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Emitting CdTe nanocrystals (NCs) were embedded in pure glass matrices (Si1-xZrxO2, x≤0.15) using a controlled sol–gel method, where the pre-hydrolyzed condition, the molar ratio of Zr/Si, the gelation time, the pH, and the amount of alcohol were judiciously optimized considering the surface condition of the NCs and the mechanism of the glass formation. As a result, the prepared glass phosphor exhibited high photoluminescence efficiencies (40% for green and 60% for red when Zr/Si was 5–10%) by retaining their initial values as in CdTe colloidal solution. To our knowledge, these values are the highest among those ever obtained for any solid matrices containing NCs. Because of the existence of Zr, the prepared glasses exhibit much better resistance against the ambient atmosphere, heat-treatment, and boiling water compared with pure silica glass (x=0) or the glass prepared from our other methods using a silane coupling agent. Thus, the obtained glass is promising for applications such as optical devices. [ABSTRACT FROM AUTHOR]

Background: Insight into the mechanisms of organ engraftment and acquired tolerance has made it possible to facilitate these mechanisms, by tailoring the timing and dosage of immunosuppression in accordance with two therapeutic principles: recipient pretreatment, and minimum use of post-transplant immunosuppression. We aimed to apply these principles in recipients of renal and extrarenal organ transplants.Methods: 82 patients awaiting kidney, liver, pancreas, or intestinal transplantation were pretreated with about 5 mg/kg of a broadly reacting rabbit antithymocyte globulin during several hours. Post-transplant immunosuppression was restricted to tacrolimus unless additional drugs were needed to treat breakthrough rejection. After 4 months, patients on tacrolimus monotherapy were considered for dose-spacing to every other day or longer intervals.Findings: We frequently saw evidence of immune activation in graft biopsy samples, but unless this was associated with graft dysfunction or serious immune destruction, treatment usually was not intensified. Immunosuppression-related morbidity was virtually eliminated. 78 (95%) of 82 patients survived at 1 year and at 13-18 months. Graft survival was 73 (89%) of 82 at 1 year and 72 (88%) of 82 at 13-18 months. Of the 72 recipients with surviving grafts, 43 are on spaced doses of tacrolimus monotherapy: every other day (n=6), three times per week (11), twice per week (15), or once per week (11).Interpretation: The striking ability to wean immunosuppression in these recipients indicates variable induction of tolerance. The simple therapeutic principles are neither drug-specific nor organ-specific. Systematic application of these principles should allow improvements in quality of life and long-term survival after organ transplantation. [ABSTRACT FROM AUTHOR]

Photochemical hole-burning in sodium-borate glass (35Na2O–65B2O3) was investigated as a function of doped Eu-ion concentration from 0.1 to 5 mol% both at room temperature and 12 K. In our preparation, 50–70% of Eu3+ was reduced to Eu2+. As the concentration of Eu ion exceeded 1 mol%, the fluorescence was quenched, and meanwhile the photochemical hole started burning. The spectral hole was most efficiently burnt at concentrations between 2 and 3 mol% at room temperature. Low temperature experiment showed that there are three kinds of processes for the hole formation. One is a transient process relaxed within 1–2 min. Another is observed only at low temperatures. The third one is observed persistently even at room temperature. The extent of these components depends on Eu-ion concentration. In view of these concentration dependences, the suggested mechanism of room temperature hole-burning is an energy or electron transfer between Eu3+ and Eu2+. Defect centers created by reduction process of the glass may play a role to help this transfer. [Copyright &y& Elsevier]

ZnSe nanocrystals are prepared in water by a wet chemistry method. By selecting an appropriate pH value and surface-capping agents, a whitish blue fluorescence peaking at 470 nm is observed under UV irradiation. The intensity of this fluorescence increases dramatically under reflux and saturates after ∼40 hrs. The final mean size of the ZnSe nanocrystals measured by transmission electron microscopy is about 2 nm in diameter. The quantum efficiency of the fluorescence from the final solution is estimated to be ∼1%, although the preparation conditions have not yet been completely optimized. These properties are discussed in comparison with those of similarly prepared CdTe and differently prepared ZnSe nanocrystals. [ABSTRACT FROM AUTHOR]

