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1.
Zootaxa ; 5410(4): 586-598, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38480222

RESUMO

Two new armoured scale insect species (Hemiptera: Coccomorpha: Diaspididae) are described and illustrated from Guizhou Province, China. Aulacaspis pericampylus sp. n. was collected from Pericampylus glaucus (Menispermaceae) and Aulacaspis multispinata sp. n. was collected from Cinnamomum camphora (Lauraceae). The type specimens of both new species are deposited in the Institute of Entomology, Guizhou University, Guiyang, China (GUGC). A key to the Aulacaspis species known from China, based on the morphology of the adult females, is provided.


Assuntos
Hemípteros , Lauraceae , Humanos , Feminino , Animais , Hemípteros/anatomia & histologia , China , Universidades
2.
J Virol Methods ; 327: 114921, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38552881

RESUMO

Dendritic cells (DCs) play a pivotal role in maintaining immune tolerance. Using recombinant adenovirus (rAd) to deliver vectors to immature dendritic cells (imDCs) is an important method for studying the tolerogenic function of DCs. We found that using RPMI medium and a higher MOI during transduction increased the expression of CD80, CD86, and MHC-II on the surface of imDCs. Our data reveal a significant increase in the secretion of the pro-inflammatory cytokine IL-6 in the group showing the most pronounced phenotypic changes. In the mouse heart transplant model, imDCs with unstable phenotype and function due to adenoviral transduction resulted in an increased proportion of Th1 and Th17 cells in recipients. However, these effects can be managed, and our proposed optimized transduction strategy significantly minimizes these adverse effects. Our study holds significant implications for the development and optimization of immunotherapy utilizing tolerogenic dendritic cells.


Assuntos
Adenoviridae , Células Dendríticas , Vetores Genéticos , Imunoterapia , Transdução Genética , Células Dendríticas/imunologia , Animais , Adenoviridae/genética , Camundongos , Imunoterapia/métodos , Vetores Genéticos/genética , Transplante de Coração , Camundongos Endogâmicos C57BL , Interleucina-6/metabolismo , Tolerância Imunológica , Antígeno B7-1/genética , Antígeno B7-1/metabolismo , Células Th1/imunologia , Células Th17/imunologia , Antígeno B7-2/metabolismo , Antígeno B7-2/genética
3.
Zootaxa ; 5285(3): 571-577, 2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37518690

RESUMO

A new species of armoured scale insect, Formosaspis fanjingensis sp. n. (Hemiptera: Coccomorpha: Diaspididae), is described; it was found on Chimonobambusa spp. (Poaceae; Bambusoideae) in Guizhou Province, China. Habitat photographs and taxonomic illustrations are provided. The type specimens are deposited at the Institute of Entomology, Guizhou University, Guiyang, China (GUGC). An identification key based on the morphology of adult females is provided to separate all the species in the genus.


Assuntos
Hemípteros , Humanos , Feminino , Animais , China , Universidades , Poaceae
4.
Dig Dis ; 41(6): 938-945, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37494918

RESUMO

INTRODUCTION: The aim of the study was to investigate the relationship between systemic immune-inflammation index (SII) and early allograft dysfunction (EAD) and 90-day mortality after liver transplantation (LT) in acute-on-chronic liver failure (ACLF). METHODS: Retrospective record analysis was done on 114 patients who had LT for ACLF. To identify the ideal SII, the receiver operating characteristic curve was used. The incidence of EAD and 90-day mortality following LT were calculated. The prognostic value of SII was assessed using the Kaplan-Meier technique and the Cox proportional hazards model. RESULTS: The cut-off for SII was 201.5 (AUC = 0.728, p < 0.001). EAD occurred in 40 (35.1%) patients of the high SII group and 5 (4.4%) patients of the normal SII group, p < 0.001. 18 (15.8%) deaths occurred in the high SII group and 2 (1.8%) deaths occurred in the normal SII group, p = 0.008. The multivariate analysis demonstrated that SII ≥201.5, MELD ≥27 were independent prognostic factors for 90-day mortality after LT. CONCLUSION: SII predicts the occurrence of EAD and is an independent risk factor for 90-day mortality after LT.


