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1.
Molecules ; 29(12)2024 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-38930821

RESUMEN

2,6-pyridine dicarboxylic acid (DPA) is an exceptional biomarker of notorious anthrax spores. Therefore, the rapid, sensitive, and selective quantitative detection of DPA is extremely significant and urgent. This paper reports a Zn(II) metal-organic framework with the formula of {[Zn6(NDA)6(DPBT)3] 2H2O·3DMF}n (MOF-1), which consists of 2,6-naphthalenedicarboxylic acid (2,6-NDA), 4,7-di(4-pyridyl)-2,1,3-benzothiadiazole (DPBT), and Zn(II) ions. Structural analysis indicated that MOF-1 is a three-dimensional (3D) network which crystallized in the monoclinic system with the C2/c space group, revealing high pH, solvent, and thermal stability. Luminescence sensing studies demonstrated that MOF-1 had the potential to be a highly selective, sensitive, and recyclable fluorescence sensor for the identification of DPA. Furthermore, fluorescent test paper was made to detect DPA promptly with color changes. The enhancement mechanism was established by the hydrogen-bonding interaction and photoinduced electron transfer transition between MOF-1 and DPA molecules.


Asunto(s)
Biomarcadores , Estructuras Metalorgánicas , Tiadiazoles , Zinc , Estructuras Metalorgánicas/química , Zinc/química , Zinc/análisis , Tiadiazoles/química , Carbunco/diagnóstico , Ácidos Picolínicos/química , Ácidos Picolínicos/análisis , Bacillus anthracis , Modelos Moleculares
2.
Analyst ; 148(19): 4820-4828, 2023 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-37606537

RESUMEN

Cervical cancer is a significant global health issue primarily caused by high-risk types of human papillomavirus (HPV). Recent studies have reported an association between Trichomonas vaginalis (T. vaginalis) infections and HPV infections, highlighting the importance of simultaneously detecting these pathogens for effective cervical cancer risk management. However, current methods for detecting both T. vaginalis and HPV are limited. In this study, we present a novel approach using a microfluidic-chip-based system with loop-mediated isothermal amplification (LAMP) for the rapid and parallel detection of T. vaginalis, HPV16, HPV18, and HPV52 in a reagent-efficient and user-friendly manner. Compared to conventional LAMP assays in tubes, our system exhibits enhanced sensitivity with values of 2.43 × 101, 3.00 × 102, 3.57 × 101, and 3.60 × 102 copies per reaction for T. vaginalis, HPV16, HPV18, and HPV52, respectively. Additionally, we validated the performance of our chip by testing 47 clinical samples, yielding results consistent with the diagnostic methods used by the hospital. Therefore, our system not only offers a promising solution for concurrent diagnosis of T. vaginalis and HPV infections, particularly in resource-limited areas, due to its cost-effectiveness, ease of use, and rapid and accurate detection performance, but can also contribute to future research on the co-infection of these two pathogens. Moreover, the system possesses the capability to simultaneously detect up to 22 different types of pathogens, making it applicable across a wide range of domains such as diagnostics, food safety, and water monitoring.


Asunto(s)
Infecciones por Papillomavirus , Trichomonas vaginalis , Neoplasias del Cuello Uterino , Femenino , Humanos , Trichomonas vaginalis/genética , Virus del Papiloma Humano , Infecciones por Papillomavirus/diagnóstico , Neoplasias del Cuello Uterino/diagnóstico , Microfluídica , Sensibilidad y Especificidad , Técnicas de Amplificación de Ácido Nucleico/métodos , Papillomavirus Humano 16 , Papillomavirus Humano 18/genética
3.
Angew Chem Int Ed Engl ; 61(36): e202208281, 2022 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-35821569

RESUMEN

We have determined the complex atomic structure of high-temperature α-Ag9 GaTe6 phase with a hexagonal lattice (P63 mc space group, a=b=8.2766 Å, c=13.4349 Å). The structure has outer [GaTe4 ]5- tetrahedrons and inner [Ag9 Te2 ]5+ clusters. All of the Ag ions are disorderly distributed in the lattice. Seven types of the Ag atoms constitute the cage-like [Ag9 Te2 ]5+ clusters. The highly disordered Ag ions vibrate in-harmonically, producing strong coupling between low frequency optical phonons and acoustic phonons. This in conjunction with a low sound velocity of 1354 m s-1 leads to an ultralow thermal conductivity of 0.20 W m-1 K-1 at 673 K. Meanwhile, the deficiency of Ga in Ag9 Ga1-x Te6 compounds effectively optimizes the electronic transport properties. Ag9 Ga0.91 Te6 attains a highest power factor of 0.40 mW m-1 K-2 at 673 K. All these contribute to a much-improved ZT value of 1.13 at 623 K for Ag9 Ga0.95 Te6 , which is 41 % higher than that of the pristine Ag9 GaTe6 sample.

