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1.
Environ Sci Process Impacts ; 24(4): 598-608, 2022 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-35332912

RESUMEN

Dissolved solids released from biochar (DSRB), including organic and inorganic compounds, may affect the role of biochar as a soil amendment. In this study, the effects of DSRB on soil microbe metabolism, especially CO2 fixation, were evaluated in liquid soil extract. DSRB were found to be released in large amounts (289.05 mg L-1 at 1 hour) from biochar over a short period of time before their rate of release slowed to a gradual pace. They increased the microbial biomass and provided energy and reducing power to microbes, while reducing their metabolic output of extracellular proteins and polysaccharides. DSRB inputs led to the redistribution of metabolic flux in soil microorganisms and an increased organic carbon content in the short term. This content gradually decreased as it was utilized. DSRB did not improve microbial CO2 fixation but, rather, enhanced its release, while promoting specific soil microorganism genera, including Cupriavidus, Flavisolibacter, and Pseudoxanthomonas. These heterotrophic genera may compete with autotrophic microorganisms for nutrients but have positive synergistic relationships with autotrophs during CO2 fixation. These results demonstrated that reducing the DSRB in biochar can improve its role as a soil amendment by enhancing soil carbon storage and CO2 fixation capabilities.


Asunto(s)
Microbiología del Suelo , Suelo , Carbono , Dióxido de Carbono/análisis , Carbón Orgánico
2.
J Agric Food Chem ; 68(21): 5863-5872, 2020 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-32375483

RESUMEN

In this study, the effect of soluble polysaccharides (SPs) derived from agricultural waste, rice straw, on fermentation-associated stresses (temperature and concentrations of glucose and ethanol) was investigated to achieve high-performance ethanol production. The increase in temperature and concentrations of glucose and ethanol significantly inhibited Saccharomyces cerevisiae growth and lowered ethanol fermentation efficiency. Flow cytometric assays indicated that SPs could alleviate membrane permeability damage caused by fermentation-associated stresses. Atomic force microscopy and transmission electron microscopy revealed that fermentation-associated stresses induced cell surface shrinkage, causing a decrease in the cell size, whereas SPs stimulated the formation of extracellular matrices (EMs), which made the cell surface smooth and the cell morphology regular. Cells with EMs induced by SPs could efficiently produce ethanol under severe stresses. As a result, the titer of ethanol in the fermentation with SPs was 1.40-fold (from 26.40 to 36.98 g/L) higher than that in the fermentation without SPs, suggesting the stress-alleviating effect of SPs on ethanol production.


Asunto(s)
Etanol/metabolismo , Saccharomyces cerevisiae/metabolismo , Biocombustibles/análisis , Fermentación , Glucosa/metabolismo , Oryza/metabolismo , Oryza/microbiología , Tallos de la Planta/metabolismo , Tallos de la Planta/microbiología , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crecimiento & desarrollo , Residuos/análisis
3.
Medicine (Baltimore) ; 97(39): e12580, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30278567

RESUMEN

Apelin, the ligand for the APJ receptor, is involved in the pathogenesis of atrial fibrillation (AF). However, whether serum apelin can predict the recurrence of AF after pulmonary vein isolation (PVI) has not been determined.A prospective cohort study was performed in patients with AF (but without structural heart disease) who were undergoing first-time PVI. Serum apelin-12 was measured by enzyme-linked immunosorbent assay. Echocardiographic examination was performed at baseline, 3 months, and 6 months after PVI. Patients were followed up for 6 months after PVI, and the association between baseline apelin-12 and AF recurrence (early recurrence: within 3 months after ablation; late recurrence: 3-6 months after ablation) was analyzed.A total of 61 patients were included in the study. Baseline serum level of apelin-12 was significant lower in patients with early (median [interquartile range]: 1844 [1607-2061] vs 2197 [1895-2455] ng/L, P = .01) and late (1639 [1524-1853] vs 1923 [1741-2303] ng/L, P = .02) AF recurrence compared with patients without these events. Results of Cox stepwise multivariate analysis demonstrated that lower baseline apelin-12 (<2265 ng/L) was independently associated with increased AF recurrence within 6 months after PVI (P < .05). The specificity and positive predictive value of apelin-12 for AF recurrence were significantly higher than those of baseline N-terminal brain proBNP (60.4% vs 28.6%, P < .001; 58.8% vs 34.4%, P = .01), although the sensitivity and negative predictive value were similar.Reduced baseline serum apelin-12 may be an independent risk factor for the recurrence of AF after PVI in patients without structural heart disease.


