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1.
J Am Heart Assoc ; : e033295, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38979791

RESUMO

BACKGROUND: Cardiovascular disease and cancer share a common risk factor: chronic stress/allostatic load (AL). A 1-point increase in AL is linked to up to a 30% higher risk of major cardiac events (MACE) in patients with prostate cancer. However, AL's role in MACE in breast cancer, lung cancer, or colorectal cancer remains unknown. METHODS AND RESULTS: Patients ≥18 years of age diagnosed with the mentioned 3 cancers of interest (2010-2019) and followed up at a large, hybrid academic-community practice were included in this retrospective cohort study. AL was modeled as an ordinal measure (0-11). Adjusted Fine-Gray competing risks regressions estimated the impact of AL precancer diagnosis on 2-year MACE (a composite of heart failure, ischemic stroke, acute coronary syndrome, and atrial fibrillation). The effect of AL changes over time on MACE was calculated via piecewise Cox regression (before, and 2 months, 6 months, and 1 year after cancer diagnosis). Among 16 467 patients, 50.5% had breast cancer, 27.9% had lung cancer, and 21.4% had colorectal cancer. A 1-point elevation in AL before breast cancer diagnosis corresponded to a 10% heightened associated risk of MACE (adjusted hazard ratio, 1.10 [95% CI, 1.06-1.13]). Similar findings were noted in lung cancer (adjusted hazard ratio, 1.16 [95% CI, 1.12-1.20]) and colorectal cancer (adjusted hazard ratio, 1.13 [95% CI, 1.08-1.19]). When considering AL as a time-varying exposure, the peak associated MACE risk occurred with a 1-point AL rise between 6 and 12 months post- breast cancer, lung cancer, and colorectal cancer diagnosis. CONCLUSIONS: AL warrants investigation as a potential marker in these patients to identify those at elevated cardiovascular risk and intervene accordingly.

2.
Neurochem Res ; 49(8): 2197-2214, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38834846

RESUMO

Neuroinflammation and endothelial cell apoptosis are prominent features of blood-brain barrier (BBB) disruption, which have been described in Alzheimer's disease (AD) and can predict cognitive decline. Recent reports revealed vascular ß-amyloid (Aß) deposits, Muller cell degeneration and microglial dysfunction in the retina of AD patients. However, there has been no in-depth research on the roles of inflammation, retinal endothelial cell apoptosis, and blood-retinal barrier (BRB) damage in AD retinopathy. We found that Raddeanin A (RDA) could improve pathological and cognitive deficits in a mouse model of Alzheimer's disease by targeting ß-amyloidosis, However, the effects of RDA on AD retinal function require further study. To clarify whether RDA inhibits inflammation and apoptosis and thus improves BRB function in AD-related retinopathy. In vitro we used Aß-treated HRECs and MIO-M1 cells, and in vivo we used 3×Tg-AD mice to investigate the effect of RDA on BRB in AD-related retinopathy. We found that RDA could improve BRB function in AD-related retinopathy by inhibiting NLRP3-mediated inflammation and suppressing Wnt/ß-catenin pathway-mediated apoptosis, which is expected to improve the pathological changes in AD-related retinopathy and the quality of life of AD patients.


Assuntos
Doença de Alzheimer , Apoptose , Barreira Hematorretiniana , Camundongos Transgênicos , Retina , Animais , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Apoptose/efeitos dos fármacos , Barreira Hematorretiniana/efeitos dos fármacos , Barreira Hematorretiniana/metabolismo , Retina/efeitos dos fármacos , Retina/metabolismo , Retina/patologia , Camundongos , Inflamação/metabolismo , Inflamação/tratamento farmacológico , Camundongos Endogâmicos C57BL , Humanos , Peptídeos beta-Amiloides/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Via de Sinalização Wnt/efeitos dos fármacos , Via de Sinalização Wnt/fisiologia , Masculino
3.
Behav Ecol ; 35(4): arae044, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38903732

