In certain applications copolymer P123 (E21P67E21) is dissolved in water-ethanol mixtures, initially to form micellar solutions and eventually to gel. For P123 in 10, 20, and 30 wt % aqueous ethanol we used dynamic light scattering from dilute solutions to confirm micellization, oscillatory rheometry, and visual observation of mobility (tube inversion) to determine gel formation in concentrated solutions and small-angle X-ray scattering (SAXS) to determine gel structure. Except for solutions in 30 wt % aqueous ethanol, a clear-turbid transition was encountered on heating dilute and concentrated micellar solutions alike, and as for solutions in water alone (Chaibundit et al. Langmuir 2007, 23, 9229) this could be ascribed to formation of wormlike micelles. Dense clouding, typical of phase separation, was observed at higher temperatures. Regions of isotropic and birefringent gel were defined for concentrated solutions and shown (by SAXS) to have cubic (fcc and hcp) and hexagonal structures, consistent with packed spherical and elongated micelles, respectively. The cubic gels (0, 10, and 20 wt % ethanol) were clear, while the hex gels were either turbid (0 and 10 wt % ethanol), turbid enclosing a clear region (20 wt % ethanol), or entirely clear (30 wt % ethanol). The SAXS profile was unchanged between turbid and clear regions of the 20 wt % ethanol gel. Temperature scans of dynamic moduli showed (as expected) a clear distinction between high-modulus cubic gels (G'max approximately 20-30 kPa) and lower modulus hex gels (G'max<10 kPa).
IMT significantly increases over 2 years in patients with SLE. Age, baseline IMT, C3, C5a anaphylatoxin and homocysteine are all associated risk factors, supporting a role for complement and homocysteine in the early stages of premature SLE-associated atherosclerosis.
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for the current coronavirus disease 2019 (COVID-19) pandemic, affecting more than 219 countries and causing the death of more than 5 million people worldwide. The genetic background represents a factor that predisposes the way the host responds to SARS-CoV-2 infection. In this sense, genetic variants of ACE and ACE2 could explain the observed interindividual variability to COVID-19 outcomes. In order to improve the understanding of how genetic variants of ACE and ACE2 are involved in the severity of COVID-19, we included a total of 481 individuals who showed clinical manifestations of COVID-19 and were diagnosed by reverse transcription PCR (RT-PCR). Genomic DNA was extracted from peripheral blood and saliva samples. ACE insertion/deletion polymorphism was evaluated by the high-resolution melting method; ACE single-nucleotide polymorphism (SNP) (rs4344) and ACE2 SNPs (rs2285666 and rs2074192) were genotyped using TaqMan probes. We assessed the association of ACE and ACE2 polymorphisms with disease severity using logistic regression analysis adjusted by age, sex, hypertension, type 2 diabetes, and obesity. The severity of the illness in our study population was divided as 31% mild, 26% severe, and 43% critical illness; additionally, 18% of individuals died, of whom 54% were male. Our results showed in the codominant model a contribution of ACE2 gene rs2285666 T/T genotype to critical outcome [odds ratio (OR) = 1.83; 95%CI = 1.01–3.29; p = 0.04] and to require oxygen supplementation (OR = 1.76; 95%CI = 1.01–3.04; p = 0.04), in addition to a strong association of the T allele of this variant to develop critical illness in male individuals (OR = 1.81; 95%CI = 1.10–2.98; p = 0.02). We suggest that the T allele of rs2285666 represents a risk factor for severe and critical outcomes of COVID-19, especially for men, regardless of age, hypertension, obesity, and type 2 diabetes.
Several studies suggest an important role of Interleukin-27 in the development of atherosclerosis. The aim of this study was to establish whether the IL-27p28 gene polymorphisms are associated with premature coronary artery disease and/or other cardiovascular risk factors. Four IL-27p28 gene polymorphisms were selected and genotyped in 1162 premature coronary artery disease cases and 1107 controls. rs26528 T and rs40837 A alleles were significantly associated with a lower risk of premature coronary artery disease under different inheritance models (Pdominant = 0.046; Pover-dominant = 0.002; Pco-dominant1 = 0.007 for rs26528T; Pover-dominant = 0.008 and Pco-dominant1 = 0.031 for rs40837). The rs40837 A allele was also associated with a lower risk of insulin resistance, in cases (Pover-dominant = 0.037) and controls (Padditive = 0.008; Pdominant = 0.047; Precessive = 0.014; Pco-dominant2 = 0.006), while the rs26528 T allele was associated with a lower risk of insulin resistance only in the control group (Precessive = 0.016; Pco-dominant2 = 0.021). Interleukin-27 plasma levels were measured in 450 controls and 450 cases, and were significantly higher in cases compared to controls (P = 0.004). However, Interleukin-27 plasma levels were not associated with IL-27p28 polymorphisms. Luciferase assays showed that co-transfection of the rs40837 A allele and miR-379-5p significantly decreased luciferase gene expression. Our study shows for the first time, that IL-27p28 gene polymorphisms are associated with premature coronary artery disease and with some metabolic parameters. The rs40837 A allele in presence of miR-379-5p significantly decreased luciferase gene expression.
Anemia represents a global health problem that negatively impacts quality of life in elderly population; however, its impact on the geriatric syndrome of frailty is unclear. We examined the prevalence of anemia among elderly and sought a relationship between hemoglobin and the phenotype of frailty. Baseline hemoglobin quintiles and anemia were assessed in relation to frailty status in a prospective study with 1,933 older community-dwelling adults enrolled in the Study on Aging and Dementia in Mexico (SADEM). Logistic regression was used to model the relationship between frailty and Hb, adjusting for risk factors of frailty, sociodemographic data, cognitive decline, chronic diseases, and some risky habits. Prevalence of frailty was 8.3 %. Frailty risk was highest at the lowest hemoglobin quintile (<14.3 g/dL for men; <13.3 g/dL for women), and 160 (8.3 %) were anemic (<13 g/dL for men; <12 g/dL for women). The relationship between frailty and Hb levels, adjusted for age and sex, observed in the first and fifth quintiles, compared with the fourth quintile, were 1.53 (95 % confidence interval (CI), 1.46-1.60) and 1.05 (95 % CI, 1.01-1.15). After multivariate adjustment, the odds ratios (ORs) were 1.23 (95 % CI, 1.17-1.13) and 1.06 (95 % CI, 1.01-1.11). The association was not diminished by risk factors for frailty (body mass index (BMI), comorbidity, cognitive decline, smoking, alcohol consumption, etc.). In community-dwelling older adults, low hemoglobin concentrations and anemia were independently associated with increased frailty risk. This suggests that mild anemia and low Hb levels are independent, modifiable risk factors for frailty.
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