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1.
J Immunol ; 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39248593

RESUMEN

IgG autoantibodies to heat shock protein 70 (HSP70) are found in many immune-mediated clinical syndromes, and their presence among patients with idiopathic pulmonary fibrosis (IPF) portends especially poor outcomes. However, pathological effects of IPF anti-HSP70 have not been studied extensively. IPF lung fibroblasts are apoptosis resistant, and this dysregulation contributes to the accumulation of fibroblasts that characterizes the disease. During stress, HSP70 protein is exported extracellularly, where it binds to cognate cell surface receptors that mediate a variety of functional effects, including apoptosis inhibition. We hypothesized anti-HSP70 could engage HSP70-receptor complexes on fibroblasts that alter their apoptosis susceptibility. We found HSP70 is ubiquitously expressed on primary human lung fibroblasts. Treatment with anti-HSP70 isolated from patients with IPF with acute exacerbations increased Bcl-2 expression in human lung fibroblasts and reduced their susceptibility to staurosporine-induced apoptosis. Chromatin immunoprecipitation assays showed Bcl-2 gene promoter regions are enriched with the active histone mark H4 lysine 16 acetylation, and this was increased in the autoantibody-treated fibroblasts. When H4 lysine 16 acetylation was decreased by knocking down its acetyltransferase, MOF (males absent on the first), the anti-HSP70 treatments failed to upregulate Bcl-2. This study describes a heretofore unknown, to our knowledge, pathogenic consequence of autoimmunity in which autoantibodies affect the epigenetic regulation of fibroblast apoptosis. In addition to IPF, this autoimmune process could also have relevance in other immunological syndromes characterized by anti-HSP70 autoimmunity. These findings lend credence to the importance of autoimmunity in IPF and illustrate pathways that could be targeted in innovative therapies for this morbid, medically refractory lung disease.

2.
Phys Rev Lett ; 133(3): 031001, 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39094161

RESUMEN

We show that next generation Cosmic Microwave Background (CMB) experiments will be capable of the first ever measurement of the inflaton coupling to other particles, opening a new window to probe the connection between cosmic inflation and particle physics. This sensitivity is based on the impact that the reheating phase after cosmic inflation has on the redshifting of cosmic perturbations. For our analysis we introduce a simple analytic method to estimate the sensitivity of future CMB observations to the reheating temperature and the inflaton coupling. Applying our method to LiteBIRD and CMB-S4 we find that, within a given model of inflation, these missions have the potential to impose both an upper and a lower bound on the inflaton coupling. Further improvement can be achieved if CMB data are combined with optical and 21 cm surveys. Our results demonstrate the potential of future observations to constrain microphysical parameters that can provide an important clue to understand how a given model of inflation may be embedded in a more fundamental theory of nature.

3.
Reprod Biol Endocrinol ; 22(1): 107, 2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39175038

RESUMEN

RESEARCH QUESTION: Does luteinizing hormone (LH) levels on human chorionic gonadotropin (HCG) trigger day (LHHCG) affect the clinical outcomes of patients with diminished ovarian reserve (DOR) undergoing gonadotropin-releasing hormone antagonist (GnRH-ant) protocol? METHODS: Retrospective analysis fresh embryo transfer cycles of DOR patients who underwent GnRH-ant protocol from August 2019 to June 2023. The participants were divided into different groups according to LHHCG level and age. The clinical data and outcomes were compared between groups. RESULTS: In patients with DOR, the HCG positive rate (59.3% versus 39.8%, P = 0.005), embryo implantation rate (34.5% versus 19.7%, P = 0.002), clinical pregnancy rate (49.2% versus 28.4%, P = 0.003), live birth rate (41.5% versus 22.7%, P = 0.005) in LHHCG < 2.58 IU/L group were significantly higher than LHHCG ≥ 2.58 IU/L group. There was no significant correlation between LHHCG level and clinical pregnancy in POSEIDON group 3. In POSEIDON group 4, the HCG positive rate (52.8% versus 27.0%, P = 0.015), embryo implantation rate (29.2% versus 13.3%, P = 0.023), clinical pregnancy rate (45.3% versus 18.9%, P = 0.010) in LHHCG < 3.14 IU/L group were significantly higher than LHHCG ≥ 3.14 IU/L group. Logistic regression analysis indicated that LHHCG level was an independent influencing factor for clinical pregnancy in POSEIDON group 4 patients (OR = 3.831, 95% CI: 1.379-10.643, P < 0.05). CONCLUSIONS: LHHCG level is an independent factor affecting pregnancy outcome of fresh embryo transfer in DOR patients undergoing GnRH-ant protocol, especially for advanced-aged women. LHHCG had a high predictive value for POSEIDON group 4 patients, and LHHCG ≥ 3.14 IU/L predicts poor pregnancy outcomes.


