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1.
Nat Commun ; 15(1): 6789, 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39117673

RESUMEN

Oil reservoirs, being one of the significant subsurface repositories of energy and carbon, host diverse microbial communities affecting energy production and carbon emissions. Viruses play crucial roles in the ecology of microbiomes, however, their distribution and ecological significance in oil reservoirs remain undetermined. Here, we assemble a catalogue encompassing viral and prokaryotic genomes sourced from oil reservoirs. The catalogue comprises 7229 prokaryotic genomes and 3,886 viral Operational Taxonomic Units (vOTUs) from 182 oil reservoir metagenomes. The results show that viruses are widely distributed in oil reservoirs, and 85% vOTUs in oil reservoir are detected in less than 10% of the samples, highlighting the heterogeneous nature of viral communities within oil reservoirs. Through combined microcosm enrichment experiments and bioinformatics analysis, we validate the ecological roles of viruses in regulating the community structure of sulfate reducing microorganisms, primarily through a virulent lifestyle. Taken together, this study uncovers a rich diversity of viruses and their ecological functions within oil reservoirs, offering a comprehensive understanding of the role of viral communities in the biogeochemical cycles of the deep biosphere.


Asunto(s)
Biodiversidad , Metagenoma , Yacimiento de Petróleo y Gas , Virus , Yacimiento de Petróleo y Gas/virología , Yacimiento de Petróleo y Gas/microbiología , Virus/genética , Virus/clasificación , Virus/aislamiento & purificación , Metagenoma/genética , Microbiota/genética , Genoma Viral/genética , Filogenia , Bacterias/genética , Bacterias/clasificación , Bacterias/aislamiento & purificación , Metagenómica
2.
Proc Natl Acad Sci U S A ; 121(35): e2317182121, 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39172793

RESUMEN

From microbes to humans, organisms perform numerous tasks for their survival, including food acquisition, migration, and reproduction. A complex biological task can be performed by either an autonomous organism or by cooperation among several specialized organisms. However, it remains unclear how autonomy and cooperation evolutionarily switch. Specifically, it remains unclear whether and how cooperative specialists can repair deleted genes through direct genetic exchange, thereby regaining metabolic autonomy. Here, we address this question by experimentally evolving a mutualistic microbial consortium composed of two specialists that cooperatively degrade naphthalene. We observed that autonomous genotypes capable of performing the entire naphthalene degradation pathway evolved from two cooperative specialists and dominated the community. This evolutionary transition was driven by the horizontal gene transfer (HGT) between the two specialists. However, this evolution was exclusively observed in the fluctuating environment alternately supplied with naphthalene and pyruvate, where mutualism and competition between the two specialists alternated. The naphthalene-supplied environment exerted selective pressure that favors the expansion of autonomous genotypes. The pyruvate-supplied environment promoted the coexistence and cell density of the cooperative specialists, thereby increasing the likelihood of HGT. Using a mathematical model, we quantitatively demonstrate that environmental fluctuations facilitate the evolution of autonomy through HGT when the relative growth rate and carrying capacity of the cooperative specialists allow enhanced coexistence and higher cell density in the competitive environment. Together, our results demonstrate that cooperative specialists can repair deleted genes through a direct genetic exchange under specific conditions, thereby regaining metabolic autonomy.


Asunto(s)
Naftalenos , Naftalenos/metabolismo , Transferencia de Gen Horizontal , Evolución Biológica , Simbiosis , Consorcios Microbianos/genética , Consorcios Microbianos/fisiología , Genotipo
3.
J Orthop Surg Res ; 19(1): 499, 2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39175032

