RESUMEN
BACKGROUND: Visible light (VL) is known to induce pigmentation in dark-skinned individuals and immediate erythema in light-skinned individuals. However, the effects of accumulated low-dose VL exposure across skin types are not well established. METHODS: Thirty-one healthy subjects with light (Fitzpatrick skin types [FST] I-II, n = 13) and dark (FST V-VI, n = 18) skin types were enrolled. Subjects' buttocks were exposed daily to VL, wavelength 400-700 nm, with a dose of 120 J/cm2 at 50 mW/cm2 , for four consecutive days. Microarray using Affymetrix GeneChip (49,395 genes) was performed followed by qRT-PCR on skin samples. RESULTS: Repeated low-dose VL irradiation induced immediate pigment darkening and delayed tanning in dark-skinned individuals while no discernable pigmentation and erythema were observed in light-skinned individuals. Top ten upregulated genes by repeated VL exposure in microarray included melanogenic genes such as tyrosinase (TYR), tyrosinase-related protein-1 (TYRP1), dopachrome tautomerase (DCT), premelanosome protein (PMEL), melan-A (MLANA), and solute carrier family 24, member 5 (SLC24A5) and genes involved in inflammation/matrix remodeling/cell signaling including chemokine (C-C motif) ligand 18 (CCL18), BCL2-related protein A1 (BCL2A1), and cartilage oligomeric matrix protein (COMP). In qRT-PCR CCL18 was upregulated in light skin with a greater extent (mean fold change ± SD; 4.03 ± 3.28, p = .04) than in dark-skinned individuals (1.91 ± 1.32, p = .07) while TYR was not significantly upregulated in both skin types. CONCLUSION: This study highlights the genes upregulated by cumulative VL exposure involved in pigmentation, immune response, oxidation/reduction, and matrix remodeling across skin types providing relevant information on daily solar exposure.
Asunto(s)
Pigmentación de la Piel , Rayos Ultravioleta , Humanos , Luz , Piel/efectos de la radiación , EritemaRESUMEN
BACKGROUND: Several inflammatory cytokines are upregulated in severe coronavirus disease 2019 (COVID-19). We compared cytokines in COVID-19 versus influenza to define differentiating features of the inflammatory response to these pathogens and their association with severe disease. Because elevated body mass index (BMI) is a known risk factor for severe COVID-19, we examined the relationship of BMI to cytokines associated with severe disease. METHODS: Thirty-seven cytokines and chemokines were measured in plasma from 135 patients with COVID-19, 57 patients with influenza, and 30 healthy controls. Controlling for BMI, age, and sex, differences in cytokines between groups were determined by linear regression and random forest prediction was used to determine the cytokines most important in distinguishing severe COVID-19 and influenza. Mediation analysis was used to identify cytokines that mediate the effect of BMI and age on disease severity. RESULTS: Interleukin-18 (IL-18), IL-1ß, IL-6, and tumor necrosis factor-α (TNF-α) were significantly increased in COVID-19 versus influenza patients, whereas granulocyte macrophage colony-stimulating factor, interferon-γ (IFN-γ), IFN-λ1, IL-10, IL-15, and monocyte chemoattractant protein 2 were significantly elevated in the influenza group. In subgroup analysis based on disease severity, IL-18, IL-6, and TNF-α were elevated in severe COVID-19, but not in severe influenza. Random forest analysis identified high IL-6 and low IFN-λ1 levels as the most distinct between severe COVID-19 and severe influenza. Finally, IL-1RA was identified as a potential mediator of the effects of BMI on COVID-19 severity. CONCLUSIONS: These findings point to activation of fundamentally different innate immune pathways in severe acute respiratory syndrome coronavirus 2 and influenza infection, and emphasize drivers of severe COVID-19 to focus both mechanistic and therapeutic investigations.
