Studies on the occurrence and distribution of heavy metals in sediments in Lagos Lagoon and their effects on benthic microbial population

An investigation was conducted to assess the concentration of heavy metals in sediments in three selected locations along Lagos lagoon comprising University of Lagos, Ebute Metta and Ijora zones and correlate the effect of metal concentrations on benthic microbial population vis a vis the open water bacterial population. Physiochemical analysis revealed a pH of 8.94, 11.98 and 7.82 of University of Lagos, Ebute Metta and Ijora zones respectively. The concentration of lead was more in Ebute Metta zone (Oko Oba) with a value of 22.75 mg/100 g, while the concentration of iron was more in Ijora zone with a value of 45.31 mg/100 g. The concentration of Cadmium was higher than other zones in Ebute Metta with a value of 14.63 mg/100 g. Mercury was more concentrated in University of Lagos zone with a value of 7.83 mg/100 g, while the value for chromium was more in Ebute Metta sediments with a value of 6.81 mg/100 g. Levene’s statistical analysis shows there is no significant difference in the variances for all metals across the three locations understudy. However, ANOVA analysis shows that mean measurements for all metals across the three locations are significantly different at 5% level of significance except for mercury where the mean measurements were not significantly different at 5% level of confidence. The benthic population (bacteria) was less than that of surface water (control).University of Lagos had the highest bacterial mean cfu/ml determined by log10 with a value 6.81 for control and 3.51 for sediments. The cfu value for fungi for control samples for University of Lagos zone, Ebute Metta and Ijora were 1.7, 1.54 and 1.6 respectively. The bacteria isolated and identified were Bacillus subtilis, Bacillus licheniformis, Arthrobacter sp and Achromobacter sp. Fungi isolated were Saccharomyces cerevisiae, Candida utilissima and Sporobolomyces sp. The values for heavy metals for all zones are of public health significance and pose a threat to the survival of both humans and aquatic life. An immediate attention from concerned authorities is required in order to protect the Lagos lagoon and its dependants from further pollution and diseases

A mechanistic model of the regulation of division timing by the circadian clock in cyanobacteria

The cyanobacterium Synechococcus elongatus possesses a circadian clock in the form of a group of proteins whose concentrations and phosphorylation states oscillate with daily periodicity under constant conditions. The circadian clock regulates the cell cycle such that the timing of the cell divisions is biased toward certain times during the circadian period, but the mechanism underlying this phenomenon remains unclear. Here, we propose a mechanism in which a protein limiting for division accumulates at a rate proportional to the cell volume growth and is modulated by the clock. This “modulated rate” model, in which the clock signal is integrated over time to affect division timing, differs fundamentally from the previously proposed “gating” concept, in which the clock is assumed to suppress divisions during a specific time window. We found that although both models can capture the single-cell statistics of division timing in S. elongatus, only the modulated rate model robustly places divisions away from darkness during changes in the environment. Moreover, within the framework of the modulated rate model, existing experiments on S. elongatus are consistent with the simple mechanism that division timing is regulated by the accumulation of a division limiting protein in a phase with genes whose activity peaks at dusk

Plasma transferrin and hemopexin are associated with altered Aβ uptake and cognitive decline in Alzheimer’s disease pathology

Background:Heme and iron homeostasis is perturbed in Alzheimer’s disease (AD); therefore, the aim of the studywas to examine the levels and association of heme with iron-binding plasma proteins in cognitively normal (CN),mild cognitive impairment (MCI), and AD individuals from the Australian Imaging, Biomarker and Lifestyle FlagshipStudy of Ageing (AIBL) and Kerr Anglican Retirement Village Initiative in Ageing Health (KARVIAH) cohorts.Methods:Non-targeted proteomic analysis by high-resolution mass spectrometry was performed to quantify relativeprotein abundances in plasma samples from 144 CN individuals from the AIBL and 94 CN from KARVIAH cohorts and21 MCI and 25 AD from AIBL cohort. ANCOVA models were utilized to assess the differences in plasma proteinsimplicated in heme/iron metabolism, while multiple regression modeling (and partial correlation) was performed toexamine the association between heme and iron proteins, structural neuroimaging, and cognitive measures.Results:Of the plasma proteins implicated in iron and heme metabolism, hemoglobin subunitβ(p= 0.001) was significantlyincreased in AD compared to CN individuals. Multiple regression modeling adjusted for age, sex, APOEε4 genotype, anddisease status in the AIBL cohort revealed lower levels of transferrin but higher levels of hemopexin associated with augmentedbrain amyloid deposition. Meanwhile, transferrin was positively associated with hippocampal volume and MMSE performance,and hemopexin was negatively associated with CDR scores. Partial correlation analysis revealed lack of significant associationsbetween heme/iron proteins in the CN individuals progressing to cognitive impairment.Conclusions:In conclusion, heme and iron dyshomeostasis appears to be a feature of AD. The causal relationship betweenheme/iron metabolism and AD warrants further investigation

Gene diversity in grevillea populations introduced in Brazil and its implication on management of genetic resources.

