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Myelin is essential to neuronal health and CNS function, and oligodendrocytes (OLs) undergo a complex process of cytoskeletal remodeling to form compact myelin sheaths. We previously discovered that a formin protein, Dishevelled associated activator of morphogenesis 2 (Daam2), suppresses OL differentiation through Wnt signaling; however, its role in cytoskeletal control remains unknown. To investigate this, we used OL-specific Daam2 conditional knockout (Daam2 cKO) mice of either sex and found myelin decompaction during an active period of myelination in postnatal development and motor coordination deficits in adulthood. Using primary OL cultures, we found Daam2-depleted OLs showed morphologic dysregulation during differentiation, suggesting that Daam2 regulates the OL cytoskeleton. In vivo screening identified the actin regulators Rac1 and Gelsolin as possible effectors in Daam2-deficient OL cytoskeletal regulation. Using gain-of-function and loss-of-function (LOF) experiments in primary OLs, we found that Rac1 and Gelsolin operate downstream of Daam2 in OL differentiation, with Gelsolin and Daam2 promoting and inhibiting membrane spreading during late differentiation, respectively. In vivo experiments using Daam2 cKO mice revealed increased protein levels of Gelsolin in the developing white matter with no change in RNA levels, suggesting that Daam2 acts in a posttranslational manner to suppress Gelsolin levels. In vitro biochemical studies show Daam2 induces Gelsolin ubiquitination and degradation in OLs. Together, our studies show Daam2 is essential for formation of functional myelin through modulation of Gelsolin levels to regulate the OL cytoskeleton. These findings further demonstrate the critical role of cytoskeletal dynamics in myelination and reveal novel avenues for treatment of a variety of white matter diseases. [ABSTRACT FROM AUTHOR]

Abstract: The electrolytic production of Mg from MgO was experimentally and theoretically investigated near 1550 K. The experimental work was carried out in a SiC electrolytic cell housed in a 10 kW solar receiver that was located at the focal point of a concentrating solar furnace. The oxide was dissolved in either CaF2 or MgF2. The cathode was Mo and the anode was either Pt or Cgraphite. Mg evolved as a gas, was quenched on cooling coils at the exit of the reactor and was collected for analysis. A thermodynamic cycle study indicates that the ideal thermal efficiency for the solar process is 35 percent for an inert anode and 39 percent for a carbon anode. Experimental results from both current-cell potential traces and X-ray diffraction verify the successful electrolysis of MgO and the production of Mg. The experimental decomposition potential of the oxide was near the expected thermodynamic value. As expected, the experimental decomposition potential was reduced when carbon replaced the inert anode. In the experiment with Pt as the anode and MgF2 as the solvent, a current efficiency of 14 percent was measured. [Copyright &y& Elsevier]

This descriptive study of practice barriers compared the perceptions of 67 psychiatric/mental health clinical nurse specialists (PMH-CNSs) with those of 767 nurse practitioners (NPs) in a single state. In addition, it contrasted the barriers identified by the rural and urban PMH-CNS study participants ( n = 14 and 53, respectively). Though all participants found the practice climate moderately restrictive on a 5-point Likert scale (1 = very restrictive to 5 = not restrictive), the PMH-CNSs found the practice environment significantly more restrictive than the NPs (3.13 versus 3.61, p [ABSTRACT FROM AUTHOR]

During the last years allergenic substances in food have gained more and more attention. Stricter rules for a peanut free food labelling demand a peanut contamination less than 5 ppm. The maintenance of a high quality of food products with regards to allergenic exposure is preferable warranted with rapid tests that can be utilized as an aid for suppliers to control raw materials, to avoid cross contamination during production and to check the final products. A rapid sandwich peanut ELISA was developed, which covers a measuring range of 2.5–20 ppm peanut (detection limit of 1.5 ppm). This test was successfully evaluated in an independent study under the supervision of the AOAC Research Institute, getting the AOAC certificate No. 030404. In-house validation and independent validation data demonstrate the reliability, accuracy and precision of the test. [ABSTRACT FROM AUTHOR]

