Climate change and animals in Saudi Arabia

Global warming is occurring at an alarming rate and predictions are that air temperature (T_a) will continue to increase during this century. Increases in T_a as a result of unabated production of greenhouse gases in our atmosphere pose a threat to the distribution and abundance of wildlife populations worldwide. Although all the animals worldwide will likely be affected by global warming, diurnal animals in the deserts will be particularly threatened in the future because T_as are already high, and animals have limited access to water. It is expected that Saudi Arabia will experience a 3–5 °C in T_a over the next century. For predicting the consequences of global warming for animals, it is important to understand how individual species will respond to higher air temperatures. We think that populations will not have sufficient time to make evolutionary adjustments to higher T_a, and therefore they will be forced to alter their distribution patterns, or make phenotypic adjustments in their ability to cope with high T_a. This report examines how increases in T_a might affect body temperature (T_b) in the animals of arid regions. We chose three taxonomic groups, mammals, birds, and reptiles (Arabian oryx, Arabian spiny-tailed lizard, vultures, and hoopoe larks) from Saudi Arabia, an area in which T_a often reaches 45 °C during midday in summer. When T_a exceeds T_b, animals must resort to behavioral and physiological methods to control their T_b; failure to do so results in death. The observations of this study show that in many cases T_b is already close to the upper lethal limit of around 47° C in these species and therefore allowing their T_b to increase as T_a increases are not an option. We conclude that global warming will have a detrimental impact on a wide range of desert animals, but in reality we know little about the ability of most animals to cope with change in T_a. The data presented should serve as base-line information on T_b of animals in the Kingdom for future scientists in Saudi Arabia as they explore the impact of global warming on animal species.     

p53 Codon 72 arginine/proline polymorphism and cancer in Sudan

The aim of this report is to determine frequencies and associations of p53 codon 72 arg/pro polymorphism with different types of cancer in Sudan. p53 codon72 arg/pro polymorphism distribution and allele frequencies in 264 samples of different types of cancers were investigated using PCR. The results were compared to 235 normal controls. The results indicated significant differences in frequency and genotype association between different types of cancers. Breast carcinoma patients most prominently showed excess of homozygous arg genotype as compared to controls with an Odd ratio (OR) of 19.44, 95?%CI: 6.6–78.3, P?<?0.0001. Less prominently cervical cancer showed genotype effect of 2.4 OR, 95?%CI: 1.12–5.33, P?=?0.015, while esophageal cancer had an OR of 0.57, 95?%CI: 0.23–1.42, P?=?0.1. In Burkitt’s lymphoma, however, in contrast the homozygous arg accounted for only 6.9?%, (OR 0.18, 95?%CI: 0.02–0.89, P?=?0.018). We concluded that p53 arg/pro polymorphism has different pattern of frequency in different types of cancer among Sudanese patients, indicating perhaps different etiology and biology of these tumours.     

Homeotic Arm-to-Leg Transformation Associated with Genomic Rearrangements at the PITX1 Locus

The study of homeotic-transformation mutants in model organisms such as Drosophila revolutionized the field of developmental biology, but how these mutants relate to human developmental defects remains to be elucidated. Here, we show that Liebenberg syndrome, an autosomal-dominant upper-limb malformation, shows features of a homeotic limb transformation in which the arms have acquired morphological characteristics of a leg. Using high-resolution array comparative genomic hybridization and paired-end whole-genome sequencing, we identified two deletions and a translocation 5′ of PITX1. The structural changes are likely to remove active PITX1 forelimb suppressor and/or insulator elements and thereby move active enhancer elements in the vicinity of the PITX1 regulatory landscape. We generated transgenic mice in which PITX1 was misexpressed under the control of a nearby enhancer and were able to recapitulate the Liebenberg phenotype.     

Evaluating ring-tailed lemurs (Lemur catta) from southwestern Madagascar for a genetic population bottleneck

In light of historical and recent anthropogenic influences on Malagasy primate populations, in this study ring-tailed lemur (Lemur catta) samples from two sites in southwestern Madagascar, Beza Mahafaly Special Reserve (BMSR) and Tsimanampetsotsa National Park (TNP), were evaluated for the genetic signature of a population bottleneck. A total of 45 individuals (20 from BMSR and 25 from TNP) were genotyped at seven microsatellite loci. Three methods were used to evaluate these populations for evidence of a historical bottleneck: M-ratio, mode-shift, and heterozygosity excess tests. Three mutation models were used for heterozygosity excess tests: the stepwise mutation model (SMM), two-phase model (TPM), and infinite allele model (IAM). M-ratio estimations indicated a potential bottleneck in both populations under some conditions. Although mode-shift tests did not strongly indicate a population bottleneck in the recent historical past when samples from all individuals were included, a female-only analysis indicated a potential bottleneck in TNP. Heterozygosity excess was indicated under two of the three mutation models (IAM and TPM), with TNP showing stronger evidence of heterozygosity excess than BMSR. Taken together, these results suggest that a bottleneck may have occurred among L. catta in southwestern Madagascar in the recent past. Given knowledge of how current major stochastic climatic events and human-induced change can negatively impact extant lemur populations, it is reasonable that comparable events in the historical past could have caused a population bottleneck. This evaluation additionally functions to highlight the continuing environmental and anthropogenic challenges faced by lemurs in southwestern Madagascar.     

