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1.
BMC Cardiovasc Disord ; 24(1): 243, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38724901

RESUMEN

BACKGROUND: The aim of this study was to evaluate the recovery rate of the left ventricular systolic function of women diagnosed with peripartum cardiomyopathy receiving specialized care in rural Tanzania. METHODS: In this observational study, women diagnosed with peripartum cardiomyopathy at a referral center in rural Tanzania between December 2015 and September 2021 were included. Women diagnosed between February and September 2021 were followed prospectively, those diagnosed between December 2015 and January 2021 were tracked back for a follow-up echocardiography. All participants received a clinical examination, a comprehensive echocardiogram, and a prescription of guideline-directed medical therapy. The primary outcome was recovery of the left ventricular systolic function (left ventricular ejection fraction > 50%). RESULTS: Median age of the 110 participants was 28.5 years (range 17-45). At enrolment, 49 (45%) participants were already on cardiac medication, 50 (45%) had severe eccentric hypertrophy of the left ventricle, and the median left ventricular ejection fraction was 30% (range 15-46). After a median follow-up of 8.98 months (IQR 5.72-29.37), 61 (55%) participants were still on cardiac medication. Full recovery of the left ventricular systolic function was diagnosed in 76 (69%, 95% CI 59.6-77.6%) participants. In the multivariate analysis, a higher left ventricular ejection fraction at baseline was positively associated with full recovery (each 5% increase; OR 1.7, 95% CI 1.10-2.62, p = 0.012), while higher age was inversely associated (each 10 years increase; OR 0.40, 95% CI 0.19-0.82, p = 0.012). CONCLUSION: Left ventricular systolic function recovered completely in 69% of study participants with peripartum cardiomyopathy from rural Tanzania under specialized care.


Asunto(s)
Cardiomiopatías , Periodo Periparto , Complicaciones Cardiovasculares del Embarazo , Recuperación de la Función , Volumen Sistólico , Sístole , Función Ventricular Izquierda , Humanos , Femenino , Adulto , Tanzanía/epidemiología , Adulto Joven , Adolescente , Embarazo , Cardiomiopatías/fisiopatología , Cardiomiopatías/diagnóstico por imagen , Cardiomiopatías/diagnóstico , Factores de Tiempo , Persona de Mediana Edad , Complicaciones Cardiovasculares del Embarazo/fisiopatología , Complicaciones Cardiovasculares del Embarazo/diagnóstico por imagen , Complicaciones Cardiovasculares del Embarazo/diagnóstico , Complicaciones Cardiovasculares del Embarazo/tratamiento farmacológico , Resultado del Tratamiento , Estudios Prospectivos , Salud Rural , Disfunción Ventricular Izquierda/fisiopatología , Disfunción Ventricular Izquierda/diagnóstico por imagen , Disfunción Ventricular Izquierda/diagnóstico , Trastornos Puerperales/fisiopatología , Trastornos Puerperales/diagnóstico , Trastornos Puerperales/terapia , Trastornos Puerperales/tratamiento farmacológico
2.
Clin Infect Dis ; 76(6): 1013-1021, 2023 03 21.
Artículo en Inglés | MEDLINE | ID: mdl-36331957

RESUMEN

BACKGROUND: Patients with suspected extrapulmonary tuberculosis are often treated empirically. We hypothesized that extended focused assessment with sonography for human immunodeficiency virus (HIV) and tuberculosis (eFASH), in combination with other tests, would increase the proportion of correctly managed patients with suspected extrapulmonary tuberculosis. METHODS: This trial in adults with suspected extrapulmonary tuberculosis was performed in a rural and an urban hospital in Tanzania. Participants were randomized 1:1 to intervention or routine care, stratified by site and HIV status. All participants underwent clinical evaluation, chest radiography, and testing with sputum Xpert MTB/RIF and urine Xpert MTB/RIF Ultra assays. The intervention was a management algorithm based on results of eFASH plus microbiology, adenosine deaminase (ADA), and chest radiography. The primary outcome was the proportion of correctly managed patients. The presence of positive microbiological or ADA results defined definite tuberculosis. An independent end-point review committee determined diagnoses of probable or no tuberculosis. We evaluated outcomes using logistic regression models, adjusted for randomization stratification factors. RESULTS: From September 2018 to October 2020, a total of 1036 patients were screened and 701 were randomized (350 to the intervention and 351 to the control group). Of participants in the intervention group, 251 (72%) had a positive eFASH outcome. In 258 (74%) of the intervention and 227 (65%) of the control participants antituberculosis was initiated treatment at baseline. More intervention participants had definite tuberculosis (n = 124 [35%]), compared with controls (n = 85 [24%]). There was no difference between groups for the primary outcome (intervention group, 266 of 286 [93%]; control group, 245 of 266 [92%]; odds ratio, 1.14 [95% confidence interval: .60-2.16]; P = .68). There were no procedure-associated adverse events. CONCLUSIONS: eFASH did not change the proportion of correctly managed patients but increased the proportion of those with definite tuberculosis. CLINICAL TRIALS REGISTRATION: Pan African Registry: PACTR201712002829221.


