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1.
BMC Public Health ; 24(1): 2438, 2024 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-39245744

RESUMEN

BACKGROUND: Ultraviolet (UV) radiation is the most important risk factor for skin cancer development. Sunlight is the main source of UV radiation in the general population. In addition, tanning beds are a source of artificial UV radiation. Since the incidence of skin cancer is increasing worldwide, it is necessary to monitor UV-related risk behaviors such as intentional indoor and outdoor tanning, as well as sun protection behavior in the general population and specific subgroups and settings. This is the aim of the National Cancer Aid Monitoring online (NCAM-online), a continuation and further development of the NCAM. METHODS: The NCAM-online is a longitudinal trend study consisting of four annual survey waves. Each year, 4,000 individuals aged 16-65 years living in Germany will be surveyed using online questionnaires. Each year, intentional indoor and outdoor tanning will be assessed. In addition, varying specific topics regarding skin cancer prevention, such as the utilization of skin cancer screening, will be addressed in the questionnaires. DISCUSSION: The findings of the NCAM-online will provide an important basis for the German Cancer Aid and Working Group on Dermatologic Prevention (Arbeitsgemeinschaft Dermatologische Prävention, ADP) to develop targeted prevention campaigns and projects aimed at preventing skin cancer. The explorative nature of the NCAM-online allows for the identification of new potential starting points for prevention and education. In addition, the longitudinal design allows for a description of the trend in the prevalence of intentional tanning. For tanning bed use, representative trend data from 2012 are available for Germany, to which NCAM-online will add annual data until 2027.


Asunto(s)
Neoplasias Cutáneas , Rayos Ultravioleta , Humanos , Persona de Mediana Edad , Alemania/epidemiología , Adulto , Rayos Ultravioleta/efectos adversos , Adolescente , Anciano , Neoplasias Cutáneas/prevención & control , Neoplasias Cutáneas/epidemiología , Masculino , Femenino , Adulto Joven , Estudios Longitudinales , Encuestas y Cuestionarios , Baño de Sol/estadística & datos numéricos , Internet , Conductas Relacionadas con la Salud , Neoplasias Inducidas por Radiación/prevención & control , Neoplasias Inducidas por Radiación/epidemiología , Factores de Riesgo
2.
Collagen Leather ; 6(1): 28, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39246408

RESUMEN

Vegetable tannins are environmentally friendly tanning agents. However, they generally impart a dark colour to the tanned leather and highly contribute to the organic load in wastewaters. In this study, we employed a purification protocol separately on chestnut tannin (CT) and sulfited quebracho tannin (QT) to obtain the purified fractions (PCT and PQT). These samples were characterised by GPC, 1H NMR, 13C NMR, FT-IR, and HPLC-DAD techniques and applied for tanning tests. Through the purification process, non-tannin components and smaller molecules such as gallic acid, glucopyranose, and catechin were effectively removed from CT and QT, which consequently led to the reduced moisture content, pH value, and lighter colour of purified fractions. The crust leathers processed with PCT and PQT showed desirable light shades. Moreover, the organic loads in PCT and PQT tanning wastewater were reduced by 13.5% and 19.1%, respectively, when compared to those in traditional CT and QT tanning wastewater. Additionally, the physical and mechanical characteristics of crust leathers processed with PCT and PQT were comparable to those processed with CT and QT. Thus, purification of vegetable tannins may serve as a feasible strategy for producing light-colored vegetable-tanned leather while minimizing organic pollutant discharge during the vegetable tanning process. Supplementary Information: The online version contains supplementary material available at 10.1186/s42825-024-00171-9.

