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1.
World J Stem Cells ; 16(4): 334-352, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38690516

RESUMO

Wound repair is a complex challenge for both clinical practitioners and researchers. Conventional approaches for wound repair have several limitations. Stem cell-based therapy has emerged as a novel strategy to address this issue, exhibiting significant potential for enhancing wound healing rates, improving wound quality, and promoting skin regeneration. However, the use of stem cells in skin regeneration presents several challenges. Recently, stem cells and biomaterials have been identified as crucial components of the wound-healing process. Combination therapy involving the development of biocompatible scaffolds, accompanying cells, multiple biological factors, and structures resembling the natural extracellular matrix (ECM) has gained considerable attention. Biological scaffolds encompass a range of biomaterials that serve as platforms for seeding stem cells, providing them with an environment conducive to growth, similar to that of the ECM. These scaffolds facilitate the delivery and application of stem cells for tissue regeneration and wound healing. This article provides a comprehensive review of the current developments and applications of biological scaffolds for stem cells in wound healing, emphasizing their capacity to facilitate stem cell adhesion, proliferation, differentiation, and paracrine functions. Additionally, we identify the pivotal characteristics of the scaffolds that contribute to enhanced cellular activity.

2.
Cureus ; 16(5): e60180, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38746489

RESUMO

Actinomycosis is a chronic granulomatous disease that can affect various parts of the body, including the head and neck, lungs, abdominal and pelvic cavities, and wounds. It is caused by different actinomycetes like Actinomyces sherdii, Actinomyces glasii, Actinomyces cariosa, Actinomyces zurichensis, and Actinomyces europaea. Reported infections caused by actinomycetes include pulmonary actinomycosis, pelvic and abdominal infections, bone or artificial joint infections, endocarditis, complicated urinary tract infections, and soft tissue abscesses. The combination of pulmonary actinomycosis with gastric cancer is exceptionally rare in clinical practice, and the presence of actinomycetal infection alongside tumors in elderly patients poses significant challenges in treatment. This article presents the diagnosis and treatment process of an elderly patient with pulmonary actinomycosis and gastric adenocarcinoma.

3.
Nat Commun ; 15(1): 4009, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38740761

RESUMO

Frequency combs, specialized laser sources emitting multiple equidistant frequency lines, have revolutionized science and technology with unprecedented precision and versatility. Recently, integrated frequency combs are emerging as scalable solutions for on-chip photonics. Here, we demonstrate a fully integrated superconducting microcomb that is easy to manufacture, simple to operate, and consumes ultra-low power. Our turnkey apparatus comprises a basic nonlinear superconducting device, a Josephson junction, directly coupled to a superconducting microstrip resonator. We showcase coherent comb generation through self-started mode-locking. Therefore, comb emission is initiated solely by activating a DC bias source, with power consumption as low as tens of picowatts. The resulting comb spectrum resides in the microwave domain and spans multiple octaves. The linewidths of all comb lines can be narrowed down to 1 Hz through a unique coherent injection-locking technique. Our work represents a critical step towards fully integrated microwave photonics and offers the potential for integrated quantum processors.

4.
Trials ; 25(1): 252, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38605376

RESUMO

BACKGROUND: Inappropriate eating behaviors, particularly a lack of food diversity and poor diet quality, have a significant impact on the prognosis of certain chronic conditions and exacerbate these conditions in the community-dwelling elderly population. Current dietary interventions for the elderly have not adequately considered the nutritional needs associated with multiple chronic conditions and personal dietary preferences of elderly individuals. A personalized recommendation system has been recognized as a promising approach to address this gap. However, its effectiveness as a component of an elderly-targeted dietary intervention in real-world settings remains unknown. Additionally, it is unclear whether this intervention approach will be user-friendly for the elderly. Therefore, this study aims to examine the effectiveness of a personalized meal recommendation system designed to improve dietary behavior in community-dwelling elders. The implementation process in terms of System usability and satisfaction will also be assessed. METHODS: The trial has been designed as a 6-month, non-blinded, parallel two-arm trial. One hundred fifty community-dwelling elders who meet the eligibility criteria will be enrolled. Subjects will be allocated to either the intervention group, receiving personalized meal recommendations and access to corresponding food provided as one component of the intervention, as well as health education on elder nutrition topics, or the control group, which will receive nutritional health education lectures. Outcomes will be measured at three time points: baseline at 0 months, 3 months, and 6 months. The primary outcomes will include dietary diversity (DDS) and diet quality (CDGI-E) of enrolled community-dwelling elders, representing their dietary behavior improvement, along with dietary behavior adherence to recommended meals. Secondary outcomes will measure the perceived acceptability and usability of the personalized meal recommendation system for the intervention group. Exploratory outcomes will include changes in the nutritional status and anthropometric measurements of the community-dwelling elders. DISCUSSION: This study aims to examine the effectiveness, acceptability, and usability of a personalized meal recommendation system as a data-driven dietary intervention to benefit community-dwelling elders. The successful implementation will inform the future development and integration of digital health strategies in daily nutrition support for the elderly. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR2300074912. Registered on August 20, 2023, https://www.chictr.org.cn/showproj.html?proj=127583.


