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1.
Phys Rev Lett ; 126(24): 242301, 2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34213947

RESUMO

Using combined data from the Relativistic Heavy Ion and Large Hadron Colliders, we constrain the shear and bulk viscosities of quark-gluon plasma (QGP) at temperatures of ∼150-350 MeV. We use Bayesian inference to translate experimental and theoretical uncertainties into probabilistic constraints for the viscosities. With Bayesian model averaging we propagate an estimate of the model uncertainty generated by the transition from hydrodynamics to hadron transport in the plasma's final evolution stage, providing the most reliable phenomenological constraints to date on the QGP viscosities.

2.
Nanotechnology ; 32(4): 042003, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33155576

RESUMO

This roadmap on Nanotechnology for Catalysis and Solar Energy Conversion focuses on the application of nanotechnology in addressing the current challenges of energy conversion: 'high efficiency, stability, safety, and the potential for low-cost/scalable manufacturing' to quote from the contributed article by Nathan Lewis. This roadmap focuses on solar-to-fuel conversion, solar water splitting, solar photovoltaics and bio-catalysis. It includes dye-sensitized solar cells (DSSCs), perovskite solar cells, and organic photovoltaics. Smart engineering of colloidal quantum materials and nanostructured electrodes will improve solar-to-fuel conversion efficiency, as described in the articles by Waiskopf and Banin and Meyer. Semiconductor nanoparticles will also improve solar energy conversion efficiency, as discussed by Boschloo et al in their article on DSSCs. Perovskite solar cells have advanced rapidly in recent years, including new ideas on 2D and 3D hybrid halide perovskites, as described by Spanopoulos et al 'Next generation' solar cells using multiple exciton generation (MEG) from hot carriers, described in the article by Nozik and Beard, could lead to remarkable improvement in photovoltaic efficiency by using quantization effects in semiconductor nanostructures (quantum dots, wires or wells). These challenges will not be met without simultaneous improvement in nanoscale characterization methods. Terahertz spectroscopy, discussed in the article by Milot et al is one example of a method that is overcoming the difficulties associated with nanoscale materials characterization by avoiding electrical contacts to nanoparticles, allowing characterization during device operation, and enabling characterization of a single nanoparticle. Besides experimental advances, computational science is also meeting the challenges of nanomaterials synthesis. The article by Kohlstedt and Schatz discusses the computational frameworks being used to predict structure-property relationships in materials and devices, including machine learning methods, with an emphasis on organic photovoltaics. The contribution by Megarity and Armstrong presents the 'electrochemical leaf' for improvements in electrochemistry and beyond. In addition, biohybrid approaches can take advantage of efficient and specific enzyme catalysts. These articles present the nanoscience and technology at the forefront of renewable energy development that will have significant benefits to society.

3.
J Appl Microbiol ; 131(2): 647-657, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33119148

RESUMO

AIMS: This study aimed to investigate the antibacterial ability and action mechanism of dithiocyano-methane against Aeromonas hydrophila, so as to provide a reference for its application in farm disinfection. METHODS AND RESULTS: After exposing the bacteria to dithiocyano-methane, the minimum inhibitory concentration (MIC), minimum bactericide concentration (MBC), activities of alkaline phosphatase, aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase and electric conductivity in bacterial suspensions were determined, transmission electron microscope images on cellular structure and SDS-PAGE profile of bacterial proteins were analysed and the expression of genes related to the above experimental observations was confirmed by real-time quantitative PCR. The MIC and MBC of dithiocyano-methane against three tested strains was 1·46 and 2·93 mg l-1 respectively. The results showed that dithiocyano-methane significantly damaged bacterial cell structure, inhibited the biosynthesis of bacterial proteins and changed the integrity and permeability of bacterial cell wall and cell membrane. CONCLUSIONS: Dithiocyano-methane showed remarkable antibacterial ability against three tested strains, indicating it is a potential effective bactericidal agent for preventing animal diseases resulted from Aer. hydrophila. SIGNIFICANCE AND IMPACT OF THE STUDY: To our best knowledge, this is the first report to examine the antibacterial ability and action mechanism of dithiocyano-methane against bacteria. The results demonstrate the great potential of dithiocyano-methane as a disinfectant against Aer. hydrophila in settings such as aquaculture ponds and livestock farms.


