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2.
Neural Regen Res ; 19(2): 425-433, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37488907

RESUMO

Temporal lobe epilepsy is a multifactorial neurological dysfunction syndrome that is refractory, resistant to antiepileptic drugs, and has a high recurrence rate. The pathogenesis of temporal lobe epilepsy is complex and is not fully understood. Intracellular calcium dynamics have been implicated in temporal lobe epilepsy. However, the effect of fluctuating calcium activity in CA1 pyramidal neurons on temporal lobe epilepsy is unknown, and no longitudinal studies have investigated calcium activity in pyramidal neurons in the hippocampal CA1 and primary motor cortex M1 of freely moving mice. In this study, we used a multi-channel fiber photometry system to continuously record calcium signals in CA1 and M1 during the temporal lobe epilepsy process. We found that calcium signals varied according to the grade of temporal lobe epilepsy episodes. In particular, cortical spreading depression, which has recently been frequently used to represent the continuously and substantially increased calcium signals, was found to correspond to complex and severe behavioral characteristics of temporal lobe epilepsy ranging from grade II to grade V. However, vigorous calcium oscillations and highly synchronized calcium signals in CA1 and M1 were strongly related to convulsive motor seizures. Chemogenetic inhibition of pyramidal neurons in CA1 significantly attenuated the amplitudes of the calcium signals corresponding to grade I episodes. In addition, the latency of cortical spreading depression was prolonged, and the above-mentioned abnormal calcium signals in CA1 and M1 were also significantly reduced. Intriguingly, it was possible to rescue the altered intracellular calcium dynamics. Via simultaneous analysis of calcium signals and epileptic behaviors, we found that the progression of temporal lobe epilepsy was alleviated when specific calcium signals were reduced, and that the end-point behaviors of temporal lobe epilepsy were improved. Our results indicate that the calcium dynamic between CA1 and M1 may reflect specific epileptic behaviors corresponding to different grades. Furthermore, the selective regulation of abnormal calcium signals in CA1 pyramidal neurons appears to effectively alleviate temporal lobe epilepsy, thereby providing a potential molecular mechanism for a new temporal lobe epilepsy diagnosis and treatment strategy.

3.
Talanta ; 266(Pt 2): 125127, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37647815

RESUMO

The application of flexible sensors in the biomedical field is deepening. It is of great significance to develop flexible wearable sensors which are more in line with the needs of the public. A flexible polylactic acid membrane fabric was prepared by electrospinning method. The membrane was used as SERS active substrate by screen printing capture probe which combine Au nanoplates with antibodies to the target substance. Thioglycolic acid-labeled silver nanoparticles coupled with antibodies as SERS nanotags. The target substance can be fixed between the capture probe and SERS nanotags. Due to the high specific surface area between the spinning, the adhesion rate of the capture probe is higher than that of the rigid substrate, and the enrichment and hypersensitivity detection of the object to be tested could be realized. The membranes prepared are flexible, wearable, portable, highly biocompatible, and can be mass-produced for high-throughput detection. We then applied the sensor to the detection of SARS-CoV-2 with detection limits as low as 10 TU/mL. This membrane as a SERS substrate can offer a fast and non-invasive reference for the early diagnosis of respiratory infectious diseases similar to COVID-19.


Assuntos
COVID-19 , Nanopartículas Metálicas , Pneumonia , Humanos , COVID-19/diagnóstico , SARS-CoV-2 , Prata , Anticorpos , Sistema Respiratório
4.
Food Chem ; 431: 137058, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37591143

RESUMO

A magnetic solid-phase extraction (MSPE) protocol using novel Urea-based magnetic covalent organic framework coupled with liquid chromatography-mass spectrometry was developed for the detection of coumarins in food samples (soft drink, biscuit and sesame paste). This adsorbent was synthesized through atom economic polymerization of tetrakis(4-aminophenyl) methane and 1,4-phenylene diisocyanate, which was successfully verified by a series of techniques. Major parameters influencing MSPE efficiency were optimized. This protocol had some advantages, such as organic-reagent-saving (2.0 mL), easy operating, short extraction time, and high repeatability (8 times). The established method exhibited superior linearity (R2 ≥ 0.999) and the limits of detection ranging from 1.0 to 5.0 µg/kg. The recoveries of coumarin and its derivatives ranged from 73.8% to 113.5% and both intra- and inter-day precision were less than 15%. These data indicate the protocol is a highly promising alternative for coumarin extraction and enrichment.


