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1.
Crit Rev Food Sci Nutr ; : 1-29, 2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36330603

RESUMO

Mycotoxin contamination has become a challenge in the field of food safety testing, given the increasing emphasis on food safety in recent years. Mycotoxins are widely distributed, in heavily polluted areas. Food contamination with these toxins is difficult to prevent and control. Mycotoxins, as are small-molecule toxic metabolites produced by several species belonging to the genera Aspergillus, Fusarium, and Penicillium growing in food. They are considered teratogenic, carcinogenic, and mutagenic to humans and animals. Food systems are often simultaneously contaminated with multiple mycotoxins. Due to the additive or synergistic toxicological effects caused by the co-existence of multiple mycotoxins, their individual detection requires reliable, accurate, and high-throughput techniques. Currently available, methods for the detection of multiple mycotoxins are mainly based on chromatography, spectroscopy (colorimetry, fluorescence, and surface-enhanced Raman scattering), and electrochemistry. This review provides a comprehensive overview of advances in the multiple detection methods of mycotoxins during the recent 5 years. The principles and features of these techniques are described. The practical applications and challenges associated with assays for multiple detection methods of mycotoxins are summarized. The potential for future development and application is discussed in an effort, to provide standards of references for further research.

2.
Sci Rep ; 12(1): 16851, 2022 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-36207375

RESUMO

In this paper, a special ultrasonic microforming method, Micro Ultrasonic thin Sheetmetal Forming using molten plastic as a flexible punch (short as Micro-USF), was used to conduct micro-punching experiments on stainless steel sheet with thickness of 10 µm and 20 µm. The influence of ultrasonic vibration on forming force and forming quality were investigated. The experimental results showed that the forming force required for punching thin sheet metal decreased gradually as the ultrasonic time or ultrasonic power increased. By applying the ultrasonic vibration effect, the forming force could be decreased dramatically and the maximum value of forming force drop could reach 86%. Moreover, with the application of ultrasonic vibration, the size accuracy and shape accuracy of micro-holes could be increased by 36.92% and 22.65%, but the cross-section quality of micro-holes were not significantly improved.


Assuntos
Aço Inoxidável , Vibração , Fenômenos Mecânicos , Plásticos , Ondas Ultrassônicas
3.
Zhonghua Yi Xue Za Zhi ; 91(48): 3388-92, 2011 Dec 27.
Artigo em Zh | MEDLINE | ID: mdl-22333248

RESUMO

OBJECTIVE: To observe the ratio of Tim-1(+)CD19(+) B cell in the peripheral blood of kidney transplantation recipients and elucidate its functions. METHODS: From December 2009 to June 2010, a total of 35 pairs of kidney transplant recipients were selected and divided into 3 groups: healthy donors as control (n = 35), pre-transplantation (n = 35) and post-transplantation (n = 35). The profiles of Tim-1(+)CD19(+) B cell in kidney transplantation donors and recipients were analyzed and sorted by flow cytometry (FCM). Mixed lymphocyte culture (MLC) was carried out between kidney transplantation donors and recipients. After the additions of Tim-1(+)CD19(+) and Tim-1(-)CD19(+) B cells, there were 3 groups: Tim-1(+), Tim-1(-) and blank. Lymphocyte proliferation and inhibition status were evaluated by propidium iodide uptake and Annexin V binding. And the cytokine levels were detected by FCM. RESULTS: The absolute values of peripheral CD19(+)B cells were (170 ± 90), (202 ± 99), (155 ± 71) cells/µl in the pre-transplantation, post-transplantation and control groups respectively, post-transplantation group were higher than control group (P = 0.0300). The Tim-1(+)CD19(+) cell ratios were (2.20 ± 0.98)%, (35.46 ± 10.66)% and (1.95 ± 0.95)% in three groups. And the differences were statistically significant (both P < 0.01). Tim-1(+)CD19(+) B and Tim-1(-)CD19(+) B cells were added into MLC respectively. The early apoptotic cells of the Tim-1(+) group were higher than those in the Tim-1(-) group [(45.31 ± 12.37)% vs (10.92 ± 2.14)%, P < 0.05] and significantly higher than the blank group [(1.93 ± 0.26)%, P < 0.01]. Late apoptotic and dead cells of the Tim-1(+) group were higher than those in the Tim-1(-) group [(21.32 ± 5.67)% vs (2.32 ± 0.31)%, P < 0.01] and the blank group [(1.27 ± 0.19)%, P < 0.05]. The interleukin 10 levels in MLC supernatant of the Tim-1(+) group were significantly higher than those in the Tim-1(-) group [(5.32 ± 0.37) pg/ml vs (2.46 ± 0.25) pg/ml, P = 0.0001]. However, the interferon-γ levels were lower than those in the Tim-1(-) group [(1.51 ± 0.22) pg/ml vs (4.69 ± 0.32) pg/ml, P = 0.0015]. CONCLUSION: Present in the peripheral blood of kidney transplantation recipients, Tim-1(+)CD19(+) B cell has the capacity of promoting lymphocytic apoptosis. As a new regulatory subset of B cells, it plays important roles in the immune responses of transplantation.