Assuntos
Antibacterianos , Desinfetantes/farmacologia , Desinfecção , Metano , Aeromonas hydrophila/efeitos dos fármacos , Animais , Antibacterianos/farmacologia , Fazendas , Metano/farmacologia , Testes de Sensibilidade Microbiana
4.
J Appl Microbiol ; 128(5): 1301-1311, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31898381

RESUMO

AIM: To effectively make high-quality silage in hot and humid area. METHODS AND RESULTS: The natural lactic acid bacteria (LAB) strains CZ149, XH358, XH753 and XH761 isolated from corn and Napier grass were screened by the potential of low pH growth and high lactic acid production, and their effect on silage quality, aerobic stability and aflatoxin B1 production of whole-crop corn was also studied in Sichuan, China. Four selected strains were Gram-positive and catalase-negative, rod-shaped strains that are able to grow at pH 3·5 and at 45°C. Strains CZ149, XH358, XH753 and XH761 were identified as Lactobacillus plantarum, L. salivarius, L. rhamnosus and L. paracasei, respectively. After 60 days of fermentation, all LAB strains showed no significant relationship with the quality of corn silage, whereas the lowest aflatoxin B1 and lactic-to-acetic ratio were detected in strain XH753-treated silage. Strain CZ149-treated silage showed worse aerobic stability and higher aflatoxin B1 concentration than control, whereas strain XH753-treated silage had better aerobic stability and lowest aflatoxin B1 concentration after aerobic exposure in hot and humid condition for 5 days. CONCLUSIONS: The three L. plantarum strains used in this study are not suitable as inoculants for local whole-crop corn silage, whereas L. rhamnosus 753 could prolong the aerobic stability and inhibit the accumulation of aflatoxin B1 at hot and humid condition. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides new information of LAB inoculants for corn silage in hot and humid areas. Especially, a screened strain of Lactobacillus rhamnosus 753 can be used as a candidate strains to make high-quality silage in tropical and subtropical areas.


Assuntos
Aflatoxina B1/análise , Lactobacillales/isolamento & purificação , Lactobacillales/fisiologia , Silagem/microbiologia , China , Fermentação , Temperatura Alta , Concentração de Íons de Hidrogênio , Ácido Láctico/metabolismo , Lactobacillales/classificação , Lactobacillales/metabolismo , Pennisetum/microbiologia , Silagem/análise , Especificidade da Espécie , Zea mays/microbiologia
5.
J Eur Acad Dermatol Venereol ; 34(4): 862-872, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31856347

RESUMO

BACKGROUND: Chancre self-healing is an important clinical feature in the early stages of syphilis infection. Wound healing may involve an important mechanism by the migration of fibroblasts filling the injured lesion. However, the specific mechanism underlying this process is still unknown. OBJECTIVES: We aimed to analyse the role of Tp0136 in the migration of fibroblasts and the related mechanism. METHODS: The migration ability of fibroblasts was detected by a wound-healing assay. RT-PCR and ELISA detected the expression of MCP-1, IL-6 and MMP-9. TLR4 expression was detected by RT-PCR. The protein levels of CCR2 and relevant signalling pathway molecules were measured by Western blotting. RESULTS: Tp0136 significantly promoted fibroblast migration. Subsequently, the levels of MCP-1 and its receptor CCR2 were increased in this process. The migration of fibroblasts was significantly inhibited by an anti-MCP-1 neutralizing antibody or CCR2 inhibitors. Furthermore, studies demonstrated that Tp0136 could activate the ERK/JNK/PI3K/NF-κB signalling pathways through TLR4 activity and that signalling pathways inhibitors could weaken MCP-1 secretion and fibroblast migration. CONCLUSIONS: These findings demonstrate that Tp0136 promotes the migration of fibroblasts by inducing MCP-1/CCR2 expression through signalling involving the TLR4, ERK, JNK, PI3K and NF-κB signalling pathways, which could contribute to the mechanism of chancre self-healing in syphilis.


