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1.
Int J Nanomedicine ; 15: 6935-6944, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33061360

RESUMO

Introduction: Nanoparticle solutions have been studied to improve antimicrobial effect. The aim of this study was to develop, characterize, and evaluate the in vitro and in vivo antiseptic efficacy of 0.25% aqueous-based chlorhexidine nanoemulsion (NM-Cl 0.25% w/v). Methods: The NM-Cl 0.25% w/v (2.5mg/mL) and free chlorhexidine nanoemulsion (FCN; same composition of NM-Cl without the molecule of chlorhexidine) were synthetized by the spontaneous emulsification method. Characterization analyses of physical and chemical properties were performed. The NM-Cl 0.25% w/v was compared with chlorhexidine 0.5% alcohol base (CS-Cl 0.5%) in vitro studies (microdilution study and kill curve study), and in vivo study (antisepsis of rats dorsum). Kruskal-Wallis test was used between groups and inside the same group, at different sample times and the Mann-Whitney test was performed when difference was detected. Results: The NM-Cl 0.25% w/v presented adequate physicochemical characteristics for a nanoemulsion, revealing a more basic pH than FCN and difference between zeta potential of NM-Cl 0.25% w/v and FCN. The NM-Cl 0.25% w/v and CS-Cl 0.5% solutions were more effective on Gram-positive than on Gram-negative bacteria (p≤0.05). NM-Cl 0.25% w/v presented upper antiseptic effect in the microdilution study and residual antiseptic effect was maintained for a longer time when compared to CS-Cl 0.5% (kill curve study). The four-fold (minimal inhibitory concentration) of NM-Cl 0.25% were the formulations with most durable effect within those tested, presenting residual effect until T6 for both bacteria. In the in vivo study, both formulations (NM-Cl 0.25% w/v and CS-Cl 0.5%) had a reduction of the microorganisms in the skin of the rats (p<0.0001) not revealing any difference between the formulations at different times, showing the antiseptic effect of NM-Cl (p≤0.05). Conclusion: Both in vitro and in vivo experiments demonstrated that NM-Cl showed promising future as an antiseptic for cutaneous microbiota.


Assuntos
Anti-Infecciosos Locais/farmacologia , Clorexidina/farmacologia , Emulsões/química , Nanoestruturas/química , Animais , Anti-Infecciosos Locais/química , Clorexidina/química , Emulsões/farmacologia , Etanol/química , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Masculino , Testes de Sensibilidade Microbiana , Nanoestruturas/uso terapêutico , Ratos Wistar , Pele/efeitos dos fármacos , Pele/microbiologia
2.
PLoS One ; 15(9): e0238998, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32941473

RESUMO

The frequent contact people have with liquids containing pathogenic microorganisms provides opportunities for disease transmission. In this work, we quantified the transfer of bacteria-using E. coli as a model- from liquid to skin, estimated liquid retention on the skin after different contact activities (hand immersion, wet-cloth and wet-surface contact), and estimated liquid transfer following hand-to-mouth contacts. The results of our study show that the number of E. coli transferred to the skin per surface area (n [E. coli/cm2]) can be modeled using n = C (10-3.38+h), where C [E. coli/cm3] is the concentration of E. coli in the liquid, and h [cm] is the film thickness of the liquid retained on the skin. Findings from the E. coli transfer experiments reveal a significant difference between the transfer of E. coli from liquid to the skin and the previously reported transfer of viruses to the skin. Additionally, our results demonstrate that the time elapsed since the interaction significantly influences liquid retention, therefore modulating the risks associated with human interaction with contaminated liquids. The findings enhance our understanding of liquid-mediated disease transmission processes and provide quantitative estimates as inputs for microbial risk assessments.


Assuntos
Adsorção/fisiologia , Dermatopatias Bacterianas/transmissão , Pele/microbiologia , Fenômenos Biológicos , Transmissão de Doença Infecciosa/prevenção & controle , Escherichia coli/patogenicidade , Mãos , Humanos , Modelos Teóricos , Água/química , Microbiologia da Água
3.
Int J Syst Evol Microbiol ; 70(10): 5417-5424, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32886591

