A spatiotemporal model of condition to derive a novel starvation mortality index that improves a state-space stock assessment model for Atlantic cod on the Southern Grand Bank of Newfoundland

Atlantic cod on the Southern Grand Bank (SGB) collapsed in the early 1990’s and a fishing moratorium has been in place since 1994. I investigate how fish condition influences the natural mortality rate (M) and the prospects for rebuilding the SGB cod stock. I developed a body condition model and derived a starvation mortality rate (Mₖ) index. I modelled weight as a function of length, with deviations (i.e., change in condition) for survey strata, year, month, length, and their interactions. The Mₖ index was higher in the spring than in the fall, higher for cod between 55–80 cm in length and for cod larger than 120 cm, and higher during 1991–1993 when the stock experienced a substantial decline. The Mₖ index was incorporated into an age-based state-space stock assessment model (SSAM) as a component of M. This led to a significant decrease (62%) in the size of the cohort process errors (i.e., their standard deviation). This reduction suggests that Mₖ significantly improved the model of stock productivity. Therefore, I conclude that Mₖ explains a substantial portion of the variation in M, and that starvation mortality is an important component of the productivity of SGB cod

Anthelmintic efficacy of albendazole and levamisole against gastrointestinal parasites in sri lanakan elephants at udawalawe, Sri Lanka

альбендазол, левамизол, комплексное лечение, стронгилята, фасциолы, паразитозы, слоны, Шри ЛанкаПроведено сравнение антигельминтной эффективности препаратов «Альбендазол» и «Левомизол» при желудочно-кишечных паразитозах слонов Шри-Ланки. Первый тест проводился с использованием только альбендазола, второй тест – комплексное использование препаратов. Слоны, находящиеся в эксперименте, были инвазированы фасциолами и стронгилятами. Было установлено, что комплексное лечение наиболее эффективно против желудочно-кишечных гельминтов слонов

Bacteria mediated silver nanoparticles: comparison as potent antibiofilm agents

Introduction: Biosynthesized silver nanoparticles (AgNPs) have good antimicrobial properties comparable to chemically synthesized silver nanoparticles. Further, they have good potential as antibiofilm agents.Methods: AgNPs were synthesized from Pseudomonas aeruginosa (ATCC 27853), Escherichia coli (ATCC 25922), Staphylococcus aureus (ATCC 25923) and Acinetobacter baumannii (confirmed clinical isolate) and physically characterized by several techniques. The antibiofilm activity of the AgNPs against biofilms of P. aeruginosa, S. aureus and C. albicans was studied using crystal violet assay. Biofilms were formed in 96-well polystyrene plates and treated with biosynthesized AgNPs for 24 and 48 h.Results: AgNPs synthesized by all bacteria except S. aureus mediated AgNPs displayed 50% biofilm inhibition at AgNP concentrations between 1.98 - 0.225 mg/ml. S. aureus mediated AgNPs showed 50% biofilm inhibition only against S. aureus biofilm. Scanning Electron microscopic images indicated that biosynthesized AgNPs were able to decrease surface coverage of biofilms and to reduce the extracellular matrix causing morphological changes in biofilms noticeably.Conclusion: This study reports the antibiofilm activity of bacteria mediated AgNPs. This is the first report on antibiofilm activity of AgNPs synthesized by Acinetobacter baumannii and also as a comparison of antibiofilm activity of several bacteria mediated AgNPs. According to the results, low dosages of green AgNPs can be applied in treating drug-resistant microbial infections in a cost effective manner. In conclusion, the bacterial synthesized AgNPs have antibiofilm activity and good stability suggesting its usefulness as economic and environmental friendly antibiofilm agents.</p

