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1.
Proc Natl Acad Sci U S A ; 120(2): e2213528120, 2023 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-36595700

RESUMEN

Flow batteries are a promising energy storage solution. However, the footprint and capital cost need further reduction for flow batteries to be commercially viable. The flow cell, where electron exchange takes place, is a central component of flow batteries. Improving the volumetric power density of the flow cell (W/Lcell) can reduce the size and cost of flow batteries. While significant progress has been made on flow battery redox, electrode, and membrane materials to improve energy density and durability, conventional flow batteries based on the planar cell configuration exhibit a large cell size with multiple bulky accessories such as flow distributors, resulting in low volumetric power density. Here, we introduce a submillimeter bundled microtubular (SBMT) flow battery cell configuration that significantly improves volumetric power density by reducing the membrane-to-membrane distance by almost 100 times and eliminating the bulky flow distributors completely. Using zinc-iodide chemistry as a demonstration, our SBMT cell shows peak charge and discharge power densities of 1,322 W/Lcell and 306.1 W/Lcell, respectively, compared with average charge and discharge power densities of <60 W/Lcell and 45 W/Lcell, respectively, of conventional planar flow battery cells. The battery cycled for more than 220 h corresponding to >2,500 cycles at off-peak conditions. Furthermore, the SBMT cell has been demonstrated to be compatible with zinc-bromide, quinone-bromide, and all-vanadium chemistries. The SBMT flow cell represents a device-level innovation to enhance the volumetric power of flow batteries and potentially reduce the size and cost of the cells and the entire flow battery.


Asunto(s)
Líquidos Corporales , Bromuros , Tamaño de la Célula , Fibras de la Dieta , Zinc
2.
Diabetes Obes Metab ; 26(7): 2860-2868, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38646838

RESUMEN

AIM: To investigate the metabolism and disposition characteristics of HSK7653 in healthy male Chinese participants. METHODS: A single oral dose of 80 µCi (25 mg) [14C]HSK7653 capsules was administered to six healthy participants, and blood, plasma, urine and faeces were collected. Quantitative and qualitative analysis was conducted to investigate the pharmacokinetics, blood-to-plasma ratio, mass balance and metabolism of HSK7653. RESULTS: The drug was well absorbed and reached a maximum concentration at 1.25 h. The drug-related components (HSK7653 and its metabolites) were eliminated slowly, with a half-life (t1/2) of 111 h. Unchanged HSK7653 contributed to more than 97% of the total radioactivity in all plasma samples. The blood-to-plasma ratio (0.573-0.845) indicated that HSK7653 did not tend to distribute into blood cells. At 504 h postdose, up to 95.9% of the dose was excreted, including 79.8% in urine and 16.1% in faeces. Most of the radioactivity (75.5% dose) in excreta was unchanged HSK7653. In addition, nine metabolites were detected in urine and faeces. The most abundant metabolite was M6-2, a dioxidation product of HSK7653, which accounted for 4.73% and 2.63% of the dose in urine and faeces, respectively. The main metabolic pathways of HSK7653 in vivo included oxidation, pyrrole ring opening and sulphonamide hydrolysation. CONCLUSION: HSK7653 was well absorbed, slightly metabolized and slowly excreted in humans. The high plasma exposure and long t1/2 of HSK7653 may contribute to its long-lasting efficacy as a long-acting dipeptidyl peptidase-4 inhibitor.


Asunto(s)
Diabetes Mellitus Tipo 2 , Inhibidores de la Dipeptidil-Peptidasa IV , Humanos , Masculino , Inhibidores de la Dipeptidil-Peptidasa IV/farmacocinética , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Adulto , Biotransformación , Semivida , Heces/química , Adulto Joven , Voluntarios Sanos , Hipoglucemiantes/farmacocinética , Hipoglucemiantes/uso terapéutico , Administración Oral
3.
J Bone Miner Metab ; 42(2): 242-252, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38498197

