Liquid compound refractive X-ray lens

We introduce the concept of a liquid compound refractive X-ray zoom lens. The lens is generated by pumping a suitable liquid lens material like water, alcohol or heated lithium through a line of nozzles each forming a jet with the cross section of lens elements. The system is housed, so there is a liquid-circulation. This lens can be used in white beam at high brilliance synchrotron sources, as radiation damages are cured by the continuous reformation of the lens. The focal length can be varied by closing nozzles, thus reducing the number of lens elements in the beam.

Design of defect-chemical properties and device performance in memristive systems

Future development of the modern nanoelectronics and its flagships internet of things, artificial intelligence, and neuromorphic computing is largely associated with memristive elements, offering a spectrum of inevitable functionalities, atomic level scalability, and low-power operation. However, their development is limited by significant variability and still phenomenologically orientated materials' design strategy. Here, we highlight the vital importance of materials' purity, demonstrating that even parts-per-million foreign elements substantially change performance. Appropriate choice of chemistry and amount of doping element selectively enhances the desired functionality. Dopant/impurity-dependent structure and charge/potential distribution in the space-charge layers and cell capacitance determine the device kinetics and functions. The relation between chemical composition/purity and switching/neuromorphic performance is experimentally evidenced, providing directions for a rational design of future memristive devices.

Long-term follow-up of 22 psoriatic patients treated with ixekizumab after failure of secukinumab

The original article was published on February 15, 2020 and corrected on March 26, 2020. The revised version of the article amends the table and figure, while leaving the text largely unchanged. The changes appear in the revised online PDF copy of this article.

Long-term follow-up of 22 psoriatic patients treated with ixekizumab after failure of secukinumab

Switching of biologic agents in treatment of plaque psoriasis is a common strategy. Only a few studies are available on switching between IL17A-blockers. In a retrospective study, we identified 22 psoriasis patients who, after failing secukinumab as a first IL17A-blocker received ixekizumab with an observation period of at least 24 weeks. At last observation 10/22 patients had a good response (PASI75 or PASI<3) using ixekizumab therapy. None of five patients with primary non-response to secukinumab reached a good, durable response to ixekizumab. In conclusion, ixekizumab appears to be a therapeutic option as a second IL17A-blocker in psoriasis patients who did not show a primary non-response to secukinumab.

Super-Resolution Scanning Transmission X-Ray Imaging Using Single Biconcave Parabolic Refractive Lens Array

A new super resolution imaging technique which potentially enables sub-µm spatial resolution, using a detector of pixels much larger than the spatial resolution, is proposed. The method utilizes sample scanning through a large number of identical X-ray microprobes periodically spaced (the period corresponds to a multiple of the pixel size), which reduces drastically the scanning time. The information about the sample illuminated by the microprobes is stored by large detector pixels. Using these data and sample position information, a super-resolution image reconstruction is performed. With a one-dimensional (1D) high aspect ratio nickel single lens array designed for theoretically expected sub-µm microprobes at 17 keV and fabricated by deep X-ray lithography and electroforming technique, 2 µm X-ray microprobes with a period of 10 µm were achieved. We performed a first experiment at KARA synchrotron facility, and it was demonstrated that the smallest structure of a test pattern with a size of 1.5 µm could be easily resolved by using images generated from a detector having a pixel size of 10.4 µm. This new approach has a great potential for providing a new microscopic imaging modality with a large field of view and short scan time.

A smart decision: smartphone use for operative data collection in arthroscopic shoulder instability surgery

OBJECTIVE

This study tested validity, accuracy, and efficiency of the Orthopaedic Minimal Data Set Episode of Care (OME) compared with traditional operative report in arthroscopic surgery for shoulder instability. As of November 2017, OME had successfully captured baseline data on 97% of 18 700 eligible cases.

MATERIALS AND METHODS

This study analyzes 100 cases entered into OME through smartphones by 12 surgeons at an institution from February to October 2015. A blinded reviewer extracted the same variables from operative report into a separate database. Completion rates and agreement were compared. They were assessed using raw percentages and McNemar's test (with continuity correction). Agreement between nominal variables was assessed by unweighted Cohen's kappa and a concordance correlation coefficient measured agreement between continuous variables. Efficiency was assessed by median time to complete.