Neuromorphic liquid marbles with aqueous carbon nanotube cores

Neuromorphic computing devices attempt to emulate features of biological nervous systems through mimicking the properties of synapses, towards implementing the emergent properties of their counterparts, such as learning. Inspired by recent advances in the utilisation of liquid marbles (microlitre quantities of fluid coated in hydrophobic powder) for the creation of unconventional computing devices, we describe the development of liquid marbles with neuromorphic properties through the use of copper coatings and l.0mgml-1 carbon nanotube-containing fluid cores. Experimentation was performed through sandwiching the marbles between two cup-style electrodes and stimulating them with repeated DC pulses at 3.0 V. Our results demonstrate that 'entrainment∗ of a carbon nanotube filled-copper liquid marble via periodic pulses can cause their electrical resistance to rapidly switch between high to low resistance profiles, upon inverting the polarity of stimulation: The reduction in resistance between high and low profiles was approximately 88% after two rounds of entrainment. This effect was found to be reversible through reversion to the original stimulus polarity and was strengthened by repeated experimentation, as evidenced by a mean reduction in time to switching onset of 43%. These effects were not replicated in nanotube solutions not bound inside liquid marbles. Our electrical characterisation also reveals that nanotube-filled liquid marbles exhibit pinched loop hysteresis IV profiles consistent with the description of memristors. We conclude by discussing the applications of this technology to the development of unconventional computing devices and the study of emergent characteristics in biological neural tissue

The genotypes and virulence attributes of C. albicans isolates from oral leukoplakia

There is a debate as to whether some types of oral leucoplakias (OL) are caused by Candida species, and whether they contribute to the malignant transformation, associated with a minority of such lesions. As no detailed population analysis of yeast isolates from OL is available, we evaluated the virulence attributes, and genotypes of 35 C. albicans from OL, and compared their genotypes with 18 oral isolates from healthy individuals. The virulence traits evaluated were esterase, phospholipase, proteinase, haemolysin and coagulase production, and phenotypic switching activity, and yeast adherence and biofilm formation. DNA from OL and control yeasts were evaluated for A, B or C genotype status. Phospholipase, proteinase, and coagulase activity and biofilm formation was observed in 80%, 66%, 97 % and 77 % of the isolates, respectively. Phenotypic switching was detected in 8.6%, while heamolytic, and esterase activity and adherence were noted in all isolates. The genotype A was predominant amongst both the OL and control groups. Due to the small sample size of our study a larger investigation to define the role of candidal virulent attributes in the pathogenicity of OL is warranted, and the current data should serve as a basis until then

Development and validation of a reference marker for identification of aerobic and anaerobic bacteria associated with diabetes chronic wound ulcers using PCR denaturing gradient gel electrophoresis

Introduction: Diabetes chronic wounds consist with a diverse microbial community and unculturablespecies may be highly prevalent.Objectives: This study aimed to establish a bacterial reference marker consisting of a group ofchronic wound related bacteria, using polymerase chain reaction-denaturing gradient gelelectrophoresis (PCR-DGGE) for profiling of bacteria in diabetes chronic wound infections.Methods: DNA was extracted from the known wound bacterial strains. PCR–DGGE was performedusing eubacterial specific primers targeting V2-V3 region of 16S rDNA. DGGE was performed usinga 30-55% denaturing gradient. Migration position of each organism was detected on DGGE gel andimportant organisms were selected. Equal volume from PCR products of each selected organism wasmixed, diluted with gel loading dye in 1:1.5 ratio and used for all DGGE gels. The ladder was thensubjected to species identification of fifteen tissue debridement specimens obtained from diabeteschronic wound ulcers. The identification efficacy was tested by sequencing.Results: DNA of bacterial pathogens which showed different migration distances on the gel werecombined and used as a reference panel. This bacterial ladder consisted of eleven different bacterialspecies including Bacteroides sp., S. aureus, Acineto bacter sp., P. aeruginosa, Streptococcus Group Aand Group B sp., E. faecalis, Providencia sp., Veillonella sp., E .coli and Enterobacter sp. Accordingto the reference panel, Pseudomonas species were abundant. Further the results were confirmed bysequencing.Conclusion: Reference marker allows comparative analysis of DGGE patterns and can be used as atool for presumptive identification of polymicrobial microbiota in chronic wound infections

