Immunisation with Transgenic L. tarentolae Expressing Gamma Glutamyl Cysteine Synthetase from Pathogenic Leishmania Species Protected against L. major and L. donovani Infection in a Murine Model

Leishmaniasis is a protozoan disease responsible for significant morbidity and mortality. There is no recommended vaccine to protect against infection. In this study, transgenic Leishmania tarentolae expressing gamma glutamyl cysteine synthetase (γGCS) from three pathogenic species were produced and their ability to protect against infection determined using models of cutaneous and visceral leishmaniasis. The ability of IL-2-producing PODS^® to act as an adjuvant was also determined in L. donovani studies. Two doses of the live vaccine caused a significant reduction in L. major (p < 0.001) and L. donovani (p < 0.05) parasite burdens compared to their respective controls. In contrast, immunisation with wild type L. tarentolae, using the same immunisation protocol, had no effect on parasite burdens compared to infection controls. Joint treatment with IL-2-producing PODS^® enhanced the protective effect of the live vaccine in L. donovani studies. Protection was associated with a Th1 response in L. major and a mixed Th1/Th2 response in L. donovani, based on specific IgG1 and IgG2a antibody and cytokine production from in vitro proliferation assays using antigen-stimulated splenocytes. The results of this study provide further proof that γGCS should be considered a candidate vaccine for leishmaniasis.

[Inguinal hernia operations-Always outpatient?]

Inguinal hernia operations represent the most frequent operations overall with 300,000 interventions annually in Germany, Austria and Switzerland (DACH region). Despite the announced political willingness and the increasing pressure from the legislator to avoid costly inpatient treatment by carrying out as many outpatient operations as possible, outpatient treatment has so far played a subordinate role in the DACH region. The Boards of the specialist societies the German Hernia Society (DHG), the Surgical Working Group Hernia (CAH of the DHG), the Austrian Hernia Society (ÖHG) and the Swiss Working Group Hernia Surgery (SAHC) make inroads into this problem, describe the initial position and assess the current situation.

Structure and function of non-digestible carbohydrates in the gut microbiome

Together with proteins and fats, carbohydrates are one of the macronutrients in the human diet. Digestible carbohydrates, such as starch, starch-based products, sucrose, lactose, glucose and some sugar alcohols and unusual (and fairly rare) α-linked glucans, directly provide us with energy while other carbohydrates including high molecular weight polysaccharides, mainly from plant cell walls, provide us with dietary fibre. Carbohydrates which are efficiently digested in the small intestine are not available in appreciable quantities to act as substrates for gut bacteria. Some oligo- and polysaccharides, many of which are also dietary fibres, are resistant to digestion in the small intestines and enter the colon where they provide substrates for the complex bacterial ecosystem that resides there. This review will focus on these non-digestible carbohydrates (NDC) and examine their impact on the gut microbiota and their physiological impact. Of particular focus will be the potential of non-digestible carbohydrates to act as prebiotics, but the review will also evaluate direct effects of NDC on human cells and systems.

3D-quantitated lung perfusion SPECT/CT: Impact on intended management compared to lung perfusion scan in marginal candidates for lung resection surgery

Objective

Based on previous studies, single-photon emission computed tomography/computed tomography (SPECT/CT) has been proven to be more accurate and reproducible than planar lung perfusion scintigraphy. We conducted a study to evaluate the impact of 3D-quantitated lung perfusion SPECT/CT on intended management in candidates for lung resection surgery.

Methods

Retrospective study including candidates for lung resection surgery with lung perfusion imaging. Patients underwent preoperative evaluation according to ERS/ESTS algorithm. The lobar contribution to the total lung perfusion was estimated using planar antero-posterior, posterior oblique and three-dimensional anatomical SPECT/CT method (CT Pulmo 3D and xSPECT- Quant, Siemens). The difference in lobar perfusion with resulting changes in the extent of lung resection were analyzed to reveal possible changes in operability.

Results

120 patients (46 females) with known lung cancer or pulmonary lesion considered for resection with available lung perfusion scintigraphy and SPECT/CT were enrolled. The mean age (±SD) of patients was 68 ±9 years, the target lesions were located in upper lobe in 57.7% and in lower lobe in 33.5%. The median [IQR] FEV1 was 70.5% [52–84] and median DLCO 56.6% [47.1–67.4]. The planar posterior oblique method, compared to 3D-quantitated SPECT/CT, underestimated the perfusion of upper lobes by a median difference of 5% (right [2–9; IQR]; left [2.5–8], p= &lt; 0.0001), while it overestimated the both lower lobes (left by 4% [2–7]; right by 6% [2–9], p= &lt; 0.0001). In contrast to the planar scintigraphy based evaluation, 4(3.3%) patients with upper lobe lesions were classified as inoperable when 3D-quantitated SPECT/CT was used for calculation of predicted postoperative lung function.

Conclusion

In selected patients with upper lobe lesions, 3D-quantitated SPECT/CT would have changed the treatment strategy from operable to inoperable. Importantly, post-operative mortality in this particular subgroup was disproportionally high. 3D-quantitated SPECT/CT shall be further evaluated as it might improve preoperative risk stratification in marginal lung resection candidates.