Assuntos
Quimiocina CCL2/metabolismo , Fibroblastos/metabolismo , Receptores CCR2/metabolismo , Proteínas Recombinantes/metabolismo , Receptor 4 Toll-Like/metabolismo , Treponema pallidum , Cicatrização/fisiologia , Western Blotting , Movimento Celular , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Sífilis/patologia
6.
J Dairy Sci ; 103(1): 191-200, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31677830

RESUMO

The volatile flavor substances in traditional fermented yak milk samples collected from 5 ecoregions (A: coniferous forests and grasslands of the Qilian Qingdong Mountains; B: alpine grasslands surrounding the lakes in the Qiangtang Plateau; C: alpine shrubs and meadows of the Guoluo-Nagqu Highlands; D: coniferous forests along the alpine valley in East Tibet; E: shrubs and grasslands along the alpine valley in South Tibet) of the Qinghai-Tibetan plateau were comparatively analyzed. The relative percentage composition of volatile flavor substances varied among the different ecoregions. In samples collected from region E, more than 50% of the volatile flavor compounds were esters comprising mainly n-butyl acetate, butyl butyrate, and ethyl octanoate, and a considerable proportion of acetoin was found in samples from regions B and E. Greater proportions of 2-heptanone and 2-nonanone were observed in samples collected from regions A, C, and D compared with regions B and E.


Assuntos
Bovinos/metabolismo , Aromatizantes/química , Cetonas/química , Leite/química , Animais , Meio Ambiente , Fermentação , Alimentos Fermentados , Tibet , Volatilização
7.
J Appl Microbiol ; 126(1): 40-48, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30223299

RESUMO

AIMS: Characteristics of a strain Pediococcus pentosaceus Q6 isolated from Elymus nutans growing on the Tibetan plateau and its effects on E. nutans silage fermentation stored at low temperature were investigated. METHODS AND RESULTS: Sugar fermentation pattern and growth profiles of the strain Q6 and its reference strain APP were characterized. The strain Q6 and APP were inoculated to E. nutans at ensiling respectively; and ensiled at different temperatures (10, 15 and 25°C) for 30, 60 and 90 days. The results indicated that Q6 could grow at pH 3·0 and at 4°C. In contrast to APP, Q6 could ferment mannitol, saccharose, sorbitol and rhamnose. Lower pH in Q6-treated silages fermented for 60 days at 10 and 15°C was found compared with the control and APP-treated groups. For the silages that were stored at 10 or 15°C, the greatest lactic acid content were detected in Q6-inoculated silages ensiled for 30 and 60 days respectively. There were no differences in pH and lactic acid content between Q6- and APP-treated silages ensiled at 10 and 15°C for 90 days respectively. CONCLUSIONS: Inoculation of the strain P. pentosaceus Q6 could improve fermentation quality of ensiled E. nutans at the early stage of ensiling stored at low temperature (10 or 15°C). SIGNIFICANCE AND IMPACT OF THE STUDY: The selection of P. pentosaceus inoculants for improving silage quality at low temperature, which provides a candidate strain to make high-quality silage in regions with frigid climate.


Assuntos
Elymus/microbiologia , Pediococcus pentosaceus/isolamento & purificação , Silagem/análise , Temperatura Baixa , Elymus/crescimento & desenvolvimento , Fermentação , Ácido Láctico/metabolismo , Manitol/metabolismo , Pediococcus pentosaceus/classificação , Pediococcus pentosaceus/genética , Silagem/microbiologia , Sorbitol/metabolismo , Sacarose/metabolismo , Temperatura , Tibet
8.
Allergy ; 73(1): 221-229, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28658503

