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1.
Sci Rep ; 14(1): 24550, 2024 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-39426994

RESUMO

It never rains in standard lab-confinements; thus we have limited understanding of animal reactions to water and wetness. To address this issue, we sprayed water on different body parts of rats and measured drying and fur temperature by thermal imaging while manipulating behavior, sensory cues and fur. Spraying water on rats resulted in fur changes (hair clumping, apex formation), grooming, shaking, and scratching. Anesthesia abolished behavioral responses, interfered with fur changes, and slowed drying. Spraying water on different body parts resulted in differential behavioral drying responses. Spraying the head resulted in grooming and shaking responses; water evaporated from the head twice as fast as water sprayed on the animal's back or belly. We observed no effect of whisker removal on post-water-spraying behavior. In contrast, local anesthesia of dorsal facial skin reduced post-water-spraying behavioral responses. Shaving of head fur drastically enhanced post-water-spraying behaviors, but reduced water loss during drying; indicating that fur promotes evaporation, acting in tandem with behavior to mediate drying. Excised wet fur patches dried and cooled faster than shaved excised wet skin. Water was sucked into distal hair tips, where it evaporated. We propose the wet-fur-heat-pump-hypothesis; fur might extract heat required for drying by cooling ambient air.


Assuntos
Comportamento Animal , Sinais (Psicologia) , Animais , Ratos , Comportamento Animal/fisiologia , Masculino , Água , Pelo Animal , Asseio Animal/fisiologia , Dessecação/métodos , Ratos Sprague-Dawley , Molhabilidade
2.
Cell Rep ; 43(9): 114665, 2024 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-39215998

RESUMO

The neural basis of tongue mechanosensation remains largely mysterious despite the tongue's high tactile acuity, sensitivity, and relevance to ethologically important functions. We studied terminal morphologies and tactile responses of lingual afferents from the trigeminal ganglion. Fungiform papillae, the taste-bud-holding structures in the tongue, were convergently innervated by multiple Piezo2+ trigeminal afferents, whereas single trigeminal afferents branched into multiple adjacent filiform papillae. In vivo single-unit recordings from the trigeminal ganglion revealed lingual low-threshold mechanoreceptors (LTMRs) with distinct tactile properties ranging from intermediately adapting (IA) to rapidly adapting (RA). The receptive fields of these LTMRs were mostly less than 0.1 mm2 and concentrated at the tip of the tongue, resembling the distribution of fungiform papillae. Our results indicate that fungiform papillae are mechanosensory structures and suggest a simple model that links functional and anatomical properties of tactile sensory neurons in the tongue.


Assuntos
Mecanorreceptores , Língua , Gânglio Trigeminal , Animais , Língua/inervação , Língua/fisiologia , Camundongos , Gânglio Trigeminal/fisiologia , Mecanorreceptores/fisiologia , Mecanorreceptores/metabolismo , Tato/fisiologia , Camundongos Endogâmicos C57BL , Papilas Gustativas/fisiologia , Masculino
3.
Appl Opt ; 63(10): 2587-2593, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38568540

RESUMO

A novel approach, to the best of our knowledge, is presented for assessing silicon wafer surface profiles using an interferometer and vertically rotatable wafer holder. This approach significantly enhances precision and reduces costs, and outperforms traditional techniques in measurement consistency and accuracy. It effectively reduces sample distortion and positional shifts owing to the removal and reinstallation of the wafers. Using this method, a global backsurface-referenced ideal range of 0.385 µm, warp of 0.193 µm, and other parameters were obtained, demonstrating its practicality in efficiently capturing key surface profile metrics for silicon wafers. This innovation promises substantial improvements in high-volume wafer surface profile testing, overcoming prevalent technological challenges in this industry.

4.
Curr Biol ; 33(22): R1203-R1205, 2023 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-37989101

RESUMO

Muscular hydrostats, such as the elephant trunk, can perform precise motor actions. A new study has revealed that the elephant trunk contains a dense network of tiny muscle fascicles, suggesting that muscle miniaturization may be a key toward understanding how soft organs achieve both strength and dexterity.


