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1.
World J Microbiol Biotechnol ; 36(2): 25, 2020 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-31980951

RESUMO

In a search for novel therapeutic agents against pathogenic fungal species, Candida in addition to bacterial species, novel spinel nanoferrites were assayed against four pathogenic fungi isolated from different clinical samples of ear and skin infections: Aspergillus flavus, A. niger, A. terrus and A. fumigatus, four Candia species: Candida albicans, C. parapsilosis, C. krusei and C. tropicales, and four bacterial species: two Gram +ve: Bacillus subtilis and Streptococcus pyogenes, and two Gram -ve: Pseudomonas vulgaris and Escherichia coli. It was found that the assayed compounds displayed different levels of antifungal and antibacterial activities against all tested microorganisms. The antimicrobial potency depends on the method of synthesis of the nanoparticles and also on the microbial species.


Assuntos
Antibacterianos/síntese química , Antifúngicos/síntese química , Compostos Férricos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Antifúngicos/química , Antifúngicos/farmacologia , Compostos Férricos/química , Compostos Férricos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Nanopartículas , Relação Estrutura-Atividade
2.
J Photochem Photobiol B ; 202: 111723, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31785448

RESUMO

Cadmium-Bismuth microspheres (CdS-Bi2S3) were prepared by facile solvothermal method with polyvinylpyrrolidone (PVP) employed to control the morphology of CdS-Bi2S3. The product was characterized using X-ray diffraction (XRD), scanning electron microscope (SEM), diffuse reflectance UV-vis spectrophotometer and surface area of CdS-Bi2S3 was determined by BET analyzer. It was observed that CdS-Bi2S3 spheres exhibited good catalytic activity for the reduction of 4-nitrophenol. The photocatalytic application of CdS-Bi2S3 was evaluated for the photocatalytic degradation of environmental pollutants such as methyl orange, and methyl green under UV-visible light irradiation and it demonstrated good photocatalytic activity. Furthermore, we studied the antioxidant activity of CdS-Bi2S3 and it was observed that CdS-Bi2S3 showed antioxidant activity at all tested concentrations (5, 3 and 1 mg/mL). Antimicrobial activity of CdS-Bi2S3 microspheres was also studied for microbial control and the tested nanospheres proved to be exceptional antibacterial agent against tested Gram-positive and Gram-negative bacteria. CdS-Bi2S3 microspheres also exhibited significant cytotoxicity activity against HCT 116 (Human colon colorectal tumor) cell line. Our results indicate that CdS-Bi2S3 is good photocatalyst with several biological activities. The effective preparation method of CdS-Bi2S3 could be useful to design and fabricate the novel photocatalyst which may have several applications in the field of catalysis and in the medicine.


Assuntos
Antibacterianos/química , Antioxidantes/química , Luz , Microesferas , Poluentes Químicos da Água/química , Antibacterianos/síntese química , Antibacterianos/farmacologia , Compostos Azo/química , Bismuto/química , Cádmio/química , Catálise , Sobrevivência Celular/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Células HCT116 , Humanos , Testes de Sensibilidade Microbiana , Nitrofenóis/química , Oxigênio Singlete/química , Poluentes Químicos da Água/metabolismo
3.
Chem Commun (Camb) ; 56(3): 356-359, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31825398

RESUMO

A facile and scalable strategy for the quick library synthesis of linear-, hinged-, star-, and cyclic-polypeptides with broad-spectrum antimicrobial activity has been reported. The topologically nanoengineered polypeptides show superior antimicrobial activity against Gram-positive and Gram-negative bacteria and low toxicity, allowing screening of architectural polypeptides as mimics of host defense peptides for antimicrobials.


Assuntos
Anti-Infecciosos/síntese química , Peptídeos/química , Animais , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Camundongos , Testes de Sensibilidade Microbiana , Microscopia Confocal , Células NIH 3T3 , Nanotecnologia , Peptídeos/síntese química , Peptídeos/farmacologia
4.
J Photochem Photobiol B ; 202: 111706, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31775112

