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1.
Nephrol Dial Transplant ; 39(Supplement_2): ii3-ii10, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39235195

RESUMEN

BACKGROUND: Governance, health financing, and service delivery are critical elements of health systems for provision of robust and sustainable chronic disease care. We leveraged the third iteration of the International Society of Nephrology Global Kidney Health Atlas (ISN-GKHA) to evaluate oversight and financing for kidney care worldwide. METHODS: A survey was administered to stakeholders from countries affiliated with the ISN from July to September 2022. We evaluated funding models utilized for reimbursement of medications, services for the management of chronic kidney disease, and provision of kidney replacement therapy (KRT). We also assessed oversight structures for the delivery of kidney care. RESULTS: Overall, 167 of the 192 countries and territories contacted responded to the survey, representing 97.4% of the global population. High-income countries tended to use public funding to reimburse all categories of kidney care in comparison with low-income countries (LICs) and lower-middle income countries (LMICs). In countries where public funding for KRT was available, 78% provided universal health coverage. The proportion of countries that used public funding to fully reimburse care varied for non-dialysis chronic kidney disease (27%), dialysis for acute kidney injury (either hemodialysis or peritoneal dialysis) (44%), chronic hemodialysis (45%), chronic peritoneal dialysis (42%), and kidney transplant medications (36%). Oversight for kidney care was provided at a national level in 63% of countries, and at a state/provincial level in 28% of countries. CONCLUSION: This study demonstrated significant gaps in universal care coverage, and in oversight and financing structures for kidney care, particularly in in LICs and LMICs.


Asunto(s)
Atención a la Salud , Salud Global , Insuficiencia Renal Crónica , Humanos , Salud Global/economía , Atención a la Salud/economía , Insuficiencia Renal Crónica/terapia , Insuficiencia Renal Crónica/economía , Financiación de la Atención de la Salud , Terapia de Reemplazo Renal/economía , Países en Desarrollo , Cobertura Universal del Seguro de Salud/economía
2.
Nephrology (Carlton) ; 28(2): 109-118, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36401820

RESUMEN

AIM: Previous studies report an association between longer haemodialysis treatment sessions and improved survival. Worldwide, there is a trend to increasing age among prevalent patients receiving haemodialysis. This analysis aimed to determine whether the mortality benefit of longer haemodialysis treatment sessions diminishes with increasing age. METHODS: This was a retrospective cohort study of people who first commenced thrice-weekly haemodialysis aged ≥65 years, reported to the Australia and New Zealand Dialysis and Transplant (ANZDATA) Registry from 2005 to 2015, included from 90 days after dialysis start. The primary outcome was all-cause mortality. Cox regression analysis was performed with haemodialysis session duration the exposure of interest. RESULTS: Of 8224 people who commenced haemodialysis as their first treatment for kidney failure aged ≥65 years during this period, 4727 patients died. Longer dialysis hours per session was associated with a decreased risk of death in unadjusted analyses [hazard ratio, HR, for ≥5 h versus 4 to <4.5 h: 0.81 (0.75-0.88, p < .001)]. Patients having longer dialysis sessions were younger but had greater co-morbidity. In an adjusted model including age and other variables, the survival benefit of longer hours was only partially attenuated [HR for previous comparison: 0.75 (0.69-0.82, p < .001)], and no interaction between age and hours was demonstrated (p = .89). CONCLUSION: The apparent survival benefit associated with longer haemodialysis session length appears to be preserved in patients 65 years or older. In practice, the benefit of longer dialysis hours should be carefully weighed against other factors in this patient group.


Asunto(s)
Fallo Renal Crónico , Diálisis Renal , Humanos , Anciano , Diálisis Renal/efectos adversos , Fallo Renal Crónico/diagnóstico , Fallo Renal Crónico/terapia , Fallo Renal Crónico/epidemiología , Estudios Retrospectivos , Comorbilidad , Modelos de Riesgos Proporcionales
3.
J Fish Biol ; 103(4): 790-797, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36571486

RESUMEN

Invasive species have the potential to damage ecosystems outside their native range. At an invasion front, individuals are faced with the unfamiliar conditions of a novel environment. Therefore, certain behavioural traits such as boldness and movement likely play a role in invasion ecology. If behavioural traits of this kind are influenced by differing selection pressures between demographic groups of the same species, this could have broad implications for the management of expanding invasion fronts. To determine whether the invasive round goby (Neogobius melanostomus, Pallas, 1814) exhibits sex- and habitat-based differences in boldness and movement across the invasion front, the authors assessed individual movement and exploration tendency under controlled lab settings using video analysis in a behavioural assay. N. melanostomus from lakes tended to be bolder than those from streams, and females tended to be bolder than males. This study provides evidence for sex- and habitat-based differences in behaviour in this globally invasive species that the authors hope will assist in forming the foundation for contextually appropriate management strategies.


