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1.
FP Essent ; 489: 11-15, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31995349

RESUMO

Patients with bacterial skin and soft tissue infections (SSTIs) commonly present to family physicians. Common uncomplicated bacterial SSTIs include impetigo, ecthyma, cellulitis, erysipelas, abscesses, furuncles, and carbuncles. Risk factors for SSTIs include older age and chronic medical conditions, such as diabetes and cardiopulmonary or renal disease, and immunocompromise. Staphylococci and streptococci are the most common pathogens. Uncomplicated impetigo and ecthyma can be managed with topical antibiotics. Oral antibiotics should be prescribed for patients with complicated impetigo and ecthyma and for patients with cellulitis. For patients with cellulitis and systemic signs of infection, systemic antibiotics are indicated but hospitalization or intravenous administration may not be required. Erysipelas can be managed with oral or intravenous penicillin. Purulent SSTIs by definition involve collections of pus and include abscesses, furuncles, and carbuncles. Larger abscesses are appropriate for incision and drainage. Patients with uncomplicated carbuncles or abscesses may not require antibiotics afterward. However, antibiotics are recommended for patients with systemic inflammatory response syndrome (SIRS), patients with carbuncles or abscesses who have not improved with initial antibiotic therapy, patients with impaired host defenses, and patients with SIRS and hypotension.


Assuntos
Queimaduras , Dermatopatias Bacterianas , Infecções dos Tecidos Moles , Idoso , Antibacterianos , Queimaduras/complicações , Queimaduras/microbiologia , Humanos , Pacientes Ambulatoriais , Fatores de Risco , Dermatopatias Bacterianas/tratamento farmacológico , Infecções dos Tecidos Moles/tratamento farmacológico
2.
FP Essent ; 489: 16-20, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31995350

RESUMO

Fungal and viral skin infections are common and typically are managed by family physicians. The fungal skin infections commonly seen in family practice include the various forms of tinea: tinea corporis, tinea gladiatorum, tinea cruris, tinea pedis, tinea capitis, and tinea unguium (eg, onychomycosis). Common viral skin infections include herpes simplex virus infection, herpes zoster, cutaneous and genital warts, and molluscum contagiosum. Many fungal and viral skin infections have a classic appearance but variations and atypical manifestations can make patients with these conditions difficult to diagnose definitively. Confirmatory testing often is not required. In complex cases with atypical features, microscopy, culture, or blood tests can help in making a diagnosis. For some infections, treatment may be initiated before confirmatory test results are received. Most fungal skin infections can be managed effectively with topical antifungals. Tinea capitis and onychomycosis should be managed with oral drugs. Oral antiviral drugs are used to manage most viral skin infections but dosages vary based on the condition and phase of the infectious process. Cutaneous warts typically are managed with salicylic acid and/or cryotherapy.


Assuntos
Queimaduras , Dermatomicoses , Dermatopatias Infecciosas , Tinha , Queimaduras/complicações , Queimaduras/microbiologia , Dermatomicoses/diagnóstico , Dermatomicoses/tratamento farmacológico , Dermatomicoses/etiologia , Humanos , Pacientes Ambulatoriais , Dermatopatias Infecciosas/diagnóstico , Dermatopatias Infecciosas/tratamento farmacológico , Dermatopatias Infecciosas/etiologia , Tinha dos Pés
3.
J Med Microbiol ; 68(12): 1740-1746, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31718745

RESUMO

Introduction. One of the most important resistant mechanisms in Gram-negative bacteria is extended spectrum ß-lactamases (ESBLs). Harbour-related genes on plasmids, increase the risk of resistance transmission among commonly reported hospital infections.Aim. This study was designed to explore the dissemination of Pseudomonas aeruginosa producing ESBLs on their plasmids recovered from the different wards of Amir-Al-Momenin burn center, Affiliated with Shiraz University of Medical Sciences.Methodology. Among 256 isolates, 88 (34.38 %) P. aeruginosa strains were isolated from burn hospitalized patients. Samples were processed for antibiotic resistance using the Kirby-Bauer method while MIC was performed for colistin. MIC was used by the microdilution broth method as recommended by Clinical and Laboratory Standards Institute guidelines. Related studied genes were evaluated on extracted plasmids by the PCR method.Results. According to the phenotypic and molecular steps, a total of 58 (65.91 %) and 74 (84.10 %) strains detected positive ESBLs, respectively. Based on antibiogram tests, a total of 63 (71.59 %) isolates were detected as multidrug resistant. All ESBL P. aeruginosa isolates showed identical antimicrobial susceptibility profiles. The genotypic prevalence of ESBLs for bla SHV, bla TEM, bla GES, bla OXA-10 and bla PSE genes was 47.73, 78.41, 5.58, 3.41, 4.55 %, respectively.Conclusion. All P. aeruginosa strains producing ESBLs had plasmids containing related genes. The data indicated a high prevalence of ESBL among P. aeruginosa isolates in the southwest of the Iran burn center and their enzyme types were diverse.


