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1.
Acc Chem Res ; 57(5): 751-762, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38346006

RESUMEN

ConspectusAfter decades of palladium dominating the realm of transition-metal-catalyzed cross-coupling, recent years have witnessed exciting advances in the development of new nickel-catalyzed cross-coupling reactions to form C(sp3) centers. Nickel possesses distinct properties compared with palladium, such as facile single-electron transfer to C(sp3) electrophiles and rapid C-C reductive elimination from NiIII. These properties, among others, make nickel particularly well-suited for reductive cross-coupling (RCC) in which two electrophiles are coupled and an exogenous reductant is used to turn over the metal catalyst. Ni-catalyzed RCCs use readily available and stable electrophiles as starting materials and exhibit good functional group tolerance, which makes them appealing for applications in the synthesis of complex molecules. Building upon the foundational work in Ni-catalyzed RCCs by the groups of Kumada, Durandetti, Weix, and others, as well as the advancements in Ni-catalyzed enantioselective redox-neutral cross-couplings led by Fu and co-workers, we initiated a program to explore the feasibility of developing highly enantioselective Ni-catalyzed RCCs. Our research has also been driven by a keen interest in unraveling the factors contributing to enantioinduction and electrophile activation as we seek new avenues for advancing our understanding and further developing these reactions.In the first part of this Account, we organize our reported methods on the basis of the identity of the C(sp3) electrophiles, including benzylic chlorides, N-hydroxyphthalimide (NHP) esters, and α-chloro esters and nitriles. We highlight how the selection of specific chiral ligands plays a pivotal role in achieving high cross-selectivity and enantioselectivity. In addition, we show that reduction can be accomplished not only with heterogeneous reductants, such as Mn0, but also with the soluble organic reductant tetrakis(dimethylamino)ethylene (TDAE), as well as electrochemically. The use of homogeneous reductants, such as TDAE, is well suited for studying the mechanism of the transformation. Although this Account primarily focuses on RCCs, we also highlight our work using trifluoroborate (BF3K) salts as radical precursors for enantioselective dual-Ni/photoredox systems.At the end of this Account, we summarize the relevant mechanistic studies of two closely related asymmetric reductive alkenylation reactions developed in our laboratory and provide a context between our work and related mechanistic studies by others. We discuss how the ligand properties influence the rates and mechanisms of electrophile activation and how understanding the mode of C(sp3) radical generation can be used to optimize the yield of an RCC. Our research endeavors to offer insights on the intricate mechanisms at play in asymmetric Ni-catalyzed RCCs with the goal of using the rate of electrophile activation to improve the substrate scope of enantioselective RCCs. We anticipate that the insights we share in this Account can provide guidance for the development of new methods in this field.

2.
Arterioscler Thromb Vasc Biol ; 44(1): 254-270, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37916416

RESUMEN

BACKGROUND: Hyperglycemia-a symptom that characterizes diabetes-is highly associated with atherothrombotic complications. However, the underlying mechanism by which hyperglycemia fuels platelet activation and arterial thrombus formation is still not fully understood. METHODS: The profiles of polyunsaturated fatty acid metabolites in the plasma of patients with diabetes and healthy controls were determined with targeted metabolomics. FeCl3-induced carotid injury model was used to assess arterial thrombus formation in mice with endothelial cell (EC)-specific YAP (yes-associated protein) deletion or overexpression. Flow cytometry and clot retraction assay were used to evaluate platelet activation. RNA sequencing and multiple biochemical analyses were conducted to unravel the underlying mechanism. RESULTS: The plasma PGE2 (prostaglandin E2) concentration was elevated in patients with diabetes with thrombotic complications and positively correlated with platelet activation. The PGE2 synthetases COX-2 (cyclooxygenase-2) and mPGES-1 (microsomal prostaglandin E synthase-1) were found to be highly expressed in ECs but not in other type of vessel cells in arteries from both patients with diabetes and hyperglycemic mice, compared with nondiabetic individuals and control mice, respectively. A combination of RNA sequencing and ingenuity pathway analyses indicated the involvement of YAP signaling. EC-specific deletion of YAP limited platelet activation and arterial thrombosis in hyperglycemic mice, whereas EC-specific overexpression of YAP in mice mimicked the prothrombotic state of diabetes, without affecting hemostasis. Mechanistically, we found that hyperglycemia/high glucose-induced endothelial YAP nuclear translocation and subsequently transcriptional expression of COX-2 and mPGES-1 contributed to the elevation of PGE2 and platelet activation. Blockade of EP3 (prostaglandin E receptor 3) activation by oral administration of DG-041 reversed the hyperactivity of platelets and delayed thrombus formation in both EC-specific YAP-overexpressing and hyperglycemic mice. CONCLUSIONS: Collectively, our data suggest that hyperglycemia-induced endothelial YAP activation aggravates platelet activation and arterial thrombus formation via PGE2/EP3 signaling. Targeting EP3 with DG-041 might be therapeutic for diabetes-related thrombosis.


