Rapid point-of-care detection of SARS-CoV-2 infection in exhaled breath using ion mobility spectrometry: a pilot study.

BACKGROUND: An effective testing strategy is essential for pandemic control of the novel Coronavirus disease 2019 (COVID-19) caused by infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Breath gas analysis can expand the available toolbox for diagnostic tests by using a rapid, cost-beneficial, high-throughput point-of-care test. We conducted a bi-center clinical pilot study in Germany to evaluate breath gas analysis using multi-capillary column ion mobility spectrometry (MCC-IMS) to detect SARS-CoV-2 infection. METHODS: Between September 23, 2020, and June 11, 2021, breath gas measurements were performed on 380 patients (SARS-CoV-2 real-time polymerase chain reaction (PCR) positive: 186; PCR negative: 194) presenting to the emergency department (ED) with respiratory symptoms. RESULTS: Breath gas analysis using MCC-IMS identified 110 peaks; 54 showed statistically significant differences in peak intensity between the SARS-CoV-2 PCR-negative and PCR-positive groups. A decision tree analysis classification resulted in a sensitivity of 83% and specificity of 86%, but limited robustness to dataset changes. Modest values for the sensitivity (74%) and specificity (52%) were obtained using linear discriminant analysis. A systematic search for peaks led to a sensitivity of 77% and specificity of 67%; however, validation by transferability to other data is questionable. CONCLUSIONS: Despite identifying several peaks by MCC-IMS with significant differences in peak intensity between PCR-negative and PCR-positive samples, finding a classification system that allows reliable differentiation between the two groups proved to be difficult. However, with some modifications to the setup, breath gas analysis using MCC-IMS may be a useful diagnostic toolbox for SARS-CoV-2 infection. TRIAL REGISTRATION: This study was registered at ClinicalTrials.gov on September 21, 2020 (NCT04556318; Study-ID: HC-N-H-2004).

PET/MRI-evaluated brown adipose tissue activity may be related to dietary MUFA and omega-6 fatty acids intake.

An investigation of new ways to activate brown adipose tissue (BAT) is highly valuable, as it is a possible tool for obesity prevention and treatment. The aim of our study was to evaluate the relationships between dietary intake and BAT activity. The study group comprised 28 healthy non-smoking males aged 21-42 years. All volunteers underwent a physical examination and 75-g OGTT and completed 3-day food intake diaries to evaluate macronutrients and fatty acid intake. Body composition measurements were assessed using DXA scanning. An FDG-18 PET/MR was performed to visualize BAT activity. Brown adipose tissue was detected in 18 subjects (67% normal-weight individuals and 33% overweight/obese). The presence of BAT corresponded with a lower visceral adipose tissue (VAT) content (p = 0.04, after adjustment for age, daily kcal intake, and DXA Lean mass). We noted significantly lower omega-6 fatty acids (p = 0.03) and MUFA (p = 0.02) intake in subjects with detected BAT activity after adjustment for age, daily average kcal intake, and DXA Lean mass, whereas omega-3 fatty acids intake was comparable between the two groups. BAT presence was positively associated with the concentration of serum IL-6 (p = 0.01) during cold exposure. Our results show that BAT activity may be related to daily omega-6 fatty acids intake.

Clinical diversity and treatment approaches to blastic plasmacytoid dendritic cell neoplasm: a retrospective multicentre study.

BACKGROUND: Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare, aggressive type of haematologic precursor malignancy primarily often manifesting in the skin. We sought to provide a thorough clinical characterization and report our experience on therapeutic approaches to BPDCN. METHODS: In the present multicentric retrospective study, we collected all BPDCN cases occurring between 05/1999 and 03/2018 in 10 secondary care centres of the German-Swiss-Austrian cutaneous lymphoma working group. RESULTS: A total of 37 BPDCN cases were identified and included. Almost 90% of the patients had systemic manifestations (bone marrow, lymph nodes, peripheral blood) in addition to skin involvement. The latter presented with various types of cutaneous lesions: nodular (in more than 2/3) and bruise-like (in 1/3) skin lesions, but also maculopapular exanthema (in circa 1/6). Therapeutically, 22 patients received diverse combinations of chemotherapeutic regimens and/or radiotherapy. Despite initial responses, all of them ultimately relapsed and died from progressive disease. Eleven patients underwent haematopoietic stem cell transplantation (HSCT; autologous HSCT n = 3, allo-HSCT n = 8). The mortality rate among HSCT patients was only 33.33% with a median survival time of 60.5 months. CONCLUSION: Our study demonstrates the clinical diversity of cutaneous BPDCN manifestations and the positive development observed after the introduction of HSCT.

