High Temperature Electron Diffraction on Organic Crystals: In Situ Crystal Structure Determination of Pigment Orange 34

Small molecule structures and their applications rely on good knowledge of their atomic arrangements. However, the crystal structures of these compounds and materials, which are often composed of fine crystalline domains, cannot be determined with single-crystal X-ray diffraction. Three-dimensional electron diffraction (3D ED) is already becoming a reliable method for the structure analysis of submicrometer-sized organic materials. The reduction of electron beam damage is essential for successful structure determination and often prevents the analysis of organic materials at room temperature, not to mention high temperature studies. In this work, we apply advanced 3D ED methods at different temperatures enabling the accurate structure determination of two phases of Pigment Orange 34 (C34H28N8O2Cl2), a biphenyl pyrazolone pigment that has been industrially produced for more than 80 years and used for plastics application. The crystal structure of the high-temperature phase, which can be formed during plastic coloration, was determined at 220 °C. For the first time, we were able to observe a reversible phase transition in an industrial organic pigment in the solid state, even with atomic resolution, despite crystallites being submicrometer in size. By localizing hydrogen atoms, we were even able to detect the tautomeric state of the molecules at different temperatures. This demonstrates that precise, fast, and low-dose 3D ED measurements enable high-temperature studies the door for general in situ studies of nanocrystalline materials at the atomic level.

Structural analysis of potato starch transformation during high-energy ball-milling: Oxygen and humidity content effects

High Energy Ball-Milling (HEBM) modifies starchs' granule morphology, physicochemical properties, and chemical structure. However, understanding how the HEBM changes the starch chemical structure is necessary to control these modifications. Therefore, this study aimed to investigate the changes in potato starch's long- and short-range molecular order during HEBM at different environmental conditions such as oxygen (Air) and humidity content. Due to the correlation between the starch modification and the energy supplied (Esupp) by the HEBM, Burgio's equation was used to calculate this energy. The starch transformation was followed by X-ray diffraction, Fourier Transform-Infrared Spectroscopy, and Raman spectroscopy. A Principal Component Analysis (PCA) was conducted to reduce the HEBM variables. PAC analysis demonstrated that the different oxygen-humidity conditions do not affect the HEBM of potato starch. Based on the starch chemical structure transformation correlated with Esupp during HEBM, four stages were observed: orientation, modification, mechanolysis, and over-destruction. It was identified for the first time that at low milling energy (<1.5 kJ/g, orientation stage), the glycosidic rings change their orientation, and starch-water interaction increases while the starch's organization reduces. Ergo, the potato starch could be more susceptible to chemical modifications during the first two stages.

1350 “TO BE A DEMENTIA-FRIENDLY HOSPITAL, I THINK YOU NEED TO HAVE…” - THE PERSPECTIVES OF PROFESSIONAL DEMENTIA EXPERTS

Introduction

Dementia-friendly hospitals (DFH) are mentioned as one of several key initiatives in national dementia strategies. In our previous integrative review, we identified 17 descriptions of DFHs and analysed six characteristics of DFH: continuity, person-centredness, consideration of phenomena within dementia, environment, valuing relatives and knowledge and expertise within the hospital (Manietta, Purwins, Reinhard et al., BMC Geriatrics, 2022, 22, 468, 1-16). We also learned that the term DFH is based more on healthcare practice than research. To address this research gap, one step of our DEMfriendlyHospital study is to examine the perspectives of professional dementia experts working in hospitals in Germany.

Method

We used a qualitative design and conducted 14 semi-structured interviews with professional dementia experts from various healthcare professions (12 nurses, two physicians, and one physiotherapist). Data were collected between November 2021 and March 2022. Using an inductive content analysis, we furthermore analysed the interviews in a participatory way involving a group of research associates and professional dementia experts.

Results

From the professional dementia experts’ perspectives, a DFH is characterised by specific hospital processes, structures and environment which consider the needs of people with dementia, dementia-specific knowledge and the skills of hospital staff, their awareness and attitude towards people with dementia. A DFH needs the social inclusion of patients with dementia and their perception as a person as well as the involvement of relatives, who are an important support for the patients and their care.

Conclusion

There are links between our results from interviews with professional dementia experts and our integrative review. At the same time, the perspectives of patients with dementia and their relatives are underrepresented. To fill this gap, our next step is to interview people with dementia who are hospitalised and their relatives, aiming to enhance the description of a DFH and its characteristics.

