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1.
Cell ; 187(16): 4272-4288.e20, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39013469

RESUMO

Vesicle trafficking is a fundamental process that allows for the sorting and transport of specific proteins (i.e., "cargoes") to different compartments of eukaryotic cells. Cargo recognition primarily occurs through coats and the associated proteins at the donor membrane. However, it remains unclear whether cargoes can also be selected at other stages of vesicle trafficking to further enhance the fidelity of the process. The WDR11-FAM91A1 complex functions downstream of the clathrin-associated AP-1 complex to facilitate protein transport from endosomes to the TGN. Here, we report the cryo-EM structure of human WDR11-FAM91A1 complex. WDR11 directly and specifically recognizes a subset of acidic clusters, which we term super acidic clusters (SACs). WDR11 complex assembly and its binding to SAC-containing proteins are indispensable for the trafficking of SAC-containing proteins and proper neuronal development in zebrafish. Our studies thus uncover that cargo proteins could be recognized in a sequence-specific manner downstream of a protein coat.


Assuntos
Microscopia Crioeletrônica , Transporte Proteico , Peixe-Zebra , Humanos , Animais , Endossomos/metabolismo , Células HEK293 , Células HeLa , Proteínas de Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/química , Ligação Proteica
2.
Plant J ; 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39145531

RESUMO

Grain appearance and nutritional quality are critical traits for rice marketing. However, how to simultaneously improve grain appearance (slender grain and low chalkiness) and nutritional quality (improved protein and amino acid contents) in rice remains a major challenge. Here, we show that knocking out rice isopropylmalate synthase genes OsIPMS1 and OsIPMS2 can improve both grain appearance and nutritional quality. We find that OsIPMS1 directly interacts with OsIPMS2 to form heterodimers. Meanwhile, we observe that OsIPMS1 and OsIPMS2 influence the expression of genes previously reported to be involved in the determination of grain size and nutritional quality in the developing panicles and grains. Furthermore, we show that Osipms1/2 double mutants exhibit significantly improved grain appearance and nutritional quality in polished rice in both the japonica (Wuyungeng 23) and indica (Huanghuazhan) varieties. Our findings indicate that OsIPMS is a useful target gene for breeding of rice varieties appealing for marketing and with health-benefiting properties.

3.
Chem Soc Rev ; 53(1): 502-544, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38099340

RESUMO

Covalent organic frameworks (COFs) represent an important class of crystalline porous materials with designable structures and functions. The interconnected organic monomers, featuring pre-designed symmetries and connectivities, dictate the structures of COFs, endowing them with high thermal and chemical stability, large surface area, and tunable micropores. Furthermore, by utilizing pre-functionalization or post-synthetic functionalization strategies, COFs can acquire multifunctionalities, leading to their versatile applications in gas separation/storage, catalysis, and optoelectronic devices. Our review provides a comprehensive account of the latest advancements in the principles, methods, and techniques for structural design and determination of COFs. These cutting-edge approaches enable the rational design and precise elucidation of COF structures, addressing fundamental physicochemical challenges associated with host-guest interactions, topological transformations, network interpenetration, and defect-mediated catalysis.

