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1.
RNA ; 28(9): 1210-1223, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35750488

RESUMEN

Dengue virus, a single-stranded positive sense RNA virus, is the most prevalent mosquito-borne pathogen in the world. Like all RNA viruses, it uses conserved structural elements within its genome to control essential replicative steps. A 70 nt stem-loop RNA structure (called SLA), found at the 5'-end of the genome of all flaviviruses, functions as the promoter for viral replication. This highly conserved structure interacts with the viral polymerase NS5 to initiate RNA synthesis. Here, we report the NMR structure of a monomeric SLA from dengue virus serotype 1, assembled to high-resolution from independently folded structural elements. The DENV1 SLA has an L-shaped structure, where the top and side helices are coaxially stacked, and the bottom helix is roughly perpendicular to them. Because the sequence is highly conserved among different flavivirus genomes, it is very likely that the three-dimensional fold and local structure of SLA are also conserved among flaviviruses and required for efficient replication. This work provides structural insight into the dengue promoter and provides the foundation for the discovery of new antiviral drugs that target this essential replicative step.


Asunto(s)
Virus del Dengue , Animales , Virus del Dengue/genética , Regiones Promotoras Genéticas , ARN Viral/química , ARN Viral/genética , Replicación Viral/genética
2.
J Nanobiotechnology ; 22(1): 244, 2024 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-38735969

RESUMEN

Biomaterials can modulate the local immune microenvironments to promote peripheral nerve regeneration. Inspired by the spatial orderly distribution and endogenous electric field of nerve fibers, we aimed to investigate the synergistic effects of electrical and topological cues on immune microenvironments of peripheral nerve regeneration. Nerve guidance conduits (NGCs) with aligned electrospun nanofibers were fabricated using a polyurethane copolymer containing a conductive aniline trimer and degradable L-lysine (PUAT). In vitro experiments showed that the aligned PUAT (A-PUAT) membranes promoted the recruitment of macrophages and induced their polarization towards the pro-healing M2 phenotype, which subsequently facilitated the migration and myelination of Schwann cells. Furthermore, NGCs fabricated from A-PUAT increased the proportion of pro-healing macrophages and improved peripheral nerve regeneration in a rat model of sciatic nerve injury. In conclusion, this study demonstrated the potential application of NGCs in peripheral nerve regeneration from an immunomodulatory perspective and revealed A-PUAT as a clinically-actionable strategy for peripheral nerve injury.


Asunto(s)
Macrófagos , Regeneración Nerviosa , Traumatismos de los Nervios Periféricos , Poliuretanos , Ratas Sprague-Dawley , Células de Schwann , Animales , Regeneración Nerviosa/efectos de los fármacos , Poliuretanos/química , Ratas , Macrófagos/efectos de los fármacos , Células de Schwann/efectos de los fármacos , Nanofibras/química , Nervio Ciático/efectos de los fármacos , Regeneración Tisular Dirigida/métodos , Masculino , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Andamios del Tejido/química , Ratones , Células RAW 264.7
3.
Bull World Health Organ ; 101(5): 317-325A, 2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-37131940

RESUMEN

Objective: To measure sales of antibiotics without a prescription in pharmacies in China in 2017 and 2021, before and during the coronavirus disease 2019 (COVID-19) pandemic, and determine the factors associated with such sales. Methods: We conducted cross-sectional surveys using the simulated patient method in retail pharmacies in 13 provinces in eastern, central and western China in 2017 and 2021. At the pharmacies, the simulated patients (trained medical students) reported that they had mild respiratory tract symptoms and asked for treatment, using a three-stage process: (i) request some treatment; (ii) request antibiotics; (iii) request specific antibiotics. We used multivariable logistic regression analysis to determine factors associated with sale of antibiotics without a prescription. Findings: Of the pharmacies visited in 2017, 83.6% (925/1106) sold antibiotics without a prescription; this figure was 78.3% (853/1090) in 2021 (P-value: 0.002). After excluding pharmacies prohibited from selling antibiotics because of COVID-19, this difference was not significant (83.6% versus 80.9%; 853/1054; P-value: 0.11). Factors significantly associated with selling antibiotics without a prescription in both 2017 and 2019 were: location in central and western China compared with eastern China; being in a township or village compared with in a city; and presence of a counter where antibiotics were dispensed. Conclusion: Although laws became stricter between 2017 and 2021, antibiotic sales without a prescription were still common in pharmacies across China. Existing regulations need to be more strictly enforced, and pharmacy staff and the public should be made more aware of the risks of antibiotic misuse and dangers of antimicrobial resistance.


