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1.
Front Immunol ; 13: 1046810, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36439173

RESUMO

As a type of metalloproteinase, matrix metalloproteinases (MMPs) can be divided into collagenase, gelatinase, stromelysins, membrane-type (MT)-MMPs and heterogeneous subgroups according to their structure and function. MMP contents in the human body are strictly regulated, and their synthesis, activation and inhibition processes should be kept in a certain balance; otherwise, this would result in the occurrence of various diseases. Rheumatoid arthritis (RA) is a known immune-mediated systemic inflammatory disease that is affected by a variety of endogenous and exogenous factors. In RA development, MMPs act as important mediators of inflammation and participate in the degradation of extracellular matrix substrates and digestion of fibrillar collagens, leading to the destruction of joint structures. Interestingly, increasing evidence has suggested that herbal medicines have many advantages in RA due to their multitarget properties. In this paper, literature was obtained through electronic databases, including the Web of Science, PubMed, Google Scholar, Springer, and CNKI (Chinese). After classification and analysis, herbal medicines were found to inhibit the inflammatory process of RA by regulating MMPs and protecting joint structures. However, further preclinical and clinical studies are needed to support this view before these herbal medicines can be developed into drugs with actual application to the disease.


Assuntos
Artrite Reumatoide , Humanos , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/metabolismo , Metaloproteinases da Matriz/metabolismo , Inflamação , Matriz Extracelular/metabolismo
2.
BMC Pharmacol Toxicol ; 23(1): 45, 2022 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-35794660

RESUMO

PURPOSE: The combination of lisinopril and amlodipine has a marked additional effect on blood pressure and fewer side effects than individual monotherapy. This study was conducted to compare the pharmacokinetic parameters and evaluate the bioequivalence between two Lisinopril/amlodipine tablets in healthy Chinese subjects. METHODS: A single center, randomized, open-label, single-dose, two-period crossover bioequivalence study was designed in healthy Chinese subjects under both fasting and fed conditions. Blood samples were collected before drug administration and at 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 24, 36, 48, 72, 96, 144, 168 h after administration. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was applied to determine the plasma concentration of lisinopril and amlodipine. Maximum concentration (Cmax) and area under the concentration-time curve (AUC) were used to evaluate bioequivalence. Adverse events were recorded. RESULTS: Ninety-two healthy subjects were enrolled, and 75 completed the study. The 90% confidence intervals (CIs) of the ratio of geometric means (GMRs) of Cmax, AUC0-t, and AUC0-∞ of lisinopril and amlodipine under both fasting and fed conditions fell within the conventional bioequivalence criteria of 0.80-1.25. A high-fat meal appeared to decrease the Cmax and AUC of lisinopril. No severe adverse events were observed. CONCLUSION: The trial demonstrated that the test and the reference lisinopril/amlodipine tablets were bioequivalent and well tolerated in Chinese people under fasting and fed conditions. TRIAL REGISTRATION: Clinical Trails.gov identifier, NCT04885660 (retrospectively registered in 13/05/ 2021).


Assuntos
Jejum , Lisinopril , Anlodipino , China , Cromatografia Líquida , Voluntários Saudáveis , Humanos , Comprimidos , Espectrometria de Massas em Tandem , Equivalência Terapêutica
3.
Reprod Domest Anim ; 57(11): 1295-1306, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35789122

RESUMO

Mongolian horses have been bred and used for labor and transport for centuries. Nevertheless, traits of testicular development in Mongolian horses have rarely been studied; particularly, studies regarding the transcriptional regulation characteristics of testicular development are lacking. In this paper, transcription specificity during testicular development in Mongolian horses is highlighted via a multispecies comparative analysis and weighted gene co-expression network analysis (WGCNA). Interestingly, the results showed that most genes were up-regulated in the testes after sexual maturity, which is a phenomenon conserved across species. Moreover, we observed nine key genes involved in regulating Mongolian horse testicular development. Notably, unique transcription signatures of testicular development in Mongolian horses are emphasized, which provides a novel insight into the mechanistic study of their testicular development.


