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1.
J Mater Sci Mater Med ; 35(1): 3, 2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-38206387

RESUMEN

The purpose of this study is to explore a storage solution for titanium implants and investigate its osteogenic properties. The commercial pure titanium (cp-Ti) surface and double-etched (SLA) titanium surface specimens were preserved in air, saline, 10 mM Vitamin C (VitC)-containing saline and 100 mM VitC-containing saline storage solutions for 2 weeks. The surface microtopography of titanium was observed by scanning electron microscopy (SEM), the surface elemental compositions of the specimens were analyzed by Raman and X-ray photoelectron spectroscopy (XPS), and water contact angle and surface roughness of the specimens were tested. The protein adsorption capacity of two titanium surfaces after storage in different media was examined by BCA kit. The MC3T3-E1 osteoblasts were cultured on two titanium surfaces after storage in different media, and the proliferation, adhesion and osteogenic differentiation activity of osteoblasts were detected by CCK-8, laser confocal microscope (CLSM) and Western blot. The SEM results indicated that the titanium surfaces of the air group were relatively clean while scattered sodium chloride or VitC crystals were seen on the titanium surfaces of the other three groups. There were no significant differences in the micromorphology of the titanium surfaces among the four groups. Raman spectroscopy detected VitC crystals on the titanium surfaces of two experimental groups. The XPS, water contact angle and surface roughness results suggested that cp-Ti and SLA-Ti stored in 0.9% NaCl and two VitC-containing saline storage solutions possessed less carbon contamination and higher surface hydrophilicity. Moreover, the protein adsorption potentials of cp-Ti and SLA-Ti surfaces were significantly improved under preservation in two VitC-containing saline storage solutions. The results of in vitro study showed that the preservation of two titanium surfaces in 100 mM VitC-containing saline storage solution upregulated the cell adhesion, proliferation, osteogenic related protein expressions of MC3T3-E1 osteoblasts. In conclusion, preservation of cp-Ti and SLA-Ti in 100 mM VitC-containing saline storage solution could effectively reduce carbon contamination and enhance surface hydrophilicity, which was conducive to osteogenic differentiation of osteoblasts.


Asunto(s)
Ácido Ascórbico , Solución Salina , Titanio , Osteogénesis , Carbono , Agua
2.
BMJ Open ; 13(9): e074677, 2023 09 26.
Artículo en Inglés | MEDLINE | ID: mdl-37751958

RESUMEN

INTRODUCTION: Sleep disorders are clinical syndromes of disturbed sleep-wake rhythms and abnormal sleep quality. They have various causes, but their main manifestations are difficulty falling asleep, sleep disruption and daytime fatigue. These are common clinical symptoms in perioperative patients, especially in gynaecological patients. There is a lack of research on the factors influencing perioperative sleep disorders in gynaecological patients. The aim of this study is to assess the prevalence of sleep disorders in gynaecological surgery patients and to analyse the possible factors influencing them to provide new ideas for improving sleep disorders in this patient population. METHODS AND ANALYSIS: This cross-sectional, descriptive and observational survey is planned to include 480 gynaecological day surgery patients. All patients who meet the inclusion criteria are eligible to join the study. The study will record preoperative diagnosis, surgical procedure, duration of surgery, type of anaesthesia, anaesthetic drugs, sleep quality, anxiety and depression levels and pain indices 30 days before and 1, 2, 3 and 30 days after surgery. ETHICS AND DISSEMINATION: The study was approved by the Ethics Committee of Beijing Shijitan Hospital Affiliated with Capital Medical University (Approval Number: sjtkyll-lx-2022(109)) before the start of recruitment. The results of the study will be disseminated through peer-reviewed publications and conference presentations. TRIAL REGISTRATION NUMBER: ChiCTR2200064533.


