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1.
Front Microbiol ; 14: 1292959, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38029118

RESUMO

Biochar as an agricultural soil amendment plays vital roles in mediating methane (CH4) and nitrous oxide (N2O) emissions in soils. The link between different types of biochar, bulk soil, and rhizosphere microbial communities in relation to CH4 and N2O emissions is being investigated in this study. The rice pot experiment was conducted using biochar at two temperatures (300°C and 500°C) in combination with three biochar levels (0, 2, 10% w/w). Soil properties and the abundance of genes associated with CH4 and N2O emissions from both rhizosphere and bulk soils were investigated. The study also aimed to examine the structure of microbial communities (pmoA, nosZ) in rhizosphere and bulk soils whereas CH4 and N2O emissions were monitored while growing rice. Results showed that biochar at 300°C and 10% incorporation significantly increased the CH4 emissions by up to 59% rise compared to the control group. Random Forest analysis revealed that the ratio of mcrA/pmoA along with the abundance of mcrA from both rhizosphere and bulk soils, the abundance of AOA, TN, DOC, and the community composition of pmoA-harboring microorganisms from both bulk and rhizosphere soils were important predictors of CH4 emissions. Therefore, the ratio of mcrA/pmoA in rhizosphere soil and the abundance of AOA in bulk soil were the main factors influencing CH4 emissions. Variation Partitioning Analysis (VPA) results indicated that the effects of these factors on bulk soil were 9% of CH4 emissions variations in different treatments, which contributed more than rhizosphere soils' factors. Moreover, random forest analysis results indicated that the abundance of AOB in bulk soil was the most important predictor influencing N2O emissions. The VPA result revealed that the factors in rhizosphere soil could explain more than 28% of the variations in N2O emissions. Our study highlights that rhizosphere soil has a more significant effect than bulk soil on N2O production. Our findings further the understanding of the link between bulk and rhizosphere attributes, and their impact on CH4 and N2O emissions in paddy soils. In summary, we recommend the application of biochar at 500°C and 2% incorporation rate for agricultural production in the area.

2.
Front Endocrinol (Lausanne) ; 14: 1131564, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37152944

RESUMO

Background: There is no consensus on whether intravenous rehydration must be added after preoperative phenoxybenzamine (PXB) administration for pheochromocytoma. The aim of this study is to investigate whether abandonment of intravenous volume expansion after PXB administration is associated with intraoperative hemodynamic instability. Methods: 83 Patients with pheochromocytoma received surgical treatment in the Department of Urology, Handan First Hospital, between October 2014 and July 2022. All patients were subclassified into either the hemodynamic stability group (HS group) or the hemodynamic instability group (HU group) according to whether intraoperative hemodynamic instability occurred, with 51 cases in HS group and 32 cases in HU group. Differences in data between the two groups were examined, and the risk factors for intraoperative hemodynamic instability were analyzed using logistic regression. Results: The results of the analysis showed no statistically significant differences in age, sex, location of the tumor, surgical method, body mass index (BMI) ≥ 24 kg/m2, blood and urine catecholamine test results, preoperative oral PXB followed by combined intravenous volume expansion, proportion of patients with hypertension or diabetes mellitus or coronary heart disease between the two groups (P>0.05). The size of the tumor in the HS group was smaller than that in the HU group (5.3 ± 1.9 cm vs 6.2 ± 2.4 cm P=0.010). Multivariate analyses demonstrated that abandonment of intravenous volume expansion after preoperative receipt of α-blockers in patients with adrenal pheochromocytoma was not an independent risk factor for intraoperative hemodynamic instability. Only the tumor size (P=0.025) was an independent risk factor for intraoperative hemodynamic instability. Conclusion: The purpose of general preoperative intravenous fluid expansion is to prevent hypotension after the tumor has been resected. In the current study, we indicated that preoperative management of pheochromocytomas using the α-blocker PXB in combination with intravenous volume expansion does not further reduce the risk of intraoperative hemodynamic instability or postoperative complications compared with oral PXB alone. Therefore, our study supports preoperative management of pheochromocytoma with a single α-blocker, PXB, as sufficient.


