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Objective: The aim of the present study was to evaluate the utility of serum and pleural fluid biomarkers for predicting residual pleural scarring (RPS) in tuberculous pleuritis. Methodology: A retrospective study of patients with pleural tuberculosis was performed. Demographic data, clinical parameters, haematological indices, serum and pleural fluid biochemistry and pleural effusion area were assessed for correlation with the extent of RPS. Results: RPS was found in 41.4% of the 70 cases evaluated, with significant pleural scarring being present in 7.1%. It was more common in males (odds ratio 5.55). Among the variables studied, only the percentage reduction of the effusion after 2 weeks of treatment was found to independently predict the extent of RPS (r= -0.502, P< 0.001). Conclusion: RPS was more common in males and the percentage reduction in pleural effusion on CXR after 2 weeks of treatment was found to be a useful predictor of RPS. [ABSTRACT FROM AUTHOR]

Chitosan microparticles (CMPs) have previously been developed for topical applications to the eye, but their safety and efficacy in delivering proteins to the retina have not been adequately evaluated. This study examines the release kinetics of CMPs in vitro, and assesses their biocompatibility and cytotoxicity on retinal cells in vitro and in vivo. Two proteins were used in the encapsulation and release studies: BSA (bovine serum albumin) and tat-EGFP (enhanced green fluorescent protein fused to the transactivator of transcription peptide). Not surprisingly, the in vitro release kinetics were dependent on the protein encapsulated, with BSA showing higher release than tat-EGFP. CMPs containing encapsulated tat-EGFP were tested for cellular toxicity in photoreceptor-derived 661W cells. They showed no signs of in vitro cell toxicity at a low concentration (up to 1mgml(-1)), but at a higher concentration of 10mgml(-1) they were associated with cytotoxic effects. In vivo, CMPs injected into the subretinal space were found beneath the photoreceptor layer of the retina, and persisted for at least 8weeks. Similar to the in vitro studies, the lower concentration of CMPs was generally well tolerated, but the higher concentration resulted in cytotoxic effects and in reduced retinal function, as assessed by electroretinogram amplitudes. Overall, this study suggests that CMPs are effective long-term delivery agents to the retina, but the concentration of chitosan may affect cytotoxicity., (Copyright © 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

The efficient and controlled delivery of genes and proteins to retinal cells remains a challenge. In this study, we evaluated polyethylene glycol-polylactic acid (PEG-PLA) microparticles for encapsulation and delivery of a Transactivator of transcription-enhanced green fluorescent protein fusion (Tat-EGFP) to retinal cells. Our main objective was to develop a microparticle system that delivers Tat-EGFP with an initial rapid release (within 24 h) followed by a sustained release. We prepared four different formulations of Tat-EGFP encapsulated PEG-PLA particles to investigate the effects of protein and polymer concentrations on particle morphology and protein release, using scanning electron microscopy (SEM) and fluorometry techniques. The optimum formulation was selected based on higher protein release, and smaller particle size. The optimum formulation was then tested in vitro for cell biocompatibility and protein internalization, and in vivo for cellular toxicity following sub-retinal injections into rat eyes. The results suggest that PEG-PLA microparticles can deliver proteins in cell culture allowing protein internalization in as little as 1 h. In vivo, protein was shown to localize within the photoreceptor layer of the retina, and persist for at least 9 weeks with no observed toxicity., (Copyright 2010 Elsevier Ltd. All rights reserved.)

The inhibitors of apoptosis (IAP) proteins have emerged as important cancer targets. The cellular control of IAP expression is regulated by survival signaling pathways and by a variety of known intrinsic antagonists. Among these antagonists, the X-linked IAP-associated factor (XAF)1 is unique in its control of IAP function and in its ability to sensitize cancer cells to apoptosis. Studies have demonstrated that XAF1 is strongly pro-apoptotic, is inducible by IFN and is a tumor suppressor. Thus, this antagonist may have significant value in the treatment of cancer.

The inhibitor of apoptosis (IAP) genes constitute a highly conserved family found in organisms as diverse as insects and mammals. These genes encode proteins that directly bind and inhibit caspases, and thus play a critical role in deciding cell fate. The IAPs are in turn regulated by endogenous proteins (second mitochondrial activator of caspases and Omi) that are released from the mitochondria during apoptosis. Overexpression of the IAPs, particularly the X-chromosome-linked IAP, has been shown to be protective in a variety of experimental animal models of human neurodegenerative diseases. Furthermore, overexpression of one or more of the IAPs in cancer cell lines and primary tumor samples appears to be a frequent event. IAP gene amplification and translocation events provide genetic evidence that further strengthens the case for classifying the IAPs as oncogenes. Therapeutic strategies that interfere with IAP expression or function are under investigation as an adjuvant to conventional chemotherapy- and radiation-based cancer therapy. This paper reviews the structure and function of the IAP family members and their inhibitors, and surveys the available evidence for IAP dysregulation in cancer.

The inhibitors of apoptosis (IAPs) suppress apoptosis through the inhibition of the caspase cascade and thus are key proteins in the control of cell death. Here we have isolated the protein XIAP-associated factor 1 (XAF1) on the basis of its ability to bind XIAP, a member of the IAP family. XIAP suppresses caspase activation and cell death in vitro, and XAF1 antagonizes these XIAP activities. Expression of XAF1 triggers a redistribution of XIAP from the cytosol to the nucleus. XAF1 is ubiquitously expressed in normal tissues, but is present at low or undetectable levels in many different cancer cell lines. Loss of control over apoptotic signalling is now recognized as a critical event in the development of cancer. Our results indicate that XAF1 may be important in mediating the apoptosis resistance of cancer cells.

