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1.
Biomed Pharmacother ; 158: 114190, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36916441

RESUMO

Securinega alkaloids are indolizidine alkaloids extracted from the leaf and root of an Asian plant, Securinega suffruticosa. Since its discovery in 1956 by Russian scientists, numerous studies have been conducted on securinega alkaloids and their derivatives as bioactive agents. In this review, published work on the bioactivities and the mechanism of action of securinega alkaloids and their derivatives is addressed. References were obtained through for example, the Web of Science, Science Direct, Pubmed and Google Scholar. Research into the synthesis of securinega alkaloids and their derivatives lacking activity assessment has been excluded. Comprehensive reviews show that securinega alkaloids and their derivatives exhibit a wide range of activities among which antineoplastic activity and nervous system related activity were reported although the mechanisms of action remain in part unknown. The other activities such as induction of differentiation, reversal of multi-drug resistance, cardiovascular system related activity, anti-inflammatory, adjuvant agent and anti-pathogenic activity are also reviewed. We found that modification at the C12, C14, and C15 sites on securinine improves the antitumor activity, while derivatives in which a bivalent mimetic is linked to the C15 site is beneficial for differentiation induction activity and reversal of P-glycoprotein mediated drug resistance. The most related pathways involved in the bioactivity of securinega alkaloids and their derivatives are JAK/STAT, PI3K/AKT/mTOR and MAPK. A perspective and expectation concerning the research of securinega alkaloids is presented at the end of this article. This review indicates directions around which constant endeavor could be valuable for researchers in the near future.


Assuntos
Alcaloides , Securinega , Fosfatidilinositol 3-Quinases , Alcaloides/farmacologia , Alcaloides/metabolismo
2.
Front Surg ; 9: 841302, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35465440

RESUMO

Objective: To establish a simple and practical model for super-microsurgery training using the middle caudal arteries of Kunming mice. Methods: A ⊔-shaped incision was made approximately 1 cm from the root of the tail in the mouse, and the skin, together with the subcutaneous tissue, was turned up into a rectangular shape to the opposite side with exposure of the mouse middle caudal artery and the accompanying veins. The artery was freed for approximately 1 cm in length. The middle caudal artery was cut transversely at the site, and then the severed middle caudal artery was anastomosed end-to-end using 12-0 microsutures in the order of 6, 12, 3, and 9 o'clock with four stitches. Results: The mouse caudal artery had a constant anatomical location accompanied by a vein. The immediate postoperative patency after vascular anastomosis was 100% (15/15) in all mouse models, the postoperative patency was 100% (5/5), 80% (4/5), and 75% (3/4) at 24 h, 3 days, and 1 week postoperatively, respectively. The outer diameter of the mouse middle caudal artery was 0.2 ~ 0.3 (0.22 ± 0.03) mm. The vascular anastomosis time was 6.5 ~ 15 (11.0 ± 2.5) min. Conclusion: The mouse middle caudal artery was superficially located and anatomically constant, making it easy to be located and exposed. The small size of the opening made it suitable for establishing a useful model for training in super-microsurgery vascular anastomoses.

3.
J Orthop Surg Res ; 16(1): 261, 2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33853660

RESUMO

BACKGROUND: Many non-union animal models have been developed to explore the problems surrounding fracture healing. However, the existing models are not perfect and cannot satisfy all non-union studies. This study aimed to make a non-union model of the tibia in rats by cauterization of the posterior of 2 mm on both sides of the fracture end after open osteotomy of the tibia and fixing the fractured tibia with a Kirschner wire 0.8 mm in diameter. METHODS: For this study, 96 female adult Sprague-Dawley (SD) rats were used. The rats underwent surgery to produce a tibial open fracture and were fixed with a 0.8-mm diameter Kirschner wire. In 48 of the rats, the periosteum proximal and distal to the fracture end was cauterized. RESULTS: At 2, 4, 6, and 8 weeks after surgery, radiological and histological analysis showed typical physiological healing in the control group, and the healing rate was 100% at 6 weeks. But the non-union group was characterized by resorption of the fracture ends with few callus formations and no bridging callus formation, and the healing rate was 0% at 8 weeks. CONCLUSIONS: This method represents a reproducible model to create atrophic non-unions. This model provides a new option for studying the basic healing mechanisms and evaluating new therapies for bone regeneration and treatment of non-unions.


