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2.
Plants (Basel) ; 13(5)2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38475547

RESUMO

Salix chaenomeloides Kimura, commonly known as pussy willow, is a deciduous shrub and tree belonging to the Salicaceae family. The genus Salix spp. has been known as a healing herb for the treatment of fever, inflammation, and pain relief. The current study aimed to investigate the potential bioactive natural products from S. chaenomeloides leaves and evaluate their antibacterial activity against Helicobacter pylori. A phytochemical investigation of the ethanol (EtOH) extract of S. chaenomeloides leaves led to the isolation of 13 phenolic compounds (1-13) from the ethyl acetate (EtOAc) fraction, which showed antibacterial activity against H. pylori strain 51. The chemical structure of a new phenolic glycoside, chaenomelin (1), was established by a detailed analysis of 1D and 2D (1H-1H correlation spectroscopy (COSY), heteronuclear single-quantum coherence (HSQC), and heteronuclear multiple-bond correlation (HMBC)) nuclear magnetic resonance (NMR), high-resolution electrospray ionization mass spectroscopy (HR-ESIMS), and chemical reactions. The other known compounds were identified as 5-O-trans-p-coumaroyl quinic acid methyl ester (2), tremulacin (3), citrusin C (4), benzyl 3-O-ß-d-glucopyranosyl-7-hydroxybenzoate (5), tremuloidin (6), 1-[O-ß-d-glucopyranosyl(1→2)-ß-d-glucopyranosyl]oxy-2-phenol (7), arbutin cinnamate (8), tremulacinol (9), catechol (10), 4-hydroxybenzaldehyde (11), kaempferol 3-rutinoside (12), and narcissin (13), based on the comparison of their NMR spectra with the reported data and liquid chromatography/mass spectrometry (LC/MS) analysis. The isolated compounds were evaluated for antibacterial activity against H. pylori strain 51. Among the isolates, 1-[O-ß-d-glucopyranosyl(1→2)-ß-d-glucopyranosyl]oxy-2-phenol (7) and arbutin cinnamate (8) exhibited antibacterial activity against H. pylori strain 51, with inhibitions of 31.4% and 33.9%, respectively, at a final concentration of 100 µM. These results were comparable to that of quercetin (38.4% inhibition), which served as a positive control. Generally, these findings highlight the potential of the active compounds 7 and 8 as antibacterial agents against H. pylori.

3.
Angew Chem Int Ed Engl ; 63(3): e202312942, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38062619

RESUMO

The development of a small-molecule probe designed to selectively target neurons would enhance the exploration of intricate neuronal structures and functions. Among such probes, NeuO stands out as the pioneer and has gained significant traction in the field of research. Nevertheless, neither the mechanism behind neuron-selectivity nor the cellular localization has been determined. Here, we introduce NeuM, a derivative of NeuO, designed to target neuronal cell membranes. Furthermore, we elucidate the mechanism behind the selective neuronal membrane trafficking that distinguishes neurons. In an aqueous buffer, NeuM autonomously assembles into micellar structures, leading to the quenching of its fluorescence (Φ=0.001). Upon exposure to neurons, NeuM micelles were selectively internalized into neuronal endosomes via clathrin-mediated endocytosis. Through the endocytic recycling pathway, NeuM micelles integrate into neuronal membrane, dispersing fluorescent NeuM molecules in the membrane (Φ=0.61). Molecular dynamics simulations demonstrated that NeuM, in comparison to NeuO, possesses optimal lipophilicity and molecular length, facilitating its stable incorporation into phospholipid layers. The stable integration of NeuM within neuronal membrane allows the prolonged monitoring of neurons, as well as the visualization of intricate neuronal structures.


