C282Y and H63D mutations of the haemochromatosis gene in patients with iron overload

OBJECTIVE

To determine the relevance of C282Y and H63D mutations of HEF gene in patients with iron overload.

PATIENTS AND METHODS

Patients with iron overload referred to our Liver Unit were included in the study. The association of mutations to different diagnosis and their impact on the severity of the hepatopathy were explored. Sensitivity, specificity and positive and negative predictive values of mutations for the diagnosis of haemochromatosis were determined.

RESULTS

The study included 78 patients with iron overload. The control group included 21 patients of similar age and sex ratio without iron overload nor hepatopathy. Twenty three patients had haemochromatosis, 22 alcoholic liver disease and 33 other diseases unrelated to iron metabolism. Seventy three per cent of patients with haemochromatosis were homozygous for the C282Y mutation. All the C282Y homozygous subjects had also haemochromatosis. Fifty three per cent of patients with alcoholic hepatopathy had some kind of mutation. This has been also observed in 70% of patients with iron-unrelated diseases. Such percentage was significantly greater than in the control group (24% with H63D mutation). C282Y homozygosity in patients with iron overload had a sensitivity of 73.9%, a specificity of 100%, a positive predictive value of 100% and a negative predictive value of 89.6%.

CONCLUSIONS

In our population, as in all the Western countries, haemochromatosis is mainly associated to homozygous C282Y mutation. The high frequency of mutations in patients with iron overload and without haemochromatosis suggests the involvement of such mutations in iron overload.

Growth Rate of the microalga Tetraselmis suecica changes the biochemical composition of Artemia species

The impact of different microalgal semicontinuous cultures on growth and biochemical composition in the next link of the food chain was tested using the filter feeder Artemia species as a model. The marine microalga Tetraselmis suecica was cultured semicontinuously with renewal rates between 10% and 50% and used to feed Artemia. Microalgal cultures maintained with a low renewal rate that had biochemical composition similar to that of the stationary-phase cultures commonly used in aquaculture produced poor growth and survival and low food-conversion efficiency compared to cultures maintained with a high renewal rate. Changes in the renewal rate in microalgal cultures also resulted in important changes in the gross biochemical composition of the filter feeder. The gross biochemical composition of the Artemia resembled that of the microalgae used as food except for total lipid content. The percentage of protein in the organic fraction of Artemia increased from 45% to 65% of the organic weight with increasing renewal rates in the microalgal cultures, while the carbohydrate percentage decreased under the same conditions. Higher renewal rates resulted in higher lipid percentages in the microalga, but in Artemia the percentage of lipids decreased from 19% of the organic weight with a renewal rate of 10%, to 13% with a renewal rate of 50%. The percentage of all polyunsaturated fatty acids in Artemia, including 20:5n-3, increased slightly with increasing renewal rates in the microalgal cultures. Results emphasize the importance of controlling microalgal nutritional value for the success of aquaculture food chains in which filter feeders are involved.

Dramatic decline of serogroup C meningococcal disease incidence in Catalonia (Spain) 24 months after a mass vaccination programme of children and young people

STUDY OBJECTIVES

The objective of this study was to evaluate the effectiveness of a mass vaccination programme carried out in Catalonia (Spain) in the last quarter of 1997 in response to an upsurge of serogroup C meningococcal disease (SCMD).

DESIGN

Vaccination coverage in the 18 month to 19 years age group was investigated by means of a specific vaccination register. Vaccination effectiveness was calculated using the prospective cohort method. Cases of SCMD were identified on the basis of compulsory reporting and microbiological notification by hospital laboratories. Vaccination histories were investigated in all cases. Unadjusted and age adjusted vaccination effectiveness referred to the time of vaccination and the corresponding 95% confidence intervals (CI) were estimated at 6, 12, 18 and 24 months of follow up.

SETTING

All population aged 18 months to 19 years of Catalonia.

MAIN RESULTS

A total of seven cases of SCMD were detected at six months of follow up (one in the vaccinated cohort), 12 cases at 12 months (one in the vaccinated cohort), 19 cases at 18 months (two in the vaccinated cohort) and 24 at 24 months (two in the vaccinated cohort). The age adjusted effectiveness was 84% (95%CI 30, 97) at six months, 92% (95%CI 63, 98) at 12 months, 92% (95% CI 71, 98) at 18 months and 94% (95%CI 78, 98) at 24 months. In the target population, cases have been reduced by more than two thirds (68%) two years after the vaccination programme. In the total population the reduction was 43%.

