Lead cytotoxicity in primary cultured rat astrocytes and Schwann cells

In human neutrophils (PMN) the ethanolamine-containing phosphoglyceride fraction (PE), principally plasmalogen-linked PE (1-O-alk-1'-enyl-2-acyl-sn-glycero-3-phosphoethanolamine), is the major store of arachidonic acid (AA). Exogenous AA is initially incorporated into 1-acyl-linked phosphoglycerides and is believed to be transferred into the 1-ether-linked phosphoglycerides via the action of a CoA-independent transacylase (CoA-IT). We have investigated the selectivity for both the "acceptor' lysophospholipids and "donor' AA-containing phospholipid substrates in the CoA-IT reaction. Evidence suggests CoA-IT may also participate in the synthesis of platelet activating factor. The transfer of [3H]AA from endogenously labeled choline-containing phosphoglycerides (PC) to exogenously added alkenyl-lyso-PE (0-50 microM) was examined in saponin-permeabilized PMN. In these "donor' studies, we observed that [3H]AA was transferred from both alkyl- and diacyl-linked PC in a proportional manner. More detailed molecular species analysis showed that [3H]AA was deacylated from all the major AA-containing molecular species in both the alkyl and diacyl subclasses with no selectivity for either subclass. To investigate the "acceptor' selectivity, membrane fractions prelabeled with either [3H]alkyl-arachidonoyl-PE or -PC were utilized as donor substrates. Various unlabeled lysophospholipids (10 microM) were added and the generation of [3H]lyso-PE or -PC was monitored as a measure of CoA-IT activity. Significant subclass preference was observed upon addition of lyso-PE species (1-alkenyl > 1-alkyl > 1-acyl) however, little selectivity was seen with the corresponding lyso-PC species. On the other hand, lysophosphatidylserine, lysophosphatidylinositol, and lysophosphatidic acid all served as poor acceptor substrates in the reaction. These data from PMN are consistent with other evidence that the CoA-IT plays a pivotal role in the enrichment of AA into plasmalogen-linked PE.     

Clinical study on treatment of chemo- or radiotherapy induced leukopenia with fuzheng compound

The therapeutic effect of Fuzhen Compound, a Chinese herbal medicine, on leukocyte count in 59 patients with cancer of advanced stage after chemo-or radiotherapy were observed. Among 41 cases with leukopenia before treatment, leukocyte of 37 cases were normalized after treatment, the count pre-and post-treatment were (2.8 +/- 0.6) x 10(9)/L and (5.9 +/- 1.4) x 10(9)/L respectively (P < 0.01). In 18 patients with normal leukocyte count before treatment, the counts of 17 cases were still kept in normal after treatment. The time for leukcoyte recovering was 8.0 days in average, while that of 23 patients did not take Fuzhen Compound was 20.6 +/- 1.8 days. The results indicated that the Fuzhen Compound could alleviate the inhibition of chemo-or radiotherapy on hemopoietic function of bone marrow and has leukocytogenic effect.     

Peptide containing the BCR oligomerization domain (AA 1-160) reverses the transformed phenotype of p210bcr-abl positive 32D myeloid leukemia cells

BACKGROUND: The aim of this study was to evaluate the efficacy of 1.5 mg/kg bolus of amrinone on low cardiac output (CO) state following emergence from cardiopulmonary bypass (CPB) in cardiac surgical patients. METHODS: Immediately after emergency from CPB, 14 patients with a cardiac index (CI) less than 2.2 l.min-1.m-2 despite administration of inotropes and nitroglycerin, received 1.5 mg/kg amrinone over 3 min without changing catecholamine infusion rates (amrinone group). Hemodynamics and left ventricular short axis views with transesophageal echocardiography were recorded at baseline, 3, 4, and 10 min following amrinone administration. Left ventricular filling volumes were maintained constant by volume reinfusion from the CPB reservoir. We matched the data of the amrinone group with the other 14 patients who did not receive amrinone (non-amrinone group) to evaluate the efficacy of amrinone in low CO state. RESULTS: At baseline, CI (1.8 +/- 0.1 l.min-1.m-2) in the amrinone group was significantly lower than CI (3.0 +/- 0.2) in the non-amrinone group. Following amrinone administration, CI and velocity of circumferential fibershortening corrected for heart rate (Vcfc) significantly increased, and systemic vascular resistance index and pulmonary vascular resistance index significantly decreased from the baseline within 10 min without changes in heart rate, mean arterial blood pressure, or pulmonary artery occlusion pressure, and became equivalent with those of the non-amrinone group. CONCLUSIONS: A 1.5 mg/kg amrinone loading dose to patients in a low CO state, despite catecholamine therapy immediately after emergence from CPB, effectively improves ventricular function when loading conditions are maintained constant.     

