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1.
Int J Cardiol ; 413: 132345, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38996817

RESUMEN

BACKGROUND: Door-to-balloon time (DTBT) for ST-elevation myocardial infarction (STEMI) is a performance metric by which primary percutaneous coronary intervention (PPCI) services are assessed. METHODS: Consecutive patients presenting with STEMI undergoing PPCI between January 2007 to December 2019 from the Singapore Myocardial Infarction Registry were included. Patients were stratified based on DTBT (≤60 min, 61-90 min, 91-180 min) and Killip status (I-III vs. IV). Outcomes assessed included all-cause mortality and major adverse cardiovascular events (MACE) at 30-days and 1-year. RESULTS: In total, 13,823 patients were included, with 82.59% achieving DTBT ≤90 min and 49.77% achieving DTBT ≤60 min. For Killip I-III (n = 11,591,83.85%), the median DTBT was 60[46-78]min. The 30-day all-cause mortality for DTBT of ≤60 min, 61-90 min and 91-180 min was 1.08%, 2.17% and 4.33% respectively (p < 0.001). On multivariate analysis, however, there was no significant difference for 30-day and 1-year outcomes across all DTBT (p > 0.05). For Killip IV, the median DTBT was 68[51-91]min. The 30-day all-cause mortality for DTBT of ≤60 min, 61-90 min and 91-180 min was 11.74%, 20.48% and 35.06% respectively (p < 0.001). On multivariate analysis for 30-day and 1-year outcomes, DTBT 91-180 min was an independent predictor of worse outcomes (p < 0.05), but there was no significant difference between DTBT of ≤60 min and 61-90 min (p > 0.05). CONCLUSION: In Killip I-III patients, DTBT had no significant impact on outcomes upon adjustment for confounders. Conversely, for Killip IV patients, a DTBT of >90 min was associated with significantly higher adverse outcomes, with no differences between a DTBT of ≤60 min vs. 61-90 min. Outcomes in STEMI involve a complex interplay of factors and recommendations of a lowered DTBT of ≤60 min will require further evaluation.

2.
Nat Commun ; 15(1): 5915, 2024 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-39003277

RESUMEN

GeTe is a promising p-type material with increasingly enhanced thermoelectric properties reported in recent years, demonstrating its superiority for mid-temperature applications. In this work, the thermoelectric performance of GeTe is improved by a facile composite approach. We find that incorporating a small amount of boron particles into the Bi-doped GeTe leads to significant enhancement in power factor and simultaneous reduction in thermal conductivity, through which the synergistic modulation of electrical and thermal transport properties is realized. The thermal mismatch between the boron particles and the matrix induces high-density dislocations that effectively scatter the mid-frequency phonons, accounting for a minimum lattice thermal conductivity of 0.43 Wm-1K-1 at 613 K. Furthermore, the presence of boron/GeTe interfaces modifies the interfacial potential barriers, resulting in increased Seebeck coefficient and hence enhanced power factor (25.4 µWcm-1K-2 at 300 K). Consequently, we obtain a maximum figure of merit Zmax of 4.0 × 10-3 K-1 at 613 K in the GeTe-based composites, which is the record-high value in GeTe-based thermoelectric materials and also superior to most of thermoelectric systems for mid-temperature applications. This work provides an effective way to further enhance the performance of GeTe-based thermoelectrics.

3.
J Am Chem Soc ; 146(25): 17355-17364, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38870542

RESUMEN

GeSe, an analogue of SnSe, shows promise in exhibiting exceptional thermoelectric performance in the Pnma phase. The constraints on its dopability, however, pose challenges in attaining optimal carrier concentrations and improving ZT values. This study demonstrates a crystal structure evolution strategy for achieving highly doped samples and promising ZTs in GeSe via LiBiTe2 alloying. A rhombohedral phase (R3m) can be stabilized in the GeSe-LiBiTe2 system, further evolving into a cubic (Fm3̅m) phase with a rising temperature. The band structures of GeSe-LiBiTe2 in the rhombohedral and cubic phases feature a similar multiple-valley energy-converged valence band of L and Σ bands. The observed high carrier concentration (∼1020 cm-3) reflects the effective convergence of these bands, enabling a high density-of-states effective mass and an enhanced power factor. Moreover, a very low lattice thermal conductivity of 0.6-0.5 W m-1 K-1 from 300 to 723 K is achieved in 0.9GeSe-0.1LiBiTe2, approaching the amorphous limit value. This remarkably low lattice thermal conductivity is related to phonon scattering from point defects, planar vacancies, and ferroelectric instability-induced low-energy Einstein oscillators. Finally, a maximum ZT value of 1.1 to 1.3 at 723 K is obtained, with a high average ZT value of over 0.8 (400-723 K) in 0.9GeSe-0.1LiBiTe2 samples. This study establishes a viable route for tailoring crystal structures to significantly improve the performance of GeSe-related compounds.

