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1.
RSC Adv ; 14(21): 15167-15177, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38741618

RESUMEN

Significant advancements have been made in catalytic asymmetric α-C-H bond functionalization of ethers via carbenoid insertion over the past decade. Effective asymmetric catalytic systems, featuring a range of chiral metal catalysts, have been established for the enantioselective synthesis of diverse ether substrates. This has led to the generation of various enantioenriched, highly functionalized oxygen-containing structural motifs, facilitating their application in the asymmetric synthesis of bioactive natural products.

2.
Cancer Sci ; 115(5): 1476-1491, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38475938

RESUMEN

Liver cancer is the sixth most common cancer and the third leading cause of cancer-related death globally. Despite efforts being made in last two decades in cancer diagnosis and treatment, the 5-year survival rate of liver cancer remains extremely low. TRIM21 participates in cancer metabolism, glycolysis, immunity, chemosensitivity and metastasis by targeting various substrates for ubiquitination. TRIM21 serves as a prognosis marker for human hepatocellular carcinoma (HCC), but the mechanism by which TRIM21 regulates HCC tumorigenesis and progression remains elusive. In this study, we demonstrated that TRIM21 protein levels were elevated in human HCC. Elevated TRIM21 expression was associated with HCC progression and poor survival. Knockdown of TRIM21 in HCC cell lines significantly impaired cell growth and metastasis and enhanced sorafenib-induced toxicity. Mechanistically, we found that knockdown of TRIM21 resulted in cytosolic translocation and inactivation of YAP. At the molecular level, we further identified that TRIM21 interacted and induced ubiquitination of MST1, which resulted in MST1 degradation and YAP activation. Knockdown of MST1 or overexpression of YAP reversed TRIM21 knockdown-induced impairment of HCC growth and chemosensitivity. Taken together, the current study demonstrates a novel mechanism that regulates the Hippo pathway and reveals TRM21 as a critical factor that promotes growth and chemoresistance in human HCC.


Asunto(s)
Carcinoma Hepatocelular , Proliferación Celular , Neoplasias Hepáticas , Ribonucleoproteínas , Transducción de Señal , Factores de Transcripción , Ubiquitinación , Proteínas Señalizadoras YAP , Humanos , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/genética , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Línea Celular Tumoral , Proteínas Señalizadoras YAP/metabolismo , Proteínas Señalizadoras YAP/genética , Ribonucleoproteínas/metabolismo , Ribonucleoproteínas/genética , Sorafenib/farmacología , Sorafenib/uso terapéutico , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Ratones , Animales , Regulación Neoplásica de la Expresión Génica , Masculino , Fosfoproteínas/metabolismo , Fosfoproteínas/genética , Técnicas de Silenciamiento del Gen , Femenino , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas/genética
3.
Trials ; 25(1): 137, 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38383461

RESUMEN

BACKGROUND: The advantages of laparoscopic left-sided hepatectomy (LLH) for treating hepatolithiasis in terms of the time to postoperative length of hospital stay (LOS), morbidity, long-term abdominal wall hernias, hospital costs, residual stone rate, and recurrence of calculus have not been confirmed by a randomized controlled trial. The aim of this trial is to compare the safety and effectiveness of LLH with open left-sided hepatectomy (OLH) for the treatment of hepatolithiasis. METHODS: Patients with hepatolithiasis eligible for left-sided hepatectomy will be recruited. The experimental design will produce two randomized arms (laparoscopic and open hepatectomy) at a 1:1 ratio and a prospective registry. All patients will undergo surgery in the setting of an enhanced recovery after surgery (ERAS) programme. The prospective registry will be based on patients who cannot be randomized because of the explicit treatment preference of the patient or surgeon or because of ineligibility (not meeting the inclusion and exclusion criteria) for randomization in this trial. The primary outcome is the LOS. The secondary outcomes are percentage readmission, morbidity, mortality, hospital costs, long-term incidence of incisional hernias, residual stone rate, and recurrence of calculus. It will be assumed that, in patients undergoing LLH, the length of hospital stay will be reduced by 1 day. A sample size of 86 patients in each randomization arm has been calculated as sufficient to detect a 1-day reduction in LOS [90% power and α = 0.05 (two-tailed)]. The trial is a randomized controlled trial that will provide evidence for the merits of laparoscopic surgery in patients undergoing liver resection within an ERAS programme. CONCLUSIONS: Although the outcomes of LLH have been proven to be comparable to those of OLH in retrospective studies, the use of LLH remains restricted, partly due to the lack of short- and long-term informative RCTs pertaining to patients with hepatolithiasis in ERAS programmes. To evaluate the surgical and long-term outcomes of LLH, we will perform a prospective RCT to compare LLH with OLH for hepatolithiasis within an ERAS programme. TRIAL REGISTRATION: ClinicalTrials.gov NCT03958825. Registered on 21 May 2019.


