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1.
Trop Med Health ; 52(1): 36, 2024 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-38734710

RESUMEN

BACKGROUND: To fight the current coronavirus disease (COVID-19) pandemic, many countries have implemented various mitigation measures to contain the spread of the disease. By engaging with health service providers, the community's participation in adherence to preventive measures is certainly required in the implementation of COVID-19 mitigation strategies. Therefore, this study aimed to assess the level of adherence to COVID-19 preventive measures and its associated factors among the residents, Yangon Region, Myanmar. METHODS: A community-based cross-sectional study was carried out among 636 residents in Yangon Region, Myanmar, from October to December 2021. A multistage non-probability sampling method, purposively selected for three townships in Yangon Region and convenience sampling for 212 participants from each township, was applied and the data were collected by face-to-face interviews using structured and pretested questionnaires. Data were entered, coded, and analyzed using IBM SPSS version 25.0. Simple and multiple logistic regression analysis were performed to identify the significant variables of adherence to COVID-19 preventive measures. RESULTS: As a level of adherence to COVID-19 preventive measures, the proportion of residents who had good adherence was 39.3% (95% CI 35.5-43.2%), moderate adherence was 37.6% (95% CI 33.8-41.5%), and poor adherence was 23.1% (95% CI 19.9-26.6%). The age group of 31-40 years (AOR: 3.13, 95% CI 1.62-6.05), 30 years and younger (AOR: 3.22, 95% CI 1.75-5.92), Burmese ethnicity (AOR: 2.52, 95% CI 1.44-4.39), own business (AOR: 3.19, 95% CI 1.15-8.87), high school education level and below (AOR: 1.64, 95% CI 1.02-2.69), less than 280.90 USD of monthly family income (AOR: 1.51, 95% CI 1.01-2.29), low knowledge about COVID-19 (AOR: 1.90, 95% CI 1.26-2.88) were significantly associated with poor adherence to COVID-19 preventive measures. CONCLUSIONS: In this study, nearly one-fourth of the residents were experiencing poor adherence to COVID-19 preventive measures. Therefore, building up the risk communication through the community using widely used mainstream media, the continuation of disease surveillance and announcement of updated information or advice for the public to increase awareness towards COVID-19, and enforcement to follow the recommended directions and regulations of health institutions are vital to consider for improving the adherence to preventive measures against COVID-19 among the residents.

2.
Gynecol Minim Invasive Ther ; 13(1): 30-36, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38487612

RESUMEN

Objectives: This study aimed to evaluate the effectiveness of prophylactic laparoscopic surgery for avoiding adnexal torsion in pregnant women with benign adnexal masses. Materials and Methods: This report contains two analyses, each for a different group of patients. Analysis 1: Surgical and pregnancy outcomes were examined among the 126 cases who underwent laparoscopic assisted cystectomy for adnexal masses during pregnancy in our hospital between January 2001 and December 2020. Analysis 2: The incidence of adnexal torsion during pregnancy was evaluated among the cases with adnexal masses ≥5 cm who opted for conservative follow-up in our hospital between January 2011 and December 2020. Results: In analysis 1, the most common pathological diagnosis was a mature cystic teratoma (76.2%). The mean gestational age at surgery was 13.1 ± 1.3 weeks. No cases were converted to laparotomy and oophorectomy. Regarding delivery outcomes, 97.4% of cases went on to have full-term deliveries. In Analysis 2, the incidence of adnexal mass ≥5 cm that did not resolve spontaneously during pregnancy was 89 cases (0.8%). The frequency of malignancy was 3 cases (0.03%). In 28 cases who opted for conservative treatment, 5 (17.9%) underwent emergency surgery for adnexal torsion. Conclusion: Prophylactic surgery for benign adnexal masses during pregnancy can be performed laparoscopically and preserved ovarian functions. In pregnant women with adnexal masses that do not resolve spontaneously, planning laparoscopic surgery is considered beneficial for complications, such as adnexal torsion.

