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1.
Mol Pharm ; 2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33544609

RESUMO

Renal fibrosis is the final manifestation of various chronic kidney diseases. Interstitial myofibroblasts, which are reported to highly express integrin αvß3, are the effector cells in renal fibrogenesis. Since current therapies do not efficiently target these cells, there is no effective therapeutic method for preventing or mitigating the disease. Here, we modified sterically stable PEGylated liposomes with the pentapeptide cRGDfC (RGD-Lip), which has a high affinity for αvß3, to specifically deliver drug to renal interstitial myofibroblasts. Our results showed that attaching cRGDfC to liposomes significantly increased their uptake by activated renal fibroblasts NRK-49F cells, and this effect was greatly abolished by adding excess-free cRGDfC or a knockdown of αvß3. Systemic administration of RGD-Lip gave rise to significant accumulation in a fibrotic kidney, which is ascribed to the specific recognition with integrin αvß3 on interstitial myofibroblasts. When loaded with celastrol, RGD-guided liposomes dramatically depressed the proliferation and activation of NRK-49F cells in vitro. Additionally, celastrol-loaded RGD-Lip markedly attenuated renal fibrosis, injury, and inflammation induced by unilateral ureteral obstruction (UUO) in mice, without inducing significant systemic toxicity. Thus, this liposomal system shows great promise for delivering therapeutic agents to interstitial myofibroblasts for renal fibrosis treatment with minimal side effects.

2.
Ann Palliat Med ; 2021 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-33549030

RESUMO

BACKGROUND: Radiotherapy is the cornerstone in cancer treatment, and its adverse effects have been recognized widely nowadays. In response, effective and nontoxic therapies are in demand for patients affected by radiotherapy-induced adverse effects (RIAE). As a multitude of clinical studies have suggested that acupuncture therapies seem to be potential in treating RIAE, this study aims to make a systematic review and Bayesian network meta-analysis (NMA) to evaluate effectiveness and safety of different acupuncture treatments. METHODS: A full-scale search will be performed in the following databases from inception to June, 2020: PubMed/Medline, Cochrane library, Web of Science, Ebsco, Embase, China National Knowledge Infrastructure (CNKI), Wanfang Database, VIP Database and China Biology Medicine disc (CBM). Randomized controlled trials meeting the eligible criteria based on PICOS elements will be included. The primary outcome is the response rate of RIAE or the incidence of RIAE. The secondary outcome is the incidence of adverse events directly related to acupuncture. Cochrane risk-of-bias tool (ROB 2.0) will be employed to evaluate the quality of chosen literatures. Stata, Addis and OpenBUGS will be performed to manage data. DISCUSSION: The results can provide a relatively objective evidence to assess effectiveness and safety of acupuncture therapies for each RIAE, which may be rewarding as a guiding proposal for researchers concerning RIAE. TRIAL REGISTRATION: This study has been registered at INPLASY (https://inplasy.com/) with a registration ID INPLASY202070054.

3.
Acta Pharmacol Sin ; 2021 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-33558655

RESUMO

Breast cancer resistance protein (BCRP) and P-glycoprotein (P-gp) are co-located at blood-brain barrier (BBB) cells, preventing their substrates from entering brain. Accumulating evidence demonstrates that liver failure impairs P-gp and BCRP expression and function in the brain. In the current study, we investigated how liver failure influenced the expression and function of brain BCRP and P-gp in rats subjected to bile duct ligation (BDL). The function of BCRP, P-gp and BBB integrity was assessed using distribution of prazosin, rhodamine 123 and fluorescein, respectively. We showed that BDL significantly decreased BCRP function, but increased P-gp function without affecting BBB integrity. Furthermore, we found that BDL significantly downregulated the expression of membrane BCRP and upregulated the expression of membrane P-gp protein in the cortex and hippocampus. In human cerebral microvascular endothelial cells, NH4Cl plus unconjugated bilirubin significantly decreased BCRP function and expression of membrane BCRP protein, but upregulated P-gp function and expression of membrane P-gp protein. The decreased expression of membrane BCRP protein was linked to the decreased expression of membrane radixin protein, while the increased expression of membrane P-gp protein was related to the increased location of membrane ezrin protein. Silencing ezrin impaired membrane location of P-gp, whereas silencing radixin impaired membrane location of BCRP protein. BDL rats showed the increased expression of membrane ezrin protein and decreased expression of membrane radixin protein in the brain. We conclude that BDL causes opposite effects on the expression and function of brain BCRP and P-gp, attributing to the altered expression of membrane radixin and ezrin protein, respectively, due to hyperbilirubinemia and hyperammonemia.

