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Microscopic Evaluation (microscopic + evaluation)
Selected AbstractsDEFINITIVE DIAGNOSIS OF EARLY ENAMEL AND DENTINAL CRACKS BASED ON MICROSCOPIC EVALUATIONJOURNAL OF ESTHETIC AND RESTORATIVE DENTISTRY, Issue 7 2003Joel H. Berg DDS [source] Definitive Diagnosis of Early Enamel and Dentin Cracks Based on Microscopic EvaluationJOURNAL OF ESTHETIC AND RESTORATIVE DENTISTRY, Issue 7 2003DAVID J. CLARK DDS [source] Is the axilla a distinct skin phenotype?INTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 1 2007A. Watkinson The axillary skin is cosmetically important with millions of consumers daily applying antiperspirant/deodorant products. Despite this, we know virtually nothing about axillary skin or how antiperspirant use impacts upon it. To characterize axillary stratum corneum and determine whether this is a unique skin type, we have evaluated a range of skin parameters, comparing these with the volar forearm. Trans-epidermal water loss and corneosurfametry revealed a reduced barrier function in the axilla. However, application of antiperspirant had no effect upon these barrier properties. High performance thin layer chromatography analysis of stratum corneum lipids demonstrated statistically elevated levels of fatty acids, ceramide and particularly cholesterol in the axilla. This modification of barrier lipid ratios appeared to result in a more ordered lipid lamellae phase behaviour, as determined by attenuated total reflectance Fourier transform infrared spectroscopy, with transition phase changes occurring at higher temperatures. Morphological differences were also seen in the cells of the axillary stratum corneum. Microscopic evaluation of axillary-cornified envelopes revealed them to be smaller, indicative of a shorter stratum corneum turnover. However, there appeared to be no significant difference corneocyte maturation. ,Skin dryness' squamometry measurements indicated that the axillary stratum corneum retained desquamated material on its surface more than on the forearm. This correlated with decreased levels of the desquamatory stratum corneum chymotryptic enzyme in the surface layers of the skin. These results indicate that the axilla has a distinct phenotype. Paper presented at the 22nd IFSCC Congress 2002, Edinburgh, Scotland [source] Progressive macular hypomelanosis in Singapore: a clinico-pathological studyINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 6 2006Sujith Prasad W. Kumarasinghe MBBS Introduction, Progressive macular hypomelanosis (PMH), a condition of uncertain etiology, is characterized by asymptomatic hypopigmented macules predominantly located on the trunk. To date, there are no reports from South-East Asia concerning this condition. We sought to record the clinical features of PMH in Asian patients, identify etiologic factors, and study the structural and ultrastructural features of melanocytes in this disorder. Methods, Patients who presented to the National Skin Center with acquired, hypopigmented macules on the trunk, without a history of inflammation or infection, were recruited. Erythrocyte sedimentation rate (ESR), complete blood count, fasting blood glucose, liver function tests, skin scrapings for fungi, and skin biopsy specimens (from lesional and normal skin) were obtained. Biopsies were stained with hematoxylin and eosin (H&E), Fontana Masson, an immunohistochemical panel for identification of melanocyte differentiation antibodies (HMB 45, Melan A, and S100) and CD 68. Electron microscopy (EM) was also performed. The patients were evaluated every 3 months. Results, During a 9 month period, eight patients (all Chinese) presented with hypopigmented, ill-defined, confluent macules involving the lower aspect of the trunk. There were four men and four women, and the mean age was 25.9 years (range 19,45 years). Skin scrapings were negative for fungi and laboratory tests were normal. Microscopic evaluation of skin biopsy speciments showed reduced pigmentation of lesional as compared with normal appearing skin, but H&E-stained sections revealed only minimal histologic differences between lesional and normal skin. EM demonstrated a statistically significant (P = 0.047, Wilcoxon Signed Rank Test, Wilcoxon 95% CI 0.02,0.62) higher ratio of stage IV and late stage III (dark) melanosomes in normal vs. lesional skin. Conclusions, PMH may occur among young adults in Singapore. Its etiology is uncertain. The melanin content of lesional skin appears to be less than that in normal sites. EM shows a higher ratio of immature melanosomes in lesional vs. normal skin. [source] Direct Dentin Bonding Technique Sensitivity When Using Air/Suction Drying StepsJOURNAL OF ESTHETIC AND RESTORATIVE DENTISTRY, Issue 2 2008PASCAL MAGNE DMD ABSTRACT Statement of Problem:, Moisture control before and after application of the primer/adhesive