A variabilidade isoenzimática para seis populações de Grevillea robusta, oriundas de um teste de procedências/progenies, implantado no delineamento em blocos casualizados com 5 plantas por parcela, no Sul do Brasil, é descrita. A estrutura genética da população foi analisada utilizando-se marcadores bioquímicos, aos 5 anos de idade, especificamente para os locos MDH-3, PGM-2, DIA-2, PO-1, PO-2, SOD-1, e SKDH-1. As procedências do norte de ocorrência natural (Rathdowney e Woodenbong) apresentaram divergência genética superior, em relação à média das progênies, considerando o número de alelos por locus, (Ap), a riqueza alélica (Rs), a diversidade genética de Nei (H), e o coeficiente de endogamia (f). A endogamia foi detectada em diversos graus. A testemunha comercial apresentou o maior coeficiente de endogamia, (f = 0,4448), comparativamente à média das procedências (f = 0,2306), possivelmente devido à insuficiente amostragem populacional na região de origem (Austrália). Apesar de sua ocorrência natural restrita, observou-se correlação positiva entre divergência genética e distância geográfica entre as populações originais. A distância genética e análise de cluster, baseada no modelo bayesiano, mostrou três grupos de procedências distintos: 1) Rathdowney- QLD e Woodenbong-QLD; 2) Paddy?s Flat-NSW; e 3) Mann River-NSW, Boyd River-NSW e a testemunha comercial (material utilizado no Brasil). O agrupamento da testemunha com as procedências Mann River-NSW e Boyd River-NSW sugere um maior potencial das procedências do norte para o melhoramento genético visando à produção de madeira no Brasil, devido a sua elevada diversidade genética e baixo coeficiente de endogamia

Behavioural syndrome in a solitary predator is independent of body size and growth rate.

Models explaining behavioural syndromes often focus on state-dependency, linking behavioural variation to individual differences in other phenotypic features. Empirical studies are, however, rare. Here, we tested for a size and growth-dependent stable behavioural syndrome in the juvenile-stages of a solitary apex predator (pike, Esox lucius), shown as repeatable foraging behaviour across risk. Pike swimming activity, latency to prey attack, number of successful and unsuccessful prey attacks was measured during the presence/absence of visual contact with a competitor or predator. Foraging behaviour across risks was considered an appropriate indicator of boldness in this solitary predator where a trade-off between foraging behaviour and threat avoidance has been reported. Support was found for a behavioural syndrome, where the rank order differences in the foraging behaviour between individuals were maintained across time and risk situation. However, individual behaviour was independent of body size and growth in conditions of high food availability, showing no evidence to support the state-dependent personality hypothesis. The importance of a combination of spatial and temporal environmental variation for generating growth differences is highlighted

Programmatic Impact of QuantiFERON-TB Gold In-Tube Implementation on Latent Tuberculosis Diagnosis and Treatment in a Public Health Clinic

Background: QuantiFERON-TB Gold In-Tube (QFT-GIT) is considered an alternative to the tuberculin skin test (TST) for the diagnosis of tuberculosis (TB) infection, but the programmatic impact of QFT-GIT implementation is largely unknown. In March, 2010, the Baltimore City Health Department (BCHD) introduced routine QFT-GIT testing for individuals referred to the TB program for suspected latent TB infection (LTBI). Design: Retrospective study comparing LTBI diagnosis and treatment during the 13 months before and after QFT-GIT implementation at the BCHD TB clinic. Results: 607 and 750 individuals were referred by community-providers for suspected LTBI in the pre- and post-QFT-GIT periods, respectively. Most individuals in the pre- and post-QFT-GIT periods were referred on the basis of a positive TST (597/607 [98%] vs. 690/750 [92%], respectively) and were foreign-born (363/607[59%] vs. 507/750[68%], respectively). BCHD performed QFT-GIT testing for 375/543 (69%) eligible individuals in the post-QFT-GIT period, of which 185 (49%) were positive, 178 (47%) were negative, 1 (0.25%) was indeterminate, and 11 (3%) did not yield results. Concordance of QFT-GIT with TST was low (183/352[52%]). Foreign-born individuals had higher proportions of QFT-GIT positivity (57%) than US-born individuals (36%; AOR 3.3 [95%CI 1.7–6.2]). Significantly fewer individuals received a final diagnosis of LTBI in the post-QFT-GIT period (397/567 [70%]) compared to the pre-QFT-GIT period (445/452 [98%], p,0.001). In the post-QFT-GIT period, onl

Genetic characterization of 12 heterologous microsatellite markers for the giant tropical tree Cariniana legalis (Lecythidaceae)

Twelve microsatellite loci previously developed in the tropical tree Cariniana estrellensis were genetically characterized in Cariniana legalis. Polymorphisms were assessed in 28 C. legalis individuals found between the Pardo and Mogi-Guaçu River basins in the state of São Paulo, Brazil. Of the 12 loci, 10 were polymorphic and exhibited Mendelian inheritance. The allelic richness at each locus ranged from 2-11, with an average of 7 alleles per locus, and the expected heterozygosity ranged from 0.07-0.88. These loci showed a high probability of paternity exclusion. The characteristics of these heterologous microsatellite markers indicate that they are suitable tools for investigating questions concerning population genetics in C. legalis

Allelic frequencies and statistical data obtained from 12 codis STR loci in an admixed population of the Brazilian Amazon

The allelic frequencies of 12 short tandem repeat loci were obtained from a sample of 307 unrelated individuals living in Macapá, a city in the northern Amazon region, Brazil. These loci are the most commonly used in forensics and paternity testing. Based on the allele frequency obtained for the population of Macapá, we estimated an interethnic admixture for the three parental groups (European, Native American and African) of, respectively, 46%, 35% and 19%. Comparing these allele frequencies with those of other Brazilian populations and of the Iberian Peninsula population, no significant distances were observed. The interpopulation genetic distances (FST coefficients) to the present database ranged from FST = 0.0016 between Macapá and Belém to FST = 0.0036 between Macapá and the Iberian Peninsula