RESUMO

A Gram-stain-negative, moderately halophilic strain, designated strain L5T, was isolated from wetsalted hides collected from Chengdu, south-west PR China. The cells were motile, facultative aerobic, short rod-shaped and non-endospore-forming. Growth of strain L5T occurred at pH 6-10 (optimum, pH 8), 10-45 °C (optimum, 30 °C) and in the presence of 1-17 % (w/v) NaCl (optimum, 10 %). Results of phylogenetic analyses based on 16S rRNA, gyrB and rpoD gene sequences and its genome revealed that strain L5T belonged to the genus Halomonas. Strain L5T was found to be most closely related to the type strains of Halomonas saliphila, Halomonas lactosivorans, Halomonas kenyensis, Halomonas daqingensis and Halomonas desiderata (98.8, 98.6, 98.3, 97.9 and 97.4 % 16S rRNA gene sequence similarity, respectively). The draft genome was approximately 4.2 Mb in size with a G+C content of 63.5 mol%. The average nucleotide identity (ANI) and digital DNA-DNA hybridization values among strain L5T and the selected Halomonas species were 83.3-88.9 % (ANIm), 71.1-87.3 % (ANIb) and 20.2-34.6 %, which are below the recommended cutoff values. Major fatty acids were C16 : 0, C16 : 1 ω7c, C18 : 1 ω7c and C19 : 0 cyclo ω8c and the predominant ubiquinone was Q-9, with minor ubiquinone Q-8 also present. The phospholipid profile consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, four unidentified aminophospholipids and three unidentified phospholipids. Based on the mentioned polyphasic taxonomic evidence, strain L5T represents a novel species within the genus Halomonas, for which Halomonas pellis sp. nov. is proposed. The type strain is L5T (=CGMCC 1.17335T=KCTC 72573T).


Assuntos
Cabras/microbiologia , Halomonas/classificação , Filogenia , Pele/microbiologia , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Genes Bacterianos , Halomonas/isolamento & purificação , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Cloreto de Sódio , Ubiquinona/química
4.
PLoS One ; 15(9): e0235370, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32915779

RESUMO

Controlled experiments are one approach to understanding the pathogenicity of etiologic agents to susceptible hosts. The recently discovered fungal pathogen, Batrachochytrium salamandrivorans (Bsal), has resulted in a surge of experimental investigations because of its potential to impact global salamander biodiversity. However, variation in experimental methodologies could thwart knowledge advancement by introducing confounding factors that make comparisons difficult among studies. Thus, our objective was to evaluate if variation in experimental methods changed inferences made on the pathogenicity of Bsal. We tested whether passage duration of Bsal culture, exposure method of the host to Bsal (water bath vs. skin inoculation), Bsal culturing method (liquid vs. plated), host husbandry conditions (aquatic vs. terrestrial), and skin swabbing frequency influenced diseased-induced mortality in a susceptible host species, the eastern newt (Notophthalmus viridescens). We found that disease-induced mortality was faster for eastern newts when exposed to a low passage isolate, when newts were housed in terrestrial environments, and if exposure to zoospores occurred via water bath. We did not detect differences in disease-induced mortality between culturing methods or swabbing frequencies. Our results illustrate the need to standardize methods among Bsal experiments. We provide suggestions for future Bsal experiments in the context of hypothesis testing and discuss the ecological implications of our results.


Assuntos
Quitridiomicetos/patogenicidade , Micoses/veterinária , Urodelos/microbiologia , Animais , Técnicas de Cultura de Células , Quitridiomicetos/isolamento & purificação , Quitridiomicetos/fisiologia , Micoses/microbiologia , Micoses/patologia , Pele/microbiologia , Pele/patologia , Coloração e Rotulagem , Urodelos/fisiologia
5.
Med Microbiol Immunol ; 209(6): 669-680, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32880037

RESUMO

The ability of bacteria to aggregate and form biofilms impairs phagocytosis by polymorphonuclear leukocytes (PMNs). The aim of this study was to examine if the size of aggregates is critical for successful phagocytosis and how bacterial biofilms evade phagocytosis. We investigated the live interaction between PMNs and Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli and Staphylococcus epidermidis using confocal scanning laser microscopy. Aggregate size significantly affected phagocytosis outcome and larger aggregates were less likely to be phagocytized. Aggregates of S. epidermidis were also less likely to be phagocytized than equally-sized aggregates of the other three species. We found that only aggregates of approx. 5 µm diameter or smaller were consistently phagocytosed. We demonstrate that planktonic and aggregated cells of all four species significantly reduced the viability of PMNs after 4 h of incubation. Our results indicate that larger bacterial aggregates are less likely to be phagocytosed by PMNs and we propose that, if the aggregates become too large, circulating PMNs may not be able to phagocytose them quickly enough, which may lead to chronic infection.


