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1.
Bioresour Technol ; 326: 124728, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33508642

RESUMO

In this work, a laboratory-scale alternating anaerobic/aerobic biofilter (A/O BF) filled with self-made steel slag media was constructed, where the integrated biological and crystalline phosphorus removal process was realized to remove phosphorus and achieve phosphorus recovery from wastewater. Phosphorus accumulating organisms (PAOs) were successfully enriched within 30 days operation, the maximum phosphate removal efficiency was close to 80% under the optimal conditions with the anaerobic time of 34 h, HRT of 4 h and influent COD of 300 mg/L. The analysis of SEM-EDS and XRD indicated that hydroxyapatite (HAP) crystals were formed inside biofilms without addition of chemical reagents. The high phosphate environment created by PAOs and the release of Ca2+ from the steel slag media might be responsible for the generation of HAP. These findings have crucial implications for the application BF technology to remove and recover phosphorus from wastewater.


Assuntos
Fenômenos Biológicos , Eliminação de Resíduos Líquidos , Anaerobiose , Reatores Biológicos , Cristalização , Durapatita , Fósforo , Esgotos
2.
Sci Total Environ ; 758: 144157, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33333300

RESUMO

The increasing number of chemicals detected in the marine environment underlines the need for appropriate prioritization strategies prior to further testing and potential inclusion into monitoring programs. Here, a prioritization strategy is proposed for chemicals detected in the North Sea over the last decade, through the development of a Concern Index (CI) using exposure and toxicity data obtained from peer-review publications and the ToxCast database, respectively. A total of 158 chemicals were ranked and the most sensitive tested assay endpoints were identified. Additionally, similar analysis was performed for the classes of chemicals and Biological Process Targets (BPTs). By first ranking chemicals currently acknowledged for their high toxicity to the aquatic environment, i.e. naphthalene, salicylic acid and simazine, the obtained results not only reinforce the risk posed by these but also promote a confident extrapolation from mammalian in vitro toxicity data to fish. Furthermore, genes targeted by the most sensitive assays, related to basic cell maintenance processes and immune defense, are highly evolutionarily conserved across species. The identification of these assays further reinforces the importance of a shift from traditional toxicity endpoints to lower levels of biological organization, allowing the detection of adverse effects at lower concentrations.


Assuntos
Bioensaio , Fenômenos Biológicos , Animais , Bases de Dados Factuais , Mar do Norte
3.
Ned Tijdschr Tandheelkd ; 127(12): 727-733, 2020 Dec.
Artigo em Holandês | MEDLINE | ID: mdl-33367301

RESUMO

In general, the result of orthodontic treatment is not stable. After active treatment, changes can occur as a result of a number of biological processes. The application of retention aims to counteract such changes and thereby preserve the result of orthodontic treatment. The way practitioners design the retention phase varies considerably. To reduce undesired variation in orthodontic retention between practices and to improve quality of care, clinical practice guidelines for retention were developed by the Dutch Association of Orthodontists. These guidelines contain recommendations for the application of retention. The duration of retention, additional techniques and retention after treatment of Class II malocclusions are discussed; consensus has not yet been reached on these subjects.


Assuntos
Fenômenos Biológicos , Padrões de Prática Odontológica , Assistência Odontológica , Humanos , Desenho de Aparelho Ortodôntico , Ortodontistas
5.
Nat Commun ; 11(1): 6348, 2020 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-33311506

RESUMO

Long non-coding RNAs are important regulators of biological processes including immune responses. The immunoregulatory functions of lncRNAs have been revealed primarily in murine models with limited understanding of lncRNAs in human immune responses. Here, we identify lncRNA LUCAT1 which is upregulated in human myeloid cells stimulated with lipopolysaccharide and other innate immune stimuli. Targeted deletion of LUCAT1 in myeloid cells increases expression of type I interferon stimulated genes in response to LPS. By contrast, increased LUCAT1 expression results in a reduction of the inducible ISG response. In activated cells, LUCAT1 is enriched in the nucleus where it associates with chromatin. Further, LUCAT1 limits transcription of interferon stimulated genes by interacting with STAT1 in the nucleus. Together, our study highlights the role of the lncRNA LUCAT1 as a post-induction feedback regulator which functions to restrain the immune response in human cells.


