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1.
Opt Express ; 32(12): 21855-21865, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38859529

RESUMO

A gas detection method based on CH3NH3PbI3 (MAPbI3) and poly (3,4-ethylenedioxythiophene): poly (4-styrene sulfonate) (PEDOT:PSS) composite photodetectors (PDs) is proposed. The operation of the PD primarily relies on the photoelectric effect within the visible light band. Our study involves constructing a gas detection system based on tunable diode laser spectroscopy (TDLAS) and MAPbI3/PEDOT:PSS PD, and O2 was selected as the target analyte. The system has achieved a minimum detection limit (MDL) of 0.12% and a normalized noise equivalent absorption coefficient (NNEA) of 8.83 × 10-11 cm-1⋅W⋅Hz-1/2. Furthermore, the Allan deviation analysis results indicate that the system can obtain sensitivity levels as low as 0.058% over an averaging time of 328 seconds. This marks the first use of MAPbI3/PEDOT:PSS PD in gas detection based on TDLAS. Despite the detector's performance leaves much to be desired, this innovation offers a new approach to developing spectral based gas detection system.

2.
J Neurosurg Spine ; : 1-9, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38875722

RESUMO

OBJECTIVE: Variation exists in approaches to delivery of spine stereotactic radiosurgery (SSRS). Here, the authors describe outcomes following single-fraction SSRS performed using a simultaneous integrated boost for the treatment of prostate cancer spine metastases. METHODS: Health records of patients with prostate cancer spine metastases treated with single-fraction SSRS at the authors' institution were reviewed. Treatment was uniform, with 16 Gy to the clinical tumor volume and 18 Gy to the gross tumor volume. The primary endpoint was local recurrence, with secondary endpoints including vertebral fracture and overall survival. Univariate and multivariate competing risk regression models made using the Fine and Gray method were used to identify factors predictive of local recurrence, considering death to be a competing event for local recurrence. RESULTS: A total of 87 targets involving 108 vertebrae in 68 patients were included, with a median follow-up of 22.5 months per treated target. The 1-, 2-, and 4-year cumulative incidence rates of local failure for all targets were 4.6%, 8.4%, and 19%, respectively. The presence of epidural disease (subdistribution hazard ratio [sHR] 5.43, p = 0.04) and SSRS as reirradiation (sHR 16.5, p = 0.02) emerged as significant predictors of local failure in a multivariate model. Hormone sensitivity did not predict local control. Vertebral fracture incidence rates leading to symptoms or requiring intervention at 1, 2, and 4 years were 1.1%, 3.7%, and 8.4%, respectively. In an exploratory analysis of patterns of failure, 3 (25%) failures occurred in the epidural space and only 1 (8%) occurred clearly in the clinical tumor volume. There were several lesions for which the precise location of failure with regard to target volumes was unclear. CONCLUSIONS: High rates of local control were observed, particularly for radiotherapy-naïve lesions without epidural disease. Hormone sensitivity was not predictive of local control in this cohort and fracture risk was low. Further research is needed to better predict which patients are at high risk of recurrence and who might benefit from treatment escalation.

3.
Insect Sci ; 2024 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-38880966

RESUMO

The tetraspanin gene family encodes cell-surface proteins that span the membrane 4 times and play critical roles in a wide range of biological processes across numerous organisms. Recent findings highlight the involvement of a tetraspanin of the lepidopteran pest Helicoverpa armigera in resistance to Bacillus thuringiensis Cry insecticidal proteins, which are extensively used in transgenic crops. Thus, a better understanding of lepidopteran tetraspanins is urgently needed. In the current study, genome scanning in 10 lepidopteran species identified a total of 283 sequences encoding potential tetraspanins. Based on conserved cysteine patterns in the large extracellular loop and their phylogenetic relationships, these tetraspanins were classified into 8 subfamilies (TspA to TspH). Six ancestral introns were identified within lepidopteran tetraspanin genes. Tetraspanins in TspA, TspB, TspC, and TspD subfamilies exhibit highly similar gene organization, while tetraspanins in the remaining 4 subfamilies exhibited variation in intron loss and/or gain during evolution. Analysis of chromosomal distribution revealed a lepidopteran-specific cluster of 10 to 11 tetraspanins, likely formed by tandem duplication events. Selective pressure analysis indicated negative selection across all orthologous groups, with ω values ranging between 0.004 and 0.362. However, positive selection was identified at 18 sites within TspB5, TspC5, TspE3, and TspF10. Furthermore, spatiotemporal expression analysis of H. armigera tetraspanins demonstrated variable expression levels across different developmental stages and tissues, suggesting diverse functions of tetraspanin members in this globally important insect pest. Our findings establish a solid foundation for subsequent functional investigations of tetraspanins in lepidopteran species.