RESUMO

Males often strategically adjust the number of available sperm based on the social context (i.e. sperm priming response), but it remains unclear how environmental and genetic factors shape this adjustment. In freshwater ecosystems, high ambient temperatures often lead to isolated pools of hotter water in which inbreeding occurs. Higher water temperatures and inbreeding can impair fish development, potentially disrupting sperm production. We used guppies (Poecilia reticulata) to investigate how developmental temperature (26 °C, 30 °C) and male inbreeding status (inbred, outbred) influence their sperm priming response. We also tested if sperm priming was affected by whether the female was a relative (sister) and whether she was inbred or outbred. There was no effect of rearing temperature; male inbreeding status alone determined the number of available sperm in response to female presence, her inbreeding status, and her relatedness. Inbred males produced significantly more sperm in the presence of an unrelated, outbred female than when no female was present. Conversely, outbred males did not alter the number of sperm available in response to female presence or relatedness. Moreover, inbred males produced marginally more sperm when exposed to an unrelated female that was outbred rather than inbred, but there was no difference when exposed to an inbred female that was unrelated versus related. Together, a sperm priming response was only observed in inbred males when exposed to an outbred female. Outbred females in our study were larger than inbred females, suggesting that inbred males strategically allocated ejaculate resources toward females in better condition.

4.
AMIA Jt Summits Transl Sci Proc ; 2024: 478-487, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38827053

RESUMO

The emerging large language models (LLMs) are actively evaluated in various fields including healthcare. Most studies have focused on established benchmarks and standard parameters; however, the variation and impact of prompt engineering and fine-tuning strategies have not been fully explored. This study benchmarks GPT-3.5 Turbo, GPT-4, and Llama-7B against BERT models and medical fellows' annotations in identifying patients with metastatic cancer from discharge summaries. Results revealed that clear, concise prompts incorporating reasoning steps significantly enhanced performance. GPT-4 exhibited superior performance among all models. Notably, one-shot learning and fine-tuning provided no incremental benefit. The model's accuracy sustained even when keywords for metastatic cancer were removed or when half of the input tokens were randomly discarded. These findings underscore GPT-4's potential to substitute specialized models, such as PubMedBERT, through strategic prompt engineering, and suggest opportunities to improve open-source models, which are better suited to use in clinical settings.

5.
Ann Otol Rhinol Laryngol ; : 34894241261491, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38877731

RESUMO

OBJECTIVES: Pendred syndrome, an autosomal recessive disorder, is often associated with pathogenic variants of the SLC26A4 gene that encodes the pendrin protein. Given its autosomal recessive inheritance, tracing the family history and screening siblings become crucial once a diagnosis of Pendred syndrome is confirmed. This case report aims to underscore the variability in inner ear morphology within a family diagnosed with Pendred syndrome, all carrying the same SLC26A4 gene mutation. METHODS: A chart review and a review of the literature. RESULTS: We present a family of 4, all of whom possess sensorineural hearing loss due to the same homozygous SLC26A4 variant c.919-2A>G. Intriguingly, clinical manifestations, especially inner ear deformities, displayed variability among family members. Notably, 1 family member exhibited a normal cochleovestibular structure morphology, which was rarely reported in the literature. CONCLUSIONS: This report highlights the significance of genetic testing and familial consultation when a proband exhibits typical Pendred syndrome symptoms. It also underscores that the inner ear morphology can exhibit variability among family members, even with the same homozygous SLC26A4 variant.

