There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

Many types of nanoparticles (NPs) are tested for use in medical products, particularly in imaging and gene and drug delivery. For these applications, cellular uptake is usually a prerequisite and is governed in addition to size by surface characteristics such as hydrophobicity and charge. Although positive charge appears to improve the efficacy of imaging, gene transfer, and drug delivery, a higher cytotoxicity of such constructs has been reported. This review summarizes findings on the role of surface charge on cytotoxicity in general, action on specific cellular targets, modes of toxic action, cellular uptake, and intracellular localization of NPs. Effects of serum and intercell type differences are addressed. Cationic NPs cause more pronounced disruption of plasma-membrane integrity, stronger mitochondrial and lysosomal damage, and a higher number of autophagosomes than anionic NPs. In general, nonphagocytic cells ingest cationic NPs to a higher extent, but charge density and hydrophobicity are equally important; phagocytic cells preferentially take up anionic NPs. Cells do not use different uptake routes for cationic and anionic NPs, but high uptake rates are usually linked to greater biological effects. The different uptake preferences of phagocytic and nonphagocytic cells for cationic and anionic NPs may influence the efficacy and selectivity of NPs for drug delivery and imaging.

/pdf/the-role-of-surface-charge-in-cellular-uptake-and-22qmbuegnh.pdf

The role of surface charge in cellular uptake and cytotoxicity of medical nanoparticles.

Interpretation of X-ray Powder Diffraction Patterns . By H. Lipson and H. Steeple. Pp. viii + 335 + 3 plates. (Mac-millan: London; St Martins Press: New York, May 1970.) £4.

X-Ray Diffraction

Author(s): Vogel, Alfred; Venugopalan, Vasan | Abstract: The mechanisms of pulsed laser ablation of biological tissues were studied. The transiently empty space created between the fiber tip and the tissue surface improved the optical transmission to the target and thus increased the ablation efficiency. It was found that the structure and morphology also affect the energy transport among tissue constituents.

/pdf/mechanisms-of-pulsed-laser-ablation-of-biological-tissues-58cltfa63z.pdf

Mechanisms of pulsed laser ablation of biological tissues.

Abstract Noble metal alloy nanoclusters (NCs) are interesting systems as the properties of two or more elements can be combined in one particle, leading to interesting fluorescence phenomena. However, previous studies have been exclusively performed on ligand‐capped NCs from wet chemical synthesis. This makes it difficult to differentiate to which extent the fluorescence is affected by ligand‐induced effects or the elemental composition of the metal core. In this work, we used laser fragmentation in liquids (LFL) to fabricate colloidal gold‐rich bi‐metallic AuPt NCs in the absence of organic ligands and demonstrate the suitability of this technique to produce molar fraction series of 1nm alloy NC. We found that photoluminescence of ligand‐free NCs is not a phenomenon limited to Au. However, even minute amounts of Pt atoms in the AuPt NCs lead to quenching and red‐shift of the fluorescence, which may be attributed to the altered surface charge density.

https://onlinelibrary.wiley.com/doi/pdfdirect/10.1002/cphc.202200033

Influence of Pt Alloying on the Fluorescence of Fully Inorganic, Colloidal Gold Nanoclusters

Die vorliegende Erfindung bezieht sich auf eine biologisch wirksame Vorrichtung (1) mit einem aus einem Polymer gebildeten Grundkorper (2), in den bioaktive Nanopartikel (3) eines oder mehrerer Stoffe eingebettet sind, wobei die Nanopartikel (3) mindestens eines Stoffes auf ein biologisches Material, mit dem die Vorrichtung (1) kontaktierbar ist, proliferativ wirksam sind, und Nanopartikel (3) eines anderen Stoffes auf biologisches Material in der Umgebung der Vorrichtung (1) anti-proliferativ wirksam sind. Die Erfindung bezeiht sich daruber hinaus auch auf ein Verfahren zum Herstellen einer biologisch wirksamen Vorrichtung (1 ) mit einem aus einem Polymer gebildeten Grundkorper (2), wobei Nanopartikel (3) mehrerer unterschiedlicher Stoffe in einer spritzgussfahigen Flussigkeit (15) dispergiert und die Flussigkeit durch Spritzgiesen und Ausharten zu dem Polymer-Grundkorper (2) geformt wird, so dass die Nanopartikel (3) im Volumen des Polymer-Grundkorpers (2) dispergiert sind. Dabei werden die Nanopartikel (3) erfindungsgemas erzeugt, indem mindestens zwei Substrate (10) unterschiedlichen Materials in einem mit flussigem Material (12) gefullten Probegefas (11) angeordnet sind und die Nanopartikel (3) durch Abtragen von der Oberflache der Substrate (10) in der Flussigkeit (12) mittels Laserstrahlung (13) erzeugt werden.