Asunto(s)
Infecciones por VIH , Tuberculosis Extrapulmonar , Tuberculosis , Adulto , Humanos , Tuberculosis/diagnóstico por imagen , Tuberculosis/tratamiento farmacológico , Tanzanía , Esputo/microbiología
3.
Malar J ; 22(1): 210, 2023 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-37454145

RESUMEN

BACKGROUND: Plasmodium falciparum cysteine-rich protective antigen (PfCyRPA) is an invasion complex protein essential for erythrocyte invasion. In contrast to several previously clinically tested merozoite vaccine candidate antigens, PfCyRPA is not polymorphic, making it a promising candidate antigen for blood stage vaccine development. METHODS: Mice and rabbits were immunized with vaccine formulations of recombinantly expressed PfCyRPA adjuvanted either with the glucopyranosyl lipid A (GLA) containing adjuvants GLA-LSQ, GLA-SE, GLA-Alum or with Nanoalum. ELISA and indirect immunofluorescence assays (IFA) were used to analyse elicited IgG titers and the P. falciparum growth inhibitory activity was determined with a standardized in vitro [3H]-hypoxanthine incorporation assay. RESULTS: In the mouse experiments, the GLA adjuvanted formulations were superior to the Nanoalum formulation with respect to antibody titer development, IFA sero-conversion rates and in vitro parasite growth-inhibitory activity. In rabbits, the highest titers of parasite growth inhibitory antibodies were obtained with the GLA-SE formulation. Comparable mean ELISA IgG endpoint titers were reached in rabbits after three immunizations with GLA-SE adjuvanted PfCyRPA doses of 5, 25 and 100 µg, but with 100 µg of antigen, only two immunizations were required to reach this titer. CONCLUSION: PfCyRPA formulated with the human-compatible adjuvant GLA-SE represents an attractive vaccine candidate for early clinical testing in a controlled P. falciparum blood stage challenge trial.


Asunto(s)
Vacunas contra la Malaria , Malaria Falciparum , Parásitos , Animales , Ratones , Humanos , Conejos , Receptor Toll-Like 4 , Lípido A , Plasmodium falciparum , Adyuvantes Inmunológicos , Antígenos de Protozoos , Proteínas Protozoarias , Malaria Falciparum/prevención & control , Animales de Laboratorio , Adyuvantes Farmacéuticos , Inmunoglobulina G , Anticuerpos Antiprotozoarios
4.
BMC Health Serv Res ; 23(1): 677, 2023 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-37349790

RESUMEN

BACKGROUND: Adolescents have special sexual and reproductive health (ASRH) needs and are susceptible to poor health outcomes. The global burden of ill sexual health includes a significant proportion of Adolescents. The existing ASRH services in Ethiopia and particularly in the Afar region are currently not well suited to meet the needs of pastoralist adolescents. This study assesses the level of ASRH service utilization among pastoralists in Afar regional state, Ethiopia. METHOD: A community based cross-sectional study was conducted from January to March 2021 in four randomly chosen pastoralist villages or kebeles of Afar, Ethiopia. A multistage cluster sampling procedure was used to select 766 volunteer adolescents aged 10-19. SRH services uptake was measured asking whether they had used any SRH service components during the last year. Data was collected through face-to-face interviews with a structured questionnaire; data entry was done with Epi info 3.5.1. Logistic regression analyses was used to assess associations with SRH service uptake. SPSS version 23 statistical software package was used for advanced logistic regression analyses to assess the associations between dependent and predictor variables. RESULTS: The study revealed that two-thirds or 513 (67%) of the respondents are aware of ASRH services. However, only one-fourth (24.5%) of the enrolled adolescents used at least one ASRH service in the past twelve months. ASRH services utilization was significantly associated with gender (being female [AOR = 1.87 (CI 1.29-2.70)], being in school [AOR = 2.38(CI: 1.05-5.41), better family income [AOR = 10.92 (CI; 7.10-16.80)], prior discussions of ASRH issues [AOR = 4.53(CI: 2.52, 8.16)], prior sexual exposure [AOR = 4.75(CI: 1.35-16.70)], and being aware of ASRH services [AOR = 1.96 (CI: 1.02-3.822)]. Being pastoralist, religious and cultural restrictions, fear of it becoming known by parents, services not being available, income, and lack of knowledge were found to deter ASRH service uptake. CONCLUSION: Addressing ASRH needs of pastoralist adolescents is more urgent than ever, sexual health problems are increasing where these groups face broad hurdles to SRH service uptake. Although Ethiopian national policy has created an enabling environment for ASRH, multiple implementation issues require special attention to such neglected groups. "Gender-culture-context-appropriate" interventions are favorable to identify and meet the diverse needs of Afar pastoralist adolescents. Afar regional education bureau and concerned stakeholders need to improve adolescent education to overcome social barriers (e.g. humiliation, disgrace, and deterring gender norms) against ASRH services through community outreach programs. In addition, economic empowerment, peer education, adolescent counseling, and parent-youth communication will help address sensitive ASRH issues.


