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1.
J Transl Med ; 22(1): 472, 2024 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-38762511

RESUMEN

BACKGROUND: Vessels encapsulating tumor clusters (VETC) is a newly described vascular pattern that is distinct from microvascular invasion (MVI) in patients with hepatocellular carcinoma (HCC). Despite its importance, the current pathological diagnosis report does not include information on VETC and hepatic plates (HP). We aimed to evaluate the prognostic value of integrating VETC and HP (VETC-HP model) in the assessment of HCC. METHODS: A total of 1255 HCC patients who underwent radical surgery were classified into training (879 patients) and validation (376 patients) cohorts. Additionally, 37 patients treated with lenvatinib were studied, included 31 patients in high-risk group and 6 patients in low-risk group. Least absolute shrinkage and selection operator (LASSO) regression analysis was used to establish a prognostic model for the training set. Harrell's concordance index (C-index), time-dependent receiver operating characteristics curve (tdROC), and decision curve analysis were utilized to evaluate our model's performance by comparing it to traditional tumor node metastasis (TNM) staging for individualized prognosis. RESULTS: A prognostic model, VETC-HP model, based on risk scores for overall survival (OS) was established. The VETC-HP model demonstrated robust performance, with area under the curve (AUC) values of 0.832 and 0.780 for predicting 3- and 5-year OS in the training cohort, and 0.805 and 0.750 in the validation cohort, respectively. The model showed superior prediction accuracy and discrimination power compared to TNM staging, with C-index values of 0.753 and 0.672 for OS and disease-free survival (DFS) in the training cohort, and 0.728 and 0.615 in the validation cohort, respectively, compared to 0.626 and 0.573 for TNM staging in the training cohort, and 0.629 and 0.511 in the validation cohort. Thus, VETC-HP model had higher C-index than TNM stage system(p < 0.01).Furthermore, in the high-risk group, lenvatinib alone appeared to offer less clinical benefit but better disease-free survival time. CONCLUSIONS: The VETC-HP model enhances DFS and OS prediction in HCC compared to traditional TNM staging systems. This model enables personalized temporal survival estimation, potentially improving clinical decision-making in surveillance management and treatment strategies.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/mortalidad , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/mortalidad , Masculino , Femenino , Persona de Mediana Edad , Pronóstico , Curva ROC , Anciano , Análisis de Supervivencia , Estimación de Kaplan-Meier , Reproducibilidad de los Resultados , Quinolinas/uso terapéutico , Compuestos de Fenilurea
2.
BMC Genomics ; 24(1): 291, 2023 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-37254055

RESUMEN

BACKGROUND: Hong Kong catfish (Clarias fuscus) is an ecologically and economically important species that is widely distributed in freshwater regions of southern China. Hong Kong catfish has significant sexual growth dimorphism. The genome assembly of the Hong Kong catfish would facilitate study of the sex determination and evolution mechanism of the species. RESULTS: The first high-quality chromosome-level genome of the Hong Kong catfish was constructed. The total genome was 933.4 Mb, with 416 contigs and a contig N50 length of 8.52 Mb. Using high-throughput chromosome conformation capture (Hi-C) data, the genome assembly was divided into 28 chromosomes with a scaffold N50 length of 36.68 Mb. A total of 23,345 protein-coding genes were predicted in the genome, and 94.28% of the genes were functionally annotated in public databases. Phylogenetic analysis indicated that C. fuscus and Clarias magur diverged approximately 63.7 million years ago. The comparative genome results showed that a total of 60 unique, 353 expanded and 851 contracted gene families were identified in Hong Kong catfish. A sex-linked quantitative trait locus identified in a previous study was located in a sex-determining region of 30.26 Mb (0.02 to 30.28 Mb) on chromosome 13 (Chr13), the predicted Y chromosome. This QTL region contained 785 genes, of which 18 were identified as sex-related genes. CONCLUSIONS: This study is the first to report the chromosome-level genome assembly of Hong Kong catfish. The study provides an excellent genetic resource that will facilitate future studies of sex determination mechanisms and evolution in fish.


