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1.
Small ; 20(1): e2304776, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37658502

RESUMEN

Efficient artificial photosynthesis of disulfide bonds holds promises to facilitate reverse decoding of genetic codes and deciphering the secrets of protein multilevel folding, as well as the development of life science and advanced functional materials. However, the incumbent synthesis strategies encounter separation challenges arising from leaving groups in the ─S─S─ coupling reaction. In this study, according to the reaction mechanism of free-radical-triggered ─S─S─ coupling, light-driven heterojunction functional photocatalysts are tailored and constructed, enabling them to efficiently generate free radicals and trigger the coupling reaction. Specifically, perovskites and covalent organic frameworks (COFs) are screened out as target materials due to their superior light-harvesting and photoelectronic properties, as well as flexible and tunable band structure. The in situ assembled Z-scheme heterojunction MAPB-M-COF (MAPbBr3 = MAPB, MA+ = CH3 NH2 + ) demonstrates a perfect trade-off between quantum efficiency and redox chemical potential via band engineering management. The MAPB-M-COF achieves a 100% ─S─S─ coupling yield with a record photoquantum efficiency of 11.50% and outstanding cycling stability, rivaling all the incumbent similar reaction systems. It highlights the effectiveness and superiority of application-oriented band engineering management in designing efficient multifunctional photocatalysts. This study demonstrates a concept-to-proof research methodology for the development of various integrated heterojunction semiconductors for light-driven chemical reaction and energy conversion.

2.
Small ; : e2402459, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38751061

RESUMEN

The electrocatalytic conversion of inert CO2 to value-added chemical fuels powered by renewable energy is one of the benchmark approaches to address excessive carbon emissions and achieve carbon-neutral energy restructuring. However, the adsorption/activation of supersymmetric CO2 is facing insurmountable challenges that constrain its industrial-scale applications. Here, this theory-guided study confronts these challenges by leveraging the synergies of bimetallic sites and defect engineering, where pyrochlore-type semiconductor A2B2O7 is employed as research platform and the conversion of CO2-to-HCOOH as the model reaction. Specifically, defect engineering intensified greatly the chemisorption-induced CO2 polarization via the bimetallic coordination, thermodynamically beneficial to the HCOOH production via the *HCO2 intermediate. The optimal V-BSO-430 electrocatalyst with abundant surface oxygen vacancies achieved a superior HCOOH yield of 116.7 mmol h-1 cm-2 at -1.2 VRHE, rivalling the incumbent similar reaction systems. Furthermore, the unique catalytic unit featured with a Bi1-Sn-Bi2 triangular structure, which is reconstructed by defect engineering, and altered the pathway of CO2 adsorption and activation to allow the preferential affinity of the suspended O atom in *HCO2 to H. As a result, V-BSO-430 gave an impressive FEHCOOH of 93% at -1.0 VRHE. This study held promises for inspiring the exploration of bimetallic materials from the massive semiconductor database.

3.
Langmuir ; 40(17): 9020-9027, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38632903

RESUMEN

We prepared BiOCl, BiO(ClBr), BiO(ClBrI), and BiO[ClBrI(CO3)0.5] materials using a simple coprecipitation method. It was found that adjusting the number of anions in the anion layer was conducive to adjusting the band structure of BiOX and could effectively promote the migration and separation of photogenerated carriers, thus improving the photocatalytic activity. We first selected methyl orange (MO) as the study pollutant and compared it with BiOCl, BiO(ClBr), and BiO(ClBrI). The first-order kinetic constants of MO degradation by BiO[ClBrI(CO3)0.5] increased by 90.3, 33.9, and 3.1 times, respectively. The photocatalytic degradation rate of methylene blue by BiO[ClBrI(CO3)0.5] was 89.5%, indicating the excellent photocatalytic performance of BiO[ClBrI(CO3)0.5]. The stability of BiO[ClBrI(CO3)0.5] was demonstrated through cyclic experiments and XRD analysis before and after the reaction. The photocatalytic degradation of MO by BiO[ClBrI(CO3)0.5] showed that h+ and 1O2 were the main active oxidizing species and •O2- was the secondary active substance. Overall, our work provides new ideas for the synthesis and degradation of organic pollutants by using two-dimensional anionic high-entropy materials.

