565 research outputs found

    Why Do Athletes Use Eye Black?

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    Ransomware is Quietly Devastating American Healthcare Facilities

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    The patient didn’t attract any attention initially. They were just one more cog moving through the system that was the massive hospital complex on your average day. That was, until they were shown to a room, and left alone. At that point, they removed a flash drive from their pocket and tried to insert it into a computer — with the goal of accessing the hospitals computer systems. This is according to the Chief Information Security Officer at a major Northwest university hospital system, who asked for anonymity due to the sensitive nature of such attacks. The imposter patient was attempting to install malware on the hospitals system, potentially with devastating effects. And although security was alerted to their presence, the imposter was able to sneak out, and was not caught. This happens more often than you might think. In fact, it also happens with people impersonating residents. “Every July we have brand new physicians as residents coming in, and even though we have pictures of everybody, it’s easy to slip in,” says the officer. Ransomware attacks, in which malware denies the victim (such as a hospital) access to a computer system or data until a ransom is paid, have exponentially increased across the U.S. in the last few years. They’ve resulted in ambulances having to be diverted to get care for the patients they carry, chief medical officers being unable to administer important medications because they’re locked out of patient medical records, and even some smaller medical practices having to shut down entirely after their patient and billing records were deleted for refusing to pay the ransom. In conversations with over a dozen experts, hospital representatives, government authorities and others, they contend the pace of ransomware attacks on US healthcare facilities such as hospitals is only set to increase. The costs of dealing with such attacks, the life-threatening impacts it can have on patients, and the technical expertise of repelling them are a never-ending game of cat and mouse, in which security practitioners and IT officers are perpetually trying to defend against new threats. Whether they’ll succeed is still an open question. Link: https://medium.com/p/3829e94bf4c5

    Internally heated and fully compressible convection: flow morphology and scaling laws

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    In stars and planets natural processes heat convective flows in the bulk of a convective region rather than at hard boundaries. By characterizing how convective dynamics are determined by the strength of an internal heating source we can gain insight into the processes driving astrophysical convection. Internally heated convection has been studied extensively in incompressible fluids, but the effects of stratification and compressibility have not been examined in detail. In this work, we study fully compressible convection driven by a spatially uniform heating source in 2D and 3D Cartesian, hydrodynamic simulations. We use a fixed temperature upper boundary condition which results in a system that is internally heated in the bulk and cooled at the top. We find that the flow speed, as measured by the Mach number, and turbulence, as measured by the Reynolds number, can be independently controlled by separately varying the characteristic temperature gradient from internal heating and the diffusivities. 2D simulations at a fixed Mach number (flow speed) demonstrate consistent power at low wavenumber as diffusivities are decreased. We observe convection where the velocity distribution is skewed towards cold, fast downflows, and that the flow speed is related to the length scale and entropy gradient of the upper boundary where the downflows are driven. We additionally find a heat transport scaling law which is consistent with prior incompressible work.Comment: 22 pages, 12 figures, submitted to Phys. Rev. Fluid

    High-Risk Microgranular Acute Promyelocytic Leukemia with a Five-Way Complex Translocation Involving PML-RARA

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    Acute promyelocytic leukemia (APL) is classically characterized by chromosomal translocation (15;17), resulting in the PML-RARA fusion protein leading to disease. Here, we present a case of a 50-year-old man who presented with signs and symptoms of acute leukemia with concern for APL. Therapy was immediately initiated with all-trans retinoic acid. The morphology of his leukemic blasts was consistent with the hypogranular variant of APL. Subsequent FISH and cytogenetic analysis revealed a unique translocation involving five chromosomal regions: 9q34, 17q21, 15q24, 12q13, and 15q26.1. Molecular testing demonstrated PML/RARA fusion transcripts. Treatment with conventional chemotherapy was added and he went into a complete remission. Given his elevated white blood cell count at presentation, intrathecal chemotherapy for central nervous system prophylaxis was also given. The patient remains on maintenance therapy and remains in remission. This is the first such report of a 5-way chromosomal translocation leading to APL. Similar to APL with chromosomal translocations other than classical t(15;17) which result in the typical PML-RARA fusion, our patient responded promptly to an ATRA-containing regimen and remains in complete remission

    Fertility Intentions and Clinical Care Attendance Among Women Living with HIV in South Africa