4.
Exp Eye Res ; 244: 109948, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38815790

RESUMEN

Severe corneal injury can lead to blindness even after prompt treatment. 14-3-3zeta, a member of an adaptor protein family, contributes to tissue repair by enhancing cellular viability and inhibiting fibrosis and inflammation in renal disease or arthritis. However, its role in corneal regeneration is less studied. In this study, filter disc of 2-mm diameter soaked in sodium hydroxide with a concentration of 0.5 N was placed at the center of the cornea for 30 s to establish a mouse model of corneal alkali injury. We found that 14-3-3zeta, which is mainly expressed in the epithelial layer, was upregulated following injury. Overexpression of 14-3-3zeta in ocular tissues via adeno-associated virus-mediated subconjunctival delivery promoted corneal wound healing, showing improved corneal structure and transparency. In vitro studies on human corneal epithelial cells showed that 14-3-3zeta was critical for cell proliferation and migration. mRNA-sequencing in conjunction with KEGG analysis and validation experiments revealed that 14-3-3zeta regulated the mRNA levels of ITGB1, PIK3R1, FGF5, PRKAA1 and the phosphorylation level of Akt, suggesting the involvement of the PI3K-Akt pathway in 14-3-3zeta-mediated tissue repair. 14-3-3zeta is a potential novel therapeutic candidate for treating severe corneal injury.


Asunto(s)
Proteínas 14-3-3 , Quemaduras Químicas , Lesiones de la Cornea , Cicatrización de Heridas , Animales , Humanos , Masculino , Ratones , Proteínas 14-3-3/metabolismo , Proteínas 14-3-3/genética , Proteínas 14-3-3/biosíntesis , Western Blotting , Quemaduras Químicas/metabolismo , Quemaduras Químicas/patología , Quemaduras Químicas/tratamiento farmacológico , Movimiento Celular , Proliferación Celular , Células Cultivadas , Lesiones de la Cornea/metabolismo , Lesiones de la Cornea/patología , Lesiones de la Cornea/genética , Modelos Animales de Enfermedad , Epitelio Corneal/metabolismo , Epitelio Corneal/efectos de los fármacos , Epitelio Corneal/lesiones , Quemaduras Oculares/inducido químicamente , Regulación de la Expresión Génica , Homeostasis , Ratones Endogámicos C57BL , Hidróxido de Sodio , Cicatrización de Heridas/efectos de los fármacos , Cicatrización de Heridas/fisiología
5.
Adv Mater ; 36(30): e2403651, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38692649

RESUMEN

Photocatalytic CO2 reduction to high-value-added C2+ products presents significant challenges, which is attributed to the slow kinetics of multi-e- CO2 photoreduction and the high thermodynamic barrier for C-C coupling. Incorporating redox-active Co2+/Ni2+ cations into lead halide photocatalysts has high potentials to improve carrier transport and introduce charge polarized bimetallic sites, addressing the kinetic and thermodynamic issues, respectively. In this study, a coordination-driven synthetic strategy is developed to introduce 3d transition metals into the interlamellar region of layered organolead iodides with atomic precision. The resultant bimetallic halide hybrids exhibit selective photoreduction of CO2 to C2H5OH using H2O vapor at the evolution rates of 24.9-31.4 µmol g-1 h-1 and high selectivity of 89.5-93.6%, while pristine layered lead iodide yields only C1 products. Band structure calculations and photoluminescence studies indicate that the interlayer Co2+/Ni2+ species greatly contribute to the frontier orbitals and enhance exciton dissociation into free carriers, facilitating carrier transport between adjacent lead iodide layers. In addition, Bader charge distribution calculations and in situ experimental spectroscopic studies reveal that the asymmetric Ni-O-Pb bimetallic catalytic sites exhibit intrinsic charge polarization, promoting C-C coupling and leading to the formation of the key *OC-CHO intermediate.