RESULTS

Of 37 variables, OME demonstrated equal or higher completion rates for all but 1 and had significantly higher capture rates for 49% (n = 18; P < .05). Of 33 nominal variables, raw proportional agreement was ≥0.90 for 76% (n = 25). Raw proportional agreement was perfect for 15% (n = 5); no agreement statistic could be calculated due to a single variable in operative note and OME. Calculated agreement statistic was substantial or better (κ > 0.61) for 51% (n = 17) for the 33 nominal variables. All continuous variables assessed (n = 4) demonstrated poor agreement (concordance correlation coefficient <0.90). Median time for completing OME was 103.5 (interquartile range, 80.5-151) seconds.

CONCLUSIONS

The OME smartphone data capture system routinely captured more data than operative report and demonstrated acceptable agreement for nearly all nominal variables, yet took <2 minutes to complete on average.

Validity and efficiency of a smartphone-based electronic data collection tool for operative data in rotator cuff repair

BACKGROUND

This study tested validity and efficiency of Orthopaedic Minimal Data Set (OrthoMiDaS) Episode of Care (OME).

METHODS

We analyzed 100 isolated rotator cuff repair cases in the OME database. Surgeons completed a traditional operative note and OME report. A blinded reviewer extracted data from operative notes and implant logs in electronic medical records by manual chart review. OME and electronic medical record data were compared with data counts and agreement between 40 variables of rotator cuff disease and repair procedures. Data counts were assessed using raw percentages and McNemar test (with continuity correction). Agreement of categorical variables was analyzed using Cohen κ (unweighted) and of numerical variables using the concordance correlation coefficient (CCC). Efficiency was assessed by median time to complete.

RESULTS

OME database had significantly higher data counts for 25% (10/40) of variables. A high level of proportional and statistical agreement was demonstrated between the data. Among 35 categorical variables, proportional agreement was perfect for 17%, almost perfect (0.81 ≤ κ ≤ 1.00) for 37%, substantial (0.61 ≤ κ ≤ 0.80) for 20%, moderate (0.41 ≤ κ ≤ 0.60) for 14%, fair (0.21 ≤ κ ≤ 0.40) for 6%, and slight (0.0 ≤ κ ≤ 0.20) for 6%. Of 5 numerical variables, agreement was almost perfect (CCC > 0.99) for 20% and poor (CCC < 0.90) for 80%. Median OME completion time was 161.5 seconds (interquartile range, 116-224.5).

CONCLUSION

OME is an efficient, valid tool for collecting comprehensive, standardized data on rotator cuff repair.

X-ray zoom lens allows for energy scans in X-ray microscopy

We introduce a new design and development of a compound refractive X-ray zoom lens for energy scans in X-ray microscopy. Energy scans are, in principle, equivalent to radial scans in the reciprocal space for X-ray diffraction. Thanks to the absence of sample or detector motions, energy scans are better suited for microscopy, which requires high stability. In addition, close to the absorption edge of an element, energy scans can yield chemical information when coupled with resonant effects in full field diffraction X-ray microscopy (FFDXM) or X-ray absorption near edge structure (XANES) microscopy. Here, we demonstrate the concept by using a customized compound refractive X-ray zoom lens for 11 keV near the Ge K_α-edge. The working distance and magnification were kept constant during the energy scans by adapting the lens composition on switchable zoom lens fingers. This alleviates the need to reposition the lens while changing the energy and makes quantitative analysis more convenient for FFDXM. The fabricated zoom lens was characterized and proven suitable for the proposed measurement.

Optimizing illumination for full field imaging at high brilliance hard X-ray synchrotron sources

A new technique is presented to overcome beam size limitation in full field imaging at high brilliance synchrotron sources using specially designed refractive X-ray optics. These optics defocus the incoming beam in vertical direction and reshape the intensity distribution from a Gaussian to a more desirable top-hat-shaped profile at the same time. With these optics X-ray full-field imaging of extended objects becomes possible without having to stack several scans or applying a cone beam geometry in order to image the entire specimen. For in situ experiments in general and for diffraction limited sources in particular this gain in field of view and the optimization of the intensity distribution is going to be very beneficial.