Assuntos
Vida Independente , Estado Nutricional , Humanos , Idoso , Dieta/efeitos adversos , Refeições , China , Ensaios Clínicos Controlados Aleatórios como Assunto
5.
Nat Nanotechnol ; 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38684808

RESUMO

Ferrotoroidicity-the fourth form of primary ferroic order-breaks both space and time-inversion symmetry. So far, direct observation of ferrotoroidicity in natural materials remains elusive, which impedes the exploration of ferrotoroidic phase transitions. Here we overcome the limitations of natural materials using an artificial nanomagnet system that can be characterized at the constituent level and at different effective temperatures. We design a nanomagnet array as to realize a direct-kagome spin ice. This artificial spin ice exhibits robust toroidal moments and a quasi-degenerate ground state with two distinct low-temperature toroidal phases: ferrotoroidicity and paratoroidicity. Using magnetic force microscopy and Monte Carlo simulation, we demonstrate a phase transition between ferrotoroidicity and paratoroidicity, along with a cross-over to a non-toroidal paramagnetic phase. Our quasi-degenerate artificial spin ice in a direct-kagome structure provides a model system for the investigation of magnetic states and phase transitions that are inaccessible in natural materials.

6.
J Med Virol ; 96(4): e29587, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38587204

RESUMO

Obesity has been identified as an independent risk factor for severe outcomes in humans with coronavirus disease 2019 (COVID-19) and other infectious diseases. Here, we established a mouse model of COVID-19 using the murine betacoronavirus, mouse hepatitis virus 1 (MHV-1). C57BL/6 and C3H/HeJ mice exposed to MHV-1 developed mild and severe disease, respectively. Obese C57BL/6 mice developed clinical manifestations similar to those of lean controls. In contrast, all obese C3H/HeJ mice succumbed by 8 days postinfection, compared to a 50% mortality rate in lean controls. Notably, both lean and obese C3H/HeJ mice exposed to MHV-1 developed lung lesions consistent with severe human COVID-19, with marked evidence of diffuse alveolar damage (DAD). To identify early predictive biomarkers of worsened disease outcomes in obese C3H/HeJ mice, we sequenced RNA from whole blood 2 days postinfection and assessed changes in gene and pathway expression. Many pathways uniquely altered in obese C3H/HeJ mice postinfection aligned with those found in humans with severe COVID-19. Furthermore, we observed altered gene expression related to the unfolded protein response and lipid metabolism in infected obese mice compared to their lean counterparts, suggesting a role in the severity of disease outcomes. This study presents a novel model for studying COVID-19 and elucidating the mechanisms underlying severe disease outcomes in obese and other hosts.


Assuntos
COVID-19 , Vírus da Hepatite Murina , Humanos , Camundongos , Animais , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos C3H , Vírus da Hepatite Murina/genética , COVID-19/complicações , Obesidade/complicações , Perfilação da Expressão Gênica
7.
Nano Lett ; 24(14): 4108-4116, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38536003

RESUMO

Symmetry breaking plays a pivotal role in unlocking intriguing properties and functionalities in material systems. For example, the breaking of spatial and temporal symmetries leads to a fascinating phenomenon: the superconducting diode effect. However, generating and precisely controlling the superconducting diode effect pose significant challenges. Here, we take a novel route with the deliberate manipulation of magnetic charge potentials to realize unconventional superconducting flux-quantum diode effects. We achieve this through suitably tailored nanoengineered arrays of nanobar magnets on top of a superconducting thin film. We demonstrate the vital roles of inversion antisymmetry and its breaking in evoking unconventional superconducting effects, namely a magnetically symmetric diode effect and an odd-parity magnetotransport effect. These effects are nonvolatilely controllable through in situ magnetization switching of the nanobar magnets. Our findings promote the use of antisymmetry (breaking) for initiating unconventional superconducting properties, paving the way for exciting prospects and innovative functionalities in superconducting electronics.

