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1.
Sensors (Basel) ; 24(9)2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38732952

RESUMO

Orthogonal chirp division multiplexing (OCDM) offers a promising modulation technology for shallow water underwater acoustic (UWA) communication systems due to multipath fading resistance and Doppler resistance. To handle the various channel distortions and interferences, obtaining accurate channel state information is vital for robust and efficient shallow water UWA communication. In recent years, deep learning has attracted widespread attention in the communication field, providing a new way to improve the performance of physical layer communication systems. In this paper, the pilot-based channel estimation is transformed into a matrix completion problem, which is mathematically equivalent to the image super-resolution problem arising in the field of image processing. Simulation results show that the deep learning-based method can improve the channel distortion, outperforming the equalization performed by traditional estimator, the performance of Bit Error Rate is improved by 2.5 dB compared to the MMSE method in OCDM system. At the 7.5 to 20 dB region, it achieves better bit error rate performance than OFDM systems, and the bit error rate is reduced by approximately 53% compared to OFDM when the SNR value is 20, which is very useful in shallow water UWA channels with multipath extension and severe time-varying characteristics.

2.
Carbohydr Polym ; 335: 122075, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38616096

RESUMO

Polyethylene oxide (PEO) solid electrolytes, acknowledged for their safety advantages over liquid counterparts, confront inherent challenges, including low ionic conductivity, restricted lithium ion migration, and mechanical fragility, notably pronounced in lithium­sulfur batteries due to the polysulfide shuttling phenomenon. To address these limitations, we integrate a quaternary ammonium cation-modified cellulose (QACC) nanofiber, electrospun with cellulose acetate (CA) from recycled cigarette filters, into the PEO electrolyte matrix. The nitrogen atom within the quaternary ammonium group exhibits a pronounced affinity for polysulfide compounds, effectively curtailing polysulfide migration. Concurrently, Lewis acid-base interactions between quaternary ammonium groups and lithium salt anions facilitate the release of additional Li+, achieving a lithium-ion transference number 1.5 times higher than its pure PEO counterpart. Furthermore, the introduction of a larger trifluoromethanesulfonimide (TFSI) group on the QACC macromolecule (TFSI-QACC) disrupts the ordered arrangement of PEO macromolecules, resulting in a noteworthy enhancement in ionic conductivity, reaching 2.07 × 10-4 S cm-1 at 60 °C, thus addressing the challenge of low PEO electrolyte conductivity. Moreover, the nanofiber enhances the mechanical strength of the PEO electrolyte from 0.49 to 7.50 MPa, mitigating safety concerns related to lithium dendrites puncturing the electrolyte. Consequently, the composite PEO demonstrates exemplary performance in lithium symmetrical batteries, enduring 500 h of continuous operation and completing 100 cycles at both room and elevated temperatures. This integrated approach, transitioning from waste to wealth, adeptly addresses a spectrum of challenges in the efficiency of solid-state electrolytes, holding considerable promise for advancing lithium­sulfur battery technology.

3.
Biomed Pharmacother ; 162: 114694, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37054540

RESUMO

Diabetic nephropathy (DN) is a common microvascular complication of both type 1 and type 2 diabetes mellitus and often advances to end-stage renal disease. Oxidative stress plays an important role in the pathogenesis and progress of DN. Hydrogen sulfide (H2S) is considered as a promising candidate for the management of DN. But the antioxidant effects of H2S in DN have not been fully studied. In mouse model induced by high-fat diet and streptozotocin, GYY4137, a H2S donor, ameliorated albuminuria at weeks 6 & 8 and decreased serum creatinine at week 8, but not hyperglycemia. Renal nitrotyrosine and urinary 8-isoprostane were reduced along with the suppressed levels of renal laminin and kidney-injury-molecule 1. Renal NADPH oxidase (NOX) 2 was lower but heme oxygenase (HO) 2, paraoxonase (PON) 1, PON2 were higher in DN+GYY than DN group. NOX1, NOX4, HO1, superoxide dismutases 1-3 were similar between groups. Except for a rise at HO2, all the affected enzymes were unchanged in mRNA levels. The affected reactive-oxygen-species (ROS) enzymes were mainly located in the renal sodium-hydrogen-exchanger positive proximal tubules with similar distribution but changed immunofluorence in GYY4137 treated DN mice. Kidney morphological alterations in DN mice under light and electrical-microscopes were also improved by GYY4137. Thus, exogenous H2S administration may improve the renal oxidative damage in DN by reducing ROS production and enhancing ROS cleavage in kidney via the affected enzymes. This study may shed a light on therapeutic applications in diabetic nephropathy with H2S donors in the future.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Nefropatias Diabéticas , Camundongos , Animais , Nefropatias Diabéticas/tratamento farmacológico , Espécies Reativas de Oxigênio/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Rim/patologia , Estresse Oxidativo
4.
FASEB J ; 37(4): e22834, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36961378