3.
Int J Biol Macromol ; 253(Pt 8): 127668, 2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-37884238

RESUMEN

Rapid evolution of pest resistance to Bt insecticidal proteins presents a serious threat to the sustainable use of Bt crops. The cotton bollworm has been extensively exposed to Bt cotton worldwide and has evolved resistance in laboratory and field. Previous studies have highlighted the significant roles played by the ABC transporter proteins in Bt resistance. In this study, the ORF of HaABCB1 was cloned and analyzed. The expression of HaABCB1 was detected in all developmental stages and tissues, with the highest expression in third instar larvae stage and hindgut tissue. Compared with susceptible strain, a remarkable decrease of HaABCB1 expression in Cry1Ac resistant strain while no significant change in Cry2Ab resistant strain were found. The HaABCB1 expression reduced after susceptible larvae induced by Cry1Ac, but no obvious expression changes after Cry2Ab exposure. RNAi-mediated down-regulation of HaABCB1 could lead to a significant reduction in larval susceptibility to Cry1Ac, but not to Cry2Ab, in susceptible strain. Genetic linkage analysis confirmed that decreased expression of the HaABCB1 mediates resistance to Cry1Ac, but not Cry2Ab resistance. This knowledge contributes to better understanding of the complex molecular mechanisms underlying Bt resistance and provide theoretical foundation for the development of new strategies for pest resistance management.


Asunto(s)
Bacillus thuringiensis , Mariposas Nocturnas , Animales , Bacillus thuringiensis/genética , Bacillus thuringiensis/metabolismo , Endotoxinas/genética , Endotoxinas/farmacología , Endotoxinas/metabolismo , Toxinas de Bacillus thuringiensis/metabolismo , Resistencia a los Insecticidas/genética , Mariposas Nocturnas/genética , Mariposas Nocturnas/metabolismo , Larva/genética , Larva/metabolismo , Subfamilia B de Transportador de Casetes de Unión a ATP/genética , Subfamilia B de Transportador de Casetes de Unión a ATP/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/farmacología , Proteínas Bacterianas/metabolismo , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/farmacología , Proteínas Hemolisinas/metabolismo , Gossypium/metabolismo
4.
Appl Environ Microbiol ; 89(7): e0062523, 2023 07 26.
Artículo en Inglés | MEDLINE | ID: mdl-37378519

RESUMEN

Midgut receptors play a critical role in the specificity of Cry toxins for individual insect species. Cadherin proteins are essential putative receptors of Cry1A toxins in lepidopteran larvae. Cry2A family members share common binding sites in Helicoverpa armigera, and one of them, Cry2Aa, has been widely reported to interact with midgut cadherin. Here, we studied the binding interaction and functional role of H. armigera cadherin in the mechanism of Cry2Ab toxicity. A region spanning from cadherin repeat 6 (CR6) to the membrane-proximal region (MPR) of cadherin protein was produced as six overlapping peptides to identify the specific binding regions of Cry2Ab. Binding assays showed that Cry2Ab binds nonspecifically to peptides containing CR7 and CR11 regions in a denatured state but binds specifically only to CR7-containing peptides in the native state. The peptides CR6-11 and CR6-8 were transiently expressed in Sf9 cells to assess the functional role of cadherin. Cytotoxicity assays showed that Cry2Ab is not toxic to the cells expressing any of the cadherin peptides. However, ABCA2-expressing cells showed high sensitivity to Cry2Ab toxin. Neither increased nor decreased sensitivity to Cry2Ab was observed when the peptide CR6-11 was coexpressed with the ABCA2 gene in Sf9 cells. Instead, treating ABCA2-expressing cells with a mixture of Cry2Ab and CR6-8 peptides resulted in significantly reduced cell death compared with treatment with Cry2Ab alone. Moreover, silencing of the cadherin gene in H. armigera larvae showed no significant effect on Cry2Ab toxicity, in contrast to the reduced mortality in ABCA2-silenced larvae. IMPORTANCE To improve the efficiency of production of a single toxin in crops and to delay the evolution of insect resistance to the toxin, the second generation of Bt cotton, expressing Cry1Ac and Cry2Ab, was introduced. Understanding the mode action of the Cry proteins in the insect midgut and the mechanisms insects use to overcome these toxins plays a crucial role in developing measures to counter them. Extensive studies have been conducted on the receptors of Cry1A toxins, but relatively little has been done about those of Cry2Ab. By showing the nonfunctional binding of cadherin protein with Cry2Ab, we have furthered the understanding of Cry2Ab receptors.


