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1.
Molecules ; 29(16)2024 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-39202853

RESUMEN

Carbon nitrides can form coordination compounds or metallic oxides in the presence of transition metals, depending on the reaction conditions. By adjusting the pH to basic levels for mild synthesis with metals, composites like g-C3N4-M(OH)x (where M represents metals) were obtained for nickel (II) and manganese (II), while copper (II) yielded coordination compounds such as Cu-g-C3N4. These materials underwent spectroscopic and electrochemical characterization, revealing their photocatalytic potential to generate superoxide anion radicals-a feature consistent across all metals. Notably, the copper coordination compound also produced significant hydroxyl radicals. Leveraging this catalytic advantage, with band gap energy in the visible region, all compounds were activated to disinfect E. coli bacteria, achieving total disinfection with Cu-g-C3N4. The textural properties influence the catalytic performance, with copper's stabilization as a coordination compound enabling more efficient activity compared to the other metals. Additionally, the determination of radicals generated under light in the presence of dicloxacillin supported the proposed mechanism and highlighted the potential for degrading organic molecules with this new material, alongside its disinfectant properties.

2.
Foods ; 13(15)2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39123536

RESUMEN

This project studied the use of lentil protein (LP) and quinoa protein (QP) in their native and modified states as carrier material in the encapsulation process by the ionic gelation technique of annatto seed extract. Soy protein (SP) was used as a model of carrier material and encapsulated bioactive compounds, respectively. The plant proteins were modified by enzymatic hydrolysis, N acylation, and N-cationization to improve their encapsulating properties. Additionally, the secondary structure, differential scanning calorimetry (DSC), solubility as a function of pH, isoelectric point (pI), molecular weight (MW), the content of free thiol groups (SH), the absorption capacity of water (WHC) and fat (FAC), emulsifier activity (EAI), emulsifier stability (ESI), and gelation temperature (Tg) were assessed on proteins in native and modified states. The results obtained demonstrated that in a native state, LP (80.52% and 63.82%) showed higher encapsulation efficiency than QP (73.63% and 45.77%), both for the hydrophilic dye and for the annatto extract. Structural modifications on proteins improve some functional properties, such as solubility, WHC, FAC, EAI, and ESI. However, enzymatic hydrolysis on the proteins decreased the gels' formation, the annatto extract's encapsulated efficiency, and the hydrophilic dye by the ionic gelation method. On the other hand, the modifications of N-acylation and N-cationization increased but did not generate statistically significant differences (p-value > 0.05) in the encapsulation efficiency of both the annatto extract and the hydrophilic dye compared to those obtained with native proteins. This research contributes to understanding how plant proteins (LP and QP) can be modified to enhance their encapsulating and solubility properties. The better encapsulation of bioactive compounds (like annatto extract) can improve product self-life, potentially benefiting the development of functional ingredients for the food industry.

3.
PLoS One ; 18(5): e0285765, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37172065

RESUMEN

OBJECTIVES: To measure housing assistance and homelessness among persons living with HIV (PLWH) and their association with health. METHODS: Exposure categories were: experiencing homelessness (per emergency shelter use or self-report), receiving housing assistance (per housing subsidy) without homelessness, or neither homelessness nor receiving housing assistance. Outcomes were: engagement (≥1 visit) and retention (≥2 visits ≥90 days apart) in HIV-related medical care and one-time (latest viral load) and durable (≥1 viral load test, all suppressed) HIV viral suppression (<200 copies/mL). Among PLWH in New York City (NYC), we calculated and conducted modified Poisson regressions of the four outcomes according to exposure category. RESULTS: During 2018, 45% of NYC's 84,053 PLWH received housing assistance, and 8% experienced homelessness. Relative to homelessness, receipt of assistance without homelessness was associated with 3-7% higher adjusted relative risk (ARR) of engagement and retention in care and 31-64% higher ARR of one-time and durable viral suppression. Relative to not receiving assistance, receipt of assistance without homelessness was associated with 6-18% higher ARR of care and 2-5% lower ARR of viral suppression. CONCLUSIONS: Programs promoting housing stability may support HIV care and viral suppression, particularly if preventing homelessness. These may help improve HIV care and suppression rates.