Absence of DEATH kinesin is fatal for Leishmania mexicana amastigotes

Kinesins are motor proteins present in organisms from protists to mammals playing important roles in cell division, intracellular organisation and flagellum formation and maintenance. Leishmania mexicana is a protozoan parasite of the order Kinetoplastida causing human cutaneous leishmaniasis. Kinetoplastida genome sequence analyses revealed a large number of kinesins showing sequence and structure homology to eukaryotic kinesins. Here, we investigate the L. mexicana kinesin LmxKIN29 (LmxM.29.0350), also called DEATH kinesin. The activated MAP kinase LmxMPK3, a kinase affecting flagellum length in Leishmania, is able to phosphorylate recombinant full length LmxKIN29 at serine 554. Insect promastigote LmxKIN29 Leishmania null mutants showed no obvious phenotype. However, in mouse infection experiments, the null mutants were unable to cause the disease, whereas LmxKIN29 add-backs and single allele knockouts caused footpad lesions. Localisation using promastigotes expressing GFP-tagged LmxKIN29 revealed that the kinesin is predominantly found in between the nucleus and the flagellar pocket, while in dividing cells the GFP-fusion protein was found at the anterior and posterior ends of the cells indicating a role in cytokinesis. The inability to cause lesions in infected animals and the amino acid sequence divergence from mammalian kinesins suggests that LmxKIN29 is a potential drug target against leishmaniasis.

Shunt Dependence after Intraventricular Hemorrhage and Intraventricular Fibrinolysis with uPA versus rt-PA

BACKGROUND

 We compare the effect of urokinase (urokinase-type plasminogen activator [uPA]) versus alteplase (recombinant tissue plasminogen activator [rt-PA]) for intraventricular fibrinolysis (IVF) in patients with intraventricular hemorrhage (IVH) on ventriculoperitoneal shunt (VPS) dependence, functional outcome, and complications in the management of IVH.

METHODS

 We retrospectively reviewed the patients admitted with IVH or intracerebral hemorrhage (ICH) with IVH within 7 years in three different departments and found 102 patients who met the inclusion criteria. The primary end points were VPS dependence and Glasgow outcome score (GOS) at 3 months. Secondary end points were rate of rebleeding under IVF and incidence of treatment-related complications. Patients were divided into three groups: group I comprised patients treated with external ventricular drain (EVD) and IVF with uPA; group II comprised patients treated with EVD and IVF with rt-PA; and group III comprised patients treated with EVD alone.

RESULTS

 In all, 9.8% patients needed VPS: 12.2% in group I and 15.0% in group II, with no statistically significant difference. VPS patients had higher values of the modified Graeb score (mGS), IVH score, and IVH volume. We saw a trend for a better outcome in group II, with six patients achieving a GOS of 4 or 5 after 3 months. The mortality rate was higher in groups I and III. We found no statistical difference in the complication rate between groups I and II. Logistic regression analysis revealed that higher mGS and age predicted worse prognosis concerning mortality. The risk for death rose by 7.8% for each year of age. Any additional mGS point increased the chances of death by 9.7%.

CONCLUSION

 Our data suggest that both uPA and rt-PA are safe and comparable regarding incidence of communicating hydrocephalus, and age and mGS are predictive for mortality.

Mapping Cell Viability Quantitatively and Independently From Cell Density in 3D Gels Noninvasively

OBJECTIVE

In biomanufacturing there is a need for quantitative methods to map cell viability and density inside 3D bioreactors to assess health and proliferation over time. Recently, noninvasive MRI readouts of cell density have been achieved. However, the ratio of live to dead cells was not varied. Herein we present an approach for measuring the viability of cells embedded in a hydrogel independently from cell density to map cell number and health.

METHODS

Independent quantification of cell viability and density was achieved by calibrating the 1H magnetization transfer- (MT) and diffusion-weighted NMR signals to samples of known cell density and viability using a multivariate approach. Maps of cell viability and density were generated by weighting NMR images by these parameters post-calibration.

RESULTS

Using this method, the limits of detection (LODs) of total cell density and viable cell density were found to be 3.88 ×108 cells · mL -1· Hz -1/2 and 2.36 ×109 viable cells · mL -1· Hz -1/2 respectively.

CONCLUSION

This mapping technique provides a noninvasive means of visualizing cell viability and number density within optically opaque bioreactors.

SIGNIFICANCE

We anticipate that such nondestructive readouts will provide valuable feedback for monitoring and controlling cell populations in bioreactors.

Chest wall stabilization and rib fixation using a nitinol screwless system in selected patients after blunt trauma: Long-term results in a single-center experience

Objective

First experience with rib fixation by use of nitinol in terms of reliability, morbidity, influence on pain control and quality of life in a large series of selected patients after blunt chest trauma.

Methods

Data of all patients who underwent rib fixation by use of nitinol were retrospectively analyzed in terms of indications, morbidity and in-hospital mortality. Standard clinical and radiological follow-up was performed at 1, 3, 6, 12 months after discharge. Short-, mid- and long-term pain status and health related quality of life (HRQOL) were assessed using visual analogous scale (VAS) and short form 12 (SF-12) questionnaire.

Results

From September 2017 until April 2019, 70 patients underwent rib fixation by use of the nitinol device, consisting of dislocated and painful fractures (67.1%), pseudarthrosis (15.7%), emergencies with hemodynamical instability (8.6%), and flail chest (8.6%). Morbidity was 21.4% without wound infection; in-hospital mortality was 2.9%. Fracture of the material occurred in 5.7% of the patients during the first year but removal of the material was not necessary. Analysis of the pain score showed a decrease of the pain with a statistical significance for the whole collective and in the group with series of dislocated fractures (p &lt; 0.001, linear mixed-effects models). Assessment of HRQOL revealed a significant improvement of the physical and mental score for the mid- and long-term analysis.