Assuntos
Neoplasias das Glândulas Suprarrenais , Feocromocitoma , Humanos , Antagonistas Adrenérgicos alfa/uso terapêutico , Feocromocitoma/patologia , Fenoxibenzamina/uso terapêutico , Fatores de Risco , Hemodinâmica , Neoplasias das Glândulas Suprarrenais/complicações , Neoplasias das Glândulas Suprarrenais/cirurgia , Neoplasias das Glândulas Suprarrenais/patologia
3.
Zool Res ; 44(2): 249-258, 2023 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-36650064

RESUMO

Although 9.4 T magnetic resonance imaging (MRI) has been tested in healthy volunteers, its safety in diabetic patients is unclear. Furthermore, the effects of high static magnetic fields (SMFs), especially gradient vs. uniform fields, have not been investigated in diabetics. Here, we investigated the consequences of exposure to 1.0-9.4 T high SMFs of different gradients (>10 T/m vs. 0-10 T/m) on type 1 diabetic (T1D) and type 2 diabetic (T2D) mice. We found that 14 h of prolonged treatment of gradient (as high as 55.5 T/m) high SMFs (1.0-8.6 T) had negative effects on T1D and T2D mice, including spleen, hepatic, and renal tissue impairment and elevated glycosylated serum protein, blood glucose, inflammation, and anxiety, while 9.4 T quasi-uniform SMFs at 0-10 T/m did not induce the same effects. In regular T1D mice (blood glucose ≥16.7 mmol/L), the >10 T/m gradient high SMFs increased malondialdehyde ( P<0.01) and decreased superoxide dismutase ( P<0.05). However, in the severe T1D mice (blood glucose ≥30.0 mmol/L), the >10 T/m gradient high SMFs significantly increased tissue damage and reduced survival rate. In vitro cellular studies showed that gradient high SMFs increased cellular reactive oxygen species and apoptosis and reduced MS-1 cell number and proliferation. Therefore, this study showed that prolonged exposure to high-field (1.0-8.6 T) >10 T/m gradient SMFs (35-1 380 times higher than that of current clinical MRI) can have negative effects on diabetic mice, especially mice with severe T1D, whereas 9.4 T high SMFs at 0-10 T/m did not produce the same effects, providing important information for the future development and clinical application of SMFs, especially high-field MRI.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Camundongos , Animais , Glicemia , Diabetes Mellitus Tipo 1/veterinária , Campos Magnéticos , Diabetes Mellitus Tipo 2/veterinária
4.
Chronobiol Int ; 39(10): 1307-1319, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35880245

RESUMO

A variety of devices used in daily life and biomedical field will generate magnetic fields with different parameters, raising concern about their influences on people's physiological functions. Multiple experimental works have been devoted to the influences of magnetic fields on circadian rhythms, yet the findings were not always consistent due to the differences in magnetic field parameters and experimental organisms. Also, clear regulatory mechanisms have not been found. By systematizing the major achievements in research on magnetic and circadian rhythms based on magnetic flux density and analyzing the potential mechanisms of the magnetic fields affecting circadian rhythms, this review sheds light on the effects of magnetic fields on circadian rhythms and the potential applications in biomedicine.


Assuntos
Ritmo Circadiano , Campos Magnéticos , Ritmo Circadiano/fisiologia , Humanos
5.
BMC Urol ; 22(1): 7, 2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-35073883

RESUMO

BACKGROUND: Flexible ureteroscopic incision and drainage is a relatively new surgical method for treating parapelvic cysts. Considering that the intraoperative localization of the cyst may fail with a flexible ureteroscope, we use an innovative ultrasound-guided method to locate the cystic wall during flexible ureteroscopic surgery. METHODS: We retrospectively reviewed 17 consecutive cases of parapelvic renal cysts treated by ultrasound-guided flexible ureteroscopy between March 2017 and May 2020. The differences between the simple flexible ureteroscopic technique and ultrasound-guided flexible ureteroscopic technique were compared. The surgical procedures, postoperative complications, results and patient follow-ups were evaluated. RESULTS: The cyst wall was seen clearly in 10 patients with ureteroscopic vision. Another 7 patients underwent ultrasound-guided flexible ureteroscopic surgery since it was difficult to identify the cyst wall. The mean operative time was 25.9 ± 8.7 min and 37.1 ± 10.1 min for the conventional and modified techniques, respectively (P = 0.004); the mean time to search for cysts was 17.6 ± 5.8 min and 26.5 ± 8.4 min, respectively (P = 0.002); and the mean incision time was 7.1 ± 4.9 min and 12.1 ± 5.6 min, respectively (P = 0.000). All of the patients were followed-up for 12 months, and no serious complications or recurrence were observed. CONCLUSIONS: We demonstrated that it is feasible and safe to treat parapelvic renal cysts by ultrasound-guided flexible ureteroscopic incision and drainage. The small sample size and need for further studies were the limitations of our work.


