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1.
Cell Microbiol ; 21(2): e12992, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30550623

RESUMEN

Lyme arthritis (LA), a late disease manifestation of Borrelia burgdorferi infection, usually resolves with antibiotic therapy. However, some patients develop proliferative synovitis lasting months to several years after spirochetal killing, called postinfectious LA. In this study, we phenotyped haematopoietic and stromal cell populations in the synovial lesion ex vivo and used these findings to generate an in vitro model of LA using patient-derived fibroblast-like synoviocytes (FLS). Ex vivo analysis of synovial tissue revealed high abundance of IFNγ-producing T cells and NK cells. Similar to marked IFNγ responses in tissue, postinfectious LA synovial fluid also had high levels of IFNγ. HLA-DR-positive FLS were present throughout the synovial lesion, particularly in areas of inflammation. FLS stimulated in vitro with B. burgdorferi, which were similar to conditions during infection, expressed 68 genes associated primarily with innate immune activation and neutrophil recruitment. In contrast, FLS stimulated with IFNγ, which were similar to conditions in the postinfectious phase, expressed >2,000 genes associated with pathogen sensing, inflammation, and MHC Class II antigen presentation, similar to the expression profile in postinfectious synovial tissue. Furthermore, costimulation of FLS with B. burgdorferi and IFNγ induced greater expression of IL-6 and other innate immune response proteins and genes than with IFNγ stimulation alone. These results suggest that B. burgdorferi infection, in combination with IFNγ, initiates the differentiation of FLS into a highly inflammatory phenotype. We hypothesise that overexpression of IFNγ by lymphocytes within synovia perpetuates these responses in the postinfectious period, causing proliferative synovitis and stalling appropriate repair of damaged tissue.


Asunto(s)
Fibroblastos/citología , Interferón gamma/inmunología , Enfermedad de Lyme/inmunología , Sinoviocitos/citología , Sinovitis/inmunología , Borrelia burgdorferi/inmunología , Diferenciación Celular/inmunología , Humanos , Enfermedad de Lyme/patología , Membrana Sinovial/metabolismo , Linfocitos T/inmunología
2.
Retrovirology ; 13: 15, 2016 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-26969150

RESUMEN

BACKGROUND: LILRA3 is an immunostimulatory molecule which can conditionally induce the proliferation of cytotoxic cells. LILRA3 has a deletion genotype which is associated with multiple immune disorders. In this study, we wanted to analyze the regulation of LILRA3 and its significance in the context of HIV infection. RESULTS: We analyzed a panel of TLR agonists and found that ssRNA40, a TLR8 agonist, is a potent inducer of LILRA3 in healthy individuals. However, this regulation is much diminished in HIV. Comparison of TLR8 to TLR4 induction of LILRA3 indicated that LPS induces less LILRA3 than ssRNA40 among healthy controls, but not HIV patients. Levels of LILRA3 induction correlated to virus load and CD4 counts in untreated patients. Recombinant LILRA3 can induce a host of proinflammatory genes which include IL-6 and IL-1α, as well as alter the expression of MHC and costimulatory molecules in monocytes and B-cells. CONCLUSION: Our experiments point towards a beneficial role for LILRA3 in virus infections, especially in ssRNA viruses, like HIV, that engage TLR8. However, the potentially beneficial role of LILRA3 is abrogated during a HIV infection. We believe that more work has to be done to study the role of LILRA3 in infectious diseases and that there is a potential for exploring the use of LILRA3 in the treatment of virus infections.


Asunto(s)
Regulación de la Expresión Génica , Infecciones por VIH/patología , VIH/aislamiento & purificación , Monocitos/inmunología , Receptores Inmunológicos/metabolismo , Carga Viral , Adulto , Recuento de Linfocito CD4 , Femenino , Infecciones por VIH/inmunología , Humanos , Masculino , Persona de Mediana Edad , Monocitos/metabolismo , Receptor Toll-Like 8/metabolismo
3.
Microorganisms ; 12(8)2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39203346

RESUMEN

Convalescent sera, rich in pathogen-specific antibodies, offers passive immunity to patients with infectious diseases. Screening assays using convalescent sera are crucial for evaluating therapeutic efficacy, selecting suitable serum donors, and standardizing assays. They measure antibody levels, neutralizing potential, and specificity against viruses like SARS-CoV-2, ensuring therapeutic serum contains potent antibodies. Standardized procedures enable reliable results and wider adoption of serum therapy for COVID-19. We have developed a high-content image-based assay for screening convalescent sera against SARS-CoV-2 variants. Using various cell lines, we identified optimal candidates, employed immunofluorescence to visualize infected cells, and assessed neutralizing antibody efficacy. Screening convalescent sera for therapeutic potential identified neutralizing activity against SARS-CoV-2 variants. Dose-response analysis showed variable neutralizing activity, with some sera exhibiting broad neutralization. Additionally, we explored the synergy between neutralizing sera and ß-d-N4-hydroxycytidine (NHC), an initial metabolite of molnupiravir. These assays enhance serum therapy's benefits for COVID-19 treatment and aid in understanding neutralizing activity against SARS-CoV-2 variants, addressing viral challenges.

