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1.
Am J Geriatr Psychiatry ; 32(5): 611-621, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38199936

RESUMEN

OBJECTIVE: Eradication of hepatitis C virus (HCV) infection has been linked with improvement in neurocognitive function, but few studies have evaluated the effect of antiviral treatment/ response on risk of dementia. Using data from the Chronic Hepatitis Cohort Study (CHeCS), we investigated how antiviral therapy impacts the risk of developing dementia among patients with HCV. METHODS: A total of 17,485 HCV patients were followed until incidence of dementia, death, or last follow-up. We used an extended landmark modeling approach, which included time-varying covariates and propensity score justification for treatment selection bias, as well as generalized estimating equations (GEE) with a link function as multinominal distribution for a discrete time-to-event data. Death was considered a competing risk. RESULTS: After 15 years of follow-up, 342 patients were diagnosed with incident dementia. Patients who achieved sustained virological response (SVR) had significantly decreased risk of dementia compared to untreated patients, with hazard ratios (HRs) of 0.32 (95% CI 0.22-0.46) among patients who received direct-acting antiviral (DAA) treatment and 0.41 (95% CI 0.26-0.60) for interferon-based (IFN) treatment. Risk reduction remained even when patients failed antiviral treatment (HR 0.38, 95% CI 0.38-0.51). Patients with cirrhosis, Black/African American patients, and those without private insurance were at significantly higher risk of dementia. CONCLUSION: Antiviral treatment independently reduced the risk of dementia among HCV patients, regardless of cirrhosis. Our findings support the importance of initiation antiviral therapy in chronic HCV-infected patients.


Asunto(s)
Demencia , Hepatitis C Crónica , Hepatitis C , Humanos , Antivirales/efectos adversos , Hepacivirus , Estudios de Cohortes , Hepatitis C Crónica/complicaciones , Hepatitis C Crónica/tratamiento farmacológico , Hepatitis C Crónica/epidemiología , Hepatitis C/complicaciones , Hepatitis C/tratamiento farmacológico , Hepatitis C/epidemiología , Cirrosis Hepática/complicaciones , Cirrosis Hepática/tratamiento farmacológico , Demencia/etiología , Demencia/inducido químicamente
2.
J Viral Hepat ; 30(6): 544-550, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36872452

RESUMEN

Research suggests a possible link between chronic infection with hepatitis C virus (HCV) and the development of Parkinson's Disease (PD) and secondary Parkinsonism (PKM). We investigated the impact of antiviral treatment status (untreated, interferon [IFN] treated, direct-acting antiviral [DAA] treated) and outcome (treatment failure [TF] or sustained virological response [SVR]) on risk of PD/PKM among patients with HCV. Using data from the Chronic Hepatitis Cohort Study (CHeCS), we applied a discrete time-to-event approach with PD/PKM as the outcome. We performed univariate followed by a multivariable modelling that used time-varying covariates, propensity scores to adjust for potential treatment selection bias and death as a competing risk. Among 17,199 confirmed HCV patients, we observed 54 incident cases of PD/PKM during a mean follow-up period of 17 years; 3753 patients died during follow-up. There was no significant association between treatment status/outcome and risk of PD/PKM. Type 2 diabetes tripled risk (hazard ratio [HR] 3.05; 95% CI 1.75-5.32; p < .0001) and presence of cirrhosis doubled risk of PD/PKM (HR 2.13, 95% CI 1.31-3.47). BMI >30 was associated with roughly 50% lower risk of PD/PKM than BMI <25 (HR 0.43; 0.22-0.84; p = .0138). After adjustment for treatment selection bias, we did not observe a significant association between HCV patients' antiviral treatment status/outcome on risk of PD/PKM. Several clinical risk factors-diabetes, cirrhosis and BMI-were associated with PD/PKM.