Conclusion

Our results suggest that rib fixation with nitinol device is reliable, associated with an acceptable morbidity, and significantly decreases pain and improves health related quality of life.

Spermatic cord liposarcomas incidentally found during hernia surgery: is histology of any lipoma mandatory? A review of the literature

Purpose: Liposarcomas found incidentally during open or laparoscopic inguinal hernia surgery are extremely rare. It is unclear, whether any adipose tissue being removed during inguinal hernia surgery must be sent for histology due to the potential risk of liposarcoma of the spermatic cord. This study aims to evaluate the frequency of liposarcomas incidentally found in the inguinal canal during hernia surgery and tries to derive evidence-based recommendations regarding the optimal management of any fatty tissue found in the inguinal canal.Methods: A literature review of the PubMed/Medline electronic databases between January 1980 and January 2019 was performed using the search terms 'inguinal hernia' and 'liposarcoma'. There was only one study available on this topic. Therefore, an additional literature review was performed analyzing all reports on patients with incidentally detected liposarcomas of the spermatic cord in the inguinal canal during hernia surgery.Results: There was only one retrospective study evaluating the frequency of inguinal liposarcoma found at hernia operations with a frequency of less than 0.1%. There were 18 cases of spermatic cord liposarcomas that were truly found incidentally during operation for an unsuspected symptomatic or incarcerated inguinal hernia. These included 16 case reports with a total of 18 patients and 19 liposarcomas. All patients were male with a median age of 62.5 years (range: 24-86 years) years. Median size of liposarcoma was 10.5 cm (range: 3-30 cm). In seven patients, the inguinal liposarcoma was an extension of a retroperitoneal sarcoma. Treatment consisted of radical orchidectomy during the primary operation in 12 patients. Three out of the seven patients with retroperitoneal extension of the tumor underwent a secondary operation with complete resection of the tumor.Conclusions: Currently, there is no evidence-based recommendation available regarding the management of lipomas detected during open or laparoscopic inguinal hernia surgery. Due to the extremely low risk of the presence of a liposarcoma, routine histologic examination cannot be recommended unless the diameter exceeds 10 cm.

Glycan–glycan interactions determine Leishmania attachment to the midgut of permissive sand fly vectors

Force spectroscopy was used to measure the adhesion of Leishmania to synthetic mimics of galectins on the sand fly midgut.

The Smallest Intestine (TSI)-a low volume in vitro model of the small intestine with increased throughput

There is a growing interest in understanding the fate and behaviour of probiotic microorganisms and bioactive compounds during passage of the human gastrointestinal tract (GIT). Here, we report the development of a small volume in vitro model called The smallest Intestine (TSI) with increased throughput focusing on simulating passage through the stomach and small intestine (SI). The basic TSI module consists of five reactors, with a working volume of 12 ml each. During the simulated passage through the SI, bile is absorbed and pH is adjusted to physiologically relevant values for duodenum, jejunum and ileum. A consortium of seven representative bacterial members of the ileum microbiota is included in the ileal stage of the model. The behaviour of three putative probiotic Lactobacillus strains during in vitro simulated upper GIT passage was tested in the model and results were compared to previous studies describing probiotic survival. It was found, that probiotic persistence is strongly related to whether food was ingested, but also to presence of the ileal microbiota, which significantly impacted probiotic survival. In conclusion, TSI allows testing a substantial number of samples, at low cost and short time, and is thus suitable as an in vitro screening platform.

Efficient Concentration of an Amino Acid Using Reactive Extraction Coupled with Bipolar Electrodialysis

One intention of the PRODIAS (processing diluted aqueous systems) project is to develop and establish a toolbox of innovative and tailored separation technologies applicable to design energy-efficient water removal and product recovery techniques. Within this project, the recovery of γ-aminobutyric acid (GABA) was investigated. Using both synthetic as well as fermented solutions, reactive extraction of GABA with the solvent di-(2-ethylhexyl)phosphoric acid + isododecane was performed. For back extraction, different mineral acids were examined. Multistage countercurrent reactive extraction using pH adjustments along the stages to increase extraction efficiency as well as back extraction were then run on pilot-plant scale with fermented GABA solutions. The resulting GABA salt from back extraction was finally split by means of bipolar electrodialysis.

Leishmania donovani 90 kD Heat Shock Protein - Impact of Phosphosites on Parasite Fitness, Infectivity and Casein Kinase Affinity

Leishmania parasites are thought to control protein activity at the post-translational level, e.g. by protein phosphorylation. In the pathogenic amastigote, the mammalian stage of Leishmania parasites, heat shock proteins show increased phosphorylation, indicating a role in stage-specific signal transduction. Here we investigate the impact of phosphosites in the L. donovani heat shock protein 90. Using a chemical knock-down/genetic complementation approach, we mutated 11 confirmed or presumed phosphorylation sites and assessed the impact on overall fitness, morphology and in vitro infectivity. Most phosphosite mutations affected the growth and morphology of promastigotes in vitro, but with one exception, none of the phosphorylation site mutants had a selective impact on the in vitro infection of macrophages. Surprisingly, aspartate replacements mimicking the negative charge of phosphorylated serines or threonines had mostly negative impacts on viability and infectivity. HSP90 is a substrate for casein kinase 1.2-catalysed phosphorylation in vitro. While several putative phosphosite mutations abrogated casein kinase 1.2 activity on HSP90, only Ser₂₈₉ could be identified as casein kinase target by mass spectrometry. In summary, our data show HSP90 as a downstream client of phosphorylation-mediated signalling in an organism that depends on post-transcriptional gene regulation.