4.
J Biol Chem ; 294(42): 15446-15465, 2019 10 18.
Artículo en Inglés | MEDLINE | ID: mdl-31481470

RESUMEN

The tight junctional pore-forming protein claudin-2 (CLDN-2) mediates paracellular Na+ and water transport in leaky epithelia and alters cancer cell proliferation. Previously, we reported that tumor necrosis factor-α time-dependently alters CLDN-2 expression in tubular epithelial cells. Here, we found a similar expression pattern in a mouse kidney injury model (unilateral ureteral obstruction), consisting of an initial increase followed by a drop in CLDN-2 protein expression. CLDN-2 silencing in LLC-PK1 tubular cells induced activation and phosphorylation of guanine nucleotide exchange factor H1 (GEF-H1), leading to Ras homolog family member A (RHOA) activation. Silencing of other claudins had no such effects, and re-expression of an siRNA-resistant CLDN-2 prevented RHOA activation, indicating specific effects of CLDN-2 on RHOA. Moreover, kidneys from CLDN-2 knockout mice had elevated levels of active RHOA. Of note, CLDN-2 silencing reduced LLC-PK1 cell proliferation and elevated expression of cyclin-dependent kinase inhibitor P27 (P27KIP1) in a GEF-H1/RHOA-dependent manner. P27KIP1 silencing abrogated the effects of CLDN-2 depletion on proliferation. CLDN-2 loss also activated myocardin-related transcription factor (MRTF), a fibrogenic RHOA effector, and elevated expression of connective tissue growth factor and smooth muscle actin. Finally, CLDN-2 down-regulation contributed to RHOA activation and smooth muscle actin expression induced by prolonged tumor necrosis factor-α treatment, because they were mitigated by re-expression of CLDN-2. Our results indicate that CLDN-2 suppresses GEF-H1/RHOA. CLDN-2 down-regulation, for example, by inflammation, can reduce proliferation and promote MRTF activation through RHOA. These findings suggest that the initial CLDN-2 elevation might aid epithelial regeneration, and CLDN-2 loss could contribute to fibrotic reprogramming.


Asunto(s)
Claudinas/metabolismo , Factores de Intercambio de Guanina Nucleótido Rho/metabolismo , Transactivadores/metabolismo , Obstrucción Ureteral/metabolismo , Proteína de Unión al GTP rhoA/metabolismo , Animales , Claudinas/genética , Femenino , Humanos , Túbulos Renales/metabolismo , Células LLC-PK1 , Masculino , Ratones , Ratones Endogámicos C57BL , Fenotipo , Factores de Intercambio de Guanina Nucleótido Rho/genética , Porcinos , Transactivadores/genética , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/metabolismo , Obstrucción Ureteral/genética , Proteína de Unión al GTP rhoA/genética
5.
Am J Physiol Cell Physiol ; 314(3): C366-C378, 2018 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-29187366

RESUMEN

Claudin-2 (Cldn-2) is a channel-forming tight junction (TJ) protein in the proximal tubules that mediates paracellular Na+ transport and has also emerged as a regulator of proliferation and migration. Expression of Cldn-2 is altered by numerous stimuli, but the underlying mechanisms remain incompletely understood. Here we show that Cldn-2 protein and mRNA expression were low in subconfluent tubular cells and increased during junction maturation. Cldn-1 or occludin did not exhibit similar confluence-dependence. Conversely, disruption of TJs by Ca2+ removal or silencing of zonula occludens-1 (ZO-1) or ZO-2 induced a large drop in Cldn-2 abundance. Immunofluorescent staining revealed a more uneven Cldn-2 staining in nascent, Cldn-1-positive TJs. Subconfluence and ZO-1 silencing augmented Cldn-2 degradation and reduced Cldn-2 promoter activity, suggesting that insertion into the TJs slows Cldn-2 turnover. Indeed, blocking endocytosis or lysosomal degradation increased Cldn-2 abundance. Cell confluence increased expression of the junctional adapters ZO-1 and -2, and the small GTPase Rac, and elevated Rac activity and p21-activated kinase (Pak) phosphorylation, suggesting that they might mediate confluence-dependent Cldn-2 regulation. Indeed, Rac silencing or Pak inhibition strongly reduced Cldn-2 protein abundance, which was likely the combined effect on turnover, as these interventions reduced Cldn-2 promoter activity and augmented Cldn-2 degradation. Taken together, our data suggest that TJ integrity and maturity, ZO-1 expression/TJ localization, and Rac/Pak control Cldn-2 degradation and synthesis. A feedback mechanism connecting Cldn-2 expression with junction remodeling, e.g., during wound healing, epithelial-mesenchymal transition, or tumor metastasis formation, may have important downstream effects on permeability, proliferation, and migration.


Asunto(s)
Comunicación Celular , Proliferación Celular , Claudina-2/metabolismo , Células Epiteliales/metabolismo , Uniones Estrechas/metabolismo , Proteína de la Zonula Occludens-1/metabolismo , Proteínas de Unión al GTP rac/metabolismo , Animales , Senescencia Celular , Claudina-2/genética , Perros , Retroalimentación Fisiológica , Regulación de la Expresión Génica , Células LLC-PK1 , Células de Riñón Canino Madin Darby , Permeabilidad , Estabilidad Proteica , Proteolisis , Transducción de Señal , Porcinos , Proteína de la Zonula Occludens-1/genética , Quinasas p21 Activadas/metabolismo , Proteínas de Unión al GTP rac/genética
6.
J Am Chem Soc ; 140(27): 8578-8585, 2018 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-29909625

