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1.
Arch Microbiol ; 2020 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-32166358

RESUMO

Enterobacter cloacae is normally considered to be an opportunistic human pathogen. Here, we report on the whole-genome sequence of an endophytic E. cloacae, strain "Ghats1", isolated from leaves of the medicinal plant Coscinium fenestratum Gaertn. Functional analysis of the Ghats1 genome revealed an enrichment for genes involved in the uptake and exchange of nutrients, for chemotaxis and for plant colonization. Unexpectedly though, there were no ORFs belonging to the "virulence factors and antibiotic resistance". Moreover, the presence of hydrolytic enzymes and motility functions reveals the characteristics of an endophyte lifestyle of a bacterium that can colonize and adapt to plant environment. These results provide a better understanding of an endophytic lifestyle through plant-microbe interaction, which can be further exploited as a biocontrol agent.

2.
J Oral Biosci ; 61(4): 207-214, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31669717

RESUMO

OBJECTIVE: To study the effect of radiation therapy on the structural and elemental composition of permanent teeth enamel in vitro. METHODS: Sections from 21 noncarious healthy human teeth were exposed to a cumulative radiation dose of 20-80 Gy. The sections were subjected to electron dispersive spectroscopy (EDS), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analysis to study the elemental composition, the ratio of inorganic and organic content, and the mineralization and crystalline properties of the hydroxyapatite crystal structure respectively. All measures were taken on specified areas of enamel surface before and after radiation exposure and compared. RESULTS: In FTIR and EDS studies, the calcium to phosphorus (Ca/P) and carbonate to phosphate (CO32-/PO3-4) ratios were significantly different (P < 0.05) in teeth sections exposed to 80 Gy, indicating the deterioration of inorganic calcium and phosphorous content. The XRD spectrum data showed loss of peaks at seven specific 2θ coordinate areas, flattened peaks and an increase in the crystallite size in the radiation-exposed groups due to mineralization loss and alteration of the hydroxyapatite crystal matrix in the tooth enamel. CONCLUSIONS: Radiotherapy can induce significant variations in the inorganic and organic functional groups constituting the tooth enamel surface; and these variations are dose dependent. The mechanism responsible for delamination and radiation caries needs to be explored by studying the protein lysis pattern, which might be a leading factor causing the enamel degradation and radiation caries.

3.
In Vitro Cell Dev Biol Anim ; 55(5): 331-340, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30945115

RESUMO

Tetrandrine is a bisbenzylisoquinoline alkaloid known to exhibit anticancer activity against different cancers. In the present study, the cytotoxic effect of tetrandrine isolated from Cyclea peltata on pancreatic (PANC-1) and breast (MDA-MB-231) cancer cells was evaluated in vitro with an attempt to understand the role of tetrandrine on the generation of reactive oxygen species (ROS) and caspase activation. Results demonstrate the dose- and time-dependant cytotoxic effect of tetradrine on both MDA-MB-231 and PANC-1 cells with IC50 values ranging between 51 and 54 µM and 22 and 27 µM for 24 h and 48 h of incubation respectively. In addition, treatment of MDA-MB-231 and PANC-1 cells with tetrandrine showed the shrunken cytoplasm and damaged cell membrane in a dose- and time-dependant manner under the microscope. Also, tetrandrine treatment revealed an elevated levels of reactive oxygen species and increased activities of caspase-8, -9 and -3 confirming the apoptosis of cells through both extrinsic death receptor and intrinsic caspase activation. Therefore, the present study suggests the apoptosis of cells with the activation of caspase pathways mainly intrinsic pathway as a downstream event of tetrandrine-induced ROS generation. Hence, reactive oxygen species-mediated caspase activation pathway may be potentially targeted with the use of tetrandrine to treat breast and pancreatic cancers.


Assuntos
Apoptose/efeitos dos fármacos , Benzilisoquinolinas/farmacologia , Proliferação de Células/efeitos dos fármacos , Cyclea/química , Autofagia/efeitos dos fármacos , Benzilisoquinolinas/química , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Caspases/genética , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
4.
Int J Biol Macromol ; 131: 10-18, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-30851325

RESUMO

Marine bacteria secrete exopolysaccharides (EPS) with unique structural and functional properties and serve as a source of newer bioactive biopolymers. This study reports an EPS produced by a marine bacterium identified as Alteromonas sp. PRIM-28 for its bioactivities. The EPS was characterised using standard methods and tested for its bioactivities using in vitro models. EPS-A28 is an anionic heteropolysaccharide with a molecular weight of 780 kDa and exists as triple helical structure in aqueous solution. Monosaccharide composition is mannuronic acid, glucose and N-acetyl glucosamine repeating units in the ratio 1:3.67:0.93. The FT-IR spectra showed the presence of sulphate, phosphate and uronic acid residues. The thermal analysis showed partial degradation of the EPS-A28 at 190 °C and 40% of residues were stable up to 800 °C. It showed biocompatibility and induced proliferation and migration of dermal fibroblasts (HDF) and keratinocytes. EPS-A28 could increase the S-phase of cell cycle. The proliferative property of the EPS-A28 was established by the increased expression of fibroblast proliferation marker (Ki-67) also its capability of binding to cell surface. It also induced nitric oxide and arginase synthesis in macrophages. These findings suggest that EPS-A28 can be potentially used as a multifunctional bioactive polymer in wound care.