Asunto(s)
Gonadotropina Coriónica , Transferencia de Embrión , Hormona Liberadora de Gonadotropina , Hormona Luteinizante , Reserva Ovárica , Inducción de la Ovulación , Índice de Embarazo , Humanos , Femenino , Embarazo , Hormona Liberadora de Gonadotropina/antagonistas & inhibidores , Hormona Luteinizante/sangre , Gonadotropina Coriónica/administración & dosificación , Gonadotropina Coriónica/uso terapéutico , Adulto , Estudios Retrospectivos , Reserva Ovárica/efectos de los fármacos , Reserva Ovárica/fisiología , Inducción de la Ovulación/métodos , Transferencia de Embrión/métodos , Fertilización In Vitro/métodos , Antagonistas de Hormonas/uso terapéutico , Antagonistas de Hormonas/administración & dosificación , Resultado del Tratamiento , Infertilidad Femenina/terapia , Infertilidad Femenina/sangre , Infertilidad Femenina/tratamiento farmacológico , Resultado del Embarazo/epidemiología
4.
Brain Behav Immun ; 123: 108-122, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39260763

RESUMEN

Chronic HIV infection can dysregulate lipid/cholesterol metabolism in the peripheral system, contributing to the higher incidences of diabetes and atherosclerosis in HIV (+) individuals. Recently, accumulating evidence indicate that HIV proteins can also dysregulate lipid/cholesterol metabolism in the brain and such dysregulation could be linked with the pathogenesis of HIV-associated neurological disorders (HAND)/NeuroHIV. To further characterize the association between lipid/cholesterol metabolism and HAND, we employed HIV-inducible transactivator of transcription (iTAT) and control mice to compare their brain lipid profiles. Our results reveal that HIV-iTAT mice possess dysregulated lipid profiles and have increased numbers of lipid droplets (LDs) accumulation microglia (LDAM) in the brains. HIV protein TAT can upregulate LDs formation through enhancing the lipid/cholesterol synthesis in vitro. Mechanistically, HIV-TAT increases the expression of sterol regulatory element-binding protein 2 (SREBP2) through microRNA-124 downregulation. Cholesterol synthesis inhibition can block HIV-TAT-mediated NLRP3 inflammasome activation and microglial activation in vitro as well as mitigate aging-related behavioral impairment and memory deficiency in HIV-iTAT mice. Taken together, our results indicate an inherent role of lipid metabolism and LDAM in the pathogenesis of NeuroHIV (immunometabolism). These findings suggest that LDAM reversal through modulating lipid/cholesterol metabolism could be a novel therapeutic target for ameliorating NeuroHIV symptoms in chronic HIV (+) individuals.

5.
Artículo en Inglés | MEDLINE | ID: mdl-38568198

RESUMEN

Two Gram-negative, non-spore-forming, non-motile, non-flagellated bacteria, designated strains D6T and DH64T, were isolated from surface water of the Pacific Ocean. For strain D6T, growth occurred at 10-40 °C, pH 5.5-9.0 and in the presence of 0-8.0 % NaCl (w/v). For strain DH64T, growth occurred at 10-40 °C, pH 5.5-8.5 and in the presence of 0.5-8.0 % NaCl (w/v). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strains D6T and DH64T both belonged to the genera Flagellimonas, with the highest sequence identities to Flagellimonas taeanensis JCM 17757T (98.2 %) and Flagellimonas marinaquae JCM 11811T (98.6 %), respectively. The 16S rRNA gene sequence identity between strains D6T and DH64T was 95.9 %. The average amino acid identity and digital DNA-DNA hybridization values between the two strains and the nearest phylogenetic neighbours were 66.7-93.3 % and 16.1-38.5 %, respectively. The major respiratory quinone of both strains was menaquinone-6. The major polar lipid was phosphatidylethanolamine. The major fatty acids were identified similarly as iso-C15 : 1 G, iso-C15 : 0 and iso-C17 : 0 3-OH. The genomic G+C contents of strains D6T and DH64T were determined to be 45.5 and 42.6 mol%, respectively. The combined genotypic and phenotypic data show that the strains represent two novel species within genera Flagellimonas, for which the names Flagellimonas baculiformis sp. nov. and Flagellimonas crocea sp. nov. are proposed, with type strains D6T (=MCCC M28982T=KCTC 92604T) and DH64T (=MCCC M28986T=KCTC 92975T).