CONCLUSION

Vaccination effectiveness has been high in Catalonia, with a dramatic reduction in disease incidence in the vaccinated cohort accompanied by a relevant reduction in the overall population. Given that vaccination coverage was only 54.6%, it may be supposed that this vaccination effectiveness is attributable, in part, to the herd immunity conferred by the vaccine.

[Creatine kinase increases after coronary interventions]

INTRODUCTION AND OBJECTIVES

Percutaneous revascularization has led to an important change in the treatment of patients with symptomatic ischemic heart disease in recent years. There is controversy concerning the incidence and prognostic significance of postprocedural increases in creatine kinase. The aim of this study was to assess the incidence of these elevations and the related factors and to observe the prognosis of patients with and without creatin kinase elevations.

METHODS

We reviewed 447 patients in whom an angioplasty was done in our department from January 1997 to June 1998, excluding 138 patients with myocardial infarction in the previous four days or unsuccessful angioplasty. Creatine kinase was measured in all patients at 0, 4, 8 and 24 hours after angioplasty. We analyzed the incidence of elevated levels of creatine kinase following coronary surgery and the characteristics of the patients in comparison with a control group made up of patients who, at a similar time had undergone a similar angioplasty procedure including, a similar vessel and type of lesion, and equivalent left ventricular function but without elevated serum levels of creatine kinase. Major adverse coronary events were defined as: cardiac death, nonfatal myocardial infarction, new revascularization and unstable angina in which hospitalization was required.

RESULTS

Out of 309 patients studied, an elevation in creatine kinase was observed in 24 patients (7.7%). Complications related to the procedure were found in 50% of these elevations, most of which involved side branch occlusion. There were no differences with respect to the demographical or anatomical characteristics of the lesions in the groups studied. During the follow-up of 9.5 months, complications were observed in 37.5% of the group of patients with elevated creatine kinase levels and in 20% of the control group, but this difference did not achieve statistical significance.

CONCLUSIONS

Creatine kinase elevations are produced in 7.7% of the patients after coronary angioplasty. Complications related to the procedure were observed in 50% of the cases, most being side branch occlusion and no complications were seen in the remaining patients. Continuous measurement of creatine kinase after angioplasty shows a low sensitivity for detecting complications during follow-up. New, more sensitive and specific cardiac markers, such as troponin, could define this group of patients.

Vascular reactivity to angiotensin II and eicosanoid production in the human placenta from term and preterm pregnancy

Isolated human placental cotyledons from normal term (37-40 weeks of gestation) and preterm (26-36 weeks of gestation) labor were perfused in vitro, and the effect of angiotensin II (ANG II) and its interaction with prostanoids was measured. In the preterm group, ANG II caused greater maximal increases in perfusion pressure than in normal term pregnancies without affecting sensitivity. Also, preparations from normal term pregnancies showed a marked development of tachyphylaxis compared to placentae from preterm pregnancies. Indomethacin (10(-6) M) increased the maximum pressor response to ANG II by 33.6% in normal term, however, in preterm placentas a 39.2% reduction was observed. Infused ANG II 10(-6) M) decreased the concentrations of thromboxane B(2) and 6-keto-PGF(1alpha) in both pregnancy groups, but this effect was not statistically different from the baseline values. In the current study, we show that the placenta of preterm pregnancies in basal conditions produce 7.6 times as much thromboxane as the normal term placenta (2,800+/-470 vs. 366.5+/-62 pg/min, respectively), without significant change in prostacyclin levels (preterm 88.6+/-11.0 vs. Term 100.6+/-30.7 pg/min). These observations provide evidence that the contribution of basally released thromboxane from placental tissue appears to contribute to abnormalities in the regulation of fetoplacental hemodynamics in premature pregnancies.

Estimation of microsatellite mutation rates in Drosophila melanogaster

Microsatellite mutations were studied in a set of 175 mutation accumulation lines, all of them independently derived from a completely homozygous population of Drosophila melanogaster and maintained under strong inbreeding during 80 generations. We assayed 28 microsatellites and detected two mutations. One mutation consisted of a single addition of a dinucleotide repeat and the other was a deletion of five trinucleotide repeats. The average mutation rate was 5.1 x 10(-6), in full agreement with previous estimates from two different sets of mutation accumulation lines.