RESUMO

The noble metal such as Ag and Au doped CeO2 nanoparticles was successfully prepared by ionic liquid assisted hydrothermal method in the presence of Justicia adhatoda leaves extract and were used as an antibacterial and anticancer agent. The FT-IR and Raman spectrum exhibit the peaks at 460 and 464 cm-1 assigned to CeO stretching vibrations of NPs. The electron microscopic micrographs confirmed the spherical shaped morphology of prepared NPs. The insertion of Ag and Au ions into the CeO2 surface creates lattice defects the leads to reduce the band gap energy of Ag-Au/CeO2 at 3.15 eV. The XRD results suggested the average crystalline size of the silver­gold loaded CeO2 was 28 nm. From the elemental mapping images, we have visualized that existence and uniform distribution of Ag, Au, Ce, and O in the prepared nanomaterials. The antibacterial activity of unloaded and bimetal loaded CeO2 NPs was evaluated with Gram-positive and Gram-negative bacteria using disc diffusion assay. The AgAu loaded CeO2 NPs exhibited the highest zone of inhibition against E. coli and S. aureus strains when compared with pristine CeO2, Ag loaded CeO2, and Au loaded CeO2 NPs. In addition, the 100 µg mL-1 of CeO2, Ag/CeO2, Au/CeO2 and Ag-Au/CeO2 NPs exposed the 50, 51, 52 and 56% of anticancer activity against the HeLa cells respectively. Overall, this study concludes that the ionic liquid functionalized green synthesized bimetal loaded cerium oxide NPs showed potent antibacterial and anticancer activities.


Assuntos
Antibacterianos/química , Antineoplásicos/química , Líquidos Iônicos/química , Adhatoda/química , Nanopartículas Metálicas/química , Antibacterianos/síntese química , Antibacterianos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Cério/química , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Ouro/química , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Química Verde , Células HeLa , Humanos , Adhatoda/metabolismo , Nanopartículas Metálicas/toxicidade , Tamanho da Partícula , Extratos Vegetais/química , Folhas de Planta/química , Folhas de Planta/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Prata/química
5.
J Photochem Photobiol B ; 202: 111652, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31760374

RESUMO

The Biocompatibility and stability of nanoparticles using plants have been widely investigated due to its applications in the biomedical industry. Currently, there is a growing interest in nanoparticles in bone remodelling. Artemisia annua is an herbal plant commonly used in the treatment of various ailments. This study investigated the zinc oxide nanoparticles (ZnO NPs) using the green synthesis technique from A. annua and the effects of A. annua ZnO-NPs on osteoblast differentiation and inhibition of osteoclast formation. The formulated ZnO-NPs from A. annua were characterized by using various spectroscopic and microscopic methods Fourier transform-infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), X-ray diffraction (XRD), and UV-Visible spectroscopy. The disc diffusion method was adopted to test the antimicrobial efficacy of ZnO-NPs. The viability of MG-63 cells were assayed by MTT test and Osteogenic-related assays like Real-time PCR and Mineralization assay were adopted to determine the effects of A. annua ZnO-NPs on the multiplication and differentiation of human osteoblast-like MG-63 cells. The characterization of A. annua ZnO-NPs revealed the crystalline nature with high zinc content and the presence of bioactive compounds from A. annua extract. The synthesized A. annua ZnO-NPs indicate significant antimicrobial potential. Besides, A. annua ZnO-NPs enhanced the proliferation, differentiation, and mineralization without causing significant cytotoxic impact on MG-63 cells. These effects indicate that A. annua ZnO-NPs can both stimulate bone formation via the differentiation of MG-63 cells. Hence, it was concluded that A. annua ZnO-NPs can be a promising agent for the treatment of bone deformities and bone-related diseases, however further research also required to explore the clear mechanism of A. annua ZnO-NPs in the formation and differentiation of MG-63 cells.


Assuntos
Artemisia annua/química , Diferenciação Celular , Proliferação de Células , Nanopartículas Metálicas/química , Anti-Infecciosos/síntese química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Artemisia annua/metabolismo , Cálcio/metabolismo , Candida/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Química Verde , Humanos , Nanopartículas Metálicas/toxicidade , Osteoblastos/citologia , Osteoblastos/metabolismo , Osteogênese/efeitos dos fármacos , Casca de Planta/química , Casca de Planta/metabolismo , Extratos Vegetais/química , Óxido de Zinco/química
6.
J Photochem Photobiol B ; 202: 111729, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31835161

RESUMO

Bacterial pathogenicity is becoming a major cause of morbidity and mortality around the globe. Researchers are tirelessly finding solutions to cure or prevent infections caused by bacterial pathogens. Nanotechnology is a fast-growing area of research, effectively influencing and preventing bacterial growth. Nanoparticles (NPs) of silver, copper and gold are being used to kill bacterial pathogens in the past years but the toxicity of NPs at higher concentrations remains a major problem. Therefore, in the present study, Co3O4@ZrO2 (CoZ) core/shell NPs were synthesized using a simple sol-gel method. The synthesized NPs were characterized using different analytical techniques revealing the absorption bands at 456 and 277 nm with crystalline size of ~600 nm core/shell. The functional groups and oxidation states were characterized using FTIR analysis. Further bactericidal properties of core/shell of Co3O4@ZrO2 NPs were tested against Gram negative (Escherichia coli, Pseudomonas aeruginosa) and Gram positive (Staphylococcus aureus, Bacillus subitilis) pathogens. The core/shell CoZ NPs showed maximum growth inhibitions against S. aureus and P. aeruginosa. At the highest concentration of 200 µg/mL, the maximum zone of inhibition was observed. The synthesized CoZ NPs was also subjected to photocatalytic degradation of rhodamine B in 180 min under visible light irradiation. The present study could be an innovative and efficient research for both biomedical and wastewater treatment applications.