Asunto(s)
Cálculos , Laparoscopía , Litiasis , Hepatopatías , Humanos , Hepatectomía/efectos adversos , Hepatectomía/métodos , Hepatopatías/diagnóstico , Hepatopatías/cirugía , Litiasis/cirugía , Estudios Retrospectivos , Resultado del Tratamiento , Laparoscopía/efectos adversos , Laparoscopía/métodos , Tiempo de Internación , Complicaciones Posoperatorias/epidemiología , Ensayos Clínicos Controlados Aleatorios como Asunto
4.
Gene ; 908: 148304, 2024 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-38387708

RESUMEN

Hereditary cancer syndromes result from the presence of inherited pathogenic variants within susceptibility genes. However, the susceptibility genes associated with hereditary cancer syndrome remain predominantly unidentified. Here, we reported a case of hereditary cancer syndrome observed in a Chinese family harboring a germline mutation in Tensin1 (TNS1). We described a 59-year-old female patient presented with Multiple myeloma and Thyroid carcinoma. The proband and her family members exhibited suspected tumor syndrome due to occurrences of other cancer cases. After oncogenetic counseling, whole-exome sequencing and Sanger sequencing were conducted and a primary driver mutation of TNS1 (NM_022648.7:c.2999-1G > C) was detected. Gene Expression Profiling Interactive Analysis revealed that TNS1 was expressed lower in different tumors when compared to normal, including Pancreatic adenocarcinoma, Breast invasive carcinoma, Thyroid carcinoma andColon adenocarcinoma cells. Despite the well-established role of TNS1 as a tumor suppressor in breast cancer and colorectal cancer, its potential utility as a marker gene for diagnosis and treatment of pancreatic cancer remains uncertain. Here, our data demonstrated that knockdown of TNS1 could promote cell proliferation and migration in Pancreatic adenocarcinoma (PDAC) cells. In addition, TNS1 regulated migration through EMT signaling pathway in PDAC cells. Our findings proposed that this variant was likely involved in cancer predisposition by disrupting the normal splicing process. In summary, we presented a genetic disease by linking an intronic mutation inTNS1. We aim to provide early detection of cancers by identifying germline variants in susceptibility genes.


Asunto(s)
Adenocarcinoma , Síndromes Neoplásicos Hereditarios , Neoplasias Pancreáticas , Humanos , Femenino , Persona de Mediana Edad , Mutación de Línea Germinal , Neoplasias Pancreáticas/genética , Adenocarcinoma/genética , Predisposición Genética a la Enfermedad , Síndromes Neoplásicos Hereditarios/genética , Células Germinativas , Tensinas/genética
5.
Influenza Other Respir Viruses ; 18(1): e13246, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38188372

RESUMEN

Background: In 2019, the Louisiana Department of Health reported an early influenza B/Victoria (B/VIC) virus outbreak. Method: As it was an atypically large outbreak, we deployed to Louisiana to investigate it using genomics and a triplex real-time RT-PCR assay to detect three antigenically distinct B/VIC lineage variant viruses. Results: The investigation indicated that B/VIC V1A.3 subclade, containing a three amino acid deletion in the hemagglutinin and known to be antigenically distinct to the B/Colorado/06/2017 vaccine virus, was the most prevalent circulating virus within the specimens evaluated (86/88 in real-time RT-PCR). Conclusion: This work underscores the value of portable platforms for rapid, onsite pathogen characterization.


Asunto(s)
Vacunas contra la Influenza , Gripe Humana , Humanos , Gripe Humana/epidemiología , Brotes de Enfermedades , Louisiana/epidemiología
6.
Lasers Med Sci ; 39(1): 16, 2023 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-38141129

