Human Health Risk Assessment of Naturally Occurring Radioactive Materials in Produced Water—A Case Study

Human health effects from naturally occurring radioactive materials (NORM) in produced water are of concern due to their bioavailability and bioaccumulation characteristics in finfish and shellfish species used for human consumption. Being chemically similar to calcium, radium concentrates mostly in bones, shells, and exoskeletons. Previous studies have been based on the whole-body bioaccumulation of radium in fish where the distribution of radium in bone/exoskeleton and the edible parts of fish were not considered separately and thus the predicted risks were relatively high. In this article, the distribution of radium in the non-edible and edible parts of fish and the probability of exposure to a produced water plume have been studied in order to characterize human health risks. A probabilistic hydrodynamic model has been incorporated in this study. Using the concentration distribution approach, the mean cancer risks to humans were predicted in the range of 8.6 × 10^?7 to 9.5 × 10^?7, which were 2.6 to 2.7 times less than the risks predicted by using the whole body concentrations. The exceedence probability of maximum permissible human health cancer risk of 1 × 10^?4 is close to zero. At a risk level of 1 × 10^?6, the exceedence probability is 21% whereas in the whole body concentration approach it is between 45 to 49%. In this study, no effect on fish from exposure to NORM components in produced water was found.     

Edible bird’s nest supplementation in chilled and cryopreserved Arabian stallion semen

Diluents and various biological products have been used in different animal species, with promising outcomes in post-thaw sperm quality. Nevertheless, only a few reports are available for the semen of Arabian horses. Edible bird’s nest (EBN) – a product of the salivary secretions of swiftlet species is widely known to have both antioxidant and anti-inflammatory properties. Presently, there is no data available on the role of EBN supplemented in different extenders and its effect on semen quality in stallion semen. Two in vitro experiments were conducted to examine the effects of edible bird’s nest (EBN) on the quality of chilled and post-thawed cryopreserved Arabian stallion spermatozoa. In experiment one, 10 ejaculates were collected, divided into two equal parts, diluted using EquiPlus® and INRA 96® and supplemented with 0 % (control), 0.12 %, 0.24 % EBN concentrations. The semen samples were stored at 5 ℃ and observed at 0, 24, and 48 h. Sperm kinetics variables (% total motility [TM] and progressive motility [PM], curvilinear velocity; VCL, straightness; VSL, average path velocity; VAP) were analyzed using computerized assisted sperm analysis. For chilled semen, there was no significant difference in any of the sperm quality parameters between control (0 %), 0.12 %, and 0.24 % EBN supplementation either in INRA96® or EquiPlus®. In experiment two, nine ejaculates were diluted and cryopreserved using EquiPlus Freeze® and INRA Freeze® containing 0 %, 2.4 %, and 4.8 % EBN, and evaluated after thawing. Sperm kinetics, DNA integrity and antioxidant capacity - Biological Anti-oxidant Potential (BAP) and Reactive Oxygen Metabolites (d-ROMs) test were evaluated. In chilled semen, there was no significant difference in any of the sperm quality parameters between control (0 %), 0.12 %, and 0.24 % EBN supplementation either in INRA96® or EquiPlus®. For frozen semen supplemented with 2.4 % and 4.8 % EBN had higher sperm motility parameters compared to control in INRA Freeze® and EquiPlus Freeze®, but the values were not statistically significant (P > 0.05). Also, EBN supplementation had no significant effects on the DNA integrity, biological antioxidant potential, and reactive oxygen metabolites. EBN supplementation had no significant effects on sperm quality and antioxidant status in chilled and frozen Arabian Stallion semen. Future studies might consider different methods of EBN preparation and concentrations to elucidate the potential biological impact of EBN in Arabian stallion semen.     