4.
Int J Surg ; 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38874467

RESUMO

BACKGROUND: The emergence of robotic surgical systems compensated for the technological shortcomings of laparoscopic approaches. However, whether robotic gastrectomy (RG) has better perioperative outcomes and survival than laparoscopic gastrectomy (LG) for gastric cancer is still unclear but increasingly drawing attention. MATERIALS AND METHODS: In this systematic review and meta-analysis, we searched the PubMed, EMBASE, Web of Science, and Cochrane Library as of January 20, 2024 and referenced list of eligible articles for all published studies comparing RG and LG for patients with gastric cancer, Data on study characteristics, individual characteristics, and outcome parameters were extracted. The quality of studies was assessed using the Revised Cochrane risk-of-bias 2 tool and the risk of bias in non-randomized studies of interventions tool. The main outcome measures were overall survival (OS) and disease-free survival (DFS). RESULTS: We identified 3641 articles, of which 72 studies (30081 patients) were included in the meta-analysis. Compared with LG, RG was associated with higher OS [hazard ratio (HR)=0.89, 95% CI=0.83 to 0.96), lower rate of overall postoperative complications [odds ratio (OR)=0.77, 95% CI=0.71 to 0.84], longer operating time [mean difference (MD)=35.53, 95% CI=29.23 to 41.83], less estimated blood loss (MD=-37.45, 95% CI=-46.24 to -28.67), a higher number of retrieved lymph nodes (MD=1.88, 95% CI=0.77 to 3.00), faster postoperative recovery, and lower rate of conversion (OR=0.44, 95% CI=0.36 to 0.55). Mortality and DFS were not significantly different between the two groups. The subgroup of meta-analysis results also showed the advantages of robotic surgery over laparoscopic surgery in intracorporeal reconstruction, total gastrectomy, Ⅰ/Ⅱ stage, and BMI≥25, especially for patients with stage Ⅰ/Ⅱ, there is better overall survival and disease-free survival. CONCLUSION: Our findings point to robotic surgery having great benefits compared with laparoscopic surgery in gastric cancer. Our study may help inform decision-making in applying robotic surgical systems to clinical treatment.

5.
Nat Commun ; 15(1): 3728, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38697991

RESUMO

With improvements in survival for patients with metastatic cancer, long-term local control of brain metastases has become an increasingly important clinical priority. While consensus guidelines recommend surgery followed by stereotactic radiosurgery (SRS) for lesions >3 cm, smaller lesions (≤3 cm) treated with SRS alone elicit variable responses. To determine factors influencing this variable response to SRS, we analyzed outcomes of brain metastases ≤3 cm diameter in patients with no prior systemic therapy treated with frame-based single-fraction SRS. Following SRS, 259 out of 1733 (15%) treated lesions demonstrated MRI findings concerning for local treatment failure (LTF), of which 202 /1733 (12%) demonstrated LTF and 54/1733 (3%) had an adverse radiation effect. Multivariate analysis demonstrated tumor size (>1.5 cm) and melanoma histology were associated with higher LTF rates. Our results demonstrate that brain metastases ≤3 cm are not uniformly responsive to SRS and suggest that prospective studies to evaluate the effect of SRS alone or in combination with surgery on brain metastases ≤3 cm matched by tumor size and histology are warranted. These studies will help establish multi-disciplinary treatment guidelines that improve local control while minimizing radiation necrosis during treatment of brain metastasis ≤3 cm.