Matching antibody class with pathogen type and portal of entry: cognate mechanisms regulate local isotype expression patterns in lymph nodes draining the respiratory tract of mice inoculated with respiratory viruses, according to virus replication competence and site of inoculation

Intranasal deposition of Sendai virus (SV) in C57BL/6 mice provokes an Ab-forming cell (AFC) reaction in mediastinal (MLN) and cervical lymph nodes (CLN), which drain the lungs and upper respiratory tract, respectively. While the majority of AFC elicited by infectious SV at both sites produced IgG, the CLN response to SV rendered inactive in replication was restricted almost entirely to IgA, although isotype switching in mediastinal continued to be skewed heavily to IgG. However, in vitro restimulation of the accompanying virus-specific T cell populations from the two sites did not reveal any significant difference in lymphokine output, and isotype expression was not altered substantially in mice lacking IL-4 or IL-6 genes. To dissociate the response to specific Ags from the inflammatory reaction to viral infection, we examined the response to inactivated SV in the face of infection with influenza virus A/HKx31. The magnitude and IgA dominance of the anti-SV AFC population in the CLN were unaffected by a simultaneous, vigorous, IgG-dominated CLN anti-influenza reaction. Evidently, the characteristics of this antiviral response are determined primarily by cognate interactions. Moreover, the IgA bias of the CLN AFC response to inactivated SV was observed only when the virus was delivered intranasally: injection under the epidermis of the cheek, a site that has a lymphatic drainage into the CLN, resulted in an IgG-dominated CLN AFC reaction, lacking IgA. The site of deposition of a vaccine can thus have more influence on the pattern of isotypes induced than the site at which the immune response is initiated.     

2005～2007年度BIPM放射性剂量比对与刻度情况简介

本文系统的介绍了国际计量局(BIPM)2005～2007年度组织世界各国初级标准实验室放射性剂量的比对和刻度情况,以及BIPM到2009年的放射性剂量的比对和刻度计划.     

Prefabrication of bilaminar-epithelialized composite flap with tissue expander and cultured keratinocytes

This study investigated the feasibility of prefabrication of a bilaminar-epithelialized flap by using a tissue expander and cultured keratinocytes, for reconstruction of perforate defects in the oral cavity and upper aerodigestive tract. In each of six rats, a 10-ml volume expander was implanted under the inferior epigastric flap and a thin silicon catheter was introduced into periexpander space. Seven days after implantation, 10 x 10(6) cultured keratinocytes, isolated from inbred donor rats, were suspended in fibrin glue and injected into the periexpander space through the catheter (n = 4 of 6). The expansion was started immediately after cell inoculation and lasted at least 3 weeks at the speed of 2 to 3 ml every 5 to 7 days. At the end of expansion, the periexpander space was opened and the capsule around the tissue expander was found to be covered completely with a neoepithelium. Thus, a bilaminar-epithelialized flap based on femoral vessels was elevated and successfully transferred to cover the excisional perforate defect in the oral cavity with the neoepithelial side as inner lining. All flaps treated with 10 x 10(6) cultured keratinocytes survived with complete wound healing during a 1-week follow-up (n = 4 of 6). Both macroscopic and histologic findings demonstrated that a bilaminar-epithelialized composite flap can be fabricated by using a tissue expander and keratinocyte-fibrin glue suspension.     