Asunto(s)
Diabetes Mellitus , Hiperglucemia , Trombosis , Animales , Humanos , Ratones , Plaquetas/metabolismo , Ciclooxigenasa 2/metabolismo , Diabetes Mellitus/metabolismo , Dinoprostona/metabolismo , Hiperglucemia/complicaciones , Hiperglucemia/metabolismo , Ratones Obesos , Trombosis/genética , Trombosis/metabolismo
3.
Proc Natl Acad Sci U S A ; 119(22): e2200230119, 2022 05 31.
Artículo en Inglés | MEDLINE | ID: mdl-35617432

RESUMEN

Brain metastases, including prevalent breast-to-brain metastasis (B2BM), represent an urgent unmet medical need in the care of cancer due to a lack of effective therapies. Immune evasion is essential for cancer cells to metastasize to the brain tissue for brain metastasis. However, the intrinsic genetic circuits that enable cancer cells to avoid immune-mediated killing in the brain microenvironment remain poorly understood. Here, we report that a brain-enriched long noncoding RNA (BMOR) expressed in B2BM cells is required for brain metastasis development and is both necessary and sufficient to drive cancer cells to colonize the brain tissue. Mechanistically, BMOR enables cancer cells to evade immune-mediated killing in the brain microenvironment for the development of brain metastasis by binding and inactivating IRF3. In preclinical brain metastasis murine models, locked nucleic acid-BMOR, a designed silencer targeting BMOR, is effective in suppressing the metastatic colonization of cancer cells in the brain for brain metastasis. Taken together, our study reveals a mechanism underlying B2BM immune evasion during cancer cell metastatic colonization of brain tissue for brain metastasis, where B2BM cells evade immune-mediated killing in the brain microenvironment by acquiring a brain-enriched long noncoding RNA genetic feature.


Asunto(s)
Neoplasias Encefálicas , Encéfalo , Neoplasias de la Mama , Evasión Inmune , ARN Largo no Codificante , Animales , Encéfalo/inmunología , Encéfalo/metabolismo , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/inmunología , Neoplasias Encefálicas/secundario , Mama/patología , Neoplasias de la Mama/patología , Línea Celular Tumoral , Femenino , Humanos , Evasión Inmune/genética , Ratones , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Microambiente Tumoral
4.
Biochem Biophys Res Commun ; 710: 149862, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38593618

RESUMEN

Zinc is an important trace element in the human body, and its homeostasis is closely related to amyotrophic lateral sclerosis (ALS). Cytoplasmic FUS proteins from patients with ALS aggregate their important pathologic markers. Liquid-liquid phase separation (LLPS) of FUS can lead to its aggregation. However, whether and how zinc homeostasis affects the aggregation of disease-associated FUS proteins in the cytoplasm remains unclear. Here, we found that zinc ion enhances LLPS and promotes the aggregation in the cytoplasm for FUS protein. In the FUS, the cysteine of the zinc finger (ZnF), recognizes and binds to zinc ions, reducing droplet mobility and enhancing protein aggregation in the cytoplasm. The mutation of FUS cysteine disrupts the dynamic regulatory switch of zinc ions and ZnF, resulting in insensitivity to zinc ions. These results suggest that the dynamic regulation of LLPS by binding with zinc ions may be a widespread mechanism and provide a new understanding of neurological diseases such as ALS and other ZnF protein-related diseases.


Asunto(s)
Esclerosis Amiotrófica Lateral , Proteína FUS de Unión a ARN , Humanos , Esclerosis Amiotrófica Lateral/genética , Esclerosis Amiotrófica Lateral/metabolismo , Cisteína/genética , Mutación , Separación de Fases , Proteína FUS de Unión a ARN/química , Proteína FUS de Unión a ARN/genética , Proteína FUS de Unión a ARN/metabolismo , Zinc/metabolismo , Dedos de Zinc , Agregado de Proteínas
5.
J Virol ; 97(6): e0043423, 2023 06 29.
Artículo en Inglés | MEDLINE | ID: mdl-37289052

