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1.
Artigo em Inglês | MEDLINE | ID: mdl-38401066

RESUMO

Objective: Craniopharyngioma (CP) is an intracranial congenital epithelial tumor that can occur at any age. CP tumors are histologically benign (WHO grade I), and childhood­onset CP (CO-CP) patients have a high rate of survival. The major concern for CO-CP patients is delayed diagnosis. Delayed diagnosis can further lead to serious adverse consequences such as acute and chronic complications, thereby endangering the life of the patient.We evaluated the early-stage clinical characteristics of CO-CP patients to provide clues for making rapid and accurate diagnoses. Methods: This was a retrospective, single-center study. We retrospectively reviewed all pediatric patients (<18 years of age) undergoing CP surgery between 2012 and 2019 at a single institution. Data including demographic data, clinical presentation, neuroendocrine dysfunction, and tumor imaging characteristics at diagnosis were analyzed. Results: The average age of the 192 children in this study was 7.32±3.94 (0-16) years, 91.0% were diagnosed when under 14 years old, and 92.7% of patients had at least one clinical symptom, and 90.7% of tumors have a diameter greater than 2cm, and 95.9% of tumor consistency was mixed or cystic, and 89.0% of tumors found calcification. The patients with hydrocephalus had higher BMI values than those without hydrocephalus (P = .006), and the incidence of calcification of tumors significantly decreased with age (P = .027). Conclusions: For pediatric patients with calcification, >2 cm, cystic or mixed intracranial mass lesions, CP tumors should be considered, and early neuroendocrine function evaluation and further surgical treatment should be performed to avoid delayed diagnosis.

2.
Sci Total Environ ; 914: 170061, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38218468

RESUMO

Rapid climate warming is altering multiple ecosystem functions of alpine grasslands. However, the responses of the above- and belowground ecosystem multifunctionality (EMF) to climate warming might exhibit difference in semi-arid alpine grasslands. Based on manipulative field experiments at an alpine meadow and an alpine steppe, we explored warming effects on the functioning of alpine grassland ecosystems on the Tibetan Plateau. Warming significantly decreased plant diversity and aboveground biomass, but tended to increase belowground biomass, soil carbon, and soil nutrient contents. Experimental warming generally had neutral effects on the EMF of both alpine grasslands. Nevertheless, warming differentially affects the above- and belowground ecosystem functioning of Tibetan semi-arid alpine grasslands, with the aboveground EMF (AEMF) deceased but the belowground EMF (BEMF) increased under warmer conditions. Our results further showed that the negative effect of experimental warming on AEMF was mainly regulated by the changes of plant and soil biodiversity. However, plant productivity had a pivotal role in propelling the positive effect of warming on BEMF. Our results emphasized the potential impacts of plant and soil biodiversity, productivity, and soil nutrients in maintaining the EMF of alpine grasslands, which could offer novel views for sustainable management of Tibetan semi-arid alpine ecosystems.


Assuntos
Ecossistema , Pradaria , Mudança Climática , Biomassa , Plantas , Solo , Tibet
3.
Nat Protoc ; 19(2): 539-564, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38049624

RESUMO

Two-dimensional (2D) protein films can be used to modify the properties of surfaces, and find applications predominantly in the fields of biomaterials, lithography, optics and electronics. However, it is difficult to produce scalable homogeneous and robust protein films with an easy, low-cost, green and efficient method. Further challenges include encapsulating and releasing functional building blocks in the film without inactivating them, and maintaining or improving the bioactivities of proteins used for the formation of the films. Here we detail the process to prepare large 2D protein films with user-defined features and structures via the amyloid-like aggregation of commonly synthesized proteins. These films can be synthesized at meter scales, have high interface adhesion, high functional expansibility and tunable functional properties, obtained by controlling the position of the disulfide bond breakage. For example, we can retain or even enhance the natural antibacterial, biomineralization and antifouling activity of proteins involved in film formation, and the properties can also be expanded through the physical blending or chemical grafting of additional functional blocks on the surface of the film. A 2D protein film can be prepared in ~3 h using four alternative coating techniques: immersion, transfer, hydrogel stamping and spraying. The characterization process of the film requires ~5 d. The procedure can be carried out by users with basic expertise in materials science.