6.
J Ovarian Res ; 17(1): 116, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38807145

RESUMEN

BACKGROUND: PCOS patients with unexpectedly low oocyte yield following conventional ovarian stimulation are referred to as suboptimal responders. However, identifying suboptimal responders presents a significant challenge within reproductive medicine and limited research exists on the occurrence of suboptimal response. This analysis aimed to develop a predictive model of suboptimal response during in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) treatments in PCOS patients. METHODS: This retrospective study involved a cohort of 313 PCOS patients undergoing their first IVF/ICSI cycle from 2019 to 2022. Univariate logistic regression analyses, least absolute shrinkage, selection operator regression analysis, and recursive feature elimination were employed to identify relevant characteristics and construct predictive models. Moreover, a nomogram was constructed based on the best model. Receiver operating characteristic curves, decision curve analysis (DCA), and calibration curves were used to evaluate the model. RESULTS: The predictors included in the model were age, Anti-Mullerian hormone, antral follicle count, and basal follicle-stimulating hormone. The area under the receiver operating characteristic curve (AUC) was 0.7702 (95% confidence interval 0.7157-0.8191). The AUC, along with the DCA curve and calibration curve, demonstrated a satisfactory level of congruence and discrimination ability. CONCLUSION: The nomogram effectively predicted the probability of suboptimal response in PCOS patients undergoing gonadotropin-releasing hormone antagonist protocol during IVF/ICSI treatment.


Asunto(s)
Fertilización In Vitro , Hormona Liberadora de Gonadotropina , Inducción de la Ovulación , Síndrome del Ovario Poliquístico , Inyecciones de Esperma Intracitoplasmáticas , Humanos , Femenino , Síndrome del Ovario Poliquístico/tratamiento farmacológico , Hormona Liberadora de Gonadotropina/antagonistas & inhibidores , Adulto , Inyecciones de Esperma Intracitoplasmáticas/métodos , Fertilización In Vitro/métodos , Inducción de la Ovulación/métodos , Estudios Retrospectivos , Nomogramas , Embarazo , Curva ROC
7.
BMC Oral Health ; 24(1): 629, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38807098

RESUMEN

BACKGROUND: In orthodontics, anterior open bite is a common malocclusion that recurs frequently. Because the causes of anterior open bite are so varied, medical professionals must create customized treatment programs for each patient based on their unique etiology. Through the lowering of the posterior teeth, closure of the anterior teeth gap, and cooperation with intermaxillary traction, the treatment plan outlined in this case study sought to achieve a stable occlusion. CASE PRESENTATION: This case report aims to describe an orthodontic camouflage treatment of a 15-year-old female patient with anterior open bite, arch width discrepancy and a history of temporomandibular joint disorder. The patient was treated with intermaxillary vertical elastics and the multiple edgewise arch wire (MEAW) approach. A satisfactory occlusion with a neutral molar relationship was attained after 29 months of orthodontic therapy. The condylography recording showed that this patient's occlusion tended to be more stable both before and after our treatment. The purpose of this case study is to provide an overview of an orthodontic camouflage treatment for a female patient, who had a history of temporomandibular joint disease, anterior open bite, and arch width disparity. CONCLUSIONS: Our results demonstrated that more attention should be paid to levelling the occlusal plane, intrusion of the molars, decompression of temporomandibular joints and the etiology factors of malocclusion during the orthodontic period for those patients with anterior open bite.


Asunto(s)
Mordida Abierta , Trastornos de la Articulación Temporomandibular , Humanos , Femenino , Adolescente , Mordida Abierta/terapia , Trastornos de la Articulación Temporomandibular/terapia , Ortodoncia Correctiva/métodos , Cefalometría , Planificación de Atención al Paciente
8.
Blood Adv ; 8(12): 3200-3213, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38621200

