Computational fluid dynamics analysis of surgical adjustment of left ventricular assist device implantation to minimise stroke risk

Background. Currently, mechanical support is the most promising alternative to cardiac transplantation. Ventricular assist devices (VADs) were originally used to provide mechanical circulatory support in patients awaiting planned heart transplantation (‘bridge-to-transplantation’ therapy). The success of short-term bridge devices led to clinical trials evaluating the clinical suitability of long-term support (‘destination’ therapy) with left ventricular assist devices (LVADs). The first larger scale, randomised trial that tested long-term support with an LVAD reported a 44% reduction in the risk of stroke or death in patients with an LVAD. In spite of the success of LVADs as bridge-to-transplantation and long-term support, patients managed by these devices are still at risk of several adverse events. The most devastating complication is caused by embolisation of thrombi formed within the LVAD or inside the heart into the brain. Prevention of thrombi formation is attempted through anticoagulation management and by improving LVADs design; however, there is still significant occurrence of thromboembolic events in patients. Investigators have reported that the incidence of thromboembolic cerebral events ranges from 14% to 47% over a period of 6–12 months.

Methods and approach. An alternative method to reduce the incidence of cerebral embolisation is proposed by the co-authors, and the hypothesis is that it is possible to minimise the number of thrombi flowing into the carotid and vertebral arteries by an optimal placement of the LVAD outflow conduit, with or without the addition of aortic bypass connecting the ascending aorta and the innominate artery (IA), or left carotid artery. This paper presents the computational fluid dynamics (CFD) analysis of the aortic arch haemodynamics using a representative geometry of the human aortic arch with or without an alternative aortic bypass. In order to study the trajectory of the thrombi within the aortic arch bed, the CFD code, Fluent 6.3, is utilised to resolve the flow field and to solve the Lagrangian particle tracking of thrombi released randomly at the inlet of the LVAD cannula.

Results. Results are presented for simulations of thrombi in the range of 2–5 mm. The percentage of individual diameter as well as aggregate diameter thrombi flowing to the carotid and vertebral arteries as a function of LVAD conduit placement and aortic bypass implantation is reported. The influence of the LVAD conduit implantation and bypass reveals a nearly 50% variation in predicted cerebral embolism rates.

Conclusions. The adjustment of the location of the anastomosis of the LVAD outflow cannula as well as its angle of incidence plays a significant role in the level of thromboembolisms. By proper adjustment in this CFD study of a synthetic model of an aortic arch bed, we found that nearly a 50% reduction in cerebral embolism could be achieved for a configuration consisting of a shallow angle of implantation over a baseline normal incidence of the LVAD cannula. Within the limitations of our model, we have established that the LVAD implantation geometry is an important factor and should be taken into consideration when implanting an LVAD. It is possible that other parameters such as distance of the LVAD outflow cannula to the root of the IA could affect the thrombi embolisation probabilities. However, the results of this study suggest that the risk of stroke may be significantly reduced by as much as 50% by tailoring the VAD implantation by a simple surgical manoeuvre. The results of this line of research may ultimately lead to techniques that can be used to estimate the optimal LVAD configuration in a patient-specific manner by pre-operative imaging.     

First pollen record for Ancyloscelis apiformes (Apidae: Emphorini) in Central Amazon

Abstract

The first pollen study for the solitary bee Ancyloscelis apiformes (Emphorini) in a nest aggregation in the Central Amazon was made in October 2012 at the Sucupira apiary in east Manaus, Amazonas, at 03° 00? 05″ S, 59° 51? 05″ W. A total of 15 samples/nests (N1–N15) were analysed, including intact pollen loads (stored inside the nest) and post-emergence residues, which were acetolysed and mounted in glycerine gelatin. From each sample, 500 pollen grains were counted to determine the pollen frequencies and diversity (H′) and evenness (J′) indices. The most representative pollen types were Bonamia ferruginea (N1 = 95.6% and N2 = 96.00%) and the Ipomoea (N3 = 96.40%), both of which belong to the Convolvulaceae. In addition, Byrsonima crispa (N10 = 93.40%) and Malpighia glabra (N7 = 90.20% and N9 = 97.60%), representatives of the Malpighiaceae, were classified as temporary specialisation events with frequencies above 90%. In this study, A. apiformes, which is considered an oligolectic bee species, presented a polylectic tendency since it collected large percentages of pollen types from plants in distinct families that were not phylogenetically related.     

