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The utilization of thermodynamically favorable sulfur oxidation reaction (SOR) as an alternative to sluggish oxygen evolution reaction is a promising technology for low-energy H2 production while degrading the sulfur source from wastewater. Herein, amorphous/crystalline S-doped Pd nanosheet arrays on nickel foam (a/c S-Pd NSA/NF) is prepared by S-doping crystalline Pd NSA/NF. Owing to the ultrathin amorphous nanosheet structure and the incorporation of S atoms, the a/c S-Pd NSA/NF provides a large number of active sitesand the optimized electronic structure, while exhibiting outstanding electrocatalytic activity in hydrogen evolution reaction (HER) and SOR. Therefore, the coupling system consisting of SOR-assisted HER can reach a current density of 100 mA cm-2 at 0.642 V lower than conventional electrolytic water by 1.257 V, greatly reducing energy consumption. In addition, a/c S-Pd NSA/NF can generate H2 over a long period of time while degrading S2- in water to the value-added sulfur powder, thus further reducing the cost of H2 production. This work proposes an attractive strategy for the construction of an advanced electrocatalyst for H2 production and utilization of toxic sulfide wastewater by combining S-doping induced partial amorphization and ultrathin metal nanosheet arrays.
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Designing two-dimensional (2D) materials functionalized with organic molecules is an effective tactic to enhance catalytic performances for the oxygen reduction reaction (ORR). Herein, we synthesize Pd metallene with in situ modification of polyethylenimine-ethylenediamine (Pd@PEI-EDA metallene), in which PEI-EDA serves as both the structure-directing agent and modifier. Pd@PEI-EDA metallene has ample active sites and tuneable electronic structures due to ultrathin nanosheets with abundant wrinkles and interfacial structure. In contrast with commercial Pd/C and Pt/C, Pd@PEI-EDA metallene displays preferable catalytic ORR performance under alkaline conditions. This work offers an in situ interface engineering tactic for the preparation of 2D polymer-metal electrocatalysts to boost the ORR performance.
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The design of electrocatalysts with excellent activity and stability for overall water splitting is highly desirable, and remains a challenge. Constructing heterojunctions onto the same substrate is beneficial for the integration of a water-splitting reaction. Herein, self-supported IrNi/Ni(OH)2@PPy and IrNi/Ni(OH)2@FeOOH are fabricated by coupling polypyrrole (PPy) and iron oxyhydroxide (FeOOH) on IrNi/Ni(OH)2nanosheets array, respectively. Benefiting from the nanosheet structure, composition, and heterogeneous interface, the as-constructed IrNi/Ni(OH)2@PPy and IrNi/Ni(OH)2@FeOOH catalysts can efficiently drive the hydrogen evolution reaction and oxygen evolution reaction, respectively. Moreover, the electrolyzer consisting of IrNi/Ni(OH)2@PPy and IrNi/Ni(OH)2@FeOOH for water splitting requires only a low cell voltage of 1.49 V to deliver 10 mA cm-2. This study provides a useful strategy for constructing efficient electrocatalysts by synergistic composition modulation and interface engineering.
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OBJECTIVES: To assess the diagnostic value of qualitative and quantitative contrast-enhanced ultrasound (CEUS) for pathological subtypes of small solid renal masses (sSRMs). METHODS: Patients with sSRMs confirmed by surgical pathology from January 2019 to November 2021 were retrospectively identified. All patients were divided into 3 groups: clear cell renal cell carcinoma (ccRCC) group, none-ccRCC group (renal cell carcinoma other than ccRCC), and angiomyolipoma (AML) group. The mass position, size, echogenicity and blood flow signals were compared. The speed of wash-in, wash-out, the degree of peak enhancement and the homogeneity at peak enhancement, the presence of pseudocapsule sign in CEUS imaging were qualitatively evaluated. Peak enhancement, wash-in area under the curve (WiAUC), rise time, time to peak, wash-in rate (WiR), wash-in perfusion index (WiPI) and tumor-to-cortex enhancement ratio of the above parameters in CEUS imaging were quantitatively evaluated. RESULTS: Of 105 patients, 105 sSRMs (66 ccRCC, 18 none-ccRCC, 21 AML) were enrolled in this study. No significant differences were found on location, size and echogenicity among 3 groups (all P > .05). The proportion of fast-washout and hypo-enhancement were highest in none-ccRCC group. Heterogeneous enhancement was detected in 87.88% in ccRCC group which is significantly higher than other 2 groups. Hundred percent of the AML showed no pseudocapsule sign, which is the highest among the 3 groups. Peak enhancement, WiAUC, WiR, WiPI of ccRCC group were the highest among the 3 groups. CONCLUSIONS: Qualitative and quantitative CEUS not only has the diagnostic value in distinguishing AML from malignant sSRMs, but also helps to differentiate the pathological subtypes of sSRMs.