4.
J Lipid Res ; : 100623, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39154732

RESUMO

Natriuretic peptide receptor-C (NPR-C) is highly expressed in adipose tissues, and regulates obesity related diseases, however the detailed mechanism remains unknown. In this research, we aimed to explore the potential role of NPR-C in cold exposure and high-fat/high-sugar (HF/HS) diet induced metabolic changes, especially in regulating white adipose tissue (WAT) mitochondrial function. Our findings showed that NPR-C expression, especially in epididymal WAT (eWAT), was reduced after cold exposure. Global Npr3 (gene encoding NPR-C protein) deficiency led to reduced body weight, increased WAT browning, thermogenesis, and enhanced expression of genes related to mitochondrial biogenesis. RNA-sequencing of eWAT showed that Npr3 deficiency enhanced expression of mitochondrial respiratory chain complex genes and promoted mitochondrial oxidative phosphorylation in response to cold exposure. In addition, Npr3 KO mice were able to resist obesity induced by HF/HS diet. Npr3 knockdown in stromal vascular fraction (SVF)-induced white adipocytes promoted the expression of proliferator-activated receptor gamma coactivator 1α (PGC1α), uncoupling protein 1 (UCP1) and mitochondrial respiratory chain complexes. Mechanistically, NPR-C inhibited cGMP and calcium signaling in an NPR-B-dependent manner but suppressed cAMP signaling in an NPR-B-independent manner. Moreover, Npr3 knockdown induced browning via AKT and p38 pathway activation, which were attenuated by Npr2 knockdown. Importantly, treatment with the NPR-C specific antagonist, AP-811, decreased WAT mass and increased PGC-1α, UCP1 and mitochondrial complex expression. These findings demonstrate that NPR-C deficiency enhances metabolic health by boosting energy expenditure in WAT, emphasizing the potential of NPR-C inhibition for treating obesity and related metabolic disorders.

5.
J Physiol ; 602(2): 355-372, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38165402

RESUMO

This study aimed to determine which physiological factors impact net efficiency (ηnet) in oldest-old individuals at different stages of skeletal muscle disuse. To this aim, we examined ηnet, central haemodynamics, peripheral circulation, and peripheral factors (skeletal muscle fibre type, capillarization and concentration of mitochondrial DNA [mtDNA]). Twelve young (YG; 25 ± 2 years), 12 oldest-old mobile (OM; 87 ± 3 years), and 12 oldest-old immobile (OI; 88 ± 4 years) subjects performed dynamic knee extensor (KE) and elbow flexors (EF) exercise. Pulmonary oxygen uptake, photoplethysmography, Doppler ultrasound and muscle biopsies of the vastus lateralis and biceps brachii were used to assess central and peripheral adaptations to advanced ageing and disuse. Compared to the YG (12.1 ± 2.4%), the ηnet of lower-limb muscle was higher in the OM (17.6 ± 3.5%, P < 0.001), and lower in the OI (8.9 ± 1.9%, P < 0.001). These changes in ηnet during KE were coupled with significant peripheral adaptations, revealing strong correlations between ηnet and the proportion of type I muscle fibres (r = 0.82), as well as [mtDNA] (r = 0.77). No differences in ηnet were evident in the upper-limb muscles between YG, OM and OI. In view of the differences in limb-specific activity across the lifespan, these findings suggest that ηnet is reduced by skeletal muscle inactivity and not by chronological age, per se. Likewise, this study revealed that the age-related changes in ηnet are not a consequence of central or peripheral haemodynamic adaptations, but are likely a product of peripheral changes related to skeletal muscle fibre type and mitochondrial density. KEY POINTS: Although the effects of ageing and muscle disuse deeply impact the cardiovascular and skeletal muscle function, the combination of these factors on the mechanical efficiency are still a matter of debate. By measuring both upper- and lower-limb muscle function, which experience differing levels of disuse, we examined the influence of central and peripheral haemodynamics, and skeletal muscle factors linked to mechanical efficiency. Across the ages and degree of disuse, upper-limb muscles exhibited a preserved work economy. In the legs the oldest-old without mobility limitations exhibited an augmented mechanical efficiency, which was reduced in those with an impairment in ambulation. These changes in mechanical efficiency were associated with the proportion of type I muscle fibres. Recognition that the mechanical efficiency is not simply age-dependent, but the consequence of inactivity and subsequent skeletal muscle changes, highlights the importance of maintaining physical activity across the lifespan.


