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A nickel-catalyzed three-component tandem radical cyclization reaction of aryl bromides with 1,3-enynes and aryl boric acids to construct γ-lactam-substituted allene derivatives has been described. This protocol provides lactam alkyl radicals through the free radical cyclization process, which can be effectively used to participate in the subsequent multicomponent coupling reaction so that 1,3-enynes could directly convert into corresponding poly-substituted allene compounds. In addition, this efficient method enjoys a broad substrate scope and provides a series of 1,5-difunctionalized allenes in a one-pot reaction.
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Burkholderia pseudomallei is the etiological agent of melioidosis, which is an emerging infectious disease endemic to many tropical regions. Autophagy is an intrinsic cellular process that degrades cytoplasmic components and plays an important role in protecting the host against pathogens. Like many intracellular pathogens, B. pseudomallei can evade the autophagy-dependent cellular clearance. However, the underlying mechanism remains unclear. In this study, we applied a combination of multiple assays to monitor autophagy processes and found that B. pseudomallei induced an incomplete autophagic flux and eliminate autophagy clearance in macrophages by blocking autophagosome-lysosome fusion. Based on a high-throughput microarray screening, we found that LIPA (lysosomal acid LIPAse A) was downregulated during B. pseudomallei infection. MiR-146a was then identified to be specifically upregulated upon infection with B. pseudomallei and further regulated LIPA expression by interacting with 3'UTR of LIPA. Furthermore, overexpression of miR-146a contributed to the defect of autophagic flux caused by B. pseudomallei and was beneficial for the survival of B. pseudomallei in macrophages. Therefore, our findings suggest that miR-146a inhibits autophagy via posttranscriptional suppression of LIPA expression to maintain B. pseudomallei survival in macrophages.
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Burkholderia pseudomallei , Macrófagos/microbiologia , Melioidose , MicroRNAs , Esterol Esterase , Animais , Autofagia , Burkholderia pseudomallei/genética , Células HEK293 , Humanos , Camundongos , MicroRNAs/genética , Células RAW 264.7RESUMO
A prolonged second stage of vaginal delivery increases the risk of shoulder dystocia, unnecessary episiotomies and cesarean sections. However, no standardized method has been proposed to tackle this issue. The effects of pelvic floor myofascial manipulation intervention during the second stage of labor in primiparas and its prognostic value in neonatal postpartum outcomes remain unknown. In the present study, a total of 60 primiparas who were expecting a vaginal delivery in the Second Affiliated Hospital of Hainan Medical College (Haikou, China) between October 2021 and January 2022 were selected. These women were randomly assigned to a control group (standard intrapartum care) or an experimental group (pelvic floor myofascial manipulation for 15-20 min during the second stage of labor along with standard intrapartum care) using a random number table, with 28 patients in each group. There was no significant difference in age, gestational time or body mass index between the two groups before delivery, indicating that the baseline data were comparable. The second stage of labor duration, forced breath-holding time and postpartum hemorrhage volume in the experimental group were significantly lower than those in the control group. The pain visual analog scale scores, fatigue scores and neonatal Apgar scores in the experimental group were also significantly lower than those in the control group. The rate of episiotomy in the experimental group was lower than that in the control group, but the difference was not statistically significant. In conclusion, pelvic floor myofascial manipulation intervention during the second stage of labor for primiparas with vaginal delivery can reduce the duration of the second stage of labor, the amount of bleeding during labor and the pain during labor. Meanwhile, it has the potential to improve neonatal outcomes.
