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1.
Cell Commun Signal ; 20(1): 138, 2022 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-36076237

RESUMO

BACKGROUND: Gastrointestinal stromal tumours (GISTs) are the most common mesenchymal tumours of the gastrointestinal tract and are characterized by activating mutations of c-KIT or PDGFRa receptor tyrosine kinases (RTKs). Despite the clinical success of tyrosine kinase inhibitors (TKIs), more than half of GIST patients develop resistance due to a second mutation. Cyclin-dependent kinase 7 (CDK7) is the catalytic subunit of CDK-activating kinase (CAK), and it plays an important role in the regulation of cell cycle transitions and gene transcription. THZ1, a CDK7 inhibitor, exhibits a dose-dependent inhibitory effect in various cancers. METHODS: Data from the public GEO database and tissue microarray were used to analyse the gene expression levels of CDKs in GISTs. The impact of CDK7 knockdown and the CDK7 inhibitor THZ1 on GIST progression was investigated in vitro using CCK-8, colony formation, and flow cytometry assays and in vivo using a xenograft mouse model. RNA sequencing was performed to investigate the mechanism of GIST cell viability impairment mediated by THZ1 treatment. RESULTS: Our study demonstrated that CDK7 is relatively overexpressed in high-risk GISTs and predicts a poor outcome. A low concentration of THZ1 exhibited a pronounced antineoplastic effect in GIST cells in vivo and in vitro. Moreover, THZ1 exerted synergistic anticancer effects with imatinib. THZ1 treatment resulted in transcriptional modulation by inhibiting the phosphorylation of Ser2, Ser5, and Ser7 within RNA polymerase II (RNAPII). c-KIT, an oncogene driver of GIST, was transcriptionally repressed by THZ1 treatment or CDK7 knockdown. Transcriptome sequencing analysis showed that OSR1 acts as a downstream target of CDK7 and regulates c-KIT expression. Taken together, our results highlight elevated CDK7 expression as a predictor of poor outcome in GIST and present the combination of CDK7 and RTK inhibitors as a potent therapeutic strategy to improve the efficacy of GIST treatment. Video abstract.


Assuntos
Antineoplásicos , Tumores do Estroma Gastrointestinal , Fenilenodiaminas/farmacologia , Pirimidinas/farmacologia , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Quinases Ciclina-Dependentes/genética , Quinases Ciclina-Dependentes/metabolismo , Tumores do Estroma Gastrointestinal/tratamento farmacológico , Tumores do Estroma Gastrointestinal/genética , Tumores do Estroma Gastrointestinal/metabolismo , Humanos , Camundongos , Fosforilação , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas c-kit/genética , Proteínas Proto-Oncogênicas c-kit/metabolismo , Quinase Ativadora de Quinase Dependente de Ciclina
2.
Scand J Gastroenterol ; 53(10-11): 1328-1334, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30346846

RESUMO

AIM: The majority of available data on the clinical efficacy of sunitinib in patients with imatinib-resistant or -intolerant gastrointestinal stromal tumours (GISTs) are from studies of western populations. We investigated the clinical outcomes of imatinib dose escalation versus sunitinib in first-line imatinib-failure Asian GIST patients to further guide clinical treatment. METHODS: Patients received imatinib dose escalation and a shift to sunitinib (Group A) or a direct shift to sunitinib (Group B). The objective tumour response was assessed according to Choi's criteria. Progression-free survival (PFS) and overall survival (OS) were calculated. The relationship between genetic mutation and survival was analysed. RESULTS: In total, 40 patients who fulfilled the inclusion criteria were recruited. The differences in survival between Group A and Group B were not significant for PFS (p = .776) or OS (p = .219). For patients with KIT exon 11 mutation, a trend towards a better PFS was found in Group B (p = .122), OS of Group B was better than Group A (p = .013). The median PFS and OS of sunitinib treatment were 8 and 24 months, respectively, and a clinical benefit was observed in 80%. Patients with KIT exon 11 mutations had better PFS compared to those with KIT exon 9 mutations or wild-type GISTs (p = .017, p = .040, respectively). CONCLUSIONS: Both imatinib dose escalation and sunitinib were optional in Asian patients after failure of first-line imatinib, and patients with KIT exon 11 mutation benefited more from a direct shift to sunitinib.


