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1.
PLoS Pathog ; 17(2): e1009270, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33600478

RESUMEN

Nosemosis C, a Nosema disease caused by microsporidia parasite Nosema ceranae, is a significant disease burden of the European honey bee Apis mellifera which is one of the most economically important insect pollinators. Nevertheless, there is no effective treatment currently available for Nosema disease and the disease mechanisms underlying the pathological effects of N. ceranae infection in honey bees are poorly understood. Iron is an essential nutrient for growth and survival of hosts and pathogens alike. The iron tug-of-war between host and pathogen is a central battlefield at the host-pathogen interface which determines the outcome of an infection, however, has not been explored in honey bees. To fill the gap, we conducted a study to investigate the impact of N. ceranae infection on iron homeostasis in honey bees. The expression of transferrin, an iron binding and transporting protein that is one of the key players of iron homeostasis, in response to N. ceranae infection was analysed. Furthermore, the functional roles of transferrin in iron homeostasis and honey bee host immunity were characterized using an RNA interference (RNAi)-based method. The results showed that N. ceranae infection causes iron deficiency and upregulation of the A. mellifera transferrin (AmTsf) mRNA in honey bees, implying that higher expression of AmTsf allows N. ceranae to scavenge more iron from the host for its proliferation and survival. The suppressed expression levels of AmTsf via RNAi could lead to reduced N. ceranae transcription activity, alleviated iron loss, enhanced immunity, and improved survival of the infected bees. The intriguing multifunctionality of transferrin illustrated in this study is a significant contribution to the existing body of literature concerning iron homeostasis in insects. The uncovered functional role of transferrin on iron homeostasis, pathogen growth and honey bee's ability to mount immune responses may hold the key for the development of novel strategies to treat or prevent diseases in honey bees.


Asunto(s)
Abejas/microbiología , Interacciones Huésped-Patógeno , Hierro/metabolismo , Microsporidiosis/prevención & control , Nosema/fisiología , Transferrinas/metabolismo , Animales , Microsporidiosis/inmunología , Microsporidiosis/metabolismo , Microsporidiosis/microbiología , Transferrinas/genética
2.
Clin Transplant ; 37(1): e14834, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36259510

RESUMEN

BACKGROUND: In the United Network of Organ Sharing (UNOS) allocation scheme prior to October 18, 2018, heart transplant (HTx) candidates with extracorporeal membrane oxygenation (ECMO), temporary mechanical circulatory support (MCS), or pulmonary artery (PA) catheter inotropic support all received Status 1A priority. In revised scheme, patients with PA catheter and inotropic support are Status 3 after those on ECMO (Status 1) or temporary MCS (Status 2). We examined the impact of the allocation change on HTx candidates listed Status 1A versus Status 3 at a high-volume transplant center. METHODS: Between January 2017 and January 2021, 75 patients were listed with a PA catheter and inotropic support prior to the allocation change (Era 1) and 48 were listed after (Era 2). Clinical characteristics and outcomes were compared for these 123 patients. RESULTS: Heart transplant (HTx) candidates in Era 2 had higher median inotrope doses at listing. There was no significant difference in inpatient wait list days (12 vs. 20 days, P = .15), transition to temporary MCS (33.3% vs. 22.7%, P = .15), or wait list mortality (6.3% vs. 4.0%, P = .68). There was also no significant difference in survival to transplantation (91.7% vs. 94.7%, P = .71). There were no differences in post-transplant outcomes including 1-year survival (88.6% vs. 93.0%, P = .38). CONCLUSION: At a high-volume transplant center, the UNOS allocation change did not result in increased wait list time, use of temporary MCS, or mortality on the waitlist or post-transplant for candidates on inotropic support with continuous hemodynamic monitoring.


Asunto(s)
Fármacos Cardiovasculares , Insuficiencia Cardíaca , Trasplante de Corazón , Humanos , Pacientes Internos , Listas de Espera , Factores de Tiempo , Estudios Retrospectivos
3.
Clin Transplant ; 36(6): e14645, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35293038