Asunto(s)
Servicios de Salud Reproductiva , Adolescente , Femenino , Humanos , Masculino , Estudios Transversales , Etiopía , Salud Reproductiva , Conducta Sexual , Niño , Adulto Joven
5.
HIV Med ; 23(6): 661-672, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-34964236

RESUMEN

OBJECTIVES: Pill count is used to assess drug adherence in people living with HIV (PLHIV). Carrying a pillbox is associated with fear of concealment and stigma and might indicate poor adherence and predict someone who will be lost to follow-up (LTFU). We therefore assessed the association between pillbox return and being LTFU in rural Tanzania. METHODS: This is a nested study of the Kilombero and Ulanga Antiretroviral Cohort (KIULARCO). We included PLHIV aged ≥ 18 years enrolled in KIULARCO between January 2013 and March 2019 with follow-up through January 2020, who were on antiretroviral treatment (ART) for ≥ 6 months. Baseline was defined as the latest ART initiation or KIULARCO enrolment. We determined the association between time-dependent failed pillbox return updated at every visit and LTFU using Kaplan-Meier estimation and Cox models. RESULTS: Among 2552 PLHIV included in the study, 1735 (68.0%) were female, 959 (40.3%) had a WHO stage III/IV and 1487 (66.4%) had a CD4 cell count < 350 cells/µL. The median age was 38.4 years [interquartile range (IQR): 31.7-46.2]. During a median follow-up of 33.1 months (IQR: 17.5-52.4), 909 (35.6%) participants were LTFU, 43 (1.7%) died and 194 (7.6%) had transferred to another clinic. The probability of being LTFU was higher among PLHIV with failed pillbox return than among those who returned their pillbox [30.0%, 95% confidence interval (CI): 26.8-33.2% vs. 19.4%, 95% CI: 17.4-21.6%, respectively, at 24 months (hazard ratio = 1.67, 95% CI: 1.46-1.90; p < 0.001)]. CONCLUSIONS: Failed pillbox return was associated with a higher risk of being LTFU and could be used as a simple tool to identify PLHIV for appropriate interventions to reduce their chance of being LTFU.


Asunto(s)
Infecciones por VIH , Adulto , Antirretrovirales/uso terapéutico , Recuento de Linfocito CD4 , Femenino , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Humanos , Perdida de Seguimiento , Masculino , Tanzanía/epidemiología
6.
BMC Infect Dis ; 22(1): 37, 2022 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-34991496

RESUMEN

BACKGROUND: Nearly half of HIV-related deaths occur in East and Southern Africa, yet data on causes of death (COD) are scarce. We determined COD and associated factors among people living with HIV (PLHIV) in rural Tanzania. METHODS: PLHIV attending the Chronic Diseases Clinic of Ifakara, Morogoro are invited to enrol in the Kilombero and Ulanga Antiretroviral Cohort (KIULARCO). Among adults (≥ 15 years) enrolled in 2005-2018, with follow-up through April 2019, we classified COD in comprehensive classes and as HIV- or non-HIV-related. In the subset of participants enrolled in 2013-2018 (when data were more complete), we assessed cause-specific mortality using cumulative incidences, and associated factors using proportional hazards models. RESULTS: Among 9871 adults (65% female, 26% CD4 count < 100 cells/mm3), 926 (9%) died, among whom COD were available for 474 (51%), with missing COD mainly in earlier years. The most common COD were tuberculosis (N = 127, 27%), non-AIDS-related infections (N = 72, 15%), and other AIDS-related infections (N = 59, 12%). Cardiovascular and renal deaths emerged as important COD in later calendar years, with 27% of deaths in 2018 attributable to cardiovascular causes. Most deaths (51%) occurred within the first six months following enrolment. Among 3956 participants enrolled in 2013-2018 (N = 203 deaths, 200 with COD ascertained), tuberculosis persisted as the most common COD (25%), but substantial proportions of deaths from six months after enrolment onwards were attributable to renal (14%), non-AIDS-related infections (13%), other AIDS-related infections (10%) and cardiovascular (10%) causes. Factors associated with higher HIV-related mortality were sex, younger age, living in Ifakara town, HIV status disclosure, hospitalisation, not being underweight, lower CD4 count, advanced WHO stage, and gaps in care. Factors associated with higher non-HIV-related mortality included not having an HIV-positive partner, lower CD4 count, advanced WHO stage, and gaps in care. CONCLUSION: Incidence of HIV-related mortality was higher than that of non-HIV-related mortality, even in more recent years, likely due to late presentation. Tuberculosis was the leading specific COD identified, particularly soon after enrolment, while in later calendar years cardiovascular and renal causes emerged as important, emphasising the need for improved screening and management.


Asunto(s)
Infecciones por VIH , Antirretrovirales/uso terapéutico , Causas de Muerte , Femenino , Estudios de Seguimiento , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Humanos , Masculino , Tanzanía/epidemiología
7.
Proc Natl Acad Sci U S A ; 116(18): 8895-8900, 2019 04 30.
Artículo en Inglés | MEDLINE | ID: mdl-31004062

RESUMEN

Alzheimer's disease (AD) is characterized by the deposition of ß-sheet-rich, insoluble amyloid ß-peptide (Aß) plaques; however, plaque burden is not correlated with cognitive impairment in AD patients; instead, it is correlated with the presence of toxic soluble oligomers. Here, we show, by a variety of different techniques, that these Aß oligomers adopt a nonstandard secondary structure, termed "α-sheet." These oligomers form in the lag phase of aggregation, when Aß-associated cytotoxicity peaks, en route to forming nontoxic ß-sheet fibrils. De novo-designed α-sheet peptides specifically and tightly bind the toxic oligomers over monomeric and fibrillar forms of Aß, leading to inhibition of aggregation in vitro and neurotoxicity in neuroblastoma cells. Based on this specific binding, a soluble oligomer-binding assay (SOBA) was developed as an indirect probe of α-sheet content. Combined SOBA and toxicity experiments demonstrate a strong correlation between α-sheet content and toxicity. The designed α-sheet peptides are also active in vivo where they inhibit Aß-induced paralysis in a transgenic Aß Caenorhabditis elegans model and specifically target and clear soluble, toxic oligomers in a transgenic APPsw mouse model. The α-sheet hypothesis has profound implications for further understanding the mechanism behind AD pathogenesis.


