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2.
World J Diabetes ; 14(9): 1412-1421, 2023 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-37771333

RESUMEN

BACKGROUND: Early diabetic nephropathy (DN) is a complication of diabetes mellitus. It mainly affects kidney microvessels and glomerular function, and its timely and effective treatment is critical for early DN. However, the effects of treatments comprising simple Western medicine are not optimal. With the promotion and implementation of integrated Chinese and western medicine treatments, remarkable results have been achieved for many diseases. To this end, we explored the clinical efficacy of integrated traditional Chinese and western medicines for the treatment of early DN. AIM: To investigate the effect of sitagliptin tablets combined with Yiqi yangyin huoxue decoction on clinical efficacy and hemorheology in patients with early DN. METHODS: Through a retrospective analysis, 123 patients with early DN were admitted to the endocrinology clinic of the Changzhou NO. 7 People's Hospital from January 2021 to October 2022 and were selected as study subjects. After rigorous screening, 100 patients with early DN were enrolled. The control group (CG, n = 50) and the observation group (OG, n = 50) were divided according to the treatment method. The CG were treated with sitagliptin, and the OG were treated with sitagliptin plus the Yiqi yangyin huoxue decoction. Both groups were treated for 3 mo. For both groups, the baseline data and clinical efficacy were compared, and changes in blood glucose levels, lipid levels, renal function, and hematological indicators before (T0) and after (T1) treatment were assessed. RESULTS: The total effective rate for the OG was 94.00% and that of the CG was 80.00% (P < 0.05). After treatment (T1), the levels of fasting blood glucose, 2 h postprandial glucose, total cholesterol, triacylglycerol, and low-density lipoprotein cholesterol in OG patients were obviously lower than those in the CG (P < 0.05), and cystatin C, homocysteine, urinary microalbumin, and blood creatinine values in OG patients were also obviously lower than those in the CG (P < 0.05); erythrocyte deposition, plasma viscosity, whole blood high shear viscosity, and whole blood low shear viscosity were markedly lower in OG patients than in the CG (P < 0.05). CONCLUSION: Sitagliptin combined with Yiqi yangyin huoxue decoction has a remarkable effect when used to treat patients with early DN. Further, it is helpful in improving hemorheological indices and controlling disease progression.

3.
BMC Infect Dis ; 23(1): 364, 2023 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-37254061

RESUMEN

AIM: Until now, the performance of interferon-γ release assay (IGRA) and Mantoux tests remains unclear in infant tuberculous meningitis (TBM). Therefore, a systematic review is performed to evaluate the sensitivity of IGRA and Mantoux tests for the diagnosis of infant TBM in low and intermediate tuberculosis (TB) burden countries, while following PRISMA. METHODS: Several databases, including PubMed, EBSCO, Embase, Scopus, Web of Science, ClinicalTrials.gov, and Cochrane Central Register of Controlled Trials, were searched. Articles describing the results of IGRA or Mantoux tests among infant TBM were included for analysis. Data, such as age, sex, Mantoux test or IGRA, and cerebrospinal fluid (CSF) microbiological examinations (such as acid-fast bacilli (AFB) smear, TB PCR, and TB culture), were extracted from each study. RESULTS: A total of 31 articles were enrolled for further analysis, including 48 cases. The mean age was 9.4 ± 5.8 months and boys accounted for 57.1% of infants (24/42). Mantoux test was positive in 57.4% (27/47) of tested infants and IGRA was positive in 77.8% (7/9) of infants. In addition, among the infants with confirmed TB, 18 (52.9%, 18/34) of them have positive Mantoux responses and 7 (20.0%, 7/35) have positive IGRA results. CONCLUSIONS: In low or intermediate TB burden countries, the Mantoux test has a poor performance for diagnosing TBM among infants, and IGRAs appear to have a moderate sensitivity for the diagnosis of infant TBM.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis Meníngea , Humanos , Lactante , Masculino , Interferón gamma/análisis , Ensayos de Liberación de Interferón gamma/métodos , Sensibilidad y Especificidad , Prueba de Tuberculina , Tuberculosis Meníngea/diagnóstico , Tuberculosis Meníngea/líquido cefalorraquídeo , Femenino
4.
Inflammation ; 45(6): 2388-2405, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35776290