Asunto(s)
Carcinoma Hepatocelular , Diabetes Mellitus Tipo 2 , Hepatitis C Crónica , Hepatitis C , Neoplasias Hepáticas , Enfermedad de Parkinson Secundaria , Enfermedad de Parkinson , Humanos , Antivirales/uso terapéutico , Estudios de Cohortes , Enfermedad de Parkinson/epidemiología , Hepatitis C Crónica/complicaciones , Hepatitis C Crónica/tratamiento farmacológico , Hepatitis C/tratamiento farmacológico , Hepacivirus , Respuesta Virológica Sostenida , Enfermedad de Parkinson Secundaria/inducido químicamente , Enfermedad de Parkinson Secundaria/complicaciones , Enfermedad de Parkinson Secundaria/tratamiento farmacológico , Cirrosis Hepática/complicaciones , Neoplasias Hepáticas/tratamiento farmacológico , Carcinoma Hepatocelular/tratamiento farmacológico
3.
Clin Transplant ; 37(11): e15100, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37577900

RESUMEN

BACKGROUND: Early identification of alcohol use is crucial for informing recommendations of appropriate follow-up treatment pre-liver transplant and optimizing post-liver transplant outcomes. The purpose of the study was to investigate whether there are psychosocial factors associated with a positive PEth test. METHODS: All patients who underwent a routine pre-surgical psychological evaluation for liver transplant listing (all etiologies, including acute liver failure, dual organ, and re-transplantation) at a single health care system in 2020 were included in a retrospective chart review. Data extraction included results from PEth testing and information from the psychological evaluation (i.e., demographic, psychiatric symptoms, and cognitive functioning). RESULTS: There were 158 patients (73.8%) who had a PEth test, of whom 21.5% had a positive result (n = 34). Younger age was associated with a positive PEth (p < .001). ALD status and type of ALD (hepatitis vs. cirrhosis) were also associated with a positive PEth test. Other demographic characteristics and psychiatric symptoms were not associated with a positive PEth result (p > .05). CONCLUSION: Younger age was the only significant demographic variable associated with a positive PEth test. Given the difficulty of predicting who may be using alcohol, it may be useful to use PEth testing for all patients during the pre-liver transplant evaluation and while patients are listed for liver transplant. Early identification of alcohol use through routine PEth testing will help identify patients who are using alcohol and need further treatment for alcohol use to optimize health and post-transplant outcomes.


Asunto(s)
Trasplante de Hígado , Humanos , Estudios Retrospectivos , Glicerofosfolípidos , Cirrosis Hepática , Etanol , Biomarcadores
4.
Liver Int ; 42(4): 762-764, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35094494

RESUMEN

Early reports suggest that alcohol misuse increased in 2020 as a result of the COVID-19 pandemic. Using retrospective data from Henry Ford Health System in Detroit MI-an area that experienced an early and severe COVID-19 outbreak-we investigated the impact of the pandemic on alcohol-related liver disease (ARLD) in the summer of 2020 compared with the same period in 2016-2019. Both the number of ARLD admissions and the proportion of total admissions represented by ARLD patients increased significantly in 2020 compared with previous years. The number of ARLD admissions as a proportion of all hospitalizations was 50% higher in 2020 than in 2016-2019 (0.31% vs 0.21%; P = .0013); by September 2020, the number of admissions was 66% higher than previous years. Despite racial and geographical disparities in direct and indirect COVID-related stressors across the Detroit metropolitan area, the demographic profile of ARLD patients did not change compared with previous years.


Asunto(s)
COVID-19 , Hepatitis Alcohólica , COVID-19/epidemiología , Hepatitis Alcohólica/epidemiología , Hospitalización , Humanos , Pandemias , Estudios Retrospectivos
5.
Clin Transplant ; 36(5): e14595, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35041223