SUMMARY:The productive structure and productivity of a Sargassum macrocarpum C. Agardh population were studied from June 1993 to July 1994 in Fukawa Bay facing the Sea of Japan, Yamaguchi Prefecture. S. macrocarpum formed a dense population at a depth of 8 m in the study area. Using the stratified clip technique, monthly changes in the productive structure from 1993 to 1994 were clarified. The dry weight of leaves and main branches increased with the elongation of branches. Thalli in the middle to high stratum began to bear receptacles from March 1994 and the dry weight of receptacles was approximately one-third of the standing crop in June. The loss of leaves increased from April to June 1994, and the loss of main branches and receptacles from June to July 1994. Productivity of branches and receptacles reached maxima of 4.67 g dry wt/m2 per day from February to March and 5.33 g dry wt/m2 per day from April to May, respectively. Productivity of the leaves, however, was almost constant at approximately 2 g dry wt/m2 per day from July 1993 to March 1994. Therefore, maximum productivity of the S. macrocarpum population of 7.17 g dry wt/m2 per day occurred from February to March. Annual net production of newly sprouting branches in June 1993 was 1600.1 g dry wt/m2 per year based on the summation method, which was calculated from the monthly changes in the productive structure. [ABSTRACT FROM AUTHOR]

An immunohistochemical survey of the distribution of keratin was studied in chemically induced carcinomas of the submandibular glands of mice. Initial signs of premalignant changes were degranulation of granular convoluted tubule cells and deposition of keratin protein in small limited areas of the degranulated cells. There was a gradual increase in the area showing keratin staining in altered tubule cells. Duct-like and cystic structures stained intensely for keratin, as did squamous metaplastic epithelial cells. Induced carcinomas were variably keratinized. Basal layers of cells of squamous-cells carcinomas displayed weak keratin staining, and spinous tumor cells and parakeratotic tumor cells showed somewhat increased levels of keratin staining. Some desquamated keratotic tumor cells stained intensely for keratin. Just as the localization of epidermal and nerve growth factors and lectin-binding histochemistry have been used in studying tumorigenesis in the mouse submandibular gland, immunohistochemically detected keratin proved to be a useful marker of tumor cells of ductal segment origin. [ABSTRACT FROM AUTHOR]

Complex carbohydrates in premalignant lesions of mouse submandibular gland tumors were examined by the lectin-peroxidase conjugate method. Peroxidase-conjugated lectins of PNA, RCA-1, DBA, SBA, UEA-1 and WGA were used to detect specific sugar residues of complex carbohydrates in premalignant lesions during experimental carcinogenesis. Marked reduction of PNA and SBA bindings occurred in duct-like structures and cystic lesions which were transformed from granular convoluted tubule cells. Premalignant lesions bound slightly to PNA, RCA-1, DBA, SBA as compared to those of duct-like structure and cystic epithelia. [ABSTRACT FROM AUTHOR]

Focuses on a method using a conventional melt-quenching KCI:Eu2+ films for photostimulated luminescence applications. Details on the intense photostimulated luminescence (PLS) yielded by these films . Information on the starting chemicals used; Discussion on the X-ray diffraction patterns of melt-quenched films; Examination of the X-band EPR spectra of KCI:Eu2+.

Objective To investigate processes in pain perception and pathophysiology of insensitivity to pain by using laser-evoked potential (LEP) and positron emission tomography during painful stimulation (pain PET). Methods We investigated a 29-year-old male patient with familial spastic paraparesis who developed insensitivity to pain around 15-year-old. He was mentally retarded but not autistic or depressive. We recorded LEP and regional cerebral blood flow using pain PET of the patient during selective painful stimulation to left hand dorsum delivered by a CO 2 laser. Results The patient described that he could feel the painful stimulation as being touched but they were not painful or hot, while his skin showed burn. LEP elicited cortical potential negative peak latency of 240–284 ms maximum in Cz in normal amplitude and latency. Pain PET evoked activation in the right parietal operculum and posterior insula, the left insula, and bilateral parietal lobes, however, prefrontal area and anterior cingulate cortex were not activated. Conclusions The current investigation suggests that insensitivity to pain in this patient can be caused by abnormal processing of pain perception in brain. Key message Insensitivity to pain can be attributed to not only peripheral nerve but also brain. [ABSTRACT FROM AUTHOR]

