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1.
Nucleic Acids Res ; 52(9): 4906-4921, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38407438

RESUMEN

Eukaryotic genomes are spatially organized within the nucleus in a nonrandom manner. However, fungal genome arrangement and its function in development and adaptation remain largely unexplored. Here, we show that the high-order chromosome structure of Fusarium graminearum is sculpted by both H3K27me3 modification and ancient genome rearrangements. Active secondary metabolic gene clusters form a structure resembling chromatin jets. We demonstrate that these jet-like domains, which can propagate symmetrically for 54 kb, are prevalent in the genome and correlate with active gene transcription and histone acetylation. Deletion of GCN5, which encodes a core and functionally conserved histone acetyltransferase, blocks the formation of the domains. Insertion of an exogenous gene within the jet-like domain significantly augments its transcription. These findings uncover an interesting link between alterations in chromatin structure and the activation of fungal secondary metabolism, which could be a general mechanism for fungi to rapidly respond to environmental cues, and highlight the utility of leveraging three-dimensional genome organization in improving gene transcription in eukaryotes.


Asunto(s)
Cromatina , Cromosomas Fúngicos , Fusarium , Metabolismo Secundario , Acetilación , Cromatina/metabolismo , Cromatina/genética , Cromosomas Fúngicos/genética , Cromosomas Fúngicos/metabolismo , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Fusarium/genética , Fusarium/metabolismo , Regulación Fúngica de la Expresión Génica , Genoma Fúngico , Histona Acetiltransferasas/metabolismo , Histona Acetiltransferasas/genética , Histonas/metabolismo , Histonas/genética , Familia de Multigenes , Metabolismo Secundario/genética , Transcripción Genética
2.
Plant Biotechnol J ; 22(7): 2033-2050, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38408119

RESUMEN

Although forward-genetics-metabolomics methods such as mGWAS and mQTL have proven effective in providing myriad loci affecting metabolite contents, they are somehow constrained by their respective constitutional flaws such as the hidden population structure for GWAS and insufficient recombinant rate for QTL. Here, the combination of mGWAS and mQTL was performed, conveying an improved statistical power to investigate the flavonoid pathways in common wheat. A total of 941 and 289 loci were, respectively, generated from mGWAS and mQTL, within which 13 of them were co-mapped using both approaches. Subsequently, the mGWAS or mQTL outputs alone and their combination were, respectively, utilized to delineate the metabolic routes. Using this approach, we identified two MYB transcription factor encoding genes and five structural genes, and the flavonoid pathway in wheat was accordingly updated. Moreover, we have discovered some rare-activity-exhibiting flavonoid glycosyl- and methyl-transferases, which may possess unique biological significance, and harnessing these novel catalytic capabilities provides potentially new breeding directions. Collectively, we propose our survey illustrates that the forward-genetics-metabolomics approaches including multiple populations with high density markers could be more frequently applied for delineating metabolic pathways in common wheat, which will ultimately contribute to metabolomics-assisted wheat crop improvement.


Asunto(s)
Flavonoides , Sitios de Carácter Cuantitativo , Triticum , Triticum/genética , Triticum/metabolismo , Triticum/enzimología , Flavonoides/metabolismo , Sitios de Carácter Cuantitativo/genética , Mapeo Cromosómico , Metabolómica/métodos , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
3.
J Transl Med ; 22(1): 164, 2024 02 16.
Artículo en Inglés | MEDLINE | ID: mdl-38365806

RESUMEN

BACKGROUND: Pulmonary arterial hypertension (PAH) is a severe cardiopulmonary disease characterized by complement dependent and proinflammatory activation of macrophages. However, effective treatment for complement activation in PAH is lacking. We aimed to explore the effect and mechanism of CP40-KK (a newly identified analog of selective complement C3 inhibitor CP40) in the PAH model. METHODS: We used western blotting, immunohistochemistry, and immunofluorescence staining of lung tissues from the monocrotaline (MCT)-induced rat PAH model to study macrophage infiltration, NLPR3 inflammasome activation, and proinflammatory cytokines (IL-1ß and IL-18) release. Surface plasmon resonance (SPR), ELISA, and CH50 assays were used to test the affinity between CP40-KK and rat/human complement C3. CP40-KK group rats only received CP40-KK (2 mg/kg) by subcutaneous injection at day 15 to day 28 continuously. RESULTS: C3a was significantly upregulated in the plasma of MCT-treated rats. SPR, ELISA, and CH50 assays revealed that CP40-KK displayed similar affinity binding to human and rat complement C3. Pharmacological inhibition of complement C3 cleavage (CP40-KK) could ameliorate MCT-induced NLRP3 inflammasome activity, pulmonary vascular remodeling, and right ventricular hypertrophy. Mechanistically, increased proliferation of pulmonary arterial smooth muscle cells is closely associated with macrophage infiltration, NLPR3 inflammasome activation, and proinflammatory cytokines (IL-1ß and IL-18) release. Besides, C3a enhanced IL-1ß activity in macrophages and promoted pulmonary arterial smooth muscle cell proliferation in vitro. CONCLUSION: Our findings suggest that CP40-KK treatment was protective in the MCT-induced rat PAH model, which might serve as a therapeutic option for PAH.


