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1.
Medicine (Baltimore) ; 103(21): e38203, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38788018

RESUMO

To analyze the correlation between Balthazar CT grading and contrast-enhanced CT necrosis volume and attenuation value and prognosis of patients with acute necrotizing pancreatitis. Ninety-two patients with acute necrotizing pancreatitis who were treated in the hospital were selected between June 2019 and June 2021, and they were divided into the poor prognosis group and the good prognosis group according to the clinical prognosis at 6 months of follow-up. Balthazar CT, contrast-enhanced CT necrosis volume, and attenuation value were compared between the 2 groups. Multivariate logistic regression analysis was used to analyze the influencing factors. Receiver operating characteristic curve was adopted to analyze the predictive value. Among the 92 participants, there were 28 cases with good prognosis (30.43%) and 64 cases with poor prognosis (69.57%). The Acute Physiology and Chronic Health Evaluation II score, C-reactive protein, urea nitrogen, Balthazar CT, necrotic volume, and average attenuation value of the poor prognosis group were significantly higher than those of the good prognosis group (all P values <.05). The results of the multivariate logistic analysis showed that Balthazar CT grade, necrotic volume, and average attenuation value were independent risk factors for poor prognosis in patients with acute necrotizing pancreatitis (all P values <.05). The area under the curve of Balthazar CT grade, necrotic volume, average attenuation value, and the joint detection in predicting the prognosis of patients with acute necrotizing pancreatitis were 0.765, 0.624, 0.764, and 0.861, respectively. The Balthazar CT grading, necrosis volume, and average attenuation value are significantly higher among patients with acute necrotizing pancreatitis complicated with poor prognosis, and they are also independent risk factors for poor prognosis in patients with acute necrotizing pancreatitis, and can help clinically predict the prognosis of patients with acute necrotizing pancreatitis, and the combined detection has better application effects.


Assuntos
Pancreatite Necrosante Aguda , Tomografia Computadorizada por Raios X , Humanos , Pancreatite Necrosante Aguda/diagnóstico por imagem , Pancreatite Necrosante Aguda/mortalidade , Pancreatite Necrosante Aguda/patologia , Masculino , Feminino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X/métodos , Prognóstico , Adulto , Necrose/diagnóstico por imagem , Curva ROC , Idoso , Índice de Gravidade de Doença , Estudos Retrospectivos , Fatores de Risco , Meios de Contraste , Valor Preditivo dos Testes
2.
Int Orthop ; 48(7): 1849-1858, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38627330

RESUMO

PURPOSE: To introduce anterior peri-sacroiliac joint osteotomy (APSJO) through the lateral-rectus approach (LRA) for treating pelvic fracture malunion and nonunion, and to evaluate the safety, feasibility, and potential effectiveness. METHODS: Data of 15 patients with pelvic fracture malunion and nonunion who underwent treatment by APSJO were selected and analyzed. The reduction quality was assessed using the Mears and Velyvis criteria, while the pre-operative and post-operative function was revealed by the Majeed scoring system. The British Medical Research Council (BMRC) grading system was recruited for the evaluation of lumbosacral plexus function. RESULTS: The average operative duration was 264.00 ± 86.75 min, while the intra-operative blood loss was 2000 (600, 3000) mL. Anatomical reduction was complete in three cases, satisfactory in ten cases, and unsatisfactory in two cases. Among the seven patients with lumbosacral plexus injury, the pre-operative Majeed grades were good in two cases, fair in two cases, and poor in three cases, while the post-operative Majeed grades were excellent in three cases, good in three cases, and fair in one case. Muscle strength recovered to M5 in two cases, M4 in three cases, and showed no recovery in two cases. The pre-operative Majeed grades were good in five cases, fair in two cases, and poor in one case of the series without lumbosacral plexus injury, while the post-operative Majeed grades were excellent in seven cases and good in one case. CONCLUSION: APSJO through LRA may be a feasible strategy for treating pelvic fracture malunion and nonunion with promising application.


