Background:Very low-protein(VLP)diets negatively impact calcium(Ca)metabolism and absorption.The objective of this study was to investigate the effect of supplemental branched-chain amino acids(BCAA)and limiting amino...Background:Very low-protein(VLP)diets negatively impact calcium(Ca)metabolism and absorption.The objective of this study was to investigate the effect of supplemental branched-chain amino acids(BCAA)and limiting amino acids(LAA)on Ca digestibility,absorption and reabsorption in pigs fed with VLP diets.Forty-eight piglets were assigned to six treatments:positive control(PC),negative control(NC),and NC containing LAA 25%,LAA 50%,LAA+BCAA 25%(LB25)and LAA+BCAA 50%(LB50)more than recommendations.Results:Relative to PC or NC,LB25 and LB50 had higher digestibility of Ca and plasma Ca and phosphorus(P),but lower plasma vitamin D3.LB50 tended to increase vitamin D receptor transcript and protein in the gut,but decreased mRNA or protein abundance of parathyroid hormone 1 receptor(PTH1R),calbindin 1(CALB1),cytochrome P450 family 27 subfamily B member 1 and occludin in small intestine.LB50 increased the transcript of cytochrome P450 family 24 subfamily A member 1 and PTH1R but decreased the transcript of transient receptor potential cation channel subfamily V member 5,CALB1 and solute carrier family 17 member 4 in kidney.Conclusion:Overall,BCAA increased Ca digestibility through regulating the transcellular and paracellular Ca absorption in the gut and reabsorption in kidney during protein restriction.展开更多
BACKGROUND Conservative treatments have been reported to diminish or resolve clinical symptoms of lumbar intervertebral disc herniation(LIDH)within a few weeks.CASE SUMMARY Computed tomography and magnetic resonance i...BACKGROUND Conservative treatments have been reported to diminish or resolve clinical symptoms of lumbar intervertebral disc herniation(LIDH)within a few weeks.CASE SUMMARY Computed tomography and magnetic resonance imaging(MRI)of the lumbar region of a 25-yearold male diagnosed with LIDH showed prolapse of the L5/S2 disc.The disc extended 1.0 cm beyond the vertebral edge and hung along the posterior vertebral edge.The patient elected a conservative treatment regimen that included traditional Chinese medicine(TCM),acupuncture,and massage.During a follow-up period of more than 12 mo,good improvement in pain was reported without complications.MRI of the lumbar region after 12 mo showed obvious reabsorption of the herniation.CONCLUSION A conservative treatment regimen of TCM,acupuncture,and massage promoted reabsorption of a prolapsed disc.展开更多
Reabsorption is one of the most fundamental optical phenomena,but it has rarely been considered in spectroscopy-based composition analysis for organic semiconductors.Here,we take four state-of-the-art organic solar ce...Reabsorption is one of the most fundamental optical phenomena,but it has rarely been considered in spectroscopy-based composition analysis for organic semiconductors.Here,we take four state-of-the-art organic solar cell(OSC)materials as examples,and systematically investigate the influence of reabsorption on photoluminescence emission and excitation spectra by both experimental studies and optical simulations.We find that the overlap between absorption and emission spectra of these OSC materials is strong enough for them to be affected by the reabsorption effect,and the effect becomes more obvious between different species in the multi-components systems.Moreover,three features of the reabsorption effect and the reabsorption strength are identified,with which we have successfully analyzed the composition in a range of OSC materials in both solution and solid-state films.Our work not only provides an important understanding of the largely overlooked feature of reabsorption in the widely used spectroscopic techniques but also offers an effective toolbox for the composition analysis of organic semiconductors.展开更多
For the flame spread over thermally thin combustibles in an atmosphere, if the atmosphere cannot emit and absorb the thermal radiation (e.g. for atmosphere of O2-N2), the conductive heat transfer from the flame to the...For the flame spread over thermally thin combustibles in an atmosphere, if the atmosphere cannot emit and absorb the thermal radiation (e.g. for atmosphere of O2-N2), the conductive heat transfer from the flame to the fuel surface dominates the flame spread at lower ambient atmosphere. As the ambient pressure increases, the flame spread rate increases, and the radiant heat transfer from the flame to the fuel surface gradually becomes the dominant driving force for the flame spread. In contrast, if the atmosphere is able to emit and absorb the thermal radiation (e.g. for atmosphere of O2-CO2), at lower pressure, the heat transfer from flame to the fuel surface is enhanced by the radiation reabsorption of the atmosphere at the leading edge of the flame, and both conduction and thermal radiation play important roles in the mechanism of flame spread. With the increase in ambient pressure, the oxygen diffuses more quickly from ambient atmosphere into the flame, the chemical reaction in the flame is enhanced, and the flame spread rate increases. When the ambient pressure is greater than a critical value, the thermal radiation from the flame to the solid surface is hampered by the radiation reabsorption of ambient atmosphere with the further increase in ambient pressure. As a result, with the increase in ambient pressure, the flame spread rate decreases and the heat conduction gradually dominates the flame spread over the fuel surface.展开更多