Solid-State NMR-Driven Crystal Structure Prediction of Molecular Crystals: The Case of Mebendazole

Among all possible NMR crystallography approaches for crystal-structure determination, crystal structure prediction - NMR crystallography (CSP-NMRX) has recently turned out to be a powerful method. In the latter, the original procedure exploited solid-state NMR (SSNMR) information during the final steps of the prediction. In particular, it used the comparison of computed and experimental chemical shifts for the selection of the correct crystal packing. Still, the prediction procedure, generally carried out with DFT methods, may require important computational resources and be quite time-consuming, especially if there are no available constraints to use at the initial stage. Herein, the successful application of this combined prediction method, which exploits NMR information also in the input step to reduce the search space of the predictive algorithm, is presented. Herein, this method was applied on mebendazole, which is characterized by desmotropism. The use of SSNMR data as constraints for the selection of the right tautomer and the determination of the number of independent molecules in the unit cell led to a considerably faster process, reducing the number of calculations to be performed. In this way, the crystal packing was successfully predicted for the three known phases of mebendazole. To evaluate the quality of the predicted structures, these were compared to the experimental ones. The crystal structure of phase B of mebendazole, in particular, was determined de novo by powder diffraction and is presented for the first time in this paper.

Sustained-release hot melt extrudates of the weak acid TMP-001: A case study using PBB modelling

Over the last 30 years, hot melt extrusion has become a leading technology in the manufacture of amorphous drug delivery systems. Mostly applied as an 'enabling formulation' for poorly soluble compounds, application in the design of sustained-release formulations increasingly attracts the attention of the pharmaceutical industry. The drug candidate TMP-001 is currently under evaluation for the early treatment of Multiple Sclerosis. Although this weak acid falls into class II of the Biopharmaceutics Classification System, the compound exhibits high solubility in the upper intestine resulting in high peroral bioavailability. In the present studies, four different formulation prototypes varying in their sustained-release behavior were developed, using L-arginine as a pore-forming agent in concentrations ranging between 0 and 20%. Initially, biorelevant release testing was applied to assess the dissolution behavior of the prototypes. For these formulations, a total drug release of 44.7%, 64.6%, 75%, and 90.5% was achieved in FaSSIF-v2 after 24 h. Two candidates were selected for further characterization considering the crystal structure and the physical stability of the amorphous state of TMP-001 in the formulations together with the release behavior in Level II biorelevant media. Our findings indicate L-arginine as a valuable excipient in the formulation of hot melt extrudates, as its presence led to a considerable stabilization of the amorphous state and favorably impacted the milling process and release behavior of TMP-001. To properly evaluate the proposed formulations and the importance of colonic dissolution and absorption on the overall bioavailability, a physiologically-based biopharmaceutics model was used.

[German Guideline for Idiopathic Pulmonary Fibrosis]

Idiopathic pulmonary fibrosis (IPF) is a severe and often fatal disease. Diagnosis of IPF requires considerable expertise and experience. Since publication of the international IPF guideline in the year 2011 and Update 2018 several studies and technical advances occurred, which made a new assessment of the diagnostic process mandatory. In view of the antifibrotic drugs which have been approved for the treatment of IPF patients, the goal of this guideline is to foster early, confident and effective diagnosis of IPF. The guideline focusses on the typical clinical setting of an IPF patient and provides tools to exclude known causes of interstitial lung disease including standardised questionnaires, serologic testing and cellular analysis of bronchoalveolar lavage. High resolution computed tomography remains crucial in the diagnostic work-up. If it is necessary to obtain specimen for histology transbronchial lung cryobiopsy is the primary approach, while surgical lung biopsy is reserved for patients who are fit for it and in whom bronchoscopic diagnosis did not provide the information needed. Despite considerable progress, IPF remains a diagnosis of exclusion and multidisciplinary discussion remains the golden standard of diagnosis.

4-Cyanopyridine complexes [MX2(4-CNpy)x]n (with X = Cl, Br and x = 1, 2): crystal structures, thermal properties and a comparison with [MX2(3-CNpy)x]n complexes

Crystal structures of [MX₂(4-CNpy)_x] with X = Cl and Br, M = Mn, Fe, Co, Ni, Cu, and Zn, and x = 1 and 2 were determined by X-ray powder diffraction. 4-Cyanopyridine can build chain and net structures.