Assuntos
Fraturas Mal-Unidas , Fraturas não Consolidadas , Osteotomia , Ossos Pélvicos , Articulação Sacroilíaca , Humanos , Adulto , Feminino , Masculino , Osteotomia/métodos , Fraturas Mal-Unidas/cirurgia , Fraturas não Consolidadas/cirurgia , Ossos Pélvicos/lesões , Ossos Pélvicos/cirurgia , Pessoa de Meia-Idade , Articulação Sacroilíaca/cirurgia , Articulação Sacroilíaca/lesões , Resultado do Tratamento , Adulto Jovem , Fixação Interna de Fraturas/métodos , Fixação Interna de Fraturas/instrumentação , Fraturas Ósseas/cirurgia , Adolescente
3.
Aesthetic Plast Surg ; 47(5): 2001-2010, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37389649

RESUMO

BACKGROUND: Using M-shaped cartilage grafts is a new method for the correction of short nose deformity with good effect for Asians. Although the basic approach to M-shaped cartilage surgery is well understood, there is a great deal of uncertainty when plastic surgeons perform the procedure, and still a lack of standard guidance on the specific details. METHODS: In this study, the authors used finite element analysis to explore and compare postoperative cartilage stability of different fixing methods, different suturing positions, and different sizes of M-shaped cartilage. The authors applied a 0.01 N load to a 1 cm2 area of the nasal tip to simulate nasal tip palpation and compared the maximum deformations of different groups, which were used to make stability judgments. RESULTS: The maximum deformation of the model was the least when the M-shaped cartilage was fixed medially to the septal cartilage and laterally to the outer crura of the lower lateral cartilage. At the same time, the maximum deformation was the least when the M-shaped cartilage was sutured to the middle of the nasal septal cartilage. Besides, the length of M-shaped cartilage was preferably around 30 mm, while its width was not worthy of being overly concerned. CONCLUSIONS: For optimal postoperative stability of Asian short nose correction, the M-shaped cartilage should be sutured and fixed medially to the middle of the septal cartilage and laterally to the lateral crura of the lower lateral cartilage, and the length of the M-shaped cartilage should be controlled at around 30 mm. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

4.
Sci Rep ; 12(1): 20716, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36456681

RESUMO

Long-term continuous monoculture cropping of tobacco leads to high incidence of tobacco bacterial wilt (TBW) caused by Ralstonia solanacearum, which threatening world tobacco production and causing great economy loss. In this study, a safe and effective way to control TBW by microbial degradation of phenolic allelochemicals (PAs) was explored. Eleven kinds of PAs were identified from continuous tobacco cropping soil. These PAs exhibited various effects on the growth, chemotaxis and biofilm formation of R. solanacearum. Then we isolated eight strains of Bacillus, one strain of Brucella, one strain of Enterobacter and one strain of Stenotrophomonas capable of degrading these PAs. The results of degradation assay showed that these isolated strains could degrade PAs both in culture solutions and soil. Besides, the incidence of TBW caused by R. solanacearum and deteriorated by PAs were significantly decreased by treating with these degrading strains. Furthermore, six out of eleven isolated strains were combined to degrade all the identified PAs and ultimately sharply reduced the incidence of TBW by 61.44% in pot experiment. In addition, the combined degrading bacteria could promote the plant growth and defense response. This study will provide a promising strategy for TBW control in tobacco production.


Assuntos
Nicotiana , Feromônios , Uso de Tabaco , Fenóis , Solo , Enterobacter
5.
Orthop Surg ; 14(12): 3233-3241, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36259635

RESUMO

OBJECTIVE: There has been a controversy in the surgical approach for delayed acetabular fracture. The objective of the present study is to investigate the feasibility, surgical techniques, safety, and efficacy of periacetabular osteotomy using the single lateral-rectus approach (LRA) for the surgical treatment of delayed acetabular fracture. METHODS: The retrospective study included 22 patients (16 males and six females, with an average age of 45 years) with delayed acetabular fractures from June 2012 to June 2019. For all cases, periacetabular osteotomy was performed through the single LRA. Fracture classification, mechanism of injury, associated injury, time to surgery, operation time, intraoperative blood loss, and complications were recorded and analyzed. The quality of the reduction was assessed based on Matta radiographic criteria. Potential impact factors affecting the quality of reduction were analyzed. Functional outcome was evaluated at the final follow-up according to a modified Mere D'Aubigne-Postel scoring system for each patient. RESULTS: All patients were followed up for at least 12 months. The duration of surgery was 140 min on average (110-205 min) and the mean intraoperative blood loss was 1250 ml (500-2100 ml). According to Matta radiographic criteria, the accuracy of reduction was "anatomical" in seven patients, "imperfect" in 11 patients, and "poor" in four patients, with an excellent and good rate of 81.8%. The time to surgery in poor reduction group was significantly longer than anatomical or imperfect reduction group (p < 0.05). All the acetabular fractures united after 8-12 weeks. The average modified Merle D'Aubigne-Postel score evaluated at the final follow-up was 14.6 (6-18), and the clinical outcomes were rated as excellent in six patients, good in 10 patients, fair in four patients, and poor in two patients, with an excellent and good rate of 72.7%. There were two cases of osteonecrosis of the femoral head (9%). No other complication was found for all cases. CONCLUSION: The LRA is an effective and minimally invasive approach in the treatment of delayed acetabular fractures excluding posterior wall fracture and posterior dislocation.