4.
Diabetologia ; 2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33544171

RESUMO

AIMS/HYPOTHESIS: Besides serving as a traditional inflammatory marker, C-reactive protein (CRP) is closely associated with the development of obesity, diabetes and cardiovascular diseases as a metabolic and inflammatory marker. We hypothesise that CRP protein directly participates in the regulation of energy and glucose metabolism rather than just being a surrogate marker, and that genetic deficiency of CRP will lead to resistance to obesity and insulin resistance. METHODS: Crp gene deletion was achieved by transcription activator-like effector nuclease (TALEN) technology in rats. The Crp knockout animals were placed on either a standard chow diet or a high-fat diet. Phenotypic changes in body weight, glucose metabolism, insulin sensitivity, energy expenditure and inflammation condition were examined. The central impact of CRP deficiency on leptin and insulin hypothalamic signalling, as well as glucose homeostasis, were examined via intracerebral ventricular delivery of leptin and CRP plus glucose clamp studies in the wild-type and Crp knockout rats. RESULTS: CRP deficiency led to a significant reduction in weight gain and food intake, elevated energy expenditure and improved insulin sensitivity after exposure to high-fat diet. Glucose clamp studies revealed enhanced hepatic insulin signalling and actions. Deficiency of CRP enhanced and prolonged the weight-reducing effect of central injected leptin and promoted the central and peripheral roles of leptin. By contrast, reinstatement of CRP into the hypothalamus of the knockout rats attenuated the effects of central leptin signalling on insulin sensitivity and peripheral glucose metabolism. CONCLUSIONS/INTERPRETATION: This study represents the first line of genetic evidence that CRP is not merely a surrogate blood marker for inflammation and metabolic syndromes but directly regulates energy balance, body weight, insulin sensitivity and glucose homeostasis through direct regulation of leptin's central effect and hypothalamic signalling.

5.
Plant Physiol ; 2021 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-33599732

RESUMO

Ethiopian mustard (Brassica carinata) in the Brassicaceae family possesses many excellent agronomic traits. Here, the high-quality genome sequence of B. carinata is reported. Characterization revealed a genome anchored to 17 chromosomes with a total length of 1.087 Gb and an N50 scaffold length of 60 Mb. Repetitive sequences account for approximately 634 Mb or 58.34% of the B. carinata genome. Notably, 51.91% of 97,149 genes are confined to the terminal 20% of chromosomes as a result of the expansion of repeats in pericentromeric regions. Brassica carinata shares one whole-genome triplication event with the five other species in U's triangle, a classic model of evolution and polyploidy in Brassica. Brassica carinata was deduced to have formed ∼0.047 Mya, which is slightly earlier than B. napus but later than B. juncea. Our analysis indicated that the relationship between the two subgenomes (BcaB and BcaC) is greater than that between other two tetraploid subgenomes (BjuB and BnaC) and their respective diploid parents. RNA-seq datasets and comparative genomic analysis were used to identify several key genes in pathways regulating disease resistance and glucosinolate metabolism. Further analyses revealed that genome triplication and tandem duplication played important roles in the expansion of those genes in Brassica species. With the genome sequencing of B. carinata completed, the genomes of all six Brassica species in U's triangle are now resolved. The data obtained from genome sequencing, transcriptome analysis, and comparative genomic efforts in this study provide valuable insights into the genome evolution of the six Brassica species in U's triangle.

