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Electron Microscopic Examination (electron + microscopic_examination)
Kinds of Electron Microscopic Examination Selected AbstractsAssessment of parathyroid autotransplantation for preservation of parathyroid function after total thyroidectomyHEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 10 2003Magdy I. El-Sharaky MD Abstract Background. Hypoparathyroidism with permanent hypocalcemia is a well-recognized complication after thyroid surgery. Aim. This study was conducted to assess the role of immediate parathyroid autotransplantation in the preservation of parathyroid function after total thyroidectomy. Patients and Methods. Twenty-eight patients had autotransplantation of parathyroid glands resected or devascularized during total thyroidectomy. Data were collected prospectively regarding demographics, indication for surgery, operative procedure, pathologic diagnosis, number of glands transplanted, and subsequent course. Thyroid nodules were evaluated by ultrasonography, radionuclide scanning, and/or fine-needle aspiration cytology. All patients had serum ionized calcium, phosphorus, and intact parathyroid hormone (PTH) levels measured preoperatively and monitored regularly postoperatively for a period of 14 weeks and again at 6 months after operation. Patients were categorized into three groups according to the number of glands transplanted: one (group 1, n = 6), two (group 2, n = 14), or three glands (group 3, n = 8). In three other volunteers, one parathyroid gland was transplanted in the brachioradialis and subjected to electron microscopy 1, 2, and 4 weeks after transplantation. Results. Total thyroidectomy was performed for malignant disease in 16 patients (57.1%) and for benign disease in 12 (42.9%) patients. All patients reverted to asymptomatic normocalcemia without the need for any medications within 4 to 14 weeks. Normal levels of serum markers were regained slower when one gland was transplanted compared with two or three glands (P < .01). Electron microscopic examination showed evidence of ischemic degeneration in the transplanted tissues 1 week postoperatively. Regeneration started by the second week and coincided with normalization of PTH levels. Optimum resting and nearly normal status of parathyroid tissue was achieved by the fourth week. Conclusions. This study showed that active PTH production coincides with regeneration of parathyroid cells and that autotransplantation of at least two resected or devascularized glands during total thyroidectomy nearly eliminates permanent postoperative hypoparathyroidism, thus improving the safety of total thyroidectomy performed for malignant or benign disease. © 2003 Wiley Periodicals, Inc. Head and Neck 25: 799,807, 2003 [source] Electron microscopic examination of uncultured soil-dwelling bacteriaMICROBIOLOGY AND IMMUNOLOGY, Issue 5 2008Kazunobu Amako ABSTRACT Bacteria living in soil collected from a rice paddy in Fukuoka, Japan, were examined by electron microscopy using a freeze-substitution fixation method. Most of the observed bacteria could be categorized, based on the structure of the cell envelope and overall morphology, into one of five groups: (i) bacterial spore; (ii) Gram-positive type; (iii) Gram-negative type; (iv) Mycobacterium like; and (v) Archaea like. However, a few of the bacteria could not be readily categorized into one of these groups because they had unique cell wall structures, basically resembling those of Gram-negative bacteria, but with the layer corresponding to the peptidoglycan layer in Gram-negative bacteria being extremely thick, like that of the cortex of a bacterial spore. The characteristic morphological features found in many of these uncultured, soil-dwelling cells were the nucleoid being in a condensed state and the cytoplasm being shrunken. We were able to produce similar morphologies in vitro using a Salmonella sp. by culturing under low-temperature, low-nutrient conditions, similar to those found in some natural environments. These unusual morphologies are therefore hypothesized to be characteristic of bacteria in resting or dormant stages. [source] ,, T-cell large granular lymphocyte (LGL) leukemia with spontaneous remissionAMERICAN JOURNAL OF HEMATOLOGY, Issue 3 2004Tsutomu Shichishima Abstract T-cell large granular lymphocyte (LGL) leukemia is a clonal disorder with an indolent clinical course. In July 1995, a 46-year-old Japanese man was admitted to our hospital because his anemia had progressed. He had a white blood cell count of 3.9 × 109/L with 75% lymphocytes, which were intermediate to large and had almost round nuclei and azurophilic granules, and anemia with a red blood cell count (RBC) of 2.69 × 1012/L, hemoglobin (Hb) of 9.5 g/dL, and hematocrit (Hct) of 28.3%. Electron microscopic examination showed that