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1.
Appl Spectrosc ; : 37028241249768, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38747750

RESUMEN

Tuning the 8-anilino-1-naphthalenesulfonic acid (ANS) structure usually requires harsh conditions and long reaction times, which can result in low yields. Herein, ANS was modified to form an ANS group of uniform materials based on organic salts (GUMBOS), prepared with simple metathesis reactions and distinct cations, namely tetrabutylammonium (N4444), tetrahexylammonium (N6666), and tetrabutylphosphonium (P4444). These ANS-based GUMBOS were investigated as fluorescent probes for membrane binding studies with four proteins having distinct physicochemical properties. Liposomes of 1,2-dimyristoyl-sn-glycero-3-phosphocholine were employed as membrane models as a result of their ability to mimic the structure and chemical composition of cell membranes. Changes in fluorescence intensity were used to monitor protein binding to liposomes, and adsorption data were fitted to a Freundlich-like isotherm. It was determined that [N4444][ANS] and [P4444][ANS] GUMBOS have enhanced optical properties and lipophilicity as compared to parent ANS. As a result, these two GUMBOS were selected for subsequent protein-membrane binding studies. Both [N4444][ANS] and [P4444][ANS] GUMBOS and parent ANS independently reached membrane saturation within the same concentration range. Furthermore, distinct fluorescence responses were observed upon the addition of proteins to each probe, which demonstrates the impact of properties such as lipophilicity on the binding process. The relative maintenance of binding cooperativity and maximum fluorescence intensity suggests that proteins compete with ANS-based probes for the same membrane binding sites. Finally, this GUMBOS-based approach is simple, rapid, and involves relatively small amounts of reagents, making it attractive for high-throughput purposes. These results presented herein can also provide relevant information for designing GUMBOS with ameliorated properties.

2.
J Funct Biomater ; 15(3)2024 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-38535260

RESUMEN

The study and characterization of the biophysical properties of membranes and drug-membrane interactions represent a critical step in drug development, as biological membranes act as a barrier that the drug must overcome to reach its active site. Liposomes are widely used in drug delivery to circumvent the poor aqueous solubility of most drugs, improving systemic bioavailability and pharmacokinetics. Further, they can be targeted to deliver to specific disease sites, thus decreasing drug load, and reducing side effects and poor adherence to treatment. To improve drug solubility during liposome preparation, DMSO is the most widely used solvent. This raises concern about the potential effect of DMSO on membranes and leads us to investigate, using DSC and EPR, the influence of DMSO on the behavior of lipid model membranes of DMPC and DPPC. In addition, we tested the influence of DMSO on drug-membrane interaction, using compounds with different hydrophobicity and varying DMSO content, using the same experimental techniques. Overall, it was found that with up to 10% DMSO, changes in the bilayer fluidity or the thermotropic properties of the studied liposomes were not significant, within the experimental uncertainty. For higher concentrations of DMSO, there is a stabilization of both the gel and the rippled gel phases, and increased bilayer fluidity of DMPC and DPPC liposomes leading to an increase in membrane permeability.

3.
Sensors (Basel) ; 24(3)2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38339741

RESUMEN

Iodine is an essential micronutrient for humans due to its fundamental role in the biosynthesis of thyroid hormones. As a key parameter to assess health conditions, iodine intake needs to be monitored to ascertain and prevent iodine deficiency. Iodine is available from various food sources (such as seaweed, fish, and seafood, among others) and dietary supplements (multivitamins or mineral supplements). In this work, a microfluidic paper-based analytical device (µPAD) to quantify iodide in seaweed and dietary supplements is described. The developed µPAD is a small microfluidic device that emerges as quite relevant in terms of its analytical capacity. The quantification of iodide is based on the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) by hydrogen peroxide in the presence of iodine, which acts as the catalyst to produce the blue form of TMB. Additionally, powder silica was used to intensify and uniformize the colour of the obtained product. Following optimization, the developed µPAD enabled iodide quantification within the range of 10-100 µM, with a detection limit of 3 µM, and was successfully applied to seaweeds and dietary supplements. The device represents a valuable tool for point-of-care analysis, can be used by untrained personnel at home, and is easily disposable, low-cost, and user-friendly.