4.
J Org Chem ; 89(6): 4134-4144, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38394632

RESUMEN

Base-catalyzed diastereodivergent and regioselective domino processes of triketone enones with arylacetaldehydes for the synthesis of tetrahydrofuro[2,3-b]furans with four consecutive stereocenters are reported. Good yields and diastereoselectivities are obtained when DBU is employed as a catalyst; in contrast, Et3N delivers a different diastereomer in excellent diastereoselectivity. This work offers many advantages, including switchable diastereoselectivity, cheap base catalysts, and a simple operation.

5.
J Am Chem Soc ; 145(10): 5769-5777, 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36863033

RESUMEN

A series of novel surface Ru-H bipyridine complexes-grafted TiO2 nanohybrids were for the first time prepared by a combined procedure of surface organometallic chemistry with post-synthetic ligand exchange for photocatalytic conversion of CO2 to CH4 with H2 as electron and proton donors under visible light irradiation. The selectivity toward CH4 increased to 93.4% by the ligand exchange of 4,4'-dimethyl-2,2'-bipyridine (4,4'-bpy) with the surface cyclopentadienyl (Cp)-RuH complex and the CO2 methanation activity was enhanced by 4.4-fold. An impressive rate of 241.2 µL·g-1·h-1 for CH4 production was achieved over the optimal photocatalyst. The femtosecond transient IR absorption results demonstrated that the hot electrons were fast injected in 0.9 ps from the photoexcited surface 4,4'-bpy-RuH complex into the conduction band of TiO2 nanoparticles to form a charge-separated state with an average lifetime of ca. 50.0 ns responsible for the CO2 methanation. The spectral characterizations indicated clearly that the formation of CO2•- radicals by single electron reduction of CO2 molecules adsorbed on surface oxygen vacancies of TiO2 nanoparticles was the most critical step for the methanation. Such radical intermediates were inserted into the explored Ru-H bond to generate Ru-OOCH species and finally CH4 and H2O in the presence of H2.

6.
Pol J Pathol ; 74(4): 232-247, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38477085

RESUMEN

Single-minded homolog 2 (SIM2) has been identified as a potential contributor to the development of solid tumors. Despite this, there is a lack of comprehensive research regarding its biological role and underlying mechanism within pancreatic cancer (PC), as well as its prognostic impact. This study systematically evaluated the expression level and clinical significance of SIM2 in patients with PC using various databases, including The Cancer Genome Atlas, KM Plotter, and gene expression profiling interactive analysis. To investigate the relationship between SIM2 expression and immune cell infiltration, we conducted ESTIMATE and single-sample gene set enrichment analysis (ssGSEA) analyses. Single-minded homolog 2 was up-regulated in patients with PC. Pancreatic cancer patients with higher SIM2 expression had poorer overall survival rates. Gene set enrichment analysis results suggested that SIM2 may have a significant impact on the progression of PC and the regulation of immune responses. According to the ssGSEA algorithm, SIM2 has a negative correlation with the levels of infiltrating TFH, mast cells, and pDC. Our study demonstrated that SIM2 serves as a biomarker, and is associated with both prognosis and immune infiltration in PC. This provides a solid foundation for future investigations into the precise role of SIM2 in the carcinogenesis and progression of PC.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico , Neoplasias Pancreáticas , Humanos , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Pronóstico , Perfilación de la Expresión Génica
7.
Angew Chem Int Ed Engl ; 62(36): e202309026, 2023 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-37460792

RESUMEN

The keto-switched photocatalysis of covalent organic frameworks (COFs) for efficient H2 evolution was reported for the first time by engineering, at a molecular level, the local structure and component of the skeletal building blocks. A series of imine-linked BT-COFs were synthesized by the Schiff-base reaction of 1, 3, 5-benzenetrialdehyde with diamines to demonstrate the structural reconstruction of enol to keto configurations by alkaline catalysis. The keto groups of the skeletal building blocks served as active injectors, where hot π-electrons were provided to Pt nanoparticles (NPs) across a polyvinylpyrrolidone (PVP) insulting layer. The characterization results, together with density functional theory calculations, indicated clearly that the formation of keto-injectors not only made the conduction band level more negative, but also led to an inhomogeneous charge distribution in the donor-acceptor molecular building blocks to form a strong intramolecular built-in electric field. As a result, visible-light photocatalysis of TP-COFs-1 with one keto group in the skeletal building blocks was successfully enabled and achieved an impressive H2 evolution rate as high as 0.96 mmol g-1 h-1 . Also, the photocatalytic H2 evolution rates of the reconstructed BT-COFs-2 and -3 with two and three keto-injectors were significantly enhanced by alkaline post-treatment.