RESUMEN

BACKGROUND: Serum phosphatidylethanol (PEth) is a highly sensitive test to detect alcohol use. We evaluated whether the availability of PEth testing impacted rates of liver transplant evaluation terminations and delistings. METHODS: Medical record data were collected for patients who initiated transplant evaluation due to alcohol-related liver disease in the pre-PEth (2017) or PEth (2019) eras. Inverse probability weighting (IPW) was used to balance baseline patient characteristics. Outcomes included termination of evaluation or delisting due to alcohol use; patients were censored at receipt of transplant; death was considered a competing risk. The Fine-Gray method was performed to determine whether PEth testing affected risk of evaluation termination/ delisting due to alcohol use. RESULTS: Three hundred and seventy-five patients with alcohol-related indications for transplant (157 in 2017; 210 in 2019) were included. The final IPW-adjusted model for the composite outcome of terminations/delisting due to alcohol use retained two significant variables (P < .05): PEth era and BMI category. Patients evaluated during the PEth era were almost three times more likely to experience an alcohol-related termination/delisting than those in the pre-PEth era (sHR = 2.86; 95%CI 1.67-4.97) CONCLUSION: We found that availability of PEth testing at our institution was associated with a higher rate of exclusion of patients from eligibility for liver transplant. Use of PEth testing has significant potential to inform decisions regarding transplant candidacy for patients with alcohol-related liver disease.


Asunto(s)
Hepatopatías , Trasplante de Hígado , Consumo de Bebidas Alcohólicas , Biomarcadores , Humanos
7.
Ann Hepatol ; 22: 100311, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33482365

RESUMEN

INTRODUCTION AND OBJECTIVES: Higher rates of psychiatric disorders are reported among cirrhotic patients. This study examines the demographic and clinical outcomes post-liver transplant (LT) among cirrhotic patients with a major psychiatric diagnosis (cases) compared to those without psychiatric diagnosis (controls). MATERIALS AND METHODS: Retrospective case control design was used among 189 cirrhotic patients who had undergone LT at Methodist University Hospital Transplant Institute, Memphis, TN between January 2006 and December 2014. Multivariable regression and Cox proportional hazard regression were conducted to compare allograft loss and all-cause mortality. RESULTS: The study sample consisted of a matched cohort of 95 cases and 94 controls with LT. Females and those with Hepatic Encephalopathy (HE) were more likely to have psychiatric diagnosis. Patients with hepatocellular carcinoma (HCC) were twice as likely to have allograft loss. Psychiatric patients with HCC had two and a half times (HR 2.54; 95% CI: 1.20-5.37; p = 0.015) likelihood of all-cause mortality. Data censored at 1-year post-LT revealed that patients with psychiatric diagnosis have a three to four times higher hazard for allograft loss and all-cause mortality compared to controls after adjusting for covariates, whereas when the data is censored at 5 year, allograft loss and all-cause mortality have two times higher hazard ratio. CONCLUSIONS: The Cox proportional hazard regression analysis of censored data at 1 and 5 year indicate higher allograft loss and all-cause mortality among LT patients with psychiatric diagnosis. Patients with well-controlled psychiatric disorders who undergo LT need close monitoring and medication adherence.


Asunto(s)
Hepatopatías/psicología , Hepatopatías/cirugía , Trasplante de Hígado , Trastornos Mentales/complicaciones , Adulto , Anciano , Femenino , Supervivencia de Injerto , Humanos , Hepatopatías/mortalidad , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Tasa de Supervivencia , Resultado del Tratamiento
8.
Clin Transplant ; 34(6): e13845, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32096883

RESUMEN

BACKGROUND: Opioid medications are frequently used to address pain among patients with cirrhosis, including those on the liver transplant (LT) waitlist and after transplantation. However, opioid use has been associated with poor allograft outcomes and reduced transplant survival. We examined the impact of opioid use across the spectrum of advanced liver disease, from the initial hepatology consultation for cirrhosis through transplant referral, listing, and the post-LT process. METHODS: The study includes all patients referred for cirrhosis management in a single healthcare system in the United States. Data were extracted retrospectively through medical chart review. RESULTS: Of 414 patients included in the study, 104 (25%) were treated with opioid. Patients on opioids were more likely to be White, have body mass indices (BMI) >30, have HCV, suffer from hepatic encephalopathy, cigarette smokers, and use benzodiazepines concurrently. Higher doses of opioids were associated with multiple emergency department (ED). Eighty-nine underwent LT, including 20 opioid-treated patients. There was no difference found between the opioid and non-opioid groups with regard to allograft loss, ED visits, and hospital readmissions at 2 years post-LT follow-up. CONCLUSIONS: Opioid treatment was common among patients with cirrhosis. We did not find increased negative outcomes among opioid users across the spectrum of cirrhosis. However, the sample for LT patients was small.


