Optimization of laccase production by Pycnoporus sanguineus in submerged liquid culture

The white-rot fungus Pycnoporus sanguineus produces laccase under a range of C/N ratios in submerged liquid culture. Enzyme production was increased 50 fold in the presence of 20 μM xylidine to a maximum of 1368 U L-1 in a high carbon low nitrogen medium. Slight repression of enzyme production was observed in high nitrogen culture medium. Other potential inducers were less effective (Tween 80, wood fibres) and reduced the stimulation observed by xylidine alone when included in the same culture medium. Veratryl alcohol failed to stimulate laccase production. Activity of the enzyme activity in crude culture nitrate was stable at temperatures of 35 C and below with a pH optimum of 3.0. The laccase of P. sanguineus was identified as a ca 65 kDa protein produced as multiple isoforms.published_or_final_versio

Prevalence of Intestinal Helminthes among Children in Selected Communities in Monrovia, Liberia

The present study was carried out among children below 15 years in 10 communities in Monrovia. Out of the 646 children recruited in the study, 216 (33.4%) were positive for at least one intestinal helminth parasite. Children between 11 – 15 years had the highest prevalence of intestinal helminthes. Ascaris lumbricoides was the most common intestinal helminth parasite encountered (79.6%), followed by Trichuris trichura (19.0%). Strongyloides stercoralis and Enterobius vermicularis were the least prevalent helminth parasites encountered among the study population (1% each). The population in these communities depended largely on poorly built latrines and buckets for faecal disposal although some (49%) used flush toilets despite their being in poor conditions. Only 23.45 of the 646 children surveyed used pipe borne water for drinking and other domestic purposes. The high prevalence rates of helminth infection obtained could be due to persistent infection and re-infection of the study population as a result of the constant seeding of the soil with parasite eggs and larvae in these communities. Keywords: Prevalence, Intestinal helminth, Children, Liberi

Targeting subchondral bone mesenchymal stem cell activities for intrinsic joint repair in osteoarthritis

Osteoarthritis (OA) is a common age-related disease with complex pathophysiology. It is characterized by wide-ranging tissue damage and ultimate biomechanical failure of the whole joint. However, signs of tissue adaptation and attempted repair responses are evident in OA-affected osteochondral tissues. Highlighted in this review article is the role of bone-resident mesenchymal stem cells (MSCs) in these bone remodeling responses, and a proposal that targeting MSC activities in OA subchondral bone could represent a novel approach for intrinsic joint regeneration in OA. The development of these therapies will require better understanding of MSC proliferation, migration and differentiation patterns in relation to OA tissue damage and further clarification of the molecular signaling events in these MSCs during disease progression

Mercury chemostratigraphy across the Cambrian Series 2 – Series 3 boundary: evidence for increased volcanic activity coincident with extinction?

Flood basalt volcanism represented by the Kalkarindji Province (Australia) is temporally associated with a trilobite mass extinction at the Cambrian Series 2 – Series 3 boundary, providing one of the oldest potential links between volcanism and biotic crisis in the Phanerozoic. However, the relative timing of flood basalt volcanism (Kalkarindji Province, Australia) and the trilobite extinctions, first recorded in North America, is not known. Mercury (Hg) enrichment in the sedimentary record provides a potential proxy for volcanism which may facilitate improved chronologies of eruption and extinction. Here we report mercury records for three sections from mid-shelf strata of the Great Basin (western USA) that straddle the Series 2 – Series 3 boundary. One section (Oak Springs Summit, NV) features a Hg enrichment at the start of the extinction interval, but mercury anomalies are also present at lower levels. These older anomalies may record either earlier phases of Kalkarindji volcanism, eruptions in other locations, or may be the result of sedimentary and/or diagenetic processes affecting the Hg record. In the Carrara Formation at Emigrant Pass, CA, the precise extinction horizon is not well defined, but a carbon isotope anomaly (the Redlichiid-Olenellid Extinction Carbon isotope Event; ROECE) provides a stratigraphic tie point to the Oak Springs Summit section. At Emigrant Pass, Hg enrichments precede the ROECE interval and are absent in the inferred extinction zone. The Pioche Formation at Ruin Wash, NV, lacks Hg enrichment at the extinction horizon but contains older enrichments. The inconsistent Hg records between the three sections demonstrate that factors controlling Hg accumulation and preservation in marine sedimentary environments are not yet fully understood. The effects of redox fluctuations may complicate one-to-one association of sedimentary Hg enrichments and massive volcanism at the Cambrian Series 2 – Series 3 boundary and elsewhere in the geologic record

The fate of steroid estrogens: Partitioning during wastewater treatment and onto river sediments

This is the author's accepted manuscript. The final published article is available from the link below. Copyright @ 2010 Springer Science+Business Media B.V.The partitioning of steroid estrogens in wastewater treatment and receiving waters is likely to influence their discharge to, and persistence in, the environment. This study investigated the partitioning behaviour of steroid estrogens in both laboratory and field studies. Partitioning onto activated sludge from laboratory-scale Husmann units was rapid with equilibrium achieved after 1 h. Sorption isotherms and Kd values decreased in the order 17α-ethinyl estradiol > 17α-estradiol > estrone > estriol without a sorption limit being achieved (1/n >1). Samples from a wastewater treatment works indicated no accumulation of steroid estrogens in solids from primary or secondary biological treatment, however, a range of steroid estrogens were identified in sediment samples from the River Thames. This would indicate that partitioning in the environment may play a role in the long-term fate of estrogens, with an indication that they will be recalcitrant in anaerobic conditions.EPSR

