Foreign body-related complications are rare but possibly fatal events in clinical practice. Liver abscess as a result of gastrointestinal perforation caused by foreign bodies is even more rare. We report a case of a 63-year-old man who was admitted with fever and left epigastric pain.
View Article and Find Full Text PDFPediatr Crit Care Med
April 2024
Objectives: Profound dengue shock syndrome (DSS) complicated by severe respiratory failure necessitating mechanical ventilation (MV) accounts for high case fatality rates among PICU-admitted patients. A major challenge to management is the assessment of intravascular volume, which can be hampered by severe plasma leakage and the use of MV.
Design: Retrospective cohort, from 2013 to 2021.
Binding of anti-HIV antibodies (Abs) to envelope (Env) glycoproteins on infected cells can mark them for elimination via antibody-dependent cell-mediated cytotoxicity (ADCC). BST2, a type I interferon (IFN)-stimulated restriction factor that anchors nascent Env-containing virions at the surface of infected cells has been shown to enhance ADCC functions. In a comprehensive analysis of ADCC potency by neutralizing anti-HIV Abs (NAbs), we show in this study that NAbs are capable of mediating ADCC against HIV-infected T cells with 3BNC117, PGT126 and PG9 being most efficient.
View Article and Find Full Text PDFThe plasma membrane protects the cell from its surroundings and regulates cellular communication, homing, and metabolism. Not surprisingly, the composition of this membrane is highly controlled through the vesicular trafficking of proteins to and from the cell surface. As intracellular pathogens, most viruses exploit the host plasma membrane to promote viral replication while avoiding immune detection.
View Article and Find Full Text PDFBackground: Hepatitis C virus (HCV) can replicate in cells of the immune system and productively propagate in primary T lymphocytes in vitro. We aimed to determine whether exposure to authentic, patient-derived HCV can modify the proliferation capacity, susceptibility to apoptosis and phenotype of T cells.
Methods: Primary total T cells from a healthy donor were used as targets and plasma-derived HCV from patients with chronic hepatitis C served as inocula.
Background: HIV proteins Nef and Vpu down-modulate various host factors to evade immune defenses. Indeed, the CD4 receptor is down-regulated by Nef and Vpu, whereas virion-tethering BST2 is depleted by Vpu. Antibody-dependent cell-mediated cytotoxicity (ADCC) is increasingly recognized as a potentially powerful anti-HIV response.
View Article and Find Full Text PDFHIV-1 Vpr triggers NK cell-mediated lysis of infected cells by upregulating ULBP2, a ligand of the NKG2D receptor, through activation of the ATR-mediated DNA damage response. Herein, we demonstrate that Vpr augments ULBP2 expression on both infected and uninfected bystander cells during HIV-1 infection of primary CD4+ T lymphocytes. Indeed, the frequency of uninfected bystander cells expressing high levels of ULBP2 was elevated in a Vpr-dependent manner.
View Article and Find Full Text PDFBased on investigations of liver biopsy material, certain cellular genes have been implicated as correlates of success or failure to interferon alpha-ribavirin (IFN/RBV) therapy against hepatitis C. The current study aimed at determining whether expression of host genes thought to be relevant to HCV replication in the liver would be correlated with HCV infection status in peripheral blood mononuclear cells (PBMCs) and also with patient responsiveness to IFN/RBV treatment. Therefore, PBMCs from patients with chronic hepatitis C responding (n = 35) or not (n = 49) to IFN/RBV and from healthy controls (n = 15) were evaluated for HCV RNA load and cellular gene expression.
View Article and Find Full Text PDFHepatitis C virus (HCV) is one of the main causes of chronic liver disease. Although infection of hepatocytes is mainly responsible for manifestations of hepatitis C, the virus also invades the immune system by a yet-to-be-identified mechanism. Using human T cell lines and primary T lymphocytes as targets and patient-derived HCV as inocula, we aimed to identify how HCV gains entry into these cells.
View Article and Find Full Text PDFJ Clin Exp Hepatol
December 2011
Hepatitis C virus (HCV) can persist in the liver, lymphoid (immune) cells, and serum of individuals long after an apparently complete therapy-induced or a spontaneous resolution of hepatitis C. This essential asymptomatic infection, called secondary occult HCV infection (OCI), usually occurs in anti-HCV antibody reactive individuals with normal liver function tests. This infection has been identified when the nucleic acid amplification assays of enhanced sensitivity were applied for the detection of HCV genome and its replication.
View Article and Find Full Text PDFHIV-1 viral protein R (Vpr) from laboratory-adapted virus strains activates the DNA damage/stress sensor ATR kinase and induces cell cycle arrest at the G(2)/M phase through a process that requires Vpr to engage the DDB1-CUL4A (VprBP/DCAF-1) E3 ligase complex. Activation of this DNA damage/stress checkpoint in G(2) by Vpr was shown to modulate NKG2D-dependent NK cell effector functions via enhancing expression of NKG2D ligands, notably ULBP2. However, it is unknown whether Vpr from HIV-1 primary isolates (groups M, N, O, and P) could modulate NKG2D-mediated cytotoxic functions of NK cells.