Assuntos
Fibras Musculares Esqueléticas , Músculo Esquelético , Humanos , Idoso de 80 Anos ou mais , Músculo Esquelético/fisiologia , Fibras Musculares Esqueléticas/fisiologia , Envelhecimento/fisiologia , Extremidade Inferior , DNA Mitocondrial
6.
J Am Chem Soc ; 146(14): 9871-9879, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38547318

RESUMO

Carbenes, recognized as potent intermediates, enable unique chemical transformations, and organoborons are pivotal in diverse chemical applications. As a hybrid of carbene and the boryl group, α-boryl carbenes are promising intermediates for the construction of organoborons; unfortunately, such carbenes are hard to access and have low structural diversity with their asymmetric transformations largely uncharted. In this research, we utilized boryl cyclopropenes as precursors for the swift synthesis of α-boryl metal carbenes, a powerful category of intermediates for chiral organoboron synthesis. These α-boryl carbenes undergo a series of highly enantioselective transfer reactions, including B-H and Si-H insertion, cyclopropanation, and cyclopropanation/Cope rearrangement, catalyzed by a singular chiral copper complex. This approach opens paths to previously unattainable but easily transformable chiral organoborons, expanding both carbene and organoboron chemistry.

7.
Br J Cancer ; 130(4): 694-700, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38177659

RESUMO

BACKGROUND: Neoadjuvant chemo-immunotherapy combination has shown remarkable advances in the management of esophageal squamous cell carcinoma (ESCC). However, the identification of a reliable biomarker for predicting the response to this chemo-immunotherapy regimen remains elusive. While computed tomography (CT) is widely utilized for response evaluation, its inherent limitations in terms of accuracy are well recognized. Therefore, in this study, we present a novel technique to predict the response of ESCC patients before receiving chemo-immunotherapy by testing volatile organic compounds (VOCs) in exhaled breath. METHODS: This study employed a prospective-specimen-collection, retrospective-blinded-evaluation design. Patients' baseline breath samples were collected and analyzed using high-pressure photon ionization time-of-flight mass spectrometry (HPPI-TOFMS). Subsequently, patients were categorized as responders or non-responders based on the evaluation of therapeutic response using pathology (for patients who underwent surgery) or CT images (for patients who did not receive surgery). RESULTS: A total of 133 patients were included in this study, with 91 responders who achieved either a complete response (CR) or a partial response (PR), and 42 non-responders who had stable disease (SD) or progressive disease (PD). Among 83 participants who underwent both evaluations with CT and pathology, the paired t-test revealed significant differences between the two methods (p < 0.05). For the breath test prediction model using breath test data from all participants, the validation set demonstrated mean area under the curve (AUC) of 0.86 ± 0.06. For 83 patients with pathological reports, the breath test achieved mean AUC of 0.845 ± 0.123. CONCLUSIONS: Since CT has inherent weakness in hollow organ assessment and no other ideal biomarker has been found, our study provided a noninvasive, feasible, and inexpensive tool that could precisely predict ESCC patients' response to neoadjuvant chemo-immunotherapy combination using breath test based on HPPI-TOFMS.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Carcinoma de Células Escamosas do Esôfago/terapia , Neoplasias Esofágicas/terapia , Neoplasias Esofágicas/tratamento farmacológico , Estudos Retrospectivos , Estudos Prospectivos , Terapia Neoadjuvante , Testes Respiratórios/métodos , Biomarcadores
8.
Biochem Cell Biol ; 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39116458

RESUMO

Diabetic nephropathy (DN) is one of the most common complications of diabetes. Our previous study showed that CD38 knockout (CD38KO) mice had protective effects on many diseases. However, the roles and mechanisms of CD38 in DN remain unknown. Here, DN mice were generated by HFD feeding plus streptozotocin (STZ) injection in male CD38KO and CD38flox mice. Mesangial cells (SV40 MES 13 cells) were used to mimic the injury of DN with palmitic acid (PA) treatment in vitro. Our results showed that CD38 expression was significantly increased in kidney of diabetic CD38flox mice and SV40 MES 13 cells treated with PA. CD38KO mice were significantly resistant to diabetes-induced renal injury. Moreover, CD38 deficiency markedly decreased HFD/STZ-induced lipid accumulation, fibrosis and oxidative stress in kidney tissue. In contrast, overexpression of CD38 aggravated PA-induced lipid accumulation and oxidative stress. CD38 deficiency increased expression of SIRT3, while overexpression of CD38 decreased its expression. More importantly, 3-TYP, an inhibitor of SIRT3, significantly enhanced PA-induced lipid accumulation and oxidative stress in CD38 overexpressing cell lines. In conclusion, our results demonstrated that CD38 deficiency prevented DN by inhibiting lipid accumulation and oxidative stress through activation of the SIRT3 pathway.

