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1.
Fish Physiol Biochem ; 47(5): 1415-1427, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34292455

ABSTRACT

Almost all prey live in habitats with predators with different hunting modes; however, most studies on predation have investigated the effects of only one predator at a time. In this study, we aimed to investigate whether qingbo (Spinibarbus sinensis), a common cyprinid fish, responds differently to active hunting and ambush predators and how qingbo responds when both types of predators coexist. Juvenile qingbo were subjected to catfish (Clarias fuscus, active hunter) exposure, snakehead fish (Channa argus, ambush hunter) exposure, or mixed predator exposure (catfish and snakehead coexistence) for a duration of 60 days. Then, their growth, behaviors, swimming performance, and metabolism were measured. Qingbo subjected to active hunting predator exposure exhibited decreased activity and predator inspection and improved fast-start escape performance compared to those in the control group. However, none of the parameters of the fish subjected to ambush predator exposure changed significantly. Fish subjected to mixed predator exposure exhibited improved fast-start escape performance but increased maintenance energy expenditure, whereas no changes were observed in any of the behavioral variables. Qingbo showed a stronger anti-predator response to active hunting predators than to ambush predators, suggesting that the fish exhibit a stronger anti-predator response to a current direct threat than to a potential threat (a predator exists nearby but seldom presents in attack behavior). Additionally, the response of prey fish to multiple predators was quite complex, and the coexistence and interaction of multiple predator species with different hunting modes may lead to serious stress responses and confound the prey's behavioral responses to each predator.


Subject(s)
Cyprinidae , Hunting , Animals , Ecosystem , Locomotion , Predatory Behavior
2.
Chin J Nat Med ; 18(11): 850-854, 2020 Nov.
Article in English | MEDLINE | ID: mdl-33308607

ABSTRACT

Three new mycophenolic acid derivatives, penicacids E-G (1-3), together with three known analogues, mycophenolic acid (4), 4'-hydroxy-mycophenolic acid (5) and mycophenolic methyl ester (6), were isolated from a marine-derived fungus Penicillium parvum HDN17-478 from a South China Sea marine sediment sample. The structures of compounds 1-3 were elucidated by HRMS, NMR, and Mosher's method. Among them, compounds 1 and 2 were the first examples of mycophenolic acid analogs with a double bond at C-3'/C-4' position. The cytotoxicity of 1-6 was evaluated against the HCT-116, BEL-7402, MGC-803, SH-SY5Y, HO-8910 and HL-60 cell lines, and compounds 4 and 6 showed potent cytotoxicity with IC50 values ranging from 1.69 to 12.98 µmol·L-1.


Subject(s)
Mycophenolic Acid/analogs & derivatives , Penicillium/chemistry , Aquatic Organisms/chemistry , Cell Line, Tumor , China , Drug Screening Assays, Antitumor , Geologic Sediments/microbiology , Humans , Molecular Structure , Mycophenolic Acid/isolation & purification , Mycophenolic Acid/pharmacology , Pacific Ocean
3.
J Asian Nat Prod Res ; 22(11): 1031-1036, 2020 Nov.
Article in English | MEDLINE | ID: mdl-31755305

ABSTRACT

One new ß,γ-butenoate derivative phenylbutenote (1), and one new α-pyrone nocapyrone T (2) were isolated from the deep-sea derived actinomycete Nocardiopsis sp. HDN 17-237. Their structures were elucidated by extensive HRMS, IR and NMR analyses. Among them, compound 1 is the first microbial natural products bearing a rare ß,γ-butenoate moiety, and compound 2 is the first α-pyrone isolated from strain of Mariana Trench. Compounds 1 and 2 were tested for antioxidant and antibacterial activities, while none of them showed significant activity.