4.
Microbiol Spectr ; 12(4): e0358623, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38391232

RESUMEN

Although smallpox has been eradicated, other orthopoxviruses continue to be a public health concern as exemplified by the ongoing Mpox (formerly monkeypox) global outbreak. While medical countermeasures (MCMs) previously approved by the Food and Drug Administration for the treatment of smallpox have been adopted for Mpox, previously described vulnerabilities coupled with the questionable benefit of at least one of the therapeutics during the 2022 Mpox outbreak reinforce the need for identifying and developing other MCMs against orthopoxviruses. Here, we screened a panel of Merck proprietary small molecules and identified a novel nucleoside inhibitor with potent broad-spectrum antiviral activity against multiple orthopoxviruses. Efficacy testing of a 7-day dosing regimen of the orally administered nucleoside in a murine model of severe orthopoxvirus infection yielded a dose-dependent increase in survival. Treated animals had greatly reduced lesions in the lung and nasal cavity, particularly in the 10 µg/mL dosing group. Viral levels were also markedly lower in the UMM-766-treated animals. This work demonstrates that this nucleoside analog has anti-orthopoxvirus efficacy and can protect against severe disease in a murine orthopox model.IMPORTANCEThe recent monkeypox virus pandemic demonstrates that members of the orthopoxvirus, which also includes variola virus, which causes smallpox, remain a public health issue. While currently FDA-approved treatment options exist, risks that resistant strains of orthopoxviruses may arise are a great concern. Thus, continued exploration of anti-poxvirus treatments is warranted. Here, we developed a template for a high-throughput screening assay to identify anti-poxvirus small-molecule drugs. By screening available drug libraries, we identified a compound that inhibited orthopoxvirus replication in cell culture. We then showed that this drug can protect animals against severe disease. Our findings here support the use of existing drug libraries to identify orthopoxvirus-targeting drugs that may serve as human-safe products to thwart future outbreaks.


Asunto(s)
Mpox , Orthopoxvirus , Viruela , Virus de la Viruela , Animales , Ratones , Humanos , Nucleósidos/uso terapéutico , Viruela/tratamiento farmacológico , Viruela/prevención & control , Modelos Animales de Enfermedad
5.
Tob Induc Dis ; 222024.
Artículo en Inglés | MEDLINE | ID: mdl-38828079

RESUMEN

INTRODUCTION: Electronic cigarettes (e-cigarettes) have emerged as a new paradigm in nicotine delivery systems. Although they are marketed as safer alternatives to tobacco, public perceptions of their safety and utility vary widely. This study aims to understand the percentage of use, factors associated, perceptions, and attitudes about e-cigarettes among Ecuadorian adults. METHODS: A cross-sectional survey was conducted among the Ecuadorian population aged 18-65 years through a convenience sample, using a structured online questionnaire designed to collect responses from voluntary participants over three months, from February to April 2023. The questionnaire assessed the respondents' attitudes and perceptions towards e-cigarettes. Data were analyzed using descriptive statistics, chi-squared tests, and adjusted logistic regression analyses to identify factors associated with e-cigarette use. RESULTS: Out of a total of 3047 Ecuadorian adults, the percentage of e-cigarette ever use was 27.9% (n=850), with 19.4% being current users and 8.5% former users. A negative stance towards e-cigarettes was predominant, with 66.3% considering e-cigarette use a public health problem in Ecuador. A significant association was observed between e-cigarette use and perceived harmfulness (p<0.001). Among non-users, there was a predominant stance in favor of control measures and disapproval of e-cigarette use among minors (p<0.001). The factors associated with the use of electronic cigarettes included being health personnel (AOR=1.51; 95% CI: 1.26-1.80). Older age (aged >24 years) and a history of tobacco use were associated with lower e-cigarette use (current users, OR=0.31; 95% CI: 0.25-0.38; previous users, OR=0.23; 95% CI: 0.18-0.28). CONCLUSIONS: The findings highlight a significant percentage of e-cigarette use among Ecuadorian adults, especially among younger groups. There is a need for comprehensive public health education about e-cigarettes in Ecuador. There is strong support from the public for control measures, suggesting the potential acceptability of regulations concerning e-cigarettes.

