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1.
Phys Chem Chem Phys ; 26(15): 11208-11216, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38564180

RESUMEN

Ammonia is a valuable feedstock for most chemicals, pharmaceuticals, and fertilizer products. It is a promising carbon-free energy source. Under severe experimental circumstances (high temperature and high pressure), ammonia is manufactured industrially using the standard Haber-Bosch process. This process uses a lot of energy and emits a huge amount of CO2 into the environment. One method that is seen to be promising and could eventually replace the Haber-Bosch process is the electrocatalytic production of ammonia. However, in ambient conditions, the cleavage of the nitrogen molecule is exceedingly difficult. As a result, the yield of ammonia remains modest and the study's scope is still restricted to the lab. When the catalytic performance is significantly increased, nitrate and nitrite contaminations in water systems can be effectively removed and simultaneously transformed into energy sources if nitrites or nitrates are employed as nitrogen sources instead of nitrogen gas. This may become a new substitute for the synthesis of ammonia, but nitrate and nitrite reduction are not getting enough attention. In this review, we discuss the performance of the electrocatalytic nitrate reduction reaction, which includes cycling stability, reactivity, selectivity, and faradaic efficiency. Following this summary, we look into the crucial elements, the rate-determining step, and the reaction mechanisms that govern the performance of the nitrate reduction reaction. In order to support the practical use of the electrocatalytic nitrate reduction reaction, we finally provided a summary of the challenges and future directions guiding the design of efficient catalyst and reaction systems.

2.
Mol Divers ; 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38470555

RESUMEN

Globally, lung cancer is a significant public health concern due to its role as the leading cause of cancer-related mortalities. The promising target of EGFR for lung cancer treatment has been identified, providing a potential avenue for more effective therapies. The purpose of the study was to design a library of 1843 coumarin-1,2,3-triazole hybrids and screen them based on a designed pharmacophore to identify potential inhibitors targeting EGFR in lung cancer with minimum or no side effects. Pharmacophore-based screening was carried out and 60 hits were obtained. To gain a better understanding of the binding interactions between the compounds and the targeted receptor, molecular docking was conducted on the 60 screened compounds. In-silico ADME and toxicity studies were also conducted to assess the drug-likeness and safety of the identified compounds. The results indicated that coumarin-1,2,3-triazole hybrids COUM-0849, COUM-0935, COUM-0414, COUM-1335, COUM-0276, and COUM-0484 exhibit dock score of - 10.2, - 10.2, - 10.1, - 10.1, - 10, - 10 while reference molecule - 7.9 kcal/mol for EGFR (PDB ID: 4HJO) respectively. The molecular docking and molecular dynamics simulations revealed that the identified compounds formed stable interactions with the active site of EGFR, indicating their potential as inhibitors. The in-silico ADME and toxicity studies showed that the compounds had favorable drug-likeness properties and low toxicity, further supporting their potential as therapeutic agents. Finally, we performed DFT studies on the best-selected ligands to gain further insights into their electronic properties. The findings of this study provide important insights into the potential of coumarin-1,2,3-triazole hybrids as promising EGFR inhibitors for the management of lung cancer.