RESUMO

The kidney regulates blood pressure through salt/water reabsorption affected by tubular sodium transporters. Expanding our prior research on placental cluster of differentiation 81 (CD81), this study explores the interaction of renal CD81 with sodium transporters in preeclampsia (PE). Effects of renal CD81 with sodium transporters were determined in lipopolysaccharide (LPS)-induced PE rats and immortalized mouse renal distal convoluted tubule cells. Urinary exosomal CD81, sodium potassium 2 chloride cotransporter (NKCC2), and sodium chloride cotransporter (NCC) were measured in PE patients. LPS-PE rats had hypertension from gestational days (GD) 6 to 18 and proteinuria from GD9 to GD18. Urinary CD81 in both groups tented to rise during pregnancy. Renal CD81, not sodium transporters, was higher in LPS-PE than controls on GD14. On GD18, LPS-PE rats exhibited higher CD81 in kidneys and urine exosomes, higher renal total and phosphorylated renal NKCC2 and NCC with elevated mRNAs, and lower ubiquitinated NCC than controls. CD81 was co-immunoprecipitated with NKCC2 or NCC in kidney homogenates and co-immunostained with NKCC2 or NCC in apical membranes of renal tubules. In plasma membrane fractions, LPS-PE rats had greater amounts of CD81, NKCC2, and NCC than controls with enhanced co-immunoprecipitations of CD81 with NKCC2 or NCC. In renal distal convoluted tubule cells, silencing CD81 with siRNA inhibited NCC and prevented LPS-induced NCC elevation. Further, PE patients had higher CD81 in original urines, urine exosomes and higher NKCC2 and NCC in urine exosomes than controls. Thus, the upregulation of renal CD81 on NKCC2 and NCC may contribute to the sustained hypertension observed in LPS-PE model. Urine CD81 with NKCC2 and NCC may be used as biomarkers for PE.


Assuntos
Hipertensão , Pré-Eclâmpsia , Gravidez , Camundongos , Humanos , Ratos , Feminino , Animais , Simportadores de Cloreto de Sódio-Potássio/metabolismo , Simportadores de Cloreto de Sódio/genética , Simportadores de Cloreto de Sódio/metabolismo , Lipopolissacarídeos/toxicidade , Lipopolissacarídeos/metabolismo , Cloretos/metabolismo , Pré-Eclâmpsia/induzido quimicamente , Pré-Eclâmpsia/metabolismo , Membro 1 da Família 12 de Carreador de Soluto/metabolismo , Placenta/metabolismo , Túbulos Renais Distais/metabolismo , Hipertensão/metabolismo , Sódio/metabolismo , Potássio/metabolismo , Tetraspanina 28/metabolismo
5.
Biomed Pharmacother ; 161: 114484, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36921530

RESUMO

A low-salt diet may activate the renin-angiotensin-aldosterone system (RAAS) and is often applied simultaneously with RAAS inhibitors, especially for treatment of proteinuric nephritis. To explore the effect of a low-salt diet combined with angiotensin receptor blockers (ARB) on kidney function, the proteinuric nephritis model was induced by single intravenous injection of doxorubicin, and then the SD rats were administrated with candesartan intraperitoneal injection and fed with different salt diets. Rats with low-salt plus candesartan, not either alone, experienced acute kidney injury (AKI) at day 7 and could not self-restore when extending the experiment time from 7 days to 21 days, unless switching low-salt to normal-salt. Among three nitric oxide synthetases (NOS), endothelial NOS (eNOS) was obviously elevated and PI3K-Akt-eNOS signal pathway was activated. NG-Nitro-L-Arginine Methyl Ester (L-NAME), an eNOS inhibitor, reversed the decreased blood pressure and recovered the kidney dysfunction induced by low-salt with candesartan. The increased TUNEL-positive cells, Bax/Bcl-2 and cleaved-caspase3 protein abundance was ameliorated by L-NAME in vivo. In vitro, sodium nitroprusside, a nitric oxide donor, can also increase Bax/Bcl-2 and cleaved-caspase3 protein level in HK-2 cell. Thus, low-salt diet combined with candesartan in nephritis rats led to AKI, and the mechanism involved the increase of eNOS/NO, which linked to the decrease of blood pressure and the increase of apoptosis. This study provides practical guidance for salt intake in cases of RAS inhibitor usage clinically.


