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1.
Proc Natl Acad Sci U S A ; 120(7): e2220475120, 2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-36745785

RESUMO

Chromatin modifications play a fundamental role in controlling transcription and genome stability and yet despite their importance, are poorly understood in early-diverging fungi. We present a comprehensive study of histone lysine and DNA methyltransferases across the Mucoromycota, emphasizing heterochromatin formation pathways that rely on the Clr4 complex involved in H3K9-methylation, the Polycomb-repressive complex 2 driving H3K27-methylation, or DNMT1-like methyltransferases that catalyze 5mC DNA methylation. Our analysis uncovered H3K9-methylated heterochromatin as the major chromatin modification repressing transcription in these fungi, which lack both Polycomb silencing and cytosine methylation. Although small RNAs generated by RNA interference (RNAi) pathways facilitate the formation of heterochromatin in many eukaryotic organisms, we show that RNAi is not required to maintain either genomic or centromeric heterochromatin in Mucor. H3K9-methylation and RNAi act independently to control centromeric regions, suggesting a functional subspecialization. Whereas the H3K9 methyltransferase Clr4 and heterochromatin formation are essential for cell viability, RNAi is dispensable for viability yet acts as the main epigenetic, regulatory force repressing transposition of centromeric GremLINE1 elements. Mutations inactivating canonical RNAi lead to rampant transposition and insertional inactivation of targets resulting in antimicrobial drug resistance. This fine-tuned, Rdrp2-dependent RNAi activity is critical for genome stability, restricting GremLINE1 retroelements to the centromeres where they occupy long heterochromatic islands. Taken together, our results suggest that RNAi and heterochromatin formation are independent genome defense and regulatory mechanisms in the Mucorales, contributing to a paradigm shift from the cotranscriptional gene silencing observed in fission yeasts to models in which heterochromatin and RNAi operate independently in early-diverging fungi.


Assuntos
Instabilidade Genômica , Heterocromatina , Mucorales , Proteínas de Ciclo Celular/metabolismo , Cromatina/metabolismo , Metilação de DNA , Heterocromatina/genética , Heterocromatina/metabolismo , Histona-Lisina N-Metiltransferase/metabolismo , Mucorales/genética , Mucorales/metabolismo , Interferência de RNA
2.
J Infect Dis ; 229(6): 1791-1795, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38134382

RESUMO

Vaginal inserts that can be used on demand before or after sex may be a desirable human immunodeficiency virus (HIV) prevention option for women. We recently showed that inserts containing tenofovir alafenamide fumarate (TAF, 20 mg) and elvitegravir (EVG, 16 mg) were highly protective against repeated simian/human immunodeficiency virus (SHIV) vaginal exposures when administered to macaques 4 hours before or after virus exposure (93% and 100%, respectively). Here, we show in the same macaque model that insert application 8 hours or 24 hours after exposure maintains high efficacy (94.4% and 77.2%, respectively). These data extend the protective window by TAF/EVG inserts and inform their clinical development for on-demand prophylaxis in women.


Assuntos
Adenina , Alanina , Fármacos Anti-HIV , Quinolonas , Síndrome de Imunodeficiência Adquirida dos Símios , Tenofovir , Animais , Tenofovir/administração & dosagem , Tenofovir/análogos & derivados , Feminino , Quinolonas/administração & dosagem , Quinolonas/farmacologia , Alanina/administração & dosagem , Síndrome de Imunodeficiência Adquirida dos Símios/prevenção & controle , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Fármacos Anti-HIV/administração & dosagem , Adenina/análogos & derivados , Adenina/administração & dosagem , Adenina/farmacologia , Adenina/uso terapêutico , Vagina/virologia , Vagina/efeitos dos fármacos , Vírus da Imunodeficiência Símia/efeitos dos fármacos , Infecções por HIV/prevenção & controle , Infecções por HIV/virologia , Administração Intravaginal , Macaca mulatta , Modelos Animais de Doenças
3.
Clin Infect Dis ; 78(1): 80-89, 2024 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-37540989

