Effects of cryopreservation on CD4+ CD25+ T cells of HIV-1 infected individuals

The role of T regulatory cells (Tregs) in human immunodeficiency virus (HIV)-1 infection, although not entirely clear, has recently been highlighted. Despite their lack of specificity, fluorochrome-labeled CD4 and CD25 antibodies are common flow cytometric reagents used to identify these cells with immunosuppressive potential. Cryopreservation has previously been shown to alter the proportions of lymphocytes with certain phenotypes expressed in peripheral blood mononuclear cells (PBMCs). The aim of this study was to assess the effect of cryopreservation on CD4+ CD25+ T cells in PBMCs from HIV-1+ individuals to guide the design of future studies on Tregs. We recruited 30 HIV-1+ individuals and nine healthy controls. CD25 expression in CD4+ T cells was compared between fresh and frozen/thawed PBMC samples from the same time point. In this study, cryopreservation significantly decreased the proportion of CD4+ CD25+ T cells in PBMC samples from HIV-1 infected subjects. This finding suggests that studies of CD4+ CD25+ T cells should be carried out on fresh samples to avoid bias introduced by cryopreservation.     

Influence of defect on the electrical and optical properties of A-site non-stoichiometry Ca0.67La0.22□0.11Ti(1−x)CrxO3−δ perovskite

An investigation of the dielectric dispersion, electrical properties, scaling behavior and optical defects of Ca_0.67La_0.22□_0.11Ti_(1−x)Cr_xO_3−δ (CLT_(1−x)Cr_x) with x = 0 and x = 0.1 compositions is presented. The square in the formula is attributed to a vacancy in A-site. Relaxation phenomena were studied with dielectric and modulus formalism, while, the conductivity mechanism was investigated using electrical conductivity. A high permittivity of around 10⁴, low dielectric loss and low electrical conductivity of around 10⁻³ S cm⁻¹ for Ca_0.67La_0.22TiO₃ (CLT) was observed. These values make this composition interesting for microelectric applications. A comparison between the Z′′ and M′′ indicated that the short-range carrier motion dominates at low temperature and becomes less localized at high temperature. The optical defects of CLT and Ca_0.67La_0.22Ti_0.9Cr_0.1O₃ (CLT_0.9Cr_0.1) were studied by electron paramagnetic resonance (EPR) spectroscopy. The results suggest the formation of a [TiO₆]⁹⁻ center, a (Ti³⁺–V_O) center, and dipole defect for CLT compound and Cr³⁺–V_O center defect for CLT_0.9Cr_0.1 compound. These defects are the source of the in-gap electron traps, which improve the optical properties of CLT_(1−x)Cr_x and hence make it an interesting optical material for different applications.

An investigation of the real part of permittivity for the compositions (a) x = 0 and (b) x = 0.1 solid solution Ca_0.67La_0.22□_0.11Ti_(1−x)Cr_xO_3−δ ceramics.     

Efficacy and tolerability of intravenous ibandronate injections in postmenopausal osteoporosis: 2-year results from the DIVA study

OBJECTIVE: An effective and well tolerated intravenous (IV) bisphosphonate could provide a new treatment method for patients with osteoporosis. The Dosing IntraVenous Administration (DIVA) study was designed to identify the optimal ibandronate IV injection schedule for the treatment of postmenopausal osteoporosis by comparing the efficacy and tolerability of 2- and 3-monthly injections with the previously evaluated daily oral ibandronate regimen. We report the effects on lumbar spine and proximal femur bone mineral density (BMD) and bone resorption markers over 2 years. METHODS: This randomized, double-blind, double-dummy, noninferiority study recruited 1395 women (aged 55-80 yrs; > or = 5 yrs since menopause) with osteoporosis [mean lumbar spine (L2-L4) BMD T-score < -2.5 and > or = -5.0]. Patients received IV ibandronate (2 mg every 2 mo or 3 mg every 3 mo) plus daily oral placebo, or 2.5 mg daily oral ibandronate plus 2- or 3-monthly IV placebo. Supplemental vitamin D (400 IU) and calcium (500 mg) were provided throughout the 2-year study. RESULTS: At 2 years, the 2- and 3-monthly IV regimens achieved statistically noninferior and also superior increases in lumbar spine BMD compared with the daily regimen (6.4% and 6.3% vs 4.8%, respectively; p < 0.001). Greater increases were also obtained with IV ibandronate versus daily in proximal femur BMD. Serum concentrations of the biochemical marker of bone resorption C-telopeptide of the alpha-chain of type I collagen were reduced to a similar extent in all treatment arms (53.4%-59.9%). The tolerability profile of the IV regimens was similar to that observed with daily oral therapy. CONCLUSION: Ibandronate IV injections are an effective and well tolerated treatment for postmenopausal osteoporosis and provide a useful alternative to oral dosing.     

Disorders associated with acute rapid and severe bone loss.

We describe a constellation of bone diseases characterized by the common feature of acute, rapid, and severe bone loss accompanied by dramatic fracture rates. These disorders are poorly recognized, resulting mainly from systemic diseases, frailty, immobilization, and immunosuppressive drugs, such as glucocorticoids and the calcineurin inhibitors. The opportunity to prevent or treat fractures is commonly missed because they are often not detected. Ideally, patients need to be identified early and preventative therapy initiated promptly to avoid the rapid bone loss and fractures. The most effective therapy at present seems to be the bisphosphonates, particularly when bone resorption is predominant. However, more severe forms of bone loss that result from an osteoblastic defect and reduced bone formation may benefit potentially more from newer anabolic agents, such as recombinant human parathyroid hormone (rhPTH).     

Management of Chronic Prostatitis (CP)

Purpose of Review

To review the most up-to-date diagnosis and treatment of chronic prostatitis. We conducted a review of the literature based on the diagnosis and treatment of chronic prostatitis.

Recent Findings

The use of advanced phenotyping, links to lifestyle, and multimodal approaches has helped to enhance the treatment of chronic prostatitis and its negative effects on quality of life.

Summary

Chronic prostatitis is a common and complex condition that requires a multimodal approach to treat symptoms. Recent advances in phenotyping and risk factors help to individualize treatment and enhance treatment outcomes.

     

Islet amyloid polypeptide: production by an osteoblast cell line and possible role as a paracrine regulator of osteoclast function in man.

1. The recently discovered peptide islet amyloid polypeptide shows considerable sequence homology with calcitonin-gene-related peptide, itself an alternative product of the calcitonin gene. The possibility that islet amyloid polypeptide might affect calcium homoeostasis and bone cell function was investigated. 2. Islet amyloid polypeptide messenger RNA was found to be expressed by human HTb 96 osteoblast-like cells in culture, and islet amyloid polypeptide immunoreactivity was present in the cell culture medium. 3. Infusion of islet amyloid polypeptide (150 pmol min-1 kg-1) caused a fall in serum calcium and phosphate concentrations in five patients with Paget's disease of the bone. This was similar to that caused by infusion of calcitonin (50 pmol min-1 kg-1). 4. These findings raise the possibility that islet amyloid polypeptide may act as a local factor within bone, produced by osteoblasts and regulating osteoclast function. The possibility of an action of islet amyloid polypeptide on the renal handling of calcium seems unlikely but is not totally excluded.