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The early evolution of a supernova (SN) can reveal information about the environment and the progenitor star. When a star explodes in vacuum, the first photons to escape from its surface appear as a brief, hours-long shock-breakout flare1,2, followed by a cooling phase of emission. However, for stars exploding within a distribution of dense, optically thick circumstellar material (CSM), the first photons escape from the material beyond the stellar edge and the duration of the initial flare can extend to several days, during which the escaping emission indicates photospheric heating3. Early serendipitous observations2,4 that lacked ultraviolet (UV) data were unable to determine whether the early emission is heating or cooling and hence the nature of the early explosion event. Here we report UV spectra of the nearby SN 2023ixf in the galaxy Messier 101 (M101). Using the UV data as well as a comprehensive set of further multiwavelength observations, we temporally resolve the emergence of the explosion shock from a thick medium heated by the SN emission. We derive a reliable bolometric light curve that indicates that the shock breaks out from a dense layer with a radius substantially larger than typical supergiants.
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The development of high-performance ultraelastic metals with superb strength, a large elastic strain limit and temperature-insensitive elastic modulus (Elinvar effect) are important for various industrial applications, from actuators and medical devices to high-precision instruments1,2. The elastic strain limit of bulk crystalline metals is usually less than 1 per cent, owing to dislocation easy gliding. Shape memory alloys3-including gum metals4,5 and strain glass alloys6,7-may attain an elastic strain limit up to several per cent, although this is the result of pseudo-elasticity and is accompanied by large energy dissipation3. Recently, chemically complex alloys, such as 'high-entropy' alloys8, have attracted tremendous research interest owing to their promising properties9-15. In this work we report on a chemically complex alloy with a large atomic size misfit usually unaffordable in conventional alloys. The alloy exhibits a high elastic strain limit (approximately 2 per cent) and a very low internal friction (less than 2 × 10-4) at room temperature. More interestingly, this alloy exhibits an extraordinary Elinvar effect, maintaining near-constant elastic modulus between room temperature and 627 degrees Celsius (900 kelvin), which is, to our knowledge, unmatched by the existing alloys hitherto reported.
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The final fate of massive stars, and the nature of the compact remnants they leave behind (black holes and neutron stars), are open questions in astrophysics. Many massive stars are stripped of their outer hydrogen envelopes as they evolve. Such Wolf-Rayet stars1 emit strong and rapidly expanding winds with speeds greater than 1,000 kilometres per second. A fraction of this population is also helium-depleted, with spectra dominated by highly ionized emission lines of carbon and oxygen (types WC/WO). Evidence indicates that the most commonly observed supernova explosions that lack hydrogen and helium (types Ib/Ic) cannot result from massive WC/WO stars2,3, leading some to suggest that most such stars collapse directly into black holes without a visible supernova explosion4. Here we report observations of SN 2019hgp, beginning about a day after the explosion. Its short rise time and rapid decline place it among an emerging population of rapidly evolving transients5-8. Spectroscopy reveals a rich set of emission lines indicating that the explosion occurred within a nebula composed of carbon, oxygen and neon. Narrow absorption features show that this material is expanding at high velocities (greater than 1,500 kilometres per second), requiring a compact progenitor. Our observations are consistent with an explosion of a massive WC/WO star, and suggest that massive Wolf-Rayet stars may be the progenitors of some rapidly evolving transients.
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Fast radio bursts (FRBs) are highly dispersed, millisecond-duration radio bursts1-3. Recent observations of a Galactic FRB4-8 suggest that at least some FRBs originate from magnetars, but the origin of cosmological FRBs is still not settled. Here we report the detection of 1,863 bursts in 82 h over 54 days from the repeating source FRB 20201124A (ref. 9). These observations show irregular short-time variation of the Faraday rotation measure (RM), which scrutinizes the density-weighted line-of-sight magnetic field strength, of individual bursts during the first 36 days, followed by a constant RM. We detected circular polarization in more than half of the burst sample, including one burst reaching a high fractional circular polarization of 75%. Oscillations in fractional linear and circular polarizations, as well as polarization angle as a function of wavelength, were detected. All of these features provide evidence for a complicated, dynamically evolving, magnetized immediate environment within about an astronomical unit (AU; Earth-Sun distance) of the source. Our optical observations of its Milky-Way-sized, metal-rich host galaxy10-12 show a barred spiral, with the FRB source residing in a low-stellar-density interarm region at an intermediate galactocentric distance. This environment is inconsistent with a young magnetar engine formed during an extreme explosion of a massive star that resulted in a long gamma-ray burst or superluminous supernova.
