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1.
Infection ; 50(5): 1321-1328, 2022 Oct.
Article in English | MEDLINE | ID: mdl-35562568

ABSTRACT

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.


Subject(s)
COVID-19 , SARS-CoV-2 , Antiviral Agents , Hospitals , Humans , Viral Load
2.
J Food Sci Technol ; 59(5): 1665-1676, 2022 May.
Article in English | MEDLINE | ID: mdl-35531395

ABSTRACT

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.

3.
Molecules ; 26(9)2021 Apr 22.
Article in English | MEDLINE | ID: mdl-33921948

ABSTRACT

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.


Subject(s)
Clove Oil/chemistry , Clove Oil/pharmacology , Lipids/chemistry , Oils, Volatile/chemistry , Oils, Volatile/pharmacology , Anti-Infective Agents/chemistry , Anti-Infective Agents/pharmacology , Antioxidants/chemistry , Antioxidants/pharmacology , Chemical Phenomena , Mechanical Phenomena , Molecular Structure , Spectroscopy, Fourier Transform Infrared , Structure-Activity Relationship , Waxes/chemistry , X-Ray Diffraction
4.
Am J Public Health ; 110(7): 1068-1075, 2020 07.
Article in English | MEDLINE | ID: mdl-32437285

ABSTRACT

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.


Subject(s)
HIV Infections , Housing , Patient Participation/statistics & numerical data , Program Evaluation , Adult , Aged , CD4 Lymphocyte Count/statistics & numerical data , Female , Humans , Male , Middle Aged , New York City/epidemiology , Outcome Assessment, Health Care , Poverty/statistics & numerical data , Viral Load
5.
AIDS Behav ; 24(11): 3252-3263, 2020 Nov.
Article in English | MEDLINE | ID: mdl-32180090

ABSTRACT

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.


Subject(s)
Anti-HIV Agents/therapeutic use , HIV Infections/drug therapy , Ill-Housed Persons/psychology , Mental Disorders/complications , Public Assistance/statistics & numerical data , Public Housing/statistics & numerical data , Substance-Related Disorders/complications , Adult , Female , HIV Infections/epidemiology , HIV Infections/psychology , Humans , Male , Mental Disorders/epidemiology , Mental Disorders/psychology , Outcome Assessment, Health Care , Poverty , Substance-Related Disorders/epidemiology , Substance-Related Disorders/psychology
6.
J Public Health Manag Pract ; 26(2): 176-179, 2020.
Article in English | MEDLINE | ID: mdl-31995548

ABSTRACT

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.


Subject(s)
Costs and Cost Analysis/methods , Hepatitis A/economics , Public Health/economics , Costs and Cost Analysis/statistics & numerical data , Disease Outbreaks/statistics & numerical data , Food Handling , Hepatitis A/epidemiology , Hepatitis A virus/pathogenicity , Humans , New York City/epidemiology , Public Health/methods , Public Health/statistics & numerical data , Restaurants/organization & administration , Restaurants/statistics & numerical data
7.
AIDS Behav ; 23(9): 2315-2325, 2019 Sep.
Article in English | MEDLINE | ID: mdl-30879212

ABSTRACT

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).


Subject(s)
Anti-HIV Agents/therapeutic use , HIV Infections/drug therapy , Ill-Housed Persons/statistics & numerical data , Public Assistance/statistics & numerical data , Public Housing , Adult , Case Management , Female , HIV Infections/diagnosis , HIV Infections/psychology , Humans , Male , New York City , Outcome Assessment, Health Care , Treatment Outcome
8.
AIDS Behav ; 23(3): 784-791, 2019 Mar.
Article in English | MEDLINE | ID: mdl-30680539

ABSTRACT

Persons with HIV who are receiving housing services often have high rates of engagement in care, yet many are not virally suppressed. We linked data from the New York City Housing Opportunities for Persons with AIDS (HOPWA) program to electronically reported laboratory tests from the HIV surveillance registry to examine factors associated with a lack of viral suppression. Of 1491 HOPWA consumers, 523 (35.1%) were not durably suppressed, and 253 (17.0%) were unsuppressed at their last viral load test. Substance use, age < 27 years, and emergency housing all independently predicted lack of durable viral suppression and lack of viral suppression at last viral load test.