most of the lymphocytes had a parallel tubular array and dense core granules in their cytoplasm. Flow cytometry and Southern blotting of the T-cell antigen receptor (TCR) genes using the peripheral blood species showed monoclonal proliferation of LGLs with a CD3+, TCR,,+, CD4,, CD8,, CD16+, CD56,, CD57,, HLA-DR+ phenotype, and a TCR , gene rearrangement, respectively, suggesting that the patient was diagnosed as having ,, T-cell LGL leukemia. He had no symptoms, organomegaly, or skin lesions. About 1.5 years after diagnosis, the anemia gradually improved with disappearance and appearance of a rearranged band in the TCR-, gene and TCR-, gene, respectively. About 7 years after diagnosis, the anemia improved completely with a RBC of 5.01 × 1012/L, Hb of 14.8 g/dL, and Hct of 44.3%, and he was in complete remission without TCR-, and -, gene rearrangements. He had received no therapy. This is the first report of spontaneous remission of ,, T-cell LGL leukemia. Am. J. Hematol. 75:168,172, 2004. © 2004 Wiley-Liss, Inc. [source] Odorants as cell-type specific activators of a heat shock response in the rat olfactory mucosaTHE JOURNAL OF COMPARATIVE NEUROLOGY, Issue 4 2001Virginian McMillan Carr Abstract Heat shock, or stress, proteins (HSPs) are induced in response to conditions that cause protein denaturation. Activation of cellular stress responses as a protective and survival mechanism is often associated with chemical exposure. One interface between the body and the external environment and chemical or biological agents therein is the olfactory epithelium (OE). To determine whether environmental odorants affect OE HSP expression, rats were exposed to a variety of odorants added to the cage bedding. Odorant exposure led to transient, selective induction of HSP70, HSC70, HSP25, and ubiquitin immunoreactivities (IRs) in supporting cells and subepithelial Bowman's gland acinar cells, two OE non-neuronal cell populations involved with inhalant biotransformation, detoxification, and maintenance of overall OE integrity. Responses exhibited odor specificity and dose dependency. HSP70 and HSC70 IRs occurred throughout the apical region of supporting cells; ubiquitin IR was confined to a supranuclear cone-shaped region. Electron microscopic examination confirmed these observations and, additionally, revealed odor-induced formation of dense vesicular arrays in the cone-like regions. HSP25 IR occurred throughout the entire supporting cell cytoplasm. In contrast to classical stress responses, in which the entire array of stress proteins is induced, no increases in HSP40 and HSP90 IRs were observed. Extended exposure to higher odorant doses caused prolonged activation of the same HSP subset in the non-neuronal cells and severe morphological damage in both supporting cells and olfactory receptor neurons (ORNs), suggesting that non-neuronal cytoprotective stress response mechanisms had been overwhelmed and could no longer adequately maintain OE integrity. Significantly, ORNs showed no stress responses in any of our studies. These findings suggest a novel role for these HSPs in olfaction and, in turn, possible involvement in other normal neurophysiological processes. J. Comp. Neurol. 432:425,439, 2001. © 2001 Wiley-Liss, Inc. [source] Hypermelanocytic guttate and macular segmental hypomelanosisBRITISH JOURNAL OF DERMATOLOGY, Issue 3 2004W. Westerhof Summary We report two sisters, 27 and 30 years of age, with a cutaneous pigmentary anomaly, which seems to be a new entity. At the age of 26 years the elder sister developed an asymptomatic and persistent rash consisting of discrete, grouped, round to oval, guttate and nummular, hypopigmented macules, 0·2,5 cm in diameter. The distribution of the lesions was unilateral. They were located on the right side of the thorax with a moderately sharp demarcation in the mid-line and ran in a segmental distribution over the right arm, hand and fingers. Microscopic examination of lesional skin scrapings was negative for fungi. Examination with Wood's light accentuated the lesions from the surrounding normal skin. The younger sister had experienced identical, mostly guttate, skin lesions for many years, which at examination were distributed on all extremities and buttocks, and to a lesser degree on the trunk, but here in a segmental distribution. Histological examination (Masson,Fontana staining) of lesional skin of both sisters was identical. A slightly thinned epidermis and a marked decrease in pigmentation of the epidermal basal layer was seen. Electron microscopic examination of lesional skin showed an overall linear increase of morphologically and cytologically normal melanocytes just above the epidermal basal membrane. At many places the density of melanocytes was so high that the keratinocytes were displaced from the basal layer. The melanocytic dendrites