Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 91
Filtrar
1.
Biomolecules ; 14(4)2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38672478

RESUMEN

This scientific study employs the Taylor dispersion technique for diffusion measurements to investigate the interaction between sulfamerazine (NaSMR) and macromolecular cyclodextrins (ß-CD and HP-ß-CD). The results reveal that the presence of ß-CD influences the diffusion of the solution component, NaSMR, indicating a counterflow of this drug due to solute interaction. However, diffusion data indicate no inclusion of NaSMR within the sterically hindered HP-ß-CD cavity. Additionally, toxicity tests were conducted, including pollen germination (Actinidia deliciosa) and growth curve assays in BY-2 cells. The pollen germination tests demonstrate a reduction in sulfamerazine toxicity, suggesting potential applications for this antimicrobial agent with diminished adverse effects. This comprehensive investigation contributes to a deeper understanding of sulfamerazine-cyclodextrin interactions and their implications for pharmaceutical and biological systems.


Asunto(s)
Sulfamerazina , Sulfamerazina/química , Difusión , Ciclodextrinas/química , Pruebas de Toxicidad , beta-Ciclodextrinas/química , 2-Hidroxipropil-beta-Ciclodextrina/química
2.
Int J Mol Sci ; 25(8)2024 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-38673912

RESUMEN

In this work, we propose a comprehensive experimental study of the diffusion of nickel ions in combination with different cyclodextrins as carrier molecules for enhanced solubility and facilitated transport. For this, ternary mutual diffusion coefficients measured by Taylor dispersion method are reported for aqueous solutions containing nickel salts and different cyclodextrins (that is, α-CD, ß-CD, and γ-CD) at 298.15 K. A combination of Taylor dispersion and other methods, such as UV-vis spectroscopy, will be used to obtain complementary information on these systems. The determination of the physicochemical properties of these salts with CDs in aqueous solution provides information that allows us to understand solute-solvent interactions, and gives a significant contribution to understanding the mechanisms underlying diffusional transport in aqueous solutions, and, consequently, to mitigating the potential toxicity associated with these metal ions. For example, using mutual diffusion data, it is possible to estimate the number of moles of each ion transported per mole of the cyclodextrin driven by its own concentration gradient.


Asunto(s)
Ciclodextrinas , Níquel , Níquel/química , Ciclodextrinas/química , Difusión , Solubilidad , Iones/química
3.
Osteoporos Int ; 35(5): 819-830, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38267666

RESUMEN

We ascertained the fracture risk factors stratified by vertebral and non-vertebral sites in rheumatoid arthritis (RA) females. Bone/muscle features, but not disease activity, were the main markers for fractures in this long-standing RA population: low trabecular bone score (TBS) for vertebral fracture and decreased appendicular muscle mass for non-vertebral fracture. PURPOSE: To assess risk factors for fractures, including clinical, laboratory and dual energy X-ray absorptiometry (DXA) parameters (bone mass, trabecular bone score-TBS, muscle mass) in women with established rheumatoid arthritis (RA). METHODS: Three hundred females with RA (ACR, 2010) were studied. Clinical data were obtained by questionnaire and disease activity by composite indices (DAS28, CDAI, SDAI), C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR). Bone mineral density (BMD), TBS, body composition and Vertebral Fracture Assessment (VFA) were performed by DXA. Logistic regression models were constructed to identify factors independently associated with vertebral (VF) and non-vertebral fractures (NVF), separately. RESULTS: Through rigorous eligibility criteria, a total of 265 women were yielded for final data analysis (median age, 55 [22-86] years; mean disease duration, 16.2 years). Prevalence of VF and NVF were 30.6% and 17.4%, respectively. In multivariate analyzes, TBS (OR = 1.6, 95%CI = 1.09-2.36, p = 0.017), CRP (OR = 1.54, 95%CI = 1.15-2.08, p = 0.004), and parathormone (OR = 1.24, 95%CI = 1.05-1.45, p = 0.009) were risk factors for VF, whereas low appendicular muscle mass (OR = 2.71; 95%CI = 1.01-7,28; p = 0.048), body mass index (BMI) (OR = 0.90, 95%CI = 0.82-0.99; p = 0.025), ESR (OR = 1.18, 95%CI = 1.01-1,38, p = 0,038) and hip BMD (OR = 1.82, 95%CI = 1.10-3.03, p = 0.02) were associated with NVF. CONCLUSION: In women with long-term RA, markers of fractures differed between distinct skeletal sites (vertebral and non-vertebral). The magnitude of association of bone/muscle parameters with fracture (TBS for VF and appendicular muscle mass for NVF) was greater than that of the association between RA activity and fracture. TBS seems to have greater discriminative power than BMD to identify subjects with VF in long-standing RA.


