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1.
J Hepatol ; 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38992769

RESUMO

BACKGROUND & AIMS: The changes of HBV-specific B-cells in chronic hepatitis B (CHB) patients underwent pegylated interferon-alfa (PEG-IFNα) treatment and achieved functional cure remain unclear. We aimed to evaluate the alterations in HBV-specific B-cells during treatment and therefore explored the mechanism of functional recovery of HBsAg-specific B-cells. METHODS: We included 39 nucleos(t)ide analogues-treated CHB patients who received sequential combination therapy with PEG-IFNα and 8 treatment-naive CHB patients. HBV-specific B-cells were characterized ex vivo using fluorescent labeled HBsAg and HBcAg. The frequency, phenotype, and subsets of HBV-specific B-cells and follicular helper T cells (Tfh-cells) were detected using flow cytometry. The functionality of HBV-specific B-cells was quantified through ELISpot assays. RESULTS: During treatment, the fraction of activated memory B-cells (MBCs) among HBsAg-specific B-cells and the expression of IgG, CXCR3, and CD38 increased. Antibody-secretion capacity of HBsAg-specific B-cell was restored after treatment only in patients with a functional cure and it showed a positive correlation with serum hepatitis B surface antibody levels. The phenotype and function of HBsAg-specific B-cells differed between patients with and without functional cure. Patients with functional cure exhibited IgG+ classical MBCs and plasmablasts in HBsAg-specific B-cells. HBcAg-specific B-cells displayed both attenuated antibody secretion with reduced IgG expression and an IgM+ atypical type of MBCs after treatment, irrespective of with and without functional cure. The number of CD40L+ Tfh-cells increased after PEG-IFNα treatment and positively correlated with HBsAg-specific B-cell activation. CONCLUSIONS: After PEG-IFNα treatment, HBsAg- and HBcAg-specific B-cells exhibit various changes in antibody secretion. Their functional differences are reflected in the alterations in phenotypes and subtypes. The presence of CD40L+ Tfh-cells is associated with the active recovery of HBsAg-specific B-cells. IMPACT AND IMPLICATIONS: HBV-related complications and hepatocellular carcinoma remain the leading causes of mortality from chronic liver disease worldwide, and a cure is rarely achieved with antiviral therapies. Elucidating the immunological mechanisms underlying the functional cure of CHB patients offers a promising therapeutic strategy for viral clearance, such as therapeutic vaccine. We analyzed the alterations in HBV-specific B-cells in patients treated with PEG-IFNα and identified novel pathways for immunotherapeutic boosting of B cell immunity.

2.
J Zhejiang Univ Sci B ; : 1-16, 2024 Jul 09.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-38993075

RESUMO

Grooming, as an evolutionarily conserved repetitive behavior, is common in various animals, including humans, and serves essential functions including, but not limited to, hygiene maintenance, thermoregulation, de-arousal, stress reduction, and social behaviors. In rodents, grooming involves a patterned and sequenced structure, known as the syntactic chain with four phases that comprise repeated stereotyped movements happening in a cephalocaudal progression style, beginning from the nose to the face, to the head, and finally ending with body licking. The context-dependent occurrence of grooming behavior indicates its adaptive significance. This review briefly summarizes the neural substrates responsible for rodent grooming behavior and explores its relevance in rodent models of neuropsychiatric disorders and neurodegenerative diseases with aberrant grooming phenotypes. We further emphasize the utility of rodent grooming as a reliable measure of repetitive behavior in neuropsychiatric models, holding promise for translational psychiatry. Herein, we mainly focus on rodent self-grooming. Allogrooming (grooming being applied on one animal by its conspecifics via licking or carefully nibbling) and heterogrooming (a form of grooming behavior directing towards another animal, which occurs in other contexts, such as maternal, sexual, aggressive, or social behaviors) are not covered due to space constraints.