RESUMEN

A new state-of-the-art thermoelectric material, Tl2Ag12Te7+δ, which possesses an extremely low thermal conductivity of about 0.25 W m-1 K-1 and a high figure-of-merit of up to 1.1 at 525 K, was obtained using a conventional solid-state reaction approach. Its subcell is a variant of the Zr2Fe12P7 type, but ultimately its structure was refined as a composite structure of a Tl2Ag12Te6 framework and a linear Te atom chain running along the c axis. The super-space group of the framework was determined to be P63(00γ) s with a = b = 11.438(1) Å, c = 4.6256(5) Å, and that of the Te chain substructure has the same a and b axes, but c = 3.212(1) Å, space group P6(00γ) s. The modulation leads to the formation of Te2 and Te3 fragments in this chain and a refined formula of Tl2Ag11.5Te7.4. The structure consists of a complex network of three-dimensionally connected AgTe4 tetrahedra forming channels filled with the Tl atoms. The electronic structures of four different models comprising different Te chains, Tl2Ag12Te7, Tl2Ag12Te7.33, and 2× Tl2Ag12Te7.5, were computed using the WIEN2k package. Depending on the Te content within the chain, the models are either semiconducting or metallic. Physical property measurements revealed semiconducting properties, with an ultralow thermal conductivity, and excellent thermoelectric properties at elevated temperatures.

7.
J Biol Chem ; 290(35): 21603-14, 2015 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-26175156

RESUMEN

We previously showed that ADAM17 mediates high glucose-induced matrix production by kidney mesangial cells. ADAM17 expression is increased in diabetic kidneys, suggesting that its up-regulation may augment high glucose profibrotic responses. We thus studied the effects of high glucose on ADAM17 gene regulation. Primary rat mesangial cells were treated with high glucose (30 mm) or mannitol as osmotic control. High glucose dose-dependently increased ADAM17 promoter activity, transcript, and protein levels. This correlated with augmented ADAM17 activity after 24 h versus 1 h of high glucose. We tested involvement of transcription factors shown in other settings to regulate ADAM17 transcription. Promoter activation was not affected by NF-κB or Sp1 inhibitors, but was blocked by hypoxia-inducible factor-1α (HIF-1α) inhibition or down-regulation. This also prevented ADAM17 transcript and protein increases. HIF-1α activation by high glucose was shown by its increased nuclear translocation and activation of the HIF-responsive hypoxia-response element (HRE)-luciferase reporter construct. Assessment of ADAM17 promoter deletion constructs coupled with mutation analysis and ChIP studies identified HIF-1α binding to its consensus element at -607 as critical for the high glucose response. Finally, inhibitors of epidermal growth factor receptor (EGFR) and downstream PI3K/Akt, or ADAM17 itself, prevented high glucose-induced HIF-1α activation and ADAM17 up-regulation. Thus, high glucose induces ADAM17 transcriptional up-regulation in mesangial cells, which is associated with augmentation of its activity. This is mediated by HIF-1α and requires EGFR/ADAM17 signaling, demonstrating the potentiation by ADAM17 of its own up-regulation. ADAM17 inhibition thus provides a potential novel therapeutic strategy for the treatment of diabetic nephropathy.


Asunto(s)
Proteínas ADAM/metabolismo , Glucosa/farmacología , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Células Mesangiales/metabolismo , Regulación hacia Arriba/efectos de los fármacos , Proteínas ADAM/genética , Proteína ADAM17 , Animales , Hipoxia de la Célula/efectos de los fármacos , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patología , Receptores ErbB/metabolismo , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Retroalimentación Fisiológica , Riñón/efectos de los fármacos , Riñón/patología , Ligandos , Masculino , Células Mesangiales/efectos de los fármacos , Ratones Endogámicos C57BL , Modelos Biológicos , Fosfatidilinositol 3-Quinasas/metabolismo , Regiones Promotoras Genéticas/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratas Sprague-Dawley , Elementos de Respuesta/genética , Transducción de Señal/efectos de los fármacos
8.
Diabetologia ; 58(10): 2443-54, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26232095

RESUMEN

AIMS/HYPOTHESIS: We investigated whether heterogeneous nuclear ribonucleoprotein F (hnRNP F) stimulates renal ACE-2 expression and prevents TGF-ß1 signalling, TGF-ß1 inhibition of Ace-2 gene expression and induction of tubulo-fibrosis in an Akita mouse model of type 1 diabetes. METHODS: Adult male Akita transgenic (Tg) mice overexpressing specifically hnRNP F in their renal proximal tubular cells (RPTCs) were studied. Non-Akita littermates and Akita mice served as controls. Immortalised rat RPTCs stably transfected with plasmid containing either rat Hnrnpf cDNA or rat Ace-2 gene promoter were also studied. RESULTS: Overexpression of hnRNP F attenuated systemic hypertension, glomerular filtration rate, albumin/creatinine ratio, urinary angiotensinogen (AGT) and angiotensin (Ang) II levels, renal fibrosis and profibrotic gene (Agt, Tgf-ß1, TGF-ß receptor II [Tgf-ßrII]) expression, stimulated anti-profibrotic gene (Ace-2 and Ang 1-7 receptor [MasR]) expression, and normalised urinary Ang 1-7 level in Akita Hnrnpf-Tg mice as compared with Akita mice. In vitro, hnRNP F overexpression stimulated Ace-2 gene promoter activity, mRNA and protein expression, and attenuated Agt, Tgf-ß1 and Tgf-ßrII gene expression. Furthermore, hnRNP F overexpression prevented TGF-ß1 signalling and TGF-ß1 inhibition of Ace-2 gene expression. CONCLUSIONS/INTERPRETATION: These data demonstrate that hnRNP F stimulates Ace-2 gene transcription, prevents TGF-ß1 inhibition of Ace-2 gene transcription and induction of kidney injury in diabetes. HnRNP F may be a potential target for treating hypertension and renal fibrosis in diabetes.


