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1.
ISA Trans ; 150: 92-106, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38763785

RESUMO

The proliferation of virtual synchronous generator (VSG) technology within series-compensated double-fed induction generator (DFIG)-based wind farms is substantially hampered by the attendant risk of subsynchronous control interaction (SSCI), resulting in a significant research deficiency on systematic control interaction analysis and the development of mitigation strategies. The paper proposes an advanced active disturbance rejection control (ADRC) framework, incorporating real-time compensation mechanisms to mitigate the inadequate suppression efficacy attributable to the VSG's diminished output impedance. Initially, the mathematical expression for the VSG output impedance is rigorously deduced, and the positive damping attributes of the VSG in relation to SSCI are elucidated from the perspective of underlying mechanistic principles. Subsequently, the suppressive mechanism of SSCI by the ADRC is revealed in the context of VSG involvement, and the consequent augmentation of SSCI attributed to PI control is systematically derived. In immediate succession, the quanta of oscillation and inductive cross-coupling are encapsulated as the system's aggregate disturbance, thereby streamlining the ADRC to its primary order configuration, permitting the utilization of an extended state observer (ESO) for the dynamic estimation of said disturbance. Furthermore, a fractional-order filter function is instituted to engineer an augmented ESO, which refines the output voltage of the grid-side converter. Concurrently, a meticulous discourse on the rectification strategy for the proposed ESO parameters and its stability ensues. Ultimately, the efficacy of the mechanism analysis, alongside the robustness of the proffered control strategy for SSCI mitigation under diverse perturbation conditions, is corroborated via impedance evaluation and time-domain simulation.

2.
Arch Oral Biol ; 153: 105720, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37285682

RESUMO

OBJECTIVE: This study aimed to explore the key genes, metabolites, and pathways that influence periodontitis pathogenesis by integrating transcriptomic and metabolomic studies. DESIGN: Gingival crevicular fluid samples from periodontitis patients and healthy controls were collected for liquid chromatography/tandem mass-based metabolomics. RNA-seq data for periodontitis and control samples were obtained from the GSE16134 dataset. Differential metabolites and differentially expressed genes (DEGs) between the two groups were then compared. Based on the protein-protein interaction (PPI) network module analysis, key module genes were selected from immune-related DEGs. Correlation and pathway enrichment analyses were performed for differential metabolites and key module genes. A multi-omics integrative analysis was performed using bioinformatic methods to construct a gene-metabolite-pathway network. RESULTS: From the metabolomics study, 146 differential metabolites were identified, which were mainly enriched in the pathways of purine metabolism and Adenosine triphosphate binding cassette transporters (ABC transporters). The GSE16134 dataset revealed 102 immune-related DEGs (458 upregulated and 264 downregulated genes), 33 of which may play core roles in the key modules of the PPI network and are involved in cytokine-related regulatory pathways. Through a multi-omics integrative analysis, a gene-metabolite-pathway network was constructed, including 28 genes (such as platelet derived growth factor D (PDGFD), neurturin (NRTN), and interleukin 2 receptor, gamma (IL2RG)); 47 metabolites (such as deoxyinosine); and 8 pathways (such as ABC transporters). CONCLUSION: PDGFD, NRTN, and IL2RG may be potential biomarkers of periodontitis and may affect disease progression by regulating deoxyinosine to participate in the ABC transporter pathway.


Assuntos
Multiômica , Periodontite , Humanos , Periodontite/genética , Mapas de Interação de Proteínas/genética , Perfilação da Expressão Gênica/métodos , Redes Reguladoras de Genes , Biologia Computacional/métodos
3.
Artigo em Inglês | MEDLINE | ID: mdl-36757036

RESUMO

Since the authors are not responding to the editor's requests to fulfill the editorial requirement, therefore, the article has been withdrawn from the journal "Current Cancer Drug Targets"Bentham Science apologizes to the readers of the journal for any inconvenience this may have caused.The Bentham Editorial Policy on Article Withdrawal can be found at https://benthamscience.com/editorial-policies-main.php. BENTHAM SCIENCE DISCLAIMER: It is a condition of publication that manuscripts submitted to this journal have not been published and will not be simultaneously submitted or published elsewhere. Furthermore, any data, illustration, structure or table that has been published elsewhere must be reported, and copyright permission for reproduction must be obtained. Plagiarism is strictly forbidden, and by submitting the article for publication the authors agree that the publishers have the legal right to take appropriate action against the authors, if plagiarism or fabricated information is discovered. By submitting a manuscript the authors agree that the copyright of their article is transferred to the publishers if and when the article is accepted for publication.