Asunto(s)
COVID-19 , Gripe Humana , Quimiocinas , Citocinas , Humanos , SARS-CoV-2RESUMEN
OBJECTIVES: We designed this study to test whether clazakizumab, a direct interleukin-6 inhibitor, benefits patients hospitalized with severe or critical COVID-19 disease accompanied by hyperinflammation. DESIGN: Multicenter, randomized, double-blinded, placebo-controlled, seamless phase II/III trial. SETTING: Five U.S. medical centers. PATIENTS: Adults inpatients with severe COVID-19 disease and hyperinflammation. INTERVENTIONS: Eighty-one patients enrolled in phase II, randomized 1:1:1 to low-dose (12.5 mg) or high-dose (25 mg) clazakizumab or placebo. Ninety-seven patients enrolled in phase III, randomized 1:1 to high-dose clazakizumab or placebo. MEASUREMENTS AND MAIN RESULTS: The primary outcome was 28-day ventilator-free survival. Secondary outcomes included overall survival, frequency and duration of intubation, and frequency and duration of ICU admission. Per Data Safety and Monitoring Board recommendations, additional secondary outcomes describing clinical status and status changes, as measured by an ordinal scale, were added. Bayesian cumulative proportional odds, logistic, and Poisson regression models were used. The low-dose arm was dropped when the phase II study suggested superiority of the high-dose arm. We report on 152 patients, 74 randomized to placebo and 78 to high-dose clazakizumab. Patients receiving clazakizumab had greater odds of 28-day ventilator-free survival (odds ratio [OR] = 3.84; p [OR > 1] 99.9%), as well as overall survival at 28 and 60 days (OR = 1.75; p [OR > 1] 86.5% and OR = 2.53; p [OR > 1] 97.7%). Clazakizumab was associated with lower odds of intubation (OR = 0.2; p [OR] < 1; 99.9%) and ICU admission (OR = 0.26; p [OR < 1] 99.6%); shorter durations of ventilation and ICU stay (risk ratio [RR] < 0.75; p [RR < 1] > 99% for both); and greater odds of improved clinical status at 14, 28, and 60 days (OR = 2.32, p [OR > 1] 98.1%; OR = 3.36, p [OR > 1] 99.6%; and OR = 3.52, p [OR > 1] 99.8%, respectively). CONCLUSIONS: Clazakizumab significantly improved 28-day ventilator-free survival, 28- and 60-day overall survival, as well as clinical outcomes in hospitalized patients with COVID-19 and hyperinflammation.
Asunto(s)
Anticuerpos Monoclonales Humanizados , Tratamiento Farmacológico de COVID-19 , COVID-19 , Adulto , Anticuerpos Monoclonales Humanizados/uso terapéutico , Teorema de Bayes , COVID-19/complicaciones , Método Doble Ciego , Humanos , SARS-CoV-2 , Resultado del TratamientoRESUMEN
Rosacea is a chronic, often progressive disorder characterized by facial erythema, telangiectasias, papules, pustules, and/or rhinophyma. In this study, we investigated the tissue structure in rosacea compared to controls. We performed a case-control study between five patients with mild-to-moderate erythematotelangiectatic rosacea (ETR) and five matched controls. Facial biopsy samples from rosacea patients and controls were stained with picrosirius red for collagen and CD31 for microvessel identification. Mean collagen content was significantly greater in control samples (19.603% ±8.821%) compared to rosacea samples (16.812% ± 7.787%, p = 0.030). In contrast, mean microvessel density was significantly higher in rosacea patients (4.775 E-5 ± 1.493 E-5 µm-3 ) compared to controls (2.559 E-5 ± 8.732 E-6 µm-3 , p = 0.004). Mean microvessel lumen area was also significantly higher in rosacea patients (491.710 ± 610.188 µm2 ) compared to controls (347.879 ± 539.624 µm2 , p = 0.003). We identified a correlation between decreased collagen content and increased microvessel size and density in rosacea patients that was not observed in controls. These structural changes to the dermal matrix may contribute to the characteristic vessel growth and dilation in rosacea.
Asunto(s)
Colágeno/metabolismo , Cara/patología , Rosácea/patología , Envejecimiento de la Piel/patología , Piel/patología , Telangiectasia/patología , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Eritema/metabolismo , Eritema/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Rosácea/metabolismo , Piel/metabolismo , Telangiectasia/metabolismoRESUMEN
Sphingolipids constitute a significant fraction of cellular plasma membrane lipid content. Among sphingolipids, ceramide levels are usually very low. However, in some cell processes like apoptosis, cell membrane ceramide levels increase markedly because of the activation of enzymes like acid sphingomyelinase. This increase can change the physical state of the membrane by promoting molecular order and inducing solid-ordered (So) phase domains. This effect has been observed in a previous 2H NMR study on membranes consisting of palmitoyl sphingomyelin (PSM) and palmitoyl ceramide (PCer). Cholesterol (Chol), too, is present at high concentrations in mammalian plasma membranes and has a favorable interaction with sphingomyelin (SM), together forming domains in the liquid-ordered phase in model membranes. There are reports that Chol is able to displace ceramide (Cer) in SM bilayers and abolish the So phase domains formed by SM:Cer. This ability of Chol appears to be concentration dependent; in membranes with low Chol and high Cer contents, So phase domains rich in Cer coexist with the continuous fluid phase of the membrane. Here, we studied the effect of increasing PCer concentration in PSM:Chol bilayers, using 2H NMR. Chol:PCer mole ratios were 3:1, 3:2, and 3:3, at a fixed 7:3 phospholipid:cholesterol mol ratio. Both PSM and PCer were monitored in separate samples for changes in their physical state by introducing a perdeuterated palmitoyl chain in either molecule. Moreover, the effect of replacing PSM with DPPC was investigated to test the impact on membrane phase behavior of replacing the sphingosine with a palmitoylated glycerol backbone. We found that PCer can increase acyl chain order in both PSM:Chol and DPPC:Chol bilayers. Especially in bilayers with Chol:PCer 1:1 molar ratios, PCer induces highly stable So phase domains in both PSM and DPPC bilayers near 37°C. However, PCer has a more pronounced ordering effect on PSM compared to DPPC bilayers.