Asunto(s)
Yodo , Técnicas Analíticas Microfluídicas , Humanos , Microfluídica , Yoduros , Suplementos Dietéticos/análisis , Yodo/análisis , Dispositivos Laboratorio en un Chip , Papel
4.
Talanta ; 271: 125683, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38301372

RESUMEN

This work describes the development of a microfluidic paper-based analytical device (µPAD) for the determination of copper in fresh and marine waters. A functionalized rhodamine-based chelator was synthesized and used as a chromogenic reagent, forming a highly intense pink complex with the analyte. The aim was to create a paper device that offers optimal performance and provides in-situ, rapid and cost-effective analysis in line with World Health Organization guidelines. The influence on the determination of several physical and chemical parameters was evaluated aiming to achieve the best performance. Under optimised conditions, a linear correlation was established in the range of 0.05-0.50 mg L-1 of copper, with a limit of detection of 10 µg L-1. The accuracy of the proposed method was assessed by comparing the results obtained with the developed µPAD and the results obtained with Inductively Coupled Plasma measurements (RE < 10 %). Recovery studies were also performed using different types of water samples with no need for any prior sample pre-treatment: tap, well, river and seawater. The average recovery percentage of 101 % (RSD = 4.3 %) was obtained, a clear indication of no multiplicative matrix interferences.

5.
Heliyon ; 10(1): e23198, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38163248

RESUMEN

Nanoparticle (NP) research is an area of scientific interest with high potential for application in biomedical, optical, and electronic fields. Due to their relatively large surface area compared to their mass, NPs can be more chemically reactive and change their reactive strength or other properties. NP-based drug delivery systems provide transport and an effective and controlled way to release the drugs. This work aimed to study the solubility and biological activity of nano-encapsulated copper metal complexes for the induction of toxicity and mortality in larvae of Aedes aegypti mosquitoes. After the nano-encapsulated metal complexes were prepared, the efficiency of this incorporation was determined by electron paramagnetic resonance, and toxicity bioassays were performed. The polymeric-based PLGA NPs encapsulating metal complexes exhibited high toxicity and specificity for target organisms (insect vectors, i.e., A. aegypti), with relatively less environmental impact and long-term control of their breeding.

6.
Int J Mol Sci ; 24(21)2023 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-37958659

RESUMEN

Over the last four decades, vanadium compounds have been extensively studied as potential antidiabetic drugs. With the present review, we aim at presenting a general overview of the most promising compounds and the main results obtained with in vivo studies, reported from 1899-2023. The chemistry of vanadium is explored, discussing the importance of the structure and biochemistry of vanadate and the impact of its similarity with phosphate on the antidiabetic effect. The spectroscopic characterization of vanadium compounds is discussed, particularly magnetic resonance methodologies, emphasizing its relevance for understanding species activity, speciation, and interaction with biological membranes. Finally, the most relevant studies regarding the use of vanadium compounds to treat diabetes are summarized, considering both animal models and human clinical trials. An overview of the main hypotheses explaining the biological activity of these compounds is presented, particularly the most accepted pathway involving vanadium interaction with phosphatase and kinase enzymes involved in the insulin signaling cascade. From our point of view, the major discoveries regarding the pharmacological action of this family of compounds are not yet fully understood. Thus, we still believe that vanadium presents the potential to help in metabolic control and the clinical management of diabetes, either as an insulin-like drug or as an insulin adjuvant. We look forward to the next forty years of research in this field, aiming to discover a vanadium compound with the desired therapeutic properties.


