Monitoring Rarity: The Critically Endangered Saharan Cheetah as a Flagship Species for a Threatened Ecosystem

Deserts are particularly vulnerable to human impacts and have already suffered a substantial loss of biodiversity. In harsh and variable desert environments, large herbivores typically occur at low densities, and their large carnivore predators occur at even lower densities. The continued survival of large carnivores is key to healthy functioning desert ecosystems, and the ability to gather reliable information on these rare low density species, including presence, abundance and density, is critical to their monitoring and management. Here we test camera trap methodologies as a monitoring tool for an extremely rare wide-ranging large felid, the critically endangered Saharan cheetah (Acinonyx jubatus hecki). Two camera trapping surveys were carried out over 2–3 months across a 2,551km² grid in the Ti-n-hağğen region in the Ahaggar Cultural Park, south central Algeria. A total of 32 records of Saharan cheetah were obtained. We show the behaviour and ecology of the Saharan cheetah is severely constrained by the harsh desert environment, leading them to be more nocturnal, be more wide-ranging, and occur at lower densities relative to cheetah in savannah environments. Density estimates ranged from 0.21–0.55/1,000km², some of the lowest large carnivore densities ever recorded in Africa, and average home range size over 2–3 months was estimated at 1,583km². We use our results to predict that, in order to detect presence of cheetah with p>0.95 a survey effort of at least 1,000 camera trap days is required. Our study identifies the Ahaggar Cultural Park as a key area for the conservation of the Saharan cheetah. The Saharan cheetah meets the requirements for a charismatic flagship species that can be used to “market” the Saharan landscape at a sufficiently large scale to help reverse the historical neglect of threatened Saharan ecosystems.     

Contamination level and human health hazard assessment of heavy metals and polycyclic aromatic hydrocarbons (PAHs) in street dust deposited in Mahshahr,southwest of Iran

Mahshahr has a strategic position and is considered as industrial hub of Iran. Selected heavy metals and polycyclic aromatic hydrocarbons (PAHs) contamination and health risk, and the mineralogical composition of street dust from Mahshahr were investigated. Results indicated that geology is the main determinant of the dust mineralogical composition. Calculated enrichment factor (EF) and principal component analysis (PCA) showed that Pb, Hg, Zn, and Cu accumulations are greatly influenced by anthropogenic sources including traffic and industry. High heavy metals content poses great ecological risk in the study area and exposure doses revealed that ingestion is the main exposure route to street dust, especially for children in residential/commercial areas. It was found that the total amount of PAHs (∑PAHs) varies from 161 to 1996 µg/kg, dominated by four-ring PAHs. Diagnostic ratios and PCA showed that both petrogenic and pyrogenic sources of PAHs in Mahshahr street dust and traffic play important roles in this respect. Furthermore, toxic equivalents and incremental lifetime cancer risk of PAHs in street dust indicated a high potential carcinogenic risk for inhabitants mainly via dermal contact and ingestion pathways particularly for outdoor workers in industrial use scenario. Finally, distribution maps of total hazard index of heavy metals and cancer risk of PAHs indicated the most impacted zones for different groups and use scenarios.     

Expression and Functional Characterization of <Emphasis Type="Italic">Pseudomonas aeruginosa</Emphasis> Recombinant <Emphasis Type="SmallCaps">l</Emphasis>.Asparaginase

Recombinant _l.asparaginase, L.ASNase, from Pseudomonas aeruginosa was purified using nickel affinity chromatography. The affinity purified L.ASNase exhibited a protein band with a molecular weight of 72.4 kDa on a native polyacrylamide gel and 36.276 kDa using SDS–PAGE. The activity of the purified L.ASNase was enhanced by Mg²⁺ and inhibited by Zn²⁺ at a concentration of 5 mM. The specificity of the recombinant L.ASNase towards different substrates was examined, and it was found that the enzyme showed the highest activity towards l.asparagine. Moreover, the enzyme showed lower activity towards other substrates such as _L.glutamine, urea and acrylamide. The in vitro hemolysis assay revealed that the purified L.ASNase did not show hemolysis effect on blood erythrocytes. Serum and trypsin half-life of L.ASNase suggested that the recombinant L.ASNase retained 50% of its initial activity after 90 and 60 min incubation period in serum and trypsin separately.     

