Mutation analyses of KRAS exon 1 comparing three different techniques: temporal temperature gradient electrophoresis, constant denaturant capillary electrophoresis and allele specific polymerase chain reaction

Pefloxacin plus metronidazole versus netilmicin plus metronidazole in the prevention of nosocomial infections during contaminated surgery. Surgical prophylaxis is widely used in contaminated surgery, especially colorectal surgery. In this clinical trial the efficacy of pefloxacin 800 mg i.v. slow infusion associated to metronidazole 500 mg i.v. 1-2 hours before surgery and then metronidazole alone after 6 and 12 hours versus netilmicin 200 mg i.m. associated to metronidazole 500 mg i.v. 1-2 hours before surgery and then both after 6 and 12 hours were evaluated in 97 patients suffering by colorectal surgery. Efficacy of prophylaxis in patients was evaluated in terms of appearance of post-surgical infections (abdominal, urinary, respiratory and wound infections). In pefloxacin + metronidazole group (53 patients), two cases of wound infections (3.8%) and three cases of respiratory infections (5.8%) were observed. In netilmicin + metronidazole group (44 patients), two cases of wound infections (4.9%), three cases of urinary infections (7%), three cases of respiratory infections (7.5%) and one case of intra-abdominal infection were observed. Our data confirmed that in colorectal surgery, the association pefloxacin, drug with microbiological and pharmacokinetics characteristics suitable for prophylaxis + metronidazole, active against anaerobes pathogens, prevents post-surgical infections as well as a reference association (netilmicin + metronidazole), with the advantage of a single administration.     

Myoblast city, the Drosophila homolog of DOCK180/CED-5, is required in a Rac signaling pathway utilized for multiple developmental processes

The Rac and Cdc42 GTPases share several regulators and effectors, yet perform distinct biological functions. The factors determining such specificity in vivo have not been identified. In a mutational screen in Drosophila to identify Rac-specific signaling components, we isolated 11 alleles of myoblast city (mbc). mbc mutant embryos exhibit defects in dorsal closure, myogenesis, and neural development. DOCK180, the mammalian homolog of Mbc, associates with Rac, but not Cdc42, in a nucleotide-independent manner. These results suggest that Mbc is a specific upstream regulator of Rac activity that mediates several morphogenetic processes in Drosophila embryogenesis.     

The HIV-epidemic among drug addicts in Norway

Up to 1996, 368 persons in Norway (population 4.3 million) had been reported as being HIV-infected because of intravenous drug use. 72 of these had developed AIDS and 59 had died from AIDS. HIV-testing is very common among drug users in Norway and new cases are rarely detected at treatment centres or at autopsy. Some 15-30 cases may still be undiagnosed. HIV spread very rapidly among drug users in Norway in 1984 and 1985, by around 100 new cases per year. Since then, the annual incidence has decreased from 30-40 cases in 1986 to 10-15 in 1995. Although the drug users seldom shared syringes even before the advent of the HIV epidemic, we believe that the public rehabilitation programmes, needle exchange programmes and health information have contributed to control HIV in this group. We expect an annual incidence of 10-15 cases the next five years.     

The HIV-epidemic in Norway 1996--mainly heterosexual transmission

Up to 1996, a total of 1,537 individuals had been reported as having HIV infection in Norway (population 4.3 million). 511 of these had developed AIDS and 410 had died from AIDS. 223 persons had acquired HIV heterosexually. Less than a fifth of these had acquired the infection from persons who themselves had been infected with HIV heterosexually in Norway. Named testing of pregnant women, recruits and blood donors confirms the limited spread of HIV. We estimate that the annual incidence of heterosexually acquired HIV infection has remained at 20-30 for the last ten years. Earlier prognoses for the epidemic in Norway were grossly erroneous, mainly owing to lack of knowledge about the factors determining the spread of HIV. Given the low rate of transmission of the virus and the sexual behaviour of Norwegians, there was never any real danger of a large heterosexual HIV epidemic in this country. The future efforts to combat the epidemic should focus on maintaining features that make Norwegian society less vulnerable to HIV.     

Clinical and pathologic characteristics of bladder squamous carcinoma

From 1973 to 1991, 782 patients with bladder tumor were admitted to this hospital. 23 (2.9%) of them were pathologically confirmed as squamous carcinoma. Clinically, 20 patients showed hematuria, 3 irritation signs of bladder, and 13 both signs. In this group, 82% the tumors belonged to B to D stage and 61% were of grade II. Six of 17 patients showed diffused eosinophil cell infiltration, suggesting a close relationship between bladder squamous carcinoma and inflammation. Bladder polycentric biopsy and exfoliative cytologic urocrisia were emphasized in preoperative diagnosis.     