Assuntos
Clatrina , Micelas , Clatrina/metabolismo , Endocitose/fisiologia , Endossomos/metabolismo , Neurônios/metabolismo
4.
Bioorg Med Chem ; 95: 117513, 2023 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-37931520

RESUMO

In this article, the development of fluorescent imaging probes for the detection of Alzheimer's disease (AD)-associated protein aggregates is described. Indane derivatives with a donor-π-acceptor (D-π-A) structure were designed and synthesized. The probes were evaluated for their ability to bind to ß-amyloid (Aß) protein aggregates, which are a key pathological hallmark of AD. The results showed that several probes exhibited significant changes in fluorescence intensity at wavelengths greater than 600 nm when they were bound to Aß aggregates compared to the Aß monomeric form. Among the tested probes, four D-π-A type indane derivatives showed promising binding selectivity to Aß aggregates over non-specific proteins such as bovine serum albumin (BSA). The molecular docking study showed that our compounds were appropriately located along the Aß fibril axis through the hydrophobic tunnel structure. Further analysis revealed that the most active compound having dimethylaminopyridyl group as an election donor and dicyano group as an electron acceptor could effectively stain Aß plaques in brain tissue samples from AD transgenic mice. These findings suggest that our indane-based compounds have the potential to serve as fluorescent probes for the detection and monitoring of Aß aggregation in AD.


Assuntos
Doença de Alzheimer , Camundongos , Animais , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/metabolismo , Corantes Fluorescentes/química , Agregados Proteicos , Simulação de Acoplamento Molecular , Peptídeos beta-Amiloides/metabolismo , Camundongos Transgênicos , Encéfalo/metabolismo , Placa Amiloide/química , Placa Amiloide/diagnóstico , Placa Amiloide/patologia
5.
ACS Omega ; 8(45): 42548-42554, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-38024697

RESUMO

Gastric problems are often caused by the well-known Helicobacter pylori (H. pylori) bacterium. One of the biggest obstacles to the treatment of H. pylori infections is increasing the antibiotic resistance. During our search for naturally derived anti-H. pylori compounds, six major compounds were isolated from the methylene chloride (CH2Cl2) and ethyl acetate (EtOAc) fractions of Rumex acetosa that showed anti-H. pylori activity. Three anthraquinones and three anthraquinone glucosides were identified as the major chemical constituents of the CH2Cl2 and EtOAc fractions, respectively. The chemical structures were identified to be emodin (1), chrysophanol (2), physcion (3), emodin-8-O-ß-d-glucoside (4), chrysophanol-8-O-ß-d-glucoside (5), and physcion-8-O-ß-d-glucoside (6) by UV, 1H NMR, 13C NMR, and mass spectrometry. Anti-H. pylori activity, including the minimum inhibitory concentration (MIC) value of each compound, was evaluated against two H. pylori strains. All isolates exhibited anti-H. pylori activity with different potencies, with an MIC value ranging between 3.13 and 25 µM. However, some variations were found between the two strains. While compound 5 displayed the most potent antibacterial activity with an MIC50 value of 8.60 µM and an MIC90 value of 15.7 µM against H. pylori strain 51, compound 1 exhibited the most potent inhibitory activity against H. pylori strain 43504. The two compounds also showed moderate urease inhibitory activity, with compound 1 demonstrating activity higher than that of compound 5. Furthermore, a molecular docking study revealed the high binding ability of compounds 1 and 5 to the active site of H. pylori urease. The present study suggests that the six anthraquinones isolated from R. acetosa with the whole parts of this plant may be natural candidates for the treatment of H. pylori infection. Further studies are required to determine the exact mechanism of action and to evaluate safety issues in the human body.