8.
Zhongguo Dang Dai Er Ke Za Zhi ; 25(10): 995-1000, 2023 Oct 15.
Artículo en Zh | MEDLINE | ID: mdl-37905754

RESUMEN

OBJECTIVES: To explore the effects of somatostatin on the levels of gastrointestinal hormones and clinical outcomes in critically ill infants after gastrointestinal surgery. METHODS: Using a random number table method, critically ill infants after gastrointestinal surgery who were admitted to the Intensive Care Unit of Xuzhou Children's Hospital from June 2019 to June 2021 were randomly divided into an observation group (29 cases) and a control group (30 cases). The control group received routine treatment such as anti-infection and hemostasis after surgery, while the observation group received somatostatin in addition to the routine treatment [3.5 µg/(kg·h) infusion for 7 days]. The levels of serum gastrin (GAS), motilin (MTL), insulin, and glucagon-like peptide-1 (GLP-1) before surgery, on the 3rd day after surgery, and on the 7th day after surgery were compared between the two groups. The recovery progress and incidence of complications after surgery were also compared between the two groups. RESULTS: There was no significant difference in the levels of serum GAS, MTL, insulin, and GLP-1 between the two groups before surgery (P>0.05). On the 3rd and 7th day after surgery, the levels of serum GAS, MTL, insulin, and GLP-1 in the observation group were higher than those in the control group (P<0.05). In the observation group, the levels of GAS, MTL, insulin, and GLP-1 on the 7th day after surgery were higher than those before surgery and on the 3rd day after surgery (P<0.05), and the levels on the 3rd day after surgery were higher than those before surgery (P<0.05). There was no significant difference in the levels of serum GAS, MTL, and insulin before surgery, on the 3rd day after surgery, and on the 7th day after surgery in the control group (P>0.05). The level of GLP-1 on the 7th day after surgery was higher than that before surgery and on the 3rd day after surgery (P<0.05), and the level on the 3rd day after surgery was higher than that before surgery (P<0.05) in the control group. The observation group had shorter first time of anal exhaust, recovery time of bowel sounds, and first time of defecation after surgery compared to the control group (P<0.05). The incidence of complications after surgery in the observation group was lower than that in the control group (10% vs 33%, P<0.05). CONCLUSIONS: Somatostatin can increase the levels of serum GAS, MTL, insulin, and GLP-1 in critically ill infants after gastrointestinal surgery, promote the recovery of gastrointestinal function, and reduce the incidence of postoperative complications.


Asunto(s)
Procedimientos Quirúrgicos del Sistema Digestivo , Humanos , Lactante , Enfermedad Crítica , Péptido 1 Similar al Glucagón , Insulina , Estudios Prospectivos , Somatostatina/uso terapéutico
9.
BMC Infect Dis ; 22(1): 868, 2022 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-36411430

RESUMEN

BACKGROUND: Human brucellosis has become one of the major public health problems in China, and increases atypical manifestations, such as fever of unknown origin (FUO), and misdiagnosis rates has complicated the diagnosis of brucellosis. To date, no relevant study on the relationship between brucellosis and FUO has been conducted. METHODS: We retrospectively reviewed the medical charts of 35 patients with confirmed human brucellosis and prospectively recorded their outcomes by telephone interview. The patients were admitted to the Second Affiliated Hospital of Nanchang University between January 01, 2013 and October 31, 2019. Patient data were collected from hospital medical records. RESULTS: The percentage of males was significantly higher than that of female in FUO (78.95% vs. 21.05%, P < 0.05), and 80% of the patients had a clear history of exposure to cattle and sheep. Moreover, 19 (54%) cases were hospitalized with FUO, among which the patients with epidemiological histories were significantly more than those without (P < 0.05). The incidence of toxic hepatitis in FUO patients was higher than that in non-FUO patients (89% vs. 50%, P < 0.05). Meanwhile, the misdiagnosis rate was considerably higher in the FUO group than in the non-FUO group (100% vs. 63%; P < 0.05). CONCLUSION: Brucellosis is predominantly FUO admission in a non-endemic area of China, accompanied by irregular fever and toxic hepatitis. Careful examination of the epidemiological history and timely improvement of blood and bone marrow cultures can facilitate early diagnosis and prevent misdiagnosis.