Assuntos
Injúria Renal Aguda , Nefrite , Ratos , Animais , Rim , NG-Nitroarginina Metil Éster/farmacologia , Dieta Hipossódica , Óxido Nítrico/metabolismo , Antagonistas de Receptores de Angiotensina/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteína X Associada a bcl-2/metabolismo , Ratos Sprague-Dawley , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Pressão Sanguínea , Óxido Nítrico Sintase/metabolismo , Cloreto de Sódio , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/metabolismo , Nefrite/metabolismo
6.
Sci Data ; 10(1): 107, 2023 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-36823205

RESUMO

The irregular shape of mineral particles directly affects the angle of repose, bulk density and flow-properties, and the interaction behaviour between the particles and a contact surface. This paper presents a dataset of spatial data and shape parameters collected from 37 gangue particles and 135 anthracite coal particles, which come from the Shangzhuang Coal Mine. The particle surface models were obtained by a Wiiboox white light raster 3D scanner and Reeyee software. To obtain the scanning surface, each particle was scanned 8 times in different axial rotation directions. The final scanning model was obtained by stacking two scanning surfaces, and the shape parameters, such as length ratio, flatness ratio, and Zingg index, were obtained. This dataset is particularly useful for researchers and engineers who want to investigate the shape of coal and gangue particles or who want to test or benchmark measurement methods concerning the three-dimensional morphology of particles.

7.
Diagnostics (Basel) ; 12(11)2022 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-36359477

RESUMO

The diagnosis of acute kidney injury (AKI) traditionally depends on the serum creatinine (Scr) and urine output, which lack sufficient sensitivity and specificity. Using urinary exosomes as a biomarker has unique advantages. To assess whether urinary exosomal Na+/H+ exchanger isoform 3 (NHE3) protein could serve as a biomarker of AKI, we constructed four AKI rat models: cisplatin (7.5 mg/kg) injected intraperitoneally (IP), furosemide (20 mg/kg, IP) with a low-NaCl (0.03%) diet, a low-NaCl (0.03%) diet with candesartan (1 mg/kg, IP) and bilateral ischemia and reperfusion (I/R) injury for 40 min. Additionally, we assessed six sepsis-associated AKI patients and six healthy volunteers. Urinary exosomes were extracted by ultracentrifugation, and the NHE3 protein abundance was tested by immunoblotting for all the AKI rats and human subjects. The isolated cup-shaped particles with an average diameter of 70 nm and enrichment in CD63 were identified as exosomes. NHE3 abundance was six times higher in exosomes than in the whole urine. In cisplatin-induced AKI rats, urinary exosomal NHE3 was increased on day 2, one day earlier than the increases in Scr and blood urea nitrogen (BUN). In additional rats, urinary exosomal NHE3 decreased along with the decline in Scr after EPO pretreatment. In volume-depletion AKI induced by furosemide injection with a low-NaCl diet, the urinary exosomal NHE3 expression was higher than that in the control. Under a low-NaCl diet with candesartan-related AKI, the urinary exosomal NHE3 was elevated on day 5, earlier than Scr. In I/R-injury AKI, the urinary exosomal NHE3 was also raised compared with that in the control. In humans, the urinary exosomal NHE3 level was also elevated in sepsis-associated AKI patients in comparison with that in the healthy volunteers. The urinary exosomal NHE3 was increased in multiple AKI; it may be used as a diagnostic biomarker of AKI.

8.
Small ; 18(31): e2202834, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35808966

RESUMO

Chemoradiotherapy (CRT) is the most accepted treatment for locally advanced pancreatic ductal adenocarcinoma (PDAC) and can significantly improve the R0 resection rate. However, there are few long-term survivors after CRT. Although some polymer nanoparticles have shown potential in alleviating the dose-limiting toxicity and assisting the chemotherapy of PDAC, there are few efficient nanosensitizers (NS) available for CRT of this malignancy, especially in the context of its hypoxic nature. Herein, based on the biological features of PDAC, a γ-glutamyl transpeptidase (GGT)/glutathione (GSH)/hypoxia triple-responsive prodrug NS to overcome the biological barrier and microenvironmental limitations confronted by CRT in PDAC is developed. Due to triple-responsiveness, deep tumor penetration, GSH/hypoxia-responsive drug release/activation, and hypoxia-induced chemoradio-sensitization can be simultaneously achieved with this NS. As a result, tumor shrinkage after CRT with this NS can be observed in both subcutaneous and orthotopic PDAC models, foreshadowing its potential in clinical neoadjuvant CRT.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Pró-Fármacos , Carcinoma Ductal Pancreático/tratamento farmacológico , Quimiorradioterapia , Humanos , Hipóxia/tratamento farmacológico , Neoplasias Pancreáticas/tratamento farmacológico , Pró-Fármacos/uso terapêutico , Neoplasias Pancreáticas
9.
Small ; 18(28): e2202651, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35723170

