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Summary Stem cell factor (SCF) is a ligand of the molecule Kit, which is expressed in mast cells and is important for mast cell proliferation, migration and survival. Mast cell tumours (MCTs) are associated with mutations of c-kit, a proto-oncogene encoding the Kit protein. In this study, we examined SCF expression in 23 samples of feline MCTs. SCF expression was detected in 10 cutaneous MCTs and a case of splenic mastocytosis. In the cutaneous MCTs, SCF-positive tumour cells were located at the margins. Kit was expressed in eight of the 10 cutaneous cases of SCF-expressing MCTs. In these cases, Kit-positive cells were located near to SCF-positive cells, and SCF/Kit double-positive tumour cells were found. Ki67-positive tumour cells were not found near to SCF-positive cells. These results suggest that SCF autocrine/paracrine mechanisms are involved in the expansion of cutaneous MCTs, but not in tumour proliferation. [ABSTRACT FROM AUTHOR]

Abstract Lipoid pneumonia is an uncommon noninfectious inflammatory lung disease characterized by lipid deposition in the alveoli, and its etiology and treatment have not been elucidated. We report the case of a 32-year-old woman who developed lipoid pneumonia 9 months after allogeneic hematopoietic stem cell transplant for chronic myelogenous leukemia in lymphoid blast crisis. She complained of progressive cough and dyspnea shortly after discontinuation of immunosuppressive therapy given for graft-vs-host disease. Computed tomography demonstrated diffuse ground-glass opacities in the lungs, and pulmonary function test revealed restrictive impairment. Bronchoalveolar lavage fluid showed milky appearance, and transbronchial lung biopsy specimen revealed foamy macrophages infiltrating the alveoli. Based on these findings, she was diagnosed as having lipoid pneumonia. Prednisolone (1 mg/kg/d) promptly improved the symptoms, pulmonary shadows, and pulmonary function. The findings and clinical course of this case suggest that lipoid pneumonia should be recognized as one of the pulmonary complications of allogeneic hematopoietic stem cell transplantation. [ABSTRACT FROM AUTHOR]

Summary The aim of this study was to investigate the effect of Newcastle disease virus (NDV) on the chicken pancreas. A virulent 9a5b mutant NDV isolate was inoculated intranasally into 32-day-old specific pathogen-free white Leghorn chickens. The pancreas was examined grossly and fixed for histopathological, immunohistochemical and electron microscopical investigations. Inflammatory changes were observed in the peripancreatic tissue at the early stage of infection (12 h post infection) and became more prevalent towards the end of the experiment. Multifocal areas of necrotizing inflammation were detected in the exocrine portion of the pancreas by 5 days post infection (dpi) and became more severe at 10 dpi. The endocrine islets were generally preserved, but slight degenerative changes were observed at 10 dpi. Immunohistochemically, NDV-nucleoprotein (NDV-NP) signals were detected in the peripancreatic tissues (associated with macrophages and other lymphoid cells) by 1 dpi. In the exocrine portion of the pancreas, NDV-NP signals were detected at 5 dpi and increased in intensity and distribution by 10 dpi. NDV particles were confirmed in the cytoplasm of exocrine acinar cells by transmission electron microscopy. CD3-positive cells were observed in the peripancreatic tissues earlier than in the pancreatic tissue. Moreover, in comparison with control chickens, insulin immunoexpression was unchanged, except on the last day of the experiment, when it was slightly reduced. The 9a5b NDV infection induced an inflammatory reaction and viral replication in the peripancreatic tissues earlier than in the pancreatic tissue. Furthermore, necrosis affected mainly the exocrine portion of the pancreas, while the endocrine portion was generally unaffected. [ABSTRACT FROM AUTHOR]

A female 4-month-old Holstein-Friesian calf was presented in heart failure. Microscopical examination of samples of the cardiac wall taken at necropsy examination revealed numerous aggregates of Purkinje fibres, particularly in the perivascular areas. Some Purkinje fibres were stained strongly with phosphotungstic acid haematoxylin and immunohistochemically were shown to express alpha smooth muscle actin, indicating an embryonic-like Purkinje fibre phenotype. A diagnosis of congenital multifocal increase of Purkinje fibres was made. The histological features of this case resemble multifocal cardiac Purkinje cell tumour of the heart in man. [ABSTRACT FROM AUTHOR]