Asunto(s)
Brucelosis , Enfermedad Hepática Inducida por Sustancias y Drogas , Fiebre de Origen Desconocido , Masculino , Humanos , Femenino , Bovinos , Ovinos , Animales , Fiebre de Origen Desconocido/diagnóstico , Fiebre de Origen Desconocido/epidemiología , Fiebre de Origen Desconocido/etiología , Estudios Retrospectivos , Brucelosis/complicaciones , Brucelosis/diagnóstico , Brucelosis/epidemiología , Hospitalización
10.
Cell Mol Biol (Noisy-le-grand) ; 67(5): 81-87, 2022 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-35818268

RESUMEN

LETMD1 is a differentially expressed gene selected by scientists from cervical cancer (CC) tissues by RT-PCR technology. It has been confirmed that LETMD1 is overexpressed in many human malignant tumors, so it can be used as an early diagnostic marker for malignant tumors and as a target for gene therapy. The purpose of this article is to further explore the effectiveness of miR-494 in inhibiting the proliferation, migration and invasion of CC cells by regulating LETMD1, selecting 40 cases of CC admitted to a hospital from June 2015 to September 2018 Patients, tumor tissue specimens were taken from the primary tumor tissue of CC, and normal tissues near the cutting edge were collected as controls. Normal tissues were confirmed by pathology after surgery that they were not invaded by cancer tissues. The results of the study showed that the expression level of miR-494 increased by 15%, and the prognostic survival rate after surgery increased by 20%, depending on gender, age, tumor size, and tumor site. After high expression of miR-494 in CC patients, the vascular invasion of CC cells was reduced by 33%, and distant metastasis was reduced by 11%, and the survival time of patients was significantly prolonged. After the expression of LETMD1, the proportion of cancer cells decreased by 5%, the proportion of macrophages increased by 2%, and the dendritic cells increased by 3%.


Asunto(s)
MicroARNs , Proteínas Proto-Oncogénicas , Neoplasias del Cuello Uterino , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , MicroARNs/genética , Proteínas Proto-Oncogénicas/genética , Neoplasias del Cuello Uterino/genética , Neoplasias del Cuello Uterino/patología
11.
Zhongguo Zhong Yao Za Zhi ; 47(9): 2525-2532, 2022 May.
Artículo en Zh | MEDLINE | ID: mdl-35531700

RESUMEN

Dendrobium officinale can serve as Chinese medicinal material effective in nourishing yin, clearing heat, and producing fluid, and is used to treat throat diseases, but its active substances and mechanism are not clear. To clarify the active fraction and underlying mechanism of D. officinale against chronic pharyngitis(CP), the present study induced a CP model in rats by pepper water combined with low-concentration ammonia, and crude polysaccharides of D. officinale(DOP), non-polysaccharides of D. officinale(DON), and total extract of D. officinale(DOT)(0.33 g·kg~(-1), calculated according to the crude drug) were administered by gavage for six weeks. The changes in oral secretions and pharyngeal conditions of rats with CP were observed and rated. The hematological indicators were determined by an automatic hematology analyzer. The serum levels of pro-inflammatory factors, such as tumor necrosis factor-alpha(TNF-α), interleukin 1ß(IL-1ß), and interleukin 6(IL-6), and T-lymphocyte cytokines, including interferon γ(IFN-γ), interleukin 4(IL-4), interleukin 17(IL-17), and transforming growth factor ß1(TGF-ß1) were detected by the enzyme-linked immunosorbent assay(ELISA). The proportions of CD3~+, CD4~+, and CD8~+cells in peripheral blood T lymphocyte subsets were determined by the flow cytometry. The histomorphological changes of the pharynx were observed by hematoxylin-eosin(HE) staining. The protein expression of nuclear factor-κB P65(NF-κB P65), cyclooxygenase-2(COX-2), F4/80, and monocyte chemoattractant protein-1(MCP-1) in the pharynx were detected by immunohistochemistry and Western blot. The results showed that DOP and DON could significantly relieve pharyngeal lesions, reduce white blood cells(WBC) and lymphocytes(LYMP), decrease the levels of pro-inflammatory factors TNF-α, IL-6, and IL-1ß, and inhibit the protein expression of NF-κB P65, COX-2, F4/80, and MCP-1 in the pharynx. DOP was superior in reducing oral secretions and serum IL-17 level and inferior in increasing CD4~+/CD8~+ratio to DON. It is suggested that both polysaccharides and non-polysaccharides of D. officinale have anti-PC effects and the anti-inflammatory mechanism may be related to the regulation of T lymphocyte distribution and inhibition of the inflammatory signaling pathways mediated by NF-κB P65. The anti-inflammatory effect of DOP may be related to the regulation of Th17/Treg balance, while that of DON may be related to the regulation of the Th/Tc ratio.


