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1.
Public Health ; 224: 32-40, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37708714

RESUMO

OBJECTIVES: The purpose of this study was to evaluate food insecurity on body mass index (BMI) and diet-related behaviors among college students and whether psychological well-being (PWB) and stress levels mediate this relationship. STUDY DESIGN: This was a cross-sectional study. METHODS: Data from 1439 students from the American College Health Association National College Health Assessment III (Fall 2020) were used. Food security status was evaluated by the USDA Six-Item Short Form. PWB was measured using the Diener Flourishing Scale. Diet-related behaviors included the average servings of fruits, vegetables, and sugar-sweetened beverages consumed per day. Stress was measured by self-reported levels. Regression model analysis evaluated the influence of food security status, PWB, and stress levels on BMI. PWB and stress were also tested as mediators in the relationship between food insecurity and BMI. RESULTS: Among our sample of college students, 44.54% (n = 641) were food insecure, and 55.46% (n = 798) were food secure. Multiple regression analysis showed that higher food insecurity, older age, full-time enrollment status, and fifth-year student status were positively associated with a higher BMI score (P < 0.05). Results from mediation models revealed that PWB, but not stress, mediated the relationship between food security and BMI among Black/African American students. Regarding diet-related behaviors, high stress levels mediated the relationship between food insecurity and sugar-sweetened beverage intake among students. CONCLUSIONS: Food insecurity appears to influence BMI in college students. This relationship seems to be mediated by disrupted PWB and a higher intake of sugar-sweetened beverages due to stress.

2.
Philos Trans A Math Phys Eng Sci ; 380(2231): 20210369, 2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-35858078

RESUMO

We study a one-dimensional problem arising in strain gradient porous-elasticity. Three different Moore-Gibson-Thompson dissipation mechanisms are considered: viscosity and hyperviscosity on the displacements, and weak viscoporosity. The existence and uniqueness of solutions are proved. The energy decay is also shown, being polynomial for the two first situations, unless a particular choice of the constitutive parameters is made in the hyperviscosity case. Finally, for the weak viscoporosity, only the slow decay can be expected. This article is part of the theme issue 'Wave generation and transmission in multi-scale complex media and structured metamaterials (part 1)'.

3.
Islets ; 14(1): 23-35, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34689719

RESUMO

Intra-islet communication via electrical, paracrine and autocrine signals, is highly dependent on the organization of cells within the islets and is key for an adequate response to changes in blood glucose and other stimuli. In spite of the fact that relevant structural differences between mouse and human islet architectures have been described, the functional implications of these differences remain only partially understood. In this work, aiming to contribute to a better understanding of the relationship between structural and functional properties of pancreatic islets, we reconstructed human and mice islets in order to perform a structural comparison based on both morphologic and network-derived metrics. According to our results, human islets constitute a more efficient network from a connectivity viewpoint, mainly due to the higher proportion of heterotypic contacts between islet cells in comparison to mice islets.


Assuntos
Ilhotas Pancreáticas , Animais , Humanos , Camundongos
4.
J Intern Med ; 288(3): 371-372, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32744390
5.
J Intern Med ; 288(3): 365-367, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32657497
6.
Comput Methods Biomech Biomed Engin ; 23(6): 213-223, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31958016

RESUMO

In this paper, we characterized the hyperelastic and damage behavior of the Extensor Digitorum Longus (EDL) human tendon under loading conditions. The study was conducted in both categories of models, phenomenological and physically motivated, to allow the prediction and the macroscopic response of the tendon under specific loading conditions, assuming that its response follows a hyperelastic anisotropic model in conjunction with damage law. We benchmarked multiple hyperelastic and damage models to fit the response of the tendons in uniaxial tensile loading conditions, and by employing a genetic algorithm, we obtained the material parameters for both elastic and damage models. The objective of this study was to explore different mathematical models to determine which would be the best option to predict the behavior of tendons and ligaments in complex biological systems using Finite Elements (FE) models. Therefore, we took into account accuracy as well as computational features. We considered the model proposed by Shearer and coupled it with a sigmoid function, which governs the evolution of damage in tendons, as the most appropriate for the fitting of the experimental data. The achieved solution shows to be of high interest attributable to the simplicity of the damage law function and its low computational cost.