Asunto(s)
Antibacterianos , Farmacias , Humanos , Antibacterianos/uso terapéutico , China , COVID-19/epidemiología , Estudios Transversales , Prescripciones , Comercio
4.
Medicina (Kaunas) ; 59(6)2023 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-37374227

RESUMEN

Background and Objectives: The current study aimed to better understand the changes in respiration that occur with aging in men and women to provide accurate recommendations for breathing exercises to improve health. Materials and Methods: A total of 610 healthy subjects, aged 20 to 59, participated in the study. They performed quiet breathing while wearing two respiration belts (Vernier, Beaverton, OR, USA) at the height of the navel and at the xiphoid process to record abdominal motion (AM) and thoracic motion (TM), respectively. Vital capacity, representing maximal inhalation movement, was measured using a spirometer (Xindonghuateng, Beijing, China). After exclusion, 565 subjects (164 men, aged 41 ± 11; 401 women, aged 42 ± 9) were included for statistical analysis using the Kruskal-Wallis U test and stepwise multiple linear regression. Results: Abdominal motion and its contribution to spontaneous breathing were significantly larger for older men, while the contribution of thoracic motion was smaller for older men. There was no significant difference in thoracic motion between the younger and older men. The differences in women's respiratory movements among various ages were mild and negligible. The contribution of thoracic motion to spontaneous breathing in women was larger than in men for those of older ages (40-59 years), but not for those of younger ages (20-39 years). Additionally, men's and women's vital capacities were less in those of older ages, and the men's were larger than the women's. Conclusions: The findings indicate that men's abdominal contribution to spontaneous breathing increased from 20 to 59 years of age due to increased abdominal motion. Women's respiratory movements did not change much with aging. The maximal inhalation movement became smaller with aging for men and women. Healthcare professionals should focus on improving thoracic mobility when addressing health concerns about aging.


Asunto(s)
Movimiento , Respiración , Masculino , Humanos , Femenino , Anciano , Adulto Joven , Adulto , Persona de Mediana Edad , Abdomen , Análisis Multivariante , China
5.
Int J Mol Sci ; 23(2)2022 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-35054767

RESUMEN

Cyclanilide (CYC), a plant growth regulator, is a potent shoot branching agent in apple. However, its mechanism remains unclear. The current study revealed that CYC treatment resulted in massive reprogramming of the axillary bud transcriptome, implicating several hormones in the response. We observed a marked increase (approximately 2-fold) in the level of zeatin riboside and a significant decrease (approximately 2-fold) in the level of abscisic acid (ABA). Zeatin metabolism gene cytokinin (CTK) oxidase 1 (CKX 1) was down-regulated at 168 h after CYC treatment compared with the control. Weighted gene co-expression network analysis of differentially expressed genes demonstrated the turquoise module clusters exhibited the highest positive correlation with zeatin riboside (r = 0.92) and the highest negative correlation with ABA (r = -0.8). A total of 37 genes were significantly enriched in the plant hormone signal transduction pathway in the turquoise module. Among them, the expressions of CTK receptor genes WOODEN LEG and the CTK type-A response regulators genes ARR3 and ARR9 were up-regulated. ABA signal response genes protein phosphatase 2C genes ABI2 and ABI5 were down-regulated in lateral buds after CYC treatment at 168 h. In addition, exogenous application of 6-benzylaminopurine (6-BA, a synthetic type of CTK) and CYC enhanced the inducing effect of CYC, whereas exogenous application of lovastatin (a synthetic type of inhibitor of CTK biosynthesis) or ABA and CYC weakened the promoting effect of CYC. These results collectively revealed that the stimulation of bud growth by CYC might involve CTK biosynthesis and signalling, including genes CKX1 and ARR3/9, which provided a direction for further study of the branching promoting mechanism of CYC.


Asunto(s)
Berberina/análogos & derivados , Citocininas/metabolismo , Malus/metabolismo , Transducción de Señal , Ácido Abscísico/metabolismo , Berberina/metabolismo , Regulación de la Expresión Génica de las Plantas , Isopenteniladenosina/análogos & derivados , Isopenteniladenosina/metabolismo , Malus/genética , Malus/crecimiento & desarrollo , Reguladores del Crecimiento de las Plantas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , RNA-Seq
6.
Molecules ; 27(13)2022 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-35807421

RESUMEN

The ß-sheet is one of the common protein secondary structures, and the aberrant aggregation of ß-sheets is implicated in various neurodegenerative diseases. Cross-strand interactions are an important determinant of ß-sheet stability. Accordingly, both diagonal and lateral cross-strand interactions have been studied. Surprisingly, diagonal cross-strand ion-pairing interactions have yet to be investigated. Herein, we present a systematic study on the effects of charged amino acid side-chain length on a diagonal ion-pairing interaction between carboxylate- and ammonium-containing residues in a ß-hairpin. To this end, 2D-NMR was used to investigate the conformation of the peptides. The fraction folded population and the folding free energy were derived from the chemical shift data. The fraction folded population for these peptides with potential diagonal ion pairs was mostly lower compared to the corresponding peptide with a potential lateral ion pair. The diagonal ion-pairing interaction energy was derived using double mutant cycle analysis. The Asp2-Dab9 (Asp: one methylene; Dab: two methylenes) interaction was the most stabilizing (-0.79 ± 0.14 kcal/mol), most likely representing an optimal balance between the entropic penalty to enable the ion-pairing interaction and the number of side-chain conformations that can accommodate the interaction. These results should be useful for designing ß-sheet containing molecular entities for various applications.