Assuntos
Antígenos CD19/metabolismo , Linfócitos B Reguladores/imunologia , Transplante de Rim/imunologia , Glicoproteínas de Membrana/metabolismo , Receptores Virais/metabolismo , Linfócitos B Reguladores/metabolismo , Estudos de Casos e Controles , Receptor Celular 1 do Vírus da Hepatite A , Humanos , Ativação Linfocitária
4.
Zhonghua Yi Xue Za Zhi ; 91(8): 512-5, 2011 Mar 01.
Artigo em Zh | MEDLINE | ID: mdl-21418849

RESUMO

OBJECTIVE: To find whether the up-regulation of soluble human leucocyte antigen-G5 (sHLA-G5) levels is a new function mechanism of anti-interleukin-2 receptors (anti-IL-2R) monoclonal antibody treatment in kidney transplantation. METHODS: A total of 215 recipients at our centre from January 2006 to December 2007 were divided into antibody use group (n = 141) and antibody non-use group (n = 74) and another healthy group (n = 69). The sHLA-G5 level in peripheral blood was detected by enzyme-linked immunosorbent assay (ELISA). And the expression of HLA-G5 was confirmed by Western blot and Real-time polymerase chain reaction (PCR). RESULTS: sHLA-G5 levels was (56 ± 30) µg/L in using anti-IL-2 receptor monoclonal antibody before transplantation, It was higher than that before use antibody [(34 ± 20) µg/L], also higher than healthy group [(35 ± 17) µg/L] and antibody non-use group [(36 ± 19) µg/L, P < 0.05, respectively]. At Day 1, Day 4, Week 1, Week 2 post-transplantation, the level of sHLA-G5 of recipients with antibody use was significantly higher than that of those with antibody non-use. The values were as follows: (95 ± 35) µg/L vs (54 ± 16) µg/L, (131 ± 24) µg/L vs (75 ± 22) µg/L, (167 ± 44) µg/L vs (62 ± 17) µg/L, (172 ± 35) µg/L vs (45 ± 16) µg/L (all P < 0.01). And the results of Western blot and RT-PCR corresponded to those of ELISA. CONCLUSION: The preoperative use of first dose of anti-IL-2R monoclonal antibodies results in the up-regulated level of sHLA-G5. Thus it is beneficial for protecting the kidney survival and reducing the risks of acute rejection.


Assuntos
Anticorpos Monoclonais/farmacologia , Antígenos HLA-G/metabolismo , Transplante de Rim , Receptores de Interleucina-2/imunologia , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Regulação para Cima , Adulto Jovem
5.
Cell Death Dis ; 12(6): 568, 2021 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-34078881

RESUMO

GATA2, a key transcription factor in hematopoiesis, is frequently mutated in hematopoietic malignancies. How the GATA2 mutants contribute to hematopoiesis and malignant transformation remains largely unexplored. Here, we report that Gata2-L359V mutation impeded hematopoietic differentiation in murine embryonic and adult hematopoiesis and blocked murine chronic myeloid leukemia (CML) cell differentiation. We established a Gata2-L359V knockin mouse model in which the homozygous Gata2-L359V mutation caused major defects in primitive erythropoiesis with an accumulation of erythroid precursors and severe anemia, leading to embryonic lethality around E11.5. During adult life, the Gata2-L359V heterozygous mice exhibited a notable decrease in bone marrow (BM) recovery under stress induction with cytotoxic drug 5-fluorouracil. Using RNA sequencing, it was revealed that homozygous Gata2-L359V suppressed genes related to embryonic hematopoiesis in yolk sac, while heterozygous Gata2-L359V dysregulated genes related to cell cycle and proliferation in BM Lin-Sca1+c-kit+ cells. Furthermore, through chromatin immunoprecipitation sequencing and transactivation experiments, we found that this mutation enhanced the DNA-binding capacity and transcriptional activities of Gata2, which was likely associated with the altered expression of some essential genes during embryonic and adult hematopoiesis. In mice model harboring BCR/ABL, single-cell RNA-sequencing demonstrated that Gata2-L359V induced additional gene expression profile abnormalities and partially affected cell differentiation at the early stage of myelomonocytic lineage, evidenced by the increase of granulocyte-monocyte progenitors and monocytosis. Taken together, our study unveiled that Gata2-L359V mutation induces defective hematopoietic development and blocks the differentiation of CML cells.