RESUMEN

Although influenza A viruses of several subtypes have occasionally infected humans, to date only those of the H1, H2, and H3 subtypes have led to pandemics and become established in humans. The detection of two human infections by avian H3N8 viruses in April and May of 2022 raised pandemic concerns. Recent studies have shown the H3N8 viruses were introduced into humans from poultry, although their genesis, prevalence, and transmissibility in mammals have not been fully elucidated. Findings generated from our systematic influenza surveillance showed that this H3N8 influenza virus was first detected in chickens in July 2021 and then disseminated and became established in chickens over wider regions of China. Phylogenetic analyses revealed that the H3 HA and N8 NA were derived from avian viruses prevalent in domestic ducks in the Guangxi-Guangdong region, while all internal genes were from enzootic poultry H9N2 viruses. The novel H3N8 viruses form independent lineages in the glycoprotein gene trees, but their internal genes are mixed with those of H9N2 viruses, indicating continuous gene exchange among these viruses. Experimental infection of ferrets with three chicken H3N8 viruses showed transmission through direct contact and inefficient transmission by airborne exposure. Examination of contemporary human sera detected only very limited antibody cross-reaction to these viruses. The continuing evolution of these viruses in poultry could pose an ongoing pandemic threat. IMPORTANCE A novel H3N8 virus with demonstrated zoonotic potential has emerged and disseminated in chickens in China. It was generated by reassortment between avian H3 and N8 virus(es) and long-term enzootic H9N2 viruses present in southern China. This H3N8 virus has maintained independent H3 and N8 gene lineages but continues to exchange internal genes with other H9N2 viruses to form novel variants. Our experimental studies showed that these H3N8 viruses were transmissible in ferrets, and serological data suggest that the human population lacks effective immunological protection against it. With its wide geographical distribution and continuing evolution in chickens, other spillovers to humans can be expected and might lead to more efficient transmission in humans.


Asunto(s)
Subtipo H3N8 del Virus de la Influenza A , Subtipo H9N2 del Virus de la Influenza A , Gripe Aviar , Gripe Humana , Animales , Humanos , Gripe Humana/epidemiología , Pollos , Salud Pública , Subtipo H9N2 del Virus de la Influenza A/genética , Filogenia , Hurones , China/epidemiología , Aves de Corral
6.
J Transl Med ; 22(1): 465, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38755664

RESUMEN

Disturbance in mitochondrial homeostasis within proximal tubules is a critical characteristic associated with diabetic kidney disease (DKD). CaMKKß/AMPK signaling plays an important role in regulating mitochondrial homeostasis. Despite the downregulation of CaMKKß in DKD pathology, the underlying mechanism remains elusive. The expression of NEDD4L, which is primarily localized to renal proximal tubules, is significantly upregulated in the renal tubules of mice with DKD. Coimmunoprecipitation (Co-IP) assays revealed a physical interaction between NEDD4L and CaMKKß. Moreover, deletion of NEDD4L under high glucose conditions prevented rapid CaMKKß protein degradation. In vitro studies revealed that the aberrant expression of NEDD4L negatively influences the protein stability of CaMKKß. This study also explored the role of NEDD4L in DKD by using AAV-shNedd4L in db/db mice. These findings confirmed that NEDD4L inhibition leads to a decrease in urine protein excretion, tubulointerstitial fibrosis, and oxidative stress, and mitochondrial dysfunction. Further in vitro studies demonstrated that si-Nedd4L suppressed mitochondrial fission and reactive oxygen species (ROS) production, effects antagonized by si-CaMKKß. In summary, the findings provided herein provide strong evidence that dysregulated NEDD4L disturbs mitochondrial homeostasis by negatively modulating CaMKKß in the context of DKD. This evidence underscores the potential of therapeutic interventions targeting NEDD4L and CaMKKß to safeguard renal tubular function in the management of DKD.


Asunto(s)
Quinasa de la Proteína Quinasa Dependiente de Calcio-Calmodulina , Nefropatías Diabéticas , Regulación hacia Abajo , Homeostasis , Mitocondrias , Ubiquitina-Proteína Ligasas Nedd4 , Animales , Ubiquitina-Proteína Ligasas Nedd4/metabolismo , Ubiquitina-Proteína Ligasas Nedd4/genética , Nefropatías Diabéticas/metabolismo , Nefropatías Diabéticas/patología , Mitocondrias/metabolismo , Quinasa de la Proteína Quinasa Dependiente de Calcio-Calmodulina/metabolismo , Ratones Endogámicos C57BL , Ratones , Humanos , Especies Reactivas de Oxígeno/metabolismo , Masculino , Estrés Oxidativo , Dinámicas Mitocondriales , Estabilidad Proteica , Proteolisis
7.
Opt Lett ; 49(11): 3034-3037, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38824321