Asunto(s)
Aminoácidos , Compuestos de Amonio , Aminoácidos/química , Ácidos Carboxílicos , Modelos Moleculares , Péptidos/química , Pliegue de Proteína , Estructura Secundaria de Proteína , Proteínas , Termodinámica
7.
BMC Med ; 19(1): 239, 2021 10 07.
Artículo en Inglés | MEDLINE | ID: mdl-34615542

RESUMEN

BACKGROUND: With the revolutionary progress of immune checkpoint inhibitors (ICIs) achieved in non-small cell lung cancers (NSCLC), identifying patients benefiting from ICIs becomes critical and urgent. The associations of genomic alterations in protein tyrosine phosphatase receptor-type (PTPRs) and ICIs responses are unknown. METHODS: Whole-exome sequencing (WES) of 73 advanced NSCLC tumors sampled before anti-PD-(L)1 therapy was carried out with corresponding clinical data collected as a discovery cohort to find the associations of PTPR mutations and ICI responses. Three validation cohorts consolidated by 7 public cohorts of 1920 NSCLC patients with WES or target sequencing data of tumor tissue-derived DNA or circulating tumor DNA (ctDNA) and relevant clinical data were applied as validation cohorts. The lung adenocarcinoma (LUAD) cohort (n=586) in The Cancer Genome Atlas (TCGA) database was used for analyzing the potential anti-tumor immunologic mechanisms. RESULTS: With the highest mutation frequency among all PTPRs, PTPRD mutations in non-squamous NSCLC (ns-NSCLC) were linked to longer progression-free survivals (PFS, 324 vs 63 days, hazard ratio (HR)=0.36, p= 0.0152) and higher objective response rate (ORR, p=0.0099). In validation cohort 1 (n=377), ns-NSCLC patients with tissue PTPRD mutations had favorable PFS (9.10 vs 4.33 months, HR=0.62, p=0.0184) and ORR (p=0.013). In validation cohort 2 (n=406), ns-NSCLC patients with tissue PTPRD mutations had favorable overall survivals (OS, over 40 vs 11.94 months, HR=0.57, p=0.011). In validation cohort 3 (n=1137), ns-NSCLC patients with ctDNA PTPRD mutations had longer PFS (6.97 vs 2.73 months, HR=0.63, p=0.028) and higher ORR (p=0.047). Moreover, it was deleterious mutations in phosphatase domains (phosphatase-mut), rather than other mutations (other-mut), that were responsible of PTPRD's prediction efficiency. In addition, in validation cohort 3, ctDNA phosphatase-mut also functioned as a predictive biomarker helping identify patients benefiting more from ICIs than chemotherapy (interaction P for PFS=0.0506, for OS=0.04). Univariate and multivariate regression analysis revealed that phosphatase-mut was independent on PD-L1 expression and tumor mutation burden (TMB) to predict. In silico analysis based on TCGA LUAD cohort discovered enhanced anti-tumor immunity in phosphatase-mut patients. CONCLUSIONS: Tissue or ctDNA PTPRD phosphatase domain deleterious mutations might function as a both prognostic and predictive biomarker predicting clinical outcomes of ICIs in ns-NSCLC patients, independent on TMB or PD-L1 expression.


Asunto(s)
ADN Tumoral Circulante , Neoplasias Pulmonares , Biomarcadores de Tumor/genética , Humanos , Inhibidores de Puntos de Control Inmunológico , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Mutación , Monoéster Fosfórico Hidrolasas/uso terapéutico , Pronóstico , Proteínas Tirosina Fosfatasas Clase 2 Similares a Receptores
8.
Org Biomol Chem ; 19(8): 1860-1866, 2021 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-33565556

RESUMEN

Collagen is a major structural component of the extracellular matrix and connective tissue. The key structural feature of collagen is the collagen triple helix, with a Xaa-Yaa-Gly (glycine) repeating pattern. The most frequently occurring triplet is Pro (proline)-Hyp (hydroxyproline)-Gly. The reversible thermal folding and unfolding of a series of heterotrimeric collagen triple helices with varying number of Pro-Hyp-Gly triplets were monitored by circular dichroism spectroscopy to determine the unfolding thermodynamic parameters Tm (midpoint transition temperature), ΔHTm (unfolding enthalpy), and ΔGunfold (unfolding free energy). The Tm and ΔGunfold of the heterotrimeric collagen triple helices increased with increasing number of Pro-Hyp-Gly triplets. The ΔGunfold increased by 2.0 ± 0.2 kcal mol-1 upon inserting one Pro-Hyp-Gly triplet into all three chains. The Tm difference between the most stable ABC combination and the second most stable BCC combination decreased with increasing number of Pro-Hyp-Gly triplets, even though the ΔGunfold difference remained the same. These results should be useful for tuning the stability of collagen triple helical peptides for hydrogel formation, recognition of denatured collagen triple helices as diagnostics and therapeutics, and targeted drug delivery.


