Association of glutathione S-transferase polymorphisms (GSTM1 and GSTT1) with primary open-angle glaucoma: An evidence-based meta-analysis

Studies investigating the associations between glutathione S-transferase (GST) genetic polymorphisms and primary open-angle glaucoma (POAG) have reported controversial results. Therefore, a meta-analysis was performed to clarify the effects of GSTM1 and GSTT1 polymorphisms on POAG risk. Published literatures from PubMed, EMBASE, ISI Web of Science and CBM databases were retrieved. All studies evaluating the association between GSTM1/GSTT1 polymorphisms and POAG were included. Pooled odds ratio (OR) and 95% confidence interval (CI) were calculated using fixed- or random-effects model. Eleven studies on GSTM1 (1339 cases and 1412 controls) and seven studies on GSTT1 (958 cases, 1003 controls) were included. Overall analysis showed that the association between GSTM1 and GSTT1 null genotype and POAG risk is not statistically significant. Subgroup analyses showed that the null genotype of GSTM1 increased the risk of POAG in Asians. In GSTM1–GSTT1 interaction analysis, individuals with dual null genotype were associated with a significantly increased risk of POAG when compared with the dual present genotype. In conclusion, the present meta-analysis suggested that GSTM1 null genotypes are associated with increased POAG risk in Asian populations but not in Caucasian and mixed populations. Dual null genotype of GSTM1/GSTT1 is associated with increased risk of POAG. Given the limited sample size, the finding on GST polymorphisms needs further investigation.     

Neurologically normal development of a patient with severe methionine adenosyltransferase I/III deficiency after continuing dietary methionine restriction

Background

There is not much information on established standard therapy for patients with severe methionine adenosyltransferase (MAT) I/III deficiency.

Case presentation

We report a boy with MAT I/III deficiency, in whom plasma methionine and total homocysteine, and urinary homocystine were elevated. Molecular genetic studies showed him to have novel compound heterozygous mutations of the MAT1A gene: c.191T>A (p.M64K) and c.589delC (p.P197LfsX26). A low methionine milk diet was started at 31 days of age, and during continuing dietary methionine restriction plasma methionine levels have been maintained at less than 750 μmol/L. He is now 5 years old, and has had entirely normal physical growth and psychomotor development.

Conclusions

Although some severely MAT I/III deficient patients have developed neurologic abnormalities, we report here the case of a boy who has remained neurologically and otherwise normal for 5 years during methionine restriction, suggesting that perhaps such management, started in early infancy, may help prevent neurological complications.     

The relationship between the presence of ADHD and certain candidate gene polymorphisms in a Turkish sample

Due to the high heritability of attention-deficit hyperactivity disorder (ADHD), parents of children with ADHD appear to represent a good sample group for investigating the genetics of the disorder. The aim of this study was to investigate the association between ADHD and six polymorphisms in five candidate genes [5-HT2A (rs6311), NET1 (rs2242447), COMT (rs4818), NTF3 (rs6332), SNAP-25 (rs3746544) and (rs1051312)]. We included 228 parents of children diagnosed with ADHD and 109 healthy parents as the control group. The polymorphisms were genotyped using polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) assays and analyzed using the chi-square test and the multinomial logit model. SNAP-25 (rs3746544) polymorphism was associated with loading for ADHD, while 5-HT2A (rs6311) and NET1 (rs2242447) polymorphisms were associated with ADHD. On the other hand, there was no significant association between the SNAP-25 (rs1051312), NTF3 (rs6332), or COMT (rs4818) gene polymorphisms and ADHD.     

The association between glycogen synthase kinase 3 beta polymorphisms and Parkinson's disease susceptibility: A meta-analysis

Previous studies on the association between glycogen synthase kinase 3 beta (GSK3-β) polymorphisms (rs334558 and rs6438552) and Parkinson's disease (PD) susceptibility remained inconsistent. Thus, the goal of this study was to re-examine their exact association by a meta-analysis. All eligible studies were identified by a systematic literature search of multiple databases. Six studies (3105 cases and 4387 controls) on rs334558 and six studies (2579 cases and 4091 controls) on rs6438552 were included. The quality of these studies was generally good according to the Newcastle–Ottawa Scale (NOS). The meta-analysis showed null association between the two variants and PD susceptibility in all genetic models from the overall or Caucasian population. However, the analysis of rs334558 revealed that the risk of PD decreased in heterozygote, dominant or additive models (OR = 0.60, 95% CI: 0.48, 0.74; OR = 0.63, 95% CI: 0.51, 0.78; OR = 0.82, 95% CI: 0.71, 0.94, respectively) from the Eastern Asian population. Moreover, the analysis on the homozygote, heterozygote, dominant or additive models suggested that rs6438552 also reduced the PD risk (OR = 0.45, 95% CI: 0.24, 0.84; OR = 0.62, 95% CI: 0.39, 0.97; OR = 0.57, 95% CI: 0.37, 0.87; OR = 0.66, 95% CI: 0.49, 0.88, respectively) in the Eastern Asian population. Together, the findings suggest that the two variants both reduced the risk of PD in the Eastern Asian subgroup but not in the overall and Caucasian populations, which should be cautiously interpreted because of limited number of included studies.     

