Immunological properties of a DNA plasmid encoding a chimeric protein of herpes simplex virus type 2 glycoprotein B and glycoprotein D

A DNA plasmid containing a chimeric sequence encoding both herpes simplex virus type 2 (HSV-2) glycoprotein B (gB) and glycoprotein D (gD) external domains (pcgDB) was used to immunize BALB/c mice against genital HSV-2 infection. To determine the efficacy of this vaccine, groups of mice immunized with the pcgDB plasmid were compared with animals immunized with plasmids corresponding to the individual proteins (pcgBt or pcgDt), administered separately or in combination (pcgBt + pcgDt). We studied the response of the different mouse groups to viral challenge by analyzing clinical disease (vaginitis), serum antibody levels, as well as lymphoproliferative responses and cytokine production by spleen cells. Increased IFN-gamma levels correlated with prolonged survival in mice immunized with the plasmid pcgDB, relative to mice immunized with plasmids coding for the individual proteins alone or in combination. Our results show that immunization with the plasmid encoding the chimeric protein is advantageous over separate proteins. These findings may have important implications for the development of multivalent DNA vaccines against HSV and other complex pathogens.

Experimental vertical transmission of Piscirickettsia salmonis and in vitro study of attachment and mode of entrance into the fish ovum

Piscirickettsia salmonis is a pathogenic bacterial agent causing septicaemic disease in salmon. Since its isolation in Chile in 1989, P. salmonis has continually produced high mortality rates in salmon farms. Little information exists regarding the mechanisms of vertical transmission of this pathogen. Experimental vertical transmission was established in the present study by inoculation of male and female rainbow trout broodstock with P. salmonis. The bacterium was subsequently detected using indirect immunofluorescence in milt and coelomic fluid of the majority of inoculated broodstock (14/15). Bacteria were detected in the fry when 1 or both parents were inoculated, although none of the infected fry presented signs of the disease. P. salmonis was also detected in progeny obtained through fertilisation ova from non-inoculated females incubated in a medium containing a bacterial suspension, demonstrating transmission during the process of fertilisation. Ova infected in vitro were examined at sample periods from 30 s to 60 min using scanning electron microscopy. This demonstrated that the bacterium attaches to the ova by means of membrane extensions, structures which we have called 'piscirickettsial attachment complex' (PAC) and which would allow later penetration into the ovum.

[Primary care physicians' and patients' degree of satisfaction with a new respiratory medicine health care program]

BACKGROUND

No ideal model for coordinating primary care and specialized respiratory medicine has been established.

OBJECTIVE

To evaluate primary care physicians' and patients' degree of satisfaction with a new program for coordinating respiratory medicine and primary care.

METHOD

A questionnaire survey of the level of satisfaction with a program combining consultation and direct patient care. The study was carried out at a primary care facility whose staff comprised 31 general practitioners. The respiratory medicine staff consisted of one physician and two nurses from the reference hospital. A questionnaire to determine the physicians' and patients' satisfaction with the program asked for a) overall evaluation on a scale of 0 to 10; b) evaluation on a scale naming five levels from "very bad" to "very good", and c) comparison of the new program with previous ones.

RESULTS

One thousand one hundred seventy patients were seen in 12 months; 663 (57%) received a first visit, 400 (34%) received a second visit, and 107 (9%) received emergency care. The level of satisfaction was 7.8 (1.2) among physicians and 8.7 (1.5) among patients (p = 0.030); 97% of the physicians and 94% of the patients described the program as "very good" or "good". According to 100% of the physicians and 64% of the patients, the new program was better than the old one (p = 0.110).

CONCLUSIONS

The coordinated care plan proposed is accepted by most physicians and patients and uses primary respiratory medicine resources more efficiently.