Hepatitis A and B in children and adolescents--what can we learn from Puglia (Italy) and Catalonia (Spain)?

Viral hepatitis remains a major contributor to the global disease burden. Mass immunisation strategies against hepatitis B have been adopted by more than 90 developing and industrialised countries. Countries with low hepatitis A endemicity are experiencing cyclical outbreaks and an epidemiological shift, with larger numbers of individuals at risk of infection at an older age, resulting in increased morbidity. The high cost of outbreaks in these countries has made immunisation strategies cost-effective. The development of a vaccine against hepatitis A and a combined vaccine against hepatitis A and hepatitis B offers potentially exciting opportunities for a preventative approach in areas of both low and high endemicity. Existing mass immunisation programmes against hepatitis B will facilitate the adoption of joint strategies illustrated by the examples of Puglia (Italy) and Catalonia (Spain).

Seroepidemiology of varicella-zoster virus infection in Catalonia (Spain). Rationale for universal vaccination programmes

With the aim of designing a strategy for vaccination against varicella-zoster virus (VZV), the results of a seroepidemiological survey on VZV infection carried out in a sample of the population of Catalonia are presented. Representative samples from schoolchildren (30 schools) and adults (97 municipal areas) were obtained by random cluster sampling. In the study, 883 children and 1253 adults were included. Age, gender, place of birth, place of residence, educational level and occupation were investigated in the study subjects. An ELISA test was used to measure varicella antibodies. The prevalence of varicella antibodies increased with age, being 85% in the 5-9 years age group, 92% in the 10-14 years age group, 94% in the 15-34 years age group and almost 100% in people over 35. No association was found between sociodemographic variables studied and prevalence levels of antibodies. These results suggest that the best vaccination strategy in Catalonia would be to add a temporary vaccination programme of pre-adolescents at 12 years to routine vaccination at 15 months.

Bioequivalence study of paracetamol tablets: in vitro-in vivo correlation

The bioequivalence of three chemically equivalent paracetamol generic Mexican products (500 mg tablets) was evaluated in 12 healthy volunteers using the American innovator product (Tylenol, McNeil, Fort Washington, PA), as the reference. Single oral doses of each product were administered at 1-week intervals using a 4 x 4 Latin square design balanced for the first residual effect. The total amount of paracetamol excreted in urine in 24 hr was taken as a measure of bioavailability. In addition, moment analysis was used to estimate in vitro mean dissolution time (MDT) from dissolution profiles obtained following the USP 23 dissolution test specified for paracetamol tablets and to estimate in vivo mean residence time (MRT) from urinary excretion data. Significant differences in the dissolution performance and in the cumulative amount of paracetamol excreted in urine up to 24 hr were observed when the data were analyzed by analysis of variance (ANOVA) (p < .05). Classical and Westlake 90% confidence limits, as well as the two-sided t test proposed by Schuirmann, and the Anderson-Hauck power analysis supported the final conclusion that only one of the three generic paracetamol products studied can be considered equivalent to the reference product Tylenol. A linear correlation between in vitro MDT and in vivo MRT was found.

Prevalence of Haemophilus influenzae pharyngeal carriers in the school population of Catalonia. Working Group on invasive disease caused by Haemophilus influenzae

The objective of this study was to determine the prevalence of healthy Haemophilus influenzae (Hi) pharyngeal carriers in a representative sample of the Catalonian school population, as well as the factors associated. A two-stage cluster sampling was carried out. Parents were given a questionnaire to collect information on sociodemographic and epidemiological variables. A pharyngeal swab was performed on children when informed consent was given by parents, and was cultured on chocolate agar with 260 microg/ml bacitracin. Of the 1212 children studied, 316 (26%) H. influenzae carriers were detected: 5 (0.4%) serotype b, 1 (0.08%) serotype c, 6 (0.5%) serotype e, 5 (0.4%) serotype f, and 299 (24.7%) non-typable. Age, gender and geographical location were the only variables associated with H. influenzae carrier status. The prevalence of non-typable H. influenzae carriers was similar to that of studies carried out in other countries, while that of serotype b carriers was similar to the remainder of H. influenzae capsulates, and lower than that described in previous studies. These data are in accordance with the low incidence of the disease observed in our context, although the possibility that the vaccine coverage may have affected the results of this study cannot be dismissed.