Assuntos
Regulação da Expressão Gênica , Interferons/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Animais , Fenômenos Biológicos , Cromatina/metabolismo , Citocinas/metabolismo , Retroalimentação , Técnicas de Silenciamento de Genes , Humanos , Imunidade Inata/efeitos dos fármacos , Lipopolissacarídeos/efeitos adversos , Camundongos , Células Mieloides/metabolismo , Proteínas , Fator de Transcrição STAT1/metabolismo , Células THP-1
8.
Bioresour Technol ; 318: 124200, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33035946

RESUMO

Suspended growth biological process (SGBP) with post-ozonation (O3) was investigated for treatment of simulated complex mixed industrial and domestic wastewater at specific conditions. The SGBP was operated under complete aeration, 30/30-min and 60/30-min on/off aeration cycles and effluent was exposed to ozone at 250 mgO3/h fixed dose and contact time 1 to 60-min. The SGBP performance was maximum under 60/30-min aeration conditions achieving 92.1, 90.6, 83.3 and 83.8% reduction in COD, BOD5, TN and PO4-P respectively. Nitrification (64.1%) was uninhibited even on transition to pulse aeration cycles. The concentrations of diesel oil and methylene blue dye were reduced by 83.6 and 93.5% respectively. Post-ozonation oxidized residual organics up to 19.9%, based on COD measurement, and increased effluent BOD5 up to 49.5%. The results including the crop growth outcomes indicate that SGBP-O3 process has great potential to improve the quality of mixed industrial and domestic wastewater considerably for various water reuse applications.


Assuntos
Fenômenos Biológicos , Ozônio , Purificação da Água , Agricultura , Eliminação de Resíduos Líquidos , Águas Residuárias
9.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 2235-2238, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018452

RESUMO

Electroporation is a well-established technique used to stimulate cells, enhancing membrane permeability. Although the biological phenomena occurring after the poration process have been widely studied, the physical mechanisms of pore formation are not clearly understood. In this work we investigated by means of molecular dynamics simulations the kinetics of pore formation, linking the different stages of poration to specific arrangements of lipid membrane domains.Clinical Relevance-The approach followed in this study aims to shed light on the molecular mechanisms at the basis of the electroporation technique, nowadays used to enhance the entrance of poorly permeant anticancer drugs into tumor cells, for gene electrotransfer and all the other applications exploiting the modulation of cell membrane properties.


Assuntos
Fenômenos Biológicos , Bicamadas Lipídicas , Eletroporação , Cinética , Simulação de Dinâmica Molecular
12.
PLoS One ; 15(9): e0238998, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32941473

RESUMO

The frequent contact people have with liquids containing pathogenic microorganisms provides opportunities for disease transmission. In this work, we quantified the transfer of bacteria-using E. coli as a model- from liquid to skin, estimated liquid retention on the skin after different contact activities (hand immersion, wet-cloth and wet-surface contact), and estimated liquid transfer following hand-to-mouth contacts. The results of our study show that the number of E. coli transferred to the skin per surface area (n [E. coli/cm2]) can be modeled using n = C (10-3.38+h), where C [E. coli/cm3] is the concentration of E. coli in the liquid, and h [cm] is the film thickness of the liquid retained on the skin. Findings from the E. coli transfer experiments reveal a significant difference between the transfer of E. coli from liquid to the skin and the previously reported transfer of viruses to the skin. Additionally, our results demonstrate that the time elapsed since the interaction significantly influences liquid retention, therefore modulating the risks associated with human interaction with contaminated liquids. The findings enhance our understanding of liquid-mediated disease transmission processes and provide quantitative estimates as inputs for microbial risk assessments.


