Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 299
Filtrar
Más filtros

Intervalo de año de publicación
1.
J Infect Dis ; 225(6): 1050-1061, 2022 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-33263735

RESUMEN

BACKGROUND: A seasonal transmission environment including seasonal variation of snail population density and human-snail contact patterns can affect the dynamics of Schistosoma infection and the success of control interventions. In projecting control outcomes, conventional modeling approaches have often ignored seasonality by using simplified intermediate-host modeling, or by restricting seasonal effects through use of yearly averaging. METHODS: We used mathematical analysis and numerical simulation to estimate the impact of seasonality on disease dynamics and control outcomes, and to evaluate whether seasonal averaging or intermediate-host reduction can provide reliable predictions of control outcomes. We also examined whether seasonality could be used as leverage in creation of effective control strategies. RESULTS: We found models that used seasonal averaging could grossly overestimate infection burden and underestimate control outcomes in highly seasonal environments. We showed that proper intraseasonal timing of control measures could make marked improvement on the long-term burden reduction for Schistosoma transmission control, and we identified the optimal timing for each intervention. Seasonal snail control, implemented alone, was less effective than mass drug administration, but could provide additive impact in reaching control and elimination targets. CONCLUSIONS: Seasonal variation makes Schistosoma transmission less sustainable and easier to control than predicted by earlier modeling studies.


Asunto(s)
Administración Masiva de Medicamentos , Schistosoma , Animales , Clima , Simulación por Computador , Humanos , Estaciones del Año
2.
J Foot Ankle Surg ; 61(2): 350-354, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34657805

RESUMEN

Concomitant syndesmotic injury occurs in 10% of ankle fractures. Anatomic reduction and maintenance of this reduction is critical in ensuring ankle stability and preventing long-term complications. This is a retrospective cohort study aimed at evaluating the mid-term radiological outcomes of syndesmotic injuries in ankle fracture patients after surgical fixation with suture button device. The study group included 33 patients. Plain radiographs including anteroposterior, lateral and mortise views of the affected ankle were performed preoperatively, postoperatively and at 3-month follow-up. Anteroposterior views were used to measure the amount of tibiofibular overlap and tibiofibular clear space. Paired Student's t test and linear model regression were performed. Between the immediate postoperative and 3-month follow-up period, there was a mean decrease in tibiofibular overlap of 0.841 (±2.07) mm (p = .0259). There was a mean increase in tibiofibular clear space of 0.621 (±1.46) mm (p = .0201). In addition, we found significant correlation between fracture type and change in tibiofibular clear space (p = .047). Our study showed that there is statistically significant widening of the syndesmosis after suture button fixation at 3-month follow-up as evidenced by reduced tibiofibular overlap and increase in tibiofibular clear space. However, they remain within the maximum threshold for acceptable syndesmotic widening of 1.5 mm. Further correlation between radiological outcomes and patient function is needed to determine clinical significance of these changes.


Asunto(s)
Fracturas de Tobillo , Traumatismos del Tobillo , Fracturas de Tobillo/diagnóstico por imagen , Fracturas de Tobillo/cirugía , Traumatismos del Tobillo/diagnóstico por imagen , Traumatismos del Tobillo/cirugía , Articulación del Tobillo/cirugía , Fijación Interna de Fracturas/efectos adversos , Humanos , Estudios Retrospectivos , Suturas , Resultado del Tratamiento
3.
Gastroenterology ; 158(1): 238-252, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31585122

RESUMEN

BACKGROUND & AIMS: We studied interactions among proteins of the carcinoembryonic antigen-related cell adhesion molecule (CEACAM) family, which interact with microbes, and transforming growth factor beta (TGFB) signaling pathway, which is often altered in colorectal cancer cells. We investigated mechanisms by which CEACAM proteins inhibit TGFB signaling and alter the intestinal microbiome to promote colorectal carcinogenesis. METHODS: We collected data on DNA sequences, messenger RNA expression levels, and patient survival times from 456 colorectal adenocarcinoma cases, and a separate set of 594 samples of colorectal adenocarcinomas, in The Cancer Genome Atlas. We performed shotgun metagenomic sequencing analyses of feces from wild-type mice and mice with defects in TGFB signaling (Sptbn1+/- and Smad4+/-/Sptbn1+/-) to identify changes in microbiota composition before development of colon tumors. CEACAM protein and its mutants were overexpressed in SW480 and HCT116 colorectal cancer cell lines, which were analyzed by immunoblotting and proliferation and colony formation assays. RESULTS: In colorectal adenocarcinomas, high expression levels of genes encoding CEACAM proteins, especially CEACAM5, were associated with reduced survival times of patients. There was an inverse correlation between expression of CEACAM genes and expression of TGFB pathway genes (TGFBR1, TGFBR2, and SMAD3). In colorectal adenocarcinomas, we also found an inverse correlation between expression of genes in the TGFB signaling pathway and genes that regulate stem cell features of cells. We found mutations encoding L640I and A643T in the B3 domain of human CEACAM5 in colorectal adenocarcinomas; structural studies indicated that these mutations would alter the interaction between CEACAM5 and TGFBR1. Overexpression of these mutants in SW480 and HCT116 colorectal cancer cell lines increased their anchorage-independent growth and inhibited TGFB signaling to a greater extent than overexpression of wild-type CEACAM5, indicating that they are gain-of-function mutations. Compared with feces from wild-type mice, feces from mice with defects in TGFB signaling had increased abundance of bacterial species that have been associated with the development of colon tumors, including Clostridium septicum, and decreased amounts of beneficial bacteria, such as Bacteroides vulgatus and Parabacteroides distasonis. CONCLUSION: We found expression of CEACAMs and genes that regulate stem cell features of cells to be increased in colorectal adenocarcinomas and inversely correlated with expression of TGFB pathway genes. We found colorectal adenocarcinomas to express mutant forms of CEACAM5 that inhibit TGFB signaling and increase proliferation and colony formation. We propose that CEACAM proteins disrupt TGFB signaling, which alters the composition of the intestinal microbiome to promote colorectal carcinogenesis.