RESUMO

Exploring a scalable strategy to fabricate a multifunctional separator is of great significance to overcome the challenges of lithium polysulfides (LiPSs) and dendritic growth in lithium-sulfur batteries (LSBs). Herein, a binder-free Janus separator is constructed by interfacial engineering. At the cathode interface, an ultra-thin covalent triazine piperazine film containing tailorable micropores and adsorption sites is decorated on polyacrylonitrile (PAN) membrane by in situ interfacial polymerization, building a triple barrier for LiPSs. The combination of steric hindrance and chemical adsorption reduces LiPS's migration by 81.85%. Meanwhile, at the anode interface, a fast-ionic conductor Li6.4 La3 Zr1.4 Ta0.6 O12  (LLZTO) is created on the surface of PAN nanofiber by magnetron sputtering to suppress dendrite growth. Even though there is no binder between the ceramic layer and the fibrous separator, sputtering creates an inter-embedded structure that ensures no depowering after cycling. Furthermore, the PAN-based separator displays a high temperature tolerance of 180 °C. Consequently, the cell delivers a high capacity of 1287.9 mAh g-1 at 0.5 C and stable cycling performance with an ultra-low capacity decay rate of 0.059% per cycle over 500 cycles. This work provides a scalable strategy for functionalizing separators to tackle the challenges in LSBs, which is binder-free, stripping-free, and essentially thickening-free.

10.
Entropy (Basel) ; 24(2)2022 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-35205510

RESUMO

The resonant modes generated from the modern Chladni experiment are systematically confirmed to intimately correspond to the maximum entropy states obtained from the inhomogeneous Helmholtz equation for the square and equilateral triangle plates. To investigate the origin of maximum entropy states, the inhomogeneous Helmholtz equation is modified to consider the point interaction coming from the driving oscillator. The coupling strength associated with the point interaction is characterized by a dimensionless factor α. The δ potential of the point interaction is numerically modelled by a truncated basis with an upper index N. The asymptotic behavior for the upper index N is thoroughly explored to verify that the coupling strength of α = 1.0 can make the theoretical resonant modes agree excellently with the maximum entropy states as N→∞. It is further authenticated that nearly the same resonant modes can be obtained by using a larger coupling strength α when a smaller upper index N is exploited in the calculation.

11.
Kidney Dis (Basel) ; 5: 1-10, 2021 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-34192120

RESUMO

BACKGROUND: The COVID-19 pandemic has brought increased focus on hydroxychloroquine (HCQ), as doctors, the medical community, and policymakers around the world attempt to understand how the risks of HCQ weigh against unknown benefits. We aim to evaluate the effects of HCQ on cardiac conduction, thus contributing to the global understanding of implications of HCQ use. METHODS: We reviewed 717 cases of nonmalaria patients treated with HCQ (302) or without HCQ (415) in our hospital from 2008 to 2019, analyzed the cardiac conduction recorded by electrocardiogram (122 vs. 180) including heart rate (HR), PR, and corrected-QT (QTc) intervals, and explored the relationship of cardiac conduction with age, HCQ dosage, HCQ duration, sex, and primary diseases in HCQ users. RESULTS: The all-cause mortality is similar between HCQ and non-HCQ groups (4.0 vs. 4.3%, p = 0.85). Patients aged 45 years or older, not younger ones, have lower HR (80.1 ± 1.7 vs. 85.7 ± 1.8 bpm, p = 0.03) but longer PR (163 ± 3.4 vs. 146.6 ± 4.2 ms, p = 0.003) and QTc (417.8 ± 3.8 vs. 407.7 ± 2.7 ms, p = 0.03) in HCQ than those in non-HCQ. The age in the HCQ group is positively correlated with PR (R = 0.31, p < 0.01) and QTc (R = 0.34, p < 0.01) but not HR. HR, PR, and QTc are not related to HCQ dosage (0.1-0.6 g/day), HCQ duration (0.2-126 months), sex, primary diseases, and repeated exams. CONCLUSION: Age is the most important risk factor of HCQ on cardiac conduction in nonmalaria patients. Electrocardiogram monitoring is suggested in aged patients due to the effects of HCQ on HR, PR, and QTc.