4.
Plant J ; 108(6): 1644-1661, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34623717

RESUMO

Brown coloration and a rough appearance as russet and semi-russet (partial russet) are features unique to the popular Asian sand pear (Pyrus pyrifolia Nakai). The degree of russeting is different between different genotypes. Russeting is sensitive to water fluctuations, where excessive rainwater can trigger/stimulate its development. However, the molecular mechanism of russeting is currently unclear. Here, we employed multi-omics, i.e., metabolomics, transcriptomics, and proteomics, and analyzed the effect of different sand pear genotypes and artificial rainfall on russeting of pear fruits. This led to the identification of 79, 64, and 29 differentially produced/expressed metabolites, transcripts, and proteins that are involved in the biosynthesis of suberin, phenylpropane, cutin, and waxes. Further analysis of these differentially expressed genes and their encoded proteins revealed that four of them exhibited high expression at both transcript and protein levels. Transient expression of one such gene, PbHHT1 (accession number 103966555), which encodes ω-hydroxypalmitate-O-feruloyl transferase, in young green non-russet fruits triggered premature suberization in the russeting pear genotypes. This coincided with increased production of 16-feruloyloxypalmitic acid, a conjugated compound between phenols and esters during the polymerization for suberin formation. Collectively, our data from the combined three omics demonstrate that russeting in sand pear is a complex process involving the biosynthesis and transport of suberin and many other secondary metabolites.


Assuntos
Frutas/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Pyrus/fisiologia , China , Frutas/genética , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas , Genótipo , Metabolômica , Microscopia Eletrônica de Varredura , Pyrus/genética , Pyrus/metabolismo
5.
Chin J Cancer Res ; 32(5): 631-644, 2020 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-33223758

RESUMO

OBJECTIVE: This study aimed to determine the impact of type 2 diabetes mellitus (T2DM) on clinical outcomes of gastric cancer (GC) patients and explore whether metformin use and good glycemic control could reverse it. METHODS: Clinicopathologic data of consecutive GC patients who underwent gastrectomy at Nanfang Hospital between October 2004 and December 2015 were included. Propensity score matching (PSM) was performed to balance the important factors of the disease status between non-T2DM and T2DM group. The last follow-up time was January 2019. RESULTS: A total of 1,692 eligible patients (1,621 non-T2DM vs. 71 T2DM) were included. After PSM, non-T2DM group (n=139) and T2DM group (n=71) were more balanced in baseline variables. The 5-year cancer-specific survival (CSS) rate in T2DM group (47.0%) was inferior to that in non-T2DM group (58.0%), but did not reach statistical significance [hazard ratio (HR)=1.319, 95% confidence interval (95% CI): 0.868-2.005, P=0.192]. While the 5-year progress-free survival (PFS) rate of T2DM group (40.6%) is significantly worse than that in non-T2DM group (56.3%) (HR=1.516, 95% CI: 1.004-2.290, P=0.045). Univariate and multivariate analyses showed that T2DM was an independent risk factor for PFS but not for CSS. In T2DM group, metformin use subgroup was associated with superior 5-year CSS and PFS in compared with non-metformin use subgroup, although the difference was not statistically significant (5-year CSS: 48.0%vs. 45.4%, HR=0.680, 95% CI: 0.352-1.313, P=0.246; 5-year PFS: 43.5%vs. 35.7%, HR=0.763, 95% CI: 0.400-1.454, P=0.406). The 5-year CSS rate was 47.5% in good glycemic control subgroup and 44.1% in poor glycemic control subgroup (HR=0.826, 95% CI: 0.398-1.713, P=0.605). And both two subgroups yielded a similar 5-year PFS rate (42.2%vs. 36.3%, HR=0.908, 95% CI: 0.441-1.871, P=0.792). CONCLUSIONS: DM promoted disease progress of GC after gastrectomy but had not yet led to the significant discrepancy of CSS. For GC patients with T2DM, metformin use was associated with superior survival but without statistical significance, while better glycemic control could not improve the prognosis.