Assuntos
Insuficiência Hepática Crônica Agudizada , Transplante de Fígado , Humanos , Transplante de Fígado/efeitos adversos , Insuficiência Hepática Crônica Agudizada/diagnóstico , Insuficiência Hepática Crônica Agudizada/etiologia , Insuficiência Hepática Crônica Agudizada/cirurgia , Estudos Retrospectivos , Inflamação , Prognóstico , Aloenxertos
5.
Front Immunol ; 14: 1182851, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37197662

RESUMO

Introduction: Central to allograft rejection is the T cell-mediated adaptive immune response initiated by activated dendritic cells (DCs). Previous studies have shown that the DNA-dependent activator of IFN regulatory factors (DAI) is involved in the maturation and activation of DCs. Therefore, we hypothesized that inhibition of DAI could prevent DCs from maturation and prolong murine allograft survival. Methods: Donor mouse bone marrow-derived dendritic cells (BMDCs) were transduced with the recombinant adenovirus vector (AdV-DAI-RNAi-GFP) to inhibit DAI expression (DC-DAI-RNAi), and the immune cell phenotype and function of DC-DAI-RNAi upon lipopolysaccharide (LPS) stimulation were evaluated. Then DC-DAI-RNAi was injected into recipient mice before islet transplantation and skin transplantation. The survival times of islet and skin allograft were recorded and the proportions of T cell subsets in spleen and secretion levels of cytokines in serum were measured. Results: We identified that DC-DAI-RNAi inhibited the expression of main co-stimulatory molecules and MHC-II, exhibited strong phagocytic ability, and secreted high levels of immunosuppressive cytokines and low levels of immunostimulating cytokines. Recipient mice treated with DC-DAI-RNAi had longer islet and skin allograft survival times. In the murine islet transplantation model, we observed an increase in Treg cells proportion, a reduction in Th1 and Th17 cells proportions in spleen, and similar trends in their secreted cytokines in serum in the DC-DAI-RNAi group. Conclusion: Inhibition of DAI by adenovirus transduction inhibits the maturation and activation of DCs, affects the differentiation of T cell subsets as well as their secreted cytokines, and prolongs allograft survival.


Assuntos
Citocinas , Linfócitos T Reguladores , Animais , Camundongos , Aloenxertos , Citocinas/metabolismo , Células Dendríticas , Transplante Homólogo
6.
Front Immunol ; 14: 1034356, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36845083

RESUMO

Introduction: The risk of alcoholic cirrhosis increases in a dose- and time-dependent manner with alcohol consumption and ethanol metabolism in the liver. Currently, no effective antifibrotic therapies are available. We aimed to obtain a better understanding of the cellular and molecular mechanisms involved in the pathogenesis of liver cirrhosis. Methods: We performed single-cell RNA-sequencing to analyze immune cells from the liver tissue and peripheral blood form patients with alcoholic cirrhosis and healthy controls to profile the transcriptomes of more than 100,000 single human cells and yield molecular definitions for non-parenchymal cell types. In addition, we performed single-cell RNA-sequencing analysis to reveal the immune microenvironment related to alcoholic liver cirrhosis. Hematoxylin and eosin, Immunofluorescence staining and Flow cytometric analysis were employed to study the difference between tissues and cells with or without alcoholic cirrhosis. Results: We identified a fibrosis-associated M1 subpopulation of macrophages that expands in liver fibrosis, differentiates from circulating monocytes, and is pro-fibrogenic. We also define mucosal-associated invariant T (MAIT) cells that expand in alcoholic cirrhosis and are topographically restricted to the fibrotic niche. Multilineage modeling of ligand and receptor interactions between the fibrosis-associated macrophages, MAIT, and NK cells revealed the intra-fibrotic activity of several pro-fibrogenic pathways, including responses to cytokines and antigen processing and presentation, natural killer cell-mediated cytotoxicity, cell adhesion molecules, Th1/Th2/Th17 cell differentiation, IL-17 signaling pathway, and Toll-like receptor signaling pathway. Discussion: Our work dissects unanticipated aspects of the cellular and molecular basis of human organ alcoholic fibrosis at the single-cell level and provides a conceptual framework for the discovery of rational therapeutic targets in liver alcoholic cirrhosis.