6.
Toxicol Lett ; 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33600922

RESUMO

Triptolide (TP), an active component of Tripterygium wilfordii Hook. F, has been widely used in China for treating autoimmune and inflammatory diseases, and has also been validated by modern science and developed as a candidate anti-cancer treatment. However, liver toxicity of TP has seriously hindered its use and development, the clinical features and primary toxicological mechanism have been unclear. Considering the major target regulation mechanism of TP is the suppression of global transcription regulated by RNAPII, which is closed related with the detoxification of drugs. This paper tries to verify the synergistic liver injury and its mechanism of TP when co-administered with CYP3A4 substrate drug. The experiments showed that TP dose-dependently blocked transcriptional activation of CYP3A4 in both hPXR and hPXR-CYP3A4 reporter cell lines, lowered the mRNA and protein expression of PXR target genes such as CYP3A1, CYP2B1, and MDR1, and inhibited the functional activity of CYP3A in a time- and concentration-dependent manner in sandwich-cultured rat hepatocytes (SCRH) and female Sprague-Dawley (f-SD) rats. Furthermore, TP combined with atorvastatin (ATR), the substrate of CYP3A4, synergistically enhanced hepatotoxicity in cultured HepG2 and SCRH cells (CI is 0.38 and 0.29, respectively), as well as in f-SD rats, with higher exposure levels of both drugs. These results clearly indicate that TP inhibits PXR-mediated transcriptional activation of CYP3A4, leading to a blockade on the detoxification of itself and ATR, thereby greatly promoting liver injury. This study may implies the key cause of TP related liver injury and provides experimental data for the rational use of TP in a clinical scenario.

7.
Phytochemistry ; 184: 112680, 2021 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-33550196

RESUMO

Five undescribed abietane diterpenoids, dracocephalumoids A-E, together with six known analogues were isolated from the aqueous EtOH extract of aerial parts of Dracocephalum moldavica L.. The structures were elucidated through extensive analysis of spectroscopic data, and their absolute configurations were established by Mosher's method and time-dependent density functional theory electronic circular dichroism (TDDFT ECD) calculation. Cell-based anti-inflammatory assays displayed that dracocephalumoid A, uncinatone, trichotomone F and caryopterisoid C showed potent suppressive effects against TNF-α, IL-1ß or NO production in LPS-induced RAW 264.7 cells, with IC50 values ranging from 1.12 to 5.84 µM. The structure-activity relationship of these compounds was also discussed.

8.
Metabolism ; : 154728, 2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33581130

RESUMO

BACKGROUND & AIMS: Cholesterol gallstone disease (CGD) is a common gastrointestinal disease. Liraglutide, an analog of glucagon-like peptide 1, has been approved to treat type 2 diabetes. Clinical studies have suggested a potential role of liraglutide in CGD. METHODS: Mice were subcutaneously injected with liraglutide, then fed a lithogenic diet. Bile duct cannulation was performed to collect bile output in mice. Intestinal-specific ablation or pharmacological inhibition of farnesoid X receptor (FXR) was used to study its functions in CGD. RESULTS: Liraglutide could protect mice against CGD. Liraglutide treatment increased the biliary concentration of cholesterol, phospholipids and bile acids and thereby decreased the cholesterol saturation index. The resistance to CGD conferred by liraglutide is likely a result of increased bile acid synthesis and efficient bile acid transport. The expression of a key bile acid synthetic enzyme, Cyp7a1, was significantly increased in liraglutide-treated mice. The increased expression of Cyp7a1 resulted from a relieved suppression signal of Fgf15 from the ileum. Mechanistically, liraglutide treatment altered bile acid composition and suppressed FXR activity in the ileum. Genetic ablation or pharmacological inhibition of FXR in the intestine protected mice against CGD. More importantly, intestinal FXR was required for liraglutide-mediated regulation of hepatic expression of Cyp7a1. CONCLUSION: Liraglutide improved CGD by increasing bile acid secretion and decreasing cholesterol saturation index. Liraglutide attenuates the negative feedback inhibition of bile acids through inhibiting intestinal FXR activity. Our results suggest that liraglutide may represent a novel way for treating or preventing cholesterol gallstones in individuals with high risk of CGD.

