Scanning electron microscopy as an auxiliary method in the study of exhumed bones

Scanning electronmicroscopy (SEM) has been used in forensic science in many ways. The reports of cases in which SEM has been used as an auxiliary method in the investigation of exhumed bones are rare. In this article, we report an exhumation that was made to determine if a seized weapon could have been used in a homicide. We used SEM to analyze a fracture in the interior of the skull of the victim. The findings described in this article showed us that it is possible to develop new researches in this field. (C) 2010 Elsevier Ireland Ltd. All rights reserved.

Comparison of the GDx VCC scanning laser polarimeter and the stratus optical coherence tomograph in the detection of band atrophy of the optic nerve

Aim To compare the ability of scanning laser polarimeter (SLP) with variable corneal compensation (GDx VCC) and optical coherence tomograph (Stratus OCT) to discriminate between eyes with band atrophy (BA) of the optic nerve and healthy eyes. Methods The study included 37 eyes with BA and temporal visual field (VF) defects from chiasmal compression, and 29 normal eyes. Subjects underwent standard automated perimetry (SAP) and retinal nerve fibre layer (RNFL) scans using GDx VCC and Stratus OCT. The severity of the VF defects was evaluated by the temporal mean defect (TMD), calculated as the average of 22 values of the temporal total deviation plot on SAP. Receiver operating characteristic (ROC) curves were calculated. Pearson`s correlation coefficients were used to evaluate the relationship between RNFL thickness parameters and the TMD. Results No significant difference was found between the ROC curves areas (AUCs) for the GDx VCC and Stratus OCT with regard to average RNFL thickness (0.98 and 0.99, respectively) and the superior (0.94; 0.95), inferior (0.96; 0.97), and nasal (0.92; 0.96) quadrants. However, the AUC in the temporal quadrant (0.77) was significantly smaller (P < 0.001) with GDx VCC than with Stratus OCT (0.98). Lower TMD values were associated with smaller RNFL thickness in most parameters from both equipments. Conclusion Adding VCC resulted in improved performance in SLP when evaluating eyes with BA, and both technologies are sensitive in detecting average, superior, inferior, and nasal quadrant RNFL loss. However, GDx VCC still poorly discriminates RNFL loss in the temporal quadrant when compared with Stratus OCT.

Comparison of Different Spectral Domain Optical Coherence Tomography Scanning Areas for Glaucoma Diagnosis

Purpose: To evaluate retinal nerve fiber layer (RNFL), optic nerve head (ONH), and macular thickness measurements for glaucoma detection using the RTVue spectral domain optical coherence tomograph. Design: Diagnostic, case-control study. Participants: One hundred forty eyes of 106 glaucoma patients and 74 eyes of 40 healthy subjects from the Diagnostic Innovations in Glaucoma Study (DIGS). Methods: All patients underwent ocular imaging with the commercially available RTVue. Optic nerve head, RNFL thickness, and macular thickness scans were obtained during the same visit. Receiver operating characteristic (ROC) curves and sensitivities at fixed specificities (80% and 95%) were calculated for each parameter. Main Outcome Measures: Areas under the ROC curves (AUC) and sensitivities at fixed specificities of 80% and 95%. Results: The AUC for the RNFL parameter with best performance, inferior quadrant thickness, was significantly higher than that of the best-performing ONH parameter, inferior rim area (0.884 vs 0.812, respectively; P = 0.04). There was no difference between ROC curve areas of the best RNFL thickness parameters and the best inner macular thickness measurement, ganglion cell complex root mean square (ROC curve area = 0.870). Conclusions: The RTVue RNFL and inner retinal macular thickness measurements had good ability to detect eyes with glaucomatous visual field loss and performed significantly better than ONH parameters.