RESUMEN

BACKGROUND: Unicompartmental knee arthroplasty (UKA) has been proved to be a successful treatment for osteoarthritis patients. However, the stress shielding caused by mismatch in mechanical properties between human bones and artificial implants remains as a challenging issue. This study aimed to properly design a bionic porous tibial implant and evaluate its biomechanical effect in reconstructing stress transfer pathway after UKA surgery. METHODS: Voronoi structures with different strut sizes and porosities were designed and manufactured with Ti6Al4V through additive manufacturing and subjected to quasi-static compression tests. The Gibson-Ashby model was used to relate mechanical properties with design parameters. Subsequently, finite element models were developed for porous UKA, conventional UKA, and native knee to evaluate the biomechanical effect of tibial implant with designed structures during the stance phase. RESULTS: The internal stress distribution on the tibia plateau in the medial compartment of the porous UKA knee was found to closely resemble that of the native knee. Furthermore, the mean stress values in the medial regions of the tibial plateau of the porous UKA knee were at least 44.7% higher than that of the conventional UKA knee for all subjects during the most loading conditions. The strain shielding reduction effect of the porous UKA knee model was significant under the implant and near the load contact sites. For subject 1 to 3, the average percentages of nodes in bone preserving and building region (strain values range from 400 to 3000 µm/m) of the porous UKA knee model, ranging from 68.7 to 80.5%, were higher than that of the conventional UKA knee model, ranging from 61.6 to 68.6%. CONCLUSIONS: The comparison results indicated that the tibial implant with designed Voronoi structure offered better biomechanical functionality on the tibial plateau after UKA. Additionally, the model and associated analysis provide a well-defined design process and dependable selection criteria for design parameters of UKA implants with Voronoi structures.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Análisis de Elementos Finitos , Prótesis de la Rodilla , Diseño de Prótesis , Estrés Mecánico , Artroplastia de Reemplazo de Rodilla/métodos , Humanos , Porosidad , Tibia/cirugía , Fenómenos Biomecánicos , Titanio , Aleaciones
4.
ChemSusChem ; : e202400808, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39163552

RESUMEN

Developing active sites with flexibility and diversity is crucial for single atom catalysts (SACs) towards sustainable nitrogen fixation at ambient conditions. Herein, the effects of doping main group metal elements (MGM) on the stability, catalytic activity, and selectivity of vanadium-based SACs is systematically investigated based on density functional theory calculations. It is found that the catalytic activity of V site can be significantly enhanced by the synergistic effect between MGM and vanadium atoms. More importantly, a volcano curve between the catalytic activity and the adsorption free energy of NNH* can be established, in which V-Pb dimer embedded on N-coordinated graphene (VPb-NG) exhibits optimal NRR activity due to its location at the top of volcano. Further analysis of electronic structures reveals that the unoccupancy ratio (eg/t2g) of V site is dramatically increased by the strong d-p orbital hybridization between V and Pb atoms, subsequently, N2 is activated to a larger extent. These interesting findings may provide a new path for designing active sites in SACs with excellent performance.

5.
AMB Express ; 14(1): 76, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38942930

RESUMEN

Rhizopus arrhizus is a saprotrophic, sometimes clinically- and industrially-relevant mold (Mucorales) and distributed worldwide, suggesting it can assimilate a broad spectrum of substrates. Here, 69 strains of R. arrhizus were investigated by using the Biolog FF MicroPlate for the profiles of utilizing 95 carbon and nitrogen substrates. The study showed that most R. arrhizus strains were similar in average well color development (AWCD) and substrate richness (SR). Nevertheless, 13 strains were unique in principal component analyses, heatmap, AWCD, and SR analyses, which may imply a niche differentiation within R. arrhizus. The species R. arrhizus was able to utilize all the 95 carbon and nitrogen substrates, consistent with the hypothesis of a great metabolic diversity. It possessed a substrate preference of alcohols, and seven substrates were most frequently utilized, with N-acetyl-D-galactosamine and L-phenylalanine ranking at the top of the list. Eight substrates, especially L-arabinose and xylitol, were capable of promoting sporulation and being applied for rejuvenating degenerated strains. By phenotyping R. arrhizus strains in carbon and nitrogen assimilation capacity, this study revealed the extent of intra-specific variability and laid a foundation for estimating optimum substrates that may be useful for industrial applications.