Asunto(s)
Bagres , Cromosomas , Animales , Filogenia , Hong Kong , Genoma , Bagres/genética , Cromosoma Y
3.
Antimicrob Agents Chemother ; 67(11): e0081223, 2023 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-37877694

RESUMEN

Type II toxin-antitoxin systems are highly prevalent in bacterial genomes and play crucial roles in the general stress response. Previously, we demonstrated that the type II antitoxin PfMqsA regulates biofilm formation through the global regulator AgtR in Pseudomonas fluorescens. Here, we found that both the C-terminal DNA-binding domain of PfMqsA and AgtR are involved in bacterial antibiotic susceptibility. Electrophoretic mobility shift assay (EMSA) analyses revealed that AgtR, rather than PfMqsA, binds to the intergenic region of emhABC-emhR, in which emhABC encodes an resistance-nodulation-cell division efflux pump and emhR encodes a repressor. Through quantitative real-time reverse-transcription PCR and EMSA analysis, we showed that AgtR directly activates the expression of the emhR by binding to the DNA motif [5´-CTAAGAAATATACTTAC-3´], leading to repression of the emhABC. Furthermore, we demonstrated that PfMqsA modulates the expression of EmhABC and EmhR. These findings enhance our understanding of the mechanism by which antitoxin PfMqsA contributes to antibiotic susceptibility.


Asunto(s)
Antitoxinas , Pseudomonas fluorescens , Pseudomonas fluorescens/genética , Antibacterianos/farmacología , Antibacterianos/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo
4.
Inorg Chem ; 62(35): 14422-14430, 2023 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-37607342

RESUMEN

Metal ion-doped zero-dimensional halide perovskites provide good platforms to generate broadband emission and explore the fundamental dynamics of emission regulations. Recently, Sb3+-doped zero-dimensional halide perovskites have attracted considerable attention for the high quantum yield of yellow emission; however, the triplet state recombination is activated and the singlet state emission is usually absent. Herein, we fabricate an Sb3+-doped zero-dimensional [(CH3)4N]2SnCl6 perovskite that can induce singlet and triplet emission. Density functional theory calculation shows that there are some overlaps between the highest occupied molecular orbitals and the lowest unoccupied molecular orbitals, which may induce a large energy separation between the lowest excited triplet states (T1) and the lowest excited singlet states (S1) [ΔE(S1 - T1)], impeding all the carriers' transfer from the singlet state to the triplet state. As a result, the reserved singlet emission together with the triplet emission can be regulated by excitation wavelength in situ. In addition, different Bi3+ ratios are co-doped into Sb3+@[(CH3)4N]2SnCl6, resulting in a photoluminescence ex situ regulation. Single-phase white light LED and optical anti-counterfeiting are developed further.

5.
Curr Microbiol ; 80(5): 171, 2023 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-37024713

RESUMEN

Dengue remains a public health issue worldwide. Similar to chronic infectious diseases, stimulation of cytokine production is not enough to drive immune effector cells for effective virus clearance. One possible mechanism is the virus induces a large number of negative stimulatory cytokines inhibiting immune response. Interleukin 37 (IL-37) plays a crucial regulatory role in infection and immunity, inhibits innate and adaptive immunity as an anti-inflammatory cytokine by inhibiting proinflammatory mediators and pathways. To date, there are few studies reporting correlations between dengue fever (DF) and IL-37. In this study we found that the serum IL-37b and IL-37b-producing monocytes in patients were significantly increased in DF patients. A majority of the IL-37b produced by DF patients was produced by monocytes, not lymphocytes. Increased levels of IL-6, IL-10, and IFN-α were also found in DF patients. However, we failed to detect IL-1ß, IL-17A and TNF-α in plasma, because of off-target. In our study, there was no relation between IL-6, IL-10, and IFN-α expressions and IL-37b in serum (P > 0.05). The IL-37b-producing monocytes were negatively correlated with the level of IFN-α in serum and platelet count, and positively correlated with lymphocytes percentage (P < 0.05, respectively). Additionally, serum DENV nonstructural protein 1 levels were positively correlated with monocytes percentages (P < 0.05). Our data represents findings for IL-37b expression and its potential mechanisms in DF patients' immune response.


Asunto(s)
Virus del Dengue , Dengue , Humanos , Interleucina-10 , Virus del Dengue/fisiología , Interleucina-6 , Carga Viral , Citocinas
6.
Genomics ; 113(3): 910-918, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33600945

RESUMEN

Weeds are the biggest threat to cropping system sustainability in wheat. Metribuzin is a versatile herbicide for broad-spectrum weed management. Understanding key genes, mechanisms and functional markers are essential to develop higher metribuzin tolerant wheats. We identified Chuan Mai 25 (tolerant) and Ritchie (susceptible) as contrasting genotypes to metribuzin stress through dose-response analyses. Transcriptome sequencing using NovaSeq 6000 RNA-Seq platform identified a total of 77,443 genes; 59,915 known genes and 17,528 novel genes. The functional enrichment analysis at 0 h, 24 h and 60 h herbicide exposure revealed that endogenous increase of metabolic enzymes, light-harvesting chlorophyll proteins, PSII stability factor HCF136 and glucose metabolism conferred metribuzin tolerance. The validation of DEGs using RT-qPCR and QTL mapping confirmed their responsiveness to metribuzin. Transcription factors MYB, AP2-EREBP, ABI3VP1, bHLH, NAC are significantly expressed during metribuzin stress. Transcripts with significant enrichments revealed 114 SSRs for genomic selection. The master regulators provide promising avenues for enhancing metribuzin tolerance.