Assuntos
Cirrose Hepática Alcoólica , Cirrose Hepática , Humanos , Cirrose Hepática Alcoólica/patologia , Citocinas , Macrófagos
7.
Dig Dis ; 41(2): 250-258, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35753308

RESUMO

BACKGROUND: Partial liver transplantation has recently been proposed to alleviate organ shortages. However, transplantation of a small-for-size graft is associated with an increased risk of posttransplant hepatic dysfunction, commonly referred to as small-for-size syndrome (SFSS). This review describes the etiology, pathological features, clinical manifestations, and diagnostic criteria of SFSS. Moreover, we summarize strategies to improve graft function, focusing on graft inflow modulation techniques. Finally, unmet needs and future perspectives are discussed. SUMMARY: In fact, posttransplant SFSS can be attributed to various factors such as preoperative status of the recipients, surgical techniques, donor age, and graft quality, except for graft size. With targeted improvement measures, satisfactory clinical outcomes can be achieved in recipients at increased risk of SFSS. Given the critical role of relative portal hyperperfusion in the pathogenesis of SFSS, various pharmacological and surgical treatments have been established to reduce or partially divert excessive portal inflow, and recipients will benefit from individualized therapeutic regimens after careful evaluation of benefits against potential risks. However, there remain unmet needs for further research into different aspects of SFSS to better understand the correlation between portal hemodynamics and patient outcomes. KEY MESSAGES: Contemporary transplant surgeons should consider various donor and recipient factors and develop case-specific prevention and treatment strategies to improve graft and recipient survival rates.


Assuntos
Hepatopatias , Transplante de Fígado , Humanos , Transplante de Fígado/efeitos adversos , Transplante de Fígado/métodos , Doadores de Tecidos , Hemodinâmica , Fígado , Tamanho do Órgão , Sobrevivência de Enxerto
8.
Surg Infect (Larchmt) ; 23(9): 848-856, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36269593

RESUMO

Background: Parvovirus B19 (B19V) infection is a rare cause of severe anemia in liver transplant recipients. However, few studies have systematically reviewed reported cases and summarized experience in managing this disease. Objective: We described a retrospective case series of eight adult liver transplant recipients with B19V-associated severe anemia and performed a literature review of epidemiology, etiology, clinical courses, diagnosis, treatment options available, and outcomes of B19V-associated anemia in adult liver transplant recipients. Patients and Methods: We systematically reviewed articles describing adult liver transplant recipients with B19V-associated anemia from PubMed and ScienceDirect databases from database inception to May 2022. Results: Eight articles containing 23 cases were identified in addition to eight cases from our center for a total of 31 patients (mean age, 45.7 ± 9.7 years; 74.2% male). Eighty-seven percent developed transfusion-dependent anemia within two months after liver transplantation (LT). Fever and progressive anemia are among the major manifestations. Intravenous immunoglobulin (IVIG)-based therapy was given to all patients and the treatment protocols varied among different centers. Except for two cases who died of comorbidities, 17 patients obtained long-term recovery from anemia after one course of treatment and six (19%) experienced relapses that were reversed by repeated courses of IVIG therapy. Two recipients presented with IVIG-associated side effects and two developed acute cellular rejection (ACR) after reduction of immunosuppression. Conclusions: B19V infection should be suspected early as a cause of severe anemia of unknown etiology in adult liver transplant recipients. The clearance of B19V typically lags behind recovery of anemia, and inadequate clearance of virus after cessation of IVIG appears to be a potential risk of anemia recurrence. Moreover, more attention should be paid to the side effects of high-dose IVIG infusion and ACR because of reduction of immunosuppression.