Asunto(s)
Hipertensión Pulmonar , Hipertensión Arterial Pulmonar , Ratas , Humanos , Animales , Hipertensión Arterial Pulmonar/tratamiento farmacológico , Inflamasomas/metabolismo , Interleucina-18/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Complemento C3/metabolismo , Inactivadores del Complemento/efectos adversos , Inactivadores del Complemento/metabolismo , Arteria Pulmonar/metabolismo , Citocinas/metabolismo , Modelos Animales de Enfermedad
4.
BMC Neurol ; 24(1): 273, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39103783

RESUMEN

BACKGROUND: Fifteen-and-a-Half Syndrome is an uncommon clinical presentation characterized by the coexistence of one-and-a-half syndrome and bilateral facial palsy. In this study, we provide a comprehensive description of symptom evolution and imaging changes in a patient with Fifteen-and-a-Half Syndrome. CASE PRESENTATION: A 54-year-old male presented with sudden onset of one-and-a-half syndrome, which gradually progressed to fifteen-and-a-half syndrome. The final diagnosis was confirmed to be pontine infarction which occurred at the midline of the pontine tegmentum. CONCLUSION: This case highlights the diverse and progressive early clinical manifestations associated with Fifteen-and-a-half Syndrome. Currently, all reported cases of this syndrome are linked to brainstem infarction; however, early differential diagnosis is crucial to ensure prompt initiation of appropriate treatment for affected patients.


Asunto(s)
Infartos del Tronco Encefálico , Parálisis Facial , Humanos , Masculino , Persona de Mediana Edad , Parálisis Facial/diagnóstico , Parálisis Facial/diagnóstico por imagen , Parálisis Facial/etiología , Infartos del Tronco Encefálico/diagnóstico por imagen , Infartos del Tronco Encefálico/complicaciones , Infartos del Tronco Encefálico/diagnóstico , Síndrome , Imagen por Resonancia Magnética/métodos , Tegmento Pontino/diagnóstico por imagen
5.
Pestic Biochem Physiol ; 200: 105815, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38582573

RESUMEN

Fusarium graminearum is an important fungal pathogen causing Fusarium head blight (FHB) in wheat and other cereal crops worldwide. Due to lack of resistant wheat cultivars, FHB control mainly relies on application of chemical fungicides. Both fludioxonil (a phenylpyrrole compound) and phenamacril (a cyanoacrylate fungicide) have been registered for controlling FHB in China, however, fludioxonil-resistant isolates of F. graminearum have been detected in field. To evaluate the potential risk of dual resistance of F. graminearum to both compounds, fludioxonil and phenamacril dual resistant (DR) mutants of F. graminearum were obtained via fungicide domestication in laboratory. Result showed that resistance of the DR mutants to both fludioxonil and phenamacril were genetically stable after sub-cultured for ten generations or stored at 4 °C for 30 days on fungicide-free PDA. Cross-resistance assay showed that the DR mutants remain sensitive to other groups of fungicides, including carbendazim, tebuconazole, pydiflumetofen, and fluazinam. In addition, the DR mutants exhibited defects in mycelia growth, conidiation, mycotoxin deoxynivalenol (DON) production, and virulence Moreover, the DR mutants displayed increased sensitivity to osmotic stress. Sequencing results showed that amino acid point mutations S217L/T in the myosin I protein is responsible for phenamacril resistance in the DR mutants. Our results indicate that mutations leading to fludioxonil and phenamacril dual resistance could result in fitness cost for F. graminearum. Our results also suggest that the potential risk of F. graminearum developing resistance to both fludioxonil and phenamacril in field could be rather low, which provides scientific guidance in controlling FHB with fludioxonil and phenamacril.