Early endothelial progenitor cells and vascular stiffness in psoriasis and psoriatic arthritis

BACKGROUND

Both psoriasis (Ps) and psoriasis arthritis (PsA) have been associated with increased cardiovascular risk. Also, both are characterized by increased neovascularization. Endothelial progenitor cells (EPCs) have been implicated in promoting vascular repair in ischemic diseases. The aim of the study was to correlate the EPC system with CV risk factors and with parameters of vascular stiffness in Ps and PsA.

METHODS

Twenty-six healthy subjects, 30 patients with Ps, and 31 patients PsA were included in the study. eEPC regeneration was evaluated by a colony-forming assay, circulating eEPCs were measured by cytometric analysis. For vascular analysis, all subjects underwent quantification of pulse wave velocity (PWV) and augmentation index (AIX).

RESULTS

Patients were categorized upon the duration of disease, severity of skin involvement (PASI-Ps), individual pain as reflected by the VAS (PsA), CRP values, and history of treatment with one or more biologicals. Regarding the eEPC system, no significant differences were observed between the respective categories. Correlation analyses between parameters of vascular stiffness (PWV and AIX) and patterns of colony formation/circulating eEPCs did not show any correlation at all.

CONCLUSION

Parameters of vascular stiffness are not significantly deteriorated in Ps/PsA. Thus, pulse wave analysis may not be suitable for CVR assessment in certain autoimmune-mediated diseases. Regenerative activity of the eEPC system/circulating eEPC numbers are not altered in Ps/PsA. One may conclude that malfunctions of the eEPC are not substantially involved in perpetuating the micro-/macrovascular alterations in Ps/PsA.

Hypothermia does not influence liver damage and function in a porcine polytrauma model

BACKGROUND

Previous studies revealed evidence that induced hypothermia attenuates ischemic organ injuries after severe trauma. In the present study, the effect of hypothermia on liver damage was investigated in a porcine long term model of multi-system injury, consisting of blunt chest trauma, penetrating abdominal trauma, musculoskeletal injury, and hemorrhagic shockMETHODS: In 30 pigs, a standardized polytrauma including blunt chest trauma, penetrating abdominal trauma, musculoskeletal injury, and hemorrhagic shock of 45% of total blood volume was induced. Following trauma, hypothermia of 33∘C was induced for 12 h and intensive care treatment was evaluated for 48 h. As outcome parameters, we assessed liver function and serum transaminase levels as well as a histopathological analysis of tissue samples. A further 10 animals served as controls.

RESULTS

Serum transaminase levels were increased at the end of the observation period following hypothermia without reaching statistical significance compared to normothermic groups. Liver function was preserved (p⩽ 0.05) after the rewarming period in hypothermic animals but showed no difference at the end of the observation period. In H&E staining, cell death was slightly increased hypothermic animals and caspase-3 staining displayed tendency towards more apoptosis in hypothermic group as well.

CONCLUSIONS

Induction of hypothermia could not significantly improve hepatic damage during the first 48 h following major trauma. Further studies focusing on multi-organ failure including a longer observation period are required to illuminate the impact of hypothermia on hepatic function in multiple trauma patients.

Miniaturized compound refractive X-ray zoom lens

We introduce the concept of a miniaturized compound refractive X-ray zoom lens consisting of SU-8 lenses fabricated by deep X-ray lithography. The focal length can be varied by changing the number of lens elements placed in the beam. We use suitable actuators to move single lens elements reversibly out of the beam. The X-ray zoom lens can accept different X-ray energies while keeping a fixed working distance, or vary the focal distance for a fixed energy. The latter is useful in tuning the magnification factor in full field microscopy.

Disinfection of human musculoskeletal allografts in tissue banking: a systematic review

Musculoskeletal allografts are typically disinfected using antibiotics, irradiation or chemical methods but protocols vary significantly between tissue banks. It is likely that different disinfection protocols will not have the same level of microorganism kill; they may also have varying effects on the structural integrity of the tissue, which could lead to significant differences in terms of clinical outcome in recipients. Ideally, a disinfection protocol should achieve the greatest bioburden reduction with the lowest possible impact on tissue integrity. A systematic review of three databases found 68 laboratory and clinical studies that analyzed the microbial bioburden or contamination rates of musculoskeletal allografts. The use of peracetic acid–ethanol or ionizing radiation was found to be most effective for disinfection of tissues. The use of irradiation is the most frequently published method for the terminal sterilization of musculoskeletal allografts; it is widely used and its efficacy is well documented in the literature. However, effective disinfection results were still observed using the BioCleanse™ Tissue Sterilization process, pulsatile lavage with antibiotics, ethylene oxide, and chlorhexidine. The variety of effective methods to reduce contamination rate or bioburden, in conjunction with limited high quality evidence provides little support for the recommendation of a single bioburden reduction method.