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BACKGROUND: The changes in Notch signaling are closely related to the occurrence and development of many cancers. We have investigated Notch signaling receptor and its ligand expressions in TSCC cell lines, tissues and its significance. We clarified Notch signaling pathway in TSCC and its mechanism. We regulated Notch signaling pathway of tumor cells, thereby inhibiting tumor cell proliferation and differentiation. METHODS: We detected Jagged1 protein and mRNA expression levels in specimens (tongue cancer and adjacent tissues) from 74 patients with tongue cancer and in TSCC cell line. The Jagged1-targeted lentiviral vector RNAi system was constructed, and its suppressive effects on the proliferation and invasion of tongue carcinoma cells in in vivo and ex vivo were determined. RESULTS: Jagged1 was expressed in tongue squamous cell cancer tissues and cell line, but there were differences in its expression. Jagged1 was knocked down and the tumor growth was inhibited accompanying cell cycle changes. Animal studies also showed that the tumor growth was inhibited. CONCLUSIONS: Jagged1 may be involved in the differentiation and proliferation of tongue cancer. Targeting Jagged1 RNA interference lentiviral vector can effectively lower Jagged1 mRNA and protein expression levels of Tca8113 cells, thereby preventing the proliferation of TSCC cells. Jagged1 is expected to be a promising new target for curing tongue cancer. In-depth study of the interaction between Jagged1 and other molecules of Notch signaling pathway in the process of carcinogenesis has important theoretical guidance and clinical significance in revealing the mechanism of Jagged1 and its application in the therapy for tongue cancer.
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Proteínas de Ligação ao Cálcio/antagonistas & inibidores , Carcinoma de Células Escamosas/patologia , Proteínas de Membrana/antagonistas & inibidores , Neoplasias da Língua/patologia , Animais , Proteínas de Ligação ao Cálcio/genética , Carcinoma de Células Escamosas/genética , Técnicas de Cultura de Células , Ciclo Celular/genética , Diferenciação Celular/genética , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular/genética , Transformação Celular Neoplásica/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Técnicas de Silenciamento de Genes , Técnicas de Transferência de Genes , Vetores Genéticos/genética , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Proteína Jagged-1 , Lentivirus/genética , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Transplante de Neoplasias , Interferência de RNA , RNA Interferente Pequeno/genética , Proteínas Serrate-Jagged , Transdução de Sinais/genética , Neoplasias Cutâneas/patologia , Neoplasias da Língua/genéticaRESUMO
BACKGROUND: The relationship between autophagy and chemotherapy in cancer has been studied a lot recent years. However, there is currently no study on the role of autophagy in chemotherapy of adenoid cystic carcinoma (ACC) of human salivary glands. We hypothesized that autophagy plays a protective role for human salivary gland ACC cells during chemotherapy, diminishes the effect of treatment, and ultimately results in poor sensitivity to chemotherapy. MATERIALS AND METHODS: After inhibition of autophagy by 5 mM 3-methyladenine (3MA), 20 µM Chloroquine (CQ), or Beclin-1 shRNA, we examined the sensitivity of human salivary gland ACC cells to different concentrations of cis-diamminedichloroplatinum (CDDP) using MTT assay. Also, levels of autophagy in ACC cells treated by CDDP were assessed by western blot, GFP-LC3 fluorescence and transmission electron microscopy (TEM). RESULTS: Inhibition of autophagy induced by 3MA, CQ, or Beclin-1 shRNA could all enhance human salivary gland ACC cell death treated by CDDP. And, levels of autophagy in these cells showed a significant increase after treated by CDDP. CONCLUSION: Autophagy played a protective role for human salivary gland ACC cells during CDDP chemotherapy. Inhibition of autophagy in these cells could enhance cisplatin cytotoxicity-effects. These findings indicate a novel and promising way to reduce chemotherapy resistance and improve treatment outcome in human salivary gland ACC.
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Antineoplásicos/uso terapêutico , Autofagia/efeitos dos fármacos , Carcinoma Adenoide Cístico/tratamento farmacológico , Cisplatino/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Neoplasias das Glândulas Salivares/tratamento farmacológico , Adenina/análogos & derivados , Adenina/farmacologia , Proteínas Reguladoras de Apoptose/farmacologia , Proteína Beclina-1 , Carcinoma Adenoide Cístico/patologia , Técnicas de Cultura de Células , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cloroquina/farmacologia , Corantes , Proteínas de Fluorescência Verde , Humanos , Substâncias Luminescentes , Proteínas de Membrana/farmacologia , Proteínas Associadas aos Microtúbulos/análise , Neoplasias das Glândulas Salivares/patologia , Sais de Tetrazólio , TiazóisRESUMO
PURPOSE: This study investigated the application of a computer-aided design and manufacturing technique of defining tumor resection, fibula cutting, and positioning by surgical templates in mandibular reconstructive surgery. MATERIALS AND METHODS: Four patients who required mandibulectomy and simultaneous reconstruction were enrolled in this study. Preoperative surgical simulation was performed. The surgical templates that defined tumor resection, fibula cutting, and positioning were designed and fabricated. RESULTS: The surgeries were performed to the preoperative plan. All flaps survived. Superimposition of the postoperative image and the preoperative plan showed a satisfactory surgical accuracy. CONCLUSIONS: This method of defining tumor resection, fibula cutting, and positioning by surgical templates was accurate enough for mandibular reconstructive surgery.
