Proximity effects in chromosome aberration induction by low-LET ionizing radiation

Although chromosome aberrations are known to derive from distance-dependent mis-rejoining of chromosome fragments, evaluating whether a certain model describes such “proximity effects” better than another one is complicated by the fact that different approaches have often been tested under different conditions. Herein, a biophysical model (“BIANCA”, i.e. BIophysical ANalysis of Cell death and chromosome Aberrations) was upgraded, implementing explicit chromosome-arm domains and two new models for the dependence of the rejoining probability on the fragment initial distance, r. Such probability was described either by an exponential function like exp(−r/r₀), or by a Gaussian function like exp(−r²/2σ²), where r₀ and σ were adjustable parameters. The second, and last, parameters was the yield of “Cluster Lesions” (CL), where “Cluster Lesion” defines a critical DNA damage producing two independent chromosome fragments. The model was applied to low-LET-irradiated lymphocytes (doses: 1–4 Gy) and fibroblasts (1–6.1 Gy). Good agreement with experimental yields of dicentrics and centric rings, and thus their ratio (“F-ratio”), was found by both the exponential model (with r₀ = 0.8 μm for lymphocytes and 0.7 μm for fibroblasts) and the Gaussian model (with σ = 1.1 μm for lymphocytes and 1.3 μm for fibroblasts). While the former also allowed reproducing dose-responses for excess acentric fragments, the latter substantially underestimated the experimental curves. Both models provided G-ratios (ratio of acentric to centric rings) higher than those expected from randomness, although the values calculated by the Gaussian model were lower than those calculated by the exponential one. For lymphocytes the calculated G-ratios were in good agreement with the experimental ones, whereas for fibroblasts both models substantially underestimated the experimental results, which deserves further investigation. This work suggested that, although both models performed better than a step model (which previously allowed reproducing the F-ratio but underestimated the G-ratio), an exponential function describes proximity effects better than a Gaussian one.     

Self-similar land cover heterogeneity of temperate and tropical landscapes

Landscapes are complex objects often showing self-similar properties. For example, some power law exponents and fractal dimensions have been extensively used as global metrics for describing spatial arrangements of landscape land covers. This paper presents some newly found invariance properties for rural landscapes, with the hope to prepare further theory capable to link these properties mechanistically with generating processes. For this purpose, I propose a new surface-pattern analysis computing heterogeneity metrics into moving windows in a specific way. This generic method provides Multiscale Heterogeneity Maps (MHMs) and Heterogeneity Profiles (HPs) of almost any kind of landscape. Six landscapes, covering a wide range of observed mosaics have been analyzed by this way: four of them exhibit strong self-similar evenness (diversity) heterogeneity over two orders of magnitude with an apparent universality of the power law exponents (γ = ?0.19 ± 0.02). Such landscape self-organization is interpreted in terms of spatial arrangements of numerous land covers and fine scale patchy mosaics. This study suggests that most of terrestrial landscapes could exhibit power law behaviors in terms of evenness heterogeneity and could be the result of a hidden optimization of ecological and/or socio-economic processes.     

Stress as adaptation? A test of the adaptive boost hypothesis among Batswana men

Many studies have found elevated cortisol linked to negative events (“stress”) and subsequent negative outcomes, such as reduced immunity and stunted growth, leading to the conclusion that high cortisol is “bad.” However, a growing number of studies have found more advantaged groups showing relatively elevated cortisol. For example, higher morning cortisol followed by a steeper diurnal decline among Caucasians compared to ethnic minorities has been interpreted as a context-specific “adaptive boost” to meet daily demands. We tested the adaptive boost hypothesis using data on socioeconomic status, depressive affect and salivary cortisol among adult men (n = 32) in Botswana. Three findings emerged: (i) depressive affect was associated with lower morning cortisol (r = ? 0.43, p = 0.014); (ii) depressive affect was associated with a diurnal increase in cortisol when comparing morning and evening samples (r = 0.49, p = 0.004); and (iii) depressive affect was associated with lower income (r = ? 0.55, p = 0.001). Findings are consistent with the adaptive boost hypothesis and add to a growing body of evidence that elevated cortisol is not universally bad. Hypothalamic–pituitary adrenal axis (HPAA) activity, such as cortisol, may be adaptive depending on a person's contextual circumstances. Based on our findings and those of previous studies, we develop a “person-in-context” model of the threat appraisal process. Integrated with life history theory, our model facilitates testable hypotheses about intra- and inter-individual variability in HPAA and adaptive consequences.     