Impact of meningococcal vaccination with combined serogroups A and C polysaccharide vaccine on carriage of Neisseria meningitidis C

Two studies of meningococcal carriage state were carried out in Galicia (Spain) before and after a mass vaccination campaign between December 1996 and January 1997 against Neisseria meningitidis serogroup C with meningococcal serogroups A and C polysaccharide vaccine. The studies covered two areas with different incidence rates of meningococcal disease in 1996 (high and low incidence). Carriage rates of serogroup C showed a decrease in both areas, 47 and 65 % respectively, before and after the vaccination. Results showed a decrease in carrier state in the age groups 10-14- and 15-19-year-olds, but not in the 5-9-year-olds. These results demonstrate the effect of immunization on the reduction of the carriage state.

Tolerance of a cluster schedule on the treatment of seasonal allergic respiratory disease with pollen extracts quantified in mass units

In order to evaluate the tolerance of a cluster schedule on specific immunotherapy (SIT), 306 patients were included in a multicenter study. The patients were suffering from rhinoconjunctivitis with/without asthma, caused by sensitization to olive and/or grass pollen. SIT was administered subcutaneously according to a cluster schedule in which the maintenance dose is reached after four visits (3 weeks). The extracts were biologically standardized with major allergens quantified in mass units. Local reactions appeared in 7.2% of the patients and 1.3% of the doses. Systemic reactions (SR) were recorded in 1.2% of the doses administered to 9.5% of the patients. No anaphylactic shock was registered, and all the SR responded fully and rapidly to treatment. There was no difference in SR according to diagnosis or allergen extract used. The majority of SR occurred with the administration of vial of higher concentration (Vial 2: 7 SR (22%), Vial 3: 32 SR (78%), p < 0.05). Of the 32 SR recorded with Vial 3, 13 (41%) were immediate, with no existing association between dose administered and appearance of SR. However, of the 18 delayed SR (56%), 14 occurred after the administration of the first two doses of Vial 3 and four occurred after administration of the second two doses (78% vs 22%, p < 0.05). On the other hand, this regime realized an important saving in cost and time compared to the conventional schedule (1581 fewer doses and 2754 fewer visits were necessary to reach the optimal dose). Considering all these factors, the clinical profile of the proposed regime may be qualified as good. However, future studies are necessary in order to better adjust the schedule to avoid the delayed SR that occurred after the administration of the first two doses of Vial 3.

Plant chromosomal HMGB proteins efficiently promote the bacterial site-specific beta-mediated recombination in vitro and in vivo

In the presence of an accessory DNA bending protein, the bacterial site-specific beta recombinase catalyzes resolution and DNA inversion. Five different maize high mobility group B (HMGB) proteins were examined for their potential to facilitate beta recombination in vitro using DNA substrates with different intervening distances (73-913 bp) between two directly oriented recombination (six) sites. All analyzed HMGB proteins (HMGB1 to HMGB5) could promote beta recombination, but depending on the DNA substrate with different efficiencies. The HMGB1 protein displayed an activity comparable to that of the natural promoting protein Hbsu, whereas the other HMGB proteins were less effective. Phosphorylation of the HMGB1 protein resulted in an increased efficiency of HMGB1 to promote beta recombination. Analyses of DNA substrates with closely spaced six sites demonstrated that in the presence of HMGB1 the recombination rate was correlated to the distance between the six sites, but independent of the helical orientation of the six sites. Using a Bacillus subtilis strain defective in Hbsu, the coexpression of beta recombinase and HMGB1 (or a truncated HMGB1 derivative) revealed that a plant HMG-box domain protein is sufficient for assisting beta to catalyze recombination in vivo. Our results using beta recombination as a model system suggest that the various plant HMGB proteins (and their posttranslationally modified versions) have the potential of forming a repertoire of different DNA structures, which is compatible with the idea that the HMGB proteins can act as architectural factors in a variety of nucleoprotein structures.

Impact of the recommendations made by Spanish Club for the Study of Helicobacter pylori on eradication indications

AIM

A Spanish Consensus Conference had been arranged by the Spanish Club for the Study of Helicobacter pylori to encourage the use of eradication regimens in appropriate indications. The aim of our study was to assess whether the publication of these recommendations in November 1999 induced a change on the indications of eradication in the referring primary care district.

