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1.
World J Clin Cases ; 12(11): 1900-1908, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38660542

RESUMO

The coexistence of venous thromboembolism (VTE) within patients with cancer, known as cancer-associated thrombosis (CAT), stands as a prominent cause of mortality in this population. Over recent years, the incidence of VTE has demonstrated a steady increase across diverse tumor types, influenced by several factors such as patient management, tumor-specific risks, and treatment-related aspects. Furthermore, mutations in specific genes have been identified as potential contributors to increased CAT occurrence in particular cancer subtypes. We conducted an extensive review encompassing pivotal historical and ongoing studies on CAT. This review elucidates the risks, mechanisms, reliable markers, and risk assessment methodologies that can significantly guide effective interventions in clinical practice.

2.
J Dent Sci ; 18(4): 1567-1575, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37799898

RESUMO

Background/purpose: Epigallocatechin-3-gallate (EGCG) is playing an increasingly important role in the treatment of oral diseases. However, its mechanisms remain to be clarified. This study aimed to investigate the effect of EGCG on oxidative and inflammatory stress and bone loss in experimental periodontitis. Materials and methods: Periodontitis was induced in rats, followed by gavage using different concentrations of EGCG for 5 weeks. The levels of interleukin-1ß (IL-1ß), interleukin-18 (IL-18), tumor necrosis factor-α (TNF-α), superoxide dismutase (SOD) and malondialdehyde (MDA) in rats were measured. The degree of alveolar bone loss and the number of inflammatory cells were detected. The integrated optical density of nuclear factor erythroid 2-related factor (Nrf2), heme oxygenase-1 (HO-1), NLR pyrin domain-containing 3 (NLRP3) and nuclear factor-kappaB p65 (NF-κB p65) was measured. Results: EGCG (200 mg/kg) significantly reduced alveolar bone loss in the ligated maxillary molars and the number of inflammatory cells in the EGCG-200 group compared with the periodontitis, EGCG-100 and EGCG-400 groups. 200 mg/kg was the optimal dose of EGCG and was used in subsequent experiments. The expression levels of IL-1ß, IL-18, TNF-α and MDA were significantly lower and the expression level of SOD was significantly higher in the EGCG-200 group compared with the periodontitis group. The expression of NLRP3 and NF-κB p65 was significantly decreased, while the expression of Nrf2 and HO-1 was significantly increased in the EGCG-200 group compared with the periodontitis group. Conclusion: These results suggest that EGCG inhibits oxidative stress and inflammatory responses in the periodontitis model by modulating the Nrf2/HO-1/NLRP3/NF-κB p65 signaling pathway, thereby decreasing alveolar bone loss.

3.
Front Surg ; 9: 926141, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35910468

RESUMO

Background: Cholecystitis with incarcerated gallstones (CIG) is a type of acute abdomen in the field of hepatobiliary surgery. Whether gallbladder-preserving surgery (GPS) can be performed to treat it, however, depends on the improvement of gallbladder contractile function. The present study aimed to investigate the changes in gallbladder contractile function and its influencing factors after minimally invasive GPS for CIG. Methods: A total of 95 patients with CIG treated in the Aerospace Center Hospital between May 2017 and May 2019 were enrolled as the study subjects. All patients received minimally invasive GPS. The patients' operation-related conditions (including stone removal success rate, duration of surgery, intraoperative blood loss, etc.), changes in gallbladder contractile function, and influencing factors of GPS were analyzed. Results: Among the 95 patients included in the study, the success rate of stone removal was 100%, the duration of surgery was 76.0 ± 26.5 min, and the intraoperative blood loss was 10.17 ± 4.43 ml. The rate of good gallbladder contractile function at one and two years after surgery was significantly higher than before surgery (P < 0.05). Age, duration of surgery, stone recurrence, and diabetes were the independent risk factors for postoperative gallbladder contractile function (P < 0.05). Conclusion: Minimally invasive GPS for patients with CIG has a good curative effect. The changes in gallbladder contractile function after the surgery are influenced by many factors.