Assuntos
Testículo , Masculino , Animais , Cavalos/genética , Fenótipo
4.
Ying Yong Sheng Tai Xue Bao ; 33(3): 720-726, 2022 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-35524524

RESUMO

Shrubs play an important role in maintaining biodiversity, stability and ecological service in grassland. Exploring the effects of enclosure on dominant shrub population can provide scientific guidance for grassland restoration and tending management. In this study, we investigated main growth characteristics and spatial distribution pattern of Artemisia ordosica population in four enclosed grasslands with duration of 0, 5, 15, and 25 years. The results showed that population density increased first and then decreased with time extension, and peaked after enclosed for 15 years, which was 3.7 times that of unenclosed plot. The crown and projected area showed opposite responses trend to that of density, which decreased by 31.7% and 52.3% after enclosed 15 years, respectively. The height decreased by 25.3% after 5 years of enclosure, and then increased gradually. Semi-variance function analysis showed that population distribution in all grasslands conformed to Gaussian model. The spatial variation decreased gradually in the early stage of enclosure, and then increased after enclosed for 15 years. Structure ratio in each plot was higher than 0.75, but nugget was relatively small, indicating that spatial autocorrelation of population was mainly affected by structural factors rather than random factors. Spatial distribution of A. ordosica population was patchy and striped. Enclosure reduced spatial variation of population at small scale. However, spatial heterogeneity and scale dependence of population enhanced after enclosed 25 years as plaque dissociating. Our findings suggest that enclosure duration is the key factor affecting plant growth and spatial distribution of dominant population in desert steppe. Long-term fencing enhances the spatial heterogeneity of dominant population. Appropriate human intervention should be carried out after 15 years of enclosure.


Assuntos
Artemisia , Artemisia/fisiologia , China , Clima Desértico , Ecossistema , Pradaria , Humanos , Solo/química , Análise Espacial
5.
Drugs R D ; 22(2): 175-182, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35635717

RESUMO

BACKGROUND AND INTRODUCTION: SHR6390 is a new developed highly effective and selective small-molecule oral CDK4/6 inhibitor. We aimed to evaluate the effect of food on the pharmacokinetics of SHR6390 tablets. METHODS: In an open-label two-way crossover study, 24 healthy Chinese volunteers were randomly divided into Group A and Group B, and 12 volunteers in each group received a single oral dose of a SHR6390 150-mg tablet under fasting and high-fat conditions. Blood samples were collected and determined for pharmacokinetic analyses. A liquid chromatography-tandem mass spectrometry method was developed and validated for determining the SHR6390 concentration. RESULTS: The time to maximum plasma concentration was not significantly affected by a high-fat diet. Compared with the fasting group, maximum plasma concentration, i.e., the area under the concentration-time curve (AUC0-t and AUC0-∞) was altered significantly, as evidenced by an increase of 56.9%, 38.6%, and 37.5% respectively. We identified seven metabolites of SHR6390 from the plasma samples, and we found no sex differences in metabolic pathways. All treatment-emergent adverse events were Grade 1 or 2. CONCLUSIONS: Food intake increased the maximum plasma concentration, AUC0-t, and AUC0-∞ significantly compared with the fasting condition. Meanwhile, single-dose SHR6390 for two treatment cycles is safe. SHR6390 was administered in a fasting status in the pivotal phase III study (NCT03927456) and chosen for the final drug label.