Assuntos
Elefantes , Animais , Músculo Esquelético
5.
bioRxiv ; 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37745619

RESUMO

It never rains in standard lab-confinements; thus we have limited understanding of animal reactions to water and wetness. To address this issue, we sprayed water on different body parts of rats and measured drying and fur temperature by thermal imaging while manipulating behavior, sensory cues and fur. Spraying water on rats resulted in fur changes (hair clumping, apex formation), grooming, shaking, and scratching. Anesthesia abolished behavioral responses, interfered with fur changes, and slowed drying. Spraying water on different body parts resulted in differential behavioral drying responses. Spraying the head resulted in grooming and shaking responses; water evaporated twice as fast as water sprayed on the animal's back or belly. We observed no effect of whisker removal on post-water-spraying behavior. In contrast, local anesthesia of dorsal facial skin reduced post-water-spraying behavioral responses. Shaving of head fur drastically enhanced post-water-spraying behaviors, but reduced water loss during drying; indicating that fur promotes evaporation, acting in tandem with behavior to mediate drying. Excised wet fur patches dried and cooled faster than shaved excised wet skin. Water was sucked into distal hair tips, where it evaporated. We propose the wet-fur-heat-pump-hypothesis; fur might extract heat required for drying by cooling ambient air.

6.
bioRxiv ; 2023 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-37645855

RESUMO

The mammalian tongue is richly innervated with somatosensory, gustatory and motor fibers. These form the basis of many ethologically important functions such as eating, speaking and social grooming. Despite its high tactile acuity and sensitivity, the neural basis of tongue mechanosensation remains largely mysterious. Here we explored the organization of mechanosensory afferents in the tongue and found that each lingual papilla is innervated by Piezo2 + trigeminal neurons. Notably, each fungiform papilla contained highly specialized ring-like sensory neuron terminations that circumscribe the taste buds. Myelinated lingual afferents in the mouse lingual papillae did not form corpuscular sensory end organs but rather had only free nerve endings. In vivo single-unit recordings from the trigeminal ganglion revealed two types of lingual low-threshold mechanoreceptors (LTMRs) with conduction velocities in the Aδ range or above and distinct response properties: intermediately adapting (IA) units and rapidly adapting (RA) units. IA units were sensitive to static indentation and stroking, while RA units had a preference for tangential forces applied by stroking. Lingual LTMRs were not directly responsive to rapid cooling or chemicals that can induce astringent or numbing sensations. Genetic labeling of lingual afferents in the tongue revealed at least two types of nerve terminal patterns, involving dense innervation of individual fungiform papillae by multiple putatively distinct afferents, and relatively sparse innervation of filiform papillae. Together, our results indicate that fungiform papillae are mechanosensory structures, while suggesting a simple model that links the functional and anatomical properties of tactile sensory neurons in the tongue.

7.
Biotechnol Genet Eng Rev ; : 1-10, 2023 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-36966443

RESUMO

The selection of different examination sequences of painless gastroscopy in patients with difficult airway risk was explored in this study. A total of 45 patients undergoing painless gastroscopy with Mallampati airway score of III-IV were randomly assigned into two groups (A group and B group) according to the sequence of colonoscopy and gastroscopy. Group A was first examined by gastroscopy after anesthesia, and then by colonoscopy. Group B was examined in the opposite order, first by colonoscopy, and then by gastroscopy. Ramsay Sedation scores were evaluated every five minutes when gastroscopy was performed in the two groups. The dosage of propofol, blood pressure, heart rate, blood oxygen saturation, recovery time, hospital leaving time, and adverse reactions after induction and endoscopy were recorded. The dosage of propofol and change of vital signs in B group was less than that in A group. Operation time, recovery time, hospital leaving time and postoperative adverse reactions have no significant difference between two groups. For patients at risk of difficult airway, colonoscopy followed by gastroscopy has more stable intraoperative vital signs and less propofol consumption.