9.
Anal Chem ; 96(24): 10046-10055, 2024 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-38845359

RESUMO

Extracellular vesicle (EV) molecular phenotyping offers enormous opportunities for cancer diagnostics. However, the majority of the associated studies adopted biomarker-based unimodal analysis to achieve cancer diagnosis, which has high false positives and low precision. Herein, we report a multimodal platform for the high-precision diagnosis of bladder cancer (BCa) through a multispectral 3D DNA machine in combination with a multimodal machine learning (ML) algorithm. The DNA machine was constructed using magnetic microparticles (MNPs) functionalized with aptamers that specifically identify the target of interest, i.e., five protein markers on bladder-cancer-derived urinary EVs (uEVs). The aptamers were hybridized with DNA-stabilized silver nanoclusters (DNA/AgNCs) and a G-quadruplex/hemin complex to form a sensing module. Such a DNA machine ensured multispectral detection of protein markers by fluorescence (FL), inductively coupled plasma mass spectrometry (ICP-MS), and UV-vis absorption (Abs). The obtained data sets then underwent uni- or multimodal ML for BCa diagnosis to compare the analytical performance. In this study, urine samples were obtained from our prospective cohort (n = 45). Our analytical results showed that the 3D DNA machine provided a detection limit of 9.2 × 103 particles mL-1 with a linear range of 4 × 104 to 5 × 107 particles mL-1 for uEVs. Moreover, the multimodal data fusion model exhibited an accuracy of 95.0%, a precision of 93.1%, and a recall rate of 93.2% on average, while those of the three types of unimodal models were no more than 91%. The elevated diagnosis precision by using the present fusion platform offers a perspective approach to diminishing the rate of misdiagnosis and overtreatment of BCa.


Assuntos
Aprendizado de Máquina , Neoplasias da Bexiga Urinária , Neoplasias da Bexiga Urinária/diagnóstico , Neoplasias da Bexiga Urinária/urina , Humanos , Biomarcadores Tumorais/urina , Biomarcadores Tumorais/análise , DNA/química , Prata/química , Aptâmeros de Nucleotídeos/química , Vesículas Extracelulares/química , Nanopartículas Metálicas/química
10.
Artigo em Inglês | MEDLINE | ID: mdl-39120468

RESUMO

Peripheral microvascular dysfunction has been documented in patients with heart failure with preserved ejection fraction (HFpEF), which may be related to elevated levels of inflammation and oxidative stress. Unfortunately, few strategies have been identified to effectively ameliorate this disease-related derangement. Thus, using a parallel, double-blind, placebo-controlled design, this study evaluated the efficacy of 30-day atorvastatin administration (10mg QD) on lower limb microvascular reactivity, functional capacity, and biomarkers of inflammation and oxidative stress in patients with HFpEF (Statin: n=8, 76±6 yr; Placebo: n=8, 68±9 yr). The passive limb movement (PLM)-induced hyperemic response and 6-Minute Walk Test (6MWT) distance were evaluated to assess ambulatory muscle microvascular function and functional capacity, respectively. Circulating biomarkers were also measured to assess the contribution of changes in inflammation and redox balance to these outcomes. The total hyperemic response to PLM, assessed as leg blood flow area under-the-curve (LBFAUC), increased following the statin intervention (pre: 60 ± 68 mL; post: 164 ± 90 mL; P < 0.01), whereas these variables were unchanged in the placebo group (P=0.99). There were no significant differences in 6MWT distance following statin or placebo intervention. Malondialdehyde (MDA), a marker of lipid peroxidation, was significantly reduced following the statin intervention (pre: 0.68 ± 0.10; post: 0.51 ± 0.11; P < 0.01), while other circulating biomarkers were unchanged. Together, these data provide new evidence for the efficacy of low-dose statin administration to improve locomotor muscle microvascular reactivity in patients with HFpEF, which may be due, in part, to a diminution in oxidative stress.