Asunto(s)
Antígeno Carcinoembrionario/genética , Carcinogénesis/genética , Neoplasias Colorrectales/genética , Microbioma Gastrointestinal/fisiología , Transducción de Señal/genética , Animales , Bacterias/genética , Bacterias/aislamiento & purificación , Antígeno Carcinoembrionario/metabolismo , Neoplasias Colorrectales/microbiología , Neoplasias Colorrectales/mortalidad , Modelos Animales de Enfermedad , Heces/microbiología , Proteínas Ligadas a GPI/genética , Proteínas Ligadas a GPI/metabolismo , Mutación con Ganancia de Función , Regulación Neoplásica de la Expresión Génica , Células HCT116 , Humanos , Metagenómica , Ratones , Ratones Transgénicos , Dominios Proteicos/genética , Receptor Tipo I de Factor de Crecimiento Transformador beta/metabolismo , Proteína Smad4/genética , Proteína Smad4/metabolismo , Esferoides Celulares , Análisis de Supervivencia , Factor de Crecimiento Transformador beta/metabolismo
4.
PLoS Biol ; 16(12): e3000099, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30596645

RESUMEN

A personalized approach based on a patient's or pathogen's unique genomic sequence is the foundation of precision medicine. Genomic findings must be robust and reproducible, and experimental data capture should adhere to findable, accessible, interoperable, and reusable (FAIR) guiding principles. Moreover, effective precision medicine requires standardized reporting that extends beyond wet-lab procedures to computational methods. The BioCompute framework (https://w3id.org/biocompute/1.3.0) enables standardized reporting of genomic sequence data provenance, including provenance domain, usability domain, execution domain, verification kit, and error domain. This framework facilitates communication and promotes interoperability. Bioinformatics computation instances that employ the BioCompute framework are easily relayed, repeated if needed, and compared by scientists, regulators, test developers, and clinicians. Easing the burden of performing the aforementioned tasks greatly extends the range of practical application. Large clinical trials, precision medicine, and regulatory submissions require a set of agreed upon standards that ensures efficient communication and documentation of genomic analyses. The BioCompute paradigm and the resulting BioCompute Objects (BCOs) offer that standard and are freely accessible as a GitHub organization (https://github.com/biocompute-objects) following the "Open-Stand.org principles for collaborative open standards development." With high-throughput sequencing (HTS) studies communicated using a BCO, regulatory agencies (e.g., Food and Drug Administration [FDA]), diagnostic test developers, researchers, and clinicians can expand collaboration to drive innovation in precision medicine, potentially decreasing the time and cost associated with next-generation sequencing workflow exchange, reporting, and regulatory reviews.


Asunto(s)
Biología Computacional/métodos , Análisis de Secuencia de ADN/métodos , Animales , Comunicación , Biología Computacional/normas , Genoma , Genómica/métodos , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Medicina de Precisión/tendencias , Reproducibilidad de los Resultados , Análisis de Secuencia de ADN/normas , Programas Informáticos , Flujo de Trabajo
5.
Proc Natl Acad Sci U S A ; 115(4): E584-E591, 2018 01 23.
Artículo en Inglés | MEDLINE | ID: mdl-29301964

RESUMEN

Schistosomiasis is a parasitic disease that affects over 240 million people globally. To improve population-level disease control, there is growing interest in adding chemical-based snail control interventions to interrupt the lifecycle of Schistosoma in its snail host to reduce parasite transmission. However, this approach is not widely implemented, and given environmental concerns, the optimal conditions for when snail control is appropriate are unclear. We assessed the potential impact and cost-effectiveness of various snail control strategies. We extended previously published dynamic, age-structured transmission and cost-effectiveness models to simulate mass drug administration (MDA) and focal snail control interventions against Schistosoma haematobium across a range of low-prevalence (5-20%) and high-prevalence (25-50%) rural Kenyan communities. We simulated strategies over a 10-year period of MDA targeting school children or entire communities, snail control, and combined strategies. We measured incremental cost-effectiveness in 2016 US dollars per disability-adjusted life year and defined a strategy as optimally cost-effective when maximizing health gains (averted disability-adjusted life years) with an incremental cost-effectiveness below a Kenya-specific economic threshold. In both low- and high-prevalence settings, community-wide MDA with additional snail control reduced total disability by an additional 40% compared with school-based MDA alone. The optimally cost-effective scenario included the addition of snail control to MDA in over 95% of simulations. These results support inclusion of snail control in global guidelines and national schistosomiasis control strategies for optimal disease control, especially in settings with high prevalence, "hot spots" of transmission, and noncompliance to MDA.