Asunto(s)
Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/química , Estructura Secundaria de Proteína , Péptidos beta-Amiloides/metabolismo , Animales , Anticuerpos , Encéfalo/metabolismo , Encéfalo/patología , Caenorhabditis elegans , Humanos , Immunoblotting , Ratones , Agregado de Proteínas , Agregación Patológica de Proteínas
8.
Neurobiol Dis ; 150: 105237, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33383188

RESUMEN

A pathological characteristic of repetitive traumatic brain injury (TBI) is the deposition of hyperphosphorylated and aggregated tau species in the brain and increased levels of extracellular monomeric tau are believed to play a role in the pathogenesis of neurodegenerative tauopathies. The pathways by which extracellular tau is eliminated from the brain, however, remains elusive. The purpose of this study was to examine tau uptake by cerebrovascular cells and the effect of TBI on these processes. We found monomeric tau interacts with brain vascular mural cells (pericytes and smooth muscle cells) to a greater extent than other cerebrovascular cells, indicating mural cells may contribute to the elimination of extracellular tau, as previously described for other solutes such as beta-amyloid. Consistent with other neurodegenerative disorders, we observed a progressive decline in cerebrovascular mural cell markers up to 12 months post-injury in a mouse model of repetitive mild TBI (r-mTBI) and human TBI brain specimens, when compared to control. These changes appear to reflect mural cell degeneration and not cellular loss as no difference in the mural cell population was observed between r-mTBI and r-sham animals as determined through flow cytometry. Moreover, freshly isolated r-mTBI cerebrovessels showed reduced tau uptake at 6 and 12 months post-injury compared to r-sham animals, which may be the result of diminished cerebrovascular endocytosis, as caveolin-1 levels were significantly decreased in mouse r-mTBI and human TBI cerebrovessels compared to their respective controls. Further emphasizing the interaction between mural cells and tau, similar reductions in mural cell markers, tau uptake, and caveolin-1 were observed in cerebrovessels from transgenic mural cell-depleted animals. In conclusion, our studies indicate repeated injuries to the brain causes chronic mural cell degeneration, reducing the caveolar-mediated uptake of tau by these cells. Alterations in tau uptake by vascular mural cells may contribute to tau deposition in the brain following head trauma and could represent a novel therapeutic target for TBI or other neurodegenerative disorders.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Conmoción Encefálica/metabolismo , Encéfalo/metabolismo , Células Endoteliales/metabolismo , Microglía/metabolismo , Miocitos del Músculo Liso/metabolismo , Pericitos/metabolismo , Proteínas tau/metabolismo , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/genética , Precursor de Proteína beta-Amiloide/genética , Animales , Encéfalo/irrigación sanguínea , Caveolina 1/metabolismo , Femenino , Humanos , Masculino , Ratones , Ratones Transgénicos , Músculo Liso Vascular/citología , Presenilina-1/genética , Recurrencia
9.
J Antimicrob Chemother ; 76(10): 2681-2689, 2021 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-34337653

RESUMEN

BACKGROUND: The extent to which drug-drug interactions (DDIs) between antiretrovirals (ARVs) and co-medications are recognized and managed has not been thoroughly evaluated in limited-resource settings. OBJECTIVES: This prospective questionnaire-based study aimed to determine the prevalence and risk factors for unrecognized/incorrectly managed DDIs in people living with HIV followed-up at the Chronic Diseases Clinic of Ifakara (CDCI) and enrolled in the Kilombero and Ulanga Antiretroviral Cohort (KIULARCO). METHODS: We prospectively included ARV-treated adults receiving ≥1 co-medication coming for a follow-up visit at the CDCI between March and July 2017. Using a structured questionnaire, physicians were requested to identify potentially clinically significant DDIs in the prescribed treatment, to provide recommendations for their management and to indicate any hurdles to implement the recommendations. Prescriptions were subsequently screened for DDIs using the Liverpool DDIs database. Identified clinically significant DDIs and their recommended management according to the DDIs database were compared with the information provided in the questionnaires. RESULTS: Among 334 participants, the median age was 47 years (IQR = 40-56 years), 69% were female and 82% had ≥1 non-communicable disease (NCD). Overall, 129 participants had ≥1 clinically relevant DDI, which was not recognized and/or incorrectly managed in 56 participants (43%). Of those, 6 (11%) were due to limited monitoring options or medication affordability issues. In the multivariable logistic regression, the presence of ≥1 NCD was associated with an increased risk for unrecognized/incorrect DDI management (OR = 15.8; 95% CI = 1.8-139.6). CONCLUSIONS: Recognition/appropriate management of DDIs is suboptimal, highlighting the need for educational programmes, pharmacovigilance activities and increased access to medications and monitoring options. This should become a focus of HIV programmes given the increasing burden of NCDs in sub-Saharan Africa.


