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INTRODUCTION: There is limited literature on digital ischemia in systemic Lupus erythematosus (SLE). We report the prevalence, associations and outcome of digital infarcts and gangrene from the Indian SLE inception cohort (INSPIRE). METHODS: From the web-based database of INSPIRE, we extracted information for patients with 'Digital Infarct' and 'Digital gangrene' at enrolment into cohort, together considered as critical peripheral ischemia (CPI); all others were controls. We describe the associations of CPI with SLE clinical phenotype, autoantibodies, and disease activity at enrolment. We also report short term outcomes viz. Digital tissue loss and early mortality up to 6 months and recurrence of digital ischemic events in cases till date. RESULTS: Of 2503 SLE patients enrolled into the INSPIRE cohort, we identified 75 (2.9%) patients with CPI, 72 (96%) women and 6 (8%) children. Of them, 55 (73.3%) had digital gangrene and 21 (28%) patients had digital infarcts. Majority of digital gangrene resulted in amputation distal to terminal phalanx (63.6%). Multivariable analysis showed that pulmonary hypertension AOR [6.34 (1.99, 20.2)], coexistent thrombosis AOR [27.8 (15.7, 48.7)], triple antiphospholipid antibody positivity AOR [5.36 (1.67, 16.9)] and the presence of anti-Scl-70-antibody AOR [5.59 (1.86, 16.7)] were more likely while patients with class 3 or 4 lupus nephritis AOR [0.37 (0.15, 0.95)] and anti-nucleosome antibodies AOR [0.47 (0.23, 0.99)] were less likely to be associated with CPI. SLEDAI and short-term mortality were similar between cases and controls. CONCLUSIONS: CPI occurred in a higher proportion (2.9%) of SLE patients in the INSPIRE cohort as compared to earlier reports. Both prothrombotic state and vasculopathy contribute to its occurrence.
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Dedos , Gangrena , Isquemia , Lupus Eritematoso Sistémico , Humanos , Lupus Eritematoso Sistémico/complicaciones , Lupus Eritematoso Sistémico/epidemiología , Femenino , Masculino , Isquemia/epidemiología , Adulto , India/epidemiología , Prevalencia , Gangrena/epidemiología , Gangrena/etiología , Dedos/irrigación sanguínea , Dedos/patología , Persona de Mediana Edad , Adulto Joven , Niño , Amputación Quirúrgica/estadística & datos numéricos , Estudios de Cohortes , Adolescente , Análisis Multivariante , Factores de RiesgoRESUMEN
Antiphospholipid antibodies (APLA) are present in one-third of systemic lupus erythematosus (SLE) patients, and they are associated with both criteria and non-criteria manifestations. We studied the prevalence, clinical associations, and impact on mortality of APLA in SLE patients from India. Among the Indian SLE inception cohort (INSPIRE), patients who had data on all five routinely performed APLAs [lupus anticoagulant (LA), IgG and IgM anticardiolipin antibody (aCL) and anti-ß2-glycoprotein I(ß2GPI)] at enrolment were selected. Patients were divided into four categories based on the presence/absence of APLA associated manifestations and presence/absence of the APLA viz SLE-APS, SLE-APLA, SLE: events but no APLA, and SLE: no events, no APLA (reference group). 1035 SLE patients at least 1 APLA antibody was detected in 372 (35.9%). LA was present in 206 (19.9%), aCL in 126 (12.2%) and ß2-GPI in 178 (17.2%). There were 88 thrombotic events in 83 patients (8.0%); 73 (82.9%) being arterial; APLA positivity was present in 37 (44.6%) [AOR 1.70 (1.054, 2.76)]. SLE-APS patients were younger and had higher mortality [AOR 4.11 (1.51, 11.3)], neuropsychiatric and hematologic disease. SLE-APLA also had a higher mortality rate [AOR 2.94 (1.06, 8.22)] than the reference group. The mortality was highest in the subset of patients with thrombotic events in the presence of APLA [AOR 7.67 (1.25, 46.9)]. The mere presence of APLA also conferred higher mortality even in the absence of thrombotic events [AOR 3.51 (1.43, 8.63)]. Hematologic manifestations (36.1%) were the most common non-criteria-manifestation. One-third of SLE patients have APLA and its presence is associated with non-criteria hematologic manifestations, arterial thrombosis and higher mortality rate.
