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1.
J Surg Oncol ; 121(1): 153-162, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31152457

RESUMO

BACKGROUND: Reported ischemia time of vascularized lymph nodes was 5 hours. This study investigated the effects of arterial ischemia and venous occlusion on vascularized lymph node function in rats. METHODS: Bilateral pedicled groin lymph node flaps were raised in 27 Lewis rats. Femoral artery and vein were separated and clamped for 1, 3, 4, or 5 hour(s). Lymph node flap perfusion and drainage were assessed by laser Doppler flowmetry and indocyanine green lymphography. Histologic changes were assessed using hematoxylin and eosin stain, terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL), and glutathione assays. RESULTS: Perfusion units of 2.84 ± 1.41, 2.46 ± 0.64, 2.42 ± 0.37, and 2.01 ± 0.90 were measured in arterial ischemia groups, and 1.71 ± 0.45, 2.20 ± 0.98, 1.49 ± 0.35, and 0.81 ± 0.20 in venous occlusion groups after 1, 3, 4, and 5 hours of clamping, respectively. Lymphatic drainage showed mean latency periods of 5.33 ± 0.88, 9.00 ± 3.21, 10.00 ± 2.08, and 24.50 ± 11.50 seconds in arterial clamping groups, and 25.00 ± 3.61, 26.00 ± 3.06, 23.33 ± 4.41, and 152.00 ± 0 seconds in venous clamping groups, respectively. Severe medullary and cortical congestion and hemorrhage on histology and cell damage by glutathione levels and TUNEL assay were found after 4 hours of venous clamping. CONCLUSIONS: Arterial ischemia and venous occlusion impact the function and viability of vascularized lymph node flaps differently. The critical venous occlusion time was 4 hours.


Assuntos
Isquemia/fisiopatologia , Linfonodos/irrigação sanguínea , Retalhos Cirúrgicos/irrigação sanguínea , Doenças Vasculares/fisiopatologia , Animais , Drenagem , Artéria Femoral/fisiopatologia , Virilha , Linfonodos/transplante , Masculino , Perfusão , Ratos , Ratos Endogâmicos Lew
2.
Gene ; 724: 144151, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31626959

RESUMO

BACKGROUND: Differentiation of mesenchymal stem cells (MSCs) into Schwann-like cells onto processed nerve allografts may support peripheral nerve repair. The purpose of this study was to understand the biological characteristics of undifferentiated and differentiated MSCs before and after seeding onto a processed nerve allograft by comparing gene expression profiles. METHODS: MSCs from Lewis rats were cultured in maintenance media or differentiated into Schwann-like cells. Both treatment groups were dynamically seeded onto decellularized nerve allografts derived from Sprague-Dawley rats. Gene expression was quantified by quantitative polymerase chain reaction (qPCR) analysis of representative biomarkers, including neurotrophic (GDNF, PTN, GAP43, PMP22), angiogenic (CD31, VEGF1), extracellular matrix (ECM) (COL1A1, COL3A1, FBLN1, LAMB2) or cell cycle (CAPS3, CCBN2) genes. Gene expression values were statistically evaluated using a 2-factor ANOVA with repeated measures. RESULTS: Baseline gene expression of undifferentiated and differentiated MSCs was significantly altered upon interaction with processed nerve allografts. Interaction between processed allografts and undifferentiated MSCs enhanced expression of neurotrophic (NGF, GDNF, PMP22), ECM (FBLN1, LAMB2) and regulatory cell cycle genes (CCNB2) during a 7-day time course. Interactions of differentiated MSCs with nerve allografts enhanced expression of neurotrophic (NGF, GDNF, GAP43), angiogenic (VEGF1), ECM (FBLN1) and regulatory cell cycle genes (CASP3, CCNB2) within one week. CONCLUSIONS: Dynamic seeding onto processed nerve allografts modulates temporal gene expression profiles of differentiated and undifferentiated MSCs. These changes in gene expressions may support the reparative functions of MSCs in supporting nerve regeneration in different stages of axonal growth.


Assuntos
Diferenciação Celular/genética , Células-Tronco Mesenquimais/citologia , Nervo Isquiático/transplante , Transcriptoma , Tecido Adiposo/citologia , Aloenxertos , Animais , Técnicas de Cultura de Células/métodos , Matriz Extracelular/genética , Células-Tronco Mesenquimais/fisiologia , Neovascularização Fisiológica/genética , Regeneração Nervosa , Ratos Endogâmicos Lew , Ratos Sprague-Dawley , Células de Schwann/citologia , Nervo Isquiático/citologia , Fatores de Tempo , Transplante Homólogo
3.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 50(4): 471-477, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31642221