3.
Neural Regen Res ; 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38993127

RESUMO

ABSTRACT: Parkinson's disease is the second most common progressive neurodegenerative disorder, and few reliable biomarkers are available to track disease progression. The proteins, DNA, mRNA, and lipids carried by exosomes reflect intracellular changes, and thus can serve as biomarkers for a variety of conditions. In this study, we investigated alterations in the protein content of plasma exosomes derived from patients with Parkinson's disease and the potential therapeutic roles of these proteins in Parkinson's disease. Using a tandem mass tag-based quantitative proteomics approach, we characterized the proteomes of plasma exosomes derived from individual patients, identified exosomal protein signatures specific to patients with Parkinson's disease, and identified N-acetyl-alpha-glucosaminidase as a differentially expressed protein. N-acetyl-alpha-glucosaminidase expression levels in exosomes from the plasma of patients and healthy controls were validated by enzyme-linked immunosorbent assay and western blot. The results demonstrated that the exosomal N-acetyl-alpha-glucosaminidase concentration was not only lower in Parkinson's disease, but also decreased with increasing Hoehn-Yahr stage, suggesting that N-acetyl- alpha-glucosaminidase could be used to rapidly evaluate Parkinson's disease severity. Furthermore, western blot and immunohistochemistry analysis showed that N-acetyl-alpha-glucosaminidase levels were markedly reduced both in cells treated with methyl-4-phenylpyridinium (MPP+) and cells overexpressing a-synuclein (α-syn) compared with control cells. Additionally, N-acetyl-alpha-glucosaminidase overexpression significantly increased cell viability and inhibited α-syn expression in MPP+-treated cells. Taken together, our findings demonstrate for the first time that exosomal N-acetyl-alpha-glucosaminidase may serve as a biomarker for Parkinson's disease diagnosis, and that N-acetyl-alpha- glucosaminidase may reduce α-syn expression and MPP+-induced neurotoxicity, thus providing a new therapeutic target for Parkinson's disease.

4.
World J Oncol ; 15(4): 579-591, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38993248

RESUMO

Background: Lymph node status is a prominent prognostic factor for intrahepatic cholangiocarcinoma (ICC). However, the prognostic value of performing lymph node dissection (LND) in patients with clinical node-negative ICC remains controversial. The aim of this study was to evaluate the clinical value of LND on long-term outcomes in this subgroup of patients. Methods: We retrospectively analyzed patients who underwent radical liver resection for clinically node-negative ICC from three tertiary hepatobiliary centers. The propensity score matching analysis at 1:1 ratio based on clinicopathological data was conducted between patients with and without LND. Recurrence-free survival (RFS) and overall survival (OS) were compared in the matched cohort. Results: Among 303 patients who underwent radical liver resection for ICC, 48 patients with clinically positive nodes were excluded, and a total of 159 clinically node-negative ICC patients were finally eligible for the study, with 102 in the LND group and 57 in the non-LND group. After propensity score matching, two well-balanced groups of 51 patients each were analyzed. No significant difference of median RFS (12.0 vs. 10.0 months, P = 0.37) and median OS (22.0 vs. 26.0 months, P = 0.47) was observed between the LND and non-LND group. Also, LND was not identified as one of the independent risks for survival. Among 51 patients who received LND, 11 patients were with positive lymph nodes (lymph node metastasis (LNM) (+)) and presented significantly worse outcomes than those with LND (-). On the other hand, postoperative adjuvant therapy was the independent risk factor for both RFS (hazard ratio (HR): 0.623, 95% confidence interval (CI): 0.393 - 0.987, P = 0.044) and OS (HR: 0.585, 95% CI: 0.359 - 0.952, P = 0.031). Furthermore, postoperative adjuvant therapy was associated with prolonged survivals of non-LND patients (P = 0.02 for RFS and P = 0.03 for OS). Conclusions: Based on the data, we found that LND did not significantly improve the prognosis of patients with clinically node-negative ICC. Postoperative adjuvant therapy was associated with prolonged survival of ICC patients, especially in non-LND individuals.

