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1.
Discov Oncol ; 15(1): 288, 2024 Jul 17.
Article de Anglais | MEDLINE | ID: mdl-39017974

RÉSUMÉ

PURPOSE: This research aimed to clarify the impact of residual ductal carcinoma in situ(DCIS) in surgical specimens obtained after neoadjuvant chemotherapy(NAC) for breast cancer on the associated prognosis outcomes. METHODS: This retrospective study was performed on a cohort of 1,009 patients who achieved pCR following NAC for breast cancer and underwent subsequent breast surgery at a single institution between January 2008 and December 2019. Overall survival, local recurrence-free survival, distant metastasis-free survival, and disease-free survival of the residual and non-residual DCIS groups were the outcomes compared, with further subgroup analysis performed according to hormone receptor status. RESULTS: 260 individuals (25.8%) presented with residual DCIS. Based on a median follow-up of 54.0 months, no significant differences in outcomes were observed between the two groups. Patients with residual DCIS and hormone receptor-negative (HR-) breast cancer demonstrated a significant decrease in distant metastasis-free survival (p = 0.030) compared to those without residual DCIS. In the HR + cohort, no significant difference was observed between the two groups. Multivariate analysis of the HR- cohort demonstrated a significant association between residual DCIS and an elevated risk for distant recurrence (hazard ratio = 2.3, 95% confidence interval = 1.01-5.20, p = 0.047). CONCLUSIONS: Residual DCIS following NAC may impact breast cancer outcomes, particularly with respect to the occurrence of distant metastasis in HR- patients. Therefore, clinicians must vigilantly monitor patients with residual DCIS after NAC, and further research is needed to expand our understanding of the clinical implications of residual DCIS.

2.
Diagnostics (Basel) ; 14(6)2024 Mar 11.
Article de Anglais | MEDLINE | ID: mdl-38535013

RÉSUMÉ

BACKGROUND: Few studies have evaluated digital morphology (DM) analyzers on body fluids (BF). We evaluated the performance of a DM analyzer, Sysmex DI-60 (Sysmex, Kobe, Japan) for white blood cell (WBC) differentials in BF samples. METHODS: In five BF samples (two pleural fluids and three ascites) containing a single, dominant cell type (>80%, neutrophils, lymphocytes, macrophages, abnormal lymphocytes, and malignant cells in each sample), we evaluated the precision of the DI-60 and compared the WBC differentials and turnaround times (TAT) between DI-60 and manual counting. RESULTS: The precision of the DI-60 pre-classification and verification was excellent (%CV, 0.01-3.16%). After verification, the DI-60 showed high sensitivity, specificity, and efficiency (ranges: 90.8-98.1%, 96.8-97.9%, and 92.5-98.0%, respectively) for the dominant cell types in neutrophil- and lymphocyte-dominant samples. For all samples, the DI-60 and manual counting showed high correlations for major cell types (neutrophils, lymphocytes, macrophages, and others, r = 0.72 to 0.94) after verification. The agreement between the pre-classification and verification of the DI-60 was strong in the neutrophil-dominant sample (κ = 0.81). The DI-60 showed a significantly longer TAT (min: s) than manual counting for all samples (median TAT/slide: 6:28 vs. 1:53, p < 0.0001), with remarkable differences in abnormal lymphocyte- and malignant cell-dominant samples (21:05 vs. 2:06; 12:34 vs. 2:25). CONCLUSIONS: The DI-60 may provide reliable data in neutrophil- and lymphocyte-dominant BF samples. However, it may require longer times and higher workloads for WBC differentials especially in BF samples containing atypical cells. Further improvement would be needed before applying DM analyzers for routine clinical practice in BF analysis.

3.
Diagnostics (Basel) ; 14(2)2024 Jan 22.
Article de Anglais | MEDLINE | ID: mdl-38275478

RÉSUMÉ

We evaluated the diagnostic performance of the STANDARD i-Q COVID-19 Ag Test, which was developed to detect viral antigens, using nasal and oral swabs. Sixty positive and 100 negative samples were analyzed. We determined the distribution of the Ct values according to the day of sample collection after symptom onset, the diagnostic performance of the total samples and subgroups separated by Ct value or time of sample collection, and the Ct value at which maximal accuracy was expected. No differences were observed in Ct values, except for the samples obtained on the day of symptom onset. The diagnostic sensitivity and specificity of the oral swabs were 75.0 and 100.0%, respectively, whereas those of the nasal swabs were 85.0 and 98.0%, respectively. The sensitivity was higher in samples with a high viral load collected earlier than those collected later, although the difference was not significant. False-negative results were confirmed in all samples with a Ct value ≥ 30.0. These results indicate that tests using oral and nasal swabs are helpful for diagnosing acute symptomatic cases with suspected high viral loads. Our tests exhibited relatively low sensitivity but high specificity rates, indicating the need to assess negative antigen test results.