6.
Harmful Algae ; 135: 102633, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38830715

RESUMO

Nitrogen-fixing cyanobacteria not only cause severe blooms but also play an important role in the nitrogen input processes of lakes. The production of extracellular polymeric substances (EPS) and the ability to fix nitrogen from the atmosphere provide nitrogen-fixing cyanobacteria with a competitive advantage over other organisms. Temperature and nitrogen availability are key environmental factors in regulating the growth of cyanobacteria. In this study, Dolichospermum (formerly known as Anabaena) was cultivated at three different temperatures (10 °C, 20 °C, and 30 °C) to examine the impact of temperature and nitrogen availability on nitrogen fixation capacity and the release of EPS. Initially, confocal laser scanning microscopy (CLSM) and the quantification of heterocysts at different temperatures revealed that lower temperatures (10 °C) hindered the differentiation of heterocysts under nitrogen-deprived conditions. Additionally, while heterocysts inhibited the photosynthetic activity of Dolichospermum, the secretion of EPS was notably affected by nitrogen limitation, particularly at 30 °C. Finally, real-time quantitative polymerase chain reaction (qPCR) was used to measure the expression of nitrogen-utilizing genes (ntcA and nifH) and EPS synthesis-related genes (wzb and wzc). The results indicated that under nitrogen-deprived conditions, the expression of each gene was upregulated, and there was a significant correlation between the upregulation of nitrogen-utilizing and EPS synthesis genes (P < 0.05). Our findings suggested that Dolichospermum responded to temperature variation by affecting the formation of heterocysts, impacting its potential nitrogen fixation capacity. Furthermore, the quantity of EPS released was more influenced by nitrogen availability than temperature. This research enhances our comprehension of interconnections between nitrogen deprivation and EPS production under the different temperatures.


Assuntos
Matriz Extracelular de Substâncias Poliméricas , Fixação de Nitrogênio , Nitrogênio , Temperatura , Nitrogênio/metabolismo , Matriz Extracelular de Substâncias Poliméricas/metabolismo , Anabaena/metabolismo , Anabaena/fisiologia , Anabaena/genética
7.
Acta Pharmacol Sin ; 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38862818

RESUMO

Diabetic cardiomyopathy (DCM) is a complication of diabetes mellitus characterized by heart failure and cardiac remodeling. Previous studies show that tetrahydroberberrubine (THBru) retrogrades cardiac aging by promoting PHB2-mediated mitochondrial autophagy and prevents peritoneal adhesion by suppressing inflammation. In this study we investigated whether THBru exerted protective effect against DCM in db/db mice and potential mechanisms. Eight-week-old male db/db mice were administered THBru (25, 50 mg·kg-1·d-1, i.g.) for 12 weeks. Cardiac function was assessed using echocardiography. We showed that THBru administration significantly improved both cardiac systolic and diastolic function, as well as attenuated cardiac remodeling in db/db mice. In primary neonatal mouse cardiomyocytes (NMCMs), THBru (20, 40 µM) dose-dependently ameliorated high glucose (HG)-induced cell damage, hypertrophy, inflammatory cytokines release, and reactive oxygen species (ROS) production. Using Autodock, surface plasmon resonance (SPR) and DARTS analyses, we revealed that THBru bound to the domain of the receptor for advanced glycosylation end products (RAGE), subsequently leading to inactivation of the PI3K/AKT/NF-κB pathway. Importantly, overexpression of RAGE in NMCMs reversed HG-induced inactivation of the PI3K/AKT/NF-κB pathway and subsequently counteracted the beneficial effects mediated by THBru. We conclude that THBru acts as an inhibitor of RAGE, leading to inactivation of the PI3K/AKT/NF-κB pathway. This action effectively alleviates the inflammatory responses and oxidative stress in cardiomyocytes, ultimately leading to ameliorated DCM.

8.
Behav Ecol ; 35(4): arae037, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38779595

RESUMO

Male-male contests for access to females or breeding resources are critical in determining male reproductive success. Larger males and those with more effective weaponry are more likely to win fights. However, even after controlling for such predictors of fighting ability, studies have reported a winner-loser effect: previous winners are more likely to win subsequent contests, while losers often suffer repeated defeats. While the effect of winning-losing is well-documented for the outcome of future fights, its effect on other behaviors (e.g. mating) remains poorly investigated. Here, we test whether a winning versus losing experience influenced subsequent behaviors of male mosquitofish (Gambusia holbrooki) toward rivals and potential mates. We housed focal males with either a smaller or larger opponent for 24 h to manipulate their fighting experience to become winners or losers, respectively. The focal males then underwent tests that required them to enter and swim through a narrow corridor to reach females, bypassing a cylinder that contained either a larger rival male (competitive scenario), a juvenile or was empty (non-competitive scenarios). The tests were repeated after 1 wk. Winners were more likely to leave the start area and to reach the females, but only when a larger rival was presented, indicating higher levels of risk-taking behavior in aggressive interactions. This winner-loser effect persisted for at least 1 wk. We suggest that male mosquitofish adjust their assessment of their own and/or their rival's fighting ability following contests in ways whose detection by researchers depends on the social context.