Asunto(s)
Ácidos Grasos , Cloruro de Sodio , Océano Pacífico , Composición de Base , Ácidos Grasos/química , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , ADN Bacteriano/genética , Técnicas de Tipificación Bacteriana , Agua de Mar
6.
Ther Drug Monit ; 46(5): 658-663, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-38648661

RESUMEN

BACKGROUND: This study comprehensively examined the demographic and clinical characteristics of patients undergoing valproic acid therapy and explored their potential impact on plasma valproic acid concentrations. All enrolled patients were administered the extended-release formulation. An in-depth investigation of factors, including dose, age, sex, body mass index, co-administered medications, and laboratory test findings, was conducted to evaluate their potential influence on study outcomes. METHODS: In total, 164 patients met the inclusion criteria and were included in the analysis. The patient age ranged from 13 to 60 years, with a median age of 25.71 years. Most patients (89%) received a daily dose of 1 g valproic acid. Co-administered psychiatric medications included aripiprazole, quetiapine, and lorazepam. Laboratory test results, such as hemoglobin and transaminase levels, were also collected as part of the study. RESULTS: The average plasma valproic acid plasma concentration was 79.8 mg/L. The dose significantly affected valproic acid concentrations, as a higher percentage of measurements exceeded the therapeutic range at a daily dose of 1 g. Furthermore, females exhibited significantly higher valproic acid concentrations compared with males at the same dose ( P < 0.05). However, different age groups showed no statistically significant differences in valproic acid concentrations ( P > 0.05). The co-administered antipsychotic and antidepressant medications significantly affected valproate concentrations, as reflected in the multiple regression model ( P < 0.01). CONCLUSIONS: This study offers valuable insights into the demographic and clinical characteristics of patients undergoing valproic acid therapy. It highlights the influence of dose, sex, and concomitant medications on plasma valproic acid concentrations. Overall, these findings can help guide dose adjustments and implement personalized treatment strategies in valproic acid therapy.


Asunto(s)
Antimaníacos , Trastorno Bipolar , Ácido Valproico , Humanos , Ácido Valproico/uso terapéutico , Ácido Valproico/sangre , Masculino , Adulto , Femenino , Trastorno Bipolar/tratamiento farmacológico , Trastorno Bipolar/sangre , Persona de Mediana Edad , Adulto Joven , Adolescente , Estudios Retrospectivos , Antimaníacos/uso terapéutico , Antimaníacos/sangre , Factores Sexuales , Pueblo Asiatico , Relación Dosis-Respuesta a Droga , Antipsicóticos/uso terapéutico , Antipsicóticos/sangre , Antipsicóticos/farmacocinética , China , Anticonvulsivantes/uso terapéutico , Anticonvulsivantes/sangre , Anticonvulsivantes/farmacocinética , Factores de Edad , Pueblos del Este de Asia
7.
Acta Radiol ; 65(9): 1039-1045, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39205433

RESUMEN

BACKGROUND: Preoperative prediction of lymphovascular space invasion (LVSI) is crucial for improving the prognosis of patients with cervical cancer. PURPOSE: To evaluate the value of preoperative amide proton transfer (APT) imaging combined with serum CA125 levels for predicting LVSI in cervical cancer. MATERIAL AND METHODS: This retrospective study included 80 patients with cervical cancer who underwent preoperative magnetic resonance imaging, including APT imaging. Serum CA125 levels were measured using a fully automated immunoassay analyzer and chemiluminescence method. The presence of LVSI was determined based on the pathological results after surgery. RESULTS: Among the 40 patients who met the requirements, 29 had postoperative pathological confirmation of LVSI, while 11 did not. The areas under the receiver operating characteristic curves (AUC) of preoperative APT and CA125 levels predicting LVSI were 0.889 and 0.687, respectively. When the APT value was 2.9%, the corresponding Youden index was the highest (0.702), with a sensitivity of 79.3% and specificity of 90.9%. When the critical value of the preoperative serum CA15 level was 25.3 u/mL, the corresponding Youden index was the highest (0.508), with a sensitivity of 69.0% and a specificity of 81.8%. The sensitivity and specificity of preoperative APT imaging combined with serum CA125 in predicting LVSI were 82.7% and 100%, respectively, with a Youden's index of 0.828 and an AUC of 0.923. CONCLUSION: The combination of preoperative APT imaging and serum CA125 levels is valuable for predicting LVSI in cervical cancer. Diagnostic efficacy is highest when the APT value is >2.9% and the serum CA125 level is >25.3 u/mL.