Asunto(s)
Diabetes Mellitus , Compuestos de Vanadio , Animales , Humanos , Hipoglucemiantes/farmacología , Hipoglucemiantes/uso terapéutico , Hipoglucemiantes/química , Compuestos de Vanadio/farmacología , Compuestos de Vanadio/uso terapéutico , Compuestos de Vanadio/química , Vanadio/química , Diabetes Mellitus/tratamiento farmacológico , Insulina/uso terapéutico , Insulina Regular Humana/uso terapéutico
7.
Artículo en Inglés | MEDLINE | ID: mdl-38010482

RESUMEN

Black, Hispanic, and Asian individuals, the three largest US racial/ethnic minorities, continue to suffer disproportionately from breast, cervical, and colon cancers largely because cancer screening continues to be underutilized even after decades of availability. This study examined the utility of theoretically grounded and culturally adapted in-person theater monologues aimed at promoting early detection screening among the three highest population racial/ethnic groups in Harris County, Houston, TX. Nine monologues were created to promote cancer screening and early detection for breast, cervical, and colorectal cancers in three different languages (English, Spanish, Vietnamese) and targeting underserved Black, Hispanic, and Vietnamese adult Harris County residents. From January 2014 to March 2020, 265 live monologue outreach events were held with 110 focused on prevention and screening for breast cancer, 75 for colorectal cancer, and 80 for cervical cancer. A total of 5989 individuals attended these outreach events and 86.3% completed the post-performance evaluation survey. Overall for all monologues, 6.6% of participants reported a positive change in their intent to screen from 75.7 to 82.3% after intervention (p < 0.001) and audience member scores on knowledge questions for all three cancers were mostly positive. Importantly, early detection questions for all three cancers were over 90% correct for all respondents, and well over 70% for the various groups. The findings revealed opportunities for improving monologue content to cultivate cancer early detection and screening knowledge. Results suggest that a theater-based approach may be an effective strategy to disseminate cancer screening education, improve knowledge, and increase intent to obtain screening among medically underserved communities.

8.
Hisp Health Care Int ; : 15404153231210454, 2023 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-37899727

RESUMEN

Latino day laborers in the United States provide skilled labor to businesses and homeowners through informal work arrangements. We conducted exploratory qualitative research with Latino day laborers in Houston, Texas, to investigate their perceptions of safety risks and circumstances related to work-related injuries. We conducted focus groups with 34 participants and used risk mapping and body mapping activities to elicit greater engagement by the Latino day laborers in the conversations. Participants described physical, occupational, and psychosocial hazards that affected their risk for workplace injuries. They indicated a significant risk for injury was employers failing to provide proper tools or equipment for the job being done. The themes that emerged from the analysis were lack of control over employment conditions and the risk of performing unsafe work in order to meet financial needs. This formative qualitative research informed a pilot test and subsequent clinical trial of injury risk reduction strategies for Latino day laborers. Interventions to protect day laborers from work-related injuries should be informed by recognizing the employment and social dilemmas they confront.

9.
Int J Behav Med ; 2023 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-37853272

RESUMEN

BACKGROUND: The COVID-19 pandemic has created unprecedented stressors for caregivers due to social distancing requirements that simultaneously increased their responsibilities and reduced opportunities for social connection and support. This concurrent embedded mixed-methods study examined differences between caregivers and non-caregivers regarding the effects of social connectedness on perceived stress and explored challenges caregivers experienced related to social connectedness and perceived stress. METHOD: A national online survey containing forced-choice and free-response questions was administered between April and June 2020. The survey was distributed via social media advertisements and a crowdsourcing platform to eligible adult residents in the United States (US) fluent in either English or Spanish. Multivariable regression and thematic analysis were used to analyze the quantitative and qualitative data. Mixed-methods integration occurred during the data analysis, interpretation, and reporting phases. RESULTS: The study sample comprised 1540 US adults (1275 non-caregivers, 265 caregivers; 65% women; 36% racial/ethnic minorities). Relative to non-caregivers, caregivers had lower levels of social connectedness and higher levels of perceived stress. Social connectedness was also inversely related to perceived stress for non-caregivers (p < 0.001) and slightly but not significantly positively related to perceived stress for caregivers. Qualitative findings showed caregivers experienced a variety of stressors including fear of COVID-19 exposure to their care recipients, disruption to usual care routines, and difficulty accessing healthcare services that may have contributed to decrements in social connectedness and higher levels of perceived stress. CONCLUSION: Findings suggest social connectedness may be beneficial for reducing perceived stress, but its impact can vary depending on individual circumstances. Overall, findings support the idea that caregivers are a particularly vulnerable sub-group of the population and may benefit from more targeted support and interventions.