Assuntos
Materiais Biocompatíveis , Proteínas , Antibacterianos
4.
Polymers (Basel) ; 15(19)2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37836017

RESUMO

Carbon nanotubes (CNTs) and styrene-butadiene-styrene (SBS) are used as reinforcing modifiers in asphalt sealants due to their excellent properties, which can effectively improve the internal structure of the sealant and enhance its mechanical properties. Based on this background, two SBS/CNT-modified asphalt sealants were identified and selected by the orthogonal experimental method and compared with two commercially available sealants. The softening point, flow value, multi-temperature frequency scan test, and multiple stress creep recovery test were used to study the high-temperature rheological properties and aging resistance of four types of sealants. The overall evaluation shows that the proportion of the sealant compound's preparation material is 1% by weight of CNT doping, 5% by weight of SBS doping, and 5% by weight of furfural-extracted-oil doping. The results show that the addition of SBS and CNTs more significantly improves the fatigue resistance of the sealants. With the CAM model, C1.0S5F5 reflects a better relaxation property, which better avoids secondary cracking after the construction of the sealant. With the Burgers model, C1.0S5F5 shows excellent deformation resistance under heavy traffic conditions. In summary, conventional performance indicators, such as the softening point and flow value of SBS/CNT-modified asphalt sealants, can meet the specification requirements and show good high-temperature stability and anti-aging properties compared to commercially available sealants.

5.
Nat Commun ; 14(1): 5145, 2023 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-37620335

RESUMO

Underwater adhesive proteins secreted by organisms greatly inspires the development of underwater glue. However, except for specific proteins such as mussel adhesive protein, barnacle cement proteins, curli protein and their related recombinant proteins, it is believed that abundant common proteins cannot be converted into underwater glue. Here, we demonstrate that unfolded common proteins exhibit high affinity to surfaces and strong internal cohesion via amyloid-like aggregation in water. Using bovine serum albumin (BSA) as a model protein, we obtain a stable unfolded protein by cleaving the disulfide bonds and maintaining the unfolded state by means of stabilizing agents such as trifluoroethanol (TFE) and urea. The diffusion of stabilizing agents into water exposes the hydrophobic residues of an unfolded protein and initiates aggregation of the unfolded protein into a solid block. A robust and stable underwater glue can thus be prepared from tens of common proteins. This strategy deciphers a general code in common proteins to construct robust underwater glue from abundant biomass.


Assuntos
Excipientes , Soroalbumina Bovina , Transporte Biológico , Proteínas Amiloidogênicas , Água
6.
Mater Today Bio ; 16: 100407, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36090610

RESUMO

Surface engineering of particles based on a polymeric coating is of great interest in materials design and applications. Due to the disadvantages of non-biodegradability and undesirable biocompatibility, the application of petroleum-based synthetic polymers coating in the biomedical field has been greatly limited. In addition, there is lack of a universal surface modification method to functionalize particles of different compositions, sizes, shapes, and structures. Thus, it is imperative to develop a versatile biopolymeric coating with good biocompatibility and tunable biodegradability for the preparation of functional particle materials regardless of their surface chemical and physical structures. Recently, the natural polysaccharide polymers (e.g. chitosan and cellulose), polyphenol-based biopolymers (e.g. polydopamine and tannic acid), and proteins (e.g. amyloid-like aggregates) have been utilized in surface modification of particles, and applications of these modified particles in the field of biomedicine have been also intensively exploited. In this review, the preparation of the above three coatings on particles surface are summarized, and the applications of these materials in drug loading/release, biomineralization, cell immobilization/protection, enzyme immobilization/protection, and antibacterial/antiviral are exemplified. Finally, the challenges and the future research directions on biopolymer coating for particles surface engineering are prospected.

