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1.
PLoS Negl Trop Dis ; 17(11): e0011742, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37983245

RESUMEN

Mayaro virus (MAYV) is a mosquito-transmitted alphavirus that causes debilitating and persistent arthritogenic disease. While MAYV was previously reported to infect non-human primates (NHP), characterization of MAYV pathogenesis is currently lacking. Therefore, in this study we characterized MAYV infection and immunity in rhesus macaques. To inform the selection of a viral strain for NHP experiments, we evaluated five MAYV strains in C57BL/6 mice and showed that MAYV strain BeAr505411 induced robust tissue dissemination and disease. Three male rhesus macaques were subcutaneously challenged with 105 plaque-forming units of this strain into the arms. Peak plasma viremia occurred at 2 days post-infection (dpi). NHPs were taken to necropsy at 10 dpi to assess viral dissemination, which included the muscles and joints, lymphoid tissues, major organs, male reproductive tissues, as well as peripheral and central nervous system tissues. Histological examination demonstrated that MAYV infection was associated with appendicular joint and muscle inflammation as well as presence of perivascular inflammation in a wide variety of tissues. One animal developed a maculopapular rash and two NHP had viral RNA detected in upper torso skin samples, which was associated with the presence of perivascular and perifollicular lymphocytic aggregation. Analysis of longitudinal peripheral blood samples indicated a robust innate and adaptive immune activation, including the presence of anti-MAYV neutralizing antibodies with activity against related Una virus and chikungunya virus. Inflammatory cytokines and monocyte activation also peaked coincident with viremia, which was well supported by our transcriptomic analysis highlighting enrichment of interferon signaling and other antiviral processes at 2 days post MAYV infection. The rhesus macaque model of MAYV infection recapitulates many of the aspects of human infection and is poised to facilitate the evaluation of novel therapies and vaccines targeting this re-emerging virus.


Asunto(s)
Infecciones por Alphavirus , Alphavirus , Virus Chikungunya , Animales , Ratones , Masculino , Macaca mulatta , Viremia , Ratones Endogámicos C57BL , Anticuerpos Antivirales
2.
Sci Transl Med ; 15(689): eade5795, 2023 03 29.
Artículo en Inglés | MEDLINE | ID: mdl-36989376

RESUMEN

Yellow fever virus (YFV) is a reemerging global health threat, driven by several factors, including increased spread of the mosquito vector and rapid urbanization. Although a prophylactic vaccine exists, vaccine hesitancy, supply deficits, and distribution difficulties leave specific populations at risk of severe YFV disease, as evidenced by recent outbreaks in South America. To establish a treatment for patients with severe YFV infection, we tested 37 YFV-specific monoclonal antibodies isolated from vaccinated humans and identified two capable of potently neutralizing multiple pathogenic primary YFV isolates. Using both hamster and nonhuman primate models of lethal YFV infection, we demonstrate that a single administration of either of these two potently neutralizing antibodies during acute infection fully controlled viremia and prevented severe disease and death in treated animals. Given the potential severity of YFV-induced disease, our results show that these antibodies could be effective in saving lives and fill a much-needed void in managing YFV cases during outbreaks.


Asunto(s)
Vacuna contra la Fiebre Amarilla , Fiebre Amarilla , Cricetinae , Animales , Humanos , Virus de la Fiebre Amarilla , Anticuerpos Neutralizantes/uso terapéutico , Vacuna contra la Fiebre Amarilla/efectos adversos , Fiebre Amarilla/prevención & control , Anticuerpos Antivirales/uso terapéutico , Anticuerpos Monoclonales/uso terapéutico
3.
JAMA Dermatol ; 2021 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-34132739

