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1.
Orthop Surg ; 16(5): 1143-1152, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38561920

RESUMEN

OBJECTIVE: Medial opening-wedge high tibial osteotomy (MOWHTO) is a surgical procedure to treat medial compartment osteoarthritis in the knee with varus deformity. However, factors such as patellar height (PH) and the sagittal plane's posterior tibial slope angle (PTSA) are potentially overlooked. This study investigated the impact of alignment correction angle guided by computer-designed personalized surgical guide plate (PSGP) in MOWHTO on PH and PTSA, offering insights for enhancing surgical techniques. METHODS: This retrospective study included patients who underwent 3D-printed PSGP-assisted MOWHTO at our institution from March to September 2022. The paired t-tests assessed differences in all preoperative and postoperative measurement parameters. Multivariate linear regression analysis examined correlations between PTSA, CDI (Caton-Deschamps Index), and the alignment correction magnitude. Receiver operating characteristic (ROC) curve analysis determined the threshold of the correction angle, calculating sensitivity, specificity, and area under the curve. RESULTS: A total of 107 patients were included in our study. The CDI changed from a preoperative mean of 0.97 ± 0.13 (range 0.70-1.34) to a postoperative mean of 0.82 ± 0.13 (range 0.55-1.20). PTSA changed from a preoperative mean of 8.54 ± 2.67 (range 2.19-17.55) to a postoperative mean of 10.54 ± 3.05 (range 4.48-18.05). The t-test revealed statistically significant changes in both values (p < 0.05). A significant alteration in patellar height occurred when the correction angle exceeded 9.39°. Moreover, this paper illustrates a negative correlation between CDI change and the correction angle and preoperative PTSA. Holding other factors constant, each 1-degree increase in the correction angle led to a 0.017 decrease in postoperative CDI, and each 1-degree increase in preoperative PTSA resulted in a 0.008 decrease in postoperative CDI. PTSA change was positively correlated only with the correction angle; for each 1-degree increase in the opening angle, postoperative PTS increased by 0.188, with other factors constant. CONCLUSION: This study highlights the effectiveness and precision of PSGP-assisted MOWHTO, focusing on the impact of alignment correction on PH and PTSA. These findings support the optimization of PSGP technology, which offers simpler, faster, and safer surgeries with less radiation and bleeding than traditional methods. However, PSGP's one-time use design and the learning curve required for its application are limitations, suggesting areas for further research.


Asunto(s)
Osteoartritis de la Rodilla , Osteotomía , Rótula , Cirugía Asistida por Computador , Tibia , Humanos , Estudios Retrospectivos , Osteotomía/métodos , Femenino , Masculino , Persona de Mediana Edad , Tibia/cirugía , Rótula/cirugía , Adulto , Osteoartritis de la Rodilla/cirugía , Cirugía Asistida por Computador/métodos , Anciano , Impresión Tridimensional
2.
EClinicalMedicine ; 64: 102243, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37936654

RESUMEN

Background: The proportion of young breast cancer patients in China is significantly higher than in Western countries, and the clinicopathological characteristics and clinical problems faced by patients in China are different from those in Western countries too, so there is an urgent need to conduct some studies for young breast cancer patients in Asia. Methods: This study consisted of two breast cancer cohorts in China. The population-based cohort involved breast cancer cases diagnosed in 2000-2017 via cancer registration system, and we describe the epidemiological characteristics of the young breast cancer in China. The hospital-based cohort, patients eligible for enrollment were breast cancer in young women (≤35 years old) from eight centres in different regions of China, diagnosed and treated for the first time in six time periods (i.e., 2000, 2003, 2006, 2009, 2012, and 2015). Patient demographic characteristics and clinical features were compared among the six time periods using a trend test. The Kaplan-Meier method was used to generate survival curves, and the log-rank test was performed to compare OS and DFS. Univariate and multivariate analyses were carried out using Cox proportional hazards regression to estimate hazard ratios (HR) and 95% confidence intervals (CIs). Findings: In the population-based cohort, age-specific incidence and age-standardised percentages of breast cancer cases younger than 35 years were increased. The proportion of breast cancer under the age of 35 is increasing more rapidly in rural areas than in urban areas. In the hospital-based cohort, a total of 1308 young breast cancer patients (≤35 years old) were collected. Proportion of patients treated with adjuvant taxane or anthracycline combined with taxane is gradually increasing over the six time periods, and the proportion of patients undergoing breast-conserving surgery is gradually increasing too. Meanwhile, the patients treated with combined ovarian function suppression (OFS) endocrine therapy gradually increased, and the duration of endocrine therapy gradually longer. There is an increasing trend in 5-year disease-free survival (DFS) rate for the total population in the six time periods between 2000 and 2015, but no significant difference in overall survival (OS) rate was observed. Early staging and longer duration of endocrine therapy were factors associated with a favorable prognosis. Interpretation: The incidence of younger breast cancers under 35 years of age has gradually increased and the pattern of patient care has changed significantly over time, which may contribute to the improved prognosis of younger breast cancer patients. Funding: Beijing Medical Award Foundation (YXJL-2020-0941-0763), Beijing Hope Run Special Fund of Cancer Foundation of China (LC2021L04), Chinese Academy of Medical Sciences Clinical Translational and Medical Research Fund (2022-I2M-C&T-A-014).