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Simulação por Computador , Desenho Assistido por Computador , Neoplasias Mandibulares/cirurgia , Reconstrução Mandibular/métodos , Planejamento de Assistência ao Paciente , Adulto , Ameloblastoma/cirurgia , Placas Ósseas , Transplante Ósseo/métodos , Carcinoma de Células Escamosas/cirurgia , Condrossarcoma/cirurgia , Fíbula/cirurgia , Marcadores Fiduciais , Seguimentos , Neoplasias Gengivais/cirurgia , Sobrevivência de Enxerto , Humanos , Imageamento Tridimensional/métodos , Masculino , Doenças Mandibulares/cirurgia , Pessoa de Meia-Idade , Osteorradionecrose/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Retalhos Cirúrgicos/patologia , Tomografia Computadorizada Espiral/métodos , Sítio Doador de Transplante/cirurgia , Interface Usuário-ComputadorRESUMO
BACKGROUND: To investigate the efficacy and safety of endoscopic electrocoagulation haemostasis via a percutaneous transhepatic approach for the treatment of grade IV haemorrhagic cystitis (HC) after allogeneic haematopoietic stem cell transplantation (allo-HSCT) in children. METHODS: The clinical data of 14 children with severe HC, who were admitted to Hebei Yanda Hospital between July 2017 and January 2020, were analysed retrospectively. There were nine males and five females, with an average age of 8.6 years (range: 3 to 13 years). After an average of 39.6 (7 to 96) days of conservative treatment in the hospital's haematology department, the bladders of all patients were filled with blood clots. A small 2-cm incision was made in the suprapubic area to enter the bladder and quickly clear the blood clots, and a percutaneous transhepatic approach to electrocoagulation and haemostasis was performed. RESULTS: In the 14 children, a total of 16 operations were performed, with an average operation time of 97.1 (31 to 150) min, an average blood clot of 128.1 (80 to 460) mL and an average intraoperative blood loss of 31.9 (20 to 50) mL. There were three cases of postoperative bladder spasm remission after conservative treatment. During the follow-up period of 1 to 31 months, one patient improved after one operation, 11 patients were cured after one operation, and two patients were cured after recurrent haemostasis by secondary electrocoagulation, four of whom died of postoperative non-surgical blood-related diseases and severe lung infections. CONCLUSION: Percutaneous electrocoagulation haemostasis can quickly remove blood clots in the bladders of children after allo-HSCT with grade IV HC. It is a safe and effective minimally invasive treatment.
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Cistite , Transplante de Células-Tronco Hematopoéticas , Masculino , Feminino , Humanos , Criança , Estudos Retrospectivos , Hemorragia/etiologia , Hemorragia/terapia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Cistite/terapia , Cistite/cirurgia , EletrocoagulaçãoRESUMO
BACKGROUND: Although autophagy is universally involved in tumorigenesis and tumor progression, the roles of autophagy and autophagy-regulating genes in salivary gland adenoid cystic carcinoma (ACC) remain unknown. In this study, we investigated the expression of the autophagy-regulating genes Beclin-1, death-associated protein kinase-1, ultraviolet radiation resistance-associated gene, and phosphatase and tensin homolog in salivary gland ACC samples. METHODS: Immunohistochemistry and real-time polymerase chain reaction were used to analyze the expression of these genes in 89 ACC samples and normal salivary gland tissue samples. The relationship of their expression with clinicopathological features was analyzed. RESULTS: The data showed significantly lower expression of these genes in the tumor samples than in normal salivary gland tissue samples. Furthermore, Beclin-1 expression was significantly correlated with histological pattern of ACC (P<0.05), and high expression of ultraviolet radiation resistance-associated gene was associated with distant metastasis (P<0.05). Most importantly, univariate and multivariate survival analyses suggested that Beclin-1 protein and mRNA expression in cancer cells were independent prognostic indicators for ACC. CONCLUSION: Our results suggest that autophagy-regulating genes may participate in the pathogenesis of salivary gland ACC. Further research will be required to gain a better understanding of autophagy in ACC.