Assuntos
Nanopartículas Metálicas/química , Rodaminas/química , Catálise , Cobalto/química , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Luz , Nanopartículas Metálicas/toxicidade , Óxidos/química , Tamanho da Partícula , Fotólise/efeitos da radiação , Zircônio/química
7.
Pol Merkur Lekarski ; 47(281): 197-202, 2019 Nov 29.
Artigo em Polonês | MEDLINE | ID: mdl-31812976

RESUMO

Biofilm is a form of bacterial life in extreme environmental conditions. The known structure and functions of biofilm indicate that it is one of the most widespread and most successful life forms on earth. The quorum sensing (QS) system plays a key role in biofilm because it is a mechanism by which bacteria regulate the gene expression profile according to the size of the microbial population, causing the formation of different forms of biofilm. The QS includes the auto-inducer-1 (AI- 1) system, which uses N-acyl-homoserine lactones as a signaling factor in the formation of biofilm by Acinetobacter baumannii and Pseudomonas aeruginosa, and the auto-inducer-2 (AI-2) system identified as furanosyl borate diester present in Gram-positive and Gram-negative bacteria. Antimicrobial proteins (AMPs) have a natural antibacterial effect, which are produced by eukaryocytes and prokaryocytes, and have the ability to form pores in the bacterial cell membrane or interfere with its function. On the other hand, biofilm degrading enzymes - DNase I, alpha-amylase and dispersin B - reduce the weight of exopolysaccharides (EPS) and the number of cells in the biofilm. Natural compounds that inhibit the formation of bacterial biofilm have been distinguished, so-called QS inhibitors (QSI) and which "quench" active process (QSQ). In turn, genetic diversification of microorganisms in biofilm is largely responsible for shaping antibiotic resistance. The combined use of antibiotics with nanoparticles seems to be the most promising therapeutic option for bacterial biofilm. Silver nanoparticles with citrate in combination with aztreonam have been shown to have significant biofilm-destroying efficacy for Pseudomonas aeruginosa, and selenium nanoparticles used together with ampicillin, oxacillin and penicillin in 94% inhibited and interrupted the MRSA (methicillin-resistent) biofilm. Research on biofilm control is very advanced and will soon be subject to clinical evaluation.


Assuntos
Biofilmes , Antibacterianos , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Nanopartículas Metálicas , Pseudomonas aeruginosa , Prata
8.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 27(6): 1774-1778, 2019 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-31839037

RESUMO

OBJECTIVE: To investigate the clinical characteristics, etiology and drug susceptibility of bacterial bloodstream infections in acute leukemia(AL) patients. METHODS: Clinical data, etiology and drug susceptibility of acute leukemia patients with bacterial bloodstream infections from April 2009 to April 2018 were retrospectively analyzed. RESULTS: A total of 376 strains were isolated, 76.9% was Gram-negative bacterial and 23.1% was Gram-positive bacteria. Escherichia coli, Pseudomonas aeruginosa and Klebsiella pneumoniae were listed as the top three of Gram-negative bacteria. The susceptibility of Escherichia coli to the tigacycline, imipenem and meropenem was 100.0%, 98.2% and 98.1%, respectively. The susceptibility of Klebsiella pneumoniae to the tigacycline, imipenem and meropenem were 100.0%, 98.3% and 94.4%, respectively. The adjustment rate for initial use of carbopenems was 3.8%, while the adjustment rate for initial use of noncarbopenems was 74.3% in patients with main Gram-negative bacterial blood stream infection. The susceptibility of Gram-positive bacteria to glycopeptide antibiotics, linezolid and tigacycline was 100.0%. CONCLUSION: Gram-negative bacteria is the majority type of bacteria in AL patients with bacteria blood stream infections. The susceptibility of Gram-negative bacteria to the carbapenems is high, and the treatment adjustment rate is obviously low. The glycopeptide, linezolid and tigacycline are effective for Gram-positive bacteria infections..