Assuntos
Doenças Renais Císticas/cirurgia , Pelve Renal/cirurgia , Cirurgia Assistida por Computador , Ultrassonografia de Intervenção , Ureteroscópios , Ureteroscopia/métodos , Adulto , Idoso , Desenho de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
6.
Appl Microbiol Biotechnol ; 105(18): 6691-6706, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34463799

RESUMO

Natural water-soluble Monascus pigments (WSMPs) have been in increasing demand but have not been able to achieve industrial production due to the low production rate. This study aimed to improve the biosynthesis and secretion of extracellular yellow pigments (EYPs) through submerged fermentation with Monascus ruber CGMCC 10,910 supplemented with sodium starch octenyl succinate (OSA-SNa). The results demonstrated that the yield was 69.68% and 48.89% higher than that without OSA-SNa in conventional fermentation (CF) and extractive fermentation (EF), respectively. The mainly increased EYP components were Y3 and Y4 in CF, but they were mainly Y1 and Y2 as well as secreted intracellular pigments, including Y5, Y6, O1, and O2, in EF. Scanning electron microscopy analysis revealed that the mycelium presented an uneven surface profile with obvious wrinkles and small fragments with OSA-SNa. It was found that a higher unsaturated/saturated fatty acids ratio in the cell membrane resulted in increased permeability and facilitated the export of intracellular yellow pigments into the broth with OSA-SNa treatment. In addition, a higher NAD+/NADH ratio and glucose-6-phosphate dehydrogenase activity provided a reducing condition for yellow pigment biosynthesis. Gene expression analysis showed that the expression levels of the key genes for yellow pigment biosynthesis were significantly upregulated by OSA-SNa. This study provides an effective strategy to promote the production of WSMPs by microparticle-enhanced cultivation using OSA-SNa. KEY POINTS: • OSA-SNa addition facilitated the production of Monascus yellow pigments. • Mycelial morphology and membrane permeability were affected by OSA-SNa. • The key gene expression of yellow pigments was upregulated.


Assuntos
Monascus , Fermentação , Monascus/metabolismo , Pigmentos Biológicos/metabolismo , Sódio , Amido , Succinatos , Água
7.
Appl Microbiol Biotechnol ; 105(5): 1905-1912, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33576885

RESUMO

Monascus pigments (MPs) are widely used natural colorants in Asian countries. The problems of low extracellular red pigment (ERP) and high citrinin remain to be solved in Monascus pigment production. The effect of lanthanum(III) ion (LaCl3) on Monascus purpureus fermentation was investigated in this study. The yields of ERP and biomass respectively reached maxima of 124.10 U/mL and 33.10 g/L by adding 0.4 g/L La3+ on the second day in the total 8-day fermentation; simultaneously, citrinin was decreased by 59.93% and 38.14% in the extracellular and intracellular fractions, respectively. Reactive oxygen species (ROS) levels were obviously improved by La3+ treatment, while the activities of catalase (CAT) and superoxide dismutase (SOD) were increased compared with the control. The ratio of unsaturated/saturated fatty acids in mycelia was increased from 2.94 to 3.49, indicating that the permeability and fluidity of the cell membrane were enhanced under La3+ treatment. Gene expression analysis showed that the relative expression levels of Monascus pigment synthesis genes (pksPT, mppB, mppD, MpFasB2, and MpPKS5) were significantly upregulated by La3+ treatment, and in contrast, the relative expression levels of citrinin synthesis genes (ctnA, pksCT and mppC) were markedly downregulated. This work confirmed that LaCl3 possesses the potential to induce red pigment biosynthesis and inhibit citrinin production in M. purpureus fermentation. KEY POINTS: • La3+ induced red pigment and inhibited citrinin production in Monascus fermentation. • La3+ regulated genes expression up for Monascus pigment and down for citrinin. • La3+ increased the UFAs in cell membrane to enhance the permeability and fluidity.