Asunto(s)
Ecosistema , Perciformes , Humanos , Femenino , Masculino , Animales , Ontario , Ecología , Fenotipo , Especies Introducidas
4.
Nephrol Dial Transplant ; 36(6): 1070-1077, 2021 05 27.
Artículo en Inglés | MEDLINE | ID: mdl-33306122

RESUMEN

BACKGROUND: Home haemodialysis (HHD) is utilized significantly less often than facility HD globally with few exceptions, despite being associated with improved survival and better quality of life. Previously HHD was exclusively offered to younger patients with a few comorbidities. However, with the increasing burden of end-stage kidney disease (ESKD) alongside an ageing population, increasing numbers of older patients are being treated with HHD. This study aims to re-evaluate survival and related outcomes in the context of this epidemiological shift. METHODS: A matched cohort design was used to compare all-cause mortality, transplantation, average biochemical values and graft survival 6 months post-transplant between HHD and facility HD patients. A total of 181 HHD patients from a major hospital network were included with 413 facility HD patients from the Australia and New Zealand Dialysis and Transplant Registry matched by age, gender and cause of ESKD. Survival analysis and competing risks analysis (for transplantation) were performed. RESULTS: After adjusting for body mass index, smoking status, racial group and comorbidities, HHD was associated with a significantly reduced risk of death compared with facility HD patients [hazard ratio 0.47 (95% confidence interval 0.30-0.74)]. Transplantation rates were comparable, with high rates of graft survival at 6 months in both groups. Haemoglobin, calcium and parathyroid hormone levels did not vary significantly. However, HHD patients had significantly lower phosphate levels. CONCLUSIONS: In this study, improved survival outcomes were observed in patients on home compared with facility dialysis, with comparable rates of transplantation, graft survival and biochemical control.


Asunto(s)
Fallo Renal Crónico , Calidad de Vida , Estudios de Cohortes , Hemodiálisis en el Domicilio , Humanos , Fallo Renal Crónico/terapia , Diálisis Renal
5.
Eur Heart J ; 37(8): 713-23, 2016 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-26491110

RESUMEN

AIMS: Midwall myocardial fibrosis on cardiovascular magnetic resonance (CMR) is a marker of early ventricular decompensation and adverse outcomes in aortic stenosis (AS). We aimed to develop and validate a novel clinical score using variables associated with midwall fibrosis. METHODS AND RESULTS: One hundred forty-seven patients (peak aortic velocity (Vmax) 3.9 [3.2,4.4] m/s) underwent CMR to determine midwall fibrosis (CMR cohort). Routine clinical variables that demonstrated significant association with midwall fibrosis were included in a multivariate logistic score. We validated the prognostic value of the score in two separate outcome cohorts of asymptomatic patients (internal: n = 127, follow-up 10.3 [5.7,11.2] years; external: n = 289, follow-up 2.6 [1.6,4.5] years). Primary outcome was a composite of AS-related events (cardiovascular death, heart failure, and new angina, dyspnoea, or syncope). The final score consisted of age, sex, Vmax, high-sensitivity troponin I concentration, and electrocardiographic strain pattern [c-statistic 0.85 (95% confidence interval 0.78-0.91), P < 0.001; Hosmer-Lemeshow χ(2) = 7.33, P = 0.50]. Patients in the outcome cohorts were classified according to the sensitivity and specificity of this score (both at 98%): low risk (probability score <7%), intermediate risk (7-57%), and high risk (>57%). In the internal outcome cohort, AS-related event rates were >10-fold higher in high-risk patients compared with those at low risk (23.9 vs. 2.1 events/100 patient-years, respectively; log rank P < 0.001). Similar findings were observed in the external outcome cohort (31.6 vs. 4.6 events/100 patient-years, respectively; log rank P < 0.001). CONCLUSION: We propose a clinical score that predicts adverse outcomes in asymptomatic AS patients and potentially identifies high-risk patients who may benefit from early valve replacement.


