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1.
Int J Biol Macromol ; 268(Pt 1): 131689, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38642680

RESUMEN

Plastic pollution is primarily caused by the accumulation of petroleum-derived plastics, as they tend to degrade slowly. Sustainable alternatives to these materials are bio-based and biodegradable plastics, such as polylactic acid (PLA). In this study, we assessed how turning aeration and the initial carbon/nitrogen (C/N) ratio impact PLA biodegradation. The study was carried out under controlled composting conditions, over 180 days, with the aim of decreasing the biodegradation time of the PLA. Apple pomace, rice husk, grape pomace compost, and PLA were used as substrates in the composting process. The experiments were conducted using three types of turning aeration: without turning, one turn per week, and two turns per week. Three initial C/N ratios were used: 20, 30, and 40. A stepwise temperature ramp was designed and implemented to simulate industrial composting conditions, which influence microbial activity and thus the rate of decomposition of substrates, including PLA. The data showed behavior; hence, a nonlinear regression model based on the logistic growth equation was used to predict the PLA biodegradation at the end of the composting process. The results showed that two turns per week with an initial C/N ratio of 30 or 40 led to a 90 % biodegradation of the PLA in 130 days. This degradation was verified by Fourier-Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM).


Asunto(s)
Biodegradación Ambiental , Carbono , Nitrógeno , Poliésteres , Nitrógeno/química , Nitrógeno/metabolismo , Poliésteres/química , Poliésteres/metabolismo , Carbono/química , Carbono/metabolismo , Compostaje/métodos , Temperatura
2.
Endocr Pract ; 30(2): 122-127, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37952581

RESUMEN

OBJECTIVE: People with diabetes mellitus, particularly those with limited access to longitudinal care, frequently present to the emergency department (ED). Continuous glucose monitoring (CGM) has been shown to improve outcomes in ambulatory settings, so we hypothesized that it would be beneficial if initiated upon ED discharge. METHODS: We randomized adults with diabetes who were seen in the ED for hypo- or hyperglycemia to either 14 days of flash CGM or care coordination alone. All participants were scheduled to follow up in our diabetes specialty clinic. Outcomes included clinic attendance, the 3-month change in hemoglobin A1c, and repeat ED utilization. RESULTS: We recruited 30 participants, including 13 with newly diagnosed diabetes. All but one (97%) had type 2 diabetes. We found no significant difference between the CGM (n = 16) and control (n = 14) groups in terms of clinic attendance (75 vs 64%, P = .61) or repeat ED utilization (31 vs 50%, P = .35), although our power was low. The absolute reduction in A1c was greater in the CGM group (5.2 vs 2.4%, P = .08). Among newly diagnosed participants for whom we had data, 7 out of 7 in the CGM group had a follow-up A1c under 7% compared to 1 out of 3 in the control group (P = .03). Over 90% of patients and providers found the CGM useful. CONCLUSIONS: Our data demonstrate the feasibility of starting CGM in the ED, a valuable setting for engaging difficult-to-reach patients. Our pilot study was limited by its small sample size, however, as recruitment in the ED can be challenging.


Asunto(s)
Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Hipoglucemia , Adulto , Humanos , Glucemia , Hemoglobina Glucada , Hipoglucemiantes , Hipoglucemia/diagnóstico , Proyectos Piloto , Diabetes Mellitus Tipo 2/terapia , Automonitorización de la Glucosa Sanguínea , Monitoreo Continuo de Glucosa , Alta del Paciente
3.
Cad. Bras. Ter. Ocup ; 31: e3506, 2023. graf
Artículo en Español | LILACS-Express | LILACS, Index Psicología - Revistas | ID: biblio-1528178