Asunto(s)
Antígeno Ca-125 , Imagen por Resonancia Magnética , Invasividad Neoplásica , Neoplasias del Cuello Uterino , Humanos , Femenino , Neoplasias del Cuello Uterino/sangre , Neoplasias del Cuello Uterino/diagnóstico por imagen , Neoplasias del Cuello Uterino/cirugía , Neoplasias del Cuello Uterino/patología , Persona de Mediana Edad , Estudios Retrospectivos , Antígeno Ca-125/sangre , Adulto , Imagen por Resonancia Magnética/métodos , Anciano , Sensibilidad y Especificidad , Metástasis Linfática/diagnóstico por imagen , Valor Predictivo de las Pruebas , Amidas , Protones , Cuidados Preoperatorios/métodos , Biomarcadores de Tumor/sangre
8.
PLoS Genet ; 17(4): e1009505, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33886546

RESUMEN

The development of male and female gametophytes is a pre-requisite for successful reproduction of angiosperms. Factors mediating vesicular trafficking are among the key regulators controlling gametophytic development. Fusion between vesicles and target membranes requires the assembly of a fusogenic soluble N-ethylmaleimide sensitive factor attachment protein receptors (SNAREs) complex, whose disassembly in turn ensures the recycle of individual SNARE components. The disassembly of post-fusion SNARE complexes is controlled by the AAA+ ATPase N-ethylmaleimide-sensitive factor (Sec18/NSF) and soluble NSF attachment protein (Sec17/α-SNAP) in yeast and metazoans. Although non-canonical α-SNAPs have been functionally characterized in soybeans, the biological function of canonical α-SNAPs has yet to be demonstrated in plants. We report here that the canonical α-SNAP in Arabidopsis is essential for male and female gametophytic development. Functional loss of the canonical α-SNAP in Arabidopsis results in gametophytic lethality by arresting the first mitosis during gametogenesis. We further show that Arabidopsis α-SNAP encodes two isoforms due to alternative splicing. Both isoforms interact with the Arabidopsis homolog of NSF whereas have distinct subcellular localizations. The presence of similar alternative splicing of human α-SNAP indicates that functional distinction of two α-SNAP isoforms is evolutionarily conserved.


Asunto(s)
Arabidopsis/genética , Gametogénesis/genética , Desarrollo de la Planta/genética , Proteínas Solubles de Unión al Factor Sensible a la N-Etilmaleimida/genética , ATPasas Asociadas con Actividades Celulares Diversas/genética , Empalme Alternativo/genética , Arabidopsis/crecimiento & desarrollo , Células Germinativas de las Plantas/crecimiento & desarrollo , Mitosis/genética , Proteínas Sensibles a N-Etilmaleimida/genética , Isoformas de Proteínas/genética
9.
Small ; : e2307252, 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-38054813

RESUMEN

Efficient bifunctional hydrogen electrocatalysis, encompassing both hydrogen evolution reaction (HER) and hydrogen oxidation reaction (HOR), is of paramount significance in advancing hydrogen-based societies. While non-precious-metal-based catalysts, particularly those based on nickel (Ni), are essential for alkaline HER/HOR, their intrinsic catalytic activity often falls short of expectations. Herein, an internal electric field (IEF) strategy is introduced for the engineering of heterogeneous nickel-vanadium oxide nanosheet arrays grown on porous nickel foam (Ni-V2 O3 /PNF) as bifunctional electrocatalysts for hydrogen electrocatalysis. Strikingly, the Ni-V2 O3 /PNF delivers 10 mA cm-2 at an overpotential of 54 mV for HER and a mass-specific kinetic current of 19.3 A g-1 at an overpotential of 50 mV for HOR, placing it on par with the benchmark 20% Pt/C, while exhibiting enhanced stability in alkaline electrolytes. Density functional theory calculations, in conjunction with experimental characterizations, unveil that the interface IEF effect fosters asymmetrical charge distributions, which results in more thermoneutral hydrogen adsorption Gibbs free energy on the electron-deficient Ni side, thus elevating the overall efficiency of both HER and HOR. The discoveries reported herein guidance are provided for further understanding and designing efficient non-precious-metal-based electrocatalysts through the IEF strategy.