Asunto(s)
Colágeno/metabolismo , Secuencia de Aminoácidos , Colágeno/síntesis química , Transición de Fase , Conformación Proteica en Hélice alfa , Estabilidad Proteica , Estructura Cuaternaria de Proteína , Desplegamiento Proteico , Termodinámica , Temperatura de Transición
9.
J Pept Sci ; 27(9): e3333, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34114290

RESUMEN

Interactions between charged amino acids significantly influence the structure and function of proteins. The encoded charged amino acids Asp, Glu, Arg, and Lys have different number of hydrophobic methylenes linking the backbone to the charged functionality. It remains to be fully understood how does this difference in the number of methylenes affect protein structure stability. Protein secondary structures are the fundamental three-dimensional building blocks of protein structures. ß-Sheet structures are particularly interesting, because these structures have been associated with a number of protein misfolding diseases. Herein, we report the effect of charged amino acid side chain length at two ß-strand positions individually on the stability of a ß-hairpin. The charged amino acids include side chains with a carboxylate, an ammonium, or a guanidinium group. The experimental peptides, fully folded reference peptides, and fully unfolded reference peptides were synthesized by solid phase peptide synthesis and analyzed by 2D NMR methods including TOCSY, DQF-COSY, and ROESY. Sequence specific assignments were performed for all peptides. The chemical shift data were used to derive the fraction folded population and the folding free energy for the experimental peptides. Results showed that the fraction folded population increased with increasing charged amino acid side chain length. These results should be useful for developing functional peptides that adopt the ß-conformation.


Asunto(s)
Aminoácidos , Péptidos , Conformación Proteica en Lámina beta , Pliegue de Proteína , Estructura Secundaria de Proteína , Termodinámica
10.
BMC Nephrol ; 21(1): 316, 2020 07 31.
Artículo en Inglés | MEDLINE | ID: mdl-32736534

RESUMEN

BACKGROUND: It is controversial for the effect and safety between cinacalcet and other treatments in treating secondary hyperparathyroidism for patients with chronic kidney disease (CKD) or end-stage renal disease (ESRD). METHODS: Embase, PubMed, and Cochrane Library were searched through Feb 2017. 21 randomized controlled trials were included. We calculated the pooled mean difference (MD), relative risk (RR) and corresponding 95% confidence interval (CI). RESULT: Patients received calcimimetic agents had significantly decreased serum parathyroid hormone (MD = - 259.24 pg/mL, 95% CI: - 336.23 to - 182.25), calcium (MD = - 0.92 mg/dL, 95% CI: - 0.98 to - 0.85) and calcium phosphorus product (MD = - 5.97 mg2/dL2, 95% CI: - 9.77 to - 2.16) concentration compared with control treatment. However, the differences in cardiovascular mortality and all-cause mortality between calcimimetics agents and control group were not statistically significant. The incidence of nausea (RR = 2.13, 95% CI: 1.62 to 2.79), vomiting (RR = 1.99, 95% CI: 1.78 to 2.23) and hypocalcemia (RR = 10.10, 95% CI: 7.60 to 13.43) in CKD patients with calcimimetics agents was significantly higher than that with control treatment. CONCLUSION: Cinacalcet improved the biochemical parameters in CKD patients, but did not improve all-cause mortality and cardiovascular mortality. Moreover, cinacalcet can cause some adverse events.


Asunto(s)
Hormonas y Agentes Reguladores de Calcio/uso terapéutico , Cinacalcet/uso terapéutico , Hiperparatiroidismo Secundario/tratamiento farmacológico , Fallo Renal Crónico/complicaciones , Humanos , Hiperparatiroidismo Secundario/etiología , Ensayos Clínicos Controlados Aleatorios como Asunto , Insuficiencia Renal Crónica/complicaciones
11.
Chembiochem ; 20(7): 931-939, 2019 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-30537200

RESUMEN

The RNA recognition motif (RRM), which is the most abundant RNA-binding motif in eukaryotes, is a well-structured domain of about 90 amino acids, yet the ß2ß3 hairpin, corresponding to strands 2 and 3 of the ß-sheet, and the intervening loop make essential interactions with RNA in many RRM complexes. A series of small cyclic peptide mimics of the ß2ß3 hairpin of Rbfox2 protein that recognize the terminal loop of precursor miR-20b have been designed to investigate whether the full RNA-binding protein can be mimicked with a minimal structurally preorganized peptide. Within a small library of seven cyclic peptides, a peptide with low-micromolar affinity for the miR-20b precursor was found. NMR spectroscopy titration data suggest that this peptide specifically targets the apical loop of pre-miR-20b. This work shows that it is possible to mimic RNA-binding proteins with designed stable peptides, which provide a starting point for designing or evolving small peptide mimetics of RRM proteins.


