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1.
Plant Cell ; 36(5): 1755-1776, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38318972

RESUMEN

The milestone of compound leaf development is the generation of separate leaflet primordia during the early stages, which involves two linked but distinct morphogenetic events: leaflet initiation and boundary establishment for leaflet separation. Although some progress in understanding the regulatory pathways for each event have been made, it is unclear how they are intrinsically coordinated. Here, we identify the PINNATE-LIKE PENTAFOLIATA2 (PINNA2) gene encoding a newly identified GRAS transcription factor in Medicago truncatula. PINNA2 transcripts are preferentially detected at organ boundaries. Its loss-of-function mutations convert trifoliate leaves into a pinnate pentafoliate pattern. PINNA2 directly binds to the promoter region of the LEAFY orthologue SINGLE LEAFLET1 (SGL1), which encodes a key positive regulator of leaflet initiation, and downregulates its expression. Further analysis revealed that PINNA2 synergizes with two other repressors of SGL1 expression, the BEL1-like homeodomain protein PINNA1 and the C2H2 zinc finger protein PALMATE-LIKE PENTAFOLIATA1 (PALM1), to precisely define the spatiotemporal expression of SGL1 in compound leaf primordia, thereby maintaining a proper pattern of leaflet initiation. Moreover, we showed that the enriched expression of PINNA2 at the leaflet-to-leaflet boundaries is positively regulated by the boundary-specific gene MtNAM, which is essential for leaflet boundary formation. Together, these results unveil a pivotal role of the boundary-expressed transcription factor PINNA2 in regulating leaflet initiation, providing molecular insights into the coordination of intricate developmental processes underlying compound leaf pattern formation.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Medicago truncatula , Hojas de la Planta , Medicago truncatula/genética , Medicago truncatula/crecimiento & desarrollo , Medicago truncatula/metabolismo , Morfogénesis/genética , Hojas de la Planta/genética , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente , Regiones Promotoras Genéticas/genética , Factores de Transcripción/metabolismo , Factores de Transcripción/genética
2.
J Asian Nat Prod Res ; 26(2): 237-247, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37812065

RESUMEN

Three new phenylpropanoid glycosides, piperpubelide (1), 1-propionyl-3-hydroxy-phenyl-4-O-ß-D-glucopyranoside (2), and 1-propionyl-4-hydroxy-phenyl-3-O-ß-D-glucopyranoside (3), a new tyramine-type alkamide, puberulumine L (4), together with thirteen known compounds (5-17) were isolated from Piper puberulum (Benth.) Maxim. Their structures were elucidated by analysis of spectroscopic data involving NMR, IR, UV, and HRESIMS data. Calculated and experimental ECD was used to confirm the configuration of compound 1. Compounds 14, 16, and 17 exhibited relatively positive DPPH radical scavenging activities, with corresponding EC50 of 10.23, 24.12, and 21.83 µM, respectively. In addition, compound 5 inhibited LPS-induced NO production in BV-2 microglia with an IC50 value of 18.05 µM.


Asunto(s)
Glucósidos , Piper , Glucósidos/farmacología , Glucósidos/química , Piper/química , Tiramina/farmacología , Tiramina/química , Estructura Molecular , Glicósidos/farmacología , Glicósidos/química
3.
Nat Commun ; 14(1): 8088, 2023 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-38062032

RESUMEN

Plant lateral organs are often elaborated through repetitive formation of developmental units, which progress robustly in predetermined patterns along their axes. Leaflets in compound leaves provide an example of such units that are generated sequentially along the longitudinal axis, in species-specific patterns. In this context, we explored the molecular mechanisms underlying an acropetal mode of leaflet initiation in chickpea pinnate compound leaf patterning. By analyzing naturally occurring mutants multi-pinnate leaf1 (mpl1) that develop higher-ordered pinnate leaves with more than forty leaflets, we show that MPL1 encoding a C2H2-zinc finger protein sculpts a morphogenetic gradient along the proximodistal axis of the early leaf primordium, thereby conferring the acropetal leaflet formation. This is achieved by defining the spatiotemporal expression pattern of CaLEAFY, a key regulator of leaflet initiation, and also perhaps by modulating the auxin signaling pathway. Our work provides novel molecular insights into the sequential progression of leaflet formation.


