A Quantitative Method to Analyze Drosophila Pupal Eye Patterning

BACKGROUND:The Drosophila pupal eye has become a popular paradigm for understanding morphogenesis and tissue patterning. Correct rearrangement of cells between ommatidia is required to organize the ommatidial array across the eye field. This requires cell movement, cell death, changes to cell-cell adhesion, signaling and fate specification. METHODOLOGY:We describe a method to quantitatively assess mis-patterning of the Drosophila pupal eye and objectively calculate a 'mis-patterning score' characteristic of a specific genotype. This entails step-by-step scoring of specific traits observed in pupal eyes dissected 40-42 hours after puparium formation and subsequent statistical analysis of this data. SIGNIFICANCE:This method provides an unbiased quantitative score of mis-patterning severity that can be used to compare the impact of different genetic mutations on tissue patterning

The Effects of Sleep Hypoxia on Coagulant Factors and Hepatic Inflammation in Emphysematous Rats

OBJECTIVES: To develop a sleep hypoxia (SH) in emphysema (SHE) rat model and to explore whether SHE results in more severe hepatic inflammation than emphysema alone and whether the inflammation changes levels of coagulant/anticoagulant factors synthesized in the liver. METHODS: Seventy-five rats were put into 5 groups: SH control (SHCtrl), treated with sham smoke exposure (16 weeks) and SH exposure (12.5% O(2), 3 h/d, latter 8 weeks); emphysema control (ECtrl), smoke exposure and sham SH exposure (21% O(2)); short SHE (SHEShort), smoke exposure and short SH exposure (1.5 h/d); mild SHE (SHEMild), smoke exposure and mild SH exposure (15% O(2)); standard SHE (SHEStand), smoke exposure and SH exposure. Therefore, ECtrl, SHEShort, SHEMild and SHEStand group were among emphysematous groups. Arterial blood gas (ABG) data was obtained during preliminary tests. After exposure, hepatic inflammation (interleukin -6 [IL-6] mRNA and protein, tumor necrosis factor α [TNFα] mRNA and protein) and liver coagulant/anticoagulant factors (antithrombin [AT], fibrinogen [FIB] and Factor VIII [F VIII]) were evaluated. SPSS 11.5 software was used for statistical analysis. RESULTS: Characteristics of emphysema were obvious in emphysematous groups and ABGs reached SH criteria on hypoxia exposure. Hepatic inflammation parameters and coagulant factors are the lowest in SHCtrl and the highest in SHEStand while AT is the highest in SHCtrl and the lowest in SHEStand. Inflammatory cytokines of liver correlate well with coagulant factors positively and with AT negatively. CONCLUSIONS: When SH is combined with emphysema, hepatic inflammation and coagulability enhance each other synergistically and produce a more significant liver-derivative inflammatory and prothrombotic status

The timing of ostomy closure in infants with necrotizing enterocolitis: a systematic review

Item does not contain fulltextPURPOSE: The optimal timing of ostomy closure is a matter of debate. We performed a systematic review of outcomes of early ostomy closure (EC, within 8 weeks) and late ostomy closure (LC, after 8 weeks) in infants with necrotizing enterocolitis. METHODS: PubMed, EMbase, Web-of-Science, and Cinahl were searched for studies that detailed time to ostomy closure, and time to full enteral nutrition (FEN) or complications after ostomy closure. Patients with Hirschsprung's disease or anorectal malformations were excluded. Analysis was performed using SPSS 17 and RevMan 5. RESULTS: Of 778 retrieved articles, 5 met the inclusion criteria. The median score for study quality was 9 [range 8-14 on a scale of 0 to 32 points (Downs and Black, J Epidemiol Community Health 52:377-384, 1998)]. One study described mean time to FEN: 19.1 days after EC (n = 13) versus 7.2 days after LC (n = 24; P = 0.027). Four studies reported complication rates after ostomy closure, complications occurred in 27% of the EC group versus 23% of the LC group. The combined odds ratio (LC vs. EC) was 1.1 [95% CI 0.5, 2.5]. CONCLUSION: Evidence that supports early or late closure is scarce and the published articles are of poor quality. There is no significant difference between EC versus LC in the complication rate. This systematic review supports neither early nor late ostomy closure

Household out-of-pocket payments for illness: Evidence from Vietnam

BACKGROUND: In Vietnam, illnesses create high out-of-pocket health care expenditures for households. In this study, the burden of illness in the Bavi district, Vietnam is measured based upon individual household health expenditures for communicable and non-communicable illnesses. The focus of the paper is on the relative effect of different illnesses on the total economic burden of health care on households in general and on households that have catastrophic health care spending in particular. METHODS: The study was performed by twelve monthly follow-up interviews of 621 randomly selected households. The households are part of the FilaBavi project sample – Health System Research Project. The heads of household were interviewed at monthly intervals from July 2001 to June 2002. RESULTS: For the population in the Bavi district, communicable illnesses predominate among the episodes of illness and are the reason for most household health care expenditure. This is the case for almost all groups within the study and for the study population as a whole. However, communicable illnesses are more dominant in the poor population compared to the rich population, and are more dominant in households that have very large, or catastrophic, health care expenditure, compared to those without such expenditures. CONCLUSION: The main findings indicate that catastrophic health care spending for a household is not usually the result of one single disastrous event, but rather a series of events and is related more to "every-day illnesses" in a developing country context than to more spectacular events such as injuries or heart illnesses