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Angiomiolipoma , Carcinoma de Células Renais , Neoplasias Renais , Leucemia Mieloide Aguda , Humanos , Carcinoma de Células Renais/diagnóstico por imagem , Estudos Retrospectivos , Meios de Contraste , Neoplasias Renais/diagnóstico por imagem , Ultrassonografia/métodos , Angiomiolipoma/diagnóstico por imagem , Angiomiolipoma/patologiaRESUMO
BACKGROUND: The male sling has emerged as a minimally invasive option for incontinence after prostate treatment (IPT) in recent years, but it has not yet been introduced into China. This study retrospectively evaluated the clinical outcomes of the modified female mid-urethral sling in the treatment of IPT and explored potential preoperative factors to better predict surgical outcomes. METHODS: From May 2014 to January 2021, a total of 70 patients with IPT who underwent transobturator male sling procedure using the modified female mid-urethral sling were retrospectively reviewed. All surgeries were performed by a single surgeon. Functional outcomes were evaluated by daily pad usage, and the severity of incontinence was classified as mild (≤2 pads), moderate (3-4 pads), or severe (≥5 pads). Success was defined as no pad usage or 1 pad for safety (cure), or a reduction in daily pad use by >50% (improved). Patients were followed up at 3, 6 months, and yearly thereafter. RESULTS: At a final follow-up of 6-80 months, 35 (50.0%) patients were cured, 12 (17.1%) were improved, and 23 (32.9%) were still incontinent. There was a slight trend of declining continence over time, and the majority of patients remained improved. During follow-up, 25 patients had perineal or scrotal pain, five patients had voiding difficulty and two had de novo urgency, one developed infection and underwent sling explantation. Early urinary retention was the only significant factor linked to better surgical outcomes. CONCLUSION: The modified female mid-urethral sling represents a viable option for the treatment of IPT. Improved efficacy is seen in patients with a history of early postoperative urinary retention.
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Slings Suburetrais , Incontinência Urinária por Estresse , Incontinência Urinária , Retenção Urinária , Feminino , Seguimentos , Humanos , Masculino , Próstata , Prostatectomia/métodos , Estudos Retrospectivos , Slings Suburetrais/efeitos adversos , Resultado do Tratamento , Incontinência Urinária/etiologia , Incontinência Urinária/cirurgia , Incontinência Urinária por Estresse/etiologia , Incontinência Urinária por Estresse/cirurgia , Retenção Urinária/etiologia , Retenção Urinária/cirurgiaRESUMO
Tailoring the morphology and crystal structure of metallene is critical to improve its electrocatalytic performance. In this work, hetero-phase RhB metallene (h-RhB metallene) with amorphous/crystalline structure is readily prepared by a two-step method. The h-RhB metallene is very unique in its non-metallic heteroatom doping and amorphous/crystalline structure. Benefiting from the unique metallene structure and the optimized electronic states induced by the incorporation of B atoms, the h-RhB metallene exhibits superior performance for hydrogen evolution reaction and hydrogen peroxide electro-oxidation reaction (HPOR). When coupled with HPOR, the h-RhB metallene||h-RhB metallene water electrolysis two-electrode system exhibits a lower cell voltage of 0.379 V (@ 10 mA cm-2 ) compared with the overall water splitting (1.35 V). The presented synthetic method provides a powerful strategy to design metallene with hetero-phase for energy-saving H2 production.
