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1.
Plant Cell ; 36(5): 1963-1984, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38271284

RESUMEN

Photoperiod is a crucial environmental cue for phenological responses, including growth cessation and winter dormancy in perennial woody plants. Two regulatory modules within the photoperiod pathway explain bud dormancy induction in poplar (Populus spp.): the circadian oscillator LATE ELONGATED HYPOCOTYL 2 (LHY2) and GIGANTEA-like genes (GIs) both regulate the key target for winter dormancy induction FLOWERING LOCUS T2 (FT2). However, modification of LHY2 and GIs cannot completely prevent growth cessation and bud set under short-day (SD) conditions, indicating that additional regulatory modules are likely involved. We identified PtoHY5a, an orthologs of the photomorphogenesis regulatory factor ELONGATED HYPOCOTYL 5 (HY5) in poplar (Populus tomentosa), that directly activates PtoFT2 expression and represses the circadian oscillation of LHY2, indirectly activating PtoFT2 expression. Thus, PtoHY5a suppresses SD-induced growth cessation and bud set. Accordingly, PtoHY5a knockout facilitates dormancy induction. PtoHY5a also inhibits bud-break in poplar by controlling gibberellic acid (GA) levels in apical buds. Additionally, PtoHY5a regulates the photoperiodic control of seasonal growth downstream of phytochrome PHYB2. Thus, PtoHY5a modulates seasonal growth in poplar by regulating the PtoPHYB2-PtoHY5a-PtoFT2 module to determine the onset of winter dormancy, and by fine-tuning GA levels to control bud-break.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Giberelinas , Fotoperiodo , Latencia en las Plantas , Proteínas de Plantas , Populus , Populus/genética , Populus/crecimiento & desarrollo , Populus/metabolismo , Populus/fisiología , Giberelinas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Latencia en las Plantas/genética , Flores/genética , Flores/fisiología , Flores/crecimiento & desarrollo
2.
BMC Plant Biol ; 24(1): 921, 2024 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-39358690

RESUMEN

BACKGROUND: The UDP-glucuronosyltransferase 91D2 (SrUGT91D2) gene is a crucial element in the biosynthetic pathway of steviol glycosides (SGs) and is responsible for creating 1,2-ß-D glucosidic bonds at the C19 and C13 positions. This process plays a vital role in the synthesis of rebaudioside M (RM) and rebaudioside D (RD). The promoter, which regulates gene expression, requires functional analysis to understand gene expression regulation. However, investigations into the function of the promoter of SrUGT91D2 (pSrUGT91D2) have not been reported. RESULTS: The pSrUGT91D2 was isolated from six S. rebaudiana lines, and subsequent multiple sequence comparisons revealed the presence of a 26 bp inDel fragment (pSrUGT91D2-B1188 type) in lines GP, GX, 110, 1114, and B1188 but not in the pSrUGT91D2 of line 023 (pSrUGT91D2-023 type). Bioinformatics analysis revealed a prevalence of significant cis-regulatory elements (CREs) within the promoter sequences, including those responsive to abscisic acid, light, anaerobic conditions, auxin, drought, low temperature, and MeJA. To verify the activity of pSrUGT91D2, the full-length promoter and a series of 5' deletion fragments (P1-P7) and a 3' deletion fragment (P8) from various lines were fused with the reporter ß-glucuronidase (GUS) gene to construct the plant expression vector, pCAMBIA1300-pro∷GUS. The transcriptional activity of these genes was examined in tobacco leaves through transient transformation. GUS tissue staining analysis and enzyme activity assays demonstrated that both the full-length promoter and truncated pSrUGT91D2 were capable of initiating GUS expression in tobacco leaves. Interestingly, P8-pSrUGT91D2-B1188 (containing the inDel segment, 301 bp) exhibited enhanced activity in driving GUS gene expression. Transient expression studies of P8-pSrUGT91D2-B1188 and P8-pSrUGT91D2-023 in response to exogenous hormones (abscisic acid and indole-3-acetic acid) and light indicated the necessity of the inDel region for P8 to exhibit transcriptional activity, as it displayed strong responsiveness to abscisic acid (ABA), indole-3-acetic acid (IAA), and light induction. CONCLUSIONS: These findings contribute to a deeper understanding of the regulatory mechanism of the upstream region of the SrUGT91D2 gene and provide a theoretical basis for future studies on the interaction between CREs of pSrUGT91D2 and related transcription factors.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Reguladores del Crecimiento de las Plantas , Regiones Promotoras Genéticas , Stevia , Estrés Fisiológico , Regiones Promotoras Genéticas/genética , Stevia/genética , Stevia/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Reguladores del Crecimiento de las Plantas/farmacología , Estrés Fisiológico/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Diterpenos de Tipo Kaurano/metabolismo
3.
BMC Infect Dis ; 24(1): 327, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38500029