4.
Int J Mol Sci ; 23(14)2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35887161

RESUMO

O-linked ß-N-acetylglucosamine (O-GlcNAc) modification is a ubiquitous, reversible, and highly dynamic post-translational modification, which takes charge of almost all biological processes examined. However, little information is available regarding the molecular regulation of O-GlcNAcylation in granulosa cell function and glucose metabolism. This study focused on the impact of disrupted O-GlcNAc cycling on the proliferation and apoptosis of bovine granulosa cells, and further aimed to determine how this influenced glucose metabolism. Pharmacological inhibition of OGT with benzyl-2-acetamido-2-deoxy-α-D-galactopyranoside (BADGP) led to decreased cellular O-GlcNAc levels, as well as OGT and OGA protein expressions, whereas increasing O-GlcNAc levels with the OGA inhibitor, O-(2-acetamido-2-deoxy-D-gluco-pyranosylidene) (PUGNAc), resulted in elevated OGA protein expression and decreased OGT protein expression in granulosa cells. Dysregulated O-GlcNAc cycling reduced cell viability, downregulated the proliferation-related genes of CDC42 and PCNA transcripts, upregulated the pro-apoptotic genes of BAX and CASPASE-3 mRNA and the ratio of BAX/BCL-2, and increased the apoptotic rate. Glycolytic enzyme activities of hexokinase and pyruvate kinase, metabolite contents of pyruvate and lactate, mitochondrial membrane potential, ATP levels, and intermediate metabolic enzyme activities of succinate dehydrogenase and malate dehydrogenase involved in the tricarboxylic acid cycle, were significantly impaired in response to altered O-GlcNAc levels. Moreover, inhibition of OGT significantly increased the expression level of thioredoxin-interacting protein (TXNIP), but repression of OGA had no effect. Collectively, our results suggest that perturbation of O-GlcNAc cycling has a profound effect on granulosa cell function and glucose metabolism.


Assuntos
Acetilglucosamina , N-Acetilglucosaminiltransferases , Acetilglucosamina/metabolismo , Animais , Bovinos , Feminino , Glucose/metabolismo , Células da Granulosa/metabolismo , Homeostase , N-Acetilglucosaminiltransferases/metabolismo , Processamento de Proteína Pós-Traducional , Proteína X Associada a bcl-2/metabolismo , beta-N-Acetil-Hexosaminidases/metabolismo
5.
Gels ; 8(6)2022 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-35735715

RESUMO

The gel plugging and flooding system has a long history of being researched and applied, but the Changqing reservoir geological characteristics are complex, and the synergistic performance of the composite gel foam plugging system is not fully understood, resulting in poor field application. Additionally, the technique boundary chart of the heterogeneous reservoir plugging system has hardly appeared. In this work, reservoir models of porous, fracture, and pore-fracture were constructed, a composite gel foam plugging system was developed, and its static injection and dynamic profile control and oil displacement performance were evaluated. Finally, combined with the experimental studies, a technical boundary chart of plugging systems for heterogeneous reservoirs is proposed. The research results show that the adsorption effect of microspheres (WQ-100) on the surface of elastic gel particles-1 (PEG-1) is more potent than that of pre-crosslinked particle gel (PPG) and the deposition is mainly on the surface of PPG. The adsorption effect of PEG-1 on the surface of PPG is not apparent, primarily manifested as deposition stacking. The gel was synthesized with 0.2% hydrolyzed polyacrylamide (HPAM) + 0.2% organic chromium cross-linking agent, and the strength of enhanced gel with WQ-100 was higher than that of PEG-1 and PPG. The comprehensive value of WQ-100 reinforced foam is greater than that of PEG-1, and PPG reinforced foam, and the enhanced foam with gel has a thick liquid film and poor foaming effect. For the heterogeneous porous reservoir with the permeability of 5/100 mD, the enhanced foam with WQ-100 shows better performance in plugging control and flooding, and the recovery factor increases by 28.05%. The improved foam with gel enhances the fluid flow diversion ability and the recovery factor of fractured reservoirs with fracture widths of 50 µm and 180 µm increases by 29.41% and 24.39%, respectively. For pore-fractured reservoirs with a permeability of 52/167 mD, the PEG + WQ-100 microsphere and enhanced foam with WQ-100 systems show better plugging and recovering performance, and the recovery factor increases are 20.52% and 17.08%, 24.44%, and 21.43%, respectively. The smaller the particle size of the prefabricated gel, the more uniform the adsorption on the foam liquid film and the stronger the stability of the foam system. The plugging performance of the composite gel system is stronger than that of the enhanced gel with foam, but the oil displacement performance of the gel-enhanced foam is better than that of the composite gel system due to the "plug-flooding-integrated" feature of the foam. Combined with the plugging and flooding performance of each plugging system, a technique boundary chart for the plugging system was established for the coexisting porous, fracture, and pore-fracture heterogeneous reservoirs in Changqing Oilfield.