Asunto(s)
Ceramidas/química , Colesterol/química , Deuterio/química , Espectroscopía de Resonancia Magnética , Fosfolípidos/química , TemperaturaRESUMEN
In this paper we investigate the pseudo-ternary phase diagram of glycerol monooleate (GMO), a cationic lipid (DOTAP - 1,2-dioleoyl-3-trimethylammonium propane), and a "PEGylated" lipid (DOPE-PEG - 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethylene glycol)-2000 kDa]) in excess water. We use small angle X-ray scattering (SAXS) and cryogenic transmission electron microscopy (Cryo-EM) to map out a phase diagram in a regime of low DOPE-PEG content (1-5 mol%), which is pertinent for the application of lipid systems as carriers of biomolecular cargo to cells. Pure GMO is known to self-assemble into bicontinuous cubic phases of the gyroid type at low water content and of the diamond type in excess water. These complex structures have numerous advantages reaching beyond drug delivery, e.g. as protein crystallization matrices, but their formulation is challenging as very small contents of guest molecules can shift the phase behavior towards other geometries such as the lamellar phase. In this work, we show that the ternary GMO/DOTAP/DOPE-PEG system allows the stabilization of bicontinuous cubic phases in excess water over a wide composition range. The symmetry of the phase can be tuned by varying the amount of PEGylated lipid, with the primitive type dominating at low DOPE-PEG content (1-3 mol%) and the diamond phase arising at 5 mol% DOPE-PEG. In addition, we found that the diamond phase is virtually non-responsive to electrostatic swelling. In contrast, primitive bicontinuous cubic lattice dimensions swell up in equilibrium to 650 Å with increased cationic lipid content.
RESUMEN
The hierarchical assembly of lipids, as modulated by composition and environment, plays a significant role in the function of biological membranes and a myriad of diseases. Elevated concentrations of calcium ions and cardiolipin (CL), an anionic tetra-alkyl lipid found in mitochondria and some bacterial cell membranes, have been implicated in pneumonia recently. However, their impact on the physicochemical properties of lipid assemblies in lungs and how it impairs alveoli function is still unknown. We use small- and wide-angle X-ray scattering (S/WAXS) and solid-state nuclear magnetic resonance (ssNMR) to probe the structure and dynamics of lung-mimetic multilamellar bodies (MLBs) in the presence of Ca2+ and CL. We conjecture that CL overexpressed in the hypophase of alveoli strongly affects the structure of lung-lipid bilayers and their stacking in the MLBs. Specifically, S/WAXS data revealed that CL induces significant shrinkage of the water-layer separating the concentric bilayers in multilamellar aggregates. ssNMR measurements indicate that this interbilayer tightening is due to undulation repulsion damping as CL renders the glycerol backbone of the membranes significantly more static. In addition to MLB dehydration, CL promotes intrabilayer phase separation into saturated-rich and unsaturated-rich lipid domains that couple across multiple layers. Expectedly, addition of Ca2+ screens the electrostatic repulsion between negatively charged lung membranes. However, when CL is present, addition of Ca2+ results in an apparent interbilayer expansion likely due to local structural defects. Combining S/WAXS and ssNMR on systems with compositions pertinent to healthy and unhealthy lung membranes, we propose how alteration of the physiochemical properties of MLBs can critically impact the breathing cycle.