extended into the suprabasal layer. The keratinocytes of lesional skin showed a decreased number of melanosomes. It is paradoxical that a hypomelanotic macule shows a histological picture of an increase in normal functioning melanocytes. In all probability a deficient melanosome transfer is responsible for this unexpected phenomenon. [source] Choroidal Langerhans' cell histiocytosisACTA OPHTHALMOLOGICA, Issue 1 2000In Taek Kim ABSTRACT. Purpose: To report a patient with choroidal Langerhans' cell histiocytosis. Methods: A solitary tumor was found in the left eye of a 49-year-old male who had no definite history of systemic disorders, but had observed visual disturbances for a period of 1 month. Ultrasonography, fluorescein angiography, and indocyanine green angiography were performed and the eyeball was enucleated. We prepared the specimen for microscopic examinations. Results: Fluorescein angiographic findings of the lesion were mottled hyperfluorescence in the arteriovenous phase and strong hyperfluorescence in the late phase. Hypofluorescence in both early and late phases showed on indocyanine green angiogram. The lesion of choroid was widely infiltrated by histiocytes, though no extraocular invasion was found. Immunohistochemical studies including S-100 and CD 68 staining revealed characteristic features of Langerhans' cell histiocytosis. Electron microscopic examination of the histiocytes showed histiocytosis X body (Birbeck granule) in the cytoplasm and indented nucleus. Conclusion: We consider that this is a case of choroidal Langerhans' cell histiocytosis with no evidence of systemic lesions. [source] Innervation of interneurons immunoreactive for VIP by intrinsically bursting pyramidal cells and fast-spiking interneurons in infragranular layers of juvenile rat neocortexEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 1 2002Jochen F. Staiger Abstract Cortical columns contain specific neuronal populations with characteristic sets of connections. This wiring forms the structural basis of dynamic information processing. However, at the single-cell level little is known about specific connectivity patterns. We performed experiments in infragranular layers (V and VI) of rat somatosensory cortex, to clarify further the input patterns of inhibitory interneurons immunoreactive (ir) for vasoactive intestinal polypeptide (VIP). Neurons in acute slices were electrophysiologically characterized using whole-cell recordings and filled with biocytin. This allowed us to determine their firing pattern as regular-spiking, intrinsically bursting and fast-spiking, respectively. Biocytin was revealed histochemically and VIP immunohistochemically. Sections were examined for contacts between the axons of the filled neurons and the VIP-ir targets. Twenty pyramidal cells and five nonpyramidal (inter)neurons were recovered and sufficiently stained for further analysis. Regular-spiking pyramidal cells displayed no axonal boutons in contact with VIP-ir targets. In contrast, intrinsically bursting layer V pyramidal cells showed four putative single contacts with a proximal dendrite of VIP neurons. Fast-spiking interneurons formed contacts with two to six VIP neurons, preferentially at their somata. Single as well as multiple contacts on individual target cells were found. Electron microscopic examinations showed that light-microscopically determined contacts represent sites of synaptic interactions. Our results suggest that, within infragranular local cortical circuits, (i) fast-spiking interneurons are more likely to influence VIP cells than are pyramidal cells and (ii) pyramidal cell input probably needs to be highly convergent to fire VIP target cells. [source] The erosive potential of flavoured sparkling water drinksINTERNATIONAL JOURNAL OF PAEDIATRIC DENTISTRY, Issue 2 2007CATRIONA J. BROWN Objective., The potential role of acidic drinks in the aetiology of dental erosion is well recognized. Whilst the wide-scale consumption of bottled waters is unlikely to contribute significantly to erosion, the role of flavoured sparkling water drinks is unclear. The aim of this study was to determine the pH, titratable acidity and in vitro erosive potential of a selection of these drinks drawn from the UK market to identify what dietary advice would be appropriate in relation to their consumption. Methods., pH was measured using a pH electrode and titratable acidity recorded by titration with 0.1- m NaOH. Erosive potential was assessed using an in vitro dissolution assay with hydroxyapatite powder and electron microscopic examination of surface enamel of extracted human teeth, following exposure to the flavoured sparkling waters for 30 min. Results., All of the flavoured waters tested showed appreciable titratable acidity (0.344,0.663 mmol) and low pH (2.74,3.34). In the hydroxyapatite dissolution