Simple enrichment system for hydrogen producers

This study presents a simple enrichment system where gas pressure produced by microbes performs functions that are normally done by labor. The system was tested with Escherichia coli strains with different hydrogen production and growth capabilities. The results show that the system can enrich the best hydrogen producer.     

Cruciate Ligament Reconstruction and Risk of Knee Osteoarthritis: The Association between Cruciate Ligament Injury and Post-Traumatic Osteoarthritis. A Population Based Nationwide Study in Sweden, 1987–2009

Objective

To study the association between Cruciate Ligament (CL) injury and development of post-traumatic osteoarthritis in the knee in patients treated operatively with CL reconstruction compared with patients treated non-operatively.

Design

Population based cohort study; level of evidence II-2.

Setting

Sweden, 1987–2009.

Participants

All patients aged between 15–60 years being diagnosed and registered with a CL injury in The National Swedish Patient Register between 1987 and 2009.

Main Outcome Measures

Knee osteoarthritis.

Results

A total of 64,614 patients diagnosed with CL injury during 1987 to 2009 in Sweden were included in the study. Seven percent of the patients were diagnosed with knee OA in specialized healthcare during the follow-up (mean 9 years). Stratified analysis by follow-up showed that while those with shorter follow-up had a non-significant difference in risk (0.99, 95%CI 0.90–1.09 for follow-up less than five years compared with the non-operated cohort), those with longer follow-up had an increased risk of knee OA after CL reconstruction (HR = 1.42, 95%CI 1.27–1.58 for follow-up more than ten years compared with non-operated cohort). The risk to develop OA was not affected by sex.

Conclusion

CL reconstructive surgery does not seem to have a protective effect on long term OA in either men or women.     

Advantages of Papio anubis for preclinical testing of immunotoxicity of candidate therapeutic antagonist antibodies targeting CD28

Antagonist anti-CD28 antibodies prevent T-cell costimulation and are functionally different from CTLA4Ig since they cannot block CTLA-4 and PDL-1 co-inhibitory signals. They demonstrated preclinical efficacy in suppressing effector T cells while enhancing immunoregulatory mechanisms. Because a severe cytokine release syndrome was observed during the Phase 1 study with the superagonist anti-CD28 TGN1412, development of other anti-CD28 antibodies requires careful preclinical evaluation to exclude any potential immunotoxicity side-effects. The failure to identify immunological toxicity of TGN1412 using macaques led us to investigate more relevant preclinical models. We report here that contrary to macaques, and like in man, all baboon CD4-positive T lymphocytes express CD28 in their effector memory cells compartment, a lymphocyte subtype that is the most prone to releasing cytokines after reactivation. Baboon lymphocytes are able to release pro-inflammatory cytokines in vitro in response to agonist or superagonist anti-CD28 antibodies. Furthermore, we compared the reactivity of human and baboon lymphocytes after transfer into non obese diabetic/severe combined immunodeficiency (NOD/SCID) interleukin-2rγ knockout mice and confirmed that both cell types could release inflammatory cytokines in situ after injection of agonistic anti-CD28 antibodies. In contrast, FR104, a monovalent antagonistic anti-CD28 antibody, did not elicit T cell activation in these assays, even in the presence of anti-drug antibodies. Infusion to baboons also resulted in an absence of cytokine release. In conclusion, the baboon represents a suitable species for preclinical immunotoxicity evaluation of anti-CD28 antibodies because their effector memory T cells do express CD28 and because cytokine release can be assessed in vitro and trans vivo.     

Drug-induced resistance evolution necessitates less aggressive treatment

Increasing body of experimental evidence suggests that anticancer and antimicrobial therapies may themselves promote the acquisition of drug resistance by increasing mutability. The successful control of evolving populations requires that such biological costs of control are identified, quantified and included to the evolutionarily informed treatment protocol. Here we identify, characterise and exploit a trade-off between decreasing the target population size and generating a surplus of treatment-induced rescue mutations. We show that the probability of cure is maximized at an intermediate dosage, below the drug concentration yielding maximal population decay, suggesting that treatment outcomes may in some cases be substantially improved by less aggressive treatment strategies. We also provide a general analytical relationship that implicitly links growth rate, pharmacodynamics and dose-dependent mutation rate to an optimal control law. Our results highlight the important, but often neglected, role of fundamental eco-evolutionary costs of control. These costs can often lead to situations, where decreasing the cumulative drug dosage may be preferable even when the objective of the treatment is elimination, and not containment. Taken together, our results thus add to the ongoing criticism of the standard practice of administering aggressive, high-dose therapies and motivate further experimental and clinical investigation of the mutagenicity and other hidden collateral costs of therapies.     

