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1.
PLoS One ; 18(10): e0292004, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37812633

RESUMEN

Using information technology to extract emergency decision-making knowledge from emergency plan documents is an essential means to enhance the efficiency and capacity of emergency management. To address the problems of numerous terminologies and complex relationships faced by emergency knowledge extraction of water diversion project, a multi-feature graph convolutional network (PTM-MFGCN) based on pre-trained model is proposed. Initially, through the utilization of random masking of domain-specific terminologies during pre-training, the model's comprehension of the meaning and application of such terminologies within specific fields is enhanced, thereby augmenting the network's proficiency in extracting professional terminologies. Furthermore, by introducing a multi-feature adjacency matrix to capture a broader range of neighboring node information, thereby enhancing the network's ability to handle complex relationships. Lastly, we utilize the PTM-MFGCN to achieve the extraction of emergency entity relationships in water diversion project, thus constructing a knowledge graph for water diversion emergency management. The experimental results demonstrate that PTM-MFGCN exhibits improvements of 2.84% in accuracy, 4.87% in recall, and 5.18% in F1 score, compared to the baseline model. Relevant studies can effectively enhance the efficiency and capability of emergency management, mitigating the impact of unforeseen events on engineering safety.


Asunto(s)
Ingeniería , Ciencia de la Información , Tecnología de la Información , Agua
2.
PLoS One ; 17(1): e0262329, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34990468

RESUMEN

To overcome the low accuracy, poor reliability, and delay in the current drought prediction models, we propose a new extreme learning machine (ELM) based on an improved variational mode decomposition (VMD). The model first redefines the output of the hidden layer of the ELM model with orthogonal triangular matrix decomposition (QR) to construct an orthogonal triangular ELM (QR-ELM), and then introduces an online sequence learning mechanism (OS) into the QR-ELM to construct an online sequence OR-ELM (OS-QR-ELM), which effectively improves the efficiency of the ELM model. The mutual information extension method was then used to extend both ends of the original signal to improve the VMD end effect. Finally, VMD and OS-QR-ELM were combined to construct a drought prediction method based on the VMD-OS-QR-ELM. The reliability and accuracy of the VMD-OS-QR-ELM model were improved by 86.19% and 93.20%, respectively, compared with those of the support vector regression model combined with empirical mode decomposition. Furthermore, the calculation efficiency of the OS-QR-ELM model was increased by 88.65% and 85.32% compared with that of the ELM and QR-ELM models, respectively.


Asunto(s)
Sequías/prevención & control , Algoritmos , Aprendizaje Automático , Redes Neurales de la Computación , Reproducibilidad de los Resultados
3.
Cancer Biomark ; 21(3): 613-620, 2018 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-29278879

RESUMEN

Long non-coding RNAs (lncRNAs) were playing critical roles in tumorigenesis. However, in prostate cancer, the roles and mechanisms of lncRNAs especially ANRIL were largely unknown. We investigated the effects of ANRIL on the proliferation and migration of prostate cancer cells using CCK-8 assay and Transwell migration assay. Real-time PCR and western blotting assays were used to analyze the levels of ANRIL, let-7a, TGF-ß1, p-Smad2 and p-Smad7. Our results showed that ANRIL was significantly overexpressed in prostate cancer tissues compared with corresponding normal tissues. Knockdown of ANRIL significantly inhibited the proliferation and migration of prostate cancer LNCap, PC3 and DU145 cells. Knockdown of ANRIL significantly decreased the levels of TGF-ß1 and p-Smad2, and increased the level of p-Smad7 in prostate cancer LNCap cells. We further found that knockdown of ANRIL significantly enhanced the expression of let-7a, and rescue experiment found that let-7a inhibitor recovered the suppressive effects of ANRIL silencing on the proliferation and migration of prostate cancer LNCap, PC3 and DU145 cells. And let-7a inhibitor recovered the suppressive effects of ANRIL silencing on the activity of TGF-ß1/Smad signaling pathway in prostate cancer LNCap cells. Taken together, our findings indicated that overexpression of lncRNA ANRIL promoted the proliferation and migration of prostate cancer cells via regulating let-7a/TGF-ß1/Smad signaling pathway.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , MicroARNs/genética , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/metabolismo , ARN Largo no Codificante/genética , Transducción de Señal , Proteína smad7/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Técnicas de Silenciamiento del Gen , Humanos , Masculino , Neoplasias de la Próstata/patología
4.
Prep Biochem Biotechnol ; 46(4): 376-83, 2016 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-26176584

