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1.
Ecotoxicol Environ Saf ; 266: 115533, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37806127

RESUMO

High environment ammonia (HEA) poses a deadly threat to aquatic animals and indirectly impacts human healthy life, while nutritional regulation can alleviate chronic ammonia toxicity. α-lipoic acid exhibits antioxidative effects in both aqueous and lipid environments, mitigating cellular and tissue damage caused by oxidative stress by aiding in the neutralization of free radicals (reactive oxygen species). Hence, investigating its potential as an effective antioxidant and its protective mechanisms against chronic ammonia stress in crucian carp is highly valuable. Experimental fish (initial weight 20.47 ± 1.68 g) were fed diets supplemented with or without 0.1% α-lipoic acid followed by a chronic ammonia exposure (10 mg/L) for 42 days. The results revealed that chronic ammonia stress affected growth (weight gain rate, specific growth rate, and feed conversion rate), leading to oxidative stress (decreased the activities of antioxidant enzymes catalase, superoxide dismutase, glutathione peroxidase; decreased total antioxidant capacity), increased lipid peroxidation (accumulation of malondialdehyde), immune suppression (decreased contents of nonspecific immune enzymes AKP and ACP, 50% hemolytic complement, and decrease of immunoglobulin M), impaired ammonia metabolism (reduced contents of Glu, GS, GSH, and Gln), imbalance of expression of induced antioxidant-related genes (downregulation of Cu/Zu SOD, CAT, Nrf2, and HO-1; upregulation of GST and Keap1), induction of pro-apoptotic molecules (transcription of BAX, Caspase3, and Caspase9), downregulation of anti-apoptotic gene Bcl-2 expression, and induction of endoplasmic reticulum stress (upregulation of IRE1, PERK, and ATF6 expression). The results suggested that the supplementation of α-lipoic acid could effectively induce humoral immunity, alleviate oxidative stress injury and endoplasmic reticulum stress, and ultimately alleviate liver injury induced by ammonia poisoning (50-60% reduction). This provides theoretical basis for revealing the toxicity of long-term ammonia stress and provides new insights into the anti-ammonia toxicity mechanism of α-lipoic acid.


Assuntos
Carpas , Doença Hepática Induzida por Substâncias e Drogas , Ácido Tióctico , Animais , Humanos , Carpas/metabolismo , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Ácido Tióctico/farmacologia , Carpa Dourada/metabolismo , Amônia/toxicidade , Amônia/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Inflamação
2.
Chemosphere ; 332: 138892, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37169085

RESUMO

This study investigated the effectiveness and mechanism for the control of internal phosphorus (P) liberation from sediment by hydrous zirconium oxide (HZrO2) combined with calcite, bentonite and zeolite. The results suggested that coexisting calcite, calcium-modified bentonite (CaBT) and calcium-modified zeolite (CaZ) all had the ability to promote the adsorption of phosphate (PO43-) onto HZrO2. The mechanisms of PO43- elimination by HZrO2/calcite mixture involved the adsorption of PO43- on calcite, the precipitation of PO43- with Ca2+, and the inner-sphere complexation of PO43- with HZrO2. The amendment of sediment with HZrO2/calcite, HZrO2/CaBT or HZrO2/CaZ mixture can effectively prevent the sedimentary P release, and the immobilization of mobile P in the sediment and the uptake of dissolved reactive P (DRP) from the interstitial water by the amendment material played a key role in the control of P release from sediment by the combined amendment. Capping sediment with HZrO2/calcite, HZrO2/CaBT or HZrO2/CaZ mixture also can effectively intercept sediment P release, and the formation of P static layer attributed to the uptake of interstitial water DRP and DGT (diffusive gradient in thin-films)-unstable P in the upper sediment by the capping material was a key to the inhibition of sedimentary P migration into the overlying water by the combined capping. The great majority of P immobilized by the HZrO2/calcite, HZrO2/CaBT or HZrO2/CaZ combined covering layer is stable P and it has a low re-releasing risk under dissolved oxygen-deficit and pH 5-9 condition. The stability of P bound by the combined covering layer was larger than that by the single HZrO2 covering layer. The results of this research show that the combined use of HZrO2 and calcite, HZrO2 and CaBT, or HZrO2 and CaZ as a capping material has great potential in the reduction of sediment P loading.