Development and consensus process for a clinical pathway for the assessment and management of chemotherapy-induced peripheral neuropathy

Background: Cancer patients treated with neurotoxic chemotherapy are at risk of developing neurological symptoms that can impact functional capacity and quality of life. However, there are no standardised pathways to assess and manage chemotherapy-induced peripheral neurotoxicity (CIPN). This study aimed to determine consensus on statements regarding a CIPN assessment and management clinical pathway. Methods: A CIPN clinical pathway (CIPN-path) was developed and reviewed by an expert multi-disciplinary panel and consumers. Agreement with 18 statements regarding four content themes (pretreatment review, screening and assessment, management and referral, and CIPN-path feasibility) were assessed by 70 Australian respondents (68 health professionals, 2 consumers), using a 2-stage Delphi survey process to reach consensus. Respondents rated statements using a 5-point Likert scale to determine the level of agreement, with consensus defined as ≥ 80% of respondents agreeing with each statement. Results: The consensus was reached for 14 of 18 items after stage 1 and all items after stage 2. Feedback was obtained for all items to refine the CIPN-path. There was an agreement on important characteristics of the CIPN-path, including pretreatment screening, regular patient-reported assessment, and a stepped-care approach to investigating and managing symptom burden. There was a lack of agreement on who should oversee CIPN assessment, which may differ according to the structure and resources of each site. Conclusions: There was an overall agreement concerning the CIPN-path to assess and manage CIPN, which may be adapted accordingly to the resources of each clinic. The CIPN-path may assist teams across different health services in identifying CIPN symptoms, aiding decision-making, and reducing morbidity from CIPN

PCV13 induced IgG responses in serum associate with serotype-specific IgG in the lung

Pneumococcal conjugate vaccine efficacy is lower for non-invasive pneumonia than invasive disease. In this study, participants were vaccinated with PCV13 or HepA (control). Bronchoalveolar lavage samples were taken between 2-6 months and serum at 4- and 7-weeks post vaccination. In the lung, anti-capsular IgG levels were higher in the PCV13 group compared to control for all serotypes, except 3 and 6B. Systemically, IgG levels were elevated in the PCV group at 4-weeks for all serotypes, except 3. IgG in BAL and serum positively correlated for nearly all serotypes. PCV13 shows poor immunogenicity to serotype 3, implying lack of protective efficacy. Clinical trial registration with ISRCTN: 4534043

Dissociable effects of 5-HT2C receptor antagonism and genetic inactivation on perseverance and learned non-reward in an egocentric spatial reversal task

Cognitive flexibility can be assessed in reversal learning tests, which are sensitive to modulation of 5-HT2C receptor (5-HT2CR) function. Successful performance in these tests depends on at least two dissociable cognitive mechanisms which may separately dissipate associations of previous positive and negative valence. The first is opposed by perseverance and the second by learned non-reward. The current experiments explored the effect of reducing function of the 5-HT2CR on the cognitive mechanisms underlying egocentric reversal learning in the mouse. Experiment 1 used the 5-HT2CR antagonist SB242084 (0.5 mg/kg) in a between-groups serial design and Experiment 2 used 5-HT2CR KO mice in a repeated measures design. Animals initially learned to discriminate between two egocentric turning directions, only one of which was food rewarded (denoted CS+, CS−), in a T- or Y-maze configuration. This was followed by three conditions; (1) Full reversal, where contingencies reversed; (2) Perseverance, where the previous CS+ became CS− and the previous CS− was replaced by a novel CS+; (3) Learned non-reward, where the previous CS− became CS+ and the previous CS+ was replaced by a novel CS-. SB242084 reduced perseverance, observed as a decrease in trials and incorrect responses to criterion, but increased learned non-reward, observed as an increase in trials to criterion. In contrast, 5-HT2CR KO mice showed increased perseverance. 5-HT2CR KO mice also showed retarded egocentric discrimination learning. Neither manipulation of 5-HT2CR function affected performance in the full reversal test. These results are unlikely to be accounted for by increased novelty attraction, as SB242084 failed to affect performance in an unrewarded novelty task. In conclusion, acute 5-HT2CR antagonism and constitutive loss of the 5-HT2CR have opposing effects on perseverance in egocentric reversal learning in mice. It is likely that this difference reflects the broader impact of 5HT2CR loss on the development and maintenance of cognitive function

Optimal measurement of visual motion across spatial and temporal scales

Sensory systems use limited resources to mediate the perception of a great variety of objects and events. Here a normative framework is presented for exploring how the problem of efficient allocation of resources can be solved in visual perception. Starting with a basic property of every measurement, captured by Gabor's uncertainty relation about the location and frequency content of signals, prescriptions are developed for optimal allocation of sensors for reliable perception of visual motion. This study reveals that a large-scale characteristic of human vision (the spatiotemporal contrast sensitivity function) is similar to the optimal prescription, and it suggests that some previously puzzling phenomena of visual sensitivity, adaptation, and perceptual organization have simple principled explanations.Comment: 28 pages, 10 figures, 2 appendices; in press in Favorskaya MN and Jain LC (Eds), Computer Vision in Advanced Control Systems using Conventional and Intelligent Paradigms, Intelligent Systems Reference Library, Springer-Verlag, Berli