RESUMEN

The production of erythritol by Yarrowia lipolytica from low-cost substitutable substrates for high yield was investigated. Crude glycerol, urea, and NaCl related to osmotic pressure were the most significant factors affecting erythritol production. An artificial neural network model and genetic algorithm were used to search the optimal composition of the significant factors and locate the resulting erythritol yield. Medium with 232.39 g/L crude glycerol, 1.57 g/L urea, and 31.03 g/L NaCl led to predictive maximum erythritol concentration of 110.7 g/L. The erythritol concentration improved from 50.4 g/L to 109.2 g/L with the optimized medium, which was reproducible. Erythritol fermentation kinetics were investigated in a batch system. Multistep fermentation kinetic models with hyperosmotic inhibitory effects were developed. The resulting mathematical equations provided a good description of temporal variations such as microbial growth (X), substrate consumption (S), and product formation (P) in erythritol fermentation. The accordingly derived model is the first reported model for fermentative erythritol production from glycerol, providing useful information to optimize the growth of Y. lipolytica and contributing visual description for the erythritol fermentation process under high osmotic pressure, as well as improvement of productivity and efficiency.


Asunto(s)
Eritritol/biosíntesis , Fermentación , Glicerol/metabolismo , Yarrowia/metabolismo , Medios de Cultivo , Cinética , Concentración Osmolar
5.
Int J Endocrinol ; 2015: 642046, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26273300

RESUMEN

The BRAF(V600E) mutation is commonly found in papillary thyroid cancers (PTCs) at different frequencies in different regions. However, the association between the BRAF(V600E) mutation and clinicopathological features in Chinese PTC patients is unknown. A total of 543 Chinese patients with histologically confirmed PTC were enrolled in this study. For the BRAF mutation assay, the target fragments were amplified and sequenced with an ABI 3500 gene analyzer. In 170 of 543 samples (31.3%), the BRAF(V600E) mutation was detected. In the bivariate analysis, the BRAF(V600E) mutation showed an association with bilaterality, tumor size, extrathyroidal invasion, and lymph node metastases (LNM). However, in the multivariate analysis, the BRAF(V600E) mutation was positively related to only tumor size (>1 cm) and extrathyroidal invasion. In addition, the multivariate analysis also showed that the age at diagnosis (<45 y) and tumor size (>1 cm) were independent predictors for LNM. In this study, the BRAF(V600E) mutation is positively associated with worse prognostic factors, including larger tumor size and the tumor extending to the thyroid capsule or extrathyroidal region; however, it is not an independent predictor for LNM.

