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1.
Audiol Neurootol ; 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38452739

RESUMO

OBJECTIVES: To evaluate the vestibulo-ocular reflex (VOR) using the video head impulse test (vHIT) as a vestibular function assessment method in patients with unilateral chronic otitis media (COM). METHODS: Twenty-eight patients with unilateral COM scheduled for middle ear surgery, including 12 males and 16 females with a mean age of 54.5 years, successfully underwent preoperative vHIT. vHIT variables, including VOR gain, VOR gain asymmetry, and the incidence of corrective saccades, were compared between the ipsilesional and contralesional ears. RESULTS: Ten (35.7%) patients reported varying degrees of disequilibrium or lightheadedness. The VOR gain in the ipsilesional and contralesional ears were 1.01 ± 0.10 and 1.04 ± 0.11, 0.97 ± 0.12 and 0.94 ± 0.13, and 0.97 ± 0.13 and 1.04 ± 0.15 in the horizontal canal (HC), anterior canal (AC), and posterior canal (PC), respectively. The average VOR gains in the ipsilesional ears were within the predefined range of normal values; however, the gains in HC and PC significantly decreased compared with those in contralesional ears (p=0.038 in HC and p=0.015 in PC). The prevalence of corrective saccades, including overt and/or covert saccades, did not differ significantly between the two ears. CONCLUSION: This study assessed the pathophysiology of the inner ear affected by chronic middle ear infection by quantitatively comparing the VOR using vHIT. It demonstrated that vHIT can be a practical assessment of vestibular function in patients with COM.

2.
Dement Neurocogn Disord ; 23(1): 22-29, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38362054

RESUMO

Background and Purpose: Alzheimer's disease (AD) is a neurodegenerative disease characterized by a progressive decline in cognition and performance of daily activities. Recent studies have attempted to establish the relationship between AD and sleep. It is believed that patients with AD pathology show altered sleep characteristics years before clinical symptoms appear. This study evaluated the differences in sleep characteristics between cognitively asymptomatic patients with and without some amyloid burden. Methods: Sleep characteristics of 76 subjects aged 60 years or older who were diagnosed with subjective cognitive decline (SCD) but not mild cognitive impairment (MCI) or AD were measured using Fitbit® Alta HR, a wristwatch-shaped wearable device. Amyloid deposition was evaluated using brain amyloid plaque load (BAPL) and global standardized uptake value ratio (SUVR) from fluorine-18 florbetaben positron emission tomography. Each component of measured sleep characteristics was analyzed for statistically significant differences between the amyloid-positive group and the amyloid-negative group. Results: Of the 76 subjects included in this study, 49 (64.5%) were female. The average age of the subjects was 70.72±6.09 years when the study started. 15 subjects were classified as amyloid-positive based on BAPL. The average global SUVR was 1.598±0.263 in the amyloid-positive group and 1.187±0.100 in the amyloid-negative group. Time spent in slow-wave sleep (SWS) was significantly lower in the amyloid-positive group (39.4±13.1 minutes) than in the amyloid-negative group (49.5±13.1 minutes) (p=0.009). Conclusions: This study showed that SWS is different between the elderly SCD population with and without amyloid positivity. How SWS affects AD pathology requires further research.

3.
J Alzheimers Dis ; 97(1): 193-204, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38108349

RESUMO

BACKGROUND: Subjective cognitive decline (SCD) refers to the self-reported persistent cognitive decline despite normal objective testing, increasing the risk of dementia compared to cognitively normal individuals. OBJECTIVE: This study aims to investigate the attributes of SCD patients who demonstrated memory function improvement. METHODS: In this prospective study of SCD, a total of 120 subjects were enrolled as part of a multicenter cohort study aimed at identifying predictors for the clinical progression to mild cognitive impairment or dementia (CoSCo study). All subjects underwent 18F-florbetaben PET and brain MRI scans at baseline and annual neuropsychological tests. At the 24-month follow-up, we classified SCD patients based on changes in memory function, the z-score of the Seoul verbal learning test delayed recall. RESULTS: Of the 120 enrolled patients, 107 successfully completed the 24-month follow-up assessment. Among these, 80 patients (74.8%) with SCD exhibited memory function improvements. SCD patients with improved memory function had a lower prevalence of coronary artery disease at baseline and performed better in the trail-making test part B compared to those without improvement. Anatomical and biomarker analysis showed a lower frequency of amyloid PET positivity and larger volumes in the left and right superior parietal lobes in subjects with improved memory function. CONCLUSIONS: Our prospective study indicates that SCD patients experiencing memory improvement over a 24-month period had a lower amyloid burden, fewer cardiovascular risk factors, and superior executive cognitive function. Identifying these key factors associated with cognitive improvement may assist clinicians in predicting future memory function improvements in SCD patients.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Demência , Humanos , Estudos Longitudinais , Estudos de Coortes , Estudos Prospectivos , Disfunção Cognitiva/epidemiologia , Neuroimagem , Testes Neuropsicológicos , Doença de Alzheimer/psicologia
4.
Biomacromolecules ; 24(6): 2633-2642, 2023 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-37075205