Assuntos
Fator de Transcrição GATA2/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Animais , Diferenciação Celular/fisiologia , Modelos Animais de Doenças , Fator de Transcrição GATA2/genética , Hematopoese , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mutação
6.
Zhonghua Yi Xue Za Zhi ; 90(36): 2524-7, 2010 Sep 28.
Artigo em Zh | MEDLINE | ID: mdl-21092455

RESUMO

OBJECTIVE: to study the feasibility of human leucocyte antigen-G (HLA-G) as a post-transplantation prognostic biomarker and discuss the correlation of its receptor expression and the mechanisms. METHODS: a total of 215 recipients in our centre from February 2006 to June 2008 were divided into stable kidney function group (n = 173) and acute rejection group (n = 42). The soluble human leucocyte antigen-G5 (sHLA-G5) level in peripheral plasma was detected by ELISA. And the HLA-G receptor ILT-2, KIR2DL4 on T, B, NK lymphocytes were analyzed by flow cytometry (FCM). The sHLA-G5 cutoff level by ROC curve was employed to predict the events of acute post-transplantation rejection. And regression analysis was used to determine the association of sHLA-G5 with acute rejection. RESULTS: an optimal cutoff value of 139.0 microg/L could be defined for sHLA-G5 (sensitivity: 63.6%, specificity: 82.1%, AUC: 0.780). Binary regression analysis showed that sHLA-G5 played an independent role on acute rejection (P = 0.019, OR = 0.039, 95%CI: 2.091 - 5.661). The rate of HLA-G receptor ILT-2 on CD4(+)T cell, CD8(+)T cell and B cell in acute rejection group was statistically lower than that in stable kidney function group (21% ± 7% vs 52% ± 17%, 23% ± 6% vs 39% ± 16%, 21% ± 7% vs 39% ± 16%, all P < 0.05). The expression of KIR2DL4 on NK cells in acute rejection group was statistically lower than that in stable kidney function group (31% ± 10%vs 57% ± 21%, P < 0.05). CONCLUSION: sHLA-G5 level may be predicted for acute rejection with a high sensitivity and specificity. The up-regulated expression of ILT-2 and KIR2DLT may contribute to immunology tolerance in peripheral circulation.


Assuntos
Antígenos HLA/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Transplante de Rim/imunologia , Receptores Imunológicos/imunologia , Adulto , Antígenos CD/análise , Antígenos CD/imunologia , Feminino , Sobrevivência de Enxerto , Antígenos HLA/análise , Antígenos HLA-G , Antígenos de Histocompatibilidade Classe I/análise , Humanos , Tolerância Imunológica , Receptor B1 de Leucócitos Semelhante a Imunoglobulina , Masculino , Pessoa de Meia-Idade , Receptores Imunológicos/análise , Receptores KIR2DL4/análise , Receptores KIR2DL4/imunologia , Receptores KIR2DL5 , Sensibilidade e Especificidade
7.
Zhonghua Yi Xue Za Zhi ; 90(4): 241-4, 2010 Jan 26.
Artigo em Zh | MEDLINE | ID: mdl-20356537

RESUMO

OBJECTIVE: To investigate the expression of non-classical major histocompatibility complex (MHC)-I molecule, human leucocyte antigen (HLA) G, including membrane-bound HLA-G (mHLA-G), intracellular HLA-G (iHLA-G) and soluble HLA-G (sHLA-G), in peripheral blood of surviving kidney transplantation recipients and understand the relevance between HLA-G and the function of transplanted organ, as well as the onset of acute rejection. METHODS: A longitudinal study was performed on 175 kidney transplantation recipients. Three groups were involved in this study, including acute rejection group (n = 36), function stable group (n = 139) and healthy control group (n = 30). The expression of mHLA-G1 and iHLA-G1 in the T lymphocytes of peripheral blood was detected by flow cytometry analysis and the sHLA-G5 level detected by ELISA. RESULTS: The average rate of CD4(+)mHLA-G1(+), CD8(+)mHLA-G1(+), CD4(+)iHLA-G1(+), CD8(+)iHLA-G1(+) in T lymphocytes of healthy control group was 0.43% +/- 0.19%, 1.23% +/- 0.41%, 27% +/- 13% and 36% +/- 14% respectively. That of acute rejection group was 0.57% +/- 0.34%, 1.31% +/- 0.56%, 26% +/- 8% and 37% +/- 17%; that of function stable group was 0.61% +/- 0.43%, 1.39% +/- 0.47%, 26% +/- 9% and 37% +/- 17% respectively. There was no significant difference among the three groups (all P > 0.05). The average of sHLA-G5 levels in plasma of control group was (25 +/- 14) ng/ml, acute rejection group (24 +/- 15) ng/ml (pre-operative) and (34 +/- 21) ng/ml (post-operative), function stable group (25 +/- 11) ng/ml (pre-operative) and (56 +/- 32) ng/ml (post-operative). There was no significant difference among the three groups (pre-operative, P > 0.05). The average of sHLA-G5 levels in plasma of function stable group was higher than that of acute rejection group (post-operative, P < 0.05). CONCLUSION: There is a subset of CD4(+)HLA-G1(+) and CD8(+)HLA-G1(+)T lymphocytes with low percentage in peripheral blood of those surviving kidney transplantation recipients. The expressions of mHLA-G1 and iHLA-G1 have no relevance with the onset of acute rejection. sHLA-G5 is correlated with acute rejection in peripheral blood of surviving transplantation recipients.