Crystallization of ApoA1 and ApoE4 nanolipoprotein particles and initial XFEL-based structural studies.

Nanolipoprotein particles (NLPs), also called "nanodiscs", are discoidal particles with a patch of lipid bilayer corralled by apolipoproteins. NLPs have long been of interest due to both their utility as membrane-model systems into which membrane proteins can be inserted and solubilized and their physiological role in lipid and cholesterol transport via HDL and LDL maturation, which are important for human health. Serial femtosecond crystallography (SFX) at X-ray free electron lasers (XFELs) is a powerful approach for structural biology of membrane proteins, which are traditionally difficult to crystallize as large single crystals capable of producing high-quality diffraction suitable for structure determination. To facilitate understanding of the specific role of two apolipoprotein/lipid complexes, ApoA1 and ApoE4, in lipid binding and HDL/LDL particle maturation dynamics and develop new SFX methods involving NLP membrane protein encapsulation, we have prepared and crystallized homogeneous populations of ApoA1 and ApoE4 NLPs. Crystallization of empty NLPs yields semi-ordered objects that appear crystalline and give highly anisotropic and diffuse X-ray diffraction, similar in characteristics to fiber diffraction. Several unit cell parameters were approximately determined for both NLPs from these measurements. Thus, low-background, sample conservative methods of delivery are critical. Here we implemented a fixed target sample delivery scheme utilizing the Roadrunner fast-scanning system and ultra-thin polymer/graphene support films, providing a low-volume, low-background approach to membrane protein SFX. This study represents initial steps in obtaining structural information for ApoA1 and ApoE4 NLPs and developing this system as a supporting scaffold for future structural studies of membrane proteins crystalized in a native lipid environment.

[Magnetic resonance imaging and active cardiac implants]. / Magnetresonanztomographie und aktive kardiale Implantate.

The combination of magnetic resonance imaging (MRI) and active cardiac implants, such as pacemakers and implantable cardioverter defibrillators (ICD) has been a challenge for electrophysiologists and imaging for many years. Diagnostic and therapeutic possibilities on the one hand and technical hazards on the other hand highlight the need for improvements and algorithms that enable a safe approach to these challenges. The advent of so-called MRI conditional implants provides safe procedures for at least some of the patients with an implant and the need for MRI. Recently published data encourage clinicians not to completely excluded an imaging modality as promising as MRI in clinically urgent cases in the presence of conventional implants. The interdisciplinary consensus paper of the German Society of Cardiology and the German Society of Radiology provides recommendations for these situations. This review article discusses these recommendations and provides an overview of the most recent publications with a focus on the long-term course of device parameters.

Molecular classification of tumour cells in a patient with intravascular large B-cell lymphoma.

BACKGROUND: Intravascular large B-cell lymphoma (IVLBCL) is a rare type of extranodal LBCL. It is characterized by the proliferation of tumour cells exclusively intraluminally in small blood vessels of different organs. The clinical manifestation depends on the type of organ affected; additionally, a haemophagocytic syndrome can be observed in some patients. OBJECTIVES: The aim was to further understand the nosology of this lymphoma as, due to its rarity and in spite of detailed immunohistochemical investigations, its exact nosology is only incompletely understood. METHODS: We used microarray-based analysis of gene expression of tumour cells isolated from a patient with primary manifestation of the lymphoma in the skin and compared it with various other diffuse LBCLs (DLBCLs) as well as a previously published DLBCL classifier. RESULTS: In unsupervised analyses, the tumour cells clustered together with non-germinal centre B-cell (non-GCB) DLBCL samples but were clearly distinct from GCB-DLBCL. Analogous to non-GCB DLBCL, molecular cell-of-origin classification revealed similarity to bone-marrow derived plasma cells. CONCLUSIONS: The IVLBCL of this patient showed molecular similarity to non-GCB DLBCL. Due to the prognostic and increasingly also therapeutic relevance of molecular subtyping in DLBCL, this method, in addition to immunohistochemistry, should also be considered for the diagnosis of IVLBCL in the future.