8.
J Cancer Res Clin Oncol ; 150(2): 65, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38300308

RESUMO

BACKGROUND: Extramedullary plasmacytoma (EMP) is a rare plasma cell malignancy, especially when the tumor originates in skeletal muscle. Plasmablastic plasmacytoma is an anaplastic round cell tumor with highly malignancy and poor prognosis. To date, there have been no reports on the transformation of skeletal muscle EMP into plasmablastic plasmacytoma. Therefore, the diagnosis, treatment, and prognosis of cases of this pathologic transformation are unclear. CASE PRESENTATION: This article reports a case of an elderly male patient who presented with a painless mass in the right calf and was diagnosed with EMP by puncture pathology. Complete remission was obtained after sequential chemoradiotherapy. 6 months later, another puncture was performed due to plasmablastic plasmacytoma multiple distant metastases, and the pathology showed that EMP was transformed to plasmablastic plasmacytoma. Despite aggressive antitumor therapy, the disease continued to deteriorate, and the patient ultimately died of respiratory failure. CONCLUSION: The transformation of EMP into plasmablastic plasmacytoma is very rare, and its diagnosis and treatment require the participation of both experienced pathologists and clinicians. We report this case in order to raise clinicians' awareness of the diagnosis and treatment of EMP and its transformation to plasmablastic plasmacytoma, and to avoid misdiagnosis and underdiagnosis.


Assuntos
Plasmocitoma , Idoso , Masculino , Humanos , Plasmocitoma/diagnóstico , Plasmocitoma/terapia , Quimiorradioterapia , Morte , Músculo Esquelético , Resposta Patológica Completa
9.
Nat Commun ; 15(1): 1119, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38321010

RESUMO

The metasurface platform with time-varying characteristics has emerged as a promising avenue for exploring exotic physics associated with Floquet materials and for designing photonic devices like linear frequency converters. However, the limited availability of materials with ultrafast responses hinders their applications in the terahertz range. Here we present a time-varying metasurface comprising an array of superconductor-metal hybrid meta-molecules. Each meta-molecule consists of two meta-atoms that are "bonded" together by double superconducting microbridges. Through experimental investigations, we demonstrate high-efficiency linear terahertz frequency conversion by rapidly breaking the bond using a coherent ultrashort terahertz pump pulse. The frequency and relative phase of the converted wave exhibit strong dependence on the pump-probe delay, indicating phase controllable wave conversion. The dynamics of the meta-molecules during the frequency conversion process are comprehensively understood using a time-varying coupled mode model. This research not only opens up new possibilities for developing innovative terahertz sources but also provides opportunities for exploring topological dynamics and Floquet physics within metasurfaces.

10.
Sci Adv ; 10(8): eadj2566, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38381814

RESUMO

The studies of number sense in different species are severely hampered by the inevitable entanglement of non-numerical attributes inherent in nonsymbolic stimuli representing numerosity, resulting in contrasting theories of numerosity processing. Here, we developed an algorithm and associated analytical methods to generate stimuli that not only minimized the impact of non-numerical magnitudes in numerosity perception but also allowed their quantification. We trained number-naïve rats with these stimuli as sound pulses representing two or three numbers and demonstrated that their numerical discrimination ability mainly relied on numerosity. Also, studying the learning process revealed that rats used numerosity before using magnitudes for choices. This numerical processing could be impaired specifically by silencing the posterior parietal cortex. Furthermore, modeling this capacity by neural networks shed light on the separation of numerosity and magnitudes extraction. Our study helps dissect the relationship between magnitude and numerosity processing, and the above different findings together affirm the independent existence of innate number and magnitudes sense in rats.


Assuntos
Cognição , Conceitos Matemáticos , Animais , Ratos , Redes Neurais de Computação , Aprendizagem , Algoritmos
11.
Cancer Biother Radiopharm ; 39(4): 318-321, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38324046

RESUMO

Background: Malignant glomus tumors (MGTs) are rare malignancies, which grow rapidly and are aggressive. Surgical resection has been regarded as the standard management, but treatment options for those unresectable tumors are limited, resulting in a high recurrence rate and poor prognosis. Case Description: An 85-year-old man presented with gross hematuria and was diagnosed with MGTs of bladder. The patient achieved long-term local control after multimodal therapy comprising radiotherapy, iodine-125 seeds brachytherapy, transcatheter arterial chemoembolization, and antiangiogenic targeted therapy. Conclusion: MGTs occurring in the bladder are clinically rare and refractory. The case presented here highlights the importance of multidisciplinary diagnosis and treatment, providing evidence that radiotherapy and antiangiogenic therapy may play an important role in unresectable bladder MGT.