RESUMEN

Resumen Objetivo Conocer las investigaciones dentro de la Ciencia Ocupacional que involucran a la población LGBT. Metodología Se realizó una revisión de literatura utilizando las siguientes bases de datos PubMed, Web of Science, SCOPUS y EBSCOhost y una consulta directa en el listado de referencias. Resultados Se seleccionaron 24 artículos para ser analizados y se agruparon en 3 categorías generales según el tipo de grupo perteneciente a la población LGBT que se estudió. Las categorías que fueron (1) personas trans y ocupación, (2) hombres gays y ocupación y (3) mujeres lesbianas y ocupación. Estas categorías a su vez fueron divididas en ejes temáticas específicos. Conclusion Los estudios desde la ciencia ocupacional han abarcado de forma acotada las experiencias ocupacionales de las personas LGBT. La transición ocupacional y la performatividad del género a través de la ocupación son temas que se abordan de manera transversal en la mayoría de las categorías de análisis. Se destaca una falta de enfoque interseccional en las investigaciones emergentes para poder comprender de manera más compleja la ocupación y las estructuras de exclusión y discriminación que viven las personas LGBT.


Resumo Objetivo Conhecer as investigações dentro da Ciência Ocupacional que envolvem a população LGBT. Metodologia Foi realizada uma revisão de literatura utilizando as seguintes bases de dados: PubMed, Web of Science, SCOPUS e EBSCOhost, e uma consulta direta na lista de referências. Resultados 24 artigos foram selecionados para serem analisados e agrupados em 3 categorias gerais de acordo com o tipo de grupo pertencente à população LGBT estudada. As categorias foram (1) pessoas trans e ocupação, (2) homens gays e ocupação e (3) mulheres lésbicas e ocupação. Essas categorias, por sua vez, foram divididas em eixos temáticos específicos. Conclusão Os estudos da ciência ocupacional têm abordado de forma limitada as experiências ocupacionais de pessoas LGBT. A transição ocupacional e a performatividade de gênero através da ocupação são questões abordadas de forma transversal na generalidade das categorias de análise. A falta de abordagem interseccional é destacada em pesquisas emergentes para poder compreender de forma mais complexa a ocupação e as estruturas de exclusão e discriminação vivenciadas por pessoas LGBT.


Abstract Objective To know the investigations within occupational science that involve the LGBT population. Methodology A literature review was performed using the following databases: PubMed, Web of Science, SCOPUS, and EBSCOhost, and a direct query in the list of references. Results 24 articles were selected to be analyzed and grouped into 3 general categories according to the type of group belonging to the LGBT population that was studied. The categories were (1) trans people and occupation, (2) gay men and occupation, and (3) lesbian women and occupation. These categories, in turn, were divided into specific thematic axes. Conclusion Occupational science studies have covered the occupational experiences of LGBT people in a limited way. Occupational transition and gender performativity through occupation are issues that are addressed transversally in most categories of analysis. A lack of intersectional approach is highlighted in emerging research to be able to understand in a more complex way the occupation and the structures of exclusion and discrimination experienced by LGBT people.

4.
J Clin Invest ; 132(21)2022 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-36317634

RESUMEN

BackgroundNeuroendocrine prostate cancer (NEPC) is an aggressive subtype, the presence of which changes the prognosis and management of metastatic prostate cancer.MethodsWe performed analytical validation of a Circulating Tumor Cell (CTC) multiplex RNA qPCR assay to identify the limit of quantification (LOQ) in cell lines, synthetic cDNA, and patient samples. We next profiled 116 longitudinal samples from a prospectively collected institutional cohort of 17 patients with metastatic prostate cancer (7 NEPC, 10 adenocarcinoma) as well as 265 samples from 139 patients enrolled in 3 adenocarcinoma phase II trials of androgen receptor signaling inhibitors (ARSIs). We assessed a NEPC liquid biomarker via the presence of neuroendocrine markers and the absence of androgen receptor (AR) target genes.ResultsUsing the analytical validation LOQ, liquid biomarker NEPC detection in the longitudinal cohort had a per-sample sensitivity of 51.35% and a specificity of 91.14%. However, when we incorporated the serial information from multiple liquid biopsies per patient, a unique aspect of this study, the per-patient predictions were 100% accurate, with a receiver-operating-curve (ROC) AUC of 1. In the adenocarcinoma ARSI trials, the presence of neuroendocrine markers, even while AR target gene expression was retained, was a strong negative prognostic factor.ConclusionOur analytically validated CTC biomarker can detect NEPC with high diagnostic accuracy when leveraging serial samples that are only feasible using liquid biopsies. Patients with expression of NE genes while retaining AR-target gene expression may indicate the transition to neuroendocrine differentiation, with clinical characteristics consistent with this phenotype.FundingNIH (DP2 OD030734, 1UH2CA260389, R01CA247479, and P30 CA014520), Department of Defense (PC190039 and PC200334), and Prostate Cancer Foundation (Movember Foundation - PCF Challenge Award).