RESUMO

Recently, the desire for a safe and effective method for skin whitening has been growing in the cosmetics industry. Commonly used tyrosinase-inhibiting chemical reagents exhibit side effects. Thus, recent studies have focused on performing melanin decolorization with enzymes as an alternative due to the low toxicity of enzymes and their ability to decolorize melanin selectively. Herein, 10 different isozymes were expressed as recombinant lignin peroxidases (LiPs) from Phanerochaete chrysosporium (PcLiPs), and PcLiP isozyme 4 (PcLiP04) was selected due to its high stability and activity at pH 5.5 and 37 °C, which is close to human skin conditions. In vitro melanin decolorization results indicated that PcLiP04 exhibited at least 2.9-fold higher efficiency than that of well-known lignin peroxidase (PcLiP01) in a typical human skin-mimicking environment. The interaction force between melanin films measured by a surface forces apparatus (SFA) revealed that the decolorization of melanin by PcLiP04 harbors a disrupted structure, possibly interrupting π-π stacking and/or hydrogen bonds. In addition, a 3D reconstructed human pigmented epidermis skin model showed a decrease in melanin area to 59.8% using PcLiP04, which suggests that PcLiP04 exhibits a strong potential for skin whitening.


Assuntos
Melaninas , Phanerochaete , Humanos , Peroxidases , Pele , Epiderme , Lignina
5.
Dement Neurocogn Disord ; 21(4): 147-161, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36407288

RESUMO

Background and Purpose: Subjective cognitive decline (SCD) refers to the self-perception of cognitive decline with normal performance on objective neuropsychological tests. SCD, which is the first help-seeking stage and the last stage before the clinical disease stage, can be considered to be the most appropriate time for prevention and treatment. This study aimed to compare characteristics between the amyloid positive and amyloid negative groups of SCD patients. Methods: A cohort study to identify predictors for the clinical progression to mild cognitive impairment (MCI) or dementia from subjective cognitive decline (CoSCo) study is a multicenter, prospective observational study conducted in the Republic of Korea. In total, 120 people aged 60 years or above who presented with a complaint of persistent cognitive decline were selected, and various risk factors were measured among these participants. Continuous variables were analyzed using the Wilcoxon rank-sum test, and categorical variables were analyzed using the χ2 test or Fisher's exact test. Logistic regression models were used to assess the predictors of amyloid positivity. Results: The multivariate logistic regression model indicated that amyloid positivity on PET was related to a lack of hypertension, atrophy of the left temporal lateral and entorhinal cortex, low body mass index, low waist circumference, less body and visceral fat, fast gait speed, and the presence of the apolipoprotein E ε4 allele in amnestic SCD patients. Conclusions: The CoSCo study is still in progress, and the authors aim to identify the risk factors that are related to the progression of MCI or dementia in amnestic SCD patients through a two-year follow-up longitudinal study.

6.
ACS Appl Mater Interfaces ; 14(9): 11465-11473, 2022 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-35196006

RESUMO

The pulp and paper manufacturers generate approximately 50 million metric tons of lignin per annum, most of which has been abandoned or incinerated because of lignin's recalcitrant nature. Here, we report bias-free photoelectrochemical (PEC) oxidation of lignin coupled with asymmetric hydrogenation of C═C bonds. The PEC platform consists of a hematite (α-Fe2O3) photoanode and a silicon photovoltaic-wired mesoporous indium tin oxide (Si/mesoITO) photocathode. We substantiate a new function of photoelectroactivated α-Fe2O3 to extract electrons from lignin. The extracted electrons are transferred to the Si/mesoITO photocathode for regenerating synthetic nicotinamide cofactor analogues (mNADHs). We demonstrate that the reduction kinetics of mNAD+s depend on their reduction peak potentials. The regenerated mNADHs activate ene-reductases from the old yellow enzyme (OYE) family, which catalyze enantioselective reduction of α,ß-unsaturated hydrocarbons. This lignin-fueled biocatalytic PEC system exhibits an excellent OYE's turnover frequency and total turnover number for photobiocatalytic trans-hydrogenation through cofactor regeneration. This work presents the first example of PEC regeneration of mNADHs and opens up a sustainable route for bias-free chemical synthesis using renewable lignin waste as an electron feedstock.