Assuntos
Perda Sanguínea Cirúrgica , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos
6.
Biomed Pharmacother ; 146: 112570, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34959114

RESUMO

We developed an innovative method to include quercetin into alpha-calcium sulphate hemihydrate/nano-hydroxyapatite (α-CSH/n-HA), to prepare a novel quercetin-containing α-CSH/n-HA composite (Q-α-CSH/n-HA). The physicochemical properties, and ability of Q-α-CSH/n-HA to promote cell proliferation, migration, and osteogenic differentiation of bone marrow stem cells (BMSCs) in vitro were examined. Further, the potential of Q-α-CSH/n-HA to promote bone defect repair was studied using a Sprague-Dawley rat model of critical tibial defects. Imaging was conducted by radiography and micro-CT, and bone defect repairs were observed by histopathological staining. Addition of quercetin clearly increased the porosity of the degraded composite, which elevated the cell proliferation rate, migration ability, osteogenesis differentiation, and mineralisation of BMSCs. Further, quercetin-containing composite increased the expression levels of OSX, RUNX2, OCN, ALP, BMP-2, OPN, BSP, SMAD2, and TGF-ß in BMSCs, while it downregulated TNF-α. X-ray and micro-CT imaging showed that the quercetin-containing composite significantly enhanced bone defect repair and new bone in formation. Haematoxylin and eosin, Goldner, and Safranin O staining also showed that quercetin significantly increased new bone generation and promoted composite degradation and absorption. Moreover, immunofluorescence assay revealed that quercetin significantly increased the number of RUNX2/OSX/OCN-positive cells. Overall, our data demonstrate that Q-α-CSH/n-HA has excellent biocompatibility, bone conductivity, and osteo-induction performance in vitro and mediates enhanced overall repair effects and bone reconstruction in vivo, indicating that it is a promising artificial bone graft to promote bone regeneration.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Sulfato de Cálcio/farmacologia , Osteogênese/efeitos dos fármacos , Quercetina/farmacologia , Tíbia/efeitos dos fármacos , Animais , Técnicas de Cultura de Células , Diferenciação Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Durapatita/química , Masculino , Ratos , Ratos Sprague-Dawley , Células-Tronco/efeitos dos fármacos
7.
Mater Sci Eng C Mater Biol Appl ; 131: 112496, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34857282

RESUMO

To improve the osteoinductivity, antibacterial activity, and clinical application of calcium sulfate hemihydrate (CSH), carboxymethyl chitosan zinc (CMCS-Zn) and α-CSH were prepared using different mass ratios. The setting time and injectability of the CMCS-Zn/α-CSH composite were increased with increasing CMCS-Zn content. After adding different amounts of CMCS-Zn to α-CSH, the fine lamellar structure of CMCS-Zn was found by scanning electron microscopy (SEM), which is evenly distributed in the matrix of α-CSH. With the increase of CMCS-Zn, the pores on the surface gradually increased. After mixing CMCS-Zn and α-CSH, no new phase was measured by X-ray diffraction (XRD) and Fourier transform (FTIR) spectroscopy. The degradation rate of CMCS-Zn/α-CSH decreased with increasing CMCS-Zn content, and the pH was stable during the degradation process. The release of Zn2+ increased with increasing CMCS-Zn content, while the release of Ca2+ decreased. Extracts of CMCS-Zn/α-CSH composites up-regulated the osteoinduction and migration of rat bone marrow stem cells. The antibacterial ability of CMCS-Zn/α-CSH was evaluated as a function of CMCS-Zn content. In the rat bone defect model, 5% CMCS-Zn/α-CSH group revealed a higher volume and density of trabeculae by micro-CT 8 weeks after the operation. Therefore, CMCS-Zn/α-CSH was demonstrated to be an adjustable, degradable, substitute biomaterial (with osteogenesis-promoting effects) for use in bone defects, which also has antibacterial activity that can suppress bone infection.