Asunto(s)
Estenosis de la Válvula Aórtica/patología , Miocardio/patología , Anciano , Estenosis de la Válvula Aórtica/mortalidad , Femenino , Fibrosis , Humanos , Angiografía por Resonancia Magnética , Masculino , Pronóstico , Medición de Riesgo/métodos , Análisis de Supervivencia
6.
Lipids Health Dis ; 14: 86, 2015 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-26256740

RESUMEN

BACKGROUND: Cardiovascular disease (CVD) remains the major cause of excess mortality in patients with non-alcoholic fatty liver disease (NAFLD). The aim of this study was to investigate the individual contribution of NAFLD to CVD risk factors in the absence of pathogenic influences from other comorbidities often found in NAFLD patients, by using an established in-vitro model of hepatic steatosis. METHODS: Histopathological events in non-alcoholic fatty liver disease were recapitulated by focused metabolic nutrient overload of hepatoblastoma C3A cells, using oleate-treated-cells and untreated controls for comparison. Microarray and proteomic data from cell culture experiments were integrated into a custom-built systems biology database and proteogenomics analysis performed. Candidate genes with significant dysregulation and concomitant changes in protein abundance were identified and STRING association and enrichment analysis performed to identify putative pathogenic pathways. RESULTS: The search strategy yielded 3 candidate genes that were specifically and significantly up-regulated in nutrient-overloaded cells compared to untreated controls: fibrinogen alpha chain (2.2 fold), fibrinogen beta chain (2.3 fold) and fibrinogen gamma chain (2.1 fold) (all rank products pfp <0.05). Fibrinogen alpha and gamma chain also demonstrated significant concomitant increases in protein abundance (3.8-fold and 2.0-fold, respectively, p <0.05). CONCLUSIONS: In-vitro modelling of NAFLD and reactive oxygen species formation in nutrient overloaded C3A cells, in the absence of pathogenic influences from other comorbidities, suggests that NAFLD is an isolated determinant of CVD. Nutrient overload-induced up-regulation of all three fibrinogen component subunits of the coagulation cascade provides a possible mechanism to explain the excess CVD mortality observed in NAFLD patients.


Asunto(s)
Enfermedades Cardiovasculares/etiología , Fibrinógeno/biosíntesis , Modelos Biológicos , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Línea Celular Tumoral , Farnesil Difosfato Farnesil Transferasa/metabolismo , Estudios de Asociación Genética , Humanos , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/patología , Análisis de Secuencia por Matrices de Oligonucleótidos , Proteómica , Factores de Riesgo , Transducción de Señal , Regulación hacia Arriba
7.
Lancet Glob Health ; 12(3): e382-e395, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38365413