Asunto(s)
Adenocarcinoma , Neoplasias de la Próstata , Humanos , Masculino , Receptores Androgénicos/genética , Receptores Androgénicos/metabolismo , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/metabolismo , Adenocarcinoma/diagnóstico , Adenocarcinoma/genética , Adenocarcinoma/patología , Biomarcadores , Transducción de Señal , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica
5.
Rev. med. Chile ; 150(10): 1334-1341, oct. 2022. ilus, tab
Artículo en Español | LILACS | ID: biblio-1431849

RESUMEN

BACKGROUND: The use of glucose lowering agents with favorable weight profile is a growing practice in Diabetology. AIM: To characterize medication combinations in patients with type 2 Diabetes (T2D) and their effect on metabolic control. MATERIAL AND METHODS: Review of medical records of 249 outpatients with T2D with a median age of 66 years, cared for at a medical network. Clinical characteristics, glycated hemoglobin (HbA1c), details of Diabetes treatment (types of drugs or insulin), renal function, lipids and B12 vitamin levels were registered. RESULTS: The median disease duration was 16 years. The most recent HbA1c was 7.4%. No patient was using sulfonylureas, 45 were using Dipeptidyl peptidase 4 inhibitors, 113 were using Sodium-glucose Cotransporter-2 (SGLT2i) Inhibitors, 21 used Glucagon-like Peptide-1 Receptor Agonists (GLP1ra), 158 used basal insulin and 61 on basal plus bolus insulin. The use of SGLT2i or GLP1ra was associated with a metabolic control similar to those patients not using them, while patients on rapid insulin had a significantly worse metabolic control and a tendency to greater body mass index. The use of basal insulin and rapid insulin was significantly associated with more hypoglycemia events. CONCLUSIONS: The use of SGLT2i and GLP1ra in patients with T2D is associated with better metabolic control than rapid insulin with less risk of hypoglycemia. The use of these therapies should be prioritized in the future.


Asunto(s)
Humanos , Masculino , Femenino , Persona de Mediana Edad , Anciano , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Atención Ambulatoria , Hipoglucemiantes/efectos adversos , Hipoglucemiantes/uso terapéutico , Hemoglobina Glucada/metabolismo , Combinación de Medicamentos , Hipoglucemia/inducido químicamente , Insulina/efectos adversos
6.
Biomark Res ; 10(1): 26, 2022 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-35468853

RESUMEN

INTRODUCTION: PD-L1 expression in non-small cell lung cancer (NSCLC) predicts response to immune checkpoint blockade, however is an imperfect biomarker given tumor heterogeneity, and the antigen presentation pathway requiring other components including HLA I expression. HLA I downregulation may contribute to resistance, warranting its evaluation in attempts to guide patient selection. In addition, earlier detection of acquired resistance could prompt earlier change in treatment and prolong patient survival. Analysis of circulating tumor cells (CTCs) captures heterogeneity across multiple sites of metastases, enables detection of changes in tumor burden that precede radiographic response, and can be obtained in serial fashion. METHODS: To quantify the expression of both PD-L1 and HLA I on CTCs, we developed exclusion-based sample preparation technology, achieving high-yield with gentle magnetic movement of antibody-labeled cells through virtual barriers of surface tension. To achieve clinical-grade quantification of rare cells, we employ high quality fluorescence microscopy image acquisition and automated image analysis together termed quantitative microscopy. RESULTS: In preparation for clinical laboratory implementation, we demonstrate high precision and accuracy of these methodologies using a diverse set of control materials. Preliminary testing of CTCs isolated from patients with NSCLC demonstrate heterogeneity in PD-L1 and HLA I expression and promising clinical value in predicting PFS in response to PD-L1 targeted therapies. CONCLUSIONS: By confirming high performance, we ensure compatibility for clinical laboratory implementation and future application to better predict and detect resistance to PD-L1 targeted therapy in patients with NSCLC.