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Boro , Água , Eletrólise/métodos , Peróxido de Hidrogênio/química , Oxirredução , Água/químicaRESUMO
The compositional and structural engineering of advanced nanomaterials for hydrogen evolution reaction (HER) is highly necessary for efficient hydrogen production. Herein, PdOs nanospine assemblies (PdOs NAs) with urchin-like structures are fabricated via one-step route using DM-970 and KBr as surfactant agent and capping agent, respectively. Benefiting from electronic effect and multi-branched structure, the PdOs NAs exhibit superior performance for HER in alkaline and neutral solutions, requiring overpotentials of 28 and 35 mV at -10 mA cm-2, respectively, as well as superior long-term stability. This study offers a universal approach for the fabrication of active Pd-based catalysts with multi-branched morphology for efficient water electrolysis and beyond.
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Interface engineering of two-dimensional (2D) materials by conductive polymer modification is one of the valid methods to promote hydrogen evolution reaction (HER) performance. Herein, we report a simple and universal strategy for the synthesis of polypyrrole (PPy) modified Rh metallene (Rh@PPy metallene) towards an efficient pH-universal HER. Due to the unique ultrathin 2D metallene structure and the optimized electronic structure between the metallene-PPy surfaces, the as-prepared Rh@PPy metallene not only exhibits excellent HER activity with low overpotentials of 16, 39 and 42 mV in 0.5 M H2SO4, 1 M KOH, and 1 M phosphate buffer solution at current density of 10 mA cm-2, but also displays outstanding stability and durability. This work provides a well-founded pathway to constructe metallene-organic interfaces for various electrocatalytic applications.
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Nonmetal doping is a promising strategy to improve electrocatalytic performance of noble metal based catalysts for oxygen reduction reaction (ORR). Herein, we report a facile method to fabricate PdCuBP nanothorn assemblies (PdCuBP NTAs) by co-doping B and P into pre-synthesized PdCu NTAs using NaBH4and NaH2PO2as B source and P source, respectively. The metal-nonmetal structure and multi-branched morphology can optimize oxygen adsorption energy and avoid catalyst migration, agglomeration and Ostwald ripening. As such, the obtained PdCuBP NTAs exhibit efficient activity and excellent long-term stability for ORR. This research offers an excellent strategy for co-doping nonmetal elements into metal nanocrystals with controllable composition and structure to improve electrocatalytic ORR performance.
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Exploring cost-effective and highly active electrocatalysts is of great significance for sustainable electrochemical NH3synthesis. Palladium (Pd)-based catalysts have been unanimously considered as one of the most efficient catalysts for the nitrogen reduction reaction (NRR). Herein, self-supported mesoporous Pd film with partial oxidation on Ni foam (mPd-PdO/NF) was synthesized through the micelle-assisted chemical replacement method coupled with air oxidation under 260 °C, and the mPd-PdO/NF electrocatalyst exhibited superior NRR performance with the maximum values ofrNH3(24.8 mg h-1mgcat.-1) and FE (16.64%) were obtained at -0.1 V, relative to the single counterparts (mPd/NF and mPdO/NF). It is proposed that both metallic Pd and its oxide domains when co-existing with a phase boundary between them can facilitate nitrogen activation and hydrogenation, resulting in an enhanced NRR performance. This work provides an inspiring strategy for the rational design of highly active and durable metal-metal-oxide nanoarchitectonics for ammonia electrosynthesis.
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BACKGROUNDS: As a regulator of cell cycle, cell division cycle-associated 5 (CDCA5) is involved in the progression of various malignant tumors. However, the potential relationship between CDCA5 and lung cancer has not been reported. METHODS: In our study, we analyzed the expression of CDCA5 in a variety of malignant tumors, performed Kaplan-Meier survival analysis of lung adenocarcinoma (LUAD), explored the potential relationship between CDCA5 expression and clinicopathological characteristics, assessed the predictive capability of at different stages of clinicopathological characteristics, revealed the enriched functions and signaling pathways among LUAD paitents with high CDCA5 expression, and investigated the correlation between PD-1, PD-L1, and CDCA5 through bioinformatics analyses. Subsequently, we performed quantitative real-time reverse transcription-polymerase chain reaction (qRT-PCR) and western blotting (WB) to demonstrate that CDCA5 mediates the p53-p21 pathway and regulates the cell cycle. RESULT: CDCA5 is probably involved in the occurrence and development of NSCLC, and function as a reliable biomarker for predicting the survival outcomes of patients with early stage of patients with LUAD. Furthermore, CDCA5 may be a promising indicator of immunotherapy efficacy. In addition, silencing the expression of CDCA5 significantly increased the proportion of apoptotic NSCLC cells, and caused NSCLC cells to be arrested in the G1 phase. CONSLUSION: In conclusion, CDCA5 regulated the cell cycle of NSCLC cells by mediating the p53-p21 signaling pathway, participating in the development and progression of NSCLC patients.