8.
J Org Chem ; 88(5): 2908-2920, 2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36799936

RESUMO

Enol esters and conjugated enynes are valuable structural motifs for synthetic chemistry and material sciences. Herein, the synthesis of tetra-substituted enol ester 2-iodobenzoate derivatives was achieved in good yields at room temperature through a gold-catalyzed acyloxyalkynylation of sensitive ynol ethers with ethynylbenziodoxolones (EBXs), the latter acting as bifunctional reactants. The conversion is highly regioselective with a broad substrate scope. Mechanistically, an Au(III) species is the key intermediate of an Au(I)/Au(III) redox cycle. The reaction is synthetically useful and can easily be scaled up to gram scale.

9.
Chemosphere ; 315: 137776, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36623593

RESUMO

Maternal exposure to regulated disinfection by-products (DBPs) during pregnancy has been linked with adverse birth outcomes. However, no human studies have focused on drinking water nitrosamines, a group of emerging unregulated nitrogenous DBPs that exhibits genotoxicity and developmental toxicity in experimental studies. This cohort study included 2457 mother-infant pairs from a single drinking water supply system in central China, and maternal trimester-specific and entire pregnancy exposure of drinking water nitrosamines were evaluated. Multivariable linear and Poisson regression models were used to estimate the associations between maternal exposure to nitrosamines in drinking water and birth outcomes [birth weight (BW), low birth weight (LBW), small for gestational age (SGA) and preterm delivery (PTD)]. Elevated maternal N-nitrosodimethylamine (NDMA) exposure in the second trimester and N-nitrosopiperidine (NPIP) exposure during the entire pregnancy were associated with decreased BW (e.g., ß = -88.6 g; 95% CI: -151.0, -26.1 for the highest vs. lowest tertile of NDMA; p for trend = 0.01) and increased risks of PTD [e.g., risk ratio (RR) = 2.16; 95% CI: 1.23, 3.79 for the highest vs. lowest tertile of NDMA; p for trend = 0.002]. Elevated maternal exposure of N-nitrosodiethylamine (NDEA) in the second trimester was associated with increased risk of SGA (RR = 1.80; 95% CI: 1.09, 2.98 for the highest vs. lowest tertile; p for trend = 0.01). Our study detected associations of maternal exposure to drinking water nitrosamines during pregnancy with decreased BW and increased risks of SGA and PTD. These findings are novel but require replication in other study populations.


Assuntos
Água Potável , Nitrosaminas , Nascimento Prematuro , Feminino , Humanos , Recém-Nascido , Gravidez , Peso ao Nascer , Estudos de Coortes , Dimetilnitrosamina/análise , Água Potável/análise , Retardo do Crescimento Fetal , Exposição Materna/efeitos adversos , Nitrosaminas/análise , China
10.
Environ Sci Pollut Res Int ; 30(2): 2544-2554, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35932345

RESUMO

To treat high-salt urea wastewater by microbial hydrolysis, it is necessary to overcome the dual problems of incomplete removal of nitrogen (N) from mixed strains and inhibition of microbial activity by high salt (NaCl) concentrations. In this paper, the mechanism of NaCl tolerance of Halomonas sp. H36 was investigated. Using molecular biology and enzymatic methods, it was proven that the strain's N-removal enzymes (urease; ammonia monooxygenase, AMO; nitrite reductase, NIR; nitrate reductase, NAR) played a key role in the removal of N, and the N-removal pathway was clarified. For the strain used to treat simulated ship domestic sewage, the urea nitrogen (CO(NH2)2-N)-removal rate was 88.52%, the ammonia nitrogen (NH4+-N)-removal rate was 91.16%, the total nitrogen (TN)-removal rate was 90.25%, and nitrite nitrogen (NO2--N) and nitrate nitrogen (NO3--N) did not accumulate. It was proven for the first time that Halomonas sp. H36 has the function of simultaneous urea hydrolysis-nitrification-denitrification with urea as the initial substrate and can simultaneously remove urea nitrogen and inorganic nitrogen from high-salt urea wastewater.


