New developments in lentiviral vector design,production and purification

Introduction: Lentiviruses are a very potent class of viral vectors for which there is presently a rapidly growing interest for a number of gene therapy. However, their construction, production and purification need to be performed according to state-of-the-art techniques in order to obtain sufficient quantities of high purity material of any usefulness and safety.

Areas covered: The recent advances in the field of recombinant lentivirus vector design, production and purification will be reviewed with an eye toward its utilization for gene therapy. Such a review should be helpful for the potential user of this technology.

Expert opinion: The principal hurdles toward the use of recombinant lentivirus as a gene therapy vector are the low titer at which it is produced as well as the difficulty to purify it at an acceptable level without degrading it. The recent advances in the bioproduction of this vector suggest these issues are about to be resolved, making the retrovirus gene therapy a mature technology.     

Effects of heat treatment on the antigenicity of four milk proteins in milk protein concentrates

The effects of heat treatment on the antigenicity and potential allergenicity of α-Lactalbumin (α-LA), β-Lactoglobulin (β-LG), α-casein (α-CN), and β-casein (β-CN) in milk protein concentrates (MPCs) were investigated at temperatures in the range of 65–100°C for times from 10 to 30?min. The antigenicity and potential allergenicity of α-LA decreased significantly. The antigenicity of β-LG was sharply increased throughout the heat treatment, while the potential allergenicity decreased significantly only at 85°C and 100°C for 25?min. The antigenicity of α-CN and β-CN showed fluctuated changes, but were all lower than untreated sample. The α-CN potential allergenicity decreased when heated at 65°C and 70°C for 25?min. Compared with untreated sample, the potential allergenicity of β-CN increased sharply after heat treatment. The results showed that different proteins in the MPCs showed different sensitivities under heat treatment.     

Acid-producing capacity from sugars and sugar alcohols among Lactobacillus isolates collected in connection with radiation therapy

ObjectiveTo investigate the acid-producing capacity from sugars and sugar alcohols of oral Lactobacillus collected in connection with radiation therapy (RT) to the head and neck region.DesignLactobacillus were collected from the tongue, buccal mucosa and supragingival plaque in 24 patients before, during, and after RT. The acid-producing capacity of Lactobacillus isolates (n = 211) was analyzed using a colorimetric fermentation test in microtiter plates. Solutions containing 2% sugars (sucrose, glucose, fructose, lactose) or sugar-alcohols (sorbitol and xylitol) were used. After 24 h of incubation, bacterial acid-producing capacity was determined as strong (pH < 5), weak (pH ≥5–≤ 6) or low/absent (pH > 6). Data regarding intake frequency of sugar-rich products and products with sugar-alcohols was collected.ResultsThe highest acid-producing capacity using the sugars was seen for isolates collected during RT. Sorbitol was fermented to a higher extent during and post RT, especially among isolates from plaque. Lactobacillus fermenting xylitol showed the highest acid-producing capacity during RT (p < 0.05). No statistically significant correlations between stimulated whole salivary secretion rate and acid-producing capacity, or between the intake frequency of sugar-rich products or sugar-alcohol containing products and Lactobacillus acid-producing capacity, were found.ConclusionThe results suggest that Lactobacillus isolates, collected from the tongue, buccal mucosa and supragingival plaque, have a higher acid-producing capacity using sugars and sugar-alcohols during RT than one year post RT.     

Role of Aggregatibacter actinomycetemcomitans in glutathione catabolism

Introduction:  Our previous studies demonstrated that three enzymes, γ-glutamyltransferase (GGT), cysteinylglycinase (CGase) and cystalysin, are required for the catabolism of glutathione to produce hydrogen sulfide (H₂S) in Treponema denticola . In this study, we examined glutathione catabolism in Aggregatibacter actinomycetemcomitans .
Methods:  The GGT and CGase of A. actinomycetemcomitans were determined by biological methods and GGT was characterized using a molecular biological approach.
Results:  A. actinomycetemcomitans showed GGT and CGase activity, but could not produce H₂S from glutathione. The addition of recombinant T. denticola cystalysin, an l -cysteine desulfhydrase, to whole cells of A. actinomycetemcomitans resulted in the production of H₂S from glutathione. Subsequently, we cloned A. actinomycetemcomitans GGT gene ( ggt ) and overexpressed the 63 kDa GGT protein. The recombinant A. actinomycetemcomitans GGT was purified and identified. The K _cat/ K _m of the recombinant GGT from N -γ- l -glutamyl-4-nitroaniline as substrate was 31/μ m /min. The activity of GGT was optimum at pH 6.9–7.1 and enhanced by thiol-containing compounds.
Conclusion:  The results demonstrated that A. actinomycetemcomitans had GGT and CGase activities and that the GGT was characterized. The possible role of A. actinomycetemcomitans in glutathione metabolism and H₂S production from oral bacteria was discussed.     

