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1.
Heliyon ; 9(4): e15359, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37089360

RESUMEN

Polypropylene mesh, integrated in N95 respirators and surgical masks that are widely used in the current crisis of COVID-19, filters aerosols via electrostatics in addition to the physical block. However, any contact to water such as storage under high humidity, exposure to exhaling breath, and washing in water removes its charges and thus compromises its filtering efficiency. We developed a desk top device based on a Cockcroft-Walton's voltage multiplier that can restore the electrostatic charge of surgical masks within 1 min and recover the filtering efficiency of the polypropylene mesh from 87% to 97%. The device is easy to operate and safe, thus may be applied for the reuse of surgical masks towards reducing the plastic wastes.

2.
Rev Sci Instrum ; 94(1): 015113, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-36725615

RESUMEN

In recent years, people have become more interested in using acoustics to locate equipment in intelligent human-computer interfaces (HCI). However, existing acoustic locating systems have poor compatibility with smart devices. To achieve millimeter-level accuracy, most systems require large microphone spacing, complex algorithms, and a high cost. In this paper, we propose a new HCI system, MilliLoc, to achieve millimeter-level real-time acoustic locating. Our first contribution is to design a high-performance and convenient microphone array. It has a high sampling rate of 96 kHz, real-time complete dataflow, and is compatible with any smart device. The second contribution is to propose an improved generalized cross-correlation phase transform method with simplicity and real-time capability. Even if the signal-to-noise ratio is not high enough, it can still estimate the time delay accurately. We combine the microphone array with the algorithm to illustrate the implementation of MilliLoc. Experiments show that MilliLoc has a median 2D accuracy of 7.2 mm in a 60 cm sector area and achieves millimeter-level locating.

3.
Dev Dyn ; 252(4): 536-546, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36577717

RESUMEN

BACKGROUND: Hox genes encode transcription factors that are important for establishing the body plan. Hoxa5 is a member of the mammalian Hox5 paralogous group that regulates the patterning and morphology of the cervical-thoracic region of the axial skeleton. Hoxa5 also plays crucial functions in lung morphogenesis. RESULTS: We generated a Hoxa5eGFP reporter mouse line using CRISPR technology, allowing real-time visualization of Hoxa5 expression. Hoxa5eGFP recapitulates reported embryonic Hoxa5 mRNA expression patterns. Specifically, Hoxa5eGFP can be visualized in the developing mouse neural tube, somites, lung, diaphragm, foregut, and midgut, among other organs. In the stomach, posteriorly biased Hoxa5eGFP expression correlates with a drastic morphological reduction of the corpus in Hox5 paralogous mutants. Expression of Hoxa5eGFP in the lung continues in all lung fibroblast populations through postnatal and adult stages. CONCLUSIONS: We identified cell types that express Hoxa5 in postnatal and adult mouse lungs, including various fibroblasts and vascular endothelial cells. This reporter line will be a powerful tool for studies of the function of Hoxa5 during mouse development, homeostasis, and disease processes.


Asunto(s)
Células Endoteliales , Proteínas de Homeodominio , Ratones , Animales , Células Endoteliales/metabolismo , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Factores de Transcripción/metabolismo , Pulmón , Genes Homeobox , Organogénesis/genética , Fosfoproteínas/genética , Mamíferos/metabolismo
5.
Front Cell Dev Biol ; 9: 767454, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34901011

RESUMEN

Hox genes encode transcription factors that are critical for embryonic skeletal patterning and organogenesis. The Hoxa5, Hoxb5, and Hoxc5 paralogs are expressed in the lung mesenchyme and function redundantly during embryonic lung development. Conditional loss-of-function of these genes during postnatal stages leads to severe defects in alveologenesis, specifically in the generation of the elastin network, and animals display bronchopulmonary dysplasia (BPD) or BPD-like phenotype. Here we show the surprising results that mesenchyme-specific loss of Hox5 function at adult stages leads to rapid disruption of the mature elastin matrix, alveolar enlargement, and an emphysema-like phenotype. As the elastin matrix of the lung is considered highly stable, adult disruption of the matrix was not predicted. Just 2 weeks after deletion, adult Hox5 mutant animals show significant increases in alveolar space and changes in pulmonary function, including reduced elastance and increased compliance. Examination of the extracellular matrix (ECM) of adult Tbx4rtTA; TetOCre; Hox5a f a f bbcc lungs demonstrates a disruption of the elastin network although the underlying fibronectin, interstitial collagen and basement membrane appear unaffected. An influx of macrophages and increased matrix metalloproteinase 12 (MMP12) are observed in the distal lung 3 days after Hox5 deletion. In culture, fibroblasts from Hox5 mutant lungs exhibit reduced adhesion. These findings establish a novel role for Hox5 transcription factors as critical regulators of lung fibroblasts at adult homeostasis.