11.
Biochem Biophys Res Commun ; 700: 149535, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38308909

RESUMO

To compare the merits and drawbacks of three approaches for establishing a rabbit model of nonobstructive coronary microcirculatory disease, namely, open thoracic subtotal ligation of coronary arteries, ultrasound-guided cardiac microsphere injection, and sodium laurate injection. New Zealand rabbits were allocated to four groups: a normal group (Blank group), an Open-chest group (Open-chest), a microsphere group (Echo-M), and a sodium laurate group (Echo-SL), each comprising 10 rabbits. The rabbits were sacrificed 24 h after the procedures, and their echocardiography, stress myocardial contrast echocardiography, pathology, and surgical times were compared. The results demonstrated varying degrees of reduced cardiac function in all three experimental groups, the Open-chest group exhibiting the most significant decline. The myocardial filling in the affected areas was visually analyzed by myocardial contrast echocardiography, revealing sparse filling at rest but more after stress. Quantitative analysis of perfusion parameters (ß, A, MBF) in the affected myocardium showed reduced values, the Open-chest group having the most severe reductions. No differences were observed in stress myocardial acoustic imaging parameters between the Echo-M and Echo-SL groups. Among the pathological presentations, the Open-chest model predominantly exhibited localized ischemia, while the Echo-M model was characterized by mechanical physical embolism, and the Echo-SL model displayed in situ thrombosis as the primary pathological feature. Inflammatory responses and collagen deposition were observed in all groups, with the severity ranking of Open-chest > Echo-SL > Echo-M. The ultrasound-guided intracardiac injection method used in this experiment outperformed open-chest surgery in terms of procedural efficiency, invasiveness, and maneuverability. This study not only optimizes established cardiac injection techniques but also offers valuable evidence to support clinical investigations through a comparison of various modeling methods.


Assuntos
Doença da Artéria Coronariana , Circulação Coronária , Coelhos , Animais , Microcirculação , Circulação Coronária/fisiologia , Miocárdio/patologia
12.
J Neurosci Res ; 102(8): e25372, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39086264

RESUMO

The objective of this study was to investigate the potential mechanisms by which (+)-catechin alleviates neuropathic pain. Thirty-two male Sprague-Dawley rats were divided into four groups: the sham group, the chronic constriction injury (CCI)group, the CCI+ ibuprofen group, and the CCI+ (+)-catechin group. CCI surgery induces thermal hyperalgesia in rats and (+)-catechin ameliorated CCI-induced thermal hyperalgesia and repaired damaged sciatic nerve in rats. CCI decreased SOD levels in male rat spinal cord dorsal horn and promoted MDA production, induced oxidative stress by increasing NOX4 levels and decreasing antioxidant enzyme HO-1 levels, and also increased protein levels of TLR4, p-NF-κB, NLRP3 inflammasome components, and IL-1ß. In contrast, (+)-catechin reversed the above results. In i vitro experiments, (+)-catechin reduced the generation of reactive oxygen species (ROS) in GMI-R1 cells after LPS stimulation and attenuated the co-expression of IBA-1 and NLRP3. It also showed significant inhibition of the NF-κB and NLRP3 inflammatory pathways and activation of the Nrf2-mediated antioxidant system. Overall, these findings suggest that (+)-catechin inhibits the activation of the NLRP3 inflammasome through the triggering of the Nrf2-induced antioxidant system, the inhibition of the TLR4/NF-κB pathway, and the production of ROS to alleviate CCI-induced neuropathic pain in male rats.