3.
BMC Res Notes ; 12(1): 522, 2019 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-31426836

RESUMEN

OBJECTIVE: Soybean seed development is negatively impacted by elevated temperatures during seed fill, which can decrease seed quality and economic value. Prior germplasm screens identified an exotic landrace able to maintain ~ 95% seed germination under stress conditions that reduce germination dramatically (> 50%) for typical soybean seeds. Seed transcriptomic analysis was performed for two soybean lines (a heat-tolerant landrace and a typical high-yielding adapted line) for dry, mature seed, 6-h imbibed seed and germinated seed. Seeds were produced in two environments: a typical Midwestern field and a heat stressed field located in the Midsouth soybean production region. RESULTS: Transcriptomic analysis revealed 23-30K expressed genes in each seed tissue sample, and differentially expressed genes (DEGs) with ≥ twofold gene expression differences (at q-value < 0.05) comprised ~ 5-44% of expressed genes. Gene ontology (GO) enrichment analysis on DEGs revealed enrichment in heat-tolerant seeds for genes annotated for general and temperature-specific stress, as well as protein-refolding. DEGs were also clustered in modules using weighted co-expressed gene network analysis, which were examined for enrichment of GO biological process terms. Collectively, our results provide new and valuable insights into this unique form of genetic abiotic stress tolerance and to soybean seed physiological responses to elevated temperatures.


Asunto(s)
Adaptación Fisiológica/genética , Germinación/genética , Glycine max/genética , Calor , Semillas/genética , Transcriptoma/genética , Perfilación de la Expresión Génica/métodos , Regulación del Desarrollo de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Ontología de Genes , Redes Reguladoras de Genes , Genotipo , Peso Molecular , Semillas/crecimiento & desarrollo , Proteínas de Soja/química , Proteínas de Soja/genética , Glycine max/clasificación , Glycine max/crecimiento & desarrollo , Especificidad de la Especie
4.
Mol Clin Oncol ; 10(1): 67-77, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30655979

RESUMEN

Lung cancer is one of the leading causes of cancer-associated mortality throughout the world. The prognosis of the disease depends on many factors including the stage and type of cancer. Many studies have identified various microRNAs (miRNAs) that affect the prognosis of lung cancer. In order to systemically analyze the available clinical data, the present study performed a meta-analysis to examine all evidence on the potential role of miRNAs as novel predictors of survival in lung cancer. Literature published in English prior to February 1st, 2018 was searched through PubMed to review all of the associations between individual miRNAs and groups of miRNAs with the prognosis of lung cancer. Data was extracted using standard forms and pooled odds ratios with 95% confidence intervals (CIs) were calculated. A total of 15 eligible studies were included in the meta-analysis. These represented 1,753 lung cancer patients and 20 miRNAs. A total of 8 downregulated miRNAs were associated with poorer overall survival (OS) [hazard ratio (HR)=0.59, 95% CI: 0.47-0.75, P<1×10-4], while 10 upregulated miRNAs were associated with poorer OS (HR=1.76, 95% CI: 1.31-2.35, P<1×10-4). Additionally, low miRNA expression was associated with lymph node metastasis [LNM; relative risk (RR)=0.53, 95% CI: 0.46-0.61, P<1×10-4]. The expression of miRNAs was not associated with lung cancer stage (RR=1.07, 95% CI: 0.94-1.22, P=0.23). Expression levels of different miRNAs were associated with the OS and LNM of patients with lung cancer. These miRNAs may be applied as potential prognostic markers in lung cancer.