10.
EMBO Rep ; 22(8): e51978, 2021 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-34232545

RESUMEN

Zika virus (ZIKV) infection during pregnancy is linked to various developmental brain disorders. Infants who are asymptomatic at birth might have postnatal neurocognitive complications. However, animal models recapitulating these neurocognitive phenotypes are lacking, and the circuit mechanism underlying behavioral abnormalities is unknown. Here, we show that ZIKV infection during mouse pregnancy induces maternal immune activation (MIA) and leads to autistic-like behaviors including repetitive self-grooming and impaired social memory in offspring. In the medial prefrontal cortex (mPFC), ZIKV-affected offspring mice exhibit excitation and inhibition imbalance and increased cortical activity. This could be explained by dysregulation of inhibitory neurons and synapses, and elevated neural activity input from mPFC-projecting ventral hippocampus (vHIP) neurons. We find structure alterations in the synaptic connections and pattern of vHIP innervation of mPFC neurons, leading to hyperconnectivity of the vHIP-mPFC pathway. Decreasing the activity of mPFC-projecting vHIP neurons with a chemogenetic strategy rescues social memory deficits in ZIKV offspring mice. Our studies reveal a hyperconnectivity of vHIP to mPFC projection driving social memory deficits in mice exposed to maternal inflammation by ZIKV.


Asunto(s)
Infección por el Virus Zika , Virus Zika , Animales , Femenino , Hipocampo , Inflamación , Ratones , Corteza Prefrontal , Embarazo
11.
Artículo en Inglés | MEDLINE | ID: mdl-37000637

RESUMEN

A Gram-stain-negative, non-motile, rod-shaped bacterial strain, designated C281T, was isolated from seawater sampled at the Marshallese seamount chain. Results of 16S rRNA gene analysis revealed that strain C281T was most closely related to Membranihabitans marinus CZ-AZ5T with 92.7 % sequence similarity. Phylogenetic analysis indicated that the new isolate represented a novel species by forming a distinctive lineage within the family Saprospiraceae. The DNA G+C content of strain C281T was 38.4 mol%. The genome sizes of strain C281T and the reference strain M. marinus CZ-AZ5T were 5 962 917 and 5 395 999 bp, respectively. The average nucleotide identity and in silico DNA-DNA hybridization values between strains C281T and M. marinus CZ-AZ5T were found to be low (69.3 and 17.6 %, respectively). Different functional genes were found in the genome of strain C281T, such as CZC CBA, polysaccharide utilization loci and linear azol(in)e-containing peptide cluster coding genes. The NaCl range for growth was 0.5-15.0 %. Positive results were obtained for hydrolysis of Tween 60 and urease. MK-7 was the sole respiratory quinone. The major fatty acids were C16 : 1 ω6c and/or C16 : 1 ω7c, iso-C15 : 0 and iso-C15 : 1 F. The major polar lipids of strain C281T were phosphatidylethanolamine, phosphatidylglycerol, two unidentified lipids and five unidentified glycolipids. On the basis of its taxonomic characteristics, the isolate represents a novel species of the genus Membranihabitans, for which the name Membranihabitans maritimus sp. nov. (type strain C281T=KCTC 92171T=MCCC M27001T) is proposed.


Asunto(s)
Ácidos Grasos , Fosfolípidos , Ácidos Grasos/química , Fosfolípidos/química , Filogenia , ARN Ribosómico 16S/genética , ADN Bacteriano/genética , Composición de Base , Análisis de Secuencia de ADN , Técnicas de Tipificación Bacteriana , Agua de Mar/microbiología
12.
Biol Cell ; 114(10): 276-292, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35713972

RESUMEN

BACKGROUND: HIV-1 Nef regulates several cellular functions in an infected cell which results in viral persistence and AIDS pathogenesis. The currently understood molecular mechanism(s) underlying Nef-dependent cellular function(s) are unable to explain how events are coordinately regulated in the host cell. Intracellular membranous trafficking maintains cellular homeostasis and is regulated by Rab GTPases - a member of the Ras superfamily. RESULTS: In the current study, we tried to decipher the role of Nef on the Rab GTPases-dependent complex and vesicular trafficking. Expression profiling of Rabs in Nef-expressing cells showed that Nef differentially regulates the expression of individual Rabs in a cell-specific manner. Further analysis of Rabs in HIV-1NL4-3 or ΔNef infected cells demonstrated that the Nef protein is responsible for variation in Rabs expression. Using a panel of competitive peptide inhibitors against Nef, we identified the critical domain of HIV-1 Nef involved in modulation of Rabs expression. The molecular function of Nef-mediated upregulation of Rab5 and Rab7 and downregulation of Rab11 increased the transport of SERINC5 from the cell surface to the lysosomal compartment. Moreover, the Nef-dependent increase in Rab27 expression assists exosome release. Reversal of Rabs expression using competitive inhibitors against Nef and manipulation of Rabs expression reduced viral release and infectivity of progeny virions. CONCLUSION: This study demonstrates that Nef differentially regulates the expression of Rab proteins in HIV-1 infected cells to hijack the host intracellular trafficking, which augments viral replication and HIV-1 pathogenesis. SIGNIFICANCE: Our study emphasized the indispensable role of HIV-1 protein Nef on various aspects of the intracellular trafficking regulated by Rabs GTPases, which explained how HIV-1 Nef may hijack membrane trafficking pathways in infected cells.


