Association between self-replicating calcifying nanoparticles and aortic stenosis: a possible link to valve calcification.

AIMS: Among various hypotheses proposed for pathological tissue calcification, recent evidence supports the possibility that self-replicating calcifying nanoparticles (CNPs) can contribute to such calcification. These CNPs have been detected and isolated from calcified human tissues, including blood vessels and kidney stones, and are referred to as nanobacteria. We evaluated calcific aortic valves for the presence of CNP. METHODS AND RESULTS: Calcific aortic valves were obtained from 75 patients undergoing surgical valve replacement. The control group was formed by eight aortic valves corresponding to patients with heart transplants. In the microbiology laboratory, valves were screened for CNP using a 4-6 weeks specific culture method. The culture for CNP was positive in 48 of the 75 valves with aortic stenosis (64.0%) in comparison with zero of eight (0%) for the control group (P = 0.0005). The observation of cultures by way of scanning electron microscopy highlighted the resemblance in size and morphology of CNP. CONCLUSION: Self-replicating calcific nanometer-scale particles, similar to those described as CNP from other calcific human tissues, can be cultured and visualized from calcific human aortic valves. This finding raises the question as to whether CNP contribute to the pathogenesis of the disease or whether they are only innocent bystanders.

[Seroprevalence of viral hepatitis in a representative general population of an urban public health area in Castilla y León (Spain)]. / Seroprevalencia de las hepatitis virales en población general representativa de una zona básica de salud urbana en Castilla y León.

INTRODUCTION: Viral hepatitis is a major social, health and economic problem worldwide, requiring strict epidemiological control. METHODS: This study presents the viral hepatitis seroprevalence in a representative sample from an urban health care area in Valladolid (Spain). RESULTS: Antibody prevalence was as follows: anti-HAV 52%; anti-HBc, 8.2%; anti-HCV, 1.1%; anti-HEV, 0.8%; and anti-HGV 5.8%. Prevalence of anti-HAV, anti-HBc and anti-HGV increased significantly with age (P < 0.005 in all cases). In individuals younger than 20, prevalence of anti-HAV was 3.8%, anti-HBc < 0.28% and anti-HGV 1.3%. In the 20-39 year-old group, seroprevalence against HAV was associated with low educational levels (P = 0.009) and with birth in other provinces (P = 0.016). Anti-HBc seroprevalence was mainly associated with three factors: prior hospitalization before 1990 (P = 0.002; OR 3.32 [1.48-7.42]); compulsory military service before 1990 (P < 0.0001; OR 37.33 [3.68-378.03]); and acupuncture treatments (P = 0.018; OR 57.75 [26.17-127.42]). Seroprevalence against HGV was associated with hospitalizations before 1990 (P = 0.019; OR = 2.969 [1.154-7.639]). Seropositive status to HCV revealed a transfusion history (2 cases), hospitalization (1 case) or drug addiction (1 case). Only one case among those seropositive to HEV had a history of a prior trip to a HEV-endemic area. CONCLUSIONS: Our study shows that the seroprevalences of viral hepatitis in a representative sample of urban population of Castille and Leon are similar to the seroprevalences observed in the rest of Spain and other developed countries, lower than the ones observed in the studies performed in Spain in the last 20 years due to the measures of prophylaxis that were taken.

Utility of an immunocapture-agglutination test and an enzyme-linked immunosorbent assay test against cytosolic proteins from Brucella melitensis B115 in the diagnosis and follow-up of human acute brucellosis.

The utility of an immunocapture-agglutination (Brucellacapt, Vircell SL, Granada, Spain) test and an enzyme-linked immunosorbent assay IgG, IgA, and IgM (ELISA-IgG, ELISA-IgA, ELISA-IgM) against cytosolic proteins from Brucella melitensis B115 (R) was compared with ELISA-IgG, ELISA-IgA, and ELISA-IgM against smooth lipopolysaccharide (S-LPS) from B. melitensis 16M (S), serum agglutination test (SAT), and Coombs test in the diagnosis and follow-up for 10 months of 51 patients with acute brucellosis. The sensitivities of ELISA tests against cytosolic proteins varied from 49.0 % for ELISA-IgG to 64.7% for ELISA-IgM and were lower than the sensitivities showed by ELISA S-LPS (from 88.2% to 92.2%), SAT (88.2%), Coombs (96.1%), and Brucellacapt (98.0%) tests. Specificity was over 93% in all cases. The evolutionary behavior of the SAT, Coombs, and Brucellacapt tests was similar. There was a decrease of between 20% and 40% in antibody titer in the 10th month of evolution after treatment. The evolutional curves of IgG, IgA, and IgM against cytosolic protein increased slightly till the eighth month. The specific IgM and IgA antibodies against protein fractions began to show a drop from the eighth month on, showing levels slightly lower than the initial sera values by the end of the 10th month. In this month, titers of specific IgG against proteins fractions remained higher than the titers showed by the initial sera.

