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1.
Plant Dis ; 108(3): 666-670, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37807093

RESUMO

Green mold (Trichoderma aggressivum) is an invasive disease of commercial mushrooms introduced into the United States from Europe that now has spread to commercial mushrooms throughout North America. We examined potential sources of invasive green mold inoculum and the association with different compost filling technologies on a large actively producing commercial mushroom farm. Green mold foci were sampled bed by bed, which generated 20,906 data points. Logistic regression was used to determine treatment differences. Mechanical filling of compost into the beds reduced green mold incidence over hand filling, apparently due to the reduced incidence of worker contact with the floor and between beds. Lower growing beds located closer to the floor had a higher incidence of green mold for both mechanical and hand-filled beds. We conclude that mechanical filling and generally reducing contact with the floor and between beds will reduce spread of green mold in commercial mushroom production.


Assuntos
Agaricus , Compostagem , Trichoderma , Estados Unidos , Incidência , Europa (Continente)
2.
J Occup Rehabil ; 34(1): 4-36, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37067701

RESUMO

PURPOSE: Previous research has systematically studied the effectiveness of Cognitive Behavioral Therapy (CBT)-based interventions in managing both mental and physical symptoms of chronic disease including depression, stress-related mental disorders (SMD), and chronic pain that are common causes of sick leave. However, a systematic review focusing on the effectiveness of CBT in facilitating RTW is lacking. This study compiles research on utilizing CBT-based interventions for helping employees on sick leave return to work. METHODS: Randomized controlled trials (RCT) published between 1 January 1990 and 27 June 2022 were searched in MEDLINE, EMBASE, The Cochrane Library, Scopus, PsycINFO, Web of Science, and PubMed. The primary outcome variables included a return to work (RTW) measure and sickness absences. The secondary outcomes include psychological conditions (mental illness, stress, anxiety, and depression) and physical condition (working ability, fatigue, and physical function). RESULTS: Thirty-four RCTs were included in the analysis. Fifteen RCTs with 1727 participants reported on sick leave. Results showed that participants who completed CBT intervention had reduced sick leave in days (mean reduction - 3.654; 95%CI - 5.253, - 2.046; p < 0.001) compared to the control group. Sixteen papers with 2298 participants reported that the intervention group RTW 1.5 days earlier (95%CI 1.019, 1.722; p < 0.05). CBT-based interventions were effective in managing fatigue, mental illness, and depression, and improving physical function while it showed no effects in managing stress, anxiety and working ability. CONCLUSIONS: The findings indicate that CBT-based interventions are effective in reducing the length of sick leave and facilitating the RTW of employees in the intervention group.


Assuntos
Terapia Cognitivo-Comportamental , Retorno ao Trabalho , Humanos , Retorno ao Trabalho/psicologia , Licença Médica , Terapia Cognitivo-Comportamental/métodos , Emprego , Ansiedade , Transtornos Psicofisiológicos
3.
J Neurosci ; 42(6): 1090-1103, 2022 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-34980636

RESUMO

Strong inhibitory synaptic gating of dentate gyrus granule cells (GCs), attributed largely to fast-spiking parvalbumin interneurons (PV-INs), is essential to maintain sparse network activity needed for dentate dependent behaviors. However, the contribution of PV-INs to basal and input-driven sustained synaptic inhibition in GCs and semilunar granule cells (SGCs), a sparse morphologically distinct dentate projection neuron subtype, is currently unknown. In studies conducted in hippocampal slices from mice, we find that although basal IPSCs are more frequent in SGCs and optical activation of PV-INs reliably elicited IPSCs in both GCs and SGCs, optical suppression of PV-INs failed to reduce IPSC frequency in either cell type. Amplitude and kinetics of IPSCs evoked by perforant path (PP) activation were not different between GCs and SGCs. However, the robust increase in sustained polysynaptic IPSCs elicited by paired afferent stimulation was lower in SGCs than in simultaneously recorded GCs. Optical suppression of PV-IN selectively reduced sustained IPSCs in SGCs but not in GCs. These results demonstrate that PV-INs, while contributing minimally to basal synaptic inhibition in both GCs and SGCs in slices, mediate sustained feedback inhibition selectively in SGCs. The temporally selective blunting of activity-driven sustained inhibitory gating of SGCs could support their preferential and persistent recruitment during behavioral tasks.SIGNIFICANCE STATEMENT Our study identifies that feedback inhibitory regulation of dentate semilunar granule cells (SGCs), a sparse and functionally distinct class of projection neurons, differs from that of the classical projection neurons, GCs. Notably, we demonstrate relatively lower activity-dependent increase in sustained feedback inhibitory synaptic inputs to SGCs when compared with GCs which would facilitate their persistent activity and preferential recruitment as part of memory ensembles. Since dentate GC activity levels during memory processing are heavily shaped by basal and feedback inhibition, the fundamental differences in basal and evoked sustained inhibition between SGCs and GCs characterized here provide a framework to reorganize current understanding of the dentate circuit processing.