Asunto(s)
Membrana Celular/química , Membrana Celular/efectos de los fármacos , Neumonía/fisiopatología , Calcio/farmacología , Cardiolipinas/farmacología , Humanos , Membrana Dobles de Lípidos/química , Pulmón/efectos de los fármacos , Espectroscopía de Resonancia Magnética , Dispersión de Radiación , Rayos XRESUMEN
BACKGROUND: Increased photoprotection by natural melanin allows for African-Americans to be less impacted by photoaging than Caucasians. However, less is known about chronological aging in this population. OBJECTIVE: To create a photonumeric scale for African-Americans to evaluate chronological skin aging and to explore contributing elements to intrinsic aging. METHODS: Standardized photographs of the upper inner arm were taken from 75 African-American participants. Five participants were chosen as standards to create a 9-point photonumeric scale (0 = none, 8 = most severe). The scale was utilized by three blinded dermatologists to independently rate participants' photographs. RESULTS: The interrater agreements were 0.768 (95% CI: 0.671-0.834) for trial 1 and 0.725 (0.608-0.794) for trial 2. The intrarater agreements were 0.757 (0.596-0.875), 0.850 (0.771-0.903), and 0.790 (0.686-0.855) for the three raters. Averaged chronological aging scores were correlated with participants' survey responses, which revealed age as a significant predictor (r = 0.72, p < 0.001). LIMITATION: Our study was limited by the sample size, although the number of study participants was similar on a investigation in Caucasians. CONCLUSION: This study created the first reliable photonumeric scale for chronologic skin aging in African-Americans and found increased age and greater BMI as contributors to intrinsic skin aging phenotype in this population.
Asunto(s)
Envejecimiento/fisiología , Negro o Afroamericano , Envejecimiento de la Piel , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Brazo , Índice de Masa Corporal , Femenino , Humanos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Fotograbar , Adulto JovenRESUMEN
BACKGROUND: African-Americans are less affected by photoaging than lighter skin individuals. Although scales for photoaging have been developed for Caucasians and Asians, no scale exists for African-Americans. AIM: To develop a photonumeric scale for photoaging and to determine factors that contribute to photoaging in African-Americans. METHODS: Five participants' photographs were selected as standards to create a 9-point photonumeric scale (0 = none, 8 = most severe). Three blinded dermatologists used the scale to grade the remaining participants' photographs. RESULTS: Interrater reliabilities were 0.775 (95% CI: 0.635, 0.880) for trial 1 and 0.832 (0.747, 0.883) for trial 2. Intrarater reliabilities, assessed over a 1 week interval, were 0.863 (0.727, 0.940), 0.928 (0.890, 0.954), and 0.866 (0.739, 0.935) for the three graders, indicating strong agreement. Photoaging scores were then correlated with participants' survey on lifestyle factors, which yielded age as a significant predictor (r = 0.91, p < 0.001). Furthermore, multiple regression model to predict facial photoaging (adjusted R2 = 0.849) selected age (b1 = 0.111, p < 0.001), sun exposure (b2 = 0.206, p = 0.014), and gender (b2 = -0.388, p = 0.063) as the most important variables. CONCLUSIONS: A reliable photonumeric scale for photoaging in African Americans was developed. Age, sun exposure, and male gender were found to be contributory factors to photoaging.
Asunto(s)
Negro o Afroamericano , Envejecimiento de la Piel/etnología , Luz Solar/efectos adversos , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Cara , Femenino , Humanos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Fotograbar , Factores Sexuales , Método Simple Ciego , Encuestas y Cuestionarios , Adulto JovenRESUMEN
BACKGROUND: Tristimulus colorimetry, which uses the Commission Internationale de l'Eclairage L*a*b* model to quantify color, has previously been used to analyze pigmentation and erythema in human skin; however, colorimetry of African American skin is not well characterized. OBJECTIVE: We sought to analyze skin color patterns in African Americans and compare them with those of Caucasians. METHODS: Colorimetry readings of the sun-protected buttock and sun-exposed back of forearm were taken from 40 Caucasian and 43 African American participants from March 2011 through August 2015. African American participants also completed a lifestyle questionnaire. Correlation coefficients, paired t tests, and multivariable linear regression analyses were used for statistical comparisons. RESULTS: Forearm skin was lighter in African Americans ages 65 years and older versus 18 to 30 years (P = .02) but darker in Caucasians ages 65 years or older versus 18 to 30 years (P = .03). In African Americans ages 18 to 30 years, the buttock was darker than the forearm (P < .001), whereas in Caucasians the buttock was lighter than the forearm (P < .001). A lighter forearm than buttock was correlated with supplement use, smoking (ages 18-30 years), and less recreational sun exposure (ages ≥65 years) in African Americans. LIMITATIONS: Our study was limited by the sample size and focal geographic source. CONCLUSIONS: Pigmentation patterns regarding sun-protected and sun-exposed areas in African Americans may differ from that of Caucasians, suggesting that other factors may contribute to skin pigmentation in African Americans.