RESUMEN

Pulsed dye laser (PDL) is the most commonly used method for port-wine stain (PWS); however, no studies have reported the safety of PDL. This review aimed to collect and summarize complications reported in relevant literature, assess complication rates in treating PWS with PDL, and explore the relevant influencing factors. A systematic review and meta-analysis were conducted to search for related studies in PubMed, Embase, and the Cochrane Library until August 2022. Two reviewers independently evaluated the risk of bias of included studies. Stata Software version 17.0 was used for the analysis. All complications reported in the literature are divided into acute phase complications and long-term complications. Overall pooled purpura, edema, crusting, blistering, hyperpigmentation, hypopigmentation, and scarring rates were 98.3%, 97.6%, 21.5%, 8.7%, 12.8%, 0.9%, and 0.2%, respectively. Although the acute adverse reactions were found to be common, the long-term permanent complications clearly have a lower frequency, and the occurrence of scarring is much lower than that initially thought. This indicates that effective protective measures after treatment are very important for preventing scar formation. Overall, PDL treatment for PWS shows a high level of safety and low chances of causing long-term complications.


Asunto(s)
Láseres de Colorantes , Mancha Vino de Oporto , Humanos , Mancha Vino de Oporto/radioterapia , Mancha Vino de Oporto/cirugía , Resultado del Tratamiento , Láseres de Colorantes/efectos adversos , Cicatriz , Terapia Combinada
7.
Bladder (San Franc) ; 10: e21200006, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37936585

RESUMEN

OBJECTIVE: To investigate the utility of fluorescence in situ hybridization (FISH) in secondary electroresection of bladder cancer. METHODS: From January 2016 to April 2022, bladder cancer patients who had undergone secondary electroresection in Tongji Hospital and had preoperative urine FISH were recruited, and the positive rate, accuracy, sensitivity, specificity, genetic material changes and predictive power on malignancy degree of FISH in the secondary electroresection of bladder cancer were examined. RESULTS: Twenty-six patients with bladder cancer were included in this study, and 8 were confirmed by secondary electroresection, including 6 cases positive for FISH positive and 2 negative for FISH. Besides, among the subjects, 18 were without tumor recurrence, including 1 case with positive FISH results and 17 with negative FISH results. Tumor recurrence was diagnosed in 85.71% (6/7) of FISH-positive patients in secondary electroresection while only 10.53% (2/19) of FISH-negative patients were found to develop tumor recurrence in the secondary electroresection. The sensitivity of FISH for the detection of bladder cancer before secondary electroresection was 75%, with a specificity of 94.44%, and an accuracy of 88.46%. A 6-month follow-up revealed that 2 of the 8 recurrent patients underwent radical resection of bladder cancer, and the remaining 6 patients had no recurrence, as confirmed by regular bladder perfusion and microscopy. In the 18 non-recurrent patients during secondary electroresection, no recurrence developed. CONCLUSIONS: Urine FISH can achieve a high detection rate and specificity for secondary electroresection of bladder cancer. If a bladder cancer patient who are indicated for secondary electroresection is negative for urine FISH, the recurrence rate after secondary electroresection will be low, and the cystoscopy can be performed before deciding whether to perform secondary electroresection.

8.
Environ Sci Pollut Res Int ; 30(49): 108288-108300, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37743446

RESUMEN

The production of waste printed circuit boards (WPCBs) is increasing, and its complex composition makes recycling difficult. In addition, the presence of heavy metals and brominated flame retardants makes it a hazardous waste. Therefore, its recycling is a necessary way for resource recycling and green sustainable development. The purpose of this study is to propose a green, efficient, and pollution-free recycling process as an alternative to recycle WPCBs. In this work, an alkaline metal oxide catalytic pyrolysis process was used to recover WPCBs. In the presence of alkali metal oxides (such as Ca(OH)2) and coexisting copper, Ca(OH)2 and coexisting copper are transformed into CaBr2 and Cu Br by reacting with organic bromine in WPCBs and remaining in the solid phase product. The bromine content and the proportion of inorganic bromine in the solid phase products were 87.68% and 87.56%, respectively. In addition, the content of organic bromine in the pyrolysis oil obtained by co-pyrolysis was significantly reduced. This study demonstrated the feasibility of Ca(OH)2 catalytic pyrolysis for WPCB recovery.