Assuntos
Giro Denteado/fisiologia , Inibição Neural/fisiologia , Neurônios/fisiologia , Animais , Potenciais Pós-Sinápticos Inibidores/fisiologia , Interneurônios/fisiologia , Camundongos , Parvalbuminas/metabolismo , Sinapses/fisiologia
4.
J Neurosci ; 33(30): 12218-28, 2013 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-23884930

RESUMO

The neural mechanisms that support the late postnatal development of spatial navigation are currently unknown. We investigated this in rats and found that an increase in the duration of AMPAR-mediated synaptic responses in the hippocampus was related to the emergence of spatial navigation. More specifically, spontaneous alternation rate, a behavioral indicator of hippocampal integrity, increased at the end of the third postnatal week in association with increases in AMPAR response duration at SC-CA1 synapses and synaptically driven postsynaptic discharge of CA1 pyramidal neurons. Pharmacological prolongation of glutamatergic synaptic transmission in juveniles increased the spontaneous alternation rate and CA1 postsynaptic discharge and reduced the threshold for the induction of activity-dependent synaptic plasticity at SC-CA1 synapses. A decrease in GluA1 and increases in GluA3 subunit and transmembrane AMPAR regulatory protein (TARP) expression at the end of the third postnatal week provide a molecular explanation for the increase in AMPAR response duration and reduced efficacy of AMPAR modulators with increasing age. A shift in the composition of AMPARs and increased association with AMPAR protein complex accessory proteins at the end of the third postnatal week likely "turns on" the hippocampus by increasing AMPAR response duration and postsynaptic excitability and reducing the threshold for activity-dependent synaptic potentiation.


Assuntos
Região CA1 Hipocampal/crescimento & desenvolvimento , Região CA1 Hipocampal/fisiologia , Aprendizagem em Labirinto/fisiologia , Receptores de AMPA/fisiologia , Percepção Espacial/fisiologia , Fatores Etários , Animais , Canais de Cálcio/fisiologia , Eletrofisiologia , Potenciais Evocados/fisiologia , Potenciais Pós-Sinápticos Excitadores/fisiologia , Feminino , Masculino , Plasticidade Neuronal/fisiologia , Técnicas de Cultura de Órgãos , Oxazinas/farmacologia , Ratos , Ratos Long-Evans , Receptores de AMPA/agonistas , Sinapses/fisiologia
5.
Eye (Lond) ; 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38555400

RESUMO

BACKGROUND/OBJECTIVES: Tessellated fundus can exist in normal healthy eyes. This study aims to evaluate the occurrence and influencing factors of tessellated fundus in preschool children aged 3-6 years. SUBJECTS/METHODS: This kindergarten-based cross-sectional study included 1716 children with an age range of 3-6 years. All participants underwent a comprehensive eye examination and a questionnaire. According to the number of quadrants occupied by tessellated fundus around the optic disc in fundus photographs, it was divided into four grades. RESULTS: 600 (35.0%) children had peripapillary tessellation. According to the spherical equivalent (SE), the subjects were divided into three groups: Hyperopia group (SE > + 0.75D, n = 1194);Pre-myopia group (-0.50D < SE ≤ + 0.75D, n = 455); Myopia group (SE ≤ -0.50D, n = 67). The proportion of peripapillary tessellated fundus was 33.0%, 38.0%, 50.7% respectively. According to the regression analysis, in the non-myopia group (Pre-myopia group and Hyperopia group), the occurrence of peripapillary tessellated fundus was associated with longer axial length (OR, 1.566; 95% CI: 1.229-1.996, p < 0.001) and larger corneal radius of curvature (OR, 1.837; 95% CI: 1.006-3.354, p = 0.048). However, in Pre-myopia group, the corneal radius of curvature was not associated with the occurrence of peripapillary tessellated fundus (p = 0.830). In Hyperopia group, the corneal radius of curvature was associated with the occurrence of peripapillary tessellated fundus (OR, 2.438; 95% CI: 1.160-5.122, p = 0.019). CONCLUSIONS: The occurrence of peripapillary tessellated fundus is more than 30% in 3-6 year old preschool children. Tessellated fundus can also occur in non-myopic children, and is related to the length of axial length and large radius of corneal curvature.