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Proteínas Reguladoras de Apoptose/análise , Autofagia/genética , Carcinoma Adenoide Cístico/patologia , Genes Supressores de Tumor , Proteínas de Membrana/análise , Neoplasias das Glândulas Salivares/patologia , Proteínas Reguladoras de Apoptose/genética , Proteína Beclina-1 , Proteínas Quinases Dependentes de Cálcio-Calmodulina/análise , Proteínas Quinases Dependentes de Cálcio-Calmodulina/genética , Carcinoma Adenoide Cístico/genética , Carcinoma Adenoide Cístico/secundário , Núcleo Celular/ultraestrutura , Citoplasma/ultraestrutura , Proteínas Quinases Associadas com Morte Celular , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Metástase Linfática/patologia , Masculino , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , PTEN Fosfo-Hidrolase/análise , PTEN Fosfo-Hidrolase/genética , Neoplasias Parotídeas/genética , Neoplasias Parotídeas/patologia , Prognóstico , Ductos Salivares/patologia , Neoplasias das Glândulas Salivares/genética , Glândulas Salivares Menores/patologia , Proteínas Supressoras de Tumor/análise , Proteínas Supressoras de Tumor/genéticaRESUMO
PURPOSE: In this study we tried to define tumor resection, fibula cutting, and positioning by surgical templates to perform the mandible reconstruction surgery according to the preoperative simulation. The accuracy was evaluated through cadaveric surgery. MATERIALS AND METHODS: Five cadaveric mandibles and fibulas were obtained. Preoperative surgical simulation was performed. Surgical templates that defined tumor resection, fibula cutting, and positioning were designed and fabricated. Translation, angular deviation, and rotation of bone grafts, as well as translation of condyles, were measured. RESULTS: The reconstructed mandibles showed high similarity to the surgical planning. The mean translation, angular deviation, and rotation of fibula segments of the reconstructed mandibles were 1.35 ± 0.86 mm, 3.36° ± 1.86°, and 8.13° ± 5.35°, respectively. In the mandible remnants, the translation of condyles was measured, with a mean of 1.39 ± 0.66 mm. CONCLUSIONS: Our method of defining the tumor resection, fibula cutting, and positioning by surgical templates was accurate enough for mandible reconstruction surgery.
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Simulação por Computador , Mandíbula/cirurgia , Neoplasias Mandibulares/cirurgia , Modelos Anatômicos , Procedimentos de Cirurgia Plástica , Cirurgia Assistida por Computador/métodos , Transplante Ósseo , Cadáver , Fíbula/cirurgia , Retalhos de Tecido Biológico , Humanos , Imageamento Tridimensional , Mandíbula/diagnóstico por imagem , Côndilo Mandibular/cirurgia , Planejamento de Assistência ao Paciente , Período Pré-Operatório , Tomografia Computadorizada EspiralRESUMO
BACKGROUND: Involvement of Notch signaling in several tumors is well known, but its role in tongue squamous cell carcinoma remains poorly characterized. The purpose of this study was to evaluate the roles of Notch signaling in the oncogenesis of tongue carcinoma. MATERIALS AND METHODS: Tumor specimens and adjacent non-neoplastic tongue tissues from 74 patients with tongue carcinoma and human tongue carcinoma cell line Tca8113 were examined using immunohistochemistry and RT-PCR to determine the expressions of Notch1, Notch3, Jagged1, and Jagged2. RESULTS: The mRNA expressions of Notch1, Notch3, Jagged1, and Jagged2 were detected in Tca8113, tongue carcinoma, and adjacent non-neoplastic tongue tissues. The expression levels of mRNAs in tongue carcinoma were higher than those in adjacent non-neoplastic tongue tissues (P < 0.05). Immunohistochemical examination showed that the Notch signal molecules were expressed in Tca8113, tongue carcinoma, and adjacent non-neoplastic tongue tissues. The expression rates of Notch1 and Notch3 protein in tongue carcinoma were higher than those in adjacent non-neoplastic tongue tissues (χ² = 6.10, P = 0.013; χ² = 3.94, P = 0.047). Notch1 and jagged1 were significantly more highly expressed in lymph node metastasis-positive tongue carcinoma (χ² = 6.108, P = 0.013; χ² = 7.354, P = 0.025). In addition, expressions of Notch3 and Jagged2 were highly correlated in tongue carcinoma tissues (χ² = 42.130, P < 0.001). CONCLUSIONS: Expressions of Notch receptors and ligands in tongue carcinoma and adjacent non-neoplastic tongue tissues suggest that Notch signaling may control cell differentiation and proliferation of carcinoma cells. The disorder of Notch signaling may be a mechanism of the tongue carcinoma development.