4.
J Thromb Haemost ; 22(3): 834-850, 2024 Mar.
Article de Anglais | MEDLINE | ID: mdl-38072375

RÉSUMÉ

BACKGROUND: Platelets are generated from megakaryocytes (MKs), mainly located in the bone marrow (BM). Megakaryopoiesis can be affected by genetic disorders, metabolic diseases, and aging. The molecular mechanisms underlying platelet count regulation have not been fully elucidated. OBJECTIVES: In the present study, we investigated the role of thioredoxin-interacting protein (TXNIP), a protein that regulates cellular metabolism in megakaryopoiesis, using a Txnip-/- mouse model. METHODS: Wild-type (WT) and Txnip-/- mice (2-27-month-old) were studied. BM-derived MKs were analyzed to investigate the role of TXNIP in megakaryopoiesis with age. The global transcriptome of BM-derived CD41+ megakaryocyte precursors (MkPs) of WT and Txnip-/- mice were compared. The CD34+ hematopoietic stem cells isolated from human cord blood were differentiated into MKs. RESULTS: Txnip-/- mice developed thrombocytopenia at 4 to 5 months that worsened with age. During ex vivo megakaryopoiesis, Txnip-/- MkPs remained small, with decreased levels of MK-specific markers. Critically, Txnip-/- MkPs exhibited reduced mitochondrial reactive oxygen species, which was related to AKT activity. Txnip-/- MkPs also showed elevated glycolysis alongside increased glucose uptake for ATP production. Total RNA sequencing revealed enrichment for oxidative stress- and apoptosis-related genes in differentially expressed genes between Txnip-/- and WT MkPs. The effects of TXNIP on MKs were recapitulated during the differentiation of human cord blood-derived CD34+ hematopoietic stem cells. CONCLUSION: We provide evidence that the megakaryopoiesis pathway becomes exhausted with age in Txnip-/- mice with a decrease in terminal, mature MKs that response to thrombocytopenic challenge. Overall, this study demonstrates the role of TXNIP in megakaryopoiesis, regulating mitochondrial metabolism.


Sujet(s)
Mégacaryocytes , Thrombopénie , Animaux , Souris , Antigènes CD34/métabolisme , Plaquettes/métabolisme , Mégacaryocytes/métabolisme , Stress oxydatif , Thiorédoxines/génétique , Thiorédoxines/métabolisme , Thrombopénie/métabolisme
5.
Front Immunol ; 14: 1192907, 2023.
Article de Anglais | MEDLINE | ID: mdl-37539051

RÉSUMÉ

Gene-engineered immune cell therapies have partially transformed cancer treatment, as exemplified by the use of chimeric antigen receptor (CAR)-T cells in certain hematologic malignancies. However, there are several limitations that need to be addressed to target more cancer types. Natural killer (NK) cells are a type of innate immune cells that represent a unique biology in cancer immune surveillance. In particular, NK cells obtained from heathy donors can serve as a source for genetically engineered immune cell therapies. Therefore, NK-based therapies, including NK cells, CAR-NK cells, and antibodies that induce antibody-dependent cellular cytotoxicity of NK cells, have emerged. With recent advances in genetic engineering and cell biology techniques, NK cell-based therapies have become promising approaches for a wide range of cancers, viral infections, and senescence. This review provides a brief overview of NK cell characteristics and summarizes diseases that could benefit from NK-based therapies. In addition, we discuss recent preclinical and clinical investigations on the use of adoptive NK cell transfer and agents that can modulate NK cell activity.


Sujet(s)
Cellules tueuses naturelles , Tumeurs , Humains , Immunothérapie adoptive/méthodes , Immunothérapie/méthodes , Thérapie génétique
7.
J Microbiol Biotechnol ; 33(4): 500-510, 2023 Apr 28.
Article de Anglais | MEDLINE | ID: mdl-36746921

RÉSUMÉ

In this study, lactic acid bacteria were isolated from 21 top-selling probiotic products on Korean market and their antimicrobial resistance were analyzed. A total 152 strains were claimed to be contained in these products and 70 isolates belonging to three genera (Bifidobacterium, Lactobacillus, and Lactococcus) were obtained from these products. RAPD-PCR showed diversity among isolates of the same species except for two isolates of Lacticaibacillus rhamnosus from two different products. The agar dilution method and the broth dilution method produced different MICs for several antimicrobials. With the agar dilution method, five isolates (three isolates of Bifidobacterium animalis subsp. lactis, one isolate of B. breve, one isolate of B. longum) were susceptible to all nine antimicrobials and 15 isolates were multi-drug resistant. With the broth microdilution method, only two isolates (one isolate of B. breve and one isolate of B. longum) were susceptible while 16 isolates were multi-drug resistant. In this study, only two AMR genes were detected: 1) lnu(A) in one isolate of clindamycin-susceptible and lincomycin-resistant Limosilactobacillus reuteri; and 2) tet(W) in one tetracycline-susceptible isolate of B. longum B1-1 and two tetracycline-susceptible isolates and three tetracycline resistant isolates of B. animalis subsp. lactis. Transfer of these two genes via conjugation with a filter mating technique was not observed. These results suggest a need to monitor antimicrobial resistance in newly registered probiotics as well as probiotics with a long history of use.