Chronotype and energy intake timing in relation to changes in anthropometrics: a 7-year follow-up study in adults

Individuals with a later preference for the daily activities (evening types) tend to have unhealthier behaviors, which could increase their risk for obesity when compared those with an earlier preference (morning types). Furthermore, later food intake timing, another behavior more characteristic of evening types, has been associated with obesity. However, chronotype differences in the long-term weight change and the role of chronotype in the association between energy intake timing and obesity risk are not clear. To study this we first examined the independent associations of chronotype and energy intake timing with anthropometric changes and then whether chronotype modified the association between energy intake timing and obesity risk. Our data included 1097 Finns from DILGOM (DIetary Lifestyle and Genetic Determinants of Obesity and Metabolic syndrome) 2007 (baseline) and 2014 (follow-up) and from Findiet 2007. Chronotype was assessed with a shortened version of Horne and Östberg’s morningness–eveningness questionnaire. Energy intake timing (as percentages of the total energy intake in the morning/evening) was assessed with 48-h dietary recalls. Weight, body mass index (BMI), and waist circumference were based on measured and self-reported values. Analysis of co-variance and multivariable logistic regression models were used for statistical analyses. Evening typed women had greater weight gain (+ 2.3 kg vs. + 0.3 kg, P = 0.016) and increase in BMI (0.7 kg/m² vs. ?0.1 kg/m², P = 0.024) than morning typed women. After excluding participants with depression, these associations attenuated to non-significant. Compared to participants whose energy intake was proportionally lowest during evening, those with proportionally highest energy intake during evening were more likely with obesity (BMI≥ 30 kg/m²) after follow-up (OR 1.97, 95% CI 1.21–3.21, Ptrend = 0.042). Participants’ chronotype did not modify this association (Pinteract = 0.95). In conclusion, our findings indicated that evening energy intake may play a role in obesity regardless of the chronotype. Furthermore, evening typed women were more prone to increases in their anthropometrics, which seem to be at least partly explained by depression. Further studies of this topic are warranted.     

Crystal Structure and Conformation of 5‐Fluorouridine: Conformational Preferences for 5‐Fluorinated Pyranosides

Crystals of 5‐fluorouridine (5FUrd) have unit cell dimensions a = 7.716(1), b = 5.861(2), c = 13.041(1)Å, α = γ = 90°, β = 96.70° (1), space group P2₁, Z = 2, ρ_obs = 1.56 gm/c.c and ρ_calc = 1574 gm/c.c The crystal structure was determined with diffractometric data and refined to a final reliability index of 0.042 for the observed 2205 reflections (I ≥ 3σ). The nucleoside has the anti conformation [χ = 53.1(4)°] with the furanose ring in the favorite C2′–endo conformation. The conformation across the sugar exocyclic bond is g⁺, with values of 49.1(4) and ? 69.3(4)° for Φ_θc and Φ_∞ respectively. The pseudorotational amplitude τ_m is 34.5 (2) with a phase angle of 171.6(4)°. The crystal structure is stabilized by a network of N–H…O and O–H…O involving the N3 of the uracil base and the sugar O3′ and O2′ as donors and the O2 and O4 of the uracil base and O3′ oxygen as acceptors respectively. Fluorine is neither involved in the hydrogen bonding nor in the stacking interactions. Our studies of several 5‐fluorinated nucleosides show the following preferred conformational features: 1) the most favored anti conformation for the nucleoside [χ varies from ? 20 to + 60°] 2) an inverse correlation between the glycosyl bond distance and the χ angle 3) a wide variation of conformations of the sugar ranging froni C2′–endo through C3′–endo to C4′–exo 4) the preferred g⁺ across the exocyclic C4′–C5′ bond and 5) no role for the fluorine atom in the hydrogen bonding or base stacking interactions.     

