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Notes: We present measurements of second-harmonic generation in interband transitions of InxGa1−xN/GaN multiple quantum well samples. The second-order susceptibility χ(2) is studied as a function of pump wavelength and quantum well width. For the narrowest wells, we obtain χ(2)=1.3±0.4×10−10 m/V, which is an order of magnitude larger than the intrinsic value for bulk GaN. The corresponding power conversion efficiency was 6.3×10−7. An enhancement of the nonlinearity due to strong internal piezoelectric fields could not be observed. © 1999 American Institute of Physics.

Notes: A total of 132 patch tested patients reacted with petechial reactions to cobalt chloride 1 % in petrolatum; 23 were retested with various concentrations of cobalt. In about 60% of those retested the petechial reaction could be reproduced. Histopathological examination showed slight perivascular tymphocytic infiltration, swollen endothelium and extravasation of erythrocytes but no signs of vasculitis.It is suggested that in predisposed patients the petechial reaction following patch testing could be the result of primary irritation.

Notes: The availability of molecular markers linked to mildew resistance genes would enhance the efficiency of apple-breeding programmes. This investigation focuses on the identification of random amplified polymorphic DNA (RAPD) markers linked to the Pl1 gene for mildew resistance, which has introgressed from Malus robusta into cultivated apples. The RAPD marker technique was combined with a modified ‘bulked seg-regant analysis’ mapping strategy. About 850 random decamer primers used as single primers or in combinations were tested by PCR analysis on the basis of resistant and susceptible DNA pools. Selected primers producing RAPD fragments were applied in an additional selection step to M. robusta and genotypes representing intermediate breeding stages of the breeding population 93/9, for which a 1:1 segregation could be observed for the resistance trait. Seven RAPD markers, all representing introgressed DNA sequences from M. robusta, were identified and arranged with the Pl1 locus in a common linkage group. The two most tightly-linked RAPD markers, OPAT20450 and OPD21000 were mapped with a genetic distance of 4.5 and 5 cM, respectively, from the Pl1 gene. Both markers are suitable for marker-assisted selection in apple breeding. The polymorphic DNA fragment OPAT20450 was cloned and sequenced, and longer primers for the generation of a sequence-characterized amplified region (SCAR) marker have been constructed; this marker was easier to score than the original RAPD marker.

Notes: Formation of the lignocaine metabolite monoethyl-glycine-xylidide (MEGX) by hepatic cytochrome P450 enzymes is a new method for evaluating liver function. The purpose of this study was to compare MEGX formation with other liver function parameters in surgical intensive care unit patients. The study included 29 critically ill patients who had been admitted to the unit for more than 3 days with a median APACHE III score-predicted mortality 〉 30%. On day 4, lignocaine was given intravenously at a dose of 1 mg.kg-1 over 2 min and MEGX formation was measured 15 min later. Eighty-nine percent of the patients had MEGX values below 90μg.l-1 indicating impaired liver function. Eleven patients died, 18 patients survived. The group of patients with fatal outcome had significantly lower MEGX values (median: 23μg.l-1) than the group of survivors (median: 53μg.l-1, p 〈 0.01). Bilirubin values were elevated in the non-survivor group (median: 2.8mg.dl-1) compared to the survivors (median: 0.9mg.dl-1, p 〈 0.05). There was no significant difference between the two groups in the other liver function tests. We conclude from our results that the MEGX test can be considered an indicator for hepatic dysfunction and predictor of survival in critically ill patients.

