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1.
Ann Intern Med ; 166(1): 9-17, 2017 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-27750294

RESUMEN

Background: Non-Hodgkin lymphoma (NHL) is the most common AIDS-defining condition in the era of antiretroviral therapy (ART). Whether chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) infection promote NHL in HIV-infected patients is unclear. Objective: To investigate whether chronic HBV and HCV infection are associated with increased incidence of NHL in HIV-infected patients. Design: Cohort study. Setting: 18 of 33 cohorts from the Collaboration of Observational HIV Epidemiological Research Europe (COHERE). Patients: HIV-infected patients with information on HBV surface antigen measurements and detectable HCV RNA, or a positive HCV antibody test result if HCV RNA measurements were not available. Measurements: Time-dependent Cox models to assess risk for NHL in treatment-naive patients and those initiating ART, with inverse probability weighting to control for informative censoring. Results: A total of 52 479 treatment-naive patients (1339 [2.6%] with chronic HBV infection and 7506 [14.3%] with HCV infection) were included, of whom 40 219 (77%) later started ART. The median follow-up was 13 months for treatment-naive patients and 50 months for those receiving ART. A total of 252 treatment-naive patients and 310 treated patients developed NHL, with incidence rates of 219 and 168 cases per 100 000 person-years, respectively. The hazard ratios for NHL with HBV and HCV infection were 1.33 (95% CI, 0.69 to 2.56) and 0.67 (CI, 0.40 to 1.12), respectively, in treatment-naive patients and 1.74 (CI, 1.08 to 2.82) and 1.73 (CI, 1.21 to 2.46), respectively, in treated patients. Limitation: Many treatment-naive patients later initiated ART, which limited the study of the associations of chronic HBV and HCV infection with NHL in this patient group. Conclusion: In HIV-infected patients receiving ART, chronic co-infection with HBV and HCV is associated with an increased risk for NHL. Primary Funding Source: European Union Seventh Framework Programme.


Asunto(s)
Infecciones por VIH/complicaciones , Hepatitis B Crónica/complicaciones , Hepatitis C Crónica/complicaciones , Linfoma no Hodgkin/complicaciones , Adulto , Fármacos Anti-VIH/uso terapéutico , Biomarcadores/sangre , Estudios de Cohortes , Femenino , Infecciones por VIH/tratamiento farmacológico , Anticuerpos Antihepatitis/sangre , Antígenos del Núcleo de la Hepatitis B/inmunología , Antígenos de Superficie de la Hepatitis B/sangre , Antígenos de Superficie de la Hepatitis B/inmunología , Hepatitis B Crónica/diagnóstico , Hepatitis C/inmunología , Hepatitis C Crónica/diagnóstico , Humanos , Inmunoglobulina G/sangre , Linfoma no Hodgkin/mortalidad , Masculino , ARN Viral/sangre , Factores de Riesgo
2.
Clin Infect Dis ; 63(9): 1245-1253, 2016 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-27578823

RESUMEN

BACKGROUND: The burden of Kaposi sarcoma (KS) in human immunodeficiency virus (HIV)-infected children and adolescents on combination antiretroviral therapy (cART) has not been compared globally. METHODS: We analyzed cohort data from the International Epidemiologic Databases to Evaluate AIDS and the Collaboration of Observational HIV Epidemiological Research in Europe. We included HIV-infected children aged <16 years at cART initiation from 1996 onward. We used Cox models to calculate hazard ratios (HRs), adjusted for region and origin, sex, cART start year, age, and HIV/AIDS stage at cART initiation. RESULTS: We included 24 991 children from eastern Africa, southern Africa, Europe and Asia; 26 developed KS after starting cART. Incidence rates per 100 000 person-years (PYs) were 86 in eastern Africa (95% confidence interval [CI], 55-133), 11 in southern Africa (95% CI, 4-35), and 81 (95% CI, 26-252) in children of sub-Saharan African (SSA) origin in Europe. The KS incidence rates were 0/100 000 PYs in children of non-SSA origin in Europe (95% CI, 0-50) and in Asia (95% CI, 0-27). KS risk was lower in girls than in boys (adjusted HR [aHR], 0.3; 95% CI, .1-.9) and increased with age (10-15 vs 0-4 years; aHR, 3.4; 95% CI, 1.2-10.1) and advanced HIV/AIDS stage (CDC stage C vs A/B; aHR, 2.4; 95% CI, .8-7.3) at cART initiation. CONCLUSIONS: HIV-infected children from SSA but not those from other regions, have a high risk of developing KS after cART initiation. Early cART initiation in these children might reduce KS risk.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/complicaciones , Sarcoma de Kaposi/epidemiología , Adolescente , África del Sur del Sahara/epidemiología , Asia/epidemiología , Niño , Preescolar , Estudios de Cohortes , Quimioterapia Combinada , Europa (Continente)/epidemiología , Femenino , Infecciones por VIH/tratamiento farmacológico , Humanos , Incidencia , Lactante , Recién Nacido , Masculino , Medición de Riesgo , Sarcoma de Kaposi/complicaciones , Tiempo de Tratamiento
3.
BMC Infect Dis ; 16(1): 654, 2016 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-27825316