Asunto(s)
MicroARNs/metabolismo , Péptidos Cíclicos/metabolismo , Peptidomiméticos/metabolismo , Factores de Empalme de ARN/química , Proteínas Represoras/química , Secuencia de Aminoácidos , Humanos , Péptidos Cíclicos/química , Peptidomiméticos/química , Prueba de Estudio Conceptual , Unión Proteica , Dominios Proteicos , Motivo de Reconocimiento de ARN
12.
Cell Physiol Biochem ; 42(2): 530-536, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28578340

RESUMEN

BACKGROUND/AIMS: Autophagy is an evolutionarily conserved mechanism that affects the survival and functions of vascular smooth muscle cells (VSMCs). We explored the role of microRNAs (miRNAs) in regulating autophagy in VSMCs exposed to high phosphorus (Pi) levels. METHODS: VSMCs were isolated from the thoracic aorta of rats and were cultured primarily. Real-time PCR was used to measure the mRNA expression of indicated genes. Western blotting was performed to detect the protein expression of autophagy-related markers. RESULTS: We found that treatment with high Pi levels (1 and 3 mM) activated LC3II expression and promoted autophagic flux in VSMCs. Conversely, treatment with an autophagy inhibitor decreased LC3II expression. Pi stimulation dysregulated the expression of several miRNAs such as miR-18a, miR-21, miR-23a, miR-30b, and miR-31a. However, miR-30b overexpression decreased Pi-induced expression of autophagy-related marker genes such as BECN1, ATG5, and LC3b, whereas miR-30b downregulation increased Pi-induced expression of these genes. In addition, we found that miR-30b directly targeted BECN1. CONCLUSIONS: These data suggest that miR-30b plays an important role in the regulation of high Pi level-induced autophagy in VSMCs by targeting BECN1.


Asunto(s)
Aorta Torácica/metabolismo , Autofagia/efectos de los fármacos , Beclina-1/genética , MicroARNs/genética , Proteínas Asociadas a Microtúbulos/biosíntesis , Animales , Aorta Torácica/efectos de los fármacos , Aorta Torácica/patología , Autofagia/genética , Beclina-1/biosíntesis , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , MicroARNs/biosíntesis , Proteínas Asociadas a Microtúbulos/genética , Músculo Liso Vascular/efectos de los fármacos , Músculo Liso Vascular/metabolismo , Fósforo/farmacología , Ratas
13.
Biophys J ; 110(9): 2026-33, 2016 05 10.
Artículo en Inglés | MEDLINE | ID: mdl-27166810

RESUMEN

Cholesterol, due to its condensing effect, is considered an important regulator of membrane thickness. Other sterols, due to their structural similarities to cholesterol, are often assumed to have a universal effect on membrane properties similar to the condensing effect of cholesterol, albeit possibly to different degrees. We used x-ray diffraction to investigate this assumption. By the combination of lamellar diffraction and grazing-angle scattering, we measured the membrane thickness and the tilt-angle distribution of the lipid's hydrocarbon chains. This method is sensitive to phase separation, which is important for examining the miscibility of sterols and phospholipids. Mixtures of ergosterol or cholesterol with dimyristoylphosphatidylcholine, palmitoyloleoylphosphatidylcholine, and dioleoylphosphatidylcholine were systematically studied. We found that mixing ergosterol with phospholipids into a single phase became increasingly difficult with higher sterol concentrations and also with higher concentrations of unsaturated lipid chains. The only condensing effect of ergosterol was found in dimyristoylphosphatidylcholine, although the effect was less than one-third of the effect of cholesterol. Unlike cholesterol, ergosterol could not maintain a fixed electron density profile of the surrounding lipids independent of hydration. In dioleoylphosphatidylcholine and palmitoyloleoylphosphatidylcholine, ergosterol made the membranes thinner, opposite to the effect of cholesterol. In all cases, the tilt-angle variation of the chain diffraction was consistent with the membrane thickness changes measured by lamellar diffraction, i.e., a thickening was always associated with a reduction of chain tilt angles. Our findings do not support the notion that different sterols have a universal behavior that differs only in degree.