assay, all of the waters demonstrated erosive potential (89,143%) similar to or greater than that of pure orange juice, an established erosive drink. Exposure of the extracted teeth to the flavoured waters resulted in surface changes consistent with erosive dissolution. Conclusions., Flavoured sparkling waters should be considered as potentially erosive, and preventive advice on their consumption should recognize them as potentially acidic drinks rather than water with flavouring. [source] Dentition in the African catfishes Andersonia (Amphiliidae) and Siluranodon (Schilbeidae) previously considered toothlessJOURNAL OF FISH BIOLOGY, Issue 1 2004A. S. Golubtsov Based on light and scanning electron microscopic examination of their morphology, the dentition on both the premaxilla and dentary of Andersonia(Amphiliidae) and Siluranodon(Schilbeidae) catfishes is described from samples taken from tributaries of the White Nile in south-western Ethiopia. These monotypic African genera were previously believed to lack teeth on the lower jaw in Andersonia and on both jaws in Siluranodon. Siluranodon exhibits an ontogenetic reduction: teeth were less frequently found in larger individuals than in smaller ones. In contrast to the adults of all other schilbeids, whose oral teeth are arranged in multiserial (or at least, biserial) bands, Siluranodon has uniserial teeth on both the premaxilla and the dentary. The adaptive, ontogenetic and phylogenetic aspects of jaw-tooth reduction in catfishes are discussed. [source] Mechanical Behavior and Failure Analysis of Prosthetic Retaining Screws after Long-term Use In Vivo.JOURNAL OF PROSTHODONTICS, Issue 3 2008Part 1: Characterization of Adhesive Wear, Structure of Retaining Screws Abstract Purpose: The general aim of this study and those presented in Parts 2,4 of this series was to characterize the structure, properties, wear, and fracture of prosthetic retaining screws in fixed detachable hybrid prostheses after long-term use in vivo. This part of the overall investigation addresses whether there are differences in thread wear between the screws closest to the fulcrum and those that are farthest from the fulcrum in fixed detachable hybrid prostheses. Materials and Methods: The total number of prosthetic retaining screws used in this study was 100 (10 new and 90 used). New screws (controls) from Nobel Biocare (NB) were divided into Group 1 (slotted) and Group 2 (hexed). Ninety used screws (in service 18,120 months) were retrieved from fixed detachable hybrid prostheses in 18 patients (5 screws from each patient, 60 from NB and 30 from Sterngold). The used screws were divided into 18 groups. Additionally, each group was subdivided into A and B categories. Category A contained the middle three prosthetic screws, which were considered the farthest screws from the fulcrum line. Category B contained the most posterior two screws, which were considered the screws closest to the fulcrum line. All 100 screws were subjected to thorough, nondestructive testing. Results: Light and scanning electron microscopic examination of all used screws for each group revealed surface deterioration of the active profile of the screw threads consistent with adhesive wear. The observed thread profile deterioration ranged from mild to severe. The wear was aggressive enough to cause galling, which led to thinning of the threads and, in severe cases, to knife-edges at thread crests. In ten groups, the most anterior three screws exhibited more wear than the most posterior two screws. In addition to thread wear, severe plastic deformation was detected on the bottom part of each screw for three groups, and a long external longitudinal crack was detected in one screw of Group 2. Conclusions: The findings of this study and those presented in Parts 2,4 demonstrate that different retaining screws from the same manufacturer and/or from different manufacturers have different geometrical design, microstructures, major alloy constituents, and microhardness, and that these differences influence their preload and fractured load values. In this part of the overall investigation, the occurrence of galling as a result of wear involving prosthetic retaining screws appears to be an inevitable and unavoidable consequence of long-term use in vivo in fixed detachable hybrid prostheses regardless of the intended/original preload value. The galling rate is greater on the middle three screws compared to the most posterior two screws in fixed detachable hybrid prostheses. The wear pattern is consistent with an adhesive wear mechanism; however, this study does not provide enough data to support a definitive analysis. [source] Influence of Grain Phase on Slag Corrosion of Low-Cement Castable RefractoriesJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 2 2001Hossain Sarpoolaky The grain