Diurnal variation in repeated sprint performance cannot be offset when rectal and muscle temperatures are at optimal levels (38.5°C)

The present study investigated whether increasing morning rectal temperatures (T_rec) to evening levels, or increasing morning and evening T_rec to an “optimal” level (38.5°C), resulting in increased muscle temperatures (T_m), would offset diurnal variation in repeated sprint (RS) performance in a causal manner. Twelve trained males underwent five sessions [age (mean ± SD) 21.0 ± 2.3 years, maximal oxygen consumption (V?O₂max) 60.0 ± 4.4 mL.kg^–1 min^–1, height 1.79 ± 0.06 m, body mass 78.2 ± 11.8 kg]. These included control morning (M, 07:30 h) and evening (E, 17:30 h) sessions (5-min warm-up), and three further sessions consisting of a warm-up morning trial (M_E, in 39–40°C water) until T_rec reached evening levels; two “optimal” trials in the morning and evening (M_38.5 and E_38.5, in 39–40°C water) respectively, until T_rec reached 38.5°C. All sessions included 3 × 3-s task-specific warm-up sprints, thereafter 10 × 3-s RS with 30-s recoveries were performed a non-motorised treadmill. T_rec and T_m measurements were taken at the start of the protocol and following the warm-up periods. Values for T_rec and T_m at rest were higher in the evening compared to morning values (0.48°C and 0.69°C, p < 0.0005). RS performance was lower (7.8–8.3%) in the M for distance covered (DC; p = 0.002), average power (AP; p = 0.029) and average velocity (AV; p = 0.002). Increasing T_rec in the morning to evening values or optimal values (38.5°C) did not increase RS performance to evening levels (p = 1.000). However, increasing T_rec in the evening to “optimal” level through a passive warm-up significantly reduced DC (p = 0.008), AP (p < 0.0005) and AV (p = 0.007) to values found in the M condition (6.0–6.9%). Diurnal variation in T_rec and T_m is not wholly accountable for time-of-day oscillations in RS performance on a non-motorised treadmill; the exact mechanism(s) for a causal link between central temperature and human performance are still unclear and require more research.     

Crystal Structure and Conformation of 8-(2-Hydroxyethylamino) and 8-(Pyrrolidin-1-yl) Adenosines

In the course of investigation of 8-alkylamino substituted adenosines, the title compounds were synthesized as potential partial agonists for adenosine receptors. The structure determination of these compounds was carried out with the X-ray crystallography study. Crystals of 8-(2-hydroxyethylamino)adenosine are monoclinic, space group P 2₁; a = 7.0422(2), b = 11.2635(3), c = 8.9215(2) Å, β = 92.261(1)°, V = 707.10(3) ų, Z = 2; R-factor is 0.0339. The nucleoside is characterized by the anti conformation; the ribose ring has the C(2′)-endo conformation and gauche–gauche form across C(4′)–C(5′) bond. The molecular structure is stabilized by intramolecular hydrogen bond of N–H·O type. Crystals of 8-(pyrrolidin-1-yl)adenosine are monoclinic, space group C 2; a = 19.271(1), b = 7.3572(4), c = 11.0465(7) Å, β = 103.254(2)°, V = 1524.4(2) ų, Z = 4; R-factor is 0.0498. In this compound, there is syn conformation of the nucleoside; the ribose has the C(2′)-endo conformation and gauche–gauche form across C(4′)–C(5′) bond. The molecular structure is stabilized by intramolecular hydrogen bond of O–H·N type. For both compounds, the branching net of intermolecular hydrogen bonds occur in the crystal structures.     

Clock gene Bmal1 in mice embryo is dispensable for early embryo development but critical for live birth

In adult animals, the significance of circadian clocks in the regulation of physiology is well established. However, the physiological roles of embryonic clock genes on early embryo development, implantation and perinatal survival are still unclear. In the present study, using genotyping, embryo culture and transfer, the early embryo development, implantation, and perinatal survival of Bmal1+/+, Bmal1+/? and Bmal1?/? embryo were studied. At cleavage stage, the genotype ratio of Bmal1+/+, Bmal1+/? and Bmal1?/? embryo was 1:1.97:0.95, respectively (p > 0.05). Morula or early blastocyst developmental ratio was 83.8 ± 14.3, 87.1 ± 9.2 and 88.7 ± 14.5%, respectively (p > 0.05). After transferring of the three types of embryos to pseudopregnant wild-type mice, the implantation sites 4 days later was 7.7 ± 0.9, 7.2 ± 1.2 and 7.5 ± 0.5 (n = 4, F = 0.265, p = 0.773). Mean litter size of the mice after transferring with the three types of embryos was 5.5, 6.0, and 3.0 (n = 3, F = 30.3, p = 0.001). The development of Bmal1 null embryos was not impaired in preimplantation and early implantation stages, but the litter size had a trend to decrease.     