Sujet(s)
Anti-infectieux , Bifidobacterium animalis , Lactobacillales , Probiotiques , Antibactériens/pharmacologie , Lactobacillales/génétique , Résistance bactérienne aux médicaments , Technique RAPD , Agar-agar , Tétracycline/pharmacologie , Tests de sensibilité microbienne , République de Corée
8.
Brain Stimul ; 16(2): 540-552, 2023.
Article de Anglais | MEDLINE | ID: mdl-36731773

RÉSUMÉ

BACKGROUND: Focused ultrasound stimulation (FUS) has the potential to provide non-invasive neuromodulation of deep brain regions with unparalleled spatial precision. However, the cellular and molecular consequences of ultrasound stimulation on neurons remains poorly understood. We previously reported that ultrasound stimulation induces increases in neuronal excitability that persist for hours following stimulation in vitro. In the present study we sought to further elucidate the molecular mechanisms by which ultrasound regulates neuronal excitability and synaptic function. OBJECTIVES: To determine the effect of ultrasound stimulation on voltage-gated ion channel function and synaptic plasticity. METHODS: Primary rat cortical neurons were exposed to a 40 s, 200 kHz pulsed ultrasound stimulus or sham-stimulus. Whole-cell patch clamp electrophysiology, quantitative proteomics and high-resolution confocal microscopy were employed to determine the effects of ultrasound stimulation on molecular regulators of neuronal excitability and synaptic function. RESULTS: We find that ultrasound exposure elicits sustained but reversible increases in whole-cell potassium currents. In addition, we find that ultrasound exposure activates synaptic signalling cascades that result in marked increases in excitatory synaptic transmission. Finally, we demonstrate the requirement of ionotropic glutamate receptor (AMPAR/NMDAR) activation for ultrasound-induced modulation of neuronal potassium currents. CONCLUSION: These results suggest specific patterns of pulsed ultrasound can induce contemporaneous enhancement of both neuronal excitability and synaptic function, with implications for the application of FUS in experimental and therapeutic settings. Further study is now required to deduce the precise molecular mechanisms through which these changes occur.


Sujet(s)
Potassium , Récepteurs ionotropes du glutamate , Rats , Animaux , Potassium/métabolisme , Potassium/pharmacologie , Rat Sprague-Dawley , Neurones/physiologie , Transmission synaptique/physiologie , Plasticité neuronale
9.
J Ethnopharmacol ; 290: 115096, 2022 May 23.
Article de Anglais | MEDLINE | ID: mdl-35182666

RÉSUMÉ

ETHNOPHARMACOLOGICAL RELEVANCE: Aloe vera (L.) Burm. f. (Liliaceae family) is a well-known traditional medicinal plant, that has been used to treat a variety of illnesses, for decades ranging from cancer to skin disorders including wounds. It has been included in the traditional and herbal healthcare systems of many cultures around the world, as well as the pharmacopeia of different countries. Several in vitro and in vivo studies have also confirmed its potential antioxidant, anti-inflammatory, and wound-healing activities, etc. in the consistency of its historical and traditional uses. However, most studies to date are based on the A. vera gel and latex including its wound-healing effects. Very few studies have been focused on its flower, and rarely with its effects on cutaneous wound healing and its molecular mechanism. AIM OF THE STUDY: To the best of our knowledge, this is the first study to report on the synergistic effect of the A. vera flower (AVF) and Aloe gel (PAG) on cutaneous wound-healing, as well as revealing its molecular mechanism targeting microfibril-associated glycoprotein 4 (MFAP4) and its associated signaling pathway. METHODS: To investigate the synergistic effect of A. vera flower and Aloe gel in cutaneous wound healing, cell viability, and cell migration, as well proliferation assay was performed. This was followed by quantitative real-time polymerase chain reaction and Western blot analyses in wounded conditions to check the effects of this mixture on protein and mRNA levels in normal human dermal fibroblast (NHDF) cells. Moreover, small interfering RNA (siRNA) -mediated knockdown of MFAP4 in NHDF cells was performed followed by migration assay and cell cycle analysis, to confirm its role in cutaneous wound healing. Additionally, HaCaT cells were included in this study to evaluate its migratory and anti-inflammatory effects. RESULTS: Based on our obtained results, the PAG and AVF mixture synergistically induced the proliferation, migration, and especially ECM formation of NHDF cells by enhancing the expression of MFAP4. Other extracellular components associated with MFAP4 signaling pathway, such as fibrillin, collagen, elastin, TGF ß, and α-SMA, also increased at both the protein and mRNA levels. Subsequently, this mixture initiated the phosphorylation of the extracellular signal-regulated kinase (ERK) and AKT signaling pathways, and the S-phase of the cell cycle was also slightly modified. Also, the mixture induced the migration of HaCaT cells along with the suppression of inflammatory cytokines. Moreover, the siRNA-mediated knockdown highlighted the crucial role of MFAP4 in cutaneous wound healing in NHDF cells. CONCLUSION: This study showed that the mixture of PAG and AVF has significant wound healing effects targeting MFAP4 and its associated signaling pathway. Additionally, MFAP4 was recognized as a new potential biomarker of wound healing, which can be confirmed by further in vivo studies.


Sujet(s)
Aloe , Fleurs , Gels/pharmacologie , Cicatrisation de plaie/effets des médicaments et des substances chimiques , Mouvement cellulaire/effets des médicaments et des substances chimiques , Survie cellulaire/effets des médicaments et des substances chimiques , Association thérapeutique , Cytokines/effets des médicaments et des substances chimiques , Relation dose-effet des médicaments , Synergie des médicaments , Extracellular Signal-Regulated MAP Kinases/effets des médicaments et des substances chimiques , Cellules HaCaT , Humains , Plantes médicinales , Protéines proto-oncogènes c-akt/effets des médicaments et des substances chimiques , Facteurs d'épissage des ARN/effets des médicaments et des substances chimiques , Petit ARN interférent , Transduction du signal/effets des médicaments et des substances chimiques , Peau/effets des médicaments et des substances chimiques
10.
Nat Commun ; 13(1): 27, 2022 01 14.
Article de Anglais | MEDLINE | ID: mdl-35031607

RÉSUMÉ

Coordinated programs of gene expression drive brain development. It is unclear which transcriptional programs, in which cell-types, are affected in neuropsychiatric disorders such as schizophrenia. Here we integrate human genetics with transcriptomic data from differentiation of human embryonic stem cells into cortical excitatory neurons. We identify transcriptional programs expressed during early neurogenesis in vitro and in human foetal cortex that are down-regulated in DLG2-/- lines. Down-regulation impacted neuronal differentiation and maturation, impairing migration, morphology and action potential generation. Genetic variation in these programs is associated with neuropsychiatric disorders and cognitive function, with associated variants predominantly concentrated in loss-of-function intolerant genes. Neurogenic programs also overlap schizophrenia GWAS enrichment previously identified in mature excitatory neurons, suggesting that pathways active during prenatal cortical development may also be associated with mature neuronal dysfunction. Our data from human embryonic stem cells, when combined with analysis of available foetal cortical gene expression data, de novo rare variants and GWAS statistics for neuropsychiatric disorders and cognition, reveal a convergence on transcriptional programs regulating excitatory cortical neurogenesis.


Sujet(s)
Cortex cérébral/embryologie , Régulation de l'expression des gènes au cours du développement , Guanylate kinase/génétique , Neurogenèse , Protéines suppresseurs de tumeurs/génétique , Animaux , Différenciation cellulaire , Cortex cérébral/cytologie , Cortex cérébral/métabolisme , Femelle , Techniques de knock-down de gènes , Prédisposition génétique à une maladie , Guanylate kinase/métabolisme , Cellules souches embryonnaires humaines/métabolisme , Humains , Troubles mentaux/génétique , Neurogenèse/génétique , Neurogenèse/physiologie , Neurones , Grossesse , Schizophrénie/génétique , Transcriptome , Protéines suppresseurs de tumeurs/métabolisme
11.
Int J Mol Sci ; 22(12)2021 Jun 17.
Article de Anglais | MEDLINE | ID: mdl-34204534

RÉSUMÉ

Leaky gut is a condition of increased paracellular permeability of the intestine due to compromised tight junction barriers. In recent years, this affliction has drawn the attention of scientists from different fields, as a myriad of studies prosecuted it to be the silent culprit of various immune diseases. Due to various controversies surrounding its culpability in the clinic, approaches to leaky gut are restricted in maintaining a healthy lifestyle, avoiding irritating factors, and practicing alternative medicine, including the consumption of supplements. In the current study, we investigate the tight junction-modulating effects of processed Aloe vera gel (PAG), comprising 5-400-kD polysaccharides as the main components. Our results show that oral treatment of 143 mg/kg PAG daily for 10 days improves the age-related leaky gut condition in old mice, by reducing their individual urinal lactulose/mannitol (L/M) ratio. In concordance with in vivo experiments, PAG treatment at dose 400 µg/mL accelerated the polarization process of Caco-2 monolayers. The underlying mechanism was attributed to enhancement in the expression of intestinal tight junction-associated scaffold protein zonula occludens (ZO)-1 at the translation level. This was induced by activation of the MAPK/ERK signaling pathway, which inhibits the translation repressor 4E-BP1. In conclusion, we propose that consuming PAG as a complementary food has the potential to benefit high-risk patients.


Sujet(s)
Muqueuse intestinale/effets des médicaments et des substances chimiques , Muqueuse intestinale/métabolisme , Préparations à base de plantes/pharmacologie , Jonctions serrées/effets des médicaments et des substances chimiques , Jonctions serrées/métabolisme , Animaux , Marqueurs biologiques , Lignée cellulaire , Perméabilité des membranes cellulaires , Cellules épithéliales/effets des médicaments et des substances chimiques , Cellules épithéliales/métabolisme , Femelle , Humains , Mâle , Souris , Modèles biologiques , Transduction du signal , Protéines de la jonction serrée/génétique , Protéines de la jonction serrée/métabolisme
12.
Article de Anglais | MEDLINE | ID: mdl-33936244

RÉSUMÉ

Venous insufficiency results from several factors responsible for the progression of inflammation and oxidative damage of veins. Recently, natural extracts have been proposed for the treatment of venous insufficiency, but their efficacies have not been fully elucidated. In the present study, we evaluate the combinatorial effects on anti-inflammatory and anti-vascular leakage potential of mixed compositions containing different proportions of Centella asiatica extract (CE) and Vitis vinifera L. leaf extract (VVE) using an inflammation model of lipopolysaccharide- (LPS-) stimulated RAW264.7 cells and various vascular permeability models in mice (acetic-acid-induced peritoneal vascular model, mustard-oil-stimulated ear vascular model, and carrageenan-induced paw edema model). Pretreatment of CE and VVE in a 1 : 3 combination dose dependently inhibited the production of nitric oxide (NO) and prostaglandin E2 (PGE2) and mRNA expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) through downregulation of the nuclear factor-κB (NF-κB) pathway in LPS-stimulated RAW264.7 macrophages. In vascular permeability-related mouse models, pretreatment with the CE-VVE 1 : 3 combination significantly reduced the permeability of peritoneal or ear veins caused by acetic acid and mustard oil, respectively. Furthermore, pretreatment of the CE-VVE 1 : 3 combination ameliorated inflammation and edema of the hind paw caused by carrageenan injection. Thus, the combination of CE and VVE showed significant anti-inflammatory qualities and anti-vascular leakage effects. These findings indicate that an optimal combination of CE and VVE may have a more synergistic effect than that of CE or VVE alone as a putative agent against vascular incompetence.

13.
Molecules ; 26(9)2021 04 30.
Article de Anglais | MEDLINE | ID: mdl-33946287

RÉSUMÉ

Skin moisturization is very crucial for maintaining the flexibility, viscoelasticity, and differentiation of the epidermis and its deprivation causes several diseases from dry skin to dermatitis. Aloe vera, a miracle plant having diverse medicinal properties including skin moisturization effects. This study investigated for the first time the molecular mechanism targeting skin moisturization effects of the Aloe vera flower and its major active constituent. By treating human epidermal keratinocytes (HaCaT cells) with Aloe vera flower water extract (AFWE), we found that AFWE upregulated epidermal involucrin by activating the expression of protein kinase C, p38, and ERK 1/2. Additionally, it modulated filaggrin, increased aquaporin expression, and hyaluronan synthesis via a balanced regulation of HAS1 and HYAL1 protein. Similarly, it was able to protect UVB-induced photodamage. Western blot analysis, ELISA, and qRT- PCR were performed to evaluate various epidermal differentiation markers and moisturization-related factors on human epidermal keratinocytes (HaCaT cells). TLC and HPLC were used to detect and analyze the chemical constituents. Among them, we found that an active component of Aloe vera flower, isoorientin (IO) has a high binding affinity to all of its targeted proteins such as involucrin, PKC, P38, etc. through molecular docking assay. This study indicated that the Aloe vera flower and its active constituent, IO can be used as a prominent ingredient to enhance skin barrier function and improve its related pathologies.


Sujet(s)
Aloe/composition chimique , Fleurs/composition chimique , Régulation de l'expression des gènes/effets des médicaments et des substances chimiques , Lutéoline/composition chimique , Lutéoline/pharmacologie , Extraits de plantes/composition chimique , Extraits de plantes/pharmacologie , Précurseurs de protéines/génétique , Marqueurs biologiques , Lignée cellulaire , Chromatographie en phase liquide à haute performance , Protéines filaggrine , Humains , Conformation moléculaire , Simulation de docking moléculaire , Simulation de dynamique moléculaire , Structure moléculaire , Agents protecteurs/composition chimique , Agents protecteurs/pharmacologie , Transduction du signal/effets des médicaments et des substances chimiques , Peau/effets des médicaments et des substances chimiques , Peau/métabolisme , Peau/effets des radiations , Relation structure-activité
14.
Brain Stimul ; 14(2): 217-225, 2021.
Article de Anglais | MEDLINE | ID: mdl-33444809

RÉSUMÉ

BACKGROUND: Transcranial ultrasound stimulation can acutely modulate brain activity, but the lasting effects on neurons are unknown. OBJECTIVE: To assess the excitability profile of neurons in the hours following transient ultrasound stimulation. METHODS: Primary rat cortical neurons were stimulated with a 40 s, 200 kHz pulsed ultrasound stimulation or sham-stimulation. Intrinsic firing properties were investigated through whole-cell patch-clamp recording by evoking action potentials in response to somatic current injection. Recordings were taken at set timepoints following ultrasound stimulation: 0-2 h, 6-8 h, 12-14 h and 24-26 h. Transmission electron microscopy was used to assess synaptic ultrastructure at the same timepoints. RESULTS: In the 0-2 h window, neurons stimulated with ultrasound displayed an increase in the mean frequency of evoked action potentials of 32% above control cell levels (p = 0.023). After 4-6 h this increase was measured as 44% (p = 0.0043). By 12-14 h this effect was eliminated and remained absent 24-26 h post-stimulation. These changes to action potential firing occurred in conjunction with statistically significant differences between control and ultrasound-stimulated neurons in action potential half-width, depolarisation rate, and repolarisation rate, that were similarly eliminated by 24 h following stimulation. These effects occurred in the absence of alterations to intrinsic membrane properties or synaptic ultrastructure. CONCLUSION: We report that stimulating neurons with 40 s of ultrasound enhances their excitability for up to 8 h in conjunction with modifications to action potential kinetics. This occurs in the absence of major ultrastructural change or modification of intrinsic membrane properties. These results can inform the application of transcranial ultrasound in experimental and therapeutic settings.


Sujet(s)
Axones , Neurones , Potentiels d'action , Animaux , Stimulation électrique , Mâle , Techniques de patch-clamp , Rats , Rat Wistar
15.
Immune Netw ; 20(4): e31, 2020 Aug.
Article de Anglais | MEDLINE | ID: mdl-32895618

RÉSUMÉ

The effectiveness of current influenza vaccines is considered suboptimal, and 1 way to improve the vaccines is using adjuvants. However, the current pool of adjuvants used in influenza vaccination is limited due to safety concerns. Aloe vera, or aloe, has been shown to have immunomodulatory functions and to be safe for oral intake. In this study, we explored the potential of orally administered processed Aloe vera gel (PAG) as an adjuvant for influenza vaccines in C57BL/6 mice. We first evaluated its adjuvanticity with a split-type pandemic H1N1 (pH1N1) Ag by subjecting the mice to lethal homologous influenza challenge. Oral PAG administration with the pH1N1 Ag increased survival rates in mice to levels similar to those of alum and MF59, which are currently used as adjuvants in influenza vaccine formulations. Similarly, oral PAG administration improved the survival of mice immunized with a commercial trivalent influenza vaccine against lethal homologous and heterologous virus challenge. PAG also increased hemagglutination inhibition and virus neutralization Ab titers against homologous and heterologous influenza strains following immunization with the split-type pH1N1 Ag or the commercial trivalent vaccine. Therefore, this study demonstrates that PAG may potentially be used as an adjuvant for influenza vaccines.

16.
Int J Mol Sci ; 21(15)2020 Jul 28.
Article de Anglais | MEDLINE | ID: mdl-32731326

RÉSUMÉ

Skin hyperpigmentation is generally characterized by increased synthesis and deposition of melanin in the skin. UP256, containing bakuchiol, is a well-known medication for acne vulgaris. Acne sometimes leaves dark spots on the skin, and we hypothesized that UP256 may be effective against hyperpigmentation-associated diseases. UP256 was treated for anti-melanogenesis and melanocyte dendrite formation in cultured normal human epidermal melanocytes as well as in the reconstituted skin and zebrafish models. Western blot analysis and glutathione S-transferase (GST)-pull down assays were used to evaluate the expression and interaction of enzymes related in melanin synthesis and transportation. The cellular tyrosinase activity and melanin content assay revealed that UP256 decreased melanin synthesis by regulating the expression of proteins related on melanogenesis including tyrosinase, TRP-1 and -2, and SOX9. UP256 also decreased dendrite formation in melanocytes via regulating the Rac/Cdc42/α-PAK signaling proteins, without cytotoxic effects. UP256 also inhibited ciliogenesis-dependent melanogenesis in normal human epidermal melanocytes. Furthermore, UP256 suppressed melanin contents in the zebrafish and the 3D human skin tissue model. All things taken together, UP256 inhibits melanin synthesis, dendrite formation, and primary cilium formation leading to the inhibition of melanogenesis.


