Mitochondrial and Nuclear Genes-Based Phylogeography of Arvicanthis niloticus (Murinae) and Sub-Saharan Open Habitats Pleistocene History

A phylogeographic study was conducted on the Nile grass rat, Arvicanthis niloticus, a rodent species that is tightly associated with open grasslands from the Sudano-Sahelian regions. Using one mitochondrial (cytochrome b) and one nuclear (intron 7 of Beta Fibrinogen) gene, robust patterns were retrieved that clearly show that (i) the species originated in East Africa concomitantly with expanding grasslands some 2 Ma, and (ii) four parapatric and genetically well-defined lineages differentiated essentially from East to West following Pleistocene bioclimatic cycles. This strongly points towards allopatric genetic divergence within savannah refuges during humid episodes, then dispersal during arid ones; secondary contact zones would have then stabilized around geographic barriers, namely, Niger River and Lake Chad basins. Our results pertinently add to those obtained for several other African rodent as well as non-rodent species that inhabit forests, humid zones, savannahs and deserts, all studies that now allow one to depict a more comprehensive picture of the Pleistocene history of the continent south of the Sahara. In particular, although their precise location remains to be determined, at least three Pleistocene refuges are identified within the West and Central African savannah biome.     

Association between Gestational Weight Gain and Postpartum Diabetes: Evidence from a Community Based Large Cohort Study

We have investigated the prospective association between excess gestational weight gain (GWG) and development of diabetes by 21 years post-partum using a community-based large prospective cohort study in Brisbane, Australia. There were 3386 mothers for whom complete data were available on GWG, pre-pregnancy BMI and self-reported diabetes 21 years post-partum. We used The Institute of Medicine (IOM) definition to categorize GWG as inadequate, adequate and excessive. We found 839 (25.78%) mothers gained inadequate weight, 1,353 (39.96%) had adequate weight gain and 1,194 (35.26%) had gained excessive weight during pregnancy. At 21 years post-partum, 8.40% of mothers self-reported a diagnosis of diabetes made by their doctor. In the age adjusted model, we found mothers who gained excess weight during pregnancy were 1.47(1.11,1.94) times more likely to experience diabetes at 21 years post-partum compared to the mothers who gained adequate weight. This association was not explained by the potential confounders including maternal age, parity, education, race, smoking, TV watching and exercise. However, this association was mediated by the current BMI. There was no association for the women who had normal BMI before pregnancy and gained excess weight during pregnancy. The findings of this study suggest that women who gain excess weight during pregnancy are at greater risk of being diagnosed with diabetes in later life. This relationship is likely mediated through the pathway of post-partum weight-retention and obesity. This study adds evidence to the argument that excessive GWG during pregnancy for overweight mothers has long term maternal health implications.     

A serological survey of selected pathogens in wild boar (<Emphasis Type="Italic">Sus scrofa</Emphasis>) in northern Turkey

During the hunting season in March 2012, a total of 93 blood samples were collected from wild boars (Sus scrofa) shot in the area of northern Turkey (Samsun and Gumushane provinces). These blood samples were examined by enzyme immunoassay (ELISA) for the presence of antibodies to classical swine fever virus (CSFV), Aujeszky’s disease virus (ADV), porcine reproductive and respiratory syndrome virus (PRRSV), porcine respiratory coronavirus (PRCV), swine influenza virus (SIV), porcine parvovirus (PPV), swine vesicular disease virus (SVDV), hepatitis E virus (HEV), African swine fever virus (ASFV), porcine rotavirus (PRV), transmissible gastroenteritis virus (TGEV) and bovine viral diarrhoea virus (BVDV). Out of 93 serum samples examined, 65 (69.9 %) were positive for PRV, 22 (23.7 %) were positive for ADV, 5 (5.4 %) were positive for BVDV, 4 (4.3 %) were positive for PPV and 2 (2.2 %) were positive for PRRSV. All sera were negative for ASFV, SVDV, HEV, SIV, PRCV, TGEV and CSFV. The results, recorded for the first time in Turkey, supported the hypothesis that wild boar act as a potential reservoir of selected viruses and thus have a role in the epidemiology of these diseases.     

Decrease of theta response in euthymic bipolar patients during an oddball paradigm

Theta oscillations are related to cognitive functions and reflect functional integration of frontal and medial temporal structures into coherent neurocognitive networks. This study assessed event-related theta oscillations in medication-free, euthymic patients with bipolar disorder upon auditory oddball paradigm. Twenty-two DSM-IV euthymic bipolar I (n = 19) and II (n = 3) patients and twenty-two healthy subjects were included. Patients were euthymic for at least 6 months, and psychotropic-free for at least 2 weeks. EEG was recorded at 30 electrode sites. Auditory oddball paradigm and sensory stimuli were used. Event-related Oscillations were analyzed using adaptive filtering in two different theta frequency bands (4–6 Hz, 6–8 Hz). In healthy subjects, slow theta (4–6 Hz) responses were significantly higher than those of euthymic patients upon target, non-target and sensory stimuli (p < 0.05). Fast theta (6–8 Hz) responses of healthy subjects were significantly higher than those of euthymic patients upon target-only stimuli (p < 0.05). Reduced theta oscillations during auditory processing provide strong quantitative evidence of activation deficits in related networks in bipolar disorder. Fast theta responses are related to cognitive functions, whereas slow theta responses are related to sensory processes more than cognitive processes.     

