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

Most cancer drugs are designed to interfere with one or more events in cell proliferation or survival. As healthy cells may also need to proliferate and avoid apoptosis, anticancer agents can be toxic to such cells. To minimize these toxicities, strategies have been developed wherein the therapeutic agent is targeted to tumour cells through conjugation to a tumour-cell-specific small-molecule ligand, thereby reducing delivery to normal cells and the associated collateral toxicity. This Review describes the major principles in the design of ligand-targeted drugs and provides an overview of ligand-drug conjugates and ligand-imaging-agent conjugates that are currently in development.

Principles in the design of ligand-targeted cancer therapeutics and imaging agents

Radiometals possess an exceptional breadth of decay properties and have been applied to medicine with great success for several decades. The majority of current clinical use involves diagnostic procedures, which use either positron-emission tomography (PET) or single-photon imaging to detect anatomic abnormalities that are difficult to visualize using conventional imaging techniques (e.g., MRI and X-ray). The potential of therapeutic radiometals has more recently been realized and relies on ionizing radiation to induce irreversible DNA damage, resulting in cell death. In both cases, radiopharmaceutical development has been largely geared toward the field of oncology; thus, selective tumor targeting is often essential for efficacious drug use. To this end, the rational design of four-component radiopharmaceuticals has become popularized. This Review introduces fundamental concepts of drug design and applications, with particular emphasis on bifunctional chelators (BFCs), which ensure secure consolidation of the radiometal and targeting vector and are integral for optimal drug performance. Also presented are detailed accounts of production, chelation chemistry, and biological use of selected main group and rare earth radiometals.

Radioactive Main Group and Rare Earth Metals for Imaging and Therapy

In view of the lack of a specific drug-sustained release system that is responsive to chronic wounds of the type II diabetic foot, and the demands for frequent movement at the foot wound, pH/glucose dual-responsive metformin-released adhesion-enhanced self-healing easy-removable antibacterial antioxidant conductive hemostasis multifunctional phenylboronic acid and benzaldehyde bifunctional polyethylene glycol-co-poly(glycerol sebacic acid)/dihydrocaffeic acid and l-arginine cografted chitosan (PEGS-PBA-BA/CS-DA-LAG, denoted as PC) hydrogel dressings were constructed based on the double dynamic bond of the Schiff-base and phenylboronate ester. It was further demonstrated that the PC hydrogel promotes wound healing by reducing inflammation and enhancing angiogenesis in a rat type II diabetic foot model. In addition, the addition of metformin (Met) and graphene oxide (GO), as well as their synergy, were confirmed to better promote wound repair in vivo. In summary, adhesion-enhanced self-healing multifunctional PC/GO/Met hydrogels with stimuli-responsive metformin release ability and easy removability have shown a promoting effect on the healing of chronic athletic diabetic wounds and provide a local-specific drug dual-response release strategy for the treatment of type II diabetic feet.

pH/Glucose Dual Responsive Metformin Release Hydrogel Dressings with Adhesion and Self-Healing via Dual-Dynamic Bonding for Athletic Diabetic Foot Wound Healing.

Which elements are essential for human life? Here we make an element-by-element journey through the periodic table and attempt to assess whether elements are essential or not, and if they are, whether there is a relevant code for them in the human genome. There are many difficulties such as the human biochemistry of several so-called essential elements is not well understood, and it is not clear how we should classify elements that are involved in the destruction of invading microorganisms, or elements which are essential for microorganisms with which we live in symbiosis. In general, genes do not code for the elements themselves, but for specific chemical species, i.e. for the element, its oxidation state, type and number of coordinated ligands, and the coordination geometry. Today, the biological periodic table is in a position somewhat similar to Mendeleev's chemical periodic table of 1869: there are gaps and we need to do more research to fill them. The periodic table also offers potential for novel therapeutic and diagnostic agents, based on not only essential elements, but also non-essential elements, and on radionuclides. Although the potential for inorganic chemistry in medicine was realized more than 2000 years ago, this area of research is still in its infancy. Future advances in the design of inorganic drugs require more knowledge of their mechanism of action, including target sites and metabolism. Temporal speciation of elements in their biological environments at the atomic level is a major challenge, for which new methods are urgently needed.

https://royalsocietypublishing.org/doi/pdf/10.1098/rsta.2014.0182

The elements of life and medicines.