Asunto(s)
Dioxoles , Fungicidas Industriales , Fusarium , Pirroles , Fungicidas Industriales/farmacología , Farmacorresistencia Fúngica/genética , Cianoacrilatos , Enfermedades de las Plantas/microbiología
6.
J Gene Med ; 25(8): e3510, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36998238

RESUMEN

BACKGROUND: Osteoarthritis (OA) is a prevalent degenerative articular disease for which there is no effective treatment. Progress has been made in mesenchymal stem cell (MSC)-based therapy in OA, and the efficacy has been demonstrated to be a result of paracrine exosomes from MSCs. Decellularized extracellular matrix (dECM) provides an optimum microenvironment for the expansion of MSCs. In the present study, we aimed to investigate whether exosomes isolated from bone marrow mesenchymal stem cells (BMSCs) with dECM pretreatment (dECM-BMSC-Exos) enhance the amelioration of OA. METHODS: Exosomes from BMSCs with or without dECM pretreatment were isolated. We measured and compared the effect of the BMSC-Exo and dECM-BMSC-Exo on interleukin (IL)-1ß-induced chondrocytes by analyzing proliferation, anabolism and catabolism, migration and apoptosis in vitro. The in vivo experiment was performed by articular injection of exosomes into DMM mice, followed by histological evaluation of cartilage. MicroRNA sequencing of exosomes was performed on BMSC-Exo and dECM-BMSC-Exo to investigate the underlying mechanism. The function of miR-3473b was validated by rescue studies in vitro and in vivo using antagomir-3473b. RESULTS: IL-1ß-treated chondrocytes treated with dECM-BMSC-Exos showed enhanced proliferation, anabolism, migration and anti-apoptosis properties compared to BMSC-Exos. DMM mice injected with dECM-BMSC-Exo showed better cartilage regeneration than those injected with BMSC-Exo. Interestingly, miR-3473b was significantly elevated in dECM-BMSC-Exos and was found to mediate the protective effect in chondrocytes by targeting phosphatase and tensin homolog (PTEN), which activated the PTEN/AKT signaling pathway. CONCLUSIONS: dECM-BMSC-Exo can enhance the alleviation of osteoarthritis via promoting migration, improving anabolism and inhibiting apoptosis of chondrocytes by upregulating miR-3473b, which targets PTEN.


Asunto(s)
Exosomas , Células Madre Mesenquimatosas , MicroARNs , Osteoartritis , Ratones , Animales , MicroARNs/genética , MicroARNs/metabolismo , Matriz Extracelular Descelularizada , Tensinas/metabolismo , Exosomas/genética , Exosomas/metabolismo , Exosomas/patología , Osteoartritis/genética , Osteoartritis/terapia , Osteoartritis/metabolismo , Células Madre Mesenquimatosas/metabolismo
7.
New Phytol ; 240(6): 2455-2467, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37799006

RESUMEN

The conserved Spt-Ada-Gcn5-Acetyltransferase (SAGA) complex controls eukaryotic transcription by modifying acetylation of histones. However, the mechanisms for this complex in regulating the transcription of target-specific genes remain largely unknown in phytopathogenic fungi. A filamentous fungal-specific transcription factor FgStuA was identified to interact with the SAGA complex physically. The coordinative mechanisms of FgStuA with the SAGA complex in regulating secondary metabolism and virulence were investigated in Fusarium graminearum with genetic, biochemical and molecular techniques. The transcription factor FgStuA binds to a 7-bp cis-element (BVTGCAK) of its target gene promoter. Under mycotoxin deoxynivalenol (DON) induction conditions, FgStuA recruits the SAGA complex into the promoter of TRI6, a core regulator of the DON biosynthesis gene cluster, leading to enhanced transcription of TRI6. During this process, we found that FgStuA is subject to acetylation by the SAGA complex, and acetylation of FgStuA plays a critical role for its enrichment in the TRI6 promoter. In addition, FgStuA together with the SAGA complex modulates fungal virulence. This study uncovers a novel regulatory mechanism of a transcription factor, which recruits and interacts with the SAGA complex to activate specific gene expression in pathogenic fungi.


Asunto(s)
Fusarium , Micotoxinas , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Metabolismo Secundario , Virulencia , Micotoxinas/metabolismo , Hongos/metabolismo
8.
J Pineal Res ; 74(2): e12841, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36396897

RESUMEN

Melatonin (Mel) is a multifunctional biomolecule found in both animals and plants. In plants, the biosynthesis of Mel from tryptophan (Trp) has been delineated to comprise of four consecutive reactions. However, while the genes encoding these enzymes in rice are well characterized no systematic evaluation of the overall pathway has, as yet, been published for wheat. In the current study, the relative contents of six Mel-pathway-intermediates including Trp, tryptamine (Trm), serotonin (Ser), 5-methoxy tryptamine (5M-Trm), N-acetyl serotonin (NAS) and Mel, were determined in 24 independent tissues spanning the lifetime of wheat. These studies indicated that Trp was the most abundant among the six metabolites, followed by Trm and Ser. Next, the candidate genes expressing key enzymes involved in the Mel pathway were explored by means of metabolite-based genome-wide association study (mGWAS), wherein two TDC genes, a T5H gene and one SNAT gene were identified as being important for the accumulation of Mel pathway metabolites. Moreover, a 463-bp insertion within the T5H gene was discovered that may be responsible for variation in Ser content. Finally, a ASMT gene was found via sequence alignment against its rice homolog. Validations of these candidate genes were performed by in vitro enzymatic reactions using proteins purified following recombinant expression in Escherichia coli, transient gene expression in tobacco, and transgenic approaches in wheat. Our results thus provide the first comprehensive investigation into the Mel pathway metabolites, and a swift candidate gene identification via forward-genetics strategies, in common wheat.