Assuntos
Anemia , Transplante de Fígado , Infecções por Parvoviridae , Parvovirus B19 Humano , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Infecções por Parvoviridae/epidemiologia , Infecções por Parvoviridae/complicações , Infecções por Parvoviridae/terapia , Imunoglobulinas Intravenosas/uso terapêutico , Transplante de Fígado/efeitos adversos , Estudos Retrospectivos , Anemia/epidemiologia , Anemia/etiologia
9.
Membranes (Basel) ; 12(6)2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35736290

RESUMO

Approximately two-thirds of anthropogenic emissions causing global warming are from carbon dioxide. Carbon capture is essential, with membranes proving to be a low cost and energy-efficient solution to alternative technologies. In particular, mixed matrix membranes (MMMs) can have higher permeability and selectivity than pure polymer membranes. The fabrication conditions affect the formation of defects within the membranes. In this work, MMMs were created using a PEBAX MH-1657 polymer and a ZIF-8 filler. The effect of casting plate temperature, varying from -5 °C to 50 °C, and the effect of ultrasound treatment time (80-400 min) and method (filler solution only, filler and polymer combined solution only and filler solution followed by combined solution) were investigated, aiming to reduce defect formations hence improving the performance of the MMMs. SEM images and permeation tests using pure CO2 and N2 gas, replicating flue gas for carbon capture, were used to investigate and compare the membranes morphology and performance. The results indicated that the MMMs maintained their permeabilities and selectivities at all tested casting temperatures. However, the neat PEBAX membranes demonstrated increased phase separation of the polyamide and polyether oxide phases at higher temperatures, causing a reduction in permeability due to the higher crystallinity degree, confirmed by DSC experiment. The MMMs fabricated at low ultrasound times displayed a large amount of aggregation with large particle size causing channeling. At high ultrasound times, a well-dispersed filler with small filler diameters was observed, providing a high membrane performance. Overall, defect-free membranes were successfully fabricated, leading to improved performance, with the best membrane resulting from the longest ultrasound time reaching the Robeson bound upper limits.

11.
Int J Ophthalmol ; 13(11): 1720-1726, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33215001

RESUMO

AIM: To evaluate the safety, visual and anatomic outcomes of fourier-domain optical coherence tomography (FD-OCT)-guided excimer laser phototherapeutic keratectomy (PTK) combined with photorefractive keratectomy (PRK) surgery in treating anterior corneal scarring. METHODS: Clinical data of 23 eyes of 21 patients with anterior corneal scarring underwent FD-OCT-guided PTK and PRK from Dec. 2014 to Jul. 2016 were reviewed. Patients were assessed for preoperative and postoperative uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), contrast sensitivity (CS), FD-OCT, corneal topography and colour figures of anterior segments. RESULTS: The preoperative corneal pathologic conditions included viral keratitis (7 patients, 7 eyes), band keratopathy (2 patients, 4 eyes), corneal dystrophy (4 patients, 4 eyes), traumatic corneal disease (2 patients, 2 eyes) and corneal chemical injury (6 patients, 6 eyes). Mean follow-up time was 10.65 (range, 3-19)mo. UCVA (in logMAR) improved from a mean of 0.79 (95%CI, 0.28-1.29) preoperatively to a mean of 0.45 (95%CI, 0.29-0.62) postoperatively (P=0.021). BSCVA (in logMAR) improved from 0.57 (95%CI, 0.27-0.88) preoperatively to a mean of 0.28 (95%CI, 0.15-0.41) postoperatively (P=0.001). Corneal topographic indices postoperatively showed significant improvement in corneal cylinder (P=0.009), the surface regularity index (P=0.007) and surface asymmetry index (P=0.00). Postoperative spherical equivalent averaged -0.53 diopters (-1.49 to 0.42). No complications were associated with the treatment. CONCLUSION: FD-OCT-guided PTK combined with PRK is safe and effective for the treatment of anterior corneal scarring by eliminating or reducing corneal opacities.