3.
Heliyon ; 10(16): e36263, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39253274

RESUMEN

Cross-linking, also called tanning, improves mechanical properties of leather and also increases its enzymatic and thermal stability. As a final product, leather has an ultimate tensile strength (σ) of 8-25 MPa and an elongation at break (ε) of >30 %. Mycelium-based materials are a sustainable alternative to leather. Here, the effect of cross-linkers was assessed on mechanical properties of Schizophyllum commune mycelium sheets. To this end, glutaraldehyde and N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide (EDC) were used as well as extracts of Ligustrum vulgare leaves, and bark of Acacia mearnsii and Caesalpinia spinosa. Untanned sheets had a σ of 7.8 MPa and an ε of 15.2 %, while the best overall combination of strength and elasticity was obtained with 0.1 % glutaraldehyde with a σ of 11.1 MPa and an ε of 14.6 %. Cross-linking also increased enzymatic stability and reduced mycelial water absorption but did not result in increased thermal stability. Fourier transform infrared spectroscopy (FTIR), 1D nuclear magnetic resonance spectroscopy (NMR), and amino acid analysis showed that glutaraldehyde bound both protein amino groups and polysaccharide hydroxyl groups by forming Schiff bases and acetals, respectively. Together, synthetic and vegetable cross-linkers can be used to obtain mycelium materials with leather-like tensile strength.

4.
Heliyon ; 10(17): e36270, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-39263112

RESUMEN

This study investigated the viability of locally available organic sources of Azadirachta indica leaf as vegetable tannin agent in leather processing to promote green leather manufacturing. Leather tanned with Azadirachta indica leaf powder (NPT), extract (NET) and conventional vegetable tanned leather (CVT) was characterized with FTIR, DLS, HPLC, DSC, TGA, and SEM. Total soluble solid, pH, tannin content, and tanning strength of Azadirachta indica leaf extract were found to be 24 %, 4.81, 12.34 % and 1.81 respectively. Moisture content, fat content, and water-soluble content of Azadirachta indica leaf extract tanned leather (NET) were 12.26 %, 10.8 % and 7.2 % respectively. The shrinkage temperature, tensile strength, stitch tear strength, grain crack load, and finished film bond strength of NET leather were 86 °C, 282.52 kg/cm2, 139.53 kg/cm, 24 kg, and 414 g/cm respectively. NET leather exhibited better anti-microbial sensitivity against E. coli, S. aureus, and P. aeruginosa than NPT and NET leather. Overall, the experimental results of this study indicate the A. indica leaf could serve as a prime renewable tanning agent, substituting hazardous chromium and imported conventional vegetable tannin chemicals in leather manufacturing. Thus, developed A. indica leaf tannin material from plant sources could provide sustainable leather production, contributing to eco-friendly and viable green leather processing options.

6.
J Environ Manage ; 366: 121894, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39032261

RESUMEN

The leather manufacturing industry is increasingly embracing chrome-free tanning methods to promote environmental sustainability. However, the transition to chrome-free tanning systems presents a notable obstacle: the incompatibility of traditional anionic wet finishing materials with chrome-free tanned leather due to differences in surface electrical behavior. Herein, an amphoteric polymer, referred to P(AA-co-DMAEMA-co-DA), was synthesized through a simple one-step free radical copolymerization using acrylic acid (AA), dimethylaminoethyl methacrylate (DMAEMA), and dodecyl acrylate (DA). Notably, the isoelectric point of P(AA-co-DMAEMA-co-DA) is 7.7, which contributes to improving the leather's positive electric property and enhancing the binding between the amphoteric polymer fatliquors (APF) and collagen fiber. The APF achieves a remarkable absorption rate of 96.2% and a dyeing uptake rate of 94.3% for anionic dyes, resulting in a uniformly bright surface color of the dyed leather and further significantly reducing the dye usage. Overall, the comprehensive properties of APF align with the electrical origins of organic chrome-free tanning leather, exhibiting a pronounced fatliquoring effect while reducing the dye content in the waste liquor. This contribution holds promise for advancing chrome-free tanning technology toward greener environmental practices.