Asunto(s)
Melatonina , Animales , Melatonina/metabolismo , Triticum/genética , Triticum/metabolismo , Serotonina/metabolismo , Estudio de Asociación del Genoma Completo , Triptaminas , Plantas/metabolismo , Triptófano/metabolismo
9.
Phytopathology ; 113(5): 771-785, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36324059

RESUMEN

Disease resistance improvement remains a major focus in breeding programs as diseases continue to devastate Brassica production systems due to intensive cultivation and climate change. Genomics has paved the way to understand the complex genomes of Brassicas, which has been pivotal in the dissection of the genetic underpinnings of agronomic traits driving the development of superior cultivars. The new era of genomics-assisted disease resistance breeding has been marked by the development of high-quality genome references, accelerating the identification of disease resistance genes controlling both qualitative (major) gene and quantitative resistance. This facilitates the development of molecular markers for marker assisted selection and enables genome editing approaches for targeted gene manipulation to enhance the genetic value of disease resistance traits. This review summarizes the key advances in the development of genomic resources for Brassica species, focusing on improved genome references, based on long-read sequencing technologies and pangenome assemblies. This is further supported by the advances in pathogen genomics, which have resulted in the discovery of pathogenicity factors, complementing the mining of disease resistance genes in the host. Recognizing the co-evolutionary arms race between the host and pathogen, it is critical to identify novel resistance genes using crop wild relatives and synthetic cultivars or through genetic manipulation via genome-editing to sustain the development of superior cultivars. Integrating these key advances with new breeding techniques and improved phenotyping using advanced data analysis platforms will make disease resistance improvement in Brassica species more efficient and responsive to current and future demands.


Asunto(s)
Brassica , Brassica/genética , Resistencia a la Enfermedad/genética , Genoma de Planta/genética , Enfermedades de las Plantas/genética , Fitomejoramiento , Genómica
10.
BMC Anesthesiol ; 23(1): 288, 2023 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-37620761

RESUMEN

BACKGROUND: Hypotension frequently occurs after spinal anesthesia during cesarean delivery, and fluid loading is recommended for its prevention. We evaluated the efficacy of subclavian vein (SCV) ultrasound (US)-guided volume optimization in preventing hypotension after spinal anesthesia during cesarean delivery. METHODS: This randomized controlled study included 80 consecutive full-term parturients scheduled for cesarean delivery under spinal anesthesia. The women were randomly divided into the SCVUS group, with SCVUS analysis before spinal anesthesia with SCVUS-guided volume management, and the control group without SCVUS assessment. The SCVUS group received 3 mL/kg crystalloid fluid challenges repeatedly within 3 min with a 1-min interval based on the SCV collapsibility index (SCVCI), while the control group received a fixed dose (10 mL/kg). Incidence of post-spinal anesthetic hypotension was the primary outcome. Total fluid volume, vasopressor dosage, changes in hemodynamic parameters, maternal adverse effects, and neonatal status were secondary outcomes. RESULTS: The total fluid volume was significantly higher in the control group than in the SCVUS group (690 [650-757.5] vs. 160 [80-360] mL, p < 0.001), while the phenylephrine dose (0 [0-40] vs. 0 [0-30] µg, p = 0.276) and incidence of post-spinal anesthetic hypotension (65% vs. 60%, p = 0.950) were comparable between both the groups. The incidence of maternal adverse effects, including nausea/vomiting and bradycardia (12.5% vs. 17.5%, p = 0.531 and 7.5% vs. 5%, p = 1.00, respectively), and neonatal outcomes (Apgar scores) were comparable between the groups. SCVCI correlated with the amount of fluid administered (R = 0.885, p < 0.001). CONCLUSIONS: SCVUS-guided volume management did not ameliorate post-spinal anesthetic hypotension but reduced the volume of the preload required before spinal anesthesia. Reducing preload volume did not increase the incidence of maternal and neonatal adverse effects nor did it increase the total vasopressor dose. Moreover, reducing preload volume could relieve the heart burden of parturients, which has high clinical significance. CLINICAL TRIAL REGISTRATION: The trial was registered with the Chinese Clinical Trial Registry at chictr.org.cn (registration number, ChiCTR2100055050) on December 31, 2021.