6.
J Microbiol Biotechnol ; 25(7): 1056-69, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25737116

RESUMEN

Osmotic pressure is a critical factor for erythritol production with osmophilic yeast. Protein expression patterns of an erythritol-producing yeast, Yarrowia lipolytica, were analyzed to identify differentially-expressed proteins in response to osmotic pressure. In order to analyze intracellular protein levels quantitatively, two-dimensional gel electrophoresis was performed to separate and visualize the differential expression of the intracellular proteins extracted from Y. lipolytica cultured under low (3.17 osmol/kg) and high (4.21 osmol/kg) osmotic pressures. Proteomic analyses allowed identification of 54 differentially-expressed proteins among the proteins distributed in the range of pI 3-10 and 14.4-97.4 kDa molecular mass between the osmotic stress conditions. Remarkably, the main proteins were involved in the pathway of energy, metabolism, cell rescue, and stress response. The expression of such enzymes related to protein and nucleotide biosynthesis was inhibited drastically, reflecting the growth arrest of Y. lipolytica under hyperosmotic stress. The improvement of erythritol production under high osmotic stress was due to the significant induction of a range of crucial enzymes related to polyols biosynthesis, such as transketolase and triosephosphate isomerase, and the osmotic stress responsive proteins like pyridoxine-4-dehydrogenase and the AKRs family. The polyols biosynthesis was really related to an osmotic response and a protection mechanism against hyperosmotic stress in Y. lipolytica. Additionally, the high osmotic stress could also induce other cell stress responses as with heat shock and oxidation stress responses, and these responsive proteins, such as the HSPs family, catalase T, and superoxide dismutase, also had drastically increased expression levels under hyperosmotic pressure.


Asunto(s)
Eritritol/metabolismo , Glicerol/metabolismo , Presión Osmótica , Proteoma/análisis , Estrés Fisiológico , Yarrowia/química , Yarrowia/fisiología , Electroforesis en Gel Bidimensional , Proteínas Fúngicas/análisis , Proteínas Fúngicas/química , Punto Isoeléctrico , Redes y Vías Metabólicas , Peso Molecular , Proteómica , Yarrowia/metabolismo
7.
Hepatogastroenterology ; 61(134): 1801-5, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25436382

RESUMEN

OBJECTIVE: To study the safety and survival outcome of surgical management for elderly gastric cancer patients. Methods: Patients proven of gastric cancer who aged ≥80 years during November 2002 to July 2011 were retrospectively analyzed. The detailed information of patients' characteristics and surgical management was retrieved. Follow-up of overall survival status was performed to analyze the surgical effectiveness. RESULTS: Totally, 92 (48 in surgery and 44 in non-surgery group) out of 187 eligible patients recorded adequate information and analyzed finally. There were 34 patients undergone radical gastrectomy, 6 palliative gastrectomy, 1 gastrojejunostomy and 7 exploratory laparotomy. Median follow-up durations were 25 (9-111) and 28 (8-114) months in surgery and non-surgery groups, respectively (p=0.797). Clinical-pathological T stage and node status were comparable. Clinical-pathological distal metastasis status was 15 and 26 M1 cases for surgery and nonsurgery, respectively (p=0.006). Incidence of postoperative complications and hospital mortality were 25.0% and 2.1%, respectively. The 2-year survival rates of M0 subgroups were 35.7% and 0% for surgery and nonesurgery, respectively (HR=3.98, p=0.022). CONCLUSIONS: The safety of surgery for well-selected ≥ 80-year elderly gastric cancer patients was potentially acceptable and the patients of early or locally advanced diseases could obtain survival benefits by surgery.


Asunto(s)
Gastrectomía , Derivación Gástrica , Neoplasias Gástricas/cirugía , Factores de Edad , Anciano de 80 o más Años , Distribución de Chi-Cuadrado , Femenino , Gastrectomía/efectos adversos , Gastrectomía/mortalidad , Derivación Gástrica/efectos adversos , Derivación Gástrica/mortalidad , Mortalidad Hospitalaria , Humanos , Estimación de Kaplan-Meier , Masculino , Complicaciones Posoperatorias/mortalidad , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Neoplasias Gástricas/mortalidad , Factores de Tiempo , Resultado del Tratamiento
8.
Bioresour Technol ; 151: 120-7, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24215768

RESUMEN

The effect of osmotic pressure on erythritol and mannitol production by an osmophilic yeast strain of Yarrowia lipolytica CICC 1675 using glycerol as the sole carbon source was investigated. Appropriately high osmotic pressure was found to enhance erythritol production and inhibit mannitol formation. A novel two-stage osmotic pressure control fed-batch strategy based on the kinetic analysis was developed for higher erythritol yield and productivity. During the first 96 h, the osmotic pressure was maintained at 4.25 osmol/kg by feeding glycerol to reduce the inhibition of cell growth. After 132 h, the osmotic pressure was controlled at 4.94 osmol/kg to maintain a high dp(ery)/dt. Maximum erythritol yield of 194.3g/L was obtained with 0.95 g/L/h productivity, which were 25.7% and 2.2%, respectively, improvement over the best results in one-stage fed-batch fermentation. This is the first report that a novel osmotic pressure control fed-batch strategy significantly enhanced erythritol production.