Assuntos
Neoplasias Encefálicas , Imageamento por Ressonância Magnética , Radiocirurgia , Radiocirurgia/métodos , Humanos , Neoplasias Encefálicas/secundário , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/cirurgia , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Melanoma/patologia , Adulto , Resultado do Tratamento , Carga Tumoral , Idoso de 80 Anos ou mais , Falha de Tratamento , Estudos Retrospectivos
6.
Bioact Mater ; 37: 439-458, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38698918

RESUMO

Facile and rapid 3D fabrication of strong, bioactive materials can address challenges that impede repair of large-to-massive rotator cuff tears including personalized grafts, limited mechanical support, and inadequate tissue regeneration. Herein, we developed a facile and rapid methodology that generates visible light-crosslinkable polythiourethane (PHT) pre-polymer resin (∼30 min at room temperature), yielding 3D-printable scaffolds with tendon-like mechanical attributes capable of delivering tenogenic bioactive factors. Ex vivo characterization confirmed successful fabrication, robust human supraspinatus tendon (SST)-like tensile properties (strength: 23 MPa, modulus: 459 MPa, at least 10,000 physiological loading cycles without failure), excellent suture retention (8.62-fold lower than acellular dermal matrix (ADM)-based clinical graft), slow degradation, and controlled release of fibroblast growth factor-2 (FGF-2) and transforming growth factor-ß3 (TGF-ß3). In vitro studies showed cytocompatibility and growth factor-mediated tenogenic-like differentiation of mesenchymal stem cells. In vivo studies demonstrated biocompatibility (3-week mouse subcutaneous implantation) and ability of growth factor-containing scaffolds to notably regenerate at least 1-cm of tendon with native-like biomechanical attributes as uninjured shoulder (8-week, large-to-massive 1-cm gap rabbit rotator cuff injury). This study demonstrates use of a 3D-printable, strong, and bioactive material to provide mechanical support and pro-regenerative cues for challenging injuries such as large-to-massive rotator cuff tears.

7.
Neurooncol Pract ; 11(3): 266-274, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38737610

RESUMO

Background: Glioblastoma (GBM) poses therapeutic challenges due to its aggressive nature, particularly for patients with poor functional status and/or advanced disease. Hypofractionated radiotherapy (RT) regimens have demonstrated comparable disease outcomes for this population while allowing treatment to be completed more quickly. Here, we report our institutional outcomes of patients treated with 2 hypofractionated RT regimens: 40 Gy/15fx (3w-RT) and 50 Gy/20fx (4w-RT). Methods: A single-institution retrospective analysis was conducted of 127 GBM patients who underwent 3w-RT or 4w-RT. Patient characteristics, treatment regimens, and outcomes were analyzed. Univariate and multivariable Cox regression models were used to estimate progression-free survival (PFS) and overall survival (OS). The impact of chemotherapy and RT schedule was explored through subgroup analyses. Results: Median OS for the entire cohort was 7.7 months. There were no significant differences in PFS or OS between 3w-RT and 4w-RT groups overall. Receipt and timing of temozolomide (TMZ) emerged as the variable most strongly associated with survival, with patients receiving adjuvant-only or concurrent and adjuvant TMZ having significantly improved PFS and OS (P < .001). In a subgroup analysis of patients that did not receive TMZ, patients in the 4w-RT group demonstrated a trend toward improved OS as compared to the 3w-RT group (P = .12). Conclusions: This study demonstrates comparable survival outcomes between 3w-RT and 4w-RT regimens in GBM patients. Receipt and timing of TMZ were strongly associated with survival outcomes. The potential benefit of dose-escalated hypofractionation for patients not receiving chemotherapy warrants further investigation and emphasizes the importance of personalized treatment approaches.