3.
Molecules ; 28(8)2023 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-37110860

RESUMEN

Organic solar cells (OSCs) made of electron-acceptor and electron-donor materials have significantly developed in the last decade, demonstrating their enormous potential in cutting-edge optoelectronic applications. Consequently, we designed seven novel non-fused ring electron acceptors (NFREAs) (BTIC-U1 to BTIC-U7) using synthesized electron-deficient diketone units and reported end-capped acceptors, a viable route for augmented optoelectronic properties. The DFT and TDDFT approaches were used to measure the power conversion efficiency (PCE), open circuit voltage (Voc), reorganization energies (λh, λe), fill factor (FF), light harvesting efficiency (LHE) and to evaluate the potential usage of proposed compounds in solar cell applications. The findings confirmed that the photovoltaic, photophysical, and electronic properties of the designed molecules BTIC-U1 to BTIC-U7 are superior to those of reference BTIC-R. The TDM analysis demonstrates a smooth flow of charge from the core to the acceptor groups. Charge transfer analysis of the BTIC-U1:PTB7-Th blend revealed orbital superposition and successful charge transfer from HOMO (PTB7-Th) to LUMO (BTIC-U1). The BTIC-U5 and BTIC-U7 outperformed the reference BTIC-R and other developed molecules in terms of PCE (23.29% and 21.18%), FF (0.901 and 0.894), normalized Voc (48.674 and 44.597), and Voc (1.261 eV and 1.155 eV). The proposed compounds enclose high electron and hole transfer mobilities, making them the ideal candidate for use with PTB7-Th film. As a result, future SM-OSC design should prioritize using these constructed molecules, which exhibit excellent optoelectronic properties, as superior scaffolds.

4.
J Drugs Dermatol ; 21(1): 66-70, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-35005860

RESUMEN

BACKGROUND: Deoxycholic acid is an FDA-approved injectable for treatment of excess submental fat. OBJECTIVE: Study purpose was to evaluate the safety and efficacy of deoxycholic acid for reduction of upper inner thigh fat. METHODS AND MATERIALS: Fifteen subjects received 2–4 treatment sessions of deoxycholic acid 10 mg/mL injected into upper inner thigh fat. Subjects were followed to 12 weeks after last treatment. Adverse events were monitored. Efficacy measures were changes in thigh circumference, upper inner thigh skin fold thickness, and “thigh gap;” and percent accuracy by two independent blinded physicians in identifying post-treatment photographs. Patient satisfaction was assessed with questionnaires. RESULTS: There were no serious adverse events. All patients experienced expected side effects. At 12-week follow-up, decreases in thigh circumference (average change -2.2 cm) and upper inner thigh skin fold thickness (average change -8.8 mm) were observed. Average increase in “thigh gap” was 1.6 cm. Two blinded investigators correctly identified the post-treatment photograph for 83% of patients. On Subject Self-Rating Scale (6-point scale), there was average +3.0 improvement; 86% of patients were satisfied with treatment. CONCLUSION: Deoxycholic acid injection was safe and effective for reduction of upper inner thigh fat in this Phase I study. J Drugs Dermatol. 2022;21(1):66-70. doi:10.36849/JDD.5919.


Asunto(s)
Técnicas Cosméticas , Ácido Desoxicólico , Muslo , Ácido Desoxicólico/efectos adversos , Humanos , Inyecciones Subcutáneas , Satisfacción del Paciente , Grasa Subcutánea , Resultado del Tratamiento
5.
J Allergy Clin Immunol ; 147(3): 955-966.e16, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32634452

RESUMEN

BACKGROUND: Staphylococcus aureus and Staphylococcus epidermidis are the most abundant bacteria found on the skin of patients with atopic dermatitis (AD). S aureus is known to exacerbate AD, whereas S epidermidis has been considered a beneficial commensal organism. OBJECTIVE: In this study, we hypothesized that S epidermidis could promote skin damage in AD by the production of a protease that damages the epidermal barrier. METHODS: The protease activity of S epidermidis isolates was compared with that of other staphylococcal species. The capacity of S epidermidis to degrade the barrier and induce inflammation was examined by using human keratinocyte tissue culture and mouse models. Skin swabs from atopic and healthy adult subjects were analyzed for the presence of S epidermidis genomic DNA and mRNA. RESULTS: S epidermidis strains were observed to produce strong cysteine protease activity when grown at high density. The enzyme responsible for this activity was identified as EcpA, a cysteine protease under quorum sensing control. EcpA was shown to degrade desmoglein-1 and LL-37 in vitro, disrupt the physical barrier, and induce skin inflammation in mice. The abundance of S epidermidis and expression of ecpA mRNA were increased on the skin of some patients with AD, and this correlated with disease severity. Another commensal skin bacterial species, Staphylococcus hominis, can inhibit EcpA production by S epidermidis. CONCLUSION: S epidermidis has commonly been regarded as a beneficial skin microbe, whereas S aureus has been considered deleterious. This study suggests that the overabundance of S epidermidis found on some atopic patients can act similarly to S aureus and damage the skin by expression of a cysteine protease.