Assuntos
Neoplasias Gastrointestinais/tratamento farmacológico , Neoplasias Gastrointestinais/genética , Tumores do Estroma Gastrointestinal/tratamento farmacológico , Tumores do Estroma Gastrointestinal/genética , Mesilato de Imatinib/administração & dosagem , Proteínas Proto-Oncogênicas c-kit/genética , Sunitinibe/administração & dosagem , Adulto , Idoso , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , China , Intervalo Livre de Doença , Resistencia a Medicamentos Antineoplásicos/genética , Éxons , Feminino , Neoplasias Gastrointestinais/mortalidade , Tumores do Estroma Gastrointestinal/mortalidade , Humanos , Mesilato de Imatinib/efeitos adversos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Mutação , Intervalo Livre de Progressão , Sunitinibe/efeitos adversos
3.
J Surg Res ; 209: 37-44, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28032569

RESUMO

BACKGROUND: The prognostic nutritional index (PNI) is a useful parameter indicating the immune and nutritional status of cancer patients; this study investigated the prognostic value of the PNI in advanced gastric cancer patients treated with preoperative chemotherapy. MATERIALS AND METHODS: We retrospectively reviewed 117 advanced gastric cancer patients who met the inclusion criteria for preoperative chemotherapy and underwent surgical resection from July 2004 to December 2011. The patients were divided into PNI-high (PNI ≥ 45) and PNI-low (PNI < 45) groups. Clinicopathologic features, chemotherapy adverse events, and surgical complications were compared between the prechemotherapy PNI-high and PNI-low groups using the chi-square test. Survival analysis was performed using the Kaplan-Meier method and log-rank test. The Cox proportional hazard model was used to identify prognostic factors. RESULTS: Overall survival was better in the prechemotherapy PNI-high group than in the PNI-low group (hazard ratio [HR] = 2.237, 95% confidence interval [CI]: 1.271-3.393, P = 0.005), while there was no significant difference in Overall survival between the postchemotherapy PNI-high and PNI-low groups (P > 0.05). Cox regression analysis indicated that yield pathologic T (ypT), yield pathologic N (ypN) stage, and prechemotherapy PNI were independent prognostic factors (ypT: HR = 2.914, 95% CI = 1.312-6.470, P = 0.009; ypN: HR = 4.909, 95% CI = 1.764-13.660, P = 0.003; prechemotherapy PNI: HR = 1.963, 95% CI = 1.101-3.499, P = 0.022). CONCLUSIONS: The prechemotherapy PNI is a useful predictor of the long-term outcome of patients with advanced gastric cancer treated with preoperative chemotherapy.


Assuntos
Estado Nutricional , Neoplasias Gástricas/mortalidade , Adulto , Idoso , Antineoplásicos/efeitos adversos , China/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Complicações Pós-Operatórias/epidemiologia , Prognóstico , Estudos Retrospectivos , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/cirurgia
4.
Cancer Sci ; 105(2): 150-8, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24261990

RESUMO

Regulatory T cells (Tregs) and plasmacytoid dendritic cells (pDCs) play important roles in the immune escape of cancer. In this study, we investigated pDCs and pDC-induced inducible costimulator (ICOS)(+) Treg populations in peripheral blood from gastric cancer (GC) patients and healthy donors by flow cytometry. The distribution of these cells in carcinoma tissue, peritumor tissue, and normal gastric mucosa was detected by immunohistochemistry. Plasma and tissue concentration of the cytokines such as interleukin-10 and transforming growth factor-ß1 were also measured. We found that the numbers of pDCs, Tregs, and ICOS(+) Tregs in peripheral blood were increased in GC patients compared with healthy donors. In tissue, Tregs and ICOS(+) Tregs were found distributing mainly in carcinoma tissue, whereas pDCs were mainly found in peritumor tissue. Moreover, the Foxp3(+) ICOS(+) /Foxp3(+) cell ratio in carcinoma and peritumor tissue were higher than that in normal tissue. There were more ICOS(+) Tregs in tumor and peritumor tissue of late-stage GC patients. There was a positive correlation between pDCs and ICOS(+) Tregs in peripheral blood and peritumor tissue from GC patients. In conclusion, pDCs may play a potential role in recruiting ICOS(+) Tregs, and both participate in the immunosuppression microenvironment of GC.


Assuntos
Células Dendríticas/imunologia , Proteína Coestimuladora de Linfócitos T Induzíveis/imunologia , Neoplasias Gástricas/imunologia , Linfócitos T Reguladores/imunologia , Microambiente Tumoral/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Feminino , Humanos , Tolerância Imunológica/imunologia , Interferon-alfa/imunologia , Interleucina-10/imunologia , Masculino , Pessoa de Meia-Idade , Neoplasias Gástricas/patologia
5.
J Sci Food Agric ; 92(4): 943-51, 2012 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-22002592

RESUMO

BACKGROUND: Cottonseed meal, an important source of feed raw materials, has limited use in the feed industry because of the presence of the highly toxic gossypol. The aim of the current work was to isolate the gossypol-degrading fungus from a soil microcosm and investigate the proteins involved in gossypol degradation. RESULTS: A fungal strain, AN-1, that uses gossypol as its sole carbon source was isolated and identified as Aspergillus niger. A large number of intracellular proteins were detected using sodium dodecyl sulfate-polyacrylamide gel electrophoresis, but no significant difference was observed between the glucose-containing and gossypol-containing mycelium extracts. Two-dimensional gel electrophoresis results showed that the protein spots were concentrated in the 25.0-66.2 kDa range and distributed in different pI gradients. PDQuest software showed that 51 protein spots in the gels were differentially expressed. Of these, 20 differential protein spots, including six special spots expressed in gossypol, were analyzed using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. CONCLUSION: The fungus AN-1 biodegraded gossypol and the proteomic analysis results indicate that some proteins were involved in the gossypol biodegradation during fungus survival, using gossypol as its sole carbon source.