6.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 38(6): 638-643, 2022 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-37308409

RESUMO

Objective: To study the effects of estradiol (E2) on alleviating myocardial ischemia/reperfusion(I/R) injury through estrogen receptorß(ERß) mediated extracellular regulated protein kinases(ERK) pathway activation. Methods: Eighty-four adult female SD rats were ovariectomized and randomly divided into control group, NC siRNA adeno-associated virus (AAV) group received sham operation, the myocardial I/R injury model was prepared by ligation of the left anterior descending coronary artery in I/R group, E2+I/R group, NC siRNA AAV+I/R group, NC siRNA AAV+E2+I/R group and ERß-siRNA AAV+E2+I/R group. E2+I/R group, NC siRNA AAV+E2+I/R group and ERß-siRNA AAV+E2+I/R group were treated with E2 0.8 mg/kg by gavage for 60 days before modeling. NC siRNA AAV+I/R group, NC siRNA AAV+E2+I/R group, and ERß-siRNA AAV+E2+I/R group were treated with AAV by caudal vein injection 24 h before modeling. After 120 min of reperfusion, the contents of serum lactate dehydrogenase (LDH), phosphocreatine kinase (CK), phosphocreatine kinase isoenzyme (CK-MB), myocardial infarction area and the expressions of ERß, p-ERK, the contents of tumor necrosis factor-α(TNF-α), interleukin-1ß(IL-1 ß), malondialdehyde (MDA) and total antioxidant capacity (T-AOC) in myocardium were measured. Results: The contents of serum LDH, CK, CK-MB, myocardial infarction area and the contents of TNF-α, IL-1 ß, MDA in myocardium of I/R group were higher than those of the control group, the expression levels of ERß and p-ERK and the content of T-AOC were lower than those in the control group (P<0.05). The contents of serum LDH, CK and CK-MB, myocardial infarction area and the contents of TNF-α, IL-1 ß and MDA in myocardium of E2+I/R group were lower than those of the I/R group, the expression levels of ERß and p-ERK and the content of T-AOC were higher than those of the I/R group(P<0.05). After knockdown ERß by caudal vein injection of ERß-siRNA AAV, the contents of serum LDH, CK and CK-MB, myocardial infarction area and the contents of TNF-α, IL-1 ß and MDA in myocardium of ERß-siRNA AAV+E2+I/R group were higher than those of NC-siRNA AAV+E2+I/R, the expression levels of ERß and p-ERK and the content of T-AOC were lower than those of NC-siRNA AAV+E2+I/R(P<0.05). Conclusion: E2 has protective effects on myocardial I / R injury in ovariectomized rats, which are related to the promotion of ERß mediating the activation of ERK pathway, reducing inflammatory and oxidative stress responses.


Assuntos
Infarto do Miocárdio , Isquemia Miocárdica , Traumatismo por Reperfusão Miocárdica , Feminino , Animais , Ratos , Ratos Sprague-Dawley , Estradiol , Interleucina-1beta , Receptor beta de Estrogênio , Fosfocreatina , Fator de Necrose Tumoral alfa , RNA Interferente Pequeno , Creatina Quinase , Creatina Quinase Forma MB , Antioxidantes
7.
Bioresour Bioprocess ; 9(1): 17, 2022 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38647808

RESUMO

Endo-ß-mannanases are important enzymes for degrading lignocellulosic biomass to generate mannan, which has significant health effects as a prebiotic that promotes the development of gut microbiota. Here, a novel endo-ß-mannanase belonging to glycoside hydrolase (GH) family 113 from Paenibacillus cineris (PcMan113) was cloned, expressed and characterized, as one of only a few reported GH113 family ß-mannanases. Compared to other functionally and structurally characterized GH113 mannanases, recombinant PcMan113 showed a broader substrate spectrum and a better performance. Based on a structural homology model, the highly active mutant PcMT3 (F110E/N246Y) was obtained, with 4.60- and 5.53-fold increases of enzyme activity (towards KG) and catalytic efficiency (kcat/Km, against M5) compared with the WT enzyme, respectively. Furthermore, molecular dynamics (MD) simulations were conducted to precisely explore the differences of catalytic activity between WT and PcMT3, which revealed that PcMT3 has a less flexible conformation, as well as an enlarged substrate-binding channel with decreased steric hindrance and increased binding energy in substrate recognition. In conclusion, we obtained a highly active variant of PcMan113 with potential for commercial application in the manufacture of manno-oligosaccharides.