RESUMEN

ABSTRACT: A comprehensive international consensus on the cytogenetic risk-group stratification of KMT2A-rearranged (KMT2A-r) pediatric acute myeloid leukemia (AML) is lacking. This retrospective (2005-2016) International Berlin-Frankfurt-Münster Study Group study on 1256 children with KMT2A-r AML aims to validate the prognostic value of established recurring KMT2A fusions and additional cytogenetic aberrations (ACAs) and to define additional, recurring KMT2A fusions and ACAs, evaluating their prognostic relevance. Compared with our previous study, 3 additional, recurring KMT2A-r groups were defined: Xq24/KMT2A::SEPT6, 1p32/KMT2A::EPS15, and 17q12/t(11;17)(q23;q12). Across 13 KMT2A-r groups, 5-year event-free survival probabilities varied significantly (21.8%-76.2%; P < .01). ACAs occurred in 46.8% of 1200 patients with complete karyotypes, correlating with inferior overall survival (56.8% vs 67.9%; P < .01). Multivariable analyses confirmed independent associations of 4q21/KMT2A::AFF1, 6q27/KMT2A::AFDN, 10p12/KMT2A::MLLT10, 10p11.2/KMT2A::ABI1, and 19p13.3/KMT2A::MLLT1 with adverse outcomes, but not those of 1q21/KMT2A::MLLT11 and trisomy 19 with favorable and adverse outcomes, respectively. Newly identified ACAs with independent adverse prognoses were monosomy 10, trisomies 1, 6, 16, and X, add(12p), and del(9q). Among patients with 9p22/KMT2A::MLLT3, the independent association of French-American-British-type M5 with favorable outcomes was confirmed, and those of trisomy 6 and measurable residual disease at end of induction with adverse outcomes were identified. We provide evidence to incorporate 5 adverse-risk KMT2A fusions into the cytogenetic risk-group stratification of KMT2A-r pediatric AML, to revise the favorable-risk classification of 1q21/KMT2A::MLLT11 to intermediate risk, and to refine the risk-stratification of 9p22/KMT2A::MLLT3 AML. Future studies should validate the associations between the newly identified ACAs and outcomes and unravel the underlying biological pathogenesis of KMT2A fusions and ACAs.


Asunto(s)
N-Metiltransferasa de Histona-Lisina , Leucemia Mieloide Aguda , Proteína de la Leucemia Mieloide-Linfoide , Humanos , Proteína de la Leucemia Mieloide-Linfoide/genética , Niño , N-Metiltransferasa de Histona-Lisina/genética , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/mortalidad , Masculino , Femenino , Preescolar , Adolescente , Lactante , Pronóstico , Aberraciones Cromosómicas , Reordenamiento Génico , Estudios Retrospectivos
9.
Adv Sci (Weinh) ; 11(23): e2400870, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38553790

RESUMEN

Thermoelectric materials are highly promising for waste heat harvesting. Although thermoelectric materials research has expanded over the years, bismuth telluride-based alloys are still the best for near-room-temperature applications. In this work, a ≈38% enhancement of the average ZT (300-473 K) to 1.21 is achieved by mixing Bi0.4Sb1.6Te3 with an emerging thermoelectric material Sb2Si2Te6, which is significantly higher than that of most BiySb2-yTe3-based composites. This enhancement is facilitated by the unique interface region between the Bi0.4Sb1.6Te3 matrix and Sb2Si2Te6-based precipitates with an orderly atomic arrangement, which promotes the transport of charge carriers with minimal scattering, overcoming a common factor that is limiting ZT enhancement in such composites. At the same time, high-density dislocations in the same region can effectively scatter the phonons, decoupling the electron-phonon transport. This results in a ≈56% enhancement of the thermoelectric quality factor at 373 K, from 0.41 for the pristine sample to 0.64 for the composite sample. A single-leg device is fabricated with a high efficiency of 5.4% at ΔT = 164 K further demonstrating the efficacy of the Sb2Si2Te6 compositing strategy and the importance of the precipitate-matrix interface microstructure in improving the performance of materials for relatively low-temperature applications.

10.
Nat Mater ; 23(4): 527-534, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38454027

RESUMEN

The liquid-like feature of thermoelectric superionic conductors is a double-edged sword: the long-range migration of ions hinders the phonon transport, but their directional segregation greatly impairs the service stability. We report the synergetic enhancement in figure of merit (ZT) and stability in Cu1.99Se-based superionic conductors enabled by ion confinement effects. Guided by density functional theory and nudged elastic band simulations, we elevated the activation energy to restrict ion migrations through a cation-anion co-doping strategy. We reduced the carrier concentration without sacrificing the low thermal conductivity, obtaining a ZT of ∼3.0 at 1,050 K. Notably, the fabricated device module maintained a high conversion efficiency of up to ∼13.4% for a temperature difference of 518 K without obvious degradation after 120 cycles. Our work could be generalized to develop electrically and thermally robust functional materials with ionic migration characteristics.