Assuntos
Aspergillus niger/metabolismo , Gossipol/metabolismo , Proteômica/métodos , Sequência de Aminoácidos , Aspergillus niger/classificação , Aspergillus niger/isolamento & purificação , Aspergillus niger/ultraestrutura , Sequência de Bases , China , Eletroforese em Gel Bidimensional , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Gossypium/química , Gossipol/toxicidade , Dados de Sequência Molecular , Tipagem Molecular , Micélio/classificação , Micélio/isolamento & purificação , Micélio/metabolismo , Micélio/ultraestrutura , Técnicas de Tipagem Micológica , Mapeamento de Peptídeos , Filogenia , RNA Ribossômico 18S/química , RNA Ribossômico 18S/genética , Sementes/efeitos adversos , Sementes/química , Homologia de Sequência , Microbiologia do Solo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
6.
World J Microbiol Biotechnol ; 28(3): 929-35, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22805813

RESUMO

A modified error-prone PCR and high-throughout screening system based on 96-well plate were employed to improve catalytic activity of a hybrid xylanase (ATx). The mutant (FSI-A124) with enhanced activity was further heterologously expressed in Pichia pastoris under the control of GAP promoter. The recombinant xylanase driven by the Saccharomyces cerevisiae α-mating factor was secreted into culture medium. After growth in YPD medium for 96 h, xylanase activity in the culture supernatant reached 66.1 U ml(-1), which was 2.92 times as that of its parent. 6 × His-tagged purification increased the specific activity to 1557.61 U mg(-1). The optimum temperature and pH of recombinant xylanase were 55°C and 6.0, respectively. A single amino acid substitution (L49P) was observed within sequence of the mutant. Insight of the three dimensional structure revealed that proline possibly produced weaker hydrogen bond, van der Waals force and hydrophobic interaction with other residues nearby than leucine, especially for V174, contributing to the flexibility of catalytic residue E177. In this study, FSI-A124 exhibited higher xylanase activity but poorer thermostability than its parent, indicating that activity and stability might be negatively correlated.


Assuntos
Substituição de Aminoácidos , Mutagênese Sítio-Dirigida , Xilosidases/genética , Xilosidases/metabolismo , Domínio Catalítico , Meios de Cultura/química , Expressão Gênica , Concentração de Íons de Hidrogênio , Pichia/enzimologia , Pichia/genética , Reação em Cadeia da Polimerase/métodos , Regiões Promotoras Genéticas , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Saccharomyces cerevisiae/genética , Temperatura , Xilosidases/isolamento & purificação
7.
Front Immunol ; 13: 905057, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36389669

RESUMO

The effect of immunotherapy strategy has been affirmed in the treatment of various tumors. Nevertheless, the latent role of RNA 5-methylcytosine (m5C) modification in gastric cancer (GC) tumor microenvironment (TME) cell infiltration is still unclear. We systematically explore the m5C modification patterns of 2,122 GC patients from GEO and TCGA databases by 16 m5C regulators and related these patterns to TME characteristics. LASSO Cox regression was employed to construct the m5Cscore based on the expression of regulators and DEGs, which was used to evaluate the prognosis. All the GC patients were divided into three m5C modification clusters with distinct gene expression characteristics and TME patterns. GSVA, ssGSEA, and TME cell infiltration analysis showed that m5C clusters A, B, and C were classified as immune-desert, immune-inflamed, and immune-excluded phenotype, respectively. The m5Cscore system based on the expression of eight genes could effectively predict the prognosis of individual GC patients, with AUC 0.766. Patients with a lower m5Cscore were characterized by the activation of immunity and experienced significantly longer PFS and OS. Our study demonstrated the non-negligible role of m5C modification in the development of TME complexity and inhomogeneity. Assessing the m5C modification pattern for individual GC patients will help recognize the infiltration characterization and guide more effective immunotherapy treatment.