RESUMO

OBJECTIVE: To determinethe diagnostic valuesand reliabilityof cardiac magnetic resonance tissue tracking (CMR-TT) derived two-dimensional(2D) and three-dimensional(3D) strains in assessing experimental autoimmunity myocarditis (EAM) in rats. METHODS: 20 Lewis rats were randomly divided into model and control groups. The animal model of autoimmune myocarditis was induced by injecting porcine cardiac myosin into the footpads of the rats.On day 35, all of the rats were examined using the 7.0T CMR cine scan. The cardiac function and global strain of the left ventricular of the rats were analyzed with specific cardiac post-processing. The rats were then sacrificed and myocardial samples were taken and stained with HE and Masson. The diagnostic values of the strain parameters were assessed by receiver operating characteristic (ROC) curves with the pathological results as diagnostic criteria.The reliability of the strain parameters were tested using interclass correlation coefficient (ICC), coefficients of variation (CV) and Bland-Altman. RESULTS: No abnormal pathological changes in myocardial cells were found in the control group. Myocarditis was successfully induced in all of the rats in the model group, showing myocardial fiber arrangement disorder, degeneration, necrosis, inflammatory cell infiltration and interstitial fibrosis. The ROC showed that 2D global strain parameters possessed higher diagnostic values than 3D strain parameters. The 2D had an area under the curve (AUC) of 0.96 in global circumferential strain (GCS), 0.95 in global radial strain (GRS), and 0.90 in global longitudinal strain (GLS), compared with 0.87 GCS, 0.85 GRS, and 0.77 GLS in the 3D, respectively.The reliability of the 2D strain parameters was high, except for inter-observer 2D GRS(ICC=0.893). The 3D strain parameters had lower reliability (ICCs:0.421-0.79) than the 2D strain parameters (ICCs:0.893-0.986). CONCLUSION: The diagnostic values of 2D strain parameters are higher than 3D strain parameters in diagnosing myocarditis.


Assuntos
Doenças Autoimunes/diagnóstico por imagem , Imagem Cinética por Ressonância Magnética , Miocardite/diagnóstico por imagem , Animais , Modelos Animais de Doenças , Distribuição Aleatória , Ratos , Ratos Endogâmicos Lew , Reprodutibilidade dos Testes , Suínos , Função Ventricular Esquerda
4.
Int J Mol Med ; 44(3): 1127-1138, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31257463

RESUMO

Due to their high prevalence, blunt chest trauma (TxT) and hemorrhagic shock have a significant influence on the outcomes of trauma patients, causing severe modulations of the immune system and high mortality rates. Alcohol consumption in trauma patients has a high clinical impact. Studies investigating the timing of alcohol intoxication prior to trauma are limited, although there are two typical scenarios regarding alcohol consumption: Acute ('drink and drive scenario') and sub­acute ('evening binge drinking'). Therefore, the present study investigated the influence of either an acute or sub­acute alcohol­drinking scenario in an in vivo model of TxT and hemorrhagic shock, focusing on liver inflammation and outcomes. At 12 h (sub­acute) or 2 h (acute) before the experiment, female Lewis rats received a single oral dose of alcohol (ethanol, EtOH) or saline (NaCl, ctrl), followed by TxT, hemorrhagic shock (35±3 mm Hg) and resuscitation (H/R). The animals were either sacrificed 2 h later or their survival was determined for 72 h. The results revealed that EtOH induced significant fatty changes in the liver. TxT + H/R­induced increases in the gene expression of interleukin (IL)­6 and intercellular adhesion molecule­1 and the protein expression of tumor necrosis factor (TNF)­α and IL­1ß were significantly reduced in both EtOH groups compared with those in the corresponding TxT + H/R ctrl groups. The local presence of IL­10­expressing cells in the liver was significantly increased following TxT + H/R in all groups, although the sub­acute EtOH TxT + H/R group had a significantly higher proportion of IL­10­positive cells compared with all other groups. Stimulating peripheral whole blood with lipopolysaccharide led to significantly lower levels of TNF­α release in the sub­acute EtOH group compared with the levels in all other groups. Significant TxT + H/R­induced increases in liver transaminases and liver damage were most prominent in the sub­acute EtOH group. The TxT + H/R EtOH group exhibited the lowest levels of glucose. There were no significant differences in mortality rate among the TxT + H/R groups. The data obtained indicates that the severity of liver damage following TxT + H/R may depend on the timing of alcohol consumption and severity of trauma, but also on the balance between pro­ and anti­inflammatory responses.


Assuntos
Etanol/administração & dosagem , Hemorragia/complicações , Inflamação/etiologia , Inflamação/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Ferimentos e Lesões/complicações , Animais , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Inflamação/tratamento farmacológico , Inflamação/patologia , Metabolismo dos Lipídeos , Fígado/patologia , Ratos , Ratos Endogâmicos Lew
5.
Muscle Nerve ; 60(4): 437-442, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31325319

RESUMO

BACKGROUND: Reliable measurement of functional recovery is critical in translational peripheral nerve regeneration research. Behavioral functional assessments such as volitional grip strength testing (vGST) are limited by inherent behavioral variability. Isometric tetanic force testing (ITFT) is highly reliable but precludes serial measurements. Combining elements of vGST and ITFT, stimulated grip strength testing (sGST) involves percutaneous median nerve stimulation to elicit maximal tetanic contraction of digital flexors, thereby allowing for consistent measurement of maximal grip strength. METHODS: We measured side-to-side equivalence of force using sGST, vGST, and ITFT to determine relative reliability and repeatability. We also performed weekly force measurements following median nerve repair. RESULTS: sGST demonstrated greater reliability and inter-trial repeatability than vGST and similar reliability to ITFT, with the added benefit of serial measurements. CONCLUSIONS: sGST is a valid method for assessing functional recovery that addresses the limitations of the currently available modalities used in translational peripheral nerve regeneration research.