Assuntos
Citrinina , Monascus , Ásia , Fermentação , Lantânio , Monascus/metabolismo , Pigmentos Biológicos/metabolismo
8.
Molecules ; 23(6)2018 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-29789494

RESUMO

To investigate the effects of fusel alcohols on the intoxicating degree of liquor products, formulated liquors (FLs) were prepared by blending 1-propanol, isobutanol, and isoamyl alcohol with ethanol, organic acids, and corresponding ethyl esters to simulate the formula of traditional Chinese liquors. The prepared FLs were submitted for evaluation of their intoxicating degree (ID). The results showed that the fusel alcohols had a biphasic effect on the IDs of the FLs, depending on the comprehensive coordination of the characteristic minor components. The importance of the suitable ratio of alcohols/acids/esters (RAAE) on the IDs was also revealed. Under an optimal ratio level, the fusel alcohols exhibited negligible effects on the IDs of the FLs. Moreover, the ratio of isoamyl alcohol to isobutanol (IA/IB) showed a strong positive correlation to the IDs of the FLs. This study lays a foundation for the potential application in producing low-ID liquor.


Assuntos
Bebidas Alcoólicas/toxicidade , Álcoois/química , Aminoácidos/química , Comportamento Animal/efeitos dos fármacos , Ésteres/química , Bebidas Alcoólicas/análise , Animais , Masculino , Camundongos , Distribuição Aleatória
9.
Sci Rep ; 6: 27205, 2016 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-27251222

RESUMO

Biohydrogen production has received widespread attention from researchers in industry and academic fields. Response surface methodology (RSM) was applied to evaluate the effects of several key variables in anaerobic fermentation of glucose with Clostridium butyrium, and achieved the highest production rate and yield of hydrogen. Highest H2 yield of 2.02 mol H2/mol-glucose was achieved from 24 h bottle fermentation of glucose at 35 °C, while the composition of medium was (g/L): 15.66 glucose, 6.04 yeast extract, 4 tryptone, 3 K2HPO4, 3 KH2PO4, 0.05 L-cysteine, 0.05 MgSO4·7H2O, 0.1 MnSO4·H2O and 0.3 FeSO4·7H2O, which was very different from that for cell growth. Sugarcane bagasse and Jatropha hulls were selected as typical tropical biomass wastes to produce sugars via a two-step acid hydrolysis for hydrogen production. Under the optimized fermentation conditions, H2 yield (mol H2/mol-total reducing sugar) was 2.15 for glucose, 2.06 for bagasse hydrolysate and 1.95 for Jatropha hull hydrolysate in a 3L fermenter for 24 h at 35 °C, with H2 purity of 49.7-64.34%. The results provide useful information and basic data for practical use of tropical plant wastes to produce hydrogen.


Assuntos
Biocombustíveis/microbiologia , Clostridium butyricum/crescimento & desenvolvimento , Hidrogênio/metabolismo , Biomassa , Reatores Biológicos/microbiologia , Clostridium butyricum/metabolismo , Fermentação
10.
Fa Yi Xue Za Zhi ; 29(3): 185-9, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24303760

RESUMO

To investigate the association of five SNPs (rs823083, rs708723, rs4951261, rs823076 and rs16856110) at the PARK16 locus with Parkinson's disease (PD), and to potentiate its forensic application. The genomic DNAs of 215 PD patients and 212 matched controls from the northern Han Chinese population were amplified in two independent PCR systems and subsequently genotyped by digestion with the three endonucleases (Hinf I, Nco I and Msp I ). The genetic parameters and association studies were carried out with SPSS 13.0, Haploview version 4.2 and PLINK 1.07 softwares. We detected accurately all genotypes in the five SNPs with multiplex PCR-RFLP and mismatched multiplex PCR-RFLP techniques. The genotypes of four SNPs, except for rs823083, were in Hardy-Weinberg equilibrium. The four SNPs, rs16856110, rs4951261, rs708723 and rs823076, which were in linkage equilibrium, should not be associated with PD (P-values ranging from 0.077 to 0.544). The SNPs investigated at the PARK16 locus were not found to be involved in PD-associated blocks in the northern Han Chinese population. The allele distributions of rs708723, rs4951261, rs823076 and rs16856110 in the northern Han Chinese population can be highly polymorphic, which can be applied to genetic analysis and forensic practices.