RESUMEN

INTRODUCTION: This study was to investigate the correlations between pyrethroid exposure and bone mineral density (BMD) and osteopenia. MATERIALS AND METHODS: This cross-sectional study included 1389 participants over 50 years of age drawn from the 2007-2010 and 2013-2014 National Health and Nutrition Examination Survey (NHANES). Three pyrethroid metabolites, 3-phenoxybenzoic acid (3-PBA), trans-3-(2,2-dichlorovinyl)-2,2-dimethyl-cyclopropane-1-carboxylic acid (trans-DCCA), and 4-fluoro-3-phenoxybenzoic acid (4-F-3PBA) were used as indicators of pyrethroid exposure. Low BMD was defined as T-score < - 1.0, including osteopenia. Weighted multivariable linear regression analysis or logistic regression analysis was utilized to evaluate the correlation between pyrethroid exposure and BMD and low BMD. Bayesian kernel machine regression (BKMR) model was utilized to analyze the correlation between pyrethroids mixed exposure and low BMD. RESULTS: There were 648 (48.41%) patients with low BMD. In individual pyrethroid metabolite analysis, both tertile 2 and tertile 3 of trans-DCCA were negatively related to total femur, femur neck, and total spine BMD [coefficient (ß) = - 0.041 to - 0.028; all P < 0.05]. Both tertile 2 and tertile 3 of 4-F-3PBA were negatively related to total femur BMD (P < 0.05). Only tertile 2 [odds ratio (OR) = 1.63; 95% CI = 1.07, 2.48] and tertile 3 (OR = 1.65; 95% CI = 1.10, 2.50) of trans-DCCA was correlated with an increased risk of low BMD. The BKMR analysis indicated that there was a positive tendency between mixed pyrethroids exposure and low BMD. CONCLUSION: In conclusion, pyrethroids exposure was negatively correlated with BMD levels, and the associations of pyrethroids with BMD and low BMD varied by specific pyrethroids, pyrethroid concentrations, and bone sites.


Asunto(s)
Benzoatos , Enfermedades Óseas Metabólicas , Insecticidas , Éteres Fenílicos , Piretrinas , Adulto , Humanos , Persona de Mediana Edad , Piretrinas/efectos adversos , Piretrinas/análisis , Piretrinas/metabolismo , Insecticidas/efectos adversos , Insecticidas/análisis , Insecticidas/metabolismo , Encuestas Nutricionales , Estudios Transversales , Densidad Ósea , Teorema de Bayes , Exposición a Riesgos Ambientales/efectos adversos , Enfermedades Óseas Metabólicas/inducido químicamente , Enfermedades Óseas Metabólicas/epidemiología
4.
Lasers Surg Med ; 56(4): 382-391, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38570914

RESUMEN

BACKGROUND AND OBJECTIVES: Femtosecond laser trabeculotomy (FLT) creates aqueous humor outflow channels through the trabecular meshwork (TM) and is an emerging noninvasive treatment for open-angle glaucoma. The purpose of this study is to investigate the effect of pulse energy on outflow channel creation during FLT. MATERIALS AND METHODS: An FLT laser (ViaLase Inc.) was used to create outflow channels through the TM (500 µm wide by 200 µm high) in human cadaver eyes using pulse energies of 10, 15, and 20 µJ. Following treatment, tissues were fixed in 4% paraformaldehyde. The channels were imaged using optical coherence tomography (OCT) and assessed as full thickness, partial thickness, or not observable. RESULTS: Pulse energies of 15 and 20 µJ had a 100% success rate in creating full-thickness FLT channels as imaged by OCT. A pulse energy of 10 µJ resulted in no channels (n = 6), a partial-thickness channel (n = 2), and a full-thickness FLT channel (n = 2). There was a statistically significant difference in cutting widths between the 10 and 15 µJ groups (p < 0.0001), as well as between the 10 and 20 µJ groups (p < 0.0001). However, there was no statistically significant difference between the 15 and 20 µJ groups (p = 0.416). CONCLUSIONS: Fifteen microjoules is an adequate pulse energy to reliably create aqueous humor outflow channels during FLT in human cadaver eyes. OCT is a valuable tool when evaluating FLT.


Asunto(s)
Glaucoma de Ángulo Abierto , Trabeculectomía , Humanos , Trabeculectomía/métodos , Glaucoma de Ángulo Abierto/cirugía , Presión Intraocular , Rayos Láser , Cadáver
5.
Proc Natl Acad Sci U S A ; 118(37)2021 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-34493655

RESUMEN

Polymers of intrinsic microporosity (PIMs) have been used as precursors for the fabrication of porous carbon molecular sieve (CMS) membranes. PIM-1, a prototypical PIM material, uses a fused-ring structure to increase chain rigidity between spirobisindane repeat units. These two factors inhibit effective chain packing, thus resulting in high free volume within the membrane. However, a decrease of pore size and porosity was observed after pyrolytic conversion of PIM-1 to CMS membranes, attributed to the destruction of the spirocenter, which results in the "flattening" of the polymer backbone and graphite-like stacking of carbonaceous strands. Here, a spirobifluorene-based polymer of intrinsic microporosity (PIM-SBF) was synthesized and used to fabricate CMS membranes that showed significant increases in p-xylene permeability (approximately four times), with little loss in p-xylene/o-xylene selectivity (13.4 versus 14.7) for equimolar xylene vapor separations when compared to PIM-1-derived CMS membranes. This work suggests that it is feasible to fabricate such highly microporous CMS membranes with performances that exceed current state-of-the-art zeolites at high xylene loadings.