View Article and Find Full Text PDFHepatitis C virus (HCV) infection causes significant morbidity, and efficient mouse models would greatly facilitate virus studies and the development of effective vaccines and new therapeutic agents. Entry factors, innate immunity, and host factors needed for viral replication represent the initial barriers that restrict HCV infection of mouse cells. Experiments in this paper consider early postentry steps of viral infection and investigate the roles of interferon regulatory factors (IRF-3 and IRF-9) and microRNA (miR-122) in promoting HCV replication in mouse embryo fibroblasts (MEFs) that contain viral subgenomic replicons.
View Article and Find Full Text PDFOccult hepatitis C virus infection (OCI) is a recently identified entity of which the existence became evident when nucleic acid amplification assays of enhanced sensitivity were introduced for the detection of hepatitis C virus (HCV) genome and its replication. This form of HCV infection has been found to persist in the presence of antibodies against HCV and normal levels of liver enzymes for years after spontaneous or antiviral therapy-induced resolution of hepatitis C and, therefore, can be termed as secondary OCI. HCV RNA in OCI circulate at fluctuating levels normally not exceeding 200 genome copies per millilitre of serum or plasma, while low levels of virus genome and its replicative intermediate RNA-negative strand are detectable in the liver and, importantly, immune cells, which provide an opportunity to detect active virus replication without the need for acquiring a liver biopsy.
View Article and Find Full Text PDFHepatitis C virus (HCV) was discovered in 1989. HCV is a positive single-strand RNA. We all have thought, that HCV can replicate only in liver tissue, but now we know, that HCV can replicate in extrahepatic tissue as well.
View Article and Find Full Text PDFHIV up-regulates cell-surface expression of specific ligands for the activating NKG2D receptor, including ULBP-1, -2, and -3, but not MICA or MICB, in infected cells both in vitro and in vivo. However, the viral factor(s) involved in NKG2D ligand expression still remains undefined. HIV-1 Vpr activates the DNA damage/stress-sensing ATR kinase and promotes G(2) cell-cycle arrest, conditions known to up-regulate NKG2D ligands.
View Article and Find Full Text PDFUnlabelled: Hepatitis C virus (HCV) can persist in the liver, lymphoid cells, and serum of individuals with apparently complete spontaneous or therapy-induced resolution of hepatitis C and can replicate in vivo and in vitro in human T cells. The current study was aimed at assessing the infectivity of HCV persisting at very low levels using the previously established HCV infection system in human T cells. Naive lymphoid cells were exposed to plasma and/or supernatants from cultured peripheral blood mononuclear cells from nine individuals with apparent sustained virological response after completion of antiviral therapy.
View Article and Find Full Text PDFBackground & Aims: Infection of the lymphatic system by hepatitis C virus (HCV) appears to be an intrinsic characteristic of chronic hepatitis C (CHC) and low-level (occult) HCV infection, but the subsets of immune cells involved were not defined. The aim of this study was to characterize HCV replication status and to assess virus compartmentalization in CD4+ and CD8+ T lymphocytes, B cells, and monocytes in CHC, and silent infection persisting after resolution of hepatitis C.
Methods: Immune cell subtypes isolated from 7 patients with CHC and 7 individuals with occult infection were analyzed for HCV-RNA-positive and -negative strands and, in selected cases, nonstructural protein 5A display and HCV variants.
A novel class of platinum(II) complexes of pyridine sulfide derivatives of triazine was synthesized, characterized, and investigated using the human breast cancer cell line, MDA-MB-468. S-30 was one of the most potent derivatives of its class (IC(50), 0.39 microM) eliciting the greatest biological response.
View Article and Find Full Text PDFAntibodies against virus nucleocapsid (anticore) normally accompany hepadnaviral hepatitis but they may also occur in the absence of symptoms and other serological indicators of the infection. This situation can be encountered following a clinically and serologically unapparent exposure to hepatitis B virus (HBV) or after recovery from hepatitis B. In this study, woodchucks inoculated with woodchuck hepatitis virus (WHV) were investigated to determine the relationship between anticore detection and the molecular status of virus replication in a primary WHV surface antigen (WHsAg)-negative infection or long-after resolution of WHV hepatitis.
View Article and Find Full Text PDFIt is presumed that resolution of hepatitis C, as evidenced by normalization of liver function tests and disappearance of hepatitis C virus (HCV) RNA from serum, as determined by conventional laboratory assays, reflects virus eradication. In this study, we examined the expression of the HCV genome in the sera, peripheral blood mononuclear cells (PBMC), and, on some occasions, monocyte-derived dendritic cells (DC) long after resolution of hepatitis C by using a highly sensitive reverse transcription (RT)-PCR-nucleic acid hybridization (RT-PCR-NAH) assay. The samples obtained from 16 randomly selected patients (5 with spontaneous and 11 with treatment-induced resolution), monitored for up to 5 years, were studied by qualitative and semiquantitative RT-PCR-NAH and by real-time RT-PCR to detect the HCV RNA positive strand.
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