Association of methylenetetrahydrofolate reductase gene 677C > T polymorphism and Down syndrome

The association between Down syndrome (DS) and maternal polymorphisms in genes encoding folic acid metabolizing enzymes remains a controversial issue. A meta-analysis was performed to evaluate the association of maternal MTHFR 677C > T polymorphism and the risk of having a child with DS. Case–control studies were screened from major literature databases. Twenty articles from 13 countries worldwide, with a total of 2,101 DS and 2,702 control mothers, attended the inclusion criteria. We found a 50 % increase for the association of maternal homozygous TT genotype and DS in both fixed (OR = 1.51; 95 % CI 1.22–1.87) and random effects models (OR 1.54; 95 % 1.15–2.05). Similarly, a significant pooled OR was found for the heterozygote CT, with an OR 1.26; 95 % CI 1.10–1.43 (fixed effects model) and OR 1.28; 95 % 1.08–1.51 (random effects model). As ultra-violet B solar radiation highly depends on latitude, and can promote, in less pigmented skin, intravascular folate photolysis, we stratified the analysis by latitude region, defining as Tropical (between 23.5^° S and 23.5^° N), Sub-Tropical (between 23.5^° and 40^° N and S), and Northern (≥40^o N). Significant association was only found for Sub-Tropical area, both using fixed and random effect models. In conclusion, MTHFR 677C > T polymorphism is a moderate risk factor for DS for some populations, and populations located in Sub-Tropical region seem to be at greater risk. Latitude, ethnicity, skin pigmentation, and red blood cell folate are important variables to be considered in future studies.     

Analysis of Risk Factors of Hemorrhagic Transformation After Acute Ischemic Stroke: Cerebral Microbleeds Do Not Correlate with Hemorrhagic Transformation

To study the potential risk factors including cerebral microbleeds (CMB) of hemorrhagic transformation (HT) after acute ischemic stroke. We included 348 consecutive patients with acute infarction who were hospitalized in two centers from June 2009 to December 2010. Acute ischemic infarctions were subdivided into atherosclerotic, cardioemblic, lacunar, and undetermined infarction groups. The related risk factors were recruited for analysis. All patients underwent gradient-echo T2-weighted imaging (GRE) to detect CMB and HT. Logistic regression analysis was used to analyze relationships, with HT as response variable and potential risk factors as explanatory variables. Multivariate logistic regression analysis demonstrated that predictor factors of HT were cardioembolic infarction (OR 24.956, 95 % CI 2.734–227.801, P = 0.004), infarction of undetermined causes (OR 19.381, 95 % CI 1.834–205.104, P = 0.014), and scores of NIHSS (OR 1.187, 95 % CI 1.109–1.292, P < 0.001), diabetes mellitus (OR 4.973, 95 % CI 2.004–12.338, P = 0.001). Whereas, the level of low-density lipoprotein was the protective factor (OR 0.654, 95 % CI 0.430–0.996, P = 0.048).The prevalence of CMB was 45.98 % (160/348) with no statistically difference among different subtypes. Thirty-five out of 348 (10.06 %) patients with ischemic stroke developed HT with a statistical difference among different subtypes of ischemia (χ ² = 42.140, P < 0.001). The distributions of HI and PH among subgroups were variable with significant differences (χ ² = 17.536, P = 0.001; χ ² = 12.028, P = 0.007). PH frequency of cardioembolism was the highest (4/28, 14.29 %), and symptomatic ICH was also highest (7.14 %). The CMBs do not significantly correlate with HT. Knowledge of the risk factors associated with HT after ACI, especially HT following thrombolyitc therapy may provide insight into the mechanisms underlying the development of HT, helps to develop treatment strategy that reduces the risk of PH and implicates for the design of future acute ischemic stroke trials.     