Assuntos
Rejeição de Enxerto , Antígenos HLA/sangue , Antígenos de Histocompatibilidade Classe I/sangue , Transplante de Rim , Adolescente , Adulto , Feminino , Antígenos HLA-G , Humanos , Estudos Longitudinais , Masculino , Adulto Jovem
8.
Biosci Biotechnol Biochem ; 73(12): 2583-8, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19966489

RESUMO

This study researched the effects of chicken meat extract on blood glucose and insulin level, membrane glucose transporter-4 (GLUT4), and tyrosine phosphorylation of insulin receptor substrate-1 (IRS-1) in type 2 diabetic KKAy mice and GK rats. Eight-week-old KKAy mice and GK rats and euglycemic control animals, C57BL/6J mice and Wistar rats, were orally administered a liquid commercial chicken meat extract, BRAND'S Essence of Chicken (BEC), for up to 8 weeks. BEC (1.5 ml/kg) had no effect on blood insulin levels, but significantly lessened the hyperglycemia in the diabetic animals. In the BEC-treated diabetic animals, insulin induced a significant increase in plasma membrane GLUT4 and cytosolic tyrosine-phosphorylated IRS-1, indicating that it attenuates insulin resistance. The present findings are the first demonstration of the hypoglycemic action of a dietary protein, and they lend credence to the reported benefits of using chicken meat as a source of protein in the dietary management of diabetic individuals.


Assuntos
Glicemia/metabolismo , Galinhas , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/dietoterapia , Proteínas Alimentares/farmacologia , Hiperglicemia/dietoterapia , Carne , Animais , Diabetes Mellitus Tipo 2/metabolismo , Teste de Tolerância a Glucose , Hiperglicemia/complicações , Insulina/sangue , Resistência à Insulina , Masculino , Camundongos , Fosforilação/efeitos dos fármacos , Ratos , Tirosina/metabolismo
9.
Urol Int ; 83(2): 200-5, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19752617

RESUMO

INTRODUCTION: Aristolochic acid contained in Chinese herbs has been proved to be nephrotoxic and carcinogenic. Immunosuppression is associated with an increased risk of developing malignancies. What will be the result if these two significant risk factors are concomitantly present in transplanted patients with aristolochic acid nephropathy (AAN)? PATIENTS AND METHODS: A 2-center cohort of 1,612 renal transplant recipients was studied retrospectively from January 1998 to December 2006. We performed an evaluation of the database and review of the charts and pathology reports of these recipients. RESULTS: Kidney transplantations were performed in 17 patients with AAN. Nine (52.9%) of these recipients developed urothelial carcinoma (UC), compared with a 0.46% prevalence of urinary tract tumors among kidney-transplanted patients in China. Eight cases (88.9%) involved the upper urinary tract (bilateral, 3 cases, 37.5%; unilateral, 5 cases, 62.5%). All patients underwent surgical treatment. Six patients (75%) had recurrence during the follow-up period. Three patients died within a mean of 20 months after tumor excision. CONCLUSIONS: The risk for UC is distinctly increased in patients with AAN after transplantation. Regular screening for early detection of malignancy is mandatory.


Assuntos
Ácidos Aristolóquicos/efeitos adversos , Carcinoma de Células de Transição/etiologia , Falência Renal Crônica/induzido quimicamente , Falência Renal Crônica/complicações , Neoplasias Renais/etiologia , Transplante de Rim , Complicações Pós-Operatórias/etiologia , Adulto , Idoso , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
10.
Environ Sci Pollut Res Int ; 26(8): 7476-7485, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30659484

RESUMO

Sediment resuspension has been recognized as a crucial internal process in aquatic ecosystems. However, there is still a lack of reliable measuring methods due to the complex hydrodynamic conditions in large shallow eutrophic lakes. In this study, sequential sediment traps (SST) and instantaneous multiple point (IMP) methods were compared at 6 sites located in the littoral zone of Zhushan Bay in Lake Taihu. Results show that the average resuspension rates (RRs) estimated using the IMP method at sites 1 to 6 were 266.39, 272.79, 235.17, 254.95, 392.25, and 483.85 g·m-2d-1, respectively. While the RRs estimated using the SST method were 195.16, 236.99, 116.76, 156.23, 389.53, and 509.85 g·m-2d-1, respectively. In wind-disturbed areas, both methods were suitable for RR analysis in large and shallow eutrophic lakes and SST provides high-resolution temporal RR estimations. However, in the areas with cyanobacterial blooms and vegetation cover, the IMP method overestimated the RR. Therefore, SST was more suitable across different conditions in large and shallow eutrophic lakes, providing a simple, accurate, and high-resolution temporal estimation of RR, while furthering our understanding of lake evolution processes.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos/análise , Lagos/química , Vento , China , Ecossistema , Ecótipo , Eutrofização , Hidrodinâmica
11.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 28(8): 683-5, 2008 Aug.
Artigo em Zh | MEDLINE | ID: mdl-18928088