Aim: To examine the effects of low-volume muscle endurance training on muscle oxidative capacity, endurance and strength of the forearm muscle during 21-day forearm immobilization (IMM-21d). Methods: The non-dominant arm ( n = 15) was immobilized for 21 days with a cast and assigned to an immobilization-only group (Imm-group; n = 7) or an immobilization with training group (Imm+Tr-group; n = 8). Training comprised dynamic handgrip exercise at 30% of pre-intervention maximal voluntary contraction (MVC) at 1 Hz until exhaustion, twice a week during the immobilization period. The duration of each exercise session was 51.7 ± 3.4 s (mean ± SE). Muscle oxidative capacity was evaluated by the time constant for phosphocreatine recovery ( τoffPCr) after a submaximal handgrip exercise using 31phosphorus-magnetic resonance spectroscopy. An endurance test was performed at 30% of pre-intervention MVC, at 1 Hz, until exhaustion. Results: τoffPCr was significantly prolonged in the Imm-group after 21 days (42.0 ± 2.8 and 64.2 ± 5.1 s, pre- and post-intervention respectively; P < 0.01) but did not change for the Imm+Tr-group (50.3 ± 3.0 and 48.8 ± 5.0 s, ns). Endurance decreased significantly for the Imm-group (55.1 ± 5.1 and 44.7 ± 4.6 s, P < 0.05) but did not change for the Imm+Tr-group (47.9 ± 3.0 and 51.7 ± 4.0 s, ns). MVC decreased similarly in both groups ( P < 0.01). Conclusions: Twice-weekly muscle endurance training sessions, each lasting approx. 50 s, effectively prevented a decrease in muscle oxidative capacity and endurance; however, there was no effect on MVC decline with IMM-21d. [ABSTRACT FROM AUTHOR]

We describe a facile sol–gel process using a silane coupling agent to encapsulate photoluminescent CdTe nanocrystals. An amino-containing matrix and CdTe NCs stabilized by thioglycolic acid were found to be the best combination to prepare the glass because of the interaction between amino and carboxyl groups. The process of synthesis was optimized to prevent nanocrystals from agglomerating. The optical absorption and luminescent spectra of CdTe nanocrystals remained unchanged after being embedded into the glass matrix. Multi-color nanocrystals embedded in glass had the photoluminescence efficiencies up to 41%, which were similar to those of starting nanocrystals in solution. The nanoparticles embedded in glass had excellent stability over time and with heat treatment. [Copyright &y& Elsevier]

PURPOSE: Although it is well known that immobilization causes muscle atrophy, most immobilization models have examined lower limbs, and little is known about the forearm. The purpose of this study was to determine whether forearm immobilization produces changes in muscle morphology and function. METHODS: Six healthy males (age: 21.5 +/- 1.4, mean +/- SD) participated in this study. The nondominant arm was immobilized with a cast (CAST) for 21 d, and the dominant arm was measured as the control (CONT). The forearm cross-sectional area (CSA) and circumference were measured as muscle morphology. Maximum grip strength, forearm muscle oxidative capacity, and dynamic grip endurance were measured as muscle function. Magnetic resonance (MR) imaging was used to measure CSA, and 31phosphorus MR spectroscopy was used to measure time constant (Tc) for phosphocreatine (PCr) recovery after submaximal exercise (PCr-Tc). Grip endurance was expressed by the number of handgrip contractions at 30% maximum grip strength load. All measurements were taken before and after the immobilization. RESULTS: After the 21-d forearm immobilization, no changes were seen for each measurement in CONT. CSA and the circumference showed no significant changes in CAST. However, maximum grip strength decreased by 18% (P < 0.05), PCr-Tc was prolonged by 45% (P < 0.05), and the grip endurance at the absolute load was reduced by 19% (P < 0.05) for CAST. CONCLUSION: In this model, 21-d forearm immobilization caused no significant changes in forearm muscle morphology, but the muscle function showed remarkable deterioration ranging from 18 to 45%. [ABSTRACT FROM AUTHOR]

Peroxidase-conjugated lectins were used for the histochemical detection of carbohydrates in experimental carcinomas of mouse submandibular glands. Induced carcinomas. 43 lesions from 25 cases, were examined histochemically with galactose-binding lectins (PNA and RCA-I) N-acetyl-galactosamine-binding lectins (DBA and SBA) a fucose-binding lectin(UEA-I), and a N-acetyl-glucosaminebinding lectin (WGA). In non- or slightly keratinized squamous-cell carcinomas. the lectin binding of PNA, RCA-1, DBA, SBA, and WGA was weak in minor epithelia, and UEA-1 binding was slight. In highly keratinized squamous-cell carcinomas, lectin binding was increased in minor epithelia, but no reaction was noted in completely keratinized regions. Desquamated materials in lumens of tumors gave an intense stain with lectins. Stromal connective tissue, including collagen fibers and basement membranes stained intensely. Lectin binding lo submandibular carcinomas was different from binding to granular convoluted tubules and the striated ducts of the normal submandibular gland. [ABSTRACT FROM AUTHOR]