9.
FASEB J ; 35(3): e21408, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33583107

RESUMO

Sirtuin 6 (Sirt6), a member of the Sirtuin family, has important roles in maintaining glucose and lipid metabolism. Our previous studies demonstrated that the deletion of Sirt6 in pro-opiomelanocortin (POMC)-expressing cells by the loxP-Cre system resulted in severe obesity and hepatic steatosis. However, whether overexpression of Sirt6 in hypothalamic POMC neurons could ameliorate diet-induced obesity is still unknown. Thus, we generated mice specifically overexpressing Sirt6 in hypothalamic POMC neurons (PSOE) by stereotaxic injection of Cre-dependent adeno-associated viruses into the arcuate nucleus of Pomc-Cre mice. PSOE mice showed increased adiposity and decreased energy expenditure. Furthermore, thermogenesis of BAT and lipolysis of WAT were both impaired, caused by reduced sympathetic nerve innervation and activity in adipose tissues. Mechanistically, Sirt6 overexpression decreasing STAT3 acetylation, thus lowering POMC expression in the hypothalamus underlined the observed phenotypes in PSOE mice. These results demonstrate that Sirt6 overexpression specifically in the hypothalamic POMC neurons exacerbates diet-induced obesity and metabolic disorders via the hypothalamus-adipose axis.

10.
Biomaterials ; 270: 120690, 2021 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-33561626

RESUMO

Cancer immunotherapy, particularly the inhibition of immune checkpoints with neutralizing antibodies, has revolutionized the treatment of some cancer patients. However, immune checkpoint blockade has not provided survival benefits to most patients with colorectal and ovarian cancers. This work reports the design of acid-sensitive core-shell nanoscale coordination polymer particles (NCP) comprising a carboplatin prodrug and an siRNA against PD-L1 (siPD-L1) in the core and digitoxin on the shell for tri-modality cancer therapy. Upon cellular uptake, NCP particles rapidly burst in acidic organelles to release carboplatin for apoptosis, digitoxin for inducing immunogenicity, and siPD-L1 for PD-L1 knockdown. With long blood circulation and high tumor accumulation, NCP particles efficiently suppress the growth and metastasis of syngeneic cancers through reactivating innate and adaptive immune responses. NCP particles thus provide a promising platform to synergistically combine chemotherapy and immunotherapy for the treatment of advanced and aggressive cancers.

11.
J Transl Med ; 19(1): 37, 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33472665

RESUMO

BACKGROUND: Non-small cell lung cancer (NSCLC) is a common type of lung cancer. Extracellular vehicles (EVs) are nano-sized particles containing proteins, lipids, and miRNAs secreted by various cells, which play important roles in the development of lung cancer by regulating a wide range of signaling pathways. This study focused on elucidating a potential mechanism by which EVs promote the development of NSCLC. METHODS: Expression levels of miR-744, SUV39H1, Smad9, and BMP4 in clinical tissue samples of NSCLC patients and cell lines were quantified by RT-qPCR and/or western blot analysis. The interaction between SUV39H1 and miR-744 was identified by dual-luciferase reporter assay. miR-744, SUV39H1, and BMP4 expression levels were modulated in A549 and H460 cells, in order to evaluate their effects on cell proliferation, colony formation and cell cycle. A NSCLC xenograft mouse model was used to verify the in vitro findings. NSCLC cell-derived EVs and normal bronchial epithelial cell-derived EVs were isolated and their roles in NSCLC development were evaluated in vivo and in vitro. RESULTS: miR-744 expression was lower in cancer cell-derived derived EVs than in normal lung epithelial cell-derived EVs. Reduced miR-744 expression in EVs upregulated SUV39H1 in NSCLC cells and further increased BMP4 levels to promote NSCLC development. BMP4 was upregulated in NSCLC cells upon suppression of Smad9 mediated by SUV39H1. Reduced miR-744 expression transferred from cancer cell-derived EVs into NSCLC cells enhanced cancer development. CONCLUSION: Overall, our findings unveiled a mechanism whereby miR-744 delivered by NSCLC-derived EVs upregulated SUV39H1, activating the Smad9/BMP9 axis and thus promoted cancer development.

