Anaesthesia and the acute phase protein response in children undergoing circumcision

Concentrations of acute phase proteins (CRP: C-reactive protein, albumin) change during surgery. We investigated the acute phase response to circumcision and the effects of anaesthesia on this response. The children were divided into four groups; group 1 (intratracheal general anaesthesia, n=40), group 2 (general anaesthesia with mask, n=20), group 3 (ketamine, n=20), group 4 (local anaesthesia, n=35). Blood samples were obtained, 24 hours before circumcision, after premedication, and 24 hours after circumcision. CRP and albumin before circumcision were comparable for all groups. There was no increase in CRP, and albumin remained steady throughout the study. No difference was observed among the groups, and related to anaesthesia. No responsiveness may be explained with the size of injured tissue or anatomical and histological type of preputium.     

Triticum durum metallothionein. Isolation of the gene and structural characterization of the protein using solution scattering and molecular modeling

A novel gene sequence, with two exons and one intron, encoding a metallothionein (MT) has been identified in durum wheat Triticum durum cv. Balcali85 genomic DNA. Multiple alignment analyses on the cDNA and the translated protein sequences showed that T. durum MT (dMT) can be classified as a type 1 MT. dMT has three Cys-X-Cys motifs in each of the N- and C-terminal domains and a 42-residue-long hinge region devoid of cysteines. dMT was overexpressed in Escherichia coli as a fusion protein (GSTdMT), and bacteria expressing the fusion protein showed increased tolerance to cadmium in the growth medium compared with controls. Purified GSTdMT was characterized by SDS- and native-PAGE, size exclusion chromatography, and matrix-assisted laser desorption ionization time-of-flight mass spectrometry. It was shown that the recombinant protein binds 4 +/- 1 mol of cadmium/mol of protein and has a high tendency to form stable oligomeric structures. The structure of GSTdMT and dMT was investigated by synchrotron x-ray solution scattering and computational methods. X-ray scattering measurements indicated a strong tendency for GSTdMT to form dimers and trimers in solution and yielded structural models that were compatible with a stable dimeric form in which dMT had an extended conformation. Results of homology modeling and ab initio solution scattering approaches produced an elongated dMT structure with a long central hinge region. The predicted model and those obtained from x-ray scattering are in agreement and suggest that dMT may be involved in functions other than metal detoxification.     

The induction of chromosomal aberrations by tetra antibiotic in bone marrow cells of rats in vivo

The aim of this study was to investigate the in vivo effects of Tetra (Tetralet) antibiotic on the chromosomal aberrations (CA) in bone marrow cells of rats (Rattus norvegicus var. albinos). Tetra antibiotic significantly increased the percentage of abnormal cells and the chromosomal aberrations per cells (CA/cell) in bone marrow cells of rats at concentrations of 100 and 200 mg/kg body weight for 12 and 24 hours treatment periods for each. In addition, the percentage of abnormal cells and the CA/cell increased dose-dependently for 12 hours treatment period; In contrast, mitotic index (MI) was decreased when compared with negative control and solvent controls for 12 hours treatment period. However, MI increased depend on Tetra antibiotic dose for 24 hour treatment period.     

Climate change and future temperature-related mortality in 15 Canadian cities

The environmental changes caused by climate change represent a significant challenge to human societies. One part of this challenge will be greater heat-related mortality. Populations in the northern hemisphere will experience temperature increases exceeding the global average, but whether this will increase or decrease total temperature-related mortality burdens is debated. Here, we use distributed lag modeling to characterize temperature-mortality relationships in 15 Canadian cities. Further, we examine historical trends in temperature variation across Canada. We then develop city-specific general linear models to estimate change in high- and low-temperature-related mortality using dynamically downscaled climate projections for four future periods centred on 2040, 2060 and 2080. We find that the minimum mortality temperature is frequently located at approximately the 75th percentile of the city’s temperature distribution, and that Canadians currently experience greater and longer lasting risk from cold-related than heat-related mortality. Additionally, we find no evidence that temperature variation is increasing in Canada. However, the projected increased temperatures are sufficient to change the relative levels of heat- and cold-related mortality in some cities. While most temperature-related mortality will continue to be cold-related, our models predict that higher temperatures will increase the burden of annual temperature-related mortality in Hamilton, London, Montreal and Regina, but result in slight to moderate decreases in the burden of mortality in the other 11 cities investigated.     