Abstract: Background and aims: Since there is little information derived from prospective studies on the amount of alcohol drinking required to induce hyperuricaemia, we attempted to address this issue in a Japanese population. Methods and results: A total of 3310 Japanese men aged 20–54 years that were free of hyperuricaemia were classified according to their alcohol intake per week at baseline. Incident hyperuricaemia, defined as >7.0 mg/dl and/or taking medication for hyperuricaemia, was assessed through annual heath examinations for 6 years after the baseline examination. During follow-up, 529 incident cases of hyperuricaemia occurred. There was a positive, dose-response relationship between alcohol intake and the risk of incident hyperuricaemia. The hazard ratio (95% confidence interval) for hyperuricaemia in drinkers compared with non-drinkers was 1.10 (0.85–1.42) for <10.0 drinks/week, 1.40 (1.07–1.84) for 10.0–19.9 drinks/week, 1.64 (1.23–2.21) for 20.0–29.9 drinks/week and 1.98 (1.40–2.80) for ≥30.0 drinks/week (one drink contained 11.5 g of ethanol) after adjusting for age, baseline serum uric acid, body mass index, smoking habits, exercise habits, serum creatinine, blood pressure, serum cholesterol and blood glucose. The fraction of hyperuricaemia in the population attributable to alcohol intake was 21.6%. A clear dose-response pattern was observed for both beer and sake, when the consumption of these two beverages was analysed separately. Conclusion: Habitual alcohol intake significantly contributed to the development of hyperuricaemia in Japanese men, regardless of type of alcoholic beverage consumed. Therefore, it is essential to reduce excessive alcohol intake to prevent and manage hyperuricaemia. [Copyright &y& Elsevier]

Summary: Formalin-fixed and paraffin wax-embedded (FFPE) tissue sections are usually used for histopathological and immunohistochemical analyses in prion diseases in animals and man. However, formalin fixation cross-links proteins, reducing disease-associated prion protein (PrPSc) immunolabelling. To detect PrPSc in animals naturally affected with bovine spongiform encephalopathy (BSE) and scrapie, we applied minimal pretreatment with sodium hydroxide (NaOH). This simple pretreatment, combined with enzymatic digestion using proteinase K (PK), was equally effective in the detection of PrPSc in FFPE tissue, and superior in terms of speed, compared with the usual autoclaving method. The most effective results, without any section loss, were obtained with 10μg/ml PK in phosphate buffered saline containing 0.1% Triton-X at room temperature for 10min and 150mM NaOH at 60°C for 10min. By this simple procedure, PrPSc was visualized in the brain of animals with BSE and scrapie using a range of anti-PrP primary antibodies. [ABSTRACT FROM AUTHOR]

Summary: Transmissible spongiform encephalopathies (TSEs) induce fatal neurodegenerative diseases in man and animals. The present study demonstrates immunohistochemically the presence of disease-associated prion protein (PrPSc) in the epithelial cell rests of Malassez (ERM) of mice experimentally infected with ME7 scrapie by the intracerebral route. Mouse bioassay of scrapie-infected dental tissue revealed prolonged incubation periods, suggesting that there are relatively low amounts of infectious agent in dental tissue compared with the brain. These findings indicate that PrPSc may spread from the brain to the ERM along the cranial nerves via the trigeminal ganglion that innervates the dental tissues. Dental tissue might therefore be a potential source of PrPSc for horizontal transmission of TSEs. [ABSTRACT FROM AUTHOR]

Abstract: There is no in vitro model of the critical periods for developmental plasticity, the time windows of plastic changes during development, which may hinder in-depth mechanistic analysis. We have shown previously that the corticospinal tract with synaptic connections can be reconstructed in in vitro co-cultures using slices of the sensorimotor cortex and spinal cord of the rat. In our in vitro system, corticospinal synapses form widely over spinal gray matter during early development, after which those on the ventral side are eliminated in an activity and N-methyl-d-aspartate (NMDA)-dependent manner. A detailed quantitative analysis of the time course of sensitivity to an NMDA blocker was made with this system. Synapse distribution was evaluated by recording field excitatory post-synaptic potentials evoked by deep cortical layer stimulation. Corticospinal axon terminal distribution was examined by anterograde labeling with biocytin. We showed that the d-2-amino-5-phosphonovaleric acid (APV) effect is irreversible for at least the length of culture. When APV was removed from the medium before 6 days in vitro(DIV) or after 11 DIV, elimination of ventral synapses was not blocked. APV sensitivity showed a clearly defined time window. A 6–11 DIV application was necessary and sufficient for the full, irreversible block of synapse elimination. From 6–11 DIV, APV sensitivity seems to decrease gradually but not linearly. This system provides an in vitro model of critical periods for developmental plasticity of central synapses which up to now has not been available. [Copyright &y& Elsevier]