Assuntos
Elasticidade , Tendões/fisiologia , Algoritmos , Anisotropia , Humanos , Modelos Biológicos , Estresse Mecânico
7.
Pediatr Obes ; 14(2): e12470, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30253082

RESUMO

BACKGROUND: In adults, the Taq1a polymorphism (rs1800497) near the D2 receptor (DRD2) gene is associated with body mass index and binge eating and is more prevalent among non-Hispanic Blacks (NHB) and Hispanic-Americans (HA) relative to non-Hispanic Whites (NHW). We hypothesize Taq1a polymorphism (rs1800497) risk alleles contribute to paediatric racial/ethnic differences in obesity phenotypes. OBJECTIVES: This study aims to characterize the relationship between the Taq1a polymorphism (rs1800497), diet and adiposity in a multi-ethnic cohort of 286 children (98 NHB, 76 HA and 112 NHW), ages 7-12. METHODS: Dual-energy X-ray absorptiometry, computed tomography scans and two 24-h dietary recalls assessed body composition, fat distribution and dietary intakes, respectively. RESULTS: Children with two Taq1a risk alleles (NHB = 50.0%, HA = 43.3%, NHW = 6.7%) reported a 20% increase in total energy intake (P = 0.0034) and per cent of calories from sugar consumed (P = 0.0077) than did children with less than two risk alleles. Children with two Taq1a risk alleles demonstrated significantly higher total body fat (P = 0.0145), body fat percentage (P = 0.0377), intra-abdominal adiposity (P = 0.0459), subcutaneous abdominal adiposity (P = 0.0213) and total abdominal adiposity (P = 0.0209) than did children with one or no Taq1a risk alleles. CONCLUSIONS: Our results suggest that having two Taq1a risk alleles is associated with an increase in reported calorie and sugar consumption and is a potential risk factor for early development of excess adiposity in multi-ethnic children. These results need to be confirmed in a larger sample.


Assuntos
Comportamento Alimentar/etnologia , Obesidade Infantil/genética , Proteínas Serina-Treonina Quinases/genética , Absorciometria de Fóton/métodos , Alabama , Alelos , Antropometria , Composição Corporal/genética , Criança , Estudos de Coortes , Estudos Transversais , Dieta , Etnicidade , Comportamento Alimentar/fisiologia , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Obesidade Infantil/etnologia , Obesidade Infantil/fisiopatologia , Polimorfismo de Nucleotídeo Único , Receptores de Dopamina D2/genética
8.
AIDS Care ; 31(5): 554-562, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30558446

RESUMO

People aging with HIV face social stressors which may negatively affect their overall nutrition. Here, we assess relationships between self-reported measures of depression, perceived stress, social support, and food insecurity with diet quality in older adults with HIV. A retrospective analysis of self-reported data from parent study at The University of Alabama at Birmingham 1917 HIV Clinic was performed. The study sample consisted of sixty people living with HIV (PLWH) with controlled HIV infection (<50 copies/mL), aged 50 years or older who participated in a cross-sectional microbiome study. Dietary intake was measured using the NHANES 12-month Food Frequency Questionnaire (FFQ) and three Automated Self-Administered (ASA) 24-hr diet recalls to calculate diet quality scores using the Mediterranean Diet Score (MDS); alternative Healthy Eating Index (aHEI); and the Recommended Food Score (RFS) indices. Food insecurity was measured with the Food Security Questionnaire (FSQ). Participants completed the following psychosocial scales: (1) depression - Patient Health Questionnaire-8 (PHQ8); (2) perceived stress - Perceived Stress Scale (PSS-10); (3) social support - Multidimensional Scale of Perceived Social Support (MSPSS). Linear regression models were used to investigate relationships among variables controlling for gender and income. The cohort was characterized as follows: Mean age 56 ± 4.6 years, 80% African-American, and 32% women. Mean body mass index (BMI) was 28.4 ± 7.2 with 55% reporting food insecurity. Most participants reported having post-secondary education (53%), although 77% reported annual incomes <$20,000. Food insecurity was independently associated with measures of poor dietary intake: aHEI (ß = -0.08, p = .02) and MDS (ß = -0.23, p < 0.01) and with low dietary intake of fibre (ß = -0.27, p = .04), vitamin E (ß = -0.35, p = .01), folate (ß = -0.31, p = .02), magnesium (ß = -0.34, p = .01) and copper (ß = -0.36, p = .01). These data indicate food insecurity is associated with poor diet quality among PLWH. Clinical interventions are needed to improve food access for PLWH of low SES.