Thermal mitigation of Pseudomonas aeruginosa biofilms

Bacterial biofilms infect 2–4% of medical devices upon implantation, resulting in multiple surgeries and increased recovery time due to the very great increase in antibiotic resistance in the biofilm phenotype. This work investigates the feasibility of thermal mitigation of biofilms at physiologically accessible temperatures. Pseudomonas aeruginosa biofilms were cultured to high bacterial density (1.7?×?10⁹ CFU cm^?2) and subjected to thermal shocks ranging from 50°C to 80°C for durations of 1–30 min. The decrease in viable bacteria was closely correlated with an Arrhenius temperature dependence and Weibull-style time dependence, demonstrating up to six orders of magnitude reduction in bacterial load. The bacterial load for films with more conventional initial bacterial densities dropped below quantifiable levels, indicating thermal mitigation as a viable approach to biofilm control.     

Diversity of Chemotactic Heterotrophic Bacteria Associated with Arctic Cyanobacteria

The abundance and diversity of chemotactic heterotrophic bacteria associated with Arctic cyanobacteria was determined. The viable numbers ranged between 10⁴ and 10⁶ cell g^?1 cyanobacterial biomass. A total of 112 morphotypes, representing 22 phylotypes based on their 16S rRNA sequence similarity were isolated from the samples. All the phylotypes were Gram-negative with affiliation to the proteobacterial and bacteroidetes divisions. Among the 22 phylotypes, 14 were chemotactic to glucose. Majority of the phylotypes were psychrotolerant showing growth up to 30 °C. Representatives of Alphaproteobacteria, the genus Flavobacterium and the gammaproteobacterial Alcanivorax sp, were psychrophilic with growth at or below 18 °C. A significant percentage of phylotypes were pigmented (~68 %), rich in unsaturated membrane fatty acids and tolerated pH values and NaCl concentrations between 5.0–8.0 and 0.15–1.0 M, respectively. The percentages of phylotypes producing extracellular cold-active enzymes at 4 °C were amylase (18.18 %), lipase and urease (45.45 %), caseinase (59.09 %) and gelatinase (31.8 %).     

Genetic variation in the GCKR gene is associated with non-alcoholic fatty liver disease in Chinese people

Recent genome-wide association studies reported that GCKR rs780094 polymorphism is associated with elevated fasting serum triglyceride levels and elevated levels of C-reactive protein (CRP). There are a ample of data on the association between circulating triglyceride, CRP concentrations and risk of non-alcoholic fatty liver (NAFLD). To determine whether the GCKR rs780094 polymorphism contributes to the development of non-alcoholic fatty liver, a case?Ccontrol study was performed in 903 Chinese subjects. Among study population, 436 patients with B-mode ultrasound-proven NAFLD (318 with steatosis hepatis I°, 90 with steatosis hepatis II° and 28 with steatosis hepatis III°) and 467 controls were genotyped by using TaqMan allelic discrimination assays. We confirmed the association of GCKR rs780094 with NAFLD in Chinese people (OR = 1.607, 95% CI 1.139?C2.271, P _[dom] = 7.2 × 10^?3). In this study, polymorphism in GCKR rs780094 was not significantly associated with the degree of fatty infiltration of the liver. In addition, the T-allele of GCKR rs780094 was significantly associated with increasing fasting triglyceride (P _[add] = 3.8 × 10^?4) and CRP (P _[add] = 2.9 × 10^?4) concentrations after adjusting for age, gender, and BMI. The association with NAFLD remained significant after adjustment for triglyceride, while adjustment for CRP abolished the association. Genetic variation in GCKR gene rs780094 polymorphism contributes to the risk of NAFLD in Chinese people. The effect of genotype on NAFLD is probably mediated through chronic low-grade systemic inflammation rather than through dislipidemia.     

Time-related eating patterns and chronotype are associated with diet quality in pregnant women