ADAM19: A Novel Target for Metabolic Syndrome in Humans and Mice

Obesity is one of the most prevalent metabolic diseases in the Western world and correlates directly with insulin resistance, which may ultimately culminate in type 2 diabetes (T2D). We sought to ascertain whether the human metalloproteinase A Disintegrin and Metalloproteinase 19 (ADAM19) correlates with parameters of the metabolic syndrome in humans and mice. To determine the potential novel role of ADAM19 in the metabolic syndrome, we first conducted microarray studies on peripheral blood mononuclear cells from a well-characterised human cohort. Secondly, we examined the expression of ADAM19 in liver and gonadal white adipose tissue using an in vivo diet induced obesity mouse model. Finally, we investigated the effect of neutralising ADAM19 on diet induced weight gain, insulin resistance in vivo, and liver TNF- levels. Significantly, we show that, in humans, ADAM19 strongly correlates with parameters of the metabolic syndrome, particularly BMI, relative fat, HOMA-IR, and triglycerides. Furthermore, we identified that ADAM19 expression was markedly increased in the liver and gonadal white adipose tissue of obese and T2D mice. Excitingly, we demonstrate in our diet induced obesity mouse model that neutralising ADAM19 therapy results in weight loss, improves insulin sensitivity, and reduces liver TNF- levels. Our novel data suggest that ADAM19 is pro-obesogenic and enhances insulin resistance. Therefore, neutralisation of ADAM19 may be a potential therapeutic approach to treat obesity and T2D

Influence of culture medium on in-vitro biofilm formation by Candida species

Objectives: Objective of this study was to establish an in vitro biofilm on the 96 well plates and to determine the efficacy of three different culture media on biofilm formation of Candida albicans and C. tropicalis Methods: A 96 well sterile, polystyrene plate was inoculated using 10^6 cell/ml of C. albicans and C. tropicalis suspensions and the growth rate of planktonic cells was determined by measuring the absorbance (OD492) at 2 hour intervals. Adhesion of Candidial cells to initiate the biofilm formation in the presence of three culture media (Yeast Nitrogen Base (YNB) supplemented with 100 mM glucose, Sabouraud Dextrose Broth (SDB) and RPMI1640) was quantified using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) and Crystal Violet (CV) assay after 90 minutes. Biofilms of C. albicans, C. tropicalis and 1:1 co-biofilms were developed and the growth rates were quantified at 24 hours’ time intervals. Scanning electron microscope (SEM) was performed to assess the architecture. Results: Planktonic cells of both C. albicans and C. tropicalis showed maximum growth with SDB. C. albicans and co-biofilm adhesion were significantly facilitated with RPMI1640 and the best medium for C. tropicalis adhesion was YNB. Biofilms showed the maximum growth rate in RPMI 1640. C. tropicalis exhibited the minimum growth with all three culture media.Conclusions: The maximum growth rate for planktonic C. albicans and C. tropicalis was achieved with SDB. However RPMI 1640 was the best medium for growth of biofilms

Impact of routine laboratory culture media on in-vitro biofilm formation of Pseudomonas aeruginosa, Staphylococcus aureus and Enterococcus faecalis

Objectives: This study was aimed to determine the efficacy of four routine laboratory culture media onbiofilm formation of Pseudomonas aeruginosa, Staphylococcus aureus and Enterococcus feacalis.Methods: A sterile flat bottom 96 well plate was inoculated using 0.5 McFarland equivalent standardcell suspension of P. aeruginosa, S. aureus and E. feacalis and the growth rate of planktonic cells wasquantified by measuring the optical density (OD492) at two hour intervals. Influence of culture mediumon adhesion of bacteria as an initial step of biofilm formation in the presence of four culture media(Nutrient broth (NB), Brain Heart Infusion (BHI) broth, Luria-Bertani (LB) broth and RPMI 1640) wasquantified using MTT (3-[4, 5- dimethylthiazole-2-yl]-2, 5- diphenyltetrazolium bromide) assay after90 minutes adhesion. Biofilms of P. aeruginosa, S. aureus, E. feacalis and their 1:1 mixed biofilmswere developed and the growth was quantified using MTT metabolic activity at 24 hour time intervals.Scanning electron microscopy (SEM) was performed to assess the ultrastructure.Results: On comparing the relative growth of the bacteria in different culture media, the maximumgrowth of all three planktonic cultures was achieved using BHI broth. All mono species and mixedspecies cultures exhibited their maximum adhesion in the presence of RPMI 1640. All biofilm exhibitedthe maximum growth in BHI broth. SEM imaging had shown the enhanced growth of ultrastructure ofthe biofilm with the presence of BHI broth.Conclusions: The maximum planktonic and biofilm growth was achieved with BHI broth. However,bacterial adhesion was enhanced in the presence of RPMI 1640