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1.
Nature ; 632(8025): 528-535, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39048826

RESUMO

Conjugated polymers promise inherently flexible and low-cost thermoelectrics for powering the Internet of Things from waste heat1,2. Their valuable applications, however, have been hitherto hindered by the low dimensionless figure of merit (ZT)3-6. Here we report high-ZT thermoelectric plastics, which were achieved by creating a polymeric multi-heterojunction with periodic dual-heterojunction features, where each period is composed of two polymers with a sub-ten-nanometre layered heterojunction structure and an interpenetrating bulk-heterojunction interface. This geometry produces significantly enhanced interfacial phonon-like scattering while maintaining efficient charge transport. We observed a significant suppression of thermal conductivity by over 60 per cent and an enhanced power factor when compared with individual polymers, resulting in a ZT of up to 1.28 at 368 kelvin. This polymeric thermoelectric performance surpasses that of commercial thermoelectric materials and existing flexible thermoelectric candidates. Importantly, we demonstrated the compatibility of the polymeric multi-heterojunction structure with solution coating techniques for satisfying the demand for large-area plastic thermoelectrics, which paves the way for polymeric multi-heterojunctions towards cost-effective wearable thermoelectric technologies.

2.
Proc Natl Acad Sci U S A ; 121(3): e2312680121, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38194462

RESUMO

Periodic spin-orbit motion is ubiquitous in nature, observed from electrons orbiting nuclei to spinning planets orbiting the Sun. Achieving autonomous periodic orbiting motions, along circular and noncircular paths, in soft mobile robotics is crucial for adaptive and intelligent exploration of unknown environments-a grand challenge yet to be accomplished. Here, we report leveraging a closed-loop twisted ring topology with a defect for an autonomous soft robot capable of achieving periodic spin-orbiting motions with programmed circular and re-programmed irregular-shaped trajectories. Constructed by bonding a twisted liquid crystal elastomer ribbon into a closed-loop ring topology, the robot exhibits three coupled periodic self-motions in response to constant temperature or constant light sources: inside-out flipping, self-spinning around the ring center, and self-orbiting around a point outside the ring. The coupled spinning and orbiting motions share the same direction and period. The spinning or orbiting direction depends on the twisting chirality, while the orbital radius and period are determined by the twisted ring geometry and thermal actuation. The flip-spin and orbiting motions arise from the twisted ring topology and a bonding site defect that breaks the force symmetry, respectively. By utilizing the twisting-encoded autonomous flip-spin-orbit motions, we showcase the robot's potential for intelligently mapping the geometric boundaries of unknown confined spaces, including convex shapes like circles, squares, triangles, and pentagons and concaves shapes with multi-robots, as well as health monitoring of unknown confined spaces with boundary damages.

3.
Proc Natl Acad Sci U S A ; 121(14): e2316564121, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38527200

RESUMO

Sulfur in nature consists of two abundant stable isotopes, with two more neutrons in the heavy one (34S) than in the light one (32S). The two isotopes show similar physicochemical properties and are usually considered an integral system for chemical research in various fields. In this work, a model study based on a Li-S battery was performed to reveal the variation between the electrochemical properties of the two S isotopes. Provided with the same octatomic ring structure, the cyclo-34S8 molecules form stronger S-S bonds than cyclo-32S8 and are more prone to react with Li. The soluble Li polysulfides generated by the Li-34S conversion reaction show a stronger cation-solvent interaction yet a weaker cation-anion interaction than the 32S-based counterparts, which facilitates quick solvation of polysulfides yet hinders their migration from the cathode to the anode. Consequently, the Li-34S cell shows improved cathode reaction kinetics at the solid-liquid interface and inhibited shuttle of polysulfides through the electrolyte so that it demonstrates better cycling performance than the Li-32S cell. Based on the varied shuttle kinetics of the isotopic-S-based polysulfides, an electrochemical separation method for 34S/32S isotope is proposed, which enables a notably higher separation factor than the conventional separation methods via chemical exchange or distillation and brings opportunities to low-cost manufacture, utilization, and research of heavy chalcogen isotopes.