RESUMO

OBJECTIVE: To explore the mechanism of Chinese medicinal therapy for cooling blood and removing stasis (CBRS) in treating psoriasis of blood-heat syndrome type by observing its clinical efficacy and impact on serum level of cytokines. METHODS: Changes of psoriasis area and severity index (PASI) scores, scores of syndrome and serum levels of tumor necrosis factor alpha (TNF-alpha, Th1 cytokine) and interleukin-10 (IL-10, Th2 cytokine) in 32 psoriatic patients before and after treatment were observed. RESULTS: The total effective rate after 4 weeks of treatment and 8 weeks of treatment was 65.63% (21/32 cases) and 75.00% (24/32 cases) respectively. Scores of PASI and syndrome all improved after treatment (P < 0.05). And comparison of TNF-alpha level before and after treatment also showed significant difference (P < 0.05) , whereas that of IL-10 was insignificant (P > 0.05). Moreover, a positive correlation was found between PASI scores and secreting level of TNF-alpha in patients with psoriasis (r = 0.3709, P < 0.05). CONCLUSION: Chinese therapy for CBRS could play its effect in treating psoriasis by way of reducing TNF-alpha level.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Psoríase/tratamento farmacológico , Psoríase/imunologia , Células Th1/imunologia , Células Th2/imunologia , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Citocinas/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Psoríase/sangue , Psoríase/patologia , Adulto Jovem
12.
Zhong Xi Yi Jie He Xue Bao ; 6(2): 190-3, 2008 Feb.
Artigo em Zh | MEDLINE | ID: mdl-18241657

RESUMO

OBJECTIVE: To explore the effects of Liangxue Huayu therapy (LXHYT), a traditional Chinese herbal therapy for cooling blood and dissipating blood stasis, on rat model of experimental autoimmune thyroiditis (EAT) and its impact on tumor necrosis factor-alpha and interleukin-10 mRNA expressions in peripheral blood mononuclear cells. METHODS: Forty Wistar rats were randomly divided into five groups: normal control group, untreated EAT group, cyclosporine A (CyA)-treated group, Tripterygium glycosides-treated group and Liangxue Huayu Recipe (LXHYR)-treated group. The interventions were given by gavage to the rats in different groups once a day. All rats were sacrificed after 4-week treatment, and the level of serum thyroglobulin antibodies (TgAb) and the changes of histological grade of thyroid specimen were assessed by blind evaluation. Expressions of tumor necrosis factor-alpha (TNF-alpha) and interleukin-10 (IL-10) mRNAs in peripheral blood mononuclear cells were assessed by real-time reverse transcription polymerase chain reaction method. RESULTS: There was a significant increase in the serum TgAb level and severe inflammatory infiltration in the untreated group. Expression of TNF-alpha mRNA in peripheral blood mononuclear cells was increased, while the expression of IL-10 mRNA was decreased in the untreated group (P<0.01). Compared with the untreated group, CyA, Tripterygium glycosides and LXHYF could decrease the serum TgAb level (P<0.05), but the three interventions showed no significant improvement in thyroid inflammation (P>0.05). TNF-alpha mRNA expression was decreased, while IL-10 mRNA expression was increased as compared with the untreated group (P<0.05). CONCLUSION: LXHYT can decrease the serum TgAb level and recover the balance of Th1/Th2. This may provide an experimental basis for further research of assessing the antipsoriatic effect of Chinese herbal drugs with a rat model of EAT as an alternative model of psoriasis in vivo.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Interleucina-10/sangue , Fitoterapia , Tireoidite Autoimune/tratamento farmacológico , Fator de Necrose Tumoral alfa/sangue , Animais , Interleucina-10/genética , Leucócitos Mononucleares/metabolismo , Masculino , RNA Mensageiro/sangue , RNA Mensageiro/genética , Distribuição Aleatória , Ratos , Ratos Wistar , Tireoidite Autoimune/sangue , Fator de Necrose Tumoral alfa/genética
13.
Huan Jing Ke Xue ; 39(3): 1180-1187, 2018 Mar 08.
Artigo em Zh | MEDLINE | ID: mdl-29965462