Asunto(s)
Infecciones por VIH , Preparaciones Farmacéuticas , Adulto , Interacciones Farmacológicas , Femenino , Infecciones por VIH/tratamiento farmacológico , Humanos , Persona de Mediana Edad , Estudios Prospectivos , Encuestas y Cuestionarios , Tanzanía/epidemiología
10.
BMC Neurosci ; 22(1): 39, 2021 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-34034683

RESUMEN

BACKGROUND: Matrix metallopeptidase 9 (MMP9) has been implicated in a variety of neurological disorders, including Alzheimer's disease (AD), where MMP9 levels are elevated in the brain and cerebrovasculature. Previously our group demonstrated apolipoprotein E4 (apoE4) was less efficient in regulating MMP9 activity in the brain than other apoE isoforms, and that MMP9 inhibition facilitated beta-amyloid (Aß) elimination across the blood-brain barrier (BBB) METHODS: In the current studies, we evaluated the impact of MMP9 modulation on Aß disposition and neurobehavior in AD using two approaches, (1) pharmacological inhibition of MMP9 with SB-3CT in apoE4 x AD (E4FAD) mice, and (2) gene deletion of MMP9 in AD mice (MMP9KO/5xFAD) RESULTS: Treatment with the MMP9 inhibitor SB-3CT in E4FAD mice led to reduced anxiety compared to placebo using the elevated plus maze. Deletion of the MMP9 gene in 5xFAD mice also reduced anxiety using the open field test, in addition to improving sociability and social recognition memory, particularly in male mice, as assessed through the three-chamber task, indicating certain behavioral alterations in AD may be mediated by MMP9. However, neither pharmacological inhibition of MMP9 or gene deletion of MMP9 affected spatial learning or memory in the AD animals, as determined through the radial arm water maze. Moreover, the effect of MMP9 modulation on AD neurobehavior was not due to changes in Aß disposition, as both brain and plasma Aß levels were unchanged in the SB-3CT-treated E4FAD animals and MMP9KO/AD mice compared to their respective controls. CONCLUSIONS: In total, while MMP9 inhibition did improve specific neurobehavioral deficits associated with AD, such as anxiety and social recognition memory, modulation of MMP9 did not alter spatial learning and memory or Aß tissue levels in AD animals. While targeting MMP9 may represent a therapeutic strategy to mitigate aspects of neurobehavioral decline in AD, further work is necessary to understand the nature of the relationship between MMP9 activity and neurological dysfunction.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Ansiedad/metabolismo , Metaloproteinasa 9 de la Matriz/deficiencia , Interacción Social , Aprendizaje Espacial/fisiología , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/psicología , Péptidos beta-Amiloides/genética , Animales , Ansiedad/tratamiento farmacológico , Ansiedad/genética , Ansiedad/psicología , Encéfalo/metabolismo , Femenino , Compuestos Heterocíclicos con 1 Anillo/farmacología , Compuestos Heterocíclicos con 1 Anillo/uso terapéutico , Masculino , Metaloproteinasa 9 de la Matriz/genética , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Actividad Motora/efectos de los fármacos , Actividad Motora/fisiología , Presenilina-1/genética , Interacción Social/efectos de los fármacos , Aprendizaje Espacial/efectos de los fármacos , Sulfonas/farmacología , Sulfonas/uso terapéutico
11.
Bioorg Chem ; 109: 104732, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33639364

RESUMEN

Candida rugosa lipase (CRL) is an enzyme commonly used in medicinal and biotechnological applications. Allosteric modulators of CRL could aid in modifying lipase-related diseases as well as improving biotechnological processes. Thus, a combinatorial approach of computational in-silico and high-throughput in-vitro screening was used to identify allosteric modulators of CRL. The screening of natural product libraries resulted in 132 compounds of which 53 were tested in-vitro. Subsequently, four inhibitors and three enhancers were identified of which rutin and cynaroside represented the strongest inhibitors of CRL activity (IC50: 227 ± 26 µM and 446 ± 15 µM, respectively) and NP-008496 the strongest enhancer (EC50: 425 ± 18 µM). All three compounds were predicted to bind the same allosteric site suggesting a common mechanism. Therefore, the present study demonstrated a reliable work-flow, identified an allosteric site of CRL and determined inhibitors and enhancers with numerous potential medical and biotechnological applications.


Asunto(s)
Productos Biológicos/farmacología , Inhibidores Enzimáticos/farmacología , Lipasa/metabolismo , Saccharomycetales/enzimología , Sitio Alostérico/efectos de los fármacos , Productos Biológicos/síntesis química , Productos Biológicos/química , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Cinética , Simulación del Acoplamiento Molecular , Estructura Molecular , Relación Estructura-Actividad
12.
J Biol Chem ; 294(36): 13378-13395, 2019 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-31324720

RESUMEN

Spleen tyrosine kinase (SYK) plays a major role in inflammation and in adaptive immune responses and could therefore contribute to the neuroinflammation observed in various neurodegenerative diseases. Indeed, previously we have reported that SYK also regulates ß-amyloid (Aß) production and hyperphosphorylation of Tau protein involved in these diseases. Moreover, SYK hyperactivation occurs in a subset of activated microglia, in dystrophic neurites surrounding Aß deposits, and in neurons affected by Tau pathology both in individuals with Alzheimer's disease (AD) and in AD mouse models. SYK activation increases Tau phosphorylation and accumulation, suggesting that SYK could be an attractive target for treating AD. However, the mechanism by which SYK affects Tau pathology is not clear. In this study, using cell biology and biochemical approaches, along with immunoprecipitation and immunoblotting, quantitative RT-PCR, and ELISAs, we found that SYK inhibition increases autophagic Tau degradation without impacting Tau production. Using neuron-like SH-SY5Y cells, we demonstrate that SYK acts upstream of the mammalian target of rapamycin (mTOR) pathway and that pharmacological inhibition or knockdown of SYK decreases mTOR pathway activation and increases autophagic Tau degradation. Interestingly, chronic SYK inhibition in a tauopathy mouse model profoundly reduced Tau accumulation, neuroinflammation, neuronal and synaptic loss, and also reversed defective autophagy. Our results further suggest that the SYK up-regulation observed in the brains of individuals with AD contributes to defective autophagic clearance leading to the accumulation of pathogenic Tau species. These findings further highlight SYK as a therapeutic target for the treatment of tauopathies and other neurodegenerative proteinopathies associated with defective autophagic clearance.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Autofagia , Quinasa Syk/metabolismo , Proteínas tau/metabolismo , Animales , Ratones , Ratones Endogámicos C57BL
13.
BMC Infect Dis ; 20(1): 349, 2020 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-32414338