Adipose-derived mesenchymal stem/stromal cells (ADMSC) are one of the major stromal cells in the breast cancer microenvironment that promote cancer progression. Previous studies on the effects of ADMSC on breast cancer metastasis and drug resistance, using two-dimensional (2D) cultures, remained inconclusive. In the present study, we compared cocultured ADMSC and human epidermal receptor 2 positive breast primary breast cancer cells (21PT) in 2D and three-dimensional (3D) cultures and then examined their response to doxorubicin (DOX). We examined 3D bioprinted constructs with breast cancer cells in the middle and ADMSC in the edge region, which were made by using dual hydrogel-based bioinks. We found that the percentage of cleaved Caspase-3 positive cells was significantly lower in the bioprinted constructs with ADMSC and 21PT than that in the cancer cell alone constructs, in response to low DOX dose. We further increased the thickness of the ADMSC layers to mimic the status of obesity and then examined the effect of ADMSC thickness on DOX resistance and lysyl oxidase (LOX) secretion. In the moderate and thick-layered ADMSC constructs, significantly more cells were stained negative for cleaved Caspase-3, indicating less apoptosis. Both ADMSC and 21PT intrinsically expressed LOX, regardless of changes in thickness or DOX administration. Notably, treatment with a LOX inhibitor significantly decreased the stiffness in the ADMSC region but did not affect the stiffness in the 21PT region. In addition, LOX inhibitor treatment enhanced DOX sensitivity of 21PT in the bioprinted constructs, as seen by a decrease in LOX secretion and downregulation of adenosine triphosphate-binding cassette transporter gene expression. Taken together, we demonstrate that 3D bioprinted these breast cancer models faithfully reproduce in vivo conditions and should provide better models for examining breast cancer biology and for screening for drug discoveries.

3D Bioprinting of Breast Cancer Models for Drug Resistance Study

Functional reconstruction of craniomaxillofacial defects is challenging, especially for the patients who suffer from traumatic injury, cranioplasty, and oncologic surgery. Three-dimensional (3D) printing/bioprinting technologies provide a promising tool to fabricate bone tissue engineering constructs with complex architectures and bioactive components. In this study, we implemented multi-material 3D printing to fabricate 3D printed PCL/hydrogel composite scaffolds loaded with dual bioactive small molecules (i.e. resveratrol and strontium ranelate). The incorporated small molecules are expected to target several types of bone cells. We systematically studied the scaffold morphologies and small molecule release profiles. We then investigated the effects of the released small molecules from the drug loaded scaffolds on the behavior and differentiation of mesenchymal stem cells (MSCs), monocyte-derived osteoclasts, and endothelial cells. The 3D printed scaffolds, with and without small molecules, were further implanted into a rat model with a critical-sized mandibular bone defect. We found that the bone scaffolds containing the dual small molecules had combinational advantages in enhancing angiogenesis and inhibiting osteoclast activities, and they synergistically promoted MSC osteogenic differentiation. The dual drug loaded scaffolds also significantly promoted in vivo mandibular bone formation after 8 week implantation. This work presents a 3D printing strategy to fabricate engineered bone constructs, which can likely be used as off-the-shelf products to promote craniomaxillofacial regeneration.

https://iopscience.iop.org/article/10.1088/1758-5090/ab906e/pdf

Wen Shi

Papers

3D Bioprinting of Breast Cancer Models for Drug Resistance Study

3D printed composite scaffolds with dual small molecule delivery for mandibular bone regeneration

Fabrication of versatile dynamic hyaluronic acid-based hydrogels.

Anisotropic scaffolds for peripheral nerve and spinal cord regeneration.

3D printing of multilayered scaffolds for rotator cuff tendon regeneration