4.
Cell Mol Life Sci ; 81(1): 254, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38856931

RESUMO

The endogenous mitochondrial quality control (MQC) system serves to protect mitochondria against cellular stressors. Although mitochondrial dysfunction contributes to cardiac damage during many pathological conditions, the regulatory signals influencing MQC disruption during septic cardiomyopathy (SC) remain unclear. This study aimed to investigate the involvement of pyruvate kinase M2 (PKM2) and prohibitin 2 (PHB2) interaction followed by MQC impairment in the pathogenesis of SC. We utilized LPS-induced SC models in PKM2 transgenic (PKM2TG) mice, PHB2S91D-knockin mice, and PKM2-overexpressing HL-1 cardiomyocytes. After LPS-induced SC, cardiac PKM2 expression was significantly downregulated in wild-type mice, whereas PKM2 overexpression in vivo sustained heart function, suppressed myocardial inflammation, and attenuated cardiomyocyte death. PKM2 overexpression relieved sepsis-related mitochondrial damage via MQC normalization, evidenced by balanced mitochondrial fission/fusion, activated mitophagy, restored mitochondrial biogenesis, and inhibited mitochondrial unfolded protein response. Docking simulations, co-IP, and domain deletion mutant protein transfection experiments showed that PKM2 phosphorylates PHB2 at Ser91, preventing LPS-mediated PHB2 degradation. Additionally, the A domain of PKM2 and the PHB domain of PHB2 are required for PKM2-PHB2 binding and PHB2 phosphorylation. After LPS exposure, expression of a phosphorylation-defective PHB2S91A mutant negated the protective effects of PKM2 overexpression. Moreover, knockin mice expressing a phosphorylation-mimetic PHB2S91D mutant showed improved heart function, reduced inflammation, and preserved mitochondrial function following sepsis induction. Abundant PKM2 expression is a prerequisite to sustain PKM2-PHB2 interaction which is a key element for preservation of PHB2 phosphorylation and MQC, presenting novel interventive targets for the treatment of septic cardiomyopathy.


Assuntos
Cardiomiopatias , Miócitos Cardíacos , Proibitinas , Piruvato Quinase , Proteínas Repressoras , Sepse , Animais , Fosforilação , Cardiomiopatias/metabolismo , Cardiomiopatias/patologia , Camundongos , Piruvato Quinase/metabolismo , Piruvato Quinase/genética , Sepse/metabolismo , Proteínas Repressoras/metabolismo , Proteínas Repressoras/genética , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Mitocôndrias Cardíacas/metabolismo , Camundongos Transgênicos , Camundongos Endogâmicos C57BL , Masculino , Lipopolissacarídeos , Humanos , Mitofagia
5.
J Cell Physiol ; 239(6): e31272, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38646844

RESUMO

The inhibition of cell surface crystal adhesion and an appropriate increase in crystal endocytosis contribute to the inhibition of kidney stone formation. In this study, we investigated the effects of different degrees of carboxymethylation on these processes. An injury model was established by treating human renal proximal tubular epithelial (HK-2) cells with 98.3 ± 8.1 nm calcium oxalate dihydrate (nanoCOD) crystals. The HK-2 cells were protected with carboxy (-COOH) Desmodium styracifolium polysaccharides at 1.17% (DSP0), 7.45% (CDSP1), 12.2% (CDSP2), and 17.7% (CDSP3). Changes in biochemical indexes and effects on nanoCOD adhesion and endocytosis were detected. The protection of HK-2 cells from nanoCOD-induced oxidative damage by carboxymethylated Desmodium styracifolium polysaccharides (CDSPs) is closely related to the protection of subcellular organelles, such as mitochondria. CDSPs can reduce crystal adhesion on the cell surface and maintain appropriate crystal endocytosis, thereby reducing the risk of kidney stone formation. CDSP2 with moderate -COOH content showed the strongest protective activity among the CDSPs.


Assuntos
Oxalato de Cálcio , Endocitose , Cálculos Renais , Polissacarídeos , Humanos , Oxalato de Cálcio/metabolismo , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Cristalização , Endocitose/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Cálculos Renais/prevenção & controle , Cálculos Renais/tratamento farmacológico , Túbulos Renais Proximais/efeitos dos fármacos , Túbulos Renais Proximais/patologia , Túbulos Renais Proximais/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Polissacarídeos/farmacologia , Polissacarídeos/química , Sobrevivência Celular/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Cálcio/metabolismo , Espaço Intracelular/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos
6.
Neuroimage ; 289: 120551, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38382862