Histopathologic observations of 9,10-dimethyl-l,2-benzanthracene (DMBA)-induced tumors in the mouse submandibular glands are reported using cryoprobe treatment. The experimental animals were divided into 2 groups; one received a carcinogen injection into the normal submandibular gland, and the other was injected with DMBA on the 14ih day following cryosurgery of the gland using a -60°C cryoprobe. Pathologic findings were classified as prernalignant lesions or squamous-cell carcinomas with varying degrees of keratinization, fibrosarcoma and mixed careinnonma. There was also one case each of malignant plcomorphic adenoma and cystic adenoma. tumor incidence was nearly the same in the 2 groups. Most of the carcinomas and sarcomas in the submandibular gland were induced during the 12th and 17th weeks. DMBA application during the proliferating stage which followed the cryosurgery did not enhance epithelial-tumor induction. During submandibular gland carcinogenesis, alterations in the granular convoluted tubule cells suggests they were the initial target cells undergoing malignant transformation. Squamous-cell carcinomas with varying degrees of keratinization were induced following squamous metaplasia in duct-like structures or multicyslic lesions. [ABSTRACT FROM AUTHOR]

Autoimmune thyroid disease was induced in female PVG/c rats by neonatal thymectomy, followed by sublethal, whole body x-irradiation. Disease development, assessed by histological evidence of lymphoeytic thyrolditis and circulating levels of anti-thyroglobulin antibodies, was reduced significantly by a 3-week course of FK 506 (0.5 or 15 mg/kg per day) commencing after the detection of autoantibody production. Thyroid-infiltrating mononuclear cells (MNC) in untreated rats stained predominantly forCD4+ and MHC class II antigen whieh was expressed widely on dendritic cells. Fewer infiltrating cells expressed TCR α/β, CD5, CD8 or LFA-1/β. Intercellular adhesion molecule-1 (ICAM-l) was observed on MNC, vascular endothelial cells and a minoritiy of residual thyroid epithelial cells. FK 506 administration reduced markedly the incidence of infiltrating TCRα/β+, CD5+, CD4+, CD8+, and LFA-lβ + cells and the expression both of MHC class II antigens and ICAM-1 on MNC, endothelial cells and thyrocytes. Compared with normal PVG/c rats, there were reduced incidenees of CD4+ CD8+ and CD4+ CD8+ lymphocytes and an elevation in the CD4+/CD8+ cell ratio in the spleens of animals with autoimmune thyroiditis. These changes were partially reversed by FK 506. Systemic drug levels estimated by enzyme immunosorbent assay were in excess of those known to blockade cytokine production by CD4+ T lymphocytes in vitro and some evidence of minor renal dysfunction was observed. The results are consistent with a therapeutic effect of FK 506 mediated via interference with CD4+ T lymphocyte function and adhesion molecule-dependent cytotoxic effector mechanisms. [ABSTRACT FROM AUTHOR]

Aim: To examine the blood flow (BF) response in the lower abdomen (LAB) in recovery following upright cycling exercise at three levels of relative maximum pulmonary oxygen consumption () and the relationship of BFLAB to heart rate (HR) and target intensity. Methods: For 11 healthy subjects, BF (Doppler ultrasound) in the upper abdominal aorta (Ao) above the coeliac trunk and in the right femoral artery (RFA) was measured repeatedly for 720 s after the end of cycling exercises at target intensities of 30%, 50% and 85%, respectively. Blood flow in the lower abdomen (BFLAB) can be measured by subtracting bilateral BFFAs (≈twofolds of BFRFA) from BFAo. Change in BFLAB (or BFLAB volume) at any point was evaluated by difference between change in BFAo and in BFFAs. Heart rate and blood pressure were also measured. Results: At 85%, significant reduction in BFLAB by approx. 89% was shown at 90 s and remained until 360 s. At 50%, reduction in BFLAB by approx. 33% was found at 90 s although it returned to pre-exercise value at 120 s. On the contrary at 30%, BFLAB showed a light increase (<20%) below 70 bpm of HR. There was a close negative relationship ( P < 0.05) between change in BFLAB and recovery HR, as well as between change in BFLAB volume and both recovery HR and %. Conclusion: This study suggests that the lower abdominal BF in recovery may be influenced by sympathetic-vagus control, and dynamics of BFLAB may be closely related to the level of relative exercise intensities. [ABSTRACT FROM AUTHOR]