Asunto(s)
Pan , Triticum , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Transcriptoma , Triazinas/metabolismo , Triticum/genética , Triticum/metabolismo
7.
J Med Virol ; 93(2): 1057-1069, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32761898

RESUMEN

To provide a comprehensive and systematic analysis of demographic characteristics, clinical symptoms, laboratory findings, and imaging features of coronavirus disease 2019 (COVID-19) in pediatric patients. A meta-analysis was carried out to identify studies on COVID-19 from 25 December 2019 to 30 April 2020. A total of 48 studies with 5829 pediatric patients were included. Children of all ages were at risk for COVID-19. The main illness classification ranged as: 20% (95% confidence interval [CI]: 14%-26%; I2 = 91.4%) asymptomatic, 33% (95% CI: 23%-43%; I2 = 95.6%) mild and 51% (95% CI: 42%-61%; I2 = 93.4%) moderate. The typical clinical manifestations were fever 51% (95% CI: 45%-57%; I2 = 78.9%) and cough 41% (95% CI: 35%-47%, I2 = 81.0%). The common laboratory findings were normal white blood cell 69% (95% CI: 64%-75%; I2 = 58.5%), lymphopenia 16% (95% CI: 11%-21%; I2 = 76.9%) and elevated creatine-kinase MB 37% (95% CI: 25%-48%; I2 = 59.0%). The frequent imaging features were normal images 41% (95% CI: 30%-52%; I2 = 93.4%) and ground-glass opacity 36% (95% CI: 25%-47%; I2 = 92.9%). Among children under 1 year old, critical cases account for 14% (95% CI: 13%-34%; I2 = 37.3%) that should be of concern. In addition, vomiting occurred in 33% (95% CI: 18%-67%; I2 = 0.0%) cases that may also need attention. Pediatric patients with COVID-19 may experience milder illness with atypical clinical manifestations and rare lymphopenia. High incidence of critical illness and vomiting symptoms reward attention in children under 1 year old.


Asunto(s)
COVID-19/fisiopatología , Adolescente , COVID-19/diagnóstico , Prueba de Ácido Nucleico para COVID-19 , Prueba Serológica para COVID-19 , Niño , Preescolar , Tos/virología , Femenino , Fiebre/virología , Humanos , Lactante , Recién Nacido , Masculino
8.
BMC Cancer ; 21(1): 332, 2021 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-33789601

RESUMEN

BACKGROUND: Small cell neuroendocrine carcinoma of the uterine cervix (SCNEC) is a rare cancer involving the human papilloma virus (HPV), and has few available treatments. The present work aimed to assess the feasibility of SOX2 and HPV statuses as predictive indicators of SCNEC prognosis. METHODS: The associations of SOX2 and/or high-risk (HR)-HPV RNA in situ hybridization (RISH) levels with clinicopathological characteristics and prognostic outcomes for 88 neuroendocrine carcinoma (NEC) cases were analyzed. RESULTS: Among these patients with SCNEC, SOX2, P16INK4A and HR-HPV RISH expression and SOX2/HR-HPV RISH co-expression were detected in 68(77.3%), 76(86.4%), 73(83.0%), and 48(54.5%), respectively. SOX2-positive and HR-HPV RISH-positive SCNEC cases were associated with poorer overall survival (OS, P = 0.0170, P = 0.0451) and disease-free survival (DFS, P = 0.0334, P = 0.0309) compared with those expressing low SOX2 and negative HR-HPV RISH. Alternatively, univariate analysis revealed that SOX2 and HR-HPV RISH expression, either separately or in combination, predicted the poor prognosis of SCNEC patients. Multivariate analysis revealed that the co-expression of SOX2 with HR-HPV RISH may be an independent factor of OS [hazard ratio = 3.597; 95% confidence interval (CI): 1.085-11.928; P = 0.036] and DFS [hazard ratio = 2.880; 95% CI: 1.199-6.919; P = 0.018] prediction in SCNEC. CONCLUSIONS: Overall, the results of the present study suggest that the co-expression of SOX2 with HR-HPV RISH in SCNEC may represent a specific subgroup exhibiting remarkably poorer prognostic outcomes compared with the expression of any one marker alone.