6.
Micromachines (Basel) ; 14(6)2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37374686

RESUMO

This study investigates the operating characteristics of AlGaN/GaN high-electron-mobility transistors (HEMTs) by applying HfO2 as the passivation layer. Before analyzing HEMTs with various passivation structures, modeling parameters were derived from the measured data of fabricated HEMT with Si3N4 passivation to ensure the reliability of the simulation. Subsequently, we proposed new structures by dividing the single Si3N4 passivation into a bilayer (first and second) and applying HfO2 to the bilayer and first passivation layer only. Ultimately, we analyzed and compared the operational characteristics of the HEMTs considering the basic Si3N4, only HfO2, and HfO2/Si3N4 (hybrid) as passivation layers. The breakdown voltage of the AlGaN/GaN HEMT having only HfO2 passivation was improved by up to 19%, compared to the basic Si3N4 passivation structure, but the frequency characteristics deteriorated. In order to compensate for the degraded RF characteristics, we modified the second Si3N4 passivation thickness of the hybrid passivation structure from 150 nm to 450 nm. We confirmed that the hybrid passivation structure with 350-nm-thick second Si3N4 passivation not only improves the breakdown voltage by 15% but also secures RF performance. Consequently, Johnson's figure-of-merit, which is commonly used to judge RF performance, was improved by up to 5% compared to the basic Si3N4 passivation structure.

7.
Micromachines (Basel) ; 14(6)2023 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-37374812

RESUMO

In this paper, we compared the characteristics of normally-on/off AlGaN/GaN MISHEMTs passivated by an in situ/ex situ SiN layer. The devices passivated by the in situ SiN layer revealed enhanced DC characteristics, such as the drain current of 595 mA/mm (normally-on) and 175 mA/mm (normally-off) with the high on/off current ratio of ~107, respectively, compared with those of the devices passivated by the ex situ SiN layer. The MISHEMTs passivated by the in situ SiN layer also exhibited a much lower increase of dynamic on-resistance (RON) of 4.1% for the normally-on device and 12.8% for the normally-off device, respectively. Furthermore, the breakdown characteristics are greatly improved by employing the in situ SiN passivation layer, suggesting that the in situ SiN passivation layer can remarkably not only suppress the surface-trapping effects, but also decrease the off-state leakage current in the GaN-based power devices.

8.
Alzheimers Dement ; 19(12): 5482-5497, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37218673

RESUMO

INTRODUCTION: Hyperphosphorylation and aggregation of the microtubule-associated protein tau cause the development of tauopathies, such as Alzheimer's disease and frontotemporal dementia (FTD). We recently uncovered a causal link between constitutive serotonin receptor 7 (5-HT7R) activity and pathological tau aggregation. Here, we evaluated 5-HT7R inverse agonists as novel drugs in the treatment of tauopathies. METHODS: Based on structural homology, we screened multiple approved drugs for their inverse agonism toward 5-HT7R. Therapeutic potential was validated using biochemical, pharmacological, microscopic, and behavioral approaches in different cellular models including tau aggregation cell line HEK293 tau bimolecular fluorescence complementation, primary mouse neurons, and human induced pluripotent stem cell-derived neurons carrying an FTD-associated tau mutation as well as in two mouse models of tauopathy. RESULTS: Antipsychotic drug amisulpride is a potent 5-HT7R inverse agonist. Amisulpride ameliorated tau hyperphosphorylation and aggregation in vitro. It further reduced tau pathology and abrogated memory impairment in mice. DISCUSSION: Amisulpride may be a disease-modifying drug for tauopathies.


Assuntos
Doença de Alzheimer , Demência Frontotemporal , Células-Tronco Pluripotentes Induzidas , Tauopatias , Humanos , Camundongos , Animais , Agonismo Inverso de Drogas , Amissulprida/uso terapêutico , Demência Frontotemporal/tratamento farmacológico , Demência Frontotemporal/genética , Células HEK293 , Células-Tronco Pluripotentes Induzidas/metabolismo , Tauopatias/genética , Proteínas tau/metabolismo , Doença de Alzheimer/patologia
9.
Nanomaterials (Basel) ; 13(5)2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36903774