Scanning laser polarimetry with enhanced corneal compensation for detection of axonal loss in band atrophy of the optic nerve

PURPOSE: To compare the abilities of scanning laser polarimetry (SLP) with enhanced corneal compensation (ECC) and variable corneal compensation (VCC) modes for detection of retinal nerve fiber layer (RNFL) loss in eyes with band atrophy (BA) of the optic nerve. DESIGN. Cross-sectional study. METHODS: Thirty-seven eyes from 37 patients with BA and temporal visual field defect from chiasmal compression and 40 eyes from 40 healthy subjects were studied. Subjects underwent standard automated perimetry and RNFL measurements using an SLP device equipped with VCC and ECC. Receiver operating characteristic (ROC) curves were calculated for each parameter. Pearson correlation coefficients were obtained to evaluate the relationship between RNFL thickness parameters and severity of visual field loss, as assessed by the temporal mean defect. RESULTS: All RNFL thickness parameters were significantly lower in eyes with BA compared with normal eyes with both compensation modes. However, no statistically significant differences were observed in the areas under the ROC curves for the different parameters between GDx VCC and ECC (Carl Zeiss Meditec, Inc, Dublin, California, USA). Structure-function relationships also were similar for both compensation modes. CONCLUSIONS: No significant differences were found between the diagnostic accuracy of GDx ECC and that of VCC for detection of BA of the optic nerve. The use of GDx ECC does not seem to provide a better evaluation of RNFL loss on the temporal and nasal sectors of the peripapillary retina in subjects with BA of the optic nerve.

Insights on calcium-independent phospholipid membrane damage by Lys49-PLA(2) using tryptophan scanning mutagenesis of bothropstoxin-I from Bothrops jararacussu

Bothropstoxin-I (BthTx-I) is a homodimerie Lys49-PLA(2) from the venom of the snake Bothrops jararacussu, which lacks hydrolytic activity against phospholipid substrates, yet permeabilizes membranes by a Ca2+- independent mechanism. The interaction of the BthTx-I with model membranes has been studied by intrinsic tryptophan fluorescence emission (ITFE) spectroscopy. Nine separate mutants have been created each with a unique tryptophan residue located at a different position in the interfacial recognition site (IRS) of the protein. The rapid and efficient Ca2+-independent membrane damage against unilamellar liposomes composed of DPPC/DMPA in a 9:1 molar ratio was unaffected by these substitutions. Binding studies revealed low protein affinity for these liposomes and no changes were observed in the ITFE properties. In contrast, the binding of all mutants to DPPC/DMPA liposomes in a 1:1 molar ratio was stronger, and was correlated with altered ITFE properties. The blue-shifted emission spectra and increased emission intensity of mutants at positions 31, 67 and 115-117 in the interface recognition surface of the protein suggest these regions are partially inserted into the membrane. These results are consistent with a model for the Ca2+-independent membrane damaging mechanism that involves a transient interaction of the protein with the outer phospholipid leaflet of the target membrane. (C) 2007 Elsevier Masson SAS. All rights reserved.

Characteristics of Filiform, Fungiform and Vallate Papillae and Surface of Interface Epithelium-Connective Tissue of the Maned Sloth Tongue Mucosa (Bradypus torquatus, Iliger, 1811): Light and Scanning Electron Microscopy Study

The study of lingual surfaces and the surface of interface epithelium-connective tissue of the tongue of Bradypus torquatus was performed by employing the light and scanning electron microscopy (SEM) techniques. The results revealed that the rostral part of the tongue presents a round apex and covered by filiform and fungiform lingual papillae and a ventral smooth surface. It was observed that the epithelial layer of the dorsal surface possesses the basal, spinosum, granular and cornified epithelial cells. The lamina propria is characterized by a dense connective tissue forming the long, short and round papillae. Numerous typical filiform papillae are located especially in the rostral part intermingled for few fungiform papillae, which were revealed in three-dimensional SEM images. Usually, the fungiform papillae are located in the border of rostral apex of the tongue exhibiting the rounded form. They are covered by keratinized epithelial cells. In the fungiform papillae, several taste pores were observed on the surface. The vallate papillae presented numerous taste buds in the wall of epithelial cells, being that the major number of taste buds is located on the superior half of vallate papilla. The taste pores are surrounded by several laminae of keratinized epithelial cells. The samples treated with NaOH solution and examined by SEM revealed, after removal of the epithelial layer, the dense connective core in original disposition, presenting different sizes and shapes. The specimens stained with Picrosirius and examined by polarized light microscopy revealed the connective tissue, indicating the collagen fibres type I and type III.