Assuntos
Predisposição Genética para Doença , Doença de Parkinson/genética , Polimorfismo de Nucleotídeo Único , Adulto , Idoso , Povo Asiático/etnologia , Povo Asiático/genética , Estudos de Casos e Controles , Feminino , Genética Forense , Frequência do Gene , Estudos de Associação Genética , Loci Gênicos , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição
11.
Bioresour Technol ; 140: 447-50, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23908993

RESUMO

Catalytic conversion of un-pretreated Jatropha oil with high-acid value (13.8 mg KOH/g) to biodiesel was studied in ionic liquids (ILs) with metal chlorides. Several commercial ILs were used to catalyze the esterification of oleic acid. It was found that 1-butyl-3-methylimidazolium tosylate {[BMIm][TS]} had high catalytic activity with 93% esterification rate for oleic acid at 140 °C but only 63.7% Jatropha biodiesel yield at 200 °C. When ZnCl2 was added to [BMIm][TS], a maximum Jatropha biodiesel yield of 92.5% was achieved at 180 °C. Addition of metal ions supplied Lewis acidic sites in ILs promoted both esterification and transestrification reactions. It was also found that the transition metal ions performed higher catalytic activity in transestrification than the ions of Group A. Mixture of [BMIm][TS] and ZnCl2 was easily separated from products for reuse to avoid producing pollutants.


Assuntos
Biocombustíveis , Biotecnologia/métodos , Líquidos Iônicos/farmacologia , Jatropha/química , Ácido Oleico/química , Óleos de Plantas/química , Cloretos/farmacologia , Esterificação/efeitos dos fármacos , Imidazóis/farmacologia , Jatropha/efeitos dos fármacos
12.
Zhonghua Zheng Xing Wai Ke Za Zhi ; 29(3): 197-201, 2013 May.
Artigo em Chinês | MEDLINE | ID: mdl-25069347

RESUMO

OBJECTIVE: To evaluate whether or not administration of folic acid and resveratrol have preventive effects on cleft palate formation as well as the comparison of the two drugs' s effects. METHODS: Pregnant mice were randomly divided into 9 groups, with 8 mice in each group. The TCDD group mice were dosed with TCDD 28 microg/kg body weight on gestation day 10 (GD 10) animals in folic acid group were respectively dosed with folic acid 15, 10, 5 mg/kg and TCDD 28 microg/kg; resveratrol treated mice were divided into 3 groups: resveratrol 50 mg/kg were orally administered for 6 consecutive days, from gestational day GD 8 to GD13 in resveratrol (GD8-13 ) group; resveratrol 50 mg/kg were orally administered for 6 consecutive days, from gestational day GD 8 to GD13, followed hy an oral administered with TCDD on GD10 in resveratrol (GD8-13) + TCDD group; resveratrol 50mg/kg and TCDD 28 microg/kg were used by gavage administration at GD10 in resveratrol (GD10) + TCDD group. Control mice were treated with the same volume of water for 6 consecutive days from GD8 to GD13 and were given a single dose of corn oil on GD10. The pregnant mice weight and embryos, the number of live, cleft palate, dead and resorption fetal mice were recorded on GD 17.5. The coronal sections of the fetal mice heads were prepared at GD 17.5 and observed by microscopy. RESULTS: Total frequency of clefts was 92.86% in TCDD group, 84.00% (15 mg), 73.08% (10 mg), 84.00% (5 mg) in folic acid + TCDD groups, 0% in resveratrol (GD10) group, 74.51% (GD10), 57.78% (GD8-13) in resveratrol + TCDD groups. The frequency of cleft was 0% in the control group. Compared with the control and the TCDD groups, there were significant differences in the number of live, dead and resorption fetal mice in TCCD + resveratrol (GD8-13) group (P < 0.05). No significant differences in embryonic weight, live fetuses weight, the number of live, dead and resorption fetal mice were found in the other groups (P > 0.05). CONCLUSION: Test dose of folic acid and resveratrol both had certain antagonistic effect on cleft palate in mice induced by TCDD, with folic acid 10 mg/kg, resveratrol 50 mg/kg GD8-13 doses having stronger antagonistic action. Effects of both the two drugs have no significant difference, but resveratrol (50 mg/kg, GD8-13) significantly affects the fetal mice's growth and development under TCDD exposure in utero.


