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1.
Nature ; 606(7915): 674-677, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35676480

RESUMEN

Solar flares, driven by prompt release of free magnetic energy in the solar corona1,2, are known to accelerate a substantial portion (ten per cent or more)3,4 of available electrons to high energies. Hard X-rays, produced by high-energy electrons accelerated in the flare5, require a high ambient density for their detection. This restricts the observed volume to denser regions that do not necessarily sample the entire volume of accelerated electrons6. Here we report evolving spatially resolved distributions of thermal and non-thermal electrons in a solar flare derived from microwave observations that show the true extent of the acceleration region. These distributions show a volume filled with only (or almost only) non-thermal electrons while being depleted of the thermal plasma, implying that all electrons have experienced a prominent acceleration there. This volume is isolated from a surrounding, more typical flare plasma of mainly thermal particles with a smaller proportion of non-thermal electrons. This highly efficient acceleration happens in the same volume in which the free magnetic energy is being released2.

2.
Rheumatology (Oxford) ; 63(4): 1153-1161, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-37481711

RESUMEN

OBJECTIVES: DISH is a common musculoskeletal disorder; however, the imaging features and disease continuum from early to advanced stages is poorly understood. The purpose of this study was to evaluate the prevalence of DISH and early-phase DISH in an American population and to assess the extent and pattern of ectopic mineralization across the thoracic spine. METHODS: Data were retrieved in collaboration with the Rochester Epidemiology Project. We conducted a retrospective image evaluation of a sample of individuals over 19 years of age with CT of the thoracic spine from a Northern US catchment area. Stratified random sampling by age and sex was used to populate the study. We examined the prevalence and extent of ectopic mineralization along the thoracic spine using previously established criteria. RESULTS: A total of 1536 unique images (766 female and 770 male individuals) including 16 710 motion segments were evaluated for imaging features of the continuum of DISH. Collectively, 40.5% of all motion segments evaluated displayed evidence of ectopic mineralization in the thoracic spine. The prevalence of early-phase DISH was 13.2% (10.4% of female and 15.8% of male individuals). The prevalence of established DISH was 14.2% (7.4% of female and 20.9% of male individuals). Remarkable heterogeneity was detected in individuals within each disease classification, based on the extent of the thoracic spine affected and degree of mineralization. CONCLUSIONS: The continuum of imaging features associated with DISH is detected in more than one in four adults and both sexes in an American population.


Asunto(s)
Hiperostosis Esquelética Difusa Idiopática , Adulto , Humanos , Masculino , Femenino , Hiperostosis Esquelética Difusa Idiopática/diagnóstico por imagen , Hiperostosis Esquelética Difusa Idiopática/epidemiología , Estudios Retrospectivos , Longevidad , Prevalencia , Tomografía Computarizada por Rayos X/métodos
3.
Crit Rev Toxicol ; 53(2): 69-116, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-37278976

RESUMEN

Acrylonitrile (ACN) is a known rodent and possible human carcinogen. There have also been concerns as to it causing adverse reproductive health effects. Numerous genotoxicity studies at the somatic level in a variety of test systems have demonstrated ACN's mutagenicity; its potential to induce mutations in germ cells has also been evaluated. ACN is metabolized to reactive intermediates capable of forming adducts with macromolecules including DNA, a necessary first step in establishing a direct mutagenic mode of action (MOA) for its carcinogenicity. The mutagenicity of ACN has been well demonstrated, however, numerous studies have found no evidence for the capacity of ACN to induce direct DNA lesions that initiate the mutagenic process. Although ACN and its oxidative metabolite (2-cyanoethylene oxide or CNEO) have been shown to bind in vitro with isolated DNA and associated proteins, usually under non-physiological conditions, studies in mammalian cells or in vivo have provided little specification as to an ACN-DNA reaction. Only one early study in rats has shown an ACN/CNEO DNA adduct in liver, a non-target tissue for its carcinogenicity in the rat. By contrast, numerous studies have shown that ACN can act indirectly to induce at least one DNA adduct by forming reactive oxygen species (ROS) in vivo, but it has not been definitively shown that the resulting DNA damage is causative for the induction of mutations. Genotoxicity studies for ACN in somatic and germinal cells are summarized and critically reviewed. Significant data gaps have been identified for bringing together the massive data base that provides the basis of ACN's current genotoxicity profile.


Asunto(s)
Acrilonitrilo , Mutágenos , Ratas , Humanos , Animales , Mutágenos/toxicidad , Aductos de ADN , Acrilonitrilo/toxicidad , Pruebas de Mutagenicidad , Daño del ADN , ADN , Mamíferos
4.
Mol Pharm ; 20(1): 147-158, 2023 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-36367432