RESUMEN

BACKGROUND: Ralstonia pickettii is a low virulent, gram-negative bacillus that is rarely associated with human infections and may cause bacteremia. Microbacterium species are gram-positive coryneforms that are generally considered as a contaminant in Gram staining of blood cultures, especially when the time to positivity is longer than 48 h. Both these bacterial species are emerging opportunistic pathogens that may occasionally cause serious infections and even life-threatening health conditions. CASE PRESENTATION: Here, we report the case of a patient with bacteremia caused by both R. pickettii and Microbacterium. We advocate for providers to order rapid antibiotic susceptibility testing, since our patient's suffered two kinds of rare pathogens with the opposite of drug sensitivity results to imipenem. CONCLUSIONS: Our case present a patient suffered septic shock caused by R. pickettii and Microbacterium. Improving the antibiotic management based on the result of antimicrobial susceptibility tests is the key of successful treatment.


Asunto(s)
Bacteriemia , Infecciones por Bacterias Gramnegativas , Ralstonia pickettii , Humanos , Microbacterium , Infecciones por Bacterias Gramnegativas/diagnóstico , Infecciones por Bacterias Gramnegativas/tratamiento farmacológico , Infecciones por Bacterias Gramnegativas/etiología , Antibacterianos/uso terapéutico , Bacteriemia/diagnóstico , Bacteriemia/tratamiento farmacológico , Bacteriemia/complicaciones
4.
BMC Geriatr ; 24(1): 742, 2024 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-39244543

RESUMEN

OBJECTIVE: To analyze the influential factors of frailty in elderly patients with coronary heart disease (CHD), develop a nomogram-based risk prediction model for this population, and validate its predictive performance. METHODS: A total of 592 elderly patients with CHD were conveniently selected and enrolled from 3 tertiary hospitals, 5 secondary hospitals, and 3 community health service centers in China between October 2022 and January 2023. Data collection involved the use of the general information questionnaire, the Frail scale, and the instrumental ability of daily living assessment scale. And the patients were categorized into two groups based on frailty, and χ2 test as well as logistic regression analysis were used to identify and determine the influencing factors of frailty. The nomograph prediction model for elderly patients with CHD was developed using R software (version 4.2.2). The Hosmer-Lemeshow test and the area under the receiver operating characteristic (ROC) curve were employed to assess the predictive performance of the model. Additionally, the Bootstrap resampling method was utilized to validate the model and generate the calibration curve of the prediction model. RESULTS: The prevalence of frailty in elderly patients with CHD was 30.07%. The multiple factor analysis revealed that poor health status (OR = 28.169)/general health status (OR = 18.120), age (OR = 1.046), social activities (OR = 0.673), impaired instrumental ability of daily living (OR = 2.384) were independent risk factors for frailty (all P < 0.05). The area under the ROC curve of the nomograph prediction model was 0.847 (95% CI: 0.809 ~ 0.878, P < 0.001), with a sensitivity of 0.801, and specificity of 0.793; the Hosmer- Lemeshow χ2 value was 12.646 (P = 0.125). The model validation results indicated that the C value of 0.839(95% CI: 0.802 ~ 0.879) and Brier score of 0.139, demonstrating good consistency between predicted and actual values. CONCLUSION: The prevalence of frailty is high among elderly patients with CHD, and it is influenced by various factors such as health status, age, lack of social participation, and impaired ability of daily life. These factors have certain predictive value for identifying frailty early and intervention in elderly patients with CHD.