Assuntos
Cauterização/métodos , Fixação Interna de Fraturas/métodos , Consolidação da Fratura/fisiologia , Fraturas não Consolidadas/enzimologia , Fraturas não Consolidadas/fisiopatologia , Fraturas não Consolidadas/cirurgia , Tíbia/fisiopatologia , Fraturas da Tíbia/fisiopatologia , Fraturas da Tíbia/cirurgia , Animais , Regeneração Óssea , Fios Ortopédicos , Modelos Animais de Doenças , Feminino , Ratos Sprague-Dawley
4.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 24(5): 1305-1311, 2016 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-27784347

RESUMO

To investigate the relationship between the LNK(SH2B3) gene single nucleotide polymorphism and risk of acute leukemia (AL) in Chinese population. METHODS: The bone marrow and peripheral blood samples from 31 cases of acute lymphoblastic leukemia, 70 cases of acute myeloid leukemia and 130 healthy persons as the controls were collected. Genotype of LNK SNP Rs3184504(c.784T>C) and Rs78894077(c.724C>T) were determined by PCR-RFLP, and were confirmed by gel electrophoresis and sequencing. The NB4, THP-1 and Raji leukemia cell line models were cultured, the leukemia cell line LNK Rs3184504 and Rs78894077 polymorphism were detected by using direct sequencing. RESULTS: The CC genotype frequencies of Rs3184504 SNP were higher in ALL and AML patients than those in control (P<0.01), but there was no different between the groups in AML and ALL. The frequency of LNK gene Rs3184504 C allele was higher in AL as compared with control (P<0.01). The LNK gene Rs78894077 locus genotype distribution was not significantly different between the AL and the normal control group (P>0.05). Both Rs3184504 and Rs78894077 sites were detected as CC genotype in NB4, THP-1 and Raji cells. CONCLUSION: The persons carrying C allele of LNK gene Rs3184504 are more prone to develop acute leukemia.


Assuntos
Frequência do Gene , Polimorfismo de Nucleotídeo Único , Doença Aguda , Proteínas Adaptadoras de Transdução de Sinal , Alelos , Povo Asiático , Estudos de Casos e Controles , Predisposição Genética para Doença , Genótipo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Leucemia Mieloide Aguda , Reação em Cadeia da Polimerase , Leucemia-Linfoma Linfoblástico de Células Precursoras , Proteínas
5.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 47(6): 969-970, 2016 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-28598133

RESUMO

OBJECTIVES: To observe the clinical efficacy of Qingre Jiedu and Huoxue Huayu Recipe on the prednisone-dependant patients with chronic primary immune thrombocytopenic purpura (CPITP). METHODS: Fifty prednisone-dependant CPITP patients were treated with Qingre Jiedu and Huoxue Huayu Recipe orally one dose a day,the dosage of prednisone for these patients was tapered according to the monitoring result of blood platelet count (BPC).The therapeutic efficacy in these patients was evaluated before and after Chinese medicine treatment over 4 weeks. RESULTS: After the treatment of chinese medicine,BPC was increased from (28.6±22.5) ×109 L-1 to (81.8±56.5)×109 L-1 (P<0.05).The dosage of prednisone was decreased from (28.1±15.2) mg/d to (8.0±9.4) mg/d (P<0.05).Complement response,response and no response rate were 2%,10% and 88% before Chinese medicine treatment,which were 30%, 46% and 24% after Chinese medicine treatment,respectively (P<0.05). CONCLUSIONS: Qingre Jiedu and Huoxue Huayu Recipe could be effective in the treatment of prednisone-dependant patients with CPITP,and could decrease the dosage of prednisone.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Prednisona/administração & dosagem , Púrpura Trombocitopênica Idiopática/tratamento farmacológico , Quimioterapia Combinada , Humanos , Prednisona/uso terapêutico
6.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 23(5): 1513-6, 2015 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-26524068

