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1.
J Acoust Soc Am ; 156(3): 1509-1523, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39230398

RESUMO

For prompt detection of large (>1 kt) above-ground explosions, infrasound microphone networks and arrays are deployed at surveyed locations across the world. Denser regional and local networks are deployed for smaller explosions, however, they are limited in number and are often deployed temporarily for experiments. With the expanded interest in smaller yield explosions targeted at vulnerable areas such as population centers and key infrastructures, the need for more dense microphone networks has increased. An "attritable" (affordable, reusable, and replaceable) and flexible alternative can be provided by smartphone networks. Explosion signals from a fuel air explosive (thermobaric bomb) and a high explosive with trinitrotoluene equivalent yields of 6.35 and 3.63 kg, respectively, were captured on both an infrasound microphone and a network of smartphones. The resulting waveforms were compared in time, frequency, and time-frequency domains. The acoustic waveforms collected on smartphones produced a filtered explosion pulse due to the smartphone's diminishing frequency response at infrasound frequencies (<20 Hz) and was found difficult to be used with explosion characterization methods utilizing waveform features (peak overpressure, impulse, etc.). However, the similarities in time frequency representations and additional sensor inputs are promising for other explosion signal identification and analysis. As an example, a method utilizing the relative acoustic amplitudes for source localization using the smartphone sensor network is presented.

2.
Phytopathology ; 113(6): 960-974, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36576402

RESUMO

The plant-pathogenic bacterium Xylella fastidiosa is a major threat to agriculture and the environment worldwide. Recent devastating outbreaks in Europe highlight the potential of this pathogen to cause emergent diseases. X. fastidiosa subsp. multiplex ESVL and IVIA5901 strains that belong to sequence type 6 were isolated from almond orchards within the outbreak area in Alicante province (Spain). Both strains share more than 99% of the chromosomal sequences (average nucleotide identity), but the ESVL strain harbors two plasmids (pXF64-Hb_ESVL and pUCLA-ESVL). Here, virulence phenotypes and genome content were compared between both strains, using three strains from the United States as a reference for the phenotypic analyses. Experiments in microfluidic chambers, used as a simulation of xylem vessels, showed that twitching motility was absent in the IVIA5901 strain, whereas the ESVL strain had reduced twitching motility. In general, both Spanish strains had less biofilm formation, less cell aggregation, and lower virulence in tobacco compared with U.S. reference strains. Genome analysis of the two plasmids from ESVL revealed 51 unique coding sequences that were absent in the chromosome of IVIA5901. Comparison of the chromosomes of both strains showed some unique coding sequences and single-nucleotide polymorphisms in each strain, with potential deleterious mutations. Genomic differences found in genes previously associated with adhesion and motility might explain the differences in the phenotypic traits studied. Although additional studies are necessary to infer the potential role of X. fastidiosa plasmids, our results indicate that the presence of plasmids should be considered in the study of the mechanisms of pathogenicity and adaptation in X. fastidiosa to new environments. [Formula: see text] Copyright © 2023 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.


Assuntos
Prunus dulcis , Xylella , Espanha , Virulência/genética , Doenças das Plantas/microbiologia , Plasmídeos/genética
3.
Psychiatr Q ; 91(2): 495-520, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32008210