Asunto(s)
Residuos Electrónicos , Metales Pesados , Cobre , Bromo , Pirólisis , Residuos Electrónicos/análisis , Reciclaje
9.
Huan Jing Ke Xue ; 44(8): 4575-4584, 2023 Aug 08.
Artículo en Chino | MEDLINE | ID: mdl-37694651

RESUMEN

The objective of this study was to explore the microecological variability in farmland soil fertility in response to millet-peanut intercropping patterns by clarifying the effects of millet-peanut 4:4 intercropping on soil bacterial community structure and its diversity, as well as to provide a reference basis for promoting ecological restoration and arable land quality improvement in the lower Yellow River farmland. The Illumina MiSeq high-throughput sequencing technology and QIIME 2 platform were used to analyze the differences in bacterial community composition and their influencing factors in five soils[sole millet (SM), sole peanut (SP), intercropping millet (IM), intercropping peanut (IP), and millet-peanut intercropping (MP)] and to predict their ecological functions. The results showed that the α-diversity of intercropping soil bacterial communities differed from that of monocropping, though not significantly, whereas the ß-diversity was significantly different (P<0.05). A total of 7081 ASVs were obtained from all soil samples, classified into 34 phyla, 109 orders, 256 class, 396 families, 710 genera, and 1409 species, of which 727 ASVs were shared, accounting for 24.5% to 27.8% in five soil species. The bacterial communities of millet-peanut intercropping and its monocropping soils were similar in phylum composition but varied in relative abundance. All five soils were dominated by the Actinobacteria, Proteobacteria, Acidobacteria, and Chloroflexi, with a relative abundance of 79.40%-81.33%. Soil organic carbon and alkaline nitrogen were the most important factors causing differences in the structures of the five soil bacterial communities at the phylum and genus levels, respectively. The PICRUSt functional prediction revealed that the relative abundance of primary functional metabolism was the largest (78.9%-79.3%), and the relative abundance of secondary functional exogenous biodegradation and metabolism fluctuated the most (CV=3.782%). In terms of the BugBase phenotype, the relative abundance of oxidative stress-tolerant bacteria increased in intercropping millet or peanut soils compared to that in the corresponding monocultures and significantly increased in intercropping millet soils compared to that in sole millet (P<0.05). Oxidative stress-tolerant, Gram-positive, and aerobic phenotypes were highly significantly positively correlated with each other (P<0.01), and all three showed highly significant negative correlations with potential pathogenicity and Gram-negative and anaerobic phenotypes (P<0.01). This showed that millet-peanut intercropping resulted in differences in soil bacterial community diversity, abundance, and metabolic functions and the possibility of reducing the occurrence of potential soil diseases. It can be used to regulate the soil microbiological environment to promote ecological restoration and sustainable development of farmland in the lower Yellow River.


Asunto(s)
Arachis , Mijos , Humanos , Carbono , Granjas , Ríos , Suelo
10.
Sci Rep ; 13(1): 15244, 2023 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-37709823

RESUMEN

We aim to develop a nomogram to predict overt hepatic encephalopathy (OHE) after transjugular intrahepatic portosystemic shunt (TIPS) in patients with portal hypertension, according to demographic/clinical indicators such as age, creatinine, blood ammonia, indocyanine green retention rate at 15 min (ICG-R15) and percentage of Portal pressure gradient (PPG) decline. In this retrospective study, 296 patients with portal hypertension who received elective TIPS in Beijing Shijitan Hospital from June 2018 to June 2020 were included. These patients were randomly divided into a training cohort (n = 207) and a validation cohort (n = 89). According to the occurrence of OHE, patients were assigned to OHE group and non-OHE group. Both univariate and multivariate analyses were performed to determine independent variables for predicting OHE after TIPS. Accordingly, receiver operating characteristic (ROC) curve, calibration curve, and decision curve analysis (DCA) were used to compare the accuracy and superiority of a novel model with conventional Child-Pugh and MELD scoring model. Age (OR 1.036, 95% CI 1.002-1.070, p = 0.037), Creatinine (OR 1.011, 95% CI 1.003-1.019, p = 0.009), Blood ammonia (OR 1.025, 95% CI 1.006-1.044, p = 0.011), ICG-R15 (OR 1.030, 95% CI 1.009-1.052, p = 0.004) and Percentage decline in PPG (OR 1.068, 95% CI 1.029-1.109, p = 0.001) were independent risk factors for OHE after TIPS using multifactorial analysis. A nomogram was constructed using a well-fit calibration curve for each of these five covariates. When compared to Child-Pugh and MELD score, this new nomogram has a better predictive value (C-index = 0.828, 95% CI 0.761-0.896). Consistently, this finding was reproduceable in validation cohort and confirmed with DCA. A unique nomogram was developed to predict OHE after TIPS in patients with PHT, with a high prediction sensitivity and specificity performance than commonly applied scoring systems.


