New policies for using anthelmintics in high risk groups

The 'Informal Consultation on the Use of Praziquantel during Pregnancy/Lactation, and Albendazole/Mebendazole in Children under 24 Months' was held 8-9 April 2002, in Geneva, Switzerland.     

Hepatitis C antibodies in groups at epidemic risk

Blood sera from patients with acute virus hepatitis, sexually transmitted diseases, psychiatric and oncological diseases and pulmonary tuberculosis were studied for the presence of antibodies to hepatitis C virus (anti-HCV) and HBsAg with the use of solid-phase enzyme immunoassay. Anti-HCV were detected, respectively, in 9.1% and 67.8% of patients with acute virus hepatitis, in 5.7% and 6.1% of patients with sexually transmitted diseases, in 7.5% and 9.2% of psychiatric patients, in 7.5% and 13% with pulmonary tuberculosis and malignant tumors.     

Using genetic variation and environmental risk factor data to identify individuals at high risk for age-related macular degeneration

A major goal of personalized medicine is to pre-symptomatically identify individuals at high risk for disease using knowledge of each individual's particular genetic profile and constellation of environmental risk factors. With the identification of several well-replicated risk factors for age-related macular degeneration (AMD), the leading cause of legal blindness in older adults, this previously unreachable goal is beginning to seem less elusive. However, recently developed algorithms have either been much less accurate than expected, given the strong effects of the identified risk factors, or have not been applied to independent datasets, leaving unknown how well they would perform in the population at large. We sought to increase accuracy by using novel modeling strategies, including multifactor dimensionality reduction (MDR) and grammatical evolution of neural networks (GENN), in addition to the traditional logistic regression approach. Furthermore, we rigorously designed and tested our models in three distinct datasets: a Vanderbilt-Miami (VM) clinic-based case-control dataset, a VM family dataset, and the population-based Age-related Maculopathy Ancillary (ARMA) Study cohort. Using a consensus approach to combine the results from logistic regression and GENN models, our algorithm was successful in differentiating between high- and low-risk groups (sensitivity 77.0%, specificity 74.1%). In the ARMA cohort, the positive and negative predictive values were 63.3% and 70.7%, respectively. We expect that future efforts to refine this algorithm by increasing the sample size available for model building, including novel susceptibility factors as they are discovered, and by calibrating the model for diverse populations will improve accuracy.     

The C system of cattle blood groups. 2. Partial genetic map of the system

20 cases of irregular inheritance of phenogroups in the C system of cattle blood groups were used to deduce a partial genetic map of this system, taking into consideration the 11 internationally recognized antigenic factors and the 4 additional factors recently described by Grosclaude et al. (1980). This partial map bears resemblance to that established by Bouw et al. (1974) in Dutch cattle.
The operational length of the DNA sequence coding for the C system was estimated to be 0.3 centimorgan, a value which is approximately half of that obtained for the B system by Grosclaude et al. (1979). It is concluded that the phenogroups of the C system, like those of the B system, are controlled by a cluster of loci.     

The C system of cattle blood groups. 2. Partial genetic map of the system

20 cases of irregular inheritance of phenogroups in the C system of cattle blood groups were used to deduce a partial genetic map of this system, taking into consideration the 11 internationally recognized antigenic factors and the 4 additional factors recently described by Grosclaude et al. (1980). This partial map bears resemblance to that established by Bouw et al. (1974) in Dutch cattle. The operational length of the DNA sequence coding for the C system was estimated to be 0.3 centimorgan, a value which is approximately half of that obtained for the B system by Grosclaude et al. (1979). It is concluded that the phenogroups of the C system. like those of the B system, are controlled by a cluster of loci.     