11.
Front Endocrinol (Lausanne) ; 15: 1340329, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38505752

RESUMEN

Background: Identifying poor ovarian response (POR) among patients with good ovarian reserve poses a significant challenge within reproductive medicine. Currently, there is a lack of published data on the potential risk factors that could predict the occurrence of unexpected POR. The objective of this study was to develop a predictive model to assess the individual probability of unexpected POR during in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) treatments. Methods: The development of the nomogram involved a cohort of 10,404 patients with normal ovarian reserve [age, ≤40 years; antral follicle count (AFC), ≥5; and anti-Müllerian hormone (AMH), ≥1.2 ng/ml] from January 2019 to December 2022. Univariate regression analyses and least absolute shrinkage and selection operator regression analysis were employed to ascertain the characteristics associated with POR. Subsequently, the selected variables were utilized to construct the nomogram. Results: The predictors included in our model were body mass index, basal follicle-stimulating hormone, AMH, AFC, homeostasis model assessment of insulin resistance (HOMA-IR), protocol, and initial dose of gonadotropin. The area under the receiver operating characteristic curve (AUC) was 0.753 [95% confidence interval (CI) = 0.7257-0.7735]. The AUC, along with the Hosmer-Lemeshow test (p = 0.167), demonstrated a satisfactory level of congruence and discrimination ability of the developed model. Conclusion: The nomogram can anticipate the probability of unexpected POR in IVF/ICSI treatment, thereby assisting professionals in making appropriate clinical judgments and in helping patients to effectively manage expectations.


Asunto(s)
Inducción de la Ovulación , Inyecciones de Esperma Intracitoplasmáticas , Femenino , Humanos , Masculino , Adulto , Inyecciones de Esperma Intracitoplasmáticas/métodos , Inducción de la Ovulación/métodos , Semen , Fertilización In Vitro/métodos , Ovario
12.
Chem Sci ; 15(8): 2848-2856, 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38404382

RESUMEN

Crystal engineering of metal halide hybrids is critical to investigate their structure-property relationship and advance their photophysical applications, but there have been limited efforts to employ coordination chemistry to precisely control the dimensionality of metal halide sublattices. Herein, we present a coordination-assembly synthetic strategy developed for the rational modulation of lead halide dimensionality, realizing the transition from 2D to 3D architectures. This manipulation is achieved by utilizing three organocarboxylates featuring the identical cyclohexane backbone unit. Specifically, the 1,4-cyclohexanedicarboxylate and 1,2,4,5-cyclohexanetetracarboxylate ligands facilitate the formation of quasi-2D layered structures, characterized by weakly corrugated and strongly corrugated lead halide layers, respectively. Importantly, the introduction of the 1,2,3,4,5,6-cyclohexanehexacarboxylate ligand results in coordination architectures featuring 3D lead chloride/bromide sublattices. The formation of the 3D coordination architectures templated by the 1,2,3,4,5,6-cyclohexanehexacarboxylate ligand affords extended wavelength coverage and superior carrier transport properties compared to their quasi-2D layered analogues. Importantly, both the 2D and 3D lead halide-based coordination polymers exhibit high aqueous stability over a wide pH range, outperforming the conventional ionic-bound lead halides. Notably, the chemically stable 3D lead bromide exhibits efficient photocatalytic ethylbenzene oxidation with the conversion rate of 498 µmol g-1 h-1, substantially higher than its 2D lead bromide counterparts. This work highlights the important role of coordination chemistry in the rational design of metal halide hybrids, which is crucial for advancing their photophysical properties and applications.

13.
Angew Chem Int Ed Engl ; 63(16): e202316080, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38385586

RESUMEN

Lead halide hybrids have shown great potentials in CO2 photoreduction, but challenging to afford C2+ reduced products, especially using H2O as the reductant. This is largely due to the trade-off problem between instability of the benchmark 3D structures and low carrier mobility of quasi-2D analogues. Herein, the lead halide dimensionality of robust coordination polymers (CP) was modulated by organic ligands differing in a single-atom change (NH vs. CH2), in which the NH groups coordinate with interlamellar [PbI2] clusters to achieve the important 2D→3D transition. This first CP based on 3D cationic lead iodide sublattice possesses both high aqueous stability and a low exciton binding energy of 25 meV that is on the level of ambient thermal energy, achieving artificial photosynthesis of C2H5OH. Photophysical studies combined with theoretical calculations suggest the bridging [PbI2] clusters in the 3D structure not only results in enhanced carrier transport, but also promotes the intrinsic charge polarization to facilitate the C-C coupling. With trace loading of Rh cocatalyst, the apparent quantum efficiency of the 3D CP reaches 1.4 % at 400 nm with a high C2H5OH selectivity of 89.4 % (product basis), which presents one of the best photocatalysts for C2 products to date.