Asunto(s)
Apelina/sangre , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/cirugía , Ablación por Catéter/métodos , Venas Pulmonares/cirugía , Adulto , Anciano , Fibrilación Atrial/sangre , Fibrilación Atrial/diagnóstico por imagen , Ecocardiografía , Ensayo de Inmunoadsorción Enzimática , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Estudios Prospectivos , Recurrencia
4.
Oncotarget ; 7(13): 16996-7008, 2016 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-26959738

RESUMEN

In vivo and in vitro studies have indicated the link of cholesterol consumption and endometrial cancer risk, however, previous observational studies have yielded inconsistent results. Additionally, a previous meta-analysis published in 2007 found limited evidence of aforementioned association. Therefore, we performed the dose-response meta-analysis to address this concern. Studies were identified using the PubMed, EMBASE and Web of Science databases from the database inception to the end of June 2015 as well as by examining the references of retrieved articles. Two authors independently performed the eligibility evaluation and data extraction. The summary risk estimates and 95% confidence intervals (CIs) were summarized by the random-effects models. One cohort and nine case-control studies were included in the dose-response analyses. Risk of endometrial cancer increased by 6% for 100 mg/day increment in the dietary consumption of cholesterol (Odds ratio (OR) = 1.06; 95% CI = 1.00-1.12), with significant heterogeneity (I2 = 64.2, P = 0.003). When stratified by study design, the result was significant in case-control studies (OR = 1.07; 95% CI = 1.01-1.13). Additionally, although the direction of the associations were consistent in the subgroup analyses stratified by study characteristics and adjustment for potential confounders, not all of them showed statistical significance. In summary, findings of the present dose-response meta-analysis partly support the positive association between dietary cholesterol consumption and risk of endometrial cancer. Since only one cohort study was included, more prospective studies and pooled analysis of observational studies are warranted to confirm our findings in the future.


Asunto(s)
Colesterol en la Dieta/efectos adversos , Neoplasias Endometriales/epidemiología , Femenino , Humanos , Estudios Observacionales como Asunto
5.
Oncotarget ; 6(34): 36081-97, 2015 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-26462150

RESUMEN

Epidemiological studies have provided controversial evidence of the association between dietary fatty acids intake and endometrial cancer risk. The continuous update project of World Cancer Research Fund failed to focus on this issue. To address this inconsistency, we conducted this dose-response meta-analysis based on epidemiological studies published up to the end of June 2015 identified from PubMed, EMBASE and Web of Science. Two authors independently performed the eligibility evaluation and data extraction. Random-effects models were used to estimate summary relative risks (RRs) and 95% confidence intervals (CIs). Fourteen epidemiological studies (4 cohort and 10 case-control studies) were included in this dose-response meta-analysis. The summary RR for an intake increment of 10g/day was 1.02 (95% CI = 0.97-1.08; I2 = 66.0%) for saturated fatty acids, 0.98 (95% CI = 0.96-1.001; I2 = 0%) for monounsaturated fatty acids, and 1.00 (95% CI = 0.95-1.06; I2 = 0%) for polyunsaturated fatty acids intake. Non-significant results were observed in the majority of subgroup analyses stratified by study characteristics and adjustment for potential confounders in analyses of aforementioned associations. In conclusion, results from this dose-response meta-analysis provided limited evidence that dietary saturated, monounsaturated, and polyunsaturated fatty acids consumption was associated with endometrial cancer risk. Further studies, especial prospective designed or pooled studies are warranted to confirm our findings.


Asunto(s)
Neoplasias Endometriales/epidemiología , Ácidos Grasos/administración & dosificación , Estudios de Cohortes , Dieta/estadística & datos numéricos , Relación Dosis-Respuesta a Droga , Neoplasias Endometriales/etiología , Femenino , Humanos , Factores de Riesgo
6.
Cancer Causes Control ; 26(9): 1307-14, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26156047

RESUMEN

PURPOSE: The relationship between fish consumption and multiple myeloma (MM) risk has not been consistent across epidemiological studies. We quantitatively assessed the aforementioned association through a systematic review and meta-analysis. METHODS: PubMed was searched through the end of March 2015 for eligible studies. Fixed or random effects models were used to pool risk estimates. Five case-control studies that involved 1,366 cases and 8,259 controls were identified. Three studies had high methodological quality, and two studies had low quality based on the Newcastle-Ottawa Quality Assessment Scale. RESULTS: After pooling all risk estimates, a significant inverse association was found between the highest category versus lowest category of fish consumption and MM risk (relative risk = 0.65, 95% confidence interval = 0.46-0.91), with relatively high heterogeneity (I(2) = 55.6%). No evidence of publication bias was detected. The inverse association persisted in all subgroups according to study quality, type, location, and whether there were adjustments for confounders, although statistical significance was not detected in all strata. The dose-response analysis suggested a nonlinear dose-response relationship for the association, with the lowest risk linked to fish consumption once per week. CONCLUSION: This meta-analysis suggests that the highest versus lowest category of fish consumption is inversely associated with MM risk. Furthermore, a nonlinear dose-response relationship was suggested for the association. Because this evidence is based on a small number of retrospective studies with mixed quality and because high heterogeneity was detected, further prospective studies are warranted to validate our findings and better characterize the relationship.


