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1.
Int J Food Microbiol ; 361: 109473, 2022 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-34768041

RESUMO

The epidemiological characteristics of Salmonella spp. in pork have been widely studied in China, but the results remain inconsistent. This study aimed to summarize the epidemiological characteristics of Salmonella spp. isolated from pork, including its prevalence, serovar distribution, and antibiotic resistance rate. We systematically reviewed published studies on Salmonella spp. isolated from pork in China between 2000 and 2020 in two Chinese and three English databases and quantitatively summarized its prevalence, serovar distribution, and antibiotic resistance using meta-analysis methods. Furthermore, we conducted subgroup analysis and meta-regression to explore the source of the heterogeneity from historical changes and regional difference perspectives. Ninety-one eligible studies published between 2000 and 2020 were included. The meta-analysis showed that the pooled prevalence of Salmonella isolated from pork was 0.17 (95% CI: 0.14, 0.20), with a detected growing trend over time. For the proportions of serovars, Derby (0.32, 95% CI: 0.26, 0.38), Typhimurium (0.10, 95% CI: 0.07, 0.15) and London (0.05, 95% CI: 0.03, 0.08) were dominant in these studies. The antibiotic resistance rates were high for tetracycline (0.68, 95% CI: 0.59, 0.77), sulfisoxazole (0.65, 95% CI: 0.45, 0.83), ampicillin (0.43, 95% CI: 0.34, 0.53), streptomycin (0.42, 95% CI: 0.29, 0.56), and sulfamethoxazole (0.42, 95% CI: 0.25, 0.60). The results of this study revealed a high prevalence, the regional characteristics of serovar distribution, and the severe challenges of antibiotic resistance of Salmonella originating from pork in China, suggesting the potential increasing risk and disease burden. Therefore, it is necessary to improve the prevention and control strategies of Salmonella in pork.


Assuntos
Carne de Porco , Carne Vermelha , Animais , China/epidemiologia , Resistência Microbiana a Medicamentos , Testes de Sensibilidade Microbiana , Prevalência , Salmonella , Sorogrupo , Suínos
2.
Chemosphere ; 287(Pt 4): 132276, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34601372

RESUMO

Phytoconstituents of plants had enormous therapeutic potential against the wounds on skin. Plants like Tecoma stans, Manilkara zapota and Cassia fistula were some which had the ability to heal the wounds. However, there was limited research in Cassia fistula flowers and its synergism with plants on wound healing and its mechanism. Qualitative analysis was performed to confirm the presence of phytoconstituents like flavonoids, saponins and tannins in solvents:aqueous ethanol and methanol. All three components showed their attributes towards wound healing. Results of antimicrobial activity clearly stated that, methanol extract of the Cassia fistula flowers at increasing concentration, showed the maximum zone of inhibition of 27 mm at 100 µl (antibacterial assay) and 18 mm at 100 µl (anti-fungal assay). They had higher potential against the selective microbes Staphylococcus aureus and Aspergillus niger. The combination of C. fistula flowers and C. fistula leaves; C. fistula flowers and M. zapota leaves showed maximum zone of inhibition of 23 mm and 21 mm for anti-bacterial; 22 mm and 23 mm for antifungal at 100 µl respectively. The C. fistula flowers along with the Manilkara zapota leaves and C. fistula leaves enhanced the antimicrobial nature than the individual plants. The antimicrobial properties present in the plants would engage them in future for developing an improved medicine for wound healing. Thus a polyherbal plant solution containing equal proportions of plants, tested for the antibacterial activity, succeeded by showing its higher inhibition of 25 mm at 100 µl.This concluded that the synergism of plants had higher efficiency in microbial activity than the individual samples hence proving the plants attributes towards the wound healing.


