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1.
Sci Rep ; 12(1): 19250, 2022 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-36357447

RESUMO

Recent breakthroughs in the field of nanoparticle-based therapeutic delivery methods have changed the standpoint of cancer therapy by effectively delaying the process of disease development. Nanoparticles have a unique capacity of good penetrating ability than other therapeutic leads used in traditional therapeutics, and also, they have the highest impact on disease management. In the current study isolongifolene-loaded Chitosan nanoparticles have been formulated, synthesized and then characterized by the use of Fourier Transform Infrared Spectroscopy, X-ray Diffraction, Scanning Electron Microscopy and Transmission Electron Microscopy. Further, the characterized chitosan nano formulation was evaluated for hemocompatibility, plasma stability, and in-vitro release. Isolongifolene-loaded chitosan nanoparticles were found to be compatible with plasma and also, they exhibited a constant release pattern. Hence, chitosan-loaded nanoparticles could be employed as an excellent adjuvant in cancer therapeutic, to combat the multi-drug resistance in solid tumors.


Assuntos
Quitosana , Nanopartículas , Neoplasias , Quitosana/química , Nanopartículas/química , Microscopia Eletrônica de Transmissão , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X , Tamanho da Partícula , Portadores de Fármacos/química , Neoplasias/tratamento farmacológico
2.
Int J Biol Macromol ; 194: 870-881, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34843816

RESUMO

Marine ecosystem associated organisms are an affluent source of bioactive compounds. Polysaccharides with unique structural and practical entities have gained special studies interest inside the current biomedical zone. Polysaccharides are the main components of marine algae, plants, animals, insects, and microorganisms. In recent times research on seaweed is more persistent for extraction of natural bioactive "Sulfated polysaccharides" (SPs). The considerable amount of SP exists in the algae in the form of fucans, fucoidans, carrageenans, ulvan, etc. Major function of SPs is to act as a defensive lattice towards the infective organism. All SPs possess the high potential and possess a broad range of therapeutic applications as antitumor, immunomodulatory, vaccine adjuvant, anti-inflammatory, anticoagulant, antiviral, antiprotozoal, antimicrobial, antilipemic, therapy of regenerative medicine, also in drug delivery and tissue engineering application. This review aims to discuss the biomedicine applications of sulfated polysaccharides from marine seaweeds.


Assuntos
Organismos Aquáticos/química , Pesquisa Biomédica , Polissacarídeos/química , Sulfatos/química , Materiais Biocompatíveis/química , Fenômenos Químicos , Carboidratos da Dieta , Sistemas de Liberação de Medicamentos , Desenvolvimento de Medicamentos , Estrutura Molecular , Plantas/química , Polissacarídeos/farmacologia , Alga Marinha/química , Engenharia Tecidual
3.
J Photochem Photobiol B ; 203: 111773, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31931385

RESUMO

Glioma is the prime cause of cancer allied mortality in adolescent people and it accounts about 80% of all malignant tumours. Eugenol is a major bioactive constituent present in the essential oils with numerous pharmacological benefits including nueroprotective activity. The major drawback of eugenol is its extreme volatile property and oxygen sensitivity therefore we increased the efficacy of drug; eugenol by encapsulating with chitosan polymer. Eugenol loaded chitosan polymer (EuCs) was characterized using FTIR, XRD, SEM, HR-TEM analysis and the encapsulation, drug release efficacy was assessed at in vitro condition. The induction of autophagy and anticancer efficacy of EuCs on glioma cells was evaluated with rat C6 glioma cells using MTT assay, acridine orange staining, immunocytochemical analysis of NFκß protein expression and FLOW cytometric analysis. The anti-metastatic property of Eu-CS was assessed by immunoblotting and RT-PCR analysis of epithelial mesenchymal transition protein expression in EuCs treated rat C6 glioma cells. Our characterization analysis proves that EuCs possess essential physical and functional properties of copolymer to be utilized as a drug. Further the MTT analysis and AO staining confirms even in the presence of oncogenic inducer and autophagic inhibitors, EuCs exhibits apoptotic potency on rat C6 glioma cells. The result of immunocytochemical studies depicts the inhibition of NFκß protein expression and flow cytometry studies confirm apoptosis induction by EuCs. The inhibition of metastasis by EuCs was proven by the decrease in epithelial mesenchymal transition protein expression in Eu-Cs treated rat C6 glioma cells. Over all our results authentically confirms eugenol loaded chitosan nanopolymer persuasively induces apoptosis and inhibits metastasis in rat C6 glioma cells.


