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1.
Rev Peru Med Exp Salud Publica ; 38(2): 313-317, 2021.
Artigo em Espanhol, Inglês | MEDLINE | ID: mdl-34468582

RESUMO

In order to determine the frequency of community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) isolates and to describe the antimicrobial resistance pattern and genotype, a cross-sectional study was conducted in 2017 at the Hospital Nacional Cayetano Heredia in Lima, Peru. We found a MRSA prevalence of 46.1% in the 115 analyzed S. aureus isolates; most were reported from different secretions (26.4%) and blood (18.9%). We found high co-resistance (>75%) to clindamycin, erythromycin, gentamicin and ciprofloxacin. Regarding SSCmec typification, most of the isolates were identified as hospital-acquired MRSA (HA-MRSA) and a minority of them as CA-MRSA (2.6%). Despite its low prevalence when compared to other Latin American countries (27%), epidemiological surveillance is recommended to control local CA-MRSA dissemination.


Assuntos
Infecções Comunitárias Adquiridas , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Antibacterianos/uso terapêutico , Infecções Comunitárias Adquiridas/tratamento farmacológico , Infecções Comunitárias Adquiridas/epidemiologia , Estudos Transversais , Humanos , Staphylococcus aureus Resistente à Meticilina/genética , Testes de Sensibilidade Microbiana , Peru/epidemiologia , Infecções Estafilocócicas/epidemiologia , Staphylococcus aureus , Centros de Atenção Terciária
2.
Mater Sci Eng C Mater Biol Appl ; 128: 112266, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34474825

RESUMO

The precipitates in Ti-Ag alloy made an important contribution to antibacterial activity. In order to study this specific effects, Ti-Ag samples with different forms of precipitates were produced by powder metallurgy and ingot metallurgy followed by heat treatment: Ti-Ag(T4) with no precipitate, Ti-Ag(as-cast) and Ti-Ag(T6) with Ti2Ag and Ti-Ag(PM) with Ti2Ag and Ag-rich phase. Microstructure was analyzed by scanning electronic microscope (SEM), and the antibacterial effects, expression of reactive oxygen species (ROS), protein leakage and biocompatibility were investigated by plate count method, staining technology and cell test. The antibacterial ability was in the following order from low to high: Ti-Ag(T4) < Ti-Ag(as-cast) < Ti-Ag(T6) < Ti-Ag(PM). It was elucidated that Ag-containing phase was the major controlling factor of Ti-Ag antibacterial property and Ti-Ag(PM) with micro-size Ti2Ag and Ag-rich phase exhibited high antibacterial activity. It was proposed that the existence of Ag-containing phases induced high expression of ROS in bacteria, which destroyed the homeostasis of the bacteria and eventually leads to the rupture of the bacterial membrane. Cell test indicated that Ti-Ag samples had no adverse effect on cells and had good biocompatibility.


Assuntos
Ligas , Staphylococcus aureus , Ligas/farmacologia , Antibacterianos/farmacologia , Teste de Materiais , Metalurgia , Titânio/farmacologia
3.
Mater Sci Eng C Mater Biol Appl ; 128: 112290, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34474841

RESUMO

Antimicrobial Polyvinyl chloride (PVC) was obtained by covalent bonding of zinc oxide nanoparticles, which have gained important achievements in antimicrobial fields because of their auspicious properties. This was achieved by grafting mercaptopropyltrimethoxysilane onto PVC, followed by the growth of zinc oxide nanoparticles covalently bonded on the polymer surface. In this study, the relationship between the physicochemical features of modified-surface PVC and antimicrobial activity on Staphylococcus aureus and Candida albicans was investigated. Zinc oxide with controllable morphologies (rods, rod flowers, and petal flowers) was synthesized on the polymer surface by tuning merely base-type and concentration using a hydrothermal process. The antimicrobial activity was more pronounced for rod flower morphology, because of their differences in microscopic parameters such as specific Zn-polar planes. This work provides an important hint for the safe use of PVC for biomedical devices by the structure surface tuning without injuring polymer bulk properties and a reduced risk of the covalently bonded nanoparticle dispersion in the host and the environment.