Assuntos
Anti-Infecciosos , Bignoniaceae , Plantas Medicinais , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Testes de Sensibilidade Microbiana , Extratos Vegetais/farmacologia , Folhas de Planta
3.
Chemosphere ; 287(Pt 2): 132131, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34492413

RESUMO

Ion exchange membranes (IEMs) are widely used in water treatment applications such as electrodialysis. However, the exploration of IEMs as effective antibacterial food contact materials (e.g., food packaging membranes) against pathogenic bacteria to ensure food safety has not been reported. Here, we report a simple but effective method to prepare high performance antibacterial membranes via ion exchange coupled with in-situ reduction. The general membrane properties are characterized using SEM, EDS, FTIR, XPS, XRD, DSC, TGA, water uptake, etc. The distribution of silver and copper in the membranes are generally in line with the distribution of sulfur, indicating that the antibacterial ions are introduced into the membranes via ion exchange and are bonded with the sulfonate groups in the membranes. The antibacterial performance is investigated using zone of inhibition tests and continuous bacteria growth inhibition tests. All of the prepared membranes show obvious antibacterial activities compared to the bare cation exchange membranes. The diameters of inhibition zone against Staphylococcus aureus (S. aureus) are all larger than those of Escherichia coli (E. coli), indicating that the prepared membranes are more efficient in inhibiting S. aureus compared to E. coli. Furthermore, the silver-based membrane shows more sustainable antibacterial activities compared to the copper-based membrane. Especially, the results clearly reveal that the silver-based membrane is capable of killing bacteria instead of just inhibiting the growth of bacteria. We have shown for the first time that membranes derived from IEMs have the potential as food contact materials to inhibit the growth of pathogenic bacteria so as to eliminate the risk of bacterial infections and meanwhile delay food spoilage due to bacteria growth.


Assuntos
Nanopartículas Metálicas , Prata , Antibacterianos/farmacologia , Cobre , Escherichia coli , Troca Iônica , Testes de Sensibilidade Microbiana , Prata/farmacologia , Staphylococcus aureus
4.
Chemosphere ; 287(Pt 3): 132271, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34547560

RESUMO

In this study, novel biogenic silver (AgNPs) and gold nanoparticles (AuNPs) were developed using a green approach with Ganoderma lucidum (GL) extract. The optimization of synthesis conditions for the best outcomes was conducted. The prepared materials were characterized and their applicability in catalysis, antibacterial and chemical sensing was comprehensively evaluated. The GL-AgNPs crystals were formed in a spherical shape with an average diameter of 50 nm, while GL-AuNPs exhibited multi-shaped structures with sizes ranging from 15 to 40 nm. As a catalyst, the synthesized nanoparticles showed excellent catalytic activity (>98% in 9 min) and reusability (>95% after five recycles) in converting 4-nitrophenol to 4-aminophenol. As an antimicrobial agent, GL-AuNPs were low effective in inhibiting the growth of bacteria, while GL-AgNPs expressed strong antibacterial activity against all the tested strains. The highest growth inhibition activity of GL-AgNPs was observed against B. subtilis (14.58 ± 0.35 mm), followed by B. cereus (13.8 ± 0.52 mm), P. aeruginosa (12.38 ± 0.64 mm), E. coli (11.3 ± 0.72 mm), and S. aureus (10.41 ± 0.31 mm). Besides, GL-AgNPs also demonstrated high selectivity and sensitivity in the colorimetric detection of Fe3+ in aqueous solution with a detection limit of 1.85 nM. Due to the suitable thickness of the protective organic layer and the appropriate particle size, GL-AgNPs validated the triple role as a high-performance catalyst, antimicrobial agent, and nanosensor for environmental monitoring and remediation.


Assuntos
Anti-Infecciosos , Nanopartículas Metálicas , Antibacterianos/farmacologia , Catálise , Colorimetria , Escherichia coli , Compostos Férricos , Ouro , Química Verde , Íons , Testes de Sensibilidade Microbiana , Extratos Vegetais , Prata , Staphylococcus aureus
5.
Food Chem ; 372: 131344, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34818747

RESUMO

Hylocereus costaricensis peel contains large amounts of betacyanins and can be exploited as a source of natural colorants. This work aimed the chemical characterization and evaluation of bioactive properties of this by-product and the optimization of the ultrasound-assisted extraction (UAE) of betacyanins using the response surface methodology (RSM). Oxalic and malic acids and traces of fumaric acid were detected, as well as the four tocopherol isoforms, predominantly γ-tocopherol. Four betacyanins were identified and used as response criteria for UAE optimization, namely phyllocactin, isobetanin, isophyllocactin, and betanin. Sample processing at 487 W for 38 min result in the maximum betacyanin content (36 ± 1 mg/g dw). The peel extract inhibit the oxidative haemolysis, with IC50 values of 255 and 381 µg/mL for Δt of 60 and 120 min, respectively, and the growth of pathogenic bacteria, with minimum inhibitory concentrations ranging from 5 to 20 mg/mL. Furthermore, no toxicity was observed for normal cells.


