The objective of this study is to propose a more accurate and faster MTT [3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide] colorimetric assay (MCA) for quantitative measurement of polypeptide bacteriocins in solutions with nisin as an example. After an initial incubation of nisin and indicator bacterium Micrococcus luteus NCIB 8166 in tubes, MTT was added for another incubation period. After that, nisin was quantified by estimating the number of viable bacteria based on measuring the amount of purple formazan produced by cleavage of yellow tetrazolium salt MTT. Then MCA was compared to a standard agar diffusion assay (ADA). The results suggested a high correlation coefficient (r(2)=0.975+/-0.004) between optical density (OD) and the inhibitory effect of nisin on a bacterial strain Micrococcus luteus NCIB 8166 at a range of 0.125-32 IU/ml. The MCA described in this study was very quick. Quantification of nisin took only 7-8 h and the detection limit was at the level of 0.125 IU/ml when compared to 12 IU/ml and 24-28 h for ADA. The MCA provides an accurate and rapid method for quantification of nisin in solutions and is expected to be used for quantification of other antimicrobial substances.
Bacteriocins ; analysis ; metabolism ; Colorimetry ; methods ; Immunodiffusion ; Micrococcus luteus ; metabolism ; Nisin ; Regression Analysis ; Tetrazolium Salts ; analysis ; Thiazoles ; analysis ; Time Factors

PURPOSE: Polymethyl methacrylate (PMMA) is the most commonly used denture base material despite typically low in strength. The purpose of this study was to improve the physical properties of the PMMA based denture base resins (QC-20, Dentsply Ltd., Addlestone, UK; Stellon, AD International Ltd, Dentsply, Switzerland; Acron MC; GC Lab Technologies Inc., Alsip, Japan) by copolymerization mechanism. MATERIALS AND METHODS: Control group specimens were prepared according to the manufacturer recommendations. In the copolymer groups; resins were prepared with 5%, 10%, 15% and 20% acrylamide (AAm) (Merck, Hohenbrunn, Germany) content according to the moleculer weight ratio, respectively. Chemical structure was characterized by a Bruker Vertex-70 Fourier transform infrared spectroscopy (FTIR) (Bruker Optics Inc., Ettlingen, Germany). Hardness was determined using an universal hardness tester (Struers Duramin, Struers A/S, Ballerup, Denmark) equipped with a Vickers diamond penetrator. The glass transition temperature (Tg) of control and copolymers were evaluated by Perkin Elmer Diamond DSC (Perkin Elmer, Massachusetts,USA). Statistical analyses were carried out using the statistical package SPSS for Windows, version 15.0 (SPSS, Chicago, IL, USA). The results were tested regarding the normality of distribution with the Shapiro Wilk test. Data were analyzed using ANOVA with post-hoc Tukey test (P<.01). RESULTS: The copolymer synthesis was confirmed by FTIR spectroscopy. Glass transition temperature of the copolymer groups were higher than the control groups of the resins. The 10%, 15% and 20% copolymer groups of Stellon presented significantly higher than the control group in terms of hardness. 15% and 20% copolymer groups of Acron MC showed significantly higher hardness values when compared to the control group of the resin. Acrylamide addition did not affect the hardness of the QC-20 resin significantly. CONCLUSION: Within the limitation of this study, it can be concluded that copolymerization of PMMA with AAm increased the hardness value and glass transition temperature of PMMA denture base resins.
Acrylamide ; Acrylic Resins ; Chicago ; Collodion ; Denture Bases ; Dentures ; Diamond ; Glass ; Hardness ; Hardness Tests ; Polymethyl Methacrylate ; Pyridines ; Spectroscopy, Fourier Transform Infrared ; Spectrum Analysis ; Thiazoles ; Transition Temperature