Assuntos
Dieta , Comportamento Alimentar , Abastecimento de Alimentos/estatística & dados numéricos , Infecções por HIV/psicologia , Estresse Psicológico , Idoso , Alabama , Fármacos Anti-HIV/uso terapêutico , Estudos de Coortes , Depressão , Fibras na Dieta , Feminino , Infecções por HIV/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação Nutricional , Inquéritos Nutricionais , Estado Nutricional , Estudos Retrospectivos , Apoio Social , Inquéritos e Questionários
9.
Pediatr Obes ; 14(5): e12499, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30590877

RESUMO

BACKGROUND: Paediatric obesity and insulin resistance (IR) are potentially reversible inflammatory conditions. Long chain polyunsaturated fatty acids omega-3 (LCPUFA-ω3) show anti-inflammatory and metabolic properties, but their clinical efficacy is unclear. OBJECTIVE: The objective of this study is to evaluate whether supplementation with LCPUFA-ω3 for 3 months reduces insulin resistance and weight to adolescents with obesity. METHODS: Double-blind trial of 366 adolescents with obesity randomly assigned to 1.2-g LCPUFA-ω3 (DO3) or 1-g sunflower oil (DP) daily for 3 months; both groups received an energy-restricted diet. Children attended monthly for anthropometric, dietary, and clinical measurements. Basal and final blood samples were obtained to measure metabolic markers and erythrocytes fatty acids. Regression models were used for analysis. RESULTS: A total of 119 DO3 and 126 DP children completed follow-up. At baseline, 92% of children presented IR, 66% hypertriglyceridemia, 37% low-grade inflammation, and 32% metabolic syndrome. Despite erythrocytes LCPUFA-ω3 increased more in DO3 (Median differences = 0.984 w/w%; 95 IC = 0.47, 1.53, P < 0.001), body weight, insulin, and HOMA changed similarly in both groups at the end of intervention. Adjusting for basal values, changes in weight, insulin, and HOMA was not related with supplementation. CONCLUSIONS: Supplementation with LCPUFA-ω3 does not affect body weight or insulin in adolescents with obesity.


Assuntos
Peso Corporal/efeitos dos fármacos , Ácidos Graxos Ômega-3/uso terapêutico , Resistência à Insulina/fisiologia , Obesidade Infantil/tratamento farmacológico , Adolescente , Biomarcadores/sangue , Peso Corporal/fisiologia , Criança , Suplementos Nutricionais , Método Duplo-Cego , Ácidos Graxos Ômega-3/sangue , Feminino , Seguimentos , Humanos , Masculino , Obesidade Infantil/fisiopatologia , Resultado do Tratamento
10.
RSC Adv ; 9(28): 16187-16194, 2019 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35521365

RESUMO

This paper introduces a new mathematical model that is used to compute either the interfacial tension of quiescent axisymmetric pendant/sessile drops and pendant/captive bubbles. This model consists of the Young-Laplace equation, that describes interface shape, together with suitable boundary conditions that guarantee a prescribed volume of drops/bubbles and a fixed position in the capillary. In order to solve the problem numerically, the Young-Laplace equation is discretized by using numerical differentiation and the numerical solutions are obtained applying the well-know Newton method. The paper contains a validation of the new methodology presented for what theoretical bubble/drops are used. Finally, some numerical results are presented for both drops and bubbles of water as well as several surfactant solutions to demonstrate the applicability, versatility and reproducibility of the proposed methodology.