Subject(s)
Actinobacteria , Nocardia , Magnetic Resonance Spectroscopy , Molecular Structure , Pyrones/pharmacology
4.
Photochem Photobiol ; 95(3): 812-822, 2019 05.
Article in English | MEDLINE | ID: mdl-30338861

ABSTRACT

Hypocrellin A (HA), a promising photosensitizer for anticancer photodynamic therapy (PDT), is a fungal perylenequinone pigment from the fruiting body of Shiraia bambusicola, a traditional Chinese medicine for treating skin diseases. The mycelial cultures are becoming a biotechnological alternative for HA production. In this study, light of different wavelengths was investigated to develop an effective eliciting strategy for HA production in the cultures. Under red LED light (627 nm) at 200 lux, the maximum HA production (175.53 mg L-1 ) in mycelium cultures was reached after 8 days, about 3.82-fold of the dark control. Red light not only promoted HA biosynthesis in mycelia (intracellular HA), but also stimulated HA secretion into the medium (extracellular HA). We found 14 of 310 transcripts differentially expressed under red light treatment were possible candidate genes for HA biosynthetic pathway. Gene ontology (GO) analysis revealed that red light treatment could change the gene expressions responsible for HA biosynthesis and the transmembrane activity, suggesting both intracellular HA and its secretion could contribute to the enhancement of total HA production in the cultures. The results provided new insights of red light elicitation and effective strategy for HA production in mycelium cultures.


Subject(s)
Ascomycota/radiation effects , Light , Perylene/analogs & derivatives , Photosensitizing Agents/metabolism , Quinones/metabolism , Ascomycota/genetics , Ascomycota/metabolism , Biosynthetic Pathways , Cell Membrane Permeability/radiation effects , Genes, Fungal , Molecular Sequence Annotation , Mycelium/growth & development , Perylene/metabolism , Phenol , Transcriptome
5.
Entropy (Basel) ; 21(8)2019 Aug 16.
Article in English | MEDLINE | ID: mdl-33267515

ABSTRACT

Chromatin immunoprecipitation combined with next-generation sequencing (ChIP-Seq) technology has enabled the identification of transcription factor binding sites (TFBSs) on a genome-wide scale. To effectively and efficiently discover TFBSs in the thousand or more DNA sequences generated by a ChIP-Seq data set, we propose a new algorithm named AP-ChIP. First, we set two thresholds based on probabilistic analysis to construct and further filter the cluster subsets. Then, we use Affinity Propagation (AP) clustering on the candidate cluster subsets to find the potential motifs. Experimental results on simulated data show that the AP-ChIP algorithm is able to make an almost accurate prediction of TFBSs in a reasonable time. Also, the validity of the AP-ChIP algorithm is tested on a real ChIP-Seq data set.

6.
Nat Prod Res ; 33(20): 2977-2981, 2019 Oct.
Article in English | MEDLINE | ID: mdl-30417660

ABSTRACT

Two new polyketides, purpurofuranone (1) and purpuropyranone (2), were isolated along with the known polyketides, cillifuranone (3) and taiwapyrone (4), from a mutant BD-3n-1 derived from the diethyl sulfate (DES) mutagenesis of a marine-derived Penicillium purpurogenum G59. The structures of 1 and 2 were elucidated by spectroscopic methods especially on the basis of X-ray diffraction and calculated optical rotations data. The plausible biosynthesis of 1 - 4 was also proposed and discussed. In preliminary MTT assay, 1 - 4 showed no notable inhibitory effects on the tested four human cancer cell lines.


Subject(s)
Mutagenesis , Penicillium/genetics , Polyketides/isolation & purification , Antineoplastic Agents/isolation & purification , Antineoplastic Agents/pharmacology , Cell Line, Tumor , Drug Screening Assays, Antitumor , Humans , Molecular Structure , Mutagenesis/drug effects , Penicillium/chemistry , Polyketides/chemistry , Spectrum Analysis , Sulfuric Acid Esters/toxicity
7.
Inorg Chem ; 57(13): 7975-7981, 2018 Jul 02.
Article in English | MEDLINE | ID: mdl-29911863