Asunto(s)
Trastornos del Inicio y del Mantenimiento del Sueño , Trastornos del Sueño-Vigilia , Humanos , Estudios Transversales , Sueño , Trastornos del Sueño-Vigilia/epidemiología
3.
Chempluschem ; 88(9): e202300262, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37551133

RESUMEN

In recent years, the development of electrochemical biosensors for uric acid has made great achievements. Firstly, uric acid electrochemical biosensors were classified according to their reaction mechanism. Then, the reaction mechanism of the uric acid sensor and the application of nano-modified materials were deeply analyzed from the perspective of non-enzyme and enzymes. In this paper, the catalytic oxidation capacity, enzyme adsorption effect, conductivity, robustness, detection range, and detection limit of uric acid sensors were discussed and compared. Finally, the advantages of acid-sensitive electrochemical biosensors were summarized, and the constructive recommendations were proposed for improving the deficiencies of acid biosensors. The potential for further development in this area was also discussed.


Asunto(s)
Técnicas Biosensibles , Ácido Úrico , Oxidación-Reducción
4.
Front Biosci (Landmark Ed) ; 28(6): 109, 2023 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-37395018

RESUMEN

Endometriosis (EMs) is a common gynecological disease with an increasing incidence in recent years. Because of the lack of specific molecular biological indicators in clinical practice, diagnosis is often delayed and the quality of life of patients is seriously reduced. Therefore, the discovery of effective molecular biomarkers is crucial for the early diagnosis and treatment of EMs patients. With the development of high-throughput sequencing technology, the mechanism of lncRNAs in EMs has been increasingly confirmed experimentally. This article summarizes the biological characteristics and functions of EMs-related lncRNAs, and introduces the mechanisms of EMs-related lncRNAs in the context of ceRNAs, in exosomes, under hypoxic conditions, and related antisense RNAs. The mechanism of the most popular imprinted gene H19 and metastasis-associated lung adenocarcinoma transcript 1 in EMs is then introduced. Finally, we explore the challenges of molecular biomarker EMs-related lncRNAs in the diagnosis and treatment of EMs, anticipating their potential value in clinical applications.


Asunto(s)
Progresión de la Enfermedad , Endometriosis , ARN Largo no Codificante , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Endometriosis/genética , Endometriosis/patología , Endometriosis/fisiopatología , Exosomas/genética , Exosomas/metabolismo , ARN sin Sentido/genética , ARN sin Sentido/metabolismo , Hipoxia/genética , Humanos , Animales
5.
J Hazard Mater ; 454: 131487, 2023 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-37148798

RESUMEN

On-site environmental surveillance of viruses is increasingly important for infection prevention and pandemic control. Herein, we report a facile single-tube colorimetric assay for detecting severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) from environmental compartments. Using glycerol as the phase separation additive, reverse transcription recombinase polymerase amplification (RT-RPA), CRISPR-Cas system activation, G-quadruplex (G4) cleavage, and G4-based colorimetric reaction were performed in a single tube. To further simplify the test, viral RNA genomes used for the one-tube assay were obtained via acid/base treatment without further purification. The whole assay from sampling to visual readout was completed within 30 min at a constant temperature without the need for sophisticated instruments. Coupling the RT-RPA to CRISPR-Cas improved the reliability by avoiding false positive results. Non-labeled cost-effective G4-based colorimetric systems are highly sensitive to CRISPR-Cas cleavage events, and the proposed assay reached the limit of detection of 0.84 copies/µL. Moreover, environmental samples from contaminated surfaces and wastewater were analyzed using this facile colorimetric assay. Given its simplicity, sensitivity, specificity, and cost-effectiveness, our proposed colorimetric assay is highly promising for applications in on-site environmental surveillance of viruses.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/diagnóstico , Colorimetría/métodos , Sistemas CRISPR-Cas , Reproducibilidad de los Resultados , Flujo de Trabajo , Sensibilidad y Especificidad , ARN Viral/genética , Técnicas de Amplificación de Ácido Nucleico/métodos
6.
Front Med (Lausanne) ; 10: 1132823, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37056729

