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1.
J Family Med Prim Care ; 11(3): 828-832, 2022 Mar.
Article in English | MEDLINE | ID: covidwho-1753780

ABSTRACT

HIV with coexisting Hepatitis C infection has been a global health problem. HIV with Hepatitis C prevalence is significantly higher in people living with HIV. These patients being immunocompromised are at higher risk of contracting COVID-19 infection. Super added COVID-19 infection may prove to be fatal in these patients. We decided to review literature for assessing the clinical manifestations and management of these patients contracting COVID-19 infection and explore the public health measures in practice in the current scenario. Practices of safety norms against COVID-19 shall prevent associated health morbidity and mortality. Moreover, management of these patients needs to be judiciously done by Physicians as COVID-19 infection may worsen their condition. The Public Health Specialist are playing a crucial role in management of COVID-19 pandemic especially by strategy planning for surveillance, health education and preparedness for any future wave of COVID-19 infection.

2.
Front Med Technol ; 3: 705875, 2021.
Article in English | MEDLINE | ID: covidwho-1630580

ABSTRACT

Nucleoside analogs are very effective antiviral agents with currently over 25 compounds approved for the therapy of viral infections. Still, their successful use against RNA viruses is very recent, despite RNA viruses comprising some of the most damaging human pathogens (e.g., Coronaviruses, Influenza viruses, or Flaviviridae such as dengue, Zika and hepatitis C viruses). The breakthrough came in 2013-2014, when the nucleoside analog Sofosbuvir became one of the cornerstones of current curative treatments for hepatitis C virus (HCV). An analog designed on the same principles, Remdesivir, has been the first approved compound against SARS-CoV-2, the coronavirus that causes the current COVID-19 pandemic. Both of these nucleoside analogs target the RNA-dependent RNA polymerase (RdRp) (NS5B for HCV, nsp12 for SARS-CoV-2). RdRps of RNA viruses display a peculiar elaboration of the classical polymerase architecture that leads to their active site being caged. Thus, triphosphate nucleosides and their analogs must access this active site in several steps along a narrow and dynamic tunnel. This makes straightforward computational approaches such as docking unsuitable for getting atomic-level details of this process. Here we give an account of ribose-modified nucleoside analogs as inhibitors of viral RdRps and of why taking into account the dynamics of these polymerases is necessary to understand nucleotide selection by RdRps. As a case study we use a computational protocol we recently described to examine the approach of the NTP tunnel of HCV NS5B by cellular metabolites of Sofosbuvir. We find major differences with natural nucleotides even at this early stage of nucleotide entry.

3.
Viruses ; 13(11)2021 10 20.
Article in English | MEDLINE | ID: covidwho-1538529

ABSTRACT

Viruses are obligate parasites that depend on a host cell for replication and survival. Consequently, to fully understand the viral processes involved in infection and replication, it is fundamental to study them in the cellular context. Often, viral infections induce significant changes in the subcellular organization of the host cell due to the formation of viral factories, alteration of cell cytoskeleton and/or budding of newly formed particles. Accurate 3D mapping of organelle reorganization in infected cells can thus provide valuable information for both basic virus research and antiviral drug development. Among the available techniques for 3D cell imaging, cryo-soft X-ray tomography stands out for its large depth of view (allowing for 10 µm thick biological samples to be imaged without further thinning), its resolution (about 50 nm for tomographies, sufficient to detect viral particles), the minimal requirements for sample manipulation (can be used on frozen, unfixed and unstained whole cells) and the potential to be combined with other techniques (i.e., correlative fluorescence microscopy). In this review we describe the fundamentals of cryo-soft X-ray tomography, its sample requirements, its advantages and its limitations. To highlight the potential of this technique, examples of virus research performed at BL09-MISTRAL beamline in ALBA synchrotron are also presented.


Subject(s)
Tomography, X-Ray/methods , Virus Diseases/virology , Virus Physiological Phenomena , Animals , Antiviral Agents/pharmacology , Humans , Tomography, X-Ray/instrumentation , Virus Diseases/diagnostic imaging , Virus Diseases/drug therapy , Viruses/chemistry , Viruses/drug effects
4.
J Hosp Infect ; 115: 51-58, 2021 Sep.
Article in English | MEDLINE | ID: covidwho-1379144

ABSTRACT

BACKGROUND: Occurrence of hepatitis C virus (HCV) infection is reduced by effective risk management procedures, but patient-to-patient transmission continues to be reported in healthcare settings. AIM: To report the use of phylogenetic analysis in the clinical risk management of an HCV outbreak among 128 thalassaemia outpatients followed at a thalassaemia centre of an Italian hospital. METHODS: Epidemiological investigation and root-cause analysis were performed. All patients with acute hepatitis and known chronic infection were tested for HCV RNA, HCV genotyping, and NS3, NS5A, and NS5B HCV genomic region sequencing. To identify transmission clusters, phylogenetic trees were built for each gene employing Bayesian methods. FINDINGS: All patients with acute hepatitis were infected with HCV genotype 1b. Root-cause analysis, including a lookback procedure, excluded blood donors as the source of HCV transmission. The phylogenetic analysis, conducted on seven patients with acute infection and eight patients with chronic infection, highlighted four transmission clusters including at least one patient with chronic and one patient with acute HCV infection. All patients in the same cluster received a blood transfusion during the same day. Two patients with acute hepatitis spontaneously cleared HCV within four weeks and nine patients received ledipasvir plus sofosbuvir for six weeks, all achieving a sustained virological response. CONCLUSION: Combined use of root-cause analysis and molecular epidemiology was effective in ascertaining the origin of the HCV outbreak. Antiviral therapy avoided the chronic progression of the infection and further spread in care units and in the family environment.