RESUMO

Psychological approaches to the study of armed conflict have focused on analyzing post-traumatic stress outcomes, and on evaluating the intensity of exposure to violent confrontation. Nevertheless, psychometrically valid tools required for measuring these traumatic experiences are scarce To validate the Extreme Experiences scale (EX2) for armed conflict contexts for its use in Colombia, and to provide a framework for validation in conflict contexts around the world This Cross-sectional aims to validate the scale with 187 participants, study of validate with 187 participants, comprising population with high exposure to conflict (former combatants and a set of armed conflict victims) and low conflict-exposed individuals (control group). Structures of two domains and 18 items were confirmed: Direct Extreme Experiences (dEX2) and Indirect Extreme Experiences (iEX2); these dimensions were also validated by expert judgment, producing 14-item version. Good levels of internal consistency were found, with a KR-20 of 0.80 for the 18-item version, and 0.77 for the 14-item. The scale differentiates between population with 'high exposure to conflict' from population with 'low exposure' (dnp > 0.5 and area under the ROC >0.90). The scale scores have significant correlation with some mental health constructs. The EX2 scale has good internal consistency, as well as structural validity with regard to exposed groups. This scale can be potentially validated for its use in countries with armed confrontation history. In future versions, the scale may include additional items in order to improve content validity.


Assuntos
Conflitos Armados/psicologia , Inquéritos e Questionários/normas , Adulto , Estudos de Casos e Controles , Colômbia , Estudos Transversais , Feminino , Humanos , Masculino , Psicometria
4.
Br J Dermatol ; 180(3): 527-533, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30414269

RESUMO

BACKGROUND: Infantile haemangiomas (IH) are soft swellings of the skin that occur in 3-10% of infants. When haemangiomas occur in high-risk areas or when complications develop, active intervention is necessary. OBJECTIVE: To update a Cochrane Review assessing the interventions for the management of IH in children. METHODS: We searched for randomized controlled trials in CENTRAL, MEDLINE, Embase, LILACS, AMED, PsycINFO, CINAHL and six trials registers up to February 2017. We included 28 trials (1728 participants) assessing 12 interventions. RESULTS: We downgraded evidence from high to moderate/low for issues related to risk of bias and imprecision. Oral propranolol (3 mg kg-1 daily) probably improves clinician-assessed clearance vs placebo [risk ratio (RR) 16·61, 95% confidence interval (CI) 4·22-65·34; moderate quality of evidence (QoE)]; we found no evidence of a difference in terms of serious adverse events (RR 1·05, 95% CI 0·33-3·39; low QoE). We found the chance of reduction of redness may be improved with topical timolol maleate (0·5% gel applied twice daily) when compared with placebo (RR 8·11, 95% CI 1·09-60·09; low QoE). We found no instances of bradycardia or hypotension for this comparison. CONCLUSIONS: Our key results indicate that oral propranolol and topical timolol maleate are more beneficial than placebo in terms of clearance or other measures of resolution, or both, without an increase in harm.


Assuntos
Antagonistas Adrenérgicos beta/administração & dosagem , Hemangioma/tratamento farmacológico , Propranolol/administração & dosagem , Neoplasias Cutâneas/tratamento farmacológico , Timolol/administração & dosagem , Administração Cutânea , Administração Oral , Antagonistas Adrenérgicos beta/efeitos adversos , Bradicardia/induzido quimicamente , Bradicardia/epidemiologia , Abordagem GRADE , Humanos , Hipotensão/induzido quimicamente , Hipotensão/epidemiologia , Placebos/administração & dosagem , Placebos/efeitos adversos , Propranolol/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Timolol/efeitos adversos
5.
J Anim Physiol Anim Nutr (Berl) ; 99(2): 345-55, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24605885