6.
J Glob Health ; 13: 04077, 2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37539855

RESUMO

Background: Past studies have identified determinants of growth failure (GF) such as socio-economic, nutritional, parenting, and inequality factors. However, few studies investigate the numerous causes of GF across multiple countries. By analysing the data of children under five in 25 low and middle-income countries, this study aims to examine the correlations of determinants with GF to identify the strongest modifiable risk factors. Methods: Cross-sectional study design was used, and data were collected across 25 LMICs by the United Nations Children's Fund in 2019. Regions and households were randomly selected in participating LMICs. The four outcome measures were stunting, wasting, underweight and low body mass index (BMI). Results: Multilevel analysis was performed to identify the impact of country, suburb, and household levels on the variance of outcome variables. GF measures were significantly correlated with low gross domestic product (GDP) per capita (odds ratio (OR) = 2.482), rural areas (OR = 1.223), lack of health insurance (OR = 1.474), low maternal education (OR = 2.260), lack of plain water (OR = 1.402), poor maternal physical caregiving ability (OR = 1.112), low carbohydrate consumption (OR = 1.470), and continued breastfeeding in children >12 months old (OR = 0.802). Conclusions: By identifying key GF risk factors, this study may provide valuable insights for policymaking and interventions. This may allow the prioritisation of resources within countries for preventative measures to be developed.


Assuntos
Aleitamento Materno , Países em Desenvolvimento , Feminino , Criança , Humanos , Lactente , Estudos Transversais , Magreza , Transtornos do Crescimento/epidemiologia
7.
Diabetes Res Clin Pract ; 201: 110727, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37217016

RESUMO

BACKGROUND: Type 2 diabetes mellitus (T2DM) is a rising global health concern that requires long-term treatment and close monitoring. Telemonitoring has been shown to be a promising tool to facilitate patient-physician interaction and improve glycaemic control. METHOD: Randomised controlled trials (RCT) of telemonitoring in T2DM published between 1990 and 2021 were searched through multiple electronic databases. The primary outcome variables included HbA1c and fasting blood glucose (FBG), and BMI was a secondary outcome variable. RESULTS: Thirty RCT with a total of 4,678 participants were included in this study. Twenty-six studies reported on HbA1c, which was shown to be significantly lower in participants on telemonitoring when compared to conventional care. Ten studies investigated FBG which collectively showed no statistically significant difference. Subgroup analysis demonstrated the effect of telemonitoring on glycaemic control is influenced by a range of factors concerning system practicality, user engagement, patient characteristics and disease education. CONCLUSION: Telemonitoring exhibited a great potential to improve T2DM management. Several technical features and patient factors may influence the effectiveness of telemonitoring. Further studies are needed to verify the findings and address limitations before its implementation into routine practice.


Assuntos
Diabetes Mellitus Tipo 2 , Controle Glicêmico , Humanos , Hemoglobinas Glicadas , Diabetes Mellitus Tipo 2/complicações , Glicemia
8.
J Int Med Res ; 48(12): 300060520978015, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33322976

RESUMO

BACKGROUND: Bone homeostasis is a tightly orchestrated process maintained by osteoblasts and osteoclasts, and a disruption of their steady-state equilibrium can lead to the occurrence of osteoporosis (OP). METHODS: We investigated the differential expression of micro (mi)RNAs in the bone tissues of a postmenopausal osteoporosis rat model induced by ovariectomy (OVX). Real-time PCR was used to verify the differentially expressed miRNAs in bone samples from OP patients and controls. The specific targets of two differentially expressed miRNAs in osteogenic or osteoclast differentiation were determined by bioinformatic prediction, and mRNA and protein detection. RESULTS: miR-708-5p and miR-708-3p were highly expressed in the bone tissue of OVX rats and OP patients. miR-708-5p negatively regulated osteoblast differentiation in bone marrow mesenchymal stem cells by targeting SMAD specific E3 ubiquitin protein ligase 2, while miR-708-3p positively regulated osteoclast differentiation in bone marrow monocytes by targeting cerebellar degeneration associated protein 1 antisense RNA. miR-708-5p and miR-708-3p were shown to originate from the same precursor miRNA and to have a synergistic effect on the development of osteoporosis with different temporal and spatial patterns. CONCLUSION: Our findings provide a referential theoretical basis and targets for the prevention and treatment of osteoporosis.