Asunto(s)
Modelos Económicos , Esquistosomiasis/prevención & control , Caracoles , Animales , Simulación por Computador , Análisis Costo-Beneficio , Humanos , Kenia , Esquistosomiasis/economía , Esquistosomiasis/transmisión
6.
J Infect Dis ; 221(5): 796-803, 2020 02 18.
Artículo en Inglés | MEDLINE | ID: mdl-31621850

RESUMEN

BACKGROUND: Some villages, labeled "persistent hotspots (PHS)," fail to respond adequately in regard to prevalence and intensity of infection to mass drug administration (MDA) for schistosomiasis. Early identification of PHS, for example, before initiating or after 1 or 2 years of MDA could help guide programmatic decision making. METHODS: In a study with multiple rounds of MDA, data collected before the third MDA were used to predict PHS. We assessed 6 predictive approaches using data from before MDA and after 2 rounds of annual MDA from Kenya and Tanzania. RESULTS: Generalized linear models with variable selection possessed relatively stable performance compared with tree-based methods. Models applied to Kenya data alone or combined data from Kenya and Tanzania could reach over 80% predictive accuracy, whereas predicting PHS for Tanzania was challenging. Models developed from one country and validated in another failed to achieve satisfactory performance. Several Year-3 variables were identified as key predictors. CONCLUSIONS: Statistical models applied to Year-3 data could help predict PHS and guide program decisions, with infection intensity, prevalence of heavy infections (≥400 eggs/gram of feces), and total prevalence being particularly important factors. Additional studies including more variables and locations could help in developing generalizable models.


Asunto(s)
Antihelmínticos/uso terapéutico , Administración Masiva de Medicamentos/métodos , Praziquantel/uso terapéutico , Schistosoma mansoni/aislamiento & purificación , Esquistosomiasis mansoni/tratamiento farmacológico , Esquistosomiasis mansoni/epidemiología , Animales , Niño , Estudios de Factibilidad , Heces/parasitología , Femenino , Humanos , Kenia/epidemiología , Masculino , Modelos Estadísticos , Enfermedades Desatendidas/tratamiento farmacológico , Enfermedades Desatendidas/epidemiología , Enfermedades Desatendidas/parasitología , Prevalencia , Esquistosomiasis mansoni/parasitología , Esquistosomiasis mansoni/prevención & control , Tanzanía/epidemiología
7.
J Infect Dis ; 221(Suppl 5): S525-S530, 2020 06 11.
Artículo en Inglés | MEDLINE | ID: mdl-31829414

RESUMEN

The World Health Organization (WHO) has set elimination as a public health problem (EPHP) as a goal for schistosomiasis. As the WHO treatment guidelines for schistosomiasis are currently under revision, we investigate whether school-based or community-wide treatment strategies are required for achieving the EPHP goal. In low- to moderate-transmission settings with good school enrolment, we find that school-based treatment is sufficient for achieving EPHP. However, community-wide treatment is projected to be necessary in certain high-transmission settings as well as settings with low school enrolment. Hence, the optimal treatment strategy depends on setting-specific factors such as the species present, prevalence prior to treatment, and the age profile of infection.


Asunto(s)
Administración Masiva de Medicamentos/normas , Schistosoma haematobium , Schistosoma mansoni , Esquistosomiasis Urinaria/tratamiento farmacológico , Esquistosomiasis mansoni/tratamiento farmacológico , Adolescente , Adulto , Anciano , Animales , Niño , Preescolar , Servicios de Salud Comunitaria , Humanos , Persona de Mediana Edad , Modelos Biológicos , Guías de Práctica Clínica como Asunto , Salud Pública , Esquistosomiasis Urinaria/epidemiología , Esquistosomiasis mansoni/epidemiología , Adulto Joven
8.
Malar J ; 19(1): 190, 2020 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-32448228

RESUMEN

BACKGROUND: Prevention and treatment of malaria during pregnancy is crucial in dealing with maternal mortality and adverse fetal outcomes. The World Health Organization recommendation to treat all pregnant women with sulfadoxine-pyrimethamine (SP) through antenatal care structures was implemented in Kenya in the year 1998, but concerns about its effectiveness in preventing malaria in pregnancy has arisen due to the spread of SP resistant parasites. This study aimed to determine the prevalence of SP resistance markers in Plasmodium falciparum parasites isolated from pregnant women seeking antenatal care at Msambweni County Referral Hospital, located in coastal Kenya, between the year 2013 and 2015. METHODS: This hospital-based study included 106 malaria positive whole blood samples for analysis of SP resistance markers within the Pfdhfr gene (codons 51, 59 and 108) and Pfdhps gene (codons 437 and 540). The venous blood collected from all pregnant women was tested for malaria via light microscopy, then the malaria positive samples were separated into plasma and red cells and stored in a - 86° freezer for further studies. Archived red blood cells were processed for molecular characterization of SP resistance markers within the Pfdhfr and Pfdhps genes using real time PCR platform and Sanger sequencing. RESULTS: All samples had at least one mutation in the genes associated with drug resistance; polymorphism prevalence of Pfdhfr51I, 59R and 108N was at 88.7%, 78.3% and 93.4%, respectively, while Pfdhps polymorphism accounted for 94.3% and 91.5% at 437G and 540E, respectively. Quintuple mutations (at all the five codons) conferring total SP resistance had the highest prevalence of 85.8%. Quadruple mutations were observed at a frequency of 10.4%, and 24.5% had a mixed outcome of both wildtype and mutant genotypes in the genes of interest. CONCLUSION: The data suggest a high prevalence of P. falciparum genetic variations conferring resistance to SP among pregnant women, which may explain reduced efficacy of IPTp treatment in Kenya. There is need for extensive SP resistance profiling in Kenya to inform IPTp drug choices for successful malaria prevention during pregnancy.


