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1.
Small ; 20(15): e2307885, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38161253

RESUMO

For the development of acid-responsive advanced fluorescent films with a 2D nanostructure, a pyridyl cyanostilbene-based AIEgen (PCRM) is newly synthesized. The synthesized PCRM exhibits aggregation-induced emission (AIE) and responds reversibly to acid and base stimuli. To fabricate the nanoporous polymer-stabilized film, PCRM and 4-(octyloxy)benzoic acid (8OB) are complexed in a 1:1 ratio through hydrogen bonding. The PCRM-8OB complex with a smectic mesophase is uniaxially oriented at first and photopolymerized with a crosslinker. By subsequently removing 8OB in an alkaline solution, nanopores are generated in the self-assembled and polymerized hierarchical 2D nanostructure film. The prepared nanoporous fluorescent films exhibit not only the reversible response to acid and base stimuli but also mechanical and chemical robustness. Since the nanoporous fluorescent films have different sensitivities to trifluoroacetic acid (TFA) depending on the molecular orientation in the film, advanced acid vapor sensors that can display the risk level according to the concentration of TFA are demonstrated. Reactive AIEgens-based hierarchical nanostructure films with nanopores fabricated by a subsequent process of self-assembly, polymerization, and etching can open a new door for the development of advanced chemosensors.

2.
EMBO Rep ; 21(11): e49416, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-33030802

RESUMO

Prominin-1 (Prom1) is a major cell surface marker of cancer stem cells, but its physiological functions in the liver have not been elucidated. We analyzed the levels of mRNA transcripts in serum-starved primary WT (Prom1+/+ ) and KO (Prom1-/- ) mouse hepatocytes using RNA sequencing (RNA-seq) data, and found that CREB target genes were downregulated. This initial observation led us to determine that Prom1 deficiency inhibited cAMP response element-binding protein (CREB) activation and gluconeogenesis, but not cyclic AMP (cAMP) accumulation, in glucagon-, epinephrine-, or forskolin-treated liver tissues and primary hepatocytes, and mitigated glucagon-induced hyperglycemia. Because Prom1 interacted with radixin, Prom1 deficiency prevented radixin from localizing to the plasma membrane. Moreover, systemic adenoviral knockdown of radixin inhibited CREB activation and gluconeogenesis in glucagon-treated liver tissues and primary hepatocytes, and mitigated glucagon-elicited hyperglycemia. Based on these results, we conclude that Prom1 regulates hepatic PKA signaling via radixin functioning as an A kinase-anchored protein (AKAP).


Assuntos
Gluconeogênese , Glucose , Antígeno AC133/genética , Antígeno AC133/metabolismo , Animais , Proteínas do Citoesqueleto , Gluconeogênese/genética , Glucose/metabolismo , Hepatócitos , Fígado/metabolismo , Proteínas de Membrana , Camundongos
3.
Ecotoxicol Environ Saf ; 241: 113771, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35716406

RESUMO

Environmental sanitation of maternal contact during pregnancy is extremely important for the development of different fetal tissues and organs. In particular, during early pregnancy, any adverse exposure may cause abnormal fetal growth or inhibit the development of embryogenic organs. The potential risks of phthalate exposure, which affects the development of humans and animals, are becoming a serious concern worldwide. However, the specific molecular mechanism of di-(2-ethylhexyl) phthalate (DEHP)-induced cardiotoxicity in fetal mice remains unclear. In this study, animal models of DEHP gavage at concentrations of 250, 500, and 1000 mg/kg/day within 8.5-18.5 days of pregnancy were established. The cell proliferation, survival, and apoptosis rates were evaluated using CCK8, EdU, TUNEL and flow cytometry. The molecular mechanism was assessed via transcriptome sequencing, immunohistochemistry, immunofluorescence, reverse transcription-quantitative polymerase chain reaction, and Western blot analysis. In vivo, DEHP increased apoptosis, decreased Ki67 and CD31 expression, reduced heart weight and area, slowed down myocardial sarcomere development, and caused cardiac septal defect in fetal mice heart. Transcriptome sequencing showed that DEHP decreased NRG1 expression and downregulated the ErbB2/ErbB4-PI3K/AKT signaling pathway-related target genes. In vitro, primary cardiomyocytes were cultured with DEHP at a concentration of 150 µg/mL combined with ErbB inhibitor (AG1478, 10 µmol/L) and/or NRG1 protein (100 ng/mL) for 72 h. After DEHP intervention, the expression of NRG1 and the phosphorylation level of ErbB2, ErbB4, PI3K, and AKT decreased, and the apoptosis-related protein levels increased. Moreover, the apoptosis rate increased. After adding exogenous NRG1, the phosphorylation level of the NRG1/ERbB2/ERbB4-PI3K/AKT pathway increased, and the apoptosis-related protein levels decreased. Further, the apoptosis rate reduced. Interestingly, after exposure to DEHP and AG1478 + NRG1, the anti-apoptotic effect of NRG1 and cardiomyocyte proliferation decreased by inhibiting the NRG1/ERbB2/ERbB4-PI3K/AKT pathway. Hence, the NRG1-dependent regulation of the ERbB2/ERbB4-PI3K/AKT signaling pathway may be a key mechanism of DEHP-induced myocardial cytotoxicity.


