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PURPOSE: Non-alcoholic fatty liver disease (NAFLD) is considered as both a vital risk factor and a consequence of type 2 diabetes mellitus (T2DM). Low total testosterone (TT) is common in men with T2DM, contributing to increased risks of metabolic diseases. This study aimed to investigate the association between TT levels and the prevalence of NAFLD in men with T2DM. METHODS: In this cross-sectional study, 1005 men with T2DM were enrolled in National Metabolic Management Center (MMC) of First Affiliated Hospital of Wenzhou Medical University between January 2017 and August 2021. NAFLD was diagnosed using ultrasound as described by the Chinese Liver Disease Association. Overweight/obesity was defined as body mass index (BMI) ≥ 25 kg/m2 according to WHO BMI classifications. RESULTS: Individuals without NAFLD had higher serum TT levels than those with NAFLD. After adjustments for potential confounding factors, the top tertile was significantly associated with lower prevalence of NAFLD compared with the bottom tertile of TT level [odds ratio (OR) 0.303, 95% confidence interval (CI) 0.281-0.713; P < 0.001]. The association between TT with NAFLD in individuals with normal weight (OR 0.175, 95% CI 0.098-0.315; P < 0.001) was stronger than in individuals with overweight/obesity (OR 0.509, 95% CI 0.267-0.971; P = 0.040). There was a significant interaction of TT with overweight/obesity (P for interaction = 0.018 for NAFLD). CONCLUSION: Higher serum TT was significantly associated with a lower prevalence of NAFLD in men with T2DM. We found that the relationship of TT and NAFLD was stronger in individuals with non-overweight/obesity.
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Diabetes Mellitus Tipo 2 , Enfermedad del Hígado Graso no Alcohólico , Masculino , Humanos , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Enfermedad del Hígado Graso no Alcohólico/epidemiología , Enfermedad del Hígado Graso no Alcohólico/diagnóstico , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/epidemiología , Testosterona , Estudios Transversales , Obesidad/complicaciones , Obesidad/epidemiología , Obesidad/diagnóstico , Sobrepeso/complicaciones , Sobrepeso/epidemiología , Índice de Masa CorporalRESUMEN
Objective: To investigate the effect and molecular mechanism of ultra-conservative long non-coding RNA uc.77 in lung cancer. Methods: Lung cancer tissues and adjacent normal tissues were obtained from 61 patients with lung cancer who were diagnosed with lung cancer and underwent surgery from 2014 to 2016 in the General Hospital of the Southern Theater Command of the People's Liberation Army. Real-time fluorescence quantitative polymerase chain reaction (qRT-PCR) was used to detect the uc.77 relative expressions in normal human bronchial epithelial cells 16HBE, lung cancer cell lines, and 61 pair lung cancer tissues. Uc.77 siRNA was transfected into lung cancer cells to interfere with the expression of uc.77, qRT-PCR was used to verify the interference effect, CCK8 method and clone formation experiment were used to detect cell proliferation ability, flow cytometry was used to detect apoptosis and cell cycle changes. H1299 cells transfected with uc.77 siRNA were injected into the subcutaneous right side of BALB/c nude mice to construct a tumor-bearing model for exploring the role of uc.77 on tumor growth. Western blot and qRT-PCR methods were used to detect the protein and mRNA expressions of p21. Results: The relative expression levels of uc.77 in lung cancer cell lines 95D, H1299, A549, H460, H446 and 16HBE-T were significantly higher than that of 16HBE cells (P<0.05). The uc.77 RNA expression levels of lung cancer tissues was significantly higher than that of the adjacent normal tissues (P<0.001). In addition, increased lncRNA uc.77 expression was significantly associated with big tumor size, lymph node metastasis and advanced TNM stage (P<0.05). After transfection with uc.77 siRNA, the expressions of uc.77 in H1299, 95-D and 16HBE-T cells were reduced (P<0.05), and the cell proliferation capacities were reduced at 48 hours and 72 hours (P<0.05). After transfection with uc.77 siRNA-1, the G(0)/G(1) phase cell ratio of H1299 siRNA-1 group [(71.86±3.46)%] was higher than those of H1299-control group [(47.62±5.48)%] and H1299 siRNA-NC group [(61.38±5.62)%, P<0.05], S phase cell ratio of H1299 siRNA-1 group [(14.99±3.61)%] was lower than those of H1299-control group [(34.95±7.05)%] and H1299 siRNA-NC group [(23.75±5.87)%, P<0.05], the apoptosis rate of H1299 siRNA-1 group [(4.90±1.80)%] was higher than those of H1299-control group [(3.30±0.80)%] and H1299 siRNA-NC group [(2.80±1.20)%, P<0.05], the colony formation rate of H1299 siRNA-1 group [(19.20±2.00)%] was lower than those of H1299 control group [(32.60±2.00)%] and H1299 siRNA-NC group [(34.40±1.00)%, P<0.05]. The results of the nude mice tumor formation experiment showed that the tumor volume