HLA class I gene expression on human primary tumours and autologous metastases: demonstration of selective losses of HLA antigens on colorectal, gastric and laryngeal carcinomas

The expression of HLA class I antigens was studied in 99 primary tumour (colorectal, gastric and laryngeal carcinomas) and 57 autologous metastases using immunohistological techniques and monoclonal antibodies against class I monomorphic determinants, HLA-B isotypic determinants and HLA polymorphic determinants. Fourteen per cent of colorectal, 9.6% of gastric and 20% of laryngeal carcinomas completely lacked class I molecules. Selective losses of HLA-B antigens were also detected in 8.8, 3.4 and 5.8% of these tumours respectively. Taking into account complete and selective loss of HLA-B the average alteration in the class I molecules expression totalled 21%. The comparison of class I expression between primary tumours and autologous metastases showed differences in 24% of the patients. These differences consisted mainly in a decrease of class I expression by metastases. Nevertheless, four types of divergence were detected in laryngeal carcinomas, namely: +/-, +/+, -/+, -/-. In addition, a clear correlation between degree of differentiation and class I expression was observed in laryngeal tumours. Finally, when class I gene RFLPs were compared with DNA from 15 tumours and autologous normal mucosa or peripheral lymphocytes, no differences were detected between these samples.

[Pathogenic agents in acute non-enterocolic diarrheal syndrome]

Along a one year period 112 infants admitted with non enterocolic acute diarrhea were studied for isolation of potentially ethiologic agents, namely enteropathogenic bacteria (Salmonella, Shigella, Campylobacter, classic enteropathogenic, enteroinvasive and enterotoxigenic Escherichia coli), Rotavirus (viral RNA electrophoresis) and enteroparasites (Telemann and PAFS). The most frequently identified pathogen was rotavirus (57.8%), followed by thermo labile toxin producing Escherichia coli (19.7%). The frequency of classic enteropathogenic Escherichia coli was 13.9%, that of thermo stable toxin producing Escherichia coli 5.7%, Shigella 4.1%, Campylobacter 3.3% and Salmonella 1.6%. Bacteriae were isolated from 40.2%, of patients, predominantly in summer. Enteroparasites were detected in 13.1% of the cases, Entamoeba histolytica being the most frequent. In 32.8% of the cases more than one pathogen was isolated.

Protein-primed replication of bacteriophage phi 29 DNA

The replication of phi 29 DNA-protein p3 represents a simple model system to study the protein-priming mechanism of initiation of replication. The phi 29 DNA polymerase involved both in the initiation and elongation steps of phi 29 DNA-protein p3 replication, is a very processive enzyme and it is able to produce strand-displacement in the absence of other proteins. To correlate functional and structural domains in the phi 29 DNA polymerase point mutants in the most carboxyl region of amino-acid homology with other DNA polymerases have been constructed. Most of the mutations had a decreased initiation and elongation activity, but normal 3'----5' exonuclease activity, suggesting that this region contributes to the active domain for initiation and elongation. Point and deletion mutants in the terminal protein have allowed the mapping of one DNA-binding region and two DNA-polymerase-binding regions. The viral protein p6, which stimulates the initiation of replication, binds to a set of specific signals present at both phi 29 DNA ends. A good correlation of binding and stimulation of replication has been obtained by using fragments containing phi 29 DNA-terminal sequences and deletion mutants of protein p6. The viral protein p5 has been shown to bind to single-stranded DNA, to protect the latter against nuclease digetion, and to stimulate phi 29 DNA-protein p3 replication in vitro.

Empyema caused by Kingella denitrificans and Peptostreptococcus spp. in a patient with bronchogenic carcinoma

Empyema caused by Kingella denitrificans and Peptostreptococcus spp. was diagnosed in a patient with bronchogenic carcinoma. This appears to be the third report providing evidence of a pathogenic role for K. denitrificans, and the first concerning infection in the pleural space and in a patient with underlying immunosuppressive disease. K. denitrificans should be added to the list of fastidious gram-negative bacteria associated with opportunistic infections in the compromised host.

Characterization of the origins of replication of bacteriophage phi 29 DNA

The origins of replication of phi 29 DNA have been studied by analyzing the activity as templates in the phi 29 in vitro replication system of E. coli recombinant plasmids and M13 derivatives containing phi 29 DNA terminal sequences. Plasmid pITR, containing the 6 bp long inverted terminal repeat of phi 29 DNA, was shown to be essentially inactive. The analysis of a series of deletion derivatives of plasmid pID13, that contains the 73 and 269 bp from the left and right phi 29 DNA ends, respectively, indicated that the minimal origins of replication are comprised within the mutagenesis at these sequences was carried out. Changes of the second or third A into a C completely abolished the template activity. In the case of changes at position from 4 to 12, only 3 out of 14 mutations reduced the template activity; these 3 mutations were double changes and 2 of them affected the inverted terminal repeat. The results suggest that the sequence requirement at the end-proximal region of the origin of replication is more strict than that at the distal region.

The effect of temperature on immunoreactive glucagon plasma level in carp Cyprinus carpio

Plasma immunoreactive glucagon levels (IRG), plasma glucose levels and brain and liver glycogen concentrations were analyzed in carp (adapted to 15 degrees C) subjected to short-term temperature changes (1.6 or 11 h, at 5 degrees C or 28 degrees C, respectively) and to long-term temperature changes (21 months at 28 degrees C). The high temperature (28 degrees C) produced significant increases in IRG in both short and long-term experiments. Brain glycogen also decreased in both experiments whereas liver glycogen only changed in the long-term experiment. Low temperatures did not provoke any changes either in IRG or in liver glycogen, whereas brain glycogen decreased in the 1 h exposure. In short, under these conditions in carp, IRG did not respond to low temperature but could play an important role in high temperature acclimation.