METHOD

Patients who had undergone Helicobacter pylori eradication therapy indicated by a gastroenterologist and referred to perform the 13C-labelled marked urea breath test were evaluated. Indications of eradication therapy were analysed and divided in: a) use of Conference recommended procedures (duodenal or gastric ulcer, erosive duodenitis, gastric MALT lymphoma and after resection of gastric adenocarcinoma); and b) other procedures not included in the recommendations (the rest). Indications established during former and latter years of publication of the Club's recommendations were compared.

RESULTS

A total of 659 established eradications in 1999 against 537 in 2000, were studied. Regarding established eradications in 1999, 418 out of 659 (63%) followed the recommendations made by the Spanish Club, while 241 (37%) did not. In 2000, the proportion of eradication therapy administered using the recommendations made by the Spanish Club was similar to previous year: 338 (63%) followed the recommendations, against 199 (37%) that did not (p = not significant). In both years, considering those indications not recommended, patients either with superficial chronic gastritis with or without dyspepsia or with gastrooesophageal reflux disease were the main disorders to indicate eradication therapy.

CONCLUSIONS

The recommendations of the Spanish Helicobacter pylori Study Club have not triggered a significant change after their publication on the indications for Helicobacter pylori eradication therapy in the setting studied.

Effects of pregnancy on insulin receptor in liver, skeletal muscle and adipose tissue of rats

The mechanism responsible for insulin resistance during pregnancy remains unclear. Considerable evidence indicates that the insulin receptor plays an important role in insulin sensitivity. It seems possible that the hormonal milieu during gestation could have an effect on the insulin receptor. In the present study, measurements of tyrosine phosphorylation and protein content of the insulin receptor and expression of its gene in liver, skeletal muscle and adipose tissue indicate that during pregnancy significant changes occur in these parameters. We found that at the end of early gestation (day 10), muscle and adipose tissue are very sensitive to insulin action because the amount, phosphorylation and gene expression of insulin receptor is higher than in late gestation (days 15-20), while the tissue which is most sensitive to insulin action in late gestation is the liver. Our hypothesis is that these results are connected with changes in the concentrations of estradiol and progesterone observed during pregnancy. In conclusion, our previous and present findings seem to demonstrate that the different concentrations of gestational hormones play an important role in insulin sensitivity in this period and that each tissue responds in the most appropriate manner to guarantee the gestation in its entirety.

Rhodobacter sphaeroides LexA has dual activity: optimising and repressing recA gene transcription

Transcription of the Rhodobacter sphaeroides recA promoter (P(recA)) is induced upon DNA damage in a lexA-dependent manner. In vivo experiments demonstrate that LexA protein represses and might also activate transcription of P(recA). Purified R.sphaeroides LexA protein specifically binds the SOS boxes located within the P(recA) region. In vitro transcription analysis, using Escherichia coli RNA polymerase (RNAP), indicated that the presence of LexA may stimulate and repress transcription of P(recA). EMSA and DNase I footprinting experiments show that LexA and RNAP can bind simultaneously to P(recA). At low LexA concentrations it enhances RNAP binding to P(recA), stimulates open complex formation and strand separation beyond the transcription start site. At high LexA concentrations, however, RNAP-promoted strand separation is not observed beyond the +5 region. LexA might repress transcription by interfering with the clearance process instead of blocking the access of RNAP to the promoter region. Based on these findings we propose that the R.sphaeroides LexA protein performs fine tuning of the SOS response, which might provide a physiological advantage by enhancing transcription of SOS genes and delaying full activation of the response.

