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We measure stock market efficiency by drawing the comprehensive sample from Asia, Europe, Africa, North-South America, and Pacific Ocean regions and rank the cross-regional stock markets according to their level of informational efficiency. The study period spans from January 1, 1994, to August 3, 2017. We employ the approximate entropy approach and find that stock market efficiency evolves over the period. The degree and nature of evolution vary across regions and the development stage of the markets. The global, regional, domestic economic, and non-economic factors influence the adaptive nature of the stock markets. The emerging stock markets have improved efficiency by financial liberalization policy but are adversely affected by global shocks. The estimates validate the relevance of the adaptive market framework to describe the rejection of random walk without excess returns. The results suggest the growing presence of technical analysis and active portfolio managers. The emerging markets in Asia hold policy lessons for their peers. The findings suggest that global investors need to overcome the homogeneity bias as returns opportunities exist within the region and types of markets.
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We examine a theoretically robust but previously undocumented issue of what drives foreign portfolio investments into emerging markets. Foreign institutional investors (FIIs) are often blamed as fair-weather friends who pull out their investment at the first sign of trouble. Using a bottom-up approach, we explore this possibility. We demonstrate the influence of the firm-specific factors such as size, book to market ratio, the riskiness of the stocks, stock prices, dividend yield, liquidity, leverage, and earnings on the FII ownership. We find no evidence to show foreign investors as fair-weather friends. Instead, they are smart traders who follow a diligent investment strategy. We suggest reforms in corporate governance and improvement in financial fundamentals of the companies to attract FII ownership. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s40953-021-00233-3.
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ABSTRACT: This study addresses the question of whether the adaptive market hypothesis provides a better description of the behaviour of emerging stock market like India. We employed linear and nonlinear methods to evaluate the hypothesis empirically. The linear tests show a cyclical pattern in linear dependence suggesting that the Indian stock market switched between periods of efficiency and inefficiency. In contrast, the results from nonlinear tests reveal a strong evidence of nonlinearity in returns throughout the sample period with a sign of tapering magnitude of nonlinear dependence in the recent period. The findings suggest that Indian stock market is moving towards efficiency. The results provide additional insights on association between financial crises, foreign portfolio investments and inefficiency. JEL CODES: G14; G12; C12.
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Lesión Renal Aguda/patología , Trasplante de Riñón/efectos adversos , Donantes de Tejidos , Obtención de Tejidos y Órganos , Lesión Renal Aguda/cirugía , Adulto , Anciano , Biopsia con Aguja , Muerte Encefálica , Educación Médica Continua , Estudios de Seguimiento , Supervivencia de Injerto , Humanos , Inmunohistoquímica , Pruebas de Función Renal , Trasplante de Riñón/métodos , Masculino , Complicaciones Posoperatorias/patología , Complicaciones Posoperatorias/terapia , Cuidados Preoperatorios/métodos , Recuperación de la Función , Diálisis Renal/métodos , Medición de Riesgo , Trasplante Homólogo , Resultado del TratamientoRESUMEN
Legionella species are intracellular gram-negative bacilli that require specific culture media for growth. Transplant recipients with impaired cellular immunity are at particular risk for infection with this pathogen. Most human disease is caused by Legionella pneumophila; disease caused by non-L. pneumophila species is reported mainly in immunosuppressed patients with the exception of Legionella longbeachae. L. longbeachae is a common cause of Legionnaires' disease in Australia and New Zealand, and is associated with exposure to potting soil. We report the case of a patient, 26 years post kidney transplant, who presented with severe and rapidly progressive respiratory illness. L. longbeachae serogroup 1 was isolated from respiratory cultures. Further investigation revealed that she had significant soil exposure before the onset of illness. We highlight the importance of following safe living strategies to prevent exposure-related illness even in long-term transplant recipients.