6.
Front Microbiol ; 15: 1402807, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38800748

RESUMEN

Pigs are widely used as animal models in various studies related to humans. The interaction between the gut microbiota and the host has significant effects on the host's health and disease status. However, although there have been many studies investigating the pig gut microbiota, the findings have been inconsistent due to variations in rearing conditions. Interactions between the gut microbiota and host have not been fully explored in pigs. Specific pathogen-free (SPF) pigs are ideal non-primate large animals to study the interactions between the gut microbiota and the host. In this study, we performed high-throughput sequencing analysis of the gut microbiota and the gut tissue transcriptome of six SPF pigs to provide a systematic understanding of the composition, function, and spatial distribution of gut microbiota in SPF pigs. We identified significant differences in microbial diversity and functionality among different gastrointestinal tract sites. Metagenomics data analysis revealed significant differences in alpha diversity and beta diversity of microbiota in different gastrointestinal sites of SPF pigs. Additionally, transcriptomic data indicated significant differences in gene expression as well as KEGG and GO functional enrichment between the small intestine and large intestine. Furthermore, by combining microbial metagenomics and host transcriptomics analyses, specific correlations were found between gut microbiota and host genes. These included a negative correlation between the TCN1 gene and Prevotella dentalis, possibly related to bacterial metabolic pathways involving vitamin B12, and a positive correlation between the BDH1 gene and Roseburia hominis, possibly because both are involved in fatty acid metabolism. These findings lay the groundwork for further exploration of the co-evolution between the microbiota and the host, specifically in relation to nutrition, metabolism, and immunity. In conclusion, we have elucidated the diversity of the gut microbiota in SPF pigs and conducted a detailed investigation into the interactions between the gut microbiota and host gene expression. These results contribute to our understanding of the intricate dynamics between the gut microbiota and the host, offering important references for advancements in life science research, bioproduct production, and sustainable development in animal husbandry.

7.
Artículo en Inglés | MEDLINE | ID: mdl-38770602

RESUMEN

Objective: To evaluate the efficacy and safety of ultrasound-guided acupotomy (UgA) for the treatment of thoracodorsal myofascial pain syndrome (TDMPS) and monitor its mid-term efficacy at 3 months after treatment. Methods: A 3-week, evaluator-blinded randomized clinical trial was conducted among 100 patients with TDMPS (visual analogue scale [VAS] score > 3) in the outpatient clinic of the Department of Orthopaedics of the Second Affiliated Hospital of Anhui University of Traditional Chinese Medicine, with a 3-month follow-up starting after completion of treatment. These patients were randomly assigned to receive UgA (n = 50) or oral celecoxib (n = 50). Recruitment was conducted between January 2021 and July 2022. The primary outcome was the VAS score, and the secondary outcomes included the Oswestry Disability Index (ODI), Pain Anxiety Symptoms Scale (PASS), and TNF-α and IL-1ß levels. Outcome data were collected at baseline, week 3 (post-treatment) and week 15 (follow-up). Results: Compared with that in the celecoxib group, the pain in the UgA group was alleviated more strongly, with an adjusted mean group difference of -0.69 (95% CI,-1.07 to -0.31 after multiple imputation) at week 3 and -1.96 (95% CI,-2.33 to -1.59 after multiple imputation) at week 15 (p < 0.001 for overall group × time interaction). Both groups exhibited improvements in the ODI and PASS scores at weeks 3 and 15, but these improvements were significantly greater in the UgA group (p < 0.05). At week 3, the TNF-α and IL-1 levels were significantly lower in both groups, but celecoxib was more effective (p < 0.05). Results from analyses with multilevel multiple imputation for missingness were similar. Conclusion: UgA led to greater and safer alleviation of pain, dysfunction, and pain anxiety in patients treated with TDMPS than did celecoxib and had a durable 3-month efficacy but was inferior to celecoxib in reducing the level of inflammatory factors. These findings may prompt clinicians to recommend UgA as an alternative and supplementary therapy for pain management in patients with TDMPS.