Assuntos
Neoplasias Gástricas , Microambiente Tumoral , Humanos , Microambiente Tumoral/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/terapia , RNA , Prognóstico , Imunoterapia
8.
Am J Reprod Immunol ; 88(5): e13615, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36029201

RESUMO

OBJECTIVE: We aimed to evaluate the efficacy of IVIG in the treatment with patients with recurrent spontaneous abortion (RSA). METHODS: PubMed, Embase, Web of science, Cochrane library were searched for randomized controlled (RCTs) about effect of IVIG on RSA from inception to August 20, 2021. Values of standardized mean differences (SMD) were determined for continuous outcomes. RESULTS: A total of 15 articles involving 902 patients were included in meta-analysis. Compared with the control group, IVIG can increase the live birth rate of recurrent spontaneous abortion patients [OR = 3.06, 95%CI (1.23, 7.64, P = .02]. However, recurrent abortion was divided into primary and secondary abortion for subgroup analysis, and there was no statistical difference. Besides, IVIG can also increase the expression in peripheral blood CD3+[OR = .4, 95%CI(-2.47, 3.15, P = .81],CD4+[OR = 1.16, 95%CI(-4.60, 6.93, P = .69], and a decrease in the expression of CD8+[OR = -1.78, 95%CI(-5.30, 1.75, P = .32], but there is no statistical significance. CONCLUSIONS: IVIG can significantly increase the live birth rate of recurrent spontaneous abortion. However, the evidence needs further verification and the curative effect is uncertain. It is necessary to further explore the pathogenesis of recurrent abortion and the mechanism of IVIG in the treatment of recurrent spontaneous abortion. Besides, more high-quality randomized controlled trials suitable for population, race, dosage and timing of IVIG in the treatment of recurrent abortion are needed to confirm its effectiveness, and effective systematic evaluation is also needed to evaluate its use benefit.


Assuntos
Aborto Habitual , Aborto Espontâneo , Gravidez , Feminino , Humanos , Imunoglobulinas Intravenosas , Aborto Habitual/terapia , Coeficiente de Natalidade
9.
Front Oncol ; 12: 903487, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35847933

RESUMO

Background: The clinical benefit of hepatectomy in patients with liver metastases from gastrointestinal stromal tumors (GIST) has not been well defined in this era of tyrosine kinase inhibitor (TKI). Our study aims to demonstrate the survival advantage of adding hepatectomy in patients with GIST liver metastases. Methods: Information on patients with metastatic GIST treated or consulted between January 2006 and December 2018 was retrieved. Patients without extrahepatic metastases were included and classified into the surgical (S group) and non-surgical (NS group). Clinicopathological features were compared and their association with survival was assessed. Results: A total of 119 patients were included in this retrospective analysis, 62 in the S group and 59 in the NS group. Comparison of clinicopathological features showed that a markedly higher proportion of patients in the S group had ≤3 hepatic lesions (79.0% vs. 29.8%, p<0.001). After a median follow-up duration of 56 months, patients in the S group had significantly better progression-free survival (PFS) and marginally improved overall survival (OS) than those in the NS group (3y PFS:86.2% vs. 64.6%, p=0.002; 5y OS: 91.5% vs. 78.3%, p=0.083). After propensity score matching, multivariate analysis identified hepatectomy as the only significant prognostic factor for PFS while age, hepatectomy and max tumor diameter were significant predictor for OS. Conclusions: Addition of hepatectomy provided longer disease control in patients with metastatic GIST confined to the liver. Upfront hepatectomy followed by imatinib therapy is worthwhile trying in patients with single and easily removable lesions.

10.
J Gastrointest Surg ; 25(8): 2091-2100, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33169322

RESUMO

PURPOSE: To characterize the immune cell profile and expression of PD-1, PD-L1, and IDO in PDGFRA-mutant gastrointestinal stromal tumors (GISTs). METHODS: The clinicopathological data of PDGFRA-mutant GIST patients who received surgical resection in Zhongshan Hospital between January 2013 and August 2019 were reviewed retrospectively. The specimens of tissue chips were detected for immune cell infiltration and the expression of PD-1, PD-L1, and IDO by immunohistochemical staining. RESULTS: CD3+, CD8+, and CD68+ cells were the main infiltrating immune cells in the 42 patients included in this study. In addition, CD4+, CD56+, Foxp3+, and CD20+ cells were also observed. A higher CD8+ T cell count was associated with smaller tumor size and PDGFRA D842V mutation (P = 0.047, P = 0.005). A higher CD3+ and CD68+ cell count was associated with a higher mitotic index (P = 0.022, P = 0.006). CD4+ and CD20+ cell count was associated with tumor morphology (P = 0.002, P = 0.045). PD-1 expression was present in 37 (88%) samples. Eighteen samples were positive for PD-L1 expression, and it was higher in small vs. large tumors (P = 0.012) and epithelioid and mixed cell type vs. spindle cell type GISTs (P = 0.046). IDO expression was positive in all 42 patients. The number of CD4+ cells was significantly greater in the specimens with high IDO expression (P = 0.012). CONCLUSION: There were abundant infiltrating immune cells in PDGFRA-mutant GISTs. PD-L1 expression was negatively associated with tumor size. The immunotherapy targeting PD-1/PD-L1 checkpoint and IDO may be valuable.