Association of multiple drug resistance-1 gene polymorphism with multiple drug resistance in breast cancer patients from an ethnic Saudi Arabian population

Chemotherapy has been used widely to treat cancer, both as a systemic therapy and as a local treatment. Unfortunately, many types of cancer are still refractory to chemotherapy. The mechanisms of anticancer drug resistance have been extensively explored but have not been fully characterized. This study analyzed the occurrences of polymorphism (SNP) in the MDR1 gene in breast cancer patients and determined a possible association with chemotherapy. The study group included one hundred breast carcinoma patients who subsequently received chemotherapy (the regimen generally consisted of commonly used drugs such as cyclophosphamide, adriamycin, 5-fluorouracil, docetaxel and their combinations). Blood samples from 100 healthy individuals are used, as controls were also genotyped for the MDR1 gene. This investigation revealed a significant correlation with response to various regimens of chemotherapy showing a low response to therapy with the CT/TT genotype at (exon 12) 1236 codon (p < 0.001). These findings demonstrate, for the first time, that the polymorphisms in (exon 12) 1236 codon of the MDR1 gene greatly influence the drug response in patients from the Arab population of Saudi Arabia.     

Aspirin Use and Risk of Age-Related Macular Degeneration: A Meta-Analysis

Background

Age-related macular degeneration (AMD) is the main cause of blindness and the curative options are limited. The objective of this meta-analysis was to determine the association between aspirin use and risk of AMD.

Methods

A comprehensive literature search was performed in PubMed, Embase, Web of Science, and reference lists. A meta-analysis was performed by STATA software.

Results

Ten studies involving 171729 individuals examining the association between aspirin use and risk of AMD were included. Among the included studies, 2 were randomized-controlled trials (RCTs), 4 were case-control studies and 4 were cohort studies. The relative risks (RRs) were pooled using a random-effects model. Relative risks with 95% confidence intervals (CIs) of aspirin use as a risk for AMD. The pooled RR of 10 included studies between the use of aspirin and risk of AMD was 1.09 (95% CI, 0.96–1.24). The same result was detected in early and late stage AMD subgroup analysis. In the subgroup analyses, the pooled RR of RCTs, case-control studies and cohort studies were 0.81 (95% CI, 0.64–1.02), 1.02 (95% CI, 0.92–1.14) and 1.08 (95% CI, 0.91–1.28), respectively.

Conclusions

The use of aspirin was not associated with the risk of AMD.     

Middle Palaeolithic and Neolithic Occupations around Mundafan Palaeolake,Saudi Arabia: Implications for Climate Change and Human Dispersals

The Arabian Peninsula is a key region for understanding climate change and human occupation history in a marginal environment. The Mundafan palaeolake is situated in southern Saudi Arabia, in the Rub’ al-Khali (the ‘Empty Quarter’), the world’s largest sand desert. Here we report the first discoveries of Middle Palaeolithic and Neolithic archaeological sites in association with the palaeolake. We associate the human occupations with new geochronological data, and suggest the archaeological sites date to the wet periods of Marine Isotope Stage 5 and the Early Holocene. The archaeological sites indicate that humans repeatedly penetrated the ameliorated environments of the Rub’ al-Khali. The sites probably represent short-term occupations, with the Neolithic sites focused on hunting, as indicated by points and weaponry. Middle Palaeolithic assemblages at Mundafan support a lacustrine adaptive focus in Arabia. Provenancing of obsidian artifacts indicates that Neolithic groups at Mundafan had a wide wandering range, with transport of artifacts from distant sources.     

Factors Controlling the Redox Potential of ZnCe6 in an Engineered Bacterioferritin Photochemical ‘Reaction Centre’

Photosystem II (PSII) of photosynthesis has the unique ability to photochemically oxidize water. Recently an engineered bacterioferritin photochemical ‘reaction centre’ (BFR-RC) using a zinc chlorin pigment (ZnCe₆) in place of its native heme has been shown to photo-oxidize bound manganese ions through a tyrosine residue, thus mimicking two of the key reactions on the electron donor side of PSII. To understand the mechanism of tyrosine oxidation in BFR-RCs, and explore the possibility of water oxidation in such a system we have built an atomic-level model of the BFR-RC using ONIOM methodology. We studied the influence of axial ligands and carboxyl groups on the oxidation potential of ZnCe₆ using DFT theory, and finally calculated the shift of the redox potential of ZnCe₆ in the BFR-RC protein using the multi-conformational molecular mechanics–Poisson-Boltzmann approach. According to our calculations, the redox potential for the first oxidation of ZnCe₆ in the BRF-RC protein is only 0.57 V, too low to oxidize tyrosine. We suggest that the observed tyrosine oxidation in BRF-RC could be driven by the ZnCe₆ di-cation. In order to increase the efficiency of tyrosine oxidation, and ultimately oxidize water, the first potential of ZnCe₆ would have to attain a value in excess of 0.8 V. We discuss the possibilities for modifying the BFR-RC to achieve this goal.     

The relationships between fish size and otolith dimensions in the common sole (Solea solea (Linnaeus, 1758)) captured in the Northeastern Mediterranean

Fish specimens were captured by a commercial bottom trawler at a depth of 50–80 m from Iskenderun Bay (Hatay, Turkey) between December 2017 and May 2018. The bottom trawl gear used was equipped with a 44 mm stretched mesh size net at the cod-end. Blind side and eyed side otolith lengths (OL), otolith breadths (OB) and otolith weights (OW) were measured from each specimen to the nearest 0.001 mm and 0.0001g respectively. A total of 110 fish (43 females and 67 males) were collected. Total length ranged from 20.8 to 28.2 cm and 68.0 to 166.1 g (males) and 21.1 to −28.5 cm and 74.5 to 201.4 g (females). The coefficients of determination between fish weight and otolith weight, and total length and otolith weight (sexes combined) were found as R² = .7694 (0.77) and R² = .6274 (0.63), respectively. A moderate positive relationship between the total length-otolith dimensions, and fish weight-otolith dimensions, was also demonstrated.