8.
Front Pharmacol ; 12: 771487, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34955843

RESUMO

Vincristine (VCR) is the first-line chemotherapeutic medication often co-administered with other drugs to treat childhood acute lymphoblastic leukemia. Dose-dependent neurotoxicity is the main factor restricting VCR's clinical application. VCR-induced peripheral neuropathy (VIPN) sometimes results in dose reduction or omission, leading to clinical complications or affecting the patient's quality of life. With regard to the genetic basis of drug responses, preemptive pharmacogenomic testing and simultaneous blood level monitoring could be helpful for the transformation of various findings into individualized therapies. In this review, we discussed the potential associations between genetic variants in genes contributing to the pharmacokinetics/pharmacodynamics of VCR and VIPN incidence and severity in patients with acute lymphoblastic leukemia. Of note, genetic variants in the CEP72 gene have great potential to be translated into clinical practice. Such a genetic biomarker may help clinicians diagnose VIPN earlier. Besides, genetic variants in other genes, such as CYP3A5, ABCB1, ABCC1, ABCC2, TTPA, ACTG1, CAPG, SYNE2, SLC5A7, COCH, and MRPL47, have been reported to be associated with the VIPN, but more evidence is needed to validate the findings in the future. In fact, a variety of complex factors jointly determine the VIPN. In implementing precision medicine, the combination of genetic, environmental, and personal variables, along with therapeutic drug monitoring, will allow for a better understanding of the mechanisms of VIPN, improving the effectiveness of VCR treatment, reducing adverse reactions, and improving patients' quality of life.

9.
Enzyme Microb Technol ; 150: 109891, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34489044

RESUMO

ß-Mannanases hydrolyze lignocellulosic biomass with the release of mannan oligosaccharides, which are considered as renewable resource in higher plants. Here, we cloned, expressed and characterized a novel endo-ß-mannanase (ManAC) from Aspergillus calidoustus. Homology alignment analysis indicated that ManAC belonged to glycosyl hydrolase (GH) 5 family members. The analysis of structural homologous model revealed that five residues, Arg116, Asn231, His305, Tyr307, and Trp370, constituted the active site of ManAC. Glu232 and Glu340, proton donor and nucleophile, formed the catalytic residues of ManAC. The recombinant ManAC exhibited maximal activity at pH 2.5 and 70 °C, and it was acid tolerant at a pH range of 2.0-6.0 and thermostable under 60 °C. Meanwhile, the activity of ManAC was not significantly affected by various metal ions, except for Mg2+ and Ag2+. The recombinant ManAC exhibited the highest ß-mannanase activity towards locust bean gum (669.7 U/mg) with the Km and Vmax values of 3.4 mg/mL and 982.4 µmol/min/mg, respectively. These thermophilic and acidophilicc characteristics is better than most extreme ß-mannanase. As the first reported mannanse from Aspergillus calidoustus (ManAC), these excellent properties of ManAC strongly promote the synthesis of mannooligosaccharides which have potential for food and feed industrial applications.


Assuntos
Aspergillus , beta-Manosidase , Aspergillus/genética , Clonagem Molecular , Oligossacarídeos , beta-Manosidase/genética
10.
Appl Microbiol Biotechnol ; 105(20): 7801-7811, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34581846