RESUMO

The effects of three treatments of fibrolytic enzymes (cellulase from Trichoderma longibrachiatum (CEL), xylanase from rumen micro-organisms (XYL) and a 1:1 mixture of CEL and XYL (MIX) on the in vitro fermentation of two samples of Pennisetum clandestinum (P1 and P2), two samples of Dichanthium aristatum (D1 and D2) and one sample of each Acacia decurrens and Acacia mangium (A1 and A2) were investigated. The first experiment compared the effects of two methods of applying the enzymes to forages, either at the time of incubation or 24 h before, on the in vitro gas production. In general, the 24 h pre-treatment resulted in higher values of gas production rate, and this application method was chosen for a second study investigating the effects of enzymes on chemical composition and in vitro fermentation of forages. The pre-treatment with CEL for 24 h reduced (p < 0.05) the content of neutral detergent fibre (NDF) of P1, P2, D1 and D2, and that of MIX reduced the NDF content of P1 and D1, but XYL had no effect on any forage. The CEL treatment increased (p < 0.05) total volatile fatty acid (VFA) production for all forages (ranging from 8.6% to 22.7%), but in general, no effects of MIX and XYL were observed. For both P. clandestinum samples, CEL treatment reduced (p < 0.05) the molar proportion of acetate and increased (p < 0.05) that of butyrate, but only subtle changes in VFA profile were observed for the rest of forages. Under the conditions of the present experiment, the treatment of tropical forages with CEL stimulated their in vitro ruminal fermentation, but XYL did not produce any positive effect. These results showed clearly that effectiveness of enzymes varied with the incubated forage and further study is warranted to investigate specific, optimal enzyme-substrate combinations.


Assuntos
Ração Animal/análise , Celulase/metabolismo , Manipulação de Alimentos/métodos , Poaceae/química , Rúmen/fisiologia , Animais , Fermentação , Modelos Biológicos
6.
Rev Neurol ; 78(5): 127-133, 2024 Mar 01.
Artigo em Espanhol, Inglês | MEDLINE | ID: mdl-38416504

RESUMO

INTRODUCTION: Information about seasonal distribution of Neuromyelitis optica spectrum disorders (NMOSD) attacks, particularly in tropical countries, has rarely been described and the reported data are diverse. OBJECTIVE: To evaluate influence of seasonal variation in NMOSD relapses in an equatorial country. PATIENTS AND METHODS: Exploratory observational, retrospective ecological study in a cohort of patients with NMOSD followed from January 2008 to December 2019. Data of demographic, clinical information, characteristics of relapses and seasonal temporal variation were recorded. Also, the annual, monthly and intra-annual seasonal variation of relapses was quantified. A negative binomial regression was used to estimate the associations between the number of relapses and climatic and temporal variables. RESULTS: One hundred thirteen patients were included, most of them were female (89.38%), with a mean age at NMOSD diagnosis was 44.97 (±13.98) and the median of relapses per patient were 2 relapses (IQR 1-3). The patients presented 237 relapses, most of these in AQP4 seropositive patients (87.76%) and longitudinal extensive myelitis was the most frequent type of relapse (53.59%). According to the temporal variation, relapses were more common in the second rainy season (28.69%) during November and December. However, there weren't significant differences in the number of relapses between seasons and climatic variables in the multivariable model. CONCLUSION: The number of NMOSD relapses in this equatorial country cohort did not exhibit any significant associations with climatic variations, including changes in rainy or dry seasons.


TITLE: Recaídas del trastorno de espectro de la neuromielitis óptica e influencia estacional en una cohorte de un país ecuatorial.Introducción. La evidencia sobre la distribución estacional de las recaídas del trastorno del espectro de la neuromielitis óptica (NMOSD), especialmente en países tropicales, es limitada y diversa. Objetivo. Evaluar la influencia de las variaciones estacionales en las recaídas del NMOSD en un país localizado sobre la línea ecuatorial. Pacientes y métodos. Se llevó a cabo un estudio ecológico, con información retrospectiva de una cohorte de pacientes con NMOSD atendida entre enero de 2003 y diciembre de 2020 en Medellín, Colombia. Se recolectaron datos demográficos y clínicos de los pacientes, así como información sobre variables estacionales y climáticas. Se calculó la frecuencia de recaídas por estación, mes y año, y se realizó una regresión binomial negativa para evaluar la asociación entre el número de recaídas, y las variables estacionales y climáticas. Resultados. Se incluyó a 113 pacientes, de los cuales el 89,38% eran mujeres, con una edad media en el momento del diagnóstico de NMOSD de 44,97 (±13,98) años y una mediana de tres recaídas (rango intercuartílico: 1-2). Se registraron 237 recaídas, la mayoría en pacientes seropositivos para anticuerpos antiacuaporina 4 (87,76%) y con mielitis longitudinal extensa como la presentación clínica más común (53,59%). Las recaídas se presentaron con mayor frecuencia durante la segunda temporada lluviosa (28,69%; n = 68), y en los meses de noviembre y diciembre. Sin embargo, en la regresión binomial negativa no se observó una asociación significativa entre el número de recaídas y las variables climáticas y estacionales, los meses y los años. Conclusión. Las variables climáticas y los patrones estacionales no muestran una asociación significativa con cambios en el número de recaídas del NMOSD en pacientes residentes en un país localizado sobre la línea ecuatorial.