Effect of intravenous immunoglobulin administration on erythrocyte and leucocyte parameters.

BACKGROUND: Intravenous immunoglobulins (IVIG) are an attractive therapeutic tool for therapy of toxic epidermal necrolysis and severe forms of certain autoimmune diseases, including dermatomyositis, autoimmune blistering diseases, systemic vasculitis and lupus erythematodes. OBJECTIVES: Prompted by a case of IVIG-associated haemolytic anaemia, the effects of IVIG administrations on haematological parameters in patients with dermatological conditions were investigated. METHODS: Erythrocyte and leucocyte parameters were retrospectively analysed in 16 patients who had received IVIG at doses from 1 to 3 g/kg bodyweight (n = 35 cycles). The influence of IVIG on leucocyte survival was determined in vitro. RESULTS: Decreased absolute erythrocyte numbers, haemoglobin and haematocrit levels and a case of haemolytic anaemia were linked to transfusion of high-, but not low-dose IVIG. In contrast, leucopenia post-IVIG occurred in the vast majority of the recipients, unrelated to the administered IVIG amounts. In vitro investigations revealed a dose-dependent impairment of cell survival by IVIG in the neutrophil and monocyte, but not in the lymphocyte subpopulations. In several IVIG preparations, substantial amounts of blood group anti-A/anti-B antibodies were detected which could have accounted for the observed changes in the haematological parameters in our study cohort. CONCLUSIONS: IVIG products should be administered strictly according to indications. Commercially available IVIG products can contain blood group-specific antibodies that may induce haemolysis in some recipients. Monitoring of blood counts during applied IVIG therapy, especially when high doses are administered, is recommended.

The influence of spatial patterns of capillary networks on transverse relaxation.

Tissue-inherent relaxation parameters offer valuable information about the arrangement of capillaries: in an external field, capillaries act as magnetic perturbers to generate local inhomogeneous fields due to the susceptibility difference of deoxygenated blood and the surrounding tissue. These field inhomogeneities influence the free induction decay in a characteristic way, and, conversely, the above tissue parameters can be recovered by multi-parametric fits of adequate theoretical models to experimentally sampled free induction decays. In this work we study the influence of different spatial patterns of capillary positions on the free induction decay. Starting from the standard single capillary approximation (Krogh cylinder) for a symmetric array of capillaries, the free induction decay is analyzed for increasingly random capillary positions, using a previously described Gibbs point field model. The effects of diffusion are implemented with a flexible and fast random walk simulation. We find that the asymmetric form of the obtained frequency distribution is more robust against variations of capillary radii than against shifts of capillary positions, and further that, for an inclusion of diffusion effects, the single capillary approximation models the uniform alignment of capillaries in the hexagonal lattice to great accuracy. An increase in randomization of capillary positions then leads to a significant change in relaxation times. This effect, however, is found less pronounced than that of changes in the off-resonance field strengths which are controlled by the oxygen extraction fraction, thus indicating that observed changes in BOLD imaging are more likely to be attributed to changes in oxygenation than to capillary alignment.

Optically active P5-deltacyclenes: selective oxidation, ligand properties, and a diastereoselective rearrangement reaction.