RESUMO

Almost all patients with multiple myeloma (MM) have chromosomal translocation which can result in genetic variation. There are mainly five types of chromosomal translocations, involving the IGH gene translocation to 11q13 (CCND1), 4p16 (FGFR/MMSET), 16q23 (MAF), 6p21 (CCND3) and 20q11 (MAFB). It is possible that all IGH translocations converge on a common cell cycle signal pathway. Some MM develops through a multistep transformation from monoclonal gammopathy of undetermined significance (MGUS) to smoldering MM (SMM) and eventually to MM and plasma cell leukemia (PCL). Similarly to what Darwin proposed in the mid-19th century-random genetic variation and natural selection in the context of limited resources, MM clonal evolution follow branching and nonlinear mode. The failure of MM treatment is usually related with the minimal subclone which is hardly found at newlydiagnosed.


Assuntos
Evolução Clonal , Mieloma Múltiplo/genética , Translocação Genética , Ciclina D1 , Genes de Cadeia Pesada de Imunoglobulina , Humanos
7.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 23(4): 915-8, 2015 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-26314417

RESUMO

Recently, chimeric antigen receptors T cells (CAR T) have made a breakthrough in the treatment of lymphoma and leukemia, open a new path for the tumor cellular immunetherapy. It is the key for CAR T to take the gene which can identify the CD19 antigen of lymphoblastic leukemia into lymphocytes, enable it to kill leukemia cells with specific cell-surface loci. The same principle also applies to other aspects, if we find specific target genes of lymphocytes. Recent studies have found that high mobility group protein N2 (high mobility group chromosal protein N2, HMGN2) is the excellent target of tumor-associated antigen in lymphocytes, is the antitumor effector molecule of CD8(+) T cells, which has the ability of trends and specific identify/binding in myeloid leukemia, breast cancer, cervical cancer and other tumor cells. HMGN2 is expected to be used for the preparation of specific identification of tumor lymphocytes and to treat more leukemia and tumors. This article focuses on the strucure and function of HMGN and the chemotaxis and antitumor effect of HMGN2 in leukemia and tumors.


Assuntos
Leucemia , Neoplasias , Antígenos CD19 , Antígenos de Neoplasias , Linfócitos T CD8-Positivos , Proteína HMGN2 , Humanos , Imunoterapia , Receptores de Antígenos de Linfócitos T
8.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 22(6): 1753-6, 2014 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-25543510

RESUMO

Bioengineered T cells, which are the genetically manipulated T cells to express chimeric antigen receptor T Cell (CAR T) against leukemia-associated specific antigens, were applied to treat acute and chronic lymphocytic leukemia with CAR T. CAR T cells combined with cell-surface binding site and anti-CD19 chimeric antigen receptor can treat diseases through T cells transfection. CAR T cells can recognize the CD19 antigen on B cells with specific cell-surface loci. CAR T cells can proliferate by 1000 times and differentiate in vivo by the CD19 antigen stimulation, therefore, kill the acute and chronic lymphocytic leukemia cells effectively. This article briefly reviews the CAR T cells and the effect of CAR T cells on acute and chronic lymphoblastic leukemia.


Assuntos
Leucemia-Linfoma Linfoblástico de Células Precursoras/imunologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Receptores de Antígenos de Linfócitos T/imunologia , Animais , Antígenos CD19 , Linfócitos B , Humanos , Imunoterapia Adotiva , Linfócitos T
9.
J Ind Microbiol Biotechnol ; 41(10): 1581-9, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25139657