Assuntos
Tumor Glômico , Neoplasias da Bexiga Urinária , Humanos , Masculino , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/radioterapia , Neoplasias da Bexiga Urinária/terapia , Neoplasias da Bexiga Urinária/tratamento farmacológico , Idoso de 80 Anos ou mais , Tumor Glômico/patologia , Terapia Combinada/métodos
12.
Artigo em Inglês | MEDLINE | ID: mdl-38366015

RESUMO

BACKGROUND: The association between magnesium status and metabolic syndrome remains unclear. This study aimed to examine the relationship between the kidney reabsorption-related magnesium depletion score (MDS) and metabolic syndrome among US adults. METHODS: We analyzed data from 15,565 adults participating in the National Health and Nutrition Examination Survey (NHANES) 2003-2018. Metabolic syndrome was defined according to the National Cholesterol Education Program's Adult Treatment Panel III report. The MDS is a scoring system developed to predict the status of magnesium deficiency that fully considers the pathophysiological factors influencing the kidneys' reabsorption capability. Weighted univariate and multivariate logistic regression were used to assess the association between MDS and metabolic syndrome. Restricted cubic spline analysis was conducted to characterize dose-response relationships. Stratified analyses by sociodemographic and lifestyle factors were also performed. RESULTS: In both univariate and multivariate analyses, higher MDS was significantly associated with increased odds of metabolic syndrome. Each unit increase in MDS was associated with approximately a 30% higher risk for metabolic syndrome, even after adjusting for confounding factors (OR 1.31; 95% CI 1.17-1.45). Restricted cubic spline graphs depicted a linear dose-response relationship across the MDS range. This positive correlation remained consistent across various population subgroups and exhibited no significant interaction by age, gender, race, adiposity, smoking status, or alcohol consumption. CONCLUSIONS: Higher urinary magnesium loss as quantified by MDS may be an independent linear risk factor for metabolic syndrome in US adults, irrespective of sociodemographic and behavioral factors. Optimizing magnesium nutritional status could potentially confer benefits to patients with metabolic syndrome.

13.
Adv Healthc Mater ; 13(11): e2303856, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38221719

RESUMO

Porphyrin photosensitizers are the classic drugs in clinical photodynamic therapy (PDT), but the hypoxia of tumor environment and the rapid oxygen consumption of PDT severely weaken their therapeutic effect. A recently reported water-dependent reversible photoacidity therapy (W-RPAT) is O2-independence, providing a solution for the treatment of hypoxic tumors. In this work, TPP-O-PEG5, a porphyrin derivative with binary properties of PDT and W-RPAT, is designed and synthesized for the first time. The nanoparticles (NPs) of TPP-O-PEG5 encapsulated with DSPE-mPEG2000, an amphiphilic polymer approved by Food and Drug Administration, can simultaneously produce reactive oxygen species and H+ under irradiation of a 660 nm laser, and revert the H+ back under darkness, presenting strong phototoxicity to multiple tumor cell lines with no obvious difference between the IC50 values tested under normoxic (≈20% O2) and hypoxic (<0.5% O2) conditions. Excitingly, in vivo experiments show that the therapeutic effect of TPP-O-PEG5 NPs on large hypoxic tumors is better than that of NPe6, a clinical porphin PDT drug. This work provides a novel strategy for porphyrin photosensitizers to break through the limitation of hypoxic environment, and significantly improve the phototherapeutic effect on hypoxic tumors.


Assuntos
Fotoquimioterapia , Fármacos Fotossensibilizantes , Porfirinas , Fotoquimioterapia/métodos , Porfirinas/química , Porfirinas/farmacologia , Humanos , Animais , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Camundongos , Linhagem Celular Tumoral , Água/química , Nanopartículas/química , Espécies Reativas de Oxigênio/metabolismo , Camundongos Endogâmicos BALB C , Hipóxia Tumoral/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Neoplasias/terapia , Polietilenoglicóis/química , Camundongos Nus
14.
Age Ageing ; 53(1)2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38251736