Assuntos
Dietilexilftalato , Proteínas Proto-Oncogênicas c-akt , Animais , Dietilexilftalato/toxicidade , Feminino , Feto , Humanos , Camundongos , Neuregulina-1/farmacologia , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Ácidos Ftálicos , Gravidez , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor ErbB-2 , Receptor ErbB-4/genética , Receptor ErbB-4/metabolismo , Receptor ErbB-4/farmacologia , Transdução de Sinais
4.
Molecules ; 26(22)2021 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-34833952

RESUMO

Cardiac fibrosis is a heterogeneous disease, which is characterized by abundant proliferation of interstitial collagen, disordered arrangement, collagen network reconstruction, increased cardiac stiffness, and decreased systolic and diastolic functions, consequently developing into cardiac insufficiency. With several factors participating in and regulating the occurrence and development of cardiac fibrosis, a complex molecular mechanism underlies the disease. Moreover, cardiac fibrosis is closely related to hypertension, myocardial infarction, viral myocarditis, atherosclerosis, and diabetes, which can lead to serious complications such as heart failure, arrhythmia, and sudden cardiac death, thus seriously threatening human life and health. Resveratrol, with the chemical name 3,5,4'-trihydroxy-trans-stilbene, is a polyphenol abundantly present in grapes and red wine. It is known to prevent the occurrence and development of cardiovascular diseases. In addition, it may resist cardiac fibrosis through a variety of growth factors, cytokines, and several cell signaling pathways, thus exerting a protective effect on the heart.


Assuntos
Antifibróticos/uso terapêutico , Antioxidantes/uso terapêutico , Cardiopatias/tratamento farmacológico , Miocárdio/patologia , Resveratrol/uso terapêutico , Animais , Antifibróticos/farmacologia , Antioxidantes/farmacologia , Modelos Animais de Doenças , Coração/efeitos dos fármacos , Cardiopatias/patologia , Humanos , Resveratrol/farmacologia
5.
Opt Express ; 27(16): 23080-23094, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31510590

RESUMO

Rydberg blockaded gate is a fundamental ingredient for scalable quantum computation with neutral Rydberg atoms. However the fidelity of such a gate is intrinsically limited by a blockade error coming from a Rydberg level shift that forbids its extensive use. Based on a dark-state adiabatic passage, we develop a novel protocol for realizing a two-atom blockade-error-free quantum gate in a hybrid system with simultaneous van der Waals (vdWsI) and resonant dipole-dipole interactions (DDI). The basic idea relies on converting the roles of two interactions, which is, the DDI serves as one time-dependent tunable pulse and the vdWsI acts as a negligible middle level shift, as long as the adiabatic condition is preserved. We adopt an optimized super-Gaussian optical pulse with kπ(k ≫ 1) area accompanied by a smooth tuning for the DDI, composing a circular stimulated Raman adiabatic passage, which can robustly ensure a faster operation time ∼ 80ns as well as a highly-efficient gate fidelity ∼ 0.9996. This theoretical protocol offers a flexible treatment for hybrid interactions in complex Rydberg systems, enabling on-demand design of new types of effective Rydberg quantum gate devices.