of the H1299 siRNA-1 group was significantly lower than those of the H1299-control group and the H1299-negative control group (P<0.05), the average tumor weight of H1299 siRNA-1 group was significantly lower than those of H1299-control group and H1299-negative control group (P<0.05), tumor cell growth marker Ki-67 in the H1299 siRNA-1 group showed weak positive, and Ki-67 in the H1299-control group and H1299-negative control group showed positive. The result of qRT-PCR analysis showed that the mRNA expression level of p21 in H1299 siRNA-1 group (2.57±0.45) was higher than those in H1299 control group (1.00±0.00, P=0.001) and H1299 siRNA-NC group (1.52±0.37, P=0.009). The result of western blotting analysis also showed that the expression of p21 protein level in H1299 siRNA-1 group increased. Conclusions: The expression of ultraconserved long non-coding RNA uc.77 is elevated in lung cancer cell lines and lung cancer tissues. Silencing the expression of ultraconservative long noncoding RNA uc.77 can inhibit tumor growth, and blocking uc.77 expression may be a potential therapeutic target for lung cancer.
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Neoplasias Pulmonares , ARN Largo no Codificante , Ratones , Animales , Humanos , ARN Largo no Codificante/metabolismo , Ratones Desnudos , ARN Interferente Pequeño/metabolismo , Antígeno Ki-67/metabolismo , Línea Celular Tumoral , Neoplasias Pulmonares/patología , Proliferación Celular , Apoptosis/genética , ARN Mensajero , Regulación Neoplásica de la Expresión GénicaRESUMEN
Graphene oxide (GO) was utilized to investigate the role of carboxylic acid groups in the reduction of nitric oxide (NO) for the first time. As a result, GO with sufficient carboxylic acid groups reduced 45% of NO at 100 °C. However, GO without these oxygen-containing groups barely reduced NO (lower than 5%) under the same conditions. After reduction of NO, the carboxylic acid group content on GO decreased from 8.32 to 5.22 mmol g-1. Simultaneously, the anhydride group content increased from 0.14 to 0.28 mmol g-1. FTIR spectroscopy also indicated that the carboxylic acid groups transformed into anhydride and lactone groups. Moreover, both transient kinetics and TG-MS studies demonstrated that reactive intermediates formed during the reaction between NO and GO at 100 °C. Based on these results, it was proposed that the carboxylic acid groups participated in NO reduction by consumption and regeneration. This mechanism explains why carbon is usually an effective reductant and catalyst support for NO removal at low temperature.
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Objective: To conduct an epidemiological investigation of two leptospirosis death cases reported in Guizhou Province in 2014. Methods: The information of the patients were investigated and analyzed. The serological detection, samples of the two patients was detected using ELISA and microscopic agglutination test (MAT). Leptospira carrier status of murine host animal in the living environment of the two patients was investigated in October and November of 2014. Leptospires in the kidney were cultured and isolated, the isolates were identified using Leptospira specific PCR and further identified with serogroup specific PCR and the conventional MAT. The relativity between the carrier status of murine and the death cases of human leptospirosis was analyzed. Results: The two death cases of human leptospirosis came from Liping County and the clinical symptoms were consistent with the diagnosis criteria for Leptospirosis. The results of ELISA detection showed that the anti-Leptospira antibody was positive for one of the death cases, MAT identified the serum reacted with sera-group icterohaemorrhagiae Leptospira, while the serum sample of the other case was failed to perform antibody detection due to hemolysis. 1 600 traps were placed in the living environment of the two death cases and 183 murine rodents were trapped. The murine density was 11.44% (183/1 600); 40 leptospirea suspected strains were isolated and all of them were isolated from Apodemus agrarius. The positive rate was 21.86% (40/183); 95 Apodemus agrarius were trapped and the murine density was 5.93% (95/1 600). Species specific PCR identified all the 40 strains as Leptospire. Serogroup specific PCR further identification showed that they were iterohaemorrahgiae serogroup Leptospria. interrogans. Conclusion: Anti-iterohaemorrahgiae Leptospira antibody was detected from one of the two patients. 40 strains of iterohaemorrahgiae serogroup Leptospira interrogans were isolated and all of them were isolated from Apodemus agrarius in the living environment and the serogroup of the Leptospira matched with the serological detection results from patients, which indicated that the two death cases were caused by the infection of iterohaemorrahgiae serogroup Leptospira interrogans, and Apodemus agrarius were the potential source of infection.