Assuntos
Alteromonas/química , Polissacarídeos Bacterianos/química , Polissacarídeos Bacterianos/farmacologia , Cicatrização/efeitos dos fármacos , Animais , Biomarcadores , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Fibroblastos , Humanos , Queratinócitos , Camundongos , Peso Molecular , Monossacarídeos , Células RAW 264.7 , Termodinâmica
5.
Lett Appl Microbiol ; 68(5): 464-471, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30762887

RESUMO

Increase in infection with multidrug resistant Pseudomonas aeruginosa is a serious global challenge in healthcare. Pseudomonas aeruginosa is capable of causing human infection in various sites and complicates the infection due to its virulence factors. This study was aimed to investigate the effect of quercetin, a dietary flavonoid against the virulence factors of P. aeruginosa and its cell protective effects on epithelial cells. Bactericidal activity, anti-biofilm activity and effect on different virulence factors were carried out using standard methods by using five P. aeruginosa isolates. Cytotoxicity and cell protective effect of quercetin was evaluated by trypan blue dye exclusion assay. All the tested isolates were completely inhibited (100%) by quercetin at a concentration of 500 µg ml-1 . It showed significant (P < 0·05) inhibitory effect on virulence factors including biofilm formation and showed significant protective effect on HEK 293T cells infected with P. aeruginosa strains. This study supports the role of quercetin against P. aeruginosa, by inhibiting virulence factors as well as its cytoprotective activity during bacterial infection either by attenuating the virulence or providing direct protective effect to the host cells. SIGNIFICANCE AND IMPACT OF THE STUDY: The increase in infections caused by opportunistic pathogen Pseudomonas aeruginosa is a serious concern in the health care system. This study describes the beneficial effects of a dietary flavonoid, quercetin against pathogenic P. aeruginosa strains and its protective effect against the P. aeruginosa infection in HEK 293T cells in vitro.


Assuntos
Antibacterianos/farmacologia , Biofilmes/crescimento & desenvolvimento , Pseudomonas aeruginosa/crescimento & desenvolvimento , Quercetina/farmacologia , Biofilmes/efeitos dos fármacos , Linhagem Celular , Farmacorresistência Bacteriana Múltipla , Células HEK293 , Humanos , Testes de Sensibilidade Microbiana , Infecções por Pseudomonas/tratamento farmacológico , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/isolamento & purificação , Virulência , Fatores de Virulência
6.
Obes Surg ; 29(1): 191-196, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30238216

RESUMO

BACKGROUND: The aim of the study was to assess the long-term outcome in terms of weight loss and remission of comorbidities among the patients who had undergone LSG in an Indian setting. METHODS: This is a retrospective observational study of patients (BMI > 30 kg/m2) who underwent LSG having a minimum 6 months of follow-up data. Based on preoperative BMI, patients were grouped as class 1, 30 < BMI < 35 kg/m2; class 2, 35 < BMI < 40 kg/m2; and class 3, BMI > 40 kg/m2. Data on BMI and %EWL between three classes and among genders at different follow-up points for 7 years were compared. RESULT: Study included 95 patients (mean age of 33.7 ± 11 years), and the preoperative mean BMI was 40.2 ± 5.1 kg/m2. At one year of surgery, 85.5% patients achieved > 50%EWL. The highest mean %EWL was found in class 1 (66.19%), followed by class 2 (56.73%) and class 3 (46.59%) at the sixth month follow-up. At the seventh year, %EWLs were 85.11% (class 1), 76.69% (class 2), and 62.98% (class 3) and the mean BMIs were 25.13 ± 3.09 kg/m2 (class 1), 26.86 ± 2.12 kg/m2 (class 2), and 31.07 ± 3.39 kg/m2 (class 3) and were significantly different (p < 0.05). At the last follow-up, though, the males showed slight weight regain; however, there were no statistical differences between the genders (p = 0.065). CONCLUSION: Outcome from LSG was better in patients with BMI < 40 kg/m2 compared to the patients with BMI > 40 kg/m2. Remission of obesity-related comorbidities was observed with LSG in all groups and gender did not influence the outcome significantly.