Assuntos
Bacteriemia , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Humanos , Testes de Sensibilidade Microbiana , Estudos Retrospectivos
10.
J Photochem Photobiol B ; 200: 111622, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31678034

RESUMO

Seaweeds are considered to be one of the richest bio-reserves, comprising of numerous bioactive compounds with versatile properties and multiple activities. The present study examined the antibacterial activity of two types of seaweeds, Ulva lactuca (green) and Stoechospermum marginatum (brown) collected from Oman Coastal region against five multidrug-resistant bacteria. The aqueous extracts of the seaweeds showed better antibacterial activity compared to methanol extracts. The results of the antibacterial assay revealed the excellent inhibitory effects of U.lactuca with the maximum activity against E.coli(8 mm) followed by K.pneumonia(4 mm) and S.typhi(2 mm). S.marginatum formed a clear zone of inhibition only against E.coli(3 mm).The major phytochemical constituents identified in both the types of seaweeds were Alkaloids, Terpenoids, Saponins, Flavonoids, and Steroids. Fourier transform infrared spectroscopy (FTIR) results confirmed the presence of alcoholic/phenolic groups, and amide groups in the seaweed extracts. Gas chromatography-mass spectrometry (GC-MS) results evidenced the presence of bioactive compounds such as 5-Octadecenal, 1-Tricosanol, Neophytadiene, Lactaropallidin, Phytol, Fenretinide, Lucenin, Vincadifformine in U.lactuca. Additionally, U.lactuca displayed better antioxidant activity (33.05%) in the DPPH free radical scavenging activity test compared to the S.marginatum (21.51%). Thus, the green seaweed U.lactuca could be considered as a potential source of natural antioxidant and antibacterial agents for food and pharmaceutical products.


Assuntos
Antibacterianos/química , Feófitas/química , Extratos Vegetais/química , Ulva/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Antioxidantes/química , Bioprospecção , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Feófitas/metabolismo , Ulva/metabolismo
11.
J Photochem Photobiol B ; 200: 111645, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31671371

RESUMO

Antimicrobial peptide W3R6 was derived from chensinin-1b and showed potential as a novel antibiotics. However, W3R6 was susceptible to protease cleavage, which limited its therapeutic application. To improve the proteolytic resistance of W3R6, D-amino acids were incorporated into its sequence by specific amino acid substitution or whole sequence substitution according to the specificity of the cleavage site. In this study, partially substituted analog D-Arg-W3R6 and completely substituted D-enantiomer D-W3R6 were synthesized. The resistance of D-Arg-W3R6 and D-W3R6 to cleavage by the tested protease increased, particularly of D-W3R6. The antimicrobial activity of D-Arg-W3R6 was almost the same as that of the parent peptide W3R6, but the antimicrobial activity of D-W3R6 was slightly decreased. The hemolytic activity of both D-Arg-W3R6 and D-W3R6 was negligible. The CD spectrum of D-W3R6 exhibited symmetry with that of W3R6 in a membrane-mimetic environment. The membrane interaction between the D-amino acid substituted analogs and a real/mimic bacterial cell membrane was examined. The outer membrane depolarization, inner membrane permeability and dye leakage in three types of liposomes treated with D-Arg-W3R6 and D-W3R6 were not obviously different from W3R6, which could be due to the similar physical and chemical properties. In addition, these three peptides showed the binding ability with LPS micelles detected by ITC, and their ability to disrupt the LPS micelles was examined by DLS experiment and even neutralize the surface negative charge of E. coli cells. These results suggest that D-Arg-W3R6 is a promising antibiotic molecule.


Assuntos
Aminoácidos/química , Anti-Infecciosos/química , Peptídeos Catiônicos Antimicrobianos/química , Anti-Infecciosos/síntese química , Anti-Infecciosos/farmacologia , Peptídeos Catiônicos Antimicrobianos/síntese química , Peptídeos Catiônicos Antimicrobianos/farmacologia , Parede Celular/química , Parede Celular/efeitos dos fármacos , Parede Celular/metabolismo , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Humanos , Lipossomos/química , Lipossomos/metabolismo , Peptídeos/química , Permeabilidade/efeitos dos fármacos , Estabilidade Proteica
12.
J Photochem Photobiol B ; 201: 111670, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31706087