Assuntos
Poluentes Químicos da Água , Zeolitas , Carbonato de Cálcio , Poluentes Químicos da Água/análise , Fósforo , Bentonita , Cálcio , Sedimentos Geológicos
3.
bioRxiv ; 2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-36993242

RESUMO

Phase transitions of cellular proteins and lipids play a key role in governing the organisation and coordination of intracellular biology. The frequent juxtaposition of proteinaceous biomolecular condensates to cellular membranes raises the intriguing prospect that phase transitions in proteins and lipids could be co-regulated. Here we investigate this possibility in the ribonucleoprotein (RNP) granule-ANXA11-lysosome ensemble, where ANXA11 tethers RNP granule condensates to lysosomal membranes to enable their co-trafficking. We show that changes to the protein phase state within this system, driven by the low complexity ANXA11 N-terminus, induce a coupled phase state change in the lipids of the underlying membrane. We identify the ANXA11 interacting proteins ALG2 and CALC as potent regulators of ANXA11-based phase coupling and demonstrate their influence on the nanomechanical properties of the ANXA11-lysosome ensemble and its capacity to engage RNP granules. The phenomenon of protein-lipid phase coupling we observe within this system offers an important template to understand the numerous other examples across the cell whereby biomolecular condensates closely juxtapose cell membranes.

4.
Org Biomol Chem ; 20(43): 8415-8419, 2022 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-36278798

RESUMO

A formal [4 + 2] annulation of diamines and prop-2-ynyl sulfonium salts was developed. This strategy enables efficient access to tetrahydroquinoxalines in excellent yields.


Assuntos
Diaminas , Sais
5.
HERD ; 15(4): 369-390, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35927925

RESUMO

BACKGROUND: The pediatric intensive care unit (PICU) is an environment where seriously ill children receive complex care, delivered mostly by specialty-trained nurses (registered nurses [RNs]) who must perform multiple high-level tasks. With stressors on healthcare systems at an all-time high, design that optimizes RN workflow has taken on a renewed imperative. OBJECTIVES: To employ a multimodal approach (1) to identify environmental factors in the PICU patient room that contribute to caregiver workflow inefficiencies, (2) to optimize safety by identifying high-touch surfaces that cause hospital-acquired infections, (3) to develop human-centered design recommendations. METHODS: This mixed-method case study was conducted in a 23-bed urban hospital PICU. The activities, movements, and workflows of 13 RNs were recorded using spatial movement mapping, behavioral mapping, and clinical activity mapping. Frequency of RN contact with surfaces was documented to assess relative infection transmission risk. Face-to-face interviews were conducted with RNs to elicit their views on care delivery and their physical work environment. RESULTS: Direct patient care occupied 50% of RNs' time. Of the direct patient care workflow activities recorded, 26% were to prepare for care around the bedside, while 27% were for random travel between clean and soiled areas. The surfaces most frequently touched were (1) patient bedrails, (2) intravenous pumps and poles, (3) tubing and medical equipment, and (4) vital sign monitors. CONCLUSION: Value-added tasks account for only about 20% of nurses' work. Combining technology and strategic interior design to streamline workflow and enhance infection prevention optimizes efficiency and empowers frontline providers to maximize their time at the bedside performing value-added tasks.


Assuntos
Unidades de Terapia Intensiva Pediátrica , Quartos de Pacientes , Atitude do Pessoal de Saúde , Criança , Humanos , Fluxo de Trabalho , Local de Trabalho
6.
J Manuf Syst ; 60: 837-851, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33649693

RESUMO

In the wake of COVID-19, the production demand of medical equipment is increasing rapidly. This type of products is mainly assembled by hand or fixed program with complex and flexible structure. However, the low efficiency and adaptability in current assembly mode are unable to meet the assembly requirements. So in this paper, a new framework of human-robot collaborative (HRC) assembly based on digital twin (DT) is proposed. The data management system of proposed framework integrates all kinds of data from digital twin spaces. In order to obtain the HRC strategy and action sequence in dynamic environment, the double deep deterministic policy gradient (D-DDPG) is applied as optimization model in DT. During assembly, the performance model is adopted to evaluate the quality of resilience assembly. The proposed framework is finally validated by an alternator assembly case, which proves that DT-based HRC assembly has a significant effect on improving assembly efficiency and safety.