Asunto(s)
VIH-1 , VIH-1/fisiología , Proteínas de la Membrana/metabolismo , Virión/química , Virión/metabolismo , Productos del Gen nef del Virus de la Inmunodeficiencia Humana/análisis , Productos del Gen nef del Virus de la Inmunodeficiencia Humana/metabolismo , Proteínas de Unión al GTP rab/metabolismo
13.
Phys Chem Chem Phys ; 25(8): 6362-6368, 2023 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-36779323

RESUMEN

Batteries have become a ubiquitous daily necessity, which are popularly applied to mobile phones and electric vehicles according to their size. Improving the battery cycle life and storage is important, but unexpected discharge products still restrict the upper limit of batter performance such as Li2O2, LiO2, and Li2S. In this study, we calculated electrons and phonons presenting the basic energy states in crystal using the first-principles calculations. The Li2O2 and Li2S are almost insulating due to the wide bandgap from their electronic structure, and doped-active p-orbital may be one of the pathways to improve crystal conduction due to the tendency of the density of states. The LiO2 is metallic, and the electronic structure and phonons show that the discharge products have an ionic feature. In addition, the ionic crystal can produce a larger DC permittivity because it possesses macroscopic polarisation. For Li2O2 and Li2S, the Raman peak of the O-O bonding is strong, while the Raman peak of the S-ion is very weak. The enhanced Raman peak of the S-ion presents a possibility to prevent the shuttle effect in Li-S batteries.

14.
Angew Chem Int Ed Engl ; 62(21): e202301126, 2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-36961328

RESUMEN

N-heterocyclic carbene (NHC)-catalyzed enantioselective Mannich-type reactions of the biomass-derived platform compound 5-(chloromethyl)furfural (CMF) with imines were developed. A series of high-value-added chiral amines were afforded in good to high yields with excellent regio- and enantioselectivities. The bifunctional NHC derived from ʟ-pyroglutamic acid efficiently steered the remote addition of the trienolate intermediate to the imine in a highly stereocontrolled manner. This represents the first enantioselective reaction proceeding via an NHC-bound trienolate intermediate.

15.
Plant J ; 106(3): 801-816, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33595139

RESUMEN

Elucidating the biochemical and molecular basis of premature abscission in fruit crops should help develop strategies to enhance fruit set and yield. Here, we report that LcERF2 contributes to differential abscission rates and responses to ethylene in Litchi chinensis (litchi). Reduced LcERF2 expression in litchi was observed to reduce fruit abscission, concurrent with enhanced pedicel growth and increased levels of hexoses, particularly galactose, as well as pectin abundance in the cell wall. Ecoptic expression of LcERF2 in Arabidopsis thaliana caused enhanced petal abscission, together with retarded plant growth and reduced pedicel galactose and pectin contents. Transcriptome analysis indicated that LcERF2 modulates the expression of genes involved in cell wall modification. Yeast one-hybrid, dual-luciferase reporter and electrophoretic mobility shift assays all demonstrated that a UDP-glucose-4-epimerase gene (LcUGE) was the direct downstream target of LcERF2. This result was further supported by a significant reduction in the expression of the A. thaliana homolog AtUGE2-4 in response to LcERF2 overexpression. Significantly reduced pedicel diameter and enhanced litchi fruit abscission were observed in response to LcUGE silencing. We conclude that LcERF2 mediates fruit abscission by orchestrating cell wall metabolism, and thus pedicel growth, in part by repressing the expression of LcUGE.


