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1.
Microbiol Spectr ; 12(2): e0340523, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38230929

RESUMO

The white rot fungus Cerrena unicolor 87613 has been previously shown to be a promising resource in laccase production, an enzyme with significant biotechnological applications. Conventional methods face technical challenges in improving laccase activity. Attempts are still being made to develop novel approaches for further enhancing laccase activity. This study aimed to understand the regulation of laccase activity in C. unicolor 87613 for a better exploration of the novel approach. Transcriptomic and metabolomic analyses were performed to identify key genes and metabolites involved in extracellular laccase activity. The findings indicated a strong correlation between the glutathione metabolism pathway and laccase activity. Subsequently, experimental verifications were conducted by manipulating the pathway using chemical approaches. The additive reduced glutathione (GSH) dose-dependently repressed laccase activity, while the GSH inhibitors (APR-246) and reactive oxygen species (ROS) inducer (H2O2) enhanced laccase activity. Changes in GSH levels could determine the intracellular redox homeostasis in interaction with ROS and partially affect the expression level of laccase genes in C. unicolor 87613 in turn. In addition, GSH synthetase was found to mediate GSH abundance in a feedback loop. This study suggests that laccase activity is negatively influenced by GSH metabolism and provides a theoretical basis for a novel strategy to enhance laccase activity by reprogramming glutathione metabolism at a specific cultivation stage.IMPORTANCEThe production of laccase activity is limited by various conventional approaches, such as heterologous expression, strain screening, and optimization of incubation conditions. There is an urgent need for a new strategy to meet industrial requirements more effectively. In this study, we conducted a comprehensive analysis of the transcriptome and metabolome of Cerrena unicolor 87613. For the first time, we discovered a negative role played by reduced glutathione (GSH) and its metabolic pathway in influencing extracellular laccase activity. Furthermore, we identified a feedback loop involving GSH, GSH synthetase gene, and GSH synthetase within this metabolic pathway. These deductions were confirmed through experimental investigations. These findings not only advanced our understanding of laccase activity regulation in its natural producer but also provide a theoretical foundation for a strategy to enhance laccase activity by reprogramming glutathione metabolism at a specific cultivation stage.


Assuntos
Cebus , Lacase , Polyporales , Transcriptoma , Lacase/genética , Lacase/metabolismo , Espécies Reativas de Oxigênio , Peróxido de Hidrogênio , Perfilação da Expressão Gênica , Glutationa , Ligases/genética , Ligases/metabolismo
2.
Fungal Biol ; 127(1-2): 872-880, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36746559

RESUMO

Phenolic compounds are widely distributed in nature and industrial environment, and their detoxification or bioactive enhancement is of great value to environmental protection and industrial development. Laccases are multicopper oxidases that catalyse the oligo- or polymerisation of phenolic compounds. Identifying new laccase producers and investigating their application potential are of great importance. In this study, a white-rot fungus, Trametes hirsuta EZ1, with significantly high laccase productivity was isolated. The optimum conditions were studied for the maximum fermentation of extracellular laccase, which was achieved at 150 U/mL with a medium containing 10% strain EZ1, 7% maltodextrin, 1.5% peptone, and 0.5 mM Cu2+, and incubation at initial pH 6.0, 32 °C, and 180 rpm for nine days. Subsequently, a 70-kDa laccase was purified that showed activity over a wide range of temperature and pH, sensitivity to many metal ions and sodium dodecyl sulphate, and high tolerance to organic solvents. Purified laccase showed a significant unreported effect by catalysing catechol or ferulic acid into dimers, trimers, and tetramers or caffeic acid into dimers, trimers, tetramers, and pentamers. The oligomeric mixtures exhibited increased antioxidative capacity compared to that of each parent monomer, except for caffeic acid derivatives. Our study offers a novel strain source for laccase production and broadens its application in the enhancement of bioactive compounds.


Assuntos
Polyporaceae , Trametes , Lacase
3.
World J Pediatr ; 11(3): 245-9, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26041496

RESUMO

BACKGROUND: This study aimed to evaluate the clinical features of posterior reversible encephalopathy syndrome (PRES) in children. METHODS: The medical records of 31 patients from five medical centers who were diagnosed with PRES from 2001 to 2013 were retrospectively analyzed. In the 31 patients, 16 were males, and 15 females, with a median age of 7 years (3-12 years). Patients younger than 10 years accounted for 74.2% of the 31 patients. RESULTS: Seizure, the most common clinical sign, occurred in 29 of the 31 patients. Visual disturbances were also observed in 20 patients. Cerebral imaging abnormalities were bilateral and predominant in the parietal and occipital white matter. In this series, three patients died in the acute phase of PRES. One patient had resolution of neurologic presentation within one week, but no apparent improvement in radiological abnormalities was observed at eight months. One patient showed gradual recovery of both neurologic presentation and radiological abnormalities during follow-up at eight months. One patient developed long-term cortical blindness. All of the PRES patients with hematologic tumor had a worse prognosis than those without hematologic tumor. CONCLUSIONS: Seizure is a prevalent characteristic of children with PRES. Poor prognosis can be seen in PRES patients with hematologic tumor.