Asunto(s)
Polímeros , Curtiembre , Polímeros/química , Colorantes/química , Acrilatos/química
7.
Environ Res ; 260: 119580, 2024 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-38992757

RESUMEN

Physicochemical and toxicological characterization of leather tanning wastewater has been widely documented. However, few reports have examined the response of denitrification N2 and N2O emissions in riparian sediments of tannery wastewater-receiving rivers. In this study, 15N-nitrate labeling was used to reveal the effects of tanning wastewater on denitrification N2 and N2O emission in a wastewater-receiving river (the old Mang River, OMR). OMR riparian sediments were highly polluted with total organic carbon (93.39 mg/kg), total nitrogen (5.00 g/kg) and heavy metals; specifically, Cr, Zn, Cd, and Pb were found at concentrations 47.3, 5.8, 1.6, 4.3, and 2.8 times that in a nearby parallel river without tanning wastewater input (the new Mang River, NMR), respectively. The denitrification N2 emission rates (0.0015 nmol N · g-1 h-1) of OMR riparian sediments were significantly reduced by 2.5 times compared with those from the NMR (p < 0.05), but the N2O emission rates (0.31 nmol N · g-1 h-1) were significantly increased (4.1 times, p < 0.05). Although the dominant nitrogen-transforming bacteria phylum was Proteobacteria in the riparian sediments of both rivers, 11 nitrogen-transforming bacteria genera in the OMR were found to be significantly enriched; five of these were related to pollutant degradation based on linear discriminant analysis (LDA >3). The average activity of the electron transport system in the OMR was 6.3 times lower than that of the NMR (p < 0.05). Among pollution factors, heavy metal complex pollution was the dominant factor driving variations in N2O emissions, microbial community structure, and electron transport system activity. These results provide a new understanding and reference for the treatment of tanning wastewater-receiving rivers.


Asunto(s)
Sedimentos Geológicos , Nitrógeno , Ríos , Curtiembre , Aguas Residuales , Ríos/microbiología , Ríos/química , Aguas Residuales/microbiología , Aguas Residuales/química , Aguas Residuales/análisis , Sedimentos Geológicos/microbiología , Sedimentos Geológicos/química , Nitrógeno/análisis , Contaminantes Químicos del Agua/análisis , Bacterias , Desnitrificación , Óxido Nitroso/análisis
8.
AJPM Focus ; 3(4): 100241, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38993711

RESUMEN

Introduction: Indoor tanning is a major modifiable risk factor in the development of both melanoma and nonmelanoma skin cancers. Investigation of behavior-altering interventions is an area of active research. As with other preventive measures, screening of high-risk populations can be an important aspect of a multimodality public health intervention. This study sought to further the limited understanding of indoor tanning screening practices in the primary care setting. Methods: Physicians practicing within the scope of primary care in the northeast were surveyed in 2022 on practice patterns around the frequency of indoor tanning screening, barriers encountered with implementing screening, and actions taken with a positive screen. Research methodology adhered to the Joanna Briggs Institute critical appraisal checklist. Results: Of 26 primary care physicians, only 7.7% routinely screened for indoor tanning. Barriers identified included time limitations (76.9%) and prioritization of other health concerns (96.2%). All primary care physicians (100%) reacted to reports of indoor tanning with an intervention, most commonly counseling on the risks of indoor tanning (92.6%). Conclusions: This data suggest that screening for indoor tanning use could be improved. The authors recommend the incorporation of a standardized screening question regarding indoor tanning in intake forms.