Assuntos
Interações Alimento-Droga , Inibidores de Proteínas Quinases , Administração Oral , Área Sob a Curva , Estudos Cross-Over , Quinase 4 Dependente de Ciclina , Jejum , Voluntários Saudáveis , Humanos , Comprimidos , Equivalência Terapêutica
6.
BMC Med Imaging ; 22(1): 95, 2022 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-35597900

RESUMO

OBJECTIVE: To investigate the value of monochromatic dual-energy CT (DECT) images based on radiomics in differentiating benign from malignant solitary pulmonary nodules. MATERIALS AND METHODS: This retrospective study was approved by the institutional review board, and informed consent was waived. Pathologically confirmed lung nodules smaller than 3 cm with integrated arterial phase and venous phase (AP and VP) gemstone spectral imaging were retrospectively identified. After extracting the radiomic features of each case, principal component analysis (PCA) was used for feature selection, and after training with the logistic regression method, three classification models (ModelAP, ModelVP and ModelCombination) were constructed. The performance was assessed by the area under the receiver operating curve (AUC), and the efficacy of the models was validated using an independent cohort. RESULTS: A total of 153 patients were included and divided into a training cohort (n = 107) and a validation cohort (n = 46). A total of 1130 radiomic features were extracted from each case. The PCA method selected 22, 25 and 35 principal components to construct the three models. The diagnostic accuracy of ModelAP, ModelVP and ModelCombination was 0.8043, 0.6739, and 0.7826 in the validation set, with AUCs of 0.8148 (95% CI 0.682-0.948), 0.7485 (95% CI 0.602-0.895), and 0.8772 (95% CI 0.780-0.974), respectively. The DeLong test showed that there were significant differences in the AUCs between ModelAP and ModelCombination (P = 0.0396) and between ModelVP and ModelCombination (P = 0.0465). However, the difference in AUCs between ModelAP and ModelVP was not significant (P = 0.5061). These results demonstrate that ModelCombination shows a better performance than the other models. Decision curve analysis proved the clinical utility of this model. CONCLUSIONS: We developed a radiomics model based on monochromatic DECT images to identify solitary pulmonary nodules. This model could serve as an effective tool for discriminating benign from malignant pulmonary nodules in patients. The combination of arterial phase and venous phase imaging could significantly improve the model performance.


Assuntos
Neoplasias Pulmonares , Nódulos Pulmonares Múltiplos , Nódulo Pulmonar Solitário , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Nódulos Pulmonares Múltiplos/diagnóstico por imagem , Estudos Retrospectivos , Nódulo Pulmonar Solitário/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos
7.
Drugs R D ; 22(1): 15-23, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34850368

RESUMO

OBJECTIVE: Our objective was to evaluate the pharmacokinetics and bioequivalence of test and reference (JANUMET®) formulations of sitagliptin phosphate/metformin hydrochloride tablets at a single dose of 50 mg/850 mg. METHODS: The study was a randomized, open-label, two-period, double-crossover trial. Volunteers under fasting (n = 24) and fed (n = 24) conditions were given a single oral dose of test or reference formulations of sitagliptin phosphate/metformin hydrochloride tablets 50 mg/850 mg. We used the liquid chromatography tandem mass spectrometry method to determine the concentrations of sitagliptin and metformin in the plasma of subjects. Pharmacokinetic metrics were calculated using the WinNonlin 7.0 program, and bioequivalence was evaluated using SAS 9.4. RESULTS: Under the fasting condition, the 90% confidence intervals (CIs) of geometric mean ratio for maximum plasma drug concentration (Cmax), area under the plasma concentration-time curve from time zero to time t (AUC0-t), and AUC from time zero to infinity (AUC0-∞) of sitagliptin between the test and reference groups were 101.70-120.62%, 99.81-105.61%, and 100.27-106.12%, respectively; for metformin, they were 90.39-111.48%, 94.76-109.12%, and 95.76-110.38%, respectively. Under the fed condition, they were 102.12-117.31%, 100.80-107.81%, and 100.82-107.78%, respectively, for sitagliptin and 95.53-105.22%, 92.76-103.07%, and 93.40-104.14%, respectively, for metformin. Both were generally well-tolerated. CONCLUSION: The two formulations of sitagliptin phosphate/metformin hydrochloride tablets were bioequivalent under fasting and fed conditions in healthy Chinese subjects.