Assuntos
Gastrectomia , Obesidade/epidemiologia , Obesidade/cirurgia , Adulto , Grupo com Ancestrais do Continente Asiático/estatística & dados numéricos , Índice de Massa Corporal , Comorbidade , Feminino , Seguimentos , Gastrectomia/efeitos adversos , Gastrectomia/estatística & dados numéricos , Humanos , Índia/epidemiologia , Laparoscopia/efeitos adversos , Laparoscopia/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Obesidade/classificação , Obesidade/etnologia , Obesidade Mórbida/classificação , Obesidade Mórbida/epidemiologia , Obesidade Mórbida/cirurgia , Estudos Retrospectivos , Resultado do Tratamento , Perda de Peso , Adulto Jovem
7.
J Appl Microbiol ; 126(2): 641-650, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30372578

RESUMO

AIM: The aim of this study was to investigate the natural variation in the antibiotic sensitivity, biofilm formation and virulence among Pseudomonas aeruginosa isolated from the catheter-associated urinary tract infection (CAUTI) from a single centre. METHODS AND RESULTS: Pseudomonas aeruginosa strains were isolated from the patients with CAUTI after obtaining informed consent. These isolates were identified by routine biochemical methods and 16S rRNA gene sequencing. Antibiotic sensitivity and virulence factors were measured using standard protocols. Crystal violet staining, scanning electron microscopy and confocal laser scanning microscopy were used for the biofilm studies. The extent of infectivity of the strains to induce cell lysis was studied in vitro using the Human Embryonic Kidney cells (HEK 293T). Association between virulence factors, biofilm formation and antibiotic resistance among the strains was analysed statistically. Among the 1266 patients admitted during the 2016-2017 period, 98 cases of CAUTI were reported and 18·36% (n = 18) was due to P. aeruginosa infection. Antibiogram showed that 94·4% of isolates were resistant to multiple antibiotics and 73·7% were carbapenem-resistant. All the isolates formed biofilm on different material surfaces with varying intensity (OD580 ≥0·20-1·11). The biofilm intensity on silicone-latex material was significantly higher compared to the polystyrene surface (P > 0·05). All the strains were highly virulent and able to cause cell killing of HEK 293T cells with a rate ranging from 69·35 to 100% and showed very low sensitivity to healthy human serum. CONCLUSIONS: Antibiotic sensitivity and association between the virulence factors and biofilm formation in the P. aeruginosa clinical strains showed complex natural diversity. SIGNIFICANCE AND IMPACT OF THE STUDY: This study demonstrates the natural diversity and adaptation in virulence factors, biofilm formation and host-pathogen interaction among catheter-associated P. aeruginosa strains. The findings from the study urge for developing individualized drug strategy for targeting these multidrug-resistant pathogens.


Assuntos
Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/patogenicidade , Cateteres Urinários/microbiologia , Infecções Urinárias/microbiologia , Fatores de Virulência/metabolismo , Adaptação Fisiológica , Biodiversidade , Biofilmes/crescimento & desenvolvimento , Farmacorresistência Bacteriana Múltipla , Células HEK293 , Humanos , Pessoa de Meia-Idade , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/isolamento & purificação , Pseudomonas aeruginosa/fisiologia , Silicones
8.
Mol Biol Rep ; 45(6): 2857-2867, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30094529

RESUMO

Wound is a growing healthcare challenge affecting several million worldwide. Lifestyle disorders such as diabetes increases the risk of wound complications. Effective management of wound is often difficult due to the complexity in the healing process. Addition to the conventional wound care practices, the bioactive polymers are gaining increased importance in wound care. Biopolymers are naturally occurring biomolecules synthesized by microbes, plants and animals with highest degree of biocompatibility. The bioactive properties such as antimicrobial, immune-modulatory, cell proliferative and angiogenic of the polymers create a microenvironment favorable for the healing process. The versatile properties of the biopolymers such as cellulose, alginate, hyaluronic acid, collagen, chitosan etc have been exploited in the current wound care market. With the technological advances in material science, regenerative medicine, nanotechnology, and bioengineering; the functional and structural characteristics of biopolymers can be improved to suit the current wound care demands such as tissue repair, restoration of lost tissue integrity and scarless healing. In this review we highlight on the sources, mechanism of action and bioengineering approaches adapted for commercial exploitation.