RESUMO

BACKGROUND: Powassan virus (POWV) is an emerging arthropod-borne flavivirus, transmitted by Ixodes spp. ticks, which has been associated with neuroinvasive disease and poor outcomes. METHODS: A retrospective study was conducted at Mayo Clinic from 2013 to 2022. We included clinical and epidemiologic data of probable and confirmed neuroinvasive POWV cases. RESULTS: Sixteen patients with neuroinvasive POWV were identified; their median age was 63.2 years, and 62.5% were male. Six patients presented with rhombencephalitis, 4 with isolated meningitis, 3 with meningoencephalitis, 2 with meningoencephalomyelitis, and 1 with opsoclonus myoclonus syndrome. A median time of 18 days was observed between symptom onset and diagnosis. Cerebrospinal fluid analysis showed lymphocytic pleocytosis with elevated protein and normal glucose in the majority of patients. Death occurred within 90 days in 3 patients (18.8%), and residual neurologic deficits were seen in 8 survivors (72.7%). CONCLUSIONS: To our knowledge, this is the largest case series of patients with neuroinvasive POWV infection. We highlight the importance of a high clinical suspicion among patients who live in or travel to high-risk areas during the spring to fall months. Our data show high morbidity and mortality rates among patients with neuroinvasive disease.


Assuntos
Vírus da Encefalite Transmitidos por Carrapatos , Encefalite Transmitida por Carrapatos , Ixodes , Meningoencefalite , Animais , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Estudos Retrospectivos , Encefalite Transmitida por Carrapatos/diagnóstico , Encefalite Transmitida por Carrapatos/epidemiologia
4.
J Clin Microbiol ; 62(3): e0153723, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38349145

RESUMO

Rhodococcus equi is an opportunistic pathogen known to cause pulmonary and extrapulmonary disease among immunocompromised patients. Treatment is frequently challenging due to intrinsic resistance to multiple antibiotic classes. While non-equi Rhodococcus spp. are prevalent, their clinical significance is poorly defined. There is also limited data on antibiotic susceptibility testing (AST) of Rhodococcus infection in humans. We conducted a single-center, retrospective cohort study evaluating clinical characteristics, microbiologic profile, and AST of Rhodococcus infections between June 2012 and 2022 at our tertiary academic medical center. Identification of Rhodococcus spp. was performed by Sanger 16S rRNA gene sequencing and/or matrix-assisted laser desorption ionization-time of flight mass spectrometry, and AST was performed by agar dilution. Three hundred twenty-two isolates of Rhodococcus spp. were identified from blood (50%), pulmonary (26%), and bone/joint (12%) sources. R. equi/hoagii, R. corynebacterioides, and R. erythropolis were the most frequently isolated species, with 19% of isolates identified only to genus level. One hundred ninety-nine isolates evaluated for AST demonstrated high-level resistance to amoxicillin/clavulanate, cephalosporins, and aminoglycosides. More than 95% susceptibility to imipenem, vancomycin, linezolid, rifampin, and clarithromycin was observed. Non-equi species showed a significantly more favorable AST profile relative to R. equi. Clinically significant Rhodococcus infection was rare with 10 cases diagnosed (majority due to R. equi) and managed. The majority of patients received 2- or 3-drug combination therapy for 2-6 months, with favorable clinical response. Significant differences in AST were observed between R. equi and non-equi species. Despite high antimicrobial resistance to several antibiotic classes, imipenem and vancomycin remain appropriate empiric treatment options for R. equi. Future research evaluating mechanisms underlying antimicrobial resistance is warranted.


Assuntos
Infecções por Actinomycetales , Rhodococcus equi , Rhodococcus , Humanos , Rhodococcus/genética , Vancomicina/uso terapêutico , Estudos Retrospectivos , RNA Ribossômico 16S , Infecções por Actinomycetales/tratamento farmacológico , Antibacterianos/uso terapêutico , Rhodococcus equi/genética , Imipenem/uso terapêutico
5.
Reprod Biomed Online ; 48(1): 103570, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37952277

RESUMO

The Association for the Study of Reproductive Biology (ASEBIR) Interest Group in Embryology (in Spanish 'Grupo de Interés de Embriología') reviewed key morphokinetic parameters to assess the contribution of time-lapse technology (TLT) to the ASEBIR grading system. Embryo grading based on morphological characteristics is the most widely used method in human assisted reproduction laboratories. The introduction and implementation of TLT has provided a large amount of information that can be used as a complementary tool for morphological embryo evaluation and selection. As part of IVF treatments, embryologists grade embryos to decide which embryos to transfer or freeze. At the present, the embryo grading system developed by ASEBIR does not consider dynamic events observed through TLT. Laboratories that are using TLT consider those parameters as complementary data for embryo selection. The aim of this review was to evaluate review time-specific morphological changes during embryo development that are not included in the ASEBIR scoring system, and to consider them as candidates to add to the scoring system.