RESUMEN

BACKGROUND: Few studies have evaluated the impact of pre-treatment drug resistance (PDR) on response to combination antiretroviral treatment (cART) in children. The objective of this joint EuroCoord-CHAIN-EPPICC/PENTA project was to assess the prevalence of PDR mutations and their association with virological outcome in the first year of cART in children. METHODS: HIV-infected children <18 years initiating cART between 1998 and 2008 were included if having at least one genotypic resistance test prior to cART initiation. We used the World Health Organization 2009 resistance mutation list and Stanford algorithm to infer resistance to prescribed drugs. Time to virological failure (VF) was defined as the first of two consecutive HIV-RNA > 500 copies/mL after 6 months cART and was assessed by Cox proportional hazards models. All models were adjusted for baseline demographic, clinical, immunology and virology characteristics and calendar period of cART start and initial cART regimen. RESULTS: Of 476 children, 88 % were vertically infected. At cART initiation, median (interquartile range) age was 6.6 years (2.1-10.1), CD4 cell count 297 cells/mm3 (98-639), and HIV-RNA 5.2 log10copies/mL (4.7-5.7). Of 37 children (7.8 %, 95 % confidence interval (CI), 5.5-10.6) harboring a virus with ≥1 PDR mutations, 30 children had a virus resistant to ≥1 of the prescribed drugs. Overall, the cumulative Kaplan-Meier estimate for virological failure was 19.8 % (95 %CI, 16.4-23.9). Cumulative risk for VF tended to be higher among children harboring a virus with PDR and resistant to ≥1 drug prescribed than among those receiving fully active cART: 32.1 % (17.2-54.8) versus 19.4 % (15.9-23.6) (P = 0.095). In multivariable analysis, age was associated with a higher risk of VF with a 12 % reduced risk per additional year (HR 0.88; 95 %CI, 0.82-0.95; P < 0.001). CONCLUSIONS: PDR was not significantly associated with a higher risk of VF in children in the first year of cART. The risk of VF decreased by 12 % per additional year at treatment initiation which may be due to fading of PDR mutations over time. Lack of appropriate formulations, in particular for the younger age group, may be an important determinant of virological failure.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Farmacorresistencia Viral/efectos de los fármacos , Infecciones por VIH/tratamiento farmacológico , Adolescente , Recuento de Linfocito CD4 , Niño , Preescolar , Farmacorresistencia Viral/genética , Quimioterapia Combinada , Femenino , Infecciones por VIH/mortalidad , Infecciones por VIH/virología , VIH-1/efectos de los fármacos , Humanos , Lactante , Estimación de Kaplan-Meier , Masculino , Mutación , Inhibidores de la Transcriptasa Inversa/uso terapéutico , Carga Viral/efectos de los fármacos
4.
PLoS Genet ; 8(8): e1002875, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22912594

RESUMEN

A key challenge in the production of second generation biofuels is the conversion of lignocellulosic substrates into fermentable sugars. Enzymes, particularly those from fungi, are a central part of this process, and many have been isolated and characterised. However, relatively little is known of how fungi respond to lignocellulose and produce the enzymes necessary for dis-assembly of plant biomass. We studied the physiological response of the fungus Aspergillus niger when exposed to wheat straw as a model lignocellulosic substrate. Using RNA sequencing we showed that, 24 hours after exposure to straw, gene expression of known and presumptive plant cell wall-degrading enzymes represents a huge investment for the cells (about 20% of the total mRNA). Our results also uncovered new esterases and surface interacting proteins that might form part of the fungal arsenal of enzymes for the degradation of plant biomass. Using transcription factor deletion mutants (xlnR and creA) to study the response to both lignocellulosic substrates and low carbon source concentrations, we showed that a subset of genes coding for degradative enzymes is induced by starvation. Our data support a model whereby this subset of enzymes plays a scouting role under starvation conditions, testing for available complex polysaccharides and liberating inducing sugars, that triggers the subsequent induction of the majority of hydrolases. We also showed that antisense transcripts are abundant and that their expression can be regulated by growth conditions.