Background: RIDASCREEN® Histamine (enzymatic) is an enzymatic test kit for quantification of histamine in fresh fish, canned fish, fish meal, cheese, and wine. Methods: Fish products are extracted with boiling water, while cheese is extracted with water, and the extract is treated with perchloric acid/potassium hydroxyde. Wine is extracted with the reagents of RIDA® Sample Decolorant kit to eliminate color pigments and interfering compounds. The enzymatic determination is based on histamine dehydrogenase, which catalyzes the oxidative deamidation of histamine in the presence of an electron carrier that converts a dye to a color product. The resulting color intensity is directly proportional to histamine concentration and is measured at 450 nm. The substrates are coated on the microtiter plate. Results: The linear range is from 1 to 20 mg/L in the extract. LOQs are 2 mg/kg for fresh fish, canned fish, and cheese, 1.4 mg/L in wine, and 10 mg/kg for fish meal. The linear range is from 5 to 100 mg/kg for fish products and cheese, 3.6 to 72 mg/L for wine, and 25 to 500 mg/kg for fish meal. Recovery and precision are very good for all matrices, and comparisons with HPLC reference methods revealed that the method also delivers true results for fish products and wine. Agmatine shows a low side activity of around 0.75% at 10 g/kg. Possible interfering substances are ascorbic acid (more than 250 mg/L in wine or 250 mg/kg in fish). A special sample preparation to deplete ascorbic acid from fresh fish is described. [ABSTRACT FROM AUTHOR]

The solar thermal electrolytic production of Zn from ZnO was studied in the temperature range of 1275-1500 K in a cavity-solar receiver located at the focal point of a concentrating solar furnace. This study establishes how cathode material, solvent, current levels, and operating temperature influence the electrolytic cell's performance. For a nominal current density of 0.1 A cm-2 at temperatures from 1275 to 1425 K, we found that our performance parameters, the back work ratio and substituted-solar fraction, are within 25% and 20% of the ideal values, respectively. This behavior was true whether the cathode was Mo or W and whether the electrolyte was pure cryolite or a 35 mol. % cryolite-CaF2 mixture. When the electrolytes were cryolite-CaF2 mixtures in the temperature range of 1275-1425 K, there was no measurable difference in the performance, but at 1500 K with a MgF2 electrolyte, the performance dropped significantly. We have some evidence that the performance of the cell is better at current densities above 0.1 A cm-2 when the cathode is Mo as opposed to W. Furthermore, the difference in the performance values can be attributed to higher kinetic over voltages associated with W versus Mo as a cathode. Our data also suggest that kinetic over voltages increase as the operating temperature increases. The experimental evidence suggests the reaction mechanism at the cathode for ZnO in cryolite involves a reaction between Na+ and ZnF2, and the anode reaction involves a reaction between the anions Al2OF62 - and ZnO22-. Both Mo and W worked as cathode materials, but both the Mo and the W became brittle. Pt worked well as an anode without showing any evidence of degradation. Our SiC crucible may have suffered some carbothermic reaction with ZnO at temperatures exceeding 1275 K, with solvent mixtures of cryolite, CaF2, and MgF2. [ABSTRACT FROM AUTHOR]

Objective. We performed an outcome evaluation of the impact of public health preparedness training as a group comparison posttest design to determine the differences in the way individuals who had participated in training performed in a simulated emergency. Methods. The Experimental Group 1 included students who had graduated from or were currently enrolled in the bioterrorism and emergency readiness (BT/ER) curriculum at the University of Minnesota School of Public Health. The comparison groups included individuals who had access to the Internet and were aware of the 2006 online simulation Disaster in Franklin County: A Public Health Simulation. The evaluation process employed surveys and the gaming simulation as sources for primary data. Results. Participants in the BT/ER curriculum (p=0.0001) and other participants completing at least 45 hours of training in the past year (p=0.0001) demonstrated higher effectiveness scores (accuracy of chosen responses within the simulation) than participants who did not report significant amounts of training. Conclusions. This evaluation research demonstrated that training is significantly associated with better performance in a simulated emergency using gaming technology. [ABSTRACT FROM AUTHOR]