Assuntos
Neoplasias Hematológicas/diagnóstico , Neoplasias Hematológicas/epidemiologia , Síndrome da Leucoencefalopatia Posterior/diagnóstico , Síndrome da Leucoencefalopatia Posterior/epidemiologia , Convulsões/epidemiologia , Centros Médicos Acadêmicos , Anticonvulsivantes/uso terapêutico , Causas de Morte , Criança , Pré-Escolar , China , Estudos de Coortes , Comorbidade , Progressão da Doença , Feminino , Neoplasias Hematológicas/terapia , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Síndrome da Leucoencefalopatia Posterior/terapia , Valores de Referência , Estudos Retrospectivos , Medição de Risco , Convulsões/tratamento farmacológico , Convulsões/fisiopatologia , Índice de Gravidade de Doença , Análise de Sobrevida
4.
Expert Opin Pharmacother ; 13(12): 1695-705, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22716311

RESUMO

INTRODUCTION: Invasive fungal infection (IFI) is a serious problem due to difficulties in early diagnosis and high mortality. Different approaches are adopted for the treatment and management of IFI, including prophylactic, empiric, preemptive and directed strategies. AREAS COVERED: This paper reviews the type of pharmacotherapy used for antifungal prophylaxis in infants with extremely low birth weights, pediatric patients with cardiac disease, preterm neonates, pediatric oncology patients, adult cancer patients with neutropenia, adult patients with hematologic malignancy, hematopoietic stem-cell transplantation recipients, organ transplant recipients, HIV-infected patients, immunosuppressed patients treated with moderate or high doses of corticosteroids, and patients with invasive fusariosis, candidemia, invasive candidiasis, systemic mycoses and immunocompromised patients. EXPERT OPINION: Azole drugs are the drugs most often used in cost-effective antifungal prophylaxis of patients with conditions such as immunodeficiency and cancer, which render them highly susceptible to IFI. Fluconazole is the most outstanding example. However, there are many azoles with different pharmacological characteristics that the physician can choose from. Echinocandins have favorable characteristics that make them useful for treating Candida infections. Antibodies, or their engineered derivatives directed against cell-wall polysaccharides and glycopeptides, and some protein epitopes of Candida albicans, appear to be a promising novel approach for prophylaxis against Candida infection and deserve further in-depth investigations.


Assuntos
Antifúngicos/uso terapêutico , Micoses/prevenção & controle , Azóis/uso terapêutico , Humanos , Hospedeiro Imunocomprometido
5.
Zhongguo Gu Shang ; 24(3): 189-91, 2011 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-21485561

RESUMO

OBJECTIVE: To study the clinical efficacy of the endobutton in the treatment of acute acromioclavicular joint dislocation by reconstructing coracoclavicular ligaments. METHODS: From October 2008 to January 2010,12 patients with acute acromioclavicular joint dislocation were immobilized with the endobutton. All the patients had the dislocations of or above type III according to Rockwood classification. Among the patients, 9 patients were male and 3 patients were female, with an average age of 55 years (ranged from 31 to 83 years). Eight patients had injuries in the left, and 4 patients in the right. Four patients had accompanied injuries of rib fractures, 2 patients had brain injuries,and 1 patient had femoral fracture. Seven patients were injured by traffic accident, 4 patients were injured by falling down,and 1 patient was sports injuries. All the patients had pain and tenderness at the shoulder, positive piano sign, and shoulder confined activity. The duration from injury to operation ranged from 2 days to 10 days (averaged 6 days). The therapeutic effects were evaluated by Karlsson criteria based on range of motion of acromioclavicular joint, subjective feeling,and postoperative X-ray. RESULTS: All the patients were followed up, and the duration ranged from 4 months to 19 months (averaged 11 months). The motion of the shoulder joint recovered to normal about 15 to 35 days after operation. There were no displacement, dislocation and redislocation occurred. All the patients got A degree results according to Karlsson criteria. CONCLUSION: Reconstruction of coracoclavicular ligament by using the endobutton to treat acute acromioclavicular dislocation of or above type III is a perfect method with advantage of rigid fixation, micro-injury, and early functional exercise.