6.
Wei Sheng Yan Jiu ; 46(3): 429-433, 2017 May.
Artigo em Zh | MEDLINE | ID: mdl-29903254

RESUMO

OBJECTIVE: To get a baseline of 32 provincial center for disease control and prevention( CDC) microbiology laboratory in the aspect of quantitative test ability of Staphylococcus aureu, qualitative test ability of diarrheagenic Escherichia coli and unknown intestinal pathogen, and to comprehend the quality of microbiology testing. METHODS: Two different concentration samples of Staphylococcus aureus I and II were made. Diarrheagenic Escherichia coli and unknown intestinal pathogen samples were transported using the special semi-solid AGAR transport medium, in the form of four pure different serotypes each. The results of Staphylococcus aureu were logarithmic transformed, and evaluated with Z-score method using the average and standard deviation. The reporting results of diarrheagenic Escherichia coli and unknown intestinal pathogen were evaluated as right or wrong, and non-reporting were evaluated as missing. RESULTS: The satisfaction rate of Staphylococcus aureus was 82. 81%. The accuracy rate of diarrheagenic Escherichia coli was 45. 16%. Of the 32 results of unknown intestinal pathogen, 29 CDCs reported correctSalmonella serotypes, and the accuracy rate was 90. 63%. Combined the three quality control results, 9 CDCs reached the accurate results, with the accuracy rate of 28. 13%. CONCLUSION: 32 provincial CDCs have the identification ability of Salmonella serotyping and qualitative test ability of Staphylococcus aureu, while they need to strength diarrheagenic Escherichia coli identification and serotyping ability.


Assuntos
Infecções por Escherichia coli/microbiologia , Escherichia coli/classificação , Escherichia coli/patogenicidade , Laboratórios/normas , Controle de Qualidade , China , Humanos , Sorotipagem
7.
Wei Sheng Yan Jiu ; 45(5): 766-776, 2016 Sep.
Artigo em Zh | MEDLINE | ID: mdl-29903129

RESUMO

OBJECTIVE: To survey the fungi contamination of four kinds of feed ingredients in 2013- 2014 from parts of China. METHODS: A total of 795 feed ingredients including soybean meal, cottonseed meal, wheat bran and distillers dried grains with soluble( DDGS) were collected from representative enterprises in different parts of China. Food safety national standards GB 4789. 15-2010 microbiological examination of food hygiene enumeration of molds and yeast and GB / T 4789. 16-2003 was used to enumerate, isolate and identify fungi, respectively. RESULTS: A total of 25 genus 54species kinds of fungi were isolated and the fungi from Aspergillus, Penicillium, Fusarium were the common contamination fungi in feed ingredients. Wheat bran was the most serious contaminated feed ingredients by fungi, and the detection rate of fungi contamination in four seasons were all greater than 84. 9%, and the exceeding feed limit rate was amount to 20. 8%. The fungi detection rate and contamination level were relatively lower in cottonseed meal and soybean meal, and the exceeding feed limit rate was 0. 9% and 1. 4%, respectively. There were types of feed ingredients, seasonal and regional differences for Aspergillus flavus and Fusarium moniliforme contamination. The detection rate of Aspergillus flavus in wheat bran was higher in four seasons and all surveyed areas, and autumn and winter and huazhong district were with the highest contamination level. The detection rate of Fusarium moniliforme for soybean meal in autumn and winter and huabei district was higher than others. The detection rate of Aspergillus flavus for DDGS was very low, but the detection rate of Fusarium moniliforme was higher, especially for autumn and huazhong district, the detection rate was 40. 4%and 50. 0%, respectively. CONCLUSION: The feed ingredients from China were commonly contaminated by fungi. It is recommended that strengthening the fungi contamination monitoring of feed ingredients from summer and autumn, huabei and huazhong district was an important prevention method.


Assuntos
Ração Animal , Contaminação de Alimentos/análise , Fungos , China , Microbiologia de Alimentos , Inquéritos e Questionários
8.
J Biol Chem ; 289(29): 20012-25, 2014 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-24895128

RESUMO

To address whether mitochondrial biogenesis is essential for skeletal myogenesis, C2C12 myogenesis was investigated after knockdown of NADH dehydrogenase (ubiquintone) flavoprotein 1 (NDUFV1), which is an oxidative phosphorylation complex I subunit that is the first subunit to accept electrons from NADH. The NDUFVI knockdown enhanced C2C12 myogenesis by decreasing the NAD(+)/NADH ratio and subsequently inactivating SIRT1 and SIRT1 activators (pyruvate, SRT1720, and resveratrol) abolished the NDUFV1 knockdown-induced myogenesis enhancement. However, the insulin-elicited activation of insulin receptor ß (IRß) and insulin receptor substrate-1 (IRS-1) was reduced with elevated levels of protein-tyrosine phosphatase 1B after NDUFV1 knockdown in C2C12 myotubes. The NDUFV1 knockdown-induced blockage of insulin signaling was released by protein-tyrosine phosphatase 1B knockdown in C2C12 myotubes, and we found that NDUFV1 or SIRT1 knockdown did not affect mitochondria biogenesis during C2C12 myogenesis. Based on these data, we can conclude that complex I dysfunction-induced SIRT1 inactivation leads to myogenesis enhancement but blocks insulin signaling without affecting mitochondria biogenesis.