RESUMEN

Terahertz (THz) radiation from air plasma in the presence of pre-plasma in a collinear geometry is investigated experimentally, where the pre-plasma is formed by a pre-pulse with a Gaussian beam profile and the measured THz radiation is driven by a main laser pulse. The pre-plasma has a de-focusing effect for the main pulse passing through it, which reduces the effective length of the plasma filament formed by the main laser pulse for THz radiation. It is found that only the part not overlapped by the pre-plasma can actually produce THz radiation. Thus, the amplitude of the THz pulse driven by the main pulse can be modified by changing the spatial separation between two plasma filaments. The experimental observations are qualitatively in agreement with our numerical simulation results. It is also found that the change of the time delay between the pre-pulse and the main pulse does not change the THz radiation amplitude for a given spatial separation. This study suggests a practical way for the manipulation of THz waves through an interaction between laser plasma filaments.

8.
Phys Rev Lett ; 132(16): 165002, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38701476

RESUMEN

We report the experimental measurement of millijoule terahertz (THz) radiation emitted in the backward direction from laser wakefields driven by a femtosecond laser pulse of few joules interacting with a gas target. By utilizing frequency-resolved energy measurement, it is found that the THz spectrum exhibits two peaks located at about 4.5 and 9.0 THz, respectively. In particular, the high frequency component emerges when the drive laser energy exceeds 1.26 J, at which electron acceleration in the forward direction is detected simultaneously. Theoretical analysis and particle-in-cell simulations indicate that the THz radiation is generated via mode conversion from the laser wakefields excited in plasma with an up-ramp profile, where radiations both at the local electron plasma frequency and its harmonics are produced. Such intense THz sources may find many applications in ultrafast science, e.g., manipulating the transient states of matter.

9.
Environ Sci Technol ; 58(1): 410-420, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38154084

RESUMEN

SiO2 nanoparticles (SiO2NPs) are most widely available and coexisting with DOM at the mineral-water interface; however, the role of SiO2NPs in DOM fractionation and the underlying mechanisms have not been fully understood. Using Fourier transform ion cyclotron resonance mass spectrometry, combined with Fourier transform infrared spectroscopy and X-ray adsorption fine structure spectroscopy, was employed to investigate the adsorptive fractionation of litter layer-derived DOM on goethite coexisting with SiO2NPs under different pH conditions. Results indicated that the inhibitory effect of the coexisting SiO2NPs on OM sorbed by goethite was waning as environmental pH increased due to the reduced steric interactions and the concurrent elevated hydrogen bonding/hydrophobic partitioning interactions on the goethite surface. We observed the coexisting SiO2NPs inhibited the adsorption of high carboxylic-containing condensed aromatic/aromatics compounds on goethite under different pH conditions while improving the adsorption of highly unsaturated aliphatic/phenolic and carbohydrate-like compounds in an alkaline and/or circumneutral environment. More nitrogen-containing structures may favor the adsorption of phenolic and nonaromatic compounds to goethite by counteracting the negative effect of SiO2NPs. These findings suggest that DOM sequestration may be significantly regulated by the coexisting SiO2NPs at the mineral-water interface, which may further influence the carbon-nitrogen cycling and contaminant fate in natural environments.


Asunto(s)
Materia Orgánica Disuelta , Dióxido de Silicio , Adsorción , Minerales/química , Compuestos Orgánicos , Fenoles , Agua , Nitrógeno
10.
Appl Opt ; 63(12): 3219-3227, 2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38856470

RESUMEN

This paper presents an adaptive focus stacking method for large depth-of-field (DOF) 3D microscopic structured-light imaging systems. Conventional focus stacking methods typically capture images under a series of pre-defined focus settings without considering the attributes of the measured object. Therefore, it is inefficient since some of the focus settings might be redundant. To address this problem, we first employ the focal sweep technique to reconstruct an initial rough 3D shape of the measured objects. Then, we leverage the initial 3D data to determine effective focus settings that focus the camera on the valid areas of the measured objects. Finally, we reconstruct a high-quality 3D point cloud using fringe images obtained from these effective focus settings by focus stacking. Experimental results demonstrate the success of the proposed method.