Assuntos
MicroRNAs , Osteoporose , Animais , Diferenciação Celular , Feminino , Humanos , MicroRNAs/genética , Osteoblastos , Osteogênese , Osteoporose/genética , Ratos
9.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 37(1): 112-4, 122, 2006 Jan.
Artigo em Zh | MEDLINE | ID: mdl-16468656

RESUMO

OBJECTIVE: To investigate the relation between TGF-beta1 in allograft and chronic allograft nephropathy (CAN). METHODS: The levels of urine TGF-beta1 were tested in 146 recipients whose renal function were normal from September 1, 2000 to January 31, 2001. Twenty recipients with the highest level of urine TGF-beta1 were classified in group A, while 20 other recipients with the lowest level of urine TGF-beta1 were classified in group B. In these two groups biopsies were carried out in 14 cases and 12 cases respectively, and TGF-beta1 mRNA in the biopsies was measured by RT-PCR. The levels of TGF-beta1 in the blood were also measured in the two groups. Three years later, the renal function was compared between the two groups. Biopsies were carried out in renal recipients whose creatinine is higher than normal. RESULTS: The level of TGF-beta1 in the blood showed no significant difference between the two groups; 3 years after transplantation, the loss of renal function in group A was severer than that in group B. The number levels of CAN cases in group A was larger than that in group B. The expression levels of TGF-beta1 and TGF-beta1 mRNA of the allografts were higher in group A than in group B; there were statistically significant differences between the two groups. CONCLUSION: The findings suggest that there is an association between TGF-beta1 in kidneys and CAN. The level of urine TGF-beta1 after renal transplantation may predict future renal function.


Assuntos
Falência Renal Crônica/etiologia , Transplante de Rim/efeitos adversos , Fator de Crescimento Transformador beta1/genética , Feminino , Humanos , Falência Renal Crônica/diagnóstico , Masculino , Valor Preditivo dos Testes , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Crescimento Transformador beta1/sangue , Fator de Crescimento Transformador beta1/urina
10.
Diabetes ; 51(2): 265-70, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11812731

RESUMO

Recent success using a steroid-free immunosuppressive regimen has renewed enthusiasm for the use of islet transplantation to treat diabetes. Toxicities associated with the continued use of a calcineurin inhibitor may limit the wide-spread application of this therapy. Biological agents that block key T-cell costimulatory signals, in particular the CD28 pathway, have demonstrated extraordinary promise in animal models. LEA29Y (BMS-224818), a mutant CTLA4-Ig molecule with increased binding activity, was evaluated for its potential to replace tacrolimus and protect allogeneic islets in a preclinical primate model. Animals received either the base immunosuppression regimen (rapamycin and anti-IL-2R monoclonal antibody [mAb]) or the base immunosuppression and LEA29Y. Animals receiving the LEA29Y/rapamycin/anti-IL-2R regimen (n = 5) had significantly prolonged islet allograft survival (204, 190, 216, 56, and >220 days). In contrast, those animals receiving the base regimen alone (n = 2) quickly rejected the transplanted islets at 1 week (both at 7 days). The LEA29Y-based regimen prevented the priming of anti-donor T- and B-cell responses, as detected by interferon-gamma enzyme-linked immunospot and allo-antibody production, respectively. The results of this study suggest that LEA29Y is a potent immunosuppressant that can effectively prevent rejection in a steroid-free immunosuppressive protocol and produce marked prolongation of islet allograft survival in a preclinical model.


Assuntos
Antígenos de Diferenciação/uso terapêutico , Antígenos CD28/efeitos dos fármacos , Imunoconjugados , Imunossupressores/uso terapêutico , Transplante das Ilhotas Pancreáticas , Abatacepte , Animais , Anticorpos Monoclonais/uso terapêutico , Antígenos CD , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Antígeno CTLA-4 , Inibidores de Calcineurina , Quimioterapia Combinada , Sobrevivência de Enxerto/efeitos dos fármacos , Transplante das Ilhotas Pancreáticas/imunologia , Macaca mulatta , Receptores de Interleucina-2/imunologia , Sirolimo/uso terapêutico , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Doadores de Tecidos , Transplante Homólogo
11.
J Neurophysiol ; 97(4): 2769-79, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17251359