10.
Psychooncology ; 32(10): 1578-1585, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37698499

RESUMEN

OBJECTIVE: Oncology guidelines for distress management recommend use of the single-item distress thermometer (DT) and accompanying Problem List (PL) to identify patients with high distress levels and their potential sources of distress. However, oncology practices have yet to establish standardized protocols to screen and triage caregivers with high distress levels. With an eye toward integrating caregiver-centered support services into cancer care, this mixed-methods study sought to assess caregiver distress and challenges that may contribute to their distress. METHODS: Nineteen caregivers of metastatic breast cancer patients (60% female, 47% ethnic/racial minority) completed an interview and a survey comprised of the DT, the original 39-item PL, and five additional caregiver-specific PL items. RESULTS: Caregivers reported moderate distress levels and more than half exceeded the National Comprehensive Cancer Network (NCCN) cut-off, denoting significant distress. There was no association between caregiver distress and the number of items endorsed on the original PL. Qualitative analysis identified nine problem domains as areas of caregiver unmet need needs (i.e., practical challenges, caregiving responsibilities, social/relationship issues, caregiver and patient emotional well-being, caregiver and patient physical well-being, spiritual well-being, and communication). Two of the problem domains (caregiving responsibilities and communication) were not captured in any way by the original PL. CONCLUSION: With further research and development, the identified domains could serve as the basis for a caregiver-specific PL to facilitate triage and referral when incorporated as part of routine distress screening.

11.
J Hazard Mater ; 460: 132348, 2023 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-37625295

RESUMEN

The potential of pentapotassium bis(peroxymonosulphate) bis(sulphate) (OXONE) to control biofilms in drinking water distribution systems (DWDS) was evaluated and compared to chlorine disinfection. Mature biofilms of drinking water (DW)-isolated Stenotrophomonas maltophilia were formed using a simulated DWDS with a rotating cylinder reactor (RCR). After 30 min of exposure, OXONE at 10 × minimum bactericidal concentration (MBC) caused a significant 4 log reduction of biofilm culturability in comparison to the unexposed biofilms and a decrease in the number of non-damaged cells below the detection limit (4.8 log cells/cm2). The effects of free chlorine were restricted to approximately 1 log reduction in both biofilm culturability and non-damaged cells. OXONE in synthetic tap water (STW) at 25 ºC was more stable over 40 days than free chlorine in the same conditions. OXONE solution exhibited a disinfectant decrease of about 10% of the initial concentration during the first 9 days, and after this time the values remained stable. Whereas possible reaction of chlorine with inorganic and organic substances in STW contributed to free chlorine depletion of approximately 48% of the initial concentration. Electron paramagnetic resonance (EPR) spectroscopy studies confirmed the presence of singlet oxygen and other free radicals during S. maltophilia disinfection with OXONE. Overall, OXONE constitutes a relevant alternative to conventional DW disinfection for effective biofilm control in DWDS.


Asunto(s)
Agua Potable , Stenotrophomonas maltophilia , Cloro , Halógenos , Biopelículas , Cloruros , Potasio
12.
Methods Mol Biol ; 2709: 263-276, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37572287

RESUMEN

RNA nanoparticles are promising therapeutic platforms to improve radiotherapy since they can be functionalized with multiple small interfering RNAs (RNAi) to simultaneously silence critical radioresistance genes. Here we describe the transfer of RNA rings to mammalian cancer cells through reverse transfection, followed by in vitro irradiation and biological assays as surrogates' endpoints for radiotherapy efficacy.