Assuntos
Articulação Acromioclavicular/lesões , Fixadores Externos , Luxações Articulares/cirurgia , Procedimentos Ortopédicos/instrumentação , Articulação Acromioclavicular/diagnóstico por imagem , Articulação Acromioclavicular/fisiopatologia , Articulação Acromioclavicular/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Luxações Articulares/diagnóstico por imagem , Luxações Articulares/fisiopatologia , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X , Resultado do Tratamento
6.
Appl Microbiol Biotechnol ; 90(1): 59-68, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21336922

RESUMO

This review covers the biosynthesis of glyceollin and its biological activities including antiproliferative/antitumor action (toward B16 melanoma cells, LNCaP prostate cancer cells, and BG-1 ovarian cancer cells), anti-estrogenic action (through estrogen receptors α- and ß-), antibacterial action (toward Erwinia carotovora, Escherichia coli, Bradyrhizobium japonicum, Sinorhizobium fredii ), antinematode activity, and antifungal activity (toward Fusarium solani, Phakospora pachyrhizi, Diaporthe phaseolorum, Macrophomina phaseolina, Sclerotina sclerotiorum, Phytophthora sojae, Cercospora sojina, Phialophora gregata, and Rhizoctonia solani). Other activities include insulinotropic action and attenuation of vascular contractions in rat aorta.


Assuntos
Anti-Infecciosos/farmacologia , Antineoplásicos/farmacologia , Glycine max/química , Pterocarpanos/farmacologia , Sesquiterpenos/farmacologia , Animais , Anti-Infecciosos/metabolismo , Antineoplásicos/metabolismo , Tratamento Farmacológico , Humanos , Pterocarpanos/biossíntese , Sesquiterpenos/metabolismo , Glycine max/metabolismo , Fitoalexinas
7.
Zhong Yao Cai ; 31(1): 11-4, 2008 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-18589739

RESUMO

To elucidate the influence of processing conditions on pilose antlers therapic effects, the protein composition and activities were compared on three kinds of pilose antler processed by lyophilization, freezing and traditional short-time heating, respectively. The concentration of the water soluble protein in freeze-dried pilose antler was 126.54 mg/g (Folin-Phenol assay), which was 13.1 times higher than that of heating processed antler. These proteins distributed widely in SDS-PAGE electrophoresis and the protein band between 50.0 kDa approximately 60.0 kDa achieved the highest concentration. The water extract of freeze-dried antler promoted the proliferation and IGF-I secretion of rat osteogenic-like cell UMR-106 by 245.25% ( MTT assay) and 66.36 ng/ml, which was respectively 2.2 times and 1.2 times of those of heating processed antler. The same candidate inhibited the growth of human hepatic carcinoma cell BEL-7402 by the highest rate of 47.64% , which was 1.4 times of heating processed antler. The activities of frozen fresh pilose antler were lower than those of its freeze-dried counterpart, but were much higher than those of heating processed antler. The results indicated that lyophilization help to remain the activity of pilose antlers proteins as much as possible and improve its efficacy.


Assuntos
Chifres de Veado/química , Proliferação de Células/efeitos dos fármacos , Materia Medica/farmacologia , Proteínas/análise , Tecnologia Farmacêutica/métodos , Animais , Linhagem Celular Tumoral , Cervos , Liofilização/métodos , Temperatura Alta , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Masculino , Materia Medica/isolamento & purificação , Osteoblastos/metabolismo , Osteoblastos/patologia , Osteossarcoma/metabolismo , Osteossarcoma/patologia , Proteínas/isolamento & purificação , Albumina Sérica/análise , Albumina Sérica/isolamento & purificação
8.
Zhongguo Zhong Yao Za Zhi ; 30(11): 851-5, 2005 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-16110870

RESUMO

OBJECTIVE: The activity of deer serum albumin on proliferation of rat osteogenic-like cells UMR-106 and the IGF-I secretion were investigated in order to elucidate pilose antler's bone-strengthening mechanism. METHOD: Deer serum albumin was isolated from freeze-dry pilose antler powder extract. The methods were Sephacryl S-200HR gel filtration, POROS 20QE ion-exchange and TSK G3000SW chromatographies. The effect of deer serum albumin on proliferatio of UMR-106 cells was assaied by MTT, and the secretion of IGF-I of UMR-106 cells was assaied by RIA. RESULT: Deer serum albumin, with the molecular weight of 56.3 kDa, significantly increased the proliferation rate of the osteoblast-like UMR-106 cell and IGF-I secretion. When concentration of deer serum albumin reached 0.149 microg x mL(-1), UMR-106 cell proliferation rate was 241.03% and IGF-I secretion was 66.89 ng x mL(-1). CONCLUSION: The concentration of deer serum albumin, from 14.9 ng x mL(-1) to 14.90 microg x mL(-1), significantly increased the proliferation rate of the osteoblast-like UMR-106 cell and IGF- I secretion.


Assuntos
Chifres de Veado , Proliferação de Células/efeitos dos fármacos , Materia Medica/farmacologia , Osteossarcoma/patologia , Albumina Sérica/farmacologia , Animais , Chifres de Veado/química , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Cervos , Fator de Crescimento Insulin-Like I/metabolismo , Materia Medica/isolamento & purificação , Osteoblastos/metabolismo , Osteoblastos/patologia , Ratos , Albumina Sérica/isolamento & purificação
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