RESUMO

BACKGROUND: Proton pump inhibitors (PPIs) have been known to induce type I hypersensitivity reactions. However, severe delayed-type hypersensitivity reactions (DHR) induced by PPI, such as Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), or drug rash with eosinophilia and systemic symptoms (DRESS), are rarely reported. We conducted a study of a large series of PPI-related DHR, followed up their tolerability to alternative anti-ulcer agents, and investigated the T-cell reactivity to PPI in PPI-related DHR patients. METHODS: We retrospectively analyzed patients with PPI-related DHR from multiple medical centers in Taiwan during the study period January 2003 to April 2016. We analyzed the causative PPI, clinical manifestations, organ involvement, treatment, and complications. We also followed up the potential risk of cross-hypersensitivity or tolerability to other PPI after their hypersensitivity episodes. Drug lymphocyte activation test (LAT) was conducted by measuring granulysin and interferon-γ to confirm the causalities. RESULTS: There were 69 cases of PPI-related DHR, including SJS/TEN (n=27) and DRESS (n=10). The LAT by measuring granulysin showed a sensitivity of 59.3% and specificity of 96.4%. Esomeprazole was the most commonly involved in PPI-related DHR (51%). Thirteen patients allergic to one kind of PPI could tolerate other structurally different PPI without cross-hypersensitivity reactions, whereas three patients developed cross-hypersensitivity reactions to alternative structurally similar PPI. The cross-reactivity to structurally similar PPI was also observed in LAT assay. CONCLUSIONS: PPIs have the potential to induce life-threatening DHR. In patients when PPI is necessary for treatment, switching to structurally different alternatives should be considered.


Assuntos
Hipersensibilidade a Drogas/imunologia , Hipersensibilidade Tardia/imunologia , Inibidores da Bomba de Prótons/efeitos adversos , Reações Cruzadas/imunologia , Citocinas/metabolismo , Hipersensibilidade a Drogas/diagnóstico , Hipersensibilidade a Drogas/tratamento farmacológico , Hipersensibilidade a Drogas/mortalidade , Feminino , Humanos , Hipersensibilidade Tardia/diagnóstico , Hipersensibilidade Tardia/tratamento farmacológico , Hipersensibilidade Tardia/mortalidade , Tolerância Imunológica , Ativação Linfocitária/imunologia , Masculino , Inibidores da Bomba de Prótons/química , Testes Cutâneos , Esteroides/administração & dosagem , Esteroides/uso terapêutico , Avaliação de Sintomas , Linfócitos T/imunologia , Linfócitos T/metabolismo
9.
J Dairy Sci ; 100(11): 8958-8966, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28918135

RESUMO

We studied the effects on alfalfa preservation and chemical composition of the addition of different levels of malic acid and citric acid at ensiling as well as the utilization efficiency of these 2 organic acids after fermentation. Alfalfa was harvested at early bloom stage. After wilting to a dry matter content of approximately 40%, the alfalfa was chopped into 1- to 2-cm pieces for ensiling. Four levels (0, 0.1, 0.5, and 1% of fresh weight) of malic acid or citric acid were applied to chopped alfalfa at ensiling with 4 replicates for each treatment, and the treated alfalfa forages were ensiled for 60 d in vacuum-sealed polyethylene bags (dimensions: 200 mm × 300 mm) packed with 200 to 230 g of fresh alfalfa per mini silo and an initial density of 0.534 g/cm3. The application of malic or citric acids at ensiling for 60 d led to lower silage pH than was observed in the control silage (0% of malic or citric acids). Application of the 2 organic acids led to higher lactic acid concentration in alfalfa silage than in the control silage except with the application rate of 1% of fresh weight. Silages treated with both organic acids had lower nonprotein nitrogen concentrations than the control silages, and the nonprotein nitrogen concentrations in ensiled forages decreased with the increase in malic or citric acid application rates. The application of the 2 organic acid additives led to lower saturated fatty acid proportions and higher polyunsaturated fatty acid proportions in ensiled alfalfa than in the control silage. The amount of malic and citric acids degraded during ensiling of alfalfa was 1.45 and 0.63 g, respectively. At the application rate of 0.5% of fresh weight, residues of malic acid and citric acid in alfalfa silage were 11.1 and 13.6 g/kg of dry matter. These results indicate that including malic or citric acids at the ensiling of alfalfa effectively improved silage fermentation quality, limited proteolysis, improved fatty acid composition of the ensiled forage, and could provide animals with additional feed additives proven to promote animal performance. However, when the application rate of both organic acids reached 1%, the concentration of lactic acid in silages decreased notably. Additionally, 0.5 and 1% application rates also increased the yeast count in ensiled alfalfa.