Assuntos
Adsorção/fisiologia , Dermatopatias Bacterianas/transmissão , Pele/microbiologia , Fenômenos Biológicos , Transmissão de Doença Infecciosa/prevenção & controle , Escherichia coli/patogenicidade , Mãos , Humanos , Modelos Teóricos , Água/química , Microbiologia da Água
13.
PLoS One ; 15(9): e0239044, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32931501

RESUMO

Holothuria leucospilota (Echinodermata: Holothuroidea) is a widespread tropical sea cucumber with strong value for the ecological restoration of coral reefs. Therefore, some studies regarding the artificial breeding and cultivation of H. leucospilota have been undertaken recently. However, the biological functions of the digestive system of this species have not been elucidated. In this study, a cDNA coding for α-amylase, an indicator of digestive maturity in animals, was identified from H. leucospilota and designated Hl-Amy. The full-length cDNA of the Hl-Amy gene, which is 1734 bp in length with an open reading frame (ORF) of 1578 bp, encodes a 525 amino acid (a.a.) protein with a deduced molecular weight of 59.34 kDa. According to the CaZy database annotation, Hl-Amy belongs to the class of GH-H with the official nomenclature of α-amylase (EC 3.2.1.1) or 4-α-D-glucan glucanohydrolase. The Hl-Amy protein contains a signal peptide at the N-terminal followed by a functional amylase domain, which includes the catalytic activity site. The mRNA expression of Hl-Amy was abundantly exhibited in the intestine, followed by the transverse vessel with a low level, but was hardly detected in other selected tissues. During embryonic and larval development, Hl-Amy was constitutively expressed in all stages, and the highest expression level was observed in the blastula. By in situ hybridization (ISH), positive Hl-Amy signals were observed in different parts of the three different intestinal segments (foregut, midgut and hindgut). The Hl-Amy recombinant protein was generated in an E. coli system with codon optimization, which is necessary for Hl-Amy successfully expressed in this heterogenous system. The Hl-Amy recombinant protein was purified by immobilized metal ion affinity chromatography (IMAC), and its activity of starch hydrolysis was further detected. The optimal temperatures and pH for Hl-Amy recombinant protein were 55°C and 6.0, respectively, with an activity of 62.2 U/mg. In summary, this current study has filled a knowledge gap on the biological function and expression profiles of an essential digestive enzyme in sea cucumber, which may encourage future investigation toward rationalized diets for H. leucospilota in artificial cultivation, and optimized heterogenous prokaryotic systems for producing recombinant enzymes of marine origins.


Assuntos
Pepinos-do-Mar/enzimologia , Pepinos-do-Mar/genética , alfa-Amilases/genética , Sequência de Aminoácidos/genética , Animais , Fenômenos Biológicos , Clonagem Molecular/métodos , Códon/genética , DNA Complementar/genética , Equinodermos/genética , Perfilação da Expressão Gênica/métodos , Fases de Leitura Aberta/genética , Filogenia , Alinhamento de Sequência/métodos , Distribuição Tecidual/genética , alfa-Amilases/metabolismo
14.
Nat Commun ; 11(1): 4334, 2020 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-32859911

RESUMO

The metabolome includes not just known but also unknown metabolites; however, metabolite annotation remains the bottleneck in untargeted metabolomics. Ion mobility - mass spectrometry (IM-MS) has emerged as a promising technology by providing multi-dimensional characterizations of metabolites. Here, we curate an ion mobility CCS atlas, namely AllCCS, and develop an integrated strategy for metabolite annotation using known or unknown chemical structures. The AllCCS atlas covers vast chemical structures with >5000 experimental CCS records and ~12 million calculated CCS values for >1.6 million small molecules. We demonstrate the high accuracy and wide applicability of AllCCS with medium relative errors of 0.5-2% for a broad spectrum of small molecules. AllCCS combined with in silico MS/MS spectra facilitates multi-dimensional match and substantially improves the accuracy and coverage of both known and unknown metabolite annotation from biological samples. Together, AllCCS is a versatile resource that enables confident metabolite annotation, revealing comprehensive chemical and metabolic insights towards biological processes.