Asunto(s)
Cicer , Cicer/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulación de la Expresión Génica de las Plantas , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Morfogénesis , Ácidos Indolacéticos/metabolismo
4.
J Am Chem Soc ; 145(36): 20031-20040, 2023 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-37642381

RESUMEN

Albeit notable endeavors in enantioselective carbene insertion into X-H bonds (X = C, O, N, S, Si, B), the catalytic asymmetric P-H insertion reactions still stand for a long-lasting challenge. By merging transition-metal catalysis with organocatalysis, we achieve a scalable enantioselective P-H insertion transformation between diazo pyrazoleamides and H-phosphine oxides that upon subsequent reduction delivers a wide variety of optically active ß-hydroxyl phosphine oxides in good yields with high enantioselectivity. The achiral copper catalyst fosters the carbenoid insertion into the P-H bond, while the chiral cinchona alkaloid-derived organocatalyst controls the subsequent enantioselective outcome. Density functional theory (DFT) calculations further reveal that the copper catalyst chelates to the organocatalyst, enhances its acidity, and accordingly promotes the enantioselective proton transfer. Our work showcases the potential of combining transition-metal catalysis with organocatalysis to realize elusive asymmetric reactions.

5.
BMC Womens Health ; 23(1): 252, 2023 05 10.
Artículo en Inglés | MEDLINE | ID: mdl-37165420

RESUMEN

BACKGROUND: Choriocarcinoma coexisting with endometrial carcinoma is rare. To the best of our knowledge, only one case of choriocarcinoma coexisting with endometrial carcinoma has been reported. CASE PRESENTATION: Here, we present this case and provide a literature review. A 38-year-old unmarried nulliparous woman presented to the clinic with a menstrual disorder for more than 3 months. She then underwent a hysteroscopic procedure. The pathological findings were malignant, two types of carcinoma, and no transitional lesions were observed; about 85% of them were choriocarcinoma with smooth muscle infiltration and intravascular investigation of the thrombus; about 15% were highly differentiated endometrioid adenocarcinoma; Immunohistochemistry (endometrioid/choriocarcinoma): Vim (+ + / + + +), P40 (+ ±), CK5/6 multifocal ( ±), CK7 ( ±), EMA (+ ±), P16 multifocal ( ±), P53 (+ / + +), WT-1 (-/ + +), hCG (-/ + + +), CD138 (-/ + + +), Gly-3 (-/-), ER ( ±), PR (+ ±), Sall-4 (-/-), P21 (-/ +), P27 (-/ + + +), CyclinE (-/ + +), Ki67 positivity rate (10%/95%). We performed a laparoscopic hysterectomy, bilateral adnexectomy, and pelvic and para-abdominal lymph node dissection after five cycles of chemotherapy. She was diagnosed with choriocarcinoma with endometrial cancer, stage IVb choriocarcinoma and stage IA endometrial cancer. Postoperative radiochemotherapy was administered. The patient was disease-free 40 months after the treatment ended. CONCLUSION: We report a case of choriocarcinoma coexisting with endometrial carcinoma and provide a literature review that may help inspire additional studies in the future.


Asunto(s)
Carcinoma Endometrioide , Quimioradioterapia , Coriocarcinoma , Neoplasias Endometriales , Histerectomía , Neoplasias Uterinas , Humanos , Femenino , Embarazo , Adulto , Coriocarcinoma/patología , Coriocarcinoma/terapia , Neoplasias Uterinas/patología , Neoplasias Uterinas/terapia , Carcinoma Endometrioide/patología , Carcinoma Endometrioide/terapia , Neoplasias Endometriales/patología , Neoplasias Endometriales/terapia , Endometrio/patología , Laparoscopía , Estadificación de Neoplasias , Resultado del Tratamiento
6.
Org Lett ; 25(13): 2338-2343, 2023 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-36975042

RESUMEN

An intriguing visible-light-induced strategy has been established for the P-H insertion reaction between acylsilanes and H-phosphorus oxides that, upon a subsequent acidic process, deliver a wide variety of α-hydroxyphosphorus oxides in good yields (up to 93% yield). The metal-free protocol represents a unique example of P-H insertion for C-P bond formation through in situ generation of siloxycarbenes. This methodology features the advantages of operational simplicity, mild conditions, broad substrate scope, and column free in gram-scale synthesis.

8.
J Environ Manage ; 312: 114900, 2022 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-35313149

RESUMEN

The leaching of nitrogen in farmland could lead to groundwater nitrogen pollution, while precipitation is the driving factor. Nevertheless, the influences of extreme precipitation on soil organic nitrogen leaching, such as urea, is not clear. In this study, we used soil column experimental data to construct a nitrogen migration and transformation model. The constructed model was applied to unsaturated zones in farmlands in the Dagu River Basin of China. Three rainfall scenarios, namely rainstorms, heavy rainstorms, and extreme rainstorms, were simulated to analyze the variation in urea nitrogen leaching to groundwater. As the rainfall intensity increased, the quantity of urea nitrogen leaching increased from 0.04% to 18.09%. The cumulative urea nitrogen leaching flux is related to the initial soil moisture content. The time interval between fertilization inversely influenced the urea nitrogen leaching flux. Applying urea-based fertilizers shortly before high-intensity rainfall significantly increases the soil-crop system urea leaching loss and decreases crop nitrogen utilization. These findings imply that urea leaching under extreme rainstorms should not be ignored, and based on weather forecasting, fertilizer application in farmland should be avoided before high-intensity rainfall.