Asunto(s)
Carcinoma Neuroendocrino/metabolismo , Carcinoma Neuroendocrino/virología , Carcinoma de Células Pequeñas/genética , Papillomaviridae/aislamiento & purificación , Infecciones por Papillomavirus/metabolismo , Factores de Transcripción SOXB1/biosíntesis , Neoplasias del Cuello Uterino/metabolismo , Neoplasias del Cuello Uterino/virología , Adulto , Carcinoma Neuroendocrino/genética , Carcinoma Neuroendocrino/patología , Carcinoma de Células Pequeñas/patología , Femenino , Humanos , Hibridación in Situ , Persona de Mediana Edad , Estadificación de Neoplasias , Nomogramas , Papillomaviridae/genética , Infecciones por Papillomavirus/genética , Infecciones por Papillomavirus/patología , Infecciones por Papillomavirus/virología , Pronóstico , ARN Viral/genética , Estudios Retrospectivos , Factores de Transcripción SOXB1/metabolismo , Neoplasias del Cuello Uterino/genética , Neoplasias del Cuello Uterino/patología
9.
Gynecol Oncol ; 162(3): 797-803, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34119365

RESUMEN

OBJECTIVE: Borderline ovarian tumors (BOTs) account for about 15% of all epithelial tumors of the ovary, and around 75% of patients are diagnosed in early stages. Although many of these patients have lymph node involvement (LNI), whether LNI decreases their survival is controversial, raising the question of whether lymphadenectomy should be performed. We conducted a systematic review and meta-analysis of these questions. METHODS: We searched articles related to LNI and lymphadenectomy in patients with BOTs in PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials. Data on rate of LNI, recurrence and survival were pooled and meta-analyzed using a random-effects model. Heterogeneity was evaluated using the I2 test. RESULTS: A total of 25 studies with 12,503 patients were meta-analyzed. The overall pooled rate of LNI was 10% [95% confidence interval (CI) 0.07-0.13]. LNI was associated with a higher risk of recurrence [odds ratio (OR) 2.23, 95% CI 1.13-4.40]. However, LNI did not significantly affect cause-specific survival [hazard ratio (HR) 1.73, 95% CI 0.99-3.02] or disease-free survival (HR 1.48, 95% CI 0.56-3.92). Similarly, lymphadenectomy did not significantly affect risk of recurrence (OR 0.91, 95% CI 0.57-1.46), overall survival (HR 0.90, 95% CI 0.58-1.40), disease-free survival (HR 0.95, 95% CI 0.61-1.50) or progression-free survival (HR 0.60, 95% CI 0.24-1.49). CONCLUSIONS: LNI appears to increase risk of recurrence in BOT patients, but neither it nor lymphadenectomy appears to influence prognosis. Therefore, lymphadenectomy should be considered only for certain BOT patients, such as those with suspected LNI based on imaging or surgical exploration.


Asunto(s)
Carcinoma Epitelial de Ovario/cirugía , Escisión del Ganglio Linfático/efectos adversos , Neoplasias Ováricas/cirugía , Carcinoma Epitelial de Ovario/mortalidad , Femenino , Humanos , Metástasis Linfática , Neoplasias Ováricas/mortalidad
10.
Fish Physiol Biochem ; 47(1): 93-108, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33215297