13.
Molecules ; 28(9)2023 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-37175243

RESUMEN

In this work we pursued research involving the microwave-assisted N-alkylation of a NH pyrrolidine-fused chlorin with methyl 4-(bromomethyl) benzoate and subsequent ester hydrolysis as a straightforward strategy to obtain carboxylic acid functionality in the pyrrolidine-fused chlorin, as a single reaction product. We studied the reaction's scope by extending the N-alkylation of the free-base chlorin and its corresponding Zn(II) complex to other alkyl halides, including 1,4-diiodobutane, N-(2-bromoethyl)phthalimide, and 2-bromoethanaminium bromide. In addition, two new chlorin-dansyl dyads were synthesized by reacting dansyl chloride with the 2-aminoethyl pyrrolidine-fused chlorin (dyad 6) and NH pyrrolidine-fused chlorin (dyad 7). According to spectral studies, the linker length between the two fluorophores influences the response of the dyads to the solvent polarity. Because of the simplicity of these approaches, we believe it will enable access to a vast library of custom-tailored N-functionalized chlorins while preserving their important absorption and emission spectra as photosensitizers in photodynamic therapy (PDT) of cancer and photodynamic inactivation (PDI) of microorganisms.

14.
Foods ; 12(10)2023 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-37238888

RESUMEN

The packaging nets used for bell peppers act as a form of protection. However, the manufacturing is based on polymers that cause serious environmental problems. The effects of nets made of biodegradable materials, such as poly(lactic) acid (PLA), poly(butylene adipate-co-terephthalate) (PBAT), and cactus stem residues, were evaluated on four different colors of 'California Wonder' bell peppers stored over a 25-day storage period under controlled and ambient temperature conditions. Compared to commercial polyethylene nets, the bell peppers kept in the biodegradable nets did not show notable differences with respect to color, weight loss, total soluble solids, and titratable acidity. However, there were significant differences (p < 0.05) in terms of phenol content, carotenoids (orange bell peppers), anthocyanins, and vitamin C, with an overall tendency to show a higher content in those kept in PLA 60%/PBTA 40%/cactus stem flour 3% compared to commercial packaging. In addition, the same net notably reduced the development of bacteria, fungi, and yeasts during the storage of red, orange, and yellow bell peppers. As postharvest packaging for bell peppers, this net could be considered a viable option for the storage of this product.

15.
Biophys Chem ; 298: 107021, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37182237

RESUMEN

We performed an NMR and EPR study of the interaction of four [Ga(3,4-HPO)3] chelates with liposomes derived from a soybean extract (SEL) and simpler formulations using POPC (100%) and POPE:POPC (50%). Parent [Fe(3,4-HPO)3] chelates are eligible to prevent Iron Deficiency Chlorosis and we took advantage of the likenesses of the ions Fe (III) and Ga (III), and the fact their metal ion complexes are isostructural, to perform a combined NMR and EPR study to get information about the permeation properties of the complexes. The results demonstrate the presence of liposomes loaded with Ga-chelates and that the distribution of complexes alongside the bilayer is dependent on their structure. Two compounds, [Ga(mpp)3] and [Ga(etpp)3], have a higher affinity for the polar region of the liposome bilayer thus suggesting that their structure facilitates their permanence at the root-rhizosphere interface. Chelates [Ga(dmpp)3] and [Ga(mrb13)3] interact with all types of protons of the lipid bilayer thus implying that they travel all along the bilayer structure indicating their higher permeation properties through soybean membranes. The results obtained for compound, [Ga(mrb13)3], which has been included in this work but was not yet tested in plant supplementation experiments, encourage its testing in in vivo plant studies once this study revealed that it interacts strongly with the model membranes. If the results of the future experiments in plants are positive and consistent with the present membrane-interaction studies the latter could constitute a good screening test for future compounds thus saving reagents and time.