phase has a significant influence on the extent and mechanism of attack of low-cement castables with similar bond systems in a crucible corrosion test. The general corrosion mechanism, as determined by post mortem scanning electron microscopic examination of corroded samples and thermodynamic calculations for all four grain types examined (white-fused alumina (WFA), tabular alumina (TA), brown-fused alumina (BFA), and alumina-rich spinel (S)), involves initial reaction of the most penetrating slag (enriched in calcium, manganese, and iron, because these elements diffuse rapidly) with the fine alumina and calcium aluminates of the matrix. This reaction gives a CaO-rich local liquid, which can then react with each grain predominantly to form calcium hexaluminate (CA6) and hercynitic spinel. In the WFA system, a complete CA6 layer forms around the grain, whereas in the TA system, this layer is incomplete. In both systems, extensive penetration occurs, although corrosion is low. In the BFA system, titanates are released from the grain into the bond, leading to increased densification of the refractory, via liquid-phase sintering, and consequent low penetration. However, the resulting fluid liquid dissolves easily in the slag, so that corrosive wear is high, even though a CA6 layer forms around the grain. In the S grain system, uptake of the rapidly diffusing cations into the spinel crystal structure leads to silica-rich and viscous local liquid, which leads to low penetration and corrosion. [source] Transplantation of bone marrow mesenchymal stem cells reduces lesion volume and induces axonal regrowth of injured spinal cordNEUROPATHOLOGY, Issue 3 2010Weidong Gu It has been demonstrated that transplantation of bone marrow mesenchymal stem cells (BMSCs) improves recovery of injured spinal cord in animal models. However, the mechanism of how BMSCs promote repair of injured spinal cord remains under investigation. The present study investigated the neural differentiation of BMSCs, the lesion volume and axonal regrowth of injured spinal cord after transplantation. Seven days after spinal cord injury, 3 × 105 BMSCs or PBS (control) was delivered into the injury epicenter of the spinal cord. At 8 weeks after spinal cord injury, transplantation of BMSCs reduced the volume of cavity and increased spared white matter as compared to the control. BMSCs did not express the cell marker of neurons, astrocytes and oligodendrocytes in injured spinal cord. Transmission electron microscopic examination displayed an increase in the number of axons in BMSC rats. The effect of BMSCs on growth of neuronal process was further investigated by using a coculture system. The length and the number of neurites from spinal neurons significantly increased when they cocultured with BMSCs. PCR and immunochemical analysis showed that BMSCs expressed brain-derived neurotrophic factor (BDNF) and glia cell line-derived neurotrophic factor (GDNF). These findings demonstrate that transplantation of BMSCs reduces lesion volume and promotes axonal regrowth of injured spinal cord. [source] Microvasculature of the human cerebral white matter: Arteries of the deep white matterNEUROPATHOLOGY, Issue 2 2003Hiroko Nonaka The vascular architecture of the human cerebral deep white matter was studied using soft X-ray and diaphanized specimens, achieved by intra-arterial injection of barium and vascular stain respectively, and also by electron microscopic examination of the corrosion cast of arteries in normal adult brains. The deep white matter arteries passed through the cerebral cortex with a few branches to the cortex and ran straight through the white matter. The arteries concentrated ventriculopetally to the white matter around the lateral ventricle. Anastomoses were noted around the ventricular wall at the terminals of the deep white matter arteries. No centrifugal branches irrigating the periventricular white matter from the lenticulo-striate arteries were observed in the present study. The presence of anastomoses among the terminal branches of deep white matter arteries protects against ischemic change or infarction in this area from an occlusion of a single deep white matter artery. This may lead to development of terminal zone infarction from ischemia or vascular diseases, affecting multiple deep white matter arteries. The subcortical and deep white matter arteries had thick adventitial sheaths and large adventitial spaces in the white matter but not in the cortex. The presence or absence of the adventitial space is regarded as another characteristic difference between the arteries in the white matter and cortex. This difference may influence pathological changes in vascular lesions in these respective areas. [source] Microscopic analysis and seasonality of gemma production in the freshwater red alga Hildenbrandia angolensis (Hildenbrandiales, Rhodophyta)PHYCOLOGICAL RESEARCH, Issue 4 2000Alison R. Sherwood SUMMARY The development and release of the unique vegetative propagules of the freshwater encrusting alga Hildenbrandia angolensis Welwitsch ex West et West, gemmae, were studied using several different microscopic and histochemical techniques. In addition, the seasonality of gemma production was monitored bimonthly over a 12-month period in two spring-fed streams in Texas, USA. Gemmae differentiate within the thallus and are subsequently released from the surface of the crust. Release of the gemmae most likely occurs by digestion of surrounding cells, as suggested by the presence of starch granules and lipid globules in the region between the released gemma and the thallus. The initial separation of the gemmae from the thallus occurs from the sides of the gemma or the bottom, or possibly simultaneously. Contrary to previous studies, we have observed that gemma production occurs endogenously within the thallus of freshwater Hildenbrandia, rather than on the surface of the crust in raised structures. Histochemical tests and electron microscopic examination indicate that the cells of the gemmae contain a large amount of floridean starch. The starch granules frequently form rings surrounding the nuclei of both gemma and thallus cells; a feature infrequently reported for florideophyte red algae. Our seasonality investigations indicate that large fluctuations in gemma production occur over 1 year, but at least some gemma production continues year-round in the streams examined. [source] A novel procedure for gentle isolation and separation of intact infected and uninfected protoplasts from the central tissue of Vicia faba L. root nodulesPLANT CELL & ENVIRONMENT, Issue 7 2003E. PEITER ABSTRACT The central tissue of Vicia faba L. root nodules is composed of cells infected with Rhizobium bacteroids and uninfected cells. For the study of various processes, such as plasma membrane transport, it is essential to separate both cell types. Initial attempts to isolate protoplasts according to protocols described in the literature resulted in non-spherical and osmotically inactive material, which is in agreement with previous descriptions. In the study reported herein, it was shown that the plasma membrane of non-spherical infected protoplasts is not intact. A new isolation and separation protocol was developed, based on dissection of the nodule prior to cell wall digestion, non-shaking digestion in hypertonic medium, and a combined procedure for release of protoplasts into slightly hypotonic medium and separation of protoplast fractions by isopycnic density gradient centrifugation. Infected and uninfected protoplasts that were isolated according to this protocol were spherical, osmotically active and excluded propidium iodide, confirming the intactness of their plasma membrane. The common fluorescein diacetate test was shown to be artefactual in infected cells, since viable bacteroids also stain in defective cells. Light and electron microscopic examination of infected protoplasts showed that protoplasts still contained starch after isolation and bacteroids in intact protoplasts had unusually high amounts of polyhydroxybutyrate. The vacuoles of infected protoplasts contained protein and membrane-enclosed structures, and were of non-acid pH; traits that are typical of protein storage vacuoles. [source] A case of generalized argyria after ingestion of colloidal silver solutionAMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 3 2009Yangho Kim Abstract A 58-year-old woman was referred to our hospital due to progressive skin darkening, which began 5 months previously. The patient had strikingly diffuse blue-gray discoloration of the skin, most prominent in sun-exposed areas, especially her face and hands. The oral mucosa, tongue, gums, eye conjunctiva, ears, nail beds, and trunk were also involved. Bluish-gray discoloration of all nails was aggravated by cold weather. She had ingested 1 L of colloidal silver solution daily for approximately 16 months as a traditional remedy. Her serum silver concentration was 381 ng/ml which was a very high (reference level: <15 ng/ml). Light microscopic examination of a punch biopsy specimen from her nose revealed fine, minute, round, and brown-black granules deposited in the basement membrane of hair follicular epithelium. Scanning electron microscopic examination showed electron-dense granules deposited in the intercellular space of sweat glands. Energy disperse X-ray spectrometry analysis demonstrated peaks for silver and sulfur in the dense black deposits. The ingestion of colloidal silver appears to be an increasing practice among patients using alternative health practices. All silver-containing products including colloidal silver should be labeled with a clear