5.
Plant Physiol ; 169(1): 594-610, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26143249

RESUMEN

The wild strawberry (Fragaria vesca) has recently emerged as an excellent model for cultivated strawberry (Fragaria × ananassa) as well as other Rosaceae fruit crops due to its short seed-to-fruit cycle, diploidy, and sequenced genome. Deep sequencing and parallel analysis of RNA ends were used to identify F. vesca microRNAs (miRNAs) and their target genes, respectively. Thirty-eight novel and 31 known miRNAs were identified. Many known miRNAs targeted not only conserved mRNA targets but also developed new target genes in F. vesca. Significantly, two new clusters of miRNAs were found to collectively target 94 F-BOX (FBX) genes. One of the miRNAs in the new cluster is 22 nucleotides and triggers phased small interfering RNA production from six FBX genes, which amplifies the silencing to additional FBX genes. Comparative genomics revealed that the main novel miRNA cluster evolved from duplications of FBX genes. Finally, conserved trans-acting siRNA pathways were characterized and confirmed with distinct features. Our work identified novel miRNA-FBX networks in F. vesca and shed light on the evolution of miRNAs/phased small interfering RNA networks that regulate large gene families in higher plants.


Asunto(s)
Diploidia , Evolución Molecular , Fragaria/genética , Regulación de la Expresión Génica de las Plantas , Redes Reguladoras de Genes , MicroARNs/genética , ARN Interferente Pequeño/metabolismo , Secuencia de Bases , Secuencia Conservada/genética , Flores/genética , Frutas/genética , Duplicación de Gen , Perfilación de la Expresión Génica , Genes de Plantas , MicroARNs/metabolismo , Modelos Genéticos , Datos de Secuencia Molecular , Motivos de Nucleótidos , ARN Mensajero/genética , ARN Mensajero/metabolismo
6.
Plant Cell ; 25(5): 1555-72, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23695981

RESUMEN

Trans-acting small interfering RNAs (tasiRNAs) are a major class of small RNAs performing essential biological functions in plants. The first reported tasiRNA pathway, that of miR173-TAS1/2, produces tasiRNAs regulating a set of pentatricopeptide repeat (PPR) genes and has been characterized only in Arabidopsis thaliana to date. Here, we demonstrate that the microRNA (miRNA)-trans-acting small interfering RNA gene (TAS)-pentatricopeptide repeat-containing gene (PPR)-small interfering RNA pathway is a highly dynamic and widespread feature of eudicots. Nine eudicot plants, representing six different plant families, have evolved similar tasiRNA pathways to initiate phased small interfering RNA (phasiRNA) production from PPR genes. The PPR phasiRNA production is triggered by different 22-nucleotide miRNAs, including miR7122, miR1509, and fve-PPRtri1/2, and through distinct mechanistic strategies exploiting miRNA direct targeting or indirect targeting through TAS-like genes (TASL), one-hit or two-hit, or even two layers of tasiRNA-TASL interactions. Intriguingly, although those miRNA triggers display high sequence divergence caused by the occurrence of frequent point mutations and splicing shifts, their corresponding MIRNA genes show pronounced identity to the Arabidopsis MIR173, implying a common origin of this group of miRNAs (super-miR7122). Further analyses reveal that super-miR7122 may have evolved from a newly defined miR4376 superfamily, which probably originated from the widely conserved miR390. The elucidation of this evolutionary path expands our understanding of the course of miRNA evolution, especially for relatively conserved miRNA families.