Assuntos
Biopolímeros/uso terapêutico , Engenharia Tecidual/métodos , Cicatrização/efeitos dos fármacos , Alginatos/uso terapêutico , Animais , Celulose/uso terapêutico , Quitosana/uso terapêutico , Colágeno/uso terapêutico , Humanos , Ácido Hialurônico/uso terapêutico , Medicina Regenerativa/métodos , Pele/metabolismo , Transplante de Pele/métodos
9.
Int J Biol Macromol ; 116: 45-53, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29733927

RESUMO

The current study delineates the preparation of novel chitosan grafted silk fibre reinforced Poly (vinyl alcohol) (PVA) composite films with desirable properties. Although silk fibroin has been extensively used for various biomedical applications, its properties could be further re-tailored for its suitability in the field of regenerative medicine. Chitosan was successfully grafted over silk, via acylation with succinic anhydride and thereby the fibres were incised and used for the preparation of the films. The grafted silk fibre reinforced PVA films were subjected to FTIR studies, microscopic analysis by atomic force microscopy (AFM) and optical microscopy techniques, X-ray diffraction (XRD) analysis and further evaluated for in vitro biocompatibility studies. The composite films demonstrated improved surface roughness with increasing concentration of the fibre and its dispersion in the polymer matrix was observed. Furthermore, in vitro biocompatibility and cellular behaviour such as adhesion and proliferation of mouse fibroblasts as well as astrocyte cells was studied and the results showed improved proliferative activity, when compared to the pristine PVA films. These results were further supported by the results confirmed by MTT assay demonstrating the films to be non-toxic. The efficiency and feasibility of the films to be used for tissue engineering, was further evaluated by haemocompatibility studies using human erythrocytes, thus making them a potential material to be used for biomedical applications.


Assuntos
Materiais Biocompatíveis/química , Quitosana/química , Fibroínas/química , Álcool de Polivinil/química , Seda/química , Animais , Astrócitos/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Fibroínas/farmacologia , Humanos , Camundongos , Células NIH 3T3 , Polímeros/química , Seda/farmacologia , Propriedades de Superfície , Engenharia Tecidual/métodos
10.
Obes Surg ; 28(9): 2811-2814, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29679335

RESUMO

BACKGROUND: Recent Research evidences from across the world indicate the usefulness of bariatric surgery in improving the immunological co-morbidities in patients with morbid obesity. AIM: The aim of the study was to evaluate the outcome from bariatric surgery in patients presenting with diabetes mellitus and or morbid obesity with immunological co-morbidities. METHODS: It was a retrospective cross-sectional study. Study included patients with morbid obesity with immunological co-morbidities, and additional co- morbidity of type 2 diabetes mellitus in about one third of the cases, who had undergone bariatric surgery during the period 2014-2016 at our center. Patient demographics, preoperative data, and follow-up data were collected and analyzed. Patients were followed for assessing the outcome in terms of BMI and dependency on medications to evaluate the effectiveness of the procedure. RESULTS: The study included 23 patients (52% female and 48% male). Bariatric surgery was effective in all the patients (except one) in weight reduction. Significant reduction in weight and BMI was observed (p < 0.05). The recent follow-up of these patients showed that the mean BMI of the study group decreased significantly, 34.4% patients had attained normal BMI ≤ 25 kg/m2. Three-month follow-up indicated that 55.56% were not dependent on medications. At 1-year follow-up, 94.4% patients were without any dependency on immunosuppressive medications. Complications included a reversal of surgery and a case of mortality. CONCLUSION: The results of our study have shown that immune-compromised patients can undergo bariatric surgery with good weight loss results and improvement in co-morbidities.


Assuntos
Cirurgia Bariátrica , Hospedeiro Imunocomprometido , Obesidade Mórbida , Cirurgia Bariátrica/efeitos adversos , Cirurgia Bariátrica/estatística & dados numéricos , Comorbidade , Estudos Transversais , Feminino , Humanos , Masculino , Obesidade Mórbida/epidemiologia , Obesidade Mórbida/cirurgia , Estudos Retrospectivos , Resultado do Tratamento
11.
Int J Syst Evol Microbiol ; 68(4): 1037-1046, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29458496

RESUMO

A Gram-stain-negative, aerobic, non-endospore-forming organism, isolated from the rhizosphere sand of a coastal sand dune plant was studied for its taxonomic position. On the basis of 16S rRNA gene sequence similarity comparisons, strain YU-PRIM-29T was grouped within the genus Halomonas and was most closely related to Halomonas johnsoniae (97.5 %). The 16S rRNA gene sequence similarity to other Halomonas species was <97.5 %. Strain YU-PRIM-29T grew optimally at 28 °C (growth range, 10-36 °C), at a pH of 7-9 (growth range, pH 5.5-12.0) and in the presence of 0.5 to 5 % (w/v) NaCl (growth up to 20 % NaCl). The fatty acid profile from whole-cell hydrolysates supported the allocation of the strain to the genus Halomonas. The fatty acids C18 : 1ω7c and C16 : 0 were found as major compounds, followed by the hydroxylated fatty acid C12 : 0 3-OH. The quinone system consisted predominantly of ubiquinone Q-9. The polar lipid profile was composed of the major lipids diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. In the polyamine pattern, spermidine was the predominant compound. The DNA G+C content was 64.8 mol%. In addition, the results of physiological and biochemical tests also allowed phenotypic differentiation of strain YU-PRIM-29T from its closest-related species. Hence, YU-PRIM-29T represents a new species of the genus Halomonas, for which we propose the name Halomonas malpeensis sp. nov., with YU-PRIM-29T (=LMG 28855T=CCM 8737T) as the type strain.