The expression of calcium epithelium TRPV5, alcium binding protein Calbindin-D28k and Na＋/Ca2＋ exchanger NCX1 was detected in renal distal convoluted tubule, and their effects on urine calcium reabsorption and the p...The expression of calcium epithelium TRPV5, alcium binding protein Calbindin-D28k and Na＋/Ca2＋ exchanger NCX1 was detected in renal distal convoluted tubule, and their effects on urine calcium reabsorption and the possible pathogenic mechanism in idiopathic hypercalciuria （IH） were investigated. Genetic hypercalciuric stone-forming （GHS） rats were chosen as animal models to study urine calcium reabsorption and IH. The cognate female and male rats that had maximal urine calcium were matched to breed next generation. Twelve GHS rats and 12 normal control （NC） SD rats were selected. Western blot and real time quantitative PCR were used to detect the protein and gene expression of TRPV5, Calbindin-D28k and NCX1 respectively. The expression levels of TRPV5 protein and mRNA in GHS rats were significantly lower than in NC rats （P〈0.05）. Western blot revealed that the expression levels of Calbindin-D28k in GHS rats and NC rats were 0.49±0.02 and 0.20±0.01 respectively, with the difference being significant between them （P〈0.05）. By using real time quantitative PCR, it was found that there was no significant difference in Calbindin-28k mRNA expression levels between GHS rats and NC rats （P〉0.05）. There was no significant differ- ence in the NCX1 expression between GHS rats and NC rats （P〉0.05）. It was suggested that TRPV5 and Calbindin-D28k might play an important role in urine calcium reabsorption and IH, but they dif- ferently contributed to the pathogenesis： The down-regulation of TRPV5 decreases urine calcium reabsorption, directly leading to loss of the urine calcium and resulting in hypercalciuria, and the increased Calbindin-D28k expression could relieve, neutralize and decrease intracellular Ca2＋ concentration to maintain calcium balance. NCX1 is not the key protein in urine calcium reabsorption.展开更多
OBJECTIVE Eurycoma longifolia is a tropical medicinal plant belonging to Simaroubaceae distributed in South East Asia.The aim of this study is to explore the effect and mechanism of E.longifolia stem 70%ethanol extrac...OBJECTIVE Eurycoma longifolia is a tropical medicinal plant belonging to Simaroubaceae distributed in South East Asia.The aim of this study is to explore the effect and mechanism of E.longifolia stem 70%ethanol extract(EL)and its active com⁃poundson uric acid excretion.METHODS Potassium oxonate(PO)induced hyperuricemia rats and adenine-PO induced hyperuricemia mouse model were used to evaluate the effects of EL.Ultra Performance Liquid Chromatography was used to determine the levels of plasma or serum uric acid and creatinine.Hematoxylin-eosin staining was applied to observe kidney pathological changes,Western blot⁃ting was applied to detect protein expression levels of uric acid transporters.Effects of constituents on urate uptake were tested in hU⁃RAT1-expressing HEK293T cells.RESULTS EL significantly reduced serum and plasma uric acid levels at dosages of 100,200 and 400 mg·kg^-1 in hyperuricemia rats and mice,and increased the clearance rate of uric acid and creatinine,improved therenal pathological injury.The protein expression levels of urate reabsorption transporter 1(URAT1)and glucose transporter 9 were down-regulated while sodium-dependent phosphate transporter 1 and ATP-binding cassette transporter G2 were up-regulated in the kidney after EL treat⁃ment.The diterpenes(50μmol·L^-1)isolated from EL showed inhibitory effects on urate uptake in hURAT1-expressing HEK293T cells,and the effect of eurycomanol was further confirmed in vivo.CONCLUSION EL significantly reduced blood uric acid levels and prevented pathological changes of kidney in PO induced hyperuricemia animal model,improved renal urate transports.We partly clarified the mechanism was related to suppressing effect of URAT1 by diterpene in EL.This study is the first to demonstrate that EL plays a role in hyperuricemia by promoting renal uric acid excretion.展开更多
Insulin is an important hormone that affects various metabolic processes,including kidney function.Impairment in insulin's action leads to insulin resistance in the target tissue.Besides defects in post-receptor i...Insulin is an important hormone that affects various metabolic processes,including kidney function.Impairment in insulin's action leads to insulin resistance in the target tissue.Besides defects in post-receptor insulin signaling,impairment at the receptor level could significantly affect insulin sensitivity of the target tissue.The kidney is a known target of insulin;however,whether the kidney develops "insulin resistance" is debatable.Regulation of the insulin receptor(IR) expression and its function is very well studied in major metabolic tissues like liver,skeletal muscles,and adipose tissue.The physiological relevance of IRs in the kidney has recently begun to be clarified.The credit goes to studies that showed a wide distribution of IR throughout the nephron segments and their reduced expression in the insulin resistance state.Moreover,altered renal and systemic metabolism observed in mice with targeted deletion of the IR from various epithelial cells of the kidney has strengthened this proposition.In this review,we recapitulate the crucial findings from literature that have expanded our knowledge regarding the significance of the renal IR in normal-and insulin-resistance states.展开更多
Absorption, excitation and emission spectra as well as decay time measurements at 10, 77, and 300 K were perfumed for Gd3Sc2Ga3O12 garnet single-crystal doped with Cr^3＋ and Nd^3＋ ions. Strong reabsorption of Cr3＋ ...Absorption, excitation and emission spectra as well as decay time measurements at 10, 77, and 300 K were perfumed for Gd3Sc2Ga3O12 garnet single-crystal doped with Cr^3＋ and Nd^3＋ ions. Strong reabsorption of Cr3＋ emission by Nd3＋ absorption lines was ob- served. The assignments of f-f and d-d transitions were proposed. The broad emission band of chromium ions is an indication that weak/intermediate crystal field strength is present at the Cr3＋ site.展开更多