warning to prevent argyria, especially in alternative health practices. Am. J. Ind. Med. 52:246,250, 2009. © 2008 Wiley-Liss, Inc. [source] Epidermolysis bullosa simplex in Japanese and Korean patients: genetic studies in 19 casesBRITISH JOURNAL OF DERMATOLOGY, Issue 2 2006K. Yasukawa Summary Background, Epidermolysis bullosa simplex (EBS) comprises a group of hereditary bullous diseases characterized by intraepidermal blistering caused by mutations in either keratin gene, KRT5 or KRT14. Significant correlation between the position of mutations within these proteins and the clinical severity of EBS has been noted. A recent report showed EBS cases in Israel had unique genetic features compared with European or U.S.A. associated families, which suggests that the ethnic and geographical features of EBS patients may be different. Objectives, To assess the possibility that EBS may present with certain specific features in Japanese and Koreans and to identify additional EBS mutations for genotype/phenotype correlation. Methods, EBS was clinically diagnosed and confirmed by transmission electron microscopic examination of a skin biopsy. Mutation analysis of KRT5 and KRT14 was performed by direct sequencing in 17 Japanese and two Korean EBS patients. Results, We have identified six novel KRT5 missense mutations (V143D, D158V, V186M, Q191P, R352S, G517D). R352S is the first mutation in the 2A domain. Most of these novel mutations changed amino acids that were evolutionarily conserved. Eight including all five mutations in EBS-Dowling,Meara patients have been previously reported. We were unable to detect mutations in five sporadic EBS-Koebner patients. The proportion of mutations in KRT5 (11 of 14; 78%) is higher than that for KRT14 mutations (3 of 14; 21%) in these Japanese and Korean EBS patients. Conclusions, Japanese and Korean patients with EBS showed very similar phenotype and genotype correlations with patients from Western countries. Whether the higher proportion of KRT5 mutations is a definite characteristic of Japanese and Korean patients with EBS or not, requires further research into mutations in Japanese and Korean people. [source] How to tell dystrophies of Bowman's layer (Reis-Bücklers and Thiel-Behnke) from one anotherACTA OPHTHALMOLOGICA, Issue 2009T KIVELÄ Purpose To discuss difficulties encountered in differentiating two classic dystrophies of the Bowman layer caused by mutations of the TGFBI gene: Thiel,Behnke corneal dystrophy (TBCD) and Reis,Bücklers corneal dystrophy (RBCD). Methods Critical review of published data by the IC3D group and personal experience of the author as an ophthalmic pathologist and clinician. Results It has traditionally been difficult to recognise and distinguish TBCD and RBCD, so much so that some early papers claimed to describe the ultrastructure of RBCD actually analysed tissue from patients with TBCD; the known entity of RBCD was described as an unusual variant of granular corneal dystrophy; and Waardenburg-Jonkers dystrophy appeared for eyars in textbooks although their patients had TBCD. The main problem is that both dystrophies are fairly rare and clinicians seldom have personal prior experience or adequate literature knowledge of both when they encounter a patient; and the literature with its frequent errors in diagnoses has not been that helpful. Conclusion TBCD and RBCD may be differentiated by careful clinical and ophthalmic pathologic examination if the clinician and pathologist are experienced; genetic or electron microscopic examination is needed for unequivocal confirmation. [source] A variant TGFBI corneal dystrophy from G623D mutation with an unusual amyloidogenic phenotypeACTA OPHTHALMOLOGICA, Issue 2009HT AGOSTINI Purpose To present a unique corneal dystrophy never before described in a German family carrying the Gly623Asp mutation of the TGFBI gene with late clinical onset. Methods Clinical documentation and isolation of genomic DNA from peripheral blood leucocytes were obtained from each family member examined. Exons 3, 4, 5, and 11 to 14 of the TGFBI gene were sequenced. 5 corneal buttons of 3 affected siblings were excised at the time of penetrating keratoplasty. Light and electron microscopic examination were performed including immunohistochemistry with antibodies against Keratoepithelin (KE) 2 and 15. Results Specimens showed changes in Bowman's layer and the adjacent stroma. Congo red-positive amyloid deposits were found within the epithelium in one cornea, in Bowman's layer and in the anterior stroma of all specimens, also showing KE2- but not KE15-immunostaining. EM revealed deposits located in the anterior stroma and Bowman's layer and the basal area of some epithelial cells. These areas were strongly Alcian blue-positive but negative in the Masson-Trichrom-stain. Only affected patients had a heterozygous