Assuntos
Complexo I de Transporte de Elétrons/deficiência , Complexo I de Transporte de Elétrons/metabolismo , Insulina/metabolismo , Doenças Mitocondriais/metabolismo , Desenvolvimento Muscular/fisiologia , Músculo Esquelético/crescimento & desenvolvimento , Músculo Esquelético/metabolismo , Sirtuína 1/antagonistas & inibidores , Animais , Linhagem Celular , Complexo I de Transporte de Elétrons/antagonistas & inibidores , Complexo I de Transporte de Elétrons/genética , Técnicas de Silenciamento de Genes , Resistência à Insulina/fisiologia , Camundongos , Modelos Biológicos , Desenvolvimento Muscular/genética , Fibras Musculares Esqueléticas/metabolismo , NAD/metabolismo , Fosforilação Oxidativa , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo , RNA Interferente Pequeno/genética , Transdução de Sinais , Sirtuína 1/genética , Sirtuína 1/metabolismo
9.
Wei Sheng Yan Jiu ; 44(1): 73-6, 2015 Jan.
Artigo em Zh | MEDLINE | ID: mdl-25958641

RESUMO

OBJECTIVE: To test the aerobic plate count examining capability of microbiology laboratories, to ensure the accuracy and comparability of quantitative bacteria examination results, and to improve the quality of monitoring. METHODS: The 4 different concentration aerobic plate count piece samples were prepared and noted as I, II, III and IV. After homogeneity and stability tests, the samples were delivered to monitoring institutions. The results of I, II, III samples were logarithmic transformed, and evaluated with Z-score method using the robust average and standard deviation. The results of IV samples were evaluated as "satisfactory" when reported as < 10 CFU/piece or as "not satisfactory" otherwise. Pearson χ2 test was used to analyze the ratio results. RESULTS: 309 monitoring institutions, which was 99.04% of the total number, reported their results. 271 institutions reported a satisfactory result, and the satisfactory rate was 87.70%. There was no statistical difference in satisfactory rates of I, II and III samples which were 81.52%, 88.30% and 91.40% respectively. The satisfactory rate of IV samples was 93.33%. There was no statistical difference in satisfactory rates between provincial and municipal CDC. CONCLUSION: The quality control program has provided scientific data that the aerobic plate count capability of the laboratories meets the requirements of monitoring tasks.


Assuntos
Bactérias/isolamento & purificação , Técnicas de Laboratório Clínico/normas , Contagem de Colônia Microbiana/métodos , Controle de Qualidade , Bactérias/crescimento & desenvolvimento , China , Contagem de Colônia Microbiana/normas , Laboratórios/normas
10.
Wei Sheng Yan Jiu ; 44(3): 382-6, 2015 May.
Artigo em Zh | MEDLINE | ID: mdl-26137614

RESUMO

OBJECTIVE: To evaluate the antimicrobial resistance of Vibrio parahaemolyticus isolated from shellfish and its habitat in Sichuan, Fujian and Guangxi. METHODS: The susceptibility of 186 isolates of Vibrio parahaemolyticus to 8 antibiotics were determined by broth microdilution susceptibility test. The antibiotics of ampicillin, cefotaxime, ceftazidime, gentamicin, tetracycline, chloramphenicol, ciprofloxacin and trimethoprim/sulfamethoxazole were used. RESULTS: The antibiotic resistance rate were 69.35% in which ampicillin resistance was the most prevalent. The geometric mean of ampicillin MIC value of all isolates was greater than the interpretation value of resistance. Among the 186 tested isolates, the multiple antibiotic resistance and/or intermediate resistance was 4. All strains were 100% sensitive to cefotaxime, ceftazidime, chloramphenicol and ciprofloxacin. The ampicillin susceptibility spectrum of aquaculture farm was the highest among the three sectors as 73.68% and Sichuan was the highest among the three provinces as 70.94% although there were no significant differences. There were 44 samples out of which 2 and above strains were isolated, and the susceptibility spectrum polymorphism rate of strains isolated from the same sample was 77.27% (34/44). CONCLUSION: The ampicillin resistance rate is relatively high, and shellfish habitat may be the main source of antimicrobial resistance of Vibrio parahaemolyticus. There is an urgent need to strengthen the surveillance and management of Vibrio parahaemolyticus in the shellfish breeding process.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Vibrio parahaemolyticus/efeitos dos fármacos , Animais , Anti-Infecciosos , China , Cloranfenicol/farmacologia , Ciprofloxacina/farmacologia , Ecossistema , Gentamicinas , Testes de Sensibilidade Microbiana , Moluscos , Frutos do Mar , Vibrioses/tratamento farmacológico , Vibrioses/microbiologia , Vibrio parahaemolyticus/isolamento & purificação
11.
J Struct Biol ; 188(3): 233-9, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25449315