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Fast radio bursts (FRBs) are millisecond-duration radio transients of unknown physical origin observed at extragalactic distances1-3. It has long been speculated that magnetars are the engine powering repeating bursts from FRB sources4-13, but no convincing evidence has been collected so far14. Recently, the Galactic magnetar SRG 1935+2154 entered an active phase by emitting intense soft γ-ray bursts15. One FRB-like event with two peaks (FRB 200428) and a luminosity slightly lower than the faintest extragalactic FRBs was detected from the source, in association with a soft γ-ray/hard-X-ray flare18-21. Here we report an eight-hour targeted radio observational campaign comprising four sessions and assisted by multi-wavelength (optical and hard-X-ray) data. During the third session, 29 soft-γ-ray repeater (SGR) bursts were detected in γ-ray energies. Throughout the observing period, we detected no single dispersed pulsed emission coincident with the arrivals of SGR bursts, but unfortunately we were not observing when the FRB was detected. The non-detection places a fluence upper limit that is eight orders of magnitude lower than the fluence of FRB 200428. Our results suggest that FRB-SGR burst associations are rare. FRBs may be highly relativistic and geometrically beamed, or FRB-like events associated with SGR bursts may have narrow spectra and characteristic frequencies outside the observed band. It is also possible that the physical conditions required to achieve coherent radiation in SGR bursts are difficult to satisfy, and that only under extreme conditions could an FRB be associated with an SGR burst.
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The optimal treatment for tracheal tumors necessitates sequential tumor elimination and tracheal cartilage reconstruction. This study introduces an innovative inorganic nanosheet, MnO2 /PDA@Cu, comprising manganese dioxide (MnO2 ) loaded with copper ions (Cu) through in situ polymerization using polydopamine (PDA) as an intermediary. Additionally, a specialized methacrylic anhydride modified decellularized cartilage matrix (MDC) hydrogel with chondrogenic effects is developed by modifying a decellularized cartilage matrix with methacrylic anhydride. The MnO2 /PDA@Cu nanosheet is encapsulated within MDC-derived microneedles, creating a photothermal-controllable MnO2 /PDA@Cu-MDC microneedle. Effectiveness evaluation involved deep insertion of the MnO2 /PDA@Cu-MDC microneedle into tracheal orthotopic tumor in a murine model. Under 808 nm near-infrared irradiation, facilitated by PDA, the microneedle exhibited rapid overheating, efficiently eliminating tumors. PDA's photothermal effects triggered controlled MnO2 and Cu release. The MnO2 nanosheet acted as a potent inorganic nanoenzyme, scavenging reactive oxygen species for an antioxidant effect, while Cu facilitated angiogenesis. This intervention enhanced blood supply at the tumor excision site, promoting stem cell enrichment and nutrient provision. The MDC hydrogel played a pivotal role in creating a chondrogenic niche, fostering stem cells to secrete cartilaginous matrix. In conclusion, the MnO2 /PDA@Cu-MDC microneedle is a versatile platform with photothermal control, sequentially combining antitumor, antioxidant, pro-angiogenic, and chondrogenic activities to orchestrate precise tracheal tumor eradication and cartilage regeneration.