8.
PNAS Nexus ; 3(5): pgae172, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38745565

RESUMO

Hydrogen is gaining tremendous traction in China as the fuel of the future to support the country's carbon neutrality ambition. Despite that hydrogen as fuel largely hinges on the supply of platinum (Pt), the dynamic interlinkage between Pt supply challenges, hydrogen development pathways, and climate targets in China has yet to be deeply analyzed. Here, we adopt an integrated assessment model to address this important concern and corresponding strategies for China. The results indicate that the booming hydrogen development would drive China's cumulative demand for Pt metal to reach 4,200-5,000 tons. Much of this demand, met through a limited supply pattern, is vulnerable to price volatility and heightened geopolitical risks, which can be mitigated through circular economy strategies. Consequently, a coordinated approach to leverage both global sustainable Pt sourcing and a robust domestic Pt circular economy is imperative for ensuring cost-effective hydrogen production, aligned with a climate-safe future.

9.
Integr Med Res ; 13(2): 101039, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38746044

RESUMO

Background: Chronic fatigue is a predominant symptom of post COVID-19 condition, or long COVID. We aimed to evaluate the efficacy and safety of Traditional, Complementary and Integrative Medicine (TCIM) for fatigue post COVID-19 infection. Methods: Ten English and Chinese language databases and grey literature were searched up to 12 April 2023 for randomized controlled trials (RCTs). Cochrane "Risk of bias" (RoB) tool was applied. Evidence certainty was assessed using Grading of Recommendations Assessment, Development, and Evaluation (GRADE). Effect estimates were presented as risk ratio (RR) or mean difference (MD) with 95% confidence interval (CI). Results: Thirteen RCTs with 1632 participants were included. One RCT showed that Bufei Huoxue herbal capsules reduced fatigue (n=129, MD -14.90, 95%CI -24.53 to -5.27), one RCT reported that Ludangshen herbal liquid lowered fatigue (n=184, MD -1.90, 95%CI -2.38 to -1.42), and the other one RCT shown that fatigue disappearance rate was higher with Ludangshen herbal liquid (n=184, RR 4.19, 95%CI 2.06 to 8.53). Compared to traditional Chinese medicine rehabilitation (TCM-rahab) alone, one RCT showed that fatigue symptoms were lower following Qingjin Yiqi granules plus TCM-rehab (n=388, MD -0.48, 95%CI -0.50 to -0.46). Due to concerns with RoB and/or imprecision, the certainty in this evidence was low to very low. No serious adverse events was reported. Conclusions: Limited evidence suggests that various TCIM interventions might reduce post COVID-19 fatigue. Larger, high quality RCTs of longer duration are required to confirm these preliminary findings. Study Registration: The protocol of this review has been registered at PROSPERO: CRD42022384136.

10.
Adv Clin Exp Med ; 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38819938

RESUMO

BACKGROUND: Liqi Tongbian is a traditional Chinese medicine (TCM) preparation that contains herbs that may treat slow transit constipation (STC). Atractylodes macrocephala, Astragalus membranaceus, Fructus aurantii, radish seed, uncooked Polygonum multiflorum, and Agastache rugosa were included in the formula for their unique qualities. The control of water transfer in the colon is greatly influenced by aquaporin 3 (AQP3). OBJECTIVES: Based on this, the Liqi Tongbian mixture was used to detect the concentrations of aquaporins (AQPs), 5-HT and nitrix oxide synthase 1 (NOS1) in STC rats, and explore its effect, in order to provide a theoretical basis for the remedy of STC with TCM. MATERIAL AND METHODS: Zhejiang University of Traditional Chinese Medicine provided 32 three-week-old Sprague Dawley rats of SPF-grade. The pairs licensed under SYXK (Zhejiang) 2021-0012 were kept at 20-25°C and humidity of 50-65%. The compound diphenoxylate caused constipation in the control, model, Liqi laxative (LQTB), and mosapride groups. The Liqi laxative rats were administered a mixture of traditional Chinese herbs after modeling, while mosapride was given to the other group. The levels of 5-HT, NOS1 and AQPs were tested in the feces and intestinal tissues. RESULTS: Comparing the condition of rat feces, it was found that the model group had significantly lower overall bulk, score and particles within 24 h compared to the control group. In comparison to mosapride, LQTB performed better. The model group had higher levels of 5-HT and NOS1 in intestinal tissue, while the LQTB and mosapride groups had decreased levels of these AQPs. LQTB had lower levels of AQP1, AQP3 and AQP4 than mosapride, while the model group had higher levels of these AQPs. CONCLUSIONS: Liqi Tongbian mixture works better than mosapride in improving constipation symptoms in rats with STC, and its mechanism is related to regulating the level of intestinal AQPs and neurotransmitters.