Assuntos
Anti-Infecciosos , Nanopartículas , Óxido de Zinco , Cloreto de Polivinila , Staphylococcus aureus , Óxido de Zinco/farmacologia
4.
Mater Sci Eng C Mater Biol Appl ; 128: 112294, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34474845

RESUMO

In the present study, new-layered inorganic/organic hybrid of silver/talc nanocomposites (Ag/Tlc-NPs) and its chitosan-capped derivative (Ag/Tlc/Csn NCs) were biochemically synthesized utilizing Lawsonia inermis L. extract. The silver nanoparticles (Ag NPs) were synthesized employing green method on the exterior surface layer of talc mineral as a solid substrate. The negatively charged surface layer of talc might function as templates and can attract the chitosan cations from a solution to yield a layered hybrid structure, whose inorganic phase is formed by Si-O-Ag bonds. Our results revealed that Ag NPs were formed on the exterior surface of talc with a diameter with size of 124-215 nm. In addition, cytotoxicity, in vitro antibacterial activity, and clinical effects of wound-healing ointments containing talc were investigated. The results implied the successful synthesis of Ag/Tlc/Csn NCs using the extract. The structures were safe up to 0.50 mg/mL. In vitro studies confirmed antioxidant and antibacterial properties of Ag/Tlc/Csn NCs. In sum, our findings showed that the ointments improve wound healing process by inducing an anti-inflammatory M2 phenotype and bFGF, CD206, collagen1A, and IL-10 production that causes fibroblast migration and wound closure through influencing M2 macrophage. Ag/Tlc/Csn is suggested to be taken into consideration as a medical combination for improving infected wound healing and as a promising agent for clinical administration.


Assuntos
Quitosana , Lawsonia (Planta) , Nanopartículas Metálicas , Nanocompostos , Aceleração , Antibacterianos/farmacologia , Pseudomonas aeruginosa , Prata , Staphylococcus aureus , Eletricidade Estática , Talco , Cicatrização
5.
Mater Sci Eng C Mater Biol Appl ; 128: 112296, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34474847

RESUMO

Hydroxyapatite is widely utilized for different biomedical applications because of its outstanding biocompatibility and bioactivity. Cuttlefish bones, which are available aplenty, are both inexpensive and eco-friendly sources for calcium carbonate. In the present study, cuttlefish bones-derived HAp nanorods have been utilized to fabricate HAp nanocomposites incorporating 1, 3 and 5 wt% each of GO, MWCNTs, GONRs and Ag NPs. Characterization using such techniques as XRD, FTIR, HRSEM and EDS was performed to analyze the physicochemical properties of nanocomposites, and MTT assay, hemolysis, bioactivity and drug release to evaluate the biological properties. The XRD and HRSEM results reveal that crystallite and particle size increase with increasing wt% of carbon nanomaterials and Ag NPs. However, the addition of nanomaterials did not modify the shape of HAp. The MTT assay and hemolysis results suggest GONRs possess better biocompatibility than GO and CNTs due to their smooth edge structure. While adding carbon materials up to 3 wt% caused an increase in the hardness, adding up to 5 wt% of them caused a decrease in the hardness due to the agglomeration of the particles. Biocompatibility and Vicker's hardness studies show that adding carbon nanomaterials up to 3 wt% caused significant improvement in biocompatibility and mechanical properties. Antibacterial activity test was performed to analyze the ability to preclude the formation of biofilms. The results showed better activity for silver-incorporated nanocomposites in the presence of E. coli and S. aureus bacteria. Drug release studies were performed using lidocaine drug and the results showed nearly similar drug release profile for all the samples except HAg3. Finally, nanocomposite HRA3 could be a suitable candidate for biomedical applications since it shows better biological and mechanical properties than GO and MWCNTs nanocomposites.


Assuntos
Durapatita , Nanocompostos , Antibacterianos/farmacologia , Carbono , Escherichia coli , Teste de Materiais , Prata/farmacologia , Staphylococcus aureus
6.
Mater Sci Eng C Mater Biol Appl ; 128: 112306, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34474857