RESUMEN

BACKGROUND: Since 2015, the International Society of Nephrology (ISN) Global Kidney Health Atlas (ISN-GKHA) has spearheaded multinational efforts to understand the status and capacity of countries to provide optimal kidney care, particularly in low-resource settings. In this iteration of the ISN-GKHA, we sought to extend previous findings by assessing availability, accessibility, quality, and affordability of medicines, kidney replacement therapy (KRT), and conservative kidney management (CKM). METHODS: A consistent approach was used to obtain country-level data on kidney care capacity during three phases of data collection in 2016, 2018, and 2022. The current report includes a detailed literature review of published reports, databases, and registries to obtain information on the burden of chronic kidney disease and estimate the incidence and prevalence of treated kidney failure. Findings were triangulated with data from a multinational survey of opinion leaders based on the WHO's building blocks for health systems (ie, health financing, service delivery, access to essential medicines and health technology, health information systems, workforce, and governance). Country-level data were stratified by the ISN geographical regions and World Bank income groups and reported as counts and percentages, with global, regional, and income level estimates presented as medians with interquartile ranges. FINDINGS: The literature review used information on prevalence of chronic kidney disease from 161 countries. The global median prevalence of chronic kidney disease was 9·5% (IQR 5·9-11·7) with the highest prevalence in Eastern and Central Europe (12·8%, 11·9-14·1). For the survey analysis, responses received covered 167 (87%) of 191 countries, representing 97·4% (7·700 billion of 7·903 billion) of the world population. Chronic haemodialysis was available in 162 (98%) of 165 countries, chronic peritoneal dialysis in 130 (79%), and kidney transplantation in 116 (70%). However, 121 (74%) of 164 countries were able to provide KRT to more than 50% of people with kidney failure. Children did not have access to haemodialysis in 12 (19%) of 62 countries, peritoneal dialysis in three (6%) countries, or kidney transplantation in three (6%) countries. CKM (non-dialysis management of people with kidney failure chosen through shared decision making) was available in 87 (53%) of 165 countries. The annual median costs of KRT were: US$19 380 per person for haemodialysis, $18 959 for peritoneal dialysis, and $26 903 for the first year of kidney transplantation. Overall, 74 (45%) of 166 countries allocated public funding to provide free haemodialysis at the point of delivery; use of this funding scheme increased with country income level. The median global prevalence of nephrologists was 11·8 per million population (IQR 1·8-24·8) with an 80-fold difference between low-income and high-income countries. Differing degrees of health workforce shortages were reported across regions and country income levels. A quarter of countries had a national chronic kidney disease-specific strategy (41 [25%] of 162) and chronic kidney disease was recognised as a health priority in 78 (48%) of 162 countries. INTERPRETATION: This study provides new information about the global burden of kidney disease and its treatment. Countries in low-resource settings have substantially diminished capacity for kidney care delivery. These findings have major policy implications for achieving equitable access to kidney care. FUNDING: International Society of Nephrology.


Asunto(s)
Atención a la Salud , Insuficiencia Renal Crónica , Niño , Humanos , Diálisis Renal , Insuficiencia Renal Crónica/epidemiología , Insuficiencia Renal Crónica/terapia , Costo de Enfermedad , Riñón
8.
Kidney Int Suppl (2011) ; 13(1): 110-122, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38618497

RESUMEN

The International Society of Nephrology (ISN) region of Oceania and South East Asia (OSEA) is a mix of high- and low-income countries, with diversity in population demographics and densities. Three iterations of the ISN-Global Kidney Health Atlas (GKHA) have been conducted, aiming to deliver in-depth assessments of global kidney care across the spectrum from early detection of CKD to treatment of kidney failure. This paper reports the findings of the latest ISN-GKHA in relation to kidney-care capacity in the OSEA region. Among the 30 countries and territories in OSEA, 19 (63%) participated in the ISN-GKHA, representing over 97% of the region's population. The overall prevalence of treated kidney failure in the OSEA region was 1203 per million population (pmp), 45% higher than the global median of 823 pmp. In contrast, kidney replacement therapy (KRT) in the OSEA region was less available than the global median (chronic hemodialysis, 89% OSEA region vs. 98% globally; peritoneal dialysis, 72% vs. 79%; kidney transplantation, 61% vs. 70%). Only 56% of countries could provide access to dialysis to at least half of people with incident kidney failure, lower than the global median of 74% of countries with available dialysis services. Inequalities in access to KRT were present across the OSEA region, with widespread availability and low out-of-pocket costs in high-income countries and limited availability, often coupled with large out-of-pocket costs, in middle- and low-income countries. Workforce limitations were observed across the OSEA region, especially in lower-middle-income countries. Extensive collaborative work within the OSEA region and globally will help close the noted gaps in kidney-care provision.

9.
Br J Hosp Med (Lond) ; 84(11): 1-2, 2023 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-38019199

RESUMEN

Octreotide is the cornerstone of perioperative management of neuroendocrine tumours, but there is no universal agreement on the optimal regimen. This article discusses the evidence for its use during different parts of the perioperative pathway.


Asunto(s)
Tumores Neuroendocrinos , Humanos , Tumores Neuroendocrinos/cirugía
10.
Dis Model Mech ; 16(9)2023 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-37655466