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Exposición a Riesgos Ambientales , Trasplante de Riñón/efectos adversos , Legionella longbeachae/aislamiento & purificación , Enfermedad de los Legionarios/microbiología , Sistema Respiratorio/microbiología , Femenino , Humanos , Enfermedad de los Legionarios/diagnóstico , Enfermedad de los Legionarios/fisiopatología , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Microbiología del Suelo , Factores de TiempoRESUMEN
The Banff scoring schema provides a common ground to analyze kidney transplant biopsies. Interstitial inflammation (i) and tubulitis (t) in areas of viable tissue are features in scoring acute rejection, but are excluded in areas of tubular atrophy (TA). We studied inflammation and tubulitis in a cohort of kidney transplant recipients undergoing allograft biopsy for new-onset late graft dysfunction (N = 337). We found inflammation ('iatr') and tubulitis ('tatr') in regions of fibrosis and atrophy to be strongly correlated with each other (p < 0.0001). Moreover, iatr was strongly associated with death-censored graft failure when compared to recipients whose biopsies had no inflammation, even after adjusting for the presence of interstitial fibrosis (Hazard Ratio = 2.31, [1.10-4.83]; p = 0.0262) or TA (hazard ratio = 2.42, [1.16-5.08]; p = 0.191), serum creatinine at the time of biopsy, time to biopsy and i score. Further, these results did not qualitatively change after additional adjustments for C4d staining or donor specific antibody. Stepwise regression identified the most significant markers of graft failure which include iatr score. We propose that a more global assessment of inflammation in kidney allograft biopsies to include inflammation in atrophic areas may provide better prognostic information. Phenotypic characterization of these inflammatory cells and appropriate treatment may ameliorate late allograft failure.
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Trasplante de Riñón/patología , Túbulos Renales/patología , Nefritis/patología , Atrofia , Biopsia , Estudios de Cohortes , Creatinina/sangre , Estudios Transversales , Femenino , Fibrosis , Rechazo de Injerto/mortalidad , Humanos , Técnicas In Vitro , Masculino , Nefritis/sangre , Valor Predictivo de las Pruebas , Modelos de Riesgos Proporcionales , Medición de Riesgo , Índice de Severidad de la Enfermedad , Trasplante HomólogoRESUMEN
We are studying two cohorts of kidney transplant recipients, with the goal of defining specific clinicopathologic entities that cause late graft dysfunction: (1) prevalent patients with new onset late graft dysfunction (cross-sectional cohort); and (2) newly transplanted patients (prospective cohort). For the cross-sectional cohort (n = 440), mean time from transplant to biopsy was 7.5 +/- 6.1 years. Local pathology diagnoses included CAN (48%), CNI toxicity (30%), and perhaps surprisingly, acute rejection (cellular- or Ab-mediated) (23%). Actuarial rate of death-censored graft loss at 1 year postbiopsy was 17.7%; at 2 years, 29.8%. There was no difference in postbiopsy graft survival for recipients with versus without CAN (p = 0.9). Prospective cohort patients (n = 2427) developing graft dysfunction >3 months posttransplant undergo 'index' biopsy. The rate of index biopsy was 8.8% between 3 and 12 months, and 18.2% by 2 years. Mean time from transplant to index biopsy was 1.0 +/- 0.6 years. Local pathology diagnoses included CAN (27%), and acute rejection (39%). Intervention to halt late graft deterioration cannot be developed in the absence of meaningful diagnostic entities. We found CAN in late posttransplant biopsies to be of no prognostic value. The DeKAF study will provide broadly applicable diagnostic information to serve as the basis for future trials.