11.
J Agric Food Chem ; 72(19): 11230-11240, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38709903

RESUMO

Dipeptidyl peptidase-IV (DPP-IV) inhibiting peptides have attracted increased attention because of their possible beneficial effects on glycemic homeostasis. However, the structural basis underpinning their activities has not been well understood. This study combined computational and in vitro investigations to explore the structural basis of DPP-IV inhibitory peptides. We first superimposed the Xaa-Pro-type peptide-like structures from several crystal structures of DPP-IV ligand-protein complexes to analyze the recognition interactions of DPP-IV to peptides. Thereafter, a small set of Xaa-Pro-type peptides was designed to explore the effect of key interactions on inhibitory activity. The intramolecular interaction of Xaa-Pro-type peptides at the first and third positions from the N-terminus was pivotal to their inhibitory activities. Residue interactions between DPP-IV and residues of the peptides at the fourth and fifth positions of the N-terminus contributed significantly to the inhibitory effect of Xaa-Pro-type tetrapeptides and pentapeptides. Based on the interaction descriptors, quantitative structure-activity relationship (QSAR) studies with the DPP-IV inhibitory peptides resulted in valid models with high R2 values (0.90 for tripeptides; 0.91 for tetrapeptides and pentapeptides) and Q2 values (0.33 for tripeptides; 0.68 for tetrapeptides and pentapeptides). Taken together, the structural information on DPP-IV and peptides in this study facilitated the development of novel DPP-IV inhibitory peptides.


Assuntos
Dipeptidil Peptidase 4 , Inibidores da Dipeptidil Peptidase IV , Peptídeos , Relação Quantitativa Estrutura-Atividade , Inibidores da Dipeptidil Peptidase IV/química , Dipeptidil Peptidase 4/química , Dipeptidil Peptidase 4/metabolismo , Peptídeos/química , Peptídeos/farmacologia , Humanos , Sequência de Aminoácidos
12.
Magn Reson Med ; 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38730562

RESUMO

PURPOSE: T1 mapping is a widely used quantitative MRI technique, but its tissue-specific values remain inconsistent across protocols, sites, and vendors. The ISMRM Reproducible Research and Quantitative MR study groups jointly launched a challenge to assess the reproducibility of a well-established inversion-recovery T1 mapping technique, using acquisition details from a seminal T1 mapping paper on a standardized phantom and in human brains. METHODS: The challenge used the acquisition protocol from Barral et al. (2010). Researchers collected T1 mapping data on the ISMRM/NIST phantom and/or in human brains. Data submission, pipeline development, and analysis were conducted using open-source platforms. Intersubmission and intrasubmission comparisons were performed. RESULTS: Eighteen submissions (39 phantom and 56 human datasets) on scanners by three MRI vendors were collected at 3 T (except one, at 0.35 T). The mean coefficient of variation was 6.1% for intersubmission phantom measurements, and 2.9% for intrasubmission measurements. For humans, the intersubmission/intrasubmission coefficient of variation was 5.9/3.2% in the genu and 16/6.9% in the cortex. An interactive dashboard for data visualization was also developed: https://rrsg2020.dashboards.neurolibre.org. CONCLUSION: The T1 intersubmission variability was twice as high as the intrasubmission variability in both phantoms and human brains, indicating that the acquisition details in the original paper were insufficient to reproduce a quantitative MRI protocol. This study reports the inherent uncertainty in T1 measures across independent research groups, bringing us one step closer to a practical clinical baseline of T1 variations in vivo.