7.
Cell Mol Biol (Noisy-le-grand) ; 68(3): 67-76, 2022 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-35988190

RESUMO

In cardiovascular diseases, myocardial infarction is the most important cause of chronic heart failure. According to reports, more than 70% of patients with chronic heart failure suffer from myocardial infarction. Nano sodium alginate-bioglass has attracted more and more attention in the treatment of myocardial infarction due to its good cell proliferation. In order to understand the effect of nano-sodium alginate-bioglass on myocardial infarction, we added nano-sodium alginate-bioglass in the treatment process. The calcium ions released by the bio-glass during the slurry preparation process partially cross-link the sodium alginate, which helps to restore the heart function of myocardial infarction. Add nano-seaweed Sodium-bioglass can significantly promote the proliferation of heart cells. Through the test of different groups and the results of cell experiments, we have obtained the best recovery effect of myocardial infarction when the bioglass content is about 30%, and the changes in the vitality of heart cells can be seen most clearly.


Assuntos
Insuficiência Cardíaca , Infarto do Miocárdio , Alginatos/farmacologia , Cerâmica , Humanos , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/tratamento farmacológico
8.
Am J Transl Res ; 14(6): 4114-4123, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35836903

RESUMO

OBJECTIVE: To investigate the clinical efficacy and safety of comprehensive nursing intervention in acute leukemia patients with myelosuppression after chemotherapy. METHODS: Eighty acute leukemia patients with myelosuppression after chemotherapy admitted to our hospital from April 2018 to December 2021 were selected and divided, according to the nursing mode, as the conventional group (n=40) with routine nursing mode and the comprehensive group (n=40) with the comprehensive nursing mode. Patients' anxiety (Self-Rating Anxiety Scale, SAS) scores, depression (Self-Rating Depression Scale, SDS) scores, occurrence of complications, nursing satisfaction, nursing experience, complaint rate, and Visual Analogue Scale (VAS) score were compared between the two groups so as to analyze the efficacy and safety of comprehensive nursing intervention. The improvement of quality of life in the two groups was observed and analyzed using the short form of quality of life measurement (WHOQOL-BREF). Logistic regression analysis was performed to analyze the risk factors for nosocomial infection in patients with comprehensive nursing intervention. RESULTS: No statistically significant differences in SAS and SDS scores between the two groups were found prior nursing (P>0.05), while after nursing, scores in the two groups both decreased, with those in the comprehensive group significantly lower than in the conventional group (P<0.05). The incidence of complications after nursing in the comprehensive group was significantly lower than that in the conventional group, and the difference was statistically significant (P<0.05). Nursing satisfaction of patients in the comprehensive group were significantly higher than that in the conventional group (P<0.05). After nursing, the nursing experience of the comprehensive group was significantly better than that of the conventional group (P<0.05); the complaint rate of the comprehensive group was significantly lower than that of the conventional group (P<0.05); before nursing, there was no significant difference in the VAS scores between the two groups of patients (P>0.05); after nursing, the VAS score of the comprehensive group was significantly lower than that of the conventional group (P<0.05). Before nursing, there was no significant difference in WHOQOL-BREF scores between the two groups (P>0.05); after nursing, the comprehensive group was higher than the conventional group. Among the 40 patients in the comprehensive nursing group, 15 patients developed infection. The number of neutrophils, age above 40, white blood cell count, hemoglobin content, high-intensity chemotherapy and glucocorticoid therapy were independent risk factors for nosocomial infection in patients with comprehensive nursing intervention (P<0.05). CONCLUSION: Comprehensive nursing intervention for patients with myelosuppression after chemotherapy for acute leukemia can effectively improve the patient's nursing experience, reduce the patient's complaint rate, alleviate the patient's physical pain, relieve the patient's anxiety, depression and other negative emotions, and reduce the patient's complications, suggesting that comprehensive nursing intervention exerts better clinical efficacy and has high safety, which merits promotion clinically.