Assuntos
Metformina , Fosfato de Sitagliptina , Área Sob a Curva , China , Estudos Cross-Over , Jejum , Voluntários Saudáveis , Humanos , Comprimidos , Equivalência Terapêutica
8.
Exp Biol Med (Maywood) ; 246(15): 1760-1775, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34024142

RESUMO

Heart regeneration is negligible in humans and mammals but remarkable in some ectotherms. Humans and mammals lack nucleated red blood cells (NRBCs), while ectotherms have sufficient NRBCs. This study used Bufo gargarizan gargarizan, a Chinese toad subspecies, as a model animal to verify our hypothesis that NRBCs participate in myocardial regeneration. NRBC infiltration into myocardium was seen in the healthy toad hearts. Heart needle-injury was used as an enlarged model of physiological cardiomyocyte loss. It recovered quickly and scarlessly. NRBC infiltration increased during the recovery. Transwell assay was done to in vitro explore effects of myocardial injury on NRBCs. In the transwell system, NRBCs could infiltrate into cardiac pieces and could transdifferentiate toward cardiomyocytes. Heart apex cautery caused approximately 5% of the ventricle to be injured to varying degrees. In the mildly to moderately injured regions, NRBC infiltration increased and myocardial regeneration started soon after the inflammatory response; the severely damaged region underwent inflammation, scarring, and vascularity before NRBC infiltration and myocardial regeneration, and recovered scarlessly in four months. NRBCs were seen in the newly formed myocardium. Enzyme-linked immunosorbent assay and Western blotting showed that the levels of tumor necrosis factor-α, interleukin- 1ß, 6, and11, cardiotrophin-1, vascular endothelial growth factor, erythropoietin, matrix metalloproteinase- 2 and 9 in the serum and/or cardiac tissues fluctuated in different patterns during the cardiac injury-regeneration. Cardiotrophin-1 could induce toad NRBC transdifferentiation toward cardiomyocytes in vitro. Taken together, the results suggest that the NRBC is a cell source for cardiomyocyte renewal/regeneration in the toad; cardiomyocyte loss triggers a series of biological processes, facilitating NRBC infiltration and transition to cardiomyocytes. This finding may guide a new direction for improving human myocardial regeneration.


Assuntos
Eritroblastos/metabolismo , Eritrócitos/citologia , Miócitos Cardíacos/citologia , Regeneração/fisiologia , Animais , Bufonidae , Eritroblastos/patologia , Contagem de Eritrócitos/métodos , Modelos Animais , Fatores de Risco , Fator A de Crescimento do Endotélio Vascular/metabolismo
9.
Inorg Chem ; 60(6): 3773-3780, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33615779

RESUMO

Although many strategies have been used to help design effective near-infrared (NIR) luminescent materials, it is still a huge challenge to realize long-wavelength NIR luminescence of diimineplatinum(II) complexes in the solid state. Herein, we have successfully achieved long-wavelength NIR luminescence of a family of diimineplatinum(II) complexes based on a new strategy that combines a one-dimensional (1D) "Pt wire" structure with the electronic effect of the substituent. The structures of six solvated diimineplatinum(II) complexes based on 4,4-dichloro-2,2'-bipyridine or 4,4-dibromo-2,2'-bipyridine and 4-substituted phenylacetylene ligands have been determined, namely, 1·1/2toluene, 2·1/2THF, 3·1/8toluene, 4·1/2THF, 5·1/8CH2Cl2, and 6·1/4toluene. All of them crystallize in the monoclinic space group C2/c or C2/m and stack in the 1D "Pt wire" structure. In the solid state, six complexes exhibited unusual long-wavelength metal-metal-to-ligand charge-transfer luminescence that peaked at 984, 1044, 972, 990, 1022, and 935 nm, respectively. Interestingly, 2·1/2THF has the shortest Pt···Pt distance and the longest emission wavelength among the six complexes. As far as we know, the luminescence of 2·1/2THF at 1044 nm is the longest emission wavelength among known diimineplatinum(II) complexes. Systematic studies revealed that good molecular planarity, suitable substituent position, weak hydrogen-bond-forming ability of the substituents, appropriate molecular bending, and weakening of the interaction between solvated molecules and platinum molecules are conducive to the construction of a 1D "Pt wire" structure of the diimineplatinum(II) complex. Furthermore, the emission energy of the complex is mainly determined by the strength of the Pt-Pt interaction and electronic effect of the substituent.