RESUMEN

Gonadotropin-inhibitory hormone (GnIH) plays a critical role in regulating gonadotropin-releasing hormone (GnRH), gonadotropin hormone (GtH), and steroidogenesis. The Lpxrfa (the piscine ortholog of GnIH) system has been found to regulate fish reproduction. To gain insight into the role of Lpxrfa in the regulation of spotted scat (Scatophagus argus) reproduction, spotted scat Lpxrfa (ssLpxrfa), and its receptor (ssLpxrfa-r) were cloned and analyzed. Tissue distribution and expression patterns at the hypothalamo-pituitary-gonadal axis (HPG axis) of sslpxrfa and sslpxrfa-r mRNA were also investigated during gonadal development of spotted scat. The open reading frame (ORF) of the sslpxrfa was 606 bp encoding 201 amino acids and includes a putative signal peptide and two mature ssLpxrfa peptides with LPXRFamide motif at their C-terminus. The sslpxrfa-r ORF was 1449 bp encoding 482 amino acids and contracted a seven-hydrophobic transmembrane (TM) domain structure. The tissue distribution showe d that the sslpxrfa was highly expressed in hypothalami, gill, and the gonads. In addition, sslpxrfa-r was highly expressed in hypothalami, pituitaries, and the gonads. Quantitative real-time polymerase chain reaction (qPCR) revealed that sslpxrfa had the highest expression in the hypothalami and pituitaries, and the lowest expression in the gonads in stage V. During gonadal development, the expression of sslpxrfa-r was gradually increased in the hypothalami but reduced in the gonads. However, no obvious trend was observed in the pituitaries. The expression of sslpxrfa and sslpxrfa-r decreased significantly after injection with 17ß-estradiol (E2). However, the expression of both sslpxrfa and sslpxrfa-r was not changed after injection with 17α-methyltestosterone(17α-MT) in the hypothalami. In addition, no changes were observed in the expression of fshß and lhß in the pituitaries after injecting ssLpxrfa-1. However, ssLpxrfa-2 could downregulate the expression of sbgnrh and fshß in the hypothalami and pituitaries, respectively. Taken together, these findings suggested that ssLpxrfa may participate in E2 feedback in reproduction and regulate the reproductive axis of spotted scat.


Asunto(s)
Proteínas de Peces/genética , Peces/genética , Neuropéptidos/genética , Receptores de Neuropéptido/genética , Reproducción/genética , Secuencia de Aminoácidos , Animales , Estradiol/farmacología , Femenino , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Gónadas/metabolismo , Sistema Hipotálamo-Hipofisario , Hipotálamo/metabolismo , Masculino , Metiltestosterona/farmacología , Filogenia , Hipófisis/metabolismo
11.
J Med Virol ; 92(9): 1501-1510, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32418216

RESUMEN

There is a current outbreak of coronavirus disease 2019 (COVID-19), with a global spread. With the rapid increase in the number of infections, an increase is observed in the number of children with COVID-19. Most research findings are regarding adult cases, which are not always transferrable to children. Evidence-based studies are still expected to formulate clinical decisions for pediatric patients. In this review, we included 2597 pediatric patients that reported recently and evaluated the demographic, clinical, laboratory, and imaging features of children with COVID-19. We found that even lymphopenia was the most common lab finding in adults; it infrequently occurred in children (9.8%). Moreover, elevated creatine kinase MB isoenzyme was much more commonly observed in children (27.0%) than that in adults, suggesting that heart injury would be more likely to occur in pediatric patients. Our analysis may contribute to determine the spectrum of disease in children and to develop strategies to control the disease transmission.


Asunto(s)
COVID-19/diagnóstico , COVID-19/fisiopatología , Niño , Adolescente , Prueba de Ácido Nucleico para COVID-19 , Enfermedades Cardiovasculares/virología , Preescolar , Forma MB de la Creatina-Quinasa/sangre , Femenino , Humanos , Lactante , Masculino , Pediatría , Tomografía Computarizada por Rayos X , Tratamiento Farmacológico de COVID-19
12.
BMC Med Imaging ; 20(1): 84, 2020 07 23.
Artículo en Inglés | MEDLINE | ID: mdl-32703209

RESUMEN

BACKGROUND: The aim of this was to analyze 4 chest CT imaging features of patients with coronavirus disease 2019 (COVID-19) in Shenzhen, China so as to improve the diagnosis of COVID-19. METHODS: Chest CT of 34 patients with COVID-19 confirmed by the nucleic acid test (NAT) were retrospectively analyzed. Analyses were performed to investigate the pathological basis of four imaging features("feather sign","dandelion sign","pomegranate sign", and "rime sign") and to summarize the follow-up results. RESULTS: There were 22 patients (65.2%) with typical "feather sign"and 18 (52.9%) with "dandelion sign", while few patients had "pomegranate sign" and "rime sign". The "feather sign" and "dandelion sign" were composed of stripe or round ground-glass opacity (GGO), thickened blood vessels, and small-thickened interlobular septa. The "pomegranate sign" was characterized as follows: the increased range of GGO, the significant thickening of the interlobular septum, complicated with a small amount of punctate alveolar hemorrhage. The "rime sign" was characterized by numerous alveolar edemas. Microscopically, the wall thickening, small vascular proliferation, luminal stenosis, and occlusion, accompanied by interstitial infiltration of inflammatory cells, as well as numerous pulmonary interstitial fibrosis and partial hyaline degeneration were observed. Repeated chest CT revealed the mediastinal lymphadenectasis in one patient. Re-examination of the NAT showed another positive anal swab in two patients. CONCLUSION: "Feather sign" and "dandelion sign" were typical chest CT features in patients withCOVID-19; "pomegranate sign" was an atypical feature, and "rime sign" was a severe feature. In clinical work, accurate identification of various chest CT signs can help to improve the diagnostic accuracy of COVID-19 and reduce the misdiagnosis or missed diagnosis rate.