Asunto(s)
Infecciones por VIH , Personas con Mala Vivienda , Humanos , Vivienda , Vivienda Popular , Ciudad de Nueva York/epidemiología , Infecciones por VIH/epidemiología , Infecciones por VIH/terapia , Problemas Sociales , Carga Viral
4.
Foods ; 11(19)2022 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-36230192

RESUMEN

Given consumer trends propelling a movement toward using plant protein in the food industry and searching for alternative protein ingredients by the industry, this study aimed to assess the influence of factors such as protein concentration, medium pH, and the presence of a divalent ion (Ca2+) upon the rheological properties such as viscosity change and gel formation of dispersion proteins extracted from quinoa, black beans, and lentils. A solution of each protein was prepared by varying its concentration (2.5%, 5.0%, and 10%), the pH (5.0, 7.0, and 9.0), and the incorporation of calcium chloride (0.0% and 1.0%). Each obtained solution was subjected to rheological tests to determine the parameters: consistency index (K), flow behavior (n), the storage (G') and loss (G'') modules, and the phase shift angle (δ). The results demonstrate that the incorporation of Ca2+, the shift in protein levels, and the decrease in pH modified the rheological behaviors of proteins, which were also influenced by the structural characteristics of each protein studied. However, thermal treatment and protein concentrations caused the most significant impact on proteins' rheological behavior, forming gels independently of other conditions. It was possible to study and interpret the studied proteins' rheological variations according to the environment's conditions.

5.
J Food Sci Technol ; 59(5): 1665-1676, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35531395

RESUMEN

Sonicated protein isolates were recovered from Chenopodium quinua, Phaseoulus vulgaris and Lens culinaris to develop a functional matrix by assessing the physicochemical and functional properties. The plant protein isolates were prepared from powdered materials followed by sonication in alkaline medium using a Box-Behnken design. pH (6-10), a buffer-to-material ratio (5:1 to 15:1) and sonication time (0-20 min) were taken as independent variables, whereas protein yield was taken as the dependent variable. A pH of 9, 20 min treatment, and a buffer-to-material ratio of 5:1 were the optimal extraction conditions for quinoa and black beans, whereas a 1:10 ratio was suitable for lentils. Sonication in alkaline medium caused partial protein unfolding and these isolates; in turn, the molecular weight affected the emulsifying activity and stability. Moreover, sonication had a strong effect on the gelation temperature, emulsifying activity, the water, and oil sorption. Sonication improved protein yield and exposed amino acids such as glutamic acid, aspartic acid, leucine and glycine. In turn, thiol groups were responsible for the increased in gelation temperature. The better gelling property coupled with high emulsifying property of these proteins show potential application as protein emulsifiers in the production of gels, sausages, and pet foods.

6.
Polymers (Basel) ; 14(9)2022 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-35566922

RESUMEN

The addition of polymers in construction is a new tendency and an important step toward the production of structures with better functional properties. This work investigates the addition of polyurea (PU) as a polymeric material in mortars. Polymer mortars were manufactured with the addition of polyurea retained in different sieves (T50 and T100) and different concentrations (2% and 5%). The characterization of the, polyurea (PU)control mortar (PU0%) and manufactured polyurea mortars (PU2%T50, PU5%T50, PU2%T100, and PU5%T100) was conducted by means of morphological analysis, SEM, XRF, TGA, and a compressive strength test of hydraulic mortars. The results show that mortars with polyurea retained in sieve 100 with a particle size of 150 µm exhibit better thermal behavior and a greater resistance to compression with a concentration of 5% polyurea with respect to the other samples. The present work reveals that polyurea retained in sieve 100 can be considered as a polymeric additive for mortars, indicating that it could be a candidate for applications such as construction.