Assuntos
Cactaceae , Extratos Vegetais , Corantes , Testes de Sensibilidade Microbiana
6.
Sci Total Environ ; 804: 150000, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34517324

RESUMO

Klebsiella spp. are ubiquitous bacteria capable of colonizing humans and animals, and sometimes leading to severe infections in both. Due to their high adaptability against environmental/synthetic conditions as well as their potential in aquiring antimicrobial/metal/biocide resistance determinants, Klebsiella spp. are recognized as an emerging threat to public health, worldwide. Currently, scarce information on the impact of livestock for the spread of pathogenic Klebsiella spp. is available. Thus, the phenotypic and genotypic properties of extended-spectrum ß-lactamase-producing, and colistin-resistant Klebsiella strains (n = 185) from process- and wastewater of two poultry and pig slaughterhouses as well as their receiving municipal wastewater treatment plants (mWWTPs) were studied to determine the diversity of isolates that might be introduced into the food-production chain or that are released into the environment by surviving the wastewater treatment. Selectively-isolated Klebsiella spp. from slaughterhouses including effluents and receiving waterbodies of mWWTPs were assigned to various lineages, including high-risk clones involved in human outbreaks, and exhibited highly heterogeneous antibiotic-resistance patterns. While isolates originating from poultry slaughterhouses showed the highest rate of colistin resistance (32.4%, 23/71), carbapenem-resistant Klebsiella spp. were only detected in mWWTP samples (n = 76). The highest diversity of resistance genes (n = 77) was detected in Klebsiella spp. from mWWTPs, followed by isolates from pig (n = 56) and poultry slaughterhouses (n = 52). Interestingly, no carbapenemase-encoding genes were detected and mobile colistin resistance genes were only obeserved in isolates from poultry and pig slaughterhouses. Our study provides in-depth information into the clonality of livestock-associated Klebsiella spp. and their determinants involved in antimicrobial resistance and virulence development. On the basis of their pathogenic potential and clinical importance there is a potential risk of colonization and/or infection of wildlife, livestock and humans exposed to contaminated food and/or surface waters.


Assuntos
Colistina , Klebsiella , Matadouros , Animais , Antibacterianos , Testes de Sensibilidade Microbiana , Suínos , Águas Residuárias , beta-Lactamases
7.
J Infect Chemother ; 28(1): 1-5, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34580009

RESUMO

The Urogenital Sub-committee and the Surveillance Committee of the Japanese Society of Chemotherapy, The Japanese Association for Infectious Diseases, and the Japanese Society for Clinical Microbiology conducted the second nationwide surveillance of the antimicrobial susceptibility of Chlamydia trachomatis. In this second surveillance study, clinical urethral discharge specimens were collected from patients with urethritis in 26 hospitals and clinics from May 2016 to July 2017. Based on serial cultures, the minimum inhibitory concentration (MIC) could be determined for 41 isolates; the MICs (MIC90) of ciprofloxacin, levofloxacin, tosufloxacin, sitafloxacin, doxycycline, minocycline, erythromycin, clarithromycin, azithromycin and solithromycin were 2 µg/ml (2 µg/ml), 1 µg/ml (0.5 µg/ml), 0.25 µg/ml (0.25 µg/ml), 0.125 µg/ml (0.063 µg/ml), 0.125 µg/ml (0.125 µg/ml), 0.25 µg/ml (0.25 µg/ml), 0.031 µg/ml (0.031 µg/ml), 0.25 µg/ml (0.125 µg/ml), and 0.016 µg/ml (0.008 µg/ml), respectively. In summary, this surveillance project did not identify any strains resistant to fluoroquinolone, tetracycline, or macrolide agents in Japan. In addition, the MIC of solithromycin was favorable and lower than that of other antimicrobial agents. However, the MIC of azithromycin had a slightly higher value than that reported in the first surveillance report, though this might be within the acceptable margin of error. Therefore, the susceptibility of azithromycin, especially, should be monitored henceforth.