Asunto(s)
Negro o Afroamericano/estadística & datos numéricos , Hipopigmentación/fisiopatología , Pigmentación/fisiología , Envejecimiento de la Piel/fisiología , Población Blanca/estadística & datos numéricos , Adulto , Factores de Edad , Anciano , Envejecimiento/fisiología , Estudios de Cohortes , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Medición de Riesgo , Adulto JovenRESUMEN
BACKGROUND: The shave biopsy using a razor with an open blade is the current standard of care for sampling superficial skin lesions. OBJECTIVE: To enhance safety, the authors developed a novel biopsy device with a closed blade design for removing the epidermal layer of skin and evaluated against the open razor blade for tolerability, scarring, and accuracy in histological diagnosis. MATERIALS AND METHODS: Shave biopsies were performed using the novel device or razor blade on benign epidermal skin lesions in 10 patients on comparable body parts. Digital photography, colorimetry, scar scale evaluations, and questionnaires were used to evaluate the efficacy and tolerability of the devices. RESULTS: For all patients, accurate histological diagnoses were made regardless of device type. No statistically significant differences were detected between the novel device and razor blade in terms of scar scale assessments, colorimetry, and questionnaire responses. Both patients and the participating dermatologist reported satisfaction with the safety and performance of the novel device. No injuries to the provider occurred with either instrument. CONCLUSION: The rotating sphere biopsy device is a potential alternative to the razor blade with comparable tolerability, scarring, and accuracy in histological diagnoses, offering improved safety for patients and health care providers.
Asunto(s)
Biopsia/instrumentación , Hemangioma/patología , Nevo/patología , Neoplasias Cutáneas/patología , Piel/patología , Anciano , Anciano de 80 o más Años , Actitud del Personal de Salud , Biopsia/efectos adversos , Cicatriz/etiología , Cicatriz/patología , Colorimetría , Femenino , Estudios de Seguimiento , Humanos , Queratosis Seborreica/patología , Masculino , Persona de Mediana Edad , Satisfacción del Paciente , Fotograbar , Encuestas y CuestionariosRESUMEN
Ceramide produced from sphingomyelin in the plasma membrane is purported to affect signaling through changes in the membrane's physical properties. Thermal behavior of N-palmitoyl sphingomyelin (PSM) and N-palmitoyl ceramide (PCer) mixtures in excess water has been monitored by ²H NMR spectroscopy and compared to differential scanning calorimetry (DSC) data. The alternate use of either perdeuterated or proton-based N-acyl chain PSM and PCer in our ²H NMR studies has allowed the separate observation of gel-fluid transitions in each lipid in the presence of the other one, and this in turn has provided direct information on the lipids' miscibility over a wide temperature range. The results provide further evidence of the stabilization of the PSM gel state by PCer. Moreover, overlapping NMR and DSC data reveal that the DSC-signals parallel the melting of the major component (PSM) except at intermediate (20 and 30 mol %) fractions of PCer. In such cases, the DSC endotherm reports on the presumably highly cooperative melting of PCer. Up to at least 50 mol % PCer, PSM and PCer mix ideally in the liquid crystalline phase; in the gel phase, PCer becomes incorporated into PSM:PCer membranes with no evidence of pure solid PCer.