Assuntos
Força da Mão/fisiologia , Contração Isométrica/fisiologia , Nervo Mediano/fisiopatologia , Regeneração Nervosa , Recuperação de Função Fisiológica , Animais , Comportamento Animal , Estimulação Elétrica , Masculino , Nervo Mediano/lesões , Nervo Mediano/fisiologia , Nervo Mediano/cirurgia , Ratos , Ratos Endogâmicos Lew , Reprodutibilidade dos Testes , Nervo Ulnar/cirurgia
6.
Life Sci ; 233: 116666, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31325427

RESUMO

AIM: Pirfenidone (PFD) has been used as medication for idiopathic pulmonary fibrosis due to its ability in reducing lung fibrosis. However, the underlying mode of action in renal fibrosis during chronic renal allograft dysfunction (CRAD) requires further investigation. Therefore, the present study was conducted to explore the effects of PFD on renal injury induced by CRAD. MAIN METHODS: Initially, the CRAD rat model was established, followed by the intragastric administration of PFD to the rats. Urine and blood samples were collected and tested against indicators of renal functions. The renal tissues were microscopically observed to determine the changes in pathological morphology. The anti-inflammatory, anti-fibrotic and anti-oxidant properties of PFD were explored in the setting of CRAD. KEY FINDINGS: The success rate of model establishment was 92.31%, which was reflected by weight loss, appetite loss, faded fur, and retarded reaction, with the symptoms found to exacerbate with time. PFD treatment could improve renal function, ameliorate inflammation and renal fibrosis as well as promote the anti-oxidant ability of renal allograft, indicating its potential role as an effective therapeutic agent for CRAD. SIGNIFICANCE: In conclusion, PFD was found to have renoprotective effects on renal injury induced by CRAD, which resulted in the alleviation of inflammation and renal fibrosis, providing novelty for CRAD clinical treatment.


Assuntos
Fibrose/prevenção & controle , Rejeição de Enxerto/prevenção & controle , Transplante de Rim/efeitos adversos , Túbulos Renais/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Piridonas/farmacologia , Insuficiência Renal Crônica/cirurgia , Aloenxertos , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Doença Crônica , Fibrose/etiologia , Rejeição de Enxerto/etiologia , Túbulos Renais/patologia , Masculino , Ratos , Ratos Endogâmicos F344 , Ratos Endogâmicos Lew
7.
Br J Anaesth ; 123(4): 519-530, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31262508

RESUMO

BACKGROUND: Respiratory complications after surgery are associated with morbidity and mortality. Acute lung injury can result from the systemic inflammatory response after acute kidney injury. The mechanisms behind this remote injury are not fully understood. In this study, a renal transplantation model was used to investigate remote lung injury and the underlying molecular mechanisms, especially the role of osteopontin (OPN). METHODS: In vitro, human lung epithelial cell line (A549) and monocyte/macrophage cell line (U937) were challenged with tumour necrosis factor-alpha (TNF-α) in combination with OPN. In vivo, the Fischer rat renal grafts were extracted and stored in 4°C University of Wisconsin preserving solution for up to 16 h, and transplanted into Lewis rat recipients. Lungs were harvested on Day 1 after grafting for further analysis. RESULTS: Renal engraftment was associated with pathological changes and an increase in TNF-α and interleukin-1 beta in the lung of the recipient. OPN, endoplasmic reticulum (ER) stress, and necroptosis were increased in both the recipient lung and A549 cells challenged with TNF-α. Exogenous OPN exacerbated lung injury and necroptosis. Suppression of OPN through siRNA reduced remote lung injury by mitigation of ER stress, necroptosis, and the inflammatory response. CONCLUSIONS: Renal allograft transplant triggers recipient remote lung injury, which is, in part, mediated by OPN signalling. This study may provide a molecular basis for strategies to be developed to treat such perioperative complications.


Assuntos
Lesão Pulmonar Aguda/prevenção & controle , Transplante de Rim/efeitos adversos , Osteopontina/farmacologia , Complicações Pós-Operatórias/prevenção & controle , Animais , Apoptose , Células Cultivadas , Modelos Animais de Doenças , Humanos , Técnicas In Vitro , Masculino , Necrose , Ratos , Ratos Endogâmicos F344 , Ratos Endogâmicos Lew
8.
Transplant Proc ; 51(5): 1458-1462, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31155179

RESUMO

BACKGROUND: Subcutaneous pockets provide an extrahepatic transplant site for islet grafting to treat type 1 diabetes. However, a hypoxic environment may cause central necrosis to islets and lead to graft failure. Our previous studies focused on a pre-treated subcutaneous site with basic fibroblast growth factor (bFGF) for the formation of vascular bed. In addition to neovascularization, bFGF was also shown to protect islets against oxidative stress and chemical-induced damage in vitro. Accordingly, we propose that subcutaneous islet transplantation with a bFGF-slow releasing device simultaneously can improve islet survival in vivo. METHODS: A bFGF-impregnated collagen sheet was implanted in the right back of a streptozotocin-induced diabetic mouse for neovascularization. After 10 days, the sheet was removed and the rat islet-embedding gel within the immune-isolation device was transplanted (2-time operation [OP]). In another group, the diabetic mice received bFGF-impregnated gel with rat islets within the immune-isolation device simultaneously (1-time OP). RESULTS: Diabetic mice in 2-time OP group experienced a decrease in their non-fasting blood glucose level for a period of 10 days, and the glucose levels were lower than those of untreated diabetic mice post-implantation. However, the mice in the 1-time OP group remained hyperglycemic post-operation and showed no improvements in body weight or the area under curve in intraperitoneal glucose tolerance test. Furthermore, mice in the 2-time OP had relatively higher serum insulin levels with improved renal and metabolic biomarkers. CONCLUSION: Our findings suggest that bFGF had no beneficial effect on a 1-time operation in subcutaneous islet transplantation.