Cage-chiral tetra-tert-butyl-P5-deltacyclene is accessible as a pair of highly enriched enantiomers and . The only secondary phosphorus atom P1 of the cage can be selectively oxidized by reaction with t-BuOOH. The P1-oxo species and , allow the direct determination of their ee values. Oxidation occurs with the complete retention of the optical activity of the compounds. The chiroptical properties of and are strongly dominated by their cage chirality, the oxygen atom does not contribute significantly. Elemental sulfur and selenium oxidize P5 with high preference to yield P5-thio- and P5-seleno-P5-deltacyclenes and of the intact cages again. Longer reaction time and more than stoichiometric amounts of selenium, leads to tri-seleno-P5-tetracycloundecane , a partially opened oxidized rearrangement product. The ligand properties of racemic were determined. Diphosphetane phosphorus atom P2 of is the active donor center to bind a Cr(CO)5 fragment, but a tautomerization of takes place if [(benzene)RuCl2]2 is added. A hydrogen atom migrates from P1 to the oxygen atom to form a phosphinous acid ligand. The lone pair of P1 is regenerated and acts as the active ligand function of the cage in this case. As for , the base n-BuLi induces an efficient cage rearrangement reaction of , where P1 and the neighboring carbon atom C4 containing its t-Bu substituent change places. C4 moves to its new position without breaking the bond with P5, this way forming the novel P1-oxo-P5-norsnoutene cage in a highly diastereoselective process.

The changing face of internal medicine: patient centred care.

Patient centred care is now considered the gold standard and there should be 'no decision about me, without me'. Internists who treat patients with complex multi-morbidities should consider patients' preferred outcomes, following a 'goal-oriented' principle. Perhaps the most important barrier to goal-oriented care is that medicine is deeply rooted in a disease-outcome-based paradigm. Rather than asking what patients want, the culture of modern medicine has prioritised optimal disease management according to guidelines and population goals. Doing what is right for the patient should be based on trust. Patients and internists must therefore meet as equals: 'I' and 'you' should be replaced by 'we'.

Case series evidence for changed interhemispheric relationships in cortical structure in some amputees.

Limb amputation and related changes in body feelings are associated with cortical functional reorganization that is reflected by increased interhemispheric asymmetry of body maps in the postcentral somatosensory cortex (PCS). As a pilot test to determine if limb amputation affects interhemispheric symmetry in PCS structure, we used MRI and computational morphometry to examine interhemispheric relationships of PCS thicknesses in a case series of eight lower limb amputees compared with 11 control subjects. As a further control, the same relationships were compared in the lateral occipital visual cortex (LOV) which, by nature of its visual connectivity, would be expected to be less related to amputation. The PCS thicknesses in the left and right hemispheres were positively related in control subjects, but not in amputees. The range of the PCS interhemispheric thickness differences (ID) in amputees was larger than the range in control subjects, and four of eight amputees had PCS ID that were at or above the maximal control subject ID. In contrast, LOV thicknesses in the two hemispheres were positively related and LOV ID ranges were similar in both amputees and control subjects. The results from this case series suggest the hypothesis that amputation alters PCS interhemispheric thickness relationships in some amputees. Further tests of this hypothesis would be useful to determine whether changes in structural symmetry contribute to known post-amputation alterations in PCS functional map symmetry and body feeling.

Spin dephasing in a magnetic dipole field.

Transverse relaxation by dephasing in an inhomogeneous field is a general mechanism in physics, for example, in semiconductor physics, muon spectroscopy, or nuclear magnetic resonance. In magnetic resonance imaging the transverse relaxation provides information on the properties of several biological tissues. Since the dipole field is the most important part of the multipole expansion of the local inhomogeneous field, dephasing in a dipole field is highly important in relaxation theory. However, there have been no analytical solutions which describe the dephasing in a magnetic dipole field. In this work we give a complete analytical solution for the dephasing in a magnetic dipole field which is valid over the whole dynamic range.

[Treatment of stress urinary incontinence after radical prostatectomy: adjustable transobturator male system - results of a multicenter prospective observational study]. / Behandlung der Belastungsinkontinenz nach radikaler Prostatektomie : Adjustierbares transobturatorisches System - prospektive multizentrische Anwendungsbeobachtung.