Assuntos
Antineoplásicos/química , Apoptose/efeitos dos fármacos , Quitosana/química , Eugenol/química , Metaloproteinase 9 da Matriz/metabolismo , Nanoestruturas/química , Transdução de Sinais/efeitos dos fármacos , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Portadores de Fármacos/química , Eugenol/farmacologia , Glioma/metabolismo , Glioma/patologia , NF-kappa B/metabolismo , Ratos , Ativador de Plasminogênio Tipo Uroquinase/metabolismo
4.
J Clin Neurosci ; 31: 219-23, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27396378

RESUMO

The use of cobalt chrome (CoCr) implants in spinal surgery has become increasingly popular. However, there have been no studies specifically comparing biofilm formation on CoCr with that of titanium-alloy spinal implants. The objective of this study was to compare the difference in propensity for biofilm formation between these two materials, as it specifically relates to spinal rods. Staphylococcus aureus subsp. Aureus (ATCC 6538) were incubated with two different types of spinal rods composed of either CoCr or titanium-alloy. The spinal rods were then subject to a trypsin wash to allow for isolation of the colonized organism and associated biofilms. The associated optical density values (OD) from the bacterial isolates were obtained and the bacterial solutions were plated on brain-heart infusion agar plates and the resultant colony-forming units (CFU) were counted. The OD values for the titanium-alloy rods were 1.105±0.096nm (mean±SD) and 1.040±0.026nm at 48hours and 96hours, respectively. In contrast, the OD values for the CoCr rods were 1.332±0.161nm and 1.115±0.207nm at 48 and 96hours, respectively (p<0.05). The CFU values were 1481±417/100mm(2) and 745±159/100mm(2) at 48 and 96hours, respectively for the titanium-alloy group. These values were significantly lower than the CFU values obtained from the CoCr group which were 2721±605/100mm(2) and 928±88/100mm(2) (p<0.001) at both 48 and 96hours respectively. Our findings, evaluating both the OD and CFU values, indicate that implants composed of CoCr had a higher proclivity towards biofilm formation compared to titanium-alloy implants.


Assuntos
Biofilmes/crescimento & desenvolvimento , Ligas de Cromo , Próteses e Implantes/microbiologia , Infecções Relacionadas à Prótese/microbiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/fisiologia , Titânio , Humanos , Procedimentos Ortopédicos/instrumentação , Coluna Vertebral/cirurgia
5.
J Bacteriol ; 196(23): 4057-70, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25225267

RESUMO

The adaptation of Porphyromonas gingivalis to H2O2-induced stress while inducible is modulated by an unknown OxyR-independent mechanism. Previously, we reported that the PG_2212 gene was highly upregulated in P. gingivalis under conditions of prolonged oxidative stress. Because this gene may have regulatory properties, its function in response to H2O2 was further characterized. PG2212, annotated as a hypothetical protein of unknown function, is a 10.3-kDa protein with a cysteine 2-histidine 2 (Cys2His2) zinc finger domain. The isogenic mutant P. gingivalis FLL366 (ΔPG_2212) showed increased sensitivity to H2O2 and decreased gingipain activity compared to the parent strain. Transcriptome analysis of P. gingivalis FLL366 revealed that approximately 11% of the genome displayed altered expression (130 downregulated genes and 120 upregulated genes) in response to prolonged H2O2-induced stress. The majority of the modulated genes were hypothetical or of unknown function, although some are known to participate in oxidative stress resistance. The promoter region of several of the most highly modulated genes contained conserved motifs. In electrophoretic mobility shift assays, the purified rPG2212 protein did not bind its own promoter region but bound a similar region in several of the genes modulated in the PG_2212-deficient mutant. A metabolome analysis revealed that PG2212 can regulate a number of genes coding for proteins involved in metabolic pathways critical for its survival under the conditions of oxidative stress. Collectively, our data suggest that PG2212 is a transcriptional regulator that plays an important role in oxidative stress resistance and virulence regulation in P. gingivalis.


