Direct Transition from Ultrathin Orthorhombic Dinickel Silicides to Epitaxial Nickel Disilicide Revealed by In Situ Synthesis and Analysis.

Understanding phase transitions of ultrathin metal silicides is crucial for the development of nanoscale silicon devices. Here, the phase transition of ultrathin (3.6 nm) Ni silicides on Si(100) substrates is investigated using an in situ synthesis and characterization approach, supplemented with ex situ transmission electron microscopy and nano-beam electron diffraction. First, an ultrathin epitaxial layer and ordered structures at the interface are observed upon room-temperature deposition. At 290 °C, this structure is followed by formation of an orthorhombic δ-Ni2 Si phase exhibiting long-range order and extending to the whole film thickness. An unprecedented direct transition from this δ-Ni2 Si phase to the final NiSi2- x phase is observed at 290 °C, skipping the intermediate monosilicide phase. Additionally, the NiSi2- x phase is found epitaxial on the substrate. This transition process substantially differs from observations for thicker films. Furthermore, considering previous studies, the long-range ordered orthorhombic δ-Ni2 Si phase is suggested to occur regardless of the initial Ni thickness. The thickness of this ordered δ-Ni2 Si layer is, however, limited due to the competition of different orientations of the δ-Ni2 Si crystal. Whether the formed δ-Ni2 Si layer consumes all deposited nickel is expected to determine whether the monosilicide phase appears before the transition to the final NiSi2- x phase.

[Management of COVID-19 mass casualty incidents in nursing and retirement homes]. / Managementstrategie für den Massenanfall von Erkrankten/Infizierten in Alten- und Pflegeheimen im Kontext der COVID-19-Pandemie.

BACKGROUND: During the coronavirus disease 2019 (COVID-19) pandemic, outbreaks in inpatient care facilities, which grow into a large-scale emergency scenario, are frequently observed. A standardized procedure analogous to algorithms for mass casualty incidents (MCI) is lacking. METHODS: Based on a case report and the literature, the authors present a management strategy for infectious MCI during the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic and distinguish it from traumatic MCI deployment tactics. RESULTS: This management strategy can be divided into three phases, beginning with the acute emergency response including triage, stabilization of critical patients, and transport of patients requiring hospitalization. Phase 2 involves securing the facility's operational readiness, or housing residents elsewhere in case staff are infected or quarantined to a relevant degree. Phase 3 marks the return to regular operations. DISCUSSION: Phase 1 is based on usual MCI principles, phase 2 on hospital crisis management. Avoiding evacuation of residents to relieve hospitals is an important operational objective. The lack of mission and training experience with such situations, the limited applicability of established triage algorithms, and the need to coordinate a large number of participants pose challenges. CONCLUSION: This strategic model offers a practical, holistic approach to the management of infectious mass casualty scenarios in nursing facilities.

Phosphocholine-Modified Lipooligosaccharides of Haemophilus influenzae Inhibit ATP-Induced IL-1ß Release by Pulmonary Epithelial Cells.

Phosphocholine-modified bacterial cell wall components are virulence factors enabling immune evasion and permanent colonization of the mammalian host, by mechanisms that are poorly understood. Recently, we demonstrated that free phosphocholine (PC) and PC-modified lipooligosaccharides (PC-LOS) from Haemophilus influenzae, an opportunistic pathogen of the upper and lower airways, function as unconventional nicotinic agonists and efficiently inhibit the ATP-induced release of monocytic IL-1ß. We hypothesize that H. influenzae PC-LOS exert similar effects on pulmonary epithelial cells and on the complex lung tissue. The human lung carcinoma-derived epithelial cell lines A549 and Calu-3 were primed with lipopolysaccharide from Escherichia coli followed by stimulation with ATP in the presence or absence of PC or PC-LOS or LOS devoid of PC. The involvement of nicotinic acetylcholine receptors was tested using specific antagonists. We demonstrate that PC and PC-LOS efficiently inhibit ATP-mediated IL-1ß release by A549 and Calu-3 cells via nicotinic acetylcholine receptors containing subunits α7, α9, and/or α10. Primed precision-cut lung slices behaved similarly. We conclude that H. influenzae hijacked an endogenous anti-inflammatory cholinergic control mechanism of the lung to evade innate immune responses of the host. These findings may pave the way towards a host-centered antibiotic treatment of chronic airway infections with H. influenzae.

Impact of Green Tea Catechin ECG and Its Synthesized Fluorinated Analogue on Prostate Cancer Cells and Stimulated Immunocompetent Cells.