RESUMO

It has been revealed that abnormal voxel-mirrored homotopic connectivity (VMHC) is present in patients with schizophrenia, yet there are inconsistencies in the relevant findings. Moreover, little is known about their association with brain gene expression profiles. In this study, transcription-neuroimaging association analyses using gene expression data from Allen Human Brain Atlas and case-control VMHC differences from both the discovery (meta-analysis, including 9 studies with a total of 386 patients and 357 controls) and replication (separate group-level comparisons within two datasets, including a total of 258 patients and 287 controls) phases were performed to identify genes associated with VMHC alterations. Enrichment analyses were conducted to characterize the biological functions and specific expression of identified genes, and Neurosynth decoding analysis was performed to examine the correlation between cognitive-related processes and VMHC alterations in schizophrenia. In the discovery and replication phases, patients with schizophrenia exhibited consistent VMHC changes compared to controls, which were correlated with a series of cognitive-related processes; meta-regression analysis revealed that illness duration was negatively correlated with VMHC abnormalities in the cerebellum and postcentral/precentral gyrus. The abnormal VMHC patterns were stably correlated with 1287 genes enriched for fundamental biological processes like regulation of cell communication, nervous system development, and cell communication. In addition, these genes were overexpressed in astrocytes and immune cells, enriched in extensive cortical regions and wide developmental time windows. The present findings may contribute to a more comprehensive understanding of the molecular mechanisms underlying VMHC alterations in patients with schizophrenia.


Assuntos
Esquizofrenia , Humanos , Esquizofrenia/diagnóstico por imagem , Esquizofrenia/genética , Imageamento por Ressonância Magnética , Encéfalo , Mapeamento Encefálico , Expressão Gênica
7.
Chembiochem ; 25(12): e202400105, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38639074

RESUMO

Cell senescence is defined as irreversible cell cycle arrest, which can be triggered by telomere shortening or by various types of genotoxic stress. Induction of senescence is emerging as a new strategy for the treatment of cancer, especially when sequentially combined with a second senolytic drug capable of killing the resulting senescent cells, however severely suffering from the undesired off-target side effects from the senolytic drugs. Here, we prepare a bimetalic platinum-aluminum salen complex (Alumiplatin) for cancer therapy-a combination of pro-senesence chemotherapy with in situ senotherapy to avoid the side effects. The aluminum salen moiety, as a G-quadruplex stabilizer, enhances the salen's ability to induce cancer cell senescence and this phenotype is in turn sensitive to the cytotoxic activity of the monofunctional platinum moiety. It exhibits an excellent capability for inducing senescence, a potent cytotoxic activity against cancer cells both in vitro and in vivo, and an improved safety profile compared to cisplatin. Therefore, Alumiplatin may be a good candidate to be further developed into safe and effective anticancer agents. This novel combination of cell senescence inducers with genotoxic drugs revolutionizes the therapy options of designing multi-targeting anticancer agents to improve the efficacy of anticancer therapies.


Assuntos
Alumínio , Antineoplásicos , Senescência Celular , Etilenodiaminas , Platina , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/química , Etilenodiaminas/química , Etilenodiaminas/farmacologia , Senescência Celular/efeitos dos fármacos , Platina/química , Platina/farmacologia , Alumínio/química , Alumínio/farmacologia , Animais , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Complexos de Coordenação/uso terapêutico , Camundongos , Proliferação de Células/efeitos dos fármacos , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Compostos Organoplatínicos/farmacologia , Compostos Organoplatínicos/química
8.
J Transl Med ; 22(1): 338, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594692

RESUMO

BACKGROUND: SIRPB1 expression is upregulated in various tumor types, including gliomas, and is known to contribute to tumor progression; nevertheless, its function in the immune milieu of gliomas is still mainly unknown. METHODS: This study, we analyzed 1152 normal samples from the GTEx database and 670 glioma samples from the TCGA database to investigate the relationship between the expression of SIRPB1 and clinicopathological features. Moreover, SIRPB1 gene knockout THP-1 cell lines were constructed using CRISPR/Cas9 and were induced into a co-culture of macrophages and glioma cells in vitro to learn more about the role of SIRPB1 in the glioma immune milieu. Lastly, we established a prognostic model to predict the effect of SIRPB1 on prognosis. RESULTS: Significantly higher levels of SIRPB1 expression were found in gliomas, which had an adverse effect on the immune milieu and correlated poorly with patient survival. SIRPB1 activation with certain antibodies results in SYK phosphorylation and the subsequent activation of calcium, MAPK, and NF-κB signaling pathways. This phenomenon is primarily observed in myeloid-derived cells as opposed to glioma cells. In vitro co-culture demonstrated that macrophages with SIRPB1 knockout showed decreased IL1RA, CCL2, and IL-8, which were recovered upon ectopic expression of SIRPB1 but reduced again following treatment with SYK inhibitor GS9973. Critically, a lower overall survival rate was linked to increased SIRPB1 expression. Making use of SIRPB1 expression along with additional clinicopathological variables, we established a nomogram that showed a high degree of prediction accuracy. CONCLUSIONS: Our study demonstrates that glioma cells can be activated by macrophages via SIRPB1, subsequently reprogramming the TME, suggesting that SIRPB1 could serve as a promising therapeutic target for gliomas.