Assuntos
Embrião de Mamíferos , Desenvolvimento Embrionário , Humanos , Imagem com Lapso de Tempo/métodos , Transferência Embrionária/métodos , Biologia , Técnicas de Cultura Embrionária , Implantação do Embrião , Fertilização in vitro/métodos , Blastocisto
6.
J Toxicol Environ Health A ; 87(7): 275-293, 2024 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-38285019

RESUMO

Tithonia diversifolia is a perennial bushy plant found in South America with significant ethnopharmacological importance as an antimalarial, antidiabetic, antibacterial, and anticancer agent. The aim of the present study was to determine the cytotoxicity of the ethanolic extract from leaves of T. diversifolia (TdE) on human cancer cell lines (HCT-116, SNB-19, NCIH-460 and MCF-7), as well as the mechanism of action involved in cell death and cellular modulation of oxidative stress. The TdE exhibited significant activity with IC50 values ranging from 7.12 to 38.41 µg/ml, with HCT-116 being the most sensitive cell line. Subsequent experiments were conducted with HCT-116 cell line. TdE decreased the number of viable cells, followed by induction of apoptotic events, increase in mitochondrial membrane permeabilization, and enhanced G2/M phase of the cell cycle. Pro-oxidative effects including elevated acidic vesicular organelle formation, lipid peroxidation, and nitric oxide by-products, as well as reduced levels of intracellular glutathione and reactive oxygen species production were also observed following incubation with TdE, which may lead to DNA damage followed by apoptotic cell death. These results demonstrate the potential of TdE ethanolic leaf extraction for biological activity and enhance the importance of continuing to study natural sources of plants for the development of anticancer agents.


Assuntos
Antineoplásicos , Tithonia , Humanos , Extratos Vegetais/farmacologia , Células HCT116 , Estresse Oxidativo , Apoptose , Espécies Reativas de Oxigênio/metabolismo , Etanol , Antineoplásicos/farmacologia , Folhas de Planta
7.
J Obstet Gynaecol Res ; 50(7): 1268-1272, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38720638

RESUMO

Pregnancy-associated atypical hemolytic uremic syndrome (P-aHUS) is a rare disease. There are only few reports in the literature, and most are in the puerperium period. It is a thrombotic microangiopathy (TMA) characterized for microangiopathic hemolytic anemia, thrombocytopenia, and renal dysfunction. We report the case of a pregnant patient at 26.3 gestation weeks, who developed clinical features of TMA, neurological alterations, and septic shock; then after fetus and placental delivery, no clinical improvement was observed; a diagnostic protocol was performed due to suspicion of P-aHUS, showing improvement after the plasma exchange sessions and eculizumab. We present here a brief review of the case since it is an entity that needs to be suspected during pregnancy when TMA features and requires an immediate diagnosis to provide timely treatment.


Assuntos
Síndrome Hemolítico-Urêmica Atípica , Humanos , Feminino , Gravidez , Síndrome Hemolítico-Urêmica Atípica/terapia , Síndrome Hemolítico-Urêmica Atípica/diagnóstico , Adulto , Troca Plasmática , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/administração & dosagem , Complicações Hematológicas na Gravidez/terapia , Complicações Hematológicas na Gravidez/diagnóstico
8.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-38218430

RESUMO

It is widely acknowledged that inflammatory bowel disease (IBD) is associated with a high prevalence of sexual dysfunction (SD). However, there is a notable paucity of specific literature in this field. This lack of information impacts various aspects, including the understanding and comprehensive care of SD in the context of IBD. Furthermore, patients themselves express a lack of necessary attention in this area within the treatment of their disease, thus creating an unmet need in terms of their well-being. The aim of this position statement by the Spanish Working Group on Crohn's Disease and Ulcerative Colitis (GETECCU) is to provide a review on the most relevant aspects and potential areas of improvement in the detection, assessment, and management of SD in patients with IBD and to integrate the approach to sexual health into our clinical practice. Recommendations are established based on available scientific evidence and expert opinion. The development of these recommendations by GETECCU has been carried out through a collaborative multidisciplinary approach involving gastroenterologists, gynecologists, urologists, surgeons, nurses, psychologists, sexologists, and, of course, patients with IBD.