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Nanopartículas , Neoplasias , Neoplasias da Traqueia , Humanos , Camundongos , Animais , Antioxidantes , Compostos de Manganês , Óxidos , Neoplasias/patologia , Cartilagem , Hidrogéis , AnidridosRESUMO
The slow transition from an out-of-equilibrium glass towards a supercooled liquid is a complex relaxation phenomenon. In this Letter, we study the correlation between mechanical relaxation and equilibration kinetics in a Pd_{20}Pt_{20}Cu_{20}Ni_{20}P_{20} high-entropy metallic glass. The evolution of stress relaxation with aging time was obtained with an unprecedented detail, allowing us to pinpoint new interesting features. The long structural relaxation towards equilibrium contains a wide distribution of activation energies, instead of being just associated to the ß relaxation as commonly accepted. The stress relaxation time can be correlated with the equilibration rate and we observe a decrease of microstructural heterogeneity which contrasts with an increase of dynamic heterogeneity. These results significantly enhance our insight of the interplay between relaxation dynamics and thermodynamics in metallic glasses.
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We report the picosecond spin current generation from the interface between a heavy metal and a vicinal antiferromagnet insulator Cr_{2}O_{3} by laser pulses at room temperature and zero magnetic field. It is converted into a detectable terahertz emission in the heavy metal via the inverse spin Hall effect. The vicinal interfaces are apparently the source of the picosecond spin current, as evidenced by the proportional terahertz signals to the vicinal angle. We attribute the origin of the spin current to the transient magnetic moment generated by an interfacial nonlinear magnetic-dipole difference-frequency generation. We propose a model based on the in-plane inversion symmetry breaking to quantitatively explain the terahertz intensity with respect to the angles of the laser polarization and the film azimuth. Our work opens new opportunities in antiferromagnetic and ultrafast spintronics by considering symmetry breaking.
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OBJECTIVE: To investigate outcomes of a novel, off the shelf multibranched endovascular stent graft for the treatment of thoraco-abdominal aortic aneurysm (TAAA) and pararenal abdominal aortic aneurysm (PAAA). METHODS: A prospective, single centre study including 15 patients (mean age, 63.4 ± 10.7 years; 13 male) with TAAA or PAAA treated from October 2019 to March 2021 with a G-Branch endograft (Lifetech Scientific, Shenzhen, China) featuring a mixed multibranch design with two inner and two outer branches for reconstruction of the visceral and bilateral renal arteries, respectively. Follow up assessments were scheduled before discharge and at 30 days, six and 12 months after the index procedure. Annual telephone interviews were performed beyond the initial 12 months. The Kaplan-Meier method was used to estimate cumulative mortality and morbidity rates after endovascular repair. RESULTS: Technical success was achieved in all 15 patients. Nine patients (60%) had TAAA and six (40%) had PAAA (mean maximum aneurysm diameter, 73.7 ± 15.8 mm). The median follow up was 31.4 months (range, 10.1 - 44.0 months). At 30 days, there was no death and 7% morbidity (one case of temporary spinal cord ischaemia on Day 4). At one year, the mortality rate was 7% (one death from stroke at 10 months) and morbidity was 13% (one other case of renal function decline at six months). There were no aneurysm dilatations, re-interventions, or access related complications, and two (13%) persistent type II endoleaks. The one year primary branch patency rate was 100% for the four renovisceral arteries in all 13 patients who underwent computed tomography examinations. One patient died of hepatocellular carcinoma 29 months post-operatively, resulting in an estimated three year mortality rate of 13%. CONCLUSION: The G-Branch endograft yielded high technical success with good early and midterm outcomes for the treatment of TAAA and PAAA. A large multicentre study is warranted.