PURPOSE: Features of epidermal growth factor receptor (EGFR) expression in osteosarcoma and in vitro efficacies of EGFR inhibitors against osteosarcoma cells were evaluated. MATERIALS AND METHODS: Thirty biopsy samples of osteosarcoma patients were retrospectively analyzed for EGFR protein expression by immunohistochemistry. Relationships between EGFR expression and clinicopathologic characteristics and treatment outcomes were evaluated. Four osteosarcoma cell lines were analyzed for EGFR and p-EGFR expression by western blotting. Efficacies of gefitinib and BIBW2992 on osteosarcoma cells were evaluated using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Tyrosine kinase domains in exons 18 to 21 were sequenced and gene expression analyses of EGFR and PTEN were performed in four osteosarcoma cell lines. RESULTS: EGFR protein was expressed in 27 (90%) samples (6 low, 12 intermediate, 9 high) and in three cell lines. Intermediate or high staining for EGFR was related to a tumor volume<150 mL (p<0.001) and histologic subtype other than osteoblastic type (p=0.03). However, EGFR expression was not associated with histologic response to preoperative chemotherapy or survival. Gefitinib and BIBW 2992 did not have any significant inhibitory effect on cell viabilities. DNA sequencing analysis revealed three osteosarcoma cell lines have single base changes at codon 2361 of exon 20 (G to A), without affecting translation results. Furthermore, no mutation was found to be associated with constitutive EGFR activation. CONCLUSION: In the present study, gefitinib and BIBW2992 were not effective against osteosarcoma cells. However, as osteosarcoma cells express EGFR, further studies are necessary to explore the potential of other therapeutic agents targeting EGFR.
Biopsy ; Blotting, Western ; Cell Line ; Cell Survival ; Codon ; Epidermal Growth Factor ; Exons ; Gene Expression ; Humans ; Immunohistochemistry ; Osteoblasts ; Osteosarcoma ; Protein-Tyrosine Kinases ; Quinazolines ; Receptor, Epidermal Growth Factor ; Retrospective Studies ; Sequence Analysis, DNA ; Tetrazolium Salts ; Thiazoles

Disseminated superficial porokeratosis (DSP) is a rare cause of secondary cutaneous amyloidosis. An 83-year-old male patient showed an increase in both size and number of DSP lesions after contracting pulmonary tuberculosis. The DSP lesions of the patient consisted of numerous annular eruptions on both sun-exposed and sun-protected areas, which occurred over a period of 20 years. Multiple skin biopsies were taken from normal or lesional/sun-exposed or sun-protected skin samples. Histopathologic examination included routine H+ACY-E stains, Congo red stains, thioflavin-T stains and anticytokeratin antibodies (AE1, AE3). And the results were as follows+ADs- 1) Positive staining with Congo red and thioflavin-T indicated an amyloid nature for the deposits, 2) confinement of the amyloid deposition just below the lesional epidermis (while sparing the neighboring uninvolved or distant normal skin) indicated some role of the lesional epidermis, and 3) positive staining with AE3 further indicated an epidermal origin-type II epithelial keratin-of the amyloid. We present a case of DSP with a local amyloid deposit, characterized by association of positive familial background, severe pruritus and pulmonary tuberculosis.
Aged ; Aged, 80 and over ; Amyloid/analysis ; Amyloidosis/etiology+ACo- ; Case Report ; Congo Red ; Dyes ; Epidermis/chemistry ; Human ; Male ; Porokeratosis/complications+ACo- ; Pruritus/etiology ; Skin Diseases/etiology+ACo- ; Staining and Labeling ; Thiazoles ; Tuberculosis, Pulmonary/complications

Disseminated superficial porokeratosis (DSP) is a rare cause of secondary cutaneous amyloidosis. An 83-year-old male patient showed an increase in both size and number of DSP lesions after contracting pulmonary tuberculosis. The DSP lesions of the patient consisted of numerous annular eruptions on both sun-exposed and sun-protected areas, which occurred over a period of 20 years. Multiple skin biopsies were taken from normal or lesional/sun-exposed or sun-protected skin samples. Histopathologic examination included routine H+ACY-E stains, Congo red stains, thioflavin-T stains and anticytokeratin antibodies (AE1, AE3). And the results were as follows+ADs- 1) Positive staining with Congo red and thioflavin-T indicated an amyloid nature for the deposits, 2) confinement of the amyloid deposition just below the lesional epidermis (while sparing the neighboring uninvolved or distant normal skin) indicated some role of the lesional epidermis, and 3) positive staining with AE3 further indicated an epidermal origin-type II epithelial keratin-of the amyloid. We present a case of DSP with a local amyloid deposit, characterized by association of positive familial background, severe pruritus and pulmonary tuberculosis.
Aged ; Aged, 80 and over ; Amyloid/analysis ; Amyloidosis/etiology+ACo- ; Case Report ; Congo Red ; Dyes ; Epidermis/chemistry ; Human ; Male ; Porokeratosis/complications+ACo- ; Pruritus/etiology ; Skin Diseases/etiology+ACo- ; Staining and Labeling ; Thiazoles ; Tuberculosis, Pulmonary/complications

OBJECTIVEp53-induced apoptosis is crucial in the development of hypoxic-ischemia (HI) brain damage and neurodegenerative disorders. Some experimental research has shown that a synthetic inhibitor of p53 can protect neurons against apoptosis. This study aimed to explore the expression of p53 in neonatal mice following HI brain damage and the effect of p53 inhibitor (pifithrin-alpha, PFT-alpha) on brain damage.