Assuntos
Antioxidantes , Catequina , Inflamassomos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Neuralgia , Transdução de Sinais , Animais , Masculino , Ratos , Antioxidantes/farmacologia , Catequina/farmacologia , Hiperalgesia/metabolismo , Hiperalgesia/tratamento farmacológico , Inflamassomos/metabolismo , Inflamassomos/efeitos dos fármacos , Neuralgia/metabolismo , Neuralgia/tratamento farmacológico , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/metabolismo , Receptor 4 Toll-Like/efeitos dos fármacos
13.
Ann Surg Oncol ; 31(8): 5011-5020, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38520581

RESUMO

BACKGROUND: Noninvasively and accurately predicting subcarinal lymph node metastasis (SLNM) for patients with non-small cell lung cancer (NSCLC) remains challenging. This study was designed to develop and validate a tumor and subcarinal lymph nodes (tumor-SLNs) dual-region computed tomography (CT) radiomics model for predicting SLNM in NSCLC. METHODS: This retrospective study included NSCLC patients who underwent lung resection and SLNs dissection between January 2017 and December 2020. The radiomic features of the tumor and SLNs were extracted from preoperative CT, respectively. Ninety machine learning (ML) models were developed based on tumor region, SLNs region, and tumor-SLNs dual-region. The model performance was assessed by the area under the curve (AUC) and validated internally by fivefold cross-validation. RESULTS: In total, 202 patients were included in this study. ML models based on dual-region radiomics showed good performance for SLNM prediction, with a median AUC of 0.794 (range, 0.686-0.880), which was superior to those of models based on tumor region (median AUC, 0.746; range, 0.630-0.811) and SLNs region (median AUC, 0.700; range, 0.610-0.842). The ML model, which is developed by using the naive Bayes algorithm and dual-region features, had the highest AUC of 0.880 (range of cross-validation, 0.825-0.937) among all ML models. The optimal logistic regression model was inferior to the optimal ML model for predicting SLNM, with an AUC of 0.727. CONCLUSIONS: The CT radiomics showed the potential for accurately predicting SLNM in NSCLC patients. The ML model with dual-region radiomic features has better performance than the logistic regression or single-region models.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Metástase Linfática , Aprendizado de Máquina , Tomografia Computadorizada por Raios X , Humanos , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Carcinoma Pulmonar de Células não Pequenas/secundário , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/cirurgia , Masculino , Feminino , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos , Pessoa de Meia-Idade , Idoso , Seguimentos , Prognóstico , Adulto , Linfonodos/patologia , Linfonodos/diagnóstico por imagem , Linfonodos/cirurgia , Idoso de 80 Anos ou mais , Excisão de Linfonodo , Pneumonectomia , Radiômica
14.
Opt Express ; 32(11): 19230-19241, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38859062

RESUMO

This study proposes an efficient and accurate method for parameter extraction of quantum well distributed feedback (DFB) lasers by combining the rate equation model, finite element method, transmission matrix method, and traveling wave model (TWM). By fabricating and measuring the companion Fabry-Perot (FP) lasers, material and structural parameters common with the target DFB laser are extracted efficiently. All the intrinsic parameters of the DFB laser are accurately extracted by integrating multiple mathematical models, and the possibility of multiple solutions is avoided. From the extracted parameters, the output characteristics of the DFB laser are simulated using the TWM. The simulation results agree closely with the experimental results, proving the feasibility and accuracy of the proposed method.

15.
Opt Express ; 32(2): 1764-1775, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38297721

RESUMO

Optoelectronic integrated circuits (OEICs) have enhanced integration and communication capabilities in various applications. With the continued increase in complexity and scale, the need for an accurate and efficient simulation environment compatible with photonics and electronics becomes paramount. This paper introduces a method using the Verilog-A hardware language in the electronic design automation (EDA) platform to create equivalent circuit and compact models for photonic devices, considering their dispersion, polarization, multimode, and bidirectional transmission characteristics. These models can be co-simulated alongside electrical components in the electronic simulator, covering both the time and frequency domains simultaneously. Model parameters can be modified at any stage of the design process. Using the full link of an optoelectronic transceiver as an example, analyses from our Verilog-A model system show a mean absolute percentage error of 1.55% in the time-domain and 0.0318% in the frequency-domain when compared to the commercial co-simulation system (e.g., Virtuoso-INTERCONNECT). This underscores the accuracy and efficiency of our approach in OEICs design. By adopting this method, designers are enabled to conduct both electrical-specific and photonic-specific circuit analyses, as well as perform optoelectronic co-simulation within a unified platform seamlessly.