Oncogenic osteomalacia (OOM) is an uncommon metabolic and bone disease caused by fibroblast growth factor 23 (FGF23), a phosphaturic factor produced by phosphaturic mesenchymal tumors (mixed connective tissue variant,...Oncogenic osteomalacia (OOM) is an uncommon metabolic and bone disease caused by fibroblast growth factor 23 (FGF23), a phosphaturic factor produced by phosphaturic mesenchymal tumors (mixed connective tissue variant, PMTMCTV) characterized by phosphate leakage from kidneys and subsequent hypophosphatemia. In this paper, we present the case of a patient, 42-year-old woman affected by left side limp and pain involving lumbar spine, pelvis and hip joints, referred to the Rheumatology Department of our Hospital for the treatment of a suspected sero-negative spondilo-arthritis. During hospitalization patient began an immuno-suppressive therapy with TNF-alpha inhibitors associated with Pamidornate, Indometacin, Esomeprazole and vitamin D3. Nevertheless pain did not decrease and a new examination found a worst hypophosphatemia (1 mg/dl) with normal Ca and PTH’s plasma values. During the same check-up a painful bulge on the anterior part of the right knee was observed and the Magnetic Resonance Imaging scan revealed an ovular solid lesion in the soft tissue closed to the upper part of the patella. Histological analysis identified the lesion as a PMTMCTV. After surgical removal patient got complete recovery. We will discuss about diagnostic evaluation, differential diagnosis and treatment.展开更多
In this editorial,we discussed the article published in the recent issue of the World Journal of Diabetes.To understand the effect of mizagliflozin on kidney injury induced by diabetes,we focused on the mechanisms by ...In this editorial,we discussed the article published in the recent issue of the World Journal of Diabetes.To understand the effect of mizagliflozin on kidney injury induced by diabetes,we focused on the mechanisms by which high glucose triggers oxidative stress and contributes to kidney injury in diabetes.The high level of unmetabolized glucose reaching the kidney triggers glucose reabsorption by renal tubules,which elevates the cellular glucose level of renal cells.High glucose induces lactate dehydrogenase overexpression and thus shifts glucose metabolism,which causes mitochondrial dysfunction.Mitochondria generate approximately 90%of the reactive oxygen species in cells,whose dysfunction further alters glucose metabolism and enhances reactive oxygen species generation.Oxidative stress stimulates proinflammatory factor production and kidney inflammatory injury.Mizagliflozin decreases glucose reabsorption and thus ameliorates diabetes-induced kidney injury.展开更多
Perovskite nanocrystal(PNC)solids are promising materials for optoelectronic applications.Recent studies have shown that exciton diffusion in PNC solids occurs via alternate exciton hopping(EH)and photon recycling(PR)...Perovskite nanocrystal(PNC)solids are promising materials for optoelectronic applications.Recent studies have shown that exciton diffusion in PNC solids occurs via alternate exciton hopping(EH)and photon recycling(PR).The energy disorder induced by the size distribution is a common factor in PNC solids,and the impact of this energy disorder on the exciton diffusion remains unclear.Here,we investigated the exciton diffusion in CsPbBr3 NC solids with a Gaussian size distribution of 11.2±6.8 nm via steady and time-resolved photoluminescence(PL)spectroscopy with multiple detection bands in transmission mode.Our results indicated that exciton diffusion was controlled by a downhill transfer among the different energy sites through the disordered energy landscape,as confirmed by the accompanying low-temperature PL analysis.A detailed examination revealed that the acceptor distribution in tandem with the reabsorption coefficient determined the contribution of EH and PR to exciton transfer between different energy sites.Consequently,the exciton diffusion mechanism varied in PNC solids of different thicknesses:in a thin solid with a thickness of several hundred nanometers,the exciton transfer was dominated by efficient EH and PR from the high-energy sites to the lower-energy sites;in a few-micrometer-thick solid,transfer from the medium-energy sites toward the lower-energy sites also became prominent and occurred mainly through PR.These findings enhance the understanding of the vital role that the acceptor distribution plays in the exciton diffusion process in PNC solids,providing important insights for optoelectronic applications based on PNC solids.Our work also exploits the use of commonly available tools for in-depth exciton diffusion studies,which reveals the interior diffusion information that is usually hidden in surface sensitive PL imaging methods.展开更多
Background:In the last two decades,progress in cytogenetic and genome research has enabled investigators to unravel the underlying molecular mechanisms of inherited tubulopathies such as Bartter's and Gitelman'...Background:In the last two decades,progress in cytogenetic and genome research has enabled investigators to unravel the underlying molecular mechanisms of inherited tubulopathies such as Bartter's and Gitelman's syndromes and helped physicians to better understand not only these two pathologic entities but also renal pathophysiology and salt sensitive hypertension.Data sources:Articles collected from PubMed and open access journals included original articles,research articles,and comprehensive reviews.They were evaluated by the authors with an special emphasis on originality and up to date information about molecular pathophysiology.Results:Bartter's and Gitelman's syndromes are two different inherited salt loosing tubulopathies.They are characterized by various inability of distal nephron to reabsorb sodium chloride with resultant extarcellular volume contraction and increased activity of the renin angiotensin aldosterone