RESUMO

Submerged macrophytes are an important component of aquatic ecosystems. During the growing period, submerged macrophytes can absorb nitrogen and phosphorus nutrients to reduce pollution loadings. Shoots of submerged macrophytes can also promote the adhesion of suspended substances in water, reducing the turbidity. The release of nutrients in sediments can be suppressed by its root system, and the resuspension of sediments caused by disturbance of winds and waves can also be resisted. The role of submerged macrophytes in ecological restoration of eutrophic lakes has attracted widespread attention. In 1960, the submerged plants Vallisneria natans and Potamogeton malaianus had been the dominant species in East Taihu. However after 2002, Nymphoides peltatum, Elodea nattalii, P. malaianus, etc. have gradually taken over the dominant roles along with significant elevations of nitrogen and phosphorus levels. Nutrients in water are not the only key factors causing eutrophication of water bodies; the nutrient source for submerged plant growth affect both the purification efficiency and the photosynthetic characteristics of submerged macrophytes. Excessive nitrogen and phosphorus concentrations can inhibit the photosynthetic physiological activities of submerged macrophytes, affecting the succession of aquatic vegetation. In addition, under high nutrient conditions, the competition from periphytic algae and planktonic algae may also directly poison submerged macrophytes, leading to its degradation and disappearance. Systematic studies on the regulation and photosynthetic fluorescence response mechanism of submerged macrophytes to varied nutrient loadings are helpful in revealing their relationships. The seedlings of submerged macrophyte V. natans were transplanted in a laboratory mesocosm to study the effect of nutrient loadings on its regulation of water nitrogen and phosphorus. Three nitrogen and phosphorus loadings from low, medium, and high levels derived from nitrate, ammonium, and phosphate were setup as the aquatic medium for the plant growth. Twelve harvests were carried out to determine the evolution of nutrient removal performance of V. natans. Its photosynthetic fluorescence characteristics were measured by a pulse-amplitude modulated fluorometer (Diving-PAM). Results showed that the nitrogen and phosphorus adsorption abilities of V. natans were gradually enhanced with the increase of nutrient concentrations in the range of TN ≤ 12 mg·L-1 and TP ≤ 1.0 mg·L-1. In the treatment of high nutrient concentrations (TN=12 mg·L-1 and TP=1.0 mg·L-1), the removal rates of nitrogen and phosphorus reached more than 95%. V. natans preferentially absorbed ammonium nitrogen when its concentration was high. The medium nutrient concentrations (TN:8-12 mg·L-1 and TP:0.6-1.0 mg·L-1) did not significantly affect the Fv/Fm ratio of leaves. However, the low nutrient concentrations (TN=3 mg·L-1 and TP=0.3 mg·L-1) could improve the Fv/Fm ratio of leaves and were beneficial for the growth of V. natans. The inhibition of photosynthetic activity and light tolerance were enhanced with the increase in nutrient concentrations. The photosynthetic activity of V. natans gradually recovered with no significant changes in the capacity for light harvesting, when the nutrient concentrations gradually decreased in the water. Our results indicate that the high nitrogen and phosphorus loadings indeed hamper the photosynthetic capacity, which may subsequently restrain the maintenance of the dominance of V. natans in the submerged macrophyte communities.


Assuntos
Hydrocharitaceae/metabolismo , Nitrogênio/análise , Fósforo/análise , Poluentes da Água/análise , Água/química , Fluorescência , Fotossíntese
14.
Endocrinology ; 148(12): 5925-32, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17823251

RESUMO

The present study investigated the hypoglycemic action of des-aspartate-angiotensin I (DAA-I), a metabolite of angiotensin I, in two animal models of type 2 diabetes. The rationale was based on our earlier studies demonstrating that DAA-I acts on the angiotensin AT(1) receptor and exerts responses opposing those of angiotensin II and on recent reports that curtailment of angiotensin II formation by angiotensin converting enzyme inhibitors and blockade of the AT(1) receptor attenuate hyperglycemia in type 2 diabetics and diabetic animals. Diabetic KKAy mice and GK rats were administered orally (by gavage) one of the following doses of DAA-I: 400, 600, or 800 nmol/kg.d for 4 and 6 wk, respectively. Control diabetic animals were similarly administered water. Blood glucose of each animal was determined fortnightly by oral glucose tolerance test and blood insulin on the last day of treatment. Animals were killed, and the levels of plasma membrane glucose transporter-4 and cytosolic tyrosine-phosphorylated insulin receptor substrate-1 in hind limb skeletal muscles were determined by Western blot in insulin-challenged and nonchallenged animals. Orally administered DAA-I had no effect on blood insulin level but exerted dose-dependent hypoglycemic action in KKAy mice and GK rats after 4 and 6 wk of treatment, respectively. At the maximal effective dose of 600 nmol/kg, insulin induced a significant increase in plasma membrane glucose transporter-4 and cytosolic tyrosine-phosphorylated insulin receptor substrate-1. These findings show that DAA-I is not an insulin secretagogue and exerts hypoglycemic action by attenuating insulin resistance, the first such demonstration indicating that the nonapeptide is involved in glycemic regulation.