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Portador Sano/veterinaria , Leptospira interrogans/genética , Leptospira/clasificación , Leptospirosis/diagnóstico , Pruebas de Aglutinación , Animales , Anticuerpos Antibacterianos , Portador Sano/epidemiología , Portador Sano/microbiología , China/epidemiología , Ensayo de Inmunoadsorción Enzimática , Genotipo , Humanos , Leptospira/genética , Leptospira/aislamiento & purificación , Leptospira interrogans/clasificación , Leptospira interrogans/aislamiento & purificación , Leptospirosis/epidemiología , Leptospirosis/mortalidad , Murinae , Reacción en Cadena de la Polimerasa , Roedores , SerogrupoRESUMEN
AIMS: The aim of this study is to isolate and identify an endophytic fungus with antibacterial activity from the Asian medicinal and culinary plant Lilium lancifolium and to study the characteristics of its major antibacterial fractions. METHODS AND RESULTS: After strict sample sterilization, an endophytic fungus BH-3 with great antibacterial activity against Leuconostoc mesenteroides was isolated from the bulbs of L. lancifolium and was identified as Fusarium oxysporum on the basis of internal transcribed spacer (ITS) rDNA sequence and morphological traits. After partial purification including superfiltration and gel filtration, the major antibacterial fractions were found to be the substances with the molecular mass ranging from 35 to 60kDa, mainly 55kDa. The partially purified antibacterial fractions were stable at thermal processes, with more than 80% of activity left at 60°C for 1h, and even 70·75% left at 121°C for 15min. 90·33-98·97% of activity was observed in the pH range of 4·0-7·0. But the fractions were sensitive to different proteases. CONCLUSIONS: Endophytic strain F. oxysporum BH-3 isolated from the bulbs of L. lancifolium produced protein-like antibacterial metabolites. The antibacterial assay against Leuc. mesenteroides indicated that the fractions were stable at thermal processes and wide pH conditions, but sensitive to proteolyses. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides an increasing understanding of endophytic F. oxysporum in L. lancifolium and its metabolites, which have a great potential in food industry as antibacterial agents.
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Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Fusarium/química , Leuconostoc/efectos de los fármacos , Lilium/microbiología , Antibacterianos/metabolismo , ADN Ribosómico , ADN Espaciador Ribosómico/genética , Fusarium/genética , Fusarium/aislamiento & purificación , Leuconostoc/crecimiento & desarrollo , Pruebas de Sensibilidad Microbiana , Técnicas de Tipificación Micológica , Raíces de Plantas/microbiologíaRESUMEN
It has been rarely questioned as to whether the enrichment of specific bacterial taxa found in the rhizosphere of a given plant species changes with different soil types under field conditions and under similar climatic conditions. Understanding tree microbiome interactions is essential because, in contrast to annual plants, tree species require decades to grow and strongly depend on the nutritive resources of the soil. In this context, we tested using a natural toposequence the hypothesis that beech trees select specific taxa and functions in their rhizosphere based on the soil conditions and their nutritive requirements. Our 16S rRNA gene pyrosequencing analyses revealed that the soil type determines the taxa colonizing the beech rhizosphere. A rhizosphere effect was observed in each soil type, but a stronger effect was observed in the nutrient-poor soils. Although the communities varied significantly across the toposequence, we identified a core beech rhizosphere microbiome. Functionally, GeoChip analyses showed a functional redundancy across the toposequence, with genes related to nutrient cycling and to the bacterial immune system being significantly enriched in the rhizosphere. Altogether, the data suggest that, regardless of the soil conditions, trees enrich variable bacterial communities to maintain the functions necessary for their nutrition.