9.
Gynecol Oncol ; 177: 150-156, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37696217

RESUMO

OBJECTIVE: The PORTEC-2 update suggested that substantial lymphovascular space invasion (LVSI) and abnormal p53 expression (p53abnl) predict for poorer outcomes and that these patients should be treated with external beam radiation therapy (EBRT). We aim to determine if patients with these risk factors who undergo a lymph node (LN) assessment show similar outcomes. METHODS: We retrospectively reviewed 126 patients with FIGO 2009 stage IA grade 3, stage IB grade 1-2, and stage IIIC (positive LN but no other stage II/III risk factors) endometrioid endometrial cancer who underwent LN assessment. Local (LR), regional recurrences (RR), and distant metastases were analyzed using competing risk methods, and overall survival (OS) was analyzed using Kaplan-Meier. RESULTS: Median follow-up time was 37.2 months. OS was significantly different between patients with and without p53abnl expression (16.7% versus 3.1% deceased), and between patients with and without LVSI (11.1% versus 1.5% deceased; p < 0.01 for both). The 2-year cumulative incidence of LR for patients with p53abnl versus wild type p53 and LVSI versus no LVSI was 11.1% (95% CI 0-25.6) versus 2.2% (95% CI 0-5.25; p = 0.04), and 11.4% (95% CI 2.0-20.9) versus 0%, respectively (p < 0.01). The 2-year cumulative RR in patients with LVSI versus no LVSI was 6.9% (95% CI 0-14.4) versus 0% (p = 0.05). No patients who completed pelvic RT experienced an in-field recurrence. CONCLUSIONS: Despite LN assessment, patients with high-intermediate risk early-stage or stage IIIC (with positive lymph nodes only but no other stage II or III risk factors) endometrial cancer with p53abnl expression and/or LVSI have worse outcomes. These patients may derive benefit from intensification with EBRT to improve local and pelvic control.

10.
Gynecol Oncol ; 174: 42-48, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37149904

RESUMO

OBJECTIVES: Emerging data suggests that abnormal (nuclear) ß-catenin expression in some settings is associated with poorer outcomes. Our study aimed to verify the significance of abnormal ß-catenin expression in early-stage endometrial cancer patients and determine if adjuvant radiation therapy (RT) improves local control. METHODS: We identified 213 patients with FIGO 2018 stage I-II endometrioid endometrial cancer who underwent surgery from 2009 to 2021 with ß-catenin expression assessed. Vaginal, regional, and distant recurrences were analyzed using competing risk methods, and overall survival was analyzed using Kaplan-Meier. RESULTS: Median follow up was 53.2 months; 6.9% experienced vaginal, 8.2% regional, and 7.4% distant recurrence. For the entire cohort, abnormal ß-catenin expression was significantly associated with vaginal recurrence and remained significant on multivariate analysis (p = 0.03). There were 114 patients in the no specific molecular profile (NSMP) subgroup, and abnormal ß-catenin expression was present in 46.5%. In the NSMP subgroup, abnormal ß-catenin expression was associated with increased rates of vaginal recurrence (p = 0.06). Abnormal ß-catenin expression in the NSMP subgroup was significant on multivariate analysis for vaginal recurrence (p = 0.04). RT significantly decreased vaginal recurrences in the entire cohort in patients with abnormal ß-catenin expression (0%) versus wild type expression (17.5%; p = 0.03). In the NSMP subgroup 0% of patients who received RT versus 20.9% of patients who did not receive RT experienced a vaginal recurrence (p = 0.03). CONCLUSION: Use of adjuvant RT for stage I-II NSMP endometrial cancer with abnormal ß-catenin expression improved local control. RT should be considered in these patients to decrease risk of vaginal recurrences.


Assuntos
Neoplasias do Endométrio , beta Catenina , Feminino , Humanos , Radioterapia Adjuvante/métodos , Estadiamento de Neoplasias , Histerectomia , Neoplasias do Endométrio/radioterapia , Neoplasias do Endométrio/cirurgia , Recidiva , Recidiva Local de Neoplasia/patologia , Estudos Retrospectivos
11.
Transpl Infect Dis ; 25 Suppl 1: e14127, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37594211

RESUMO

BACKGROUND: The incidence of mycobacterial infections in patients with hematologic malignancies and hematopoietic stem cell transplant (HSCT) recipients is increasing, contributing to significant mortality and morbidity. This review explores the epidemiology, risk factors, clinical presentation, diagnosis, and treatment of nontuberculous mycobacteria (NTM) in this population. METHODS: A literature search was performed using PubMed with keywords and MeSH terms pertaining to the topics of nontuberculous mycobacteria, hematologic malignancies, hematopoietic stem cell transplant, cellular therapies, chimeric antigen therapies, epidemiology, diagnosis, and treatment. Additionally, we examined the reference lists of the included articles to identify other pertinent studies. RESULTS: Diagnosing mycobacterial disease among patients with hematologic disease and treatment-associated immunosuppressive conditions is challenging due to the lack of distinctive clinical, radiographic, and laboratory markers, as well as the atypical manifestations compared to immunocompetent patients. Treatment involves using a combination of antibiotics for extended durations, coupled with strategies to achieve source control and reduce immunosuppression when feasible. This is complicated by the absence of clear data correlating in-vitro drug susceptibility and clinical outcome for many antimicrobials use to treat NTM, adverse drug-drug interactions, and the frequent challenges related to poor medication tolerability and toxicities. CONCLUSION: The rising incidence and corresponding clinical challenges of mycobacterial infections in this unique patient population necessitate a heightened awareness and familiarity of NTM disease by clinicians to achieve timely diagnosis and favorable treatment outcomes.