Results of the implementation of the System for the Integrated Assessment of Protected Areas (SIAPA) to the protected areas of the Autonomous Region of Madrid (Spain)

The long-term conservation of biodiversity and related ecosystems goods and services of the Autonomous Region of Madrid is jeopardized by the intensive resource-consuming development model followed by the region in the past few decades. This paper presents the aggregated results of the first integrated assessment of the protected areas of the Autonomous Region of Madrid (Spain) with the System for the Integrated Assessment of Protected Areas (SIAPA). Detailed results are also provided for individual protected areas as supplementary data. The assessment was done during 2009–2010, on ten protected areas differing in their sizes (from 2.5 to 52,796 ha), protection categories (seven categories) and types of ecosystems present. Comparison of results from both assessment models of the SIAPA (the Complete Model and the Simplified Model) is also presented. The results from the Complete Model show that eight out of the ten protected areas of the Autonomous Region of Madrid are currently ineffective. The poorest partial indexes overall were: “State of Conservation” and “Social and Economic Context”. The only indexes significantly correlated with the effectiveness of a protected area were: the “State of Conservation” (r = 0.851**) and the “Social Perception and Valuation” (r = 0.786**). Although not as relevant as was thought, “Management” and the other non-significant factors are likely to influence the effectiveness of protected areas as well. The results for the Simplified Model are slightly better than those for the Complete Model, although this is probably a specific result of this assessment. The two models of the SIAPA were very significantly correlated, although their aggregated results should not be compared directly.     

The effect of inspiratory and expiratory loads on abdominal muscle activity during breathing in subjects “at risk” for the development of chronic obstructive pulmonary disease and healthy

The abdominal muscle activity has been shown to be variable in subjects with chronic obstructive pulmonary disease (COPD) when respiratory demand increases and their recruitment pattern may change the mechanics, as well as the work and cost of breathing. The scientific evidence in subjects “at risk” for the development of COPD may be important to understand the natural history of this disease. This study aims to evaluate the effect of inspiratory and expiratory loads on the abdominal muscle activity during breathing in subjects “at risk” for the development of COPD and healthy. Thirty-one volunteers, divided in “At Risk” for COPD (n = 17; 47.71 ± 5.11 years) and Healthy (n = 14; 48.21 ± 6.87 years) groups, breathed at the same rhythm without load and with 10% of the maximal inspiratory or expiratory pressures, in standing. Surface electromyography was performed to assess the activation intensity of rectus abdominis (RA), external oblique and transversus abdominis/internal oblique (TrA/IO) muscles, during inspiration and expiration. During inspiration, in “At Risk” for COPD group, RA muscle activation was higher with loaded expiration (p = 0.016); however, in Healthy group it was observed a higher activation of external oblique and TrA/IO muscles (p < 0.050). During expiration, while in “At Risk” for COPD group, RA muscle activation was higher with loaded inspiration (p = 0.009), in Healthy group TrA/IO muscle showed a higher activation (p = 0.025). Subjects “at risk” for the development of COPD seemed to have a specific recruitment of the superficial layer of ventrolateral abdominal wall for the mechanics of breathing.     

Rapid torque development in older female fallers and nonfallers: A comparison across lower-extremity muscles

The objective of this study was to compare reaction time, joint torque, rate of torque development, and magnitude of neuromuscular activation of lower-extremity muscles in elderly female fallers and nonfallers. Participants included 11, elderly, female fallers (71.3 ± 5.4 years) and twelve nonfallers (71.3 ± 6.2 years) who completed a fall risk questionnaire. Then, maximal, voluntary, isometric contractions of the knee and ankle muscles were performed in reaction to a visual cue to determine joint torque, rate of torque development, reaction time, and nervous activation of agonists and antagonists. Results indicated that significantly more fallers reported “dizziness upon rising”, “use of balance altering medications”, “stress or depression”, “not enough sleep”, “arthritis in lower body”, “chronic pain in lower body”, and “tiring easily while walking” (all P < 0.05). Normalized dorsiflexion and plantarflexion strength scores (summation of peak torque, rate of torque development and impulse) were lower in fallers than in nonfallers (P < 0.05). When summed across lower-extremity muscle groups, fallers demonstrated 19% lower peak torque and 29% longer motor time (P < 0.05). In conclusion, comprehensive fall risk screening and prevention programs should address both neuromuscular and non-muscular factors, and, weakness of the ankle dorsiflexors and plantarflexors should be further studied as potential contributors to falls in older adults.     