Asunto(s)
Membrana Celular/química , Membrana Celular/efectos de los fármacos , Colesterol/farmacología , Ergosterol/farmacología , Fosfolípidos/química
14.
Am J Nephrol ; 41(1): 28-36, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25634106

RESUMEN

AIMS: Vascular calcification is a risk factor for causing cardiovascular events and has a high prevalence among chronic kidney disease (CKD) patients. However, the molecular mechanism underlying this pathogenic process is still obscure. METHODS: Vascular smooth muscle cells (VSMCs) were induced by a concentration of phosphorus (Pi) of 2.5 mM, and were subjected to cell calcification analyses. The effect of high Pi on the Wnt/ß-catenin pathway was measured using a TOP/FOP-Flash reporter assay. The transcriptional regulation of ß-catenin on PIT1 (a type III sodium-dependent phosphate cotransporter) was confirmed by promoter reporter and chromatin immunoprecipitation assays. The 5/6 nephrectomized rat was used as an in vivo model and was fed a high Pi diet to induce aortic calcification. Serum levels of phosphate, calcium, creatine, and blood urea nitrogen were measured, and abdominal aortic calcification was examined. RESULTS: High Pi induced VSMC calcification, downregulated expression levels of VSMC markers, and upregulated levels of osteogenic markers. High Pi activated the Wnt/ß-catenin pathway and ß-catenin activity. ß-Catenin was involved in the process of high Pi-induced VSMC calcification. Further investigation revealed that ß-catenin transcriptionally regulated Pit1, a necessary player in VSMC osteogenic phenotype change and calcification. The in vivo study showed that ß-catenin was involved in rat abdominal aortic calcification induced by high Pi. When knockdown expression of ß-catenin in the rat model was investigated, we found that aortic calcification was reduced. CONCLUSION: These results suggest that ß-catenin is an important player in high phosphorus level-induced aortic calcification in CKD.


Asunto(s)
Músculo Liso Vascular/metabolismo , Miocitos del Músculo Liso/metabolismo , Fósforo/farmacología , Insuficiencia Renal Crónica/metabolismo , Calcificación Vascular/metabolismo , Vía de Señalización Wnt , beta Catenina/metabolismo , Actinas/genética , Actinas/metabolismo , Animales , Aorta , Nitrógeno de la Urea Sanguínea , Calcio/sangre , Células Cultivadas , Subunidad alfa 1 del Factor de Unión al Sitio Principal/genética , Subunidad alfa 1 del Factor de Unión al Sitio Principal/metabolismo , Creatina/sangre , Modelos Animales de Enfermedad , Regulación de la Expresión Génica , Técnicas de Silenciamiento del Gen , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Masculino , Músculo Liso Vascular/efectos de los fármacos , Miocitos del Músculo Liso/efectos de los fármacos , Nefrectomía , Osteopontina/genética , Osteopontina/metabolismo , Fósforo Dietético/metabolismo , Plasmalógenos/sangre , Ratas , Ratas Sprague-Dawley , Proteínas Cotransportadoras de Sodio-Fosfato de Tipo III/genética , Proteínas Cotransportadoras de Sodio-Fosfato de Tipo III/metabolismo , Calcificación Vascular/etiología , beta Catenina/genética
15.
Langmuir ; 30(13): 3832-44, 2014 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-24621316

RESUMEN

Self-assembled monolayers (SAMs) from an 11-cyanoundecyltrichlorosilane (CN-SAM) precursor were deposited on porous SiCOH low-k dielectrics with three different pore radii, namely, 1.7, 0.7, and lower than 0.5 nm. The low-k dielectrics were first pretreated with either O2 or He/H2 plasma in order to generate silanol groups on the hydrophobic pristine surface. Subsequently, the SAMs were chemically grafted to the silanol groups on the low-k surface. The SAMs distribution in the low-k films depends on the pore diameter: if the pore diameter is smaller than the size of the SAMs precursors, the SAM molecules are confined to the surface, while if the pore diameter exceeds the van der Waals radius of the SAMs precursor, the SAMs molecules reach deeper in the dielectric. In the latter case, when the pore sidewalls are made hydrophilic by the plasma treatment, the chemical grafting of the SAM precursors follows the profile of the generated silanol groups. The modification depth induced by the O2 plasma is governed by the diffusion of the oxygen radicals into the pores, which makes it the preferred choice for microporous materials. On the other hand, the vacuum ultraviolet (VUV) light plays a critical role, which makes it more suitable for hydrolyzing mesoporous materials. In addition to the density of the surface -OH groups, the nanoscale concave curvature associated with the pores also affects the molecular packing density and ordering with respect to the self-assembly behavior on flat surfaces. A simple model which correlates the low-k pore structure with the plasma hydrophilization mechanism and the SAMs distribution in the pores is presented.