Asunto(s)
Toxinas de Bacillus thuringiensis , Helicoverpa armigera , Proteínas de Insectos , Receptores de Superficie Celular , Helicoverpa armigera/crecimiento & desarrollo , Helicoverpa armigera/metabolismo , Helicoverpa armigera/microbiología , Animales , Bacillus thuringiensis/metabolismo , Toxinas de Bacillus thuringiensis/química , Toxinas de Bacillus thuringiensis/metabolismo , Receptores de Superficie Celular/metabolismo , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Transportadoras de Casetes de Unión a ATP/metabolismo , Larva/metabolismo , Técnicas de Silenciamiento del Gen , Células Sf9
5.
J Agric Food Chem ; 71(5): 2279-2289, 2023 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-36710440

RESUMEN

Reduced insecticide spray in crop fields due to the widespread adoption of Bacillus thuringiensis (Bt) crops has favored the population increases of mirid bugs. Cry51Aa proteins are new types of Bt proteins that belong to aerolysin-like ß pore-forming proteins with insecticidal activity against hemipteran and coleopteran pests. Here, we studied the activity of Bt Cry51Aa1 and Cry51Aa2 against Apolygus lucorum, an emerging pest in cotton, and their mechanism of action. Cry51Aa1 exhibited almost 5-fold higher toxicity than Cry51Aa2 with LC50 of 11.87 and 61.34 µg/mL, respectively. Protoxins could be activated both in vitro, by trypsin and midgut contents, and in vivo, by A. lucorum midgut. Both Cry51Aa protoxins were processed in two steps, producing pre-activated (∼30 kDa) and final activated (∼25-28 kDa) proteins. Cry51Aa proteins bound to a 25 kDa midgut protein, and Cry51Aa2 showed 2 times higher binding affinity than Cry51Aa1. Incubating Cry51Aa proteins with midgut homogenate resulted in toxin oligomers of 150-200 kDa. Our findings provide a theoretical basis for using Cry51Aa proteins to control A. lucorum and a better understanding of their mode of action.


Asunto(s)
Bacillus thuringiensis , Proteínas Bacterianas , Heterópteros , Insecticidas , Animales , Bacillus thuringiensis/química , Bacillus thuringiensis/metabolismo , Proteínas Bacterianas/química , Proteínas Bacterianas/farmacología , Endotoxinas , Proteínas Hemolisinas , Heterópteros/efectos de los fármacos , Insecticidas/química , Insecticidas/farmacología
6.
Pestic Biochem Physiol ; 188: 105269, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36464374

RESUMEN

Insect resistance to Bacillus thuringiensis (Bt) is a critical limiting factor for applying the Bt crops. Some studies indicated that decreased protoxin activation because of lower enzymatic activities of trypsin and chymotrypsin and increased expression of serpin might involve in Bt resistance. Our previous study identified an endogenous serpin could inhibit the midgut proteases to activate Cry1Ac and reduce the insecticide activity to Helicoverpa armigera. We hypothesis that up-regulated serpin involve in resistance via inhibiting enzymatic activities of trypsin and chymotrypsin to decrease protoxin activation. Herein, we found the serpin-e gene relative expression in midgut was significantly higher in the LF30 resistant strain than that in the susceptible strain during all developmental stages. Importantly, RNAi-mediated silencing of serpin-e gene expression caused 4.46-fold mortality changes in LF30 strain, but the trypsin and chymotrypsin proteases activities were only changed 0.79-fold and 2.22-fold. In addition, although proteases activities were significantly lower in LF30 strain than that in the susceptible strain, the resistance ratios of LF30 to Cry1Ac protoxin and to activated Cry1Ac toxin were no difference. The results indicated serpins caused insect resistance to Cry1Ac protoxins partly through inhibiting the trypsin and chymotrypsin proteases activities, but it also existed other mechanisms in LF30.


