Is Harbor Porpoise (Phocoena phocoena) Exhaled Breath Sampling Suitable for Hormonal Assessments?

Over the last decades, exhaled breath sampling has been established for laboratory analysis in various cetacean species. Due to their small size, the usability of respiratory vapor for hormone assessments was questionable in harbor porpoises (Phocoena phocoena). This pilot study compared three different blow collection devices for their suitability in the field and during laboratory processing: a sterile petri dish covered by a Nitex membrane, as well as sterile 50 mL centrifuge tubes with or without manganese(II) chloride as a stabilizer. Collected exhales varied between three, five or ten, depending on feasibility. Hormones were extracted through an ether mix, followed by centrifugal evaporation and cortisol analysis using an immunoassay. Although close to the lower end of the assay's dynamic range, the ELISA produced results (n = 110, 0.102–0.937 ng/mL). Hence, a simple 50 mL centrifuge tube was determined as the best suited blow collection device, while three consecutive exhales proved sufficient to yield results. These findings are promising regarding the suitability of exhaled breath as a matrix for future endocrine and immune system-related studies in harbor porpoises. If further advanced, blow sampling can become an important, non-invasive tool for studying and monitoring health, stress levels and diseases in harbor porpoises.

The Mini Buoy: a novel hydrodynamics sensor for long-term deployments in coastal wetlands

<p>Hydrological monitoring is crucial for management and research in coastal wetlands. However, long-term monitoring is scarce due to the high cost of conventional hydrological equipment. The development of open-source and low-power sensors over the past decade presents an opportunity for enabling long-term, high spatial resolution monitoring of hydrodynamics in the intertidal zone. Here, we present the design, calibration, and application of one such sensor: the Mini Buoy. The Mini Buoy is a battery-powered accelerometer and data logger, contained in a standard centrifuge tube. The Mini Buoy floats upright when inundated, and moves freely about a tether anchored to the substrate. Acceleration is measured along a single axis of the buoy, and motion along the axis is used to measure inundation, currents, and waves. Deployments of up to 6 months are possible, and the buoy can measure current and wave orbital velocities as low as 0.05 m/s. Mini Buoys cost less than €350 to assemble, and the materials are globally available. We present the successful application of Mini Buoys in four contrasting scenarios: (1) characterising waves under calm and stormy conditions; (2) linking saltmarsh erosion-expansion patterns with hydrological exposure; (3) identifying high-resolution spatial variability of waves and currents along a saltmarsh edge; and (4) assessing the suitability of former aquaculture ponds for mangrove restoration. Mini Buoys are also being deployed along mangrove fringes across Vietnam, India, and Bangladesh, in order to detect thresholds in hydrodynamic forcing responsible for triggering erosion or progradation events. Mini Buoys offer an exciting and novel tool for coastal management worldwide.</p>

Genetic Diversity and Emerging Zoonotic Onchocerca Species in Human Populations in Taraba State, Nigeria

Background: A better understanding of parasite population genetic processes in specific biogeography is needed to support onchocerciasis elimination goals. The genetic diversity of Onchocerca microfilariae was explored by amplifying a fragment of the 16S rRNA gene in the endemic area in Taraba State, Nigeria, Methods: Eight (8) communities were selected including six onchocerciasis endemic communities with records of ivermectin treatment having been annually distributed for 10 to 16 years, and two non-onchocerciasis endemic areas. The participants were 211 from endemic and 110 from non-endemic areas as control. Skin snips were taken from consenting participants by convenience sampling methods using a sterile sclera punch, from males and females residing within the communities for ten years and above or since birth, microfilaria and residual skin snips were preserved in RNALater® in a 1.5 ml micro-centrifuge tube. DNA was extracted from microfilariae recovered and from those in residual skin snip specimens. Polymerase Chain Reaction (PCR) amplification using specific primers for 16S genes was done to detect the identity of Onchocerca species. The amplified products were sequenced and analyzed for species identity. Results: Multiple sequence alignment and phylogenetic analysis results showed distinct diversity of two sample sequences (G49_O.v. Gashaka and Y02_O.v. Yorro) from other samples from the study area and other regions, indicating emergence of a new polymorphic strain of O. volvulus. Report of a preliminary case of emerging zoonosis of O. ochengi infection in human (skin snips) sample (O. ochengi G44) in this study. Conclusions: It is clear there is genetic diversity of Onchocerca species and emerging zoonosis in the study site. We suggest further investigation on the extent and potentials of emerging zoonotic onchocerciasis by O. ochengi, in the light of cattle, Simulium vectors, environmental and humans overlap in the study area.

