Growth rate of malignant tumors of the large intestine

The rates of colonic tumor growth were studied on the basis of evaluation of the case histories of 19 cancer patients in whom dynamic endocolonoscopy had been carried out. In some cases, malignant tumors appeared in the colon within 12 months after previous colonoscopy. Tumors were under 2.0 cm in size and were not accompanied by any clinical symptoms. Repeated endoscopic examinations performed within a period of 1-3 years detected large tumors which caused the constriction of colonic lumen. Clinical symptoms developed in such patients approximately 1-4 months prior to tumor detection. It is concluded that although the rates of growth of colonic malignancies are rather high, tumorigenesis is preceded by a long-term stage of preclinical disease.     

The effects of anemia on heme synthesis parameters during lead exposure

The effects of anemia during lead exposures were studied using an infant baboon animal model. When the hemoglobin concentration was reduced to less than 70% of normal, a marked blood lead increase was observed and the free erythrocyte porphyrin value, aminolevulinic acid dehydratase activity and reticulocyte counts increased. Special emphasis should be placed on nutritional effects in lead exposures.     

Effect of hypoxemia on the erythropoietic activity of organs during perfusion

Hypoxemia (45-minute) influence in vivo on erythropoietic activity of the kidney, liver, spleen, and sternum was studied by normoxemic perfusion of the isolated organs. The erythropoietic activity proved to increase after 6-hour perfusion of the liver; this confirmed the participation of this organ in the extrarenal secretion of the erythropoietic factor.     

The muscarinic acetylcholine antagonist scopolamine impairs short-distance homing pigeon navigation

The present study employed intramuscular (i.m.) injections of the acetylcholine (ACh) receptor antagonist scopolamine hydrobromide (0.10 mg/kg) to investigate the possible involvement of ACh in naturally occurring spatial navigation in homing pigeons (Columba livia). Control pigeons receiving injections of saline or scopolamine methylbromide, an ACh antagonist that does not cross the blood-brain barrier, were oriented in a homeward direction when released from a location 8 km from home. In contrast, pigeons injected with scopolamine hydrobromide (0.10 mg/kg, i.m.) were less well oriented and took more time to return home from the same location. These results suggest that homing pigeon navigation is regulated, in part, by central cholinergic mechanisms.     

131I dose-dependent thyroid autoimmune disorders in children living around Chernobyl

The nucleotide sequence of 35,400 bp at approximately 10 kb from the right telomere of chromosome VII was determined. The segment contains the MAL1 locus, one of the five unlinked loci sufficient for maltose utilization. Until now, each of these loci was considered to contain three genes (for regulator, permease and alpha-glucosidase), but a fourth gene, presumably an extra alpha-glucosidase gene, was found at MAL1 adjacent to the usual cluster of three genes. The two glucosidase genes are present in opposite orientation, forming an inverted repeat structure. In addition to the four genes at MAL1, there are 11 complete, non-overlapping open reading frames (ORFs) longer than 300 bp in the sequence presented here. A new ABC transporter gene (YGR281w), required for oligomycin resistance was found (YOR1; Katzman et al., 1995), and the previously sequenced BGL2 (YGR282c), ZUO1 (YGR285c) and BIO2 (YGR286c) genes were located. The sequence of BIO2, a biotin synthetase gene, required substantial correction and the size of Bio2p is 375, rather than 356, amino acids. Two ORFs show rather weak similarities to animal genes: YGR278w to an unknown ORF of Caenorhabditis elegans and YGR284c to the murine Surf-4, a member of a cluster of at least four housekeeping genes. The remaining five ORFs do not encode known functions, but three of these show weak to high similarities to other ORFs in the Saccharomyces cerevisiae genome and one (YGR280c) codes for a particularly lysine-rich protein.     

The significance of gastric helicobacteriosis in the genesis hemorrhage from duodenal peptic ulcer

Based on a comprehensive analysis of findings from examination and surgical treatment of 196 patients with bleeding pyloroduodenal ulcers, it was found out that patients with concurrent helicobacteriosis of the stomach are prone to more unfavourable course of their illness, which fact is evidenced by a greater loss of blood and higher risk for bleeding recurrences. A classification is proposed by the authors, taking advantage of the data from endoscopic, microscopic and immunoenzymatic techniques, with the purpose of providing an assessment of degree of severity of helicobacteriosis of the stomach.