system.Hypokalemic metabolic alkalosis is a common feature of these two forms of tubulopathies.Hypercalciuria characterizes the majority of Bartter's syndrome,and hypomagnesemia with hypocalciuria characterizes Gitelman's syndrome.Low blood pressure is a common feature among patients who suffered from these tubulopathies.Bartter's syndromes encompass a heterogeneous group of ion channels defects localized at the thick ascending limp of Henle's loop with resultant loss of function of sodium-potassium-2 chloride cotransporter.These defects result in the impairment of the countercurrent multiplication system of the kidney as well as calcium,potassium and acid base disturbances which in the majority of cases are proved lethal especially in the antenatal and/or immediate postnatal life period.The underlying pathology in Gitelman's syndrome is defined to the distal convoluted tubule and is related to loss of function of the sodium-chloride cotransporter.The results of this defect encompass the inability of extracellular volume homeostasis,magnesium and potassium conservation,and acid base disturbances which are generally mild and in the majority of cases are not life-threatening.Conclusions:Recent advances in molecular pathophysiology of Bartter's and Gitelman's syndromes have helped physicians to better understand the underlying mechanisms of these pathologic entities which remain obscure.Data collected from experiments among genetically manipulated animals enable us to better understand the pathophysiology of mammalian kidney and the underlying mechanisms of salt sensitive hypertension and to lay a foundation for the future development of new drugs,especially diuretics and antihypertensive drugs.展开更多
Increasing the concentration of single-wall carbon nanotubes(SWCNTs)is an effective method for enhancing their luminescence intensity.However,an increase in the concentration of SWCNTs would inevitably increase their ...Increasing the concentration of single-wall carbon nanotubes(SWCNTs)is an effective method for enhancing their luminescence intensity.However,an increase in the concentration of SWCNTs would inevitably increase their reabsorption effect,degrading their luminescence efficiency.Herein,we systematically investigated variations in the photoluminescence(PL)intensity of(6,5)single-chirality SWCNTs while increasing their concentration.The results show that the PL intensity first increased to a maximum and then decreased with increasing concentration.Numerical analysis indicates that the concentration boundary corresponding to the maximum PL intensity was strongly dependent on the ratio of the optical absorbances of the SWCNTs at their excitation and emission wavelengths.According to this,statistical analysis by experimentally measuring the optical absorption spectra of 18 kinds of single-chirality SWCNTs shows that the concentration boundaries of SWCNTs were dependent upon their Types and diameters.The concentration boundary of Type I SWCNTs was higher than that of Type II SWCNTs,and the concentration boundaries of both Types increased with increasing diameter.These results provide important guidance for spectral characterization and applications in bioimaging and photoelectronic devices.展开更多
Background There are limited numbers of studies focusing on renal efects of coronavirus disease 2019(COVID-19)infection and proximal tubular dysfunction in children with COVID-19 infections.The purpose of this study w...Background There are limited numbers of studies focusing on renal efects of coronavirus disease 2019(COVID-19)infection and proximal tubular dysfunction in children with COVID-19 infections.The purpose of this study was to evaluate the functions of the proximal tubule in hospitalized children with confrmed acute COVID-19.Methods The children who were hospitalized for confrmed COVID-19 were included in this prospective descriptive analysis.The presence of at least two of the following four abnormalities was used to diagnose proximal tubule injury:abnormal tubular reabsorption of phosphate,normoglycemic glycosuria,hyperuricosuria,and proteinuria.Results A total of 115 patients were included in the study.About a third of the individuals had elevated blood creatinine levels or proteinuria.In addition,abnormal renal tubular phosphate loss measured by renal tubular phosphate loss was found in 10(8.7%)patients,as was hyperuricosuria in 28.6%.As a result,total proximal tubular dysfunction was found in 24(20.9%)patients.Conclusions One in every fve children with acute COVID-19 infections had proximal tubular dysfunction,according to our data.Although,the rate of proximal tubular dysfunction was lower than in adults,it should be noted.The recovery of proximal tubular function in children with COVID-19 should be followed.展开更多
In this study,Gd^(3+)and Bi^(3+)ions act to redshift the emission band to orange region,and to enhance significantly the maximum emission of YAG:Ce^(3+).On account that size mismatch between the host and the doped Gd^...In this study,Gd^(3+)and Bi^(3+)ions act to redshift the emission band to orange region,and to enhance significantly the maximum emission of YAG:Ce^(3+).On account that size mismatch between the host and the doped Gd^(3+)ion,the crystal structure turns soft,and the emission spectra are not tuned from 540 to 570 nm but decreased the emission intensity.Accordingly,an effective way to increase emission intensity is to introduce Bi^(3+)ion into the YAG:Ce^(3+),Gd^(3+)phosphors.Experimental results show partial overlapping between the emission band of Bi^(3+)ion and the excitation band of Ce^(3+)ion,indicating that the energy transfer from Bi^(3+)to Ce^(3+)ions exists in the(Y_(1.94)Ce_(0.06)Gd)Al_(5)O_(12):Bi^(3+)phosphor.Bi^(3+)ion can serve as the activator to provide energy for Ce^(3+)ion via cross relaxation phenomenon.Therefore,the(Y_(1.94)Ce_(0.06)Gd)Al_(5)O_(12):Bi^(3+)phosphor could have potential applications in warm white LEDs.展开更多