16.
Pharmazie ; 69(12): 904-8, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25951664

RESUMEN

This study aimed to investigate the protective effect of metformin on renal injury of C57BL/6J mice treated with a high fat diet. High-fat diet for 12 weeks was used to establish the mice model of metabolism syndrome and the intervention of metformin (75 mg x kg(-1) x d(-1)) for 4 weeks, and plasma biochemical indicator and body weight were used to evaluate the model. Sterol regulatory element-binding protein (SERBP)-1c, TNF-α, NADPH Oxidase (NOX)4 mRNA was determined by real time-PCR. Phospho-AMP-activated protein kinase (P-AMPK)α protein was detected by western blotting. Oil Red O staining, Masson staining and HE staining were for observing renal pathological changes. At the end of 12th week, compared with mice on low fat diet (LFD), body weight (BW), the levels of fasting insulin (FINS), plasma and renal triglyceride (TG) were higher and plasma high density lipoprotein (HDL) and insulin sensitivity index (ISI) were significantly lower, but the levels of fasting blood glycemia (FBG), plasma total cholesterol (TC) and renal TC had no changes; Oil Red O staining revealed renal lipids deposition, Masson staining and HE staining revealed glomerular hypertrophy, matrix increasing, and inflammatory cells infiltration in glomerular; the expression of p-AMPKα protein decreased and the expression of SREBP-1c, TNF-α, NOX4 mRNA increased significantly in mouse treated with high fat diet (HFD). Compared with the HFD group, through metformin interventing, metabolic disorders were significantly improved, renal lipids deposition and other pathological changes were ameliorated, the expression of p-AMPKα protein increased and the expression of SREBP-1c, TNF-α, NOX4 mRNA decreased significantly. Metformin improved metabolic disorders, upregulated activity of renal AMPK, diminished the expression of renal SREBP-1c, TNF-α, NOX4 mRNA, decreased accumulation of renal lipids, and prevened renal injury.


Asunto(s)
Lesión Renal Aguda/inducido químicamente , Lesión Renal Aguda/prevención & control , Dieta Alta en Grasa/efectos adversos , Hipoglucemiantes/uso terapéutico , Metformina/uso terapéutico , Lesión Renal Aguda/patología , Animales , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Riñón/metabolismo , Riñón/patología , Metabolismo de los Lípidos/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Nefritis/patología , Nefritis/prevención & control , Estrés Oxidativo/efectos de los fármacos
17.
PLoS One ; 19(3): e0299956, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38457447

RESUMEN

Extreme precipitation usually cause grievous losses&casualties, which varies greatly under different scenarios. This paper took Henan province as an example, it innovatively constructed three different extreme precipitation scenarios and built indicators system of social vulnerability from exposure, sensitivity and resilience based on MOVE framework. Social Vulnerability Indexs(SoVI) were then calculated by mathematical models under three different reoccurrence intervals. The results show that SoVI was low in the west and high in the north. High SoVI areas expanded to the middle and south as recurrence intervals increased. SoVI in each area of Henan province increased along with the recurrence intervals at different growth rates. The larger the recurrence interval was, the faster the SoVI increased. The results indicate SoVI is greatly affected by disaster levels, which need to be incorporated into social vulnerability. This study provides not only a new thought for social vulnerability assessment, but also a reference for the policymakers to formulate related risk management policies.


Asunto(s)
Desastres , Vulnerabilidad Social , China , Medición de Riesgo , Gestión de Riesgos
18.
Front Endocrinol (Lausanne) ; 15: 1348771, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38863934

RESUMEN

Background: Ovarian stimulation (OS) for in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) in women with PCOS often results in multiple follicular development, yet some individuals experience poor or suboptimal responses. Limited data exist regarding the impact of poor/suboptimal ovarian response on pregnancy outcomes in women with PCOS. Objectives: The aim of this study was to evaluate whether the live birth rate (LBR) per fresh embryo transfer and cumulative live birth rate (CLBR) per aspiration cycle differ in women with PCOS defined by the Patient-Oriented Strategy Encompassing IndividualizeD Oocyte Number (POSEIDON) criteria. Methods: A retrospective study involving 2,377 women with PCOS who underwent their first IVF/ICSI cycle at Sun Yat-sen Memorial Hospital from January 2011 to December 2020 was used. Patients were categorized into four groups based on age, antral follicle count, and the number of oocytes retrieved, according to the POSEIDON criteria. The LBR and CLBR were compared among these groups. Logistic regression analysis was performed to assess whether the POSEIDON criteria served as independent risk factors and identify factors associated with POSEIDON. Results: For patients <35 years old, there was no significant difference in the clinical pregnancy rate between POSEIDON and non-POSEIDON patients, whereas POSEIDON patients exhibited lower rates of implantation and live birth. POSEIDON Group 1a displayed lower rates of implantation, clinical pregnancy, and live birth. However, no significant differences were observed in the rates of clinical pregnancy and live birth between POSEIDON Group 1b and non-POSEIDON groups. For patients ≥35 years old, there were no significant differences in the rates of implantation, clinical pregnancy, and live birth between POSEIDON and non-POSEIDON patients. CLBRs were significantly lower in POSEIDON Groups 1 and 2, compared with the non-POSEIDON groups. The levels of body mass index (BMI), follicle-stimulating hormone (FSH), and antral follicle count (AFC) were associated with POSEIDON hypo-response. POSEIDON was found to be associated with lower CLBR, but not LBR per fresh embryo transfer. Conclusions: In patients with PCOS, an unexpected suboptimal response can achieve a fair LBR per fresh embryo transfer. However, CLBR per aspirated cycle in POSEIDON patients was lower than that of normal responders. BMI, basal FSH level, and AFC were independent factors associated with POSEIDON. Our study provides data for decision-making in women with PCOS after an unexpected poor/suboptimal response to OS.