Assuntos
Estruturas Metalorgânicas , Cumarínicos , Cromatografia Líquida , Espectrometria de Massas , Ureia , Fenômenos Magnéticos
5.
Eur J Radiol ; 167: 111089, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37713969

RESUMO

OBJECTIVE: To estimate the potential of preoperative MRI features in the prediction of the integration patterns of vessels that encapsulate tumor clusters (VETC) and microvascular invasion (MVI) (VM) patterns in hepatocellular carcinoma (HCC) patients after resection and to assess the prognostic value of VM patterns. MATERIALS AND METHODS: Patients who underwent surgical resection for HCC between July 2019 and July 2020 were retrospectively included in the training cohort and validation cohort. In the training cohort, patients were classified into VM-positive HCC (VM-HCC) and VM-negative HCC (non-VM HCC). Predictors associated with VM-HCC were determined by using logistic regression analyses and used to build a prediction model of VM-HCC. The model was tested in the validation cohort by area under the receiver operating characteristic curve (AUC) analysis. Prognostic factors associated with early recurrence of HCC were evaluated by use of Cox logistic regression analyses. RESULTS: Alpha-fetoprotein (AFP) level higher than 400 ng/mL (odds ratio [OR] = 8.0; 95% CI: 2.6-25.2; P < 0.001), non-smooth tumor margin (OR = 3.1; 95% CI: 1.4-6.0; P < 0.001) and peritumoral arterial enhancement (OR = 2.9; 95% CI: 1.4-6.2; P = 0.004) were independent predictors of VM-HCC. The AUCs of the prediction model for VM-HCC were 0.81 for the training cohort and 0.79 for the validation cohort. The high risk of VM-HCC predicted by the three preoperative predictors derived from the prediction model (hazard ratio [HR] 2.0; 95% CI: 1.3, 3.2; P = 0.003) were independently associated with early recurrence, while pathologically confirmed VM-HCC (HR 2.8; 95% CI: 1.6, 3.8; P < 0.001) and satellite nodules (HR 1.8; 95% CI: 1.1, 3.1; P = 0.025) were independently associated with early recurrence after surgical resection. CONCLUSION: The predictive model can be used to predict VM patterns. VM-HCC is associated with increased risk of early recurrence after surgical resection in HCC.

6.
Nat Commun ; 14(1): 5727, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37714830

RESUMO

The poor efficacy of chimeric antigen receptor T-cell therapy (CAR T) for solid tumors is due to insufficient CAR T cell tumor infiltration, in vivo expansion, persistence, and effector function, as well as exhaustion, intrinsic target antigen heterogeneity or antigen loss of target cancer cells, and immunosuppressive tumor microenvironment (TME). Here we describe a broadly applicable nongenetic approach that simultaneously addresses the multiple challenges of CAR T as a therapy for solid tumors. The approach reprograms CAR T cells by exposing them to stressed target cancer cells which have been exposed to the cell stress inducer disulfiram (DSF) and copper (Cu)(DSF/Cu) plus ionizing irradiation (IR). The reprogrammed CAR T cells acquire early memory-like characteristics, potent cytotoxicity, enhanced in vivo expansion, persistence, and decreased exhaustion. Tumors stressed by DSF/Cu and IR also reprogram and reverse the immunosuppressive TME in humanized mice. The reprogrammed CAR T cells, derived from peripheral blood mononuclear cells of healthy donors or metastatic female breast cancer patients, induce robust, sustained memory and curative anti-solid tumor responses in multiple xenograft mouse models, establishing proof of concept for empowering CAR T by stressing tumor as a promising therapy for solid tumors.