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Carcinoma de Células Escamosas/metabolismo , Receptores Notch/metabolismo , Transdução de Sinais/fisiologia , Neoplasias da Língua/metabolismo , Língua/metabolismo , Adulto , Idoso , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Estudos de Casos e Controles , Linhagem Celular Tumoral , Feminino , Humanos , Imuno-Histoquímica , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Proteína Jagged-1 , Proteína Jagged-2 , Metástase Linfática , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Pessoa de Meia-Idade , RNA Mensageiro/análise , Receptor Notch1/genética , Receptor Notch1/metabolismo , Receptor Notch3 , Receptores Notch/genética , Valores de Referência , Sistemas do Segundo Mensageiro/genética , Sistemas do Segundo Mensageiro/fisiologia , Proteínas Serrate-Jagged , Transdução de Sinais/genética , Neoplasias da Língua/genética , Neoplasias da Língua/patologiaRESUMO
BACKGROUND: The aim of this study was to evaluate the roles of Notch signaling in the oncogenesis and cytodifferentiation of cemento-ossifying fibroma, the expressions of Notch receptors and ligands were detected in COF and normal jaw bones. MATERIALS AND METHODS: The expressions of Notch1, Notch3, Jagged1, and Jagged2 were detected by reverse transcriptase polymerase chain reaction and immunohistochemistry respectively in 16 cases of normal bone tissues and 12 cases of COF of the jaws. RESULTS: The mRNAs expressions of Notch1, Notch3, Jagged1, and Jagged2 were detected in all specimens. The expression levels of mRNAs in COF were higher than those in normal bones. In COF, Notch proteins staining were showed extensively distribution in fibroblasts and osteoblasts. In normal bone tissue, Notch proteins were expressed in osteoblasts, whereas proteins staining were weaker than those in COF, but no detection in fibroblast-like bone marrow stroma cells. The expressions of Notch receptors and ligands were not detected in cementum-like products or bone matrices. CONCLUSION: Our data suggest that Notch signaling may participate in controlling cell differentiation and proliferation in normal bone and COF of the jaws. Notch signaling disorder may be a molecular incident in COF occurrence and development.
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Proteínas de Ligação ao Cálcio/análise , Peptídeos e Proteínas de Sinalização Intercelular/análise , Neoplasias Maxilomandibulares/patologia , Proteínas de Membrana/análise , Tumores Odontogênicos/patologia , Receptor Notch1/análise , Receptores Notch/análise , Células da Medula Óssea/patologia , Matriz Óssea/patologia , Diferenciação Celular , Proliferação de Células , Transformação Celular Neoplásica/patologia , Cemento Dentário/patologia , Fibroblastos/patologia , Humanos , Proteína Jagged-1 , Proteína Jagged-2 , Arcada Osseodentária/patologia , Osteoblastos/patologia , Receptor Notch3 , Proteínas Serrate-Jagged , Células Estromais/patologiaRESUMO
PURPOSE: The management of large hilar calculi is a technically challenging issue during sialoendoscopic surgery. The aim of the present study was to evaluate the clinical efficacy of sialoendoscopically assisted open sialolithectomy for the removal of large submandibular hilar calculi to avoid sialoadenectomy. PATIENTS AND METHODS: The present study was undertaken among patients with sialolithiasis scheduled for sialoendoscopic surgery from August 2005 to October 2008. When we failed to remove large submandibular hilar stones intraductally, we performed sialoendoscopically assisted open sialolithectomy. The clinical characteristics, pre- and intraoperative data, and outcomes were documented in a prospective fashion. RESULTS: Of 78 consecutive patients with submandibular sialolithiasis, 18 were treated with sialoendoscopically assisted open sialolithectomy immediately after failure of intraductal removal of calculi by sialoendoscopy. For 17 patients, large hilar sialoliths were successfully removed using this surgical technique. The surgery failed in 1 patient with multiple sialoliths, and the procedure was converted to open sialoadenectomy. Temporary numbness of the tongue for 1 week postoperatively was documented in 3 patients. The patients were followed up for a median period of 18 months without any symptoms or signs of recurrence. CONCLUSION: Our results suggest that sialoendoscopically assisted open sialolithectomy is an effective and safe surgical technique to remove large submandibular hilar calculi.