Assuntos
Regulação Bacteriana da Expressão Gênica , Peróxido de Hidrogênio/toxicidade , Estresse Oxidativo , Porphyromonas gingivalis/efeitos dos fármacos , Porphyromonas gingivalis/fisiologia , Estresse Fisiológico , Fatores de Transcrição/metabolismo , DNA Bacteriano/metabolismo , Ensaio de Desvio de Mobilidade Eletroforética , Deleção de Genes , Perfilação da Expressão Gênica , Porphyromonas gingivalis/genética , Ligação Proteica , Fatores de Transcrição/genética , Dedos de Zinco
6.
PLoS One ; 8(8): e69645, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23990885

RESUMO

As an anaerobe, Porphyromonas gingivalis is significantly affected by the harsh inflammatory environment of the periodontal pocket during initial colonization and active periodontal disease. We reported previously that the repair of oxidative stress-induced DNA damage involving 8-oxo-7,8-dihydroguanine (8-oxoG) may occur by an undescribed mechanism in P. gingivalis. DNA affinity fractionation identified PG1037, a conserved hypothetical protein, among other proteins, that were bound to the 8-oxoG lesion. PG1037 is part of the uvrA-PG1037-pcrA operon in P. gingivalis which is known to be upregulated under H2O2 induced stress. A PCR-based linear transformation method was used to inactivate the uvrA and pcrA genes by allelic exchange mutagenesis. Several attempts to inactivate PG1037 were unsuccessful. Similar to the wild-type when plated on Brucella blood agar, the uvrA and pcrA-defective mutants were black-pigmented and beta-hemolytic. These isogenic mutants also had reduced gingipain activities and were more sensitive to H2O2 and UV irradiation compared to the parent strain. Additionally, glycosylase assays revealed that 8-oxoG repair activities were similar in both wild-type and mutant P. gingivalis strains. Several proteins, some of which are known to have oxidoreducatse activity, were shown to interact with PG1037. The purified recombinant PG1037 protein could protect DNA from H2O2-induced damage. Collectively, these findings suggest that the uvrA-PG1037-pcrA operon may play an important role in hydrogen peroxide stress-induced resistance in P. gingivalis.


Assuntos
Proteínas de Bactérias/genética , Genes Bacterianos/genética , Óperon , Estresse Oxidativo , Porphyromonas gingivalis/metabolismo , Adesinas Bacterianas/metabolismo , Alelos , Proteínas de Bactérias/fisiologia , Cisteína Endopeptidases/metabolismo , DNA Glicosilases/metabolismo , DNA Bacteriano/química , DNA Bacteriano/genética , Genes Bacterianos/fisiologia , Teste de Complementação Genética , Vetores Genéticos , Cisteína Endopeptidases Gingipaínas , Guanosina/análogos & derivados , Guanosina/química , Peróxido de Hidrogênio/química , Inflamação , Espectrometria de Massas , Mutagênese , Mutação , Reação em Cadeia da Polimerase , Porphyromonas gingivalis/genética , Mapeamento de Interação de Proteínas , Estrutura Terciária de Proteína , Proteínas Recombinantes/metabolismo
7.
PLoS One ; 8(5): e63367, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23717416

RESUMO

Previously, we have reported that gingipain activity in Porphyromonas gingivalis, the major causative agent in adult periodontitis, is post-translationally regulated by the unique Vim proteins including VimF, a putative glycosyltransferase. To further characterize VimF, an isogenic mutant defective in this gene in a different P. gingivalis genetic background was evaluated. In addition, the recombinant VimF protein was used to further confirm its glycosyltransferase function. The vimF-defective mutant (FLL476) in the P. gingivalis ATCC 33277 genetic background showed a phenotype similar to that of the vimF-defective mutant (FLL95) in the P. gingivalis W83 genetic background. While hemagglutination was not detected and autoaggregation was reduced, biofilm formation was increased in FLL476. HeLa cells incubated with P. gingivalis FLL95 and FLL476 showed a 45% decrease in their invasive capacity. Antibodies raised against the recombinant VimF protein in E. coli immunoreacted only with the deglycosylated native VimF protein from P. gingivalis. In vitro glycosyltransferase activity for rVimF was observed using UDP-galactose and N-acetylglucosamine as donor and acceptor substrates, respectively. In the presence of rVimF and UDP-galactose, a 60 kDa protein from the extracellular fraction of FLL95 which was identified by mass spectrometry as Rgp gingipain, immunoreacted with the glycan specific mAb 1B5 antibody. Taken together, these results suggest the VimF glycoprotein is a galactosyltransferase that may be specific for gingipain glycosylation. Moreover, galatose is vital for the growing glycan chain.