14.
Haematologica ; 2024 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-38186333

RESUMEN

Inotuzumab Ozogamicin (InO) is a CD22-directed antibody conjugated with calicheamicin. The Phase 1B of the ITCC-059 trial tested InO combined with chemotherapy in pediatric B-cell precursor acute lymphoblastic leukemia (BCP-ALL). Relapsed /refractory CD22+ BCP-ALL pediatric patients were enrolled. The primary objective was to establish the Recommended Phase 2 Dose (RP2D). Secondary objectives included preliminary efficacy and tolerability. InO was combined with 1.5 mg/m2 of vincristine (days 3, 10, 17, 24), 20 mg/m2 of dexamethasone (two 5-day blocks, then amended), and intrathecal therapy. A rolling-6 design was used testing InO from 0.8 to 1.8 mg/m2/cycle. Between May-2020 and Apr-2022, 30 patients were treated, and 29 were evaluable for dose limiting toxicities (DLTs). At 1.1 mg/m2/cycle, two out of four patients had DLTs (liver toxicity). InO was de-escalated to 0.8 mg/m2/cycle (n=6) without DLTs while awaiting a protocol amendment to reduce dexamethasone dose to 10 mg/m2. Post amendment, InO was re-escalated to 1.1 mg/m2/cycle (n=6, 1 DLT), then to 1.4 mg/m2/cycle (n=3, no DLTs), and finally to 1.8 mg/m2/cycle (n=7, 1 DLT). Three additional patients were treated in an expansion cohort. The pooled response rate was 80% (24/30; 95%CI: 61.4% to 92.3%) and, among responders, 66.7% achieved minimal residual disease negativity. The RP2D of InO combined with vincristine, dexamethasone and IT therapy was declared at 1.8 mg/m2/cycle (1.5 mg/m2/cycle after remission) in a fractionated schedule. This combination showed an response rate similar to the single agent cohorts of this trial, with liver toxicity issues at the initial higher dexamethasone dose. #NTR5736.

15.
Plant Biotechnol J ; 22(1): 216-232, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37792967

RESUMEN

Lipid biosynthesis and transport are essential for plant male reproduction. Compared with Arabidopsis and rice, relatively fewer maize lipid metabolic genic male-sterility (GMS) genes have been identified, and the sporopollenin metabolon in maize anther remains unknown. Here, we identified two maize GMS genes, ZmTKPR1-1 and ZmTKPR1-2, by CRISPR/Cas9 mutagenesis of 14 lipid metabolic genes with anther stage-specific expression patterns. Among them, tkpr1-1/-2 double mutants displayed complete male sterility with delayed tapetum degradation and abortive pollen. ZmTKPR1-1 and ZmTKPR1-2 encode tetraketide α-pyrone reductases and have catalytic activities in reducing tetraketide α-pyrone produced by ZmPKSB (polyketide synthase B). Several conserved catalytic sites (S128/130, Y164/166 and K168/170 in ZmTKPR1-1/-2) are essential for their enzymatic activities. Both ZmTKPR1-1 and ZmTKPR1-2 are directly activated by ZmMYB84, and their encoded proteins are localized in both the endoplasmic reticulum and nuclei. Based on protein structure prediction, molecular docking, site-directed mutagenesis and biochemical assays, the sporopollenin biosynthetic metabolon ZmPKSB-ZmTKPR1-1/-2 was identified to control pollen exine formation in maize anther. Although ZmTKPR1-1/-2 and ZmPKSB formed a protein complex, their mutants showed different, even opposite, defective phenotypes of anther cuticle and pollen exine. Our findings discover new maize GMS genes that can contribute to male-sterility line-assisted maize breeding and also provide new insights into the metabolon-regulated sporopollenin biosynthesis in maize anther.