[Immunophenotyping of lung tumors : An update]

The WHO Classification of Lung Tumors (2015) established the use of immunohistochemical stainings for resection specimens, however, detailed recommendations had been missing. Now, an international expert panel has summarized key questions for daily routine practice and provided recommendations to assist the community in the appropriate use of immunohistochemistry in this context. This article provides an overview of the most important aspects.

Synthesis and structure of the donor-free potassium silanide K[SiPh3]

The donor-free potassium silanide K[SiPh3] was prepared by the reaction of hexaphenyldisilane, Ph3Si–SiPh3, with potassium metal in benzene at room temperature. The solid-state structure, determined by powder X-ray diffraction consists of {K[SiPh3]}2units, which interact with adjacent dimers to form an infinite chain along the crystallographiccaxis (orthorhombic, space groupCmc21,Z=4). The structure features short contacts between the π system of the phenyl rings and the potassium atoms of neighbouring K[SiPh3] units.

Coordination compounds built up from MIICl2 and 3-cyanopyridine: double chains, single chains and isolated complexes

Crystal structures of [M^IICl₂(3-CNpy)_x], with M = Mn, Fe, Co, Ni, Cu, Zn and x = 1, 2, were determined by X-ray powder diffraction. Surprisingly, 3-cyanopyridine coordinates monodentately only.

Electron diffraction tomography and X-ray powder diffraction on photoredox catalyst PDI

The crystal structure of photoredox catalyst PDI-iPr was determined by a combination of electron diffraction tomography and XRPD.

Syntheses and Crystal Structures of Phenyl-Lithium Derivatives

Although organolithium compounds have been studied and applied for ∼100 years, only few crystal structures of pure, unsolvated organolithium compounds have been reported so far. Therefore, several phenyl-lithium derivatives were synthesized by lithium-halogen exchange reactions, yielding fairly soluble polymers in the cases of 4- and 2-methylphenyl-lithium ( p-TolLi and o-TolLi). Their crystal structures have been determined by X-ray powder diffraction. Remarkably, o-TolLi crystallizes in the noncentrosymmetric space group P2₁2₁2₁ with two independent monomers, whereas the crystal structure of p-TolLi is described in spacegroup P2₁/ a. In contrast, no polymer of 5- m-XyLi (3,5-dimethyl-phenyl-lithium) could be observed, but single crystals of a [(5- m-XyLi)₃(MTBE)₃LiBr] adduct were isolated (MTBE = methyl- tert-butylether). This gives hints on the nature of lithium-halogen exchange reactions. Steric and electronic effects of the phenyl-lithium substitution are further discussed in conjunction with related compounds.

The association between the patient and the physician genders and the likelihood of intensive care unit admission in hospital with restricted ICU bed capacity

BACKGROUND

Despite the evidence that the patient gender is an important component in the intensive care unit (ICU) admission decision, the role of physician gender and the interaction between the two remain unclear.

OBJECTIVE

To investigate the association of both the patient and the physician gender with ICU admission rate of critically ill emergency department (ED) medical patients in a hospital with restricted ICU bed capacity operates with 'closed door' policy.

METHODS

A retrospective population-based cohort analysis. We included patients above 18 admitted to an ED resuscitation room (RR) of a tertiary hospital during 2011-12. Data on medical, laboratory and clinical characteristics were obtained. We used an adjusted multivariable logistic regression to analyze the association between both the patient and the physician gender to the ICU admission decision.

RESULTS

We included 831 RR admissions, 388 (46.7%) were female patients and 188 (22.6%) were treated by a female physicians. In adjusted multivariable analysis (adjusted for age, diabetes, mode of hospital transportation, first pH and patients who were treated with definitive airway and vasso-pressors in the RR), female-female combination (patient-physician, respectively) showed the lowest likelihood to be admitted to ICU (adjusted OR: 0.21; 95% CI: 0.09-0.51) compared to male-male combination, in addition to a smaller decrease among female-male (adjusted OR: 0.53; 95% CI: 0.32-0.86) and male-female (adjusted OR: 0.43; 95% CI: 0.21-0.89) combinations.