7.
Foods ; 10(7)2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34359519

RESUMO

Improved methods are needed to extend the shelf life of strawberry fruits. The objective of this study was to determine the postharvest physiological mechanism of high-CO2 treatment in strawberries. Harvested strawberries were stored at 10 °C after 3 h of exposure to a treatment with 30% CO2 or air. Pectin and gene expression levels related to cell wall degradation were measured to assess the high-CO2 effects on the cell wall and lipid metabolism. Strawberries subjected to high-CO2 treatment presented higher pectin content and firmness and lower decay than those of control fruits. Genes encoding cell wall-degrading enzymes (pectin methylesterase, polygalacturonase, and pectate lyase) were downregulated after high-CO2 treatment. High-CO2 induced the expression of oligogalacturonides, thereby conferring defense against Botrytis cinerea in strawberry fruits, and lowering the decay incidence at seven days after its inoculation. Our findings suggest that high-CO2 treatment can maintain strawberry quality by reducing decay and cell wall degradation.

8.
Enzyme Microb Technol ; 148: 109803, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34116764

RESUMO

The development of a lignin peroxidase (LiP) that is thermostable even under acidic pH conditions is a main issue for efficient enzymatic lignin degradation due to reduced repolymerization of free phenolic products at acidic pH (< 3). Native LiP under mild conditions (half-life (t1/2) of 8.2 days at pH 6) exhibits a marked decline in thermostability under acidic conditions (t1/2 of only 14 min at pH 2.5). Thus, improving the thermostability of LiP in acidic environments is required for effective lignin depolymerization in practical applications. Here, we show the improved thermostability of a synthetic LiPH8 variant (S49C/A67C/H239E, PDB: 6ISS) capable of strengthening the helix-loop interactions under acidic conditions. This variant retained excellent thermostability at pH 2.5 with a 10-fold increase in t1/2 (2.52 h at 25 °C) compared with that of the native enzyme. X-ray crystallography analysis showed that the recombinant LiPH8 variant is the only unique lignin peroxidase containing five disulfide bridges, and the helix-loop interactions of the synthetic disulfide bridge and ionic salt bridge in its structure are responsible for stabilizing the Ca2+-binding region and heme environment, resulting in an increase in overall structural resistance against acidic conditions. Our work will allow the design of biocatalysts for ligninolytic enzyme engineering and for efficient biocatalytic degradation of plant biomass in lignocellulose biorefineries.


Assuntos
Dissulfetos , Peroxidases , Biocatálise , Biomassa , Lignina/metabolismo , Peroxidases/genética , Peroxidases/metabolismo
9.
J Microbiol Biotechnol ; 31(5): 705-709, 2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-33820889

RESUMO

Porphyromonas gingivalis (P. gingivalis) is a major bacterial pathogen that causes periodontitis, a chronic inflammatory disease of tissues around the teeth. Periodontitis is known to be related to other diseases, such as oral cancer, Alzheimer's disease, and rheumatism. Thus, a precise and sensitive test to detect P. gingivalis is necessary for the early diagnosis of periodontitis. The objective of this study was to optimize a rapid visual detection system for P. gingivalis. First, we performed a visual membrane immunoassay using 3,3',5,5'-tetramethylbenzidine (TMB; blue) and coating and detection antibodies that could bind to the host laboratory strain, ATCC 33277. Antibodies against the P. gingivalis surface adhesion molecules RgpB (arginine proteinase) and Kgp (lysine proteinase) were determined to be the most specific coating and detection antibodies, respectively. Using these two selected antibodies, the streptavidin-horseradish peroxidase (HRP) reaction was performed using a nitrocellulose membrane and visualized with a detection range of 103-105 bacterial cells/ml following incubation for 15 min. These selected conditions were applied to test other oral bacteria, and the results showed that P. gingivalis could be detected without crossreactivity to other bacteria, including Streptococcus mutans and Escherichia fergusonii. Furthermore, three clinical strains of P. gingivalis, KCOM 2880, KCOM 2803, and KCOM 3190, were also recognized using this optimized enzyme immunoassay (EIA) system. To conclude, we established optimized conditions for P. gingivalis detection with specificity, accuracy, and sensitivity. These results could be utilized to manufacture economical and rapid detection kits for P. gingivalis.