6.
Osteoporos Int ; 34(12): 2013-2025, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37695339

RESUMEN

This meta-analysis aims to evaluate the impact of Sodium Glucose Transporter 2 (SGLT2) inhibitors on fractures, bone mineral density (BMD), and bone metabolism markers in type 2 diabetes mellitus (T2DM) patients. Pooled relative risk (RR) with 95% confidence interval (CI) assessed the relationship between SGLT2 inhibitors and fracture risk. Weighted mean difference (WMD) with 95% CI explored the correlation between SGLT2 inhibitors and BMD, as well as bone metabolism markers. A total of 20 randomised controlled trials (RCTs) involving 12,764 patients were analysed. No significant association emerged between SGLT2 inhibitor use and elevated fracture risk (pooled RR = 1.21, 95% CI [0.95, 1.54], I2 = 22%). Furthermore, SGLT2 inhibitors exhibited no substantial effects on BMD changes at the lumbar spine (WMD = -0.02, 95% CI [-0.38, 0.34]), femoral neck (WMD = 0.11, 95% CI [-0.28, 0.50]), total hip (WMD = -0.20, 95% CI [-0.41, 0.01]), and distal forearm (WMD = -0.20, 95% CI [-0.62, 0.22]). Similarly, no notable impact of SGLT2 inhibitors on bone metabolism markers, including CTX (WMD = 0.04, 95% CI [-0.02, 0.09]), P1NP (WMD = 1.06, 95% CI [-0.44, 2.57]), PTH (WMD = 0.34, 95% CI [-0.07, 0.75]), calcium (WMD = 0.01, 95% CI [-0.02, 0.04]), and phosphate (WMD = 2.37, 95% CI [-0.76, 5.49]). The findings suggest that the utilization of SGLT2 inhibitors is not significantly linked to an elevated risk of fractures in individuals with T2DM. However, further clinical investigations and extended follow-up periods are warranted to establish more conclusive determinations.


Asunto(s)
Diabetes Mellitus Tipo 2 , Fracturas Óseas , Inhibidores del Cotransportador de Sodio-Glucosa 2 , Humanos , Inhibidores del Cotransportador de Sodio-Glucosa 2/efectos adversos , Densidad Ósea , Fracturas Óseas/etiología , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Riesgo , Ensayos Clínicos Controlados Aleatorios como Asunto
7.
Clin Oral Investig ; 27(10): 6111-6123, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37615776

RESUMEN

OBJECTIVES: The current research on single-nucleotide polymorphism (SNP) mutation sites at different positions of the FAM83H gene and their phenotypic changes leading to amelogenesis imperfecta (AI) is inconsistent. We identified a previously reported heterozygous nonsense mutation c.1192C>T (p.Q398*) in the FAM83H gene and conducted a comprehensive analysis of the dental ultrastructure and chemical composition changes induced by this mutation. Additionally, we predicted the protein feature affected by this mutation site. The aim was to further deepen our understanding of the diversity of AI caused by different mutation sites in the FAM83H gene. METHODS: Whole-exome sequencing (WES) and Sanger sequencing were used to confirm the mutation sites. Physical features of the patient's teeth were investigated using various methods including cone beam computer tomography (CBCT), scanning electron microscopy (SEM), contact profilometry (roughness measurement), and a nanomechanical tester (nanoindentation measurement). The protein features of wild-type and mutant FAM83H were predicted using bioinformatics methods. RESULTS: One previously discovered FAM83H heterozygous nonsense mutation c.1192C>T (p.Q398*) was detected in the patient. SEM revealed inconsistent dentinal tubules, and EDS showed that calcium and phosphorus were lower in the patient's dentin but higher in the enamel compared to the control tooth. Roughness measurements showed that AI patients' teeth had rougher occlusal surfaces than those of the control tooth. Nanoindentation measurements showed that the enamel and dentin hardness values of the AI patients' teeth were both significantly reduced compared to those of the control tooth. Compared to the wild-type FAM83H protein, the mutant FAM83H protein shows alterations in stability, hydrophobicity, secondary structure, and tertiary structure. These changes could underlie functional differences and AI phenotype variations caused by this mutation site. CONCLUSIONS: This study expands the understanding of the effects of FAM83H mutations on tooth structure. CLINICAL RELEVANCE: Our study enhances our understanding of the genetic basis of AI and may contribute to improved diagnostics and personalized treatment strategies for patients with FAM83H-related AI.