Effect of treatment with different doses of 17-beta-estradiol on the insulin receptor

The mechanism for the development of insulin resistance in normal pregnancy is complex and is associated with serum levels of sex hormones. However, the influence of these hormones on the early steps of insulin action has not been extensively studied, although the potentially beneficial effect of estradiol on glucose homeostasis has been reported. In this paper, we attempted to determine the effect of 17-beta-estradiol on the insulin receptor of ovariectomized rats treated with different doses of hormones. Our results showed a tissue-dependent response to estradiol. We found that low doses of estradiol increased the amount of insulin receptors in liver and muscle on days 6 and 11 of treatment but not in adipose tissue, and after 16 days only the muscle responsed in this way. On the other hand, high doses of estradiol significantly decreased the amount of insulin receptors, at least in muscle and adipose tissue. We believe that the low concentrations of 17-beta-estradiol (similar to early pregnancy) could be responsible for the increase in insulin sensitivity by increasing the amount of insulin receptors in peripheral tissues. When the hormone levels were high (similar to late pregnancy) the amount of insulin receptors decreased in peripheral tissues, and insulin sensitivity is diminished just as in late pregnancy. The specific molecular mechanism for this action is as yet unknown.

Effect of the recU suppressors sms and subA on DNA repair and homologous recombination in Bacillus subtilis

In Bacillus subtilis, mutant alleles of the genes sms and subA partially suppress the recombination phenotype of recU cells. When present in an otherwise Rec(+) strain, Delta sms and Delta subA alleles render cells slightly sensitive to DNA-damaging agents, and impair chromosomal transformation (3- to 10-fold reduction), but do not affect plasmid transformation (less than 1.5-fold reduction). The Delta sms and Delta subA alleles were introduced into rec-deficient strains representative of the epistatic groups alpha (recF strain), beta (addA addB), gamma (recH), epsilon (recB, Delta recU and recD strains) and zeta (Delta recS). Both the Delta sms and Delta subA mutations were found to increase sensitivity to DNA-damaging agents in recF, Delta recS and addAB cells. In contrast, the Delta sms mutations decreased the sensitivity of recB, Delta recU, recD and recH cells, and the Delta subA mutation decreased the sensitivity of recB and Delta recU cells to DNA-damaging agents. Functions classified within the epistatic groups alpha, epsilon and zeta are required for intramolecular recombination, measured as plasmid transformation. The Delta sms and Delta subA mutations, which partially suppressed the recombinational repair phenotype of mutants for functions within epistatic group epsilon, enhanced plasmid transformation of recU (recB, recD) and recS cells by 10- to 20-fold. In the absence of the proteins Sms and SubA, the recombination machinery is apparently redirected towards (an) alternative pathway(s). Furthermore, the shared ability of the Delta sms and Delta subA mutations to act as indirect suppressors of recB, recU and recD mutations supports the classification of the recBUD genes within epistatic group epsilon.

Nuclear maturation inducers in Bufo arenarum oocytes

The present study analyses the effect of dihydrotestosterone (DHT) and mammalian insulin on the nuclear maturation of Bufo arenarum oocytes under in vitro conditions. The response of fully grown follicle oocytes to DHT, shown by germinal vesicle breakdown (GVBD), occurred in a manner dependent on dose, time and sexual cycle period. The highest oocyte sensitivity to the hormone appeared during the breeding period, a fact evinced by high GVBD percentages after short incubation periods and at a low hormone concentrations. Insulin also proved effective in inducing nuclear maturation, although its action was only visible at high concentrations and after a long incubation period. The combination of insulin and steroid hormones (DHT or progesterone), both at subliminal doses, caused a noticeable potentiating synergism, resulting in a rapid and important increase in GVBD. Another effect of insulin was the acquisition by oocytes of steroid sensitivity during folliculogenesis.