Subject(s)
Anti-Retroviral Agents/therapeutic use , HIV Infections/drug therapy , HIV Infections/virology , HIV/drug effects , Public Health Surveillance/methods , Substance-Related Disorders/complications , Viral Load/drug effects , Acquired Immunodeficiency Syndrome , Adult , Female , HIV Infections/epidemiology , Housing , Humans , Male , Middle Aged , New York City , Registries , Substance-Related Disorders/psychology , Sustained Virologic Response , Young Adult
9.
AIDS Behav ; 19(11): 2087-96, 2015 Nov.
Article in English | MEDLINE | ID: mdl-25631320

ABSTRACT

The federal Housing Opportunities for Persons with AIDS (HOPWA) program addresses housing needs of low-income persons living with HIV/AIDS (PLWHA). The New York City (NYC) Department of Health and Mental Hygiene oversees 22 HOPWA contracts for over 2,400 clients, and manages the NYC HIV Registry. HOPWA clients (N = 1,357) were matched to a random 20 % sample of other PLWHA (N = 13,489). Groups were compared on HIV care retention, viral suppression, and rebound. HOPWA clients were, on average, 3 years younger and more likely to be concurrently diagnosed with HIV and AIDS. While HOPWA clients were more likely to be retained in care (94 vs. 82 %; mOR = 2.97, 95 % CI 2.35-3.74), they were no more likely to achieve suppression (84 vs. 86 %; mOR = 0.85, 95 % 0.70-1.03) and were more likely to rebound (11 vs. 7 %; mOR = 1.45; 95 % CI 1.10-1.91). HIV care retention does not fully translate to virologic suppression in this low-income service population.


Subject(s)
Continuity of Patient Care/statistics & numerical data , HIV Infections/drug therapy , Housing , Patient Acceptance of Health Care/statistics & numerical data , Public Health Surveillance/methods , Adult , CD4 Lymphocyte Count , HIV Infections/epidemiology , HIV Infections/prevention & control , Humans , Male , Middle Aged , New York City/epidemiology , Population Surveillance , Program Evaluation , Propensity Score , Registries , Socioeconomic Factors , Viral Load
10.
Chem Pharm Bull (Tokyo) ; 62(3): 281-7, 2014.
Article in English | MEDLINE | ID: mdl-24583783

ABSTRACT

Several compaction models have been attempted to explain the compression and compaction phenomena of excipients. However, the resulting parameters could be influenced by the compaction platform such as dwell time, compact mass, geometry and type of material. The goal of this study is to assess the effect of these variables on the densification parameters obtained from key models such as Heckel, non-linear Heckel, Kawakita, Carstensen, and Leuenberger. The relationship among the parameters derived was determined by employing a Principal Component Analysis. Results indicated that factors such as compact geometry, consolidation time and compact mass had a negligible impact on parameters such as tensile strength, yield pressure and compressibility. On the contrary, the excipient type had the largest influence on these parameters. Further, the Leuenberger (γ) and Carstensen (f) parameters were highly correlated and related to the excipient deformation mechanism. Sorbitol and PVP-k30 were the most highly compactable excipients and were characterized for having a low yield pressure (P(y)), compressibility (a), and critical porosity (ε(c)). The magnitude of these parameters was highly dependent on the consolidation behavior of each material.


Subject(s)
Drug Compounding/methods , Excipients , Tablets , Compressive Strength , Models, Statistical , Porosity , Principal Component Analysis , Tensile Strength
11.
PLoS One ; 18(5): e0285765, 2023.
Article in English | MEDLINE | ID: mdl-37172065

ABSTRACT

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.


