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1.
Liver Transpl ; 30(7): 728-741, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38315053

RESUMO

Chronic HCV infection induces interferon and dysregulates immune responses through inflammation and chronic antigenic stimulation. Antiviral drugs can cure HCV, providing a unique opportunity to examine the immunological restoration that does and does not occur when a chronic viral infection is eradicated. We quantified blood cytokines levels and used mass cytometry to immunophenotype peripheral blood mononuclear cells before and after HCV cure in 2 groups of patients and controls. At baseline, serum interferon α and soluble CD163 (a macrophage product) were elevated in both liver transplant and nonliver transplant patients compared to controls; the frequencies of several peripheral blood mononuclear cell populations differed from controls; and programmed death protein 1-positivity was increased in nearly all T cell subsets. Many abnormalities persisted after HCV cure, including elevated programmed death protein 1 expression on CD4 naïve and central memory T cells, elevated soluble CD163, and expansion of the plasmablast/plasma cell compartment. Several myeloid-lineage subsets, including Ag-presenting dendritic cells, remained dysregulated. In mechanistic studies, interferon α treatment increased programmed death protein 1 on human T cells and increased T cell receptor signaling. The data identify immunological abnormalities that persist after curative HCV treatment. Before cure, high levels of interferon α may stimulate programmed death protein 1 expression on human T cells, causing persistent functional changes.


Assuntos
Antígenos CD , Antígenos de Diferenciação Mielomonocítica , Antivirais , Hepatite C Crônica , Interferon-alfa , Transplante de Fígado , Humanos , Transplante de Fígado/efeitos adversos , Masculino , Antivirais/uso terapêutico , Pessoa de Meia-Idade , Feminino , Antígenos CD/imunologia , Antígenos CD/sangue , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/sangue , Antígenos de Diferenciação Mielomonocítica/imunologia , Hepatite C Crônica/imunologia , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/sangue , Hepatite C Crônica/cirurgia , Interferon-alfa/uso terapêutico , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/imunologia , Receptores de Superfície Celular/sangue , Receptores de Superfície Celular/imunologia , Adulto , Estudos de Casos e Controles , Idoso , Hepacivirus/imunologia , Hepacivirus/efeitos dos fármacos , Leucócitos Mononucleares/imunologia , Citocinas/sangue , Imunofenotipagem , Resultado do Tratamento
2.
BMC Gastroenterol ; 22(1): 542, 2022 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-36575373

RESUMO

BACKGROUND: Accurate rectal tumor staging guides the choice of treatment options. EUS and MRI are the main modalities for staging. AIM OF THE WORK: To compare the performance of EUS and MRI for loco-regional staging of anorectal cancer after neo-adjuvant therapy. METHODS: Seventy-three (37 male, 36 female) patients with rectal cancer after neo-adjuvant chemoradiotherapy were enrolled. Histopathological staging after surgery were used as reference for comparing the yield of loco-regional staging for EUS and MRI. EUS and MRI were done 1 month after completion of neo-adjuvant therapy. RESULTS: Regarding post-surgical T staging, eight patients had early tumor (T2 = 16 and T1 = 9) and thirty six were locally advanced (T3 = 36), while N staging, forty patients with negative nodes and 33 were positive (N1 = 22 and N2 = 11). Comparing EUS to MRI, it showed a higher sensitivity (95.7% vs. 78.7%), specificity (84.6% vs. 68.0%) and accuracy (91.8% vs. 75.3%) for staging early and locally advanced tumor. Also, it had a higher sensitivity (78.8% vs. 69.7%), specificity (75.0% vs. 65.0%) and accuracy (76.7% vs. 67.1%) for detection of lymph nodes. CONCLUSION: EUS appears to be more accurate than MRI in loco-regional staging of rectal carcinoma after neo-adjuvant therapy.


Assuntos
Neoplasias do Ânus , Neoplasias Retais , Humanos , Masculino , Feminino , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/terapia , Neoplasias Retais/patologia , Terapia Neoadjuvante , Endossonografia/métodos , Neoplasias do Ânus/patologia , Estadiamento de Neoplasias , Imageamento por Ressonância Magnética/métodos , Sensibilidade e Especificidade
3.
Molecules ; 27(20)2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36296626