Assuntos
Anticorpos , Glioma , Humanos , Cálcio , Técnicas de Cocultura , Biologia Computacional , Glioma/genética , Quinase Syk/genética , Microambiente Tumoral
9.
Cardiovasc Diabetol ; 23(1): 111, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38555461

RESUMO

BACKGROUND: The triglyceride and glucose (TyG) index, a simple surrogate marker of insulin resistance, is related to cardiovascular disease. However, there is a lack of evidence for the relationship between the TyG index and chest pain. This study aimed to investigate the association of the TyG index with chest pain and to evaluate the relationship between the TyG index and all-cause mortality in participants with or without chest pain. METHODS: The present study utilized data from the 2001-2012 National Health and Nutrition Examination Survey (NHANES), employing a combination of cross-sectional and cohort study designs. The association between the TyG index and chest pain was investigated using weighted logistic regression models. Weighted Cox proportional hazards models were used to estimate the hazard ratios (HRs) and 95% confidence intervals (95% CIs) for all-cause mortality. Restricted cubic spline analysis was used to explore linear or nonlinear relationships between the TyG index and chest pain or all-cause mortality. RESULTS: The findings revealed a positive correlation between the TyG index and chest pain, even after adjusting for potential confounding factors (quartile 4 versus quartile 1, odds ratio [OR] 1.42, 95% confidence interval [CI] 1.14-1.77, P = 0.002). During a mean follow-up time of 139 months, a total of 2286 individuals (27.43%) experienced mortality. Weighted multivariate Cox regression models indicated that for each one-unit increase in the TyG index, the adjusted hazard ratio (HR) for mortality was 1.14 (95% CI = 0.94-1.37) for participants with chest pain and 1.25 (95% CI = 1.09-1.43) for those without chest pain. Furthermore, restricted cubic spline analysis revealed a linear relationship between the TyG index and chest pain (P for nonlinearity = 0.902), whereas a nonlinear relationship was shown between the TyG index and all-cause mortality among populations regardless of chest pain (all P for nonlinearity < 0.01). CONCLUSION: The TyG index was positively linked to a higher incidence of chest pain. Moreover, the TyG index was associated with all-cause mortality not only in participants with chest pain but also in those without chest pain.


Assuntos
Dor no Peito , Glucose , Humanos , Estudos de Coortes , Estudos Transversais , Incidência , Inquéritos Nutricionais , Dor no Peito/diagnóstico , Triglicerídeos
10.
Rev Cardiovasc Med ; 25(1): 10, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-39077666

RESUMO

Background: The combination of left atrial appendage closure (LAAC) and catheter ablation (CA) in a single procedure is a safe and effective form of treatment for atrial fibrillation (AF). However, several findings have argued that LAAC might increase the risk of AF recurring. Therefore, this study investigated the impact of insufficient ablation on AF recurrence after the hybrid procedures of CA and LAAC. Methods: We reviewed 107 consecutive patients with AF who received the CA and LAAC hybrid procedures (combined group). In the case-control study, another 107 patients who underwent only CA (ablation group) were successfully matched using propensity score matching. After correcting the insufficient ablation, 107 consecutive patients were enrolled prospectively. During the follow-up period, postprocedural 24-hour monitor recordings and a portable electrocardiogram (ECG) monitoring device were used to detect AF recurrence. Transesophageal echocardiography was used to evaluate LAAC. Results: The combined group showed an increase in the risk of AF recurrence after 539.2 ± 304.4 days of follow-up (29.9% vs. 15.9%, p < 0.05). Interestingly, the duration of the procedure was not significantly prolonged when LAAC was added after CA in the combined group, while there was a higher number of ablating attempts, duration of ablation, and additional ablation in the ablation group for both radiofrequency and cryoballoon ablation. After correcting for the insufficient ablation, the corrected group showed a significant decrease in AF recurrence after 420.4 ± 204.8 days of follow-up. Conclusions: Insufficient ablation is common when combining CA and LAAC and may lead to the recurrence of atrial fibrillation. It should be corrected intentionally by sufficient ablation of the pulmonary vein antrum and additional ablation. Clinical Trial Registration: The prospective study is a sub-study of our CAGEDAF study that has already been registered (ChiCTR2000039746).