Asunto(s)
Arabidopsis , Infertilidad , Zea mays/genética , Zea mays/metabolismo , Edición Génica , Sistemas CRISPR-Cas/genética , Simulación del Acoplamiento Molecular , Pironas/metabolismo , Fitomejoramiento , Arabidopsis/genética , Lípidos , Polen/genética , Polen/metabolismo , Infertilidad/genética , Infertilidad/metabolismo , Regulación de la Expresión Génica de las Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
16.
J Clin Oncol ; 42(7): 821-831, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38033284

RESUMEN

PURPOSE: Bosutinib is approved for adults with chronic myeloid leukemia (CML): 400 mg once daily in newly diagnosed (ND); 500 mg once daily in resistant/intolerant (R/I) patients. Bosutinib has a different tolerability profile than other tyrosine kinase inhibitors (TKIs) and potentially less impact on growth (preclinical data). The primary objective of this first-in-child trial was to determine the recommended phase II dose (RP2D) for pediatric R/I and ND patients. PATIENTS AND METHODS: In the phase I part of this international, open-label trial (ClinicalTrials.gov identifier: NCT04258943), children age 1-18 years with R/I (per European LeukemiaNet 2013) Ph+ CML were enrolled using a 6 + 4 design, testing 300, 350, and 400 mg/m2 once daily with food. The RP2D was the dose resulting in 0/6 or 1/10 dose-limiting toxicities (DLTs) during the first cycle and achieving adult target AUC levels for the respective indication. As ND participants were only enrolled in phase II, the ND RP2D was selected based on data from R/I patients. RESULTS: Thirty patients were enrolled; 27 were evaluable for DLT: six at 300 mg/m2, 11 at 350 mg/m2 (one DLT), and 10 at 400 mg/m2 (one DLT). The mean AUCs at 300 mg/m2, 350 mg/m2, and 400 mg/m2 were 2.20 µg h/mL, 2.52 µg h/mL, and 2.66 µg h/mL, respectively. The most common adverse event was diarrhea (93%; ≥grade 3: 11%). Seven patients stopped because of intolerance and eight because of insufficient response. Complete cytogenetic and major molecular response to bosutinib appeared comparable with other published phase I/II trials with second-generation TKIs in children. CONCLUSION: Bosutinib was safe and effective. The pediatric RP2D was 400 mg/m2 once daily (max 600 mg/d) with food in R/I patients and 300 mg/m2 once daily (max 500 mg/d) with food in ND patients, which achieved targeted exposures as per adult experience.


Asunto(s)
Antineoplásicos , Leucemia Mielógena Crónica BCR-ABL Positiva , Leucemia Mieloide de Fase Crónica , Quinolinas , Adolescente , Adulto , Niño , Preescolar , Humanos , Lactante , Compuestos de Anilina/efectos adversos , Antineoplásicos/efectos adversos , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Leucemia Mieloide de Fase Crónica/tratamiento farmacológico , Nitrilos/efectos adversos , Inhibidores de Proteínas Quinasas/efectos adversos , Quinolinas/efectos adversos , Resultado del Tratamiento
17.
Front Endocrinol (Lausanne) ; 14: 1238092, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38047110

RESUMEN

Backgrounds: The present study was designed to establish and validate a prediction model for high ovarian response (HOR) in the GnRH antagonist protocol. Methods: In this retrospective study, the data of 4160 cycles were analyzed following the in vitro fertilization (IVF) at our reproductive medical center from June 2018 to May 2022. The cycles were divided into a training cohort (n=3121) and a validation cohort (n=1039) using a random sampling method. Univariate and multivariate logistic regression analyses were used to screen out the risk factors for HOR, and the nomogram was established based on the regression coefficient of the relevant variables. The area under the receiver operating characteristic curve (AUC), the calibration curve, and the decision curve analysis were used to evaluate the performance of the prediction model. Results: Multivariate logistic regression analysis revealed that age, body mass index (BMI), follicle-stimulating hormone (FSH), antral follicle count (AFC), and anti-mullerian hormone (AMH) were independent risk factors for HOR (all P< 0.05). The prediction model for HOR was constructed based on these factors. The AUC of the training cohort was 0.884 (95% CI: 0.869-0.899), and the AUC of the validation cohort was 0.884 (95% CI:0.863-0.905). Conclusion: The prediction model can predict the probability of high ovarian response prior to IVF treatment, enabling clinicians to better predict the risk of HOR and guide treatment strategies.


