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Crystal Violet Staining (crystal + violet_staining)
Selected AbstractsRelationship between histopathological features and type V pit pattern determined by magnifying videocolonoscopy in early colorectal carcinomaDIGESTIVE ENDOSCOPY, Issue 2 2005Shiro Oka Background: The aim of the present study was to clarify the relationship between the histopathological features and type V pit pattern of early colorectal carcinoma. Methods: We examined the relationship between the type V pit pattern subtypes, the depth of submucosal invasion and the degrees of desmoplastic reaction, residual pit density and destruction of the intervening membrane between pits on the tumor surface in 135 cases of early colorectal carcinoma. The examinations involved magnifying videoendoscopy with indigo carmine dye spraying and crystal violet staining. The pit patterns were classified as one of two grades (VI, VN), and VN was further divided into three subtypes (A, B and C). The data obtained were evaluated by ,2 test, with significance accepted at < 0.05% for each analysis. Results: There were 64 VI, 24 VN -A, 28 VN -B and 19 VN -C lesions. The incidence of massive submucosal invasion (sm2, sm3) was significantly higher in VN -B and VN -C lesions than in VI and VN -A lesions (P < 0.05). Among VN pit pattern lesions, depth of submucosal invasion of VN -B and VN -C lesions was significantly greater than that of VN -A lesions (P < 0.01). The incidence of severe desmoplastic reaction in VN -B and VN -C lesions was significantly greater than that in VI lesions (P < 0.01). The incidence of severe desmoplastic reaction in VN -C lesions was significantly greater than that in VN -A lesions (P < 0.05). The incidence of low residual pit density in VN -C lesions was significantly greater than that in all other type V lesions. The incidence of mild to moderate and severe destruction of the intervening membrane between pits in VN lesions was significantly higher than that in VI lesions. Conclusions: Type V pit pattern subclassification is useful for predicting the depth of submucosal invasion in early colorectal carcinomas. The type V pit pattern subtypes are related to the degrees of desmoplastic reaction, the residual pit density and destruction of the intervening membrane between pits on the tumor surface. [source] Engineered measles virus as a novel oncolytic viral therapy system for hepatocellular carcinoma,HEPATOLOGY, Issue 6 2006Boris Blechacz The oncolytic measles virus Edmonston strain (MV-Edm), a nonpathogenic virus targeting cells expressing abundant CD46, selectively destroys neoplastic tissue. Clinical development of MV-Edm would benefit from noninvasive monitoring strategies to determine the speed and extent of the spread of the virus in treated patients and the location of virus-infected cells. We evaluated recombinant MV-Edm expressing carcinoembryonic antigen (CEA) or the human sodium iodide symporter (hNIS) for oncolytic potential in hepatocellular carcinoma (HCC) and efficiency in tracking viruses in vivo by noninvasive monitoring. CD46 expression in human HCC and primary hepatocytes was assessed by flow cytometry and immunohistochemistry. Infectivity, syncytium formation, and cytotoxicity of recombinant MV-Edm in HCC cell lines were evaluated by fluorescence microscopy, crystal violet staining, and the MTS assay. Transgene expression in HCC cell lines after infection with recombinant MV-Edm in vitro and in vivo was assessed by CEA concentration, 125I-uptake, and 123I-imaging studies. Toxicology studies were performed in IfnarKO×CD46 transgenic mice. The CD46 receptor was highly expressed in HCC compared to nonmalignant hepatic tissue. Recombinant MV-Edm efficiently infected HCC cell lines, resulting in extensive syncytium formation followed by cell death. Transduction of HCC cell lines and subcutaneous HCC xenografts with recombinant MV-Edm resulted in high-level expression of transgenes in vitro and in vivo. MV-Edm was nontoxic in susceptible mice. Intratumoral and intravenous therapy with recombinant MV-Edm resulted in inhibition of tumor growth and prolongation of survival with