6.
Heliyon ; 5(9): e02463, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31687562

RESUMO

Landslide-debris flow is a sudden geological hazard in mountain areas, which is characterized with large scale, fast speed and wide impact range, and often causes disastrous accidents. In this study, an indoor sliding chute test was used to study the movement process of the landslide-debris flow and its accumulation pattern in the valley, taking into account the initiated gradient and particle size distribution. Besides, the model test was reproduced by PFC and the numerical models were constructed to fit the actual situation of landslide-debris flow. The results show that the collision of particles occurs during the movement of landslide-debris flow, and obvious sorting phenomena occur in the final deposit. Coarse particles distribute in the front and surface of the deposit while fine particles distribute in the back and bottom. The initiated angle has a certain effect on the morphology of the deposit: larger initiated angle makes the deposit closer to the opposite bank of the valley. Particle gradation has a significant impact on the form and distribution of deposit as well, with the increase of the proportion of coarse particles, the deposit of fine particles shrinks to the center of the rear edge, the profile of the deposit is more flat and uneven, the deposit is closer to the opposite bank of the valley, and the angle of the deposit profile increases significantly.

7.
J Microbiol Biotechnol ; 28(11): 1791-1799, 2018 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-30199923

RESUMO

Weaning stress can affect the growth performance and intestinal health of piglets. Dietary alternatives to antibiotics, such as dietary probiotics, especially those containing multiple microbial species, are a preventive strategy for effectively controlling post-weaning diarrhea. In this study, we investigated forty-eight crossbred piglets in three treatment groups for 21 days: the control and experimental groups were supplemented with Enterococcus faecium DSM 7134, Bacillus subtilis AS1.836 plus Saccharomyces cerevisiae ATCC 28338 (EBS) or Lactobacillus paracasei L9 CGMCC No. 9800 (EBL). On day 21, weaned piglets supplemented with two kinds of probiotic complexes showed increased growth performance and significantly reduced post-weaning diarrhea (p < 0.05). The EBS treatment increased acetic acid and propionic acid in the feces (p < 0.05), and the EBL treatment increased fecal acetic acid, propionic acid, butyrate and valerate (p < 0.05). Moreover, the fecal microbiota of the piglets changed markedly in EBL treatment. The addition of EBS and EBL may have similar effects on the prevention of diarrhea by improving the intestinal morphology and regulating the microbiota during the weaning period.


Assuntos
Bactérias , Diarreia/veterinária , Suplementos Nutricionais , Probióticos , Doenças dos Suínos/prevenção & controle , Suínos/crescimento & desenvolvimento , Ração Animal/análise , Ração Animal/microbiologia , Animais , Bacillus subtilis , Diarreia/prevenção & controle , Suplementos Nutricionais/microbiologia , Ácidos Graxos Voláteis/análise , Fezes/química , Fezes/microbiologia , Lacticaseibacillus paracasei , Microbiota/genética , Saccharomyces cerevisiae , Suínos/metabolismo , Suínos/microbiologia , Desmame
8.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 30(2): 202-204, 2018 Feb 10.
Artigo em Chinês | MEDLINE | ID: mdl-29770666