METHODSHI was induced in 9-day-old mice pups by ligation of left carotid artery and 10% oxygen exposure for 55 minutes. The pups were sacrificed and the brains were taken out at 3, 8, 24, and 72 hrs post-HI. The brains were sectioned and stained with antibody against p53 and microtubule-associated protein 2 (MAP-2). PFT-alpha was injected intraperitoneally: in experiment 1, immediately after HI with different dosages (1, 2 and 8 mg/kg); in experiment 2, 2 mg/kg at different HI times (1 hr before HI, and immediately and 1 hr after HI). Control animals without HI received injections of 0.5% dimethyl sulfoxide. Brain damage was evaluated by gross morphology scoring at 72 hrs after HI.

RESULTSThe number of p53 positive cells in the cortex, hippocampus and striatum of the ipsilateral hemisphere increased significantly and peaked at 3-8 hrs post-HI when compared with those of contralateral hemisphere as well as normal controls. The positive cells distributed mainly in the MAP-2 negative area. Both different dosages and different injection time PFT-alpha treatment did not reduce the extent of brain damage.

CONCLUSIONSThe immunoactivity of p53 increased significantly as early as 3 hrs post-HI. The distribution area of p53 expression was consistent with that of brain damage. The p53 inhibitor PFT-alpha has no protective effects against HI brain damage in neonatal mice.

Animals ; Animals, Newborn ; Benzothiazoles ; Brain ; drug effects ; pathology ; Dose-Response Relationship, Drug ; Female ; Hypoxia-Ischemia, Brain ; metabolism ; Immunohistochemistry ; Male ; Mice ; Mice, Inbred C57BL ; Thiazoles ; pharmacology ; Toluene ; analogs & derivatives ; pharmacology ; Tumor Suppressor Protein p53 ; analysis ; antagonists & inhibitors

OBJECTIVEWe designed a multi-center, double-blind, randomized, parallel, with metformin controlled clinical trial to evaluate the efficacy and safety of low dose rosiglitazone combined with sulphonylurea therapy in type 2 diabetic patients who were inadequately controlled with sulphonylurea alone.

METHODSPatients were treated with 4 mg rosiglitazone once daily plus sulphonylurea (test group) or 0.5 g metformin twice daily plus sulphonylurea (control group) for 12 weeks. The mean levels of HbA(1c), fasting and postprandial plasma glucose were recorded and compared between the two groups.

RESULTSThe mean levels of HbA(1c) decreased by 1.09% and 0.95% in the test group (n = 102) and control group (n = 96) respectively. Fasting and postprandial plasma glucose levels in the test group decreased by 25.0% and 35.6%, and in the control group, decreased by 17.7% and 23.8% as compared with the baseline (both P < 0.01). No liver damage was found.

CONCLUSIONCombination treatment of rosiglitazone and sulphonylurea can effectively improve glycemic control in type 2 diabetic patients inadequately controlled with sulphonylurea alone.

Adult ; Aged ; Blood Glucose ; analysis ; Diabetes Mellitus, Type 2 ; drug therapy ; Double-Blind Method ; Drug Therapy, Combination ; Humans ; Hypoglycemic Agents ; administration & dosage ; Metformin ; administration & dosage ; Middle Aged ; Sulfonylurea Compounds ; administration & dosage ; Thiazoles ; administration & dosage ; Thiazolidinediones

AIMTo detect the expression of HSP25 in rat dental follicles both in vivo and vitro, and explore the underlying mechanism of HSP25 on the proliferation and differentiation of rat dental follicle cells (DFCs).

METHODOLOGYImmunohistochemistry was performed to detect the expression of HSP25 in mandibles of postnatal rats on days 1, 3, 5, 7, 9 and 11 in vivo. In vitro, the expression of HSP25 in DFCs was detected by an indirect immunofluorescence assay. Thiazolyl blue tetrazolium bromide (MTT) assay, flow cytometry and alkaline phosphatase (ALP) assay were used to identify the time-course effect mediated by different concentrations of recombinant murine HSP25 of 0, 1, 10, 50 and 100 ng/mL on rat DFCs.