RESUMEN

INTRODUCTION: Cardiac involvement may occur in many forms of muscular dystrophy (MD). While cardiac disease may progress to warrant heart transplantation (HTx), there may be contraindications related to extra-cardiac disease including pulmonary and skeletal muscle involvement that limit overall survival and impairs post-transplant rehabilitation efforts. This study describes the MD HTx experience at a single high-volume center. METHODS: We examined the clinical characteristics and outcomes of patients with MD with heart failure (HF) (n = 28), patients with MD status post HTx (n = 20) and non-MD HTx control group (n = 40) matched 2:1 for age at transplant, sex, listing status, and antibody sensitization. RESULTS: Patients with MD who underwent HTx had increased ventilator days (2 vs. 1 days, p = .013), increased hospital length of stay (20 vs. 12 days, p = .022), and increased discharge to inpatient rehab (60% vs. 8%, p < .001). By 1 year post HTx, patients with MD more often required assistive devices for walking (55% vs. 10%, p = .01). Nonetheless, post-HTx survival was similar at 1 year (100% vs. 97.5%, p = .48) and 5 years (95.0% vs. 87.5%, p = .36). Of the HTx recipients with MD, 95% were followed by a neurologist, 60% by a neuromuscular specialist as part of the Muscular Dystrophy Association Clinic at our center. CONCLUSION: Transplantation is a feasible option for patients with MD and advanced HF. MD patients who undergo transplantation may benefit from multidisciplinary specialized care to optimize MD-related morbidity.


Asunto(s)
Cardiopatías , Insuficiencia Cardíaca , Trasplante de Corazón , Distrofias Musculares , Cardiopatías/etiología , Insuficiencia Cardíaca/cirugía , Trasplante de Corazón/efectos adversos , Humanos , Distrofias Musculares/etiología , Distrofias Musculares/cirugía , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
4.
J Nucl Cardiol ; 29(1): 86-96, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32462631

RESUMEN

BACKGROUND: Quantitative assessment of cardiac hypermetabolism from 18Flourodeoxy glucose (FDG) positron emission tomography (PET) may improve diagnosis of cardiac sarcoidosis (CS). We assessed different approaches for quantification of cardiac hypermetabolism and perfusion in patients with suspected CS. METHODS AND RESULTS: Consecutive patients undergoing 18FDG PET assessment for possible CS between January 2014 and March 2019 were included. Cardiac hypermetabolism was quantified using maximal standardized uptake value (SUVMAX), cardiometabolic activity (CMA) and volume of inflammation, using relative thresholds (1.3× and 1.5× left ventricular blood pool [LVBP] activity), and absolute thresholds (SUVMAX > 2.7 and 4.1). Diagnosis of CS was established using the Japanese Ministry of Health and Wellness criteria. In total, 69 patients were studied, with definite or possible CS in 29(42.0%) patients. CMA above 1.5× LVBP SUVMAX had the highest area under the receiver operating characteristic curve (AUC 0.92). Quantitative parameters using relative thresholds had higher AUC compared to absolute thresholds (p < 0.01). Interobserver variability was low for CMA, with excellent agreement regarding absence of activity (Kappa 0.970). CONCLUSIONS: Quantitation with scan-specific thresholds has superior diagnostic accuracy compared to absolute thresholds. Based on the potential clinical benefit, programs should consider quantification of cardiac hypermetabolism when interpreting 18F-FDG PET studies for CS.


Asunto(s)
Cardiomiopatías , Miocarditis , Sarcoidosis , Cardiomiopatías/diagnóstico por imagen , Fluorodesoxiglucosa F18 , Humanos , Perfusión , Tomografía Computarizada por Tomografía de Emisión de Positrones , Tomografía de Emisión de Positrones/métodos , Radiofármacos , Sarcoidosis/diagnóstico por imagen , Tomografía Computarizada por Rayos X
5.
Am J Transplant ; 21(7): 2479-2488, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33251691

RESUMEN

Allosensitization represents a major barrier to heart transplantation (HTx). We assessed the efficacy and safety of complement inhibition at transplant in highly sensitized heart transplant recipients. We performed a single-center, single-arm, open-label trial (NCT02013037). Patients with panel reactive antibodies (PRA) ≥70% and pre-formed donor-specific antibodies (DSA) were eligible. In addition to standard of care, patients received nine infusions of eculizumab during the first 2 months posttransplant. The primary composite endpoint was antibody-mediated rejection (AMR) ≥pAMR2 and/or left ventricular dysfunction during the first year. Secondary endpoints included hemodynamic compromise, allograft rejection, and patient survival. Twenty patients were included. Median cPRA and mean fluorescence intensity of immunodominant DSA were 95% (90%-97%) and 6250 (5000-10 000), respectively. Retrospective B cell and T cell flow crossmatches were positive in 14 and 11 patients, respectively. The primary endpoint occurred in four patients (20%). Survival at 1 year was 90% with no deaths resulting from AMR. In a prespecified analysis comparing treated patients to matched control patients, we observed a dramatic reduction in the risk of biopsy-proven AMR in patients treated with eculizumab (HR = 0.36, 95% CI = 0.14-0.95, p = .032). Our findings support the prophylactic use of complement inhibition for heart transplantation at high immunological risk. ClinincalTrials.gov, NCT02013037.