RESUMO

Quorum sensing is a mechanism that facilitates cell-to-cell communication. Through signal molecular density for signal recognition, which leads to the regulation of some physiological and biochemical functions. Gluconacetobacter xylinus CGMCC 2955, which produces bacterial cellulose (BC), synthesizes the LuxR protein belonging to the LuxI/LuxR type QS system. Here, a luxR overexpression vector was transformed into G. xylinus CGMCC 2955. The overexpression of luxR increased the yield of BC by 15.6% after 16 days static culture and reduced the cell density by 15.5% after 120-h-agitated culture. The glucose was used up by G. xylinus-pMV24-luxR at 72-h-agitated fermentation, which 12 h earlier than the wild-type (WT). The total N-acylhomoserine lactones (AHL) content of the luxR-overexpressing strain and the WT strain attained 1367.9 ± 57.86 mg/L and 842.9 ± 54.22 mg/L, respectively. The C12-HSL and C14-HSL contents of G. xylinus-pMV24-luxR were 202 ± 21.66 mg/L and 409.6 ± 0.91 mg/L, which were significantly lower than that of WT. In contrast, C6-HSL showed opposite results. The difference of AHL content proved that overexpression of luxR improved the binding of AHL and showed preference for some specific AHL. The metabolic results demonstrated that upon glucose exhaustion, the consumption of gluconic acid was promoted by luxR overexpression, and the content of D- ( +)-trehalose, an antiretrograde metabolite, increased significantly. KEY POINTS: • The overexpression of luxR increased the yield of bacterial cellulose • The content of signal molecules was significantly different • Differential metabolites were involved in multiple metabolic pathways.


Assuntos
Gluconacetobacter xylinus , Percepção de Quorum , Acil-Butirolactonas , Proteínas de Bactérias/genética , Celulose , Gluconacetobacter xylinus/genética , Transativadores/genética
11.
Am J Chin Med ; 49(5): 1017-1044, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34107860

RESUMO

The ongoing coronavirus disease 2019 (COVID-19) pandemic calls for effective control and prevention. Chinese medicine (CM) has developed systematic theories and approaches for infectious disease prevention over 2000 years. Here, we review and analyze Chinese herbal medicines (CHM) used in infectious disease prevention from ancient pestilences to modern epidemics and pandemics to share cumulative preventive medical experience. A total of 829 formulas, including 329 herbs from 189 ancient books, 131 formulas with 152 herbs, and 13 Chinese patent medicines (CPM) from 30 official Chinese prevention programs used in ancient epidemics, SARS, influenza and COVID-19 prevention, were reviewed and analyzed. Preventive CHM mainly has four functions and can be taken orally or applied externally. CHM that kill pathogens (Realgar [Xionghuang], Cyrtomium Fortunei J. Sm[Guanzhong]) were commonly used externally for disinfection in ancient prevention while CHM tonifying Qi (Astragali Radix [Huangq], Glycyrrhizae Radix et Rhizoma [Gancao]) are used for modern prevention. Taking CHM that expel pathogens (Realgar [Xionghuang], Lonicerae Japonicae Flos[Jinyinhua]) and CHM eliminating dampness (Atractylodis Rhizoma [Cangzhu], Pogostemonis Herba[Guanghuoxiang]) have been commonly used from ancient times to COVID-19. Damp toxins are a common characteristic of infectious diseases such as SARS and COVID-19. Thus, taking CHM expelling damp toxins and tonifying Qi are the main methods for SARS and COVID-19 prevention. CHM with different approaches have been widely used in infectious disease prevention from ancient times to the present. Multiple CM prevention methods may provide new perspectives for future pandemics.


Assuntos
COVID-19/prevenção & controle , Medicamentos de Ervas Chinesas/administração & dosagem , Animais , COVID-19/epidemiologia , Composição de Medicamentos , Medicamentos de Ervas Chinesas/química , Humanos , Medicina Tradicional Chinesa , Pandemias
12.
Sci Rep ; 10(1): 3544, 2020 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-32103037

RESUMO

Bacillus licheniformis BL1 was used as a starting strain to construct the recombinant tetramethylpyrazine (TMP)-producing strains by over-expression of the α-acetolactate decarboxylase gene (aldC) and α-acetolactate synthase gene (alsS), named BLC, BLS and BLCS, respectively. Then the addition of acetaldehyde was use to enhance the TMP yield in the fermentation process. During microaerobic fermentation, the aldC-overexpressed BLC strain produced 43.75 g TMP/L which was 15.47% higher than the TMP in culture yielded using the initial BL1 strain. Furthermore, the acetoin yield as TMP precursor similarly rose by 23.06% in BLC recombinant strain. In contrast, the 2,3-BD increased by 23.2% in the recombinant BLCS. TMP produced by BL1 could be bolstered via the supplementation of the acetaldehyde in fermentation medium. This method also has the same effect on the BLC strain.