Asunto(s)
Agua Subterránea , Nitrógeno , Agricultura , Fertilizantes/análisis , Nitrógeno/análisis , Suelo , Urea
9.
IEEE Trans Pattern Anal Mach Intell ; 44(2): 684-696, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-30990419

RESUMEN

Grounding natural language in images, such as localizing "the black dog on the left of the tree", is one of the core problems in artificial intelligence, as it needs to comprehend the fine-grained language compositions. However, existing solutions merely rely on the association between the holistic language features and visual features, while neglect the nature of composite reasoning implied in the language. In this paper, we propose a natural language grounding model that can automatically compose a binary tree structure for parsing the language and then perform visual reasoning along the tree in a bottom-up fashion. We call our model RvG-Tree: Recursive Grounding Tree, which is inspired by the intuition that any language expression can be recursively decomposed into two constituent parts, and the grounding confidence score can be recursively accumulated by calculating their grounding scores returned by the two sub-trees.RvG-Tree can be trained end-to-end by using the Straight-Through Gumbel-Softmax estimator that allows the gradients from the continuous score functions passing through the discrete tree construction. Experiments on several benchmarks show that our model achieves the state-of-the-art performance with more explainable reasoning.


Asunto(s)
Inteligencia Artificial , Lenguaje , Algoritmos , Humanos , Aprendizaje
10.
Front Plant Sci ; 12: 749989, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35095943

RESUMEN

Simple and compound which are the two basic types of leaves are distinguished by the pattern of the distribution of blades on the petiole. Compared to simple leaves comprising a single blade, compound leaves have multiple blade units and exhibit more complex and diverse patterns of organ organization, and the molecular mechanisms underlying their pattern formation are receiving more and more attention in recent years. Studies in model legume Medicago truncatula have led to an improved understanding of the genetic control of the compound leaf patterning. This review is an attempt to summarize the current knowledge about the compound leaf morphogenesis of M. truncatula, with a focus on the molecular mechanisms involved in pattern formation. It also includes some comparisons of the molecular mechanisms between leaf morphogenesis of different model species and offers useful information for the molecular design of legume crops.

11.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 50(1): 115-118, 2019 Jan.
Artículo en Chino | MEDLINE | ID: mdl-31037913

RESUMEN

OBJECTIVE: To determine risk factors associated with intraoperative blood loss in patients with early cervical cancer (stage ⅠB-ⅡA). METHODS: The medical records of 892 patients who underwent surgical treatments for early cervical cancer in the Second West China University Hospital of from Dec 2010 to Sep 2017 were retrospectively reviewed: 127 having ≥500 mL intraoperative blood loss patients compared with 765 less than 500 mL. Differences between the two groups in age, body mass index (BMI), gravidity, history of abdominal and pelvic operations, chronic pelvic inflammation disease, clinical stage, methods of operation, neoadjuvant chemotherapy (NACT) and post-NACT operative opportunity, preoperative and postoperative hemoglobin, and intraoperative transfusion volume were analyzed through univariate and multivariate statistical methods. RESULTS: The univariate analyses identified age, BMI, gravidity, history of abdominal and pelvic operation, chronic pelvic inflammation disease, clinical stage, methods of operation, NACT and post-NACT operative opportunity assignificant factors associated with intraoperative blood loss ( P<0.05). The multivariate logistic regression analysis confirmed that age ≥40 yr. [partial regression coefficient (B)=2.100)], BMI ≥24 kg/m2 (relative to 18.5-23.9 kg/m2)(B=1.842) , clinical stage ⅡA (relative to phase ⅠB, B=2.401) , trans-abdominal operative method (relative to laparoscopy, B=1.347), no NACT (B=1.540) and post-NACT operative opportunity <2 or >3 weeks (relative to within 2-3 weeks) (B=1.723) were independent predictors of higher intraoperative blood loss (≥500 mL). CONCLUSION: Clinical stage and age, etc. are risk factors associated with intraoperative blood loss in patients with early cervical cancer.