Among the known or suspected risk factors, inflammation plays an important role in infectious and non-infectious pathways leading to cancer. Green tea polyphenols have been associated with reducing inflammation and protection against carcinogenesis, especially in prostate cancer. While most of the research in this field, so far, has focussed on epigallocatechin-3-O-gallate only, we studied epicatechin-3-O-gallate, the second most abundant green tea polyphenol with essential therapeutic potential, to obtain a more detailed understanding of its anti-tumor and anti-inflammatory action. Furthermore, to improve the bioactivity of (-)-epicatechin-3-O-gallate, we synthesized a difluoro analogue, called (-)-5,7-difluoro-epicatechin-3-O-gallate. Both compounds reduced cell proliferation of human primary inflammatory lymphocytes in an apoptosis-specific fashion, while (-)-5,7-difluoro-epicatechin-3-O-gallate had a significantly higher activity compared to the natural product (-)-epicatechin-3-O-gallate. Treatment of low-metastatic LNCaP and high-metastatic PC-3 prostate cancer cells with (-)-epicatechin-3-O-gallate and (-)-5,7-difluoro-epicatechin-3-O-gallate demonstrated a dose-dependent inhibition of cell viability in the low micromolar range. These effects suggest that (-)-epicatechin-3-O-gallate and the more effective (-)-5,7-difluoro-epicatechin-3-O-gallate could be therapeutically used to inhibit tumorigenesis during initiation, promotion, and progression by diminishing the amount of inflammation due to a reduction of inflammatory lymphocytes. Further studies are needed to prove this in in vivo experiments.

Adjuvant intravesical treatment with a standardized mistletoe extract to prevent recurrence of superficial urinary bladder cancer.

BACKGROUND: Adjuvant intravesical Bacillus Calmette-Guerin (BCG) treatment after resection of non invasive superficial bladder cancer has been shown to significantly decrease tumor recurrence. However, the serious local and systemic side-effects of this treatment have promoted the use of other immunoactive substances, which, to date, have all failed to show efficacy equal to BCG therapy. PATIENTS AND METHODS: In the present phase I/II clinical trial, an aqueous mistletoe extract, standardized to mistletoe lectin, was applied intravesically to 30 patients with superficial urothelial bladder carcinomas of stages pTa and pT1, grades 1 to 2. After transurethral resection, each patient received 6 instillations at weekly intervals of 50 ml of the extract with mistletoe lectin concentrations between 10 ng/ml and 5000 ng/ml. This was retained in the bladder for 2 hours. Three patients per group received a dose, which was then doubled in the next group. The clinical follow-up consisted of examinations by cystoscopy, cytology and random biopsies. RESULTS: Within the observation time of 12 months, 9 patients had tumor recurrence, while 21 patients remained tumor-free. This recurrence rate was comparable to that of local historical controls with superficial bladder cancer of the same stages and grades that had been treated with adjuvant BCG. The tolerability of the intravesically-administered mistletoe extract was very good. None of the study patients had local or systemic side-effects according to the WHO classification 1-4. CONCLUSION: From these results, it is concluded that the standardized mistletoe extract could be a potential adjuvant therapy for superficial bladder cancer. Further studies may show the optimal intravesical treatment regimen.

Adjuvant intravesical treatment of superficial bladder cancer with a standardized mistletoe extract.

PURPOSE: Adjuvant intravesical immunotherapy with bacillus Calmette-Guerin (BCG) for noninvasive superficial bladder cancer has been shown to decrease tumor recurrence significantly. However, serious local and systemic side effects of this treatment have promoted the use of other immunoactive substances, which to date have failed to show efficacy equal to that of BCG immunotherapy. MATERIALS AND METHODS: In the current phase I/II clinical trial an aqueous mistletoe extract standardized to mistletoe lectin was administered intravesically to 30 patients with superficial urothelial bladder carcinoma. About 4 weeks after transurethral resection each patient received 6 instillations at weekly intervals of 50 ml extract with mistletoe lectin concentrations between 10 and 5,000 ng/ml, which was retained in the bladder for 2 hours. Three patients per group received a dose, which was then doubled in the next group. Clinical followup consisted of examinations with cystoscopy, cytology and random biopsies. To detect cytokines and tumor necrosis factor-p75 receptor venous blood and urine samples were taken before instillation, and 2, 6 and 24 hours thereafter. RESULTS: The tolerability of intravesically administered mistletoe extract was good at all applied concentrations. None of the patients had local or systemic side effects according to WHO classification 1-4. Within the 12-month observation time study patients with pTa G2 and pT1 G2 tumors showed a recurrence rate of 33%, comparable to that in a local historical control group of patients with equal stage and grade who were treated with adjuvant BCG. Comparison of urine cytokine levels before instillation, and 2, 6 and 24 hours thereafter brought about no significant alterations in all measured cytokines. CONCLUSIONS: From these results it is concluded that standardized mistletoe extract could be a potential alternative adjuvant therapy for superficial bladder cancer. Nevertheless, the optimal intravesical treatment regimen has yet to be defined.