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1.
Sci Rep ; 14(1): 15260, 2024 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-38956136

RESUMO

KCNQ4 is a voltage-gated K+ channel was reported to distribute over the basolateral surface of type 1 vestibular hair cell and/or inner surface of calyx and heminode of the vestibular nerve connected to the type 1 vestibular hair cells of the inner ear. However, the precise localization of KCNQ4 is still controversial and little is known about the vestibular phenotypes caused by KCNQ4 dysfunction or the specific role of KCNQ4 in the vestibular organs. To investigate the role of KCNQ4 in the vestibular organ, 6-g hypergravity stimulation for 24 h, which represents excessive mechanical stimulation of the sensory epithelium, was applied to p.W277S Kcnq4 transgenic mice. KCNQ4 was detected on the inner surface of calyx of the vestibular afferent in transmission electron microscope images with immunogold labelling. Vestibular function decrease was more severe in the Kcnq4p.W277S/p.W277S mice than in the Kcnq4+/+ and Kcnq4+/p.W277S mice after the stimulation. The vestibular function loss was resulted from the loss of type 1 vestibular hair cells, which was possibly caused by increased depolarization duration. Retigabine, a KCNQ activator, prevented hypergravity-induced vestibular dysfunction and hair cell loss. Patients with KCNQ4 mutations also showed abnormal clinical vestibular function tests. These findings suggest that KCNQ4 plays an essential role in calyx and afferent of type 1 vestibular hair cell preserving vestibular function against excessive mechanical stimulation.


Assuntos
Células Ciliadas Vestibulares , Canais de Potássio KCNQ , Camundongos Transgênicos , Animais , Canais de Potássio KCNQ/metabolismo , Canais de Potássio KCNQ/genética , Células Ciliadas Vestibulares/metabolismo , Células Ciliadas Vestibulares/patologia , Camundongos , Fenilenodiaminas/farmacologia , Carbamatos/farmacologia , Vestíbulo do Labirinto/metabolismo , Vestíbulo do Labirinto/patologia , Vestíbulo do Labirinto/fisiopatologia
2.
Medicina (Kaunas) ; 60(1)2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38256384

RESUMO

Background and Objectives: The effects of midazolam, a benzodiazepine, on pain perception are complex on both spinal and supraspinal levels. It is not yet known whether remimazolam clinically attenuates or worsens pain. The present study investigated the effect of intraoperative remimazolam on opioid-induced hyperalgesia (OIH) in patients undergoing general anesthesia. Materials and Methods: The patients were randomized into three groups: group RHR (6 mg/kg/h initial dose followed by 1 mg/kg/h remimazolam and 0.3 µg /kg/min remifentanil), group DHR (desflurane and 0.3 µg /kg/min remifentanil) or group DLR (desflurane and 0.05 µg/kg /min remifentanil). The primary outcome was a mechanical hyperalgesia threshold, while secondary outcomes included an area of hyperalgesia and clinically relevant pain outcomes. Results: Group RHR had a higher mechanical hyperalgesia threshold, a smaller hyperalgesia postoperative area at 24 h, a longer time to first rescue analgesia (p = 0.04), lower cumulative PCA volume containing morphine postoperatively consumed for 24 h (p < 0.01), and lower pain intensity for 12 h than group DHR (p < 0.001). However, there was no significant difference in OIH between groups RHR and DLR. Conclusions: Group RHR, which received remimazolam, attenuated OIH, including mechanically evoked pain and some clinically relevant pain outcomes caused by a high dose of remifentanil. Further research is essential to determine how clinically meaningful and important the small differences observed between the two groups are.


Assuntos
Hiperalgesia , Laparoscopia , Humanos , Hiperalgesia/induzido quimicamente , Analgésicos Opioides/efeitos adversos , Remifentanil , Desflurano , Estudos Prospectivos , Benzodiazepinas , Percepção da Dor , Dor
3.
Clin Exp Emerg Med ; 11(1): 68-78, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37439139

RESUMO

OBJECTIVE: Agriculture is a hazardous industry. However, previous studies have focused on injuries to agricultural workers without comparison with injuries to nonagricultural workers. Therefore, we compared the clinical characteristics and outcomes of injuries reported at an emergency department (ED) between agricultural workers and nonagricultural workers. METHODS: We established a prospective ED-based agricultural injury surveillance system at a tertiary university hospital. Adult patients visiting the ED for an injury were divided into farmer and non-farmer groups depending on their engagement with agriculture. Using an adjusted multivariate analysis and propensity score matching (age, sex, inhabitant, and insurance type), we compared the clinical characteristics and outcomes of injuries between the farmer and non-farmer groups. RESULTS: In total, 38,556 injured adult patients (37,746 in the non-farmer group and 810 in the farmer group) were available for the unmatched sample analysis. The 1,620 matched subjects were equally classified after one-to-one nearest-neighbor propensity score matching. A multivariate logistic regression analysis of the unmatched sample revealed higher adjusted odds ratios (ORs) for intensive care unit admission (adjusted OR, 1.752; P=0.003) and overall surgery (adjusted OR, 1.870; P<0.001) in the farmer group. In contrast, univariate logistic regression analyses of the propensity score-matched sample found a higher OR in the farmer group only for overall surgery (OR, 1.786; P<0.001). CONCLUSION: Injuries of agricultural workers had higher odds only of requiring surgery; differences in injury-related mortality between groups were not statistically significant in either the matched or unmatched sample analyses.