Asunto(s)
Encefalopatía Hepática , Hipertensión Portal , Derivación Portosistémica Intrahepática Transyugular , Humanos , Encefalopatía Hepática/etiología , Amoníaco , Creatinina , Nomogramas , Derivación Portosistémica Intrahepática Transyugular/efectos adversos , Estudios Retrospectivos , Hipertensión Portal/etiología , Hipertensión Portal/cirugía , Verde de Indocianina
11.
Int J Urol ; 30(12): 1122-1132, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37602677

RESUMEN

OBJECTIVES: This study aims to reveal immunophenotypes associated with immunotherapy response in bladder cancer, identify the signature genes of immune subtypes, and provide new molecular targets for improving immunotherapy response. METHODS: Bladder cancer immunophenotypes were characterized in the bulk RNA sequencing dataset GSE32894 and Imvigor210, and gene expression signatures were established to identify the immunophenotypes. Expression of gene signatures were validated in single-cell RNA sequencing dataset GSE145140 and human proteins expression data source. Investigation of Immunotherapy Response was performed in IMvigor210 dataset. Prognosis of tumor immunophenotypes was further analyzed. RESULTS: Inflamed and immune-excluded immunophenotypes were characterized based on the tumor immune cell scores. Risk score models that were established rely on RNA sequencing profiles and overall survival of bladder cancer cohorts. The inflamed tumors had lower risk scores, and the low-risk tumors were more likely to respond to atezolizumab, receiving complete response/partial response (CR/PR). Patients who responded to atezolizumab had higher SRRM4 and lower NPHS1 and TMEM72 expression than the non-responders. SRRM4 expression was a protective factor for bladder cancer prognosis, while the NPHS1 and TMEM72 showed the opposite pattern. CONCLUSION: This study provided a novel classification method for tumor immunophenotypes. Bladder cancer immunophenotypes can predict the response to immune checkpoint blockade. The immunophenotypes can be identified by the expression of signature genes.


Asunto(s)
Síndrome Nefrótico , Neoplasias de la Vejiga Urinaria , Humanos , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Neoplasias de la Vejiga Urinaria/genética , Vejiga Urinaria , Inmunoterapia , Microambiente Tumoral , Pronóstico , Proteínas del Tejido Nervioso
12.
Virus Genes ; 59(4): 554-561, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37184730

RESUMEN

In October 2020, an avian paramyxovirus serotype 14 (APMV-14)-designated chicken/Fujian/2160/2020 (FJ2160) was isolated from tracheal and cloacal swab sample of chicken collected from live bird market in Fujian province in China during the active surveillance program. The complete genome of FJ2160 comprised 15,444 nucleotides (nt) complying with the paramyxovirus "rule of six" and encoded six non-overlapping structural proteins in the order of 3'-NP-P-M-F-HN-L-'5. The complete genome sequence analysis showed that FJ2160 had the highest identity (90.0%) with the APMV-14 isolated from Japan, while the nucleotide sequence identities of FJ2160 and other APMVs ranged from 42.4 to 51.1%. The F protein cleavage site was TREGR↓L, which resembled a lentogenic strain of APMV-1. Phylogenetic analysis revealed that the FJ2160 closest relative was APMV-14. The intracerebral pathogenicity index (ICPI) tests indicated that the virus was lentogenic. This is the first report of APMV-14 in China. These results provide evidence that APMV-14 could infect chickens and reveal the genetic characteristics and biological properties of the virus, which can help to better understand this new emerging APMV-14.


Asunto(s)
Avulavirus , Pollos , Animales , Serogrupo , Genoma Viral/genética , Avulavirus/genética , Filogenia , China
13.
Front Immunol ; 14: 1151109, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37063862

