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1.
Malar J ; 22(1): 345, 2023 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-37950227

RESUMEN

BACKGROUND: Seasonal malaria chemoprevention (SMC) using sulfadoxine-pyrimethamine plus amodiaquine (SP-AQ), is a community-based malaria preventive strategy commonly used in the Sahel region of sub-Saharan Africa. However, to date it has not been implemented in East Africa due to high SP resistance levels. This paper is a report on the implementation of SMC outside of the Sahel in an environment with a high level of presumed SP-resistance: five cycles of SMC using SPAQ were administered to children 3-59 months during a period of high malaria transmission (July-December 2019) in 21 villages in South Sudan. METHODS: A population-based SMC coverage survey was combined with a longitudinal time series analysis of health facility and community health data measured after each SMC cycle. SMC campaign effectiveness was assessed by Poisson model. SPAQ molecular resistance markers were additionally analysed from dried blood spots from malaria confirmed patients. RESULTS: Incidence of uncomplicated malaria was reduced from 6.6 per 100 to an average of 3.2 per 100 after SMC administration (mean reduction: 53%) and incidence of severe malaria showed a reduction from 21 per 10,000 before SMC campaign to a mean of 3.3 per 10,000 after each cycle (mean reduction: 84%) in the target group when compared to before the SMC campaign. The most prevalent molecular haplotype associated with SP resistance was the IRNGE haplotype (quintuple mutant, with 51I/59R/108N mutation in pfdhfr + 437G/540E in pfdhps). In contrast, there was a low frequency of AQ resistance markers and haplotypes resistant to both drugs combined (< 2%). CONCLUSIONS: The SMC campaign was effective and could be used as an additional preventive tool in seasonal malaria settings outside of the Sahel, especially in areas where access to health care is unstable. Malaria case load reduction was observed despite the high level of resistance to SP.


Asunto(s)
Antimaláricos , Malaria , Niño , Humanos , Antimaláricos/farmacología , Antimaláricos/uso terapéutico , Sudán del Sur , Estaciones del Año , Malaria/epidemiología , Malaria/prevención & control , Malaria/tratamiento farmacológico , Quimioprevención , Morbilidad , Resistencia a Medicamentos/genética
2.
Int J Mol Sci ; 24(3)2023 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-36768761

RESUMEN

The mineralocorticoid receptor (MR) belongs to the steroid receptor subfamily of nuclear receptors. MR is a transcription factor key in regulating blood pressure and mineral homeostasis. In addition, it plays an important role in a broad range of biological and pathological conditions, greatly expanding its interest as a pharmacological target. Non-steroidal MR antagonists (MRAs) are of particular interest to avoid side effects and achieve tissue-specific modulation of the receptor. The 1,4-dihydropyridine (1,4-DHP) ring has been identified as an appropriate scaffold to develop non-steroidal MRAs. We report the identification of a novel series of 1,4-DHP that has been guided by structure-based drug design, focusing on the less explored DHP position 2. Interestingly, substituents at this position might interfere with MR helix H12 disposition, which is essential for the recruitment of co-regulators. Several of the newly synthesized 1,4-DHPs show interesting properties as MRAs and have a good selectivity profile. These 1,4-DHPs promote MR nuclear translocation with less efficiency than the natural agonist aldosterone, which explains, at least in part, its antagonist character. Molecular dynamic studies are suggestive of several derivatives interfering with the disposition of H12 in the agonist-associated conformation, and thus, they might stabilize an MR conformation unable to recruit co-activators.


Asunto(s)
Dihidropiridinas , Antagonistas de Receptores de Mineralocorticoides , Antagonistas de Receptores de Mineralocorticoides/farmacología , Antagonistas de Receptores de Mineralocorticoides/uso terapéutico , Receptores de Mineralocorticoides , Dihidropiridinas/farmacología , Dihidropiridinas/química , Aldosterona/farmacología , Bloqueadores de los Canales de Calcio/uso terapéutico
3.
Environ Monit Assess ; 195(9): 1049, 2023 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-37589757

RESUMEN

Coastal lagoons are vulnerable to eutrophication processes. In this study, we evaluate the eutrophication process in the restricted, arid subtropical Tóbari coastal lagoon, located in the eastern coast of the Gulf of California, where the main source of nutrient inputs and other pollutants is agricultural wastewater from the Yaqui Valley. The Assessment of Estuarine Trophic Status (ASSETS) model and the Trophic State Index (TRIX) were used to evaluate eutrophication. Overall, ASSETS showed that the Tóbari lagoon has a moderate eutrophication process, with seasonal symptoms of hypoxia, increased phytoplankton biomass, dominance of macroalgae (indicative of nutrient enrichment), and blooms development of potentially harmful algae species. The TRIX showed that the lagoon is mesotrophic most of the year. Challenges of environmental management detected correspond to reducing the input of nutrients and others contaminants from anthropic sources: agriculture, shrimp farming, livestock, and urban zones.


Asunto(s)
Conservación de los Recursos Naturales , Monitoreo del Ambiente , California , Agricultura , Eutrofización
4.
Emerg Infect Dis ; 28(2): 453-456, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35076006

RESUMEN

Transplacental transmission of Zika virus has been reported during all trimesters of pregnancy and might lead to central nervous system anomalies, including microcephaly. We report 3 cases of perinatal Zika infection identified during the epidemic in Colombia and provide detailed descriptions of clinical features, diagnosis, and neurodevelopmental outcome at 18 months of age (corrected).