CONCLUSION

We demonstrated the existence of the possible gender bias where female gender of the patient and treating physician diminish the likelihood of the restricted health resource use.

Sample Selection for Microarray Gene Expression Studies

Objectives: The choice of biomedical samples for microarray gene expression studies is decisive for both validity and interpretability of results. We present a consistent, comprehensive framework to deal with the typical selection problems in microarray studies.

Methods: Microarray studies are designed either as case-control studies or as comparisons of parallel groups from cohort studies, since high levels of random variation in the experimental approach thwart absolute measurements of gene expression levels. Validity and results of gene expression studies heavily rely on the appropriate choice of these study groups. Therefore, the so-called principles of comparability, which are well known from both clinical and epidemiological studies, need to be applied to microarray experiments.

Results: The principles of comparability are the study-base principle, the principle of deconfounding and the principle of comparable accuracy in measurements. We explain each of these principles, show how they apply to microarray experiments, and illustrate them with examples. The examples are chosen as to represent typical stumbling blocks of microarray experimental design, and to exemplify the benefits of implementing the principles of comparability in the setting of micro-array experiments.

Conclusions: Microarray studies are closely related to classical study designs and therefore have to obey the same principles of comparability as these. Their validity should not be compromised by selection, confounding or information bias. The so-called study-base principle, calling for comparability and thorough definition of the compared cell populations, is the key principle for the choice of biomedical samples and controls in microarray studies.

3-Cyanopyridine as a bridging and terminal ligand in coordination polymers

Crystal structures of [M^IIBr₂(3-CNpy)_x]_(n) with M = Mn, Fe, Co, Ni and x = 1, 2, 4 were determined by powder diffraction. For x = 1, the 3-cyanopyridine ligand is bridging two metal atoms.

Crystal structures of ordered and plastic-crystalline phases of iso-butyllithium by X-ray powder diffraction

The crystal structures of solid, donor-free i-BuLi at different temperatures were determined from X-ray powder diffraction data.

Cast wedging: a systematic review of the present evidence

PURPOSE

The objective of this systematic review was to summarise the outcome after cast wedging due to loss of angulation in conservative fracture treatment of children's fractures.

METHODS

Electronic searches were performed using MEDLINE, PubMed, OVID, CENTRAL and EMBASE without language restrictions.

RESULTS

Three studies comprising 316 patients (210 radius, 52 forearm/both bone forearm fractures and 54 tibia fractures) were included in the present analysis. Cast wedge failures occurred in 14 of 316 (4.4%) patients. Three patients (0.9%) needed surgical fixation and 11 patients (3.4%) ended up with a healed deformity. Furthermore, eight of 316 (1.8%) patients needed remanipulation and cast change.

CONCLUSION

Cast wedging reflects a reliable treatment option for secondary displaced long-bone paediatric fractures.

A Multinational Analysis of Mutations and Heterogeneity in PZase, RpsA, and PanD Associated with Pyrazinamide Resistance in M/XDR Mycobacterium tuberculosis

Pyrazinamide (PZA) is an important first-line drug in all existing and new tuberculosis (TB) treatment regimens. PZA-resistance in M. tuberculosis is increasing, especially among M/XDR cases. Noted issues with PZA Drug Susceptibility Testing (DST) have driven the search for alternative tests. This study provides a comprehensive assessment of PZA molecular diagnostics in M/XDR TB cases. A set of 296, mostly XDR, clinical M. tuberculosis isolates from four countries were subjected to DST for eight drugs, confirmatory Wayne's assay, and whole-genome sequencing. Three genes implicated in PZA resistance, pncA, rpsA, and panD were investigated. Assuming all non-synonymous mutations cause resistance, we report 90% sensitivity and 65% specificity for a pncA-based molecular test. The addition of rpsA and panD potentially provides 2% increase in sensitivity. Molecular heterogeneity in pncA was associated with resistance and should be evaluated as a diagnostic tool. Mutations near the N-terminus and C-terminus of PZase were associated with East-Asian and Euro-American lineages, respectively. Finally, Euro-American isolates are most likely to have a wild-type PZase and escape molecular detection. Overall, the 8-10% resistance without markers may point to alternative mechanisms of resistance. Confirmatory mutagenesis may improve the disconcertingly low specificity but reduce sensitivity since not all mutations may cause resistance.