RESUMEN

IMPORTANCE: Atopic dermatitis (AD) can be negatively affected by Staphylococcus aureus. The skin microbiome of AD is deficient in coagulase-negative Staphylococcus (CoNS) that can kill S aureus. OBJECTIVE: To evaluate if the antimicrobial-producing CoNS (CoNS-AM+) of a patient with AD can be autologously reintroduced to the same patient to inhibit survival of S aureus and improve clinical outcomes. DESIGN, SETTING, AND PARTICIPANTS: This double-blind, vehicle-controlled, single-center randomized clinical trial of 11 adult patients with moderate to severe AD who were randomized to receive either an autologous CoNS-AM+ (n = 5) or the vehicle (n = 6) was conducted between April 2016 and May 2018. The data were analyzed from May 2018 to July 2019. INTERVENTIONS: Autologous CoNS-AM+ was isolated from swabs that were obtained from the nonlesional skin of each patient with AD, expanded by culture, and then reapplied topically to the forearms at a concentration of 107 colony-forming units/g. MAIN OUTCOMES AND MEASURES: The primary end point of this study was to assess S aureus abundance after 1 week of application of autologous CoNS-AM+ on patients with AD by culture-based and DNA-based methods. The secondary end points were to assess the safety and clinical outcomes. RESULTS: Eleven patients (4 men [36.4%] and 7 women [63/6%]) were recruited based on the inclusion criteria. There were no serious adverse events in groups treated with autologous CoNS-AM+ or the vehicle. Staphylococcus aureus colonization on lesional skin at the end of treatment on patients who were treated with autologous CoNS-AM+ (mean of log10 ratio to baseline, -1.702; 95% CI, -2.882 to -0.523) was reduced by 99.2% compared with vehicle treatment (mean of log10 ratio to baseline, 0.671; 95% CI, -0.289 to 1.613; P = .01) and persisted for 4 days after treatment (CoNS-AM+: mean of log10 ratio to baseline, -1.752; 95% CI, -3.051 to -0.453; vehicle: mean of log10 ratio to baseline, -0.003; 95% CI, -1.083 to 1.076; P = .03). Importantly, local Eczema Area And Severity Index scores that were assessed at day 11 on patients who received CoNS-AM+ (mean of percentage change, -48.45; 95% CI, -84.34 to -12.55) were significantly improved compared with vehicle treatment (mean of percentage change, -4.52; 95% CI, -36.25 to 27.22; P = .04). CONCLUSIONS AND RELEVANCE: The data from this randomized clinical trial suggest that bacteriotherapy with an autologous strain of skin commensal bacteria can safely decrease S aureus colonization and improve disease severity. Although larger studies will be needed, this personalized approach for S aureus reduction may provide an alternative treatment for patients with AD beyond antibiotics, immunosuppression, and immunomodulation. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03158012.

5.
Sci Transl Med ; 9(378)2017 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-28228596

RESUMEN

The microbiome can promote or disrupt human health by influencing both adaptive and innate immune functions. We tested whether bacteria that normally reside on human skin participate in host defense by killing Staphylococcus aureus, a pathogen commonly found in patients with atopic dermatitis (AD) and an important factor that exacerbates this disease. High-throughput screening for antimicrobial activity against S. aureus was performed on isolates of coagulase-negative Staphylococcus (CoNS) collected from the skin of healthy and AD subjects. CoNS strains with antimicrobial activity were common on the normal population but rare on AD subjects. A low frequency of strains with antimicrobial activity correlated with colonization by S. aureus The antimicrobial activity was identified as previously unknown antimicrobial peptides (AMPs) produced by CoNS species including Staphylococcus epidermidis and Staphylococcus hominis These AMPs were strain-specific, highly potent, selectively killed S. aureus, and synergized with the human AMP LL-37. Application of these CoNS strains to mice confirmed their defense function in vivo relative to application of nonactive strains. Strikingly, reintroduction of antimicrobial CoNS strains to human subjects with AD decreased colonization by S. aureus These findings show how commensal skin bacteria protect against pathogens and demonstrate how dysbiosis of the skin microbiome can lead to disease.


