249 research outputs found

    Foetal arrhythmias: an enigma of the missed beats

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    Background: The synchronised depolarization and repolarisation of the atria and ventricles is achieved by specialised cardiac cells that generate an electrical impulse and propagate it along the conducting system in the myocardial tissue, leading to rhythmic activity of the atria and ventricles. Abnormalities of these rhythms lead to foetal arrhythmia.Methods: A retrospective observational study was conducted in a tertiary care hospital over period of one year to study the course and perinatal outcome of women with foetal arrhythmias.Results: The confinement in the study period was N=4302, of which 207(4.81%) women had foetal congenital malformations. Among them 21(0.48%) women had foetal cardiovascular abnormalities and 6(0.14%) women had foetal arrhythmias. There were two cases of maternal primary Sjogrens syndrome: one with foetal 2nddegree atrioventricular (AV) heart block with 2:1 AV conduction and another with foetal 3rd degree or complete heart block. Others were a case of Atrial premature contractions with compensatory pause, a case of Supraventricular tachycardia, one case of sinus tachycardia with non-immune hydrops and a case of foetal bradyarrhythmia with regular ectopic beats in a case of complex congenital heart disease. The course of these pregnancies, treatment options and perinatal outcome was studied.Conclusions: Foetal echocardiography and Doppler are effective tools for detection and monitoring of foetal arrhythmias. Early and correct diagnoses of arrhythmias help in management of foetal arrhythmias and multidisciplinary team-based approach gives optimum treatment results

    Host-Directed Drug Therapies for Neglected Tropical Diseases Caused by Protozoan Parasites

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    The neglected tropical diseases (NTDs) caused by protozoan parasites are responsible for significant morbidity and mortality worldwide. Current treatments using anti-parasitic drugs are toxic and prolonged with poor patient compliance. In addition, emergence of drug-resistant parasites is increasing worldwide. Hence, there is a need for safer and better therapeutics for these infections. Host-directed therapy using drugs that target host pathways required for pathogen survival or its clearance is a promising approach for treating infections. This review will give a summary of the current status and advances of host-targeted therapies for treating NTDs caused by protozoa

    Extracorporeal cellular therapy (ELAD) in severe alcoholic hepatitis: A multinational, prospective, controlled, randomized trial.

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    Severe alcoholic hepatitis (sAH) is associated with a poor prognosis. There is no proven effective treatment for sAH, which is why early transplantation has been increasingly discussed. Hepatoblastoma-derived C3A cells express anti-inflammatory proteins and growth factors and were tested in an extracorporeal cellular therapy (ELAD) study to establish their effect on survival for subjects with sAH. Adults with sAH, bilirubin ≥8 mg/dL, Maddrey\u27s discriminant function ≥ 32, and Model for End-Stage Liver Disease (MELD) score ≤ 35 were randomized to receive standard of care (SOC) only or 3-5 days of continuous ELAD treatment plus SOC. After a minimum follow-up of 91 days, overall survival (OS) was assessed by using a Kaplan-Meier survival analysis. A total of 203 subjects were enrolled (96 ELAD and 107 SOC) at 40 sites worldwide. Comparison of baseline characteristics showed no significant differences between groups and within subgroups. There was no significant difference in serious adverse events between the 2 groups. In an analysis of the intent-to-treat population, there was no difference in OS (51.0% versus 49.5%). The study failed its primary and secondary end point in a population with sAH and with a MELD ranging from 18 to 35 and no upper age limit. In the prespecified analysis of subjects with MELD \u3c 28 (n = 120), ELAD was associated with a trend toward higher OS at 91 days (68.6% versus 53.6%; P = .08). Regression analysis identified high creatinine and international normalized ratio, but not bilirubin, as the MELD components predicting negative outcomes with ELAD. A new trial investigating a potential benefit of ELAD in younger subjects with sufficient renal function and less severe coagulopathy has been initiated. Liver Transplantation 24 380-393 2018 AASLD