12.
Ann Transplant ; 25: e921287, 2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-32366814

RESUMO

BACKGROUND Donor-specific tolerance is the ultimate goal in organ transplantation. Diverse approaches, including the use of mesenchymal stem cells (MSCs), have been investigated to induce graft tolerance. Non-stimulated MSCs showed limited regulatory functions through interaction with multiple immune-regulatory cells, such as regulatory T cells (Tregs). To augment their functions, MSCs have been preconditioned with toll-like receptor (TLR3/4) agonist in autoimmune disease models, but results were conflicting. MATERIAL AND METHODS We evaluated the immunomodulatory effects of mouse adipose-derived mesenchymal stem cells (ADSCs) preconditioned with various combinations of TLR3/4 agonist and antagonists, including polyinosinic-polycytidylic acid poly(I:C)-TLR3 agonist, lipopolysaccharide (LPS) -TLR4 agonist, and TAK242-TLR4 antagonist. In vitro and in vivo experiments including mixed lymphocyte reaction, cytokines measurement, Tregs analysis, and a fully mismatched MHC heterotopic heart transplantation in mice (BALB/c to C57BL/6) were conducted. RESULTS ADSCs preconditioned with poly(I:C) showed the highest efficiency in inhibiting lymphocyte proliferation, which was correlated with the upregulation of fibrinogen-like protein 2 (FGL2), an effector molecule of Tregs. The mean survival of cardiac allografts was extended from 8 to 12 days by intravenous injection of a single dose of ADSCs preconditioned with TLR3 agonist. The proportion of Tregs in the recipient's spleen was significantly increased by injecting the poly(I:C)-stimulated ADSCs. CONCLUSIONS These results show that short-term TLR3 agonist preconditioning enhances the immunomodulatory efficacy of ADSCs, which can induce the generation of Tregs and upregulate the expression of FGL2, thereby improving the outcome of patients receiving organ transplantation.


Assuntos
Rejeição de Enxerto/prevenção & controle , Transplante de Coração/efeitos adversos , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/efeitos dos fármacos , Receptor 3 Toll-Like/agonistas , Animais , Técnicas de Cultura de Células , Modelos Animais de Doenças , Fibrinogênio/metabolismo , Rejeição de Enxerto/etiologia , Masculino , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Receptor 4 Toll-Like/agonistas , Receptor 4 Toll-Like/antagonistas & inibidores
13.
Cancer Immunol Immunother ; 67(6): 907-915, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29511794

RESUMO

PURPOSE: It is now recognized that solid tumors encroach on the host's immune microenvironment to favor its own proliferation. Strategies to enhance the specificity of the endogenous T-cell population against tumors have been met with limited clinical success. We aimed to devise a two-tier protocol coupling in vivo whole antigen priming with ex vivo cellular expansion to clinically evaluate survival in patients following re-infusion of primed, autologous T cells, thereby determining treatment efficacy. EXPERIMENTAL DESIGN: Treatment commenced with the acquisition of whole tumor antigens from tumor cell lines corresponding with patients' primary malignancy. Lysate mixture was inoculated intradermally, while peripheral blood mononuclear cells (PBMCs) were periodically extracted via phlebotomy and expanded in culture ex vivo for re-infusion. Post-treatment tumor-specific T-cell response and cytotoxicity was confirmed via Elispot and real-time cell analyzing (RTCA) assay. Serum cytokine levels and cytotoxicity scores were evaluated for associations with survival status and duration. RESULTS: There was a significant increase in cytotoxicity exhibited by T cells measured using both Elispot and RTCA following treatment. Correlation analysis determined significant association between higher post-treatment cytotoxicity scores and survival status (R = 0.52, p = 0.0028) as well as longer survival duration in months (R = 0.59, p = 0.005). CONCLUSIONS: Our treatment protocol successfully demonstrated significant correlation between tumor-associated antigen-specific immune response and objective prolongation of survival. Whole-cell cancer antigen priming and adoptive T-cell therapy is, therefore, a highly feasible clinical model which can be easily replicated to positively influence outcome in end-stage malignancy.


