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The aim of this study was to identify angiogenic microRNAs (miRNAs) that could be used in the treatment of hindlimb ischemic tissues. miRNAs contained in extracellular vesicles (EVs) deriving from the plasma were analyzed in C57BL/6 mice, which have ischemia tolerance, and in BALB/c mice without ischemia tolerance as part of a hindlimb ischemia model; as a result 43 angiogenic miRNA candidates were identified. An aortic ring assay was employed by using femoral arteries isolated from BALC/c mice and EVs containing miRNA; as a result, the angiogenic miRNA candidates were limited to 14. The blood flow recovery was assessed after injecting EVs containing miRNA into BALB/c mice with hindlimb ischemia, and miR-709 was identified as a promising angiogenic miRNA. miR-709-encapsulating EVs were found to increase the expression levels of the fibroblast growth factor 2 (FGF2) mRNA in the thigh tissues of hindlimb ischemia model BALB/c mice. miR-709 was also found to bind to the 3'UTR of glycogen synthase kinase 3 beta (GSK3B) in three places. GSK3B-knockdown human artery-derived endothelial cells were found to express high levels of FGF2, and were characterized by increased cell proliferation. These findings indicate that miR-709 induces an upregulation of FGF2 through the downregulation of GSK3B.
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Factor 2 de Crecimiento de Fibroblastos , Glucógeno Sintasa Quinasa 3 beta , Miembro Posterior , Isquemia , Ratones Endogámicos BALB C , MicroARNs , Neovascularización Fisiológica , Animales , Humanos , Masculino , Ratones , Regiones no Traducidas 3' , Proliferación Celular , Modelos Animales de Enfermedad , Regulación hacia Abajo , Células Endoteliales/metabolismo , Vesículas Extracelulares/metabolismo , Factor 2 de Crecimiento de Fibroblastos/metabolismo , Factor 2 de Crecimiento de Fibroblastos/genética , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Glucógeno Sintasa Quinasa 3 beta/genética , Miembro Posterior/irrigación sanguínea , Isquemia/metabolismo , Isquemia/genética , Ratones Endogámicos C57BL , MicroARNs/genética , MicroARNs/metabolismo , Neovascularización Fisiológica/genética , Regulación hacia ArribaRESUMEN
In our previous study, we found that dry-preserved multilayered fibroblast cell sheets promoted angiogenesis and wound healing in a mouse ulcer model by releasing high levels of intracellular fibroblast growth factor 2 (FGF2), hepatocyte growth factor (HGF), and vascular endothelial growth factor (VEGF), from dried cells. In the present study, to identify which cell types are suitable for human dry-preserved cell sheets (dry sheets), we compared the intracellular FGF2 levels in seven types of cells reported as cell sheets for clinical use or preclinical studies. FGF2 levels were high in mesenchymal cells, including human oral fibroblasts (HOFs) and human dermal fibroblasts (HDFs), human dental pulp stem cells (DPSCs), and human mesenchymal stem cells (MSCs); in contrast, FGF2 levels in human umbilical vascular endothelial cells (HUVECs), human skeletal muscle myoblasts (SkMMs), and human epidermal keratinocytes (HEKs) were remarkably low, approximately 25% those in fibroblasts. In addition, we prepared dry sheets from HOFs, DPSCs, and MSCs, and analyzed the growth factors released from each dry sheet upon rehydration. High levels of FGF2, HGF, and VEGF were detected in the eluate prepared by immersing each dry sheet. In particular, FGF2 and HGF were the most abundant in HOFs. An in vitro cell proliferation assay showed that these eluates significantly enhanced HUVEC proliferation compared to control cells. Furthermore, cells incubated with HOF eluate showed significantly higher cell proliferation than cells incubated with DPSC and MSC eluates. However, this proliferative response was significantly blocked by FGF2-neutralizing antibodies. These results demonstrate that growth factors released from human dry sheets have physiological activity and that this activity is mainly mediated by the effect of FGF2. Fibroblasts are ideal for the clinical application of dry-preserved cell sheets in humans owing to their high intracellular FGF2 content, fast cell proliferation, ease of handling, availability, and low culture costs, making them the most suitable cell source for regenerative medicine, with FGF2 release as the mechanism of action.