5.
Phytomedicine ; 132: 155849, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38964152

RESUMO

BACKGROUND: With the increasing awareness of the safety of traditional Chinese medicine and food, as well as in-depth studies on the pharmacological activity and toxicity of Zanthoxylum armatum DC. (ZADC), it has been found that ZADC is hepatotoxic. However, the toxic substance basis and mechanism of action have not been fully elucidated. Hydroxy-α-sanshool (HAS) belongs to an amide compound in the fruits of ZADC, which may be hepatotoxic. However, the specific effects of HAS, including liver toxicity, are unclear. PURPOSE: The objectives of this research was to determine how HAS affects hepatic lipid metabolism, identify the mechanism underlying the accumulation of liver lipids by HAS, and offer assurances on the safe administration of HAS. METHODS: An in vivo experiment was performed by gavaging C57 BL/6 J mice with various dosages of HAS (5, 10, and 20 mg/kg). Biochemical indexes were measured, and histological analysis was performed to evaluate HAS hepatotoxicity. Hepatic lipid levels were determined using lipid indices and oil red O (ORO) staining. Intracellular lipid content were determined by biochemical analyses and ORO staining after treating HepG2 cells with different concentrations of HAS in vitro. Mitochondrial membrane potential, respiratory chain complex enzymes, and ATP levels were assessed by fluorescence labeling of mitochondria. The levels of proteins involved in lipogenesis and catabolism were determined using Western blotting. RESULTS: Mice in the HAS group had elevated alanine and aspartate aminotransferase blood levels as well as increased liver index compared with the controls. The pathological findings showed hepatocellular necrosis. Serum and liver levels of triglycerides, total cholesterol, and low-density lipoprotein cholesterol levels were increased, whereas high-density lipoprotein cholesterol levels decreased. The ORO staining findings demonstrated elevated liver lipid levels. In vitro experiments demonstrated a notable elevation in triglyceride and total cholesterol levels in the HAS group. ATP, respiratory chain complex enzyme gene expression, mitochondrial membrane potential, and mitochondrial number were reduced in the HAS group. The levels of lipid synthesis-associated proteins (ACC, FASN, and SREBP-1c) were increased, and lipid catabolism-associated protein levels (PPARα and CPT1) and the p-AMPK/AMPK ratio were decreased in vivo and in vitro. CONCLUSION: HAS has hepatotoxic effects, which can induce fatty acid synthesis and mitochondrial function damage by inhibiting the AMPK signaling pathway, resulting in aberrant lipid increases.

6.
Asia Pac J Clin Nutr ; 33(3): 447-456, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38965732

RESUMO

BACKGROUND AND OBJECTIVES: Frailty has become a public health challenge in China. To investigate the association of foods consumption and physical activity with prefrailty and frailty among older Chinese adults in urban communities. METHODS AND STUDY DESIGN: In a cross-sectional study from February to July 2023, 1183 older adults aged between 65y-88y were enrolled from urban communities in Chongqing and Shandong province, China. Frailty Index (FI) was applied to measure prefrailty and frailty. Partial proportional odds model was used to assess the association between foods consumption, physical activity and prefrailty/frailty. RESULTS: Higher Dietary Diversity Score (DDS), (OR=0.61, 95% CI=0.46-0.80; OR=0.47, 95% CI=0.28-0.79), Consuming animal-based foods ≥2 times/day (OR=0.62, 95% CI=0.47-0.82; OR=0.54, 95% CI=0.33-0.88), soy products ≥2 times/week (OR=0.69, 95% CI=0.53-0.89; OR=0.51, 95% CI=0.31-0.84), fresh vegetables ≥2 times/day (OR=0.42, 95% CI=0.31-0.57; OR=0.41, 95% CI=0.23-0.72), and nuts ≥2 times/week (OR=0.71, 95% CI=0.55-0.91; OR=0.52, 95% CI=0.32-0.85) was associated with a lower risk of prefrailty and frailty. In addition, higher frequency and longer duration of walking (OR=0.61, 95% CI=0.42-0.88; OR=0.63, 95% CI=0.48-0.81), exercise (OR=0.48, 95% CI=0.35-0.64; OR=0.44, 95% CI=0.32-0.61) per week were significantly associated with lower risk of prefrailty. Furthermore, higher frequency and longer duration of walking (OR=0.42, 95% CI=0.25-0.72; OR=0.46, 95% CI=0.29-0.74), and housework (OR=0.39, 95% CI=0.24-0.65; OR=0.57, 95% CI=0.34-0.96) per week, were significantly associated with lower frailty. CONCLUSIONS: Higher DDS and higher frequency of animal-based foods, soy products, fresh vegetables, and nuts consumption is significantly associated with lower risk of prefrailty and frailty. Additionally, walking and exercising are significantly associated with lower risk of prefrailty, while walking and doing housework is significantly associated with lower frailty.