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Microbiota , Rizosfera , Microbiología del Suelo , Carbono/metabolismo , Metagenoma , Metagenómica/métodos , Interacciones Microbianas , ARN Ribosómico 16S , Metabolismo SecundarioRESUMEN
The goal of this research was to investigate the influence of the error rate of sequence determination on the differentiation of cloned SSU rRNA gene sequences for assessment of community structure. SSU rRNA cloned sequences from groundwater samples that represent different bacterial divisions were sequenced multiple times with the same sequencing primer. From comparison of sequence alignments with unedited data, confidence intervals were obtained from both a 'double binomial' model of sequence comparison and by non-parametric methods. The results indicated that similarity values below 0.9946 are likely derived from dissimilar sequences at a confidence level of 0.95, and not sequencing errors. The results confirmed that screening by direct sequence determination could be reliably used to differentiate at the species level. However, given sequencing errors comparable to those seen in this study, sequences with similarities above 0.9946 should be treated as the same sequence if a 95% confidence is desired.
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ADN Bacteriano/genética , ARN Ribosómico/genética , Análisis de Secuencia de ADN/métodos , Microbiología del Agua , Secuencia de Bases , Intervalos de Confianza , ADN Bacteriano/química , Agua Dulce , Filogenia , Reacción en Cadena de la Polimerasa , ARN Ribosómico/química , ARN Ribosómico 16S/química , ARN Ribosómico 16S/genética , Alineación de SecuenciaRESUMEN
Although the skeleton is one of the predominant sites for breast cancer metastasis, why breast cancer cells often become dormant after homing to bone is not well understood. Here, we reported an intrinsic self-defense mechanism of bone cells against breast cancer cells: a critical role of connexin (Cx) 43 hemichannels in osteocytes in the suppression of breast cancer bone metastasis. Cx43 hemichannels allow passage of small molecules between the intracellular and extracellular environments. The treatment of bisphosphonate drugs, either alendronate (ALN) or zoledronic acid (ZOL), opened Cx43 hemichannels in osteocytes. Conditioned media (CM) collected from MLO-Y4 osteocyte cells treated with bisphosphonates inhibited the anchorage-independent growth, migration and invasion of MDA-MB-231 human breast cancer cells and Py8119 mouse mammary carcinoma cells, and this inhibitory effect was attenuated with Cx43(E2), a specific hemichannel-blocking antibody. The opening of osteocytic Cx43 hemichannels by mechanical stimulation had similar inhibitory effects on breast cancer cells and this inhibition was attenuated by Cx43(E2) antibody as well. These inhibitory effects on cancer cells were mediated by ATP released from osteocyte Cx43 hemichannels. Furthermore, both Cx43 osteocyte-specific knockout mice and osteocyte-specific Δ130-136 transgenic mice with impaired Cx43 gap junctions and hemichannels showed significantly increased tumor growth and attenuated the inhibitory effect of ZOL. However, R76W transgenic mice with functional hemichannels but not gap junctions in osteocytes did not display a significant difference. Together, our studies establish the specific inhibitory role of osteocytic Cx43 hemichannels, and exploiting the activity of this channel could serve as a de novo therapeutic strategy.