Assuntos
Neuromielite Óptica , Humanos , Feminino , Masculino , Neuromielite Óptica/epidemiologia , Estações do Ano , Estudos Retrospectivos , Doença Crônica , Projetos de Pesquisa
7.
Rev Neurol ; 74(11): 347-352, 2022 06 01.
Artigo em Espanhol | MEDLINE | ID: mdl-35635360

RESUMO

INTRODUCTION: Disability in neuromyelitis optica spectrum disorder (NMOSD) is common and can be severe. AIM: To determine factors associated with increased disability in NMOSD. PATIENTS AND METHODS: Observational, analytical, ambispective study in a cohort of patients with NMOSD between January 2015 and July 2021, using a secondary source to review variables and the expanded disability status scale (EDSS) after onset and a primary source, with a telephone survey for the final EDSS and missing data. Major disability was defined as occurring when the EDSS score was = 6. The analysis was performed by means of logistic regression with SPSS 25®. RESULTS: A total of 125 patients were analysed. The average age at onset was 41 (standard deviation: 14) years, with a female-to-male ratio of 8:1. Of the total sample, 87% (109) were positive for anti-aquaporin antibodies. Optic neuritis (44.8%) and transverse myelitis (39.2%) were the most frequent clinical manifestations at onset. Altogether 71.2% of patients received acute treatment at their first relapse. Mean chronic treatment initiation was 12 months (interquartile range: 3-60) and 44% had difficulties with immunosuppression compliance. Of the total number of patients, 80.8% had relapses and 44% had a final EDSS score = 6. The median baseline-to-final EDSS score was 1 (interquartile range: 0-3), often towards disability accumulation. An association was found between a relapsing course (odds ratio = 3.73; p = 0.011) and a high baseline EDSS (odds ratio = 1.54; p = 0.0001) with increased disability. In the multivariate analysis, with a higher baseline EDSS and a relapsing course disability was 1.6 and 5.3 times more likely to occur, respectively. CONCLUSIONS: Disease relapses and high EDSS after the first episode are predictors of disability in NMOSD.


TITLE: Predictores de discapacidad en una cohorte con espectro de neuromielitis óptica.Introducción. La discapacidad en el espectro de neuromielitis óptica (NMOSD) es frecuente y puede ser grave. Objetivo. Determinar factores asociados a mayor discapacidad en el NMOSD. Pacientes y métodos. Estudio observacional, analítico, ambispectivo, en una cohorte de pacientes con NMOSD entre enero de 2015 y julio de 2021, utilizando una fuente secundaria para la revisión de variables y la escala extendida de discapacidad (EDSS) después del inicio y una fuente primaria, con una encuesta telefónica para la EDSS final y los datos faltantes. Se definió la discapacidad mayor cuando la puntuación de la EDSS era = 6. El análisis se realizó por medio de regresión logística con SPSS 25®. Resultados. Se analizó a 125 pacientes. La edad promedio de inicio fue 41 (desviación estándar: 14) años, con una relación mujer:hombre de 8:1. El 87% (109) era positivo para anticuerpos antiacuaporinas. La neuritis óptica (44,8%) y la mielitis transversa (39,2%) fueron las manifestaciones clínicas más frecuentes en el inicio. El 71,2% de los pacientes recibió tratamiento agudo en la primera recaída. La mediana de inicio del tratamiento crónico fue de 12 meses (rango intercuartílico: 3-60) y el 44% tuvo dificultades en el cumplimiento de la inmunosupresión. El 80,8% presentó recaídas y el 44% tenía una puntuación en la EDSS final = 6. La mediana de EDSS basal-final fue de 1 (rango intercuartílico, 0-3), con frecuencia hacia la acumulación de discapacidad. Se encontró asociación entre el curso con recaídas (odds ratio = 3,73; p = 0,011) y la EDSS basal alta (odds ratio = 1,54; p = 0,001) con una mayor discapacidad. En el análisis multivariado, una mayor EDSS basal y un curso con recaídas presentaron una probabilidad de discapacidad 1,6 y 5,3 veces mayor, respectivamente. Conclusiones. Las recaídas de la enfermedad y la EDSS alta después del primer episodio son predictores de discapacidad en el NMOSD.