Assuntos
Angiotensina I/farmacologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Transportador de Glucose Tipo 4/metabolismo , Hipoglicemiantes/farmacologia , Angiotensina I/administração & dosagem , Angiotensina I/análogos & derivados , Animais , Glicemia/metabolismo , Western Blotting , Peso Corporal/efeitos dos fármacos , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Teste de Tolerância a Glucose , Hipoglicemiantes/administração & dosagem , Imunoprecipitação , Insulina/sangue , Resistência à Insulina , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Músculo Esquelético/metabolismo , Fosfodiesterase I/metabolismo , Distribuição Aleatória , Ratos , Ratos Wistar
15.
Huan Jing Ke Xue ; 38(1): 95-103, 2017 Jan 08.
Artigo em Zh | MEDLINE | ID: mdl-29965035

RESUMO

To reveal the spatiotemporal characteristics of nutrients in the deposition process of suspended solids in lakeside zone,in situ deposition tests were performed in the western lakeside of Taihu Lake,and the contents of TP,TN,NH4+-N and NO3--N were measured and analyzed.The results showed that the deposition fluxes in the western lakeside of Taihu Lake ranked as follows:artificial reed areas >non-vegetation nearshore areas >natural reed areas >non-vegetation offshore areas,with their average values of (1383.40±925.60),(1208.67±743.50),(278.72±142.53),(245.58±154.25) g·(m2·d)-1,respectively.From the 6th day,the deposition volume steadily increased,with the deposition rate larger than the decomposition rate.Through the 15-day continuous in situ observation,the content of TP in nearshore zone was 2-3 folds larger than that of offshore zone,and the content of NH4+-N was significantly different from that of NO3--N in the settlement bottle (P<0.01).The deposition volume was significantly and positively correlated to both TN and NH4+-N contents in the water column (P<0.01,n=42),suggesting that the TN and NH4+-N contents in the overlying water increased with the deposition fluxes.The correlation coefficient between TN and NH4+-N was 0.84,implicating that the increase of deposition flux may accelerate the mutual transformation between different forms of nitrogen.These findings should be taken into account in the current control of black blooms and nutrient management in Taihu Lake.

16.
Cancer Immun ; 6: 7, 2006 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-16594646

RESUMO

CT10/MAGE-C2 is a recently identified antigen that, typically of cancer/testis (CT) antigens, can be found in various malignant tumors and in normal adult testis. As with many other CT antigens, our knowledge is based mainly on mRNA expression data. In the present study, we describe the generation of mAbs to CT10/MAGE-C2 for the analysis of its protein expression. Newly generated clones were chosen based on their reactivity in ELISA, immunoblotting, and immunohistochemistry (IHC). Emphasis was put on the reactivity of newly generated reagents on formalin-fixed, paraffin-embedded tissue to ensure their applicability to archival material. Eventually we selected two clones, LX-CT10.5 and LX-CT10.9, that showed intense reactivity to CT10/MAGE-C2 protein and CT10/MAGE-C2 mRNA-positive cell lines, but no cross-reactivity with other CT antigens. Both mAbs show superior staining characteristics in IHC and are applicable to frozen and paraffin sections. In testis, CT10/MAGE-C2 displays the typical CT pattern with regard to staining of germ cells, which is intense during the early maturation stages. In tumors, we analyzed a limited number of cases displaying the typical heterogeneous CT expression pattern. Interestingly, immunoreactivity was seen solely in the nucleus: No staining was seen in the cytoplasm of tumor cells.


Assuntos
Anticorpos Monoclonais/imunologia , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/imunologia , Animais , Antígenos de Neoplasias , Núcleo Celular , Citoplasma , Ensaio de Imunoadsorção Enzimática , Perfilação da Expressão Gênica , Humanos , Hibridomas , Imuno-Histoquímica , Masculino , Melanoma/patologia , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias Cutâneas/patologia , Baço/citologia , Células Tumorais Cultivadas
17.
Burns ; 32(8): 986-91, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17045747

RESUMO

Although many models of electrical injury have been established, none of them are completely typical of the clinical features of electrical injury. As a result, research based on these models were incapable of explaining many clinical phenomena such as continuous tissue necrosis and also were unable to cope with high ratio of amputation of extremities. In order to investigate the mechanism of electrical injuries and better model the condition with similar clinical characteristics we developed a new model. Seventy-five New Zealand rabbits were employed in this study, of them 45 were used in a preliminary experiment including the selection of the size of electrode plate area, damaged extent, time length of electrical injury and interval length between two injuries and so on. Another 30 rabbits were equally divided into five groups with electrical injury times of 6, 12, 18, 24 and 30 cycles, respectively. Observations were made using clinical anatomical exploration, with quantification using an IDBI scale on the 2nd, 8th, 24th, 48th hours and 5th, 15th days, and TC-99m-DMP isotope scanning and gamma photography at 2nd hour and 5th day in post-injury, respectively. The results showed the effective electric field strength was 17,000 V/m, mean current intensity was 554 mA, average current density was 137 mA/cm(2) beneath the small electrode plate with 21 mA/cm(2) beneath big one, and average increase of tissue temperature was 1.73 degrees C during injury process which excluded the possibility of thermal injury. One single wound injury beneath the small plate of the experimental rabbits with loss of injured extremities from 5th to 15th post-injury days in groups 3-5 and obviously progressive tissue necrosis in and outside the wounds were obtained. A series of electrical injured models from mild, moderate, severe, extra severe, and destructive which was exactly similar to the clinical features of electrical injury cases was established.