Phytosiderophore release in Aegilops tauschii and Triticum species under zinc and iron deficiencies.

Using three diploid (Triticum monococcum, AA), three tetraploid (Triticum turgidum, BBAA), two hexaploid (Triticum aestivum and Triticum compactum, BBAADD) wheats and two Aegilops tauschii (DD) genotypes, experiments were carried out under controlled environmental conditions in nutrient solution (i) to study the relationships between the rates of phytosiderophore (PS) release from the roots and the tolerance of diploid, tetraploid, and hexaploid wheats and AE: tauschii to zinc (Zn) and iron (Fe) deficiencies, and (ii) to assess the role of different genomes in PS release from roots under different regimes of Zn and Fe supply. Phytosiderophores released from roots were determined both by measurement of Cu mobilized from a Cu-loaded resin and identification by using HPLC analysis. Compared to tetraploid wheats, diploid and hexaploid wheats were less affected by Zn deficiency as judged from the severity of leaf symptoms. Aegilops tauschii showed very slight Zn deficiency symptoms possibly due to its slower growth rate. Under Fe-deficient conditions, all wheat genotypes used were similarly chlorotic; however, development of chlorosis was first observed in tetraploid wheats. Correlation between PS release rate determined by Cu-mobilization test and HPLC analysis was highly significant. According to HPLC analysis, all genotypes of Triticum and AE: tauschii species released only one PS, 2'-deoxymugineic acid, both under Fe and Zn deficiency. Under Zn deficiency, rates of PS release in tetraploid wheats averaged 1 micromol x (30 plants)(-1) x (3 h)(-1), while in hexaploid wheats rate of PS release was around 14 micromol x (30 plants)(-1) x (3 h)(-1). Diploid wheats and AE: tauschii accessions behaved similarly in their capacity to release PS and intermediate between tetraploid and hexaploid wheats regarding the PS release capacity. All Triticum and Aegilops species released more PS under Fe than Zn deficiency, particularly when the rate of PS release was expressed per unit dry weight of roots. On average, the rates of PS release under Fe deficiency were 3.0, 5.7, 8.4, and 16 micromol x (30 plants)(-1) x (3 h)(-1) for AE: tauschii, diploid, tetraploid and hexaploid wheats, respectively. The results of the present study show that the PS release mechanism in wheat is expressed effectively when three genomes, A, B and D, come together, indicating complementary action of the corresponding genes from A, B and D genomes to activate biosynthesis and release of PS.     

Uptake and transport of foliar applied zinc (65Zn) in bread and durum wheat cultivars differing in zinc efficiency

Using two bread wheat (Triticum aestivum) and two durum wheat (Triticum durum) cultivars differing in zinc (Zn) efficiency, uptake and translocation of foliar-applied ⁶⁵Zn were studied to characterize the role of Zn nutritional status of plants on the extent of phloem mobility of Zn and to determine the relationship between phloem mobility of Zn and Zn efficiency of the used wheat cultivars. Irrespective of leaf age and Zn nutritional status of plants, all cultivars showed similar Zn uptake rates with application of ⁶⁵ZnSO₄ to leaf strips in a short-term experiment. Also with supply of ⁶⁵ZnSO₄ by immersing the tip (3 cm) of the oldest leaf of intact plants, no differences in Zn uptake were observed among and within both wheat species. Further, Zn nutritional status did not affect total uptake of foliar applied Zn. However, Zn-deficient plants translocated more ⁶⁵Zn from the treated leaf to the roots and remainder parts of shoots. In Zn-deficient plants about 40% of the total absorbed ⁶⁵Zn was translocated from the treated leaf to the roots and remainder parts of shoots within 8 days while in Zn-sufficient plants the proportion of the translocated ⁶⁵Zn of the total absorbed ⁶⁵Zn was about 25%. Although differences in Zn efficiency existed between the cultivars did not affect the translocation and distribution of ⁶⁵Zn between roots and shoots. Bread wheats compared to durum wheats, tended to accumulate more ⁶⁵Zn in shoots and less ⁶⁵Zn in roots, particularly under Zn-deficient conditions. The results indicate that differences in expression of Zn efficiency between and within durum and bread wheats are not related to translocation or distribution of foliar-applied ⁶⁵Zn within plants. Differential compartementation of Zn at the cellular levels is discussed as a possible factor determining genotypic variation in Zn efficiency within wheat.     

