Ellagic acid on the quality of the adhesive interface of class I composite resin restorations after aging

To evaluate the effect of ellagic acid on the inhibition of matrix metalloproteinase by analyzing the quality of the adhesive interface with bond strength measures in periods of 24 hours and six months of storage. Method: 40 healthy human third molars were prepared with class I cavities (5x4x3mm). The teeth were divided into four experimental groups: Group 1- without application of ellagic acid and storage time of 24 hours; Group 2- with ellagic acid/24 hours; G3- without ellagic acid/six months; Group 4- with ellagic acid/six months. Then, the cavities were restored with Single Bond Universal adhesive and Z350 composite resin, with and without the previous application of ellagic acid. Subsequently, hourglass-shaped specimens were obtained and subjected to the bond strength (BS) test (n = 10) in a universal testing machine. The bond test was performed after 24 hours and six months of storage. For the standard evaluation (n = 3) the samples were infiltrated with silver nitrate and placed in a developing solution for analysis in a Scanning Electron Microscope (SEM). The data obtained were analyzed with the Kruskal-Wallis non-parametric test, showing a statistically significant difference. Results: The highest bond strength values were found for the 24-hour groups followed by the groups with six months of storage. For nano-infiltration, groups G1 and G2 showed lower infiltration than groups G3 and G4. Conclusion: The previous application of ellagic acid did not affect the BS of the adhesive interface of the adhesive system analyzed, regardless of storage time.

Specification of Bacteriophage Isolated Against Clinical Methicillin-Resistant Staphylococcus Aureus

OBJECTIVES: The emergence of resistant bacteria is being increasingly reported around the world, potentially threatening millions of lives. Amongst resistant bacteria, methicillin-resistant Staphylococcus aureus (MRSA) is the most challenging to treat. This is due to emergent MRSA strains and less effective traditional antibiotic therapies to Staphylococcal infections. The use of bacteriophages (phages) against MRSA is a new, potential alternate therapy. In this study, morphology, genetic and protein structure of lytic phages against MRSA have been analysed. METHODS: Isolation of livestock and sewage bacteriophages were performed using 0.4 μm membrane filters. Plaque assays were used to determine phage quantification by double layer agar method. Pure plaques were then amplified for further characterization. Sulfate-polyacrylamide gel electrophoresis and random amplification of polymorphic DNA were run for protein evaluation, and genotyping respectively. Transmission electron microscope was also used to detect the structure and taxonomic classification of phage visually. RESULTS: Head and tail morphology of bacteriophages against MRSA were identified by transmission electron microscopy and assigned to the Siphoviridae family and the Caudovirales order. CONCLUSION: Bacteriophages are the most abundant microorganism on Earth and coexist with the bacterial population. They can destroy bacterial cells successfully and effectively. They cannot enter mammalian cells which saves the eukaryotic cells from lytic phage activity. In conclusion, phage therapy may have many potential applications in microbiology and human medicine with no side effect on eukaryotic cells.

Scanning electron microscopy of superficial white onychomycosis

AbstractSuperficial white onychomycosis is characterized by opaque, friable, whitish superficial spots on the nail plate. We examined an affected halux nail of a 20-year-old male patient with scanning electron microscopy. The mycological examination isolated Trichophyton mentagrophytes. Abundant hyphae with the formation of arthrospores were found on the nail's surface, forming small fungal colonies. These findings showed the great capacity for dissemination of this form of onychomycosis.

Pathological morphological characteristics of experimental rats with acute light and heavy pancreatitis / 重庆医学

Objective The aim of this study is to demonstrate the pathological characteristics about two types of pancreati‐tis ,providing new thinking about the mechanism of severe acute pancreatitis .Methods Thirty male Sprague‐Dawley rats were ran‐domly divided into three equal groups :sham‐operated (SO ,n=10) group ,mild acute pancreatitis (MAP ,n=10)) group and severe acute pancreatitis (SAP ,n=10) group ,all the rats were killed after 12 h of building model .Under the microscope ,we detected the pathological changes of pancreas ,liver ,lung and small intestine .The ultrastructure of pancreas ,liver ,lung and small intestine tissue were observed by transmission electron microscope .Results In SAP group ,congestion ,edema ,inflammatory cell infiltration ,lea‐king of blood componedts ,vascular endothelial injury and thrombosis of microcirculation were obviously observed .There is no ap‐parent pathological changes in the MAP group except the edema of pancreas .Conclusion Hemorrhage and necrosis are the main pathological characteristics in SAP rats ,has essential difference with MAP .These pathological characteristics provides us a new thinking for further study about the mechanism of SAP .