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    Poor HIV care retention impedes optimal treatment outcomes in persons living with HIV. Women trying to become pregnant may be motivated by periconception horizontal and vertical transmission concerns and thus more likely to attend HIV care visits than women not trying to conceive. We estimated the effect of fertility intentions on HIV care attendance over 12 months among non-pregnant, HIV-positive women aged 18–35 years who were on or initiating antiretroviral therapy in Johannesburg, South Africa. The percentage of women attending an HIV care visit decreased from 93.4% in the first quarter to 82.8% in the fourth quarter. Fertility intentions were not strongly associated with care attendance in this cohort of reproductive-aged women; however, attendance declined over time irrespective of childbearing plans. These findings suggest a need for reinforced efforts to support care engagement and risk reduction, including safer conception practices for women wishing to conceive

    Longitudinal patterns of unmet need for contraception among women living with HIV on antiretroviral therapy in South Africa

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    Objectives: Fertility intentions and contraceptive use are often not assessed in the context of clinical HIV care, representing a possible programming gap if women's family planning needs change over time. We aimed to identify longitudinal patterns of unmet need for contraception over a 12-month period among women living with HIV taking antiretroviral therapy (ART). Study design: 850 non-pregnant, HIV-positive women aged 18-35 on or initiating ART in Johannesburg, South Africa, were enrolled into a prospective cohort study in 2009-2010. Fertility intentions and contraceptive use were assessed during routine HIV care visits via an interviewer-administered questionnaire, and women were referred for on-site contraceptive counseling. We used group-based trajectory modeling to identify patterns of unmet need for contraception over 12 months, first in the entire population and then in a subset of recent ART initiators. Results: In the full population we identified four patterns of unmet need for contraception over one year. Half of the enrolled women were predicted to have a consistently high probability of unmet need, 22.9% a consistently low probability, 16.7% a decreasing probability, and 10.4% an increasing probability over time. Contraceptive method discontinuation and rapidly changing fertility intentions were the primary drivers of changing (increasing or decreasing) unmet need over follow-up. Results were similar in recent ART initiators. Conclusions: Half of women were estimated to have a high probability of unmet need that persisted over time, and more than a quarter were estimated to experience patterns of changing unmet need over 12 months. Family planning needs should be assessed more regularly in HIV-positive women to prevent unintended pregnancies and support safer conception among women trying to conceive

    HLAProfiler utilizes k-mer profiles to improve HLA calling accuracy for rare and common alleles in RNA-seq data

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    BACKGROUND: The human leukocyte antigen (HLA) system is a genomic region involved in regulating the human immune system by encoding cell membrane major histocompatibility complex (MHC) proteins that are responsible for self-recognition. Understanding the variation in this region provides important insights into autoimmune disorders, disease susceptibility, oncological immunotherapy, regenerative medicine, transplant rejection, and toxicogenomics. Traditional approaches to HLA typing are low throughput, target only a few genes, are labor intensive and costly, or require specialized protocols. RNA sequencing promises a relatively inexpensive, high-throughput solution for HLA calling across all genes, with the bonus of complete transcriptome information and widespread availability of historical data. Existing tools have been limited in their ability to accurately and comprehensively call HLA genes from RNA-seq data. RESULTS: We created HLAProfiler ( https://github.com/ExpressionAnalysis/HLAProfiler ), a k-mer profile-based method for HLA calling in RNA-seq data which can identify rare and common HLA alleles with > 99% accuracy at two-field precision in both biological and simulated data. For 68% of novel alleles not present in the reference database, HLAProfiler can correctly identify the two-field precision or exact coding sequence, a significant advance over existing algorithms. CONCLUSIONS: HLAProfiler allows for accurate HLA calls in RNA-seq data, reliably expanding the utility of these data in HLA-related research and enabling advances across a broad range of disciplines. Additionally, by using the observed data to identify potential novel alleles and update partial alleles, HLAProfiler will facilitate further improvements to the existing database of reference HLA alleles. HLAProfiler is available at https://expressionanalysis.github.io/HLAProfiler/