7.
Bioresour Technol ; 254: 347-352, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29395740

RESUMO

Good start-up and performance are essential for the completely autotrophic nitrogen removal over nitrite (CANON) process, and inorganic carbon (IC) is also important for this process. In this study, a lab-scale submerged aerated biological filter (SABF) was adopted for the CANON process. A 16S rRNA gene high-throughput sequencing analysis showed that the phyla Proteobacteria and Planctomycetes were the dominant microorganisms and that the genus Candidatus Brocadia functioned as the nitrogen remover. The effect of IC on the nitrogen removal was analyzed. The results showed that the optimum concentration ratio of IC to nitrogen (IC/N) was 1.2, which produced the highest average ammonium nitrogen removal rate (ANR) and total nitrogen removal rate (TNR) values of 95.5% and 80.3%, respectively. The average AOB and AnAOB activities were 2.45 mg·L-1·h-1 and 3.57 mg·L-1·h-1, respectively. This research could promote the nitrogen removal ability of the CANON process with a SABF in the future.


Assuntos
Reatores Biológicos , Desnitrificação , Processos Autotróficos , Carbono , Nitritos , Nitrogênio , RNA Ribossômico 16S
8.
Bioresour Technol ; 254: 67-74, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29413940

RESUMO

Dissolved oxygen (DO) is a crucial parameter of the completely autotrophic nitrogen removal over nitrite (CANON) process. This study determined the nitrogen removal performance and microbial community of the CANON process in a laboratory-scale submerged aerated biological filter (SABF) over a DO concentration range from 0 to 1.2 mg·L-1. The results showed that the optimum DO (0.2-0.3 mg·L-1) corresponded to an average ammonium nitrogen removal efficiency of 93.4% and a total nitrogen removal efficiency of 81.0%. A 16S rRNA gene high-throughput sequencing technology confirmed that the phyla Proteobacteria and Nitrospirae enriched, whereas the phylum Planctomycetes was inhibited with increasing DO concentration. At the genus level, the increase of DO concentration resulted in the enrichment of genera Dok59 and Nitrospira, but restrained the genus Candidatus Brocadia. This research can be used to improve the nitrogen removal ability of the CANON process in an SABF in the future.


Assuntos
Desnitrificação , Nitritos , Nitrogênio , Processos Autotróficos , Reatores Biológicos , Oxigênio , RNA Ribossômico 16S
9.
Rev Econ Househ ; 16(1): 5-19, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30930702

RESUMO

We consider returns to scale in food preparation as a potential resolution of a puzzle raised by Deaton and Paxson (Journal of Political Economy, 106(5), 897-930, 1998). We clarify the conditions under which returns to scale in food preparation can resolve the puzzle. The key requirement is that foods are heterogeneous in time costs. We then show that detailed food expenditure and time use data are consistent with larger households shifting to more time intensive foods.

10.
Health Rep ; 25(4): 13-7, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24744043

RESUMO

BACKGROUND: Canadian households are spending an increasing share of their household income on health care not covered by public plans. This study investigates trends in out-of-pocket expenditures for health care services and products by household income quintile from 1997 to 2009. DATA AND METHODS: Biennial estimates from the Survey of Household Spending between 1997 and 2009 were used to examine changes in out-of-pocket health care expenditures, by household income quintile. The statistical significance of these changes was assessed using linear and logistic regression. RESULTS: In 2009, the percentage of after-tax household income spent on health care among low-income households (5.7%) was nearly twice that of high-income households (2.6%). Approximately 40% of households in the two lowest income quintiles spent more than 5% of their total after-tax income on health care services and products, compared with 14% of households in the highest income quintile. The increase in spending between 1997 and 2009 was greatest for households in the lowest income quintile (63%). INTERPRETATION: Out-of-pocket health care expenditures have increased for households in all income quintiles, but the relative increase was greatest among households in lower income quintiles.


Assuntos
Financiamento Pessoal/estatística & dados numéricos , Gastos em Saúde/estatística & dados numéricos , Renda/estatística & dados numéricos , Canadá , Assistência Odontológica/economia , Custos de Medicamentos/estatística & dados numéricos , Características da Família , Humanos , Seguro/economia , Seguro/estatística & dados numéricos , Seguro Saúde/economia , Seguro Saúde/estatística & dados numéricos , Pobreza/estatística & dados numéricos , Medicamentos sob Prescrição/economia
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