Asunto(s)
Aspergillus niger/genética , Proteínas Fúngicas/genética , Regulación Fúngica de la Expresión Génica , Lignina/metabolismo , ARN Mensajero/biosíntesis , Activación Transcripcional , Aspergillus niger/enzimología , Biomasa , Esterasas/biosíntesis , Esterasas/genética , Proteínas Fúngicas/biosíntesis , Perfilación de la Expresión Génica , Glicósido Hidrolasas/biosíntesis , Glicósido Hidrolasas/genética , Monosacáridos/biosíntesis , Proteínas Represoras/deficiencia , Proteínas Represoras/genética , Análisis de Secuencia de ARN , Transactivadores/deficiencia , Transactivadores/genética , Triticum/metabolismo
5.
ACS Omega ; 9(29): 32097-32106, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39072092

RESUMEN

Pentaerythritol tetranitrate (PETN) has been used extensively in commercial detonators and other explosive applications for many decades. Here, we show the results of a comprehensive 1.5 year aging study of PETN in commercial detonators, addressing batch-to-batch variations, surface area changes, and comparisons of aged loose powders side-by-side with identically aged detonators. Function time analysis of the aged detonators has also been provided and discussed in the context of powder aging. This large-scale, statistically relevant study addresses long-standing questions on PETN aging without the complications from making comparisons between multiple batches of material. We have evaluated the aging time required to reach the maximum measured amount of PETN coarsening and estimated an activation barrier of ∼123 kJ mol-1, which is higher than literature values reported by Gee et al. It is possible that this discrepancy is due to the fact that that this study cannot quantify the relative contributions of surface diffusion versus sublimation processes. At the lower temperatures of 50 and 60 °C, we assume that surface diffusion dominates over sublimation processes, even at longer aging times. At the higher temperature of 75 °C, we assume that both surface diffusion and sublimation contribute at the early time points, which are included in the Arrhenius analysis for coarsening.

6.
Rev Sci Instrum ; 95(7)2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-39037303

RESUMEN

There are few techniques available for chemists to obtain time-to-explosion data with known temperature inputs at the early stages of the design and synthesis of new explosives. In the 1960s, a technique was developed to rapidly heat milligram-quantities of confined explosives to ∼1000 K on microsecond timescales. Wenograd [Trans. Faraday Soc. 57, 1612 (1961)] loaded explosives inside stainless steel hypodermic needles, connected them to a fireset and rapidly discharged a capacitor through the steel. He obtained the temperature by measuring the needle resistance in a Wheatstone bridge arrangement and the time to explosion from a needle rupture. However, owing to the narrow-gauge needles used in the original research, the experiment was only possible with melt-castable explosives; it was never replicated, and modern diagnostics are now available with advances beyond the 1960s. Here, we report the development of the High Explosives Initiation Time (HEIT) test, which utilizes a 250 J pulsed power system to heat the needles. This work extends the Wenograd approach by using optical diagnostics, computational modeling, and advanced techniques to measure needle resistance and needle rupture. Preliminary rate information for pentaerythritol tetranitrate (PETN) will be presented.

7.
Rapid Commun Mass Spectrom ; 25(13): 1794-800, 2011 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-21638354

RESUMEN

Preserved and archived organic material offers huge potential for the conduct of retrospective and long-term historical ecosystem reconstructions using stable isotope analyses, but because of isotopic exchange with preservatives the obtained values require validation. The Continuous Plankton Recorder (CPR) Survey is the most extensive long-term monitoring program for plankton communities worldwide and has utilised ships of opportunity to collect samples since 1931. To keep the samples intact for subsequent analysis, they are collected and preserved in formalin; however, previous studies have found that this may alter stable carbon and nitrogen isotope ratios in zooplankton. A maximum ~0.9‰ increase of δ(15) N and a time dependent maximum ~1.0‰ decrease of δ(13) C were observed when the copepod, Calanus helgolandicus, was experimentally exposed to two formalin preservatives for 12 months. Applying specific correction factors to δ(15) N and δ(13) C values for similarly preserved Calanoid species collected by the CPR Survey within 12 months of analysis may be appropriate to enable their use in stable isotope studies. The isotope values of samples stored frozen did not differ significantly from those of controls. Although the impact of formalin preservation was relatively small in this and other studies of marine zooplankton, changes in isotope signatures are not consistent across taxa, especially for δ(15) N, indicating that species-specific studies may be required.