Assuntos
Neoplasias da Mama , Receptores de Antígenos Quiméricos , Humanos , Feminino , Animais , Camundongos , Leucócitos Mononucleares , Microambiente Tumoral , Neoplasias da Mama/terapia , Modelos Animais de Doenças , Imunossupressores , Linfócitos T
7.
Risk Anal ; 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37700727

RESUMO

The occurrence of severe low-level wind shear (S-LLWS) events in the vicinity of airport runways poses a significant threat to flight safety and exacerbates a burgeoning problem in civil aviation. Identifying the risk factors that contribute to occurrences of S-LLWS can facilitate the improvement of aviation safety. Despite the significant influence of S-LLWS on aviation safety, its occurrence is relatively infrequent in comparison to non-SLLWS incidents. In this study, we develop an S-LLWS risk prediction model through the utilization of ensemble imbalance learning (EIL) strategies, namely, BalanceCascade, EasyEnsemble, and RUSBoost. The data for this study were obtained from PIREPs and LiDAR at Hong Kong International Airport. The analysis revealed that the BalanceCascade strategy outperforms EasyEnsemble and RUSBoost in terms of prediction performance. Afterward, the SHapley Additive exPlanations (SHAP) interpretation tool was used in conjunction with the BalanceCascade model for the risk assessment of various factors. The four most influential risk factors, according to the SHAP interpretation tool, were hourly temperature, runway 25LD, runway 25LA, and RWY (encounter location of LLWS). S-LLWS was likely to happen at Runway 25LD and Runway 25LA in temperatures ranging from low to moderate. Similarly, a high proportion of S-LLWS events occurred near the runway threshold, and a relatively small proportion occurred away from it. The EIL strategies in conjunction with the SHAP interpretation tool may accurately predict the S-LLWS without the need for data augmentation in the data pre-processing phase.

8.
mSystems ; : e0019723, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37702511

RESUMO

The N4-like viruses, which were recently assigned to the novel viral family Schitoviridae in 2021, belong to a podoviral-like viral lineage and possess conserved genomic characteristics and a unique replication mechanism. Despite their significance, our understanding of N4-like viruses is primarily based on viral isolates. To address this knowledge gap, this study has established a comprehensive N4-like viral data sets comprising 342 high-quality N4-like viruses/proviruses (144 viral isolates, 158 uncultured viruses, and 40 integrated N4-like proviruses). These viruses were classified into 97 subfamilies (89 of which are newly identified), 148 genera (100 of which are newly identified), and 253 species (177 of which are newly identified). The study reveals that N4-like viruses inhibit the polar region, oligotrophic open oceans, and the human gut, where they infect various bacterial lineages, such as Alpha/Beta/Gamma/Epsilon-proteobacteria in the Proteobacteria phylum. Although N4-like viral endogenization appears to be prevalent in Proteobacteria, it has also been observed in Firmicutes. Additionally, the phylogenetic analysis has identified evolutionary divergence within the hallmark genes of N4-like viruses, indicating a complex origin of the different conserved parts of viral genomes. Moreover, 1,101 putative auxiliary metabolic genes (AMGs) were identified in the N4-like viral pan-proteome, which mainly participate in nucleotide and cofactor/vitamin metabolisms. Of these AMGs, 27 were found to be associated with virulence, suggesting their potential involvement in the spread of bacterial pathogenicity. IMPORTANCE The findings of this study are significant, as N4-like viruses represent a unique viral lineage with a distinct replication mechanism and a conserved core genome. This work has resulted in a comprehensive global map of the entire N4-like viral lineage, including information on their distribution in different biomes, evolutionary divergence, genomic diversity, and the potential for viral-mediated host metabolic reprogramming. As such, this work significantly contributes to our understanding of the ecological function and viral-host interactions of bacteriophages.