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Proteínas Adaptadoras de Transdução de Sinal , Adenocarcinoma de Pulmão , Carcinoma Pulmonar de Células não Pequenas , Proteínas de Ciclo Celular , Neoplasias Pulmonares , Proteínas Adaptadoras de Transdução de Sinal/genética , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/patologia , Apoptose/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Ciclo Celular/genética , Proteínas de Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células , Fase G1 , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Oncogenes , Transdução de Sinais/genética , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismoRESUMO
BACKGROUND: Pancreatic cancer (PC) is one of the deadliest malignant tumors with poor prognosis. DNA repair genes can be promising candidate biomarkers in PC. The aim of this study was to generate and clinically validate a novel gene signature to effectively predict the prognosis of patients with PC. METHODS: The PC-related data of cancer genome atlas database and the GSE62452, GSE85916 of the gene expression omnibus database were downloaded for signature and further validation. According to the risk score, Patients were classified into high and low risk score groups. We analyzed drug sensitivity base on genomics of drug sensitivity in cancer and immune cell infiltration via CIBERSORT between the two groups. Gene set variation Analysis was performed to analyze signaling pathways affecting prognosis. RESULTS: Nine genes (F5, CD36, TRIM29, VCAM1, ANO1, ERBB3, MMP28, NEK2 and MET) were identified to construct a prognostic model. Patients with lower risk score had significantly favorable overall survival in the TCGA database, GSE62452 and GSE85916 dataset (p < 0.05). GSVA analysis showed differences in 13 important signaling pathways between high and low risk score groups. Immune-modulating factors (ADORA2A, CD160, KDR, BTLA) were highly expressed in the low-risk group. The risk score significantly affected the sensitivity of patients to Gefitinib and Dasatinib (p < 0.005) and associated with overall survival and grade (p < 0.05). CONCLUSION: This study evaluated a potential prognostic signature base on nine DNA repair genes and provides a way to explore the mechanism of DNA repair genes and immunotherapy in pancreatic cancer.
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Neoplasias Pancreáticas , Reparo do DNA/genética , Proteínas de Ligação a DNA/genética , Humanos , Imunoterapia , Quinases Relacionadas a NIMA/genética , Quinases Relacionadas a NIMA/metabolismo , Neoplasias Pancreáticas/patologia , Prognóstico , Fatores de Transcrição/genéticaRESUMO
Tuning the composition and surface structure of the metal nanocrystals offered viable avenues for enhancing catalytic performances. Herein, we report a facile one-pot strategy for the formation of PdAg porous alloy nanostructures (PANs) with a concave surface. Due to their highly open nanostructures and tunable d-band center features, PdAg PANs exhibit superior electrocatalytic activity and long-term durability than Pd nanoparticles (NPs) and Pd/C for methanol oxidation reaction (MOR) in alkaline media. Our results provide a feasible and efficient approach for the controlled synthesis of high-performance Pd-based nanomaterials for alkaline MOR.
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The aim of the current study was to establish a simple method for effectively inducing memory T lymphocytes by the intraperitoneal injection of spleen lymphocytes into mice. In total, 75 mice were divided into the following groups: an injection group administered three doses of spleen lymphocytes (1 × 106 , 5 × 106 , and 1 × 107 cells), a transplantation group in which a 0.25-cm2 skin section from C57BL/6 mice was transplanted onto the back of the recipient, and a control group in which an equal volume of phosphate-buffered saline was injected. At 1, 2, or 3 months following transplantation, the following parameters were evaluated: quantity of T lymphocytes, percentage of cluster of differentiation 8+ (CD8+ ) memory T cells, and proliferation index of purified CD8+ memory T cells. No significant differences among groups were detected at 1 month (p > .05). However, the injection group administered 1 × 106 cells exhibited the highest proportion of CD8+ memory T cells among all groups at 2 months, and the proportions of CD8+ T cells were higher in the three injection groups than in the skin transplantation and control groups at 3 months. The proportions of memory T cells were higher in the injection groups administered 5 × 106 or 1 × 107 cells than in the skin transplantation and control groups at 3 months. The newly established method effectively induces memory T lymphocytes via the intraperitoneal injection of spleen lymphocytes in vivo and has potential applications in the field of immunotherapy.