Asunto(s)
Antimaláricos/farmacología , Resistencia a Medicamentos/genética , Plasmodium falciparum/genética , Proteínas Protozoarias/genética , Pirimetamina/farmacología , Sulfadoxina/farmacología , Tetrahidrofolato Deshidrogenasa/genética , Adulto , Antimaláricos/uso terapéutico , Combinación de Medicamentos , Femenino , Marcadores Genéticos , Humanos , Kenia/epidemiología , Malaria Falciparum/epidemiología , Mutación , Embarazo , Prevalencia , Proteínas Protozoarias/metabolismo , Pirimetamina/uso terapéutico , Sulfadoxina/uso terapéutico , Tetrahidrofolato Deshidrogenasa/metabolismo , Adulto Joven
9.
BMC Pediatr ; 20(1): 208, 2020 05 12.
Artículo en Inglés | MEDLINE | ID: mdl-32398049

RESUMEN

BACKGROUND: Chronic malnutrition, often measured as stunted growth, is an understudied global health problem. Though poor nutritional intake has been linked to stunted growth, there is evidence suggesting environmental exposures may have a significant role in its occurrence. Here, we characterize the non-nutritional prenatal and postnatal factors that contribute to early childhood stunted growth in rural coastal Kenya. METHODS: Overall, 232 women and 244 children from a 2012-2015 maternal-child cohort in Msambweni, Kenya were included. Women were tested for parasitic infections during the prenatal period and at the time of delivery. Children were tested for parasitic infections and assessed for stunted growth using height-for-age Z-scores (HAZ) at 6-month intervals after birth. Socioeconomic status (SES) was evaluated using both a simplified water, asset, maternal education, and income (WAMI) index and a principal component analysis (PCA) asset score. Multivariate logistic regression analysis was used to determine the relative influence of prenatal and postnatal factors on the occurrence of stunted growth. RESULTS: Of the 244 children (ages 6-37 months), 60 (25%) were stunted at the study endpoint. 179 mothers (77%) had at least one parasitic infection during pregnancy and 94 children (38%) had at least one parasitic infection during the study period. There was no significant association between maternal parasitic infection and child stunted growth (p = 1.00). SES as determined using the WAMI index was not associated with HAZ in linear regression analysis (p = 0.307), however, the PCA asset score was (p = 0.048). Multivariate logistic regression analysis identified low birth weight (AOR: 3.24, 95% CI: [1.38, 7.57]) and child parasitic infectious disease burden (AOR: 1.41, 95% CI: [1.05, 1.95]) as independent predictors of stunted growth, though no significant association was identified with PCA asset score (AOR: 0.98, 95% CI: [0.88, 1.10]). CONCLUSIONS: Stunted growth remains highly prevalent in rural Kenya, with low birth weight and child parasitic infectious disease burden demonstrated to be significantly associated with this indicator of chronic malnutrition. These results emphasize the multifaceted nature of stunted growth and the need to address both the prenatal and postnatal environmental factors that contribute to this problem.


Asunto(s)
Estatura , Trastornos del Crecimiento , Niño , Preescolar , Estudios Transversales , Femenino , Trastornos del Crecimiento/epidemiología , Trastornos del Crecimiento/etiología , Humanos , Lactante , Kenia/epidemiología , Embarazo , Población Rural
10.
Foot Ankle Surg ; 26(6): 614-623, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31439502

RESUMEN

BACKGROUND: We aim to provide an evidence-based literature review of salvage arthrodesis for failed first metatarsophalangeal joint arthroplasty with a network meta-analysis. METHODS: A search of PubMed, Embase and Cochrane databases was conducted in December 2016 which identified 12 relevant articles out of 340 articles assessing the efficacy of salvage arthrodesis for failed joint arthroplasty of the first metatarsophalangeal joint. The 12 studies were assigned a level of evidence (I-V) and interventions were graded a level of recommendation (A-C, I) in support of or against the treatment modality. RESULTS: There is fair evidence (grade B) to support salvage arthrodesis with structural bone graft. There is poor evidence (grade C) for salvage arthrodesis without bone graft. There was no good evidence (grade A) to recommend either intervention. Meta-analysis showed that salvage arthrodesis resulted in improved functional outcome over time. CONCLUSIONS: Salvage arthrodesis showed good bone union rates and patient satisfaction. LEVEL OF CLINICAL EVIDENCE: III - Systematic Review of Level III studies.