8.
MycoKeys ; 105: 203-216, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38818111

RESUMEN

In the present study, two new Conidiobolus s.s. species were described relying on the morphological studies and phylogenetic analysis utilizing nuclear large subunit of rDNA (nucLSU), mitochondrial small subunit of rDNA (mtSSU), and elongation-factor-like gene (EFL) sequences. Conidiobolusjiangxiensissp. nov. is distinguished by its short primary conidiophores, a feature not commonly observed in other Conidiobolus s.s. species. Conversely, Conidiobolusmarcoconidiussp. nov. is characterized by larger primary conidia and the emergence of 2-5 secondary conidia from each branched secondary conidiophores. Additionally, the taxonomic reassessment of C.polyspermus confirms its distinct status within the genus Conidiobolus s.s. Moreover, molecular analyses, incorporating the nucLSU, mtSSU, and EFL sequences, provide robust support for the phylogenetic placement of the two newly described species and the taxonomic identity of C.polyspermus. This investigation contributes valuable insights into the species diversity of Conidiobolaceae in China, enhancing our understanding of the taxonomy within this fungal family.

9.
Biomacromolecules ; 25(6): 3554-3565, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38729918

RESUMEN

Hydrogels are considered as a potential cartilage replacement material based on their structure being similar to natural cartilage, which are of great significance in repairing cartilage defects. However, it is difficult for the existing hydrogels to combine the high load bearing and low friction properties (37 °C) of cartilage through sample methods. Herein, we report a facile and new fabrication strategy to construct the PNIPAm/EYL hydrogel by using the macrophase separation of supersaturated N-isopropylacrylamide (NIPAm) monomer solution to promote the formation of liposomes from egg yolk lecithin (EYL) and asymmetric template method. The PNIPAm/EYL hydrogels possess a relatively high compressive strength (more than 12 MPa), fracture energy (9820 J/m2), good fatigue resistance, lubricating properties, and excellent biocompatibility. Compared with the PNIPAm hydrogel, the friction coefficient (COF 0.046) of PNIPAm/EYL hydrogel is reduced by 50%. More importantly, the COF (0.056) of PNIPAm/EYL hydrogel above lower critical solution temperature (LCST) does not increase significantly, exhibiting heat-tolerant lubricity. The finite element analysis further proves that PNIPAm/EYL hydrogel can effectively disperse the applied stress and dissipate energy under load conditions. This work not only provides new insights for the design of high-strength lubricating hydrogels but also lays a foundation for the treatment of cartilage injury as a substitute material.


Asunto(s)
Resinas Acrílicas , Hidrogeles , Hidrogeles/química , Resinas Acrílicas/química , Animales , Calor , Lubricantes/química , Cartílago/química , Lecitinas/química , Fuerza Compresiva , Liposomas/química , Yema de Huevo/química , Materiales Biocompatibles/química
10.
Adv Sci (Weinh) ; 11(26): e2400594, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38689503

RESUMEN

Proteolysis targeting chimeras (PROTACs) have emerged as a promising strategy for drug discovery and exploring protein functions, offering a revolutionary therapeutic modality. Currently, the predominant approach to PROTACs discovery mainly relies on an empirical design-synthesis-evaluation process involving numerous cycles of labor-intensive synthesis-purification and bioassay data collection. Therefore, the development of innovative methods to expedite PROTAC synthesis and exploration of chemical space remains highly desired. Here, a direct-to-biology strategy is reported to streamline the synthesis of PROTAC libraries on plates, enabling the seamless transfer of reaction products to cell-based bioassays without the need for additional purification. By integrating amide coupling and light-induced primary amines and o-nitrobenzyl alcohols cyclization (PANAC) photoclick chemistry into a plate-based synthetic process, this strategy produces PROTAC libraries with high efficiency and structural diversity. Moreover, by employing this platform for PROTACs screening, we smoothly found potent PROTACs effectively inhibit triple-negative breast cancer (TNBC) cell growth and induce rapid, selective targeted degradation of cyclin-dependent kinase 9 (CDK9). The study introduces a versatile platform for assembling PROTACs on plates, followed by direct biological evaluation. This approach provides a promising opportunity for high-throughput synthesis of PROTAC libraries, thereby enhancing the efficiency of exploring chemical space and accelerating the discovery of PROTACs.