RESUMO

Recently, we reported that device performance degradation mechanisms, which are generated by the γ-ray irradiation in GaN-based metal-insulator-semiconductor high electron mobility transistors (MIS-HEMTs), use extremely thin gate insulators. When the γ-ray was radiated, the total ionizing dose (TID) effects were generated and the device performance deteriorated. In this work, we investigated the device property alteration and its mechanisms, which were caused by the proton irradiation in GaN-based MIS-HEMTs for the 5 nm-thick Si3N4 and HfO2 gate insulator. The device property, such as threshold voltage, drain current, and transconductance varied by the proton irradiation. When the 5 nm-thick HfO2 layer was employed for the gate insulator, the threshold voltage shift was larger than that of the 5 nm-thick Si3N4 gate insulator, despite the HfO2 gate insulator exhibiting better radiation resistance compared to the Si3N4 gate insulator. On the other hand, the drain current and transconductance degradation were less for the 5 nm-thick HfO2 gate insulator. Unlike the γ-ray irradiation, our systematic research included pulse-mode stress measurements and carrier mobility extraction and revealed that the TID and displacement damage (DD) effects were simultaneously generated by the proton irradiation in GaN-based MIS-HEMTs. The degree of the device property alteration was determined by the competition or superposition of the TID and DD effects for the threshold voltage shift and drain current and transconductance deterioration, respectively. The device property alteration was diminished due to the reduction of the linear energy transfer with increasing irradiated proton energy. We also studied the frequency performance degradation that corresponded to the irradiated proton energy in GaN-based MIS-HEMTs using an extremely thin gate insulator.

10.
Exp Mol Med ; 55(3): 612-627, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36914856

RESUMO

Tau oligomers play critical roles in tau pathology and are responsible for neuronal cell death and transmitting the disease in the brain. Accordingly, preventing tau oligomerization has become an important therapeutic strategy to treat tauopathies, including Alzheimer's disease. However, progress has been slow because detecting tau oligomers in the cellular context is difficult. Working toward tau-targeted drug discovery, our group has developed a tau-BiFC platform to monitor and quantify tau oligomerization. By using the tau-BiFC platform, we screened libraries with FDA-approved and passed phase I drugs and identified levosimendan as a potent anti-tau agent that inhibits tau oligomerization. 14C-isotope labeling of levosimendan revealed that levosimendan covalently bound to tau cysteines, directly inhibiting disulfide-linked tau oligomerization. In addition, levosimendan disassembles tau oligomers into monomers, rescuing neurons from aggregation states. In comparison, the well-known anti-tau agents methylene blue and LMTM failed to protect neurons from tau-mediated toxicity, generating high-molecular-weight tau oligomers. Levosimendan displayed robust potency against tau oligomerization and rescued cognitive declines induced by tauopathy in the TauP301L-BiFC mouse model. Our data present the potential of levosimendan as a disease-modifying drug for tauopathies.


Assuntos
Doença de Alzheimer , Tauopatias , Camundongos , Animais , Proteínas tau/metabolismo , Simendana/farmacologia , Simendana/uso terapêutico , Simendana/metabolismo , Tauopatias/tratamento farmacológico , Tauopatias/metabolismo , Tauopatias/patologia , Doença de Alzheimer/metabolismo , Neurônios/metabolismo , Modelos Animais de Doenças , Camundongos Transgênicos
11.
Micromachines (Basel) ; 15(1)2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38258177

RESUMO

In this study, we propose an optimized AlGaN/GaN high-electron-mobility transistor (HEMT) with a considerably improved breakdown voltage. First, we matched the simulated data obtained from a basic T-gate HEMT with the measured data obtained from the fabricated device to ensure the reliability of the simulation. Thereafter, to improve the breakdown voltage, we suggested applying a gate-head extended structure. The gate-head-top and gate-head-bottom lengths of the basic T-gate HEMT were symmetrically extended by 0.2 µm steps up to 1.0 µm. The breakdown voltage of the 1.0 µm extended structure was 52% higher than that of the basic T-gate HEMT. However, the cutoff frequency (fT) and maximum frequency (fmax) degraded. To minimize the degradation of fT and fmax, we additionally introduced a gate-recessed structure to the 1.0 µm gate-head extended HEMT. The thickness of the 25 nm AlGaN barrier layer was thinned down to 13 nm in 3 nm steps, and the highest fT and fmax were obtained at a 6 nm recessed structure. The fT and fmax of the gate-recessed structure improved by 9% and 28%, respectively, with respect to those of the non-gate-recessed structure, and further improvement of the breakdown voltage by 35% was observed. Consequently, considering the trade-off relationship between the DC and RF characteristics, the 1.0 µm gate-head extended HEMT with the 6 nm gate-recessed structure was found to be the optimized AlGaN/GaN HEMT for high-power operations.