9.
Sustain Chem Environ ; 6: 100092, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38947873

RESUMEN

Untreated tannery wastewater contains a large amount of toxic metals, dyes, and other pollutants, which pose adverse effects on the ecosystem and public health. In this work, a calcium alginate-poly vinyl alcohol-graphene oxide (CA-PVA-GO) composite was prepared to remove metals and dyes, particularly Cr(Ⅲ) and CI acid violet 54 (AV54) dye, from tannery wastewater. FESEM, FTIR, and XRD analyses were applied to characterize the GO and CA-PVA-GO. Different operational variables, viz. pH (3.0-5.5 for Cr(III) and 2-7 for dye), dosage (0.164-2.46 g/L), contact time (10-60 min), initial concentration (39, 65, 98, and 201 ppm for Cr(III) and 21.5, 38.5, 54.5, and 61.75 ppm for dye), and temperature (298, 308, 318, and 328 K) were studied to evaluate the efficiency of the CA-PVA-GO composite. The optimum conditions for Cr(Ⅲ) and AV54 dye adsorption were found to be pH (5.0 and 3.0), dosage (0.82 g/L for both), and time (45 and 60 min), respectively, with 35.35 ± 1.43% and 84.63 ± 2.54% removal efficiency. The experimental data was analyzed through the Langmuir and Freundlich isotherms. The maximum adsorption capacity (qm) was observed at 173.01 and 74.68 mg/g for Cr(Ⅲ) and AV54 dye, respectively. The pseudo-second-order kinetic model was fitted better (R2 = 0.981, 0.995, 0.92, and 0.995) than first-order for AV54 dye adsorption. Thermodynamic analyses revealed that the Cr(Ⅲ) and AV54 dye adsorption processes were spontaneous and exothermic. The value of Gibbs free energy (ΔG) for Cr(III) adsorption was obtained at -7.433, -4.508, -2.626, and -1.311 kJ/mol, whereas it was -5.178, -4.867, -4.628, and -4.555 kJ/mol for dye. The values of ΔH and ΔS were -67.257 and -0.198 kJ/mol for Cr(III) and -10.852 and -0.019 kJ/mol for the dye removal. The regenerated CA-PVA-GO composite was reused successfully. Different physicochemical parameters, viz., concentration, pH, TDS, EC, BOD5, and COD of chrome tanning and dyeing effluents, were analyzed before and after the adsorption. The results of chromium and dye removal from tannery wastewater were 53.18% and 93.91%, revealing that the developed eco-friendly CA-PVA-GO composite could be an operative adsorbent for tannery wastewater treatment and possibly scaled up to an industrial level.

10.
Heliyon ; 10(11): e31787, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38845927

RESUMEN

Utilization of vegetable tannins in leather processing is one of the convenient solutions to protect the environment pollution. Herein, the banana bunch and syrup of banana stem are utilized to prepare an ecofriendly tanning agent. The yield of banana bunch extraction efficiency is found 69.80 %. FT-IR analysis confirmed the presence of condensed type tanning component owing to the bearing of different polyphenolic groups. The content of tannins in extracted banana bunch and stem syrup is 3.13 % and 2.6 %, respectively. The phenolic content in the banana bunch extract is determined to be 1332.37 mg GAE/100g of dried weight and in syrup was 873.92 mg GAE/100g of dried weight. This makes it possible to be used as vegetable tanners. The extracted bunch and syrup are applied to re-tan leather and compared with conventionally used vegetable tanning agent (quebracho) in parallel. Tensile strength, tear strength and elongation percentage for the extracted banana bunch and syrup are obtained at 23.84 N/mm2, 68.26 N/mm, 47.07 %, and 22.97 N/mm2, 68.38 N/mm, 40.70 %, respectively. The softness is found 1.41 for the extracted bunch and 2.01 for the syrup. The grain crack load, distension at grain crack, strength at ball burst, distension at ball burst are 246.86 N, 13.24 mm, 530.77 N, 24.54 mm for banana stem syrup and 338.77 N, 13.42 mm, 460.65 N, 29.08 mm for bunch extract, respectively. The shrinkage temperatures recorded for banana bunch extract, syrup and Quebracho (control trial) tannins tanned leather samples are 76.5 °C, 75 °C and 84 °C subsequently. The flexing endurance of the bunch extract and syrup revealed acceptable values that are less than 4. Moreover, the bunch extract tanned leather shows greater thermal stability and for syrup it is similar with the quebracho tanned leather. All the results are satisfactory compared to the control trial. Finally, tanned leather is evaluated to assess the possibility of the newly developed tannin which proves its efficiency as a potential source of tanning material for the leather industry.

11.
Membranes (Basel) ; 14(6)2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38921503

RESUMEN

This paper presents the basic assumptions of the concept of a new technology for the valorisation of chromium tannery waste. It assumes the use of an integrated system of the thermal pressure hydrolysis process and membrane filtration techniques for the recovery of chromium compounds and the use of a separated organic matter during anaerobic fermentation. According to the assumptions of the developed technological concept, at the first stage, the crushed mixture of chromium tannery waste is decomposed in the process of thermal pressure hydrolysis using appropriate process conditions in an alkaline environment. Then, the liquid product of this process (the so-called hydrolysate) is processed using centrifugal force separation and ultrafiltration. Such activities enable the recovery of chromium compounds for rawhide currying and concentration of organic matter (fats, proteins) with energy potential. Research carried out under conditions similar to real operating conditions proved that chromium compounds recovered from waste can be successfully used in the processing of cowhides intended for the production of footwear. The industrial implementation of the developed technology for valorising chromium tannery waste would enable the transition from a linear to a circular economy.