Asunto(s)
Pared Celular/metabolismo , Frutas/metabolismo , Litchi/metabolismo , Proteínas de Plantas/metabolismo , UDPglucosa 4-Epimerasa/metabolismo , Arabidopsis , Ensayo de Cambio de Movilidad Electroforética , Frutas/enzimología , Frutas/crecimiento & desarrollo , Perfilación de la Expresión Génica , Genes de Plantas/genética , Litchi/enzimología , Litchi/crecimiento & desarrollo , Proteínas de Plantas/genética , Plantas Modificadas Genéticamente , UDPglucosa 4-Epimerasa/genética
16.
BMC Pregnancy Childbirth ; 22(1): 906, 2022 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-36471261

RESUMEN

BACKGROUND: Embryonic chromosomal abnormality is one of the significant causative factors of pregnancy loss. Our goal was to investigate the differences of chromosomal abnormality between different conception modes in miscarried products of conception (POCs). METHODS: A retrospective study included 262 miscarried POCs from 167 women undergoing assisted reproductive treatment (ART) and 95 spontaneous pregnant (SP) women during March 2019 to March 2022 in Renmin Hospital of Wuhan University. Subgroups were divided according to age, fertilization method, types and stages of embryo transfer. The profiles of cytogenetic abnormalities in the miscarried POCs were measured via next-generation sequencing. RESULTS: The rate of chromosomal abnormality in the fresh embryo transfer group and the cleavage embryo transfer group was significantly higher than that in the frozen embryo transfer group (79.2% vs. 36%, P = 0.0001) and the blastocyst transfer group (66.7% vs. 32.1%, P = 0.0001) respectively. There was no significant difference in the rate of chromosomal abnormalities when compared by maternal age (49.2% vs. 62%, P = 0.066), types of conception (49.7% vs. 57.9%, P = 0.202), fertilization method (49.6% vs. 48.7%, P = 0.927) and frequency of abortion (56% vs. 47.6%, P = 0.183). However, the women aged ≥ 35 years had more frequent numerical abnormality (P = 0.002); patients using assisted reproductive technology had more rate of chromosomal structural abnormalities (26.5% vs. 7.3%, P = 0.005); the ICSI fertilization group has more frequency of deletion/microdeletion than the IVF fertilization group (80% vs. 31.3%, P = 0.019). CONCLUSION: Blastocyst transfer might help to reduce the incidence of miscarriage. In addition, "freezing all" should be considered if encountered hyper ovarian stimulation, to avoid the negative effect of high estrogen environment on embryo development. The higher incidence of structural abnormalities in miscarried POCs from assisted reproductive patients reminds us to pay attention to the safety of the technology for offspring.


Asunto(s)
Aborto Espontáneo , Trastornos de los Cromosomas , Embarazo , Humanos , Femenino , Fertilización In Vitro , Estudios Retrospectivos , Transferencia de Embrión/métodos , Aborto Espontáneo/epidemiología , Aborto Espontáneo/genética , Aberraciones Cromosómicas
17.
Phys Rev Lett ; 126(1): 011601, 2021 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-33480754

RESUMEN

We derive the generalized partial wave expansion for N→M scattering amplitude in terms of spinor helicity variables. The basis amplitudes of the expansion with definite angular momentum j consist of the Poincaré Clebsch-Gordan coefficients. Moreover, we obtain a series of selection rules that restrict the anomalous dimension matrix of effective operators and how effective operators contribute to some 2→N amplitudes at the loop level.

18.
Appl Opt ; 60(7): 2100-2108, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33690304

RESUMEN

Intelligent photonic circuits (IPCs) tuned with an appropriate phase-shift vector could enable a photonic intelligent matrix possibly implemented in multiple neural layers for a task-oriented topologies. A photonic Mach-Zehnder Interferometer (MZI) is a fundamental photonic component in IPCs, whose matrix representation could be broadcasted into an arbitrary matrix that is equipped with an optimized phase-shift vector. The initialized MZIs' phases are tentatively probed between analytical elements and a digital weight matrix that is learned from samples with efficient compatible learning for complex-valued neural networks. Nonlinear least squares is utilized to formulate a phase determination system to refine the optimal phase-shift solutions. The robustness of phase determination system for photonic neural networks is discussed in detail. For a preliminary implementation, a basic 4×4 intelligent photonic neural network is utilized to verify the proof of concept on phase-shift determination in IPC through numerical experiments.