Asunto(s)
Isoanticuerpos , Trasplante de Riñón , Aloinjertos , Rechazo de Injerto/etiología , Rechazo de Injerto/prevención & control , Antígenos HLA , Humanos , Estudios Retrospectivos
6.
Clin Transplant ; 35(3): e14204, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33368675

RESUMEN

BACKGROUND: Depression is prevalent in patients with heart failure and after heart transplant. We identified the prevalence of pre- and post-transplant depression and its association with clinical characteristics and post-transplant outcomes. METHODS: We reviewed 114 adults transplanted 1/1/2015 to 12/31/2015 and identified patients with pre- and post-transplant depression. Clinical characteristics and outcomes were compared. RESULTS: Of 114 patients, 35.1% had pre-transplant depression and 26.3% had post-transplant depression. Patients with post-transplant depression within the first year were significantly more likely to have acute rejection (10% vs 0%), longer intensive care unit (11.7 days vs 7.8 days) and hospital stay (31.7 days vs 16.3 days), and discharge to inpatient rehabilitation (26.7% vs 8.3%). Patients with post-transplant depression within the first year had significantly higher 5-year mortality (30% vs 9.5%, p = .009). However, after adjustment for total artificial heart/biventricular assist device, acute rejection, intensive care unit, and hospital length of stay, this relationship was no longer significant (HR 2.11; 95% CI 0.18-25.27; p = .556). CONCLUSIONS: Depression is common among heart transplant candidates and recipients. While pre-transplant depression did not impact outcomes, patients with post-transplant depression were more likely to have had a complicated course, suggesting the need for increased vigilance regarding depression in such patients.


Asunto(s)
Trasplante de Corazón , Corazón Auxiliar , Adulto , Estudios de Cohortes , Depresión/epidemiología , Depresión/etiología , Humanos , Estudios Retrospectivos , Resultado del Tratamiento
7.
Clin Transplant ; 35(2): e14181, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33277716

RESUMEN

BACKGROUND: While the revised UNOS HTx donor allocation system aimed to minimize waitlist mortality by prioritizing more critically ill transplant candidates, there is concern for increased post-transplant morbidity and mortality. We examined the impact of the revised allocation system on waitlist and post-transplant outcomes at a high-volume transplant center. METHODS: One hundred and sixty nine adult patients underwent first-time single-organ HTx one year before (Era 1:79 patients) and after (Era 2:90 patients) implementation of the new allocation system (10/18/2018). Clinical characteristics, waitlist outcomes, and post-transplant morbidity and mortality were compared. RESULTS: Era 2 patients were twice as likely to be transplanted on temporary mechanical circulatory support (43% vs. 19%, p < .0001). While Era 2 waitlist time was shorter (10 vs. 43 days, p < .001), exception status requests (21.1% vs. 17.9%) and waitlist mortality (3.3% vs. 2.2%) were similar. There was no difference in primary graft dysfunction, intensive care unit or hospital length of stay, readmissions, rejection, allograft vasculopathy, or 1-year survival (91.1% vs. 93.7%). CONCLUSIONS: In a high-volume center, the revised HTx allocation system shortened waitlist time with no significant change in waitlist mortality or observed impact on post-transplant outcomes. With careful patient selection, the revised allocation system may optimize waitlist and post-transplant outcomes.


Asunto(s)
Trasplante de Corazón , Obtención de Tejidos y Órganos , Adulto , Humanos , Morbilidad , Donantes de Tejidos , Listas de Espera
8.
J Exp Biol ; 222(Pt 7)2019 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-30846535

RESUMEN

Nutrition is involved in regulating multiple aspects of honey bee biology such as caste, immunity, lifespan, growth and behavioral development. Deformed wing virus (DWV) is a major pathogenic factor which threatens honey bee populations, and its replication is regulated by the nutrition status and immune response of honey bees. The alimentary canal of the honey bee is home to a diverse microbial community that provides essential nutrients and serves to bolster immune responses. However, to what extent gut bacteria affect honey bee nutrition metabolism and immunity with respect to DWV has not been investigated fully. In this study, newly emerged worker bees were subjected to four diets that contained (1) pollen, (2) pollen and antibiotics, (3) neither pollen nor antibiotics or (4) antibiotics alone. The expression level of two nutrition genes target of rapamycin (tor) and insulin like peptide (ilp1), one nutritional marker gene vitellogenin (vg), five major royal jellyprotein genes (mrjp1-5), one antimicrobial peptide regulating gene relish (rel), and DWV virus titer and its replication intermediate, negative RNA strand, were determined by qRT-PCR from the honey bees at 7 days post-antibiotic treatment. Additionally, honey bee head mass and survival rate were measured. We observed that antibiotics decreased the expression of tor and rel, and increased DWV titer and its replication activity. Expression of ilp1, mrjp1-5 and vg, and honey bee head mass were also reduced compared with bees on a pollen diet. Antibiotics also caused a significant drop in survivorship, which could be rescued by addition of pollen to the diet. Of importance, pollen could partially rescue the loss of vg and mrjp2 while also increasing the head mass of antibiotic-treated bees. Our results illuminate the roles of bacteria in honey bee nutrition, metabolism and immunity, which confer the ability to inhibit virus replication, extend honey bee lifespan and improve overall health.