9.
Front Plant Sci ; 12: 824296, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35222457

RESUMO

Precipitation and temperature are major controls on multiple ecosystem functions in alpine grasslands. There is scant evidence for the interactive effects of temperature and precipitation changes on the ecosystem multifunctionality (EMF) in alpine meadows. To explore the interactive effects of temperature and precipitation changes on the EMF in alpine meadows, we transplanted meadow blocks reciprocally among three altitudes (4,650, 4,950, and 5,200 m) on the central Tibetan Plateau. Compared with the home sites (control), the EMF has a trend to increase when meadow blocks were downward transplanted (experimental warming) to the high-precipitation sites but decrease as meadow blocks were downward transplanted to the low-precipitation sites. However, the experimental cooling (upward transplantation) consistently reduced the EMF regardless of the precipitation change. The increase of EMF under the experimental warming was closely related to the variation of both plant and soil functions, whereas the reduction of EMF under the cooling was highly correlated with the decrease of plant function. Our results highlight that climate warming effects on the EMF are greatly associated with precipitation changes in the semi-arid alpine ecosystems.

10.
Sensors (Basel) ; 20(18)2020 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-32937998

RESUMO

Recently, many video steganography algorithms based on the intra-prediction mode (IPM) have been adaptive steganography algorithms. These algorithms usually focus on the research about mapping rules and distortion functions while ignoring the fact that adaptive steganography may not be suitable for video steganography based on the intra-prediction mode; this is because the adaptive steganography algorithm must first calculate the loss of all cover before the first secret message is embedded. However, the modification of an IPM may change the pixel values of the current block and adjacent blocks, which will lead to the change of the loss of the following blocks. In order to avoid this problem, a new secure video steganography based on a novel embedding strategy is proposed in this paper. Video steganography is combined with video encoding. Firstly, the frame is encoded by an original encoder and all the relevant information is saved. The candidate block is found according to the relevant information and mapping rules. Then every qualified block is analyzed, and a one-bit message is embedded during intra-prediction encoding. At last, if the IPM of this block is changed, the values of the residual are modified in order to keep the optimality of the modified IPM. Experimental results indicate that our algorithm has good security performance and little impact on video quality.

11.
BMC Cardiovasc Disord ; 20(1): 326, 2020 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-32641068

RESUMO

OBJECTIVE: To investigate the correlation between ischemia-modified albumin (IMA) levels and coronary collateral circulation (CCC) in patients with chronic total occlusive (CTO). METHODS: Coronary angiography was performed in the Department of Cardiology, Zhongnan Hospital of Wuhan University from 2017 to 08 to 2019-02 to identify 128 patients with CTO lesions in at least one major coronary artery. According to the Rentrop evaluation criteria, the degree of CCC formation was divided into the poor CCC formation group (Rentrop0-1 grade,n = 69) and the good CCC formation group (Rentrop2-3 grade,n = 59). The IMA level of the patients was measured using an albumin-cobalt binding assay. The general data, routine blood panel, total bilirubin (TBIL), blood lipids, uric acid (UA), left ventricular ejection fraction (LVEF) and other indicators of the patients were recorded and analyzed while assessing the patients' blood vessel occlusion. RESULTS: The proportion of platelet count and diabetes in the poor CCC group was higher than that in the good CCC group (P < 0.05). The ratio of ischemia-modified albumin and total bilirubin in the poor CCC group was lower than that in the good CCC group (P < 0.05). Multivariate logistic regression analysis showed that ischemia-modified albumin was positively correlated with CCC formation [OR = 1.190,95% CI (1.092-1.297),P < 0.001], while diabetes was negatively correlated with CCC formation [OR = 0.285,95% CI (0.094-0.864), P < 0.05]. Ischemic modified albumin predicted good formation of CCC according to the ROC curve, and the area under the ROC curve was 0.769(95% CI,0.686-0.851, P<0.001); the optimal cut-off value was 63.35 KU/L, and the sensitivity was 71.2%,specificity is 71%. CONCLUSION: The IMA level is closely related to good formation of CCC. Higher IMA levels can be used as an effective predictor of good CCC formation in patients with CTO.