components of etch-and-rinse dentin bonding agents is usually achieved using a stream of air delivered by an air syringe. Suction drying with a suction tip is a common alternative for moisture control, but data about the use of suction drying instead of the air syringe is scarce or nonexistent. Purpose:, The purpose of this study was to compare the dentin microtensile bond strength (MTBS) using either the air syringe or the suction tip to control the amount of moisture. Materials and Methods:, Fifteen freshly extracted human molars were divided randomly into three groups of five. A three-step etch-and-rinse dentin bonding agent (OptiBond FL) was used. Group 1 was the control group and utilized air drying alone (with an air syringe) during the placement of the dentin adhesive on the ground-flat occlusal dentin surface. Group 2 also used air drying alone, but teeth were prepared with a standardized MOD cavity. Group 3 utilized suction drying alone in the standardized MOD cavity. All teeth were restored with 1.5-mm-thick horizontal increments of composite resin (Filtek Z100). Specimens were stored in water for 24 hours, then prepared for a nontrimming MTBS test. Bond strength data were analyzed with a Kruskal,Wallis test at p < 0.05. Specimens were also evaluated for mode of fracture and interface characterization using scanning electron microscope (SEM) analysis. Results:, The mean MTBSs were not statistically different from one another (p = 0.54) at 54.0 MPa (air-drying, flat dentin), 53.4 MPa (air-drying, MOD), and 49.2 MPa (suction drying, MOD). Microscopic evaluation of failure modes indicated that most failures were interfacial. Failed interfaces, when analyzed under SEM, appeared typically mixed with areas of failed adhesive resin and areas of cohesively failed dentin. Conclusions:, There are no differences in MTBS to human dentin using either the air syringe or the suction tip to control the amount of moisture. The conventional three-step dentin bonding agent used in the present study not only proved insensitive to the moisture-control method but also to the effect of increased polymerization shrinkage stress (ground-flat versus MOD preparation). CLINICAL SIGNIFICANCE Although the effect of common errors on the performance of total-etch adhesives has been investigated, data about the use of suction drying instead of an air syringe is scarce or nonexistent. The present study demonstrated that both the air syringe and the suction tip can be used to control moisture when using etch-and-rinse dentin bonding agents. The conventional three-step dentin bonding agent tested, OptiBond FL, demonstrated low technique sensitivity. [source] Fine-needle aspiration cytology in the follow-up of Hodgkin lymphomaDIAGNOSTIC CYTOPATHOLOGY, Issue 7 2008Pio Zeppa M.D. Abstract Hodgkin lymphoma (HL) is characterized by long survival and risk of relapse and second neoplasm. The aim of this study is to evaluate the possibility of improving the accuracy of fine-needle cytology (FNC) in HL follow-up using Power Doppler ultrasound (US) assistance and immediate microscopic evaluation (ICE). The study was performed in two consecutive groups of 200 FNC in HL patients. In the first group FNC of palpable lymph-nodes or extra lymph-nodal masses were performed without US assistance except for impalpable and/or deep located masses (nonassisted group); In the second group, all the FNC were performed under Power Doppler US assistance with ICE and immediately repeated in inadequate cases (assisted group). Cytological diagnoses were controlled by histology (61) or clinical follow-up (69); sensitivity and specificity were calculated in the two groups and to evaluate the effect of Power Doppler alone, adequate cases were compared with the total number of FNC in each of the two groups. FNC identified 90 negative cases, 3 false negatives, 70 HL relapse, 16 inadequate and 14 suspicious; second neoplasia were diagnosed in 12 cases and all histologically confirmed. Sensitivity and specificity were 64 and 84% in the nonassisted group and 86 and 94% in the assisted group and there were significant differences between the number of adequate cases v.s. the total number of FNC in each of the two groups. Sensitivity and specificity in assisted FNC are higher than in nonassisted ones. The main advantage of assisted FNC in the follow-up of HL is to produce accurate diagnoses avoiding invasive biopsies. Diagn. Cytopathol. 