Assuntos
Técnicas Bacteriológicas/métodos , Porphyromonas gingivalis/isolamento & purificação , Colorimetria , Cisteína Endopeptidases Gingipaínas/imunologia , Humanos , Técnicas Imunoenzimáticas , Limite de Detecção , Periodontite/diagnóstico , Periodontite/microbiologia , Porphyromonas gingivalis/imunologia
10.
Restor Dent Endod ; 44(1): e7, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30834229

RESUMO

Apical periodontitis is a biofilm-mediated infection. The biofilm protects bacteria from host defenses and increase their resistance to intracanal disinfecting protocols. Understanding the virulence of these endodontic microbiota within biofilm is essential for the development of novel therapeutic procedures for intracanal disinfection. Both the disruption of biofilms and the killing of their bacteria are necessary to effectively treat apical periodontitis. Accordingly, a review of endodontic biofilm types, antimicrobial resistance mechanisms, and current and future therapeutic procedures for endodontic biofilm is provided.

11.
J Endod ; 43(11): 1857-1861, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28951032

RESUMO

INTRODUCTION: The aim of this study was to assess the antifungal efficacy of a synthetic human beta-defensin-3-C15 peptide (HBD3-C15) in Candida albicans-infected human root dentin. METHODS: Standardized root dentin blocks were prepared (6-mm thick, 0.7-mm-wide canal) from single-rooted human permanent premolars and infected with C. albicans for 3 weeks. They were randomly divided into 4 groups (n = 8/group), and their canals were filled with calcium hydroxide (CH), HBD3-C15 peptide, or chlorhexidine digluconate (CHX, 2%) as disinfectants or saline as control. After 1 week of disinfection, dentinal debris were harvested at depths of 200 and 400 µm from the canal lumen, and incubated in Yeast broth for 72 hours at 37°C. Then, colony-forming units (CFU) were measured to assess the antifungal efficacy of each medicament and analyzed statistically. RESULTS: All medicaments showed significantly lower CFU than saline (P < .05), and their antifungal efficacies were similar at both 200- and 400-µm tubular depths (P > .05). HBD3-C15 had similar antifungal efficacy to that of CHX at both depths (P > .05), and both medicaments had significantly lower CFU than CH at both depths (P < .05). CONCLUSIONS: In this ex vivo model of C. albicans-infected human root dentin, the antifungal efficacy of synthetic HBD3-C15 was comparable with CHX.


Assuntos
Antifúngicos/uso terapêutico , Candidíase Bucal/tratamento farmacológico , Dentina/microbiologia , Raiz Dentária/microbiologia , beta-Defensinas/uso terapêutico , Humanos
12.
Am J Pathol ; 186(5): 1140-50, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27105735

RESUMO

Despite similar components, the heterogeneity of skin characteristics across the human body is enormous. It is classically believed that site-specific fibroblasts in the dermis control postnatal skin identity by modulating the behavior of the surface-overlying keratinocytes in the epidermis. To begin testing this hypothesis, we characterized the gene expression differences between volar (ventral; palmoplantar) and nonvolar (dorsal) human skin. We show that KERATIN 9 (KRT9) is the most uniquely enriched transcript in volar skin, consistent with its etiology in genetic diseases of the palms and soles. In addition, ectopic KRT9 expression is selectively activated by volar fibroblasts. However, KRT9 expression occurs in the absence of all fibroblasts, although not to the maximal levels induced by fibroblasts. Through gain-of-function and loss-of-function experiments, we demonstrate that the mechanism is through overlapping paracrine or autocrine canonical WNT-ß-catenin signaling in each respective context. Finally, as an in vivo example of ectopic expression of KRT9 independent of volar fibroblasts, we demonstrate that in the human skin disease lichen simplex chronicus, WNT5a and KRT9 are robustly activated outside of volar sites. These results highlight the complexities of site-specific gene expression and its disruption in skin disease.