Asunto(s)
Técnicas de Cultivo Celular por Lotes/métodos , Eritritol/biosíntesis , Fermentación , Glicerol/metabolismo , Presión Osmótica , Yarrowia/metabolismo , Biomasa , Fermentación/efectos de los fármacos , Manitol/metabolismo , Presión Osmótica/efectos de los fármacos , Polímeros/metabolismo , Cloruro de Sodio/farmacología , Factores de Tiempo , Yarrowia/efectos de los fármacos
9.
Hepatogastroenterology ; 61(131): 853-7, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-26176086

RESUMEN

BACKGROUND/AIMS: To study the safety and survival outcome of surgical management for elderly gastric cancer patients. METHODOLOGY: Patients proven of gastric cancer who aged 80 years during November 2002 to July 2011 were retrospectively analyzed. The detailed information of patients' characteristics and surgical management was retrieved. Follow-up of overall survival status was performed to analyze the surgical effectiveness. RESULTS: Totally, 92 (48 in surgery and 44 in non-surgery group) out of 187 eligible patients recorded adequate information and analyzed finally. Median ages were 81 years in surgery group and 83 year in non-surgery group. There were 34 patients undergone radical gastrectomy, 6 palliative gastrectomy, 1 gastrojejunostomy and 7 exploratory laparotomy. Median follow-up durations were 25 (9-111) and 28 (8-114) months in surgery and non-surgery groups, respectively (p = 0.797). Clinical-pathological T stage was 6 T1, 5 T2, 14 T3 and 23 T4 cases for surgery and 7 T1, 6 T2, 3 T3, 7 T4 and 21 TX cases for non-surgery. Clinical-pathological node status was 18 N0, 7 N1, 6 N2, 7 N3 and 10 NX cases for surgery and 10 N0, 3 N1, 3 N2, 3 N3 and 25 NX cases for non-surgery. Clinical-pathological distal metastasis status was 15 and 26 M1 cases for surgery and non-surgery, respectively (p = 0.006). Incidence of postoperative complications was 25.0% and postoperative hospital mortality was 2.1%. The 2-year survival rates were 30.8% and 8.0% for surgery and none-surgery, respectively (HR = 3.023, p = 0.001), and the 3-year survival rates were 17.6% and 0% for surgery and non-surgery, respectively (HR = 3.680, p = 0.001). In M0 subgroup, 2-year survival rate was 35.7% and 0.0% for surgery and non-surgery groups, respectively (HR = 3.98, p = 0.022). CONCLUSION: The safety of surgery for well-selected ≥ 80-year elderly gastric cancer patients was potentially acceptable and the patients of early or locally advanced diseases could obtain survival benefits by surgery.


Asunto(s)
Gastrectomía , Neoplasias Gástricas/cirugía , Factores de Edad , Anciano de 80 o más Años , Femenino , Gastrectomía/efectos adversos , Gastrectomía/mortalidad , Derivación Gástrica/efectos adversos , Mortalidad Hospitalaria , Humanos , Estimación de Kaplan-Meier , Laparotomía/efectos adversos , Masculino , Estadificación de Neoplasias , Cuidados Paliativos , Selección de Paciente , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/mortalidad , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Neoplasias Gástricas/mortalidad , Neoplasias Gástricas/patología , Factores de Tiempo , Resultado del Tratamiento
10.
PLoS Biol ; 11(9): e1001655, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24058297

