Radiophotoluminescence phenomenon in copper-doped aluminoborosilicate glass

Radiophotoluminescence phenomena have been widely investigated on various types of materials for dosimetry applications. We report that an aluminoborosilicate glass containing 0.005 mol% copper exhibits intense photoluminescence in the visible region induced by X-ray and γ-ray irradiation. The luminescence is assigned to the 3d⁹4s¹ → 3d¹⁰ transition of Cu⁺. The proportionality of the intensity of the induced photoluminescence to the irradiation dose was confirmed up to 0.5 kGy using ⁶⁰Co γ-ray irradiation. Based on the spectroscopic results, a potential mechanism was proposed for the enhancement of the photoluminescence. The exposure to the ionizing radiation generates electron-hole pairs in the glass, and the electrons are subsequently captured by the Cu²⁺ ions, which are converted to Cu⁺ and emit the luminescence. For the glass containing 0.01 mol% copper, the pronounced enhancement of the photoluminescence was not observed because the reverse reaction, ie, the capture of the holes by the Cu⁺ ions, becomes prominent. The photoluminescence induced by the irradiation was stably observed for the glasses kept at room temperature and even for the glasses heat-treated at 150°C. However, the induced photoluminescence could be eliminated by the heat treatment at a temperature at 500°C, and the glass returned to the initial pre-irradiation state. The Cu-doped aluminoborosilicate glass is a potential candidate for use in dosimetry applications.     

New design of hybrid-type self-bearing motor for small, high-speed spindle

A new structure of hybrid (HB)-type self-bearing motor is proposed for miniature spindle motors. The proposed design combines the HB-type self-bearing motor and HB active magnetic bearing in the common stator and rotor pair to generate large radial forces. First, the principle and theoretical background are introduced. Then, the air gap flux is analyzed by the finite element method, and radial forces for the proposed and standard-type HB self-bearing motors are compared. Finally, experiments are conducted to confirm the performance of the proposed motor. The motor can run at relatively high rotating speed with relatively high torque compared with its small size. The levitation is very stable and the motor indicates good performance for practical application.     

Sucralfate attenuates gastric mucosal lesions and increased vascular permeability induced by ischaemia and reperfusion in rats

Recent evidence suggests that oxygen-derived free radicals are involved in mediating gastric microvascular and parenchymal cell injuries induced by ischaemia and reperfusion. Therefore, the effect of the locally acting anti-ulcer drug, sucralfate, was studied on ischaemia and reperfusion (e.g. induced gastric lesions, intraluminal bleeding, changes in vascular permeability and non-protein sulfhydryl levels in the rat stomach). Allopurinol was used as a known standard antioxidant drug. Rats were subjected to 30 min of gastric ischaemia in the presence of 100 mmol/L hydrochloric acid and reperfusion periods of 15, 30 or 60 min duration. The gastric lesions were assessed microscopically under an inverted microscope. The vascular permeability was quantified by measuring the extravasated Evans blue in the stomach. There were significantly greater numbers of gastric lesions, intraluminal bleeding and leakage of Evans blue during all reperfusion periods as compared with those of ischaemia, with maximum effects occurring at 60 min following reperfusion. Pretreatment with sucralfate (31.25-250 mg/kg, p.o.) or allopurinol (12.5-50 mg/kg, i.p.) 30 min before the procedure, dose-dependently reduced the gastric lesions, intraluminal bleeding, and decreased the vascular permeability induced by ischaemia and reperfusion. Furthermore, sucralfate dose-dependently reverses the ischaemia and reperfusion-induced depletion of mucosal non-protein sulfhydryl levels and inhibited the superoxide radical production in both cell-free xanthine-xanthine oxidase and in the stimulated polymorphonuclear cellular systems. These results suggest that the protection produced by sucralfate against gastric injury may be due to its antioxidant effects.     

Bronchiolo-alveolar cell carcinoma with apparent response to chemotherapy to anti-tuberculosis

Pigmented vulvar lesions were observed in a child during a sexual abuse evaluation. Gross examination of the lesions appeared most consistent with bowenoid papulosis; however, biopsy confirmed the lesions to be pigmented apocrine hamartomas. To our knowledge, these rare and benign tumors have never been described as pigmented, but should be added to the differential diagnosis of pigmented vulvar lesions.     