RESUMO

Osteomyelitis is caused by Staphylococcus aureus (S. aureus), with associated progressive bone loss. This study developed for the first time a calcium phosphate cement (CPC) for delivery of doxycycline (DOX) and human platelet lysate (hPL) to fight against S. aureus infection and enhance the osteogenesis of human periodontal ligament stem cells (hPDLSCs). Chitosan-containing CPC scaffolds were fabricated in the absence (CPCC) or presence of DOX (CPCC+DOX). In addition, hPL was encapsulated in alginate microbeads and incorporated into CPCC+DOX (CPCC+DOX+ hPL). Flexural strength of CPCC+DOX + hPL was (5.56 ± 0.55) MPa, lower than (8.26 ± 1.6) MPa of CPCC+DOX (p < 0.05), but exceeding the reported strength of cancellous bone. CPCC+DOX and CPCC+DOX + hPL exhibited strong antibacterial activity against S. aureus, reducing biofilm CFU by 4 orders of magnitude. The hPDLSCs encapsulated in microbeads were co-cultured with the CPCs. The hPDLSCs were able to be released from the microbeads and showed a high proliferation rate, increasing by about 8 folds at 14 days for all groups. The hPL was released from the scaffold and promoted the osteogenic differentiation of hPDLSCs. ALP activity was 28.07 ± 5.15 mU/mg for CPCC+DOX + hPL, higher than 17.36 ± 2.37 mU/mg and 1.34 ± 0.37 mU/mg of CPCC+DOX and CPCC, respectively (p < 0.05). At 7 days, osteogenic genes (ALP, RUNX2, COL-1, and OPN) in CPCC+DOX + hPL were 3-10 folds those of control. The amount of hPDLSC-synthesized bone mineral with CPCC+DOX + hPL was 3.8 folds that of CPCC (p < 0.05). In summary, the novel CPC + DOX + hPL-hPDLSCs scaffold exhibited strong antibacterial activity, excellent cytocompatibility and hPDLSC osteogenic differentiation, showing a promising approach for treatment and prevention of bone infection and enhancement of bone regeneration.


Assuntos
Osteogênese , Ligamento Periodontal , Biofilmes , Fosfatos de Cálcio/farmacologia , Diferenciação Celular , Células Cultivadas , Humanos , Staphylococcus aureus , Células-Tronco
7.
Mater Sci Eng C Mater Biol Appl ; 128: 112320, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34474871

RESUMO

This study aimed to fabricate cinnamon essential oil (CO)-laden 45S5 bioactive glass (BG)/soy protein (SP) scaffolds exhibiting antioxidant and antibacterial activity. In this regard, 45S5 BG-based scaffolds were produced by the foam replica method, and subsequently the scaffolds were coated with various concentrations of CO (2.5, 5 and 7 (v/v) %) incorporated SP solution. Scanning electron microscopy images revealed that the CO-laden SP effectively attached to the 45S5 BG scaffold struts. The presence of 45S5 BG, SP and CO was confirmed using Fourier transform infrared spectroscopy. Compressive strength results indicated that SP based coatings improved the scaffolds' mechanical properties compared to uncoated BG scaffolds. The loading efficiency and releasing behaviour of the different CO concentrations were tested by gas chromatography-mass spectroscopy and UV-Vis spectroscopy. The results showed that CO incorporated scaffolds have controlled releasing behaviour over seven days. Furthermore, the coating on the scaffold surfaces slightly retarded, but it did not inhibit, the in vitro bioactivity of the scaffolds. Moreover, the antioxidant and antibacterial activity of CO was studied. The free radical scavenging activity measured by DPPH was 5 ± 1, 41 ± 3, 44 ± 1 and 43 ± 1 % for BGSP, CO2.5, CO5 and CO7, respectively. The antioxidant activity was thus enhanced by incorporating CO. Agar diffusion and colony counting results indicated that the incorporation of CO increased the antibacterial activity of scaffolds against S. aureus and E. coli. In addition, cytotoxicity of the scaffolds was investigated using MG-63 osteoblast-like cells. The results showed that the BG-SP scaffold was non-toxic under the investigated conditions, whereas dose-dependent toxicity was observed in CO-laden scaffolds. Considered together, the developed phytotherapeutic agent laden 45S5 BG-based scaffolds are promising for bone tissue engineering exhibiting capability to combat bone infections and to protect against oxidative stress damage.


Assuntos
Antioxidantes , Óleos Voláteis , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Cerâmica , Cinnamomum zeylanicum , Escherichia coli , Vidro , Óleos Voláteis/farmacologia , Estresse Oxidativo , Proteínas de Soja , Staphylococcus aureus , Engenharia Tecidual , Tecidos Suporte
8.
Ethiop J Health Sci ; 31(3): 635-644, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34483621