9.
PLoS One ; 19(5): e0296003, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38787854

RESUMO

Maintenance of the intestinal epithelium requires constant self-renewal and regeneration. Tight regulation of proliferation and differentiation of intestinal stem cells within the crypt region is critical to maintaining homeostasis. The transcriptional co-factors ß-catenin and YAP are required for proliferation during normal homeostasis as well as intestinal regeneration after injury: aberrant signaling activity results in over proliferation and tumorigenesis. Although both YAP and ß-catenin activity are controlled along canonical pathways, it is becoming increasingly clear that non-canonical regulation of these transcriptional regulators plays a role in fine tuning their activity. We have shown previously that MAMDC4 (Endotubin, AEGP), an integral membrane protein present in endosomes, regulates both YAP and ß-catenin activity in kidney epithelial cells and in the developing intestinal epithelium. Here we show that MAMDC4 interacts with members of the signalosome and mediates cross-talk between YAP and ß-catenin. Interestingly, this cross-talk occurs through a non-canonical pathway involving interactions between AMOT:YAP and AMOT:ß-catenin.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Endossomos , Fatores de Transcrição , Via de Sinalização Wnt , beta Catenina , Humanos , beta Catenina/metabolismo , Endossomos/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Animais , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas de Sinalização YAP/metabolismo , Fosfoproteínas/metabolismo , Fosfoproteínas/genética , Camundongos , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Células HEK293 , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Ligação Proteica
10.
World J Gastrointest Surg ; 16(5): 1385-1394, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38817293

RESUMO

BACKGROUND: Previous studies have validated the efficacy of both magnetic compression and surgical techniques in creating rabbit tracheoesophageal fistula (TEF) models. Magnetic compression achieves a 100% success rate but requires more time, while surgery, though less frequently successful, offers rapid model establishment and technical maturity in larger animal models. AIM: To determine the optimal approach for rabbit disease modeling and refine the process. METHODS: TEF models were created in 12 rabbits using both the modified magnetic compression technique and surgery. Comparisons of the time to model establishment, success rate, food and water intake, weight changes, activity levels, bronchoscopy findings, white blood cell counts, and biopsies were performed. In response to the failures encountered during modified magnetic compression modeling, we increased the sample size to 15 rabbit models and assessed the repeatability and stability of the models, comparing them with the original magnetic compression technique. RESULTS: The modified magnetic compression technique achieved a 66.7% success rate, whereas the success rate of the surgery technique was 33.3%. Surviving surgical rabbits might not meet subsequent experimental requirements due to TEF-related inflammation. In the modified magnetic compression group, one rabbit died, possibly due to magnet corrosion, and another died from tracheal magnet obstruction. Similar events occurred during the second round of modified magnetic compression modeling, with one rabbit possibly succumbing to aggravated lung infection. The operation time of the first round of modified magnetic compression was 3.2 ± 0.6 min, which was significantly reduced to 2.1 ± 0.4 min in the second round, compared to both the first round and that of the original technique. CONCLUSION: The modified magnetic compression technique exhibits lower stress responses, a simple procedure, a high success rate, and lower modeling costs, making it a more appropriate choice for constructing TEF models in rabbits.