Noninvasive Quantification of Cell Density in Three-Dimensional Gels by MRI

OBJECTIVE

For tissue engineering, there is a need for quantitative methods to map cell density inside three-dimensional (3-D) bioreactors to assess tissue growth over time. The current cell mapping methods in 2-D cultures are based on optical microscopy. However, optical methods fail in 3-D due to increased opacity of the tissue. We present an approach for measuring the density of cells embedded in a hydrogel to generate quantitative maps of cell density in a living, 3-D tissue culture sample.

METHODS

Quantification of cell density was obtained by calibrating the ¹H T₂, magnetization transfer (MT) and diffusion-weighted nuclear magnetic resonance (NMR) signals to samples of known cell density. Maps of cell density were generated by weighting NMR images by these parameters post-calibration.

RESULTS

The highest sensitivity weighting arose from MT experiments, which yielded a limit of detection (LOD) of [Formula: see text] cells/mL/ √{Hz} in a 400 MHz (9.4 T) magnet.

CONCLUSION

This mapping technique provides a noninvasive means of visualizing cell growth within optically opaque bioreactors.

SIGNIFICANCE

We anticipate that such readouts of tissue culture growth will provide valuable feedback for controlled cell growth in bioreactors.

Continuous hyperpolarization with parahydrogen in a membrane reactor

Hyperpolarization methods entail a high potential to boost the sensitivity of NMR. Even though the "Signal Amplification by Reversible Exchange" (SABRE) approach uses para-enriched hydrogen, p-H₂, to repeatedly achieve high polarization levels on target molecules without altering their chemical structure, such studies are often limited to batch experiments in NMR tubes. Alternatively, this work introduces a continuous flow setup including a membrane reactor for the p-H₂, supply and consecutive detection in a 1 T NMR spectrometer. Two SABRE substrates pyridine and nicotinamide were hyperpolarized, and more than 1000-fold signal enhancement was found. Our strategy combines low-field NMR spectrometry and a membrane flow reactor. This enables precise control of the experimental conditions such as liquid and gas pressures, and volume flow for ensuring repeatable maximum polarization.

Functional connectivity alterations in patients with chronic hepatitis C virus infection: A multimodal MRI study

Chronic hepatitis C virus (HCV) infection is associated with fatigue and depression. Cognitive impairments are also reported in a smaller number of HCV-positive patients. Recent studies linked HCV to low-grade inflammation in brain. Here, we test the hypothesis that chronic HCV is associated with 3T-neuroimaging-derived grey matter volume (GMV) and functional connectivity alterations in a sample of chronic HCV (1b), without severe liver disease. Regional GMV and resting-state fMRI-derived eigenvector centrality (EC) were compared between 19 HCV-positive patients and 23 healthy controls (all females, 50-69 and 52-64 years, respectively), controlling for white matter hyperintensities and age. Standard tests were used to assess fatigue, depression and cognitive performance. Also, liver fibrosis stage and viral load were quantified among patients. In comparison with controls, HCV-positive patients had higher scores in fatigue and depression, and worse alertness scores. The groups performed similarly in other cognitive domains. We report higher EC in a cluster in the right anterior superior parietal lobule in patients, while no differences are found in GMV. Post hoc functional connectivity analysis showed increased connectivity of this cluster with primary and secondary somatosensory cortex, and temporal and occipital lobes in patients. Higher mean EC in the superior parietal cluster, adjusted for mean framewise displacement, was associated with better memory and attention performance, but not with fatigue, depression, viral load or level of liver fibrosis, among patients. These results suggest a compensatory mechanism in chronic hepatitis C and explain equivocal results in the literature about cognitive deficits in infected persons. Further studies should define the relation of these connectivity changes to the brain's inflammatory activity.

No Significant Cytotoxic Effect of the EZH2 Inhibitor Tazemetostat (EPZ-6438) on Pediatric Glioma Cells with Wildtype Histone 3 or Mutated Histone 3.3

BACKGROUND

Glioblastoma multiforme (GBM) and diffuse intrinsic pontine glioma (DIPG) belong to the most aggressive cancers in children with poor prognosis and limited therapeutic options. Therapeutic targeting of epigenetic proteins may offer new treatment options. Preclinical studies identified Enhancer of Zeste Homolog 2 (EZH2) within polycomb repressor complex 2 (PRC2) as a potential epigenetic anti-tumor target in adult GBM cells but similar inhibition studies in pediatric GBM/DIPG were still missing. Moreover, approximately 30% of pediatric high grade gliomas (pedHGG) including GBM and DIPG harbor a lysine 27 mutation (K27M) in histone 3.3 (H3.3) which is correlated with poor outcome and was shown to influence EZH2 function.