Assuntos
Halomonas/classificação , Filogenia , Rizosfera , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Halomonas/genética , Halomonas/isolamento & purificação , Índia , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/química
12.
Lett Appl Microbiol ; 64(3): 231-238, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28035685

RESUMO

Quorum sensing (QS) has been shown to play a crucial role in the pathogenesis in many bacteria, and attenuation of QS is one of the targets of antimicrobial therapy with particular interest in combating drug resistance. This study reports the QS inhibitory activity of metabolites from Cassia alata L. (Ca. alata), an important medicinal herb widely used in the treatment of microbial infections. For investigating the QS inhibition (QSI), the potential of Ca. alata L., initially, metabolites of the leaves extracted using ethanol was tested against biosensor strain Chromobacterium violaceum CV026 and C. violaceum wild-type strains. Furthermore, a purified fraction rich in flavonoids (F-AF) was used for establishing QSI activity by studying the inhibition of violacein production in C. violaceum, and QS controlled virulence and biofilm formation in Pseudomonas aeruginosa PAO1. The study results showed 50% inhibition of violacein production in C. violaceum at 0·05 mg ml-1 concentration of F-AF. In P. aeruginosa PAO1, it inhibited the tested virulence factors and biofilm formation significantly. The F-AF contained major flavonoids namely, quercetin, quercetrin and kaempferol displaying QSI activity individually against the test organisms. SIGNIFICANCE AND IMPACT OF THE STUDY: Present study demonstrates the quorum sensing inhibitory activity of metabolites from Cassia alata, an important medicinal herb which is commonly used worldwide in the treatment of infections caused by microorganisms. An extract prepared from the leaves of the plant showed activity against quorum sensing in Chromobacterium violaceum and was also effective against attenuating the quorum sensing controlled virulence factors in Pseudomonas aeruginosa. Activity is attributed to the rich flavonoid composition of the plant. Results of the present investigation throw an insight into the possibility of developing drug formulations using the isolated compounds against infections caused by quorum sensing-mediated pathogenicity of bacteria.


Assuntos
Antibacterianos/farmacologia , Cassia/química , Chromobacterium/efeitos dos fármacos , Extratos Vegetais/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Percepção de Quorum/efeitos dos fármacos , Antibacterianos/isolamento & purificação , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Chromobacterium/genética , Chromobacterium/fisiologia , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Plantas Medicinais/química , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/fisiologia , Fatores de Virulência/genética , Fatores de Virulência/metabolismo
13.
Ren Fail ; 38(5): 770-5, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26984368

RESUMO

Uranium is a radioactive heavy metal ubiquitous in the natural environment. In its chemical form, it is known to induce nephrotoxicity both in human and in animals. Its toxicity is dose and time dependent, also varies with form of uranium. In the present study, we assessed the nephrotoxicity induced by a single dose of uranyl nitrate (UN) in mice at different time intervals and recovery from its toxicity. Two doses of 2 and 4 mg/kg body weight of uranyl nitrate was injected intraperitoneally and animals were sacrificed after 1, 3, 5, 14, and 28 d of administration. Histopathological and biochemical alterations of post-UN dosing in comparison to control were evaluated. Tubular damage to about 75% was observed after 3 d (4 mg/kg) and the biochemical parameters such as serum creatinine, urea, and blood urea nitrogen levels were also significantly increased. Progression of tubular damage was not found after 5 d. Dose-dependent recovery of uranyl nitrate-treated animals was observed after 14 and 28 d of dosing. The concentration of uranium retained in kidney correlates with biochemical and histopathological analysis.