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OBJECTIVE: Anastomotic leakage is a common and severe complication of esophageal reconstruction. Accordingly, there is a clinical need for novel methods to prevent it. We developed multilayered, growth factor-secreting fibroblast sheets that promote wound healing and angiogenesis. The present study aimed to assess the utility of allogenic multilayered fibroblast sheets in preventing esophageal anastomotic leakage in a rat model of esophageal reconstruction. METHODS: Allogenic multilayered fibroblast sheets prepared from oral mucosal tissues were implanted at esophageal anastomotic sites. RESULTS: The allogenic multilayered fibroblast sheet group had significantly higher burst pressure and collagen deposition compared to a control group five days postoperatively. The expression levels of collagen type I and III mRNAs around esophageal suture sites were higher in the allogenic multilayered fibroblast sheet group compared to the control group on postoperative days 0, 3, and 5. There was a trend toward lower anastomotic leakage and lower abscess scores in the allogenic multilayered fibroblast sheet group compared to the control group; however, these differences did not reach statistical significance. Allogenic multilayered fibroblast sheets completely disappeared at ten days after implantation. Further, no inflammation was observed at suture sites with implanted allogenic multilayered fibroblast sheets at five days after surgery. CONCLUSION: Allogenic multilayered fibroblast sheets may represent a promising method of preventing esophageal anastomotic leakage.
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The purpose of this study was to investigate the therapeutic effect of cryopreserved allogenic fibroblast cell sheets in a mouse model of skin ulcers. It is necessary to reduce the cost of regenerative medicine for it to be widely used. We consider that cell sheets could be applied to various diseases if cryopreservation of allogenic cell sheets was possible. In this study, fibroblasts were frozen using a three-dimensional freezer. Freeze-thawed fibroblasts had ~80% cell viability, secreted ≥ 50% vascular endothelial growth factor, hepatocyte growth factor, and stromal derived factor-1α compared with non-frozen fibroblast sheets, and secreted approximately the same amount of transforming growth factor-ß1. There was no difference in wound-healing rates in the skin ulcer model between non-frozen and freeze-thawed fibroblast sheets regardless of autologous and allogenic cells. The degree of angiogenesis was comparable between autologous and allogenic cells. The number of CD3-positive cells in healed tissues was larger for allogenic fibroblast sheets compared with autologous fibroblast sheets. However, histopathological images showed that the fibrosis, microvascular density, and healing phase of the wound in allogenic freeze-thawed fibroblast sheets were more similar to autologous freeze-thawed fibroblast sheets than to allogenic non-frozen fibroblast sheets. These results suggest that allogenic freeze-thawed fibroblast sheets may be a promising therapeutic option for refractory skin ulcers.
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This study investigated the therapeutic effects of dry-preserved multi-layered fibroblast cell sheets (dry sheets) on cutaneous ulcers. Dry sheets were prepared by air-drying multi-layered fibroblast cell sheets (living sheets) to cease their life activities. Before in vivo application, we tested the release of growth factors into the medium to examine the mechanisms of dry sheets in wound healing. Vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) were released from both dry and living sheets, while high levels of fibroblast growth factor-2 (FGF-2) and high mobility group box 1 (HMGB1) protein were only from dry sheets. An in vitro fibroblast proliferation assay revealed that the dry sheet eluate significantly enhanced cell proliferation and VEGF and HGF production compared with living sheet eluate. FGF-2-neutralizing antibodies significantly blocked this proliferative response. In wounds created on diabetic mice, the dry sheet-treatment groups using autologous or allogeneic cells showed significantly accelerated wound closure compared with that in the no-treatment group. The storage stability of the dry sheet was better at refrigeration temperature than at room temperature and remained stable for at least 4 weeks. Our data indicated that allogeneic dry sheets represent a promising new tool for regenerative medicine that promotes wound healing.