11.
BMC Public Health ; 24(1): 1787, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38965484

RESUMEN

BACKGROUND: Abnormal heart rate recovery (HRR), representing cardiac autonomic dysfunction, is an important predictor of cardiovascular disease. Prolonged sedentary time (ST) is associated with a slower HRR. However, it is not clear how much moderate-to-vigorous physical activity (MVPA) is required to mitigate the adverse effects of sedentary behavior on HRR in young and middle-aged adults. This study aimed to examine the joint association of ST and MVPA with abnormal HRR in this population. METHODS: A cross-sectional analysis was conducted on 1253 participants (aged 20-50 years, 67.8% male) from an observational study assessing cardiopulmonary fitness in Fujian Province, China. HRR measured via cardiopulmonary exercise tests on a treadmill was calculated as the difference between heart rate at peak exercise and 2 min after exercise. When the HRR was ≤ 42 beats·minute-1 within this time, it was considered abnormal. ST and MVPA were assessed by the IPAQ-LF. Individuals were classified as having a low sedentary time (LST [< 6 h·day-1]) or high sedentary time (HST [≥ 6 h·day-1]) and according to their MVPA level (low MVPA [0-149 min·week-1], medium MVPA [150-299 min·week-1], high MVPA [≥ 300 min·week-1]). Finally, six ST-MVPA groups were derived. Associations between ST-MVPA groups with abnormal HRR incidence were examined using logistic regression models. RESULTS: 53.1% of the young and middle-aged adults had less than 300 min of MVPA per week. In model 2, adjusted for possible confounders (e.g. age, sex, current smoking status, current alcohol consumption, sleep status, body mass index), HST was associated with higher odds of an abnormal HRR compared to LST (odds ratio (OR) = 1.473, 95% confidence interval (CI) = 1.172-1.852). Compared with the reference group (HST and low MVPA), the HST and high MVPA groups have a lower chance of abnormal HRR (OR, 95% CI = 0.553, 0.385-0.795). Compared with individuals with HST and low MVPA, regardless of whether MVPA is low, medium, or high, the odds of abnormal HRR in individuals with LST is significantly reduced (OR, 95% CI = 0.515, 0.308-0.857 for LST and low MVPA; OR, 95% CI = 0.558, 0.345-0.902 for LST and medium MVPA; OR, 95% CI = 0.476, 0.326-0.668 for LST and high MVPA). CONCLUSION: Higher amounts of MVPA appears to mitigate the increased odds of an abnormal HRR associated with HST for healthy young and middle-aged adults.


Asunto(s)
Ejercicio Físico , Frecuencia Cardíaca , Conducta Sedentaria , Humanos , Masculino , Femenino , Adulto , Estudios Transversales , Frecuencia Cardíaca/fisiología , Persona de Mediana Edad , Ejercicio Físico/fisiología , China/epidemiología , Adulto Joven , Prueba de Esfuerzo
12.
Mol Med ; 29(1): 72, 2023 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-37280526

RESUMEN

BACKGROUND: Mitochondrial metabolism has been proposed as an attractive target for breast cancer therapy. The discovery of new mechanisms underlying mitochondrial dysfunction will facilitate the development of new metabolic inhibitors to improve the clinical treatment of breast cancer patients. DYNLT1 (Dynein Light Chain Tctex-Type 1) is a key component of the motor complex that transports cellular cargo along microtubules in the cell, but whether and how DYNLT1 affects mitochondrial metabolism and breast cancer has not been reported. METHODS: The expression levels of DYNLT1 were analyzed in clinical samples and a panel of cell lines. The role of DYNLT1 in breast cancer development was investigated using in vivo mouse models and in vitro cell assays, including CCK-8, plate cloning and transwell assay. The role of DYNLT1 in regulating mitochondrial metabolism in breast cancer development is examined by measuring mitochondrial membrane potential and ATP levels. To investigate the underlying molecular mechanism, many methods, including but not limited to Co-IP and ubiquitination assay were used. RESULTS: First, we found that DYNLT1 was upregulated in breast tumors, especially in ER + and TNBC subtypes. DYNLT1 promotes the proliferation, migration, invasion and mitochondrial metabolism in breast cancer cells in vitro and breast tumor development in vivo. DYNLT1 colocalizes with voltage-dependent anion channel 1 (VDAC1) on mitochondria to regulate key metabolic and energy functions. Mechanistically, DYNLT1 stabilizes the voltage-dependent anion channel 1 (VDAC1) by hindering E3 ligase Parkin-mediated VDAC1 ubiquitination and degradation. CONCLUSION: Our data demonstrate that DYNLT1 promotes mitochondrial metabolism to fuel breast cancer development by inhibiting Parkin-mediated ubiquitination degradation of VDAC1. This study suggests that mitochondrial metabolism can be exploited by targeting the DYNLT1-Parkin-VDAC1 axis to improve the ability of metabolic inhibitors to suppress cancers with limited treatment options, such as triple-negative breast cancer (TNBC).