Assuntos
Biofilmes , Escherichia coli/fisiologia , Neutrófilos/fisiologia , Fagocitose , Pseudomonas aeruginosa/fisiologia , Staphylococcus aureus/fisiologia , Staphylococcus epidermidis/fisiologia , Escherichia coli/ultraestrutura , Humanos , Pseudomonas aeruginosa/ultraestrutura , Pele/microbiologia , Staphylococcus aureus/ultraestrutura , Staphylococcus epidermidis/ultraestrutura
6.
Adv Exp Med Biol ; 1265: 187-199, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32761577

RESUMO

Amino acids are the building blocks of all proteins, including the most abundant fibrous proteins in the skin, as keratins, collagen and elastin. Sagging and wrinkled skin are features of chronic sun-damaged and aged uncared skin, and they are mainly associated with the deterioration of collagen and elastic fibers. The maintenance of skin structures by self-repair processes is essential to skin health. Thus, amino acids significantly impact the appearance of the skin. Amino acids are important nutrients required for (a) wound healing promotion and repair of the damaged skin; (b) acid-base balance and water retention in cellular layers, such as stratum corneum; (c) protection against sunlight damage; (d) maintenance of an appropriate skin microbiome. This review highlights the contribution of all proteinogenic amino acids and some related metabolites to the skin structures as constituents of the main cutaneous proteins or as signaling molecules for the regulation and determination of skin physiology.


Assuntos
Aminoácidos/metabolismo , Pele/metabolismo , Colágeno , Elastina , Humanos , Queratinas , Pele/citologia , Pele/microbiologia , Envelhecimento da Pele
7.
Mol Ecol ; 29(17): 3167-3169, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32745298

RESUMO

What happens when two emergent diseases infect the same host? In a From the Cover article in this issue of Molecular Ecology, McDonald et al. (2020) compare transcriptomic responses to co-infection by the two chytrid fungi in the skin, liver and spleen of Eastern newts (Notophthalmus viridescens). Novel molecular tools, such as high-throughput DNA sequencing for genome discovery and transcriptomics, have revolutionized our understanding of host-pathogen interactions and disease ecology (Güimil et al. 2005; Rosenblum et al. 2012). For example, epidemiologists are using genomic data to track the spread of the emergent SARS-CoV-2 in real time, both locally and globally. RNA sequencing (RNA-Seq) is routinely employed to study response to disease in humans, improving disease diagnostics, profiling and development of intervention strategies. Transcriptomic profiles may be particularly informative for emergent diseases, whose pathologies and effect on host phenotype are poorly known. Fungal pathogens increasingly threaten a variety of wild and domesticated organisms (Fisher et al. 2012), and two chytrid fungi attacking amphibians are causing one of the worst losses of vertebrate biodiversity ever recorded (Scheele et al. 2019).


Assuntos
Quitridiomicetos/imunologia , Micoses/veterinária , Salamandridae/imunologia , Animais , Coinfecção/imunologia , Perfilação da Expressão Gênica , Humanos , Fígado/microbiologia , Micoses/imunologia , Micoses/microbiologia , Salamandridae/genética , Salamandridae/microbiologia , Pele/microbiologia , Baço/microbiologia , Transcriptoma/genética
8.
PLoS One ; 15(8): e0235948, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32785216

RESUMO

INTRODUCTION: Surgical site infection is one of the most severe complications of surgical treatments. However, the optimal procedure to prevent such infections remains uninvestigated. Ultraviolet radiation C (UVC) with a short wavelength has a high bactericidal effect; however, it is cytotoxic. Nonetheless, given that UVC with a wavelength of 222 nm reaches only the stratum corneum, it does not affect the skin cells. This study aimed to investigate the safety of 222-nm UVC irradiation and to examine its skin sterilization effect in healthy volunteers. METHODS: This trial was conducted on 20 healthy volunteers. The back of the subject was irradiated with 222-nm UVC at 50-500 mJ/cm2, and the induced erythema (redness of skin) was evaluated. Subsequently, the back was irradiated with a maximum amount of UVC not causing erythema, and the skin swabs before and after the irradiation were cultured. The number of colonies formed after 24 hours was measured. In addition, cyclobutene pyrimidine dimer (CPD) as an indicator of DNA damage was measured using skin tissues of the nonirradiated and irradiated regions. RESULTS: All subjects experienced no erythema at all doses. The back of the subject was irradiated at 500 mJ/cm2, and the number of bacterial colonies in the skin swab culture was significantly decreased by 222-nm UVC irradiation. The CPD amount produced in the irradiated region was slightly but significantly higher than that of the non-irradiated region. CONCLUSION: A 222-nm UVC at 500 mJ/cm2 was a safe irradiation dose and possessed bactericidal effects. In the future, 222-nm UVC irradiation is expected to contribute to the prevention of perioperative infection.