RESUMO

Locally projecting inhibitory interneurons play a crucial role in the patterning and timing of network activity. However, because of their relative inaccessibility, little is known about their development or incorporation into circuits. In this report we demonstrate that the GABAergic R-interneuron circuit undergoes a reorganization in the chick embryo spinal cord between embryonic days 8 and 15 (E8 and E15). R-interneurons receive synaptic input from and project back to motoneurons. By stimulating motoneurons projecting in one ventral root and recording the disynaptic response from motoneurons in adjacent segments, we show that the output of the R-interneuron circuit is reorganized during development. After stimulation of the LS2 ventral root, disynaptic responses observed in whole cell recordings became more common and stronger for LS3 motoneurons and less common for the more distant LS4 motoneurons from E8 to E10. Optical studies demonstrated that R-interneurons activated by LS2 stimulation were restricted to the LS2 segment and had a small glutamatergic component at both E8 and E10, but that more R-interneurons were activated within the segment by E10. The recruitment of more LS2 R-interneurons at E10 is likely to contribute to stronger projections to LS3 motoneurons, but the fact that fewer LS4 motoneurons receive this input is more consistent with a functional refinement of the more distant projection of the GABAergic R-interneuron. Interestingly, this pattern of reorganization was not observed throughout the rostrocaudal extent of the cord, introducing the possibility that refinement could serve to remove connections between functionally unrelated interneurons and motoneurons.


Assuntos
Interneurônios/fisiologia , Rede Nervosa/embriologia , Rede Nervosa/fisiologia , Ácido gama-Aminobutírico/fisiologia , Animais , Sinalização do Cálcio/fisiologia , Embrião de Galinha , Estimulação Elétrica , Eletrofisiologia , Desenvolvimento Embrionário/fisiologia , Potenciais Evocados/fisiologia , Processamento de Imagem Assistida por Computador , Neurônios Motores/fisiologia , Raízes Nervosas Espinhais/fisiologia
12.
J Neurophysiol ; 93(5): 2922-33, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15574794

RESUMO

Locally projecting inhibitory interneurons play a crucial role in the patterning and timing of network activity. However, because of their relative inaccessibility, little is known about their development or incorporation into circuits. In this study, we characterized the functional onset, neurotransmitters, rostrocaudal spread, and funicular distribution of one such spinal interneuronal circuit during development. The R-interneuron is the avian homologue of the mammalian Renshaw cell. Both cell types receive input from motoneuron recurrent collaterals and make direct connections back onto motoneurons. By stimulating motoneurons projecting in a given ventral root and recording the response in adjacent ventral roots, we demonstrate that the R-interneuron circuit becomes functional between embryonic day 6 (E6) and E7. This ventral root response is observed at E11 and at E14 until it can no longer be detected at E16. Using bath-applied neurotransmitter receptor antagonists, we were able to demonstrate that the circuit is predominately nicotinic and GABAergic from E7.5 to E15. We also found a glutamatergic component to the pathway throughout this developmental period. The R-interneuron projects three or more segments both rostrally and caudally through the ventrolateral funiculus. The distribution of this circuit may become more locally focused between E7.5 and E15.


Assuntos
Interneurônios/fisiologia , Rede Nervosa/embriologia , Inibição Neural/fisiologia , Medula Espinal/citologia , 2-Amino-5-fosfonovalerato/farmacologia , 6-Ciano-7-nitroquinoxalina-2,3-diona/farmacologia , Fatores Etários , Análise de Variância , Animais , Bicuculina/farmacologia , Embrião de Galinha , Interações Medicamentosas , Estimulação Elétrica/métodos , Embrião de Mamíferos , Embrião não Mamífero , Antagonistas de Aminoácidos Excitatórios/farmacologia , Antagonistas GABAérgicos/farmacologia , Glicinérgicos/farmacologia , Técnicas In Vitro , Interneurônios/classificação , Interneurônios/efeitos dos fármacos , Interneurônios/efeitos da radiação , Mecamilamina/farmacologia , Rede Nervosa/citologia , Redes Neurais de Computação , Antagonistas Nicotínicos/farmacologia , Medula Espinal/embriologia , Raízes Nervosas Espinhais/efeitos dos fármacos , Raízes Nervosas Espinhais/embriologia , Raízes Nervosas Espinhais/fisiologia , Estricnina/farmacologia
13.
J Mol Cell Cardiol ; 35(9): 1083-92, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12967631