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Aneurisma da Aorta Abdominal , Aneurisma da Aorta Torácica , Implante de Prótese Vascular , Procedimentos Endovasculares , Humanos , Masculino , Pessoa de Meia-Idade , Idoso , Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/efeitos adversos , Aneurisma da Aorta Torácica/cirurgia , Estudos Prospectivos , Resultado do Tratamento , Complicações Pós-Operatórias/etiologia , Fatores de Tempo , Stents/efeitos adversos , Aneurisma da Aorta Abdominal/cirurgia , Artéria Renal/cirurgia , Procedimentos Endovasculares/efeitos adversos , Desenho de PróteseRESUMO
AIM: To investigate the prognostic impact of computed tomography (CT)-defined ground glass opacity (GGO) in patients with clinical stage I-IIA grade 3 invasive non-mucinous pulmonary adenocarcinoma (INPA). MATERIALS AND METHODS: The present study retrospectively enrolled 187 patients diagnosed with stage I-IIA grade 3 INPA. Their clinicopathological, radiological, and genetic information was evaluated systematically, and a 5-year follow-up was conducted to monitor disease recurrence and mortality. Patients were stratified based on the presence of a GGO component, and the Cox proportional hazard model was employed to assess the influence of clinicopathological factors and genetic variables on tumour outcomes. Recurrence-free survival (RFS) and overall survival (OS) were estimated using the Kaplan-Meier method and compared using the log-rank test. RESULTS: Significant differences were observed in both OS and RFS based on the presence of a GGO component. The group with GGO exhibited superior OS (p=0.002) and RFS (p=0.029). Multivariate analysis revealed that the presence of a GGO component (hazard ratio [HR] = 0.412, 95% confidence interval [CI]: 0.177-0.959, p=0.040), clinical T2 stage (HR=2.473, 95% CI: 1.498-4.083, p<0.001), pathological N2 stage (HR=3.049, 95% CI: 1.800-5.167, p<0.001), and mixed high-grade patterns (HR=2.392, 95% CI: 1.418-4.036, p=0.001) were predictors of RFS. CONCLUSION: The presence of a GGO component is strongly associated with a favourable prognosis in grade 3 INPA.
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Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Humanos , Prognóstico , Neoplasias Pulmonares/patologia , Estudos Retrospectivos , Estadiamento de Neoplasias , Recidiva Local de Neoplasia/patologia , Adenocarcinoma de Pulmão/patologia , Tomografia Computadorizada por Raios XRESUMO
AIM: To investigate whether dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) has the potential to non-invasively detect microenvironmental condition by quantitatively measuring blood perfusion, vessel wall permeability, and vascularity, and to elucidate the possible correlations between DCE-MRI quantitative parameters and the expression level of hypoxia, vascularity, and cell proliferation related molecular biomarkers. MATERIALS AND METHODS: In this prospective single center clinical study, 58 patients diagnosed with cervical cancer underwent DCE-MRI before anticancer treatment were enrolled. Ktrans, Kep, Ve, and Vp were generated from Extended Toft's model. Then patients conducted colposcopy biopsy within 1 week after DCE-MRI. Pretreatment expression levels of HIF-1α, VEGF and Ki-67 were assessed and scored by immunohistochemistry on colposcopy obtained tumor specimens. RESULTS: In HIF-1α low-expression group, Ktrans (p=0.031) and Kep (p=0.012) values were significantly higher than the high-expression group. In VEGF high-expression group, Ktrans (p=0.044) and Ve values (p=0.021) were significantly higher than the low-expression group. In Ki-67 high-expression group, Ktrans (p=0.026) and Kep (p=0.033) were significantly higher than the low-expression group. Multiple linear regression analyses and Pearson correlation revealed that Ktrans independently negatively correlated with HIF-1α expression, Ve independently positively correlated with VEGF, and Kep independently positively correlated with Ki-67. The area under the ROC curves of Ktrans for HIF-1α, Ve for VEGF, and Kep for Ki-67 were 0.728, 0.743, 0.730, respectively. CONCLUSION: Our results suggest that DCE-MRI quantitative parameters could be potentially used as imaging markers for non-invasively detecting microenvironmental hypoxia, vascularity and proliferation in cervical cancer patients.