Assuntos
Ácido Cítrico/farmacologia , Malatos/farmacologia , Medicago sativa , Silagem , Fermentação/efeitos dos fármacos , Ácido Láctico/metabolismo , Medicago sativa/química , Silagem/análise
10.
Genet Mol Res ; 15(2)2016 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-27173234

RESUMO

Oenanthe L. is a taxonomically complex genus, several species of which have long been used as vegetables and traditional medicines in East Asia. In order to clarify the taxonomic status of Oenanthe accessions and provide baseline data for the sustainable use of its genetic resources, we examined sequence variations in the internal transcribed spacer (ITS) region of Oenanthe accessions collected from a wide geographical area in China and its neighboring countries. For comparison, ITS sequences in GenBank for almost all currently reported species of Oenanthe were also included in our analyses. Both phylogenetic tree construction methods (Bayesian inference and maximum likelihood) revealed that the accessions tended to cluster into two groups, which were closely related to O. mildbraedii and O. sarmentosa. However, these two species have never been recorded in China or its neighboring countries. Therefore, it seems probable that in our sampled locations, Oenanthe accessions have been given an incorrect name, such as O. javanica. Future studies should carefully check the morphological characteristics of other Oenanthe species and sequence their ITS regions in order to clarify the taxonomic status of the genus.


Assuntos
DNA Espaçador Ribossômico/genética , Oenanthe/genética , Filogenia , Animais , China , Classificação , Variação Genética , Oenanthe/classificação , Análise de Sequência de DNA , Especificidade da Espécie
11.
Genet Mol Res ; 12(1): 223-9, 2013 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-23408408

RESUMO

Nelumbo nucifera is widely used as food, as an ornamental, in medicine, and as packing material; it is also reported to have anti-HIV effects and antioxidant capacity. We sought an improved method for extracting high-quality total RNA from different tissues of N. nucifera. Four methods for RNA extraction were assessed for their ability to recover high-quality RNA applicable for evaluation of polyphenol oxidase (PPO) gene expression profiles. The recovery and quality of the RNA obtained from five different tissues by the best CTAB-LiCl method were evaluated through UV light absorbance. Both A(260)/A(280) and A(260)/A(230) absorbance ratios were more than 2.0; the yield ranged from 59.87 to 163.75 µg/g fresh weight. The brightness of the 28S band was approximately twice that of 18S; the latter was also considered as high-quality RNA. The PPO gene fragment (606 bp) was successfully amplified by RT-PCR, demonstrating the integrity of the isolated RNA. The relative expression levels of the PPO gene based on RT-PCR in five tissues of lotus were: rhizome buds (2.66), young leaves (2.42), fresh cut rhizome (2.02), petals (1.80), and petiole (1.65), using housekeeping gene ß-actin as an internal control. We concluded that the total RNA isolated by this protocol is of sufficient quality for molecular applications.


Assuntos
Nelumbo/química , Nelumbo/genética , Extratos Vegetais/química , RNA de Plantas/química , RNA de Plantas/genética , Actinas/química , Actinas/genética , Catecol Oxidase/genética , Extratos Vegetais/genética
13.
J Viral Hepat ; 18(9): 637-45, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21794025

RESUMO

Hepatitis B virus (HBV) DNA levels and liver histological necroinflammation grades are correlated with the antiviral efficacy. It is necessary to clarify the relationship between HBV replication levels apportioned by the same hepatic parenchyma cell volume and severity of liver histological necroinflammation grades in both hepatitis B e antigen (HBeAg)-positive and HBeAg-negative chronic hepatitis B. The serum HBV DNA levels apportioned by the same hepatic parenchyma cell volume were compared between HBeAg-positive and HBeAg-negative chronic hepatitis B as well as among liver histological necroinflammation grades 1, 2, 3 and 4, respectively. There were no differences in the serum HBV DNA levels between HBeAg-positive and HBeAg-negative chronic hepatitis B as well as among liver histological necroinflammation grades 1, 2, 3 and 4. However, there were differences in the serum HBV DNA levels apportioned by the same hepatic parenchyma cell volume among liver histological necroinflammation grades 1, 2, 3 and 4 in both HBeAg-positive and HBeAg-negative chronic hepatitis B, respectively. There were no differences in HBV DNA levels with the same liver histological necroinflammation grade activated by HBV wild-type and variant strains. After the differences in hepatic parenchyma cell volume for HBV replication of the same liver histological necroinflammation grade accompanied by different hepatic fibrosis stages were adjusted, the serum HBV DNA level apportioned by the same hepatic parenchyma cell volume was correlated with the severity of liver histological necroinflammation grade.