12.
J Nutr Sci Vitaminol (Tokyo) ; 67(2): 84-90, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33952739

RESUMO

Few studies have been performed to investigate the effect of vitamin D supplementation and T2DM in type 2 diabetic animal models. The present study aimed to explore the relationship between early 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] and the incidence of T2DM and determine whether early 1,25(OH)2D3 supplementation was associated with inflammation in KK-Ay mice. The KK-Ay mice were divided into 4 vitamin D treatment groups, the low-dose vitamin D supplementation group (VDS-L, 1.5 µg/kg 1,25(OH)2D3), moderate-dose vitamin D supplementation group (VDS-M, 3.0 µg/kg 1,25(OH)2D3), high-dose vitamin D supplementation group (VDS-H, 6.0 µg/kg 1,25(OH)2D3) and the model control group (MC). C57BL/6J mice were used as the controls. The treatment period lasted for 9 wk. During this treatment period, fasting blood glucose (FBG) level of the mice was measured on a weekly basis. The levels of lipid profile, insulin and inflammation biomarkers were determined after 9 wk of 1,25(OH)2D3 intragastric gavage. After 9 wk of 1,25(OH)2D3 intragastric gavage, FBG level was significantly decreased in the vitamin D treatment groups compared with the MC group. The number of T2DM incidence in the VDS-L group (n=7), VDS-M group (n=5) and VDS-H group (n=3) was lower than those in the MC group (n=10) on week 9. Moreover, serum C-reactive protein (CRP) and interleukin-6 (IL-6) in the vitamin D treatment groups were significantly suppressed by 1,25(OH)2D3 administration compared with the MC group. Early 1,25(OH)2D3 supplementation could effectively lower the incidence of T2DM via ameliorating inflammation in KK-Ay mice.


Assuntos
Diabetes Mellitus Tipo 2 , Animais , Diabetes Mellitus Tipo 2/tratamento farmacológico , Suplementos Nutricionais , Incidência , Inflamação/tratamento farmacológico , Inflamação/prevenção & controle , Camundongos , Camundongos Endogâmicos C57BL , Vitamina D/análogos & derivados
13.
FASEB J ; 35(5): e21576, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33864412

RESUMO

Exogenous hydrogen sulfide (H2 S) protects kidneys from diabetic injuries in animal models. In order to explore the role of endogenous H2 S in diabetic nephropathy, we determined the renal H2S producing enzymes in vivo and in vitro. In diabetic mice, H2 S levels in blood and kidney were decreased while cystathionine ß-synthase (CBS), mainly located in mouse renal proximal convoluted tubules (PCT), was reduced selectively. In cultured mouse PCT cells treated with high glucose, CBS protein and activity was reduced while ubiquitinated CBS was increased, which was abolished by a proteasome inhibitor MG132 at 1 hour; high glucose drove CBS colocalized with proteasome 26S subunit ATPase6, indicating an involvement of ubiquitination proteasome degradation. At 48 hours, high glucose also selectively decreased CBS protein, concentration-dependently, but increased the ubiquitination of CBS; silence of CBS by siRNA increased nitrotyrosine, a marker for protein oxidative injury. Nitrotyrosine was also increased by high glucose treatments. The increases of nitrotyrosine either by cbs-siRNA or by glucose were restored by GYY4137, indicating that the H2 S donor may protect kidney from oxidative injury induced by CBS deficiency. In diabetic kidneys, ubiquitinated CBS and nitrotyrosine were increased but restored by GYY4137. The treatment also ameliorated albuminuria and renal morphologic changes in diabetic mice. Our findings suggest that high glucose induces reduction of renal CBS protein and activity in vivo and in vitro that is critical to the pathogenesis of diabetic kidney disease.