Assuntos
Dano ao DNA/efeitos da radiação , Microbiota/efeitos da radiação , Pele/efeitos da radiação , Esterilização/métodos , Raios Ultravioleta/efeitos adversos , Adulto , Dorso , Biópsia , Contagem de Colônia Microbiana , Eritema/diagnóstico , Eritema/etiologia , Voluntários Saudáveis , Humanos , Masculino , Dímeros de Pirimidina/análise , Dímeros de Pirimidina/efeitos da radiação , Pele/microbiologia , Infecção da Ferida Cirúrgica/microbiologia , Infecção da Ferida Cirúrgica/prevenção & controle , Resultado do Tratamento
9.
Bone Joint J ; 102-B(7_Supple_B): 52-56, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32600208

RESUMO

AIMS: Of growing concern in arthroplasty is the emergence of atypical infections, particularly Cutibacterium (formerly Propionibacterium) sp. infections. Currently, the dermal colonization rate of Cutibacterium about the hip is unknown. Therefore, the aim of this study was to investigate colonization rates of Cutibacterium sp. at locations approximating anterior and posterolateral approaches to the hip joint. METHODS: For this non-randomized non-blinded study, 101 adult patients scheduled for hip or knee surgery were recruited. For each, four 3 mm dermal punch biopsies were collected after administration of anaesthesia, but prior to antibiotics. Prebiopsy skin preparation consisted of a standardized preoperative 2% chlorhexidine skin cleansing protocol and an additional 70% isopropyl alcohol mechanical skin scrub immediately prior to biopsy collection. Two skin samples 10 cm apart were collected from a location approximating a standard direct anterior skin incision, and two samples 10 cm apart were collected from a lateral skin incision (suitable for posterior, direct-lateral, or anterolateral approaches). Samples were cultured for two weeks using a protocol optimized for Cutibacterium. RESULTS: A total of 23 out of 404 cultures (collected from 101 patients) were positive for a microorganism, with a total of 22 patients having a positive culture (22%). Overall, 15 of the cultures in 14 patients were positive for Cutibacterium sp. (65%), of which Cutibacterium acnes comprised the majority (n = 13; 87%). Other isolated microorganisms include coagulase-negative Staphylococcus (n = 6), Clostridium (n = 1), and Corynebacterium (n = 1). Of all positive cultures, 15 were obtained from the anterior location (65%), of which seven (60%) were from the most proximal biopsy location. However, these findings were not statistically significant (anterior vs lateral, p = 0.076; proximal vs distal, p =0.238). CONCLUSION: Approximately 14% (14/101) of the patients demonstrated a positive Cutibacterium colonization about the hip, the majority anteriorly. Given the high colonization rate of Cutibacterium, alternative skin preparations for total hip arthroplasty should be considered. Cite this article: Bone Joint J 2020;102-B(7 Supple B):52-56.


Assuntos
Quadril/microbiologia , Propionibacteriaceae/isolamento & purificação , Pele/microbiologia , Coxa da Perna/microbiologia , Adulto , Idoso , Artroplastia de Quadril , Biópsia , Clostridium/isolamento & purificação , Corynebacterium/isolamento & purificação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Staphylococcus/isolamento & purificação
11.
Proc Natl Acad Sci U S A ; 117(28): 16465-16474, 2020 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-32601220

RESUMO

Under steady-state conditions, the immune system is poised to sense and respond to the microbiota. As such, immunity to the microbiota, including T cell responses, is expected to precede any inflammatory trigger. How this pool of preformed microbiota-specific T cells contributes to tissue pathologies remains unclear. Here, using an experimental model of psoriasis, we show that recall responses to commensal skin fungi can significantly aggravate tissue inflammation. Enhanced pathology caused by fungi preexposure depends on Th17 responses and neutrophil extracellular traps and recapitulates features of the transcriptional landscape of human lesional psoriatic skin. Together, our results propose that recall responses directed to skin fungi can directly promote skin inflammation and that exploration of tissue inflammation should be assessed in the context of recall responses to the microbiota.