Assuntos
Dermatoses do Pé/metabolismo , Dermatoses da Mão/metabolismo , Queratina-9/metabolismo , Pele/metabolismo , Via de Sinalização Wnt/fisiologia , Animais , Diferenciação Celular/fisiologia , Feminino , Fibroblastos/fisiologia , Imunofluorescência , Expressão Gênica/fisiologia , Técnicas de Silenciamento de Genes , Humanos , Queratina-5/metabolismo , Queratina-9/genética , Queratinócitos/fisiologia , Masculino , Camundongos Endogâmicos C57BL , Neurodermatite/metabolismo , Psoríase/metabolismo , RNA Mensageiro/metabolismo , Via de Sinalização Wnt/genética , Proteína Wnt-5a/metabolismo , beta Catenina/fisiologia
13.
Acta Biomater ; 10(11): 4606-4617, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25110285

RESUMO

Respiratory syncytial virus (RSV) is one of the most common causes of viral deaths in infants worldwide, yet no effective vaccines are available. Here, we report an osmotically active polysaccharide-based polysorbitol transporter (PST) prepared from sorbitol diacrylate and low-molecular-weight polyethylenimine (PEI) showing a potent, yet safe, adjuvant activity and acting as an effective delivery tool for RSV glycoprotein (RGp) antigen. PST showed no toxicity in vitro or in vivo, unlike PEI and the well-known experimental mucosal adjuvant cholera toxin (CT). PST formed nano-sized complexes with RGp by simple mixing, without affecting antigenic stability. The complexes exhibited negative surface charges that made them highly efficient in the selective activation of phagocytic cells and enhancement of phagocytic uptake. This resulted in an improved cytokine production and in the significant augmentation of RGp-specific antibody production, which persisted for over 200 days. Interestingly, PST/RGp enhanced phagocytic uptake owing to the osmotic property of PST and its negative zeta potential, suggesting that PST could selectively stimulate phagocytic cells, thereby facilitating a long-lived antigen-specific immune response, which was presumably further enhanced by the polysaccharide properties of PST.


Assuntos
Glicoproteínas/imunologia , Imunidade/efeitos dos fármacos , Nanopartículas/química , Poliésteres/química , Polietilenoimina/análogos & derivados , Vírus Sinciciais Respiratórios/imunologia , Proteínas Virais/imunologia , Animais , Linhagem Celular , Forma Celular/efeitos dos fármacos , Feminino , Fluoresceína-5-Isotiocianato , Humanos , Macrófagos/efeitos dos fármacos , Macrófagos/ultraestrutura , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Nanopartículas/ultraestrutura , Concentração Osmolar , Fagocitose/efeitos dos fármacos , Poliésteres/síntese química , Poliésteres/toxicidade , Polietilenoimina/síntese química , Polietilenoimina/química , Polietilenoimina/toxicidade , Vírus Sinciciais Respiratórios/efeitos dos fármacos
14.
Int J Oral Sci ; 6(4): 227-32, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25012869

RESUMO

The time domain entombment of bacteria by intratubular mineralization following orthograde canal obturation with mineral trioxide aggregate (MTA) was studied by scanning electron microscopy (SEM). Single-rooted human premolars (n=60) were instrumented to an apical size #50/0.06 using ProFile and treated as follows: Group 1 (n=10) was filled with phosphate buffered saline (PBS); Group 2 (n=10) was incubated with Enterococcus faecalis for 3 weeks, and then filled with PBS; Group 3 (n=20) was obturated orthograde with a paste of OrthoMTA (BioMTA, Seoul, Korea) and PBS; and Group 4 (n=20) was incubated with E. faecalis for 3 weeks and then obturated with OrthoMTA-PBS paste. Following their treatments, the coronal openings were sealed with PBS-soaked cotton and intermediate restorative material (IRM), and the roots were then stored in PBS for 1, 2, 4, 8 or 16 weeks. After each incubation period, the roots were split and their dentin/MTA interfaces examined in both longitudinal and horizontal directions by SEM. There appeared to be an increase in intratubular mineralization over time in the OrthoMTA-filled roots (Groups 3 and 4). Furthermore, there was a gradual entombment of bacteria within the dentinal tubules in the E. faecalis inoculated MTA-filled roots (Group 4). Therefore, the orthograde obturation of root canals with OrthoMTA mixed with PBS may create a favorable environment for bacterial entombment by intratubular mineralization.