Asunto(s)
Diabetes Mellitus Experimental/metabolismo , Nefropatías Diabéticas/metabolismo , Ribonucleoproteína Heterogénea-Nuclear Grupo F-H/metabolismo , Peptidil-Dipeptidasa A/metabolismo , Factor de Crecimiento Transformador beta1/farmacología , Enzima Convertidora de Angiotensina 2 , Animales , Glucemia/metabolismo , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/patología , Nefropatías Diabéticas/genética , Nefropatías Diabéticas/patología , Expresión Génica/efectos de los fármacos , Ribonucleoproteína Heterogénea-Nuclear Grupo F-H/genética , Riñón/metabolismo , Riñón/patología , Ratones , Ratones Transgénicos , Peptidil-Dipeptidasa A/genética
9.
Clin Sci (Lond) ; 128(10): 649-63, 2015 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-25495544

RESUMEN

We investigated the relationship between Ang-(1-7) [angiotensin-(1-7)] action, sHTN (systolic hypertension), oxidative stress, kidney injury, ACE2 (angiotensin-converting enzyme-2) and MasR [Ang-(1-7) receptor] expression in Type 1 diabetic Akita mice. Ang-(1-7) was administered daily [500 µg/kg of BW (body weight) per day, subcutaneously] to male Akita mice from 14 weeks of age with or without co-administration of an antagonist of the MasR, A779 (10 mg/kg of BW per day). The animals were killed at 20 weeks of age. Age-matched WT (wild-type) mice served as controls. Ang-(1-7) administration prevented sHTN and attenuated kidney injury (reduced urinary albumin/creatinine ratio, glomerular hyperfiltration, renal hypertrophy and fibrosis, and tubular apoptosis) without affecting blood glucose levels in Akita mice. Ang-(1-7) also attenuated renal oxidative stress and the expression of oxidative stress-inducible proteins (NADPH oxidase 4, nuclear factor erythroid 2-related factor 2, haem oxygenase 1), pro-hypertensive proteins (angiotensinogen, angiotensin-converting enzyme, sodium/hydrogen exchanger 3) and profibrotic proteins (transforming growth factor-ß1 and collagen IV), and increased the expression of anti-hypertensive proteins (ACE2 and MasR) in Akita mouse kidneys. These effects were reversed by A779. Our data suggest that Ang-(1-7) plays a protective role in sHTN and RPTC (renal proximal tubular cell) injury in diabetes, at least in part, through decreasing renal oxidative stress-mediated signalling and normalizing ACE2 and MasR expression.


Asunto(s)
Angiotensina I/farmacología , Diabetes Mellitus Tipo 1/complicaciones , Fibrosis/prevención & control , Hipertensión/prevención & control , Enfermedades Renales/prevención & control , Estrés Oxidativo/efectos de los fármacos , Fragmentos de Péptidos/farmacología , Análisis de Varianza , Angiotensina I/administración & dosificación , Angiotensina I/uso terapéutico , Angiotensina I/orina , Angiotensina II/análogos & derivados , Enzima Convertidora de Angiotensina 2 , Animales , Glucemia , Western Blotting , Fibrosis/etiología , Regulación de la Expresión Génica/efectos de los fármacos , Técnicas Histológicas , Hipertensión/etiología , Inmunohistoquímica , Inyecciones Subcutáneas , Enfermedades Renales/etiología , Túbulos Renales Proximales/efectos de los fármacos , Túbulos Renales Proximales/metabolismo , Masculino , Ratones , Fragmentos de Péptidos/administración & dosificación , Fragmentos de Péptidos/uso terapéutico , Fragmentos de Péptidos/orina , Peptidil-Dipeptidasa A/metabolismo , Proto-Oncogenes Mas , Proteínas Proto-Oncogénicas/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptores Acoplados a Proteínas G/metabolismo
10.
Sci Total Environ ; 924: 171607, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38461993

RESUMEN

Phthalates, classified as environmental endocrine disruptors, pose potential toxicity risks to human health. Metabolic dysfunction-associated fatty liver disease is one of the most widespread liver diseases globally. Compared to studies focusing on metabolic disorders in relation to pollutants exposure, the impact of individual factors such as fatty liver on the in vivo metabolism of pollutants is always overlooked. Therefore, this study measured concentrations and composition of phthalate monoesters (mPAEs) in human urine samples, particularly those from fatty liver patients. Furthermore, we induced fatty liver in male Wistar rats by formulating a high-fat diet for twelve weeks. After administering a single dose of DEHP at 500 mg/kg bw through gavage, we compared the levels of di-2-ethylhexyl phthalate (DEHP), its metabolites (mDEHPs) and three hepatic metabolic enzymes, namely cytochrome P450 enzymes (CYP450), UDP glucuronosyltransferase 1 (UGT1), and carboxylesterase 1 (CarE1), between the normal and fatty liver rat groups. Compared to healthy individuals (n = 75), fatty liver patients (n = 104) exhibited significantly lower urinary concentrations of ∑mPAEs (median: 106 vs. 166 ng/mL), but with a higher proportion of mono-2-ethylhexyl phthalate in ∑mDEHPs (25.7 % vs. 9.9 %) (p < 0.05). In the animal experiment, we found that fatty liver in rats prolonged the elimination half-life of DEHP (24.61 h vs. 18.89 h) and increased the contents of CYP450, CarE1, and UGT1, implying the common but differentiated metabolism of DEHP as excess lipid accumulation in liver cells. This study provides valuable information on how to distinguish populations in biomonitoring studies across a diverse population and in assigning exposure classifications of phthalates or similar chemicals in epidemiologic studies.