RESUMEN

Epigenetic processes have emerged as important modulators of kidney health and disease. Here, we studied the role of KDM6A (a histone demethylase that escapes X-chromosome inactivation) in kidney tubule epithelial cells. We initially observed an increase in tubule cell Kdm6a mRNA in male mice with unilateral ureteral obstruction (UUO). However, tubule cell knockout of KDM6A had relatively minor consequences, characterized by a small reduction in apoptosis, increase in inflammation and downregulation of the peroxisome proliferator-activated receptor (PPAR) signaling pathway. In proximal tubule lineage HK-2 cells, KDM6A knockdown decreased PPARγ coactivator-1α (PGC-1α) protein levels and mRNA levels of the encoding gene, PPARGC1A. Tubule cell Kdm6a mRNA levels were approximately 2-fold higher in female mice than in male mice, both under sham and UUO conditions. However, kidney fibrosis after UUO was similar in both sexes. The findings demonstrate Kdm6a to be a dynamically regulated gene in the kidney tubule, varying in expression levels by sex and in response to injury. Despite the context-dependent variation in Kdm6a expression, knockout of tubule cell KDM6A has subtle (albeit non-negligible) effects in the adult kidney, at least in males.


Asunto(s)
Histona Demetilasas , Riñón , Enfermedades Ureterales , Animales , Femenino , Masculino , Ratones , Apoptosis , Túbulos Renales , ARN Mensajero/genética , Enfermedades Ureterales/genética , Enfermedades Ureterales/metabolismo
12.
Early Interv Psychiatry ; 15(6): 1686-1695, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-33461243

RESUMEN

AIM: This study aimed to determine the association of biological (BAB) and psychological illness attributional beliefs (PAB) with medication adherence behaviour in patients with psychosis in Hong Kong. METHODS: A cross-sectional survey of 301 outpatients with psychosis in Hong Kong was conducted from August to October 2016. The survey included a set of questionnaires examining patient medication adherence behaviours (using five behavioural items from the Medication Adherence Rating Scale), illness attributional belief, insight into the illness, and attitudes towards antipsychotics and medical professionals. The associations between these variables were analysed using path analysis and adjusted for covariates of perceived social support, experience of side-effects, and gender. RESULTS: The data fit a model in which medication adherence behaviour was associated with illness attributional belief, insight, and attitudes (chi-square = 32.33, p = .26; RMSEA = 0.02; SRMR = 0.04; and CFI = 0.97). BAB was positively and directly associated with medication adherence behaviour. PAB was positively and indirectly associated with medication adherence behaviour through insight into the illness and attitude towards medical professionals. PAB can strengthen the relationship between BAB and insight, and only the high PAB group exhibited a positive relationship between BAB and attitude towards medical professionals. CONCLUSIONS: An integration of biological and psychological attributional beliefs in patients with psychosis is essential for better medication adherence behaviour. Future interventions should aim to modify patients' illness attributional beliefs by integrating both biological and psychological illness attribution to improve medication adherence.


Asunto(s)
Antipsicóticos , Trastornos Psicóticos , Antipsicóticos/uso terapéutico , Estudios Transversales , Conocimientos, Actitudes y Práctica en Salud , Humanos , Cumplimiento de la Medicación/psicología , Trastornos Psicóticos/tratamiento farmacológico , Trastornos Psicóticos/psicología , Encuestas y Cuestionarios
13.
BMJ Open ; 11(7): e047245, 2021 07 09.
Artículo en Inglés | MEDLINE | ID: mdl-34244267

RESUMEN

OBJECTIVES: The Global Kidney Health Atlas (GKHA) is a multinational, cross-sectional survey designed to assess the current capacity for kidney care across all world regions. The 2017 GKHA involved 125 countries and identified significant gaps in oversight, funding and infrastructure to support care for patients with kidney disease, especially in lower-middle-income countries. Here, we report results from the survey for the second iteration of the GKHA conducted in 2018, which included specific questions about health financing and oversight of end-stage kidney disease (ESKD) care worldwide. SETTING: A cross-sectional global survey. PARTICIPANTS: Key stakeholders from 182 countries were invited to participate. Of those, stakeholders from 160 countries participated and were included. PRIMARY OUTCOMES: Primary outcomes included cost of kidney replacement therapy (KRT), funding for dialysis and transplantation, funding for conservative kidney management, extent of universal health coverage, out-of-pocket costs for KRT, within-country variability in ESKD care delivery and oversight systems for ESKD care. Outcomes were determined from a combination of desk research and input from key stakeholders in participating countries. RESULTS: 160 countries (covering 98% of the world's population) responded to the survey. Economic factors were identified as the top barrier to optimal ESKD care in 99 countries (64%). Full public funding for KRT was more common than for conservative kidney management (43% vs 28%). Among countries that provided at least some public coverage for KRT, 75% covered all citizens. Within-country variation in ESKD care delivery was reported in 40% of countries. Oversight of ESKD care was present in all high-income countries but was absent in 13% of low-income, 3% of lower-middle-income, and 10% of upper-middle-income countries. CONCLUSION: Significant gaps and variability exist in the public funding and oversight of ESKD care in many countries, particularly for those in low-income and lower-middle-income countries.


