Mineralogical and geochemical study of carp otoliths from Baiyangdian Lake and Miyun Water Reservoir in China

Carp otoliths from two different freshwaters (Baiyangdian Lake and Miyun Water Reservoir) were mineralogically and chemically analyzed. The water quality standard of Miyun Water Reservoir is Grade 2 which is much better than the Grade 5 of Baiyangdian Lake. The aim of this study was to examine the differences in otoliths in mineralogy and chemistry from the two sites with quite different qualities. All the analyzed carps showed lapillus and sagitta otoliths made of aragonite, except for B-22 (from Baiyangdian Lake) whose lapillus consisted of vaterite and sagitta consisted of aragonite and vaterite; all asteriscus are composed of vaterite. It is inferred that the occurrence of vaterictic otoliths is linked to poor water quality. Chemical analysis showed that significant difference of Pb concentration between sites was tested by t-test of the compare means (t-test comparison: t = 2.043, P<0.05). While the sitespecific differences of the other metals were not significant. In addition, a significant difference of Sn concentration was tested as well (t-test comparison: t = 2.652, P<0.05). Average content of lapilli Pb is consistent with the water dissolved Pb measurement, with higher dissolved Pb concentration in Baiyangdian Lake relative to the Miyun Water Reservoir.Key words: Carp otoliths, water quality, mineralogy, chemistry, Pb

Relationship of phosphorus content in carp otoliths with that in ambient water in Xiaoxi Port of the Taihu Lake, East China

It has been of high concern that the phosphorus pollution is getting serious after lake eutrophication in the Taihu Lake, the third largest freshwater lake in China. As a sensitive  recorder of the ambient water and fish exposures, fish otolith has been studied as a potential dynamic monitor of water quality by many biologists and mineralogists. In order to work out the correlation of phosphorus enrichment in carp otoliths to the ambient water of the carps, the phosphorus concentration in carp otoliths was measured in situ using laser ablation plasma mass spectrometry (LA-ICP-MS) and comparison with the relevant data of the water was conducted. Significant positive correlation was found for phosphorus concentration in carp otoliths to the ambient water in the corresponding time. Therefore, the wild carp otoliths have the potential to act as an environmental indicator of water phosphorus pollution and lake eutrophication.Key words: Carp otoliths, environmental pollution, lake eutrophication, phosphorus enrichment, mineral monitoring, Taihu Lake

The genetic mineralogical characteristics of fish otoliths and their environmental typomorphism

Otolith is a typical biomineral carrier growing on insides of fish skull with prominent zoning structure formed by alternating layers of protein and calcium carbonate around the nucleus. The zoning number and the thickness of the rhythmic zone can reflect the age and the growing velocity. The δ18O values of the calcium carbonate are indicators of the temperature of the water where the fish lives. The geometry, color, common and trace elements, oxygen and carbon isotopes of the zones can be employed effectively to classify the species, trace the source, migration habits, nutrition level of the fish and the variation of the ocean environment, in order to predict the environmental variation trend of related waters and make strategic plan for fishery production. Thermoluminescence technique can be taken as a new tool in the investigation of fish otolith to describe the heavy metal pollution of related waters, and the thermoluminescence parameters can be used to deduce the source and manage fishery resources.Key words: Fish otoliths, age, temperature, species, migration, water environment

KIR and HLA Loci Are Associated with Hepatocellular Carcinoma Development in Patients with Hepatitis B Virus Infection: A Case-Control Study

BACKGROUND: Natural killer (NK) cells activation has been reported to contribute to inflammation and liver injury during hepatitis B virus (HBV) infection both in transgenic mice and in patients. However, the role of NK cells in the process of HBV-associated hepatocellular carcinoma (HCC) development has not been addressed. Killer cell immunoglobulin-like receptors (KIRs) are involved in regulating NK cell activation through recognition of specific human leukocyte antigen (HLA) class I allotypes. METHODOLOGY/PRINCIPAL FINDINGS: To investigate whether KIR and HLA genes could influence the risk of HBV-associated HCC development, 144 HBV-infected patients with HCC and 189 well-matched HBV infectors with chronic hepatitis or cirrhosis as non-HCC controls were enrolled in this study. The presence of 12 loci of KIR was detected individually. HLA-A, -B, -C loci were genotyped with high-resolution. HLA-C group 1 homozygote (OR = 2.02; p = 0.005), HLA-Bw4-80I (OR = 2.67; p = 2.0E-04) and combination of full-length form and 22 bp-deleted form of KIR2DS4 (KIR2DS4/1D) (OR = 1.89; p = 0.017) were found associated with HCC incidence. When the combined effects of these three genetic factors were evaluated, more risk factors were observed correlating with higher odds ratios for HCC incidence (P trend = 7.4E-05). Because all the risk factors we found have been reported to result in high NK cell functional potential by previous studies, our observations suggest that NK cell activation may contribute to HBV-associated HCC development. CONCLUSIONS/SIGNIFICANCE: In conclusion, this study has identified significant associations that suggest an important role for NK cells in HCC incidence in HBV-infected patients. Our study is useful for HCC surveillance and has implications for novel personalized therapy strategy development aiming at HCC prevention in HBV-infected patients

A heterozygous moth genome provides insights into herbivory and detoxification

How an insect evolves to become a successful herbivore is of profound biological and practical importance. Herbivores are often adapted to feed on a specific group of evolutionarily and biochemically related host plants1, but the genetic and molecular bases for adaptation to plant defense compounds remain poorly understood2. We report the first whole-genome sequence of a basal lepidopteran species, Plutella xylostella, which contains 18,071 protein-coding and 1,412 unique genes with an expansion of gene families associated with perception and the detoxification of plant defense compounds. A recent expansion of retrotransposons near detoxification-related genes and a wider system used in the metabolism of plant defense compounds are shown to also be involved in the development of insecticide resistance. This work shows the genetic and molecular bases for the evolutionary success of this worldwide herbivore and offers wider insights into insect adaptation to plant feeding, as well as opening avenues for more sustainable pest management.Minsheng You … Simon W Baxter … et al

Targeted Disruption of Hotair Leads to Homeotic Transformation and Gene Derepression

Long noncoding RNAs (lncRNAs) are thought to be prevalent regulators of gene expression, but the consequences of lncRNA inactivation in vivo are mostly unknown. Here, we show that targeted deletion of mouse Hotair lncRNA leads to derepression of hundreds of genes, resulting in homeotic transformation of the spine and malformation of metacarpal-carpal bones. RNA sequencing and conditional inactivation reveal an ongoing requirement of Hotair to repress HoxD genes and several imprinted loci such as Dlk1-Meg3 and Igf2-H19 without affecting imprinting choice. Hotair binds to both Polycomb repressive complex 2, which methylates histone H3 at lysine 27 (H3K27), and Lsd1 complex, which demethylates histone H3 at lysine 4 (H3K4) in vivo. Hotair inactivation causes H3K4me3 gain and, to a lesser extent, H3K27me3 loss at target genes. These results reveal the function and mechanisms of Hotair lncRNA in enforcing a silent chromatin state at Hox and additional genes