Asunto(s)
Artrodesis , Hallux Rigidus/cirugía , Articulación Metatarsofalángica/cirugía , Terapia Recuperativa , Artroplastia/efectos adversos , Humanos , Osteogénesis , Satisfacción del Paciente
11.
Nano Lett ; 18(6): 3586-3592, 2018 06 13.
Artículo en Inglés | MEDLINE | ID: mdl-29767979

RESUMEN

Due to the substantial increase in power density, thermal interface resistance that can constitute more than 50% of the total thermal resistance has generally become a bottleneck for thermal management in electronics. However, conventional thermal interface materials (TIMs) such as solder, epoxy, gel, and grease cannot fulfill the requirements of electronics for high-power and long-term operation. Here, we demonstrate a high-performance TIM consisting of a heterogeneous copper-tin nanowire array, which we term "supersolder" to emulate the role of conventional solders in bonding various surfaces. The supersolder is ultracompliant with a shear modulus 2-3 orders of magnitude lower than traditional solders and can reduce the thermal resistance by two times as compared with the state-of-the-art TIMs. This supersolder also exhibits excellent long-term reliability with >1200 thermal cycles over a wide temperature range. By resolving this critical thermal bottleneck, the supersolder enables electronic systems, ranging from microelectronics and portable electronics to massive data centers, to operate at lower temperatures with higher power density and reliability.

12.
J Infect Dis ; 217(9): 1426-1434, 2018 04 11.
Artículo en Inglés | MEDLINE | ID: mdl-29390149

RESUMEN

Background: Antenatal exposure to parasites can affect infants' subsequent responses to vaccination. The present study investigated how maternal prenatal infections and newborns' antiparasite cytokine profiles relate to immunoglobulin G (IgG) responses to standard vaccination during infancy. Methods: A total of 450 Kenyan women were tested for parasitic infections during pregnancy. Their newborns' responses to Plasmodium falciparum, schistosome, and filaria antigens were assessed in cord blood lymphocytes. Following standard neonatal vaccination, this infant cohort was followed biannually to age 30 months for measurement of circulating IgG levels against Haemophilus influenzae b (Hib), diphtheria toxoid (DT), hepatitis B virus (HBV), and tetanus toxoid. Results: Trajectories of postvaccination IgG levels were classified by functional principal component (PC) analysis to assess each child's response profile. Two main components, PC1, reflecting height of response over time, and PC2, reflecting crossover from high to low responses or from low to high responses, were identified. Cord blood cytokine responses to schistosome and filarial antigens showed a significant association between augmented antihelminth interleukin 10 and reduced antibody levels, particularly to DT and HBV, and a more rapid postvaccination decline in circulating IgG levels against Hib. Conclusion: Antenatal sensitization to schistosomiasis or filariasis and related production of antiparasite interleukin 10 at birth are associated with reduced antivaccine IgG levels in infancy, with possibly impaired protection.


Asunto(s)
Sangre Fetal , Inmunoglobulina G/sangre , Interleucina-10/sangre , Complicaciones Parasitarias del Embarazo , Vacunas/inmunología , Adulto , Envejecimiento , Anticuerpos Antibacterianos/sangre , Anticuerpos Antivirales/sangre , Biomarcadores , Citocinas/genética , Citocinas/metabolismo , Femenino , Regulación de la Expresión Génica , Humanos , Lactante , Recién Nacido , Kenia , Embarazo , Análisis de Componente Principal , Factores de Riesgo
13.
Clin Infect Dis ; 66(suppl_4): S245-S252, 2018 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-29860290

RESUMEN

Background: Schistosomiasis remains an endemic parasitic disease affecting millions of people around the world. The World Health Organization (WHO) has set goals of controlling morbidity to be reached by 2020, along with elimination as a public health problem in certain regions by 2025. Mathematical models of parasite transmission and treatment impact have been developed to assist in controlling the morbidity caused by schistosomiasis. These models can inform and guide implementation policy for mass drug administration programs, and help design monitoring and evaluation activities. Methods: We use these models to predict whether the guidelines set by the WHO are on track for achieving their 2020 goal for the control of morbidity, specifically for Schistosoma mansoni. We examine whether programmatic adaptations; namely increases in treatment coverage and/or expansion to adult inclusion in treatment, will improve the likelihood of reaching the WHO goals. Results: We find that in low-prevalence settings, the goals are likely to be attainable under current WHO guidelines, but in moderate to high-prevalence settings, the goals are less likely to be achieved unless treatment coverage is increased and expanded to at least 85% for school-aged children and 40% for adults. Conclusions: To improve the likelihood of reaching the WHO goals, programmatic adaptations are required, particularly for moderate- to high-prevalence settings. Furthermore, improvements in adherence to treatment, potential development of candidate vaccines, and enhanced snail control and WASH (water, sanitation, and hygiene) measures will all assist in achieving the goals.


Asunto(s)
Enfermedades Endémicas/prevención & control , Modelos Teóricos , Guías de Práctica Clínica como Asunto , Salud Pública , Esquistosomiasis/epidemiología , Animales , Erradicación de la Enfermedad , Objetivos , Humanos , Higiene , Administración Masiva de Medicamentos , Morbilidad , Prevalencia , Saneamiento , Esquistosomiasis/tratamiento farmacológico , Esquistosomiasis/prevención & control , Esquistosomiasis/transmisión , Organización Mundial de la Salud
14.
PLoS Biol ; 13(7): e1002192, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26158466