12.
Arch Virol ; 169(5): 114, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38700535

RESUMO

OBJECTIVE: Epstein-Barr virus (EBV)-associated gastric cancer (EBVaGC) is a distinct molecular subtype of gastric cancer (GC). At present, the clinical characteristics and prognostic implications of EBV infection and the potential clinical benefits of immune checkpoint blockade in GC remain to be clarified. Hence, this study was designed to analyze the clinical and pathological characteristics of GC patients with varying EBV infection states and compare their overall survival (OS). METHODS: A retrospective study was performed on 1031 consecutive GC patients who underwent gastrectomy at the Affiliated Hospital of Xuzhou Medical University from February 2018 to November 2022. EBV-encoded RNA (EBER) in situ hybridization (ISH) was used for EBV assessment, and immunohistochemical staining was used for evaluation of human epidermal growth factor receptor 2 (HER2), programmed death ligand 1 (PD-L1), and Ki67 expression. EBVaGC was defined as tumors with EBV positivity. In addition, EBV-negative GC (EBVnGC) patients were matched with EBVaGC patients based on seven clinicopathological parameters (age, gender, anatomic subsite, tumor size, Lauren classification, degree of differentiation, and tumor-node-metastasis [TNM] stage). The correlations of clinical features with HER2, PD-L1, and Ki67 expression were evaluated statistically. The survival of patients was assessed through medical records, telephone, or WeChat communication, and prognostic analysis was performed using the logrank test as well as univariable and multivariable regression analysis. RESULTS: Out of 1031 GC patients tested, 35 (3.4%) were diagnosed with EBVaGC. Notably, the EBVaGC group exhibited a distinct predominance of males and younger patients, significantly higher Ki67 and PD-L1 expression levels, and a lower prevalence of pericancerous nerve invasion than the EBVnGC group (P < 0.01). In the 35 EBVaGC cases, Ki67 expression was negatively correlated with age (P < 0.05), suggesting that a younger onset age was associated with higher Ki67 expression. In addition, PD-L1 expression was correlated with the degree of differentiation, T-stage, and clinical stage of the patient. Furthermore, PD-L1 expression was elevated in tumors with lower differentiation or at later stages (P < 0.05). Using univariate analysis, Ki67, PD-L1, and clinical stage were identified as significant factors influencing the overall survival (OS) of EBVaGC patients (P < 0.05). Moreover, multivariate survival analysis revealed that clinical stage and Ki67 expression were independent risk factors for the OS of the patients (P < 0.05), and the three-year OS rate of EBVaGC patients was 64.2%. CONCLUSION: EBV-ISH is a practical and valuable method to identify EBVaGC. Owing to its unique etiological, pathological, and clinical characteristics, patients with EBVaGC might benefit from immune checkpoint blockade therapy.


Assuntos
Infecções por Vírus Epstein-Barr , Herpesvirus Humano 4 , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/virologia , Neoplasias Gástricas/patologia , Masculino , Feminino , Infecções por Vírus Epstein-Barr/virologia , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/mortalidade , Pessoa de Meia-Idade , Herpesvirus Humano 4/genética , Prognóstico , Estudos Retrospectivos , Idoso , Adulto , Antígeno B7-H1/metabolismo , Antígeno B7-H1/genética , Receptor ErbB-2/metabolismo , Receptor ErbB-2/genética , Antígeno Ki-67/metabolismo , RNA Viral/genética , Gastrectomia
13.
PLoS Biol ; 22(5): e3002519, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38787858