Asunto(s)
Antiinfecciosos/farmacología , Antiinfecciosos/uso terapéutico , Bacterias/efectos de los fármacos , Dermatitis Atópica/tratamiento farmacológico , Dermatitis Atópica/microbiología , Piel/microbiología , Staphylococcus aureus/efectos de los fármacos , Secuencia de Aminoácidos , Animales , Péptidos Catiónicos Antimicrobianos/química , Péptidos Catiónicos Antimicrobianos/farmacología , Coagulasa/metabolismo , Recuento de Colonia Microbiana , Disbiosis/tratamiento farmacológico , Disbiosis/microbiología , Humanos , Ratones , Microbiota/efectos de los fármacos , Staphylococcus aureus/crecimiento & desarrollo , Sus scrofa
6.
J Invest Dermatol ; 137(1): 46-56, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27498050

RESUMEN

We show that Staphylococcus epidermidis, a commensal bacterium in the human skin microbiome, produces short-chain fatty acids by glycerol fermentation that can induce adipogenesis. Although the antimicrobial and anti-inflammatory activities of short-chain fatty acids have been previously well characterized, little is known about the contribution of short-chain fatty acids to the adipogenic differentiation of adipose-derived stem cells (ADSCs). We show that ADSCs differentiated into adipocytes and accumulated lipids in the cytoplasm when cultured with butyric acid, a principal short-chain fatty acid in the fermentation metabolites of S. epidermidis. Additionally, a co-drug, butyric acid 2-(2-butyryloxyethoxy) ethyl ester (BA-DEG-BA), released active butyric acid when it was intradermally injected into mouse ears and induced ADSC differentiation, characterized by an increased expression of cytoplasmic lipids and perilipin A. The BA-DEG-BA-induced adipogenic differentiation was mediated via peroxisome proliferator-activated receptor gamma. Furthermore, intradermal injection of ADSCs along with BA-DEG-BA into mouse ears markedly enhanced the adipogenic differentiation of ADSCs, leading to dermal augmentation. Our study introduces BA-DEG-BA as an enhancer of ADSC adipogenesis and suggests an integral interaction between the human skin microbiome and ADSCs.


Asunto(s)
Tejido Adiposo/citología , Ácido Butírico/farmacología , Microbiota/efectos de los fármacos , Staphylococcus epidermidis/metabolismo , Células Madre/citología , Adipocitos/citología , Adipocitos/fisiología , Tejido Adiposo/metabolismo , Animales , Diferenciación Celular , Medios de Cultivo Condicionados , Femenino , Humanos , Ratones , Ratones Noqueados , Microbiota/fisiología , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Piel/citología , Piel/microbiología , Staphylococcus epidermidis/efectos de los fármacos
7.
J Invest Dermatol ; 136(11): 2192-2200, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27381887

RESUMEN

Patients with atopic dermatitis (AD) have an abnormal skin barrier and are frequently colonized by S. aureus. In this study we investigated if S. aureus penetrates the epidermal barrier of subjects with AD and sought to understand the mechanism and functional significance of this entry. S. aureus was observed to be more abundant in the dermis of lesional skin from AD patients. Bacterial entry past the epidermis was observed in cultured human skin equivalents and in mice but was found to be increased in the skin of cathelicidin knockout and ovalbumin-sensitized filaggrin mutant mice. S. aureus penetration through the epidermis was dependent on bacterial viability and protease activity, because killed bacteria and a protease-null mutant strain of S. aureus were unable to penetrate. Entry of S. aureus directly correlated with increased expression of IL-4, IL-13, IL-22, thymic stromal lymphopoietin, and other cytokines associated with AD and with decreased expression of cathelicidin. These data illustrate how abnormalities of the epidermal barrier in AD can alter the balance of S. aureus entry into the dermis and provide an explanation for how such dermal dysbiosis results in increased inflammatory cytokines and exacerbation of disease.


