Persistent environmental reservoirs on farms as risk factors for Campylobacter in commercial poultry.

Campylobacter is the most common known source of human bacterial enteritis in the developed world and poultry is considered the main source. Broilers often become colonized with Campylobacter during rearing, and then contaminate the farm environment. The objective of this study was to identify Campylobacter-positive environmental reservoirs on farms, as these pose a risk to broiler flocks becoming colonized with Campylobacter. We considered the temporal aspects of exposure and colonization. A longitudinal study monitored six conventional rearing farms over 2 years. The broiler flocks, catchers' equipment, vehicles, shed surrounds, shed entrance, other equipment, farm entrance, other animals, puddles, dead birds, mains water and drinkers were systematically sampled 2-4 times per flock. A multivariable generalized estimating equation model was used to assess associations between contaminated environmental sites and colonized broiler flocks. The associations were adjusted for confounders and other known risk factors. To further assess temporality of contamination, the sequence of contamination of the different environmental sites and the flocks was established. Contaminated shed entrances and anterooms, contaminated drinkers and shedding of Campylobacter by other animals such as cattle, dogs, wildlife and rodents were significantly associated with positive flocks. The reservoir of 'other animals' was also the reservoir most commonly positive before the flock became colonized. The other sites usually became contaminated after the flock was colonized.

[Descriptive study of diabetic foot at the Marc Sankale Diabetes Center. Report of 105 cases]. / Etude descriptive du pied diabetique au centre du diabete marc sankale. A propos de 105 cas.

INTRODUCTION: Diabetic foot is a major complication of diabetes due to its frequency and its high risk of evolution to amputation. We report 105 cases recruited at the diabetes centre Marc Sankale. METHOD: It's a prospective study including all diabetic patients who attended the diabetes centre for any foot lesion during a one year period. Besides clinical examination data, results of glycaemia, foot X-ray Doppler and bacteriological analysis of the pus were collected. RESULTS: foot lesion represented 2.8% of diabetologist causes of consultation. Mean age of occurrence was 55 +/- 14 years in 63% women and 37% men. Diabetes was type 2 in 90% cases, poorly controlled in 63.92 % cases. Foot lesion was dominated by infection (97%), isolated or associated to peripheral vascular disease (32.4%) or neuropathy (13.3%). 67 patients had medical treatment and healed their wounds in 3 months in 76% cases. 38 other cases needed surgery : major amputation (15%), minor amputation (13%) debridment (9%) and revascularization (1%). CONCLUSION: Diabetic foot is a frequent reason for consultation at the National diabetes centre. Despite all the improvements made after the implementation of the patient's educational program, treatment starts late because of economical and cultural reasons that increase morbidity.

Chemical composition of two mineralogically contrasting Arctic bivalves' shells and their relationships to environmental variables.

The main goal of this study was to determine the concentrations of trace elements in the mineralogically contrasting shells of two Arctic bivalves: Chlamys islandica and Ciliatocardium ciliatum. Aragonite shells seem to be more susceptible to the binding of metal ions, which is most likely a result of their crystal lattice structure. We suggest that less biologically controlled aragonite mineralization tends to incorporate more metal impurities into the crystal lattice in waters with a lower pH, where metal ions are more available. Higher concentrations of impurities may further increase the lattice distortion causing lower crystal lattice stability and higher susceptibility to dissolution. Calcitic shells seem to be less prone to bind metal ions than aragonite shells most likely because under strict biological control, the uptake of ions from ambient seawater is more selective; thus, the final crystal lattice is less contaminated by other metals and is more resistant to dissolution.

Mutational analysis of human uroporphyrinogen decarboxylase.

Uroporphyrinogen decarboxylase (URO-D), a heme biosynthetic enzyme, catalyzes the multi-step decarboxylation reaction converting uroporphyrinogen I or III to coproporphyrinogen I or III. The URO-D protein has been purified from several sources and its gene has been cloned from many organisms. In spite of this, little is known about the active site(s) of the enzyme. Inhibitor studies suggest that cysteine and histidine residues are important for enzyme activity. We employed the Kunkel method of site-directed mutagenesis to convert each of the six cysteines in human URO-D to serine and each of the three conserved histidines to asparagine. Recombinant mutant URO-D's were expressed in Escherichia coli, partially purified, and their kinetic properties compared to recombinant wild-type URO-D. All cysteine mutants retained approx. 40% wild-type enzyme activity, indicating that no single cysteine is absolutely critical for the integrity of the catalytic site. The three histidine mutants also retained significant enzyme activity and one, (H339N), displayed unique properties. The H339N mutation resulted in an enzyme with high residual activity but decarboxylation of intermediate reaction products of the I isomer series was markedly abnormal. The histidine at residue 339 is likely important in imparting isomer specificity.

Influenza A virus NP protein expressed in insect cells by a recombinant baculovirus is associated with a protein kinase activity and possesses single-stranded RNA binding activity.