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Síndrome Antifosfolípido , Lupus Eritematoso Sistémico , Trombosis , Humanos , Anticuerpos Antifosfolípidos , Anticuerpos Anticardiolipina , Lupus Eritematoso Sistémico/complicaciones , Síndrome Antifosfolípido/complicaciones , Inhibidor de Coagulación del LupusRESUMEN
OBJECTIVES: SLE is associated with significant mortality, and data from South Asia is limited. Thus, we analysed the causes and predictors of mortality and hierarchical cluster-based survival in the Indian SLE Inception cohort for Research (INSPIRE). METHODS: Data for patients with SLE was extracted from the INSPIRE database. Univariate analyses of associations between mortality and a number of disease variables were conducted. Agglomerative unsupervised hierarchical cluster analysis was undertaken using 25 variables defining the SLE phenotype. Survival rates across clusters were assessed using non-adjusted and adjusted Cox proportional-hazards models. RESULTS: Among 2072 patients (with a median follow-up of 18 months), there were 170 deaths (49.2 deaths per 1000 patient-years) of which cause could be determined in 155 patients. 47.1% occurred in the first 6 months. Most of the mortality (n = 87) were due to SLE disease activity followed by coexisting disease activity and infection (n = 24), infections (n = 23), and 21 to other causes. Among the deaths in which infection played a role, 24 had pneumonia. Clustering identified four clusters, and the mean survival estimates were 39.26, 39.78, 37.69 and 35.86 months in clusters 1, 2, 3 and 4, respectively (P < 0.001). The adjusted hazard ratios (HRs) (95% CI) were significant for cluster 4 [2.19 (1.44, 3.31)], low socio-economic-status [1.69 (1.22, 2.35)], number of BILAG-A [1.5 (1.29, 1.73)] and BILAG-B [1.15 (1.01, 1.3)], and need for haemodialysis [4.63 (1.87,11.48)]. CONCLUSION: SLE in India has high early mortality, and the majority of deaths occur outside the health-care setting. Clustering using the clinically relevant variables at baseline may help identify individuals at high risk of mortality in SLE, even after adjusting for high disease activity.
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Autoanticuerpos , Lupus Eritematoso Sistémico , Humanos , Modelos de Riesgos Proporcionales , Tasa de Supervivencia , FenotipoRESUMEN
Iron scarcity provokes a cellular response consisting of the strong expression of high-affinity systems to optimize iron uptake and mobilization. Aft1 is a primary transcription factor involved in iron homeostasis and controls the expression of high-affinity iron uptake genes in Saccharomyces cerevisiae. Aft1 responds to iron deprivation by translocating from the cytoplasm to the nucleus. Here, we demonstrate that the AGC kinase Ypk1, as well as its upstream regulator TOR Complex 2 (TORC2), are required for proper Aft1 nuclear localization following iron deprivation. We exclude a role for TOR Complex 1 (TORC1) and its downstream effector Sch9, suggesting this response is specific for the TORC2 arm of the TOR pathway. Remarkably, we demonstrate that Aft1 nuclear localization and a robust transcriptional response to iron starvation also require biosynthesis of sphingolipids, including complex sphingolipids such as inositol phosphorylceramide (IPC) and upstream precursors, e.g., long-chain bases (LCBs) and ceramides. Furthermore, we observe the deficiency of Aft1 nuclear localization and impaired transcriptional response in the absence of iron when TORC2-Ypk1 is impaired is partially suppressed by exogenous addition of the LCB dihydrosphingosine (DHS). This latter result is consistent with prior studies linking sphingolipid biosynthesis to TORC2-Ypk1 signaling. Taken together, these results reveal a novel role for sphingolipids, controlled by TORC2-Ypk1, for proper localization and activity of Aft1 in response to iron scarcity.