7.
Infection ; 50(5): 1321-1328, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35562568

RESUMEN

PURPOSE: Assess the impact of viral load estimated by cycle threshold (Ct) of reverse transcription real time-polymerase chain reaction (rRT-PCR) and the days from symptoms onset on mortality in hospitalized patients with COVID19. METHODS: Retrospective observational study of 782 patients with a positive rRT-PCR from a nasopharyngeal swab was performed within the first 24 h from admission. Demographic data, clinical manifestations and laboratory parameters were collected. Uni- and multivariate analyses were performed to identify factors associated with mortality at 60 days. RESULTS: Ct was divided into three groups and the mortality rate decreased from 27.3 to 20.7% and 9.8% for Ct values of ≤ 20, 21-25 and > 25, respectively (P = 0.0001). The multivariate analysis identified as predictors of mortality, a Ct value < 20 (OR 3.13, CI 95% 1.38-7.10), between 21-25 (OR 2.47, CI 95% 1.32-4.64) with respect to a Ct value > 25. Days from symptoms onset is a variable associated with mortality as well (DSOA) ≤ 6 (OR 1.86, CI 95% 1.00-3.46), among other factors. Patients requiring hospital admission within 6 DSOA with a Ct value ≤ 25 had the highest mortality rate (28%). CONCLUSIONS: The inclusion of Ct values and DSOA in the characterization of study populations could be a useful tool to evaluate the efficacy of antivirals.


Asunto(s)
COVID-19 , SARS-CoV-2 , Antivirales , Hospitales , Humanos , Carga Viral
8.
Molecules ; 26(9)2021 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-33921948

RESUMEN

Clove essential oil (CEO) is known for having excellent antioxidant and antimicrobial properties, but the poor stability of its components to light and temperature compromise this activity. The aim of this study is to evaluate the textural, antioxidant, antimicrobial and microstructural properties of matrixes produced with representative natural waxes and CEO. Thus, waxy emulsifiers, such as beeswax, candelilla wax, carnauba wax, and ozokerite wax, were employed to create such matrixes. The thermal, microstructural, textural, wetting, antioxidant, antimicrobial and infrared characteristics of the matrixes were then studied. The diverse chemical composition (long-chain wax esters in carnauba wax and short-chain fatty acids and hydrocarbons in beeswax and ozokerite wax, respectively) explained the differences in wetting, texture, melting, and crystallization characteristics. Crystal forms of these matrix systems varied from grainy, oval, to needle-like shape, but keeping an orthorhombic allomorph. The alignment and reorganization of beeswax and ozokerite wax into needle-like crystals increased the matrix strength and adhesion force compared to those of carnauba and candelilla matrixes, which showed weak strength and grainy morphology. The former two waxes and their matrixes also showed the largest plasticity. These lipidic matrixes show potential use for topical applications having acceptable antioxidant and textural properties.


Asunto(s)
Aceite de Clavo/química , Aceite de Clavo/farmacología , Lípidos/química , Aceites Volátiles/química , Aceites Volátiles/farmacología , Antiinfecciosos/química , Antiinfecciosos/farmacología , Antioxidantes/química , Antioxidantes/farmacología , Fenómenos Químicos , Fenómenos Mecánicos , Estructura Molecular , Espectroscopía Infrarroja por Transformada de Fourier , Relación Estructura-Actividad , Ceras/química , Difracción de Rayos X
9.
Data Brief ; 31: 106014, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32715043

RESUMEN

Traditionally, oil structuring has been conducted merely in vegetable oils. Alternatively, essential oil structuring provides a great opportunity to develop the topical application of these oils without causing allergic contact dermatitis and improving the sensory properties. The thermal, rheological and microstructure data collection of lipidic matrices produced with representative gelators such as carnauba wax, stearic acid, glyceryl monostearate and hydroxyethyl cellulose in lemon essential oil were carried out by DSC, rheology and phase contrast microscopy measurements. This dataset is valuable to researchers interested in characterizing lipidic matrices produced with several gelators, once incorporated in different topical formulations. These data can be used for quality control of topical formulations having several textural features.