RESULTSExpression of HSP25 was not detected in dental follicles of the rats until day 5 after birth, but became up-regulated in a time-dependent manner till day 11. HSP25 was detected in the cytoplasm of cultured rat DFCs. No significant difference could be observed in the proliferation of DFCs after stimulation with different concentrations of HSP25 on days 1, 2 and 3 (P > 0.05). HSP25 at concentrations of 50 ng/mL and 100 ng/mL up-regulated the ALP activity of DFCs on day 9 (P < 0.05).

CONCLUSIONHSP25-immunoreactivity increased chronologically during the development of dental follicles. The protein had no significant effect on cell proliferation but may play a role in cementoblast/osteoblast differentiation of DFCs.

Alkaline Phosphatase ; analysis ; Ameloblasts ; cytology ; Animals ; Cell Culture Techniques ; Cell Differentiation ; physiology ; Cell Proliferation ; Coloring Agents ; Cytoplasm ; ultrastructure ; Dental Sac ; cytology ; growth & development ; Flow Cytometry ; Fluorescent Antibody Technique, Indirect ; HSP27 Heat-Shock Proteins ; analysis ; physiology ; Odontoblasts ; cytology ; Rats ; Rats, Sprague-Dawley ; Tetrazolium Salts ; Thiazoles ; Tooth Germ ; cytology ; Up-Regulation ; physiology

PURPOSE: We have used a genetically attenuated adenoviral vector which expresses HSVtk to assess the possible additive role of suicidal gene therapy for enhanced oncolytic effect of the virus. Expression of TK was measured using a radiotracer-based molecular counting and imaging system. MATERIALS AND METHODS: Replication-competent recombinant adenoviral vector (Ad-deltaE1B19/55) was used in this study, whereas replication-incompetent adenovirus (Ad-deltaE1A) was generated as a control. Both Ad-deltaE1B19/55-TK and Ad-deltaE1A-TK comprise the HSVtk gene inserted into the E3 region of the viruses. YCC-2 cells were infected with the viruses and incubated with 2'-deoxy-2'-fluoro-beta-D-arabinofuranosyl-5-iodouracil (I-131 FIAU) to measure amount of radioactivity. The cytotoxicity of the viruses was determined, and gamma ray imaging of HSVtk gene was performed. MTT assay was also performed after GCV treatment. RESULTS: On gamma counter-analyses, counts/minute (cpm)/microgram of protein showed MOIs dependency with deltaE1B19/55-TK infection. On MTT assay, Ad-deltaE1B19/55-TK led to more efficient cell killing than Ad-deltaE1A-TK. On plate imaging by gamma camera, both Ad-deltaE1B19/55-TK and Ad-deltaE1A-TK infected cells showed increased I-131 FIAU uptake in a MOI dependent pattern, and with GCV treatment, cell viability of deltaE1B19/55-TK infection was remarkably reduced compared to that of Ad-deltaE1A-TK infection. CONCLUSION: Replicating Ad-deltaE1B19/55-TK showed more efficient TK expression even in the presence of higher-cancer cell killing effects compared to non-replicating Ad-deltaE1A-TK. Therefore, GCV treatment still possessed an additive role to oncolytic effect of Ad-deltaE1B19/55-TK. The expression of TK by oncolytic viruses could rapidly be screened using a radiotracer-based counting and imaging technique.
Adenoviridae/*genetics/physiology ; Cell Line, Transformed ; Cell Line, Tumor ; Ganciclovir/pharmacology ; Gene Expression ; Gene Therapy/methods ; Genetic Vectors ; Humans ; *Oncolytic Virotherapy ; Oncolytic Viruses/*genetics/physiology ; Simplexvirus/genetics ; Tetrazolium Salts/analysis ; Thiazoles/analysis ; Thymidine Kinase/*genetics/metabolism ; Transgenes ; Viral Proteins/*genetics/metabolism ; Virus Replication

No abstract available.
Base Sequence ; Benzamides/therapeutic use ; Bone Marrow/pathology ; Female ; Fusion Proteins, bcr-abl/*genetics ; Humans ; Karyotyping ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy/*genetics ; Middle Aged ; Philadelphia Chromosome ; Piperazines/therapeutic use ; Protein Kinase Inhibitors/therapeutic use ; Pyrimidines/therapeutic use ; Sequence Analysis, DNA ; Thiazoles/therapeutic use ; Translocation, Genetic