Assuntos
Túbulos Renais , Nitrato de Uranil/toxicidade , Lesão Renal Aguda/diagnóstico , Lesão Renal Aguda/etiologia , Lesão Renal Aguda/patologia , Animais , Creatinina/sangue , Modelos Animais de Doenças , Progressão da Doença , Relação Dose-Resposta à Radiação , Testes de Função Renal/métodos , Túbulos Renais/patologia , Túbulos Renais/efeitos da radiação , Camundongos , Recuperação de Função Fisiológica , Fatores de Tempo , Ureia/sangue
14.
Int J Biol Macromol ; 85: 400-4, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26772917

RESUMO

Exopolysaccharides (EPS) produced by bacteria are important source of natural biomolecules with therapeutic applications. In this study EPS produced by a strain PRIM-31 isolated from seawater from south west coast of India identified by 16S rRNA gene sequencing as Nitratireductor sp. was investigated for its biotechnological applications. The isolate produced 650 mg L(-1) EPS under optimum growth conditions. The purified EPS contained 58.3% carbohydrates with 7.08% uronic acid containing sugars, functional groups such as sulfate (2.68%) and trace amounts of proteins (0.65%). Molecular weight of the EPS was 90 kDa and monosaccharide composition was arabinose, glucose, xylose, glucuronic acid and galactose (6.6: 3.5: 2.1: 1.3: 1). The EPS displayed antioxidant activity in terms of total antioxidant capacity, ferric reducing power, scavenging of DPPH (IC50 390 µg mL(-1)) and superoxide radicals (IC50 340 µg mL(-1)). Cell proliferative activity of the EPS was evidenced by significant improvement in human dermal fibroblast (HDF) proliferation compared to control. Further, significant improvement (41%) in HDF cell migration was observed in in vitro scratch assay with EPS treatment. The EPS also showed antiproliferative activity against glioblastoma cells with an IC50 of 234.04 µg mL(-1). These functional properties of the EPS prospect its biotechnological applications.


Assuntos
Alphaproteobacteria/metabolismo , Polissacarídeos Bacterianos/química , Polissacarídeos Bacterianos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Humanos , Polissacarídeos Bacterianos/toxicidade , Espectroscopia de Infravermelho com Transformada de Fourier
15.
J Microbiol Immunol Infect ; 49(1): 8-15, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24856426

RESUMO

BACKGROUND/PURPOSE: Inhibition of quorum sensing (QS), a cell-density dependent regulation of gene expression in bacteria by autoinducers is an attractive strategy for the development of antipathogenic agents. METHODS: In this study, the anti-QS activity of the ethanolic extract of the traditional herb Centella asiatica was investigated by the biosensor bioassay using Chromobacterium violaceum CV026. The effect of ethyl acetate fraction (CEA) from the bioassay-guided fractionation of ethanol extract on QS-regulated violacein production in C. violaceum ATCC12472 and pyocyanin production, proteolytic and elastolytic activities, swarming motility, and biofilm formation in Pseudomonas aeruginosa PAO1 were evaluated. Possible mechanism of QS-inhibitory action on autoinducer activity was determined by measuring the acyl homoserine lactone using C. violaceum ATCC31532. Anti-QS compounds in the CEA fraction were identified using thin layer chromatography biosensor overlay assay. RESULTS: Ethanol extract of C. asiatica showed QS inhibition in C. violaceum CV026. Bioassay-guided fractionation of ethanol extract revealed that CEA was four times more active than the ethanol extract. CEA, at 400 µg/mL, completely inhibited violacein production in C. violaceum ATCC12472 without significantly affecting growth. CEA also showed inhibition of QS-regulated phenotypes, namely, pyocyanin production, elastolytic and proteolytic activities, swarming motility, and biofilm formation in P. aeruginosa PAO1 in a concentration-dependent manner. Thin layer chromatography of CEA with biosensor overlay showed anti-QS spot with an Rf value that corresponded with that of standard kaempferol. CONCLUSION: The anti-QS nature of C. asiatica herb can be further exploited for the formulation of drugs targeting bacterial infections where pathogenicity is mediated through QS.


Assuntos
Antibacterianos/farmacologia , Centella/química , Flavonoides/farmacologia , Extratos Vegetais/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/fisiologia , Percepção de Quorum/efeitos dos fármacos , Antibacterianos/isolamento & purificação , Técnicas Biossensoriais/métodos , Chromobacterium/efeitos dos fármacos , Flavonoides/isolamento & purificação , Extratos Vegetais/isolamento & purificação
16.
Carbohydr Polym ; 126: 215-21, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-25933542

RESUMO

Exopolysaccharides (EPS) produced by bacteria have attracted scientific and industrial attention due to their multifunctional properties and relatively easier production. In this study, an EPS viz., R-PS18 produced by Rhizobium sp. PRIM-18 was characterized and its functional properties were assessed. Cell proliferative and in vitro wound healing activities of the EPS were established using human dermal fibroblast (HDF) cells. The isolate produced 2.1 g L(-1) purified EPS (molecular weight 9.33×10(6) Da) comprising of glucose, galactose, and mannose (6.1:1.8:1). Viscosity of 0.25% solution was 23.4 mPa s (shear rate 75 s(-1)) and it showed pseudoplastic and thixotropic behavior. High emulsification, iron chelation, and superoxide scavenging abilities were also observed. Significant increase in HDF cell proliferation and wound healing in vitro was achieved by R-PS18 treatment. Sulfation of R-PS18 significantly enhanced the cell proliferative and wound healing activities. In conclusion, these findings indicate potential applications of R-PS18.