Asunto(s)
Microcefalia , Complicaciones Infecciosas del Embarazo , Infección por el Virus Zika , Virus Zika , Colombia/epidemiología , Femenino , Humanos , Lactante , Transmisión Vertical de Enfermedad Infecciosa , Microcefalia/epidemiología , Microcefalia/etiología , Embarazo , Infección por el Virus Zika/diagnóstico , Infección por el Virus Zika/epidemiología
5.
Gastroenterology ; 160(4): 1106-1117.e3, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33220252

RESUMEN

BACKGROUND & AIMS: Helicobacter pylori eradication and endoscopic surveillance of gastric precancerous lesions are strategies to reduce gastric cancer (GC) risk. To our knowledge, this study is the longest prospective cohort of an H pylori eradication trial in a Hispanic population. METHODS: A total of 800 adults with precancerous lesions were randomized to anti-H pylori treatment or placebo. Gastric biopsy samples taken at baseline and 3, 6, 12, 16, and 20 years were assessed by our Correa histopathology score. A generalized linear mixed model with a participant-level random intercept was used to estimate the effect of H pylori status on the score over time. Logistic regression models were used to estimate progression by baseline diagnosis and to estimate GC risk by intestinal metaplasia (IM) subtype and anatomic location. RESULTS: Overall, 356 individuals completed 20 years of follow-up. Anti-H pylori therapy (intention-to-treat) reduced progression of the Correa score (odds ratio [OR], 0.59; 95% confidence interval [CI], 0.38-0.93). H pylori-negative status had a beneficial effect on the score over time (P = .036). Among individuals with IM (including indefinite for dysplasia) at baseline, incidence rates per 100 person-years were 1.09 (95% CI, 0.85-1.33) for low-grade/high-grade dysplasia and 0.14 (95% CI, 0.06-0.22) for GC. Incomplete-type (vs complete-type) IM at baseline presented higher GC risk (OR, 13.4; 95% CI, 1.8-103.8). Individuals with corpus (vs antrum-restricted) IM showed an OR of 2.1 (95% CI, 0.7-6.6) for GC. CONCLUSIONS: In a high-GC-risk Hispanic population, anti-H pylori therapy had a long-term beneficial effect against histologic progression. Incomplete IM is a strong predictor of GC risk.


Asunto(s)
Antibacterianos/uso terapéutico , Mucosa Gástrica/patología , Infecciones por Helicobacter/tratamiento farmacológico , Lesiones Precancerosas/epidemiología , Neoplasias Gástricas/prevención & control , Adulto , Anciano , Biopsia , Colombia/epidemiología , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Mucosa Gástrica/diagnóstico por imagen , Mucosa Gástrica/microbiología , Gastroscopía/estadística & datos numéricos , Infecciones por Helicobacter/microbiología , Infecciones por Helicobacter/patología , Helicobacter pylori/aislamiento & purificación , Humanos , Incidencia , Masculino , Metaplasia/diagnóstico , Metaplasia/epidemiología , Metaplasia/microbiología , Metaplasia/patología , Persona de Mediana Edad , Lesiones Precancerosas/diagnóstico , Lesiones Precancerosas/microbiología , Lesiones Precancerosas/patología , Estudios Prospectivos , Factores de Riesgo , Neoplasias Gástricas/epidemiología , Neoplasias Gástricas/microbiología , Neoplasias Gástricas/patología , Resultado del Tratamiento
6.
Malar J ; 21(1): 287, 2022 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-36209103

RESUMEN

BACKGROUND: Although rapid diagnostic tests (RDTs) play a key role in malaria-control strategies, their efficacy has been threatened by deletion and genetic variability of the genes pfhrp2/3. This study aims to characterize the deletion, genetic patterns and diversity of these genes and their implication for malaria RDT effectiveness, as well as their genetic evolution in the Amhara region of Ethiopia. METHODS: The study included 354 isolates from symptomatic patients from the Amhara region of Ethiopia who tested positive by microscopy. Exon 1-2 and exon 2 of genes pfhrp2 and -3 were amplified, and exon 2 was sequenced to analyse the genetic diversity, phylogenetic relationship and epitope availability. RESULTS: The deletion frequency in exon 1-2 and exon 2 was 22 and 4.6% for pfhrp2, and 68 and 18% for pfhrp3, respectively. Double deletion frequency for pfhrp2 and pfhrp3 was 1.4%. High genetic diversity, lack of clustering by phylogenetic analysis and evidence of positive selection suggested a diversifying selection for both genes. The amino-acid sequences, classified into different haplotypes, varied widely in terms of frequency of repeats, with novel amino-acid changes. Aminoacidic repetition type 2 and type 7 were the most frequent in all the sequences. The most frequent epitopes among protein sequences were those recognized by MAbs 3A4 and C1-13. CONCLUSION: Deletions and high amino acidic variation in pfhrp2 and pfhrp3 suggest their possible impact on RDT use in the Amhara region, and the high genetic diversity of these genes could be associated with a diversifying selection in Ethiopia. Surveillance of these genes is, therefore, essential to ensure the effectiveness of public health interventions in this region.