Assuntos
Anormalidades Induzidas por Medicamentos/prevenção & controle , Fissura Palatina/prevenção & controle , Ácido Fólico/farmacologia , Dibenzodioxinas Policloradas/antagonistas & inibidores , Estilbenos/farmacologia , Teratógenos , Animais , Fissura Palatina/induzido quimicamente , Feminino , Feto , Ácido Fólico/administração & dosagem , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Gravidez , Distribuição Aleatória , Resveratrol , Estilbenos/administração & dosagem
13.
Biotechnol Biofuels ; 4(1): 53, 2011 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-22099703

RESUMO

BACKGROUND: Previous studies have shown that the crystalline structure of cellulose is negatively correlated with enzymatic digestibility, therefore, pretreatment is required to break down the highly ordered crystalline structure in cellulose, and to increase the porosity of its surface. In the present study, an organic electrolyte solution (OES) composed of an ionic liquid (1-allyl-3-methylimidazolium chloride ([AMIM]Cl)) and an organic solvent (dimethyl sulfoxide; DMSO) was prepared, and used to pretreat microcrystalline cellulose for subsequent enzymatic hydrolysis; to our knowledge, this is the first time that this method has been used. RESULTS: Microcrystalline cellulose (5 wt%) rapidly dispersed and then completely dissolved in an OES with a molar fraction of [AMIM]Cl per OES (χ [AMIM]Cl) of greater than or equal to 0.2 at 110°C within 10 minutes. The cellulose was regenerated from the OES by precipitation with hot water, and enzymatically hydrolyzed. As the χ [AMIM]Cl of the OES increased from 0.1 to 0.9, both the hydrolysis yield and initial hydrolysis rate of the regenerated cellulose also increased gradually. After treatment using OES with χ [AMIM]Cl of 0.7, the glucose yield (54.1%) was 7.2 times that of untreated cellulose. This promotion of hydrolysis yield was mainly due to the decrease in the degree of crystallinity (that is, the crystallinity index of cellulose I). CONCLUSIONS: An OES of [AMIM]Cl and DMSO with χ [AMIM]Cl of 0.7 was chosen for cellulose pretreatment because it dissolved cellulose rapidly to achieve a high glucose yield (54.1%), which was only slightly lower than the value (59.6%) obtained using pure [AMIM]Cl. OES pretreatment is a cost-effective and environmentally friendly technique for hydrolysis, because it 1) uses the less expensive OES instead of pure ionic liquids, 2) shortens dissolution time, 3) requires lower energy for stirring and transporting, and 4) is recyclable.

14.
Bioresour Technol ; 102(13): 6884-6, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21530245

RESUMO

Biodiesel and lactic acid from rapeseed oil was produced using sodium silicate as catalyst. The transesterification in the presence of the catalyst proceeded with a maximum yield of 99.6% under optimized conditions [3% (w/w) sodium silicate, methanol/oil molar ratio 9/1, reaction time 60 min, reaction temperature 60°C, and stirring rate 250 rpm]. After six consecutive transesterification reactions, the catalyst was collected and used for catalysis of the conversion of glycerol to lactic acid. A maximum yield of 80.5% was achieved when the reaction was carried out at a temperature of 300°C for 90 min. Thus, sodium silicate is an effective catalyst for transesterification and lactic acid production from the biodiesel by-product, glycerol.