Assuntos
Dieta , Exercício Físico , Fragilidade , População Urbana , Humanos , Idoso , Estudos Transversais , Masculino , Feminino , China/epidemiologia , Fragilidade/epidemiologia , Idoso de 80 Anos ou mais , População Urbana/estatística & dados numéricos , Dieta/estatística & dados numéricos , Dieta/métodos , Idoso Fragilizado/estatística & dados numéricos , População do Leste Asiático
7.
Plant Cell Environ ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38965879

RESUMO

Thrips, Frankliniella intonsa, is a highly polyphagous pest with a worldwide distribution. F. intonsa-infested sunflower seeds show marked visual damage. The study findings revealed that significantly more F. intonsa infested confection sunflower compared to oilseed sunflower, via olfactometer bioassay studies, we found that compared with the flower and pollen of oilseed sunflowers, those of confection sunflowers attract F. intonsa. Considering this discrepancy in the preference of F. intonsa on oilseed and confection sunflowers, the volatiles of the flower and pollens of two sunflowers were analysed by gas chromatography-mass spectroscopy. The behavioural responses of F. intonsa were assessed for these compounds using Y-tube bioassays. Geranyl bromide, a unique volatile component of oilseed sunflowers, induced an assertive approach-avoidance behaviour in F. intonsa, whereas the unique component ethyl isovalerate in confection sunflowers attracted F. intonsa. F. intonsa adults demonstrated significant attraction to the blends of confection sunflowers. Furthermore, field verification revealed that intercropping confection and oilseed sunflowers could effectively control F. intonsa. The study provided insights into the chemical cues used by F. intonsa in locating hosts. Therefore, oilseed sunflowers can be used as repellent plants to prevent F. intonsa invasion.

8.
Ultrason Sonochem ; 108: 106979, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38972094

RESUMO

To investigate the effect of ultrasound treatment on the flavor profile of beef during postmortem aging, a comprehensive analysis of beef flavor was conducted at 0, 7, and 12 d of aging using sensory evaluation and electronic nose. Furthermore, the key volatile flavor compounds were identified using gas chromatography-mass spectrometry (GC-MS), and the odor activity value (OAV) was further evaluated. In addition, the primary pathway involved in flavor formation during beef aging after ultrasound treatment was explored. The results indicated that ultrasound enhanced the flavor profile of beef during postmortem aging by modifying the OAV of hexanal, heptanal, octanal, nonanal, decanal, (Z)-2-nonenal, dodecanal, pentanal, 1-octen-3-ol, octanoic acid, and 2-pentylfuran. Lipid oxidation was a crucial pathway through which ultrasound promoted the generation of volatile flavor compounds in beef, confirmed by the improved oxidation level of fatty acids, particularly monounsaturated ones. The study indicates that ultrasound technology can be regarded as an effective method for enhancing the beef flavor profile during postmortem aging.