Asunto(s)
Neoplasias de la Mama Triple Negativas , Canal Aniónico 1 Dependiente del Voltaje , Animales , Humanos , Ratones , Apoptosis , Dineínas/metabolismo , Mitocondrias/metabolismo , Ubiquitina-Proteína Ligasas , Ubiquitinación , Canal Aniónico 1 Dependiente del Voltaje/genética , Canal Aniónico 1 Dependiente del Voltaje/metabolismo
13.
Small ; 19(38): e2302015, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37222119

RESUMEN

Heterojunctions are a promising class of materials for high-efficiency bifunctional oxygen electrocatalysts in both oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). However, the conventional theories fail to explain why many catalysts behave differently in ORR and OER, despite a reversible path (* O2 ⇋* OOH⇋* O⇋* OH). This study proposes the electron-/hole-rich catalytic center theory (e/h-CCT) to supplement the existing theories, it suggests that the Fermi level of catalysts determines the direction of electron transfer, which affects the direction of the oxidation/reduction reaction, and the density of states (DOS) near the Fermi level determines the accessibility for injecting electrons and holes. Additionally, heterojunctions with different Fermi levels form electron-/hole-rich catalytic centers near the Fermi levels to promote ORR/OER, respectively. To verify the universality of the e/h-CCT theory, this study reveals the randomly synthesized heterostructural Fe3 N-FeN0.0324 (Fex N@PC with DFT calculations and electrochemical tests. The results show that the heterostructural F3 N-FeN0.0324 facilitates the catalytic activities for ORR and OER simultaneously by forming an internal electron-/hole-rich interface. The rechargeable ZABs with Fex N@PC cathode display a high open circuit potential of 1.504 V, high power density of 223.67 mW cm-2 , high specific capacity of 766.20 mAh g-1 at 5 mA cm-2 , and excellent stability for over 300 h.

14.
Opt Lett ; 48(16): 4348-4351, 2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37582029

RESUMEN

This Letter presents a novel, to the best of our knowledge, method to calibrate multi-focus microscopic structured-light three-dimensional (3D) imaging systems with an electrically adjustable camera focal length. We first leverage the conventional method to calibrate the system with a reference focal length f0. Then we calibrate the system with other discrete focal lengths fi by determining virtual features on a reconstructed white plane using f0. Finally, we fit the polynomial function model using the discrete calibration results for fi. Experimental results demonstrate that our proposed method can calibrate the system consistently and accurately.

15.
Phys Rev Lett ; 130(21): 215001, 2023 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-37295115

RESUMEN

Curved plasma channels have been proposed to guide intense lasers for various applications, such as x-ray laser emission, compact synchrotron radiation, and multistage laser wakefield acceleration [e.g. J. Luo et al., Phys. Rev. Lett. 120, 154801 (2018)PRLTAO0031-900710.1103/PhysRevLett.120.154801]. Here, a carefully designed experiment shows evidences of intense laser guidance and wakefield acceleration in a centimeter-scale curved plasma channel. Both experiments and simulations indicate that when the channel curvature radius is gradually increased and the laser incidence offset is optimized, the transverse oscillation of the laser beam can be mitigated, and the stably guided laser pulse excites wakefields and accelerates electrons along the curved plasma channel to a maximum energy of 0.7 GeV. Our results also show that such a channel exhibits good potential for seamless multistage laser wakefield acceleration.


Asunto(s)
Aceleración , Electrones , Frecuencia Cardíaca , Rayos Láser , Plasma
16.
Diabetes Metab Res Rev ; 39(4): e3616, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36657181

RESUMEN

AIMS: To develop and validate a risk prediction model for Chinese patients with type 2 diabetes with the recurrence of diabetic foot ulcers (DFUs) based on a systematic review and meta-analysis. METHODS: A prospective analysis was performed with 1333 participants and followed up for 60 months. Three models were analysed using a derived cohort. The risk factors were screened using meta-analysis and logistic regression, and the missing variables were interpolated by multiple imputation. The internal validation was performed using the bootstrap procedure, and the validation cohort was applied to the external validation. The performance of the model was evaluated in the area under the discrimination Receiver Operating Characteristic Curve (ROC). Calibration and discrimination methods were used for the validation cohort. The variables were selected according to their clinical and statistical importance to construct the nomograms. RESULTS: Three models were developed and validated. Model 1 included seven social and clinical indicators like sex, diabetes mellitus duration, previous DFU, location of ulcer, smoking, history of amputation, and foot deformity. Model 2 included four more indicators besides those in Model 1, which were statin agents used, antiplatelet agents used, systolic blood pressure, and body mass index. Model 3 added further laboratory indicators to Model 2, such as LDL-C, HbA1C, fibrinogen, and blood urea nitrogen. In the derivation cohort, 20.1% (206/1027) participants with DFU recurred as compared to the validation cohort, which was 38.2% (117/306). The areas under the curve in the derivation cohort for Models 1-3 were 0.781 (0.744-0.817), 0.843 (0.813-0.873), and 0.899 (0.876-0.922), respectively. The Youden indexes for Models 1-3 were 0.430, 0.559, and 0.653, respectively. Model 3 showed the highest sensitivity and specificity. All models performed well for both discrimination and calibration. CONCLUSIONS: Models 1-2 were non-invasive, which indicate their role in general screening for patients at a high risk of recurrence of DFU. However, Model 3 offers a more specific screening due to its best performance in predicting the risk of DFU recurrence amongst the three models.