RESUMO

A series of site-directed mutant glucose isomerase at tryptophan 139 from Thermoanaerobacterium saccharolyticum strain B6A were purified to gel electrophoretic homogeneity, and the biochemical properties were determined. W139F mutation is the most efficient mutant derivative with a tenfold increase in its catalytic efficiency toward glucose compared with the native GI. With a maximal activity at 80 °C of 59.58 U/mg on glucose, this mutant derivative is the most active type ever reported. The enzyme activity was maximal at 90 °C and like other glucose isomerase, this mutant enzyme required Co(2+) or Mg(2+) for enzyme activity and thermal stability (stable for 20 h at 80 °C in the absence of substrate). Its optimum pH was around 7.0, and it had 86 % of its maximum activity at pH 6.0 incubated for 12 h at 60 °C. This enzyme was determined as thermostable and weak-acid stable. These findings indicated that the mutant GI W139F from T. saccharolyticum strain B6A is appropriate for use as a potential candidate for high-fructose corn syrup producing enzyme.


Assuntos
Aldose-Cetose Isomerases/química , Proteínas de Bactérias/química , Thermoanaerobacterium/enzimologia , Aldose-Cetose Isomerases/genética , Aldose-Cetose Isomerases/isolamento & purificação , Substituição de Aminoácidos , Proteínas de Bactérias/genética , Proteínas de Bactérias/isolamento & purificação , Biocatálise , Estabilidade Enzimática , Glucose/química , Meia-Vida , Xarope de Milho Rico em Frutose/química , Concentração de Íons de Hidrogênio , Cinética , Mutagênese Sítio-Dirigida , Proteínas Mutantes/química , Proteínas Mutantes/genética , Proteínas Mutantes/isolamento & purificação
10.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 22(2): 349-56, 2014 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-24763004

RESUMO

The splenic marginal zone lymphoma (SMZL) is a relatively rare chronic B lymphoproliferative disease, which primarily manifest increase of peripheral blood lymphocyte count and/or scale, and splenomegaly, while the peripheral superficial lymph nodes are often not swollen. Therefore, the splenectomy are usually needed to confirm the diagnosis, but the majority of patients could not accept such management, resulting in early difficult diagnosis. This study was purposed to explore the more prior way for diagnosis based flow cytometry (FCM). Six patients with suspected diagnosis of SMZL were used as research objects, 10 healthy bone marrow donors and 10 cases of chronic lymphocytic leukemia (CLL), 3 cases of hairy cell leukemia (HCL), 3 cases of lymphatic plasma cell lymphoma/Waldenströ's macroglobulinemia (LPL/WM) were selected as control. The immunophenotype of bone marrow cells were analyzed and compared by FCM using a panel of antibodies including CD45, CD5, CD10, CD19, CD20, CD22, CD23, CD25, CD103, CD11c, CD123, κ,λ, Cyclin D1, and combined with bone marrow cell morphology. The results indicated that 6 cases of suspected SMZL showed a large increase of lymphocytes and splenomegaly. Because absence of peripheral lymphadenopathy, 6 patients did not suffer from lymph node biopsy, only 1 patient underwent diagnostic splenectomy. The immunophenotypes of bone marrow in patients and controls were analyzed by FCM, as a result, except for the healthy donors, varying degrees of abnormal mature B cell clones were found in bone marrow of all patients, and the further differentiation from other B-cell tumors was performed through CD5, CD10 expression and combination with other B-cell phenotype. All 6 cases of SMZL patients expressed CD19(+) and CD20(+), but CD10 expression was negative, 4 patients expressed CD5(-), 2 patients expressed CD5(+). The expressions of CD23, CD38, ZAP-70, CD11c, CD103, CD123, Cyclin D1 were negative. The morphological examination of bone marrow cells showed velutinous abnormal lymphocytes. Combined with clinical characteristics, 6 patients were diagnosed as SMZL, 1 patient suffered from splenectomy because of concurrent hypersplenism, and this postoperative pathologic examination confirmed the patient with SMZL. Ten cases of CLL mainly expressed CD5, CD23; 3 cases of HCL had more typical morphology of "hair like" in addition to CD11c, CD103 and CD123 positive; 3 cases of LPL/WM had significantly increased light chain restriction expression, IgM, plasmacytoid lymphocytes. It is concluded that the FCM immunophenotype analysis can be used as a powerful tools for clinical diagnosis of SMZL.