Sujet(s)
Cils vibratiles/enzymologie , Régulation de l'expression des gènes codant pour des enzymes , Hyperpigmentation/enzymologie , Mélanocytes/enzymologie , Monophenol monooxygenase/biosynthèse , Transduction du signal , Régulation positive , Protéines de poisson-zèbre/biosynthèse , Danio zébré/métabolisme , Animaux , Lignée cellulaire , Cils vibratiles/anatomopathologie , Dendrites/enzymologie , Dendrites/anatomopathologie , Humains , Hyperpigmentation/traitement médicamenteux , Hyperpigmentation/anatomopathologie , Facteur de transcription SOX-9/métabolisme , Trypsine/métabolisme
17.
Prev Nutr Food Sci ; 25(2): 173-183, 2020 Jun 30.
Article de Anglais | MEDLINE | ID: mdl-32676469

RÉSUMÉ

Endothelial cell injury caused by oxidative stress is a critical factor in the initial stage of vascular diseases. Thus, identification of more effective antioxidants is a promising strategy to protect against endothelial cell injury. Recently, synergistic effects between phytochemicals have received renewed attention for their role in the treatment of various diseases. Vitis vinifera L. and Centella asiatica are well-known medicinal plants with various biological effects. However, the combination of the two has not previously been studied. Here, we investigated the effects of V. vinifera L. leaf and C. asiatica extract combination (VCEC), a standardized herbal blend comprising V. vinifera L. leaf extract (VE) and C. asiatica extract (CE), for its antioxidant activity and for the protection of endothelial cells against hydrogen peroxide (H2O2)-mediated oxidative damage in human umbilical vein endothelial cells (HUVECs). VCEC showed higher antioxidant activity than VE or CE in oxygen radical antioxidant capacity assays. In HUVECs, VCEC significantly suppressed increases in the production of intracellular reactive oxygen species, decreased levels of nitric oxide and vascular endothelial-cadherin, and increased endothelial hyperpermeability triggered by H2O2. Treatment with VE or CE alone ameliorated HUVEC injury in a pattern similar to VCEC, although their effects were significantly weaker than VCEC. Overall, VCEC exhibited a substantial synergistic effect on protecting endothelial cells against oxidative damage through its antioxidant activity. Therefore, VCEC could be developed as a potential agent for reducing the risk of vascular diseases related to oxidative stress.

18.
Biochem Biophys Res Commun ; 528(1): 46-53, 2020 07 12.
Article de Anglais | MEDLINE | ID: mdl-32456797

RÉSUMÉ

GATA1 is a master transcription factor of megakaryopoiesis and erythropoiesis, and loss-of-function mutation can induce accumulation of megakaryocyte-erythroid progenitors (MEPs) in mice and humans. Accordingly, the murine MEP cell line (termed G1ME2 cells) encoding doxycycline (dox)-inducible anti-Gata1 shRNA on Hprt locus has been developed. The cells were CD41+CD71+KIT+, expand under dox, stem cell factor, and thrombopoietin (TPO), and terminally differentiate into erythroid cells or megakaryocytes upon removal of dox. Surprisingly, in this study, these Gata1low murine MEPs displayed accelerated growth from around 90-100 days after cell culture, impeded megakaryocytic potential, and maintained erythropoiesis. We specified them as late G1ME2 cells and discovered that increased CD41-KIT+ population during long-term culture was the main reason for the delayed megakaryopoiesis. The CD41 expression level was partially de-repressed by PI3K/AKT inhibitors, suggesting that TPO-mediated cell survival signaling pathway might have impacted on CD41 in the late G1ME2 cells. Nevertheless, among the late cells, the CD41+KIT+ cells could still generate megakaryocytes on dox withdrawal. Taken together, G1ME2 cells could provide a good model to study molecular mechanism of hematopoiesis because of their ability to expand excessively without artificial immortalization.


Sujet(s)
Différenciation cellulaire , Facteur de transcription GATA-1/métabolisme , Progéniteurs érythroïdes et mégacaryocytaires/cytologie , Progéniteurs érythroïdes et mégacaryocytaires/métabolisme , Animaux , Cycle cellulaire , Prolifération cellulaire , Cellules cultivées , Souris , Glycoprotéine-IIb de membrane plaquettaire/métabolisme , Transduction du signal
19.
Scand J Immunol ; 91(3): e12856, 2020 Mar.
Article de Anglais | MEDLINE | ID: mdl-31794090

RÉSUMÉ

Atopic dermatitis (AD) is a chronic inflammatory skin disease. A hallmark of AD is dry itchy skin that results from defects in the epidermal barrier function. Aloe vera is used widely to promote general health and is administered topically to treat skin conditions such as eczema, burns and wounds. However, effects of A vera on AD were not fully elucidated. In this study, we investigated the oral administration of processed A vera gel (PAG) containing low molecular weight Aloe polysaccharides to treat ovalbumin (OVA)-induced AD in mice. Oral administration of PAG suppressed total and OVA-specific IgE production in sera and decreased the epidermal thickness of skin. Numbers of Ki-67-positive cells were reduced by PAG treatment. Expression levels of tight junction genes, including those that encode ZO-1, Claudin-1 and Claudin-8, were decreased in AD skin lesions, whereas oral administration of PAG partially restored the expression levels of tight junction genes. In addition, IL-4 and IL-17A mRNA transcript levels were reduced in skin lesions after PAG treatment. Taken together, our findings suggest that oral administration of PAG ameliorated AD, normalized tight junction gene expression and suppressed inflammatory cytokines in AD skin.