RESUMO

Dephospho-CoA kinase (DPCK; EC 2.7.1.24) catalyzes the final step in the coenzyme A biosynthetic pathway. DPCK transfers a phosphate group from ATP to the 3-hydroxyl group of the ribose of dephosphocoenzyme A (dCoA) to yield CoA and ADP. Upon the binding of ligands, large conformational changes is induced in DPCKs, as well as in many other kinases, to shield the bound ATP in their catalytic site from the futile hydrolysis by bulk water molecules. To investigate the molecular mechanisms underlying the phosphoryl transfer during DPCK catalytic cycle, we determined the crystal structures of the Legionellapneumophila DPCK (LpDPCK) both in its apo-form and in complex with ATP. The structures reveal that LpDPCK comprises of three domains, the classical core domain, the CoA domain, and the LID domain, which are packed together to create a central cavity for substrate-binding and enzymatic catalysis. The binding of ATP induces large conformational changes, including a hinge-bending motion of the CoA binding domain and the "helix to loop" conformational change of the P-loop. Finally, modeling of a dCoA molecule to the enzyme provides insights into the catalytic mechanism of DPCK.


Assuntos
Legionella pneumophila/metabolismo , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Sequência de Aminoácidos , Sítios de Ligação , Cristalografia por Raios X , Modelos Moleculares , Conformação Proteica
12.
Zhonghua Yu Fang Yi Xue Za Zhi ; 48(8): 731-5, 2014 Aug.
Artigo em Zh | MEDLINE | ID: mdl-25388472

RESUMO

OBJECTIVE: To develop a RT-PCR method for a rapid and sensitive detection of Salmonella in poultry samples. METHODS: The RT-PCR method was established and its specificity was testified on the basis of invA gene. Serial 10-fold diluted pure suspension culture of CMCC 50041 was detected by RT-PCR, the standard curve was constructed and the amplification efficiency was calculated. Artificially contaminated experiment was done, six artificially-inoculated samples containing final concentration of Salmonella CMCC 50041 (1, 10, 10(2), 10(3), 10(4), 10(5) and 10(6) CFU per 25 g poultry samples) were prepared respectively. All the samples were incubated for 0, 4, 8, 12 and 18 h and the DNA was extracted for RT-PCR detection, meanwhile by PCR detection and the traditional method. The sensitiveness and specificity were compared among the three methods. At the same time, 16 samples of retail whole poultry were collected from markets and detected by the above three methods as well, and thereby to further compare the positive detection among the three methods. RESULTS: The established RT-PCR method was specific for the detection of Salmonella. The sensitivity was 5.2×10(3) CFU/ml for pure Salmonella culture without enrichment. Correlation coefficients of standard curves constructed using the Ct versus log value of concentration of Salmonella showed good linearity over a 8-log dynamic range (5.2×10(3)-5.2×10(10) CFU/ml), with the R(2) at 0.999. RT-PCR detection limit for artificially contaminated samples after enriching for 12 h was 1 CFU/25 g sample, which was the same with the limit of PCR and 10 times more sensitive than the limit of traditional method. Standard curve of sample after enrichment for 12 h was established. Seven of 16 samples were detected positive by RT-PCR, which were also tested positive by PCR, while only five samples were positive by traditional method. The positive ones were quantitatively analyzed using standard curve of sample and determined the initial Salmonella numbers of CFU/25 g. CONCLUSION: The established RT-PCR technology was simple, rapid, sensitive and specific, which was suitable to quickly detect Salmonella in poultry samples.