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Supervivencia de Injerto/inmunología , Biopsia , Humanos , PronósticoRESUMEN
The nonspecific diagnoses 'chronic rejection''CAN', or 'IF/TA' suggest neither identifiable pathophysiologic mechanisms nor possible treatments. As a first step to developing a more useful taxonomy for causes of new-onset late kidney allograft dysfunction, we used cluster analysis of individual Banff score components to define subgroups. In this multicenter study, eligibility included being transplanted prior to October 1, 2005, having a 'baseline' serum creatinine < or =2.0 mg/dL before January 1, 2006, and subsequently developing deterioration of graft function leading to a biopsy. Mean time from transplant to biopsy was 7.5 +/- 6.1 years. Of the 265 biopsies (all with blinded central pathology interpretation), 240 grouped into six large (n > 13) clusters. There were no major differences between clusters in recipient demographics. The actuarial postbiopsy graft survival varied by cluster (p = 0.002). CAN and CNI toxicity were common diagnoses in each cluster (and did not differentiate clusters). Similarly, C4d and presence of donor specific antibody were frequently observed across clusters. We conclude that for recipients with new-onset late graft dysfunction, cluster analysis of Banff scores distinguishes meaningful subgroups with differing outcomes.
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Análisis por Conglomerados , Creatinina , Biopsia , Complemento C4b , Creatinina/sangre , Supervivencia de Injerto , Humanos , Fragmentos de Péptidos , Insuficiencia Renal/diagnóstico , Insuficiencia Renal/patología , Donantes de Tejidos , Resultado del TratamientoRESUMEN
Death with function causes half of late kidney transplant failures, and cardiovascular disease (CVD) is the most common cause of death in these patients. We examined the use of potentially cardioprotective medications in a prospective observational study at seven transplant centers in the United States and Canada. Among 935 patients, 87% received antihypertensive medications at both 1 and 6 months after transplantation. Similar antihypertensive regimens were used for patients with and without diabetes and CVD, but with wide variability among centers. In contrast, while 44% of patients were on angiotensin converting enzyme inhibitors (ACEI) or angiotensin receptor blockers (ARB) at the time of transplantation, the proportion taking these agents dropped to 12% at month 1, then increased to 24% at 6 months. Fewer than 30% with CVD or diabetes received ACEI/ARB therapy 6 months posttransplant. Aspirin use was uncommon (<40% of patients). Even among those with diabetes and/or CVD, fewer than 60% received aspirin and only half received a statin at 1 and 6 months. This study demonstrates marked variability in the use of cardioprotective medications in kidney transplant recipients, a finding that may reflect, among several possible explanations, clinical uncertainty due the lack of randomized trials for these medications in this population.
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Cardiotónicos/uso terapéutico , Enfermedades Cardiovasculares/etiología , Enfermedades Cardiovasculares/prevención & control , Trasplante de Riñón/efectos adversos , Adulto , Bloqueadores del Receptor Tipo 1 de Angiotensina II/uso terapéutico , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Antihipertensivos/uso terapéutico , Aspirina/uso terapéutico , Canadá , Estudios de Cohortes , Estudios Transversales , Femenino , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Estados UnidosRESUMEN
We report the case of a 54-year-old woman who underwent living-related renal transplantation for end-stage renal disease from IgA nephropathy. She was subsequently diagnosed with antibody-mediated rejection (AMR) and received rituximab, a potent B-cell suppressive agent. After therapy with rituximab, she developed Pneumocystis jirovecii pneumonia (PJP) requiring hospitalization. We discuss the increasing literature for the use of rituximab for AMR and the need for PJP prophylaxis in this setting.