Abstract: Post-preparative white light irradiation causes thiol-stabilized ZnSe nanocrystals (NCs) dispersed in water to become photoluminescent. The reported photoluminescence efficiency and peak wavelength are 25–30% and ca. 390nm, respectively. We have found that through a judicious choice of irradiation conditions, especially the irradiation wavelength and intensity, the solution pH, and the NC concentration, we can increase the emission efficiency to 50% with a peak wavelength in the visible region (405–435nm). These improvements were achieved through efficient formation of a thick ZnS shell (more than 1nm) around the ZnSe core (2–3nm in diameter) enabled by the generation of sulfur ions at an appropriate speed via the photodecomposition of a thiol stabilizer. To make them more suitable for application, we then incorporated the prepared NCs into a glass matrix, taking advantage of their water solubility through a sol–gel method. The prepared glass had an efficiency of more than 20% without deterioration of the photoluminescent spectral shape of the initial solution. [Copyright &y& Elsevier]

The lectin, Concanavalin A(Con A) has been used to localize specific sugar residues (D-glucose, D-mannose and D-fructose) in premalignant lesions and squamous-cell carcinomas induced following cryosurgery of the mouse submandibular gland. The original Con A-horseradish peroxidase (HRP) technique as well as its combination with periodate oxidation and subsequent reduction by borohydrate were used to compare the epithelial elements during submandibular gland carcinogenesis. Granules in the granular convoluted tubule cells which were weakly reactive to the Con A-HRP method were not present in the premalignant duct like structures. The epithelium of premalignant lesions, duct-like structures, multicystic lesions, and squamous-cell carcinomas were positive for the cell-surface and intercellular substances; and basement membranes and stromal fibers were also positive. The results indicated that throughout malignant transformation of the ductal segments, premalignant epithelia lost Con A-HRP-staining granules and that Con A-binding patterns in induced squamous-cell carcinomas were similar to those found in squamous-cell epithelium. [ABSTRACT FROM AUTHOR]

Background: Liver transplantation for type IV glycogen storage disease (branching-enzyme deficiency) results in the resorption of extrahepatic deposits of amylopectin, but the mechanism of resorption is not known.Methods: We studied two patients with type IV glycogen storage disease 37 and 91 months after liver transplantation and a third patient with lysosomal glucocerebrosidase deficiency (type 1 Gaucher's disease), in whom tissue glucocerebroside deposition had decreased 26 months after liver replacement, to determine whether the migration of cells from the allograft (microchimerism) could explain the improved metabolism of enzyme-deficient tissues in the recipient. Samples of blood and biopsy specimens of the skin, lymph nodes, heart, bone marrow, or intestine were examined immunocytochemically with the use of donor-specific monoclonal anti-HLA antibodies and the polymerase chain reaction, with preliminary amplification specific to donor alleles of the gene for the beta chain of HLA-DR molecules, followed by hybridization with allele-specific oligonucleotide probes.Results: Histopathological examination revealed that the cardiac deposits of amylopectin in the patients with glycogen storage disease and the lymph-node deposits of glucocerebroside in the patient with Gaucher's disease were dramatically reduced after transplantation. Immunocytochemical analysis showed cells containing the HLA phenotypes of the donor in the heart and skin of the patients with glycogen storage disease and in the lymph nodes, but not the skin, of the patient with Gaucher's disease. Polymerase-chain-reaction analysis demonstrated donor HLA-DR DNA in the heart of both patients with glycogen storage disease, in the skin of one of them, and in the skin, intestine, blood, and bone marrow of the patient with Gaucher's disease.Conclusions: Systemic microchimerism occurs after liver allotransplantation and can ameliorate pancellular enzyme deficiencies. [ABSTRACT FROM AUTHOR]

Presents research which traced the origin of repopulating liver cells in rats following cross-sex or cross-strain bone marrow and whole liver transplantation. Development of lineages in bone marrow stem cells; Treatment of the rats; Methods used for identification of liver cells of bone marrow origin; Proportion of regenerated hepatic cells shown to be donor-derived; Epithelial cell lineage capability of stem cells.