Asunto(s)
Anestesia Raquidea , Anestésicos , Hipotensión , Embarazo , Recién Nacido , Femenino , Humanos , Vena Subclavia/diagnóstico por imagen , Anestesia Raquidea/efectos adversos , Hipotensión/etiología , Hipotensión/prevención & control , Ultrasonografía Intervencional
11.
Aging Clin Exp Res ; 35(11): 2531-2542, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37656410

RESUMEN

BACKGROUND: Long-term nursing home (NH) care helps NH residents with their daily activities and improves their quality of life, but negatively affects their independent physical activities and increases the risk of dangerous events. Dangerous events in the elderly usually occur in the conversion of walking periods when forward striding has already happened, but the body has not yet entered a completely steady walking. OBJECTIVES: Compare the gait characteristics in Chinese long-term NH residents and community-living elderly during the walking Transitional Period (TP) and Stabilization Period (SP). METHODS: 32 long-term NH residents and 33 age- and sex-matched community-living elderly were recruited. The 30-Second Chair Stand Test (30-s CST), Timed Up and Go Test (TUGT), and Modified Falls Efficacy Scale (MFES) were used to assess their body function. The Xsens MVN BIOMECH system was used to collect and analyze the gait parameters of participants. RESULTS: Compared to community-living elderly, NH residents had fewer numbers of 30-s CST, took more time to complete TUGT, and lower MEFS scores. NH residents showed slower gait speed (P < 0.001), less peak hip flexion (P = 0.022) and extension (P = 0.003), knee internal rotation (P = 0.023), and ankle plantarflexion (P = 0.001) and internal rotation (P = 0.007) angles during walking. When walking progressed from TP to SP, NH residents showed increased ankle dorsiflexion (P < 0.001), decreased hip internal rotation (P < 0.001), and community-living elderly had increased hip extension (P = 0.005) angles. CONCLUSIONS: Chinese long-term NH residents had reduced lower extremities strength and postural balance, and higher fear of falling compared to community-living elderly. Their walking performance also showed high fall risk. Besides, long-term NH residents adopted a distal strategy to propel the body forward, which may be a compensatory measure to compensate for inadequate proximal joint control from forward walking to stable walking, and long-term NH residents have reduced postural stability during this process.


Asunto(s)
Calidad de Vida , Caminata , Anciano , Humanos , Fenómenos Biomecánicos , Pueblos del Este de Asia , Miedo , Casas de Salud , Equilibrio Postural , Estudios de Tiempo y Movimiento , Caminata/fisiología , Caminata/psicología , Vida Independiente , Características de la Residencia
12.
Acta Biochim Biophys Sin (Shanghai) ; 55(9): 1425-1433, 2023 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-37525533

RESUMEN

Chondrocyte senescence is an important mechanism underlying osteoarthritis in the senile population and is characterized by reduced expressions of the extracellular matrix proteins. The involvement of glycolysis and the tricarboxylic acid cycle in the development of osteoarthritis is inclusive. The present study aims to investigate the role of the glycolytic enzyme M2 isoform of pyruvate kinase (PKM2) in chondrocytes in senescence and inflammation. Primary chondrocytes are isolated from the knee joints of neonatal mice. Small interfering RNAs (siRNAs) against PKM2 are transfected using lipofectamine. RNA sequencing is conducted in primary chondrocytes with the PKM2 gene deleted. Cell apoptosis, autophagy, reactive oxygen species measurement, and senescent conditions are examined. The glycolytic rate in cells is measured by Seahorse examination. Interleukin 1-ß (IL-1ß) increases the protein expressions of matrix metallopeptidases (MMP)13 and PKM2 and reduces the protein expression of collagen type II (COL2A1) in primary chondrocytes. Silencing of PKM2 alters the protein expressions of MMP13, PKM2, and COL2A1 in the same pattern in quiescent and stimulated chondrocytes. RNA sequencing analysis reveals that PKM2 silencing reduces senescent biomarker p16 INK4a expression. Compared with low-passage chondrocytes, high-passage chondrocytes exhibit increased expression of p16 INK4a and reduced expression of COL2A1. Silencing of PKM2 reduces SA-ß-Gal signals and increases COL2A1 expression in high-passage chondrocytes. Seahorse assay reveals that PKM2 deletion favors the tricarboxylic acid cycle in mitochondria in low- but not in high-passage chondrocytes. In summary, the glycolytic enzyme PMK2 modulates chondrocyte senescence but does not participate in the regulation of inflammation.