RESUMEN

Enteric glial cells (EGCs) are involved in intestinal inflammation. In this study, we will investigate how Bifidobacterium bifidum (B.b.) and Bacteroides fragilis (B.f.) influence EGC regulation. After pretreatment with lipopolysaccharide (LPS) and interferon-γ (IFN-γ), the expressions of major histocompatibility complex class II (MHC-II), CD80, CD86, glial cell line-derived neurotrophic factor (GDNF), toll-like receptor 2 (TLR-2), and tumor necrosis factor-α (TNF-α) in EGCs were detected using polymerase chain reaction and western blot after co-culture with the supernatants of B.b. or B.f. (multiplicity of infection, 40:1 or 80:1). Finally, EGCs were co-cultured with naive CD4+ T cells, and the expressions of interleukin (IL)-2, IL-4, IL-10, and IL-17 in supernatant were measured using enzyme-linked immunosorbent assay (ELISA). The mRNA expressions of MHC-II and CD86 in EGCs were increased after combined stimulation with LPS and IFN-γ. The expressions of MHC-II, GDNF, TLR-2, and TNF-α were all significantly upregulated in stimulated EGCs. The B.b. supernatant downregulated the expressions of MHC-II, GDNF, TLR-2, and TNF-α in stimulated EGCs, whereas the B.f. supernatant upregulated TLR-2 expression and downregulated MHC-II expression. The expressions of IL-4, IL-2, and IL-17 after co-culture of naive CD4+ T cells and stimulated EGCs were significantly increased. The supernatant of B.b. or B.f. downregulated the expressions of these cytokines. The low-concentration B.b. supernatant upregulated IL-10 expression. Conclusions B.b. and B.f. may influence intestinal inflammation by regulating MHC-II, GDNF, TLR-2, and TNF-α expression in EGCs and IL-4, IL-2, IL-17, and IL-10 secretion.


Asunto(s)
Bacteroides fragilis , Bifidobacterium bifidum , Neuroglía , Humanos , Bacteroides fragilis/metabolismo , Bifidobacterium bifidum/metabolismo , Células Cultivadas , Factor Neurotrófico Derivado de la Línea Celular Glial/metabolismo , Inflamación/metabolismo , Interferón gamma/metabolismo , Interleucina-10/metabolismo , Interleucina-17/metabolismo , Interleucina-2 , Interleucina-4/metabolismo , Lipopolisacáridos , Neuroglía/metabolismo , Neuroglía/microbiología , Receptor Toll-Like 2/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo
5.
Genes Environ ; 43(1): 56, 2021 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-34903302

RESUMEN

BACKGROUND: The microbial ecosystem in the human gut varies between individuals with differences in diet. Selenium is one of most common trace elements in everyday diet, and selenium intake affects the human gut microbiota. We studied the effect of selenium intake on the gut microbiota in regions of Enshi with different distributions of selenium. METHODS: One hundred elderly subjects (>65 years) were recruited from high-selenium and low-selenium areas in Enshi and blood, nail, and fecal specimens were obtained. The selenium contents in these samples were determined in triplicate by hydride generation atomic fluorescence spectrometry. DNA was extracted from fecal specimens and the microbial diversity was analyzed by 16 S RNA. RESULTS: The selenium contents in the blood and nails were significantly different between the high- and low-selenium areas, and the composition of the intestinal microbiota, including abundance and extent of intestinal flora, was altered. The function and metabolic pathways of the gut microbiota showed clear differences. CONCLUSIONS: As a trace element in human diet, selenium intake is an important factor that affects the intestinal microbiota and is likely involved in many human diseases. This study provides new clues and ideas for studying the correlation between selenium and human health.