Asunto(s)
Diabetes Mellitus Tipo 2 , Pie Diabético , Úlcera del Pie , Humanos , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/diagnóstico , Estudios Longitudinales , Pie Diabético/diagnóstico , Pie Diabético/epidemiología , Pie Diabético/etiología , Estudios de Cohortes , Factores de Riesgo
17.
Eur J Nucl Med Mol Imaging ; 50(5): 1360-1370, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36631715

RESUMEN

BACKGROUND: Fibrosis and inflammation are major pathological changes of Crohn's disease (CD). Early detection and accurate severity evaluation of CD are critical for patient's prognosis. Endoscopy is widely used to evaluate CD progression. Herein, we evaluated the efficacy of [68Ga]Ga-FAPI-04 PET/CT to identify lesions and assess the progression of CD. METHODS: All CD patients received computed tomography enterography (CTE), [68Ga]Ga-FAPI-04 PET/CT examination, and ileocolonoscopy within 1 week. Two independent gastroenterologists computed the Crohn's disease activity index (CDAI) of all patients. Two radiology physicians assessed the CTE images separately, and the CTE scores were calculated. Lastly, two nuclear medicine physicians independently examined the [68Ga]Ga-FAPI-04 PET/CT images. Once the FAPI uptake of the intestinal segment was equal or higher relative to the liver (considered FAPI-positive), the target-to-background ratio (TBR) and global FAPI PET/CT score were computed, representing the independent intestinal activity and activity of all intestinal segments, respectively. Levels of fecal calprotectin (FCP) and C-reactive protein (CRP) were determined before the endoscopy. The Crohn's disease endoscopy index of severity (CDEIS) and the simple endoscopic score for Crohn's disease (SES-CD) were calculated during the endoscopy. Finally, all data were obtained and analyzed. RESULTS: There were 74 intestinal segments in 16 patients were assessed. [68Ga]Ga-FAPI-04 PET/CT identified 42 of 45 endoscopically lesioned segments (endoscopic lesions detection sensitivity: 93.3%), while CTE identified 39 of them (endoscopic lesions detection sensitivity: 86.7%). According to the receiver operating characteristic (ROC) analysis, [68Ga]Ga-FAPI-04 PET/CT showed better performance in the detection of endoscopic lesions compared with CTE (P < 0.05). The TBR was significantly associated with the CTE score (r = 0.81; (95% CI): 0.736-0.869; P < 0.0001) and SES-CD values (r = 0.86; (95% CI): 0.776-0.908; P < 0.0001). In addition, the global FAPI PET/CT score was significantly correlated with FCP (r = 0.52; 95% CI, 0.02-0.81; P = 0.039), CRP (r = 0.60; 95% CI, 0.13-0.85; P = 0.014), CDEIS (r = 0.55; 95% CI, 0.06-0.83; P = 0.028), and CDAI (r = 0.81; 95% CI, 0.50-0.93; P < 0.0001). CONCLUSION: In summary, [68Ga]Ga-FAPI-04 PET/CT correlated well with endoscopic, CTE, clinical, and biomarkers of CD. It was also highly sensitive in the detection of different classes of lesions in all intestinal segments, and unlike other examinations, this technique required no patient fasting or bowel preparation. Therefore, [68Ga]Ga-FAPI-04 PET/CT may be a promising method for assessing the activity of CD.


Asunto(s)
Enfermedad de Crohn , Quinolinas , Humanos , Enfermedad de Crohn/diagnóstico por imagen , Tomografía Computarizada por Tomografía de Emisión de Positrones , Radioisótopos de Galio , Proteína C-Reactiva/análisis
18.
Mol Pharm ; 20(5): 2714-2725, 2023 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-37010328