Asunto(s)
Bacterias/aislamiento & purificación , Abejas/inmunología , Abejas/microbiología , Polen , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Antibacterianos/administración & dosificación , Bacterias/clasificación , Bacterias/efectos de los fármacos , Abejas/virología , Dieta , Femenino , Microbioma Gastrointestinal/efectos de los fármacos , Expresión Génica , Cabeza/anatomía & histología , Penicilinas/administración & dosificación , Virus ARN/crecimiento & desarrollo , Estreptomicina/administración & dosificación
9.
Clin Transplant ; 33(8): e13648, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31230384

RESUMEN

BACKGROUND: The Organ Care System (OCS), an ex vivo heart perfusion platform, represents an alternative to the current standard of cold organ storage that sustains the donor heart in a near-physiologic state. Previous reports showed that this system had significantly shortened the cold ischemic time from standard cold storage (CS). However, the effect of reduced ischemic injury against the coronary vascular bed has not been examined by intravascular ultrasound (IVUS). METHODS: Between August 2011 and February 2013, heart transplant (HTx) candidates enrolled in the PROCEED 2 trial were randomized to either CS or OCS. IVUS was performed at 4-6 weeks (baseline) and repeated 1 year after transplantation. The change in maximal intimal thickness (MIT) and other clinical outcomes were examined. RESULTS: Thirty-nine patients were randomized and underwent HTx by OCS (n=16) or CS (n=18). Of these, 18 patients (OCS: n=5, CS: n=13) with paired IVUS were examined. There were no significant differences in the change of MIT and other clinical outcomes between the groups. CONCLUSION: The incidence of cardiac allograft vasculopathy in donor hearts preserved with the OCS versus CS was similar. These results suggest that this ex vivo allograft perfusion system is a promising and valid platform for donor heart transportation.


Asunto(s)
Grosor Intima-Media Carotídeo/estadística & datos numéricos , Isquemia Fría , Criopreservación , Trasplante de Corazón/métodos , Preservación de Órganos/métodos , Perfusión , Donantes de Tejidos/provisión & distribución , Circulación Extracorporea , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos
10.
J Exp Biol ; 221(Pt 19)2018 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-30135088

RESUMEN

RNA interference (RNAi) is a post-transcriptional gene silencing mechanism triggered by double-stranded RNA (dsRNA) that is homologous in sequence to the silenced gene and is conserved in a wide range of eukaryotic organisms. The RNAi mechanism has provided unique opportunities for combating honey bee diseases caused by various parasites and pathogens. Nosema ceranae is a microsporidian parasite of European honey bees, Apis mellifera, and has been associated with honey bee colony losses in some regions of the world. Here we explored the possibility of silencing the expression of a N. ceranae putative virulence factor encoding polar tube protein 3 (ptp3) which is involved in host cell invasion as a therapeutic strategy for controlling Nosema parasites in honey bees. Our studies showed that the oral ingestion of a dsRNA corresponding to the sequences of N. ceranae ptp3 could effectively suppress the expression of the ptp3 gene in N. ceranae-infected bees and reduce Nosema load. In addition to the knockdown of ptp3 gene expression, ingestion of ptp3-dsRNA also led to improved innate immunity in bees infected with N. ceranae along with an improvement in physiological performance and lifespan compared with untreated control bees. These results strongly suggest that RNAi-based therapeutics hold real promise for the effective treatment of honey bee diseases in the future, and warrant further investigation.