Assuntos
Sulfato de Cálcio , Quitosana , Animais , Materiais Biocompatíveis/farmacologia , Osteogênese , Ratos , Zinco
8.
ACS Omega ; 6(14): 9537-9548, 2021 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-33869934

RESUMO

Diosgenin is used widely to synthesize steroidal hormone drugs in the pharmaceutical industry. The conventional diosgenin production process, direct acid hydrolysis of the root of Dioscorea zingiberensis C. H. Wright (DZW), causes large amounts of wastewater and severe environmental pollution. To develop a clean and effective method, the endophytic fungus Fusarium sp. CPCC 400226 was screened for the first time for the microbial biotransformation of DZW in submerged fermentation (SmF). Statistical design and response surface methodology (RSM) were implemented to develop the diosgenin production process using the Fusarium strains. The environmental variables that significantly affected diosgenin yield were determined by the two-level Plackett-Burman design (PBD) with nine factors. PBD indicates that the fermentation period, culture temperature, and antifoam reagent addition are the most influential variables. These three variables were further optimized using the response surface design (RSD). A quadratic model was then built by the central composite design (CCD) to study the impact of interaction and quadratic effect on diosgenin yield. The values of the coefficient of determination for the PBD and CCD models were all over 0.95. P-values for both models were 0.0024 and <0.001, with F-values of ∼414 and ∼2215, respectively. The predicted results showed that a maximum diosgenin yield of 2.22% could be obtained with a fermentation period of 11.89 days, a culture temperature of 30.17 °C, and an antifoam reagent addition of 0.20%. The experimental value was 2.24%, which was in great agreement with predicted value. As a result, over 80% of the steroidal saponins in DZW were converted into diosgenin, presenting a ∼3-fold increase in diosgenin yield. For the first time, we report the SmF of a Fusarium strain used to produce diosgenin through the microbial biotransformation of DZW. A practical diosgenin production process was established for the first time for Fusarium strains. This bioprocess is acid-free and wastewater-free, providing a promising environmentally friendly alternative to diosgenin production in industrial applications. The information provided in the current study may be applicable to produce diosgenin in SmF by other endophytic fungi and lays a solid foundation for endophytic fungi to produce natural products.

9.
Pharmaceuticals (Basel) ; 14(5)2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33919111

RESUMO

Steroidal saponins are widely used as starting precursors and medical intermediates for the semi-/total-synthesis of hundreds of steroidal drugs. One such steroidal saponin is diosgenin, which has attracted significant attention due to the huge market demand in the pharmaceutical industry. Due to water waste and severe environmental pollution, the traditional diosgenin production process based on direct acid hydrolysis is no longer used. In this study, to develop a submerged fermentation (SmF) medium for clean diosgenin production via efficient microbial biocatalysis, the Box-Behnken design (BBD) in combination with the Plackett-Burman design (PBD) was used to determine the medium compositions for Fusarium strains. Three components (wheat bran, phosphate, and Tween-80) were determined as significant factors by the PBD. Using the BBD, the three significant factors were further optimized, and the optimum values were determined for maximal diosgenin production. With 21.16 g/L of wheat bran, 9.60 g/L of phosphate, and 1.97 g/L of Tween-80, the diosgenin yield was 2.28%, i.e., 3.17 mg/L/h. The experimental values agreed with the predicted values, representing a significant increase in diosgenin production compared to its production using the basic SmF medium. For the first time, we reported the development of a new medium for Fusarium strains to produce diosgenin via microbial biocatalysis of the root of Dioscorea zingiberensis C. H. Wright (DZW). A simple-composition, low-cost, and high-efficiency medium was developed for the first time for the SmF of Fusarium strains. The medium is considered useful for large-scale SmF and may be applicable to other fungi. This study lays a solid foundation for diosgenin production in an acid-free and wastewater-free way. It may also provide fundamental support for producing other value-added products via microbial biocatalysis of low-value materials by endophytic fungi.