Assuntos
Diabetes Mellitus Experimental/cirurgia , Fator 2 de Crescimento de Fibroblastos/administração & dosagem , Transplante das Ilhotas Pancreáticas/instrumentação , Transplante das Ilhotas Pancreáticas/métodos , Tela Subcutânea , Animais , Glicemia , Diabetes Mellitus Experimental/metabolismo , Modelos Animais de Doenças , Xenoenxertos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neovascularização Fisiológica/efeitos dos fármacos , Ratos , Ratos Endogâmicos Lew , Tela Subcutânea/cirurgia
9.
PLoS Pathog ; 15(6): e1007833, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31220182

RESUMO

Rift Valley fever virus (RVFV) causes severe disease in livestock concurrent with zoonotic transmission to humans. A subset of people infected with RVFV develop encephalitis, and significant gaps remain in our knowledge of how RVFV causes pathology in the brain. We previously found that, in Lewis rats, subcutaneous inoculation with RVFV resulted in subclinical disease while inhalation of RVFV in a small particle aerosol caused fatal encephalitis. Here, we compared the disease course of RVFV in Lewis rats after each different route of inoculation in order to understand more about pathogenic mechanisms of fatal RVFV encephalitis. In aerosol-infected rats with lethal encephalitis, neutrophils and macrophages were the major cell types infiltrating the CNS, and this was concomitant with microglia activation and extensive cytokine inflammation. Despite this, prevention of neutrophil infiltration into the brain did not ameliorate disease. Unexpectedly, in subcutaneously-inoculated rats with subclinical disease, detectable viral RNA was found in the brain along with T-cell infiltration. This study sheds new light on the pathogenic mechanisms of RVFV encephalitis.


Assuntos
Encéfalo/imunologia , Encefalite Viral/imunologia , Macrófagos/imunologia , Infiltração de Neutrófilos , Neutrófilos/imunologia , Febre do Vale de Rift/imunologia , Vírus da Febre do Vale do Rift/imunologia , Aerossóis , Animais , Encéfalo/patologia , Encéfalo/virologia , Linhagem Celular , Citocinas/imunologia , Encefalite Viral/patologia , Feminino , Humanos , Macrófagos/patologia , Neutrófilos/patologia , Ratos , Ratos Endogâmicos Lew , Febre do Vale de Rift/patologia
10.
Transpl Immunol ; 55: 101211, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31247293

RESUMO

OBJECTIVES: The various forms of chronic rejection share a common histological appearance termed allograft arteriosclerosis. In the early stages thereof, apoptosis of vascular smooth muscle cells (VSMC) is obviously reduced, associated with vascular intimal thickening. High-level expression of the HSG/Mfn2 gene promotes apoptosis of rat VSMC. However, the role and mechanism of Mfn2 in inhibition of chronic allograft rejection have not been described. METHODS: In the present study, we transfected transplanted abdominal aortas of donor Lewis rats with an Mfn2-encoding or control lentivirus. And then We transplanted the donor aortas to the corresponding aortal positions in recipient rats. Transplanted aortas were collected on days 30, 60, and 90 and Masson stained to measure intimal thicknesses. Immunohistochemistry would be used to confirm TGF-ß1, Mfn2 and TGF-ß-R2 expression in different groups. RESULTS: Our results confirm that high-level expression of Mfn2 lowers the expression of TGF-ß1, reduces the intimal thickness of transplanted rat abdominal aorta, and retards the process of chronic rejection. CONCLUSION: Mfn2 influences TGF-ß/smad pathway and may function as potential chronic rejection inhibitor.


Assuntos
Aorta Abdominal , Arteriosclerose , Rejeição de Enxerto , Proteínas de Membrana/imunologia , Proteínas Mitocondriais/imunologia , Transdução de Sinais/imunologia , Fator de Crescimento Transformador beta1/imunologia , Animais , Aorta Abdominal/imunologia , Aorta Abdominal/patologia , Aorta Abdominal/transplante , Arteriosclerose/imunologia , Arteriosclerose/patologia , Doença Crônica , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/patologia , Masculino , Ratos , Ratos Endogâmicos Lew , Transplante Homólogo
11.
Eur Surg Res ; 60(1-2): 63-73, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31055575

RESUMO

BACKGROUND: It was demonstrated that polyamines ameliorate ischemia-reperfusion injury (IRI) and promote regeneration in the liver. An optimal protocol of polyamine treatment remains unknown in the clinical setting. We examined 2 types of administration methods using rat models. METHODS: Experiment 1: evaluation of pharmacokinetics of polyamines. Experiment 2: for 3 days preoperatively and 5 days postoperatively, polyamines were given to male Lewis rats in the following three groups: the control group, no polyamine administration; the chow group, 0.05% polyamines mixed in chow; the bolus group, polyamines (200 µmol/kg) given by gastric tube once a day. All rats received 70% hepatectomy after 40 min of warm IRI. Postoperatively, IRI and regeneration were evaluated with assessment of serum levels of hepatic enzymes, histology and immunohistochemistry of liver tissue, and measurement of remnant liver weight. RESULTS: The blood concentrations of polyamines in the portal vein increased at 1 h of bolus administration, while they did not increase without the bolus. The bolus group was significantly associated with lower serum levels of aspartate/alanine aminotransferases (p < 0.05), decreased hepatocyte congestion, vacuolization and necrosis in histopathological scoring (p < 0.05), a lower number of TUNEL-positive hepatocytes (p < 0.05), higher remnant liver weight at 24, 48, and 168 h (p < 0.05), and a higher Ki-67 labeling index (24 h, p < 0.01) compared with the chow group. CONCLUSION: The bolus administration of polyamines was more effective in ameliorating IRI and promoting regeneration than chow administration. Perioperative bolus administration of polyamines might be an optimal treatment, when clinically applied.