Assuntos
Antígeno B7-H1 , Tumores do Estroma Gastrointestinal , Linfócitos do Interstício Tumoral , Receptor de Morte Celular Programada 1 , Antígeno B7-H1/genética , Tumores do Estroma Gastrointestinal/genética , Tumores do Estroma Gastrointestinal/imunologia , Humanos , Receptor de Morte Celular Programada 1/genética , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética , Estudos Retrospectivos , Microambiente Tumoral
11.
Front Oncol ; 11: 789915, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34956906

RESUMO

PURPOSE: Immunotherapy for gastrointestinal stromal tumors (GISTs) remains a clinical challenge. The present study aimed to explore the clinical and prognostic significance of immune cell infiltration and PD-L1 expression in GISTs. METHODS: A total of 507 clinical tissue specimens of primary GISTs were collected for immunohistochemical analysis of immune cell infiltration and PD-L1 expression. Influencing factors of survival were evaluated by Kaplan-Meier analysis. Univariate and multivariate analyses were performed using the Cox regression model. RESULTS: There were significant differences in sex, tumor location, size, mitotic index, NIH risk grade, and cell morphology between different gene mutation types of GISTs. Immune cell infiltration in GISTs mainly involved macrophages and T cells. PD-1 was expressed in 48.5% of the tissue specimens, and PD-L1 expression was detected in 46.0% of the samples. PD-L1 expression was negatively correlated with the tumor size and mitotic index but positively correlated with the number of CD8+ T cells. There were significant differences in the number of CD8+ T cells between different gene mutation types. Wild type-mutant GISTs were enriched with CD8+ T cells as compared with KIT- and PDGFRA-mutant GISTs. The number of CD8+ T cells was higher in non-gastric GISTs. PD-L1 and CD8+ T cells were independent predictors for better relapse-free survival of GISTs. CONCLUSIONS: PD-L1 expression is a predictive biomarker for better prognosis of GISTs. Non-gastric GIST patients with wild-type mutations may be the beneficiaries of PD-1/PD-L1 inhibitors.

12.
J Cancer ; 10(12): 2679-2686, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31258776

RESUMO

Background: The prognostic nutritional index (PNI) is a useful parameter that indicates the immunonutritional status of patients with malignant tumors. In this retrospective study, we aimed to investigate the value of PNI to predict the outcome of gastrointestinal stromal tumors (GISTs). Material and methods: This study enrolled 431 GIST patients who underwent curative resection from January 2000 to December 2012. A receiver operating characteristic (ROC) curve analysis was used to identify the cutoff value of PNI, neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR). Survival curves were produced using the Kaplan-Meier method and were compared using a log-rank test. The Cox proportional hazards model was used to identify independent prognostic factors. Results: Of the 431 patients, 209 (48.5%) were male and 222 (51.5%) were female. The median age was 56 (range 20-80 years old). The PNI cutoff value was 47.45, with a sensitivity of 61.1 % and a specificity of 69.9 %. Compared to the PNI-low group (PNI < 47.45), the PNI-high group (PNI ≥47.45) had a significantly longer recurrence-free survival (RFS) (5-year RFS rate 89.9% versus 70.8%, p<0.001). Patients with higher PNI (p<0.001), lower NLR (p<0.001) and lower PLR (p=0.002) had significant better prognosis. PNI was found to be an independent prognostic factor of RFS (hazard ratio [HR] =1.967, 95% confidence interval [95% CI]: 1.243-3.114, p=0.004). Conclusions: PNI is a simple and useful marker that can predict the prognosis of GIST.

13.
Protein Pept Lett ; 15(1): 39-42, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18221011

RESUMO

Beta-propeller phytases (BPPs) are a special class of enzyme that are mainly isolated from Bacillus and are widely used in animal nutrition, human health and environmental protection. BPPs class exhibits both unique Ca2+-dependent catalytic property and highly strict substrate specificity for the calcium-phytate complex. This review describes the effect of Ca2+ on the catalytic activity, thermal stability, and structural conformation of BPPs.


Assuntos
6-Fitase/química , 6-Fitase/metabolismo , Cálcio/metabolismo , Ácido Fítico/metabolismo , Animais , Bacillus/enzimologia , Sítios de Ligação , Ativação Enzimática , Estabilidade Enzimática , Humanos , Hidrólise , Conformação Proteica
14.
Biol Trace Elem Res ; 124(2): 144-56, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18425433