10.
Front Microbiol ; 11: 1988, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32973717

RESUMO

Traditional diosgenin manufacturing process has led to serious environmental contamination and wastewater. Clean processes are needed that can alternate the diosgenin production. The ß-glucosidase FBG1, cloned from Fusarium sp. CPCC 400709, can biotransform trillin and produce diosgenin. In this study, Pichia pastoris production of recombinant FBG1 was implemented to investigate various conventional methanol induction strategies, mainly including DO-stat (constant induction DO), µ-stat (constant exponential feeding rate) and m-stat (constant methanol concentration). The new co-stat strategy combining µ-stat and m-stat strategies was then developed for enhanced FBG1 production during fed-batch high-cell density fermentation on methanol. The fermentation process was characterized with respect to cell growth, methanol consumption, FBG1 production and methanol metabolism. It was found that large amounts of formaldehyde were released by the enhanced dissimilation pathway when the co-stat strategy was implemented, and therefore the energy generation was enhanced because of improved methanol metabolism. Using co-stat feeding, the highest volumetric activity reached ∼89 × 104 U/L, with the maximum specific activity of ∼90 × 102 U/g. After 108 h induction, the highest volumetric production reached ∼403 mg/L, which was ∼91, 154, and 183 mg/L higher than the maximal production obtained at m-stat, µ-stat, and DO-stat strategies, respectively. FBG1 is the first P. pastoris produced recombinant enzyme for diosgenin production through the biotransformation of trillin. Moreover, this newly developed co-stat induction strategy represents the highest expression of FBG1 in P. pastoris, and the strategy can be used to produce FBG1 from similar Pichia strains harboring Fbg1 gene, which lays solid foundation for clean and sustainable production of diosgenin. The current work provides unique information on cell growth, substrate metabolism and protein biosynthesis for enhanced ß-glucosidase production using a P. pastoris strain under controlled fermentation conditions. This information may be applicable for expression of similar proteins from P. pastoris strains.

11.
J Biomater Appl ; 35(1): 97-107, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32233720

RESUMO

Fabrication of osteoconductive scaffold with osteoinductive capability and appropriate resorption rate is of great significance for treating bone defects. To achieve this aim, strontium-substituted calcium sulfate hemihydrate (Sr-CSH) and hydroxyapatite (HA) were mixed to develop a novel composite. Sr-CSH containing 5% and 10% strontium was mixed with HA at the weight ratio of 6:4, respectively. Female Sprague-Dawley rats underwent bone defect surgery in left tibia were randomly assigned to three different treatment groups filled with CSH/HA, 5% and 10% Sr-CSH/HA. Micro-CT analysis showed increased new bone formation in 10% Sr-CSH/HA group compared to CSH/HA group. In addition, histological analysis showed large amounts of chondrocytes and osteoblasts within the pores of Sr-CSH/HA composites as a result of the CSH resorption. Further, CFU-F assay demonstrated the increased amount of bone marrow mesenchymal stromal cells (BMSCs) colonies in 10% Sr-CSH/HA group. In primary BMSCs, extraction from Sr-CSH/HA composite significantly increased the migration of cells, up-regulated the expression of osteoblastic marker genes, and increased the area of mineralized nodules. Together, Sr-CSH/HA may promote bone formation by recruiting and stimulating osteogenic differentiation of BMSCs. Therefore, this composite may be proposed as an ideal substitute to repair bone defects.