12.
Trop Anim Health Prod ; 56(5): 189, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38864934

RESUMEN

The aim was to evaluate the quality of the sheep skin of different sex classes submitted to different levels of feed restriction. Sheep without defined racial pattern of different sex classes (15 non-castrated males, 15 castrated males and 15 females), with initial body weight of 18.1 ± 0.4 kg and mean age of 90 days were distributed in a factorial 3 × 3, with three sex classes and 3 levels of feed restriction (ad libitum intake and restricted intake at 70 and 80%), with 5 repetitions. After slaughter, the skins were collected for physical-mechanical tests. The effect of the sex classes x levels of dietary restriction interaction was observed for transverse thickness and longitudinal rupture elongation (p < 0.05). Animals fed ad libitum had greater longitudinal transverse thickness (p < 0.05). Animals fed ad libitum and 70% feed restriction showed greater transverse elongation at break (p < 0.05). As for the difference between sex classes in the transverse thickness variable for tearing strength, the interaction sex classes x levels of feed restriction for transverse thickness, longitudinal thickness, transverse tearing strength and longitudinal tearing strength occurred (p < 0.05). Feed restriction reduces the physical quality of the skin of sheep of different sex classes, and the use of castrated male sheep in positive energy balance is recommended to obtain leather with greater thickness, longitudinal rupture elongation and transverse tear strength.


Asunto(s)
Piel , Animales , Masculino , Femenino , Oveja Doméstica/fisiología , Oveja Doméstica/crecimiento & desarrollo , Factores Sexuales , Privación de Alimentos/fisiología , Alimentación Animal/análisis , Ovinos/fisiología , Ovinos/crecimiento & desarrollo , Orquiectomía/veterinaria
13.
Phenomics ; 4(2): 138-145, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38884062

RESUMEN

Ultraviolet radiation (UVR) can induce erythema and tanning responses with strong diversity within and between populations, but there were no precise method for evaluating the variation in these responses. In this study, we assessed the time course of ultraviolet (UV)-induced responses based on the erythema index (EI) and melanin index (MI) over 14 consecutive days in a pilot cohort study (N = 31). From safety evaluations, we found that no skin blisters occurred at a UV dosage of 45 mJ/cm2, but there were significant skin reactions. Regardless of UV dosage, the measurements and variances of EI peaked on day 1 after UV irradiation, and those of MI peaked on day 7. Dose-response curves, including erythema dose-response (EDR) and melanin dose-response (MDR), could measure UV-induced phenotypes sensitively but more laboriously. As an alternative, we directly represented the UV-induced erythema and tanning responses using the erythema increment (ΔE) and melanin increment (ΔM). We found that ΔE and ΔM at 45 mJ/cm2 significantly correlated with erythema dose-response (EDR) (R 2 > 0.9) and melanin dose-response (MDR) (R 2 > 0.9), respectively. Therefore, ΔE and ΔM on day 1 and day 7 after UV irradiation at a dosage of 45 mJ/cm2 might be ideal alternative measures for assessing individual erythema and tanning responses. Then, a second cohort (N = 664) was recruited to validate the UV-induced phenotypes, and, as expected, the results of the two cohorts were in agreement. Therefore, we developed a simplified and precise method to quantify the UV-induced erythema response and tanning ability for the Han Chinese population. Supplementary Information: The online version contains supplementary material available at 10.1007/s43657-023-00105-1.