Asunto(s)
Enfermedad Coronaria , Fragilidad , Evaluación Geriátrica , Humanos , Anciano , Masculino , Femenino , Enfermedad Coronaria/epidemiología , Enfermedad Coronaria/diagnóstico , Fragilidad/epidemiología , Fragilidad/diagnóstico , Medición de Riesgo/métodos , Evaluación Geriátrica/métodos , Anciano de 80 o más Años , Anciano Frágil , China/epidemiología , Nomogramas , Factores de Riesgo , Actividades Cotidianas , Persona de Mediana Edad
5.
World J Microbiol Biotechnol ; 40(3): 101, 2024 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-38366186

RESUMEN

Xenorhabdus, known for its symbiotic relationship with Entomopathogenic nematodes (EPNs), belongs to the Enterobacteriaceae family. This dual-host symbiotic nematode exhibits pathogenic traits, rendering it a promising biocontrol agent against insects. Our prior investigations revealed that Xenorhabdus stockiae HN_xs01, isolated in our laboratory, demonstrates exceptional potential in halting bacterial growth and displaying anti-tumor activity. Subsequently, we separated and purified the supernatant of the HN_xs01 strain and obtained a new compound with significant inhibitory activity on tumor cells, which we named XNAE. Through LC-MS analysis, the mass-to-nucleus ratio of XNAE was determined to be 254.24. Our findings indicated that XNAE exerts a time- and dose-dependent inhibition on B16 and HeLa cells. After 24 h, its IC50 for B16 and HeLa cells was 30.178 µg/mL and 33.015 µg/mL, respectively. Electron microscopy revealed conspicuous damage to subcellular structures, notably mitochondria and the cytoskeleton, resulting in a notable reduction in cell numbers among treated tumor cells. Interestingly, while XNAE exerted a more pronounced inhibitory effect on B16 cells compared to HeLa cells, it showed no discernible impact on HUVEC cells. Treatment of B16 cells with XNAE induced early apoptosis and led to cell cycle arrest in the G2 phase, as evidenced by flow cytometry analysis. The impressive capability of X. stockiae HN_xs01 in synthesizing bioactive secondary metabolites promises to significantly expand the reservoir of natural products. Further exploration to identify the bioactivity of these compounds holds the potential to shed light on their roles in bacteria-host interaction. Overall, these outcomes underscore the promising potential of XNAE as a bioactive compound for tumor treatment.


Asunto(s)
Nematodos , Xenorhabdus , Animales , Humanos , Xenorhabdus/metabolismo , Células HeLa , Nematodos/microbiología , Enterobacteriaceae , Simbiosis
6.
Angew Chem Int Ed Engl ; 63(10): e202318155, 2024 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-38109458

RESUMEN

Real-time monitoring of hydroxyl radical (⋅OH) generation is crucial for both the efficacy and safety of chemodynamic therapy (CDT). Although ⋅OH probe-integrated CDT agents can track ⋅OH production by themselves, they often require complicated synthetic procedures and suffer from self-consumption of ⋅OH. Here, we report the facile fabrication of a self-monitored chemodynamic agent (denoted as Fc-CD-AuNCs) by incorporating ferrocene (Fc) into ß-cyclodextrin (CD)-functionalized gold nanoclusters (AuNCs) via host-guest molecular recognition. The water-soluble CD served not only as a capping agent to protect AuNCs but also as a macrocyclic host to encapsulate and solubilize hydrophobic Fc guest with high Fenton reactivity for in vivo CDT applications. Importantly, the encapsulated Fc inside CD possessed strong electron-donating ability to effectively quench the second near-infrared (NIR-II) fluorescence of AuNCs through photoinduced electron transfer. After internalization of Fc-CD-AuNCs by cancer cells, Fenton reaction between redox-active Fc quencher and endogenous hydrogen peroxide (H2 O2 ) caused Fc oxidation and subsequent NIR-II fluorescence recovery, which was accompanied by the formation of cytotoxic ⋅OH and therefore allowed Fc-CD-AuNCs to in situ self-report ⋅OH generation without undesired ⋅OH consumption. Such a NIR-II fluorescence-monitored CDT enabled the use of renal-clearable Fc-CD-AuNCs for efficient tumor growth inhibition with minimal side effects in vivo.


Asunto(s)
Compuestos Ferrosos , Nanopartículas , Neoplasias , Humanos , Nanomedicina , Metalocenos , Fluorescencia , Oxidación-Reducción , Línea Celular Tumoral , Peróxido de Hidrógeno/química , Nanopartículas/química , Microambiente Tumoral
7.
J Am Chem Soc ; 145(43): 23849-23858, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37861695

