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1.
Biomater Sci ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38598178

RESUMO

Correction for 'Hybrid protein microspheres and their responsive release behaviors and inhibitory effects on melanin synthesis' by Ee Taek Hwang et al., Biomater. Sci., 2024, https://doi.org/10.1039/d4bm00106k.

2.
iScience ; 27(3): 109256, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38455976

RESUMO

To address the challenge of solid tumor targeting in CAR-T therapy, we utilized the A56 antigen, which is uniquely expressed on a diverse range of cancer cells following the systemic administration of an oncolytic vaccinia virus (OVV). Immunohistochemical assays precisely confirmed exclusive localization of A56 to tumor tissues. In vitro studies demonstrated a distinct superiority of A56-dependent CAR-T cytotoxicity across multiple cancer cell lines. Building on these in vitro observations, we strategically administered A56 CAR-T cells, OVV, and hydroxyurea (HU) combination in HCT-116 tumor-bearing non-obese diabetic/severe combined immunodeficiency (NOD/SCID) mice, leading to a significant reduction in tumor size and an extended time to progression. Consequently, A56-targeting combinatorial immunotherapy provides the benefit of reducing inadvertent CAR-T effects on normal cells while preserving its effectiveness against cancer cells. Furthermore, our approach of implanting A56 via OVV on tumors facilitates a wide therapeutic application of CAR-T cells across various solid tumors.

3.
Biomater Sci ; 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38517309

RESUMO

In this study, the formation of protein microspheres through lysosomal enzyme-assisted biomineralized crystallization was demonstrated. Spherical micro-sized hybrid CaCO3 constructs were synthesized and characterized using field-emission scanning electron microscopy equipped with energy-dispersive X-ray spectroscopy, X-ray diffraction, Fourier-transform infrared spectroscopy, and particle size analysis. Additionally, parameters such as the Brunauer-Emmett-Teller surface area and single-point total pore volume, and adsorption/desorption analysis were used to investigate the mesoporous properties, which are advantageous for lysosomal enzyme (LE) loading. A LE can be used as an organic template, not only as a morphological controller but also for entrapping LE during the crystallization pathway. The hybrid protein microspheres accommodated 2.3 mg of LE with a 57% encapsulation efficiency and 5.1 wt% loading. The peroxidase activity of the microspheres was calculated and found to be approximately 0.0238 mM-1 min-1. pH-responsive release of the LE from CaCO3 was observed, suggesting potential biomedical and cosmetic applications in acidic environments. The hybrid LE microsphere treatment significantly alleviated melanin production in a dose-dependent manner and further downregulated the mRNA expression of MITF, tyrosinase, TYRP-1, and TYRP-2. These results indicate skin-whitening effects by inhibiting melanin without inducing cytotoxicity. The data provide the first evidence of the potential use of a LE for obtaining hybrid minerals and the effectiveness of biomineralization-based sustainable delivery of enzyme-based vehicles based on organelle-extract-assisted biomineralization.

5.
BMB Rep ; 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38523371

RESUMO

Cancer progression is driven by genetic mutations, environmental factors, and intricate interactions within the tumor microenvironment (TME). The TME comprises of diverse cell types, such as cancer cells, immune cells, stromal cells, and neuronal cells. These cells mutually influence each other through various factors, including cytokines, vascular perfusion, and matrix stiffness. In the initial or developmental stage of cancer, neurotrophic factors such as nerve growth factor, brain-derived neurotrophic factor, and glial cell line-derived neurotrophic factor are associated with poor prognosis of various cancers by communicating with cancer cells, immune cells, and peripheral nerves within the TME. Over the past decade, research has been conducted to prevent cancer growth by controlling the activation of neurotrophic factors within tumors, exhibiting a novel attemt in cancer treatment with promising results. More recently, research focusing on controlling cancer growth through regulation of the autonomic nervous system, including the sympathetic and parasympathetic nervous systems, has gained significant attention. Sympathetic signaling predominantly promotes tumor progression, while the role of parasympathetic signaling varies among different cancer types. Neurotransmitters released from these signalings can directly or indirectly affect tumor cells or immune cells within the TME. Additionally, sensory nerve significantly promotes cancer progression. In the advanced stage of cancer, cancer-associated cachexia occurs, characterized by tissue wasting and reduced quality of life. This process involves the pathways via brainstem growth and differentiation factor 15-glial cell line-derived neurotrophic factor receptor alpha-like signaling and hypothalamic proopiomelanocortin neurons. Our review highlights the critical role of neurotrophic factors as well as central nervous system on the progression of cancer, offering promising avenues for targeted therapeutic strategies.

6.
Nat Commun ; 15(1): 2102, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38453901

RESUMO

Nicotinamide adenine dinucleotide (NAD)+ serves as a crucial coenzyme in numerous essential biological reactions, and its cellular availability relies on the activity of the nicotinamide phosphoribosyltransferase (NAMPT)-catalyzed salvage pathway. Here we show that treatment with saturated fatty acids activates the NAD+ salvage pathway in hypothalamic astrocytes. Furthermore, inhibition of this pathway mitigates hypothalamic inflammation and attenuates the development of obesity in male mice fed a high-fat diet (HFD). Mechanistically, CD38 functions downstream of the NAD+ salvage pathway in hypothalamic astrocytes burdened with excess fat. The activation of the astrocytic NAMPT-NAD+-CD38 axis in response to fat overload induces proinflammatory responses in the hypothalamus. It also leads to aberrantly activated basal Ca2+ signals and compromised Ca2+ responses to metabolic hormones such as insulin, leptin, and glucagon-like peptide 1, ultimately resulting in dysfunctional hypothalamic astrocytes. Our findings highlight the significant contribution of the hypothalamic astrocytic NAD+ salvage pathway, along with its downstream CD38, to HFD-induced obesity.


Assuntos
Gorduras na Dieta , NAD , Masculino , Camundongos , Animais , NAD/metabolismo , Gorduras na Dieta/metabolismo , Astrócitos/metabolismo , Obesidade/metabolismo , Hipotálamo/metabolismo , Citocinas/metabolismo
7.
Clin Cardiol ; 47(3): e24248, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38436204

RESUMO

BACKGROUND: Sodium-glucose co-transporter 2 (SGLT2) inhibitors have been demonstrated to decrease cardiovascular adverse events. However, there is little real-world clinical evidence regarding a direct comparison between dapagliflozin and empagliflozin in patients with diabetes mellitus (DM). HYPOTHESIS: A difference in the cardiovascular efficancy of dapagliflozin versus empagliflozin in DM patients was anticipated, aiming to guide the optimal choice of SGLT2 inhibitors based on cardiovascular outcomes. METHODS: From 2014 to 2020, a total of 1549 patients with DM who were prescribed SGLT2 inhibitors such as dapagliflozin or empagliflozin were retrospectively enrolled. We categorized the study population into two groups: dapagliflozin (n = 981) and empagliflozin group (n = 568). The primary endpoint was major adverse cardiovascular events (MACE), defined as a composite of all-cause death, myocardial infarction (MI), stroke, or hospitalization for heart failure (HF) over a 3-year period. RESULTS: Propensity-score matching was performed (537 patients in each group). The mean age and hemoglobin A1c were 58.2 ± 13.0 years and 8.4 ± 1.7%, respectively. There was no significant difference between the dapagliflozin and empagliflozin groups in the risk of MACE (3.7% vs. 4.8%, hazard ratio [HR], 1.31; 95% confidence interval [CI], 0.73-2.35; p = 0.349). Furthermore, there were no differences between the two groups in secondary endpoints including all-cause death, MI, stroke, and hospitalization for HF. Prior MI and history of HF were independent predictors of MACE. CONCLUSIONS: Dapagliflozin and empagliflozin showed no significant difference of real-world clinical cardiovascular outcomes in patients with DM over a 3-year period. Further large randomized clinical trials will be warranted for better evaluation.


Assuntos
Compostos Benzidrílicos , Diabetes Mellitus , Glucosídeos , Insuficiência Cardíaca , Infarto do Miocárdio , Inibidores do Transportador 2 de Sódio-Glicose , Acidente Vascular Cerebral , Humanos , Estudos Retrospectivos , Inibidores do Transportador 2 de Sódio-Glicose/efeitos adversos , Insuficiência Cardíaca/epidemiologia
8.
JAMA Intern Med ; 184(3): 326-327, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38315468

RESUMO

This case report describes a patient in their 70s with hypertension and heart failure presenting to the emergency department with chest discomfort, nausea, anorexia, and weakness.


Assuntos
Digoxina , Insuficiência Cardíaca , Humanos , Digoxina/efeitos adversos , Cardiotônicos/efeitos adversos , Insuficiência Cardíaca/induzido quimicamente , Insuficiência Cardíaca/tratamento farmacológico
9.
Endocrinol Metab (Seoul) ; 39(1): 1-11, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38356211

RESUMO

5´-Adenosine monophosphate (AMP)-activated protein kinase (AMPK), a cellular energy sensor, is an essential enzyme that helps cells maintain stable energy levels during metabolic stress. The hypothalamus is pivotal in regulating energy balance within the body. Certain neurons in the hypothalamus are sensitive to fluctuations in food availability and energy stores, triggering adaptive responses to preserve systemic energy equilibrium. AMPK, expressed in these hypothalamic neurons, is instrumental in these regulatory processes. Hypothalamic AMPK activity is modulated by key metabolic hormones. Anorexigenic hormones, including leptin, insulin, and glucagon-like peptide 1, suppress hypothalamic AMPK activity, whereas the hunger hormone ghrelin activates it. These hormonal influences on hypothalamic AMPK activity are central to their roles in controlling food consumption and energy expenditure. Additionally, hypothalamic AMPK activity responds to variations in glucose concentrations. It becomes active during hypoglycemia but is deactivated when glucose is introduced directly into the hypothalamus. These shifts in AMPK activity within hypothalamic neurons are critical for maintaining glucose balance. Considering the vital function of hypothalamic AMPK in the regulation of overall energy and glucose balance, developing chemical agents that target the hypothalamus to modulate AMPK activity presents a promising therapeutic approach for metabolic conditions such as obesity and type 2 diabetes mellitus.


Assuntos
Proteínas Quinases Ativadas por AMP , Diabetes Mellitus Tipo 2 , Humanos , Proteínas Quinases Ativadas por AMP/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Hipotálamo/metabolismo , Insulina/metabolismo , Glucose
10.
Sci Adv ; 10(9): eadm7605, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38416820

RESUMO

Cerebral perfusion is critical for the early detection of neurological diseases and for effectively monitoring disease progression and treatment responses. Mouse models are widely used in brain research, often under anesthesia, which can affect vascular physiology. However, the impact of anesthesia on regional cerebral blood volume and flow in mice has not been thoroughly investigated. In this study, we have developed a whole-brain perfusion MRI approach by using a 5-second nitrogen gas stimulus under inhalational anesthetics to induce transient BOLD dynamic susceptibility contrast (DSC). This method proved to be highly sensitive, repeatable within each imaging session, and across four weekly sessions. Relative cerebral blood volumes measured by BOLD DSC agree well with those by contrast agents. Quantitative cerebral blood volume and flow metrics were successfully measured in mice under dexmedetomidine and various isoflurane doses using both total vasculature-sensitive gradient-echo and microvasculature-sensitive spin-echo BOLD MRI. Dexmedetomidine reduces cerebral perfusion, while isoflurane increases cerebral perfusion in a dose-dependent manner.


Assuntos
Anestesia , Dexmedetomidina , Isoflurano , Animais , Camundongos , Isoflurano/farmacologia , Dexmedetomidina/farmacologia , Imageamento por Ressonância Magnética/métodos , Hipóxia , Encéfalo/irrigação sanguínea , Perfusão , Circulação Cerebrovascular/fisiologia
11.
Am J Cardiol ; 213: 20-27, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38103764