RESUMO

Zinc deficiency induces a striking reduction of food intake in animals. To elucidate the mechanisms for this effect, two studies were connectedly conducted to determine the effects of peripheral administration of zinc on food intake in rats fed the zinc-adequate or zinc-deficient diets for a 3-week period. In study 1, two groups of male Sprague-Dawley rats were provided diets made either adequate (ZA; 38.89 mg/kg) or deficient (ZD; 3.30 mg/kg) in zinc. In study 2, after feeding for 3 weeks, both ZA and ZD groups received intraperitoneal (IP) injection of zinc solution with three levels (0.5, 1.0, and 2.0 microg zinc/g body weight, respectively) and cumulative food intake at 0.5, 1, 2, 4, and 24 h, and plasma hormones concentrations were measured. The results in study 1 showed rats fed the ZD diets revealed symptoms of zinc deficiency, such as sparse and coarse hair, poor appetite, susceptibility to surroundings, lethargy, and small movements. Zinc concentrations in serum, femur, and skeletal muscle of rats fed the ZD diets declined by 26.58% (P < 0.01), 27.32% (P < 0.01), and 24.22% (P < 0.05), respectively, as compared with ZA control group. These findings demonstrated that rat models with zinc deficiency and zinc adequacy had been fully established. The results in study 2 showed that IP administration of zinc in both ZA and ZD rats did not influence food intake at each time points (P > 0.05), although zinc deficiency suppressed food intake. Plasma neuropeptide Y (NPY) was higher, but insulin and glucagon were lower in response to zinc deficiency or zinc administration by contrast with their respective controls (P < 0.05). Leptin, T3, and T4 concentrations were uniformly decreased (P < 0.05) in rats fed the ZD diets in contrast to ZA diets; however, no differences (P > 0.05) were observed during zinc injection. Calcitonin gene-related peptide was unaffected (P > 0.05) by either zinc deficiency or zinc administration. The present studies suggested that zinc administration did not affect short-term food intake in rats even in the zinc-deficient ones; the reduced food intake induced by zinc deficiency was probably associated with the depression in thyroid hormones. The results also indicated that NPY and insulin varied conversely during the control of food intake.


Assuntos
Suplementos Nutricionais , Ingestão de Alimentos/efeitos dos fármacos , Zinco/deficiência , Zinco/farmacologia , Animais , Peptídeo Relacionado com Gene de Calcitonina/sangue , Deficiências Nutricionais/sangue , Deficiências Nutricionais/dietoterapia , Glucagon/sangue , Insulina/sangue , Leptina/sangue , Masculino , Neuropeptídeo Y/sangue , Ratos , Ratos Sprague-Dawley , Tiroxina/sangue , Tri-Iodotironina/sangue
15.
Physiol Plant ; 131(4): 614-21, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18251852

RESUMO

The mechanisms of photoprotection of photosynthesis and dissipation of excitation energy in rice leaves in response to potassium (K) deficiency were investigated. Net photosynthetic rate and the activity of ribulose-1,5-bisphosphate carboxylase/oxygenase decreased under K deficiency. Compared with the control, non-photochemical quenching of Chl fluorescence increased in K-deficient plant, whereas the efficiency of excitation transfer (F'(v)/F'(m)) and the photochemical quenching coefficient (q(P)) decreased. Thus, thermal dissipation of excitation energy increased as more excess electrons were accumulated in the photosynthetic chain. The electron transport rate through PSII (J(f)) was more sensitive to O2 concentration, and the fraction of electron transport rate required to sustain CO2 assimilation and photorespiration (J(g)/J(f)) was significantly decreased under K deficiency compared with the control. Furthermore, the alternative electron transport (J(a)/J(f)) was increased, indicating that a considerable amount of electrons had been transported to O2 during the water-water cycle in the K-deficient leaves. Although the fraction of electron transport to photorespiration (J(o)/J(f)) was also increased in the K-deficient leaves, it was less sensitive than that of the water-water cycle. With the generation of reactive oxygen species level, the activities of superoxide dismutase and ascorbate peroxidase, two of the key enzymes involved in scavenging of active oxygen species in the water-water cycle, also increased in K-deficient rice. Therefore, it is likely that a series of photoprotective mechanisms were initiated in rice plants in response to K deficiency and the water-water cycle might be critical for protecting photosynthetic apparatus under K deficiency in rice.


Assuntos
Oryza/fisiologia , Fotossíntese/fisiologia , Folhas de Planta/fisiologia , Potássio/farmacologia , Água/metabolismo , Clorofila/metabolismo , Transporte de Elétrons , Cinética , Oryza/efeitos dos fármacos , Oryza/crescimento & desenvolvimento , Fotossíntese/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Deficiência de Potássio , Ribulose-Bifosfato Carboxilase/metabolismo , Superóxidos/metabolismo
16.
Ann Nutr Metab ; 51(4): 345-51, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17726312