Asunto(s)
Dendrobium , Faringitis , Amoníaco/uso terapéutico , Animales , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Ciclooxigenasa 2 , Dendrobium/química , Interleucina-17/uso terapéutico , Interleucina-6 , FN-kappa B/metabolismo , Faringitis/tratamiento farmacológico , Extractos Vegetales/química , Polisacáridos/farmacología , Ratas , Factor de Necrosis Tumoral alfa , Agua
12.
Zhongguo Dang Dai Er Ke Za Zhi ; 24(7): 812-816, 2022 Jul 15.
Artículo en Zh | MEDLINE | ID: mdl-35894198

RESUMEN

OBJECTIVES: To study the effect of somatostatin on postoperative gastrointestinal function and stress level in children with acute abdomen. METHODS: A total of 102 children with acute abdomen who underwent surgery in Xuzhou Children's Hospital from August 2019 to June 2021 were enrolled as subjects and were randomly divided into an observation group and a control group, with 51 children in each group. The children in the control group were given conventional treatment such as hemostasis and anti-infective therapy after surgery, and those in the observation group were given somatostatin in addition to conventional treatment. Peripheral blood samples were collected from both groups before surgery and on days 1 and 5 after surgery. The two groups were compared in terms of the serum levels of endothelin-1 (ET-1), adrenocorticotropic hormone (ACTH), cortisol, gastrin, and motilin, postoperative recovery, and the incidence rate of complications. RESULTS: There was no significant difference in the serum levels of ET-1, ACTH, cortisol, gastrin, and motilin between the two groups before surgery (P>0.05). Compared with the control group, the observation group had significantly lower serum levels of ET-1, ACTH, and cortisol on days 1 and 5 after surgery (P<0.05) and significantly higher levels of motilin and gastrin on day 5 after surgery (P<0.05). Compared with the control group, the observation group had significantly shorter time to first passage of flatus, first bowel sounds, and first defecation after surgery, as well as a significantly shorter length of hospital stay (P<0.05). The incidence rate of complications in the observation group was significantly lower than that in the control group (6% vs 24%, P<0.05). CONCLUSIONS: In children with acute abdomen, somatostatin can significantly reduce postoperative stress response, improve gastrointestinal function, and reduce the incidence rate of complications, thereby helping to achieve a good prognosis.


Asunto(s)
Abdomen Agudo , Motilina , Abdomen , Hormona Adrenocorticotrópica , Niño , Gastrinas , Humanos , Hidrocortisona , Complicaciones Posoperatorias , Estudios Prospectivos , Somatostatina/uso terapéutico
13.
Int J Cancer ; 148(3): 692-701, 2021 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-32700765

RESUMEN

Although receptor status including estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2) of the primary breast tumors was related to the prognosis of breast cancer patients, little information is yet available on whether patient management and survival are impacted by receptor conversion in breast cancer metastases. Using data from the nation-wide multicenter clinical epidemiology study of advanced breast cancer in China (NCT03047889), we report the situation of retesting ER, PR and HER2 status for breast cancer metastases and evaluate the patient management and prognostic value of receptor conversion. In total, 3295 patients were analyzed and 1583 (48.0%) patients retesting receptor status for metastasis. Discordance in one or more receptors between the primary and the metastatic biopsy was found in 37.7% of women. Patients who remained hormone receptor (HR) positive in their metastases had similar progression-free survival of first-line and second-line treatment compared to patients with HR conversion (P > .05). In multivariate analysis, patients who showed ER conversion from negative to positive had longer disease-free survival (DFS) than patients who remained negative in their metastases (hazard ratio, 2.05; 95% confidence interval [CI], 1.45-2.90; P < .001). Patients with PR remained positive and had longer DFS than patients with PR conversion from negative to positive (hazard ratio, 0.56; 95% CI, 0.38-0.83; P = .004). Patients with PR conversion have shorter overall survival than patients with PR remained positive or negative (P = .016 and P = .041, respectively). Our findings showed that the receptors' conversions were common in metastatic breast cancer, and the conversion impacted the survival.