6.
Mol Brain ; 14(1): 161, 2021 11 06.
Artículo en Inglés | MEDLINE | ID: mdl-34742316

RESUMEN

Parkinson's disease (PD) is a multi-system neurodegenerative disorder. Patients with PD often suffer chronic pain. In the present study, we investigated motor, sensory and emotional changes in three different PD mice models. We found that 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treatment caused significant changes in all measurements. Mechanical hypersensitivity of PD model induced by MPTP peaked at 3 days and persisted for at least 14 days. Using Fos transgenic mice, we found that neurons in the anterior cingulate cortex (ACC) were activated after MPTP treatment. Inhibiting ACC by bilateral microinjection of muscimol significantly reduced mechanical hypersensitivity and anxiety-like responses. By contrast, MPTP induced motor deficit was not affected, indicating ACC activity is mostly responsible for sensory and emotional changes. We also investigated excitatory synaptic transmission and plasticity using brain slices of MPTP treated animals. While L-LTP was blocked or significantly reduced. E-LTP was not significantly affected in slices of MPTP treated animals. LTD induced by repetitive stimulation was not affected. Furthermore, we found that paired-pulse facilitation and spontaneous release of glutamate were also altered in MPTP treated animals, suggesting presynaptic enhancement of excitatory transmission in PD. Our results suggest that ACC synaptic transmission is enhanced in the animal model of PD, and cortical excitation may play important roles in PD related pain and anxiety.


Asunto(s)
Dolor Crónico , Enfermedad de Parkinson , Animales , Dolor Crónico/complicaciones , Modelos Animales de Enfermedad , Giro del Cíngulo/fisiología , Humanos , Ratones , Ratones Endogámicos C57BL , Neuronas , Transmisión Sináptica/fisiología
7.
Elife ; 82019 10 30.
Artículo en Inglés | MEDLINE | ID: mdl-31663848

RESUMEN

CRISPR/Cas systems are widely used to knock out genes by inducing indel mutations, which are prone to genetic compensation. Complex genome modifications such as knockin (KI) might bypass compensation, though difficult to practice due to low efficiency. Moreover, no 'two-in-one' KI strategy combining conditional knockout (CKO) with fluorescent gene-labeling or further allele-labeling has been reported. Here, we developed a dual-cassette-donor strategy and achieved one-step and efficient generation of dual-function KI alleles at tbx5a and kctd10 loci in zebrafish via targeted insertion. These alleles display fluorescent gene-tagging and CKO effects before and after Cre induction, respectively. By introducing a second fluorescent reporter, geno-tagging effects were achieved at tbx5a and sox10 loci, exhibiting CKO coupled with fluorescent reporter switch upon Cre induction, enabling tracing of three distinct genotypes. We found that LiCl purification of gRNA is critical for highly efficient KI, and preselection of founders allows the efficient germline recovery of KI events.


Asunto(s)
Alelos , Edición Génica/métodos , Técnicas de Inactivación de Genes/métodos , Coloración y Etiquetado/métodos , Pez Cebra/genética , Animales , Genotipo , Factores de Transcripción/genética , Proteínas de Pez Cebra/genética
8.
Appl Environ Microbiol ; 84(13)2018 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-29703735

RESUMEN

Efficient root colonization is a prerequisite for application of plant growth-promoting (PGP) bacteria in improving health and yield of agricultural crops. We have recently identified an endophytic bacterium, Pantoea alhagi LTYR-11Z, with multiple PGP properties that effectively colonizes the root system of wheat and improves its growth and drought tolerance. To identify novel regulatory genes required for wheat colonization, we screened an LTYR-11Z transposon (Tn) insertion library and found cra to be a colonization-related gene. By using transcriptome (RNA-seq) analysis, we found that transcriptional levels of an eps operon, the ydiV gene encoding an anti-FlhD4C2 factor, and the yedQ gene encoding an enzyme for synthesis of cyclic dimeric GMP (c-di-GMP) were significantly downregulated in the Δcra mutant. Further studies demonstrated that Cra directly binds to the promoters of the eps operon, ydiV, and yedQ and activates their expression, thus inhibiting motility and promoting exopolysaccharide (EPS) production and biofilm formation. Consistent with previous findings that Cra plays a role in transcriptional regulation in response to carbon source availability, the activating effects of Cra were much more pronounced when LTYR-11Z was grown within a gluconeogenic environment than when it was grown within a glycolytic environment. We further demonstrate that the ability of LTYR-11Z to colonize wheat roots is modulated by the availability of carbon sources. Altogether, these results uncover a novel strategy utilized by LTYR-11Z to achieve host colonization in response to carbon nutrition in the environment, in which Cra bridges a connection between carbon metabolism and colonization capacity of LTYR-11Z.IMPORTANCE Rapid and appropriate response to environmental signals is crucial for bacteria to adapt to competitive environments and to establish interactions with their hosts. Efficient colonization and persistence within the host are controlled by various regulatory factors that respond to specific environmental cues. The most common is nutrient availability. In this work, we unraveled the pivotal role of Cra in regulation of colonization ability of Pantoea alhagi LTYR-11Z in response to carbon source availability. Moreover, we identified three novel members of the Cra regulon involved in EPS synthesis, regulation of flagellar biosynthesis, and synthesis of c-di-GMP and propose a working model to explain the Cra-mediated regulatory mechanism that links carbon metabolism to host colonization. This study elucidates the regulatory role of Cra in bacterial attachment and colonization of plants, which raises the possibility of extending our studies to other bacteria associated with plant and human health.