9.
Biomed Pharmacother ; 177: 117085, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38972150

RESUMO

Accumulating evidence strongly support the key role of NLRP3-mediated pyroptosis in the pathogenesis and progression of vascular endothelial dysfunction associated with diabetes mellitus. Various studies have demonstrated that the activation or upregulation of Silent Information Regulation 2 homolog 2 (SIRT2) exerts inhibitory effect on the expression of NLRP3. Although 1,8-cineole has been found to protect against endothelial dysfunction and cardiovascular diseases, its role and mechanism in diabetic angiopathy remain unknown. Therefore, the aim of this study was to investigate the ameliorative effect of 1,8-cineole through SIRT2 on pyroptosis associated with diabetic angiopathy in human umbilical vein endothelial cells (HUVECs) and to elucidate the underlying mechanism. The findings revealed that 1,8-cineole exhibited a protective effect against vascular injury and ameliorated pathological alterations in the thoracic aorta of diabetic mice. Moreover, it effectively mitigated pyroptosis induced by palmitic acid-high glucose (PA-HG) in HUVECs. Treatment with 1,8-cineole effectively restored the reduced levels of SIRT2 and suppressed the elevated expression of pyroptosis-associated proteins. Additionally, our findings demonstrated the occurrence of NLRP3 deacetylation and the physical interaction between NLRP3 and SIRT2. The SIRT2 inhibitor AGK2 and siRNA-SIRT2 effectively attenuated the effect of 1,8-cineole on NLRP3 deacetylation in HUVECs and compromised its inhibitory effect against pyroptosis in HUVECs. However, overexpression of SIRT2 inhibited PA-HG-induced pyroptosis in HUVECs. 1,8-Cineole inhibited the deacetylation of NLRP3 by regulating SIRT2, thereby reducing pyroptosis in HUVECs. In conclusion, our findings suggest that PA-HG-induced pyroptosis in HUVECs plays a crucial role in the development of diabetic angiopathy, which can be mitigated by 1,8-cineole.

10.
Adv Sci (Weinh) ; : e2401855, 2024 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-38973158

RESUMO

Clinically, chronic pain and depression often coexist in multiple diseases and reciprocally reinforce each other, which greatly escalates the difficulty of treatment. The neural circuit mechanism underlying the chronic pain/depression comorbidity remains unclear. The present study reports that two distinct subregions in the paraventricular thalamus (PVT) play different roles in this pathological process. In the first subregion PVT posterior (PVP), glutamatergic neurons (PVPGlu) send signals to GABAergic neurons (VLPAGGABA) in the ventrolateral periaqueductal gray (VLPAG), which mediates painful behavior in comorbidity. Meanwhile, in another subregion PVT anterior (PVA), glutamatergic neurons (PVAGlu) send signals to the nucleus accumbens D1-positive neurons and D2-positive neurons (NAcD1→D2), which is involved in depression-like behavior in comorbidity. This study demonstrates that the distinct thalamo-subcortical circuits PVPGlu→VLPAGGABA and PVAGlu→NAcD1→D2 mediated painful behavior and depression-like behavior following spared nerve injury (SNI), respectively, which provides the circuit-based potential targets for preventing and treating comorbidity.

11.
Int J Biol Macromol ; 275(Pt 1): 133643, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38964680

RESUMO

In this study, the effects of different ultrasonic treatment intensities (57, 170, and 283 W/cm2) on the chemical composition, molecular chain characteristics, crystal structure, micromorphology, interfacial adsorption behavior and emulsifying properties of sugar beet pectin (SBP) were investigated. Ultrasonic treatment did not change the types of SBP monosaccharides, but it had impacts on their various monosaccharide contents. Moreover, the feruloylated, acetyl, and methoxy groups of SBP also undergo varying degrees of changes. The increase in ultrasonic treatment intensity led to transition in the molecular chain conformation of SBP from rigid semi-flexible chains to flexible chains, accompanied by modification in its crystal structure. Microstructural analysis of SBP confirmed the significant change in molecular chain conformation. Modified SBP could form an elastic interfacial film with higher deformation resistance on the oil-water interface. The SBP sample modified with 170 W/cm2 exhibited better emulsifying properties owing to its better interfacial adsorption behavior. Moreover, the emulsions prepared with modified SBP exhibited better stability capability under different environmental stresses (pH value, salt ion concentration, heating temperature and freeze-thaw treatment). The results revealed that the ultrasonic technology is useful to improve the emulsifying properties of SBP.