12.
Molecules ; 27(24)2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36557874

RESUMO

Tomato is a widely distributed, cultivated, and commercialized vegetable crop. It contains antioxidant constituents including lycopene, tocopherols, vitamin C, γ-aminobutyric acid, phenols, and flavonoids. This study determined the contents of the antioxidant components and activities of the pulp with skin of ten regular, six medium-sized, and two small cherry tomato cultivars at red ripe (BR + 10) stage cultivated in Korea. The relationships among the Hunter color coordinates, the content of each component, and antioxidant activities were measured by Pearson's correlation coefficients. As the a* value increased, the carotenoid and vitamin C contents increased, while the L* value, hue angle and tocopherol content decreased. As the b* value increased, the lycopene and total carotenoid contents decreased, and the flavonoid content in the hydrophilic extracts increased. The contents of vitamin C and total carotenoids including lycopene showed high positive correlations with the DPPH radical scavenging activities of both the lipophilic and hydrophilic extracts. Tocopherols and total phenolics in the hydrophilic and lipophilic extracts were not major positive contributors to the antioxidant activity. These findings suggest the quality standards for consumer requirements and inputs for on-going research for the development of better breeds.


Assuntos
Antioxidantes , Solanum lycopersicum , Antioxidantes/química , Licopeno , Melhoramento Vegetal , Carotenoides/química , Ácido Ascórbico , Tocoferóis , Flavonoides/química , Fenóis/análise , Vitaminas , República da Coreia
13.
Micromachines (Basel) ; 13(11)2022 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-36422387

RESUMO

This study investigates the operational characteristics of AlGaN/GaN high-electron-mobility transistors (HEMTs) by applying a slant-gate structure and drain-side extended field-plate (FP) for improved breakdown voltage. Prior to the analysis of slant-gate-based HEMT, simulation parameters were extracted from the measured data of fabricated basic T-gate HEMTs to secure the reliability of the results. We suggest three different types of slant-gate structures that connect the basic T-gate electrode boundary to the 1st and 2nd SiN passivation layers obliquely. To consider both the breakdown voltage and frequency characteristics, the DC and RF characteristics of various slant-gate structures including the self-heating effect were analyzed by TCAD simulation. We then applied a drain-side extended FP to further increase the breakdown voltage. The maximum breakdown voltage was achieved at the FP length of 0.4 µm. Finally, we conclude that the slant-gate structures can improve breakdown voltage by up to 66% without compromising the frequency characteristics of the HEMT. When the drain-side FP is applied to a slant-gate structure, the breakdown voltage is further improved by up to 108%, but the frequency characteristics deteriorate. Therefore, AlGaN/GaN HEMTs with an optimized slant-gate-based structure can ultimately be a promising candidate for high-power and high-frequency applications.

14.
Arch Pharm Res ; 45(11): 795-805, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36401778

RESUMO

Various factors related to growing conditions can influence the nutritional quality of plants, including vegetable crops, especially the contents of health-promoting phytochemicals. In this study, the phytochemical contents of spinach (Spinacia oleracea) cultivated under greenhouse and open field conditions were comparatively analyzed using a metabolomic approach with Mass Profiler Professional (MPP) software. S. oleracea, which is one of the well-known leafy vegetables belonging to the family Chenopodiaceae, is cultivated worldwide. Although the nutritional value of spinach is high, the phytochemical contents of spinach cultivated under greenhouse and open field conditions have not been comparatively analyzed. Metabolomic analysis of the methanol (MeOH) extracts of greenhouse-cultivated spinach (GS) and open field-cultivated spinach (OFS) using ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS), followed by principal component analysis (PCA) with MPP demonstrated the differential metabolite profiles of GS and OFS. The active compounds 1-3 were isolated and identified using LC-Q-TOF-MS-guided fractionation. Among these, 5,3',4'-trihydroxy-3-methoxy-6,7-methylenedioxyflavone 4'-glucuronide (2) exhibited growth-inhibitory activities against Helicobacter pylori 51. Distribution analysis of compound 2 revealed that the anti-H. pylori compound 2 is an OFS-specific bioactive phytochemical. This indicates that the phytochemical quality of OFS is better than that of GS. These findings will aid in providing vital data for vegetable processors, dieticians, nutritionists, and consumers to select optimal green leafy vegetables.