RESUMO

Synthesis of nanoparticles using plant sources as reducing agent has become important, as physical and chemical methods are costlier and affects environment. Hence it is important to develop environment friendly nanoparticle synthesis by avoiding the use of toxic chemicals. The present study aimed to synthesize silver nanoparticles (Ag Nps) and gold nanoparticles (AuNps) using Musa acuminata colla flower and its pharmaceutical activity against extended spectrum beta-lactamase (ESBL) gene producing bacteria and anticancer efficacy. The synthesized Ag and Au NPs were analysed by means of UV-Vis, FTIR, XRD,SEM and EDAX evidenced the bioreduction of Ag+ ions to Ag0 and Au3+ ions to Au0 respectively. Both nanoparticles and flower extracts were studied for antibacterial activity of ESBL gene producing bacteria by disc diffusion and microdilution (Resazurin) method. In vitro anticancer efficacy (MCF-7) and toxicity (VERO) of AgNPs, AuNPs, aqueous extract and ethanol extract of flowers were performed by MTT assay. IC50 value for DPPH analysis was at 390 µg and 460 µg for ethanol and aqueous extract respectively. Total antioxidant content was found be 740 µg/mg and 460 µg/mg for ethanol and aqueous extract. GCMS analysis authenticated the existence of the compounds namely, 9,12-octadecadienoic acid(z,z)- and n-hexadecanoic acid in the crude extract of the samples. Among the samples, AgNPs had best antibacterial activity. AgNPs and AuNPs were confirmed by colour change to reddish brown and ruby red. Further ƛmax were obtained at 474 and 540 nm by UV - visible spectrum. SEM analysis revealed the particle size ranges from 12.6 to 15.7 nm for silver and 10.1 to 15.6 nm for gold nanoparticles. The EDAX spectrum shows a strong signal for elemental Ag and Au at ~ 3 keV and 1.5 keV. The XRD patterns for silver and gold nanoparticles at 36.701, 42.900, 63.281 and 76.398 corresponding to the lattice planes 2.4467, 2.1064, 1.46839, 1.24564 nm and 27.32, 36.7228, 39.56, 42.888, 63.253, 63.253, 65.02 and 76.383 corresponding to the lattice planes 3.262, 2.44530, 2.276, 2.1070, 1.46897, 1.4332 and 1.24585 nm. The IC50 values for MCF-7 and VERO cells were 30.0 µg/ml and 55.0 µg/ml respectively.


Assuntos
Antibacterianos/química , Antineoplásicos/química , Ouro/química , Musa/química , Prata/química , Animais , Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Antioxidantes/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Flores/química , Flores/metabolismo , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Química Verde , Humanos , Nanopartículas Metálicas/química , Nanopartículas Metálicas/toxicidade , Musa/metabolismo , Extratos Vegetais/química , Células Vero
13.
Medicine (Baltimore) ; 98(44): e17751, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31689830

RESUMO

Maternal bacterial sepsis during pregnancy and the postpartum period is a common cause of maternal mortality and fetal morbidity and mortality. This study was performed to analyze perinatal prognosis and related factors of maternal bacterial sepsis in west China.We conducted a cross-sectional study of pregnant women with bacterial sepsis who were admitted into a tertiary care center in western China between 2011and 2015. Data from these cases were collected and analyzed.Eighty six women were identified with bacterial sepsis in our hospital, and the incidence of maternal bacterial sepsis was 1.7 per 1000 maternities, the incidence of septic shock was 1.8 per 10,000 maternities, and 1 maternal death occurred. Among the 86 pregnant women with bacterial sepsis, genital tract infection was the most common source of infection (41/86, 47.7%). The most common bacteria in the Gram-positive bacteria group was Listeria monocytogenes and in the Gram-negative bacteria group was Escherichia coli. The premature delivery rate (65.7%) was substantially higher in the Gram-negative bacteria group (P = .011), and the miscarriage rate (31.3%) was higher in the Gram-positive bacteria group (P = .042). The fetal/neonatal mortality rate was 20% (21/105) and higher in the Gram-positive bacteria group (P = .008), and the infant mortality rate in 1 year was 7.1% (6/84).Bacterial sepsis remains an alarming cause of both maternal and fetal morbidity and mortality, and infant mortality. Key treatment involves a multi-disciplinary group of clinicians with experience in all aspects of the care of pregnant women with sepsis and early initiation of appropriate antibiotics according to the type of bacterial infection. The effect of maternal sepsis on long-term fetal outcome should be investigated.


Assuntos
Bactérias Gram-Negativas , Bactérias Gram-Positivas , Complicações Infecciosas na Gravidez/mortalidade , Infecções do Sistema Genital/mortalidade , Sepse/mortalidade , Aborto Espontâneo/microbiologia , Aborto Espontâneo/mortalidade , Adulto , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Incidência , Lactente , Mortalidade Infantil , Recém-Nascido , Mortalidade Materna , Gravidez , Complicações Infecciosas na Gravidez/microbiologia , Infecções do Sistema Genital/microbiologia , Sepse/microbiologia
14.
J Photochem Photobiol B ; 201: 111649, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31710925