RESUMEN

Background: Increasing numbers of studies demonstrated that picosecond lasers (Picos) were effective and safe for melasma. However, A limited number of randomized controlled trials (RCTs) regarding Picos contribute to a modest level of evidence. Topical hydroquinone (HQ) remains to be the first-line therapy. Objective: To compare the efficacy and safety of non-fractional picosecond Nd:YAG laser (PSNYL), non-fractional picosecond alexandrite laser (PSAL), and 2% HQ cream in the treatment of melasma. Method: Sixty melasma patients with Fitzpatrick skin types (FST) III-IV were randomly assigned to the PSNY, PSAL, and HQ groups at a 1:1:1 ratio. Patients in PSNYL and PSAL groups received 3 laser sessions at 4-week intervals. The 2% HQ cream was applied twice daily for 12 weeks in patients of the HQ group. The primary outcome, the melasma area and severity index (MASI) score, was evaluated at weeks 0, 4, 8, 12, 16, 20, and 24. The patient assessment score by quartile rating scale was rated at weeks 12, 16, 20, and 24. Results: Fifty-nine (98.3%) subjects were included in the analysis. Each group showed significant change from baseline in MASI scores from week 4 to week 24. The MASI score in the PSNYL group showed the greatest reduction compared to the PSAL group (p = 0.016) and HQ group (p = 0.018). The PSAL group demonstrated comparable MASI improvement as the HQ group (p = 0.998). The PSNYL group had the highest patient assessment score, followed by the PSAL group and then the HQ group, although only the differences between PSNYL and HQ groups at weeks 12 and 16 were significant. Four patients (6.8%) experienced recurrence. Other unanticipated events were transient and subsided after 1 week to 6 months. Conclusion: The efficacy of non-fractional PSNYL was superior to that of non-fractional PSAL, which was not inferior to 2% HQ, thus non-fractional Picos providing an alternative for melasma patients with FSTs III-IV. The safety profiles of PSNYL, PSAL, and 2% HQ cream were similar. Clinical Trial Registration: https://www.chictr.org.cn/showprojen.aspx?proj=130994, ChiCTR2100050089.

8.
J Food Sci Technol ; 59(12): 4653-4662, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36276517

RESUMEN

In this study, a simple label-free biosensor for Brucella was constructed, which based on the screen-printed carbon electrode (SPCE) modified by Recombinant protein G/gold nanoparticles/graphene oxide (RpG/Au/GO). The impedance responses of the proposed biosensor were measured by electrochemical AC impedance method in Brucella antigen gradient concentration solutions. The results showed that the linear range of this biosensor was from 1.6 × 102 CFU/mL to 1.6 × 108 CFU/mL with the minimum detection limit of 3.2 × 102 CFU/mL (S/N = 3). Moreover, the biosensor for Brucella detection possessed acceptable reproducibility with a relative standard deviation of 5.15% and acceptable stability with a relative standard deviation of 4.68%. The spiked recovery rate in actual pasteurized milk samples was more than 92%. Therefore, the developed biosensor exhibits excellent prospects in the selective quantification detection of Brucella abortus. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-022-05544-8.

9.
World J Clin Cases ; 10(24): 8535-8546, 2022 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-36157824

RESUMEN

BACKGROUND: Post-transarterial chemoembolization (TACE) liver failure occurs frequently in hepatocellular carcinoma (HCC) patients. The identification of predictors for post-TACE liver failure is of great importance for clinical decision-making in this population. AIM: To investigate the occurrence rate and predictive factors of post-TACE liver failure in this retrospective study to provide clues for decision-making regarding TACE procedures in HCC patients. METHODS: The clinical records of HCC patients treated with TACE therapy were reviewed. Baseline clinical characteristics and laboratory parameters of these patients were extracted. Logistic models were used to identify candidates to predict post-TACE liver failure. RESULTS: A total of 199 HCC patients were enrolled in this study, and 70 patients (35.2%) developed post-TACE liver failure. Univariate and multivariate logistic models indicated that microspheres plus gelatin embolization and main tumor size > 5 cm were risk predictors for post-TACE liver failure [odds ratio (OR): 4.4, 95% confidence interval (CI): 1.2-16.3, P = 0.027; OR: 2.3, 95%CI: 1.05-5.3, P = 0.039, respectively]. Conversely, HCC patients who underwent tumor resection surgery before the TACE procedure had a lower risk for post-TACE liver failure (OR: 0.4, 95%CI: 0.2-0.95, P = 0.039). CONCLUSION: Microspheres plus gelatin embolization and main tumor size might be risk factors for post-TACE liver failure in HCC patients, while prior tumor resection could be a favorable factor reducing the risk of post-TACE liver failure.