[The new TNM classification for lung tumors : Changes and the assessment of multiple tumor foci]

Recently a new TNM classification for tumors of the lung was published, encompassing some relevant changes, for example how to deal with multiple lung tumors. This article comprehensively describes respective changes. Furthermore, background information on how the new TNM classification was built and what should be done in the future to further improve prognosis and outcome prediction is reviewed.

4-Cyanopyridine, a versatile mono- and bidentate ligand. Crystal structures of related coordination polymers determined by X-ray powder diffraction

4-Cyanopyridine (4-CNpy) as a monodentate ligand in single or double chains or as a bidentate ligand in two-dimensional networks.

Syntheses and structures of two [Au(I)PPh3]-complexes with 2-aceneoxazolethiolates as ligands

The crystal structures of two thiolato complexes of the type [Au(SR)(PPh3)] with SR=2-mercaptobenzoxazol-2-yl (MBOx) and SR=2-mercaptoanthraceneoxazol-2-yl (MAOx) were determined from X-ray powder diffraction data. Both complexes include η1-S-monodentate ligands with the nitrogen atom preferably oriented towards the gold atom. [Au(MBOx)(PPh3)] (1a) represents a new triclinic polymorph of [Au(MBOx)(PPh3)], whereas [Au(MAOx)(PPh3)] (2) is hitherto unknown and yields information about the molecular structure of the ligand MAOx as well as the coordination geometry in 2. The structure determinations were validated by low temperature XRPD measurements. DTA-TG and in-situ XRPD measurements revealed a monotropic phase transition of 1a at 443 K to a monoclinic phase. Additionally, solid-state DFT-D calculations using CASTEP were carried out to evaluate the experimental results.

[Multifocal Pulmonary Neuroendocrine Tumours: Genesis, Diagnostics and Treatment]

Multifocal neuroendocrine lung tumour is a rare diagnosis. Multiple lung foci of different sizes are usually apparent on chest CT scans. It is assumed that multifocal neuroendocrine lung tumours originally develop from diffuse idiopathic pulmonary neuroendocrine cell hyperplasia (DIPNECH). This results in cell aggregations formed by proliferation of neuroendocrine cells that are already physiologically present in the bronchial system. If these cell proliferations break through the bronchial basement membrane, they are considered to constitute tumourlets if they measure ≤ 5 mm and carcinoid tumours if they are larger than 5 mm. The speed of proliferation of the cell hyperplasias appears to vary. Many of the patients are completely asymptomatic, the multifocal neuroendocrine lung tumours being diagnosed by chance. However, other patients complain of breathlessness, reduced physical capacity and cough. There may also be reduction of lung function. In these cases, chest HRCT often reveals peribronchial fibrosis or bronchiectasis in addition to the lung foci. Bronchoscopy is usually not helpful. Surgical lung biopsy is considered to be the diagnostic gold standard. Histological examination typically shows a mixture of cell hyperplasias, tumourlets and carcinoid tumours. There is no consensus on the treatment of multifocal neuroendocrine tumours. Taking the clinical situation and the chest HRCT findings as our starting point, we developed a stepwise approach that is guided by the success of the individual therapeutic procedures. The most favourable prognosis is found in affected people without clinical symptoms whose lung foci all measure less than 5 mm. In these cases the 5-year survival rate is over 90%.

PDF calculations from STOE STADI P Ag Kα1 low- and high-temperature data

An impressive comparison of G(r) calculated with PDFgetX2(1) from data of Naphthalen taken at room temperature with a Stoe Stadi P powder diffractometer in Transmission mode equipped with a Ag-tube, a Ge(111)-monochromator for pure Ag-Kα1-radiation (0.5594 Å) as well as the Dectris MYTHEN 1K with1mm chip size and from synchrotron data, beamline X17A, NSLS Brookhaven with a wavelength of 0.1839 Å, yields amazingly similar peak widths for both experiment sites. To observe the temperature dependence of this resolution, the same laboratory setup with an additional Oxford Cryosystems Cobra or a Stoe furnace has been chosen to compare the signal width as a function of T. Low temperature data for these PDF calculation experiments has been taken from LaB6 as a crystalline standard and Naphthalene as well known organic phase. In addition high temperature G(r)-data from Ammonium Nitride will be demonstrated.