ABSTRACT

Metal-organic frameworks (MOFs) have gained tremendous attention in the fields of environmental restoration and sustainable energy for their potential use as photocatalyst. Herein, a new two-dimensional (2D) Cu(I)-based MOF material showing a narrow forbidden-band of 2.13 eV was successfully constructed using a visible-light-harvesting anthracene-based bipyridine ligand. The as-prepared MOF demonstrates high chemical stability and could be stable in the pH range 2-13, which is favorable for its potential application in photocatalysis. Photocatalytic experiments demonstrate that this Cu(I)-MOF exhibits high reactivity for reduction of Cr(VI) in water, with 95% Cr(VI) converting to Cr(III) in 10 min by using MeOH as scavenger under visible-light illumination. Furthermore, this MOF could behave as a highly active photocatalyst for H2 evolution without additional photosensitizers and cocatalyst. Remarkably, the as-prepared MOF shows enhanced photocatalytic Cr(VI) reduction and H2 evolution performances compared with the pristine light-harvesting ligand under the same conditions. In connection to these, the photocatalytic reaction mechanism has also been probed.

8.
J Photochem Photobiol B ; 182: 100-107, 2018 May.
Article in English | MEDLINE | ID: mdl-29656218

ABSTRACT

Hypocrellin A (HA) is a major bioactive perylenequinone from the fruiting body of Shiraia bambusicola used for the treatment of skin diseases and developed as a photodynamic therapy (PDT) agent against cancers and viruses. The mycelial culture of S. bambusicola under dark is a biotechnological alternative for HA production but with low yield. In this study, light and dark conditions were investigated to develop effective elicitation on HA production in the cultures. Our results showed the constant light at 200 lx stimulated HA production without any growth retardation of mycelia. A light/dark shift (24: 24 h) not only increased HA content in mycelia by 65%, but stimulated HA release into the medium with the highest total HA production 181.67 mg/L on day 8, about 73% increase over the dark control. Moreover, light/dark shifting induced the formation of smaller and more compact fungal pellets, suggesting a new effective strategy for large-scale production of HA in mycelium cultures. The light/dark shift up-regulated the expression levels of two reactive oxygen species (ROS) related genes including superoxide-generating NADPH oxidase (Nox) and cytochrome c peroxidase (CCP), and induced the generation of ROS. With the treatment of vitamin C, we found that ROS was involved in the up-regulated expression of key biosynthetical genes for hypocrellins and improved HA production. These results provide a basis for understanding the influence of light/dark shift on fungal metabolism and the application of a novel strategy for enhancing HA production in submerged Shiraia cultures.


Subject(s)
Ascomycota/chemistry , Gene Expression Regulation, Fungal/radiation effects , Industrial Microbiology/methods , Light , Perylene/analogs & derivatives , Quinones/metabolism , Reactive Oxygen Species/metabolism , Ascomycota/metabolism , Ascomycota/radiation effects , Mycelium/growth & development , Mycelium/metabolism , Mycelium/radiation effects , Perylene/chemistry , Perylene/metabolism , Phenol , Photoperiod , Quinones/chemistry , Real-Time Polymerase Chain Reaction
9.
Inorg Chem ; 57(5): 2883-2889, 2018 Mar 05.
Article in English | MEDLINE | ID: mdl-29470067

ABSTRACT

As a modulatable class of porous crystalline materials, metal-organic frameworks (MOFs) have gained intensive research attention in the domain of gas storage and separation. In this study, we report on the synthesis and gas adsorption properties of two robust MOFs with the general formula [Co3(µ3-OH)(cpt)3Co3(µ3-OH)(L)3(H2O)9](NO3)4(guests) n [L = 3-amino-1,2,4-triazole (1) and 3,5-diamino-1,2,4-triazole (2); Hcpt = 4-(4-carboxyphenyl)-1,2,4-triazole], which show the same pacs topology. Both MOFs are isostructural to each other and show MIL-88-type frameworks whose pore spaces are partitioned by different functionlized trinuclear 1,2,4-triazolate-based clusters. The similar framework components with different amounts of functional groups make them an ideal platform to permit a systematic gas sorption/separation study to evaluate the effects of distinctive parameters on the C2H2 uptake and separation performance. Because of the presence of additional amido groups, the MOF 2 equipped with a datz-based cluster (Hdatz = 3,5-diamino-1,2,4-triazole) shows a much improved C2H2 uptake capacity and separation performance over that of the MOF 1 equipped with atz-based clusters (Hatz = 3-amino-1,2,4-triazole), although the surface area of the MOF 1 is almost twice than that of the MOF 2. Moreover, the high density of open metal sites, abundant free amido groups, and charged framework give the MOF 2 an excellent C2H2 separation performance, with ideal adsorbed solution theory selectivity values reaching up to 11.5 and 13 for C2H2/C2H4 (1:99) and C2H2/CO2 (50:50) at 298 K and 1 bar, showing potential for use in natural gas purification.