complete tumor regression in up to one third of animals. In conclusion, engineered MV-Edm may be a potent and novel cancer gene therapy system for HCC. MV-Edm expressing CEA or hNIS elicited oncolytic effects in human HCC cell lines in vitro and in vivo, enabling the spread of the virus to be monitored in a noninvasive manner. (HEPATOLOGY 2006;44:1465,1477.) [source] Influence of temperature on biofilm formation by Listeria monocytogenes on various food-contact surfaces: relationship with motility and cell surface hydrophobicityJOURNAL OF APPLIED MICROBIOLOGY, Issue 6 2008G. Di Bonaventura Abstract Aims:, To assess the ability of Listeria monocytogenes to form biofilm on different food-contact surfaces with regard to different temperatures, cellular hydrophobicity and motility. Methods and Results:, Forty-four L. monocytogenes strains from food and food environment were tested for biofilm formation by crystal violet staining. Biofilm levels were significantly higher on glass at 4, 12 and 22°C, as compared with polystyrene and stainless steel. At 37°C, L. monocytogenes produced biofilm at significantly higher levels on glass and stainless steel, as compared with polystyrene. Hydrophobicity was significantly (P < 0·05) higher at 37°C than at 4, 12 and 22°C. Thirty (68·2%) of 44 strains tested showed swimming at 22°C and 4 (9·1%) of those were also motile at 12°C. No correlation was observed between swimming and biofilm production. Conclusions:,L. monocytogenes can adhere to and form biofilms on food-processing surfaces. Biofilm formation is significantly influenced by temperature, probably modifying cell surface hydrophobicity. Significance and Impacts of the Study:, Biofilm formation creates major problems in the food industry because it may represent an important source of food contamination. Our results are therefore important in finding ways to prevent contamination because they contribute to a better understanding on how L. monocytogenes can establish biofilms in food industry and therefore survive in the processing environment. [source] Berberine inhibits Staphylococcus Epidermidis adhesion and biofilm formation on the surface of titanium alloyJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 11 2009Xiaoqing Wang Abstract Biofilm formed by Staphylococcus epidermidis (S. epidermidis) is a common cause of periprosthetic infection. Recently, we have discovered that berberine is bacteriostatic for S. epidermidis. The purpose of the present study was to examine the effect of berberine on S. epidermidis adhesion and biofilm formation on the surface of titanium alloy, which is a popular material for orthopedic joint prostheses. Three strains of S. epidermidis (ATCC 35984, ATCC 12228, and SE 243) were used for in vitro experiment. Direct colony counting showed that berberine significantly inhibited S. epidermidis adhesion on the titanium alloy disk in 2 h at the concentration of 45 µg/mL. When examined with crystal violet staining, confocal laser scanning microscopy, and scanning electron microscopy, we found that higher concentrations (>30 µg/mL) of berberine effectively prevented the formation of S. epidermidis biofilm on the surface of the titanium disk in 24 h. These findings suggest that berberine is a potential agent for the treatment of periprosthetic infection. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27:1487,1492, 2009 [source] Influences of milk components on biofilm formation of Cronobacter spp. (Enterobacter sakazakii)LETTERS IN APPLIED MICROBIOLOGY, Issue 6 2009G.I. Dancer Abstract Aim:, To determine the critical component(s) of skim milk for biofilm formation of Cronobacter species. Methods and Results:, Biofilm forming ability of 72 Cronobacter strains in skim milk preparation was assayed by crystal violet staining. The results revealed that whey protein and casein are more important determinants of skim milk for biofilm formation than lactose, although there was a wide variation in biofilm forming ability. Biofilm structure and capsular material of six strains exhibiting different biofilm forming ability was investigated via electron microscopes. Scanning electron microscopy showed