Three-dimensional Characteristics of the Interface Epithelium-Connective Tissue Surface of Finger`s Lamina Propria of Cebus apella Monkey: Scanning Electron Microscopy Study

In the present paper were analysed the three-dimensional characteristics of the interface epithelium-connective tissue surface of finger prints of Cebus apella monkey employing the scanning electron microscopic methods. The connective tissue core (CTC) and epithelial papillae were examined verifying the three-dimensional configuration of the tissue projections. The samples were fixed in Bouin solsution for histologic preparations and in modified Karnovsky for examine to observe in scanning electron microscopy. After treatment in the 10% NaOH solution during 3 to 5 days, the surface of finger prints revealed a distribution of CTC of lamina propria in situ showing original three-dimensional SEM images. The linear and circular dispositions CTC, and the furrows were clearly identified. Each pointed papilla presented a large base and longitudinal disposition of thick collagen fiber bundles and in some areas with a complex reticular formations. The longitudinal furrows between the pointed papillae exhibited a dense layer of connective tissue and showed only low CTC or laminar in shape. The presence of numerous foramina of sweat gland were noted in three-dimensional SEM images.

Light and scanning electron microcopy study of the tongue in Rhea americana

Morphological characteristics of the tongue were studied in adult rhea (Rhea americana). The lingual surface and the surface of epithelium-connective tissue interface of rhea tongue were examined macroscopically and by light and scanning electron microscopy. The rhea tongue revealed a triangular aspect, without adjustment of the inferior bill formation, occupying approximately of the length of the oral cavity. Lingual papilla-like structures were not observed over the lingual surface. The tongue mucosa was composed of a thick non-keratinized stratified squamous epithelium in the dorsal and ventral part, supported by a connective tissue core. The submucosa contained numerous glands with cytoplasmic granules, and luminal secretion was positive for histochemical reaction to Alcian Blue in pH 2.5 and PAS, and negative to Alcian Blue in pH 0.5. Despite the rudimentary characteristic of the tongue in rhea, our results suggest an important role of tongue secretions in food lubrication and humidification during the swallowing process, based on the enormous quantity of lingual glands in the submucosa and the histochemical characteristics of their secretions.

Redescription of Amblyomma varium Koch, 1844 (Acari : Ixodidae) based on light and scanning electron microscopy

Amblyomma varium Koch, 1844 is a Neotropical tick, known as the `sloth`s giant tick`, with records from southern Central America to Argentina. It is found almost exclusively on mammals of the families Bradypodidae and Magalonychidae (Xenarthra). Differences exist in discussions with regard to the dentition of the female hypostome being either 3/3 or 4/4. The male was also originally described as having a short spur on coxa IV, but some specimens recently collected from different Brazilian localities have this spur three times longer. These differences beg the question of whether there is more than one species included under this taxon. In order to answer this question and to clarify the taxonomic characters of this species, 258 adult specimens were examined, and a redescription of male and female based on light and scanning electron microscopy is provided. In addition, DNA was extracted from males with either a long or a short spur on coxa IV to help settle this question for future investigations on their taxonomy. The morphological study showed that the dental formula pattern for males and females is 3/3 and 4/4, respectively. When sequenced, the 12 S rDNA genes of both A. varium males with long and short spurs on coxa IV were found to be identical, indicating that the length of the spurs on coxa IV is likely to be an intraspecifically polymorphic character of this species.