Asunto(s)
Amelogénesis Imperfecta , Humanos , Amelogénesis Imperfecta/genética , Codón sin Sentido/genética , Codón sin Sentido/análisis , Esmalte Dental/química , Proteínas/análisis , Proteínas/genética , Mutación
8.
Langmuir ; 38(45): 13753-13762, 2022 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-36331054

RESUMEN

It is very important to build uniform large-area dense hotspots to improve the surface-enhanced Raman scattering (SERS) detection limit. In our research, we designed and prepared a new flexibile SERS substrate with ultradense hot spots that has the advantages of high sensitivity, good repeatability, easy fabrication, and low cost. Due to the special dense hot spot structure, the substrate reaches a SERS enhancement factor of 2.1 × 1011. Because of the excellent physical stability of polydimethylsiloxane, the substrate can be bent at will, and the SERS performance will not change with bending. This is very important to extract effective detection objects on complex surfaces. The substrate has good light transmittance and softness and can be directly attached to the detected agricultural products to realize real-time and rapid SERS monitoring. This structure exhibits extraordinary performance for thiram detection in the ultralow concentration range of 10-13 M.


Asunto(s)
Nanopartículas del Metal , Tiram , Plata/química , Dióxido de Silicio , Nanopartículas del Metal/química , Espectrometría Raman
9.
Adv Exp Med Biol ; 1370: 161-169, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35882792

RESUMEN

The purpose of this study was to investigate the effects of taurine on blood indices of broilers with chronic heat stress and to provide theoretical basis for the application of taurine in the anti-chronic heat stress of broilers. In the test, 240 AA + broilers at 7 days of age were randomly divided into five groups: the normal temperature control group (24 ± 2 °C) in group C, the heat stress control group (34 ± 2 °C) in HS group, and the LTau, MTau, and HTau groups in heat under stress conditions, 0.5 g/L, 2 g/L, and 8 g/L taurine, were added to the drinking water, and each group was repeated three times. After 2 weeks of feeding at normal temperature, heat stress began. The test period was 4 weeks. Blood was collected at 6 h, 12 h, 7 d, 14 d, 21 d, and 28 d after heat stress, and serum was separated. The results showed that compared with the HS group, MTau significantly increased the total serum protein content (P < 0.05), but the other groups were not significantly different (P > 0.05). The MTau and HTau groups contained significantly lowered serum uric acid levels than the HS group (P < 0.05). At 7d and 14d, the LTau, MTau, and HTau groups all exhibited significantly increased T3 and T4 concentrations (P < 0.05). There was no significant difference between the groups at other times (P > 0.05). Compared with the HS group, the MTau group contained significantly reduced serum CK activity, LDH activity, AST activity, and ALT activity (P < 0.05). Compared with the LTau, MTau, and HTau groups, serum MDA content was significantly increased in the heat-stressed broilers (P < 0.05). MTau group contained significantly increased T-AOC, SOD, CAT, and GSH-PX levels (P < 0.05). The other groups were not significantly different (P > 0.05). Compared with group C, serum HSP60 and HSP70 levels were significantly elevated in the HS group (P < 0.05). Compared with the HS group, the LTau and MTau groups contained significantly increased serum HSP60 and HSP70 concentrations (P < 0.05), but the other groups were not significantly different (P > 0.05). In conclusion, taurine can alleviate the symptoms of chronic heat stress of broilers, regulate the metabolism of the body, and improve the antioxidant activity of the body.


Asunto(s)
Antioxidantes , Taurina , Animales , Antioxidantes/metabolismo , Antioxidantes/farmacología , Pollos/fisiología , Suplementos Dietéticos , Proteínas HSP70 de Choque Térmico , Respuesta al Choque Térmico , Calor , Taurina/farmacología , Ácido Úrico
10.
Adv Exp Med Biol ; 1370: 153-160, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35882791

RESUMEN

The aim of this study was to investigate the effects of taurine on tissue injury, protein metabolism, and basal metabolism of broilers after chronic heat stress by detecting serum physiological and biochemical indices. In the test, 240 AA + broilers at 7 days of age were randomly divided into five groups: the normal temperature control group (24 ± 2 °C) in group C, the heat stress control group (34 ± 2 °C) in HS group, and the LTau, MTau, and HTau groups in heat under stress conditions, 0.5, 2, and 8 g/L taurine were added to the drinking water, and each group was repeated three times. After 2 weeks of feeding at normal temperature, heat stress began. The test period was 4 weeks. Blood was collected at 6 h, 12 h, 7 d, 14 d, 21 d, and 28 d after heat stress, and serum was separated. The results showed that compared with the HS group, the MTau group had significantly higher total serum protein content (P < 0.05), while the other groups were not significantly different (P > 0.05). The MTau and HTau groups had significantly lower serum uric acid levels than the HS group (P < 0.05). At 7d and 14d, the LTau, MTau, and HTau groups all showed significantly increased T3 and T4 concentrations (P < 0.05). There was no significant difference between the groups thereafter (P > 0.05). Compared with HS group, the MTau group contained significantly reduced serum CK activity, LDH activity, AST activity, and ALT activity (P < 0.05). In conclusion, the effects of taurine on tissue damage, protein metabolism, and basal metabolism of broilers after chronic heat stress were studied by measuring serum physiological and biochemical indices. To provide a theoretical basis for the application of taurine in acute heat-stressed broilers.