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Diabetes Mellitus Experimental , Medicina Regenerativa , Animales , Diabetes Mellitus Experimental/metabolismo , Factor 2 de Crecimiento de Fibroblastos/metabolismo , Fibroblastos/metabolismo , Ratones , Factor A de Crecimiento Endotelial Vascular/metabolismo , Cicatrización de HeridasRESUMEN
INTRODUCTION: Postoperative pancreatic fistula (POPF) is a serious complication after gastrointestinal or pancreatic surgery. Despite intensive investigations, the occurrence has not significantly decreased in the past decades. The aims of this study were to clarify the pathophysiology of POPF and establish the preventive measures using multilayered fibroblast sheets. METHODS: We developed a pancreatic fistula (PF) model of rat with transection of the splenic duct and surrounding pancreatic parenchyma. Multilayered fibroblast sheets prepared from tails were autologously transplanted to this model. The preventive effect was biochemically and histologically evaluated by measuring the ascitic levels of pancreatic enzymes and conducting immunohistochemistry and real-time polymerase chain reaction analyses of pancreatic tissue. Findings were compared to those obtained with acellular materials simply sealing the wound. RESULTS: In the PF model, the ascitic levels of pancreatic enzymes were transiently up-regulated. Inflammation and necrosis were histologically observed in a wide range. Islets were damaged even in remote areas. Transplantation of multilayered fibroblast sheets dramatically reduced the ascitic leakage of enzymes, suppressed inflammation, and broadly preserved the islets. Compared with acellular materials, these sheets offered superior prevention of cellular activity through the spaciotemporal regulation of fibrosis and angiogenesis. Notably, the leakage hole appeared to have been plugged with the fibrotic matrix, which might have been the most crucial mechanism minimizing pancreatic damage. CONCLUSIONS: The autologous transplantation of multilayered fibroblast sheets significantly prevented PF and protected the pancreas, underscoring the potential utility of this approach for POPF prevention.
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OBJECTIVES: Cell therapy provides a suitable environment for regeneration through paracrine effects such as secretion of growth factors. Cardiosphere-derived cells (CDCs) have a high capacity for growth factor secretion and are an attractive target for clinical applications. In particular, a cell sheet technique was reported to have clinical advantages by covering a specific region. Here, we examined the effect of the hypoxic-conditioned (HC) autologous CDC sheet therapy on a rabbit chronic myocardial infarction model. METHODS: CDC sheet function was assessed by the enzyme-linked immunosorbent assay and quantified by polymerase chain reaction in vitro (days 1-3 of conditioning). The rabbit chronic myocardial infarction model was established by left coronary ligation. Autologous CDCs were isolated from the left atrial specimen; CDC sheets with or without 2-day HC were transplanted onto the infarcted hearts at 4 weeks. The cardiac function was assessed by an echocardiography at 0, 4 and 8 weeks. A histological analysis of the host hearts was performed by tomato lectin staining at 8 weeks. RESULTS: The optimal HC duration was 48 h. HC significantly increased the mRNA expression levels of VEGF and ANG2 on day 2 compared to the normoxic-conditioned (NC) group. The HC group showed significant improvement in the left ventricular ejection fraction (64.4% vs 58.8% and 53.4% in the NC and control) and a greater lectin-positive area in the ischaemic region (HC:NC:control = 13:8:2). CONCLUSIONS: HC enhances the paracrine effect of a CDC sheet on angiogenesis to improve cardiac function in the chronic myocardial infarction model, which is essential for cardiomyocyte proliferation during cardiac regeneration.
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Infarto del Miocardio , Miocitos Cardíacos , Trasplante de Células Madre , Función Ventricular Izquierda/fisiología , Animales , Hipoxia de la Célula/fisiología , Modelos Animales de Enfermedad , Masculino , Infarto del Miocardio/fisiopatología , Infarto del Miocardio/terapia , Miocitos Cardíacos/citología , Miocitos Cardíacos/trasplante , ConejosRESUMEN
BACKGROUND: Epstein-Barr virus (EBV) is an oncogenic human herpesvirus involved in the development of around 10% of gastric cancers. The overexpression of PD-L1 is one of the features of EBV-associated gastric cancer (EBVaGC); however, the function of PD-L1 has not been studied in EBVaGC. METHODS: We used three EBVaGC cell lines, SNU719 cells, NCC24 cells, and YCCEL1 cells, to evaluate the PD-L1 expression and function in EBVaGC. Jurkat T-lymphocytes expressing PD-1 were co-cultured with NCC24 and YCCEL1 cells and the cell cycles were analyzed. To study the regulatory mechanism for PD-L1 expression, the 3'UTR of PD-L1 was sequenced, and the effect of inhibitors of the IFN-γ signaling pathway was evaluated. RESULTS: All of the EBVaGC cell lines expressed PD-L1, and its expression was further enhanced by stimulation with IFN-γ. In Jurkat T-cells co-cultured with IFN-γ-stimulated NCC24 and YCCEL1 cells, the number of cells in the G0/G1 phase was significantly increased. This G0/G1 arrest was partially released by administration of anti-PD-L1 antibody. We found SNPs in PD-L1 3'UTR nucleotide sequences that were located at seed regions for microRNAs. Treatment of EBVaGC cell lines with JAK2-inhibitor, PI3K-inhibitor, and mTOR inhibitor reduced the level of PD-L1 expression to the same level as cells without IFN-γ stimulation. CONCLUSIONS: EBVaGC cells expressing high levels of PD-L1 suppress T-cell proliferation, and the IFN-γ signaling pathway is involved in the expression of PD-L1.