Assuntos
Circulação Colateral , Circulação Coronária , Oclusão Coronária/sangue , Oclusão Coronária/fisiopatologia , Idoso , Biomarcadores/sangue , Doença Crônica , Angiografia Coronária , Oclusão Coronária/diagnóstico por imagem , Oclusão Coronária/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Albumina Sérica Humana
12.
Front Plant Sci ; 11: 607, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32582230

RESUMO

Dual-purpose crops are grazed during their vegetative phase and allowed to regrow to produce grain. Grazing slow-developing winter cereals (wheat, barley, and triticale) is common, but there is also potential to graze faster-developing spring cereals used in regions with shorter-growing seasons. Defoliation in faster-developing genotypes has risks of larger yield penalties, however, little is known about genotypic characteristics that may improve recovery after grazing. Four experiments examined 7 spring wheat and 2 barley cultivars with differing physiological attributes (phenological development rate, putative capacity to accumulate soluble carbohydrates, and tillering capacity) that may influence the capacity of spring wheat to recover after defoliation. Defoliated and undefoliated crops were compared to assess physiological differences between cultivars including recovery of biomass, leaf area and radiation interception at anthesis, and subsequent crop grain yield and yield components. All genotypes had similar responses to defoliation treatments indicating that the physiological attributes studied played little part in mitigating yield penalties after defoliation. Despite some differences in yield components amongst cultivars, defoliation did not adversely affect cultivars with different yield component combinations under non-water limited conditions. Later and intense defoliation (around GS30/31) resulted in large yield penalties (40%) which reduced both grain number and kernel mass. However, earlier defoliation (before GS28) induced small or insignificant yield penalties. Defoliation often reduced canopy radiation interception and crop biomass at anthesis but this rarely translated into large yield penalties. These studies further demonstrate that shorter season spring cereals can provide valuable forage (up to 1.2 t DM/ha) for grazing during early vegetative growth without inducing large yield penalties. This study suggests that beyond appropriate phenology, there were no other specific characteristics of cultivars that improved the recovery after grazing. Hence farmers don't need specific dual-purpose cultivars and can still focus on those that optimize grain yield potential for a particular environment and sowing date. The timing and intensity of defoliation appear to be larger drivers of yield recovery in spring cereals and better understanding of these relationships are needed to provide grazing management guidelines that mitigate risk of yield penalties in dual-purpose cereal crops.

13.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 31(3): 341-345, 2019 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-30914097

RESUMO

OBJECTIVE: To investigate the effects of autophagy on N-methy-D-aspartate (NMDA) receptor and its subunit NR2B and behavioral test in a rat model of neuropathic pain (NP). METHODS: Male Sprague-Dawley (SD) rats were divided into sham group, NP group, autophagy inhibitor 3-methyladenine (3-MA) pretreatment group (3-MA+NP group) and autophagy inducer rapamyein (Rap) group (Rap+NP group) by random number table with 22 rats in each group. NP animal model was reproduced by ligating sciatic nerve, while sciatic nerve of the rats in the sham group were only exposed but not ligated. The rats in two pretreatment groups were intraperitoneally challenged with 3-MA 15 mg/kg or Rap 10 mg/kg injection 1 hour before operation. Mechanical paw withdrawal threshold (MWT) and thermal paw withdrawal latency (TWL) were measured before and 1, 3, 7, 14 days after operation in each group. Spinal cord tissues were harvested at 1 day and 7 days after operation for autophagosome observation by electron microscope. The expressions of autophagy protein microtubule-associated protein 1 light chain 3-II (LC3-II), Beclin1, and NMDA, NR2B were determined by Western Blot. The positive expression of LC3 was detected by immunofluorescence. RESULTS: Compared with sham group, the MWT and TWL of rats in NP group were decreased gradually with the prolongation of operation time, the number of autophagosome, the expressions of LC3-II, Beclin1, NMDA, NR2B, and the positive expression of LC3 in spinal cord were significantly increased at 1 day after operation and till 7 days, which indicated that NP led to hyperpathia and autophagy activation. Compared with NP group, MWT was significantly further decreased, TWL was further shortened, the number of autophagosome was decreased, the expressions of LC3-II and Beclin1 in spinal cord were decreased, and NMDA and NR2B expressions were further increased after 3-MA pretreatment, with significant differences at 1 day after operation [MWT (g): 29.4±2.4 vs. 42.5±6.6, TWL (s): 7.2±1.0 vs. 8.8±1.1, LC3-II/ß-actin: 0.38±0.03 vs. 0.52±0.07, Beclin1/ß-actin: 0.29±0.06 vs. 0.59±0.05, NMDA/ß-actin: 0.62±0.06 vs. 0.50±0.06, NR2B/ß-actin: 0.57±0.03 vs. 0.46±0.03, all P < 0.05]. Immunofluorescence staining confirmed that the positive expression of LC3 was significantly decreased. Rap pretreatment could increase MWT, TWL and the number of autophagosome, increase LC3-II and Beclin1 expressions in spinal cord, and decrease NMDA and NR2B expressions in NP rats, and significant differences at 1 day after operation were found as compared with those in NP group [MWT (g): 49.4±4.4 vs. 42.5±6.6, TWL (s): 10.5±1.2 vs. 8.8±1.1, LC3-II/ß-actin: 0.67±0.09 vs. 0.52±0.07, Beclin1/ß-actin: 0.71±0.08 vs. 0.59±0.05, NMDA/ß-actin: 0.40±0.05 vs. 0.50±0.06, NR2B/ß-actin: 0.34±0.04 vs. 0.46±0.03, all P < 0.05], and immunofluorescence showed that the positive expression of LC3 was increased and lasted for 7 days. It indicated that Rap could increase the activity of autophagy, alleviate the occurrence of hyperalgesia, and reduce the expressions of NMDA receptor and its NR2B subunit. CONCLUSIONS: NP could regulate the variety of NMDA/NR2B and hyperalgesia via increasing autophagy.