RESUMEN

Plant zygote divides asymmetrically into an apical cell that develops into the embryo proper and a basal cell that generates the suspensor, a vital organ functioning as a conduit of nutrients and growth factors to the embryo proper. After the suspensor has fulfilled its function, it is removed by programmed cell death (PCD) at the late stages of embryogenesis. The molecular trigger of this PCD is unknown. Here we use tobacco (Nicotiana tabacum) embryogenesis as a model system to demonstrate that the mechanism triggering suspensor PCD is based on the antagonistic action of two proteins: a protease inhibitor, cystatin NtCYS, and its target, cathepsin H-like protease NtCP14. NtCYS is expressed in the basal cell of the proembryo, where encoded cystatin binds to and inhibits NtCP14, thereby preventing precocious onset of PCD. The anti-cell death effect of NtCYS is transcriptionally regulated and is repressed at the 32-celled embryo stage, leading to increased NtCP14 activity and initiation of PCD. Silencing of NtCYS or overexpression of NtCP14 induces precocious cell death in the basal cell lineage causing embryonic arrest and seed abortion. Conversely, overexpression of NtCYS or silencing of NtCP14 leads to profound delay of suspensor PCD. Our results demonstrate that NtCYS-mediated inhibition of NtCP14 protease acts as a bipartite molecular module to control initiation of PCD in the basal cell lineage of plant embryos.


Asunto(s)
Catepsina H/metabolismo , Cistatinas/metabolismo , Nicotiana/embriología , Semillas/embriología , Secuencia de Aminoácidos , Muerte Celular , Linaje de la Célula/genética , Cistatinas/biosíntesis , Cistatinas/genética , Regulación de la Expresión Génica de las Plantas , Unión Proteica , Semillas/genética , Semillas/metabolismo , Alineación de Secuencia , Nicotiana/metabolismo
11.
Arch Med Res ; 44(3): 235-41, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23506721

RESUMEN

BACKGROUND AND AIMS: A number of studies have shown that polymorphisms in the vitamin D receptor (VDR) gene are implicated in susceptibility to type 2 diabetes (T2D). However, the results are inconsistent and inconclusive. METHODS: A meta-analysis was performed to analyze the association among the four polymorphisms (FokI, BsmI, ApaI and TaqI) in the VDR gene and T2D susceptibility. A total of 14 articles were included in this meta-analysis. RESULTS: FokI polymorphism was associated with an overall significantly increased risk of T2D (f vs. F: OR = 1.25, 95% CI = 1.10, 1.41; the extreme model ff vs. FF: OR = 1.48, 95% CI: 1.13, 1.94; the recessive model ff vs. Ff + FF: OR = 1.51, 95% CI = 1.25, 1.82). Subgroup analysis revealed a significant association between the Fok1 polymorphism and T2D in an Asian population. CONCLUSIONS: There was no between-study heterogeneity in any of these analyses. No significant associations were observed among the BsmI, ApaI and TaqI variants andT2D risk. This meta-analysis suggests that the FokI polymorphism of the VDR gene could be a risk factor for T2D, especially in an Asian population.


Asunto(s)
Pueblo Asiatico/genética , Diabetes Mellitus Tipo 2/genética , Predisposición Genética a la Enfermedad , Polimorfismo Genético , Receptores de Calcitriol/genética , Anciano , Alelos , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Sesgo de Publicación , Población Blanca/genética
12.
Asian Pac J Cancer Prev ; 14(1): 275-9, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23534737