Asunto(s)
Osteoartritis , Animales , Ratones , Senescencia Celular/genética , Condrocitos/metabolismo , Inhibidor p16 de la Quinasa Dependiente de Ciclina/genética , Glucólisis , Inflamación/genética , Inflamación/metabolismo , Interleucina-1beta/metabolismo , Osteoartritis/genética , Osteoartritis/metabolismo , ARN Interferente Pequeño/metabolismo
13.
J Am Chem Soc ; 143(4): 1924-1931, 2021 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-33471527

RESUMEN

Carbon-halogen reductive elimination is a conceptually novel elementary reaction. Its emergence broadens the horizons of transition-metal catalysis and provides new access to organohalides of versatile synthetic value. However, as the reverse process of facile oxidative addition of Pd(0) to organohalide, carbon-halogen reductive elimination remains elusive and practically difficult. Overcoming the thermodynamic disfavor inherent to such an elementary reaction is frustrated by the high reaction temperature and requirement of distinctive ligands. Here, we report a general strategy that employs [Et3NH]+[BF4]- as an H-bond donor under a toluene/water/(CH2OH)2 biphasic system to efficiently promote C(sp3)-halogen reductive elimination at low temperature. This enables a series of Pd(0)-catalyzed carbohalogenation reactions, including more challenging and unprecedented asymmetric carbobromination with a high level of efficiency and enantioselectivity by using readily available ligands. Mechanistic studies suggest that [Et3NH]+[BF4]- can facilitate the heterolytic dissociation of halogen-PdIIC(sp3) bonds via a potential H-bonding interaction to reduce the energy barrier of C(sp3)-halogen reductive elimination, thereby rendering it feasible in an SN2 manner.

14.
J Exp Bot ; 72(2): 268-282, 2021 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-33005935

RESUMEN

Seeds are complex biological systems comprising three genetically distinct tissues: embryo, endosperm, and maternal tissues (including seed coats and pericarp) nested inside one another. Cereal grains represent a special type of seeds, with the largest part formed by the endosperm, a specialized triploid tissue ensuring embryo protection and nourishment. We investigated dynamic changes in DNA content in three of the major seed tissues from the time of pollination up to the dry seed. We show that the cell cycle is under strict developmental control in different seed compartments. After an initial wave of active cell division, cells switch to endocycle and most endoreduplication events are observed in the endosperm and seed maternal tissues. Using different barley cultivars, we show that there is natural variation in the kinetics of this process. During the terminal stages of seed development, specific and selective loss of endoreduplicated nuclei occurs in the endosperm. This is accompanied by reduced stability of the nuclear genome, progressive loss of cell viability, and finally programmed cell death. In summary, our study shows that endopolyploidization and cell death are linked phenomena that frame barley grain development.


Asunto(s)
Hordeum , Ciclo Celular , Endorreduplicación , Endospermo/genética , Hordeum/genética , Semillas/genética
15.
Int J Mol Sci ; 22(9)2021 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-34065108

RESUMEN

Nonalcoholic fatty liver disease (NAFLD) is strongly linked to the global epidemic of obesity and type 2 diabetes mellitus (T2DM). Notably, NAFLD can progress from the mildest form of simple steatosis to nonalcoholic steatohepatitis (NASH) that increases the risk for hepatocellular carcinoma (HCC), which is a malignancy with a dismal prognosis and rising incidence in the United States and other developed counties, possibly due to the epidemic of NAFLD. Metformin, the first-line drug for T2DM, has been suggested to reduce risks for several types of cancers including HCC and protect against NASH-related HCC, as revealed by epidemical studies on humans and preclinical studies on animal models. This review focuses on the pathogenesis of NASH-related HCC and the mechanisms by which metformin inhibits the initiation and progression of NASH-related HCC. Since the functional role of immune cells in liver homeostasis and pathogenesis is increasingly appreciated in developing anti-cancer therapies on liver malignancies, we discuss both the traditional targets of metformin in hepatocytes and the recently defined effects of metformin on immune cells.


Asunto(s)
Hipoglucemiantes/farmacología , Hígado/efectos de los fármacos , Hígado/metabolismo , Metformina/farmacología , Animales , Carcinoma Hepatocelular/etiología , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/prevención & control , Daño del ADN , Progresión de la Enfermedad , Susceptibilidad a Enfermedades , Hepatocitos/efectos de los fármacos , Hepatocitos/metabolismo , Humanos , Neoplasias Hepáticas/etiología , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/prevención & control , Macrófagos/metabolismo , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Enfermedad del Hígado Graso no Alcohólico/etiología , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/patología , Estrés Oxidativo , Sustancias Protectoras/farmacología , Factores de Riesgo
16.
J Anesth ; 35(4): 475-482, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34050798