Sleep and Sleepiness of Fishermen on Rotating Schedules

Seafaring is a hazardous occupation with high death and injury rates, but the role of seafarer fatigue in these events is generally not well documented. The International Maritime Organization has identified seafarer fatigue as an important health and safety issue. Most research to date has focused on more regularly scheduled types of operations (e.g., merchant vessels, ferries), but there is relatively little information on commercial fishing, which often involves high day‐to‐day and seasonal variability in work patterns and workload. The present study was designed to monitor the sleep and sleepiness of commercial fishermen at home and during extended periods at sea during the peak of the hoki fishing season, with a view to developing better fatigue management strategies for this workforce. Sleep (wrist actigraphy and sleep diaries) and sleepiness (Karolinska Sleepiness Scale [KSS] before and after each sleep period) of 20 deckhands were monitored for 4–13 days at home and for 5–9 days at sea while working a nominal 12 h on/6 h off schedule. On the 12 h on/6 h off schedule, there was still a clear preference for sleep at night. Comparing the last three days at home and the first three days at sea showed that fishermen were more likely to have split sleep at sea (Wilcoxon signed ranks p<0.001), but the median sleep/24 h did not differ significantly by location (5.9 h at sea vs. 6.7 h at home). However, on 23% of days at sea, fishermen obtained<4 h total sleep/24 h, compared to 3% of days at home (p(χ²)<0.01). Sleep efficiency, mean activity counts/min sleep, and subjective ratings of sleep quality did not differ significantly between the last three days at home and the first three days at sea. However, sleepiness ratings remained higher after sleep at sea (Wilcoxon signed ranks p<0.05), with fishermen having post‐sleep KSS ratings ≥7 on 24% of days at sea vs. 9% of days at home (Wilcoxon signed ranks p<0.01). This work adds to the limited number of studies that objectively monitored the sleep of seafarers. It has the strength of operational fidelity but the weakness that large inter‐ and intra‐individual variability in sleep, combined with the small sample size, limited the power of the study to detect statistically significant differences between sleep at home and at sea. The clear preference for sleep at night during the 12 h on/6 h off schedule at sea is consistent with the expectation that this 18 h duty/rest cycle is outside the range of entrainment of the circadian pacemaker. High levels of acute sleep loss, and residual sleepiness after sleep, were much more common at sea than at home. The longer duration of trips during the peak of the fishing season increases the risk of performance impairment due to greater cumulative sleep loss than would be expected on typical three‐day trips. Key fatigue management strategies in this environment include that fishermen report to work as well rested as possible. Once at sea, the day‐to‐day variability in activities due to uncontrollable factors, such as fishing success, repairing gear, and weather conditions, mean that contingency planning is required for managing situations where the entire crew have experienced long periods of intensive work with minimum recovery opportunities.     

Blend miscibility of cellulose propionate with poly(N-vinyl pyrrolidone-co-methyl methacrylate)

The blend miscibility of cellulose propionate (CP) with poly(N-vinyl pyrrolidone-co-methyl methacrylate) (P(VP-co-MMA)) was investigated. The degree of substitution (DS) of CP used ranged from 1.6 to >2.9, and samples for the vinyl polymer component were prepared in a full range of VP:MMA compositions. Through DSC analysis and solid-state ¹³C NMR and FT-IR measurements, we revealed that CPs of DS < 2.7 were miscible with P(VP-co-MMA)s of VP ≥ ∼10 mol% on a scale within a few nanometers, in virtue of hydrogen-bonding interactions between CP-hydroxyls and VP-carbonyls. When the DS of CP exceeded 2.7, the miscibility was restricted to the polymer pairs using P(VP-co-MMA)s of VP = ca. 10–40 mol%; the scale of mixing in the blends concerned was somewhat larger (ca. 5–20 nm), however. The appearance of such a “miscibility window” was interpretable as an effect of intramolecular repulsion in the copolymer component. Results of DMA and birefringence measurements indicated that the miscible blending of CP with the vinyl polymer invited synergistic improvements in thermomechanical and optical properties of the respective constituent polymers. Additionally, it was found that the VP:MMA composition range corresponding to the miscibility window was expanded by modification of the CP component into cellulose acetate propionate.     