基金funded by Animal Health and Production and Animal Products:Improved Nutritional Performance,Growth,and Lactation of Animals,grant no. 2021–67016-33399/project accession no. 1024334Hatch project accession no. 1012889 from the USDA National Institute of Food and Agriculture (NIFA)
文摘Background:Very low-protein(VLP)diets negatively impact calcium(Ca)metabolism and absorption.The objective of this study was to investigate the effect of supplemental branched-chain amino acids(BCAA)and limiting amino acids(LAA)on Ca digestibility,absorption and reabsorption in pigs fed with VLP diets.Forty-eight piglets were assigned to six treatments:positive control(PC),negative control(NC),and NC containing LAA 25%,LAA 50%,LAA+BCAA 25%(LB25)and LAA+BCAA 50%(LB50)more than recommendations.Results:Relative to PC or NC,LB25 and LB50 had higher digestibility of Ca and plasma Ca and phosphorus(P),but lower plasma vitamin D3.LB50 tended to increase vitamin D receptor transcript and protein in the gut,but decreased mRNA or protein abundance of parathyroid hormone 1 receptor(PTH1R),calbindin 1(CALB1),cytochrome P450 family 27 subfamily B member 1 and occludin in small intestine.LB50 increased the transcript of cytochrome P450 family 24 subfamily A member 1 and PTH1R but decreased the transcript of transient receptor potential cation channel subfamily V member 5,CALB1 and solute carrier family 17 member 4 in kidney.Conclusion:Overall,BCAA increased Ca digestibility through regulating the transcellular and paracellular Ca absorption in the gut and reabsorption in kidney during protein restriction.
基金Supported by National Nature Science Foundation of China,No.82004495Natural Science Foundation of Shandong Province,China,No.ZR2020QH318+1 种基金The 69th batch of a grant from China Postdoctoral Foundation,No.2021M691985Taishan Scholars Young Experts Program,China,No.tsqn202211349.
文摘BACKGROUND Conservative treatments have been reported to diminish or resolve clinical symptoms of lumbar intervertebral disc herniation(LIDH)within a few weeks.CASE SUMMARY Computed tomography and magnetic resonance imaging(MRI)of the lumbar region of a 25-yearold male diagnosed with LIDH showed prolapse of the L5/S2 disc.The disc extended 1.0 cm beyond the vertebral edge and hung along the posterior vertebral edge.The patient elected a conservative treatment regimen that included traditional Chinese medicine(TCM),acupuncture,and massage.During a follow-up period of more than 12 mo,good improvement in pain was reported without complications.MRI of the lumbar region after 12 mo showed obvious reabsorption of the herniation.CONCLUSION A conservative treatment regimen of TCM,acupuncture,and massage promoted reabsorption of a prolapsed disc.
基金supported by the Knut and Alice Wallenberg Foundation(Dnr.KAW 2019.0082)the Swedish Government Strategic Research Area in Materials Science on Functional Materials at Link?ping University(Faculty Grant SFO-Mat-LiU No.2009-00971)+3 种基金the Swedish Energy Agency Energimyndigheten(No.48758-1)the National Academic Infrastructure for Super-computing in Sweden(NAISS)supported by the National Natural Science Foundation of China(No.52120105005)the financial support from the Swedish Research Council(No.2021-04674)。
文摘Reabsorption is one of the most fundamental optical phenomena,but it has rarely been considered in spectroscopy-based composition analysis for organic semiconductors.Here,we take four state-of-the-art organic solar cell(OSC)materials as examples,and systematically investigate the influence of reabsorption on photoluminescence emission and excitation spectra by both experimental studies and optical simulations.We find that the overlap between absorption and emission spectra of these OSC materials is strong enough for them to be affected by the reabsorption effect,and the effect becomes more obvious between different species in the multi-components systems.Moreover,three features of the reabsorption effect and the reabsorption strength are identified,with which we have successfully analyzed the composition in a range of OSC materials in both solution and solid-state films.Our work not only provides an important understanding of the largely overlooked feature of reabsorption in the widely used spectroscopic techniques but also offers an effective toolbox for the composition analysis of organic semiconductors.
基金This work was supported by the National Natural Science Foundation of China(Grant No.59986004).
文摘For the flame spread over thermally thin combustibles in an atmosphere, if the atmosphere cannot emit and absorb the thermal radiation (e.g. for atmosphere of O2-N2), the conductive heat transfer from the flame to the fuel surface dominates the flame spread at lower ambient atmosphere. As the ambient pressure increases, the flame spread rate increases, and the radiant heat transfer from the flame to the fuel surface gradually becomes the dominant driving force for the flame spread. In contrast, if the atmosphere is able to emit and absorb the thermal radiation (e.g. for atmosphere of O2-CO2), at lower pressure, the heat transfer from flame to the fuel surface is enhanced by the radiation reabsorption of the atmosphere at the leading edge of the flame, and both conduction and thermal radiation play important roles in the mechanism of flame spread. With the increase in ambient pressure, the oxygen diffuses more quickly from ambient atmosphere into the flame, the chemical reaction in the flame is enhanced, and the flame spread rate increases. When the ambient pressure is greater than a critical value, the thermal radiation from the flame to the solid surface is hampered by the radiation reabsorption of ambient atmosphere with the further increase in ambient pressure. As a result, with the increase in ambient pressure, the flame spread rate decreases and the heat conduction gradually dominates the flame spread over the fuel surface.