RESUMO

Background: Surgical wound infections (SWI) remain as a major source of postoperative illness that increases the time of hospital stay and health care related costs globally. On top of this, the emergence and spread of drug-resistant pathogens continue to challenge the proper management of surgical wound infections. Methods: A hospital based cross-sectional study was conducted at Felege Hiwot Referral Hospital (FHRH). A total of 165 study participants were included. Socio-demographic data were collected using a pre-tested structured questionnaire. Isolates were identified by conventional bacteriological technique and antimicrobial susceptibility test was performed using the Kirby-Bauer disc diffusion method. Results: Among 165 study participants, 98 (59.4%) were males. The overall prevalence of culture confirmed surgical wound infection was 115 (69.7%). A total of 125 bacteria isolates were identified among which, Staphylococcus aureus was predominant followed by Pseudomonas aeruginosa and Klebsiella species with a proportion of 31 (24.8%), 26 (20.8%) and 17 (13.6%), respectively. Majority (80.8%) of the isolates were found multidrug resistant (MDR). Dirty wound and duration of hospital stay were found significantly associated with culture confirmed surgical wound infections. Conclusions: S. aureus, P. aeruginosa and Klebsiella species were the most common isolates identified from surgical wound sites. Most of these pathogens were found MDR. Therefore, regular surveillance on the types of bacterial isolates and their drug resistance pattern should be considered.


Assuntos
Antibacterianos , Infecção da Ferida Cirúrgica , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Estudos Transversais , Farmacorresistência Bacteriana , Farmacorresistência Bacteriana Múltipla , Etiópia/epidemiologia , Hospitais , Humanos , Masculino , Testes de Sensibilidade Microbiana , Encaminhamento e Consulta , Staphylococcus aureus , Infecção da Ferida Cirúrgica/tratamento farmacológico , Infecção da Ferida Cirúrgica/epidemiologia
9.
Ethiop J Health Sci ; 31(3): 645-652, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34483622

RESUMO

Background: The emergence and spread of antimicrobial resistance (AMR) among uropathogens is increasing, especially in resource limited settings due to a number of reasons. The production of Extended Spectrum ß-Lactamase (ESBL) by some strains of E. coli and methicillin resistant Staphylococcus species, limits the choice of antimicrobials in the treatment of urinary tract infection (UTI) globally. However, little is known about the type of uropathogenes and their current AMR profile among pregnant women in Hargeisa, Somaliland. Methods: Clean-catch mid-stream urine samples were collected and processed for bacteriological culture and antimicrobial sensitivity testing (AST). Ceftazidime (30µg) and Cefotaxime (30µg) disks were used for ESBL screening as per CLSI guideline and each ESBL screening positive isolate were phenotypically confirmed by a combination disk test. Results: Among 376 study participants, 79 (21.0%) had significant bacteriuria (SBU). Majority at 58(73.4%) of the isolates were Gram-negative. The most predominant isolate was E.coli, 36(45.6%) followed by K. pneumonea 16(20.3%) and S. aureus at 9(11.4 %). The proportion of ESBL producing isolates was 25(32.9%). Gram-negatives showed high level resistance to ampicillin, amoxicillin, cefotaxime, and cephalexin at 87%, 85%, 57%, and 52%, respectively. Previous history of UTI, monthly income, educational status and having dysuria were significantly associated with SBU (p<0.05). Conclusion: Relatively high prevalence of uropathogens and an increased level of drug resistance were documented. Therefore, continued surveillance on the type of uropathogens and their AMR pattern is needed to ensure appropriate recommendations for the rational empirical treatment of UTI and for policy input.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Infecções Urinárias , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana , Escherichia coli , Feminino , Hospitais , Humanos , Testes de Sensibilidade Microbiana , Gravidez , Gestantes , Staphylococcus aureus , Infecções Urinárias/tratamento farmacológico , beta-Lactamases
10.
Nanoscale ; 13(29): 12546-12552, 2021 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-34477613

RESUMO

A metal-organic framework (MOF) material was prepared from 2-aminoterephthalic acid and aluminum chloride with a solvothermal synthesis protocol. The as-prepared MOF material named NH2-MIL-53(Al) emitted a very intensive fluorescent (FL) signal after it was hydrolyzed in alkaline solution for releasing numerous FL ligands NH2-H2BDC. Thus it can be considered as a sensitive FL probe for studying biorecognition events. In this proof-of-principle work, a double-site recognition method was established to quantify Staphylococcus aureus (S. aureus) relying on the alkaline hydrolysis property of the MOF material. In particular, magnetic beads (MBs) modified with pig IgG were adopted for binding S. aureus based on the strong affinity between pig IgG and protein A on the bacterial surface. Meanwhile, MOF NH2-MIL-53(Al)-tagged teicoplanin (TEI) was adopted for tracing the target bacteria. By hydrolyzing the MOF material bound on the MBs to trigger the FL signal, S. aureus can be quantified with a dynamic range of 3.3 × 103-3.3 × 107 CFU mL-1 and a detection limit of 5.3 × 102 CFU mL-1 (3σ). The method can exclude efficiently the interference from other common bacteria. It has been applied to quantify S. aureus in saliva, pomegranate green tea, glucose injection and milk samples with satisfactory results, verifying the application potential for analyzing various types of real samples contaminated with S. aureus.