Assuntos
Queimaduras/microbiologia , Plasmídeos , Pseudomonas aeruginosa/genética , beta-Lactamases/genética , Farmacorresistência Bacteriana Múltipla , Humanos , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/enzimologia
4.
Zhonghua Shao Shang Za Zhi ; 35(11): 798-803, 2019 Nov 20.
Artigo em Chinês | MEDLINE | ID: mdl-31775468

RESUMO

Objective: To explore the resistance mechanism and gene type of carbapenems-resistant Klebsiella pneumoniae (CRKP) in burn care unit. Methods: A total of 27 CRKP strains were primarily isolated from 22 patients [20 males, 2 females, aged (42±16) years] admitted to burn care unit of Institute of Burn Research of the First Affiliated Hospital of Army Medical University (the Third Military Medical University, hereinafter referred to as our department) from January to December 2017. After identification of bacteria, the months of detection and distribution of sample source were analyzed. Drug resistance tests of 15 antibiotics were conducted. Polymerase chain reaction was used to detect the drug resistant genes. Pulsed-field gel electrophoresis (PFGE) and multi-locus sequence typing (MLST) were used to analyze the gene type of strains. Results: (1) During the whole year of 2017, CRKP strains were mostly detected in August (8 strains), September (6 strains), and October (5 strains), with no CRKP in January, March, June, November, and December. Five strains from bed units were detected in August (2 strains), September (1 strain), and October (2 strains). (2) Twenty-seven CRKP strains were derived from blood samples (40.7%, 11/27), wound exudate samples (18.5%, 5/27), deep vein catheter samples (11.1%, 3/27), sputum samples (7.4%, 2/27), urine samples (3.7%, 1/27), and bed unit samples (18.5%, 5/27). (3) The 27 CRKP strains were detected with drug-resistance rates of 100.0% to 7 antibiotics including cefoperazone/sulbactam, piperacillin/tazobactam, cefazolin, ceftriaxone, cefepime, ertapenem, and compound sulfamethoxazole, no drug-resistance to tigecycline, with drug-resistance rates higher than 81.0% to the rest 7 antibiotics. (4) Detection rates for resistance gene bla(CTX-M-10), bla(SHV), bla(TEM), bla(CTX-M-14), bla(ACT), and bla(KPC) were all above 92.5%. (5) According to PFGE, the 27 CRKP strains had 6 types (A, A(1), A(2), B, C, and D). Strains of type A were mainly detected in February, May, and September, with detection rate of 37.0% (10/27). Strains of type C were mainly detected in July, August, and October, with detection rate of 48.1% (13/27). Strains of types A(1), A(2), B, and D were scatteredly detected, with detection rate of 3.7% (1/27) respectively. According to MLST, the 27 CRKP strains had 6 STs. ST11 was the most frequent type, accounting for 74.1% (20/27), which was detected in August to October. The detection rate of ST395, ST2230, ST215, ST260, and STnew ranged from 3.7%(1/27) to 7.4%(2/27), and the strains were scatteredly detected. Conclusions: The main source of CRKP from burn care unit of our department was bloodstream. All the CRKP strains showed high drug-resistance rate and complicated resistance mechanism. There were small scale outbreaks caused by CRKP of type A, type C, and ST11, which should be paid more attention to in clinical treatment and infection control.


Assuntos
Queimaduras/microbiologia , Carbapenêmicos/farmacologia , Farmacorresistência Bacteriana , Infecções por Klebsiella/epidemiologia , Klebsiella pneumoniae/efeitos dos fármacos , Adulto , Antibacterianos/farmacologia , Unidades de Queimados , Feminino , Humanos , Klebsiella pneumoniae/classificação , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Tipagem de Sequências Multilocus , beta-Lactamases/genética
5.
Mol Immunol ; 116: 98-105, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31634816

RESUMO

Pseudomonas aeruginosa is a common nosocomial pathogen in burn patients, and rapidly acquires antibiotic resistance; thus, developing an effective therapeutic approach is the most promising strategy for combating infection. Type III secretion system (T3SS) translocates bacterial toxins into the cytosol of the targeted eukaryotic cells, which plays important roles in the virulence of P. aeruginosa infections in both acute pneumonia and burn wound models. The PcrV protein, a T3SS translocating protein, is required for T3SS function and is a well-validated target in animal models of immunoprophylactic strategies targeting P. aeruginosa. In the present study, we evaluated the protective efficacy of chicken egg yolk antibodies (IgY) raised against recombinant PcrV (r-PcrV) in both acute pneumonia and burn wound models. R-PcrV protein was generated by expressing the pcrV gene (cloned in pET-28a vector) in E. coli BL-21. Anti-PcrV IgY was obtained by immunization of hen. Anti-PcrV IgY induced greater protection in P. aeruginosamurine acute pneumonia and burn wound models than control IgY (C-IgY) and PBS groups. Anti-PcrV IgY improved opsonophagocytic killing and inhibition of bacterial invasion of host cells. Taken together, our data provide evidence that anti-PcrV IgY can be a promising therapeutic candidate for combating P. aeruginosa infections.


Assuntos
Anticorpos Antibacterianos/imunologia , Antígenos de Bactérias/imunologia , Toxinas Bacterianas/imunologia , Queimaduras/imunologia , Imunoglobulinas/imunologia , Pneumonia/imunologia , Proteínas Citotóxicas Formadoras de Poros/imunologia , Infecções por Pseudomonas/imunologia , Pseudomonas aeruginosa/imunologia , Animais , Queimaduras/microbiologia , Galinhas/imunologia , Galinhas/microbiologia , Modelos Animais de Doenças , Feminino , Imunização/métodos , Camundongos , Camundongos Endogâmicos BALB C , Pneumonia/microbiologia , Vacinação/métodos , Virulência/imunologia
6.
Int J Nanomedicine ; 14: 5323-5338, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31409990