Assuntos
Biocombustíveis/análise , Biotecnologia/métodos , Ácido Láctico/síntese química , Óleos de Plantas/química , Silicatos/química , Catálise , Ácidos Graxos Monoinsaturados , Glicerol/química , Óleo de Brassica napus , Temperatura , Fatores de Tempo , Água/química
15.
Bioresour Technol ; 102(11): 6469-72, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21420854

RESUMO

Catalytic conversion of un-pretreated Jatropha oil with high-acid value (13.8 mg KOH/g) to biodiesel was studied in ionic liquids (ILs) with metal chlorides. Several commercial ILs were used to catalyze the esterification of oleic acid. It was found that 1-butyl-3-methylimidazolium tosylate ([BMIm][CH(3)SO(3)]; a Brønsted acidic IL) had the highest catalytic activity with 93% esterification rate for oleic acid at 140°C but only 12% biodiesel yield at 120°C. When FeCl(3) was added to [BMIm][CH(3)SO(3)], a maximum biodiesel yield of 99.7% was achieved at 120°C. Because metal ions in ILs supplied Lewis acidic sites, and more of the sites could be provided by trivalent metallic ions than those of bivalent ones. It was also found that the catalytic activity with bivalent metallic ions increased with atomic radius. Mixture of [BMIm][CH(3)SO(3)] and FeCl(3) was easily separated from products for reuse to avoid producing pollutants.


Assuntos
Biocombustíveis/análise , Biotecnologia/métodos , Líquidos Iônicos/química , Jatropha/química , Ácido Oleico/química , Óleos de Plantas/química , Cloretos/química , Esterificação , Imidazóis/química , Metais/química
16.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 27(4): 473-6, 2010 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-20677162

RESUMO

OBJECTIVE: To reveal the sequence variations of the full coding region of the human alpha (1,beta/1,4) fucosyltransferase 5 gene (FUT5) in a Chinese Han population. METHODS: The whole coding region of the FUT5 gene was amplified and sequenced in a total of 30 unrelated Chinese Han individuals. The PCR products containing the nucleotide variants observed in the study were subcloned into plasmid pcDNA to determine all potential haplotypes in the investigated population. Genetic polymorphisms of C560T (rs778970) and C484A loci were further analyzed by polymerase chain reaction-restriction fragment length polymorphism(PCR-RLFP) method. RESULTS: In addition to seven previously reported base substitutions, two novel polymorphisms, namely C484A (Leu162Met) and T684C, were found in the coding region of the FUT5 gene in the 30 individuals. Seven haplotypes were identified by subcloning the variants into plasmid and subsequent DNA sequencing. The allele frequencies in the rs778970 locus in 160 Chinese Han individuals was 0.3031 for 560C and 0.6969 for 560T, while no polymorphism was detected in the C484A locus. CONCLUSION: The sequence of the coding region in the human FUT5 gene demonstrated high genetic diversity, and the allelic distribution of the rs778970 locus in the Chinese populations is polymorphic.


Assuntos
Povo Asiático/genética , Fucosiltransferases/genética , Variação Genética/genética , Haplótipos , Polimorfismo de Nucleotídeo Único , Grupos Populacionais/genética , Alelos , Povo Asiático/etnologia , Sequência de Bases , Frequência do Gene , Humanos , Fases de Leitura Aberta , Polimorfismo Genético , Análise de Sequência de DNA
17.
Fa Yi Xue Za Zhi ; 25(5): 345-7, 2009 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-20000042

RESUMO

OBJECTIVE: To investigate the sequence features of FUT2/01 locus and its polymorphic distribution in Chinese population, and to discuss its application potential in forensic medicine. METHODS: The alleles on FUT2/01 locus were amplified by PCR and then were sequenced. Furthermore, polymorphic distribution of the locus was analyzed by polyacrylamide gel electrophoresis. The genotypes were characterized with fluorescence labeling followed by automatic detection system. RESULTS: The sequencing results only showed the length differences which were determined by the tandem repeats variance of the core sequence. There were 9 alleles and 28 genotypes identified from 162 individuals. The discrimination power and excluding probability of paternity were 0.9639 and 0.6266, respectively. In addition, the locus could be genotyped by automatic analysis very well. CONCLUSION: The FUT2/01 locus exhibits high heterozygosity and individual identification power in Chinese Han population, and may be a valuable STR system for application in forensic medicine.