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Linfócitos T CD8-Positivos , Linfócitos/imunologia , Células T de Memória , Animais , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/imunologia , Feminino , Injeções Intraperitoneais , Transfusão de Linfócitos , Células T de Memória/citologia , Células T de Memória/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Transplante de Pele , Baço/citologiaRESUMO
OBJECTIVE: To evaluate the effect of the York-Mason procedure (posterior sagittal approach) in the treatment of urethrorectal fistula. METHODS: Ten 15ï¼80 (mean 54) years old male patients with urethrorectal fistula were treated by the York-Mason procedure, 3 by anoplasty for congenital anal atresia, 5 by laparoscopic radical prostatectomy, and the other 2 by radical rectal cancer resection. All the cases were single fistula with a history of 3 months to 18 years. Enterostomy was performed in 6 of the cases before the York-Mason procedure. RESULTS: The York-Mason procedure lasted 90ï¼130 (mean 104) minutes, with no perioperative complications. Nine of the cases were successfully repaired in the first surgery and 1 in the second. The patients were discharged after an average of 7 hospital days postoperatively and followed up for 6ï¼90 months without recurrence. CONCLUSIONS: The York-Mason procedure is a reliable and effective option for the treatment of urethrorectal fistula, with the advantages low morbidity, short operation time and fast recovery.
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Fístula Retal , Fístula Urinária , Humanos , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Prostatectomia , Fístula Retal/cirurgia , Fístula Urinária/cirurgiaRESUMO
BACKGROUND: Chronic active Epstein-Barr virus infection (CAEBV) is a rare disease, which is difficult to be differentiated from inflammatory bowel disease (IBD). To cause the attention, we present twelve cases of CAEBV in immunocompetent patients with gastrointestinal tract involvement. METHODS: Twelve patients who fulfilled the diagnostic criteria of CAEBV were enrolled in this retrospective study. The control group was consisted of twenty-four IBD patients with EBV-DNA value increased in peripheral blood. The clinicopathologic and endoscopic characteristics were reviewed and analyzed. RESULTS: The major clinical presentations of CAEBV patients were intermittent fever (100%), hepatomegaly/splenomegaly (58%), lymphadenopathy (50%), diarrhea (50%) and hematochezia (50%). Compared with IBD patients, the incidence of intermittent fever and increased level of ferritin were significantly higher among CAEBV patients. The median values for EBV detected in peripheral blood were significantly higher in CAEBV group (1.42*10^6 copies/µg) than in IBD group (3.2*10^3 copies/µg, p<0.05). The main endoscopic findings of CAEBV included multifocal or isolated, irregular, multiform ulcers and diffuse inflammation, lacking of typical cobblestone appearance. Ten patients died within 5 years of disease onset. The average survival time is 21 months. CONCLUSIONS: Symptoms such as intermittent fever, increased level of ferritin and atypical endoscopic findings could be a sign for CAEBV. Early detections of EBV-DNA in serum and EBV-encoded small nuclear RNA (EBER) by in situ hybridization in intestinal tissue are essential for differential diagnosis between CAEBV and IBD.
