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1.
Eur Arch Otorhinolaryngol ; 280(12): 5251-5258, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37210462

RESUMO

PURPOSE: To observe vestibular impairment patterns in patients with Ramsay Hunt syndrome with dizziness (RHS_D) and sudden sensorineural hearing loss with dizziness (SSNHL_D) using hierarchical cluster analysis (HCA) to interpret results with possible mechanisms. METHODS: The data of 30 RHS_D and 81 SSNHL_D patients from January 2017 to August 2022 in a single tertiary referral center were retrospectively analyzed. Video head impulse test (vHIT) and vestibular evoked myogenic potential (VEMP) were used for vestibular analysis of peripheral vestibular organs, and the results of vHIT and VEMP were analyzed. HCA was used to analyze vestibular impairment patterns. RESULTS: In RHS_D patients, the lateral semicircular canal (LSCC) was the most impaired semicircular canal (SCC), followed by the anterior semicircular canal (ASCC) and the posterior semicircular canal (PSCC), and the utricle was more impaired than the saccule. In SSNHL_D patients, the PSCC was the most impaired SCC, followed by the LSCC and the ASCC, and the utricle was more impaired than the saccule. In HCA of RHS_D patients, the ASCC and utricle were initially clustered, followed by the LSCC, PSCC and saccule in order. In the HCA of SSNHL_D patients, the PSCC was solely merged and independently clustered. CONCLUSION: There were different patterns of vestibular impairments between RHS_D and SSNHL_D patients. The vestibular analysis and HCA results of SSNHL_D showed tendency of skip lesion, which could be explained by vascular pathophysiology.


Assuntos
Perda Auditiva Neurossensorial , Perda Auditiva Súbita , Herpes Zoster da Orelha Externa , Potenciais Evocados Miogênicos Vestibulares , Humanos , Tontura , Herpes Zoster da Orelha Externa/complicações , Herpes Zoster da Orelha Externa/diagnóstico , Estudos Retrospectivos , Vertigem , Perda Auditiva Neurossensorial/diagnóstico , Canais Semicirculares , Perda Auditiva Súbita/diagnóstico
2.
Int J Mol Sci ; 24(5)2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36901915

RESUMO

Continuous consumption of high-calorie meals causes lipid accumulation in the liver and liver damage, leading to non-alcoholic fatty liver disease (NAFLD). A case study of the hepatic lipid accumulation model is needed to identify the mechanisms underlying lipid metabolism in the liver. In this study, the prevention mechanism of lipid accumulation in the liver of Enterococcus faecalis 2001 (EF-2001) was extended using FL83B cells (FL83Bs) and high-fat diet (HFD)-induced hepatic steatosis. EF-2001 treatment inhibited the oleic acid (OA) lipid accumulation in FL83B liver cells. Furthermore, we performed lipid reduction analysis to confirm the underlying mechanism of lipolysis. The results showed that EF-2001 downregulated proteins and upregulated AMP-activated protein kinase (AMPK) phosphorylation in the sterol regulatory element-binding protein 1c (SREBP-1c) and AMPK signaling pathways, respectively. The effect of EF-2001 on OA-induced hepatic lipid accumulation in FL83Bs enhanced the phosphorylation of acetyl-CoA carboxylase and reduced the levels of lipid accumulation proteins SREBP-1c and fatty acid synthase. EF-2001 treatment increased the levels of adipose triglyceride lipase and monoacylglycerol during lipase enzyme activation, which, when increased, contributed to increased liver lipolysis. In conclusion, EF-2001 inhibits OA-induced FL83B hepatic lipid accumulation and HFD-induced hepatic steatosis in rats through the AMPK signaling pathway.


Assuntos
Lipólise , Hepatopatia Gordurosa não Alcoólica , Ratos , Animais , Proteínas Quinases Ativadas por AMP/metabolismo , Dieta Hiperlipídica , Enterococcus faecalis/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Temperatura Alta , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Metabolismo dos Lipídeos , Transdução de Sinais , Lipídeos/farmacologia
3.
Curr Issues Mol Biol ; 44(5): 1928-1940, 2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-35678660