Subject(s)
HIV Infections , Ill-Housed Persons , Humans , Housing , Public Housing , New York City/epidemiology , HIV Infections/epidemiology , HIV Infections/therapy , Social Problems , Viral Load
12.
Chem Pharm Bull (Tokyo) ; 60(5): 603-11, 2012.
Article in English | MEDLINE | ID: mdl-22689398

ABSTRACT

The effect of silicification on the tableting performance of microcrystalline cellulose II (MCCII) was assessed through coprocessing with fumed silica via spray drying and wet granulation at the 98:2, 95:5, 90:10 and 80:20 ratios. Compacts produced by spray drying and wet granulation rendered better tensile strength than MCCII. The Kawakita and Heckel models implied that silicification increased compressibility and decreased the plastic deforming behavior and densification by die filling at the early stage of compression for MCCII. It also decreased the sensitivity to hydrophobic lubricants such as magnesium stearate, especially for the spray-dried products due to the competing effect with magnesium stearate. Further, silicification decreased the high elastic recovery typical of MCCII due to the increase in specific surface area and fragmenting behavior which contributed to the formation of stronger compacts. Moreover, silicification did not affect the fast disintegrating properties and release rates of poorly soluble drugs such as griseofulvin formulated in tablets compared to those of Prosolv® SMCC 50 and Prosolv® SMCC 90. The new silicified materials are appropriate to formulate fast disintegrating tablets by direct compression.


Subject(s)
Cellulose/chemistry , Drug Compounding , Excipients/chemistry , Tablets/chemistry , Stearic Acids/chemistry , Tensile Strength
13.
Drug Dev Ind Pharm ; 38(2): 209-26, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22088231

ABSTRACT

AIM: In recent years, coprocessing has been the most successful approach to improve and correct the functionality of excipients. The aim of this study is to coprocessed cellulose II with SiO(2) and to evaluate the resulting powder and tableting properties. METHODS: Novel cellulose II:SiO(2) (98:2, 95:5, 90:10 and 80:20 w/w ratios) composites were produced by spray drying, wet granulation and spheronization techniques and the resulting powder and tableting properties were assessed. RESULTS: Cellulose II:SiO(2) composites produced by spray- drying exhibited spherical/oblongate shape, narrow distribution and mean diameter from 51 to 75 µm. The composites produced by wet granulation had larger distribution, granular shape and a mean diameter from 105 to 129 µm. The spheronized composites showed the highest size (from 148 to 450 µm) and round shape. Bulk and tap densities and flow were reduced as the silicification level increased in the spray dried and wet granulated materials. Likewise, silicification increased the true density, porosity and surface roughness of these materials. Water sorption decreased only at silicification level of 20% being comparable to the ones shown by Prosolv(®) samples. Contact angles of all cellulose II materials were lower than those of cellulose I except for Celphere203 indicating better wettability. A 5% and 10% silicification levels rendered the strongest compacts for the spray dried and wet granulated materials, respectively. Silicification did not affect the fast disintegration properties of MCCII. CONCLUSIONS: Coprocessing proved to be useful tool to modify the powder and tableting properties of cellulose II.


Subject(s)
Cellulose/chemistry , Drug Compounding/methods , Excipients/chemistry , Silicon Dioxide/chemistry , Particle Size , Powders/chemistry , Tablets/chemistry
14.
Drug Dev Ind Pharm ; 38(10): 1159-70, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22966909

ABSTRACT

It is necessary to have excipients with excellent functional properties to compensate for the poor mechanical properties and low aqueous solubility of the emerging active ingredients. Therefore, around 80% of the current drugs are not suitable for direct compression and more advanced excipients are required. Further, conventional grades of excipients cannot accommodate the technologically advanced high speed rotary tablet presses which require a powder with excellent flow, good compressibility, compactibility, particle size distribution and homogeneity of the ingredients. Co-processed excipients have been created to enhance the functional properties of the excipients and reduce their drawbacks. Co-processing is defined as the combination of two or more excipients by a physical process. Co-processed excipients are adequate for direct compression since they become multifunctional and thus, their dilution potential is high eliminating the need for many excipients in a formulation. In some cases, they are able to hold up to 50% of the drug in a formulation rendering compacts of good tableting properties. This study describes and discusses the functionality enhancement of commercial and investigational excipients through co-processing.