Asunto(s)
Pollos , Taurina , Animales , Pollos/fisiología , Dieta , Suplementos Dietéticos , Respuesta al Choque Térmico , Calor , Taurina/farmacología , Ácido Úrico
11.
Biochem Biophys Res Commun ; 528(2): 243-248, 2020 07 23.
Artículo en Inglés | MEDLINE | ID: mdl-32482388

RESUMEN

Previous studies reported that ginsenoside Rg1 (Rg1) exerts antidepressant-like effect in animal models of depression. However, its effect on post-traumatic stress disorder (PTSD) remains elusive; PTSD is a common and costly psychiatric condition with negative cognitive and affective dysfunctions, such as anxiety and depression. In this study, we evaluated the role of Rg1 in a validated mice model of PTSD induced by single-prolonged stress (SPS). Sertraline, one of the FDA-approved medications for PTSD was used as a positive control. Our results showed that SPS exposure led to increased anxiety-like and despair-like behaviors. SPS exposure also caused enhanced contextual fear memory and overgeneralization of learned fear. Sertraline significantly ameliorated those abnormal behaviors induced by SPS, while Rg1 did not. Meanwhile, we found that sertraline but not Rg1 blocked the suppressive effect of SPS on adult neurogenesis in the hippocampus. Consistently, we found that SPS elevated adrenocorticotropic hormone (ACTH) level in the serum, which was inhibited by sertraline but not Rg1. Our results thus demonstrate that Rg1 at a dose used to treat depression may not be effective to rescue behavioral deficits associated with PTSD.


Asunto(s)
Ginsenósidos/uso terapéutico , Trastornos por Estrés Postraumático/tratamiento farmacológico , Trastornos por Estrés Postraumático/etiología , Estrés Psicológico/complicaciones , Estrés Psicológico/tratamiento farmacológico , Hormona Adrenocorticotrópica/sangre , Animales , Conducta Animal , Modelos Animales de Enfermedad , Ginsenósidos/farmacología , Hipocampo/efectos de los fármacos , Hipocampo/patología , Masculino , Ratones Endogámicos C57BL , Neurogénesis/efectos de los fármacos , Sertralina/farmacología , Sertralina/uso terapéutico , Trastornos por Estrés Postraumático/sangre , Estrés Psicológico/sangre
12.
Biochem Biophys Res Commun ; 529(4): 1131-1136, 2020 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-32819576

RESUMEN

The brain-gut hormone ghrelin and its receptor GHS-R1a, the growth hormone secretagogue receptor 1a, regulates diverse functions of central nervous system including stress response and mood. Both acute and chronic caloric restrictions (CR) were reported to increase endogenous ghrelin level meanwhile regulate anxiety-related behaviors; however, the causal relationship between CR-induced ghrelin elevation and anxiety are not fully established. Here, we introduced an acute (24 h) and a chronic (10wks) CR procedure to both GHS-R1a KO (Ghsr-/-) mice and WT (Ghsr+/+) littermates, and compared their anxiety-related behaviors. We found that acute CR induced anxiolytic and anti-despairing behaviors in Ghsr+/+ mice but not in Ghsr-/- mice. Ad-libitum refeeding abolished the effect of acute CR on anxiety-related behaviors. In contrast, chronic CR for 10wks facilitated despair-like behavior meanwhile inhibited anxiety-like behavior in Ghsr+/+ mice. GHS-R1a deficiency rescued despair-like behavior while did not affect anxiolytic response induced by chronic CR. In addition, we found elevated interleukin-6 (IL-6) in serum of Ghsr+/+ mice after chronic CR, but not in Ghsr-/- mice. Altogether, our findings indicated that acute CR and chronic CR have different impacts on anxiety-related behaviors, and the former is dependent on ghrelin/GHS-R1a signaling while the latter may not always be. In addition, our findings suggested that GHS-R1a-dependent elevation in serum IL-6 might contribute to increased despair-like behavior in chronic CR state.