Assuntos
Microbiologia de Alimentos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Salmonella , Animais , Proteínas de Bactérias , Aves Domésticas , Sensibilidade e Especificidade
13.
Wei Sheng Yan Jiu ; 43(4): 608-13, 2014 Jul.
Artigo em Zh | MEDLINE | ID: mdl-25199290

RESUMO

OBJECTIVE: To characterize and investigate the molecular types of Campylobacter jejuni isolated from slaughter chicken carcass, which would provide scientific data for campylobacter food poisoning traceability. METHODS: Biochemical and molecular biological methods were used for screening and identification of isolates from chicken special monitoring networks. Campylobacter Genus-specific primers 16S rRNA and species-specific primers MapA and CeuE were designed to perform a multiplex PCR to identify these isolated strains. Pulsed-field gel electrophoresis (PFGE) was employed to type Campylobacter jejuni isolates by digesting with restriction endonuclease Sma I and Kpn I respectively. Fingerprints of these isolates were analyzed by the software BioNumerics. RESULTS: 72 out of 81 isolates were confirmed as Campylobacter jejuni by biochemical test combined with PCR. 48 patterns were obtained from PFGE with Sma I and Kpn I. 72 isolated strains were divided into 13 clusters (A-M) according to 63.9% similarity by cluster analysis. Isolates from different provinces were distributed in 13 clusters and each cluster contained 1 to 11 patterns. The results showed that the 72 strain patterns distribution had complete regional homology, namely strains in the same pattern were from a single province. CONCLUSION: The comprehensive analysis of Sma I and Kpn I results may help improving the resolution of PFGE, increasing the accuracy of typing and reliability of traceability.


Assuntos
Campylobacter jejuni/isolamento & purificação , Eletroforese em Gel de Campo Pulsado , Doenças Transmitidas por Alimentos , Animais , Infecções por Campylobacter , Campylobacter jejuni/genética , Galinhas , Primers do DNA , Contaminação de Alimentos , Carne , Reação em Cadeia da Polimerase , RNA Ribossômico 16S , Reprodutibilidade dos Testes
14.
Wei Sheng Yan Jiu ; 43(2): 177-83, 2014 Mar.
Artigo em Zh | MEDLINE | ID: mdl-24868965

RESUMO

OBJECTIVE: To develop a real-time PCR method for detection Listeria monocytogenes in pork samples. METHODS: Listeria monocytogenes specific primers and Taqman probe were chosen on the basis of hlyA gene. Real-time PCR method was developed and its specificity was proved. Serial 10-fold diluted pure suspension culture of CMCC 540004 were detected by real-time PCR, and standard curve was constructed. Artificially contaminated experiment was done, six artificially-inoculated samples containing final concentration of Listeria monocytogenes CMCC 540004 (1.3 x 10(0), 1.3 x 10(1), 1.3 x 10(2), 1.3 x 10(3), 1.3 x 10(4), 1.3 x 10(5) and 1.3 x 10(6) CFU per 25 g pork samples) were preparated respectively, meanwhile one sample without inoculation was as control of background value. All the samples were incubated in LB1 enrichment for 24 h and then take 0.1 ml culture solutions to 10 ml LB2 enrichment for 18 - 24 h. All the samples were incubated for 0, 4, 8, 12, 18, 24, 30, 36 and 46 h, and detected Listeria monocytogenes bacteria by PCR, respectively. Twenty-four samples of retail pork were collected from markets in Beijing and detected by the above three methods. RESULTS: Real-time PCR method established was specific for the detection of Listeria monocytogenes. The sensitivity was 1.3 x 10(3) CFU/ml for pure culture without enrichment. Real-time PCR detection limit for artificially contaminated samples after enriching for 24 h was 1.3 CFU/ 25 g, which is the same with the limit of PCR and traditional method after enrichment for 46 h. Standard curve of sample after enrichment for 24 h was established. The positive rate out of total 24 samples was 70.83% (17/24) by real-time PCR, which is the same with the result of PCR and traditional method. The positive ones were quantitative analyzed using standard curve of sample and determined the initial Listeria monocytogenes numbers of CFU/25 g. CONCLUSION; The established real-time PCR technology was simple, rapid, sensitive and specific, which was suitable to rapid detect Listeria monocytogenes in pork samples and the process was finished in 27 h.


Assuntos
Contaminação de Alimentos , Listeria monocytogenes/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real , Animais , Microbiologia de Alimentos , Listeria monocytogenes/genética , Carne/microbiologia , Reação em Cadeia da Polimerase , Sensibilidade e Especificidade , Suínos
15.
Wei Sheng Yan Jiu ; 43(3): 430-4, 2014 May.
Artigo em Zh | MEDLINE | ID: mdl-24964623