PATIENTS, MATERIALS AND METHODS

The present study investigated the correlation of expression of EZH2 and other PRC2 genes (EZH1, SUZ12, EED) with overall survival of pediatric GBM patients and the cytotoxic impact of EZH2 inhibition by the novel agent Tazemetostat in pediatric GBM/DIPG cells harboring either a H3.3 mutation or a H3 wildtype.

RESULTS

EZH2 gene expression does not correlate with survival of pedHGG patients, and EZH2 inhibition does not induce significant cytotoxicity in pedHGG cells independently of H3.3 mutations.

DISCUSSION AND CONCLUSION

We suggest that EZH2 inhibition might not offer an effective single agent treatment option for paedHGG patients. However, the therapeutic efficacy in combination with cytotoxic and/or other epigenetically active agents still has to be elucidated.

An Arginine Deprivation Response Pathway Is Induced in Leishmania during Macrophage Invasion

Amino acid sensing is an intracellular function that supports nutrient homeostasis, largely through controlled release of amino acids from lysosomal pools. The intracellular pathogen Leishmania resides and proliferates within human macrophage phagolysosomes. Here we describe a new pathway in Leishmania that specifically senses the extracellular levels of arginine, an amino acid that is essential for the parasite. During infection, the macrophage arginine pool is depleted due to its use to produce metabolites (NO and polyamines) that constitute part of the host defense response and its suppression, respectively. We found that parasites respond to this shortage of arginine by up-regulating expression and activity of the Leishmania arginine transporter (LdAAP3), as well as several other transporters. Our analysis indicates the parasite monitors arginine levels in the environment rather than the intracellular pools. Phosphoproteomics and genetic analysis indicates that the arginine-deprivation response is mediated through a mitogen-activated protein kinase-2-dependent signaling cascade.

Protozoa of the genus Leishmania are the causative agents of leishmaniasis in humans. These parasites cycle between promastigotes in the sand fly mid-gut and amastigotes in phagolysosome of mammalian macrophages. During infection, host cells up-regulate nitric oxide while/or parasites induce expression of host arginase, both of which use arginine as a substrate. These elevated activities deplete macrophage arginine pools, a situation that invading Leishmania must overcome since it is an essential amino acid. Leishmania donovani imports exogenous arginine via a mono-specific amino acid transporter (AAP3) and utilizes it primarily through the polyamine pathway to provide precursors for trypanothione biosynthesis as well as hypusination of eukaryotic translation Initiation Factor 5A. Here we report the discovery of a pathway whereby Leishmania sense the lack of environmental arginine and respond with rapid up-regulation in the expression and activity of AAP3, as well as several other transporters. Significantly, this arginine deprivation response is also activated in parasites during macrophage infection. Phosphoproteomic analyses of L. donovani promastigotes have implicated a mitogen-activated protein kinase 2 (MPK2)-mediated signaling cascade in this response, and L. mexicana mutants lacking MPK2 are unable to respond to arginine deprivation. The arginine-sensing pathway might play an important role in Leishmania virulence and hence serve as target for drug development.

Sensitive CH4 detection applying quantum cascade laser based optical feedback cavity-enhanced absorption spectroscopy

We report on sensitive detection of atmospheric methane employing quantum cascade laser based optical feedback cavity-enhanced absorption spectroscopy (OF-CEAS). An instrument has been built utilizing a continuous-wave distributed feedback quantum cascade laser (cw-QCL) with a V-shaped cavity, a common arrangement that reduces feedback to the laser from non-resonant reflections. The spectrometer has a noise equivalent absorption coefficient of 3.6 × 10^-9 cm^-1 Hz^-1/² for a spectral scan of CH₄ at 7.39 μm. From an Allan-Werle analysis a detection limit of 39 parts per trillion of CH₄ at atmospheric pressure within 50 s acquisition time was found.

Sorption Behavior of Compressed CO2 and CH4 on Ultrathin Hybrid Poly(POSS-imide) Layers

Sorption of compressed gases into thin polymeric films is essential for applications including gas sensors and membrane based gas separation. For glassy polymers, the sorption behavior is dependent on the nonequilibrium status of the polymer. The uptake of molecules by a polymer is generally accompanied by dilation, or swelling, of the polymer material. In turn, this dilation can result in penetrant induced plasticization and physical aging that affect the nonequilibrium status of the polymer. Here, we investigate the dilation and sorption behavior of ultrathin membrane layers of a hybrid inorganic-organic network material that consists of alternating polyhedral oligomeric silsesquioxane and imide groups, upon exposure to compressed carbon dioxide and methane. The imide precursor contains fluoroalkene groups that provide affinity toward carbon dioxide, while the octa-functionalized silsesquioxane provides a high degree of cross-linking. This combination allows for extremely high sorption capacities, while structural rearrangements of the network are hindered. We study the simultaneous uptake of gases and dilation of the thin films at high pressures using spectroscopic ellipsometry measurements. Ellipsometry provides the changes in both the refractive index and the film thickness, and allows for accurate quantification of sorption and swelling. In contrast, gravimetric and volumetric measurements only provide a single parameter; this does not allow an accurate correction for, for instance, the changes in buoyancy because of the extensive geometrical changes of highly swelling films. The sorption behavior of the ultrathin hybrid layers depends on the fluoroalkene group content. At low pressure, the apparent molar volume of the gases is low compared to the liquid molar volume of carbon dioxide and methane, respectively. At high gas concentrations in the polymer film, the apparent molar volume of carbon dioxide and methane exceeds that of the liquid molar volume, and approaches that of the gas phase. The high sorption capacity and reversible dilation characteristics of the presented materials provide new directions for applications including gas sensors and gas separation membranes.