Assuntos
Autofagia/fisiologia , Hiperalgesia/metabolismo , Neuralgia/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Animais , Modelos Animais de Doenças , Masculino , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
15.
Vaccine ; 32(46): 6115-21, 2014 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-25236587

RESUMO

Vibrio parahaemolyticus is an important halophilous pathogen that can cause not only a broad range of disease in aquatic animals but also serious seafood-borne illness in humans as a result of the consumption of seafood. To avoid the use of antibiotics, it is critical to identify protective antigens for developing highly effective vaccines against this pathogen. Outer membrane proteins (OMPs) have been suggested as potential vaccine candidates for conferring protection against infection. In this study, we identified novel immunogenic OMPs using an immune assay with serum antibodies from mice infected by V. parahaemolyticus combined with mass spectrometry analysis. Nine OMPs were identified to be immunogenic proteins, and four of these identified proteins with relatively low abundance in OMP profiles, LptD, VP0802, VP1243 and VP0966, were determined to have immunogenicity for the first time. One OMP of interest, VP0802, is highly conserved among major Vibrio species and was proposed to adopt a ß-barrel conformation and to be a member of the OprD protein family by bioinformatic analysis. The immunogenicity and protective efficacy of VP0802 were further evaluated by bacterial challenge postimmunization in a mouse model. VP0802 was confirmed to be highly immunogenic and to offer strong protection against V. parahaemolyticus infection, with an RPS of at least 66.7. Efficient clearance of bacteria from the blood of vaccinated mice was also observed. Moreover, upregulation of VP0802 expression was found after bacteria were exposed to fresh sera. These data, taken together, suggest that VP0802 is a promising candidate for the development of a subunit vaccine to prevent V. parahaemolyticus infection.


Assuntos
Proteínas da Membrana Bacteriana Externa/imunologia , Vacinas Bacterianas/imunologia , Vibrioses/prevenção & controle , Vibrio parahaemolyticus , Animais , Anticorpos Antibacterianos/sangue , Humanos , Camundongos Endogâmicos ICR , Estrutura Terciária de Proteína , Proteômica , Ensaios de Anticorpos Bactericidas Séricos
16.
Eur J Pharmacol ; 740: 9-14, 2014 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-25008071