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Biomarcadores Tumorais , Subunidade alfa do Fator 1 Induzível por Hipóxia , Antígeno Ki-67 , Neoplasias do Colo do Útero , Fator A de Crescimento do Endotélio Vascular , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Biomarcadores Tumorais/metabolismo , Meios de Contraste , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Antígeno Ki-67/metabolismo , Imageamento por Ressonância Magnética/métodos , Estudos Prospectivos , Neoplasias do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/irrigação sanguínea , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
AIM: The objective of this study is to explore the diagnostic value of machine learning (ML) in borderline ovarian tumors through meta-analysis. METHODS: Pubmed, Embase, Web of Science, and Cochrane Library databases were comprehensively retrieved from database inception untill February 16, 2023. The Prediction Model Risk of Bias Assessment Tool (PROBAST) was adopted to evaluate the risk of bias in the original studies. Sub-group analyses of ML were conducted according to clinical features and radiomics features. We separately discussed the discriminative value of ML for borderline vs benign and borderline vs malignant tumors. RESULTS: Eighteen studies involving 12,778 subjects were included in our analysis. The modeling variables mainly consisted of radiomics features (n=13) and a small number of clinical features (n=5). When distinguishing between borderline and benign tumors, the ML model based on radiomic features achieved a c-index of 0.782 (95% CI: 0.732-0.831), sensitivity of 0.75 (95% CI: 0.67-0.82), and specificity of 0.75 (95% CI: 0.67-0.81) in the validation set. When distinguishing between borderline and malignant tumors, the ML model based on radiomic features achieved a c-index of 0.916 (95% CI: 0.891-0.940), sensitivity of 0.86 (95% CI: 0.78-0.91), and specificity of 0.88 (95% CI: 0.82-0.92) in the validation set. In addition, we analyzed the discriminatory ability of radiologists and found that their sensitivity was 0.26 (95% CI: 0.12-0.46) and specificity was 0.94 (95% CI: 0.90-0.97). CONCLUSIONS: ML has tremendous potential in the preoperative diagnosis and differentiation of borderline ovarian tumors and may be more accurate than radiologists in diagnosing and differentiating borderline ovarian tumors.
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Aprendizado de Máquina , Neoplasias Ovarianas , Humanos , Feminino , Neoplasias Ovarianas/diagnóstico por imagem , Sensibilidade e Especificidade , Ovário/diagnóstico por imagem , Diagnóstico Diferencial , Reprodutibilidade dos TestesRESUMO
AIM: To develop and validate a non-invasive computed tomography (CT)-based radiomics model for predicting vasculogenic mimicry (VM) status in lung adenocarcinoma (LA). MATERIALS AND METHODS: Two hundred and three patients with LA were enrolled retrospectively and grouped into training and test groups with a ratio of 7:3. Uni- and multivariate logistic regression analyses were performed in the training cohort to screen the independent clinical and radiological factors for VM, and the clinical model was then established. A radiomics model was established based on the rad-scores through support vector machine (SVM). A radiomics nomogram model was subsequently constructed by combining the rad-score with clinical-radiological factors. The receiver operating characteristic curve (ROC), calibration curves, and decision curve analysis (DCA) were conducted to evaluate the performance of the three models. RESULTS: Nine selected radiomics features were selected for the radiomics model and the maximum length and spiculation sign were constructed for the clinical model. The radiomics nomogram model integrating the maximum length, spiculation sign, and rad-score yielded the best AUC in both the training (AUC = 0.925) and test cohorts (AUC = 0.978), in comparison with the radiomics model (AUC = 0.907 and 0.964, in both the training and test cohorts) and the clinical model (AUC = 0.834 and 0.836 in both training and test cohorts). CONCLUSIONS: The CT-based radiomics nomogram model showed satisfying discriminating performance for preoperatively and non-invasively predicting VM expression status in LA patients.