Asunto(s)
Anticuerpos Antibacterianos/inmunología , Citocinas/biosíntesis , Dermatitis Atópica/inmunología , Epidermis/metabolismo , Staphylococcus aureus/aislamiento & purificación , Animales , Células Cultivadas , Citocinas/genética , ADN/genética , Dermatitis Atópica/microbiología , Dermatitis Atópica/patología , Epidermis/inmunología , Epidermis/patología , Proteínas Filagrina , Regulación de la Expresión Génica , Humanos , Masculino , Ratones , Ratones Noqueados , Transducción de Señal , Staphylococcus aureus/inmunología
8.
Immunity ; 45(1): 119-30, 2016 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-27438769

RESUMEN

Type 1 interferons (IFNs) promote inflammation in the skin but the mechanisms responsible for inducing these cytokines are not well understood. We found that IFN-ß was abundantly produced by epidermal keratinocytes (KCs) in psoriasis and during wound repair. KC IFN-ß production depended on stimulation of mitochondrial antiviral-signaling protein (MAVS) by the antimicrobial peptide LL37 and double stranded-RNA released from necrotic cells. MAVS activated downstream TBK1 (TANK-Binding Kinase 1)-AKT (AKT serine/threonine kinase 1)-IRF3 (interferon regulatory factor 3) signaling cascade leading to IFN-ß production and then promoted maturation of dendritic cells. In mice, the production of epidermal IFN-ß by LL37 required MAVS, and human wounded and/or psoriatic skin showed activation of MAVS-associated IRF3 and induction of MAVS and IFN-ß gene signatures. These findings show that KCs are an important source of IFN-ß and MAVS is critical to this function, and demonstrates how the epidermis triggers unwanted skin inflammation under disease conditions.


Asunto(s)
Catelicidinas/metabolismo , Células Dendríticas/fisiología , Epidermis/patología , Queratinocitos/inmunología , Mitocondrias/metabolismo , Psoriasis/inmunología , Heridas y Lesiones/inmunología , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Animales , Péptidos Catiónicos Antimicrobianos , Catelicidinas/genética , Diferenciación Celular , Células Cultivadas , Humanos , Interferón beta/metabolismo , Ratones , Ratones Noqueados , ARN Interferente Pequeño/genética , Transducción de Señal , Cicatrización de Heridas
9.
Dermatol Ther (Heidelb) ; 6(3): 379-95, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27363851

RESUMEN

BACKGROUND: Basal cell carcinomas (BCCs) usually occur in sun-exposed areas. However, they may also occur-albeit infrequently-in unusual locations, such as the nipple-areola complex. METHODS: Using the PubMed database, an extensive literature search was performed for the following keywords: areola, basal cell carcinoma, and nipple. Papers and references cited in those papers were reviewed to accumulate reports of patients with BCC of the areola and nipple. RESULTS: BCC of the areola and nipple has been described in 55 individuals: 35 males and 20 females. The onset age ranged from 35 to 86 years. The median onset age in males was 61 years, whereas the median onset age in females was 66 years. BCC of the NAC predominantly occurred in Caucasians (75.7%). BCC of the nipple-areola complex (NAC) was observed on the left (54.9%) more frequently than the right (45.1%). Clinical presentation was variable and commonly included scaly or ulcerated plaques and nodules. This tumor was typically associated with the nodular (42.9%) or superficial (30.9%) subtype of BCC. The most common treatment was excision. There were three reported patients who had metastatic disease to their lymph nodes; one of the patients died from his tumor. CONCLUSION: The nipple and areola are uncommon sites of BCC. BCC of the nipple-areola complex is less frequently observed in females (36.4%), as this is more commonly a photo-protected site. BCC of the NAC has been considered to behave more aggressively than BCCs at other anatomical sites; however, the BCCs are frequently associated with a non-aggressive histologic subtype. Treatment usually involves complete excision of the BCC. Tumor recurrence was uncommon following successful treatment of the primary neoplasm.

