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1.
Am J Kidney Dis ; 76(1): 90-99, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32197881

RESUMO

RATIONALE & OBJECTIVE: Hematuria is the most typical presentation of immunoglobulin A nephropathy (IgAN); however, its role in disease progression is still controversial. This study aimed to evaluate the association of hematuria and progression of IgAN. STUDY DESIGN: Retrospective cohort study. SETTING & PARTICIPANTS: A cohort of 1,333 patients with IgAN treated at a Chinese referral hospital with a median follow-up of 45 months. PREDICTORS: Microhematuria was evaluated in fresh urine using a fully automated urine particle analyzer (automated method) and urine sediment examination by a skilled examiner (manual method). Hematuria was characterized as a time-varying attribute; namely, average hematuria level was calculated for every 6-month period for each patient during follow-up. Remission was defined as average red blood cell count ≤5/high-power field (manual method) or ≤28 red blood cells/µL (automated method) during the first 6 months of follow-up. OUTCOMES: Composite event of 50% decline in estimated glomerular filtration rate or development of kidney failure. ANALYTICAL APPROACH: Multivariable cause-specific hazards models to analyze the relationship between hematuria and the composite kidney disease progression event. RESULTS: Time-varying hematuria during follow-up was an independent risk factor for the composite kidney disease progression event (HR, 1.46; 95% CI, 1.13-1.87; P = 0.003). Hematuria remission during the 6 months after diagnosis was associated with a significantly lower rate of the composite kidney disease progression event (HR, 0.41; 95% CI, 0.28-0.61; P < 0.001). A significant interaction was detected between remission of proteinuria and remission of hematuria during the first 6 months (P < 0.001). The association between remission of hematuria and kidney disease progression was detectable (HR, 0.46; 95% CI, 0.32-0.68) within the subpopulation with persistent proteinuria (protein excretion > 1.0 g/d during the first 6 months), but not among patients whose proteinuria had remitted (HR, 0.64; 95% CI, 0.31-1.29; P = 0.2). The 2 techniques for hematuria evaluation were strongly and significantly linearly correlated (r = 0.948; P < 0.001), and results using these 2 methods were consistent. LIMITATIONS: A single-center retrospective study. Proportional hazards regression incorporating time-varying covariates may create time-varying confounding. The predictive value of reductions in hematuria was not directly evaluated. CONCLUSIONS: Level of hematuria was independently associated with kidney disease progression, whereas hematuria remission was associated with improved kidney outcomes in IgAN among patients with persistent proteinuria. Additionally, to monitor IgAN progression, automated methods to evaluate hematuria hold promise as a replacement for manual evaluation of urinary sediment.


Assuntos
Progressão da Doença , Glomerulonefrite por IGA/diagnóstico , Glomerulonefrite por IGA/epidemiologia , Hematúria/diagnóstico , Hematúria/epidemiologia , Adulto , Estudos de Coortes , Feminino , Seguimentos , Glomerulonefrite por IGA/sangue , Hematúria/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Insuficiência Renal/sangue , Insuficiência Renal/diagnóstico , Insuficiência Renal/epidemiologia , Estudos Retrospectivos
2.
Biomass Convers Biorefin ; : 1-15, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36785542

RESUMO

A deep eutectic solvent (choline chloride (ChCl)-urea) was chosen to extract flavonoids from Moringa oleifera leaves (FMOL), the condition of extraction was tailor-made, under the optimal extraction conditions (material-to-liquid ratio of 1:60 g/mL, extraction time of 80 min, extraction temperature of 80 °C), the highest extraction efficiency reached 63.2 ± 0.3 mg R/g DW, and nine flavonoids were identified. Then, the biological activities including antioxidant activities, antibacterial activities, and anti-tumor activities were systematically studied. FMOL was superior to positive drugs in terms of antioxidant activity. As to DPPH investigation, the IC50 of FMOL and Vc were 64.1 ± 0.7 and 176.1 ± 2.0 µg/mL; for the ABTS, the IC50 of FMOL and Vc were 9.5 ± 0.3 and 38.2 ± 1.2 µg/mL, the FRAP value of FMOL and Vc were 15.5 ± 0.6 and 10.2 ± 0.4 mg TE/g, and ORAC value of FMOL and Vc were 4687.2 ± 102.8 and 3881.6 ± 98.6 µmol TE/g. The bacteriostatic (MICs were ≤ 1.25 mg/mL) activities of FMOL were much better than propyl p-hydroxybenzoate. Meanwhile, FMOL had comparable inhibitory activity with genistein on tumor cells, IC50 was 307.8 µg/mL, and could effectively induce apoptosis in HCT116. Microcapsules were prepared with xylose-modified soybean protein isolate and gelatin as wall materials; after that, the intestinal release of modified FMOL microcapsules was 86 times of free FMOL. Therefore, this study confirmed that FMOL extracted with ChCl/urea has rich bioactive components, and microencapsulated FMOL has potential application in food industry. Supplementary Information: The online version contains supplementary material available at 10.1007/s13399-023-03877-8.