Abstract: The microwave spectra of the three singly substituted 13C isotopomers and 18O isotopomer of equatorial-trans cyclobutanol, c-C4H7OH, have been observed in natural abundance by a pulsed-jet Fourier transform microwave spectrometer. The fit for the normal species was improved from the previous study. The rotational constants for the α-13C, β-13C, γ-13C and 18O isotopic species were determined. The five quartic centrifugal distortion constants were determined for the first time. These experimental values are compared to those obtained from ab initio and density functional theory calculations. By utilizing the previously reported microwave rotational constants for the O–D species along with the 15 constants determined from this study combined with the structural parameters predicted from the MP2(full)/6-311+G(d,p) calculations, adjusted r 0 parameters have been obtained. The determined heavy atom distances in Å are: r 0(C1–C4,5)=1.547(3), r 0(C6–C4,5)=1.556(3), r 0(C–O)=1.412(3) Å and angles , and puckering angle τC6C5C4C1 =31.3(10)°. The parameters are compared to the similar ones for some other monosubstituted cyclobutanes as well as to those for cyclobutane. [Copyright &y& Elsevier]

Characterization of the molecular basis of tumor recognition by T cells has shown that major histocompatibility complex (MHC) class I molecules play a crucial role in presenting antigenic peptide epitopes to cytotoxic T lymphocytes. MHC class Ia downregulation has been repeatedly described on melanoma cells and is thought to be involved in the failure of the immune system to control tumor progression. Proper assembly of MHC class I molecules is dependent on several cofactors, e.g. the chaperones calnexin and calreticulin residing in the endoplasmic reticulum. Alterations in the expression of these chaperones may have important implications for MHC class I assembly, peptide loading, and presentation on the tumor cell surface and thus may contribute to the immune escape phenotype of tumor cells. In the present study, we compared melanoma lesions representing different stages of tumor progression with regard to the expression of calnexin and calreticulin in tumor cells by means of immunohistochemistry.Metastatic melanoma lesions exhibited significant downregulation of calnexin as compared to primary melanoma lesions. In contrast, chaperone calreticulin was expressed in melanoma cells of primary as well as of metastatic lesions. Our data suggest that chaperone-downregulation, particularly calnexin-downregulation, may contribute to the metastatic phenotype of melanoma cells in vivo. Consistently, conserved chaperone expression in metastatic melanoma lesions may be a useful criterion for selection of patients for treatment with T cell-based immunotherapies. [Copyright &y& Elsevier]

Tumor cells with alterations in the MHC class I peptide-loading complex are unable to load peptide antigens onto MHC class I molecules. These alterations result in destabilization of MHC class I expression on the tumor cell surface and thus play a critical role in escape from immunological recognition by the acquired cellular immune system. By forming physical links between class I heavy chains and TAP molecules, a component of the class I peptide-loading complex, tapasin, plays an important role in the assembly of MHC class I molecules with peptides in the endoplasmic reticulum. In the present study, we compared 104 human melanoma lesions representing different stages of tumor progression for their expression of tapasin in tumor cells by immunohistochemistry. Tapasin downregulation was significantly associated with tumor progression. Whereas 100% of melanomata in situ and 96.2% of primary melanomas with a Breslow index of ≤0.75 mm showed strong expression of tapasin, significant downregulation of tapasin was observed in 25% of primary melanomas with a Breslow index >0.75 mm as well as in 21.1% metastatic melanoma lesions. The downregulation of tapasin in advanced stages of human melanoma may reflect the accumulation of alterations in the antigen-presenting/processing machinery associated with neoplastic progression. These alterations may lead to failure of the acquired cellular immune system to control progression and metastatic spread of melanoma cells in vivo, and thus contribute to the immune escape phenotype of human melanoma cells. [ABSTRACT FROM AUTHOR]

Recently, expression of the immunoproteasome subunits low molecular protein (LMP) 2 or LMP7 was shown to reduce the presentation of certain major histocompatibility complex (MHC) class I-restricted tumour peptide epitopes in renal cell carcinoma and melanoma cells. This may provide the tumour cells with an immune escape mechanism. To test the relevance of this hypothesis, we have taken advantage of the fact that spontaneous regression of human primary melanoma is thought to be the result of a successful peptide-specific cellular immune response in vivo. Immunohistochemical staining with anti-LMP2 and anti-LMP7 xenoantibodies showed a significantly higher expression of these immunoproteasome subunits in primary melanoma lesions exhibiting histological signs of tumour regression than in primary melanoma lesions without regression phenomena. In spontaneously regressing melanoma lesions, LMP2 and LMP7 expression was significantly associated with the presence of tumour-infiltrating lymphocytes. Our results are compatible with the possibility that the expression of the immunoproteasome subunits LMP2 and LMP7 rather than their downregulation in melanoma cells is associated with the presence of a successful anti-melanoma immune response.