RESUMO

Herein, we report the synthesis of spinel cobalt oxide nanorods (Co3O4 NRs) by a modified co-precipitation approach and examine their larvicidal activity against Culex pipiens. The structure and morphology of the as-prepared Co3O4 NRs were emphasized using X-ray diffraction (XRD), Raman spectroscopy, energy dispersive X-ray spectroscopy (EDAX), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). It was found that Co3O4 nanostructures have a face-centered spinel cubic crystal structure with a mean crystallite size of 38 nm. These nanostructures have a rod like shape with a mean diameter of 30 nm and an average length of 60 nm. The TGA measurements revealed the high stability of the formed spinel cubic structure at 400 °C. The optical behavior indicates the direct transition of electrons through an optical band gap in the range of 2.92-3.08 eV. These unique chemical and physical properties of Co3O4 NRs enabled them to be employed as a strong agent for killing the C. pipiens. A comparison study was employed between the as-prepared Co3O4 and the entomopathogenic fungus Metarhizium brunneum as a control agent of C. pipiens larvae. The results revealed that the as-prepared nanorods have higher mortality against C. pipiens larvae compared with the well-known M. brunneum.


Assuntos
Culex , Metarhizium , Nanotubos , Animais , Larva/microbiologia , Nanotubos/química , Esporos Fúngicos
4.
PLoS Pathog ; 15(7): e1007935, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31356648

RESUMO

Plasmacytoid dendritic cells (pDCs) are "natural" interferon α (IFNα)-producing cells. Despite their importance to antiviral defense, autoimmunity, and ischemic liver graft injury, because DC subsets are rare and heterogeneous, basic questions about liver pDC function and capacity to make cytokines remain unanswered. Previous investigations failed to consistently detect IFNα mRNA in HCV-infected livers, suggesting that pDCs may be incapable of producing IFNα. We used a combination of molecular, biochemical, cytometric, and high-dimensional techniques to analyze DC frequencies/functions in liver and peripheral blood mononuclear cells (PBMCs) of hepatitis C virus (HCV)-infected patients, to examine correlations between DC function and gene expression of matched whole liver tissue and liver mononuclear cells (LMCs), and to determine if pDCs can produce multiple cytokines. T cells often produce multiple cytokines/chemokines but until recently technical limitations have precluded tests of polyfunctionality in individual pDCs. Mass cytometry (CyTOF) revealed that liver pDCs are the only LMC that produces detectable amounts of IFNα in response TLR-7/8 stimulation. Liver pDCs secreted large quantities of IFNα (~2 million molecules of IFNα/cell/hour) and produced more IFNα than PBMCs after stimulation, p = 0.0001. LMCs secreted >14-fold more IFNα than IFNλ in 4 hours. Liver pDC frequency positively correlated with whole liver expression of "IFNα-response" pathway (R2 = 0.58, p = 0.007) and "monocyte surface" signature (R2 = 0.54, p = 0.01). Mass cytometry revealed that IFNα-producing pDCs were highly polyfunctional; >90% also made 2-4 additional cytokines/chemokines of our test set of 10. Liver BDCA1 DCs, but not BDCA3 DCs, were similarly polyfunctional. pDCs from a healthy liver were also polyfunctional. Our data show that liver pDCs retain the ability to make abundant IFNα during chronic HCV infection and produce many other immune modulators. Polyfunctional liver pDCs are likely to be key drivers of inflammation and immune activation during chronic HCV infection.


Assuntos
Citocinas/biossíntese , Células Dendríticas/imunologia , Hepatite C Crônica/imunologia , Interferon-alfa/biossíntese , Idoso , Antígenos CD1/sangue , Antígenos CD1/metabolismo , Antígenos de Superfície/sangue , Antígenos de Superfície/metabolismo , Quimiocinas/biossíntese , Células Dendríticas/classificação , Células Dendríticas/patologia , Feminino , Glicoproteínas/sangue , Glicoproteínas/metabolismo , Hepatite C Crônica/sangue , Hepatite C Crônica/patologia , Humanos , Interferon-alfa/sangue , Interferon gama/biossíntese , Interferon gama/sangue , Fígado/imunologia , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Trombomodulina
5.
Arch Virol ; 166(10): 2673-2682, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34297222

RESUMO

Traditional veterinary virus vaccines, such as inactivated and live-attenuated vaccines, have achieved tremendous success in controlling many viral diseases of livestock and chickens worldwide. However, many recent viral outbreaks caused by different emerging and re-emerging viruses continue to be reported annually worldwide. It is therefore necessary to develop new control regimens. Nanoparticle research has received considerable attention in the last two decades as a promising platform with significant success in veterinary medicine, replacing traditional viral vector vaccines. However, the field of nanoparticle applications is still in its initial phase of growth. Here, we discuss various preparation methods, characteristics, physical properties, antiviral effects, and pharmacokinetics of well-developed nanoparticles and the potential of nanoparticles or nano-vaccines as a promising antiviral platform for veterinary medicine.