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Endoscopia , Cálculos dos Ductos Salivares/cirurgia , Doenças da Glândula Submandibular/cirurgia , Adulto , Endoscópios , Feminino , Humanos , Procedimentos Cirúrgicos Minimamente Invasivos , Procedimentos Cirúrgicos Bucais/métodos , Cuidados Pós-Operatórios , Complicações Pós-Operatórias , StentsRESUMO
PURPOSE: Traditionally, sialoadenectomy was always indicated when open sialolithectomy failed. The aim of the present study was to investigate the role of sialoendoscopy as the secondary intervention after failure of open sialolithectomy. PATIENTS AND METHODS: A consecutive series of 15 patients with obstructive salivary gland disease with failure of open sialolithectomy were prospectively recruited for our study. All these patients underwent sialoendoscopy under local anesthesia. The reasons for the failure of open sialolithectomy were analyzed, and secondary interventions were performed using sialoendoscopy. RESULTS: Failure of open sialolithectomy resulted from 4 main causes. Small stones could not be found after the duct was incised (n = 3); the stones were pushed posteriorly during open surgery (n = 4); the stones located in the anterior part of the duct were removed, but the hilar stones were left untouched (n = 5); and radiolucent stones were missed (n = 3). All the patients were treated successfully by sialoendoscopy. No symptoms or signs of recurrence developed during a median follow-up period of 16 months. CONCLUSIONS: Sialoendoscopy can be recommended as an effective secondary intervention after failure of open sialolithectomy.
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Endoscopia do Sistema Digestório , Cálculos das Glândulas Salivares/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reoperação/métodos , Ductos Salivares/cirurgia , Falha de Tratamento , Adulto JovemRESUMO
As a conceivable route to achieving anthropological carbon looping, carbon capture and utilization (CCU) technologies employ waste CO2 as an accessible C1 building block to generate upgraded chemicals or fuels, thereby simultaneously remedying environmental issues and energy crises. However, efficient CO2 conversion is disfavored by both its thermodynamics and its kinetics. Heterostructured materials with well-controlled interfaces have great potential for enhanced catalytic performance in various CO2 transformation reactions, owing to the synergistic effects among components, numerous interfacial and/or surface active sites, increased CO2 adsorption capacity, promoted charge transfer efficiency, and unique physicochemical properties. This Review highlights the state of the art in typical heterostructures, such as core-shell, yolk-shell, Janus, hierarchical (branched and hollow), and 2D/2D layered structures, applied for CO2 conversion with various energy inputs (radiation, electricity, heat). Fabrication methods of different heterostructures and structure-composition-performance relationships are also discussed concisely. Finally, a brief summary and prospective research directions are provided. The motivation of this Review is to offer instructive information on the applicability of inorganic heterostructures for CO2 transformation reactions, and it is hoped that further enlightening studies in this field could emerge in the future.