RESUMO

There are little direct comparative evidences of strategies between ≥50% and the absolute target goal of low-density lipoprotein cholesterol (LDL-C) level <55 mg/100 ml for the patients who underwent percutaneous coronary intervention (PCI). This study aimed to investigate the clinical impact of different strategies between 2 groups of patients who underwent PCI. A total of 3,104 patients with previous PCI were retrospectively enrolled from 2014 to 2020 at Yeungnam University Medical Center. The study population was stratified into 2 groups based on whether the LDL-C level was <55 mg/100 ml at the 1-year mark or not. Furthermore, the 50% reduction rate of LDL-C was also categorized based on whether it had decreased by ≥50% from the initial LDL-C level at the 1-year mark. The primary end point was 3-year major adverse cardiovascular events (MACEs) which were defined as a composite of cardiovascular death, nonfatal myocardial infarction, target lesion revascularization, hospitalization for heart failure, or nonfatal stroke. There was no significant difference between the LDL <55 mg/100 ml group and the LDL ≥55 mg/100 ml group in the risk of MACEs (hazard ratio 1.06, 95% confidence interval 0.81 to 1.38, p = 0.690) after propensity score matching. However, the group that achieved ≥50% reduction of LDL-C from baseline LDL-C level showed a significant reduction in the occurrence of MACEs in the subgroup of LDL-C level ≥55 mg/100 ml (hazard ratio 0.41, 95% confidence interval 0.19 to 0.89, p = 0.025) compared with the group with <50% reduction of LDL-C. In all patients, the achievement rate of target LDL-C <55 mg/100 ml and more than 50% reduction from baseline was 17.2%. In conclusion, guideline-directed management strategy of ≥50% reduction of LDL-C from the baseline will be needed to reduce the incidence of MACEs in patients with LDL-C ≥55 mg/100 ml who underwent PCI. Additional efforts to increase the target goal achievement rate of LDL-C are warranted.


Assuntos
Infarto do Miocárdio , Intervenção Coronária Percutânea , Humanos , LDL-Colesterol , Estudos Retrospectivos , Infarto do Miocárdio/epidemiologia , Fatores de Risco , Resultado do Tratamento
12.
Circulation ; 148(23): 1907-1910, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38048393
13.
Heart Rhythm ; 20(12): 1789-1790, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38040482
16.
Mol Cells ; 46(11): 672-674, 2023 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-37968981
18.
Heliyon ; 9(10): e20925, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37867802

RESUMO

In this research, the geyser phenomenon occurring in a small-diameter two-phase closed thermosyphon (TPCT) was observed and the instability of the device was discussed. Geyser phenomena interfere with the natural circulation of internal working fluids, increasing the thermal resistance of the system and contributing to the instability of the device. This study attempts to improve the thermal performance and stability of the system using cellulose nanofiber (CNF) fluid as the working fluid. The use of CNF fluid was observed to reduce the magnitude of temperature change inside the evaporator of the TPCT significantly. Moreover, it improved the local boiling heat transfer coefficient by 3.1 %, 87.3 %, and 181.2 % on average when the filling ratios are 0.25, 0.5, and 0.75, respectively. Studying the local heat transfer performance and instability will be helpful in designing a more stable TPCT efficiently. Additionally, the findings of this study can be applied to solar thermal power generation or heat pipe research for cooling strategies in computing servers, depending on the input heat load.

19.
BMB Rep ; 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37817436

RESUMO

The stomach has emerged as a crucial endocrine organ in the regulation of feeding since the discovery of ghrelin. Gut-derived hormones, such as ghrelin and cholecystokinin, can act through the vagus nerve. We previously reported the satiety effect of hypothalamic clusterin, but the impact of peripheral clusterin remains unknown. In this study, we administered clusterin intraperitoneally to mice and observed its ability to suppress fasting-driven food intake. Interestingly, we found its synergism with cholecystokinin and antagonism with ghrelin. These effects were accompanied by increased c-fos immunoreactivity in nucleus tractus solitarius, area postrema, and hypothalamic paraventricular nucleus. Notably, truncal vagotomy abolished this response. The stomach expressed clusterin at high levels among the organs, and gastric clusterin was detected in specific enteroendocrine cells and the submucosal plexus. Gastric clusterin expression decreased after fasting but recovered after 2 hours of refeeding. Furthermore, we confirmed that stomachspecific overexpression of clusterin reduced food intake after overnight fasting. These results suggest that gastric clusterin may function as a gut-derived peptide involved in the regulation of feeding through the gut-brain axis.

20.
Heart Rhythm ; 20(10): 1414-1415, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37777302
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