RESUMEN

It is well known that reduced gastric acidity, for example with concomitant administration of acid reducing agents, can result in variable pharmacokinetics and decreased absorption of weakly basic drugs. It is important to identify the risk of reduced and variable absorption early in development, so that product design options to address the risk can be considered. This article describes the utilization of in vitro and in silico tools to predict the effect of gastric pH, as well as the impact of adding pH modifiers, in mitigating the effect of acid reducing agents on weak base drugs' dissolution and absorption. Palbociclib, a weakly basic drug, was evaluated in low and high gastric pH conditions in a multicompartmental dissolution apparatus referred to as a gastrointestinal simulator (GIS). The GIS permits the testing of pharmaceutical products in a way that better assesses dissolution under physiologically relevant conditions of pH, buffer concentration, formulation additives, and physiological variations including GI pH, buffer concentrations, secretions, stomach emptying rate, residence time in the GI, and aqueous luminal volume. To predict drug dissolution in the GIS, a hierarchical mass transport model was used and validated using in vitro experimental data. Dissolution results were then compared to observed human clinical plasma data with and without proton pump inhibitors using a GastroPlus absorption model to predict palbociclib plasma profiles and pharmacokinetic parameters. The results showed that the in silico model successfully predicted palbociclib dissolution in the GIS under low and high gastric pH conditions with and without pH modifiers. Furthermore, the GIS data coupled with the in silico tools anticipated (1) the reduced palbociclib exposure due to proton pump inhibitor coadministration and (2) the mitigating effect of a pH-modifying agent. This study provides tools to help in the development of orally administered formulations to overcome the effect of elevated gastric pH, especially when formulating with pH modifiers.


Asunto(s)
Absorción Intestinal , Sustancias Reductoras , Humanos , Sustancias Reductoras/farmacología , Solubilidad , Concentración de Iones de Hidrógeno , Administración Oral , Preparaciones Farmacéuticas , Simulación por Computador , Absorción Intestinal/fisiología , Modelos Biológicos
5.
Prev Med ; 175: 107724, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37827208

RESUMEN

OBJECTIVE: This study aimed to determine the longitudinal associations between self-reported sleep duration and cardiometabolic disease (CMD) risk in corporate executives. METHODS: Self-reported sleep duration and lifestyle, occupational, psychological, and anthropometrical, blood pressure and blood marker variables were obtained from 1512 employees at annual health risk assessments in South Africa between 2016 and 2019. Gender-stratified linear mixed models, adjusting for age, lifestyle, occupational and psychological covariates were used to explore these longitudinal associations. RESULTS: Among women, shorter sleep duration was associated with higher body mass index (BMI) covarying for age only (ß with 95% confidence intervals: -0.19 [-0.36, -0.03]), age and occupational factors (-0.20 [-0.36, -0.03]) and age and psychological factors (-0.20 [-0.37, -0.03]). Among men, shorter sleep was associated with both BMI and waist circumference (WC) covarying for age only (BMI: -0.15 [-0.22; -0.08]; WC: -0.62 [-0.88; -0.37]); age and lifestyle factors (BMI: -0.12 [-0.21; -0.04]); WC: -0.016 [-0.92; -0.29], age and occupational factors (BMI: -0.20 [-0.22; 0.08]; WC: -0.62 [-0.88; -0.36]), and age and psychological factors (BMI: -0.15 [-0.22; -0.07]; WC: -0.59 [-0.86; -0.33]). Among men, shorter sleep was also longitudinally associated with higher CMD risk scores in models adjusted for age and lifestyle factors (CMD: -0.12 [-0.20; -0.04]) and age and psychological factors (CMD: -0.08 [-0.15; -0.01]). CONCLUSION: Corporate executives who report shorter sleep durations may present with poorer CMD risk profiles, independent of age, lifestyle, occupational and psychological factors. Addressing sleep health in workplace health programmes may help mitigate the development of CMD in such employees.


Asunto(s)
Enfermedades Cardiovasculares , Trastornos del Sueño-Vigilia , Masculino , Humanos , Femenino , Autoinforme , Duración del Sueño , Factores de Riesgo , Sueño , Índice de Masa Corporal , Circunferencia de la Cintura , Enfermedades Cardiovasculares/epidemiología
6.
J Pineal Res ; 74(1): e12838, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36308745

RESUMEN

The increasing number of people living with human immunodeficiency virus, HIV, (PLWH) have an elevated incidence of risk for noncommunicable comorbidities, the aetiology of which remains incompletely understood. While sleep disturbances are often reported in PLWH, it is unknown to what extent they relate to changes in the circadian and/or sleep homeostatic processes. We studied the relationship between sleep characteristics, circadian phase, and HIV status in older adults from the HAALSI (Health and Ageing in Africa: a Longitudinal Study of an INDEPTH Community in South Africa) subsample of the Agincourt Health and Demographic Surveillance System in South Africa (n = 187, 36 human immunodeficiency virus positive [HIV+], age: 66.7 ± 11.5 years, range 45-93 years), where HIV prevalence is high and (in contrast to the global north) does not associate significantly with potentially confounding behavioural differences. In participants with valid actigraphy data (n = 172), regression analyses adjusted for age and sex indicated that HIV+ participants had slightly later sleep onset (ß = .16, p = .039), earlier sleep offset times (ß = -.16, p = .049) and shorter total sleep times (ß = -.20, p = .009) compared to the HIV negative (HIV-) participants. In a subset of participants (n = 51, 11 HIV+), we observed a later dim light melatonin onset (DLMO) in HIV+ (21:16 ± 01:47) than in HIV- (20:06 ± 00:58) participants (p = .006). This substantial difference remained when adjusted for age and sex (ß = 1.21; p = .006). In 36 participants (6 HIV+) with DLMO and actigraphy data, median phase angle of entrainment was -6 min in the HIV+ group and +1 h 25 min in the HIV- group. DLMO time correlated with sleep offset (ρ = 0.47, p = .005) but not sleep onset (ρ = -0.086, p = .623). Collectively, our data suggest that the sleep phase occurred earlier than what would be biologically optimal among the HIV+ participants. This is the first report of a mistimed circadian phase in PLWH, which has important potential implications for their health and well-being, especially given the well-established relationships between circadian asynchrony and sleep deprivation with poorer health outcomes.