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Anticuerpos Monoclonales/efectos adversos , Factores Inmunológicos/efectos adversos , Trasplante de Riñón/efectos adversos , Pneumocystis carinii , Neumonía por Pneumocystis/etiología , Complicaciones Posoperatorias/microbiología , Antiinfecciosos/uso terapéutico , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Monoclonales de Origen Murino , Atovacuona/uso terapéutico , Femenino , Rechazo de Injerto/prevención & control , Humanos , Factores Inmunológicos/uso terapéutico , Inyecciones Intravenosas , Persona de Mediana Edad , Neumonía por Pneumocystis/diagnóstico por imagen , Complicaciones Posoperatorias/diagnóstico por imagen , Radiografía , Rituximab , Tomógrafos Computarizados por Rayos X , Resultado del Tratamiento , Trimetoprim/uso terapéuticoRESUMEN
Kidney failure is relatively common among Canadians of Asian origin. However, little is known about the health outcomes after initiation of renal replacement therapy in this population. Our study evaluates differences in the likelihood of renal transplantation and graft loss among Asian and white patients. We studied 21 523 adults of East Asian, Indo Asian or white ethnicity who had initiated dialysis in Canada from 1990-2000. Subjects were followed until death, loss to follow-up or end of study (2004). The proportion of the eligible subjects who were East Asian, Indo Asian, or white was 6, 3, and 91%, respectively. Compared to white patients, East Asian and Indo Asian patients were significantly less likely to receive a renal transplant after adjusting for potential confounding factors. This disparity is greater for transplants from living donors as compared to those from deceased donors. The adjusted death censored graft loss in transplant recipients was not significantly different between ethnic groups. The adjusted risk of death following transplantation, however, was significantly lower in Indo Asian than in white patients. Our findings show that in a Canadian population, patients of East Asian or Indo Asian origin had lower rates of renal transplantation than white patients, especially for living donor transplantation. These findings warrant further study, especially given the good graft outcomes in these individuals.
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Pueblo Asiatico/estadística & datos numéricos , Supervivencia de Injerto , Accesibilidad a los Servicios de Salud/estadística & datos numéricos , Fallo Renal Crónico/etnología , Fallo Renal Crónico/terapia , Trasplante de Riñón/mortalidad , Diálisis Renal/mortalidad , Población Blanca/estadística & datos numéricos , Anciano , Canadá/epidemiología , Asia Oriental/etnología , Femenino , Estudios de Seguimiento , Humanos , India/etnología , Fallo Renal Crónico/mortalidad , Fallo Renal Crónico/cirugía , Donadores Vivos/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Sistema de Registros/estadística & datos numéricos , Medición de Riesgo , Factores de Tiempo , Trasplante Homólogo/estadística & datos numéricos , Resultado del TratamientoRESUMEN
Full publication of abstracts presented at scientific meetings ranges from 25-74%. To determine the rate and factors associated with publication in organ transplantation, we examined abstracts presented at the American Transplant Congress in May 2000. Of 1147 abstracts, 607 (53%) achieved full publication at 4.5 years (mean 1.32 +/- 0.88 years). Fifty-nine percent (357/607) were published in three transplantation journals. For randomized trials, the proportion published was 61%. On multivariate analysis, industry sponsorship (OR 1.78; 95% CI 1.04-3.06), basic science research (OR 1.68; 95% CI 1.32-2.14), non-American center (OR 1.67; 95% CI 1.28-2.20) and oral presentation (OR 1.36; 95% CI 1.07-1.73) were independent predictors of full publication. Nearly half of all abstracts presented at a transplantation meeting remain unpublished. This finding needs to be considered when interpreting systematic reviews in the field of transplantation.
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Congresos como Asunto , Trasplante de Órganos , Publicaciones Periódicas como Asunto/normas , HumanosRESUMEN
UNLABELLED: Modified release (MR) tacrolimus is an extended release formulation administered once daily (qD). The purpose of this pharmacokinetic (PK) study was to evaluate tacrolimus exposure in stable kidney transplant recipients converted from Prograf twice a day to MR tacrolimus qD. METHODS: This was an open-label, multicenter study with a crossover design. Eligible patients were 18 to 65 years of age, more than 6 months posttransplant with stable renal function, and received stable Prograf doses more than 2 weeks prior to enrollment. Patients received Prograf twice a day through day 7; 24-hour PK profiles were obtained on days 1 and 7. Patients were converted to the same milligram-for-milligram daily dose of MR tacrolimus qD in the morning on day 8; 24-hour PK profiles were obtained for MR tacrolimus on days 8, 14, and 21. Laboratory and safety parameters were also evaluated. RESULTS: Most patients (67 of 70) completed all 5 PK profiles. The 90% confidence intervals (CI) for the MR tacrolimus vs Prograf comparison at steady state (days 14 and 21 vs days 1 and 7) were 90.7 and 99.4 for AUC0-24 and 82.7 and 91.9 for Cmin. MR tacrolimus was well tolerated with a safety profile comparable to that of Prograf. AUC0-24 was highly correlated to Cmin for Prograf (day 1, r = 0.80; day 7, r = 0.84) and MR tacrolimus (day 14, r = 0.92; day 21, r = 0.86). Renal function remained stable after conversion to MR tacrolimus. CONCLUSION: The steady state PK of MR tacrolimus are equivalent to Prograf after a milligram-for-milligram conversion in stable kidney transplant recipients. The results provide evidence to support a safe 1:1 conversion from Prograf twice a day to MR tacrolimus.