Experimentation on Degradation of Petroleum in Contaminated Soils in the Root Zone of Maize (Zea Mays L.) Inoculated with Piriformospora Indica

Plant-based methods such as rhizodegradation are very promising for the remediation of petroleum-contaminated soils. Associations of plants with endophytes can further enhance their phytoremediation potential. In this study, a rhizobox experiment was conducted to investigate whether inoculation with the root-colonizing fungus Piriformospora indica could further enhance the degradation of petroleum hydrocarbons in the root zone of maize (Zea mays L.). The rhizoboxes were subdivided into compartments in accordance with distance from the plants. After filling the boxes with soil from a petroleum-contaminated site, seedlings that had either been inoculated with P. indica or not were grown in the middle compartments of the rhizoboxes and grown for 64 days. A plant-free treatment was included for control. The presence of roots strongly increased the counts of total and petroleum-degrading soil bacteria, respiration, dehydrogenase activity, water-soluble phenols and petroleum degradation. All these effects were also found in the soil adjacent to the middle compartments of the rhizoboxes, but strongly decreased further away from it. Inoculation with P. indica further enhanced all the recorded parameters without changing the spatial pattern of the effects. Inoculated plants also produced around 40% more root and shoot biomass than noninoculated plants and had greener leaves. Together, the results indicate that the treatment effects on the recorded soil microbial and biochemical parameters including petroleum hydrocarbon degradation were primarily due to increased root exudation. Irrespectively of this, they show that maize can be used to accelerate the rhizodegradation of petroleum hydrocarbons in soil and that inoculation with P. indica can substantially enhance the phytoremediation performance of maize.     

On‐Line Control of Glucose Concentration in High‐Yielding Mammalian Cell Cultures Enabled Through Oxygen Transfer Rate Measurements

Glucose control is vital to ensure consistent growth and protein production in mammalian cell cultures. The typical fed‐batch glucose control strategy involving bolus glucose additions based on infrequent off‐line daily samples results in cells experiencing significant glucose concentration fluctuations that can influence product quality and growth. This study proposes an on‐line method to control and manipulate glucose utilizing readily available process measurements. The method generates a correlation between the cumulative oxygen transfer rate and the cumulative glucose consumed. This correlation generates an on‐line prediction of glucose that has been successfully incorporated into a control algorithm manipulating the glucose feed‐rate. This advanced process control (APC) strategy enables the glucose concentration to be maintained at an adjustable set‐point and has been found to significantly reduce the deviation in glucose concentration in comparison to conventional operation. This method has been validated to produce various therapeutic proteins across cell lines with different glucose consumption demands and is successfully demonstrated on micro (15 mL), laboratory (7 L), and pilot (50 L) scale systems. This novel APC strategy is simple to implement and offers the potential to significantly enhance the glucose control strategy for scales spanning micro‐scale systems through to full scale industrial bioreactors.     

Brain uptake of multivalent and multi-specific DVD-Ig proteins after systemic administration

Therapeutic monoclonal antibodies and endogenous IgG antibodies show limited uptake into the central nervous system (CNS) due to the blood-brain barrier (BBB), which regulates and controls the selective and specific transport of both exogenous and endogenous materials to the brain. The use of natural transport mechanisms, such as receptor-mediated transcytosis (RMT), to deliver antibody therapeutics into the brain have been studied in rodents and monkeys. Recent successful examples include monovalent bispecific antibodies and mono- or bivalent fusion proteins; however, these formats do not have the capability to bind to both the CNS target and the BBB transport receptor in a bivalent fashion as a canonical antibody would. Dual-variable-domain immunoglobulin (DVD-Ig) proteins offer a bispecific format where monoclonal antibody-like bivalency to both the BBB receptor and the therapeutic target is preserved, enabling independent engineering of binding affinity, potency, valency, epitope and conformation, essential for successful generation of clinical candidates for CNS applications with desired drug-like properties. Each of these parameters can affect the binding and transcytosis ability mediated by different receptors on the brain endothelium differentially, allowing exploration of diverse properties. Here, we describe generation and characterization of several different DVD-Ig proteins, specific for four different CNS targets, capable of crossing the BBB through transcytosis mediated by the transferrin receptor 1 (TfR1). After systemic administration of each DVD-Ig, we used two independent methods in parallel to observe specific uptake into the brain. An electrochemiluminescent-based sensitive quantitative assay and a semi-quantitative immunohistochemistry technique were used for brain concentration determination and biodistribution/localization in brain, respectively. Significantly enhanced brain uptake and retention was observed for all TfR1 DVD-Ig proteins regardless of the CNS target or the systemic administration route selected.     