Sustainability indices for exploited populations

Evaluating the sustainability of hunting is key to the conservation of species exploited for bushmeat. Researchers are often hampered by a lack of basic biological data, the usual response to which is to develop sustainability indices based on highly simplified population models. However, the standard indices in the bushmeat literature do not perform well under realistic conditions of uncertainty, bias in parameter estimation, and habitat loss. Another possible approach to estimating the sustainability of hunting under uncertainty is to use Bayesian statistics, but this is mathematically demanding. Red listing of threatened species has to be carried out in extremely data-poor situations: uncertainty has been incorporated into this process in a relatively simple and intuitive way using fuzzy numbers. The current methods for estimating sustainability of bushmeat hunting also do not incorporate spatial heterogeneity. No-take areas are one management tool that can address uncertainty in a spatially explicit way.     

Uptake of zinc by rye,bread wheat and durum wheat cultivars differing in zinc efficiency

Effect of zinc (Zn) nutritional status on uptake of inorganic ⁶⁵Zn was studied in rye (Secale cereale, cv. Aslim), three bread wheat (Triticum aestivum, cvs. Dagdas, Bezostaja, BDME-10) and durum wheat (Triticum durum, cv. Kunduru-1149) cultivars grown for 13 days in nutrient solution under controlled environmental conditions. The cultivars were selected based on their response to Zn deficiency and to Zn fertilization in calcareous soils under field conditions. When grown in Zn-deficient calcareous soil in the field, the rye cultivar had the highest, and the durum wheat the lowest Zn efficiency. Among the bread wheats, BDME-10 showed higher susceptibility to Zn deficiency and Bezostaja and Dagdas were less affected by Zn deficiency. Similarly to field conditions, in nutrient solution visual Zn deficiency symptoms (i.e. necrotic lesions on leaf blade) appeared to be more severe in Kunduru-1149 and BDME-10 and less severe in rye cultivar Aslim. Under Zn deficiency, shoot concentrations of Zn were similar between all cultivars. Cultivars with adequate Zn supply did not differ in uptake and root-to-shoot translocation rate of ⁶⁵Zn, but under Zn deficiency there were distinct differences; rye showed the highest rate of Zn uptake and the durum wheat the lowest. In the case of bread wheat cultivars, ⁶⁵Zn uptake rate was about the same and not related to their differential Zn efficiency. Under Zn deficiency, rye had the highest rate of root-to-shoot translocation of ⁶⁵Zn, while all bread and durum wheat cultivars were similar in their capacity to translocate ⁶⁵Zn from roots to shoots. When Zn²⁺ activity in uptake solution ranged between 117 p M and 34550 pM, Zn-efficient and Zn-inefficient bread wheat genotypes were again similar in uptake and root-to-shoot translocation rate of ⁶⁵Zn. The results indicate that high Zn efficiency of rye can be attributed to its greater Zn uptake capacity from soils. The inability of the durum wheat cultivar Kunduru-1149 to have a high Zn uptake capacity seems to be an important reason for its Zn inefficiency. Differential Zn efficiency between the bread wheat cultivars used in this study is not related to their capacity to take up inorganic Zn. This revised version was published online in June 2006 with corrections to the Cover Date.