Genetic recombination in Bacillus subtilis 168: effect of DeltahelD on DNA repair and homologous recombination

The B. subtilis DeltahelD allele rendered cells proficient in transformational recombination and moderately sensitive to methyl methanesulfonate when present in an otherwise Rec(+) strain. The DeltahelD allele was introduced into rec-deficient strains representative of the alpha (recF strain), beta (addA addB), gamma (recH), epsilon (DeltarecU), and zeta (DeltarecS) epistatic groups. The DeltahelD mutation increased the sensitivity to DNA-damaging agents of addAB, DeltarecU, and DeltarecS cells, did not affect the survival of recH cells, and decreased the sensitivity of recF cells. DeltahelD also partially suppressed the DNA repair phenotype of other mutations classified within the alpha epistatic group, namely the recL, DeltarecO, and recR mutations. The DeltahelD allele marginally reduced plasmid transformation (three- to sevenfold) of mutations classified within the alpha, beta, and gamma epistatic groups. Altogether, these data indicate that the loss of helicase IV might stabilize recombination repair intermediates formed in the absence of recFLOR and render recFLOR, addAB, and recH cells impaired in plasmid transformation.

[Compliance of antituberculosis therapy among ex-inmates in the Madrid area]

BACKGROUND

The inmate population is not a tight compartment without communication with the community but there is a flow of persons and thus of health problems. The high incidence of tuberculosis among inmates is therefore of concern for the Public Health System.

METHODS

The outcomes of antituberculosis treatment among ex-inmates released from prison in 1987 in the Madrid Area were evaluated and compared with those who remained in jail on treatment. Individuals who met the case definition of tuberculosis were included in the study. The outcome was defined as the individual status one year after the beginning of therapy. To determine the association between the study variables with outcome, odds ratios (OR) with their 95% confidence intervals were used. The Chi2 test was used to determine the statistical significance.

RESULTS

Differences between outcomes of individuals in the two groups were observed: 69.7% of inmates had completed their therapy compared with 20.5% of ex-inmates. Treatment had to be prolonged in 15.2% of inmates compared with 46.2% in ex-inmates. The only predictor associated with therapy completion one year after the beginning was imprisonment, as OR for not having completed therapy for ex-inmates was almost 13 times higher (OR=12.94; 95% IC, 3.38-13.10) than those in jail.

CONCLUSIONS

Special strategies should be developed that assure clinical cure of persons with factors related to non-compliance.

Hydrothermal synthesis and structural characterization of the (C(n)H(2n+6)N(2)[Mn(3)(HPO(3))4] (n = 3-8) new layered inorganic-organic hybrid manganese(II) phosphites. Crystal structure and spectroscopic and magnetic properties of (C(3)H(12)N(2)[Mn(3)(HPO(3))4]

The (C(n)H(2n+6)N(2))[Mn(3)(HPO(3))(4)] (n = 3-8) compounds have been prepared by hydrothermal synthesis and characterized by X-ray diffraction data and spectroscopic techniques. The crystal structure of (C(3)H(12)N(2))[Mn(3)(HPO(3))(4)] has been solved from single-crystal X-ray diffraction. The unit-cell parameters are a = 9.502(1), b = 5.472(1), c = 14.523(4) A, beta = 95.01(3) degrees, monoclinic, C2/m, with Z = 2. The compound shows a layered structure stacked along the c-axis with the alkyldiammonium cations placed in the interlayer space. The sheets are formed by Mn(3)O(12) trimer units extended in the ab-plane and connected by (HPO(3))(2-) anions. The study of the (C(n)H(2n+6)N(2))[Mn(3)(HPO(3))(4)] (n = 4-8) phases by X-ray powder diffraction indicates an isotype relation with the propanediammonium compound. The Dq and Racah parameters calculated for (C(3)H(12)N(2))[Mn(3)(HPO(3))(4)] are Dq = 880, B = 660 and C = 3610 cm(-1). The ESR spectra show isotropic signals with a g-value of 2.008. Magnetic measurements indicate the presence of antiferromagnetic interactions inside the [Mn(3)(HPO(3))(4)](2-) sheets. The J/K value has been estimated to be -15 K by considering that the system behaves like an isolated trimer at high temperatures.

Effect of treatment with different doses of 17-beta-estradiol on insulin receptor substrate-1

CONTEXT

Ovarian hormones modulate insulin sensitivity, but their exact role remains unclear.

OBJECTIVE

We tried to determine whether different doses of 17-beta-estradiol cause changes in the regulation of insulin receptor substrate (IRS-1) levels, and if so, the possible implications in insulin sensitivity.