Asunto(s)
Complejos de Coordinación , Liposomas , Espectroscopía de Resonancia Magnética , Cetonas , Membrana Dobles de Lípidos
16.
J Geriatr Cardiol ; 20(1): 11-22, 2023 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-36875169

RESUMEN

OBJECTIVES: Syncope at age 65+ is associated with increased mortality, irrespective of cause. Syncope rules were designed to aid in risk-stratification but were only validated in the general adult population. Our objective was to determine if they can be applied to a geriatric population in predicting short-term adverse outcomes. METHODS: In this single-center retrospective study, we evaluated 350 patients aged 65+ presenting with syncope. Exclusion criteria included confirmed non-syncope, active medical condition, drug or alcohol-related syncope. Patients were stratified into high or low risk based on Canadian Syncope Risk Score (CSRS), Evaluation of Guidelines in Syncope Study (EGSYS), San Francisco Syncope Rule (SFSR), and Risk Stratification of Syncope in the Emergency Department (ROSE). Composite adverse outcomes at 48-hour and 30-day included all-cause mortality, major adverse cardiac and cerebrovascular events (MACCE), return emergency department visit, hospitalization, or medical intervention. We assessed each score's ability to predict the outcomes using logistic-regression and compared performances using receiver-operator curves. Multivariate analyses were performed to study the associations between recorded parameters and outcomes. RESULTS: CSRS outperformed with AUC of 0.732 (95% CI: 0.653-0.812) and 0.749 (95% CI: 0.688-0.809) for 48-h and 30-day outcomes, respectively. Sensitivities for CSRS, EGSYS, SFSR, and ROSE for 48-hour outcomes were 48%, 65%, 42% and 19%; and for 30-day outcomes were 72%, 65%, 30% and 55%, respectively. Atrial fibrillation/flutter on EKG, congestive heart failure, antiarrhythmics, systolic blood-pressure < 90 at triage, and associated chest pain highly correlated with 48-h outcomes. An EKG abnormality, heart disease history, severe pulmonary hypertension, BNP > 300, vasovagal predisposition, and antidepressants highly correlated with 30-day outcomes. CONCLUSIONS: Performance and accuracy of four prominent syncope rules were suboptimal in identifying high-risk geriatric patients with short-term adverse outcomes. We identified some significant clinical and laboratory information that may play a role in predicting short-term adverse events in a geriatric cohort.

17.
Front Oncol ; 13: 1089115, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36776295

RESUMEN

Cancer is a major public health concern worldwide responsible for high morbidity and mortality rates. Alternative therapies have been extensively investigated, and plant-derived compounds have caught the attention of the scientific community due to their chemopreventive and anticancer effects. Sulforaphane (SFN) is one of these naturally occurring agents, and studies have shown that it is able to target a specific cancer cell population displaying stem-like properties, known as cancer stem cells (CSCs). These cells can self-renewal and differentiate to form highly heterogeneous tumor masses. Notably, most of the conventional chemotherapeutic agents cannot target CSCs once they usually exist in a quiescent state and overall, the available cytotoxic drugs focus on highly dividing cells. This is, at least in part, one of the reasons why some oncologic patients relapse after standard therapy. In this review we bring together studies supporting not only the chemopreventive and anticancer properties of SFN, but especially the emerging anti-CSCs effects of this natural product and its potential to be used with conventional antineoplastic drugs in the clinical setting.