6.
Aging (Albany NY) ; 13(8): 11629-11645, 2021 04 20.
Artículo en Inglés | MEDLINE | ID: mdl-33879631

RESUMEN

Emerging evidence has demonstrated that circular RNAs (circRNAs) are abnormally expressed in non-small cell lung carcinoma (NSCLC). However, the contributions of circRNAs to the tumorigenesis of lung adenocarcinoma (LUAD), one of the subtypes of NSCLC, remain unclear. Based on a microarray assay, we found that hsa_circ_0072309 was significantly upregulated in NSCLC compared with matched normal samples. Moreover, functional experiments demonstrated that hsa_circ_0072309 promotes the proliferation, migration, and invasion of NSCLC cells. In vitro precipitation of circRNAs, luciferase reporter assays, and biotin-coupled microRNA capture assays were carried out to investigate the mechanisms by which hsa_circ_0072309 regulates NSCLC. Through the above work, we found that hsa_circ_0072309 interacted with miR-607 via its miRNA response element to upregulate the expression of FTO, an m6A demethylase and downstream target of miR-607, thus promoting tumorigenesis of NSCLC. In total, our findings indicated the oncogenic role of hsa_circ_0072309 in NSCLC and provide a potential target for treatment.


Asunto(s)
Dioxigenasa FTO Dependiente de Alfa-Cetoglutarato/genética , Carcinoma de Pulmón de Células no Pequeñas/genética , Neoplasias Pulmonares/genética , MicroARNs/metabolismo , ARN Circular/metabolismo , Animales , Carcinogénesis/efectos de los fármacos , Carcinogénesis/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Movimiento Celular/genética , Proliferación Celular/efectos de los fármacos , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , Técnicas de Silenciamiento del Gen , Humanos , Pulmón/patología , Neoplasias Pulmonares/patología , Ratones , MicroARNs/antagonistas & inhibidores , Invasividad Neoplásica/genética , ARN Circular/genética , Regulación hacia Arriba , Ensayos Antitumor por Modelo de Xenoinjerto
7.
Plant Cell Rep ; 40(2): 361-374, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33392730

RESUMEN

KEY MESSAGE: MANNANASE7 gene in Brassica napus L. encodes a hemicellulose which located at cell wall or extracellular space and dehiscence-resistance can be manipulated by altering the expression of MANNANASE7. Silique dehiscence is an important physiological process in plant reproductive development, but causes heavy yield loss in crops. The lack of dehiscence-resistant germplasm limits the application of mechanized harvesting and greatly restricts the rapeseed (Brassica napus L.) production. Hemicellulases, together with cellulases and pectinases, play important roles in fruit development and maturation. The hemicellulase gene MANNANASE7 (MAN7) was previously shown to be involved in the development and dehiscence of Arabidopsis (Arabidopsis thaliana) siliques. Here, we cloned BnaA07g12590D (BnMAN7A07), an AtMAN7 homolog from rapeseed, and demonstrate its function in the dehiscence of rapeseed siliques. We found that BnMAN7A07 was expressed in both vegetative and reproductive organs and significantly highly expressed in leaves, flowers and siliques where the abscission or dehiscence process occurs. Subcellular localization experiment showed that BnMAN7A07 was localized in the cell wall. The biological activity of the BnMAN7A07 protein isolated and purified through prokaryotic expression system was verified to catalyse the decomposition of xylan into xylose. Phenotypic studies of RNA interference (RNAi) lines revealed that down-regulation of BnMAN7A07 in rapeseed could significantly enhance silique dehiscence-resistance. In addition, the expression of upstream silique development regulators is altered in BnMAN7A07-RNAi plants, suggesting that a possible feedback regulation mechanism exists in the regulation network of silique dehiscence. Our results demonstrate that dehiscence-resistance can be manipulated by altering the expression of hemicellulase gene BnMAN7A07, which could provide an available genetic resource for breeding practice in rapeseed which is beneficial to mechanized harvest.