Antistress Effects of San-Huang-Xie-Xin Decoction on Restraint-Stressed Mice Revealed by 1H NMR-Based Metabolomics and Biochemistry Analysis

San-Huang-Xie-Xin decoction (SHXXD), composed of Rhei Radix et Rhizoma, Coptidis Rhizoma, and Scutellariae Radix, is a representative antipyretic and detoxifying prescription in traditional Chinese medicine. In this study, we investigated the antistress effects and underlying mechanisms of San-Huang-Xie-Xin decoction (SHXXD) on restraint-stressed mice by 1H NMR-based metabolomics combined with biochemistry assay. A total of 48 male mice (5 weeks old, 18-22 g) were divided randomly into 6 groups (n=8), including the normal group, restraint-stressed group, vitamin C group (positive drug, 17 mg/kg), and 3-dosage groups of SHXXD (200, 400, and 800 mg/kg). The stress model was induced by restraining mice in a polypropylene centrifuge tube for 6 h every day. The rotarod test was performed, and several biochemical indicators were measured. Moreover, other 24 animals were divided into 3 groups (n=8) including the normal group, restraint-stressed group, and SHXXD group (800 mg/kg) for 1H NMR-based metabolomics analysis. Our results showed that SHXXD significantly increased the rotarod time, thymus index, spleen index, and the levels of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), and interleukin- (IL-) 2, but decreased the levels of malondialdehyde (MDA), IL-1β, tumor necrosis factor- (TNF-) α, corticosterone (CORT), and adrenocorticotropic hormone (ACTH) in restraint-stressed mice. Moreover, the contents of eight endogenous metabolites that were changed by restraint stress were significantly reversed by SHXXD. The results of both metabolomics and biochemical analysis indicated that SHXXD (800 mg/kg, p.o.) could improve the biochemical changes and metabolic disorders in restraint-stressed mice by antioxidation and anti-inflammation, enhancing the body’s immune function and restoring several disturbed metabolic pathways (i.e., lipid metabolism, glycolysis and gluconeogenesis, inflammatory injury, and energy metabolism). Taken together, these results indicated that SHXXD has a potential antistress effect in restraint-stressed mice and could be considered as a candidate drug for stress-related disorders.

Phosphate sorption indices as affected by the calcareousness of soils

An experiment was carried out to study the effects of calcareousness on phosphate sorption indices of soils using three representative calcareous soils, namely Sara (Aquic Eutrochrept), Gopalpur (Aquic Eutrochrept), and Ishurdi (Aeric Haplaquept) series of Bangladesh. Three non-calcareous soils, namely Belabo (Typic dystrudepts), Sonatala (Aeric Endoaquepts) and Ghatail (Aeric Haplaquept) series were also selected for comparison purposes. Phosphate sorption indices of soils were calculated using Langmuir and Freundlich isotherms. Isotherms were constructed taking one gram of air-dried sieved (< 2 mm) soil into a 50 ml centrifuge tube, and subsequently adding seven initial P concentrations, namely 0, 1, 10, 25, 50, 100 and 150 μg/ml to each centrifuge tube employing a soil/solution ratio of 1 : 20 (w/v). According to the Langmuir equation, the amount of phosphate sorbed followed the order: Sonatala > Ghatail > Sara = Gopalpur > Ishurdi > Belabo. The abundance of amorphous iron rather than the calcareousness was putatively responsible for the high phosphate sorption capacity of soils. Maximum phosphorus buffering capacity (MPBC) of the calcareous soils ranged from 33.4 - 62.8 l/kg. Langmuir and Freundlich equations produced different values for soil P requirements (SPR) at 0.2 and 1.0 mg P/l. Calcareous soils would require 27 - 44 mg P/kg soil to attain 0.2 mg P/l soil solution, which is deemed sufficient for crop growth. The soils would require 32 - 58 mg P/kg soil to reach 1.0 mg P/l soil solution, which is regarded to be safe for soils in terms of susceptibility to P losses. The calculated Langmuir constant b values were higher than the threshold value of 0.07 l/mg for two of the calcareous soils. Therefore, even though the non-calcareous soils sorbed more phosphate, higher bonding energy of P sorption for calcareous soils makes them less vulnerable to loss via surface runoff. Dhaka Univ. J. Biol. Sci. 28(1): 93-110, 2019 (January)

A new method for fast extraction and determination of chlorophylls in natural water

Algae collection and chlorophyll extraction are two troublesome steps in the traditional methods used for the determination of chlorophyll concentration in natural water. A new method was established in this study for fast collection and extraction of chlorophyll. Based on our results, the optimum centrifugation condition for collecting algae was determined as: 5000 g for 15 min at 4 °C, and the optimum dilution ratio of dimethyl sulfoxide: 90% acetone was 1:4. The specific steps were as follows: the algae in water samples were collected by centrifugation at 5000 g at 4 °C for 15 min. The precipitated algae were suspended with 2 mL DMSO. Then the sample was transferred to a 15 mL centrifuge tube, and the tube was incubated at 65 °C for 1–2 h in the dark until the sample turned white. After cooling, the chlorophyll extract was diluted with 8 mL 90% acetone, before centrifugation at 5000 g for 5 min. The absorbance values of the supernatants at 750, 664, 647 and 630 nm were used for the calculation of chlorophyll concentrations by the trichromatic equations. This new method saved the filter cost, simplified the extraction process, improved the algae acquisition efficiency, and accelerated the chlorophyll extraction rate.