Cyanide degradation by immobilized cells of Rhodococcus UKMP-5M

Anthropogenic sources contribute to the bulk presence of cyanide, which causes substantial health and environmental concerns. A petroleum-contaminated soil isolate, Rhodococcus UKMP-5M has been verified to efficiently degrade high concentration of cyanide in the form of KCN in our previous study. In order to enhance the cyanide-degrading ability of this bacterium, different encapsulation matrices were screened to immobilize cells of Rhodococcus UKMP-5M for degradation of cyanide. It was revealed that the biocatalyst activity and bead mechanical strength improved significantly when calcium alginate encapsulation technique was employed as compared to free cells. The results also indicated that the immobilized cell system could tolerate a higher level of KCN concentration and were able to support a higher biomass density. In addition, the embedded cells retained almost 96% of their initial cyanide removal efficiency during the first five batches and the entrapped cell system maintained 64% of its initial activity after eight successive batches. The encapsulated beads could be easily recovered from the production medium and reused for up to five batches without significant losses of cyanide-degrading ability, which proved to be advantageous from an economic point of view. From this study, it could be inferred that the novel Rhodococcus UKMP-5M strain demonstrated high cyanide-degrading ability and the optimized calcium alginate immobilization technique provided a promising alternative for practical application of large scale remediation of cyanide-bearing wastewaters.     

Exhaled volatile organic compounds for phenotyping chronic obstructive pulmonary disease: a cross-sectional study

Background

Non-invasive phenotyping of chronic respiratory diseases would be highly beneficial in the personalised medicine of the future. Volatile organic compounds can be measured in the exhaled breath and may be produced or altered by disease processes. We investigated whether distinct patterns of these compounds were present in chronic obstructive pulmonary disease (COPD) and clinically relevant disease phenotypes.

Methods

Breath samples from 39 COPD subjects and 32 healthy controls were collected and analysed using gas chromatography time-of-flight mass spectrometry. Subjects with COPD also underwent sputum induction. Discriminatory compounds were identified by univariate logistic regression followed by multivariate analysis: 1. principal component analysis; 2. multivariate logistic regression; 3. receiver operating characteristic (ROC) analysis.

Results

Comparing COPD versus healthy controls, principal component analysis clustered the 20 best-discriminating compounds into four components explaining 71% of the variance. Multivariate logistic regression constructed an optimised model using two components with an accuracy of 69%. The model had 85% sensitivity, 50% specificity and ROC area under the curve of 0.74. Analysis of COPD subgroups showed the method could classify COPD subjects with far greater accuracy. Models were constructed which classified subjects with ≥2% sputum eosinophilia with ROC area under the curve of 0.94 and those having frequent exacerbations 0.95. Potential biomarkers correlated to clinical variables were identified in each subgroup.

Conclusion

The exhaled breath volatile organic compound profile discriminated between COPD and healthy controls and identified clinically relevant COPD subgroups. If these findings are validated in prospective cohorts, they may have diagnostic and management value in this disease.     

Tomato powder impedes the development of azoxymethane-induced colorectal cancer in rats through suppression of COX-2 expression via NF-κB and regulating Nrf2/HO-1 pathway

Cancer is one of the leading causes of death worldwide. Since dietary factors have been connected to a reduced risk of a diversity of human cancers, in this study we investigated the effects of tomato powder (TP) on the development of azoxymethane (AOM)-induced colorectal cancer in Wistar rats, and possible mechanism(s) by which TP shows its chemopreventive activity. Here we show that TP added to feed at 5% rate decreases the rate of aberrant crypt foci (ACF) and reduces the development of adenocarcinoma and growth of AOM-induced colorectal cancer in rats. In addition, we demonstrate that TP supplementation shows its chemopreventive activities through inhibition of cyclooxygenase-2 (COX-2) expression via NF-κB pathway and promotion of apoptosis, as well as regulating Nrf2/HO-1 signaling pathway in colorectal tissue of AOM-treated rats. Our findings identify an intimate connection between dietary supplementation of TP and the decreased risk of colorectal cancer in rats, and suggest that consumption of TP would be a natural candidate for the prevention of colorectal cancer in men.     

Biological Assessment of Water Pollution Using Periphyton Productivity and Standing Crop in the Linggi River,Malaysia

Many assessments of water pollution in aquatic ecosystem have focused mainly on physical and chemical characteristics. However, until recently, biological aspects have been given little attention. Although physical and chemical methods of assessing water pollution are relatively simple to interpret, biological assessments have many strong merits. Therefore an attempt was made to use periphyton productivity (in terms of biomass ash‐free dry weight, AFDW) and chlorophyll‐a content (measured from periphyton colonized on glass microscope slides) to assess water pollution in the Linggi river. The Linggi River is a tropical lotic system in the country of Malaysia. As a result of increased nutrient enrichment due to sewage and agro‐industrial wastes, analyses of accumulated periphyton on glass slides showed increased biomass AFDW from an unpolluted upstream reach to the highly polluted downstream reach of the river. In contrast to biomass, the chlorophyll‐a content of the accumulated periphyton was not always directly related to the AFDW of the biomass. Though the highly polluted Station 4 showed high biomass AFDW and chlorophyll‐a, due to increased nutrient enrichment. The chlorophyll‐a values at slightly polluted Station 2 were lower than at the unpolluted Station 1. Meanwhile, the mean chlorophyll‐a content observed in Linggi river was relatively high as compared to previous studies carried out in Malaysia. When the Water Quality Index (WQI) was calculated using key chemical parameters linked to organic pollution, there was a significant correlation between chemical parameters, biomass AFDW, and chorophyll‐a. Though the chlorophyll‐a content increased with decreases in the WQI, similar to the biomass AFDW, the chlorophyll‐a values were found to be lower in slightly polluted Station 2 than unpolluted Station 1. Therefore it was not necessary that an increase in the biomass AFDW, due to nutrient enrichment, would always increase the chlorophyll‐a in accumulated periphyton (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)