Asunto(s)
Ceramidas/química , Transición de Fase , Esfingomielinas/química , Colesterol/química , Cristales Líquidos/química , TemperaturaRESUMEN
Importance: Topical formulations of tretinoin precursors (retinol and its ester derivatives) are widely available over the counter and may offer similar clinical benefits to those of tretinoin for treatment of photoaging. However, which of the many purported molecular effects of retinoids most strongly drives clinical improvements in tretinoin-treated skin remains unclear. Objectives: To evaluate the clinical efficacy of topical tretinoin precursors (TTP) vs tretinoin (RA) in treating moderate to severe facial photodamage and to identify potential biomarkers that correlate with clinical efficacy. Design, Setting, and Participants: This randomized, double-blind, single-center, parallel-arm study of 24 patients with moderate to severe facial photodamage was conducted at an academic referral center from November 2010 to December 2011, with data analysis performed from January 2012 to December 2021. Interventions: Daily topical application of 0.02% RA or 1.1% TTP formulation containing retinol, retinyl acetate, and retinyl palmitate for 24 weeks. Main Outcomes and Measures: Photoaging and tolerability were assessed by dermatologist evaluations and patient-reported outcomes. Target gene expression was assessed by real-time quantitative polymerase chain reaction of biopsied tissue from treated areas. Results: A total of 20 White women were ultimately analyzed (9 randomized to TTP, 11 randomized to RA). At week 24, there was no significant difference in Griffiths photoaging scores among patients receiving TTP vs RA (median, 4 vs 5) (TTP - RA difference: -1; 95% CI, -2 to 1; P = .27). Treatment with TTP was associated with erythema 6 times less frequently than RA (11% vs 64%) (TTP - RA difference: -0.53; 95% CI, -0.88 to -0.17; P = .01). Target gene analysis showed significant CRABP2 messenger RNA (mRNA) induction (confirming retinoic acid receptor signaling) but no significant changes in procollagen I or MMP1/3/9 mRNA in TTP-treated samples. Instead, MMP2 mRNA, which encodes a type IV collagenase, was significantly reduced in TTP-treated samples (week 24 - baseline mRNA difference: -5; 96% CI, -33 to 1.6; P = .02), and changes in MMP2 were strongly correlated with changes in fine wrinkles (r = 0.54; 95% CI, 0.12 to 0.80; P = .01). Interestingly, patients with severe baseline wrinkles exhibited greater improvements (r = -0.74; 95% CI, -0.89 to -0.43; P < .001). This trend was mirrored in MMP2 mRNA, with initial expression strongly predicting subsequent changes (r = -0.78; 95% CI, -0.89 to -0.43; P < .001). Conclusions and Relevance: In this randomized clinical trial, there was no significant difference in efficacy between this particular formulation of TTP and tretinoin 0.02%. However, the results of these mechanistic studies highlight MMP2 as a possible mediator of retinoid efficacy in photoaging. Trial Registration: ClinicalTrials.gov Identifier: NCT01283464.
Asunto(s)
Envejecimiento de la Piel , Tretinoina , Biomarcadores , Método Doble Ciego , Femenino , Humanos , Hiperplasia/tratamiento farmacológico , Metaloproteinasa 2 de la Matriz , ARN Mensajero , Retinoides , Piel/efectos de los fármacos , Envejecimiento de la Piel/efectos de los fármacos , Resultado del Tratamiento , Tretinoina/uso terapéutico , Vitamina A/uso terapéuticoRESUMEN
BACKGROUND: The ability of Cutibacterium acnes strains to form biofilms has been correlated with their virulence. OBJECTIVE: This study examined biofilm and skin microbiota in acne patients in order to understand their role in the development of acne lesions. METHODS: Thin sections of punch biopsy specimens of (i) uninflamed comedones, (ii) inflammatory lesions, and (iii) uninvolved adjacent skin of acne patients were examined. Epiflourescence and confocal laser scanning microscopy were used for biofilm detection, and pyrosequencing with taxonomic classification of 16s rRNA gene amplicons was used for microbiota analysis. RESULTS: Of the 39 skin specimens from patients with mild-moderate acne (n = 13) that were studied, nine (23%) contained biofilm. Among these specimens, biofilm was most frequently detected in comedones (55.6%) and less frequently in inflammatory papules (22.2%) and uninvolved skin (22.2%). Comedones demonstrated the highest mean alpha diversity of all the lesion subtypes. The relative abundance of Staphylococcus was significantly higher in comedones (11.400% ± 12.242%) compared to uninvolved skin (0.073% ± 0.185%, P = 0.024). CONCLUSIONS: The microenvironment of the comedone differs from that of inflammatory lesions and unaffected skin. The increased frequency of biofilm in comedones may account for the lack of host inflammatory response to these lesions.