Asunto(s)
Proteínas Bacterianas/metabolismo , Proteasas de Cisteína/metabolismo , Dermatitis Atópica/microbiología , Microbiota , Piel/microbiología , Infecciones Cutáneas Estafilocócicas/microbiología , Staphylococcus epidermidis/enzimología , Animales , Péptidos Catiónicos Antimicrobianos/metabolismo , Células Cultivadas , ADN Bacteriano/genética , Dermatitis Atópica/patología , Desmogleína 1/metabolismo , Humanos , Queratinocitos/microbiología , Queratinocitos/patología , Ratones , Ratones Endogámicos C57BL , Índice de Severidad de la Enfermedad , Piel/patología , Infecciones Cutáneas Estafilocócicas/patología , Catelicidinas
6.
J Pak Med Assoc ; 70(10): 1723-1726, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-33159741

RESUMEN

OBJECTIVE: To examine aggression in married men and women in comparison to each other. METHODS: The comparative cross-sectional study was conducted from January to September 2017 in Jinnah, Lyallpur, Madina and Jaranwala towns of Faisalabad in the Punjab province of Pakistan, and comprised an equal number of married men and women. Data was collected using a demographic information form and the Aggression Questionnaire. SPSS 20 was used for data analysis. RESULTS: Of the 300 subjects, 150(50%) each were men and women. Among the men, 90(60%) and 110(73%) among the women were in the 31-40 years age bracket. The men showed significantly higher tendency towards physical aggression while verbal aggression was found more in women (p<0.05). The difference was non-significant with respect to anger and hostility (p>0.05). CONCLUSIONS: Married men were found to be more involved in physical aggression than married women. Conversely, married women were found to be more involved in verbal aggression than married men. Anger and hostility were traits common in both genders.


Asunto(s)
Agresión , Hostilidad , Ira , Estudios Transversales , Femenino , Humanos , Masculino , Pakistán
7.
Lasers Surg Med ; 2018 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-29436720

RESUMEN

BACKGROUND AND OBJECTIVE: Basal cell carcinoma (BCC) is an indolent form of skin cancer that is rarely life threatening, but can cause significant cosmetic and functional morbidity. Surgical treatments often result in disfiguring scars, while topical therapies frequently result in recurrence. The need for a more effective nonsurgical alternative has led to the investigation of laser treatment of BCC. We have previously conducted a pilot study which showed 100% histologic clearance at high fluences. Treatments were well tolerated with no significant adverse events. The objective of this larger study was to confirm preliminary results that the 1064 nm Nd:YAG laser is a safe and effective method for treating non-facial BCC. DESIGN: This is an IRB-approved, prospective, multi-center study evaluating the safety and efficacy of the 1064 nm Nd:YAG laser for the treatment of BCC on the trunk and extremities. Thirty-three subjects seeking treatment for biopsy-proven BCC that did not meet the criteria for Mohs surgery were recruited. Subjects on current anticoagulation therapy, or with a history of immunosuppression were excluded. Subjects received one treatment with the 1064 nm Nd:YAG laser as follows: 5-6 mm spot, fluence of 125-140 J/cm2 and a pulse duration of 7-10 ms. Standard excision with 5 mm clinical margins was performed at 30 days after laser treatment to evaluate clinical and histologic clearance of BCC. Standardized photographs and adverse assessments were taken at the baseline visit, immediately after laser treatment and on the day of excision. RESULTS: Thirty-one subjects completed the study. BCC tumors had a 90% (28 of 31 BCC tumors) histologic clearance rate after one treatment with the long-pulsed 1064 nm Nd:YAG laser. Treatments were generally well tolerated without any anesthesia. Immediate side effects included edema and erythema. At 1-month follow-up, some patients had residual crusting. No significant adverse events occurred. CONCLUSION: The 1064 nm long-pulsed Nd:YAG laser is an alternative for treating non-facial BCC for those that are poor surgical candidates. Lasers Surg. Med. © 2018 Wiley Periodicals, Inc.