10.
J Neuroradiol ; 40(1): 1-10, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23428245

RESUMEN

OBJECTIVES: This was a prospective, cross-sectional study to evaluate the risk factors and symptoms associated with specific carotid wall and atherosclerotic plaque features as seen on computed tomography-angiography (CTA) studies. MATERIALS AND METHODS: A total of 120 consecutive consenting patients admitted to the emergency department with suspected cerebrovascular ischemia, and receiving standard-of-care CTA of the brain and neck on a 64-slice CT scanner, were prospectively enrolled in the study. The carotid wall features observed on CT were quantitatively analyzed with customized software using different radiodensities for contrast-phase acquisition of the carotids. Clinical datasets, including a complete medical history and examination, were obtained by research physicians or specially trained associates blinded to any findings on CT. Univariate and multivariate analyses were performed to assess the degree of association between clinical indicators and quantitative CT features of carotid atherosclerotic plaques. RESULTS: Men tended to have increased carotid lumen (coefficient: 608.7; 95% CI: 356.9-860.6; P<0.001) and wall volumes (209.2; 54.5-364.0; P=0.008), and hypertension was associated with increased wall volume (260.6; 88.7-432.6; P=0.003). Advanced age was associated with increases in maximum wall thickness (0.02; 0.003-0.05; P=0.029), fibrous cap thickness (0.005; 0.001-0.008; P=0.016) and number of calcium voxels (2.7; 1.25-4.2; P<0.001), and the presence of a carotid bruit was associated with carotid stenosis length (21.0; 5.38-37.8; P=0.009). Exercise was inversely related to the number of calcium (-37.1; -71.5 - -2.7; P=0.035) and lipid (-7.9; -15.1 - -0.7; P=0.032) voxels. ACE inhibitor use was associated with fibrous cap thickness (0.1; 0.04-0.23; P=0.005). CONCLUSION: Significant associations were found between clinical descriptors and carotid atherosclerotic plaque features as revealed by CT. Future studies are needed to validate our findings, and to continue investigations into whether CT features of carotid plaques can be used as biomarkers to quantify the impact of strategies aiming to correct vascular risk factors.


Asunto(s)
Angiografía/estadística & datos numéricos , Isquemia Encefálica/diagnóstico por imagen , Isquemia Encefálica/epidemiología , Enfermedades de las Arterias Carótidas/epidemiología , Hipertensión/epidemiología , Tomografía Computarizada por Rayos X/estadística & datos numéricos , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Comorbilidad , Femenino , Humanos , Hipertensión/diagnóstico , Masculino , Persona de Mediana Edad , Prevalencia , Factores de Riesgo , San Francisco/epidemiología , Distribución por Sexo
11.
Genome Med ; 4(2): 14, 2012 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-22360970

RESUMEN

BACKGROUND: Cigarette smoking is well-known to associate with accelerated skin aging as well as cardiovascular disease and lung cancer, in large part due to oxidative stress. Because metabolites are downstream of genetic variation, as well as transcriptional changes and post-translational modifications of proteins, they are the most proximal reporters of disease states or reversal of disease states. METHODS: In this study, we explore the potential effects of commonly available oral supplements (containing antioxidants, vitamins and omega-3 fatty acids) on the metabolomes of smokers (n = 11) compared to non-smokers (n = 17). At baseline and after 12 weeks of supplementation, metabolomic analysis was performed on serum by liquid and gas chromatography with mass spectroscopy (LC-MS and GC-MS). Furthermore, clinical parameters of skin aging, including cutometry as assessed by three dermatologist raters blinded to subjects' age and smoking status, were measured. RESULTS: Long-chain fatty acids, including palmitate and oleate, decreased in smokers by 0.76-fold (P = 0.0045) and 0.72-fold (P = 0.0112), respectively. These changes were not observed in non-smokers. Furthermore, age and smoking status showed increased glow (P = 0.004) and a decrease in fine wrinkling (P = 0.038). Cutometry showed an increase in skin elasticity in smokers (P = 0.049) but not in non-smokers. Complexion analysis software (VISIA) revealed decreases in the number of ultraviolet spots (P = 0.031), and cutometry showed increased elasticity (P = 0.05) in smokers but not non-smokers. CONCLUSIONS: Additional future work may shed light on the specific mechanisms by which long-chain fatty acids can lead to increased glow, improved elasticity measures and decreased fine wrinkling in smokers' skin. Our study provides a novel, medicine-focused application of available metabolomic technology to identify changes in sera of human subjects with oxidative stress, and suggests that oral supplementation (in particular, commonly available antioxidants, vitamins and omega-3 fatty acids) affects these individuals in a way that is unique (compared to non-smokers) on a broad level.