Distinct actions of interleukin-9 and interleukin-4 on a hematopoietic stem cell line, EMLC1

EMLC1 is a hematopoietic stem cell line that depends on stem cell factor (SCF) for growth and generates lymphoid, erythroid and myeloid progenitors in the presence of different cytokines. We have studied signaling events leading to cell proliferation and differentiation of EMLC1 mediated by interleukin (IL)-4 and IL-9. It was found that IL-9 enhances SCF-induced cell proliferation and promotes erythropoietin (EPO)-dependent erythroid differentiation of EMLC1 cells. However, IL-9 alone cannot support the growth of this cell line. In contrast, IL-4 by itself is sufficient to promote the growth of EMLC1 cells, even in the absence of SCF. Antiphosphotyrosine immunoblots of total cell lysates demonstrated that IL-4 and IL-9 induce tyrosine phosphorylation of different cellular substrates. Both IL-4 and IL-9 stimulated tyrosine phosphorylation of SHP-2, whereas the 90-kD tyrosine phosphorylated protein induced by IL-9 stimulation is Stat3. We have also shown that IL-4 is much more potent than IL-9 in inducing the expression of primary response gene c-myc. It was further determined that c-myc antisense oligodeoxynucleotide blocked IL-4 supported cell growth. Taken together, these results indicate that IL-4 may serve as a growth-promoting factor for hematopoietic stem cells, and IL-9 enhances both growth and erythroid differentiation of primitive hematopoietic progenitors. The results also suggest that differences in tyrosine phosphorylation induced by IL-4 and IL-9 may in part determine their distinct biological functions.     

A bayesian approach to Arrhenius prediction of shelf-life

The use of a bayesian method for estimating the shelf-life of pharmaceutical formulations is evaluated and compared with classical linear regression. Using three real data sets, the greater flexibility provided by the bayesian approach is demonstrated. In particular, the bayesian approach enabled the consideration of cases when the error distribution is non-normal. However much more computation is required with the bayesian method.     

A polymerase chain reaction assay for detecting snails infected with bilharzia parasites (Schistosoma mansoni) from very early prepatency

In the present study, we adapted a polymerase chain reaction (PCR) assay, previously shown by us to be very sensitive for detecting cercariae in water, for the sensitive detection of Schistosoma mansoni DNA in infected snails from early prepatency. Polymerase chain reaction primers were designed based on the 121-basepair highly repeated sequence we previously identified in the genome of S. mansoni. The DNA was prepared from the snails by a simple alkaline extraction procedure, and the PCR assay enabled a clear differentiation between infected and normal snails. Infected snails were detected as early as one day after penetration of a single miracidium. The high sensitivity of the test enabled identification of a single infected snail even when its DNA was pooled with material from up to 99 uninfected snails, thus demonstrating the possibility of mass diagnosis in pools of snails. The assay has the potential for large-scale determination of prepatent infection prevalence in snails, thus offering new possibilities for the evaluation of schistosomiasis transmission and for schistosomiasis control, as discussed.     

Neonatal capsaicin treatment abolishes formalin-induced spinal PGE2 release

We investigated the effect of neonatal capsaicin treatment on formalin-evoked pain behavior and spinal levels of nociceptive neuromodulators using in vivo intrathecal microdialysis in conscious adult rats and age-matched controls. Capsaicin-treated rats displayed thermal hypoalgesia and a significant decrease in tissue content of calcitonin gene-related peptide. Paw swelling, flinching and release of spinal prostaglandin E2 induced by injection of formalin into the hindpaw were also reduced in capsaicin-treated rats compared with controls, whereas glutamate, aspartate and taurine release was unaffected. These data suggest that formalin-induced inflammation, pain behavior and spinal prostaglandin E2 release are mediated by mechanisms sensitive to neonatal capsaicin while the formalin-evoked release of amino acids in the spinal cord is not.