Assuntos
Antígenos de Neoplasias/imunologia , Imunoterapia Adotiva/métodos , Neoplasias/imunologia , Linfócitos T Citotóxicos/imunologia , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/patologia
14.
Oncotarget ; 7(31): 49368-49383, 2016 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-27384999

RESUMO

Retinal regeneration and repair are severely impeded in higher mammalian animals. Although Müller cells can be activated and show some characteristics of progenitor cells when injured or under pathological conditions, they quickly form gliosis scars. Unfortunately, the basic mechanisms that impede retinal regeneration remain unknown. We studied retinas from Royal College of Surgeon (RCS) rats and found that let-7 family molecules, let-7e and let-7i, were significantly overexpressed in Müller cells of degenerative retinas. It demonstrated that down-regulation of the RNA binding protein Lin28B was one of the key factors leading to the overexpression of let-7e and let-7i. Lin28B ectopic expression in the Müller cells suppressed overexpression of let-7e and let-7i, stimulated and mobilized Müller glia de-differentiation, proliferation, promoted neuronal commitment, and inhibited glial fate acquisition of de-differentiated Müller cells. ERG recordings revealed that the amplitudes of a-wave and b-wave were improved significantly after Lin28B was delivered into the subretinal space of RCS rats. In summary, down-regulation of Lin28B as well as up-regulation of let-7e and let-7i may be the main factors that impede Müller cell de-differentiation and proliferation in the retina of RCS rats.


Assuntos
Desdiferenciação Celular , Células Ependimogliais/citologia , Neuroglia/metabolismo , Proteínas de Ligação a RNA/metabolismo , Retina/citologia , Animais , Ciclo Celular , Linhagem da Célula , Proliferação de Células , Regulação para Baixo , Eletrorretinografia , Feminino , Regulação Neoplásica da Expressão Gênica , Proteínas de Fluorescência Verde/metabolismo , Masculino , MicroRNAs/metabolismo , Ratos , Degeneração Retiniana/metabolismo , Células-Tronco/metabolismo
16.
Vision Res ; 110(Pt A): 107-17, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25817714

RESUMO

Our aim is to define related molecular events on how dormant Müller glia cells re-enter the cell cycle, proliferate and produce new retinal neurons from initial injury to glial scar formation. Sodium iodate (NaIO3) was used to induce acute retinal injury. Long-Evans rats were administered with NaIO3 or phosphate-buffered saline by intraperitoneal injection. The proliferation, dedifferentiation and neurogenesis of Müller cells were analyzed by double-labeled fluorescence immunohistochemistry with primary antibodies - against Müller cells and specific cell markers. Possible molecules that limit the regenerative potential of Müller cells were also determined by immunofluorescence staining, quantitative RT-PCR, protein array, ELISA and Western blot. In the first 3-7days after NaIO3 administration, Müller cells were activated and underwent a fate switch, including transient proliferation, dedifferentiation and neurogenesis. Nerve growth factor (NGF) signaling concomitantly increased with the downregulation of p27(Kip1) in Müller cells, which may promote Müller cells to re-enter the cell cycle. The transient increase of NGF signaling and the transient decrease of Notch signaling inhibited Hes1, which might enhance the neuronal differentiation of dedifferentiated Müller cells and suppress gliosis. Upregulated Notch and decreased NGF expressions limit dedifferentiation and neurogenesis, but induces retinal Müller cell gliosis at a later stage. We conclude that transient NGF upregulation and Notch1 downregulation may activate the transient proliferation, dedifferentiation and neurogenesis of Müller cells during NaIO3-induced acute retinal injury; which could be a therapeutic target for overcoming Müller cell gliosis. Such therapy could be potentially used for treating retinal-related diseases.


Assuntos
Desdiferenciação Celular/fisiologia , Diferenciação Celular/fisiologia , Células Ependimogliais/fisiologia , Fator de Crescimento Neural/fisiologia , Receptor Notch1/fisiologia , Retina/lesões , Neurônios Retinianos/fisiologia , Doença Aguda , Animais , Proliferação de Células/fisiologia , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Neurogênese/fisiologia , Ratos , Ratos Long-Evans , Reação em Cadeia da Polimerase em Tempo Real , Retina/citologia , Doenças Retinianas/fisiopatologia
17.
ACS Appl Mater Interfaces ; 7(3): 1780-6, 2015 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-25588129