8.
J Mol Model ; 30(3): 76, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38376621

RESUMEN

CONTEXT: The purpose of the S01-S05 series of end-capped modified donor chromophores is to amplify the energy conversion efficiency of organic solar cells. Using quantum chemical modeling, the photophysical and photoelectric characteristics of the S01-S05 geometries are examined. METHOD: The influence of side chain replacement on multiple parameters, including the density of states (DOS), molecular orbital analysis (FMOS), exciton-binding energy (Eb), molecular electrostatic potential analysis, dipole moment (µ), and photovoltaic characteristics including open circuit voltage (VOC), and PCE at minimal energy state geometries, has been investigated employing density functional theory along with TD-DFT analysis. The molar absorption coefficient (λmax) of all the proposed compounds (S01-S05) was efficiently enhanced by the terminal acceptor alteration technique, as demonstrated by their scaling up with the reference molecule (SR). Among all molecules, S04 has shown better absorption properties with a red shift in absorption having λmax at 845 nm in CHCl3 solvent and narrow energy gap (EG) 1.83 eV with least excitation energy (Ex) of 1.4657 eV. All created donors exhibited improved FF and VOC than the SR, which significantly raised PCE and revealed their great efficiency as OSC. Consequently, the results recommended these star-shaped molecules as easily attainable candidates for constructing extremely efficient OSCs.

9.
J Cosmet Dermatol ; 23(1): 145-153, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38018479

RESUMEN

BACKGROUND: A new antioxidant serum has been formulated with sodium ascorbate, a sodium salt of Vit C, which aims to address facial photodamage while maintaining a low irritation profile and preserving elastin. Detailed background science has been submitted in a previous publication. This open-label study was conducted to validate the science by demonstrating product efficacy and tolerability in patients with moderate to severe facial photodamage. METHODS: A multicenter, open-label clinical study was undertaken over 5 months from March 2023 to July 2023. Thirty six eligible participants (35 female, 1 male), aged 38-69 years, and Fitzpatrick skin types II-V were enrolled into and completed the study following 12 weeks of the topical antioxidant serum use twice daily, along with the following supporting products (gentle cleanser, moisturizer, and sunscreen for as needed use). Follow-up visits were conducted in Weeks 2, 4, 8, and 12. At every visit, participants were evaluated for facial photodamage severity and test product tolerability. Additionally, study participants underwent subject assessments and satisfaction questionnaires, investigator assessments, biopsy collection, and photography. RESULTS: Significant improvements in all evaluated facial photodamage parameters were observed at 12 weeks together with excellent tolerability and subject satisfaction persisting to Week 12 at study completion. Histology most notably revealed increased elastin fibers in 5 out of 5 post 12-week treatment biopsies on Movat staining, while Herovici stains revealed stimulation of collagen and early formation of new fibers. CONCLUSION: A novel antioxidant serum has demonstrated to be safe and effective for addressing facial photodamage, while stimulating the production of both elastin and collagen in the extracellular matrix (ECM).


Asunto(s)
Antioxidantes , Envejecimiento de la Piel , Femenino , Humanos , Masculino , Antioxidantes/uso terapéutico , Ácido Ascórbico/uso terapéutico , Colágeno , Elastina , Resultado del Tratamiento , Adulto , Persona de Mediana Edad , Anciano
10.
J Am Acad Dermatol ; 69(4): 570-7, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23871720