Assuntos
Arthrodermataceae/fisiologia , Microbiota , Psoríase/imunologia , Pele/microbiologia , Animais , Arthrodermataceae/classificação , Arthrodermataceae/genética , Arthrodermataceae/isolamento & purificação , Armadilhas Extracelulares/imunologia , Armadilhas Extracelulares/microbiologia , Feminino , Humanos , Imunidade , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Psoríase/microbiologia , Psoríase/patologia , Pele/imunologia , Pele/patologia , Simbiose , Células Th17/imunologia
12.
Dermatol Online J ; 26(4)2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32621684

RESUMO

Non-pigmented rapidly growing mycobacteria are nontuberculous mycobacteria (NTM) capable of producing disease. We report a case of tattoo-associated NTM infection with a novel species: Mycobacterium mageritense. A 48-year-old man presented with a two-week history of a papulopustular eruption on the shaded areas of a tattoo that had been placed five weeks prior while in the Philippines. Histopathology from punch biopsies revealed suppurative granulomatous dermatitis with acid fast bacilli present. Subsequent matrix assisted laser desorption/ionization time of flight (MALDI-TOF) mass spectrometer identified the bacteria as Mycobacterium margeritense. After consultation with infectious disease specialists and culture susceptibilities, the patient was treated with three months of dual antibiotic therapy with minocycline and moxifloxacin. The patient experienced a slow but complete resolution of clinical skin findings after the course of treatment. Since discovery in 1997, M. mageritense infection has been demonstrated in a wide spectrum of disease, predominantly skin and soft tissue infections. The species has not been previously implicated in tattoo-associated NTM infections. M. mageritense should be considered as a specific type of mycobacteria in the differential diagnosis for tattoo-associated NTM infections owing to differences in antibiotic susceptibilities compared to other NTM species.


Assuntos
Infecções por Mycobacterium não Tuberculosas/diagnóstico , Micobactérias não Tuberculosas/isolamento & purificação , Tatuagem/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Infecções por Mycobacterium não Tuberculosas/microbiologia , Infecções por Mycobacterium não Tuberculosas/patologia , Pele/microbiologia , Pele/patologia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
13.
Dermatol Online J ; 26(3)2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32609438

RESUMO

Reflectance confocal microscopy (RCM) is a noninvasive real-time imaging technique that has been widely used for the diagnosis of skin cancer. More recently, it has been reported as a useful tool for the diagnosis and management of several inflammatory and infectious skin disorders. This article provides an overview of the current available applications of RCM use in cutaneous infections and infestations. PubMed was used to search the following terms in various combinations: reflectance confocal microscopy, skin, hair, nail, infection, parasitosis, mycosis, virus, bacteria. All papers were accordingly reviewed. In most cutaneous infections or infestations, the main alterations are found in the epidermis and upper dermis, where the accuracy of confocal microscopy is nearly similar to that of histopathology. The high resolution of this technique allows the visualization of most skin parasites, fungi, and a few bacteria. Although viruses cannot be identified because of their small size, viral cytopathic effects can be observed on keratinocytes. In addition, RCM can be used to monitor the response to treatment, thereby reducing unnecessary treatments.


Assuntos
Microscopia Confocal/métodos , Dermatopatias Infecciosas/diagnóstico por imagem , Dermatopatias Parasitárias/diagnóstico por imagem , Feminino , Humanos , Masculino , Pele/diagnóstico por imagem , Pele/microbiologia , Pele/parasitologia , Pele/patologia , Dermatopatias Infecciosas/patologia , Dermatopatias Parasitárias/patologia
14.
Ann Allergy Asthma Immunol ; 125(5): 528-534, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32474160

RESUMO

OBJECTIVE: To explore links between biodiversity on all scales and allergic disease as a measure of immune dysregulation. DATA SOURCES: PubMed and Web of Science were searched using the keywords biodiversity, nature relatedness, allergic disease, microbiome, noncommunicable diseases, coronavirus disease 2019, and associated terms. STUDY SELECTIONS: Studies were selected based on relevance to human health and biodiversity. RESULTS: Contact with natural environments enriches the human microbiome, promotes regulated immune responses, and protects against allergy and both acute and chronic inflammatory disorders. These important links to ecopsychological constructs of the extinction of experience, which indicates that loss of direct, personal contact with biodiversity (wildlife and the more visible elements of the natural world), might lead to emotional apathy and irresponsible behaviors toward the environment. CONCLUSION: The immune system is a useful early barometer of environmental effects and, by means of the microbiome, is a measure of the way in which our current experiences differ from our ancestral past. Although we would benefit from further research, efforts to increase direct, personal contact with biodiversity have clear benefits for multiple aspects of physical and mental health, the skin and gut microbiome, immune function, food choices, sleep, and physical activity and promote environmental responsibility.