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Proteínas de Saccharomyces cerevisiae , Hierro/metabolismo , Diana Mecanicista del Complejo 2 de la Rapamicina/genética , Diana Mecanicista del Complejo 2 de la Rapamicina/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Transducción de Señal , Esfingolípidos/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismoRESUMEN
OBJECTIVE: To study the prevalence of different NPSLE manifestations in our cohort and to compare clinical and immunological features and outcomes including mortality of patients with NPSLE and SLE controls without NP involvement. METHODS: This was a retrospective study in a tertiary care referral centre. All patients of SLE seen in the last 10 years and fulfilling the SLICC criteria with neuropsychiatric manifestations as per the ACR definitions were included. Patients of SLE without NP involvement were sequentially assigned as controls in a ratio of 1:2. RESULTS: Of the 769 patients diagnosed with SLE from Jan 2011 to December 2020, 128 (16.6%) had NPSLE manifestations as per the ACR definitions. The commonest NPSLE manifestation was seizures (6.5%) followed by cerebrovascular accident (3.9%). NPSLE manifestation occurred at the first presentation of SLE in 99/128 (77.3%) patients and 58 (45.3%) patients had more than one NPSLE manifestation. Lupus anticoagulant and anticardiolipin antibody were tested in 120 patients and were positive in 16 (13.3%) and 12 (10%), respectively. No difference was found in anti-ribosomal p, lupus anticoagulant and anticardiolipin antibodies between the cases and controls. Twenty-one (16.4%) deaths occurred in patients with NPSLE (median follow-up of 40 months) as compared to 13 (5%) in controls (median follow-up of 32 months) (p = <0.001). The cumulative survival of patients with NPSLE was lower as compared to controls (p < 0.001). Relapse of NPSLE was seen in 11(8.6%) patients and was associated with mortality (p = 0.017). CONCLUSIONS: Seizures and cerebrovascular accidents are the commonest NPSLE syndromes in our patients. The presence of NPSLE was associated with high mortality in Indian patients with lupus.
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Síndrome Antifosfolípido , Lupus Eritematoso Sistémico , Vasculitis por Lupus del Sistema Nervioso Central , Accidente Cerebrovascular , Humanos , Estudios Retrospectivos , Vasculitis por Lupus del Sistema Nervioso Central/diagnóstico , Inhibidor de Coagulación del Lupus , Lupus Eritematoso Sistémico/complicaciones , Anticuerpos Anticardiolipina , Síndrome Antifosfolípido/complicaciones , Convulsiones/epidemiologíaRESUMEN
We have investigated the effects that iron limitation provokes in Saccharomyces cerevisiae exponential cultures. We have demonstrated that one primary response is the induction of bulk autophagy mediated by TORC1. Coherently, Atg13 became dephosphorylated whereas Atg1 appeared phosphorylated. The signal of iron deprivation requires Tor2/Ypk1 activity and the inactivation of Tor1 leading to Atg13 dephosphorylation, thus triggering the autophagy process. Iron replenishment in its turn, reduces autophagy flux through the AMPK Snf1 and the subsequent activity of the iron-responsive transcription factor, Aft1. This signalling converges in Atg13 phosphorylation mediated by Tor1. Iron limitation promotes accumulation of trehalose and the increase in stress resistance leading to a quiescent state in cells. All these effects contribute to the extension of the chronological life, in a manner totally dependent on autophagy activation.