Scanning electron microscopy of acantholysis in pemphigus foliaceus / Microscopia eletrônica de varredura da acantólise no pênfigo foliáceo

We performed scanning electron microscopy of an inverted blister roof in a case of pemphigus foliaceus. The loss of intercellular adherence could be easily seen with low magnification. The acantholytic keratinocytes displayed an irregular and sometimes polygonal contour. Round cells, typically seen in light microscopy, were also observed. The examination of a blister roof allows ultrastructural documentation of the acantholytic changes.

Realizamos microscopia eletrônica de varredura do teto invertido de uma bolha de um caso de pênfigo foliáceo. Com pequeno aumento, a perda da adesão intercelular pôde ser vista claramente. Os queratinócitos acantolíticos demostraram um contorno irregular, algumas vezes poligonal. Células arredondadas, como vistas tipicamente na microscopia óptica, também foram observadas. O exame de um teto de bolha permite uma documentação ultraestrutural das alterações acantolíticas.

Oxidation is Key for Black Carbon Surface Functionality and Nutrient Retention in Amazon Anthrosols.

Aims: Soil black carbon (BC) has been shown to possess large amounts of cation exchange sites and surface charge, and is viewed as a potential soil amendment to improve nutrient retention and for pollutant remediation. This study investigated the nanoscale distribution of reactive functional groups and the binding of cations on the surface of micron-size BC particles, identified the key processes, and explored the sources of surface functionality and their relative contribution to cation exchange capacity (CEC). Materials and Methods: Elemental microprobe and synchrotron-based Scanning Transmission X-ray Spectromicroscopy (STXM) coupled with Near Edge X-ray Absorption Fine Structure (NEXAFS) spectroscopy were used for nano-scale mapping of cations and reactive functional groups, and further distinction of the sources of reactive functional groups generated either by oxidation of BC surfaces or by adsorption of non- BC organic matter onto the BC surfaces. Their respective contribution to cation adsorption was obtained using a depth profile of a BC-rich Anthrosol from the central Amazon, Brazil. Results and Discussion: Adsorption of Non-BC organic matter is more dominant on the surface of BC particle in topsoil as evidenced by a stronger signal of microbial biomass and humic substances extracts. In comparison, a greater level of oxidation was found on the outerlayer of BC particles in subsoil horizons. Organic C in subsoils was found to generate 23-42% more CEC per unit C than topsoil. Based on CEC per unit C, the capacity of BC in creating CEC was 6-7 times higher than Non-BC, and the BC in deeper horizons had up to 20% higher CEC than the topsoil horizon. Near BC surfaces, higher ratios of Ca/C and K/C in subsoil than topsoil horizons reinforce the observation that BC in subsoil horizons had a higher capacity in binding cations and creating CEC than in the topsoil horizon. Conclusions: Oxidation of BC is suggested to be more efficient and important for creating CEC than the adsorption of non-BC onto BC surfaces, thus identified as being key for BC surface functionality and nutrient retention in Amazon Anthrosols.

Classical Ehlers-Danlos syndrome: clinical, Histological and ultrastructural aspects / Síndrome de Ehlers-Danlos clássica: aspectos clínicos, histológicos e ultraestruturais

A 12-year-old boy with difficulty in wound healing and scars of unusual appearance was examined. Thin, shiny and protruding skin, characterizing pseudotumoral lesions, was observed on his knees and elbows. Loose joints and increased skin elasticity were also observed. Light microscopy showed rare collagen bundles and loosely dispersed collagen fibers. Irregularly distributed elastic tissue was observed, and transmission electron microscopy revealed disorganized collagen fibers. In cross sections under high magnifications, fibers of varying diameters could be seen, as well as an irregular fiber outline. Scanning electron microscopy of the dermis showed disorganized collagen fibers, which were rarely arranged in bundles. Isolated and crossed-over fibers were also found.

Paciente masculino de 12 anos relatou dificuldade em cicatrizar, seguido por cicatrizes de aspecto infrequente . A pele dos joelhos e cotovelos é fina, brilhante e protrusa, caracterizando pseudo- tumores. Além disso apresenta hiperelasticidade cutânea e articular. A microscopia óptica demonstrou raros feixes colágenos, as fibras colágenas encontram-se dispersas. O tecido elástico está presente e secundariamente irregular. A microscopia eletrônica de transmissão também observou fibras colágenas desorganizadas e com cortes transversais em grande aumento evidenciou diâmetros variados e contorno irregular das mesmas. A microscopia eletrônica de varredura da derme demonstrou raros feixes colágenos e fibras colágenas isoladas e entrecruzadas.