RESUMO

Background: Candida albicans as an opportunistic fungus is one of the most important causes of late-onset morbidity and mortality in patients with major burns and severely impaired immune system. In recent years, the emergence of resistance to opportunistic fungi and toxicity of antimicrobial drugs make it necessary to develop new drugs. Methods: In the present study, we investigated anticandidal effects of indolicidin, as a representative of host defense peptide, conjugated with gold nanoparticles in fluconazole-resistant clinical isolates of C. albicans. After characterizing the conjugation of indolicidin using biophysical methodologies, the cytotoxicity and hemolytic activity of the nanocomplex were examined. In addition, the expression level of ERG11, responsible for antifungal resistance, and the immunomodulatory effect of peptide-nanomaterial conjugates were assessed. Results: Our data indicated that the nanocomplex was nontoxic for the fibroblast cells and erythrocytes. Treatment with the nanocomplex significantly reduced the expression levels of the ERG11 gene in fluconazole-resistant C. albicans isolates and the iNOS gene in macrophages. Conclusion: The study data provides a chance to develop innovative therapies for the treatment of C. albicans burn infections. However, further investigation is required to examine the efficiency of the nanocomplex.


Assuntos
Antifúngicos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Queimaduras/microbiologia , Candida albicans/efeitos dos fármacos , Candida albicans/isolamento & purificação , Fluconazol/farmacologia , Ouro/farmacologia , Nanopartículas Metálicas/química , Animais , Peptídeos Catiônicos Antimicrobianos/química , Queimaduras/tratamento farmacológico , Candida albicans/genética , Morte Celular/efeitos dos fármacos , Farmacorresistência Fúngica/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Fluconazol/química , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Genes Fúngicos , Hemólise/efeitos dos fármacos , Humanos , Nanopartículas Metálicas/ultraestrutura , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , Células NIH 3T3 , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo
7.
Zhonghua Shao Shang Za Zhi ; 35(6): 456-458, 2019 Jun 20.
Artigo em Chinês | MEDLINE | ID: mdl-31280540

RESUMO

Objective: To analyze the prevalence trend of Klebsiella pneumoniae (KP) infection in the Department of Burns of the Second Affiliated Hospital of Zhejiang University School of Medicine (hereinafter referred to as the author's department) from 2015 to 2017, and to screen out the independent risk factors for sepsis in burn patients with KP infection. Methods: The clinical and bacteriological data of burn patients with KP infection from January 1, 2015 to December 31, 2017 were collected from the author's department. The variation trend in infection rates of KP and carbapenems-resistant KP (CRKP) during the three years were statistically analyzed, and the data were processed with chi-square test. Clinical data were processed with binary logistic regression analysis to screen out the independent risk factors for sepsis in burn patients with KP infection. Results: (1) From 2015 to 2017, 91 patients (50 males and 41 females, aged 15-90 years) with KP infection were diagnosed in the author's department, of which 65 cases were CRKP positive, and 26 cases were carbapenems-sensitive KP positive. The KP infection rates of patients in 2015, 2016, and 2017 were 5.79% (35/605), 4.08% (23/564), and 5.54% (33/596), respectively. The CRKP infection rates of patients in 2015, 2016, and 2017 were 3.31% (20/605), 3.37% (19/564), and 4.36% (26/596), respectively. There were no statistically significant differences in KP infection rate and CRKP infection rate of patients among the three years (χ(2)=2.007, 1.175, P>0.05). (2) Total burn area and CRKP infection were independent risk factors for sepsis in burn patients with KP infection (odds ratios=1.03, 5.88, 95% confidence intervals=1.01-1.05, 1.08-31.94, P<0.05). Conclusions: From 2015 to 2017, the infection rates of KP and CRKP in the author's department did not increase obviously, but the proportion of CRKP infection was high. CRKP infection is one of the independent risk factors for sepsis in burn patients with KP infection. Strengthening the prevention and treatment of CRKP infection may have certain value in decreasing the incidence of burn sepsis.


Assuntos
Queimaduras/complicações , Infecções por Klebsiella/epidemiologia , Klebsiella pneumoniae/isolamento & purificação , Sepse/complicações , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Queimaduras/microbiologia , China/epidemiologia , Feminino , Humanos , Infecções por Klebsiella/diagnóstico , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Sepse/epidemiologia , Adulto Jovem
8.
ACS Appl Mater Interfaces ; 11(22): 19743-19750, 2019 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-31081327

RESUMO

Injectable hydrogels are increasingly being used as scaffolds for in situ tissue engineering and wound healing. Most of these injectable hydrogels are made from polymers, and there are fewer examples of such soft materials made via self-assembly of low-molecular weight gelators. We report the room-temperature synthesis of a functional hydrogel formed by mixing cytidine (C) with 0.5 equiv each of B(OH)3 and AgNO3. The structural basis for this supramolecular hydrogel (C-B-C·Ag+) involves orthogonal formation of cytidine borate diesters (C-B-C) and Ag+-stabilized C-C base pairs, namely, the C·Ag+·C dimer. The C-B-C·Ag+ hydrogels, which can have high water content (at least 99.6%), are stable (no degradation after 1 year in the light), stimuli-responsive, and self-supporting, with elastic moduli of up to 104 Pa. Incorporation of Ag+ ions into the gel matrix endows the C-B-C·Ag+ hydrogel with significant antibacterial capability. Importantly, the rapid switching between the sol and gel states for this supramolecular hydrogel, as a response to shear stress, enables 3D printing of a flexible medical patch made from the C-B-C·Ag+ hydrogel. The C-B-C·Ag+ hydrogel was used to promote the closure of burn wounds in a mouse model.