RESUMO

OBJECTIVE: To evaluate the molluscicidal effect of niclosamidate against Oncomelania hupensis in laboratory and explore its mechanism by determining the enzyme activities of six important enzymes in snail soft tissues. METHODS: O. hupensis snails were treated with niclosamidate at the concentration of 1.25 mg/L for 24 h and the snail soft tissues were separated and prepared for analysis. The enzyme activities of NOS, AChE, SDH, LDH, ACP and AKP were determined by ultraviolet spectrophotometry. The morphology of the snail soft tissue was also observed. RESULTS: Niclosamidate exhibited a potent molluscicidal effect against O. hupensis at the concentration of 5.00 mg/L with a mortality of 96.67% by the immersion method in laboratory. After immersed with niclosamidate (1.25 mg/L) for 24 h, the enzyme activities of NOS, AChE, ACP and AKP were significantly decreased compared with those of the controls (all P < 0.01). There were no significant changes observed in the enzyme activities of SDH and LDH (both P > 0.05). CONCLUSIONS: Niclosamidate possesses a potent molluscicidal effect against O. hupensis and its molluscicidal mechanism is probably by affecting the transmission of neurotransmitters, interfering with the circulation, metabolism and motor functions that require NO, and hindering the digestion and absorption of nutriments, which eventually result in the death of the snails.


Assuntos
Moluscocidas , Salicilanilidas , Caramujos , Animais
9.
Medicine (Baltimore) ; 96(49): e8932, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29245259

RESUMO

BACKGROUND: Catheter-related bladder discomfort (CRBD) to an indwelling urinary catheter is defined as a painful urethral discomfort, resistant to conventional opioid therapy, decreasing the quality of postoperative recovery. According to anatomy, the branches of sacral somatic nerves form the afferent nerves of the urethra and bladder triangle, which deriving from the ventral rami of the second to fourth sacral spinal nerves, innervating the urethral muscles and sphincter of the perineum and pelvic floor; as well as providing sensation to the penis and clitoris in males and females, which including the urethra and bladder triangle. Based on this theoretical knowledge, we formed a hypothesis that CRBD could be prevented by pudendal nerve block. OBJECTIVE: To evaluate if bilateral nerve stimulator-guided pudendal nerve block could relieve CRBD through urethra discomfort alleviation. DESIGN AND SETTING: Single-center randomized parallel controlled, double blind trial conducted at West China Hospital, Sichuan University, China. PARTICIPANTS: One hundred and eighty 2 male adult patients under general anesthesia undergoing elective trans-urethral resection of prostate (TURP) or trans-urethral resection of bladder tumor (TURBT). Around 4 out of 182 were excluded, 178 patients were randomly allocated into pudendal and control groups, using computer-generated randomized numbers in a sealed envelope method. A total of 175 patients completed the study. INTERVENTION: Pudendal group received general anesthesia along with nerve-stimulator-guided bilateral pudendal nerve block and control group received general anesthesia only. MAIN OUTCOME MEASURES: Incidence and severity of CRBD; and postoperative VAS score of pain. RESULTS: CRBD incidences were significantly lower in pudendal group at 30 minutes (63% vs 82%, P = .004), 2 hours (64% vs 90%, P < .000), 8 hours (58% vs 79%, P = .003) and 12 hours (52% vs 69%, P = .028) also significantly lower incidence of moderate to severe CRBD in pudendal group at 30 minutes (29% vs 57%, P < .001), 2 hours (22% vs 55%, P < .000), 8 hours (8% vs 27%, P = .001) and 12 hours (6% vs 16%, P = .035) postoperatively. The postoperative pain score in pudendal group was lower at 30 minutes (P = .003), 2 hours (P < .001), 8 hours (P < .001), and 12 hours (P < .001), with lower heart rate and mean blood pressure. One patient complained about weakness in levator ani muscle. CONCLUSION: General anesthesia along with bilateral pudendal nerve block decreased the incidence and severity of CRBD for the first 12 hours postoperatively.


Assuntos
Cateteres de Demora/efeitos adversos , Bloqueio Nervoso/métodos , Nervo Pudendo , Ressecção Transuretral da Próstata , Neoplasias da Bexiga Urinária/cirurgia , Cateteres Urinários/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Anestesia Geral , Método Duplo-Cego , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Resultado do Tratamento
10.
Nat Prod Res ; 30(23): 2707-2711, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26784285

RESUMO

Elsholtzia densa Benth. is a traditional aromatic herb used in the pharmaceutical and flavouring industries. To analyse and compare the chemical composition, the oils and nonvolatile compounds in E. densa and Mosla chinensis Maxim. were extracted via hydrodistillation, solvent extraction or ultrasound-assisted extraction. Seventy-three volatile compounds in the volatile oil (0.35 ± 0.06%) obtained by E. densa via hydrodistillation were investigated by gas chromatography-mass spectrometer and compared based on different parameters. Also, the antioxidant activity and α-glucosidase inhibitory effects of the five sub-fractions of the methanolic extract were studied and the ethyl acetate sub-fraction (EC50 = 7.9 µg/mL) and petroleum ether sub-fraction (EC50 = 0.0955 mg/mL) showed the strongest activity, respectively. This study has provided a scientific basis for scientific collection, effective development, use of E. densa Benth., and suggested that it can be used as a potential source of antioxidants in food and a potential candidate for the management of type 2 diabetes mellitus.

