) on hepatic dysfunction associated with total parenteral nutrition (TPN) in neonates was investigated. Neonates receiving TPN for more than 2 weeks were divided into three groups. In group 1, TPN was given alone, in group 2, 25 mg/kg/d of MNZ was administered intravenously for the first 2 weeks of TPN, and in group 3, 50 mg/kg/d of MNZ was given for the first 3 weeks of TPN. Several parameters of liver function tests (LFTs) during the first 4 weeks of TPN were compared among these three groups. There was no significant difference of these parameters between group 1 and group 2. Although there was no significant difference of alkaline phosphatase, gamma-glutamyl transpeptidase, direct bilirubin, and total bile acid between groups 1 and 3, transaminase (glutamic oxaloacetic, glutamic pyruvic) of group 3 remained significantly lower than those of group 1. In conclusion, the administration of MNZ 50 mg/kg/d for 3 weeks, at least, prevented the elevation of transaminase during TPN in neonates, suggesting the possible involvement of intestinal anaerobic flora in the pathogenesis of TPN-associated liver dysfunction.     

Uses and risks of drainage following elective colon resection. A prospective, randomized and controlled clinical study

The results of a controlled randomized and prospective clinical study including 113 patients from March 1987 until August 1988 showed that prophylactic drainage in elective resection for cancer of the colon was not necessary. 60 patients received a drain, 53 patients were not drained. The drain turned out to be ineffective even concerning its expected function of draining intraabdominal fluid: its diagnostic and therapeutic value failed in clinical practice. The rate of surgical complications--i.e. anastomotic leakage, impaired wound healing and relaparotomy--was significantly higher in the drained group. In elective colon resection the use of a drain as a routine procedure cannot be recommended.     

Serum bone-gla protein after fracture

Serum bone Gamma-carboxyglutamic acid (bone-gla) protein (BGP), a marker of bone formation, was measured in serial blood samples drawn from 14 patients who had fractured at least one of their tibial or femoral diaphyses and from two other patients who had sustained major trauma without fracture but who had been immobilized. A total of 85 samples were taken and analyzed during the first three months after the fractures occurred. Serum BGP significantly increased and positively correlated with the time that had elapsed after the fracture, with an average twofold increase after two months. The fracture site and the duration of immobilization had no influence on the serum BGP levels. Serum BGP levels from the two non-fractured cases increased in the first two weeks with no subsequent consistent trend. These data suggest that serum BGP increases one to two months after a major fracture, possibly as a manifestation of bone repair. Further studies are required to determine the potential clinical value of serum BGP in the management of such patients.