Assuntos
Chlamydia trachomatis , Uretrite , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Azitromicina/farmacologia , Farmacorresistência Bacteriana , Humanos , Japão/epidemiologia , Masculino , Testes de Sensibilidade Microbiana , Uretrite/tratamento farmacológico , Uretrite/epidemiologia
8.
J Infect Chemother ; 28(1): 29-34, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34674944

RESUMO

OBJECTIVES: As a newly emerging pathogen, Candida auris has spread rapidly and caused a serious invasive infection. Candida auris often appeared high resistance to classical antifungal drugs. Drug combination therapy is emerging as an effective and well-established strategy to relieve drug resistance problems. The objective of present work was to examine the activity of fluconazole in combination with chlorhexidine acetate against Candida auris isolates. METHODS: Antiplanktonic activity was studied using the EUCAST methodology and growth curve assay. Antibiofilm effectiveness was determined by the crystal violet method, checkerboard microdilution assay, scanning electron microscopy, and confocal laser scanning microscopy. RESULTS: The results indicated that the 80% minimal inhibitory concentrations for fluconazole alone against Candida auris were 2-32 mg/L and for chlorhexidine acetate were 2-8 mg/L. The combination of fluconazole with chlorhexidine acetate exhibited synergism with the growth curve assay. In addition, the checkerboard microdilution assay presented that fluconazole was strongly synergistic with chlorhexidine acetate (sFICI <0.1875) in inhibiting the growth of Candida auris biofilms. The scanning electron microscopy and confocal laser scanning microscopy further exhibited the alteration of morphology of the cells and architecture of the biofilms. CONCLUSION: The combination therapy of fluconazole and chlorhexidine acetate provides a new potential strategy for the treatment of clinical Candida auris infection.


Assuntos
Candida , Fluconazol , Antifúngicos/farmacologia , Biofilmes , Candidíase Invasiva , Clorexidina/farmacologia , Fluconazol/farmacologia , Testes de Sensibilidade Microbiana , Suspensões
9.
Food Chem ; 366: 130608, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34454799

RESUMO

Hydrochar of waste walnut shells (WSH) was synthesized in the eco-friendly subcritical water medium (SWM) and its potential to fight against Klebsiella pneumoniae (K. pneumoniae), Staphylococcus aureus (S. aureus), Candida albicans (C. albicans) and Candida parapsilosis (C. parapsilosis) was investigated. Minimum Inhibitory Concentration (MIC) values of the WSH were 3.01 g/mL, 2.06 g/mL, 1.95 g/mL, and 3.12 g/mL for K. pneumoniae, S. aureus, C. albicans and C. parapsilosis, respectively. Survival of the pathogens was investigated by 3 min surface disinfection test exposure to WSH. While the highest inhibition was seen for C. parapsilosis (96.67%) on paper surface with 0.3 g/mL of bovine serum albumin (BSA), the lowest inhibition was determined for C. albicans (6.44%) on the plastic glass surface with 3 g/mL of BSA. An increase in protein, DNA, and potassium ion (K+) leakage was observed after microorganisms were incubated with WSH. This study provided an experimental basis for the practical application of WSH as a natural sanitizer agent.


Assuntos
Anti-Infecciosos , Juglans , Anti-Infecciosos/farmacologia , Candida albicans , Testes de Sensibilidade Microbiana , Staphylococcus aureus
10.
Ann Lab Med ; 42(1): 36-46, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34374347

RESUMO

Background: The emergence of carbapenemase-producing Enterobacteriaceae (CPE) represents a major clinical problem. Recently, the occurrence of CPE has increased globally, but epidemiological patterns vary across region. We report the trends in the genotypic distribution and antimicrobial susceptibility of CPE isolated from rectal and clinical samples during a four-year period. Methods: Between January 2016 and December 2019, 1,254 nonduplicated CPE isolates were obtained from four university hospitals in Korea. Carbapenemase genotypes were determined by multiplex real-time PCR. Antimicrobial susceptibility was profiled using the Vitek 2 system (bioMérieux, Hazelwood, MO, USA) or MicroScan Walkaway-96 system (Siemens West Sacramento, CA, USA). The proportions of carbapenemase genotypes and nonsusceptibility were analyzed using Pearson's chi-square test. Results: Among the 1,254 CPE isolates, 486 (38.8%), 371 (29.6%), 357 (28.5%), 8 (0.6%), 8 (0.6%), and 24 (1.9%) were Klebsiella pneumoniae carbapenemase (KPC), oxacillinase (OXA)-48-like, New Delhi metallo-ß-lactamase (NDM), imipenemase (IMP), Verona integron-encoded metallo-ß-lactamase (VIM), and multiple producers, respectively. The predominant species was K. pneumoniae (72.6%), followed by Escherichia coli (6.5%). More than 90% of the isolates harboring KPC, NDM, and OXA-48-like were nonsusceptible to cephalosporins, aztreonam, and carbapenems. Conclusions: The impact of CPE is primarily due to KPC-, NDM-, and OXA-48-like-producing K. pneumoniae isolates. Isolates carrying these carbapenemase are mostly multidrug-resistant. Control strategies based on these genotypic distributions and antimicrobial susceptibilities of CPE isolates are required.