Asunto(s)
Betacoronavirus/aislamiento & purificación , Infecciones por Coronavirus/diagnóstico por imagen , Pulmón/patología , Neumonía Viral/diagnóstico por imagen , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Adulto , Anciano , Betacoronavirus/genética , COVID-19 , China , Infecciones por Coronavirus/patología , Femenino , Humanos , Pulmón/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Pandemias , Neumonía Viral/patología , SARS-CoV-2 , Tomografía Computarizada por Rayos X
13.
Can Assoc Radiol J ; 71(2): 195-200, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32129670

RESUMEN

Since the beginning of 2020, coronavirus disease 2019 (COVID-19) has spread throughout China. This study explains the findings from lung computed tomography images of some patients with COVID-19 treated in this medical institution and discusses the difference between COVID-19 and other lung diseases.


Asunto(s)
Infecciones por Coronavirus/diagnóstico por imagen , Neumonía Viral/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Betacoronavirus/aislamiento & purificación , COVID-19 , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pandemias , SARS-CoV-2
14.
Biochemistry ; 58(6): 575-581, 2019 02 12.
Artículo en Inglés | MEDLINE | ID: mdl-30557012

RESUMEN

The PX motif of DNA is a four-stranded structure in which two parallel juxtaposed double-helical domains are fused by crossovers at every point where the strands approach each other. Consequently, its twist and writhe are approximately half of those of conventional DNA. This property has been shown to relax supercoiled plasmid DNA under circumstances in which head-to-head homology exists within the plasmid; the homology can be either complete homology or every-other-half-turn homology, known as PX homology. It is clearly of interest to establish whether the cell contains proteins that interact with this unusual and possibly functional motif. We have examined Escherichia coli extracts to seek such a protein. We find by gel mobility studies that the PX motif is apparently bound by a cellular component. Fractionation of this binding activity reveals that the component is DNA polymerase I (Pol I). Although the PX motif binds to Pol I, we find that PX-DNA is not able to serve as a substrate for the extension of a shortened strand. We cannot say at this time whether the binding is a coincidence or whether it represents an activity of Pol I that is currently unknown. We have modeled the interaction of Pol I and PX-DNA using symmetry considerations and molecular dynamics.


Asunto(s)
ADN Polimerasa I/metabolismo , ADN Bacteriano/metabolismo , Proteínas de Escherichia coli/metabolismo , Escherichia coli/enzimología , Motivos de Nucleótidos , ADN Polimerasa I/química , Replicación del ADN , ADN Bacteriano/química , Proteínas de Escherichia coli/química , Modelos Moleculares , Conformación Proteica
15.
Environ Microbiol ; 21(5): 1740-1756, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30680880

RESUMEN

The mqsRA operon encodes a toxin-antitoxin pair that was characterized to participate in biofilm and persister cell formation in Escherichia coli. Notably, the antitoxin MqsA possesses a C-terminal DNA-binding domain that recognizes the [5'-AACCT(N)2-4 AGGTT-3'] motif and acts as a transcriptional regulator controlling multiple genes including the general stress response regulator RpoS. However, it is unknown how the transcriptional circuits of MqsA homologues have changed in bacteria over evolutionary time. Here, we found mqsA in Pseudomonas fluorescens (PfmqsA) is acquired through horizontal gene transfer and binds to a slightly different motif [5'-TACCCT(N)3 AGGGTA-3'], which exists upstream of the PfmqsRA operon. Interestingly, an adjacent GntR-type transcriptional regulator, which was termed AgtR, is under negative control of PfMqsA. It was further demonstrated that PfMqsA reduces production of biofilm components through AgtR, which directly regulates the pga and fap operons involved in the synthesis of extracellular polymeric substances. Moreover, through quantitative proteomics analysis, we showed AgtR is a highly pleiotropic regulator that influences up to 252 genes related to diverse processes including chemotaxis, oxidative phosphorylation and carbon and nitrogen metabolism. Taken together, our findings suggest the rewired regulatory circuit of PfMqsA influences diverse physiological aspects of P. fluorescens 2P24 via the newly characterized AgtR.