13.
Plant Commun ; : 100926, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38725246

RESUMO

CRISPR-mediated base editors have been widely used to correct defective alleles and create novel alleles by artificial evolution for the rapid genetic improvement of crops. The editing capabilities of base editors strictly rely on the performance of various nucleotide modification enzymes. Compared with the well-developed adenine base editors (ABEs), cytosine base editors (CBEs) and dual base editors suffer from unstable editing efficiency and patterns at different genomic loci in rice, significantly limiting their application. Here, we comprehensively examined the base editing activities of multiple evolved TadA8e variants in rice. We found that both TadA-CDd and TadA-E27R/N46L achieved more robust C-to-T editing than previously reported hyperactive hAID∗Δ, and TadA-CDd outperformed TadA-E27R/N46L. A C-to-G base editor (CGBE) engineered with TadA-CDd and OsUNG performed highly efficient C-to-G editing in rice compared with that of TadA-N46P. In addition, a dual base editor constructed with a single protein, TadDE, enabled simultaneous, highly efficient C-to-T and A-to-G editing in rice. Collectively, our results demonstrate that TadA8e derivatives improve both CBEs and dual base editors in rice, providing a powerful way to induce diverse nucleotide substitutions for plant genome editing.

14.
Biochim Biophys Acta Mol Cell Res ; 1871(7): 119751, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38776988

RESUMO

Akkermansia muciniphila (A. muciniphila), a probiotic, has been linked to macrophage phenotypic polarization in different diseases. However, the role and mechanisms of A. muciniphila in regulating macrophage during ulcerative colitis (UC) are not clear. This research aimed to examine the impact of A. muciniphila on dextran sulfate sodium (DSS)-induced acute colitis and elucidate the underlying mechanism related to macrophage phenotypic polarization. A. muciniphila inhibited weight loss, increased disease activity index, and ameliorated inflammatory injury in colonic tissues in mice induced with DSS. Furthermore, A. muciniphila reduced macrophage M1 polarization and ameliorated epithelial barrier damage in colonic tissues of DSS-induced mice through inhibition of histone deacetylase 5 (HDAC5). In contrast, the effect of A. muciniphila was compromised by HDAC5 overexpression. HDAC5 deacetylated H3K9ac modification of the disabled homolog 2 (DAB2) promoter, which led to repressed DAB2 expression. DAB2 overexpression blocked HDAC5-induced pro-inflammatory polarization of macrophages, whereas knockdown of DAB2 resulted in the loss of effects of A. muciniphila against colonic injury in DSS-induced mice. Taken together, A. muciniphila-induced loss of HDAC5 hampered the deacetylation of DAB2 and enhanced the expression of DAB2. Our findings propose that A. muciniphila may be a possible probiotic agent for alleviating DSS-induced acute colitis.

15.
J Environ Manage ; 359: 121006, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38692028

RESUMO

Education expenditure is essential in mitigating air pollution, but the relationship between education expenditure and air pollution lacks in-depth discussion. Utilizing data at the county level in China during 2007-2021, this study estimates the effect of education expenditure from local governments on air pollution. Our findings demonstrate that education expenditure significantly and negatively affects air pollution, which remains robust after addressing endogeneity. The mechanism analysis presents that education expenditure reduces air pollution through the composition, technique, and income effects. The heterogeneity analysis indicates that the impact of education expenditure exhibits marked regional heterogeneity. Specifically, the role of education expenditure is significant in strong regulation, key, eastern, and central regions. By considering interaction terms, we identify the moderating effects of human capital, economic development, infrastructure construction, and public service for education expenditure. The cost-benefit analysis emphasizes that education expenditure improves social welfare. Our findings can inspire local governments to place more emphasis on air quality and public education expenditure.


Assuntos
Poluição do Ar , China , Humanos , Educação , Análise Custo-Benefício
16.
Phys Rev Lett ; 132(18): 183803, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38759188

RESUMO

Time crystal is a class of nonequilibrium phases with broken time-translational symmetry. Here, we demonstrate the time crystal in a single-mode nonlinear cavity. The time crystal originates from the self-oscillation induced by a linear gain and is stabilized by a nonlinear damping. We show in the time crystal phase there are sharp dissipative gap closing and pure imaginary eigenvalues of the Liouvillian spectrum in the thermodynamic limit. Dynamically, we observe a metastable regime with the emergence of quantum oscillation, followed by a dissipative evolution with a timescale much longer than the oscillating period. Moreover, we show there is a dissipative phase transition at the Hopf bifurcation, which can be characterized by the photon number fluctuation in the steady state. These results pave a new promising way for further experiments and deepen our understanding of time crystals.