Asunto(s)
Acné Vulgar , Microbiota , Biopelículas , Humanos , Propionibacterium acnes , ARN Ribosómico 16S/genéticaRESUMEN
OBJECTIVE: This open-label 12-week study was conducted to evaluate the efficacy and safety of tofacitinib, a JAK inhibitor, in treatment-refractory active dermatomyositis (DM). METHODS: Tofacitinib in extended-release doses of 11 mg was administered daily to 10 subjects with DM. Prior to treatment, a complete washout of all steroid-sparing agents was performed. The primary outcome measure was assessment of disease activity improvement based on the International Myositis Assessment and Clinical Studies group definition of improvement. Response rate was measured as the total improvement score according to the 2016 American College of Rheumatology (ACR)/European League Against Rheumatism (EULAR) myositis response criteria. Secondary outcome measures included Cutaneous Dermatomyositis Disease Area and Severity Index (CDASI) scores, chemokine levels, immunohistochemical analysis of STAT1 expression in the skin, RNA sequencing analysis, and safety. RESULTS: At 12 weeks, the primary outcome was met in all 10 subjects. Five (50%) of 10 subjects experienced moderate improvement in disease activity, and the other 50% experienced minimal improvement according to the 2016 ACR/EULAR myositis response criteria. The secondary outcome of the mean change in the CDASI activity score over 12 weeks was statistically significant (mean ± SD 28 ± 15.4 at baseline versus 9.5 ± 8.5 at 12 weeks) (P = 0.0005). Serum chemokine levels of CXCL9/CXCL10 showed a statistically significant change from baseline. A marked decrease in STAT1 signaling in association with suppression of interferon target gene expression was demonstrated in 3 of 9 skin biopsy samples from subjects with dermatomyositis. The mean ± SD level of creatine kinase in the 10 subjects at baseline was 82 ± 34.8 IU/liter, highlighting that disease activity was predominantly located in the skin. CONCLUSION: This is the first prospective, open-label clinical trial of tofacitinib in DM that demonstrates strong clinical efficacy of a pan-JAK inhibitor, as measured by validated myositis response criteria. Future randomized controlled trials using JAK inhibitors should be considered for treating DM.
Asunto(s)
Dermatomiositis/tratamiento farmacológico , Inhibidores de las Cinasas Janus/uso terapéutico , Piperidinas/uso terapéutico , Pirimidinas/uso terapéutico , Adulto , Quimiocina CXCL10/metabolismo , Quimiocina CXCL9/metabolismo , Dermatomiositis/metabolismo , Dermatomiositis/fisiopatología , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Músculo Esquelético/metabolismo , Proyectos Piloto , Prueba de Estudio Conceptual , Estudios Prospectivos , RNA-Seq , Factor de Transcripción STAT1/metabolismo , Piel/metabolismo , Resultado del TratamientoRESUMEN
Over the past few decades, the role of self-views in life satisfaction has been extensively investigated. Recently, growing attention has been directed to the question of whether an optimistic worldview, termed "reward for application", helps boost life satisfaction. Conceptually, the association between reward for application and life satisfaction can be paradoxical. Due to various methodological and theoretical shortfalls, previous investigations were unable to draw a robust conclusion on this association. To address these shortfalls, two cross-lagged panel studies were conducted with different time lags. Over and above the potential confounds of self-views (namely, self-esteem and self-rated personality traits), reward for application had a positive effect on lagged life satisfaction among both adolescents and young adults, while the reverse effect was not found. Moreover, we found support for the multiplicative effect between worldviews and self-views, in which the positive effect of reward for application on life satisfaction was attenuated by high self-esteem.
Asunto(s)
Satisfacción Personal , Autoimagen , Adolescente , Humanos , Recompensa , Adulto JovenRESUMEN
Two dimensional phase separation in lipid membranes and cell membranes is of interest to biology because of the idea of membrane rafts - compositionally heterogeneous liquid crystal domains with cellular functions. Few quantitative tools exist for characterizing and differentiating coexisting phases on a molecular scale. Lipid acyl chain order can be measured directly using deuterium nuclear magnetic resonance spectroscopy (2H NMR), or inferred using fluorescence microscopy along with the environment-sensitive probe Laurdan. We found a linear relationship between the 2H NMR order parameter and Laurdan generalized polarization. This observed correlation supports the idea that lipid chain order is tightly associated with the amount and dynamics of water molecules at the glycerol backbone level of the membrane.