Assuntos
Compostos Fitoquímicos , Spinacia oleracea , Compostos Fitoquímicos/farmacologia , Espectrometria de Massas , Metabolômica , Folhas de Planta
15.
Taehan Yongsang Uihakhoe Chi ; 83(1): 168-172, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36237347

RESUMO

Tailgut cysts are known to originate from the remnants of the embryonic hindgut. They occur exclusively in the retrorectal and presacral spaces. There have been limited reports of tailgut cysts occurring in the left perirenal space. The present case features a huge tailgut cyst extending from the right perirenal to the perivesical space. We believe that this case report will help to further elucidate the characteristics of perirenal and perivesical tailgut cysts.

16.
J Belg Soc Radiol ; 106(1): 70, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35974891

RESUMO

A vas deferens abscess is a very rare complication of acute vasitis and lower urinary tract infection. A case of vas deferens rupture due to an abscess with severe pelvic inflammation requiring surgical drainage is reported. Teaching Point: Vas deferens abscess rupture is an example of a very rare complication of severe inflammation of the vas deferens.

17.
Int J Med Sci ; 19(7): 1131-1137, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35919819

RESUMO

Although melanogenesis is a defense mechanism against ultraviolet (UV)-induced skin damage, abnormally excessive melanin production causes pigmentation disorders. Tyrosinase, as a key factor for melanin synthesis, plays an important role in inducing skin pigmentation. Therefore, the inhibition of tyrosinase is crucial in preventing skin pigmentation in the cosmetics and medicine fields. However, the majority of well-known tyrosinase inhibitors have been discontinued due to toxic effects on the skin or lack of selectivity and/or stability. In this study, we evaluated possible anti-melanogenic effects of catechin-7-O-α-L-rhamnopyranoside (C7R) isolated from the stem bark of Ulmus parvifolia, to discover a new tyrosinase inhibitor that has both safety and stability. When C7R was pretreated in B16F10 melanoma cells stimulated by α-melanocyte-stimulating hormone, this compound reduced melanin accumulation and murine tyrosinase activity. In line with these results, C7R inhibits tyrosinase purified from a mushroom in vitro like kojic acid and arbutin. Furthermore, C7R exhibited a competitive inhibition on a Lineweaver-Burk plot. Next, the underlying mechanisms of the C7R-mediated tyrosinase inhibitory effect were sought through docking simulation and pharmacophore analysis between tyrosinase residues and C7R. The results of these analyses showed that C7R had binding energy of -14.5kcal/mol, and indicated that C7R interacts with tyrosinase through an aromatic ring and various hydrophobic and hydrogen bonds. Together, our results suggest that C7R can be applied as a novel natural anti-melanogenic agent that inhibits tyrosinase.


Assuntos
Catequina/análogos & derivados , Glicosídeos , Melanoma Experimental , Animais , Catequina/farmacologia , Linhagem Celular Tumoral , Glicosídeos/farmacologia , Melaninas , Melanoma Experimental/tratamento farmacológico , Melanoma Experimental/metabolismo , Camundongos , Monofenol Mono-Oxigenase/metabolismo , alfa-MSH/farmacologia
18.
ACS Omega ; 7(33): 29502-29507, 2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-36033661

RESUMO

Pinus eldarica is a medicinal tree used in traditional herbal medicine for the treatment of bronchial asthma and various skin diseases. As part of our ongoing search for bioactive phytochemicals with novel structures in natural products, we performed a phytochemical analysis of the methanol (MeOH) extract from P. eldarica needles collected in Iran. Phytochemical investigation of the MeOH extract, aided by liquid chromatography-mass spectrometry-based analysis, resulted in the isolation and identification of three labdane-type diterpenes (1-3), including a new and relatively unique norlabdane-type diterpene with a peroxide moiety, eldaricoxide A (1). The chemical structures of the isolated labdane-type diterpenes were elucidated by analyzing the spectroscopic data from 1D and 2D NMR and high-resolution electrospray ionization-mass spectrometry. The absolute configuration of eldaricoxide A (1) was established by employing a computational method, including electronic circular dichroism calculation and specific optical rotation. An anti-Helicobacter pylori test was conducted, where compound 3 exhibited the most potent antibacterial activity against H. pylori strain 51, inducing 72.7% inhibition (MIC50 value of 92 µM), whereas eldaricoxide A (1) exhibited moderate antibacterial activity against H. pylori strain 51, inducing 54.5% inhibition (MIC50 value of 95 µM). These findings demonstrated that the identified bioactive labdane-type diterpenes 1 and 3 can be applied in the development of novel antibiotics against H. pylori for the treatment of gastric and duodenal ulcers.

19.
ACS Omega ; 7(27): 23736-23743, 2022 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-35847243

RESUMO

The fruit of Tetradium ruticarpum, known as Evodiae Fructus, is a traditional herbal medicine used to treat gastric and duodenal ulcers, vomiting, and diarrhea. The traditional usage can be potentially associated with the antibacterial activity of T. ruticarpum fruits against Helicobacter pylori. However, so far, the antibacterial activity of T. ruticarpum fruits and antibacterial components against H. pylori has not been investigated despite the traditional folk use. The current study was conducted to investigate the bioactive chemical components of T. ruticarpum fruits and evaluate their antibacterial activity against H. pylori. Phytochemical investigation of the EtOH extract of T. ruticarpum fruits led to the isolation and identification of nine compounds (1-9), including phellolactone (1), the absolute configuration of which has not yet been determined. The chemical structures of the isolated compounds were elucidated by analyzing the spectroscopic data from one-dimensional (1D) and two-dimensional (2D) NMR and high-resolution electrospray ionization mass spectrometry (HR-ESIMS) experiments. Specifically, the absolute configuration of compound 1 was established by the application of computational methods, including electronic circular dichroism (ECD) calculation and the NOE/ROE-based interproton distance measurement technique via peak amplitude normalization for the improved cross-relaxation (PANIC) method. In the anti-H. pylori activity test, compound 3 showed the most potent antibacterial activity against H. pylori strain 51, with 94.4% inhibition (MIC50 and MIC90 values of 22 and 50 µM, respectively), comparable to that of metronidazole (97.0% inhibition, and MIC50 and MIC90 values of 17 and 46 µM, respectively). Moreover, compound 5 exhibited moderate antibacterial activity against H. pylori strain 51, with 58.6% inhibition (MIC50 value of 99 µM), which was higher than that of quercetin (34.4% inhibition) as a positive control. Based on the bioactivity results, we also analyzed the structure-activity relationship of the anti-H. pylori activity. Conclusion: These findings demonstrated that T. ruticarpum fruits had antibacterial activity against H. pylori and could be used in the treatment of gastric and duodenal ulcers. Meanwhile, the active compound, 1-methyl-2-(8E)-8-tridecenyl-4(1H)-quinolinone (3), identified herein also indicated the potential application in the development of novel antibiotics against H. pylori.

20.
J Belg Soc Radiol ; 106(1): 24, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35581984

RESUMO

Teaching Point: Radiologists need to be familiar with that ovarian vein thrombosis can occur as a complication of urinary tract infection. Ovarian vein thrombosis is a rare disease in which a majority of cases occur during the postpartum period. There are few case reports for ovarian vein thrombosis associated with urinary tract infection in non-postpartum women. We report a case of ovarian vein thrombosis incidentally diagnosed on computed tomography in a patient with symptoms of urinary tract infection.

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