RESUMEN

Renal fibrosis is the most common pathological feature and common pathway of progression in chronic kidney disease (CKD). We evaluated [68Ga]Ga-FAPI-04 small animal positron emission tomography/computed tomography (PET/CT) and biomarkers as noninvasive assessments of renal fibrosis (RF) in CKD rats to generate new ideas for clinical diagnosis. A rat model of renal fibrosis was administered adenine by gavage (n = 28), and the control group was given 0.9% NaCl by gavage (n = 20). At different time points (weeks 1, 2, 4, and 6), five rats were randomly selected from the two groups for [68Ga]Ga-FAPI-04 small animal PET/CT imaging. At the same time, the expression of Fibroblast activation protein (FAP) in renal tissue and the expression levels of type III procollagen N-terminal peptide (PIIINP), transforming growth factor (TGF-ß1), Klotho, and sex-determining region Y-box protein 9 (SOX9) in blood and urine were determined. FAP was highly expressed in the renal tissue of rats in the CKD group and expression increased with the progression of renal fibrosis. [68Ga]Ga-FAPI-04 small animal PET/CT examination showed that the uptake of radioactive tracers in the CKD group was higher than that in the control group, and SUVmax (r = 0.9405) and target-to-background ratio (TBR) (r = 0.9392) were positively correlated with renal fibrosis. The serum levels of PIIINP, TGF-ß1, and SOX9 in CKD rats were significantly higher than those in the control group and were positively correlated with RF (r = 0.8234, r = 0.7733, and r = 0.7135, respectively) and SUVmax (r = 0.8412, r = 0.7763, and r = 0.6814, respectively). Compared with the control group, the level of serum Klotho decreased and was negatively correlated with RF (r = -0.6925) and SUVmax (r = -0.6322). Compared with the control group, the levels of PIIINP and TGF-ß1 in urine were positively correlated with RF (r = 0.8127 and r = 0.8077, respectively) and SUVmax (r = 0.8400 and r = 0.8177, respectively). Urine Klotho decreased compared with the control group and was negatively correlated with RF (r = -0.5919) and SUVmax (r = -0.5995). The change in urine SOX9 was not statistically significant. In conclusion, compared with renal biopsy, [68Ga]Ga-FAPI-04 small animal PET/CT shows renal fibrosis quickly and noninvasively. PIIINP, TGF-ß1, and Klotho in serum and urine may be used as biomarkers of RF, and serum SOX9 is expected to become a new diagnostic biomarker of RF.


Asunto(s)
Radioisótopos de Galio , Quinolinas , Animales , Ratas , Tomografía Computarizada por Tomografía de Emisión de Positrones , Factor de Crecimiento Transformador beta1 , Biomarcadores , Fluorodesoxiglucosa F18
19.
J Org Chem ; 88(2): 1003-1017, 2023 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-36626186

RESUMEN

We report a metal-, acid-, and base-free 2-(bromomethyl)naphthalene (2-BMN)-promoted organocatalytic Cloke-Wilson rearrangement of chain doubly activated cyclopropanes for the construction of 2,3-dihydrofurans via a carbocation-initiated tandem intramolecular ring-opening/recyclization process. The strategy is especially suitable for the construction of furan units in complex molecules, providing a solution to the problem of heavy-metal residues in dihydrofuran-containing drugs synthesized by traditional metal-based protocols. Thus, it is of potential interest in synthetic and medicinal chemistry.

20.
Environ Sci Technol ; 57(10): 4367-4378, 2023 03 14.
Artículo en Inglés | MEDLINE | ID: mdl-36791305

RESUMEN

Although conductive materials have been shown to improve efficiency in anaerobic digestion (AD) by modifying microbial interactions, the interacting network under thermophilic conditions has not been examined. To identify the true taxon-taxon associations within thermophilic anaerobic digestion (TAD) microbiome and reveal the influence of carbon cloth (CC) addition, we sampled micron-scale single flocs (40-70 µm) randomly isolated from lab-scale thermophilic digesters. Results revealed that CC addition not only significantly boosted methane yield by 25.3% but also increased the spatial heterogeneity of the community in the sludge medium. After CC addition, an evident translocation of Pseudomonas from the medium to the biofilm was observed, showing their remarkable capacity for biofilm formation. Additionally, Clostridium and Thermotogaceae tightly aggregated and steadily co-occurred in the medium and biofilm of the TAD microbiome, which might be associated with their unique extracellular sugar metabolizing style. Finally, CC induced syntrophic interaction between Syntrophomonas and denitrifiers of Rhodocyclaceae. The upregulated respiration-associated electron transferring genes (Cyst-c, complex III) on the cellular membranes of these collaborating partners indicated a potential coupling of the denitrification pathway with syntrophic acetate oxidation via direct interspecies electron transfer (DIET). These findings provide an insight into how conductive materials promote thermophilic digestion performance and open the path for improved community monitoring of biotreatment systems.


Asunto(s)
Reactores Biológicos , Carbono , Anaerobiosis , Transporte de Electrón , Aguas del Alcantarillado , Interacciones Microbianas , Secuenciación de Nucleótidos de Alto Rendimiento , Metano
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