Assuntos
Neoplasias Hematológicas , Transplante de Células-Tronco Hematopoéticas , Infecções por Mycobacterium não Tuberculosas , Humanos , Infecções por Mycobacterium não Tuberculosas/tratamento farmacológico , Infecções por Mycobacterium não Tuberculosas/epidemiologia , Infecções por Mycobacterium não Tuberculosas/etiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Micobactérias não Tuberculosas , Imunossupressores/efeitos adversos , Neoplasias Hematológicas/complicações , Neoplasias Hematológicas/terapia
12.
Transpl Infect Dis ; 25(2): e14050, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36852753

RESUMO

BACKGROUND: Current guidelines recommend immunomodulators, tocilizumab or baricitinib, for the management of severe coronavirus disease-2019 (COVID-19) in patients with increasing oxygen requirements. Given their immunosuppressive effects, there is a concern for higher rates of infection among transplant recipients. METHODS: A retrospective cohort study of transplant patients with severe COVID-19 between April 2020 and January 2022 was performed at the Mayo Clinic. The primary outcome was incidence of secondary infections after COVID-19 diagnosis. Secondary outcomes were 90-day mortality, ventilatory days, and thromboembolic events. RESULTS: A total of 191 hospitalized transplant patients were studied, including 77 (40.3%) patients who received an immunomodulator. Overall, 89% were solid organ transplant recipients, with kidney as the most common transplanted organ (50.3%). The majority (89.0%) required oxygen supplementation on admission, and 39.8% of these patients required mechanical ventilation during the hospital course. There was no significant difference in the incidence of secondary infections between those who received or did not receive an immunomodulator (p = .984). Likewise, there was no difference in 90-day mortality between patients who received or did not receive an immunomodulator (p = .134). However, higher mortality was observed among patients that developed a secondary infection (p < .001). CONCLUSION: The use of immunomodulators in transplant patients with severe COVID-19 was not significantly associated with an increased risk of secondary infections. Secondary infections were associated with higher risk of all-cause mortality. Future studies of larger cohorts are needed to explore the effect of immunomodulators on survival among transplant patients with COVID-19.


Assuntos
COVID-19 , Coinfecção , Humanos , COVID-19/epidemiologia , SARS-CoV-2 , Estudos Retrospectivos , Teste para COVID-19 , Fatores Imunológicos/uso terapêutico , Adjuvantes Imunológicos , Transplantados
13.
Transpl Infect Dis ; 25(1): e13998, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36477946

RESUMO

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has been raging since the end of 2019 and has shown worse outcomes in solid organ transplant (SOT) recipients. The clinical differences as well as outcomes between respiratory viruses have not been well defined in this population. METHODS: This is a retrospective cohort study of adult SOT recipients with nasopharyngeal swab or bronchoalveolar lavage PCR positive for either SARS-CoV-2, seasonal coronavirus, respiratory syncytial virus (RSV) or influenza virus from January 2017 to October 2020. The follow up period was 3 months. Clinical characteristics and outcomes were evaluated. RESULTS: A total of 377 recipients including 157 SARS-CoV-2, 70 seasonal coronavirus, 50 RSV and 100 influenza infections were identified. The most common transplanted organ was kidney 224/377 (59.4%). Lower respiratory tract infection (LRTI) was found in 210/377 (55.7%) and the risk factors identified with multivariable analysis were SARS-CoV-2 infection, steroid use, and older age. Co- and secondary infections were seen in 77/377 (20.4%) recipients with bacterial pathogens as dominant. Hospital admission was seen in 266/377 (67.7%) recipients without significant statistical difference among viruses, however, ICU admission, mechanical ventilation and mortality were higher with SARS-CoV-2 infection. In the multivariable model, the risk factors for mortality were SARS-CoV-2 infection and older age. CONCLUSIONS: We found higher incidence of ICU admission, mechanical ventilation, and mortality among SARS-CoV-2 infected recipients. Older age was found to be the risk factor for lower respiratory tract infection and mortality for SARS-CoV-2, coronaviruses, RSV and influenza virus groups.