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Proteínas Relacionadas con la Autofagia/metabolismo , Hierro/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Autofagia/fisiología , Proteínas de Ciclo Celular/metabolismo , Medios de Cultivo/farmacología , Hierro/administración & dosificación , Mitocondrias/metabolismo , Nutrientes/administración & dosificación , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas , Transporte de Proteínas , Saccharomyces cerevisiae/citología , Saccharomyces cerevisiae/crecimiento & desarrollo , Estrés Fisiológico , Factores de Transcripción/metabolismo , Trehalosa/metabolismoRESUMEN
BACKGROUND: In Mozambique, HIV infection disproportionately affects young adults, particularly women. Despite awareness and knowledge of HIV transmission, many university students have not received HIV testing and continue to engage in high-risk sexual behaviors, including inconsistent condom use. Further understanding of patterns of engagement with HIV prevention and testing is key to reducing HIV transmission in this at-risk population. METHODS: This study used a sequential mixed methods approach to examine patterns of engagement and perceptions of HIV prevention and testing services among higher education students in Mozambique. Survey data were collected from a representative sample of 501 students from Universidade Eduardo Mondlane (UEM) in Maputo, Mozambique to assess the primary outcomes of 1) HIV testing within the last 12 months; and 2) condom use during last sexual encounter. We employed univariate and multivariate regression models. The survey was followed by qualitative interviews with 70 survey participants which were analyzed using an inductive, content-focused analysis to further explain and contextualize survey findings. RESULTS: Over 85% of students reported to be sexually active, among these 74% reported condom use during their last sexual encounter, and 64.2% reported an HIV test within the past 12 months. Females were more likely to have had HIV testing in the past 12 months in comparison to their male peers (aOR 1.82, 95% CI 1.11, 2.99), but were half as likely to have used a condom with their last sexual encounter (aOR 0.52, 95% CI 0.33, 0.83), when controlling for other factors. Qualitative data suggests that these discrepancies may be explained by differential perceptions in risk and trust/mistrust, with women being more concerned about infidelity by their male partner(s) and assuming more responsibility for knowing their own serostatus. Women were also subject to negative stereotypes for possessing condoms in comparison to men, which could explain lower propensity for use. CONCLUSION: Given gendered differences in uptake of condom use and HIV testing, and perceived HIV risk, interventions tailored specifically to male and female students may impact engagement with HIV prevention and testing and empower informed choices about sexual behaviors.
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Infecciones por VIH , Condones , Femenino , Infecciones por VIH/diagnóstico , Infecciones por VIH/prevención & control , Humanos , Masculino , Mozambique , Conducta Sexual , Parejas Sexuales , Estudiantes , Universidades , Adulto JovenRESUMEN
The human monothiol glutaredoxin Glrx3 (PICOT) is ubiquitously distributed in cytoplasm and nuclei in mammalian cells. Its overexpression has been associated with the development of several types of tumors, whereas its deficiency might cause retardation in embryogenesis. Its exact biological role has not been well resolved, although a function as a chaperone distributing iron/sulfur clusters is currently accepted. Yeast humanization and the use of a mouse library have allowed us to find a new partner for PICOT: the human GMP synthase (hGMPs). Both proteins carry out collaborative functions regarding the downregulation of the Saccharomyces cerevisiae Gcn2 pathway under conditions of nutritional stress. Glrx3/hGMPs interact through conserved residues that bridge iron/sulfur clusters and glutathione. This mechanism is also conserved in budding yeast, whose proteins Grx3/Grx4, along with GUA1 (S. cerevisiae GMPs), also downregulate the integrated stress response (ISR) pathway. The heterologous expression of Glrx3/hGMPs efficiently complements Grx3/Grx4. Moreover, the heterologous expression of Glrx3 efficiently complements the novel participation in chronological life span that has been characterized for both Grx3 and Grx4. Our results underscore that the Glrx3/Grx3/Grx4 family presents an evolutionary and functional conservation in signaling events that is partly related to GMP function and contributes to cell life extension.IMPORTANCESaccharomyces cerevisiae is an optimal eukaryotic microbial model to study biological processes in higher organisms despite the divergence in evolution. The molecular function of yeast glutaredoxins Grx3 and Grx4 is enormously interesting, since both proteins are required to maintain correct iron homeostasis and an efficient response to oxidative stress. The human orthologous Glrx3 (PICOT) is involved in a number of human diseases, including cancer. Our research expanded its utility to human cells. Yeast has allowed the characterization of GMP synthase as a new interacting partner for Glrx3 and also for yeast Grx3 and Grx4, the complex monothiol glutaredoxins/GMPs that participate in the downregulation of the activity of the Gcn2 stress pathway. This mechanism is conserved in yeast and humans. Here, we also show that this family of glutaredoxins, Grx3/Grx4/Glrx3, also has a function related to life extension.