RESUMO

In the present systematic study, silver nanoparticles have been synthesized using the fruits of Alpinia nigra. Apart from the presence of saponins, glycosides, alkaloids, steroids, the extract of A. nigra fruits are rich in polyphenols. The Total Flavonoid and Phenol Content of A. nigra fruits extract is 718 mgRE/g extract and 74.9 mgGAE/g extract respectively. The formation of the nanoparticles was validated through characterization techniques like UV-Vis spectroscopy, X- ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Energy dispersive X-ray spectroscopy (EDX). The spherical shape of silver nanoparticles is observed in Transmission Electron Microscopy (TEM) images. The average particle size of the silver nanoparticles is 6 nm. The biomolecules of the fruit extract played the dual role of reducing and capping agents which is evident from Fourier Transform Infrared (FTIR) spectrometer and Scanning Electron Microscopy (SEM) image analysis. The A. nigra capped silver nanoparticles exhibited promising antimicrobial activity against gram negative bacteria Klebsiella pneumoniae, gram positive bacteria Staphylococcus aureus and the pathogenic fungus, Candida albicans. Amongst the three pathogens, Klebsiella pneumoniae is the most susceptible to silver nanoparticles. Furthermore, the nanoparticles efficiently catalysed the degradation of the anthropogenic dyes Methyl orange, Rhodamine B and Orange G in the presence of sunlight. The photocatalytic degradation process follows the pseudo-first order kinetics. These results confirm that the silver nanoparticles can be efficiently synthesized via a green route using A. nigra fruits with applications as antimicrobial and catalytic agents.


Assuntos
Alpinia/química , Anti-Infecciosos/síntese química , Nanopartículas Metálicas/química , Prata/química , Alpinia/metabolismo , Anti-Infecciosos/farmacologia , Compostos Azo/química , Catálise , Corantes/química , Frutas/química , Frutas/metabolismo , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Química Verde , Nanopartículas Metálicas/toxicidade , Tamanho da Partícula , Extratos Vegetais/química , Luz Solar
15.
J Photochem Photobiol B ; 201: 111683, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31710928

RESUMO

In recent years dendrimers have fascinated the investigators towards targeted drug delivery because of their versatile framework and exhibit immense potentiality in entrapping drug moieties through host-guest interactions and serve as a promising vector in biological applications. The current investigation is focused on developing pegylated citric acid cefotaxime dendrimers through the divergent method and its characterization through spectroscopic, microscopic, thermal and microscopic techniques. Among the spectroscopic techniques, 1H NMR and 13C NMR elucidated the key functional groups at various chemical shifts while ESI-MS pointed out the molecular weight of cefotaxime sodium in various generations. Similarly, FTIR, DSC, and AFM investigations detailed that the generations are devoid of incompatibilities, structural deformities and can be opted for targeted drug delivery. The drug entrapment studies and in-vitro drug release studies highlight CFTX G5 containing 92.4% entrapment efficacy and 83.8% drug release in 48 h and specifies a sustain release characteristics. In connection to the above, the in-vivo studies reveal a potent antibacterial activity against various gram-positive and gram-negative microorganisms with a decreased hemolysis and cytotoxicity effects and reflect a high margin of safety regarding pegylated CFTX dendrimers. Further, the antibacterial activities are supported through confocal microscopy that clarified the cellular uptake of dendritic molecules and their internalization.


Assuntos
Cefotaxima/química , Ácido Cítrico/química , Dendrímeros/química , Nanoestruturas/química , Células A549 , Antibacterianos/química , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Cefotaxima/metabolismo , Cefotaxima/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Meia-Vida , Hemólise/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Nanoestruturas/toxicidade , Polietilenoglicóis/química
16.
Klin Lab Diagn ; 64(10): 632-634, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31742958

RESUMO

Current methods of biofilm imaging do not support a differentiated assessment of its composition, since it is not possible to establish a substrate stained with crystal violet, as this dye can form complexes with both intracellular and extracellular structures. This approach does not adequately assess the anti-biofilm effects of drugs, while the results of studying the interaction of drugs with biofilm components can ensure their most correct choice. The aim of investigation was to study the possibility of applying the original modification of the current method to determine the ratio of the cellular part and the matrix of biofilms of gram-positive microorganisms. The biofilm components were analyzed using a two-step approach, when prepared biofilms of gram-positive microorganisms were stained with crystal violet for 5 minutes, followed by fixing the dye in bacterial cells with iodine solution, and then the colored products were dissolved with 95% alcohol: matrix components for 1 minute, total biofilm for 15 minutes, after which the composition of biofilms was estimated by the formula: M=(OP1/OP15)×100, Kb=100-M, where M is the proportion of the matrix,%; Kb - the proportion of the cellular component,%; OP1 - optical density of samples, when alcohol was allowed to dissolve the colored product for no more than 1 minute; OP15 - was the optical density of samples, when alcohol is allowed to dissolve the colored product for 15 minutes. It was shown that in the composition of the biofilm formed by the collection strain, the proportion of the matrix was 13.2%, and the cellular component accounted for 86.8%. When the same strain cultivated in the presence of an antibiotic, an increase in the biofilm matrix was observed, which is probably due to the compensatory response of the microorganism to the action of the antibiotic. The proposed approach to the study of biofilms makes it possible to evaluate its component composition. Obtaining additional information in this way can provide, inter alia, an increase in the effectiveness of antimicrobial therapy while reducing the study time.