12.
Stroke ; 41(8): 1604-9, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20595672

RESUMEN

BACKGROUND AND PURPOSE: The purpose of this study was to determine whether significant atherosclerotic disease in the carotid arteries predicts significant atherosclerotic disease in the coronary arteries, vertebral arteries, or aorta in patients with symptoms of acute ischemic stroke. METHODS: Atherosclerotic disease was imaged using CT angiography in a prospective study of 120 consecutive patients undergoing emergent CT evaluation for symptoms of stroke. Using a comprehensive CT angiography protocol that captured the carotid arteries, coronary arteries, vertebral arteries, and aorta, we evaluated these arteries for the presence and severity of atherosclerotic disease. Significant atherosclerotic disease was defined as >50% stenosis in the carotid, coronary, and vertebral arteries, or >or=4 mm thickness and encroaching in the aorta. Presence of any and significant atherosclerotic disease was compared in the different types of arteries assessed. RESULTS: Of these 120 patients, 79 had CT angiography examinations of adequate image quality and were evaluated in this study. Of these 79 patients, 33 had significant atherosclerotic disease. In 26 of these 33 patients (79%), significant disease was isolated to 1 type of artery, most often to the coronary arteries (N=14; 54%). Nonsignificant atherosclerotic disease was more systemic and involved multiple arteries. CONCLUSIONS: Significant atherosclerotic disease in the carotid arteries does not predict significant atherosclerotic disease in the coronary arteries, vertebral arteries, or aorta in patients with symptoms of acute ischemic stroke. Significant atherosclerotic disease is most often isolated to 1 type of artery in these patients, whereas nonsignificant atherosclerotic disease tends to be more systemic.


Asunto(s)
Enfermedades de la Aorta/diagnóstico por imagen , Aterosclerosis/diagnóstico por imagen , Isquemia Encefálica/diagnóstico por imagen , Enfermedades de las Arterias Carótidas/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Accidente Cerebrovascular/diagnóstico por imagen , Arteria Vertebral/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Radiografía , Factores de Riesgo
13.
J Neurotrauma ; 27(2): 325-30, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19895192

RESUMEN

The goal of our study was to determine the interobserver variability between observers with different backgrounds and experience when interpreting computed tomography (CT) imaging features of traumatic brain injury (TBI). We retrospectively identified a consecutive series of 50 adult patients admitted at our institution with a suspicion of TBI, and displaying a Glasgow Coma Scale score < or =12. Noncontrast CT (NCT) studies were anonymized and sent to five reviewers with different backgrounds and levels of experience, who independently reviewed each NCT scan. Each reviewer assessed multiple CT imaging features of TBI and assigned every NCT scan a Marshall and a Rotterdam grading score. The interobserver agreement and coefficient of variation were calculated for individual CT imaging features of TBI as well as for the two scores. Our results indicated that the imaging review by both neuroradiologists and neurosurgeons were consistent with each other. The kappa coefficient of agreement for all CT characteristics showed no significant difference in interpretation between the neurosurgeons and neuroradiologists. The average Bland and Altman coefficients of variation for the Marshall and Rotterdam classification systems were 12.7% and 21.9%, respectively, which indicates acceptable agreement among all five reviewers. In conclusion, there is good interobserver reproducibility between neuroradiologists and neurosurgeons in the interpretation of CT imaging features of TBI and calculation of Marshall and Rotterdam scores.


Asunto(s)
Lesiones Encefálicas/diagnóstico por imagen , Lesiones Encefálicas/epidemiología , Variaciones Dependientes del Observador , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Tomografía Computarizada por Rayos X , Adulto Joven
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