Asunto(s)
Isótopos de Carbono/análisis , Copépodos/química , Monitoreo del Ambiente/normas , Formaldehído/química , Isótopos de Nitrógeno/análisis , Conservación de Tejido/métodos , Animales , Copépodos/metabolismo , Criopreservación , Recolección de Datos/normas , Plancton , Reproducibilidad de los Resultados , Factores de Tiempo , Conservación de Tejido/normas
8.
Methods Mol Biol ; 2133: 327-341, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32144675

RESUMEN

Cyclotides are naturally occurring microproteins (≈30 residues long) present in several families of plants. All cyclotides share a unique head-to-tail circular knotted topology containing three disulfide bridges forming a cystine knot topology. Cyclotides possess high stability to chemical, physical, and biological degradation and have been reported to cross cellular membranes. In addition, naturally occurring and engineered cyclotides have shown to possess various pharmacologically relevant activities. These unique features make the cyclotide scaffold an excellent tool for the design of novel peptide-based therapeutics by using molecular evolution and/or peptide epitope grafting techniques. In this chapter, we provide protocols to recombinantly produce a natively folded cyclotide making use of a standard bacterial expression system in combination with an intein-mediated backbone cyclization with concomitant oxidative folding.


Asunto(s)
Clonación Molecular/métodos , Ciclotidas/biosíntesis , Ingeniería de Proteínas/métodos , Proteínas Recombinantes de Fusión/biosíntesis , Cromatografía de Afinidad/métodos , Cromatografía en Agarosa/métodos , Cromatografía Líquida de Alta Presión , Ciclización , Ciclotidas/química , Ciclotidas/genética , Ciclotidas/aislamiento & purificación , Cistina/química , Motivos Nodales de Cisteina , Disulfuros/química , Disulfuros/metabolismo , Electroforesis en Gel de Poliacrilamida , Escherichia coli/genética , Inteínas , Proteínas de Plantas/biosíntesis , Proteínas de Plantas/química , Proteínas de Plantas/aislamiento & purificación , Pliegue de Proteína , Procesamiento Proteico-Postraduccional , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/aislamiento & purificación
9.
Contemp Clin Trials ; 91: 105956, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32061969

RESUMEN

BACKGROUND: Community-based programs have had modest success in combating obesity in Latino populations. Latino families' norms and beliefs about weight often hold larger body sizes to be normal, leading to lower engagement in weight-focused programs. Because improvements in cardiorespiratory fitness confer health benefits, regardless of weight, they offer an alternative to obesity-focused approaches. We describe the rationale and design of Athletes for Life (AFL), a community- and family-based intervention for Latino families. METHODS/DESIGN: This two-group randomized controlled trial will test the efficacy of AFL for improving cardiorespiratory fitness and diet in 6- to 11-year-old children (N = 160) and their parents, relative to a wait-list control group. Children will participate in 12 weeks of semiweekly sports skill programing and nutrition sessions. Concurrently, parents will participate in sports-focused activity and behavior change sessions that focus on nutrition, chronic disease prevention, and healthy eating. Cardiovascular fitness will be measured by the 1-mile run and 3-min step-test for both parents and children. Secondary outcomes include changes in objectively measured physical activity, dietary measures, body composition, and cardiometabolic risk (waist circumference, blood pressure, blood lipids, glucose, insulin, and C-reactive protein). DISCUSSION: AFL, implemented with a strong community partnership, will provide a test of the efficacy of culturally tailored intervention programming to promote positive health behaviors and improve health outcomes in Latino families. Intervention content, structure, and messaging will provide guidance for future methods to engage Latino families in health promotion programs that highlight their cultural norms, and beliefs. TRIAL REGISTRATION: Clinicaltrials.gov Identifier NCT03761589 (12/3/2018).


Asunto(s)
Ejercicio Físico , Salud de la Familia/etnología , Promoción de la Salud/organización & administración , Hispánicos o Latinos , Deportes , Niño , Femenino , Humanos , Masculino , Proyectos de Investigación
11.
Biomedicines ; 7(2)2019 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-31010257

RESUMEN

Cyclotides are a novel class of micro-proteins (≈30-40 residues long) with a unique topology containing a head-to-tail cyclized backbone structure further stabilized by three disulfide bonds that form a cystine knot. This unique molecular framework makes them exceptionally stable to physical, chemical, and biological degradation compared to linear peptides of similar size. The cyclotides are also highly tolerant to sequence variability, aside from the conserved residues forming the cystine knot, and are orally bioavailable and able to cross cellular membranes to modulate intracellular protein-protein interactions (PPIs), both in vitro and in vivo. These unique properties make them ideal scaffolds for many biotechnological applications, including drug discovery. This review provides an overview of the properties of cyclotides and their potential for the development of novel peptide-based therapeutics. The selective disruption of PPIs still remains a very challenging task, as the interacting surfaces are relatively large and flat. The use of the cell-permeable highly constrained polypeptide molecular frameworks, such as the cyclotide scaffold, has shown great promise, as it provides unique pharmacological properties. The use of molecular techniques, such as epitope grafting, and molecular evolution have shown to be highly effective for the selection of bioactive cyclotides. However, despite successes in employing cyclotides to target PPIs, some of the challenges to move them into the clinic still remain.