Pachypodol attenuates Perfluorooctane sulphonate-induced testicular damage by reducing oxidative stress

Perfluorooctane sulfonate (PFOS) is an endocrine disruptor chemical (EDC) with potentially adverse effects on the male reproductive system. Pachypodol (5,4′-dihydroxy-3,7,3′-trimethoxyflavone) is a promising flavonoid isolated from Pogostemon cablin (Blanco) Benth that shows a broad range of pharmacological properties. However, the potential curative effects of pachypodol on testicular toxicity are not available until now. Therefore, this research was proposed to examine the efficiency of pachypodol against PFOS-induced testicular toxicity in adult male rats. The experiments were conducted on Sprague-Dawley rats (n = 48), which were equally distributed into four groups: control, PFOS (20 mg/kg), PFOS + Pachypodol (20 mg/kg + 10 mg/kg respectively), and Pachypodol (10 mg/kg). After 56 days of treatment, testes were excised by slaughtering rats, weighed, and stored till further analysis. The estimated parameters include biochemical markers, spermatogenic indices, hormonal and histopathological profiles. PFOS exposure disturbed the biochemical profile by altering the antioxidant/oxidant balance. For instance, it decreased the activities of catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), and glutathione reductase (GSR) while increasing the concentration of reactive oxygen species (ROS) and level of thiobarbituric acid reactive substances (TBARS). PFOS intoxication also led to a notable decline in viability, motility, epididymal sperm count, and the number of HOS coiled-tail sperms, whereas the higher level of abnormality in the head, mid-piece, and tail of sperms were observed. Besides, it lowered luteinizing hormone (LH), follicle-stimulating hormone (FSH), and plasma testosterone. In addition, PFOS exposure led to histopathological damages in testicles. However, pachypodol treatment potently alleviated all the illustrated impairments in testes. Conclusively, our results demonstrate the promising free-radical scavenging activity of pachypodol, a novel phytochemical, against the PFOS-instigated testicular dysfunctions.     

Extended spectrum beta lactamases-producing Escherichia coli in retail chicken meat from Khyber Pakhtunkhwa,Pakistan

In human diet, poultry meat is an important component due to the presence of vitamins, proteins and minerals. But poultry meat can be contaminated by pathogenic bacteria which are responsible for food borne infections. The current study was therefore aimed at identification of Escherichia coli, a common pathogen causing food borne infections, in chicken samples (n = 400) collected from three districts of KhyberPukhtunkhwa; Peshawar, Kohat and Nowshera. The isolates were identified by Gram staining, API strips and through PCR (Universal Stress Protein). A total of 174 samples were positive for E. coli among the collected chicken samples. The isolates were resistant to TE, NOR and NA while were sensitive to MEM, TZP and FOS. The results were statistically significant having value P ≤ 0.05 in ANOVA. The isolates showed different antibiotic resistance genes; OXA-1, CTX-M15, blaTEM, QnrS, TetA, AAC, AAD, sul1 and sul2 which is the molecular explanations of their antibiotic resistance pattern. The PCR products were sequenced by Next Generation Sequencing (NGS) and the results revealed mutations in AAC gene (M120T and R197T) and CTX-M15 (A85V, N122D, A148S and G247D).To prevent and treat pathogenic diseases, the use of antimicrobial agents in animal husbandry are of utmost concern. The over-use and misuse of antimicrobial agents has made pathogenic E. coli multi drugs resistant making it a causative agent for many diseases in human beings. The results of the current study may be helpful for the physicians the better management of the diseases caused by E. coli.     

Biosorption characteristics of Aspergillus fumigatus for the decolorization of triphenylmethane dye acid violet 49

This study focuses on the possible use of Aspergillus fumigatus to remove acid violet 49 dye (AV49) from aqueous solution. In batch biosorption experiments, the highest biosorption efficiency was achieved at pH 3.0, with biosorbent dosage of 3.0 gL^?1 within about 30 min at 40 °C. The Langmuir and Freundlich models were able to describe the biosorption equilibrium of AV49 onto fungal biomass with maximum dye uptake capacity 136.98 mg g^?1. Biosorption followed a pseudo-second-order kinetic model with high correlation coefficients (R ²?>?0.99), and the biosorption rate constants increased with increasing temperature. Thermodynamic parameters indicated that the biosorption process was favorable, spontaneous, and endothermic in nature, with insignificant entropy changes. Fourier transform infrared spectroscopy strongly supported the presence of several functional groups responsible for dye–biosorbent interaction. Fungal biomass was regenerated with 0.1 M sodium hydroxide and could be reused a number of times without significant loss of biosorption activity. The effective decolorization of AV49 in simulated conditions indicated the potential use of biomass for the removal of color contaminants from wastewater.     