Assuntos
Pessoas com Deficiência , Neuromielite Óptica , Estudos de Coortes , Feminino , Humanos , Masculino , Neuromielite Óptica/epidemiologia , Recidiva , Fatores de Risco
8.
Heliyon ; 7(4): e06811, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33948520

RESUMO

OBJECTIVE: Primary outcome was to evaluate complete improvement at six months after acute treatment in NMOSD relapses. METHODS: Retrospective observational cohort study of patients with diagnosis of NMOSD admitted for acute attacks. We performed an explanatory analysis using the univariate, bivariate and multivariate logistic regression approach. We compared survival curves using the Kaplan Meier analysis and estimated the median time for the main outcome. RESULTS: In the univariate analysis, basal EDSS score, AQP4-IgG positivity, PLEX as a first-line treatment (IVMP + PLEX), less systemic complications related to acute treatment and total attack history were independently associated with complete improvement at six months. After adjusting for confounding variables and using multivariate analysis by Cox Regression, positive AQ4-IgG (HR 0.04, 95% CI: 0.02-0.66) and IVMP + PLEX (HR 5.1, 95% CI: 3.9-66.4), were kept as independent factors associated to time to complete improvement. Time from admission to PLEX initiation and complete improvement at six months had a median of seven days (95% CI: 5.2-8.8). In secondary effects, there were no statistical differences between the groups. CONCLUSIONS: PLEX + IVMP is the treatment of choice for NMOSD relapses and should be initiated as early as possible.

10.
An Med Interna ; 24(9): 431-4, 2007 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-18198951

RESUMO

The case of 20-years female patient with the diagnosis of sarcoidosis associated to fibrolamellar carcinoma of the liver is presented. Clinical features, diagnosis and treatment of these entities are exposed. The criteria of several researchers about the relation between sarcoidosis and neoplasic diseases are stood out. Sarcoidosis associated to fibrolamellar hepatocarcinoma is very uncommon.


Assuntos
Carcinoma Hepatocelular/patologia , Hepatopatias/complicações , Neoplasias Hepáticas/patologia , Sarcoidose/complicações , Adulto , Carcinoma Hepatocelular/complicações , Feminino , Humanos , Neoplasias Hepáticas/complicações
11.
Materials (Basel) ; 10(9)2017 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-28880233

RESUMO

Magnetoelectric force microscopy (MeFM) is characterized as methodical tool for the investigation of antiferromagnetic domain states, in particular of the 180 ∘ variety. As reference compound for this investigation we use Cr 2 O 3 . Access to the antiferromagnetic order is provided by the linear magnetoelectric effect. We resolve the opposite antiferromagnetic 180 ∘ domain states of Cr 2 O 3 and estimate the sensitivity of the MeFM approach, its inherent advantages in comparison to alternative techniques and its general feasibility for probing antiferromagnetic order.