2008;36:467,472. © 2008 Wiley-Liss, Inc. [source] Surgical margin determination in head and neck oncology: Current clinical practice.HEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 11 2005Neck Society Member Survey, The results of an International American Head Abstract Background. Our aim was to investigate the ways in which surgeons who perform head and neck ablative procedures on a regular basis define margins, how they use frozen sections to evaluate margins, and the effect of chemoradiation on determining tumor margins. Methods. A custom-designed questionnaire was mailed to members of the American Head and Neck Society asking members how they evaluate and define tumor margins. Results. Of 1500 surveys mailed, 476 completed surveys were received. The most common response for distance of a clear pathologic margin was >5 mm on microscopic evaluation. A margin containing carcinoma in situ was considered a positive margin by most, but most did not consider a margin containing dysplasia a positive margin. When initial frozen section margins are positive for tumor and further resection results in negative frozen section margins, 90% consider the patient's margin negative. Most surgeons sample the frozen section from the surgical bed rather than from the main specimen. Nearly half use wider margins when resecting tumors treated with neoadjuvant therapy. When resecting recurrent or residual tumors treated with previous chemoradiation therapy, most resect to the pretreatment margin. Conclusions. No uniform criteria to define a clear surgical margin exist among practicing head and neck surgeons. Most head and neck surgeons consider margins clear if resection completed after an initial positive frozen section margin reveals negative margins, but this view is not shared by all. Most surgeons take frozen sections from the surgical bed; however, error may occur when identifying the positive margin within the surgical bed. The definition of a clear tumor margin after chemoradiation is unclear. These questions could be addressed in a multicenter prospective trial. © 2005 Wiley Periodicals, Inc. Head Neck27: XXX,XXX, 2005 [source] Activation of the cannabinoid 2 receptor (CB2) protects against experimental colitisINFLAMMATORY BOWEL DISEASES, Issue 11 2009Martin A. Storr MD Abstract Background: Activation of cannabinoid (CB)1 receptors results in attenuation of experimental colitis. Our aim was to examine the role of CB2 receptors in experimental colitis using agonists (JWH133, AM1241) and an antagonist (AM630) in trinitrobenzene sulfonic acid (TNBS)-induced colitis in wildtype and CB2 receptor-deficient (CB mice. Methods: Mice were treated with TNBS to induce colitis and then given intraperitoneal injections of the CB2 receptor agonists JWH133, AM1241, or the CB2 receptor antagonist AM630. Additionally, CB mice were treated with TNBS and injected with JWH133 or AM1241. Animals were examined 3 days after the induction of colitis. The colons were removed for macroscopic and microscopic evaluation, as well as the determination of myeloperoxidase activity. Quantitative reverse-transcriptase polymerase chain reaction (RT-PCR) for CB2 receptor was also performed in animals with TNBS and dextran sodium sulfate colitis. Results: Intracolonic installation of TNBS caused severe colitis. CB2 mRNA expression was significantly increased during the course of experimental colitis. Three-day treatment with JWH133 or AM1241 significantly reduced colitis; AM630 exacerbated colitis. The effect of JWH133 was abolished when animals were pretreated with AM630. Neither JWH133 nor AM1241 had effects in CB mice. Conclusions: We show that activation of the CB2 receptor protects against experimental colitis in mice. Increased expression of CB2 receptor mRNA and aggravation of colitis by AM630 suggests a role for this receptor in normally limiting the development of colitis. These results support the idea that the CB2 receptor may be a possible novel therapeutic target in inflammatory bowel disease. (Inflamm Bowel Dis 2009) [source] The cytotoxic effects of resin-based sealers on dental pulp stem cellsINTERNATIONAL ENDODONTIC JOURNAL, Issue 8 2010O. Trubiani Trubiani O, Caputi S, Di Iorio D, D'Amario M, Paludi M, Giancola R, Di Nardo Di Maio F, De Angelis F, D'Arcangelo C. The cytotoxic effects of resin-based sealers on dental pulp stem cells. International Endodontic Journal. Abstract Aim, To evaluate the effect of four current resin-based adhesives on expanded ex vivo human dental pulp mesenchymal stem cells (DP-MSCs). Methodology, Dental pulp mesenchymal stem cells were derived from dental pulps of ten donors. After in vitro isolation, dental pulp stem cells were analysed using flow cytometry. The immunophenotype of DP-MSCs disclosed the homogeneous expression of the mesenchymal-related antigens CD29, CD44, CD73, CD90, CD105, CD166. DP-MSCs were exposed to four different commercially available bonding systems (CMF Bond, Prime&Bond NT, Clearfil S3 Bond, XP Bond), and after 24, 48 and 72 h of incubation the morphological features and the cell growth were analysed. Moreover, the cell viability was evaluated at the same times by MTT assay. Data were statistically analysed using a two-way anova and Holm,Sidak method (, set at 0.05). Results, Significant differences were