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Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Humanos , Radiômica , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Adenocarcinoma de Pulmão/diagnóstico por imagem , Nomogramas , Neoplasias Pulmonares/diagnóstico por imagemRESUMO
AIMS: SIRT1 deficiency has been associated with diabetes, and a variant of the SIRT1 gene has been found to be involved in human autoimmune diabetes; however, it is unclear whether this genetic variation exists in Han Chinese with type 1 diabetes (T1D) and whether it contributes to development of T1D. Therefore, we aimed to explore the association of the SIRT1 gene single-nucleotide polymorphisms (SNPs) rs10997866 and rs3818292 in a Han Chinese population with T1D. METHODS: This study recruited 2653 unrelated Han Chinese individuals, of whom 1289 had T1D and 1364 were healthy controls. Allelic and genotypic distributions of SIRT1 polymorphisms (rs10997866 and rs3818292) were determined by MassARRAY. Basic characteristics, genotype and allele frequencies of selected SNPs were compared between the T1D patients and healthy controls. Further genotype-phenotype association analysis of the SNPs was performed on the T1D patients divided into three groups according to genotype. Statistical analyses included the chi-square test, MannâWhitney U test, KruskalâWallis H test and logistic regression. RESULTS: The allelic (G vs. A) and genotypic (GA vs. AA) distributions of SIRT1 rs10997866 were significantly different in T1D patients and healthy controls (P = 0.039, P = 0.027), and rs10997866 was associated with T1D susceptibility under dominant, overdominant and additive models (P = 0.026, P = 0.030 and P = 0.027, respectively). Moreover, genotype-phenotype association analysis showed the GG genotype of rs10997866 and the GG genotype of rs3818292 to be associated with higher titers of IA-2A (P = 0.013 and P = 0.038, respectively). CONCLUSION: SIRT1 rs10997866 is significantly associated with T1D susceptibility, with the minor allele G conferring a higher risk of T1D. Moreover, SIRT1 gene rs10997866 and rs3818292 correlate with the titer of IA-2A in Han Chinese individuals with T1D.
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Diabetes Mellitus Tipo 1 , Humanos , Diabetes Mellitus Tipo 1/genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Sirtuína 1/genética , Genótipo , Frequência do Gene , Alelos , Estudos de Casos e Controles , ChinaRESUMO
Oxidative stress is the imbalanced redox status between oxidant production and their scavengers leading to intestinal physiological dysfunction. However, the role of systemic and local oxidative status during neonatal calf diarrhea is not known. This study assessed systemic (serum) and local (fecal) oxidative status when calves either naturally developed diarrhea or naturally recovered. Healthy calves were enrolled in the study at d 18 of age, and their health status was monitored from the enrollment. Based on their enteric health status on d 21 and 28, calves were grouped as continuous diarrhea from d 21 to 28 (n = 14), diarrhea at d 21 but recovered at d 28 (DH group, n = 19), healthy at d 21 but developed diarrhea at d 28 (HD group, n = 15), and healthy throughout the study (HH group, n = 16). Serum and fecal samples were collected at d 21 and 28 from all calves in the morning 2 h after feeding. Dynamics of oxidative stress indicators including reactive oxygen species (ROS), malondialdehyde (MDA), H2O2, 8-hydroxy-2'-deoxyguanosine (8-OHDG), glutathione peroxidase, superoxide dismutase, catalase (CAT), and total antioxidant capacity and inflammatory indicators TNF-α, IL-1ß, IL-4, IL-6, IL-10, and IFN-γ were evaluated using serum samples. In addition, fecal oxidative stress indicators ROS and MDA were measured. Serum ROS, MDA, 8-OHDG, as well as fecal ROS and MDA, were higher, whereas serum CAT and H2O2 were lower in diarrheic calves than those of healthy calves. Serum ROS, MDA, and 8OHDG and fecal ROS and MDA increased in the HD group from d 21 to 28 as they developed diarrhea. In contrast, all these oxidative stress markers decreased in the DH group from d 21 to 28 as they recovered. However, serum H2O2 had an opposite changing trend, which became lower in the HD group and higher in the DH group at d 28. In conclusion, both systemic and local oxidative stress markers and cytokine profiles altered as calves moved from being healthy to having diarrhea or vice versa. Serum ROS, MDA, and 8-OHDG can be used to develop biomarkers to screen calves prone to enteric infections during the preweaning period.
