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A detailed analysis of fishing records has shown that the shark species accessible to global fisheries have been systematically depleted for decades. They were already fished to about 10 percent of their former levels by 2003. Now one species after another is being listed on the IUCN Red List of Threatened Species as their numbers drop towards extinction. Shark depletion has not been well documented and a large proportion of shark mortality has been bycatch, the target species being teleost fish. But with the rise in value of shark fins due to the shark fin trade, at the same time as teleost fish stocks have become severely overfished, sharks, along with tuna, have become the most valuable catches. Fishing on the high seas is scarcely profitable, and so is heavily supported by subsidies. But the shark fin trade, in which organized crime is heavily involved, is driven by enormous profits and provides a powerful demand for the fins of all sharks. Thus it is now being supplied by fisheries around the world. There is no interest in sustainability in consumer countries, and neither the will nor the resources to manage the trade exist. Although some shark fisheries might have been managed sustainably in some regions for certain species for meat, such fisheries are increasingly dependent on the shark fin trade.. The rising global demand for shark fins, coupled with the increasing depletion of the animals supplying that demand, makes commercial fishing for sharks unsustainable. Given their high ecological value across the aquatic ecosystems they inhabit, it is important that they receive more effective measures of protection going far beyond the currently existing ones. In particular, protection of all sharks, manta rays, devil rays and rhino rays through an Appendix I CITES listing should be effected immediately due to the scale of the global take of the shark fin trade and the state of shark depletion amply documented in the literature.

Hintergrund: Als frühe Diabetesauswirkung am Auge können subklinische Veränderungen wie verminderte Kontrastempfindlichkeit und elektrophysiologische Abweichungen als Zeichen einer retinalen Neurodegeneration auftreten. Die optische Kohärenztomographie (OCT) bietet die Möglichkeit,[for full text, please go to the a.m. URL], 27. Jahrestagung der Retinologischen Gesellschaft

Hintergrund: Auswertungen von Datenbanken für unerwünschte Arzneimittelwirkungen (UAW) und pharmakoepidemiologische Studien zeigen, dass UAW bei Frauen häufiger als bei Männern gemeldet werden. Dies gilt auch für Anästhetika. Eine systematische Übersicht der wissenschaftlichen[for full text, please go to the a.m. URL], EbM & Individualisierte Medizin; 12. Jahrestagung des Deutschen Netzwerks Evidenzbasierte Medizin

A glycoprotein was selectively enriched in the supernatant (Fraction b) obtained by alcohol and trichloroacetic acid fractionation of digitonin extracts from blood of patients with neoplastic diseases and of control subjects. Subsequent chromatography with concanavalin A:Sepharose separated a concanavalin A-reactive fraction from a concanavalin A-nonreactive one. In sodium dodecyl sulfate gel electrophoresis, the fractions from both malignant origin as well as control subjects appeared as single bands showing the same mobility. They were identical with the band obtained from commercial α1-acid glycoprotein. In Fraction b of malignant origin, greatly increased amounts of the α1-acid glycoprotein from malignant cases (AGP(M)) were found as compared to α1-acid glycoprotein from controls (AGP(C)). Furthermore, AGP(C) had a higher glycine content than did AGP(M). The electrofocusing pattern of AGP(M) showed additional bands between pH 3.7 and 4.4, whereas AGP(C) and commercial α1-acid glycoprotein focused between pH 3.2 and 3.8. In contrast to AGP(C) and to a commercial α1-acid glycoprotein, AGP(M) is characterized by a chromophoric group with maximal absorbance at 400 nm. It could be detached by treatment with 6 M guanidine hydrochloride, thus indicating a noncovalent binding. The spectral data of the separated chromophore at pH 0.5 agreed with that of a 6,7-substituted pteridine. After detachment with reducing agents, a pteridine in its 7k8-dihydro form was indicated by spectral analysis.

Biopterin accumulation had been demonstrated as the result of normal and, especially, of malignant hemopoietic cell proliferation (Ziegler, I. et al. Blut, 44: 231-240, and 261-270, 1982). Among 13 major intermediates of pterin metabolism and two lumazines, xanthopterin (but not dihydroxanthopterin) was found to inhibit cell proliferation (half-maximum inhibition at 1.8 X 10(-5) M) during concanavalin A-induced lymphocyte activation in pre-stimulated lymphocytes and in a lymphoid cell line grown in continuous culture (LS-2). LS-2 cells exposed to maximum inhibitor concentrations largely maintained the initial thymidine incorporation rate for about 40 hr but failed to enter logarithmic growth. Isoxanthopterin inhibition was found only in serum-free medium, since it is trapped by the alpha-acid glycoprotein present in the serum. The reduced biopterin derivatives, sepiapterin, dihydrobiopterin, and tetrahydrobiopterin, are costimulators during concanavalin A-induced lymphocyte activation. Their costimulatory effect follows an optimum curve and peaks at 1.5 to 3 X 10(-5) M. It is highest at the suboptimal and supraoptimal concanavalin A concentration. The D-erythro isomer dihydroneopterin was inactive. The results indicate that the anabolic-reduced biopterin derivatives are not simply lymphocytic products, but, in combination with the catabolites xanthopterin and isoxanthopterin, they also participate in the regulation of lymphocyte activation. Hence, they fulfill the criteria for lymphokines.

In Triturus cristatus amputation causes the reappearance of larval tetrahydrobiopterin, thusraising the ratios tetrahydrobiopterin/isoxanthopterin and tetrahydrobiopterin/riboflavin from zeroto values between 3 — 5. This increase first occurs in the remaining skin and in the eyes. Theincrease of both ratios in the regeneration bud, beginning with the 20th day after amputation, coincides with their drop in both other tissues. Chloramphenicol and isoxanthopterin both stronglyinhibit the formation of a regeneration bud. They also block the increase of both ratios in theremaining skin and in the rudimental regenerate as well. Reserpine induces regenerative ability in Triturus vulgaris, which normally lacks this. It has a strong melanizing effect and, moreover, itcauses an increase of both ratios in the regeneration bud and in the remaining skin. © 1972, Walter de Gruyter. All rights reserved.

Human squamous cell carcinoma has elevated levels of tetrahydrobiopterin. As the level of riboflavin is low, the ratio tetrahydrobiopterin/riboflavin shows values of 5 — 8.3. In contrast, indifferentiated tissues with high metabolic activity but low mitotic rate, like submaxillary glands, elevated levels of tetrahydrobiopterin are accompanied by high content of riboflavin. Thus theratio tetrahydrobiopterin/riboflavin in kept as low as about 0.5. Chloramphenicol and, in particular, isoxanthopterin reduce tumor growth in rats and prevent tetrahydrobiopterin accumulation as well. © 1972, Walter de Gruyter. All rights reserved.