Seroepidemiologic study of Leishmania infantum infection in Castilla-Leon, Spain.

Leishmaniasis has increased in importance in recent years because infection with human immunodeficiency virus (HIV) has emerged as a risk factor for this disease. However, the actual prevalence of leishmaniasis in the general population of Spain is unknown. We present a study of the seroprevalence of infection with Leishmania infantum in the general population of Castilla-Leon, Spain. A random sample of individuals presenting to health care clinics (4,825 sera) and of HIV-infected patients in the autonomous community of Castilla-Leon was collected in 1996. The sero-prevalence of antibodies to L. infantum was determined by an indirect enzyme immunoassay and found to be 4.9% in the general population. There was a significant increase in seroprevalence with age (P = 0.001), from 3.96% in those 14-20 years old to 7.2% in those > 70 years old. There were no significant differences between women and men (5.0% versus 4.9%; P = 0.9534). Seroprevalence was significantly higher in people from rural areas than in those from cities (6.0% versus 3.4%; P = 0.001). Patients infected with HIV had a seroprevalence for L. infantum of 64.0%. No differences were observed between women and men, and prevalence did not increase with age.

Susceptibility of the Acinetobacter calcoaceticus-A. baumannii complex to imipenem, meropenem, sulbactam and colistin.

The Acinetobacter calcoaceticus-Acinetobacter baumannii complex includes some of the most clinically relevant species of the genus Acinetobacter due to their capacity to cause epidemic nosocomial outbreaks as well as their increasing resistance to antibiotics. Susceptibility of Acinetobacter strains varies greatly depending on origin, thus highlighting the importance of local analyses of susceptibility profiles. Two hundred twenty-one strains of the A. calcoaceticus-A. baumannii complex were identified using biochemical tests and were biotyped. Strain susceptibility to imipenem, meropenem, colistin and sulbactam was studied using agar dilution. Eight different biotypes were found, type 1 accounting for 69.2% of the strains. MIC(50) and MIC(90) to imipenem, meropenem, colistin and sulbactam were 4 and 8 mg/l, 16 and 32 mg/l, 0.5 and 1mg/l, and 8 and 16 mg/l, with susceptibility rates of 64.3, 22.6, 98.2 and 73.8%, respectively. Biotype 1 was the most resistant. A statistically significant difference was observed for the mean MIC of the four predominant biotypes to imipenem, meropenem and sulbactam but not to colistin.

[Seroprevalence of infection due to Echinococcus granulosus in the population of Castilla and León (Spain)]. / Seroprevalencia de infección por Echinococcus granulosus en la población de Castilla y León.

INTRODUCTION: Human hydatidosis is a prevalent zoonotic disease in the Castilla y León region of Spain. The aim of this study is to investigate the seroprevalence of Echinococcus granulosus infection in this region. METHODS: We studied 4824 serum samples from a random, representative population of healthy individuals from each province of Castilla y León, obtained over one year. An indirect enzyme-immunoassay developed in our laboratory was used to determine the presence of IgG antibodies against Echinococcus granulosus in these samples. RESULTS: IgG antibodies against Echinococcus granulosus were detected in 3.4% (164/4824) of samples studied, with a range of 1.26% to 7.10%, depending on the province. Antibody seroprevalence increased significantly with age, but there was no significant sex-related difference (3.66% men vs. 3.14% women). CONCLUSION: The seroprevalence of Echinococcus granulosus infection in Castilla y León is still high. These data contribute to hydatidosis surveillance within the control program for this disease.

Development of a dipstick dye immunoassay for diagnosing hydatidosis.

We have developed a kit to diagnose hydatidosis, based on the detection of specific antibodies. This disease, caused by larvae of the cestode Echinococcus granulosus, is a zoonosis commonly found throughout the world. The diagnostic kit discriminates between positive and negative cases in a way that is easily interpreted, i.e., positive cases form a colored band on an inert substrate. The results show test sensitivity to be some 94.87% and specificity 85.71%, which is comparable to those of the ELISA technique. The high sensitivity and specificity of this test affords the great advantage of speed in diagnosing this parasitosis. No other equipment or procedure is required.

Utility of a commercial immunoblot kit (BAG-Borrelia blot) in the diagnosis of the preliminary stages of Lyme disease.