Assuntos
Polissacarídeos Bacterianos/química , Polissacarídeos Bacterianos/farmacologia , Rhizobium/química , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Emulsificantes/química , Emulsificantes/isolamento & purificação , Emulsificantes/farmacologia , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Humanos , Polissacarídeos Bacterianos/isolamento & purificação , Viscosidade , Cicatrização/efeitos dos fármacos
17.
Hum Exp Toxicol ; 34(5): 548-56, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25233896

RESUMO

As a bone mineral component, hydroxyapatite (HA) has been an attractive bioceramic for the reconstruction of hard tissues. However, its poor mechanical properties, including low fracture toughness and tensile strength, have been a substantial challenge to the application of HA for the replacement of load-bearing and/or large bone defects. In this study, HA is reinforced with high-purity and well-functionalized multiwalled carbon nanotubes (MWCNTs; >99 wt%) having an average diameter of 15 nm and length from 10 to 20 µm. The cellular response of these functionalized CNTs and its composites were examined in human osteoblast sarcoma cell lines. Calcium nitrate tetrahydrate (Ca(NO3)2·4H2O) and diammonium hydrogen phosphate ((NH4)2HPO4) were used to synthesize HA in situ. MWCNTs were functionalized by heating at 100°C in 3:1 ratio of sulfuric acid and nitric acid for 60 min with stirring and dispersed in sodium dodecyl benzene sulfonate by sonication. HA particles were produced in MWCNTs solution by adding Ca(NO3)2·4H2O and (NH4)2HPO4 under vigorously stirring conditions. The composite was dried and washed in distilled water followed by heat treatment at 250°C to obtain CNT-HA powder. Physiochemical characterization of the composite material was carried out using Fourier transform infrared spectroscopy, field-emission scanning electron microscopy, energy-dispersive X-ray spectrometer, and X-ray diffractometer. Furthermore, this study investigates the cytotoxic effects of functionalized-MWCNTs (f-MWCNTs) and its composites with HA in human osteoblast sarcoma cell lines. Human osteoblast cells were exposed with different concentrations of f-MWCNTs and its composite with HA. The interactions of f-MWCNT and MWCNT-HA composites were analyzed by 3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay. The results indicate no detrimental effect on survival or mitochondrial activity of the osteoblast cells. Cell viability decreased with an increase in CNT concentration indicating that MWCNTs and its composite can be cytotoxic at higher dosages. This result provides further evidence that the bionano interface can be developed for CNT-reinforced HA composites for load-bearing bone implants, drug delivery, and tissue engineering.


Assuntos
Materiais Biocompatíveis/toxicidade , Durapatita/toxicidade , Nanotubos de Carbono/química , Osteoblastos/efeitos dos fármacos , Materiais Biocompatíveis/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Durapatita/química , Humanos , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Difração de Raios X
18.
Pol J Microbiol ; 63(1): 115-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25033672

RESUMO

Zeaxanthin, a C40xanthophyll carotenoid, has potential biological applications in nutrition and human health. In this study we characterized carotenoid composition in 5 taxonomically related marine bacterial isolates from the genus Muricauda. The pigment was characterized using high performance liquid chromatography (HPLC) and mass spectrometry, which confirmed the presence of all-trans-zeaxanthin. Muricauda strains produced zeaxanthin as a predominant carotenoid. M. flavescens JCM 11812(T) produced highest yield (4.4 +/- 0.2 mg L(-1)) when cultured on marine broth at 32 degrees C for 72 h. This is the first report on the presence of zeaxanthin among the majority of species from the genus Muricauda.


Assuntos
Flavobacteriaceae/metabolismo , Xantofilas/biossíntese , Flavobacteriaceae/classificação , Filogenia , Especificidade da Espécie , Zeaxantinas
19.
Appl Biochem Biotechnol ; 171(4): 817-31, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23900617