Assuntos
Acetaldeído/metabolismo , Bacillus licheniformis/genética , Bacillus licheniformis/metabolismo , Carboxiliases/genética , Regulação Bacteriana da Expressão Gênica , Pirazinas/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Fermentação , Engenharia Metabólica , Plasmídeos/genética
13.
Transl Cancer Res ; 9(8): 4476-4487, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35117813

RESUMO

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is a type of exocrine pancreatic cancer that presents itself in the form of a highly malignant tumor. However, in the past few decades, with breakthroughs in the diagnosis and treatment of malignant tumors, there have yet to be satisfactory results for the diagnosis (early diagnosis) and treatment of PDAC. Therefore, the biological behavior of PDAC still requires more research to be understood. CYP24A1 is currently considered to be an essential part of vitamin D (VD) metabolism and increasingly reported to be associated with malignant tumors. Therefore, this study aims to explore the relationship between CYP24A1 and the clinicopathological features and prognosis of PDAC. METHODS: Seventy-three surgical PDAC cases were collected and follow-ups were made. The expression of CYP24A1 was obtained by the immunohistochemistry and the tissue FAXS cytometry (TFC) system. The related quantitative indices included the percentage of positive cells (%) and the average staining intensity of the positive cells (in) in the cancer zone (C) and the adjacent non-cancer zone (ANC). The relationship between CYP24A1 and the clinicopathological parameters, as well as the prognosis of PDAC was then analyzed. Furthermore, Fluorescence quantitative PCR, Western-blot, siRNA, and phenotypic testing were implemented in the Pan-C1 PDAC cells. RESULTS: In normal pancreatic tissue, CYP24A1 was approximately "zero-expressed" in the exocrine glands. In the C and ANC zones, the expression of CYP24A1 increased significantly. In cases with a higher C%, the proportion of lymph node metastasis was lower (P=0.071); In cases with a higher ANC% (P=0.026) and higher ANCin (P=0.079), the proportion of high differentiation was higher; in survival analysis, C%, Cin had a significant effect on survival and those with higher parameters had a lower risk of death. In the cell experiments, after CYP24A1 was silenced, the migration ability of PDAC cells did not change significantly and its proliferation (P=0.034) and invasion (P=0.002) ability decreased significantly. CONCLUSIONS: CYP24A1 has a significant effect on the development and prognosis of PDAC.

14.
Math Biosci Eng ; 17(1): 179-201, 2019 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-31731346

RESUMO

In this paper, a mathematical model for microbial treatment in livestock and poultry sewage is proposed and analyzed. We consider periodic addition of microbial flocculants to treat microorganisms such as Escherichia coli in sewage. Different from the traditional models, a class of composite dynamics models composed of impulsive differential equations is established. Our aim is to study the relationship between substrate, microorganisms and flocculants in sewage systems as well as the treatment strategies of microorganisms. Precisely, we first show the process of mathematical modeling by using impulsive differential equations. Then by using the theory of impulsive differential equations, the dynamics of the model is investigated. Our results show that the system has a microorganismsextinction periodic solution which is globally asymptotically stable when a certain threshold value is less than one, and the system is permanent when a certain threshold value is greater than one. Furthermore, the control strategy for microorganisms treatment is discussed. Finally, some numerical simulations are carried out to illustrate the theoretical results.


Assuntos
Esgotos/microbiologia , Águas Residuárias/microbiologia , Purificação da Água/métodos , Animais , Simulação por Computador , Escherichia coli , Floculação , Gado , Modelos Biológicos , Oscilometria , Dinâmica Populacional , Aves Domésticas
15.
J Int Med Res ; 43(3): 279-89, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25956156

RESUMO

OBJECTIVE: To compare the growth of preterm infants fed standard protein-fortified human milk with that containing human milk fortifier (HMF) with a higher-than-standard protein content. METHODS: Published articles reporting randomized controlled trials and prospective observational intervention studies listed on the PubMed®, Embase®, CINAHL and Cochrane Library databases were searched using the keywords 'fortifier', 'human milk', 'breastfeeding', 'breast milk' and 'human milk fortifier'. The mean difference with 95% confidence intervals was used to compare the effect of HMF with a higher-than-standard protein content on infant growth characteristics. RESULTS: Five studies with 352 infants with birth weight ≤ 1750 g and a gestational age ≤ 34 weeks who were fed human milk were included in this meta-analysis. Infants in the experimental groups given human milk with higher-than-standard protein fortifier achieved significantly greater weight and length at the end of the study, and greater weight gain, length gain, and head circumference gain, compared with control groups fed human milk with the standard HMF. CONCLUSIONS: HMF with a higher-than-standard protein content can improve preterm infant growth compared with standard HMF.