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The facile synthesis of highly ordered mesoporous aluminas with high thermal stability and tunable pore sizes is systematically investigated. The general synthesis strategy is based on a sol-gel process associated with nonionic block copolymer as templates in ethanol solvent. Small-angle XRD, TEM, and nitrogen adsorption and desorption results show that these mesoporous aluminas possess a highly ordered 2D hexagonal mesostructure, which is resistant to high temperature up to 1000 degrees C. Ordered mesoporous structures with tunable pore sizes are obtained with various precursors, different acids as pH adjustors, and different block copolymers as templates. These mesoporous aluminas have large surface areas (ca. 400 m2/g), pore volumes (ca. 0.70 cm3/g), and narrow pore-size distributions. The influence of the complexation ability of anions and hydro-carboxylic acid, acid volatility, and other important synthesis conditions are discussed in detail. Utilizing this simple strategy, we also obtained partly ordered mesoporous alumina with hydrous aluminum nitrate as the precursor. FTIR pyridine adsorption measurements indicate that a large amount of Lewis acid sites exist in these mesoporous aluminas. These materials are expected to be good candidates in catalysis due to the uniform pore structures, large surface areas, tunable pore sizes, and large amounts of surface Lewis acid sites. Loaded with ruthenium, the representative mesoporous alumina exhibits reactant size selectivity in hydrogenation of acetone, D-glucose, and D-(+)-cellobiose as a test reaction, indicating the potential applications in shape-selective catalysis.
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Óxido de Alumínio/síntese química , Temperatura , Óxido de Alumínio/química , Cristalização , Etanol/química , Géis/química , Temperatura Alta , Tamanho da Partícula , Porosidade , Reprodutibilidade dos Testes , Propriedades de SuperfícieAssuntos
Histiocitoma Fibroso Benigno/patologia , Mandíbula/cirurgia , Neoplasias Mandibulares/patologia , Reconstrução Mandibular/métodos , Adulto , Transplante Ósseo , Histiocitoma Fibroso Benigno/diagnóstico por imagem , Histiocitoma Fibroso Benigno/cirurgia , Humanos , Masculino , Neoplasias Mandibulares/diagnóstico por imagem , Neoplasias Mandibulares/cirurgia , Reconstrução Mandibular/instrumentação , Antígeno Nuclear de Célula em Proliferação/análise , Radiografia PanorâmicaRESUMO
OBJECTIVE: To explore the effects of adrenomedullin (ADM) on Angiotensin II (AngII)-induced collagen synthesis in cultured rat vascular adventitial fibroblasts. METHODS: Rat vascular adventitial fibroblasts were cultured in vitro. ADM produced and secreted from adventitia in the presence of AngII was detected by radioimmunoassay, type I, III collagen contents in adventitia fibroblasts were measured by ELISA and the expressions of TGFbeta1 and MMP-2 were determined by RT-PCR and Western blotting. RESULTS: AngII significantly induced ADM secretion in adventitial fibroblasts in a dose-dependent manner. These effects could be reduced by 45%, 3% and 46%, through pre-treatment with Losartan, PD123319 or both, respectively for 30 min in culture medium. The AngII-induced type I, III collagen secretion in adventitial fibroblasts was significantly reduced by AMD in a dose-dependent manner, (P < 0.01) while ADM agonist ADM(22 - 52) significantly potentiated the effect of AngII; ADM also reduced AngII-induced expression of TGFbeta1 at mRNA and protein levels in a dose-dependent manner. AngII reduced the expression of MMP-2 at mRNA and protein levels in adventitial fibroblasts and these effects could be reversed by AMD (10(-8) mol/L). CONCLUSION: AngII stimulated ADM secretion in adventitia fibroblasts, ADM in turn can inhibit AngII-induced type I, III collagen synthesis in adventitial fibroblasts probably by downregulating the TGFbeta1 expression and upregulating MMP-2 expression. ADM therefore served as an antifibrotic factor in vascular remodeling process.
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Adrenomedulina/metabolismo , Angiotensina II/metabolismo , Colágeno Tipo I/biossíntese , Fibroblastos/metabolismo , Animais , Células Cultivadas , Matriz Extracelular/metabolismo , Regulação da Expressão Gênica , Masculino , Metaloproteinase 2 da Matriz/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Fator de Crescimento Transformador beta/metabolismoRESUMO
Abnormal expression of ß-catenin contributes to tumor development, progression, and metastasis in various cancers. However, little is known about the relationship between abnormal expression of ß-catenin and cisplatin chemotherapy in oral squamous cell carcinoma (OSCC). The present study aimed to investigate the effect of ß-catenin on OSCC cisplatin resistance and evaluated the drug susceptibility of stable cell lines with ß-catenin knockin and knockdown. In this study, we found that higher expression level of ß-catenin can be observed in CDDP-treated cell lines as compared with the control group. Furthermore, the expression levels of ß-catenin increased in both a concentration- and time-dependent manner with the cisplatin treatment. More importantly, the nuclear translocation of ß-catenin could also be observed by confocal microscope analysis. Stable cell lines with CTNNB1 knockin and knockdown were established to further investigate the potential role and mechanism of ß-catenin in the chemoresistance of OSCC in vitro and in vivo. Our findings indicated that overexpression of ß-catenin promoted cisplatin resistance in OSCC in vitro and in vivo. We confirmed that GSK-3ß, C-myc, Bcl-2, P-gp, and MRP-1 were involved in ß-catenin-mediated drug resistance. Our findings indicate that the Wnt/ß-catenin signaling pathway may play important roles in cisplatin resistance in OSCC.