Assuntos
COVID-19 , Influenza Humana , Transplante de Órgãos , Infecções por Vírus Respiratório Sincicial , Infecções Respiratórias , Adulto , Humanos , SARS-CoV-2 , Influenza Humana/etiologia , Estudos Retrospectivos , Estações do Ano , Transplante de Órgãos/efeitos adversos , Vírus Sinciciais Respiratórios , Transplantados
14.
Biometals ; 36(4): 887-902, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36658453

RESUMO

Mangrove forests are threatened by the continuous discharge of inorganic pollutants and studies show that coasts receive high levels of heavy metals, from which lead (Pb) is one of the most persistent and toxic. In the present study, lead accumulation capacity, as well as its toxicological effects and tolerance mechanisms, such as proline accumulation and increased antioxidant capacity were evaluated in two contrasting mangrove species: Avicennia germinans and Laguncularia racemosa. Six-month-old plants were exposed to different concentrations of lead nitrate (0, 75, 150, and 300 µM) and samples of roots and leaves were taken from all treatments at different times during a 30d exposure period. Both species accumulated Pb in their tissues mainly in the roots, but L. racemosa had a greater capacity to accumulate Pb than A. germinans. Nevertheless, lead exposure caused less leaf chlorosis, lower reduction in the efficiency of photosystem II, lower reduction of daily photosynthetic rates, and lower electrolyte leakage in L. racemosa than in A. germinans. In line with those results, L. racemosa, in response to Pb exposure, accumulated more proline and showed higher antioxidant capacity than A. germinans, in both roots and leaves. Altogether, L. racemosa might be more suitable for restoration purposes, as it is not only capable of accumulating more Pb in its tissues but also shows greater tolerance to the stress caused by lead.


Assuntos
Combretaceae , Metais Pesados , Antioxidantes , Chumbo/toxicidade , Folhas de Planta , Fotossíntese , Combretaceae/fisiologia
15.
PLoS Genet ; 16(7): e1008611, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32658892

RESUMO

Epimutations in fungal pathogens are emerging as novel phenomena that could explain the fast-developing resistance to antifungal drugs and other stresses. These epimutations are generated by RNA interference (RNAi) mechanisms that transiently silence specific genes to overcome stressful stimuli. The early-diverging fungus Mucor circinelloides exercises a fine control over two interacting RNAi pathways to produce epimutants: the canonical RNAi pathway and a new RNAi degradative pathway. The latter is considered a non-canonical RNAi pathway (NCRIP) because it relies on RNA-dependent RNA polymerases (RdRPs) and a novel ribonuclease III-like named R3B2 to degrade target transcripts. Here in this work, we uncovered the role of NCRIP in regulating virulence processes and transposon movements through key components of the pathway, RdRP1 and R3B2. Mutants in these genes are unable to launch a proper virulence response to macrophage phagocytosis, resulting in a decreased virulence potential. The transcriptomic profile of rdrp1Δ and r3b2Δ mutants revealed a pre-exposure adaptation to the stressful phagosomal environment even when the strains are not confronted by macrophages. These results suggest that NCRIP represses key targets during regular growth and releases its control when a stressful environment challenges the fungus. NCRIP interacts with the RNAi canonical core to protect genome stability by controlling the expression of centromeric retrotransposable elements. In the absence of NCRIP, these retrotransposons are robustly repressed by the canonical RNAi machinery; thus, supporting the antagonistic role of NCRIP in containing the epimutational pathway. Both interacting RNAi pathways might be essential to govern host-pathogen interactions through transient adaptations, contributing to the unique traits of the emerging infection mucormycosis.


Assuntos
Mucorales/genética , Mucormicose/genética , Interferência de RNA , Ribonuclease III/genética , Antifúngicos/farmacologia , Farmacorresistência Fúngica/genética , Epigênese Genética/genética , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica/genética , Instabilidade Genômica/efeitos dos fármacos , Interações Hospedeiro-Patógeno/genética , Mucorales/patogenicidade , Mucormicose/microbiologia , Mutação/genética , RNA Mensageiro/genética , Transdução de Sinais/efeitos dos fármacos , Virulência/genética
16.
Parasitol Res ; 122(5): 1087-1105, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36913025