RESUMEN

Accelerating proton transfer has been demonstrated as key to boosting water oxidation on semiconductor photoanodes. Herein, we study proton-coupled electron transfer (PCET) of water oxidation on five typical photoanodes [i.e., α-Fe2O3, BiVO4, TiO2, plasmonic Au/TiO2, and nickel-iron oxyhydroxide (Ni1-xFexOOH)-modified silicon (Si)] by combining the rate law analysis of H2O molecules with the H/D kinetic isotope effect (KIE) and operando spectroscopic studies. An unexpected and universal half-order kinetics is observed for the rate law analysis of H2O, referring to a sequential proton-electron transfer pathway, which is the rate-limiting factor that causes the sluggish water oxidation performance. Surface modification of the Ni1-xFexOOH electrocatalyst is observed to break this limitation and exhibits a normal first-order kinetics accompanied by much enhanced H/D KIE values, facilitating the turnover frequency of water oxidation by 1 order of magnitude. It is the first time that Ni1-xFexOOH is found to be a PCET modulator. The rate law analysis illustrates an effective strategy for modulating PCET kinetics of water oxidation on semiconductor surfaces.

8.
BMC Plant Biol ; 23(1): 415, 2023 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-37684590

RESUMEN

As one of the largest plant specific transcription factor families, NAC family members play an important role in plant growth, development and stress resistance. To investigate the function of NAC transcription factors during abiotic stress, as well as during somatic embryogenesis, we identified and characterized the NAC gene family in Liriodendron chinense. We found that most LcNAC members contain more than three exons, with a relatively conserved gene and motif structure, especially at the N-terminus. Interspecies collinearity analysis revealed a closer relationship between the L. chinense NACs and the P. trichocarpa NACs. We analyzed the expression of LcNAC in different tissues and under three abiotic stresses. We found that 12 genes were highly expressed during the ES3 and ES4 stages of somatic embryos, suggesting that they are involved in the development of somatic embryos. 6 LcNAC genes are highly expressed in flower organs. The expression pattern analysis of LcNACs based on transcriptome data and RT-qPCR obtained from L. chinense leaves indicated differential expression responses to drought, cold, and heat stress. Genes in the NAM subfamily expressed differently during abiotic stress, and LcNAC6/18/41/65 might be the key genes in response to abiotic stress. LcNAC6/18/41/65 were cloned and transiently transformed into Liriodendron protoplasts, where LcNAC18/65 was localized in cytoplasm and nucleus, and LcNAC6/41 was localized only in nucleus. Overall, our findings suggest a role of the NAC gene family during environmental stresses in L. chinense. This research provides a basis for further study of NAC genes in Liriodendron chinense.


Asunto(s)
Liriodendron , Acetilcisteína , Núcleo Celular , Citoplasma
9.
Zhongguo Zhong Yao Za Zhi ; 48(19): 5172-5180, 2023 Oct.
Artículo en Zh | MEDLINE | ID: mdl-38114107

RESUMEN

Excessive application of chemical fertilizer has caused many problems in Angelica dahurica var. formosana planting, such as yield decline and quality degradation. In order to promote the green cultivation mode of A. dahurica var. formosana and explore rhizosphere fungus resources, the rhizosphere fungi with nitrogen fixation, phosphorus solubilization, potassium solubilization, iron-producing carrier, and IAA-producing properties were isolated and screened in the rhizosphere of A. dahurica var. formosana from the genuine and non-genuine areas, respectively. The strains were identified comprehensively in light of the morphological characteristics and ITS rDNA sequences, and the growth-promoting effect of the screened strains was verified by pot experiment. The results showed that 37 strains of growth-promoting fungi were isolated and screened from the rhizosphere of A. dahurica var. formosana, mostly belonging to Fusarium. The cultured rhizosphere growth-promoting fungi of A. dahurica var. formosana were more abundant and diverse in the genuine producing areas than in the non-genuine producing areas. Among all strains, Aspergillus niger ZJ-17 had the strongest growth promotion potential. Under the condition of no fertilization outdoors, ZJ-17 inoculation significantly promoted the growth, yield, and accumulation of effective components of A. dahurica var. formosana planted in the soil of genuine and non-genuine producing areas, with yield increases of 73.59% and 37.84%, respectively. To a certain extent, it alleviated the restriction without additional fertilization on the growth of A. dahurica var. formosana. Therefore, A. niger ZJ-17 has great application prospects in increasing yield and quality of A. dahurica var. formosana and reducing fertilizer application and can be actually applied in promoting the growth of A. dahurica var. formosana and producing biofertilizer.