Asunto(s)
Artritis Reumatoide , Fracturas Osteoporóticas , Fracturas de la Columna Vertebral , Humanos , Femenino , Persona de Mediana Edad , Fracturas de la Columna Vertebral/epidemiología , Hueso Esponjoso/diagnóstico por imagen , Vértebras Lumbares/diagnóstico por imagen , Densidad Ósea/fisiología , Absorciometría de Fotón , Factores de Riesgo , Artritis Reumatoide/complicaciones , Fracturas Osteoporóticas/etiología , Fracturas Osteoporóticas/complicaciones
4.
Rheumatology (Oxford) ; 63(2): 456-465, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-37216912

RESUMEN

OBJECTIVES: To test the association of use of antimalarials with the overall safety of treatment in RA patients receiving one or multiple courses of biologic (b)DMARDs or a Janus kinase inhibitor (JAKi). METHODS: BiobadaBrasil is a multicentric registry-based cohort study of Brazilian patients with rheumatic diseases starting their first bDMARD or JAKi. The present analysis includes RA patients recruited from January 2009 to October 2019, followed up over one or multiple (up to six) courses of treatment (latest date, 19 November 2019). The primary outcome was the incidence of serious adverse events (SAEs). Total and system-specific adverse events (AEs) and treatment interruption served as secondary outcomes. Negative binomial regression with generalized estimating equations (to estimate multivariate incidence rate ratios, mIRR) and frailty Cox proportional hazards models were used for statistical analyses. RESULTS: The number of patients enrolled was 1316 (2335 treatment courses, 6711 patient-years [PY]; 1254.5 PY on antimalarials). The overall incidence of SAEs was 9.2/100 PY. Antimalarials were associated with reduced risk of SAEs (mIRR: 0.49; 95% CI: 0.36, 0.68; P < 0.001), total AEs (0.68; 95% CI: 0.56, 0.81; P < 0.001), serious infections (0.53; 95% CI: 0.34, 0.84; P = 0.007) and total hepatic AEs (0.21; 95% CI: 0.05, 0.85; P = 0.028). Antimalarials were also related to better survival of treatment course (P = 0.003). There was no significant increase in the risk of cardiovascular AEs. CONCLUSION: Among RA patients on treatment with bDMARDs or JAKi, concomitant use of antimalarials was associated with reduced the incidence of serious and total AEs and with longer treatment course survival.


Asunto(s)
Antimaláricos , Antirreumáticos , Artritis Reumatoide , Productos Biológicos , Inhibidores de las Cinasas Janus , Humanos , Inhibidores de las Cinasas Janus/efectos adversos , Antimaláricos/efectos adversos , Estudios de Cohortes , Artritis Reumatoide/epidemiología , Antirreumáticos/efectos adversos , Productos Biológicos/uso terapéutico
5.
Biomolecules ; 13(7)2023 06 29.
Artículo en Inglés | MEDLINE | ID: mdl-37509092

RESUMEN

This Special Issue shows new strategies for the controlled release of drugs using cyclodextrins as carriers [...].


Asunto(s)
Ciclodextrinas , Ciclodextrinas/farmacología , Portadores de Fármacos , Liberación de Fármacos , Preparaciones de Acción Retardada
6.
Foods ; 12(13)2023 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-37444197