10.
Angew Chem Int Ed Engl ; 56(46): 14637-14641, 2017 11 13.
Article in English | MEDLINE | ID: mdl-28963739

ABSTRACT

As the first example of a photocatalytic system for splitting water without additional cocatalysts and photosensitizers, the comparatively cost-effective Cu2 I2 -based MOF, Cu-I-bpy (bpy=4,4'-bipyridine) exhibited highly efficient photocatalytic hydrogen production (7.09 mmol g-1 h-1 ). Density functional theory (DFT) calculations established the electronic structures of Cu-I-bpy with a narrow band gap of 2.05 eV, indicating its semiconductive behavior, which is consistent with the experimental value of 2.00 eV. The proposed mechanism demonstrates that Cu2 I2 clusters of Cu-I-bpy serve as photoelectron generators to accelerate the copper(I) hydride interaction, providing redox reaction sites for hydrogen evolution. The highly stable cocatalyst-free and self-sensitized Cu-I-bpy provides new insights into the future design of cost-effective d10 -based MOFs for highly efficient and long-term solar fuels production.

11.
Ultrason Sonochem ; 38: 214-224, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28633821

ABSTRACT

Hypocrellin A (HA), a naturally occurring fungal perylenequinone, is widely used in clinic to treat skin diseases and developed as a photodynamic therapy (PDT) agent against cancers. In this study, a low intensity ultrasound (US, 0.28W/cm2 at 40kHz) was conducted thrice of repeated US exposure (5-min) with an interval of 12h to stimulate HA production of Shiraia bambusicola after 72h of the initial submerged cultures. US not only increased the content of HA by 177.2% in mycelia, but stimulated the release of HA into the medium with the highest total production of HA (247.67mg/L) on day 8. US could result in the decreased pellet diameter, the enhanced membrane permeability, the alternation of membrane compounds and reactive oxygen species (ROS) generation. Furthermore, the ultrasonic treatment up-regulated the expression of some HA biosynthetic genes including polyketide synthase gene (PKS), O-methyltransferase gene (Omef), O-methyltransferase/FAD-dependent monooxygenase (Mono) and FAD/FMN-dependent oxidoreductase gene (FAD), and activated major facilitator superfamily transporter gene (MFS) for HA exudation. The enhancement of HA production was mainly due to both the stimulated cellular biosynthesis and the enhanced fungal exudation of HA. These results provide a basis for understanding the US elicitation and a valuable strategy for enhancing HA production in submerged Shiraia cultures.


Subject(s)
Ascomycota/growth & development , Ascomycota/metabolism , Culture Techniques/methods , Perylene/analogs & derivatives , Quinones/metabolism , Ultrasonic Waves , Ascomycota/cytology , Cell Membrane/metabolism , Immersion , Perylene/metabolism , Phenol
12.
Biosens Bioelectron ; 91: 804-810, 2017 May 15.
Article in English | MEDLINE | ID: mdl-28152486

ABSTRACT

Two unique immunosensors made of aluminum-based metal-organic frameworks (MOFs), namely, 515- and 516-MOFs, with 4,4',4''-nitrilotribenzoic acid (H3NTB) were successfully obtained to efficiently assess food safety. The as-prepared 515- and 516-MOFs exhibited superior thermal and physicochemical stability, high electrochemical activity, and good biocompatibility. Among these immunosensors, 516-MOF showed a preferable biosensing ability toward analytes determined by electrochemical techniques. The developed 516-MOF-based electrochemical biosensor not only demonstrated high sensitivity with low detection limits of 0.70 and 0.40pgmL-1 toward vomitoxin and salbutamol, respectively, but also showed good selectivity in the presence of other interferences. Therefore, with the advantages of high sensitivity, good selectivity, and simple operation, this new strategy is believed to exhibit great potential for simple and convenient detection of poisonous and harmful residues in food.