missense mutation in exon 14 of the TGFBI gene (G->A transition at nucleotide 1915) with the change Gly623Asp in the keratoepithelin protein. Conclusion In contrast to the patient carrying the Gly623Asp mutation of the TGFBI gene described by Afshari et al., our cases presented with Salzmann nodular degeneration like clinical features with KE2 positive amyloid. The reason for this now "meeting the expectation histological phenotype" is unclear. The histological findings emphasize that this is a unique corneal dystrophy which shares no clinical characteristics with Reis-Bücklers dystrophy and should be treated as a distinct entity. [source] Evidence for vesicular glutamate transporter synapses onto gonadotropin-releasing hormone and other neurons in the rat medial preoptic areaEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 12 2003J. Kiss Abstract The medial preoptic area is a key structure in the control of reproduction. Several data suggest that excitatory amino acids are involved in the regulation of this function and the major site of this action is the medial preoptic region. Data concerning the neuromorphology of the glutamatergic innervation of the medial preoptic area are fragmentary. The present investigations were focused on: (i) the morphology of the vesicular glutamate transporter 1 (VGluT1)- and vesicular glutamate transporter 2 (VGluT2)-immunoreactive nerve terminals, which are considered to be specific to presumed glutamatergic neuronal elements, in the medial preoptic area of rat; and (ii) the relationship between these glutamate transporter-positive endings and the gonadotropin-releasing hormone (GnRH) neurons in the region. Single- and double-label immunocytochemistry was used at the light and electron microscopic level. There was a weak to moderate density of VGluT1- and a moderate to intense density of VGluT2-immunoreactive elements in the medial preoptic area. Electron microscopy revealed that both VGluT1- and VGluT2-immunoreactive boutons made asymmetric type synaptic contacts with unlabelled neurons. VGluT2-labelled, but not VGluT1-labelled, axon terminals established asymmetric synaptic contacts on GnRH-immunostained neurons, mainly on their dendrites. The present findings are the first electron microscopic examinations on the glutamatergic innervation of the rat medial preoptic area. They provide direct neuromorphological evidence for the existence of direct glutamatergic innervation of GnRH and other neurons in the rat medial preoptic area. [source] Homing of transplanted bone marrow cells in livers of Schistosoma mansoni -infected miceAPMIS, Issue 4 2010NAGWA ELKHAFIF Elkhafif N, Voss B, Hammam O, Yehia H, Mansy S, Akl M, Boehm S, Mahmoud S, El Bendary O, El Fandy G. Homing of transplanted bone marrow cells in livers of Schistosoma mansoni -infected mice. APMIS 2010; 118: 277,87. The efficiency of differentiation of bone marrow cells (BMCs) into hepatocytes in vivo and its importance in physiopathological processes is still debated. Murine schistosomiasis was used as a liver injury model and unfractionated male mice BMCs were transplanted through intrahepatic injection into non-irradiated Schistosoma mansoni -infected female mice on their 16th week post-infection. Two weeks after bone marrow transplantation, mice were sacrificed on a weekly basis until 10 weeks. Tracing of male donor-derived cells in female recipient mice livers was carried out by the detection of Y chromosome expression by fluorescent in situ hybridization (FISH) and also of chromodomain Y-linked (CDYL) protein by indirect immunofluorescence (IF). Their transformation into hepatocytes was studied by double labelling indirect IF using antibodies directed against CDYL and mouse albumin. Histopathological and electron microscopic examinations revealed the presence of small hepatocyte-like cells in the periportal tracts and in between the hepatocytes facing the sinusoids. Donor-derived cells showing Y chromosome by FISH and expressing CDYL protein by IF were recovered in the infected transplanted livers. The initial number of these cells increased with increased post-transplantation time. Cells were mainly localized in the periphery of schistosoma granuloma. Few donor-derived cells appeared within the hepatic parenchymal tissue and showed positivity for albumin secretion by double labelling with IF. We suggest that transplanted bone marrow stem cells can repopulate the Schistosoma -infected liver of immunocompetent mice. Their differentiation is a complex event controlled by many factors and needs to be further characterized extensively. The extent and type of liver injury and the number of transplanted cells are important variables in the process of stem cell engraftment and differentiation into functioning hepatic cells that still need to be defined. [source] | ||||||||||||||||