6.
Arthritis Rheumatol ; 75(5): 782-793, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36413215

RESUMEN

OBJECTIVE: Obliterative microvascular lesions are found in the synovial tissue of ~50% of patients with post-antibiotic Lyme arthritis (LA) and correlate with autoantibodies to certain vascular antigens. In this study, we identified lymphocytes with cytotoxic potential that may also mediate this feature of synovial pathology. METHODS: The cytotoxic potential of lymphocytes and their T cell receptor (TCR) Vß gene usage were determined using samples of peripheral blood mononuclear cells (PBMCs) and synovial fluid mononuclear cells (SFMCs) from patients with antibiotic-responsive or post-antibiotic LA. Cell phenotypes were analyzed using flow cytometry and intracellular cytokine staining. Immunohistochemistry was performed on post-antibiotic synovial tissue samples. RESULTS: In SFMC and PBMC samples, the percentages of CD8+ T cells and double-negative T cells (primarily γδ T cells) were greater among 22 patients with post-antibiotic LA than in 14 patients with antibiotic-responsive LA. Moreover, CD8+ T cells and γδ T cells often expressed cytotoxic mediators, granzyme A/granzyme B, and perforin. The same 3 TCR Vß segments were over-represented in both CD4+ T cells and CD8+ T cells in SFMC samples from post-antibiotic LA patients. In synovial tissue samples from 3 patients with post-antibiotic LA, CD8+ T cells intermixed with CD4+ T cells were seen around blood vessels, and 2 patients with microvascular damage had autoantibodies to vascular-associated antigens. One of these 2 patients, the one in whom cytotoxicity appeared to be active, had complement (C5b-9) deposition on obliterated vessels. Very few natural killer cells or γδ T cells were seen. CONCLUSION: We propose that CD8+ T cell-mediated cytotoxicity, CD4+ T cell help, autoantibodies to vascular antigens, and complement deposition may each have a role in microvasculature damage in post-antibiotic LA.


Asunto(s)
Leucocitos Mononucleares , Enfermedad de Lyme , Humanos , Líquido Sinovial , Linfocitos T CD4-Positivos , Linfocitos T CD8-positivos , Enfermedad de Lyme/tratamiento farmacológico , Receptores de Antígenos de Linfocitos T alfa-beta , Antibacterianos/uso terapéutico , Autoanticuerpos
7.
Antiviral Res ; 210: 105513, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36592670

RESUMEN

Antibody-based therapy is emerging as a critical therapeutic countermeasure to treat acute viral infections by offering rapid protection against clinical disease. The advancements in structural biology made it feasible to rationalize monoclonal antibodies (mAbs) by identifying key and, possibly, neutralizing epitopes of viral proteins for therapeutic purposes. A critical component in assessing mAbs during pandemics requires the development of rapid but detailed methods to detect and quantitate the neutralization activity. In this study, we developed and optimized two high-content image (HCI)-based assays: one to detect viral proteins by staining and the second to quantify cytopathic viral effects by a label-free phenotypic assay. These assays were employed to screen for therapeutic antibodies against the monkeypox virus (MPXV) using surrogate poxviruses such as vaccinia virus (VACV). Plaque-based neutralization results confirmed the HCI data. The phenotypic assay found pox virus-induced syncytia formation in various cells, and we were able to quantitate and use this phenotype to screen mAbs. The HCI identified several potent VACV-neutralizing antibodies that showed in vitro efficacy against both clades of MPXV. In addition, a combination study of ST-246/tecovirimat/TPOXX a single neutralizing antibody Ab-40, showed synergistic activity against VACV in an in-vitro neutralization assay. This rapid high-content method utilizing state-of-the-art technologies enabled the evaluation of hundreds of mAbs quickly to identify several potent anti-MPXV neutralizing mAbs for further development.


Asunto(s)
Anticuerpos Antivirales , Monkeypox virus , Anticuerpos Neutralizantes , Virus Vaccinia/genética , Proteínas Virales , Anticuerpos Monoclonales/farmacología , Pruebas de Neutralización
8.
J Prim Care Community Health ; 14: 21501319231179936, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37291965