Asunto(s)
Infecciones por VIH , Melatonina , Humanos , Anciano , Persona de Mediana Edad , Anciano de 80 o más Años , Estudios Longitudinales , VIH , Pueblo Africano , Ritmo Circadiano , Infecciones por VIH/epidemiología
7.
BMC Infect Dis ; 23(1): 861, 2023 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-38062372

RESUMEN

BACKGROUND: HIV has become a manageable chronic condition due to the success and scale-up of antiretroviral therapy (ART). Globally, South Africa has the highest number of people living with HIV (PLHIV) and research evidence indicates that countries with the highest burden of PLHIV have a substantial burden of obesity, hypertension (HPT) and type 2 diabetes (T2D). We sought to summarize the burden of these three common NCDs among PLHIV in South Africa. METHODS: In this systematic review, multiple databases were searched for articles reporting on the prevalence of obesity, HPT, and T2D among PLHIV in South Africa published since journal inception until March 2022. A meta-analysis was conducted using random-effects models to obtain pooled prevalence estimates of the three NCDs. Heterogeneity was assessed using X2 test on Cochran's Q statistic. RESULTS: We included 32 studies, with 19, 22 and 18 studies reporting the prevalence of obesity, HPT, and T2D among PLHIV, respectively. The overall prevalence of obesity, HPT, and T2D was 23.2% [95% CI 17.6; 29.9], 25.5% [95% CI 15.6; 38.7], and 6.1% [95% CI 3.8; 9.7] respectively. The prevalence of obesity was significantly higher among women (P = 0.034) compared to men, however the prevalence of HPT and T2D did not differ by sex. The prevalence of each of the three NCDs did not differ significantly between rural, urban, and peri-urban areas. The prevalence of obesity and T2D was higher in studies conducted between 2013 and 2022 compared to studies conducted between 2000 and 2012, while the prevalence of HPT was higher between 2000 and 2012 compared to between 2013 and 2022. CONCLUSIONS: These findings suggest that South Africa is experiencing a syndemic of NCDs among people PLHIV highlighting the need to increase cost-effective interventions and management strategies that involve integrated HIV and NCD care in the South African setting.


Asunto(s)
Diabetes Mellitus Tipo 2 , Infecciones por VIH , Hipertensión , Masculino , Humanos , Femenino , Sudáfrica/epidemiología , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/epidemiología , Prevalencia , Hipertensión/epidemiología , Obesidad/complicaciones , Obesidad/epidemiología , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología
8.
J Behav Med ; 46(1-2): 9-14, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-35635594

RESUMEN

Extensive media coverage and potential controversy about COVID-19 vaccination during the pandemic may have affected people's general attitudes towards vaccination. We sought to describe key psychological antecedents related to vaccination and assess how these vary temporally in relationship to the pandemic and availability of COVID-19 vaccination. As part of an ongoing online study, we recruited a national (U.S.) sample of young gay, bisexual and other men who have sex with men (N = 1,227) between October 2019 and June 2021, and assessed the "4Cs" (antecedents of vaccination; range = 1-5). Overall, men had high levels of confidence (trust in vaccines; M = 4.13), calculation (deliberation; M = 3.97) and collective responsibility (protecting others; M = 4.05) and low levels of complacency (not perceiving disease risk; M = 1.72). In multivariable analyses, confidence and collective responsibility varied relative to the pandemic phase/vaccine availability, reflecting greater hesitancy during later stages of the pandemic. Antecedents also varied by demographic characteristics. Findings suggest negative effects of the COVID-19 pandemic on key antecedents of general vaccination and identify potential targets for interventions.


Asunto(s)
COVID-19 , Minorías Sexuales y de Género , Masculino , Humanos , COVID-19/prevención & control , Vacunas contra la COVID-19 , Homosexualidad Masculina , Pandemias , Vacilación a la Vacunación , Vacunación
9.
BMC Health Serv Res ; 23(1): 1384, 2023 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-38082293

RESUMEN

BACKGROUND: Normalization Process Theory (NPT) is an implementation theory that can be used to explain how and why implementation strategies work or not in particular circumstances. We used it to understand the mechanisms that lead to the adoption and routinization of palliative care within hemodialysis centers. METHODS: We employed a longitudinal, mixed methods approach to comprehensively evaluate the implementation of palliative care practices among ten hemodialysis centers participating in an Institute for Healthcare Improvement Breakthrough- Series learning collaborative. Qualitative methods included longitudinal observations of collaborative activities, and interviews with implementers at the end of the study. We used an inductive and deductive approach to thematic analysis informed by NPT constructs (coherence, cognitive participation, collective action, reflexive monitoring) and implementation outcomes. The NoMAD survey, which measures NPT constructs, was completed by implementers at each hemodialysis center during early and late implementation. RESULTS: The four mechanisms posited in NPT had a dynamic and layered relationship during the implementation process. Collaborative participants participated because they believed in the value and legitimacy of palliative care for patients receiving hemodialysis and thus had high levels of cognitive participation at the start. Didactic Learning Sessions were important for building practice coherence, and sense-making was solidified through testing new skills in practice and first-hand observation during coaching visits by an expert. Collective action was hampered by limited time among team members and practical issues such as arranging meetings with patients. Reflexive monitoring of the positive benefit to patient and family experiences was key in shifting mindsets from disease-centric towards a patient-centered model of care. NoMAD survey scores showed modest improvement over time, with collective action having the lowest scores. CONCLUSIONS: NPT was a useful framework for understanding the implementation of palliative care practices within hemodialysis centers. We found a nonlinear relationship among the mechanisms which is reflected in our model of implementation of palliative care practices through a learning collaborative. These findings suggest that the implementation of complex practices such as palliative care may be more successful through iterative learning and practice opportunities as the mechanisms for change are layered and mutually reinforcing. TRIAL REGISTRATION: ClinicalTrials.gov, NCT04125537 . Registered 14 October 2019 - Retrospectively registered.