RESUMEN

BACKGROUND: Excess cathelicidin and kallikrein 5 (KLK5) have been hypothesized to play a role in the pathophysiology of rosacea. OBJECTIVE: We sought to evaluate the effects of azelaic acid (AzA) on these elements of the innate immune system. METHODS: Gene expression and protease activity were measured in laboratory models and patients with rosacea during a 16-week multicenter, prospective, open-label study of 15% AzA gel. RESULTS: AzA directly inhibited KLK5 in cultured keratinocytes and gene expression of KLK5, Toll-like receptor-2, and cathelicidin in mouse skin. Patients with rosacea showed reduction in cathelicidin and KLK5 messenger RNA after treatment with AzA gel. Subjects without rosacea had lower serine protease activity (SPA) than patients with rosacea. Distinct subsets of patients with rosacea who had high and low baseline SPA were identified, and patients with high baseline exhibited a statistically significant reduction of SPA with 15% AzA gel treatment. LIMITATIONS: Study size was insufficient to predict clinical efficacy based on the innate immune response to AzA. CONCLUSIONS: These results show that cathelicidin and KLK5 decrease in association with AZA exposure. Our observations suggest a new mechanism of action for AzA and that SPA may be a useful biomarker for disease activity.


Asunto(s)
Péptidos Catiónicos Antimicrobianos/metabolismo , Ácidos Dicarboxílicos/uso terapéutico , Calicreínas/metabolismo , Rosácea/tratamiento farmacológico , Rosácea/metabolismo , Serina Proteasas/metabolismo , Administración Tópica , Adulto , Anciano , Animales , Péptidos Catiónicos Antimicrobianos/efectos de los fármacos , Péptidos Catiónicos Antimicrobianos/genética , Biomarcadores/metabolismo , Células Cultivadas/efectos de los fármacos , Células Cultivadas/metabolismo , Estudios de Cohortes , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Ensayo de Inmunoadsorción Enzimática , Femenino , Estudios de Seguimiento , Geles , Humanos , Calicreínas/efectos de los fármacos , Calicreínas/genética , Queratinocitos/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos BALB C , Persona de Mediana Edad , Estudios Prospectivos , Valores de Referencia , Factores de Riesgo , Rosácea/diagnóstico , Serina Proteasas/efectos de los fármacos , Serina Proteasas/genética , Resultado del Tratamiento , Catelicidinas
11.
J Cosmet Dermatol ; 22(12): 3320-3328, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37853849

RESUMEN

BACKGROUND: This paper describes the background research and validation related to the formulation of a novel antioxidant product. Two defined outcomes were sought. Firstly, a combined efficacy of antioxidant ingredients in quenching free oxygen radicals. Secondly, the investigation into whether a vitamin C derivative sodium salt was elastin conserving in contrast to current vitamin C/l-ascorbic acid variations that have been reported to negatively affect elastin constitution and regeneration. MATERIALS AND METHODS: A leading l-ascorbic acid antioxidant available on the market was compared with the experimental new product in two studies. In the first experiment, the products were compared to assess their antioxidant properties. The evaluated products TOPICAL ANTIOXIDANT 1 and TOPICAL ANTIOXIDANT 2 were applied to human skin cultures (25-30 mg/cm2 ) for a total of 72 h of treatment and exposed to oxidative stress. The generation of free radicals was semi-quantitatively assessed by measuring the fluorescence intensity of the deacetylation and oxidation of the probe dichlorofluorescein diacetate (DCFH-DA). In the second experiment, an ex vivo skin model (derived from patients undergoing facelift procedures) was used to assess elastin preservation. Three skin explants were topically subjected to the two formulations daily for 7 days. The skin was then prepared and fixed for immunofluorescent assessment after staining with CD44 and tropoelastin antibodies. Images were then analyzed using ImageJ. RESULTS: A full description of the different components selected for the new formulation is presented. In the first study, the experimental formulation performed with absolute equivalence to the comparator in its radical quenching capacity; both showed extremely effective antioxidant function. In the second study, the comparator negatively affected the existing elastin with areas of breakdown and diminished staining. In contrast, the new formulation showed good conservation of healthy elastin in all sections demonstrating elastin preservation. CONCLUSION: A new antioxidant formulation was carefully designed with multiple actives that show an equivalent antioxidant capacity to a leading product on the market. More importantly, the vitamin C component shows direct elastin conservation and improvement as opposed to the comparator, which had negative effects on elastin preservation. This is in keeping with little-known literature reports on vitamin C and its negative effects on elastin and validates the use of a sodium salt derivative, which appears to have protective effects on elastin. These findings support the overall regenerative extracellular matrix changes seen with TriHex® technology in other products.