Asunto(s)
Dietilhexil Ftalato , Contaminantes Ambientales , Enfermedad del Hígado Graso no Alcohólico , Ácidos Ftálicos , Humanos , Masculino , Ratas , Animales , Dietilhexil Ftalato/metabolismo , Exposición a Riesgos Ambientales , Ratas Wistar , Ácidos Ftálicos/orina , Contaminantes Ambientales/metabolismo , Biomarcadores
11.
J Colloid Interface Sci ; 658: 362-372, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38113545

RESUMEN

Formic acid (FA) holds significant potential as a liquid hydrogen storage medium. However, it is important to improve the reaction rates and extend the practical applications of FA dehydrogenation and Cr(VI) reduction through the development of efficient heterogeneous catalysts. This study reports the synthesis of a uniformly dispersed PdAuIr nanoparticles (NPs) catalyst loaded with amine groups covalent organic frameworks (COFs). The alloyed NPs demonstrated exceptional effectiveness in FA dehydrogenation rate and Cr(VI) reduction. The initial turnover of frequency (TOF) value for FA dehydrogenation without additives was 9970 h-1 at 298 K, the apparent activation energy (Ea) was 30.3 kJ/mol and the rate constant (k) for Cr(VI) reduction was 0.742 min-1. Additionally, it showcased the ability to undergo recycling up to six times with minimal degradation in performance. The results indicate that its remarkable catalytic performance can be attributed primarily to the favorable mass transfer attributes of the aminated COFs supports, the strong metal-support interaction (SMSI), and the synergistic effects among the metals. This study offers a novel perspective on the advancement of efficient and durable heterogeneous catalysts with diverse capabilities, thereby making significant contributions to the fields of energy and environmental preservation.

12.
Front Plant Sci ; 15: 1346154, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38799095

RESUMEN

Numerous bacteria, fungi and other microorganisms in the tobacco phyllosphere interstellar area participate in the physiological metabolism of plants by interacting with the host. However, there is currently little research on the characteristics of tobacco phyllosphere microbial communities, and the correlation between tobacco phyllosphere microbial communities and phyllosphere factor indicators is still unknown. Therefore, high-throughput sequencing technology based on the 16S rRNA/ITS1 gene was used to explore the diversity and composition characteristics of tobacco phyllosphere bacterial and fungal communities from different maturation processes, and to identify marker genera that distinguish phyllosphere microbial communities. In this study, the correlations between tobacco phyllosphere bacterial and fungal communities and the precursors of major aroma compounds were explored. The results showed that as the tobacco plants matured, the density of glandular trichomes on the tobacco leaves gradually decreased. The surface physicochemical properties of tobacco leaves also undergo significant changes. In addition, the overall bacterial alpha diversity in the tobacco phyllosphere area increased with maturation, while the overall fungal alpha diversity decreased. The beta diversity of bacteria and fungi in the tobacco phyllosphere area also showed significant differences. Specifically, with later top pruning time, the relative abundances of Acidisoma, Ralstonia, Bradyrhizobium, Alternaria and Talaromyces gradually increased, while the relative abundances of Pseudomonas, Filobassidium, and Tausonia gradually decreased. In the bacterial community, Acidisoma, Ralstonia, Bradyrhizobium, and Alternaria were significantly positively correlated with tobacco aroma precursors, with significant negative correlations with tobacco phyllosphere trichome morphology, while Pseudomonas showed the opposite pattern; In the fungal community, Filobasidium and Tausonia were significantly negatively correlated with tobacco aroma precursors, and significantly positively correlated with tobacco phyllosphere trichome morphology, while Alternaria showed the opposite pattern. In conclusion, the microbiota (bacteria and fungi) and aroma precursors of the tobacco phyllosphere change significantly as tobacco matures. The presence of Acidisoma, Ralstonia, Bradyrhizobium and Alternaria in the phyllosphere microbiota of tobacco may be related to the aroma precursors of tobacco.