Asunto(s)
Malaria Falciparum , Malaria , Antígenos de Protozoos/genética , Pruebas Diagnósticas de Rutina , Epítopos , Etiopía , Eliminación de Gen , Humanos , Malaria/genética , Malaria Falciparum/epidemiología , Filogenia , Plasmodium falciparum/genética , Proteínas Protozoarias/genética
7.
Acta Obstet Gynecol Scand ; 101(2): 221-231, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34904224

RESUMEN

INTRODUCTION: In October 2015, an epidemic of Zika began in Colombia's geographic areas with a high population of mosquitoes of the genus Aedes. We aimed to describe the fetal brain ultrasound findings in pregnant women with active symptoms or a history of symptoms suggestive of Zika virus (ZIKV) infection. MATERIAL AND METHODS: Eligible pregnant women were tested with reverse transcriptase-polymerase chain reaction (RT-PCR) for ZIKV and followed prospectively using detailed anatomic ultrasound and transvaginal neurosonography to detect structural anomalies of the fetal central nervous system (CNS). RESULTS: A total of 115 symptomatic women with a positive ZIKV RT-PCR and 55 with a negative ZIKV RT-PCR were enrolled in the study; CNS compromise of the fetus occurred in 22% and 17%, respectively (p = 0.255). Callosal dysgenesis (14.5%) was the most frequent anomaly of the CNS, followed by microcephaly (13.6%) and neuronal migration disorders (8.3%). When symptomatic ZIKV RT-PCR-positive women were categorized by trimester of infection, CNS anomalies were present in 40% of first-trimester infections, compared with 21% and 7% in second- and third-trimester infections (p = 0.002). CNS anomalies were also more severe in first-trimester-infected fetuses than in second- and third-trimester-infected fetuses. The high prevalence of CNS anomalies in fetuses of symptomatic ZIKV RT-PCR negative women suggests a high rate of false-negative cases and an even higher prevalence of CNS anomalies than observed in this study. CONCLUSIONS: The prevalence of fetal CNS anomalies was higher than previously reported in the literature for both symptomatic RT-PCR-positive and -negative pregnant women. Corpus callosum anomalies, microcephaly, neuronal migration disorders, and brain parenchymal hyperechogenicities were the most frequent CNS anomalies detected. In addition, CNS anomalies were more frequent and severe in infected fetuses during the first trimester of pregnancy than during the second or third trimester.


Asunto(s)
Sistema Nervioso Central/anomalías , Microcefalia/epidemiología , Complicaciones Infecciosas del Embarazo , Ultrasonografía Prenatal , Infección por el Virus Zika , Virus Zika/aislamiento & purificación , Anomalías Múltiples/diagnóstico por imagen , Anomalías Múltiples/epidemiología , Anomalías Múltiples/etiología , Adolescente , Adulto , Sistema Nervioso Central/diagnóstico por imagen , Estudios de Cohortes , Colombia/epidemiología , Femenino , Edad Gestacional , Humanos , Microcefalia/diagnóstico por imagen , Microcefalia/etiología , Embarazo , Trimestres del Embarazo , Prevalencia , Estudios Prospectivos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Adulto Joven , Virus Zika/genética
8.
Salud Publica Mex ; 64(3, may-jun): 243-248, 2022 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-36130390

RESUMEN

OBJECTIVE: To describe the humoral response in a cohort with mild and asymptomatic SARS-CoV-2 infection previ-ously identified in a community-based serological survey. MATERIALS AND METHODS: This study was an observational follow up of 193 subjects previously identified with positive anti-SARS-CoV-2 antibodies invited for a second test 112 days after the first sampling. All completed a standardized electronic questionnaire. IgM/IgG antibodies were determined using a qualitative IgM/IgG chemiluminescent immunoassay. RESULTS: Among the 193 eligible subjects, a total of 174 (90%) attended the follow-up visit, and their serum samples were tested. Of the samples, 171 (98.3%) were still positive, and 3 (1.7%) were negative. Also, the cut-off index (COI) value of the immunoassay significantly increased from the first to the second test (P <0.001). CONCLUSIONS: Our findings support a sustained humoral response in individuals with mild and asymptomatic SARS-CoV-2 infection up to 112 days after a positive serologic baseline test, accompanied by increasing antibody titers.


Asunto(s)
COVID-19 , SARS-CoV-2 , Anticuerpos Antivirales , Estudios de Seguimiento , Humanos , Inmunoglobulina G , Inmunoglobulina M
9.
Malar J ; 20(1): 463, 2021 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-34906159

RESUMEN

BACKGROUND: Malaria is one of the deadliest diseases in the world, particularly in Africa. As such, resistance to anti-malarial drugs is one of the most important problems in terms of global malaria control. This study assesses the evolution of the different resistance markers over time and the possible influence of interventions and treatment changes that have been made in Equatorial Guinea. METHODS: A total of 1223 biological samples obtained in the period 1999 to 2019 were included in the study. Screening for mutations in the pfdhfr, pfdhps, pfmdr1, and pfcrt genes was carried out by nested PCR and restriction-fragment length polymorphisms (RFLPs), and the study of pfk13 genes was carried out by nested PCR, followed by sequencing to determine the presence of mutations. RESULTS: The partially and fully resistant haplotypes (pfdhfr + pfdhps) were found to increase over time. Moreover, in 2019, the fully resistant haplotype was found to be increasing, although its super-resistant counterpart remains much less prevalent. A continued decline in pfmdr1 and pfcrt gene mutations over time was also found. The number of mutations detected in pfk13 has increased since 2008, when artemisinin-based combination therapy (ACT) were first introduced, with more mutations being observed in 2019, with two synonymous and five non-synonymous mutations being detected, although these are not related to resistance to ACT. In addition, the non-synonymous A578S mutation, which is the most frequent on the African continent, was detected in 2013, although not in the following years. CONCLUSIONS: Withdrawal of the use of chloroquine (CQ) as a treatment in Equatorial Guinea has been shown to be effective over time, as wild-type parasite populations outnumber mutant populations. The upward trend observed in sulfadoxine-pyrimethamine (SP) resistance markers suggest its misuse, either alone or in combination with artesunate (AS) or amodiaquine (AQ), in some areas of the country, as was found in a previous study conducted by this group, which allows selective pressure from SP to continue. Single nucleotide polymorphisms (SNPs) 540E and 581G do not exceed the limit of 50 and 10%, respectively, thus meaning that SP is still effective as an intermittent preventive treatment (IPT) in this country. As for the pfk13 gene, no mutations have been detected in relation to resistance to ACT. However, in 2019 there is a greater accumulation of non-synonymous mutations compared to years prior to 2008.