RESUMEN

Introduction: It is believed that ovarian cancer (OC) is the most deadly form of gynecological cancer despite its infrequent occurrence, which makes it one of the most salient public health concerns. Clinical and preclinical studies have revealed that intratumoral CD4+ T cells possess cytotoxic capabilities and were capable of directly killing cancer cells. This study aimed to identify the CD4+ conventional T cells-related genes (CD4TGs) with respect to the prognosis in OC. Methods: We obtained the transcriptome and clinical data from the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. CD4TGs were first identified from single-cell datasets, then univariate Cox regression was used to screen prognosis-related genes, LASSO was conducted to remove genes with coefficient zero, and multivariate Cox regression was used to calculate riskscore and to construct the CD4TGs risk signature. Kaplan-Meier analysis, univariate Cox regression, multivariate Cox regression, time-dependent receiver operating characteristics (ROC), decision curve analysis (DCA), nomogram, and calibration were made to verify and evaluate the risk signature. Gene set enrichment analyses (GSEA) in risk groups were conducted to explore the tightly correlated pathways with the risk group. The role of riskscore has been further explored in the tumor microenvironment (TME), immunotherapy, and chemotherapy. A risk signature with 11 CD4TGs in OC was finally established in the TCGA database and furtherly validated in several GEO cohorts. Results: High riskscore was significantly associated with a poorer prognosis and proven to be an independent prognostic biomarker by multivariate Cox regression. The 1-, 3-, and 5-year ROC values, DCA curve, nomogram, and calibration results confirmed the excellent prediction power of this model. Compared with the reported risk models, our model showed better performance. The patients were grouped into high-risk and low-risk subgroups according to the riskscore by the median value. The low-risk group patients tended to exhibit a higher immune infiltration, immune-related gene expression and were more sensitive to immunotherapy and chemotherapy. Discussion: Collectively, our findings of the prognostic value of CD4TGs in prognosis and immune response, provided valuable insights into the molecular mechanisms and clinical management of OC.


Asunto(s)
Neoplasias Ováricas , Humanos , Femenino , Pronóstico , Neoplasias Ováricas/genética , Nomogramas , Linfocitos T CD4-Positivos , Calibración , Microambiente Tumoral/genética
14.
J Phys Chem A ; 127(10): 2351-2366, 2023 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-36877868

RESUMEN

Ammonia (NH3) is a promising fuel, because it is carbon-free and easier to store and transport than hydrogen (H2). However, an ignition enhancer such as H2 might be needed for technical applications, because of the rather poor ignition properties of NH3. The combustion of pure NH3 and H2 has been explored widely. However, for mixtures of both gases, mostly only global parameters such as ignition delay times or flame speeds were reported. Studies with extensive experimental species profiles are scarce. Therefore, we experimentally investigated the interactions in the oxidation of different NH3/H2 mixtures in the temperature range of 750-1173 K at 0.97 bar in a plug-flow reactor (PFR), as well as in the temperature range of 1615-2358 K with an average pressure of 3.16 bar in a shock tube. In the PFR, temperature-dependent mole fraction profiles of the main species were obtained via electron ionization molecular-beam mass spectrometry (EI-MBMS). Additionally, for the first time, tunable diode laser absorption spectroscopy (TDLAS) with a scanned-wavelength method was adapted to the PFR for the quantification of nitric oxide (NO). In the shock tube, time-resolved NO profiles were also measured by TDLAS using a fixed-wavelength approach. The experimental results both in PFR and shock tube reveal the reactivity enhancement by H2 on ammonia oxidation. The extensive sets of results were compared with predictions by four NH3-related reaction mechanisms. None of the mechanisms can well predict all experimental results, but the Stagni et al. [React. Chem. Eng. 2020, 5, 696-711] and Zhu et al. [Combust. Flame 2022, 246, 115389] mechanisms perform best for the PFR and shock tube conditions, respectively. Exploratory kinetic analysis was conducted to identify the effect of H2 addition on ammonia oxidation and NO formation, as well as sensitive reactions in different temperature regimes. The results presented in this study can provide valuable information for further model development and highlight relevant properties of H2-assisted NH3 combustion.

15.
Int Urol Nephrol ; 55(10): 2599-2610, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36935438

RESUMEN

PURPOSE: To investigate the effect of grape seed-derived proanthocyanidin B2 (GSPB2) pretreatment on acute renal ischemia-reperfusion injury model of mice. METHODS: 50 mice were divided into 5 groups: Sham group: mice were treated with right nephrectomy. GSPB2 group: GSPB2 was injected intraperitoneally 45 min before right nephrectomy. IRI group: right kidney was resected and the left renal arteriovenous vessel was blocked for 45 min. GSPB2 + IRI group: GSPB2 was intraperitoneally injected 45 min before IRI established. GSPB2 + BRU + IRI group: GSPB2 and brusatol (BRU) were injected intraperitoneally 45 min before IRI established. Creatinine and urea nitrogen of mice were detected, and the kidney morphology and pathological changes of each group were detected by HE staining, PAS staining and transmission electron microscopy. Expressions of Nrf2, HO-1, GRP78, CHOP, and cleaved-caspase3 were detected by immunofluorescence staining and western blotting. RESULTS: Morphology and mitochondrial damages of kidney in GSPB2 + IRI group were significantly alleviated than those in IRI group. Expression levels of Nrf2 and HO-1 were significantly higher in GSPB2 + IRI group than those in IRI group. Expression levels of GRP78, CHOP and cleaved-caspase3 were significantly lower in GSPB2 + IRI group than those in IRI group. However, compared to GSPB2 + IRI group, protective effects of GSPB2 pretreatment were weakened in GSPB2 + BRU + IRI group. CONCLUSIONS: GSPB2 pretreatment could alleviate oxidative stress damage and reduce apoptosis of renal tubular epithelial cells, which might be related to activating the antioxidant system, up-regulating the expression of Nrf2 and HO-1, inhibiting the expressions of GRP78, CHOP and cleaved-caspase3. However, the protective effect could be reversed by brusatol.