Asunto(s)
Buceo , Cuidados Paliativos , Humanos , Natación , Atención a la Salud , Encuestas y Cuestionarios , Investigación Cualitativa
10.
Int J Mol Sci ; 24(2)2023 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-36675177

RESUMEN

Alzheimer's disease (AD) is a multifactorial, progressive, neurodegenerative disease typically characterized by memory loss, personality changes, and a decline in overall cognitive function. Usually manifesting in individuals over the age of 60, this is the most prevalent type of dementia and remains the fifth leading cause of death among Americans aged 65 and older. While the development of effective treatment and prevention for AD is a major healthcare goal, unfortunately, therapeutic approaches to date have yet to find a treatment plan that produces long-term cognitive improvement. Drugs that may be able to slow down the progression rate of AD are being introduced to the market; however, there has been no previous solution for preventing or reversing the disease-associated cognitive decline. Recent studies have identified several factors that contribute to the progression and severity of the disease: diet, lifestyle, stress, sleep, nutrient deficiencies, mental health, socialization, and toxins. Thus, increasing evidence supports dietary and other lifestyle changes as potentially effective ways to prevent, slow, or reverse AD progression. Studies also have demonstrated that a personalized, multi-therapeutic approach is needed to improve metabolic abnormalities and AD-associated cognitive decline. These studies suggest the effects of abnormalities, such as insulin resistance, chronic inflammation, hypovitaminosis D, hormonal deficiencies, and hyperhomocysteinemia, in the AD process. Therefore a personalized, multi-therapeutic program based on an individual's genetics and biochemistry may be preferable over a single-drug/mono-therapeutic approach. This article reviews these multi-therapeutic strategies that identify and attenuate all the risk factors specific to each affected individual. This article systematically reviews studies that have incorporated multiple strategies that target numerous factors simultaneously to reverse or treat cognitive decline. We included high-quality clinical trials and observational studies that focused on the cognitive effects of programs comprising lifestyle, physical, and mental activity, as well as nutritional aspects. Articles from PubMed Central, Scopus, and Google Scholar databases were collected, and abstracts were reviewed for relevance to the subject matter. Epidemiological, pathological, toxicological, genetic, and biochemical studies have all concluded that AD represents a complex network insufficiency. The research studies explored in this manuscript confirm the need for a multifactorial approach to target the various risk factors of AD. A single-drug approach may delay the progression of memory loss but, to date, has not prevented or reversed it. Diet, physical activity, sleep, stress, and environment all contribute to the progression of the disease, and, therefore, a multi-factorial optimization of network support and function offers a rational therapeutic strategy. Thus, a multi-therapeutic program that simultaneously targets multiple factors underlying the AD network may be more effective than a mono-therapeutic approach.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Enfermedades Neurodegenerativas , Humanos , Enfermedad de Alzheimer/patología , Enfermedades Neurodegenerativas/complicaciones , Disfunción Cognitiva/tratamiento farmacológico , Cognición , Trastornos de la Memoria/complicaciones
11.
Am J Transplant ; 22(11): 2571-2585, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35897156

RESUMEN

Allogeneic islet transplantation is a promising experimental therapy for poorly controlled diabetes. Despite pharmacological immunosuppression, long-term islet engraftment remains elusive. Here, we designed a synthetic fusion transgene coupling PD-L1 and indoleamine dioxygenase [hereafter PIDO] whose constitutive expression prevents immune destruction of genetically engineered islet allograft transplanted in immunocompetent mice. PIDO expressing murine islets maintain robust dynamic insulin secretion in vitro and when transplanted in allogeneic hyperglycemic murine recipients reverse pre-existing streptozotocin-induced and autoimmune diabetes in the absence of pharmacological immunosuppression for more than 50 and 8 weeks, respectively, and is dependent on host CD4 competence. Additionally, PIDO expression in allografts preserves endocrine functional viability of islets and promotes a localized tolerogenic milieu characterized by the suppression of host CD8 T cell and phagocyte recruitment and accumulation of FOXP3+ Tregs. Furthermore, in the canine model of xenogeneic islet transplantation, muscle implanted PIDO-expressing porcine islets displayed physiological glucose-responsive insulin secretion competency in euglycemic recipient for up to 20 weeks. In conclusion, the PIDO transgenic technology enables host CD4+ T cell-modulated immune evasiveness and long-term functional viability of islet allo- and xenografts in immune-competent recipients without the need for pharmacological immune suppression and would allow for improved outcomes for tissue transplantation.