Asunto(s)
Fallo Renal Crónico , Diálisis Renal , Estudios Transversales , Países en Desarrollo , Accesibilidad a los Servicios de Salud , Humanos , Fallo Renal Crónico/terapia
15.
Clin Kidney J ; 11(6): 786-787, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30524712

RESUMEN

Type B lactic acidosis complicating malignancies is rare. Increased lactate production from abnormal metabolism of tumor tissue and extensive liver metastases impairing clearance are usual causes. Fluorouracil, commonly used as adjuvant cancer chemotherapy, is not well recognized among drugs that can lead to lactic acidosis. We report a hemodialysis patient, tumor free after surgery for colon carcinoma, developing acute severe lactic acidosis and encephalopathy. Pharmacogenetic studies failed to show common variants predisposing to the more typical patterns of fluorouracil toxicity. Routine monitoring of hemodialysis patients after fluorouracil is the only practical way to detect this potentially lethal complication.

16.
J Psychopharmacol ; 32(1): 81-88, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-28879800

RESUMEN

Caffeine is a widely used psychostimulant that is associated with increased acetylcholine levels in mammalian brain and acetycholinesterase antagonism. Acetylcholine, a neuromodulator, plays an important role in the processing of visual information. One key example in human vision, thought to at least partly involve cholinergic neuromodulation, is perceptual surround suppression of contrast, whereby the perceived contrast of a pattern is altered by the presence of a neighbouring pattern. Perceptual surround suppression is weaker with pharmacological administration of donepezil (a centrally-acting acetylcholine enzyme inhibitor) in healthy human observers. Here, we test whether temporarily manipulating caffeine levels (from complete washout to a controlled dose of caffeine) has a similar effect on perceptual surround suppression in 21 healthy young adults (aged 20-24 years, 11 females). Neither ingestion of a caffeine pill nor placebo altered contrast judgments when the target pattern was presented on a uniform grey background ( p=0.54). With caffeine ingestion, perceptual surround suppression strength was reduced relative to baseline (prior to pill ingestion, p=0.003) and placebo ( p=0.029), irrespective of whether the surround was oriented parallel or orthogonal to the central target. While daily habitual caffeine consumption of low-to-moderate doses (<400 mg/day, estimated from a written questionnaire) is not predictive of performance, our study indicates that acute consumption of caffeine on the day of testing influences perceptual surround suppression strength. Perceptual surround suppression is predominantly attributed to inhibitory processes involving the major cortical inhibitory neurotransmitter, gamma-aminobutyric acid. Our results point to the involvement of other neuromodulators, possibly cholinergic, in perceptual surround suppression.


Asunto(s)
Cafeína/administración & dosificación , Sensibilidad de Contraste/efectos de los fármacos , Umbral Sensorial/efectos de los fármacos , Percepción Visual/efectos de los fármacos , Adulto , Discriminación en Psicología/efectos de los fármacos , Femenino , Humanos , Masculino , Neurotransmisores/metabolismo , Estimulación Luminosa/métodos , Adulto Joven , Ácido gamma-Aminobutírico/metabolismo
17.
Eur Heart J Cardiovasc Imaging ; 19(3): 347-356, 2018 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-28379401