RESUMO

The proliferation and migration of vascular smooth muscle cells (VSMCs) are important factors in the occurrence of cardiovascular diseases, such as blood flow abnormalities, stroke and atherosclerosis. Evening primrose, known as Oenothera biennis, is a plant native to Korea that exerts physiological activities, such as antioxidant effects, the inhibition of lipid accumulation and the prevention of muscle atrophy. However, the function of evening primrose stem (EVP) in the regulation of VSMC proliferation and migration and the underlying mechanisms have not been identified. In this study, the effect of EVP on the platelet-derived growth factor (PDGF)-induced proliferation and migration of VSMCs was investigated. The results show that PDGF-BB-induced proliferation of VSMCs was inhibited by EVP at concentrations of 25, 50 or 100 µg/mL in a concentration-dependent manner, and a migration assay showed that EVP inhibited cell migration. Cell cycle analysis was performed to confirm the mechanism by which cell proliferation and migration was inhibited. The results indicate that proteins involved in the cell cycle, such as cyclin, CDK and phosphorylated Rb, were downregulated by EVP at concentrations of 100 µg/mL, thereby increasing the proportion of cells in the G0/G1 phase and inhibiting cell cycle progression. In the PDGF receptor (PDGFR) signaling pathway, phosphorylation of the PDGFR was inhibited by EVP at concentrations of 100 µg/mL, and PLCγ phosphorylation was also decreased. The PDGF-BB-induced effect of EVP on the proliferation of VSMCs involved the inhibition of Akt phosphorylation and the reduction in the phosphorylation of MAPK proteins such as ERK, P38 and JNK. In conclusion, the results demonstrate that EVP inhibited PDGF-BB-induced VSMC proliferation and migration by regulating cell-cycle-related proteins.

4.
Otolaryngol Head Neck Surg ; 170(2): 515-521, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37787037

RESUMO

OBJECTIVE: To evaluate the older adults with chronic dizziness using the Barany Society's presbyvestibulopathy (PVP) diagnostic criteria and to assess the clinical usability of the criteria. STUDY DESIGN: Retrospective study. SETTING: Single tertiary medical center. METHODS: Among a total of 1964 patients aged 60 years or older, 55 patients who had symptoms suitable for the PVP criteria and who underwent all 3 vestibular function tests were analyzed. Of these 55 patients, 13 patients were diagnosed with PVP based on the peripheral vestibular hypofunction criteria; the remaining 42 patients were categorized as patients without PVP. RESULTS: In both patients with PVP and patients without PVP, postural imbalance or unsteadiness was the most frequently reported vestibular symptom. The rotatory chair test contributed the most to the quantitative diagnosis of PVP (6 of 13), followed by the caloric response test (3 of 13) and video head impulse test (vHIT; 2 of 13). When we included the presence of catch-up saccades in addition to the vHIT gain in the diagnostic criteria, 5 patients without PVP were additionally diagnosed with PVP. Furthermore, when accounting for the inclusion of catch-up saccades, patients who experienced recurrent falls demonstrated a significantly higher rate of impairments in the lateral and posterior semicircular canals according to the multivariate analysis. CONCLUSION: Considering the catch-up saccades in addition to vHIT gain seemed to contribute to the diagnosis of PVP and prediction of recurrent fall risks in older adults. Further studies are needed to solidify the diagnostic criteria for PVP.


Assuntos
Tontura , Testes de Função Vestibular , Humanos , Idoso , Tontura/diagnóstico , Tontura/etiologia , Estudos Retrospectivos , Testes Calóricos , Teste do Impulso da Cabeça , Canais Semicirculares , Reflexo Vestíbulo-Ocular/fisiologia
5.
Sci Rep ; 14(1): 6263, 2024 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-38491103

RESUMO

Psychological stress and intestinal leakage are key factors in atopic dermatitis (AD) recurrence and exacerbation. Here, we demonstrate the mechanism underlying bacterial translocation across intestinal epithelial barrier damaged due to stress and further aggravation of trimellitic anhydride (TMA)-induced itch, which remain unclear, in AD mice. Immobilization (IMO) stress exacerbated scratching bouts and colon histological damage, and increased serum corticosterone and lipopolysaccharide (LPS). Orally administered fluorescein isothiocyanate (FITC)-dextran and surgically injected (into the colon) Cy5.5-conjugated LPS were detected in the serum and skin after IMO stress, respectively. The relative abundance of aerobic or facultative anaerobic bacteria was increased in the colon mucus layer, and Lactobacillus murinus, E. coli, Staphylococcus nepalensis, and several strains of Bacillus sp. were isolated from the spleens and mesenteric lymph nodes. Oral antibiotics or intestinal permeability blockers, such as lubiprostone (Lu), 2,4,6-triaminopyrimidine (TAP) and ML-7, inhibited IMO stress-associated itch; however, it was reinduced through intradermal or i.p. injection of LPS without IMO stress. I.p. injection of TAK-242 (resatorvid), a TLR4 inhibitor, abrogated IMO stress-associated itch, which was also confirmed in TLR4-KO mice. IMO stress alone did not cause itch in naïve mice. IMO stress-induced itch aggravation in TMA-treated AD mice might be attributed to the translocation of gut-derived bacterial cells and LPS, which activates peripheral TLR4 signaling.