Assuntos
DNA Viral/sangue , Vírus da Hepatite B/patogenicidade , Hepatite B Crônica/patologia , Cirrose Hepática/patologia , Fígado/patologia , Adulto , Alanina Transaminase/sangue , Análise de Variância , Biópsia , Tamanho Celular , Feminino , Antígenos E da Hepatite B/sangue , Vírus da Hepatite B/fisiologia , Hepatite B Crônica/virologia , Humanos , Inflamação/patologia , Inflamação/virologia , Fígado/virologia , Cirrose Hepática/virologia , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Replicação Viral , Adulto Jovem
14.
Artigo em Inglês | MEDLINE | ID: mdl-21929466

RESUMO

In the present study, the cytotoxic effects and toxicological mechanism of six polybrominated diphenyl ethers (PBDEs) metabolites (3-OH-BDE47, 3-MeO-BDE47, 5-OH-BDE47, 5-MeO-BDE47, 6-OH-BDE85 and 6-MeO-BDE85) on L02 cells were explored by investigating the cell viability, apoptosis, lactic dehydrogenase (LDH) leakage, and oxidative stress response. The results showed that these metabolites could inhibit cell proliferation and induce apoptosis, among which 6-OH-BDE85 had the highest efficiency. LDH leakage test also showed that 6-OH-BDE85 had the strongest ability to cause LDH release. The reactive oxygen species (ROS) levels in 6-OH-BDE85- and 3-OH-BDE47-treated groups were significantly elevated in a dose-dependent manner. After treatment for 24 h, four BDE47 metabolites (3-OH-BDE47, 3-MeO-BDE47, 5-OH-BDE47, and 5-MeO-BDE47) induced an increase in superoxide dismutase (SOD) activity and decrease in glutathione (GSH) level, whereas 6-OH-BDE85 led to a decrease in both SOD activity and GSH level. These effects disappeared after continued culturing for another 24 h. In conclusion, these PBDE metabolites, especially 6-OH-BDE85, showed cytotoxicity on L02 cells, which was at least partially related to the oxidative stress level.


Assuntos
Éteres Difenil Halogenados/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Glutationa/metabolismo , Éteres Difenil Halogenados/química , Humanos , Bifenil Polibromatos/química , Bifenil Polibromatos/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo
15.
Sci Rep ; 8(1): 357, 2018 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-29321642

RESUMO

Using gas chromatography mass spectrometry and the PacBio single molecule with real-time sequencing technology (SMRT), we analyzed the detailed metabolomic profiles and microbial community dynamics involved in ensiled Medicago sativa (alfalfa) inoculated without or with the homofermenter Lactobacillus plantarum or heterofermenter Lactobacillus buchneri. Our results revealed that 280 substances and 102 different metabolites were present in ensiled alfalfa. Inoculation of L. buchneri led to remarkable up-accumulation in concentrations of 4-aminobutyric acid, some free amino acids, and polyols in ensiled alfalfa, whereas considerable down-accumulation in cadaverine and succinic acid were observed in L. plantarum-inoculated silages. Completely different microbial flora and their successions during ensiling were observed in the control and two types of inoculant-treated silages. Inoculation of the L. plantarum or L. buchneri alters the microbial composition dynamics of the ensiled forage in very different manners. Our study demonstrates that metabolomic profiling analysis provides a deep insight in metabolites in silage. Moreover, the PacBio SMRT method revealed the microbial composition and its succession during the ensiling process at the species level. This provides information regarding the microbial processes underlying silage formation and may contribute to target-based regulation methods to achieve high-quality silage production.