Spontaneous regression of primary melanoma lesions is regarded as the result of the recognition of melanoma-associated antigen (MAA)-derived peptides by cytotoxic T-lymphocytes and destruction of melanoma cells. The transporter associated with antigen processing (TAP1/2) is likely to play a crucial role in this process since it loads antigen peptides onto MHC class I molecules. To determine the impact of TAP defects on the spontaneous regression of melanoma lesions, we have compared the expression of TAP1 and TAP2 in 39 primary melanoma lesions exhibiting clinical and histological signs of tumour regression and in 35 primary melanoma lesions without regression phenomena. TAP1 expression was significantly associated with regression of melanoma lesions, since the staining pattern with anti-TAP1 antibody was positive in 38 of the 39 lesions exhibiting regression phenomena and in only 24 of the 35 lesions without histopathological signs of tumour regression. In the latter group, six lesions were stained with a heterogeneous pattern and five with a negative pattern. Furthermore, in lesions with a heterogeneous staining pattern, a clear association was found between TAP1 expression in melanoma cells and the presence of tumour-infiltrating lymphocytes. These results suggest that TAP1 plays an important role in the MAA-specific cytotoxic T-lymphocyte response, which has been suggested to underlie the spontaneous regression of primary melanoma.

Extraocular sebaceous carcinoma is a rare skin neoplasm that resembles clinically pyogenic granuloma, hemangioma or squamous cell cancer. The clinical and histological findings are described. The differential diagnosis of common tumors of the face should include this rare malignancy.

Background and Objective: The clinical differentiation of the hereditary ichthyosis forms is difficult and without laboratory markers hardly possible. Serum lipoprotein electrophoresis is one tool for detecting patients with recessive X-linked ichthyosis (XRI). Compared to controls, XRI patients show elevated electrophoretic mobilities of low density (LDL) and very low density lipoproteins (VLDL). This change in pattern is only partially explained by the increased LDL cholesterin sulfate concentration and is the subject of this study., Patients/methods: Patients suffering from XRI and ichthyosis vulgaris, healthy controls. SDS-PAGE-electrophoresis and isoelectric focusing for detection of XRI-associated variations in apolipoproteins apo B-100, apo C-III and apo E., Results: XRI-associated apolipoprotein variants were not found. In contrast to the literature, an increased electrophoretic mobility was also observed for HDL (high density lipoproteins) from XRI patients., Conclusions: The underlying cause of the increased electrophoretic mobility of VLDL and HDL in XRI patients remains unclear. Future studies should investigate other apolipoproteins and verify the cholesterin sulfate concentrations reported for VLDL and HDL from XRI patients.

Several articles have shown inferior renal allograft survival in patients receiving kidneys from young cadaver donors. We therefore assessed the survival and function of the first cadaveric graft from donors aged under 6 years of age, transplanted after 1983. The results were compared with the outcome of children receiving kidneys from older donors. Graft survival and serum creatinine were analyzed retrospectively at various time intervals after first cadaveric transplantation in 35 pediatric recipients of renal transplants grafted between 1983 and 1996 from donors < 6 years of age. Their data were compared with those of 167 pediatric recipients of renal transplants grafted from older donors. The proportion of young donors remained constant throughout the observation period. Mean recipient age was 10.4 years (range 3.2-17.5 years) in the patients grafted from donors < 6 years of age, not much different from the mean age of the donors in the 6+ years group (12.5 years, range 2.3-18.6 years). Five-year patient survival did not differ between the two groups (89 vs. 90%). In 1983-1996, graft survival rate of kidneys from donors aged < 6 years after one year was 77% (donors aged 6+ years=76%), after 2 years 66% (donors aged 6+ years=68%), after 3 years 62% (donors aged 6+ years=66%), and after 5 years 55% (donors aged 6+ years=60%, n.s., Log-rank test). In 1994-1996, 2-year graft survival was 88% (controls 91%, n.s.). In children receiving a cadaveric graft from a donor aged < 6 years, mean serum creatinine fell from 132+/-101 (SD) micromol/l after 3 months to 101+/-66 micromol/l after 12 months, and was 110+/-52 micromol/l after 5 years. This compared with a serum creatinine of 131+/-108 micromol/l after 3 months, 132+/-97 micromol/l after 12 months and 143+/-81 micromol/l after 5 years in children receiving grafts from older donors. When transplanting renal allografts from young donors into children, there was no significant difference in graft survival between donors aged < 6 years and older donors or in graft function. We conclude that good results from young donors can be obtained in a specialized center, and therefore the restriction of kidney selection to donors aged > 6 years may not be justified.