12.
Arch Soc Esp Oftalmol ; 91(2): 94-6, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26710660

RESUMO

OBJECTIVE: Neonatal herpes simple virus (HSV) keratitis, relatively uncommon are associated with significant morbidity. CASE REPORT: The case is presented of a newborn girl who developed herpes simplex virus (HSV) keratoconjunctivitis, despite a vaginal delivery, and the absence of medical history or active clinical maternal HSV infection. Diagnosis relies on a high level of clinical suspicion and the use of diagnostic tests. DISCUSSION: Neonatal herpes simplex virus (HSV) keratitis, although relatively uncommon, is associated with significant morbidity.


Assuntos
Herpes Simples/diagnóstico , Ceratite/diagnóstico , Complicações Infecciosas na Gravidez/diagnóstico , Antivirais/uso terapêutico , Feminino , Humanos , Recém-Nascido , Ceratoconjuntivite/tratamento farmacológico , Gravidez
13.
J Expo Sci Environ Epidemiol ; 26(3): 257-62, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25993025

RESUMO

Sufficient epidemiologic evidence has established an etiologic link between bladder cancer risk and occupational exposure as a painter to organic solvents. Currently, it remains to be established whether gene-specific promoter methylation contributes to bladder cancer development, including by enhancing chromosome breakage or loss. We investigated the effect of chronic exposure to organic solvents and paints on DNA methylation profiles in the promoter regions of four genes (GSTP1, p16(INK4a), APC and CDH1) and micronucleus (MN) frequency in exfoliated urothelial cells from voided urine from Colombian male non-smoking car painters and age-matched unexposed individuals. The exposed group had a higher percentage of individuals with >2 MNs/2000 cells compared with the unexposed group (P=0.04). Gene-specific analysis showed a significantly higher percentage of individuals with methylated GSTP1, p16(INK4a) and APC in the exposed group. Poisson regression analysis indicated that exposed individuals with methylated GSTP1 and p16(INK4a) promoters were more than twofold more likely to have an increase in MN frequency as compared with the reference. Finally, among exposed individuals with GSTP1 and p16(INK4a) methylated promoters, those with a greater age had a higher RR of increased MN frequency compared with younger exposed individuals with methylated promoters. These results support the conclusion that gene-specific promoter methylation may increase MN frequency in a dependent or independent interaction with occupational exposure to organic solvents.


Assuntos
Metilação de DNA , Testes para Micronúcleos , Exposição Ocupacional , Pintura/toxicidade , Regiões Promotoras Genéticas , Solventes/toxicidade , Urotélio/efeitos dos fármacos , Humanos , Masculino , Urotélio/citologia
14.
Carbohydr Polym ; 117: 910-916, 2015 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-25498716

RESUMO

5-Caffeoylquinic acid (chlorogenic acid), is classified in acid-phenols family and as polyphenolic compounds it possesses antioxidant activity. The oxydative modification of chlorogenic acid in foods may lead to alteration of their qualities; to counteract these degradation effects, molecular encapsulation was used to protect chlorogenic acid. Amylose can interact strongly with a number of small molecules, including lipids. In order to enable chlorogenic acid complexation by amylose, a C16 aliphatic chain was previously grafted onto the cycle of quinic acid. This work showed that for the two lipophilic derivatives of chlorogenic acid: hexadecyl chlorogenate obtained by alkylation and 3-O-palmitoyl chlorogenic acid obtained by acylation; only the 3-O-palmitoyl chlorogenic acid complexed amylose. The chlorogenic acid derivatives were studied by X-ray diffraction, differential scanning calorimetry and NMR to elucidate the interaction. By comparing the results with previous work on the complexation of amylose by 4-O-palmitoyl chlorogenic acid, the importance of the aliphatic chain position on the cycle of the quinic acid is clearly highlighted. A study in molecular modeling helped to understand the difference in behavior relative to amylose of these three derivatives of chlorogenic acid.