Assuntos
Fucosiltransferases/genética , Frequência do Gene , Polimorfismo Genético , Sequências de Repetição em Tandem/genética , Alelos , Povo Asiático , Sequência de Bases , China/etnologia , Eletroforese em Gel de Poliacrilamida , Genética Populacional , Genótipo , Humanos , Reação em Cadeia da Polimerase/métodos , Análise de Sequência de DNA
18.
Toxicol Ind Health ; 25(7): 473-8, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19783572

RESUMO

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) has been shown to induce cleft palate, in which the molecular etiology of the defect is poorly characterized. Recently, transforming growth factor-beta3 (TGF-beta3) has been indicated to play an essential role in the development of palatal shelves. In this developmental toxicity study, we investigated the effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on the expression of TGF-beta3 in fetal mice. Pregnant C57BL/6 mice were exposed to corn oil or TCDD (32 microg/kg/day 64 microg/kg/day, per os) at embryonic day 10 (ED10), a drastic inhibition of palatal shelves was induced. By using RT-PCR (reverse transcription-polymerase chain reaction) and Western blot, the expressions of TGF-beta3 was investigated. We found that the expression of TGF-beta3 was gradually up-regulated in TCDD-treated group. These results suggest that cleft palate can be induced by TCDD exposure, the modification of TGF-beta3 is related to its pathogenesis.


Assuntos
Fissura Palatina/induzido quimicamente , Fissura Palatina/metabolismo , Dibenzodioxinas Policloradas/toxicidade , Fator de Crescimento Transformador beta3/metabolismo , Anormalidades Induzidas por Medicamentos/metabolismo , Análise de Variância , Animais , Western Blotting , Feminino , Feto/efeitos dos fármacos , Imuno-Histoquímica , Camundongos , Gravidez , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Regulação para Cima
19.
Mycorrhiza ; 19(7): 461-467, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19404686

RESUMO

Tuber indicum is one of the most renowned commercialized fungi in China. Mycorrhizal investigations, however, have been carried out mainly with exotic trees. Up to now there is no detailed description of morphology of the mycorrhizae formed with the indigenous hosts of T. indicum. Containerized seedlings of two indigenous hosts of the fungus in southwestern China, Pinus armandii and Castanea mollissima, were inoculated with aqueous spore suspension of T. indicum in two kinds of substrates. Mycorrhizae began to form 4 months after inoculation and were harvested at 9 months. The contributing fungus of the mycorrhizae was confirmed to be T. indicum by morphological and ITS-rDNA sequence analyses. The morphology of emanating hyphae and epidermoid-like mantle appearance was similar to the mycorrhizae obtained with some European trees. The high morphological variation and the similarity to that of Tuber melanosporum makes it difficult to distinguish the mycorrhizae of the two species by morphology alone. The synthesis of mycorrhizae of T. indicum with its indigenous hosts will be of great significance for planned cultivation of the Asian black truffles.


Assuntos
Ascomicetos/crescimento & desenvolvimento , Fagaceae/microbiologia , Micorrizas/crescimento & desenvolvimento , Pinus/microbiologia , Ascomicetos/citologia , Ascomicetos/genética , Ascomicetos/isolamento & purificação , Micorrizas/citologia , Micorrizas/genética , Micorrizas/isolamento & purificação
20.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 26(5): 531-3, 2008 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-19007078

RESUMO

OBJECTIVE: To explore a method to repair nasal side mucosa of wide incomplete cleft palate and reduce the tension of wound by using oral mucosa flap in the top of fissure. METHODS: 27 cases of wide incomplete cleft palatal were included in the study. On the basis of two-flap palatoplasty, the triangular oral mucosa flap in the top of fissure was turned and sewed with side mucosa to repair nasal side mucosa of wide palatal cleft. RESULTS: Without postoperative active bleeding, airway obstruction and wound infection, 27 cases had been repaired satisfactorily by this procedure. 1-3 months followed up demonstrated that all the wounds healed well without wound dehiscence or fistulas and the scars in the palate were not severe. CONCLUSION: Using oral mucosa flap in the top of fissure to repair nasal side mucosa of wide palatal cleft can get a reduced tension and correspondingly increase the width of mucoperiosteal flaps so as to decrease incidence rate of palatal fistulas and reduce formation of scars.


Assuntos
Fissura Palatina , Mucosa Bucal , Feminino , Humanos , Mucosa Nasal , Procedimentos de Cirurgia Plástica , Retalhos Cirúrgicos
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