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Antígeno B7-H1/metabolismo , Infecciones por Virus de Epstein-Barr/complicaciones , Regulación Neoplásica de la Expresión Génica , Herpesvirus Humano 4/inmunología , Receptor de Muerte Celular Programada 1/metabolismo , Neoplasias Gástricas/inmunología , Linfocitos T/inmunología , Apoptosis , Antígeno B7-H1/genética , Ciclo Celular , Proliferación Celular , Inhibidores Enzimáticos/farmacología , Infecciones por Virus de Epstein-Barr/virología , Humanos , Polimorfismo de Nucleótido Simple , Receptor de Muerte Celular Programada 1/genética , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patología , Neoplasias Gástricas/virología , Linfocitos T/efectos de los fármacos , Linfocitos T/metabolismo , Células Tumorales CultivadasRESUMEN
BACKGROUND/AIMS: We have developed a method to transplant sheets of autologous fibroblasts and peripheral blood mononuclear cells, which are highly angiogenic and regenerative, as treatment against refractory cutaneous ulcers in mice and rabbits. The cell sheets are also sealed with fibrin to further enhance effectiveness. METHODS: Secretion of growth factors from cells incubated with or without fibrin in vitro was assessed by enzyme-linked immunosorbent assays, while angiogenesis and fibroblast migration were assessed by tube formation and scratch assays. Healing of cutaneous ulcers following transplantation of cells was evaluated in mice with diabetes mellitus. RESULTS: Secretion of vascular endothelial growth factor, hepatocyte growth factor, and transforming growth factor was much higher from cell sheets supplemented with fibrin than from cell sheets only. Accordingly, supernatants from the former enhanced angiogenesis and fibroblast migration in vitro. Cutaneous ulcers treated with fibrin-glued cell sheets also healed more quickly than untreated ulcers or ulcers treated with cell sheets only. CONCLUSION: Fibrin-sealed cells accelerate wound healing and microvascularization by supplying growth factors, and thus are promising as treatment against refractory cutaneous ulcers.
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We used real-time PCR to detect Bartonella henselae DNA in 7.9% (5/63) of blood specimens from seronegative patients in Japan suspected of having cat-scratch disease. The combined use of serologic tests and real-time PCR to analyze blood specimens is recommended for the prompt, noninvasive laboratory diagnosis of cat-scratch disease.
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Anticuerpos Antibacterianos/sangre , Bartonella henselae/aislamiento & purificación , Enfermedad por Rasguño de Gato/diagnóstico , Enfermedad por Rasguño de Gato/microbiología , ADN Bacteriano/aislamiento & purificación , Adolescente , Adulto , Bartonella henselae/genética , Niño , Preescolar , Femenino , Humanos , Japón/epidemiología , Masculino , Persona de Mediana Edad , Pruebas SerológicasRESUMEN
We evaluated the utility of Western blot (WB) bands of Bartonella henselae in detecting anti-B. henselae immunoglobulin M (IgM) for serodiagnosis of cat scratch disease (CSD). IgM band patterns were examined using sera from 92 patients clinically suspected of having CSD and from 130 healthy individuals. Positive WB bands were observed in 49 (53.5%) of the 92 patient sera. Three bands at 8 to 10, 31 to 35, and 70 kDa were regarded as relevant for B. henselae because all of the positive sera yielded at least one of the three bands, and none of the healthy control sera showed reactivity to any of them. In contrast, the positive rate of the patient sera by conventional indirect fluorescence antibody assay (IFA) for B. henselae IgM was 28.3% (26/92) among the patients. These finding suggest that the IgM-WB assay, although cumbersome to perform, can be used for confirmatory diagnosis of CSD with no false positivity in the control sera. Purification of proteins in the specific bands may contribute to the development of an IgM enzyme-linked immunosorbent assay (IgM-ELISA) with improved specificity and sensitivity.