Subject(s)
Aluminum/chemistry , Electrochemical Techniques/methods , Food Analysis/methods , Food Contamination/analysis , Organometallic Compounds/chemistry , Albuterol/analysis , Animals , Antibodies, Immobilized/chemistry , Biosensing Techniques/methods , Bronchodilator Agents/analysis , Limit of Detection , Models, Molecular , Red Meat/analysis , Swine , Trichothecenes/analysis , Wine/analysis
13.
Cancer Sci ; 106(1): 43-50, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25421527

ABSTRACT

This study aimed to induce malignant transformation of endometriosis in Sprague-Dawley rats by hyperestrogenemia and type II diabetes and evaluate its similarity with human disease in biological features. Rats with surgically induced endometriosis were randomized into two groups: those treated with estradiol (5 mg/kg three times/week after surgery), streptozotocin (25 mg/kg, 1 month after surgery), and high carbohydrate-and-fat feed (Es group); and those treated with placebo saline and standard feed (control group). All rats were randomly killed 2, 4, or 8 months after surgery. The endometriosis lesions and the corresponding eutopic endometria were subjected to morphological evaluation, TUNEL, and immunohistochemical analysis for the expressions of proliferating cell nuclear antigen, phosphatase and tensin homolog, phosphorylated protein kinase B, and phosphorylated mammalian target of rapamycin proteins. In the Es group, three cases (6.0%) of endometriosis showed atypical hyperplasia accompanied by simple hyperplastic eutopic endometria, and two cases (4.0%) of endometriosis showed endometrioid carcinoma accompanied by atypical hyperplastic eutopic endometria. In the Es group, the activity of organelles and the expressions of proliferating cell nuclear antigen, phosphorylated protein kinase B, and phosphorylated mammalian target of rapamycin increased, and the level of phosphatase and tensin homolog and TUNEL positivity decreased progressively in the order of endometriosis, atypical endometriosis, and malignant endometriosis. The same tendency was found in the corresponding eutopic endometria. The induced malignant endometriosis showed similarities with human disease in the pathological process and histomorphological and molecular biological features. The method is feasible. The malignant transformations of endometriosis and eutopic endometria may have correlations and similarities, but the former may suffer a higher risk of canceration.


Subject(s)
Adenocarcinoma/etiology , Diabetes Mellitus, Experimental/complications , Endometrial Neoplasms/etiology , Endometriosis/pathology , Estrogens/blood , Animals , Apoptosis , Cell Proliferation , Cell Transformation, Neoplastic , Endometrium/metabolism , Endometrium/pathology , Estrogens/physiology , Female , PTEN Phosphohydrolase/metabolism , Rats, Sprague-Dawley
14.
J Endod ; 41(1): 1-10, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25306305

ABSTRACT

INTRODUCTION: Clinicians are regularly confronted with difficult choices. Should a tooth that has not healed through nonsurgical root canal treatment be treated through endodontic microsurgery or be replaced using a single implant? Acquiring complete, unbiased information to help clinicians and their patients make these choices requires a systematic review of the literature on treatment outcomes. The purpose of this systematic review was to compare the outcomes of tooth retention through endodontic microsurgery to tooth replacement using an implant supported single crown. METHODS: Searches performed in PubMed, Cochrane Library, Web of Science, and EMBASE databases were enriched by citation mining. Inclusion criteria were defined. Sentinel articles were identified and included in the final selection of studies. Weighted survival and success rates for single implants and endodontic microsurgery were calculated. RESULTS: The quality of the articles reporting on single implants and endodontic microsurgery was moderate. Data for single implants were much more plentiful than for endodontic microsurgery, but the endodontic microsurgery studies had a slightly higher quality rating. Single implants and endodontic microsurgery were not directly compared in the literature. Outcomes criteria were often unclear. At 4-6 years, single implants had higher survival rates than teeth treated with endodontic microsurgery. Qualitatively different success criteria precluded valid comparison of success rates. CONCLUSIONS: Survival rates for single implants and endodontic microsurgery were both high (higher for single implants). Appraisal was limited by a lack of direct treatment comparisons. Long-term studies with a broad range of carefully defined outcomes criteria are needed.