Asunto(s)
Proantocianidinas , Daño por Reperfusión , Vitis , Ratones , Animales , Proantocianidinas/farmacología , Proantocianidinas/metabolismo , Vitis/metabolismo , Chaperón BiP del Retículo Endoplásmico , Factor 2 Relacionado con NF-E2/metabolismo , Riñón/patología , Estrés Oxidativo , Apoptosis , Células Epiteliales/metabolismo , Daño por Reperfusión/metabolismo , Estrés del Retículo Endoplásmico
17.
J Phys Chem A ; 127(8): 1923-1940, 2023 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-36800895

RESUMEN

The low reactivity of ammonia (NH3) is the main barrier to applying neat NH3 as fuel in technical applications, such as internal combustion engines and gas turbines. Introducing combustion promoters as additives in NH3-based fuel can be a feasible solution. In this work, the oxidation of ammonia by adding different reactivity promoters, i.e., hydrogen (H2), methane (CH4), and methanol (CH3OH), was investigated in a jet-stirred reactor (JSR) at temperatures between 700 and 1200 K and at a pressure of 1 bar. The effect of ozone (O3) was also studied, starting from an extremely low temperature (450 K). Species mole fraction profiles as a function of the temperature were measured by molecular-beam mass spectrometry (MBMS). With the help of the promoters, NH3 consumption can be triggered at lower temperatures than in the neat NH3 case. CH3OH has the most prominent effect on enhancing the reactivity, followed by H2 and CH4. Furthermore, two-stage NH3 consumption was observed in NH3/CH3OH blends, whereas no such phenomenon was found by adding H2 or CH4. The mechanism constructed in this work can reasonably reproduce the promoting effect of the additives on NH3 oxidation. The cyanide chemistry is validated by the measurement of HCN and HNCO. The reaction CH2O + NH2 ⇄ HCO + NH3 is responsible for the underestimation of CH2O in NH3/CH4 fuel blends. The discrepancies observed in the modeling of NH3 fuel blends are mainly due to the deviations in the neat NH3 case. The total rate coefficient and the branching ratio of NH2 + HO2 are still controversial. The high branching fraction of the chain-propagating channel NH2 + HO2 ⇄ H2NO + OH improves the model performance under low-pressure JSR conditions for neat NH3 but overestimates the reactivity for NH3 fuel blends. Based on this mechanism, the reaction pathway and rate of production analyses were conducted. The HONO-related reaction routine was found to be activated uniquely by adding CH3OH, which enhances the reactivity most significantly. It was observed from the experiment that adding ozone to the oxidant can effectively initiate NH3 consumption at temperatures below 450 K but unexpectedly inhibit the NH3 consumption at temperatures higher than 900 K. The preliminary mechanism reveals that adding the elementary reactions between NH3-related species and O3 is effective for improving the model performance, but their rate coefficients have to be refined.