Assuntos
Cistationina beta-Sintase/deficiência , Diabetes Mellitus Experimental/complicações , Nefropatias Diabéticas/patologia , Glucose/farmacologia , Sulfeto de Hidrogênio/metabolismo , Animais , Nefropatias Diabéticas/etiologia , Nefropatias Diabéticas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL
14.
J Environ Sci (China) ; 102: 363-372, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33637261

RESUMO

The pollution characteristics of surfactant substances in fine particles (PM2.5) in spring were studied in the Beibu Gulf Region of China, 68 samples of PM2.5 were collected at Weizhou Island in Beihai City from March 12 to April 17, 2015. The Anionic Surfactant Substances (ASS) and Cationic Surfactant Substances (CSS) in the samples were analyzed using Byethyl Violet Spectrophotometry and Disulfide Blue Spectrophotometry, respectively. Combined with the data from backward trajectory simulation, the effects of air pollutants from remote transport on the pollution characteristics of surfactant substances in PM2.5 in the Beibu Gulf Region were analyzed and discussed. The results showed that the daily mean concentrations of ASS and CSS in spring in the Beibu Gulf Region were 165.20 pmol/m3 and 8.05pmol/m3, and the variation ranges were 23.21-452.55 pmol/m3 and 0.65-31.31 pmol/m3, accounting for 1.82‰ ± 1.65‰ and 0.12‰ ± 0.11‰ of the mass concentration of PM2.5, respectively. These concentrations were lower than those in comparable regions around the world. There was no clear correlation between the concentrations of ASS and CSS in PM2.5 and the mass concentrations of PM2.5. Tourism and air transport had a positive contribution on the concentrations of ASS. The concentration of surfactant substances in PM2.5 was significantly impacted by wind speed and wind direction. Atmospheric temperature, air pressure and precipitation had little effect on the concentrations of surfactant substances. Surfactant substances in PM2.5 significantly impacted visibility. Results also showed that the main sources of surfactant substances were from the southern China and Southeast Asia.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluição do Ar/análise , China , Cidades , Monitoramento Ambiental , Material Particulado/análise , Estações do Ano , Tensoativos
15.
ACS Nano ; 15(1): 781-796, 2021 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-33410660

RESUMO

Chemotherapy is one of the most commonly used clinical antitumor strategies. However, the therapy-induced proliferative burst, which always accompanies drug resistance and metastasis, has become a major obstacle during treatment. Except for some endogenous cellular or genetic mechanisms and some microenvironmental selection pressures, the intercellular connections in the tumor microenvironment (TME) are also thought to be the driving force for the acquired drug resistance and proliferative burst. Even though some pathway inhibitors or cell exempting strategies could be applied to partially avoid these unwanted communications, the complexity of the TME and the limited knowledge about those unknown detrimental connections might greatly compromise the efforts. Therefore, a more broad-spectrum strategy is urgently needed to relieve the drug-induced burst proliferation during various treatments. In this article, based on the possible discrepancies in metabolic activity between cells with different growth rates, several ester-bond-based prodrugs were synthesized. After screening, 7-ethyl-10-hyodroxycamptothecin-based prodrug nanoparticles were found to efficiently overcome the paclitaxel resistance, to selectively act on the malignantly proliferated drug-resistant cells and, furthermore, to greatly diminish the proliferative effect of common cytotoxic agents by blocking the detrimental intercellular connections. With the discriminating ability against malignant proliferating cells, the as-prepared prodrug nanomedicine exhibited significant anticancer efficacy against both drug-sensitive and drug-resistant tumor models, either by itself or by combining with highly potent nonselective chemotherapeutics. This work provides a different perspective and a possible solution for the treatment of therapy-induced burst proliferation.


Assuntos
Antineoplásicos , Nanopartículas , Pró-Fármacos , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Nanomedicina , Paclitaxel , Pró-Fármacos/farmacologia
16.
Adv Mater ; 32(43): e2004901, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32924219

RESUMO

The COVID-19 pandemic has taken a significant toll on people worldwide, and there are currently no specific antivirus drugs or vaccines. Herein it is a therapeutic based on catalase, an antioxidant enzyme that can effectively breakdown hydrogen peroxide and minimize the downstream reactive oxygen species, which are excessively produced resulting from the infection and inflammatory process, is reported. Catalase assists to regulate production of cytokines, protect oxidative injury, and repress replication of SARS-CoV-2, as demonstrated in human leukocytes and alveolar epithelial cells, and rhesus macaques, without noticeable toxicity. Such a therapeutic can be readily manufactured at low cost as a potential treatment for COVID-19.