Asunto(s)
Ansiedad/metabolismo , Conducta Animal , Restricción Calórica , Ghrelina/metabolismo , Receptores de Ghrelina/metabolismo , Transducción de Señal , Animales , Ansiolíticos/metabolismo , Ansiedad/sangre , Ghrelina/deficiencia , Interleucina-6/sangre , Masculino , Ratones Endogámicos C57BL , Receptores de Ghrelina/deficiencia
13.
J Memb Sci ; 5932020 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-32863548

RESUMEN

Self-diffusivities of ethane were measured by multinuclear pulsed field gradient (PFG) NMR inside zeolitic imidazolate framework-11 (ZIF-11) crystals dispersed in several selected polymers to form mixed-matrix membranes (MMMs). These diffusivities were compared with the corresponding intracrystalline self-diffusivities in ZIF-11 crystal beds. It was observed that the confinement of ZIF-11 crystals in ZIF-11 / Torlon MMM can lead to a decrease in the ethane intracrystalline self-diffusivity. Such diffusivity decrease was observed at different temperatures used in this work. PFG NMR measurements of the temperature dependence of the intracrystalline self-diffusivity of ethylene in the same ZIF-11 / Torlon MMM revealed similar diffusivity decrease as well as an increase in the diffusion activation energy in comparison to those in unconfined ZIF-11 crystals in a crystal bed. These observations for ethane and ethylene were attributed to the reduction of the flexibility of the ZIF-11 framework due to the confinement in Torlon leading to a smaller effective aperture size of ZIF-11 crystals. Surprisingly, the intra-ZIF diffusion selectivity for ethane and ethylene was not changed appreciably by the confinement of ZIF-11 crystals in Torlon in comparison to the selectivity in a bed of ZIF-11 crystals. No ZIF-11 confinement effects leading to a reduction in the intracrystalline self-diffusivity of ethane and ethylene were observed for the other two studied MMM systems: ZIF-11 / Matrimid and ZIF-11 / 6FDA-DAM. The absence of the confinement effect in the latter MMMs can be related to the lower values of the polymer bulk modulus in these MMMs in comparison to that in ZIF-11 / Torlon MMM. In addition, there may be a contribution from possible differences in the ZIF-11/polymer adhesion in different MMM types.

14.
Eur J Cancer Care (Engl) ; 29(5): e13260, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32489013

RESUMEN

OBJECTIVE: The aim of the study was to find factors associated with overall survival (OS) and establish a nomogram predicting OS of patients with gastric cancer (GC) after D2R0 resection. METHODS: Demographic and clinicopathologic factors of patients with GC underwent D2R0 surgical resection were retrospectively collected from medical records, telephone interview or outpatient follow-up. To find factors significantly associated with OS, univariate and multivariate analyses were conducted. The concordance index (C-index) was used to measure the accuracy of the nomogram. Discrimination and calibration of the nomogram were tested using the patients in the validation set. RESULTS: Overall, patients with 890 GC underwent D2R0 surgical resection were included. Based on the results of univariate analysis and multivariate analysis, T stage, number of metastatic local lymph nodes, lymph node positive rate, adjuvant chemotherapy and diameter of tumour were used to construct a nomogram predicting OS of patients with GC after surgical resection. In the validation cohort, the C-index was 0.73 and the nomogram performed well in predicting OS. CONCLUSION: The nomogram was able to accurately predict OS of patients with GC underwent curative surgery and performed well in internal validation, which would also be useful for the decision-making of doctors.


Asunto(s)
Nomogramas , Neoplasias Gástricas , Humanos , Estadificación de Neoplasias , Pronóstico , Estudios Retrospectivos , Neoplasias Gástricas/patología , Neoplasias Gástricas/cirugía
15.
Int J Health Plann Manage ; 35(1): 79-103, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31149758

RESUMEN

This study aims to examine the correlations between air pollution and dynamic stroke mortality, which is defined as the daily real-time number of deaths from stroke. Death data were obtained from daily medical records of 7230 incidents from the Center for Disease Control and Prevention in the Longquanyi District of China from 2016 to 2017. Air pollution data were obtained from environmental monitoring stations in the Longquanyi District. Time series analysis using generalized additive Poisson regression models was applied, and single-pollutant and two-pollutant adjusted models were utilized. Furthermore, categories based on gender, age, and meteorological factors were considered in the analysis. The results indicated that PM2.5, PM10, O3 , and CO had significant effects on dynamic stroke mortality, which were stronger for older people and during the cold season. This study helps hospital managers, patients, and governments seeking to prevent and control the effects of air pollution on the risks of stroke.