Subject(s)
Dental Implants, Single-Tooth , Microsurgery/methods , Root Canal Therapy/methods , Crowns , Dental Prosthesis, Implant-Supported , Humans , Tooth Extraction , Treatment Outcome
15.
J Oral Implantol ; 39(2): 206-9, 2013 Apr.
Article in English | MEDLINE | ID: mdl-21767210

ABSTRACT

Oral actinomycosis is not a common disease, but it can cause massive destruction. This article reports a case of implant failure associated with actinomycosis. A 55-year-old Caucasian male patient had tooth #20 extracted years ago and an implant placed 3 years ago. The #20 implant area developed an abscess about 1½ years after implant placement. Radiographic findings revealed a large radiolucency on the mesial aspect of the #20 implant. The implant was surgically removed and the lesion thoroughly debrided. The patient experienced severe pain when the apical soft tissue was curreted following implant removal. A periapical radiograph revealed that the lesion approached the mental foramen. A short course of antibiotics was prescribed. Histological observation found sulfur granules, which were found to be actinomycotic colonies. Peri-implant actinomycosis was diagnosed. No recurrence had occurred at the 1-year follow-up.


Subject(s)
Actinomycosis/diagnosis , Dental Implants , Dental Restoration Failure , Periapical Abscess/microbiology , Hepatitis C/complications , Hepatitis C/drug therapy , Herpes Genitalis/complications , Humans , Male , Middle Aged , Molar/surgery , Periapical Periodontitis/microbiology , Prosthesis-Related Infections/diagnosis , Radiography, Bitewing , Tooth Extraction , Tooth Loss/rehabilitation
16.
Chin J Dent Res ; 14(2): 113-20, 2011.
Article in English | MEDLINE | ID: mdl-22319752

ABSTRACT

OBJECTIVE: To elucidate the aetiology of periodontitis, this study focused on the adenosine receptor (AR) expression profiles (A1AR, A2AAR, A2BAR and A3AR) in periodontal diseased tissues. METHODS: Adenosine receptor gene expression levels in human gingiva from 15 patients with healthy gingival tissues (control group) and 15 patients who exhibited severe chronic periodontitis (test group) were measured using quantitative reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: The mRNA expression pattern changed in human chronic periodontitis: the A1AR decreased 20%, A2AAR increased 2.5-fold, A2BAR increased 3.7-fold and A3AR decreased 70% as compared with that of healthy gingiva. CONCLUSION: Inflammation of the gingival tissue is associated with (1) an unchanged expression of A1AR, (2) an increased expression of A2AAR and A2BAR, and (3) a decreased expression of A3AR. Logistic regression analysis indicated that the change in the expression patterns can be used to diagnose/predict periodontitis. This finding indicates that the adenosine receptor expression profile is changed in periodontitis with the potential for future clinical application.


Subject(s)
Chronic Periodontitis/metabolism , RNA, Messenger/analysis , Receptors, Purinergic P1/analysis , Adult , Aged , Aged, 80 and over , Alveolar Bone Loss/metabolism , Chronic Periodontitis/genetics , Female , Gingiva/metabolism , Gingival Hemorrhage/metabolism , Gingivitis/metabolism , Humans , Male , Middle Aged , Periodontal Attachment Loss/metabolism , Real-Time Polymerase Chain Reaction , Receptor, Adenosine A1/analysis , Receptor, Adenosine A1/genetics , Receptor, Adenosine A2A/analysis , Receptor, Adenosine A2A/genetics , Receptor, Adenosine A2B/analysis , Receptor, Adenosine A2B/genetics , Receptor, Adenosine A3/analysis , Receptor, Adenosine A3/genetics , Receptors, Purinergic P1/genetics , Reverse Transcriptase Polymerase Chain Reaction , Young Adult
17.
J Immunol ; 186(2): 1097-106, 2011 Jan 15.
Article in English | MEDLINE | ID: mdl-21149612