13.
Am J Physiol Renal Physiol ; 304(11): F1335-46, 2013 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-23552863

RESUMEN

We investigated the relationship among oxidative stress, hypertension, renal injury, and angiotensin-converting enzyme-2 (ACE2) expression in type 1 diabetic Akita mice. Blood glucose, blood pressure, and albuminuria were monitored for up to 5 mo in adult male Akita and Akita catalase (Cat) transgenic (Tg) mice specifically overexpressing Cat, a key antioxidant enzyme in their renal proximal tubular cells (RPTCs). Same-age non-Akita littermates and Cat-Tg mice served as controls. In separate studies, adult male Akita mice (14 wk) were treated with ANG 1-7 (500 µg·kg⁻¹·day⁻¹ sc) ± A-779, an antagonist of the Mas receptor (10 mg·kg⁻¹·day⁻¹ sc), and euthanized at the age of 18 wk. The left kidneys were processed for histology and apoptosis studies. Renal proximal tubules were isolated from the right kidneys to assess protein and gene expression. Urinary angiotensinogen (AGT), angiotensin II (ANG II), and ANG 1-7 were quantified by specific ELISAs. Overexpression of Cat attenuated renal oxidative stress; prevented hypertension; normalized RPTC ACE2 expression and urinary ANG 1-7 levels (both were low in Akita mice); ameliorated glomerular filtration rate, albuminuria, kidney hypertrophy, tubulointerstitial fibrosis, and tubular apoptosis; and suppressed profibrotic and proapoptotic gene expression in RPTCs of Akita Cat-Tg mice compared with Akita mice. Furthermore, daily administration of ANG 1-7 normalized systemic hypertension in Akita mice, which was reversed by A-779. These data demonstrate that Cat overexpression prevents hypertension and progression of nephropathy and highlight the importance of intrarenal oxidative stress and ACE2 expression contributing to hypertension and renal injury in diabetes.


Asunto(s)
Catalasa/metabolismo , Diabetes Mellitus Tipo 1/fisiopatología , Hipertensión/prevención & control , Túbulos Renales/patología , Estrés Oxidativo , Peptidil-Dipeptidasa A/metabolismo , Albuminuria , Angiotensina I/administración & dosificación , Angiotensina I/orina , Enzima Convertidora de Angiotensina 2 , Angiotensinógeno/orina , Animales , Apoptosis , Catalasa/genética , Diabetes Mellitus Tipo 1/complicaciones , Diabetes Mellitus Tipo 1/patología , Nefropatías Diabéticas/patología , Nefropatías Diabéticas/fisiopatología , Nefropatías Diabéticas/prevención & control , Fibrosis , Hipertensión/etiología , Riñón/patología , Túbulos Renales Proximales/patología , Masculino , Ratones , Ratones Transgénicos , Fragmentos de Péptidos/administración & dosificación , Fragmentos de Péptidos/orina
14.
Acta Biomater ; 167: 16-37, 2023 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-37331614

RESUMEN

With the advancement of additive manufacturing (AM), customized vascular stents can now be fabricated to fit the curvatures and sizes of a narrowed or blocked blood vessel, thereby reducing the possibility of thrombosis and restenosis. More importantly, AM enables the design and fabrication of complex and functional stent unit cells that would otherwise be impossible to realize with conventional manufacturing techniques. Additionally, AM makes fast design iterations possible while also shortening the development time of vascular stents. This has led to the emergence of a new treatment paradigm in which custom and on-demand-fabricated stents will be used for just-in-time treatments. This review is focused on the recent advances in AM vascular stents aimed at meeting the mechanical and biological requirements. First, the biomaterials suitable for AM vascular stents are listed and briefly described. Second, we review the AM technologies that have been so far used to fabricate vascular stents as well as the performances they have achieved. Subsequently, the design criteria for the clinical application of AM vascular stents are discussed considering the currently encountered limitations in materials and AM techniques. Finally, the remaining challenges are highlighted and some future research directions are proposed to realize clinically-viable AM vascular stents. STATEMENT OF SIGNIFICANCE: Vascular stents have been widely used for the treatment of vascular disease. The recent progress in additive manufacturing (AM) has provided unprecedented opportunities for revolutionizing traditional vascular stents. In this manuscript, we review the applications of AM to the design and fabrication of vascular stents. This is an interdisciplinary subject area that has not been previously covered in the published review articles. Our objective is to not only present the state-of-the-art of AM biomaterials and technologies but to also critically assess the limitations and challenges that need to be overcome to speed up the clinical adoption of AM vascular stents with both anatomical superiority and mechanical and biological functionalities that exceed those of the currently available mass-produced devices.


Asunto(s)
Materiales Biocompatibles , Enfermedades Vasculares , Humanos , Stents , Tecnología
15.
Am J Physiol Renal Physiol ; 302(7): F840-52, 2012 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-22205225

RESUMEN

We investigated the effects of dual renin-angiotensin system (RAS) blockade on angiotensin-converting enzyme-2 (Ace2) expression, hypertension, and renal proximal tubular cell (RPTC) apoptosis in type 1 diabetic Akita angiotensinogen (Agt)-transgenic (Tg) mice that specifically overexpress Agt in their RPTCs. Adult (11 wk old) male Akita and Akita Agt-Tg mice were treated with two RAS blockers (ANG II receptor type 1 blocker losartan, 30 mg·kg(-1)·day(-1)) and angiotensin-converting enzyme (ACE) inhibitor perindopril (4 mg·kg(-1)·day(-1)) in drinking water. Same-age non-Akita littermates and Agt-Tg mice served as controls. Blood pressure, blood glucose, and albuminuria were monitored weekly. The animals were euthanized at age 16 wk. The left kidneys were processed for immunohistochemistry and apoptosis studies. Renal proximal tubules were isolated from the right kidneys to assess gene and protein expression. Urinary ANG II and ANG 1-7 were quantified by ELISA. RAS blockade normalized renal Ace2 expression and urinary ANG 1-7 levels (both of which were low in untreated Akita and Akita Agt-Tg), prevented hypertension, albuminuria, tubulointerstitial fibrosis and tubular apoptosis, and inhibited profibrotic and proapoptotic gene expression in RPTCs of Akita and Akita Agt-Tg mice compared with non-Akita controls. Our results demonstrate the effectiveness of RAS blockade in preventing intrarenal RAS activation, hypertension, and nephropathy progression in diabetes and support the important role of intrarenal Ace2 expression in modulating hypertension and renal injury in diabetes.