Asunto(s)
Diabetes Mellitus Tipo 1 , Trasplante de Islotes Pancreáticos , Islotes Pancreáticos , Animales , Perros , Humanos , Ratones , Aloinjertos , Antígeno B7-H1/metabolismo , Rechazo de Injerto/prevención & control , Supervivencia de Injerto , Terapia de Inmunosupresión , Islotes Pancreáticos/metabolismo , Ratones Endogámicos C57BL , Porcinos , Indolamina-Pirrol 2,3,-Dioxigenasa
12.
Am J Kidney Dis ; 79(5): 699-708.e1, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-34648897

RESUMEN

RATIONALE & OBJECTIVE: Although guidelines recommend more and earlier advance care planning (ACP) for patients with chronic kidney disease (CKD), scant evidence exists to guide incorporation of ACP into clinical practice for patients with stages of CKD prior to kidney failure. Involving nephrology team members in addition to primary care providers in this important patient-centered process may increase its accessibility. Our study examined the effect of coaching implemented in CKD clinics on patient engagement with ACP. STUDY DESIGN: Multicenter, pragmatic randomized controlled trial. SETTING & PARTICIPANTS: Three CKD clinics in different states participated: 273 patients consented to participate, 254 were included in analysis. Eligible patients were 55 years or older, had stage 3-5 CKD, and were English speaking. INTERVENTION: Nurses or social workers with experience in nephrology or palliative care delivered individualized in-person ACP sessions. The enhanced control group was given Make Your Wishes About You (MY WAY) education materials and was verbally encouraged to bring their completed advance directives to the clinic. OUTCOME: Primary outcome measures were scores on a 45-point ACP engagement scale at 14 weeks and a documented advance directive or portable medical order at 16 weeks after enrollment. RESULTS: Among 254 participants analyzed, 46.5% were 65-74 years of age, and 54% had CKD stage 3. The coached patients scored 1.9 points higher at 14 weeks on the ACP engagement scale (ß = 1.87 [95% CI, 0.13-3.64]) adjusted for baseline score and site. Overall, 32.8% of intervention patients (41 of 125) had an advance directive compared with 17.8% (23 of 129) of patients in the control group. In a site-adjusted multivariable model, coached patients were 79% more likely to have a documented advance directive or portable medical order (adjusted risk ratio, 1.79 [95% CI, 1.18-2.72]), with the impact principally evident at only 1 study site. LIMITATIONS: Small number of study sites and possible unrepresentativeness of the broader CKD population by study participants. CONCLUSIONS: Individualized coaching may be effective in enhancing ACP, but its impact may be influenced by the health care environment where it is delivered. FUNDING: The Patrick and Catherine Weldon Donaghue Medical Research Foundation, via the Greater Value Portfolio. TRIAL REGISTRATION: Registered at ClinicalTrials.gov with study number NCT03506087.


Asunto(s)
Planificación Anticipada de Atención , Tutoría , Insuficiencia Renal Crónica , Directivas Anticipadas , Femenino , Humanos , Masculino , Participación del Paciente , Insuficiencia Renal Crónica/terapia
13.
Opt Express ; 30(8): 12294-12307, 2022 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-35472867

RESUMEN

Coupling characteristics between a single mode fiber (SMF) and a waveguide embedded in a glass chip via a graded index fiber (GIF) tip are investigated at a wavelength of 976 nm. The GIF tips comprise a coreless fiber section and a GIF section. A depressed cladding waveguide in a ZBLAN glass chip with a core diameter of 35 µm is coupled with GIF tips that have a range of coreless fiber and GIF lengths. An experimental coupling efficiency as high as 88% is obtained while a numerical simulation predicts 92.9% for the same GIF tip configuration. Since it is measured in the presence of Fresnel reflection, it can be further improved by anti-reflection coating. Additionally, it is demonstrated that a gap can be introduced between the chip waveguide and the GIF tip while maintaining the high coupling efficiency, thus allowing a thin planar optical component to be inserted. The results presented here will enable miniaturization and simplification of photonic chips with integrated waveguides by replacing bulk coupling lenses with integrated optical fibers.

14.
Int J Behav Nutr Phys Act ; 19(1): 82, 2022 07 10.
Artículo en Inglés | MEDLINE | ID: mdl-35818066

RESUMEN

BACKGROUND: Relationships between mental health and multiple health behaviours have not been explored in young South African women experiencing social constraints. The aim of this study was to identify associations between mental health indicators and risk factors with physical activity, sedentary behaviour, and sleep, amongst young women living in Soweto, a predominantly low-income, urban South African setting. METHODS: For this cross-sectional study, baseline measurements for participants (n = 1719, 18.0-25.9 years old) recruited for the Healthy Life Trajectories Initiative were used including: physical activity, sedentary behaviour (sitting, screen and television time), sleep (duration and quality), depression and anxiety indicators, emotional health, adverse childhood experiences, alcohol-use risk; social vulnerability, self-efficacy, and social support. RESULTS: Multiple regression analyses showed that depression (ß = 0.161, p < 0.001), anxiety (ß = 0.126, p = 0.001), adverse childhood experiences (ß = 0.076, p = 0.014), and alcohol-use risk (ß = 0.089, p = 0.002) were associated with poor quality sleep. Alcohol-use risk was associated with more screen time (ß = 0.105, p < 0.001) and television time (ß = 0.075, p < 0.016). Social vulnerability was associated with lower sitting time (ß = - 0.187, p < 0001) and screen time (ß = - 0.014, p < 0.001). Higher self-efficacy was associated with more moderate- to vigorous-intensity physical activity (ß = 0.07, p = 0.036), better-quality sleep (ß = - 0.069, p = 0.020) and less television time (ß = - 0.079, p = 0.012). Having no family support was associated with more sitting time (ß = 0.075, p = 0.022). Binomial logistic regression analyses supported these findings regarding sleep quality, with anxiety and depression risk doubling the risk of poor-quality sleep (OR = 2.425, p < 0.001, OR = 2.036, p = 0.003 respectively). CONCLUSIONS: These findings contribute to our understanding of how mental health indicators and risk factors can be barriers to health behaviours of young women in Soweto, and that self-efficacy and social support can be protective for certain of these behaviours for these women. Our results highlight the uniqueness of this setting regarding associations between mental health and behaviours associated with non-communicable diseases risk.