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Peróxido de Hidrogênio , Estresse Oxidativo , Animais , Bovinos , Espécies Reativas de Oxigênio , Diarreia/veterinária , ImunidadeRESUMO
BACKGROUND: Spatial abilities are fundamental cognitive abilities, have direct applications in daily life, serve as a cognitive foundation for many other complex skills and are used in many specialty jobs. The current study aimed to systematically and comprehensively evaluate the spatial abilities of individuals with Down syndrome (DS) relative to mental ability-matched typically developing (TD) children based on Newcombe and Shipley's double-dimension theoretical framework for classifying spatial abilities. METHODS: Forty adolescents and young adults with DS and 40 TD children completed a nonverbal intelligence test (Raven's), two measures of static-extrinsic skills (water-level task and cart task), two measures of static-intrinsic skills (figure ground and form completion), two measures of dynamic-extrinsic skills (three mountains task and dog task) and two measures of dynamic-intrinsic spatial skills (mental rotation task and block design task). RESULTS: Participants with DS showed reduced performance on two dynamic-intrinsic tasks and one static-extrinsic task (i.e. cart task) relative to TD children. Performances were similar in two dynamic-extrinsic tasks and two static-intrinsic tasks. Analyses of composite accuracy for each spatial category further confirmed deficits in dynamic-intrinsic and static-extrinsic categories for people with DS relative to TD children. CONCLUSIONS: Our results showed an uneven profile of spatial abilities in people with DS relative to ability-matched TD children with particular weaknesses in comprehending and manipulating dynamic-intrinsic and static-extrinsic spatial relations. Furthermore, our research has important clinical implications for more targeted interventions to improve spatial abilities in people with DS.
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Síndrome de Down , Navegação Espacial , Adolescente , Criança , Humanos , Adulto Jovem , Aptidão , Cognição , Síndrome de Down/psicologiaRESUMO
OBJECTIVES: Hospices are regarded as gold standard providers of end-of-life care. The term hospice, however, is broadly used, and can describe a type of care offered in a variety of health care services (e.g. nursing homes). It thus becomes complex for families to decide between services. We aimed to review the evidence around the experience of family carers of people with dementia accessing in-patient hospice settings for end-of-life care. METHOD: We registered the review protocol on PROSPERO. We used PerSPE(C)TiF to systematically organise our search strategy. The evidence was reviewed across six databases: PubMed, EMBASE, PsycINFO, ASSIA, ISI Web, and CINAHL. We used meta-ethnography as per the eMERGe guidance for data interpretation. RESULTS: Four studies were included. Two third-order constructs were generated through meta-ethnography: expectations of care and barriers to quality of care. We found that carers had expectations of care, and these could change over time. If discussion was not held with hospice staff early on, the carers could experience reduced care quality due to unmatched expectations. Unmatched expectations acted as barriers to care and these were found in terms of carers not feeling adequately supported, and/or having the person discharged from hospice, which would entail increased care responsibility for carers. CONCLUSION: In view of an increase in new dementia cases over time and with hospice services being under pressure, integrating palliative care services within community-based models of care is key to reducing the risk of having inadequate and under resourced services for people with dementia.
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Demência , Hospitais para Doentes Terminais , Assistência Terminal , Humanos , Cuidadores , Antropologia Cultural , Demência/terapiaRESUMO
OBJECTIVES: Carotid intima-media thickness (CIMT) is a noninvasive marker of atherosclerosis, a typical pathologic process underlying cardiovascular diseases (CVDs). It is essential to explore the relationships between weight loss and the reduction of CIMT. STUDY DESIGN: This was an updated systematic review and meta-analysis. METHODS: A systematic literature search was conducted to collect relevant clinical trials. The pooled results of meta-analyses were assessed by weighted mean difference (WMD) and the corresponding 95 % confidence interval (95% CI). RESULTS: Thirty-three articles involving 2273 participants were collected in this meta-analysis. Among all participants with obesity, the pooled mean of weight loss was -23.26 kg (95% CI: -27.71 to -18.81), and the pooled mean change of CIMT was -0.06 mm (95% CI: -0.08 to -0.04). Compared with Non-surgical interventions, Surgical ones could lead to much higher weight loss (Pbetween groups < 0.001). A more significant CIMT reduction was identified among Surgical intervention patients than among Non-surgical intervention participants (Pbetween groups < 0.001). CONCLUSIONS: Effective interventions, especially Surgical interventions, could reduce the weight of patients with obesity, followed by the decline of CIMT, which might further disturb atherosclerosis progression and lower CVD risk.