Asunto(s)
Descubrimiento de Drogas , Proteolisis , Humanos , Descubrimiento de Drogas/métodos , Proteolisis/efectos de los fármacos , Línea Celular Tumoral , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Quimera Dirigida a la Proteólisis
11.
Artículo en Inglés | MEDLINE | ID: mdl-38686814

RESUMEN

OBJECTIVE: To explore the relationship between two-year changes in muscle strength and cartilage according to knee pain in mild and moderate knee Osteoarthritis (OA). DESIGN: 279 participants were retrospectively obtained from the Osteoarthritis Initiative. Western Ontario McMaster University (WOMAC) and Knee Injury and Osteoarthritis Outcome Score were used to assess pain and function. Five muscles strength (maximum extensor and flexor, normalized maximum extensor and flexor, and extensor/flexor ratio) were measured from isometric strength test. Menisci and cartilage volumes were measured from MRI to assess two-year of OA progression. RESULTS: Mild and moderate knee OA progression was characterized by patellofemoral cartilage loss and meniscal degeneration. For WOMAC pain >2 participants, decrease in extensor strength and normalized extensor strength were positively correlated with medial meniscus volume loss (r = 0.261, P = 0.021; r = 0.232, P = 0.041, respectively). The extensor/flexor ratio changes were positively associated with WOMAC function changes (r = 0.291, P = 0.013) over two-year. CONCLUSION: The study observed a positive correlation between quadriceps strength decrease and medial meniscus degeneration in mild and moderate knee OA patients with WOMAC pain >2. These findings suggested quadriceps-hamstrings balance possibly plays a protective role in knee function for participants with weaker quadriceps and severe pain.

12.
J Biomech ; 166: 112046, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38467079

RESUMEN

Full-length radiographs contain information from which many anatomical parameters of the pelvis, femur, and tibia may be derived, but only a few anatomical parameters are used for musculoskeletal modeling. This study aimed to develop a fully automatic algorithm to extract anatomical parameters from full-length radiograph to generate a musculoskeletal model that is more accurate than linear scaled one. A U-Net convolutional neural network was trained to segment the pelvis, femur, and tibia from the full-length radiograph. Eight anatomic parameters (six for length and width, two for angles) were automatically extracted from the bone segmentation masks and used to generate the musculoskeletal model. Sørensen-Dice coefficient was used to quantify the consistency of automatic bone segmentation masks with manually segmented labels. Maximum distance error, root mean square (RMS) distance error and Jaccard index (JI) were used to evaluate the geometric accuracy of the automatically generated pelvis, femur and tibia models versus CT bone models. Mean Sørensen-Dice coefficients for the pelvis, femur and tibia 2D segmentation masks were 0.9898, 0.9822 and 0.9786, respectively. The algorithm-driven bone models were closer to the 3D CT bone models than the scaled generic models in geometry, with significantly lower maximum distance error (28.3 % average decrease from 24.35 mm) and RMS distance error (28.9 % average decrease from 9.55 mm) and higher JI (17.2 % average increase from 0.46) (P < 0.001). The algorithm-driven musculoskeletal modeling (107.15 ± 10.24 s) was faster than the manual process (870.07 ± 44.79 s) for the same full-length radiograph. This algorithm provides a fully automatic way to generate a musculoskeletal model from full-length radiograph that achieves an approximately 30 % reduction in distance errors, which could enable personalized musculoskeletal simulation based on full-length radiograph for large scale OA populations.


Asunto(s)
Redes Neurales de la Computación , Tibia , Radiografía , Tibia/diagnóstico por imagen , Fémur/diagnóstico por imagen , Pelvis , Procesamiento de Imagen Asistido por Computador
13.
Mitochondrial DNA B Resour ; 9(3): 332-337, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38476836

RESUMEN

The complete mitochondrial genome of the entomophthoroid fungus Capillidium rhysosporum (strain no.: ATCC 12588) was sequenced using next-generation sequencing technology. The assembled circular genome has a length of 46,756 base pairs with a GC content of 27.06%. Gene prediction identified 15 core protein-coding genes (PCGs), two rRNA genes, and 27 tRNA genes. Phylogenetic analysis confirmed that C. rhysosporum belongs to the Zoopagomycota clade and is closely related to C. heterosporum. This study presents the second complete mitochondrial genome within the family Capillidiaceae, contributing to the mitochondrial DNA database of entomophthoroid fungi.