Biologisch wirksame vorrichtung und verfahren zu ihrer herstellung

It is thought that thoracoscopic closure of a bronchial stump fistula is beyond the capabilities of current thoracoscopic techniques. We describe the successful use of thoracoscopy in the therapy of a late right main bronchial stump dehiscence after pneumonectomy and chemotherapy of a stage IIIA adenocarcinoma. We clipped the fistula with a Multifire Endo Hernia Stapler (Auto Suture) and we obtained intraoperative airtight closure of the fistula.

Video-assisted thoracoscopy for closure of a bronchial stump fistula.

Due to the ubiquity of environmental micro- and nanoplastics (MNPs), inhalation and ingestion by humans is very likely, but human health effects remain largely unknown. The NLRP3 inflammasome is a key player of the innate immune system and is involved in responses towards foreign particulate matter and the development of chronic intestinal and respiratory inflammatory diseases. We established NLRP3-proficient and -deficient THP-1 cells as an alternative in vitro screening tool to assess the potential of MNPs to activate the NLRP3 inflammasome. By investigating cytokine release (IL-1β and IL-8) and cytotoxicity after treatment with engineered nanomaterials, this in vitro approach was compared to earlier published ex vivo murine bone marrow-derived macrophages and in vivo data. This approach showed a strong correlation with previously published data, verifying that THP-1 cells are a suitable model to investigate NLRP3 inflammasome activation. We then investigated the proinflammatory potential of eight MNPs of different size, shape, and chemical composition. Only amine-modified polystyrene (PS-NH2) acted as a direct NLRP3 activator. However, polyethylene terephthalate (PET), polyacrylonitrile (PAN), and nylon (PA6) induced a significant increase in IL-8 release in NLRP3−/− cells. Our results suggest that most MNPs are not direct activators of the NLRP3 inflammasome, but specific MNP types might still possess pro-inflammatory potential via other pathways.

/pdf/assessing-the-nlrp3-inflammasome-activating-potential-of-a-fbc2cp5y.pdf

Assessing the NLRP3 Inflammasome Activating Potential of a Large Panel of Micro- and Nanoplastics in THP-1 Cells

This study presents an approach to the in-situ functionalization of metal nanoparticles, established by laser ablation in solution. Additives as polyvinylpyrrolidone (PVP), thiols or alkoxysilanes, that undergo physisorption with the surface of the nanoparticles, can be added to the solution and used as functionalization agents. The concentration of the additive influences the particle size distribution, which leads to plasmon resonance shifts, measurable by UV/VIS spectroscopy. As an example, the size dispersion and stability of generated gold nanoparticles can be controlled by varying the concentration of dodecanthiol as an additive during laser ablation of gold in n-hexane. Moreover, silica shells can be generated to protect metal nanoparticles (gold and copper) against oxidation by in-situ coating and subsequent silica shell formation.In-situ functionalizations of nanoparticles during laser ablation in liquids present a promising approach to the development of nanomaterials for biomedical applications.This study presents an approach to the in-situ functionalization of metal nanoparticles, established by laser ablation in solution. Additives as polyvinylpyrrolidone (PVP), thiols or alkoxysilanes, that undergo physisorption with the surface of the nanoparticles, can be added to the solution and used as functionalization agents. The concentration of the additive influences the particle size distribution, which leads to plasmon resonance shifts, measurable by UV/VIS spectroscopy. As an example, the size dispersion and stability of generated gold nanoparticles can be controlled by varying the concentration of dodecanthiol as an additive during laser ablation of gold in n-hexane. Moreover, silica shells can be generated to protect metal nanoparticles (gold and copper) against oxidation by in-situ coating and subsequent silica shell formation.In-situ functionalizations of nanoparticles during laser ablation in liquids present a promising approach to the development of nanomaterials for biomedical applications.

Stephan Barcikowski

Papers

Influence of Pt Alloying on the Fluorescence of Fully Inorganic, Colloidal Gold Nanoclusters

Biologisch wirksame vorrichtung und verfahren zu ihrer herstellung

Video-assisted thoracoscopy for closure of a bronchial stump fistula.

Assessing the NLRP3 Inflammasome Activating Potential of a Large Panel of Micro- and Nanoplastics in THP-1 Cells

Adding functionality to metal nanoparticles during femtosecond laser ablation in liquids