Asunto(s)
Abejas/inmunología , Nosema/fisiología , Proteínas Protozoarias/genética , Interferencia de ARN , Animales , Apicultura , Abejas/parasitología , Inmunidad Innata , Nosema/genética , Proteínas Protozoarias/metabolismo , ARN Bicatenario/administración & dosificación
11.
J Invertebr Pathol ; 151: 131-136, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29158015

RESUMEN

Viruses, and especially RNA viruses, constantly change and adapt to new host species and vectors, posing a potential threat of new and reemerging infectious diseases. Honey bee Acute bee paralysis virus (ABPV) and Deformed wing virus (DWV) are two of the most common honey bee viruses found in European honey bees Apis mellifera and have been implicated in worldwide Varroa-associated bee colony losses. Previous studies have shown that DWV has jumped hosts several times in history causing infection in multiple host species. In the present study, we show that DWV infection could be detected in the Asian honey bee, A. cerana, and the parasitic mite Tropilaelaps mercedesae, confirming previous findings that DWV is a multi-host pathogen and supporting the notion that the high prevalence of DWV in honey bee host populations could be attributed to the high adaptability of this virus. Furthermore, our study provides the first evidence that ABPV occurs in both A. cerana and T. mercedesae in northern Thailand. The geographical proximity of host species likely played an important role in the initial exposure and the subsequent cross-species transmission of these viruses. Phylogenetic analyses suggest that ABPV might have moved from T. mercedesae to A. mellifera and to A. cerana while DWV might have moved in the opposite direction from A. cerana to A. mellifera and T. mercedesae. This result may reflect the differences in virus life history and virus-host interactions, warranting further investigation of virus transmission, epidemiology, and impacts of virus infections in the new hosts. The results from this study indicate that viral populations will continue to evolve and likely continue to expand host range, increasing the need for effective surveillance and control of virus infections in honey bee populations.


Asunto(s)
Abejas/virología , Dicistroviridae/fisiología , Interacciones Huésped-Parásitos/fisiología , Varroidae/fisiología , Animales
12.
Parasitol Res ; 116(12): 3265-3274, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29104999

RESUMEN

Nosema ceranae causes widespread infection in adult workers of European honey bees, Apis mellifera, and has often been linked to honey bee colony losses worldwide. Previous investigations of honey bee immune response to N. ceranae infection were largely based on laboratory experiment, however, little is known about the immune response of honey bees that are naturally infected by N. ceranae. Here, we compared the infection levels of N. ceranae in three different categories of adult bees (emergent bees, nurses, and foragers) and detected the host immune response to the N. ceranae infection under natural conditions. Our studies showed that the Nosema spore load and infection prevalence varied among the different types of adult workers, and both of them increased as honey bees aged: No infection was detected in emergent bees, nurses had a medium spore load and prevalence, while foragers were with the highest Nosema infection level and prevalence. Quantification of the mRNA levels of antimicrobial peptides (abaecin, apidaecin, defensin-1, defensin-2, and hymenoptaecin) and microbial recognition proteins (PGRP-S1, PGRP-S2, PGRP-S3, PGRP-LC, GNBP1-1, and GNBP1-2) confirmed the involvement of the Toll and/or Imd immune pathways in the host response to N. ceranae infection, and revealed an activation of host immune response by N. ceranae infection under natural conditions. Additionally, the levels of immune response were positively correlated with the Nosema spore loads in the infected bees. The information gained from this study will be relevant to the predictive modeling of honey bee disease dynamics for Nosema disease prevention and management.


Asunto(s)
Abejas/microbiología , Nosema/inmunología , Animales , Péptidos Catiónicos Antimicrobianos/genética , Abejas/genética , Abejas/inmunología , Defensinas/genética , Femenino , Proteínas de Insectos/genética , Nosema/genética , Esporas Fúngicas
13.
PLoS Pathog ; 10(7): e1004261, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25079600

RESUMEN

Israeli acute paralysis virus (IAPV) is a widespread RNA virus of honey bees that has been linked with colony losses. Here we describe the transmission, prevalence, and genetic traits of this virus, along with host transcriptional responses to infections. Further, we present RNAi-based strategies for limiting an important mechanism used by IAPV to subvert host defenses. Our study shows that IAPV is established as a persistent infection in honey bee populations, likely enabled by both horizontal and vertical transmission pathways. The phenotypic differences in pathology among different strains of IAPV found globally may be due to high levels of standing genetic variation. Microarray profiles of host responses to IAPV infection revealed that mitochondrial function is the most significantly affected biological process, suggesting that viral infection causes significant disturbance in energy-related host processes. The expression of genes involved in immune pathways in adult bees indicates that IAPV infection triggers active immune responses. The evidence that silencing an IAPV-encoded putative suppressor of RNAi reduces IAPV replication suggests a functional assignment for a particular genomic region of IAPV and closely related viruses from the Family Dicistroviridae, and indicates a novel therapeutic strategy for limiting multiple honey bee viruses simultaneously and reducing colony losses due to viral diseases. We believe that the knowledge and insights gained from this study will provide a new platform for continuing studies of the IAPV-host interactions and have positive implications for disease management that will lead to mitigation of escalating honey bee colony losses worldwide.