Asunto(s)
Magnoliopsida/genética , MicroARNs/genética , Familia de Multigenes , ARN de Planta/genética , ARN Interferente Pequeño/genética , Proteínas de Arabidopsis/genética , Secuencia de Bases , Cotiledón/clasificación , Cotiledón/genética , Evolución Molecular , Fragaria/genética , Variación Genética , Magnoliopsida/clasificación , Malus/genética , Medicago/genética , Datos de Secuencia Molecular , Filogenia , Prunus/genética , Homología de Secuencia de Ácido Nucleico , Transducción de Señal/genética , Glycine max/genética , Especificidad de la Especie , Vitis/genética
7.
Plant Physiol ; 162(2): 965-76, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23580592

RESUMEN

The phytohormone auxin regulates virtually every aspect of plant development. To identify new genes involved in auxin activity, a genetic screen was performed for Arabidopsis (Arabidopsis thaliana) mutants with altered expression of the auxin-responsive reporter DR5rev:GFP. One of the mutants recovered in the screen, designated as weak auxin response3 (wxr3), exhibits much lower DR5rev:GFP expression when treated with the synthetic auxin 2,4-dichlorophenoxyacetic acid and displays severe defects in root development. The wxr3 mutant decreases polar auxin transport and results in a disruption of the asymmetric auxin distribution. The levels of the auxin transporters AUXIN1 and PIN-FORMED are dramatically reduced in the wxr3 root tip. Molecular analyses demonstrate that WXR3 is ROOT ULTRAVIOLET B-SENSITIVE1 (RUS1), a member of the conserved Domain of Unknown Function647 protein family found in diverse eukaryotic organisms. Our data suggest that RUS1/WXR3 plays an essential role in the regulation of polar auxin transport by maintaining the proper level of auxin transporters on the plasma membrane.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Ácidos Indolacéticos/metabolismo , Ácido 2,4-Diclorofenoxiacético/farmacología , Arabidopsis/efectos de los fármacos , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Transporte Biológico/genética , Membrana Celular/metabolismo , Endosomas/metabolismo , Proteínas F-Box/genética , Proteínas F-Box/metabolismo , Proteínas de Transporte de Membrana/genética , Proteínas de Transporte de Membrana/metabolismo , Meristema/genética , Meristema/metabolismo , Mutación , Raíces de Plantas/genética , Raíces de Plantas/crecimiento & desarrollo , Plantas Modificadas Genéticamente , Receptores de Superficie Celular/genética , Receptores de Superficie Celular/metabolismo , Transducción de Señal
8.
Proc Natl Acad Sci U S A ; 108(50): 20231-5, 2011 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-22123947

RESUMEN

At high ambient temperature, plants display dramatic stem elongation in an adaptive response to heat. This response is mediated by elevated levels of the phytohormone auxin and requires auxin biosynthesis, signaling, and transport pathways. The mechanisms by which higher temperature results in greater auxin accumulation are unknown, however. A basic helix-loop-helix transcription factor, PHYTOCHROME-INTERACTING FACTOR 4 (PIF4), is also required for hypocotyl elongation in response to high temperature. PIF4 also acts redundantly with its homolog, PIF5, to regulate diurnal growth rhythms and elongation responses to the threat of vegetative shade. PIF4 activity is reportedly limited in part by binding to both the basic helix-loop-helix protein LONG HYPOCOTYL IN FAR RED 1 and the DELLA family of growth-repressing proteins. Despite the importance of PIF4 in integrating multiple environmental signals, the mechanisms by which PIF4 controls growth are unknown. Here we demonstrate that PIF4 regulates levels of auxin and the expression of key auxin biosynthesis genes at high temperature. We also identify a family of SMALL AUXIN UP RNA (SAUR) genes that are expressed at high temperature in a PIF4-dependent manner and promote elongation growth. Taken together, our results demonstrate direct molecular links among PIF4, auxin, and elongation growth at high temperature.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Calor , Ácidos Indolacéticos/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Regulación de la Expresión Génica de las Plantas , Genes de Plantas/genética , Regiones Promotoras Genéticas/genética , Unión Proteica
9.
Cell Res ; 20(5): 539-52, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20354503