Transgenic analysis of the Leishmania MAP kinase MPK10 reveals an auto-inhibitory mechanism crucial for stage-regulated activity and parasite viability

Protozoan pathogens of the genus Leishmania have evolved unique signaling mechanisms that can sense changes in the host environment and trigger adaptive stage differentiation essential for host cell infection. The signaling mechanisms underlying parasite development remain largely elusive even though Leishmania mitogen-activated protein kinases (MAPKs) have been linked previously to environmentally induced differentiation and virulence. Here, we unravel highly unusual regulatory mechanisms for Leishmania MAP kinase 10 (MPK10). Using a transgenic approach, we demonstrate that MPK10 is stage-specifically regulated, as its kinase activity increases during the promastigote to amastigote conversion. However, unlike canonical MAPKs that are activated by dual phosphorylation of the regulatory TxY motif in the activation loop, MPK10 activation is independent from the phosphorylation of the tyrosine residue, which is largely constitutive. Removal of the last 46 amino acids resulted in significantly enhanced MPK10 activity both for the recombinant and transgenic protein, revealing that MPK10 is regulated by an auto-inhibitory mechanism. Over-expression of this hyperactive mutant in transgenic parasites led to a dominant negative effect causing massive cell death during amastigote differentiation, demonstrating the essential nature of MPK10 auto-inhibition for parasite viability. Moreover, phosphoproteomics analyses identified a novel regulatory phospho-serine residue in the C-terminal auto-inhibitory domain at position 395 that could be implicated in kinase regulation. Finally, we uncovered a feedback loop that limits MPK10 activity through dephosphorylation of the tyrosine residue of the TxY motif. Together our data reveal novel aspects of protein kinase regulation in Leishmania, and propose MPK10 as a potential signal sensor of the mammalian host environment, whose intrinsic pre-activated conformation is regulated by auto-inhibition.

Leishmaniasis is an important human disease caused by Leishmania parasites. A crucial aspect of Leishmania infectivity is its capacity to sense different environments and adapt for survival inside insect vector and vertebrate host by stage differentiation. This process is triggered by environmental changes encountered in these organisms, including temperature and pH shifts, which usually are sensed and transduced by signaling cascades including protein kinases and their substrates. In this study, we analyzed the regulation of the Leishmania mitogen-activated protein kinase MPK10 using protein purified from transgenic parasites and combining site-directed mutagenesis and activity tests. We demonstrate that this kinase is activated during parasite differentiation and regulated by an atypical mechanism involving auto-inhibition, which is essential for parasite viability.

Scenario planning for community development in Vietnam: a new tool for integrated health approaches?

Background

Like many countries in Southeast Asia, Vietnam's rapid population and economic growth has met challenges in infrastructure development, especially sanitation in rural areas.

Objective

As an entry point, we developed scenario planning as an action–research tool in a peri-urban community to identify first steps towards improving their complex sanitation problem and to, systemically, address emerging/re-emerging infectious diseases, as these are commonly linked to unsafe water and inadequate sanitation conditions. As an integrated approach, the process of constructing scenarios allowed us to work across sectors and stakeholders to incorporate this knowledge into a common vision.

Design

We conducted focus group discussions to identify and rank driving forces, orally constructed scenarios for the most uncertain drivers, discussed scenario implications and options, and examined the overall process for usefulness and sustainability. During a one-month scoping phase and in between focus group meetings, we carried out household visits which helped us understand the context of data and gather feedback from participants outside of the formal data collection process. Recorded results from these activities were used to develop subsequent tools.

Results and Conclusions

The research process gave us insights into how to adapt the scenario planning tool to identify alternative options. This involved choosing boundary partners, negotiating priorities, drawing out participant learning through self-assessment of our process (a prerequisite for changing mental models and thus achieving outcomes), and understanding how conveyed messages may reinforce the status quo. These insights showed the importance of examining research results beyond outputs and outcomes, namely through process.

What is talked about? Community living staff experiences of talking with older people with intellectual disability about dying and death

BACKGROUND

The aim of this study was to explore what community living staff talked about and did with people with intellectual disability (ID) to assist them to understand dying and death.

METHOD

Guided by grounded theory methodology, focus groups and one-to-one interviews were conducted with 22 staff who had talked about any topic relating to dying and death with their clients.

RESULTS

There was little evidence that staff talked with, or did things with clients to assist understanding of the end of life, both prior to and after a death. Prior to death staff assisted clients in a limited way to understand about determining wishes in preparation for death, and what dying looks like by observance of its passage. Following a death staff offered limited assistance to clients to understand the immutability of death, and how the dead can be honoured with ritual, and remembered.

CONCLUSIONS

The findings have implications for why people with ID have only partial understanding of the end of life, the staff skills required to support clients' understanding, and when conversations about the end of life should occur.