Asunto(s)
Proteínas Bacterianas/metabolismo , Pseudomonas fluorescens/metabolismo , Antitoxinas/genética , Antitoxinas/metabolismo , Proteínas Bacterianas/genética , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Evolución Molecular , Regulación Bacteriana de la Expresión Génica , Operón , Pseudomonas fluorescens/genética
16.
BMC Plant Biol ; 19(1): 457, 2019 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-31664905

RESUMEN

BACKGROUND: Herbicide tolerance is an important trait that allows effective weed management in wheat crops in dryland farming. Genetic knowledge of metribuzin tolerance in wheat is needed to develop new cultivars for the industry. Here, we investigated gene effects for metribuzin tolerance in nine crosses of wheat by partitioning the means and variances of six basic generations from each cross into their genetic components to assess the gene action governing the inheritance of this trait. Metribuzin tolerance was measured by a visual senescence score 21 days after treatment. The wheat 90 K iSelect SNP genotyping assay was used to identify the distribution of alleles at SNP sites in tolerant and susceptible groups. RESULTS: The scaling and joint-scaling tests indicated that the inheritance of metribuzin tolerance in wheat was adequately described by the additive-dominance model, with additive gene action the most significant factor for tolerance. The potence ratio for all the crosses ranged between - 1 and + 1 for senescence under metribuzin-treated conditions indicating a semi-dominant gene action in the inheritance of metribuzin tolerance in wheat. The number of segregating genes governing metribuzin tolerance was estimated between 3 and 15. The consistent high heritability range (0.82 to 0.92) in F5-7 generations of Chuan Mai 25 (tolerant) × Ritchie (susceptible) cross indicated a significant contribution of additive genetic effects to metribuzin tolerance in wheat. Several genes related to photosynthesis (e.g. photosynthesis system II assembly factor YCF48), metabolic detoxification of xenobiotics and cell growth and development (cytochrome P450, glutathione S-transferase, glycosyltransferase, ATP-binding cassette transporters and glutathione peroxidase) were identified on different chromosomes (2A, 2D, 3B, 4A, 4B, 7A, 7B, 7D) governing metribuzin tolerance. CONCLUSIONS: The simple additive-dominance gene effects for metribuzin tolerance will help breeders to select tolerant lines in early generations and the identified genes may guide the development of functional markers for metribuzin tolerance.


Asunto(s)
Resistencia a los Herbicidas/genética , Herbicidas/farmacología , Herencia , Polimorfismo de Nucleótido Simple , Triazinas/farmacología , Triticum/genética , Estudios de Asociación Genética , Análisis de Secuencia por Matrices de Oligonucleótidos , Fenotipo
17.
Chemistry ; 25(20): 5169-5172, 2019 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-30896074

RESUMEN

A new strategy has been established for the synthesis of polysubstituted morpholin-2-ones through Stevens rearrangements of tertiary amines via in situ activation with epoxides. A range of α-amino acid-derived tertiary allylic, propargylic, and benzylic amines reacted with epoxides in the presence of zinc halide catalysts to afford structurally diverse allyl-, allenyl-, and benzyl-substituted morpholin-2-ones, respectively, in moderate-to-good yields with high regioselectivity. The process involves [2,3]- and [1,2]-Stevens rearrangements of quaternary ammonium ylide intermediates and constitutes a very convenient method to prepare polysubstituted morpholin-2-ones through tandem formation of C-N, C-O, and C-C bonds. Moreover, replacing epoxides with aziridines permitted the synthesis of polysubstituted piperazin-2-ones.