Characterization of pigmented granules in minocycline-induced cutaneous pigmentation: observations using fluorescence microscopy and high-performance liquid chromatography

Ambiguous abdominal situs, asplenia/polysplenia and severe cardiac malformations characterize heterotaxy in humans. These anomalies result from the inability of the developing embryo to establish normal left-right asymmetry. We have studied an interesting family in which the heterotaxy phenotype segregates as an X-linked recessive trait. In order to map the heterotaxy locus (HTX), we have analysed 39 family members using highly-polymorphic microsatellite markers from the X chromosome. One of these markers, DXS994, shows no recombination with the disease locus in 20 informative meioses. Linkage analysis results in a maximum lod score of 6.37. Current genetic and physical mapping data assign the order of loci in Xq24-q27.1 as cen-DXS1001-(DXS994, HTX)-DXS984-tel. These results establish the first mapping assignment of situs abnormalities in humans.     

Anomalies of the tracheobronchial tree in patients with esophageal atresia

Bone marrow examination revealed a lipid-laden histiocytosis in seven patients undergoing long-term total parenteral nutrition necessitated by extensive short-bowel surgical resection. Clinical abnormalities occurred during this treatment which required bone marrow examination. These included hepatosplenomegaly and peripheral blood cytopenia; the median time to the detection of these abnormalities was 64 months. The most striking change within the bone marrow was the presence of many pigment-laden histiocytes which had the typical morphology of sea-blue histiocytes seen in the so-called idiopathic sea-blue histiocyte syndrome. The occurrence of sea-blue histiocytosis in the bone marrow in association with long-term parenteral nutrition for short-bowel syndrome has not, to our knowledge, been reported previously and should now be considered in the differential diagnosis of bone marrow sea-blue histiocytosis.     

Influence of lead on metabolism of vitamins B group in alimentary iron deficient rats

Gamma delta T-Cells represent a minor subpopulation of T-lymphocytes in man and their role in normal and diseased human skin is unknown. This article is a comprehensive review of T-lymphocytes bearing the gamma delta T-cell receptor in normal and pathological human skin. Firstly, we have documented the occurrence of gamma delta T-cells in normal skin and in a range of reactive and malignant skin conditions. We have then discussed the experimental findings regarding the repertoire used by gamma delta T-cells in normal human skin and in cutaneous disorders with an increased percentage of gamma delta T-cells.     

CT of appendicitis in children

PURPOSE: Our goal was to review the CT findings and to help define the role of CT in the evaluation of appendicitis in children. METHOD: Of 730 children with surgically proven appendicitis, 22 underwent preoperative CT evaluation. Their CT scans and operative and pathology records were retrospectively reviewed. The CT scans were evaluated for appendiceal wall thickness, diameter, and location, appendicoliths, pericecal inflammation, phlegmon, abscess, free fluid, small bowel dilatation, and bowel wall thickening. Criteria for diagnosing appendicitis were (a) appendiceal wall thickening (> 1 mm) or (b) presence of abscess, phlegmon, or pericecal inflammation associated with appendicolith(s). Prospective reports of ultrasound examinations performed within 2 days of the CT scans were available in 14 children and were correlated with the CT findings. RESULTS: An abnormally thickened appendix, with a diameter ranging from 9 to 18 mm, was seen in four children. Three appendices were retrocecal and one was near the cecal tip, anterior to the iliac vessels. Appendicoliths were present in 10 children, multiple in 1. Abscesses were seen in 13 of 22 children, multiple in 5. Phlegmon was seen in five children and pericecal inflammation in two. Bowel wall thickening was present in seven children and small bowel dilatation was noted in six. Other findings included free fluid, hydronephrosis, thickening of urinary bladder wall, air in the uterus and vagina, adenopathy, and thickening of the abdominal wall musculature. CT was diagnostic of appendicitis in 11 of 22 children (50%). In 14 children with both ultrasound and CT studies, CT was slightly better in diagnosing appendicitis and visualizing the abnormal appendix and was superior in defining the presence and extent of abscess and inflammation in 9 of 14 children. CONCLUSION: CT is a useful adjunct in diagnosing appendicitis in children, with a major role in cases of complicated appendicitis.