Asunto(s)
Ovario , Inducción de la Ovulación , Femenino , Humanos , Resultado del Tratamiento , Estudios Retrospectivos , Inducción de la Ovulación/métodos , Hormona Liberadora de Gonadotropina
18.
Nat Commun ; 14(1): 7428, 2023 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-37973881

RESUMEN

Mg3(Sb,Bi)2 is a promising thermoelectric material suited for electronic cooling, but there is still room to optimize its low-temperature performance. This work realizes >200% enhancement in room-temperature zT by incorporating metallic inclusions (Nb or Ta) into the Mg3(Sb,Bi)2-based matrix. The electrical conductivity is boosted in the range of 300-450 K, whereas the corresponding Seebeck coefficients remain unchanged, leading to an exceptionally high room-temperature power factor >30 µW cm-1 K-2; such an unusual effect originates mainly from the modified interfacial barriers. The reduced interfacial barriers are conducive to carrier transport at low and high temperatures. Furthermore, benefiting from the reduced lattice thermal conductivity, a record-high average zT > 1.5 and a maximum zT of 2.04 at 798 K are achieved, resulting in a high thermoelectric conversion efficiency of 15%. This work demonstrates an efficient nanocomposite strategy to enhance the wide-temperature-range thermoelectric performance of n-type Mg3(Sb,Bi)2, broadening their potential for practical applications.

19.
Inorg Chem ; 62(43): 17905-17912, 2023 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-37843461

RESUMEN

Thermoelectric sulfide materials are of particular interest due to the earth-abundant and cost-effective nature of sulfur. Here, we report a new n-type degenerate semiconductor sulfide, AgBiPbS3, which adopts a Fm3̅m structure with a narrow band gap of ∼0.32 eV. Despite the homogeneous distribution of elements at the scale of micrometer, Ag2S nanoprecipitates with dimensions of several nanometers were detected throughout the matrix. AgBiPbS3 exhibits a low room-temperature lattice thermal conductivity of 0.88 W m-1 K-1, owing to the intrinsic low lattice thermal conductivity of Ag2S and the effective scattering of phonons at nanoprecipitate boundaries. Moreover, compared to AgBiS2, AgBiPbS3 demonstrates a significantly improved weighted mobility of >16 cm2 V-1 s-1 at 300 K, leading to an enhanced PF of 1.6 µW cm-1 K-2 at 300 K. The superior electrical transport in AgBiPbS3 can be attributed to the high valley degeneracy of the L point (the conduction band minimum), which is contributed by the Pb s and Pb p orbitals. Further, Ga doping is found to be effective in modulating the Fermi levels of AgBiPbS3, leading to further enhancement of PF with a PFave of 2.7 µW cm-1 K-2 in the temperature range of 300-823 K. Consequently, a relatively high ZTave of 0.22 and a peak ZT of ∼0.4 at 823 K have been achieved in 3% Ga-doped AgBiPbS3, highlighting the potential of AgBiPbS3 as an n-type thermoelectric sulfide.

20.
J Electrocardiol ; 81: 230-236, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37844372

RESUMEN

BACKGROUND: Atrial fibrillation (AF) is a cause of serious morbidity such as stroke. Early detection and treatment of AF is important. Current guidelines recommend screening via opportunistic pulse taking or 12­lead electrocardiogram. Mid-term ECG patch monitors increases the sensitivity of AF detection. METHODS: The Singapore Atrial Fibrillation Study is a prospective multi-centre study aiming to study the incidence of AF in patients with no prior AF and a CHA2DS2-VASc score of at least 1, with the use of a mid-term continuous ECG monitoring device (Spyder ECG). Consecutive patients from both inpatient and outpatient settings were recruited from 3 major hospitals from May 2016 to December 2019. RESULTS: Three hundred and fifty-five patients were monitored. 6 patients (1.7%) were diagnosed with AF. There were no significant differences in total duration of monitoring between the AF and non-AF group (6.39 ± 3.19 vs 5.42 ± 2.46 days, p = 0.340). Patients with newly detected AF were more likely to have palpitations (50.0% vs 11.8%, p = 0.027). Half of the patients (n = 3, 50.0%) were diagnosed on the first day of monitoring and the rest were diagnosed after 24 h. On univariate analysis, only hyperlipidemia was associated with reduced odds of being diagnosed with AF (OR HR 0.08 CI 0.01-0.74, p = 0.025). In a group of 128 patients who underwent coronary artery bypass grafting and had post-operative ECG monitoring, 9 patients (7.0%) were diagnosed with post-operative AF. CONCLUSIONS: The use of non-invasive mid-term patch-based ECG monitoring is an effective modality for AF screening.


Asunto(s)
Fibrilación Atrial , Accidente Cerebrovascular , Humanos , Electrocardiografía , Estudios Prospectivos , Tamizaje Masivo
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