RESUMO

Different mechanisms of the host immune response against the primary amebic meningoencephalitis (PAM) in the mouse protection model have been described. It has been proposed that antibodies opsonize Naegleria fowleri trophozoites; subsequently, the polymorphonuclear cells (PMNs) surround the trophozoites to avoid the infection. FcγRs activate signaling pathways of adapter proteins such as Syk and Hck on PMNs to promote different effector cell functions which are induced by the Fc portion of the antibody-antigen complexes. In this work, we analyzed the activation of PMNs, epithelial cells, and nasal passage cells via the expression of Syk and Hck genes. Our results showed an increment of the FcγRIII and IgG subclasses in the nasal cavity from immunized mice as well as Syk and Hck expression was increased, whereas in the in vitro assay, we observed that when the trophozoites of N. fowleri were opsonized with IgG anti-N. fowleri and interacted with PMN, the expression of Syk and Hck was also increased. We suggest that PMNs are activated via their FcγRIII, which leads to the elimination of the trophozoites in vitro, while in the nasal cavity, the adhesion and consequently infection are avoided.


Assuntos
Amebíase , Meningoencefalite , Naegleria fowleri , Receptores de IgG , Animais , Camundongos , Amebíase/parasitologia , Infecções Protozoárias do Sistema Nervoso Central , Imunoglobulina G , Meningoencefalite/parasitologia , Camundongos Endogâmicos BALB C , Cavidade Nasal , Receptores de IgG/metabolismo
17.
Rev Panam Salud Publica ; 47: e95, 2023.
Artigo em Espanhol | MEDLINE | ID: mdl-38089107

RESUMO

Objective: Establish the disease burden of malignant mesothelioma (MM) in Colombia between 2015 and 2020, and its association with the subnational sociodemographic development index (SDI) and with asbestos sites. Methods: Mixed ecological study of the Colombian population diagnosed with MM (according to ICD-10) from 2015 to 2020. The global burden of disease (GBD) was estimated using the methodology proposed by Murray and Lopez, based on prevalence and mortality data obtained from official sources. The subnational (departmental level) SDI was estimated as a measure of socioeconomic development. Linear regressions were established with the GBD, SDI, and documented asbestos sites. Results: The estimated GBD of MM in Colombia during 2015-2020 was 51.71 disability-adjusted life years (DALYs) per 1 000 000 inhabitants (15 375.79 total DALYs), with predominance in people over 50 years of age (91.1%) and males (66.4%).Bogotá and Valle del Cauca were the departments with the highest number of adjusted DALYs. Bogotá had the highest SDI and Guainía and Cesar had the lowest. There was evidence of an association between DALYs and SDI, explaining 22.8% of DALYs. Conclusion: Malignant mesothelioma is the cause of a large number of DALYs, predominantly in the departments with greater socioeconomic development and with companies that used to use asbestos. However, possible underdiagnosis of MM limits analysis of the information.


Objetivo: Estabelecer o ônus da doença por mesotelioma maligno (MM) na Colômbia entre 2015 e 2020 e sua associação ao índice sociodemográfico subnacional (ISS) e locais de amianto. Métodos: Estudo ecológico misto na população colombiana diagnosticada com MM, de acordo com a CID-10 durante 2015 a 2020. A carga global da doença (CGD) foi estimada usando a metodologia proposta por Murray e López com base na prevalência e na mortalidade obtidas de fontes oficiais. O SDI subnacional (nível departamental) foi estimado como uma medida de desenvolvimento socioeconômico e foram estabelecidas regressões lineares com CGD, SDI e localizações documentadas de amianto. Resultados: A estimativa de CGD por MM na Colômbia entre 2015-2020 foi de 51,71 anos de vida ajustados por incapacidade (AVAI) por 1 000 000 de habitantes (15 375,79 AVAI totais), com predominância em pessoas com mais de 50 anos (91,1%) e do sexo masculino (66,4%).Com relação aos departamentos, Bogotá e Valle del Cauca tiveram o maior número de AVAI ajustados, enquanto Bogotá teve o maior SDI, e Guainía e Cesar, o menor. Houve uma associação entre os AVAI e o SDI, sendo que o SDI foi responsável por 22,8% dos AVAI. Conclusões: O MM é a causa de um grande número de AVAI, predominantemente em departamentos com maior desenvolvimento socioeconômico e com a presença de empresas que usavam amianto; no entanto, o possível subdiagnóstico do MM limita a análise das informações.