X-linked inhibitor of apoptosis protein (XIAP) is a potent modulator of programmed cell death. XIAP specifically binds and inhibits the function of caspase-3, -7, and -9, key effector proteases of apoptosis. We recently isolated, by yeast two-hybrid screening, a novel 34-kDa zinc finger protein, XIAP-associated factor 1 (XAF1). Both the caspase inhibiting and the anti-apoptotic abilities of XIAP were found to be blocked by overexpressed XAF1. Here, we report the isolation and characterization of the human XAF1 gene. The xaf1 gene consists of seven exons spanning 18 kb. Fluorescence in situ hybridization analysis localized the xaf1 locus at 17p13.2, telomeric to the p53 gene. The xaf1 locus was further refined to YAC 746C10, approximately 3 cM distal to TP53. Microsatellite analysis of the xaf1 locus using the NCI 60 cell line panel revealed significantly decreased heterozygosity at all three polymorphic markers tested, suggesting that allelic loss of the xaf1 gene is prevalent in cancer cell lines. Examination of the same NCI cell line panel for xaf1 RNA expression demonstrated that cancer cell lines exhibited very low levels of mRNA relative to normal human liver. In contrast, XIAP mRNA levels were relatively high in the majority of cancer cell lines tested. We propose that a high level of XIAP to XAF1 expression in cancer cells may provide a survival advantage through the relative increase of XIAP anti-apoptotic function., (Copyright 2000 Academic Press.)

Transient forebrain ischemia produced by four-vessel occlusion (4-VO) triggers the delayed death of CA1 neurons in the hippocampus, resulting in behavioral deficits of spatial learning performance. We demonstrate that CA1 neuronal loss induced by 4-VO (12 min) is preceded by a selective and marked elevation of catalytically active caspase-3 in these neurons, indicative of apoptosis. Virally mediated overexpression of the anti-apoptotic gene X chromosome-linked inhibitor of apoptosis protein (XIAP) prevented both the production of catalytically active caspase-3 and degeneration of CA1 neurons after transient forebrain ischemia. CA1 neurons protected in this manner appeared to function normally, as assessed by immunohistochemical detection of the neuronal activity marker nerve growth factor inducible-A and by spatial learning performance in the Morris water maze. These findings indicate that caspase-3 activation is a key event in ischemic neuronal death and that blockade of this event by XIAP overexpression permits CA1 neurons to survive and operate properly after an ischemic insult.

Genomic and cDNA clones encoding mouse inhibitor of apoptosis protein 1 and 2 (Miap1 and Miap2) were isolated and characterized. The genes encoding the 602-amino-acid MIAP1 protein and the 612-amino-acid MIAP2 protein are contained within a 57-kb locus in a tandem head-to-tail arrangement. The Miap1 gene consists of nine exons spanning 24 kb, and the Miap2 gene consists of seven exons spanning 21 kb. Fluorescence in situ hybridization analysis mapped the locus to chromosome 9A2, which is syntenic with portions of the human 11q22-q23 region containing the human homologues HIAP1 and HIAP2. Sequencing of the complete Miap1 and Miap2 cDNAs revealed an unusually long 5' untranslated region in the Miap2 transcript, which may indicate nonscanning ribosomal initiation of translation.

IAPs (inhibitor of apoptosis proteins) are a recently identified family of proteins that function in the cell death pathway to inhibit programmed cell death. We have earlier reported cloning of four human IAPs: NAIP, hiap-1, hiap-2, and xiap. To facilitate studies of these genes, we have undertaken the cloning of their murine homologues. We report here the cloning, mapping, and preliminary characterization (including cellular and tissue distribution profile) of the murine homologue of the human X-linked IAP (xiap). The mouse gene called miap-3 (for murine IAP-3; GenBank Accession No. nuc 1 U88990) has a coding region of 1.5 kb that encodes a protein of 55 kDa and has 87 and 94% homology with its human homologue at DNA and amino acid levels, respectively. Northern blot analysis reveals an 8-kb miap-3 transcript in all tissues examined to date. miap-3 is composed of six exons and five introns spanning approximately 20 kb. miap-3 has been assigned to the A3-A5 region of mouse chromosome X by FISH analysis.

Bone marrow is the major site of hematopoiesis in the adult mammal. Bone marrow contains a highly organized microenvironment for the support of hematopoietic stem and progenitor cells, including the production of growth factors. Bone marrow cells also produce negative regulatory factors which may regulate hematopoiesis and inflammatory responses. In this paper we describe Reptimed, a unique bone marrow-derived factor with inhibitory activity for myelopoiesis and in vitro growth of myeloid cell lines. Reptimed was partially purified from bone marrow supernatants using a combination of solid-phase extraction and size exclusion chromatography. Reptimed is < 1000 Da MW and is water soluble. Reptimed inhibited growth of granulocyte-macrophage and macrophage colonies as well as proliferation of several myeloid leukemia cell lines. Reptimed may be part of a hemoregulatory circuit.

A reverse phase high pressure liquid chromatographic method is presented for the separation and determination of residues of the carbamates oxamyl and methomyl on vegetables. A liquid-liquid extraction and cleanup procedure is applied to the vegetable extract. Samples are eluted from a muBondapak C18 column and quantitated by ultraviolet absorbance at 240 nm. Recovery data for vegetable samples spiked at 2 ppm are presented.