Assuntos
Regeneração Hepática/efeitos dos fármacos , Fígado/irrigação sanguínea , Poliaminas/farmacologia , Traumatismo por Reperfusão/prevenção & controle , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Antígeno Ki-67/análise , Fígado/patologia , Masculino , Ratos , Ratos Endogâmicos Lew
12.
BMC Surg ; 18(Suppl 1): 126, 2019 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-31074398

RESUMO

BACKGROUND: Islet transplantation has progressively become a safe alternative to pancreas transplantation for the treatment of type 1 diabetes. However, the long-term results of islet transplantation could be significantly increased by improving the quality of the islet isolation technique even exploring alternative islet transplantation sites to reduce the number of islets required to mitigate hyperglycemia. The goal of the study was to test the lymph node as a suitable anatomical location for islet engraftment in a rodent model. METHODS: Forty Lewis rats, 6-8 weeks old, body weight 250-300 g, have been used as islet donors and recipients in syngeneic islet transplantation experiments. Ten rats were rendered diabetic by one injection of 65 mg/Kg of streptozotocin. After pancreas retrieval from non diabetic donors, islet were isolated and transplanted in the mesenteric lymph nodes of 7 diabetic rats. Rats were followed for 30 days after islet transplantation. RESULTS: A total of 7 islet transplantations in mesenteric lymph nodes have been performed. Two rats died 24 and 36 h after transplantation due to complications. No transplanted rat acquired normal glucose blood levels and insulin independence after the transplantation. However, the mean blood levels of glycemia were significantly lower in transplanted rats compared with diabetic rats (470.4 mg/dl vs 605 mg/dl, p 0.04). Interestingly, transplanted rats have a significant weight increase after transplantation compared to diabetic rats (mean value 295 g in transplanted rats vs 245 g in diabetic rats, p < 0.05), with an overall improvement of social activities and health. Immunohistochemical analysis of the 5 mesenteric lymph nodes of transplanted rats demonstrated the presence of living islets in one lymph node. CONCLUSIONS: Although islet engraftment in lymph nodes is possible, islet transplantation in lymph nodes in rats resulted in few improvements of glucose parameters.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus Experimental/terapia , Transplante das Ilhotas Pancreáticas/métodos , Animais , Insulina/metabolismo , Linfonodos , Masculino , Pâncreas/patologia , Transplante de Pâncreas/métodos , Ratos , Ratos Endogâmicos Lew
13.
PLoS One ; 14(5): e0216136, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31075114

RESUMO

BACKGROUND: Optimizing the collagenase G (ColG):collagenase H (ColH) ratio is a key strategy for achieving tailored donor-tissue specific islet isolation. Collagen V (Col V) and collagen III (Col III) are crucial target matrices of ColG and ColH, respectively. We herein investigated the relevance between the expression of target matrices in pancreatic tissues and influence of ColG:ColH ratio on islet isolation outcome. METHODS: Islet isolation was performed in Lewis and SD rats using different ColG:ColH ratios (5:1, 1:1 and 1:5; n = 7/group). The composition of Col III and Col V was examined using immunohistochemical staining, real-time polymerase chain reaction (PCR), Western blotting and mass spectrometry. Chain types in collagen I (Col I) were also assessed using mass spectrometry. RESULTS: No beneficial effects were observed by increasing the ColG amount, irrespective of the rat strain. In contrast, the islet yield in Lewis rats was considerably increased by high amounts of ColH but decreased in SD rats, suggesting that Lewis pancreas contains more Col III than SD pancreas. Neither immunohistochemical nor real-time PCR showed correlation with isolation outcome. However, Western blotting revealed that Lewis contained considerably higher amount of Col III than SD (p = 0.10). Likewise, Col-I(α1)/Col-III(α1) and Col-I(α2)/Col-III(α1) were significantly lower in Lewis than in SD rats (p = 0.007, respectively). Furthermore, the isolation outcome was considerably correlated with the composition of homotrimeric Col I. CONCLUSIONS: The Col III expression and the composition of homotrimeric Col I in pancreatic tissues determined using mass analyses appeared useful for optimizing the ColG:ColH ratio in islet isolation.