In vivo skin dose measurement using MOSkin detectors in tangential breast radiotherapy

The purpose of this study is to measure patient skin dose in tangential breast radiotherapy. Treatment planning dose calculation algorithm such as Pencil Beam Convolution (PBC) and in vivo dosimetry techniques such as radiochromic film can be used to accurately monitor radiation doses at tissue depths, but they are inaccurate for skin dose measurement. A MOSFET-based (MOSkin) detector was used to measure skin dose in this study. Tangential breast radiotherapies (“bolus” and “no bolus”) were simulated on an anthropomorphic phantom and the skin doses were measured. Skin doses were also measured in 13 patients undergoing each of the techniques. In the patient study, the EBT2 measurements and PBC calculation tended to over-estimate the skin dose compared with the MOSkin detector (p < 0.05) in the “no bolus radiotherapy”. No significant differences were observed in the “bolus radiotherapy” (p > 0.05). The results from patients were similar to that of the phantom study. This shows that the EBT2 measurement and PBC calculation, while able to predict accurate doses at tissue depths, are inaccurate in predicting doses at build-up regions. The clinical application of the MOSkin detectors showed that the average total skin doses received by patients were 1662 ± 129 cGy (medial) and 1893 ± 199 cGy (lateral) during “no bolus radiotherapy”. The average total skin doses were 4030 ± 72 cGy (medial) and 4004 ± 91 cGy (lateral) for “bolus radiotherapy”. In some cases, patient skin doses were shown to exceed the dose toxicity level for skin erythema. Hence, a suitable device for in vivo dosimetry is necessary to accurately determine skin dose.     

Colesevelam Hydrochloride Powder for Oral Suspension Versus Cholestyramine Powder for Oral Suspension: Comparison of Acceptability and Tolerability

ObjectiveTo compare tolerability of colesevelam hydrochloride powder versus a cholesterol-lowering equiv- alent dose of generic cholestyramine powder, each mixed in water, by means of the validated Bile Acid Sequestrant Acceptability(BASA) Scale.MethodsWe conducted a randomized, single-blind, single-visit, single-site study, comparing doses of 2 differ- ent bile acid sequestrant powders for oral suspension that produce similar cholesterol lowering: colesevelam hydro- chloride (3.75 g) and generic cholestyramine (12 g), each mixed in a transparent cup with tap water.ResultsThe study sample consisted of 42 partici- pants—12 men and 30 women. The study subjects were non-Hispanic white (64%) or black (36%), with a mean age of 50 years and a mean body mass index of 32.2 kg/m². The components of the BASA Scale included taste, texture, appearance, and mixability. Colesevelam hydrochloride and cholestyramine did not differ significantly when assessed by both the unweighted and the weighted global BASA Scale. Although study participants indicated that the colorless or whitish colesevelam hydrochloride pow- der tasted better (P < .0001), they thought that the orange- colored cholestyramine had a more appealing appearance (P < .0001). Regarding the potential for taking the drug “for the rest of your life, ” 71.4% of study participants rated taste as “very important, ” and 11.9% rated appearance as “very important.”ConclusionAlthough study participants thought that the orange-colored generic cholestyramine powder had a better appearance, they also reported that colesevelam hydrochloride for oral suspension tasted better. A minority of study participants thought appearance was “very impor- tant”; a substantial majority thought taste was “very impor- tant” for potential long-term compliance. (Endocr Pract. 2011;17:218-225)     

Evolution mechanism of non-hydraulic root-to-shoot signal during the anti-drought genetic breeding of spring wheat