Asunto(s)
Abejas/virología , Colapso de Colonias/epidemiología , Dicistroviridae/patogenicidad , Virosis/epidemiología , Virosis/patología , Animales , Biomarcadores/metabolismo , Colapso de Colonias/genética , Colapso de Colonias/virología , Dicistroviridae/genética , Perfilación de la Expresión Génica , Genoma Viral , Interacciones Huésped-Patógeno , Hibridación in Situ , Análisis de Secuencia por Matrices de Oligonucleótidos , ARN Mensajero/genética , ARN Interferente Pequeño/genética , ARN Viral/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Proteínas Virales/antagonistas & inhibidores , Proteínas Virales/genética , Proteínas Virales/metabolismo , Virosis/genética , Virosis/virología
14.
Appl Environ Microbiol ; 82(22): 6779-6787, 2016 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-27613683

RESUMEN

Nosema ceranae is a new and emerging microsporidian parasite of European honey bees, Apis mellifera, that has been implicated in colony losses worldwide. RNA interference (RNAi), a posttranscriptional gene silencing mechanism, has emerged as a potent and specific strategy for controlling infections of parasites and pathogens in honey bees. While previous studies have focused on the silencing of parasite/pathogen virulence factors, we explore here the possibility of silencing a host factor as a mechanism for reducing parasite load. Specifically, we used an RNAi strategy to reduce the expression of a honey bee gene, naked cuticle (nkd), which is a negative regulator of host immune function. Our studies found that nkd mRNA levels in adult bees were upregulated by N. ceranae infection (and thus, the parasite may use this mechanism to suppress host immune function) and that ingestion of double-stranded RNA (dsRNA) specific to nkd efficiently silenced its expression. Furthermore, we found that RNAi-mediated knockdown of nkd transcripts in Nosema-infected bees resulted in upregulation of the expression of several immune genes (Abaecin, Apidaecin, Defensin-1, and PGRP-S2), reduction of Nosema spore loads, and extension of honey bee life span. The results of our studies clearly indicate that silencing the host nkd gene can activate honey bee immune responses, suppress the reproduction of N. ceranae, and improve the overall health of honey bees. This study represents a novel host-derived therapeutic for honey bee disease treatment that merits further exploration. IMPORTANCE: Given the critical role of honey bees in the pollination of agricultural crops, it is urgent to develop strategies to prevent the colony decline induced by the infection of parasites/pathogens. Targeting parasites and pathogens directly by RNAi has been proven to be useful for controlling infections in honey bees, but little is known about the disease impacts of RNAi silencing of host factors. Here, we demonstrate that knocking down the honey bee immune repressor-encoding nkd gene can suppress the reproduction of N. ceranae and improve the overall health of honey bees, which highlights the potential role of host-derived and RNAi-based therapeutics in controlling the infections in honey bees. The information obtained from this study will have positive implications for honey bee disease management practices.


Asunto(s)
Abejas/genética , Abejas/microbiología , Genes de Insecto , Nosema/fisiología , Interferencia de ARN , Animales , Péptidos Catiónicos Antimicrobianos/genética , Abejas/inmunología , Abejas/fisiología , Defensinas/genética , Interacciones Huésped-Patógeno/genética , Inmunidad Innata/genética , Proteínas de Insectos/genética , Carga de Parásitos , Reacción en Cadena de la Polimerasa , ARN Bicatenario , Esporas Fúngicas
15.
Tumour Biol ; 37(1): 829-35, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26254098

RESUMEN

Rituximab is a chimeric monoclonal antibody directed against the CD20 antigen. Treatment using rituximab in combination with chemotherapy has dramatically improved overall survival rate of diffuse large B cell lymphoma (DLBCL). Since rituximab can deplete both lymphoma B cells and normal B cells, how rituximab-treatment affects normal B cell function in DLBCL patients under remission is unclear. Here, we examined peripheral blood B cell composition and antigen-specific B cell responses in DLBCL patients in remission and observed reductions in the frequencies of total B cell as well as several major B cell subsets, including CD19(+)IgD(+) naive B cells, CD19(+)IgD(-)CD27(+) memory B cells, and CD19(lo)CD27(hi) plasmablasts. Moreover, tetanus toxin (TT)-specific B cell proliferation was reduced in DLBCL patients in remission. On the other hand, HA-specific IgG-secreting B cell responses could be stimulated by influenza vaccination in DLBCL patients in remission, demonstrating that the machinery for generating de novo adaptive B cell responses was functional in DLBCL patients in remission. Our results provided insights in normal B cell function in DLBCL patients in remission.