Assuntos
Antivirais/uso terapêutico , Nanopartículas/uso terapêutico , Medicina Veterinária , Viroses/veterinária , Animais , Antivirais/química , Antivirais/classificação , Galinhas , Gado , Nanopartículas/química , Nanopartículas/classificação , Preparações Farmacêuticas , Vacinas Virais/química , Vacinas Virais/classificação , Vacinas Virais/uso terapêutico , Viroses/tratamento farmacológico , Viroses/prevenção & controle , Vírus/efeitos dos fármacos , Vírus/imunologia
6.
Microbiol Immunol ; 63(2): 77-84, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30680771

RESUMO

Hepatitis B virus (HBV) infection is a serious nosocomial infection that affects patients undergoing hemodialysis (HD). However, certain HBV variants are not detected by routine serological tests in Egyptian dialysis units because of mutations that change important viral antigens (Ags). Of note, these mutations can result in the appearance of different HBV variants with different clinical manifestations. Thus, the present study aimed to assess different clinical forms of HBV infections and viral genotypes among patients undergoing HD in the Ismailia governorate of Egypt. To this end, serum samples were collected from 150 patients undergoing HD and screened for HBV-DNA using a nested PCR technique. Positive samples were then screened for HBV serological markers (hepatitis B core antibody [HBcAb], hepatitis B surface antigen, hepatitis B surface antibody, hepatitis B e antigen and hepatitis B e antibody) using ELISA and the HBV viral load quantitated by qPCR. HBV genotypes were detected by direct sequencing of the partial surface (S) gene. The most common clinical form of HBV infection in our study cohort was overt HBV infection (10%); followed by seropositive occult hepatitis B infection (7.3%), most of whom had an isolated HBcAb. The least common form was the precore mutant (1.3%). All HBV isolates were genotype D. This study reveals the importance of HBcAb and PCR in screening for HBV, especially for detection of occult hepatitis B infection.


Assuntos
Genótipo , Vírus da Hepatite B/isolamento & purificação , Vírus da Hepatite B/patogenicidade , Hepatite B/diagnóstico , Hepatite B/virologia , Diálise Renal , Adulto , Sequência de Bases , DNA Viral/análise , DNA Viral/isolamento & purificação , Egito/epidemiologia , Feminino , Hepatite B/epidemiologia , Hepatite B/imunologia , Anticorpos Anti-Hepatite B/sangue , Antígenos da Hepatite B/genética , Antígenos de Superfície da Hepatite B/sangue , Antígenos E da Hepatite B/sangue , Vírus da Hepatite B/classificação , Vírus da Hepatite B/genética , Hepatite B Crônica/diagnóstico , Hepatite B Crônica/epidemiologia , Hepatite B Crônica/imunologia , Hepatite B Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Filogenia , Prevalência , Reação em Cadeia da Polimerase em Tempo Real , Testes Sorológicos , Carga Viral
7.
Hepatology ; 66(2): 357-370, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-27642141

RESUMO

Hepatitis C virus (HCV) is unique among RNA viruses in its ability to establish chronic infection in the majority of exposed adults. HCV persists in the liver despite interferon (IFN)-stimulated gene (ISG) induction; robust induction actually predicts treatment failure and viral persistence. It is unclear which forms of HCV RNA are associated with ISG induction and IFN resistance during natural infections. To thoroughly delineate HCV RNA populations, we developed conditions that fully separate the strands of long double-stranded RNA (dsRNA) and allow the released RNAs to be quantified in reverse transcription/polymerase chain reaction assays. These methods revealed that dsRNA, a pathogen-associated molecular pattern (PAMP), comprised 52% (standard deviation, 28%) of the HCV RNA in the livers of patients with chronic infection. HCV dsRNA was proportionally higher in patients with the unfavorable IL28B TT (rs12979860) genotype. Higher ratios of HCV double-stranded to single-stranded RNA (ssRNA) correlated positively with ISG induction. In Huh-7.5 cells, IFN treatment increased the total amount of HCV dsRNA through a process that required de novo viral RNA synthesis and shifted the ratio of viral dsRNA/ssRNA in favor of dsRNA. This shift was blocked by ribavirin (RBV), an antiviral drug that reduces relapse in HCV patients. Northern blotting established that HCV dsRNA contained genome-length minus strands. CONCLUSION: HCV dsRNA is the predominant form in the HCV-infected liver and has features of both a PAMP and a genomic reservoir. Interferon treatment increased rather than decreased HCV dsRNA. This unexpected finding suggests that HCV produces dsRNA in response to IFN, potentially to antagonize antiviral defenses. (Hepatology 2017;66:357-370).