RESUMO

OBJECTIVE: To survey the fungi contamination of different feed ingredients in China. METHODS: Soybean meal, cottonseed meal, wheat bran and distillers dried grains with soluble (DDGS) were collected from feed enterprises in different part of the country. Feed ingredient samples were diluted and inoculated and the key factors were screened which influenced the isolation. RESULTS: Potato dextrose agar (containing chloramphenicol 0.1 g/L) and 10(-1) dilution were the optimum culture medium and dilution respectively. The range of fungi contamination was from 31% (DDGS) to 88% (wheat bran). The fungi contamination frequencies of feed ingredients varied from region to region, and varied from kind to kind. The contamination of Aspergillus flavus and Fusarium spp. were also different in the regions and sample types. The average contamination percentage of Aspergillus flavus (25%) is higher than Fusarium spp. (11%), and their contamination level is highest in northeast China and lowest in south China, wheat bran and cottonseed meal were the highest and DDGS was the lowest. CONCLUSION: The fungi contamination, including Aspergillus flavus and Fusarium spp. of feed ingredients all over the country should be pay more attention. It is recommended that prevention of feed ingredients from fungi contamination is needed.


Assuntos
Ração Animal , Contaminação de Alimentos , Fungos , Aspergillus flavus , China , Grão Comestível , Microbiologia de Alimentos , Fusarium , Glycine max
16.
Heliyon ; 10(1): e23930, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38226219

RESUMO

The natural killer (NK) cell population is unique because it consists of innate lymphocytes capable of detecting and eliminating tumors and virus-infected cells. This research aims to identify a new prognostic signal in breast cancer (BRCA) based on NK-cell-related genes (NKRGs). A variety of sequencing and gene mutation data, along with clinical information, were collected from The Cancer Genome Atlas (TCGA) and Gene Expression Database (GEO). COX regression and least absolute shrinkage and selection operator (LASSO) Cox regression analyses were conducted to identify prognostic genes. In addition, the immune-related analysis was performed to evaluate the association between the immune microenvironment and clusters and risk model. The Edu assay, colony assay, wound healing assay, and transwell assay were performed to evaluate the cell proliferative and invasive abilities. A 4-NKRG-based prognostic model was constructed. Patients in high-risk groups were associated with poorer OS in TCGA and GSE42568. Further, a nomogram was constructed for better prediction of the prognosis of patients with BRCA. Finally, it was discovered that the over-expression of IFNE could suppress the proliferative and invasive abilities of BRCA cells, which might be a promising biomarker for patients with BRCA. As a result, we developed a novel 4-NKRG signal and nomogram capable of predicting the prognosis of patients with BRCA. Additionally, this model was closely associated with the immune microenvironment, which opened new therapeutic avenues for the treatment of cancer in the future.

17.
Gene ; 903: 148211, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38280496

RESUMO

Solute carrier family 12 member 8 (SLC12A8) is a nicotinamide mononucleotide transporter. Despite emerging evidence supporting its potential involvement in oncogenesis, a systematic pan-cancer analysis of SLC12A8 has not been performed. Thus, this research aimed to explore the prognostic implications of SLC12A8 and assess its possible immune-related functions across 33 different tumor types. And multiple datasets were retrieved from the databases of TCGA, GTEx, Broad Institute CCLE, TISCH, HPA, and GDSC2. After this data acquisition, bioinformatics analyses were conducted to assess the potential involvement of SLC12A8 in cancer pathogenesis. These analyses focused on examining the relationship between SLC12A8 and prognosis, drug sensitivity, chemotherapy response, immune checkpoints (ICPs), immune cell infiltration, and immunotherapy efficacy across various tumor types. Furthermore, experimental methods such as EdU assay, wound healing assay, and transwell assay were conducted to evaluate the cell proliferative and invasive abilities. Finally, the data analysis demonstrated that SLC12A8 was differentially expressed and predicted unfavorable survival outcomes in the majority of the tumor types in the TCGA dataset. Furthermore, a notable upregulation in the expression of SLC12A8 mRNA and protein was observed in cancer tissues compared to normal tissues. Additionally, the SLC12A8 levels demonstrated a strong association with ICPs, chemokines, immune-activating genes, immune-suppressive genes, chemokine receptors, chemotherapy response, and immunotherapy efficacy. In vitro experiments substantiated that knockdown of SLC12A8 restricted the malignant phenotypes of MDA-MB-231 and BT-549 cells. So SLC12A8 holds promise as a cancer biomarker with the capacity to interact with other ICPs to synergistically regulate the immune microenvironment. Thus, the identification of SLC12A8 contributes to the development of novel therapeutic strategies for enhancing the efficacy of immunotherapy.