Assuntos
Linfoma de Zona Marginal Tipo Células B/diagnóstico , Transtornos Linfoproliferativos/diagnóstico , Neoplasias Esplênicas/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Linfócitos B , Feminino , Citometria de Fluxo , Humanos , Imunofenotipagem , Masculino , Pessoa de Meia-Idade
11.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 21(5): 1309-12, 2013 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-24156456

RESUMO

Myeloproliferative neoplasms ( MPN ) is a class of clonal hematopoietic stem cell disease. Studies found that the JAK-STAT signaling pathway is closely related to the pathogenesis of MPN. The lymphocyte-specific adaptor protein (LNK) gene negatively regulates Janus kinase-signal transducer and activator of transcription (JAK-STAT) signaling and may play an important role in the pathogenesis of MPN. Especially in JAK2 mutation-negative MPN, LNK gene specific mutations may be the key to cause MPN subtypes. Certain single nucleotide polymorphism of LNK gene regulation of hematopoietic cells in different directions may also be important influence factors of MPN performance for different subtypes. LNK gene functional changes lead to abnormal activation of the JAK-STAT signaling pathway, and may be a new mechanism of MPN. In this review, the role of LNK gene in MPN pathogenesis is briefly summarized.


Assuntos
Mutação , Transtornos Mieloproliferativos/genética , Proteínas/genética , Proteínas Adaptadoras de Transdução de Sinal , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Janus Quinases/metabolismo , Fatores de Transcrição STAT/metabolismo , Transdução de Sinais
12.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 21(2): 517-20, 2013 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-23628067

RESUMO

Signal transducer and activator of transcription 3 (STAT3) take part in cell proliferation, differentiation, survival, apoptosis, transformation, cellular immunity and some other important physiological and pathological processes. Among STAT3 signaling pathways, the JAK-STAT signaling pathway has been comprehensively studied. Abnormal activation of STAT3 is frequently detected in various tumors, and the abnormal activation is closely related with the tumorigenesis. Recent studies have found that mutations and several specific genotypes of single nucleotide polymorphisms in STAT3 gene may be involved in tumor formation, also suggesting the important role of STAT3 in tumor biology. In this review, the role of STAT3 in the development of tumors is briefly summarized.


Assuntos
Neoplasias/patologia , Fator de Transcrição STAT3 , Humanos , Neoplasias/metabolismo , Transdução de Sinais
13.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 20(6): 1427-31, 2012 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-23257447

RESUMO

Objective of this study was to investigate the correlation of body-carried inherited paternal antigens (IPA) in one mother after delivery with pregnancy thrombocytopenia. The changes of platelet (Plt) count in the mother who delivered 2 years ago and her child who is now one year's old were detected, routine tests included Helicobacter pylori, CMV, EBV, parvovirus and other herpes virus's infection were carried out. Eight insertion or deletion sites (InDel) SNP with strong polymorphisms in Chinese population was selected to detect IPA from a genomic library, then primers were designed, the nested PCR and real-time quantitative PCR were used to detect 54 healthy mother-child pairs, the obtained average value was taken as the control, finally two InDel polymorphism sites between mother and child were used to identify the mother/child microchimerism. The IPA of the mother were examined at 4 time points. The results showed that the Plt level of the mother who had suffered thrombocytopenia since 20 weeks after pregnancy reduced to 10 × 10(9)/L. After using gamma globulin, the Plt count increased gradually, but the Plt count decreased rapidly when withdrawal. This patient did not have the infections of virus and Helicobacter pylori. IPA average value of 54 cases were from 10(-5) to 10(-4). At 67 d after delivery, the Plt count of the mother was 14 × 10(9)/L, IPA was 3.45 × 10(-3), which was 30 times higher than the normal. In one month after treatment the IPA was 1.3 × 10(-4) (Plt 256 × 10(9)/L), 5 months later it was 1.2 × 10(-4) (Plt 158 × 10(9)/L), and 6 months later it was 1.5 × 10(-4) (Plt 325 × 10(9)/L). When IPA reached the normal level, the Plt count returned to normal. Her child suffered thrombocytopenia (4 × 10(9)/L) one month after he was born, then recovered after high-dose gamma globulin therapy. It is concluded that abnormal high level IPA may lead to pregnancy thrombocytopenia.