RESUMEN

INTRODUCTION: Job satisfaction has been shown to have important effects at the organizational level. In various corners of the world, physicians are obliged to perform a period of social service, generally at the first level of care in rural or remote areas. OBJECTIVE: To describe the level of job satisfaction and perceptions of Ecuadorian rural physicians regarding compulsory social service. METHODOLOGY: A descriptive, cross-sectional study was conducted based on a self-administered online questionnaire from February to March 2022, in Ecuadorian rural physicians who were performing their compulsory social service. Participants were invited through official outreach groups. A total of 247 surveys were included in this study. We assessed job satisfaction by means of the S20/23 job satisfaction questionnaire and compared these results with sociodemographic variables and job characteristics of the participants. We performed the reliability test (Cronbach's alpha) to find the validity of the S20/23 questionnaire in physicians performing compulsory social service. RESULTS: The majority of participants were women (61.0%), and overall job satisfaction was 4.1/7.0 pts. "indifferent." The only satisfaction factor in which a predominance of dissatisfaction was found related to benefits/remuneration (43.3%). Participants' perceptions of wrong academic guidance during training, insufficient induction, and negative experiences during work were related to higher levels of dissatisfaction (P < .05). CONCLUSION: The level of job satisfaction of Ecuadorian rural physicians during their compulsory social service was low and graduates indicated a neutral attitude toward job satisfaction in general. Negative perceptions with respect to training and expectation formation prior to and during the mandatory social service generated greater dissatisfaction. The Ministry of Health of Ecuador, as an organizational entity, should implement improvements to increase the job satisfaction of recently graduated physicians, given the implications that this experience may have for their professional future.


Asunto(s)
Médicos , Servicios de Salud Rural , Humanos , Masculino , Femenino , Estudios Transversales , Satisfacción en el Trabajo , Ecuador , Población Rural , Reproducibilidad de los Resultados , Encuestas y Cuestionarios , Servicio Social , Autoimagen
9.
J Biomed Biotechnol ; 2009: 837608, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19644560

RESUMEN

Cryptosporidium parvum, one of the most important causative organisms of human diarrheas during childhood, contains a monomeric DNA-topoisomerase IB (CpTopIB) in chromosome 7. Heterologous expression of CpTopIB gene in a budding yeast strain lacking this activity proves that the cryptosporidial enzyme is functional in vivo. The enzymatic activity is comprised in a single polypeptide, which contains all the structural features defining a fully active TopIB. Relaxation activity of the yeast extracts was detected only when CpTopIB ORF was expressed in a yeast expression system showing time and protein dependence under steady state kinetic conditions. The susceptibility of CpTopIB-transformed yeast to the irreversible inhibitor camptothecin and its water-soluble derivatives (topotecan and SN-38) was assessed.


Asunto(s)
Cryptosporidium parvum/enzimología , ADN-Topoisomerasas de Tipo I/metabolismo , Secuencia de Aminoácidos , Animales , Camptotecina/farmacología , Cryptosporidium parvum/efectos de los fármacos , Cryptosporidium parvum/genética , ADN-Topoisomerasas de Tipo I/química , ADN-Topoisomerasas de Tipo I/genética , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Proteínas Mutantes/metabolismo , Saccharomyces cerevisiae/citología , Saccharomyces cerevisiae/efectos de los fármacos , Alineación de Secuencia , Topotecan/farmacología
10.
Biochimie ; 90(9): 1325-36, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18420039

RESUMEN

LORIEN (encoding a protein that contains a SP-RING/Miz zinc-finger motif present in a group of proteins involved in the Small Ubiquitin-related Modifier -SUMO- conjugation pathway) and MAT2 (encoding the methionine adenosyltransferase -MAT-) genes are arranged as two alternating copies in a head-to-tail configuration, with the LORIEN gene as the first copy of the cluster. The 5880bp preceding the first LORIEN gene copy were compared to the same region of L. major, showing a 93% identity between them. Bioinformatic analysis of this region predicted the presence of a 747-bp ORF encoding a hypothetical protein of 248 amino acids. Transcription of this ORF was confirmed by run-on assays and RT-PCR. Expression of the LORIEN gene was tested in both the promastigote and amastigote stages. Transcription arrest evidenced that LORIEN mRNA stability was very similar in both stages of the parasite life cycle. Protein synthesis inhibition by cycloheximide led to an increase in the steady-state levels of LORIEN transcripts only during the promastigote stage, pointing out to the existence of different stage-dependent mechanisms operating on the post-transcriptional regulation of this gene. The role of the LORIEN untranslated regions (5'UTR and 3'UTR) in post-transcriptional regulation was analysed using the luciferase (luc) reporter gene. Results evidenced that the 5'UTR was responsible for a low reporter gene expression, whereas the intergenic region (IR) between LORIEN and MAT2 genes provided high luc levels. However, the 3'UTR seemed to lack regulatory elements. Basing on these results, a model of regulation for the LORIEN gene is proposed.