7.
Rev Med Chil ; 150(10): 1334-1341, 2022 Oct.
Artículo en Español | MEDLINE | ID: mdl-37358092

RESUMEN

BACKGROUND: The use of glucose lowering agents with favorable weight profile is a growing practice in Diabetology. AIM: To characterize medication combinations in patients with type 2 Diabetes (T2D) and their effect on metabolic control. MATERIAL AND METHODS: Review of medical records of 249 outpatients with T2D with a median age of 66 years, cared for at a medical network. Clinical characteristics, glycated hemoglobin (HbA1c), details of Diabetes treatment (types of drugs or insulin), renal function, lipids and B12 vitamin levels were registered. RESULTS: The median disease duration was 16 years. The most recent HbA1c was 7.4%. No patient was using sulfonylureas, 45 were using Dipeptidyl peptidase 4 inhibitors, 113 were using Sodium-glucose Cotransporter-2 (SGLT2i) Inhibitors, 21 used Glucagon-like Peptide-1 Receptor Agonists (GLP1ra), 158 used basal insulin and 61 on basal plus bolus insulin. The use of SGLT2i or GLP1ra was associated with a metabolic control similar to those patients not using them, while patients on rapid insulin had a significantly worse metabolic control and a tendency to greater body mass index. The use of basal insulin and rapid insulin was significantly associated with more hypoglycemia events. CONCLUSIONS: The use of SGLT2i and GLP1ra in patients with T2D is associated with better metabolic control than rapid insulin with less risk of hypoglycemia. The use of these therapies should be prioritized in the future.


Asunto(s)
Atención Ambulatoria , Diabetes Mellitus Tipo 2 , Hipoglucemiantes , Anciano , Humanos , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hemoglobina Glucada/metabolismo , Hipoglucemia/inducido químicamente , Hipoglucemiantes/efectos adversos , Hipoglucemiantes/uso terapéutico , Insulina/efectos adversos , Combinación de Medicamentos , Persona de Mediana Edad , Masculino , Femenino
8.
Trials ; 22(1): 754, 2021 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-34717750

RESUMEN

BACKGROUND: During child psychiatry hospitalization, working with the families or attachment figures is a challenge, most of the children who are admitted to these units come from multi-problem families, with limited research in this area. Video feedback (VF) interventions have proved to be a powerful resource to promote parental and child well-being in small children and has been used with parents with a psychiatric condition. Parental Reflective Functioning (PRF) is one of the parental abilities that can be improved with VF and could be especially important in coping with conflict and negative emotions in older children. The aim of this study is to implement Video Intervention Therapy (VIT) to enhance PRF in primary caregivers of inpatient psychiatric children. As there is no published research using VF with parents of children with severe psychopathology in a hospitalized context. This report, then, becomes a much needed pilot study providing evidence for a larger randomized control trial (RCT). METHODS: The study is a single-center, two-arm feasibility randomized control trial with a qualitative component. Block randomization was done to generate a 2:1 allocation, leaving more participants in the intervention group. The intervention comprises four modules; every module has both one video-recorded play session and one VIT session (in a group setting) per week. Evaluation of the caregivers included assessments of PRF and well-being, and child assessment included parent-ratings and clinician-ratings of symptomatology and general functioning. RESULTS: Thirty participants were randomized; eligibility and recruitment rate were 70.6% and 83.3%, respectively. The compliance-to-intervention rate was 85% in the VIT group and 90% in the control group. All participants completed entry evaluation and 90% at the 3-month follow-up. The intervention was acceptable to participants and feasible for therapists to deliver. Outcome data must be treated with caution due to the small numbers involved, yet indicate that the VIT may have a positive effect in improving parental and child mental health outcomes. CONCLUSIONS: VIT for primary caregivers of child inpatient children was feasible to deliver and acceptable for participants, therapist, and the staff unit involved; there is sufficient evidence to undertake a full-scale effectiveness RCT. TRIAL REGISTRATION: ClinicalTrials.gov NCT03374904 . Registered on 14 December 2017.