Assuntos
Anti-Infecciosos , Enterobacteriáceas Resistentes a Carbapenêmicos , Infecções por Enterobacteriaceae , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Infecções por Enterobacteriaceae/epidemiologia , Genótipo , Hospitais Universitários , Humanos , Klebsiella pneumoniae , Testes de Sensibilidade Microbiana , República da Coreia , beta-Lactamases/genética
11.
Food Chem ; 368: 130831, 2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-34403999

RESUMO

This research aimed to apply nanotechnology for nanoformulation of Laurus nobilis essential oil (EO) by ultrasonic emulsification method and characterization of nano-form: particle size, viscosity, polydispersity index, thermodynamic stability, and surface tension. The antimicrobial activity of laurel EO nanoemulsion (LEON) and laurel EO was also investigated against a panel of ten food-borne pathogens and fish spoilage bacteria. The GC-MS analysis of EO revealed that 1,8-Cineole was the main volatile compound. According to disc-diffusion results, LEON was more effective against Gram-positive pathogen bacteria of Staphylococcus aureus and Enterococcus faecalis than EO. Laurel oil demonstrated a higher inhibitory effect against fish spoilage bacteria (6.19 to 18.5 mm). The MICs values of LEON and laurel EO ranged from 6.25 to >25 mg/mL and from 1.56 to >25 mg/mL, respectively. Nanoemulsion and oil exhibited the best bactericidal activity against Pseudomonas luteola. Therefore, LEON can be developed as a natural antimicrobial agent in food industry.


Assuntos
Anti-Infecciosos , Óleos Voláteis , Anti-Infecciosos/farmacologia , Bactérias , Testes de Sensibilidade Microbiana , Óleos Voláteis/farmacologia , Pseudomonas , Sesquiterpenos
12.
J Infect Chemother ; 28(1): 87-90, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34535403

RESUMO

We describe a case of a 48 years old male with left sided endocarditis and septic emboli secondary to a Pseudomonas aeruginosa strain that developed resistance to other ß-lactam antibiotics during therapy resulting in prolonged bacteremia. Blood cultures sterilized within 1 day of initiating ceftolozane/tazobactam 3 g every 8 hours in combination with ciprofloxacin. Steady state free ceftolozane plasma Cmax and Cmin concentrations were calculated to be 122.2µg/mL and 24.3µg/mL, respectively. The multidrug-resistant strain harbored chromosomal ß-lactamases OXA-486 and PDC-3, mutations in ampD and dacB predicted to lead to ampC over-expression, and mutations in OprD predicted to decrease outer membrane permeability. Following completion of a 42 day course and aortic valve replacement, the patient was deemed clinically cured without recurrence of infection at follow up 2 years later. To our knowledge, this is the first reported case to measure ceftolozane concentrations during the treatment of endocarditis which supports dose optimization approaches of severe endovascular disease due to multidrug resistant pathogens.


Assuntos
Endocardite , Infecções por Pseudomonas , Antibacterianos/uso terapêutico , Cefalosporinas/uso terapêutico , Endocardite/tratamento farmacológico , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Ácido Penicilânico , Infecções por Pseudomonas/tratamento farmacológico , Pseudomonas aeruginosa/genética , Tazobactam/uso terapêutico
13.
Mem Inst Oswaldo Cruz ; 116: e210207, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34755820