Assuntos
Espectrometria de Mobilidade Iônica/métodos , Metaboloma/fisiologia , Metabolômica/métodos , Algoritmos , Fenômenos Biológicos , Confiabilidade dos Dados , Bases de Dados Factuais , Redes e Vias Metabólicas , Software , Espectrometria de Massas em Tandem
15.
Proc Natl Acad Sci U S A ; 117(35): 21804-21812, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32817546

RESUMO

Several recent studies have shown that the concept of proteome constraint, i.e., the need for the cell to balance allocation of its proteome between different cellular processes, is essential for ensuring proper cell function. However, there have been no attempts to elucidate how cells' maximum capacity to grow depends on protein availability for different cellular processes. To experimentally address this, we cultivated Saccharomyces cerevisiae in bioreactors with or without amino acid supplementation and performed quantitative proteomics to analyze global changes in proteome allocation, during both anaerobic and aerobic growth on glucose. Analysis of the proteomic data implies that proteome mass is mainly reallocated from amino acid biosynthetic processes into translation, which enables an increased growth rate during supplementation. Similar findings were obtained from both aerobic and anaerobic cultivations. Our findings show that cells can increase their growth rate through increasing its proteome allocation toward the protein translational machinery.


Assuntos
Regulação Fúngica da Expressão Gênica/genética , Biossíntese de Proteínas/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/metabolismo , Aminoácidos/biossíntese , Aminoácidos/metabolismo , Fenômenos Bioquímicos , Fenômenos Biológicos , Perfilação da Expressão Gênica/métodos , Regulação Fúngica da Expressão Gênica/fisiologia , Glucose/metabolismo , Proteoma/metabolismo , Proteômica , Ribossomos/metabolismo , Ribossomos/fisiologia , Proteínas de Saccharomyces cerevisiae/metabolismo
17.
Acta Crystallogr C Struct Chem ; 76(Pt 7): 673-680, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32624514

RESUMO

Four new picolinohydrazonamide derivatives, namely, 6-methyl-N'-(morpholine-4-carbonothioyl)picolinohydrazonamide, C12H17N5OS, 6-chloro-N'-(morpholine-4-carbonothioyl)picolinohydrazonamide methanol monosolvate, C11H14ClN5OS·CH3OH, 6-chloro-N'-(4-phenylpiperazine-1-carbonothioyl)picolinohydrazonamide, C17H19ClN6S, and 6-chloropicolinohydrazonamide, C6H7ClN4, have been synthesized and characterized by NMR spectroscopy and single-crystal low-temperature X-ray diffraction. In addition, their antibacterial and anti-yeast activities have been determined. The first three compounds adopt the zwitterionic form in the crystal structure regardless of the presence or absence of solvent molecules in the structure. They also adopt the same symmetry, i.e. P21/c (P21/n), unlike the fourth structure which is chiral and has the space group P212121. For all the studied cases, intermolecular N-H...O and N-H...N hydrogen bonds play an essential role in the formation of the structures.


Assuntos
Antibacterianos/farmacologia , Morfolinas/química , Antibacterianos/química , Fenômenos Biológicos , Cristalografia por Raios X , Ligação de Hidrogênio , Estrutura Molecular , Solventes/química
18.
PLoS One ; 15(7): e0234648, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32645027