A Second-order Dynamic Model for the Frost Hardiness of Trees

The development of frost hardiness in forest trees is describedby a dynamic model in which the input variables are the prevailingenvironmental conditions and the developmental stage of trees.The assumption of the model is that for each temperature andphotoperiod there is a discrete stationary level of frost hardiness,which is attained if these environmental factors remain constant.The dependence of the stationary level on temperature and photoperiodis assumed to be piece-wise linear and additive. The rate ofacclimation, i.e. frost hardening or dehardening, is describedas a second-order dynamic process with two time constants, thesecond of which changes depending on the stage of the annualdevelopment of the trees. The frost hardiness model was calibratedand tested using experimental data from Douglas fir [Pseudotsugamenziesii var. glauca (Beissn.) Franco] seedlings. The resultssuggest that the second-order model describes the changes infrost hardiness better than the first-order model with onlyone time constant.Copyright 1995, 1999 Academic Press Acclimation, developmental stage, Douglas fir, dynamic model, frost hardiness, photoperiod, Pseudotsuga menziesii, temperature     

Assessing product environmental performance with PEF methodology: reliability,comparability, and cost concerns

Purpose

The Product Environmental Footprint (PEF) method was launched by the European Commission to harmonize the measurement of the product’s environmental performance. The PEF aims to increase the supply of green products in EU markets by lowering the cost of measuring the product’s environmental performance, enabling reliable environmental claims, and conducting proper product comparison. This study assesses whether the methodological choices of PEF enable reliable and comparable PEF studies to be conducted in a cost-efficient way.

Methods

The PEF was compared with ISO 14044, ISO/TS 14067, and the Greenhouse Gas Protocol Product Standard to identify the differences in the methodological choices. From a practical perspective, the possible challenges for PEF that could not be identified by a method comparison were obtained via interviews. The interviewees were company representatives participating in a 3-year PEF pilot phase to create Product Environmental Footprint Category Rules (PEFCR). To discover the possible advantages and disadvantages of the PEF, the methodological choices for PEF itself were assessed from the standpoints of reliability, comparability, and cost. In conclusion, some proposals for improvements have been suggested.

Results and discussion

The impact assessment phase, i.e., some of the predefined impact assessment methods, together with a selected normalization method include disadvantages as regards reliability and comparability. They are not sufficiently mature to properly reflect both the product studied and its potential environmental impact. From a cost perspective, the inventory analysis phase increases the workload due to the cutoff ban, the numerous predefined impact assessment categories, and the data quality assessment of all data. However, the predefined issues, e.g., requirements for data quality to be determined in PEFCRs, could also increase the comparability and lower the costs of the PEF study, since these need not be determined separately for each study. Additionally, the reliability maybe increased due to the data quality assessment of all data.

Conclusions

Currently, in the PEFs 3-year pilot phase, both advantages and disadvantages exist as regards reliability, costs, and comparability. Since PEF aims are important, the Commission and PEFCR developers should devote time to finding the most appropriate methodological choices and continue developing the method further. It is important to find a balance between comparability, reliability, and costs. Additionally, the current issues and characteristics of EU green products market should be taken into account when implementing PEF.

     

Impact of Monochorionicity and Twin to Twin Transfusion Syndrome on Prenatal Attachment,Post Traumatic Stress Disorder,Anxiety and Depressive Symptoms

Monochronioric (MC) twin pregnancies are considered as high-risk pregnancies with potential complications requiring in-utero interventions. We aimed to assess prenatal attachment, anxiety, post-traumatic stress disorder (PTSD) and depressive symptoms in MC pregnancies complicated with Twin-To-Twin-transfusion syndrome (TTTS) in comparison to uncomplicated monochorionic (UMC) and dichorionic pregnancies (DC). Auto-questionnaires were filled out at diagnosis of TTTS and at successive milestones. Prenatal attachment, PTSD, anxiety and perinatal depression were evaluated respectively by the Prenatal Attachment Inventory (PAI) completed for each twin, the Post-traumatic Checklist Scale (PCLS), the State-Trait Anxiety Inventory (STAI) and the Edinburgh Perinatal Depression Scale (EPDS). There was no significant difference in the PAI scores between the two twins. In the DC and UMC groups, PAI scores increased throughout pregnancy, whilst it didn’t for TTTS group. TTTS and DC had a similar prenatal attachment while MC mothers expressed a significantly higher attachment to their fetuses and expressed it earlier. At the announcement of TTTS, 72% of the patients present a score over the threshold at the EPDS Scale, with a higher score for TTTS than for DC (p = 0.005), and UMC (p = 0.007) at the same GA. 30% of mothers in TTTS group have PTSD during pregnancy. 50% of TTTS- patients present an anxiety score over the threshold (STAI-Scale), with a score significantly higher in TTTS than in UMC (p<0.001) or DC (p<0.001). The proportion of subject with a STAI–State over the threshold is also significantly higher in TTTS than in DC at 20 GW (p = 0.01) and at 26 GW (p<0.05). The STAI-state scores in UMC and DC increase progressively during pregnancy while they decrease significantly in TTTS. TTTS announcement constitutes a traumatic event during a pregnancy with an important risk of PTSD, high level of anxiety and an alteration of the prenatal attachment. These results should guide the psychological support provided to these patients.