11.
Phys Rev Lett ; 132(3): 035102, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38307060

RESUMO

We report the first experimental observation on the reduction of backward scatterings by an instantaneous broadband laser with 0.6% bandwidth in conditions of interest for inertial confinement fusion at the low-coherence Kunwu laser facility. The backscatter of stimulated Brillouin scattering (SBS) was robustly reduced by half at intensities of 1-5×10^{14} W/cm^{2} with the 0.53-µm broadband laser in comparison with the monochromatic laser. As SBS dominates energy loss of laser-plasma interactions, the reduction of that demonstrates the enhancement of laser-target coupling by the use of broadband laser. The mitigation of filamentation leads to the reduction of stimulated Raman backscattering at low intensities. In addition, the three-halves harmonic emission was reduced with the broadband laser as well.

12.
Wound Repair Regen ; 32(3): 279-291, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38353052

RESUMO

Pressure ulcer (PU) is a worldwide problem that is difficult to address because of the related inflammatory response, local hypoxia, and repeated ischaemia/reperfusion, causing great suffering and financial burden to patients. Traditional Chinese medicine turtle plate powder can treat skin trauma, but its composition is complex and inconvenient to use. Here, we combined cholesterol myristate (S8) with berberine (BBR), with anti-inflammatory and antibacterial effects, as a drug and used hydroxypropyl methylcellulose and polyvinylpyrrolidone K30 as carriers to construct a novel film-forming polymeric solution (S8 + BBR FFPS), comprehensively study its reparative effect on PU and explore the potential mechanism in rat PU models. The results showed that S8 + BBR FFPS inhibits excessive inflammatory response, promotes re-epithelialization, and promotes hair follicle growth during the healing process of PU, which may be related to the activation of the Wnt/ß-catenin signalling pathway by S8 + BBR FFPS to mediate hair follicle stem cell proliferation and maintain skin homeostasis. Therefore, S8 + BBR FFPS may be a potential candidate for the treatment of chronic skin injury, and its association with the Wnt/ß-catenin signalling pathway may provide new ideas to guide the design of biomaterial-based wound dressings for chronic wound repair.


Assuntos
Berberina , Modelos Animais de Doenças , Úlcera por Pressão , Ratos Sprague-Dawley , Via de Sinalização Wnt , Cicatrização , Animais , Úlcera por Pressão/tratamento farmacológico , Berberina/farmacologia , Berberina/uso terapêutico , Ratos , Cicatrização/efeitos dos fármacos , Via de Sinalização Wnt/efeitos dos fármacos , Masculino , Polímeros/farmacologia , Proliferação de Células/efeitos dos fármacos
13.
Analyst ; 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39176451

RESUMO

Correction for 'Open-flow microperfusion combined with mass spectrometry for in vivo liver lipidomic analysis' by Tuo Li et al., Analyst, 2021, 146, 1915-1923, https://doi.org/10.1039/D0AN02189J.

14.
Inorg Chem ; 63(4): 1879-1887, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38240218

RESUMO

The development of efficient fluorescent probes and adsorbents for detecting and removing Cu2+, which pose potential environmental and health risks, is a highly active area of research. However, achieving simultaneously improved fluorescence detection efficiency and enhanced adsorption capacity in a single porous probe remains a significant challenge. In this study, we successfully synthesized a two-dimensional imine-based TAP-COF using 2,4,6-triformylphloroglucinol and tri(4-aminophenyl)amine as raw materials. TAP-COF exhibited excellent properties, including a large specific surface area of 685.65 m2·g-1, exceptional thermal stability (>440 °C), chemical stability, temporal stability, and recyclability. Fluorescence testing revealed that TAP-COF exhibited remarkable specificity and high sensitivity for detecting Cu2+. The fluorescence mechanism, in which the excited state intramolecular proton transfer was impeded by the interaction of Cu2+ with C═O and C-N bonds on TAP-COF upon the addition of Cu2+, was further elucidated through experimental and theoretical methods. Furthermore, the adsorption capacity of TAP-COF toward Cu2+ was investigated, confirming the excellence of TAP-COF as a fluorescent probe and adsorbent for the specific detection and removal of Cu2+. This work holds significant implications for improving environmental and human health concerns associated with Cu2+ contamination.

