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Methylene Blue Staining (methylene + blue_staining)
Selected AbstractsMicrochannels created by sugar and metal microneedles: Characterization by microscopy, macromolecular flux and other techniquesJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 4 2010Guohua Li Abstract The objective of this study was to investigate the feasibility of using microneedle technology to enhance transcutaneous permeation of human immunoglobulin G (IgG) across hairless rat skin. Microchannels created by maltose and metal (DermaRollerÔ) microneedles were characterized by techniques such as methylene blue staining, histological examination, and calcein imaging. Methylene blue staining and histological sections of treated skin showed that maltose microneedles and DermaRollerÔ breached the skin barrier by creating microchannels in the skin with an average depth of ,150,µm, as imaged by confocal microscopy. Calcein imaging and pore permeability index values suggested the uniformity of the created pores in microneedle-treated skin. Transdermal studies with IgG indicated a flux rate of 45.96,ng/cm2/h, in vitro, and a Cmax of 7.27,ng/mL, in vivo, for maltose microneedles-treated skin while a flux rate of 353.17,ng/cm2/h, in vitro, and a Cmax of 9.33,ng/mL, in vivo, was achieved for DermaRollerÔ-treated skin. Transepidermal water loss measurements and methylene blue staining, in vivo, indicated the presence of microchannels for upto 24,h, when occluded. In conclusion, the microchannels created by maltose microneedles and DermaRollerÔ resulted in the percutaneous enhancement of a macromolecule, human IgG. © 2009 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 99: 1931,1941, 2010 [source] EX VIVO CASE STUDY OF ENDOCYTOSCOPY IN SUPERFICIAL ESOPHAGEAL CANCERDIGESTIVE ENDOSCOPY, Issue 2007Mototsugu Kato Microscopic observation at the cellular level using endocytoscopy was obtained in surface mucosa of the gastrointestinal tract. This paper describes ex vivo images for endoscopically resected specimens of superficial esophageal cancer using endocytoscopy with methylene blue staining. The endocytoscopy images of cancerous and non-cancerous sites corresponded generally with horizontal histological images. The pattern of the cellular arrangement and the size and shape of cells were similar between endocytoscopy and horizontal histological imaging. Endocytoscopy is an effective tool for diagnosis of esophageal cancer. [source] Microchannels created by sugar and metal microneedles: Characterization by microscopy, macromolecular flux and other techniquesJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 4 2010Guohua Li Abstract The objective of this study was to investigate the feasibility of using microneedle technology to enhance transcutaneous permeation of human immunoglobulin G (IgG) across hairless rat skin. Microchannels created by maltose and metal (DermaRollerÔ) microneedles were characterized by techniques such as methylene blue staining, histological examination, and calcein imaging. Methylene blue staining and histological sections of treated skin showed that maltose microneedles and DermaRollerÔ breached the skin barrier by creating microchannels in the skin with an average depth of ,150,µm, as imaged by confocal microscopy. Calcein imaging and pore permeability index values suggested the uniformity of the created pores in microneedle-treated skin. Transdermal studies with IgG indicated a flux rate of 45.96,ng/cm2/h, in vitro, and a Cmax of 7.27,ng/mL, in vivo, for maltose microneedles-treated skin while a flux rate of 353.17,ng/cm2/h, in vitro, and a Cmax of 9.33,ng/mL, in vivo, was achieved for DermaRollerÔ-treated skin. Transepidermal water loss measurements and methylene blue staining, in vivo, indicated the presence of microchannels for upto 24,h, when occluded. In conclusion, the microchannels created by maltose microneedles and DermaRollerÔ resulted in the percutaneous enhancement of a macromolecule, human IgG. © 2009 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 99: 1931,1941, 2010 [source] Human tissue-engineered bone produced in clinically relevant amounts using a semi-automated perfusion bioreactor system: a preliminary studyJOURNAL OF TISSUE ENGINEERING AND REGENERATIVE MEDICINE, Issue 1 2010F. W. Janssen Abstract The aim of this study was to evaluate a semi-automated perfusion bioreactor system for the production of clinically relevant amounts of human tissue-engineered bone. Human bone marrow stromal cells (hBMSCs) of eight donors were dynamically seeded and proliferated in a perfusion bioreactor system in clinically relevant volumes (10 cm3) of macroporous biphasic calcium phosphate scaffolds (BCP particles, 2,6 mm). Cell load and distribution were shown using methylene blue staining. MTT staining was used to demonstrate viability of the present cells. After 20 days of cultivation, the particles were covered with a homogeneous layer of viable cells. Online oxygen measurements confirmed the proliferation of hBMSCs in the bioreactor. After 20 days of cultivation, the hybrid constructs became interconnected and a dense layer of extracellular matrix was present, as visualized by scanning electron microscopy (SEM). Furthermore, the hBMSCs showed differentiation towards the osteogenic lineage as was indicated by collagen type I production and alkaline phosphatase (ALP) expression. We observed no significant differences in osteogenic gene expression profiles between static and dynamic conditions like ALP, BMP2, Id1, Id2, Smad6, collagen type I, osteocalcin, osteonectin and S100A4. For the donors that showed bone formation, dynamically cultured hybrid constructs showed the same amount of bone as the statically cultured hybrid constructs. Based on these results, we conclude that a semi-automated perfusion bioreactor system is capable of producing clinically relevant and viable amounts of human tissue-engineered bone that exhibit bone-forming potential after