RESUMEN

OBJECTIVES: A number of studies have shown that chronic hepatitis B virus infection is implicated in susceptibility to pancreatic cancer. However, the results are still controversial. This meta-analysis aimed to quantitatively assess the relationship between chronic hepatitis B virus infection and incidence of pancreatic cancer of cohort and case-control studies. METHODS: A literature search was performed for entries from 1990 to 2012 using PUBMED and EMBASE. Studies were included if they reported odds ratios (ORs) and corresponding 95% CIs of pancreatic cancer with respect to the infection of hepatitis B virus. RESULTS: Eight studies met the inclusion criteria, which included five case-control studies and three cohort studies. Compared with individuals who have not infection of hepatitis B virus, the pooled OR of pancreatic cancer was 1.403 (95%CI: 1.139-1.729, P=0.001) for patients with hepatitis B virus infection. Sub-group analysis by study design showed that the summary OR was 1.43 (95%CI: 1.06-1.94, P=0.021) when pooling case-control studies and 1.31 (95%CI: 1.00- 1.72, P=0.05) when pooling cohort studies. CONCLUSION: Findings from this meta-analysis suggest that chronic hepatitis B virus infection may increase the risk of pancreatic cancer. This relationship needs to be confirmed by further follow-up studies.


Asunto(s)
Hepatitis B Crónica/epidemiología , Neoplasias Pancreáticas/epidemiología , Estudios de Casos y Controles , Estudios de Cohortes , Intervalos de Confianza , Virus de la Hepatitis B , Humanos , Incidencia , Oportunidad Relativa , Neoplasias Pancreáticas/virología , Factores de Riesgo
13.
PLoS One ; 8(3): e59112, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23527102

RESUMEN

Antisense oligodeoxynucleotide (A-ODN) inhibition works well in animal cells. However, there have been few successful examples to date of its application in plants, and more specifically whether the technique can be used in pollen tubes as a model of plant cell growth. NtGNL1 plays an important role in pollen tube development and was thus selected as an indicator to assess the biological effects of A-ODN. An A-ODN inhibition technique was used to down-regulate NtGNL1 expression in tobacco pollen tubes and showed that A-ODNs could quickly enter pollen tubes through the thick wall and cell membrane and effectively block NtGNL1 expression. Phenotype analysis revealed that the down-regulation of NtGNL1 by A-ODNs resulted in abnormalities in endocytosis and subsequent vesicle trafficking, similar to the phenotypes of pollen tubes treated with NtGNL1 RNAi. This investigation confirmed that A-ODNs could specifically inhibit target gene expression, and furthermore demonstrated that A-ODN functioned in a concentration- and duration-dependent manner, because A-ODNs could be degraded when incubated with pollen tubes. Thus, the A-ODN technique was successfully used for gene function analysis in pollen tubes and appears to be an alternative and convenient technique when the in vitro pollen tube is used as the study model. This technique will greatly facilitate investigations on the molecular mechanism(s) underlying pollen tube growth.


Asunto(s)
Oligodesoxirribonucleótidos Antisentido/genética , Tubo Polínico/genética , Regulación hacia Abajo , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Oligodesoxirribonucleótidos Antisentido/metabolismo , Permeabilidad , Fenotipo , Tubo Polínico/citología , Tubo Polínico/crecimiento & desarrollo , Tubo Polínico/ultraestructura , Interferencia de ARN
14.
J Inorg Biochem ; 113: 83-93, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22709927