Assuntos
Alérgenos/imunologia , Infecções por Coronavirus/prevenção & controle , Suscetibilidade a Doenças/imunologia , Hipersensibilidade/prevenção & controle , Microbiota/imunologia , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Alérgenos/administração & dosagem , Betacoronavirus/imunologia , Betacoronavirus/patogenicidade , Biodiversidade , Infecções por Coronavirus/genética , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Ecossistema , Exposição Ambiental/análise , Extinção Biológica , Trato Gastrointestinal/imunologia , Trato Gastrointestinal/microbiologia , Trato Gastrointestinal/virologia , Interação Gene-Ambiente , Humanos , Hipersensibilidade/genética , Hipersensibilidade/imunologia , Hipersensibilidade/microbiologia , Sistema Imunitário/efeitos dos fármacos , Pneumonia Viral/genética , Pneumonia Viral/imunologia , Pneumonia Viral/virologia , Pele/imunologia , Pele/microbiologia , Pele/virologia
15.
J Dairy Sci ; 103(8): 7322-7330, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32534929

RESUMO

The aim of this study was to evaluate the effect of sampling technique and milk fraction on bovine milk microbiota data and to compare the microbiota in milk to microbiota on the teat end and in the teat canal. Representative milk samples are highly important for assessment of bacteriological findings and microbiota in milk. Samples were obtained from 5 healthy lactating dairy cows at udder quarter level during 1 milking. Swab samples from the teat end and teat canal, and milk samples collected using different techniques and in different milk fractions were included. Milk was collected by hand stripping and through a teat canal cannula before and after machine milking, through a trans-teat wall needle aspirate after milking, and from udder quarter composite milk. The microbiota of the samples was analyzed with sequencing of the V1-V3 region of the 16S rRNA gene. In addition, somatic cell counts and bacterial cultivability were analyzed in the milk samples. Microbiota data were analyzed using multivariate methods, and differences between samples were tested using analysis of similarity (ANOSIM). Differences between samples were further explored via individual studies of the 10 most abundant genera. The microbiota on the teat end, in the teat canal, and in udder quarter composite milk, collected using a milking machine, differed in composition from the microbiota in milk collected directly from the udder quarter. No differences in milk microbiota composition were detected between hand-stripped milk samples, milk samples taken through a teat canal cannula, or milk samples taken as a trans-teat wall needle aspirate before or after milking. We conclude that for aseptic milk samples collected directly from the lactating udder quarter, sampling technique or milk fraction has minor effect on the microbiota composition.


Assuntos
Bactérias/isolamento & purificação , Bovinos/microbiologia , Microbiota , Leite/microbiologia , Manejo de Espécimes/veterinária , Animais , Bactérias/genética , Indústria de Laticínios , Feminino , Lactação , Glândulas Mamárias Animais/microbiologia , Pele/microbiologia
16.
BMC Infect Dis ; 20(1): 411, 2020 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-32532220