RESUMO

UNLABELLED: Knowledge of postnatal modulation of I(to) in human atrial myocytes is quite limited. The present study investigated the differences in I(to) properties between neonatal and adult human atrial myocytes. METHODS: Atrial myocytes were dissociated enzymatically from biopsies of human right atrial appendage. I(to) and action potentials were recorded by whole-cell patch-clamp technique. The expressed protein levels of Kv4.3 and KChIP2 in atrial tissue were detected by western blot technique. RESULTS: I(to) was present in all atrial cells (n = 37) from 10 neonatal patients (2.5-7 months). The mean value of I(to) density in neonatal atrial cells was significantly larger than in adult atrial cells. The time constants for I(to) current decay were significantly faster for neonatal cells, compared to adult cells. I(to) recovery from inactivation at holding potential of - 80 mV was significantly slower for neonatal atrial cells than for adult atrial cells. There was no difference in the voltage dependence of I(to) activation between neonatal and adult cells. The voltage-dependent inactivation slope factor was smaller for neonatal compared to adult atrial cells. A more significant frequency-dependent suppression of I(to) peak current and a more significant lengthening of APD(30) were observed in neonatal atrial cells compared to adult atrial cells. Western blots showed both Kv4.3 and KChIP2 are expressed in neonatal atria, but with significantly higher level of Kv4.3 and lower level of KChIP2 protein compared to adult. CONCLUSION: There are significant differences in the properties of I(to) between neonatal and adult human atrial cells, including a larger current density, faster inactivation and slower recovery from inactivation in the neonatal atrial cells. The physiological differences of I(to) are consistent with the different expression protein levels of Kv4.3 and KChIP2.


Assuntos
Potenciais de Ação , Átrios do Coração/fisiopatologia , Miócitos Cardíacos/fisiologia , Canais de Potássio de Abertura Dependente da Tensão da Membrana , Adulto , Idoso , Animais , Biópsia , Western Blotting , Células COS , Proteínas de Ligação ao Cálcio/metabolismo , Separação Celular , Chlorocebus aethiops , Feminino , Átrios do Coração/metabolismo , Humanos , Lactente , Cinética , Proteínas Interatuantes com Canais de Kv , Masculino , Pessoa de Meia-Idade , Miocárdio/citologia , Miócitos Cardíacos/metabolismo , Técnicas de Patch-Clamp , Canais de Potássio/metabolismo , Canais de Potássio Shal
14.
J Immunol ; 169(5): 2677-84, 2002 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-12193741

RESUMO

We have previously described a nonirradiation-based regimen combining costimulation blockade, busulfan, and donor bone marrow cells that promotes stable, high level chimerism, deletion of donor-reactive T cells, and indefinite survival of skin allografts in mice. The purpose of the current study is to determine the efficacy of this tolerance regimen in preventing acute and chronic rejection in a vascularized heart graft model and to compare this regimen with other putative tolerance protocols. Mice receiving costimulation blockade (CTLA4-Ig and anti-CD40 ligand) alone or in combination with donor cells enjoyed markedly prolonged heart graft survival and initially preserved histological structure. However, tolerance was not achieved, as evidenced by the eventual onset of chronic rejection characterized by obliterative vasculopathy and the rejection of secondary skin grafts. In contrast, following treatment with costimulation blockade, busulfan, and bone marrow, heart grafts survived indefinitely without detectable signs of chronic rejection or structural damage, even 100 days after placement of a secondary donor skin graft. We detected multilineage chimerism in peripheral blood, spleen, lymph nodes, and thymus, and peripheral deletion of donor-reactive cells was complete by day 90. These findings indicate that only the CD40/CD28 blockade chimerism induction regimen prevents both acute and chronic rejection of vascularized organ transplants. Further testing of these strategies in a preclinical large animal model is warranted.


Assuntos
Regulação para Baixo/imunologia , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/prevenção & controle , Transplante de Coração/imunologia , Tolerância Imunológica , Ativação Linfocitária , Quimeras de Transplante/imunologia , Condicionamento Pré-Transplante/métodos , Doença Aguda , Animais , Células da Medula Óssea/imunologia , Transplante de Medula Óssea/imunologia , Bussulfano/uso terapêutico , Doença Crônica , Deleção Clonal/genética , Regulação para Baixo/genética , Rejeição de Enxerto/genética , Rejeição de Enxerto/patologia , Sobrevivência de Enxerto/genética , Sobrevivência de Enxerto/imunologia , Transplante de Coração/métodos , Transplante de Coração/patologia , Hematopoese/genética , Hematopoese/imunologia , Tolerância Imunológica/genética , Imunossupressores/uso terapêutico , Ativação Linfocitária/genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Especificidade de Órgãos/genética , Especificidade de Órgãos/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/biossíntese , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo
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