18.
Talanta ; 257: 124345, 2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-36791595

RESUMEN

Non-transferrin-bound iron (NTBI) is a group of circulating toxic iron forms, which occur in iron overload or health conditions with dysregulation of iron metabolism. NTBI is responsible for increased oxidative stress and tissue iron loading. Despite its relevance as a biochemical marker in several diseases, a standardized assay is still lacking. Several methods were developed to quantify NTBI, but results show high inter-method and even inter-laboratory variability. Thus, the development of a consistent NTBI assay is a major goal in the management of iron overload and related clinical conditions. In this work, a micro sequential injection lab-on-valve (µSI-LOV) method in a solid phase spectrophotometry (SPS) mode was developed for the quantification of NTBI, using a bidentate 3,4-hydroxypyridinone (3,4-HPO) ligand anchored to sepharose beads as a chromogenic reagent. To attain SPS, the functionalized beads were packed into a column in the flow cell, and the analyte, NTBI retained as iron (III), formed a colored complex at the beads while eliminating the sample matrix. The dynamic concentration range was 1.62-7.16 µmol L-1 of iron (III), with a limit of detection of 0.49 µmol L-1 and a limit of quantification of 1.62 µmol L-1. The proposed µSI-LOV-SPS method is a contribution to the development of an automatic method for the quantification of the NTBI in serum samples.


Asunto(s)
Sobrecarga de Hierro , Hierro , Humanos , Hierro/metabolismo , Transferrina/metabolismo , Suero/metabolismo , Espectrofotometría
19.
Health Promot Pract ; 24(5): 886-894, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-36412246

RESUMEN

Latino day laborers (LDLs) are at a high risk for injury and accidents at work and have limited socioeconomic resources to deal with their consequences. While little is known about LDLs' perceptions of their own vulnerability at the workplace, less is known about the strategies they adopt to confront these risks. The purpose of this qualitative study was to assess LDLs' perceptions of their workplace dangers and to document the strategies they adopt and endorse to confront them. Guided by a participatory research approach, four focus groups stratified by age were conducted with 34 LDLs in Houston, Texas. Main focus group themes were identified using a combination of qualitative analysis methods involving a thematic analysis conducted by the interview team, LDL advisors, and bilingual Latino researchers. All participants were Latino males (mean age = 40), the majority reported having completed sixth grade or less (64.2%) and having lived in the United States for an average of 12.7 years. We described three categories of strategies to reduce risk for workplace injury generated by local LDLs (practical knowledge and job experience, interpersonal, and personal). These strategies should be explored and encouraged to assist in planning risk-reduction programs, presented in the voice and language of Latino "inside experts" with firsthand experience. The findings of the focus group suggest that LDLs already possess a broad repertoire of strategies to cope with risks at work that can be incorporated in safety programs for LDLs and other immigrant Latino workers.


Asunto(s)
Emigrantes e Inmigrantes , Conductas Relacionadas con la Salud , Hispánicos o Latinos , Salud Laboral , Adulto , Humanos , Grupos Focales , Texas , Estados Unidos , Lugar de Trabajo
20.
Polymers (Basel) ; 16(1)2023 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-38201685

RESUMEN

An enormous interest in the development of efficient protocols for cellulose extraction has been demonstrated in the last few years, although usually based on non-sustainable chemical and thermal approaches. In this work, we propose a new and more sustainable method for cellulose extraction from eucalyptus and pine tree wood waste products exclusively performed using microwave-assisted radiation. The methodology includes three main steps: (i) alkaline treatment; (ii) bleaching I, using H2O2; and (iii) bleaching II, an acidic treatment. Samples obtained in each step were characterized by Fourier-transform Infrared (FTIR) spectroscopy, powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). The results were compared with the structural and thermal profile of the starting materials, a commercially available microcrystalline cellulose and with an industrial paper pulp sample. Results confirmed that for both types of wood wastes, cellulose was retained during the extraction procedures and that the removal of hemicellulose and lignin was mainly achieved in the last step, as seen by the FTIR spectra and TGA curves. The developed protocol is innovative, as it constitutes an easy and quick approach for extracting cellulose from eucalyptus and pine tree wood waste. Mild chemical and thermal conditions are used during the three extraction steps (microwave irradiation, aqueous solutions, maximum of 120 °C in a total of 3 h). Moreover, environmentally friendly purification steps are applied based on the use of water and ethanol. This approach offers the possibility of a future scale-up study to potentially apply the developed protocol to the extraction of cellulose on an industrial scale.

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