RESUMEN

To provide tight spatiotemporal signaling control, the cyclic adenosine monophosphate (cAMP)-dependent protein kinase (PKA) holoenzyme typically nucleates a macromolecular complex or a "PKA signalosome." Using the RIIß holoenzyme as a prototype, we show how autophosphorylation/dephosphorylation of the RIIß subunit, as well as cAMP and metal ions, contribute to the dynamics of PKA signaling. While we showed previously that the RIIß holoenzyme could undergo a single turnover autophosphorylation with adenosine triphosphate and magnesium (MgATP) and trap both products in the crystal lattice, we asked here whether calcium could trap an ATP:RIIß holoenzyme since the RIIß holoenzyme is located close to ion channels. The 2.8Å structure of an RIIßp2:C2:(Ca2ADP)2 holoenzyme, supported by biochemical and biophysical data, reveals a trapped single phosphorylation event similar to MgATP. Thus, calcium can mediate a single turnover event with either ATP or adenosine-5'-(ß,γ-imido)triphosphate (AMP-PNP), even though it cannot support steady-state catalysis efficiently. The holoenzyme serves as a "product trap" because of the slow off-rate of the pRIIß subunit, which is controlled by cAMP, not by phosphorylation of the inhibitor site. By quantitatively defining the RIIß signaling cycle, we show that release of pRIIß in the presence of cAMP is reduced by calcium, whereas autophosphorylation at the phosphorylation site (P-site) inhibits holoenzyme reassociation with the catalytic subunit. Adding a single phosphoryl group to the preformed RIIß holoenzyme thus creates a signaling cycle in which phosphatases become an essential partner. This previously unappreciated molecular mechanism is an integral part of PKA signaling for type II holoenzymes.


Asunto(s)
Subunidad RIIbeta de la Proteína Quinasa Dependiente de AMP Cíclico/metabolismo , Adenosina Trifosfato/metabolismo , Animales , Calcio/metabolismo , Catálisis , AMP Cíclico/metabolismo , Escherichia coli , Células HeLa , Holoenzimas/metabolismo , Humanos , Magnesio/metabolismo , Ratones , Células 3T3 NIH , Monoéster Fosfórico Hidrolasas/metabolismo , Fosforilación , Ratas
15.
Alcohol Clin Exp Res ; 41(10): 1775-1782, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28905397

RESUMEN

BACKGROUND: The question of whether underage youth are disproportionately exposed to alcohol advertising lies at the heart of the public health debate about whether restrictions on alcohol advertising are warranted. The aim of this study was to determine whether alcohol brands popular among underage (ages 12 to 20 years) drinkers ("underage brands") are more likely than others ("other brands") to advertise in magazines with high underage readerships. METHODS: We analyze the advertising of 680 alcohol brands in 49 magazines between 2006 and 2011. Using a random effects probit model, we examine the relationship between a magazine's underage readership and the probability of an underage or other brand advertising in a magazine, controlling for young adult (ages 21 to 29 years) and total readerships, advertising costs and expenditures, and readership demographics. RESULTS: We find that underage brands are more likely than other brands to advertise in magazines with a higher percentage of underage readers. Holding all other variables constant at their sample means, the probability of an "other" brand advertising in a magazine remains essentially constant over the range of underage readership from 0.010 (95% confidence interval [CI], 0.007 to 0.013) at 5% to 0.012 (95% CI, 0.008 to 0.016) at 35%. In contrast, the probability of an underage brand advertising nearly quadruples, ranging from 0.025 (95% CI, 0.015 to 0.035) to 0.096 (95% CI, 0.057 to 0.135), where underage brands are 7.90 (95% CI, 3.89 to 11.90) times more likely than other brands to advertise. CONCLUSIONS: Alcohol brands popular among underage drinkers are more likely than other brands to advertise in magazines with high underage readerships, resulting in the disproportionate exposure of underage youth. Current voluntary advertising industry guidelines are not adequate to protect underage youth from high and disproportionate exposure to alcohol advertising in magazines. To limit advertising exposure among underage youth, policy makers may want to consider regulation of alcohol advertising in magazines.


Asunto(s)
Publicidad/tendencias , Bebidas Alcohólicas , Publicaciones Periódicas como Asunto/tendencias , Salud Pública/tendencias , Consumo de Alcohol en Menores/psicología , Consumo de Alcohol en Menores/tendencias , Adolescente , Adulto , Publicidad/economía , Publicidad/métodos , Factores de Edad , Bebidas Alcohólicas/economía , Niño , Femenino , Humanos , Masculino , Publicaciones Periódicas como Asunto/economía , Salud Pública/métodos , Consumo de Alcohol en Menores/economía , Adulto Joven
16.
BMC Infect Dis ; 17(1): 652, 2017 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-28962552