9.
Artigo em Inglês | MEDLINE | ID: mdl-37668784

RESUMO

In order to efficiently recycle waste polyethylene terephthalate (PET) bottles, this study aimed to enhance the hydrolysis process to convert PET bottle into valuable terephthalic acid (TPA) by developing effective and reusable Ni/γ-Al2O3 catalysts. A series of Ni/γ-Al2O3 catalyst was prepared by the impregnation method with different Ni loadings (5-15 wt%) and was characterized by various techniques including XRD, SEM-EDX, and N2 adsorption-desorption. The prepared catalysts were employed in the catalytic hydrolysis of PET under varied influencing factors, namely reaction temperature (220-280 °C), reaction time (20-60 min), and Ni loading. The response surface methodology (RSM) was used to optimize the operating condition to produce the maximum TPA yield, and the optimal values were determined as follows: reaction temperature = 267.07 °C, reaction time = 48.54 min, and Ni loading = 12.90 wt%, giving the highest TPA yield of 97.06%. The R2, F-value, and P-value of the analysis of variance (ANOVA) were 0.9982, 424.96, and <0.0001, respectively, indicating a good fit of the model. The results from XRD and FTIR measurement of the produced TPA indicated the high purity and comparable chemical structures to the TPA standard. In addition, the 12.9Ni/Al catalyst exhibited high catalytic activity in repeated cycles of hydrolysis process of PET and could be regenerated by calcination to restore its catalytic activity. This finding could be a promising alternative for an effective TPA recovery from waste plastic bottles.

10.
Artigo em Inglês | MEDLINE | ID: mdl-37655831

RESUMO

PURPOSE: The aim of this study was to evaluate the efficacy and safety of moxifloxacin monotherapy for the treatment of uncomplicated pelvic inflammatory disease (uPID). METHODS: The literatures from PubMed, ScienceDirect, Google Scholar, Cochrane library and the http://clinicaltrials.gov/ were retrieved until February 2023. Only randomized controlled trials (RCTs) comparing the efficacy and safety of moxifloxacin with other antibiotics for treating uPID were included. The primary outcomes were clinical cure rate (CCR), bacteriological success rates (BSR) and risk of drug-related adverse events (AEs). We used random-effects modelled meta-analysis, trial sequential analysis, and the Grading of Recommendations Assessment, Development, and Evaluation. This study was registered in the International Prospective Register of Systematic Reviews (registration number: CRD42023428751). RESULTS: A total of four RCTs that enrolled 3201 women patients with uPID were included. In the per-protocol populations, no significant difference was observed between patients given moxifloxacin and those given other antibiotics with regard to CCR at test-of-cure (TOC) (2485 patients, odds ratio [OR] = 0.84, 95% confidence interval [CI] 0.68-1.04, p = 0.12). Similarly, there was no statistically significant difference between patients given moxifloxacin and those given other antibiotics in terms of BSR at TOC (471 patients, OR = 1.17, 95% CI 0.70-1.96, p = 0.56) in the microbiologically valid population. However, drug-related AEs occurred less frequently with moxifloxacin than with other antibiotics (2973 patients, OR = 0.74, 95% CI 0.64-0.86, p < 0.0001), especially gastrointestinal AEs (2973 patients, OR = 0.59, 95% CI 0.47-0.74, p < 0.00001). CONCLUSIONS: In the treatment of uPID, moxifloxacin monotherapy can achieve similar efficacy as other combination therapy regimens. Moreover, moxifloxacin had a better safety profile than that of comparators. Based on its additional advantages (i.e., better safety profile, no dosage adjustment and better compliance), moxifloxacin may be a more fascinating option compared with the currently used regimens.