Asunto(s)
Analgésicos Opioides , Trasplante de Hígado , Analgésicos Opioides/uso terapéutico , Humanos , Cirrosis Hepática , Estudios Retrospectivos , Estados Unidos/epidemiología , Listas de Espera
9.
J Chem Inf Model ; 60(2): 805-820, 2020 02 24.
Artículo en Inglés | MEDLINE | ID: mdl-31804821

RESUMEN

4-HNE-modified ankyrins have been described in diseases such as diabetes, renal failure, G6PD deficient, sickle cell trait, and P. falciparum infected erythrocytes with different AB0 blood groups. However, effects at the atomic level of this carbonylation on structure and function of modified protein are not yet fully understood. We present a study based on molecular dynamics simulations of nine 4-HNE modified residues of the ZU5-ANK ankyrin domain with ß-spectrin and their binding energy profiles. Results show that 4-HNE induced local conformational changes over all protein systems evaluated, increased mobility in the modification sites, and localized structural changes between the positively charged patch of the ZU5-ANK domain. Carbonylation with 4-HNE on lysine residues decreased the affinity between ZU5-ANK and the 14-ß-spectrin repeat by reducing electrostatic and van der Waals interactions. The presented work provides further insight into understanding the loss of human erythrocyte deformation capacity under conditions of oxidative stress in different diseases.


Asunto(s)
Aldehídos/química , Ancirinas/química , Ancirinas/metabolismo , Simulación de Dinámica Molecular , Espectrina/metabolismo , Eritrocitos/metabolismo , Humanos , Estrés Oxidativo , Unión Proteica , Dominios Proteicos
10.
Liver Transpl ; 25(3): 399-410, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30369023

RESUMEN

Nonalcoholic steatohepatitis (NASH) is one of the top 3 indications for liver transplantation (LT) in Western countries. It is unknown whether renal dysfunction at the time of LT has any effect on post-LT outcomes in recipients with NASH. From the United Network for Organ Sharing-Standard Transplant Analysis and Research data set, we identified 4088 NASH recipients who received deceased donor LT. We divided our recipients a priori into 3 categories: group 1 with estimated glomerular filtration rate (eGFR) <30 mL/minute/1.73 m2 at the time of LT and/or received dialysis within 2 weeks preceding LT (n = 937); group 2 with recipients who had eGFR ≥30 mL/minute/1.73 m2 and who did not receive renal replacement therapy prior to LT (n = 2812); and group 3 with recipients who underwent simultaneous liver-kidney transplantation (n = 339). We examined the association of pretransplant renal dysfunction with death with a functioning graft, all-cause mortality, and graft loss using competing risk regression and Cox proportional hazards models. The mean ± standard deviation age of the cohort at baseline was 58 ± 8 years, 55% were male, 80% were Caucasian, and average exception Model for End-Stage Liver Disease score was 24 ± 9. The median follow-up period was 5 years (median, 1816 days; interquartile range, 1090-2723 days). Compared with group 1 recipients, group 2 recipients had 19% reduced trend for risk for death with a functioning graft (subhazard ratio [SHR], 0.81; 95% confidence interval [CI], 0.64-1.02) and similar risk for graft loss (SHR, 1.25; 95% CI, 0.59-2.62), whereas group 3 recipients had similar risk for death with a functioning graft (SHR, 1.23; 95% CI, 0.96-1.57) and graft loss (SHR, 0.18; 95% CI, 0.02-1.37) using an adjusted competing risk regression model. In conclusion, recipients with preserved renal function before LT showed a trend toward lower risk of death with a functioning graft compared with SLKT recipients and those with pretransplant severe renal dysfunction in patients with NASH.