Assuntos
Halomonas , Águas Residuárias , Desnitrificação , Nitrogênio/metabolismo , Cloreto de Sódio/metabolismo , Salinidade , Processos Heterotróficos , Nitrificação , Reatores Biológicos
11.
Int J Mol Sci ; 23(19)2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36232768

RESUMO

Antibiotics are broadly restricted in modern husbandry farming, necessitating the need for efficient and low-cost immunomodulatory preparations in antibiotic-free and healthful farming. As is known to all, CpG oligonucleotides (CpG-ODNs, an effective innate immunostimulatory agent) recognized by TLR9 in mammals (while TLR21 in avians) could collaborate with some united agent to induce stronger immune responses, but the cost is prohibitively expensive for farmers. Here, considering the coordination between TLR2 and TLR9/TLR21, we firstly proposed the idea that the well-fermented Lactococcus lactis could be utilized as a CpG-plasmid carrier (LACpG10) to enhance the host's innate immunity against pathogenic invasion. In the present study, after obtaining LACpG10-HL from homogenized and lyophilized recombinant strain LACpG10, we treated primary chicken lymphocytes, two cell lines (HD11 and IPEC-J2), and chickens with LACpG10-HL, CpG plasmids (pNZ8148-CpG10), and other stimulants, and respectively confirmed the effects by conducting qRT-PCR, bacterial infection assays, and a zoological experiment. Our data showed that LACpG10-HL could induce excellent innate immunity by regulating autophagy reactions, cytokine expression, and motivating PRRs. Interestingly, despite having no direct antiseptic effect, LACpG10-HL improved the antibacterial capacities of lymphocytes and enterocytes at the first line of defense. Most importantly, water-supplied LACpG10-HL treatment reduced the average adverse event rates, demonstrating that LACpG10-HL maintained its excellent immunostimulatory and protective properties under farming conditions. Our research not only contributes to revealing the satisfactory effects of LACpG10-HL but also sheds new light on a cost-effective solution with optimal immune effects in green, antibiotic-free, and healthful husbandry farming.


Assuntos
Anti-Infecciosos Locais , Receptor Toll-Like 9 , Adjuvantes Imunológicos/farmacologia , Animais , Antibacterianos/farmacologia , Anti-Infecciosos Locais/farmacologia , Galinhas/metabolismo , Citocinas/farmacologia , Imunidade Inata , Mamíferos/metabolismo , Oligodesoxirribonucleotídeos/farmacologia , Receptor 2 Toll-Like , Receptor Toll-Like 9/metabolismo , Água/farmacologia
12.
Chem Commun (Camb) ; 58(79): 11095-11098, 2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-36098177

RESUMO

This work demonstrates for the first time that a photochromic metal organic framework (pMOF) can be employed as a promising class of NIR-II photothermal material based on the photoinduced donor-acceptor intermolecular charge transfer process. After further surface-modification, such UV-activated pMOF-a nanoparticles allow the strong inhibition of 4T1 cancer cells under 1064 nm laser irradiation.


Assuntos
Hipertermia Induzida , Estruturas Metalorgânicas , Nanopartículas , Neoplasias , Humanos , Estruturas Metalorgânicas/farmacologia , Neoplasias/terapia , Fototerapia , Nanomedicina Teranóstica
13.
Front Pediatr ; 10: 799284, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35252057

RESUMO

BACKGROUND: The aim of this study was to explore the source and morphology of a small supernumerary marker chromosome (sSMC) from karyotype analysis of a patient with a unique case of mosaic Turner syndrome. The study findings will provide technical reference and genetic counseling for similar cases. CASE PRESENTATION: A female patient with 46,X,+mar karyotype was diagnosed by genetic karyotype analysis. Genetic methods including fluorescence in situ hybridization (FISH) and copy number variation sequencing (CNV-seq) based on low-depth whole-genome sequencing were used to explore the source and morphology of sSMC. FISH technology showed that 56.5% of the cells were X and 43.5% of the cells were XY. CNV-seq detection found that the sSMC was chrY, implying that the patient's karyotype was mos 45,X[58.6%]/46,XY[41.4%]. Retrospective karyotype analysis indicated that the female patient's sSMC was inherited from her father's small chrY. Customized FISH probe of Yq12 microdeletion was positive, indicating that the sSMC was a del(Y)(q12). Based on the results of genetic diagnosis, the specialist doctor gave a comprehensive genetic consultation and ordered regular follow-up examinations. CONCLUSIONS: The findings of the current study showed that the chromosome description of the unique Turner case was mos 45,X[56.5%]/46,X,del(Y)(q12)[43.5%]. FISH technology played a key role in diagnosis of mosaicism. The terminal deletion of mosaic chrY provided a scientific and an accurate explanation for masculinity failure and abnormal sexual development of the current case.