Asunto(s)
Psiquiatría Infantil , Trastornos Mentales , Cuidadores , Niño , Estudios de Factibilidad , Humanos , Padres
9.
Investig. enferm ; 23(1)2021. 2 tab; 1 graf
Artículo en Español | LILACS, BDENF - Enfermería, COLNAL | ID: biblio-1373225

RESUMEN

Objetivo: identificar la evidencia disponible de las características del síndrome post unidad de cuidado intensivo en el paciente que egresa de la unidad de cuidado intensivo. Método: revisión de alcance con la metodología del Joanna Briggs Institut, en cinco bases de datos con la estrategia de búsqueda ([PostIntensive AND Care AND Syndrome] [Nursing AND Care AND PICS]). Se incluyeron estudios primarios publicados entre los años 2010 y 2020, disponibles en texto completo. Resultados: después del análisis de los 48 estudios primarios se extrajeron seis categorías temáticas así: aspecto cognitivo en el síndrome post UCI, osteomusculares, psicoemocionales, estrategias de prevención con modelos de sobrevivientes de UCI, síndrome post unidad cuidado intensivo en la familia y herramientas de evaluación. Conclusiones: mejorar la calidad de atención de los pacientes que presentan este síndrome, prevenir la aparición y aumentar la calidad de vida prestada a los sobrevivientes de UCI y sus familias. La evidencia reporta que entre los cuidadores se pueden desencadenar distintos trastornos que disminuyen su calidad de vida. La enfermería juega un papel crucial en la prevención de la aparición del síndrome mediante estrategias en la UCI e interdisciplinares; los planes de egreso y seguimiento a los pacientes pueden lograr que estos se rehabiliten más rápido y eviten discapacidades o secuelas a largo plazo.


Objective: to identify the available evidence regarding the post ICU syndrome in patients leaving the intensive care unit. Methods: it is a review of scope according to the Joanna Briggs Institut methodology, in 5 data bases with the search strategy ([PostIntensive AND Care AND Syndrome] [Nursing AND Care AND PICS]). Primary studies published between 2010 and 2020 with full text available were included. Results: having analyzed 48 primary studies, 6 thematic categories were created: cognitive aspect in post ICU syndrome, musculoskeletal, psycho-emotional, prevention strategies with models of ICU survivors, post ICU syndrome in the family and evaluation tools. Conclusions: To improve the health care in patient in post ICU syndrome, to prevent the syndrome emergence and increase the quality of life provided to the ICU survivors and their families. Evidence shows that caregivers can develop different disorders that impact their quality of life. Nursing plays a crucial role in preventing the syndrome advent by using interdisciplinary and ICU strategies. This charge and follow-up plans can make these patients to achieve a faster rehabilitation and avoid impairment or sequels in the future


Objetivo: identifcar a evidência disponível das características da síndrome pós-unidade de terapia intensiva em pacientes egressos da unidade de terapia intensiva. Método: revisão do escopo com a metodologia do Joanna Briggs Institut, em cinco bases de dados com a estratégia de busca ([PostIntensive AND Care AND Syndrome] [Nursing AND Care AND PICS]). Incluíram-se estudos primários publicados entre 2010 e 2020, disponíveis em texto completo. Resultados: após análise dos 48 estudos primários foram extraídas seis categorias temáticas: aspecto cognitivo na síndrome pós-UTI, osteomuscular, psicoemocional, estratégias de prevenção com modelos de sobrevivência na UTI, síndrome pós-unidade de Terapia intensiva na família e ferramentas de avaliação. Conclusões: melhorar a qualidade da atenção dos pacientes que apresentam a síndrome, prevenir a aparição e aumentar a qualidade de vida prestada aos sobreviventes da UTI e suas famílias. Evidências relatam que diversos transtornos podem se desencadear entre os cuidadores que reduzem sua qualidade de vida. A enfermagem tem um papel crucial na prevenção da aparição da síndrome mediante estratégias na UTI e interdisciplinares; planos de alta e acompanhamento aos pacientes podem conseguir uma reabilitação mais rápida e evitar incapacidades ou sequelas no longo praz