Effect of topical aclacinomycin on glaucoma filtration surgery in rabbits

A prospective, randomized, double-masked and placebo-controlled study was performed to compare the effects of a single 5-minute intraoperative exposure to aclacinomycin (AMC) 0.4 mg/ml or 0.8 mg/ml with control eyes treated with saline solution on the success of glaucoma filtration surgery in 26 rabbits. Intraocular pressure (IOP), bleb survival, fistula patency and complications were evaluated. The results showed that IOP in the eyes treated with AMC was significantly lower than that in the control eyes from days 5-40 in the 0.4 mg/ml group and from days 5-20 in the 0.8 mg/ml group. The bleb survival lasted significantly longer in the two treated groups than in the control group and in the AMC 0.4 mg/ml group than in the AMC 0.8 mg/ml group. At 40 days, the rate of sclera fistula occlusion was 0% in the AMC 0.4 mg/ml eyes, 43.8% in the AMC 0.8 mg/ml eyes, and 100% in the control eyes. Significant complications, such as anterior chamber inflammation, hyphema, moderate and severe corneal haze, dense corneal neovascularization and mild cataract occurred only in the eyes treated with AMC 0.8 mg/ml. The results indicated that intraocular treatment with AMC at a dose of 0.4 mg/ml had a markedly beneficial effect on IOP, bleb appearance and fistula patency after experimental filtration surgery in rabbits.     

Communicable disease control in connection with international air traffic to Norway

International air traffic has increased the risk of importation of infectious diseases to Norway. We have used notification data and a theoretical framework to assess the risk of importation and subsequent disemination of serious infectious diseases in Norway. Every year, a few cases of these diseases are imported to Norway, especially malaria, shigellosis and typhoid fever. A few secondary cases of enteric diseases may occur, but epidemics are unlikely. Counselling and immunisation of Norwegians going abroad is the first step in prevention. Secondly, health services all over the country should be able to diagnose imported diseases early and institute infection control measures. However, there is no need for concentrating resources for disease control at international airports in Norway.     

Arginine-481 mutation abolishes ligand-binding of the AMPA-selective glutamate receptor channel alpha1-subunit

Arginine-481 is located in the putative agonist-binding region preceding the putative transmembrane segment M1 of the alpha1-subunit of the AMPA-selective glutamate receptor (GluR) channel. This amino acid is completely conserved among GluR proteins. A site-directed mutagenesis study using a baculovirus expression system showed that substitution of glutamate, glutamine and lysine for arginine-481 of the recombinant alpha1-subunit protein abolishes binding to [3H]AMPA completely. The present study provides the first direct experimental evidence that the conserved charged arginine-481 residue is essential, directly or indirectly, for the acquisition of ligand-binding activity by the receptor protein.     

Structure-activity relationship studies of chalcones as SRS-A receptor antagonists

A simple, reliable and highly sensitive bioassay with sensitized longitudinal strips of guinea pig ileum was used for screening the receptor antagonists of slow reacting substance of anaphylaxis (SRS-A). The SRS-A receptor antagonistic activities of 17 chalcones were studied. Most compounds in these chalcones were found to have SRS-A receptor antagonistic action at the concentration of 10(-4) mol.L-1. Among them, compounds 5, 13 and 17 were highly effective with IC50s of 7.5 x 10(-6), 7.5 x 10(-6) and 6.8 x 10(-5) mol.L-1, respectively. Under the same conditions, the IC50 of FPL 55712, a known leukotriene D4 receptor antagonist, was shown to be 3 x 10(-4) mol.L-1. It would appear that compounds 5, 13 and 17 were 40, 40 and 4.4 times more potent, respectively, than FPL 55712. From analysis of structure-activity relationship of chalcones, these results suggest that the following factors may be important for an active antagonist of SRS-A receptors: (a) There is a system of pi, pi conjugation in the molecule; (b) The ester group in the B ring of chalcones is more favorable than the carboxyl group; (c) Antagonism for meta- or para-substituted derivatives of carboxyl or ester group in the B ring are more potent than ortho-substituted compounds; (d) The length of carbon chain of alkyl group in the A ring of chalcones is more effective for 1, 4 or 6 carbon atoms than for 10 or 14 carbon atoms.