Influenza A virus NP protein, the phosphoprotein associated with viral RNA in ribonucleoprotein (RNP) complexes, has been expressed at high levels (approximately 100 mg/liter cells) in insect (Sf9) cells by a baculovirus recombinant, and was localized almost entirely in the nuclei of these cells. NP was purified by immuno-affinity chromatography, and purified NP was shown to autophosphorylate and to phosphorylate casein in a cAMP-independent reaction. Furthermore, purified NP was able to bind to ssRNA as demonstrated by a mobility shift of ssRNA in non-denaturing gels. The binding of NP to ssRNA caused a diminution of its kinase activity in proportion to binding.

Nonsymbiotic haemoglobins in plants.

General aspects regarding the presence of nonsymbiotic haemoglobin in plants are presented with the emphasis on those related to its function. As it becomes apparent that the nonsymbiotic haemoglobins are widespread across the plant kingdom and that they represent a more primitive and evolutionary older form of the plant globin genes, the question of their function becomes more attractive. While the physiological functions of the symbiotic haemoglobins in plants are well understood, almost nothing is known about their nonsymbiotic predecessors. Therefore, the known and hypothetical functions of haemoglobins in various systems are described along with information concerning properties and the regulation of expression of the nonsymbiotic haemoglobins. Interestingly, a number of nonsymbiotic haemoglobins have been shown to be hypoxia-inducible. The spatial and temporal pattern of this induction in barley may suggest that it is an integral part of the plants response to limiting oxygen stress.

Effect of additives on refolding of a denatured protein.

Denatured lysozyme was refolded by a dilution method. The refolding yield depended greatly on the lysozyme concentration in the refolding mixture. When the concentration of denatured lysozyme was 0.02 g/L, the refolding yield was as high as 60%. However, when the concentration of denatured lysozyme was 0.2 g/L, the refolding yield was as low as 10% due to the formation of aggregates. To prevent the formation of aggregates and to increase the refolding yield at a low cost, inexpensive additives were screened. The addition of acetone, acetoamide, or urea derivatives was very effective for improving the refolding yield. To clarify why the addition of acetoamide in the refolding mixture improved the refolding yield at the high lysozyme concentration, the time courses of the concentration and the average diameter of the aggregates in the refolding mixture were monitored by the dynamic light scattering method. The experimental results showed that acetoamide played a role in preventing the formation and growth of aggregates and secondary aggregation between the lysozyme aggregates.

Philosophical assumptions in Freud, Jung and Bion: questions of causality.

The historical development of concepts of causality in philosophy is described. Since the Enlightenment and the growth of science, exponents of the two most important concepts, determinism and teleology, have been in conflict. At the inception of psychoanalysis at the end of the nineteenth century this conflict was particularly intense. It was the cause of the first major schism in psychoanalysis between Jung and Freud. Psychoanalytic theorists have continued to disagree over this issue. Post-modernist philosophy has abolished all metaphysics and therefore called into question concepts of psychic causality. Parallel to, but uninfluenced by this development, Bion has developed a psychoanalytic conceptualization which may be seen as transcending causality. The clinical and theoretical implications of these developments are described.

Yttrium-90 distribution following radiosynoviorthesis of the knee joint in rheumatoid arthritis patients: a SPECT/CT study.

OBJECTIVE: To examine yttrium-90 distribution 1 and 72 h following its injection into a knee joint in patients with rheumatoid arthritis (RA). METHODS: In 14 RA patients we injected yttrium-90 into the affected knee joint using lateral approach. To assess the radioisotope distribution in the joint, the superimposed sequential SPECT and CT imaging was performed 1 and 72 h after the injection. We analyzed the percentage of radioisotope distribution in three predefined compartments of the knee joint (lower, upper medial, upper lateral). RESULTS: After 1 and 72 h, the mean percentage distributions were, respectively, 7.14 and 23.07% in lower; 21.42 and 15.38% in upper medial, and 71.42 and 61.53% in upper lateral compartment. The percentage of isotope deposition did not change significantly with time in any of the compartments (all p > 0.26). The deposition of isotope, both at 1 and 72 h, was significantly greater in upper lateral compartment, where the injection was performed, than in all other compartments (all p < 0.05). CONCLUSIONS: Using the SPECT/CT hybrid method, we proved that the majority of isotope is located at the compartment adjacent to the injection. Two injections targeting different compartments might improve the clinical efficacy of the procedure.

Maternal allergy as a potential source of variability of exhaled nitric oxide in children non-sensitized to common domestic allergens.

