다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

One of the most intriguing protein materials found in nature is bone, a material composed of assemblies of tropocollagen molecules and tiny hydroxyapatite mineral crystals that form an extremely tough, yet lightweight, adaptive and multifunctional material. Bone has evolved to provide structural support to organisms, and therefore its mechanical properties are of great physiological relevance. In this article, we review the structure and properties of bone, focusing on mechanical deformation and fracture behavior from the perspective of the multidimensional hierarchical nature of its structure. In fact, bone derives its resistance to fracture with a multitude of deformation and toughening mechanisms at many size scales ranging from the nanoscale structure of its protein molecules to the macroscopic physiological scale.

On the Mechanistic Origins of Toughness in Bone

Electrospinning for Tissue Engineering Applications

The development of immune-checkpoint inhibitors (ICIs) has heralded a new era in cancer treatment, enabling the possibility of long-term survival in patients with metastatic disease, and providing new therapeutic indications in earlier-stage settings. As such, characterizing the long-term implications of receiving ICIs has grown in importance. An abundance of evidence exists describing the acute clinical toxicities of these agents, although chronic effects have not been as well catalogued. Nonetheless, emerging evidence indicates that persistent toxicities might be more common than initially suggested. While generally low-grade, these chronic sequelae can affect the endocrine, rheumatological, pulmonary, neurological and other organ systems. Fatal toxicities also comprise a diverse set of clinical manifestations and can occur in 0.4–1.2% of patients. This risk is a particularly relevant consideration in light of the possibility of long-term survival. Finally, the effects of immune-checkpoint blockade on a diverse range of immune processes, including atherosclerosis, heart failure, neuroinflammation, obesity and hypertension, have not been characterized but remain an important area of research with potential relevance to cancer survivors. In this Review, we describe the current evidence for chronic immune toxicities and the long-term implications of these effects for patients receiving ICIs. Immune-checkpoint inhibitors (ICIs) have dramatically improved the outcomes of patients with advanced-stage solid tumours, including the potential for long-term remission in a subset. However, long-term follow-up data reveal a risk of chronic toxicities from these agents, which can have important quality-of-life implications. In this Review, the authors describe the current level of evidence of chronic toxicities of ICIs and their implications for patients 

/pdf/immune-checkpoint-inhibitors-long-term-implications-of-11f71ovn.pdf

Immune-checkpoint inhibitors: long-term implications of toxicity

Recent developments in physical, biological, chemical, and hybrid treatment techniques for removing emerging contaminants from wastewater.

Zirconia doped Hydroxyapatite (HAP) nanocrystals [Ca10(PO4)6−x(ZrO2)x(OH)2]; (0 ≤ x ≤ 1 step 0.2) were synthesized using simple low cost facile method. The crystalline phases were examined by X-ray diffraction (XRD). The crystallinity percentage decreased with increasing zirconia content for the as-synthesized samples. The existence of zirconia as secondary phase on the grain boundaries; as observed from scanning electron micrographs (FESEM); resulted in negative values of microstrain. The crystallite size was computed and the results showed that it increased with increasing annealing temperature. Thermo-gravimetric analysis (TGA) assured the thermal stability of the nano crystals over the temperature from room up to 1200 °C depending on the zirconia content. The corrosion rate was found to decrease around 25 times with increasing zirconia content from x = 0.0 to 1.0. Microhardness displayed both compositional and temperature dependence. For the sample (x = 0.6), annealed at 1200 °C, the former increased up to 1.2 times its original value (x = 0.0).

/pdf/physico-mechanical-and-morphological-features-of-zirconia-zt45fk5ym5.pdf

Physico-mechanical and morphological features of zirconia substituted hydroxyapatite nano crystals.

Manipulation of AgNPs coated on selenium/carbonated hydroxyapatite/ε-polycaprolactone nano-fibrous via pulsed laser deposition for wound healing applications

Graphene oxide, silver and copper oxide nanoparticles display photoactivated antibacterial behavior owing to their ability to generate charge carriers via light exposure. In this work, silver nanoparticles (AgNPs) and copper oxide nanoparticles (CuONPs) were embedded through graphene oxide (GO) using laser ablation technique. The microstructural behavior of the synthesized compositions has been investigated via XRD and TEM. The optical properties were studied by (UV–Vis), while the antibacterial properties were investigated in addition to the cell viability towards normal cell line (HFB4) in vitro. The antibacterial activity of GO was enhanced significantly with addition nanoparticles; by meaning, the inhibition zone enlarged from 5.4 mm with pure GO to be around 11.2 mm against E. coli with contribution of CuONPs. This trend of enhancement suggests that GO could be a great platform for different kinds of photo-activated antibacterial to be recommended for versatile biomedical applications.

Silver and copper oxide nanoparticles-decorated graphene oxide via pulsed laser ablation technique: Preparation, characterization, and photoactivated antibacterial activity

Nano-hydroxyapatite/chitosan (nano-HAP/CS) composites with high compressive strength were synthesized using microwave assisted co-precipitation. Co-Doping using Mg2+ and Ag+ was carried out simultaneously in HAP resulting in the formula: [MgxAgyCa(10−x−y)(PO4)6(OH2); 0 ≤ (x + y) ≤ 1]. The samples were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM). The results illustrated that the shape, size and crystallinity index of the prepared nano-HAP crystals were similar to those of natural bone. Doping by Ag+ was performed to produce an anti-bacterial effect, while Mg2+ dopant appeared to be a crucial factor in improving the mechanical properties. Furthermore, mechanical testing exhibited that the maximum compressive strength of the new composite was 15 MPa. The multifunctional non-sintered materials showed promising results in drug loaded bioceramics with improved mechanical features in bone tissue engineering.

M.K. Ahmed

Papers

Physico-mechanical and morphological features of zirconia substituted hydroxyapatite nano crystals.

Manipulation of AgNPs coated on selenium/carbonated hydroxyapatite/ε-polycaprolactone nano-fibrous via pulsed laser deposition for wound healing applications

Silver and copper oxide nanoparticles-decorated graphene oxide via pulsed laser ablation technique: Preparation, characterization, and photoactivated antibacterial activity

Physico-mechanical properties of Mg and Ag doped hydroxyapatite/chitosan biocomposites

Synthesis and antibacterial activity of graphene oxide decorated by silver and copper oxide nanoparticles