11.
Ann Oncol ; 29(5): 1280-1285, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29788166

RESUMO

Background: The 21-gene recurrence score (RS) (Oncotype DX®; Genomic Health, Redwood City, CA) partitions hormone receptor positive, node negative breast cancers into three risk groups for recurrence. The Anne Arundel Medical Center (AAMC) model has previously been shown to accurately predict RS risk categories using standard pathology data. A pathologic-genomic (P-G) algorithm then is presented using the AAMC model and reserving the RS assay only for AAMC intermediate-risk patients. Patients and methods: A survival analysis was done using a prospectively collected institutional database of newly diagnosed invasive breast cancers that underwent RS assay testing from February 2005 to May 2015. Patients were assigned to risk categories based on the AAMC model. Using Kaplan-Meier methods, 5-year distant recurrence rates (DRR) were evaluated within each risk group and compared between AAMC and RS-defined risk groups. Five-year DRR were calculated for the P-G algorithm and compared with DRR for RS risk groups and the AAMC model's risk groups. Results: A total of 1268 cases were included. Five-year DRR were similar between the AAMC low-risk group (2.7%, n = 322) and the RS < 18 low-risk group (3.4%, n = 703), as well as between the AAMC high-risk group (22.8%, n = 230) and the RS > 30 high-risk group (23.0%, n = 141). Using the P-G algorithm, more patients were categorized as either low or high risk and the distant metastasis rate was 3.3% for the low-risk group (n = 739) and 24.2% for the high-risk group (n = 272). Using the P-G algorithm, 44% (552/1268) of patients would have avoided RS testing. Conclusions: AAMC model is capable of predicting 5-year recurrences in high- and low-risk groups similar to RS. Further, using the P-G algorithm, reserving RS for AAMC intermediate cases, results in larger low- and high-risk groups with similar prognostic accuracy. Thus, the P-G algorithm reliably identifies a significant portion of patients unlikely to benefit from RS assay and with improved ability to categorize risk.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias da Mama/patologia , Testes Genéticos/métodos , Modelos Genéticos , Recidiva Local de Neoplasia/diagnóstico , Algoritmos , Mama/patologia , Mama/cirurgia , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/genética , Neoplasias da Mama/terapia , Quimioterapia Adjuvante/métodos , Análise Custo-Benefício , Feminino , Seguimentos , Testes Genéticos/economia , Humanos , Incidência , Mastectomia , Pessoa de Meia-Idade , Gradação de Tumores , Recidiva Local de Neoplasia/epidemiologia , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/prevenção & controle , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Medição de Risco/economia , Medição de Risco/métodos , Fatores de Tempo , Resultado do Tratamento , Carga Tumoral/genética
12.
J Math Biol ; 76(4): 817-840, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28712030

RESUMO

Eutrophication is a water enrichment in nutrients (mainly phosphorus) that generally leads to symptomatic changes and deterioration of water quality and all its uses in general, when the production of algae and other aquatic vegetations are increased. In this sense, eutrophication has caused a variety of impacts, such as high levels of Chlorophyll a (Chl-a). Consequently, anticipate its presence is a matter of importance to prevent future risks. The aim of this study was to obtain a predictive model able to perform an early detection of the eutrophication in water bodies such as lakes. This study presents a novel hybrid algorithm, based on support vector machines (SVM) approach in combination with the particle swarm optimization (PSO) technique, for predicting the eutrophication from biological and physical-chemical input parameters determined experimentally through sampling and subsequent analysis in a certificate laboratory. This optimization technique involves hyperparameter setting in the SVM training procedure, which significantly influences the regression accuracy. The results of the present study are twofold. In the first place, the significance of each biological and physical-chemical variables on the eutrophication is presented through the model. Secondly, a model for forecasting eutrophication is obtained with success. Indeed, regression with optimal hyperparameters was performed and coefficients of determination equal to 0.90 for the Total phosphorus estimation and 0.92 for the Chlorophyll concentration were obtained when this hybrid PSO-SVM-based model was applied to the experimental dataset, respectively. The agreement between experimental data and the model confirmed the good performance of the latter.


Assuntos
Eutrofização , Lagos , Modelos Biológicos , Algoritmos , Animais , Clorofila A/análise , Biologia Computacional , Lagos/química , Lagos/microbiologia , Lagos/parasitologia , Conceitos Matemáticos , Fósforo/análise , Análise de Regressão , Espanha , Máquina de Vetores de Suporte , Microbiologia da Água , Poluição Química da Água/análise
13.
Pediatr Obes ; 12(5): 347-355, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-27273320