The objectives of this study were to: (1) characterize the evolutional tendency of the non-hydraulic root-sourced signal (NRS) from wheat wild relatives to its modern hexaploid species, and (2) test whether species sensitivity to the NRS was allied with their drought tolerance profiles. The NRS was judged to begin when there was a significant lowering of stomatal conductance without change in leaf relative water content (RWC). The lethal soil water content (LSWC) was operationally characterized as the soil water content (SWC) at the drying lethal point of wheat plants. The threshold of soil water content (TSWC) at which the NRS was triggered, and the LSWC differed amongst six wheat species. For “MO1” and “MO4” representing ‘diploid’ species, the TSWC and the LSWC were initiated successively at about 51% FWC (field water capacity) and about 30% FWC, respectively. Conversely, “Plateau 602” and “Longchun 8139-2” (modern hexaploid species) exhibited the TSWC and the LSWC between about 68% FWC and less than 14% FWC, a much wider threshold range (TR). Increasing TSWC was significantly correlated with decreasing LSWC (r = 0.9464^**). The widened TR from the TSWC to the LSWC was also significantly correlated with longer survival days (SD) and higher maintenance ratio of grain yield (MRGY), respectively (r = 0.9411^** and 0.8068^*, respectively). Meanwhile, those species having higher TSWC had the least reduction ratio of stomatal conductance under the decreasing soil moisture from −0.2 to −1 MPa. This suggests that advances in yield performance and drought tolerance would be made evolutionally by targeted selection for an earlier onset of NRS.     

Performance of the Phytoplankton Index for Lakes (IPLAC): A multimetric phytoplankton index to assess the ecological status of water bodies in France

A new phytoplankton-based index was designed to respond to the Water Framework Directive (WFD) requirements concerning the assessment of lake ecological status. The “Indice Phytoplancton Lacustre” (IPLAC) is a multimetric index, taking into account biomass, abundance and species composition of communities. The first metric is based on the total phytoplankton biomass (MBA), the second on the abundance and taxonomic composition (MCS) of 165 indicator taxa. The IPLAC was developed on 2 independent databases, one for the calibration and the second for the validation of the metrics. The calibration dataset was composed of 255 “lake-years” from 214 distinct lakes sampled between 2005 and 2012. The validation dataset included 173 lake-years in order to confirm the response of the index to the trophic gradient and anthropogenic pressure.The results show that the IPLAC correctly highlights chemical pressure (eutrophication). Especially high Pearson correlations are shown with total phosphorus (r = −0.71, p-value <0.001), chlorophyll-a (r = −0.83, p-value <0.001) and water transparency (r = 0.73, p-value <0.001) which are the main proxies for the trophic level. Corine land cover was used as an indication of the anthropogenic pressure and good correlations are also found with the watershed land use, negatively correlated with agricultural area (r = −0.60, p-value <0.001), population density (r = −0.36, p-value <0.001) and positively with forest area (r = 0.57, p-value <0.001).The index is WFD-compliant and is dedicated to natural lakes and artificial water bodies in metropolitan France, and will be routinely used by the French Ministry of the Environment to assess lake ecological status through the phytoplankton community. However, the results must be carefully interpreted in two cases: reservoirs with large water level fluctuations, and samples that include less than 5 indicator species.     

Crystal structure of the pheromone Er-13 from the ciliate Euplotes raikovi,with implications for a protein–protein association model in pheromone/receptor interactions

In the ciliate Euplotes raikovi, water-borne protein pheromones promote the vegetative cell growth and mating by competitively binding as autocrine and heterologous signals to putative cell receptors represented by membrane-bound pheromone isoforms. A previously determined crystal structure of pheromone Er-1 supported a pheromone/receptor binding model in which strong protein–protein interactions result from the cooperative utilization of two distinct types of contact interfaces that arrange molecules into linear chains, and these into two-dimensional layers. We have now determined the crystal structure of a new pheromone, Er-13, isolated from cultures that are strongly mating reactive with cultures source of pheromone Er-1. The comparison between the Er-1 and Er-13 crystal structures reinforces the fundamental of the cooperative model of pheromone/receptor binding, in that the molecules arrange into linear chains taking a rigorously alternate opposite orientation reflecting the presumed mutual orientation of pheromone and receptor molecules on the cell surface. In addition, the comparison provides two new lines of evidence for a univocal rationalization of observations on the different behaviour between the autocrine and heterologous pheromone/receptor complexes. (i) In the Er-13 crystal, chains do not form layers which thus appear to be an over-structure unique to the Er-1 crystal, not essential for the pheromone signalling mechanisms. (ii) In both crystal structures, the intra-chain interfaces are equally derived from burying amino-acid side-chains mostly residing on helix-3 of the three-helical pheromone fold. This helix is thus identified as the key structural motif underlying the pheromone activity, in line with its tight intra- and interspecific structural conservation.     