Asunto(s)
Bacillus thuringiensis , Mariposas Nocturnas , Serpinas , Animales , Serpinas/genética , Quimotripsina/genética , Tripsina , Péptido Hidrolasas , Mariposas Nocturnas/genética
7.
Ecol Process ; 11(1): 65, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36397837

RESUMEN

Background: Transitional economies in Southeast Asia-a distinct group of developing countries-have experienced rapid urbanization in the past several decades due to the economic transition that fundamentally changed the function of their economies, societies and the environment. Myanmar, one of the least developed transitional economies in Southeast Asia, increased urbanization substantially from 25% in 1990 to 31% in 2019. However, major knowledge gaps exist in understanding the changes in urban land use and land cover and environment and their drivers in its cities. Methods: We studied Yangon, the largest city in Myanmar, for the urbanization, environmental changes, and the underlying driving forces in a radically transitioned economy in the developing world. Based on satellite imagery and historic land use maps, we quantified the expansion of urban built-up land and constructed the land conversion matrix from 1990 through 2020. We also used three air pollutants to illustrate the changes in environmental conditions. We analyzed the coupled dynamics among urbanization, economic development, and environmental changes. Through conducting a workshop with 20 local experts, we further analyzed the influence of human systems and natural systems on Yangon's urbanization and sustainability. Results: The city of Yangon expanded urban built-up land rapidly from 1990 to 2000, slowed down from 2000 to 2010, but gained momentum again from 2010 to 2020, with most newly added urban built-up land appearing to be converted from farmland and green land in both 1990-2000 and 2010-2020. Furthermore, the air pollutant concentration of CO decreased, but that of NO2 and PM2.5 increased in recent years. A positive correlation exists between population and economic development and the concentration of PM2.5 is highly associated with population, the economy, and the number of vehicles. Finally, the expert panel also identified other potential drivers for urbanization, including the extreme climate event of Cyclone Nargis, capital relocation, and globalization. Conclusions: Our research highlights the dramatic expansion of urban land and degradation of urban environment measured by air pollutants and interdependent changes between urbanization, economic development, and environmental changes.

8.
Pestic Biochem Physiol ; 175: 104837, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33993962

RESUMEN

Bt protoxins are required to convert to a smaller activated form by insect midgut proteases to exert toxicity against insect pests. Serine protease inhibitors (serpins) play a valuable part in gut protease of insect that hamper digestive proteases activity of insects. Whether the insect serpins induced by Bt protoxin affect the insecticidal activity were rare studied. Here, we identified a serpin-e gene from Helicoverpa armigera, which had potential RCL (Reactive Center Loop) region near the C-terminus like other serpin proteins. It widely expressed in different development stages and in various tissues, but highest expressed in fourth-instar larvae and in larval hemolymph. This Haserpin-e could be induced by Cry1Ac protoxin in vivo and inhibit the midgut proteases to activate Cry1Ac in vitro. Importantly, the functional study indicated it could inhibit the process from Cry1Ac protoxin to activated toxin, and led to the reduction of Cry1Ac insecticide activity to cotton bollworm. Based on our results, we proposed that Haserpin-e involved in the toxicity of Cry1Ac to cotton bollworm by blocking the serine protease to activate the protoxin.