Assuntos
Antígenos/genética , Complicações Hematológicas na Gravidez/genética , Trombocitopenia/etiologia , Trombocitopenia/genética , Quimerismo , Pai , Feminino , Humanos , Recém-Nascido , Masculino , Gravidez
14.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 20(2): 362-7, 2012 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-22541099

RESUMO

Somatic gene V617F mutation in JAK2 is a critical molecular and biological indicator to diagnosis of chronic myeloproliferative disease (MPD). This study was aimed to investigate the genetic background of V617F mutation in 46/1 gene haplotype in Chinese MPD patients, and the frequencies of 46/1 gene haplotype and V617F mutation in three nationalities of Chinese populations. Peripheral blood or bone marrow samples of 150 V617F mutation positive MPD patients, 123 V617F mutation negative MPD patients, 124 healthy Han individuals, 395 healthy Tibetan individuals and 315 healthy Yugu individuals were collected. The allele-specific multiplex PCR method was established, the presence or absence of V617F mutation, the presence or absence of 46/1 haplotype, and the relationship between V617F and 46/1 haplotype were easily identified by agarose gel image. The results showed that the V617F mutation located in the 46/1 haplotype of 88 cases (58.67) among 150 V617F-positive MPD cases. In 814 Chinese healthy individuals including Han, Tibetan, Yugu nationalities, the frequency of the 46/1 gene haplotype was 38.37 without difference in the frequency among different nationalities, and no V617F mutation was found in Chinese healthy populations, The frequency of the 46/1 gene haplotype was 43.09 in V617F mutation negative MPD patients and was 69.33 in V617F mutation positive MPD patients, the latter was obviously higher than former and than that in healthy Han individuals. In conclusion, a multiplex PCR method has been developed that is simple and useful to identify V617F mutation in JAK2 gene and its relationship to the 46/1 haplotype. In more than half of Chinese V617F-positive MPD patients, the V617F mutation locates in 46/1 haplotype in JAK2. The frequencies of 46/1 haplotype are statistically insignificant among Han, Tibetan and Yugu nationality populations.


Assuntos
Haplótipos , Janus Quinase 2/genética , Transtornos Mieloproliferativos/genética , Povo Asiático/genética , Etnicidade/genética , Feminino , Humanos , Masculino , Mutação
15.
Appl Biochem Biotechnol ; 160(5): 1341-55, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19418260

RESUMO

In this study, we investigated structural changes in alpha-glucosidase during urea denaturation. Alpha-glucosidase was inactivated by urea in a dose-dependent manner. The inactivation was a first-order reaction with a monophase process. Urea inhibited alpha-glucosidase in a mixed-type reaction. We found that an increase in the hydrophobic surface of this enzyme induced by urea resulted in aggregation caused by unstable folding intermediates. We also simulated the docking between alpha-glucosidase and urea. The docking simulation suggested that several residues, namely THR9, TRP14, LYS15, THR287, ALA289, ASP338, SER339, and TRP340, interact with urea. Our study provides insights into the alpha-glucosidase unfolding pathway and 3D structure of alpha-glucosidase.


Assuntos
Biologia Computacional , Desnaturação Proteica/efeitos dos fármacos , Dobramento de Proteína/efeitos dos fármacos , Saccharomyces cerevisiae/enzimologia , Ureia/farmacologia , alfa-Glucosidases/química , alfa-Glucosidases/metabolismo , Naftalenossulfonato de Anilina/metabolismo , Ativação Enzimática/efeitos dos fármacos , Cinética , Simulação de Dinâmica Molecular , Estrutura Quaternária de Proteína , Soluções , Espectrometria de Fluorescência , Fatores de Tempo
16.
Protein J ; 28(9-10): 448-56, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19921411