Assuntos
Antivirais/farmacologia , Hepacivirus/genética , Hepatite C/patologia , Interferon-alfa/farmacologia , RNA de Cadeia Dupla/genética , Adulto , Biópsia por Agulha , Western Blotting , Células Cultivadas , Feminino , Citometria de Fluxo , Hepacivirus/efeitos dos fármacos , Hepatite C/tratamento farmacológico , Hepatite C/genética , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Humanos , Imuno-Histoquímica , Masculino , RNA de Cadeia Dupla/efeitos dos fármacos , RNA Viral/efeitos dos fármacos , RNA Viral/genética , Valores de Referência , Sensibilidade e Especificidade
8.
J Hepatol ; 63(6): 1323-33, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26220749

RESUMO

BACKGROUND & AIMS: Although patients infected by genotype 1b hepatitis C virus (HCV) with Q(70) and/or M(91)core gene mutations have an almost five-fold increased risk of developing hepatocellular carcinoma (HCC) and increased insulin resistance, the absence of a suitable experimental system has precluded direct experimentation on the effects of these mutations on cellular gene expression. METHODS: HuH7 cells were treated long-term with human serum to induce differentiation and to produce a model system for testing high-risk and control HCV. For clinical validation, profiles of infected cells were compared to each other and to those of liver biopsies of patients with early-stage HCV-related cirrhosis followed prospectively for up to 23 years (n=216). RESULTS: Long-term culture in human serum produced growth-arrested, hepatocyte-like cells whose gene profile overlapped significantly with that of primary human hepatocytes. High-risk (Q(70)/M(91)) and control (R(70)/L(91)) viruses had dramatically different effects on gene expression of these cells. The high-risk virus enhanced expression of pathways associated with cancer and type II diabetes, while the control virus enhanced pathways associated with oxidative phosphorylation. Of special clinical relevance, the transcriptome of cells replicating the high-risk virus correlated significantly with an HCC high-risk profile in patients (Bonferroni-corrected p=0.03), whereas no such association was observed for non-HCC-related clinical outcomes. CONCLUSIONS: The cell-based system allowed direct head-to-head comparison of HCV variants, and provided experimental support for previous clinical data indicating an oncogenic effect of core gene mutations. This simple experimental system distinguished HCV variants and will enable future mechanistic analysis and exploration of interventional approaches.


Assuntos
Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/virologia , Genes Virais , Hepacivirus/genética , Hepacivirus/patogenicidade , Antígenos do Núcleo do Vírus da Hepatite B/genética , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/virologia , Mutação , Proteínas do Core Viral/genética , Técnicas de Cultura de Células , Diferenciação Celular , Linhagem Celular , Variação Genética , Genótipo , Hepacivirus/fisiologia , Hepatite C Crônica/complicações , Hepatite C Crônica/virologia , Hepatócitos/metabolismo , Hepatócitos/patologia , Hepatócitos/virologia , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/virologia , Oncogenes , Estudos Prospectivos , Fatores de Risco , Transcriptoma , Virulência/genética , Replicação Viral
9.
Hepatology ; 58(2): 555-63, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23281009

RESUMO

UNLABELLED: Hepatocellular carcinoma (HCC) is one of the common sequelae of hepatitis C virus (HCV) infection. It remains controversial, however, whether HCV itself plays a direct role in the development of HCC. Although HCV core, NS3, and NS5A proteins were reported to display tumorigenic activities in cell culture and experimental animal systems, their clinical impact on HCC development in humans is still unclear. In this study we investigated sequence polymorphisms in the core protein, NS3, and NS5A of HCV genotype 1b (HCV-1b) in 49 patients who later developed HCC during a follow-up of an average of 6.5 years and in 100 patients who did not develop HCC after a 15-year follow-up. Sequence analysis revealed that Gln at position 70 of the core protein (core-Gln(70) ), Tyr at position 1082 plus Gln at 1112 of NS3 (NS3-Tyr(1082) /Gln(1112) ), and six or more mutations in the interferon/ribavirin resistance-determining region of NS5A (NS5A-IRRDR≥6) were significantly associated with development of HCC. Multivariate analysis identified core-Gln(70) , NS3-Tyr(1082) /Gln(1112) , and α-fetoprotein (AFP) levels (>20 ng/L) as independent factors associated with HCC. Kaplan-Meier analysis revealed a higher cumulative incidence of HCC for patients infected with HCV isolates with core-Gln(70) , NS3-Tyr(1082) /Gln(1112) or both than for those with non-(Gln(70) plus NS3-Tyr(1082) /Gln(1112) ). In most cases, neither the residues at position 70 of the core protein nor positions 1082 and 1112 of the NS3 protein changed during the observation period. CONCLUSION: HCV isolates with core-Gln(70) and/or NS3-Tyr(1082) /Gln(1112) are more closely associated with HCC development compared to those with non-(Gln(70) plus NS3-Tyr(1082) /Gln(1112) ).