    TLR4 and NKT Cell Synergy in Immunotherapy against Visceral Leishmaniasis

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    NKT cells play an important role in autoimmune diseases, tumor surveillance, and infectious diseases, providing in most cases protection against infection. NKT cells are reactive to CD1d presented glycolipid antigens. They can modulate immune responses by promoting the secretion of type 1, type 2, or immune regulatory cytokines. Pathogen-derived signals to dendritic cells mediated via Toll like Receptors (TLR) can be modulated by activated invariant Natural Killer T (iNKT) cells. The terminal β-(1–4)-galactose residues of glycans can modulate host responsiveness in a T helper type-1 direction via IFN-γ and TLRs. We have attempted to develop a defined immunotherapeutic, based on the cooperative action of a TLR ligand and iNKT cell using a mouse model of visceral leishmaniasis. We evaluated the anti-Leishmania immune responses and the protective efficacy of the β-(1–4)-galactose terminal NKT cell ligand glycosphingophospholipid (GSPL) antigen of L. donovani parasites. Our results suggest that TLR4 can function as an upstream sensor for GSPL and provoke intracellular inflammatory signaling necessary for parasite killing. Treatment with GSPL was able to induce a strong effective T cell response that contributed to effective control of acute parasite burden and led to undetectable parasite persistence in the infected animals. These studies for the first time demonstrate the interactions between a TLR ligand and iNKT cell activation in visceral leishmaniasis immunotherapeutic

    Using a Non-Image-Based Medium-Throughput Assay for Screening Compounds Targeting N-myristoylation in Intracellular Leishmania Amastigotes

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    We have refined a medium-throughput assay to screen hit compounds for activity against N-myristoylation in intracellular amastigotes of Leishmania donovani. Using clinically-relevant stages of wild type parasites and an Alamar blue-based detection method, parasite survival following drug treatment of infected macrophages is monitored after macrophage lysis and transformation of freed amastigotes into replicative extracellular promastigotes. The latter transformation step is essential to amplify the signal for determination of parasite burden, a factor dependent on equivalent proliferation rate between samples. Validation of the assay has been achieved using the anti-leishmanial gold standard drugs, amphotericin B and miltefosine, with EC50 values correlating well with published values. This assay has been used, in parallel with enzyme activity data and direct assay on isolated extracellular amastigotes, to test lead-like and hit-like inhibitors of Leishmania Nmyristoyl transferase (NMT). These were derived both from validated in vivo inhibitors of Trypanosoma brucei NMT and a recent high-throughput screen against L. donovani NMT. Despite being a potent inhibitor of L. donovani NMT, the activity of the lead T. brucei NMT inhibitor (DDD85646) against L. donovani amastigotes is relatively poor. Encouragingly, analogues of DDD85646 show improved translation of enzyme to cellular activity. In testing the high-throughput L. donovani hits, we observed macrophage cytotoxicity with compounds from two of the four NMT-selective series identified, while all four series displayed low enzyme to cellular translation, also seen here with the T. brucei NMT inhibitors. Improvements in potency and physicochemical properties will be required to deliver attractive lead-like Leishmania NMT inhibitors

    MAP Kinase Phosphatase-2 Plays a Critical Role in Response to Infection by Leishmania mexicana

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    In this study we generated a novel dual specific phosphatase 4 (DUSP4) deletion mouse using a targeted deletion strategy in order to examine the role of MAP kinase phosphatase-2 (MKP-2) in immune responses. Lipopolysaccharide (LPS) induced a rapid, time and concentration-dependent increase in MKP-2 protein expression in bone marrow-derived macrophages from MKP-2+/+ but not from MKP-2−/− mice. LPS-induced JNK and p38 MAP kinase phosphorylation was significantly increased and prolonged in MKP-2−/− macrophages whilst ERK phosphorylation was unaffected. MKP-2 deletion also potentiated LPS-stimulated induction of the inflammatory cytokines, IL-6, IL-12p40, TNF-α, and also COX-2 derived PGE2 production. However surprisingly, in MKP-2−/− macrophages, there was a marked reduction in LPS or IFNγ-induced iNOS and nitric oxide release and enhanced basal expression of arginase-1, suggesting that MKP-2 may have an additional regulatory function significant in pathogen-mediated immunity. Indeed, following infection with the intracellular parasite Leishmania mexicana, MKP-2−/− mice displayed increased lesion size and parasite burden, and a significantly modified Th1/Th2 bias compared with wild-type counterparts. However, there was no intrinsic defect in MKP-2−/− T cell function as measured by anti-CD3 induced IFN-γ production. Rather, MKP-2−/− bone marrow-derived macrophages were found to be inherently more susceptible to infection with Leishmania mexicana, an effect reversed following treatment with the arginase inhibitor nor-NOHA. These findings show for the first time a role for MKP-2 in vivo and demonstrate that MKP-2 may be essential in orchestrating protection against intracellular infection at the level of the macrophage