Asunto(s)
Membrana Celular/química , Lípidos de la Membrana/química , Resonancia Magnética Nuclear Biomolecular/métodos , 2-Naftilamina/análogos & derivados , 2-Naftilamina/química , Deuterio/química , Polarización de Fluorescencia , Colorantes Fluorescentes/química , Lauratos/química , Microdominios de Membrana/química , Microscopía FluorescenteRESUMEN
Importance: Given the widespread use of systemic antibiotics for treatment of moderate to severe acne, it is important to understand the associations of such antibiotic use with changes not only in Cutibacterium acnes (formerly Propionibacterium acnes) but also in the complete bacterial community of the skin. Objective: To examine the composition, diversity, and resilience of skin microbiota associated with systemic antibiotic perturbation in individuals with acne. Design, Setting, and Participants: This longitudinal cohort study conducted at an academic referral center in Maryland from February 11 to September 23, 2014, included 4 female participants who had received a recent diagnosis of acne vulgaris, showed comedonal and inflammatory acne on the face, were at least 18 years old, and had no recent use of systemic or topical treatments for acne, including antibiotics and retinoids. Data analysis was performed between July 5, 2017, and November 7, 2018. Interventions: Participants were prescribed oral minocycline, 100 mg, twice daily for 4 weeks. Skin areas on the forehead, cheek, and chin were sampled for 16S ribosomal RNA gene sequencing at baseline, 4 weeks after starting minocycline treatment, and then 1 week and 8 weeks after discontinuation of treatment. Main Outcomes and Measures: Skin microbiota examined with respect to relative abundance of bacterial taxa, α diversity (represents within-sample microbial diversity), and ß diversity (represents between-sample microbial diversity). Acne status evaluated with photography and lesion count. Results: Of the 4 patients included in this study, 2 were 25 years old, 1 was 29 years old, and 1 was 35 years old; 2 were white women, 1 was an African American woman, and 1 was an Asian woman. Across all 4 patients, antibiotic treatment was associated with a 1.4-fold reduction in the level of C acnes (difference, -10.3%; 95% CI, -19.9% to -0.7%; P = .04) with recovery following cessation of treatment. Distinct patterns of change were identified in multiple bacterial genera, including a transient 5.6-fold increase in the relative abundance of Pseudomonas species (difference, 2.2%; 95% CI, 0.9%-3.4%; P < .001) immediately following antibiotic treatment, as well as a persistent 1.7-fold increase in the relative abundance of Streptococcus species (difference, 5.4%; 95% CI, 0.3%-10.6%; P = .04) and a 4.7-fold decrease in the relative abundance of Lactobacillus species (difference, -0.8%; 95% CI, -1.4% to -0.2%; P = .02) 8 weeks following antibiotic treatment withdrawal. In general, antibiotic administration was associated with an initial decrease from baseline of bacterial diversity followed by recovery. Principal coordinates analysis results showed moderate clustering of samples by patient (analysis of similarity, R = 0.424; P = .001) and significant clustering of samples by time in one participant (analysis of similarity, R = 0.733; P = .001). Conclusions and Relevance: In this study, systemic antibiotic treatment of acne was associated with changes in the composition and diversity of skin microbiota, with variable rates of recovery across individual patients and parallel changes in specific bacterial populations. Understanding the association between systemic antibiotic use and skin microbiota may help clinicians decrease the likelihood of skin comorbidities related to microbial dysbiosis.
Asunto(s)
Acné Vulgar/tratamiento farmacológico , Antibacterianos/administración & dosificación , Minociclina/administración & dosificación , Piel/patología , Acné Vulgar/microbiología , Acné Vulgar/patología , Administración Oral , Adulto , Bacterias/aislamiento & purificación , Estudios de Cohortes , Femenino , Humanos , Estudios Longitudinales , Microbiota , Proyectos Piloto , Propionibacterium acnes/aislamiento & purificación , Piel/microbiología , Resultado del TratamientoRESUMEN
INTRODUCTION: Scarring is an unfortunate clinical outcome of acne. Current treatment options for atrophic acne scars are dominated by non-pharmacological, invasive procedures which may not be suitable or affordable to all patients. This phase II, single-center, open-label, exploratory study assessed the efficacy, safety and subject-reported outcomes of adapalene 0.3% gel in the treatment of atrophic acne scars. METHODS: The study included subjects aged 18-50 years with past history of acne and moderate to severe facial atrophic acne scars. Subjects received adapalene 0.3% gel once daily for the first 4 weeks and twice daily for the following 20 weeks. Assessments were performed at baseline, day 10 and weeks 4, 8, 16 and 24, and at post-treatment follow-ups (weeks 36 and 48-72). RESULTS: At week 24, investigator and subject assessments reported improvement in skin texture/atrophic scars in 50% and > 80% of subjects, respectively. Subjects were satisfied with the treatment and reported improvements in quality of life. CONCLUSION: Daily use of adapalene 0.3% gel for the treatment of atrophic acne scars showed promising clinical efficacy, a favorable tolerability profile, and improvement in quality of life. FUNDING: Nestlé Skin Health-Galderma R&D. TRIAL REGISTRATION: ClinicalTrials.gov Identifier NCT01213199.