10.
Exp Ther Med ; 19(4): 2690-2696, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32256750

RESUMO

Icariin, a flavonoid isolated from traditional oriental herbal medicines, has been demonstrated to exhibit several health benefits in animal models and in humans. The aim of the present study was to investigate the effect of Icariin on hyperglycemia in type 2 diabetes mellitus (T2DM) in rats. A model of diabetes was established in 50 Sprague Dawley rats using a high-sugar and high-fat diet and peritoneal injection of streptozotocin. Diabetic rats were divided into five groups: Diabetic control; metformin; and rats treated with three different doses of Icariin, 5, 10 and 20 mg/kg. Body weight and blood glucose levels were measured, and serum adiponectin levels, expression of phospho-AMP mediated protein kinase (p-AMPK) and glucose transporter isoform 4 (GLUT-4) were measured using ELISA, Realtime PCR and western blotting, respectively. Diabetic rats without drug treatment exhibited reduced body weight, increased blood glucose levels and decreased the number of islets. In T2DM rats treated with 10 or 20 mg/kg Icariin, the blood glucose levels were reduced, whereas serum adiponectin levels were not affected. Additionally, the mRNA and protein expression levels of p-AMPK and GLUT-4 protein were increased in the T2DM rats treated with Icariin. In conclusion, in the diabetes rat model, Icariin alleviated the severity of diabetes, and the effects may be associated with reduction of hyperglycemia by activating an AMPK/GLUT-4 pathway.

11.
ACS Appl Mater Interfaces ; 12(10): 12043-12053, 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32069396

RESUMO

Multiemissive sensors are being actively pursued, because of their ratiometric luminescent detection capabilities, which demonstrates better sensitivity and selectivity than conventional single-emission sensors. Herein, we present a trichromatic white-light-emitting metal-organic framework (MOF) composite (Z3) by simultaneously incorporating red/green-emitting Pt/Ru complex cations into porous blue-emitting bio-MOF-1 through post-synthetic modification. With the help of a three-dimensional (3-D) dual-ratiometric luminescence recognition method, and unique turn-on responses of the red emission toward amine compounds (ACs), including NH3 and aliphatic amines, via confinement-induced luminescence enhancement effect, Z3 can work as a dual-ratiometric luminescent sensor for discrimination of 7 out of 11 AC vapors. This work not only provides a new AC sensing mechanism (confinement effect) that can induce a "turn-on" response but also proves that the accuracy and selectivity of composite sensor can be greatly improved through the combination of 3-D recognition method and the confinement effect. Thus, it open up fresh opportunities to develop composite sensors with excellent sensing and differentiating ability.

12.
Braz. J. Pharm. Sci. (Online) ; 56: e18430, 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1132056

RESUMO

To assess the effect of nesiritide on the endothelial function of iliac arteries following endothelia trauma. Right iliac artery trauma was created with a balloon catheter. Ten rabbits were treated with a 4-week subcutaneous injection of nesiritide at a fixed daily dose of 0.1mg/kg. Ten rabbits received daily normal saline injection. Plasma endothelin 1 (ET-1), nitric oxide (NO), and Von Willebrand Factor (vWF) were measured before and after the therapies. Tissue proliferating cell nuclear antigen (PCNA) was measured after the treatment. After the treatment, in the therapeutic group, the area under internal elastic membrane and the residual lumen area were higher than in the normal saline group (P <0.05). The plasma levels of ET-1 (91.6±6.8 vs 114.9±6.3 ng/L, P =0.001), vWF (134.6±10.8% vs 188.8±10.4%, P =0.001) and the ratio of PCNA positive expression (11.7±4.2% vs 36.2±11.4%, P =0.005) in the therapeutic group was lower than in the normal saline group, while the plasma levels of NO was higher (89.7±9.3 vs 43.5±5.3 µmol/L, P =0.001). Nesiritide inhibited remodeling of rabbit iliac artery following endothelial trauma. The inhibition of vascular remodeling may be related to the alleviated endothelial dysfunction and reduced expression of tissue proliferating cell nuclear antigen