Asunto(s)
Salud Mental , Conducta Sedentaria , Adolescente , Adulto , Estudios Transversales , Ejercicio Físico , Femenino , Humanos , Sueño , Vulnerabilidad Social , Sudáfrica , Adulto Joven
15.
BMC Palliat Care ; 21(1): 129, 2022 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-35841019

RESUMEN

BACKGROUND: Patients undergoing hemodialysis have a high mortality rate and yet underutilize palliative care and hospice resources. The Shared Decision Making-Renal Supportive Care (SDM-RSC) intervention focused on goals of care conversations between patients and family members with the nephrologist and social worker. The intervention targeted deficiencies in communication, estimating prognosis, and transition planning for seriously ill dialysis patients. The intervention showed capacity to increase substantially completion of advance care directives. The HIGHway Project, adapted from the previous SDM-RSC, scale up training social workers or nurses in dialysis center in advance care planning (ACP), and then support them for a subsequent 9-month action period, to engage in ACP conversations with patients at their dialysis center regarding their preferences for end-of-life care. METHODS: We will train between 50-60 dialysis teams, led by social workers or nurses, to engage in ACP conversations with patients at their dialysis center regarding their preferences for end-of-life care. This implementation project uses the Knowledge to Action (KTA) Framework within the Consolidated Framework for Implementation Research (CFIR) to increase adoption and sustainability in the participating dialysis centers. This includes a curriculum about how to hold ACP conversation and coaching with monthly teleconferences through case discussion and mentoring. An application software will guide on the process and provide resources for holding ACP conversations. Our project will focus on implementation outcomes. Success will be determined by adoption and effective use of the ACP approach. Patient and provider outcomes will be measured by the number of ACP conversations held and documented; the quality and fidelity of ACP conversations to the HIGHway process as taught during education sessions; impact on knowledge and skills; content, relevance, and significance of ACP intervention for patients, and Supportive Kidney Care (SKC) App usage. Currently HIGHway is in the recruitment stage. DISCUSSION: Effective changes to advance care planning processes in dialysis centers can lead to institutional policy and protocol changes, providing a model for patients receiving dialysis treatment in the US. The result will be a widespread improvement in advance care planning, thereby remedying one of the current barriers to patient-centered, goal-concordant care for dialysis patients. TRIAL REGISTRATION: The George Washington University Protocol Record NCR213481, Honoring Individual Goals and Hopes: Implementing Advance Care Planning for Persons with Kidney Disease on Dialysis, is registered in ClinicalTrials.gov Identifier: NCT05324878 on April 11th, 2022.


Asunto(s)
Planificación Anticipada de Atención , Cuidado Terminal , Directivas Anticipadas , Humanos , Nefrólogos , Diálisis Renal/métodos , Cuidado Terminal/métodos
16.
Microsc Microanal ; : 1-12, 2022 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-36052846

RESUMEN

Electron-excited X-ray microanalysis with energy-dispersive spectrometry (EDS) proceeds through the application of the software that extracts characteristic X-ray intensities and performs corrections for the physics of electron and X-ray interactions with matter to achieve quantitative elemental analysis. NIST DTSA-II is an open-access, fully documented, and freely available comprehensive software platform for EDS quantification, measurement optimization, and spectrum simulation. Spectrum simulation with DTSA-II enables the prediction of the EDS spectrum from any target composition for a specified electron dose and for the solid angle and window parameters of the EDS spectrometer. Comparing the absolute intensities for measured and simulated spectra reveals correspondence within ±25% relative to K-shell and L-shell characteristic X-ray peaks in the range of 1­11 keV. The predicted M-shell intensity exceeds the measured value by a factor of 1.4­2.2 in the range 1­3 keV. The X-ray continuum (bremsstrahlung) generally agrees within ±10% over the range of 1­10 keV. Simulated EDS spectra are useful for developing an analytical strategy for challenging problems such as estimating trace detection levels.

17.
Am J Physiol Renal Physiol ; 320(1): F31-F46, 2021 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-33135480

RESUMEN

Bacterial infection is one known etiology of prostatic inflammation. Prostatic inflammation is associated with prostatic collagen accumulation and both are linked to progressive lower urinary tract symptoms in men. We characterized a model of prostatic inflammation using transurethral instillations of Escherichia coli UTI89 in C57BL/6J male mice with the goal of determining the optimal instillation conditions, understanding the impact of instillation conditions on urinary physiology, and identifying ideal prostatic lobes and collagen 1a1 prostatic cell types for further analysis. The smallest instillation volume tested (50 µL) distributed exclusively to the bladder, 100- and 200-µL volumes distributed to the bladder and prostate, and a 500-µL volume distributed to the bladder, prostate, and ureter. A threshold optical density of 0.4 E. coli UTI89 in the instillation fluid was necessary for significant (P < 0.05) prostate colonization. E. coli UTI89 infection resulted in a low frequency, high volume spontaneous voiding pattern. This phenotype was due to exposure to E. coli UTI89, not catheterization alone, and was minimally altered by a 50-µL increase in instillation volume and doubling of E. coli concentration. Prostate inflammation was isolated to the dorsal prostate and was accompanied by increased collagen density. This was partnered with increased density of protein tyrosine phosphatase receptor type C+, procollagen type I-α1+ copositive cells and decreased density of α2-smooth muscle actin+, procollagen type I-α1+ copositive cells. Overall, we determined that this model is effective in altering urinary phenotype and producing prostatic inflammation and collagen accumulation in mice.