Circulating levels of adipocytokine omentin-1 in patients with renal cell cancer

Renal cell carcinoma (RCC) is the fifth most common cancer worldwide, and becomes one of the leading causes of genitourinary cancer-related death in both males and females. Genetic alternations, alcohol consumption, occupationally harmful exposure and even obesity are well-established risk factors of RCC. Omentin-1 is a plasma adipokine synthesized in visceral adipose tissue, and its circulating serum concentration alters not only in conditions associated with insulin resistance such as Polycystic Ovary Syndrome (PCOS), but also in colorectal cancer and prostate cancer. To our best knowledge, the relationship between omentin-1 and RCC has not been clarified previously. Thus, we evaluated serum omentin-1 levels in RCC patients in the current matched case-control study. Forty-one patients newly diagnosed with RCC and forty-two healthy controls confirmed by the comprehensive medical examination were assessed. The omentin-1 concentrations were determined via utilizing enzyme-linked immunosorbent assays (ELISA) in the paired groups, in which the patients and healthy controls had no statistically significant differences in gender, age, systolic blood pressure (SBP), diastolic blood pressure (DBP), waist-hip ratio (WHR), estimate glomerular filtration rate (eGFR), body-mass index (BMI) and biochemical parameters. The omentin-1 levels in healthy people were 9.86 ± 1.44 ng/mL and the circulating omentin-1 levels were dramatically decreased to 3.62 ± 0.76 ng/mL in RCC patients (p < 0.001). Besides, we revealed a negative correlation between omentin-1 with WHR (r = −0.261, p = 0.017) and BMI (r = −0.310, p = 0.004), further indicating BMI was the main influential factor on omentin-1 levels (p = 0.0091). Follow-up studies would be conducted to establish the concrete mechanisms underlying the altered circulating levels of omentin-1 and elucidate the interaction between “RCC complex system” and adipose tissues, which may together provide promising and novel pharmacological insights for RCC theragnosis in the near future.     

A new data of worker polymorphism in the ant genus Dorylus (Hymenoptera: Formicidae: Dorylinae)

Recently, in southern and central Vietnam, foraging columns of D. orientalis which contained not only “typical” workers but also a few “atypical” workers were collected. The atypical worker mentioned above is characterized by a set of the following features: (1) head narrowed anteriorly, (2) median portion of clypeus strongly projecting anteriad, and (3) antenna 8-segmented. Sequences of the 658-base standard mitochondrial DNA barcoding region were completely identical between typical and atypical workers. Therefore, the condition observed was a case of worker polymorphism within a colony. The mode of polymorphism observed has the following interesting aspects: (1) workers are clearly subdivided into two series by a set of qualitative characters; (2) the “typical series” is numerically much more dominant than the “atypical series” (the latter occupied less than 1% of the whole of the workers collected); (3) a wider size variation was observed in the former (HW, 0.48–1.41 mm; ML, 0.42–1.12 mm) than in the latter (HW, 0.44–1.13 mm; ML, 0.35–0.79 mm); and (4) within the atypical series, smaller workers are numerically much dominant. Rareness of the workers belonging to the atypical series in foraging column as well as morphological differences between the two series suggests a certain possibility that the atypical series does not adapt to foraging but to other tasks in the colony's life history.     

Bio-reduction of hexachloroplatinic acid to platinum nanoparticles employing Acinetobacter calcoaceticus

Acinetobacter calcoaceticus PUCM 1011 efficiently synthesized platinum nanoparticles (PtNP) of size 2–3 nm intracellularly when challenged with hexachloroplatinic acid. Salt concentration (1 mM), temperature (30 °C), pH (7) and incubation period (72 h) influenced the efficiency of monodisperse cuboidal PtNP synthesis. Resolution of ordered lattice fringes with “d” value of 0.23 nm corresponding to (1 1 1) plane and EDAX confirmed presence of metallic platinum. AFM, TEM and HR-TEM confirmed synthesis of PtNP and its effect on cell viability. Total cell protein profile for 120 h with an interval of 24 h after PtNP synthesis revealed prominent four protein bands (97, 66, 43 and 29 kDa) when compared to control. Combinations of three proteins initiated PtNP synthesis within 4 h in range of 1–4 nm and few in picometers under HR-TEM. This is the first report of PtNP synthesis employing whole cell and total cell protein of A. calcoaceticus.     