Asunto(s)
Brassica napus/enzimología , Glicósido Hidrolasas/metabolismo , Polisacáridos/metabolismo , Arabidopsis/enzimología , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Brassica napus/genética , Pared Celular/enzimología , Regulación hacia Abajo , Espacio Extracelular/enzimología , Flores/enzimología , Flores/genética , Regulación de la Expresión Génica de las Plantas , Glicósido Hidrolasas/genética , Manosidasas/genética , Manosidasas/metabolismo , Fitomejoramiento , Hojas de la Planta/enzimología , Hojas de la Planta/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
8.
Chin J Nat Med ; 18(12): 890-897, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33357719

RESUMEN

Paclitaxel, a tetracyclic diterpenoid compounds, was firstly isolated from the bark of the Pacific yew trees. Currently, as a low toxicity, high efficiency, and broad-spectrum natural anti-cancer drug, paclitaxel has been widely used against ovarian cancer, breast cancer, uterine cancer, and other cancers. As the matter of fact, natural paclitaxel from Taxus species has been proved to be environmentally unsustainable and economically unfeasible. For this reason, researchers from all over the world are devoted to searching for new ways of obtaining paclitaxel. At present, other methods, including artificial cultivation of Taxus plants, microbial fermentation, chemical synthesis, tissue and cell culture have been sought and developed subsequently. Meanwhile, the biosynthesis of paclitaxel is also an extremely attractive method. Unlike other anti-cancer drugs, paclitaxel has its unique anti-cancer mechanisms. Here, the source, production, and anti-cancer mechanisms of paclitaxel were summarized and reviewed, which can provide theoretical basis and reference for further research on the production, anti-cancer mechanisms and utilization of paclitaxel.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Neoplasias/tratamiento farmacológico , Paclitaxel/farmacología , Antineoplásicos Fitogénicos/biosíntesis , Antineoplásicos Fitogénicos/aislamiento & purificación , Humanos , Paclitaxel/biosíntesis , Paclitaxel/aislamiento & purificación
10.
Inflammation ; 43(6): 2166-2177, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32638263

RESUMEN

Enteric glial cells (EGCs) and enteric glial-derived neurotrophic factor (GDNF) are directly involved in intestinal inflammation. In this study, we sought to examine the possible mechanisms for how Bifidobacterium bifidum (B.b.) and Bacteroides fragilis (B.f.) influence EGC regulation. In this study, lipopolysaccharide (LPS) and interferon-γ (IFN-γ) were used as exogenous stimuli of EGCs to establish an intestinal inflammation model. After stimulation with LPS and IFN-γ, B.b. and B.f. supernatants were used to activate EGCs and to examine EGC immune mechanisms. For this purpose, qRT-PCR, western blotting, and laser scanning confocal microscopy (LSCM) were used to detect the expression of NLRP3, NLRP6, NGF, NT-3, IL-18, IL-1ß, and caspase-1. We found that EGCs, after stimulation with LPS and IFN-γ, could express NLRP3, NLRP6, NT-3, NGF, IL-18, IL-1ß, and caspase-1 through LSCM. In intestinal inflammation, B.b. and B.f. could trigger an increase in NGF and NT-3 expression in EGCs in order to protect the intestine. Furthermore, B.b. and B.f. could upregulate NLRP3 expression in EGCs and promote an inflammatory response. B.b. had a dual regulatory role in EGC NLRP6 expression, while B.f. inhibited NLRP6 protein expression. Moreover, B.b. could decrease the expression of IL-18, IL-1ß, and caspase-1 in EGCs in order to inhibit the inflammatory response. Contrary to this, B.f. could upregulate IL-18, IL-1ß, and caspase-1 expression in EGCs in order to promote the inflammatory response. B.b. and B.f. can influence the expression of NGF, NT-3, NLRP3, NLRP6, IL-18, IL-1ß, and caspase-1 in EGCs in order to inhibit or promote intestinal inflammation.