Disinfection of human cardiac valve allografts in tissue banking: systematic review report

Cardiovascular allografts are usually disinfected using antibiotics, but protocols vary significantly between tissue banks. It is likely that different disinfection protocols will not have the same level of efficacy; they may also have varying effects on the structural integrity of the tissue, which could lead to significant differences in terms of clinical outcome in recipients. Ideally, a disinfection protocol should achieve the greatest bioburden reduction with the lowest possible impact on tissue integrity. We conducted a systematic review of methods applied to disinfect cardiovascular tissues. The use of multiple broad spectrum antibiotics in conjunction with an antifungal agent resulted in the greatest reduction in bioburden. Antibiotic incubation periods were limited to less than 24 h, and most protocols incubated tissues at 4 °C, however one study demonstrated a greater reduction of microbial load at 37 °C. None of the reviewed studies looked at the impact of these disinfection protocols on the risk of infection or any other clinical outcome in recipients.

Increasing the field of view in grating based X-ray phase contrast imaging using stitched gratings

Grating based X-ray differential phase contrast imaging (DPCI) allows for high contrast imaging of materials with similar absorption characteristics. In the last years' publications, small animals or parts of the human body like breast, hand, joints or blood vessels have been studied. Larger objects could not be investigated due to the restricted field of view limited by the available grating area. In this paper, we report on a new stitching method to increase the grating area significantly: individual gratings are merged on a carrier substrate. Whereas the grating fabrication process is based on the LIGA technology (X-ray lithography and electroplating) different cutting and joining methods have been evaluated. First imaging results using a 2×2 stitched analyzer grating in a Talbot-Lau interferometer have been generated using a conventional polychromatic X-ray source. The image quality and analysis confirm the high potential of the stitching method to increase the field of view considerably.

Note: Gratings on low absorbing substrates for x-ray phase contrast imaging

Grating based X-ray phase contrast imaging is on the verge of being applied in clinical settings. To achieve this goal, compact setups with high sensitivity and dose efficiency are necessary. Both can be increased by eliminating unwanted absorption in the beam path, which is mainly due to the grating substrates. Fabrication of gratings via deep X-ray lithography can address this issue by replacing the commonly used silicon substrate with materials with lower X-ray absorption that fulfill certain boundary conditions. Gratings were produced on both graphite and polymer substrates without compromising on structure quality. These gratings were tested in a three-grating setup with a source operated at 40 kVp and lead to an increase in the detector photon count rate of almost a factor of 4 compared to a set of gratings on silicon substrates. As the visibility was hardly affected, this corresponds to a significant increase in sensitivity and therefore dose efficiency.

Energy-resolved visibility analysis of grating interferometers operated at polychromatic X-ray sources

Grating interferometry has been successfully adapted at standard X-ray tubes and is a promising candidate for a broad use of phase-contrast imaging in medical diagnostics or industrial testing. The achievable image quality using this technique is mainly dependent on the interferometer performance with the interferometric visibility as crucial parameter. The presented study deals with experimental investigations of the spectral dependence of the visibility in order to understand the interaction between the single contributing energies. Especially for the choice which type of setup has to be preferred using a polychromatic source, this knowledge is highly relevant. Our results affirm previous findings from theoretical investigations but also show that measurements of the spectral contributions to the visibility are necessary to fully characterize and optimize a grating interferometer and cannot be replaced by only relying on simulated data up to now.