RESUMO

BACKGROUND: Fragmentation of services increases health and social care burden as people live longer with higher prevalence of diseases, frailty and dependency. Local evidence for implementing person-centred integrated care is urgently needed to advance practice and policies to achieve healthy ageing. OBJECTIVE: To test the feasibility and impact of World Health Organization's (WHO) Integrated Care for Older People (ICOPE) approach in China. DESIGN: A randomised controlled trial examining the feasibility of implementing ICOPE approach, evaluating its impact on health outcomes and health resource utilisation. SETTING: Primary care setting in urban and suburban communities of Chaoyang District, Beijing, China. SUBJECTS: Community-dwelling older adults screened as at-risk of functional declines and randomised into intervention (537) and control (1611) groups between September 2020 and February 2021. METHODS: A 6-month intervention program following WHO's ICOPE care pathways implemented by integrated care managers compared to standard available care. RESULTS: After 1 to 1 propensity score matching, participants in intervention and control groups (totally 938) had comparable baseline characteristics, demonstrated feasibility of implementing ICOPE with satisfaction by participants (97-99%) and providers (92-93%). All outcomes showed improvements after a 6-month intervention, while statistically significant least-squares mean differences (control-intervention) in vitality (Mini-Nutritional Assessment Short Form to measure vitality, -0.21, 95% CI, -0.40-0.02), mobility (Short Physical Performance Battery to measure mobility, -0.29, 95% CI, -0.44-0.14) and psychological health (Geriatric Depression Scale five items to measure psychological health, 0.09, 95% CI, 0.03-0.14) were observed (P < 0.05). CONCLUSIONS: It is feasible to localise and implement WHO's ICOPE approach in regions with fragmented resources such as China. Preliminary evidence supports its acceptance among key stakeholders and impact on health outcomes.


Assuntos
Sobrecarga do Cuidador , Prestação Integrada de Cuidados de Saúde , Humanos , Idoso , China/epidemiologia , Organização Mundial da Saúde , Procedimentos Clínicos
15.
Light Sci Appl ; 13(1): 25, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38253520

RESUMO

Classical and quantum space-to-ground communications necessitate highly sensitive receivers capable of extracting information from modulated photons to extend the communication distance from near-earth orbits to deep space explorations. To achieve gigabit data rates while mitigating strong background noise photons and beam drift in a highly attenuated free-space channel, a comprehensive design of a multi-functional detector is indispensable. In this study, we present an innovative compact multi-pixel superconducting nanowire single-photon detector array that integrates near-unity detection efficiency (91.6%), high photon counting rate (1.61 Gcps), large dynamic range for resolving different photon numbers (1-24), and four-quadrant position sensing function all within one device. Furthermore, we have constructed a communication testbed to validate the advantages offered by such an architecture. Through 8-PPM (pulse position modulation) format communication experiments, we have achieved an impressive maximum data rate of 1.5 Gbps, demonstrating sensitivities surpassing previous benchmarks at respective speeds. By incorporating photon number information into error correction codes, the receiver can tolerate maximum background noise levels equivalent to 0.8 photons/slot at a data rate of 120 Mbps-showcasing a great potential for daylight operation scenarios. Additionally, preliminary beam tracking tests were conducted through open-loop scanning techniques, which revealed clear quantitative dependence indicating sensitivity variations based on beam location. Based on the device characterizations and communication results, we anticipate that this device architecture, along with its corresponding signal processing and coding techniques, will be applicable in future space-to-ground communication tasks.

16.
Int J Pharm ; 652: 123810, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38244648

RESUMO

Transforming growth factor ß (TGF-ß), a versatile immunosuppressive cytokine, has gained increasing attention as a potential target for cancer immunotherapy. However, current strategies are constrained by tumor heterogeneity and drug resistance. Therapeutic probiotics, such as Escherichia coli Nissle1917 (EcN), not only regulate the gut microbiota to increase beneficial bacteria with anti-tumor effects, but also modulate immune factors within the body, thereby enhancing immunity. In this study, we developed an oral microgel delivery system of EcN@(CS-SA)2 by electrostatic interaction between chitosan (CS) and sodium alginate (SA), aiming to enhance its bioavailability in the gastrointestinal tract (GIT). Notably, EcN@(CS-SA)2 microgel showed a synergistic enhancement of the anti-tumor efficacy of Galunisertib (Gal, a TGF-ß inhibitor) by inducing apoptosis and immunogenic cell death (ICD) in tumor cells, as well as promoting increased infiltration of CD8+ T cells into the tumor microenvironment (TME).