Assuntos
Dermatite Atópica , Receptor 4 Toll-Like , Animais , Camundongos , Dermatite Atópica/metabolismo , Dermatite Atópica/patologia , Modelos Animais de Doenças , Escherichia coli , Lipopolissacarídeos/metabolismo , Prurido/induzido quimicamente , Receptor 4 Toll-Like/metabolismo
6.
Otolaryngol Head Neck Surg ; 169(6): 1573-1581, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37418229

RESUMO

OBJECTIVE: To investigate the impairment patterns in peripheral vestibular organs in sudden sensorineural hearing loss (SSNHL) with and without vertigo. STUDY DESIGN: Retrospective study. SETTING: Single tertiary medical center. METHODS: Data from 165 SSNHL patients in a tertiary referral center from January 2017 to December 2022 were retrospectively analyzed. All patients underwent a video head impulse test, vestibular evoked myogenic potential test, and pure-tone audiometry. Hierarchical cluster analysis was performed to investigate vestibular impairment patterns. The prognosis of the hearing was determined using American Academy of Otolaryngology-Head and Neck Surgery recommendations. RESULTS: After excluding patients with vestibular schwannoma and Meniere's disease, 152 patients were included in this study. A total of 73 of 152 patients were categorized as SSNHL with vertigo (SSNHL_V) and showed an independent merge of the posterior semicircular canal (PSCC) in cluster analysis. A total of 79 of 152 patients were categorized as SSNHL without vertigo (SSNHL_N) and showed an independent merge of saccule in cluster analysis. The PSCC (56.2%) and saccule (20.3%) were the most frequently impaired vestibular organs in SSNHL_V and SSNHL_N, respectively. In terms of prognosis, 106 of 152 patients had partial/no recovery and showed an independent merge of the PSCC in cluster analysis. A total of 46 of 152 patients had a complete recovery and showed an independent merge of the saccule in cluster analysis. CONCLUSION: A tendency of isolated PSCC dysfunction was seen in SSNHL_V and partial/no recovery. A tendency of isolated saccular dysfunction was seen in SSNHL_N and complete recovery. Different treatments might be needed in SSNHL depending on the presence of vertigo.


Assuntos
Perda Auditiva Neurossensorial , Perda Auditiva Súbita , Vestíbulo do Labirinto , Humanos , Estudos Retrospectivos , Vertigem/etiologia , Perda Auditiva Neurossensorial/complicações , Perda Auditiva Súbita/diagnóstico , Perda Auditiva Súbita/etiologia , Audiometria de Tons Puros
7.
Plants (Basel) ; 11(4)2022 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-35214881

RESUMO

Pueraria lobata (Willd.) Ohwi. is a widely used medicinal plant in Korea, China, and Japan. The flower of P. lobata (Puerariae Flos) contains various bioactive substances such as triterpenoidal saponins and isoflavonoids. In this study, we developed a quantitative analysis of the isoflavones of Puerariae Flos by quantitative proton nuclear magnetic resonance (qHNMR) spectroscopy using the internal calibrant (IC). From the qHNMR results, the isoflavone content was found to be 7.99% and 10.57% for the MeOH sonication extract (PLs) and the MeOH reflux extract (PLr) of Puerariae Flos, respectively. The quantified isoflavone content was validated using the conventional analytical method, high-performance liquid chromatography with ultraviolet detection (HPLC-UV). The present study shows that validated qHNMR spectroscopy is a reliable method for quantifying and standardizing the isoflavone content in Puerariae Flos.