Asunto(s)
Antioxidantes , Ácido Ascórbico , Humanos , Ácido Ascórbico/farmacología , Elastina , Vitaminas , Radicales Libres , Sodio
12.
J Mol Model ; 29(12): 373, 2023 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-37957312

RESUMEN

CONTEXT: The development of high-efficiency photovoltaic devices is the need of time with increasing demand for energy. Herein, we designed seven small molecule donors (SMDs) with A-π-D-π-A backbones containing various acceptor groups for high-efficiency organic solar cells (OSCs). Molecular engineering was performed by substituting the acceptor group in the synthesized compound (BPR) with another highly efficient acceptor group to improve the photoelectric performance of the molecule. METHOD: The photovoltaic, optoelectronic, and photophysical properties of the proposed compounds (BP1-BP7) were investigated in comparison to BPR using DFT and TD-DFT at MPW1PW91/6-311G(d,p) level of theory. All molecules we designed have red-shifted absorption spectra. The modification of the acceptor fragment of the BPR resulted in a reduced HOMO-LUMO energy gap; thus, the designed compounds (BP1-BP7) had improved optoelectronic responses as compared with the BPR molecule. Various key factors that are crucial for efficient SMDs such as exciton binding energy, frontier molecular orbitals (FMOs), absorption maximum (λmax), open circuit voltage (VOC), dipole moment (µ), excitation charge mobilities, and the transition density matrix of (BPR, BP1-BP7) have also been studied. Low reorganizational energy (holes and electrons) values provide high charge mobility, and all the designed compounds are efficient in this regard. Here, BP6 exhibits low excitation energy (1.66 eV), highest open circuit voltage (2.00 V), normalized VOC (77.23), and fill factor (0.931). Consequently, the superiority of the designed molecules advises experimenters to envision future developments in extremely effective OSC devices.

13.
J Mol Model ; 29(8): 237, 2023 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-37420131

RESUMEN

CONTEXT: The present study aims to improve the performance of optoelectronics and photovoltaics by constructing an acceptor-donor-acceptor (A-D-A) molecule with a fullerene-free acceptor moiety. The study utilizes malononitrile and selenidazole derivatives to tailor the molecule for enhanced photovoltaic abilities. The study analyzes molecular properties and parameters like charge density, charge transport, UV absorption spectra, exciton binding energies, and electron density difference maps to determine the effectiveness of the tailored derivatives. METHODS: To optimize the geometric structures, the study used four different functionals (B3LYP, CAM-B3LYP, MPW1PW91, and É·B97XD) along with a double zeta valence basis set 6-31G(d, p) basis set. The study compared the results of the tailored derivatives with a reference molecule (R-P2F) to determine improvements in performance. The light harvesting efficiency of the molecules was analyzed by performing simulations in the gas and solvent phases (chloroform) based on the spectral overlap between the solar irradiance and the absorption spectra of the molecules. The open-circuit voltage (VOC) of each molecule was also analyzed, representing the maximum voltage that can be obtained from the cell under illuminated conditions. The findings indicated that the M1-P2F designed derivative is a more effective, with energy gap of 2.14 eV, and suitable candidate for non-fullerene organic solar cell application, based on various analyses such as power conversion efficiency, quantum chemical reactivity parameters, and electronic features.