Assuntos
Lactobacillus/fisiologia , Medicago sativa/metabolismo , Medicago sativa/microbiologia , Metaboloma , Metabolômica , Biodiversidade , Fermentação , Lactobacillus/classificação , Lactobacillus plantarum/fisiologia , Metabolômica/métodos , Microbiota , Silagem , Simbiose
16.
Leukemia ; 17(3): 541-6, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12646942

RESUMO

We evaluated the incidence, timing, and consequences of urolithiasis in children with acute lymphoblastic leukemia (ALL). A total of 20 patients with urolithiasis were identified from 2095 patients with ALL treated at St Jude Children's Research Hospital on consecutive protocols between 1968 and 1998. For remission induction therapy, all patients received daily prednisone; continuation chemotherapy regimens differed by protocol with some including pulses of prednisone or dexamethasone and others no glucocorticoid. Patients with urolithiasis were older at diagnosis of ALL than those without urolithiasis (median age, 7.5 vs 5.0 years; P=0.03) and less likely to be black (P=0.03) than white or Hispanic, but sex and treatment era did not differ. Presenting symptoms included abdominal or flank pain, hematuria, and dysuria. All stones analyzed biochemically were calcium stones. The incidence of urolithiasis after completion of therapy was 1.8 per 10 000 person-years. Compared to this baseline rate, the relative risk of urolithiasis was 45 (P<0.01) during induction therapy, 22 (P<0.01) during continuation therapy with glucocorticoids, and 5.1 (P>0.05) during continuation therapy without glucocorticoids. Urolithiasis occurred 4.5 times more often during continuation treatment with glucocorticoids than without (P<0.05). Seven patients (35%) had recurrent urolithiasis. Patients with ALL are at risk of developing calcium renal stones during chemotherapy, especially when a glucocorticoid is included.


Assuntos
Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Cálculos Urinários/induzido quimicamente , Adolescente , Adulto , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Doenças Ósseas Metabólicas/tratamento farmacológico , Criança , Pré-Escolar , Feminino , Glucocorticoides/efeitos adversos , Glucocorticoides/uso terapêutico , Humanos , Incidência , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Indução de Remissão/métodos , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Cálculos Urinários/química , Cálculos Urinários/etiologia
17.
Biomaterials ; 18(17): 1169-74, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9259514

RESUMO

A wovenable skin substitute (Sacchachitin) made from the residue of the fruiting body of Ganoderma tsugae was developed in this study. Chemical analysis revealed that the treated residue was a copolymer of beta-1,3-glucan (ca 60%) and N-acetylglucosamine (ca 40%) with a filamental structure of mycelia form, as demonstrated by both optical and scanning electron microscopy. The pulp-like white residue was then woven into thin, porous sheets 7.0 cm in diameter and 0.1-0.2 mm in thickness by filtration and lyophilized for use as a skin substitute. The wound area produced by dissecting rat skin of full thickness was found to almost completely heal on the side covered with Sacchachitin, whereas the control side covered with cotton gauge was around 6.0 cm2 on the 28th day. Furthermore, the wound healing effects of the chitin sheet from crab shell (Beschitin) and Sacchachitin were not found to be significantly different.


Assuntos
Acetilglucosamina/metabolismo , Basidiomycota/metabolismo , Materiais Biocompatíveis/metabolismo , Quitina/metabolismo , Glucanos/metabolismo , Pele Artificial/normas , beta-Glucanas , Acetilglucosamina/análise , Acetilglucosamina/farmacologia , Animais , Materiais Biocompatíveis/uso terapêutico , Quitina/química , Quitina/farmacologia , Cromatografia Gasosa , Cromatografia em Camada Fina , Glucanos/química , Glucanos/farmacologia , Glucose/análise , Microscopia Eletrônica de Varredura , Nitrogênio/análise , Polissacarídeos/química , Polissacarídeos/metabolismo , Polissacarídeos/farmacologia , Porosidade , Ratos , Ratos Wistar , Cicatrização/efeitos dos fármacos
18.
J Gastroenterol ; 31(6): 818-22, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9027645