DESIGN

Ovariectomized rats were treated with different doses of 17-beta-estradiol at 6, 11 and 16 days.

MAIN OUTCOME MEASURES

Immunoprecipitation and Western blotting for IRS-1 were performed in different tissues.

RESULTS

We found that estradiol treatment has an influence on the amount of IRS-1 but that it acts in different ways depending on the tissue studied, on the length of treatment, and on the doses employed.

CONCLUSIONS

Our results suggest that low concentrations of 17-beta-estradiol could be responsible for the upregulation of insulin receptor substrate 1, increasing insulin sensitivity in muscle and adipose tissue. However, insulin receptor substrate 1 is downregulated with high concentrations of 17-beta-estradiol, thus these high hormone plasma levels could favour insulin resistance in peripheral tissues. The role of 17-beta-estradiol seems to modulate insulin receptor substrate 1 levels in insulin dependent tissues, but in a different manner in each tissue. These novel findings are important for improving knowledge about the possible risk for insulin resistance in women taking oral contraceptives or receiving hormone replacement therapy at menopause.

Cal-B-catalyzed alkoxycarbonylation of a-ring stereoisomeric synthons of 1alpha,25-dihydroxyvitamin D3 and 1alpha,25-dihydroxy-19-nor-previtamin D3: a comparative study. first regioselective chemoenzymatic synthesis of 19-nor-A-ring carbonates

A comparative study of alkoxycarbonylation processes of both 19-nor-A-ring and A-ring stereoisomers of 1alpha,25-dihydroxyvitamin D3 analogues catalyzed by Candida antarctica lipase B (CAL-B) has been described. The presence of the methyl group in the A-ring at C-2, as in 3-6, has a determining role in the regioselectivity of the biocatalysis, mainly allowing the hydroxyl group at C-5 position to react. For the 19-nor-A-ring stereoisomers 7-10, which lack the C-2 methyl group, the configurations at C-3 and C-5 have a high influence in the selectivity exhibited by CAL-B. Thus, each couple of enantiomers showed opposing regioselectivities depending on the C-3 configuration. When C-3 possesses an (S)-configuration, enzymatic alkoxycarbonylations took place at the C-5-(R) or C-5-(S) hydroxyl groups. However, if the chiral centers at C-3 are (R), CAL-B alkoxycarbonylated the C-3-(R) hydroxyl group independently of the configuration at C-5. The corresponding carbonates are useful A-ring precursors of 1alpha,25-dihydroxyvitamin D3 analogues, selectively modified at the C-1 or C-3 positions. In addition, an improved synthesis of cis A-ring synthons 5 and 6 is described using a Mitsunobu methodology.

The essential HupB and HupN proteins of Pseudomonas putida provide redundant and nonspecific DNA-bending functions

A protein mixture containing two major components able to catalyze a beta-recombination reaction requiring nonspecific DNA bending was obtained by fractionation of a Pseudomonas putida extract. N-terminal sequence analysis and genomic data base searches identified the major component as an analogue of HupB of Pseudomonas aeruginosa and Escherichia coli, encoding one HU protein variant. The minor component of the fraction, termed HupN, was divergent enough from HupB to predict a separate DNA-bending competence. The determinants of the two proteins were cloned and hyperexpressed, and the gene products were purified. Their activities were examined in vitro in beta-recombination assays and in vivo by complementation of the Hbsu function of Bacillus subtilis. HupB and HupN were equally efficient in all tests, suggesting that they are independent and functionally redundant DNA bending proteins. This was reflected in the maintenance of in vivo activity of the final sigma54 Ps promoter of the toluene degradation plasmid, TOL, which requires facilitated DNA bending, in DeltahupB or DeltahupN strains. However, hupB/hupN double mutants were not viable. It is suggested that the requirement for protein-facilitated DNA bending is met in P. putida by two independent proteins that ensure an adequate supply of an essential cellular activity.