Assuntos
Animais , Masculino , Coelhos , Aneurisma Ilíaco/classificação , Endotelina-1/efeitos adversos , Peptídeo Natriurético Encefálico/análise , Células Endoteliais/efeitos dos fármacos , Ferimentos e Lesões/classificação , Fator de von Willebrand/análise , Cateteres/classificação , Artéria Ilíaca , Óxido Nítrico/análise
13.
Chemistry ; 24(38): 9555-9564, 2018 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-29756362

RESUMO

Present here is a new dual ratiometric luminescent probe D which is a trichromatic and white-light-emitting metal-organic framework (MOF) composite facilely obtained by incorporating red/green-emitting complex modules into a blue-emitting MOF. Probe D exhibits remarkable capabilities of sensing different volatile organic solvents (VOSs) via 2D code recognition of the two VOS-dependent MOF ligand-to-module ratios of the emission-peak intensities. For specific VOSs, the resultant luminescent color changes from the starting white color are sharp enough to be visible to the naked eye. Remarkably, D can differentiate solution-phase nitroaromatics and metal ions by recording the evolution of the two ratios during titration processes, enabling an unusual 3D code recognition using the titrant amount as the third dimension for the first time. D also can be used to detect dinoseb, Fe3+ and Al3+ ions quantitatively by analysis of the ratios with detection limits as low as 0.050, 0.41, and 0.12 ppm, respectively. Clearly, such a self-referencing trichromatic probe can maximize the output information and significantly enhance the detection selectivity and sensitivity via multi-dimensional sensing, and has great potentials for practical applications.

14.
Chem Sci ; 9(11): 2918-2926, 2018 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-29732075

RESUMO

Low-cost, high-performance luminescent probes with wide application potential have been actively pursued. Conventional luminescent probes, which rely on single or dual emissions responsive to analyte molecules, demonstrate limited sensitivity and selectivity because the single emissions can be easily affected by many non-analyte factors, while the dual emissions can only offer single-ratiometric luminescent sensing. Here we report a white-light-emitting trichromatic MOF composite (W2) as the first multidimensional ratiometric luminescent probe. It is facilely synthesized by simultaneously incorporating red- and green-emitting iridium and ruthenium complex cations as encapsulated luminescent modules (ELMs) into a porous blue-emitting MOF via ion exchange. Specific volatile organic solvents (VOSs) can cause VOS-dependent changes to the MOF-to-ELM energy transfer efficiencies in W2, while nitroaromatic (NAC) vapors intriguingly and unprecedentedly quench the three emissions at different rates, both of which enable visible luminescent sensing. Each VOS can be correlated to a unique combination of the two MOF-to-ELM ratios of emission-peak heights, enabling a two-dimensional (2D) code recognition. Furthermore, the time-dependent evolution of the two ratios upon exposure to selective NAC vapors can be mapped out, achieving the first 3D code recognition. Both the synthetic and sensing strategies can be further implemented to develop low-cost and effective luminescent probes.