19.
J Virol ; 95(20): e0116521, 2021 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-34319156

RESUMO

Ebola virus (EBOV) attaches to target cells using two categories of cell surface receptors: C-type lectins and phosphatidylserine (PS) receptors. PS receptors typically bind to apoptotic cell membrane PS and orchestrate the uptake and clearance of apoptotic debris. Many enveloped viruses also contain exposed PS and can therefore exploit these receptors for cell entry. Viral infection can induce PS externalization in host cells, resulting in increased outer PS levels on budding virions. Scramblase enzymes carry out cellular PS externalization; thus, we targeted these proteins in order to manipulate viral envelope PS levels. We investigated two scramblases previously identified to be involved in EBOV PS levels, transmembrane protein 16F and Xk-related protein 8 (XKR8), as possible mediators of cellular and viral envelope surface PS levels during the replication of recombinant vesicular stomatitis virus containing its native glycoprotein (rVSV/G) or the EBOV glycoprotein (rVSV/EBOV-GP). We found that rVSV/G and rVSV/EBOV-GP virions produced in XKR8 knockout cells contain decreased levels of PS on their surfaces, and the PS-deficient rVSV/EBOV-GP virions are 70% less efficient at infecting cells through PS receptors. We also observed reduced rVSV and EBOV virus-like particle (VLP) budding in ΔXKR8 cells. Deletion of XKR8 in HAP1 cells reduced rVSV/G and rVSV/EBOV-GP budding by 60 and 65%, respectively, and reduced Ebola VLP budding more than 60%. We further demonstrated that caspase cleavage of XKR8 is required to promote budding. This suggests that XKR8, in addition to mediating virion PS levels, may also be critical for enveloped virus budding at the plasma membrane. IMPORTANCE Within the last decade, countries in western and central Africa have experienced the most widespread and deadly Ebola outbreaks since Ebola virus was identified in 1976. While outbreaks are primarily attributed to zoonotic transfer events, new evidence is emerging outbreaks may be caused by a combination of spillover events and viral latency or persistence in survivors. The possibility that Ebola virus can remain dormant and then reemerge in survivors highlights the critical need to prevent the virus from entering and establishing infection in human cells. Thus far, host cell scramblases TMEM16F and XKR8 have been implicated in Ebola envelope surface phosphatidylserine (PS) and cell entry using PS receptors. We assessed the contributions of these proteins using CRISPR knockout cells and two EBOV models: rVSV/EBOV-GP and EBOV VLPs. We observed that XKR8 is required for optimal EBOV envelope PS levels and infectivity and particle budding across all viral models.


Assuntos
Ebolavirus/metabolismo , Fosfatidilserinas/metabolismo , Liberação de Vírus/fisiologia , Linhagem Celular , Ebolavirus/patogenicidade , Glicoproteínas/metabolismo , Doença pelo Vírus Ebola/virologia , Humanos , Fosfatidilserinas/fisiologia , Proteínas de Transferência de Fosfolipídeos/metabolismo , Proteínas de Transferência de Fosfolipídeos/fisiologia , Proteínas do Envelope Viral/metabolismo , Vírion/metabolismo , Montagem de Vírus/genética , Montagem de Vírus/fisiologia , Liberação de Vírus/genética
20.
Sex Transm Dis ; 49(3): 197-203, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-34670941

RESUMO

BACKGROUND: Human immunodeficiency virus (HIV) partner services are an essential component of comprehensive HIV prevention and care. We examined factors associated with partner notification, HIV testing, and HIV positivity among partners of HIV-diagnosed persons (index persons) contacted by Centers for Disease Control and Prevention (CDC)-funded state and local health departments. METHODS: We analyzed partner service data submitted to the CDC by 61 state and local health departments from 2013 to 2017. Using multivariate Poisson regression-adjusted for clustering effects among partners reported by a common index person-we assessed associations between 3 outcomes of interest (partner notification, HIV testing, and HIV positivity) and the demographic characteristics, risk behaviors, geographic region, and service year of index persons and their partners. RESULTS: A total of 51,368 sexual and/or needle-sharing partners were matched with 33,524 index persons. Of notifiable partners, 97.2% were notified of their potential HIV exposure, and 52.3% were tested for HIV. Among 21,842 notified and tested partners, 23.8% were newly diagnosed with an HIV infection. Partner notification, HIV testing, and HIV positivity were associated with both partner and index person characteristics (individually and interactively), geographic region, and year of service. CONCLUSIONS: Partner service programs provided through CDC-funded health departments were effective in both partner notification and identification of undiagnosed HIV infection among partners. However, HIV testing rate among notified partners remained low. Implementing strategies to address gaps in HIV testing can contribute toward ending the HIV epidemic in the United States.


Assuntos
Infecções por HIV , Soropositividade para HIV , Busca de Comunicante , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Soropositividade para HIV/epidemiologia , Humanos , Comportamento Sexual , Parceiros Sexuais , Estados Unidos/epidemiologia
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