Asunto(s)
Bacteroides fragilis/metabolismo , Bifidobacterium bifidum/metabolismo , Factor Neurotrófico Derivado de la Línea Celular Glial/metabolismo , Inflamasomas/metabolismo , Inflamación/metabolismo , Neuroglía/metabolismo , Probióticos/metabolismo , Animales , Microbioma Gastrointestinal , Intestinos , Lipopolisacáridos/farmacología , Masculino , Microscopía Confocal , Ratas , Ratas Sprague-Dawley
11.
Plant Cell Rep ; 39(6): 709-722, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32140767

RESUMEN

KEY MESSAGE: The BnaNPR1-like gene family was identified in B. napus, and it was revealed that repression of BnaNPR1 significantly reduces resistance toS. sclerotiorum, intensifies ROS accumulation, and changes the expression of genes associated with SA and JA/ET signaling in response to this pathogen. The NONEXPRESSOR OF PATHOGENESIS-RELATED GENES1 (NPR1) and related NPR1-like genes play an important role in regulating plant defense. Oilseed rape (Brassica napus L.) is an important oilseed crop; however, little is known about the B. napus (Bna) NPR1-like gene family. Here, a total of 19 BnaNPR1-like genes were identified in the B. napus genome, and then named according to their respective best match in Arabidopsis thaliana (At), which led to the determination of B. napus homologs of every AtNPR1-like gene. Analysis of important protein domains and functional motifs indicated the conservation and variation among these homologs. Phylogenetic analysis of these BnaNPR1-like proteins and their Arabidopsis homologs revealed six distinct sub-clades, consequently indicating that their name classification totally conformed to their phylogenetic relationships. Further, B. napus transcriptomic data showed that the expression of three BnaNPR1s was significantly down-regulated in response to infection with Sclerotinia sclerotiorum, the most important pathogen of this crop, whereas BnaNPR2/3/4/5/6s did not show the expression differences in general. Further, we generated B. napus BnaNPR1-RNAi lines to interpret the effect of the down-regulated expression of BnaNPR1s on resistance to S. sclerotiorum. The results showed that BnaNPR1-RNAi significantly decreased this resistance. Further experiments revealed that BnaNPR1-RNAi intensified ROS production and changed defense responses in the interaction of plants with this pathogen. These results indicated that S. sclerotiorum might use BnaNPR1 to regulate specific physiological processes of B. napus, such as ROS production and SA defense response, for the infection.


Asunto(s)
Brassica napus/genética , Brassica napus/metabolismo , Genes de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Antiinfecciosos/metabolismo , Proteínas de Arabidopsis/genética , Ascomicetos/patogenicidad , Resistencia a la Enfermedad , Genoma de Planta , Filogenia , Enfermedades de las Plantas/microbiología , Plantas Modificadas Genéticamente , Interferencia de ARN , Alineación de Secuencia , Transcriptoma
12.
Plant Sci ; 291: 110362, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31928657