Increased age is not associated with higher incidence of complications, longer stay in acute care hospital and in hospital mortality in geriatric hip fracture patients

The number of agile patients in the 10th decade with a strong need for postoperative mobility will increase in the following decades. The present prospective study sought to prove if very old patients with hip-related fractures are disadvantaged according to incidence of complications, length of ICU and in-hospital stay, and in-hospital mortality. We included 402 patients, age 60 years and older, with hip related fractures. Operative treatment consisted of osteosynthesis or endoprothesis. ASA score, body mass index, Charlson Comorbidity Index, Barthel Index and Mini-Mental-Status were documented. We noted length of in-hospital stay and ICU stay as well as readmission to ICU and complications, including their dispersal according to Clavien-Dindo Classification. After univariate analysis, a multivariate analysis was performed. The examined cohorts were 85 patients aged 60-74 years, 253 75-90 years old and 64 >90 year old patients. In-hospital periods (13-14 days) mean stay on ICU (2 days) and frequency of readmission on ICU did not significantly differ statistically. Most complications were grade II, with comparable frequency and modality, displaying no significant difference throughout age-related groups (p=0.461). In-hospital mortality showing significance (p=0.014) only between 75-89 (4.4%) and >90-year-old (12.5%) cohort. Nevertheless, according to multivariate analysis, including the common risk factors, increased age was not an independent risk factor for dying (p=0.132). Patients at an advanced age with hip-related fractures showed neither a prolonged in-hospital nor ICU stay. There was no significant relation of advanced age to number and type of complications.

German evidence-based guidelines for the treatment of Psoriasis vulgaris (short version)

Psoriasis vulgaris is a common and chronic inflammatory skin disease which has the potential to significantly reduce the quality of life in severely affected patients. The incidence of psoriasis in Western industrialized countries ranges from 1.5 to 2%. Despite the large variety of treatment options available, patient surveys have revealed insufficient satisfaction with the efficacy of available treatments and a high rate of medication non-compliance. To optimize the treatment of psoriasis in Germany, the Deutsche Dermatologische Gesellschaft and the Berufsverband Deutscher Dermatologen (BVDD) have initiated a project to develop evidence-based guidelines for the management of psoriasis. The guidelines focus on induction therapy in cases of mild, moderate, and severe plaque-type psoriasis in adults. The short version of the guidelines reported here consist of a series of therapeutic recommendations that are based on a systematic literature search and subsequent discussion with experts in the field; they have been approved by a team of dermatology experts. In addition to the therapeutic recommendations provided in this short version, the full version of the guidelines includes information on contraindications, adverse events, drug interactions, practicality, and costs as well as detailed information on how best to apply the treatments described (for full version, please see Nast et al., JDDG, Suppl 2:S1-S126, 2006; or http://www.psoriasis-leitlinie.de ).

Helicobacter pylori-induced apoptosis in T cells is mediated by the mitochondrial pathway independent of death receptors

BACKGROUND

Chronic infection with Helicobacter pylori is related to the pathogenesis of the noncardia carcinoma of the stomach. In this study we investigated the mechanisms of H. pylori-induced apoptosis in T lymphocytes, which could explain a mechanism of immune evasion facilitating chronic inflammation of the mucosa and gastric carcinogenesis.

MATERIALS AND METHODS

The supernatant of H. pylori culture was used to study the mechanism of apoptosis induction in human leukaemia T cell lines Jurkat and CEM and in primary T cells. The cytotoxin associated gene A (CagA) and vacuolating cytotoxin A (Vac A) positive bacterial strain H. pylori 60190 (CagA(+), VacA(+)) and as a control the less toxic H. pylori strain Tx30a (CagA(-), VacA(-)) were used to produce the supernatant. Cell death was determined by DNA fragmentation and protein expression by Western blot.

RESULTS

H. pylori 60190-induced apoptosis was neither blocked by inhibition of the death ligands TRAIL (TNF-related apoptosis-inducing ligand), CD95L/FasL and TNF-alpha (tumour necrosis factor-a) in wild type Jurkat cells nor in FADD(def) (Fas-associated death domain protein) and caspase-8(def) subclones of the Jurkat cell line. Yet, the pancaspase inhibitor zVAD-fmk could inhibit up to 90% of H. pylori-induced apoptosis. Stable transfection of Jurkat wild type cells with Bcl-x(L and) Bcl-2 resulted in marked reduction of H. pylori-induced apoptosis, showing that the mitochondrial pathway is the key regulator. This is supported by the finding that surviving primary human lymphocytes upregulate Bcl-2 when exposed to H. pylori supernatant.