RESUMEN

BACKGROUND: Patients with clinically suspected tuberculosis are often treated empirically, as diagnosis - especially of extrapulmonary tuberculosis - remains challenging. This leads to an overtreatment of tuberculosis and to underdiagnosis of possible differential diagnoses. METHODS: This open-label, parallel-group, superiority randomized controlled trial is done in a rural and an urban center in Tanzania. HIV-positive and -negative adults (≥18 years) with clinically suspected extrapulmonary tuberculosis are randomized in a 1:1 ratio to an intervention- or control group, stratified by center and HIV status. The intervention consists of a management algorithm including extended focused assessment of sonography for HIV and tuberculosis (eFASH) in combination with chest X-ray and microbiological tests. Treatment with anti-tuberculosis drugs is started, if eFASH is positive, chest X-ray suggests tuberculosis, or a microbiological result is positive for tuberculosis. Patients in the control group are managed according national guidelines. Treatment is started if microbiology is positive or empirically according to the treating physician. The primary outcome is the proportion of correctly managed patients at 6 months (i.e patients who were treated with anti-tuberculosis treatment and had definite or probable tuberculosis, and patients who were not treated with anti-tuberculosis treatment and did not have tuberculosis). Secondary outcomes are the proportion of symptom-free patients at two and 6 months, and time to death. The sample size is 650 patients. DISCUSSION: This study will determine, whether ultrasound in combination with other tests can increase the proportion of correctly managed patients with clinically suspected extrapulmonary tuberculosis, thus reducing overtreatment with anti-tuberculosis drugs. TRIAL REGISTRATION: PACTR, Registration number: PACTR201712002829221, registered December 1st 2017.


Asunto(s)
Tuberculosis/diagnóstico por imagen , Ultrasonografía/métodos , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Radiografía , Tanzanía
14.
BMC Infect Dis ; 20(1): 773, 2020 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-33076866

RESUMEN

BACKGROUND: Globally, the majority of people living with HIV have no or only limited access to HIV drug resistance testing to guide the selection of antiretroviral drugs. This is of particular concern for children and adolescents, who experience high rates of treatment failure. The GIVE MOVE trial assesses the clinical impact and cost-effectiveness of routinely providing genotypic resistance testing (GRT) to children and adolescents living with HIV who have an unsuppressed viral load (VL) while taking antiretroviral therapy (ART). METHODS: GIVE MOVE is an open-label randomised clinical trial enrolling children and adolescents (≥6 months to <19 years) living with HIV with a VL ≥400 copies/mL (c/mL) while taking first-line ART. Recruitment takes place at sites in Lesotho and Tanzania. Participants are randomised in a 1:1 allocation to a control arm receiving the standard of care (3 sessions of enhanced adherence counselling, a follow-up VL test, continuation of the same regimen upon viral resuppression or empiric selection of a new regimen upon sustained elevated viremia) and an intervention arm (GRT to inform onward treatment). The composite primary endpoint is the occurrence of any one or more of the following events during the 36 weeks of follow-up period: i) death due to any cause; ii) HIV- or ART-related hospital admission of ≥24 h duration; iii) new clinical World Health Organisation stage 4 event (excluding lymph node tuberculosis, stunting, oral or genital herpes simplex infection and oesophageal candidiasis); and iv) no documented VL <50 c/mL at 36 weeks follow-up. Secondary and exploratory endpoints assess additional health-related outcomes, and a nested study will assess the cost-effectiveness of the intervention. Enrolment of a total of 276 participants is planned, with an interim analysis scheduled after the first 138 participants have completed follow-up. DISCUSSION: This randomised clinical trial will assess if the availability of resistance testing improves clinical outcomes in children and adolescents with elevated viremia while taking ART. TRIAL REGISTRATION: This trial is registered with ClinicalTrials.gov ( NCT04233242 ; registered 18.01.2020). More information: www.givemove.org .


Asunto(s)
Fármacos Anti-VIH/farmacología , Farmacorresistencia Viral , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , VIH/efectos de los fármacos , Adolescente , Fármacos Anti-VIH/uso terapéutico , Niño , Preescolar , Análisis Costo-Beneficio , Consejo , Femenino , Genotipo , Herpes Genital , Humanos , Lactante , Lesotho , Estudios Longitudinales , Masculino , Tanzanía , Insuficiencia del Tratamiento , Carga Viral , Viremia/tratamiento farmacológico , Viremia/virología
15.
Clin Infect Dis ; 68(5): 738-747, 2019 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-30020447