19.
Int J Mol Sci ; 22(1)2021 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-33466443

RESUMEN

Fruit cracking is a disorder of fruit development in response to internal or external cues, which causes a loss in the economic value of fruit. Therefore, exploring the mechanism underlying fruit cracking is of great significance to increase the economic yield of fruit trees. However, the molecular mechanism underlying fruit cracking is still poorly understood. Litchi, as an important tropical and subtropical fruit crop, contributes significantly to the gross agricultural product in Southeast Asia. One important agricultural concern in the litchi industry is that some famous varieties with high economic value such as 'Nuomici' are susceptible to fruit cracking. Here, the cracking-susceptible cultivar 'Nuomici' and cracking-resistant cultivar 'Huaizhi' were selected, and the samples including pericarp and aril during fruit development and cracking were collected for RNA-Seq analysis. Based on weighted gene co-expression network analysis (WGCNA) and the "ball-skin versus bladder effect" theory (fruit cracking occurs upon the aril expanding pressure exceeds the pericarp strength), it was found that seven co-expression modules genes (1733 candidate genes) were closely associated with fruit cracking in 'Nuomici'. Importantly, we propose that the low expression level of genes related to plant hormones (Auxin, Gibberellins, Ethylene), transcription factors, calcium transport and signaling, and lipid synthesis might decrease the mechanical strength of pericarp in 'Nuomici', while high expression level of genes associated with plant hormones (Auxin and abscisic acid), transcription factors, starch/sucrose metabolism, and sugar/water transport might increase the aril expanding pressure, thereby resulting in fruit cracking in 'Nuomici'. In conclusion, our results provide comprehensive molecular events involved in the "ball-skin versus bladder effect" on fruit cracking in litchi.


Asunto(s)
Frutas/genética , Litchi/genética , Enfermedades de las Plantas/genética , Metabolismo de los Hidratos de Carbono/genética , Regulación de la Expresión Génica de las Plantas/genética , Reguladores del Crecimiento de las Plantas/genética , Proteínas de Plantas/genética , RNA-Seq/métodos , Transducción de Señal/genética , Factores de Transcripción/genética
20.
BMC Pregnancy Childbirth ; 20(1): 394, 2020 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-32641013

RESUMEN

BACKGROUND: Compared with Severe Acute Respiratory Syndrome (SARS) and Middle East Respiratory Syndrome (MERS), Corona Virus Disease 2019(COVID-19) spread more rapidly and widely. The population was generally susceptible. However, reports on pregnant women infected with SARS-CoV-2 were very limited. By sharing the clinical characteristics, treatments and outcomes of 18 patients with COVID-19 during late pregnancy, we hope to provide some references for obstetric treatment and management. METHODS: A total of 18 patients with COVID-19 treated at Renmin Hospital of Wuhan University were collected. The epidemiological characteristics, clinical manifestations, laboratory tests, chest CT and pregnancy outcomes were performed for analysis. RESULTS: 1. 18 cases of late pregnancy infected with SARS-CoV-2 pneumonia were delivered at 35 + 5 weeks to 41 weeks. According to the clinical classification of COVID-19, 1 case was mild type, 16 cases were ordinary type, and 1 case was severe type. 2. According to imaging examinations: 15 (83%) cases showed unilateral or bilateral pneumonia, 2 (11%) cases had pulmonary infection with pleural effusion, and 1 (6%) case had no abnormal imaging changes. 8 (44%) cases were positive and 10 (56%) cases were negative for nasopharyngeal-swab tests of SARS-CoV-2. 3. Among the 18 newborns, there were 3 (17%) premature infants, 1 (6%) case of mild asphyxia, 5 (28%) cases of bacterial pneumonia, 1 (6%) case of gastrointestinal bleeding, 1 (6%) case of necrotizing enteritis, 2 (11%) cases of hyperbilirubinemia and 1 (6%) case of diarrhea. All the newborns were negative for the first throat swab test of SARS-CoV-2 after birth. 4. Follow-up to Mar 7, 2020, no maternal and neonatal deaths occurred. CONCLUSIONS: The majority of patients in late term pregnancy with COVID-19 were of ordinary type, and they were less likely to develop into critical pneumonia after early isolation and antiviral treatment. Vertical transmission of SARS-CoV-2 was not detected, but the proportion of neonatal bacterial pneumonia was higher than other neonatal diseases in newborns.


Asunto(s)
Betacoronavirus , Infecciones por Coronavirus/complicaciones , Transmisión Vertical de Enfermedad Infecciosa/estadística & datos numéricos , Neumonía Viral/complicaciones , Complicaciones Infecciosas del Embarazo/virología , Adulto , COVID-19 , China/epidemiología , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/virología , Femenino , Humanos , Recién Nacido , Pandemias , Neumonía Viral/epidemiología , Neumonía Viral/virología , Embarazo , Complicaciones Infecciosas del Embarazo/epidemiología , Resultado del Embarazo , Nacimiento Prematuro/epidemiología , Nacimiento Prematuro/virología , SARS-CoV-2
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