10.
Environ Microbiol Rep ; 14(6): 873-885, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-35925018

RESUMEN

The Qaidam Basin on the northern Tibetan Plateau, China, is one of the driest deserts at high elevations, and it has been considered a representative Mars analogue site. Despite recent advances in the diversity of microbial communities in the Qaidam Basin, our understanding of their genomic information, functional potential and adaptive strategies remains very limited. Here, we conducted a combination of physicochemical and metagenomic analyses to investigate the taxonomic composition and adaptive strategies of microbial life in the regolith across the Qaidam Basin. 16S ribosomal RNA (rRNA) gene-based and metagenomic analyses both reveal that microbial communities in the Qaidam Basin are dominated by the bacterial phylum Actinobacteria. The low levels of moisture and organic carbon contents appear to have essential constraints on microbial biomass and diversity. A total of 50 high-quality metagenome-assembled genomes were reconstructed and analysed. Our results reveal the potential of microorganisms to use ambient trace gases to meet energy and carbon needs in this nutrient-limited desert. Furthermore, we find that DNA repair mechanisms and protein protection are likely essential for microbial life in response to stressors of hyperaridity, intense ultraviolet radiation and tremendous temperature fluctuations in this Mars analogue. These findings shed light on the diversity and survival strategies of microbial life inhabiting Mar-like environments, which provide implications for potential life on early Mars.


Asunto(s)
Bacterias , Rayos Ultravioleta , Tibet , ARN Ribosómico 16S/genética , Bacterias/genética , China , Carbono
11.
J Mater Sci Mater Med ; 33(6): 44, 2022 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-35575837

RESUMEN

This study investigated the corrosion susceptibility of pure titanium under uric acid exposure for 7 days based on surface analysis. The prepared pure titanium specimens, exposed to different concentrations of uric acid, were examined for surface microstructure, surface element composition and surface wettability using scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and static contact angle measurement, respectively. The corrosion behaviors of titanium specimens were measured by open-circuit potential (OCP), electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization. The titanium ion release from the prepared specimens, which were immersed in Hank's balanced salt solution (HBSS) containing different amount of uric acid, was measured by inductively coupled plasma atomic emission spectrometry (ICP-AES). More irregular pitting holes were observed on titanium surfaces exposed to a high concentration of uric acid, and XPS analyses revealed that the amount of titanium dioxide (TiO2) decreased. Titanium surfaces pre-treated with high uric acid became more hydrophobic. Furthermore, the results of OCP and potentiodynamic polarization tests showed increased corrosion susceptibility of titanium samples, while EIS data indicated more active corrosion behavior of titanium materials. The high concentration of uric acid also induced titanium ion release. High concentration of uric acid negatively influenced the surface characteristics and corrosion properties of titanium materials, which destroyed the titanium oxide film barrier. High uric acid exposure increased corrosion susceptibility of pure titanium specimens and accelerated titanium ion release. Graphical abstract.


Asunto(s)
Titanio , Ácido Úrico , Corrosión , Ensayo de Materiales , Espectroscopía de Fotoelectrones , Propiedades de Superficie , Titanio/química
12.
Microbiol Resour Announc ; 11(1): e0103121, 2022 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-35023778

RESUMEN

Magnetosome gene clusters (MGCs), which are responsible for magnetosome biosynthesis and organization in magnetotactic bacteria (MTB), are the key to deciphering the mechanisms and evolutionary origin of magnetoreception, organelle biogenesis, and intracellular biomineralization in bacteria. Here, we report the development of MagCluster, a Python stand-alone tool for efficient exploration of MGCs from large-scale (meta)genomic data.