文摘The expression of calcium epithelium TRPV5, alcium binding protein Calbindin-D28k and Na＋/Ca2＋ exchanger NCX1 was detected in renal distal convoluted tubule, and their effects on urine calcium reabsorption and the possible pathogenic mechanism in idiopathic hypercalciuria （IH） were investigated. Genetic hypercalciuric stone-forming （GHS） rats were chosen as animal models to study urine calcium reabsorption and IH. The cognate female and male rats that had maximal urine calcium were matched to breed next generation. Twelve GHS rats and 12 normal control （NC） SD rats were selected. Western blot and real time quantitative PCR were used to detect the protein and gene expression of TRPV5, Calbindin-D28k and NCX1 respectively. The expression levels of TRPV5 protein and mRNA in GHS rats were significantly lower than in NC rats （P〈0.05）. Western blot revealed that the expression levels of Calbindin-D28k in GHS rats and NC rats were 0.49±0.02 and 0.20±0.01 respectively, with the difference being significant between them （P〈0.05）. By using real time quantitative PCR, it was found that there was no significant difference in Calbindin-28k mRNA expression levels between GHS rats and NC rats （P〉0.05）. There was no significant differ- ence in the NCX1 expression between GHS rats and NC rats （P〉0.05）. It was suggested that TRPV5 and Calbindin-D28k might play an important role in urine calcium reabsorption and IH, but they dif- ferently contributed to the pathogenesis： The down-regulation of TRPV5 decreases urine calcium reabsorption, directly leading to loss of the urine calcium and resulting in hypercalciuria, and the increased Calbindin-D28k expression could relieve, neutralize and decrease intracellular Ca2＋ concentration to maintain calcium balance. NCX1 is not the key protein in urine calcium reabsorption.
文摘OBJECTIVE Eurycoma longifolia is a tropical medicinal plant belonging to Simaroubaceae distributed in South East Asia.The aim of this study is to explore the effect and mechanism of E.longifolia stem 70%ethanol extract(EL)and its active com⁃poundson uric acid excretion.METHODS Potassium oxonate(PO)induced hyperuricemia rats and adenine-PO induced hyperuricemia mouse model were used to evaluate the effects of EL.Ultra Performance Liquid Chromatography was used to determine the levels of plasma or serum uric acid and creatinine.Hematoxylin-eosin staining was applied to observe kidney pathological changes,Western blot⁃ting was applied to detect protein expression levels of uric acid transporters.Effects of constituents on urate uptake were tested in hU⁃RAT1-expressing HEK293T cells.RESULTS EL significantly reduced serum and plasma uric acid levels at dosages of 100,200 and 400 mg·kg^-1 in hyperuricemia rats and mice,and increased the clearance rate of uric acid and creatinine,improved therenal pathological injury.The protein expression levels of urate reabsorption transporter 1(URAT1)and glucose transporter 9 were down-regulated while sodium-dependent phosphate transporter 1 and ATP-binding cassette transporter G2 were up-regulated in the kidney after EL treat⁃ment.The diterpenes(50μmol·L^-1)isolated from EL showed inhibitory effects on urate uptake in hURAT1-expressing HEK293T cells,and the effect of eurycomanol was further confirmed in vivo.CONCLUSION EL significantly reduced blood uric acid levels and prevented pathological changes of kidney in PO induced hyperuricemia animal model,improved renal urate transports.We partly clarified the mechanism was related to suppressing effect of URAT1 by diterpene in EL.This study is the first to demonstrate that EL plays a role in hyperuricemia by promoting renal uric acid excretion.
基金Supported by Department of Biotechnology,Ministry of Science and Technology,India and Ramalingaswami Grant,No.BT/HRD/35/02/17/2008(to Tiwari S)Fellowships from Council of Scientific and Industrial Research,India,No.09/590/(0159)/2016-EMR-1(to Sharma R)and No.09/590/(0156)/2014-EMR-1(to Kumari M)
文摘Insulin is an important hormone that affects various metabolic processes,including kidney function.Impairment in insulin's action leads to insulin resistance in the target tissue.Besides defects in post-receptor insulin signaling,impairment at the receptor level could significantly affect insulin sensitivity of the target tissue.The kidney is a known target of insulin;however,whether the kidney develops "insulin resistance" is debatable.Regulation of the insulin receptor(IR) expression and its function is very well studied in major metabolic tissues like liver,skeletal muscles,and adipose tissue.The physiological relevance of IRs in the kidney has recently begun to be clarified.The credit goes to studies that showed a wide distribution of IR throughout the nephron segments and their reduced expression in the insulin resistance state.Moreover,altered renal and systemic metabolism observed in mice with targeted deletion of the IR from various epithelial cells of the kidney has strengthened this proposition.In this review,we recapitulate the crucial findings from literature that have expanded our knowledge regarding the significance of the renal IR in normal-and insulin-resistance states.