Assuntos
Compostos de Alumínio/uso terapêutico , Compostos de Cálcio/uso terapêutico , Cavidade Pulpar/microbiologia , Dentina/microbiologia , Enterococcus faecalis/ultraestrutura , Óxidos/uso terapêutico , Materiais Restauradores do Canal Radicular/uso terapêutico , Silicatos/uso terapêutico , Calcificação Fisiológica/fisiologia , Cristalização , Combinação de Medicamentos , Humanos , Metilmetacrilatos/uso terapêutico , Microscopia Eletrônica de Varredura , Obturação do Canal Radicular/métodos , Preparo de Canal Radicular/instrumentação , Fatores de Tempo , Cimento de Óxido de Zinco e Eugenol/uso terapêutico
15.
Infect Immun ; 82(5): 1914-20, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24566622

RESUMO

Toll-like receptors (TLRs) orchestrate a repertoire of immune responses in macrophages against various pathogens. Fusobacterium nucleatum and Aggregatibacter actinomycetemcomitans are two important periodontal pathogens. In the present study, we investigated TLR signaling regulating cytokine production of macrophages in response to F. nucleatum and A. actinomycetemcomitans. TLR2 and TLR4 are redundant in the production of cytokines (interleukin-6 [IL-6] and tumor necrosis factor alpha [TNF-α]) in F. nucleatum- and A. actinomycetemcomitans-infected macrophages. The production of cytokines by macrophages in response to F. nucleatum and A. actinomycetemcomitans infection was impaired in MyD88-deficient macrophages. Moreover, cytokine concentrations were lower in MyD88-deficient macrophages than in TLR2/TLR4 (TLR2/4) double-deficient cells. An endosomal TLR inhibitor, chloroquine, reduced cytokine production in TLR2/4-deficient macrophages in response to F. nucleatum and A. actinomycetemcomitans, and DNA from F. nucleatum or A. actinomycetemcomitans induced IL-6 production in bone marrow-derived macrophages (BMDMs), which was abolished by chloroquine. Western blot analysis revealed that TLR2/4 and MyD88 were required for optimal activation of NF-κB and mitogen-activated protein kinases (MAPKs) in macrophages in response to F. nucleatum and A. actinomycetemcomitans, with different kinetics. An inhibitor assay showed that NF-κB and all MAPKs (p38, extracellular signal-regulated kinase [ERK], and Jun N-terminal protein kinase [JNK]) mediate F. nucleatum-induced production of cytokines in macrophages, whereas NF-κB and p38, but not ERK and JNK, are involved in A. actinomycetemcomitans-mediated cytokine production. These findings suggest that multiple TLRs may participate in the cytokine production of macrophages against periodontal bacteria.


Assuntos
Aggregatibacter actinomycetemcomitans/fisiologia , Citocinas/metabolismo , Fusobacterium nucleatum/fisiologia , Macrófagos/metabolismo , Receptores Toll-Like/metabolismo , Animais , Citocinas/genética , Infecções por Fusobacterium/imunologia , Infecções por Fusobacterium/metabolismo , Infecções por Fusobacterium/microbiologia , Regulação da Expressão Gênica/fisiologia , Camundongos , Camundongos Knockout , Infecções por Pasteurellaceae/imunologia , Infecções por Pasteurellaceae/metabolismo , Infecções por Pasteurellaceae/microbiologia , Receptores Toll-Like/genética
16.
J Endod ; 37(12): 1673-6, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22099903

RESUMO

INTRODUCTION: Recently, several kinds of mineral trioxide aggregate (MTA)-based products have been introduced in endodontics. Ortho MTA (BioMTA, Seoul, Republic of Korea) is one of those products, which was developed for retrograde filling, perforation repair, orthograde root canal obturation, and direct pulp capping. The inclusion of heavy metals in MTA-based materials is of concern because they come into direct contact with hard and soft tissues. The aim of this study was to investigate and compare the levels of arsenic (As), chromium (Cr), hexavalent chromium (Cr(6+)), and lead (Pb) in Ortho MTA and ProRoot MTA. METHODS: One gram of each MTA was digested using a mixture of hydrochloric and nitric acids and filtered. The As, Cr, and Pb in the resulting filtrates were analyzed by inductively coupled plasma-optical emission spectrometry. The level of Cr(6+) was measured by the methods suggested in the Korean Standard L 5221. The results were statistically analyzed using the Mann-Whitney U test. RESULTS: The concentration of As in ProRoot MTA was 1.16 ppm, but As was not detected in Ortho MTA. Cr(6+) and Pb were not detected in either MTA. Ortho MTA contained significantly less Cr than ProRoot MTA (P < .05). CONCLUSIONS: Ortho MTA and ProRoot MTA meet the ISO specification 9917-1 regarding the safety limits of As and Pb and are safe biomaterials when the purity of As, Cr(6+), and Pb is considered.