11.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 34(5): 541-543, 2016 Oct 01.
Artigo em Chinês | MEDLINE | ID: mdl-28326719

RESUMO

Ectopic tooth is a common problem reported in clinics. Ectopic tooth generally occurs around its primary position, and long-distance displacement is rare. A case of ectopic maxillary premolar in palatal suture with a supernumerary tooth in the mentum region was reported in this study, and the relevant literature is presented in this paper.


Assuntos
Dente Pré-Molar , Dente Supranumerário , Queixo , Humanos , Má Oclusão , Suturas
12.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 32(6): 519-524, 2016 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-29926619

RESUMO

OBJECTIVE: Acute mountain sickness (AMS) is a common condition in individuals who ascend to altitudes over 2 500 m. There is no measurements that can reliably predict or diagnose this condition. We therefore determined whether pulse oximetry data are associated with the development of AMS and can help diagnose AMS. METHODS: We studied 58 young male undergraduates who traveled from Chongqing (300 m) to Lhasa (3 658 m) by train. We collected data on the ascent profiles and AMS symptoms based on the Lake Louise Score (LLS). The resting arterial oxygen saturation (R-SpO2) and pulse rate were then measured using finger pulse oximetry. RESULTS: In Golmud(2 800 m) and Tanggula(5 200 m), R-SpO2 was significantly lower in the AMS group than in the group without AMS (P<0.05). However, upon arrival in Lhasa (3 658 m), the R-SpO2 was higher in the AMS group than in the non-AMS group (P<0.05). In Tanggula, the change in the SpO2 (CR-SpO2) in the AMS group was higher than that in the non-AMS group (P<0.05). But in Lhasa, the CR-SpO2 in the AMS group was lower than that in the non-AMS group (P<0.05). We also monitored heart rate (HR) throughout the study. In Xining(2 200 m) and Golmud, the HRs in the AMS group were higher than those in the non-AMS group. However, the HRs in the AMS group were lower than those in the non-AMS group in Tanggula and Lhasa. CONCLUSIONS: Based on the results of this study, the R-SpO2 graph was not consistent. We can thus conclude that the utility of SpO2 remains limited in the diagnosis of AMS. The results suggest that using pulse oximetry to diagnose AMS is not valuable in people ascending to Lhasa on the Qinghai-Tibet train.


Assuntos
Doença da Altitude/diagnóstico , Oximetria , Oxigênio/sangue , Altitude , Humanos , Masculino , Tibet
13.
J Cell Biochem ; 116(1): 192-201, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25169669

RESUMO

Peroxisome proliferator-activated receptor-gamma (PPARG) is considered to be a central regulator of lipid metabolism in mammary cells. Adipose differentiation-related protein (ADRP), a member of PAT family (Perilipin, ADRP, TIP47 family), plays a key role in lipid accumulation in mammary gland. It has been found that PPARG significantly promoted lipid storage in goat mammary epithelial cells (GMEC), which was abolished after knockdown of ADRP gene. The results of real-time PCR, Western blot and luciferase reporter assay for goat ADRP promoter showed that ligand-activated PPARG up-regulated the ADRP gene expression and activity of ADRP promoter. Moreover, PPARG directly interacted with a PPRE (PPAR response element) spanning at -1003 to -990 on ADRP promoter. In this study, to our knowledge, we are the first to verify the function of PPARG on lipid storage on cellular level of goat mammary gland and our results revealed a novel pathway that PPARG may regulate lipid accumulation by controlling the expression of ADRP gene.