4.
Clin Exp Emerg Med ; 10(2): 213-223, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36787902

RESUMO

OBJECTIVE: This study investigated the hospital diagnoses and characteristics of uncooperative prehospital patients suspected of acute stroke who could not undergo a prehospital stroke screening test (PHSST). METHODS: This retrospective observational study was conducted at a single academic hospital with a regional stroke center. We analyzed three scenario-based prehospital stroke screening performances using the final hospital diagnoses: (1) a conservative approach only in patients who underwent the PHSST, (2) a real-world approach that considered all uncooperative patients as screening positive, and (3) a contrapositive approach that all uncooperative patients were considered as negative. RESULTS: Of the 2,836 emergency medical services (EMS)-transported adult patients who met the prehospital criteria for suspicion of acute stroke, 486 (17.1%) were uncooperative, and 570 (20.1%) had a confirmed final diagnosis of acute stroke. The diagnosis in the uncooperative group did not differ from that in the cooperative group (22.0% vs. 19.7%, P=0.246). The diagnostic performances of the PHSST in the conservative approach were as follows: 79.5% sensitivity (95% confidence interval [CI], 75.5%-83.1%), 90.2% specificity (95% CI, 88.8%-91.6%), and 0.849 area under the receiver operating characteristic curve (AUC; 95% CI, 0.829-0.868). The sensitivity and specificity were 83.3% (95% CI, 80.0%-86.3%) and 75.2% (95% CI, 73.3%-76.9%), respectively, in the real-world approach and 64.6% (95% CI, 60.5%-68.5%) and 91.9% (95% CI, 90.7%-93.0%), respectively, in the contrapositive approach. No significant difference was evident in the AUC between the real-world approach and the contrapositive approach (0.792 [95% CI, 0.775-0.810] vs. 0.782 [95% CI, 0.762-0.803], P>0.05). CONCLUSION: We found overestimation (false positive) and underestimation (false negative) in the uncooperative group depending on the scenario-based EMS stroke screening policy for uncooperative prehospital patients suspected of acute stroke.

5.
Int J Mol Sci ; 23(8)2022 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-35457257

RESUMO

Matrix metalloproteinases (MMPs) are calcium-dependent zinc-containing endopeptidases involved in multiple cellular processes. Among the MMP isoforms, MMP-9 regulates cancer invasion, rheumatoid arthritis, and osteoarthritis by degrading extracellular matrix proteins present in the tumor microenvironment and cartilage and promoting angiogenesis. Here, we identified two potent natural product inhibitors of the non-catalytic hemopexin domain of MMP-9 using a novel quantum mechanical fragment molecular orbital (FMO)-based virtual screening workflow. The workflow integrates qualitative pharmacophore modeling, quantitative binding affinity prediction, and a raw material search of natural product inhibitors with the BMDMS-NP library. In binding affinity prediction, we made a scoring function with the FMO method and applied the function to two protein targets (acetylcholinesterase and fibroblast growth factor 1 receptor) from DUD-E benchmark sets. In the two targets, the FMO method outperformed the Glide docking score and MM/PBSA methods. By applying this workflow to MMP-9, we proposed two potent natural product inhibitors (laetanine 9 and genkwanin 10) that interact with hotspot residues of the hemopexin domain of MMP-9. Laetanine 9 and genkwanin 10 bind to MMP-9 with a dissociation constant (KD) of 21.6 and 0.614 µM, respectively. Overall, we present laetanine 9 and genkwanin 10 for MMP-9 and demonstrate that the novel FMO-based workflow with a quantum mechanical approach is promising to discover potent natural product inhibitors of MMP-9, satisfying the pharmacophore model and good binding affinity.