16.
Microb Pathog ; 192: 106723, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823465

RESUMO

The Hedgehog (Hh) signaling pathway is involved in T cell differentiation and development and plays a major regulatory part in different stages of T cell development. A previous study by us suggested that prenatal exposure to staphylococcal enterotoxin B (SEB) changed the percentages of T cell subpopulation in the offspring thymus. However, it is unclear whether prenatal SEB exposure impacts the Hh signaling pathway in thymic T cells. In the present study, pregnant rats at gestational day 16 were intravenously injected once with 15 µg SEB, and the thymi of both neonatal and adult offspring rats were aseptically acquired to scrutinize the effects of SEB on the Hh signaling pathway. It firstly found that prenatal SEB exposure clearly caused the increased expression of Shh and Dhh ligands of the Hh signaling pathway in thymus tissue of both neonatal and adult offspring rats, but significantly decreased the expression levels of membrane receptors of Ptch1 and Smo, transcription factor Gli1, as well as target genes of CyclinD1, C-myc, and N-myc in Hh signaling pathway of thymic T cells. These data suggest that prenatal SEB exposure inhibits the Hh signaling pathway in thymic T lymphocytes of the neonatal offspring, and this effect can be maintained in adult offspring via the imprinting effect.


Assuntos
Enterotoxinas , Proteínas Hedgehog , Transdução de Sinais , Linfócitos T , Timo , Animais , Proteínas Hedgehog/metabolismo , Proteínas Hedgehog/genética , Feminino , Gravidez , Ratos , Timo/metabolismo , Timo/imunologia , Linfócitos T/imunologia , Linfócitos T/metabolismo , Proteína GLI1 em Dedos de Zinco/metabolismo , Proteína GLI1 em Dedos de Zinco/genética , Receptor Patched-1/metabolismo , Receptor Patched-1/genética , Receptor Smoothened/metabolismo , Receptor Smoothened/genética , Efeitos Tardios da Exposição Pré-Natal/imunologia , Diferenciação Celular/efeitos dos fármacos , Ratos Sprague-Dawley , Masculino
17.
Rev Cardiovasc Med ; 25(3): 85, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-39076944

RESUMO

Background: For individuals with persistent stable chest pain (SCP) and a coronary artery calcium score (CACS) of 0, it might be challenging to establish the best risk assessment method for determining the individuals who will not benefit from further cardiovascular imaging testing (CIT). Thus, we investigated the CACS-weighted clinical likelihood (CACS-CL) model in SCP patients with a CACS of 0. Methods: Thus, to assess SCP, we originally enrolled 14,232 individuals for CACS and coronary computed tomography angiography (CCTA) scans between January 2016 and January 2018. Finally, patients with a CACS of 0 were included and followed up ​until January 2022. According to the established CACS-CL cutoffs of 15% and 5%, the associations between coronary artery disease (CAD) and major adverse cardiovascular events (MACEs) in risk groups were evaluated, alongside the net reclassification improvement (NRI). Results: Of the 6689 patients with a CACS of 0, the prevalence of CAD increased significantly (p < 0.0001) in patients with higher CACS-CL. However, there was no significant difference in the CAD distribution (p = 0.0637) between patients with CACS-CL < 5% and 5-15%. The association between the CACS-CL = 15%-determined risk groups and the occurrence of MACEs was stronger than for a CACS-CL = 5% (adjusted hazard ratio (HR): 7.24 (95% CI: 1.93-16.42) versus 3.68 (95% CI: 1.50-8.26)). Compared with the cutoff for CACS-CL = 5%, the NRI was 10.61% when using a cutoff for CACS-CL = 15%. Conclusions: Among patients with an SCP and CACS of 0, the CACS-CL model provided accurate predictions of CAD and MACEs. Compared to the cutoff for CACS-CL = 5%, the cutoff for CACS-CL = 15% seemed to be more effective and safer for deferring further CIT. Clinical Trial registration: NCT04691037.