ABSTRACT

Adenosine is an extracellular signaling molecule that is generated in response to cell injury where it orchestrates tissue protection and repair. Whereas adenosine is best known for promoting anti-inflammatory activities during acute injury responses, prolonged elevations can enhance destructive tissue remodeling processes associated with chronic disease states. The generation of adenosine and the subsequent activation of the adenosine 2B receptor (A(2B)R) is an important processes in the regulation of both acute and chronic lung disease. The goal of this study was to examine the contribution of the A(2B)R in models of bleomycin-induced lung injury that exhibit varying degrees of acute and chronic injury. Intratracheal bleomycin exposure results in substantial acute lung injury followed by progressive fibrosis. In this model, genetic removal of the A(2B)R resulted in enhanced loss of barrier function and increased pulmonary inflammation, with few differences in indexes of pulmonary fibrosis. These results support an anti-inflammatory role for this receptor in this model of acute lung injury. In contrast, systemic exposure of mice to bleomycin resulted in modest acute lung injury together with progressive pulmonary fibrosis. In this model, the effects of A(2B)R removal on acute lung injury were negligible; however, there were substantial reductions in pulmonary fibrosis, supporting a profibrotic role for this receptor. A(2B)R-dependent regulation of IL-6 production was identified as a potential mechanism involved in the diminished pulmonary fibrosis seen in A(2B)R knockout mice exposed to i.p. bleomycin. These studies highlight the distinct roles of A(2B)R signaling during acute and chronic stages of lung injury.


Subject(s)
Acute Lung Injury/chemically induced , Acute Lung Injury/metabolism , Bleomycin/toxicity , Receptor, Adenosine A2B/physiology , Acute Disease , Acute Lung Injury/pathology , Animals , Chronic Disease , Inflammation Mediators/metabolism , Inflammation Mediators/physiology , Intubation, Intratracheal , Lung/drug effects , Lung/metabolism , Lung/pathology , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Pulmonary Fibrosis/chemically induced , Pulmonary Fibrosis/metabolism , Pulmonary Fibrosis/pathology , Receptor, Adenosine A2B/deficiency , Receptor, Adenosine A2B/genetics
18.
Chin J Dent Res ; 13(1): 71-5, 2010.
Article in English | MEDLINE | ID: mdl-20936196

ABSTRACT

Hyperplastic dental follicle is an extremely rare lesion. The practitioner should be able to differentiate it from a dentigerous cyst. The present article will review related literature and report on two cases in one family. A 12-year-old white female and her 15-year-old brother were referred for exposure of unerupted canines. No systemic diseases or syndromes were present. Intra-oral examinations were unremarkable, except for the absence of all eight canines. Radiographic examinations revealed impacted canines with each unerupted tooth surrounded by a well-demarcated radiolucency, which passed beyond the cementoenamel junction. The teeth were surgically exposed and tissue specimens surrounding the unerupted teeth were analysed histologically. Histology revealed fibrous connective tissue with areas demonstrating some ground substance and multiple odontogenic epithelial rests. Some surfaces were partially lined by reduced enamel epithelium. A diagnosis of hyperplastic dental follicle was made. Sometimes, it is difficult to differentiate hyperplastic dental follicle from odontogenic fibroma, both simple and central forms. A correct diagnosis should be based on clinical, radiographic and histological findings.