10.
Carbohydr Polym ; 243: 116436, 2020 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-32532389

RESUMEN

Methotrexate-loaded phytic acid-chitosan nanoparticles were synthesized by ionic gelation assisted by high-intensity sonication. The nanoparticles were characterized by particle size, polydispersity index, zeta potential (ZP) and encapsulation efficiency. Their physical stability was evaluated at 4 °C and 40 °C, whereas the in-vitro methotrexate release was assessed at pH 7.4. The data were heuristically fit to first-order, Higuchi, Peppas-Sahlin and Korsmeyer-Peppas models of release kinetics. Anticancer activity was evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide (MTT) assay on HT-29 human colon adenocarcinoma cells. Physicochemical analysis showed that the nanoparticles presented positive ZP values, sizes less than <300 nm and low polydispersity, except for systems formed with low amplitude sonication. The nanoparticles exhibited an adequate physical stability and a capability to modify methotrexate release by a non-Fickian mechanism, resulting in a more pronounced cytotoxic effect than the free drug on HT-29 human colon adenocarcinoma cells.


Asunto(s)
Adenocarcinoma/patología , Antineoplásicos/farmacología , Neoplasias del Colon/patología , Portadores de Fármacos/química , Metotrexato/farmacología , Nanopartículas/química , Adenocarcinoma/tratamiento farmacológico , Quitosano/química , Neoplasias del Colon/tratamiento farmacológico , Liberación de Fármacos , Geles , Células HT29 , Humanos , Ácido Fítico/química
11.
Am J Public Health ; 110(7): 1068-1075, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32437285

RESUMEN

Objectives. To evaluate the impact of duration and service category on HIV health outcomes among low-income adults living with HIV and enrolled in a housing program in 2014 to 2017.Methods. We estimated relative risk of engagement in care, viral suppression, and CD4 improvement for 561 consumers at first and second year after enrollment to matched controls through the New York City HIV surveillance registry, by enrollment length (enrolled for more than 1 year or not) and service category (housing placement assistance [HPA], supportive permanent housing [SPH], and rental assistance [REN]).Results. The SPH and REN consumers were enrolled longer and received more services, compared with HPA consumers. Long-term SPH and REN consumers had better engagement in care, viral suppression, and CD4 count than controls at both first and second year after enrollment, but the effect did not grow bigger from year 1 to 2. HPA consumers did not have better outcomes than controls regardless of enrollment length.Conclusions. Longer enrollment with timely housing placement and a higher number and more types of services are associated with better HIV health outcomes for low-income persons living with HIV with unmet housing needs.


Asunto(s)
Infecciones por VIH , Vivienda , Participación del Paciente/estadística & datos numéricos , Evaluación de Programas y Proyectos de Salud , Adulto , Anciano , Recuento de Linfocito CD4/estadística & datos numéricos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Ciudad de Nueva York/epidemiología , Evaluación de Resultado en la Atención de Salud , Pobreza/estadística & datos numéricos , Carga Viral
12.
Antioxidants (Basel) ; 9(4)2020 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-32294926