Assuntos
Amilose/química , Ácido Clorogênico/química , Modelos Moleculares , Conformação Molecular , Temperatura
15.
Am J Trop Med Hyg ; 61(2): 245-8, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10463674

RESUMO

Sulfadoxine/pyrimethamine (SP) is considered an alternative treatment for acute uncomplicated malaria caused by Plasmodium falciparum resistant to chloroquine. However, the appearance of resistance to this drug has been reported since its initial use in Colombia. Molecular analysis of the dihydrofolate reductase gene indicates a correlation between in vitro resistance to SP and the Asn-108 point mutation. Little is known about the association of this point mutation and in vivo resistance to SP. We used a mutation-specific polymerase chain reaction strategy to analyze the presence of the Asn-108 point mutation in 48 clinical samples with adequate clinical response (ACR), 2 early treatment failures (ETF), and 1 late treatment failure (LTF). The Asn-108 mutation was detected in 36 of the ACR samples and in all of the ETF and LTF samples. Eleven ACR samples amplified with the wild-type-specific primer and one amplified with the primer for the Thr-108 mutation described for resistance to cycloguanil. These results suggest that the Asn-108 marker may not be useful in predicting SP treatment failure.


Assuntos
Antimaláricos/uso terapêutico , Malária Falciparum/tratamento farmacológico , Plasmodium falciparum/genética , Mutação Puntual , Pirimetamina/uso terapêutico , Sulfadoxina/uso terapêutico , Tetra-Hidrofolato Desidrogenase/genética , Animais , Combinação de Medicamentos , Resistência a Medicamentos/genética , Eletroforese em Gel de Ágar , Amplificação de Genes , Marcadores Genéticos , Humanos , Malária Falciparum/parasitologia , Plasmodium falciparum/efeitos dos fármacos , Reação em Cadeia da Polimerase
16.
Am J Trop Med Hyg ; 59(1): 124-8, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9684639

RESUMO

Several point mutations in the dihydrofolate reductase (DHFR) gene of Plasmodium falciparum have been correlated with in vitro anti-folate drug resistance of laboratory and field isolates. Furthermore, two different point mutations that generate amino acid substitutions at the same position of the enzyme have been observed in all the isolates studied to date. These point mutations change a serine (Ser-108) in the wild type to an asparagine (Asn-108 mutation) or to a threonine (Thr-108 mutation). Using the polymerase chain reaction (PCR), it is possible to identify isolates that present these mutations. We used a mutation-specific PCR to screen 71 samples from several geographic locations of Colombia for the Asn-108 mutation (pyrimethamine resistance). In this initial screening 53 of 71 yielded amplification product with the DHFR mutation-specific primers. We further analyzed the 18 samples that did not amplify using a mutation-specific nested PCR. Of those 18 samples, seven amplified with primers specific for the Thr-108 mutation (proguanil resistance), one with the wild type (Ser-108), and 10 did not amplify. Of these 10 samples, three were identified as P. falciparum using a species-specific diagnostic nested PCR base on sequences from the small ribosomal RNA subunit gene. Overall, 51.6% of the samples amplified for the Asn-108 mutation, 10.9% for the Thr-108 mutation, 35.9% with the wild type specific primer, and 4.8% did not amplify with any of the DHFR primers. We observed variability in the frequency of the mutation between the different geographic location. The frequency of the Asn-108 and Thr-108 mutations in the state of Narifio was 25% each, while in Valle del Cauca the frequencies were 59% and 11%, respectively. These results contrast with observations in Brazil in which the Asn-108 mutation was found in 90% of the blood samples screened.