14.
Nature ; 603(7901): 464-469, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35264793

RESUMO

The brain generates complex sequences of movements that can be flexibly configured based on behavioural context or real-time sensory feedback1, but how this occurs is not fully understood. Here we developed a 'sequence licking' task in which mice directed their tongue to a target that moved through a series of locations. Mice could rapidly branch the sequence online based on tactile feedback. Closed-loop optogenetics and electrophysiology revealed that the tongue and jaw regions of the primary somatosensory (S1TJ) and motor (M1TJ) cortices2 encoded and controlled tongue kinematics at the level of individual licks. By contrast, the tongue 'premotor' (anterolateral motor) cortex3-10 encoded latent variables including intended lick angle, sequence identity and progress towards the reward that marked successful sequence execution. Movement-nonspecific sequence branching signals occurred in the anterolateral motor cortex and M1TJ. Our results reveal a set of key cortical areas for flexible and context-informed sequence generation.


Assuntos
Córtex Motor , Movimento , Animais , Camundongos , Córtex Motor/fisiologia , Movimento/fisiologia , Optogenética , Córtex Somatossensorial/fisiologia , Língua/fisiologia , Tato
15.
Int J Mol Sci ; 23(2)2022 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-35054790

RESUMO

Intestinal homeostasis is a dynamic balance involving the interaction between the host intestinal mucosa, immune barrier, intestinal microecology, nutrients, and metabolites. Once homeostasis is out of balance, it will increase the risk of intestinal diseases and is also closely associated with some systemic diseases. Probiotics (Escherichia coli Nissle 1917, Akkermansia muciniphila, Clostridium butyricum, lactic acid bacteria and Bifidobacterium spp.), maintaining the gut homeostasis through direct interaction with the intestine, can also exist as a specific agent to prevent, alleviate, or cure intestinal-related diseases. With genetic engineering technology advancing, probiotics can also show targeted therapeutic properties. The aims of this review are to summarize the roles of potential native and engineered probiotics in oncology, inflammatory bowel disease, and obesity, discussing the therapeutic applications of these probiotics.


Assuntos
Diabetes Mellitus/microbiologia , Enteropatias/microbiologia , Mucosa Intestinal/fisiologia , Obesidade/microbiologia , Probióticos/uso terapêutico , Akkermansia , Animais , Bifidobacterium , Clostridium butyricum , Diabetes Mellitus/terapia , Escherichia coli , Homeostase , Humanos , Doenças Inflamatórias Intestinais/microbiologia , Doenças Inflamatórias Intestinais/terapia , Enteropatias/terapia , Mucosa Intestinal/microbiologia , Lactobacillales , Obesidade/terapia
16.
Biomed Res Int ; 2021: 6673655, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34734085

RESUMO

Ovarian cancer is one of the leading causes of gynecological malignancy-related deaths. The underlying molecular development mechanism has however not been elucidated. In this study, we used bioinformatics to reveal critical molecular and biological processes associated with ovarian cancer. The microarray datasets of miRNA and mRNA expression profiles were downloaded from the Gene Expression Omnibus (GEO) database. Besides, we performed target prediction of the identified differentially expressed miRNAs. The overlapped differentially expressed genes (DEGs) were obtained combined with miRNA targets predicted and the DEGs identified from the mRNA dataset. The Cytoscape software was used to design a regulatory network of miRNA-gene. Moreover, the overlapped DEGs in the network were subjected to enrichment analysis to explore the associated biological processes. The molecular protein-protein interaction (PPI) network was used to identify the key genes among the DEGs of prognostic value for ovarian cancer, and the genes were evaluated via Kaplan-Meier curve analysis. A total of 186 overlapped DEGs were identified. Through miRNA-gene network analysis, we found that miR-195-5p, miR-424-5p, and miR-497-5p highly exhibited targeted association with overlapped DEGs. The three miRNAs are critical in the regulatory network and act as tumor suppressors. The overlapped DEGs were mainly associated with protein metabolism, histogenesis, and development of the reproductive system and ocular tissues. The PPI network identified 10 vital genes that promote tumor progression. Survival analysis found that CEP55 and CCNE1 may be associated with the prognosis of ovarian cancer. These findings provide insights to understand the pathogenesis of ovarian cancer and suggest new candidate biomarkers for early screening of ovarian cancer.