17.
Nat Genet ; 56(6): 1257-1269, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38802564

RESUMO

Na+ exclusion from above-ground tissues via the Na+-selective transporter HKT1;5 is a major salt-tolerance mechanism in crops. Using the expression genome-wide association study and yeast-one-hybrid screening, we identified TaSPL6-D, a transcriptional suppressor of TaHKT1;5-D in bread wheat. SPL6 also targeted HKT1;5 in rice and Brachypodium. A 47-bp insertion in the first exon of TaSPL6-D resulted in a truncated peptide, TaSPL6-DIn, disrupting TaHKT1;5-D repression exhibited by TaSPL6-DDel. Overexpressing TaSPL6-DDel, but not TaSPL6-DIn, led to inhibited TaHKT1;5-D expression and increased salt sensitivity. Knockout of TaSPL6-DDel in two wheat genotypes enhanced salinity tolerance, which was attenuated by a further TaHKT1;5-D knockdown. Spike development was preserved in Taspl6-dd mutants but not in Taspl6-aabbdd mutants. TaSPL6-DIn was mainly present in landraces, and molecular-assisted introduction of TaSPL6-DIn from a landrace into a leading wheat cultivar successfully improved yield on saline soils. The SPL6-HKT1;5 module offers a target for the molecular breeding of salt-tolerant crops.


Assuntos
Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Tolerância ao Sal , Triticum , Triticum/genética , Proteínas de Plantas/genética , Tolerância ao Sal/genética , Proteínas de Transporte de Cátions/genética , Estudo de Associação Genômica Ampla , Oryza/genética , Simportadores/genética , Simportadores/metabolismo , Pão , Plantas Geneticamente Modificadas , Brachypodium/genética , Salinidade
18.
Bioorg Chem ; 148: 107461, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38788363

RESUMO

Stachybatranones A-F (1a/1b and 2-6) and three known analogues, namely methylatranones A and B (7 and 8) and atranone B (9), were isolated and identified from a toxigenic fungus Stachybotrys chartarum. Their structures and absolute configurations were elucidated via the extensive spectroscopic data, comparison of the experimental electronic circular dichroism (ECD) data, and single-crystal X-ray diffraction analyses. Structurally, compounds 2-6 belonged to a rare class of C-alkylated dolabellanes, featuring a unique five-membered hemiketal ring and a γ-butyrolactone moiety both fused to an 11-membered carbocyclic system, while compound 1 (1a/1b) represented the first example of a 5-11-6-fused atranone possessing a 2,3-butanediol moiety. The cardiomyocyte protective activity assay revealed that compounds 1-9 ameliorated cold ischemic injury at 24 h post cold ischemia (CI), with compounds 1 and 4 acting in a dose-dependent manner. Moreover, compound 1 prevented cold ischemia induced dephosphorylation of PI3K and AKT acting in a dose-dependent manner. In this study, a new class of natural products were found to protect cardiomyocytes against cold ischemic injury, providing a potential option for the development of novel cardioprotectants in heart transplant medicine.


Assuntos
Miócitos Cardíacos , Stachybotrys , Stachybotrys/química , Animais , Miócitos Cardíacos/efeitos dos fármacos , Estrutura Molecular , Relação Estrutura-Atividade , Relação Dose-Resposta a Droga , Ratos , Descoberta de Drogas , Produtos Biológicos/farmacologia , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Substâncias Protetoras/farmacologia , Substâncias Protetoras/química , Substâncias Protetoras/isolamento & purificação
19.
Chem Biol Interact ; 396: 111043, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38735450