RESUMO

BACKGROUND: Treatment of mycoses is often ineffective, usually prolonged, and has some side effects. These facts highlight the importance of discovering new molecules to treat fungal infections. OBJECTIVES: To search the Medicines for Malaria Venture COVID Box for drugs with antifungal activity. METHODS: Fourteen human pathogenic fungi were tested against the 160 drugs of this collection at 1.0 µM concentration. We evaluated the ability of the drugs to impair fungal growth, their fungicidal nature, and morphological changes caused to cells. FINDINGS: Thirty-four molecules (21.25%) presented antifungal activity. Seven are antifungal drugs and one is the agricultural fungicide cycloheximide. The other drugs with antifungal activity included antibiotics (n = 3), antimalarials (n = 4), antivirals (n = 2), antiparasitcs (n = 3), antitumor agents (n = 5), nervous system agents (n = 3), immunosuppressants (n = 3), antivomiting (n = 1), antiasthmatic (n = 1), and a genetic disorder agent (n = 1). Several of these drugs inhibited Histoplasma capsulatum and Paracoccidioides brasiliensis growth (15 and 20, respectively), while Fusarium solani was not affected by the drugs tested. Most drugs were fungistatic, but niclosamide presented fungicidal activity against the three dimorphic fungi tested. Cyclosporine affected morphology of Cryptococcus neoformans. MAIN CONCLUSIONS: These drugs represent new alternatives to the development of more accessible and effective therapies to treat human fungal infections.


Assuntos
COVID-19 , Cryptococcus neoformans , Malária , Preparações Farmacêuticas , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Reposicionamento de Medicamentos , Humanos , Malária/tratamento farmacológico , Testes de Sensibilidade Microbiana , SARS-CoV-2
14.
Nat Prod Res ; 35(22): 4643-4647, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34798693

RESUMO

Staphylococcus aureus is an opportunistic agent that can cause a variety of infections, both hospital and community-acquired. Epigallocatechin gallate (EGCG), a flavonoid present in the leaves of Camellia sinensis, has different biological activities, including antimicrobial potential. Here we evaluate the antibacterial and antibiofilm potential of EGCG in nine clinical strains of S. aureus with different genetic profile and antimicrobial susceptibilities. The minimum inhibitory concentrations (MIC) of EGCG ranged from 7.81 to 62.5 µg/mL, and bactericidal activity was observed at 4 times the MIC. Sub-inhibitory concentrations were able to inhibit biofilm production. Concentrations ≤62.5 µg/mL of EGCG were non-cytotoxic for murine macrophages. EGCG significantly reduced the mortality of infected Galleria mellonella larvae with the S. aureus, having shown relevant antibiofilm properties and efficacy in inhibiting the growth of different clinical isolates of S. aureus, thus being a promising substance for the treatment of infections caused by this agent.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Staphylococcus aureus , Animais , Antibacterianos/farmacologia , Biofilmes , Catequina/análogos & derivados , Resistência a Meticilina , Camundongos , Testes de Sensibilidade Microbiana
15.
Nanoscale ; 13(44): 18632-18646, 2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34734624

RESUMO

We report a one-pot facile synthesis of highly photoresponsive bovine serum albumin (BSA) templated bismuth-copper sulfide nanocomposites (BSA-BiZ/CuxS NCs, where BiZ represents in situ formed Bi2S3 and bismuth oxysulfides (BOS)). As-formed surface vacancies and BiZ/CuxS heterojunctions impart superior catalytic, photodynamic and photothermal properties. Upon near-infrared (NIR) irradiation, the BSA-BiZ/CuxS NCs exhibit broad-spectrum antibacterial activity, not only against standard multidrug-resistant (MDR) bacterial strains but also against clinically isolated MDR bacteria and their associated biofilms. The minimum inhibitory concentration of BSA-BiZ/CuxS NCs is 14-fold lower than that of BSA-CuxS NCs because their multiple heterojunctions and vacancies facilitated an amplified phototherapeutic response. As-prepared BSA-BiZ/CuxS NCs exhibited substantial biofilm inhibition (90%) and eradication (>75%) efficiency under NIR irradiation. Furthermore, MRSA-infected diabetic mice were immensely treated with BSA-BiZ/CuxS NCs coupled with NIR irradiation by destroying the mature biofilm on the wound site, which accelerated the wound healing process via collagen synthesis and epithelialization. We demonstrate that BSA-BiZ/CuxS NCs with superior antimicrobial activity and high biocompatibility hold great potential as an effective photosensitive agent for the treatment of biofilm-associated infections.


