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1.
Carbohydr Polym ; 332: 121924, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38431399

RESUMO

Sustainable recovery of chitin and its derivatives from shellfish waste will be achieved when the industrial production of these polymers is achieved with a high control of their molecular structure, low costs, and acceptable levels of pollution. Therefore, the conventional chemical method for obtaining these biopolymers needs to be replaced or optimized. The goal of the present review is to ascertain what alternative methods are viable for the industrial-scale production of chitin, chitosan, and their oligomers. Therefore, a detailed review of recent literature was undertaken, focusing on the advantages and disadvantages of each method. The analysis of the existing data allows suggesting that combining conventional, biological, and alternative methods is the most efficient strategy to achieve sustainable production, preventing negative impacts and allowing for the recovery of high added-value compounds from shellfish waste. In conclusion, a new process for obtaining chitinous materials is suggested, with the potential of reducing the consumption of reagents, energy, and water by at least 1/10, 1/4, and 1/3 part with respect to the conventional process, respectively.


Assuntos
Quitosana , Quitosana/química , Quitina/química , Frutos do Mar , Polímeros
2.
Microorganisms ; 11(6)2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37375098

RESUMO

Rahnella aquatilis AZO16M2, was characterized for its phosphate solubilization capacity to improve the establishment and survival of Musa acuminata var. Valery seedlings under ex-acclimation. Three phosphorus sources (Rock Phosphate (RF), Ca3(PO4)2 and K2HPO4) and two types of substrate (sand:vermiculite (1:1) and Premix N°8) were selected. The factorial analysis of variance (p < 0.05) showed that R. aquatilis AZO16M2 (OQ256130) solubilizes Ca3(PO4)2 in solid medium, with a Solubilization Index (SI) of 3.77 at 28 °C (pH 6.8). In liquid medium, it was observed that R. aquatilis produced 29.6 mg/L soluble P (pH 4.4), and synthesized organic acids (oxalic, D-gluconic, 2-ketogluconic and malic), Indole Acetic Acid (IAA) (33.90 ppm) and siderophores (+). Additionally, acid and alkaline phosphatases (2.59 and 2.56 µg pNP/mL/min) were detected. The presence of the pyrroloquinoline-quinone (PQQ) cofactor gene was confirmed. After inoculating AZO16M2 to M. acuminata in sand:vermiculite with RF, the chlorophyll content was 42.38 SPAD (Soil Plant Analysis Development). Aerial fresh weight (AFW), aerial dry weight (ADW) and root dry weight (RDW) were superior to the control by 64.15%, 60.53% and 43.48%, respectively. In Premix N°8 with RF and R. aquatilis, 8.91% longer roots were obtained, with 35.58% and 18.76% more AFW and RFW compared with the control as well as 94.45 SPAD. With Ca3(PO4)2, values exceeded the control by 14.15% RFW, with 45.45 SPAD. Rahnella aquatilis AZO16M2 favored the ex-climatization of M. acuminata through improving seedling establishment and survival.

3.
PLoS One ; 17(9): e0275190, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36166452

RESUMO

BACKGROUND: Motor vehicle crashes remain a leading cause of death among young adults (ages 18-25) in the United States. Many drivers implicated in these crashes are under the influence of alcohol, cannabis, or the simultaneous use of alcohol and cannabis. Extremely limited research has assessed impaired driving behaviors and their predictors at the daily level. Perceived norms and motives to use substances have empirical support suggesting they may impact impaired driving-related behavior. Novel approaches to assess these associations at the daily level are needed and may inform future intervention and prevention programs. OBJECTIVE: The goal of the current study is to utilize electronic daily assessments to assess driving under the influence of alcohol, cannabis, or simultaneous use and riding with a driver impaired by these substances to assess variability and predictors of these impaired driving-related behaviors at the daily level. This present manuscript details a protocol, measures, and a plan of analyses to assess how within-person differences in perceived norms and motives to use are associated with the likelihood of engaging in impaired driving-related behaviors. METHODS: Participants include young adults in Washington State who report simultaneous use in the past month and either driving under the influence of alcohol, cannabis, or simultaneous use, or riding with a driver under the influence of both substances in the past 6 months. Individuals who verify their identity and meet eligibility requirements will complete a baseline assessment after which they will be scheduled for training on the daily assessment procedure via Zoom. Next, they will be invited to complete daily surveys on Thursday, Friday, Saturday, and Sunday every other week for 6 months and a 6-month follow up assessment. Analyses will utilize multilevel models with days nested within individuals. RESULTS: The study is currently recruiting participants. A total of 192 participants have been recruited and 100 have completed the study protocol. Data collection is expected to be completed in Fall 2022. CONCLUSIONS: This study utilizes a novel design to assess impaired driving and predictors at the daily level among young adults at high risk of impaired driving-related behaviors. Findings will provide unique data that will shape the knowledge base in the field of social science and public health substance use research and that may be helpful for future prevention and intervention efforts on impaired driving.