RESUMO

BACKGROUND: This study evaluated effects of zinc on the hepatic lipid peroxidation, antioxidant components and mRNA expression levels in rats. METHODS: Three diets with different Zn levels including Zn adequacy (ZA; 34.50 mg/kg, control), Zn deficiency (ZD; 3.30 mg/kg), and Zn overdose (ZO; 345.45 mg/kg) were fed to rats for 6 weeks. The mRNA expression levels were analyzed by cDNA microarrays. RESULTS: The body weight of rats fed the ZD diet was less (p < 0.01) than that of rats fed the ZA diet. Zn overdose elevated body weight, but the increase was not detected (p > 0.05) at week 6. Although copper and iron status in serum were declined (p < 0.01), those in liver were not affected (p > 0.05) by the high intake of zinc. The glutathione peroxidase (GPx) and glutathione (GSH) remained unchanged (p > 0.05) by zinc treatment. Rats fed the ZD diet showed reductions(p < 0.01) in the Cu-Zn superoxide dismutase (Cu-Zn SOD) and catalase (CAT) activity, and increases (p < 0.01) in the malondialdehyde and hydrogen peroxide (H(2)O(2)) contents. Rats fed the ZO diet particularly had higher Cu-Zn SOD (p < 0.01) activity. The mRNA expression levels of SOD were upregulated in the ZO group, and CAT was downregulated in the ZD group, while no changes in GPx mRNA levels were found after zinc treatment. CONCLUSION: The study suggested that zinc deficiency largely decreased body weight; zinc overdose, however, moderately stimulated growth in the early growing phase of rats. High dietary zinc did not compete with liver copper and iron status. Although Zn deficiency impaired antioxidant functions, zinc overdose hardly enhanced the antioxidant systems of animals.


Assuntos
Regulação da Expressão Gênica , Fígado/metabolismo , RNA Mensageiro/metabolismo , Zinco/deficiência , Zinco/farmacologia , Animais , Antioxidantes/metabolismo , Peso Corporal/efeitos dos fármacos , Cobre/metabolismo , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica/efeitos dos fármacos , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Peróxido de Hidrogênio/metabolismo , Ferro/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/enzimologia , Masculino , Malondialdeído/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Oxirredução , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo
17.
Biol Trace Elem Res ; 115(2): 187-94, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17435261

RESUMO

Zinc (Zn) is an essential trace element required for human beings and animals. This divalent cation is involved in many physiological functions, including immune and antioxidant function, growth, and reproduction. Deficiency of Zn produces several pathological disorders and abnormalities in its metabolism, such as anorexia, weight loss, poor efficiency, and growth retardation. Although it has been known for more than 50 yr that Zn deficiency regularly and consistently causes anorexia in many animal species, the mechanism that causes this phenomenon still remains an enigma. The present review describes recent research investigating the relationship between Zn deficiency and the regulation of food intake, as well as macronutrient selection.


Assuntos
Ingestão de Alimentos , Fenômenos Fisiológicos da Nutrição , Zinco/metabolismo , Animais , Humanos , Zinco/deficiência
18.
Onco Targets Ther ; 10: 2655-2664, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28579803

RESUMO

AIM: The role of neutrophil-lymphocyte ratio (NLR) and derived neutrophil-lymphocyte ratio (d-NLR) in outcome prediction is assessed in patients with advanced gastric cancer receiving preoperative chemotherapy in a 5-year follow-up cohort. PATIENTS AND METHODS: Patients undergoing preoperative chemotherapy and sequential R0 resection for advanced gastric cancer were enrolled from July 2004 to November 2011. Wilcoxon matched-pairs signed-rank test was used to evaluate the change of peripheral blood parameters. Receiver operating curve was used to identify the optimal cutoff values of NLR and d-NLR. Survival function was analyzed using Kaplan-Meier curves and Cox proportional hazard model. RESULTS: Significant difference was found between baseline and post-chemotherapy blood parameters, including leukocytes, neutrophils, lymphocytes, NLR and d-NLR (all P<0.05). High baseline NLR group (NLR ≥2.230) had a significant shorter recurrence-free survival (RFS) (hazard ratio [HR] =1.814, 95% confidence interval [95% CI]: 1.112-2.960, P=0.015) and shorter overall survival (OS) (HR =1.867, 95% CI: 1.129-3.089, P=0.013) than those of the low baseline NLR group (NLR <2.230). High baseline d-NLR group (d-NLR ≥1.885) also had a shorter RFS (HR =1.805, 95% CI: 1.116-2.919, P=0.014) and shorter OS (HR =1.783, 95% CI: 1.091-2.916, P=0.019) than those of the low baseline d-NLR group (d-NLR <1.885). However, post-chemotherapy NLR and d-NLR showed no prognostic significance on RFS and OS (all P>0.05). Multivariate analysis showed that higher baseline NLR but not d-NLR was identified as an independent factor associated with worse RFS (HR =1.707, 95% CI: 1.042-2.797, P=0.034) and worse OS (HR =1.758, 95% CI: 1.058-2.919, P=0.029). CONCLUSION: Baseline NLR and d-NLR may serve as convenient, easily measured prognostic indicators in advanced gastric cancer treated with preoperative chemotherapy and sequential R0 resection, especially to baseline NLR, which showed independent prognostic significance on RFS and OS, while post-chemotherapy NLR and d-NLR lost their usefulness due to the inhibition of bone marrow hematopoietic function. Patients with high baseline NLR and d-NLR values need multimodal therapy.