Assuntos
Regeneração Óssea , Sulfato de Cálcio/química , Hidroxiapatitas/química , Células-Tronco Mesenquimais/citologia , Estrôncio/química , Alicerces Teciduais/química , Animais , Regeneração Óssea/efeitos dos fármacos , Sulfato de Cálcio/farmacologia , Proliferação de Células/efeitos dos fármacos , Feminino , Hidroxiapatitas/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Ratos Sprague-Dawley , Estrôncio/farmacologia
12.
Mol Med Rep ; 20(4): 3555-3564, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31432182

RESUMO

Calcium phosphate­based bone substitutes have been widely used for bone repair, augmentation and reconstruction in bone implant surgery. While some of these substitutes have shown excellent biological efficacy, there remains a need to improve the performance of the current calcium phosphate­based bone substitutes. Strontium ions (Sr) can promote new osteogenesis, inhibit osteoclast formation and increase osteoconductivity. However, the therapeutic effect and mechanism of strontium­containing α­calcium sulfate hemihydrate (Sr­CaS) remains unclear. The present study created bone injuries in rats and treated the injuries with Sr­CaS. Then Cell Counting Kit­8, soft agar colony formation, flow cytometry, Transwell and Alizarin Red staining assays were performed to assess the bone cells for their proliferation, growth, apoptosis, invasion, and osteogenic differentiation abilities. The bone reconstructive states were measured by the microCT method, hematoxylin and eosin staining and Masson staining. Bone­related factors were analyzed by the reverse transcription­quantitative PCR assay; transforming growth factor (TGF)­ß, mothers against decapentaplegic homolog (Smad)2/3 and ß­catenin expression was measured by western blot analysis and osteocalcin (OCN) expression was assessed by immunohistochemistry. Sr­CaS did not significantly affect the proliferation and apoptosis of bone marrow stem cells (BMSCs), but did accelerate the migration and osteogenic differentiation of BMSCs in vitro. Sr­CaS promoted bone repair and significantly increased the values for bone mineral density, bone volume fraction, and trabecular thickness, but decreased trabecular spacing in vivo in a concentration­-dependent manner. In addition, Sr­CaS dramatically upregulated the expression levels of genes associated with osteogenic differentiation (Runt­related transcription factor 2, Osterix, ALP, OCN and bone sialoprotein) both in vitro and in vivo. Sr­CaS also increased Smad2/3, TGF­ß and phosphorylated­ß­catenin protein expression in vitro and in vivo. These results indicated that materials that contain 5 or 10% Sr can improve bone defects by regulating the TGF­ß/Smad signaling pathway.


Assuntos
Substitutos Ósseos/uso terapêutico , Sulfato de Cálcio/uso terapêutico , Osteogênese/efeitos dos fármacos , Proteínas Smad/metabolismo , Estrôncio/uso terapêutico , Fator de Crescimento Transformador beta/metabolismo , Animais , Osso e Ossos/lesões , Células Cultivadas , Masculino , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
14.
Appl Microbiol Biotechnol ; 102(13): 5519-5532, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29725718

RESUMO

In this study, endophytic fungi were isolated from Dioscorea zingiberensis C.H. Wright (DZW), and a novel clean process to prepare diosgenin from DZW was developed. A total of 123 strains of endophytic fungi were isolated from different plant tissues of DZW. Among them, the strain Fusarium sp. (CPCC 400709) showed the best activity of hydrolyzing steroidal saponins in DZW into diosgenin. Thus, this strain was used to prepare diosgenin from DZW by solid-state fermentation. The fermentation parameters were optimized using response surface methodology, and a high yield of diosgenin (2.16%) was obtained at 14.5% ammonium sulfate, an inoculum size of 12.3%, and 22 days of fermentation. Furthermore, the highest diosgenin yield (2.79%) was obtained by co-fermentation with Fusarium sp. (CPCC 400709) and Curvularia lunata (CPCC 400737), which was 98.9% of that obtained by ß-glucosidase pretreated acid hydrolysis (2.82%). This process is acid-free and wastewater-free, and shows promise as an effective and clean way to prepare diosgenin for use in industrial applications from DZW.


Assuntos
Dioscorea/microbiologia , Diosgenina/metabolismo , Fermentação , Fusarium/isolamento & purificação , Fusarium/metabolismo , Microbiologia Industrial , Hidrólise , Saponinas/metabolismo
16.
Extremophiles ; 17(5): 757-65, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23818107