Asunto(s)
Humanos , Unidades de Cuidados Intensivos , Cuidadores , Cuidados Posteriores , Cuidados Críticos
10.
J Clin Hypertens (Greenwich) ; 22(6): 1041-1049, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32497408

RESUMEN

Several lifestyle and sociodemographic factors are associated with blood pressure (BP). The authors conducted a retrospective study of 4870 subjects from the National Health Survey 2009 in Chile to identify exposure factors associated with increasing BP levels. Subjects with isolated urinary excretion of sodium (n = 2873), potassium, and creatinine were included to estimate daily salt intake and urinary sodium/potassium (Na/K) ratio. Hypertension was defined according to European guidelines 2018 and American guidelines ACC/AHA 2017. Proportional odds models were developed to analyze education level, sedentarism, smoking, alcohol intake, estimated urinary Na/K ratio, estimated daily salt intake, and body mass index (BMI) as factors associated with increasing BP levels (from high-normal BP to hypertension). Logistic regression models were checked for overdispersion. Mean age and BMI of the population were 42 years old and 27 kg/m2 , respectively; 19% had low education level and 27% had hypertension according to European guidelines, whereas 47% according to ACC/AHA criteria. Mean estimated urinary Na/K ratio was 4 ± 2, and mean salt consumption was 10 ± 2 g/day. Estimated urinary Na/K ratio (OR, 1.11; 95% CI, 1.01-1.21), BMI (OR, 1.10; 95% CI, 1.07-1.13), estimated daily salt intake (OR, 1.10; 95% CI, 1.03-1.17), and alcohol intake (OR, 1.03; 95% CI, 1.01-1.05) were significantly associated with hypertension. This study highlights that a healthy diet and weight control should be important components of BP management plans, and it suggests that public policies should include close monitoring of these factors to reduce hypertension prevalence and improve its management in a Latino population.


Asunto(s)
Hipertensión , Potasio , Sodio , Adulto , Presión Sanguínea , Índice de Masa Corporal , Chile/epidemiología , Estudios Transversales , Encuestas Epidemiológicas , Humanos , Hipertensión/epidemiología , Hipertensión/orina , Potasio/orina , Estudios Retrospectivos , Sodio/orina
11.
Int J Comput Assist Radiol Surg ; 14(11): 1945-1953, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31502194

RESUMEN

PURPOSE: (1) To improve the accuracy of global and regional alveolar-recruitment quantification in CT scan pairs by accounting for lung-tissue displacements and deformation, (2) To propose a method for local-recruitment calculation. METHODS: Recruitment was calculated by subtracting the quantity of non-aerated lung tissues between expiration and inspiration. To assess global recruitment, lung boundaries were first interactively delineated at inspiration, and then they were warped based on automatic image registration to define the boundaries at expiration. To calculate regional recruitment, the lung mask defined at inspiration was cut into pieces, and these were also warped to encompass the same tissues at expiration. Local-recruitment map was calculated as follows: For each voxel at expiration, the matching location at inspiration was determined by image registration, non-aerated voxels were counted in the neighborhood of the respective locations, and the voxel count difference was normalized by the neighborhood size. The methods were evaluated on 120 image pairs of 12 pigs with experimental acute respiratory distress syndrome. RESULTS: The dispersion of global- and regional-recruitment values decreased when using image registration, compared to the conventional approach neglecting tissue motion. Local-recruitment maps overlaid onto the original images were visually consistent, and the sum of these values over the whole lungs was very close to the global-recruitment estimate, except four outliers. CONCLUSIONS: Image registration can compensate lung-tissue displacements and deformation, thus improving the quantification of alveolar recruitment. Local-recruitment calculation can also benefit from image registration, and its values can be overlaid onto the original image to display a local-recruitment map. They also can be integrated over arbitrarily shaped regions to assess regional or global recruitment.


