The Indigenous Qatari Marine Copepod, Euterpina Acutifrons: A Promising Marine Invertebrate Model Organism for Aquatic Eco-Toxicological Studies

An important objective of aquatic toxicological assessments is to evaluate the effects of water-borne toxic compounds on organisms which play a crucial role in aquatic communities. In marine ecosystems, copepods have a major impact on essential ecological processes: they exert grazing pressure on phytoplankton, and are a significant food source for several fish and macro crustaceans. Euterpina acutifrons, a harpacticoid copepod, is an abundant species in the Arabian Gulf, including the coast of Qatari peninsula. Its high content of poly unsaturated fatty acids make it a nutritionally superior live feed for larval fish in aquaculture, an industry developing fast in Qatar. With its ubiquitous distribution worldwide, inter-and intra-sexual dimorphism, well-defined life cycle, short generation time, and anamorphic developmental stages, this species meets many of the criteria to become a suitable model for toxicity studies. The present study defines protocols for establishing a successful laboratory culture of Euterpina acutifrons and for its acute toxicity testing with four toxicants. This study will add to the refinement of a suite of bioassay techniques being developed at ExxonMobil Research Qatar using a gamut of vertebrate and invertebrate indigenous marine species. A sustainable culture of Euterpina acutifrons was established by rearing ovigerous individuals of this native species isolated from local waters. A few gravid individuals were used to include the natural genetic variability in the population. Through a series of planned trials, a simple protocol was established for culturing and maintaining the species in the laboratory. A temperature of 22 ± 2°C, photoperiod of 12 h light: 12 h darkness, salinity at 40 ± 2 ppt, and a 3:1 microalgal mixture of Chaetoceros sp. (diatom) and Synechococcus sp. (blue-green algae) as food, fed twice every week, was found to give an optimum survival and fecundity in the laboratory. In order to investigate the efficacy of this species as a ecotoxicity test organism, a series of static, acute 24 h and 48 h toxicity tests were performed using three widely used reference toxicants, sodium dodecyl sulfate (SDS, an anionic surfactant used widely in cleaning and hygiene products), 3, 4-dichloroaniline (DCA, a metabolite of several herbicides), and Zinc (heavy metal) at 22 ± 2°C. Impact of chlorine, an anti-biofouling agent used in industrial cooling waters globally, was tested in a semi-static set up, where chlorine dose was renewed at regular intervals. Similar-sized copepodite stages used for these tests were procured through laboratory culture synchronization. The 24 h/48 h LC50 values were calculated based on the end point of the tests, which was mortality or total cessation of mobility. The copepod showed dose-dependent responses and different sensitivity towards the four toxicants; toxicity ranking increasing from DCA, SDS, Zinc to Chlorine. The differences in toxicities can be attributed to different mechanisms of action of the four compounds. The sensitivity of this species compared favorably with other established marine invertebrate models for ecotoxicity testing. Given, the feasibility of culturing, continuous egg production throughout the year, and high reproducibility of the toxicity responses in this study, it is advocated to further explore the use of Euterpina acutifrons as a model organism to assess long- and short-term effects of potential water-borne contaminants in the Arabian Gulf.qscienc

Somatic Mutations Profile of a Young Patient With Metastatic Urothelial Carcinoma Reveals Mutations in Genes Involved in Ion Channels

Background: Urothelial carcinoma is the most common malignancy of the bladder and is primarily considered as a disease of the elderly. Studies that address bladder tumor occurrence in young age groups are rare.Case Presentation: A 19-year-old male presented with a gross total painless hematuria. A histology after biopsy revealed a high-grade transitional cell carcinoma with lymph node metastasis. The patient succumbed to the disease on day 72 of the treatment. Here, we used whole-exome sequencing of a paired tumor-normal sample to identify the somatic mutations and the possible targets of treatment.Result: We predicted eight potential driver mutations (TP53 p.V157L, RB1 c.1498+1G>T, MED23 p.L1127P, CTNND1 p.S713C, NSD1 p.P2212A, MED17 p.G556V, DPYD p.Q814K, and SPEN p.S1078*). In addition, we predicted deleterious mutations in genes involved in the ion channels (CACNA1S p.E1581K, CACNG1 p.P71T, CACNG8 p.G404W, GRIN2B p.A1096T, KCNC1 p.G16V, KCNH4 p.E874K, KCNK9 p.R131S, P2RX7 p.A296D, and SCN8A p.R558H).Conclusions: Most likely, mutations in genes involved in ion channels may be responsible for the aggressive behavior of a tumor. Ion channels are the second largest class of drug targets, and may thus serve as a putative potential therapeutic target in advanced stage urothelial carcinoma

Data from: Enhanced specific loss power of hematite-chitosan nanohybrid synthesized by hydrothermal method