Assuntos
Ilhotas Pancreáticas/citologia , Animais , Colágeno/metabolismo , Colagenases/metabolismo , Ilhotas Pancreáticas/metabolismo , Transplante das Ilhotas Pancreáticas/métodos , Ratos , Ratos Endogâmicos Lew , Ratos Sprague-Dawley , Doadores de Tecidos
14.
J Bone Joint Surg Am ; 101(10): e42, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31094986

RESUMO

BACKGROUND: Nerve injuries with a gap/defect represent a clinical challenge without a clear solution. Reconstruction with cable autografts is a common treatment technique, and repair with decellular nerve allograft is a newer option. The purpose of this study was to compare the functional outcomes of reconstruction with cable autografts with those of matched-diameter decellular nerve allografts to evaluate the relative importance of diameter as well as the autograft-versus-allograft nature of the reconstruction. METHODS: A unilateral 10-mm sciatic nerve defect was created in 81 genetically identical male Lewis rats and then repaired with a reverse autograft, 4 or 5 sural nerve cable autografts, or a matched-diameter decellular nerve allograft. In each group, at each time point (12, 16, and 20 weeks), all 9 animals underwent functional testing and 5 of the 9 underwent histologic analysis. Functional testing included bilateral measurements of the isometric tetanic force of the tibialis anterior (primary outcome), the weight of the tibialis anterior, and the gastrocnemius compound muscle action potential (CMAP) latency. Histologic evaluation included an axon count as well as measurement of the axon density, fiber diameter, myelin thickness, and G-ratio. RESULTS: The repair groups did not differ significantly in terms of isometric tetanic force, muscle weight, or CMAP latency, but these measurements did differ significantly according to the time after surgery (p < 0.05). The isometric tetanic force percent recovery (width of the 95% confidence interval) for the reverse autograft, cable autograft, and decellular nerve allograft was 57.7% (15.6%), 57.0% (23.4%), and 56.0% (19.7%), respectively, at 12 weeks; 69.1% (14.7%), 65.6% (18.5%), and 65.9% (29.1%) at 16 weeks; and 72.5% (18.2%), 73.7% (25.6%), and 71.8% (22.4%) at 20 weeks. Isometric tetanic force and muscle weight recovery were greater and CMAP latency was shorter at 20 and 16 weeks after surgery than they were at 12 weeks. The treatment type did not affect any of the histologic outcomes. CONCLUSIONS: In this animal study, we found that matched-diameter decellular nerve allograft was not significantly different from reverse autograft or cable graft reconstruction in terms of function and histologic outcomes. These findings support decellular nerve allograft as a viable treatment option for nerve reconstruction. CLINICAL RELEVANCE: This study showed that decellular nerve allograft was no different from cable or reverse autograft in terms of outcome measures in a rat sciatic nerve defect model. If these results are applicable clinically, it would obviate the need for autograft nerve harvest and its ensuing donor site morbidity.


Assuntos
Aloenxertos/transplante , Autoenxertos/transplante , Procedimentos Neurocirúrgicos/métodos , Traumatismos dos Nervos Periféricos/cirurgia , Nervo Isquiático/lesões , Animais , Masculino , Regeneração Nervosa , Ratos , Ratos Endogâmicos Lew , Ratos Sprague-Dawley , Recuperação de Função Fisiológica , Nervo Isquiático/cirurgia , Nervo Isquiático/transplante , Nervo Sural/transplante , Transplante Autólogo/métodos , Transplante Homólogo/métodos , Resultado do Tratamento
15.
Artigo em Inglês | MEDLINE | ID: mdl-31119105

RESUMO

Toxoplasmosis is considered as an opportunistic parasitic disease. If post-natally acquired in children or adults, it may pass unnoticed, at least with strains of European origin. However, in the wild biotopes especially in South America, Toxoplasma gondii strains display a greater genetic diversity, which correlates to higher virulence for humans, particularly along the Amazon River and its tributaries. In French Guiana, several atypical strains have been associated with severe clinical forms: ocular toxoplasmosis and acute respiratory distress syndrome both of which can result in death. Among these, the GUY008-ABE strain was responsible for an epidemic of severe disseminated toxoplasmosis in Suriname, which led to the death of one immunocompetent individual. To better understand the mechanism underlying the hypervirulence of the GUY008-ABE strain, we have tested the rat model which compared to the mouse, better reflects the immune resistance of humans to Toxoplasma infection. Here we compare the outcome of toxoplasmosis in F344 rats infected either by the GUY008-ABE strain or the type II Prugniaud strain. We show that the GUY008-ABE strain displays a higher virulence phenotype leading to the death of all infected rats observed in this study. GUY008-ABE infection was characterized by an increase of the parasite load in several organs, especially the heart and lung, and was mainly associated with severe histological changes in lungs. Moreover, correlating with its hypervirulence trait, the GUY008-ABE strain was able to form cysts in the LEW rat model otherwise known to be refractory to infection by other Toxoplasma strains. Together, these results show that the rat is a discriminating experimental model to study Toxoplasma virulence factors relevant to the pathogenesis of human infection and that the degree of virulence is linked to the Toxo1 locus.


Assuntos
Modelos Animais de Doenças , Toxoplasma/patogenicidade , Toxoplasmose Animal/patologia , Toxoplasmose Animal/parasitologia , Estruturas Animais/parasitologia , Animais , Carga Parasitária , Ratos Endogâmicos F344 , Ratos Endogâmicos Lew , Análise de Sobrevida , Toxoplasma/crescimento & desenvolvimento , Virulência
16.
Life Sci ; 230: 84-88, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31128137

RESUMO

INTRODUCTION: Exercise programs have been shown to be effective for both reducing risk for, and intervention following, substance abuse behaviors in both clinical and preclinical studies. Less is known, however, regarding the underlying neurobiological substrates involved in these changes in drug seeking behavior. In this study, we assessed cannabinoid receptor (CB1) levels throughout the brain which are key in endocannabinoid signaling following chronic aerobic exercise. METHODS: Male and female Lewis young adult rats were grouped into exercise and sedentary groups at 8 weeks of age. Exercise rats ran on a treadmill at 10 m/min, 5 days/week, for 6 weeks, whereas sedentary rats remained in their home cage. Rats were euthanized after 6 weeks, and in vitro receptor autoradiography was performed using [3H] SR141716A to quantify CB1 receptors throughout the brain. RESULTS: Exercise rats did not show significantly different [3H] SR141716A binding levels as compared to sedentary rats; however, an overall sex effect was found, where males had 29% higher [3H] SR141716A binding within the pyramidal layer of the hippocampus when compared to females. The chronic aerobic exercise regimen did not produce any changes in CB1 receptor levels. CONCLUSIONS: The present study found that chronic exercise during young adulthood did not alter cannabinoid CB1 receptor levels in the brain. Therefore, previously reported decreased cocaine preference in parallel treated cohorts did not involve exercise induced changes in CB1 levels which is key for endocannabinoid signaling.