RESUMO

Kinetic changes of alpha-glucosidase from Saccharomyces cerevisiae in guanidinium chloride (GdmCl) and SDS solutions were investigated. The results showed both denaturants can lead conformational changes and loss of enzymatic activities. However, the concentrations of denaturants causing loss of activities were much lower than that of conformational changes, which suggested that the conformation of active site of alpha-glucosidase was more fragile than the whole molecular conformation in response to the two denaturants. According to the different kinetic process of the enzyme in the GdmCl and SDS solutions, the further investigation on the process of denaturation were made, it showed GdmCl and SDS had different types of inhibition and different types of interaction with the enzyme. Furthermore, the mechanisms of the two denaturants were discussed.


Assuntos
Saccharomyces cerevisiae/enzimologia , alfa-Glucosidases/química , Guanidina/química , Cinética , Conformação Proteica , Desnaturação Proteica , Dobramento de Proteína , Dodecilsulfato de Sódio/química , Tensoativos/química
17.
Int J Biol Macromol ; 44(2): 149-55, 2009 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-19100283

RESUMO

Arginine kinase (AK; EC 2.7.3.3) is a key enzyme in the cellular energy metabolism of insects. Screening on potential effective inhibitors of AK may provide a pathway for novel, environmentally friendly insecticides. The results in this study indicated that rutin, as a noncompetitive inhibitor, interacts with AK mainly by a hydrophobic force forming an intermolecular complex with AK, which is according to the thermodynamic parameters obtained. Using a flexible docking method (AutoDock) the interaction between rutin and AK were further analyzed, which suggested in order to screen effective inhibitors, flexible active sites of AK (Ser63, Gly64, Val65, Tyr68) should be taken in account.


Assuntos
Arginina Quinase/antagonistas & inibidores , Simulação por Computador , Modelos Moleculares , Rutina/farmacologia , Animais , Sítios de Ligação , Gafanhotos/enzimologia , Concentração de Íons de Hidrogênio/efeitos dos fármacos , Cinética , Rutina/química , Espectrometria de Fluorescência , Temperatura , Termodinâmica
18.
Zhonghua Jie He He Hu Xi Za Zhi ; 26(4): 210-3, 2003 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-12901827

RESUMO

OBJECTIVE: To study the clinicopathological significance of heparanase and VEGF expression in NSCLC. METHODS: Eighty-five lung samples were studied. Each sample was divided into two parts, one used for heparanase mRNA detection by reverse transcription PCR and the other for VEGF detection by immunohistochemistry. RESULTS: (1) The expressions of heparanase mRNA and VEGF were higher in NSCLC than in benign pulmonary diseases (P < 0.05). (2) The expression of heparanase mRNA was higher in cases with lymph-node invasion, metastasis, stage III and IV diseases, low-differentiation, and adenocarcinoma, as compared to cases without lymph-node invasion and metastasis, with stage I and II diseases, higher and moderate differentiation, and squamous cell cancer (P < 0.05). Its expression was higher in tumors larger than 5 cm in size (P < 0.05). (3) The expression of VEGF was higher in cases with lymph-node invasion, metastasis, and stage III and IV disease, as compared to cases without lymph-node invasion and metastasis, and with stage I and II diseases (P < 0.05). (4) There was no significant correlation between heparanase and VEGF expression (P > 0.05). CONCLUSIONS: Heparanase and VEGF are associated with NSCLC invasion and metastasis, and may be used to evaluate NSCLC metastasis status. Heparanase and VEGF promote NSCLC invasion and metastasis by independent mechanisms. Detection of these two markers may improve the sensitivity and specificity of the measurement of NSCLC metastatic potential.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Fatores de Crescimento Endotelial/biossíntese , Glucuronidase/biossíntese , Neoplasias Pulmonares/metabolismo , Adulto , Idoso , Biomarcadores Tumorais/biossíntese , Carcinoma Pulmonar de Células não Pequenas/secundário , Feminino , Glucuronidase/genética , Humanos , Técnicas In Vitro , Neoplasias Pulmonares/patologia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , RNA Mensageiro/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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