Assuntos
Diabetes Mellitus Experimental , Animais , Antibacterianos/farmacologia , Biofilmes , Catálise , Camundongos , Testes de Sensibilidade Microbiana
16.
Vet Dermatol ; 32(6): 664-e174, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34796563

RESUMO

BACKGROUND: Topical treatments can be beneficial for managing canine superficial pyoderma. A novel antiseptic agent, olanexidine gluconate, has become available recently for use in humans, and its efficacy for canine pyoderma as topical therapy is unknown. OBJECTIVE: The antimicrobial effect of olanexidine was evaluated using minimal inhibitory concentration (MIC) towards Staphylococcus pseudintermedius. Furthermore, its clinical efficacy in canine superficial pyoderma was assessed in a randomized, single-blinded study. ANIMALS: Twenty-eight client-owned dogs with atopic dermatitis and superficial pyoderma. METHODS AND MATERIALS: The MIC of olanexidine was determined for S. pseudintermedius isolates (n=73) by serial dilution of 96-well broth microdilution method. Regarding the clinical trial, all recruited dogs were randomized into two groups; one treated with 1.5% olanexidine spray once daily and the other with a 3% chlorhexidine shampoo once a week for 2 times, respectively. Clinical assessment was performed at days 0 and 14 according to the guidelines of the Japanese Society of Antimicrobials for Animals. RESULTS: The MIC values for methicillin-resistant S. pseudintermedius (MRSP) and methicillin-sensitive S. pseudintermedius (MSSP) were 0.23 µg/ml and 0.24 µg/ml (P =0.9), respectively. In clinical trial, olanexidine and chlorhexidine showed substantial improvement in clinical presentation compared to the baseline. CONCLUSIONS AND CLINICAL IMPORTANCE: Olanexidine showed comparable efficacy to chlorhexidine (P=0.73). Moreover, the MIC against S. pseudintermedius indicated high bactericidal activity, which was supported by the topical effectiveness of olanexidine.


Assuntos
Doenças do Cão , Pioderma , Animais , Antibacterianos/uso terapêutico , Biguanidas , Doenças do Cão/tratamento farmacológico , Cães , Glucuronatos , Testes de Sensibilidade Microbiana/veterinária , Pioderma/tratamento farmacológico , Pioderma/veterinária , Staphylococcus
17.
Chem Commun (Camb) ; 57(93): 12476-12479, 2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34734602

RESUMO

We identified small-molecule enhancers of cellular stress granules by observing molecular crowding of proteins and RNAs in a time-dependent manner. Hit molecules sensitized the IRF3-mediated antiviral mechanism in the presence of poly(I:C) and inhibited the replication of SARS-CoV-2 by inducing stress granule formation. Thus, modulating multimolecular crowding can be a promising strategy against SARS-CoV-2.


Assuntos
Antivirais/farmacologia , Benzopiranos/farmacologia , Grânulos Citoplasmáticos/efeitos dos fármacos , Pirazóis/farmacologia , SARS-CoV-2/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos , Animais , Antivirais/química , Benzopiranos/química , Linhagem Celular Tumoral , Chlorocebus aethiops , Grânulos Citoplasmáticos/metabolismo , Relação Dose-Resposta a Droga , Combinação de Medicamentos , Humanos , Fator Regulador 3 de Interferon/metabolismo , Lopinavir/farmacologia , Testes de Sensibilidade Microbiana , Estrutura Molecular , Poli I-C/farmacologia , Pirazóis/química , Relação Estrutura-Atividade , Células Vero
18.
Molecules ; 26(21)2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34771067

RESUMO

Gastrointestinal tract infection caused by Helicobacter pylori is a common virulent disease found worldwide, and the infection rate is much higher in developing countries than in developed ones. In the pathogenesis of H. pylori in the gastrointestinal tract, the secretion of the urease enzyme plays a major role. Therefore, inhibition of urease is a better approach against H. pylori infection. In the present study, a series of syn and anti isomers of N-substituted indole-3-carbaldehyde oxime derivatives was synthesized via Schiff base reaction of appropriate carbaldehyde derivatives with hydroxylamine hydrochloride. The in vitro urease inhibitory activities of those derivatives were evaluated against that of Macrotyloma uniflorum urease using the modified Berthelot reaction. Out of the tested compounds, compound 8 (IC50 = 0.0516 ± 0.0035 mM) and compound 9 (IC50 = 0.0345 ± 0.0008 mM) were identified as the derivatives with potent urease inhibitory activity with compared to thiourea (IC50 = 0.2387 ± 0.0048 mM). Additionally, in silico studies for all oxime compounds were performed to investigate the binding interactions with the active site of the urease enzyme compared to thiourea. Furthermore, the drug-likeness of the synthesized oxime compounds was also predicted.