RESUMEN

This study aimed to assess the thermal stability of the bioactive compounds from annatto seed extract, encapsulated by ionic gelation using quinoa proteins, lentil proteins, soy proteins, and sodium caseinate as carrying materials. The 10.0% aqueous dispersions of the different proteins (carriers) were prepared and mixed with the annatto seed extract. The dispersions were then extruded into a calcium chloride solution to induce the extract encapsulation. The capsules were characterized by encapsulation efficiency, particle size, infrared transmission spectroscopy, confocal microscopy, and scanning electron microscopy (SEM). The antioxidant and antimicrobial activities, the polyphenol compounds, and bixin content from the free and encapsulated extract were assessed once stored for 12 d at different temperatures (4 °C, 25 °C, and 65 °C). The results demonstrated the ability of the proteins to encapsulate the annatto extract with encapsulation efficiencies ranging from 58% to 80%, where the protein structure and amino acid content were the relevant factors to obtain high encapsulation efficiencies. The free extracts stored at 65 °C for 12 d experienced a degradation of bixin and polyphenol compounds, respectively. Conversely, the encapsulated extract had degradations from ~34.00% to ~4.05% for polyphenol compounds and ~20.0% for bixin, respectively. These proteins have a potential encapsulation capacity of annatto extract by ionic gelation.

13.
AIDS Behav ; 24(11): 3252-3263, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32180090

RESUMEN

Among 958 applicants to a supportive housing program for low-income persons living with HIV (PLWH) and mental illness or a substance use disorder, we assessed impacts of housing placement on housing stability, HIV care engagement, and viral suppression. Surveillance and administrative datasets provided medical and residence information, including stable (e.g., rental assistance, supportive housing) and unstable (e.g., emergency shelter) government-subsidized housing. Sequence analysis identified a "quick stable housing" pattern for 67% of persons placed by this program within 2 years, vs. 28% of unplaced. Compared with unplaced persons not achieving stable housing quickly, persons quickly achieving stable housing were more likely to engage in care, whether placed (per Poisson regression, ARR: 1.14;95% CI 1.09-1.20) or unplaced (1.19;1.13-1.25) by this program, and to be virally suppressed, whether placed (1.22;1.03-1.44) or unplaced (1.26, 1.03-1.56) by this program. Housing programs can help homeless PLWH secure stable housing quickly, manage their infection, and prevent transmission.


RESUMEN: Unas 958 personas de bajos recursos y quienes viven con VIH y enfermedades mentales o bien presentan problemas de abuso de sustancias solicitaron a un programa de vivienda complementada con servicios de apoyo. Entre ellas, se evaluó los impactos de la colocación en viviendas sobre la estabilidad en la misma, así como la participación en los cuidados médicos para el VIH, y la supresión de la carga viral. Las bases de datos administrativas y del registro de vigilancia brindaron información médica y domiciliar, incluyendo información sobre vivienda estable (por ejemplo, asistencia de pago de renta a largo plazo, o vivienda complementada con servicios de apoyo) y vivienda inestable (por ejemplo, alojamiento de emergencia temporal) subsidiada por el gobierno. El método "análisis de secuencia" permitió identificar una pauta caracterizada por estabilidad domiciliar conseguida de modo ligero (es decir, de forma oportuna) en el 67% de las personas quienes fueron colocadas por este programa dentro de un lapso de dos años, comparado con 28% de las personas quienes no fueron colocadas. En comparación con las personas quienes no fueron colocadas y no lograron estabilidad de vivienda de modo ligero, las personas quienes lograron estabilidad de vivienda de modo ligero tuvieron una mayor probabilidad de participar en cuidados médicos, ya sea que fueran colocadas (según regresión de Poisson, cociente de riesgo ajustado: 1.14; intervalo de confianza de 95%: 1.09-1.20) o no fueran colocadas (1.19, 1.13-1.25) por este programa, así como de lograr la supresión de la carga viral, ya sea que fueran colocadas (1.22, 1.03-1.44) o no fueran colocadas (1.26, 1.03-1.56) por este programa. Los programas que facilitan la colocación en o el pago de vivienda y apoyo en el mismo pueden ayudar a las personas con VIH y sin hogar obtener vivienda estable de modo ligero, controlar su infección, y prevenir la transmisión.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Personas con Mala Vivienda/psicología , Trastornos Mentales/complicaciones , Asistencia Pública/estadística & datos numéricos , Vivienda Popular/estadística & datos numéricos , Trastornos Relacionados con Sustancias/complicaciones , Adulto , Femenino , Infecciones por VIH/epidemiología , Infecciones por VIH/psicología , Humanos , Masculino , Trastornos Mentales/epidemiología , Trastornos Mentales/psicología , Evaluación de Resultado en la Atención de Salud , Pobreza , Trastornos Relacionados con Sustancias/epidemiología , Trastornos Relacionados con Sustancias/psicología
14.
Pharmaceuticals (Basel) ; 13(1)2020 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-31936208