Asunto(s)
Cloroformo , Fulerenos , Electrónica , Solventes
14.
Cell Rep ; 42(5): 112494, 2023 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-37167061

RESUMEN

During inflammation, the skin deploys antimicrobial peptides (AMPs) yet during allergic inflammation it becomes more susceptible to Staphylococcus aureus. To understand this contradiction, single-cell sequencing of Il4ra-/- mice combined with skin microbiome analysis reveals that lower production of AMPs from interleukin-4 receptor α (IL-4Rα) activation selectively inhibits survival of antibiotic-producing strains of coagulase-negative Staphylococcus (CoNS). Diminished AMPs under conditions of T helper type 2 (Th2) inflammation enable expansion of CoNS strains without antibiotic activity and increase Staphylococcus aureus (S. aureus), recapitulating the microbiome on humans with atopic dermatitis. This response is rescued in Camp-/- mice or after topical steroids, since further inhibition of AMPs enables survival of antibiotic-producing CoNS strains. In conditions of Th17 inflammation, a higher expression of host AMPs is sufficient to directly inhibit S. aureus survival. These results show that antimicrobials produced by the host and commensal bacteria each act to control S. aureus on the skin.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Infecciones Estafilocócicas , Humanos , Animales , Ratones , Staphylococcus aureus/metabolismo , Péptidos Antimicrobianos , Piel/microbiología , Inflamación , Bacterias , Staphylococcus , Antibacterianos/metabolismo
15.
Sci Transl Med ; 14(632): eabh1478, 2022 02 16.
Artículo en Inglés | MEDLINE | ID: mdl-35171653

RESUMEN

Innate immune defense against deep tissue infection by Staphylococcus aureus is orchestrated by fibroblasts that become antimicrobial when triggered to differentiate into adipocytes. However, the role of this process in noninfectious human diseases is unknown. To investigate the potential role of adipogenesis by dermal fibroblasts in acne, a disorder triggered by Cutibacterium acnes, single-cell RNA sequencing was performed on human acne lesions and mouse skin challenged by C. acnes. A transcriptome consistent with adipogenesis was observed within specific fibroblast subsets from human acne and mouse skin lesions infected with C. acnes. Perifollicular dermal preadipocytes in human acne and mouse skin lesions showed colocalization of PREF1, an early marker of adipogenesis, and cathelicidin (Camp), an antimicrobial peptide. This capacity of C. acnes to specifically trigger production of cathelicidin in preadipocytes was dependent on TLR2. Treatment of wild-type mice with retinoic acid (RA) suppressed the capacity of C. acnes to form acne-like lesions, inhibited adipogenesis, and enhanced cathelicidin expression in preadipocytes, but lesions were unresponsive in Camp-/- mice, despite the anti-adipogenic action of RA. Analysis of inflamed skin of acne patients after retinoid treatment also showed enhanced induction of cathelicidin, a previously unknown beneficial effect of retinoids in difficult-to-treat acne. Overall, these data provide evidence that adipogenic fibroblasts are a critical component of the pathogenesis of acne and represent a potential target for therapy.


Asunto(s)
Acné Vulgar , Antiinfecciosos , Enfermedades de la Piel , Animales , Antibacterianos/farmacología , Antiinfecciosos/farmacología , Humanos , Ratones , Propionibacterium acnes/metabolismo , Staphylococcus aureus , Tretinoina/farmacología
16.
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.

17.
Nat Med ; 27(4): 700-709, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33619370

RESUMEN

Staphylococcus aureus colonizes patients with atopic dermatitis (AD) and exacerbates disease by promoting inflammation. The present study investigated the safety and mechanisms of action of Staphylococcus hominis A9 (ShA9), a bacterium isolated from healthy human skin, as a topical therapy for AD. ShA9 killed S. aureus on the skin of mice and inhibited expression of a toxin from S. aureus (psmα) that promotes inflammation. A first-in-human, phase 1, double-blinded, randomized 1-week trial of topical ShA9 or vehicle on the forearm skin of 54 adults with S. aureus-positive AD (NCT03151148) met its primary endpoint of safety, and participants receiving ShA9 had fewer adverse events associated with AD. Eczema severity was not significantly different when evaluated in all participants treated with ShA9 but a significant decrease in S. aureus and increased ShA9 DNA were seen and met secondary endpoints. Some S. aureus strains on participants were not directly killed by ShA9, but expression of mRNA for psmα was inhibited in all strains. Improvement in local eczema severity was suggested by post-hoc analysis of participants with S. aureus directly killed by ShA9. These observations demonstrate the safety and potential benefits of bacteriotherapy for AD.