18.
BMC Public Health ; 23(1): 64, 2023 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-36627582

RESUMEN

BACKGROUND: People living with HIV(PLWH) are deemed more vulnerable to the SARS-CoV-2 infection than the uninfected population. Vaccination is an effective measure for COVID-19 control, yet, little knowledge exists about the willingness of men who have sex with men (MSM) living with HIV in China to be vaccinated. METHODS: This cross-sectional study evaluated the willingness of MSM living with HIV to receive COVID-19 vaccination in six cities of Guangdong, China, from July to September 2020. Factors associated with willingness to receive COVID-19 vaccination using multivariable logistic regression. RESULTS: In total, we recruited 944 HIV-positive MSM with a mean age of 29.2 ± 7.7 years. Of all participants, 92.4% of them were willing to receive the COVID-19 vaccine. Participants who were separated, divorced, or widowed (adjusted OR: 5.29, 95%CI: 1.02-27.48), had an annual income higher than 9,000 USD (adjusted OR: 1.70, 95%CI: 1.01-2.86), had ever taken an HIV self-test (adjusted OR: 1.78, 95%CI: 1.07-2.95), had ever disclosed sexual orientation to a doctor/nurse (adjusted OR: 3.16, 95%CI: 1.33-7.50), had ever disclosed sexual orientation to others besides their male partners (adjusted OR: 2.18, 95%CI: 1.29-3.69) were more willing to receive the vaccine. Sex with a female partner in the past six months decreased the likelihood of willingness to receive the vaccine (adjusted OR: 0.40, 95%CI: 0.17-0.95). Economic burden, worry that my health condition could not bear the risk of receiving COVID-19 vaccines, and concern that the vaccination would affect the immune status and antiretroviral therapy were the main reasons for unwillingness to receive vaccination. CONCLUSION: Our study showed that HIV-positive MSM had a high willingness to receive the COVID-19 vaccination. Targeted interventions such as health education should be conducted among MSM with HIV infection to enhance COVID-19 vaccine uptake.


Asunto(s)
COVID-19 , Infecciones por VIH , Minorías Sexuales y de Género , Masculino , Humanos , Femenino , Adulto Joven , Adulto , Homosexualidad Masculina , Vacunas contra la COVID-19/uso terapéutico , Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , Estudios Transversales , COVID-19/epidemiología , COVID-19/prevención & control , Aceptación de la Atención de Salud , Encuestas y Cuestionarios , SARS-CoV-2 , Vacunación , China/epidemiología
19.
PLoS Pathog ; 19(1): e1010814, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36626401

RESUMEN

We currently have an incomplete understanding of why only a fraction of human antibodies that bind to flaviviruses block infection of cells. Here we define the footprint of a strongly neutralizing human monoclonal antibody (mAb G9E) with Zika virus (ZIKV) by both X-ray crystallography and cryo-electron microscopy. Flavivirus envelope (E) glycoproteins are present as homodimers on the virion surface, and G9E bound to a quaternary structure epitope spanning both E protomers forming a homodimer. As G9E mainly neutralized ZIKV by blocking a step after viral attachment to cells, we tested if the neutralization mechanism of G9E was dependent on the mAb cross-linking E molecules and blocking low-pH triggered conformational changes required for viral membrane fusion. We introduced targeted mutations to the G9E paratope to create recombinant antibodies that bound to the ZIKV envelope without cross-linking E protomers. The G9E paratope mutants that bound to a restricted epitope on one protomer poorly neutralized ZIKV compared to the wild-type mAb, demonstrating that the neutralization mechanism depended on the ability of G9E to cross-link E proteins. In cell-free low pH triggered viral fusion assay, both wild-type G9E, and epitope restricted paratope mutant G9E bound to ZIKV but only the wild-type G9E blocked fusion. We propose that, beyond antibody binding strength, the ability of human antibodies to cross-link E-proteins is a critical determinant of flavivirus neutralization potency.


Asunto(s)
Infección por el Virus Zika , Virus Zika , Humanos , Virus Zika/genética , Epítopos , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Subunidades de Proteína , Microscopía por Crioelectrón , Proteínas del Envoltorio Viral/genética , Anticuerpos Monoclonales
20.
Fa Yi Xue Za Zhi ; 39(6): 549-556, 2023 Dec 25.
Artículo en Inglés, Chino | MEDLINE | ID: mdl-38228473

RESUMEN

OBJECTIVES: To study the changes of protein levels in peripheral blood after it dried. METHODS: The proteins from whole blood and bloodstains were detected by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and normalized by the label-free quantification (LFQ) method. The differential proteins were analyzed by using R 4.2.1 software, limma and edgeR package. The analysis of biological function, signaling pathway and subcellular localization for the differential proteins was then performed. RESULTS: A total of 623 and 596 proteins were detected in whole blood and bloodstains, respectively, of which 31 were statistically significant in the quantitative results, including 10 up-regulated and 21 down-regulated proteins in bloodstains. CONCLUSIONS: The protein abundances in whole blood and bloodstains are highly correlated, and the variation of protein abundances may be related to the changes of endogenous and structural proteins in cells. The application of proteomics technology can assist the screening and identification of protein biomarkers, thereby introducing new biomarkers for forensic research.


Asunto(s)
Manchas de Sangre , Espectrometría de Masas en Tándem , Cromatografía Liquida/métodos , Espectrometría de Masas en Tándem/métodos , Proteómica/métodos , Biomarcadores
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