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Neoplasias Óseas/secundario , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Conexinas/genética , Osteólisis/genética , Animales , Fenómenos Biomecánicos , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Movimiento Celular/genética , Proliferación Celular/genética , Conexina 43/genética , Conexina 43/metabolismo , Conexinas/metabolismo , Difosfonatos/farmacología , Femenino , Técnicas de Inactivación de Genes , Humanos , Activación del Canal Iónico/efectos de los fármacos , Ratones , Ratones Transgénicos , Osteocitos/metabolismoRESUMEN
Objective:To investigate effect of hydrogen peroxide (H2O2) in the lateral line hair cell growth and regeneration after damage on zebrafish. Method:Select 5 dpf zebrafish, each group of 10, randomly divided into A control group: the system of water culture. B H2O2 group: 10 µmol/L, 20 µmol/L H2O2 solution to replace three times a day. C neomycin group: treatment with system water after 1 h culture by 200 µmol/L neomycin. D neomycin + H2O2 group: 20 µmol/L H2O2 solution to replace three times a day after 200 µmol/L neomycin treatment for 1 h. E cisplatin group: treatment with system water after 3 h culture by 1 000 µmol/L cisplatin. F cisplatin + H2O2 group: 20 µmol/L H2O2 solution to replace three times a day after 1 000 µmol/L cisplatin treatment for 3 h. Each group in H2O2 treatment for 0 h, 24 h, 48 h was marked their hair cells by immunofluorescence method and count the P1, P7, P8 neuromasts under the fluorescence microscope. Repeat 3 times. Result:The number of hair cells on P1, P7, P8 three neuramasts among 5 to 7 dpf zebrafish were 9.364±0.901(n=11),9.645±0.598(n=15),9.922±0.862(n=13), no obvious difference (P>0.05); 10µmol/L, 20µmol/L H2O2 treated zebrafish for 48 h, the numbers were 11.540±0.741,11.905±0.607,compaired with the control group(10.841±0.389), P<0.05; neomycin+ H2O2 48 h and neomycin 48 h respectively were 10.600±0.689,8.767±0.603, P<0.01; cisplatin+ H2O2 48 h and cisplatin 48 h were 5.967±1.086,5.633±1.548, P>0.05. Conclusion:20 µmol/L H2O2 promotes the development of lateral line hair cells of zebrafish; H2O2 promotes the regeneration of the lateral line hair cells after injury of neomycin, but not cisplatin.
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Células Ciliadas Auditivas/efectos de los fármacos , Peróxido de Hidrógeno/farmacología , Animales , Proliferación Celular/efectos de los fármacos , Proteínas Fluorescentes Verdes/metabolismo , Larva , Neomicina , Regeneración , Pez CebraRESUMEN
OBJECTIVE: The roles of serum free light chain ratio (sFLCR) in the diagnosis and prognosis of newly diagnosed multiple myeloma (NDMM) patients were analyzed. METHODS: The clinical data was retrospectively analyzed for 82 newly diagnosed multiple myeloma (NDMM) patients in the first affiliated hospital of Soochow University from September 28, 2012 to July 18, 2105. The serum free light chain levels were measured and κ/λ ratios were calculated, so we could analyze the roles of sFLCR in the diagnosis and prognosis of newly diagnosed multiple myeloma (NDMM) patients. RESULTS: It was 85.5% (70/82) positive of M protein by serum protein electrophoresis (SFE) and 93.9%(77/82) by serum immunofixation electrophoresis (IFE). Both sFLC and sFLCR abnormalities were 96.3% (79/82). The estimated 40-months overall survival was 87% for the high free light chain ratio group (sFLCR ≥100 or≤0.01) and 61% for the low free light chain ratio group (0.01Asunto(s)
Cadenas Ligeras de Inmunoglobulina/sangre
, Mieloma Múltiple/diagnóstico
, Células de la Médula Ósea
, Humanos
, Hibridación Fluorescente in Situ
, Mieloma Múltiple/sangre
, Proteínas de Mieloma/química
, Pronóstico
, Insuficiencia Renal/complicaciones
, Estudios Retrospectivos
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Extracellular ATP has been shown to either inhibit or promote cancer growth and migration; however, the mechanism underlying this discrepancy remained elusive. Here we demonstrate the divergent roles of ATP and adenosine released by bone osteocytes on breast cancers. We showed that conditioned media (CM) collected from osteocytes treated with alendronate (AD), a bisphosphonate drug, inhibited the migration of human breast cancer MDA-MB-231 cells. Removal of the extracellular ATP by apyrase in CM abolished this effect, suggesting the involvement of ATP. ATP exerted its inhibitory effect through the activation of purinergic P2X receptor signaling in breast cancer cells evidenced by the attenuation of the inhibition by an antagonist, oxidized ATP, as well as knocking down P2X7 with small interfering RNA (siRNA), and the inhibition of migration by an agonist, BzATP. Intriguingly, ATP had a biphasic effect on breast cancer cells-lower dosage inhibited but higher dosage promoted its migration. The stimulatory effect on migration was blocked by an adenosine receptor antagonist, MRS1754, ARL67156, an ecto-ATPase inhibitor, and A2A receptor siRNA, suggesting that in contrast to ATP, adenosine, a metabolic product of ATP, promoted migration of breast cancer cells. Consistently, non-hydrolyzable ATP, ATPγS, only inhibited but did not promote cancer cell migration. ATP also had a similar inhibitory effect on the Py8119 mouse mammary carcinoma cells; however, adenosine had no effect owing to the absence of the A2A receptor. Consistently, ATPγS inhibited, whereas adenosine promoted anchorage-independent growth of MDA-MB-231 cells. Our in vivo xenograft study showed a significant delay of tumor growth with the treatment of ATPγS. Moreover, the extent of bone metastasis in a mouse intratibial model was significantly reduced with the treatment of ATPγS. Together, our results suggest the distinct roles of ATP and adenosine released by osteocytes and the activation of corresponding receptors P2X7 and A2A signaling on breast cancer cell growth, migration and bone metastasis.