12.
Hosp Pediatr ; 9(5): 365-372, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30952690

RESUMEN

BACKGROUND AND OBJECTIVES: Self-harm among adolescents is a common problem, resulting in large numbers of patients admitted for medical stabilization after a suicide attempt. Because of limited mental health resources, these high-risk patients remain in inpatient settings once medically stabilized until psychiatric placement can be arranged. During this time, patients are at risk for safety events, including self-harm and elopement. Using quality improvement (QI) methodology, we aimed to reduce the frequency of significant safety events (SSEs) in this population by targeting modifiable risk factors and standardizing care. METHODS: This was a QI study conducted at a medium-sized academic center. Key interventions included the development of the Pediatric Behavioral Health Safety Protocol, standardization of the patient safety search, and implementation of a daily Safety Huddle. Process measures were selected as metrics of use and adherence to the newly developed protocol. The rate of SSEs per 100 patient days was the primary outcome measure. RESULTS: There were 224 patients included in our study: 53 in the preimplementation and 171 in the postimplementation groups. Use of the Pediatric Behavioral Health Safety Protocol increased to 91.8% after implementation. The rate of SSEs per 100 patient days decreased from an average of 2.7 events per 100 patient days in the preimplementation period to 0.17 events per 100 patient days in the postimplementation period. CONCLUSIONS: The use of QI methodology to improve safety for adolescents admitted after a suicide attempt led to a substantial and sustainable reduction in the rate of SSEs at our institution.


Asunto(s)
Hospitalización/estadística & datos numéricos , Seguridad del Paciente/normas , Mejoramiento de la Calidad/normas , Conducta Autodestructiva/prevención & control , Intento de Suicidio , Adolescente , Femenino , Encuestas de Atención de la Salud , Humanos , Masculino , Factores de Riesgo , Administración de la Seguridad/normas , Conducta Autodestructiva/psicología , Intento de Suicidio/psicología
13.
Artículo en Inglés | MEDLINE | ID: mdl-28165418

RESUMEN

Background: Conflicting interests, power imbalance and relationships characterized by distrust are just a few of the many challenges community-academic research partnerships face. In addition, the time it takes to build relationships is often overlooked, which further complicates matters and can leave well-intentioned individuals re-creating oppressive conditions through inauthentic partnerships. This paper presents a novel approach of using meeting minutes to explore partnership dynamics. The Community Assessment of Freeway Exposure and Health (CAFEH) partnership is used as an illustrative case study to identify how community academic partnerships overcome the challenges associated with community-based participatory research (CBPR). CAFEH is a study of ultrafine particle exposure (UFP) near highways in the Boston, MA area. Methods: Qualitative analysis was applied to meeting minutes and process evaluation reports from the first three years of the CAFEH study (n = 73 files). In addition, a group meeting was held with project partners in order to contextualize the findings from the document analysis. Results: The three most commonly referenced challenges included language barriers, the overall project structure and budgetary constraints. Meanwhile, a heavy emphasis on process and an approach steeped in participatory democracy facilitated CAFEH's ability to overcome these challenges, as well as sustain and augment strong partnership ties. Conclusions: This experience suggests that leadership that incorporates an organizing approach and a transformational style facilitates CBPR processes and helps teams surmount challenges.


Asunto(s)
Investigación Participativa Basada en la Comunidad/organización & administración , Relaciones Comunidad-Institución , Democracia , Material Particulado/análisis , Características de la Residencia/estadística & datos numéricos , Boston , Presupuestos , Barreras de Comunicación , Humanos , Lenguaje , Racismo
14.
Artículo en Español | LILACS | ID: lil-91997

RESUMEN

Se presenta un plan de atención de cuidados de enfermería elaborado en base a las complicaciones más frecuentes que se pueden presentar en el período post-operatorio de la cirugía de columna, especificamente de la escoliosis y se emplean los diagnósticos y estándares de enfermería según los problemas, reales o potenciales, del paciente. Los problemas se clasifican en pulmonares, hemodinámicos, neurológicos, urinarios, gastrointestinales, alergícos, e infecciosos


Asunto(s)
Escoliosis/cirugía , Enfermería Primaria , Complicaciones Posoperatorias
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