8.
Plants (Basel) ; 11(23)2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36501346

RESUMO

Increasing scientific evidence has demonstrated that the roots of Polygala tenuifolia Willd. have pharmacological effects related to anti-inflammation. Therefore, the aim of this study is to investigate the chemical constituents from P. tenuifolia roots as anti-inflammatory drug candidates. In the present work, twenty-three compounds were isolated from P. tenuifolia roots, including three saponins (1-3), ten phenylpropanoid sucrose esters (4-12), one benzoic acid sugar ester derivative (13), four xanthones (14-17), two hydroxy benzophenone derivatives (18 and 19), two phenolic derivatives (20 and 21), and two ionones (22 and 23). All isolates were tested for their inhibitory effects of LPS-stimulated NO and PGE2 production in RAW 264.7 macrophages. Among these, 3-O-(3,4,5-trimethoxy-cinnamoyl),6'-O-(p-methoxybenzoyl) sucrose ester (TCMB; 11) together with compounds 3 and 21 exhibited significant inhibitory effects on NO production, while TCMB and compounds 17, 19, and 21 showed strong inhibitory effects on PGE2 production. Specifically, TCMB (11) downregulated the protein levels of iNOS and COX-2 in LPS-induced RAW 264.7 macrophages. In addition, TCMB (11) dose-dependently diminished the relative mRNA expression levels of iNOS, PGE2, and proinflammatory cytokines (TNF-α, IL-1ß, and IL-6). A molecular docking study showed that TCMB (11) has strong binding affinities with iNOS and COX-2.

9.
J Ginseng Res ; 46(5): 657-665, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36090680

RESUMO

Background: Sarcopenia is a new and emerging risk factor aggravating the quality of life of elderly population. Because Korean Red Ginseng (RG) is known to have a great effect on relieving fatigue and enhancing physical performance, it is invaluable to examine its potential as an anti-sarcopenic drug. Methods: Anti-sarcopenic effect of non-saponin fraction of Korean Red Ginseng (RGNS) was evaluated in C2C12 myoblasts treated with C2-ceramide to induce senescence phenotypes, and 22-month-old mice fed with chow diet containing 2% RGNS (w/w) for 4 further months. Results: The RGNS treatment significantly alleviated cellular senescence indicated by intracellular lipid accumulation, increased amount of lysosomal ß-galactosidase, and reduced proliferative capacity in C2C12 myoblasts. This effect was not observed with saponin fraction. In an aged mouse, the 4-month-RGNS diet significantly improved aging-associated loss of muscle mass and strength, assessed by the weights of hindlimb skeletal muscles such as tibialis anterior (TA), extensor digitorum longus (EDL), gastrocnemius (GN) and soleus (SOL), and the cross-sectional area (CSA) of SOL muscle, and the behaviors in grip strength and hanging wire tests, respectively. During the same period, an aging-associated shift of fast-to slow-twitch muscle in SOL muscle was also retarded by the RGNS treatment. Conclusions: These findings suggested that the long-term diet of RGNS significantly prevented aging-associated muscle atrophy and reduced physical performance, and thus RGNS has a strong potential to be developed as a drug that prevents or improves sarcopenia.

10.
Antioxidants (Basel) ; 11(2)2022 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-35204176

RESUMO

The rhizomes of Alpinia galanga (Thai ginger) have been used extensively as a spice in Southeast Asian and Arabian cuisines and reported to possess a wide range of biological properties, such as antioxidant, antimicrobial, and antibacterial. However, the specific molecular and cellular mechanisms underlying the anti-tumor effects induced by Thai ginger and its corresponding active compounds have been poorly characterized. We found that upon EtOH extraction, Thai ginger extract exhibits cytotoxic activity (IC50 < 10 µg/mL) and triggers cell death via caspase-dependent apoptosis in human ovarian cancer cells. Among the three major compounds isolated from the extract, 1'-acetoxyeugenol acetate (AEA) exhibited potent cytotoxic activity in human ovarian cancer cells, SKOV3 and A2780. AEA induced apoptotic cell death through the activation of caspases-3 and -9. Notably, AEA enhanced the intracellular levels of reactive oxygen species (ROS), and the application of an antioxidant markedly reversed AEA-induced apoptosis of ovarian cancer cells. The knockdown of p47phox, a subunit of NADPH oxidase, suppressed both the pro-apoptotic and ROS-inducing effects of AEA. Additionally, the activation of the mitogen-activated protein kinase (MAPK) pathway by AEA through ROS regulation was found to be involved in AEA-induced apoptosis. Altogether, these results suggest that AEA exhibits potent apoptosis-inducing activity through the activation of the intrinsic pathway via ROS-mediated MAPK signaling in human ovarian cancer cells.