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Adenosina Trifosfato/metabolismo , Adenosina/metabolismo , Neoplasias de la Mama/patología , Receptor de Adenosina A2A/metabolismo , Receptores Purinérgicos P2X/metabolismo , Adenosina Trifosfato/análogos & derivados , Adenosina Trifosfato/farmacología , Alendronato/farmacología , Animales , Apirasa/farmacología , Conservadores de la Densidad Ósea/farmacología , Neoplasias Óseas/secundario , Neoplasias de la Mama/genética , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular , Femenino , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Desnudos , Trasplante de Neoplasias , Osteocitos/metabolismo , Interferencia de ARN , ARN Interferente Pequeño , Receptor de Adenosina A2A/genética , Receptores Purinérgicos P2X/genética , Transducción de Señal , Trasplante HeterólogoRESUMEN
We studied the microbial functional diversity, biochemical activity, heavy metals (HM) availability and soil toxicity of Cd, Pb and Zn contaminated soils, kept under grassland or short rotation coppice (SRC) to attenuate the risks associated with HM contamination and restore the soil ecological functions. Soil microbial functional diversity was analyzed by the GeoChip, a functional gene microarray containing probes for genes involved in nutrient cycling, metal resistance and stress response. Soil under SRC showed a higher abundance of microbial genes involved in C, N, P and S cycles and resistance to various HM, higher microbial biomass, respiration and enzyme activity rates, and lower HM availability than the grassland soil. The linkages between functional genes of soil microbial communities and soil chemical properties, HM availability and biochemical activity were also investigated. Soil toxicity and N, P and Pb availability were important factors in shaping the microbial functional diversity, as determined by CCA. We concluded that in HM contaminated soils the microbial functional diversity was positively influenced by SRC management through the reduction of HM availability and soil toxicity increase of nutrient cycling. The presented results can be important in predicting the long term environmental sustainability of plant-based soil remediation.
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Variación Genética , Metales Pesados/metabolismo , Rotación , Salix/metabolismo , Microbiología del Suelo , Contaminantes del Suelo/metabolismo , Suelo/química , Biodegradación Ambiental , Biomasa , Metales Pesados/aislamiento & purificación , Contaminantes del Suelo/aislamiento & purificaciónRESUMEN
We developed a quantitative competitive PCR (QC-PCR) system to detect and quantify copper-denitrifying bacteria in environmental samples. The primers were specific to copper-dependent nitrite reductase gene (nirK). We were able to detect about 200 copeis of nirK in the presence of abundant non-specific target DNA and about 1.2 x 10(3)Pseudomonas sp. G-179 cells from one gram of sterilized soil by PCR amplification. A 312-bp nirK internal standard (IS) was constructed, which showed very similar amplification efficiency with the target nirKfragment (349 bp) over 4 orders of magnitude (10(3)-10(6)). The accuracy of this system was evaluated by quantifying various known amount of nirK DNA. The linear regressions were obtained with a R(2) of 0.9867 for 10(3)copies of nirK, 0.9917 for 10(4) copies of nirK, 0.9899 for 10(5) copies of nirK and 0.9846 for 10(6) copies of nirK. A high correlation between measured nirK and calculated nirK (slope of 1.0398, R(2)=0.9992) demonstrated that an accurate measurement could be achieved with this system. Using this method, we quantified nirK in several A-horizon and stream sediment samples from eastern Tennessee. In general, the abundance of nirK was in the range of 10(8)-10(9) copies g soil(-1) dry weight. The nirK content in the soil samples appeared correlated with NH(4)(N) content in the soil. The activities of copper-denitrifying bacteria were evaluated by quantifying cDNA of nirK. In most of sample examined, the content of nirK cDNA was less than 10(5) copies g soil(-1) dry weight. Higher nirK cDNA content (>10(6) copies g soil(-1) dry weight) was detected from both sediment samples at Rattlebox Creek and the Walker Branch West Ridge. Although the stream sediment samples at the Walker Branch West Ridge contained less half of the nirK gene content as compared to A-horizon sample, the activities of copper-denitrifying bacteria were almost 600 times higher than in the A-horizon sample.