13.
Biomed Mater ; 17(1)2021 11 19.
Artículo en Inglés | MEDLINE | ID: mdl-34731839

RESUMEN

In this study, we established a procedure to prepare a Semaphorin4D (SEMA4D)-immobilized titanium surface and explored its effects on macrophage behaviors in an endothelial cell/macrophage indirect coculture model. The SEMA4D-bovine serum albumin complex was immobilized onto a preprocessed poly L-lysine titanium surface through NaOH hydrothermal treatment and self-assembly technology. All titanium specimens were examined for surface microstructure, surface element composition, and surface wettability by field emission scanning electron microscopy, x-ray photoelectron spectroscopy (XPS), and water contact angle measurement, respectively. Subsequently, we constructed an endothelial cell/macrophage indirect coculture model and evaluated the activation of NF-κB signaling pathway and the expression of proinflammatory cytokines (TNFα, IL-6, and IL-1ß) in macrophages. In XPS analysis, the SEMA4D-immobilized titanium surface appeared as a loose porous structure covered with uniform film, which exhibited better hydrophilicity than the control smooth titanium surface. In the indirect coculture model, SEMA4D attenuated the activation of NF-κB signaling pathway of lipopolysaccharide-stimulated THP-1 macrophages, thereby downregulating the expression of proinflammatory cytokines in macrophages. In conclusion, SEMA4D could be immobilized on titanium surfaces through NaOH hydrothermal treatment and self-assembly technology. Meanwhile, SEMA4D immobilization altered the characteristics of the titanium surfaces, which negatively regulated macrophage behaviors in the endothelial cell/macrophage indirect coculture model.


Asunto(s)
Macrófagos , Titanio , Antiinflamatorios/farmacología , Antígenos CD , Técnicas de Cocultivo , Células Endoteliales , Macrófagos/metabolismo , Semaforinas , Propiedades de Superficie , Titanio/química
14.
Bioengineered ; 12(1): 8233-8246, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34592890

RESUMEN

The gut microbiota system plays a vital role in liver diseases. This study aimed to address the diversity of gut microbiota and its correlations with clinical parameters in healthy individuals, chronic liver disease (CLD), and hepatocellular carcinoma (HCC) patients. Fecal specimens of nine healthy individuals, 11 CLD, and 21 HCC were collected. The diversity of gut microbiota was examined by PCR and Illumina MiSeq sequencing and analyzed using 16S rRNA gene sequencing database. The correlations between gut microbiota and the clinical parameters of participants were also addressed. Compared to healthy individuals, Firmicutes at a phylum level decreased in CLD and HCC patients and Proteobacteria increased (p < 0.05). The composition of Blautia on a genus level in CLD and HCC patients significantly decreased compared to healthy controls (p < 0.05). Firmicutes composition was negatively associated with age and number of males (p < 0.05) and was positively associated with monocytes, high-density lipoprotein cholesterol (HDL-C), and estimated glomerular filtration rate (eGFR) levels (p < 0.05). At a genus level, Blautia composition was negatively associated with cirrhosis, age, and number of males (p < 0.01), while it was positively associated with red blood cells (RBCs), triglycerides, HDL-C, and lymphocyte levels (p < 0.05). Conclusively, there was a significant compositional difference in gut microbiota in CLD and HCC patients compared with healthy subjects. Firmicutes and Blautia in gut microbiota system lessened in CLD and HCC patients. Clinical biochemical parameters have an impact on the diversity of gut microbiota in liver diseases.


Asunto(s)
Carcinoma Hepatocelular/microbiología , Clostridiales/clasificación , Firmicutes/clasificación , Hepatopatías/microbiología , Neoplasias Hepáticas/microbiología , Adulto , Anciano , Estudios de Casos y Controles , Clostridiales/genética , Clostridiales/aislamiento & purificación , Heces/microbiología , Femenino , Firmicutes/genética , Firmicutes/aislamiento & purificación , Microbioma Gastrointestinal , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , ARN Ribosómico 16S/genética , Análisis de Secuencia de ARN , Caracteres Sexuales , Adulto Joven
15.
Front Microbiol ; 12: 690052, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34385986