11.
Nutrients ; 14(6)2022 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-35334965

RESUMO

Increasing consumption of food with high caloric density and a sedentary lifestyle have influenced the increasing obesity prevalence worldwide. The recent pandemic has contributed to this problem. Obesity refers to a state in which lipid accumulates excessively in adipocytes and adipose tissues. Dried heat-killed Enterococcus faecalis (EF-2001) prevents allergic mechanisms, inflammation, and tumor progression. In the present study, we investigated the effects of EF-2001 on high fat diet (HFD)-induced obese rats. The degree of obesity in experimental rats was reduced after 6 weeks of oral administration of 3 mg/kg or 30 mg/kg dosages of EF-2001, indicating regulating effects in rats with HFD-induced obesity. We found that EF-2001 decreased the amounts of total cholesterol, triglyceride, and non-high density lipoprotein (HDL) in HFD-induced obese rats. The effects of EF-2001 on 3T3-L1 adipocytes stained with Oil red O stain are shown in reductions of lipid accumulation, respectively. In addition, we examined the relationships between EF-2001 treatment and mechanisms for the insulin signaling of adipogenesis in 3T3-L1 cells. EF-2001 induced down-regulation in phosphorylation of Erk, JNK, and Akt through the inhibition of insulin receptor phosphorylation. EF-2001 inhibits the expressions of C/EBP-α and PPAR-γ, a lipid metabolism-related transcription factor through confocal microscope observation and Western blot on 3T3-L1 adipocytes and HFD-induced obese rats. Based on our results, intake of EF-2001 significantly prevented HFD-induced obesity in rats through inhibition of C/EBP-α and PPAR-γ in the insulin signaling pathway on lipid accumulation.


Assuntos
Adipogenia , Dieta Hiperlipídica , Animais , Dieta Hiperlipídica/efeitos adversos , Enterococcus faecalis , Temperatura Alta , Insulina/farmacologia , Obesidade/etiologia , Obesidade/metabolismo , Obesidade/prevenção & controle , PPAR gama/metabolismo , Ratos , Transdução de Sinais , Triglicerídeos/farmacologia
12.
Life Sci ; 307: 120912, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-36037872

RESUMO

Menaquinone (MK)-7 is a vitamin K2 analog that functions as a cofactor of γ-glutamyl carboxylase involved in the activation of vitamin K (VK)-dependent proteins. The present study aimed to evaluate the effect of MK-7 on memory and cognitive function in aged C57BL/6 mice. Eighteen-month-old mice were raised for a further 4 months, fed on a standard or calcium-rich diet (3 % [w/w]), and were orally given MK-7 (40 and 400 µg/day/mouse) five times per week during the same period. The Morris water maze (MWM) test was performed at 19 and 22 months. The aged mice showed noticeable memory declines in the MWM test at all time points compared with 6-week-old mice, and this memory loss was significantly restored by the daily administration of high-dose MK-7 for 4 months. MK-7 administration also improved micro-computed tomography-based cerebrovascular calcification and aging-associated declines in growth arrest-specific 6, total and carboxylated matrix Gla proteins, and ganglioside levels in the brain of aged mice. It serologically reduced phosphorous levels in the blood, but not the urea, cholesterol, and calcium. Taken together, the long-term administration of MK-7 significantly improved age-related memory and cognitive impairments, possibly through inhibition of cerebrovascular calcification in aged mice, indicating that it can be used to develop new drugs for improving memory and cognitive function in older adults.


Assuntos
Calcinose , Cálcio , Animais , Colesterol , Gangliosídeos , Transtornos da Memória/tratamento farmacológico , Camundongos , Camundongos Endogâmicos C57BL , Ureia , Vitamina K , Vitamina K 2/análogos & derivados , Vitamina K 2/farmacologia , Vitamina K 2/uso terapêutico , Microtomografia por Raio-X
13.
Phys Med Biol ; 65(21): 215026, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-33151909

RESUMO

In this paper, we propose a method for compositing a synthetic mammogram (SM) from digital breast tomosynthesis (DBT) slice images. The method consists of four parts. The first part is image reconstruction of DBT from the acquired projection data by use of backprojection-filtration (BPF) algorithm with a low-frequency boosting scheme and a high-density object reduction technique embedded. Also, a few expectation-maximization (EM) iterations have been additively implemented on top of the BPF algorithm to prepare a separate volume image. The second is generating three kinds of intermediate SMs. A forward projection image and a linear structure weighted forward projection image were computed. A maximum intensity projection of the BPF reconstructed volume image was also generated. The third part is integrating three intermediate SMs. The last is the post-processing of the SM. We scanned two physical phantoms in a prototype DBT scanner, and we have evaluated the performance of the proposed method. We also performed a clinical data study by use of 30 patient data who went through both DBT and digital mammography (DM) scans. Three experienced radiologists have read the SMs generated by several component techniques and also read the DM of each patient, and evaluated the generated SMs. The experimental phantom study and the clinical reader study consistently demonstrated the usefulness of the proposed method.