Subject(s)
Hepatitis C , Thalassemia , Antiviral Agents/therapeutic use , Bayes Theorem , Disease Outbreaks , Genotype , Hepacivirus/genetics , Hepatitis C/epidemiology , Humans , Italy/epidemiology , Phylogeny , Risk Management , Thalassemia/complications , Thalassemia/epidemiology , Thalassemia/therapy
5.
Int J Mol Sci ; 22(13)2021 Jun 26.
Article in English | MEDLINE | ID: covidwho-1304664

ABSTRACT

Hepatitis C virus (HCV) is one of the main triggers of chronic liver disease. Despite tremendous progress in the HCV field, there is still no vaccine against this virus. Potential vaccines can be based on its recombinant proteins. To increase the humoral and, especially, cellular immune response to them, more effective adjuvants are needed. Here, we evaluated a panel of compounds as potential adjuvants using the HCV NS5B protein as an immunogen. These compounds included inhibitors of polyamine biosynthesis and urea cycle, the mTOR pathway, antioxidants, and cellular receptors. A pronounced stimulation of cell proliferation and interferon-γ (IFN-γ) secretion in response to concanavalin A was shown for antioxidant N-acetylcysteine (NAC), polyamine biosynthesis inhibitor 2-difluoromethylornithine (DFMO), and TLR9 agonist CpG ODN 1826 (CpG). Their usage during the immunization of mice with the recombinant NS5B protein significantly increased antibody titers, enhanced lymphocyte proliferation and IFN-γ production. NAC and CpG decreased relative Treg numbers; CpG increased the number of myeloid-derived suppressor cells (MDSCs), whereas neither NAC nor DFMO affected MDSC counts. NAC and DFMO suppressed NO and interleukin 10 (IL-10) production by splenocytes, while DFMO increased the levels of IL-12. This is the first evidence of immunomodulatory activity of NAC and DFMO during prophylactic immunization against infectious diseases.


Subject(s)
Acetylcysteine/pharmacology , Adjuvants, Immunologic/pharmacology , Eflornithine/pharmacology , Hepatitis C/immunology , Immunity, Active/drug effects , Viral Nonstructural Proteins/immunology , Animals , Cell Proliferation , Cells, Cultured , Female , Immunogenicity, Vaccine/drug effects , Interferon-gamma/metabolism , Interleukin-10/metabolism , Interleukin-12/metabolism , Mice , Mice, Inbred DBA , Myeloid-Derived Suppressor Cells/drug effects , Myeloid-Derived Suppressor Cells/immunology , Nitric Oxide/metabolism , Oligodeoxyribonucleotides/pharmacology , T-Lymphocytes, Regulatory/drug effects , T-Lymphocytes, Regulatory/immunology , Viral Hepatitis Vaccines/immunology
6.
Viruses ; 13(5)2021 05 04.
Article in English | MEDLINE | ID: covidwho-1302483

ABSTRACT

Hepatitis C virus (HCV) is a serious and growing public health problem despite recent developments of antiviral therapeutics. To achieve global elimination of HCV, an effective cross-genotype vaccine is needed. The failure of previous vaccination trials to elicit an effective cross-reactive immune response demands better vaccine antigens to induce a potent cross-neutralizing response to improve vaccine efficacy. HCV E1 and E2 envelope (Env) glycoproteins are the main targets for neutralizing antibodies (nAbs), which aid in HCV clearance and protection. Therefore, a molecular-level understanding of the nAb responses against HCV is imperative for the rational design of cross-genotype vaccine antigens. Here we summarize the recent advances in structural studies of HCV Env and Env-nAb complexes and how they improve our understanding of immune recognition of HCV. We review the structural data defining HCV neutralization epitopes and conformational plasticity of the Env proteins, and the knowledge applicable to rational vaccine design.


Subject(s)
Epitopes/immunology , Hepacivirus/immunology , Hepatitis C Antigens/chemistry , Vaccine Development , Viral Hepatitis Vaccines/chemistry , Animals , Antibodies, Neutralizing/immunology , Cross Reactions , Epitopes/chemistry , Genotype , Hepacivirus/genetics , Hepatitis C Antibodies/immunology , Hepatitis C Antigens/immunology , Humans , Mice , Vaccine Efficacy , Viral Hepatitis Vaccines/analysis
7.
Viruses ; 13(6)2021 05 29.
Article in English | MEDLINE | ID: covidwho-1282636

ABSTRACT

An effective vaccine for the hepatitis C virus (HCV) is a major unmet medical and public health need, and it requires an antigen that elicits immune responses to multiple key conserved epitopes. Decades of research have generated a number of vaccine candidates; based on these data and research through clinical development, a vaccine antigen based on the E1E2 glycoprotein complex appears to be the best choice. One bottleneck in the development of an E1E2-based vaccine is that the antigen is challenging to produce in large quantities and at high levels of purity and antigenic/functional integrity. This review describes the production and characterization of E1E2-based vaccine antigens, both membrane-associated and a novel secreted form of E1E2, with a particular emphasis on the major challenges facing the field and how those challenges can be addressed.


Subject(s)
Hepacivirus/chemistry , Hepatitis C/prevention & control , Viral Envelope Proteins/chemistry , Viral Hepatitis Vaccines/chemistry , Animals , Epitopes/immunology , HEK293 Cells , Hepacivirus/genetics , Hepacivirus/immunology , Hepatitis C/virology , Humans , Mice , Models, Molecular , Protein Conformation , Protein Multimerization , Viral Envelope Proteins/immunology , Viral Envelope Proteins/metabolism
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