Asunto(s)
Dieta/efectos adversos , Peces , Mieloma Múltiple/etiología , Alimentos Marinos , Animales , Estudios de Casos y Controles , Humanos , Mieloma Múltiple/epidemiología , Estudios Prospectivos , Estudios Retrospectivos , Riesgo
7.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 22(1): 30-4, 2014 Feb.
Artículo en Chino | MEDLINE | ID: mdl-24598646

RESUMEN

This study was purpose to investigate the expression of death-associated protein kinase (DAPK) gene in acute leukemia (AL) patients and the methylation status of its promoter region through experiments of DAPK methylation and expression, and to analyze the relation between them. The expression of DAPK gene in leukemia cells and normal bone marrow cells was detected by RT-PCR; the methylation status of DAPK gene promoter region in cells from AL patients and leukemia cell lines HL-60 and U937 was detected by nested methylation specific PCR (n-MSP); 2 randomly primers selected from randomly amplified products of second round nMS-PCR were cloned and sequenced in professional company. The results showed that the DAPK gene expressed in bone marrow specimens of all 10 normal controls, with average value of expression 0.92 ± 0.18, while the average value of DAPK expression in bone marrow specimens of AL patients was 0.61 ± 0.40 which was lower than that in normal controls (P < 0.05). The low or deletion of DAPK mRNA expression were found in bone marrow specimens of 9/17 (52.94%) cases of ALL and 42/102 (41.18%) cases of AML. The cell line U937 showed normal expression of DAPK gene, while cell line HL-60 showed the expression detection of DAPK gene. The methylation of DAPK promoter region existed in 33 out of bone marrow specimens of 102 AML patients and in 8 out of bone marrow specimens of 17 ALL patients, the methylation rates were 32.4% (33/102) and 47% respectively. The DAPK promoter region in bone marrow of 7 normal controls was unmethylated, while DAPK promoter region in U937 cells and HL-60 cells were unmethylated and methylated respectively. The DAPK mRNA expression in ALL and AML patients significantly negatively correlated with the methylation of its promoter region (r = -0.855, P < 0.05, in AML patients and r = -0.343, P < 0.05, in AML patients) suggesting the close relationship between them. It is concluded that the methylation of DAPK gene promoter region relates with abnormal expression or detection of DAPK mRNA in AL patients.


Asunto(s)
Metilación de ADN , Proteínas Quinasas Asociadas a Muerte Celular/genética , Leucemia/genética , Regiones Promotoras Genéticas , Enfermedad Aguda , Estudios de Casos y Controles , Células HL-60 , Humanos , ARN Mensajero/genética
8.
Zhong Yao Cai ; 33(12): 1841-4, 2010 Dec.
Artículo en Chino | MEDLINE | ID: mdl-21548356

RESUMEN

OBJECTIVE: A molecular biology method was studied to identify medical Dendrobium and to provide a method for quality control of these plants. METHOD: ISSR primer was screened through ISSR-PCR reaction according to its gene resolving power, and digital barcodes were established for identification. RESULTS: Screening 2 primers which Rp value above 8, This primers can identify medical Dendrobium from 6 kinds 8 groups. CONCLUSION: ISSR molecular maker technology is useful for identifying species and habitats of medical Dendrobium plants.