Micromorphology of Resin-Dentin Interfaces Using One-Bottle Etch&Rinse and Self-Etching Adhesive Systems on Laser-Treated Dentin Surfaces: A Confocal Laser Scanning Microscope Analysis

Background and Objectives: This study evaluated the hybrid layer (HL) morphology created by three adhesive systems (AS) on dentin surfaces treated with Er:YAG laser using two irradiation parameters. Study Design: Occlusal flat dentin surfaces of 36 human third molars were assigned into nine groups (n = 4) according to the following ASs: one bottle etch&rinse Single Bond Plus (3M ESPE), two-step Clearfil Protect Bond (Kuraray), and all-in-one S3 Bond (Kuraray) self-etching, which were labeled with rhodamine B or fluorescein isothiocyanate dextran and were applied to dentin surfaces that were irradiated with Er:YAG laser at either 120 (38.7 J/cm(2)) or 200 mJ/pulse (64.5 J/cm(2)), or were applied to untreated dentin surfaces (control group). The ASs were light-activated following MI and the bonded surfaces were restored with resin composite Z250 (3M ESPE). After 24 hours of storage in vegetable oil, the restored teeth were vertically, serially sectioned into 1-mm thick slabs, which had the adhesive interfaces analyzed with confocal laser microscope (CLSM-LSM 510 Meta). CLSM images were recorded in the fluorescent mode from three different regions along each bonded interface. Results: Non-uniform HL was created on laser-irradiated dentin surfaces regardless of laser irradiation protocol for all AS, while regular and uniform HL was observed in the control groups. ""Stretch mark""-like red lines were found within the HL as a result of resin infiltration into dentin microfissures, which were predominantly observed in 200 mJ/pulse groups regardless of AS. Poor resin infiltration into peritubular dentin was observed in most regions of adhesive interfaces created by all ASs on laser-irradiated dentin, resulting in thin resin tags with neither funnel-shaped morphology nor lateral resin projections. Conclusion: Laser irradiation of dentin surfaces at 120 or 200 mJ/pulse resulted in morphological changes in HL and resin tags for all ASs evaluated in the study. Lasers Surg. Med. 42:662-670, 2010. (C) 2010 Wiley-Liss, Inc.

Comparative analysis of root surface smear layer removal by different etching modalities or erbium:yttrium-aluminum-garnet laser irradiation. A scanning electron microscopy study

The purpose of this study was to evaluate the effect of erbium:yttrium-aluminum-garnet (Er:YAG) laser (2.94 mu m) irradiation on the removal of root surface smear layer of extracted human teeth and to compare its efficacy with that of citric acid, ethylenediamine tetra-acetic acid (EDTA), or a gel containing a mixture of tetracycline hydrochloride (HCl) and citric acid, using scanning electron microscopy (SEM). Thirty human dentin specimens were randomly divided into six groups: G1 (control group), irrigated with 10 ml of physiologic saline solution; G2, conditioned with 24% citric acid gel; G3, conditioned with 24% EDTA gel; G4, conditioned with a 50% citric acid and tetracycline gel; G5, irradiated with Er:YAG laser (47 mJ/10 Hz/5.8 J/cm(2)/pulse); G6, irradiated with Er:YAG laser (83 mJ/10 Hz/10.3 J/cm(2)/pulse). Electron micrographs were obtained and analyzed according to a rating system. Statistical analysis was conducted with Kruskal-Wallis and Mann-Whitney tests (P < 0.05). G1 was statistically different from all the other groups; no statistically significant differences were observed between the Er:YAG laser groups and those undergoing the other treatment modalities. When the two Er:YAG laser groups were compared, the fluency of G6 was statistically more effective in smear layer removal than the one used in G5 (Mann-Whitney test, P < 0.01). Root surfaces irradiated by Er:YAG laser had more irregular contours than those treated by chemical agents. It can be concluded that all treatment modalities were effective in smear layer removal. The results of our study suggest that the Er:YAG laser can be safely used to condition diseased root surfaces effectively. Furthermore, the effect of Er:YAG laser irradiation on root surfaces should be evaluated in vivo so that its potential to enhance the healing of periodontal tissues can be assessed.