Asunto(s)
Bacillus thuringiensis , Mariposas Nocturnas , Serpinas , Animales , Toxinas de Bacillus thuringiensis , Proteínas Bacterianas/genética , Endotoxinas/toxicidad , Proteínas Hemolisinas/toxicidad , Resistencia a los Insecticidas , Larva , Serpinas/genética
9.
Blood Adv ; 2(15): 1998-2011, 2018 08 14.
Artículo en Inglés | MEDLINE | ID: mdl-30108108

RESUMEN

Robust ß-globin expression in erythroid cells derived from induced pluripotent stem cells (iPSCs) increases the resolution with which red blood cell disorders such as sickle cell disease and ß thalassemia can be modeled in vitro. To better quantify efforts in augmenting ß-globin expression, we report the creation of a ß-globin reporter iPSC line that allows for the mapping of ß-globin expression throughout human erythropoietic development in real time at single-cell resolution. Coupling this tool with single-cell RNA sequencing (scRNAseq) identified features that distinguish ß-globin-expressing cells and allowed for the dissection of the developmental and maturational statuses of iPSC-derived erythroid lineage cells. Coexpression of embryonic, fetal, and adult globins in individual cells indicated that these cells correspond to a yolk sac erythromyeloid progenitor program of hematopoietic development, representing the onset of definitive erythropoiesis. Within this developmental program, scRNAseq analysis identified a gradient of erythroid maturation, with ß-globin-expressing cells showing increased maturation. Compared with other cells, ß-globin-expressing cells showed a reduction in transcripts coding for ribosomal proteins, increased expression of members of the ubiquitin-proteasome system recently identified to be involved in remodeling of the erythroid proteome, and upregulation of genes involved in the dynamic translational control of red blood cell maturation. These findings emphasize that definitively patterned iPSC-derived erythroblasts resemble their postnatal counterparts in terms of gene expression and essential biological processes, confirming their potential for disease modeling and regenerative medicine applications.


Asunto(s)
Eritroblastos/metabolismo , Eritropoyesis , Regulación de la Expresión Génica , Células Madre Pluripotentes Inducidas/metabolismo , Globinas beta/biosíntesis , Línea Celular Transformada , Eritroblastos/citología , Humanos , Células Madre Pluripotentes Inducidas/citología
10.
Stem Cells ; 36(7): 1004-1019, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29569827

RESUMEN

Induced pluripotent stem cells (iPSCs) stand to revolutionize the way we study human development, model disease, and eventually, treat patients. However, these cell sources produce progeny that retain embryonic and/or fetal characteristics. The failure to mature to definitive, adult-type cells is a major barrier for iPSC-based disease modeling and drug discovery. To directly address these concerns, we have developed a chemically defined, serum and feeder-free-directed differentiation platform to generate hematopoietic stem-progenitor cells (HSPCs) and resultant adult-type progeny from iPSCs. This system allows for strict control of signaling pathways over time through growth factor and/or small molecule modulation. Through direct comparison with our previously described protocol for the production of primitive wave hematopoietic cells, we demonstrate that induced HSPCs are enhanced for erythroid and myeloid colony forming potential, and strikingly, resultant erythroid-lineage cells display enhanced expression of adult ß globin indicating definitive pathway patterning. Using this system, we demonstrate the stage-specific roles of two key signaling pathways, Notch and the aryl hydrocarbon receptor (AHR), in the derivation of definitive hematopoietic cells. We illustrate the stage-specific necessity of Notch signaling in the emergence of hematopoietic progenitors and downstream definitive, adult-type erythroblasts. We also show that genetic or small molecule inhibition of the AHR results in the increased production of CD34+ CD45+ HSPCs while conversely, activation of the same receptor results in a block of hematopoietic cell emergence. Results presented here should have broad implications for hematopoietic stem cell transplantation and future clinical translation of iPSC-derived blood cells. Stem Cells 2018;36:1004-1019.