11.
Opt Express ; 31(19): 31634-31643, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37710677

RESUMO

In this work, we fabricate a hybrid waveguide-grating vortex laser in Nd:YSAG by using femtosecond laser direct writing (FsLDW). The detailed parameters of the hybrid structure are fixed by optical simulation. In experiments, an efficient vortex beam is produced in the passive operation at 1064 nm. Under optical pumping at 808 nm, a dual-wavelength waveguide laser at 1060/1062 nm as well as a waveguide-grating vortex laser at 1060 nm are obtained. The laser performance and diffraction properties of the generated vortex laser are detailed, studied, and discussed, providing meaningful reference results toward the practical applications of FsLDW and waveguide-grating structures in integrated photonics.

12.
Anal Methods ; 15(35): 4591-4597, 2023 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-37655722

RESUMO

At present, there is no comprehensive and systematic research on laser-induced breakdown spectroscopy (LIBS) data visualization. In particular, the LIBS spectra of biological samples have large noise and weak signals, which seriously affect the feature visualization. Here, three commonly used sample visualization methods were compared, and a new method was applied for tissue sample visualization. We used the LIBS mapping technique to obtain LIBS spectra of different organ slice samples from mice. LIBS spectral distribution was visualized after extracting the region of interest. The three spectral visualization methods are compared, and the performance of visualization algorithms is quantitatively analyzed. The potential of heat-diffusion for the affinity-based transition embedding (PHATE) method highlights the details of the LIBS spectral distribution while maintaining the overall structure of the data. The correlation coefficient between dimensionality reduction data and raw data is 0.97, and the average distance between samples of different categories is 0.64, which are superior to those of traditional principal component analysis (PCA), multidimensional scaling (MDS), and t-distributed stochastic neighbor embedding (t-SNE). The results show that the PHATE method can serve as a very promising LIBS spectral visualization tool.

13.
Sci Total Environ ; : 166839, 2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37690761

RESUMO

Microcystins (MCs) can cause reproductive and developmental toxicity and disrupt endocrine homeostasis in mammals. In the present study, male, Sprague-Dawley (SD) rats were administrated 3 or 30 µg MC-LR/kg, body mass (bm) per day via intraperitoneal (i.p.) injections for 6 weeks. Effects of MC-LR on histology, hormone concentrations, gene transcriptional profiles and protein expressions along the hypothalamic-pituitary-adrenal (HPA), -gonad (HPG) and -thyroid (HPT) axes were assessed. Sub-chronic administration with MC-LR caused histological damage to hypothalamus, pituitary, adrenal, testes and thyroid and affected relative masses of pituitary, adrenal and testes. The HPA axis was activated and serum concentrations of corticotropin-releasing hormone (CRH), adrenocorticotropic hormone (ACTH) and corticosterone (CORT) were significantly augmented. Along the HPG axis, serum concentrations of gonadotropin-releasing hormone (GnRH) and dihydrotestosterone (DHT) were diminished, while concentrations of luteinizing hormone (LH), follicle-stimulating hormone (FSH), testosterone (T) and estradiol (E2) were greater. For the HPT axis, only concentrations of free tetra-iodothyronine (fT4) were significantly diminished, while concentrations of thyrotropin-releasing hormone (TRH), thyroid-stimulating hormone (TSH) or free tri-iodothyronine (fT3) were not significantly changed. Also, several genes and proteins related to synthesis of steroid hormones were significantly altered. Findings of the present study illustrate that MC-LR can cause endocrine-disrupting effects through the disruption of negative feedback regulation of the HPA, HPG and HPT axes, and the synthesis and secretion of hormones. Also, there could be crosstalk among HPA, HPG and HPT axes. These findings elucidate mechanisms of endocrine-disrupting effects of MCs.