RESUMO

Microplastics have emerged as environmental hazards in recent years. This study was intended to prove the toxic effects of microplastics on the male reproductive system and further elucidate its mechanism. C57bl/6 mice were exposed to ultrapure water or different doses (0.25, 0.5 and 1 mg/d) of 5 µm polystyrene microplastics (PS-MPs) for 4 weeks, and the GC-1 mouse spermatogonium was treated with different concentrations of PS-MPs. The results showed that sperm count and motility were decreased, and sperm deformity rate was increased after exposure to PS-MPs. The morphology of testes in PS-MPs groups exhibited pathological changes, such as abnormal development of spermatogenic tubules, and inhibited spermatogonium function. Furthermore, the fluorescence intensity of TUNEL staining and the BAX/BCL2 ratio were increased. Exposure to PS-MPs resulted in impaired mitochondrial morphology of spermatogonium, decreased activity of GSH-px and SOD, and increased the MDA level. In vitro, after treatment with PS-MPs, the cell apoptosis rate of spermatogonium was significantly increased, mitochondrial membrane potential was decreased, mitochondrial morphology was damaged, and exposure to PS-MPs increased mitochondrial reactive oxygen species, inducing an oxidative stress state in spermatogonia. In summary, PS-MPs induced a decrease in sperm quality by activating spermatogonium mitochondrial oxidative stress and apoptosis, offering novel insights into mitigating the reproductive toxicity of microplastics.


Assuntos
Apoptose , Potencial da Membrana Mitocondrial , Camundongos Endogâmicos C57BL , Microplásticos , Mitocôndrias , Estresse Oxidativo , Poliestirenos , Motilidade dos Espermatozoides , Espermatogônias , Testículo , Animais , Masculino , Apoptose/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Microplásticos/toxicidade , Poliestirenos/toxicidade , Poliestirenos/química , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Testículo/efeitos dos fármacos , Testículo/patologia , Testículo/metabolismo , Espermatogônias/efeitos dos fármacos , Espermatogônias/metabolismo , Espermatogônias/patologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Motilidade dos Espermatozoides/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Espermatozoides/efeitos dos fármacos , Espermatozoides/patologia , Contagem de Espermatozoides , Superóxido Dismutase/metabolismo
20.
Quant Imaging Med Surg ; 14(4): 2828-2839, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38617175

RESUMO

Background: Improved coronary physiological function after percutaneous coronary intervention (PCI) has been shown to improve prognosis in stable ischaemic heart disease, but has not yet been explored in ST-segment elevated myocardial infarction (STEMI). The study sought to determine whether an improvement in the quantitative flow ratio (QFR) could improve the prognosis of STEMI patients undergoing primary PCI. Methods: Patients diagnosed with STEMI who were receiving primary PCI were recruited for the study. Those with thrombolysis in myocardial infarction (TIMI) flow <2 after wiring were excluded. The ΔQFR was calculated using the following formula: ΔQFR = post-PCI QFR - pre-stent QFR. The primary endpoint was the composite event, including recurrent myocardial infarction (MI) and acute heart failure (AHF). Results: In total, 515 STEMI patients with a median follow-up of 364 days were enrolled in the study. Based on the cut-off value from the receiver operator characteristic (ROC) curve, the patients were divided into the following two groups: the lower ΔQFR group (≤0.25, N=332); and the normal ΔQFR group (>0.25, N=183). Patients with a lower ΔQFR had a relatively higher rate of MI/AHF (10.5% vs. 4.4%, P=0.019) and AHF (7.2% vs. 2.7%, P=0.044). A lower ΔQFR was significantly associated with a higher incidence of MI/AHF [hazard ratio (HR) =2.962, 95% confidence interval (CI): 1.358-6.459, P=0.006, respectively] after adjusting for potential confounders. Pre-stent angiographic microvascular resistance [odds ratio (OR) =1.027, 95% CI: 1.022-1.033, P<0.001] and the stent-to-vessel diameter ratio <1.13 (OR =1.766, 95% CI: 1.027-3.071, P=0.04) were independent predictors of a lower ΔQFR. Conclusions: An insufficient improvement in the QFR contributes to worsening outcomes and might be a useful tool for risk stratification in STEMI.

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