The Leishmania donovani chaperone cyclophilin 40 is essential for intracellular infection independent of its stage-specific phosphorylation status

During its life cycle, the protozoan pathogen Leishmania donovani is exposed to contrasting environments inside insect vector and vertebrate host, to which the parasite must adapt for extra- and intracellular survival. Combining null mutant analysis with phosphorylation site-specific mutagenesis and functional complementation we genetically tested the requirement of the L. donovani chaperone cyclophilin 40 (LdCyP40) for infection. Targeted replacement of LdCyP40 had no effect on parasite viability, axenic amastigote differentiation, and resistance to various forms of environmental stress in culture, suggesting important functional redundancy to other parasite chaperones. However, ultrastructural analyses and video microscopy of cyp40-/- promastigotes uncovered important defects in cell shape, organization of the subpellicular tubulin network and motility at stationary growth phase. More importantly, cyp40-/- parasites were unable to establish intracellular infection in murine macrophages and were eliminated during the first 24 h post infection. Surprisingly, cyp40-/- infectivity was restored in complemented parasites expressing a CyP40 mutant of the unique S274 phosphorylation site. Together our data reveal non-redundant CyP40 functions in parasite cytoskeletal remodelling relevant for the development of infectious parasites in vitro independent of its phosphorylation status, and provide a framework for the genetic analysis of Leishmania-specific phosphorylation sites and their role in regulating parasite protein function.

Recurrent mutations, including NPM1c, activate a BRD4-dependent core transcriptional program in acute myeloid leukemia

Recent evidence suggests that inhibition of bromodomain and extra-terminal (BET) epigenetic readers may have clinical utility against acute myeloid leukemia (AML). Here we validate this hypothesis, demonstrating the efficacy of the BET inhibitor I-BET151 across a variety of AML subtypes driven by disparate mutations. We demonstrate that a common 'core' transcriptional program, which is HOX gene independent, is downregulated in AML and underlies sensitivity to I-BET treatment. This program is enriched for genes that contain 'super-enhancers', recently described regulatory elements postulated to control key oncogenic driver genes. Moreover, our program can independently classify AML patients into distinct cytogenetic and molecular subgroups, suggesting that it contains biomarkers of sensitivity and response. We focus AML with mutations of the Nucleophosmin gene (NPM1) and show evidence to suggest that wild-type NPM1 has an inhibitory influence on BRD4 that is relieved upon NPM1c mutation and cytosplasmic dislocation. This leads to the upregulation of the core transcriptional program facilitating leukemia development. This program is abrogated by I-BET therapy and by nuclear restoration of NPM1. Finally, we demonstrate the efficacy of I-BET151 in a unique murine model and in primary patient samples of NPM1c AML. Taken together, our data support the use of BET inhibitors in clinical trials in AML.

BET protein inhibition shows efficacy against JAK2V617F-driven neoplasms

Small molecule inhibition of the BET family of proteins, which bind acetylated lysines within histones, has been shown to have a marked therapeutic benefit in pre-clinical models of mixed lineage leukemia (MLL) fusion protein-driven leukemias. Here, we report that I-BET151, a highly specific BET family bromodomain inhibitor, leads to growth inhibition in a human erythroleukemic (HEL) cell line as well as in erythroid precursors isolated from polycythemia vera patients. One of the genes most highly downregulated by I-BET151 was LMO2, an important oncogenic regulator of hematopoietic stem cell development and erythropoiesis. We previously reported that LMO2 transcription is dependent upon Janus kinase 2 (JAK2) kinase activity in HEL cells. Here, we show that the transcriptional changes induced by a JAK2 inhibitor (TG101209) and I-BET151 in HEL cells are significantly over-lapping, suggesting a common pathway of action. We generated JAK2 inhibitor resistant HEL cells and showed that these retain sensitivity to I-BET151. These data highlight I-BET151 as a potential alternative treatment against myeloproliferative neoplasms driven by constitutively active JAK2 kinase.

Predictors associated with treatment initiation and switch in a real-world chronic hepatitis B population from five European countries

In Europe, healthcare systems differ between countries and different factors may influence Chronic hepatitis B (CHB) treatment choices in different counties. This analysis from a prospective, longitudinal, non-interventional study in five EU countries aimed to explore determinants associated with treatment initiation or switch in patients with CHB. A total of 1267 adult patients with compensated CHB in Germany, France, Poland, Romania and Turkey were prospectively followed for up to 2 years (March 2008-December 2010). Determinants of treatment initiation or switch were analysed using multivariate Cox proportional hazards regression. Median time since CHB diagnosis was 2.6 (0-37.7) years. Among 646 treatment-naïve patients, the probability of treatment initiation during follow-up was higher: in Germany (P = 0.0006), Poland (P < 0.0001) and Romania (P = 0.0004) compared with Turkey; in patients with alanine transaminase (ALT) 1-2 × upper limit of normal (ULN) (P = 0.0580) or >2 × ULN (P = 0.0523) compared with ALT ≤ 1 × ULN; and in patients with hepatitis B virus (HBV) DNA ≥ 2000 IU/mL (P < 0.0001) compared with HBV DNA <2000 IU/mL or undetectable. Among 567 treated patients, 87 switched treatment during follow-up. The probability of treatment switch was higher: in France (P = 0.0029), Germany (P = 0.0078) and Poland (P = 0.0329) compared with Turkey; and in patients with HBV DNA <2000 (P < 0.0001) or ≥ 2000 IU/mL (P < 0.0001), compared with undetectable. Viral load and ALT level were identified as the major drivers of treatment initiation. HBV DNA level was also a significant determinant of treatment switch. Results were statistically different across EU countries.