RESUMO

BACKGROUND: The prevalence of healthcare-acquired infections (HAI) and rising levels of antimicrobial resistance places significant economic and public health burdens on modern healthcare systems. A group of highly drug resistant pathogens known as the ESKAPE pathogens, along with C. difficile, are the leading causes of HAIs. Interactions between patients, healthcare workers, and environmental conditions impact disease transmission. Studying pathogen transfer under varying contact scenarios in a controlled manner is critical for understanding transmission and disinfectant strategies. In lieu of human subject research, this method has the potential to contribute to modeling the routes of pathogen transmission in healthcare settings. METHODS: To overcome these challenges, we have developed a method that utilizes a synthetic skin surrogate to model both direct (skin-to-skin) and indirect (skin-to fomite-to skin) pathogen transfer between infected patients and healthy healthcare workers. This surrogate material includes a background microbiome community simulating typical human skin flora to more accurately mimic the effects of natural flora during transmission events. RESULTS: We demonstrate the ability to modulate individual bacterial concentrations within this microbial community to mimic bacterial concentrations previously reported on the hands of human subjects. We also explore the effect of various decontamination approaches on pathogen transfer between human subjects, such as the use of handwashing or surface disinfectants. Using this method, we identify a potential outlier, S. aureus, that may persist and retain viability in specific transfer conditions better than the overall microbial community during decontamination events. CONCLUSIONS: Our work describes the development of an in vitro method that uses a synthetic skin surrogate with a defined background microbiota to simulate skin-to-skin and skin-to fomite-to skin contact scenarios. These results illustrate the value of simulating a holistic microbial community for transfer studies by elucidating differences in different pathogen transmission rates and resistance to common decontamination practices. We believe this method will contribute to improvements in pathogen transmission modeling in healthcare settings and increase our ability to assess the risk associated with HAIs, although additional research is required to establish the degree of correlation of pathogen transmission by skin or synthetic alternatives.


Assuntos
Infecção Hospitalar/microbiologia , Infecção Hospitalar/transmissão , Modelos Biológicos , Clostridium difficile , Infecção Hospitalar/prevenção & controle , Descontaminação/métodos , Resistência Microbiana a Medicamentos , Fômites/microbiologia , Humanos , Viabilidade Microbiana , Microbiota , Pele/microbiologia , Especificidade da Espécie
17.
J Water Health ; 18(3): 314-330, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32589618

RESUMO

Cyanobacteria are ancient photosynthetic microorganisms that shaped today's atmosphere. Anthropocentric and irresponsible activities are changing the atmosphere which favor the frequent occurrence and mass development of cyanobacteria. Extensive cyanobacterial blooming causes numerous problems, including negative effects on human skin. Climate change, depletion of ozone layer, and the increased ultraviolet radiation also affect the skin and lead to more frequent occurrence of skin cancer. This research, for the first time, attempts to establish a connection between these two factors, or whether, in addition to ultraviolet radiation, cyanobacteria can influence the incidence of melanoma. With this objective in mind, an epidemiological investigation was conducted in Vojvodina, Serbia. It was observed that the incidence of melanoma was higher in municipalities where water bodies used for recreation, irrigation and fishing are blooming; however, results could be considered as inconclusive, because of the restrictions in the cancer database. Nevertheless, results gathered from the reviewed literature support the hypothesis that cyanobacteria could be a new potential risk factor for melanoma, while climate change could be a catalyst that converts these potential risk factors into cofactors, which act synergistically with the main risk factor - ultraviolet radiation - and induce an increase of melanoma incidence.


Assuntos
Cianobactérias , Pele/microbiologia , Mudança Climática , Humanos , Incidência , Ozônio , Neoplasias Cutâneas , Raios Ultravioleta
18.
Clin Dermatol ; 38(2): 152-159, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32513396

RESUMO

Nocardiosis is caused by Gram-positive aerobic bacilli of the Nocardia genus, which are saprophytes living in the soil. It is a rare and opportunist disease with a localized or disseminated infection. When occurring in patients who are immunocompromised, involvement is usually systemic, most commonly represented by pulmonary disease. It can also be acquired through direct inoculation, entailing primary skin and subcutaneous tissue infections, frequently presenting as a localized nodular process. Cutaneous nocardiosis can manifest as a lymphocutaneous infection, actinomycetoma, superficial skin infection, or secondary infection from hematogenic dissemination. Diagnosis is made by identification of the organism in the culture of a clinical sample. Staining for acid-alcohol-resistant bacteria and, especially, Gram staining, is particularly relevant to obtain a rapid and presumptive diagnosis, while awaiting culture results. First-line medication is sulfamethoxazole-trimethoprim, which may be used with other antimicrobials, if necessary. Nocardiosis may be considered a major mimicker of several cutaneous diseases that present difficult, and often, delayed diagnoses.