Assuntos
Produtos Biológicos , Metaloproteinase 9 da Matriz , Acetilcolinesterase , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Hemopexina , Ligantes , Metaloproteinase 13 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Inibidores de Metaloproteinases de Matriz/química , Metaloproteinases da Matriz , Simulação de Acoplamento Molecular
6.
Clin Exp Otorhinolaryngol ; 14(4): 367-373, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33092316

RESUMO

OBJECTIVES: The aims of this study were to investigate the effects of intratympanic injections of isosorbide on vestibular function in animal models of endolymphatic hydrops and to find a new treatment option for the acute onset of vertigo in Ménière disease (MD). METHODS: Seventy male guinea pigs received intratympanic injection of isosorbide (IT-ISB). The animals were divided into three study groups: control, a chronic hydrops model, and an acute hydrops model. Intracochlear drug concentrations were measured using high-performance liquid chromatography. Vestibular function was analyzed using an animal rotator test with bidirectional sinusoidal harmonic acceleration before and after IT-ISB administration. Histological changes were also investigated. RESULTS: ISB successfully permeated the perilymph through the round window membrane (RWM) at all three concentrations (25%, 50%, and 100%). In the chronic hydrops model, while IT-ISB histologically induced a reduction of endolymphatic hydrops, vestibular function was unchanged. In the acute hydrops model, no endolymphatic hydrops was histologically observed, and vestibular symmetry was also preserved after IT-ISB. CONCLUSION: ISB passed through the RWM into the perilymphatic space even at lower concentrations. IT-ISB histologically reduced hydrops in the chronic model and preserved symmetrical vestibular function in the acute model. IT-ISB could be a treatment candidate for acute attacks of vertigo in MD.

7.
Bioorg Chem ; 100: 103906, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32422387

RESUMO

A new series of 4H-chromene-3-carboxylate derivatives were synthesized using multicomponent reaction of salicylaldehyde, ethyl acetoacetate and dimedone in ethanol with K3PO4 as a catalyst at 80 °C. The structures of all newly synthesized compounds were confirmed by spectral techniques viz. IR, 1H NMR, 13C NMR, and LCMS analysis. The newly synthesized compounds 4a to 4j were screened against elastase enzyme. Interestingly, all these compounds found to be potent elastase inhibitors with much lower IC50 value. The compound 4b was found to be most potent elastase inhibitor (IC50 = 0.41 ± 0.01 µM) amongst the synthesized series against standard Oleanolic Acid (IC50 value = 13.45 ± 0.0 µM). The Kinetics mechanism for compound 4b was analyzed by Lineweaver-Burk plots which revealed that compound inhibited elastase competitively by forming an enzyme-inhibitor complex. Along with this, all the synthesized compounds (4a - 4j) exhibits excellent DPPH free radical scavenging ability. The inhibition constant Ki for compound 4b was found to be 0.6 µM. The computational study was comprehensible with the experimental results with good docking energy values (Kcal/mol). Therefore, these molecules can be considered as promising medicinal scaffolds for the treatment of skin-related maladies.


Assuntos
Benzopiranos/química , Benzopiranos/farmacologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Elastase Pancreática/antagonistas & inibidores , Animais , Benzopiranos/síntese química , Ácidos Carboxílicos/síntese química , Ácidos Carboxílicos/química , Ácidos Carboxílicos/farmacologia , Quimioinformática , Inibidores Enzimáticos/síntese química , Simulação de Acoplamento Molecular , Pâncreas/enzimologia , Elastase Pancreática/química , Elastase Pancreática/metabolismo , Suínos
8.
Bioorg Chem ; 94: 103445, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31826809

RESUMO

In the current research work, different N-(substituted-phenyl)-4-{(4-[(E)-3-phenyl-2-propenyl]-1-piperazinyl}butanamides have been synthesized according to the protocol described in scheme 1. The synthesis was initiated by reacting various substituted anilines (1a-e) with 4-chlorobutanoyl chloride (2) in aqueous basic medium to give various electrophiles, 4-chloro-N-(substituted-phenyl)butanamides (3a-e). These electrophiles were then coupled with 1-[(E)-3-phenyl-2-propenyl]piperazine (4) in polar aprotic medium to attain the targeted N-(substituted-phenyl)-4-{(4-[(E)-3-phenyl-2-propenyl]-1-piperazinyl}butanamides (5a-e). The structures of all derivatives were identified and characterized by proton-nuclear magnetic resonance (1H NMR), carbon-nuclear magnetic resonance (13C NMR) and Infra-Red (IR) spectral data along with CHN analysis. The in vitro inhibitory potential of these butanamides was evaluated against Mushroom tyrosinase, whereby all compounds were found to be biologically active. Among them, 5b exhibited highest inhibitory potential with IC50 value of 0.013 ± 0.001 µM. The same compound 5b was also assayed through in vivo approach, and it was explored that it significantly reduced the pigments in zebrafish. The in silico studies were also in agreement with aforesaid results. Moreover, these molecules were profiled for their cytotoxicity through hemolytic activity, and it was found that except 5e, all other compounds showed minimal toxicity. The compound 5a also exhibited comparable results. Hence, some of these compounds might be worthy candidates for the formulation and development of depigmentation drugs with minimum side effects.