[Norwalk virus-like food poisoning after eating oysters]

BACKGROUND

The aim of this study was to conduct a clinical-epidemiological and microbiological investigation into an outbreak of food-borne disease due to the consumption of oysters.

PATIENTS AND METHODS

A historic cohort study was conducted into the consumption of 15 food items and clinical symptoms. The influence of each foodstuff was assessed by Mantel-Haenzel stratified relative risk (RRM-H) at 95% confidence intervals, and was confirmed by dose-response analysis with a chi 2 test tendency. We investigated sample stools from 5 patients and 2 food-handlers.

RESULTS

The overall attack rate was 38.0% (19/50). The median period of incubation was 39.0 h (maxim 62 and minimum 3 h). The symptoms were: fever 17.6% (3/17), diarrhoea 57.9% (11/19), vomits 84.2% (16/19), nausea 89.5% (17/19) and abdominal pain 89.5% (17/19). In stratified analysis, the Mantel-Haenzel method revealed a statistically risk for oysters (RRM-H = 3.3; IC 95%: 1.1-8.7), while the RRM-H value for sea snails was not significant (RRM-H = 2.8; IC 95%: 0.9-41.1). For oyster consumption, the dose-response test was statistically significant (p = 0.005). Examination by electron microscopy revealed small round structured viruses compatible with Norwalk-like virus. The oyster contamination was reported to the public health authority.

CONCLUSIONS

This research highlights the usefulness of dose-response analysis in presenting epidemiological evidence, reveals the potential role of oyster consumption in food-borne disease such us Norwalk-like virus and show the need for monitoring production centres and oyster beds in order to prevent further cases of contamination.

Changes in the seroepidemiology of hepatitis B infection in Catalonia 1989-1996

The objective of this study was to investigate the prevalence of hepatitis B markers in a representative sample of 2142 subjects in Catalonia, Spain, and to compare it with previous studies. Multiple logistical regression analysis was carried out to determine variables associated with the markers studied. The prevalence of anti-HBc and HBsAg was 9.1% and 1.2%, respectively. Male gender, urban habitat, birth place outside Catalonia and lower social class were associated with the presence of anti-HBc. Carrier status was only associated with male gender. Between 1989 and 1996 there was a decrease of 46% in the prevalence of serum HBV markers mainly in the 25-44 (P<0.0001) and 35-64 year (P=0.0002) age groups, in those born in Catalonia (P=0.003) and in those in the higher social classes (P<0.0001). These decreases can be explained by the improved socioeconomic conditions and, partially, by the routine pre-adolescent and risk group programmes of immunization.

[Adaptation of the clinician-administered rating scale for mania]

INTRODUCTION

There is no mania rating scale properly adapted in Spain, and it's a true problem in research.

METHODS

The adaptation process has been the following one: The authors start from CARS-M of Altman et al. First the carry out the translation and back translation which was revised by the author of the scale. Then they fullfill some previous training with video filming and lastly they apply the scale to a group of 24 patients.

RESULTS

The Clinician-Administered Rating Scale for Mania (CARS-M) shows good psychometric proprieties among those its internal consistency of the scale, the interobservers reliability, and the item-total correlation. These results are lightly worse in the psychoticism sub-scale.

CONCLUSIONS

This rating scale for mania show itself as a useful instrument in clinic and research.

Optimization of culture medium for the continuous cultivation of the microalga Haematococcus pluvialis

The freshwater microalga Haematococcus pluvialis is one of the best microbial sources of the carotenoid astaxanthin, but this microalga shows low growth rates and low final cell densities when cultured with traditional media. A single-variable optimization strategy was applied to 18 components of the culture media in order to maximize the productivity of vegetative cells of H. pluvialis in semicontinuous culture. The steady-state cell density obtained with the optimized culture medium at a daily volume exchange of 20% was 3.77 x 10(5) cells ml(-1), three times higher than the cell density obtained with Bold basal medium and with the initial formulation. The formulation of the optimal Haematococcus medium (OHM) is (in g l(-1)) KNO3 0.41, Na2HPO4 0.03, MgSO4 x 7H2O 0.246, CaCl2 x 2H2O 0.11, (in mg l(-1)) Fe(III)citrate x H2O 2.62, CoCl2 x 6H2O 0.011, CuSO4 x 5H2O 0.012, Cr2O3 0.075, MnCl2 x 4H2O 0.98, Na2MoO4 x 2H2O 0.12, SeO2 0.005 and (in microg l(-1)]) biotin 25, thiamine 17.5 and B12 15. Vanadium, iodine, boron and zinc were demonstrated to be non-essential for the growth of H. pluvialis. Higher steady-state cell densities were obtained by a three-fold increase of all nutrient concentrations but a high nitrate concentration remained in the culture medium under such conditions. The high cell productivities obtained with the new optimized medium can serve as a basis for the development of a two-stage technology for the production of astaxanthin from H. pluvialis.