Assuntos
Neoplasias , Humanos , Prognóstico , Neoplasias/genética , Neoplasias/terapia , Carcinogênese , Biomarcadores Tumorais/genética , Imunoterapia , Microambiente Tumoral/genética , Simportadores de Cloreto de Sódio-Potássio
18.
Chemosphere ; 323: 138182, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36868420

RESUMO

Thesolid oxide fuel cell (SOFC), as an economically friendly power generation system, shows a promising prospect for the future while hydrogen supply as its fuel is one of the main challenges. In this paper, an integrated system is described and evaluated by energy, exergy, and exergoeconomic, aspects. To find an optimum design state three models were analyzed to reach higher energy and exergy efficiency while system cost is at its lower value. After the first and main models, a Stirling engine reuses the first model's waste heat to generate power and enhance efficiency. In the last model, a proton exchange membrane electrolyzer (PEME) is considered for hydrogen production purposes by using the surplus power of the Stirling engine. The components validation is performed in comparison with the data presented by related studies. Optimization is applied by exergy efficiency, total cost, and hydrogen production rate considerations. The results show that the total cost of the model (a), (b), and (c) is 30.36 ($/GJ), 27.48 ($/GJ), and 33.82 ($/GJ), and the energy efficiency is 31.6%, 51.51%, 46.61% and the exergy efficiency is 24.07%, 33.0.9%, 29.28% respectively with the cost of at the optimum condition achieved by 2708 A/m2 current density, 0.84 utilization factor, 0.38 recycling anode ratio, 1.14 air blower and 1.58 fuel blower pressure ratio. The optimum rate of hydrogen production will be 138.2 kg/day and the overall product cost will be 57.58 $/GJ. In general, the proposed integrated systems show a good performance in both thermodynamics and environmental and economic aspects.


Assuntos
Óxidos , Resíduos Sólidos , Biomassa , Termodinâmica , Hidrogênio
19.
Chemosphere ; 334: 138935, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37211169

RESUMO

In the present article, a green and efficient multi-generation system equipped with proton exchange membrane (PEM) fuel cells as the main mover is presented and thoroughly examined. The proposed novel approach dramatically reduces the amount of carbon dioxide produced by using biomass as the primary energy source for PEM fuel cells. The waste heat recovery method is offered as a passive energy enhancement strategy for efficient and cost-effective output production. It uses the extra heat generated by the PEM fuel cells to produce cooling through the chillers. In addition, the thermochemical cycle is included to recover the waste heat from syngas exhaust gases and produce hydrogen, which will significantly help the process of going green transition. The suggested system's effectiveness, affordability, and environmental friendliness are assessed via a developed engineering equation solver program code. Additionally, the parametric analysis assesses the impact of major operational factors on the model's performance from thermodynamic, exergo-economic, and exergo-environmental indicators. According to the results, the suggested efficient integration achieves an acceptable total cost rate and environmental impact while obtaining high energy and exergy efficiencies. The results further reveal that the biomass moisture content is significant since it highly impacts the system's indicators from various aspects. From the conflictive changes between the exergy efficiency and exergo-environmental metrics, it can be concluded that choosing a proper design condition satisfying more than one aspect is highly important. According to the Sankey diagram, the worst equipment from the energy conversion quality is gasifier and fuel cells, with the highest irreversibility rate of 8 kW and 6.3 kW, respectively.


Assuntos
Fontes de Energia Elétrica , Hidrogênio , Prótons , Dióxido de Carbono/química , Gases/análise , Termodinâmica
20.
Chemosphere ; 328: 138606, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37023903

RESUMO

The significant growth of the global population, as well as the increase in energy demand and the limitations of energy generation from fossil fuels, have become a serious challenge over the world. To address these challenges, renewable energies like biofuels are recently found as a proper alternative to conventional fuels. Although biofuel production by using various techniques such as hydrothermal liquefaction (HTL) is considered one of the most promising methods to provide energy, the challenges correlated to its progression and development are still striking. In this investigation, the HTL method was employed to produce biofuel from municipal solid waste (MSW). In this regard, the effect of various parameters such as temperature, reaction time and waste-to-water ratio on mass and energy yield were assessed. It should be stressed that the optimization of biofuel production has been accomplished by the Box-Behnken method using Design Expert 8 software. Based on the results, biofuel production has an upward trend by increasing temperature to 364.57 °C and reaction time to 88.23 min Whereas, there is an inverse relationship between the biofuel waste-to-waterater ratio, in both the context of mass and energy yield.


Assuntos
Biocombustíveis , Resíduos Sólidos , Águas Residuárias , Temperatura , Biomassa , Água
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