Assuntos
Antibacterianos/farmacologia , Inibidores Enzimáticos/farmacologia , Helicobacter pylori/efeitos dos fármacos , Indóis/farmacologia , Oximas/farmacologia , Urease/antagonistas & inibidores , Antibacterianos/síntese química , Antibacterianos/química , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Helicobacter pylori/enzimologia , Indóis/síntese química , Indóis/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Oximas/síntese química , Oximas/química , Estereoisomerismo , Urease/metabolismo
19.
Pan Afr Med J ; 40: 58, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34795837

RESUMO

Introduction: Marsdenia macrantha is a crucial source of traditional medicine in Northern Namibia. Its roots are used to treat various health conditions ranging from mouth infections to urinary retention. Despite its medicinal application, there is no known knowledge of its therapeutic properties. Thus, we investigated the phytochemical content and antibacterial activity of M. macrantha. Methods: M. macrantha root extracts were obtained using three different solvents (distilled water, methanol and acetone) - in the soxhlet and maceration extraction methods. Total phytochemical (terpenoid, alkaloid and/or flavonoid) content was determined by spectrophotometry. Antibacterial activity against common foodborne pathogens (Staphylococcus aureus, Escherichia coli and Salmonella typhi) was determined by both well and disc diffusion method. Results: we detected the presence of all the tested phytochemicals. Methanol gave the highest percentage yield of extraction (mean: 13.95 ± standard deviation: 0.41%) followed by water (10.92 ± 0.11%) and acetone (6.85 ± 0.23%), F-ratio=326.71 and p<0.0003. The total content determined showed that M. macrantha root extract contained more flavonoids than alkaloids (mg of standard per grams of the dry material). Antibacterial analyses showed inhibitory activity against all the selected pathogens, with the highest inhibition zone against S. typhi (19.7 ± 0.3 mm) - for the acetone-prepared root extract. There were variations in minimum inhibitory concentrations of the extracts prepared by the different solvents. Conclusion: this is the first study demonstrating the presence of phytochemicals and antibacterial properties of M. macrantha roots. Further studies are needed to isolate and characterize the phytochemicals for antibacterial application.


Assuntos
Antibacterianos/farmacologia , Marsdenia/química , Extratos Vegetais/farmacologia , Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Antibacterianos/isolamento & purificação , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Escherichia coli/efeitos dos fármacos , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Testes de Sensibilidade Microbiana , Compostos Fitoquímicos/química , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Raízes de Plantas , Salmonella typhi/efeitos dos fármacos , Solventes/química , Staphylococcus aureus/efeitos dos fármacos , Terpenos/isolamento & purificação , Terpenos/farmacologia
20.
BMC Res Notes ; 14(1): 432, 2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34823574

RESUMO

OBJECTIVES: In streptococci, the type M resistance to macrolides is due to the mef(A)-msr(D) efflux transport system of the ATP-Binding cassette (ABC) superfamily, where it is proposed that mef(A) codes for the transmembrane channel and msr(D) for the two ATP-binding domains. Phage ϕ1207.3 of Streptococcus pyogenes, carrying the mef(A)-msr(D) gene pair, is able to transfer the macrolide efflux phenotype to Streptococcus pneumoniae. Deletion of mef(A) in pneumococcal ϕ1207.3-carrying strains did not affect erythromycin efflux. In order to identify candidate genes likely involved in complementation of mef(A) deletion, the Mef(A) amino acid sequence was used as probe for database searching. RESULTS: In silico analysis identified 3 putative candidates in the S. pneumoniae R6 genome, namely spr0971, spr1023 and spr1932. Isogenic deletion mutants of each candidate gene were constructed and used in erythromycin sensitivity assays to investigate their contribution to mef(A) complementation. Since no change in erythromycin sensitivity was observed compared to the parental strain, we produced double and triple mutants to assess the potential synergic activity of the selected genes. Also these mutants did not complement the mef(A) function.


Assuntos
Macrolídeos , Streptococcus pneumoniae , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Farmacorresistência Bacteriana/genética , Macrolídeos/farmacologia , Testes de Sensibilidade Microbiana , Streptococcus pneumoniae/genética
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