'If and when?': the beliefs and experiences of community living staff in supporting older people with intellectual disability to know about dying

BACKGROUND

The aim of this study was to explore the way in which community living staff engaged with people with intellectual disability (ID) about dying and death.

METHOD

Guided by grounded theory methodology, focus groups and individual interviews were conducted with staff who had either no experience with client death, experience of a client sudden death, or a client death experience which was pre-dated by a period of end-of-life care.

RESULTS

While in principle, staff unanimously supported the belief that people with ID should know about dying, there was limited in-practice engagement with clients about the topic. Engagement varied according to staff experience, client capacity to understand and the nature of the 'opportunity' to engage. Four 'opportunities' were identified: 'when family die', 'incidental opportunities', 'when clients live with someone who is dying' and 'when a client is dying'. Despite limited engagement by staff, people with ID are regularly exposed to dying and death.

CONCLUSIONS

People with ID have a fundamental right to know about dying and death. Sophisticated staff skills are required to ensure that people with ID can meaningfully engage with end-of-life issues as opportunities arise.

Reducing short-stay hospital admissions by ruling out non-ST elevation myocardial infarction and estimating coronary artery disease likelihood on an emergency department observation ward

Chest pain is an important presentation in adult patients attending emergency departments (ED). The process of ruling out an acute coronary syndrome (ACS) conventionally requires a short in-patient stay. This places a significant burden on healthcare systems. Recent developments have encouraged us to explore the role of an ED observation ward in the management of these patients.

We designed and implemented two proformas (‘flowformas’). The first provides integrated guidance and documentation for the management of chest pain in the ED. In patients determined to be at low risk of short-term adverse outcomes the ACS rule-out process is now completed on the ED observation ward rather than on the cardio-respiratory admission ward. The second proforma is used before discharge to determine the likelihood of underlying coronary artery disease (CAD), thereby allowing risk-based follow-up arrangements to be made. We collected data on all patients admitted to EDU on the NSTEMI rule-out pathway over a 12-month period.

Between Feb 2012 and Feb 2013, 816 patients fulfilling the criteria were admitted on the pathway. 67 patients (8%) required admission due to ACS. 15 patients were admitted on two, and one on three occasions.

In conclusion, it is possible to deliver ACS rule-out on an emergency observation ward. This reduces healthcare costs and shortens hospital stay.

Using GafChromic film to estimate the effective dose from dental cone beam CT and panoramic radiography

OBJECTIVES

To demonstrate the feasibility of GafChromic(®) XR-QA2 (ISP Corp., Wayne, NJ) as a dosemeter when performing measurements of the effective dose from three cone beam CT (CBCT) units and to compare the doses from examinations of three common dental clinical situations. A second aim was to compare the radiation doses for three digital panoramic units with the doses for the CBCT units.

METHODS

The CBCT units used were Veraviewepocs 3De(®) (J Morita MFG Corp., Kyoto, Japan), ProMax(®) 3D (Planmeca, Helsinki, Finland) and NewTom VGi(®) (Quantitative Radiology, Verona, Italy). GafChromic XR-QA2 films were placed between the selected layers of the head and neck of a tissue-equivalent human skull (RANDO(®) phantom; The Phantom Laboratory, Salem, NY). The exposure parameters were set using the automatic exposure control function of the units. Depending on the availability, medium and smaller field of view (FOV) scanning modes were used. The effective dose was estimated using the 2007 International Commission on Radiological Protection formalism.

RESULTS

The lowest effective dose of a CBCT unit was observed for ProMax 3D, FOV 4 × 5 cm (10 μSv), the highest for NewTom VGi, FOV 8 × 8 cm-high resolution (129 μSv). The range of effective doses for digital panoramic machines measured was 8-14 μSv.

CONCLUSIONS

This study demonstrates the feasibility of using radiochromic films for dental CBCT and panoramic dosimetry.

Diagnostic value of quantitative EUS elastography for malignant pancreatic tumors: relationship with pancreatic fibrosis

PURPOSE

EUS elastography has been used to facilitate the diagnosis of pancreatic cancer, but as yet the interpretation of this procedure has been largely subjective. The present study has been designed to validate a quantitative approach for the analysis of EUS elastography, and to assess its relationship with pancreatic fibrosis.

MATERIALS AND METHODS

86 patients with malignant pancreatic masses and 28 control subjects without any evidence of pancreatic diseases were examined by EUS elastography. EUS video sequences were subjected to a quantitative analysis based on mean hue histogram analysis. Pancreatic fibrosis was determined by quantitative morphometry in tissue specimens from 36 patients.

RESULTS

The mean RGB (red, green, blue) value was significantly higher in the cancer patients compared to the controls (14.0 ± 0.4 vs. 11.5 ± 0.9; p = 0.0085), albeit with significant overlap between the groups. In contrast, a much sharper separation between the groups was obtained based on the individual color values for blue, green and red (p < 0.0001, respectively). By these means, 100 % sensitivity and specificity for the distinction between tumor and normal tissue was obtained for the blue color value, while the red and green color values were less discriminative. The fractional fiber content of the tumors was unrelated to the respective hue histogram color values.

CONCLUSION

Quantitative EUS elastography allows for clear differentiation between malignant pancreatic tumors and normal tissue. Using this approach, we demonstrated that the stiffness of pancreatic tumors is largely independent of their fiber content.