RESUMO

When males compete, sexual selection favors reproductive traits that increase their mating or fertilization success (pre- and postcopulatory sexual selection). It is assumed that males face a trade-off between these 2 types of sexual traits because they both draw from the same pool of resources. Consequently, allocation into mate acquisition or ejaculation should create similar trade-offs with other key life history traits. Tests of these assumptions are exceedingly rare. Males only ejaculate after they mate, and the costs of ejaculation are therefore highly confounded with those of mating effort. Consequently, little is known about how each component of reproductive allocation affects a male's future performance. Here, we ran an experiment using a novel technique to distinguish the life history costs of mating effort and ejaculation for mosquitofish (Gambusia holbrooki). We compared manipulated males (mate without ejaculation), control males (mate and ejaculate), and naïve males (neither mate nor ejaculate) continuously housed with a female and 2 rival males. We assessed their growth, somatic maintenance, mating and fighting behavior, and sperm traits after 8 and 16 weeks. Past mating effort significantly lowered a male's future mating effort and growth, but not his sperm production, while past sperm release significantly lowered a male's future ejaculate quantity, but not his mating effort. Immune response was the only trait impacted by both past mating effort and past ejaculation. These findings challenge the assumption that male reproductive allocation draws from a common pool of resources to generate similar life history costs later in life. Instead, we provide clear evidence that allocation into traits under pre- and postcopulatory sexual selection have different trait-specific effects on subsequent male reproductive performance.


Assuntos
Ejaculação , Reprodução , Comportamento Sexual Animal , Masculino , Animais , Ejaculação/fisiologia , Feminino , Comportamento Sexual Animal/fisiologia , Reprodução/fisiologia , Preferência de Acasalamento Animal/fisiologia , Espermatozoides/fisiologia , Seleção Sexual
14.
Inorg Chem ; 63(24): 10943-10948, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38818955

RESUMO

Investigating novel nonlinear optical (NLO) active units serves as a valuable method for broadening the research landscape of NLO materials. This study showcases the potential of the cytosinium cation (C4H6N3O)+ as a novel NLO-active motif through theoretical calculations. The title compound exhibited a wide band gap of 3.85 eV, along with a moderate second harmonic generation (SHG) response of 1.65 times that of KH2PO4 (KDP) and significant birefringence of 0.47. Its exceptional optical properties are primarily attributed to the synergy interaction between cations and anionic groups in the asymmetric unit.

15.
Pediatr Neurol ; 156: 59-65, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38733855

RESUMO

BACKGROUND: Bronchopulmonary dysplasia (BPD) affects the microstructure of white matter in preterm infants, but its influence on the changes of the brain structural network has not been elaborated. This study aims to investigate the connectivity characteristics of the brain structural network of BPD by using diffusion tensor imaging. METHODS: Thirty-three infants with BPD and 26 infants without BPD were enrolled in this study. Brain structural networks were constructed utilizing automated anatomic labeling mapping by tracing the fibers between each pair of regions in individual space. We calculated network metrics such as global efficiency, local efficiency, clustering coefficients, characteristic path length, and small-worldness. Then we compared the network metrics of these infants with those of 57 healthy term infants of comparable postmenstrual age at magnetic resonance imaging scan. Finally, network-based statistics was used to analyze the differences in brain network connectivity between the groups with and without BPD. RESULTS: Preterm infants with BPD had higher local efficiency and clustering coefficient, lower global efficiency, and longer characteristic path length. Also, preterm infants with BPD had decreased strength of limbic connections mainly in four brain regions: the left lingual gyrus, the left calcarine fissure and surrounding cortex, the right parahippocampal gyrus, and the left precuneus. CONCLUSIONS: Our findings suggest that preterm infants with BPD have lower network integration and higher segregation at term-equivalent age, which may reflect a compensatory mechanism. In addition, BPD affects brain regions involved in visual as well as cognitive functions; these findings provide a new approach to diagnose potential brain damage in preterm infants with BPD.


Assuntos
Encéfalo , Displasia Broncopulmonar , Imagem de Tensor de Difusão , Recém-Nascido Prematuro , Rede Nervosa , Humanos , Displasia Broncopulmonar/diagnóstico por imagem , Displasia Broncopulmonar/fisiopatologia , Masculino , Feminino , Recém-Nascido , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiopatologia , Rede Nervosa/patologia , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiopatologia , Imageamento por Ressonância Magnética
16.
Neural Netw ; 176: 106345, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38733798

RESUMO

Local Interpretability Model-agnostic Explanations (LIME) is a well-known post-hoc technique for explaining black-box models. While very useful, recent research highlights challenges around the explanations generated. In particular, there is a potential lack of stability, where the explanations provided vary over repeated runs of the algorithm, casting doubt on their reliability. This paper investigates the stability of LIME when applied to multivariate time series classification. We demonstrate that the traditional methods for generating neighbours used in LIME carry a high risk of creating 'fake' neighbours, which are out-of-distribution in respect to the trained model and far away from the input to be explained. This risk is particularly pronounced for time series data because of their substantial temporal dependencies. We discuss how these out-of-distribution neighbours contribute to unstable explanations. Furthermore, LIME weights neighbours based on user-defined hyperparameters which are problem-dependent and hard to tune. We show how unsuitable hyperparameters can impact the stability of explanations. We propose a two-fold approach to address these issues. First, a generative model is employed to approximate the distribution of the training data set, from which within-distribution samples and thus meaningful neighbours can be created for LIME. Second, an adaptive weighting method is designed in which the hyperparameters are easier to tune than those of the traditional method. Experiments on real-world data sets demonstrate the effectiveness of the proposed method in providing more stable explanations using the LIME framework. In addition, in-depth discussions are provided on the reasons behind these results.


Assuntos
Algoritmos , Fatores de Tempo , Redes Neurais de Computação
17.
Nat Commun ; 15(1): 4444, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38789421

RESUMO

Mitochondrial respiration is essential for the survival and function of T cells used in adoptive cellular therapies. However, strategies that specifically enhance mitochondrial respiration to promote T cell function remain limited. Here, we investigate methylation-controlled J protein (MCJ), an endogenous negative regulator of mitochondrial complex I expressed in CD8 cells, as a target for improving the efficacy of adoptive T cell therapies. We demonstrate that MCJ inhibits mitochondrial respiration in murine CD8+ CAR-T cells and that deletion of MCJ increases their in vitro and in vivo efficacy against murine B cell leukaemia. Similarly, MCJ deletion in ovalbumin (OVA)-specific CD8+ T cells also increases their efficacy against established OVA-expressing melanoma tumors in vivo. Furthermore, we show for the first time that MCJ is expressed in human CD8 cells and that the level of MCJ expression correlates with the functional activity of CD8+ CAR-T cells. Silencing MCJ expression in human CD8 CAR-T cells increases their mitochondrial metabolism and enhances their anti-tumor activity. Thus, targeting MCJ may represent a potential therapeutic strategy to increase mitochondrial metabolism and improve the efficacy of adoptive T cell therapies.


Assuntos
Linfócitos T CD8-Positivos , Imunoterapia Adotiva , Mitocôndrias , Animais , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Mitocôndrias/metabolismo , Humanos , Imunoterapia Adotiva/métodos , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Mitocondriais/metabolismo , Proteínas Mitocondriais/genética , Respiração Celular , Linhagem Celular Tumoral , Feminino , Ovalbumina/imunologia , Melanoma Experimental/imunologia , Melanoma Experimental/terapia
18.
Hum Vaccin Immunother ; 20(1): 2339922, 2024 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-38639480

RESUMO

The growing number of Mpox cases in China has posed a challenge to public health. The prevalence of men who have sex with men behaviors among students has been consistently increasing each year in China, accompanied by a high frequency of unprotected anal sex. As crowded places, schools are highly likely to cause an Mpox outbreak among students through long-term close contact. Understanding university students' perceptions about Mpox and willingness to vaccinate play a vital role in implementing preventive measures in schools. This study aimed to assess knowledge, concerns, and vaccine acceptance toward Mpox among university students in North and Northeast China. A cross-sectional study was conducted among 3831 university students from seven universities in North and Northeast China between September 10 and September 25, 2023. This study found a relative insufficiency in Mpox knowledge among university students (71.60%), with less than half expressing concern about the Mpox outbreak (39.57%), and the majority exhibiting a positive attitude to vaccination (76.30%). Multivariate regression analysis revealed that a good knowledge level was associated with age, study discipline, education level, and a high level of concern about Mpox. Male, elderly, or highly educated participants had a low level of concern about Mpox. Participants with a high level of knowledge toward Mpox were more likely to have the vaccination willingness. This study might help governments and schools to understand students' Mpox perceptions and vaccination intentions, enabling them to implement effective measures in addressing the issue of inadequate understanding regarding Mpox among university students.