RESUMEN

BACKGROUND: Murine typhus, or infection with Rickettsia typhi, is a global but neglected disease without randomized clinical trials to guide antibiotic therapy. METHODS: A prospective, open, randomized trial was conducted in nonpregnant, consenting inpatient adults with rapid diagnostic test evidence of uncomplicated murine typhus at 2 hospitals in Vientiane, Laos. Patients were randomized to 7 days (D7) or 3 days (D3) of oral doxycycline or 3 days of oral azithromycin (A3). Primary outcome measures were fever clearance time and frequencies of treatment failure and relapse. RESULTS: Between 2004 and 2009, the study enrolled 216 patients (72 per arm); 158 (73.2%) had serology/polymerase chain reaction (PCR)-confirmed murine typhus, and 52 (24.1%) were R. typhi PCR positive. The risk of treatment failure was greater for regimen A3 (22.5%; 16 of 71 patients) than for D3 (4.2%; 3 of 71) or D7 (1.4%; 1 of 71) (P < .001). Among R. typhi PCR-positive patients, the area under the time-temperature curve and the fever clearance time were significantly higher for A3 than for D3 (1.8- and 1.9-fold higher, respectively; P = .005) and D7 (1.5- and 1.6-fold higher; P = .02). No patients returned with PCR-confirmed R. typhi relapse. CONCLUSION: In Lao adults, azithromycin is inferior to doxycycline as oral therapy for uncomplicated murine typhus. For doxycycline, 3- and 7-day regimens have similar efficacy. Azithromycin use in murine typhus should be reconsidered. Investigation of genomic and phenotypic markers of R. typhi azithromycin resistance is needed. CLINICAL TRIAL REGISTRATION: ISRCTN47812566.


Asunto(s)
Antibacterianos/uso terapéutico , Azitromicina/uso terapéutico , Doxiciclina/uso terapéutico , Tifus Endémico Transmitido por Pulgas/tratamiento farmacológico , Adulto , Femenino , Humanos , Laos/epidemiología , Masculino , Enfermedades Desatendidas/tratamiento farmacológico , Enfermedades Desatendidas/epidemiología , Estudios Prospectivos , Tifus Endémico Transmitido por Pulgas/epidemiología , Adulto Joven
16.
N Engl J Med ; 375(10): 954-61, 2016 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-27602667

RESUMEN

Scrub typhus is a life-threatening zoonosis caused by Orientia tsutsugamushi organisms that are transmitted by the larvae of trombiculid mites. Endemic scrub typhus was originally thought to be confined to the so called "tsutsugamushi triangle" within the Asia-Pacific region. In 2006, however, two individual cases were detected in the Middle East and South America, which suggested that the pathogen was present farther afield. Here, we report three autochthonous cases of scrub typhus caused by O. tsutsugamushi acquired on Chiloé Island in southern Chile, which suggests the existence of an endemic focus in South America. (Funded by the Chilean Comisión Nacional de Investigación Científica y Tecnológica and the Wellcome Trust.).


Asunto(s)
Enfermedades Endémicas , Orientia tsutsugamushi , Tifus por Ácaros , Adulto , Animales , Vectores Arácnidos , Chile , Femenino , Humanos , Masculino , Persona de Mediana Edad , Orientia tsutsugamushi/genética , Orientia tsutsugamushi/aislamiento & purificación , Filogenia , Tifus por Ácaros/diagnóstico , Tifus por Ácaros/microbiología , Tifus por Ácaros/transmisión , Trombiculidae/microbiología
17.
J Antimicrob Chemother ; 74(1): 74-81, 2019 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-30295746

RESUMEN

Objectives: To develop a method to enable the large-scale antimicrobial susceptibility screening of Orientia tsutsugamushi clinical isolates, using one timepoint and one concentration of antibiotics to considerably speed up the time to result. Methods: Growth, harvesting, multiplicity of infection (moi) and the day to determine the MICs were optimized using five O. tsutsugamushi reference strains [susceptible (Karp, Kato and Gilliam) and putatively resistant (AFC-3 and AFSC-4)], one clinical isolate (UT76) and one rodent isolate (TA763). Subsequently, the MICs of azithromycin, chloramphenicol and doxycycline for these strains and 51 clinical isolates including AFSC-7 were determined. An optimal concentration was calculated using the epidemiological cut-off value. Results: The conditions for O. tsutsugamushi infection, growth and harvesting were determined to be an moi of 100:1 and trypsinization with the peak growth on day 10. The resulting MICs were in line with previously published susceptibility data for all reference strains, except for Karp and AFSC-4, which showed azithromycin MICs of 0.0156 and 0.0313 mg/L, compared with 0.0078 and 0.0156 mg/L, respectively, in previous reports. The MIC of doxycycline for AFC-3 was 0.125 mg/L compared with >4 mg/L in earlier reports. The final single screening concentrations were identified as: azithromycin, 0.125 mg/L; chloramphenicol, 8 mg/L; and doxycycline, 1 mg/L. Conclusions: This simplified procedure facilitates the simultaneous screening of 48 isolates for actively monitoring potential resistance of this important fever pathogen, with an 8-fold throughput improvement over early methods. The data do not support the existence of doxycycline- and chloramphenicol-resistant scrub typhus.