Detecção de fibronectina e laminina em cistos teciduais de toxoplasma gondii: ensaios imunocitoquímicos / Detection of fibronectin and laminin in toxoplasma gondii tissue cysts: immunocytochemical assays

Aims: To analyze the existence and distribution of some matrix proteins in tissue cysts of Toxoplasma gondii. Methods: Laminin and fibronectin in tissue cysts of Toxoplasma gondii were detected by confocal microscopy and transmission electron microscopy. Results: Ultrastructural immunocytochemistry showed both glycoproteins in the granular region of tissue cysts, cystic matrix, micronemes, rhoptries, dense granules and rarely at the membrane of bradyzoites of Toxoplasma gondii. Conclusions: The presence of both laminin and fibronectin in secretory organelles and in the apical region of bradyzoites suggests that exocytosis of these glycoproteins can contribute to their interaction with host cells, besides composing the cyst matrix of Toxoplasma gondii.

Scanning electron microscopic study on root canal cleaning effect using sodium hypochlorite at different temperatures / 吉林大学学报(医学版)

Objective To assess the efficacy of NaClO irrigation of root canal at different temperatures.(Methods Thirty) human teeth with single root-canal mandible premolar were instrumented using standard technique,then were divided into 3 groups,carrying on root-canal irrigation.group A: 5.25% NaClO+System B,group B:5.25% NaClO+15% EDTA,group C:5.25% NaClO+System B+15% EDTA.After the teeth root were split,the scanning electron microscope was used to observe the coronal third,middle third and apical third parts.(Results The) amount of remaining debris on root canal wall in group C decreased significantly,compared with group A and B.The differences of coronal third and middle third between group A and B,group B and C,group A and C were significant(P0.05),but there were significant differences between group A,B and C(P

Study on the ultrastructural characteristic of segments of photoreceptors from retinas of neonatal calf / 中华眼底病杂志

Objective To study on the ultrastructural characteristic of segments of photoreceptors from neonatal retinas for supporting donor retina choice of retinal transplantation. Methods Photoreceptors from neonatal calf and adult calf were analysed by scanning electron microscopy and transmission electron microscopy. Results Segments of photoreceptors from neonatal calf appeared the mushroom pattern, in which, distal end of outer segment which was ball shaped formed the head with mushrooms appea rance, and the inner segments along with some of outer segments formed the body with mushrooms appea rance. Within the outer segment, plasma membranes of adjacent evaginations form a disk subsequently. The array of most disks were vertical to the entire length of segments, but some were parallel and slope to. Owing to the incomplete formation, some rim of disk near distal end of outer segment revealed step shaped appearance. The distal end of outer segment displays some processes consisted of membranous discs, much vesicular material and mitochondria, much rough endoplasmic reticulum (RER) and numerous polysomes. Segments of photoreceptor connected with outer nuclear layer via the external limiting membrane. Conclusion The typical morphological structures of outer segments suggest the immature and strong gowth ability of photoreceptors of the retina of neonatal calf, and therefore the competence for donor material of retinal transplantation.

Electron microscopic study of brain tissue and EEG of mouse after acute heat stress / 解放军医学杂志

Objective To study the changes in the central nervous system in adult mice after various degrees of acute heat stress. Methods Adult mice placed in insulated cages were exposed to 24℃, 34℃, 37℃, 38.5℃, 40℃ or 42℃ for 60min respectively with a constant humidity of 60%. The behavior response was carefully monitored. Rectal temperature was measured before the exposure and after the exposure. Electroencephagrams were taken. Then the hippocampal neurons of these animals were examined with transmission electron microscope. Results Heat stress at 34℃ for 60 min only raised the rectal temperature, and heat stress above 37℃ for 60 min not only raised rectal temperature, but also induced water loss and irritability and attempt to escape. Abnormal EEG with increased amplitude and retarded rhythm could be observed. However, when mice were exposed to 24℃ and 34℃ such behavior did not appear. After exposure to 42℃, EEG frequency increased and pathological changes in hippocampus neurons were found. The main ultrastructural changes included degeneration of hippocampal neurons, expansion of space around capillary, decrease in number of synaptic vesicle, and decomposition of synapse. Conclusion Mice were very sensitive to heat stress. An increase in core temperature could induce behavioral thermoregulation. EEG and electron microscopic study revealed changes in the central nervous system after heat stress. Following exposure to high environmental temperature under 40℃, acute dysfunction of brain was reversible. At 42℃, damage to the brain tissue occurred, and most mice died of heat stroke.