Assuntos
Células Epiteliais/metabolismo , Proteínas de Membrana/metabolismo , PPAR gama/metabolismo , Animais , Células Cultivadas , Cabras , Humanos , Metabolismo dos Lipídeos/genética , Metabolismo dos Lipídeos/fisiologia , Glândulas Mamárias Humanas/citologia , Proteínas de Membrana/genética , PPAR gama/genética , Perilipina-2
15.
J Hazard Mater ; 274: 41-5, 2014 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-24762699

RESUMO

The radiation hazards of radionuclide arising from the storage of nuclear weapons cannot be ignored to the operators. Ultrasonic standing wave methods can be considered as the green cleaning separation techniques with high efficiency. The application of ultrasonic standing wave methods for liquid radioactive wastes treatment requires solving many problems connected with the proper selection of the frequency and power of ultrasonic transducers, and the processing time, etc. Based on the model of one single suspended radioactive particle subjected to in the field of ultrasonic standing wave, the principle of the treatment of low-level radioactive wastewater by ultrasound was analyzed. The theoretical and simulation results show that under the action of ultrasonic standing wave, the particle will move toward the wave node plane, and the time of particle reaching the plane become shorter when the radius of particle and the frequency and power of ultrasound was enlarged. The experimental results show that the radioactive concentration of wastewater could be reduced from 400 Bq L(-1) to 9.3 Bq L(-1) and the decontamination efficiency was 97.68%. The decontamination efficiency could not be obviously improved by further increasing the treating time.


Assuntos
Ultrassom/métodos , Eliminação de Resíduos Líquidos/métodos , Poluentes Radioativos da Água , Águas Residuárias
16.
Clin Biochem ; 43(3): 253-8, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19833117

RESUMO

OBJECTIVES: Essential hypertension is considered to be a multifactorial trait resulting from the combined influence of environmental and genetic determinants. The aim of the study is to assess the association between the human AGTR1 gene and essential hypertension (EH) using a haplotype-based case-control study in Han Chinese subjects. DESIGN AND METHODS: Seven tag SNPs and the A1166C polymorphism of the AGTR1 gene were genotyped in 510 hypertension subjects and 510 normotensive subjects using PCR-RFLP method. RESULTS: Single SNP analyses indicated that the rs12695895 was significantly associated with hypertension, adjusted for covariates. Compared with the other haplotypes, Hap4 (AGGACTT) which carry the susceptible rs12695895 A allele was found to significantly increase the risk of EH with odds ratios equal to 1.84 (p=0.0002). CONCLUSIONS: The present results indicate that rs12695895 might be a genetic marker for EH and Hap4 (AGGACTT) was associated with hypertension in Han Chinese population.


Assuntos
Povo Asiático/genética , Predisposição Genética para Doença , Haplótipos , Hipertensão/genética , Polimorfismo Genético , Receptor Tipo 1 de Angiotensina/genética , Adulto , Idoso , Alelos , Pressão Sanguínea/genética , Pressão Sanguínea/fisiologia , Estudos de Casos e Controles , Feminino , Marcadores Genéticos , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade
17.
Open Cardiovasc Med J ; 1: 27-33, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18949088

RESUMO

Studies have shown that adult bone marrow derived stem cells (MSCs) can participate in repair of myocardial injury in adult hearts, as well as in cardiac growth during fetal development in utero. Yet, no studies have evaluated the role of MSCs with respect to normal growth or tissue repair in immature hearts after birth. The present study examines whether MSCs may participate in the myocardial growth and injury in the post-natal immature hearts. MSCs were isolated from adult Lewis rats and labeled with Lac-Z gene using retroviral vectors. These MSCs were injected systemically into groups of neonatal (NB=2days-old), immature (B=30days-old) and adult (A=>3months-old) isogeneic Lewis rats. Additionally, left coronary artery ligation was carried out in subgroups of immature (BL) and adult (AL) rats one week after MSCs injection. The hearts were harvested serially from 2-days to 6-weeks, stained with X-Gal for labeled MSCs. Cardiomyocyte phenotypic expression was evaluated by immunohistological staining for Troponin I-C and Connexin-43. Labeled MSCs were found to home into the bone marrow in all rats of different developmental stages. They could be recruited from bone marrow into the infarcted site of myocardium only in groups AL and BL. They were also capable of differentiating into cardiomyocyte phenotype after myocardial injury. In contrast to that reported in the developing fetus, MSCs did not appear to contribute to the growth of non-injured hearts after birth. However, they can be recruited from the bone marrow and regenerate damaged myocardium both in the adult and in the immature hearts.