Animal studies strongly suggest that timed feeding can have beneficial physiological effects, including protection against the obesogenic and metabolic consequences of a high-fat diet. However, the relationship between variables related to the timing of eating and diet quality in pregnancy women, which is considered as a period of nutritional vulnerability, is still poorly described in the literature. Therefore, the aim of the present study was to investigate the associations between time-related eating patterns and chronotype with diet quality of pregnant women. This cross-sectional study was conducted with 100 pregnant women in the first gestational trimester (≤12 weeks of gestation). The information regarding food intake was obtained by three 24-Hour Dietary Recall (24HR). Time-related eating patterns, i.e., the interval between the first and the last meal (eating duration), nightly fasting, time of the first and last meals, and number of meals eating on a day were determined. Chronotype was derived using the mid-sleep time on free days on weekends, with a further correction for calculated sleep debt. Diet quality was evaluated using the Brazilian Healthy Eating Index-Revised (BHEI-R), validated for the Brazilian population. Linear regression modeling analyses adjusted for confounders were used to investigate the association between time-related eating patterns and chronotype with diet quality. The BHEI-R total score was negatively associated with time of the first meal (β = ?0.355; p = 0.002; r² adjusted = 0.141), and positively associated with eating duration (β = 0.262; p = 0.024; r² adjusted = 0.086) and number of meals (β = 0.273; p = 0.019; r² adjusted = 0.091). In addition, the score of total fruit component was negatively associated with chronotype (β = ?0.236; p = 0.033; r² adjusted = 0.078), time of the first meal (β = ?0.393; p = 0.001; r² adjusted = 0.171), and positively associated with eating duration (β = 0.259; p = 0.022; r² adjusted = 0.087) and number of meals (β = 0.376; p = 0.001; r² adjusted = 0.159). The score for whole fruit component was negatively associated with time of the first meal (β = ?0.388; p = 0.001; r² adjusted = 0.152), and positively associated with number of meals (β = 0.403; p = 0.001; r² adjusted = 0.164). A longer eating duration, earlier time of the first meal, higher number of meals and morningness tendency are associated with a better diet quality in the first gestational trimester – higher scores of the total BHEI-R and/or fruit components. We suggest that nutritional guidelines should consider time-related eating patterns and chronotype to ensure good diet quality of pregnant women since the beginning of gestation, contributing on prevention of metabolic-nutritional complications.     

Computational fluid dynamics simulation to evaluate aortic coarctation gradient with contrast-enhanced CT

Coarctation of aorta (CoA) is a narrowing of the aorta leading to a pressure gradient (ΔP) across the coarctation, increased afterload and reduced peripheral perfusion pressures. Indication to invasive treatment is based on values of maximal (systolic) trans-coarctation ΔP. A computational fluid dynamic (CFD) approach is herein presented for the non-invasive haemodynamic assessment of ΔP across CoA. Patient-specific CFD simulations were created from contrast-enhanced computed tomography (CT) and appropriate flow boundary conditions. Computed ΔP was validated with invasive intravascular trans-CoA pressure measurements. Haemodynamic indices, including pressure loss coefficient (PLc), time-averaged wall shear stress (TAWSS) and oscillatory shear index (OSI), were also quantified. CFD-estimated ΔP values were comparable to the invasive ones. Moreover, the aorta proximal to CoA was exposed to altered TAWSS and OSI suggesting hypertension. PLc was found as a further geometric marker of CoA severity. Finally, CFD-estimated ΔP confirmed a significant reduction after percutaneous balloon dilatation and stenting of the CoA in one patient (e.g. from ΔP～52 mmHg to ΔP～3 mmHg). The validation of the ΔP computations with catheterisation measurements suggests that CFD simulation, based on CT-derived anatomical data, is a useful tool to readily quantify CoA severity.     

Genetic polymorphims of estrogen receptor alpha −397 PvuII (T>C) and −351 XbaI (A>G) in a portuguese population: prevalence and relation with breast cancer susceptibility