14.
Arch Dermatol Res ; 316(6): 281, 2024 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-38796657

RESUMEN

Exposure to solar ultraviolet (UV) radiation and use of UV-emitting tanning devices are known risk factors for skin cancer. Few studies have explored the interaction between these risk factors, namely how the risk of skin cancer increases among those who both have been exposed to high levels of natural sunlight and regularly use tanning beds. Nurses' Health Study II followed 116,430 women, aged 25-42, from 1991 to 2011. Cumulative average UV exposure was based on participants' residences at follow-up periods. History of severe sunburn during ages 15-20 was used as a proxy for early-life sunlight exposure. Tanning bed use in early life data was collected. Participants reported melanoma, basal cell carcinoma (BCC), and squamous cell carcinoma (SCC) diagnoses. We built multivariable Cox regression models to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for risk of skin cancer associated with joint effects of sunlight exposure and tanning bed use. Participants with high sunlight exposure and tanning bed use during high school/college had an increased risk of BCC (HR = 1.53, 95% CI 1.37-1.71, Pinteraction=0.01; vs. low sun exposure and no tanning bed use). Participants with a history of severe sunburns and tanning bed use during high school/college were at increased risk of BCC (HR = 1.62, 95% CI 1.47-1.79, Pinteraction=0.02; vs. no sunburns and no tanning bed use). No significant interactions were found between sunlight exposure and tanning bed use on SCC and melanoma risk. We found significant interactions between sunlight exposure and tanning bed use on the risk of BCC.


Asunto(s)
Carcinoma Basocelular , Carcinoma de Células Escamosas , Melanoma , Neoplasias Cutáneas , Baño de Sol , Luz Solar , Humanos , Femenino , Neoplasias Cutáneas/etiología , Neoplasias Cutáneas/epidemiología , Carcinoma Basocelular/epidemiología , Carcinoma Basocelular/etiología , Melanoma/etiología , Melanoma/epidemiología , Estudios Prospectivos , Carcinoma de Células Escamosas/epidemiología , Carcinoma de Células Escamosas/etiología , Adulto , Luz Solar/efectos adversos , Factores de Riesgo , Baño de Sol/estadística & datos numéricos , Quemadura Solar/epidemiología , Rayos Ultravioleta/efectos adversos , Modelos de Riesgos Proporcionales
15.
Int J Womens Dermatol ; 10(2): e128, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38572264

RESUMEN

Background: Exposure to ultraviolet radiation is a leading risk factor for developing all types of skin cancer. In the United States, an estimated 7.8 million young adults engage in indoor tanning. Objective: Here, it is hypothesized that certain populations of students at undergraduate universities, namely sorority members, have a greater frequency of tanning bed usage than other groups of students and that regardless of sorority status, the most important motivating factor will be the intent to enhance one's appearance. Methods: Undergraduate students at 2 state-funded universities were recruited for participation in this institutional review board-exempt survey via distribution to e-mail addresses and social media accounts affiliated with student organizations/clubs. Results: Among all respondents, the most common motivating factors for tanning bed use were the perception of improved self-appearance and boosted self-confidence. Female sorority members were more likely to use tanning beds and also more likely to report being motivated by enhanced appearance and self-confidence, than their female counterparts who were not sorority members. Limitations: The sample size (n = 321) and population of this study allows data to only be generalizable to surrounding states with similar demographics. The findings of this study are subject to recall bias as the data is self-reported. Conclusion: Tanning bed use remains a popular practice among young people. Understanding motivations for tanning bed use among populations at increased risk of partaking in this behavior allows for educating these groups on the risks associated with ultraviolet radiation exposure. It is crucial that providers continue to promote skin health and take steps to dissuade detrimental practices and possible habit-forming behaviors at the individual and state levels.

16.
Int J Biol Macromol ; 268(Pt 1): 131858, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38670203

RESUMEN

In this study, proteolytic bacteria, particularly Pseudomonas aeruginosa strain SM4 (OQ349573), were isolated from tannery solid waste dumping yard soil and employed to produce extracellular protease enzymes. The bacteria exhibited optimal growth after 30 h of incubation at 37 °C and pH 7. Under conditions of 55 °C, pH 8, and a substrate concentration of 2 %, the crude enzyme displayed its highest activity at 105 UmL-1. Notably, the produced crude enzyme showed no discernible inhibitory effects on detergents, metal salts, or organic solvents. Application of the crude protease at concentrations of 3 % and 2 % in chrome tanning of goatskins (GS) and cowhides (CH), respectively, yielded significant reductions of 35 % and 30 % in chromium and other post-tanning chemicals compared to conventional processes. Despite the 30 to 35 % reduction in tanning and post-tanning chemicals, the uptake of chrome and associated chemicals by crust leather was higher than observed in conventional processes. Chromium content analysis of the effluent revealed an 81 % reduction during piloting in real industrial operations, accompanied by reductions of about 46 % in BOD and COD pollution loads. The finished leather obtained from the enzymatic process exhibited superior mechanical properties, including higher tensile strengths (210 and 195 kg cm-2), stitch tear (92 and 165 kg cm-1), grain crack load (28 and 32 kg), and distension (73 and 62 mm) for GS and CH, respectively, surpassing or closely aligning with standard values and those obtained in conventional processes.