RESUMO

Ammonium polyphosphates (APP) modified with piperazine (PA-APP) was used to improve the flame retardancy of poly(vinyl alcohol) (PVA)/montmorillonite (MMT) aerogels, which were prepared via an environmentally friendly freeze-drying method. The thermal stabilities of the samples were evaluated by thermogravimetric analysis (TG); the flammability behaviors of samples were investigated by limiting oxygen index (LOI), vertical burning test (UL-94) and cone calorimeter (CC) tests. TG test results showed that the 5% weight loss temperature (T5%) of PVA/MMT/PA-APP was 10 °C higher than that of PVA/MMT/APP. In combustion testing, all of PVA/MMT/PA-APP aerogels achieved V-0 ratings and have a higher LOI values than the unmodified PVA/MMT aerogel. Moreover, the aerogel with 1% PA-APP5, which means that the content of piperazine is 5% in PA-APP, decreased the cone calorimetry THR value to 5.71 MJ/m(2), and increased the char residue to 52%. The compressive modulus of PVA/MMT/PA-APP was increased by 93.4% compared with PVA/MMT/APP because of the increase in interfacial adhesion between matrix and PA-APP fillers. The densities of the PVA/MMT/PA-APP samples were slightly lower than those of the unmodified aerogels because of reduced shrinkage in the presence of PA-APP. All the tests results indicated that the incorporation of PA-APP not only improved the thermal stability and flame retardancy of aerogels but also maintained their mechanical properties.

18.
Exp Eye Res ; 132: 34-47, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25584870

RESUMO

Müller cells can completely repair retinal injury by acting as endogenous stem/progenitor cells in lower-order vertebrates. However, a safe and effective approach to activate progenitor potential of retinal Müller cells in higher-order vertebrates, which rarely re-enter the cell cycle, is a bottleneck problem. In the present study, Royal College of Surgeon's (RCS) rats were subjected to rat bone marrow mesenchymal stem cells (rBMSCs) subretinal space transplantation. Electroretinography (ERG) recordings showed that the b-wave amplitudes and ONL thicknesses statistically increased after transplantation. The number of Müller cells expressing proliferative, stem/progenitor and neuronal markers significantly increased after rBMSCs transplantation in vivo or after co-culturing with rBMSCs in vitro. The cultured rBMSCs could secrete nerve growth factor (NGF). In addition, we confirmed that NGF or NGF-neutralizing antibody could activate or depress Müller cells dedifferentiation, both in vivo and in vitro. Furthermore, Müller cells expressing high levels of the NGF receptor neurotrophic tyrosine kinase receptor type 1 (TrkA) were observed in the retinas of rats transplanted with rBMSCs. Moreover, the protein expression of downstream elements of NGF/TrkA signaling, such as p-PI3K, p-Akt and p-CREB, increased in Müller cells in the retinas of rBMSCs-treated rats in vivo or in Müller cells co-cultured with rBMSCs in vitro. Blocking TrkA with K-252a reduced the number of dedifferentiated Müller cells and the expression of NGF/TrkA signaling in vitro. Thus, rBMSCs might initiate endogenous regenerative mechanisms, which may constitute a new therapeutic strategy for retinal dystrophic diseases.


Assuntos
Células da Medula Óssea/citologia , Células Ependimogliais/fisiologia , Transplante de Células-Tronco Mesenquimais , Fator de Crescimento Neural/fisiologia , Receptor trkA/fisiologia , Retinose Pigmentar/cirurgia , Transdução de Sinais/fisiologia , Análise de Variância , Animais , Western Blotting , Diferenciação Celular/fisiologia , Modelos Animais de Doenças , Eletrorretinografia , Ensaio de Imunoadsorção Enzimática , Ratos , Reação em Cadeia da Polimerase em Tempo Real , Retinose Pigmentar/patologia , Retinose Pigmentar/fisiopatologia , Percepção Visual/fisiologia
19.
J Neurosci ; 34(36): 11929-47, 2014 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-25186741