12.
Environ Int ; 147: 106359, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33385922

RESUMO

Climate change and human activities exert a wide range of stressors on urban coastal areas. Synthetical assessment of coastal vulnerability is crucial for effective interventions and long-term planning. However, there have been few studies based on integrative analyses of ecological and physical characteristics and socioeconomic conditions in urban coastal areas. This study developed a holistic framework for assessing coastal vulnerability from three dimensions - biophysical exposure, sensitivity and adaptive capacity - and applied it to the coast of Bohai Economic Rim, an extensive and important development zone in China. A composite vulnerability index (CVI) was developed for every 1 km2 segment of the total 5627 km coastline and the areas that most prone to coastal hazards were identified by mapping the distribution patterns of the CVIs in the present and under future climate change scenarios. The CVIs show a spatial heterogeneity, with higher values concentrated along the southwestern and northeastern coasts and lower values concentrated along the southern coasts. Currently, 20% of the coastlines with approximately 350,000 people are highly vulnerable to coastal hazards. With sea-level rises under the future scenarios of the year 2100, more coastlines will be highly vulnerable, and the amount of highly-threatened population was estimated to increase by 13-24%. Among the coastal cities, Dongying was categorized as having the highest vulnerability, mainly due to poor transportation and medical services and low GDP per capita, which contribute to low adaptive capacity. Our results can benefit decision-makers by highlighting prioritized areas and identifying the most important determinants of priority, facilitating location-specific interventions for climate-change adaptation and sustainable coastal management.

14.
Br J Pharmacol ; 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33480065

RESUMO

BACKGROUND AND PURPOSE: Sodium glucose cotransporter 2 (SGLT2) inhibitor is a hypoglycemic agent that acts by increasing urinary glucose excretion and promoting enhanced usage of fat. However, the underlying mechanism is poorly understood. This study was aimed to determine the impact of canagliflozin (Cana), a selective SGLT2 inhibitor, on diet-induced obesity and the underlying mechanism. EXPERIMENTAL APPROACH: Adult C57BL/6J male mice were fed with a chow diet or high fat diet supplemented with vehicle or Cana. Whole body energy expenditure was monitored by metabolic cages; NE levels were measured by HPLC; glucose uptake was measured by PET/CT; mRNA and protein expression were measured by RT-PCR and western blotting analysis. KEY RESULTS: We showed that mice treated with Cana were resistant to high fat diet-induced obesity and its myriad metabolic consequences. Cana treatment decreased fat mass and increased energy expenditure via promoting the thermogenesis and lipolysis of adipose tissue. Mechanistically, SGLT2 inhibition by Cana elevated adipose sympathetic innervation and fat mobilization via a ß3AR-cAMP-PKA signaling pathway. Finally, we showed that Cana improved insulin resistance and hepatic steatosis in mice fed with a high fat diet. CONCLUSIONS AND IMPLICATIONS: Our results demonstrated that chronic SGLT2 inhibition increased energy consumption by promoting intra-adipose sympathetic innervation to counteract diet-induced obesity. The present study reveals a new therapeutic function for SGLT2 inhibitors in regulating energy homeostasis.