Asunto(s)
Neoplasias del Cuello Uterino , Pérdida de Sangre Quirúrgica , China , Femenino , Humanos , Histerectomía , Estadificación de Neoplasias , Estudios Retrospectivos , Factores de Riesgo
12.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 48(4): 531-536, 2017 Jul.
Artículo en Chino | MEDLINE | ID: mdl-28752970

RESUMEN

OBJECTIVE: To determine whether hAECs can differentiate into follicle-like structure. METHODS: hAECs were isolated from human term placenta and cultured sequentially in medium supplemented with 5% human follicular fluid. The morphology of the cells was examined by inverted microscope. Changes of estradiol levels and expressions of germ cell specific gene in the cultured medium were detected by chemiluminescence immunoassay and Real time-Polymerase Chain Reaction (RT-PCR), respectively. RESULTS: Oocyte-like cells (OLCs) were found in those cultured in the medium supplemented with 5% human follicular fluid. The OLCs gradually aggrandized, shrunk and finally disappeared over time. However, this phenomenon was not observed in the control group. Higher expressions ofDAZLandGDF9were found in the follicle group compared with the control which medium without 5% human follicular fluid (P< 0.05), with two peaks. No significant difference in the expression ofSCP3was found between the two groups (P>0.05). Estradiol was detected in the culture medium of the follicle group in a mode of decreasing-rising-decreasing, but not in the control group. CONCLUSION: hAECs have the potential to trans-differentiate into the follicle-like structure in vitro.


Asunto(s)
Amnios/citología , Transdiferenciación Celular , Células Epiteliales/citología , Folículo Ovárico/citología , Células Cultivadas , Femenino , Células Germinativas/citología , Humanos , Embarazo
13.
Mol Biol Rep ; 38(8): 5133-8, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21246287

RESUMEN

IGFI signaling pathway is sufficient to regulate myofibre hypertrophy postnatally, which is associated with muscle mass in economically livestock. In the present study, we drafted the developmental expression pattern of eight genes implicated in IGFI system across six stages of postnatal myofibre growth in Yorkshire and Tongcheng pigs. The results indicated that GRB2 may contribute to increased DNA content in postnatal myofibre hypertrophy via GRB2-Ras-Raf-MEK-ERK sub-pathway; INSR, PDK1, IRS1 and eIF4E may contribute to high growth rate via stimulating the rate of protein synthesis and inhibiting the rate of protein degradation. In addition, the results suggested 60 days maybe a very important stage in postnatal myofibre growth. Moreover, higher mRNA level of IRS1 and GLUT4 maybe associated with inferior meat quality in Yorkshire compared to Tongcheng pig. Therefore, IGFI signaling pathway regulates myofibre hypertrophy postnatally via complicated signal effectors, which may have negative impact on meat quality simultaneously.


Asunto(s)
Regulación del Desarrollo de la Expresión Génica , Factor I del Crecimiento Similar a la Insulina/genética , Músculo Esquelético/crecimiento & desarrollo , Músculo Esquelético/metabolismo , Transducción de Señal/genética , Sus scrofa/crecimiento & desarrollo , Sus scrofa/genética , Animales , Animales Recién Nacidos , Cruzamiento , China , Factor I del Crecimiento Similar a la Insulina/metabolismo
14.
Comp Biochem Physiol B Biochem Mol Biol ; 151(2): 159-66, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18638563

RESUMEN

AMPD1 is the muscle-specific form of the AMPD multigene families in mammals and plays an important role in the purine nucleotide cycle and energy metabolism in skeletal muscle. In this study, we cloned and characterized AMPD1 from Sus scrofa muscle. The promoter of porcine AMPD1 contained several putative muscle-specific transcription factor binding sites (E box, myogenin, MEF2, Spl-CTF/NF-l), one RORalpha2 binding motif and NF-kappaB site. The deduced amino acid sequence of porcine AMPD1 contains an AMP deaminase signature sequence (SLSTDDP). RT-PCR analyses showed that AMPD1 was expressed specifically in skeletal muscle. Expression of AMPD1 was up-regulated during the muscle development and was higher in Yorkshire than in Meishan pigs. AMPD1 gene was expressed at higher levels in longissimus dorsi and bicepsfemoris muscles compared with soleus and masseter muscles in both Yorkshire and Meishan pigs. Moreover, we found that a single nucleotide polymorphism (SNP, T/C(426)) in exon12 of the AMPD1 gene was significantly associated with loin muscle area trait (p<0.01), loin muscle height (p<0.01) and average backfat thickness (p<0.05). This result suggests that the AMPD1 gene might be a candidate gene of meat production trait and provides useful information for further studies on its roles in porcine skeletal muscle.


Asunto(s)
AMP Desaminasa/genética , Músculo Esquelético/enzimología , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Sitios de Unión/genética , Clonación Molecular , Cartilla de ADN/genética , Femenino , Regulación del Desarrollo de la Expresión Génica , Regulación Enzimológica de la Expresión Génica , Datos de Secuencia Molecular , Músculo Esquelético/crecimiento & desarrollo , Polimorfismo de Nucleótido Simple , Embarazo , Regiones Promotoras Genéticas , Homología de Secuencia de Aminoácido , Especificidad de la Especie , Sus scrofa , Distribución Tisular
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