Asunto(s)
ADN de Plantas/genética , Dendrobium/clasificación , Dendrobium/genética , Plantas Medicinales/genética , Secuencias Repetitivas de Ácidos Nucleicos , Dermatoglifia del ADN , Cartilla de ADN , Marcadores Genéticos , Genética de Población , Filogenia , Hojas de la Planta/genética , Plantas Medicinales/clasificación , Reacción en Cadena de la Polimerasa , Polimorfismo Genético , Especificidad de la Especie
9.
Acta Pharmacol Sin ; 29(2): 169-76, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18215345

RESUMEN

AIM: Stem cells hold great promise for brain and spinal cord injuries (SCI), but cell survival following transplantation to adult central nervous system has been poor. Salvianolic acid B (Sal B) has been shown to improve functional recovery in brain-injured rats. The present study was designed to determine whether Sal B could improve transplanted mesenchymal stem cell (MSC) survival in SCI rats. METHODS: SCI rats were treated with Sal B. The Basso-Beatie-Bresnahan (BBB) scale was used to test the functional recovery. Sal B was used to protect MSC from being damaged by TNF-alpha in vitro. Bromodeoxyuridine-labeled MSC were transplanted into SCI rats with Sal B intraperitoneal injection, simultaneously. MSC were examined, and the functional recovery of the SCI rats was tested. RESULTS: Sal B treatment significantly reduced the lesion area from 0.26+/-0.05 mm2 to 0.15+/-0.03 mm2 (P<0.01) and remarkably raised the BBB scores on d 28, post-injury, from 7.3+/-0.9 to 10.5+/-1.3 (P<0.05), compared with the phosphate-buffered saline (PBS) control group. MSC were protected from the damage of TNF-alpha by Sal B. The number of surviving MSC in the MSC plus Sal B groups were 1143.3+/-195.6 and 764.0+/-81.3 on d 7 and 28, post-transplantation, more than those in the MSC group, which was 569.3+/-72.3 and 237.0+/-61.3, respectively (P<0.05). Rats with MSC transplanted and Sal B injected obtained higher BBB scores than those with MSC transplanted alone (P<0.05) and PBS (P<0.01). CONCLUSION: Sal B provides neuroprotection to SCI and promotes the survival of MSC in vitro and after cell transplantation to the injured spinal cord in vivo.


Asunto(s)
Antioxidantes/farmacología , Benzofuranos/farmacología , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/efectos de los fármacos , Traumatismos de la Médula Espinal/terapia , Animales , Conducta Animal/fisiología , Supervivencia Celular/efectos de los fármacos , Masculino , Ratas , Ratas Sprague-Dawley , Traumatismos de la Médula Espinal/psicología , Factor de Necrosis Tumoral alfa/farmacología
10.
Zhonghua Yi Xue Za Zhi ; 84(17): 1475-7, 2004 Sep 02.
Artículo en Chino | MEDLINE | ID: mdl-15500749

RESUMEN

OBJECTIVE: To observe the effect of radiation on the expression of smooth muscle actin (SMA) in the bile duct during the healing process and the inhibitory function of (103)palladium (Pd) radioactive stent on the stricture of bile duct after injury. METHODS: Twelve mongrel dogs were made models of bile duct injury: duodenotomy was performed, a balloon catheter was inserted into the general bile duct and saline with high pressure was perfused thereinto to cause laceration of the mucosa, and then the balloon catheter was withdrawn and ordinary alloy stent or (103)Pd radioactive stent was inserted into the general bile duct. Thirty days after the dogs were killed. Their bile ducts were taken out to undergo HE staining to observe the area of general bile duct, thickness of the tunica intima, area of residual bile duct cavity, stricture degree, and circumference of bile duct. The expression of SMA in the bile duct tissue was detected by immunoistochemistry. RESULTS: SMA was expressed in 5 of the 6 specimens of bile duct in the (103)Pd radioactive stent group and 2 of the 6 specimens of the ordinary stent group (P < 0.01). The maximum thickness of tunica intima of general bile duct was 0.78 mm +/- 0.12 mm in the (103)Pd radioactive stent group, significantly less than that of the ordinary stent group (1.86 mm +/- 0.14 mm, P < 0.01). The percentage of maximum stricture area of the (103)Pd radioactive stent group was 23% +/- 16%, significantly lower that that of the ordinary stent group (56% +/- 22%, P < 0.01). The circumference of bile duct cavity of the (103)Pd radioactive stent group was 9.7 mm +/- 1.6 mm, significantly longer that of the ordinary stent group (7.0 mm +/- 1.4 mm, P < 0.01). CONCLUSION: (103)Pd radioactive stent reduces the expression of SMA in the bile duct during the healing process, thus inhibiting the stricture of bile duct caused by scar contracture at the anastomotic stoma.


Asunto(s)
Actinas/biosíntesis , Conductos Biliares/efectos de la radiación , Paladio/administración & dosificación , Radioisótopos/administración & dosificación , Stents , Actinas/genética , Animales , Conductos Biliares/metabolismo , Conductos Biliares/patología , Constricción Patológica/prevención & control , Constricción Patológica/terapia , Perros , Masculino , Músculo Liso/efectos de la radiación , Cicatrización de Heridas/efectos de la radiación
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