18.
Int J Biochem Cell Biol ; 36(8): 1473-81, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15147726

RESUMO

AIM: To elucidate the interference effect of epigallocatechin-3-gallate (EGCG) on targets of nuclear factor kappaB (NF-kappaB) signal transduction pathway activated by EB virus encoded latent membrane protein 1 (LMP1) in nasopharyngeal carcinoma (NPC) cell lines. METHODS: The survival rates of CNE1 and CNE-LMP1 cell lines after the EGCG treatment were determined by MTT assay. NF-kappaB activation in CNE1 and CNE-LMP1 cells after EGCG treatment was analyzed by promoter luciferase reporter system. And then nuclear translocation of NF-kappaB (p65) after the EGCG treatment was analyzed by immunofluorescence and western blotting. Meanwhile, the changes of IkappaBalpha phosphorylation were observed after the EGCG treatment. EGFR promoter activity was analyzed by promoter luciferase reporter system and EGFR phosphorylation was observed by western blotting after the EGCG treatment. RESULTS: EGCG inhibited the survival rates of CNE1 and CNE-LMP1 cells and NF-kappaB activation caused by LMP1 in CNE-LMP1 cells. EGCG also suppressed the nuclear translocation of NF-kappaB (p65) and IkappaBalpha phosphorylation. Meanwhile, EGCG inhibited EGFR promoter activity and EGFR phosphorylation. CONCLUSIONS: EGCG inhibited not only the dose-dependent survival rate of NPC cells, but also the dose-dependent activation of NF-kappaB. This inhibition of LMP1-caused NF-kappaB activation was mediated via the phosphorylative degradation of its inhibitory protein IkappaBalpha, and then EGCG inhibited EGFR activity which was a downstream gene from NF-kappaB. This study suggests that interference effect of EGCG on targets of signal transduction pathway plays an important role in the anticancer function.


Assuntos
Catequina/análogos & derivados , Catequina/farmacologia , NF-kappa B/metabolismo , Transdução de Sinais , Proteínas da Matriz Viral/fisiologia , Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular , Receptores ErbB/genética , Humanos , Proteínas I-kappa B/metabolismo , Inibidor de NF-kappaB alfa , Neoplasias Nasofaríngeas/patologia , Regiões Promotoras Genéticas/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Fator de Transcrição RelA
19.
Plant Cell Physiol ; 45(12): 1882-8, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15653808

RESUMO

Two solanesyl diphosphate synthases, designated SPS1 and SPS2, which are responsible for the synthesis of the isoprenoid side chain of either plastoquinone or ubiquinone in Arabidopsis thaliana, were identified. Heterologous expression of either SPS1 or SPS2 allowed the generation of UQ-9 in a decaprenyl diphosphate synthase-defective strain of fission yeast and also in wild-type Escherichia coli. SPS1-GFP was found to localize in the ER while SPS2-GFP localized in the plastid of tobacco BY-2 cells. These two different subcellular localizations are thought to be the reflection of their roles in solanesyl diphosphate synthesis in two different parts: presumably SPS1 and SPS2 for the side chains of ubiquinone and plastoquinone, respectively.


Assuntos
Alquil e Aril Transferases/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimologia , Alquil e Aril Transferases/genética , Alquil e Aril Transferases/isolamento & purificação , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/isolamento & purificação , DNA Complementar/análise , DNA Complementar/genética , Retículo Endoplasmático/metabolismo , Escherichia/metabolismo , Dados de Sequência Molecular , Plastídeos/metabolismo , Plastoquinona/metabolismo , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico , Terpenos/metabolismo , Nicotiana/metabolismo , Ubiquinona/metabolismo , Leveduras/metabolismo
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