Asunto(s)
Hematopoyesis/fisiología , Células Madre Pluripotentes Inducidas/metabolismo , Receptores de Hidrocarburo de Aril/metabolismo , Receptores Notch/genética , Diferenciación Celular , Humanos , Transducción de Señal
11.
Am J Trop Med Hyg ; 98(3): 920-928, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29260657

RESUMEN

With an unprecedented number of displaced persons worldwide, strategies for improving the health of migrating populations are critical. United States-bound refugees undergo a required overseas medical examination to identify inadmissible conditions (e.g., tuberculosis) 2-6 months before resettlement, but it is limited in scope and may miss important, preventable infectious, chronic, or nutritional causes of morbidity. We sought to evaluate the feasibility and health impact of diagnosis and management of such conditions before travel. We offered voluntary testing for intestinal parasites, anemia, and hepatitis B virus infection, to U.S.-bound refugees from three Thailand-Burma border camps. Treatment and preventive measures (e.g., anemia and parasite treatment, vaccination) were initiated before resettlement. United States refugee health partners received overseas results and provided post-arrival medical examination findings. During July 9, 2012 to November 29, 2013, 2,004 refugees aged 0.5-89 years enrolled. Among 463 participants screened for seven intestinal parasites overseas and after arrival, helminthic infections decreased from 67% to 12%. Among 118 with positive Strongyloides-specific antibody responses, the median fluorescent intensity decreased by an average of 81% after treatment. The prevalence of moderate-to-severe anemia (hemoglobin < 10 g/dL) was halved from 14% at baseline to 7% at departure (McNemar P = 0.001). All 191 (10%) hepatitis B-infected participants received counseling and evaluation; uninfected participants were offered vaccination. This evaluation demonstrates that targeted screening, treatment, and prevention services can be conducted during the migration process to improve the health of refugees before resettlement. With more than 250 million migrants globally, this model may offer insights into healthier migration strategies.


Asunto(s)
Infecciones Bacterianas/prevención & control , Control de Enfermedades Transmisibles/métodos , Parasitosis Intestinales/prevención & control , Tamizaje Masivo/organización & administración , Refugiados , Virosis/prevención & control , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Infecciones Bacterianas/diagnóstico , Niño , Preescolar , Femenino , Humanos , Lactante , Parasitosis Intestinales/diagnóstico , Masculino , Persona de Mediana Edad , Mianmar , Tailandia , Estados Unidos , Vacunación/estadística & datos numéricos , Virosis/diagnóstico
12.
Environ Manage ; 51(2): 423-34, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23124550

RESUMEN

Implementing effective conservation requires an understanding of factors affecting deforestation and forest degradation. Previous studies have investigated factors affecting deforestation, while few studies have examined the determinants of both of deforestation and forest degradation for more than one period. To address this gap, this study examined factors influencing deforestation and forest degradation during 1989-2000 and 2000-2005 in the Popa Mountain Park, Myanmar. We applied multinomial logistic regression (MNL) using land cover maps derived from Landsat images as the dependent variables as well as spatial and biophysical factors as the independent variables. The MNL models revealed influences of the determinants on deforestation and forest degradation changes over time. For example, during 1989-2000, deforestation from closed forest was positively correlated to the distance from the park boundary and was negatively correlated with distance from villages, roads, the park circular road, slope, western aspect and elevation. On the other hand, during 2000-2005, deforestation of closed forest was positively correlated with distance from villages, roads, the park circular road, slope and western aspect, and negatively correlated with distance from the park boundary and elevation. Similar scenarios were observed for the deforestation of open forest and forest degradation of closed forest. The study also found most of the determinants influenced deforestation and forest degradation differently. The changes in determinants of deforestation and forest degradation over time might be attributable to the general decrease in resource availability and to the effect of conservation measures conducted by the park.