15.
Mol Biol Rep ; 51(1): 602, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38698158

RESUMO

BACKGROUND: Low-temperature severely limits the growth and development of Camellia oleifera (C. oleifera). The mitogen-activated protein kinase (MAPK) cascade plays a key role in the response to cold stress. METHODS AND RESULTS: Our study aims to identify MAPK cascade genes in C. oleifera and reveal their roles in response to cold stress. In our study, we systematically identified and analyzed the MAPK cascade gene families of C. oleifera, including their physical and chemical properties, conserved motifs, and multiple sequence alignments. In addition, we characterized the interacting networks of MAPKK kinase (MAPKKK)-MAPK kinase (MAPKK)-MAPK in C. oleifera. The molecular mechanism of cold stress resistance of MAPK cascade genes in wild C. oleifera was analyzed by differential gene expression and real-time quantitative reverse transcription-PCR (qRT-PCR). CONCLUSION: In this study, 21 MAPKs, 4 MAPKKs and 55 MAPKKKs genes were identified in the leaf transcriptome of C. oleifera. According to the phylogenetic results, MAPKs were divided into 4 groups (A, B, C and D), MAPKKs were divided into 3 groups (A, B and D), and MAPKKKs were divided into 2 groups (MEKK and Raf). Motif analysis showed that the motifs in each subfamily were conserved, and most of the motifs in the same subfamily were basically the same. The protein interaction network based on Arabidopsis thaliana (A. thaliana) homologs revealed that MAPK, MAPKK, and MAPKKK genes were widely involved in C. oleifera growth and development and in responses to biotic and abiotic stresses. Gene expression analysis revealed that the CoMAPKKK5/CoMAPKKK43/CoMAPKKK49-CoMAPKK4-CoMAPK8 module may play a key role in the cold stress resistance of wild C. oleifera at a high-elevation site in Lu Mountain (LSG). This study can facilitate the mining and utilization of genetic resources of C. oleifera with low-temperature tolerance.


Assuntos
Camellia , Resposta ao Choque Frio , Regulação da Expressão Gênica de Plantas , Filogenia , Proteínas de Plantas , Resposta ao Choque Frio/genética , Camellia/genética , Regulação da Expressão Gênica de Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Sistema de Sinalização das MAP Quinases/genética , Temperatura Baixa , Transcriptoma/genética , Família Multigênica , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Perfilação da Expressão Gênica/métodos , Folhas de Planta/genética
16.
Phys Chem Chem Phys ; 26(9): 7318-7328, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38352998

RESUMO

Density functional theory, in conjunction with the quasi-harmonic approximation, has been used to study the equilibrium between the orthorhombic and tetragonal phases of Ba3Ge4. A transition from the high-temperature tetragonal phase containing isolated Ge46- units to the low-temperature orthorhombic phase, where precisely half of the Ge46- units are polymerised along one axis, is predicted at 930 K, somewhat higher than the experimental value of 630 K. An analysis of the phonon density of states shows that the lower entropy of the orthorhombic phase is not associated directly with the polymerisation of the Ge46- units, but rather with the contraction of the unit cell, which raises the frequencies of ion-ion modes involving the relative motions of the Ba2+ and Ge46- units. Calculations also predict that a third, as yet unobserved, p-tetragonal phase, where all of the Ge46- units are polymerised to form two separate chains running in orthogonal directions, might be accessible at pressures close to 1 GPa.