observed between the four groups when comparing DP-MSCs appearance. DP-MSCs survived and proliferated without inhibition in the presence of CMF Bond adhesive. On the contrary, microscopic evaluation of the other three groups revealed extensive cytotoxic effects from the dentine bonding agents. The MTT assay revealed no statistically significant differences in cell viability after 72 h between the control group and CMF Bond group. All the other experimental groups had statistically lower optical density values. Conclusions, CMF Bond adhesive allowed human dental pulp stem cells to survive and proliferate. All of the other dentine bonding agents had extensive cytotoxic effects. [source] Development of an ex vivo model for the study of microbial infection in human teethINTERNATIONAL ENDODONTIC JOURNAL, Issue 5 2007B. Patel Aims, (1) To infect human teeth artificially to mimic root canal and dentine infection, using the Constant Depth Film Fermenter (CDFF); (2) To verify the similarity of the infections to those found, in vivo, using culture and microscopy (SEM, LM and TEM). Methodology, Human teeth [n = 38 and n = 28, for phases I (preliminary) and II (definitive), respectively] were infected within the CDFF for a period of 28 days and at pre-selected time points were removed, externally decontaminated using validated protocols and subjected to either culture-dependent or microscopy protocols. The condition of the teeth was varied in phase I to establish the feasibility of the approach and identify optimal conditions. This informed the selection of optimal conditions for definitive test in phase II. For culture-dependent analysis in this phase, a dentine filing sample was obtained from the apical 5 mm of the root canal and cultured anaerobically to allow isolation of individual strains. Bacterial DNA was extracted from purified isolates, the 16S rRNA genes amplified by PCR and the amplicons sequenced for identity using sequence databases. Teeth assigned for microscopy were post-fixed in 3% gluteraldehyde after removal from the CDFF and then subjected to appropriate protocols prior to microscopic evaluation of the infection. Results, All three microscopy techniques and culture-dependent analysis confirmed infection of the human teeth using the CDFF, with root canal infections visually resembling closely those seen in vivo. Furthermore, partial 16S rRNA gene sequencing of DNA from cultured isolates confirmed a selective number of 7,9 genera/species in the apical portion of two teeth each at 7 and 28 days; these taxa are also commonly recovered from teeth with apical periodontitis, in vivo. There were no objective measures other than speciation and topographical evaluation to compare the artificial and real (in vivo) infections. Conclusions, The proposed ex vivo model has the potential for development into an investigative tool for studying the dynamics of bacterial ecology in infected root canals, both before and after treatment. Its advantage is the ability to control both the abiotic and biotic factors. There is a need for the development of objective measures to compare artificial and real bacterial biofilms. [source] Light and scanning electron microscopic evaluation of GlydeÔ File Prep in smear layer removalINTERNATIONAL ENDODONTIC JOURNAL, Issue 5 2003T. S. Lim Abstract Aim, To evaluate the effectiveness of GlydeÔ File Prep used in conjunction with sodium hypochlorite irrigation in the removal of smear layer produced during root canal instrumentation. Methodology, Thirty-nine extracted human teeth with single root canals were used. Access cavities were prepared and the teeth divided into three groups of 13 teeth each. Each group was treated by one of the three different regimes of irrigation and conditioning during root canal instrumentation. Group A: 0.5 mL of 1% NaOCl irrigation after each file size with an additional final irrigation of 10 mL 1% NaOCl; group B: 0.5 mL of 1% NaOCl irrigation after each file size with an additional final irrigation of 10 mL 17% EDTA; group C: GlydeÔ File Prep coated on each instrumentation file used in conjunction with 0.5 mL 1% NaOCl irrigation after each file size and an additional final irrigation of 10 mL 1% NaOCl. The teeth were then longitudinally grooved and sectioned. Root canal cleanliness was evaluated with the aid of a Nikon light microscope (×40 and ×100) and scanning electron microscope (×1000 and ×3000). The debris scores obtained at three canal regions were compared statistically within the same group and among different groups using repeated measurements of analysis of variance (anova) with Bonferroni adjustments and anova with posthoc Tukey HSD, respectively. Results, The canals treated with EDTA and GlydeÔ File Prep were significantly cleaner than those treated with NaOCl alone. The apical region of the root canals generally displayed more residual smear