Assuntos
Carcinoma Hepatocelular/virologia , Hepacivirus/genética , Hepatite C Crônica/virologia , Neoplasias Hepáticas/virologia , Proteínas do Core Viral/genética , Proteínas não Estruturais Virais/genética , Sequência de Aminoácidos , Carcinoma Hepatocelular/epidemiologia , Feminino , Seguimentos , Predisposição Genética para Doença , Genótipo , Hepatite C Crônica/complicações , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/epidemiologia , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Análise Multivariada , Polimorfismo Genético , Fatores de Risco , Proteínas do Core Viral/análise , Proteínas não Estruturais Virais/análise
10.
Viruses ; 16(7)2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-39066223

RESUMO

Since the emergence of the SARS-CoV-2 virus in 2019, nearly 700 million COVID-19 cases and 7 million deaths have been reported globally. Despite most individuals recovering within four weeks, the Center for Disease Control (CDC) estimates that 7.5% to 41% develop post-acute infection syndrome (PAIS), known as 'Long COVID'. This review provides current statistics on Long COVID's prevalence, explores hypotheses concerning epidemiological factors, such as age, gender, comorbidities, initial COVID-19 severity, and vaccine interactions, and delves into potential mechanisms, including immune responses, viral persistence, and gut dysbiosis. Moreover, we conclude that women, advanced age, comorbidities, non-vaccination, and low socioeconomic status all appear to be risk factors. The reasons for these differences are still not fully understood and likely involve a complex relationship between social, genetic, hormonal, and other factors. Furthermore, individuals with Long COVID-19 seem more likely to endure economic hardship due to persistent symptoms. In summary, our findings further illustrate the multifaceted nature of Long COVID and underscore the importance of understanding the epidemiological factors and potential mechanisms needed to develop effective therapeutic strategies and interventions.


Assuntos
COVID-19 , Síndrome de COVID-19 Pós-Aguda , SARS-CoV-2 , Humanos , COVID-19/epidemiologia , Fatores de Risco , Comorbidade , Prevalência , Feminino , Masculino , Disbiose
11.
Viruses ; 16(1)2024 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-38257839

RESUMO

Since its discovery in 2019, SARS-CoV-2 still makes the headline news [...].


Assuntos
COVID-19 , Vírus de RNA , Humanos , SARS-CoV-2/genética , COVID-19/epidemiologia , Evolução Biológica
12.
Heliyon ; 10(15): e34857, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39166002

RESUMO

This paper presents a mathematical optimization framework for the strategic placement of quasi-dynamic wireless charging (QWC) stations within road networks to address the charging needs of battery electric buses (BEBs). This study evaluates two scenarios for powering the buses. In the first scenario, a grid-connected system is considered. The optimization aims to minimize annual costs related to capital, operation, and energy losses of the electric bus fleet. This involves determining the optimal locations for QWC stations, the length of power transmitters, and the corresponding battery capacities for the BEBs. Using MATLAB-based optimization tools Casadi and Yalmip, with solvers Bonmin and Fmincon, the optimal configuration includes a 13 kWh battery capacity and a 300 m power transmitter distributed across five bus stop areas. The second scenario employs a chance-constrained optimization approach for an isolated solar photovoltaic (PV) and battery energy storage system (BESS). This system is designed to reliably meet the BEBs' energy requirements throughout the day, considering different seasonal data (winter, summer, all seasons/year-round). The optimization results for the PV and BESS capacities vary with the seasons: 394.247 kW and 2012.6 kWh using summer data, 1762.1 kW and 2738.2 kWh using winter data, and 1610.8 kW and 2741.9 kWh using year-round data. Additionally, the paper examines the impact of varying bus fleet sizes on the optimal battery size and power transmitter combination using a real-world example of the bus route between Khalifa City and Abu Dhabi Downtown in the UAE. The findings suggest that larger batteries with fewer or no charging stations are more economical for smaller fleets. Conversely, as the fleet size increases, a combination of smaller battery sizes and a greater number (and length) of QWC (power transmitters) becomes more cost-effective. This research offers significant insights into the efficient deployment of QWC stations and the integration of renewable energy and energy storage for sustainable urban electric bus networks. The proposed optimization models provide a systematic approach to designing and operating charging infrastructure, contributing to sustainable urban transportation systems. Moreover, the study highlights the influence of seasonal data on PV system sizing and costs.