    Trajectories of fertility intentions among women living with HIV in South Africa

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    Fertility intentions are thought to be dynamic among women of reproductive age, yet few studies have assessed fertility intentions over time among women with HIV. We examine temporal patterns of fertility intentions in women with HIV to assess the extent to which fertility intentions–and the corresponding need for safer conception and judicious antiretroviral therapy (ART) regimen selection–vary over time. 850 non-pregnant HIV-positive women aged 18–35 on or being initiated onto ART in Johannesburg, South Africa were enrolled into a prospective cohort study (2009–2010). Fertility intentions were assessed at enrollment and at 30-day intervals via an interviewer-administered questionnaire. We used group-based trajectory modelling to identify longitudinal patterns of fertility intentions over 12 months. We identified four patterns of fertility intentions, which we labelled “consistently low” (representing ∼60% of the population), “low and increasing” (∼23%), “high and increasing” (∼12%), and “high and decreasing” (∼5%). Our findings suggest that a single family-planning assessment at one time point is insufficient to fully identify and meet the reproductive needs of women with HIV. As HIV testing and treatment evolve in South Africa, routine screening for fertility intentions can offer important opportunities to optimize HIV treatment, prevention, and maternal and child health

    Incident HIV among pregnant and breast-feeding women in sub-Saharan Africa: a systematic review and meta-analysis

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    OBJECTIVES: A previous meta-analysis reported high HIV incidence among pregnant and breast-feeding women in sub-Saharan Africa (SSA), but limited evidence of elevated risk of HIV acquisition during pregnancy or breast-feeding when compared with nonpregnant periods. The rapidly evolving HIV prevention and treatment landscape since publication of this review may have important implications for maternal HIV incidence. DESIGN: Systematic review and meta-analysis. METHODS: We searched four databases and abstracts from relevant conferences through 1 December 2018, for literature on maternal HIV incidence in SSA. We used random-effects meta-analysis to summarize incidence rates and ratios, and to estimate 95% prediction intervals. We evaluated potential sources of heterogeneity with random-effects meta-regression. RESULTS: Thirty-seven publications contributed 100 758 person-years of follow-up. The estimated average HIV incidence rate among pregnant and breast-feeding women was 3.6 per 100 person-years (95% prediction interval: 1.2--11.1), while the estimated average associations between pregnancy and risk of HIV acquisition, and breast-feeding and risk of HIV acquisition, were close to the null. Wide 95% prediction intervals around summary estimates highlighted the variability of HIV incidence across populations of pregnant and breast-feeding women in SSA. Average HIV incidence appeared associated with age, partner HIV status, and calendar time. Average incidence was highest among studies conducted pre-2010 (4.1/100 person-years, 95% prediction interval: 1.1--12.2) and lowest among studies conducted post-2014 (2.1/100 person-years, 95% prediction interval: 0.7--6.5). CONCLUSION: Substantial HIV incidence among pregnant and breast-feeding women in SSA, even in the current era of combination HIV prevention and treatment, underscores the need for prevention tailored to high-risk pregnant and breast-feeding women

    Human and Non-Human Primate Intestinal FcRn Expression and Immunoglobulin G Transcytosis

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    PURPOSE: To evaluate transcytosis of immunoglobulin G (IgG) by the neonatal Fc receptor (FcRn) in adult primate intestine to determine whether this is a means for oral delivery of monoclonal antibodies (mAbs). METHODS: Relative regional expression of FcRn and localization in human intestinal mucosa by RT-PCR, ELISA & immunohistochemistry. Transcytosis of full-length mAbs (sandwich ELISA-based detection) across human intestinal segments mounted in Ussing-type chambers, human intestinal (caco-2) cell monolayers grown in transwells, and serum levels after regional intestinal delivery in isoflurane-anesthetized cynomolgus monkeys. RESULTS: In human intestine, there was an increasing proximal-distal gradient of mucosal FcRn mRNA and protein expression. In cynomolgus, serum mAb levels were greater after ileum-proximal colon infusion than after administration to stomach or proximal small intestine (1–5 mg/kg). Serum levels of wild-type mAb dosed into ileum/proximal colon (2 mg/kg) were 124 ± 104 ng/ml (n = 3) compared to 48 ± 48 ng/ml (n = 2) after a non-FcRn binding variant. In vitro, mAb transcytosis in polarized caco-2 cell monolayers and was not enhanced by increased apical cell surface IgG binding to FcRn. An unexpected finding in primate small intestine, was intense FcRn expression in enteroendocrine cells (chromagranin A, GLP-1 and GLP-2 containing). CONCLUSIONS: In adult primates, FcRn is expressed more highly in distal intestinal epithelial cells. However, mAb delivery to that region results in low serum levels, in part because apical surface FcRn binding does not influence mAb transcytosis. High FcRn expression in enteroendocrine cells could provide a novel means to target mAbs for metabolic diseases after systemic administration
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