Assuntos
DNA de Protozoário/química , Malária Falciparum/parasitologia , Plasmodium falciparum/genética , Mutação Puntual , Tetra-Hidrofolato Desidrogenase/genética , Adolescente , Adulto , Animais , Asparagina/química , Criança , Pré-Escolar , Colômbia , DNA de Protozoário/sangue , Feminino , Frequência do Gene , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Parasitemia/parasitologia , Plasmodium falciparum/enzimologia , Reação em Cadeia da Polimerase , Serina/química , Tetra-Hidrofolato Desidrogenase/química , Treonina/química
17.
Am J Trop Med Hyg ; 61(6): 968-72, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10674680

RESUMO

Although chloroquine (CQ) resistance was first reported in Colombia in 1961 and sulfadoxine-pyrimethamine (SP) resistance in 1981, the frequency of treatment failures to these drugs in Colombia is unclear. A modified World Health Organization 14-day in vivo drug efficacy test for uncomplicated Plasmodium falciparum malaria in areas with intense malaria transmission was adapted to reflect the clinical and epidemiologic features of a low-intensity malaria transmission area in the Pacific Coast Region of Colombia. Patients > or =1 year of age with a parasite density > or =1,000 asexual parasites per microliter were enrolled in this study. Forty-four percent (24 of 54) of the CQ-treated patients were therapeutic failures, including 7 early treatment failures (ETFs) and 17 late treatment failures (LTFs). Four (6%) of 67 SP-treated patients were therapeutic failures (2 ETFs and 2 LTFs). Therapeutic failure in the CQ-treated group was associated with an age <15 years old (P < 0.01), but was not associated with initial parasite density, the presence of CQ or sulfa-containing drugs in urine, or a history of malaria. The high level of therapeutic failures to CQ detected in this study underscores the need and importance of drug efficacy evaluation in the development of a rational national antimalarial drug policy. The relatively low level of therapeutic failures to SP compared with other South American countries raises further questions regarding factors that might have prevented the rapid development of in vivo resistance to this drug combination.


Assuntos
Antimaláricos/uso terapêutico , Cloroquina/uso terapêutico , Malária Falciparum/tratamento farmacológico , Plasmodium falciparum/efeitos dos fármacos , Pirimetamina/uso terapêutico , Sulfadoxina/uso terapêutico , Adolescente , Adulto , Animais , Antimaláricos/farmacologia , Criança , Pré-Escolar , Cloroquina/farmacologia , Colômbia , Transmissão de Doença Infecciosa , Combinação de Medicamentos , Resistência a Medicamentos , Feminino , Humanos , Lactente , Malária Falciparum/transmissão , Masculino , Pessoa de Meia-Idade , Plasmodium falciparum/isolamento & purificação , Pirimetamina/farmacologia , Sulfadoxina/farmacologia , Falha de Tratamento
18.
Am J Primatol ; 38(1): 85-100, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-31914712

RESUMO

Groups of individually marked cotton-top tamarins (Saguinus oedipus), located in La Reserva Forestal Protectora Serranía de Coraza-Montes de María in Colosó Colombia, were studied over a period of 5 years. Data on group composition, stability, birthing seasons, and dispersal patterns are used to examine the reproductive strategies and tactics used by males and females. Both monogamous groups and groups containing two pregnant females have been observed. All groups contained at least one adult female and male, with several groups containing several adult males and females. Both males and females dispersed to neighboring groups, and there were no sex differences in rates of emigration. Males were more likely to immigrate into a new group following the death/emigration of a resident male. Females appeared to tolerate immigrating females but would actively defend their breeding position during fertile periods. © 1996 Wiley-Liss, Inc.

19.
Am J Primatol ; 31(3): 189-196, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-31936998

RESUMO

We present reliable field techniques for capturing, anesthetizing, and Iidentifying individual cotton-top tamarins (Saguinus oedipus oedipus). A new technique is presented for radio-tracking small bodied primates. A backpack-style harness was designed to carry a transmitter. This system appears effective in minimizing potential injury and does not appear to interfere with the normal behavior of the animal. © 1993 Wiley-Liss, Inc.

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