Assuntos
Queimaduras/terapia , Hidrogéis/química , Nucleosídeos/química , Animais , Antibacterianos/uso terapêutico , Queimaduras/microbiologia , Escherichia coli/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Camundongos , Microscopia de Força Atômica , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Engenharia Tecidual/métodos , Cicatrização/efeitos dos fármacos , Cicatrização/fisiologia
9.
Chin Med J (Engl) ; 132(10): 1179-1187, 2019 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-31140989

RESUMO

BACKGROUND: Antibiotics are frequently used to treat critically ill patients, and its use is often accompanied by intestinal dysbiosis that might further lead to bacterial translocation (BT). Nevertheless, studies on the relationship between antibiotic therapy and BT are rare. In the present study, we investigated the effect of broad-spectrum antibiotics on BT in an experimental rat model of burn or sepsis injury. METHODS: The septic rat model was simulated by a second insult with lipopolysaccharides after burn injury. Ninety-two male Sprague-Dawley rats were randomly divided into control, burn, and sepsis groups (n = 8 or 9, each group), and the latter two groups were then treated with imipenem or ceftriaxone for 3 or 9 days. The mesenteric lymph nodes, liver, lungs, and blood were collected at each time point under sterile conditions for quantitative bacterial culture and strain identification. The differences between the groups were compared by Fisher exact test or Mann-Whitney U test. RESULTS: Only minimal Escherichia coli translocation to the mesenteric lymph nodes was observed in the normal control group, in which the BT rate was 12.5%. Burn injury did not affect the BT rate (Burn group vs. Control group, 12.5% vs. 12.5%, P = 1.000), whereas the BT rate showed an increased trend after the second insult with lipopolysaccharide (Sepsis group vs. Control group, 44.4% vs. 12.5%, P = 0.294), and many strains of Enterobacteria spp. were detected in distant organs (liver, lung, and blood) [Sepsis group vs. Control group, 0 (0,3) vs. 0 (0,0), U = 20, P = 0.045]. After the antibiotic treatment, BT to the distant organs was increased in burned rats [Burn IT3 group vs. Burn group, 0 (0,2) vs. 0 (0,0); Burn IT9 group vs. Burn group, 0 (0,1) vs. 0 (0,0); Burn CT9 group vs. Burn group, 0 (0,2) vs. 0 (0,0); all U = 20 and P = 0.076] but decreased in septic rats [Sepsis CT3 group vs. Sepsis group, 0 (0,0) vs. 0 (0,3), U = 20, P = 0.045]. The total amount of translocated bacteria, regardless of which antibiotic was used, was increased in burned rats [Burn IT9 group vs. Burn group, 2.389 (0,2.845) vs. 0 (0,2.301) Log10 colony-forming units (CFU)/g, U = 14, P = 0.034; Burn CT3 group vs. Burn group, 2.602 (0,3.633) vs. 0 (0,2.301) Log10 CFU/g, U = 10.5, P = 0.009], but there was a slightly decreased trend in septic rats [Sepsis IT9 group vs. Sepsis group, 2.301 (2,3.146) vs. 0 (0,4.185) Log10 CFU/g, U = 36, P = 0.721; Sepsis CT9 group vs. Sepsis group, 2 (0,3.279) vs. 0 (0,4.185) Log10 CFU/g, U = 32.5, P = 0.760]. Remarkably, the quantity of Enterococci spp. dramatically increased after broad-spectrum antibiotic treatment in both the burned and septic groups [Burn IT3 group vs. Burn group, 1 (0,5.164) vs. 0 (0,0) Log10 CFU/g, U = 16; Burn IT9 group vs. Burn group, 1 (0,2.845) vs. 0 (0,0) Log10 CFU/g, U = 16; Burn CT3 group vs. Burn group, 2.602 (0,3.633) vs. 0 (0,0) Log10 CFU/g, U = 8; Burn CT9 group vs. Burn group, 1 (0,4.326) vs. 0 (0,0) Log10 CFU/g, U = 16; Sepsis IT3 group vs. Sepsis group, 2.477 (0,2.903) vs. 0 (0,0) Log10 CFU/g, U = 4.5; Sepsis IT9 group vs. Sepsis group, 2 (0,3.146) vs. 0 (0,0) Log10 CFU/g, U = 9; Sepsis CT3 group vs. Sepsis group, 1.151 (0,2.477) vs. 0 (0,0) Log10 CFU/g, U = 18; Sepsis CT9 group vs. Sepsis group, 2 (0,3) vs. 0 (0,0) Log10 CFU/g, U = 13.5; all P < 0.05]. CONCLUSIONS: Broad-spectrum antibiotics promote BT in burned rats but prevent BT in septic rats, especially preventing BT to distant organs, such as the liver and lung. Moreover, Enterococci spp. with high drug resistance and high pathogenicity translocated most after antibiotic treatment.