Seasonal variations of insulin and some metabolites in dogfish plasma, Scyliorhinus canicula, L

Plasma levels in insulin, glucose, ketone bodies, and lactate were analyzed during a 1-year period in the lesser spotted dogfish (Scyliorhinus canicula) in captivity. Plasma insulin levels fluctuated similarly for both sexes. The highest insulin levels were found during late prespawning (from January to March) and another increase was observed during the active feeding period (September and October). During the spawning period, insulin decreased and in the postspawning period the lowest values were reached. Glucose, however, showed a different trend. It was at a minimum in late prespawning and it reached its highest values in postspawning. It decreased again in September and October. Plasma ketone body levels were highest in late prespawning and could be considered as an alternative energy source for this hypoglycemic period. In the summer months plasma lactate levels rose, with maximum levels occurring in July.

Effect of NH4+ ions on phi 29 DNA-protein p3 replication: formation of a complex between the terminal protein and the DNA polymerase

Ammonium ions stimulated the formation of the phi diameter 29 protein p3-dAMP initiation complex by decreasing the Km value for dATP in a purified system containing the viral terminal protein p3, the viral DNA polymerase p2, and the phi 29 DNA-protein p3 complex as a template. In addition, NH4+ ions stimulated the amount of p3-dAMP complex elongation and increased by about twofold the rate of elongation. The stimulatory effect of NH4+ ions on in vitro phi 29 DNA replication is probably related to the formation of a stable complex between the terminal protein and the DNA polymerase, which was detected only in the presence of NH4+ ions.

Annual cycle of plasma insulin and glucose of sea bass.Dicentrarchus labrax, L

Annual plasma insulin and glucose cycles were studied inDicentrarchus labrax maintained in either seawater (37.8‰) or brackish water (3.5‰). In both media, the highest insulin levels were found during the prespawning period (August-November) coincident to increases in weight and a decrease in plasma glucose. During spawning (December-April) and postspawning (May-July) periods, the decrease in insulin occurred at the same time as a reduction in growth and an increase of plasma glucose. Temperature and salinity conditions impeded spawning in the brackish water group, in which a minor weight loss was regained more quickly than in the sea water group; insulin levels were also higher.

Diclofenac versus dipyrone in acute renal colic: a double-blind controlled trial

A randomized, double-blind clinical trial in 50 patients was done to compare the efficacy and tolerance of single doses of intramuscular diclofenac 75 mg and dipyrone 2 g in acute renal colic. Both drugs were equally effective, but diclofenac was better in terms of complete relief of pain. Vital signs were affected according to the stress and pain.

Signals in the phi 29 DNA-terminal protein template for the initiation of phage phi 29 DNA replication

The protein-free terminal fragments HindIII B and L, from the left and right ends of phi 29 DNA, respectively, but not internal fragments of similar size, were active as templates in the formation of the p3-dAMP initiation complex in an in vitro system containing purified phi 29 terminal protein p3 and DNA polymerase p2, although the activity was lower than that obtained with the phi 29 DNA-p3 complex. These results indicate the existence of specific sequences at the ends of phi 29 DNA that allow the initiation of phi 29 DNA replication. The template activity of the protein-free terminal fragments was size dependent. The protein-free single strands of the HindIII L fragment were much less active than the corresponding double-stranded fragment. Terminal protein-DNA complexes of phages PZA and phi 15, with a terminal protein closely related to the phi 29 protein p3, were more active as templates in the initiation reaction with the purified phi 29 proteins than the corresponding protein-free DNAs, as it happens in the case of phi 29. However, the terminal protein-DNA complexes of phages Nf, B103, and GA-1, with a terminal protein less related or unrelated to the phi 29 protein p3, were essentially inactive and became active after removal of the parental terminal protein. These results strongly suggest that the parental terminal protein is the major signal in the template for the initiation of phi 29 DNA replication.

Replication of phage phi 29 DNA in vitro: role of the viral protein p6 in initiation and elongation

The phi 29 protein p6 stimulates the formation of the protein p3-dAMP initiation complex when added to a minimal system containing the terminal protein p3, the phi 29 DNA polymerase p2 and phi 29 DNA-protein p3 complex, by decreasing about 5 fold the Km value for dATP. In addition, protein p6 stimulates elongation of the p3-dAMP initiation complex. Whereas the effect of protein p6 on initiation is similar with protein p3-containing fragments from the right or left phi 29 DNA ends, the stimulation of elongation is higher with the right than with the left phi 29 DNA terminal fragment, suggesting DNA sequence specificity. The stimulation by protein p6 of the initiation and elongation steps of phi 29 DNA replication does not require the presence of the parental protein p3 at the phi 29 DNA ends. No effect of protein p6 was obtained on the elongation of the template-primer poly(dT)-(dA) 12-18 by the phi 29 DNA polymerase.

Cloning and template activity of the origins of replication of phage phi 29 DNA

A 73-bp fragment from the left end of phi 29 DNA and a 269-bp fragment from the right end have been cloned in plasmids pPLc28 and pKK223-3, respectively, after removal of the terminal protein p3 by treatment with piperidine. In addition, the 73- and 269-bp fragments were cloned together in plasmid pKK223-3 in such a way that the two termini of phi 29 DNA were joined. Treatment of the latter recombinant plasmid with AhaIII releases several fragments, two of which contain the phi 29 DNA terminal sequences at the DNA end. These two fragments initiated replication specifically at the ends of the DNA giving rise to the formation of the p3-dAMP complex. The activity was about 15% of that obtained with phi 29 DNA-protein p3. All remaining recombinant plasmids were essentially inactive when tested as templates either in circular form or after cutting in such a way that placed the origin of phi 29 DNA replication close but not at the DNA end.