RESUMEN

Compared to the tetrahedral {Fe(NO)(2)}(9) dinitrosyliron complexes (DNICs) [(L)(2)Fe(NO)(2)](-) (L=SR, imidazolate) displaying EPR signal g=2.03, the newly synthesized six-/five-coordinate {Fe(NO)(2)}(9) DNICs [(TPA)Fe(NO)(2)][BF(4)] (1-TPA) (TPA=2-[CH(2)-C(5)H(4)N](3)N), [((iPr)PDI)Fe(NO)(2)][BF(4)] (2-(iPr)PDI) ((iPr)PDI=2,6-[2,6-(i)Pr(2)-C(6)H(3)N=CMe](2)C(5)H(3)N) and [(PyImiS)Fe(NO)(2)] (4-PyImiS) (PyImiS=2-[2-(C(5)H(4)N)CMe=N]C(6)H(4)S) exhibit the distinct EPR signal g=2.015-2.018. The Fe K-edge pre-edge energy (7113.4-7113.6eV) derived from the 1s→3d transition in the octahedral and square-pyramidal environment of the Fe center, falling within the range of 7113.4-7113.8eV for the tetrahedral {Fe(NO)(2)}(9) DNICs, implicates that the iron cores of DNICs 1-TPA, 2-(iPr)PDI and 4-PyImiS are tailored to minimize the electronic changes accompanying changes in coordination geometry. In contrast to the thermally stable 1-TPA, 2-(iPr)PDI and 4-PyImiS, the spontaneous transformation of the proposed thermally unstable five-coordinate {Fe(NO)(2)}(9) DNIC [(PyPepS-H)Fe(NO)(2)](-) (6-PyPepS) (PyPepS-H=[SC(6)H(4)-o-NC(O)(C(5)H(4)N)]) into the {Fe(NO)}(7)-{Fe(NO)}(7) [(µ-PyPepS-H)Fe(NO)](2) (7) along with release of nitroxyl demonstrates that the distinct electron-donating ability of the coordinated ligands ([PyPepS-H]>[PyImiS]~[TPA]>[(iPr)PDI]) regulates the stability and geometric structure of {Fe(NO)(2)}(9) DNICs. This study also shows the aspect of how the geometric structure of {Fe(NO)(2)}(9) DNICs imposed by the electron-donating ability and conformation of the coordinated ligands (tridentate [(iPr)PDI] vs tridentate [PyImiS] vs tetradentate [TPA] vs tridentate [PyPepS-H] vs bidentate [SC(6)H(4)-o-NC(O)Ph](2-)) regulates the Fe-NO bonding of {Fe(NO)(2)}(9) DNICs and presumably the release of nitroxyl from DNICs.


Asunto(s)
Complejos de Coordinación/síntesis química , Hierro/química , Óxido Nítrico/química , Óxidos de Nitrógeno/química , Complejos de Coordinación/farmacología , Cristalografía por Rayos X , Espectroscopía de Resonancia por Spin del Electrón , Electrones , Ligandos , Conformación Molecular , Temperatura , Termodinámica
15.
Eur J Endocrinol ; 167(1): 75-84, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22535645

RESUMEN

OBJECTIVES: Whether subclinical hyperthyroidism (SCH) results in poor prognosis remains controversial. Our aim was to evaluate the association between SCH and the risk of cardiovascular disease (CVD), cardiovascular mortality, and all-cause mortality by conducting a meta-analysis of cohort studies. METHODS: The PubMed and Embase databases were searched through November 2011 to identify studies that met pre-stated inclusion criteria. Relevant information for analysis was extracted. Either a fixed or a random effects model was used to calculate the overall combined risk estimates. RESULTS: Seventeen cohort studies were included in this meta-analysis. The overall combined relative risks for individuals with SCH compared with the reference group were 1.19 (95% confidence interval (CI): 1.10 to 1.28) for CVD, 1.52 (95% CI: 1.08 to 2.13) for cardiovascular mortality, and 1.25 (95% CI: 1.00 to 1.55) for all-cause mortality. Subgroup analysis by sample source (community or convenience sample) showed that the significant association for cardiovascular and all-cause mortality only existed when pooling studies from convenience samples. Heterogeneity was observed when pooling studies on the association between SCH and cardiovascular and all-cause mortality. Sensitivity analysis showed omission of each individual study did not significantly change the pooled effects. No evidence of publication bias was observed. CONCLUSIONS: Our findings demonstrated that SCH significantly increased the risk of CVD for the general population and the risk of cardiovascular and all-cause mortality for the individuals with other morbidities.