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Anticuerpos Antibacterianos/sangre , Bartonella henselae/inmunología , Enfermedad por Rasguño de Gato/diagnóstico , Inmunoglobulina M/sangre , Pruebas Serológicas/métodos , Especificidad de Anticuerpos , Bartonella henselae/aislamiento & purificación , Western Blotting , Enfermedad por Rasguño de Gato/inmunología , Humanos , Sensibilidad y EspecificidadRESUMEN
The Epstein-Barr virus (EBV) is detected in about 10% of gastric carcinoma cases throughout the world. In EBV-associated gastric carcinoma (EBVaGC), all tumor cells harbor the clonal EBV genome. The expression of latent EBV genes is strictly regulated through the methylation of EBV DNA. The methylation of viral DNA regulates the type of EBV latency, and methylation of the tumor suppressor genes is a key abnormality in EBVaGC. The methylation frequencies of several tumor suppressor genes and cell adhesion molecules are significantly higher in EBVaGC than in control cases. EBV-derived microRNAs repress translation from viral and host mRNAs. EBV regulates the expression of non-coding RNA in gastric carcinoma. With regard to the clinical application of demethylating agents against EBVaGC, we investigated the effects of decitabine against the EBVaGC cell lines. Decitabine inhibited the cell growth of EBVaGC cells. The promoter regions of p73 and Runt-related transcription factor 3(RUNX3) were demethylated, and their expression was upregulated by the treatment. We review the role of epigenetic regulation in the development and maintenance of EBVaGC and discuss the therapeutic application of DNA demethylating agents for EBVaGC.
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Metilación de ADN , Infecciones por Virus de Epstein-Barr/genética , Herpesvirus Humano 4/patogenicidad , MicroARNs/genética , Neoplasias Gástricas/virología , Antimetabolitos Antineoplásicos/farmacología , Antimetabolitos Antineoplásicos/uso terapéutico , Azacitidina/análogos & derivados , Azacitidina/farmacología , Azacitidina/uso terapéutico , Subunidad alfa 3 del Factor de Unión al Sitio Principal/genética , Islas de CpG/efectos de los fármacos , Metilación de ADN/efectos de los fármacos , ADN Viral/genética , Decitabina , Epigénesis Genética/efectos de los fármacos , Infecciones por Virus de Epstein-Barr/tratamiento farmacológico , Infecciones por Virus de Epstein-Barr/virología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Regulación Viral de la Expresión Génica/efectos de los fármacos , Herpesvirus Humano 4/efectos de los fármacos , Herpesvirus Humano 4/genética , Humanos , ARN Viral/genética , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/genética , Proteína Tumoral p73/genéticaRESUMEN
Bartonella henselae strains genetically differ among nations. The utility of Japanese-specific YH-01 strain was investigated in developing indirect fluorescence antibody assay (IFA) for IgM in comparison with conventional IFA employing Houston-1 strain by testing 100 Japanese patients suspected of cat scratch disease. The country-specific IFA greatly improved the accuracy of diagnosis.
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Anticuerpos Antibacterianos/sangre , Antígenos Bacterianos/inmunología , Bartonella henselae/inmunología , Enfermedad por Rasguño de Gato/diagnóstico , Pruebas Diagnósticas de Rutina/métodos , Técnica del Anticuerpo Fluorescente Indirecta/métodos , Inmunoglobulina M/sangre , Adolescente , Adulto , Animales , Gatos , Preescolar , Femenino , Humanos , Japón , Masculino , Adulto JovenRESUMEN
The conventional anti-Bartonella henselaeIgM enzyme-linked immunosorbent assay (IgM-ELISA) methods for diagnosing cat scratch disease (CSD) remain poor in both sensitivity and specificity. We sought to develop an IgM-ELISA with improved accuracy in the serodiagnosis of CSD by exploring the antigens that are most suitable for an ELISA. We prepared 5 different protein antigens: antigen I (sonicatedB. henselaewhole-cell antigen), antigen II (N-lauroyl-sarcosine-insoluble antigen), antigen III (processed sarcosine-soluble antigen), and antigen IV and antigen V (sarcosine-insoluble and sarcosine-soluble antigens refined by DEAE-Sepharose Fast Flow ion-exchange chromatography). The IgM antibodies in the sera of 47 patients with clinically suspected CSD (24 definite, 23 suspected) and of 85 healthy individuals were examined by ELISAs using the 5 antigens, and the results were compared with those of an IgM indirect fluorescent antibody assay (IgM-IFA). In a reference panel, which consisted of 5 positive and 5 negative sera, antigen I and antigen III failed to distinguish between the two statuses, whereas the other three antigens succeeded in distinguishing between them. When the cutoff value was set at the 98th percentile of the ELISA index for healthy individuals, the sensitivity of IgM-IFA for the 24 cases of definite CSD was 54%, whereas the sensitivities of the IgM-ELISAs with antigen II, IV, and V were 75%, 83%, and 75%, respectively. The sensitivities of these three IgM-ELISAs for all 47 of the clinically suspected cases were 49%, 64%, and 51%, respectively. In contrast, the sensitivity of IgM-IFA was 28%. These results indicate that the refined sarcosine-insoluble proteins (antigen IV), which possessed the highest specificity among the 5 antigens, are the most appropriate for developing an IgM-ELISA for the highly specific serodiagnosis of CSD.