Assuntos
Biofilmes , Bactérias Gram-Positivas/classificação , Coloração e Rotulagem
17.
BMC Complement Altern Med ; 19(1): 279, 2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31640666

RESUMO

BACKGROUND: Rapid emergence of multidrug resistant (MDR) organisms in hospital and community settings often result into treatment failure, thus leading the clinicians with fewer treatment options. Cyathea gigantea, an ethnomedicinally important fern used in cuts and wound infections. So, if this medicinal plant is used in treating the MDR infections then it might bring certain relief in future treatment options. METHODS: Antibacterial activity of C. gigantea against MDR bacteria was assed using well diffusion and broth microdilution methods to determine the diameters of growth inhibition zones, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). Synergistic activity was also determined with the conventional antibiotics by disc diffusion method followed by FIC index of each of the tested antibiotic was calculated. The active extract was then subjected to fractionation by column chromatography and antibacterial activity was done with each of the collected fractions. RESULTS: Crude extract of C. gigantea was found to be active against all the tested organisms. The MIC was 200 µg/ml against Gram-positive i.e., Staphylococcus aureus ATCC 25923 and 400 µg/ml against Gram-negative i.e., Escherichia coli ATCC 25922 and Pseudomonas aeruginosa PAO1, while the MBC was 400 µg/ml in case of Gram-positive and 800 µg/ml for Gram-negative. The synergistic activity revealed that the plant extract increased the antibacterial property of the studied antibiotics and the FIC index showed that significant synergistic activity was shown by ciprofloxacin followed by tetracycline, ampicillin and oxacillin. Antibacterial activity with the fractionated extract showed that the FR II, FR III and FR IV were active against both Gram-positive and Gram-negative bacteria, whereas FR I, FR V and FR VI did not show antibacterial property against any of the tested bacteria. CONCLUSIONS: Extracts of C. gigantea was found active against both selected Gram-positive and Gram-negative organisms and thus offers the scientific basis for the traditional use of the fern. The present study also provides the basis for future study to validate the possible use against multidrug resistant organisms.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla , Extratos Vegetais/farmacologia , Traqueófitas/química , Antibacterianos/química , Infecções Bacterianas/microbiologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Folhas de Planta/química , Plantas Medicinais/química
18.
Orv Hetil ; 160(41): 1623-1632, 2019 Oct.
Artigo em Húngaro | MEDLINE | ID: mdl-31587580

RESUMO

Introduction: Previous data showed bacterial infections among diabetic patients to be more serious and frequent, with higher mortality rates in comparison with non-diabetics. Recent investigations, however, are contradictory. Aim: The goal of our prospective, observational study was to compare patients hospitalized on a general medical ward due to community-acquired bacterial infections with type 2 diabetes mellitus (T2DM) to those of non-diabetics (K) by 1) infection localization, 2) spectrum of pathogens, 3) three-month mortality rates. Method: Patients were consecutively involved (T2DM: n = 205, K: n = 202). We characterized the infections, clinical parameters, mortalities of the two groups, and matched them to international data. Results: No difference regarding clinical details of the groups were found except for glycemic parameters and BMI. In the T2DM group the skin- and soft tissue- (37.1%), in the K patients respiratory infections (37.1%) were the most common, followed by urinary ones (31.2% and 31.7%, respectively). Skin- and soft tissue infection incidence among T2DM subjects were higher compared to international results (37.1% vs. 16%). Co-presence of Gram positive and Gram negative bacteria in the skin- and soft tissue infections (23/76 vs. 5/46, p = 0.0149), and polymicrobial origin in the urinary tract infections (34.0% vs. 15.1%, p = 0.0335) were found to be more frequent in T2DM than in K. No difference regarding mortality rates were detected. In T2DM the skin- and soft tissue while in the K group the respiratory infections had the most death counts. Conclusions: We found higher rates of skin- and soft tissue infections among T2DM patients hospitalized on a general medical ward compared to international data. In total we did not find difference regarding three-month mortality between the groups. Our results highlight the importance of primary prevention and shows its inadequacy concerning skin and soft tissue infections among type 2 diabetics in Hungary. Orv Hetil. 2019; 160(41): 1623-1632.