Asunto(s)
Tasa de Natalidad , Transferencia de Embrión , Fertilización In Vitro , Nacimiento Vivo , Inducción de la Ovulación , Síndrome del Ovario Poliquístico , Índice de Embarazo , Humanos , Femenino , Estudios Retrospectivos , Adulto , Embarazo , Transferencia de Embrión/métodos , Nacimiento Vivo/epidemiología , Fertilización In Vitro/métodos , Inyecciones de Esperma Intracitoplasmáticas/métodos , Resultado del Embarazo , Infertilidad Femenina/terapia
19.
ACS Sens ; 9(1): 483-493, 2024 01 26.
Artículo en Inglés | MEDLINE | ID: mdl-38206578

RESUMEN

Two-dimensional transition metal carbon/nitrides (MXenes) are promising candidates to revolutionize next-generation wearable sensors as high-performance surface-enhanced Raman scattering (SERS) substrates. However, low sensitivity of pure MXene nanosheets and weak binding force or uncontrolled in situ growth of plasmonic nanoparticles on hybrid MXene composites limit their progress toward universal and reliable sensors. Herein, we designed and manufactured a highly sensitive, structurally stable wearable SERS sensor by in situ fabrication of plasmonic nanostructures on the flexible TiVC membranes via the maximization of chemically reducing sites using alkaline treatment. DFT calculations and experimental characterization demonstrated that the hydroxyl functional groups on the surface of MXenes can facilitate the reduction of metal precursors and the nucleation of gold nanoparticles (AuNPs) and can be covalently attached to AuNPs. Thus, the fabricated flexible TiVC-OH-Au sensor satisfied the rigorous mechanical requirements for wearable sensors. In addition, combining the electromagnetic (EM) enhancement from dense AuNPs formed by the activation of nucleation sites and charge transfer (CT) between target molecule and substrate induced by the abundant DOS near the Fermi level of TiVC, the fabricated sensor exhibits ultrasensitivity, long-term stability, good signal repeatability, and excellent mechanical durability. Moreover, the proof-of-concept application of the wearable SERS sensor in sweat sensing was demonstrated to monitor the content of nicotine, methotrexate, nikethamide, and 6-acetylmorphine in sweat at the molecular level, which was an important step toward the universality and practicality of the wearable sensing technology.


Asunto(s)
Nanopartículas del Metal , Nitritos , Elementos de Transición , Dispositivos Electrónicos Vestibles , Oro/química , Nanopartículas del Metal/química , Monitoreo Fisiológico
20.
J Hazard Mater ; 469: 133893, 2024 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-38452684

RESUMEN

Sensitive and rapid identification of volatile organic compounds (VOCs) at ppm level with complex composition is vital in various fields ranging from respiratory diagnosis to environmental safety. Herein, we demonstrate a SERS gas sensor with size-selective and multiplexed identification capabilities for VOCs by executing the pre-enrichment strategy. In particular, the macro-mesoporous structure of graphene aerogel and micropores of metal-organic frameworks (MOFs) significantly improved the enrichment capacity (1.68 mmol/g for toluene) of various VOCs near the plasmonic hotspots. On the other hand, molecular MOFs-based filters with different pore sizes could be realized by adjusting the ligands to exclude undesired interfering molecules in various detection environments. Combining these merits, graphene/AuNPs@ZIF-8 aerogel gas sensor exhibited outstanding label-free sensitivity (up to 0.1 ppm toluene) and high stability (RSD=14.8%, after 45 days storage at room temperature for 10 cycles) and allowed simultaneous identification of multiple VOCs in a single SERS measurement with high accuracy (error < 7.2%). We visualize that this work will tackle the dilemma between sensitivity and detection efficiency of gas sensors and will inspire the design of next-generation SERS technology for selective and multiplexed detection of VOCs.

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