Asunto(s)
Pulmón/diagnóstico por imagen , Síndrome de Dificultad Respiratoria/diagnóstico , Tomografía Computarizada por Rayos X/métodos , Animales , Modelos Animales de Enfermedad , Porcinos
12.
Nat Commun ; 9(1): 164, 2018 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-29323112

RESUMEN

Sensing and uptake of external ammonium is essential for anaerobic ammonium-oxidizing (anammox) bacteria, and is typically the domain of the ubiquitous Amt/Rh ammonium transporters. Here, we report on the structure and function of an ammonium sensor/transducer from the anammox bacterium "Candidatus Kuenenia stuttgartiensis" that combines a membrane-integral ammonium transporter domain with a fused histidine kinase. It contains a high-affinity ammonium binding site not present in assimilatory Amt proteins. The levels of phosphorylated histidine in the kinase are coupled to the presence of ammonium, as conformational changes during signal recognition by the Amt module are transduced internally to modulate the kinase activity. The structural analysis of this ammonium sensor by X-ray crystallography and small-angle X-ray-scattering reveals a flexible, bipartite system that recruits a large uptake transporter as a sensory module and modulates its functionality to achieve a mechanistic coupling to a kinase domain in order to trigger downstream signaling events.


Asunto(s)
Compuestos de Amonio/metabolismo , Proteínas Bacterianas/metabolismo , Membrana Celular/metabolismo , Histidina Quinasa/metabolismo , Transducción de Señal , Secuencia de Aminoácidos , Compuestos de Amonio/química , Bacterias/genética , Bacterias/metabolismo , Proteínas Bacterianas/genética , Sitios de Unión/genética , Cristalografía por Rayos X , Histidina Quinasa/química , Histidina Quinasa/genética , Proteínas de Transporte de Membrana/química , Proteínas de Transporte de Membrana/genética , Proteínas de Transporte de Membrana/metabolismo , Modelos Moleculares , Oxidación-Reducción , Unión Proteica , Dominios Proteicos , Dispersión del Ángulo Pequeño , Homología de Secuencia de Aminoácido , Difracción de Rayos X
13.
Respir Med ; 109(7): 882-9, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25952774

RESUMEN

BACKGROUND: Exercise impairment is a central feature of chronic obstructive pulmonary disease (COPD), and a minimal clinically important difference (MCID) for 6-min walk distance (6MWD) decline (>30 m) has been associated with increased mortality. The predictors of the MCID are not fully known. We hypothesize that physiological factors and radiographic measures predict the MCID. METHODS: We assessed 121 COPD subjects during 2 years using clinical variables, computed tomographic (CT) measures of emphysema, and functional measures including diffusion lung capacity for carbon monoxide (DLCO). The association between an MCID for 6MWD and clinical, CT, and physiologic predictors was assessed using logistic analysis. The C-statistic was used to assess the predictive ability of the models. RESULTS: Forty seven (39%) subjects had an MCID. In an imaging-based model, log emphysema and age were the best predictors of MCID (emphysema Odds Ratio [OR] 2.47 95%CI [1.28-4.76]). In a physiologic model, DLCO, age, and male gender were selected the best predictors (DLCO OR 1.19 [1.08-1.31]). The C-statistic for the ability of these models to predict an MCID was 0.71 and 0.75, respectively. CONCLUSION: In COPD patients the burden of emphysema on CT scan and DLCO predict a clinically meaningful decline in exercise capacity.