15.
J Glob Health ; 13: 04107, 2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37681663

RESUMO

Background: Over the past 70 years, China has advanced significantly in the prevention and treatment of infectious diseases while simultaneously undergoing a socioeconomic transformation, making it a useful source of data for analysing relationships between public health policy and the control of infectious diseases. Methods: We collected data on the incidence of notifiable infectious diseases and associated fatalities in Jiangsu province in southeast China from the Provincial Center for Disease Control and Prevention, Provincial Institute of Parasitic Diseases, and the Nationwide Notifiable Infectious Diseases Reporting Information System. We compared data from different historical periods using descriptive statistical methods, joinpoint regression, and correlation analysis. Results: During 1950-2022, 75 754 008 cases of 46 notifiable infectious diseases were reported in Jiangsu, with an average annual incidence was 1679.49 per 100 000 population and a fatality rate of 1.82 per 1000 persons. The incidence of classes A-B decreased (average annual percent change (AAPC) = -2.1) during the entire study period, while the incidence of class C increased (AAPC = 10.8) after 2004. The incidence of intestinal diseases (AAPC = -4.4) and vector-borne and zoonotic diseases (AAPC = -8.1) decreased rapidly, while the incidence of sexually transmitted and blood-borne diseases (AAPC = 1.8) increased. The number of medical and health institutions and the per capita gross domestic product correlated negatively with the annual incidence of diseases in classes A-B, but not with fatality rates. Conclusions: Although the annual incidence of many severe infectious diseases has decreased in Jiangsu since 1950, the incidence of sexually transmitted and blood-borne diseases increased. Socioeconomic growth and sustainable investment in health systems are associated with better control of infectious diseases.


Assuntos
Doenças Transmissíveis , Humanos , Animais , Incidência , Doenças Transmissíveis/epidemiologia , Zoonoses , China/epidemiologia , Fatores Socioeconômicos
16.
Opt Lett ; 48(17): 4532-4535, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37656546

RESUMO

Bound states in the continuum (BICs) are intriguing localized states that possess eigenvalues embedded within the continuum of extended states. Recently, a combination of topological band theory and BIC physics has given rise to a novel form of topological matter known as topological BICs. In this work, we experimentally demonstrate the photonic topological subspace-induced BICs. By using femtosecond-laser writing, we experimentally establish a photonic nontrivial three-leg ladder lattice, thereby directly observe the localized propagation of two kinds of topological edge states which exist at different boundaries. Interestingly, such edge states appear in the continuum of the bulk modes, and the topological properties are inherited from its independent subspace Hamiltonian which contains a celebrated Su-Schrieffer-Heeger lattice. This work not only presents a novel, to the best of our knowledge, platform for investigating topological physics in optics, but also unveils exciting prospects for future exploration of other remarkable BICs.

17.
Phys Rev Lett ; 131(7): 073201, 2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37656843

RESUMO

Discrimination of entangled states is an important element of quantum-enhanced metrology. This typically requires low-noise detection technology. Such a challenge can be circumvented by introducing nonlinear readout process. Traditionally, this is realized by reversing the very dynamics that generates the entangled state, which requires a full control over the system evolution. In this Letter, we present nonlinear readout of highly entangled states by employing reinforcement learning to manipulate the spin-mixing dynamics in a spin-1 atomic condensate. The reinforcement learning found results in driving the system toward an unstable fixed point, whereby the (to be sensed) phase perturbation is amplified by the subsequent spin-mixing dynamics. Working with a condensate of 10 900 ^{87}Rb atoms, we achieve a metrological gain of 6.97_{-1.38}^{+1.30} dB beyond the classical precision limit. Our work will open up new possibilities in unlocking the full potential of entanglement caused quantum enhancement in experiments.

18.
Light Sci Appl ; 12(1): 223, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37696802

RESUMO

Whispering-gallery-mode microcavity lasers possess remarkable characteristics such as high Q factors and compact geometries, making them an essential element in the evolution of microlasers. However, solid-state whispering-gallery-mode lasers have previously suffered from low output power and limited optical conversion efficiency, hindering their applications. Here, we present the achievement of milliwatt laser emissions at a wavelength of 1.06 µm from a solid-state whispering-gallery-mode laser. To accomplish this, we construct a whispering-gallery-mode microcavity (with a diameter of 30 µm) using a crystalline Nd: YAG thin film obtained through carbon-implantation enhanced etching of a Nd: YAG crystal. This microcavity laser demonstrates a maximum output power of 1.12 mW and an optical conversion efficiency of 12.4%. Moreover, our unique eccentric microcavity design enables efficient coupling of free-space pump light, facilitating integration with a waveguide. This integration allowed for single-wavelength laser emission from the waveguide, achieving an output power of 0.5 mW and an optical conversion efficiency of 6.18%. Our work opens up new possibilities for advancing solid-state whispering-gallery-mode lasers, providing a viable option for compact photonic sources.