RESUMEN

Magnetotactic bacteria (MTB) are a group of microbes that biomineralize membrane-bound, nanosized magnetite (Fe3O4), and/or greigite (Fe3S4) crystals in intracellular magnetic organelle magnetosomes. MTB belonging to the Nitrospirae phylum can form up to several hundreds of Fe3O4 magnetosome crystals and dozens of sulfur globules in a single cell. These MTB are widespread in aquatic environments and sometimes account for a significant proportion of microbial biomass near the oxycline, linking these lineages to the key steps of global iron and sulfur cycling. Despite their ecological and biogeochemical importance, our understanding of the diversity and ecophysiology of magnetotactic Nitrospirae is still very limited because this group of MTB remains unculturable. Here, we identify and characterize two previously unknown MTB populations within the Nitrospirae phylum through a combination of 16S rRNA gene-based and genome-resolved metagenomic analyses. These two MTB populations represent distinct morphotypes (rod-shaped and coccoid, designated as XYR, and XYC, respectively), and both form more than 100 bullet-shaped magnetosomal crystals per cell. High-quality draft genomes of XYR and XYC have been reconstructed, and they represent a novel species and a novel genus, respectively, according to their average amino-acid identity values with respect to available genomes. Accordingly, the names Candidatus Magnetobacterium cryptolimnobacter and Candidatus Magnetomicrobium cryptolimnococcus for XYR and XYC, respectively, were proposed. Further comparative genomic analyses of XYR, XYC, and previously reported magnetotactic Nitrospirae reveal the general metabolic potential of this MTB group in distinct microenvironments, including CO2 fixation, dissimilatory sulfate reduction, sulfide oxidation, nitrogen fixation, or denitrification processes. A remarkably conserved magnetosome gene cluster has been identified across Nitrospirae MTB genomes, indicating its putative important adaptive roles in these bacteria. Taken together, the present study provides novel insights into the phylogenomic diversity and ecophysiology of this intriguing, yet poorly understood MTB group.

16.
ACS Nano ; 15(8): 13307-13318, 2021 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-34297528

RESUMEN

Metal selenides are considered as a group of promising candidates as the anode material for sodium-ion batteries due to their high theoretical capacity. However, the intrinsically low electrical and ionic conductivities as well as huge volume change during the charge-discharge process give rise to an inferior sodium storage capability, which severely hinders their practical application. Herein, we fabricated In2Se3/CoSe2 hollow nanorods composed of In2Se3/CoIn2/CoSe2 by growing cobalt-based zeolitic imidazolate framework ZIF-67 on the surface of indium-based metal-organic framework MIL-68, followed by in situ gaseous selenization. Because of the CoIn2 alloy phase in between In2Se3 and CoSe2, a heterostructure consisting of two alloy/selenide interfaces has been successfully constructed, offering synergistically enhanced electrical conductivity, Na diffusion process, and structural stability, in comparison to the single CoIn2-free interface with only two metal selenides. As expected, this nanoconstruction delivers a high reversible capacity of 297.5 and 205.5 mAh g-1 at 5 and 10 A g-1 after 2000 cycles, respectively, and a superior rate performance of 371.6 mAh g-1 at even 20 A g-1.

17.
Microbiome ; 8(1): 152, 2020 10 30.
Artículo en Inglés | MEDLINE | ID: mdl-33126926

RESUMEN

BACKGROUND: The discovery of membrane-enclosed, metabolically functional organelles in Bacteria has transformed our understanding of the subcellular complexity of prokaryotic cells. Biomineralization of magnetic nanoparticles within magnetosomes by magnetotactic bacteria (MTB) is a fascinating example of prokaryotic organelles. Magnetosomes, as nano-sized magnetic sensors in MTB, facilitate cell navigation along the local geomagnetic field, a behaviour referred to as magnetotaxis or microbial magnetoreception. Recent discovery of novel MTB outside the traditionally recognized taxonomic lineages suggests that MTB diversity across the domain Bacteria are considerably underestimated, which limits understanding of the taxonomic distribution and evolutionary origin of magnetosome organelle biogenesis. RESULTS: Here, we perform the most comprehensive metagenomic analysis available of MTB communities and reconstruct metagenome-assembled MTB genomes from diverse ecosystems. Discovery of MTB in acidic peatland soils suggests widespread MTB occurrence in waterlogged soils in addition to subaqueous sediments and water bodies. A total of 168 MTB draft genomes have been reconstructed, which represent nearly a 3-fold increase over the number currently available and more than double the known MTB species at the genome level. Phylogenomic analysis reveals that these genomes belong to 13 Bacterial phyla, six of which were previously not known to include MTB. These findings indicate a much wider taxonomic distribution of magnetosome organelle biogenesis across the domain Bacteria than previously thought. Comparative genome analysis reveals a vast diversity of magnetosome gene clusters involved in magnetosomal biogenesis in terms of gene content and synteny residing in distinct taxonomic lineages. Phylogenetic analyses of core magnetosome proteins in this largest available and taxonomically diverse dataset support an unexpectedly early evolutionary origin of magnetosome biomineralization, likely ancestral to the origin of the domain Bacteria. CONCLUSIONS: These findings expand the taxonomic and phylogenetic diversity of MTB across the domain Bacteria and shed new light on the origin and evolution of microbial magnetoreception. Potential biogenesis of the magnetosome organelle in the close descendants of the last bacterial common ancestor has important implications for our understanding of the evolutionary history of bacterial cellular complexity and emphasizes the biological significance of the magnetosome organelle. Video Abstract.