RESUMEN

BACKGROUND: The Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) focus is on randomized trials of different approaches to mass drug administration (MDA) in endemic countries in Africa. Because their studies provided an opportunity to evaluate the effects of mass treatment on Schistosoma-associated morbidity, nested cohort studies were developed within SCORE's intervention trials to monitor changes in a suite of schistosomiasis disease outcomes. This paper describes the process SCORE used to select markers for prospective monitoring and the baseline prevalence of these morbidities in four parallel cohort studies. METHODS: In July 2009, SCORE hosted a discussion of the potential impact of MDA on morbidities due to Schistosoma infection that might be measured in the context of multi-year control. Candidate markers were reviewed and selected for study implementation. Baseline data were then collected from cohorts of children in four country studies: two in high endemic S. mansoni sites (Kenya and Tanzania), and two in high endemic S. haematobium sites (Niger and Mozambique), these cohorts to be followed prospectively over 5 years. RESULTS: At baseline, 62% of children in the S. mansoni sites had detectable eggs in their stool, and 10% had heavy infections (≥ 400 eggs/g feces). Heavy S. mansoni infections were found to be associated with increased baseline risk of anemia, although children with moderate or heavy intensity infections had lower risk of physical wasting. Prevalence of egg-positive infection in the combined S. haematobium cohorts was 27%, with 5% of individuals having heavy infection (≥50 eggs/10 mL urine). At baseline, light intensity S. haematobium infection was associated with anemia and with lower scores in the social domain of health-related quality-of-life (HRQoL) assessed by Pediatric Quality of Life Inventory. CONCLUSIONS: Our consensus on practical markers of Schistosoma-associated morbidity indicated that height, weight, hemoglobin, exercise tolerance, HRQoL, and ultrasound abnormalities could be used as reference points for gauging treatment impact. Data collected over five years of program implementation will provide guidance for future evaluation of morbidity control in areas endemic for schistosomiasis. TRIAL REGISTRATION: These cohort studies are registered and performed in conjunction with the International Standard Randomised Controlled Trial Registry trials ISRCTN16755535 , ISRCTN14117624 , ISRCTN95819193 , and ISRCTN32045736 .


Asunto(s)
Antihelmínticos/uso terapéutico , Esquistosomiasis Urinaria/tratamiento farmacológico , Esquistosomiasis mansoni/tratamiento farmacológico , Anemia/tratamiento farmacológico , Anemia/etiología , Animales , Niño , Estudios de Cohortes , Heces/parasitología , Humanos , Kenia/epidemiología , Masculino , Morbilidad , Mozambique/epidemiología , Niger/epidemiología , Prevalencia , Calidad de Vida , Schistosoma haematobium/patogenicidad , Schistosoma mansoni/patogenicidad , Esquistosomiasis Urinaria/epidemiología , Esquistosomiasis mansoni/epidemiología , Tanzanía/epidemiología
17.
Parasitology ; 144(12): 1613-1623, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28245890

RESUMEN

Early in the history of schistosomiasis research, children under 5 years of age were known to be infected. Although this problem was recognized over 100 years ago, insufficient action has been taken to address this issue. Under current policy, such infected children only receive their first antiparasitic treatment (praziquantel - PZQ) upon entry into primary school as current mass drug administration programmes typically target school-aged children. For many infected children, they will wait up to 6 years before receiving their first medication and significant schistosomiasis-related morbidity may have already established. This inequity would not be accepted for other diseases. To unveil some of the reasons behind this neglect, it is paramount to understand the intricate historical relationship between schistosomiasis and British Imperial medicine, to underline its lasting influence on today's public health priorities. This review presents a perspective on the historical neglect of paediatric schistosomiasis, focusing on important gaps that persist from the early days after discovery of this parasite. Looking to end this inequity, we address several issues that need to be overcome to move forward towards the lasting success of schistosomiasis control and elimination efforts.


Asunto(s)
Salud Pública/historia , Esquistosomiasis/historia , Medicina Tropical/historia , Niño , Preescolar , Colonialismo , Historia del Siglo XX , Humanos , Esquistosomiasis/parasitología , Esquistosomiasis/prevención & control , Reino Unido
18.
Biochem J ; 473(4): 509-23, 2016 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-26635352

RESUMEN

Atypical protein kinase C (aPKC) isoenzymes are key modulators of insulin signalling, and their dysfunction correlates with insulin-resistant states in both mice and humans. Despite the engaged interest in the importance of aPKCs to type 2 diabetes, much less is known about the molecular mechanisms that govern their cellular functions than for the conventional and novel PKC isoenzymes and the functionally-related protein kinase B (Akt) family of kinases. Here we show that aPKC is constitutively phosphorylated and, using a genetically-encoded reporter for PKC activity, basally active in cells. Specifically, we show that phosphorylation at two key regulatory sites, the activation loop and turn motif, of the aPKC PKCζ in multiple cultured cell types is constitutive and independently regulated by separate kinases: ribosome-associated mammalian target of rapamycin complex 2 (mTORC2) mediates co-translational phosphorylation of the turn motif, followed by phosphorylation at the activation loop by phosphoinositide-dependent kinase-1 (PDK1). Live cell imaging reveals that global aPKC activity is constitutive and insulin unresponsive, in marked contrast to the insulin-dependent activation of Akt monitored by an Akt-specific reporter. Nor does forced recruitment to phosphoinositides by fusing the pleckstrin homology (PH) domain of Akt to the kinase domain of PKCζ alter either the phosphorylation or activity of PKCζ. Thus, insulin stimulation does not activate PKCζ through the canonical phosphatidylinositol-3,4,5-triphosphate-mediated pathway that activates Akt, contrasting with previous literature on PKCζ activation. These studies support a model wherein an alternative mechanism regulates PKCζ-mediated insulin signalling that does not utilize conventional activation via agonist-evoked phosphorylation at the activation loop. Rather, we propose that scaffolding near substrates drives the function of PKCζ.