Asunto(s)
Monitoreo del Ambiente/métodos , Árboles , Conservación de los Recursos Naturales , Sistemas de Información Geográfica , Mianmar
13.
Lancet Infect Dis ; 10(10): 673-81, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20832366

RESUMEN

BACKGROUND: Artemisinin-combination therapy (ACT) is recommended as first-line treatment of falciparum malaria throughout the world, and fixed-dose combinations are preferred by WHO; whether a single gametocytocidal dose of primaquine should be added is unknown. We aimed to compare effectiveness of four fixed-dose ACTs and a loose tablet combination of artesunate and mefloquine, and assess the addition of a single gametocytocidal dose of primaquine. METHODS: In an open-label randomised trial in clinics in Rakhine state, Kachin state, and Shan state in Myanmar (Burma) between Dec 30, 2008, and March 20, 2009, we compared the effectiveness of all four WHO-recommended fixed-dose ACTs (artesunate-mefloquine, artesunate-amodiaquine, dihydroartemisinin-piperaquine, artemether-lumefantrine) and loose artesunate-mefloquine in Burmese adults and children. Eligible patients were those who presented to the clinics with acute uncomplicated Plasmodium falciparum malaria or mixed infection, who were older than 6 months, and who weighed more than 5 kg. Treatments were randomised in equal numbers within blocks of 50 and allocation was in sealed envelopes. All patients were also randomly assigned to receive either a single dose of primaquine 0·75 mg base/kg or not. Patients were followed up for 63 days. Treatment groups were compared by analysis of variance and multiple logistic regression. The primary outcome was the 63 day recrudescence rate. This study is registered with clinicaltrials.gov, number NCT00902811. FINDINGS: 155 patients received artesunate-amodiaquine, 162 artemether-lumefantrine, 169 artesunate-mefloquine, 161 loose artesunate-mefloquine, and 161 dihydroartemisinin-piperaquine. By day 63 of follow-up, 14 patients (9·4%; 95% CI 5·7-15·3%) on artesunate-amodiaquine had recrudescent P falciparum infections, a rate significantly higher than for artemether-lumefantrine (two patients; 1·4%; 0·3-5·3; p=0·0013), fixed-dose artesunate-mefloquine (0 patients; 0-2·3; p<0·0001), loose artesunate-mefloquine (two patients; 1·3%; 0·3-5·3; p=0·0018), and dihydroartemisinin-piperaquine (two patients 1·3%; 0·3-5·2%; p=0·0012). Hazard ratios for re-infection (95% CI) after artesunate-amodiaquine were 3·2 (1·3-8·0) compared with the two artesunate-mefloquine groups (p=0·01), 2·6 (1·0-6-0) compared with artemether-lumefantrine (p=0·04), and 2·3 (0·9-6·0) compared with dihydroartemisinin-piperaquine (p=0·08). Mixed falciparum and vivax infections were common: 129 (16%) had a mixed infection at presentation and 330 (41%) patients had one or more episodes of Plasmodium vivax infection during follow-up. The addition of a single dose of primaquine (0·75 mg/kg) reduced P falciparum gametocyte carriage substantially: rate ratio 11·9 (95% CI 7·4-20·5). All regimens were well tolerated. Adverse events were reported by 599 patients, most commonly vomiting and dizziness. Other side-effects were less common and were not related to a specific treatment. INTERPRETATION: Artesunate-amodiaquine should not be used in Myanmar, because the other ACTs are substantially more effective. Artesunate-mefloquine provided the greatest post-treatment suppression of malaria. Adding a single dose of primaquine would substantially reduce transmission potential. Vivax malaria, not recurrent falciparum malaria, is the main complication after treatment of P falciparum infections in this region. FUNDING: Médecins sans Frontières (Holland) and the Wellcome Trust Mahidol University Oxford Tropical Medicine Research Programme.


Asunto(s)
Antimaláricos/administración & dosificación , Artemisininas/administración & dosificación , Malaria Falciparum/tratamiento farmacológico , Plasmodium falciparum/efectos de los fármacos , Primaquina/administración & dosificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Quimioterapia Combinada/métodos , Femenino , Humanos , Lactante , Malaria Falciparum/complicaciones , Malaria Falciparum/epidemiología , Malaria Vivax/epidemiología , Masculino , Mefloquina/administración & dosificación , Persona de Mediana Edad , Mianmar/epidemiología , Resultado del Tratamiento , Adulto Joven
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