Micro-determination of bromine in biological samples using proton-induced x-ray emission spectroscopy

The plasma level of bromine was measured by a proton-induced X-ray emission spectroscopy. Since bromine is the most difficult halogen to be determined and appears only in trace quantities, powerful techniques are required. The excellent reproducibility was obtained on 19 measurements on a sample of a single individual; the coefficient of variation was 6.3%. The average and standard deviation of plasma bromine levels on 47 young women were 0.50 and 0.10 mg/100 ml, respectively. Results by other methods in the literature were briefly reviewed.

Inhibitory effect of L-glutamine on gastric irritation and back diffusion of gastric acid in response to aspirin in the rat

L-Glutamine given orally at 750 mg/kg significantly reduced the formation of gastric mucosal lesions induced by aspirin at 100 mg/kg at 1, 3, and 7 hours in pylorus-ligated rats. L-Glutamine markedly inhibited the loss of H+ and a corresponding increment of Na+ through the aspirin-damaged mucosal barrier, which suggests inhibition of acid back diffusion as the mechanism of action. In vagotomized rats, the diffusion of H+ from the instilled acid solution into the gastric mucosa and outflux of Na+ from the mucosa into the lumen was so strong that aspirin could not show any acceleration of a back diffusion of H+ in contrast to the aspirin-free group. However, L-Glutamine given with or without aspirin inhibited the group. However, L-Glutamine given with or without aspirin inhibited the back diffusion of H+ instilled into the vagotomized rat stomach.

Complexes between synthetic polymer ligands and ferri-delta and ferro-protoporphyrin IX

The complexes of synthetic polymer ligands, i.e. poly-L-lysine, poly-4-vinyl-pyridine, poly-N-vinyl-2-methylimidazole and the higher branched polyethyleneimine, with ferri- or ferro-protoporphyrin IX were studied from the standpoint of polymer ligand effects by comparison with those of their monomeric model ligand complexes and poly-gamma-benzyl-L-glutamate containing an imidazole nucleus at the chain end. The coordination numbers and formation constants were determined optically and their structures were also estimated. The coordination number of a poly-L-lysine complex was two, but those of other polymer ligand complexes were one. One of the polymer effects, which was indicated by the large formation constants of the polymer complexes, was caused by the increment of the local ligand concentration around the polymer chain. Another was caused by the conformational effect of an alpha-helical structure in the poly-L-lysine complexes. The interaction of a poly-L-lysine-heme complex with molecular oxygen was also studied. An observed pseudo-allosteric phenomenon may be due to the specific structure of a poly-L-lysine complex which is different from those of other polymer ligand complexes.

Fishery Joint Ventures in Developing Countries

To an increasing degree joint ventures are being used to assist developing nations to make better use of the fishery resources in their own waters or adjacent thereof. Japan has been active in this field, providing technical assistance, equipment, training, and fellowships. The Japanese fishing industry has also provided capital and skills.The first Japanese fisheries joint venture was established in 1953 and the system has grown rapidly since; by March 1972 there were 38 countries involved, with 77 enterprises and a capital investment of $25 million. Most joint ventures have been established in Asia and Oceania; Africa has shown the greatest increase in recent years. Most enterprises are for fishing activities, especially trawl fishing for shrimp; the others are for cold storage, fish processing, and aquaculture.About 46% of joint venture enterprises are owned mostly by Japan, but increasingly the local country has an equal or larger share. Most land-based employees are of the local country, but over half the fishermen are Japanese; this reflects the difficulty of obtaining enough skilled local fishermen. One task of the ventures should be to train such men.Successful joint ventures require the following: The national interest of the recipient country should be kept fully in mind; Recipient countries should take the steps necessary for resource conservation, for prevention of conflicts on the fishing grounds, and for avoiding excessive competition; Fisheries require complex infrastructures, including harbors and supply and storage facilities, which cannot be supplied by commercial enterprises. Arrangements should be made by the recipient country to provide these, by the government or through bilateral or multilateral assistance; and Recipient governments should fully appreciate the characteristics and risks of fishery ventures, and take a long view of development. They should recognize the need for exploratory and experimental fishing, and give favorable treatment regarding taxation, employment, import of fishing materials, and remittance of foreign exchange.