Assuntos
Carcinoma de Células Escamosas/metabolismo , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica , Neoplasias Bucais/metabolismo , Proteínas de Neoplasias/metabolismo , beta Catenina/biossíntese , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Humanos , Neoplasias Bucais/tratamento farmacológico , Neoplasias Bucais/genética , Neoplasias Bucais/patologia , Proteínas de Neoplasias/genética , Via de Sinalização Wnt/efeitos dos fármacos , Via de Sinalização Wnt/genética , beta Catenina/genéticaRESUMO
Single-crystalline and uniform nanopolyhedra, nanorods, and nanocubes of cubic CeO2 were selectively prepared by a hydrothermal method at temperatures in the range of 100-180 degrees C under different NaOH concentrations, using Ce(NO3)3 as the cerium source. According to high-resolution transmission electron microscopy, they have different exposed crystal planes: {111} and {100} for polyhedra, {110} and {100} for rods, and {100} for cubes. During the synthesis, the formation of hexagonal Ce(OH)3 intermediate species and their transformation into CeO2 at elevated temperature, together with the base concentration, have been demonstrated as the key factors responsible for the shape evolution. Oxygen storage capacity (OSC) measurements at 400 degrees C revealed that the oxygen storage takes place both at the surface and in the bulk for the as-obtained CeO2 nanorods and nanocubes, but is restricted at the surface for the nanopolyhedra just like the bulk one, because the {100}/{110}-dominated surface structures are more reactive for CO oxidation than the {111}-dominated one. This result suggests that high OSC materials might be designed and obtained by shape-selective synthetic strategy.
Assuntos
Cério/química , Nanoestruturas/química , Oxigênio/química , Temperatura , Cristalização , Microscopia Eletrônica de Transmissão , Nanoestruturas/ultraestrutura , Nanotubos/química , Nanotubos/ultraestrutura , Hidróxido de Sódio/químicaRESUMO
OBJECTIVE: To investigate the changes in plasma urotensin II(U II) expression levels in patients with coronary heart disease (CHD). METHODS: Plasma U II levels in 50 CHD patients with coronary stenosis indicated by coronary angiography and 20 healthy subjects were determined by radio immunoassay. RESULTS: Venous plasma U II levels were significantly lowered in CHD patients in comparison with the healthy subjects (1.61+/-1.02 pg/ml vs 3.70+/-1.30 pg/ml, P=0.000). In the CHD patient group, significantly differences were noted in the U II levels between patients with stable angina (2.62+/-1.20 pg/ml), unstable angina (1.39+/-0.80 pg/ml) and acute myocardial infarction (AMI, 1.04+/-0.45 pg/ml, P=0.004). CHD patients with coronary artery occlusion and those with only coronary stenosis had comparable venous plasma U II levels (1.29+/-1.02 pg/ml vs 1.76+/-1.00 pg/ml, P=0.131), whereas the patients with restenosis after percutaneous transluminal coronary angioplasty (PTCA) had higher U II levels than the other subjects in the CHD patient group (2.28+/-0.94 pg/ml vs 1.40+/-0.96 pg/ml, P=0.008), and the femoral plasma U II levels were significantly elevated after PTCT, increasing from 1.18+/-1.14 pg/ml to a postoperative level of 2.22+/-1.77 pg/ml (P=0.001). CONCLUSION: U II might play a role in the pathophysiological process of CHD and can be involved in the restenosis after angioplasty.