Assuntos
Estruturas Metalorgânicas , Infecções Estafilocócicas , Animais , Corantes Fluorescentes , Hidrólise , Infecções Estafilocócicas/diagnóstico , Staphylococcus aureus , Suínos
11.
Nanoscale ; 13(31): 13506-13518, 2021 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-34477755

RESUMO

Photodynamic therapy (PDT) has evolved as an essential method for infection control, but is confronted with challenges in terms of low oxygen supply, possible toxicity during light irradiation, and nonpersistent action. Herein, to address these limitations, black phosphorus (BP) is used as a photosensitizer and decorated with Pt nanoparticles and aminobenzyl-2-pyridone (APy) moieties to obtain BP@APy-Pt. The stability of BP is improved through the capture and occupation of lone-pair electrons after reductive deposition of Pt nanoparticles and covalent conjugation of APy. Pt nanoparticles on BP@APy-Pt catalyze the decomposition of endogenous H2O2 to produce oxygen for consecutive cycles with a stable production capacity. The light exposure to BP@APy-Pt generates significantly higher 1O2 levels than those of BP/light, and the generated 1O2 is partially captured by APy moieties. The captured 1O2 during 20 min of illumination shows a constant release for 24 h in the dark. The cycled storage and release feature eliminates the toxicity of 1O2 at high levels during illumination and leads to efficient destruction of S. aureus and P. aeruginosa. Compared to the healing rates after treatment with BP/light (57.6%), BP@Pt/light (64.8%), BP@APy/light (77.8%), and BP@APy-Pt (48.5%), the skin wounds with infected S. aureus are fully healed after BP@APy-Pt/light treatment. Blood vessels and hair follicles are regenerated to resemble those of normal skin. Thus, this study expands the PDT strategy through integration with oxygen generation, 1O2 storage, and persistent release to promote bactericidal efficacy and eliminate side effects.


Assuntos
Oxigênio , Fotoquimioterapia , Homicídio , Peróxido de Hidrogênio , Fósforo , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Staphylococcus aureus
12.
Nanoscale ; 13(31): 13538-13549, 2021 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-34477758

RESUMO

The growing incidence of multidrug-resistant bacterial strains presents a major challenge in modern medicine. Antibiotic resistance is often exhibited by Staphylococcus aureus, which causes severe infections in human and animal hosts and leads to significant economic losses. Antimicrobial agents with enzymatic activity (enzybiotics) and phage therapy represent promising and effective alternatives to classic antibiotics. However, new tools are needed to study phage-bacteria interactions and bacterial lysis with high resolution and in real-time. Here, we introduce a method for studying the lysis of S. aureus at the single-cell level in real-time using atomic force microscopy (AFM) in liquid. We demonstrate the ability of the method to monitor the effect of the enzyme lysostaphin on S. aureus and the lytic action of the Podoviridae phage P68. AFM allowed the topographic and biomechanical properties of individual bacterial cells to be monitored at high resolution over the course of their lysis, under near-physiological conditions. Changes in the stiffness of S. aureus cells during lysis were studied by analyzing force-distance curves to determine Young's modulus. This allowed observing a progressive decline in cellular stiffness corresponding to the disintegration of the cell envelope. The AFM experiments were complemented by surface plasmon resonance (SPR) experiments that provided information on the kinetics of phage-bacterium binding and the subsequent lytic processes. This approach forms the foundation of an innovative framework for studying the lysis of individual bacteria that may facilitate the further development of phage therapy.


Assuntos
Bacteriófagos , Infecções Estafilocócicas , Animais , Humanos , Microscopia de Força Atômica , Staphylococcus aureus , Ressonância de Plasmônio de Superfície
13.
Braz J Biol ; 83: e247016, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34495153