Asunto(s)
Neoplasias de la Mama/mortalidad , Receptor ErbB-2/metabolismo , Receptores de Estrógenos/metabolismo , Receptores de Progesterona/metabolismo , Neoplasias de la Mama/metabolismo , Supervivencia sin Enfermedad , Estudios Epidemiológicos , Femenino , Humanos , Análisis Multivariante , Metástasis de la Neoplasia , Pronóstico , Estudios Retrospectivos
14.
BMC Cancer ; 21(1): 651, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-34074258

RESUMEN

OBJECTIVE: Plasma Epstein-Barr virus (EBV) DNA is considered a biomarker for nasopharyngeal carcinoma (NPC). However, its long-term role in NPC development is unclear. MATERIALS AND METHODS: A total of 1363 participants seropositive for EBV VCA-IgA and EBNA1-IgA in a community-based NPC screening program in southern China were tested for plasma EBV DNA levels by real-time qPCR between 2008 and 2015. New NPC cases were confirmed by active follow-up approach and linkage to local cancer registry through the end of 2016. Cox proportional hazards regression analysis was performed to calculate the hazard ratios (HRs) for NPC risk with plasma EBV DNA. RESULTS: Thirty patients were newly diagnosed during a median 7.5 years follow-up. NPC incidence increased with the plasma EBV DNA load ranging from 281.46 to 10,074.47 per 100,000 person-years in participants with undetectable and ≥ 1000 copies/ml levels; the corresponding cumulative incidence rates were 1.73 and 50%. Furthermore, plasma EBV DNA loads conferred an independent risk for NPC development after adjustment for other risk factors, with HRs of 7.63 for > 3-999 copies/ml and 39.79 for ≥1000 copies/ml. However, the HRs decreased gradually after excluding NPC cases detected in the first 2 to 3 years and became statistically nonsignificant by excluding cases detected during the first 4 years. CONCLUSION: Elevated plasma EBV DNA can predict NPC risk over 3 years. Monitoring plasma EBV DNA can be used as a complementary approach to EBV serological antibody-based screening for NPC.


Asunto(s)
Biomarcadores de Tumor/sangre , ADN Viral/sangre , Infecciones por Virus de Epstein-Barr/epidemiología , Carcinoma Nasofaríngeo/epidemiología , Neoplasias Nasofaríngeas/epidemiología , Adulto , Anciano , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , Antígenos Virales/inmunología , Proteínas de la Cápside/inmunología , Infecciones por Virus de Epstein-Barr/sangre , Infecciones por Virus de Epstein-Barr/diagnóstico , Infecciones por Virus de Epstein-Barr/virología , Femenino , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/inmunología , Herpesvirus Humano 4/aislamiento & purificación , Humanos , Masculino , Persona de Mediana Edad , Carcinoma Nasofaríngeo/sangre , Carcinoma Nasofaríngeo/diagnóstico , Carcinoma Nasofaríngeo/virología , Neoplasias Nasofaríngeas/sangre , Neoplasias Nasofaríngeas/diagnóstico , Neoplasias Nasofaríngeas/virología , Estudios Prospectivos , Reacción en Cadena en Tiempo Real de la Polimerasa , Factores de Riesgo , Pruebas Serológicas/estadística & datos numéricos
15.
J Pept Sci ; 27(5): e3306, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33554385

RESUMEN

In this article, a series of modifications were made on an antimicrobial peptide F2,5,12 W, including altering the amino acid sequence, introducing cysteine and other typical amino acids, developing peptide dimers via disulfide bonds, and conjugating with mPEG, in order to enhance the antimicrobial activity, plasma stability, and reduce the hemolytic activity of peptides. The results showed that mPEG conjugation could significantly improve the plasma stability and reduce the hemolytic activity of peptides, while the antimicrobial activity decreased meanwhile. However, altering the sequence of the peptide without changing its amino acid composition had little impact on its antimicrobial activity and plasma stability. The introduction of cysteine enhanced the plasma stability of peptides conspicuously, but at the same time, the increased hydrophobicity of peptides increased their hemolysis. The antimicrobial mechanism and cytotoxicity of the peptides with relatively high antimicrobial activity were also studied. In general, this study provided some ideas for the rational design and structure optimization of antimicrobial peptides.