An EMT-Driven Alternative Splicing Program Occurs in Human Breast Cancer and Modulates Cellular Phenotype

Epithelial-mesenchymal transition (EMT), a mechanism important for embryonic development, plays a critical role during malignant transformation. While much is known about transcriptional regulation of EMT, alternative splicing of several genes has also been correlated with EMT progression, but the extent of splicing changes and their contributions to the morphological conversion accompanying EMT have not been investigated comprehensively. Using an established cell culture model and RNA–Seq analyses, we determined an alternative splicing signature for EMT. Genes encoding key drivers of EMT–dependent changes in cell phenotype, such as actin cytoskeleton remodeling, regulation of cell–cell junction formation, and regulation of cell migration, were enriched among EMT–associated alternatively splicing events. Our analysis suggested that most EMT–associated alternative splicing events are regulated by one or more members of the RBFOX, MBNL, CELF, hnRNP, or ESRP classes of splicing factors. The EMT alternative splicing signature was confirmed in human breast cancer cell lines, which could be classified into basal and luminal subtypes based exclusively on their EMT–associated splicing pattern. Expression of EMT–associated alternative mRNA transcripts was also observed in primary breast cancer samples, indicating that EMT–dependent splicing changes occur commonly in human tumors. The functional significance of EMT–associated alternative splicing was tested by expression of the epithelial-specific splicing factor ESRP1 or by depletion of RBFOX2 in mesenchymal cells, both of which elicited significant changes in cell morphology and motility towards an epithelial phenotype, suggesting that splicing regulation alone can drive critical aspects of EMT–associated phenotypic changes. The molecular description obtained here may aid in the development of new diagnostic and prognostic markers for analysis of breast cancer progression.National Institutes of Health (U.S.) (R01-HG002439)National Science Foundation (U.S.) (equipment grant)National Institutes of Health (U.S.) (Integrative Cancer Biology Program Grant U54-CA112967)David H. Koch Institute for Integrative Cancer Research at MIT (Ludwig Center for Metastasis Research)David H. Koch Institute for Integrative Cancer Research at MITMassachusetts Institute of Technology (Croucher Scholarship)Massachusetts Institute of Technology (Ludwig Fund postdoctoral fellowship)National Institutes of Health (U.S.) (NIH CA100324)National Institutes of Health (U.S.) (AECC9526-5267

Cell Proliferation in the Presence of Telomerase

BACKGROUND: Telomerase, which is active early in development and later in stem and germline cells, is also active in the majority of human cancers. One of the known functions of telomerase is to extend the ends of linear chromosomes, countering their gradual shortening at each cell division due to the end replication problem and postreplication processing. Telomerase concentration levels vary between different cell types as well as between different tumors. In addition variable telomerase concentrations will exist in different cells in the same tumor when telomerase inhibitors are used, because of limitations of drug delivery in tissue. Telomerase extends short telomeres more frequently than long telomeres and the relation between the extension frequency and the telomere length is nonlinear. METHODOLOGY/PRINCIPAL FINDINGS: Here, the biological data of the nonlinear telomerase-telomere dynamics is incorporated in a mathematical theory to relate the proliferative potential of a cell to the telomerase concentration in that cell. The main result of the paper is that the proliferative capacity of a cell grows exponentially with the telomerase concentration. CONCLUSIONS/SIGNIFICANCE: The theory presented here suggests that long term telomerase inhibition in every cancer progenitor or cancer stem cell is needed for successful telomere targeted cancer treatment. This theory also can be used to plan and assess the results of clinical trials targeting telomerase

A Functional Misexpression Screen Uncovers a Role for Enabled in Progressive Neurodegeneration

Drosophila is a well-established model to study the molecular basis of neurodegenerative diseases. We carried out a misexpression screen to identify genes involved in neurodegeneration examining locomotor behavior in young and aged flies. We hypothesized that a progressive loss of rhythmic activity could reveal novel genes involved in neurodegenerative mechanisms. One of the interesting candidates showing progressive arrhythmicity has reduced enabled (ena) levels. ena down-regulation gave rise to progressive vacuolization in specific regions of the adult brain. Abnormal staining of pre-synaptic markers such as cystein string protein (CSP) suggest that axonal transport could underlie the neurodegeneration observed in the mutant. Reduced ena levels correlated with increased apoptosis, which could be rescued in the presence of p35, a general Caspase inhibitor. Thus, this mutant recapitulates two important features of human neurodegenerative diseases, i.e., vulnerability of certain neuronal populations and progressive degeneration, offering a unique scenario in which to unravel the specific mechanisms in an easily tractable organism