Asunto(s)
Región de Flanqueo 5'/genética , Leishmania infantum/enzimología , Metionina Adenosiltransferasa/metabolismo , Familia de Multigenes/genética , Proteínas Protozoarias/metabolismo , Procesamiento Postranscripcional del ARN/genética , Transcripción Genética/genética , Región de Flanqueo 3'/genética , Animales , Eliminación de Gen , Leishmania infantum/genética , Leishmania infantum/crecimiento & desarrollo , Metionina Adenosiltransferasa/genética , Proteínas Protozoarias/genética
11.
Ecotoxicol Environ Saf ; 70(2): 251-8, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17675233

RESUMEN

The biopesticide Spinosad causes a drop in cell viability in two mammalian cellular models CHO-K1 and Vero, using the neutral red incorporation assay as endpoint. Dose-response curves were assessed after 24, 48, and 72 h under different conditions i.e. presence of 10% fetal calf serum or 1% bovine serum albumin or antioxidants. The presence of antioxidant agents, viz. reduced glutathione (1 mM), vitamin C (100 microM), and vitamin E (20 microM) reduced significantly the cytotoxic effect of Spinosad, thus pointing to an oxidative damage mediated by this compound. An increase in malondialdehyde production was observed after 24-h treatment with Spinosad in both Vero and CHO-K1 cells, using fractions of NRU(50) as final concentrations. At concentrations equivalent to its NRU(20), NRU(10) and NRU(5) Spinosad caused significant alterations in the glutathione-redox cycle in the form of significant decrease in total and reduced glutathione, large increase in glutathione peroxidase activity, little induction of glutathione reductase, and significant decline of glutathione S-transferase activities.


Asunto(s)
Antioxidantes/metabolismo , Glutatión/metabolismo , Insecticidas/toxicidad , Macrólidos/toxicidad , Animales , Antioxidantes/farmacología , Ácido Ascórbico/farmacología , Células CHO , Supervivencia Celular/efectos de los fármacos , Chlorocebus aethiops , Cricetinae , Cricetulus , Combinación de Medicamentos , Glutatión/farmacología , Disulfuro de Glutatión/metabolismo , Glutatión Peroxidasa/metabolismo , Glutatión Reductasa/metabolismo , Glutatión Transferasa/metabolismo , Peroxidación de Lípido , Malondialdehído/metabolismo , Oxidación-Reducción , Células Vero , Vitamina E/farmacología
12.
Biochim Biophys Acta ; 1760(1): 10-9, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16280200

RESUMEN

Methionine adenosyltransferase (MAT: EC 2.5.1.6) catalyzes the synthesis of S-adenosylmethionine (AdoMet) in two sequential steps, AdoMet formation and subsequent tripolyphosphate (PPPi) cleavage, induced by AdoMet. In pursuit of a better understanding of the biological function of the enzyme, the MAT gene was cloned into vector PX63NEO to induce episomal overexpression in leishmania parasites. Neomycin-selected clones originated a strain of such overexpressing parasites that accumulated more than 3-fold AdoMet than mock-transfected cells and showed over ten times the wild type MAT activity, concurring with a significant accumulation of the MAT protein during the early logarithmic phase and MAT transcripts throughout the growth cycle. The rate of AdoMet efflux, practically nil in the control promastigotes, was exceptionally high in the MAT-overexpressing parasites, whilst growth in this strain was comparable to development in control cells, i.e., it was not affected by deleterious hypermethylation. Moreover, the modified strain was 10-fold more resistant to sinefungin, a S-adenosylmethionine-like antibiotic, than control cells. The effects of overexpression on polyamine metabolism and transport were likewise studied.


Asunto(s)
Leishmania donovani/enzimología , Metionina Adenosiltransferasa/genética , Adenosina/análogos & derivados , Adenosina/farmacología , Animales , Clonación Molecular , Resistencia a Medicamentos , Leishmania donovani/genética , Metionina Adenosiltransferasa/fisiología , Neomicina , Poliaminas/metabolismo , S-Adenosilmetionina/biosíntesis , Trypanosomatina/enzimología , Trypanosomatina/genética
13.
Gene ; 389(2): 163-73, 2007 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-17196769