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Cobre/metabolismo , Sedimentos Geológicos/microbiología , Nitrato Reductasas/genética , Reacción en Cadena de la Polimerasa/métodos , Pseudomonas/genética , Microbiología del Suelo , ADN Bacteriano/química , ADN Bacteriano/genética , Nitrato-Reductasa , Nitrato Reductasas/química , Pseudomonas/enzimologíaRESUMEN
Recently, we demonstrated that a matrix-assisted laser desorption/ionization time-of-flight mass spectrometer (MALDI-TOF MS) can be used to determine the molecular weight of polymerase chain reaction (PCR) products of intact 16S rRNA regions and to profile their restriction digests. This is the first time that MALDI-TOF MS with ultraviolet (UV) photoionization has been used to analyze a PCR product of approximately 1600 nucleotides in length.
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ADN Bacteriano/análisis , ADN Ribosómico/análisis , ARN Ribosómico 16S/genética , Espectrometría de Masa por Láser de Matriz Asistida de Ionización DesorciónRESUMEN
Epidemiological studies of lung cancer in Chinese women indicated that factors other than cigarette smoking are related to lung cancer risk. A case-control study suggested that indoor air pollution, particularly from cooking oil emissions, may be involved. Condensates of volatile emissions from rapeseed and soybean cooking oils were prepared and found to be genotoxic in short-term tests including the Salmonella mutation assay, SV50 forward-mutation assay, and sister-chromatid exchange assay, as well as the micronucleus assay in mouse bone marrow. In contrast, condensates from rapeseed oil with butylated hydroxyanisole or hydrogenated rapeseed oil were not mutagenic, implicating oxidation products as the cause for mutagenicity. Peanut oil and lard condensates were not mutagenic in any assay. The association of exposure to Chinese rapeseed cooking-oil emissions and lung-cancer risk may be related to the mutagenic component of these condensates.
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Contaminación del Aire Interior , Culinaria , Mutágenos/toxicidad , Aceites Volátiles/toxicidad , Aceites de Plantas/toxicidad , Animales , Arachis , Brassica , Línea Celular , China , Cricetinae , Cricetulus , Ácidos Linolénicos/toxicidad , Neoplasias Pulmonares/inducido químicamente , Masculino , Ratones , Pruebas de Micronúcleos , Pruebas de Mutagenicidad , Salmonella typhimurium/efectos de los fármacos , Salmonella typhimurium/genética , Intercambio de Cromátides Hermanas , Aceite de Soja/toxicidadRESUMEN
A rapid and sensitive method for quantifying parthenolide in feverfew herb (Tanacetum parthenium) was developed that is significantly faster than those reported in the literature. The extraction system consisted of acetonitrile/water (90:10, v/v) in a bottle with stirring for 30 min. Both Soxhlet and bottle-stirring extractions were studied. Samples were analyzed using high-performance liquid chromatography with a Cosmosil C18-AR column (150 x 4.6 mm, 5 microm, 120 A). The mobile phase consisted of acetonitrile/water (55:45, v/v) with a flow rate of 1.5 mL/min and UV detection at 210 nm. Analysis time was 6 min, with a detection limit of 0.10 ng on column. The calibration curve was linear over a range of 0.160-850 microg/mL parthenolide with R(2) = 0.9999. Replicate tests indicated good reproducibility of the method with an RSD% = 0.88 (n = 10). Spike recovery of parthenolide was found to be 99.3% with an RSD% = 1.6 (n = 6).