CONCLUSIONS

H. pylori-induced apoptosis of T cells is mediated by the mitochondrial pathway and could create a local environment that facilitates life-long infection by immune evasion.

Integrating patient safety into the clinical microsystem

Healthcare institutions continue to face challenges in providing safe patient care in increasingly complex organisational and regulatory environments while striving to maintain financial viability. The clinical microsystem provides a conceptual and practical framework for approaching organisational learning and delivery of care. Tensions exist between the conceptual theory and the daily practical applications of providing safe and effective care within healthcare systems. Healthcare organisations are often complex, disorganised, and opaque systems to their users and their patients. This disorganisation may lead to patient discomfort and harm as well as much waste. Healthcare organisations are in some sense conglomerates of smaller systems, not coherent monolithic organisations. The microsystem unit allows organisational leaders to embed quality and safety into a microsystem's developmental journey. Leaders can set the stage for making safety a priority for the organisation while allowing individual microsystems to create innovative strategies for improvement.

Integrating patient safety into the clinical microsystem

Healthcare institutions continue to face challenges in providing safe patient care in increasingly complex organisational and regulatory environments while striving to maintain financial viability. The clinical microsystem provides a conceptual and practical framework for approaching organisational learning and delivery of care. Tensions exist between the conceptual theory and the daily practical applications of providing safe and effective care within healthcare systems. Healthcare organisations are often complex, disorganised, and opaque systems to their users and their patients. This disorganisation may lead to patient discomfort and harm as well as much waste. Healthcare organisations are in some sense conglomerates of smaller systems, not coherent monolithic organisations. The microsystem unit allows organisational leaders to embed quality and safety into a microsystem's developmental journey. Leaders can set the stage for making safety a priority for the organisation while allowing individual microsystems to create innovative strategies for improvement.

Relationships between electrical impedance and fluid losses from turkey breast meat

Abstract. Breast muscles were removed from turkeys soon after slaughter. The meat quality was judged to be normal with little or no evidence of the pale, soft, exudative (PSE) condition. Fluid losses the day after slaughter were 0.50 SD 0.35 %. The most reliable predictor of fluid losses was resistance: r = –0.37 at 120 kHz, –0.30 at 1 Hz and –0.34 at 10 kHz (P < 0.001, n = 156). Between 1 and 4 days post-mortem, the mean drip loss from slices of turkey meat in a cooler was 4.31 SD 1.91%. Resistance was correlated with cooler drip loss: r = –0.61 at 120 Hz, –0.51 at 1 kHz and –0.62 at 10 kHz (P < 0.001, n = 45).

Hemodilution - an overview of current canadian practices

Background. Transplant teams evaluate potential organ and tissue donors to exclude donation of tissues at risk for disease transmission. Standards dictate that serological tests be performed on every donor to assess the presence of transmissible diseases including: Human Immunodeficiency Virus 1 & 2, Human T Lymphotropic Virus 1 & 2, Hepatitis C, Hepatitis B surface Antigen, Hepatitis B core Antibody and Syphilis. A limitation of serological testing is the risk of false negative results due to the dilution of the serum. Hemodilution results from the transfusion of fluids (blood products, colloids and/or crystalloid). Confidence in the accuracy and sensitivity of donor serology testing is of utmost importance to ensure the provision of safe organs and tissues for transplantation.Methods. In order to determine the preferred and validated methodology for determining hemodilution, if any; and to determine the level of hemodilution that jeopardizes serologic test results, we reviewed the literature and current testing practices. Tissue banks throughout Canada as well as accrediting bodies were contacted regarding the hemodilution algorithm they utilize.Results. In the absence of a pretransfusion sample, hemodilution calculations are the prevalent methodology for assessing sensitivity of serology testing. A literature search and personal communications provided no documentation on the validation of any hemodilution algorithm or evidence that 50% hemodilution is an acceptable level for accurate serology testing.Conclusion. A validation of hemodilution algorithms and the acceptable or unacceptable rate of hemodilution is required. The utilization of a validated algorithm should be mandated in standards to ensure continuity of practice by all transplantation centres. If validation cannot be obtained, alternative methodologies for serology testing should be investigated.