Asunto(s)
Contaminación del Aire/efectos adversos , Accidente Cerebrovascular/epidemiología , Factores de Edad , Anciano , Contaminación del Aire/estadística & datos numéricos , Monóxido de Carbono/efectos adversos , Monóxido de Carbono/análisis , China/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Ozono/efectos adversos , Ozono/análisis , Material Particulado/efectos adversos , Material Particulado/análisis , Distribución de Poisson , Factores de Riesgo , Estaciones del Año , Factores Sexuales , Accidente Cerebrovascular/etiología
16.
Arterioscler Thromb Vasc Biol ; 38(6): 1309-1320, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29622561

RESUMEN

OBJECTIVE: Recently, we have demonstrated that acute glucosamine-induced augmentation of protein O-linked ß-N-acetylglucosamine (O-GlcNAc) levels inhibits inflammation in isolated vascular smooth muscle cells and neointimal formation in a rat model of carotid injury by interfering with NF-κB (nuclear factor-κB) signaling. However, the specific molecular target for O-GlcNAcylation that is responsible for glucosamine-induced vascular protection remains unclear. In this study, we test the hypothesis that increased A20 (also known as TNFAIP3 [tumor necrosis factor α-induced protein 3]) O-GlcNAcylation is required for glucosamine-mediated inhibition of inflammation and vascular protection. APPROACH AND RESULTS: In cultured rat vascular smooth muscle cells, both glucosamine and the selective O-linked N-acetylglucosaminidase inhibitor thiamet G significantly increased A20 O-GlcNAcylation. Thiamet G treatment did not increase A20 protein expression but did significantly enhance binding to TAX1BP1 (Tax1-binding protein 1), a key regulatory protein for A20 activity. Adenovirus-mediated A20 overexpression further enhanced the effects of thiamet G on prevention of TNF-α (tumor necrosis factor-α)-induced IκB (inhibitor of κB) degradation, p65 phosphorylation, and increases in DNA-binding activity. A20 overexpression enhanced the inhibitory effects of thiamet G on TNF-α-induced proinflammatory cytokine expression and vascular smooth muscle cell migration and proliferation, whereas silencing endogenous A20 by transfection of specific A20 shRNA significantly attenuated these inhibitory effects. In balloon-injured rat carotid arteries, glucosamine treatment markedly inhibited neointimal formation and p65 activation compared with vehicle treatment. Adenoviral delivery of A20 shRNA to the injured arteries dramatically reduced balloon injury-induced A20 expression and inflammatory response compared with scramble shRNA and completely abolished the vascular protection of glucosamine. CONCLUSIONS: These results suggest that O-GlcNAcylation of A20 plays a key role in the negative regulation of NF-κB signaling cascades in TNF-α-treated vascular smooth muscle cells in culture and in acutely injured arteries, thus protecting against inflammation-induced vascular injury.


Asunto(s)
Antiinflamatorios/farmacología , Traumatismos de las Arterias Carótidas/prevención & control , Proteínas de Unión al ADN/metabolismo , Glucosamina/farmacología , Músculo Liso Vascular/efectos de los fármacos , Miocitos del Músculo Liso/efectos de los fármacos , FN-kappa B/metabolismo , Proteína 3 Inducida por el Factor de Necrosis Tumoral alfa/metabolismo , Acetilglucosamina/metabolismo , Animales , Antiinflamatorios/metabolismo , Traumatismos de las Arterias Carótidas/genética , Traumatismos de las Arterias Carótidas/metabolismo , Traumatismos de las Arterias Carótidas/patología , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Citocinas/metabolismo , Proteínas de Unión al ADN/genética , Modelos Animales de Enfermedad , Glucosamina/metabolismo , Glicosilación , Masculino , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patología , Miocitos del Músculo Liso/metabolismo , Miocitos del Músculo Liso/patología , Neointima , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacos , Proteína 3 Inducida por el Factor de Necrosis Tumoral alfa/genética
17.
Angew Chem Int Ed Engl ; 58(38): 13259-13265, 2019 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-31228217

RESUMEN

Carbon molecular sieve (CMS) membranes are candidates for the separation of organic molecules due to their stability, ability to be scaled at practical form factors, and the avoidance of expensive supports or complex multi-step fabrication processes. A critical challenge is the creation of "mid-range" (e.g., 5-9 Å) microstructures that allow for facile permeation of organic solvents and selection between similarly-sized guest molecules. Here, we create these microstructures via the pyrolysis of a microporous polymer (PIM-1) under low concentrations of hydrogen gas. The introduction of H2 inhibits aromatization of the decomposing polymer and ultimately results in the creation of a well-defined bimodal pore network that exhibits an ultramicropore size of 5.1 Å. The H2 assisted CMS dense membranes show a dramatic increase in p-xylene ideal permeability (≈15 times), with little loss in p-xylene/o-xylene selectivity (18.8 vs. 25.0) when compared to PIM-1 membranes pyrolyzed under a pure argon atmosphere. This approach is successfully extended to hollow fiber membranes operating in organic solvent reverse osmosis mode, highlighting the potential of this approach to be translated from the laboratory to the field.