Assuntos
Amidas/farmacologia , Inibidores Enzimáticos/farmacologia , Melaninas/antagonistas & inibidores , Monofenol Mono-Oxigenase/antagonistas & inibidores , Piperazina/farmacologia , Amidas/síntese química , Amidas/química , Animais , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Melaninas/metabolismo , Modelos Moleculares , Estrutura Molecular , Monofenol Mono-Oxigenase/metabolismo , Piperazina/síntese química , Piperazina/química , Relação Estrutura-Atividade , Peixe-Zebra
9.
Hear Res ; 386: 107860, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31869657

RESUMO

Purinergic receptors protect the cochlea during high-intensity stimulation by providing a parallel shunt pathway through non-sensory neighboring epithelial cells for cation absorption. So far, there is no direct functional evidence for the presence and type/subunit of purinergic receptors in the utricle of the vestibular labyrinth. The goal of the present study was to investigate which purinergic receptors are expressed and carry cation-absorption currents in the utricular transitional cells and macula. Purinergic agonists induced cation-absorption currents with a potency order of ATP > bzATP = αßmeATP â‰« ADP = UTP = UDP. ATP and bzATP are full agonists, whereas αßmeATP is a partial agonist. ATP-induced currents were partially inhibited by 100 µM suramin, 10 µM pyridoxal-phosphate-6-azo-(benzene-2,4-disulfonic acid (PPADS), or 5 µM 5-(3-bromophenyl)-1,3-dihydro-2H-benzofuro[3,2-e]-1, 4-diazepin-2-one (5-BDBD), and almost completely blocked by 100 µM Gd3+ or by a combination of 10 µM PPADS and 5 µM 5-BDBD. Expression of the P2RX2 and P2RX4 receptor was detected by immunocytochemistry in transitional cells and macular supporting cells. This is the first study to demonstrate that ATP induces cation currents carried by a combination of P2RX2 and P2RX4 in utricular transitional and macular epithelial cells, and supporting the hypothesis that purinergic receptors protect utricular hair cells during elevated stimulus intensity levels.


Assuntos
Trifosfato de Adenosina/metabolismo , Células Labirínticas de Suporte/metabolismo , Receptores Purinérgicos P2X2/metabolismo , Receptores Purinérgicos P2X4/metabolismo , Sáculo e Utrículo/metabolismo , Animais , Agonismo Parcial de Drogas , Células Labirínticas de Suporte/efeitos dos fármacos , Potenciais da Membrana , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Agonistas do Receptor Purinérgico P2X/farmacologia , Antagonistas do Receptor Purinérgico P2X/farmacologia , Receptores Purinérgicos P2X2/efeitos dos fármacos , Receptores Purinérgicos P2X4/efeitos dos fármacos , Sáculo e Utrículo/citologia , Sáculo e Utrículo/efeitos dos fármacos , Transdução de Sinais , Transportadores de Sulfato/genética , Transportadores de Sulfato/metabolismo
10.
Bioorg Chem ; 92: 103201, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31445195

RESUMO

We have carried out the synthesis of new 4-oxoquinazolin-3(4H)-yl)furan-2-carboxamide derivatives by the reaction between isatoic anhydride, 2-furoic hydrazide and substituted salicylaldehydes in ethanol: water (5:5 v/v) solvent system using p-TSA as a catalyst under ultrasound irradiation at room temperature. The structures of newly synthesized compounds were confirmed through spectral techniques such as IR, 1H NMR, 13C NMR, and LCMS. The important features of this protocol include simple and easy workup procedure, reaction carried out at ambient temperature, use of ultrasound and high yield of oxoquinazolin-3(4H)-yl)furan-2-carboxamides in short reaction time. The synthesized compounds 4a-4j were screened against tyrosinase enzyme and all these compounds found to be potent inhibitors with much lower IC50 value of 0.028 ±â€¯0.016 to 1.775 ±â€¯0.947 µM than the standard kojic acid (16.832 ±â€¯1.162 µM). The kinetics mechanism for compound 4e was analyzed by Lineweaver-Burk plots which revealed that compound inhibited tyrosinase non-competitively by forming an enzyme-inhibitor complex. Along with this all the synthesized compounds (4a-4j) were scanned for their DPPH free radical scavenging ability. The outputs received through in vitro and in silico analysis are coherent to the each other with good binding energy values (kcal/mol) posed by synthesized ligands.


Assuntos
Inibidores Enzimáticos/síntese química , Monofenol Mono-Oxigenase/antagonistas & inibidores , Quinolonas/síntese química , Sequência de Aminoácidos , Sítios de Ligação , Quimioinformática , Simulação por Computador , Desenho de Fármacos , Inibidores Enzimáticos/metabolismo , Furanos/química , Cinética , Simulação de Acoplamento Molecular , Estrutura Molecular , Ligação Proteica , Pironas/metabolismo , Relação Estrutura-Atividade , Ondas Ultrassônicas
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