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Trasplante de Riñón/inmunología , Tacrolimus/administración & dosificación , Tacrolimus/farmacocinética , Adulto , Anciano , Área Bajo la Curva , Estudios Cruzados , Preparaciones de Acción Retardada , Esquema de Medicación , Quimioterapia Combinada , Humanos , Inmunosupresores/administración & dosificación , Inmunosupresores/farmacocinética , Inmunosupresores/uso terapéutico , Tasa de Depuración Metabólica , Persona de Mediana Edad , Tacrolimus/uso terapéuticoRESUMEN
BACKGROUND: Organ transplantation is the preferred treatment for end-stage renal disease. Renal transplant recipients are surviving longer with a better quality of life. Although many hospitals have transplant education programs in place, transplant patients indicate that there is a need for additional information. Transplant Friends is a program designed to meet these needs. PATIENTS AND METHODS: At the University of Alberta, 128 patients attended the Transplant Friends program between September 2002 and February 2003. Each patient completed an evaluation form consisting of 15 questions designed to evaluate patient's satisfaction regarding session content, ease of scheduling, and the sessions facilitators. Responses were recorded using 5-point Likert scales. RESULTS: All 128 participants completed the questionnaires. The predominantly male (59.1%) and Caucasian (91.6%) population had a median age of 49.1 years. Of the 128 patients, 110 patients (86%) felt that the content of the program met or exceeded their expectations; 120 patients (94%) felt the program facilitators met or exceeded their expectations; and 113 patients (88%) evaluated the scheduling favorably. CONCLUSION: Patients require complete information prior to renal transplantation to make an informed decision about whether to proceed with transplant as well as to enhance the overall transplant experience. Patients evaluated the Transplant Friends program as successfully meeting these needs through a comprehensive interactive teaching program. We recommend that institutions performing renal transplants incorporate an educational program such as Transplant Friends during the workup process of this unique patient population.
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Trasplante de Riñón/rehabilitación , Educación del Paciente como Asunto , Alberta , Etnicidad , Femenino , Humanos , Consentimiento Informado , Fallo Renal Crónico/cirugía , Masculino , Persona de Mediana Edad , Satisfacción del Paciente , Encuestas y Cuestionarios , Listas de EsperaAsunto(s)
Aciclovir/uso terapéutico , Infecciones por Citomegalovirus/prevención & control , Ganciclovir/uso terapéutico , Inmunosupresores/uso terapéutico , Trasplante de Órganos , Adolescente , Adulto , Anciano , Humanos , Persona de Mediana Edad , Ensayos Clínicos Controlados Aleatorios como AsuntoRESUMEN
We postulated that as a hibernating species, frogs might have variable demands for nutrients at different seasons of the year and that this must be reflected in seasonal variations of physiologic processes related to nutrient transport and absorption. We examined the rate of mucus transport on the ciliated palate and the movement of nutrients across the intestinal lumen of leopard frogs, Rana pipiens. Mucus transport on the frog palate was strongly influenced by season, with maximal transport occurring in late June (Julian day 178, p = 0.0001; r = 0.58). This increased transport rate was associated with a summertime increase in mucus recoil (lower tangent delta) and a decrease in mucus hydration (increase in percent solids composition). Intestinal transport of leucine, lysine, and galactose did not appear to exhibit seasonal variability. These data suggest that different mechanisms may operate in determining seasonal variability in physiologic responses.