RESUMEN

Aims: Asymmetric wall thickening has been described in patients with aortic stenosis. However, it remains poorly characterized and its prognostic implications are unclear. We hypothesized this pattern of adaptation is associated with advanced remodelling, left ventricular decompenzation, and a poor prognosis. Methods and results: In a prospective observational cohort study, 166 patients with aortic stenosis (age 69, 69% males, mean aortic valve area 1.0 ± 0.4 cm2) and 37 age and sex-matched healthy volunteers underwent phenotypic characterization with comprehensive clinical, imaging, and biomarker evaluation. Asymmetric wall thickening on both echocardiography and cardiovascular magnetic resonance was defined as regional wall thickening ≥ 13 mm and > 1.5-fold the thickness of the opposing myocardial segment. Although no control subject had asymmetric wall thickening, it was observed in 26% (n = 43) of patients with aortic stenosis using magnetic resonance and 17% (n = 29) using echocardiography. Despite similar demographics, co-morbidities, valve narrowing, myocardial hypertrophy, and fibrosis, patients with asymmetric wall thickening had increased cardiac troponin I and brain natriuretic peptide concentrations (both P < 0.001). Over 28 [22, 33] months of follow-up, asymmetric wall thickening was an independent predictor of aortic valve replacement (AVR) or death whether detected by magnetic resonance [hazard ratio (HR) = 2.15; 95% confidence interval (CI) 1.29-3.59; P = 0.003] or echocardiography (HR = 1.79; 95% CI 1.08-3.69; P = 0.021). Conclusion: Asymmetric wall thickening is common in aortic stenosis and is associated with increased myocardial injury, left ventricular decompenzation, and adverse events. Its presence may help identify patients likely to proceed quickly towards AVR. Clinical Trial Registration: https://clinicaltrials.gov/show/NCT01755936: NCT01755936.


Asunto(s)
Adaptación Fisiológica/fisiología , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Estenosis de la Válvula Aórtica/cirugía , Cardiomegalia/diagnóstico por imagen , Imagen por Resonancia Cinemagnética/métodos , Miocardio/patología , Anciano , Estenosis de la Válvula Aórtica/mortalidad , Estenosis de la Válvula Aórtica/fisiopatología , Cardiomegalia/mortalidad , Cardiomegalia/fisiopatología , Estudios de Casos y Controles , Intervalos de Confianza , Ecocardiografía/métodos , Femenino , Gadolinio , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Valores de Referencia , Medición de Riesgo , Índice de Severidad de la Enfermedad , Tasa de Supervivencia , Reemplazo de la Válvula Aórtica Transcatéter/métodos , Resultado del Tratamiento
18.
JACC Cardiovasc Imaging ; 10(11): 1320-1333, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-28017384

RESUMEN

OBJECTIVES: Cardiac magnetic resonance (CMR) was used to investigate the extracellular compartment and myocardial fibrosis in patients with aortic stenosis, as well as their association with other measures of left ventricular decompensation and mortality. BACKGROUND: Progressive myocardial fibrosis drives the transition from hypertrophy to heart failure in aortic stenosis. Diffuse fibrosis is associated with extracellular volume expansion that is detectable by T1 mapping, whereas late gadolinium enhancement (LGE) detects replacement fibrosis. METHODS: In a prospective observational cohort study, 203 subjects (166 with aortic stenosis [69 years; 69% male]; 37 healthy volunteers [68 years; 65% male]) underwent comprehensive phenotypic characterization with clinical imaging and biomarker evaluation. On CMR, we quantified the total extracellular volume of the myocardium indexed to body surface area (iECV). The iECV upper limit of normal from the control group (22.5 ml/m2) was used to define extracellular compartment expansion. Areas of replacement mid-wall LGE were also identified. All-cause mortality was determined during 2.9 ± 0.8 years of follow up. RESULTS: iECV demonstrated a good correlation with diffuse histological fibrosis on myocardial biopsies (r = 0.87; p < 0.001; n = 11) and was increased in patients with aortic stenosis (23.6 ± 7.2 ml/m2 vs. 16.1 ± 3.2 ml/m2 in control subjects; p < 0.001). iECV was used together with LGE to categorize patients with normal myocardium (iECV <22.5 ml/m2; 51% of patients), extracellular expansion (iECV ≥22.5 ml/m2; 22%), and replacement fibrosis (presence of mid-wall LGE, 27%). There was evidence of increasing hypertrophy, myocardial injury, diastolic dysfunction, and longitudinal systolic dysfunction consistent with progressive left ventricular decompensation (all p < 0.05) across these groups. Moreover, this categorization was of prognostic value with stepwise increases in unadjusted all-cause mortality (8 deaths/1,000 patient-years vs. 36 deaths/1,000 patient-years vs. 71 deaths/1,000 patient-years, respectively; p = 0.009). CONCLUSIONS: CMR detects ventricular decompensation in aortic stenosis through the identification of myocardial extracellular expansion and replacement fibrosis. This holds major promise in tracking myocardial health in valve disease and for optimizing the timing of valve replacement. (The Role of Myocardial Fibrosis in Patients With Aortic Stenosis; NCT01755936).