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Anticuerpos Antibacterianos/sangre , Bartonella henselae/inmunología , Enfermedad por Rasguño de Gato/diagnóstico , Ensayo de Inmunoadsorción Enzimática/métodos , Inmunoglobulina M/sangre , Pruebas Serológicas/métodos , Antígenos Bacterianos/inmunología , Antígenos Bacterianos/aislamiento & purificación , Humanos , Sensibilidad y EspecificidadRESUMEN
We present the case of a 6-year-old girl with cat-scratch disease (CSD), who developed severe pleuritis without lymphadenitis. Bartonella henselae DNA was detected on real-time polymerase chain reaction (PCR) analysis of whole blood. This is the first report of CSD diagnosed on real-time PCR using whole blood.
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Bartonella henselae/aislamiento & purificación , Enfermedad por Rasguño de Gato/complicaciones , Pleuresia/etiología , Bartonella henselae/genética , Enfermedad por Rasguño de Gato/diagnóstico , Enfermedad por Rasguño de Gato/microbiología , Niño , ADN Bacteriano/análisis , Diagnóstico Diferencial , Femenino , Humanos , Pleuresia/diagnóstico , Pleuresia/microbiología , Radiografía Torácica , Reacción en Cadena en Tiempo Real de la Polimerasa , Índice de Severidad de la Enfermedad , Tomografía Computarizada por Rayos XRESUMEN
We report on a path-independent insertion-loss (PILOSS) 8 × 8 matrix switch based on Si-wire waveguides, which has a record-small footprint of 3.5 × 2.4 mm2. The PILOSS switch consists of 64 thermooptic Mach-Zehnder (MZ) switches and 49 low-crosstalk intersections. Each of the MZ switches and intersections employs directional couplers, which enable the composition of a low loss PILOSS switch. We demonstrate successful switching of digital-coherent 43-Gbps QPSK signal.
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BACKGROUND: Therapeutic hypothermia protects neurons after severe brain damage. This effect has been mainly achieved at the core temperatures of 32-34 °C; however, the optimum temperature of therapeutic hypothermia is not fully defined. Here we studied whether hypothermic culture at 35 °C had the same effects on the decrease of time-dependent expression of tumor necrosis factor (TNF)-α, interleukin (IL)-10, and nitric oxide (NO) by stimuli-activated microglia as that at 33 °C, as determined in our previous reports, and whether these factors directly induced neuronal cell death. METHODS: We determined the levels of cytokines and NO produced by microglia cultured with adenosine triphosphate (ATP), a toll-like receptor (TLR)2 agonist (N-palmitoyl-S-(2,3-bis(palmitoyloxy)-(2R,S)-propyl)-(R)-cysteinyl-seryl-(lysyl)3-lysine, Pam(3)CSK(4)), or a TLR4 agonist (lipopolysaccharide) under mild hypothermic (33 °C), minimal hypothermic (35 °C), and normothermic (37 °C) conditions. We also determined the viability of rat neuronal pheochromocytoma PC12 cells treated with recombinant TNF-α or IL-10 or (±)-(E)-4-ethyl-2-[(E)-hydroxyimino]-5-nitro-3-hexenamide (NOR3, an NO donor). RESULTS: Production of TNF-α, as well as that of IL-10 and NO were decreased by minimal hypothermia at 1.5-6, and 24-48 h, respectively, compared with normothermia, although some effects were diminished as compared with those by mild hypothermia. Exposure to TNF-α, IL-10, and NOR3 caused the death of PC12 cells in a concentration-dependent manner after 24 h. CONCLUSION: Hypothermic culture at 35 °C decreased the production of early-phase TNF-α and late-phase IL-10 and NO from ATP- and TLR-activated microglia as observed at 33 °C, albeit with diminished effects. Moreover, these factors caused the death of neuronal cells in a concentration-dependent manner. These results suggest that the attenuation of microglial production of TNF-α, IL-10, and NO by therapeutic hypothermia leads to the inhibition of neuronal cell death. Minimal hypothermia at 35 °C may be sufficient to elicit neuroprotective effect.
