45 research outputs found

    CD4+ T Cell Depletion during all Stages of HIV Disease Occurs Predominantly in the Gastrointestinal Tract

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    The mechanisms underlying CD4+ T cell depletion in human immunodeficiency virus (HIV) infection are not well understood. Comparative studies of lymphoid tissues, where the vast majority of T cells reside, and peripheral blood can potentially illuminate the pathogenesis of HIV-associated disease. Here, we studied the effect of HIV infection on the activation and depletion of defined subsets of CD4+ and CD8+ T cells in the blood, gastrointestinal (GI) tract, and lymph node (LN). We also measured HIV-specific T cell frequencies in LNs and blood, and LN collagen deposition to define architectural changes associated with chronic inflammation. The major findings to emerge are the following: the GI tract has the most substantial CD4+ T cell depletion at all stages of HIV disease; this depletion occurs preferentially within CCR5+ CD4+ T cells; HIV-associated immune activation results in abnormal accumulation of effector-type T cells within LNs; HIV-specific T cells in LNs do not account for all effector T cells; and T cell activation in LNs is associated with abnormal collagen deposition. Taken together, these findings define the nature and extent of CD4+ T cell depletion in lymphoid tissue and point to mechanisms of profound depletion of specific T cell subsets related to elimination of CCR5+ CD4+ T cell targets and disruption of T cell homeostasis that accompanies chronic immune activation

    Islet Oxygen Consumption Rate (OCR) Dose Predicts Insulin Independence in Clinical Islet Autotransplantation

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    Background: Reliable in vitro islet quality assessment assays that can be performed routinely, prospectively, and are able to predict clinical transplant outcomes are needed. In this paper we present data on the utility of an assay based on cellular oxygen consumption rate (OCR) in predicting clinical islet autotransplant (IAT) insulin independence (II). IAT is an attractive model for evaluating characterization assays regarding their utility in predicting II due to an absence of confounding factors such as immune rejection and immunosuppressant toxicity. Methods: Membrane integrity staining (FDA/PI), OCR normalized to DNA (OCR/DNA), islet equivalent (IE) and OCR (viable IE) normalized to recipient body weight (IE dose and OCR dose), and OCR/DNA normalized to islet size index (ISI) were used to characterize autoislet preparations (n = 35). Correlation between pre-IAT islet product characteristics and II was determined using receiver operating characteristic analysis. Results: Preparations that resulted in II had significantly higher OCR dose and IE dose (p<0.001). These islet characterization methods were highly correlated with II at 6–12 months post-IAT (area-under-the-curve (AUC) = 0.94 for IE dose and 0.96 for OCR dose). FDA/PI (AUC = 0.49) and OCR/DNA (AUC = 0.58) did not correlate with II. OCR/DNA/ISI may have some utility in predicting outcome (AUC = 0.72). Conclusions: Commonly used assays to determine whether a clinical islet preparation is of high quality prior to transplantation are greatly lacking in sensitivity and specificity. While IE dose is highly predictive, it does not take into account islet cell quality. OCR dose, which takes into consideration both islet cell quality and quantity, may enable a more accurate and prospective evaluation of clinical islet preparations

    Ten golden rules for optimal antibiotic use in hospital settings: the WARNING call to action

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    Antibiotics are recognized widely for their benefits when used appropriately. However, they are often used inappropriately despite the importance of responsible use within good clinical practice. Effective antibiotic treatment is an essential component of universal healthcare, and it is a global responsibility to ensure appropriate use. Currently, pharmaceutical companies have little incentive to develop new antibiotics due to scientific, regulatory, and financial barriers, further emphasizing the importance of appropriate antibiotic use. To address this issue, the Global Alliance for Infections in Surgery established an international multidisciplinary task force of 295 experts from 115 countries with different backgrounds. The task force developed a position statement called WARNING (Worldwide Antimicrobial Resistance National/International Network Group) aimed at raising awareness of antimicrobial resistance and improving antibiotic prescribing practices worldwide. The statement outlined is 10 axioms, or “golden rules,” for the appropriate use of antibiotics that all healthcare workers should consistently adhere in clinical practice

    d-β-Hydroxybutyrate and melatonin for treatment of porcine hemorrhagic shock and injury: a melatonin dose-ranging study

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    Abstract Objective Treatment with a combination of d-β-hydroxybutyrate (BHB) and melatonin (M) improves survival in hemorrhagic shock models. Our objective was to find the most effective melatonin concentration in combination with 4 molar BHB (4 M BHB). Survival and markers of organ injury were analyzed in pigs exposed to pulmonary contusion, liver crush injury, and hemorrhagic shock and treated with lactated Ringer’s solution; 4 M BHB/43 mM M; 4 M BHB/20 mM M; 4 M BHB/10 mM M; 4 M BHB/4.3 mM M; or 4 M BHB/0.43 mM M. This work is an extension of a previously published research study. Results Survival was highest in pigs receiving 4 M BHB/43 mM M (13/14), followed by lactated Ringer’s solution (11/16) and BHB/M with decreased melatonin concentrations (4 M BHB/20 mM M 3/6, 4 M BHB/10 mM M 2/6, 4 M BHB/4.3 mM M 3/6, 4 M BHB/0.43 mM M 1/6, p = 0.011). High mortality was associated with increases in serum lactate, higher liver and muscle injury markers and decreases in PaO2:FiO2 ratios. Our study indicates that treatment with 4 M BHB and melatonin concentrations below 43 mM lack the survival benefit observed from 4 M BHB/43 mM melatonin in pigs experiencing hemorrhagic shock and polytrauma

    The impact of using an intraoperative goal directed fluid therapy protocol on clinical outcomes in patients undergoing total pancreatectomy and islet cell autotransplantation.

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    BACKGROUND: Patients undergoing total pancreatectomy and islet cell autotransplant (TPIAT) for treatment of pancreatitis are at risk for complications of over and under resuscitation. We hypothesized that using a goal directed fluid therapy (GDFT) protocol might impact clinical outcomes. MATERIALS AND METHODS: A consecutive series of adult patients undergoing TPIAT were managed intraoperatively using either standard fluid therapy (SFT, n = 44) or GDFT (n = 23) as part of a pilot study between January 2013 and May 2015. Patient characteristics, intraoperative, and postoperative data were recorded prospectively, then retrospectively analyzed for differences between the groups. RESULTS: The GDFT group had lower total fluid resuscitation (3,240 cc vs 5,173 cc, p \u3c 0.0001) and transfusion requirements (1.0 cc/kg vs 3.3 cc/kg, p = 0.050) compared to the SFT group. The pre to postop nadir hemoglobin change was significantly less for GDFT (4.2 vs 5.1 gm/dl, p = 0.021) despite less transfusion. CONCLUSIONS: Compared to SFT, using an intraoperative GDFT protocol in TPIAT patients was associated with significantly decreased intraoperative fluid resuscitation, blood transfusion and less postoperative dilutional anemia, without any difference in complications of underresuscitation. This pilot study suggests that GDFT is likely safe and further investigation is warranted
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