17.
Artigo em Inglês | MEDLINE | ID: mdl-38401088

RESUMO

Background: Lumbar spondylolysis (LS) poses a potential threat, and there is a need to evaluate and compare the effectiveness of direct pars repair techniques. Objective: To assess and compare the clinical and radiographic outcomes of direct pars repair techniques using the pedicle screw hook system (PSHS) and the pedicle screw rod system (PSRS) in young symptomatic patients with lumbar spondylolysis. Methods: A retrospective study was conducted to compare clinical and radiological data in young symptomatic LS patients after surgery. Records of 45 post-surgery LS patients with a minimum 24-month follow-up (January 2014 to June 2019) were reviewed. A total of 26 patients underwent PSHS, and 19 had PSRS. Treatment outcomes were analyzed using the visual analog pain scale (VAS), Oswestry disability index (ODI), MacNab criteria, lumbar fusion status, and Pfirrmann grading standards. Patient baseline characteristics were also compared between the two groups. Results: No disc degeneration was observed in either PSHS or PSRS groups at 24 months postoperatively, according to the Pfirrmann grading scale. The PSRS group outperformed the PSHS group in operative time, intraoperative blood loss, postoperative drainage, length of hospital stays, ODI, VAS values at 3 months postoperatively, and fusion status at 6 months postoperatively. No notable differences were observed in other parameters during the 24-month follow-up period, and no significant surgical complications were recorded. Conclusions: Direct pars repair techniques using PSHS and PSRS yielded satisfactory clinical and radiographic results in young patients with symptomatic LS. PSRS, compared to PSHS, demonstrated greater effectiveness in young individuals with LS and promoted early recovery.

18.
Plant Dis ; 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38831590

RESUMO

Pumpkin (Cucurbita moschata), which belongs to the gourd family (Cucurbitaceae), is widely planted throughout the world. In June 2023, many pumpkin plants (cv. Miben) displayed leaf blight and chlorosis in fields located in Suizhou (31.99°N, 113.02°E), Hubei Province, China. The disease incidence ranged from 30 to 40% in nine fields, 6.3 ha in total. The symptoms were irregularly shaped lesions that expanded along the mid-vein until the leaf turned brown and wilted. Fungal isolations were performed as described previously (Liu et al. 2023). Twenty pumpkin leaf samples with typical symptoms were collected and cut into 1 cm×1 cm pieces. The diseased tissue was surface-sterilized in 75% ethanol for 30 sec, plated on potato dextrose agar (PDA) medium and incubated at 25℃ for 3 days. Then, the emerging single fungal hyphal tip was transferred onto PDA plates to obtain purified isolates. A total of eighteen isolates on PDA plates were initially white and then developed to dark gray. The 5-day-old cultures growing on mung bean medium produced conidia that were black, single-celled, smooth, spherical or oblate, and ranged in size from 14.5 to 20.8 µm×13.3 to 20.5 µm (n=50). Therefore, the isolates were morphologically identified as Nigrospora sphaerica. Moreover, the genomic DNA of the isolates (HB-P1,HB-P2, and HB-P3) was extracted for amplification and sequencing of the regions of internal transcribed spacer (ITS) (White et al. 1990), nuclear large subunit rRNA (nLSU) (O'Donnell 1992; Rehner and Samuels 1994), and ß-tubulin (TUB2) (Glass and Donaldson 1995), with primers ITS1/ITS4, LROR/LR3, and Bt2a/Bt2b, respectively. Sequences were submitted to GenBank under accession numbers PP348112, PP348113, PP348114 (ITS), PP411414, PP411415, PP411416 (nLSU), and PP357438, PP357439, PP357440 (TUB2). BLASTn showed that the sequences ITS, nLSU, and TUB2 of HB-P1, HB-P2, and HB-P3 had >99% nucleotide identities ((ITS: 100%, 508/508 bp, MF996488.1; 99.8%, 506/507, ON326588.1; 100%, 500/500 ,MK748317.1), (nLSU: 99.83%, 573/574, KT462720.1; 99.83% , 574/575 bp, KT462720.1; 99.65%, 575/577, KT462720.1), and (TUB2: 100%, 388/388, MN719407.1; 99.74%, 387/388, MN719407.1; 100%, 387/387, MN719407.1)) with Nigrospora sphaerica, respectively. A multilocus (ITS, nLSU and TUB2) phylogenetic analysis indicated that the isolates were Nigrospora sphaerica. Pathogenicity of three isolates were tested on pumpkin plants (cv. Miben). Fifteen pumpkin plants were inoculated by spraying the leaves (1×106 spores/ml), respectively, and 10 pumpkin plants were treated with sterile water as a negative control. All plants were incubated in an artificial climate box (LongYue, ShangHai) at 25℃ for 12 days. The experiment was repeated three times. Twelve days later, the inoculated pumpkin plants developed symptoms of leaf blight, while the control plants remained healthy. Then, pathogens were re-isolated from the each leaf of inoculated pumpkin plants and not from the control plants. Nigrospora sphaerica has been previously reported to cause leaf spot on watermelon in Malaysia (Ismail and Abd Razak 2021). To our knowledge, this is the first report of N. sphaerica causing leaf blight on pumpkin in China. This new disease can cause leaf blight, which may affect pumpkin productivity.