visually that while the strong biofilm formers (E27B, FSM 30 and 2·82) resulted in almost complete coagulation of skim milk, the weak biofilm formers (55, FSM 290 and 2·84) caused less coagulation. No capsule was clearly delineated in transmission electron micrographs of either strong or weak biofilm formers. Conclusion:, These results indicate that, for biofilm formation of Cronobacter species in skim milk, nitrogen source is probably a more important determinant than carbohydrate, and that strong biofilm formers are responsible for substantial coagulation of skim milk. Significance and Impact of the Study:, This study provides information for better understanding of the underlying mechanisms by which Cronobacter species form biofilm in infant formula milk. [source] Biofilm formation by Streptococcus pneumoniae isolates from paediatric patientsAPMIS, Issue 4 2010TERHI TAPIAINEN Tapiainen T, Kujala T, Kaijalainen T, Ikäheimo I, Saukkoriipi A, Renko M, Salo J, Leinonen M, Uhari M. Biofilm formation by Streptococcus pneumoniae isolates from paediatric patients. APMIS 2010; 118: 255,60. The clinical significance of pneumococcal biofilm formation is largely unknown. To clarify this, we tested whether the ability of pneumococcal clinical isolates to form biofilm in vitro accounts for the diverse clinical outcomes. Clinical pneumococcal isolates were cultured from the nasopharynx (n = 106), middle ear effusion (n = 43) and blood (n = 55) of 204 children altogether. Biofilm formation, assessed by measuring optical density (OD) values in microtitre plates after crystal violet staining, did not differ between the bacteria from different sources (p = 0.18), the mean OD values of the isolates being 0.119 [95% confidence interval (CI) 0.100,0.138] in the nasopharynx samples, 0.094 (95% CI 0.069,0.119) in the acute otitis media cases, 0.109 (95% CI 0.077,0.141) in the secretory otitis media cases, 0.122 (95% CI 0.084,0.160) in those with sepsis and 0.175 (95% CI 0.071,0.280) in those with other invasive infections. Serotypes 33 and 14 were the most efficient in forming biofilms, whereas serotypes 3 and 38 were poor biofilm producers. We conclude that the clinical presentation of pneumococcal disease did not differ in relation to biofilm formation in vitro, even though there was marked variation between the clinical isolates and serotypes. [source] In vitro evaluation of bevacizumab toxicity on a retinal ganglion cell lineACTA OPHTHALMOLOGICA, Issue 6 2009Rajesh K. Sharma Abstract. Purpose:, The effects of bevacizumab on cell viability and proliferation in a commonly used retinal ganglion cell line, RGC-5, were examined. Methods:, RGC-5 cells were exposed to 0.1 mg/ml, 1 mg/ml and 2 mg/ml of commercially available bevacizumab in vitro. To examine the specificity of effects, cells were also cultured with increasing and comparable concentrations of proteins (increasing the concentration of proteins in the culture media by 0.1 mg/ml, 1 mg/ml and 2 mg/ml by using additional fetal bovine serum [FBS] and bovine serum albumin [BSA]). Cell proliferation was assessed using a WST-1 kit, crystal violet staining and bromodeoxyuridine (BrdU) incorporation. Cytotoxic effects were assessed by quantifying cell numbers in proliferation-deficient RGC-5 following exposure to bevacizumab using the WST-1 kit, microscopic examination of cells stained with propidium iodide (PI) cells and flow cytometry for differential staining with PI. Results:, Bevacizumab was not toxic to RGC-5 cells in the tested concentrations. It had a stimulatory effect on cell proliferation. A stimulatory effect on proliferation was also noted when equivalent amounts of proteins from FBS or BSA were used, which suggests that bevacizumab may stimulate proliferation non-specifically by increasing the protein contents of the cell growth environment. Conclusions:, Results suggest that intravitreal injection of bevacizumab could alter the internal milieu of the eye by increasing protein concentrations to elicit functional responses in retinotypic cells. This may be especially relevant for cells outwith the control of vascular endothelial growth factor. [source] | |||||||||||||