RESUMO

Zeaxanthin carotenoids are class of commercially important natural products and diverse biomolecules produced by plants and many microorganisms. Bacteria often produce a cocktail of polar and nonpolar carotenoids limiting their industrial applications. Marine members of the family Flavobacteriaceae are known to produce potential carotenoids such as astaxanthin and zeaxanthin. A few bacterial species have been reported for the predominant production zeaxanthin. Here, we report the molecular identification of the zeaxanthin as a major carotenoid produced by two novel bacteria (YUAB-SO-11 and YUAB-SO-45) isolated from sandy beaches of South West Coast of India and the effect of carbon sources on the production of zeaxanthin. The strains were identified based on the 16S rRNA gene sequencing as a member of genus Muricauda. The closest relatives of YUAB-SO-11 and YUAB-SO-45 were Muricauda aquimarina (JCM 11811(T)) (98.9 %) and Muricauda olearia (JCM 15563(T)) (99.2 %), respectively, indicating that both of these strains might represent a novel species. The highest level of zeaxanthin production was achieved (YUAB-SO-11, 1.20 ± 0.11 mg g(-1)) and (YUAB-SO-45, 1.02 ± 0.13 mg g(-1)) when cultivated in marine broth supplemented with 2 % NaCl (pH 7) and incubated at 30 °C. Addition of 0.1 M glutamic acid, an intermediate of citric acid cycle, enhanced the zeaxanthin production as 18 and 14 % by the strains YUAB-SO-11 and YUAB-SO-45 respectively. The zeaxanthin showed in vitro nitric oxide scavenging, inhibition of lipid peroxidation, and 2,2-diphenyl-1-picryl hydrazyl scavenging activities higher than the commercial zeaxanthin. The results of this study suggest that two novel strains YUAB-SO-11 and YUAB-SO-45 belonging to genus Muricauda produce zeaxanthin as a predominant carotenoid, and higher production of zeaxanthin was achieved on glutamic acid supplementation. The pigment showed good in vitro antioxidant activity, which can be exploited further for commercial applications.


Assuntos
Flavobacteriaceae/metabolismo , Xantofilas/metabolismo , Antioxidantes/metabolismo , Flavobacteriaceae/classificação , Flavobacteriaceae/genética , Índia , RNA Ribossômico 16S/genética , Água do Mar/microbiologia , Dióxido de Silício , Zeaxantinas
20.
Int J Syst Evol Microbiol ; 63(Pt 11): 4100-7, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23749276

RESUMO

An aerobic, Gram-negative, rod-shaped bacterium with polar flagella, strain CC-AFH3(T), was isolated from an oil-contaminated site located in Kaohsiung county, Taiwan. Strain CC-AFH3(T) grew at 20-40 °C, pH 5.0-10.0 and <2 % (w/v) NaCl. 16S rRNA gene sequence analysis indicated that strain CC-AFH3(T) showed the greatest degree of similarity to Herbaspirillum soli SUEMI10(T) (96.5 %), H. aurantiacum SUEMI08(T) (96.3 %), H. canariense SUEMI03(T) (96.0 %), H. psychrotolerans PB1(T) (95.4 %) and members of other Herbaspirillum species (94.1-95.2 %), and lower similarity to members of other genera (<94 %). Phylogenetic analyses also positioned the novel strain in the genus Herbaspirillum as an independent lineage. The major fatty acids in strain CC-AFH3(T) were C10 : 0 3-OH, C12 : 0, C14 : 0 2-OH, C16 : 0, iso-C15 : 0 3-OH, C17 : 0 cyclo, C16 : 1ω7c/C16 : 1ω6c and C18 : 1ω7c/C18 : 1ω6c. The major polar lipids of strain CC-AFH3(T) were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and phosphatidylcholine. The predominant quinone was ubiquinone 8 (Q-8) and the DNA G+C content was 63.4 mol%. On the basis of 16S rRNA gene sequence analysis in combination with physiological and chemotaxonomic data, strain CC-AFH3(T) represents a novel species in a new genus, for which we propose the name Noviherbaspirillum malthae gen. nov., sp. nov.; the type strain of Noviherbaspirillum malthae is CC-AFH3(T) ( = BCRC 80516(T) = JCM 18414(T)). We also propose the reclassification of Herbaspirillum soli, Herbaspirillum aurantiacum, Herbaspirillum canariense and 'Herbaspirillum psychrotolerans' as Noviherbaspirillum soli comb. nov. (type strain SUEMI10(T) = LMG 26149(T) = CECT 7840(T)), Noviherbaspirillum aurantiacum comb. nov. (type strain SUEMI08(T) = LMG 26150(T) = CECT 7839(T)), Noviherbaspirillum canariense comb. nov. (type strain SUEMI03(T) = LMG 26151(T) = CECT 7838(T)) and Noviherbaspirillum psychrotolerans comb. nov. (type strain PB1(T) = DSM 26001(T) = LMG 27282(T)), respectively. An emended description of Herbaspirillum seropedicae is also presented.


Assuntos
Herbaspirillum/classificação , Filogenia , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Herbaspirillum/genética , Herbaspirillum/isolamento & purificação , Dados de Sequência Molecular , Poluição por Petróleo , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Poluentes do Solo , Taiwan , Ubiquinona/química
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