RESUMO

BACKGROUND: Obesity is a global health concern but the United States has reported a leveling in obesity rates in the pediatric population. OBJECTIVE: To provide updated waist circumference (WC) percentile values, identify differences across time and discuss differences within the context of reported weight stabilization in a nationally representative sample of American children. METHODS: Percentiles for WC in self-identified African Americans (AA), European Americans (EA) and Mexican Americans (MA) were obtained from 2009-2014 National Health and Nutrition Examination Survey data (NHANES2014). Descriptive trends across time in 10th, 25th, 50th, 75th and 90th percentile WC distributions were identified by comparing NHANES2012 with previously reported NHANESIII (1988-1994). RESULTS: WC increased in a monotonic fashion in AA, EA and MA boys and girls. When compared with NHANESIII data, a clear left shift of percentile categories was observed such that values that used to be in the 90th percentile are now in the 85th percentile. Differences in WC were observed in EA and MA boys during a reported period of weight stabilization. CONCLUSION AND RELEVANCE: WC has changed in the US pediatric population across time, even during times of reported weight stabilization, particularly among children of diverse racial/ethnic backgrounds.


Assuntos
Peso Corporal , Obesidade Infantil/epidemiologia , Circunferência da Cintura , Adolescente , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Inquéritos Nutricionais , Estados Unidos
14.
J Viral Hepat ; 24(3): 226-237, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27976491

RESUMO

Over the last 5 years, therapies for hepatitis C virus (HCV) infection have improved significantly, achieving sustained virologic response (SVR) rates of up to 100% in clinical trials in patients with HCV genotype 1. We investigated the effectiveness and safety of ombitasvir/paritaprevir/ritonavir±dasabuvir in an early access programme. This was a retrospective, multicentre, national study that included 291 treatment-naïve and treatment-experienced patients with genotype 1 or 4 HCV infection. Most patients (65.3%) were male, and the mean age was 57.5 years. The mean baseline viral load was 6.1 log, 69.8% had HCV 1b genotype, 72.9% had cirrhosis and 34.7% were treatment-naïve. SVR at 12 weeks posttreatment was 96.2%. Four patients had virological failure (1.4%), one leading to discontinuation. There were no statistical differences in virological response according to genotype or liver fibrosis. Thirty patients experienced serious adverse events (SAEs) (10.3%), leading to discontinuation in six cases. Hepatic decompensation was observed in five patients. Four patients died during treatment or follow-up, three of them directly related to liver failure. Multivariate analyses showed a decreased probability of achieving SVR associated with baseline albumin, bilirubin and Child-Pugh score B, and a greater probability of developing SAEs related to age and albumin. This combined therapy was highly effective in clinical practice with an acceptable safety profile and low rates of treatment discontinuation.


Assuntos
Antivirais/uso terapêutico , Genótipo , Hepacivirus/classificação , Hepatite C Crônica/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Quimioterapia Combinada/efeitos adversos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Feminino , Hepacivirus/genética , Hepacivirus/isolamento & purificação , Hepatite C Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Espanha , Resposta Viral Sustentada , Resultado do Tratamento
15.
Dis Aquat Organ ; 120(3): 231-40, 2016 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-27503919

RESUMO

This is the first report of ostreid herpesvirus 1 microvariant (OsHV-1 µVar) infecting natural oyster beds located in Huelva (SW Spain). The virus was detected in 3 oyster species present in the intertidal zone: Crassostrea gigas (Thunberg, 1793), C. angulata (Lamarck, 1819) and, for the first time, in Ostrea stentina Payraudeau, 1826. Oysters were identified by a specific polymerase chain reaction (PCR) and posterior restriction fragment length polymorphism (RFLP) analysis based on cytochrome oxidase I (COI) mitochondrial DNA. Results confirmed that C. angulata still remains the dominant oyster population in SW Spain despite the introduction of C. gigas for cultivation in the late 1970s, and its subsequent naturalization. C. angulata shows a higher haplotype diversity than C. gigas. OsHV-1 virus was detected by PCR with C2/C6 pair primers. Posterior RFLP analyses with the restriction enzyme MfeI were done in order to reveal the OsHV-1 µVar. Detections were confirmed by DNA sequencing, and infections were evidenced by in situ hybridization in C. gigas, C. angulata and O. stentina samples. The prevalence was similar among the 3 oyster species but varied between sampling locations, being higher in areas with greater harvesting activities. OsHV-1 µVar accounted for 93% of all OsHV-1 detected.