Asunto(s)
Angiotensinógeno/metabolismo , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Nefropatías Diabéticas/etiología , Túbulos Renales Proximales/metabolismo , Bloqueadores del Receptor Tipo 1 de Angiotensina II/farmacología , Enzima Convertidora de Angiotensina 2 , Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Angiotensinógeno/genética , Animales , Apoptosis , Nefropatías Diabéticas/metabolismo , Nefropatías Diabéticas/patología , Expresión Génica , Hipertensión/etiología , Riñón/metabolismo , Riñón/patología , Losartán/farmacología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Nefroesclerosis/metabolismo , Peptidil-Dipeptidasa A/metabolismo , Perindopril/farmacología , Ratas , Sistema Renina-Angiotensina/efectos de los fármacos , Transgenes
16.
RSC Adv ; 11(30): 18525-18538, 2021 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-35480906

RESUMEN

The recycling of agricultural and food waste is an effective way to reduce resource waste and ameliorate the shortage of natural resources. The treatment of antibiotic wastewater is a current research hotspot. In this study, waste tea residue was used as a raw material to prepare biochar (T-BC) and loaded with Fe3O4 as a catalyst to activate peroxymonosulfate (PMS) for oxidative degradation of tetracycline hydrochloride (TCH). Analysis techniques such as BET, SEM, XRD, FT-IR, XPS and VSM indicated that the heterogeneous catalyst (Fe3O4@T-BC) with good surface properties and magnetic properties was successfully prepared. The results of batch-scale experiments illustrated that when the dose of the Fe3O4@T-BC catalyst was 1 g L-1, the concentration of PMS was 1 g L-1, and the initial pH was 7, the degradation rate of TCH with a concentration of 50 mg L-1 reached 97.89% after 60 minutes of reaction. When the initial pH was 11, the degradation rate of TCH reached 99.86%. After the catalyst was recycled four times using an external magnet, the degradation rate of TCH could still reach 71.32%. The data of removal of TCH could be best fitted by a pseudo-first-order model. The analysis of the degradation mechanism through a free radical quenching experiment and EPR analysis, as well as the exploration of TCH intermediate products and reaction paths through the LC-MS method, all confirmed that the Fe3O4@T-BC prepared by this method is expected to become a cost-effective and environmentally friendly heterogeneous catalyst for activating persulfate degradation of tetracycline antibiotics.

17.
ACS Appl Mater Interfaces ; 11(49): 45629-45635, 2019 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-31738048

RESUMEN

In this work, polycrystalline n-type Mg2Si0.30Sn0.67Bi0.03 dispersed with x wt % ß-SiC nanoparticles (x = 0, 0.5, 1.0, 1.5, and 3.0) thermoelectric materials were fabricated by a solid-state reaction in a low-cost container, consolidated by hot-pressing. We obtained figure of merit values zT above 1.4 at 773 K along with enhanced mechanical properties by adding ß-SiC into an Mg2Si0.30Sn0.67Bi0.03 matrix. Incorporation of SiC nanoparticles has thusly simultaneously increased toughness and, depending on the SiC content, thermoelectric performance. The peak figure of merit was improved from zT = 1.33 for Mg2Si0.30Sn0.67Bi0.03 to 1.45 for Mg2Si0.30Sn0.67Bi0.03 with 3 wt % at 773 K.

18.
Dalton Trans ; 48(25): 9357-9364, 2019 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-31172165

RESUMEN

The title materials have been reported earlier to be p-type thermoelectrics when x = 0.1 and y = 0. Here, we studied the properties after varying the Cu and the Se/Te concentrations. At first, materials with the same nominal Cu concentration, 5.9 Cu per formula unit, and different Se/Te ratios were prepared. The different thermoelectric properties indicated that the Se/Te ratio strongly affected the Cu deficiency, which is directly responsible for the charge carrier concentration. Single crystal structure data revealed the Cu amount to be less than 5.8 per formula unit when y = 0.4; therefore a sample of nominal composition "BaCu5.74Se0.46Te6.54" was also studied. This sample exhibited an electrical conductivity of 685 Ω-1 cm-1 at room temperature, which is almost three times larger than in case of "BaCu5.9SeTe6", in accord with the lower Cu amount causing a larger hole concentration. The larger mass fluctuation on the Se/Te site resulted in a lower lattice thermal conductivity, but the decreased Seebeck coefficient mitigated a performance increase in form of a higher figure-of-merit. In contrast to other Cu chalcogenides, the data are reproducible under the measurement conditions.