Asunto(s)
Colágeno Tipo I/metabolismo , Infecciones por Escherichia coli/microbiología , Procolágeno/metabolismo , Próstata/microbiología , Prostatitis/microbiología , Escherichia coli Uropatógena/patogenicidad , Actinas/metabolismo , Animales , Cadena alfa 1 del Colágeno Tipo I , Modelos Animales de Enfermedad , Infecciones por Escherichia coli/complicaciones , Antígenos Comunes de Leucocito/metabolismo , Masculino , Ratones Endogámicos C57BL , Próstata/metabolismo , Próstata/patología , Prostatitis/metabolismo , Prostatitis/patología , Técnicas de Cultivo de Tejidos
18.
Am J Physiol Renal Physiol ; 321(1): F82-F92, 2021 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-34121451

RESUMEN

We used male BTBR mice carrying the Lepob mutation, which are subject to severe and progressive obesity and diabetes beginning at 6 wk of age, to examine the influence of one specific manifestation of sleep apnea, intermittent hypoxia (IH), on male urinary voiding physiology and genitourinary anatomy. A custom device was used to deliver continuous normoxia (control) or IH to wild-type and Lepob/ob (mutant) mice for 2 wk. IH was delivered during the 12-h inactive (light) period in the form of 90 s of 6% O2 followed by 90 s of room air. Continuous room air was delivered during the 12-h active (dark) period. We then evaluated genitourinary anatomy and physiology. As expected for the type 2 diabetes phenotype, mutant mice consumed more food and water, weighed more, and voided more frequently and in larger urine volumes. They also had larger bladder volumes but smaller prostates, seminal vesicles, and urethras than wild-type mice. IH decreased food consumption and increased bladder relative weight independent of genotype and increased urine glucose concentration in mutant mice. When evaluated based on genotype (normoxia + IH), the incidence of pathogenic bacteriuria was greater in mutant mice than in wild-type mice, and among mice exposed to IH, bacteriuria incidence was greater in mutant mice than in wild-type mice. We conclude that IH exposure and type 2 diabetes can act independently and together to modify male mouse urinary function. NEW & NOTEWORTHY Metabolic syndrome and obstructive sleep apnea are common in aging men, and both have been linked to urinary voiding dysfunction. Here, we show that metabolic syndrome and intermittent hypoxia (a manifestation of sleep apnea) have individual and combined influences on voiding function and urogenital anatomy in male mice.


Asunto(s)
Diabetes Mellitus Tipo 2/metabolismo , Hipoxia/metabolismo , Síndrome Metabólico/metabolismo , Obesidad/metabolismo , Animales , Diabetes Mellitus Tipo 2/genética , Modelos Animales de Enfermedad , Hipoxia/genética , Resistencia a la Insulina/fisiología , Hígado/metabolismo , Masculino , Síndrome Metabólico/genética , Ratones , Obesidad/genética
19.
Prostate ; 81(13): 944-955, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34288015