Assuntos
Proteínas Alimentares , Suplementos Nutricionais , Alimentos Fortificados , Recém-Nascido Prematuro/crescimento & desenvolvimento , Leite Humano , Extração de Leite , Feminino , Humanos , Recém-Nascido , Aumento de Peso
16.
Zhong Yao Cai ; 38(7): 1454-9, 2015 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-26946843

RESUMO

OBJECTIVE: To observe the protective effects of Lycium barbarum polysaccharide(LBP) on focal cerebral ischemic reperfusion injury in mice, and to explore its mechanism. METHODS: Male mice were randomly divided into six groups: sham-operated group, middle cerebral artery occlusion(MCAO) mice group, MCAO mice treating with 4 mg/kg Nimodipine group and MCAO mice treating with 10, 20 and 40 mg/kg LBP groups. The mice were preventively administrated with LBP by intragastric administration for seven days. After 2 h of cerebral ischemia and 24 h of reperfusion, neurological scores in each group mice were estimated. Morphological changes in ischemic brain neurons were performed for HE staining. The number of apoptotic neurons was detected by Tunel staining. The Caspase-3 protein activity was measured by spectrophotometry. BAX and BCL-2 protein expressions in ischemic brains were investigated by Western blot analysis. RESULTS: Compared to the vehicle group, neurological deficit scores were significantly reduced in LBP pretreatment group(P <0.01). LBP( 10,20 and 40 mg/kg) groups relieved neuronal morphological damage respectively and also obviously attenuated the neuronal apoptosis (P <0. 05). Caspase-3 protein activity and BAX protein expression were obviously decreased(P <0. 05, P <0. 01) and BCL-2 protein expression was markedly increased(P <0. 01) in LBP pretreatment groups. CONCLUSION: LBP can protect against focal cerebral ischemic reperfusion injury in mice,the mechanism may be related with attenuating the apoptosis in ischemic brains.


Assuntos
Apoptose/efeitos dos fármacos , Isquemia Encefálica/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Animais , Caspase 3/metabolismo , Infarto da Artéria Cerebral Média , Masculino , Camundongos , Neurônios/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Traumatismo por Reperfusão/prevenção & controle , Proteína X Associada a bcl-2/metabolismo
17.
Pharm Biol ; 52(8): 1052-9, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24601951

RESUMO

CONTEXT: Oxysophocarpine (OSC), a quinolizidine alkaloid extracted from leguminous plants of the genus Robinia, is traditionally used for various diseases including neuronal disorders. OBJECTIVE: This study investigated the protective effects of OSC on neonatal rat primary-cultured hippocampal neurons were injured by oxygen-glucose deprivation and reperfusion (OGD/RP). MATERIALS AND METHODS: Cultured hippocampal neurons were exposed to OGD for 2 h followed by a 24 h RP. OSC (1, 2, and 5 µmol/L) and nimodipine (Nim) (12 µmol/L) were added to the culture after OGD but before RP. The cultures of the control group were not exposed to OGD/RP. MTT and LDH assay were used to evaluate the protective effects of OSC. The concentration of intracellular-free calcium [Ca(2+)]i and mitochondrial membrane potential (MMP) were determined to evaluate the degree of neuronal damage. Morphologic changes of neurons following OGD/RP were observed with a microscope. The expression of caspase-3 and caspase-12 mRNA was examined by real-time quantitative PCR. RESULTS: The IC50 of OSC was found to be 100 µmol/L. Treatment with OSC (1, 2, and 5 µmol/L) attenuated neuronal damage (p < 0.001), with evidence of increased cell viability (p < 0.001) and decreased cell morphologic impairment. Furthermore, OSC increased MMP (p < 0.001), but it inhibited [Ca(2+)]i (p < 0.001) elevation in a dose-dependent manner at OGD/RP. OSC (5 µmol/L) also decreased the expression of caspase-3 (p < 0.05) and caspase-12 (p < 0.05). DISCUSSION AND CONCLUSION: The results suggested that OSC has significant neuroprotective effects that can be attributed to inhibiting endoplasmic reticulum (ER) stress-induced apoptosis.


