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An international round-robin experiment has been conducted to test procedures and methods for the measurement of angle-resolved light scattering. ASTM E2387-05 has been used as the main guide, while the experience gained should also contribute to the new ISO standard of angle-resolved scattering currently under development (ISO/WD 19986:2016). Seven laboratories from Europe and the United States measured the angle-resolved scattering from Al/SiO2-coated substrates, transparent substrates, volume diffusors, quasi-volume diffusors, white calibration standards, and grating samples at laser wavelengths in the UV, VIS, and NIR spectra. Results were sent to Fraunhofer IOF, which coordinated the experiments and analyzed the data, while ESA-ESTEC, as the project donor, defined conditions and parameters. Depending mainly on the sample type, overall good to reasonable agreements were observed, with largest deviations at scattering angles very close to the specular beam. Volume diffusor characterization unexpectedly turned out to be challenging. Not all participants provided measurement uncertainty ranges according to the Guide to the Expression of Uncertainty in Measurement; often, a single general scatterometer-related measurement uncertainty value was stated. Although relative instrument measurement uncertainties close to 1% are sometimes claimed, the comparison results did not support these claims for specular scattering samples as mirrors, substrates, or gratings.

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Increased serum homocysteine (Hcy) can induce liver diseases and can play a remarkable role in hepatic disorders. The purpose of the present study therefore was to investigate the relationship between serum vitamin B(12), folate, zinc and copper, cysteine, and Hcy level differences between cirrhotic patients and healthy subjects. We studied 32 cirrhotic patients (12 females and 20 males) aged 45 +/- 11 years and 32 control subjects (12 females and 20 males) aged 39 +/- 9 years. There was an inverse correlation between Hcy and vitamin B(12) in controls (r = -0.442, p < 0.011) but not in cirrhotic patients (r = -0.147, not significant). Also, mean plasma folate was decreased in cirrhotic patients compared to controls (p < 0.001). Copper increased whereas zinc decreased significantly in cirrhotic patients. A positive correlation was seen between the Cu/Zn ratio and Cu in controls (r = 0.690, p < 0.01), but the correlation between the Cu/Zn ratio and Cu was not significant in the cirrhotic group. Negative correlations were seen between plasma concentration of zinc and the Cu/Zn ratio in controls and cirrhotic patients (r = -0.618, p < 0.01 and r = -0.670, p < 0.01, respectively). Cirrhotic patients displayed multiple abnormalities, including changes in cysteine metabolism and in zinc and copper levels. Although hyperhomocysteinemia is known as an atherogenic and thrombogenic risk factor for cardiovascular disease, it might also be a risk factor for cirrhotic patients. Plasma Hcy, vitamin B(12), and folic acid measurement may be useful in the evaluation of cirrhotic patients.

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In 38C B lymphocytes the membrane form of IgM is displayed on the cell surface whereas the secretory form of IgM is degraded. In the EH cell line, a light chain-deficient variant of 38C cells, the mu heavy chains are partially assembled with surrogate light chains characteristic of pre-B cells. In these cells neither the membrane (microns) nor the secretory (microsecond) forms of the mu heavy chain reach their final destination, and both are rapidly degraded. The degradation of mu chains in EH cells, like that of microsecond in 38C cells, is nonlysosomal and occurs prior to the trans-Golgi. However, while microsecond degradation in 38C cells is inhibited by brefeldin A, in EH cells microsecond and micron are retained and degraded by a brefeldin A-insensitive mechanism. These results indicate that degradation in EH cells occurs within the endoplasmic reticulum, whereas degradation in 38C cells requires exit from this compartment. Thus, mu heavy chains can be degraded in multiple sites along the secretory pathway. The location of the degradation process is determined by the developmentally regulated assembly species of the mu chains with either "classical" or surrogate light chains.

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In this study, we investigated the ocular and visual side effects of systemic cyclosporine used as an immunosuppressant in 51 renal transplant recipients during the postoperative period. Three different treatment schemes were used. The patients in the first group received cyclosporine and a corticosteroid. The second group was given azathioprine and a corticosteroid. Those in the third group were treated with azathioprine, a corticosteroid, and cyclosporine. Cotton-wool exudates, retinal hemorrhages, and retinal artery branch occlusion were observed only in one patient each in the second group, and these patients were excluded from the statistical evaluation. Macular hyperpigmentation was observed as a new finding in each group, but there was no statistical difference between the groups. The same results were found for cataract; this probably was related to the use of steroids. Trichomegaly, visual hallucinations, and cerebral blindness were not observed by contrast with previous studies. We suggest that systemic cyclosporine does not have significant ocular and visual side effects.

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