RESUMO

The fungal communities associated with three bryophytes species (the liverwort Barbilophozia hatcheri, the mosses Chorisodontium aciphyllum and Sanionia uncinata) in the Fildes Region, King George Island, maritime Antarctica, were studied using clone library analysis. Fungal communities showed low diversity; the 680 clones belonged to 93 OTUs. Of these, 78 belonged to the phylum Ascomycota, 13 to the phylum Basidiomycota, 1 to the phylum Zygomycota, and 1 to an unknown phylum. Among the OTUs, the most common orders in the Ascomycota were Helotiales (42 OTUs) and Chaetothyriales (14 OTUs) and the most common orders in the Basidiomycota were Sebacinales (3 OTUs) and Platygloeales (3 OTUs). Most OTUs clustered within clades that contained phylotypes identified from samples in Antarctic or Arctic ecosystems or from bryophytes in other ecosystems. In addition, we found that host-related factor may shape the fungal communities associated with bryophytes in this region. This is the first systematic study of the fungal community in Antarctic bryophytes to be performed using culture-independent method and the results may improve understanding of the endophytic fungal evolution and ecology in the Antarctic ecosystem.


Assuntos
Biodiversidade , Briófitas/microbiologia , Fungos/classificação , Regiões Antárticas , Ecossistema , Fungos/genética , Fungos/isolamento & purificação , Genes Fúngicos , Filogenia , RNA Ribossômico/genética
17.
Sensors (Basel) ; 8(9): 5649-5660, 2008 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-27873834

RESUMO

An electrochemical DNA biosensor for the detection of NOS gene sequences from genetically modified organisms (GMOs) is presented in this paper. Single-stranded DNA (ssDNA) was covalently attached through the carboxylate ester formed by the 3'- hydroxy end of the DNA with the carboxyl of a mercaptoacetic acid self-assembled monolayer-modified gold electrode using N-hydroxysuccinimide (NHS) and N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride (EDC) as linkers. The electrochemical behavior of methylene blue (MB) on the ssDNA and dsDNA modified gold electrode were carefully studied. Compared with ssDNA/Au electrode, an increase of redox peak current of MB on dsDNA/Au electrode was found, which could be further used for monitoring the recognition of DNA hybridization. Based on this result, the polymerase chain reaction (PCR) product of the common inserts NOS terminator from real GMOs samples was detected successfully.

18.
J Enzyme Inhib Med Chem ; 22(4): 433-8, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17847709

RESUMO

The whitening effects of the flavonoid constituents of Alpinia officinarum Hance were investigated on melanin biosynthesis in B 16 mouse melanoma cells, tyrosinase inhibition and UV absorption. The melanin content was reduced to 1.276 microg /10(5) cell for flavonoid mixture and 1.161 microg /10(5) cell for galangin while the melanin control was 1.632 microg/10(5) cell. Both flavonoid mixture and galangin reduced melanin production with an inhibition of 21.81% and 28.86% at a concentration of 26.5 microg/mL and 29 microg/mL (107.4 microM), respectively. Tyrosinase inhibition by the flavonoid mixture and galangin were higher at lower concentrations and galangin showed competitive inhibition at a concentration less than 21.23 microg/mL which was soluble. In addition, the flavonoid mixture and galangin showed a broad absorption band at 270 approximately 290 nm related to the UV-B area. These observations suggest that galangin may be a whitening agent and a promising candidate for prevention of skin cancer. This is the first full scale report on the evaluation of the whitening effect of galangin.


Assuntos
Flavonoides/química , Agaricales , Alpinia , Animais , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Flavonoides/farmacologia , Melaninas/química , Melanoma Experimental , Camundongos , Modelos Químicos , Monofenol Mono-Oxigenase/antagonistas & inibidores , Monofenol Mono-Oxigenase/química , Mutagênicos , Sais de Tetrazólio/farmacologia , Tiazóis/farmacologia , Raios Ultravioleta
19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 24(5): 628-30, 2004 May.
Artigo em Chinês | MEDLINE | ID: mdl-15769066

RESUMO

The combination of mid-IR fiber optics and FTIR has made the non-invasive determination of samples in situ, with long distances, and in vivo possible. In this paper domestic mid-IR fiber optics was improved to investigate the transmission ability of fiber optics and its application to the sample determination. New design was applied to obtaining one bare fiber optics, which has a minor energy loss and higher signal-to-noise ratio. The spectra of H2O/EtOH and tissue samples were measured using the new designed fiber optics and the results show that home-made mid-IR fiber optics can be applied to the field of determination of general and biological samples.

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