layer, but the difference was not significant. Conclusions, Used in conjunction with NaOCl irrigation, GlydeÔ File Prep was effective in removing smear layer produced during root canal instrumentation. [source] Effect of cell number on mesenchymal stem cell transplantation in a canine disc degeneration modelJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 10 2010Kenji Serigano Abstract Transplantation of mesenchymal stem cells (MSCs) inhibits the progression of disc degeneration in animal models. We know of no study to determine the optimal number of cells to transplant into the degenerated intervertebral disc (IVD). To determine the optimal donor cell number for maximum benefit, we conducted an in vivo study using a canine disc degeneration model. Autologous MSCs were transplanted into degenerative discs at 105, 106, or 107,cells per disc. The MSC-transplanted discs were evaluated for 12 weeks using plain radiography, magnetic resonance imaging, and gross and microscopic evaluation. Preservation of the disc height, annular structure was seen in MSC-transplantation groups compared to the operated control group with no MSC transplantation. Result of the number of remaining transplanted MSCs, the survival rate of NP cells, and apoptosis of NP cells in transplanted discs showed both structural microenvironment and abundant extracellular matrix maintained in 106 MSCs transplanted disc, while less viable cells were detected in 105 MSCs transplanted and more apoptotic cells in 107 MSCs transplanted discs. The results of this study demonstrate that the number of cells transplanted affects the regenerative capability of MSC transplants in experimentally induced degenerating canine discs. It is suggested that maintenance of extracellular matrix by its production from transplanted cells and/or resident cells is important for checking the progression of structural disruption that leads to disc degeneration. Published by Wiley Periodicals, Inc. J Orthop Res 28:1267,1275, 2010 [source] Toxic effect of environmental acid-stress on the sperm of a hill-stream fish Devario aequipinnatus: A scanning electron microscopic evaluationMICROSCOPY RESEARCH AND TECHNIQUE, Issue 2 2009Sudip Dey Abstract Environmental stress due to acidic pH of water was found to be one of the major factors leading to toxic effects on the sperm of a hill-stream fish Devario aequipinnatus of Meghalaya, India. The Scanning Electron Microscopy of the transverse section of testes of the fish collected from its natural habitat with acidic pH (5.6,6.0) showed that the sperms were clumped together and their tails were either absent or were of extremely small length. The acrosome and midpiece were also not well differentiated. When the fingerlings from the natural habitat were reared to maturity in aquarium with water from natural habitat after changing the pH to alkaline range (8.0,8.2), the clumping of the sperm was not observed. The sperm tail was found to be well-developed along with well-differentiated acrosome and midpiece. Since the only change in the water quality parameters of the experimental aquarium as compared to those of the natural habitat was the pH, it is evident that the abnormal features of the sperm observed in fish from natural habitat is mainly because of environmental acid stress. Microsc. Res. Tech., 2009. © 2008 Wiley-Liss, Inc. [source] Mucin Coatings Suppress Neutrophil Adhesion to a Polymeric Model BiomaterialMICROSCOPY RESEARCH AND TECHNIQUE, Issue 10 2007Tomas Sandberg Abstract Following our recent study on the fractionation, characterization, and model adsorption of mucins derived from bovine salivary glands (BSM), porcine stomach scrapings (PGM), and human whole saliva (MG1), we here present a microscopic evaluation of the interactions between mucin-coated substrates and human neutrophils. Our results show that surface-coating with BSM, PGM, and MG1 can be effectively used to suppress the adhesion of neutrophils to a polymeric model biomaterial (Thermanox). Neutrophil morphologies found on Thermanox substrates coated with mucins resemble those observed for nonactivated neutrophils found in circulation. Notably, low neutrophil adhesion can be obtained at a significantly lower coating concentration (0.125 mg/mL) for the compositionally complex MG1 mucin than for the relatively pure BSM and PGM mucins (1 mg/mL). Furthermore, since coating at a low BSM and PGM concentration (0.25 mg/mL) results in higher cell counts and more spread cells than in the high-concentration case, we suggest that dense mucin surface packing is critical for good coating performance. In conclusion, the present study demonstrates how mucins from three different sources, of different compositional and structural status, efficiently can be used to suppress neutrophil adhesion and activation. This finding makes them potent candidates for use as biomaterial