RESUMEN

Sclerotinia sclerotiorum causes a devastating disease in oilseed rape (Brassica napus), resulting in major economic losses. Resistance response of B. napus against S. sclerotiorum exhibits a typical quantitative disease resistance (QDR) characteristic, but the molecular determinants of this QDR are largely unknown. In this study, we isolated a B. napus mitogen-activated protein kinase gene, BnaMPK6, and found that BnaMPK6 expression is highly responsive to infection by S. sclerotiorum and treatment with salicylic acid (SA) or jasmonic acid (JA). Moreover, overexpression (OE) of BnaMPK6 significantly enhances resistance to S. sclerotiorum, whereas RNAi in BnaMPK6 significantly reduces this resistance. These results showed that BnaMPK6 plays an important role in defense to S. sclerotiorum. Furthermore, expression of defense genes associated with SA-, JA- and ethylene (ET)-mediated signaling was investigated in BnaMPK6-RNAi, WT and BnaMPK6-OE plants after S. sclerotiorum infection, and consequently, it was indicated that the activation of ET signaling by BnaMPK6 may play a role in the defense. Further, four BnaMPK6-encoding homologous loci were mapped in the B. napus genome. Using the allele analysis and expression analysis on the four loci, we demonstrated that the locus BnaA03.MPK6 makes an important contribution to QDR against S. sclerotiorum. Our data indicated that BnaMPK6 is a previously unknown determinant of QDR against S. sclerotiorum in B. napus.


Asunto(s)
Ascomicetos/fisiología , Brassica napus/genética , Proteínas Quinasas Activadas por Mitógenos/genética , Enfermedades de las Plantas/genética , Proteínas de Plantas/genética , Secuencia de Aminoácidos , Brassica napus/microbiología , Resistencia a la Enfermedad/genética , Proteínas Quinasas Activadas por Mitógenos/química , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Alineación de Secuencia
13.
Front Plant Sci ; 10: 1314, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31681392

RESUMEN

Sclerotinia sclerotiorum (Lib.) de Bary is an unusual pathogen which has the broad host range, diverse infection modes, and potential double feeding lifestyles of both biotroph and necrotroph. It is capable of infecting over 400 plant species found worldwide and more than 60 names have agriculturally been used to refer to diseases caused by this pathogen. Plant defense to S. sclerotiorum is a complex biological process and exhibits a typical quantitative disease resistance (QDR) response. Recent studies using Arabidopsis thaliana and crop plants have obtained new advances in mechanisms used by plants to cope with S. sclerotiorum infection. In this review, we focused on our current understanding on plant defense mechanisms against this pathogen, and set up a model for the defense process including three stages: recognition of this pathogen, signal transduction and defense response. We also have a particular interest in defense signaling mediated by diverse signaling molecules. We highlight the current challenges and unanswered questions in both the defense process and defense signaling. Essentially, we discussed candidate resistance genes newly mapped by using high-throughput experiments in important crops, and classified these potential gene targets into different stages of the defense process, which will broaden our understanding of the genetic architecture underlying quantitative resistance to S. sclerotiorum. We proposed that more powerful mapping population(s) will be required for accurate and reliable QDR gene identification.

14.
Ying Yong Sheng Tai Xue Bao ; 30(2): 668-676, 2019 Feb 20.
Artículo en Chino | MEDLINE | ID: mdl-30915820

RESUMEN

Farmland soil organic carbon (SOC) pool is a crucial component of global carbon cycle. Due to the widely-implemented straw returning, crop straws have become the primary exogenous carbon source for agricultural soils. The conversion and distribution of straw-derived carbon in soil directly affect the composition and contents of SOC, with further influence on soil nutrient cycling. Based on recent studies, this review investigated the factors impacting the transformation and distribution of straw-carbon; introduced the microbial composition that contributes to the assimilation of carbon from straw; and summarized the effects of straw-carbon on the composition, content, and turnover of SOC. Additionally, we proposed the future research regarding the effects of abiotic factors on the bio-transformation of straw-carbon; the interaction between biotic and abiotic factors during the straw carbon transformation processes; the coupling of carbon and nitrogen from straws into the soil carbon and nitrogen cycles; and the effective control over the transformation of straw-carbon that enters the active or stable soil organic carbon pool. The purpose was to reveal variation characteristics of SOC during straw returning, and provide theoretical basis and technical support for the efficient fertilization and carbon sequestration of straw returning.