RESUMEN

As an alternative to commercial whole egg thermal pasteurization (TP), the sequential combination of moderate pressure (MP) and/or ultrasound (US) pre-treatments prior to a shorter TP was evaluated. The use of US alone or in combination with MP or TP resulted in an inactivation that was far from that of commercial TP. Nevertheless, when these three technologies were combined (MP-US-TP, 160 MPa/5 min-50% amplitude/1 min-60 °C/1.75 min), a safety level comparable to that of commercial TP was established. This was likely due to a decrease in the thermal resistance of Salmonella Senftenberg 775/W caused by MP and US pre-treatments. Regarding liquid whole egg (LWE) properties, using raw LWE as a reference, TP and MP treatments each decreased protein solubility (7-12%), which was accompanied by a viscosity increment (41-59%), whereas the US-only and MP-US-TP treatments improved protein solubility (about 4%) and reduced viscosity (about 34%). On average, all treatments lowered the emulsifying properties of LWE by 35-63%, with the MP-US-TP treatment having a more dramatic impact than commercial TP. In addition, the US-only, MP-only, and MP-US-TP treatments had the greatest impact on the volatile profile of LWE, lowering the concentration of the total volatile components. In comparison to commercial TP, LWE treated with MP-US-TP exhibited greater protein solubility (19%), lower viscosity (56%), and comparable emulsifying stability, but with a decreased emulsifying capacity (39%) and a lower total volatile compounds content (77%). Considering that a combined treatment (MP-US-TP) is lethally equivalent to commercial TP, but the latter better retained the quality properties of raw LWE, including volatiles, the application of MP followed by US pre-treatments before a shorter TP did not demonstrate significant advantages on quality parameters in comparison to commercial TP.

7.
J Phys Act Health ; 20(10): 980-983, 2023 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-37290768

RESUMEN

AIM: To investigate the association between physical activity and immunogenicity among SARS-CoV-2 seropositive patients with autoimmune rheumatic diseases prior to and following a 2-dose schedule of CoronaVac (Sinovac inactivated vaccine). METHODS: This was a prospective cohort study within an open-label, single-arm, phase 4 vaccination trial conducted in Sao Paulo, Brazil. In this substudy, only SARS-CoV-2 seropositive patients were included. Immunogenicity was assessed by seroconversion rates of total anti-SARS-CoV-2 S1/S2 immunoglobulin G (IgG), geometric mean titers of anti-S1/S2 IgG, frequency of positive neutralizing antibodies, and neutralizing activity before and after vaccination. Physical activity was assessed through a questionnaire. Model-based analyses were performed controlling for age (<60 or ≥60 y), sex, body mass index (<25, 25-30, and >30 kg/m2), and use of prednisone, immunosuppressants, and biologics. RESULTS: A total of 180 seropositive autoimmune rheumatic disease patients were included. There was no association between physical activity and immunogenicity before and after vaccination. CONCLUSIONS: This study suggests that the positive association between physical activity and greater antibody responses seen in immunocompromised individuals following vaccination is overridden by previous SARS-CoV-2 infection, and does not extend to natural immunity.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , Ejercicio Físico , COVID-19/prevención & control , Estudios Prospectivos , Brasil/epidemiología , Vacunación , Inmunoglobulina G
8.
J Phys Act Health ; 20(4): 311-316, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-36870351

RESUMEN

BACKGROUND: Physical activity associates with improved immunogenicity following a 2-dose schedule of CoronaVac (Sinovac's inactivated SARS-CoV-2 vaccine) in patients with autoimmune rheumatic diseases (ARD). This study evaluates whether physical activity impacts vaccine-induced antibody responses to a booster dose in this population. METHODS: This was a phase-4 trial conducted in São Paulo, Brazil. Patients with ARD underwent a 3-dose schedule of CoronaVac. One month after the booster, we assessed seroconversion rates of anti-SARS-CoV-2 S1/S2 IgG, geometric mean titers of anti-S1/S2 IgG, frequency of positive neutralizing antibodies, and neutralizing activity. Physical activity was assessed through questionnaire. RESULTS: Physically active (n = 362) and inactive (n = 278) patients were comparable for most characteristics; however, physically active patients were younger (P < .01) and had a lower frequency of chronic inflammatory arthritis (P < .01). Adjusted models showed that physically active patients had ∼2 times odds of seroconversion rates (OR: 2.09; 95% confidence interval, 1.22 to 3.61), ∼22% greater geometric mean titers of anti-S1/S2 IgG (22.09%; 95% confidence interval, 3.91 to 65.60), and ∼7% greater neutralizing activity (6.76%; 95% confidence interval, 2.80 to 10.72) than inactive patients. CONCLUSIONS: Patients with ARD who are physically active have greater odds of experiencing better immunogenicity to a booster dose of CoronaVac. These results support the recommendation of physical activity to improve vaccination responses, particularly for immunocompromised individuals.