Subject(s)
Chemistry, Pharmaceutical/methods , Excipients/chemistry , Tablets/chemistry , Technology, Pharmaceutical/methods , Compressive Strength , Particle Size , Powders/chemistry , Solubility
15.
AAPS PharmSciTech ; 13(4): 1054-62, 2012 Dec.
Article in English | MEDLINE | ID: mdl-22899380

ABSTRACT

Spironolactone is a drug derived from sterols that exhibits an incomplete oral absorption due to its low water solubility and slow dissolution rate. In this study, formulations of spironolactone with four disintegrants named as croscarmellose sodium, crospovidone, sodium starch glycolate and microcrystalline cellulose II (MCCII) were conducted. The effect of those disintegrants on the tensile strength, disintegration time and dissolution rate of spironolactone-based compacts was evaluated using a factorial design with three categorical factors (filler, lubricant, and disintegrant). The swelling values, water uptake and water sorption studies of these disintegrants all suggested that MCCII compacts disintegrate by a wicking mechanism similar to that of crospovidone, whereas a swelling mechanism was dominant for sodium starch glycolate and croscarmellose sodium. The disintegration time of MCCII and sodium starch glycolate remained unchanged with magnesium stearate. However, this lubricant delayed the disintegration time of crospovidone and croscarmellose sodium. MCCII presented the fastest disintegration time independent of the medium and lubricant employed. The water sorption ratio and swelling values determined sodium starch glycolate followed by croscarmellose sodium as the largest swelling materials, whereas crospovidone and MCCII where the least swelling disintegrants. The swelling property of sodium starch glycolate and croscarmellose sodium was strongly affected by the medium pH. The disintegration time of spironolactone compacts was faster when starch was used as a filler due to the formation of soft compacts. In this case, the type of filler employed rather than the disintegrant had a major effect on the disintegration and dissolution times of spironolactone.


Subject(s)
Carboxymethylcellulose Sodium/chemistry , Cellulose/chemistry , Povidone/chemistry , Spironolactone/chemistry , Starch/analogs & derivatives , Absorption , Chemistry, Pharmaceutical/methods , Excipients/chemistry , Solubility , Starch/chemistry , Tensile Strength , Water/chemistry
16.
Foods ; 11(19)2022 Oct 06.
Article in English | MEDLINE | ID: mdl-36230192

ABSTRACT

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.

17.
Polymers (Basel) ; 14(9)2022 Apr 26.
Article in English | MEDLINE | ID: mdl-35566922

ABSTRACT

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.

18.
Chem Pharm Bull (Tokyo) ; 59(5): 603-7, 2011.
Article in English | MEDLINE | ID: mdl-21532198

ABSTRACT

Microcrystalline cellulose I (MCCI) is an excipient used as a diluent, disintegrant, glidant and binder for the production of pharmaceutical tablets. In this work, microcrystalline cellulose II (MCCII) was obtained from cotton fibers by basic treatment with 7.5 N NaOH followed by an acid hydrolysis. MCCI and MCCII materials were processed by wet granulation, dry granulation and spray drying. Either the polymorphic form or processing had no effects on the particle morphology or particle size. However, MCCII powders had a higher porosity, less packing tendency, degree of crystallinity, degree of polymerization and density, but a faster disintegration than MCCI. The tensile strength of MCCI was highly affected by the wet and dry granulation processes. Most of the resulting powder and tableting properties were dependent on the polymorphic form of cellulose, rather than on the processing employed.


Subject(s)
Cellulose/pharmacology , Excipients/pharmacology , Tablets/pharmacology , Technology, Pharmaceutical/methods , Cellulose/chemistry , Crystallization , Drug Stability , Excipients/chemistry , Hydrolysis , Particle Size , Photomicrography , Powders/chemistry , Powders/pharmacology , Sodium Hydroxide/chemistry , Tablets/chemistry , Tensile Strength , X-Ray Diffraction
19.
Data Brief ; 31: 106014, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32715043

ABSTRACT

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.

20.
Pharmaceuticals (Basel) ; 13(1)2020 Jan 08.
Article in English | MEDLINE | ID: mdl-31936208

ABSTRACT

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.

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