Local structures around Y and Zr solutes in bcc-Fe are studied for the melt-quenched ribbons by X-ray absorption fine structure (XAFS). The melt-quenched ribbons of Fe99Y1 and Fe99Zr1 are confirmed as a super-saturated solid solution by X-ray diffraction and DSC. XAFS results indicate that the local structures around Y and Zr for the melt-quenched Fe99Y1 and Fe99Zr1 are similar to those for the Fe-rich intermetallic compounds; Fe17Y2 for Fe99Y1 and Fe2Zr for Fe99Zr1. Prior to the apparent precipitation of the intermetallic compounds by annealing, the precursor of intermetallic compounds, about 1 nm in a diameter, are formed in the melt-quenched Fe99Y1 and Fe99Zr1. The large size mismatch of the atom between solutes (Y and Zr) and host (Fe) is responsible for it. This result shows a sharp contrast to that for the case of Cu and Ga in bcc-Fe, in which Cu and Ga occupy a substitutional site of bcc-Fe. [Copyright &y& Elsevier]

We investigated the local atomic structure in GeSi alloy experimentally and theoretically. Extended X-ray absorption fine structure measurements in Czochralski-grown Ge1−xSix bulk alloys showed that the Ge&z.sbnd;Ge and Ge&z.sbnd;Si bond lengths maintain distinctly different lengths and vary linearly with alloy composition across the whole composition range 0. This is in good agreement with the expectation derived from ab initio electronic structure calculations. The result indicates that the bond lengths and bond angles are distorted with alloy composition in GeSi. [Copyright &y& Elsevier]

Thermal behavior was examined using DSC and TG for the samples prepared by dissolving LiClO4 in several polyoxyethylene/polyethylenimine (PEO/PEI) blends (7/3–9.5/0.5 by repeat units) along with their lithium ion conductivity. Concerning the matrix polymers, while the pristine PEO and PEI began to thermally decompose at 185 and 230 °C, respectively, the (8/2) PEO/PEI blend had lost only 6.5% of its weight before 300 °C was reached. Dissolution of LiClO4 made the systems thermally even more robust: [(8/2) PEO/PEI]10–LiClO4 suffered practically no weight loss below 300 °C. So far [(8/2) PEO/PEI]10–LiClO4 has been our best-behaving SPE (σ=2.2×10−4 S cm−1 at 77 °C and 2.5×10−6 S cm−1 at 30 °C): it is less conductive than a previously reported PEO12–LiClO4 by a factor of 2.2 at 77 °C, but its conductivity drop due to the matrix crystallization below 65 °C is considerably milder and the conductivity at 30 °C was ca. 100 times higher than the plain PEO–LiClO4 systems. A significant effect of the residual methanol on the ionic conductivity of our [(8/2) PEO/PEI]10–LiClO4 samples was recognized, which necessitated our previously reported log σ vs. 1000/T curve to be corrected downward by ca. half an order of magnitude. [Copyright &y& Elsevier]

In order to study biological properties of the corticospinal tract, we have reconstructed this system in an in vitro slice culture preparation. Motor cortex and spinal cord slices, prepared from newborn rats, were co-cultured on pored membranes for 16–24 days. Anterograde labeling with biocytin showed that substantial neural connections had formed between the cortex and spinal cord slices. Retrograde labeling with horseradish peroxidase or 1,1′-dioctadecyl-3,3,3′,3′-tetramethylindocarbocyanine perchlorate demonstrated that the parent cells were located primarily in the deeper layer of the cortex, as is found in vivo. Stimulation of the deep layer of the cortex elicited extracellular postsynaptic responses and intracellular excitatory postsynaptic potentials (EPSPs) in the co-cultured spinal cord that were mediated by the 1-amino-3-hydroxy-5-methyl-4-isoxazolepropionate/ kainate-type glutamate receptor. The intracellular injection of biocytin after EPSPs were recorded showed that one-third of these cells were large stellate cells, which are thought to be motoneurons, while a large portion of the remaining labeled cells were bipolar cells of smaller sizes.Using this reconstructed in vitro preparation, we recorded field EPSPs (fEPSPs) along a 100-μm-interval lattice in the spinal gray matter, which allowed the quantitative evaluation of synapse formation. The fEPSP amplitudes were more than two-fold larger when the forelimb cortex was co-cultured with cervical cord rather than lumbar cord. However, hindlimb cortex did not show this preference. The fEPSP amplitudes were more than twice as large when the dorsal side of the spinal cord was adjacent to the cortex than the ventral side.In summary, we have reconstructed the corticospinal projection and synapses in vitro using cortical and spinal explants. This system allows for an efficient quantitative evaluation of synapse formation and for studies of postsynaptic cells. Our results suggest that synapse formation shows preferences along and perpendicular to the neuraxis of the spinal cord. [Copyright &y& Elsevier]

Examines the UT-3 thermochemical hydrogen producing cycle. Utilization of solid and gas reactants; Description of solar thermochemical process; Elimination of heat exchangers; Comparison of the cost of solar hydrogen with other processes operating in cyclic manner.