The goal of the study is to evaluate the importance of maternal atopy as a potential biological source of variability of exhaled FeNO values in healthy children who were non-asthmatic and non-sensitized to common domestic allergens. The study sample consisted of 61 seven-year old children. Fractional exhaled nitric oxide (FeNO) has been measured by NObreath (Bedfont portable device). Children with reported maternal atopy had significantly higher mean FeNO values (geometric mean =10.7 ppb; 95%CI: 6.7-17.1 ppb) than those who denied it (geometric mean =5.2 ppb 95%CI: 3.9-6.9 ppb) (p=0.010). Neither the correlation between FeNO values and gender, respiratory and eczema symptoms, nor ETS exposure in the prenatal and postnatal period or body mass of children were significant. We also found no significant association of FeNO values with the amount of common domestic allergens measured in the households. The results of the ROC analysis suggested 11 ppb as the cut-off point for FeNO to distinguish groups of healthy children with and without maternal atopy. In conclusion, our study provided some evidence suggesting that maternal atopy may affect FeNO level in children independently of asthma and sensitization status to common domestic allergens. The data should be considered in the interpretation of FeNO levels in clinical practice and setting up FeNO screening criteria for identification of eosinophilic airway inflammation.

Impact of excessive gestational weight gain in non-smoking mothers on body fatness in infancy and early childhood. Prospective prebirth cohort study in Cracow.

Gestational weight gain (GWG) is important for health policy as it may be associated with overweight epidemics in childhood and adolescence. The purpose of the study was to perform the risk assessment of joint effects of the excessive GWG and the pregravid maternal BMI on overweight in infancy and childhood. The observations were collected in the ongoing prospective birth cohort study of 482 non-smoking mothers and their newborns in Cracow inner city area. At 5 years of age the subsample of 312 infants were reexamined in order to assess their nutritional status. Body fatness was assessed by means of the weight/length ratio (WLR) in neonates and weight/height ratio (WHR) in 5-year-olds since they showed the strongest correlation with subcutaneous fat mass of young children. In the statistical analysis the binary regression models were applied to identify predictors of overweight. The excessive GWG (>18 kg) increased more than twofold the adjusted relative risk (RR) of neonatal fatness (R=2.7; 95% CI 2.0-3.7) and was also a significant independent risk factor for postnatal body fatness at 5 years of age (RR=2.0; 95% CI: 1.3-3.3). The results confirmed earlier findings that pregravid overweight increased not only the relative risk of neonatal fatness (RR=2.9; 95% CI: 2.2-3.9) but also overweight in early childhood (RR=2.7; 95% CI: 1.7-4.4). The conclusion is that excessive GWG may be a risk factor for overweight in early childhood and should be a focus of public health policy.

The impact of handpump corrosion on water quality in rural areas of West African sub-region.

Water, even in its natural environment, contains some level of impurities. Water is nearly a universal solvent. It contains dissolved solids and gases, and hosts a number of micro-organisms. The exploitation of groundwater by means of boreholes for supplying small user groups and rural communities with water has been widely applied in certain parts of the world for several decades. In recent years this practice has spread all over the globe, and hundred of thousands of boreholes have been drilled to tap low-yield aquifers. It is evident that such boreholes require pumps for lifting the water. In developing countries these are usually handpumps, but solar as well as other systems with submersible pumps are also used, depending upon the energy sources available and the financial means of the beneficiaries. This article gives a general overview of groundwater quality with regard to its physico-chemical composition. The results presented originate from the experience gained from handpump equipped boreholes within the UNICEF through German Centre for Technical Education Transfer executed inter-regional UNDP-Handpumps Project in West African Regions. Particular attention is paid to presenting corrosion on the water quality of wells in terms of iron concentration and other parameters. Furthermore, the corrosion attack on galvanised iron, the effect of biofilms on the corrosion rate, and the difference between internal and external corrosion of rising mains are shown.

Altering hemoglobin levels changes energy status in maize cells under hypoxia.

Nonsymbiotic hemoglobins are broadly present across the plant kingdom; however, the function of these proteins is unknown. Cultured maize cells have been transformed to constitutively express a barley hemoglobin gene in either the sense (HB+) or antisense (HB-) orientation. Hemoglobin protein in the transformed cell lines correspondingly was higher or lower than in wild-type cells under normal atmospheric conditions. Limiting oxygen availability, by placing the cells in a nitrogen atmosphere for 12 hr, had little effect on the energy status of cells constitutively expressing hemoglobin, but had a pronounced effect on both wild-type and HB- cells, where ATP levels declined by 27% and 61%, respectively. Total adenylates in these cells were approximately 35% lower than in HB+ cells. Energy charge was relatively unaffected by the treatment in HB+ and wild-type cells, but was reduced from 0.91 to 0.73 in HB- cells, suggesting that the latter were incapable of maintaining their energy status under the low oxygen regime. Treatment of the cells grown in an air atmosphere with antimycin A gave essentially the same results. It is suggested that nonsymbiotic hemoglobins act in plants to maintain the energy status of cells in low oxygen environments and that they accomplish this effect by promoting glycolytic flux through NADH oxidation, resulting in increased substrate-level phosphorylation. Hypoxic acclimation of plants is an example of this effect in nature. Nonsymbiotic hemoglobins are likely ancestors of an early form of hemoglobin that sequestered oxygen in low oxygen environments, providing a source of oxygen to oxidize NADH to provide ATP for cell growth and development.