14.
Environ Sci Pollut Res Int ; 31(15): 22560-22575, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38407709

RESUMEN

Conventional inorganic coagulants (Al, Fe) and Al/Fe-based covalently bonded flocculants (CAFMs) had different hydrolysis species at different pHs, which subsequently led to differences in their binding sites and complexation ability with humic acid (HA). Studying the binding sites and interactions between CAFMs, AlCl3 (Al), and FeCl3 (Fe) hydrolysates and HA molecules is critical to understanding the coagulation mechanism. The results found that CAFM 0.6, Al, and AlCl3 combined FeCl3 (Al/Fe) removed more than 90% of HA at pH 6, and CAFMs showed higher HA removal rate than that of Al, Fe, and Al/Fe under the same reaction conditions. The flocs of CAFMs contained abundant -NH2/OH as well as the large particle size, compact structure, and excellent settling performance. The hydrolyzed species of Al and Fe were predominantly Alb and Feb at pH 6, but the hydrolyzed species of CAFMs were primarily (Al + Fe)c. Moreover, the hydrolyzed species of Al and Al/Fe were found to complex with HA functional groups such as -COOH, C = O, C-H/C-C, C = C, and C-OH to form ligand bonds, while the hydrolyzed species (Al + Fe)c of CAFMs could deeply interact with HA functional groups including C-O, -COOH, C = O, C-H/C-C, C = C, and C-OH by the adsorption and sweeping.


Asunto(s)
Sustancias Húmicas , Purificación del Agua , Sustancias Húmicas/análisis , Purificación del Agua/métodos , Cloruros , Compuestos Férricos/química
15.
Cell Syst ; 15(3): 275-285.e4, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38401538

RESUMEN

Unraveling the mechanisms governing the diversity of ecological communities is a central goal in ecology. Although microbial dispersal constitutes an important ecological process, the effect of dispersal on microbial diversity is poorly understood. Here, we sought to fill this gap by combining a generalized Lotka-Volterra model with experimental investigations. Our model showed that emigration increases the diversity of the community when the immigration rate crosses a defined threshold, which we identified as Ineutral. We also found that at high immigration rates, emigration weakens the relative abundance of fast-growing species and thus enhances the mass effect and increases the diversity. We experimentally confirmed this finding using co-cultures of 20 bacterial strains isolated from the soil. Our model further showed that Ineutral decreases with the increase of species pool size, growth rate, and interspecies interaction. Our work deepens the understanding of the effects of dispersal on the diversity of natural communities.


Asunto(s)
Microbiota , Modelos Biológicos , Microbiota/genética , Emigración e Inmigración , Bacterias
16.
J Vis Exp ; (204)2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38372363

RESUMEN

DNA double-strand breaks (DSBs) represent the most perilous DNA lesions, capable of inducing substantial genetic information loss and cellular demise. In response, cells employ two primary mechanisms for DSB repair: nonhomologous end joining (NHEJ) and homologous recombination (HR). Quantifying the efficiency of NHEJ and HR separately is crucial for exploring the relevant mechanisms and factors associated with each. The NHEJ assay and HR assay are established methods used to measure the efficiency of their respective repair pathways. These methods rely on meticulously designed plasmids containing a disrupted green fluorescent protein (GFP) gene with recognition sites for endonuclease I-SceI, which induces DSBs. Here, we describe the extrachromosomal NHEJ assay and HR assay, which involve co-transfecting HEK-293T cells with EJ5-GFP/DR-GFP plasmids, an I-SceI expressing plasmid, and an mCherry expressing plasmid. Quantitative results of NHEJ and HR efficiency are obtained by calculating the ratio of GFP-positive cells to mCherry-positive cells, as counted by flow cytometry. In contrast to chromosomally integrated assays, these extrachromosomal assays are more suitable for conducting comparative investigations involving multiple established stable cell lines.


Asunto(s)
Roturas del ADN de Doble Cadena , Reparación del ADN , Humanos , Proteínas Fluorescentes Verdes/genética , Células HEK293 , Recombinación Homóloga , Reparación del ADN por Unión de Extremidades
17.
Macromol Rapid Commun ; 45(8): e2300683, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38237945

RESUMEN

Wound healing in movable parts, including the joints and neck, remains a critical challenge due to frequent motions and poor flexibility of dressings, which may lead to mismatching of mechanical properties and poor fitting between dressings and wounds; thus, increasing the risk of bacterial infection. This study proposes a sprayable zwitterionic antibacterial hydrogel with outstanding flexibility and desirable adhesion. This hydrogel precursor is fabricated by combining zwitterionic sulfobetaine methacrylate (SBMA) with poly(sulfobetaine methacrylate-co-dopamine methacrylamide)-modified silver nanoparticles (PSBDA@AgNPs) through robust electrostatic interactions. About 150 s of exposure to UV light, the SBMA monomer polymerizes to form PSB chains entangled with PSBDA@AgNPs, transformed into a stable and adhesion PSB-PSB@Ag hydrogel at the wound site. The resulting hydrogel has adhesive strength (15-38 kPa), large tensile strain (>400%), suitable shape adaptation, and excellent mechanical resilience. Moreover, the hydrogel displays pH-responsive behavior; the acidic microenvironment at the infected wound sites prompts the hydrogel to rapidly release AgNPs and kill bacteria. Further, the healing effect of the hydrogel is demonstrated on the rat neck skin wound, showing improved wound closing rate due to reduced inflammation and enhanced angiogenesis. Overall, the sprayable zwitterionic antibacterial hydrogel has significant potential to promote joint skin wound healing.


Asunto(s)
Antibacterianos , Hidrogeles , Nanopartículas del Metal , Metacrilatos , Plata , Cicatrización de Heridas , Hidrogeles/química , Hidrogeles/farmacología , Hidrogeles/síntesis química , Antibacterianos/química , Antibacterianos/farmacología , Cicatrización de Heridas/efectos de los fármacos , Animales , Plata/química , Plata/farmacología , Ratas , Nanopartículas del Metal/química , Metacrilatos/química , Metacrilatos/farmacología , Staphylococcus aureus/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Pruebas de Sensibilidad Microbiana
18.
Appl Environ Microbiol ; 90(1): e0162523, 2024 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-38168668

RESUMEN

Many Acinetobacter species can grow on n-alkanes of varying lengths (≤C40). AlmA, a unique flavoprotein in these Acinetobacter strains, is the only enzyme proven to be required for the degradation of long-chain (LC) n-alkanes, including C32 and C36 alkanes. Although it is commonly presumed to be a terminal hydroxylase, its role in n-alkane degradation remains elusive. In this study, we conducted physiological, biochemical, and bioinformatics analyses of AlmA to determine its role in n-alkane degradation by Acinetobacter baylyi ADP1. Consistent with previous reports, gene deletion analysis showed that almA was vital for the degradation of LC n-alkanes (C26-C36). Additionally, enzymatic analysis revealed that AlmA catalyzed the conversion of aliphatic 2-ketones (C10-C16) to their corresponding esters, but it did not conduct n-alkane hydroxylation under the same conditions, thus suggesting that AlmA in strain ADP1 possesses Baeyer-Villiger monooxygenase (BVMO) activity. These results were further confirmed by bioinformatics analysis, which revealed that AlmA was closer to functionally identified BVMOs than to hydroxylases. Altogether, the results of our study suggest that LC n-alkane degradation by strain ADP1 possibly follows a novel subterminal oxidation pathway that is distinct from the terminal oxidation pathway followed for short-chain n-alkane degradation. Furthermore, our findings suggest that AlmA catalyzes the third reaction in the LC n-alkane degradation pathway.IMPORTANCEMany microbial studies on n-alkane degradation are focused on the genes involved in short-chain n-alkane (≤C16) degradation; however, reports on the genes involved in long-chain (LC) n-alkane (>C20) degradation are limited. Thus far, only AlmA has been reported to be involved in LC n-alkane degradation by Acinetobacter spp.; however, its role in the n-alkane degradation pathway remains elusive. In this study, we conducted a detailed characterization of AlmA in A. baylyi ADP1 and found that AlmA exhibits Baeyer-Villiger monooxygenase activity, thus indicating the presence of a novel LC n-alkane biodegradation mechanism in strain ADP1.


Asunto(s)
Acinetobacter , Oxigenasas de Función Mixta , Oxigenasas de Función Mixta/metabolismo , Alcanos/metabolismo , Oxidación-Reducción , Acinetobacter/genética
19.
Am J Phys Med Rehabil ; 103(7): 603-610, 2024 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-38206636

RESUMEN

OBJECTIVE: The aim of the study is to assess the relationship between walking exercise and medial joint space narrowing progression, symptoms, and knee extensor muscle strength in early knee osteoarthritis patients. METHODS: This nested cohort study within the Osteoarthritis Initiative included participants aged 50 yrs and older with knee osteoarthritis (Kellgren-Lawrence grades 0-2). Walking exercisers were identified using a modified Historical Physical Activity Survey Instrument. Differences in medial joint space narrowing, Knee Injury and Osteoarthritis Outcome Score, and knee extensor muscle strength were evaluated through the three-way analysis of variance. RESULTS: Among 896 participants, 83.4% reported walking exercise. Female walkers showed significant improvements in symptoms (Knee Injury and Osteoarthritis Outcome Score-pain: P < 0.001; Knee Injury and Osteoarthritis Outcome Score-symptom: P < 0.001; Knee Injury and Osteoarthritis Outcome Score-quality of life: P < 0.001; Knee Injury and Osteoarthritis Outcome Score-function, sports, and recreational activities: P = 0.007). Similar results were observed in male walkers (Knee Injury and Osteoarthritis Outcome Score-pain: P < 0.001; Knee Injury and Osteoarthritis Outcome Score-symptom: P < 0.001; Knee Injury and Osteoarthritis Outcome Score-quality of life: P = 0.001; Knee Injury and Osteoarthritis Outcome Score-function, sports, and recreational activities: P = 0.009). Walkers showed significantly increased knee extensor muscle strength at 24 mos (female: P < 0.001; male: P = 0.003). Female nonwalkers had significantly decreased knee extensor muscle strength at 24 mos ( P < 0.001). Walkers showed significant improvement in medial joint space narrowing (odds ratio = 1.1, 95% confidence interval = 1.0-1.2) and Kellgren-Lawrence grade (OR = 1.0, 95% CI = 1.0-1.1) compared with nonwalkers. CONCLUSIONS: Walking exercise prevents structural progression and improves symptoms. Meanwhile, the increased knee extensor muscle strength in all walkers further supports the validity of recommending walking exercises for early-stage knee osteoarthritis patients.


Asunto(s)
Progresión de la Enfermedad , Fuerza Muscular , Osteoartritis de la Rodilla , Caminata , Humanos , Osteoartritis de la Rodilla/fisiopatología , Osteoartritis de la Rodilla/rehabilitación , Femenino , Masculino , Fuerza Muscular/fisiología , Persona de Mediana Edad , Anciano , Caminata/fisiología , Terapia por Ejercicio/métodos , Estudios de Cohortes , Factores Sexuales , Calidad de Vida
20.
Microorganisms ; 12(1)2024 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-38257994

RESUMEN

The fungal order Entomophthorales in the Zoopagomycota includes many fungal pathogens of arthropods. This review explores six genera in the subfamily Erynioideae within the family Entomophthoraceae, namely, Erynia, Furia, Orthomyces, Pandora, Strongwellsea, and Zoophthora. This is the largest subfamily in the Entomophthorales, including 126 described species. The species diversity, global distribution, and host range of this subfamily are summarized. Relatively few taxa are geographically widespread, and few have broad host ranges, which contrasts with many species with single reports from one location and one host species. The insect orders infected by the greatest numbers of species are the Diptera and Hemiptera. Across the subfamily, relatively few species have been cultivated in vitro, and those that have require more specialized media than many other fungi. Given their potential to attack arthropods and their position in the fungal evolutionary tree, we discuss which species might be adopted for biological control purposes or biotechnological innovations. Current challenges in the implementation of these species in biotechnology include the limited ability or difficulty in culturing many in vitro, a correlated paucity of genomic resources, and considerations regarding the host ranges of different species.

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