RESUMEN

PURPOSE: Recently, a new handheld ultrasound-based device, called Accuro, has been commercialized with a real-time automated interpretation of lumbar ultrasound images. We hypothesized that the handheld ultrasound device would improve the efficacy and safety of combined spinal-epidural anesthesia (CSEA) for cesarean delivery in obese parturients. METHODS: Eighty parturients with a body mass index > 30 kg∙m-2 scheduled for elective cesarean delivery were randomly allocated equally (palpation group and ultrasound group). The primary outcome was the first insertion success rate. Secondary outcomes were the time taken to identify the needle puncture site, duration of CSEA procedure, the total time, the rate of parturients who require needle redirections, the number of skin punctures, changes in the intended interspace, and the incidence of complications. RESULTS: Compared to the palpation group, the first insertion success rate was significantly higher (72.5% vs. 40.0%; P = 0.003), and time taken to identify the needle puncture site was less (30 [26-36] vs. 39 [32-49] seconds; P = 0.001) in the ultrasound group. The rate of parturients who required needle redirections (40.0% vs. 72.5%; P = 0.003) and the incidence of paresthesia were both lower (7.5% vs. 45.0%; P < 0.001). The other outcomes had no significant difference between groups. The mean difference between the epidural depth measured by the handheld ultrasound and needle depth was - 0.29 cm [95% limit of agreement, - 0.52 to - 0.05]. CONCLUSIONS: Our study suggests using the Accuro ultrasound device can enhance the efficacy and safety of CSEA in obese parturients when executed by experienced anesthesiologists, and its automated estimation of epidural depth is accurate.


Asunto(s)
Anestesia Epidural , Anestesia Obstétrica , Anestesia Raquidea , Anestesia Epidural/efectos adversos , Computadores , Espacio Epidural/diagnóstico por imagen , Femenino , Humanos , Obesidad/complicaciones , Palpación , Embarazo , Ultrasonografía Intervencional
17.
Can J Neurol Sci ; 47(2): 226-230, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31806074

RESUMEN

BACKGROUND: Identifying risk factors and mortality of individuals with Alzheimer's disease (AD) could have important implications for the clinical management of AD. OBJECTIVE: This pilot study aimed to examine the overall mortality of AD patients over a 10-year surveillance period in Shanghai, China. This study is an extension of our previous investigation on mortality of neurodegenerative diseases. METHODS: One hundred and thirty-two AD patients recruited from the memory clinics of two hospitals in Shanghai in 2007 were followed up until December 31, 2017 or death, representing a follow-up period of up to 10 years. Overall standardized mortality ratios (SMRs) were calculated, and predictors for survival at recruitment were estimated. RESULTS: Sixty-seven patients had died by December 31, 2017, and the SMR at 10 years of follow-up was 1.225 (95% confidence interval 0.944-1.563). Employing Cox's proportional hazard modeling, lower Mini-Mental State Examination score, and comorbid diabetes predicted poor survival in this cohort. CONCLUSION: This pilot study suggests a similar survival trend of patients with AD compared to the general population in Shanghai urban region. Poor cognitive status and comorbid diabetes had a negative impact on the survival of AD patients.


Asunto(s)
Enfermedad de Alzheimer/fisiopatología , Diabetes Mellitus Tipo 2/epidemiología , Mortalidad , Actividades Cotidianas , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/epidemiología , China/epidemiología , Estudios de Cohortes , Comorbilidad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Pruebas de Estado Mental y Demencia , Persona de Mediana Edad , Proyectos Piloto , Modelos de Riesgos Proporcionales , Factores de Riesgo
18.
Cell Biochem Funct ; 38(7): 895-904, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32064636

RESUMEN

Long noncoding RNAs have been proved in regulating tumourigenesis, including hepatocellular carcinoma (HCC). However, up to date, the role of PCAT6 in HCC is rare to be reported. In current study, bioinformatics analysis and quantitative real-time PCR were applied to examine the expression of PCAT6 in HCC. The role of PCAT6 in cell proliferation, cell cycle arrest, apoptosis, and metastasis were detected in both gain- and loss-of-function studies by cell biological assays. Bioinformatics analysis was employed to investigate the PCAT6-related genes and pathways in HCC. And we found that PCAT6 was significantly upregulated in HCC tissues and correlated with poor overall survival and disease-free survival in HCC patients. Furthermore, elevated PCAT6 promoted cell proliferation, inhibited cell cycle arrest and cell apoptosis while deficiency of PCAT6 impaired cell proliferation, caused cell cycle arrest and induced cell apoptosis of HCC. Moreover, as for bioinformatics analysis, a total of 389 PCAT6-related genes were found in both HCC tissue and cell lines, and these promising target genes were highly enriched in various key pathways, such as Wnt, HIF-1 signalling pathway, and metabolic pathways. Additionally, among these genes, DCAF13, SNRPB2, RPS8, and FKBP1A were revealed to be overexpressed in HCC and predicted poor prognosis. Taken together, our findings illustrate that PCAT6 contributes to HCC progression and might be a potential target for HCC therapy. Bioinformatics analysis may present a new way for assessing the underlying mechanism of PCAT6 in HCC. SIGNIFICANCE OF THE STUDY: Hepatocellular carcinoma (HCC) is one of the most common and malignant tumours all over the world. In this study, we observed that PCAT6 was upregulated in HCC and correlated with poor prognosis of HCC patients. PCAT6 could promote cell proliferation, inhibit cell cycle arrest and cell apoptosis of HCC, suggesting PCAT6 exerts tumorigenic role in HCC. Moreover, bioinformatics analysis revealed a total of 389 PCAT6-related genes in both HCC tissue and cell lines, and these promising target genes were highly enriched in various key pathways, such as Wnt, HIF-1 signalling pathway, and metabolic pathways. These finding provided evidence that PACT6 may be identified as a strategy to treat HCC in the future.