基金supported by Ministry of Science and Higher Education (N N507 372335)
文摘Absorption, excitation and emission spectra as well as decay time measurements at 10, 77, and 300 K were perfumed for Gd3Sc2Ga3O12 garnet single-crystal doped with Cr^3＋ and Nd^3＋ ions. Strong reabsorption of Cr3＋ emission by Nd3＋ absorption lines was ob- served. The assignments of f-f and d-d transitions were proposed. The broad emission band of chromium ions is an indication that weak/intermediate crystal field strength is present at the Cr3＋ site.
文摘Oncogenic osteomalacia (OOM) is an uncommon metabolic and bone disease caused by fibroblast growth factor 23 (FGF23), a phosphaturic factor produced by phosphaturic mesenchymal tumors (mixed connective tissue variant, PMTMCTV) characterized by phosphate leakage from kidneys and subsequent hypophosphatemia. In this paper, we present the case of a patient, 42-year-old woman affected by left side limp and pain involving lumbar spine, pelvis and hip joints, referred to the Rheumatology Department of our Hospital for the treatment of a suspected sero-negative spondilo-arthritis. During hospitalization patient began an immuno-suppressive therapy with TNF-alpha inhibitors associated with Pamidornate, Indometacin, Esomeprazole and vitamin D3. Nevertheless pain did not decrease and a new examination found a worst hypophosphatemia (1 mg/dl) with normal Ca and PTH’s plasma values. During the same check-up a painful bulge on the anterior part of the right knee was observed and the Magnetic Resonance Imaging scan revealed an ovular solid lesion in the soft tissue closed to the upper part of the patella. Histological analysis identified the lesion as a PMTMCTV. After surgical removal patient got complete recovery. We will discuss about diagnostic evaluation, differential diagnosis and treatment.
基金Supported by The Basic Research Project of Wenzhou Municipal Science and Technology Bureau,No.Y20240008The Medical Health Science and Technology Project of Zhejiang Provincial Health Commission,No.2024KY138The Key Laboratory of School of Laboratory Medicine and Life Sciences,Wenzhou Medical University of China,No.JS2023003。
文摘In this editorial,we discussed the article published in the recent issue of the World Journal of Diabetes.To understand the effect of mizagliflozin on kidney injury induced by diabetes,we focused on the mechanisms by which high glucose triggers oxidative stress and contributes to kidney injury in diabetes.The high level of unmetabolized glucose reaching the kidney triggers glucose reabsorption by renal tubules,which elevates the cellular glucose level of renal cells.High glucose induces lactate dehydrogenase overexpression and thus shifts glucose metabolism,which causes mitochondrial dysfunction.Mitochondria generate approximately 90%of the reactive oxygen species in cells,whose dysfunction further alters glucose metabolism and enhances reactive oxygen species generation.Oxidative stress stimulates proinflammatory factor production and kidney inflammatory injury.Mizagliflozin decreases glucose reabsorption and thus ameliorates diabetes-induced kidney injury.
基金financially supported by Shenzhen Fundamental Research Program(JCYJ20200109142425294)the National Natural Science Foundation of China(62034009 and 62104266)the Shenzhen Science and Technology Innovation Program(2022A006)。
文摘Perovskite nanocrystal(PNC)solids are promising materials for optoelectronic applications.Recent studies have shown that exciton diffusion in PNC solids occurs via alternate exciton hopping(EH)and photon recycling(PR).The energy disorder induced by the size distribution is a common factor in PNC solids,and the impact of this energy disorder on the exciton diffusion remains unclear.Here,we investigated the exciton diffusion in CsPbBr3 NC solids with a Gaussian size distribution of 11.2±6.8 nm via steady and time-resolved photoluminescence(PL)spectroscopy with multiple detection bands in transmission mode.Our results indicated that exciton diffusion was controlled by a downhill transfer among the different energy sites through the disordered energy landscape,as confirmed by the accompanying low-temperature PL analysis.A detailed examination revealed that the acceptor distribution in tandem with the reabsorption coefficient determined the contribution of EH and PR to exciton transfer between different energy sites.Consequently,the exciton diffusion mechanism varied in PNC solids of different thicknesses:in a thin solid with a thickness of several hundred nanometers,the exciton transfer was dominated by efficient EH and PR from the high-energy sites to the lower-energy sites;in a few-micrometer-thick solid,transfer from the medium-energy sites toward the lower-energy sites also became prominent and occurred mainly through PR.These findings enhance the understanding of the vital role that the acceptor distribution plays in the exciton diffusion process in PNC solids,providing important insights for optoelectronic applications based on PNC solids.Our work also exploits the use of commonly available tools for in-depth exciton diffusion studies,which reveals the interior diffusion information that is usually hidden in surface sensitive PL imaging methods.