Segmentation d’images de lésions cérébrales primitives en TEP FET : influence du volume de travail

Purpose(1) Evaluate the reproducibility of segmentation methods depending on the preselection region for tumour volume determination on ¹⁸F-fluoro-ethyl-tyrosine (FET) PET. (2) Evaluate the intra and inter-operator reproducibility of the manual delineation. (3) Compare this delineation with the segmentation methods.Materials and methodsEighteen FET PET of patients with glioblastoma were analysed. Preselection regions were determined prior to any segmentation. Two physicians delineated the tumour volume manually. The tumour volume was also delineated with a threshold method (40 and 70% of SUV_max), and a random walk based method. Pearson coefficient (r) (P < 0.05 for r > 0.468) and Jaccard indices (JI) were used to compare the volumes.ResultsManual delineation was reproducible with r = 0.97 and IJ = 0.65 for intra-operator, and r = 0.76 and IJ = 0.45 for inter-operator reproducibility. The preselection regions for a given lesion were different and the segmentation varied with the preselection region: r = 0.55 JI = 0.58; r = 0.85 JI = 0.83; r = 0.70 JI = 0.39 respectively for the threshold of 40%, 70% and the random walk. The segmentation differed form de manual delineation with r = 0.37 and JI = 0.16; r = 0.54 and JI = 0.42; r = 0.43 and JI = 0.37 respectively for the threshold of 40%, 70% and the random walk.ConclusionThe reproducibility of the segmentation methods depends extensively on the preselection region. The intra-operator reproducibility of cerebral lesion delineation on FET PET is satisfactory. The inter-operator reproducibility could be improved.     

Constraints in the identification and interpretation of ozone as a significant predictor of effects on the supersensitive indicator Nicotiana tabacum Bel-W3 in biomonitoring studies

Biomonitoring by means of the supersensitive cultivar Nicotiana tabacum Bel-W3 is frequently used to obtain information on ozone effects on plants and estimates of ozone exposure. However, most of biomonitoring surveys do not account for other environmental variables (predictors in a statistical model) and their inherent multicollinearity with ozone. We tested the relative role of different predictors (fixed: time and site; random: ozone, temperature and humidity) on height growth and on the development of visible foliar symptoms of N. tabacum Bel-W3 plants. To do this, we investigated a relatively small area (256 km²), used a random design at every stage of the survey, controlled watering and protected plants from direct solar radiation and wind. QA/QC procedures were adopted at every stage of the investigation. Linear correlation shows that Leaf Injury Index (LII) and height increment (H.I.) positively related to ozone concentration, elevation and temperature, and negatively to relative humidity. All the predictors correlate to each other. However, relationships between response and ozone vary with the site and the monitoring week. The effect of the random factor “ozone” in combination with fixed factors “site” and “time” on the response variables was therefore formally investigated using the ANCOVA model. Besides ozone, the interactions “ozone × site” and “ozone × time” resulted always significant (0.001 < P < 0.05). While the factor “time” emphasize the inherent development of injury and growth through time, the interaction “ozone × site” pointed out the importance of local conditions. When watering, solar radiation, wind and plant characteristics were controlled, the remaining site-specific covariates of interest were temperature (T) and humidity (RH). When T and RH were accounted for by means of partial correlation analysis, no significant relationship was found between ozone and LII. On the other side, O₃ and RH resulted significant for both absolute and relative height increment. In short, LII seemed to be not solely dependent on ozone, T and RH, but showed to integrate their combined effect. On the other side, H.I. seemed to be favoured by high RH and T, and depressed by high ozone. Based on the above results, we recommend caution when handling bioindicator data: if the purpose is to infer ozone concentrations by leaf injury data, results may be affected by a serious bias, as the frequently reported correlations may be partly an artefact due to co-variation between predictors.     

Relationships among udder characteristics,milk yield and,non-yield traits in Frizarta dairy sheep