18.
Opt Lett ; 49(3): 746-749, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38300105

RESUMO

As is well known, a light beam with a helical phase carries an optical orbital angular momentum (OAM), which can cause the orbital motion of trapped microparticles around the beam axis. Usually, the speed of the orbital motion is uniform along the azimuthal direction and depends on the amount of OAM and the light intensity. Here, we present the reverse customized method to tailor the nonuniform local OAM density along the azimuthal direction of the focal field, which has a hybrid polarization distribution and maintains a doughnut-shaped intensity profile. Theoretical analysis and experimental results about the orbital motion of the trapped polystyrene sphere show that the nonuniform local OAM density can be tailored by manipulating the polarization states of the focal field. Our results provide an ingenious way to control the local tangential optical force and the speed of the orbital motion of particles driven by the local OAM density and will promote exciting possibilities for exploring ways to control the mechanical dynamics of microparticles in optical trapping and microfluidics.

19.
Chemistry ; 30(39): e202401377, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38738789

RESUMO

(Z)-alkenes are useful synthons but thermodynamically less stable than their (E)-isomers and typically more difficult to prepare. The synthesis of 1,4-hetero-bifunctionalized (Z)-alkenes is particularly challenging due to the inherent regio- and stereoselectivity issues. Herein we demonstrate a general, chemoselective and direct synthesis of (Z)-2-butene-1,4-diol monoesters. The protocol operates within a Pd-catalyzed decarboxylative acyloxylation regime involving vinyl ethylene carbonates (VECs) and various carboxylic acids as the reaction partners under mild and operationally attractive conditions. The newly developed process allows access to a structurally diverse pool of (Z)-2-butene-1,4-diol monoesters in good yields and with excellent regio- and stereoselectivity. Various synthetic transformations of the obtained (Z)-2-butene-1,4-diol monoesters demonstrate how these synthons are of great use to rapidly diversify the portfolio of these formal desymmetrized (Z)-alkenes.

20.
Neurochem Res ; 49(8): 2005-2020, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38814357

RESUMO

Postoperative cognitive dysfunction (POCD) occurs after surgery and severely impairs patients' quality of life. Finding POCD-associated variables can aid in its diagnosis and prognostication. POCD is associated with noncoding RNAs, such as microRNAs (miRNAs), involved in metabolic function, immune response alteration, and cognitive ability impairment; however, the underlying mechanisms remain unclear. The aim of this study was to investigate hub miRNAs (i.e., miRNAs that have an important regulatory role in diseases) regulating postoperative cognitive function and the associated mechanisms. Hub miRNAs were identified by bioinformatics, and their expression in mouse hippocampus tissues was determined using real-time quantitative polymerase chain reaction. Hub miRNAs were overexpressed or knocked down in cell and animal models to test their effects on neuroinflammation and postoperative cognitive function. Six differentially expressed hub miRNAs were identified. miR-206-3p was the only broadly conserved miRNA, and it was used in follow-up studies and animal experiments. Its inhibitors reduced the release of proinflammatory cytokines in BV-2 microglia by regulating its target gene, brain-derived neurotrophic factor (BDNF), and the downstream signaling pathways. miR-206-3p inhibition suppressed microglial activation in the hippocampi of mice and improved learning and cognitive decline. Therefore, miR-206-3p significantly affects POCD, implying its potential as a therapeutic target.


Assuntos
Fator Neurotrófico Derivado do Encéfalo , Cognição , Hipocampo , Camundongos Endogâmicos C57BL , MicroRNAs , Complicações Cognitivas Pós-Operatórias , Animais , MicroRNAs/metabolismo , MicroRNAs/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Fator Neurotrófico Derivado do Encéfalo/genética , Camundongos , Complicações Cognitivas Pós-Operatórias/metabolismo , Masculino , Hipocampo/metabolismo , Cognição/fisiologia , Envelhecimento/metabolismo , Envelhecimento/genética , Microglia/metabolismo , Linhagem Celular
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