RESUMEN

Jasmonic acid (JA) is a fatty acid-derived signaling molecule that regulates a broad range of plant defense responses against herbivores and some microbial pathogens. Molecular genetic studies have established that JA also performs a critical role in several aspects of plant development. Here, we describe the characterization of the Arabidopsis mutant jasmonic acid-hypersensitive1-1 (jah1-1), which is defective in several aspects of JA responses. Although the mutant exhibits increased sensitivity to JA in root growth inhibition, it shows decreased expression of JA-inducible defense genes and reduced resistance to the necrotrophic fungus Botrytis cinerea . Gene cloning studies indicate that these defects are caused by a mutation in the cytochrome P450 protein CYP82C2. We provide evidence showing that the compromised resistance of the jah1-1 mutant to B . cinerea is accompanied by decreased expression of JA-induced defense genes and reduced accumulation of JA-induced indole glucosinolates (IGs). Conversely, the enhanced resistance to B. cinerea in CYP82C2-overexpressing plants is accompanied by increased expression of JA-induced defense genes and elevated levels of JA-induced IGs. We demonstrate that CYP82C2 affects JA-induced accumulation of the IG biosynthetic precursor tryptophan (Trp), but not the JA-induced IAA or pathogen-induced camalexin. Together, our results support a hypothesis that CYP82C2 may act in the metabolism of Trp-derived secondary metabolites under conditions in which JA levels are elevated. The jah1-1 mutant should thus be important in future studies toward understanding the mechanisms underlying the complexity of JA-mediated differential responses, which are important for plants to adapt their growth to the ever-changing environments.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Arabidopsis/microbiología , Ciclopentanos/metabolismo , Sistema Enzimático del Citocromo P-450/metabolismo , Regulación de la Expresión Génica de las Plantas , Glucosinolatos/metabolismo , Oxilipinas/metabolismo , Raíces de Plantas/crecimiento & desarrollo , Arabidopsis/genética , Arabidopsis/crecimiento & desarrollo , Botrytis/patogenicidad , Genes de Plantas , Indoles/metabolismo , Mutación , Enfermedades de las Plantas
10.
Plant Cell ; 21(5): 1495-511, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19435934

RESUMEN

Plant roots show an impressive degree of plasticity in adapting their branching patterns to ever-changing growth conditions. An important mechanism underlying this adaptation ability is the interaction between hormonal and developmental signals. Here, we analyze the interaction of jasmonate with auxin to regulate lateral root (LR) formation through characterization of an Arabidopsis thaliana mutant, jasmonate-induced defective lateral root1 (jdl1/asa1-1). We demonstrate that, whereas exogenous jasmonate promotes LR formation in wild-type plants, it represses LR formation in jdl1/asa1-1. JDL1 encodes the auxin biosynthetic gene ANTHRANILATE SYNTHASE alpha1 (ASA1), which is required for jasmonate-induced auxin biosynthesis. Jasmonate elevates local auxin accumulation in the basal meristem of wild-type roots but reduces local auxin accumulation in the basal meristem of mutant roots, suggesting that, in addition to activating ASA1-dependent auxin biosynthesis, jasmonate also affects auxin transport. Indeed, jasmonate modifies the expression of auxin transport genes in an ASA1-dependent manner. We further provide evidence showing that the action mechanism of jasmonate to regulate LR formation through ASA1 differs from that of ethylene. Our results highlight the importance of ASA1 in jasmonate-induced auxin biosynthesis and reveal a role for jasmonate in the attenuation of auxin transport in the root and the fine-tuning of local auxin distribution in the root basal meristem.


Asunto(s)
Acetatos/farmacología , Antranilato Sintasa/farmacología , Proteínas de Arabidopsis/fisiología , Arabidopsis/metabolismo , Ciclopentanos/farmacología , Ácidos Indolacéticos/metabolismo , Oxilipinas/farmacología , Acetatos/metabolismo , Antranilato Sintasa/genética , Antranilato Sintasa/metabolismo , Arabidopsis/efectos de los fármacos , Arabidopsis/fisiología , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/farmacología , Transporte Biológico/efectos de los fármacos , Ciclopentanos/metabolismo , Etilenos/farmacología , Mutación , Oxilipinas/metabolismo , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/genética , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/metabolismo
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