Asunto(s)
Antibacterianos/farmacología , Escherichia coli/efectos de los fármacos , Proteínas Citotóxicas Formadoras de Poros/farmacología , Staphylococcus aureus/efectos de los fármacos , Antibacterianos/sangre , Antibacterianos/química , Hemólisis/efectos de los fármacos , Humanos , Pruebas de Sensibilidad Microbiana , Proteínas Citotóxicas Formadoras de Poros/sangre , Proteínas Citotóxicas Formadoras de Poros/química
16.
Zhongguo Zhong Yao Za Zhi ; 46(14): 3650-3659, 2021 Jul.
Artículo en Zh | MEDLINE | ID: mdl-34402289

RESUMEN

Puerarin has the anti-Alzheimer's disease (AD) activity,which can reverse nerve injury induced by Aßand inhibit neuronal apoptosis.However,its potential pharmacodynamic mechanism still needs to be further researched.The occurrence and development of AD is due to the change of multiple metabolic links in the body,which leads to the destruction of balance.Puerarin may act on multiple targets and multiple metabolic processes to achieve therapeutic purposes.Quantitative proteomic analysis provides a new choice to understand the mechanism as completely as possible.This research adopted SH-SY5Y cells induced by Aß_(1-42)to establish AD cell model,and Aßimmunofluorescence detection showed that Aßdecreased significantly after puerarin intervention.The mechanism of puerarin reversing SH-SY5Y cell injured by Aß_(1-42)was further explored by using label-free non-labeled quantitative technology and Western blot detection based on bioinformatics analysis result.The results showed that most of the differential proteins were related to biological processes such as cellular component organization or biogenesis,cellular component organization and cellular component biogenesis,and they mainly participated in the top ten pathways of P value such as pathogenic Escherichia coli infection,m TOR signaling pathway,regulation of autophagy,regulation of actin cytoskeleton,spliceosome,hepatocellular carcinoma,tight junction,non-small cell lung cancer,apoptosis and gap junction.Annexin V/PI flow cytometry and TUNEL were used to detect apoptosis,and the results showed that Aßdecreased significantly and the rate of apoptosis decreased significantly after puerarin intervention.Western blot analysis found that the protein expression level of autophagy related protein LC3Ⅱwas up-regulated after Aßinduction,and the degree of this up-regulation was further enhanced in puerarin intervention group.The trend of the ratio of LC3Ⅱ/LC3Ⅰamong groups was the same as the protein expression level of LC3Ⅱ,the protein expression level of p62 in the control group,AD model group and puerarin intervention group decreased successively.Protein interaction network analysis showed that CAP1 was correlated with TUBA1B,HSP90AB2P,DNM1L,TUBA1A and ERK1/2,and the correlation between CAP1 and ERK1/2 was the highest among them.Western blot showed that the expressions of p-ERK1/2,Bax and CAP1 were significantly down-regulated and the protein expression level of Bcl-2 was significantly up-regulated after puerarin intervention.Therefore,puerarin might improve the SH-SY5Y cells injured by Aß_(1-42)through the interaction of multiple biological processes and pathways in cells multiple locations,and CAP1 might play an important role among them.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Isoflavonas , Neoplasias Pulmonares , Péptidos beta-Amiloides , Apoptosis , Línea Celular Tumoral , Humanos , Isoflavonas/farmacología , Proteómica
17.
Curr Microbiol ; 77(11): 3492-3503, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32929577

RESUMEN

Nitrospira is the most diverse genus of nitrite-oxidizing bacteria, and its members are widely spread in various natural and engineered ecosystems. In this study, the phylogenetic diversity of Nitrospira and monthly changes of its abundance from Zhanjiang Bay were investigated. Phylogenetic analysis showed that among 58 OTUs with high abundance, 74% were not affiliated with any previously described Nitrospira species, revealing a previously unrecognized diversity of coastal Nitrospira. The abundances of both Nitrospira and Nitrospina exhibited a significantly monthly change. During most of the months, abundance of Nitrospina was greater than that of Nitrospira. In particle-attached communities, either abundance of Nitrospina or Nitrospira was highly correlated with that of ammonia-oxidizing archaea (AOA), whereas abundance of ammonia-oxidizing bacteria was only highly correlated with that of Nitrospina. In free-living communities, either abundance of Nitrospina or Nitrospira was correlated only with that of AOA. These results suggest that both Nitrospira and Nitrospina can be involved in nitrite oxidation by coupling with AOA, but Nitrospina may play a greater role than Nitrospira in this tropical bay.