Asunto(s)
Suelo , Agricultura , Carbono , Secuestro de Carbono
15.
Ying Yong Sheng Tai Xue Bao ; 27(9): 2823-2830, 2016 Sep.
Artículo en Chino | MEDLINE | ID: mdl-29732844

RESUMEN

Leaf litters of Pinus elliottii (needle-leaved) and Schima superba (broad-leaved), which are commonly found in subtropical regions of South China, were decomposed in a field for 0, 30, 60, 90, 150, 210, 240 and 365 d to evaluate changes in concentrations, compositions and properties, and amount of dissolved organic matter (DOM) released and dissolved organic carbon (DOC) in soil. Although the concentrations of DOM derived from S. superba were higher than those from P. elliottii, similar variation patterns of DOM characteristics (e.g., concentrations, composition and properties) were observed between the two types of litter during decomposition. The concentrations of DOM showed a downward trend. Upward trends were obtained for the aromatization and molecular mass of DOM, as well as fulvic acid and humic acid levels in DOM, while a downward trend was found for levels of simple aromatic proteins, such as tyrosine, in DOM. During the initial phase of decomposition, DOM was generally composed of hydrophilic neutral and acidic components, which were easily decomposed and transferred, and their effects on surface soil DOC were not significant. At later stages, DOM was mainly composed of humic and fulvic acid and other aromatic, complex structure substances, which could easily adsorb on soil, and decreased the DOC concentration of surface soil.


Asunto(s)
Hojas de la Planta/química , Suelo/química , Árboles , Adsorción , Benzopiranos/análisis , Carbono/análisis , China , Sustancias Húmicas/análisis , Pinus , Theaceae
16.
Ying Yong Sheng Tai Xue Bao ; 24(6): 1545-50, 2013 Jun.
Artículo en Chino | MEDLINE | ID: mdl-24066538

RESUMEN

Laboratory incubation test was conducted to study the effects of temperature on the CH4 emission from the leaves of subtropical common tree species Castanopsis carlesii, Schima superb, Cinnamomum chekiangense, Castsanopsis fabri, Cunninghamia lanceolata, and Citrus reticulata. Among the six tree species, only S. superb, C. reticulate, and C. fabri emitted CH4 at 10 degrees C. At above 20 degrees C, all the six species emitted CH4, and the average CH4 emission rate at above 30 degrees C (1.010 ng CH4 x g(-1) DM x h(-1)) was 2.96 times higher than that at 10-30 degrees C (0.255 ng CH4 x g(-1) DM x h(-1)). Moreover, increasing temperature had much more effects on the CH4 emission rate of C. reticulata and C. lanceolata than on that of the other four tree species. Incubation time affected the CH4 emission rate of all test tree species significantly, suggesting that the effects of temperature stress on the CH4 emission could be controlled by plant activity. Dry leaves could not emit CH4 no matter the temperature was very high or low. It was suggested that high temperature stress had important effects on the CH4 emission from subtropical tree leaves, and global warming could increase the CH4 emission from plants.


Asunto(s)
Metano/metabolismo , Hojas de la Planta/metabolismo , Temperatura , Árboles/metabolismo , Cinnamomum/metabolismo , Citrus/metabolismo , Técnicas de Cultivo , Cunninghamia/metabolismo , Árboles/crecimiento & desarrollo , Clima Tropical
17.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(8): 2086-9, 2011 Aug.
Artículo en Chino | MEDLINE | ID: mdl-22007390

RESUMEN

To remove the background signals from an IR spectrum is very useful and ideally all that remain in an IR spectrum are the desired absorption bands. Unfortunately, the removal of background bands is not always completely effective. In the present paper, an absorbance spectrum was obtained by scanning the same sample (polystyrene film or stearic acid KBr disc) both in background and sample single-beam measurements. It was found that a series of residual spikes appear in the strong absorption regions. The residuals are significantly different from that of random noise. There should be a nearly straight line according to theory analysis while spikes appear. Therefore those spikes are called anomalous absorption The experimental results indicate that anomalous absorption is related to the absorbance of infrared bands. If the absorbance of an infrared band is lower than 1.0, anomalous absorption can be suppressed thoroughly. In addition, absorption anomalies can be substantially reduced by reducing the spectral resolution of the spectrum. The reasons for anomalous absorption were discussed and how to prevent the appearance of anomalous absorption by selecting appropriate background samples were suggested.