Molecular basis of phenotypic variation in patients with argininemia

Argininemia is an autosomal recessive disorder caused by a deficiency in the liver-type arginase enzyme. Clinical manifestations include progressive spastic diplegia and mental retardation. While the quality of life can severely deteriorate in most such patients, some do show remarkable improvement in neurological symptoms while on controlled diets. We examined the thesis that differences in clinical responses to dietary treatment are based on molecular heterogeneity in mutant arginase alleles. Genomic DNAs from 11 patients with argininemia were examined using the polymerase chain reaction, cloning, and sequencing. Nine mutations representing 21/22 mutant alleles were identified in 11 patients with argininemia, and four of these mutations were expressed in vitro to determine the severity of enzymatic defects. We found that these mutations accounted for 64% of the mutant alleles in our patients. Based on findings in vitro expression tests, the mutations can be considered either severe or moderate. Patients with at least one moderate mutant allele responded well to dietary treatment; concentrations of plasma arginine were controlled within 300 M. In contrast, patients with two severely mutated alleles did not respond to dietary treatment and plasma arginine was over 400 M. Argininemia is heterogeneous at the molecular level. The degree of clinical improvement during dietary treatment is reflected in the concentration of arginine in plasma, as a measure of metabolic control. Plasma arginine levels during treatment is reflected in the concentration of arginine in plasma, as a measure of metabolic control. Plasma arginine levels during treatment correlated with types of molecular defects in the arginase genes.     

Characterization and complementation analysis of sporogenous mutants of Dictyostelium discoideum

Sporogenous mutants of the cellular slime mold Dictyostelium discoideum are defined as mutants which are able to undergo terminal differentiation into spores in monolayer cultures in the presence of millimolar amounts of exogenous cyclic AMP. We describe the morphological development and cellular differentiation of a collection of 12 independently isolated sporogenous mutants of strain V12 M2. All mutants develop more rapidly than do wild-type at an air-water interface, display aberrant morphogenesis, and show overt spore and stalk differentiation as soon as 4 hr after starvation. All mutants differentiate in submerged monolayer culture in the presence of cAMP into variable proportions of spores and stalk cells. A number of the mutants also form both stalk cells and spores in submerged culture in the absence of exogenous cAMP. The spores formed by many of the mutants have a greatly reduced viability. Using parasexual genetics, we have found that two of the 12 mutants analyzed are dominant to wild-type and the remaining ten fall into a minimum of four complementation groups, the overall analysis thus yielding a minimum of four and a maximum of seven complementation groups. Intracellular cAMP levels in vegetative cells are significantly elevated in the two dominant mutants but are similar to wild type in all the other mutants.     

Heterotypic passive protection induced by synthetic peptides corresponding to VP7 and VP4 of bovine rotavirus.

We have evaluated the potential of two peptides derived from highly conserved regions of rotavirus outer capsid proteins (VP7 and VP4) to act as a rotavirus vaccine. The capacity of peptides coupled to rotavirus VP6 spherical particles to provide passive protection in a murine model was compared with the protection induced by peptide-keyhole limpet hemocyanin (KLH) conjugates. Female mice were immunized a total of three times before and during pregnancy. Suckling mouse pups were challenged at 7 days of age with either homologous or heterologous rotavirus serotypes. The efficacy of vaccination was determined by analyzing the clinical symptoms and measuring xylose adsorption in the intestine. In this model the VP4 peptide-VP6 conjugate provided protection equal to that obtained using bovine rotavirus (BRV) as the immunogen. The VP7 peptide-VP6 conjugate provided slightly less protection than the VP4 peptide-VP6 conjugate. A mixture of the VP4 peptide-VP6 and VP7 peptide-VP6 conjugates provided better heterologous protection than immunization with BRV. In contrast, KLH-conjugated peptides provided only partial protection. The significance of a synthetic-peptide-based rotavirus vaccine in the prevention of rotavirus infections is discussed.