Assuntos
Queimaduras por Corrente Elétrica/patologia , Músculo Esquelético/patologia , Pele/patologia , Animais , Queimaduras por Corrente Elétrica/diagnóstico por imagem , Modelos Animais de Doenças , Músculo Esquelético/diagnóstico por imagem , Necrose , Compostos de Organotecnécio , Coelhos , Cintilografia , Pele/diagnóstico por imagem , Compostos de Sulfidrila
19.
J Environ Sci (China) ; 17(2): 245-8, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16295898

RESUMO

The exhaust gas recirculation (EGR), coupled with a high-collection efficiency particulate trap to simultaneously control smoke and NOx emissions from diesel engines were studied. This ceramic trap developed previously provided the soot cleaning efficiency of 99%, the regeneration efficiency reaches 80% and the ratio of success reaches 97%, which make EGR used in diesel possible. At the presence of EGR, opening of the regeneration control valve of the trap was over again optimized to compensate for the decrease of the oxygen concentration in the exhaust gas resulted from EGR. The results indicated the cleaning efficiency and regeneration performance of the trap were maintained at the same level except that the back pressure increased faster. A new EGR system was developed, which is based on a wide range oxygen (UEGO) sensor. Experiments were carried out under steady state conditions while maintaining the engine speed at 1600 r/min, setting the engine loads at 0%, 25%, 50%, 75% and 100% respectively. Throughout each test the EGR rate was kept at nine different settings and data were taken with the gas analyzer and UEGO sensor. Then, the EGR rate and engine load maps, which showed the tendencies of NOx, CO and HC emissions from diesel engine, were made using the measured data. Using the maps, the author set up the EGR regulation, the relationship between the optimal amounts of EGR flow and the equivalence ratio, sigma, where sigma = 14.5/AFR.


Assuntos
Poluição do Ar/prevenção & controle , Óxidos de Nitrogênio/isolamento & purificação , Emissões de Veículos/análise , Emissões de Veículos/prevenção & controle , Carbono/análise , Veículos Automotores , Óxidos de Nitrogênio/análise , Oxigênio/análise , Tamanho da Partícula
20.
Eur J Pharmacol ; 768: 173-81, 2015 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-26524410

RESUMO

DAA-I (des-aspartate-angiotensin I), an endogenous angiotensin, had been shown earlier to ameliorate animal models of cardiovascular diseases via the angiotensin AT1 receptor and prostaglandins. The present study investigated further the action of DAA-I on the release of PGE2, PGI2, PGF2α and TXA2 in HUVEC. 10(-11)-10(-8)M DAA-I and 15min incubation specifically released PGE2 and PGI2. The release was inhibited by losartan and indomethacin but not by PD123319 and NS398 indicating that the angiotensin AT1 receptor and COX-1 mediate the release. At concentrations higher than 10(-7)M, DAA-I mimics the action of angiotensin II by releasing TXA2 but had no effect on the production of PGF2α. At similar concentrations and 4h incubation, DAA-I increased the release of the 4 prostaglandins via the angiotensin AT1 receptor and COX-2, again mimicking the action of angiotensin II. HUVEC that were preincubated with DAA-I or angiotensin II, released similar profiles of prostaglandins when incubated with arachidonic acid after the angiotensin had been washed off. We postulate that the internalized DAA-I/receptor complex remains active and mediates the conversion of arachidonic acid to the respective prostaglandins. The release of PGE2 and PGI2 via the angiotensin AT1 receptor and COX-1 is a novel specific action of DAA-I and is likely responsible for its beneficial effects seen in earlier studies. This specific action is definable as a biased agonism of the angiotensin AT1 receptor, which identifies DAA-I as a novel biased agonist and potential therapeutic that is able to produce specific prostaglandins at nanomolar concentrations.


Assuntos
Angiotensina I/análogos & derivados , Dinoprostona/metabolismo , Epoprostenol/metabolismo , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Receptor Tipo 1 de Angiotensina/agonistas , Receptor Tipo 1 de Angiotensina/metabolismo , Angiotensina I/farmacologia , Ácido Araquidônico/farmacologia , Humanos , Fatores de Tempo
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