19.
Inorg Chem ; 62(37): 14863-14872, 2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37676750

RESUMO

Cooperative spin crossover transitions with thermal hysteresis loops are rarely observed in cobalt(II) complexes. Herein, two new mononuclear cobalt(II) complexes with hysteretic spin crossover at relatively high temperatures (from 320 to 400 K), namely, [Co(terpy-CH2OH)2]·X2 (terpy-CH2OH = 4'-(hydroxymethyl)-2,2';6',2″-terpyridine, X = SCN-(1) and SeCN- (2)), have been synthesized and characterized structurally and magnetically. Both compounds are mononuclear CoII complexes with two chelating terpy-CH2OH ligands. Magnetic measurements revealed the existence of the hysteretic SCO transitions for both complexes. For compound 1, a one-step transition with T1/2↑= 334.5 K was observed upon heating, while a two-step transition is observed upon cooling with T1/2↓(1) = 329.3 K and T1/2↓(2) = 324.1 K (at a temperature sweep rate of 5 K/min). As for compound 2, a hysteresis loop with a width of 5 K (T1/2↓ = 391.6 K and T1/2↑ = 396.6 K, at a sweep rate of 5 K/min) can be observed. Thanks to the absence of the crystallized lattice solvents, their single crystals are stable enough at high temperatures for the structure determination at both spin states, which reveals that the hysteretic SCO transitions in both complexes originate from the crystallographic phase transitions involving a thermally induced order-disorder transition of the dangling -CH2OH groups in the ligand. This work shows that the modification of the terpy ligand has an important effect on the magnetic properties of the resulting cobalt(II) complexes.

20.
Eur J Med Res ; 28(1): 351, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37715244

RESUMO

BACKGROUND: The incidence of rebleeding in patients with upper gastrointestinal bleeding (UGIB) remains despite advances in intervention approaches. Therefore, early prediction of the risk of rebleeding could help to greatly reduce the mortality rate in these patients. We aim to develop and validate a new prediction model to predict the probability of rebleeding in patients with AUGIB. METHODS: A total of 1170 AUGIB patients who completed the procedure of emergency gastroscopy within 48 h of admission were included. Logistic regression analyses were performed to construct a new prediction model. A receiver operating characteristic curve, a line graph, and a calibration and decision curve were used to assess the predictive performance of our new prediction model and compare its performance with that of the AIMS65 scoring system to determine the predictive value of our prediction model. RESULTS: A new prediction model was constructed based on Lactic acid (LAC), neutrophil percentage (NEUTP), platelet (PLT), albumin (ALB), and D-DIMER. The AUC values and their 95% confidence interval (CI) for the new prediction model and the AIMS65 score were 0.746 and 0.619, respectively, and 0.697-0.795 and 0.567-0.670, respectively. In the training group, the C index values based on the prediction model and the AIMS65 scoring system were 0.720 and 0.610, respectively. In the validation group, the C index values based on the prediction model and the AIMS65 scoring system were 0.828 and 0.667, respectively. The decision and calibration curve analysis also showed that the prediction model was superior to the AIMS65 scoring system in terms of accuracy of prediction, consistency, and net clinical benefit. CONCLUSION: The prediction model can predict the probability of rebleeding in AUGIB patients after endoscopic hemostasis therapy.


Assuntos
Hemorragia Gastrointestinal , Gastroscopia , Humanos , Hospitalização , Ácido Láctico , Neutrófilos
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