Assuntos
Condicionamento Físico Animal/fisiologia , Receptor CB1 de Canabinoide/efeitos dos fármacos , Receptor CB1 de Canabinoide/fisiologia , Animais , Autorradiografia , Encéfalo/metabolismo , Endocanabinoides/metabolismo , Endocanabinoides/fisiologia , Feminino , Hipocampo/metabolismo , Masculino , Ratos , Ratos Endogâmicos Lew , Fatores Sexuais
17.
Eur J Pharm Biopharm ; 142: 20-30, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31129274

RESUMO

Electrospinning technique has been explored to produce nanofibers incorporated with drugs as alternative drug delivery systems for therapeutic purposes in various organs and tissues. Before such systems could potentially be used, their biocompatibility must be evaluated. In this study, dexamethasone acetate-loaded poly(ɛ-caprolactone) nanofibers (DX PCL nanofibers) were developed for targeted delivery in the vitreous cavity in the treatment of retinal diseases. Ocular biocompatibility was tested in vitro and in vivo. DX PCL nanofibers were characterized by scanning electron microscopy (SEM) and Fourier Transform InfraRed spectroscopy (FTIR) and the in vitro drug release from nanofibers was evaluated. The in vitro biocompatibility of DX PCL nanofibers was tested on both ARPE-19 and MIO-M1 cells using the cytotoxicity (MTT) test by morphological studies based on staining of the actin fibers in ARPE-19 cells and GFAP in MIO-M1 cells. The in vivo biocompatibility of DX PCL nanofibers was investigated after intravitreous injection in the rat eye, using spectral domain Optical Coherence Tomography (OCT) imaging of the retina. SEM results indicated that nanometric fibers were interconnected in a complex network, and that they were composed of polymer. FTIR showed that polymer and drug did not chemically interact after the application of the electrospinning technique. PCL nanofibers provided controlled DX release for 10 days. DX PCL nanofibers were not cytotoxic to the ocular cells, allowing for the preservation of actin fibers and GFAP in the cytoplasm of ARPE-19 and MIO-M1 cells, respectively, which are biomarkers of these ocular cell populations. DX PCL nanofibers did not affect the retinal and choroidal structures, and they did not induce abnormalities, hemorrhages, or retinal detachment, suggesting that the nanofibers were well tolerated. In eyes receiving DX PCL nanofibers, SD-OCT images were corroborated with histological analysis of neuroretina and choroid, which are ocular tissues that are extremely sensitive to toxic agents. Finally, the preservation of cone and rod photoreceptors indicated the light sensitivity of the animals. In conclusion, DX PCL nanofibers exhibited ocular biocompatibility and safety in the rodent eye and allow the release of dexamethasone. Further studies are required to appreciate the potential of these new drug delivery systems for the treatment of retinal diseases.


Assuntos
Dexametasona/administração & dosagem , Dexametasona/química , Nanofibras/administração & dosagem , Nanofibras/química , Poliésteres/química , Retina/efeitos dos fármacos , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos/efeitos dos fármacos , Feminino , Humanos , Ratos , Ratos Endogâmicos Lew , Doenças Retinianas/tratamento farmacológico , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Engenharia Tecidual/métodos , Tecidos Suporte
18.
J Neuroinflammation ; 16(1): 73, 2019 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-30953561

RESUMO

BACKGROUND: Autoantibodies against the paranodal protein contactin-1 have recently been described in patients with severe acute-onset autoimmune neuropathies and mainly belong to the IgG4 subclass that does not activate complement. IgG3 anti-contactin-1 autoantibodies are rare, but have been detected during the acute onset of disease in some cases. There is evidence that anti-contactin-1 prevents adhesive interaction, and chronic exposure to anti-contactin-1 IgG4 leads to structural changes at the nodes accompanied by neuropathic symptoms. However, the pathomechanism of acute onset of disease and the pathogenic role of IgG3 anti-contactin-1 is largely unknown. METHODS: In the present study, we aimed to model acute autoantibody exposure by intraneural injection of IgG of patients with anti-contacin-1 autoantibodies to Lewis rats. Patient IgG obtained during acute onset of disease (IgG3 predominant) and IgG from the chronic phase of disease (IgG4 predominant) were studied in comparison. RESULTS: Conduction blocks were measured in rats injected with the "acute" IgG more often than after injection of "chronic" IgG (83.3% versus 35%) and proved to be reversible within a week after injection. Impaired nerve conduction was accompanied by motor deficits in rats after injection of the "acute" IgG but only minor structural changes of the nodes. Paranodal complement deposition was detected after injection of the "acute IgG". We did not detect any inflammatory infiltrates, arguing against an inflammatory cascade as cause of damage to the nerve. We also did not observe dispersion of paranodal proteins or sodium channels to the juxtaparanodes as seen in patients after chronic exposure to anti-contactin-1. CONCLUSIONS: Our data suggest that anti-contactin-1 IgG3 induces an acute conduction block that is most probably mediated by autoantibody binding and subsequent complement deposition and may account for acute onset of disease in these patients. This supports the notion of anti-contactin-1-associated neuropathy as a paranodopathy with the nodes of Ranvier as the site of pathogenesis.