Assuntos
MicroRNAs/genética , Neoplasias Ovarianas/genética , RNA Mensageiro/genética , Biomarcadores Tumorais/genética , China , Biologia Computacional/métodos , Bases de Dados Genéticas , Feminino , Expressão Gênica/genética , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica/genética , Ontologia Genética , Redes Reguladoras de Genes/genética , Humanos , Estimativa de Kaplan-Meier , Análise em Microsséries , Prognóstico , Mapas de Interação de Proteínas/genética , Software , Análise de Sobrevida , Transcriptoma/genética
17.
Fish Shellfish Immunol ; 118: 72-84, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34474150

RESUMO

Misgurnus anguillicaudatus (M. anguillicaudatus) is a widely cultivated fish. However, in M. anguillicaudatus breeding, the frequent cold stress during daily breeding could induce immune suppression and increase the risk of infection, causing serious economic loss. Based on existing findings, CpG Oligonucleotides (CpG-ODNs) may be an ideal protective agent for low temperature fish breeding, performing anti-infective when faced with cold stress with cold shock proteins Y box binding proteins (YBX). Although YBX has pleiotropic functions, its roles in CpG-ODNs-mediated immunity (especially under cold situations) remain largely unexplored. To clarify the relationship among them, we identified the YBX1/YBX2 in M. anguillicaudatus and analyzed using a series of bioinformatics methods. After that, we immunized the fish with 3 types of CpG-ODNs and challenged with Aeromonas hydrophila (A. hydrophila). Here we showed that the best anti-bacterial effect of CpG-B was accompanied by the significant upregulation of YBX1. And the detection of the YBX1 downstream effectors confirmed that CpG-B induced the YBX1-mediated Th1 oriented responses to A. hydrophila by regulation of the NLRP3 (Caspase-A/-B), IL-1ß, IL-12 and IFN-γ. Afterwards, we found that under cold stress, CpG-B can activate the NLRP3 and NF-κB pathways through YBX1, a key mediator of anti-A. hydrophila in CpG-B immunization. In this study, we demonstrated CpG-B protection against infection in low temperature, and its interaction with YBX1, expanded the research of CpG-ODN under cold stress, and provided a new CpG-ODN application for low temperature fish farming.


Assuntos
Infecções Bacterianas , Cipriniformes , Adjuvantes Imunológicos , Animais , Resposta ao Choque Frio , Proteína 3 que Contém Domínio de Pirina da Família NLR , Oligodesoxirribonucleotídeos
18.
Appl Microbiol Biotechnol ; 105(14-15): 5973-5991, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34396488

RESUMO

Clostridium butyricum (C. butyricum) is a probiotic that could promote animal growth and protect gut health. So far, current studies mainly keep up with the basic biological functions of C. butyricum, missing the effective strategy to further improve its protective efficiency. A recent report about C. butyricum alleviating intestinal injury through epidermal growth factor receptor (EGFR) inspired us to bridge this gap by porcine epidermal growth factor (EGF) overexpression. Lacking a secretory overexpression system, we constructed the recombinant strains overexpressing pEGF in C. butyricum for the first time and obtained 4 recombinant strains for highly efficient secretion of pEGF (BC/pPD1, BC/pSPP, BC/pGHF, and BC/pDBD). Compared to the wild-type strain, we confirmed that the expression level ranges of the intestinal development-related genes (Claudin-1, GLUT-2, SUC, GLP2R, and EGFR) and anti-inflammation-related gene (IL-10) in IPECs were upregulated under recombinant strain stimulation, and the growth of Staphylococcus aureus and Salmonella typhimurium was significantly inhibited as well. Furthermore, a particular inhibitor (stattic) was used to block STAT3 tyrosine phosphorylation, resulting in the downregulation on antibacterial effect of recombinant strains. This study demonstrated that the secretory overexpression of pEGF in C. butyricum could upregulate the expression level of EGFR, consequently improving the intestinal protective functions of C. butyricum partly following STAT3 signal activation in IPECs and making it a positive loop. These findings on the overexpression strains pointed out a new direction for further development and utilization of C. butyricum. KEY POINTS: • By 12 signal peptide screening in silico, 4 pEGF overexpression strains of C. butyricum/pMTL82151-pEGF for highly efficient secretion of pEGF were generated for the first time. • The secretory overexpression of pEGF promoted the intestinal development, antimicrobial action, and anti-inflammatory function of C. butyricum. • The overexpressed pEGF upregulated the expression level of EGFR and further magnified the gut protective function of recombinant strains which in turn partly depended on STAT3 signal pathway in IPECs.