RESUMO

Pheretima posthuma (Vaillant, 1868), a native earthworm of Pakistan and Southeast Asia, has wide utilization in vermicomposting and bioremediation process. In this study, P. posthuma coelomic fluid (PCF) and body paste (PBP) was evaluated as antibacterial agent against ampicillin (AMP) resistant five Gram positive and four Gram negative clinical isolates. The antibacterial effect of different doses (i.e. 25-100 µg/ml) of PCF and PBP along with AMP and azithromycin (AZM) (negative and positive controls, respectively) were observed through disc diffusion and micro-dilution methods. All nine clinical isolates were noticed as AMP resistant and AZM sensitive. Antibacterial effects of PCF and PBP were dose dependent and zone of inhibitions (ZI) against all clinical isolates were between 23.4 ± 0.92 to 0 ± 00 mm. The sensitivity profile of PCF and PBP against clinical isolates was noticed as 44.44 and 55.56%, respectively. Both PCF and PBP showed bacteriostatic (BTS) action against S. aureus, S. pyogenes, K. pneumonia, N. gonorrhoeae. Moreover, the cumulative BTS potential of PCF and PBP against all isolates was 66.67 and 55.56%, respectively. The MICs of PCF and PBP were ranged from 50-200 µg/ml against selected isolates. The bacterial growth curves indicated that PCF and PBP inhibited the growth of all isolates at their specific MIC concentrations. However, PBP has better antibacterial potential compared to PCF against selected isolates. Therefore, it is concluded that both PCF and PBP of P. posthuma possess antibacterial and BTS potential against ampicillin resistant clinical isolates. This organism might be considered as a second choice of antibacterial agents and can further be utilized in pharmaceutical industries for novel drug manufacturing by prospecting bioactive potential agents.


Assuntos
Oligoquetos , Staphylococcus aureus , Ampicilina/farmacologia , Animais , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana
14.
Braz J Biol ; 83: e245585, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34495157

RESUMO

Many soil microorganisms' i.e., bacteria and fungi produce secondary metabolites called antibiotics. These are used for the treatment of some of the bacterial, fungal and protozoal diseases of humans. There is a need for isolation of a broad spectrum of antibiotics from microorganisms due to the emergence of antibiotic resistance. In the present study two antibiotic producing bacteria Klebsiella pneumoniae and Bacillus cereus were isolated from pharmaceutical and poultry feed industry of Hattar, Haripur Pakistan. Total 10 waste samples were collected from different industries (Marble, Ghee, Soap, Mineral, Steel, Poultry Feed, Pharmaceutical, Qarshi, Cosmetic and Glass). Thirty-three bacterial strains were isolated from industrial wastes of these ten different industries. Fourteen out of thirty-three bacterial strains exhibited antimicrobial activities against at least one of the test microbes considered in this study including Escherchia coli, Staphylococcus aureus and Salmonella typhi. The bacteria were isolated by standard serial dilution spread plate technique. Morphological characterization of the isolates was done by Gram staining. Nine bacterial isolates out of fourteen were initially identified as B. cereus and five as K. pneumoniae through biochemical characterization. The antibacterial activities were tested by well diffusion method. Maximum number of antibiotic producing bacteria were isolated from pharmaceutical and poultry feed industry based on the results of primary screening, the most potential isolates S9, S19, S20, S22 and S23 were selected for secondary screening. The maximum activity against E. coli and S. aureus was recorded by bacterial isolate S19 i.e zones of inhibition of 6.5mm and 9mm while S20 showed 7.5mm and 6mm zones respectively. Molecular identification was carried out on the basis of 16S rRNA sequence analysis. Finally, the isolates were identified as B. cereus accession number LC538271and K. pneumoniae accession number MT078679. Analysis of bacterial extract S20 through GC-MS indicated the presence of 8 compounds of diverse nature and structure. Present study suggests that wastes of pharmaceutical and poultry feed industry may have antibiotic producing bacteria. These bacteria could be utilized for the production of antibiotics. B. cereus and K. pneumoniae isolated from wastes of poultry feed and pharmaceutical industries have the potential to produce antibiotics and could be used to control the microbial growth.


Assuntos
Resíduos Industriais , Staphylococcus aureus , Antibacterianos/farmacologia , Escherichia coli , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Testes de Sensibilidade Microbiana , Extratos Vegetais , RNA Ribossômico 16S
15.
Braz J Biol ; 83: e247701, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34468529