Morphological analysis of human and bovine dentine by scanning electron microscope investigation

Objective: The objective of this study was to compare the superficial morphology of bovine and human sclerotic dentine. Design: For the morphological analysis, bovine (n = 3) and human (n = 3) incisors exhibiting exposed dentine were used. Dentine presented characteristics of sclerosis: brownish, smooth and shiny-the vitreous appearance. The teeth were prepared for assessment on a scanning electron microscope (SEM). Three pre-determined areas of each sample were submitted to SEM. The number of open tubules per area was obtained from the electron micrographs (n = 9 per group) for comparison purposes. Results: The number of open tubules in both species compared were similar (p > 0.05). Human dentine presented 31.89 +/- 23.94 open tubules per area, whereas bovine dentine showed 30.33 +/- 18.14 open tubules per area. Conclusion: Based on the results, we concluded that dentine exposed at the incisal surface of human and bovine teeth presented similar clinical and micro-morphological aspects, represented by surfaces with equivalent numbers of open dentinal tubules. (C) 2007 Elsevier Ltd. All rights reserved.

Scanning Electron Microscopy In Vitro Study on the Effect of Carisolv Application on Periodontally Diseased Root Surfaces

The purpose of this study was to evaluate the characteristics of diseased root surfaces treated by the association of scaling and the application of Carisolv. Twenty-four uniradicular periodontally involved teeth were used in this study The teeth were divided randomly into three groups: eight teeth were scaled and root planed until there was a complete visible removal of calculus (group 1), Carisolv was applied on the root surfaces of eight teeth twice for 30 seconds before scaling with a sharp curette (group 2), and eight teeth received the same treatment as in group 2 but with a blunt curette (group 3). Specimens were examined using scanning electron microscopy The superficial aspect of the roots from group 1 presented scratches that mirrored the curette cutting edge, and the smear layer completely covered the surface. Root surfaces from groups 2 and 3 also presented a smear layer that covered the surface completely but it was somewhat smoother than group 1. The use of Carisolv as an adjunct to scaling and root planing presented no advantage for smear layer removal over scaling alone, suggesting that no benefit is obtained by the use of Carisolv during periodontal mechanical treatment. (Int J Periodontics Restorative Dent 2011;31:91-95.)

Effects of Ultramorphological Changes on Adhesion to Lased Dentin-Scanning Electron Microscopy and Transmission Electron Microscopy Analysis

Dentin irradiation with erbium lasers has been reported to alter the composite resin bond to this treated surface. There is still a lack of studies reporting the effect of erbium lasers on dentin organic content and elucidating how laser treatment could interfere in the quality of the resin-dentin interface. This study aimed to evaluate the effect of erbium laser irradiation on dentin morphology and microtensile bond strength (lTBS) of an adhesive to dentin. Seventy-two dentin disks were divided into nine groups (n = 8): G1-Control (600-grit SiC paper); Er:YAG groups: G2-250 mJ/4 Hz; G3-200 mJ/4 Hz; G4-180 mJ/10 Hz; G5-160 mJ/10 Hz; Er, Cr:YSGG groups: G6-2 W/20 Hz; G7-2.5 W/20 Hz; G8-3 W/20 Hz; G9-4 W/20 Hz. Specimens were processed for cross-sectional analysis by scanning electron microscopy (SEM) (n = 3), transmission electron microscopy (TEM) (n = 2), and adhesive interface (n = 3). Forty-five dentin samples (n = 5) were restored and submitted to lTBS testing. ANOVA (alpha = 5%) revealed that G1 presented the highest lTBS values and irradiated groups did not differ from each other. TEM micrographs showed a superficial layer of denatured collagen fibrils. For SEM micrographs, it was possible to verify the laser effects extending to dentin subsurface presenting a rough aspect. Cross-sectional dentin micrographs of this hybridized surface revealed a pattern of modified tags with ringlike structures around it. This in vitro study showed that erbium laser irradiation interacts with the dental hard tissue resulting in a specific morphological pattern of dentin and collagen fibrils that negatively affected the bond strength to composite resin. Microsc. Res. Tech. 74:720-726, 2011. (C) 2010 Wiley-Liss, Inc.