Asunto(s)
Bacterias/clasificación , Bacterias/citología , Magnetosomas/metabolismo , Biogénesis de Organelos , Filogenia , Bacterias/genética , Ecosistema , Genes Bacterianos/genética , Magnetosomas/genética
18.
Microbiol Resour Announc ; 9(35)2020 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-32855242

RESUMEN

Magnetotactic bacteria represent a valuable model system for the study of microbial biomineralization and magnetotaxis. Here, we report two metagenome-assembled genome sequences of uncultivated magnetotactic bacteria belonging to the order Magnetococcales These genomes contain nearly complete magnetosome gene clusters responsible for magnetosome biomineralization.

19.
Soft Matter ; 16(44): 10029-10045, 2020 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-32696801

RESUMEN

Self-assembled peptide-based nanomaterials have exhibited wide application potential in the fields of materials science, nanodevices, biomedicine, tissue engineering, biosensors, energy storage, environmental science, and others. Due to their porous structure, strong mechanical stability, high biocompatibility, and easy functionalization, three-dimensional self-assembled peptide hydrogels revealed promising potential in bio-related applications. To present the advances in this interesting topic, we present a review on the synthesis and functionalization of peptide hydrogels, as well as their applications in drug delivery, antibacterial materials, cell culture, biomineralization, bone tissue engineering, and biosensors. Specifically, we focus on the fabrication methods of peptide hydrogels through physical, chemical, and biological stimulations. In addition, the functional design of peptide hydrogels by incorporation with polymers, DNA, protein, nanoparticles, and carbon materials is introduced and discussed in detail. It is expected that this work will be helpful not only for the design and synthesis of various peptide-based nanostructures and nanomaterials, but also for the structural and functional tailoring of peptide-based nanomaterials to meet specific demands.


Asunto(s)
Técnicas Biosensibles , Nanoestructuras , Hidrogeles , Péptidos , Ingeniería de Tejidos
20.
Environ Sci Pollut Res Int ; 27(10): 10802-10810, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31950412

RESUMEN

Sediments core within the Yangtze River Estuary was collected for metal and grain size analysis. The vertical distribution characteristics of eight metals along the core were investigated based on 137Cs and 210Pb radionuclide dating. The sediment was mainly composed of sand and silt. The metals concentrations were Al, 4.67-6.83; Fe, 2.3-3.94; Mn, 0.046-0.07; Cr, 69.5-103; Cu, 14.3-32.1; Zn, 47.3-96.7; Cd, 0.037-0.212; Pb, 13.7-23; Ni, 18.8-38.9 (mg·kg-1, except Al, Fe, and Mn as %), respectively. Geoaccumulation indexes (Igeo) indicated that Cu, Zn, and Pb were of pollution-free level; Cd, Cr, and Ni were in a slight polluted level. Based on potential ecological risk factors (EI), Cd posed a moderate risk to the local environment. Correlation analysis showed that Fe, Al, and Mn had a close association with Cu, Zn, Pb, and Ni at p < 0.01. Clay was significantly correlated with other metals except Cr and Cd.


Asunto(s)
Metales Pesados/análisis , Contaminantes Químicos del Agua/análisis , China , Monitoreo del Ambiente , Estuarios , Sedimentos Geológicos , Medición de Riesgo , Ríos
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