Asunto(s)
Apoptosis , Carcinoma Hepatocelular/patología , Puntos de Control del Ciclo Celular , Neoplasias Hepáticas/patología , ARN Largo no Codificante/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/mortalidad , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Supervivencia sin Enfermedad , Humanos , Estimación de Kaplan-Meier , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/mortalidad , Pronóstico , Mapas de Interacción de Proteínas/genética , Interferencia de ARN , ARN Interferente Pequeño/metabolismo , Regulación hacia Arriba
19.
Mar Drugs ; 18(4)2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-32244721

RESUMEN

Cold-adapted alginate lyases have unique advantages for alginate oligosaccharide (AOS) preparation and brown seaweed processing. Robust and cold-adapted alginate lyases are urgently needed for industrial applications. In this study, a cold-adapted alginate lyase-producing strain Vibrio sp. W2 was screened. Then, the gene ALYW201 was cloned from Vibrio sp. W2 and expressed in a food-grade host, Yarrowia lipolytica. The secreted Alyw201 showed the activity of 64.2 U/mL, with a molecular weight of approximate 38.0 kDa, and a specific activity of 876.4 U/mg. Alyw201 performed the highest activity at 30 °C, and more than 80% activity at 25-40 °C. Furthermore, more than 70% of the activity was obtained in a broad pH range of 5.0-10.0. Alyw201 was also NaCl-independent and salt-tolerant. The degraded product was that of the oligosaccharides of DP (Degree of polymerization) 2-6. Due to its robustness and its unique pH-stable property, Alyw201 can be an efficient tool for industrial production.


Asunto(s)
Alginatos/metabolismo , Proteínas Bacterianas/metabolismo , Polisacárido Liasas/metabolismo , Vibrio/enzimología , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Clonación Molecular , Frío/efectos adversos , Pruebas de Enzimas , Estabilidad de Enzimas , Concentración de Iones de Hidrógeno , Microbiología Industrial , Peso Molecular , Oligosacáridos/metabolismo , Phaeophyceae/química , Polisacárido Liasas/química , Polisacárido Liasas/genética , Algas Marinas/química , Especificidad por Sustrato , Vibrio/genética , Yarrowia/genética
20.
Ecotoxicol Environ Saf ; 190: 110148, 2020 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-31911388

RESUMEN

Phthalate esters have raised public concerns owing to their effects on the environment and human health. We identified a novel phthalate-degrading hydrolase, EstJ6, from a metagenomic library using function-driven screening. Phylogenetic analysis indicated that EstJ6 is a member of family IV esterases. EstJ6 hydrolyzed various dialkyl and monoalkyl phthalate esters, and exhibited high hydrolytic activity (128 U/mg) toward dibutyl phthalate at 40 °C and pH 7.5. EstJ6 hydrolyzed not only common phthalate esters with simple side chains but also diethylhexyl phthalate and monoethylhexyl phthalate, which have complex and long side chains. Site-directed mutagenesis indicated that the catalytic triad residues of EstJ6 consists of Ser146, Glu240, and His270. EstJ6 is therefore a promising biodegradation enzyme, and our study illustrates the advantages of a metagenomic approach in identifying enzyme-coding genes for agricultural, food, and biotechnological applications.


Asunto(s)
Biodegradación Ambiental , Hidrolasas/metabolismo , Ácidos Ftálicos/metabolismo , Dibutil Ftalato/metabolismo , Dietilhexil Ftalato/metabolismo , Esterasas/metabolismo , Ésteres/química , Biblioteca de Genes , Hidrolasas/genética , Hidrólisis , Metagenoma , Filogenia , Suelo
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