Sujet(s)
Aloe/composition chimique , Antiallergiques/pharmacologie , Eczéma atopique/étiologie , Exsudats végétaux/pharmacologie , Polyosides/pharmacologie , Jonctions serrées/effets des médicaments et des substances chimiques , Jonctions serrées/immunologie , Animaux , Antiallergiques/composition chimique , Marqueurs biologiques , Cytokines/métabolisme , Eczéma atopique/traitement médicamenteux , Eczéma atopique/anatomopathologie , Modèles animaux de maladie humaine , Évolution de la maladie , Femelle , Médiateurs de l'inflammation/métabolisme , Kératinocytes/effets des médicaments et des substances chimiques , Kératinocytes/immunologie , Kératinocytes/métabolisme , Souris , Ovalbumine/effets indésirables , Exsudats végétaux/composition chimique , Polyosides/composition chimique , Peau/effets des médicaments et des substances chimiques , Peau/immunologie , Peau/métabolisme , Peau/anatomopathologie
20.
Microb Drug Resist ; 26(3): 251-260, 2020 Mar.
Article de Anglais | MEDLINE | ID: mdl-31549905

RÉSUMÉ

This study compared changes in antimicrobial susceptibilities and molecular characteristics of coagulase-negative staphylococci (CNS) between the year 2000 and the year 2014-2015 to evaluate the policy of separating drug prescribing and dispensing in Korea. We obtained 68 CNS clinical isolates from two tertiary general hospitals before (the year 2000; n = 25) and after (the year 2014 - 2015; n = 43) implementation of the separation. Isolates were identified as Staphylococcus capitis, Staphylococcus epidermidis, Staphylococcus haemolyticus, Staphylococcus hominis, Staphylococcus saprophyticus, and Staphylococcus warneri. When minimal inhibitory concentrations of 14 antimicrobials were applied to isolates, resistance rates to gentamicin and oxacillin in 2000 were significantly higher than in 2014-2015 (p < 0.05). Fifty-seven isolates were methicillin-resistant CNS (MR-CNS), 42 of which were also multidrug resistant; overall, multidrug resistance decreased from 72% in the year 2000 to 55.8% in 2014-2015. Staphylococcal cassette chromosome mec (SCCmec) type III was the dominant type of MR-CNS in the year 2000, while SCCmec type IV was the dominant type in 2014-2015. Twenty-five sequence types (STs) were identified; ST2 appeared most frequently in both periods. After 15 years of implementation of this policy, multidrug resistance as well as methicillin and gentamicin resistance in CNS decreased, but not resistance to other antibiotics. Long-term surveillance at both genotypic and phenotypic levels of various species is necessary for further evaluation of this policy.


Sujet(s)
Antibactériens/pharmacologie , Ordonnances médicamenteuses/statistiques et données numériques , Multirésistance bactérienne aux médicaments/génétique , Infections à staphylocoques/épidémiologie , Staphylococcus epidermidis/génétique , Staphylococcus haemolyticus/génétique , Protéines bactériennes/génétique , Protéines bactériennes/métabolisme , Coagulase/déficit , Coagulase/génétique , Expression des gènes , Gentamicine/pharmacologie , Humains , Législation sur les produits chimiques ou pharmaceutiques , Tests de sensibilité microbienne , Oxacilline/pharmacologie , Phylogenèse , République de Corée/épidémiologie , Infections à staphylocoques/traitement médicamenteux , Infections à staphylocoques/microbiologie , Staphylococcus , Staphylococcus capitis/classification , Staphylococcus capitis/effets des médicaments et des substances chimiques , Staphylococcus capitis/génétique , Staphylococcus capitis/isolement et purification , Staphylococcus epidermidis/classification , Staphylococcus epidermidis/effets des médicaments et des substances chimiques , Staphylococcus epidermidis/isolement et purification , Staphylococcus haemolyticus/classification , Staphylococcus haemolyticus/effets des médicaments et des substances chimiques , Staphylococcus haemolyticus/isolement et purification , Staphylococcus hominis/classification , Staphylococcus hominis/effets des médicaments et des substances chimiques , Staphylococcus hominis/génétique , Staphylococcus hominis/isolement et purification , Staphylococcus saprophyticus , Centres de soins tertiaires
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