Asunto(s)
Péptido Hidrolasas , Curtiembre , Péptido Hidrolasas/metabolismo , Pseudomonas aeruginosa/efectos de los fármacos , Concentración de Iones de Hidrógeno , Animales , Biodegradación Ambiental , Cromo
17.
Int J Biol Macromol ; 268(Pt 2): 131682, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38643914

RESUMEN

This study aimed to prepare a new bio-based chromium-free tanning agent. The green epoxide monocase ethylene glycol diglycidyl ether (EGDE) was grafted with tannic acid (TA) derived from natural plant using the one-pot method to synthesize new plant polyphenol-derived tannic acid-based chromium-free tanning agents (TA-EGDE) with abundant terminal epoxides. FTIR, 1H NMR, XPS, GPC, SEM, and other analytical techniques were used to characterize tanning agents. These consequences manifested that EGDE was successfully grafted with the phenol hydroxyl group of TA. The epoxide value of TA-EGDE showed a tendency to increase and then decrease with increasing EGDE dosage, and the epoxide value of TA-EGDE-2 attained a maximum of 0.262 mol/100 g. GPC analysis showed that the formula weight of the prepared TA-EGDE was partially distributed above 5000 Da. The tanning experiment demonstrated that the shrinkage temperatures (Ts) of the TA-EGDE-tanned leathers were all higher than 81.5 °C. Compared with the traditional commercial chromium-free tanning agent (F-90, TWS), TA-EGDE-tanned leathers exhibited higher Ts and better mechanical properties. The TA-EGDE prepared in this study not only has ecological environmental protection but also provides finished leather with good moisture, heat resistance, and mechanical properties.


Asunto(s)
Polifenoles , Curtiembre , Taninos , Taninos/química , Polifenoles/química , Cromo/química
18.
JMIR Res Protoc ; 13: e56562, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38502173

RESUMEN

BACKGROUND: Rates of melanoma have increased dramatically in the United States over the past 25 years, and it has become among the most prevalent cancers for young adult women. Intentional skin tanning leads to a pattern of intense and intermittent UV radiation exposure that is associated with increased risk of melanoma. Frequent tanning is most common among young women and is linked to a variety of sociocultural pressures that negatively impact body image and drive appearance control behaviors. Unfortunately, there are no established interventions designed for frequent tanners. This intervention addresses this gap with unique content informed by body image and acceptance-based interventions. The intervention is delivered using Facebook secret groups, an approach designed to support behavior change and ensure scalability. OBJECTIVE: This study aims to describe the rationale and methodology of a randomized controlled trial of a melanoma prevention program targeting young women engaged in frequent indoor or outdoor UV tanning. METHODS: Participants are women aged 18-25 years who report high-risk tanning (ie, at least 10 indoor tanning sessions in the past 12 months or 10 outdoor sessions in the previous summer). After recruitment and screening, participants completed a baseline survey and were randomly assigned to receive the intervention or an attention-matched control condition. Both conditions were 8-week-long Facebook groups (approximately 25 members each) with daily posting of content. Follow-up surveys are administered at 3, 8, and 18 months after baseline. The primary trial outcome is the combined number of indoor and outdoor tanning sessions reported at the 8-month follow-up. Hypothesized intervention mediators are assessed at the 3-month follow-up. RESULTS: This project was funded by a National Cancer Institute award (R01 CA218068), and the trial procedures were approved by the University of Kentucky Institutional Review Board in February 2020. Trial recruitment and enrollment occurred in 6 waves of data collection, which started in February 2022 and closed in May 2023. The study is closed to enrollment but remains open for follow-ups, and this protocol report was prepared before data analyses. As of February 2024, all participants have completed the 8-month follow-up assessment, and data collection is scheduled to close by the end of 2024 after the collection of the 18-month follow-up. CONCLUSIONS: This trial will contribute unique knowledge to the field of skin cancer prevention, as no fully powered trials have examined the efficacy of an intervention designed for frequent indoor or outdoor tanning. The trial may also contribute evidence of the value in translating principles of body image and acceptance-based interventions into the field of skin cancer prevention and beyond. If successful, the use of the Facebook platform is intended to aid in dissemination as it provides a way to embed the intervention into individuals' everyday routines. TRIAL REGISTRATION: ClinicalTrials.gov NCT03441321; https://clinicaltrials.gov/study/NCT03441321. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/56562.