12.
J Phys Chem A ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38968614

RESUMO

A series of anionic transition metal halides, OsCln- (n = 3-5), have been investigated using a newly developed, home-constructed, cryogenic anion cluster photoelectron spectroscopy. The target anionic species are generated through collision-induced dissociation in a two-stage ion funnel. The measured vertical detachment energies (VDEs) are 3.48, 4.54, and 4.81 eV for n = 3, 4, and 5, respectively. Density functional theory calculations at the B3LYP-D3(BJ)//aug-cc-pVTZ(-pp) level predict the lowest energy structures of the atomic form of OsCln- (n = 3-5) to be a quintet triangle, quartet square, and quintet square-based pyramid, respectively. The CCSD(T)-calculated VDEs and corresponding adiabatic detachment energies agree well with our experimental measurements. Analysis of the corresponding frontier molecular orbitals and charge density differences suggests that the d-orbitals of the transition metal Os play a primary role in the single-photon detachment processes, and the detached electrons originating from different molecular orbitals are distinguishable.

13.
ACS Nano ; 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38950189

RESUMO

Liposomes are versatile drug delivery systems in clinical use for cancer and many other diseases. Unfortunately, PEGylated liposomal doxorubicin (sLip/DOX) exhibits serious dose-limiting cutaneous toxicities, which are closely related to the extravascular accumulation of sLip/DOX in the dermis. No clinical interventions have been proposed for cutaneous toxicities due to the elusive transport pathways. Herein, we showed that the reciprocal interaction between liposomes and neutrophils played pivotal roles in liposome extravasation into the dermis. Neutrophils captured liposomes via the complement receptor 3 (CD11b/CD18) recognizing the fragment of complement component C3 (iC3b) deposited on the liposomal surface. Uptake of liposomes also activated neutrophils to induce CD11b upregulation and enhanced the ability of neutrophils to migrate outside the capillaries. Furthermore, inhibition of complement activation either by CRIg-L-FH (a C3b/iC3b targeted complement inhibitor) or blocking the phosphate negative charge in mPEG-DSPE could significantly reduce liposome uptake by neutrophils and alleviate the cutaneous accumulation of liposomes. These results validated the liposome extravasation pathway mediated by neutrophils and provided potential solutions to the devastating cutaneous toxicities occurring during sLip/DOX treatment.

14.
Chem Commun (Camb) ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38952177

RESUMO

Presented herein is a series of chain compounds based on pre-designed heterometallic aluminum-lanthanide (Al-Ln) Al4Ln4 molecular rings. Their photoluminescence quantum yield (PLQY) with Eu3+ (30.41%) and Tb3+ (41.44%) is at a high level among the clusters containing four Ln ions. This study significantly extends the family of Al-Ln heterometallic clusters and demonstrates the synergistic effect of heterometallic ions in enhancing their properties.

15.
Inorg Chem ; 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38984385

RESUMO

Efficient CO oxidation at ambient or low temperatures is essential for environmental purification and selective CO oxidation in H2, yet achieving this remains a challenge with current methodologies. In this research, we extensively evaluated the catalytic performance of phosphotungstic acid (PTA)-supported 11 M1/PTA single-atom catalysts (SACs) using density functional theory calculations across both gas phase and 12 common solvents. The Rh1/PTA, Pd1/PTA, and Pt1/PTA systems exhibit moderate CO adsorption energies, facilitating the feasibility of oxygen vacancy formation. Remarkably, the Pd1/PTA and Pt1/PTA catalysts exhibited negligible energy barriers and demonstrated exceptionally high catalytic rates, with values reaching up to (1 × 1010)11, markedly exceeding the threshold for room temperature reactions, set at 6.55 × 108. This phenomenon is attributed to a transition from the high-energy barrier processes of oxygen dissociation in O2 and N-O bond dissociation in N2O to the more efficient dissociation of H2O2. Orbital analysis and charge variations at metal sites throughout the reaction process provide deeper insights into the role of the three metal catalytic sites in CO activation. Our findings not only reveal key aspects of SACs in facilitating CO oxidation at low temperatures but also provide valuable insights for future catalytic reaction mechanism studies and environmental applications.