Asunto(s)
Antimaláricos/farmacología , Resistencia a Medicamentos/genética , Genotipo , Plasmodium falciparum/genética , Guinea Ecuatorial , Evolución Molecular , Plasmodium falciparum/efectos de los fármacos , Polimorfismo de Nucleótido Simple
10.
Malar J ; 20(1): 275, 2021 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-34158055

RESUMEN

BACKGROUND: Artesunate-amodiaquine (ASAQ) and artemether-lumefantrine (AL) are the currently recommended first- and second-line therapies for uncomplicated Plasmodium falciparum infections in Equatorial Guinea. This study was designed to evaluate the efficacy of these artemisinin-based combinations and detect mutations in P. falciparum kelch13-propeller domain gene (Pfkelch13). METHODS: A single-arm prospective study evaluating the efficacy of ASAQ and AL at three sites: Malabo, Bata and Ebebiyin was conducted between August 2017 and July 2018. Febrile children aged six months to 10 years with confirmed uncomplicated P. falciparum infection and other inclusion criteria were sequentially enrolled first in ASAQ and then in AL at each site, and followed up for 28 days. Clinical and parasitological parameters were assessed. The primary endpoint was PCR-adjusted adequate clinical and parasitological response (ACPR). Samples on day-0 were analysed for mutations in Pfkelch13 gene. RESULTS: A total 264 and 226 patients were enrolled in the ASAQ and AL treatment groups, respectively. Based on per-protocol analysis, PCR-adjusted cure rates of 98.6% to 100% and 92.4% to 100% were observed in patients treated with ASAQ and AL, respectively. All study children in both treatment groups were free of parasitaemia by day-3. Of the 476 samples with interpretable results, only three samples carried non-synonymous Pfkelch13 mutations (E433D and A578S), and none of them is the known markers associated with artemisinin resistance. CONCLUSION: The study confirmed high efficacy of ASAQ and AL for the treatment of uncomplicated falciparum infections as well as the absence of delayed parasite clearance and Pfkelch13 mutations associated with artemisinin resistance. Continued monitoring of the efficacy of these artemisinin-based combinations, at least every two years, along with molecular markers associated with artemisinin and partner drug resistance is imperative to inform national malaria treatment policy and detect resistant parasites early. Trial registration ACTRN12617000456358, Registered 28 March 2017; http://www.anzctr.org.au/trial/MyTrial.aspx.


Asunto(s)
Amodiaquina/administración & dosificación , Combinación Arteméter y Lumefantrina/administración & dosificación , Artemisininas/administración & dosificación , Plasmodium falciparum/efectos de los fármacos , Polimorfismo Genético , Proteínas Protozoarias/genética , Niño , Preescolar , Combinación de Medicamentos , Guinea Ecuatorial , Femenino , Humanos , Lactante , Masculino , Plasmodium falciparum/genética , Estudios Prospectivos
11.
Sensors (Basel) ; 21(2)2021 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-33435294

RESUMEN

Research on autonomous cars has become one of the main research paths in the automotive industry, with many critical issues that remain to be explored while considering the overall methodology and its practical applicability. In this paper, we present an industrial experience in which we build a complete autonomous driving system, from the sensor units to the car control equipment, and we describe its adoption and testing phase on the field. We report how we organize data fusion and map manipulation to represent the required reality. We focus on the communication and synchronization issues between the data-fusion device and the path-planner, between the CPU and the GPU units, and among different CUDA kernels implementing the core local planner module. In these frameworks, we propose simple representation strategies and approximation techniques which guarantee almost no penalty in terms of accuracy and large savings in terms of memory occupation and memory transfer times. We show how we adopt a recent implementation on parallel many-core devices, such as CUDA-based GPGPU, to reduce the computational burden of rapidly exploring random trees to explore the state space along with a given reference path. We report on our use of the controller and the vehicle simulator. We run experiments on several real scenarios, and we report the paths generated with the different settings, with their relative errors and computation times. We prove that our approach can generate reasonable paths on a multitude of standard maneuvers in real time.