RESUMO

Atorvastatin (AT) has been alternatively used for managing diabetic complications in clinic. However, AT-related therapeutic potentiality remains relatively unexplored, especially in diabetic nephropathy. This study aimed to investigate the underlying potentiality that AT exerted on anti-diabetic nephropathy role against streptozotocin (STZ)-induced kidney injury in rats. STZ-diabetic rats were intragastrically administered with AT (10, 20 mg/kg/d) for consecutive 8 weeks. The effects of AT on body weight, levels of blood glucose, lipometabolism, redox state, cellular metabolism, regulator factor and kidney morphological changes were monitored by routine measurement, biochemistry assay, PT-PCR analysis, ultrastructural and pathological observations, respectively. Compared with the diabetic nephropathy rats, AT elevated the body weight of diabetic nephropathy rats (P<0.01), effectively reduced the blood glucose level (P<0.01), increased the levels of insulin and high-density lipoprotein cholesterol (HDL-C) in plasma (P<0.01), and decreased the 24 h urine protein content and serum concentrations of low-density lipoprotein cholesterol (LDL-C) (P<0.01). Meanwhile, increase in kidney tissue, the intrarenal activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) were enhanced, while the malonaldehyde (MDA) content was reduced (P<0.01). In addition, the expression of transforming growth factor beta 1 (TGF-ß1) mRNA in kidney tissue was notably down-regulated (P<0.01). Furthermore, AT contributed to alleviating STZ-induced nephritic damages in rats. These results demonstrate that atorvastatin exerts the effective protective role against kidney injuries of STZ-induced diabetic nephropathy rat, which the underlying mechanisms are associated with ameliorating glyco, lipometabolism, enhancing antioxidant ability, and mitigating renal damage.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Nefropatias Diabéticas/tratamento farmacológico , Ácidos Heptanoicos/uso terapêutico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Hipoglicemiantes/uso terapêutico , Proteinúria/tratamento farmacológico , Pirróis/uso terapêutico , Animais , Atorvastatina , Glicemia/análise , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Nefropatias Diabéticas/metabolismo , Nefropatias Diabéticas/patologia , Ácidos Heptanoicos/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Hipoglicemiantes/farmacologia , Insulina/sangue , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Lipoproteínas HDL/sangue , Lipoproteínas LDL/sangue , Masculino , Proteinúria/metabolismo , Proteinúria/patologia , Pirróis/farmacologia , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Estreptozocina , Fator de Crescimento Transformador beta1/genética
17.
Mol Med Rep ; 9(6): 2245-50, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24676597

RESUMO

The aim of the present study was to examine the effect of exogenous IL-10 transfected rat dendritic cells (DCs) in corneal allografts. Rat lymphocyte separation medium and a cytokine induction method was used to extract and culture precursor cells of rat bone marrow-derived dendritic cells. A corneal transplant model was established, with Sprague-Dawley (SD) rats as the recipients and Wistar rats as the donors. Flow cytometry (FCM) was used to detect the expression of CD83, which indicates a mature dendritic cell, and a specific cell surface stimulatory molecule CD86. Western blot analysis was used to detect interleukin (IL)-10 protein expression and RT-PCR was used to detect cytokine IL-10, IL-2 and TGF-ß mRNA expression in each group. Compared with the other groups, the survival time of corneal grafts in the IL-10-green fluorescent protein (GFP)-DC group was significantly prolonged and H&E staining demonstrated mild graft edema and inflammatory cell infiltration. There was a high expression of IL-10 and a low expression of the surface antigens, CD83 and CD86, with a lower proliferation of T lymphocytes in the IL-10-GFP-DC group. The expression of IL-10 and TGF-ß in the IL-10-GFP-DC group was higher than that in the other groups, while the expression of IL-2 was lower. The transfection of the IL-10 gene inhibited dendritic cell maturation. IL-10 gene-modified immature dendritic cells (imDC) were able to inhibit corneal allograft rejection and induce immune tolerance to prolong the survival time of the corneal graft. The Th1/Th2 deviation and the high expression of TGF-ß may lead to immune tolerance.