Asunto(s)
Angelica , Fertilizantes , Rizosfera , Angelica/química , Hongos/genética , Fósforo
10.
BMC Plant Biol ; 22(1): 25, 2022 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-35012508

RESUMEN

BACKGROUND: Liriodendron chinense (Lchi) is a tree species within the Magnoliaceae family and is considered a basal angiosperm. The too low or high temperature or soil drought will restrict its growth as the adverse environmental conditions, thus improving L. chinense abiotic tolerance was the key issues to study. WRKYs are a major family of plant transcription factors known to often be involved in biotic and abiotic stress responses. So far, it is still largely unknown if and how the LchiWRKY gene family is tied to regulating L. chinense stress responses. Therefore, studying the involvement of the WRKY gene family in abiotic stress regulation in L. chinense could be very informative in showing how this tree deals with such stressful conditions. RESULTS: In this research, we performed a genome-wide analysis of the Liriodendron chinense (Lchi) WRKY gene family, studying their classification relationships, gene structure, chromosomal locations, gene duplication, cis-element, and response to abiotic stress. The 44 members of the LchiWRKY gene family contain a significant amount of sequence diversity, with their lengths ranging from 525 bp to 40,981 bp. Using classification analysis, we divided the 44 LchiWRKY genes into three phylogenetic groups (I, II, II), with group II then being further divided into five subgroups (IIa, IIb, IIc, IId, IIe). Comparative phylogenetic analysis including the WRKY families from 17 plant species suggested that LchiWRKYs are closely related to the Magnolia Cinnamomum kanehirae WRKY family, and has fewer family members than higher plants. We found the LchiWRKYs to be evenly distributed across 15 chromosomes, with their duplication events suggesting that tandem duplication may have played a major role in LchiWRKY gene expansion model. A Ka/Ks analysis indicated that they mainly underwent purifying selection and distributed in the group IId. Motif analysis showed that LchiWRKYs contained 20 motifs, and different phylogenetic groups contained conserved motif. Gene ontology (GO) analysis showed that LchiWRKYs were mainly enriched in two categories, i.e., biological process and molecular function. Two group IIc members (LchiWRKY10 and LchiWRKY37) contain unique WRKY element sequence variants (WRKYGKK and WRKYGKS). Gene structure analysis showed that most LchiWRKYs possess 3 exons and two different types of introns: the R- and V-type which are both contained within the WRKY domain (WD). Additional promoter cis-element analysis indicated that 12 cis-elements that play different functions in environmental adaptability occur across all LchiWRKY groups. Heat, cold, and drought stress mainly induced the expression of group II and I LchiWRKYs, some of which had undergone gene duplication during evolution, and more than half of which had three exons. LchiWRKY33 mainly responded to cold stress and LchiWRKY25 mainly responded to heat stress, and LchiWRKY18 mainly responded to drought stress, which was almost 4-fold highly expressed, while 5 LchiWRKYs (LchiWRKY5, LchiWRKY23, LchiWRKY14, LchiWRKY27, and LchiWRKY36) responded equally three stresses with more than 6-fold expression. Subcellular localization analysis showed that all LchiWRKYs were localized in the nucleus, and subcellular localization experiments of LchiWRKY18 and 36 also showed that these two transcription factors were expressed in the nucleus. CONCLUSIONS: This study shows that in Liriodendron chinense, several WRKY genes like LchiWRKY33, LchiWRKY25, and LchiWRKY18, respond to cold or heat or drought stress, suggesting that they may indeed play a role in regulating the tree's response to such conditions. This information will prove a pivotal role in directing further studies on the function of the LchiWRKY gene family in abiotic stress response and provides a theoretical basis for popularizing afforestation in different regions of China.


Asunto(s)
Aclimatación/genética , Respuesta al Choque por Frío/genética , Deshidratación/genética , Sequías , Estudio de Asociación del Genoma Completo , Respuesta al Choque Térmico/genética , Liriodendron/genética , China , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Familia de Multigenes , Filogenia
11.
Physiol Plant ; 174(4): e13751, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36004736