文摘Background:In the last two decades,progress in cytogenetic and genome research has enabled investigators to unravel the underlying molecular mechanisms of inherited tubulopathies such as Bartter's and Gitelman's syndromes and helped physicians to better understand not only these two pathologic entities but also renal pathophysiology and salt sensitive hypertension.Data sources:Articles collected from PubMed and open access journals included original articles,research articles,and comprehensive reviews.They were evaluated by the authors with an special emphasis on originality and up to date information about molecular pathophysiology.Results:Bartter's and Gitelman's syndromes are two different inherited salt loosing tubulopathies.They are characterized by various inability of distal nephron to reabsorb sodium chloride with resultant extarcellular volume contraction and increased activity of the renin angiotensin aldosterone system.Hypokalemic metabolic alkalosis is a common feature of these two forms of tubulopathies.Hypercalciuria characterizes the majority of Bartter's syndrome,and hypomagnesemia with hypocalciuria characterizes Gitelman's syndrome.Low blood pressure is a common feature among patients who suffered from these tubulopathies.Bartter's syndromes encompass a heterogeneous group of ion channels defects localized at the thick ascending limp of Henle's loop with resultant loss of function of sodium-potassium-2 chloride cotransporter.These defects result in the impairment of the countercurrent multiplication system of the kidney as well as calcium,potassium and acid base disturbances which in the majority of cases are proved lethal especially in the antenatal and/or immediate postnatal life period.The underlying pathology in Gitelman's syndrome is defined to the distal convoluted tubule and is related to loss of function of the sodium-chloride cotransporter.The results of this defect encompass the inability of extracellular volume homeostasis,magnesium and potassium conservation,and acid base disturbances which are generally mild and in the majority of cases are not life-threatening.Conclusions:Recent advances in molecular pathophysiology of Bartter's and Gitelman's syndromes have helped physicians to better understand the underlying mechanisms of these pathologic entities which remain obscure.Data collected from experiments among genetically manipulated animals enable us to better understand the pathophysiology of mammalian kidney and the underlying mechanisms of salt sensitive hypertension and to lay a foundation for the future development of new drugs,especially diuretics and antihypertensive drugs.
基金supported by the National Key Research and Development Program of China(Nos.2020YFA0714700 and 2018YFA0208402)the National Natural Science Foundation of China(Nos.51820105002,11634014,51872320,and 52172060)+2 种基金the Strategic Priority Research Program of Chinese Academy of Sciences(No.XDB33030100)the Key Research Program of Frontier Sciences,Chinese Academy of Sciences(No.QYZDBSSW-SYS028)the Youth Innovation Promotion Association of Chinese Academy of Sciences(No.2020005).
文摘Increasing the concentration of single-wall carbon nanotubes(SWCNTs)is an effective method for enhancing their luminescence intensity.However,an increase in the concentration of SWCNTs would inevitably increase their reabsorption effect,degrading their luminescence efficiency.Herein,we systematically investigated variations in the photoluminescence(PL)intensity of(6,5)single-chirality SWCNTs while increasing their concentration.The results show that the PL intensity first increased to a maximum and then decreased with increasing concentration.Numerical analysis indicates that the concentration boundary corresponding to the maximum PL intensity was strongly dependent on the ratio of the optical absorbances of the SWCNTs at their excitation and emission wavelengths.According to this,statistical analysis by experimentally measuring the optical absorption spectra of 18 kinds of single-chirality SWCNTs shows that the concentration boundaries of SWCNTs were dependent upon their Types and diameters.The concentration boundary of Type I SWCNTs was higher than that of Type II SWCNTs,and the concentration boundaries of both Types increased with increasing diameter.These results provide important guidance for spectral characterization and applications in bioimaging and photoelectronic devices.
文摘Background There are limited numbers of studies focusing on renal efects of coronavirus disease 2019(COVID-19)infection and proximal tubular dysfunction in children with COVID-19 infections.The purpose of this study was to evaluate the functions of the proximal tubule in hospitalized children with confrmed acute COVID-19.Methods The children who were hospitalized for confrmed COVID-19 were included in this prospective descriptive analysis.The presence of at least two of the following four abnormalities was used to diagnose proximal tubule injury:abnormal tubular reabsorption of phosphate,normoglycemic glycosuria,hyperuricosuria,and proteinuria.Results A total of 115 patients were included in the study.About a third of the individuals had elevated blood creatinine levels or proteinuria.In addition,abnormal renal tubular phosphate loss measured by renal tubular phosphate loss was found in 10(8.7%)patients,as was hyperuricosuria in 28.6%.As a result,total proximal tubular dysfunction was found in 24(20.9%)patients.Conclusions One in every fve children with acute COVID-19 infections had proximal tubular dysfunction,according to our data.Although,the rate of proximal tubular dysfunction was lower than in adults,it should be noted.The recovery of proximal tubular function in children with COVID-19 should be followed.
文摘In this study,Gd^(3+)and Bi^(3+)ions act to redshift the emission band to orange region,and to enhance significantly the maximum emission of YAG:Ce^(3+).On account that size mismatch between the host and the doped Gd^(3+)ion,the crystal structure turns soft,and the emission spectra are not tuned from 540 to 570 nm but decreased the emission intensity.Accordingly,an effective way to increase emission intensity is to introduce Bi^(3+)ion into the YAG:Ce^(3+),Gd^(3+)phosphors.Experimental results show partial overlapping between the emission band of Bi^(3+)ion and the excitation band of Ce^(3+)ion,indicating that the energy transfer from Bi^(3+)to Ce^(3+)ions exists in the(Y_(1.94)Ce_(0.06)Gd)Al_(5)O_(12):Bi^(3+)phosphor.Bi^(3+)ion can serve as the activator to provide energy for Ce^(3+)ion via cross relaxation phenomenon.Therefore,the(Y_(1.94)Ce_(0.06)Gd)Al_(5)O_(12):Bi^(3+)phosphor could have potential applications in warm white LEDs.