Notes: Summary. Radiological and orthopaedic outcome in severe and moderate haemophilia A and B patients undergoing long-term prophylactic treatment were prospectively investigated focusing on the age of onset of prophylaxis and the number of joint bleedings prior to treatment. We report on 21 patients with severe and moderate haemophilia A and B receiving prophylactic treatment of between 3.1 and 16.1 year's duration. Three patient groups were evaluated according to the age at onset of prophylaxis. In group I prophylactic treatment was initiated in the first 2 years of life. Patients in group II received prophylaxis at the age of 3–6 years. Late-onset or secondary prophylactic treatment was started at the age of 6 years and above in seven patients (group III). All patients received virus-inactivated F VIII or F IX concentrates at dosages of 30–50 IU/kg body weight i.v. three times per week for those with haemophilia A and twice per week for those with haemophilia B. Elbow, knee and ankle joints were investigated at 3–4-yearly intervals according to the radiological and orthopaedic scores recommended by the World Federation of Haemophilia. The total number of joint bleedings before and after start of prophylaxis were recorded in all patients. In group I 7/8 patients had unaffected joints with constant radiological and orthopaedic scores of zero or 1, after a median of 11.25 years of prophylactic treatment. One patient in this group demonstrated mild radiological alterations (score 4). Patients in group II showed neither radiological nor orthopaedic alterations at study entry. Surprisingly, worsening joint scores could be detected despite ongoing prophylaxis after the 3-year interval (median orthopaedic score 4, median radiological score 8). Treatment group III already showed considerable joint damage at study entry with a median radiological score of 11 (0–33) and a median orthopaedic score of 4 (0–11). Despite prophylactic treatment, both radiological (median 19.5, range 2–47) and orthopaedic scores (median 8, range 2–12) deteriorated after 3 years. Prior to onset of prophylaxis, no or only one joint bleeding occurred in treatment group I. In group II, a median of six joint bleeds (range 1–8) was reported before prophylaxis was started. Patients in group III usually experienced a median of more than 10 joint haemorrhages (range 6–10 or more). Under prophylactic treatment the number of joint bleedings decreased significantly in group II and III. However, radiological and orthopaedic scores increased as a sign of progressing osteoarthropathic alterations in patients reporting more than five joint haemorrhages before onset of prophylaxis whereas no joint alterations could be assessed in patients with no or only one joint bleeding episode prior to prophylaxis. Even a small number of joint bleedings seems to cause irreversible osteoarthropathic alterations leading to haemophilic arthropathy. Once apparent, further progression of joint damage could not be arrested despite of prophylactic treatment (groups II and III). In order to prevent haemophilic arthropathy, effective prophylaxis should be started before or at least after the first joint bleeding in severe haemophilia A and B.

Notes: Brown trout Salmo trutta populations of numerous Swiss rivers are declining. Sewage plant effluents are discussed as a possible cause. To investigate the influence of sewage plant effluents, brown trout as well as rainbow trout Oncorhynchus mykiss were exposed to 10% diluted waste water over a period of 12 months. The effects were compared to those on trout kept in commercial tap water. The mortality rate was low and no pathogenic bacteria or viruses were recorded in exposed and tap-water animals. Parasitological examination revealed a mild infestation with Gryodactylus sp. in all groups. Macroscopically and histologically, only minor changes in gills, skin, and kidney of exposed animals were found when compared to fish kept in tap water. Degenerative and inflammatory reactions in the liver of exposed animals were the most prominent findings. Several brown trout caught in the River Langete showed marked proliferative, degenerative and inflammatory lesions of gills, liver, and kidney. The results do not suggest that waste-water effects would explain the decrease of fish populations. However, it is conceivable that the effluents in combination with other factors in the river enhance the development of changes.

Notes: Water pollution induces pathological changes in fish. As an indicator of exposure to contaminants, histology represents a useful tool to assess the degree of pollution, particularly for sub-lethal and chronic effects. However, a standardized method for the description and assessment of histological changes, mainly for use in freshwater fish, is still lacking. In this paper, the present authors propose a standardized tool for the assessment of histological findings which can be applied to different organs. The methodology is based on two factors: (1) the extension of a pathological change is rated with a ‘score value’; and (2) the pathological importance of this alteration is defined as an ‘importance factor’. The sum of the multiplied score values and importance factors of all diagnosed changes results in different indices. With these indices, statistical analysis can be carried out. Assessment methods for the gills, liver, kidney and skin are described.