In the present study the relationships between five body structural and nine udder morphological traits with milk yield and non-yield traits, i.e. milk contents, somatic cell count and body weight in n = 171 Frizarta ewes were investigated. Positive correlations of moderate to high magnitude were observed among body measurements ranging from 0.25 (body length-chest width) to 0.61 (chest width-chest girth). High correlations were observed between udder width and udder circumference (r = 0.69) as well as between udder circumference at base and middle (r = 0.62). Udder height was found to be positively correlated with cistern depth (r = 0.32), udder width (r = 0.40) and udder circumference (r = 0.42) as well as with teat measurements (0.19 and 0.25 with teat length and teat circumference, respectively). Cistern depth was positively and highly correlated with teat angle (r = 0.64). The correlation between teat length and circumference was also high (r = 0.57). Teat angle was found to be negatively correlated with teat measurements (r = −0.39 and −0.23 for teat length and teat circumference, respectively). Principal components analysis revealed four components that jointly explained 67% of the variance of all the body and the udder morphological traits. The first principal component interpreted as the body dimensions was found to be associated with body weight of ewes. The second component interpreted as global and rear measurements of the udder was significant for milk yield traits. The third and fourth principal components were interpreted as the udder type and teat dimensions, respectively. Ewes’ body weight could be adequately predicted by chest girth, body length, chest width and withers height. Test day milk yields were found to be associated with udder circumference and udder width as well as with udder height and teat length. None of the udder measurements and/or teat characteristics was found to be correlated with milk content(s) and/or somatic cell count. New statistical techniques can be successfully implemented in investigation of relationships between various traits in dairy sheep.     

An avifaunal survey of mesic manmade ecosystems “Oases” in algerian hot-hyperarid lands

Man made ecosystems of dry lands are key habitats due to their ecological characteristics to survey biodiversity. This study investigated bird diversity in three oases of the Northern Algerian Sahara (i.e., Biskra in 2006, Oued Souf in 2008 and Ouargla in 2009), by using the spot-mapping method. Bird density “D” (pairs/10 ha), species richness “S” (number species), diversity (Shannon index) “H′” (in bits), and evenness “E” varied from one oasis to another (Biskra: D = 98.5, S = 47, H′ = 4.49, E = 0.81; Oued Souf: D = 96, S = 33, H′ = 3.9, E = 0.77; Ouargla: D = 91.5, S = 44, H′ = 4.39, E = 0.80). Differences in bird diversity between the monitored palm groves are due to the ecological characteristics of each environment. Documented literature outlined close taxonomic similarities between bird assemblages of the study area with many Northern Saharan oases. The Hybrid Sparrow Passer domesticus x Passer. hispaniolensis and some Columbidae species including Columba livia, Streptopelia turtur, Streptopelia senegalensis, and Streptopelia decaocto were the abundant species throughout surveyed oases in which they represented more than half (55.6%) of the sum of species densities (D = 286 pairs/10 ha). These synthropic species have known a huge expansion of their distribution range throughout Algerian oases. The correspondence analysis allowed the aggregation of both families and species into oasis they belong to. One-way ANOVA was tested to analyse variations of both family and species densities between studied oases. The ANOVA revealed there was no significant variation either in family densities (p = 0.937) or in bird densities (p = 0.622) between the surveyed oases because of the small size of bird populations.     

Relationship between zinc levels and plasma leptin in hemodialysis patients

Recent evidences suggested a possible relationship between zinc deficiency and leptin levels in pathogenesis of anorexia in chronic kidney disease. The present study addressed the relationship between zinc and leptin in hemodialysis (HD) patients.MethodsFifty HD patients (54.3 ± 12.7 years old, 62% men) were studied and compared to 21 healthy volunteers (50.7 ± 15.7 years old, 43% men). Biochemical data, serum zinc, plasma leptin, IL-6, TNF-α and C-Reactive Protein levels were determined. Anthropometric parameters, food intake and appetite score were also assessed.ResultsThe leptin levels were higher in HD patients (16.1 μg/mL (0.21–118.25) vs 6.0 μg/mL (0.50–23.10)) in healthy volunteers (p = 0.04), whereas serum zinc levels were lower (54.5 ± 16.3 μg/dL) compared to healthy volunteers (78.4 ± 9.4 μg/dL) (p = 0.0001). The plasma leptin was correlated negatively with plasma zinc (r = ?0.33; p = 0.007), energy (r = ?0.38; p = 0.002) and protein intake (r = ?0.34; p = 0.006) and, positively correlated with BMI (r = 0.54; p = 0.0001), % body fat (r = 0.70; p = 0.0001) and conicity index (r = 0.46; p = 0.001). Plasma zinc was associated with hemoglobin (r = 0.30; p = 0.04) and negatively associated with TNF-α (r = ?0.37; p = 0.002) and C-Reactive Protein (r = ?0.37; p = 0.004). There was no correlation among Zn, leptin and appetite score in these patients.ConclusionThis study showed that low plasma zinc levels are negatively associated with high leptin levels in HD patients.