Asunto(s)
Monóxido de Carbono/metabolismo , Tolerancia al Ejercicio/fisiología , Capacidad de Difusión Pulmonar/métodos , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Enfisema Pulmonar/etiología , Caminata , Anciano , Femenino , Estudios de Seguimiento , Volumen Espiratorio Forzado , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Enfermedad Pulmonar Obstructiva Crónica/metabolismo , Enfisema Pulmonar/diagnóstico , Enfisema Pulmonar/fisiopatología , Tomografía Computarizada por Rayos X
14.
Bol. malariol. salud ambient ; 49(2): 223-239, dic. 2009. ilus, tab
Artículo en Español | LILACS | ID: lil-630409

RESUMEN

Colectas e identificaciones realizadas en un área de transmisión malárica en el estado Sucre, Venezuela, mostraron mediante el uso de las claves ad hoc, la posible presencia en simpatría de poblaciones de Anopheles aquasalis Curry y An. benarrochi Gabaldón, Cova-García & López. Adicionalmente, se detectaron poblaciones de individuos que mostraron mezcla de los caracteres diagnósticos señalados en las claves. Debido a la importancia epidemiológica que representan ambas especies en dicha zona malárica, este estudio se orientó hacia la determinación de las tres entidades señaladas, mediante filogenia molecular con las secuencias de ADN mitocondrial (region Citocromo Oxidasa 1). En este sentido, el concepto de especie filogenética fue evaluada utilizando análisis de parsimonia máxima que mostraron politomías (nodos no resueltos) fuertemente apoyadas entre las secuencias inclusive la del haplotipo proveniente de un macho identificado como aquasalis, mostrando hipótesis (árboles) totales sin resolución ni apoyo de grupos internos con los tres morfotipos como un grupo natural único. Las distancias genéticas (Kimura-2P) mostraron que la variablidad inter-morfotipos están dentro de la varianza intra sugiriendo que los haplotipos problema son una única entidad polimórfica y con plasticidad fenotípica. Se concluye que An. aquasalis es la entidad única de las poblaciones estudiadas y que los caracteres morfológicos como: 1) vena Medial con escamas negras y 2) palpos maxilares con superficie ventral cubierta de escamas blancas, que son propuestas en la mayoría de las claves no son caracteres válidos para la identificación de hembras de An. benarrochi y que tales caracteres forman parte de la variación intraespecífica en An. aquasalis. Esta conclusión apoya la revisión de Faran (1980), quién no propone caracteres diferenciales para hembras de ambas especies, siendo indistinguibles por medio de los caracteres morfológicos tradicionalmente utilizados.


Collected specimens from a malaric area in Sucre State, Venezuela, using the ad hoc Keys, were identified as Anopheles aquasalis Curry and An. benarrochi Gabaldón, Cova-García & López populations. Additionally, other individuals have shown a mixture of diagnostic characters of both species. As a consequence of the epidemiological importance that both species represent in this malaric area and its correct identification for vector control aims, we addressed the research to the determination of both entities by mean of phylogenetic methods using mitochondrial DNA (Cytochrome Oxidase 1) from these three entities. In order to evaluate the phylogenetic species concept, the Maximum Parsimony analyses showed strong supported politomies (unresolved nodes), yielded solutions with no supported groups correlated with two or three morphological entities including the male haplotype identified as An. aquasalis. The genetic distances (K-2P) showed that the variability inter-morphotype is in the variance intra, suggesting that the haplotypes belong to the three morphotypes and represent a unique polymorphic species with phenotypic plasticity. We conclude that An. aquasalis is a unique taxonomic entity in the populations studied and also that the morphological characters such as: 1) medial vein with black scales and 2) maxillary palpus with ventral surface covered with white scales, proposed in most of the keys used are not valid characters to distinguish females of An. benarrochi from An. aquasalis as these characters belong to the intra-specific variation of An. aquasalis. This conclusion supports the Faran (1980) key, which did not report any morphological characters, showing undistinguished females under classical characters used


Asunto(s)
Animales , ADN Mitocondrial/análisis , Anopheles/anatomía & histología , Anopheles/clasificación , Anopheles/parasitología , Salud Ambiental , Malaria
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