RESUMEN

BACKGROUND: Little is known about how benign prostatic hyperplasia (BPH) develops and why patients respond differently to medical therapy designed to reduce lower urinary tract symptoms (LUTS). The Medical Therapy of Prostatic Symptoms (MTOPS) trial randomized men with symptoms of BPH and followed response to medical therapy for up to 6 years. Treatment with a 5α-reductase inhibitor (5ARI) or an alpha-adrenergic receptor antagonist (α-blocker) reduced the risk of clinical progression, while men treated with combination therapy showed a 66% decrease in risk of progressive disease. However, medical therapies for BPH/LUTS are not effective in many patients. The reasons for nonresponse or loss of therapeutic response in the remaining patients over time are unknown. A better understanding of why patients fail to respond to medical therapy may have a major impact on developing new approaches for the medical treatment of BPH/LUTS. Prostaglandins (PG) act on G-protein-coupled receptors (GPCRs), where PGE2 and PGF2 elicit smooth muscle contraction. Therefore, we measured PG levels in the prostate tissue of BPH/LUTS patients to assess the possibility that this signaling pathway might explain the failure of medical therapy in BPH/LUTS patients. METHOD: Surgical BPH (S-BPH) was defined as benign prostatic tissue collected from the transition zone (TZ) of patients who failed medical therapy and underwent surgical intervention to relieve LUTS. Control tissue was termed Incidental BPH (I-BPH). I-BPH was TZ obtained from men undergoing radical prostatectomy for low-volume, low-grade prostatic adenocarcinoma (PCa, Gleason score ≤ 7) confined to the peripheral zone. All TZ tissue was confirmed to be cancer-free. S-BPH patients divided into four subgroups: patients on α-blockers alone, 5ARI alone, combination therapy (α-blockers plus 5ARI), or no medical therapy (none) before surgical resection. I-BPH tissue was subgrouped by prior therapy (either on α-blockers or without prior medical therapy before prostatectomy). We measured prostatic tissue levels of prostaglandins (PGF2α , PGI2 , PGE2 , PGD2 , and TxA2 ), quantitative polymerase chain reaction levels of mRNAs encoding enzymes within the PG synthesis pathway, cellular distribution of COX1 (PTGS1) and COX2 (PTGS2), and tested the ability of PGs to contract bladder smooth muscle in an in vitro assay. RESULTS: All PGs were significantly elevated in TZ tissues from S-BPH patients (n = 36) compared to I-BPH patients (n = 15), regardless of the treatment subgroups. In S-BPH versus I-BPH, mRNA for PG synthetic enzymes COX1 and COX2 were significantly elevated. In addition, mRNA for enzymes that convert the precursor PGH2 to metabolite PGs were variable: PTGIS (which generates PGI2 ) and PTGDS (PGD2 ) were significantly elevated; nonsignificant increases were observed for PTGES (PGE2 ), AKR1C3 (PGF2α ), and TBxAS1 (TxA2 ). Within the I-BPH group, men responding to α-blockers for symptoms of BPH but requiring prostatectomy for PCa did not show elevated levels of COX1, COX2, or PGs. By immunohistochemistry, COX1 was predominantly observed in the prostatic stroma while COX2 was present in scattered luminal cells of isolated prostatic glands in S-BPH. PGE2 and PGF2α induced contraction of bladder smooth muscle in an in vitro assay. Furthermore, using the smooth muscle assay, we demonstrated that α-blockers that inhibit alpha-adrenergic receptors do not appear to inhibit PG stimulation of GPCRs in bladder muscle. Only patients who required surgery to relieve BPH/LUTS symptoms showed significantly increased tissue levels of PGs and the PG synthetic enzymes. CONCLUSIONS: Treatment of BPH/LUTS by inhibition of alpha-adrenergic receptors with pharmaceutical α-blockers or inhibiting androgenesis with 5ARI may fail because of elevated paracrine signaling by prostatic PGs that can cause smooth muscle contraction. In contrast to patients who fail medical therapy for BPH/LUTS, control I-BPH patients do not show the same evidence of elevated PG pathway signaling. Elevation of the PG pathway may explain, in part, why the risk of clinical progression in the MTOPS study was only reduced by 34% with α-blocker treatment.


Asunto(s)
Síntomas del Sistema Urinario Inferior/tratamiento farmacológico , Prostaglandinas/metabolismo , Próstata/metabolismo , Hiperplasia Prostática/tratamiento farmacológico , Inhibidores de 5-alfa-Reductasa/uso terapéutico , Antagonistas Adrenérgicos alfa/uso terapéutico , Anciano , Humanos , Síntomas del Sistema Urinario Inferior/etiología , Síntomas del Sistema Urinario Inferior/metabolismo , Masculino , Persona de Mediana Edad , Hiperplasia Prostática/complicaciones , Hiperplasia Prostática/metabolismo , Insuficiencia del Tratamiento
20.
Cancer ; 127(6): 884-893, 2021 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-33197285

RESUMEN

BACKGROUND: The objective of this study was to report on the long-term effects of pexidartinib on tenosynovial giant cell tumor (TGCT). METHODS: This was a pooled analysis encompassing 3 pexidartinib-treated TGCT cohorts: 1) a phase 1 extension study (NCT01004861; 1000 mg/d; n = 39), 2) ENLIVEN patients randomized to pexidartinib (1000 mg/d for 2 weeks and then 800 mg/d; n = 61), and 3) ENLIVEN crossover patients (NCT02371369; 800 mg/d; n = 30). Eligible patients were 18 years old or older and had a histologically confirmed TGCT that was unresectable and symptomatic. Efficacy endpoints included the best overall response (complete or partial response) and the duration of response (DOR) by the Response Evaluation Criteria in Solid Tumors (RECIST) and the tumor volume score (TVS). The safety assessment included the frequency of treatment-emergent adverse events (TEAEs) and hepatic laboratory abnormalities (aminotransferase elevations and mixed/cholestatic hepatotoxicity). The data cutoff was May 31, 2019. RESULTS: One hundred thirty patients with TGCT received pexidartinib (median treatment duration, 19 months; range, 1 to 76+ months); 54 (42%) remained on treatment at the end of the analysis (26 months after initial data cut of March 2017). The RECIST overall response rate (ORR) was 60%; the TVS ORR was 65%. The median times to response were 3.4 (RECIST) and 2.8 months (TVS), with 48 of the responding patients (62%) achieving a RECIST partial response by 6 months and with 72 (92%) doing so by 18 months. The median DOR was reached for TVS (46.8 months). Reported TEAEs were mostly low-grade, with hair color changes being most frequent (75%). Most liver abnormalities (92%) were aminotransferase elevations; 4 patients (3%) experienced mixed/cholestatic hepatotoxicity (all within the first 2 months of treatment), which was reversible in all cases (recovery spanned 1-7 months). CONCLUSIONS: This study demonstrates the prolonged efficacy and tolerability of long-term pexidartinib treatment for TGCT.


Asunto(s)
Aminopiridinas/uso terapéutico , Tumor de Células Gigantes de las Vainas Tendinosas/tratamiento farmacológico , Pirroles/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Aminopiridinas/efectos adversos , Femenino , Tumor de Células Gigantes de las Vainas Tendinosas/patología , Humanos , Masculino , Persona de Mediana Edad , Pirroles/efectos adversos , Adulto Joven
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