Subject(s)
Dental Sac/pathology , Tooth, Impacted/etiology , Adolescent , Child , Cuspid/pathology , Cuspid/surgery , Dental Sac/surgery , Dentigerous Cyst/diagnosis , Diagnosis, Differential , Female , Humans , Hyperplasia/complications , Hyperplasia/genetics , Hyperplasia/surgery , Male , Odontogenic Tumors/diagnosis , Orthodontic Extrusion , Siblings , Tooth, Impacted/surgery
19.
J Immunol ; 182(12): 8037-46, 2009 Jun 15.
Article in English | MEDLINE | ID: mdl-19494329

ABSTRACT

Adenosine is a signaling nucleoside that is generated in response to cellular injury and orchestrates the balance between tissue protection and the progression to pathological tissue remodeling. Adenosine deaminase (ADA)-deficient mice develop progressive airway inflammation and remodeling in association with adenosine elevations, suggesting that adenosine can promote features of chronic lung disease. Furthermore, pharmacological studies in ADA-deficient mice demonstrate that A(2B)R antagonism can attenuate features of chronic lung disease, implicating this receptor in the progression of chronic lung disease. This study examines the contribution of A(2B)R signaling in this model by generating ADA/A(2B)R double-knockout mice. Our hypothesis was that genetic removal of the A(2B)R from ADA-deficient mice would lead to diminished pulmonary inflammation and damage. Unexpectedly, ADA/A(2B)R double-knockout mice exhibited enhanced pulmonary inflammation and airway destruction. Marked loss of pulmonary barrier function and excessive airway neutrophilia are thought to contribute to the enhanced tissue damage observed. These findings support an important protective role for A(2B)R signaling during acute stages of lung disease.


Subject(s)
Adenosine Deaminase/deficiency , Adenosine Deaminase/metabolism , Pneumonia/immunology , Pneumonia/metabolism , Receptor, Adenosine A2B/metabolism , Adenosine Deaminase/genetics , Animals , Cell Adhesion Molecules/metabolism , Collagen/biosynthesis , Cytokines/biosynthesis , Cytokines/immunology , Female , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Pneumonia/genetics , Pneumonia/pathology , Receptor, Adenosine A2B/deficiency , Receptor, Adenosine A2B/genetics , Receptor, Adenosine A2B/immunology
20.
Blood ; 110(7): 2685-95, 2007 Oct 01.
Article in English | MEDLINE | ID: mdl-17525287

ABSTRACT

We recently showed that A(2A) adenosine receptor activation by endogenous adenosine contributes to interleukin-10 (IL-10) production in polymicrobial sepsis. Here we investigated the molecular mechanisms underpinning this interaction between adenosine receptor signaling and infection by exposing macrophages to Escherichia coli. We demonstrated using receptor knockout mice that A(2A) receptor activation is critically required for the stimulatory effect of adenosine on IL-10 production by E coli-challenged macrophages, whereas A(2B) receptors have a minor role. The stimulatory effect of adenosine on E coli-induced IL-10 production did not require toll-like receptor 4 (TLR4) or MyD88, but was blocked by p38 inhibition. Using shRNA we demonstrated that TRAF6 impairs the potentiating effect of adenosine. Measuring IL-10 mRNA abundance and transfection with an IL-10 promoter-luciferase construct indicated that E coli and adenosine synergistically activate IL-10 transcription. Sequential deletion analysis and site-directed mutagenesis of the IL-10 promoter revealed that a region harboring C/EBP binding elements was responsible for the stimulatory effect of adenosine on E coli-induced IL-10 promoter activity. Adenosine augmented E coli-induced nuclear accumulation and DNA binding of C/EBPbeta. C/EBPbeta-deficient macrophages failed to produce IL-10 in response to adenosine and E coli. Our results suggest that the A(2A) receptor-C/EBPbeta axis is critical for IL-10 production after bacterial infection.


Subject(s)
CCAAT-Enhancer-Binding Protein-beta/metabolism , Escherichia coli/physiology , Interleukin-10/biosynthesis , Macrophages/metabolism , Receptor, Adenosine A2A/metabolism , 5' Flanking Region/genetics , Adenosine/pharmacology , Animals , CCAAT-Enhancer-Binding Protein-beta/genetics , Cells, Cultured , Enzyme Activation , Interleukin-10/genetics , Interleukin-10/metabolism , Macrophages/drug effects , Male , Mice , Myeloid Differentiation Factor 88/metabolism , Promoter Regions, Genetic/genetics , RNA, Messenger/genetics , TNF Receptor-Associated Factor 6/metabolism , Toll-Like Receptor 4/metabolism , p38 Mitogen-Activated Protein Kinases/metabolism
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