12.
Gac Med Mex ; 157(5): 502-507, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35104264

RESUMEN

BACKGROUND: Altered cortisol levels have been associated with an increase in mortality and a decrease in health-related quality of life in patients with chronic kidney disease (CKD); however, adrenal response to adrenocorticotropic hormone (ACTH) stimulation test has not been evaluated in patients with stage 3a to 5 CKD with and without renal replacement therapy (RRT). OBJECTIVE: To evaluate adrenal function in patients with CKD. MATERIALS AND METHODS: Adults with CKD underwent a low-dose cosyntropin stimulation test (1 µg synthetic ACTH), with serum cortisol levels being measured at 0, +30 and +60 minutes post-test. RESULTS: Sixty participants with stage 3, 4 and 5 CKD (with and without RRT) were included. None of the patients had adrenal insufficiency (AI). The correlation observed between cortisol concentration at baseline and 30 minutes and 1 hour after stimulation and glomerular filtration rate (GFR) was negative and statistically significant (r: -0.39 [p = 0.002], r: -0.363 [p = 0.004], r: -0.4 [p = 0.002], respectively). CONCLUSION: Since CKD early stages, cortisol levels increase as GFR decreases. Therefore, we conclude that systematic screening for AI is not necessary in CKD patients.


ANTECEDENTES: Niveles alterados de cortisol se han asociado a un incremento en la mortalidad y disminución en la calidad de vida en pacientes con enfermedad renal crónica (ERC), sin embargo, la respuesta adrenal a la prueba de estimulación con adrenocorticotropina (ACTH) no ha sido evaluada en pacientes con ERC etapas 3a a 5 con y sin terapia de reemplazo renal (TRR). OBJETIVO: Evaluar la función adrenal de pacientes con ERC. MATERIALES Y MÉTODOS: Adultos con ERC se sometieron a una prueba de estimulación con cosintropina a dosis baja (1 mg de ACTH sintética) y se midieron los niveles séricos de cortisol a los 0, +30 y +60 minutos postestimulación. RESULTADOS: 60 participantes con ERC en etapas 3, 4 y 5 (con y sin TRR) fueron incluidos. Ninguno de los pacientes presentó insuficiencia adrenal (IA). La correlación observada entre la concentración basal, a los 30 minutos y 1 hora de cortisol postestimulación y la tasa de filtrado glomerular (TFG) fue negativa y estadísticamente significativa (r: ­0.39 [p = 0.002], r: ­0.363 [p = 0.004], r: ­0.4 [p = 0.002], respectivamente). CONCLUSIÓN: Desde etapas tempranas de la ERC los niveles de cortisol se incrementan a medida que la TFG disminuye. Concluimos que no es necesario un tamizaje sistemático para detectar IA en pacientes con ERC.


Asunto(s)
Calidad de Vida , Insuficiencia Renal Crónica , Hormona Adrenocorticotrópica , Cosintropina , Tasa de Filtración Glomerular , Humanos
13.
Appl Environ Microbiol ; 86(20)2020 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-32801174

RESUMEN

Cr(VI) is mutagenic and teratogenic and considered an environmental pollutant of increasing concern. The use of microbial enzymes that convert this ion into its less toxic reduced insoluble form, Cr(III), represents a valuable bioremediation strategy. In this study, we examined the Bacillus subtilis YhdA enzyme, which belongs to the family of NADPH-dependent flavin mononucleotide oxide reductases and possesses azo-reductase activity as a factor that upon overexpression confers protection on B. subtilis from the cytotoxic effects promoted by Cr(VI) and counteracts the mutagenic effects of the reactive oxygen species (ROS)-promoted lesion 8-OxoG. Further, our in vitro assays unveiled catalytic and biochemical properties of biotechnological relevance in YhdA; a pure recombinant His10-YhdA protein efficiently catalyzed the reduction of Cr(VI) employing NADPH as a cofactor. The activity of the pure oxidoreductase YhdA was optimal at 30°C and at pH 7.5 and displayed Km and Vmax values of 7.26 mM and 26.8 µmol·min-1·mg-1 for Cr(VI), respectively. Therefore, YhdA can be used for efficient bioremediation of Cr(VI) and counteracts the cytotoxic and genotoxic effects of oxygen radicals induced by intracellular factors and those generated during reduction of hexavalent chromium.IMPORTANCE Here, we report that the bacterial flavin mononucleotide/NADPH-dependent oxidoreductase YhdA, widely distributed among Gram-positive bacilli, conferred protection to cells from the cytotoxic effects of Cr(VI) and prevented the hypermutagenesis exhibited by a MutT/MutM/MutY-deficient strain. Additionally, a purified recombinant His10-YhdA protein displayed a strong NADPH-dependent chromate reductase activity. Therefore, we postulate that in bacterial cells, YhdA counteracts the cytotoxic and genotoxic effects of intracellular and extracellular inducers of oxygen radicals, including those caused by hexavalent chromium.


Asunto(s)
Bacillus subtilis/efectos de los fármacos , Bacillus subtilis/fisiología , Proteínas Bacterianas/metabolismo , Cromo/toxicidad , FMN Reductasa/metabolismo , Bacillus subtilis/enzimología , Bacillus subtilis/genética , Proteínas Bacterianas/química , FMN Reductasa/química
14.
Malar J ; 19(1): 99, 2020 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-32122352