Assuntos
Compostos de Alumínio/análise , Compostos de Cálcio/análise , Metais Pesados/análise , Óxidos/análise , Materiais Restauradores do Canal Radicular/análise , Silicatos/análise , Arsênio/análise , Carcinógenos Ambientais/análise , Cromo/análise , Combinação de Medicamentos , Humanos , Ácido Clorídrico/química , Chumbo/análise , Teste de Materiais , Ácido Nítrico/química , Espectrofotometria Atômica
17.
Eur J Pharmacol ; 668(3): 459-66, 2011 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-21827747

RESUMO

B cell-activating factor (BAFF) is a key regulator of B lymphocyte development. Signals from BAFF are transmitted through binding to a specific BAFF receptor (BAFF-R). Here, we established screening method to find a specific inhibitor for the interference of BAFF-BAFF-R interactions. We screened oxazole-4-carbonylguanidine derivatives and selected KR33426, [2-(2,5-dichlorophenyl)-5-methyloxazol-4yl]carbonylguanidine, as a candidate to interfere BAFF-BAFF-R interactions. KR33426 inhibited BAFF-mediated anti-apoptotic effect on splenocytes as judged by hypodiploid cell formation. KR33426 also increased the degradation of procaspase-3 that was inhibited by BAFF protein. In addition, we examined whether KR33426 was effective on the treatment of systemic lupus erythematosus-like symptom in MRL(lpr/lpr) mouse. When 5 or 10mg/kg KR33426 was intraperitoneally administered to MRL(lpr/lpr) mice for 4 weeks, histopathological changes were ameliorated in the narrowed space between renal glomerulus and glomerulus capsule. KR33426 reduced B220(+) B cell population and B cell mitogen, lipopolysaccharide-stimulated lymphocyte proliferation in splenocytes. KR33426 attenuated an increase in CD43(-)IgM(+) immature pro-B and a decrease in CD21(+) IgM(+) T2-B and IgD(+) IgM(-)recirculating-B cells on B cell development. Data show that KR33426 inhibits BAFF-BAFF-R interactions and it is effective on the treatment of systemic lupus erythematosus-like symptom in MRL(lpr/lpr) mice. Thus, it suggests that KR33426 is a novel candidate to develop anti-autoimmune therapeutics by the interference of BAFF-BAFF-R interactions, specifically.


Assuntos
Guanidinas/farmacologia , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Oxazóis/farmacologia , Animais , Apoptose/efeitos dos fármacos , Fator Ativador de Células B/metabolismo , Receptor do Fator Ativador de Células B/metabolismo , Linfócitos B/efeitos dos fármacos , Linfócitos B/patologia , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Feminino , Guanidinas/uso terapêutico , Lúpus Eritematoso Sistêmico/imunologia , Lúpus Eritematoso Sistêmico/metabolismo , Camundongos , Baço/imunologia
18.
Acta Pharmacol Sin ; 28(6): 901-7, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17506950

RESUMO

AIM: To investigate the immunoregulatory functions of water extracts of Hericium erinaceum (WEHE) focusing on natural killer (NK) cell-based anticancer activities. METHODS: Mouse splenocytes or purely isolated NK cells were stimulated with 1-100 mg/L WEHE for 24 h followed by co-culture with (51)Cr-labeled Yac-1 cells for 4 h, then NK cell-derived cytolytic activity was measured using a radio-release assay. Neutralizing antibodies against mouse interleukin-12 (IL-12) were added into the WEHE-stimulated splenocytes, thereafter, cytotoxicity was measured to examine the involvement of IL-12. RT-PCR and ELISA analyses were performed to confirm the induction of transcription and the translation of IL-12 and interferon-gamma (IFN-gamma) in the WEHE-treated splenocytes. RESULTS: WEHE enhanced the cytolytic activity of total splenocytes towards Yac-1 cells in a dose-dependent manner. However, this activation was not observed when the NK cells isolated from the splenocytes were treated with WEHE. Furthermore, the treatment with antibodies against IL-12 abolished the effect of WEHE on splenocyte-derived cytolytic activity. RT-PCR and ELISA analyses showed the induction of IL-12 and IFN-gamma in the WEHE-treated splenocytes. CONCLUSION: WEHE indirectly activates the cytolytic ability of NK cells via the induction of IL-12 in total splenocytes, and possibly via other immuno-mediators or cellular components.


Assuntos
Agaricales/química , Fatores Imunológicos/farmacologia , Interleucina-12/imunologia , Células Matadoras Naturais , Ativação Linfocitária/efeitos dos fármacos , Baço/citologia , Animais , Linhagem Celular , Humanos , Fatores Imunológicos/imunologia , Interferon gama/imunologia , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Biossíntese de Proteínas , Transcrição Gênica
19.
World J Gastroenterol ; 12(46): 7497-502, 2006 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-17167840

RESUMO

AIM: To evaluate the pharmaceutical safety of a Chinese herbal formula, chunggan extract (CGX), traditionally prescribed as a hepatotherapeutic drug via systemic acute and subacute toxicological study. METHODS: Twenty male dogs and 20 female dogs were fed doses 50 times and 4 times greater than the clinically-recommended drug dosages in an acute and a subacute toxicological study, respectively. Adverse effects were examined by comparing the differences between normal and drug-administered groups using clinical signs, necropsies, histopathologic findings, haematology, urinalysis, and biochemical analysis. RESULTS: In the acute study no change in the body weight, diarrhoea, apetite, mortality rate and histopathology of major organs was observed in male or female dogs with a single administration of CGX at 5 g/kg. No drug-induced abnormalities at analysis of histopathology, haematology, urinalysis, and biochemistry were found with any dose of this drug. CONCLUSION: CGX is supposed to be very safe when used in a clinical application with a wide therapeutic index.


Assuntos
Medicamentos de Ervas Chinesas/toxicidade , Animais , Peso Corporal/efeitos dos fármacos , Cães , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/uso terapêutico , Ingestão de Alimentos/efeitos dos fármacos , Feminino , Humanos , Rim/efeitos dos fármacos , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Hepatopatias/tratamento farmacológico , Masculino , Fitoterapia/efeitos adversos , Segurança
20.
World J Gastroenterol ; 12(38): 6142-8, 2006 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-17036385

RESUMO

AIM: To evaluate the therapeutic effect of Chunggan extract (CGX), a modified traditional Chinese hepatotherapeutic herbal, on the dimethylnitrosamine (DMN)-induced chronic liver injury model in rats. METHODS: Liver injuries were induced in Wistar rats by injection of DMN (ip, 10 mg/mL per kg) for 3 consecutive days per week for 4 wk. The rats were administered with CGX (po, 100 or 200 mg/kg per day) or distilled water as a control daily for 4 wk starting from the 15(th) d of the DMN treatment. Biochemical parameters (serum albumin, bilirubin, ALP, AST and ALT), lipid peroxides, hydroxyproline, as well as histological changes in liver tissues were analyzed. In addition, gene expression of TNF-alpha, TGF-beta, TIMP-1, TIMP-2, PDGF-beta, and MMP-2, all of which are known to be associated with liver fibrosis, were analyzed using real-time PCR. RESULTS: CGX administration restored the spleen weight to normal after having been increased by DMN treatment. Biochemical analysis of the serum demonstrated that CGX significantly decreased the serum level of ALP (P < 0.05), ALT (P < 0.01), and AST (P < 0.01) that had been elevated by DMN treatment. CGX administration moderately lowered lipid peroxide production and markedly lowered hydroxyproline generation caused by DMN treatment in accordance with histopathological examination. DMN treatment induced a highly up-regulated expression of TNF-alpha, TGF-beta, TIMP-1, TIMP-2, PDGF-beta, and MMP-2. Of these, the gene expression encoding PDGF-beta and MMP-2 was still further enhanced 2 wk after secession of the 4-wk DMN treatment, and was remarkably ameliorated by CGX administration. CONCLUSION: CGX exhibits hepatotherapeutic proper-ties against chronic hepatocellular destruction and consequential liver fibrosis.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Cirrose Hepática/prevenção & controle , Fígado/efeitos dos fármacos , Animais , Dimetilnitrosamina , Medicamentos de Ervas Chinesas/uso terapêutico , Expressão Gênica , Hidroxiprolina/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/patologia , Hepatopatias/sangue , Hepatopatias/tratamento farmacológico , Hepatopatias/patologia , Masculino , Tamanho do Órgão , Ratos , Ratos Wistar , Baço/patologia
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