Asunto(s)
Fosfatos de Fosfatidilinositol/metabolismo , Proteína Quinasa C/metabolismo , Proteínas Quinasas Dependientes de 3-Fosfoinosítido/genética , Proteínas Quinasas Dependientes de 3-Fosfoinosítido/metabolismo , Secuencia de Aminoácidos , Animales , Biocatálisis , Células Cultivadas , Insulina/farmacología , Diana Mecanicista del Complejo 2 de la Rapamicina , Ratones , Ratones Transgénicos , Datos de Secuencia Molecular , Complejos Multiproteicos/metabolismo , Fosforilación , Conformación Proteica , Proteína Quinasa C/química , Serina-Treonina Quinasas TOR/metabolismo
19.
J Biol Chem ; 290(36): 21845-56, 2015 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-26187466

RESUMEN

Atypical protein kinase C (aPKC) enzymes signal on protein scaffolds, yet how they are maintained in an active conformation on scaffolds is unclear. A myristoylated peptide based on the autoinhibitory pseudosubstrate fragment of the atypical PKCζ, zeta inhibitory peptide (ZIP), has been extensively used to inhibit aPKC activity; however, we have previously shown that ZIP does not inhibit the catalytic activity of aPKC isozymes in cells (Wu-Zhang, A. X., Schramm, C. L., Nabavi, S., Malinow, R., and Newton, A. C. (2012) J. Biol. Chem. 287, 12879-12885). Here we sought to identify a bona fide target of ZIP and, in so doing, unveiled a novel mechanism by which aPKCs are maintained in an active conformation on a protein scaffold. Specifically, we used protein-protein interaction network analysis, structural modeling, and protein-protein docking to predict that ZIP binds an acidic surface on the Phox and Bem1 (PB1) domain of p62, an interaction validated by peptide array analysis. Using a genetically encoded reporter for PKC activity fused to the p62 scaffold, we show that ZIP inhibits the activity of wild-type aPKC, but not a construct lacking the pseudosubstrate. These data support a model in which the pseudosubstrate of aPKCs is tethered to the acidic surface on p62, locking aPKC in an open, signaling-competent conformation. ZIP competes for binding to the acidic surface, resulting in displacement of the pseudosubstrate of aPKC and re-engagement in the substrate-binding cavity. This study not only identifies a cellular target for ZIP, but also unveils a novel mechanism by which scaffolded aPKC is maintained in an active conformation.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas Gestacionales/metabolismo , Proteína Quinasa C/metabolismo , Proteínas Adaptadoras Transductoras de Señales/química , Proteínas Adaptadoras Transductoras de Señales/genética , Secuencia de Aminoácidos , Animales , Sitios de Unión , Unión Competitiva , Western Blotting , Células COS , Chlorocebus aethiops , Transferencia Resonante de Energía de Fluorescencia , Células HEK293 , Humanos , Isoenzimas/química , Isoenzimas/genética , Isoenzimas/metabolismo , Modelos Moleculares , Datos de Secuencia Molecular , Proteínas Gestacionales/química , Unión Proteica , Conformación Proteica , Proteína Quinasa C/química , Proteína Quinasa C/genética , Estructura Terciaria de Proteína , Receptores AMPA/genética , Receptores AMPA/metabolismo , Proteína Sequestosoma-1 , Electricidad Estática
20.
FASEB J ; 29(5): 1859-68, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25630970

RESUMEN

Bicuspid aortic valves calcify at a significantly higher rate than normal aortic valves, a process that involves increased inflammation. Because we have previously found that bicuspid aortic valve experience greater stretch, we investigated the potential connection between stretch and inflammation in human aortic valve interstitial cells (AVICs). Microarray, quantitative PCR (qPCR), and protein assays performed on AVICs exposed to cyclic stretch showed that stretch was sufficient to increase expression of interleukin and metalloproteinase family members by more than 1.5-fold. Conditioned medium from stretched AVICs was sufficient to activate leukocytes. microRNA sequencing and qPCR experiments demonstrated that miR-148a-3p was repressed in both stretched AVICs (43% repression) and, as a clinical correlate, human bicuspid aortic valves (63% reduction). miR-148a-3p was found to be a novel repressor of IKBKB based on data from qPCR, luciferase, and Western blot experiments. Furthermore, increasing miR-148a-3p levels in AVICs was sufficient to decrease NF-κB (nuclear factor kappa-light-chain-enhancer of activated B cells) signaling and NF-κB target gene expression. Our data demonstrate that stretch-mediated activation of inflammatory pathways is at least partly the result of stretch-repression of miR-148a-3p and a consequent failure to repress IKBKB. To our knowledge, we are the first to report that cyclic stretch of human AVICs activates inflammatory genes in a tissue-autonomous manner via a microRNA that regulates a central inflammatory pathway.


Asunto(s)
Válvula Aórtica/anomalías , Biomarcadores/metabolismo , Enfermedades de las Válvulas Cardíacas/metabolismo , Quinasa I-kappa B/metabolismo , Inflamación/genética , MicroARNs/genética , FN-kappa B/metabolismo , Válvula Aórtica/inmunología , Válvula Aórtica/metabolismo , Enfermedad de la Válvula Aórtica Bicúspide , Western Blotting , Diferenciación Celular , Proliferación Celular , Células Cultivadas , Ensayo de Inmunoadsorción Enzimática , Perfilación de la Expresión Génica , Enfermedades de las Válvulas Cardíacas/inmunología , Humanos , Quinasa I-kappa B/genética , Inflamación/inmunología , Inflamación/patología , Monocitos/citología , Monocitos/metabolismo , FN-kappa B/genética , Análisis de Secuencia por Matrices de Oligonucleótidos , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Estrés Fisiológico
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA