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1.
JCI Insight ; 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38771644

RESUMO

Hypotrichosis is a genetic disorder which characterized by a diffuse and progressive loss of scalp and/or body hair. Nonetheless, the causative genes for several affected individuals remain elusive, and the underlying mechanisms have yet to be fully elucidated. Here, we discovered a dominant variant in ADAM17 gene caused hypotrichosis with woolly hair. Adam17 (p.D647N) knock-in mice model mimicked the hair abnormality in patients. ADAM17 (p.D647N) mutation led to hair follicle stem cells (HFSCs) exhaustion and caused abnormal hair follicles, ultimately resulting in alopecia. Mechanistic studies revealed that ADAM17 binds directly to E3 ubiquitin ligase TRIM47. ADAM17 (p.D647N) variant enhanced the association between ADAM17 and TRIM47, leading to an increase in ubiquitination and subsequent degradation of ADAM17 protein. Furthermore, reduced ADAM17 protein expression affected Notch signaling pathway, impairing the activation, proliferation, and differentiation of HFSCs during hair follicle regeneration. Overexpression of NICD rescued the reduced proliferation ability caused by Adam17 variant in primary fibroblast cells.

2.
Br J Pharmacol ; 180(10): 1339-1361, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36521846

RESUMO

BACKGROUND AND PURPOSE: Atopic dermatitis is a common chronic pruritic inflammatory disease of the skin involving neuro-immune communication. Neuronal mechanism-based therapeutic treatments remain lacking. We investigated the efficacy of intravenous lidocaine therapy on atopic dermatitis and the underlying neuro-immune mechanism. EXPERIMENTAL APPROACH: Pharmacological intervention, immunofluorescence, RNA-sequencing, genetic modification and immunoassay were performed to dissect the neuro-immune basis of itch and inflammation in atopic dermatitis-like mouse model and in patients. KEY RESULTS: Lidocaine alleviated skin lesions and itch in both atopic dermatitis patients and calcipotriol (MC903)-induced atopic dermatitis model by blocking subpopulation of sensory neurons. QX-314, a charged NaV blocker that enters through pathologically activated large-pore ion channels and selectivity inhibits a subpopulation of sensory neurons, has the same effects as lidocaine in atopic dermatitis model. Genetic silencing NaV 1.8-expressing sensory neurons was sufficient to restrict cutaneous inflammation and itch in the atopic dermatitis model. However, pharmacological blockade of TRPV1-positive nociceptors only abolished persistent itch but did not affect skin inflammation in the atopic dermatitis model, indicating a difference between sensory neuronal modulation of skin inflammation and itch. Inhibition of activity-dependent release of calcitonin gene-related peptide (CGRP) from sensory neurons by lidocaine largely accounts for the therapeutic effect of lidocaine in the atopic dermatitis model. CONCLUSION AND IMPLICATIONS: NaV 1.8+ sensory neurons play a critical role in pathogenesis of atopic dermatitis and lidocaine is a potential anti-inflammatory and anti-pruritic agent for atopic dermatitis. A dissociable difference for sensory neuronal modulation of skin inflammation and itch contributes to further understanding of pathogenesis in atopic dermatitis.


Assuntos
Dermatite Atópica , Camundongos , Animais , Dermatite Atópica/tratamento farmacológico , Dermatite Atópica/patologia , Prurido/tratamento farmacológico , Pele/patologia , Inflamação/patologia , Células Receptoras Sensoriais
3.
Molecules ; 27(23)2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36500701