Spontaneous and induced immunoglobulin synthesis and anti-neutrophil cytoplasm antibodies in Wegener's granulomatosis: relation to leukocyte subpopulations in blood and active lesions

Summary Using a reverse plaque forming cell (PFC) assay the production of immunoglobulin (Ig) by peripheral blood mononuclear cells (MNCs) in vitro was studied in 12 patients with Wegener's granulomatosis (WG). Spontaneous IgG production was increased in two of six untreated patients. The IgG response of MNCs from eight untreated patients to pokeweed mitogen (PWM) and Epstein-Barr virus (EBV) stimulation was significantly depressed. The IgM and IgA production followed the individual pattern of IgG. Blood B-cell and T-cell subset concentrations were normal before therapy, whereas the monocyte concentration was increased in four of six patients. Titers of anti-neutrophil cytoplasm autoantibodies (ANCAs) did not correlate with spontaneous or induced Ig production nor with blood leukocyte subset concentrations. Biopsy specimens from upper respiratory tract lesions in seven untreated patients showed numerous macrophages, activated T lymphocytes, and plasma cells, suggesting a pathogenetic role of these cells in the development of lesions and local production of ANCAs.     

Triclosan exhibits a tendency to accumulate in the epididymis and shows sperm toxicity in male sprague‐dawley rats

Triclosan (TCS) is considered a potent endocrine disruptor that causes reproductive toxicity in non‐mammals, but it is still unclear exactly whether TCS has adverse effects on the sperm or reproductive organs in mammals. In this study, we aimed to evaluate the distribution status of TCS in male reproductive organs of rats, and seek the correlation with the TCS‐induced sperm toxicity or reproductive organ damage. Male rats were intragastrically administered with TCS at a dose of 50 mg/kg, the kinetics of TCS in the plasma and reproductive organs were investigated. TCS in testes and prostates both showed a lower‐level distritbution compared to that in the plasma, which indicates it has no tendency to accumulate in those organs. However, TCS in the epididymides showed a longer elimination half‐life (t_1/2z), a longer the mean retention time (MRT), and a lower clearance (CL_Z/F) compared with those in the plasma. Besides, the ratios of mean area under the concentration‐time curve (AUC)_{0–96h(epididymides/plasma)} and AUC_{0–∞(epididymides/plasma)} were 1.13 and 1.51, respectively. These kinetic parameters suggest TCS has an accumulation tendency in the epididymides. Based on this, we investigated the TCS‐induced sperm toxicity and histopathological changes of reproductive organs in rats. TCS was given intragastrically at doses of 10, 50, and 200 mg/kg for 8 weeks. Rats treated with the high dose (200 mg/kg) of TCS showed a significant decrease in daily sperm production (DSP), changes in sperm morphology and epididymal histopathology. Considering the histopathological change in the epididymides, TCS may induce the epididymal damage due to the epididymal accumulation of that. © 2013 Wiley Periodicals, Inc. Environ Toxicol 30: 83–91, 2015.     

‘Outside the Original Remit’: Co‐production in UK mental health research,lessons from the field

The aim of this discursive paper was to explore the development of co‐production and service user involvement in UK university‐based mental health research and to offer practical recommendations for practitioners co‐producing research with service users and survivors, informed by an overview of the key literature on co‐production in mental health and from a critical reflection on applied research through the medium of a case study. The paper is co‐written by a mental health nurse academic and a service user/survivor researcher academic. The authors argue that the implications of co‐production for mental health research remain underexplored, but that both the practitioner and service user/survivor researcher experience and perspective of co‐production in research can provide practical reflections to inform developing research practice. The theories and values of emancipatory research can provide a framework from which both practitioners and service users can work together on a research project, in a way that requires reflection on process and power dynamics. The authors conclude that whilst co‐produced investigations can offer unique opportunities for advancing emancipatory and applied research in mental health, practitioner researchers need to be more radical in their consideration of power in the research process.     

Paths to sustainable wood supply to the pulp and paper industry in Indonesia after diseases have forced a change of species from acacia to eucalypts

In Sumatra and Kalimantan in Indonesia and Sabah in Malaysia, the spread of two diseases, aggravated by damage by fauna, and by the humid tropical environment, has forced a change of planted species from Acacia mangium to Eucalyptus pellita and related interspecific hybrids, at a scale unprecedented in the history of plantation forestry. This experience highlights the risks of relying on any single species for large contiguous plantation estates in environments with endemic biotic and abiotic stresses. There is a need to transition to multiple-species plantation forestry, adopting the opportunities for changeover of species and varieties in short-rotation systems. Industry’s responses for coping with this rapid change have been helped by earlier collaborative research on acacia which promoted management practices that conserved site resources and avoided site degradation during the critical harvesting and inter-rotation phase. The current growth rates of E. pellita and its hybrids are lower than that of A. mangium. Estimates of production from plantations and expanding capacity of the pulp and paper mills highlight a risk of significant shortfalls in wood production. Improving the quality and consistency of forest operations and revision and refocussing of research and development are critical to set and achieve realistic targets for stable, incremental improvements in productivity. Each company should consider investing systematically in contemporary adaptive research for developing and applying integrated management practices that are efficient and feasible on large scales and suitable for their circumstances. There is also a critical need for research to understand the dynamics of local human capital and its relationships with the forestry sector, with focus on improving access to a stable labour force.     

Functional Electrical Stimulation—A New Therapeutic Approach to Enhance Exercise Intensity in Chronic Obstructive Pulmonary Disease Patients: A Randomized,Controlled Crossover Trial

Objective

To evaluate the effect of quadriceps functional electrical stimulation (FES)-cycling on exertional oxygen uptake ($\dot{\text{V}}$o₂) compared with placebo FES-cycling in patients with chronic obstructive pulmonary disease (COPD).