Assuntos
Clostridium butyricum , Probióticos , Animais , Fator de Crescimento Epidérmico , Sinais Direcionadores de Proteínas , Transdução de Sinais , Suínos
19.
Environ Sci Pollut Res Int ; 28(42): 59640-59651, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34143387

RESUMO

Copper mine road dust is the major source of dust in mine operations. The dust produced on the road surface is a great hazard to the workers. Aiming at the road dust of an open-pit mine, this paper conducts a physical and chemical analysis of a new type of chemical dust suppressant. It is prepared by using sodium polyacrylate as a binder, sodium carbonate as a moisture absorbent, polyethylene glycol as a water-retaining agent, and alkyl glycoside as a surfactant. Physical and chemical characteristics and dust suppression performance of dust suppressant were tested. The results show that the dust suppressant has a pH of 11.03, a viscosity of 18.5 mPa·s, and a surface tension of 28.1 mN/m. The content of heavy metal ions contained is less than the maximum concentration defined by "The norms for the integrated treatment of copper mine acidic waste water." Under the same temperature condition, the greater the humidity, the stronger the hygroscopicity. Especially when the humidity is 30%, the hygroscopic effect is contrary to water. The dust suppressant also has good anti-evaporation properties, and it could maintain a moisture content of 4% to 5% after being placed at room temperature for 10 days. Compared with water, the dust suppressant has better performance of wind erosion, water erosion, and compression resistance. Under the same conditions, the loss rate of water is 2 times that of the dust suppressant, and the pressure of the dust suppressant sample is about 3 times that of water. The dust suppressant has a much higher dust removal efficiency for all dust and respirable dust than water under the same conditions. Finally, the test results and mechanism of the dust suppression mechanism of the dust suppressant are described and analyzed, which shows that the dust suppressant studied in this paper has good performance and is suitable for road dust prevention.


Assuntos
Poeira , Metais Pesados , Cobre , Poeira/análise , Humanos , Metais Pesados/análise , Mineração , Vento
20.
Environ Sci Pollut Res Int ; 28(37): 51242-51250, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33982250

RESUMO

A bioenhancement strategy for improving the anaerobic degradation efficiency of ship domestic sewage under microaerobic conditions was proposed in this study. Strains Stenotrophomonas sp. MSPP05 and Prevotella sp. MSPP07 with high organic-degrading efficiency and extracellular hydrolase yield were used for the bioenhancement of activated sludge. In batch experiments, the removal rates of chemical oxygen demand and total nitrogen reached 94.5% and 66.9% after 72 h of degradation. The activities of dehydrogenase, extracellular amylase, and protease in the treatment group were 1.2, 1.4, and 2.0 times higher than those in the control group. Microbial community analysis showed that exogenous enhanced strains competed with original microorganisms and became dominant. One-stage continuous stirred tank reactor with bioenhanced activated sludge ran steadily for 90 days with average effluent COD and TN concentrations of 87.5 and 14.6 mg/L. The feasibility of improving organic-degrading efficiency through bioenhancement by using exogenous hydrolase-producing strains was confirmed under microaerobic conditions. This work provided a theoretical basis for improving treatment effects and developing a new technique for ship domestic sewage treatment.


Assuntos
Microbiota , Esgotos , Reatores Biológicos , Navios , Eliminação de Resíduos Líquidos
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