Estrogen receptor alpha (ERα), that mediates the biologic effects of estrogen in estrogen-sensitive tissues like breast, is genetically polymorphic. To evaluate the association between ?397 PvuII (T>C) and ?351 XbaI (A>G) restriction fragment length polymorphisms (RFLPs) in intron 1 of ERα gene and susceptibility of breast cancer, we undertook a case–control study in BRCA1 185delAG and 5382insC/BRCA2 6174delT negative Portuguese women. The study population consisted of 107 patients with histological diagnosis of breast cancer and 121 women with no history of breast cancer. Genomic DNA was extracted from blood samples and genotyping analyses were performed by PCR–RFLP. XbaI polymorphism was associated with a significant reduced risk of breast cancer for carriers of the x allele in homozygozity (OR 0.178; 95 % CI 0.070–0.456; P < 0.001) or heterozigozity (OR 0.223; 95 % CI 0.089–0.561; P = 0.001). The PvuII polymorphism was associated with a non-significantly reduced risk. The combined analysis of PvuII and XbaI polymorphisms revealed none synergistic effect of the two genotypes, except for simultaneous carriers of pp and xx genotypes, that have a reduced risk of breast cancer (OR 0.226; 95 % CI 0.049–1.035; P = 0.044). The combination of PvuII and XbaI genotypes into haplotypes showed that carriers of two copies of the px (ppxx) haplotype had a reduced risk of breast cancer (OR 0.405; 95 % CI 0.194–0.843; P = 0.014), compared with PX (PPXX + PPXx + PpXX + PpXx) haplotypes. PvuII and XbaI polymorphisms were in linkage disequilibrium both in cases (D = 0.044, r² = 0.049, X² = 5.216, P = 0.022) and controls (D = 0.090, r² = 0.139, X² = 16.819, P < 0.001), but not in the entire sample population analyzed as a whole (D = 0.087, r² = 0.0076, X² = 1.733, P = 0.188). In conclusion, in this case–control study we found that ERα gene XbaI polymorphism may modify individual susceptibility for breast cancer in this population.     

Chronotype,social jetlag,and time perspective

ABSTRACT

The phase of entrainment (chronotype) is known to be associated with time perspective (TP), suggesting that the state of circadian system is involved in the long-term planning of human life. However, little is known regarding the influence of circadian misalignment on long-term planning ability. The aim of this study was to investigate the association between social jetlag (SJL) and TP. A total of 1064 schoolchildren and university students (mean age ± standard deviation, 19.2 ± 2.9 years; range, 15–25 years; females, 71.7%) from four cities in the Russian Federation located between 56.9 and 61.7 degrees North completed the Munich ChronoType Questionnaire, the Pittsburgh Sleep Quality Index, the Seasonal Pattern Assessment Questionnaire, and Zimbardo Time Perspective Inventory. Study participants also indicated personal data (age, sex, height weight, place of residence, and achievements). A multiple regression analysis with stepwise inclusion of predictors in the model was performed to evaluate associations between time perspective characteristics (dependent variables) and predictor variables. The change in R² was used as the measure of effect size. Chronotype was found to be a moderate predictor of future TP (B = 0.034; ΔR² = 0.037). In addition, sleep quality was found to be a moderate predictor of past negative (B = 0.043; ΔR² = 0.074), present fatalistic (B = 0.021; ΔR² = 0.035), and deviation from balanced TP (B = 0.034; ΔR² = 0.066). Mood seasonality was a moderate predictor of present hedonistic TP (B = 0.016; ΔR² = 0.038), and social jetlag was a weak predictor of present fatalistic (B = 0.052; ΔR² = 0.019), future (B = ?0.033; ΔR² = 0.004), and deviation from balanced TP (B = 0.047; ΔR² = 0.012). In conclusion, this study found a weak but significant association between social jetlag and TP in adolescents and young adults.     

Reproduction efficiency of the Horse Leech,Haemopis sanguisuga (Linnaeus, 1758)

The aquaculture sector has recently focused on alternative food sources due to increased costs and limited resources. Live food sources, such as invertebrates, have important roles in digestion processes of fish. It was aimed to determine the reproduction efficiency of the horse leech, Haemopis sanguisuga, which is expected to be used as an alternative live nutritional source in aquaculture in this study. The study was conducted at ambient temperature in the laboratory conditions for three months. A total of 25 gravid leeches with an average body mass of 6.91 ± 2.20 g were used. The leeches lost up to 75% of their body mass and laid 4.30 ± 1.49 cocoons at 12.0 ± 8.2 days interval during cocoon laying period. Leeches stopped laying cocoon when the temperature fell to 16 °C. The average of offspring hatched from the cocoons was 6.45 ± 2.86. The length–body mass relationship of the offspring was exponential (W = 0.012L^2.809, R² = 0.898). The results from the current study indicate that the basic biological parameter affecting the reproduction efficiency of H. sanguisuga is the size of the broodstock leeches, and reproduction activity weakens the broodstocks.     