Structural instability of 297 element in Drosophila melanogaster

297 element Southern pattern modifications previously detected in mutation accumulation lines of Drosophila melanogaster were further investigated by in situ hybridisation, Southern blotting with different combinations of genomic digest-probe, and PCR. Only one out of the nine pattern modifications studied could be interpreted as an excision and was detectable by in situ hybridisation to polytene chromosomes. Results were consistent with most pattern modifications being small rearrangements within the body of the element. In agreement with the existence of spontaneous rearrangements of this kind is the observation that many genomic copies of element 297 are defective and these are not limited to heterochromatin. These findings have important implications for the models of transposable element (TE) number regulation as well as for the study of genome evolution.

Prevalence of Haemophilus influenzae carriers in the Catalan preschool population. Working Group on Invasive Disease Caused by Haemophilus influenzae

This study was designed to determine the prevalence of healthy Haemophilus influenzae carriers in a random sample of the preschool population in Catalonia. Oropharyngeal swabs were collected and cultured on chocolate agar supplemented with 260 microg/ml of bacitracin. Four hundred two of the 734 (54.8%) children studied were detected as Haemophilus influenzae carriers: 7 (0.9%) carried serotype b, 14 (1.9%) serotype e, 6 (0.8%) serotype f, and 375 (51%) carried nontypable strains. The results show that, although the prevalence of Haemophilus influenzae carriers is similar to figures reported from other countries, the prevalence of Haemophillus influenzae serotype b carriers is lower and corresponds with the low incidence of invasive disease observed in the Catalan community.

Efficient production of transgenic citrus plants expressing the coat protein gene of citrus tristeza virus

 The coat protein gene of citrus tristeza virus (CTV) has been introduced into Mexican lime (Citrus aurantifolia Swing.) plants by using an improved Agrobacterium-mediated genetic transformation system. Internodal stem segments from greenhouse-grown seedlings were co-cultivated with A. tumefaciens strain EHA 105 carrying the binary plasmid pBI 121/CTV-CP in a medium rich in auxins that provided the explant cells with the proper treatment to shift them to a competent state for transformation. The transformation frequency was enhanced, and this allowed us to recover 42 transgenic plants from 1200 explants. Regenerated shoots were identified as transformants by performing β-glucuronidase (GUS) assays and subsequently by PCR amplifications of the CTV-CP transgene. Southern analyses revealed that at least one copy of the CTV-CP gene was integrated in all PCR positive plants. Interestingly, 70% of them had linked T-DNAs arranged at one locus. Copy number of the CTV-CP gene varied from one to six among the transgenic lines. Half of them showed truncated T-DNAs in which the left border was lost. Expression of the CTV-CP transgene was demonstrated in 38 out of 42 plants by western analysis and DASI-ELISA. No correlation was found between coat protein expression and transgene copy number or integration pattern.

Cell cycle regulated expression and phosphorylation of hpttg proto-oncogene product

We recently isolated a cDNA for hpttg, the human homolog of rat pituitary tumor transforming gene. Now we have analysed the expression of hpttg as a function of cell proliferation. hPTTG protein level is up-regulated in rapidly proliferating cells, is down-regulated in response to serum starvation or cell confluence, and is regulated in a cell cycle-dependent manner, peaking in mitosis. In addition, we show that hPTTG is phosphorylated during mitosis. Immunodepletion and in vitro phosphorylation experiments, together with the use of a specific inhibitor, indicate that Cdc2 is the kinase that phosphorylates hPTTG. These results suggest that hpttg is induced by, and may have a role in, regulatory pathways involved in the control of cell proliferation.