15.
Ying Yong Sheng Tai Xue Bao ; 28(10): 3127-3134, 2017 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-29692129

RESUMO

The estimation of vegetation carbon storage and density of forests at tree layer in Tibet Autonomous Region was calculated based on the eighth forest inventory data using the biomass inventory method, as well as other attributes like tree trunk density and carbon content of different species. The results showed that the total carbon storage at tree layer in Tibet forest ecosystem was 1.067×109 t and the average carbon density was 72.49 t·hm-2. The carbon storage at tree layer of different stands was in the order of arbor forest > scattered wood > sparse forest > alluvial tree. The carbon storage of different forest types at tree layer were in the order of shelterbelt > special purpose forest > timber forest > firewood forest. The proportion of the first mentioned two was 88.5%, and the average carbon density of different forest types at tree layer was 88.09 t·hm-2. The carbon sto-rage and its distribution area at tree layer in different forest groups were in the same order, followed by mature forest > over mature forest > near mature forest > middle aged forest > young forest. The carbon storage in mature forests accounted for 50% of the total carbon storage at tree layer in diffe-rent forest groups. The carbon storage at tree layer in different forest groups increased first and then decreased with the increase of stand ages.


Assuntos
Sequestro de Carbono , Árvores , Biomassa , Carbono , China , Florestas , Tibet
16.
Exp Clin Cardiol ; 18(2): e99-e101, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23940456

RESUMO

OBJECTIVE: To investigate the effect of ischemic postconditioning on the expression of matrix metalloproteinase (MMP)-2 during ischemia-reperfusion of myocardium in a rabbit model. METHODS: Thirty-six male New Zealand white rabbits were randomly divided into sham, ischemia-reperfusion and ischemic postconditioning groups. Myocardial ischemia-reperfusion was created by ligating the left anterior descending coronary artery for 30 min followed by 3 h of reperfusion. Myocardial infarction sizes were determined by dual staining with triphenyltetrazolium chloride and trypan blue. Plasma levels of MMP-2 were measured using ELISA. Myocardial MMP-2 messenger RNA was analyzed by reverse transcription polymerase chain reaction. RESULTS: The mean (± SD) infarct size in the ischemic postconditioning group was significantly smaller compared with the ischemia-reperfusion group (37.1±3.8% versus 57.5±1.9%; P=0.02). The incidence of ventricular tachycardia in the ischemic postconditioning group was also lower than in the ischemia-reperfusion group (8.5% versus 75%; P=0.003). MMP-2 messenger RNA expression in the ischemic postconditioning group was significantly lower compared with the ischemia-reperfusion group (0.4944±0.0476 versus 0.6989±0.0694; P=0.02). CONCLUSION: Ischemic postconditioning reduces myocardial ischemia-reperfusion injury, possibly by inhibiting the expression of MMP-2.

17.
Dalton Trans ; 42(16): 5711-7, 2013 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-23443651

RESUMO

The preparation, structures and properties of 3d-4f compounds, undecanuclear [La2Ni9(Gly)12(IDA)3(µ3-OH)3][La(H2O)9][Na3(H2O)7(ClO4)3](ClO4)6·5H2O (1) and isostructural heptadecanuclear [Ln5Ni12(Gly)12(IDA)6(µ3-OH)9(H2O)3](ClO4)6·11H2O (Ln = Gd (2); Nd (3); Sm (4); Tb (5); Dy (6); Y (7)) based on mixed glycine (HGly) and iminodiacetate acid (H2IDA) ligands were described. The structure of the [La2Ni9(µ3-OH)3(IDA)3(Gly)12](3+) cationic cluster in 1 can be described as a face-shared and La-centered dioctahedron. However, the [Ln5Ni12(Gly)12(IDA)6(µ3-OH)9(H2O)3](6+) cationic clusters in 2-7 bear an onion-like {Ln5}⊂{Ni12} structure, where the trigonal bipyramid {Ln5} core is encapsulated by the outer triangular orthobicupola {Ni12} shell. Magnetic studies have been performed for these compounds, and 2 displays dominant ferromagnetic coupling and has a large magnetocaloric effect (21.8 J kg(-1) K(-1), ΔH = 7 T).

18.
Dalton Trans ; 41(43): 13264-6, 2012 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-23044929

RESUMO

With formate as ligand, two 1-D 3d-4f compounds (linear and zigzag) based on pyramidal {TbCu(4)} unit were obtained. Chair-like [(H(2)O)(2)(ClO(4))(2)](2-) clusters and µ(5)-η(1):η(4) bridging mode of formate were observed in the linear one which also displays slow relaxation of the magnetization.