RESUMO

Hepatitis E virus (HEV) infection is sporadic in the Guangzhou city southern China. However, the evaluation of antibodies to HEV during consecutive time periods after infection has not been reported. We utilized enzyme immunosorbent assay (ELISA) to defect IgM and IgG anti-HEV in consecutive serum specimens from patients with acute hepatitis E and compared that data with detection rates of IgM and IgG anti-HAV in patients with acute hepatitis A. IgM anti-HEV can be detected as early as 4 days after onset of disease symptoms in some patients. The detection rate of IgM anti-HEV is significantly higher in specimens collected within 4 weeks (95%) of onset than in those specimens collected 4 to 18 weeks after onset (67.6%) (P < 0.005). IgM anti-HEV had a similar pattern to IgM anti-HAV and can be used as a marker of acute HEV infection. In contrast with IgG anti-HAV, 56.8% of the specimens did not contain detectable levels of IgG anti-HEV (P < 0.005). One should be cautioned against making a diagnosis of HEV infection solely by the currently available assays for IgG anti-HEV. In conclusion, IgM anti-HEV can be used as a reliable and sensitive marker for recent HEV infection, but serum specimens should be collected within 4 weeks after onset of symptoms to avoid false-negative results. In contrast, we should be aware of the failure to develop IgG anti-HEV in some patients. These patients carry the risk of reinfection.


Assuntos
Anticorpos Anti-Hepatite/análise , Vírus da Hepatite E/imunologia , Hepatite E/imunologia , Imunoglobulina G/análise , Imunoglobulina M/análise , Doença Aguda , Adulto , Biomarcadores , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Recidiva , Estudos Retrospectivos , Fatores de Risco
19.
Eur J Pharm Biopharm ; 51(3): 215-9, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11343885

RESUMO

The sustained-release effects of codried excipient of modified Ganoderma (treated with alkaline solution) and microcrystalline cellulose at different ratios were examined using acetaminophen (ACT) as a model drug. Results demonstrate that the crushing strength of most ACT tablets made with codried powder at all ratios increased as compaction force increased; but a rapid decline was observed when compression force exceeded 2 tons. Drug release from tablets compressed at 0.5 ton increased as modified Ganoderma fiber content increased. But when the compression force exceeded 1 ton, the release rate was not influenced by the compaction force or the increasing content of Ganoderma fiber. However, the dissolution of ACT from these tablets could be sustained for longer than 24 h. The extent of drug release was shown to increase with increasing amounts of modified Ganoderma in the codried excipient. The addition of disintegrants could further accelerate the drug release from the tablet. Drug release was also dependent upon the amount and kind of disintegrant used. The influence was in the following order: primojel>crospovidone>starch 1500.


Assuntos
Acetaminofen/química , Celulose/química , Medicamentos de Ervas Chinesas/química , Excipientes/química , Analgésicos não Narcóticos/química , Química Farmacêutica , Preparações de Ação Retardada , Microscopia Eletrônica de Varredura , Reishi , Solubilidade , Fatores de Tempo
20.
Can J Ophthalmol ; 25(3): 159-63, 1990 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2163281

RESUMO

We report the light and electron microscopic findings for two lesions from two patients who died of complications of familial adenomatous polyposis. In the first case microscopy of a small (100 to 200 mu), uniformly dark lesion (the commonest type seen in this condition) showed enlarged retinal pigment epithelial cells with an increased number of pigment granules. This is consistent with the term "hypertrophy of the retinal pigment epithelium", currently used to describe these lesions. In the second case we sectioned a larger (1000 to 1500 mu), oval, grey lesion from the posterior pole. The pigment epithelium was normal, but between it and outer retina was an unusual choristoma consisting largely of myelinated axons and astrocytes.


Assuntos
Polipose Adenomatosa do Colo/complicações , Retina/ultraestrutura , Doenças Retinianas/patologia , Adulto , Fundo de Olho , Humanos , Masculino , Pessoa de Meia-Idade , Células Fotorreceptoras/patologia , Epitélio Pigmentado Ocular/ultraestrutura , Doenças Retinianas/congênito , Doenças Retinianas/etiologia
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