Asunto(s)
COVID-19 , Enfermedades Reumáticas , Humanos , Formación de Anticuerpos , Brasil , COVID-19/prevención & control , Vacunas contra la COVID-19 , Ejercicio Físico , Inmunoglobulina G , SARS-CoV-2
9.
Int J Mol Sci ; 24(3)2023 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-36769218

RESUMEN

Knowledge of mass transport parameters, diffusion, and viscosity of hyaluronic acid (HA) in the presence of cyclodextrins is of considerable importance for areas such as food packaging and drug delivery, among others. Despite a number of studies investigating the functionalization of HA or the corresponding sodium salt by cyclodextrins, only a few studies have reported the effect of cyclodextrins on the mass transport of HA in the presence of these oligosaccharides. Here, we report the tracer binary and ternary interdiffusion coefficients of sodium hyaluronate (NaHy) in water and aqueous ß-cyclodextrin solutions. The diffusion behavior of sodium hyaluronate was dependent on the reduced viscosity of NaHy, which, in turn, presented a concave dependence on concentration, with a minimum at approximately 2.5 g dm-3. The significant decrease in the limiting diffusion coefficient of NaHy (at most 45%) at NaHy concentrations below 1 g dm-3 in the presence of ß-cyclodextrin, taking water as the reference, allowed us to conclude that NaHy strongly interacted with the cyclodextrin.


Asunto(s)
Ciclodextrinas , beta-Ciclodextrinas , Ácido Hialurónico , Difusión , Agua
10.
Int J Mol Sci ; 24(4)2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36835327

RESUMEN

The interaction between sodium salicylate (NaSal) and the two macrocycles 5,11,17,23-tetrakissulfonatomethylene-2,8,14,20-tetra(ethyl)resorcinarene (Na4EtRA) and ß-cyclodextrin (ß-CD) has been studied by the determination of ternary mutual diffusion coefficients, and spectroscopic and computational techniques. The results obtained by the Job method suggest that the complex formation is given in a 1:1 ratio for all systems. The mutual diffusion coefficients and the computational experiments have shown that the ß-CD-NaSal system presents an inclusion process, whereas the Na4EtRA-NaSal system forms an outer-side complex. This fact is also in line with the results obtained from the computational experiments, where the calculated solvation free energy has been found to be more negative for the Na4EtRA-NaSal complex because of the partial entry of the drug inside the Na4EtRA cavity.


Asunto(s)
Salicilato de Sodio , beta-Ciclodextrinas , beta-Ciclodextrinas/química , Resorcinoles
11.
Molecules ; 28(2)2023 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-36677839

RESUMEN

Experimental binary diffusion coefficients for short-chain alcohols in supercritical carbon dioxide were measured using the Taylor dispersion technique in a temperature range of 306.15 K to 331.15 K and along the 10.5 MPa isobar. The obtained diffusion coefficients were in the order of 10-8 m2 s-1. The dependence of D on temperature and solvent density was examined together with the influence of molecular size. Some classic correlation models based on the hydrodynamic and free volume theory were used to estimate the diffusion coefficients in supercritical carbon dioxide. Predicted values were generally overestimated in comparison with experimental ones and correlations were shown to be valid only in high-density regions.