Trimethoprim-sulphamethoxazole in Acute Brucellosis

Eight patients with proved brucella infection were treated with trimethoprim-sulphamethoxazole. The dose varied from two to four tablets given twice daily for three weeks. Clinical response was rapid and all patients were asymptomatic and afebrile within two to seven days of starting therapy. Three patients relapsed clinically and bacteriologically within three weeks of ending treatment. There were no side effects of the treatment. It is suggested that the treatment be continued for at least six weeks to prevent relapses.     

Number of Polypeptide Components in Bacteriophage T2L Contractile Sheaths

Isolated purified contractile tail sheaths of bacteriophage T2L were analyzed for their carboxyl terminal amino acids by carboxypeptidase treatment and hydrazinolysis. Glycine and serine were identified as the only two carboxyl end groups. Using corrections for the yields of these two amino acids upon hydrazinolysis, we calculated that there are 154 (+/-30) moles of C-terminal glycine and 130 (+/-45) moles of C-terminal serine per mole of sheath. It appears likely that sheaths contain two types of polypeptide chains in equal numbers, probably 144 of each. The relation of these two components to the mechanism of sheath contraction is discussed.     

Variation in calcification rate of Acropora downingi relative to seasonal changes in environmental conditions in the northeastern Persian Gulf

There is a strong interest in understanding how coral calcification varies with changing environmental conditions, especially given the projected changes in temperature and aragonite saturation due to climate change. This study explores in situ variation in calcification rates of Acropora downingi in the northeastern Persian Gulf relative to seasonal changes in temperature, irradiance and aragonite saturation state (Ω _arag). Calcification rates of A. downingi were highest in the spring and lowest in the winter, and intra-annual variation in calcification rate was significantly related to temperature (r ² = 0.30) and irradiance (r ² = 0.36), but not Ω _arag (r ² = 0.02). Seasonal differences in temperature are obviously confounded by differences in other environmental conditions and vice versa. Therefore, we used published relationships from experimental studies to establish which environmental parameter(s) (temperature, irradiance, and/or Ω _arag) placed greatest constraints on calcification rate (relative to the maximum spring rate) in each season. Variation in calcification rates was largely attributable to seasonal changes in irradiance and temperature (possibly ~57.4 and 39.7% respectively). Therefore, we predict that ocean warming may lead to increased rates of calcification during winter, but decelerate calcification during spring, fall and especially summer, resulting in net deceleration of calcification for A. downingi in the Persian Gulf.

     

Environmental risk assessment of heavy metals pollution in aquatic ecosystem—A case study: Sediment of Kor River,Iran

A comprehensive investigation of fractionation and environmental risk of nine heavy metals is carried out for 12 sediment samples collected from Kor River, Iran. For this purpose, the 5-stage sequential extraction method, along with individual contamination factor, global contamination factor, and Environmental Risk Index (ERI), is used. Total concentrations of Cr, Hg, Ni, and Zn were found to be beyond the threshold effect level. The results of fractionation patterns indicate that As, Cr, Ni, Pb, and Zn are mostly associated with Fe-Mn oxide fraction, organic fraction, and residual fraction, while Cd and Mo are predominantly associated with carbonate fraction. Cu and Hg are mostly associated with organic and exchangeable fractions. The results of ERI revealed High to Dangerous risks in 40% of Kor River stations. The applied approach in this study is beneficial to other environmental studies that require analysis of complex data.