Accuracy of the use of energy conversion factors for compound fish diets

Conversion factors of 23.6, 39.5 and 17.2 MJ/kg for protein, lipid and carbohydrate contents, respectively, are frequently used in fish studies to calculate the gross energy (GE) content of compound diets. Values predicted according to the above resulted in linear relationships of observed GE values with similar R ² and mean prediction error (MPE) values when using either nitrogen-free extract (NFE) (R ² = 0.5713, RMSE = 1.3134, MPE = 0.0741, n = 129, 32 studies) or starch (R ² = 0.5665, RMSE = 1.6768, MPE = 0.0839, n = 190, 45 studies) as measurements of carbohydrate content. Apparent digestible carbohydrate content (either NFE or starch) was found to be linearly-related (R ² values of 0.7531 and 0.7460, respectively) to its dietary content in compound fish diets. Predicted apparent digestible protein (ADP), lipid (DL) and carbohydrate contents, together with energy conversion factors, presented R ² and MPE values of 0.6205 (RMSE = 1.2606) and 0.2051, respectively, between observed and predicted apparent digestible energy (ADE) content with NFE as measurement of carbohydrate content (n = 97, 17 studies, eight fish species). However, with carbohydrates quantified by starch content, an R ² value of 0.7017 (RMSE = 1.7556) and MPE of 0.1055 were obtained (n = 37, 10 studies, five fish species).     

Degradation and Detoxification of Nicosulfuron by a Pseudomonas Strain Isolated from a Contaminated Cornfield Soil

ABSTRACT

The dissipation and detoxification of nicosulfuron (NS) by Pseudomonas aeruginosa B9 isolated from a cornfield soil was investigated. The fastest decline of NS occurred at 40 µg ml^?1 in liquid media with 0.25% glucose plus 0.05% yeast extract (DT₅₀ = 4 days) with a notable pH reduction (pH ? 5). Bioassay tests showed considerable phytotoxicity of NS for Cress (Lepidium sativum L.) with 50% shoot growth inhibition (SGI) at 40 µg ml^?1. The dissipation of NS (40 µg ml^?1) by the B9 isolate reduced the SGI significantly (SGI: up to 45 ± 3%) compared to the non-inoculated media (SGI: up to 58 ± 4%). In soils with the B9 isolate, NS dissipation, especially at 0.3 µg g^?1, was faster with a more significant SGI reduction (k = 0.08 ± 0.00 day^?1; SGI = 2 ± 1%) compared to non-inoculated samples (k = 0.03 ± 0.00 day^?1; SGI = 8 ± 1%). NS initially inhibited soil respiration, microbial biomass carbon, and dehydrogenase activity. The effect was however transient, and these parameters recovered within 10 days, especially in the presence of the isolate. Overall, this study proves Pseudomonas aeruginosa B9 as a suitable candidate for bioremediation of NS in contaminated sites.     

Evaluation of DNA,BSA binding,and antimicrobial activity of new synthesized neodymium complex containing 29-dimethyl 110-phenanthroline

In order to evaluate biological potential of a novel synthesized complex [Nd(dmp)₂Cl₃.OH₂] where dmp is 29-dimethyl 110-phenanthroline, the DNA-binding, cleavage, BSA binding, and antimicrobial activity properties of the complex are investigated by multispectroscopic techniques study in physiological buffer (pH 7.2).The intrinsic binding constant (K_b) for interaction of Nd(III) complex and FS–DNA is calculated by UV–Vis (K_b = 2.7 ± 0.07 × 10⁵) and fluorescence spectroscopy (K_b = 1.13 ± 0.03 × 10⁵). The Stern–Volmer constant (K_SV), thermodynamic parameters including free energy change (ΔG°), enthalpy change (?H°), and entropy change (?S°), are calculated by fluorescent data and Vant’ Hoff equation. The experimental results show that the complex can bind to FS–DNA and the major binding mode is groove binding. Meanwhile, the interaction of Nd(III) complex with protein, bovine serum albumin (BSA), has also been studied by using absorption and emission spectroscopic tools. The experimental results show that the complex exhibits good binding propensity to BSA. The positive ΔH° and ?S° values indicate that the hydrophobic interaction is main force in the binding of the Nd(III) complex to BSA, and the complex can quench the intrinsic fluorescence of BSA remarkably through a static quenching process. Also, DNA cleavage was investigated by agarose gel electrophoresis that according to the results cleavage of DNA increased with increasing of concentration of the complex. Antimicrobial screening test gives good results in the presence of Nd(III) complex system.