19.
J Appl Clin Med Phys ; 25(4): e14259, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38317597

RESUMO

BACKGROUND: The treatment planning process from segmentation to producing a deliverable plan is time-consuming and labor-intensive. Existing solutions automate the segmentation and planning processes individually. The feasibility of combining auto-segmentation and auto-planning for volumetric modulated arc therapy (VMAT) for rectal cancers in an end-to-end process is not clear. PURPOSE: To create and clinically evaluate a complete end-to-end process for auto-segmentation and auto-planning of VMAT for rectal cancer requiring only the gross tumor volume contour and a CT scan as inputs. METHODS: Patient scans and data were retrospectively selected from our institutional records for patients treated for malignant neoplasm of the rectum. We trained, validated, and tested deep learning auto-segmentation models using nnU-Net architecture for clinical target volume (CTV), bowel bag, large bowel, small bowel, total bowel, femurs, bladder, bone marrow, and female and male genitalia. For the CTV, we identified 174 patients with clinically drawn CTVs. We used data for 18 patients for all structures other than the CTV. The structures were contoured under the guidance of and reviewed by a gastrointestinal (GI) radiation oncologist. The predicted results for CTV in 35 patients and organs at risk (OAR) in six patients were scored by the GI radiation oncologist using a five-point Likert scale. For auto-planning, a RapidPlan knowledge-based planning solution was modeled for VMAT delivery with a prescription of 25 Gy in five fractions. The model was trained and tested on 20 and 34 patients, respectively. The resulting plans were scored by two GI radiation oncologists using a five-point Likert scale. Finally, the end-to-end pipeline was evaluated on 16 patients, and the resulting plans were scored by two GI radiation oncologists. RESULTS: In 31 of 35 patients, CTV contours were clinically acceptable without necessary modifications. The CTV achieved a Dice similarity coefficient of 0.85 (±0.05) and 95% Hausdorff distance of 15.25 (±5.59) mm. All OAR contours were clinically acceptable without edits, except for large and small bowel which were challenging to differentiate. However, contours for total, large, and small bowel were clinically acceptable. The two physicians accepted 100% and 91% of the auto-plans. For the end-to-end pipeline, the two physicians accepted 88% and 62% of the auto-plans. CONCLUSIONS: This study demonstrated that the VMAT treatment planning technique for rectal cancer can be automated to generate clinically acceptable and safe plans with minimal human interventions.


Assuntos
Radioterapia de Intensidade Modulada , Neoplasias Retais , Humanos , Masculino , Feminino , Radioterapia de Intensidade Modulada/métodos , Estudos Retrospectivos , Dosagem Radioterapêutica , Neoplasias Retais/radioterapia , Reto , Órgãos em Risco , Planejamento da Radioterapia Assistida por Computador/métodos
20.
Molecules ; 29(2)2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38276627

RESUMO

In this paper, the green synthesis of isoeugenol methyl ether (IEME) from eugenol by O-methylation and isomerization is completed using a one-step green process. In the methylation reaction, dimethyl carbonate (DMC) was used as a green chemistry reagent instead of the traditional harmful methylation reagents, in accordance with the current concept of green chemistry. The phase transfer catalyst (PTC) polyethylene glycol 800 (PEG-800) was introduced into the isomerization reaction to break the barrier of difficult contact between solid and liquid phases and drastically reduce the reaction conditions by shortening the reaction time and reducing the alkalinity of the reaction system. The catalytic systems for the one-step green synthesis of IEME were screened, and it was shown that the catalytic system "K2CO3 + PEG-800" was the most effective. The effects of reaction temperature, n(DMC):n(eugenol) ratio, n(PEG-800):n(eugenol) ratio, and n(K2CO3):n(eugenol) ratio on eugenol conversion, IEME yield, and IEME selectivity were investigated. The results showed that the best reaction was achieved at a reaction temperature of 140 °C, a reaction time of 3 h, a DMC drip rate of 0.09 mL/min, and n(eugenol):n(DMC):n(K2CO3):n(PEG-800) = 1:3:0.09:0.08. As a result of the conversion of 93.1% of eugenol to IEME, a yield of 86.1% IEME as well as 91.6% IEME selectivity were obtained.

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