12.
Clinics (Sao Paulo) ; 78: 100150, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36529052

RESUMEN

OBJECTIVE: To evaluate inactivated CoronaVac prime vaccination, antibody decay, booster dose, and safety in ANCA-Associated Vasculitis (AAV) patients. METHODS: Fifty-three AAV patients and 106 Controls (CG) received CoronaVac on days: D0 (first dose), D28(second dose), and D210 (booster dose, 32 AAV: 32 CG). The primary outcome was immunogenicity after the second vaccine dose (day 69) assessed by Seroconversion Rates (SC) of anti-SARS-CoV-2 S1/S2 IgG and Neutralizing Antibodies (NAb). Secondary outcomes were safety, immunogenicity (D28/D240), 6-months antibody decay (D210) and the booster dose response (D240). RESULTS: At D69 SC (65.1% vs. 96.8%, p = 0.0001), GMT (21.3 UA/mL vs. 67.7 UA/mL, p < 0.001) and NAb- positivity (53.7% vs. 80.6%, p = 0.001) were moderate but lower in naïve-AAV patients than CG. Patients without SC used more often IS (93.3% vs. 53.3%, p = 0.015), mycophenolate mofetil (20% vs. 0%, p = 0.037) and prednisone (60.0% vs. 28.6%, p = 0.057) than seroconverted. NAb negativity in AAV patients was associated with prednisone treatment (57.9% vs. 18.2%, p = 0.015) and IS (84.2% vs. 55.0%, p = 0.046). Logistic regression analysis models showed that only prednisone was associated with lower seroconversion (OR = 0.2, 0,95% CI 0.05‒0.86, p = 0.030) and with lower NAb positivity (OR = 0.2, 0,95% CI 0.05‒0.88, p = 0.034). After six months (D69‒D210) a decrease in IgG positivity occurred in 32 AAV patients (15.7%, p = 0.074) and 32 CG (18.7%, p = 0.041). For the NAb positivity, the 6-month decrease was not significant (p = 0.114) whereas a major reduction occurred for CG (p < 0.001). A booster dose (D240) resulted in an increment in IgG-positivity (21.9%, p = 0.023) and NAb-positivity (34.4%, p = 0.006) in AAV patients. No moderate/severe adverse events attributable to the vaccine were observed. CONCLUSION: This study provides novel data on the excellent safety and moderate immunogenicity of CoronaVac in AAV patients. A six-month mild antibody waning was observed with a good response to the booster dose, although levels remained lower than CG (CoronavRheum-NCT04754698).


Asunto(s)
Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos , COVID-19 , Humanos , Anticuerpos Antivirales , Inmunoglobulina G , Prednisona
13.
Joint Bone Spine ; 90(1): 105464, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36150668

RESUMEN

OBJECTIVES: To evaluate humoral responses to three doses of the inactivated SARS-CoV-2 vaccine (CoronaVac) in patients with spondyloarthritis (SpA) and the effect of therapy, compared with a control group (CG). METHODS: Prospective cohort of axial SpA/psoriatic arthritis patients and age/sex-balanced CG from the CoronavRheum phase 4 trial (NCT04754698). CoronaVac was given in two doses (28-days interval) with a booster at day 210. Blood samples were collected in the days 0/28 (D28)/69 (D69) and 240 (D240) to evaluate anti-SARS-CoV-2 IgG seropositivity (SP) and neutralising antibodies (NAb). RESULTS: One hundred and ninety-four SpA patients were enrolled and 183 patients were age/sex-balanced with 183 CG. At D69, SpA patients showed a high SP (80.2% vs. 95.7%, P<0.001) and moderate NAb positivity (61.6% vs. 82.7%, P<0.001), but lower than CG. In patients, older age prednisone (P<0.001), methotrexate (MTX) (P<0.001) and TNF inhibitors (TNFi) (P<0.001) were independently associated with lower SP, while Caucasian ethnicity (P<0.05) and prednisone (P<0.01) were associated with diminished NAb. In contrast, sulfasalazine (SSZ) use was associated with NAb presence (P<0.05). In monotherapy, only TNFi was also associated with absence of SP (P<0.05). Further comparison with CG revealed that TNFi and/or MTX negatively impacted SP/NAb (P<0.05). In contrast, patients under SSZ monotherapy achieved 100% SP (P>0.999) and 83.3% NAb positivity (P>0.999). SSZ+TNFi combination resulted in a similar response than CG [SP (P=0.153) and NAb (P=0.715)]. After third dose (D69-D240), a major increment occurred for SP (81.3% to 93.1%, P<0.001) and NAb (63.2% to 86.1%, P<0.001), but still lower than CG (P<0.05), and only TNFi impaired both SP (P=0.016)/NAb (P=0.002). CONCLUSIONS: We provided novel data demonstrating that TNFi attenuates immunogenicity in SpA patients while SSZ has a positive impact on vaccine antibody production. We also confirmed that MTX in combination with TNFi had a major negative impact in vaccine humoral response (CoronavRheum clinicaltrials.gov #NCT04754698).