19.
Artículo en Chino | MEDLINE | ID: mdl-21186525

RESUMEN

OBJECTIVE: To detect Human Cytomegalovirus (HCMV) DNA in urine samples from the following groups: pregnant women, sick newborns, hospitalized nephropathy patients, renal transplant recipients and normal population. Preliminarily study the relationship of HCMV infection and renal disease. METHODS: To detect HCMV DNA in morning urine samples by Real-time fluorescence quantitative PCR (FQ-PCR). RESULTS: The positive rates of HCMV DNA in the urine of pregnant women,sick newborns, hospitalized nephropathy patients, renal transplant recipients and normal population are 8.18%, 3.45%, 18.54%, 25.42%, 0.56%. CONCLUSION: The infection rates of HCMV in the urine of pregnant women and sick newborns are very high in Guangxi, it should take serious measures to prevent and control the situation. HCMV probably participate in the injury of kidney, and worsen the disease. It should be one of the causes of renal disease.


Asunto(s)
Infecciones por Citomegalovirus/epidemiología , Infecciones por Citomegalovirus/transmisión , Citomegalovirus/patogenicidad , Enfermedades Renales/epidemiología , China , Citomegalovirus/fisiología , Infecciones por Citomegalovirus/complicaciones , ADN Viral/análisis , Etnicidad , Femenino , Humanos , Recién Nacido , Enfermedades Renales/complicaciones , Trasplante de Riñón , Metotrexato/farmacología , Reacción en Cadena de la Polimerasa , Embarazo
20.
Biomed Environ Sci ; 23(2): 130-6, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20514988

RESUMEN

OBJECTIVE: The effect of dietary restriction, intense exercise and menstrual dysfunction on bone mineral density remains controversial. The aim of this study was to assess the skeletal health status and relationship between bone mineral density and nutrient intake, menstrual status, estrogen level and other factos in Chinese adolescent dancers. METHODS: Sixty dancers and 77 healthy controls underwent measurements of bone density, body composition, and estrogen level. Nutrient intake, menstrual status and physical activity were assessed with questionnaires. The correlation between these factors were analyzed. RESULTS: The dancers under study had a significantly lean body mass index (18.3 +/- 1.4 kg/m2 vs. 21.7 +/- 3.1 kg/m2), lower percentage of body fat (0.25 +/- 0.05 vs. 0.34 +/- 0.04) and later age at menarche (14.0 +/- 0.9 y vs. 13.0 +/- 1.3 y), and the estrogen level, daily calorie and fat intake in them were also lower than in the controls. All the dancers undertook intensive physical activity every day and up to 69% of them suffered from irregular menarche. Yet they had relatively high BMD and BMC of the total body and legs than the controls after adjusting for BMI and age. Site-specific BMD was positively correlated to BMI, body composition and training hours per week and negatively correlated to the age at menarche and menstrual frequency. CONCLUSIONS: The relatively high BMD and BMC of the dancers at the total body and legs were probably caused by high levels of weight-bearing physical activity. To ameliorate disordered eating, especially low energy intake might be helpful to prevent the Triad and to improve the bone health in adolescent dancers.


Asunto(s)
Densidad Ósea , Baile/fisiología , Adolescente , China/epidemiología , Baile/estadística & datos numéricos , Ingestión de Energía , Ejercicio Físico/fisiología , Femenino , Humanos , Trastornos de la Menstruación/epidemiología , Osteoporosis/prevención & control , Caracteres Sexuales
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