We used a hydrothermal technique for producing hematite (a-Fe2O3) nanoparticles that were then functionalized with chitosan. The prepared iron oxide (a-Fe2O3) nanoparticles were single-phase, according to XRD analysis. The presence of lattice fringes in the HRTEM image confirmed the crystalline nature of the a-Fe2O3. The samples were coated with chitosan and the coating was confirmed by the spectra of Fourier transform infrared (FTIR) analysis. The Mössbauer spectra reveal a mixed relaxation state, which is also supported by the PPMS study. A zero field cooled study revealed the existence of a Morin transition. The hydrodynamic diameter of the coated particles was measured using the dynamic light scattering technique (DLS) to be between 218 and 235 nm, with a polydispersity index ranging from 0.048 to 0.119. The zeta potential was +46.8 mV, which is appropriate for colloidal stability. Both the Vero and HeLa cell lines demonstrated viability incubated for 24 hrs. with the colloids of different concentrations. The maximum temperature, Tmax attained by the hematite-chitosan nanohybrid solution of 0.25 and 4 mg/ml — the lowest and highest concentration, was 42.9 and 48.3ºC, and the specific loss power, SLP was 501.6 and 35.53, which are remarkably high for the Mmax; 300K = 1.98 emu/g.Provided in the Read me.text file for each data

Utilization of Two Microalgae Species, Synechococcus sp. and Cheatoceros sp., for Aquatic Toxicity Assessments in the Qatari Marine Environmen

Microalgal bioassays are currently used worldwide to help assess the impacts of contaminants on aquatic ecosystems. Algae are particularly important to such assessments because they represent the basic trophic level of the aquatic food web and contribute to ecosystem biodiversity. Toxicological impacts to these species may have follow-on effects (e.g., depletion of food source) on higher trophic levels and subsequent biodiversity consequences. ExxonMobil Research Qatar in collaboration with Qatar University Environmental Sciences Center and the Ministry of Environment are currently conducting researchto understand the impact of several water borne contaminantsto species of microalgae found in the Qatari marine environment. The two algal species used in this study included Synechococcus sp. which is a unicellular cyanobacterium that is very widespread in the marine environment and are preferentially found in the upper well–lit surface waters. The other species, Chaetoceros sp. is a centric diatom and is abundantly found in Qatari seawaters. Chaetoceros is a highly diverse diatom genus and has been described as the most dominant phytoplankton group in the ocean, in general. They play an important role in various marine ecosystem as a preferred food source for zooplankton and invertebrate larvae. Two microalgal species were isolated from the Qatari coastal watersand cultured in the laboratory. The cultures were maintained at 22 ± 1.0°C, under a 14 h:10 h/light:dark cycle provided by cool white fluorescence light (7000 ± 10% lux), in nutrient-enriched synthetic seawater (F/2 medium) at pH 8.0 ± 0.5 and salinity 40 g/L. The effect of abiotic factors such as salinity and temperature on the growth of both species was also investigated during culture development. Salinity effects were studied in therange of 25 to 45%. The results show that both species are euryhaline - that is, able to grow at all tested salinities – with best growth achieved at 30 and 40%. Both species were subsequently tested for tolerance to temperature ranging between 16 to 38°C,at both 30 and 40% salinities. These temperature experiments show that the highest growth rate was observed in cultures at 30°C and salinity 30%. Similar results were obtained at 30°C and salinity 40%. The lowest growth rates were observed at the lowest temperatures, while a decreased rate was also observed at the highest temperature. Acute (24 hr) and chronic (72 hr) toxicity tests were carried out on both microalgae species, with copper chloride which is widely used as a reference toxicant. Tests were performed using copper chloride at concentrations ranging between 0.05 and 0.75 mg/l. The test endpoints included: cell division rate inhibition, light-scattering properties of algal species, chlorophyll a fluorescence and esterase activity. Results for Synechococcus sp. and Cheatoceros sp. show a dose-dependent response to contaminant exposure. Consequently, it is apparent that both species may be considered as model test species for use in toxicity assessment and serve as akey component in a battery of toxicity tests with other native Qatari marine organisms. In particular, the toleranceof these microalgae species to fluctuations in salinity and temperature make them an ideal species to further explore the impact of potential effects of toxicants in Qatari waters.qscienc

Community-wise evaluation of rice beer prepared by some ethnic tribes of Tripura

Tripura is inhabited by many indigenous communities having unique ethno-socio-cultural lifestyle with age-old rice beer brewing techniques using wild herbs and local rice varieties popularly known as chuwak or zu. The present study is focused on comparative evaluation of brewing methods and nutritional aspects of rice beer among Debbarma, Jamatia, Koloi, and Molsom tribes of Tripura. Sample ingredients and plant species are properly identified before reporting. Rice beer is also prepared in laboratory conditions for comparative studies of qualitative and quantitative aspects. Thirteen different plant species are used by these four tribes for preparation of starter cultures using soaked rice flour. Markhamia stipulate (Wall.) Seem. is common to all communities for starter cake preparation. Litsea monopetala (Roxb.) Pers. is used by all three communities except Jamatia. The use of Ananus comosus Mill. is common among Debbarma and Jamatia tribes, whereas that of Artocarpus heterophyllus Lam. is common among Molsom and Koloi tribes. However, Aporusa diocia (Roxb.) Muell., Combretum indicum (L.) DeFilipps., and Citrus sinensis (L.) Osbeck. are used only by Debbarma tribe for unique tangy flavor. The physicochemical properties of rice beer varied within tribes for its moisture content, carbohydrate content, reducing sugar, and alcohol percentage. The concentration of alcohol increases with aging and prolonged fermentation. The plants reported here are also reported for having nutritional and medicinal benefits for the metabolic stability in humans, which make the process more prospective for commercialization if a standard for maintaining a quality and associated risk can be determined