    MIF Participates in Toxoplasma gondii-Induced Pathology Following Oral Infection

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    BACKGROUND: Macrophage migration inhibitory factor (MIF) is essential for controlling parasite burden and survival in a model of systemic Toxoplasma gondii infection. Peroral T. gondii infection induces small intestine necrosis and death in susceptible hosts, and in many aspects resembles inflammatory bowel disease (IBD). Considering the critical role of MIF in the pathogenesis of IBD, we hypothesized that MIF participates in the inflammatory response induced by oral infection with T. gondii. METHODOLOGY/PRINCIPAL FINDINGS: Mif deficient (Mif(-/-)) and wild-type mice in the C57Bl/6 background were orally infected with T. gondii strain ME49. Mif(-/-) mice had reduced lethality, ileal inflammation and tissue damage despite of an increased intestinal parasite load compared to wt mice. Lack of MIF caused a reduction of TNF-α, IL-12, IFN-γ and IL-23 and an increased expression of IL-22 in ileal mucosa. Moreover, suppressed pro-inflammatory responses at the ileal mucosa observed in Mif(-/-) mice was not due to upregulation of IL-4, IL-10 or TGF-β. MIF also affected the expression of matrix metalloproteinase-9 (MMP-9) but not MMP-2 in the intestine of infected mice. Signs of systemic inflammation including the increased concentrations of inflammatory cytokines in the plasma and liver damage were less pronounced in Mif(-/-) mice compared to wild-type mice. CONCLUSION/SIGNIFICANCE: In conclusion, our data suggested that in susceptible hosts MIF controls T. gondii infection with the cost of increasing local and systemic inflammation, tissue damage and death

    Laparoscopy in management of appendicitis in high-, middle-, and low-income countries: a multicenter, prospective, cohort study.

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    BACKGROUND: Appendicitis is the most common abdominal surgical emergency worldwide. Differences between high- and low-income settings in the availability of laparoscopic appendectomy, alternative management choices, and outcomes are poorly described. The aim was to identify variation in surgical management and outcomes of appendicitis within low-, middle-, and high-Human Development Index (HDI) countries worldwide. METHODS: This is a multicenter, international prospective cohort study. Consecutive sampling of patients undergoing emergency appendectomy over 6 months was conducted. Follow-up lasted 30 days. RESULTS: 4546 patients from 52 countries underwent appendectomy (2499 high-, 1540 middle-, and 507 low-HDI groups). Surgical site infection (SSI) rates were higher in low-HDI (OR 2.57, 95% CI 1.33-4.99, p = 0.005) but not middle-HDI countries (OR 1.38, 95% CI 0.76-2.52, p = 0.291), compared with high-HDI countries after adjustment. A laparoscopic approach was common in high-HDI countries (1693/2499, 67.7%), but infrequent in low-HDI (41/507, 8.1%) and middle-HDI (132/1540, 8.6%) groups. After accounting for case-mix, laparoscopy was still associated with fewer overall complications (OR 0.55, 95% CI 0.42-0.71, p < 0.001) and SSIs (OR 0.22, 95% CI 0.14-0.33, p < 0.001). In propensity-score matched groups within low-/middle-HDI countries, laparoscopy was still associated with fewer overall complications (OR 0.23 95% CI 0.11-0.44) and SSI (OR 0.21 95% CI 0.09-0.45). CONCLUSION: A laparoscopic approach is associated with better outcomes and availability appears to differ by country HDI. Despite the profound clinical, operational, and financial barriers to its widespread introduction, laparoscopy could significantly improve outcomes for patients in low-resource environments. TRIAL REGISTRATION: NCT02179112

    IL-1β Suppresses Innate IL-25 and IL-33 Production and Maintains Helminth Chronicity.

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    Approximately 2 billion people currently suffer from intestinal helminth infections, which are typically chronic in nature and result in growth retardation, vitamin A deficiency, anemia and poor cognitive function. Such chronicity results from co-evolution between helminths and their mammalian hosts; however, the molecular mechanisms by which these organisms avert immune rejection are not clear. We have found that the natural murine helminth, Heligmosomoides polygyrus bakeri (Hp) elicits the secretion of IL-1β in vivo and in vitro and that this cytokine is critical for shaping a mucosal environment suited to helminth chronicity. Indeed in mice deficient for IL-1β (IL-1β(-/-)), or treated with the soluble IL-1βR antagonist, Anakinra, helminth infection results in enhanced type 2 immunity and accelerated parasite expulsion. IL-1β acts to decrease production of IL-25 and IL-33 at early time points following infection and parasite rejection was determined to require IL-25. Taken together, these data indicate that Hp promotes the release of host-derived IL-1β that suppresses the release of innate cytokines, resulting in suboptimal type 2 immunity and allowing pathogen chronicity

    Casemix, management, and mortality of patients receiving emergency neurosurgery for traumatic brain injury in the Global Neurotrauma Outcomes Study: a prospective observational cohort study

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