RESUMEN

A promising strategy to improve the effectivity of anticancer treatment and decrease its side effects is to modulate drug release by using nanoparticulates (NPs) as carriers. In this study, methotrexate-loaded chitosan-polyanion nanoparticles were produced by polyelectrolyte complexation assisted by high-intensity sonication, using several anionic polymers, such as the sodium and potassium salts of poly(maleic acid-alt-ethylene) and poly(maleic acid-alt-octadecene), here named PAM-2 and PAM-18, respectively. Such NPs were analyzed and characterized according to particle size, polydispersity index, zeta potential and encapsulation efficiency. Likewise, their physical stability was tested at 4 °C and 40 °C in order to evaluate any change in the previously mentioned particle parameters. The in vitro methotrexate release was assessed at a pH of 7.4, which simulated physiological conditions, and the data were fitted to the heuristic models of order one, Higuchi, Peppas-Sahlin and Korsmeyer-Peppas. The results revealed that most of the MTX-chitosan-polyanion NPs have positive zeta potential values, sizes <280 nm and monodisperse populations, except for the NPs formed with PAM-18 polyanions. Further, the NPs showed adequate physical stability, preventing NP-NP aggregation. Likewise, these carriers modified the MTX release by an anomalous mechanism, where the NPs formed with PAM-2 polymer led to a release mechanism controlled by diffusion and relaxation, whereas the NPs formed with PAM-18 led to a mainly diffusion-controlled release mechanism.

15.
J Public Health Manag Pract ; 26(2): 176-179, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31995548

RESUMEN

CONTEXT: While the New York City Department of Health and Mental Hygiene (DOHMH) can use agency-wide emergency activation to respond to a hepatitis A virus-infected food handler, there is a need to identify alternative responses that conserve scarce resources. OBJECTIVE: To compare the costs incurred by DOHMH of responding to a hepatitis A case in restaurant food handlers using an agency-wide emergency activation (2015) versus the cost of collaborating with a private network of urgent care clinics (2017). DESIGN: We partially evaluate the costs incurred by DOHMH of responding to a hepatitis A case in a restaurant food handler using agency-wide emergency activation (2015) with the cost of collaborating with a private network of urgent care clinics (2017) estimated for a scenario in which DOHMH incurred the retail cost of services rendered. RESULTS: Costs incurred by DOHMH for emergency activation were $65 831 ($238 per restaurant employee evaluated) of which DOHMH personnel services accounted for 85% ($55 854). Costs of collaboration would have totaled $50 914 ($253 per restaurant employee evaluated) of which personnel services accounted for 6% ($3146). CONCLUSIONS: Accounting for incident size, collaborating with the clinic network was more expensive than agency-wide emergency activation, though required fewer DOHMH personnel services.


Asunto(s)
Costos y Análisis de Costo/métodos , Hepatitis A/economía , Salud Pública/economía , Costos y Análisis de Costo/estadística & datos numéricos , Brotes de Enfermedades/estadística & datos numéricos , Manipulación de Alimentos , Hepatitis A/epidemiología , Virus de la Hepatitis A/patogenicidad , Humanos , Ciudad de Nueva York/epidemiología , Salud Pública/métodos , Salud Pública/estadística & datos numéricos , Restaurantes/organización & administración , Restaurantes/estadística & datos numéricos
16.
Polymers (Basel) ; 11(12)2019 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-31817917