Assuntos
Infecções Bacterianas/diagnóstico , Infecções Comunitárias Adquiridas/microbiologia , Diabetes Mellitus Tipo 2/complicações , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Positivas/isolamento & purificação , Infecções dos Tecidos Moles/microbiologia , Infecções Urinárias/microbiologia , Adulto , Idoso , Infecções Bacterianas/epidemiologia , Infecções Comunitárias Adquiridas/epidemiologia , Diabetes Mellitus Tipo 2/microbiologia , Feminino , Humanos , Hungria/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Infecções dos Tecidos Moles/epidemiologia , Infecções Urinárias/epidemiologia
19.
Chem Biodivers ; 16(12): e1900373, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31654549

RESUMO

Phytochemicals, which are commonly found at different levels in many medicinal plants, are natural strong antioxidants used in traditional medicine. In this research, determination of differences of phytochemical compositions and biological properties were aimed as periodically (pre-, full and post flowering) and daily (6 am, 1 pm and 8 pm) in Achillea gypsicola Hub.-Mor. The volatile oils belonging to A. gypsicola were obtained by hydrodistillation and analyzed by gas chromatography-flame ionization detection (GC-FID) and gas chromatography-mass spectrometry (GC/MS). The antimicrobial activities of the volatile oils were determined with disc diffusion method. The microdilution method was used to determine minimum inhibitory concentration (MIC). Total phenolic and flavonoid contents were determined by spectrophotometric methods and antioxidant capacities were evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical, reducing power (RP) and metal chelating activity (MCA) assay. In addition, the phenolic acid and flavonoid compositions were evaluated by reversed phase-high-performance liquid chromatography (RP-HPLC). This study presented a comprehensive report for the first time on evaluation of the phytochemical composition and the biological properties of A. gypsicola at different phenological stages. Thirty-two compounds, containing the major component as camphor, 1,8-cineole and borneol, were detected. Designated harvest time for the highest yield of volatile oils was found to be at full flowering stage-1 pm. It has been observed that the volatile oil composition changes periodically and even daily. Also, in this research, menthol and menthone were found as the composition of volatile oil in Achillea species for the first time. Full flowering stage was found as the richest period in terms of phenolic acid and flavonoid compositions of A. gypsicola for the first time. The species examined in this research showed a high antioxidant and antimicrobial activity in comparison to other studies with Achillea species. The volatile oils exhibited high performances with range of inhibition zones (8.3-42.3 mm) and minimum inhibitory concentration values (2.25-144 µg/ml). Besides, a high correlation between antioxidant activity and phenolic content of A. gypsicola was found. These results suggest that A. gypsicola can be used as a safe source in the cosmetic, food and pharmaceutical industries.


Assuntos
Achillea/química , Óleos Voláteis/química , Compostos Fitoquímicos/química , Achillea/metabolismo , Antioxidantes/química , Cromatografia Líquida de Alta Pressão , Cromatografia de Fase Reversa , Flavonoides/análise , Flavonoides/química , Flavonoides/farmacologia , Flores/química , Flores/metabolismo , Fungos/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Óleos Voláteis/farmacologia , Fenóis/análise , Fenóis/química , Fenóis/farmacologia , Compostos Fitoquímicos/farmacologia , Análise de Componente Principal
20.
Chem Biodivers ; 16(12): e1900461, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31557406

RESUMO

The discovery of new antimicrobial agents is extremely needed to overcome multidrug-resistant bacterial and tuberculosis infections. In the present study, eight novel substituted urea derivatives (10a-10h) containing disulfide bond were designed, synthesized and screened for their in vitro antimicrobial activities on standard strains of Gram-positive and Gram-negative bacteria as well as on Mycobacterium tuberculosis. According to the obtained results, antibacterial effects of the compounds were found to be considerably better than their antimycobacterial activities along with their weak cytotoxic effects. Molecular docking studies were performed to gain insights into the antibacterial activity mechanism of the synthesized compounds. The interactions and the orientation of compound 10a (1,1'-((disulfanediylbis(methylene))bis(2,1-phenylene))bis(3-phenylurea)) were found to be highly similar to the original ligand within the binding pocket E. faecalis ß-ketoacyl acyl carrier protein synthase III (FabH). Finally, a theoretical study was established to predict the physicochemical properties of the compounds.


Assuntos
Antibacterianos/síntese química , Dissulfetos/química , Ureia/análogos & derivados , 3-Oxoacil-(Proteína de Transporte de Acila) Sintase/química , 3-Oxoacil-(Proteína de Transporte de Acila) Sintase/metabolismo , Animais , Antibacterianos/farmacologia , Antituberculosos/síntese química , Antituberculosos/farmacologia , Sítios de Ligação , Sobrevivência Celular/efeitos dos fármacos , Enterococcus faecalis/enzimologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Camundongos , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Estrutura Terciária de Proteína , Células RAW 264.7 , Relação Estrutura-Atividade , Ureia/farmacologia
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