RESUMEN

Methionine adenosyltransferase (MAT) is an important enzyme for metabolic processes, inasmuch as its product, S-adenosylmethionine (AdoMet), plays a key role in trans-methylation, trans-sulphuration and polyamine synthesis. Our prior studies have shown that the Leishmania infantum genome contains two identical copies of the gene encoding MAT (MAT2 gene), arranged in head-to-tail configuration and alternating with another gene, called LORIEN that contains a zinc-finger motif. Both genes are constitutively expressed throughout the promastigote stage of the parasite cell cycle, and their flanking regions were detected by RT-PCR. Luciferase (luc) reporter assays indicated the presence of regulatory elements within the MAT2 3'UTR and intergenic region, and fragments responsible for such regulation were identified by deletional analysis. By site-directed mutagenesis of the wild-type -42 AG recognized in the trans-splicing of the MAT2 gene, the AG slightly downstream (position -36) was observed to be able to generate the same levels of luc expression, thus suggesting that potentially this gene has alternative spliced leader acceptor sites. The stability of MAT2 and LORIEN transcripts was very similar in both logarithmic and stationary phases. However, cycloheximide (CHX) inhibition of protein synthesis increased MAT2 and LORIEN mRNA levels in the logarithmic phase only, an indication that these genes are regulated in promastigotes at the post-transcriptional level by protein factors that targets both transcripts for degradation. However, during the stationary phase, another CHX-independent factor also led to MAT2 and LORIEN mRNAs degradation, indicating the existence of different mechanisms operating on the post-transcriptional regulation of these two genes.


Asunto(s)
Regulación de la Expresión Génica , Genes Protozoarios , Leishmania infantum/enzimología , Metionina Adenosiltransferasa/genética , Estabilidad del ARN , Animales , Cicloheximida/farmacología , Genoma de Protozoos , Leishmania infantum/genética , Leishmania infantum/crecimiento & desarrollo , Estadios del Ciclo de Vida , Familia de Multigenes , Mutagénesis Sitio-Dirigida , Inhibidores de la Síntesis de la Proteína/farmacología , Estabilidad del ARN/efectos de los fármacos , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Protozoario/genética , ARN Protozoario/metabolismo , Secuencias Reguladoras de Ácidos Nucleicos , Trans-Empalme , Transcripción Genética
14.
AIDS ; 31(1): 25-34, 2017 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-27755104

RESUMEN

OBJECTIVE: The aim of this study is to analyse the influence of LILRA3 and the genetic leukocyte immunoglobulin-like receptor 3 (LILRA3) deletion on transmission and clinical course of HIV infection. DESIGN: Case and control study. METHODS: LILRA3 genotypes were determined by PCR. HIV patients were categorized into short-term progressors, normal progressors and long-term nonprogressors according to the clinical course. Functional studies were performed using real-time PCR, intracellular flow cytometry and ELISA. RESULTS: The prevalence of the homozygous LILRA3 deletion was higher in HIV-positive individuals (n = 439) than in controls (n = 651) (P = 0.02). The disease progression was faster in homozygously deleted patients with more short-term progressors than in heterozygous (P = 0.03) and homozygously positive (P = 0.002) individuals. These results have been confirmed in a seroconverter cohort (n = 288). The frequency of the homozygous deletion in the confirmation cohort was higher than in controls (P = 0.04). Combining both cohorts, the proportion of homozygously LILRA3-deleted individuals was 6.2% in HIV-infected patients (n = 727) vs. 3.2% in controls (P = 0.01). Functional analysis revealed an upregulation of the LILRA3 gene in real-time PCR in treated patients when compared with untreated patients (P = 0.007) and controls (P = 0.02) resulting in a higher LILRA3 expression in CD4 (P = 0.008) and CD14 (P = 0.02) cells of untreated patients in intracellular flow cytometry. LILRA 3 concentrations in the sera were similar between the groups, in untreated patients a correlation between viral load and LILRA3 concentration was found. CONCLUSION: The homozygous LILRA3 deletion is associated with a higher susceptibility for HIV disease and with a faster disease progression.


Asunto(s)
Predisposición Genética a la Enfermedad , Infecciones por VIH/genética , Receptores Inmunológicos/deficiencia , Eliminación de Secuencia , Adulto , Estudios de Casos y Controles , Ensayo de Inmunoadsorción Enzimática , Femenino , Citometría de Flujo , Infecciones por VIH/patología , Infecciones por VIH/transmisión , Humanos , Masculino , Reacción en Cadena de la Polimerasa , Receptores Inmunológicos/genética , Factores de Riesgo
15.
Rev. colomb. gastroenterol ; 36(2): 257-262, abr.-jun. 2021. tab, graf
Artículo en Inglés, Español | LILACS | ID: biblio-1289306

RESUMEN

Resumen El quiste mesentérico es una patología intraabdominal poco frecuente, en su mayoría benigna. El tratamiento casi siempre es quirúrgico y consiste en la resección del quiste y de los órganos involucrados siempre que sea posible con el fin de reducir la tasa de recurrencia. Se presenta el caso de un paciente de 38 años con dolor abdominal inespecífico y diagnóstico ecográfico de masa retroperitoneal zona II izquierda gigante. Los estudios de extensión incluyeron tomografía axial computarizada, resonancia magnética y endoscopia de vías digestivas altas, cuyos hallazgos informaron una lesión quística gigante. Se realizó resección quirúrgica de la lesión por vía abierta, con diagnóstico histopatológico de quiste mesentérico.