In 1243 patients after renal transplantation, 39 malignant tumours were detected in 37 patients. The average latency period between transplantation and tumour disease was 72 months. Tumours included 8 malignant lymphomas, 7 dermatomas and 24 visceral tumours. The patients who developed a tumour had received fewer blood transfusions before transplantation than a tumour-free control group of 60 patients with renal transplants. Rejection crises occurred in a significantly smaller number of tumour patients compared with the control group.

From April 1987 to November 1995, we performed 741 laparoscopic procedures, in which we observed 14 major complications (1.9% complication rate). The complication rate was 4% in the first 100 procedures--more than twice as many as in the following 631 procedures, which had a complication rate of 1.6%. Although between 1987 and 1990 laparoscopy was mainly used for the diagnosis of cryptorchidism, we then progressed to therapeutic measures with the help of the laparoscopic technique. After performing laparoscopic orchiectomy (1990), we introduced fenestration of lymphoceles (1991), varicocelectomy (1991), pelvic staging lymphadenectomy (1992), nephrectomy (1992), and adrenalectomy (1994) into clinical practice, in addition to other, more rarely occurring procedures. The complications we observed demonstrate a clear learning curve and show that critical, gradual practice of the laparoscopic technique is necessary.

Varicocele treatment was performed in 331 patients. One hundred fifteen patients were operated upon according to the technique of Bernardi (1947), 80 patients underwent occlusion of the testicular vein by detachable balloons, 47 patients were treated with percutaneous sclerotherapy, and 89 patients underwent laparoscopic varicocele treatment. The laparoscopic occlusion of the testicular vessels was done in two different ways: (1) coagulation of the testicular veins with electrocoagulating tweezers, and (2) occlusion of the suprainguinal testicular vessel with metal clips and transection of the vessels. Laparoscopic Group 1 showed a clearly higher complication rate and recurrence rate in comparison with the other methods, whereas in Group 2 we observed the best results with only 4% complications and recurrences. Because of its higher complication rate and recurrence rate, laparoscopic electrocoagulation of the testicular veins proved to be inadequate.

With the introduction of laparoscopic operating techniques in urology, this new minimally invasive method can now be used in the treatment of problematic calculi in the ureter. We report our first experience with laparoscopic laser ureterolithotomy.

Granular-cell tumors are exceedingly rare neoplasms in the central nervous system. Their histogenesis has been a subject of longstanding controversy but substantial findings support the current theory of a Schwann cell origin. Other recent histopathological studies point to an astrocytic origin in those tumors which arise from the cerebral hemispheres. A case of a granular-cell tumor arising from the trigeminal nerve is described. The origin, clinical course, radiological features, and treatment of such unusual intracerebral tumors are discussed.

Phosphorylation of phospholamban and troponin I of dog hearts was measured depending on the cardiac cycle. Myocardium biopsies were obtained with the help of an ECG-triggered cryobiopsy device. A standardized back phosphorylation technique was performed with (32P)ATP and an excess of exogenically applied c-AMP dependent protein kinase, which was followed by electrophoretic fractionation. This standardized method enables quantitative measuring especially of the c-AMP-stimulated protein phosphorylation. A dichotomous behaviour in the phosphorylation of troponin I and phospholamban was detected in the cardiac cycle. Like c-AMP and the c-AMP depended protein kinase troponin I reach a maximum phosphorylation in the systole. In contrast to this, phospholamban in vivo shows the highest degree of phosphorylation in the diastole and drops to a significant lower value (by approximately 25%) in the systole. The surprising dichotomy support the assumption that the Ca-detensivation of the contractile proteins by phosphorylation of troponin I was a dynamic counterregulation in the presence of a high Ca-level takes effect before the Ca-accumulation which can be stimulated by phospholamban. The results show that covalent modifications of regulatory proteins come to pass in the ms-range and have to be considered in distinctive conditions of myocardial function.