Asunto(s)
Supervivencia de Injerto , Fallo Renal Crónico/fisiopatología , Trasplante de Riñón/efectos adversos , Riñón/fisiopatología , Trasplante de Hígado/efectos adversos , Enfermedad del Hígado Graso no Alcohólico/cirugía , Anciano , Conjuntos de Datos como Asunto , Femenino , Estudios de Seguimiento , Tasa de Filtración Glomerular/fisiología , Humanos , Riñón/cirugía , Fallo Renal Crónico/etiología , Fallo Renal Crónico/mortalidad , Fallo Renal Crónico/terapia , Masculino , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Enfermedad del Hígado Graso no Alcohólico/mortalidad , Enfermedad del Hígado Graso no Alcohólico/fisiopatología , Periodo Preoperatorio , Diálisis Renal/estadística & datos numéricos , Medición de Riesgo , Factores de Riesgo , Análisis de Supervivencia , Resultado del Tratamiento , Estados Unidos/epidemiología
11.
PLoS Comput Biol ; 14(4): e1006082, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29659564

RESUMEN

In this work, we assess a previously advanced hypothesis that predicts the existence of ion channels in the capsid of small and non-enveloped icosahedral viruses. With this purpose we examine Triatoma Virus (TrV) as a case study. This virus has a stable capsid under highly acidic conditions but disassembles and releases the genome in alkaline environments. Our calculations range from a subtle sub-atomic proton interchange to the dismantling of a large-scale system representing several million of atoms. Our results provide structure-based explanations for the three roles played by the capsid to enable genome release. First, we observe, for the first time, the formation of a hydrophobic gate in the cavity along the five-fold axis of the wild-type virus capsid, which can be disrupted by an ion located in the pore. Second, the channel enables protons to permeate the capsid through a unidirectional Grotthuss-like mechanism, which is the most likely process through which the capsid senses pH. Finally, assuming that the proton leak promotes a charge imbalance in the interior of the capsid, we model an internal pressure that forces shell cracking using coarse-grained simulations. Although qualitatively, this last step could represent the mechanism of capsid opening that allows RNA release. All of our calculations are in agreement with current experimental data obtained using TrV and describe a cascade of events that could explain the destabilization and disassembly of similar icosahedral viruses.


Asunto(s)
Dicistroviridae/fisiología , Dicistroviridae/ultraestructura , Canales Iónicos/metabolismo , Animales , Cápside/fisiología , Cápside/ultraestructura , Biología Computacional , Dicistroviridae/genética , Concentración de Iones de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Modelos Biológicos , Modelos Moleculares , Simulación de Dinámica Molecular , Protones , Electricidad Estática , Ensamble de Virus/fisiología
12.
Clin Gastroenterol Hepatol ; 16(6): 965-973.e2, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29427734

RESUMEN

BACKGROUND & AIMS: Data on the differences in ethnicity and race among patients with primary biliary cholangitis (PBC) awaiting liver transplantation (LT) are limited. We evaluated liver transplant waitlist trends and outcomes based on ethnicity and race in patients with PBC in the United States. METHODS: Using the United Network for Organ Sharing (UNOS) registry, we collected data on patients with PBC on the liver transplant waitlist, and performed analysis with a focus on ethnicity and race-based variations clinical manifestations, waitlist mortality and LT rates from 2000 to 2014. Outcomes were adjusted for demographics, complications of portal hypertension, and Model for End-stage Liver Disease score at time of waitlist registration. RESULTS: Although the number of white PBC waitlist registrants and additions decreased from 2000 to 2014, there were no significant changes in the number of Hispanic PBC waitlist registrants and additions each year. The proportion of Hispanic patients with PBC on the liver transplant waitlist increased from 10.7% in 2000 to 19.3% in 2014. Hispanics had the highest percentage of waitlist deaths (20.8%) of any ethnicity or race evaluated. After adjusting for demographic and clinical characteristics, Hispanic patients with PBC had the lowest overall rate for undergoing LT (adjusted hazard ratio, 0.71; 95% CI, 0. 60-0.83; P < .001) and a significantly higher risk of death while on the waitlist, compared to whites (adjusted hazard ratio, 1.41; 95% CI, 1.15-1.74; P < .001). Furthermore, Hispanic patients with PBC had the highest proportion of waitlist removals due to clinical deterioration. CONCLUSIONS: In an analysis of data from UNOS registry focusing on outcomes, we observed differences in rates of LT and liver transplant waitlist mortality of Hispanic patients compared with white patients with PBC. Further studies are needed to improve our understanding of ethnicity and race-based differences in progression of PBC.