Asunto(s)
Proteínas Bacterianas/metabolismo , Carbono/metabolismo , Sequías , Pantoea/metabolismo , Proteínas Represoras/metabolismo , Triticum/metabolismo , Triticum/microbiología , Proteínas Bacterianas/genética , Biopelículas , Proteínas Portadoras , GMP Cíclico/metabolismo , Endófitos/metabolismo , Regulación Bacteriana de la Expresión Génica , Interacciones Microbiota-Huesped/genética , Interacciones Microbiota-Huesped/fisiología , Operón , Pantoea/genética , Raíces de Plantas/microbiología , Polisacáridos Bacterianos , Regiones Promotoras Genéticas , Regulón , Proteínas Represoras/genética , Transcriptoma
9.
Int J Syst Evol Microbiol ; 67(10): 4111-4115, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28901898

RESUMEN

A Gram-reaction-positive, facultatively anaerobic, rod-shaped and non-motile bacterial strain, designated TEYR-7T, was isolated from the leaves of Sinopodophyllum hexandrum collected from the Qinling Mountains in Shaanxi Province, northwest China. Growth of strain TEYR-7T occurred at 15-37 °C (optimum, 28-30 °C), at pH 6.0-9.0 (optimum, pH 7.0) and in the presence of 0-3 % (w/v) NaCl (optimum, 0-1 %). Propionate and acetate were produced from glucose fermentation. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain TEYR-7T was a member of the phylum Actinobacteria, exhibiting the highest sequence similarity to Propioniciclava tarda DSM 22130T (94.3 %). The only respiratory quinone detected in strain TEYR-7T was menaquinone MK-9(H4) and the major cellular fatty acids (>10 %) were anteiso-C15 : 0 and C16 : 0. The polar lipid profile consisted of phosphatidylglycerol, diphosphatidylglycerol, two unidentified glycolipids, an unidentified phospholipid and three unidentified lipids. The genomic DNA G+C content was 71.2 mol%. meso-Diaminopimelic acid was detected in the peptidoglycan. On the basis of data from the present polyphasic taxonomic study, strain TEYR-7T is considered to represent a novel species of the genus Propioniciclava, for which the name Propioniciclava sinopodophylli sp. nov. is proposed. The type strain is TEYR-7T (=CCTCC AB 2015257T=KCTC 33808T).


Asunto(s)
Berberidaceae/microbiología , Filogenia , Hojas de la Planta/microbiología , Propionibacteriaceae/clasificación , Técnicas de Tipificación Bacteriana , Composición de Base , Pared Celular/química , China , ADN Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Grasos/química , Glucolípidos/química , Hibridación de Ácido Nucleico , Peptidoglicano/química , Fosfolípidos/química , Propionibacteriaceae/genética , Propionibacteriaceae/aislamiento & purificación , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Vitamina K 2/análogos & derivados , Vitamina K 2/química
10.
Int J Syst Evol Microbiol ; 67(3): 589-595, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27902261

RESUMEN

A novel indole-3-acetic acid-producing bacterium, designated TEGT-2T, was isolated from the roots of Sinopodophyllum hexandrum collected from the Qinling Mountains in shaanxi province, northwestern China, and was subjected to a taxonomic study by using a polyphasic approach. Cells of strain TEGT-2T were Gram-stain-positive, strictly aerobic, endospore-forming rods and motile by means of peritrichous flagella. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain TEGT-2T was a member of the genus Paenibacillus, exhibiting the highest sequence similarity to Paenibacillus pectinilyticus KCTC 13222T (97.9 %), Paenibacillus frigoriresistens CCTCC AB 2011150T (97.3 %), Paenibacillus ferrarius CCTCC AB 2013369T (96.9 %) and Paenibacillus alginolyticus NBRC 15375T (96.5 %). The only menaquinone detected was MK-7, and the major fatty acid was anteiso-C15 : 0. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, two unidentified aminophospholipids, two unidentified phospholipids, an unidentified aminolipid and two unidentified lipids. meso-Diaminopimelic acid was detected in the peptidoglycan. The DNA G+C content was 46.6 mol%. DNA-DNA relatedness values for strain TEGT-2T with respect to its closest phylogenetic relatives Paenibacilluspectinilyticus KCTC 13222T and Paenibacillus. frigoriresistens CCTCC AB 2011150T were lower than 40 %. Based on the phenotypic, phylogenetic and genotypic data, strain TEGT-2T is considered to represent a novel species of the genus Paenibacillus, for which the name Paenibacillus qinlingensis sp. nov. is proposed. The type strain is TEGT-2T (=CCTCC AB 2015258T=KCTC 33806T).