13.
Life (Basel) ; 14(2)2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38398672

RESUMO

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has affected millions worldwide since its outbreak in the winter of 2019. While extensive research has primarily focused on the deleterious respiratory effects of SARS-CoV-2 in recent years, its pan-tropism has become evident. Among the vital organs susceptible to SARS-CoV-2 infection is the kidney. Post SARS-CoV-2 infection, patients have developed coronavirus disease 19 (COVID-19), with reported incidences of COVID-19 patients developing acute kidney injury (AKI). Given COVID-19's multisystemic manifestation, our review focuses on the impact of SARS-CoV-2 infection within the renal system with an emphasis on the current hypotheses regarding the role of extracellular vesicles (EVs) in SARS-CoV-2 pathogenesis. Emerging studies have shown that SARS-CoV-2 can directly infect the kidney, whereas EVs are involved in the spreading of SARS-CoV-2 particles to other neighboring cells. Once the viral particles are within the kidney system, many proinflammatory signaling pathways are shown to be activated, resulting in AKI. Hence, clinical investigation of urinary proinflammatory components and total urinary extracellular vesicles (uEVs) with viral particles have been used to assess the severity of AKI in patients with COVID-19. Remarkedly, new emerging studies have shown the potential of mesenchymal stem cell-derived EVs (MSC-EVs) and ACE2-containing EVs as a hopeful therapeutic tool to inhibit SARS-CoV-2 RNA replication and block viral entry, respectively. Overall, understanding EVs' physiological role is crucial and hopefully will rejuvenate our therapeutic approach towards COVID-19 patients with AKI.

14.
J Pediatr Surg ; 59(8): 1486-1497, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38692944

RESUMO

BACKGROUND: Pediatric surgeons have faced esophageal reconstruction challenges for decades owing to a variety of congenital and acquired conditions. This work aimed to introduce a reproducible and efficient approach for creating tissue-engineered esophageal tissue using bone marrow mesenchymal stem cells (BMSCs) cultured in preconditioned mediums seeded on a sheep decellularized tunica vaginalis (DTV) scaffold for partial reconstruction of a rabbit's esophagus. METHODS: DTV was performed using SDS and Triton X-100 solutions. The decellularized grafts were employed alone (DTV group) or after recellularization with BMSCs cultured for 10 days in preconditioned mediums (RTV group) for reconstructing a 3 cm segmental defect in the cervical esophagus of rabbits (n = 20) after the decellularization process was confirmed. Rabbits were observed for one month, after which they were euthanized, and the reconstructed esophagi were harvested for histological analysis. RESULTS: Six rabbits in the DTV group and eight rabbits in the RTV group survived until the end of the one-month study period. Despite histological examination demonstrating that both grafts completely repaired the esophageal defect, the RTV graft demonstrated a histological structure similar to that of the normal esophagus. The reconstructed esophagi in the RTV group revealed the arrangement of the different layers of the esophageal wall with the formation of newly formed blood vessels and Schwann-like cells. CONCLUSION: DTV xenograft is a novel scaffold that promotes cell adhesion and differentiation and might be effectively utilized for regenerating esophageal tissue, paving the way for future clinical trials in pediatric patients.


Assuntos
Esôfago , Engenharia Tecidual , Alicerces Teciduais , Animais , Coelhos , Engenharia Tecidual/métodos , Esôfago/cirurgia , Ovinos , Esofagoplastia/métodos , Transplante de Células-Tronco Mesenquimais/métodos
15.
Am J Physiol Gastrointest Liver Physiol ; 305(5): G375-82, 2013 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-23812037

RESUMO

Liver fibrosis, with subsequent development of cirrhosis and ultimately portal hypertension, results in the death of patients with end-stage liver disease if liver transplantation is not performed. Hepatic stellate cells (HSCs), central mediators of liver fibrosis, resemble tissue pericytes and regulate intrahepatic blood flow by modulating pericapillary resistance. Therefore, HSCs can contribute to portal hypertension in patients with chronic liver disease (CLD). We have previously demonstrated that activated HSCs express functional chemokine receptor, CXCR4, and that receptor engagement by its ligand, CXCL12, which is increased in patients with CLD, leads to further stellate cell activation in a CXCR4-specific manner. We therefore hypothesized that CXCL12 promotes HSC contraction in a CXCR4-dependent manner. Stimulation of HSCs on collagen gel lattices with CXCL12 led to gel contraction and myosin light chain (MLC) phosphorylation, which was blocked by addition of AMD3100, a CXCR4 small molecule inhibitor. These effects were further mediated by the Rho kinase pathway since both Rho kinase knockdown or Y-27632, a Rho kinase inhibitor, blocked CXCL12 induced phosphorylation of MLC and gel contraction. BAPTA-AM, a calcium chelator, had no effect, indicating that this pathway is calcium sensitive but not calcium dependent. In conclusion, CXCL12 promotes stellate cell contractility in a predominantly calcium-independent fashion. Our data demonstrates a novel role of CXCL12 in stellate cell contraction and the availability of small molecule inhibitors of the CXCL12/CXCR4 axis justifies further investigation into its potential as therapeutic target for portal hypertension.