3.
Adv Mater ; 34(19): e2110518, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35257424

RESUMO

Two decades after the rapid expansion of photovoltaics, the number of solar panels reaching end-of-life is increasing. While precious metals such as silver and copper are usually recycled, silicon, which makes up the bulk of a solar cells, goes to landfills. This is due to the defect- and impurity-sensitive nature in most silicon-based technologies, rendering it uneconomical to purify waste silicon. Thermoelectrics represents a rare class of material in which defects and impurities can be engineered to enhance the performance. This is because of the majority-carrier nature, making it defect- and impurity-tolerant. Here, the upcycling of silicon from photovoltaic (PV) waste into thermoelectrics is enabled. This is done by doping 1% Ge and 4% P, which results in a figure of merit (zT) of 0.45 at 873 K, the highest among silicon-based thermoelectrics. The work represents an important piece of the puzzle in realizing a circular economy for photovoltaics and electronic waste.

4.
Science ; 373(6554): 556-561, 2021 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-34326238

RESUMO

Thermoelectric materials transfer heat and electrical energy, hence they are useful for power generation or cooling applications. Many of these materials have narrow bandgaps, especially for cooling applications. We developed SnSe crystals with a wide bandgap (E g ≈ 33 k B T) with attractive thermoelectric properties through Pb alloying. The momentum and energy multiband alignments promoted by Pb alloying resulted in an ultrahigh power factor of ~75 µW cm-1 K-2 at 300 K, and an average figure of merit ZT of ~1.90. We found that a 31-pair thermoelectric device can produce a power generation efficiency of ~4.4% and a cooling ΔT max of ~45.7 K. These results demonstrate that wide-bandgap compounds can be used for thermoelectric cooling applications.

5.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 2): o330, 2010 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-21579760

RESUMO

The structure of the title compound, C(14)H(12)N(4)O(2), was determined as part of a project on the coordination chemistry of 1,2,4-triazole derivatives. In the crystal structure, one of the two benzene rings is almost coplanar with the five-membered triazole ring (mean deviation = 0.019 Å), whereas the second benzene ring is rotated by 51.973 (2)°. The two N-C-N-N torsion angles [170.365 (2) and -170.942 (3)°] indicate that the amido group is slightly twisted away from the triazole plane. An intra-molecular O-H⋯N hydrogen bond occurs. In the crystal structure, inter-molecular N-H⋯O and O-H⋯N hydrogen bonding is found.

6.
Science ; 365(6460): 1418-1424, 2019 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-31604269

RESUMO

Thermoelectric technology allows conversion between heat and electricity. Many good thermoelectric materials contain rare or toxic elements, so developing low-cost and high-performance thermoelectric materials is warranted. Here, we report the temperature-dependent interplay of three separate electronic bands in hole-doped tin sulfide (SnS) crystals. This behavior leads to synergistic optimization between effective mass (m*) and carrier mobility (µ) and can be boosted through introducing selenium (Se). This enhanced the power factor from ~30 to ~53 microwatts per centimeter per square kelvin (µW cm-1 K-2 at 300 K), while lowering the thermal conductivity after Se alloying. As a result, we obtained a maximum figure of merit ZT (ZT max) of ~1.6 at 873 K and an average ZT (ZT ave) of ~1.25 at 300 to 873 K in SnS0.91Se0.09 crystals. Our strategy for band manipulation offers a different route for optimizing thermoelectric performance. The high-performance SnS crystals represent an important step toward low-cost, Earth-abundant, and environmentally friendly thermoelectrics.

7.
Adv Sci (Weinh) ; 5(9): 1800626, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30250801

RESUMO

Thermoelectric materials that can directly convert heat to electrical energy offer a viable solution for reducing the usage of fossil energy by harvesting waste heat resources. Higher manganese silicide (HMS) is a naturally abundant, eco-friendly, and low-cost p-type thermoelectric semiconductor with high power factor (PF); however, its figure of merit (ZT) is limited by intrinsically high thermal conductivity (κ). For effectively enhancing the thermoelectric performance of HMS and avoiding the use of expensive or toxic elements, such as Re, Te, or Pb, a green p-type MnS with high Seebeck coefficient (S) and low κ is incorporated into the HMS matrix to form MnS/HMS composites. The incorporation of MnS leads to a 31% reduction of κ and a 10% increase of S. The ZT value increases by ≈48% from 0.40 to 0.59 at 823 K. Correspondingly, performance/price ratio is first proposed to evaluate the practical value of thermoelectric materials, which is higher than those of the vast majority of current thermoelectric materials. This study provides an overview of enhancing ZT of HMS and reducing costs, which may also be applicable to other thermoelectric materials.