RESUMEN

Finding the adequate balance between wood formation and abiotic stress resistance is still an important challenge for industrial woody crops. In this study, PeNAC122, a member of the NAC transcription factor (TF) family highly expressed in xylem, was cloned from Populus euphratica. Tissue expression and ß-glucuronidase (GUS) staining showed that PeNAC122 was exclusively expressed in phloem fiber and secondary xylem of stems. Subcellular and yeast transactivation assays confirmed that PeNAC122 protein existed in the nucleus and did not have transcriptional activation and inhibitory activity. Overexpression of PeNAC122 poplar lines exhibited reduced plant height, thickened xylem, and accumulated lignin content in stems, and also upregulates the expression of secondary cell wall biosynthetic genes. Moreover, overexpression of PeNAC122 lines displayed more tolerance to PEG6000-induced osmotic stress, with stronger photosynthetic performance, higher antioxidant enzyme activity, and less accumulation of reactive oxygen species in leaves, and higher expression levels of stress response genes DREB2A, RD29, and NCED3. These results indicate that PeNAC122 plays a crucial role in wood formation and abiotic stress tolerance, which, in addition to potential use in improving wood quality, provides further insight into the role of NAC family TFs in balancing wood development and abiotic stress resistance.


Asunto(s)
Populus , Pared Celular/metabolismo , Regulación de la Expresión Génica de las Plantas/genética , Presión Osmótica , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismo , Populus/metabolismo , Madera/genética , Madera/metabolismo , Xilema/genética
12.
Appl Microbiol Biotechnol ; 106(23): 7857-7866, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36326838

RESUMEN

Xenorhabdus can produce a large number of secondary metabolites with insecticidal, bacteriostatic, and antitumor activities. Efficient gene editing tools will undoubtedly facilitate the functional genomics research and bioprospecting in Xenorhabdus. In this study, BlastP analysis using the amino acid sequences of Redαß or RecET recombinases as queries resulted in the identification of an operon (XBJ1_operon 0213) containing RecET-like recombinases encoding genes from the genome of Xenorhabdus bovienii strain SS-2004. Three proteins encoded by this operon was indispensable for full activity of recombineering, namely XBJ1-1173 (RecE-like protein), XBJ1-1172 (RecT-like protein), and XBJ1-1171 (single-strand annealing protein). Using this newly developed recombineering system, a gene cluster responsible for biosynthesis of a novel secondary metabolite (Min16) was identified from X. stockiae HN_xs01 strain. Min16 which exhibited antibacterial and cytotoxic activities was determined to be a cyclopeptide composed of Acyl-Phe-Thr-Phe-Pro-Pro-Leu-Val by using high-resolution mass spectrometry and nuclear magnetic resonance analysis, and was designated as changshamycin. This host-specific recombineering system was proven to be effective for gene editing in Xenorhabdus, allowing for efficient discovery of novel natural products with attractive bioactivities. KEY POINTS: • Screening and identification of efficient gene editing tools from Xenorhabdus • Optimization of the Xenorhabdus electroporation parameters • Discovery of a novel cyclopeptide compound with multiple biological activities.


Asunto(s)
Productos Biológicos , Xenorhabdus , Xenorhabdus/genética , Recombinasas/genética , Recombinasas/metabolismo , Productos Biológicos/metabolismo , Operón , Péptidos Cíclicos/metabolismo
13.
BMC Oral Health ; 22(1): 481, 2022 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-36357898

RESUMEN

The environment of healthcare institutes (HCIs) potentially affects the internal microecology of medical workers, which is reflected not only in the well-studied gut microbiome but also in the more susceptible oral microbiome. We conducted a prospective cross-sectional cohort study in four hospital departments in Central China. Oropharyngeal swabs from 65 healthcare workers were collected and analyzed using 16S rRNA gene amplicon sequencing. The oral microbiome of healthcare workers exhibited prominent deviations in diversity, microbial structure, and predicted function. The coronary care unit (CCU) samples exhibited robust features and stability, with significantly higher abundances of genera such as Haemophilus, Fusobacterium, and Streptococcus, and a lower abundance of Prevotella. Functional prediction analysis showed that vitamin, nucleotide, and amino acid metabolisms were significantly different among the four departments. The CCU group was at a potential risk of developing periodontal disease owing to the increased abundance of F. nucleatum. Additionally, oral microbial diversification of healthcare workers was related to seniority. We described the oral microbiome profile of healthcare workers in different clinical scenarios and demonstrated that community diversity, structure, and potential functions differed markedly among departments. Intense modulation of the oral microbiome of healthcare workers occurs because of their original departments, especially in the CCU.