implantation in nude mice. Copyright © 2009 John Wiley & Sons, Ltd. [source] RD114-pseudotyped retroviral vectors kill cancer cells by syncytium formation and enhance the cytotoxic effect of the TK/GCV gene therapy strategyTHE JOURNAL OF GENE MEDICINE, Issue 4 2005E. Germain Abstract Background Wild-type RD114 virus is capable of generating syncytia during its replication, and it is believed that cell-free viruses direct the fusion of neighboring cells. The RD114 envelope (Env) that mediates this fusion event is now widely used to pseudotype retroviral and lentiviral vectors in gene therapy. Indeed, vectors pseudotyped with RD114 Env are very efficient to transfer genes into human hematopoietic cells, and they are resistant to human complement inactivation. In this study, we have tested the potential of RD114-pseudotyped vectors produced from the FLYRD18 packaging cell line to induce syncytia. Methods RD114-pseudotyped vectors produced from the FLYRD18 packaging cells were added on tumor cell lines, and the formation of syncytia was assessed by microscopy after cell fixation and methylene blue staining. The kinetics of syncytium formation was analyzed by time-lapse microscopy. Finally, the cytotoxic effect of RD114-pseudotyped vectors was measured by the MTT assay on tumor cells, and in combination with the TK/GCV strategy. Results We have found that these vectors were able to mediate cell-to-cell fusion of human tumor cell lines. A few hours after addition of the vector, cells started to aggregate to form syncytia that eventually evolved toward cell death 48 h postinfection. RD114-pseudotyped vectors were very efficient at killing human cancer cells, and they were also able to enhance dramatically the cytotoxic effect of the TK/GCV strategy. Conclusions These findings indicate that RD114-pseudotyped vectors used alone, or in combination with a suicide gene therapy approach, have great potential for the treatment of cancer. Copyright © 2004 John Wiley & Sons, Ltd. [source] Optimal duration of preoperative anti-helminthic therapy for pulmonary hydatid surgeryANZ JOURNAL OF SURGERY, Issue 5 2010Parvaiz A. Koul Abstract Background:, The optimal duration of preoperative anti-helminths for prevention of recurrences in pulmonary hydatidosis is unclear, although 1,3 weeks of therapy is routinely used. Methods:, Forty-five patients of pulmonary hydatid disease were randomly assigned into four groups to receive either 0, 2, 4 or 8 weeks of preoperative albendazole (ABZ) and praziquantel (PZQ). Viability of the scolices in the fluid harvested at surgery (methylene blue staining) and ability to produce peritoneal hydatids in mice (intra-peritoneal inoculation) were compared in different groups. Results:, The percentage viability of the scolices as a whole was significantly (P < 0.001) lower in the treated cysts (n= 36, mean 43.5 ± 35.69) compared with the untreated cysts (n= 8, mean 94.75 ± 7.21). The viability progressively decreased with increasing durations of chemotherapy (P < 0.001). Mean percentage viability of scolices was 88.72 ± 4.91% in patients treated for 2 weeks (n= 12), 38.09 ± 9.10% after 4 weeks (n= 11) and 8.1 ± 9.23% after 8 weeks (n= 14). Intra-peritoneal mice inoculation was positive in 90% of the cysts that received therapy for 2 weeks or less and none of the patients who received therapy for 8 weeks had a positive inoculation. Conclusions:, Preoperative combination therapy with ABZ and PZQ effects a scolicidal response which increases with the increasing duration of the preoperative chemotherapy, and a 4-week course of the combination chemotherapeutic agents seems to be the minimum required duration for ensuring scolicidal activity enough to prevent spillage-induced recurrences following pulmonary hydatidosis. [source] Diffusion properties of transurethral intraprostatic injectionBJU INTERNATIONAL, Issue 9 2004Mark K. Plante OBJECTIVES To evaluate the location and extent of diffusion that occurs when liquid is injected transurethrally into the prostate gland, by correlating real-time fluoroscopy and gross pathology, and to quantify the variables that influence intraprostatic diffusion during chemoablation of the prostate. MATERIALS AND METHODS A solution of diatrizoate meglumine (HypaqueTM, Nycomed, Princeton, NJ) gentamicin and methylene-blue dye (HGM) was injected transurethrally into the prostate in six dogs, using a passive-deflection needle injection system. The intraprostatic diffusion characteristics were evaluated during each injection using real-time C-arm fluoroscopy, and following each injection by gross examination of methylene blue staining within the prostatic tissues. HGM back-flow into the urethra at the time of injection was assessed by measuring gentamicin levels in the collected bladder irrigant after each injection, using a standard dilution formula. RESULTS There was variability in the intraprostatic diffusion both fluoroscopically and grossly. The needle occasionally assumed a straighter trajectory than its intended curve. Intraprostatic diffusion was detected in 12 of 36 injections (33%). Using standard manipulations of various devices increased the intraprostatic diffusion in these injections to almost 80%. There was less intraprostatic diffusion when the injection resistance was either extremely high or absent. There was no extraprostatic extravasation of HGM beyond the prostatic capsule. CONCLUSION Current methods of transurethral intraprostatic injection are variable for both the diffusion of HGM solution and in needle deployment. The gross diffusion patterns with the HGM solution were consistent with the diffusion patterns documented in our previous research using absolute ethanol. These and other factors may partly explain the variability of the lesions produced with ethanol injection. Therefore, more research is needed to further elucidate the diffusion characteristics of solutions injected intraprostatically using the transurethral approach. [source] | ||||||||||