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Infecções por Vírus Epstein-Barr , Doenças Inflamatórias Intestinais , Doença Crônica , Infecções por Vírus Epstein-Barr/diagnóstico , Herpesvirus Humano 4/genética , Humanos , Doenças Inflamatórias Intestinais/diagnóstico , Estudos RetrospectivosRESUMO
BACKGROUND: Nutrients involved in one-carbon metabolism may play a key role in pancreatic carcinogenesis. The aim of this study was to examine the association between pancreatic cancer risk and intake or blood levels of vitamins B6, B12 and methionine via meta-analysis. METHODS: A systematic search was performed in PubMed, Web of Knowledge and Chinese National Knowledge Infrastructure (CNKI) up to April 2020 to identify relevant studies. Risk estimates and their 95% confidence intervals (CIs) were retrieved from the studies and combined by a random-effect model. RESULTS: A total of 18 studies were included in this meta-analysis on the association of vitamin B6, B12 and methionine with pancreatic cancer risk. The combined risk estimate (95% CI) of pancreatic cancer for the highest vs lowest category of vitamin B6 intake and blood pyridoxal 5'-phosphate (PLP, active form of vitamin B6) levels was 0.63 (0.48-0.79) and 0.65 (0.52-0.79), respectively. The results indicated a non-linear dose-response relationship between vitamin B6 intake and pancreatic risk. Linear dose-response relationship was found, and the risk of pancreatic cancer decreased by 9% for every 10 nmol/L increment in blood PLP levels. No significant association were found between pancreatic cancer risk and vitamin B12 intake, blood vitamin B12 levels, methionine intake and blood methionine levels. CONCLUSION: Our study suggests that high intake of vitamin B6 and high concentration of blood PLP levels may be protective against the development of pancreatic cancer. Further research are warranted to confirm the results.
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Neoplasias Pancreáticas , Vitamina B 6 , Dieta , Ácido Fólico , Humanos , Metionina , Neoplasias Pancreáticas/epidemiologia , Fatores de Risco , Vitamina B 12RESUMO
In this study, a solid-phase extraction with liquid chromatography and tandem mass spectrometry method was developed to determine the degree of glycosylation of glycosylation sites and the ratio of free carrier protein to total carrier protein for glycoconjugate vaccines. To remove and enrich the glycosylated peptides, a solid-phase extraction method was developed, optimized, and hyphenated to liquid chromatography-tandem mass spectrometry. The developed solid-phase extraction with liquid chromatography-tandem mass spectrometry method was shown to possess a wide linear dynamic range (0.03-100 µg/mL), a high sensitivity (0.03 µg/mL for CRM197), good interday and intra-day precision (relative standard deviation of peak area < 3.3%), and good recoveries from vaccine matrix (90-105%). Finally, the method was utilized to determine the degree of glycosylation and free carrier protein to total carrier protein ratio for pneumococcal conjugate vaccines and meningococcal vaccines. For quality evaluation of glycoconjugate vaccines, the method could provide more information than the traditional size exclusion chromatography method. Fourteen and twelve reported glycosylation sites for CRM197- and tetanus toxin-based vaccines can be detected, respectively.
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Glicoconjugados/análise , Vacinas/análise , Cromatografia Líquida , Glicoconjugados/metabolismo , Glicosilação , Extração em Fase Sólida , Espectrometria de Massas em Tandem , Vacinas/metabolismoRESUMO
Five new diterpenes, including an unprecedented 5,5,6,6,5-pentacyclic diterpene, sponalactone (1), two new spongian diterpenes, 17- O-acetylepispongiatriol (2) and 17- O-acetylspongiatriol (3), and two new spongian diterpene artifacts, 15α,16α-dimethoxy-15,16-dihydroepispongiatriol (4) and 15α-ethoxyepispongiatriol-16(15 H)-one (5), were isolated from a South China Sea collection of the marine sponge Spongia officinalis, together with three known analogues (6-8). The structures of the new diterpenes were elucidated by extensive spectroscopic analysis. The absolute configurations were established on the basis of ECD data. Compounds 1-5 and 7 exhibited moderate inhibition against LPS-induced NO production in RAW264.7 macrophages with IC50 values of 12-32 µM.
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Diterpenos/farmacologia , Macrófagos/efeitos dos fármacos , Poríferos/química , Animais , China , Diterpenos/química , Diterpenos/isolamento & purificação , Espectroscopia de Ressonância Magnética , Estrutura MolecularRESUMO
Four new steroids, named 7-dehydroerectasteroid F (1), 11α-acetoxyarmatinol A (2), 22,23-didehydroarmatinol A (3), and 3-O-acetylhyrtiosterol (4), together with 11 previously described analogues, were isolated from a South China Sea collection of the soft coral Dendronephthya gigantea. The structures of the new steroids were elucidated by comprehensive spectroscopic analysis and by comparison with previously reported data. Compound 1 showed potent protection against H2O2-induced oxidative damage in neuron-like PC12 cells by promoting nuclear translocation of Nrf2 and enhancing the expression of HO-1. 1 represents the first steroid-type antioxidant from marine organisms.