Asunto(s)
Bacterias , Microbiota , Humanos , ARN Ribosómico 16S/genética , Estudios Transversales , Bacterias/genética , Estudios Prospectivos , Personal de Salud
14.
Angew Chem Int Ed Engl ; 61(50): e202214580, 2022 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-36283956

RESUMEN

The sluggish H2 O oxidation kinetics on photoanodes severely obstructs the overall solar-to-energy efficiency of photoelectrochemical (PEC) cells. Herein, we find a 10 to 55-fold increase of photocurrent by conducting ammonia oxidation reaction (AOR) on hematite (α-Fe2 O3 ) photoanodes under near-neutral pH (9-11) and moderate applied potentials (1.0-1.4 VRHE ) compared to H2 O oxidation. By rate law analysis and operando spectroscopic studies, we confirm the non-radical nucleophilic attack of NH3 molecules on high-valent surface Fe-O species (e.g., FeIV =O) and Fe-N species that produces NOx - and N2 , respectively, which overwhelms the nucleophilic attack of H2 O on surface FeIV =O and contributes to a high Faradaic efficiency of above 80 % for AOR. This work reveals a novel non-radical nucleophilic attack strategy, which is significantly different from the conventional indirect radical-mediated AOR mechanism, for the rational design of high-performance AOR photoelectrocatalysts.

15.
Zhongguo Dang Dai Er Ke Za Zhi ; 24(9): 1036-1041, 2022.
Artículo en Zh | MEDLINE | ID: mdl-36111723

RESUMEN

OBJECTIVES: To study the clinical features of children with rhabdomyosarcoma (RMS) and the influencing factors for prognosis. METHODS: A retrospective analysis was performed on the clinical and follow-up data of 20 children with RMS who were admitted to the Department of Pediatric Hematology, Xiangya Hospital of Central South University, from June 2014 to September 2020. RESULTS: The most common clinical symptoms of the 20 children with RMS at the first visit were painless mass (13/20, 65%), exophthalmos (4/20, 20%), and abdominal pain (3/20, 15%). According to the staging criteria of Intergroup Rhabdomyosarcoma Study Group (IRSG), there was 1 child (5%) with stage I RMS, 4 (20%) with stage II RMS, 9 (45%) with stage III RMS, and 6 (30%) with stage IV RMS. The median follow-up time was 19 months for the 20 children (range: 3-93 months), with a 2-year overall survival (OS) rate of 79.5% (95%CI: 20.1-24.3) and a 2-year event-free survival (EFS) rate of 72.0% (95%CI: 19.5-23.9). Pleomorphic RMS was associated with the reduced 2-year OS rate (P<0.05), and distant metastasis, IRSG stage IV RMS, and high-risk RMS were associated with the reduced 2-year EFS rate (P<0.05). CONCLUSIONS: RMS has no specific clinical symptoms at the first visit, with painless mass as the most common symptom. Distant metastasis, IRSG stage, and risk degree may be associated with the prognosis of children with RMS.


Asunto(s)
Rabdomiosarcoma Embrionario , Rabdomiosarcoma , Niño , Humanos , Pronóstico , Estudios Retrospectivos , Rabdomiosarcoma/diagnóstico , Rabdomiosarcoma/terapia , Tasa de Supervivencia
16.
Brain Behav Immun ; 87: 890-897, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-31931152

RESUMEN

Parkinson's disease (PD) is one of the most significant medical and social burdens of our time. The prevalence of PD increases with age and the number of individuals diagnosed with PD is expected to double from 6.9 million in 2015 to 14.2 million in 2040. To date, no drugs can stop the ongoing neurodegeneration caused by PD due to its unclear and complex pathogenic mechanisms. It has been wildly recognized that both gut microbiota and neuro-immunity are involved in the pathology of PD. In this review, we intend to provide a comprehensive overview of current knowledge on how gut microbiota involved in immune-driven pathogenesis of PD, and its potential as a new target of dietary and/or therapeutic interventions for PD.


Asunto(s)
Microbioma Gastrointestinal , Enfermedad de Parkinson , Humanos
18.
Adv Sci (Weinh) ; : e2408767, 2024 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-39447122