Asunto(s)
Antibacterianos/farmacología , Ensayos Analíticos de Alto Rendimiento/métodos , Pruebas de Sensibilidad Microbiana/métodos , Orientia tsutsugamushi/efectos de los fármacos , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Animales , Humanos , Orientia tsutsugamushi/aislamiento & purificación , Roedores
18.
Brain Behav Immun ; 81: 545-559, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31325531

RESUMEN

Gulf War Illness (GWI), affecting 30% of veterans from the 1991 Gulf War (GW), is a multi-symptom illness with features similar to those of patients with autoimmune diseases. The objective of the current work is to determine if exposure to GW-related pesticides, such as permethrin (PER), activates peripheral and central nervous system (CNS) adaptive immune responses. In the current study, we focused on a PER metabolite, 3-phenoxybenzoic acid (3-PBA), as this is a common metabolite previously shown to form adducts with endogenous proteins. We observed the presence of 3-PBA and 3-PBA modified lysine of protein peptides in the brain, blood and liver of pyridostigmine bromide (PB) and  PER (PB+PER) exposed mice at acute and chronic post-exposure timepoints. We tested whether 3-PBA-haptenated albumin (3-PBA-albumin) can activate immune cells since it is known that chemically haptenated proteins can stimulate immune responses. We detected autoantibodies against 3-PBA-albumin in plasma from PB + PER exposed mice and veterans with GWI at chronic post-exposure timepoints. We also observed that in vitro treatment of blood with 3-PBA-albumin resulted in the activation of B- and T-helper lymphocytes and that these immune cells were also increased in blood of PB + PER exposed mice and veterans with GWI. These immune changes corresponded with elevated levels of infiltrating monocytes in the brain and blood of PB + PER exposed mice which coincided with alterations in the markers of blood-brain barrier disruption, brain macrophages and neuroinflammation. These studies suggest that pesticide exposure associated with GWI may have resulted in the activation of the peripheral and CNS adaptive immune responses, possibly contributing to an autoimmune-type phenotype in veterans with GWI.


Asunto(s)
Inmunidad Adaptativa/efectos de los fármacos , Permetrina/efectos adversos , Síndrome del Golfo Pérsico/metabolismo , Adulto , Animales , Benzoatos/análisis , Encéfalo/metabolismo , Sistema Nervioso Central/metabolismo , Modelos Animales de Enfermedad , Femenino , Guerra del Golfo , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Persona de Mediana Edad , Permetrina/metabolismo , Síndrome del Golfo Pérsico/fisiopatología , Bromuro de Piridostigmina/efectos adversos , Bromuro de Piridostigmina/metabolismo , Veteranos
19.
Malar J ; 18(1): 203, 2019 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-31221145

RESUMEN

BACKGROUND: As malaria elimination becomes a goal in malaria-endemic nations, questions of feasibility become critical. This article explores the potential challenges associated with this goal and future strategies for malaria elimination in the Greater Mekong Sub-region. METHODS: Thirty-two semi-structured interviews were conducted with policy makers (n = 17) and principal investigators (n = 15) selected based on their involvement in malaria prevention, control and elimination in the GMS. Interviews were audio-recorded and transcribed for qualitative content (thematic) analysis using QSR NVivo. RESULTS: All respondents described current malaria control and elimination strategies, such as case detection and management, prevention and strengthening of surveillance systems as critical and of equal priority. Aware of the emergence of multi-drug resistance in the GMS, researchers and policy makers outlined the need for additional elimination tools. As opposed to a centralized strategy, more targeted and tailored approaches to elimination were recommended. These included targeting endemic areas, consideration for local epidemiology and malaria species, and strengthening the peripheral health system. A decline in malaria transmission could lead to complacency amongst funders and policy makers resulting in a reduction or discontinuation of support for malaria elimination. Strong commitment of policymakers combined with strict monitoring and supervision by funders were considered pivotal to successful elimination programmes. CONCLUSION: Against a backdrop of increasing anti-malarial resistance and decreasing choices of anti-malarial regimens, policy makers and researchers stressed the urgency of finding new malaria elimination strategies. There was consensus that multi-pronged strategies and approaches are needed, that no single potential tool/strategy can be appropriate to all settings. Hence there is a need to customize malaria control and elimination strategies based on the better surveillance data.


Asunto(s)
Antimaláricos/farmacología , Erradicación de la Enfermedad/métodos , Resistencia a Múltiples Medicamentos , Malaria/prevención & control , Personal Administrativo/psicología , Asia Sudoriental , Humanos , Investigación Cualitativa , Encuestas y Cuestionarios
20.
J Enzyme Inhib Med Chem ; 34(1): 1474-1480, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31414611

RESUMEN

The discovery of allosteric modulators is a multi-disciplinary approach, which is time- and cost-intensive. High-throughput screening combined with novel computational tools can reduce these factors. Thus, we developed an enzyme activity assay, which can be included in the drug discovery work-flow subsequent to the in-silico library screening. While the in-silico screening yields in the identification of potential allosteric modulators, the developed in-vitro assay allows for the characterisation of them. Candida rugosa lipase (CRL), a glyceride hydrolysing enzyme, has been selected for the pilot development. The assay conditions were adjusted to CRL's properties including pH, temperature and substrate specificity for two different substrates. The optimised assay conditions were validated and were used to characterise Tropolone, which was identified as an allosteric modulator. In conclusion, the assay is a reliable, reproducible, and robust tool, which can be streamlined with in-silico screening and incorporated in an automated high-throughput screening workflow.


Asunto(s)
Lipasa/metabolismo , Miniaturización , Regulación Alostérica , Candida/enzimología , Cristalografía por Rayos X , Estabilidad de Enzimas , Ensayos Analíticos de Alto Rendimiento , Concentración de Iones de Hidrógeno , Técnicas In Vitro , Cinética , Límite de Detección , Lipasa/química , Reproducibilidad de los Resultados , Especificidad por Sustrato , Temperatura
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