19.
Diabetes ; 66(7): 1964-1978, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28424160

RESUMEN

We investigated the mechanism of heterogeneous nuclear ribonucleoprotein F (hnRNP F) renoprotective action in a type 2 diabetes (T2D) mouse model (db/db). Immortalized rat renal proximal tubular cells (IRPTCs) and kidneys from humans with T2D were also studied. The db/db mice developed hyperglycemia, oxidative stress, and nephropathy at age 20 weeks compared with their db/m littermates. These abnormalities, with the exception of hyperglycemia, were attenuated in db/dbhnRNP F-transgenic (Tg) mice specifically overexpressing hnRNP F in their RPTCs. Sirtuin-1, Foxo3α, and catalase expression were significantly decreased in RPTCs from db/db mice and normalized in db/dbhnRNP F-Tg mice. In vitro, hnRNP F overexpression stimulated Sirtuin-1 and Foxo3α with downregulation of acetylated p53 expression and prevented downregulation of Sirtuin-1 and Foxo3α expression in IRPTCs by high glucose plus palmitate. Transfection of Sirtuin-1 small interfering RNA prevented hnRNP F stimulation of Foxo3α and downregulation of acetylated p53 expression. hnRNP F stimulated Sirtuin-1 transcription via hnRNP F-responsive element in the Sirtuin-1 promoter. Human T2D kidneys exhibited more RPTC apoptosis and lower expression of hnRNP F, SIRTUIN-1, and FOXO3α than nondiabetic kidneys. Our results demonstrate that hnRNP F protects kidneys against oxidative stress and nephropathy via stimulation of Sirtuin-1 expression and signaling in diabetes.


Asunto(s)
Diabetes Mellitus Experimental/genética , Diabetes Mellitus Tipo 2/genética , Nefropatías Diabéticas/genética , Ribonucleoproteína Heterogénea-Nuclear Grupo F-H/genética , Túbulos Renales Proximales/metabolismo , Riñón/metabolismo , Sirtuina 1/genética , Acetilación , Anciano , Animales , Apoptosis , Western Blotting , Estudios de Casos y Controles , Células Cultivadas , Diabetes Mellitus Experimental/complicaciones , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/metabolismo , Nefropatías Diabéticas/etiología , Nefropatías Diabéticas/metabolismo , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Femenino , Fibrosis , Proteína Forkhead Box O3 , Regulación de la Expresión Génica/genética , Ribonucleoproteína Heterogénea-Nuclear Grupo F-H/metabolismo , Humanos , Inmunohistoquímica , Etiquetado Corte-Fin in Situ , Técnicas In Vitro , Riñón/patología , Masculino , Ratones , Ratones Noqueados , Ratones Transgénicos , Persona de Mediana Edad , Estrés Oxidativo , Ratas , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptores de Leptina/genética , Sirtuina 1/metabolismo , Proteína p53 Supresora de Tumor/metabolismo
20.
Endocrinology ; 158(4): 903-919, 2017 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-28324005

RESUMEN

Oxidative stress induces endogenous antioxidants via nuclear factor erythroid 2-related factor 2 (Nrf2), potentially preventing tissue injury. We investigated whether insulin affects renal Nrf2 expression in type 1 diabetes (T1D) and studied its underlying mechanism. Insulin normalized hyperglycemia, hypertension, oxidative stress, and renal injury; inhibited renal Nrf2 and angiotensinogen (Agt) gene expression; and upregulated heterogeneous nuclear ribonucleoprotein F and K (hnRNP F and hnRNP K) expression in Akita mice with T1D. In immortalized rat renal proximal tubular cells, insulin suppressed Nrf2 and Agt but stimulated hnRNP F and hnRNP K gene transcription in high glucose via p44/42 mitogen-activated protein kinase signaling. Transfection with small interfering RNAs of p44/42 MAPK, hnRNP F, or hnRNP K blocked insulin inhibition of Nrf2 gene transcription. Insulin curbed Nrf2 promoter activity via a specific DNA-responsive element that binds hnRNP F/K, and hnRNP F/K overexpression curtailed Nrf2 promoter activity. In hyperinsulinemic-euglycemic mice, renal Nrf2 and Agt expression was downregulated, whereas hnRNP F/K expression was upregulated. Thus, the beneficial actions of insulin in diabetic nephropathy appear to be mediated, in part, by suppressing renal Nrf2 and Agt gene transcription and preventing Nrf2 stimulation of Agt expression via hnRNP F/K. These findings identify hnRNP F/K and Nrf2 as potential therapeutic targets in diabetes.


Asunto(s)
Angiotensinógeno/genética , Diabetes Mellitus Tipo 1/genética , Ribonucleoproteína Heterogénea-Nuclear Grupo F-H/genética , Ribonucleoproteína Heterogénea-Nuclear Grupo K/genética , Insulina/farmacología , Factor 2 Relacionado con NF-E2/genética , Transcripción Genética/efectos de los fármacos , Angiotensinógeno/metabolismo , Animales , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Diabetes Mellitus Tipo 1/metabolismo , Nefropatías Diabéticas/tratamiento farmacológico , Nefropatías Diabéticas/genética , Nefropatías Diabéticas/metabolismo , Expresión Génica/efectos de los fármacos , Ribonucleoproteína Heterogénea-Nuclear Grupo F-H/metabolismo , Ribonucleoproteína Heterogénea-Nuclear Grupo K/metabolismo , Insulina/uso terapéutico , Riñón/efectos de los fármacos , Riñón/metabolismo , Masculino , Ratones , Ratones Transgénicos , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Regiones Promotoras Genéticas/efectos de los fármacos , Transducción de Señal/efectos de los fármacos
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