15.
Artigo em Inglês | MEDLINE | ID: mdl-33480432

RESUMO

BACKGROUND: To investigate the knowledge, attitudes and anxiety toward COVID-19 among Chinese college students studying in China and abroad. METHOD: A structured questionnaire, comprised of demographic characteristics, knowledge and attitudes toward COVID-19 and the State-Trait Anxiety Inventory (STAI), was used to collect data for 566 domestic students and 126 students studying abroad. RESULTS: Domestic students were better than students abroad in knowledge of epidemiology and manifestations. Domestic students showed a significant higher enthusiasm for voluntary services than students abroad, including medical science popularization, community services, traffic dispersion, logistics transportation and being volunteers for vaccine trials. The scores (Mean ± SD) of S-AI and T-AI among students abroad were 59.48 ± 8.63 and 54.10 ± 7.20, respectively, which were significantly higher than those of domestic students (39.46 ± 8.16 and 39.25 ± 7.72). CONCLUSIONS: Our study showed a better understanding of knowledge, more positive attitudes and less anxiety toward COVID-19 among domestic students, compared with students studying abroad. In light of this information, more attention and appropriate psychological and social intervention should be paid to college students with anxiety, especially those studying abroad.

16.
Artigo em Inglês | MEDLINE | ID: mdl-33480650

RESUMO

INTRODUCTION: The common etiology of central nervous system (CNS) complications after allogeneic hematopoietic stem cell transplantation (allo-HSCT) includes CNS infection, metabolic abnormalities, drug toxicity, cerebrovascular events, Epstein-Barr virus-associated posttransplant lymphoproliferative diseases, and hematologic CNS relapse of leukemia. Although graft-versus-host disease (GVHD) is a major complication of allo-HSCT, its CNS involvement is exceedingly rare. CASE PRESENTATION: In this report, we describe a patient who exhibited acute myeloid leukemia with t(8;21) (q22;q22) and who suddenly lost visual acuity ~1 year after receipt of allo-HSCT. Given the observation of negative cerebrospinal fluid findings, cyclosporine-related encephalopathy, intracranial hemorrhage, CNS infection, leukemia recurrence, and tumors were excluded. He was diagnosed with both CNS and pulmonary GVHD. After steroid treatment, the lesions gradually reduced in images acquired via cranial and pulmonary computed tomography. CONCLUSIONS: CNS-GVHD is a rare, serious complication of allo-HSCT that is difficult to diagnose. Biopsy and autopsy may identify the CNS as the target of GVHD in some patients. Treatment is mainly based on the use of immunosuppressive drugs, including high doses of steroids. Early diagnosis and treatment can improve disease outcome.

17.
Mol Cell Biochem ; 2021 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-33512636

RESUMO

Primary Sjögren's syndrome (pSS) is a chronic autoimmune disease that is mainly characterized as abnormal activation of B cells. It is reported that radical s-adenosyl methionine domain-containing 2 (RSAD2) is overexpressed in CD19+ B cells of pSS patients, but its role in pSS B cells remains unknown. Herein, RSAD2 expression was upregulated in CD19+ B cells of pSS patients and positively correlated with the expression of interleukin-10 (IL-10) in serum. After CD40L stimulation, knockdown of RSAD2 significantly attenuated cell viability, the production levels of immunoglobins and the expression of IL-10, while promoted cell apoptosis of pSS CD19+ B cells. Mechanistically, knockdown of RSAD2 negatively regulated nuclear factor kappa-b (NF-κb) signaling pathway. In addition, overexpression of p65 prominently alleviated the inhibitory effect of RSAD2 knockdown on proliferation, immunoglobin production and IL-10 expression in CD40L-induced CD19+ B cells. Our study indicated that silencing RSAD2 attenuated pSS B cell hyperactivity via suppressing NF-κb signaling pathway, which might provide a potential therapeutic target for pSS treatment.