RESUMO

As a major public health problem, the prevalence of Acinetobacter baumannii (A. baumannii) infections in hospitals due to the pathogen's multiple-antibiotic resistance has attracted extensive attention. We previously reported a series of 1,3-diamino-7H-pyrrolo[3,2-f]quinazoline (PQZ) compounds, which were designed by targeting Escherichia coli dihydrofolate reductase (ecDHFR), and exhibited potent antibacterial activities. In the current study, based on our molecular-modeling study, it was proposed that PQZ compounds may function as potent A. baumannii DHFR (abDHFR)-inhibitors as well, which inspired us to consider their anti-A. baumannii abilities. We further found that three PQZ compounds, OYYF-171, -172, and -175, showed significant antibacterial activities against A. baumannii, including multidrug-resistant (MDR) strains, which are significantly stronger than the typical DHFR-inhibitor, trimethoprim (TMP), and superior to, or comparable to, the other tested antibacterial agents belonging to ß-lactam, aminoglycoside, and quinolone. The significant synergistic effect between the representative compound OYYF-171 and the dihydropteroate synthase (DHPS)-inhibitor sulfamethoxazole (SMZ) was observed in both the microdilution-checkerboard assay and time-killing assay, which indicated that using SMZ in combination with PQZ compounds could help to reduce the required dosage and forestall resistance. Our study shows that PQZ is a promising scaffold for the further development of folate-metabolism inhibitors against MDR A. baumannii.


Assuntos
Infecções por Acinetobacter , Acinetobacter baumannii , Antagonistas do Ácido Fólico , Humanos , Quinazolinas/farmacologia , Testes de Sensibilidade Microbiana , Infecções por Acinetobacter/tratamento farmacológico , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Antagonistas do Ácido Fólico/farmacologia , Tetra-Hidrofolato Desidrogenase , Farmacorresistência Bacteriana Múltipla
4.
Dermatol Ther ; 35(12): e15947, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36259491

RESUMO

Children with severe atopic dermatitis (AD) can benefit from intravenous immunoglobulin (IVIG) therapy. This study aimed to identify the efficacy and safety of IVIG therapy in children with severe AD. Twenty pediatric AD patients were enrolled in this study. Patients with an Investigator's Global Assessment score of 0 or 1 or a reduction of 2 points after treatment were defined as high-responders (HRs), otherwise, they were defined as low-responders (LRs). Twelve patients (60%) achieved an excellent treatment response after 2 months, while eight (40%) had a low response. The Scoring Atopic Dermatitis index had improved significantly at 2 months post-treatment compared with baseline (p < 0.001). Baseline total serum IgE levels and eosinophil counts were elevated in all subjects and decreased significantly at 2 months post-treatment (p = 0.004 and 0.021, respectively). Baseline IgE levels were significantly higher in the HR group compared with the LR group (p = 0.020). The treatment was well tolerated. Fever was the most common adverse event and occurred in five patients (25%). In conclusion, IVIG could be a safe and effective therapy for children with severe AD and may be more effective in patients with higher IgE levels. Further studies are needed to investigate the different therapeutic responses in patients with different AD phenotypes.


Assuntos
Dermatite Atópica , Humanos , Dermatite Atópica/diagnóstico , Dermatite Atópica/tratamento farmacológico , Imunoglobulinas Intravenosas/efeitos adversos , Índice de Gravidade de Doença , Contagem de Leucócitos , Imunoglobulina E , Resultado do Tratamento
5.
Sci Rep ; 12(1): 13600, 2022 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-35948595

RESUMO

The brachistochrone (shortest-time) curve is the path connecting two points that enables the shortest travel time. This work explores the "brachistochrone path" of fire spread connecting two points at the same altitude and with a fixed path length. The starting and ending points are connected by both thermally thin fuels (thin wires) and thermally thick fuels (PMMA bars). Flame-spread paths of triangular, rectangular, and circular shapes with different heights and inclinations are explored. Results show that having a local maximum flame-spread rate does not result in the shortest overall travel time. For thin-wire paths, the fastest overall-path fire spread occurs, when the upward spread path is vertical, and the path height reaches a maximum, as demonstrated by the theoretical analysis. Differently, for thick PMMA-bar paths, the brachistochrone condition occurs when the path length of the vertical upward spread reaches the maximum, because the upward spread is about ten times faster than the downward spread. This study extends the conventional problem of the fastest fire spread to the shortest-time problem of the whole fire path, and it may help optimize the fuel distribution inside the built environment and estimate available safe egress time in building and wildland fires.


Assuntos
Incêndios , Polimetil Metacrilato , Viagem
6.
Eur J Radiol ; 154: 110426, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35797790

RESUMO

PURPOSE: We sought to evaluate the performance of a new "one-stop-shop" scan protocol combining brain computed tomography perfusion (CTP) and head-and-neck CT angiography (CTA) imaging for acute stroke patients using a 256-detector CT scanner. METHOD: From March to August 2020, 60 patients (30 men and 30 women) aged 22-88 years with suspected acute stroke were enrolled and randomly divided into 2 groups to undergo brain CTP and head-and-neck CTA with a 256-detector CT system. Group A used traditional scan protocol with a separate brain CTP and head-and-neck CT examination that included non-contrast-enhanced and contrast-enhanced acquisitions; group B used the new "one-stop-shop" scan protocol with head-and-neck CTA data inserted into brain CTP scans at the peak time (PT) of the arterial phase. The insertion point of the head-and-neck CTA data was determined by a test bolus. The examination time, contrast dose, radiation dose, and image quality were compared between the groups. RESULTS: The total contrast dose was reduced by 40% in group B compared to group A (60 mL vs. 100 mL). The imaging time was 52.5 ± 2.6 s in group B and 74.9 ± 3.3 s in group A, showing a reduction of approximately 43% in group B. There was no significant difference in image quality both quantitatively and qualitatively between the groups (all P > 0.05). Group B had a slight reduction in dose length product (1139.0 ± 45.3 vs. 1211.6 ± 31.9 mGy·cm, P < 0.001). CONCLUSIONS: The proposed "one-stop-shop" scan protocol combining brain CTP and head-and-neck CTA on a 256-detector CT system can reduce imaging time and contrast dose, without affecting image quality or perfusion results, compared to the traditional protocol of separating the examinations.


Assuntos
Angiografia por Tomografia Computadorizada , Acidente Vascular Cerebral , Feminino , Humanos , Masculino , Encéfalo/diagnóstico por imagem , Angiografia por Tomografia Computadorizada/métodos , Perfusão , Acidente Vascular Cerebral/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos
7.
Front Pharmacol ; 13: 849498, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35401212

RESUMO

Acidosis is a hallmark of ischemic stroke and a promising neuroprotective target for preventing neuronal injury. Previously, genetic manipulations showed that blockade of acid-sensing ion channel 1a (ASIC1a)-mediated acidotoxicity could dramatically alleviate the volume of brain infarct and restore neurological function after cerebral ischemia. However, few pharmacological candidates have been identified to exhibit efficacy on ischemic stroke through inhibition of ASIC1a. In this work, we examined the ability of a toxin-inspired compound 5b (C5b), previously found to effectively inhibit ASIC1a in vitro, to exert protective effects in animal models of ischemic stroke in vivo. We found that C5b exerts significant neuroprotective effects not only in acid-induced neuronal death in vitro but also ischemic brain injury in vivo, suggesting that ASIC1a is a druggable target for therapeutic development. More importantly, C5b is able to cross the blood brain barrier and significantly reduce brain infarct volume when administered intravenously in the ischemic animal model, highlighting its systemic availability for therapies against neurodegeneration due to acidotoxicity. Together, our data demonstrate that C5b is a promising lead compound for neuroprotection through inhibiting ASIC1a, which warrants further translational studies.