8.
Adv Mater ; : e1802016, 2018 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-29984538

RESUMO

Microstructure engineering is an effective strategy to reduce lattice thermal conductivity (κl ) and enhance the thermoelectric figure of merit (zT). Through a new process based on melt-centrifugation to squeeze out excess eutectic liquid, microstructure modulation is realized to manipulate the formation of dislocations and clean grain boundaries, resulting in a porous network with a platelet structure. In this way, phonon transport is strongly disrupted by a combination of porosity, pore surfaces/junctions, grain boundaries, and lattice dislocations. These collectively result in a ≈60% reduction of κl compared to zone melted ingot, while the charge carriers remain relatively mobile across the liquid-fused grains. This porous material displays a zT value of 1.2, which is higher than fully dense conventional zone melted ingots and hot pressed (Bi,Sb)2 Te3 alloys. A segmented leg of melt-centrifuged Bi0.5 Sb1.5 Te3 and Bi0.3 Sb1.7 Te3 could produce a high device ZT exceeding 1.0 over the whole temperature range of 323-523 K and an efficiency up to 9%. The present work demonstrates a method for synthesizing high-efficiency porous thermoelectric materials through an unconventional melt-centrifugation technique.

9.
Asian Pac J Trop Med ; 10(11): 1090-1094, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29203108

RESUMO

OBJECTIVE: To observe the effect of taurine on immune function in mice with T-cell lymphoma during chemotherapy. METHODS: A total of 40 C57BL/6 mice were selected and randomly divided into 4 groups, namely model group, chemotherapy group, taurine group and chemotherapy + taurine group, each containing 10 mice. Hypodermic injection was adopted to inoculate EL-4 cells in order to establish model of T-cell lymphoma. When the tumor achieved the size of 1 cm3, intervention treatments were given to the groups respectively. Mice in model group received 0.2 mL of normal saline which was intraperitoneally injected on Days 1, 8 and 15 with 3 weeks as a cycle; mice in chemotherapy group were administered with 80 mg/kg body weight of gemcitabine which was also intraperitoneally injected on Days 1, 8 and 15 with 3 weeks as a cycle; mice in taurine group were administered with 80 mg/kg body weight of taurine intraperitoneally injected daily for consecutive 8 d; mice in chemotherapy + taurine group were treated in the same manner as the mice in taurine group and chemotherapy group. Five mice were sacrificed at 2 and 3 weeks after intervention respectively, and the tumor tissues were collected and weighted after removal of auxiliary tissue, then the tumor inhibition rate was calculated. The thymus and spleen of mice sacrificed at 3 weeks after intervention were collected and weighted, and thymus and spleen indexes were calculated. Enzyme linked immunosorbent assay was used to detect the serum levels of IL-4, IL-10, IL-12 and IFN-γ in mice of each group. RESULTS: The tumor weights in chemotherapy group, taurine group and chemotherapy + taurine group after 2 and 3 weeks of treatment were significantly lower than that in model group (P < 0.05); the tumor weight in chemotherapy + taurine group after 2 and 3 weeks of treatment was significantly lower than that in chemotherapy group (P < 0.05); the tumor inhibition rate in chemotherapy + taurine group was significantly higher than that in chemotherapy group and taurine group (P < 0.05); the thymus and spleen indexes in taurine group and chemotherapy + taurine group were significantly higher than those in chemotherapy group and model group (P < 0.05); the thymus and spleen indexes in chemotherapy group were significantly lower than those in model group (P < 0.05); after 3 weeks of treatment, the serum levels of IL-4, IL-12 and IFN-γ in chemotherapy group, taurine group and chemotherapy + taurine group were significantly lower than those in model group (P < 0.05); the IL-4 level in taurine group and chemotherapy + taurine group was significantly lower than that in chemotherapy group (P < 0.05); the serum level of IL-10 in chemotherapy group and chemotherapy + taurine group was significantly higher than that in model group and taurine group (P < 0.05); the serum level of IFN-γ in taurine group and chemotherapy + taurine group was significantly lower than that in model group and chemotherapy group (P < 0.05); after treatment of 3 weeks, the serum levels of IL-4 and IL-10 in chemotherapy group, taurine group and chemotherapy + taurine group were significantly lower than those in model group (P < 0.05), and IL-12 level was significantly higher than that in model group (P < 0.05); the level of IFN-γ in taurine group and chemotherapy + taurine group was significantly higher than that in model group (P < 0.05), while the level of IFN-γ in chemotherapy group was significantly lower than that in the other 3 groups (P < 0.05). CONCLUSIONS: Taurine can effectively enhance the immune function of mice with T-cell lymphoma during chemotherapy, reduce the toxicity of chemotherapy.

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