Assuntos
Mpox , Minorias Sexuais e de Gênero , Vacinas , Idoso , Humanos , Masculino , Feminino , Estudos Transversais , Homossexualidade Masculina , Universidades , China
19.
J Mol Med (Berl) ; 102(6): 819-830, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38568327

RESUMO

We conducted a comprehensive metabolomic analysis of plasma samples obtained from pregnant women who displayed varying post-vaccination antibody titers after receiving mRNA-1273-SARS-CoV-2 vaccines. The study involved 62 pregnant women, all of whom had been vaccinated after reaching 24 weeks of gestation. To quantify post-vaccination plasma antibody titers, we employed binding antibody units (BAU) in accordance with the World Health Organization International Standard. Subsequently, we classified the study participants into three distinct BAU/mL categories: those with high titers (above 2000), medium titers (ranging from 1000 to 2000), and low titers (below 1000). Plasma metabolomic profiling was conducted using 1H nuclear magnetic resonance spectroscopy, and the obtained data were correlated with the categorized antibody titers. Notably, in pregnant women exhibiting elevated anti-SARS-CoV-2 antibody titers, reduced plasma concentrations of acetate and urea were observed. A significant negative correlation between these compounds and antibody titers was also evident. An analysis of metabolomics pathways revealed significant inverse associations between antibody titers and four distinct amino acid metabolic pathways: (1) biosynthesis of phenylalanine, tyrosine, and tryptophan; (2) biosynthesis of valine, leucine, and isoleucine; (3) phenylalanine metabolism; and (4) degradation of valine, leucine, and isoleucine. Additionally, an association between the synthesis and degradation pathways of ketone bodies was evident. In conclusion, we identified different metabolic pathways that underlie the diverse humoral responses triggered by COVID-19 mRNA vaccines during pregnancy. Our data hold significant implications for refining COVID-19 vaccination approaches in expectant mothers. KEY MESSAGES : Anti-SARS-CoV-2 antibody titers decline as the number of days since COVID-19 vaccination increases. Anti-SARS-CoV-2 antibody titers are inversely associated with acetate, a microbial-derived metabolite, and urea. Amino acid metabolism is significantly associated with SARS-CoV-2 antibody titers.


Assuntos
Acetatos , Anticorpos Antivirais , Vacinas contra COVID-19 , COVID-19 , Metabolômica , SARS-CoV-2 , Ureia , Vacinação , Humanos , Feminino , Gravidez , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , COVID-19/imunologia , COVID-19/prevenção & controle , COVID-19/sangue , Metabolômica/métodos , SARS-CoV-2/imunologia , Adulto , Ureia/sangue , Vacinas contra COVID-19/imunologia , Metaboloma , Vacina de mRNA-1273 contra 2019-nCoV
20.
Neurosci Bull ; 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38656419

RESUMO

The existence of neural stem cells (NSCs) in the adult mammalian nervous system, although small in number and restricted to the sub-ventricular zone of the lateral ventricles, the dentate gyrus of the hippocampus, and the olfactory epithelium, is a gift of evolution for the adaptive brain function which requires persistent plastic changes of these regions. It is known that most adult NSCs are latent, showing long cell cycles. In the past decade, the concept of quiescent NSCs (qNSCs) has been widely accepted by researchers in the field, and great progress has been made in the biology of qNSCs. Although the spontaneous neuronal regeneration derived from adult NSCs is not significant, understanding how the behaviors of qNSCs are regulated sheds light on stimulating endogenous NSC-based neuronal regeneration. In this review, we mainly focus on the recent progress of the developmental origin and regulatory mechanisms that maintain qNSCs under normal conditions, and that mobilize qNSCs under pathological conditions, hoping to give some insights for future study.

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