19.
Int J Biol Macromol ; 265(Pt 2): 131133, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38537851

RESUMEN

The low chrome uptake by collagen in the conventional tanning process leads to the pollution of the wastewater. Due to environmental concerns, leather scientists are already searching for innovative ways to produce pre-tanning agents as a high exhaustion chrome tanning auxiliary. Herein, a novel kind of pre-tanning agent is engineered by converting carboxymethyl cellulose (CMC) to oxidized carboxymethyl cellulose (OCMC) via the hydrogen peroxide process. FT-IR and carboxyl content analysis demonstrated the increase in carboxyl content after oxidation. After that, the obtained OCMC was utilized as a pre-tanning agent, resulting in a high exhaustion of chrome (92.76 %) which is 27.76 % more than conventional chrome tanning (65 %), and the amount of chrome in wastewater reduced to 7.24 %. The hydrothermal stability of wet-blue increased by increasing the uptake of chrome (Ts = 118 °C). The obtained crust leather represented excellent mechanical properties (Tensile strength: 305.68 kg/cm2; tear strength: 50 kg/cm) and desirable organoleptic properties. The environmental analysis signifies a significant step towards a cleaner and sustainable tanning process (COD = 1600, BOD5 = 560 mg/L) compared to the conventional chrome tanning process. Consequently, the obtained results offer a green pre-tanning agent to meet the requirements of the sustainable development of the leather industry.


Asunto(s)
Carboximetilcelulosa de Sodio , Curtiembre , Peróxidos , Espectroscopía Infrarroja por Transformada de Fourier , Aguas Residuales , Residuos Industriales/análisis , Cromo
20.
JMIR Dermatol ; 7: e54052, 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38437006

RESUMEN

BACKGROUND: Indoor tanning is a preventable risk factor for skin cancer. Statewide shutdowns during the COVID-19 pandemic resulted in temporary closures of tanning businesses. Little is known about how tanners reacted to losing access to tanning businesses. OBJECTIVE: This study aimed to analyze Twitter (subsequently rebranded as X) chatter about indoor tanning during the statewide pandemic shutdowns. METHODS: We collected tweets from March 15 to April 30, 2020, and performed a directed content analysis of a random sample of 20% (1165/5811) of tweets from each week. The 2 coders independently rated themes (κ=0.67-1.0; 94%-100% agreement). RESULTS: About half (589/1165, 50.6%) of tweets were by people unlikely to indoor tan, and most of these mocked tanners or the act of tanning (562/589, 94.9%). A total of 34% (402/1165) of tweets were posted by users likely to indoor tan, and most of these (260/402, 64.7%) mentioned missing tanning beds, often citing appearance- or mood-related reasons or withdrawal. Some tweets by tanners expressed a desire to purchase or use home tanning beds (90/402, 22%), while only 3.9% (16/402) mentioned tanning alternatives (eg, self-tanner). Very few tweets (29/1165, 2.5%) were public health messages about the dangers of indoor tanning. CONCLUSIONS: Findings revealed that during statewide shutdowns, half of the tweets about indoor tanning were mocking tanning bed users and the tanned look, while about one-third were indoor tanners reacting to their inability to access tanning beds. Future work is needed to understand emerging trends in tanning post pandemic.

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