Assuntos
Cálcio/metabolismo , Forma Celular/efeitos dos fármacos , Quimiocina CXCL12/farmacologia , Células Estreladas do Fígado/efeitos dos fármacos , Actinas/metabolismo , Animais , Linhagem Celular , Quelantes/farmacologia , Colágeno/metabolismo , Relação Dose-Resposta a Droga , Géis , Células Estreladas do Fígado/metabolismo , Células Estreladas do Fígado/patologia , Humanos , Camundongos , Cadeias Leves de Miosina/metabolismo , Fenótipo , Fosforilação , Inibidores de Proteínas Quinases/farmacologia , Interferência de RNA , Receptores CXCR4/efeitos dos fármacos , Receptores CXCR4/genética , Receptores CXCR4/metabolismo , Proteínas Recombinantes/farmacologia , Transdução de Sinais/efeitos dos fármacos , Transfecção , Quinases Associadas a rho/antagonistas & inibidores , Quinases Associadas a rho/genética , Quinases Associadas a rho/metabolismo
16.
Dig Dis ; 31(5-6): 421-5, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24281015

RESUMO

OBJECTIVES: This study explores viral factors of the interferon (IFN) and ribavirin (RBV) resistance-determining region (IRRDR), the IFN sensitivity-determining region (ISDR) and the core protein, and host factor interleukin 28B associated with response to pegylated IFN (PEG-IFN) and RBV combination therapy, and the correlation of viral and host factors with IFN-λ1. METHODS: A total of 58 patients underwent PEG-IFN/RBV combination therapy for 48 weeks. The pretreatment factors associated with rapid virological response (RVR) and sustained virological response (SVR) were analyzed. Pretreatment IFN-λ1 serum levels were compared with the viral and host factors. RESULTS: Univariate analysis showed that IRRDR ≥6 and ISDR ≥2 were significant pretreatment predictors of RVR, and multivariate analysis identified IRRDR ≥6 and hemoglobin as significant predictors of SVR. Pretreatment IFN-λ1 was significantly higher in the SVR group than in the non-SVR group and also in the IRRDR ≥6 group than in the IRRDR ≤5 group. CONCLUSIONS: IRRDR ≥6 was the only significant predictor of SVR and was correlated with IFN-λ1. High serum levels of IFN-λ1 may be conducive to effective PEG-IFN/RBV combination therapy because of the immunomodulatory system.


Assuntos
Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/virologia , Interferons/farmacologia , Interferons/uso terapêutico , Polietilenoglicóis/química , Ribavirina/farmacologia , Ribavirina/uso terapêutico , Quimioterapia Combinada , Feminino , Humanos , Interferons/química , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Fatores de Risco , Resultado do Tratamento
17.
Dig Dis ; 31(5-6): 426-33, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24281016

RESUMO

OBJECTIVE: We investigated the impact of host genetics represented by the single nucleotide polymorphism (SNP) of the IL28B gene and viral genetic variations within the nonstructural protein 5A (NS5A) [including the interferon (IFN)/ribavirin (RBV) resistance-determining region (IRRDR) and the IFN sensitivity-determining region (ISDR)] on the outcome of pegylated IFN and RBV (PEG-IFN/RBV) treatment. METHODS: Sixty-six patients infected with hepatitis C virus (HCV)-2a or HCV-2b who received PEG-IFN/RBV for 24 weeks were examined. RESULTS: In HCV-2a, the major genotype of IL28B SNP showed a tendency toward association with sustained virological response (SVR) and rapid virological response (RVR), and four or more mutations in IRRDR (IRRDR[2a] ≥4) and one or more mutations in ISDR plus its carboxyl-flanking region (ISDR/+C[2a] ≥1) were significantly associated with SVR and RVR. In HCV-2b, one or more mutations in the N-terminal part of IRRDR (IRRDR/N[2b] ≥1) were significantly associated with RVR. Multivariate analysis identified the major genotype of IL28B SNP and IRRDR[2a] ≥4 as independent predictive factors of SVR in HCV-2a, with IRRDR[2a] ≥4 being more powerful than the IL28B SNP. Also, IRRDR[2a] ≥4 in HCV-2a and IRRDR/N[2b] ≥1 in HCV-2b were significant determiners of RVR. CONCLUSION: The NS5A sequence heterogeneity and IL28B SNP are useful factors to predict the sensitivity to PEG-IFN/RBV therapy in HCV-2a and HCV-2b infections.