18.
Kidney Int ; 2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-33417997

RESUMO

To study human idiopathic hypercalciuria we developed an animal model, genetic hypercalciuric stone-forming rats, whose pathophysiology parallels that of human idiopathic hypercalciuria. Fed the oxalate precursor, hydroxyproline, every rat in this model develops calcium oxalate stones. Using this rat model, we tested whether chlorthalidone and potassium citrate combined would reduce calcium oxalate stone formation and improve bone quality more than either agent alone. These rats (113 generation) were fed a normal calcium and phosphorus diet with hydroxyproline and divided into four groups: diets plus potassium chloride as control, potassium citrate, chlorthalidone plus potassium chloride, or potassium citrate plus chlorthalidone. Urine was collected at six, 12, and 18 weeks and kidney stone formation and bone parameters were determined. Compared to potassium chloride, potassium citrate reduced urinary calcium, chlorthalidone reduced it further and potassium citrate plus chlorthalidone even further. Potassium citrate plus chlorthalidone decreased urine oxalate compared to all other groups. There were no significant differences in calcium oxalate supersaturation in any group. Neither potassium citrate nor chlorthalidone altered stone formation. However, potassium citrate plus chlorthalidone significantly reduced stone formation. Vertebral trabecular bone increased with chlorthalidone and potassium citrate plus chlorthalidone. Cortical bone area increased with chlorthalidone but not potassium citrate or potassium citrate plus chlorthalidone. Mechanical properties of trabecular bone improved with chlorthalidone, but not with potassium citrate plus chlorthalidone. Thus in genetic hypercalciuric stone-forming rats fed a diet resulting in calcium oxalate stone formation, potassium citrate plus chlorthalidone prevented stone formation better than either agent alone. Chlorthalidone alone improved bone quality, but adding potassium citrate provided no additional benefit.

19.
Nanoscale ; 2021 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-33444426

RESUMO

Overall electrocatalytic water splitting can efficiently and sustainably produce clean hydrogen energy to alleviate the global energy crisis and environmental pollution. Two-dimensional (2D) materials with a unique band structure and surface conformation have emerged as promising electrocatalysts for the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). However, the intrinsic activities of primitive 2D materials in the catalytic process are still inferior to those of noble metal-based electrocatalysts. Surface defect engineering can modulate the electronic structure of 2D materials and induce new physicochemical properties, promoting their electrocatalytic performance. Herein, this minireview focuses on some recent developments in surface defect engineering, including the contribution of active sites, the derivation of the heterogeneous interface, and the anchoring of active substances, which provides an effective way to further optimize 2D electrocatalysts for water splitting. Furthermore, the typical morphological characteristics, catalytic activity, stability and catalytic mechanism of these 2D electrocatalysts are introduced. We believe that this minireview will help design more efficient and economical electrocatalysts for overall water splitting.

20.
Spectrochim Acta A Mol Biomol Spectrosc ; 251: 119460, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33493934

RESUMO

Dairy products are necessary components of a healthy diet for human and nowadays, liquid milk become very popular because of its convenience. The identification of a brand of liquid milk is of importance. In this study, near-infrared (NIR) spectroscopy is used for rapid and objective classification of different brands of liquid milk. Chemometric methods including extreme learning machine (ELM) and its ensemble version (EELM) are investigated and compared. A dataset containing 144 samples from 6 brands are collected for experiment. A model-independent filter algorithm, i.e., relief-based feature selection, was used for variable reduction. Principal component analysis (PCA) is used as a tool of exploratory analysis for visualizing the difference among liquid milk samples of different brands. All samples were divided into three subsets, i.e., the training set, validation set and test set, for constructing, optimizing and testing the model, respectively. The model developed by the EELM procedure achieved 100% of classification accuracy, indicating that NIR spectroscopy combined with variable reduction and the EELM algorithm is feasible for classifying the brands of liquid milk.

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