Contribution of autogeneic membranous bone chips and bone paste to healing of rabbit skull defects.

In skeletal surgery, bone chips and bone paste are often used to facilitate bony repair. However, no comparative investigation between these forms of bone graft implantation has been undertaken. In this study four trephine skull defects were produced in each of 14 adult rabbits and inlays of bone paste and two separate amounts of bone chips were then implanted in each animal. The results were compared relative to a control defect and assessed by gross inspection, light microscopy, and contact radiography after periods of 4 and 15 wk. Bone chips offered only minor advantages over controls in the defects investigated and differences in bony regeneration between the diversified amounts of bone chips were negligible. After bone paste implantation, a cellular and mature bone was rapidly produced. The clinical significance of these findings is discussed.     

Low Serum Retinol Is Associated with Increased Severity of Measles in New York City Children

Children with no known prior vitamin A deficiency exhibited a significant decline in their serum retinol levels during the acute phase of measles. This decline in circulating retinol was associated with increased duration of fever, higher hospitalization rates, and decreased antibody titers.     

Ziprasidone in the treatment of mania in bipolar disorder

Ziprasidone is an atypical antipsychotic with a unique receptor-binding profile. Currently, ziprasidone is approved by the US Food and Drug Administration for the acute treatment of psychosis in schizophrenia and mania in bipolar disorder. When compared to certain other atypical antipsychotics, ziprasidone appears to have a relatively benign side effect profile, especially as regards metabolic effects eg, weight gain, serum lipid elevations and glucose dysregulation. Taken together, these data suggest that ziprasidone may be a first line treatment for patients with bipolar mania. However, ziprasidone is a relatively new medication for which adverse events after long-term use and/or in vulnerable patient populations must be studied. Unstudied areas of particular importance include the efficacy and safety of ziprasidone in the treatment of bipolar depression and relapse prevention of mania as, well as in the subpopulations of pregnant women, the elderly and pediatric patients. The emergence of mania in patients taking ziprasidone is another topic for further study.     

Effect of olanzapine treatment on platelet glutamine synthetase-like protein and glutamate dehydrogenase immunoreactivity in schizophrenia.

According to contemporary views, the glutamatergic system is implicated in the pathogenesis of schizophrenia, and atypical neuroleptics exert their effects (at least partially) through the glutamatergic system. Immunoreactive glutamate-metabolising enzymes, such as glutamine synthetase-like protein (GSLP) and two glutamate dehydrogenase isoenzymes (GDH), have been discovered in human platelets. The amount of GSLP in the platelets of 40 chronic patients with schizophrenia was found to be significantly higher than in 33 controls (consistent with our previous finding of increased amounts of GSLP in the prefrontal cortex of chronic schizophrenia patients). Moreover, survival analysis of the group of patients treated with olanzapine for 28 weeks showed that the larger amount of GSLP measured in platelets before treatment, the shorter the treatment time needed to achieve a positive clinical response (defined a priori as > or = 20% reduction in PANSS total score from the initial level before the treatment). Hence, GSLP level may serve as a predictor of the treatment duration to achieve a positive outcome with olanzapine. Both GSLP and GDH were found significantly changed in the course of treatment; hence, treatment with olanzapine influences the amounts of glutamate-metabolising enzymes in the platelets of chronic schizophrenia patients.     

A potentially deleterious role of IGFBP-2 on bone density in aging men and women.

The role of the IGFs and IGFBPs on age-related changes in BMD in adult men and women is not well understood. Studying an age-stratified community based sample of 344 men and 276 women, we found higher IGFBP-2 levels to be associated with lower BMD. IGFBP-2, which increases with age in both men and women, was the strongest, most consistent predictor of BMD among the IGF/IGFBPs studied. INTRODUCTION: Insulin-like growth factors (IGFs) and their binding proteins (IGFBPs) are important regulators of tissue growth and metabolism, but their association with BMD in adult men and women is controversial. MATERIALS AND METHODS: In an age-stratified, random sample of the community population, we examined the role of serum levels of IGF-I, IGF-II, and IGFBP-1, -2, and -3 on BMD of the proximal femur (total hip), lateral spine, midshaft, and ultradistal radius as measured by DXA. We explored the association before and after adjustment for potential confounders, including age, bioavailable estradiol and testosterone, sex hormone binding globulin (SHBG), and measures of total fat and skeletal muscle mass. RESULTS: We studied 344 men (age, 23-90 years) and 276 women (age, 21-93 years; 166 postmenopausal) not on hormone replacement or oral contraceptives. In both men and women, IGF-I and IGFBP-3 levels fell with advancing age, whereas IGFBP-2 levels tended to rise with age. There was an inverse association of IGFBP-2 with BMD at most skeletal sites in men and both premenopausal and postmenopausal women, whereas lower IGF-I and IGFBP-3 were associated with lower BMD in men and postmenopausal women only. Lower IGF-II was associated with lower BMD in men only. There were no associations between IGFBP-1 and BMD in either sex. After adjustment for age, in most cases, we found no further associations between IGF-I, IGF-II, or IGFBP-3 and BMD. In contrast, after age adjustment, higher IGFBP-2 remained a predictor of lower BMD in men and postmenopausal women at all sites except for the lateral spine (for men: r = -0.21, -0.20, and -0.19, all p < 0.001; and for postmenopausal women: r = -0.34, -0.24, and -0.25, all p < 0.01, for the total hip, midshaft, and ultradistal radius, respectively). IGFBP-2 remained an independent negative predictor of BMD in men, postmenopausal women, and all women combined after additional adjustment for bioavailable sex steroids, but not at all sites after adjustment for SHBG and muscle mass. In premenopausal women, IGFBP-2 had similar associations as seen in postmenopausal women, but they were weaker and not statistically robust. CONCLUSIONS: Among the IGF/IGFBPs in our study, IGFBP-2 was a key negative predictor of BMD among men and women, particularly postmenopausal women. Our findings suggest a potential role of the IGF/IGFBP system in regulating bone loss in aging men and women and identify a previously under-recognized, potentially deleterious role for IGFBP-2, a known inhibitor of IGF action that increases with age in both sexes. Whether the action of the IGF/IGFBP system on bone metabolism is mediated partly through its effects on muscle mass or SHBG deserves further study.     

Production of Ac-225 for cancer therapy by photon-induced transmutation of Ra-226.

The increasing application of Ac-225 for cancer therapy indicates the potential need for its increased production and availability. The production of Ac-225 has been achieved using bremsstrahlung photons from an 18 MV medical linear accelerator (linac) to bombard a Ra-226 target. A linac dose of 2800 Gy produced about 64 microCi of Ra-225, which decays to Ac-225. This result, while consistent with the theoretical calculations, is far too low to be of practical use. A more powerful linac is required that runs at a higher current, longer pulse length and higher frequency for practical production. This process could also lead to the reduction of the nuclear waste product Ra-226.