RESUMO

The major cell classes of the brain differ in their developmental processes, metabolism, signaling, and function. To better understand the functions and interactions of the cell types that comprise these classes, we acutely purified representative populations of neurons, astrocytes, oligodendrocyte precursor cells, newly formed oligodendrocytes, myelinating oligodendrocytes, microglia, endothelial cells, and pericytes from mouse cerebral cortex. We generated a transcriptome database for these eight cell types by RNA sequencing and used a sensitive algorithm to detect alternative splicing events in each cell type. Bioinformatic analyses identified thousands of new cell type-enriched genes and splicing isoforms that will provide novel markers for cell identification, tools for genetic manipulation, and insights into the biology of the brain. For example, our data provide clues as to how neurons and astrocytes differ in their ability to dynamically regulate glycolytic flux and lactate generation attributable to unique splicing of PKM2, the gene encoding the glycolytic enzyme pyruvate kinase. This dataset will provide a powerful new resource for understanding the development and function of the brain. To ensure the widespread distribution of these datasets, we have created a user-friendly website (http://web.stanford.edu/group/barres_lab/brain_rnaseq.html) that provides a platform for analyzing and comparing transciption and alternative splicing profiles for various cell classes in the brain.


Assuntos
Processamento Alternativo , Córtex Cerebral/metabolismo , Bases de Dados de Ácidos Nucleicos , Endotélio Vascular/metabolismo , Neuroglia/metabolismo , Neurônios/metabolismo , Transcriptoma , Animais , Córtex Cerebral/irrigação sanguínea , Córtex Cerebral/citologia , Camundongos , Análise de Sequência de RNA
20.
Am J Respir Crit Care Med ; 189(4): 475-81, 2014 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-24450377

RESUMO

RATIONALE: Early diagnosis and treatment of tuberculous meningitis saves lives, but current laboratory diagnostic tests lack sensitivity. OBJECTIVES: We investigated whether the detection of intracellular bacteria by a modified Ziehl-Neelsen stain and early secretory antigen target (ESAT)-6 in cerebrospinal fluid leukocytes improves tuberculous meningitis diagnosis. METHODS: Cerebrospinal fluid specimens from patients with suspected tuberculous meningitis were stained by conventional Ziehl-Neelsen stain, a modified Ziehl-Neelsen stain involving cytospin slides with Triton processing, and an ESAT-6 immunocytochemical stain. Acid-fast bacteria and ESAT-6-expressing leukocytes were detected by microscopy. All tests were performed prospectively in a central laboratory by experienced technicians masked to the patients' final diagnosis. MEASUREMENTS AND MAIN RESULTS: Two hundred and eighty patients with suspected tuberculous meningitis were enrolled. Thirty-seven had Mycobacterium tuberculosis cultured from cerebrospinal fluid; 40 had a microbiologically confirmed alternative diagnosis; the rest had probable or possible tuberculous meningitis according to published criteria. Against a clinical diagnostic gold standard the sensitivity of conventional Ziehl-Neelsen stain was 3.3% (95% confidence interval, 1.6-6.7%), compared with 82.9% (95% confidence interval, 77.4-87.3%) for modified Ziehl-Neelsen stain and 75.1% (95% confidence interval, 68.8-80.6%) for ESAT-6 immunostain. Intracellular bacteria were seen in 87.8% of the slides positive by the modified Ziehl-Neelsen stain. The specificity of modified Ziehl-Neelsen and ESAT-6 stain was 85.0% (95% confidence interval, 69.4-93.8%) and 90.0% (95% confidence interval, 75.4-96.7%), respectively. CONCLUSIONS: Enhanced bacterial detection by simple modification of the Ziehl-Neelsen stain and an ESAT-6 intracellular stain improve the laboratory diagnosis of tuberculous meningitis.


Assuntos
Antígenos de Bactérias/líquido cefalorraquidiano , Proteínas de Bactérias/líquido cefalorraquidiano , Leucócitos/microbiologia , Mycobacterium tuberculosis/isolamento & purificação , Tuberculose Meníngea/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/líquido cefalorraquidiano , Criança , Pré-Escolar , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis/imunologia , Estudos Prospectivos , Sensibilidade e Especificidade , Coloração e Rotulagem , Tuberculose Meníngea/líquido cefalorraquidiano , Adulto Jovem
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