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Ligasas de Carbono-Nitrógeno/genética , Proteínas Portadoras/genética , Regulación de la Expresión Génica , Glutarredoxinas/genética , Oxidorreductasas/genética , Proteínas de Saccharomyces cerevisiae/genética , Animales , Ligasas de Carbono-Nitrógeno/metabolismo , Proteínas Portadoras/metabolismo , Biblioteca de Genes , Glutarredoxinas/metabolismo , Humanos , Ratones , Oxidorreductasas/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Transducción de SeñalRESUMEN
Traditional healers are commonly utilised throughout sub-Saharan Africa instead of - and in concert with - biomedical facilities. Traditional healers are trusted providers and prominent community members and could be important partners in improving engagement with HIV services in endemic contexts. Our study sought to understand the roles of healers in the urban setting of Maputo, Mozambique, where HIV prevalence is high and testing rates are low. Qualitative data were gathered through minimally structured interviews with 36 healers. Analysis followed an inductive, grounded theory approach. Data reveal three themes relevant to improving engagement with HIV services in this endemic region: (1) healers have positive attitudes towards biomedicine; (2) healers advocate for their sick clients and (3) clients are reticent to present to biomedical facilities. Healers describe their roles as 'cooperative' with biomedical providers to provide healthcare for their clients. Results suggest that healers could be considered critical enablers to effective HIV programmes in communities. They have social and symbolic capital that positions them to beneficially influence clients and are natural partners for interventions to improve uptake of HIV services.
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Infecciones por VIH , Medicinas Tradicionales Africanas , Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , Instituciones de Salud , Humanos , Mozambique/epidemiología , Investigación CualitativaRESUMEN
Mtl1protein is a cell wall receptor belonging to the CWI pathway. Mtl1 function is related to glucose and oxidative stress signaling. In this report, we show data demonstrating that Mtl1 plays a critical role in the detection of a descent in glucose concentration, in order to activate bulk autophagy machinery as a response to nutrient deprivation and to maintain cell survival in starvation conditions. Autophagy is a tightly regulated mechanism involving several signaling pathways. The data here show that in Saccharomyces cerevisiae, Mtl1 signals glucose availability to either Ras2 or Sch9 proteins converging in Atg1 phosphorylation and autophagy induction. TORC1 complex function is not involved in autophagy induction during the diauxic shift when glucose is limited. In this context, the GCN2 gene is required to regulate autophagy activation upon amino acid starvation independent of the TORC1 complex. Mtl1 function is also involved in signaling the autophagic degradation of mitochondria during the stationary phase through both Ras2 and Sch9, in a manner dependent on either Atg33 and Atg11 proteins and independent of the Atg32 protein, the mitophagy receptor. All of the above suggest a pivotal signaling role for Mtl1 in maintaining correct cell homeostasis function in periods of glucose scarcity in budding yeast.
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Iron is an essential micronutrient that participates as a cofactor in a broad range of metabolic processes including mitochondrial respiration, DNA replication, protein translation and lipid biosynthesis. Adaptation to iron deficiency requires the global reorganization of cellular metabolism directed to optimize iron utilization. The budding yeast Saccharomyces cerevisiae has been widely used to characterize the responses of eukaryotic microorganisms to iron depletion. In this report, we used a genomic approach to investigate the contribution of transcription rates to the modulation of mRNA levels during adaptation of yeast cells to iron starvation. We reveal that a decrease in the activity of all RNA polymerases contributes to the down-regulation of many mRNAs, tRNAs and rRNAs. Opposite to the general expression pattern, many genes including components of the iron deficiency response, the mitochondrial retrograde pathway and the general stress response display a remarkable increase in both transcription rates and mRNA levels upon iron limitation, whereas genes encoding ribosomal proteins or implicated in ribosome biogenesis exhibit a pronounced fall. This expression profile is consistent with an activation of the environmental stress response. The phosphorylation stage of multiple regulatory factors strongly suggests that the conserved nutrient signaling pathway TORC1 is inhibited during the progress of iron deficiency. These results suggest an intricate crosstalk between iron metabolism and the TORC1 pathway that should be considered in many disorders.