Asunto(s)
Antirreumáticos , Artritis Psoriásica , Espondiloartritis Axial , COVID-19 , Espondiloartritis , Humanos , Antirreumáticos/uso terapéutico , Artritis Psoriásica/tratamiento farmacológico , Vacunas contra la COVID-19/uso terapéutico , Metotrexato/uso terapéutico , Prednisona/uso terapéutico , Estudios Prospectivos , SARS-CoV-2 , Espondiloartritis/tratamiento farmacológico , Sulfasalazina/uso terapéutico , Resultado del Tratamiento , Inhibidores del Factor de Necrosis Tumoral/uso terapéutico , Factor de Necrosis Tumoral alfa/uso terapéutico , Masculino , Femenino
14.
Clinics ; 78: 100150, 2023. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1421262

RESUMEN

Abstract Objective: To evaluate inactivated CoronaVac prime vaccination, antibody decay, booster dose, and safety in ANCA-Associated Vasculitis (AAV) patients. Methods: Fifty-three AAV patients and 106 Controls (CG) received CoronaVac on days: D0 (first dose), D28(second dose), and D210 (booster dose, 32 AAV: 32 CG). The primary outcome was immunogenicity after the second vaccine dose (day 69) assessed by Seroconversion Rates (SC) of anti-SARS-CoV-2 S1/S2 IgG and Neutralizing Antibodies (NAb). Secondary outcomes were safety, immunogenicity (D28/D240), 6-months antibody decay (D210) and the booster dose response (D240). Results: At D69 SC (65.1% vs. 96.8%, p = 0.0001), GMT (21.3 UA/mL vs. 67.7 UA/mL, p < 0.001) and NAb- positivity (53.7% vs. 80.6%, p = 0.001) were moderate but lower in naïve-AAV patients than CG. Patients without SC used more often IS (93.3% vs. 53.3%, p = 0.015), mycophenolate mofetil (20% vs. 0%, p = 0.037) and prednisone (60.0% vs. 28.6%, p = 0.057) than seroconverted. NAb negativity in AAV patients was associated with prednisone treatment (57.9% vs. 18.2%, p = 0.015) and IS (84.2% vs. 55.0%, p = 0.046). Logistic regression analysis models showed that only prednisone was associated with lower seroconversion (OR = 0.2, 0,95% CI 0.05-0.86, p = 0.030) and with lower NAb positivity (OR = 0.2, 0,95% CI 0.05-0.88, p = 0.034). After six months (D69-D210) a decrease in IgG positivity occurred in 32 AAV patients (15.7%, p = 0.074) and 32 CG (18.7%, p = 0.041). For the NAb positivity, the 6-month decrease was not significant (p = 0.114) whereas a major reduction occurred for CG (p < 0.001). A booster dose (D240) resulted in an increment in IgG-positivity (21.9%, p = 0.023) and NAb-positivity (34.4%, p = 0.006) in AAV patients. No moderate/severe adverse events attributable to the vaccine were observed. Conclusion: This study provides novel data on the excellent safety and moderate immunogenicity of CoronaVac in AAV patients. A six-month mild antibody waning was observed with a good response to the booster dose, although levels remained lower than CG (CoronavRheum-NCT04754698).

15.
Int J Mol Sci ; 23(24)2022 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-36555523

RESUMEN

It is well known that polar organic compounds, such as alcohols and polyols, exert an appreciable influence on water structure and thus have important effects on surfactant micellization. These substances are often used to modify the properties of surfactants in aqueous solutions, increasing the practical applications they have in diverse industries. In this work, the critical micelle concentration (CMC) of decyltrimethylammonium bromide (C10TAB) in water and in 1,2-propanediol aqueous solutions was determined from both sound velocity and surface tension measurements as a function of surfactant concentration in the temperature range of (293.15 to 308.15) K. The critical micelle concentration of the surfactant increases as the concentration of 1,2-propanediol becomes higher, while the effect on temperature does not show important changes within the range considered. At the selected temperatures, the standard thermodynamic parameters of micellization suggests that the addition of 1,2-propanediol makes the micellization process less favorable. Thermodynamic analysis suggests that the micelle formation of C10TAB is an entropy-driven process at the temperatures considered in this study.