The genetic basis of spectral reflectance indices in drought-stressed wheat

Drought imposes a major constraint over the productivity of wheat, particularly in arid and semi-arid production zones. Here, the genetic basis of spectral reflectance indices was investigated in drought-stressed wheat by comparing, under two contrasting moisture regimes, the performance of an F₆ recombinant inbred line (RIL) population bred from a cross between the drought tolerant cultivar Pavon76 and the sensitive cultivar Yecora Rojo. The parents and RILs were genotyped with respect to both a set of microsatellite (SSR) loci and a number of known drought-responsive genes. In all, 28 quantitative trait loci (QTL) controlling dry weight per plant, water content of the above-ground biomass, leaf water potential, canopy temperature, and spectral reflectance indices traits were identified. The loci were distributed over 11 chromosomes, belonging to each of the three wheat sub-genomes. There were important location-flanking markers Barc109 and Barac4 on chromosome 5B relating to dry weight per plant accumulation under the limited irrigation regime. The same region-harbored QTL associated with leaf water potential, canopy temperature, and ratio index under the limited irrigation regime. Linkage between the known drought-responsive genes and aspects of the drought response was established. Some of QTL were of substantial enough effect for their linked markers to be likely usable for the marker-assisted breeding of drought tolerance in wheat.     

The genetic map of the B system of cattle blood groups as observed in French breeds

40 cases of irregular inheritance of phenogroups in the B system of cattle blood groups, that were presumed to have arisen from single crossing-over, have been used to establish a partial genetic map of this system. In addition, the relative positions in the map of several antigenic factors were inferred from relationships observed between particular phenogroups occurring in French breeds. The tentative map thus obtained shows an overall similarity to that established by Ruiterkamp et al. (1977) in Dutch Friesian cattle. This result, in addition to other arguments, supports the hypothesis that the genetic structure of the B system of cattle blood groups is basically the same in all taurine breeds. Evidence is given, for the first time, for the occurrence in the B system of genetic events other than single crossing-over (double crossing-over or gene conversion, and possibly deletion). The rate of recombination between the genetic determinants of the terminal factors of the system, Q and I', was calculated in the progeny of some Normande bulls heterozygous for these two determinants (447 gametes); a value of 1.34 centimorgan was obtained. However complementary data indicate that 0.7 centimorgan would be a better estimate.     

The genetic map of the B system of cattle blood groups as observed in French breeds

40 cases of irregular inheritance of phenogroups in the B system of cattle blood groups, that were presumed to have arisen from single crossing-over, have been used to establish a partial genetic map of this system. In addition, the relative positions in the map of several antigenic factors were inferred from relationships observed between particular phenogroups occurring in French breeds.
The tentative map thus obtained shows an overall similarity to that established by Ruiterkamp et al. (1977) in Dutch Friesian cattle. This result, in addition to other arguments, supports the hypothesis that the genetic structure of the B system of cattle blood groups is basically the same in all taurine breeds.
Evidence is given, for the first time, for the occurrence in the B system of genetic events other than single crossing-over (double crossing-over or gene conversion, and possibly deletion).
The rate of recombination between the genetic determinants of the terminal factors of the system, Q and I', was calculated in the progeny of some Normande bulls heterozygous for these two determinants (447 gametes); a value of 1.34 centimor-gan¹ was obtained. However complementary data indicate that 0.7 centimorgan would be a better estimate.     

Unmasking of histone amino groups in chromatin at high pH.

The reactivity of the amino groups of histones in chromatin towards acetic anhydride was determined as a function of pH. In the pH range 7-10 the vast majority of amino groups in all five histones are buried. However, at higher pH values some of the histone amino groups become exposed, and the higher the lysine:arginine ratio for the histone the greater was the degree of unmasking observed. At pH 11.8 histone I appears to be completely dissociated, histones IIB1 and IIb2 have approx. 55% of the amino groups unmasked, and histones III and IV have approx. 25% of the amino groups unmasked.     

The late stage of genetic code structuring took place at a high temperature

The correlation between the optimal growth temperature of organisms and a thermophily index based on the propensity of amino acids to enter more frequently into (hyper)thermophile proteins is used to conduct an analysis aiming to establish whether genetic code structuring took place at a low or a high temperature. If the number of codons attributed to the various amino acids in the genetic code constitutes an estimate of the mean amino acid composition of proteins produced when the genetic code was definitively structured, then the thermophily index can also be associated to the genetic code. This value and the sampling of the variable thermophily index of different alignments of protein sequences from mesophile, thermophile and hyperthermophile species make it possible to establish, with an extremely high statistical confidence, that the late stage of genetic code structuring took place in a hyperthermophile (or thermophile) 'organism'. Moreover the 95% confidence interval of the temperature at which the genetic code was fixed turned out to be 91+/-24 degrees C. These observations seem to support the hypothesis that the origin of life might have taken place at a high temperature.