Patterns of density dependence in growth,reproduction and survival in the invasive freshwater snail Pomacea canaliculata in Japanese rice fields

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A bioenergetic assessment of the influence of stocking practices on rainbow trout (Oncorhynchus mykiss) growth and consumption in a New Zealand lake

Summary

• 1 To investigate the carrying capacity and factors affecting growth of rainbow trout in Lake Rotoiti, we employed a bioenergetics model to assess the influence of stocking rates, timing of releases and prey abundance on growth and prey consumption. We hypothesised that stocking rates and prey abundance would affect growth and prey consumption by influencing per‐capita prey availability, and that the environmental conditions encountered by fish at the time of stocking would affect growth and consumption.
• 2 Prey consumption of stocked rainbow trout was calculated with the Wisconsin bioenergetics model. We calculated growth trajectories of released trout based on data from stocked trout that were released in spring and autumn from 1993 to 2009 and then re‐captured by anglers. Diet, prey energy density, body mass lost during spawning and lake temperature were measured locally.
• 3 Stocking timing had no effect on return rates to anglers or length or weight of caught fish. Although trout released in autumn were smaller than those released in spring, autumn‐released trout grew at a faster rate and had similar lengths and weights to spring cohorts after 2 years of growth in the lake. Modelled consumption parameters were negatively correlated with trout population size, suggesting that stocking rates (347–809 fish ha^?1 year^?1) caused density‐dependent effects on growth. Although common smelt (Retropinna retropinna) accounted for 85% of total prey consumption, no significant relationship was found between prey consumption by individual trout and adult smelt abundance, possibly because trout are targeting smaller smelt that our abundance estimate did not account for.
• 4 Releasing trout in autumn appears to be advantageous for growth, possibly because (i) temperature is more suitable for growth in autumn–winter than in spring–summer and (ii) prey for small trout is abundant in autumn. Mild winter conditions appear to enhance overwinter survival and growth of rainbow trout in warm‐temperate lakes compared to higher latitudes. This implies that moderately productive warm‐temperate lake ecosystems are highly suitable for trout growth in winter, but less so in summer, when lake stratification and high nutrient levels may create conditions suitable for algal blooms and hypolimnetic deoxygenation. High growth rates of trout in warm‐temperate lakes can therefore be supported by timing releases to coincide with favourable winter conditions.

     

Free-Running Locomotor Activity Rhythms in Cave-Dwelling Catfishes,Trichomycterus sp., from Brazil (Teleostei,Siluriformes)

Locomotor activity of troglobitic (cave restricted) catfishes, Trichomycterus sp., was recorded in the laboratory under constant darkness for ten consecutive days. Infra-red photocell beam crossings were totalled every thirty minutes and stored for later analysis. Spectral analysis of the data followed by a statistical test designed for the detection of significant components was then performed. The results of 14 individuals, seven pigmented and seven albino fishes, are reported here. In eight individuals, four pigmented and four albinos, we were not able to detect significant components in the circadian range, although ultradian and/or infradian significant components were found in all cases. Former studies on other two Brazilian cave catfishes, Pimelodella kronei and Imparfinis sp., showed similar results, suggesting a picture of gradual loss of circadian rhythmicity and persistence of ultradian and infradian rhythms in the locomotor activity of troglobitic populations. The proportion of specimens without significant circadian components was higher in Trichomycterus sp., supposedly less specialized to cave life than the other two species. This is tentatively correlated with a higher environmental stability during the time of evolutionary isolation in the subterranean biotope. These results provide strong arguments for the importance of external selection over circadian rhythmicity.     

Impact of elevated CO2 and increased temperature on Japanese beetle herbivory

To examine how the major elements of global change affect herbivory in agroecosystems, a multifactorial experiment was conducted where soybeans were grown at two levels of carbon dioxide and temperature, including those predicted for 2050, under otherwise normal field conditions. Japanese beetles (Popillia japonica Newman) were enclosed on foliage for 24 h, after which the beetle survivorship, total and per capita leaf consumption, and leaf protease inhibitor activity were measured. The direct effect of temperature on beetle consumption and survivorship also was measured under controlled environmental conditions. No differences in total foliage consumption were observed; however, beetles forced to feed at elevated temperature in the field demonstrated greater per capita consumption and reduced survivorship compared to beetles feeding at ambient temperature. Survivorship was also greater for beetles that consumed foliage grown under elevated CO₂, but there were no interactive effects of CO₂ and temperature, and no differences in leaf chemistry were resolved. Leaf consumption by beetles increased strongly with increasing temperature up to ～37° C, above which increased mortality caused a precipitous decrease in consumption. An empirical model based on the temperature dependence of leaf consumption and flight suggests that the 3.5°C increase in temperature predicted for 2050 will increase the optimal feeding window for the Japanese beetle by 290%. Elevated temperature and CO₂ operating independently have the potential to greatly increase foliage damage to soybean by chewing insects, such as Popillia japonica, potentially affecting crop yields.