RESUMO

Staphylococcus aureus is an important foodborne pathogen associated to food intoxication and other multiple infections in human being. Its presence in salted food is a serious issue due to its salt tolerance potential. A study was conducted to analyze the presence of enterotoxins producing drug resistance S. aureus in salted sea fish from Gwadar. Freshly persevered samples (n=50) of salted fish were subjected to analyze the presence of S. aureus using 16S rRNA and Nuc genes primers. The isolates were then evaluated for drug resistance and enterotoxins producing potential using specific primers for MecA (methicillin resistance gene), (SEA) staphylococcal enterotoxin A and (SEB) staphylococcal enterotoxin B genes. Total 13/50 (26%) of the samples were found positive for the presence of S. aureus, preliminary confirmed with biochemical profiling and finally with the help of target genes presence. The isolates were found showing 100% resistant to methicillin, which were molecularly confirmed by the presence of MecA gene present in genome. The isolates 5/13 (38%) were positive for SEA and 3/13 (23%) for SEB genes, whereas 2/13 (15%) were confirmed having both SEA and SEB genes in its genome. It was also confirmed that all the isolates were capable to form biofilm over the glass surfaces. It was concluded that the study confirmed the presence of enterotoxigenic methicillin resistance Staphylococcus aurous (MRSA) in salted fish product, that poses gross food safety concern. Preventive and control measures are necessary to handle this serious food safety concern.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Animais , Produtos Pesqueiros , Humanos , Staphylococcus aureus Resistente à Meticilina/genética , RNA Ribossômico 16S , Staphylococcus aureus/genética
16.
Front Cell Infect Microbiol ; 11: 672355, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34368010

RESUMO

Chronic rhinosinusitis with nasal polyps (CRSwNP) is characterized by Th2-skewed inflammation and increased colonization by Staphylococcus aureus. CRSwNP can be distinguished as eosinophilic (ECRSwNP) and non-eosinophilic (NECRSwNP) by the infiltration of eosinophils. The local microbiota plays an important role in the persistent inflammation of CRSwNP. To evaluate the bacterial community composition on the distinct types of CRSwNP patients, we collected nasal swabs from 16 ECRSwNP patients, 18 NECRSwNP patients, and 39 healthy control subjects. The microbiome structure for all the samples were analyzed by high-throughput 16S rRNA gene sequencing. Concentration of S. aureus was determined using TaqMan quantitative polymerase chain reaction (qPCR) targeting the nuclease (nuc) gene. The result showed significant differences in the sinus microbiome among healthy control subjects and CRSwNP patients. Microbiota community diversity was significantly lower in NECRSwNP samples compared to that of healthy control subjects. Interestingly, the abundance of several pathogenic bacteria was diverse between ECRSwNP and NECRSwNP patients. Although Staphylococcus prevailed in all groups, the abundance of Staphylococcus was significantly higher in the healthy control group than the ECRSwNP group. More importantly, the abundance of S. aureus was much higher in NECRSwNP patients. This study highlights that microbiota composition may contribute to the different clinical types of CRSwNP, inspiring new therapeutic strategies to resolve this chronic inflammation process.


Assuntos
Microbiota , Pólipos Nasais , Rinite , Doença Crônica , Humanos , Pólipos Nasais/complicações , RNA Ribossômico 16S/genética , Staphylococcus aureus
17.
Front Cell Infect Microbiol ; 11: 634215, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34381737

RESUMO

Bloodstream infections (BSIs), the presence of microorganisms in blood, are potentially serious conditions that can quickly develop into sepsis and life-threatening situations. When assessing proper treatment, rapid diagnosis is the key; besides clinical judgement performed by attending physicians, supporting microbiological tests typically are performed, often requiring microbial isolation and culturing steps, which increases the time required for confirming positive cases of BSI. The additional waiting time forces physicians to prescribe broad-spectrum antibiotics and empirically based treatments, before determining the precise cause of the disease. Thus, alternative and more rapid cultivation-independent methods are needed to improve clinical diagnostics, supporting prompt and accurate treatment and reducing the development of antibiotic resistance. In this study, a culture-independent workflow for pathogen detection and identification in blood samples was developed, using peptide biomarkers and applying bottom-up proteomics analyses, i.e., so-called "proteotyping". To demonstrate the feasibility of detection of blood infectious pathogens, using proteotyping, Escherichia coli and Staphylococcus aureus were included in the study, as the most prominent bacterial causes of bacteremia and sepsis, as well as Candida albicans, one of the most prominent causes of fungemia. Model systems including spiked negative blood samples, as well as positive blood cultures, without further culturing steps, were investigated. Furthermore, an experiment designed to determine the incubation time needed for correct identification of the infectious pathogens in blood cultures was performed. The results for the spiked negative blood samples showed that proteotyping was 100- to 1,000-fold more sensitive, in comparison with the MALDI-TOF MS-based approach. Furthermore, in the analyses of ten positive blood cultures each of E. coli and S. aureus, both the MALDI-TOF MS-based and proteotyping approaches were successful in the identification of E. coli, although only proteotyping could identify S. aureus correctly in all samples. Compared with the MALDI-TOF MS-based approaches, shotgun proteotyping demonstrated higher sensitivity and accuracy, and required significantly shorter incubation time before detection and identification of the correct pathogen could be accomplished.