Assuntos
Anti-Inflamatórios/uso terapêutico , Antioxidantes/uso terapêutico , Betacoronavirus/efeitos dos fármacos , Catalase/uso terapêutico , Infecções por Coronavirus/tratamento farmacológico , Pneumonia Viral/tratamento farmacológico , Animais , Anti-Inflamatórios/farmacocinética , Antioxidantes/farmacocinética , Betacoronavirus/fisiologia , COVID-19 , Catalase/farmacocinética , Linhagem Celular , Infecções por Coronavirus/metabolismo , Infecções por Coronavirus/virologia , Humanos , Leucócitos/efeitos dos fármacos , Leucócitos/metabolismo , Leucócitos/virologia , Macaca mulatta , Camundongos , Camundongos Endogâmicos BALB C , Estresse Oxidativo/efeitos dos fármacos , Pandemias , Pneumonia Viral/metabolismo , Pneumonia Viral/virologia , Alvéolos Pulmonares/efeitos dos fármacos , Alvéolos Pulmonares/metabolismo , Alvéolos Pulmonares/virologia , SARS-CoV-2 , Replicação Viral/efeitos dos fármacos
17.
J Control Release ; 326: 25-37, 2020 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-32531414

RESUMO

Cisplatin is widely used in the chemoradiotherapy (CRT) of cervical cancers. However, despite the severe systemic side effects, the therapeutic efficacy of cisplatin is often compromised by the development of drug resistance, which is closely related to the elevated intracellular thiol-containing species (especially glutathione (GSH)) and the adenosine triphosphate (ATP)-dependent glutathione S-conjugate pumps. The construction of a safe and redox-sensitive nano-sensitizer with high disulfide density and high Pt(IV) prodrug loading capacity (up to 16.50% Pt and even higher), as described herein, is a promising way to overcome the cisplatin resistance and enhance the CRT efficacy. The optimized nanoparticles (NPs) (referred to as SSCV5) with moderate Pt loading (7.62% Pt) and median size (c.a. 40 nm) was screened out and used for further biological evaluation. Compared with free cisplatin, more drugs could be transported and released inside the cisplatin resistant cells (Hela-CDDP) by SSCV5 NPs. With the synergistic effect of GSH scavenging and mitochondrial damage, SSCV5 NPs can easily reverse the cisplatin resistance. Moreover, the higher nucleus DNA binding Pt content of SSCV5 NPs not only caused the DNA damage and apoptosis of Hela-CDDP cells but also sensitized these cells to X-Ray radiation. The in vivo safety and efficacy results showed that SSCV5 NPs effectively accumulated inside tumor and inhibited the growth of cisplatin resistant xenograft models while alleviating the serious side effect associated with cisplatin (the maximum tolerated cisplatin equivalent of single injection is higher than 20 mg/kg body weight). The intervention of exogenous radiation further improved the anticancer efficacy of SSCV5 NPs and caused the shrinkage of tumor volume, thus making this safe and facile nano-sensitizer a promising route for the neoadjuvant CRT of cervical cancers.


Assuntos
Antineoplásicos , Nanopartículas , Pró-Fármacos , Neoplasias do Colo do Útero , Linhagem Celular Tumoral , Quimiorradioterapia , Cisplatino , Feminino , Humanos , Platina , Neoplasias do Colo do Útero/tratamento farmacológico
18.
Ann Nutr Metab ; 73(1): 62-73, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29945132

RESUMO

BACKGROUND/AIMS: The mechanism, by which vitamin D influences inflammatory biomarkers in type 2 diabetes mellitus (T2DM), is not very well known. Thus, a meta-analysis of randomized controlled trials was conducted to assess the effect of vitamin D supplementation on some inflammatory biomarkers in T2DM subjects. METHODS: We searched randomized controlled trials from PubMed and the Cochrane Library in October 2017 and conducted a meta-analysis to evaluate the effectiveness of vitamin D supplementation on high-sensitivity C-reactive protein (hs-CRP), tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6). Either a fixed-effects or a random-effects model was used to calculate pooled effects. RESULTS: We identified 13 studies that met our inclusion criteria. The results indicated that the vitamin D supplementation significant decreased the hs-CRP level by 0.45 µg/mL, whereas the vitamin D supplementation did not  influence the TNF-α and IL-6. Subgroup analysis showed that vitamin D significantly lowered hs-CRP by 0.34 µg/mL among trials with a daily vitamin D dose ≤4,000 IU and by 0.31 µg/mL among trials with time of vitamin D supplementation > 12 weeks. CONCLUSIONS: Vitamin D supplementation is beneficial for the reduction of hs-CRP inT2DM subjects but does not have a significant influence on TNF-α and IL-6 in T2DM subjects.