Asunto(s)
Antineoplásicos/uso terapéutico , Linfocitos B/inmunología , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Linfoma de Células B Grandes Difuso/inmunología , Rituximab/uso terapéutico , Adulto , Antígenos CD19/metabolismo , Proliferación Celular , Ensayo de Inmunoadsorción Enzimática , Femenino , Citometría de Flujo , Humanos , Inmunoglobulina G/inmunología , Linfoma de Células B Grandes Difuso/patología , Masculino , Persona de Mediana Edad , Fenotipo , Inducción de Remisión , Adulto Joven
16.
Rev Cardiovasc Med ; 16(3): 171-81, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26451764

RESUMEN

Tricuspid regurgitation (TR) is a common finding. Pathologic TR is an independent risk factor for mortality. TR can be classified by etiology into functional versus organic. Organic TR is caused by structural damage to the tricuspid valve (TV) by a spectrum of etiologies, including pacemaker leads and right heart biopsies, whereas functional TR is predominantly due to elevated pulmonary pressures. Atrial fibrillation and chamber enlargement, among other risk factors, are strong predictors of functional TR. Correction of elevated pulmonary pressures improves TR, and concurrent repair of severe TR at the time of left heart valve surgery improves postoperative heart failure symptoms but does not improve survival. TR repair is associated with less operative and long-term mortality than TV replacement, and demonstrates similar improvements in heart failure symptoms. Substantial residual TR remains after repair, and reoperative mortality for residual TR is considerable. Percutaneous TV replacement may offer a rescue strategy.

17.
Clin Transplant ; 28(7): 802-7, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24801014

RESUMEN

BACKGROUND: To expand the donor pool, older donors (≥50 yr) are frequently used in older recipients (≥60 yr). Older recipients and those receiving older donor hearts have independently displayed decreased post-transplant survival. However, outcomes in older patients receiving older donor hearts are contentious. METHODS: Eight hundred and seventy-nine heart transplant patients between 2000 and 2010 were analyzed, excluding patients with donor coronary artery disease. From 380 patients ≥60 yr, 327 patients with donors <50 yr old were compared with 53 patients with donors ≥50 yr old for: five-yr actuarial survival, freedom from cardiac allograft vasculopathy (CAV: stenosis ≥30%), non-fatal major adverse cardiac events (NF-MACE: MI, CHF, stroke, need for pacemaker/ICD), one-yr freedom from any treated rejection. RESULTS: The older vs. younger donor group demonstrated significantly lower five-yr survival (57% vs. 85%, p < 0.001) and freedom from CAV (83% vs. 92%, p = 0.03). No difference was observed in five-yr freedom from NF-MACE and one-yr freedom from any treated rejection. Multivariate analysis found donor age ≥50 to be an independent risk factor for death (HR 1.8, CI 1.1-2.9, p = 0.008) and CAV (HR 1.9, CI 1.2-2.9, p = 0.004). CONCLUSIONS: Use of older donors (≥50 yr) in older recipients (≥60 yr) results in lower five-yr survival and freedom from CAV. Caution is required in these cases. Larger studies are warranted to confirm findings.


Asunto(s)
Rechazo de Injerto , Supervivencia de Injerto , Cardiopatías/cirugía , Trasplante de Corazón , Complicaciones Posoperatorias , Donantes de Tejidos , Factores de Edad , Anciano , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Factores de Riesgo , Tasa de Supervivencia , Factores de Tiempo
18.
J Invertebr Pathol ; 120: 18-22, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24825460

RESUMEN

We demonstrated that honey bee viruses including Deformed wing virus (DWV), Black queen cell virus (BQCV) and Israeli acute paralysis virus (IAPV) could infect and replicate in the fungal pathogen Ascosphaera apis that causes honey bee chalkbrood disease, revealing a novel biological feature of honey bee viruses. The phylogenetic analysis show that viruses of fungal and honey bee origins form two clusters in the phylogenetic trees distinctly and that host range of honey bee viruses is dynamic. Further studies are warranted to investigate the impact of the viruses on the fitness of their fungal host and phenotypic effects the virus-fungus combination has on honey bee hosts.


Asunto(s)
Ascomicetos/virología , Abejas/virología , Dicistroviridae/genética , Virus de Insectos/genética , Animales , Filogenia , ARN Viral/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
19.
J Econ Entomol ; 107(1): 54-62, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24665684

RESUMEN

The aim of this study was to improve cage systems for maintaining adult honey bee (Apis mellifera L.) workers under in vitro laboratory conditions. To achieve this goal, we experimentally evaluated the impact of different cages, developed by scientists of the international research network COLOSS (Prevention of honey bee COlony LOSSes), on the physiology and survival of honey bees. We identified three cages that promoted good survival of honey bees. The bees from cages that exhibited greater survival had relatively lower titers of deformed wing virus, suggesting that deformed wing virus is a significant marker reflecting stress level and health status of the host. We also determined that a leak- and drip-proof feeder was an integral part of a cage system and a feeder modified from a 20-ml plastic syringe displayed the best result in providing steady food supply to bees. Finally, we also demonstrated that the addition of protein to the bees' diet could significantly increase the level ofvitellogenin gene expression and improve bees' survival. This international collaborative study represents a critical step toward improvement of cage designs and feeding regimes for honey bee laboratory experiments.