Assuntos
Adesinas Bacterianas/metabolismo , Cisteína Endopeptidases/metabolismo , Precursores Enzimáticos/metabolismo , Galactose/metabolismo , Galactosiltransferases/metabolismo , Porphyromonas gingivalis/enzimologia , Biofilmes , Clonagem Molecular , Galactosiltransferases/química , Galactosiltransferases/genética , Técnicas de Inativação de Genes , Cisteína Endopeptidases Gingipaínas , Glicosilação , Cinética , Fenótipo , Porphyromonas gingivalis/genética , Porphyromonas gingivalis/crescimento & desenvolvimento , Porphyromonas gingivalis/ultraestrutura , Processamento de Proteína Pós-Traducional
8.
Int Forum Allergy Rhinol ; 3(2): 94-8, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23192968

RESUMO

BACKGROUND: Antibiotic irrigations are occasionally used during endoscopic sinus surgery when gross mucosal infection is present. These irrigations are thought to flush out pathogenic bacteria and decrease the bacterial load within the mucosal surfaces. This treatment, however, has not been studied in vivo and it is unknown whether antibiotic rinses produce a quantitative reduction in pathologic bacteria within the sinus mucosa. The objective of this study was to determine the relative abundance of Staphylococcus aureus within the maxillary sinus and to evaluate the impact of intraoperative mupirocin irrigation on bacterial burden. METHODS: Sixteen patients with symmetric maxillary chronic rhinosinusitis were prospectively enrolled. After bilateral maxillary antrostomies, biopsies were taken of the maxillary sinus mucosa on both sides. In each patient, the right side was irrigated with 240 mL of normal saline (NS) and the left side was irrigated with 240 mL of NS mixed with 60 mg mupirocin. Repeat maxillary sinus mucosal biopsies were taken from each side 7 to 10 days postsurgery. Each biopsy was analyzed using quantitative polymerase chain reaction to determine the presence and relative amount of S. aureus. RESULTS: Mupirocin irrigations were found to significantly reduce the amount of S. aureus found within the maxillary sinus mucosa compared to NS alone. The average fold change between the pre- and posttreatment biopsies on the right and left was 9.05 and 97.42, respectively (p < 0.01). CONCLUSION: Intraoperative mupirocin irrigations significantly reduce the amount of S. aureus detected within the diseased sinus mucosa at up to 10 days postoperatively.


Assuntos
Antibacterianos/farmacologia , Seio Maxilar/microbiologia , Mupirocina/farmacologia , Lavagem Nasal/métodos , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/administração & dosagem , Doença Crônica , Feminino , Humanos , Masculino , Seio Maxilar/patologia , Pessoa de Meia-Idade , Mupirocina/administração & dosagem , Pólipos Nasais/microbiologia , Reação em Cadeia da Polimerase , Estudos Prospectivos , Rinite/microbiologia , Sinusite/microbiologia , Resultado do Tratamento
9.
Infect Immun ; 79(7): 2779-91, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21502589