Assuntos
Condução de Veículo , Cannabis , Dirigir sob a Influência , Acidentes de Trânsito/prevenção & controle , Adolescente , Adulto , Consumo de Bebidas Alcoólicas , Dirigir sob a Influência/prevenção & controle , Etanol , Humanos , Assunção de Riscos , Inquéritos e Questionários , Estados Unidos , Adulto Jovem
4.
Artigo em Inglês | MEDLINE | ID: mdl-35897403

RESUMO

Liver cirrhosis (LC) is an irreversible, chronic disease and constitutes the last clinical stage of many different liver diseases. The main cause of death is upper gastrointestinal bleeding caused by esophageal variceal rupture. We aim to depict the trend and estimate the morbimortality. For this, we conducted an ecological study and analyzed data from 2004-2016 using the public information provided by the Peruvian Ministry of Health (Ministerio de Salud del Perú, MINSA). Morbidity and mortality were presented according to 5-year groups. Regions were divided according to age quintiles for each studied year, and standardized morbidity and mortality rates were calculated for each natural geographic region; we found that LC-related morbidity per 100,000 people was 52.3 in 2004 and 117.9 in 2016. LC-related mortality had increased from 13.6 deaths per 100,000 people in 2004-2005 to 16.8 deaths per 100,000 people in 2015-2016. Morbidity showed an upward trend in Peru, especially in the departments of Callao, Ica, and Tumbes, whereas mortality showed an upward trend in the departments of Lambayeque, Ica, and Callao.


Assuntos
Hemorragia Gastrointestinal , Cirrose Hepática , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/epidemiologia , Peru/epidemiologia
5.
J Inorg Biochem ; 129: 119-26, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24103366

RESUMO

Superoxide is a potentially toxic by-product of cellular metabolism. We have addressed here the in vitro ability of complexes formed between copper(II) ions and various biologically-occurring disulfides (RSSR: oxidized glutathione, cystine, homocystine and α-lipoic acid) to react with superoxide. The studied complexes were found to react with superoxide (generated by a xanthine/xanthine oxidase system) at rate constants (kCu(II)-RSSR) close to 10(6)M(-1)s(-1), which are three orders of magnitude lower than that reported for superoxide dismutase (SOD) but comparable to that of several other copper-containing complexes reported as SOD mimetics. The interaction between the tested Cu(II)-RSSR and superoxide, led to the generation and recovery of concentrations of hydrogen peroxide and oxygen that were, respectively, below and above those theoretically-expected from a sole SOD mimetic action. Interestingly, oxygen was generated when the Cu(II)-RSSR complexes were directly incubated with hydrogen peroxide. Taken together, these results reveal that the Cu(II)-RSSR complexes not only have the capacity to dismutate superoxide but also to simultaneously act like catalase mimetic molecules. When added to superoxide-overproducing mitochondria (condition attained by its exposure to diclofenac), three of the tested complexes were able (2-4µM), not only to totally restore, but also to lower below the basal level the mitochondrial production of superoxide. The present study is first in reporting on the potential of Cu(II)-disulfide complexes to act as SOD and catalase like molecules, suggesting a potential for these types of molecules to act as such under physiological and/or oxidative-stress conditions.


Assuntos
Materiais Biomiméticos , Catalase , Cobre , Dissulfetos , Mitocôndrias/metabolismo , Superóxido Dismutase , Superóxidos/metabolismo , Animais , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Catalase/química , Catalase/farmacologia , Cobre/química , Cobre/farmacologia , Dissulfetos/química , Dissulfetos/farmacologia , Mitocôndrias/química , Ratos , Superóxido Dismutase/química , Superóxido Dismutase/farmacologia , Superóxidos/química
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