18.
Angew Chem Int Ed Engl ; 58(9): 2638-2643, 2019 02 25.
Artículo en Inglés | MEDLINE | ID: mdl-30577090

RESUMEN

Porous organic cages (POCs) are individual soluble, porous molecules. When fabricated into mixed-matrix membranes (MMMs), the soluble POC molecules have the potential to exhibit intimate molecular-level mixing with the polymer matrix. POCs have only recently been incorporated into mixed matrix membrane materials, but this process has not yet resulted in significant improvements of membrane performance. Now, vertex-functionalized amorphous scrambled porous organic cages (ASPOCs) have been utilized as membrane performance enhancers and the amorphous ASPOC mixtures are observed to distribute throughout the matrix without any indication of particle formation or agglomeration, creating unique, molecularly mixed composite membranes. Overall, the molecularly mixed composite membrane provide significant increases in both membrane permeability and selectivity, offering new avenues for creation of membranes with unique properties in industrially relevant separations.

19.
Gut ; 67(9): 1614-1625, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29760169

RESUMEN

OBJECTIVE: The initial colonisation of the human microbiota and the impact of maternal health on neonatal microbiota at birth remain largely unknown. The aim of our study is to investigate the possible dysbiosis of maternal and neonatal microbiota associated with gestational diabetes mellitus (GDM) and to estimate the potential risks of the microbial shift to neonates. DESIGN: Pregnant women and neonates suffering from GDM were enrolled and 581 maternal (oral, intestinal and vaginal) and 248 neonatal (oral, pharyngeal, meconium and amniotic fluid) samples were collected. To avoid vaginal bacteria contaminations, the included neonates were predominantly delivered by C-section, with their samples collected within seconds of delivery. RESULTS: Numerous and diverse bacterial taxa were identified from the neonatal samples, and the samples from different neonatal body sites were grouped into distinct clusters. The microbiota of pregnant women and neonates was remarkably altered in GDM, with a strong correlation between certain discriminatory bacteria and the oral glucose tolerance test. Microbes varying by the same trend across the maternal and neonatal microbiota were observed, revealing the intergenerational concordance of microbial variation associated with GDM. Furthermore, lower evenness but more depletion of KEGG orthologues and higher abundance of some viruses (eg, herpesvirus and mastadenovirus) were observed in the meconium microbiota of neonates associated with GDM. CONCLUSION: GDM can alter the microbiota of both pregnant women and neonates at birth, which sheds light on another form of inheritance and highlights the importance of understanding the formation of early-life microbiome.


Asunto(s)
Diabetes Gestacional/diagnóstico , Diabetes Gestacional/metabolismo , Disbiosis/metabolismo , Microbiota , Adulto , Glucemia/metabolismo , Cesárea/métodos , Diabetes Gestacional/sangre , Disbiosis/complicaciones , Femenino , Prueba de Tolerancia a la Glucosa/métodos , Humanos , Recién Nacido , Embarazo
20.
Macromol Rapid Commun ; 39(13): e1800274, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29806243

RESUMEN

Current additive manufacturing methods have significant limitations in the classes of compatible polymers. Many polymers of significant technological interest cannot currently be 3D printed. Here, a generalizable method for 3D printing of viscous tenary polymer solutions (polymer/solvent/nonsolvent) is applied to both "intrinsically porous" (a polymer of intrinsic microporosity, PIM-1) and "intrinsically nonporous" (cellulose acetate) polymers. Successful ternary ink formulations require balancing of solution thermodynamics (phase separation), mass transfer (solvent evaporation), and rheology. As a demonstration, a microporous polymer (PIM-1) incompatible with current additive manufacturing technologies is 3D printed into a high-efficiency mass transfer contactor exhibiting hierarchical porosity ranging from sub-nanometer to millimeter pores. Short contactors (1.27 cm) can fully purify (<1 ppm) toluene vapor (1000 ppm) in N2 gas for 1.7 h, which is six times longer than PIM-1 in traditional structures, and more than 4000 times the residence time of gas in the contactor. This solution-based additive manufacturing approach greatly extends the range of 3D-printable materials.


Asunto(s)
Celulosa/análogos & derivados , Impresión Tridimensional , Celulosa/química , Porosidad , Termodinámica
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