RESUMEN

Cancer is one of the most serious public health problems that affect humanity. Diverse delivery systems of anticancer drugs have been developed to enhance the treatment effectiveness and patient compliance. Thus, drug delivery systems from polymeric films could be an interesting and promising alternative, especially for skin chemotherapeutics. In this work, polymeric films based on glutathione-chitosan conjugates with degrees of thiolation of 4.4%, 5.1% and 7.0% were synthetized by casting-evaporation method and subsequent loading with methotrexate. The surface properties of these films were evaluated by contact angle and spreading rate measurements. The sessile drop methods along with the thermodynamic parameter of work of adhesion were determined using the Young-Dupré semi-empirical model. The in vitro methotrexate release was assessed at a pH of 4.5 and 7.4 simulating physiological conditions. Data from the resulting profiles were fitted to the order one, Higuchi, Peppas-Sahlin and Korsmeyer-Peppas kinetic models. The results suggest a strong relationship between the thiolation degree and hydrophilic surface properties such as contact angle and water spreading rate, whereas the work of adhesion was not significantly affected. Further, these polymer films could control the methotrexate release through diverse mechanisms such as diffusion and relaxation depending on the thiolation degree and the aqueous medium employed. In fact, as thiolation degree increased, the release mechanism shifted from a primary diffusional type towards a predominant relaxation-driven mechanism. These polymer films could be used as modified systems for anticancer local delivery.

17.
Polymers (Basel) ; 11(11)2019 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-31731554

RESUMEN

Recently, one of the promising strategies to fight sensitive and resistant bacteria, and decrease the morbidity and mortality rates due to non-nosocomial infections, is to use antibiotic-loaded nanoparticles. In this study, ampicillin-loaded chitosan-polyanion nanoparticles were produced through the techniques of ionic gelation and polyelectrolyte complexation assisted by high-intensity sonication, using several crosslinking agents, including phytic acid (non-polymeric polyanion), sodium and potassium salts of poly(maleic acid-alt-ethylene) and poly(maleic acid-alt-octadecene) (polymeric polyanions). These nanoparticles were analysed and characterised in terms of particle size, polydispersity index, zeta potential and encapsulation efficiency. The stability of these nanosystems was carried out at temperatures of 4 and 40 °C, and the antimicrobial effect was determined by the broth microdilution method using sensitive and resistant Staphylococcus aureus strains. The results reveal that most of the nanosystems have sizes <220 nm, positive zeta potential values and a monodisperse population, except for the nanoparticles crosslinked with PAM-18 polyanions. The nanometric systems exhibited adequate stability preventing aggregation and revealed a two-fold increase in antimicrobial activity when compared with free ampicillin. This study demonstrates the potential application of synthesised nanoparticles in the field of medicine, especially for treating infections caused by pathogenic S. aureus strains.

18.
AIDS ; 33(6): 965-972, 2019 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-30946150

RESUMEN

BACKGROUND: Atripla dose reduction decreases subclinical toxicity and maintains viral suppression in HIV+ individuals but the virological efficacy and immunological safety of this strategy needs to be further confirmed. METHODS: Virologically suppressed HIV-infected adults on Atripla once-daily were randomized 1 : 1 to reduce therapy to 3 days a week (3W, n = 30) or to maintain it unchanged (once-daily, n = 31). HIV-1 reservoir (total and integrated HIV-1 DNA in CD4 cells) and immunological cell activation (CD38 and HLA-DR), senescence (CD57 and CD28), apoptosis (annexinV) as well as T-naive, effector memory (TEM) (CCR7, CD45RA) and stem cell memory (TSCM) (CD954 and CD27) populations were measured at baseline, 24 and 48 weeks. RESULTS: No differences on activation, senescence or apoptosis of both CD4 and CD8 T cells were observed on follow-up. Nave CD4 T-cell proportion showed a significant decrease in the 3W group (mean ±â€ŠSD): 24.6 ±â€Š13.7 vs. 20.5 ±â€Š12.9 (P = 0.002). No differences in both plasma viral load and HIV reservoir were detected on follow-up. CD4 TSCM levels at 48 weeks correlated with basal integrated HIV-1 DNA in the 3W group but not in the once-daily group. A post hoc analysis of data prior to the study entry revealed a higher viral load zenith and a trend to lower CD4 nadir in 3W vs. once-daily group. CONCLUSION: No significant immunological or viral changes were induced in the 3W group confirming the virological efficacy and immunogical safety of this strategy. In-depth virological and immunological analyses are useful in providing additional information in antiretroviral switching studies (Clinical Trials.gov: NCT01778413).