Assuntos
Alcaloides/farmacologia , Glucose/metabolismo , Hipocampo/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Oxigênio/metabolismo , Animais , Animais Recém-Nascidos , Hipóxia Celular/efeitos dos fármacos , Hipóxia Celular/fisiologia , Células Cultivadas , Hipocampo/citologia , Hipocampo/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão , Resultado do Tratamento
18.
Neurochem Res ; 38(11): 2408-17, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24078262

RESUMO

Our previous studies have demonstrated that oxysophoridine (OSR) has protective effects on cerebral neurons damage in vitro induced by oxygen and glucose deprivation. In this study, we further investigated whether OSR could reduce ischemic cerebral injury in vivo and its possible mechanism. Male Institute of cancer research mice were intraperitoneally injected with OSR (62.5, 125 and 250 mg/kg) for seven successive days, then subjected to brain ischemia induced by the model of middle cerebral artery occlusion. After reperfusion, neurological scores and infarct volume were estimated. Morphological examination of tissues was performed. Apoptotic neurons were detected by terminal deoxynucleotidyl transferase mediated dUTP nick end labeling staining. Oxidative stress levels were assessed by measurement of malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) levels. The expression of various apoptotic markers as Caspase-3, Bax and Bcl-2 were investigated by immunohistochemistry and Western-blot analysis. OSR pretreatment groups significantly reduced infract volume and neurological deficit scores. OSR decreased the percentage of apoptotic neurons, relieved neuronal morphological damage. Moreover, OSR markedly decreased MDA content, and increased SOD, GSH-Px activities. Administration of OSR (250 mg/kg) significantly suppressed overexpression of Caspase-3 and Bax, and increased Bcl-2 expression. These findings indicate that OSR has a protective effect on focal cerebral ischemic injury through antioxidant and anti-apoptotic mechanisms.


Assuntos
Alcaloides/farmacologia , Isquemia Encefálica/prevenção & controle , Traumatismo por Reperfusão/prevenção & controle , Animais , Apoptose/efeitos dos fármacos , Infarto da Artéria Cerebral Média/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Estresse Oxidativo/efeitos dos fármacos
19.
Basic Clin Pharmacol Toxicol ; 107(1): 560-4, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20148858

RESUMO

Upon binding agonist, the epidermal growth factor receptor (EGFR) is dimerized and auto-phosphorylated to activate downstream pathway that induces diverse physiology and pathology processes. Conventional methods for evaluation of EGFR inhibitors are limited. This study describes a duplexed on-microbead binding assay allowing competitive EGFR inhibitors to be quantificationally evaluated in vitro. Polystyrene microbeads barcoded by fluoresceine isothiocyanate fluorescence as high brightness and low brightness microspheres were coated with receptor tyrosine kinase (RTK) ligand-epidermal growth factor (EGF)/stem cell factor (SCF) and ATP/GTP, respectively. High and low brightness microbeads were mixed and incubated with EGFR and its competitive inhibitor in binding assay buffer. Phycoerythrin (PE) fluorescence-labelled antibody was employed to report the level of EGFR binding to EGF/SCF and ATP/GTP. Values were numbered via PE molecules assessed by quantitative flow cytometry. Results from this study demonstrated that incubation with EGFR identified by PE-labelled antibody can make EGF- and ATP-coated microbeads luminous. And EGF or ATP-competitive EGFR inhibitors, respectively, alleviated this in a concentration-dependent manner. Coating microbeads with SCF or GTP as a negative control cannot capture EGFR. The duplexed on-microbead binding assay in this study might be useful for discovering ligand- and ATP-competitive EGFR inhibitors in a rapid and quantificational approach.


Assuntos
Receptores ErbB/antagonistas & inibidores , Citometria de Fluxo/métodos , Ligação Proteica , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais Humanizados , Antineoplásicos/farmacologia , Cetuximab , Proposta de Concorrência , Fator de Crescimento Epidérmico/metabolismo , Receptores ErbB/análise , Receptores ErbB/metabolismo , Cloridrato de Erlotinib , Humanos , Microesferas , Inibidores de Proteínas Quinases/farmacologia , Quinazolinas/farmacologia
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