Assuntos
Antibacterianos/uso terapêutico , Translocação Bacteriana/efeitos dos fármacos , Queimaduras/tratamento farmacológico , Queimaduras/microbiologia , Sepse/tratamento farmacológico , Sepse/microbiologia , Animais , Escherichia coli/efeitos dos fármacos , Escherichia coli/patogenicidade , Fígado/microbiologia , Pulmão/microbiologia , Linfonodos/microbiologia , Masculino , Ratos , Ratos Sprague-Dawley
11.
J Chemother ; 31(3): 120-126, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30849001

RESUMO

Pseudomonas aeruginosa is one of the most important causes of nosocomial infections, and its eradication is very difficult due to its multidrug resistance. The objective of the present study was to characterize the metallo-beta-lactamases (MBLs), integrons, OprD modifications and virulence factors of P. aeruginosa strains isolated from burn patients and to analyze their genetic relatedness by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). Sixty-seven P. aeruginosa isolates were recovered from different clinical samples of burn patients hospitalized in the Intensive Care Burn Unit of the Centre de Traumatologie et des Grands Brulés (Ben Arous, Tunisia), and MBLs and alterations in porin OprD were analyzed among imipenem-resistant isolates. Class 1 and 2 integrons were studied by PCR and sequencing of corresponding variable regions. The presence of eight genes involved in the virulence of P. aeruginosa was investigated by PCR. Fourteen of the 36 imipenem-resistant P. aeruginosa (IRPA) isolates (38.8%) were MBLs producers and harbored the blaVIM-2 gene, in all cases included into class 1 integrons. A new class 1 integron was identified (intI1-blaOXA-10-aadB-blaVIM-2-aadB-blaOXA-10). Five sequence types were detected among IRPA isolates: ST1, ST112, ST238, ST308 and ST395. P. aeruginosa is a major nosocomial pathogen in patients suffering burns, and the spreading of multidrugs resistant and MBL-producing isolates should be controlled in burn units. Moreover, the implantation of infection control guidelines is crucial to decrease the morbidity and mortality of nosocomial infections due to multidrug resistant P. aeruginosa.


Assuntos
Queimaduras/microbiologia , Imipenem/farmacologia , Integrons/genética , Infecções por Pseudomonas/epidemiologia , Pseudomonas aeruginosa/patogenicidade , Resistência beta-Lactâmica , beta-Lactamases/metabolismo , Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla , Hospitais , Humanos , Prevalência , Infecções por Pseudomonas/tratamento farmacológico , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/genética , Tunísia/epidemiologia , Fatores de Virulência/genética , Fatores de Virulência/metabolismo , beta-Lactamases/genética
12.
Colloids Surf B Biointerfaces ; 178: 488-499, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30925372

RESUMO

Usnic acid (UA) is a lichenic secondary metabolite useful for the treatment of burn wounds thanks to its antimicrobial activity, particularly toward strains responsible for their infections. However, the poor solubility is the main factor limiting the activity and thus its use in health care products. Adhesive polymeric films were designed to improve UA use by enhancing its bioavailability in the wounded tissues. Three different NaCMC hydrogel films, NaCMC 2% alone (F1), mixed to PVP K90 0.1% (F2) or to Carbopol 971 P 0.1% (F3), were prepared by casting method. Ex vivo experiments performed on pig skin samples showed their suitable adhesion capacity. in vitro release test, performed using the extraction cell, showed that film F2 provides the highest UA concentrations. Differential scanning calorimetry and X-ray analyses performed on the three films highlighted that UA is present in a more soluble form in F2. The in vitro antibacterial activity studies demonstrated that F2 is the most effective film against UA sensitive bacteria S. Epidermidis, E. Faecalis, B. Cereus and S. Pyogenes. In vitro cytotoxicity assays on human keratinocytes and fibroblasts showed that cells viability is not compromised.


Assuntos
Benzofuranos/química , Benzofuranos/farmacologia , Queimaduras/tratamento farmacológico , Queimaduras/microbiologia , Polímeros/química , Polímeros/farmacologia , Animais , Antibacterianos/efeitos adversos , Antibacterianos/química , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bacillus cereus/efeitos dos fármacos , Benzofuranos/efeitos adversos , Benzofuranos/uso terapêutico , Sobrevivência Celular/efeitos dos fármacos , Enterococcus faecalis/efeitos dos fármacos , Humanos , Queratinócitos/citologia , Queratinócitos/efeitos dos fármacos , Polímeros/efeitos adversos , Polímeros/uso terapêutico , Staphylococcus epidermidis/efeitos dos fármacos , Streptococcus pyogenes/efeitos dos fármacos , Suínos , Cicatrização/efeitos dos fármacos
13.
Pak J Pharm Sci ; 32(1(Supplementary)): 247-254, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30829200

RESUMO

Microbial infection is the most common and serious complication of burn injury, which is a major cause of morbidity and mortality. The aim of this study was to determine the bacteriological profiles and the antibiotic sensitivity patterns in burn unit of Allied Hospital Faisalabad over a period of 1 year. During the study period, 393 samples were collected and cultured by conventional method. Disk diffusion method was used to determine the sensitivity/resistance pattern of the isolates. Results were analyzed using SPPS version 20. Out of 393, 332 (84.5%) cases were found to be culture positive. Microbial contamination of the burn wounds was significantly (p<0.05) higher in males (89.3%) as compared to females (78.1%), and in 3rd degree burns (92.2%) as compared to 2nd degree burns (80.8%). Out of 393 patients, 258 (65.6%) cases were of Staphylococcus aurous followed by 169 (43.0%) of Pseudomonas aeruginosa 79 (20.1%) of Klebsiella pneumoniae and 67 (17.0%) of Escherichia coli. Among 258 cases of S. aurous, 153 (59.3%) were MRSA and 105 (40.7%) were MSSA. A large proportion (92.8%) of MRSA was sensitive to techoplanin and exhibited high-level resistant (96.7%) to fusidic acid whereas, significant proportion (74.4%) of MSSA isolates showed resistant to fusidic acid. A zero resistance was noted in coagulase negative staphylococci to linezolide, vancomycin and teichoplanin.. Pseudomonas aeruginosa exhibited high level resistance to tobramycin (91.7%) and were mostly sensitive (93.5%) to cefipiem. Klebsiella penumoniae was most sensitive to meropenem (100%) and most resistant to tobramycin (63.3%). E. coli showed zero resistance cefipiem and a small proportion of isolates (14.9%) exhibited resistance to tobramycin. In conclusion, S. aurous and P. aeruginosa represented the most common bacterial microbes of burn wounds which exhibited variable antibiotic susceptibility pattern. This study revealed a high potential for multiple microorganism outbreaks and emergence of resistant pathogens in burn patients due to the lack of patient screening and extended empirical use of antibiotics.