Asunto(s)
Enfermedades Cardiovasculares/etiología , Hipertiroidismo/complicaciones , Hipertiroidismo/mortalidad , Enfermedades Cardiovasculares/mortalidad , Humanos , Modelos Teóricos , Riesgo , Índice de Severidad de la Enfermedad
16.
PLoS One ; 5(10): e13401, 2010 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-20976165

RESUMEN

BACKGROUND: Tobacco GNOM LIKE 1 (NtGNL1), a new member of the Big/GBF family, is characterized by a sec 7 domain. Thus, we proposed that NtGNL1 may function in regulating pollen tube growth for vesicle trafficking. METHODOLOGY/PRINCIPAL FINDINGS: To test this hypothesis, we used an RNAi technique to down-regulate NtGNL1 expression and found that pollen tube growth and orientation were clearly inhibited. Cytological observations revealed that both timing and behavior of endocytosis was disrupted, and endosome trafficking to prevacuolar compartments (PVC) or multivesicular bodies (MVB) was altered in pollen tube tips. Moreover, NtGNL1 seemed to partially overlap with Golgi bodies, but clearly colocalized with putative late endosome compartments. We also observed that in such pollen tubes, the Golgi apparatus disassembled and fused with the endoplasmic reticulum, indicating abnormal post-Golgi trafficking. During this process, actin organization was also remodeled. CONCLUSIONS/SIGNIFICANCE: Thus, we revealed that NtGNL1 is essential for pollen tube growth and orientation and it likely functions via stabilizing the structure of the Golgi apparatus and ensuring post-Golgi trafficking.


Asunto(s)
Endocitosis/fisiología , Aparato de Golgi/metabolismo , Nicotiana/crecimiento & desarrollo , Proteínas de Plantas/fisiología , Polen , Actinas/metabolismo , Citoesqueleto/metabolismo , Regulación hacia Abajo , Proteínas de Plantas/genética , Plantas Modificadas Genéticamente , Interferencia de ARN , Nicotiana/genética , Nicotiana/metabolismo
17.
Inorg Chem ; 44(9): 3226-32, 2005 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-15847431

RESUMEN

Reaction of Fe(CO)2(NO)2 and [(ON)Fe(S,S-C6H3R)2]- (R = H (1), CH3 (1-Me))/[(ON)Fe(SO2,S-C6H4)(S,S-C6H4)]- (4) in THF afforded the diiron thiolate/sulfinate nitrosyl complexes [(ON)Fe(S,S-C6H3R)2 Fe(NO)2]- (R = H (2), CH3 (2-Me)) and [(ON)Fe(S,SO2-C6H4)(S,S-C6H4)Fe(NO)2]- (3), respectively. The average N-O bond lengths ([Fe(NO)2] unit) of 1.167(3) and 1.162(4) A in complexes 2 and 3 are consistent with the average N-O bond length of 1.165 A observed in the other structurally characterized dinitrosyl iron complexes with an {Fe(NO)2}9 core. The lower nu(15NO) value (1682 cm(-1) (KBr)) of the [(15NO)FeS4] fragment of [(15NO)Fe(S,S-C6H3CH3)2 Fe(NO)2]- (2-Me-15N), compared to that of [(15NO)Fe(S,S-C6H3CH3)2]- (1-Me-15N) (1727 cm(-1) (KBr)), implicates the electron transfer from {Fe(NO)2}10 Fe(CO)2(NO)2 to complex 1-Me/1 may occur in the process of formation of complex 2-Me/2. Then, the electronic structures of the [(NO)FeS4] and [S2Fe(NO)2] cores of complexes 2, 2-Me, and 3 were best assigned according to the Feltham-Enemark notation as the {Fe(NO)}7-{Fe(NO)2}9 coupling (antiferromagnetic interaction with a J value of -182 cm(-1) for complex 2) to account for the absence of paramagnetism (SQUID) and the EPR signal. On the basis of Fe-N(O) and N-O bond distances, the dinitrosyliron {L2Fe(NO)2} derivatives having an Fe-N(O) distance of approximately 1.670 A and a N-O distance of approximately 1.165 A are best assigned as {Fe(NO)2}9 electronic structures, whereas the Fe-N(O) distance of approximately 1.650 A and N-O distance of approximately 1.190 A probably imply an {Fe(NO)2}10 electronic structure.

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