Assuntos
Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/genética , Interferons/uso terapêutico , Ribavirina/farmacologia , Ribavirina/uso terapêutico , Carga Viral/genética , Sequência de Aminoácidos , Sequência de Bases , Demografia , Quimioterapia Combinada , Feminino , Hepatite C Crônica/virologia , Humanos , Interferons/química , Interferons/farmacologia , Interleucinas/metabolismo , Cinética , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Polietilenoglicóis/química , Fatores de Risco , Análise de Sequência de DNA , Resultado do Tratamento , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/genética
18.
Dig Dis ; 31(5-6): 434-9, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24281017

RESUMO

OBJECTIVES: We assessed the outcome of double-filtration plasmapheresis (DFPP) combined with pegylated interferon (PEG-IFN) and ribavirin (RBV) therapy in patients infected with hepatitis C virus (HCV)-1b whose HCV had not disappeared during PEG-IFN/RBV combination therapy, or who had relapsed after the end of the therapy. Additionally, we investigated factors predictive of sustained virological response (SVR), including host and viral genetic factors, to DFPP plus IFN/RBV therapy. METHODS: A total of 40 patients infected with HCV-1b whose HCV virus had not been eradicated by previous PEG-IFN/RBV therapy were enrolled for treatment by DFPP plus IFN/RBV. Rapid virological response (RVR) and SVR were assessed, and pretreatment factors associated with SVR - the interleukin (IL)28B gene, the IFN/RBV resistance-determining region (IRRDR) and the IFN sensitivity-determining region (ISDR) - were analyzed. RESULTS: Of the 40 patients, 9 (23%) achieved RVR and 10 (25%) achieved SVR. The significant factors associated with SVR were IL28B major and RVR, as assessed by multivariate analysis (p = 0.0182, p = 0.0005). CONCLUSION: Patients whose HCV is not eradicated by previous PEG-IFN/RBV would be good candidates for combined DFPP and IFN/RBV retreatment provided they demonstrate IL28B major and have achieved RVR.


Assuntos
Filtração , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/virologia , Interferons/uso terapêutico , Plasmaferese , Polietilenoglicóis/química , Ribavirina/uso terapêutico , Quimioterapia Combinada , Feminino , Humanos , Interferons/química , Interleucinas/metabolismo , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Resultado do Tratamento
19.
Microorganisms ; 11(12)2023 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-38138096

RESUMO

Acute hepatitis is defined as an inflammation or injury in the hepatocytes that continues for a short period of time (less than 6 months) [...].

20.
J Clin Microbiol ; 50(12): 3886-92, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22993188

RESUMO

Hepatitis C virus genotype 4 (HCV-4) is the cause of approximately 20% of the 180 million cases of chronic hepatitis C in the world. HCV-4 infection is common in the Middle East and Africa, with an extraordinarily high prevalence in Egypt. Viral genetic polymorphisms, especially within core and NS5A regions, have been implicated in influencing the response to pegylated-interferon and ribavirin (PEG-IFN/RBV) combination therapy in HCV-1 infection. However, this has not been confirmed in HCV-4 infection. Here, we investigated the impact of heterogeneity of NS5A and core proteins of HCV-4, mostly subtype HCV-4a, on the clinical outcomes of 43 Egyptian patients treated with PEG-IFN/RBV. Sliding window analysis over the carboxy terminus of NS5A protein identified the IFN/RBV resistance-determining region (IRRDR) as the most prominent region associated with sustained virological response (SVR). Indeed, 21 (84%) of 25 patients with SVR, but only 5 (28%) of 18 patients with non-SVR, were infected with HCV having IRRDR with 4 or more mutations (IRRDR ≥ 4) (P = 0.0004). Multivariate analysis identified IRRDR ≥ 4 as an independent SVR predictor. The positive predictive value of IRRDR ≥ 4 for SVR was 81% (21/26; P = 0.002), while its negative predictive value for non-SVR was 76% (13/17; P = 0.02). On the other hand, there was no significant correlation between core protein polymorphisms, either at residue 70 or at residue 91, and treatment outcome. In conclusion, the present results demonstrate for the first time that IRRDR ≥ 4, a viral genetic heterogeneity, would be a useful predictive marker for SVR in HCV-4 infection when treated with PEG-IFN/RBV.


Assuntos
Antivirais/uso terapêutico , Variação Genética , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Interferons/uso terapêutico , Ribavirina/uso terapêutico , Proteínas não Estruturais Virais/genética , Egito , Genótipo , Hepacivirus/isolamento & purificação , Hepatite C Crônica/virologia , Humanos , Dados de Sequência Molecular , Valor Preditivo dos Testes , Prognóstico , Análise de Sequência de DNA , Resultado do Tratamento
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