18.
Int J Mol Sci ; 20(16)2019 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-31404956

RESUMEN

(1) Background: Upland cotton (Gossypium hirsutum L.) is the most important natural fiber worldwide, and it is extensively planted and plentifully used in the textile industry. Major cotton planting regions are frequently affected by abiotic stress, especially drought stress. Drought resistance is a complex, quantitative trait. A genome-wide association study (GWAS) constitutes an efficient method for dissecting the genetic architecture of complex traits. In this study, the drought resistance of a population of 316 upland cotton accessions was studied via GWAS. (2) Methods: GWAS methodology was employed to identify relationships between molecular markers or candidate genes and phenotypes of interest. (3) Results: A total of 8, 3, and 6 SNPs were associated with the euphylla wilting score (EWS), cotyledon wilting score (CWS), and leaf temperature (LT), respectively, based on a general linear model and a factored spectrally transformed linear mixed model. For these traits, 7 QTLs were found, of which 2 each were located on chromosomes A05, A11, and D03, and of which 1 was located on chromosome A01. Importantly, in the candidate regions WRKY70, GhCIPK6, SnRK2.6, and NET1A, which are involved in the response to abscisic acid (ABA), the mitogen-activated protein kinase (MAPK) signaling pathway and the calcium transduction pathway were identified in upland cotton at the seedling stage under drought stress according to annotation information and linkage disequilibrium (LD) block analysis. Moreover, RNA sequencing analysis showed that WRKY70, GhCIPK6, SnRK2.6, and NET1A were induced by drought stress, and the expression of these genes was significantly different between normal and drought stress conditions. (4) Conclusions: The present study should provide some genomic resources for drought resistance in upland cotton. Moreover, the germplasm of the different phenotypes, the detected SNPs and, the potential candidate genes will be helpful for molecular marker-assisted breeding studies about increased drought resistance in upland cotton.


Asunto(s)
Gossypium/genética , Polimorfismo de Nucleótido Simple , Sitios de Carácter Cuantitativo , Plantones/genética , Adaptación Fisiológica , Sequías , Regulación de la Expresión Génica de las Plantas , Estudio de Asociación del Genoma Completo , Gossypium/fisiología , Desequilibrio de Ligamiento , Plantones/fisiología , Estrés Fisiológico
19.
Fish Physiol Biochem ; 45(6): 1963-1980, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31399918

RESUMEN

Scatophagus argus is a new emerging aquaculture fish in East and Southeast Asia. To date, research on reproductive development and regulation in S. argus is lacking. Additionally, genetic and genomic information about reproduction, such as gonadal transcriptome data, is also lacking. Herein, we report the first gonadal transcriptomes of S. argus and identify genes potentially involved in reproduction and gonadal development. A total of 136,561 unigenes were obtained by sequencing of testes (n = 3) and ovaries (n = 3) at stage III. Genes upregulated in males and females known to be involved in gonadal development and gametogenesis were identified, including male-biased dmrt1, amh, gsdf, wt1a, sox9b, and nanos2, and female-biased foxl2, gdf9, bmp15, sox3, zar1, and figla. Serum estradiol-17ß and 11-ketotestosterone levels were biased in female and male fish, respectively. Sexual dimorphism of serum steroid hormone levels were interpreted after expression analysis of 20 steroidogenesis-related genes, including cyp19a1a and cyp11b2. This gonadal transcript dataset will help investigate functional genes related to reproduction in S. argus.


Asunto(s)
Peces/genética , Gónadas/fisiología , Caracteres Sexuales , Transcriptoma , Animales , Femenino , Hormonas Esteroides Gonadales/sangre , Masculino , RNA-Seq
20.
Bull Environ Contam Toxicol ; 103(5): 729-733, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31531704

RESUMEN

Accumulation of nonylphenol (NP) in hepatopancreas, gonad, eyestalk, and muscle of freshwater prawn Macrobrachium rosenbergii following 72 h exposure to 100 µg/L NP, and depuration of NP in these tissues at 0.5-192 h post exposure were examined. We also examined the expressions of vitellogenin (Vg) and vitellogenin receptor (VgR) of prawn following 0-20 days exposure to 0, 1, 10, and 100 µg/L NP. NP accumulation in hepatopancreas and gonad with high concentration, and low concentration in muscle, but depurated faster in eyestalk and muscle. The expressions of vitellogenin (Vg) and vitellogenin receptor (VgR) increased directly with dose and time. In conclusion, NP accumulated significantly in gonad together with high Vg and VgR expressions, and depurated slow in hepatopancreas and gonad when prawns were removed back to control water. The induction of Vg and VgR under NP exposure might be a stress response in M. rosenbergii.


Asunto(s)
Proteínas del Huevo/genética , Agua Dulce/química , Palaemonidae/efectos de los fármacos , Fenoles/toxicidad , Receptores de Superficie Celular/genética , Vitelogeninas/genética , Contaminantes Químicos del Agua/toxicidad , Animales , Bioacumulación/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Expresión Génica/efectos de los fármacos , Gónadas/efectos de los fármacos , Gónadas/metabolismo , Hepatopáncreas/efectos de los fármacos , Hepatopáncreas/metabolismo , Tasa de Depuración Metabólica , Palaemonidae/metabolismo , Fenoles/metabolismo , Contaminantes Químicos del Agua/metabolismo
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