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Hipotermia Inducida , Interleucina-10/biosíntesis , Microglía/metabolismo , Neuronas/fisiología , Óxido Nítrico/biosíntesis , Factor de Necrosis Tumoral alfa/biosíntesis , Animales , Muerte Celular/inmunología , Microglía/inmunología , Células PC12 , Ratas , TemperaturaRESUMEN
Conventional IgG-ELISA methods for diagnosing cat scratch disease (CSD) caused by Bartonella hensela are still poor in sensitivity and specificity, which generally employ bacterial whole-cell proteins or N-lauroyl-sarcosine-insoluble proteins as the antigen. By Western blot analysis, we found that sarcosine-soluble fraction of proteins (SSP) showed highly specific reaction to immunofluorescence assay (IFA)-positive sera obtained from CSD patients compared with the above antigens. Clinical utility of the new ELISA employing SSP was evaluated using sera from 118 patients with clinically suspected CSD (sera positive by IFA: titers ≥ 1:256, n = 46; negative: titers <128, n = 72) and 88 sera from healthy individuals. Sensitivity and specificity of distinguishing IFA-positive patients from healthy individuals were 95.7% and 97.7%, respectively. Fifteen discordant results were observed (13 ELISA(+)/IFA(-); 2 ELISA(-)/IFA(+)). However, all 15 sera reacted with SSP by Western blot analysis, indicating superiority of the new ELISA over IFA. The ELISA employing SSP greatly improved the accuracy of diagnosing CSD.
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Anticuerpos Antibacterianos/sangre , Antígenos Bacterianos , Proteínas Bacterianas , Bartonella henselae/inmunología , Enfermedad por Rasguño de Gato/diagnóstico , Inmunoglobulina G/sangre , Adulto , Antígenos Bacterianos/aislamiento & purificación , Proteínas Bacterianas/aislamiento & purificación , Niño , Preescolar , Detergentes/metabolismo , Ensayo de Inmunoadsorción Enzimática/métodos , Humanos , Sarcosina/análogos & derivados , Sarcosina/metabolismo , Sensibilidad y Especificidad , Pruebas Serológicas/métodosRESUMEN
INTRODUCTION: In systemic lupus erythematosus (SLE) patients, the prevalence of arteriosclerosis obliterans (ASO) is high despite a lack of common risk factors for ASO. The main objective of this study was to investigate a possible direct role of anti-phospholipid antibodies (aPLs), which are frequently detected in SLE patients, in the pathogenesis of ASO. MATERIALS AND METHODS: We examined tissue factor (TF) expression on the monocyte surface by flow cytometric analysis in 89 SLE patients with or without ASO and/or aPLs and studied the in vitro effect of purified IgG fractions from plasma of SLE patients or normal healthy volunteers (aPLs(+) IgG, n=8; aPLs(-) IgG, n=6; Normal IgG, n=6) on the expression of TF and production of TNF-α and IL-1ß in healthy peripheral blood mononuclear cells (PBMCs) or isolated monocytes. RESULTS: We confirmed that high expression of monocyte TF was strongly associated with the prevalence of ASO and the presence of aPLs. Treatments of PBMCs with aPLs(-) IgG or normal IgG did not significantly increase expression of TF, TNF-α, and IL-1ß messenger RNA (mRNA) and the production of TNF-α and IL-1ß. However, stimulation of PBMCs with aPLs(+) IgG caused significant increase in expression of TF, TNF-α, and IL-1ß mRNA. Moreover, aPLs(+) IgG stimulated PBMCs and significantly enhanced the production of TNF-α and IL-1ß. CONCLUSION: These results suggest that IgG-aPLs cause persistently high TF expression and inflammatory cytokine production by interacting with peripheral blood monocytes and lymphocytes, which may be an important mechanism in the pathogenesis of ASO peculiar to SLE patients.