Assuntos
Antibacterianos/farmacologia , Queimaduras/microbiologia , Infecção dos Ferimentos/microbiologia , Adolescente , Adulto , Idoso , Unidades de Queimados/estatística & dados numéricos , Estudos Transversais , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Feminino , Humanos , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/isolamento & purificação , Masculino , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Paquistão/epidemiologia , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/isolamento & purificação , Infecção dos Ferimentos/tratamento farmacológico , Infecção dos Ferimentos/epidemiologia
14.
Mol Med Rep ; 19(5): 4057-4066, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30896813

RESUMO

Burn­site infections, commonly due to Pseudomonas aeruginosa, have been associated with deranged intestinal integrity, allowing bacteria and their products to translocate from the gut to the circulatory system. The P. aeruginosa quorum sensing (QS) transcription factor MvfR (PqsR) controls the expression of numerous virulence factors, and the synthesis of several toxic products. However, the role of QS in intestinal integrity alterations, to the best of our knowledge, has not been previously investigated. Using a proven anti­MvfR, anti­virulence agent, the in vivo results of the present study revealed that inhibition of MvfR function significantly decreased Fluorescein Isothiocyanate­Dextran (FITC­Dextran) flow from the intestine to the systemic circulation, diminished bacterial translocation from the intestine to mesenteric lymph nodes (MLNs), and improved tight junction integrity in thermally injured and infected mice. In addition, the MvfR antagonist administration alleviates the intestinal inflammation, as demonstrated by reduced ileal TNF­α and fecal lipocalin­2 concentrations. In addition, it is associated with lower levels of circulating endotoxin and decreased P. aeruginosa dissemination from the burn wound to the ileum. Collectively, these results hold great promise that the inhibition of this QS system mitigates gut hyperpermeability by attenuating the derangement of morphological and immune aspects of the intestinal barrier, suggesting that MvfR function is crucial in the deterioration of intestinal integrity following P. aeruginosa burn­site infection. Therefore, an anti­virulence approach targeting MvfR, could potentially offer a novel therapeutic approach against multi­drug resistant P. aeruginosa infections following thermal injuries. Since this approach is targeting virulence pathways that are non­essential for growth or viability, our strategy is hypothesized to minimize the development of bacterial resistance, and preserve the beneficial enteric microbes, while improving intestinal integrity that is deranged as a result of burn and infection.


Assuntos
Pseudomonas aeruginosa/patogenicidade , Percepção de Quorum , Animais , Antibacterianos/farmacologia , Proteínas de Bactérias/antagonistas & inibidores , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Queimaduras/microbiologia , Queimaduras/patologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Endotoxinas/sangue , Mucosa Intestinal/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Infecções por Pseudomonas/patologia , Percepção de Quorum/efeitos dos fármacos , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Fator de Necrose Tumoral alfa/sangue , Virulência
15.
Handchir Mikrochir Plast Chir ; 51(2): 130-138, 2019 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-30754065

RESUMO

BACKGROUND: Partial and full thickness burns require surgical treatment, such as early débridement and skin transplantation in MEEK/MESH technique or further reconstructive surgery. Infections of burns or transplanted areas limit surgical success and increase patient mortality. For split-thickness grafts in MEEK technique a superficial silk is applied as a protective on-top dressing, whereas in MESH technique fatty gauze and foam are used as standard protective covers over five to seven days. However, wound occlusion by both materials provides the soil for growth of microorganisms. The timely identification of impending infections is necessary to initiate early removal in order to safe and preserve skin grafts. Early identification of infections and removal of foreign material should therefore be attempted. MATERIAL AND METHODS: Burn wounds treated with split-thickness skin grafts processed by MEEK/MESH technique and covered with silk or foam overlayers were analyzed for signs of bacterial infection using the MolecuLight i:X™ device. In addition, swaps for microbiological analysis where taken from fluorescent areas and correlated with florescent image results. RESULTS: We examined burn wounds (n = 14) of three different intensive care patients. The MolecuLight i:X™ camera showed a strong colonization of the transplanted areas and foreign materials, that were in line with microbiological analysis findings. The representation of the excitation load showed high values in the foreign materials. The take rate of MEEK-transplants was 90 % compared to MESH-transplanted with about 60 %. The positive predictive value was 81.8 % for detection of a wound infection with autofluorescence. The negative predictive value was 90.3 % with a sensitivity of 86.7 % and a specificity of 87.5 %. CONCLUSION: The representation of the fluorescence exciter load shows high concentrations of pathogens both in the MEEK silk layer as well as in foam linkers. Overall split-thickness grafts according to the MEEK technique showed a higher healing rate compared to MESH technique. Screening of burns wounds with autofluorescence imaging can be helpful for an additive wound assessment. Split-thickness graft covers should be applied only for a minimum time period required to ensure stable grafting.