Asunto(s)
Estenosis de la Válvula Aórtica/complicaciones , Cardiomiopatías/etiología , Insuficiencia Cardíaca/etiología , Hipertrofia Ventricular Izquierda/etiología , Miocardio/patología , Función Ventricular Izquierda , Remodelación Ventricular , Anciano , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Estenosis de la Válvula Aórtica/mortalidad , Estenosis de la Válvula Aórtica/fisiopatología , Biopsia , Cardiomiopatías/diagnóstico por imagen , Cardiomiopatías/mortalidad , Cardiomiopatías/fisiopatología , Estudios de Casos y Controles , Progresión de la Enfermedad , Ecocardiografía , Femenino , Fibrosis , Insuficiencia Cardíaca/diagnóstico por imagen , Insuficiencia Cardíaca/mortalidad , Insuficiencia Cardíaca/fisiopatología , Humanos , Hipertrofia Ventricular Izquierda/diagnóstico por imagen , Hipertrofia Ventricular Izquierda/mortalidad , Hipertrofia Ventricular Izquierda/fisiopatología , Estimación de Kaplan-Meier , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Riesgo , Factores de Tiempo
19.
Health Soc Care Community ; 23(5): 523-31, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25443438

RESUMEN

Stroke is a leading cause of adult disability and community re-integration is a priority for stroke rehabilitation. In North America, we have a growing population of individuals whose first language is not English. Little is known about the experiences of visible minorities living in North America as they re-integrate into the community post stroke or how these experiences change over time. Specifically, this research aimed to explore the experiences and needs of Chinese stroke survivors and family caregivers as they return to community living using the Timing it Right Framework as a conceptual guide. We recruited Cantonese-speaking stroke survivors and family caregivers from outpatient rehabilitation programmes. Using qualitative interviews conducted in Cantonese or English, we examined their experiences and needs as they return to community living and explored the influence of culture and time on their experiences. The interviews were transcribed and translated, and then analysed using framework analysis. Using framework analysis, we coded the data corresponding to the phases of the Timing it Right framework to determine the influence of time on the themes. We interviewed five Cantonese-speaking stroke survivors and 13 caregivers in 2009. We identified two main themes: (i) Participants' education and support needs change over time and (ii) Chinese resources are needed across care environments. These resources include access to care in their preferred language, traditional Chinese medicine, and Chinese food during their recovery and rehabilitation. To optimise Chinese stroke survivors' and caregivers' community re-integration, healthcare professionals should provide timely and accessible education and be aware of the role of Chinese diet and traditional medicine in stroke survivors' rehabilitation.


Asunto(s)
Cuidadores , Vida Independiente , Evaluación de Necesidades , Rehabilitación de Accidente Cerebrovascular , Anciano , Pueblo Asiatico , Canadá , Cuidadores/psicología , China/etnología , Continuidad de la Atención al Paciente , Competencia Cultural , Femenino , Personal de Salud/educación , Humanos , Masculino , Persona de Mediana Edad , Investigación Cualitativa , Apoyo Social
20.
J Ophthalmol ; 2015: 891582, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25810921

RESUMEN

Purpose. The study aims to compare the long-term outcome of conjunctival autograft (CAU) and mitomycin C (MMC) in double-head pterygium surgery. Methods. This is a follow-up study of a comparative interventional trial. Thirty-nine eyes of the 36 patients with double-head pterygium excision in the original study 12 years ago were recruited for clinical assessment. Seven out of the 36 patients were lost. In the original study, each eye with double-head pterygium was randomized to have pterygium excision with CAU on one "head" (temporal or nasal) and MMC on the other "head." All patients were invited for clinical assessment for conjunctival bed status and the presence of pterygium recurrence in the current study. Results. There was no significant difference between the size, morphology, and type of pterygium among the two treatment groups. The recurrence rate of CAU group and MMC group 12 years after excision was 6.3% and 28.1%, respectively (P = 0.020). Among eyes without recurrence, the conjunctival bed was graded higher in the MMC group than the CAU group (P = 0.024). Conclusion. The use of conjunctival autograft has a significantly lower long-term recurrence rate than mitomycin C in double-head pterygium surgery.

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