Assuntos
Contactina 1/imunologia , Síndrome de Guillain-Barré/complicações , Imunização Passiva/métodos , Imunoglobulina G/farmacologia , Transtornos Motores/fisiopatologia , Transtornos Motores/cirurgia , Animais , Moléculas de Adesão Celular Neuronais/metabolismo , Complemento C1q/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Síndrome de Guillain-Barré/etiologia , Humanos , Transtornos Motores/induzido quimicamente , Condução Nervosa/efeitos dos fármacos , Neurite Óptica/sangue , Neurite Óptica/imunologia , Nós Neurofibrosos/efeitos dos fármacos , Nós Neurofibrosos/metabolismo , Ratos , Ratos Endogâmicos Lew , Tempo de Reação/efeitos dos fármacos , Recuperação de Função Fisiológica/efeitos dos fármacos , Teste de Desempenho do Rota-Rod , Estatísticas não Paramétricas
19.
Life Sci ; 227: 51-57, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-31004655

RESUMO

AIMS: Increasing evidence has shown the diagnostic value of miR-155 in organ transplantation. The dysregulation of miR-155 is reported to be associated with development of acute or chronic complications in solid organ transplant recipients. Here, we summarized related evidence to explore the correlation between the dysregulation of miR-155 and various allograft dysfunction in transplant recipients, and verified the dynamic change of miR-155 level in acute rejection (AR) using a rat renal transplantation model. MAIN METHODS: Eligible studies were retrieved from PubMed, Embase, and Cochrane Library databases. A meta-analysis method was performed to evaluate the diagnostic value of miR-155 in transplant recipients. Furthermore, the F344-Lewis rat renal transplantation model was established to validate the dynamic change of miR-155 expression during AR. KEY FINDINGS: A total of 275 transplant patients, including renal, heart, and lung transplantation from 6 studies were analysed. The pooled SEN of miR-155 was 0.87 (95% CI, 0.78-0.93), the pooled SPE was 0.76 (95% CI, 0.63-0.85), the pooled PLR was 3.6 (95% CI, 2.2-5.8), the pooled NLR was 0.17 (95% CI, 0.09-0.31), the pooled DOR was 17.31 (95% CI, 7.20-41.65) and pooled AUC was 0.89 (95% CI, 0.86-0.92). The rat renal transplantation model (n = 24) and control model (n = 15) were successfully established. Expression of miR-155 in plasma was significantly increased in 7 d and 9 d post-transplantation compared to the control group (P < 0.05), and was consistent with the dynamic change of AR degree. SIGNIFICANCE: miR-155 is a potential biomarker for monitoring the abnormal allograft status in solid organ transplantation.


Assuntos
Rejeição de Enxerto/genética , MicroRNAs/genética , Aloenxertos/fisiologia , Animais , Biomarcadores/sangue , Humanos , Rim/fisiologia , Transplante de Rim/métodos , Masculino , MicroRNAs/sangue , MicroRNAs/fisiologia , Modelos Animais , Curva ROC , Ratos , Ratos Endogâmicos F344 , Ratos Endogâmicos Lew , Transplante Homólogo/métodos
20.
Toxicol Pathol ; 47(4): 542-552, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30987532

RESUMO

Experimental autoimmune neuritis (EAN) is an animal model for Guillain-Barré syndrome (GBS), which results in neurological symptoms and histopathological changes in peripheral nerves. In this model, the correlation between the progression of the disease and the histopathological changes is not clear. To further examine histopathological changes in peripheral nerves in EAN rats, sciatic nerves were sampled at onset (day 10), peak (day 16), and recovery (days 22 and 25) of neurological symptoms in P2(57-81)-peptide-administered rats. Axon and myelin degeneration was observed by light microscopy at onset, degeneration became severe at peak, and persisted at recovery. Densities of myelinated nerve fibers and myelin areas decreased from day 10 to a minimum on day 22. Slight axon and myelin degeneration, such as accumulation of vesicles in axons and focal myelin splitting and folding, was observed by transmission electron microscopy at onset; severe degeneration, such as axonal loss, myelin ovoid, and demyelination, increased at peak; and regenerative changes, such as remyelination and enlargement of Schwann cell cytoplasm, occurred at recovery. These results suggest that EAN rats have histopathological similarities to some types of GBS patients and that EAN rats are a useful model to understand the pathogenesis of GBS.


Assuntos
Axônios/ultraestrutura , Síndrome de Guillain-Barré/patologia , Bainha de Mielina/ultraestrutura , Neurite Autoimune Experimental/patologia , Nervo Isquiático/patologia , Animais , Síndrome de Guillain-Barré/imunologia , Masculino , Microscopia Eletrônica de Transmissão , Proteína P2 de Mielina/imunologia , Fibras Nervosas Mielinizadas/ultraestrutura , Neurite Autoimune Experimental/imunologia , Fragmentos de Peptídeos/imunologia , Ratos Endogâmicos Lew
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