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Anemia Ferropénica/genética , Proteínas de Unión al ADN/genética , Hierro/metabolismo , Diana Mecanicista del Complejo 1 de la Rapamicina/genética , Adaptación Fisiológica/genética , Anemia Ferropénica/metabolismo , Proteínas de Unión al ADN/metabolismo , Regulación de la Expresión Génica/genética , Regulación Fúngica de la Expresión Génica/genética , Humanos , Fosforilación , Biosíntesis de Proteínas/genética , ARN Mensajero/genética , Saccharomyces cerevisiae/genéticaRESUMEN
This study explores how urban youth in Mozambique perceive their sexual behaviour and identifies the factors that hinder them from having safer sex in the context of HIV/AIDS, with special emphasis on the condom use. Data was collected form high school students in Maputo, Mozambique. Using a combination of focus group discussions, interviews and informal conversations, it was possible to identify that one major obstacle to the use of condoms was young people's belief that they did not have to use condoms in steady relationships built on love and trust. Trust and love provide a sense of immunity to infection. Such a perception is reinforced, it is argued, by previous HIV/AIDS campaigns in Mozambique that have advocated the use of condoms only with 'occasional sexual partners'. Students' understandings of pleasure, lack of accurate information, lack of sex education at home and at school, and gender inequalities further contribute to making condom use a difficult issue. There should be a change in focus in condom campaigns. Efforts should also be made to encourage young people to 'emotionally invest' in their health by using condoms.
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Conducta del Adolescente/psicología , Coito/psicología , Condones/estadística & datos numéricos , Infecciones por VIH/prevención & control , Conocimientos, Actitudes y Práctica en Salud , Sexo Inseguro/psicología , Adolescente , Adulto , Femenino , Grupos Focales , Infecciones por VIH/psicología , Humanos , Relaciones Interpersonales , Masculino , Mozambique , Narración , Educación Sexual/organización & administración , Parejas Sexuales/psicología , Medio Social , Encuestas y CuestionariosRESUMEN
O presente estudo explora as percepções e práticas sexuais entre jovens no Moçambique pós-colonial e pós-socialista, especificamente na cidade de Maputo. Usando uma combinação de diferentes métodos qualitativos, o estudo analisa profundamente relações de namoro. As relações de namoro, onde a relação sexual toma, preferencialmente, a forma de sexo não protegido (sem o uso do preservativo) - "sexo verdadeiro" - são reciprocadas pelo amor e pela proposta de um compromisso por parte do jovem. Assim, verifica-se um sistema de trocas de presentes que neste estudo é analisado a partir do quadro teórico do dom de Marcel Mauss (1969). Mas, devido ao fato de a grande maioria dos jovens que participaram do estudo praticar a monogamia serial e à existência de parceiros ocasionais com quem o sexo protegido nem sempre é praticado, existem potenciais grandes riscos para infecção com ITSs e HIV/Aids. Assim, a troca de amor por sexo constitui um presente perigoso, pois põe em risco a saúde e a vida desses jovens.
This study explores the perceptions and the sexual practices of young men and women in post colonial and post socialist Mozambique, specifically in Maputo city. Using a combination of various qualitative methods, the study performs an in-depth analysis of stable relationships called namoro. The namoro relationships, where people preferably engage in non-protected sex (no condom use) - "real sex" are exchanged by the declaration of love and the proposal for a serious commitment from the young man to the young woman. Therefore, there is a gift exchange system which, in this study, is analyzed under the theoretical framework of the gift of Marcel Mauss (1969). However, since a great part of the young people in this study practice serial monogamy and due to the existence of occasional partners with whom protected sex is not always practiced, there are potential risks to STIs and HIV/Aids infection. Thus, the exchange of sex for love is translated into a very dangerous gift, as it puts the health and the lives of these youngsters at risk.