RESUMEN

BACKGROUND: The World Health Organization (WHO) recommends rapid diagnostic tests (RDTs) as a good alternative malaria-diagnosis method in remote parts of sub-Saharan Africa. The majority of commercial RDTs currently available detect the Plasmodium falciparum protein histidine-rich protein 2 (PfHRP2). There have also been recent reports of pfhrp2 gene deletions being found in parasites collected from several African countries. The WHO has concluded that lacking the pfhrp2 gene must be monitored in Africa. The purpose of the study was to analyse why the samples that were positive by PCR were negative by RDTs and, therefore, to determine whether there have been deletions in the pfhrp2 and/or pfhrp3 genes. METHODS: Malaria NM-PCR was carried out on all the samples collected in the field. A group of 128 samples was positive by PCR but negative by RDT; these samples were classified as RDT false-negatives. PCR was carried out for exon2 of pfhrp2 and pfhrp3 genes to detect the presence or absence of these two genes. Frequencies with 95% confidence intervals (CIs) were used for prevalence estimates. Associations were assessed by the Chi square test or Fisher´s exact test. The level of significance was set at p ≤ 0.05. Statistical analyses were performed using the software package SPSSv.15.0. RESULTS: After PCR, 81 samples were identified (4.7%, 95% CI 3.8-5.8) which had deletion in both genes, pfhrp2 and pfhrp3. Overall, however, 11 samples (0.6%, 95% CI 0.36-1.14) had deletion only in pfhrp2 but not in pfhrp3, and 15 (0.9%, 95% CI 0.6-1.5) presented with deletion only in pfhrp3 but not in pfhrp2. Considering the pfhrp2 gene separately, within the total of 1724 samples, 92 (5.3%, 95% CI 4.37-6.5) had evidence of deletion. CONCLUSION: The present study provides the first evidence of deletion in the pfhrp2 and pfhrp3 genes in P. falciparum isolates from Equatorial Guinea. However, larger studies across different regions within the country and across different seasonal profiles are needed to determine the full extent of pfhrp2 and pfhrp3 deletion. It is strongly recommended to implement an active surveillance programme in order to detect any increases in pfhrp2 and pfhrp3 deletion frequencies.


Asunto(s)
Antígenos de Protozoos/genética , Eliminación de Gen , Plasmodium falciparum/genética , Proteínas Protozoarias/genética , Pruebas Diagnósticas de Rutina , Guinea Ecuatorial/epidemiología , Reacciones Falso Negativas , Genes Protozoarios , Microscopía , Reacción en Cadena de la Polimerasa Multiplex , Prevalencia
15.
Gac Med Mex ; 155(2): 149-155, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31056615

RESUMEN

INTRODUCTION: Concepts related to end-of-life decisions, such as euthanasia, palliative care, advance directives and therapeutic obstinacy, are poorly understood by the general population, which, when facing a terminal situation, is not prepared to choose the best option. OBJECTIVE: Pilot study (n = 544) to find out what the open population understands about terms used in end-of-life situations in four cities of the Mexican Republic. METHOD: Survey via Internet with 18 questions about different terms. It was a descriptive, cross-sectional study. Statistical analysis was carried out. RESULTS: People older than 18 years who were not engaged in health-related professional activities were selected. CONCLUSIONS: Most terms related to end-of-life decisions were found not to be interesting to or understood by a part of the population. The least recognized term was therapeutic obstinacy (62.8%), and the most widely known, palliative care (91%); there was confusion between the terms euthanasia and assisted suicide (47.8%). Age and education level had more influence in the results, than other demographic variables.


INTRODUCCIÓN: Conceptos relacionados con las decisiones que se toman al final de la vida, como eutanasia, cuidados paliativos, voluntad anticipada y obstinación terapéutica son poco comprendidos por la población en general, que en el momento de enfrentar una situación terminal no está preparada para elegir la mejor opción. OBJETIVO: Estudio piloto (n = 544) para conocer lo que la población abierta entiende acerca de términos utilizados al final de la vida en cuatro ciudades de la república mexicana. MÉTODO: Encuesta vía internet de 18 preguntas sobre los distintos términos. Se trató de un estudio descriptivo, transversal, con análisis estadístico. RESULTADOS: Se eligieron personas mayores de 18 años que no trabajaran en profesiones relacionadas con la salud. CONCLUSIONES: La mayoría de los términos del final de la vida no interesaron ni fueron entendidos por parte de la población. El término menos reconocido fue la obstinación terapéutica (62.8 %) y el más conocido, cuidados paliativos (91 %); se confunden los términos eutanasia y suicidio asistido (47.8 %). La edad y escolaridad resultaron de mayor influencia en los resultados, que las otras variables demográficas.


Asunto(s)
Conocimientos, Actitudes y Práctica en Salud , Cuidados Paliativos/psicología , Cuidado Terminal/psicología , Adolescente , Adulto , Directivas Anticipadas/psicología , Directivas Anticipadas/estadística & datos numéricos , Factores de Edad , Anciano , Estudios Transversales , Escolaridad , Eutanasia/psicología , Eutanasia/estadística & datos numéricos , Femenino , Humanos , Masculino , México , Persona de Mediana Edad , Cuidados Paliativos/estadística & datos numéricos , Proyectos Piloto , Suicidio Asistido/psicología , Suicidio Asistido/estadística & datos numéricos , Encuestas y Cuestionarios , Cuidado Terminal/estadística & datos numéricos , Adulto Joven
16.
FASEB J ; 31(6): 2267-2275, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28188174