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Aterosclerose , Doenças Cardiovasculares , Humanos , Fatores de Risco , Espessura Intima-Media Carotídea , Obesidade/complicações , Redução de PesoRESUMO
BACKGROUND: Ovarian tissue cryopreservation for fertility preservation carries a risk of malignant cell re-seeding. Artificial ovary is a promising method to solve such a problem. However, ovary decellularization protocols are limited. Hence, further studies are necessary to get better ovarian decellularization techniques for the construction of artificial ovary scaffolds. OBJECTIVE: To establish an innovative decellularization technique for whole porcine ovaries by integrating liquid nitrogen with chemical agents to reduce the contact time between the scaffolds and chemical reagents. MATERIALS AND METHODS: Porcine ovaries were randomly assigned to three groups: novel decellularized group, conventional decellularized group and fresh group. The ovaries in the novel decellularized group underwent three cycles of freezing by liquid nitrogen and thawing at temperatures around 37 degree C before decellularization. The efficiency of the decellularization procedure was assessed through histological staining and DNA content analysis. The maintenance of ovarian decellularized extracellular matrix(ODECM) constituents was determined by analyzing the content of matrix proteins. Additionally, we evaluated the biocompatibility of the decellularized extracellular matrix(dECM) by observing the growth of granulosa cells on the ODECM scaffold in vitro. RESULTS: Hematoxylin and eosin staining, DAPI staining and DNA quantification techniques collectively confirm the success of the novel decellularization methods in removing cellular and nuclear components from ovarian tissue. Moreover, quantitative assessments of ODECM contents revealed that the novel decellularization technique preserved more collagen and glycosaminoglycan compared to the conventional decellularized group (P<0.05). Additionally, the novel decellularized scaffold exhibited a significantly higher number of granulosa cells than the conventional scaffold during in vitro co-culture (P<0.05). CONCLUSION: The novel decellularized method demonstrated high efficacy in eliminating DNA and cellular structures while effectively preserving the extracellular matrix. As a result, the novel decellularized method holds significant promise as a viable technique for ovarian decellularization in forthcoming studies. Doi.org/10.54680/fr24310110212.
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Criopreservação , Matriz Extracelular Descelularizada , Nitrogênio , Ovário , Alicerces Teciduais , Animais , Feminino , Nitrogênio/química , Suínos , Ovário/citologia , Alicerces Teciduais/química , Criopreservação/métodos , Matriz Extracelular Descelularizada/química , Engenharia Tecidual/métodos , Células da Granulosa/citologia , Preservação da Fertilidade/métodos , Matriz Extracelular/química , DNA/análise , DNA/químicaRESUMO
1. Melanin distribution typically exhibits a gradient dilution along the dorsal-ventral axis of the body, including in domestic geese. However, the specific genes and molecular mechanisms responsible for this melanin distribution pattern remain incompletely understood.2. The transcriptomic comparisons were conducted at three embryonic stages, specifically on embryonic d 15 (E15), 22 (E22), and 29 (E29), between the pigmented dorsal skin and the depigmented distal foot.3. Differentially expressed genes (DEGs) associated with melanin synthesis were identified, particularly TYR, TYRP1, and EDNRB2, which exhibited significantly higher expression levels in the dorsal skin at E15 and E22. However, expression levels significantly decreased in later stages (E29).4. The ASIP gene showed remarkably high-expression levels in the distal feet compared to the dorsal skin post-E22 stage (log2FC: 5.31/6.88 at E22/E29). Gene Ontology (GO) enrichment analysis detected eight terms associated with melanin synthesis and melanosome formation (p < 0.05), including melanosome membrane (GO: 0033162) and melanin biosynthetic process (GO: 0042438). Additionally, KEGG pathway analysis showed significant enrichment of the melanogenesis pathway (hsa004916) at d 22 (E22).