RESUMO

Adaptation of weeds to water stress could result in the broader distribution, and make weed control task increasingly difficult. Therefore, a clear understanding of the biology of weeds under water stress could assist in the development of sustainable weed management strategies. Avena fatua (wild oat) and A. ludoviciana (sterile oat) are problematic weeds in Australian winter crops. The objectives of this study were to determine the growth and reproductive behaviour of A. fatua and A. ludoviciana at different soil moisture levels [20, 40, 60, 80, and 100% water holding capacity (WHC)]. Results revealed that A. fatua did not survive and failed to produce seeds at 20 and 40% WHC. However, A. ludoviciana survived at 40% WHC and produced 54 seeds plant-1. A. fatua produced a higher number of seeds per plant than A. ludoviciana at 80 (474 vs 406 seeds plant-1) and 100% WHC (480 vs 417 seeds plant-1). Seed production for both species remained similar at 80 and 100% WHC; however, higher than 60% WHC. Seed production of A. fatua and A. ludoviciana was 235 and 282 seeds plant-1, respectively, at 60% WHC. The 60% WHC reduced seed production of A. fatua and A. ludoviciana by 51 and 32% respectively, compared to 100% WHC. The plant height, leaf weight, stem weight, and root weight per plant of A. fatua at 60% WHC reduced by 45, 27, 32, and 59%, respectively, as compared with 100% WHC. Similarly, the plant height, leaf weight, stem weight, and root weight per plant of A. ludoviciana at 60% WHC reduced by 45, 35, 47 and 76%, respectively, as compared with 100% WHC. Results indicate that A. ludoviciana can survive and produce seeds at 40% of WHC, indicating the adaptation of the species to dryland conditions. The results also suggest that A. ludoviciana is likely to be robust under water stress conditions, potentially reducing crop yield. The ability of A. fatua and A. ludoviciana to produce seeds under water-stressed conditions (60% WHC) necessitates integrated weed management strategies that suppress these weeds whilst taking into account the efficient utilization of stored moisture for winter crops.


Assuntos
Avena/crescimento & desenvolvimento , Solo/química , Controle de Plantas Daninhas/métodos , Austrália , Fenômenos Biológicos , Produtos Agrícolas/crescimento & desenvolvimento , Desidratação/metabolismo , Folhas de Planta/crescimento & desenvolvimento , Plantas Daninhas/crescimento & desenvolvimento , Água/metabolismo
20.
Proc Natl Acad Sci U S A ; 117(27): 15748-15754, 2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-32571943

RESUMO

Trade-offs between growth, reproduction, and lifespan constrain animal life histories, leading to evolutionary diversification of life history cycles in different environments. In female mammals, gestation and lactation are expected to impose the major costs of reproduction, driving reproductive trade-offs, although mating also requires interactions with males that could themselves influence life history. Here we show that a male's presence by itself leads to lifelong alterations in life history in female mice. Housing C57BL/6J female mice with sterilized males early in life led to an increase in body weight, an effect that persisted across life even when females were later allowed to produce pups. We found that those females previously housed with sterile males also showed enhanced late-life offspring production when allowed to reproduce, indicating that earlier mating can influence subsequent fecundity. This effect was the opposite to that seen in females previously housed with intact males, which showed the expected trade-off between early-life and late-life reproduction. However, housing with a sterile male early in life came at a cost to lifespan, which was observed in the absence of females ever undergoing fertilization. Endocrinologically, mating also permanently reduced the concentration of circulating prolactin, a pituitary hormone influencing maternal care. Changes in hormone axes that influence reproduction could therefore help alter life history allocation in response to opposite-sex stimuli. Our results demonstrate that mating itself can increase growth and subsequent fecundity in mammals, and that responses to sexual stimuli could account for some lifespan trade-offs normally attributed to pregnancy and lactation.


Assuntos
Evolução Biológica , Fertilidade/fisiologia , Longevidade/fisiologia , Reprodução/fisiologia , Animais , Fenômenos Biológicos , Peso Corporal/genética , Peso Corporal/fisiologia , Comunicação Celular , Feminino , Fertilidade/genética , Infertilidade Masculina/genética , Lactação , Longevidade/genética , Masculino , Camundongos , Reprodução/genética , Comportamento Sexual Animal/fisiologia
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