Asunto(s)
Cirrosis Hepática Biliar/mortalidad , Cirrosis Hepática Biliar/terapia , Trasplante de Hígado/estadística & datos numéricos , Utilización de Procedimientos y Técnicas/estadística & datos numéricos , Listas de Espera , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Hispánicos o Latinos , Humanos , Masculino , Persona de Mediana Edad , Factores Raciales , Estudios Retrospectivos , Estados Unidos , Adulto Joven
14.
Liver Transpl ; 24(8): 1040-1049, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29573131

RESUMEN

The effect of antiviral therapy (AVT) on kidney function in liver transplantation (LT) recipients has not been well described despite known association of hepatitis C virus (HCV) infection with chronic kidney disease (CKD). We compared the incidence of CKD and end-stage renal disease (ESRD) in 204 LT recipients with HCV based on treatment response to AVT. The mean estimated glomerular filtration rate (eGFR) at baseline (3 months after LT) was similar in the sustained virological response (SVR; n = 145) and non-SVR group (n = 59; 69 ± 21 versus 65 ± 33 mL/minute/1.73 m2 ; P = 0.27). In the unadjusted Cox proportional regression analysis, the presence of SVR was associated with an 88% lower risk of CKD (hazard ratio, 0.12; 95% confidence interval [CI], 0.05-0.31) and 86% lower risk of ESRD (odds ratio, 0.14; 95% CI, 0.05-0.35). Similar results were found after adjusting for propensity score and time-dependent Cox regression analyses. The estimated slopes of eGFR based on a 2-stage mixed model of eGFR were calculated. Patients with SVR had a less steep slope in eGFR (-0.60 mL/minute/1.73 m2 /year; 95% CI, -1.50 to 0.30; P = 0.190) than recipients without SVR (-2.53 mL/minute/1.73 m2 /year; 95% CI, -3.99 to -1.07; P = 0.001), and the differences in the slopes were statistically significant (P = 0.026). In conclusion, in LT recipients with chronic HCV infection, achieving SVR significantly lowers the risk of decline in renal function and progression to ESRD independent of the AVT therapy used.


Asunto(s)
Antivirales/uso terapéutico , Hepatitis C Crónica/tratamiento farmacológico , Fallo Renal Crónico/epidemiología , Cirrosis Hepática/cirugía , Trasplante de Hígado/efectos adversos , Complicaciones Posoperatorias/epidemiología , Progresión de la Enfermedad , Quimioterapia Combinada/métodos , Femenino , Tasa de Filtración Glomerular , Hepacivirus/aislamiento & purificación , Hepatitis C Crónica/complicaciones , Hepatitis C Crónica/patología , Hepatitis C Crónica/virología , Humanos , Incidencia , Riñón/fisiopatología , Fallo Renal Crónico/diagnóstico , Fallo Renal Crónico/etiología , Fallo Renal Crónico/fisiopatología , Cirrosis Hepática/complicaciones , Cirrosis Hepática/patología , Cirrosis Hepática/virología , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/fisiopatología , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Respuesta Virológica Sostenida
15.
Opt Express ; 26(16): 20342-20350, 2018 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-30119345

RESUMEN

A single-pixel digital holography system with phase-encoded illumination using a digital micromirror device (DMD) as a spatial light modulator (SLM) is presented. The enhanced switching rate of DMDs, far exceeding the stringent frame-rate of liquid crystal SLMs, allows recording and reconstruction of complex amplitude distributions in just a few seconds. A single amplitude binary modulation device is used for concurrently displaying the phase-encoded sampling patterns, compensating the distortion of the wavefront, and applying phase-shifting, by means of computer generated holograms. Our detection system consists of a simple photodiode that sequentially records the irradiance fluctuations corresponding to the interference between object and reference beams. The system recovers phase and amplitude information even when a diffuser is placed in front of the photodiode.