Assuntos
Nocardiose/diagnóstico , Nocardiose/patologia , Pele/patologia , Diagnóstico Diferencial , Violeta Genciana , Humanos , Hospedeiro Imunocomprometido , Nocardia/isolamento & purificação , Nocardiose/tratamento farmacológico , Nocardiose/microbiologia , Fenazinas , Pele/microbiologia , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico
19.
Am J Surg Pathol ; 44(9): 1274-1281, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32568824

RESUMO

Syphilis is a sexually transmitted disease caused by the spirochetal bacterium Treponema pallidum that has been of public health concern for centuries. In the United States, it is currently a reportable disease and one which is recently generating increasing case numbers especially in at risk populations of immune deficiency and men who have sex with men. The present series examines biopsies from 13 patients collected over a 12-year period from a general hospital network in north suburban Cook County, Illinois. There were 13 patients (11 male: 2 female) with varied presentations, including primary ulcerated anogenital chancres, mucosal lesions, peculiar rashes, and alopecia. The reason(s) for biopsy were not clear from the clinical record, as a clinical consideration of syphilis was recorded in only 3 cases. Histologic examination of the mucocutaneous lesions encompassed a spectrum of findings including ulceration, psoriasiform hyperplasia, intense mixed band-like inflammation at the dermal-epidermal junction with a prominent plasma cell component. The contemporary availability of an effective immunostain is a valuable diagnostic adjunct. The organisms generally parallel the intensity of the inflammatory infiltrate but the distribution may vary and rarely, organisms may be absent despite serologic confirmation. Previous corkscrew morphology of the organism described ultrastructurally is reflected in the immunostained representation. Although the diagnosis of syphilis remains a clinical one in most cases, some patients will have unusual presentations and biopsies will be done. The awareness of the pathologist will facilitate prompt and effective treatment.


Assuntos
Cancro/patologia , Mucosa Intestinal/patologia , Mucosa Bucal/patologia , Reto/patologia , Pele/patologia , Sífilis Cutânea/patologia , Treponema pallidum/patogenicidade , Adulto , Alopecia/microbiologia , Biópsia , Cancro/microbiologia , Feminino , Interações Hospedeiro-Patógeno , Humanos , Illinois , Mucosa Intestinal/microbiologia , Masculino , Pessoa de Meia-Idade , Mucosa Bucal/microbiologia , Valor Preditivo dos Testes , Reto/microbiologia , Pele/microbiologia , Sífilis Cutânea/microbiologia , Adulto Jovem
20.
Proc Natl Acad Sci U S A ; 117(27): 15884-15894, 2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-32576698

RESUMO

The skin of humans and animals is colonized by commensal and pathogenic fungi and bacteria that share this ecological niche and have established microbial interactions. Malassezia are the most abundant fungal skin inhabitant of warm-blooded animals and have been implicated in skin diseases and systemic disorders, including Crohn's disease and pancreatic cancer. Flavohemoglobin is a key enzyme involved in microbial nitrosative stress resistance and nitric oxide degradation. Comparative genomics and phylogenetic analyses within the Malassezia genus revealed that flavohemoglobin-encoding genes were acquired through independent horizontal gene transfer events from different donor bacteria that are part of the mammalian microbiome. Through targeted gene deletion and functional complementation in Malassezia sympodialis, we demonstrated that bacterially derived flavohemoglobins are cytoplasmic proteins required for nitric oxide detoxification and nitrosative stress resistance under aerobic conditions. RNA-sequencing analysis revealed that endogenous accumulation of nitric oxide resulted in up-regulation of genes involved in stress response and down-regulation of the MalaS7 allergen-encoding genes. Solution of the high-resolution X-ray crystal structure of Malassezia flavohemoglobin revealed features conserved with both bacterial and fungal flavohemoglobins. In vivo pathogenesis is independent of Malassezia flavohemoglobin. Lastly, we identified an additional 30 genus- and species-specific horizontal gene transfer candidates that might have contributed to the evolution of this genus as the most common inhabitants of animal skin.


Assuntos
Bactérias/genética , Hemeproteínas/genética , Interações entre Hospedeiro e Microrganismos/fisiologia , Malassezia/genética , Malassezia/metabolismo , Óxido Nítrico/metabolismo , Pele/microbiologia , Animais , Bactérias/metabolismo , Cristalografia por Raios X , Ergosterol/biossíntese , Evolução Molecular , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Deleção de Genes , Regulação Fúngica da Expressão Gênica , Transferência Genética Horizontal , Hemeproteínas/química , Hemeproteínas/metabolismo , Humanos , Malassezia/classificação , Modelos Moleculares , Estresse Oxidativo/genética , Estresse Oxidativo/fisiologia , Filogenia , Pele/metabolismo , Simbiose
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