Assuntos
Artefatos , Processamento de Imagem Assistida por Computador/métodos , Mamografia , Intensificação de Imagem Radiográfica/métodos , Algoritmos , Neoplasias da Mama/diagnóstico por imagem , Feminino , Humanos , Imagens de Fantasmas , Razão Sinal-Ruído
14.
Nat Prod Res ; 33(6): 814-821, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29224362

RESUMO

Three acacetin triglycosides (compounds 1, 2 and 3) were isolated from the herbs of Elsholtzia ciliata (Labiatae). The structure were identified as 7-O-ß-D-glucopyranosyl-(1 â†’ 2)[α-L-rhamnopyranosyl-(1 â†’ 6)]-ß-D-glucopyranoside (compound 1), 7-O-(6-O-acetyl)-ß-D-glucopyranosyl-(1 â†’ 2)[α-L-rhamnopyranosyl-(1 â†’ 6)]-ß-D-glucopyranoside (compound 2) and 7-O-(6-O-acetyl)-ß-D-glucopyranosyl-(1 â†’ 2)[(4-O-acetyl)-α-L-rhamnopyranosyl-(1 â†’ 6)]-ß-D-glucopyranoside (compound 3) of acacetin. The structures of these compounds were determined on the basis of 2D-NMR spectroscopic data. Compound 3 has not been isolated from a natural source. In addition, the three compounds were quantitatively analysed by HPLC. Acetylcholinesterase (AChE) inhibition activity was assayed to find anti-Alzheimer's activity, since this enzyme increases the concentration of acetylcholine (ACh), a neurotransmitter, responsible for brain's memory. Acacetin, the aglycone of the three compounds, exhibited a potent anti-cholinesterase activity (IC50, 50.33 ± 0.87), though its glycosides (1, 2 and 3) were less active. HPLC analysis demonstrated that the three compounds were contained in the MeOH extract in the order of compounds 2 (12.63 mg/g extract) > 3 (3.10 mg/g) > 1 (2.92 mg/g).


Assuntos
Inibidores da Colinesterase/química , Flavonas/química , Glicosídeos/química , Lamiaceae/química , Acetilcolinesterase , Inibidores da Colinesterase/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Flavonas/isolamento & purificação , Glicosídeos/isolamento & purificação , Espectroscopia de Ressonância Magnética , Estrutura Molecular , República da Coreia
15.
Med Phys ; 44(2): 417-425, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28032909

RESUMO

PURPOSE: Nonlinear pre-reconstruction processing of the projection data in computed tomography (CT) where accurate recovery of the CT numbers is important for diagnosis is usually discouraged, for such a processing would violate the physics of image formation in CT. However, one can devise a pre-processing step to enhance detectability of lesions in digital breast tomosynthesis (DBT) where accurate recovery of the CT numbers is fundamentally impossible due to the incompleteness of the scanned data. Since the detection of lesions such as micro-calcifications and mass in breasts is the purpose of using DBT, it is justified that a technique producing higher detectability of lesions is a virtue. METHODS: A histogram modification technique was developed in the projection data domain. Histogram of raw projection data was first divided into two parts: One for the breast projection data and the other for background. Background pixel values were set to a single value that represents the boundary between breast and background. After that, both histogram parts were shifted by an appropriate amount of offset and the histogram-modified projection data were log-transformed. Filtered-backprojection (FBP) algorithm was used for image reconstruction of DBT. To evaluate performance of the proposed method, we computed the detectability index for the reconstructed images from clinically acquired data. RESULTS: Typical breast border enhancement artifacts were greatly suppressed and the detectability of calcifications and masses was increased by use of the proposed method. Compared to a global threshold-based post-reconstruction processing technique, the proposed method produced images of higher contrast without invoking additional image artifacts. CONCLUSIONS: In this work, we report a novel pre-processing technique that improves detectability of lesions in DBT and has potential advantages over the global threshold-based post-reconstruction processing technique. The proposed method not only increased the lesion detectability but also reduced typical image artifacts pronounced in conventional FBP-based DBT.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Mamografia/métodos , Algoritmos , Artefatos , Neoplasias da Mama/diagnóstico por imagem , Calcinose/diagnóstico por imagem , Desenho de Equipamento , Humanos , Mamografia/instrumentação , Modelos Anatômicos , Imagens de Fantasmas
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