The aim of this study was to evaluate the usefulness of a commercial immunoblot (IgG and IgM BAG-Borrelia blot) in the serologic diagnosis of the early stages of Lyme disease. A total of 42 sera from patients with Lyme disease (24 patients with localized early stage (LES) and 18 patients with disseminated early stage (DES)) and 129 sera from patients with non-Lyme diseases (specificity control sera) were studied. IgG anti-p41 from Borrelia burgdorferi s.l. was present in 95.2% of patients followed by anti-p41/I PBi (16.7%), anti-p100 (9.5%) and anti-OspA (9.5%). IgM anti-p41 was present in 66.7% of patients, p41/iPBi (54.8%) and OspC (33.3%). IgM against p100, OspA and OspC were more frequent in DES patients (16.7%, 27.8% and 44.4%) than in LES patients (0.0%, 4.2% and 25.0%). In 4.8% of the cases no IgG bands were present and in 26.2% no IgM bands were present. With the exception of isolated p41 bands (59.5%), no band pattern exceeded 17%. Using manufacturer's instructions, test sensitivity in diagnosis of the early stage of Lyme disease is 61.9%, specificity 98.4% and positive and negative predictive values 92.8% and 88.8% respectively. Applying the EUCALB 5, 6 or 7 rules sensitivity increased to 73.8% although specificity decreased to 89.9%. Of the 129 specific control sera, 41.8% presented IgG anti-p41 and 10.8% IgM anti-p41. Patients with non-Lyme diseases that presented more IgG and IgM bands were those patients with syphilis (88.2%), patients with anti-HIV antibodies (57.8%) and patients with anti-nuclear antibodies (ANA) (52.3%).

Serologic evidence of human infection by Francisella tularensis in the population of Castilla y León (Spain) prior to 1997.

Prior to an outbreak in Castilla y León in December 1997, tularaemia was practically non-existent in Spain. In this paper we studied the prevalence of antibodies against Francisella tularensis in a representative sample of the population (4825 people) from Castilla y León (Spain) in samples collected before this outbreak. Antibodies against F. tularensis were detected in nine (0.19%) of the 4825 sera, with antibody titres ranging from 1/20 to 1/160. Of these nine sera, one was positive in seroagglutination against Brucella. Seroagglutination against other bacteria (Yersinia enterocolitica O:9 and O:3 and Proteus OX19) was negative in all sera. Seroprevalence of antibodies in females was 0.20% and 0.17% in males; no statistically significant differences were found in prevalence in terms of sex, age or province.

[Prevalence of antibodies against Francisella tularensis in Castilla y León (Spain) before 1997]. / Prevalencia de anticuerpos frente a Francisella tularensis en la población de Castilla y León con anterioridad a 1997.

BACKGROUND AND OBJECTIVES: The aim of this paper was determine the prevalence of antibodies against Francisella tularensis in the representative sample of people from Castilla-León (Spain) before epidemic outbreak of end 1997. SUBJECTS AND METHOD: We obtain 4,825 sera (between april-1996 and april-1997) of people from Castilla-León. All sera were tested by a microagglutination technique to detect antibodies against Francisella tularensis. The positive sera were tested to determine cross-reaction with Brucella, Yersinia enterocolitica and Proteus in the tube agglutination tests. RESULTS: We detected antibodies against Francisella tularensis in 9 (0,19%) of the 4,825 sera. Only one serum from the 9 seropositive was positive in the tube agglutination against Brucella. None of the 9 sera were positive against the remaining bacterial antigen tested. CONCLUSIONS: In the people of Castilla-León before 1997 the prevalence of antibodies against Francisella tularensis was 0,19%.

[Genotypic resistance of human immunodeficiency virus in patients with virologic failure]. / Resistencias genotípicas del virus de la inmunodeficiencia humana en pacientes con fracaso virológico.

BACKGROUND: The aim of the present study is to asses the prevalence of resistances in a group of patients with virological failure establishing the relationship between the appearance of mutations and the given antiretroviral therapy along with other variables used in these patients follow-up. PATIENTS AND METHOD: Samples belonging to 88 patients were selected either with viral load levels above 30.000 copies/ml after reaching undetectable viral load levels, or with persistently detectable levels above 1.000 copies/ml. Resistances were tested by means of Line Probe Assay (LiPA). The history of patients' antiretroviral treatments was reviewed. RESULTS: Mutations were observed in 52,6% of cases for reverse transcriptase (RT) an in 81,8% for the protease genes, being T215Y and V82A the most frequently detected ones. Mutations coferring resistance to the given antiretrovirals appeared in 33 cases. No statistical significance was observed between the presence of mutations and the administered therapy. In the multivariate analysis we found for LiPA RT a greater risk of appearance of mutations according to patient motility (OR = 4,0). CONCLUSIONS: the prevalence of resistance mutations in patients with virologic failure is placed around 50% in both genes. A consensus in the definition of virologic failure in HIV infected patients is urged.

Comparative study of two methods for RNA extraction prior to detection of resistance to human immunodeficiency virus type 1 with the line probe assay.

We evaluated two methods from Roche and Promega for RNA extraction prior to the genotypic detection of human immunodeficiency virus type 1 resistance by line probe assay (LiPA). Fifty plasma RNA extracts were processed in parallel by LiPA. Results obtained by the Roche method were superior in the proportion of amplified samples, the percentage of mutated samples, and band intensity.