Asunto(s)
Ecosistema , Microbiología del Suelo , Amoníaco , Archaea/genética , Bacterias/genética , Bahías , Nitrificación , Oxidación-Reducción , Filogenia
18.
Entropy (Basel) ; 22(11)2020 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-33286980

RESUMEN

The purpose of this study is to analyze the dynamic properties of gas hydrate development from a large hydrate simulator through numerical simulation. A mathematical model of heat transfer and entropy production of methane hydrate dissociation by depressurization has been established, and the change behaviors of various heat flows and entropy generations have been evaluated. Simulation results show that most of the heat supplied from outside is assimilated by methane hydrate. The energy loss caused by the fluid production is insignificant in comparison to the heat assimilation of the hydrate reservoir. The entropy generation of gas hydrate can be considered as the entropy flow from the ambient environment to the hydrate particles, and it is favorable from the perspective of efficient hydrate exploitation. On the contrary, the undesirable entropy generations of water, gas and quartz sand are induced by the irreversible heat conduction and thermal convection under notable temperature gradient in the deposit. Although lower production pressure will lead to larger entropy production of the whole system, the irreversible energy loss is always extremely limited when compared with the amount of thermal energy utilized by methane hydrate. The production pressure should be set as low as possible for the purpose of enhancing exploitation efficiency, as the entropy production rate is not sensitive to the energy recovery rate under depressurization.

19.
Microb Pathog ; 130: 213-218, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30862559

RESUMEN

OBJECTIVES: The host immune response could be an imperative factor in the pathogenesis of neurosyphilis, but the role of T lymphocyte subsets remains unclear. In the present study, we assessed the CD4+ T and CD8+ T cell subsets in the peripheral blood of patients with HIV-negative symptomatic neurosyphilis and then explored the clinical application value of neurosyphilis. METHODS: In total, 24 patients with HIV-negative symptomatic neurosyphilis and 22 patients with syphilis/non-neurosyphilis were included in this study and cerebrospinal fluid (CSF) and blood samples were obtained. Th1, Th2, Th17, Th9, CD8+IFN-γ+, CD8+IL-4+, CD8+IL-9+, and CD8+IL-17 + cells were identified by flow cytometry. RESULTS: The levels of CD8+IFN-γ+ were significantly increased in the peripheral blood of neurosyphilis patients compared to that in syphilis/non-neurosyphilis patients, but it was opposite to Th2, Th9, CD8+IL-4+, CD8+IL-9+, and CD8+IL-17 + cells. Dendritic cells (DCs) of neurosyphilis matured by T. pallidum induced the development of a combination of IFN-γ-producing Th1 cells. The number of CD8+IL-17 + cells was significantly correlated with the CSF RPR and CSF TPPA levels. ROC curve analysis revealed that the number of CD8+IFN-γ+ cells could be a potential biomarker for neurosyphilis from non-neurosyphilis/syphilis. CONCLUSIONS: High expression of CD8+IFN-γ+ cells and low expression of CD8+IL-17 + cells in patients with symptomatic neurosyphilis, which explains the pathogenesis of symptomatic neurosyphilis, meanwhile CD8+IFN-γ+ cells may be a better indicator in classifying symptomatic neurosyphilis from non-neurosyphilis/syphilis among patients without HIV infection.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Neurosífilis/patología , Subgrupos de Linfocitos T/inmunología , Adulto , Anciano , Células Sanguíneas , Líquido Cefalorraquídeo/citología , Femenino , Citometría de Flujo , Humanos , Masculino , Persona de Mediana Edad
20.
Environ Monit Assess ; 191(11): 678, 2019 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-31654145

RESUMEN

Although grassland degradation simultaneously affects plant productivity and soil nutrient concentrations, the relationship between plant productivity and soil nutrient concentrations during the process of grassland degradation is not yet well documented. A 4-year survey in the Qinghai-Tibetan Plateau was conducted to simultaneously investigate the relationships between plant productivity and soil nutrient concentrations in an alpine grassland at an overall degradation level and individual degradation levels. Our results showed that the total plant, sedge, and forb biomasses decreased, whereas the grass and legume biomasses first increased and then decreased as the level of alpine grassland degradation increased. Soil organic carbon (C), total nitrogen (N), total phosphorus (P), available N, and available P concentrations also decreased with the increase in degradation level. Our results also showed that plant productivity was positively correlated with soil nutrient concentrations (soil organic C, total T, total P, available N, available P) at an overall degradation level, whereas plant productivity was positively correlated with only the soil organic C concentration at each degradation level. Our findings suggested that the alpine grassland degradation conditions had different effects on the plant productivity of four functional groups (sedges, grasses, legumes, forbs) and affected the relationship between plant productivity and soil nutrient concentrations.


Asunto(s)
Monitoreo del Ambiente , Pradera , Biomasa , Carbono/metabolismo , Ecosistema , Nitrógeno/análisis , Nutrientes , Fósforo/análisis , Plantas/metabolismo , Poaceae/metabolismo , Suelo
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