19.
Heart Lung Circ ; 21(9): 551-5, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22608834

RESUMO

BACKGROUND: This study was designed to investigate the effect of nesiritide, a recombinant B-type natriuretic peptide (BNP), on plasma aldosterone and vascular remodelling following balloon-induced endothelial injuries to the iliac arteries. METHODS: Twenty-four male New Zealand rabbits were divided into nesiritide (0.1mg/kg/day, sc, for 4 weeks, n=12) and saline-treated control group (n=12). A balloon catheter was inserted to the right iliac artery to induce endothelia injuries. Plasma aldosterone was measured before and 28 days after the treatment by radioimmunoassay. RESULTS: The area under internal elastic membrane (657.1±129.6 vs 486.7±124.0µm(2), P=0.02) and the area under external elastic membrane (1506.2±188.3.9 vs 1185.0±202.9µm(2), P=0.02) in the nesiritide group were greater than in the control group. The stenosis ratio in the nesiritide group was lower than in the control group (20.1±6.2% vs 39.6±9.5%, P=0.01). The plasma levels of aldosterone (2.03±0.31 vs 3.00±0.29ng/L, P<0.01) in the nesiritide group was lower than in the control group. Pearson's correlation analysis showed a positive correlation between the levels of plasma aldosterone and the stenosis ratio of the injured right iliac arteries (r=0.622, P=0.002). CONCLUSION: Nesiritide treatment reduced stenosis ratio of the rabbit iliac artery following balloon-induced endothelial injuries, and the reduced stenosis ratio was associated with a reduction in the plasma aldosterone concentrations.


Assuntos
Aldosterona/metabolismo , Artéria Ilíaca/lesões , Artéria Ilíaca/fisiopatologia , Peptídeo Natriurético Encefálico/farmacologia , Animais , Constrição Patológica/sangue , Constrição Patológica/tratamento farmacológico , Constrição Patológica/fisiopatologia , Artéria Ilíaca/metabolismo , Masculino , Coelhos , Proteínas Recombinantes/farmacologia
20.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 41(2): 166-70, 2012 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-22499513

RESUMO

OBJECTIVE: To compare the effects of mannitol and hypertonic saline (HS) in treatment of intracranial hypertension (ICH) of rabbits. METHODS: The animal mode of ICH was established by perfusing artificial cerebrospinal fluids (aCSF) with controlled pressure into the cerebral ventricles of rabbits. The mean arterial pressure, respiratory rate, tidal volume, perfusion rate of aCSF and water content of cerebrum were investigated in rabbits with ICH after a single bolus of 20% mannitol (5 ml/kg), 7.5% HS (2.2 ml/kg) or 23.4% HS (2.2 ml/kg). RESULTS: After the intracranial pressure was elevated from 15 cmH2O to 75 cmH2O, the mean arterial pressure was increased and the tidal volume was decreased. After treatment by 20% mannitol, 7.5% HS or 23.4% HS, the increased percentage of mean arterial pressure and the decreased percentage of tidal volume were similar to the changes in control group. However, the perfusion rate of CSF was increased and water content of cerebrum was decreased after treatment by either 20% mannitol or 23.4% HS, but not by 7.5% HS. No different effects were found between 20% mannitol and 23.4% HS. CONCLUSION: With the similar osmotic burden, 20% mannitol is more effective in treating ICH than 7.5% HS. With higher osmotic load, the efficacy of HS is enhanced, and 23.4% HS may be used as an alternative to mannitol in treatment of ICH.


Assuntos
Hipertensão Intracraniana/tratamento farmacológico , Manitol/uso terapêutico , Solução Salina Hipertônica/uso terapêutico , Animais , Modelos Animais de Doenças , Feminino , Masculino , Manitol/administração & dosagem , Coelhos , Solução Salina Hipertônica/administração & dosagem
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