16.
Angew Chem Int Ed Engl ; : e202411576, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38984566

RESUMO

Mechanically interlocked molecules, such as rotaxanes, have drawn significant attention within supramolecular chemistry. Although a variety of macrocycles have been thoroughly explored in rotaxane synthesis, metal-organic macrocycles remain relatively under-investigated. Aluminum molecular rings, with their inner cavities and numerous binding sites, present a promising option for constructing rotaxanes. Here, we introduce an innovative "ring-donor···axle-acceptor" motif utilizing Al8 molecular rings, enabling the stepwise assembly of molecules, complexes, and polymers through tailored coordination chemistry. This novel approach can not only be applied to macrocycle-based systems like catenanes but also enhance specific functionalities progressively.

17.
Nano Lett ; 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38984749

RESUMO

The synthesis of transition metal nitrides nanocrystals (TMNs NCs) has posed a significant challenge due to the limited reactivity of nitrogen sources at lower temperatures and the scarcity of available synthesis methods. In this study, we present a novel colloidal synthesis strategy for the fabrication of Cu3N nanorods (NRs). It is found that the trace oxygen (O2) plays an important role in the synthesis process. And a new mechanism for the formation of Cu3N is proposed. Subsequently, by employing secondary lateral epitaxial growth, the Cu3N-Cu2O heteronanostructures (HNs) can be prepared. The Cu3N NRs and Cu3N-Cu2O HNs were evaluated as precursor electrocatalysts for the CO2 reduction reaction (CO2RR). The Cu3N-Cu2O HNs demonstrate remarkable selectivity and stability with ethylene (C2H4) Faradaic efficiency (FE) up to 55.3%, surpassing that of Cu3N NRs. This study provides innovative insights into the reaction mechanism of colloidal synthesis of TMNs NCs and presents alternative options for designing cost-effective electrocatalysts to achieve carbon neutrality.

18.
Appl Environ Microbiol ; : e0055724, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953658

RESUMO

Klebsiella pneumoniae can enter a viable but nonculturable (VBNC) state to survive in unfavorable environments. Our research found that high-, medium-, and low-alcohol-producing K. pneumoniae strains are associated with nonalcoholic fatty liver disease. However, the presence of the three Kpn strains has not been reported in the VBNC state or during resuscitation. In this study, the effects of different strains, salt concentrations, oxygen concentrations, temperatures, and nutrients in K. pneumoniae VBNC state were evaluated. The results showed that high-alcohol-producing K. pneumoniae induced a slower VBNC state than medium-alcohol-producing K. pneumoniae, and low-alcohol-producing K. pneumoniae. A high-salt concentration and micro-oxygen environment accelerated the loss of culturability. Simultaneously, both real-time quantitative PCR and droplet digital PCR were developed to compare the quantitative comparison of three Kpn strain VBNC states by counting single-copy gene numbers. At 22°C or 37°C, the number of culturable cells decreased significantly from about 108 to 105-106 CFU/mL. In addition, imipenem, ciprofloxacin, polymyxin, and phiW14 inhibited cell resuscitation but could not kill VBNC-state cells. These results revealed that the different environments evaluated play different roles in the VBNC induction process, and new effective strategies for eliminating VBNC-state cells need to be further studied. These findings provide a better understanding of VBNC-state occurrence, maintenance, detection, and absolute quantification, as well as metabolic studies of resuscitation resistance and ethanol production.IMPORTANCEBacteria may enter VBNC state under different harsh environments. Pathogenic VBNC bacteria cells in clinical and environmental samples pose a potential threat to public health because cells cannot be found by routine culture. The alcohol-producing Kpn VBNC state was not reported, and the influencing factors were unknown. The formation and recovery of VBNC state is a complete bacterial escape process. We evaluated the influence of multiple induction conditions on the formation of VBNC state and recovery from antibiotic and bacteriophage inhibition, and established a sensitive molecular method to enumerate the VBNC cells single-copy gene. The method can improve the sensitivity of pathogen detection in clinical, food, and environmental contamination monitoring, and outbreak warning. The study of the formation and recovery of VBNC-state cells under different stress environments will also promote the microbiological research on the development, adaptation, and resuscitation in VBNC-state ecology.