Assuntos
Diabetes Mellitus Tipo 2/sangue , Suplementos Nutricionais , Vitamina D/administração & dosagem , Biomarcadores/sangue , Proteína C-Reativa/análise , Humanos , Interleucina-6/sangue , Ensaios Clínicos Controlados Aleatórios como Assunto , Fator de Necrose Tumoral alfa/sangue , Vitaminas/administração & dosagem
19.
Nephron ; 139(3): 269-282, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29539618

RESUMO

BACKGROUND: Renal fibrosis is a common outcome of nearly all kinds of chronic kidney disease (CKD) and eventually progresses to end-stage renal disease. The identification of an optimal biomarker of renal fibrosis to replace the invasive renal biopsy will have important clinical implications. METHODS: We isolated urinary exosomes from 50 participants and examined the exosomal protein content and particle number in 38 CKD patients with different degrees of renal fibrosis and in 12 normal individuals. We examined the levels of exosomal microRNAs (miRNAs), namely, miR-200a, miR-200b, miR-200c, miR-141, miR-429, miR-29a, miR-29b, miR-29c, miR-192, and miR-21, by sorting the exosomes and comparing the levels of proximal tubular, non-proximal tubular, and total exosomal miR-200b. RESULTS: The exosome content was higher in the CKD group, but no differences were evident among the mild, moderate, and severe fibrosis groups. Among the 10 exosomal miRNAs, miR-200b was lower in the CKD group than in the normal group and decreased more significantly with fibrosis progression as well as in IgA nephropathy and diabetic kidney disease. CD13+ CD63+ exosomes constituted 18.6% of all urinary exosomes. Sorting the proximal tubular exosomes with the CD13 protein marker revealed that miR-200b in the CD13+ group was extremely low; however, the result was significantly different in the CD13- group but not in the CD13+ group. The magnitude of the decline was greater in the CD13- groups than in the non-sorted whole groups between the fibrosis and normal patients. CONCLUSIONS: Non-proximal renal tubule-derived urinary exosomal miR-200b is a biomarker of renal fibrosis. Exosomes can be used as a liquid biopsy and may replace the traditional invasive renal biopsy in the diagnosis of renal fibrosis.


Assuntos
Túbulos Renais/patologia , MicroRNAs/urina , Adulto , Biomarcadores/urina , Antígenos CD13/análise , Estudos de Casos e Controles , Creatinina/sangue , Creatinina/urina , Nefropatias Diabéticas/urina , Progressão da Doença , Exossomos/química , Feminino , Fibrose/diagnóstico , Glomerulonefrite por IGA/urina , Humanos , Túbulos Renais/metabolismo , Túbulos Renais Proximais/química , Masculino , Pessoa de Meia-Idade , Proteinúria
20.
BMC Nephrol ; 19(1): 50, 2018 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-29506482

RESUMO

BACKGROUND: C-type natriuretic peptide (CNP) is a member of the natriuretic peptide family and have been implicated to be involved in maintaining vascular homeostasis and acting as a cardiac chronotropic agent in experimental studies. However, clinical evidence of its participation in cardiovascular regulation is lacking, especially in patients with chronic kidney disease (CKD). We aimed to explore the association of circulating CNP with cardiovascular alterations in CKD. METHODS: Seventy-six subjects with CKD were recruited. Plasma CNP-22, the bioactive form of CNP in the circulation, was measured by an enzyme immunoassay. The patients also underwent several cardiovascular evaluations including measurement of blood pressure, endothelial function, heart rate variability (HRV) and pulse wave velocity. RESULTS: Mean (±standard deviation) age of the patients were 59.9 (±14.9) years and 56.6% were male. Average plasma CNP level was 790.8 ± 309.1 pg/ml. Plasma CNP level was not increased as estimated glomerular filtration rate declined. There was no significant difference of CNP between patients with or without endothelial dysfunction (with vs. without endothelial dysfunction: 844.6 ± 365.5 pg/ml vs. 738.3 ± 231.8 pg/ml, p = 0.14). Plasma CNP showed no association with blood pressure or pulse wave velocity, but was negatively associated with time-domain HRV parameters (SDNN, RMSSD, Triangular Index). The association of CNP with HRV persisted after adjustment for potential covariates. CONCLUSIONS: Our data highlights a possible link between circulating CNP and autonomic dysfunction in CKD patients. Further studies are warranted to explore the mechanisms underlying this association, as well as evaluate the ability of circulating CNP in predicting adverse cardiovascular event in CKD patients.


Assuntos
Frequência Cardíaca/fisiologia , Peptídeo Natriurético Tipo C/sangue , Insuficiência Renal Crônica/sangue , Insuficiência Renal Crônica/fisiopatologia , Idoso , Biomarcadores/sangue , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Onda de Pulso/tendências , Insuficiência Renal Crônica/diagnóstico
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