RESUMEN

Brain atrophy is a common feature of numerous neurologic diseases in which the role of neuroinflammation remains ill-defined. In this study, we evaluated the contribution of major histocompatibility complex class I molecules to brain atrophy in Theiler's murine encephalomyelitis virus (TMEV)-infected transgenic FVB mice that express the Db class I molecule. FVB/Db and wild-type FVB mice were evaluated for changes in neuroinflammation, virus clearance, neuropathology, and development of brain atrophy via T2-weighted MRI and subsequent 3-dimensional volumetric analysis. Significant brain atrophy and hippocampal neuronal loss were observed in TMEV-infected FVB/Db mice, but not in wild-type FVB mice. Brain atrophy was observed at 1 mo postinfection and persisted through the 4-mo observation period. Of importance, virus-infected FVB/Db mice elicited a strong CD8 T-cell response toward the immunodominant Db-restricted TMEV-derived peptide, VP2121-130, and cleared TMEV from the CNS. In addition, immunofluorescence revealed CD8 T cells near virus-infected neurons; therefore, we hypothesize that class I restricted CD8 T-cell responses promote development of brain atrophy. This model provides an opportunity to analyze the contribution of immune cells to brain atrophy in a system where persistent virus infection and demyelination are not factors in long-term neuropathology.-Huseby Kelcher, A. M., Atanga, P. A., Gamez, J. D., Cumba Garcia, L. M., Teclaw, S. J., Pavelko, K. D., Macura, S. I., Johnson. A. J. Brain atrophy in picornavirus-infected FVB mice is dependent on the H-2Db class I molecule.


Asunto(s)
Encefalopatías/virología , Encéfalo/patología , Genes MHC Clase I/genética , Infecciones por Picornaviridae/patología , Theilovirus , Animales , Atrofia , Encéfalo/virología , Linfocitos T CD8-positivos/fisiología , Modelos Animales de Enfermedad , Regulación de la Expresión Génica , Ratones , Ratones Endogámicos , Ratones Transgénicos , Neuronas/virología , Infecciones por Picornaviridae/inmunología , Carga Viral
17.
Malar J ; 17(1): 333, 2018 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-30223852

RESUMEN

BACKGROUND: Malaria in Equatorial Guinea remains a major public health problem. The country is a holo-endemic area with a year-round transmission pattern. In 2016, the prevalence of malaria was 12.09% and malaria caused 15% of deaths among children under 5 years. In the Continental Region, 95.2% of malaria infections were Plasmodium falciparum, 9.5% Plasmodium vivax, and eight cases mixed infection in 2011. The main strategy for malaria control is quick and accurate diagnosis followed by effective treatment. Early and accurate diagnosis of malaria is essential for both effective disease management and malaria surveillance. The quality of malaria diagnosis is important in all settings, as misdiagnosis can result in significant morbidity and mortality. Microscopy and RDTs are the primary choices for diagnosing malaria in the field. However, false-negative results may delay treatment and increase the number of persons capable of infecting mosquitoes in the community. The present study analysed the performance of microscopy and RDTs, the two main techniques used in Equatorial Guinea for the diagnosis of malaria, compared to semi-nested multiplex PCR (SnM-PCR). RESULTS: A total of 1724 samples tested by microscopy, RDT, and SnM-PCR were analysed. Among the negative samples detected by microscopy, 335 (19.4%) were false negatives. On the other hand, the negative samples detected by RDT, 128 (13.3%) were false negatives based on PCR. This finding is important, especially since it is a group of patients who did not receive antimalarial treatment. CONCLUSIONS: Owing to the high number of false negatives in microscopy, it is necessary to reinforce training in microscopy, the "Gold Standard" in endemic areas. A network of reference centres could potentially support ongoing diagnostic and control efforts made by malaria control programmes in the long term, as the National Centre of Tropical Medicine currently supports the National Programme against Malaria of Equatorial Guinea to perform all of the molecular studies necessary for disease control. Taking into account the results obtained with the RDTs, an exhaustive study of the deletion of the hrp2 gene must be done in EG to help choose the correct RDT for this area.


Asunto(s)
Cromatografía de Afinidad/métodos , Pruebas Diagnósticas de Rutina/métodos , Malaria Falciparum/diagnóstico , Malaria Vivax/diagnóstico , Microscopía/métodos , Reacción en Cadena de la Polimerasa/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Animales , Niño , Preescolar , Estudios Transversales , Guinea Ecuatorial , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Adulto Joven
18.
Molecules ; 23(12)2018 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-30513599

RESUMEN

Antigenic fractions of 100, 50, 37, and 28 kDa obtained through the SDS-PAGE method that were more frequently recognized by anti-Coccidioides antibodies in the sera of coccidioidomycosis patients were selected using western blotting. Subsequently, these bands were sequenced, and the obtained proteins were analysed by BLAST to choose peptides specific for Coccidioides spp. from among the shared aligned sequences of related fungi. A peptide specific for C. immitis was selected from the "GPI anchored serine-threonine rich protein OS C. immitis", while from the "uncharacterized protein of C. immitis", we selected a peptide for C. immitis and C. posadasii. These proteins arose from the 100 kDa antigenic fraction. From the protein "fatty acid amide hydrolase 1 of C. posadasii" that was identified from the 50 kDa antigenic fraction, a peptide was selected that recognized C. immitis and C. posadasii. In addition, the analysis of all the peptides (353) of each of the assembled proteins showed that only 35 had 100% identity with proteins of C. immitis and C. posadasii, one had 100% identity with only C. immitis, and one had 100% identity with only C. posadasii. These peptides can be used as diagnostic reagents, vaccines, and antifungals.