Assuntos
Córnea/imunologia , Córnea/metabolismo , Transplante de Córnea , Tolerância Imunológica , Interleucina-10/metabolismo , Células Th1/imunologia , Células Th2/imunologia , Animais , Córnea/citologia , Citocinas/genética , Citocinas/metabolismo , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Feminino , Expressão Gênica , Tolerância Imunológica/genética , Imunofenotipagem , Interleucina-10/genética , Ativação Linfocitária/imunologia , Masculino , Fenótipo , Ratos , Células Th1/metabolismo , Células Th2/metabolismo
18.
Chemistry ; 20(4): 1167-75, 2014 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-24338790

RESUMO

The activation of C-H bonds in alkanes is currently a hot research topic in chemistry. The atomic oxygen radical anion (O(-·)) is an important species in C-H activation. The mechanistic details of C-H activation by O(-·) radicals can be well understood by studying the reactions between O(-·) containing transition metal oxide clusters and alkanes. Here the reactivity of scandium oxide cluster anions toward n-butane was studied by using a high-resolution time-of-flight mass spectrometer coupled with a fast flow reactor. Hydrogen atom abstraction (HAA) from n-butane by (Sc2O3)(N)O(-) (N=1-18) clusters was observed. The reactivity of (Sc2O3)(N)O(-) (N=1-18) clusters is significantly sizedependent and the highest reactivity was observed for N=4 (Sc8O13(-)) and 12 (Sc24O37(-)). Larger (Sc2O3)(N)O(-) clusters generally have higher reactivity than the smaller ones. Density functional theory calculations were performed to interpret the reactivity of (Sc2O3)(N)O(-) (N=1-5) clusters, which were found to contain the O(-·) radicals as the active sites. The local charge environment around the O(-·) radicals was demonstrated to control the experimentally observed size-dependent reactivity. This work is among the first to report HAA reactivity of cluster anions with dimensions up to nanosize toward alkane molecules. The anionic O(-·) containing scandium oxide clusters are found to be more reactive than the corresponding cationic ones in the C-H bond activation.

19.
Zhongguo Zhong Yao Za Zhi ; 39(19): 3719-22, 2014 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-25612427

RESUMO

Breviscapine, a flavone glucuronide, is a cardiovascular medicine extracted from a Chinese herb Erigeron breviscapinus. Modern pharmacological research shows breviscapine has a therapeutic effect on cardiovascular diseases such as cerebral thrombus,cerebral ischemia hemiparesis and platelet aggregation et al. However, its poor water solubility and low bioavailability in vivo severely restrict the clinical application. In this article, we reviewed the marketing preparations of breviscapine and its research progress on the new dosage forms.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Medicamentos de Ervas Chinesas/administração & dosagem , Flavonoides/administração & dosagem , Pesquisa Biomédica , Relação Dose-Resposta a Droga , Medicamentos de Ervas Chinesas/economia , Flavonoides/economia , Humanos
20.
Res Microbiol ; 164(8): 848-55, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23811183

RESUMO

Eight-stranded ß-barrel outer membrane proteins can confer bacterial virulence via resistance to host innate defenses. This resistance function of OmpW, which was recently identified as an eight-stranded ß-barrel protein, was investigated in this study. Our results demonstrated that upregulation of OmpW correlated with increased bacterial survival during phagocytosis. Bacterial mutants harboring a deletion of ompW exhibited a significantly increased phagocytosis rate. Both observations suggest that the OmpW protein protects bacteria against host phagocytosis. In addition, expression of ompW is regulated by iron, which implies that the resistance provided by OmpW may be an important factor in iron-related infectious diseases. Furthermore, OmpW has been identified as a protective antigen that protects mice against bacterial infection and is therefore a promising target for vaccine development against infectious diseases.


Assuntos
Antígenos de Bactérias/metabolismo , Proteínas da Membrana Bacteriana Externa/metabolismo , Proteínas de Escherichia coli/metabolismo , Escherichia coli/imunologia , Escherichia coli/fisiologia , Macrófagos/microbiologia , Fagocitose , Fatores de Virulência/metabolismo , Animais , Antígenos de Bactérias/genética , Antígenos de Bactérias/imunologia , Proteínas da Membrana Bacteriana Externa/genética , Proteínas da Membrana Bacteriana Externa/imunologia , Células Cultivadas , Modelos Animais de Doenças , Escherichia coli/genética , Infecções por Escherichia coli/imunologia , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/imunologia , Deleção de Genes , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Ferro/metabolismo , Macrófagos/imunologia , Camundongos , Viabilidade Microbiana , Fatores de Virulência/genética , Fatores de Virulência/imunologia
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