Asunto(s)
Extractos Vegetales/química , Plantas Medicinales/química , Sesquiterpenos/aislamiento & purificación , Tanacetum parthenium/química , Cromatografía Líquida de Alta Presión/métodos , Indicadores y Reactivos , Sesquiterpenos/químicaRESUMEN
Computer simulations have been used by us since the early 1970s to gain an understanding of the spacing and movement patterns of confined animals. The work has progressed from the early stages, in which we used randomly positioned points, to current investigations of animats (computer-simulated animals), which show low levels of learning via artificial neural networks. We have determined that 1) pens of equal floor area but of different shape result in different spatial and movement patterns for randomly positioned and moving animats; 2) when group size increases under constant density, freedom of movement approaches an asymptote at approximately six animats; 3) matching the number of animats with the number of corners results in optimal freedom of movement for small groups of animats; and 4) perimeter positioning occurs in groups of animats that maximize their distance to first- and second-nearest neighbors. Recently, we developed animats that move, compete for social dominance, and are motivated to obtain resources (food, resting sites, etc.). We are currently developing an animat that learns its behavior from the spatial and movement data collected on live pigs. The animat model is then used to pretest pen designs, followed by new pig spatial data fed into the animat model, resulting in a new pen design to be tested, and the steps are repeated. We believe that methodologies from artificial-life and artificial intelligence can contribute to the understanding of basic animal behavior principles, as well as to the solving of problems in production agriculture in areas such as animal housing design.
Asunto(s)
Inteligencia Artificial , Simulación por Computador , Vivienda para Animales , Modelos Biológicos , Porcinos/fisiología , Animales , Conducta Animal , Procesamiento de Imagen Asistido por Computador , MovimientoRESUMEN
This study evaluated patient-initiated single-dose antibiotic prophylaxis and continuous long-term low-dose daily antibiotic use for the prevention of recurrent urinary tract infections (UTI) in 68 postmenopausal women. The women were randomized to take a low-dose antibiotic each night (continuous group, n = 37) or a single-dose antibiotic each time they experienced conditions predisposing to UTI (intermittent group, n = 31). During the 12-month study, 1.4 and 1.9 UTIs/patient developed in the continuous and the intermittent groups, respectively, which was significantly lower than the incidence of UTIs in the previous 12 months in these patients (4.7 and 5.1 UTIs/patient, respectively). The incidence of gastro intestinal adverse events was significantly lower in the intermittent group compared with the continuous group (9.1% versus 30.0%). In conclusion, patient-initiated single-dose intermittent antibiotic prophylaxis was as effective as low-dose daily antibiotic prophylaxis in the treatment of recurrent UTIs in post menopausal women and was associated with fewer gastrointestinal adverse events.
Asunto(s)
Antibacterianos/efectos adversos , Antibacterianos/uso terapéutico , Profilaxis Antibiótica/efectos adversos , Posmenopausia/efectos de los fármacos , Infecciones Urinarias/tratamiento farmacológico , Infecciones Urinarias/prevención & control , Antibacterianos/farmacología , China/epidemiología , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Incidencia , Persona de Mediana Edad , Recurrencia , Factores de Riesgo , Resultado del Tratamiento , Infecciones Urinarias/epidemiologíaRESUMEN
BACKGROUND: To investigate the epidemic situation of Japanese encephalitis (JE) in three provinces, Guizhou, Sichuan, and Hubei in 2005. METHODS: Information about epidemic situation of JE, mosquitoes specimens were collected and titers of JE virus in hosts in the above three surveillance sites were determined. RESULTS: The reported cases of JE in Guizhou, Sichuan, and Hubei province accounted for 40.7% of total cases in 2005 in China. The numbers of cases in Guizhou and Sichuan ranked at the first two in China, morbidity exceeded 1/100,000, which was higher than average level in China. Zero to 10 years old children accounted for 90% in reported cases. Most of the cases were children lived at home. Almost all JE cases were presented from June to September, but most cases were reported between July and August. Investigaton of the density of vector showed that the dominant mosquitoes were Culex, especially the Culex tritaeniorhynchus. CONCLUSION: The epidemic status of JE was similar among the three provinces and the whole country. The number of JEV cases in Guizhou and Sichuan were the highest in China.