coatings. Microsc. Res. Tech., 2007. © 2007 Wiley-Liss, Inc. [source] Nerve regeneration through an epineurial sheath: Its functional aspect compared with nerve and vein graftsMICROSURGERY, Issue 5 2001Ercan Karacao, lu M.D. Although nerve graft is still the only reliable choice in repair of defects in peripheral nerve structure, it has the disadvantage of donor nerve morbidity and of sometimes being unavailable. It has long been researched in alternate nerve grafts with other materials. Studies have shown that nerves could regenerate across short nerve gaps through various conduits, such as veins, pseudosheaths, and bioabsorbable tubes. Despite encouraging studies, their functional results remain unclear. The present study used 40 rats, in which nerve grafts, vein grafts, and epineurial tubes were placed into 1-cm gaps in sciatic nerves created by resection. In one group, sciatic nerves were denuded of the surrounding epineurium, to assess the possible morbidity caused by epineurial sheath technique. At 2, 4, 8, 12, 20, and 28 weeks, functional assessment of nerve regeneration was performed using walking track analysis. The number of myelinated fibers and fiber diameters was measured and electron microscopic evaluation performed. Functionally, the index values were very close to each other in nerve graft and epineurial sheath groups. Morphometric analysis showed significance between the groups. The result of denuded sciatic nerve group was the same as the base track values. It was concluded that the ready availability of epineurial sheath as a conduit to span short nerve gaps could eliminate the morbidity associated with nerve graft harvest and capitalize on the potential benefits of neurotrophism in directing nerve regeneration. © 2001 Wiley-Liss, Inc. Microsurgery 21:196,201 2001 [source] Intra-arterial Effects of Cisplatin on Microvascular Anastomoses in the Rat ModelTHE LARYNGOSCOPE, Issue 8 2002Deepak Gurushanthaiah MD Abstract Objective To evaluate the patency of microvascular anastomoses in arteries exposed to intra-arterial cisplatin. Study Design Animal model. Methods The common iliac artery of 15 rats was injected with 150 mg/m2 cisplatin. Five rats were injected with the same volume of saline serving as physiological controls. The ipsilateral femoral artery was transected and anastomosed using microsurgical technique within 3 to 5 days. A Doppler probe was used before and after the anastomosis to assess blood flow. The vessel was re-examined on postoperative day 5. Pulsatile blood flow and the presence or absence of a Doppler signal was recorded at this time. Vessels were harvested to include the anastomosis site and fixed for histological evaluation. The contralateral femoral artery was also harvested for comparison. Results All femoral artery anastomoses in the experimental and control arm had good, pulsatile blood flow by microscopic evaluation. No thrombosed vessels were visualized, and Doppler signals remained strong at all vessel anastomoses. Histological analysis of the vessels revealed a trend toward increased inflammatory infiltrate in the walls of the vessels treated with cisplatin. We did not appreciate a functional decrease in lumen size. Conclusions Selective catheterization intra-arterial cisplatin chemotherapy does not affect the patency of vessels following a microvascular anastomosis in the rat model. The trend toward increased inflammatory response in the vessel walls may suggest the need for closer monitoring in patients treated with intra-arterial chemotherapy. [source] Investigational New Drug-Directed Toxicology and Pharmacokinetic Study of 4-[3-(2-Nitro-1-Imidazolyl)-Propylamino]-7-Chloroquinoline Hydrochloride (NLCQ-1, NSC 709257) in Beagle DogsBASIC AND CLINICAL PHARMACOLOGY & TOXICOLOGY, Issue 6 2010Maria V. Papadopoulou The present study is one of several pre-clinical toxicology studies conducted in support of an ,investigational new drug' (IND) application to test this agent as an adjuvant to radio/chemotherapy for the treatment of cancer in humans. Twenty-four dogs were each assigned to one vehicle control group or to one of three test article-treated groups (three dogs/sex/treatment group). Intravenous (i.v.) doses of 0, 2.74, 5.48 and 10.95 mg/kg/day (54.8, 109.6 or 219 mg/m2/day) were administered on a per day × 5 days (qd × 5) schedule. NLCQ-1 was formulated as a solution in sterile saline at 1.5 mg/ml. None of the dogs died during this 33-day study. With few exceptions, most of the clinical signs of toxicity were noted within 2 hr following dosing in the 10.95 mg/kg/day dose group. These observations included aggressive behaviour, ataxia, tachypnea, emesis, hypoactivity, excessive salivation, tremors, and involuntary urination and defecation. Aggressive behaviour was judged to be dose-limiting. No clinical signs of toxicity were noted during the 28-day observation