18.
Pharmacol Res ; 121: 194-201, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28495657

RESUMEN

Meningococcal disease is caused mainly by serogroups A, B, C, Y, W of N. meningitidis. However, numerous cases of meningitis caused by serogroup X N. meningitidis (MenX) have recently been reported in several African countries. Currently, there are no licensed vaccines against this pathogen and most of the MenX cases have been caused by meningococci from clonal complex (c.c) 181. Detergent extracted meningococcal outer membrane vesicle (dOMV) vaccines have previously shown to be safe and effective against epidemics of serogroup B meningococcal disease in all age groups. The aim of this work is therefore to obtain, characterize and evaluate the vaccine potential of dOMVs derived from a MenX strain (OMVx). Three experimental lots of OMVx were prepared by deoxycholate extraction from the MenX strain BF 2/97. Size and morphology of the vesicles was determined by Dynamic Light Scattering and electron microscopy, whereas the antigenic composition was characterized by gel electrophoresis and immunoblotting. OMVx were thereafter adsorbed to aluminium hydroxide (OMVx/AL) and two doses of OMVx were administered s.c. to groups of Balb/c mice three weeks apart. The immunogenicity and functional antibody activities in sera were evaluated by ELISA (anti-OMVx specific IgG responses) and serum bactericidal activity (SBA) assay. The size range of OMVx was shown to be between 90 and 120nm, whereas some of the antigens detected were the outer membrane proteins PorA, OpcA and RmpM. The OMVx/AL elicited high anti-OMVx antibody responses with bactericidal activity and no bactericidal activity was observed in the control group of no immunised mice. The results demonstrate that OMVx are immunogenic and could form part of a future vaccine to prevent the majority of meningococcal disease in the African meningitis belt.


Asunto(s)
Proteínas de la Membrana Bacteriana Externa/uso terapéutico , Infecciones Meningocócicas/prevención & control , Vacunas Meningococicas/uso terapéutico , Neisseria meningitidis/inmunología , África/epidemiología , Animales , Formación de Anticuerpos , Proteínas de la Membrana Bacteriana Externa/inmunología , Proteínas de la Membrana Bacteriana Externa/aislamiento & purificación , Femenino , Humanos , Inmunización , Infecciones Meningocócicas/epidemiología , Infecciones Meningocócicas/inmunología , Vacunas Meningococicas/inmunología , Vacunas Meningococicas/aislamiento & purificación , Ratones Endogámicos BALB C
19.
Ecotoxicol Environ Saf ; 139: 481-487, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28214645

RESUMEN

The use of antibiotics in agriculture produces residues in wastewaters. The disposal of such wastewaters in biopurification systems (BPS) employed for the treatment of pesticides could result in the inhibition of the degrading capacity of the biomixtures used in the BPS. We assayed the effect of two commercial formulations of antibiotics used in agriculture, one containing kasugamycin (KSG) and the other oxytetracycline plus gentamicin (OTC+GTM), on the biomixture performance. Doses from 0.1mgkg-1 to 1000mgkg-1 of KSG increased the respiration of the biomixture, and low doses enhanced the mineralization rate of the insecticide 14C-chlorpyrifos. On the contrary, OTC+GTM depressed the respiration of the biomixture and the initial mineralization rate of 14C-chlorpyrifos; nonetheless, the antibiotics did not decrease overall mineralization values. The application of both formulations in the biomixture at a relevant concentration did not harm the removal of the fungicides carbendazim and metalaxyl, or their enhanced degradation; on the other hand, the biomixture was unable to dissipate tebuconazol or triadimenol, a result that was unchanged during the addition of the antibiotic formulations. These findings reveal that wastewater containing these antibiotics do not affect the performance of BPS. However, such a response may vary depending on the type of pesticide and microbial consortium in the biomixture.


Asunto(s)
Antibacterianos/farmacología , Cloropirifos/metabolismo , Fungicidas Industriales/metabolismo , Insecticidas/metabolismo , Aguas Residuales , Contaminantes Químicos del Agua/metabolismo , Purificación del Agua , Agricultura , Alanina/análogos & derivados , Alanina/metabolismo , Bencimidazoles/metabolismo , Carbamatos/metabolismo , Consorcios Microbianos
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