Asunto(s)
Micelas , Propilenglicol , Temperatura , Tensoactivos/química , Agua/química
18.
Nat Commun ; 13(1): 5801, 2022 10 03.
Artículo en Inglés | MEDLINE | ID: mdl-36192386

RESUMEN

The determination of durability and vaccine-associated protection is essential for booster doses strategies, however data on the stability of SARS-CoV-2 immunity are scarce. Here we assess anti-SARS-CoV-2 immunogenicity decay and incident cases six months after the 2nd dose of Sinovac-CoronaVac inactivated vaccine (D210) in 828 autoimmune rheumatic diseases patients compared with 207 age/sex-balanced control individuals. The primary outcome is the presence of anti-S1/S2 SARS-CoV-2 IgG at 6 months compared to 6 weeks after 2nd vaccine dose for decay evaluation. Secondary outcomes are presence of neutralizing antibodies, percent inhibition by neutralizing, geometric mean titers and cumulative incident cases at 6 months after 2nd dose. Anti-S1/S2 IgG positivity and titers reduce to 23.8% and 38% in patients (p < 0.001) during the six-month follow up and 20% and 51% in controls (p < 0.001), respectively. Neutralizing antibodies positivity and percent inhibition declines 41% and 54% in patients (p < 0.001) and 39.7% and 47% in controls (p < 0.001). Multivariate logistic regression analysis show males (OR = 0.56;95% CI0.40-0.79), prednisone (OR = 0.56; 95% CI0.41-0.76), anti-TNF (OR = 0.66;95% CI0.45-0.96), abatacept (OR = 0.29; 95% CI0.15-0.56) and rituximab (OR = 0.32;95% CI0.11-0.90) associate with a substantial reduction in IgG response at day 210 in patients. Although cellular immunity was not assessed, a decrease of COVID-19 cases (from 27.5 to 8.1/100 person-years; p < 0.001) is observed despite the concomitant emergence and spread of the Delta variant. Altogether we show a reduction in immunity 6-months of Sinovac-CoronaVac 2nd dose, particularly in males and those under immunosuppressives therapies, without a concomitant rise in COVID-19 cases. (CoronavRheum clinicaltrials.gov:NCT04754698).


Asunto(s)
COVID-19 , Enfermedades Reumáticas , Vacunas Virales , Abatacept , Anticuerpos Neutralizantes , Anticuerpos Antivirales , COVID-19/epidemiología , COVID-19/prevención & control , Vacunas contra la COVID-19 , Humanos , Inmunoglobulina G , Incidencia , Masculino , Prednisona , Enfermedades Reumáticas/tratamiento farmacológico , Enfermedades Reumáticas/epidemiología , Rituximab/uso terapéutico , SARS-CoV-2 , Inhibidores del Factor de Necrosis Tumoral , Vacunas de Productos Inactivados
19.
Biomolecules ; 12(7)2022 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-35883503

RESUMEN

In this study, diffusion coefficients of ammonium vanadate at tracer concentrations in artificial saliva with and without sodium fluoride, at different pH values, were measured using an experimental model based on the Taylor dispersion technique. Ternary mutual diffusion coefficients (D11, D22, D12, and D21) for four aqueous systems {NH4VO3 (component 1) + ß-cyclodextrin (ß-CD) (component 2),} {NH4VO3 (component 1) + ß-cyclodextrin (HP-ß-CD) (component 2)}, {NH4VO3 (component 1) + sodium dodecyl sulphate (SDS) (component 2)} and {NH4VO3 (component 1) + sodium hyaluronate (NaHy) (component 2)} at 25.00 °C were also measured by using the same technique. These data showed that diffusion of ammonium vanadate was strongly affected in all aqueous media studied. Furthermore, a significant coupled diffusion of this salt and ß-CD was observed through the non-zero values of the cross-diffusion coefficients, D12, allowing us to conclude that there is a strong interaction between these two components. This finding is very promising considering the removal, from the oral cavity, of vanadium resulting from tribocorrosion of Ti-6Al-4V prosthetic devices.


Asunto(s)
Compuestos de Amonio , beta-Ciclodextrinas , Aleaciones , Iones , Boca , Antisépticos Bucales , Saliva Artificial/química , Titanio/química , Vanadatos , Vanadio
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA