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1.
Anal Chem ; 96(18): 7065-7072, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38652079

RESUMEN

Protein allostery is commonly observed in vitro. But how protein allostery behaves in cells is unknown. In this work, a protein monomer-dimer equilibrium system was built with the allosteric effect on the binding characterized using NMR spectroscopy through mutations away from the dimer interface. A chemical shift linear fitting method was developed that enabled us to accurately determine the dissociation constant. A total of 28 allosteric mutations were prepared and grouped to negative allosteric, nonallosteric, and positive allosteric modulators. ∼ 50% of mutations displayed the allosteric-state changes when moving from a buffered solution into cells. For example, there were no positive allosteric modulators in the buffered solution but eight in cells. The change in protein allostery is correlated with the interactions between the protein and the cellular environment. These interactions presumably drive the surrounding macromolecules in cells to transiently bind to the monomer and dimer mutational sites and change the free energies of the two species differently which generate new allosteric effects. These surrounding macromolecules create a new protein allostery pathway that is only present in cells.


Asunto(s)
Resonancia Magnética Nuclear Biomolecular , Regulación Alostérica , Mutación , Multimerización de Proteína , Modelos Moleculares
2.
BMC Plant Biol ; 24(1): 684, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39020284

RESUMEN

Malus sieversii, commonly known as wild apples, represents a Tertiary relict plant species and serves as the progenitor of globally cultivated apple varieties. Unfortunately, wild apple populations are facing significant degradation in localized areas due to a myriad of factors. To gain a comprehensive understanding of the nutrient status and spatiotemporal variations of M. sieversii, green leaves were collected in May and July, and the fallen leaves were collected in October. The concentrations of leaf nitrogen (N), phosphorus (P), and potassium (K) were measured, and the stoichiometric ratios as well as nutrient resorption efficiencies were calculated. The study also explored the relative contributions of soil, topographic, and biotic factors to the variation in nutrient traits. The results indicate that as the growing period progressed, the concentrations of N and P in the leaves significantly decreased (P < 0.05), and the concentration of K in October was significantly lower than in May and July. Throughout plant growth, leaf N-P and N-K exhibited hyperallometric relationships, while P-K showed an isometric relationship. Resorption efficiency followed the order of N < P < K (P < 0.05), with all three ratios being less than 1; this indicates that the order of nutrient limitation is K > P > N. The resorption efficiencies were mainly regulated by nutrient concentrations in fallen leaves. A robust spatial dependence was observed in leaf nutrient concentrations during all periods (70.1-97.9% for structural variation), highlighting that structural variation, rather than random factors, dominated the spatial variation. Nutrient resorption efficiencies (NRE, PRE, and KRE) displayed moderate structural variation (30.2-66.8%). The spatial patterns of nutrient traits varied across growth periods, indicating they are influenced by multifactorial elements (in which, soil property showed the highest influence). In conclusion, wild apples manifested differentiated spatiotemporal variability and influencing factors across various leaf nutrient traits. These results provide crucial insights into the spatiotemporal patterns and influencing factors of leaf nutrient traits of M. sieversii at the permanent plot scale for the first time. This work is of great significance for the ecosystem restoration and sustainable management of degrading wild fruit forests.


Asunto(s)
Malus , Nitrógeno , Fósforo , Hojas de la Planta , Potasio , Hojas de la Planta/metabolismo , Malus/metabolismo , Malus/crecimiento & desarrollo , Malus/fisiología , China , Fósforo/metabolismo , Fósforo/análisis , Nitrógeno/metabolismo , Potasio/metabolismo , Potasio/análisis , Bosques , Nutrientes/metabolismo , Nutrientes/análisis , Suelo/química , Frutas/crecimiento & desarrollo , Frutas/metabolismo , Análisis Espacio-Temporal
3.
Small ; : e2402076, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38757424

RESUMEN

High-rate lithium/sodium ion batteries or capacitors are the most promising functional units to achieve fast energy storage that highly depends on charge host materials. Host materials with lamellar structures are a good choice for hybrid charge storage hosts (capacitor or redox type). Emerging layered transition metal carbo-chalcogenides (TMCC) with homogeneous sulfur termination are especially attractive for charge storage. Using density functional theory calculations, six of 30 potential TMCC are screened to be stable, metallic, anisotropic in electronic conduction and mechanical properties due to the lamellar structures. Raman, infrared active modes and frequencies of the six TMCC are well assigned. Interlayer coupling, especially binding energies predict that the bulk layered materials can be easily exfoliated into 2D monolayers. Moreover, Ti2S2C, Zr2S2C are identified as the most gifted Li+/Na+ anode materials with relatively high capacities, moderate volume expansion, relatively low Li+/Na+ migration barriers for batteries or ion-hybrid capacitors. This work provides a foundation for rational materials design, synthesis, and identification of the emerging 2D family of TMCC.

4.
Hum Reprod ; 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38942602

RESUMEN

STUDY QUESTION: Can pregnancy outcomes following fresh elective single embryo transfer (eSET) in gonadotropin-releasing hormone (GnRH) antagonist protocols increase using a gonadotropin (Gn) step-down approach with cessation of GnRH antagonist on the day of hCG administration (hCG day) in patients with normal ovarian response? SUMMARY ANSWER: The modified GnRH antagonist protocol using the Gn step-down approach and cessation of GnRH antagonist on the hCG day is effective in improving live birth rates (LBRs) per fresh eSET cycle. WHAT IS KNOWN ALREADY: Currently, there is no consensus on optimal GnRH antagonist regimens. Studies have shown that fresh GnRH antagonist cycles result in poorer pregnancy outcomes than the long GnRH agonist (GnRHa) protocol. Endometrial receptivity is a key factor that contributes to this phenomenon. STUDY DESIGN, SIZE, DURATION: An open label randomized controlled trial (RCT) was performed between November 2021 and August 2022. There were 546 patients allocated to either the modified GnRH antagonist or the conventional antagonist protocol at a 1:1 ratio. PARTICIPANTS/MATERIALS, SETTING, METHODS: Both IVF and ICSI cycles were included, and the sperm samples used were either fresh or frozen from the partner, or from frozen donor ejaculates. The primary outcome was the LBRs per fresh SET cycle. Secondary outcomes included rates of implantation, clinical and ongoing pregnancy, miscarriage, and ovarian hyperstimulation syndrome (OHSS), as well as clinical outcomes of ovarian stimulation. MAIN RESULTS AND THE ROLE OF CHANCE: Baseline demographic features were not significantly different between the two ovarian stimulation groups. However, in the intention-to-treat (ITT) population, the LBRs in the modified antagonist group were significantly higher than in the conventional group (38.1% [104/273] vs. 27.5% [75/273], relative risk 1.39 [95% CI, 1.09-1.77], P = 0.008). Using a per-protocol (PP) analysis which included all the patients who received an embryo transfer, the LBRs in the modified antagonist group were also significantly higher than in the conventional group (48.6% [103/212] vs. 36.8% [74/201], relative risk 1.32 [95% CI, 1.05-1.66], P = 0.016). The modified antagonist group achieved significantly higher implantation rates, and clinical and ongoing pregnancy rates than the conventional group in both the ITT and PP analyses (P < 0.05). The two groups did not show significant differences between the number of oocytes retrieved or mature oocytes, two-pronuclear zygote (2PN) rates, the number of embryos obtained, blastocyst progression and good-quality embryo rates, early miscarriage rates, or OHSS incidence rates (P > 0.05). LIMITATIONS, REASONS FOR CAUTION: A limitation of our study was that the subjects were not blinded to the treatment allocation in the RCT trial. Only women under 40 years of age who had a good prognosis were included in the analysis. Therefore, use of the modified antagonist protocol in older patients with a low ovarian reserve remains to be investigated. In addition, the sample size for Day 5 elective SET was small, so larger trials will be required to strengthen these findings. WIDER IMPLICATIONS OF THE FINDINGS: The modified GnRH antagonist protocol using the Gn step-down approach and cessation of GnRH antagonist on hCG day improved the LBRs per fresh eSET cycle in normal responders. STUDY FUNDING/COMPETING INTEREST(S): This project was funded by grant 2022YFC2702503 from the National Key Research & Development Program of China and grant 2021140 from the Beijing Health Promotion Association. The authors declare no conflicts of interest. TRIAL REGISTRATION NUMBER: The RCT was registered in the Chinese Clinical Trial Registry; Study Number: ChiCTR2100053453. TRIAL REGISTRATION DATE: 21 November 2021. DATE OF FIRST PATIENT'S ENROLLMENT: 23 November 2021.

5.
J Sci Food Agric ; 104(3): 1553-1563, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37815100

RESUMEN

BACKGROUND: As indigestible carbohydrates, milk oligosaccharides possess various benefits for newborns, mainly through intestinal microbiota, among which 2'-fucosyllactose (2'-FL) is the most predominant milk oligosaccharide. However, knowledge about the fermentative characteristics of 2'-FL in the gut remains limited, especially in the small intestine. The aim of this study is to explore the differential fermentability of 2'-FL by the small and large intestinal microbiota of piglets using fructo-oligosaccharide (FOS) and lactose as controls in an in vitro batch fermentation experiment. During fermentation, microbial composition was characterized along with gas production and short-chain fatty acid production. RESULTS: 2'-Fucosyllactose showed differential fermentability in jejunal and colonic fermentation. Compared with the colon, 2'-FL produced less gas in the jejunum than in the FOS and lactose groups (P < 0.05). Meanwhile, 2'-FL exhibited a different influence on the microbial composition and metabolism in the jejunum and colon compared with FOS and lactose. In the jejunum, compared with the FOS and lactose groups, the 2'-FL group showed a higher abundance of Bacteroides, Prevotella, and Blautia, but a lower abundance of Streptococcus and Lactobacillus (P < 0.05), with a higher level of propionate and a lower level of lactate during fermentation (P < 0.05). In the colon, compared with the FOS and lactose groups, 2'-FL increased the abundance of Blautia, Faecalibacterium, and Lachnospiraceae FCS020, but decreased the abundance of Prevotella_9, Succinivibrio, and Megasphaera (P < 0.05) with an increase in acetate production (P < 0.05). CONCLUSION: Overall, the results suggested that the small intestinal microbiota had the potential to ferment milk oligosaccharides. Meanwhile, in comparison with FOS and lactose, 2'-FL selectively stimulated the growth of propionate-producing bacteria in the jejunum and acetate-producing bacteria in the colon. These results demonstrated the differences in fermentation properties of 2'-FL by small and large intestinal microbiota and provided new evidence for the application of 2'-FL in optimizing gut microbiota. © 2023 Society of Chemical Industry.


Asunto(s)
Microbioma Gastrointestinal , Animales , Porcinos , Fermentación , Propionatos/farmacología , Lactosa/metabolismo , Oligosacáridos/metabolismo , Acetatos/farmacología
6.
Funct Integr Genomics ; 23(2): 170, 2023 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-37209314

RESUMEN

As a toxic heavy metal, cadmium (Cd) is one of the principal pollutants influencing rice productivity and food security. Despite several studies, the underlying mechanism of Cd response in plants remains largely unclear. Dehydrins are part of the late embryogenesis abundant (LEA) family which protect plants against abiotic stresses. In this study, a Cd-responsive LEA gene, OsDHN2, was functionally characterized. The chromosome localization results indicated that OsDHN2 was located on chromosome 2 of rice. Meanwhile, cis-acting elements, such as MBS (MYB binding site involved in drought-inducibility), ARE (anaerobic induction), and ABRE (abscisic acid), were present in the OsDHN2 promoter region. Expression pattern analysis also showed that OsDHN2 expression was induced in both roots and shoots under Cd stress. Overexpression of OsDHN2 improved Cd tolerance and reduced Cd concentration in yeast. Moreover, increased expression levels of SOD1, CTA1, GSH1, or CTT1 were found in transgenic yeast under Cd stress, suggesting the increased antioxidant enzymatic activities. These results suggested that OsDHN2 is a Cd-responsive gene that has the potential to improve resistance to Cd in rice.


Asunto(s)
Cadmio , Oryza , Cadmio/toxicidad , Cadmio/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Oryza/genética , Oryza/metabolismo , Biología Computacional , Regulación de la Expresión Génica de las Plantas
7.
BMC Plant Biol ; 23(1): 586, 2023 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-37993773

RESUMEN

BACKGROUND: Mitochondrial genomes are essential for deciphering the unique evolutionary history of seed plants. However, the rules of their extreme variation in genomic size, multi-chromosomal structure, and foreign sequences remain unresolved in most plant lineages, which further hindered the application of mitogenomes in phylogenetic analyses. RESULTS: Here, we took Dendrobium (Orchidaceae) which shows the great divergence of morphology and difficulty in species taxonomy as the study focus. We first de novo assembled two complete mitogenomes of Dendrobium wilsonii and Dendrobium henanense that were 763,005 bp and 807,551 bp long with multichromosomal structures. To understand the evolution of Dendrobium mitogenomes, we compared them with those of four other orchid species. The results showed great variations of repetitive and chloroplast-derived sequences in Dendrobium mitogenomes. Moreover, the intergenic content of Dendrobium mitogenomes has undergone expansion during evolution. We also newly sequenced mitogenomes of 26 Dendrobium species and reconstructed phylogenetic relationships of Dendrobium based on genomic mitochondrial and plastid data. The results indicated that the existence of chloroplast-derived sequences made the mitochondrial phylogeny display partial characteristics of the plastid phylogeny. Additionally, the mitochondrial phylogeny provided new insights into the phylogenetic relationships of Dendrobium species. CONCLUSIONS: Our study revealed the evolution of Dendrobium mitogenomes and the potential of mitogenomes in deciphering phylogenetic relationships at low taxonomic levels.


Asunto(s)
Dendrobium , Genoma Mitocondrial , Orchidaceae , Filogenia , Orchidaceae/genética , Dendrobium/genética , Genoma Mitocondrial/genética , Genómica/métodos , Secuencia de Bases
8.
Hum Reprod ; 38(Supplement_2): ii34-ii46, 2023 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-37982417

RESUMEN

STUDY QUESTION: How do the types and frequency of chromosome aberrations in couples in central China affect fertility and ART treatment? SUMMARY ANSWER: Men with chromosome aberrations or polymorphisms have an increased risk of semen quality impairment and infertility, and couples affected by reciprocal translocations had a lower pregnancy rate compared with other chromosome aberrations. WHAT IS KNOWN ALREADY: Karyotyping is crucial for patients affected by infertility as chromosome aberrations play an important role in the etiology of male infertility. However, the influence of chromosome aberrations and polymorphisms on sperm motility and morphology remains controversial. Data on ART treatment outcomes in infertile couples affected by chromosome aberrations are insufficient. STUDY DESIGN, SIZE, DURATION: We conducted a retrospective study involving 17 054 patients affected by infertility who underwent karyotyping in our center between January 2020 and May 2022. PARTICIPANTS/MATERIALS, SETTING, METHODS: Karyotyping was performed on 17 054 patients with reproductive failure. All patients were from the central regions of China. The following data were collected from a medical records system using patient identification numbers: couples' ages, history of pregnancy and childbirth, type of infertility, years of infertility, cause of infertility, chromosome karyotypes, semen analysis results, assisted reproductive techniques performed, and treatment outcomes of ART. MAIN RESULTS AND THE ROLE OF CHANCE: The incidence of chromosome aberrations was 2.04%; 2.49% in men and 1.57% in women. By analyzing the relationships between chromosome aberrations/polymorphisms and abnormal semen parameters, we found that there were significantly higher rates of asthenozoospermia, oligospermia, and teratozoospermia among men with Robertsonian translocations and sex chromosomal structural aberrations compared with those with normal karyotypes. Higher rates of asthenozoospermia and teratozoospermia were also observed among men with autosomal reciprocal translocations. The incidence of chromosome aberrations in azoospermic men (13.75%), and in men with cryptozoospermia or severe oligospermia (6.97%) was significantly higher than that in men with mild oligospermia or normospermia (0.88-2.12%). In addition, we found that the progressive movement of sperm is impaired in men with Chromosome 21 polymorphisms compared with men with normal karyotypes (39.46% ± 20.51% vs 48.61% ± 18.76%, P = 0.026). The percentage of morphologically normal forms was lower in the chromosomal polymorphism group than in the normal karyotype group (5.01% ± 2.41% vs 5.59% ± 2.14%, P = 0.001), especially in men with polymorphisms on Chromosome 9 (enlarged Chromosome 9 heterochromatin [9qh+]: 4.48% ± 2.22% vs 5.59% ± 2.14%, P = 0.006; pericentric inversion of Chromosome 9 [inv(9)]: 5.09% ± 3.11% vs 5.59% ± 2.14%, P = 0.008). ART treatment was successful in 36.00% of couples affected by chromosome aberrations. However, couples affected by reciprocal translocations achieved a lower pregnancy rate (24.07%), which may be due to the lower euploidy rates (27.31%) when compared with that in other chromosome aberrations. LIMITATIONS, REASONS FOR CAUTION: First, although the initial cohort was large, chromosome aberrations were identified in a small number of patients. Second, the observational nature of the study design is limiting. Third, the couples affected by infertility in this study were all outpatients that did not undergo identical comprehensive examinations except for karyotyping, leading to the incomplete collection of medical records. Also, the population included in this study mainly focused on couples affected by infertility, which may not be included in the European Association of Urology (EAU) recommendation on male infertility. WIDER IMPLICATIONS OF THE FINDINGS: Men with chromosome aberrations or polymorphisms have an increased risk of semen quality impairment and infertility. Constitutional chromosome analysis is recommended for men affected by infertility and severe oligospermia or azoospermia to facilitate early and appropriate guidance for the most suitable treatment. Carriers of chromosome aberrations can achieve acceptable pregnancy outcomes through IVF. However, couples affected by reciprocal translocations have lower pregnancy rates, and more treatment cycles are needed before a successful pregnancy. A possible explanation may be the fewer euploid embryos obtained. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by Grant 2021YFC2700603 from the National Key Research & Development Program of China. The authors declare no conflicts of interest. TRIAL REGISTRATION NUMBER: N/A.


Asunto(s)
Astenozoospermia , Infertilidad Masculina , Oligospermia , Teratozoospermia , Embarazo , Masculino , Humanos , Femenino , Estudios Retrospectivos , Análisis de Semen , Semen , Motilidad Espermática , Aberraciones Cromosómicas , Translocación Genética , Infertilidad Masculina/genética , Infertilidad Masculina/terapia , Fertilidad
9.
Anim Biotechnol ; 34(9): 4927-4937, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37199180

RESUMEN

This study was to investigate the correlations of myogenic differentiation 1 (MYOD1) gene polymorphisms with carcass traits and its expression with breast muscle development in pigeons. Four SNPs were found in the pigeon MYOD1 gene. Correlation analysis showed that individuals with AA genotype at both SNPs g.2967A > G (p < .01) and g.3044G > A (p < .05) have significantly higher live weight (LW), carcass weight (CW), semi-eviscerated weight (SEW), eviscerated weight (EW) and breast muscle weight (BMW). Moreover, the two SNPs also had the same significant effects on MYOD1 mRNA expression levels in breast muscle of pigeons, ie, the AA genotype showed higher MYOD1 mRNA expression levels. The diameter and cross-section area of muscle fibers continuously increased from 0w to 4w (p < .05), accompanied with the increasing expression of MYOD1 gene, while the density decreased (p < .05) dramatically from 0w to 1w and continuously fell over in the next few weeks (p > .05). What's more, the expression level of MYOD1 gene was positively correlated with a diameter (r = 0.937, p < .05) and cross-sectional area (r = 0.956, p < .01) of myofiber, and negatively correlated with density (r = -0.769, p < .01). The results showed that individuals with AA genotype at both SNPs g.2967A > G and g.3044G > A have showed higher carcass traits (LW, CW, SEW, EW, and BMW) and higher MYOD1 mRNA expression level in breast muscle than AB and BB genotypes. Moreover, the expression level of MYOD1 gene was closely correlated with muscle characteristic traits, indicating variants of MYOD1 gene was closely related to muscle development and could be a potential candidate gene in marker-assisted selection of pigeons.


Asunto(s)
Columbidae , Carne , Humanos , Animales , Columbidae/genética , Fenotipo , Genotipo , Músculos , ARN Mensajero , Polimorfismo de Nucleótido Simple/genética
10.
J Sci Food Agric ; 103(4): 2146-2154, 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36574261

RESUMEN

BACKGROUND: A starch-lipid complex is a new type of resistant starch, which is of great importance for the prevention of chronic diseases such as diabetes. Most starch-lipid complexes usually need to be treated by heating to make them suitable for a variety of applications, and starch-based foods are generally not edible without a heat-treatment process. However, the digestion and structural properties of the starch-lipid complex will be changed after heating. In this study, microwave and conventional heating were used to treat debranched quinoa starch-oleic acid complexes (DQS-OA) with different water addition conditions, and the effects of the two methods on the physicochemical, digestive, and structural properties of DQS-OA were compared. RESULTS: The results of in vitro digestibility showed that the resistant starch content (235.34-269.55 g kg-1 ) of the conventional heating-treated samples was significantly higher than that the microwave-treated samples (141.51-157.99 g kg-1 ). Moreover, after microwave treatment, the short-range molecular order and crystalline structure of DQS-OA were destroyed and the particle size became smaller. In contrast, the thermal stability, enthalpy, and crystallinity of the complexes after conventional heating were improved. The ratio at 1047/1022 cm-1 of complexes has also been increased. CONCLUSION: This study demonstrated that conventional water-bath heating was better than microwave heating in increasing digestion resistance, improving the short-range and long-range molecular order, and promoting the formation of DQS-OA. With an increase in water addition, the influence of microwave or water-bath treatment on the properties of DQS-OA became greater. © 2022 Society of Chemical Industry.


Asunto(s)
Chenopodium quinoa , Almidón , Almidón/química , Ácido Oléico , Almidón Resistente , Microondas , Agua , Calefacción
11.
BMC Plant Biol ; 22(1): 201, 2022 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-35439926

RESUMEN

BACKGROUND: Because chloroplast (cp) genome has more conserved structures than nuclear genome and mitochondrial genome, it is a useful tool in estimating the phylogenetic relationships of plants. With a series of researches for cp genomes, there have been comprehensive understandings about the cp genome features. The genus Bulbophyllum widely distributed in Asia, South America, Australia and other places. Therefore, it is an excellent type genus for studying the effects of geographic isolation. RESULTS: In this study, the cp genomes of nine Bulbophyllum orchids were newly sequenced and assembled using the next-generation sequencing technology. Based on 19 Asian (AN) and eight South American (SA) Bulbophyllum orchids, the cp genome features of AN clade and SA clade were compared. Comparative analysis showed that there were considerable differences in overall cp genome features between two clades in three aspects, including basic cp genome features, SSC/IRB junctions (JSBs) and mutational hotspots. The phylogenetic analysis and divergence time estimation results showed that the AN clade has diverged from the SA clade in the late Oligocene (21.50-30.12 mya). After estimating the occurrence rates of the insertions and deletions (InDels), we found that the change trends of cp genome structures between two clades were different under geographic isolation. Finally, we compared selective pressures on cp genes and found that long-term geographic isolation made AN and SA Bulbophyllum cp genes evolved variably. CONCLUSION: The results revealed that the overall structural characteristics of Bulbophyllum cp genomes diverged during the long-term geographic isolation, and the crassulacean acid metabolism (CAM) pathway may play an important role in the Bulbophyllum species evolution.


Asunto(s)
Genoma del Cloroplasto , Orchidaceae , Asia , Australia , Genoma del Cloroplasto/genética , Orchidaceae/genética , Filogenia
12.
BMC Microbiol ; 22(1): 220, 2022 09 19.
Artículo en Inglés | MEDLINE | ID: mdl-36117157

RESUMEN

BACKGROUND: The widespread use of antibiotics has led to the emergence of many drug-resistant strains; thus, the development of new antibacterial drugs is essential with antimicrobial peptides becoming the focus of research. This study assessed the antibacterial effect of a novel antimicrobial peptide, named LL-1 on Escherichia coli (E.coli) by determining the minimum inhibitory concentration (MIC) and the antibacterial curve. The interaction between LL-1 and E. coli DNA was then detected by nucleic acid gel electrophoresis. The effect of LL-1 on the E. coli cell membrane was assessed by detecting the leakage of ß-galactosidase, nucleic acid and protein. The influence of LL-1 on the intracellular ATP of E. coli was analysed by determining the concentration of intracellular ATP. Finally, the bacteria and colonies of E. coli treated with LL-1 were observed using scanning and transmission electron microscopy. RESULTS: The results suggested that the MIC value was 3.125 µg/ml, and the antibacterial effect was dose-dependent. LL-1 dose-dependently combined with E. coli DNA. LL-1 resulted in the leakage of intracellular ß-galactosidase, nucleic acid and protein, and decreased intracellular ATP concentrations of E. coli. Two MIC of LL-1 caused E. coli to shrink, resulting in a rough surface, plasmolysis, and bacterial adhesion. CONCLUSION: This study indicated that LL-1 had a good bactericidal effect on E. coli by mainly increasing the permeability of the cell membrane, leading to leakage of the intracellular content. This will lay the foundation for an in-depth study on the antibacterial mechanism of LL-1 against E. coli and its clinical application.


Asunto(s)
Infecciones por Escherichia coli , Ácidos Nucleicos , Adenosina Trifosfato/metabolismo , Antibacterianos/metabolismo , Antibacterianos/farmacología , Péptidos Catiónicos Antimicrobianos/química , Péptidos Catiónicos Antimicrobianos/farmacología , Escherichia coli/genética , Infecciones por Escherichia coli/tratamiento farmacológico , Humanos , Ácidos Nucleicos/metabolismo , Ácidos Nucleicos/farmacología , Permeabilidad , beta-Galactosidasa/metabolismo
13.
Ophthalmology ; 129(9): 1014-1021, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35537532

RESUMEN

PURPOSE: To explore whether there is a causal relationship between coffee consumption and primary open-angle glaucoma (POAG). DESIGN: Two-sample Mendelian randomization (MR). PARTICIPANTS: The single-nucleotide polymorphisms (SNPs) associated with coffee consumption (including phenotypes 1 and 2) were selected from a genome-wide association study (GWAS) involving 121 824 individuals of European descent. Coffee intake from the MRC-IEU UK Biobank was also used to identify instruments for coffee intake. Summary-level data for POAG were obtained from the largest publicly available meta-analyses involving 16 677 POAG cases and 199 580 controls of European descent. METHODS: The inverse variance-weighted (IVW) method was the main MR analysis, whereas weighted-median, weighted mode-based estimate (MBE), MR Pleiotropy RESidual Sum and Outlier (PRESSO) test, and MR-Egger regression were used for sensitivity analysis. MAIN OUTCOME MEASURES: Diagnosis of POAG. RESULTS: Three sets of instrumental variables were used to evaluate the causal association between coffee consumption and POAG risk. Results showed that genetically predicted higher coffee consumption phenotype 1 (cups/day) was significantly associated with higher risk of POAG (odds ratio [OR], 1.241; 95% confidence interval [CI], 1.041-1.480; P = 0.016). Genetically predicted higher coffee consumption phenotype 2 (high vs. no/low) was also significantly associated with higher risk of POAG (OR, 1.155; 95% CI, 1.038-1.284; P = 0.008, using the IVW method). Moreover, genetically predicted higher coffee intake from the MRC-IEU UK Biobank OpenGWAS was significantly associated with a higher risk of POAG (OR, 1.727; 95% CI, 1.230-2.425; P = 0.002, using the IVW method). Sensitivity analyses confirmed that the findings were robust to possible pleiotropy. CONCLUSIONS: These findings provide the genetic evidence that higher coffee consumption is associated with a higher risk of POAG. Given that coffee is widely consumed, our findings provide new insights into potential strategies to prevent and manage POAG.


Asunto(s)
Glaucoma de Ángulo Abierto , Análisis de la Aleatorización Mendeliana , Café/efectos adversos , Estudio de Asociación del Genoma Completo , Glaucoma de Ángulo Abierto/epidemiología , Glaucoma de Ángulo Abierto/genética , Humanos , Polimorfismo de Nucleótido Simple
14.
J Sep Sci ; 45(15): 2987-2995, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35642725

RESUMEN

A porous boron nitride with a large surface area was synthesized by a one-step grinding method with melamine, urea, and boric acid as the precursors. The prepared porous boron nitride was used as the fiber coating material for the solid-phase microextraction of seven phthalate esters (diethyl phthalate, diallyl phthalate, diisobutyl phthalate, dibutyl phthalate, butylbenzyl phthalate, dicyclohexyl phthalate, and di-2-ethylhexyl phthalate) prior to their gas chromatography-mass spectrometric detection. The important experimental parameters including the extraction time, extraction temperature, salt concentration, and stirring rate were optimized by both single factor and central composite design methods. Under the optimized experimental conditions, the linear response range for the analytes was from 0.030 to 30.0 µg/L, and the limits of detection were from 0.010 to 0.040 µg/L, respectively. The relative recoveries of the analytes for spiked samples at two concentration levels were 83.0-109% with the relative standard deviations less than 12%. The established method was successfully applied for the determination of the phthalate esters in bottled juice beverage samples.


Asunto(s)
Ésteres , Ácidos Ftálicos , Bebidas/análisis , Compuestos de Boro , Ésteres/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Inmersión , Ácidos Ftálicos/análisis , Porosidad
15.
Ecotoxicol Environ Saf ; 229: 113073, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34923330

RESUMEN

To understand the environmental friendliness and high efficiency of organic materials during remediating soil polluted by heavy metals by assessing the feedback of soil ecosystems after organic materials were put into polluted soil. Incubation research was undertaken to examine the impact of amendments ranging from 0.1% to 3.0% (w/w), including single cow bone meal (BM), single oyster shell meal (OS), and a composite of 50% BM mixed with 50% OS (BO) on soil biochemical properties. The findings revealed that the implementation of BM and OS increased soil pH, the content of certain nutrients, and the activities of catalase (S-CAT), and urease (S-UE) while decreasing the availability of Cd, Pb, Cu, and Zn. Overall, the immobilization effect on Cd and Zn after a 108-day incubation was ranked as follows: BM group > OS group ≥ BO group, and the order of the immobilization effect of Pb and Cu was OS group > BO group > BM group. In addition, the dominant bacterial community flora shifted toward alleviating the re-dissolution of metal ions from the soil and promoting nutrient recycling in soil within 108 days of cultivation. RNA analyses showed that the strongest determinants for microbial communities between BM application and OS application at the genus level were soil pH, CEC, and heavy metal (Cd, Pb). These results increase our understanding of the leaching performance of Cd, Pb, Cu and Zn and the evolution trend of microorganisms when organic amendments remediate heavy metal contaminated soil.


Asunto(s)
Metales Pesados , Ostreidae , Contaminantes del Suelo , Animales , Productos Biológicos , Cadmio/análisis , Bovinos , Ecosistema , Plomo , Metales Pesados/análisis , Minerales , Suelo , Contaminantes del Suelo/análisis , Zinc
16.
BMC Surg ; 22(1): 9, 2022 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-34996403

RESUMEN

BACKGROUND: Bone fibrous dysplasia is a benign disease of bone tissue dysplasia. Vision impairment is the commonest neurological complication of craniofacial fibrous dysplasia. Most of the vision loss caused by craniofacial fibrous dysplasia is usually a gradual process. Very few present with acute visual impairment as described in our case. CASE PRESENTATION: We report a patient with fibrous dysplasia presenting rapidly progressive visual loss in the left eye secondary to bone cyst formation. Transnasal endoscopic surgery guided by navigation with drainage and curettage of this bone cyst and orbital decompression resulted in progressive improvement in visual acuity that returned to normal 1 month post-operatively. CONCLUSIONS: In cases with acute visual loss due to fibrous dysplasia, emergency surgical treatment should be considered to preserve vision. In the surgical approach, navigation-guided nasal endoscopic surgery may be preferred because of its advantages.


Asunto(s)
Displasia Fibrosa Ósea , Complicaciones del Embarazo , Descompresión Quirúrgica , Endoscopía , Displasia Fibrosa Ósea/complicaciones , Displasia Fibrosa Ósea/cirugía , Humanos , Agudeza Visual
17.
Sensors (Basel) ; 22(18)2022 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-36146326

RESUMEN

Unsupervised person re-identification has attracted a lot of attention due to its strong potential to adapt to new environments without manual annotation, but learning to recognise features in disjoint camera views without annotation is still challenging. Existing studies tend to ignore the optimisation of feature extractors in the feature-extraction stage of this task, while the use of traditional losses in the unsupervised learning stage severely affects the performance of the model. Additionally the use of a contrast learning framework in the latest methods uses only a single cluster centre or all instance features, without considering the correctness and diversity of the samples in the class, which affects the training of the model. Therefore, in this paper, we design an unsupervised person-re-identification framework called attention-guided fine-grained feature network and symmetric contrast learning (AFF_SCL) to improve the two stages in the unsupervised person-re-identification task. AFF_SCL focuses on learning recognition features through two key modules, namely the Attention-guided Fine-grained Feature network (AFF) and the Symmetric Contrast Learning module (SCL). Specifically, the attention-guided fine-grained feature network enhances the network's ability to discriminate pedestrians by performing further attention operations on fine-grained features to obtain detailed features of pedestrians. The symmetric contrast learning module replaces the traditional loss function to exploit the information potential given by the multiple samples and maintains the stability and generalisation capability of the model. The performance of the USL and UDA methods is tested on the Market-1501 and DukeMTMC-reID datasets by means of the results, which demonstrate that the method outperforms some existing methods, indicating the superiority of the framework.


Asunto(s)
Identificación Biométrica , Peatones , Atención , Identificación Biométrica/métodos , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Mantenimiento
18.
Int J Mol Sci ; 23(10)2022 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-35628400

RESUMEN

Infantile neuronal ceroid lipofuscinosis (INCL), the most severe form of neuronal ceroid lipofuscinoses, is caused by mutations in the lysosomal enzyme palmitoyl protein thioesterase 1 (PPT1). Typical symptoms of this disease include progressive psychomotor developmental retardation, visual failure, seizures, and premature death. Here, we investigated seizure activity and relevant pathological changes in PPT1 knock-in mice (PPT1 KI). The behavior studies in this study demonstrated that PPT1 KI mice had no significant seizure activity until 7 months of age, and local field potentials also displayed epileptiform activity at the same age. The expression levels of Iba-1 and CD68 demonstrated, by Western blot analysis, the inflammatory cytokine TNF-α content measured with enzyme-linked immunosorbent assay, and the number of microglia demonstrated by immunohistochemistry (IHC) were significantly increased at age of 7 months, all of which indicate microglia activation at an age of seizure onset. The increased expression of GFAP were seen at an earlier age of 4 months, and such an increase reached its peak at age of 6 months, indicating that astrocyte activation precedes microglia. The purinergic P2X7 receptor (P2X7R) is an ATP-sensitive ionic channel that is highly expressed in microglia and is fundamental to microglial activation, proliferation, cytokines release and epilepsy. We show that the ATP concentration in hippocampal tissue in PPT1 KI mice was increased using an enhanced ATP assay kit and demonstrated that the antagonist of P2X7R, A-438079, significantly reduced seizures in PPT1 KI mice. In contrast to glial cell activation and proliferation, a significant reduction in synaptic proteins GABAAR was seen in PPT1 KI mice. These results indicate that seizure in PPT1 KI mice may be associated with microglial activation involved in ATP-sensitive P2X7R signaling and impaired inhibitory neurotransmission.


Asunto(s)
Microglía , Lipofuscinosis Ceroideas Neuronales , Tioléster Hidrolasas , Adenosina Trifosfato , Animales , Citocinas/metabolismo , Modelos Animales de Enfermedad , Inflamación/metabolismo , Inflamación/patología , Ratones , Ratones Noqueados , Microglía/metabolismo , Microglía/patología , Lipofuscinosis Ceroideas Neuronales/patología , Convulsiones/genética , Tioléster Hidrolasas/genética , Tioléster Hidrolasas/metabolismo
19.
J Am Chem Soc ; 143(46): 19606-19613, 2021 11 24.
Artículo en Inglés | MEDLINE | ID: mdl-34766768

RESUMEN

Most proteins perform their functions in cells. How the cellular environment modulates protein interactions is an important question. In this work, electrostatic interactions between protein charges were studied using in-cell nuclear magnetic resonance (NMR) spectroscopy. A total of eight charge pairs were introduced in protein GB3. Compared to the charge pair electrostatic interactions in a buffer, five charge pairs in cells displayed no apparent changes whereas three pairs had the interactions weakened by more than 70%. Further investigation suggests that the transfer free energy is responsible for the electrostatic interaction modulation. Both the transfer free energy of the folded state and that of the unfolded state can contribute to the cellular environmental effect on protein electrostatics, although the latter is generally larger (more negative) than the former. Our work highlights the importance of direct in-cell studies of protein interactions and thus protein function.


Asunto(s)
Antígenos de Carbohidratos Asociados a Tumores/química , Escherichia coli/química , Resonancia Magnética Nuclear Biomolecular , Escherichia coli/citología , Electricidad Estática , Termodinámica
20.
Respir Res ; 21(1): 319, 2020 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-33267895

RESUMEN

BACKGROUND: Exacerbation of chronic obstructive pulmonary disease (COPD) severely impacts the quality of life and causes high mortality and morbidity. COPD is involved with systemic and pulmonary inflammation, which may be attenuated with antidiabetic agents exerting anti-inflammatory effects. Real-world evidence is scant regarding the effects of antidiabetic agents on COPD exacerbation. Accordingly, we conducted a disease risk score (DRS)-matched nested case-control study to systemically assess the association between each class of oral hypoglycemic agents (OHAs) and risk of severe COPD exacerbation in a nationwide COPD population co-diagnosed with diabetes mellitus (DM). METHODS: We enrolled 23,875 COPD patients receiving at least one OHA for management of DM by analyzing the Taiwan National Health Insurance claims database between January 1, 2000, and December 31, 2015. Cases of severe exacerbation were defined as those who had the first hospital admission for COPD. Each case was individually matched with four randomly-selected controls by cohort entry date, DRS (the estimated probability of encountering a severe COPD exacerbation), and COPD medication regimens using the incidence density sampling approach. Conditional logistic regressions were performed to estimate odds ratios (OR) of severe COPD exacerbation for each type of OHAs. RESULTS: We analyzed 2700 cases of severe COPD exacerbation and 9272 corresponding controls after DRS matching. Current use of metformin versus other OHAs was associated with a 15% (adjusted OR [aOR], 0.85; 95% confidence interval [CI] 0.75-0.95) reduced risk of severe COPD exacerbation, whereas the reduced risk was not observed with other types of antidiabetic agents. When considering the duration of antidiabetic medication therapy, current use of metformin for 91-180 and 181-365 days was associated with a 28% (aOR, 0.72; 95% CI 0.58-0.89) and 37% (aOR, 0.63; 95% CI 0.51-0.77) reduced risk of severe COPD exacerbation, respectively. Similarly, 91-180 days of sulfonylureas therapy led to a 28% (aOR, 0.72; 95% CI 0.58-0.90) lower risk, and longer treatments consistently yielded 24-30% lower risks. Current use of thiazolidinediones for more than 181 days yielded an approximately 40% decreased risk. CONCLUSIONS: Duration-dependent beneficial effects of current metformin, sulfonylurea, and thiazolidinedione use on severe COPD exacerbation were observed in patients with COPD and DM.


Asunto(s)
Diabetes Mellitus/tratamiento farmacológico , Hospitalización , Hipoglucemiantes/administración & dosificación , Enfermedad Pulmonar Obstructiva Crónica/terapia , Administración Oral , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Bases de Datos Factuales , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiología , Progresión de la Enfermedad , Femenino , Humanos , Hipoglucemiantes/efectos adversos , Masculino , Metformina/administración & dosificación , Persona de Mediana Edad , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/epidemiología , Medición de Riesgo , Factores de Riesgo , Índice de Severidad de la Enfermedad , Compuestos de Sulfonilurea/administración & dosificación , Taiwán/epidemiología , Tiazolidinedionas/administración & dosificación , Factores de Tiempo
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