Abstract A mesenteric cyst is a rare, mostly benign, intra-abdominal tumor. Treatment is almost always surgical and consists of removing the cyst and involved organs whenever possible to prevent recurrence. The following is the case of a 38-year-old patient with nonspecific abdominal pain and an ultrasound diagnosis of a giant retroperitoneal mass in the left medial paracolic gutter. The following imaging studies were performed: computed tomography, magnetic resonance, and endoscopy, finding a giant cystic lesion. An exploratory laparotomy was performed to remove the mass, and a histopathology report confirmed the diagnosis of mesenteric cyst.


Asunto(s)
Humanos , Masculino , Adulto , Dolor Abdominal , Quiste Mesentérico , Pacientes , Espectroscopía de Resonancia Magnética , Tomografía , Endoscopía , Informe de Investigación
16.
Biochim Biophys Acta ; 1629(1-3): 44-52, 2003 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-14522079

RESUMEN

The SP-RING or Miz zinc finger domain that is related to the classical RING-finger motif, defines a class of proteins that can act as E3-like factors in the pathway of small ubiquitin-related modifier (SUMO) conjugation. This family includes the mammalian protein inhibitor of activated STAT (PIAS) proteins and related proteins from lower eukaryotes. Here we report the existence of a gene in Leishmania infantum, present as two identical copies placed upstream of each MAT2 gene copy, and transcribed as a single approximately 2.2 kb mRNA both in the logarithmic and stationary phases of the promastigote stage. This gene encodes a 47 kDa protein that has been named LORIEN. LORIEN is circumscribed to the cell periphery and it is antigenic during L. infantum infection of dogs and hamsters. Strikingly, this novel protein contains a highly conserved SP-RING/Miz zinc finger domain, raising the possibility that a SUMO or ubiquitin-like system may exist in this microorganism.


Asunto(s)
Genes Protozoarios , Leishmania infantum/genética , Dedos de Zinc , Secuencia de Aminoácidos , Animales , Antígenos de Protozoos/análisis , Datos de Secuencia Molecular , Proteínas Recombinantes/inmunología , Proteínas Recombinantes/metabolismo , Proteína SUMO-1/genética , Homología de Secuencia de Aminoácido , Transcripción Genética
17.
PLoS One ; 10(8): e0134414, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26274821

RESUMEN

BACKGROUND: Multiple sclerosis (MS) is a neurodegenerative, autoimmune disease of the central nervous system. Genome-wide association studies (GWAS) have identified over hundred polymorphisms with modest individual effects in MS susceptibility and they have confirmed the main individual effect of the Major Histocompatibility Complex. Additional risk loci with immunologically relevant genes were found significantly overrepresented. Nonetheless, it is accepted that most of the genetic architecture underlying susceptibility to the disease remains to be defined. Candidate association studies of the leukocyte immunoglobulin-like receptor LILRA3 gene in MS have been repeatedly reported with inconsistent results. OBJECTIVES: In an attempt to shed some light on these controversial findings, a combined analysis was performed including the previously published datasets and three newly genotyped cohorts. Both wild-type and deleted LILRA3 alleles were discriminated in a single-tube PCR amplification and the resulting products were visualized by their different electrophoretic mobilities. RESULTS AND CONCLUSION: Overall, this meta-analysis involved 3200 MS patients and 3069 matched healthy controls and it did not evidence significant association of the LILRA3 deletion [carriers of LILRA3 deletion: p = 0.25, OR (95% CI) = 1.07 (0.95-1.19)], even after stratification by gender and the HLA-DRB1*15:01 risk allele.


Asunto(s)
Eliminación de Gen , Esclerosis Múltiple/genética , Receptores Inmunológicos/genética , Epistasis Genética , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Cadenas HLA-DRB1/genética , Humanos , Población Blanca/legislación & jurisprudencia
18.
Evid. odontol. clín ; 4(1): [1-10], ene.-jun. 2018. tabs.
Artículo en Español | LILACS | ID: biblio-999798