Asunto(s)
Berberidaceae/microbiología , Ácidos Indolacéticos/metabolismo , Paenibacillus/clasificación , Filogenia , Raíces de Plantas/microbiología , Técnicas de Tipificación Bacteriana , Composición de Base , Pared Celular/química , China , ADN Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Grasos/química , Hibridación de Ácido Nucleico , Paenibacillus/genética , Paenibacillus/aislamiento & purificación , Peptidoglicano/química , Fosfolípidos/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Vitamina K 2/análogos & derivados , Vitamina K 2/química
11.
Int J Syst Evol Microbiol ; 66(12): 4993-4999, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27565539

RESUMEN

A Gram-stain-positive, strictly aerobic, rod-shaped, motile and endospore-forming bacterial strain, designated TEGR-3T, was isolated from the roots of Sinopodophyllum hexandrum collected from the Qinling Mountains in Shaanxi Province, China. Strain TEGR-3T produced siderophores and hydrolysed aesculin, starch and CM-cellulose. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain TEGR-3T was a member of the genus Paenibacillus, exhibiting the highest sequence similarity to Paenibacillus endophyticus LMG 27297T (97.3 %) and Paenibacillus castaneae DSM 19417T (97.3 %). MK-7 was the only menaquinone detected and anteiso-C15 : 0 and C16 : 0 were the major fatty acids. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, two unidentified aminophospholipids, two unidentified phospholipids and an unidentified lipid. The cell-wall peptidoglycan contained meso-diaminopimelic acid as the diagnostic diamino acid. The DNA G+C content was 45.2 mol%. DNA-DNA relatedness values for strain TEGR-3T with respect to its closest phylogenetic relatives Paenibacillus endophyticus LMG 27297T and Paenibacillus castaneae DSM 19417T were lower than 40 %. Based on the phenotypic, phylogenetic and genotypic data, strain TEGR-3T is considered to represent a novel species of the genus Paenibacillus, for which the name Paenibacillus sinopodophylli sp. nov. is proposed. The type strain is TEGR-3T (=CCTCC AB 2016047T=KCTC 33807T).


Asunto(s)
Berberidaceae/microbiología , Paenibacillus/clasificación , Filogenia , Raíces de Plantas/microbiología , Sideróforos/biosíntesis , Técnicas de Tipificación Bacteriana , Composición de Base , Pared Celular/química , China , ADN Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Grasos/química , Hibridación de Ácido Nucleico , Paenibacillus/genética , Paenibacillus/aislamiento & purificación , Peptidoglicano/química , Fosfolípidos/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Vitamina K 2/análogos & derivados , Vitamina K 2/química
12.
Biotechnol Lett ; 38(7): 1221-8, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27053080

RESUMEN

OBJECTIVES: To investigate mycothiol peroxidase (MPx) of Corynebacterium glutamicum that is a novel CysGPx family peroxidase using both the mycoredoxin and thioredoxin reducing systems as proton donors for peroxide detoxification and may be involved in the relief of acid stress. RESULTS: A Δmpx mutant exhibited significantly decreased resistance to acid stress and markedly increased accumulation of reactive oxygen species (ROS) and protein carbonylation levels in vivo. Over-expression of mpx increased the resistance of C. glutamicum to acid stress by reducing ROS accumulation. The stress-responsive extracytoplasmic function-sigma (ECF-σ) factor, SigH, mediated acid-induced expression of mpx in the wild-type under acid conditions, which in turn directly contributed to tolerance to acid stress. CONCLUSION: MPx is essential for combating acid stress by reducing intracellular ROS levels induced by acid stress in C. glutamicum, which adds a new dimension to the general physiological functions of CysGPx.


Asunto(s)
Corynebacterium glutamicum/enzimología , Cisteína/metabolismo , Glicopéptidos/metabolismo , Inositol/metabolismo , Peroxidasas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Ácidos/farmacología , Corynebacterium glutamicum/efectos de los fármacos , Carbonilación Proteica , Factor sigma/metabolismo
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