Asunto(s)
Apicultura/instrumentación , Abejas , Métodos de Alimentación , Animales , Abejas/metabolismo , Dieta , Venas , Vitelogeninas/metabolismo , Alas de Animales
20.
JAMA Netw Open ; 7(1): e2352094, 2024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-38231511

RESUMEN

Importance: Heart failure (HF) affects more than 6 million adults in the US and more than 64 million adults worldwide, with 50% prevalence of depression. Patients and clinicians lack information on which interventions are more effective for depression in HF. Objective: To compare the effectiveness of behavioral activation psychotherapy (BA) vs antidepressant medication management (MEDS) on patient-centered outcomes inpatients with HF and depression. Design, Setting, and Participants: This pragmatic randomized comparative effectiveness trial was conducted from 2018 to 2022, including 1-year follow-up, at a not-for-profit academic health system serving more than 2 million people from diverse demographic, socioeconomic, cultural, and geographic backgrounds. Participant included inpatients and outpatients diagnosed with HF and depression, and data were analyzed as intention-to-treat. Data were analyzed from 2022 to 2023. Interventions: BA is an evidence-based manualized treatment for depression, promoting engagement in personalized pleasurable activities selected by patients. MEDS involves the use of an evidence-based collaborative care model with care managers providing coordination with patients, psychiatrists, and primary care physicians to only administer medications. Main Outcomes and Measures: The primary outcome was depressive symptom severity at 6 months, measured using the Patient Health Questionnaire 9-Item (PHQ-9). Secondary outcomes included physical and mental health-related quality of life (HRQOL), measured using the Short-Form 12-Item version 2 (SF-12); heart failure-specific HRQOL, measured using the Kansas City Cardiomyopathy Questionnaire; caregiver burden, measured with the Caregiver Burden Questionnaire for Heart Failure; emergency department visits; readmissions; days hospitalized; and mortality at 3, 6, and 12 months. Results: A total of 416 patients (mean [SD] age, 60.71 [15.61] years; 243 [58.41%] male) were enrolled, with 208 patients randomized to BA and 208 patients randomized to MEDS. At baseline, mean (SD) PHQ-9 scores were 14.54 (3.45) in the BA group and 14.31 (3.60) in the MEDS group; both BA and MEDS recipients experienced nearly 50% reduction in depressive symptoms at 3, 6, and 12 months (eg, mean [SD] score at 12 months: BA, 7.62 (5.73); P < .001; MEDS, 7.98 (6.06); P < .001; between-group P = .55). There was no statistically significant difference between BA and MEDS in the primary outcome of PHQ-9 at 6 months (mean [SD] score, 7.53 [5.74] vs 8.09 [6.06]; P = .88). BA recipients, compared with MEDS recipients, experienced small improvement in physical HRQOL at 6 months (mean [SD] SF-12 physical score: 38.82 [11.09] vs 37.12 [10.99]; P = .04), had fewer ED visits (3 months: 38% [95% CI, 14%-55%] reduction; P = .005; 6 months: 30% [95% CI, 14%-40%] reduction; P = .008; 12 months: 27% [95% CI, 15%-38%] reduction; P = .001), and spent fewer days hospitalized (3 months: 17% [95% CI, 8%-25%] reduction; P = .002; 6 months: 19% [95% CI, 13%-25%] reduction; P = .005; 12 months: 36% [95% CI, 32%-40%] reduction; P = .001). Conclusions and Relevance: In this comparative effectiveness trial of BA and MEDS in patients with HF experiencing depression, both treatments significantly reduced depressive symptoms by nearly 50% with no statistically significant differences between treatments. BA recipients experienced better physical HRQOL, fewer ED visits, and fewer days hospitalized. The study findings suggested that patients with HF could be given the choice between BA or MEDS to ameliorate depression. Trial Registration: ClinicalTrials.gov Identifier: NCT03688100.


Asunto(s)
Depresión , Insuficiencia Cardíaca , Adulto , Humanos , Masculino , Persona de Mediana Edad , Femenino , Depresión/tratamiento farmacológico , Calidad de Vida , Psicoterapia , Antidepresivos/uso terapéutico , Insuficiencia Cardíaca/terapia
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