BACKGROUND: The adjustable transobturator male system (ATOMS®) is a new method for the treatment of male stress urinary incontinence. This article presents the results of a prospective multicenter observational study with this system. PATIENTS AND METHODS: Between March 2009 and March 2011 a total of 124 patients with persistent stress urinary incontinence after radical prostatectomy received the ATOMS system. Postoperative adjustments via the implanted port chamber were performed after 6 weeks and thereafter when necessary. Postoperative evaluation consisted of medical history, mictionary protocol, 24-h pad tests, 24-h pad counts and sonography. RESULTS: The mean age of the patients was 71.2 ± 5.5 years (range 58-85 years). Previous incontinence surgery had been carried out in 36.3% of patients while 34.5% of patients had a previous history of radiation treatment. The mean operation time was 48.3 ± 11.2 min (range 36-116 min) and the mean hospital stay was 3.8 ± 1.2 days (range 2-6 days). No intraoperative urethral or bladder injuries occurred. After removal of the transurethral catheter on the first postoperative day, temporary urinary retention occurred in 3 patients who were conservatively treated. Transient perineal/scrotal pain or dysesthesia was observed in 75 patients (60.5%) and resolved after 3-4 weeks of non-opioid analgesics. There were no perineal infections; however, infections at the port site occurred in 3 patients (2.4%) leading to explantation of the system in all cases. The average number of adjustments to achieve the desired result was 4.3 ± 1.8 (range 2-7). After a mean follow-up of 19.1 ± 2.2 months (range 12-36 months), there was a significant reduction in the mean number of pads/24 h from 8.8 to 1.8 (p<0.001). The overall success rate was 93.8% with 61.6% of the patients being dry and 32.2% of the patients showing improvement. CONCLUSIONS: The results of the study demonstrate the safety and efficacy to date of the ATOMS system for treatment of stress urinary incontinence after radical prostatectomy.

MR safety: fast T1 thermometry of the RF-induced heating of medical devices.

Determining the MR compatibility of medical implants and devices is becoming increasingly relevant. In most cases, the heating of conductive implants due to radiefrequency (RF) excitation pulses is measured by fluoroptic temperature sensors in relevant tests for approval. Another common method to determine these heating effects is MR thermometry using the proton resonance frequency. This method gives good results in homogeneous phantoms. However in many cases, technical shortcomings such as susceptibility artifacts prohibit exact proton resonance frequency thermometry near medical implants. Therefore, this work aimed at developing a fast T1-based method which allows controlled MR-related heating of a medical implant while simultaneously quantifying the spatial and temporal temperature distribution. To this end, an inversion recovery snapshot Fast Low-Angle Shot (FLASH) sequence was modified with additional off-resonant heating pulses. With an accelerated imaging method and a sliding-window technique, every 7.6 s a new temperature map could be generated with a spatial in-plane resolution of 2 mm. The temperature deviation from calculated temperature values to reference fluoroptic probe was found to be smaller than 1 K.

Automated serial sectioning applied to 3D paper structure analysis.

A better understanding of paper properties requires a detailed knowledge about the spatial arrangement of its constituent materials in its structure. This paper presents a novel approach for the analysis of the three-dimensional paper structure at the fibre level. A technique combining a rotary microtome and an optical microscopy was developed allowing serial sectioning of hundreds of cuts. The microscope is fixed on a moveable stage and mounted in front of a microtome. Repeatedly, thin slices are cut off an embedded paper sample and the cut block surface is scanned in a fully automated process. The prototype built is able to digitize paper samples with a size of more than 1 cm(2) at a possible three-dimensional resolution below 1 µm. Advanced computer vision methods are applied to extract relevant information from the digitized samples. Currently, the most important applications are the analysis of pigment coating layers on the paper surfaces and the analysis of fibre transverse morphology. Besides the analysis of paper structures, this technique is also suited for the spatial analysis of other materials, if the structural features are accessible with light optical microscopy.

Application of compressed sensing to in vivo 3D ¹9F CSI.