RESUMEN

Objetivos: Analizar el estado de las prótesis totales removibles en una muestra de pacientes edéntulos bimaxilares, atendidos en la Facultad de Odontología de la Universidad de Cuenca en el periodo 2012-2015. Material y Métodos: estudio descriptivo de corte transversal, que se realizó en 70 pacientes que consultaron y recibieron tratamiento. Se realizó un análisis de los siguientes aspectos: oclusión balanceada bilateral, dimensión vertical oclusal, pérdida de dientes, fracturas, desgaste y año de realización de la prótesis, por medio de un cuestionario y un examen clínico elaborados para el estudio. Resultados: El 97,1% de pacientes presentan alguna condición afectada en su prótesis, el desgaste fue la alteración de mayor frecuencia, con 57,1%, sin embargo la oclusión balanceada bilateral correcta fue, 86%; dimensión vertical correcta, 76%; no hubo pérdida de dientes protésicos en, 90%; y ausencia de fracturas, 84%. Conclusiones: el estado protésico de los pacientes estudiados fue malo, al presentar al menos una alteración en una de sus características, de los cuales, la mayor frecuencia fueron pacientes mujeres, mayores a 45 años y con dos años de haberse realizado sus prótesis. (AU)


Objectives: To analyze the status of total removable prostheses in a sample of bimaxillary edentulous patients, attended at the Faculty of Dentistry of the University of Cuenca in the period 2012-2015. Materials and Methods: a descriptive cross-sectional study was carried out in 70 patients who consulted and received treatment. An analysis of the following aspects was performed: bilateral balanced occlusion, vertical occlusal dimension, tooth loss, fractures, wear and year of the prosthesis, by means of a questionnaire and a clinical examination prepared for the study. Results: 97.1% of patients presented some condition affected in their prosthesis, wear was the most frequent alteration, with 57.1%; however the correct bilateral balanced occlusion was 86%; correct vertical dimension, 76%; there was no loss of prosthetic teeth in, 90%; and absence of fractures, 84%. Conclusions: the prosthetic status of the patients studied was poor, showing at least one alteration in one of its characteristics, of which, the most frequent were female patients, older than 45 years and two years after having had their prosthesis. (AU)


Asunto(s)
Humanos , Dimensión Vertical , Oclusión Dental , Dentadura Completa , Epidemiología Descriptiva , Estudios Transversales , Ecuador
19.
Methods Mol Biol ; 882: 415-30, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22665248

RESUMEN

The killer-cell immunoglobulin-like receptors (KIR), which enable NK cells to detect allogeneic target cells and abnormalities in the expression of self-HLA molecules, are encoded by genes that display extensive copy number variation. These variations in the KIR genotype are relevant for multiple aspects of human health, including therapy of cancer. PCR with sequence-specific primers (SSP) is simplest and most widely used among techniques for studying KIR genotypes. Here, we present a protocol that details the critical steps of a method for KIR genotyping by PCR-SSP.


Asunto(s)
Cartilla de ADN/genética , Reacción en Cadena de la Polimerasa , Receptores KIR/genética , Genotipo , Humanos
20.
PLoS One ; 2(11): e1177, 2007 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-18000548

RESUMEN

The substantial differences between trypanosomal and leishmanial DNA topoisomerase IB concerning to their homologues in mammals have provided a new lead in the study of the structural determinants that can be effectively targeted. Leishmania donovani, the causative agent of visceral leishmaniasis, contains an unusual heterodimeric DNA topoisomerase IB. The catalytically active enzyme consists of a large subunit (LdTopIL), which contains the non-conserved N-terminal end and the phylogenetically conserved "core" domain, and of a small subunit (LdTopIS) which harbors the C-terminal region with the characteristic tyrosine residue in the active site. Heterologous co-expression of LdTopIL and LdTopIS genes in a topoisomerase I deficient yeast strain, reconstitutes a fully functional enzyme LdTopIL/S which can be used for structural studies. An approach by combinatorial cloning of deleted genes encoding for truncated versions of both subunits was used in order to find out structural insights involved in enzyme activity or protein-protein interaction. The role played by the non-conserved N-terminal extension of LdTopIL in both relaxation activity and CPT sensitivity has been examined co-expressing the full-length LdTopIS and a fully active LdTopIDeltaS deletion with several deletions of LdTopIL lacking growing sequences of the N-terminal end. The sequential deletion study shows that the first 26 amino acids placed at the N-terminal end and a variable region comprised between Ala548 to end of the C-terminal extension of LdTopIL were enzymatically dispensable. Altogether this combinatorial approach provides important structural insights of the regions involved in relaxation activity and for understanding the atypical structure of this heterodimeric enzyme.


Asunto(s)
ADN-Topoisomerasas de Tipo I/metabolismo , Leishmania donovani/enzimología , Animales , ADN-Topoisomerasas de Tipo I/química , ADN-Topoisomerasas de Tipo I/genética , Dimerización , Leishmania donovani/química , Conformación Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
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