Assuntos
Crassostrea/virologia , Herpesviridae/isolamento & purificação , Animais , Haplótipos , Herpesviridae/genética , Interações Hospedeiro-Patógeno , Espanha , Especificidade da Espécie
19.
Br J Nutr ; 113(11): 1792-9, 2015 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-25869232

RESUMO

Socio-economic status (SES) has been associated with measures of diet quality; however, such measures have not directly captured overall eating practices in individuals. Based on the factor analysis of fifty-six food groups from FFQ, associations between patterns of food consumption and SES were examined in a nationwide sample of 17,062 black (34·6%) and white participants (age >45 years) from the REasons for Geographic And Racial Differences in Stroke (REGARDS) study. Logistic regression models adjusted for age, sex, racial group and geographic region were used to examine adherence to five emergent dietary patterns (convenience, plant-based, sweets/fats, southern and alcohol/salads) according to four levels each of individual education, household income and community-level SES. Further models assessed adherence to these dietary patterns by racial group, and an overall model including both racial groups examined whether the relationships between SES and adherence to these dietary patterns differed among black and white participants. For all the three measures of SES, higher SES had been associated with greater adherence to plant-based and alcohol/salads patterns, but lower adherence to sweets/fats and southern patterns. Statistically significant differences between black and white participants were observed in the associations between household income and adherence to alcohol/salads, individual education and adherence to plant-based and sweets/fats, and community SES and adherence to convenience patterns. As adherence to dietary patterns has been shown to be associated with health outcomes in this population (e.g. stroke), the present study offers valuable insight into behavioural and environmental factors that may contribute to health disparities in the diverse US population.


Assuntos
Negro ou Afro-Americano , Dieta , Fatores Socioeconômicos , População Branca , Idoso , Ingestão de Energia , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Avaliação Nutricional , Estudos Observacionais como Assunto , Cooperação do Paciente , Estados Unidos
20.
Int J Cosmet Sci ; 37(1): 129-33, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25256809

RESUMO

BACKGROUND: The skin is the first line of defence against exposure to microbial, physical, environmental and chemical insults. In mobilizing a protective response, several different cell types located in our skin release and respond to pro-inflammatory cytokines ensuring skin homeostasis and health. However, chronic activation of this response eventually causes damage resulting in premature ageing. Diosodium tetramethylhexadecenyl succinyl cysteine (TSC or SIG1273), an isoprenylcysteine small molecule, down modulates these inflammatory signalling pathways in various cell types (keratinocytes, peripheral blood mononuclear cells (PBMCs) and endothelial cells) and possesses anti-bacterial properties. Thus, TSC represents a novel cosmetic functional ingredient that provides a broad spectrum of benefits for the skin. OBJECTIVE: To assess the anti-inflammatory properties of TSC in several cutaneous cell types and further investigate its anti-microbial activity. METHODS: Cultured normal human epidermal keratinocytes were exposed to chemical irritant phorbol 12-myrisate 13-acetate (TPA) or ultraviolet-B light (UVB) to induce pro-inflammatory cytokine (IL-6, IL-8 and TNF-α) production. T-cell receptor (TCR) activation of PBMCs and nickel (Ni(2+) ) treatments of human dermal microvascular endothelial cells (HDMECs) were performed resulting in IL-4, IL-6, IL-8 and IL-17 production. Streptococcus pyogenes were cultured to determine minimal inhibitory concentration values. RESULTS: In vitro studies demonstrate TSC blocks TPA and UVB-induced cytokine production in cultured keratinocytes. Similarly, TSC inhibits overproduction of IL-4 and IL-17 in T-cell receptor (TCR)-activated PBMCs as well as nickel induction of IL-6 and IL-8 in HDMECs. Lastly, TSC demonstrated anti-microbial properties, inhibiting cell growth of S. pyogenes. CONCLUSIONS: Tetramethylhexadecenyl succinyl cysteine represents a novel cosmetic functional ingredient that provides a dual modulating benefit of skin protection to individuals by reducing inflammation in keratinocytes, endothelial and mononuclear cell types and S. pyogenes counts.


Assuntos
Antibacterianos/farmacologia , Anti-Inflamatórios/farmacologia , Cosméticos , Cisteína/análogos & derivados , Células Cultivadas , Cisteína/química , Humanos
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