Asunto(s)
Antígenos Fúngicos/aislamiento & purificación , Western Blotting/métodos , Coccidioides/inmunología , Coccidioidomicosis/sangre , Coccidioidomicosis/inmunología , Electroforesis en Gel de Poliacrilamida/métodos , Péptidos/aislamiento & purificación , Adulto , Anciano , Secuencia de Aminoácidos , Antígenos Fúngicos/química , Niño , Coccidioides/aislamiento & purificación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Péptidos/química , Adulto Joven
19.
Malar J ; 16(1): 28, 2017 01 13.
Artículo en Inglés | MEDLINE | ID: mdl-28086777

RESUMEN

BACKGROUND: The emergence of drug resistance in Plasmodium falciparum has been a major contributor to the global burden of malaria. Drug resistance complicates treatment, and it is one of the most important problems in malaria control. This study assessed the level of mutations in P. falciparum genes, pfdhfr, pfdhps, pfmdr1, and pfcrt, related to resistance to different anti-malarial drugs, in the Continental Region of Equatorial Guinea, after 8 years of implementing artesunate combination therapies as the first-line treatment. RESULTS: A triple mutant of pfdhfr (51I/59R/108N), which conferred resistance to sulfadoxine/pyrimethamine (SP), was found in 78% of samples from rural settings; its frequency was significantly different between urban and rural settings (p = 0.007). The 164L mutation was detected for the first time in this area, in rural settings (1.4%). We also identified three classes of previously described mutants and their frequencies: the partially resistant (pfdhfr 51I/59R/108N + pfdhps 437G), found at 54% (95% CI 47.75-60.25); the fully resistant (pfdhfr 51I/59R/108N + pfdhps 437G/540E), found at 28% (95% CI 7.07-14.93); and the super resistant (pfdhfr 51I/59R/108N + pfdhps 437G/540E/581G), found at 6% (95% CI 0.48-4.32). A double mutation in pfmdr1 (86Y + 1246Y) was detected at 2% (95% CI 0.24-3.76) frequency, distributed in both urban and rural samples. A combination of single mutations in the pfmdr1 and pfcrt genes (86Y + 76T), which was related to resistance to chloroquine and amodiaquine, was detected in 22% (95% CI 16.8-27.2) of samples from the area. CONCLUSIONS: The high level of mutations detected in P. falciparum genes related to SP resistance could be linked to the unsuccessful withdrawal of SP treatment in this area. Drug resistance can reduce the efficacy of intermittent prophylactic treatment with SP for children under 5 years old and for pregnant women. Although a high number of mutations was detected, the efficacy of the first-line treatment, artemisinin/amodiaquine, was not affected. To avoid increases in the numbers, occurrence, and spread of mutations, and to protect the population, the Ministry of Health should ensure that health centres and hospitals are supplied with appropriate first-line treatments for malaria.


Asunto(s)
Antimaláricos/farmacología , Dihidropteroato Sintasa/genética , Resistencia a Medicamentos , Proteínas de Transporte de Membrana/genética , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/genética , Plasmodium falciparum/efectos de los fármacos , Proteínas Protozoarias/genética , Tetrahidrofolato Deshidrogenasa/genética , Estudios Transversales , Combinación de Medicamentos , Guinea Ecuatorial , Frecuencia de los Genes , Genotipo , Humanos , Mutación , Plasmodium falciparum/enzimología , Plasmodium falciparum/genética , Plasmodium falciparum/aislamiento & purificación , Pirimetamina/farmacología , Sulfadoxina/farmacología
20.
J Bacteriol ; 198(24): 3345-3354, 2016 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-27698084

RESUMEN

Aag from Bacillus subtilis has been implicated in in vitro removal of hypoxanthine and alkylated bases from DNA. The regulation of expression of aag in B. subtilis and the resistance to genotoxic agents and mutagenic properties of an Aag-deficient strain were studied here. A strain with a transcriptional aag-lacZ fusion expressed low levels of ß-galactosidase during growth and early sporulation but exhibited increased transcription during late stages of this developmental process. Notably, aag-lacZ expression was higher inside the forespore than in the mother cell compartment, and this expression was abolished in a sigG-deficient background, suggesting a forespore-specific mechanism of aag transcription. Two additional findings supported this suggestion: (i) expression of an aag-yfp fusion was observed in the forespore, and (ii) in vivo mapping of the aag transcription start site revealed the existence of upstream regulatory sequences possessing homology to σG-dependent promoters. In comparison with the wild-type strain, disruption of aag significantly reduced survival of sporulating B. subtilis cells following nitrous acid or methyl methanesulfonate treatments, and the Rifr mutation frequency was significantly increased in an aag strain. These results suggest that Aag protects the genome of developing B. subtilis sporangia from the cytotoxic and genotoxic effects of base deamination and alkylation. IMPORTANCE: In this study, evidence is presented revealing that aag, encoding a DNA glycosylase implicated in processing of hypoxanthine and alkylated DNA bases, exhibits a forespore-specific pattern of gene expression during B. subtilis sporulation. Consistent with this spatiotemporal mode of expression, Aag was found to protect the sporulating cells of this microorganism from the noxious and mutagenic effects of base deamination and alkylation.


Asunto(s)
Bacillus subtilis/efectos de los fármacos , Bacillus subtilis/enzimología , Proteínas Bacterianas/metabolismo , ADN Glicosilasas/metabolismo , ADN Bacteriano/metabolismo , Hipoxantina/toxicidad , Mutágenos/toxicidad , Esporas Bacterianas/crecimiento & desarrollo , Alquilación , Bacillus subtilis/genética , Bacillus subtilis/crecimiento & desarrollo , Proteínas Bacterianas/genética , ADN Glicosilasas/genética , ADN Bacteriano/genética , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Regiones Promotoras Genéticas , Factor sigma/genética , Factor sigma/metabolismo , Esporas Bacterianas/efectos de los fármacos , Esporas Bacterianas/enzimología , Esporas Bacterianas/genética
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