Assuntos
Neoplasias Colorretais , Microgéis , Probióticos , Pirazóis , Quinolinas , Humanos , Fator de Crescimento Transformador beta/metabolismo , Linfócitos T CD8-Positivos , Imunoterapia , Neoplasias Colorretais/tratamento farmacológico , Imunidade , Microambiente Tumoral , Linhagem Celular Tumoral
17.
Mol Microbiol ; 121(1): 129-141, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38082493

RESUMO

Brucella abortus is a facultative, intracellular, zoonotic pathogen that resides inside macrophages during infection. This is a specialized niche where B. abortus encounters various stresses as it navigates through the macrophage. In order to survive this harsh environment, B. abortus utilizes post-transcriptional regulation of gene expression through the use of small regulatory RNAs (sRNAs). Here, we characterize a Brucella sRNAs called MavR (for MurF- and virulence-regulating sRNA), and we demonstrate that MavR is required for the full virulence of B. abortus in macrophages and in a mouse model of chronic infection. Transcriptomic and proteomic studies revealed that a major regulatory target of MavR is MurF. MurF is an essential protein that catalyzes the final cytoplasmic step in peptidoglycan (PG) synthesis; however, we did not detect any differences in the amount or chemical composition of PG in the ΔmavR mutant. A 6-nucleotide regulatory seed region within MavR was identified, and mutation of this seed region resulted in dysregulation of MurF production, as well as significant attenuation of infection in a mouse model. Overall, the present study underscores the importance of sRNA regulation in the physiology and virulence of Brucella.


Assuntos
Brucelose , Pequeno RNA não Traduzido , Animais , Camundongos , Brucella abortus/metabolismo , Regulação da Expressão Gênica , Macrófagos , Camundongos Endogâmicos BALB C , Proteômica , Pequeno RNA não Traduzido/genética , Pequeno RNA não Traduzido/metabolismo
18.
Adv Sci (Weinh) ; 11(5): e2302875, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38039443

RESUMO

Photoacid generators (PAGs) are compounds capable of producing hydrogen protons (H+ ) upon irradiation, including irreversible and reversible PAGs, which have been widely studied in photoinduced polymerization and degradation for a long time. In recent years, the applications of PAGs in the biomedical field have attracted more attention due to their promising clinical value. So, an increasing number of novel PAGs have been reported. In this review, the recent progresses of PAGs for biomedical applications is systematically summarized, including tumor treatment, antibacterial treatment, regulation of protein folding and unfolding, control of drug release and so on. Furthermore, a concept of water-dependent reversible photoacid (W-RPA) and its antitumor effect are highlighted. Eventually, the challenges of PAGs for clinical applications are discussed.

19.
ChemSusChem ; 17(7): e202301622, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38100189

RESUMO

Direct borohydride fuel cells (DBFCs) convert borohydride (NaBH4) chemical energy into clean electricity. However, catalytic active site deactivation in NaBH4 solution limits their performance and stability. We propose a strategy to regulate active sites in Co-based catalysts using polypyrrole modification (Co-PX catalyst) to enhance electrochemical borohydride oxidation reaction (eBOR). As an anode catalyst, the synthesized Co-PX catalyst exhibits excellent eBOR performance in DBFCs, with current density of 280 mA ⋅ cm-2 and power density of 151 mW ⋅ cm-2, nearly twice that of the unmodified catalyst. The Co-PX catalyst shows no degradation after 120-hour operation, unlike the rapidly degrading control. In-situ electrochemical attenuated total reflection Fourier-transform infrared spectroscopy (ATR-FTIRS) and density functional theory (DFT) suggest that polypyrrole-modified carbon support regulate the charge distribution, increasing oxidation state and optimizing adsorption/desorption of intermediates. A possible reaction pathway is proposed. This work presents a promising strategy for efficient polymer-modulated catalysts in advanced DBFCs.

20.
Natl Sci Rev ; 11(1): nwad102, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38116087

RESUMO

Precisely acquiring the timing information of individual X-ray photons is important in both fundamental research and practical applications. The timing precision of commonly used X-ray single-photon detectors remains in the range of one hundred picoseconds to microseconds. In this work, we report on high-timing-precision detection of single X-ray photons through the fast transition to the normal state from the superconductive state of superconducting nanowires. We successfully demonstrate a free-running X-ray single-photon detector with a timing resolution of 20.1 ps made of 100-nm-thick niobium nitride film with an active area of 50 µm by 50 µm. By using a repeated differential timing measurement on two adjacent X-ray single-photon detectors, we demonstrate a precision of 0.87 ps in the arrival-time difference of X-ray photon measurements. Therefore, our work significantly enhances the timing precision in X-ray photon counting, opening a new niche for ultrafast X-ray photonics and many associated applications.

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