19.
Med Image Anal ; 97: 103251, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38954942

RESUMO

Accurate histopathological subtype prediction is clinically significant for cancer diagnosis and tumor microenvironment analysis. However, achieving accurate histopathological subtype prediction is a challenging task due to (1) instance-level discrimination of histopathological images, (2) low inter-class and large intra-class variances among histopathological images in their shape and chromatin texture, and (3) heterogeneous feature distribution over different images. In this paper, we formulate subtype prediction as fine-grained representation learning and propose a novel multi-instance selective transformer (MIST) framework, effectively achieving accurate histopathological subtype prediction. The proposed MIST designs an effective selective self-attention mechanism with multi-instance learning (MIL) and vision transformer (ViT) to adaptive identify informative instances for fine-grained representation. Innovatively, the MIST entrusts each instance with different contributions to the bag representation based on its interactions with instances and bags. Specifically, a SiT module with selective multi-head self-attention (S-MSA) is well-designed to identify the representative instances by modeling the instance-to-instance interactions. On the contrary, a MIFD module with the information bottleneck is proposed to learn the discriminative fine-grained representation for histopathological images by modeling instance-to-bag interactions with the selected instances. Substantial experiments on five clinical benchmarks demonstrate that the MIST achieves accurate histopathological subtype prediction and obtains state-of-the-art performance with an accuracy of 0.936. The MIST shows great potential to handle fine-grained medical image analysis, such as histopathological subtype prediction in clinical applications.

20.
Int Immunopharmacol ; 138: 112586, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38955030

RESUMO

Nimodipine, a calcium antagonist, exert beneficial neurovascular protective effects in clinic. Recently, Calcium channel blockers (CCBs) was reported to protect against liver fibrosis in mice, while the exact effects of Nimodipine on liver injury and hepatic fibrosis remain unclear. In this study, we assessed the effect of nimodipine in Thioacetamide (TAA)-induced liver fibrosis mouse model. Then, the collagen deposition and liver inflammation were assessed by HE straining. Also, the frequency and phenotype of NK cells, CD4+T and CD8+T cells and MDSC in liver and spleen were analyzed using flow cytometry. Furthermore, activation and apoptosis of primary Hepatic stellate cells (HSCs) and HSC line LX2 were detected using α-SMA staining and TUNEL assay, respectively. We found that nimodipine administration significantly attenuated liver inflammation and fibrosis. And the increase of the numbers of hepatic NK and NKT cells, a reversed CD4+/CD8+T ratio, and reduced the numbers of MDSC were observed after nimodipine treatment. Furthermore, nimodipine administration significantly decreased α-SMA expression in liver tissues, and increased TUNEL staining adjacent to hepatic stellate cells. Nimodipine also reduced the proliferation of LX2, and significantly promoted high level of apoptosis in vitro. Moreover, nimodipine downregulated Bcl-2 and Bcl-xl, simultaneously increased expression of JNK, p-JNK, and Caspase-3. Together, nimodipine mediated suppression of growth and fibrogenesis of HSCs may warrant its potential use in the treatment of liver fibrosis.

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