Asunto(s)
Antirretrovirales/administración & dosificación , Terapia Antirretroviral Altamente Activa/métodos , Combinación Efavirenz, Emtricitabina y Fumarato de Tenofovir Disoproxil/administración & dosificación , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/virología , Adulto , Antirretrovirales/efectos adversos , Combinación Efavirenz, Emtricitabina y Fumarato de Tenofovir Disoproxil/efectos adversos , Femenino , Infecciones por VIH/inmunología , Humanos , Activación de Linfocitos , Recuento de Linfocitos , Masculino , Persona de Mediana Edad , Carga Viral
19.
AIDS Behav ; 23(9): 2315-2325, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30879212

RESUMEN

We conducted a randomized controlled trial to determine whether, for homeless persons living with HIV/AIDS (PLWHA), rapid re-housing can improve housing and HIV viral suppression more than standard housing assistance. We recruited 236 PLWHA from HIV emergency housing in New York City (NYC) and randomized them to: (1) Enhanced Housing Placement Assistance (EHPA), i.e., immediate assignment to a case manager to rapidly re-house the client and provide 12 months of case management or (2) usual services, i.e., referral to an NYC housing placement program for which all HIV emergency housing residents were eligible. We compared time to stable housing placement and percentage virally suppressed from baseline to 12 months. EHPA clients were placed faster than usual services clients (p = 0.02; 25% placed by 150 days vs. 243 days, respectively), more likely to be placed [adjusted hazards ratio = 1.8; 95% confidence interval(CI) 1.1-2.8], and twice as likely to achieve or maintain suppression (adjusted odds ratio 2.1; 95% CI 1.1-4.0).


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Personas con Mala Vivienda/estadística & datos numéricos , Asistencia Pública/estadística & datos numéricos , Vivienda Popular , Adulto , Manejo de Caso , Femenino , Infecciones por VIH/diagnóstico , Infecciones por VIH/psicología , Humanos , Masculino , Ciudad de Nueva York , Evaluación de Resultado en la Atención de Salud , Resultado del Tratamiento
20.
Antioxidants (Basel) ; 8(2)2019 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-30736339

RESUMEN

This study deals with the extraction, optimization, and evaluation of the antioxidant and antimicrobial activities of bioactive compounds obtained from the seeds of annatto using microwave-assisted extraction as compared to leaching. Annatto seeds were subjected to a microwave treatment of 2450 MHz and power of 700 watts using a response surface design involving four factors: pH (4⁻11), solvent concentration (ethanol) (50⁻96 %), solvent-to-seed ratio (2⁻10), and microwave exposure time (0⁻5 min). The contents of polyphenol compounds and bixin were taken as response variables. Subsequently, the antioxidant and antimicrobial activities were assessed at the optimal processing conditions predicted by the experimental design. Microwaves, solvent concentration, and the solvent-to-seed ratio showed a statistically significant effect for the extraction of polyphenol compounds and bixin. Thus, microwaves accelerated the extraction of those compounds and the slight increase in temperature caused some degradation of the polyphenol compounds. The microwave-assisted extraction increased the contents of polyphenols and bixin along with their antioxidant activity as compared to leaching extraction. However, this technique does not significantly improve the antimicrobial activity against Bacillus cereus and Staphylococcus aureus.

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