19.
Nutrition ; 22(2): 187-96, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16413754

RESUMO

OBJECTIVE: The present study simultaneously investigated the effects of different zinc (Zn) levels on the growth performance and relative biochemical parameters in growing rats and analyzed the molecular mechanism of zinc influencing food intake. METHODS: Three diets with different Zn levels--Zn adequate (ZA; 35.94 mg/kg, control), Zn deficient (ZD; 3.15 mg/kg), and Zn overdose (ZO; 347.50 mg/kg)--were fed to rats for 6 wk. Dietary Zn was supplemented with ZnSO4. The relation between zinc and food intake was studied by pituitary cDNA microarrays. RESULTS: Compared with ZA group, rats fed the ZD diet showed decreases in body weight (P < 0.01), food intake (P < 0.05), tissue zinc concentrations (P < 0.01), and specific activities of alkaline phosphatase (P < 0.01) and copper/Zn superoxide dismutase (P < 0.05), whereas the ZO diet had positive effects on body weight (P < 0.05), zinc concentrations (P < 0.01), and alkaline phosphatase activity (P < 0.05). The villi of the jejunum became shorter (P < 0.01), shriveled, and flattened. This change in morphology decreased absorption surface area, and there was a substantial decrease (P < 0.01) in villi number per unit area in ZD rats. Metallothionein concentration was increased in livers of rats fed ZD (P < 0.01) and ZO (P < 0.05) diets. Moreover, ZD and ZO influenced normal growth and development of organs. The results from pituitary cDNA arrays indicated that different Zn levels affect gene expression of appetite-related peptides, including neuropeptide-Y, melanin-concentrating hormone, ghrelin, calcitonin gene-related product, and serotonin. CONCLUSION: The present results showed that zinc deficiency has a negative effect on the growth performance and biochemical parameters of rats. The ZO diet increased body weight (P < 0.05) but had no effect (P > 0.05) on food intake, copper/Zn superoxide dismutase activity, and intestinal morphology. The ZD diet decreased rat food intake by regulating appetite-related gene expression in the pituitary gland.


Assuntos
Peso Corporal/efeitos dos fármacos , Ingestão de Alimentos/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Hipófise/metabolismo , Ratos/crescimento & desenvolvimento , Zinco/farmacologia , Fosfatase Alcalina/metabolismo , Animais , Relação Dose-Resposta a Droga , Absorção Intestinal/efeitos dos fármacos , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Tamanho do Órgão/efeitos dos fármacos , Hipófise/efeitos dos fármacos , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo , Zinco/deficiência , Zinco/metabolismo
20.
J Zhejiang Univ Sci B ; 7(9): 690-5, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16909468

RESUMO

The objective of this work was to investigate the effect of six individual strains of fungi on the reduction of gossypol levels and nutritional value during solid substrate fermentation of cottonseed meal (CSM). Six groups of disinfected CSM substrate were incubated for 48 h after inoculation with either of the fungi C. capsuligena ZD-1, C. tropicalis ZD-3, S. cerevisae ZD-5, A. terricola ZD-6, A. oryzae ZD-7, or A. niger ZD-8. One not inoculated group (substrate) was used as a control. Levels of initial and final free gossypol (FG), crude protein (CP), amino acids (AA) and in vitro digestibility were assayed. The experiment was done in triplicate. The experimental results indicated that microbial fermentation could greatly decrease (P<0.05) FG levels in CSM. The detoxification efficiency differed between the species of microorganisms applied. From the perspective of reducing CSM potential toxicity, C. tropicalis ZD-3 was most successful followed by S. cerevisae ZD-5 and A. niger ZD8. They could reduce FG levels of CSM to 29.8, 63.07 and 81.50 mg/kg based on DM (dry matter), respectively, and their detoxification rate were 94.57%, 88.51% and 85.16%, respectively. If crude protein, amino acids content and their in vitro digestibility were also taken into account, A. niger ZD-8 may be the best choice. The CP content of CSM substrate fermented by C. tropicalis ZD-3 and A. niger ZD-8 were improved by 10.76% and 22.24%; the TAA (total amino acids) contents were increased by 7.06% and 11.46%, and the EAA (essential amino acids) were raised by 7.77% and 12.64%, respectively. Especially, the levels of methionine, lysine and threonine were improved greatly (P<0.05). The in vitro CP digestibility of CSM fermented by C. tropicalis ZD-3 and A. niger ZD-8 was improved by 13.42% and 18.22%, the TAA were increased by 17.75% and 22.88%, and the EAA by 16.61% and 21.01%, respectively. In addition, the in vitro digestibility of methionine, lysine and threonine was also improved greatly (P<0.05).


Assuntos
Óleo de Sementes de Algodão/metabolismo , Fermentação , Fungos/metabolismo , Gossipol/análise , Aminoácidos/análise , Óleo de Sementes de Algodão/química , Digestão , Valor Nutritivo , Proteínas de Plantas/análise
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