Asunto(s)
Dermatitis Atópica/microbiología , Dermatitis Atópica/terapia , Piel/microbiología , Staphylococcus hominis/fisiología , Administración Tópica , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Animales , Proteínas Bacterianas/metabolismo , Bacteriocinas/farmacología , Recuento de Colonia Microbiana , Humanos , Inflamación/complicaciones , Inflamación/patología , Ratones Endogámicos BALB C , Pruebas de Sensibilidad Microbiana , Viabilidad Microbiana/efectos de los fármacos , Persona de Mediana Edad , Péptidos Cíclicos/metabolismo , Reproducibilidad de los Resultados , Piel/efectos de los fármacos , Piel/patología , Infecciones Estafilocócicas/microbiología , Infecciones Estafilocócicas/terapia , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/crecimiento & desarrollo , Staphylococcus aureus/fisiología , Transcripción Genética/efectos de los fármacos , Resultado del Tratamiento , Factores de Virulencia/metabolismo , Adulto Joven
18.
Seizure ; 45: 95-99, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27978485

RESUMEN

PURPOSE: Nocebo is very prevalent among neurological diseases resulting in low adherence and treatment outcome. We sought to examine the AEs following placebo administration in Randomized Controlled Studies (RCTs) for Epilepsy. METHOD: After a systematic Medline search for RCTs for Epilepsy pharmacological treatments, we assessed the number of discontinuations because of placebo intolerance. RESULTS: Data were extracted from 4 RCTs fulfilling our search criteria. Three out of 5 placebo-treated patients (60.8%) reported at least one AE and 4.0% discontinued placebo treatment because of AEs. All patients participating in the epilepsy RCTs reported similar AEs independently of the study arm they belonged. CONCLUSION: Very limited epilepsy RCTs with pure placebo groups are available and all are in treatment resistant patients during pre-surgical monitoring. However, our study indicates a significant nocebo effect in trials for epilepsy treatment adversely affecting adherence and efficacy of current treatments in clinical practice, with additional implications for trial designing.


Asunto(s)
Epilepsia Refractaria/tratamiento farmacológico , Epilepsia Refractaria/psicología , Efecto Nocebo , Cuidados Preoperatorios , Ensayos Clínicos Controlados Aleatorios como Asunto , Epilepsia Refractaria/cirugía , Humanos , MEDLINE
19.
Artículo en Inglés | MEDLINE | ID: mdl-28593798

RESUMEN

INTRODUCTION: Nocebo is very prevalent among neurological disorders, resulting in low adherence and treatment outcome. We sought to examine the AEs following placebo administration in placebo-controlled randomised clinical trials (RCTs) for motor neuron disease (MND). METHODS: After a systematic literature search for RCTs for MND pharmacotherapy treatments, we assessed the number of discontinuations because of placebo intolerance. RESULTS: Data were extracted from 12 RCTs fulfilling our search criteria. Approximately eight in 10 placebo-treated patients (78.3%, 95% CI 74.3-82.0%) reported at least one AE and approximately one in 12 placebo-treated patients discontinued placebo treatment because of AEs (8.4%, 95% CI 6.7-10.4%). All patients participating in the MND trials reported similar AEs independently of the study arm to which they belonged. CONCLUSION: Our study indicates significant nocebo in trials for MND treatment, adversely affecting adherence and efficacy of current treatments in clinical practice, with additional implications for trial design.


Asunto(s)
Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/epidemiología , Enfermedad de la Neurona Motora/tratamiento farmacológico , Enfermedad de la Neurona Motora/epidemiología , Fármacos Neuroprotectores/uso terapéutico , Efecto Nocebo , Ensayos Clínicos Controlados Aleatorios como Asunto/estadística & datos numéricos , Medicina Basada en la Evidencia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Factores de Riesgo , Resultado del Tratamiento
20.
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
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