8.
Brain Imaging Behav ; 14(6): 2269-2280, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31432318

RESUMO

Amygdala is an important locus of dysfunction implicated in major depressive disorder(MDD). Aberrant amygdala networks(AN) had been reported in resting-state functional magnetic resonance imaging (rs-fMRI) study. The safety and efficacy of acupuncture treatment for MDD have been verified in previous clinical studies. This study is aimed to investigate whether acupuncture at GV20 could modulate the abnormal AN of patients with the first-episode, drug-naïve MDD by using rs-fMRI combined with functional connectivity (FC) method. Thirty MDD patient underwent 6-min rs-fMRI scans respectively before and after 20-min electro-acupuncture stimulate(EAS) at GV20. Twenty-nine healthy subjects underwent only a 6-min rs-fMRI scan. Based on the amygdala as the seed region, FC method was adopted to examine abnormal AN in patients by comparing with healthy subjects and to evaluate the influence of EAS on intrinsic connectivity within the AN in patients with MDD. Compared to healthy subjects, MDD patients had aberrant intrinsic AN which mainly showed increased FC between amygdala and hippocampus, precuneus, precentral gyrus and angular gyrus, as well as decreased FC between amygdala and orbital frontal cortex(OFC). Moreover, our results indicated that EAS at GV20 induced increased/decreased FC between amygdala and certain regions in MDD patients. In addition, the intrinsic amygdala FC within other certain brain regions in MDD patients were regulated by EAS at GV20. The abnormal AN of MDD patients could be modulated by EAS at GV20. Our findings may further provide the potential imaging evidence to support the modulatory mechanisms of acupuncture on MDD.


Assuntos
Terapia por Acupuntura , Tonsila do Cerebelo , Transtorno Depressivo Maior , Tonsila do Cerebelo/diagnóstico por imagem , Tonsila do Cerebelo/fisiopatologia , Transtorno Depressivo Maior/diagnóstico por imagem , Transtorno Depressivo Maior/fisiopatologia , Transtorno Depressivo Maior/terapia , Humanos , Imageamento por Ressonância Magnética
9.
Food Chem Toxicol ; 49(8): 1711-7, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21549173

RESUMO

Long chain polyunsaturated fatty acids (LC-PUFA), ARA (arachidonic acid, 20:4n-6) and DHA (docosahexaenoic acid, 22:6n-3) have positive effects and environment pollutants, polychlorinated dibenzo-p-dioxins/dibenzofurans(PCDD/F) and polychlorinated biphenyls (PCB) have negative effects on neural development during early life. Placental dioxin/PCB serves as markers for cumulative exposure to fetus. Fatty acid composition of placenta depends on nutrient supply during pregnancy, serving as indicators for fetal ARA and DHA accretion. This study investigated correlation between placental PCDD/F and PCB toxic equivalent (TEQ) and LC-PUFA in 34 pregnant women from Taiwan. Placental PCDF TEQ were inversely correlated with placental ARA (p=0.020), C20:3n-6 (p=0.01), C22:4n-6 (p=0.04), C22:5n-6 (p<0.01) and with DHA (p=0.03), but ARA and DHA did not vary with PCDD, dioxin-like and indicator PCB. After adjustment for age and body mass index, a one-unit PCDF TEQ increase was associated with 1.021%w/w and 0.312%w/w decreases in ARA (ß=-1.021, p=0.03) and DHA (ß=-0.312, p=0.03). Since ARA and DHA were unrelated to three classes of toxins, and a weak negative association was found with PCDF, these data provide no basis for discouraging marine fish consumption during pregnancy for Taiwan women on the basis of these organics. Pregnant women should consume fish for its unique package of nutrients while avoiding few species with high organic pollutant or mercury contamination.


Assuntos
Ácidos Araquidônicos/farmacologia , Benzofuranos/análise , Ácidos Docosa-Hexaenoicos/farmacologia , Placenta/química , Bifenilos Policlorados/análise , Dibenzodioxinas Policloradas/análogos & derivados , Adulto , Ácidos Araquidônicos/análise , Cromatografia Gasosa , Dibenzofuranos Policlorados , Ácidos Docosa-Hexaenoicos/análise , Poluentes Ambientais/análise , Feminino , Ionização de Chama , Contaminação de Alimentos , Humanos , Modelos Lineares , Espectrometria de Massas , Defeitos do Tubo Neural/embriologia , Projetos Piloto , Dibenzodioxinas Policloradas/análise , Gravidez , Fenômenos Fisiológicos da Nutrição Pré-Natal , Taiwan
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