Assuntos
Bacteriemia , Infecções Estafilocócicas , Bacteriemia/diagnóstico , Candida albicans , Escherichia coli , Humanos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Infecções Estafilocócicas/diagnóstico , Staphylococcus aureus
18.
Cas Lek Cesk ; 160(4): 139-142, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34416816

RESUMO

Staphylococcus aureus (SAB) bacteremia is very serious and often fatal infection with the high incidence and lethality. Diagnosis of SAB must be followed by an appropriate diagnostic and therapeutic process. From the point of view of proper SAB management, it is essential to find the primary source of infection, which can be skin and soft tissue infections, catheter infections, infectious endocarditis, osteomyelitis, pneumonia or abscesses with hematogenous spread. After the SAB has been identified, it is crucial to determine the appropriate examination and treatment procedure in close collaboration with an infectious disease specialist, clinical microbiologist and clinical pharmacist.


Assuntos
Bacteriemia , Infecções Estafilocócicas , Bacteriemia/diagnóstico , Bacteriemia/tratamento farmacológico , Humanos , Incidência , Infecções Estafilocócicas/diagnóstico , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus
19.
J Environ Sci (China) ; 107: 171-183, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34412780

RESUMO

Dimethyl phthalate (DMP), used as a plasticizer in industrial products, exists widely in air, water and soil. Staphylococcus aureus is a typical model organism representing Gram-positive bacteria. The molecular mechanisms of DMP toxicology in S. aureus were researched by proteomic and transcriptomic analyses. The results showed that the cell wall, membrane and cell surface characteristics were damaged and the growth was inhibited in S. aureus by DMP. Oxidative stress was induced by DMP in S. aureus. The activities of succinic dehydrogenase (SDH) and ATPase were changed by DMP, which could impact energy metabolism. Based on proteomic and transcriptomic analyses, the oxidative phosphorylation pathway was enhanced and the glycolysis/gluconeogenesis and pentose phosphate pathways were inhibited in S. aureus exposed to DMP. The results of real-time reverse transcription quantitative PCR (RT-qPCR) further confirmed the results of the proteomic and transcriptomic analyses. Lactic acid, pyruvic acid and glucose were reduced by DMP in S. aureus, which suggested that DMP could inhibit energy metabolism. The results indicated that DMP damaged the cell wall and membrane, induced oxidative stress, and inhibited energy metabolism and activation in S. aureus.


Assuntos
Proteômica , Staphylococcus aureus , Metabolismo Energético , Estresse Oxidativo , Ácidos Ftálicos
20.
Int J Med Microbiol ; 311(6): 151524, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34371345

RESUMO

Methicillin-resistant Staphylococcus aureus (MRSA) can colonize dental patients and students, however, studies on the prevalence of MRSA and methicillin-susceptible S. aureus (MSSA) among dental health care workers (DHCW) including use of personal protective equipment (PPE) are scarce. We conducted an observational study (StaphDent study) to (I) determine the prevalence of MRSA and MSSA colonization in DHCW in the region of Mecklenburg Western-Pomerania, Germany, (II) resolve the S. aureus population structure to gain hints on possible transmission events between co-workers, and (III) clarify use of PPE. Nasal swabs were obtained from dentists (n = 149), dental assistants (n = 297) and other dental practice staff (n = 38). Clonal relatedness of MSSA isolates was investigated using spa typing and, in some cases, whole genome sequencing (WGS). PPE use was assessed by questionnaire. While 22.3% (108/485) of the participants were colonized with MSSA, MRSA was not detected. MSSA prevalence was not associated with size of dental practices, gender, age, or duration of employment. The identified 61 spa types grouped into 17 clonal complexes and four sequence types. Most spa types (n = 47) were identified only once. In ten dental practices one spa type occurred twice. WGS data analysis confirmed a close clonal relationship for 4/10 isolate pairs. PPE was regularly used by most dentists and assistants. To conclude, the failure to recover MRSA from DHCW reflects the low MRSA prevalence in this region. Widespread PPE use suggests adherence to routine hygiene protocols. Compared to other regional HCW MRSA rates the consequent usage of PPE seems to be protective.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Atenção à Saúde , Pessoal de Saúde , Humanos , Staphylococcus aureus Resistente à Meticilina/genética , Infecções Estafilocócicas/epidemiologia , Staphylococcus aureus/genética
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