RESUMEN

Semiconductor-based photoelectrochemical (PEC) organic transformations usually show radical characteristics, in which the reaction selectivity is often difficult to precisely control due to the nonselectivity of radicals. Accordingly, several simple organic reactions (e.g., oxidations of alcohols, aldehydes, and other small molecules) have been widely studied, while more complicated processes like C─C coupling remain challenging. Herein, a synergistic heterogeneous/homogeneous PEC strategy is developed to achieve a controllable radical-induced C─C coupling reaction mediated by the copper-coordination effect at the semiconductor/electrolyte interfaces, which additionally exerts a significant impact on the product regioselectivity. Through experimental studies and theoretical simulations, this study reveals that the copper-chloride complex effectively regulates the formation of chloride radicals, a typical hydrogen atom transfer agent, on semiconductor surfaces and stabilizes the heterogeneous interfaces by suppressing the radical-induced surface passivation. Taking the Minisci reaction (the coupling between 2-phenylquinoline and cyclohexane) as a model, the yield of the target C─C coupling product reaches up to 90% on TiO2 photoanodes with a selectivity of 95% and long-term stability over 100 h. Moreover, such a strategy exhibits a broad scope and can be used for the functionalization of various heteroaromatic hydrocarbons.

19.
Front Cell Infect Microbiol ; 14: 1347345, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38828262

RESUMEN

Background: To date, more than 770 million individuals have become coronavirus disease 2019 (COVID-19) convalescents worldwide. Emerging evidence highlights the influence of COVID-19 on the oral microbiome during both acute and convalescent disease phases. Front-line healthcare workers are at an elevated risk of exposure to viral infections, and the effects of COVID-19 on their oral microbiome remain relatively unexplored. Methods: Oropharyngeal swab specimens, collected one month after a negative COVID-19 test from a cohort comprising 55 healthcare workers, underwent 16S rRNA sequencing. We conducted a comparative analysis between this post-COVID-19 cohort and the pre-infection dataset from the same participants. Community composition analysis, indicator species analysis, alpha diversity assessment, beta diversity exploration, and functional prediction were evaluated. Results: The Shannon and Simpson indexes of the oral microbial community declined significantly in the post-COVID-19 group when compared with the pre-infection cohort. Moreover, there was clear intergroup clustering between the two groups. In the post-COVID-19 group, the phylum Firmicutes showed a significant increase. Further, there were clear differences in relative abundance of several bacterial genera in contrast with the pre-infection group, including Streptococcus, Gemella, Granulicatella, Capnocytophaga, Leptotrichia, Fusobacterium, and Prevotella. We identified Gemella enrichment in the post-COVID-19 group, potentially serving as a recovery period performance indicator. Functional prediction revealed lipopolysaccharide biosynthesis downregulation in the post-COVID-19 group, an outcome with host inflammatory response modulation and innate defence mechanism implications. Conclusion: During the recovery phase of COVID-19, the oral microbiome diversity of front-line healthcare workers failed to fully return to its pre-infection state. Despite the negative COVID-19 test result one month later, notable disparities persisted in the composition and functional attributes of the oral microbiota.


Asunto(s)
Bacterias , COVID-19 , Personal de Salud , Microbiota , Orofaringe , ARN Ribosómico 16S , SARS-CoV-2 , Humanos , COVID-19/microbiología , Orofaringe/microbiología , Orofaringe/virología , SARS-CoV-2/aislamiento & purificación , SARS-CoV-2/genética , Adulto , ARN Ribosómico 16S/genética , Masculino , Femenino , Bacterias/clasificación , Bacterias/aislamiento & purificación , Bacterias/genética , Persona de Mediana Edad , Estudios de Cohortes
20.
Natl Sci Rev ; 11(4): nwae053, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38666092

RESUMEN

The water oxidation half-reaction at anodes is always considered the rate-limiting step of overall water splitting (OWS), but the actual bias distribution between photoanodes and cathodes of photoelectrochemical (PEC) OWS cells has not been investigated systematically. In this work, we find that, for PEC cells consisting of photoanodes (nickel-modified n-Si [Ni/n-Si] and α-Fe2O3) with low photovoltage (Vph < 1 V), a large portion of applied bias is exerted on the Pt cathode for satisfying the hydrogen evolution thermodynamics, showing a thermodynamics-controlled characteristic. In contrast, for photoanodes (TiO2 and BiVO4) with Vph > 1 V, the bias required for cathode activation can be significantly reduced, exhibiting a kinetics-controlled characteristic. Further investigations show that the bias distribution can be regulated by tuning the electrolyte pH and using alternative half-reaction couplings. Accordingly, a volcano plot is presented for the rational design of the overall reactions and unbiased PEC cells. Motivated by this, an unbiased PEC cell consisting of a simple Ni/n-Si photoanode and Pt cathode is assembled, delivering a photocurrent density of 5.3 ± 0.2 mA cm-2.

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