This study shows how applying compressed sensing (CS) to (19)F chemical shift imaging (CSI) makes highly accurate and reproducible reconstructions from undersampled datasets possible. The missing background signal in (19)F CSI provides the required sparsity needed for application of CS. Simulations were performed to test the influence of different CS-related parameters on reconstruction quality. To test the proposed method on a realistic signal distribution, the simulation results were validated by ex vivo experiments. Additionally, undersampled in vivo 3D CSI mouse datasets were successfully reconstructed using CS. The study results suggest that CS can be used to accurately and reproducibly reconstruct undersampled (19)F spectroscopic datasets. Thus, the scanning time of in vivo(19)F CSI experiments can be significantly reduced while preserving the ability to distinguish between different (19)F markers. The gain in scan time provides high flexibility in adjusting measurement parameters. These features make this technique a useful tool for multiple biological and medical applications.

Endometrial effects of exemestane compared to tamoxifen within the Tamoxifen Exemestane Adjuvant Multicenter (TEAM) trial: results of a prospective gynecological ultrasound substudy.

OBJECTIVES: This study prospectively assessed the effects of exemestane and tamoxifen on the endometrium in patients receiving adjuvant treatment for postmenopausal hormone receptor-positive breast cancer within the Tamoxifen Exemestane Adjuvant Multicenter (TEAM) trial. METHODS: Patients were randomized to receive tamoxifen or exemestane. In a prespecified trial subprotocol, patients underwent transvaginal ultrasound to assess endometrial thickness at baseline and during a 1- to 3-year treatment period. RESULTS: Among 143 evaluable patients, there were no cases of endometrial thickness >10 mm with exemestane, vs. 11 cases with tamoxifen (p < 0.0003). There was a significant difference between the treatment groups regarding time to endometrial thickness >10mm, in favour of exemestane (p < 0.0001). Time to endometrial thickness > 5 mm was significantly longer for exemestane than for tamoxifen (p < 0.0001). Median time to endometrial thickness > 5 mm or censoring was 583 days in the exemestane group versus 315 days in the tamoxifen group. There were also significantly fewer incidences of endometrial thickness > 5 mm at month 6 and month 12 with exemestane compared to tamoxifen (tamoxifen: 6% and 2%; exemestane: 29% and 39%, respectively). After 12 months, mean increases in endometrial thickness from baseline were 2.64 mm and 6.0mm in the exemestane and tamoxifen groups, respectively (p < 0.0006). Moreover, 17 histologically confirmed endometrial changes were observed in the tamoxifen group, vs. one in the exemestane group. CONCLUSIONS: Exemestane was associated with significantly less endometrial thickening than tamoxifen during adjuvant endocrine therapy for postmenopausal hormone receptor-positive breast cancer.

First-line therapy with moderate dose capecitabine in metastatic breast cancer is safe and active: results of the MONICA trial.

BACKGROUND: To determine activity and safety of capecitabine at a moderate dose of 2000 mg/m(2) as first-line therapy for metastatic breast cancer. METHODS: In this prospective phase II trial, patients with HER2-negative metastatic breast cancer received first-line capecitabine 2000 mg/m(2) on days 1-14 every 3 weeks. The primary aim was to exclude a time to progression (TTP) <6 months. Secondary end-points were overall response rate, overall survival (OS), toxicity and quality of life. RESULTS: Median age of the 161 included patients was 65 years. Median TTP and OS were 7.3 months [95% (confidence interval) CI: 6.2-8.4] and 17.1 months (95% CI: 14.0-20.3), respectively. An overall response rate of 26.1%, including 13 complete remissions was observed. Patients developing grade I-III hand-foot syndrome had a significantly longer TTP and OS and patients >65 years also achieved a significantly longer TTP. Haematological grade I-IV toxicities were leucopenia (64.0%), anaemia (50.9%) and thrombocytopenia (28.0%). Relevant non-haematological toxicities were hand-food-syndrome (37.3%), fatigue (34.2%), nausea (29.8%) and diarrhoea (20.5%). Quality of life assessment revealed an improved emotional function, but worsening of nausea and vomiting from cycle 1-10. CONCLUSIONS: Capecitabine at a dose of 2000 mg/m(2) is active and safe as first-line treatment of patients with metastatic breast cancer.