RESUMO

The Porphyromonas gingivalis recombinant VimA can interact with the gingipains and several other proteins, including a sialidase. Sialylation can be involved in protein maturation; however, its role in virulence regulation in P. gingivalis is unknown. The three sialidase-related proteins in P. gingivalis showed the characteristic sialidase Asp signature motif (SXDXGXTW) and other unique domains. To evaluate the roles of the associated genes, randomly chosen P. gingivalis isogenic mutants created by allelic exchange and designated FLL401 (PG0778::ermF), FLL402 (PG1724::ermF), and FLL403 (PG0352::ermF-ermAM) were characterized. Similar to the wild-type strain, FLL402 and FLL403 displayed a black-pigmented phenotype in contrast to FLL401, which was not black pigmented. Sialidase activity in P. gingivalis FLL401 was reduced by approximately 70% in comparison to those in FLL402 and FLL403, which were reduced by approximately 42% and 5%, respectively. Although there were no changes in the expression of the gingipain genes, their activities were reduced by 60 to 90% in all the isogenic mutants compared to that for the wild type. Immunoreactive bands representing the catalytic domains for RgpA, RgpB, and Kgp were present in FLL402 and FLL403 but were missing in FLL401. While adhesion was decreased, the capacity for invasion of epithelial cells by the isogenic mutants was increased by 11 to 16% over that of the wild-type strain. Isogenic mutants defective in PG0778 and PG0352 were more sensitive to hydrogen peroxide than the wild type. Taken together, these results suggest that the P. gingivalis sialidase activity may be involved in regulating gingipain activity and other virulence factors and may be important in the pathogenesis of this organism.


Assuntos
Metaloendopeptidases/metabolismo , Neuraminidase/metabolismo , Porphyromonas gingivalis/patogenicidade , Fatores de Virulência/genética , Fatores de Virulência/metabolismo , Adesinas Bacterianas/genética , Adesinas Bacterianas/metabolismo , Aderência Bacteriana , Linhagem Celular Tumoral , Cisteína Endopeptidases/genética , Cisteína Endopeptidases/metabolismo , Eletroforese em Gel de Poliacrilamida , Cisteína Endopeptidases Gingipaínas , Células HeLa , Humanos , Immunoblotting , Metaloendopeptidases/genética , Mutação , Neuraminidase/genética , Porphyromonas gingivalis/enzimologia , Porphyromonas gingivalis/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Alinhamento de Sequência
10.
Int Forum Allergy Rhinol ; 1(5): 351-5, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22287465

RESUMO

BACKGROUND: Saline irrigations are routinely employed during endoscopic sinus surgery to remove mucous and debris from the sinus cavities. What is unknown is whether this results in a quantitative reduction in pathologic bacteria within the sinus mucosa. The objectives of this study were to quantify the amount of 5 different bacteria (Staphylococcus aureus, Haemophilus influenzae, Pseudomonas aeruginosa, coagulase-negative Staphylococcus (CNS), and Streptococcus pneumoniae) within the maxillary sinus and to determine the impact of saline irrigations on bacterial counts. METHODS: Twenty patients with chronic rhinosinusitis were prospectively enrolled. After bilateral maxillary antrostomies, biopsies were taken of the maxillary sinus mucosa prior to any irrigation. In each patient, the left maxillary sinus was then irrigated with 250 cc of normal saline (NS) with a pressurized pulse-irrigation device and the right side was irrigated with 250 cc of NS using a 30-cc syringe attached to a curved suction tip. Repeat maxillary sinus mucosal biopsies were then taken from each side. Each biopsy was analyzed using quantitative polymerase chain reaction to determine the presence and amount of each of the bacteria. RESULTS: Saline irrigations were found to significantly reduce the amount of S. aureus, P. aeruginosa, and S. pneumoniae found within the maxillary sinus mucosa. No difference was found for H. influenzae or CNS. No difference in bacterial load reduction was able to be shown between the pressurized saline flushes and manual saline rinse methods. CONCLUSION: Intraoperative saline irrigations are able to significantly reduce the amount of potentially pathogenic bacteria within the diseased sinus mucosa.


Assuntos
Carga Bacteriana/efeitos dos fármacos , Seio Maxilar/microbiologia , Mucosa Nasal/microbiologia , Rinite/microbiologia , Sinusite/microbiologia , Cloreto de Sódio/farmacologia , Doença Crônica , Feminino , Haemophilus influenzae/efeitos dos fármacos , Haemophilus influenzae/isolamento & purificação , Humanos , Masculino , Seio Maxilar/efeitos dos fármacos , Mucosa Nasal/efeitos dos fármacos , Reação em Cadeia da Polimerase , Estudos Prospectivos , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/isolamento & purificação , Cloreto de Sódio/administração & dosagem , Staphylococcus/efeitos dos fármacos , Staphylococcus/isolamento & purificação , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/isolamento & purificação , Streptococcus pneumoniae/efeitos dos fármacos , Streptococcus pneumoniae/isolamento & purificação , Irrigação Terapêutica/métodos
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