Assuntos
Bactérias , Queimaduras , Fluorescência , Queimaduras/microbiologia , Humanos , Projetos Piloto , Transplante de Pele
16.
BMC Res Notes ; 12(1): 28, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30646938

RESUMO

OBJECTIVE: The present study aimed to determine the prevalence of virulence factors and antimicrobial resistance profile of Pseudomonas aeruginosa strains isolated from Iranian burn patients. RESULTS: This cross-sectional study performed on 100 P. aeruginosa isolates which were recovered from burn wound specimens in 2014-2015. All presumptive isolates were identified by standard microbiologic tests. Antimicrobial susceptibility test was carried out by disk diffusion method. The presence of virulence genes was determined by PCR method. Antibiotic susceptibility results revealed that the isolates were mostly susceptible to amikacin (61%), ceftazidime (60%), and imipenem (55%). Moreover, 59% of the isolates were multi-drug resistance (MDR). The most prevalent MDR pattern was aminoglycosides-penicillins-fluoroquinolones-carbapenems (15%). The presence of exoT, exoY, exoS and exoU genes was detected in 100%, 100%, 59%, and 41% of the tested isolates, respectively. Results points out the pattern of MDR and genetic diversity of type III secretion system among P. aeruginosa strains isolated from the burn population. Overall, the association of MDR and the presence of the specific virulence genes can be a predictive marker for the persistence of these isolates in the hospitals and subsequently a worse clinical condition for the affected patients.


Assuntos
ADP Ribose Transferases/genética , Antibacterianos , Proteínas de Bactérias/genética , Toxinas Bacterianas/genética , Unidades de Queimados , Queimaduras/microbiologia , Farmacorresistência Bacteriana Múltipla/genética , Proteínas Ativadoras de GTPase/genética , Glucosiltransferases/genética , Pseudomonas aeruginosa/genética , Sistemas de Secreção Tipo III , Fatores de Virulência/genética , Estudos Transversais , Humanos , Irã (Geográfico) , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa/isolamento & purificação
17.
Drug Deliv Transl Res ; 9(4): 748-763, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30652257

RESUMO

Staphylococcus aureus (SA) and methicillin-resistant Staphylococcus aureus (MRSA) have been a major cause of morbidity in thermally injured patients. The skin barrier gets disrupted and loss of immunity further makes burn sites an easy target for bacterial colonization. In the current study, combined potential of lipid-polymer hybrid nanoparticles (LPHNs) with fusidic acid was explored as a promising strategy toward combating resistant bacteria in burn wound infection sites. The developed systems exhibited particle size (310.56 ± 5.22 nm), zeta potential (24.3 ± 4.18 mV) and entrapment efficiency (78.56 ± 3.56%) with a spherical shape. The hybrid nanoparticles were further gelled into carbopol and demonstrated better permeation (76.53 ± 1.55%) and retention characteristics (56.41 ± 4.67%) as compared to the conventional formulation. The topical delivery of FA into the skin layers by FA-LPHN gel was found to be significantly higher (p < 0.05) compared to FA-CC. The in vivo potential was further assessed in murine burn wound model inflicted with MRSA 33591 bacterium with the determination of parameters like bacterial burden, wound contraction, morphological and histopathological examination of wounds. The bacterial count decreased drastically in FA-LPHN gel group (5.22 log CFU/mL) on day 3 with significant difference in comparison to FA-CC. The wound size reduction in FA-LPHN gel (68.70 ± 3.65%) was higher as compared to FA-CC (73.30 ± 4.23%) and control groups (83.30 ± 4.40%) on day 5. The current study presents a safe and effective formulation strategy for the treatment of MRSA-infected burn wounds by providing moist environment and prevention from bacterial infection.


Assuntos
Queimaduras/tratamento farmacológico , Portadores de Fármacos/administração & dosagem , Ácido Fusídico/administração & dosagem , Staphylococcus aureus Resistente à Meticilina , Nanopartículas/administração & dosagem , Pele/metabolismo , Infecções Estafilocócicas/tratamento farmacológico , Infecção dos Ferimentos/tratamento farmacológico , Animais , Queimaduras/imunologia , Queimaduras/microbiologia , Citocinas/imunologia , Portadores de Fármacos/farmacocinética , Feminino , Ácido Fusídico/farmacocinética , Géis , Lipídeos/administração & dosagem , Lipídeos/farmacocinética , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/crescimento & desenvolvimento , Camundongos Endogâmicos BALB C , Polímeros/administração & dosagem , Polímeros/farmacocinética , Ratos Wistar , Pele/efeitos dos fármacos , Pele/imunologia , Absorção Cutânea , Infecções Estafilocócicas/imunologia , Infecções Estafilocócicas/microbiologia , Infecção dos Ferimentos/imunologia , Infecção dos Ferimentos/microbiologia
18.
Photodiagnosis Photodyn Ther ; 25: 406-413, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30684672