period that followed the 5-day dose period. Findings in a functional observation battery examination were consistent with the clinical observations. No drug-related effects were noted on the body weight or food consumption values, and no drug-related changes were noted during ocular examinations made on these animals prior to scheduled necropsy or during examination of electrocardiogram recordings made at 15 min. and 2 hr after dosing on days 1 and 5. No definitive changes in haematology, clinical chemistry or coagulation values were noted in dogs treated with NLCQ-1. NLCQ-1 was detected in the plasma of treated dogs on days 1 and 5, up to 60 min. after dosing (2.74 and 5.48 mg/kg/day) and up to 8 hr after dosing (10.95 mg/kg/day). There was a dose-related increase in maximum plasma concentration of NLCQ-1 at 5 min. after dosing; comparable concentrations were noted on days 1 and 5. No definitive test article-related lesions were noted during microscopic evaluation of tissues from dogs in this study, although lesions noted at the injection site and in the vascular tissue, lungs, thymus, prostate gland, muscle, adrenal cortex and tongue may have resulted from treatment with this drug. Any drug-related toxicity noted was readily reversible and not cumulative. No sex difference was detected in the susceptibility to NLCQ-1-induced toxicity. [source] In vivo confocal microscopic evaluation of inflammatory changes in the ocular surfaceACTA OPHTHALMOLOGICA, Issue 2009A LABBE Purpose The ocular surface constitutes a complex physiopathological and anatomical entity assuring the barrier between the outside world and the fragile ocular structures. Ophthalmic instruments such as the slit lamp, which magnifies approximately 40 times, cannot provide details of the corneal structures at the cellular level. Methods In vivo confocal microscopy using the HRT Rostock Cornea module® (HRT / RCM) provides better resolution and therefore outlines distinctively in vivo inflammatory changes occurring in the ocular surface. Results In vivo confocal microscopy is capable of providing corneal, conjunctival and limbal cellular details in different ocular surface diseases such as dry eye, infectious keratitis, toxic keratitis, corneal intraepithelial neoplasia or vernal keratoconjunctivitis. Conclusion In correlation with ex vivo impression cytology analysis, in vivo confocal microscopy constitutes an interesting aid in the diagnosis and management of complex ocular surface conditions. [source] Corneal injury by formic acid: one-year clinical course and in-vivo confocal microscopic evaluationCLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 7 2008Neil Lagali PhD No abstract is available for this article. [source] Effects of 17 ,-estradiol exposure on Xenopus laevis gonadal histopathologyENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 5 2010Jeffrey C. Wolf Abstract The natural estrogen 17 ,-estradiol (E2) is a potential environmental contaminant commonly employed as a positive control substance in bioassays involving estrogenic effects. The aquatic anuran Xenopus laevis is a frequent subject of reproductive endocrine disruptor research; however, histopathological investigations have tended to be less than comprehensive. Consequently, a study was designed to characterize gross and microscopic changes in the gonads of X. laevis as a result of E2 exposure. Additional goals of this study, which consisted of three separate experiments, included the standardization of diagnostic terminology and criteria, the validation of statistical methodology, and the establishment of a half maximal effective concentration (EC50) for E2 as defined by an approximately 50% conversion of presumptive genotypic males to phenotypic females. In the first experiment, frogs were exposed to nominal concentrations of 0, 0.2, 1.5, or 6.0,µg/L E2. From these experimental results and those of a subsequent range finding trial, the EC50 for E2 was determined to be approximately 0.2,µg/L. This E2 concentration was utilized in the other two experiments, which were performed at different facilities to confirm the reproducibility of results. Experiments were conducted according to Good Laboratory Practice guidelines, and the histopathologic evaluations were peer reviewed by an independent pathologist. Among the three trials, the histopathological findings that were strongly associated with E2-exposure (p,<,0.001 to 0.0001) included an increase in the proportion of phenotypic females, mixed sex, dilated testis tubules, dividing gonocytes in the testis, and dilated ovarian cavities in phenotypic ovaries. A comparison of the gross and microscopic evaluations suggested that some morphologic changes in the gonads may potentially be missed if studies rely entirely on macroscopic assessment. Environ. Toxicol. Chem. 2010;29:1091,1105. © 2010 SETAC [source] | |||||||||||||