RESUMO

PURPOSE: Burn patients are particularly susceptible to microbial infection. Staphylococcus aureus causes burn wound, impetigo and cellulitis. Although sub-lethal antimicrobial photodynamic therapy (aPDT) would not result in microorganism killing, it can considerably influence microbial virulence factor. METHODS: Twelve methicillin-resistant S. aureus (MRSA) and methicillin-sensitive S. aureus (MSSA) isolated from burns patients. To determine the sub-lethal dose of aPDT, 12 clinical isolates of S. aureus photosensitized with 100 µg ml -1 toluidine blue O (TBO) and irradiated by light emitting diode (LED) with a wavelength of 630 ± 10 nm and energy densities of 52.0, 104.1, and 156.2 J/cm2, then bacterial viability was measured. The effects of sub-lethal aPDT on the expression levels of ica ABCD and ica R genes were assessed by quantitative Real-time PCR (qRT-PCR) method. RESULT: Fifty and 100 µg ml-1 of TBO significantly reduced the mean cell survival in the MRSA (2.5 - 3 log10) and MSSA (2.75-3.1 log10) isolates. The average expression levels of icaA, ica B, ica C, and ica D in the MRSA and MSSA isolates were decreased by (12, 14, 11, and 9) and (13, 14.5, 12, and 9.5) fold change, respectively (P < 0.05). However, the expression of ica R gene was decreased by 6 and 8 folds change in MRSA and MSSA, respectively. CONCLUSION: The potential of TBO-mediated aPDT could reduce the expression of ica ABCD as important genes involved in biofilm formation and ica R gene as a repressor of the ica operon. Therefore, the use of aPDT agents as a complementary therapy in wound infections of burn patients is recommended.


Assuntos
Biofilmes/efeitos dos fármacos , Queimaduras/microbiologia , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Infecção dos Ferimentos/microbiologia , Subfamília D de Transportador de Cassetes de Ligação de ATP/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/genética , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase em Tempo Real , Staphylococcus aureus/genética , Cloreto de Tolônio/farmacologia
19.
Microb Drug Resist ; 25(2): 193-202, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30281385

RESUMO

BACKGROUND: Morbidity and mortality due to multidrug-resistant (MDR) bacteria are of great concern in burn patients. In this critical condition, synergism between antimicrobial peptides and conventional antibiotics would be a promising strategy. Accordingly, this study aimed to determine the therapeutic value of melittin as a natural peptide by examining its synergistic effect with conventional antibiotics against MDR isolates of Acinetobacter baumannii and Pseudomonas aeruginosa. MATERIALS AND METHODS: Fifteen clinical isolates for each kind of bacteria were collected from burn patients. Antibiotic susceptibility of all isolates was evaluated by disk diffusion method. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration for melittin, colistin, doripenem, doxycycline, and ceftazidime were also examined. Fractional inhibitory concentration (FIC) of melittin in combination with the antibiotics was determined for six MDR isolates. The cytotoxicity of melittin in combination with the antibiotics was examined on a normal human cell line. RESULTS: The geometric means of MIC (GMMIC) for melittin and doripenem after combination were reduced to 61.5- and 51.5-fold, respectively, against MDR A. baumannii isolates. These reductions for melittin-doripenem and melittin-ceftazidime against MDR P. aeruginosa isolates were (63.5 and 58)-fold and (16 and 11)-fold, respectively. FIC for melittin-doripenem against A. baumannii and FIC for melittin-doripenem and melittin-ceftazidime against P. aeruginosa strains were ≤0.5. This issue caused a decrease of up to 104-, 68-, and 17-fold, respectively, in the cytotoxicity of melittin. CONCLUSION: In conclusion, the synergism of melittin at its nontoxic dose with doripenem and ceftazidime could be of great therapeutic value as a topical drug against burn infections caused by MDR bacteria.


Assuntos
Acinetobacter baumannii/efeitos dos fármacos , Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Meliteno/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Infecções por Acinetobacter/microbiologia , Queimaduras/microbiologia , Ceftazidima/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Doripenem/farmacologia , Sinergismo Farmacológico , Humanos , Testes de Sensibilidade Microbiana , Infecções por Pseudomonas/microbiologia
20.
Infect Disord Drug Targets ; 19(3): 269-273, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30179147

RESUMO

INTRODUCTION: Aeromonas have recently emerged as opportunistic pathogens and only a few studies are available regarding the isolation of these bacteria from burn wound infections. This study aimed at isolating Aeromonas as an infrequent cause of infection in this group of immunocompromised patients. METHODS: A total of 300 samples were collected from the wounds of burn patients hospitalized in Gotbodin Shirazi Burn Center in 2013. The samples were cultured on Aeromonas specific media and then confirmed using standard biochemical tests and 16S rRNA gene amplification and sequencing. The antibiotic susceptibility of the isolates was determined using the disk diffusion and broth microdilution methods. RESULTS: Biochemical tests demonstrated five presumptive samples of Aeromonas, while, molecular testing confirmed only three. All isolates were resistant to ampicillin-sulbactam, erythromycin, oxacillin, and vancomycin. However, they were susceptible to gentamicin, meropenem, nitrofurantoin, chloramphenicol, cephalexin, and cefotaxime. Two Aeromonas veronii isolates were resistant to sulfamethoxazole-trimethoprim and sensitive to nalidixic acid, while Aeromonas bestiarum was sensitive to the former and resistant to the latter antibiotics. Lastly, only one of the A. veronii isolates was found to be resistant to tetracycline. CONCLUSION: This study is the first to report on the isolation of Aeromonas spp. from burn patients in Iran. Moreover, this is the first report of isolating A. bestiarum from burn wounds. The results of this study confirm earlier findings that the use of molecular methods is essential to accurately identify these bacteria.


Assuntos
Aeromonas/genética , Aeromonas/isolamento & purificação , Queimaduras/microbiologia , Infecção dos Ferimentos/microbiologia , Adulto , Aeromonas/efeitos dos fármacos , Antibacterianos/farmacologia , Coinfecção/microbiologia , Estudos Transversais , Farmacorresistência Bacteriana , Feminino , Humanos , Hospedeiro Imunocomprometido , Irã (Geográfico) , Masculino , Testes de Sensibilidade Microbiana , RNA Ribossômico 16S/genética , Adulto Jovem
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