Multifunctional Cyanine-Based Theranostic Probe for Cancer Imaging and Therapy

Cancer is one of the leading causes of death in the world. A cancer-targeted multifunctional probe labeled with the radionuclide has been developed to provide multi-modalities for NIR fluorescence and nuclear imaging (PET, SPECT), for photothermal therapy (PTT), and targeted radionuclide therapy of cancer. In this study, synthesis, characterization, in vitro, and in vivo biological evaluation of the cyanine-based probe (DOTA-NIR790) were demonstrated. The use of cyanine dyes for the selective accumulation of cancer cells were used to achieve the characteristics of tumor markers. Therefore, all kinds of organ tumors can be targeted for diagnosis and treatment. The DOTA-NIR790 labeled with lutetium-111 could detect original or metastatic tumors by using SPECT imaging and quantify tumor accumulation. The β-emission of 177Lu-DOTA-NIR790 can be used for targeted radionuclide therapy of tumors. The DOTA-NIR790 enabled imaging by NIR fluorescence and by nuclear imaging (SPECT) to monitor in real-time the tumor accumulation and the situation of cancer therapy, and to guide the surgery or the photothermal therapy of the tumor. The radionuclide-labeled heptamethine cyanine based probe (DOTA-NIR790) offers multifunctional modalities for imaging and therapies of cancer.

Poly(methacrylic Acid)-Cellulose Brushes as Anticancer Porphyrazine Carrier

The prospective strategy for treatment of cancer is based on the application of nano-sized macromolecular carriers, which are able penetrate inside and can be accumulated within tumor tissue. In this work graft copolymers of cellulose and poly(methacrylic acid) has been prepared and tested as a nanocontainers for the delivery of drug to tumor. For this purpose, two derivatives of porphyrazine suitable for photodynamic cancer therapy were loaded into prepared polymer brush. Fluorescence imaging was applied for monitoring of accumulation of porphyrazine in the CT26 murine colon carcinoma. The selective accumulation of cellulose brush loaded with porphyrazine in tumor was demonstrated by fluorescence intensity contrast between the tumor area and normal tissues. The tumor growth rate after photodynamic therapy were assessed and inhibition of its growth was revealed.

Targeting activated macrophages intracellular milieu to augment anti-inflammatory drug potency

We present pH-responsive phosphorylcholine polymersomes ability to target activated macrophages via scavenger receptors, enter them via endocytosis, and escape from early endosomes enabling the intracellular drug delivery. Using an arthritis experimental model and the gold standard disease-modifying anti-rheumatic drug, methotrexate, we prove that polymersomes augment therapeutic efficacy while minimizing the off-target effect. First, we demonstrate the selective accumulation of polymersomes within the inflamed synovial tissues and cells, including macrophages. Second, we show the beneficial therapeutic effect of methotrexate loaded polymersomes in preventing both joint inflammation and further damage. Hence, we prove the therapeutic potential of polymersomes in enhancing the complete prevention of arthritis progression, which makes it a promising nano therapy for arthritis treatment as well as other inflammatory disorders.

The Entangled Conductive Structure of CB/PA6/PP MFCs and Their Electromechanical Properties

In this work, carbon black (CB)/polyamide 6 (PA6)/polypropylene (PP) microfibrillar composites (MFCs) were fabricated through an extrusion (hot stretching) heat treatment process. The CB-coated conductive PA6 microfibrils with high aspect ratio were in situ generated as a result of the selective accumulation of CB at the interface. At the proper temperature, a 3D entangled conductive structure was constructed in the PP matrix, due to topological entanglement between these conductive microfibrils. This unique conductive structure provided the PP composites with a low electrical conductivity percolation threshold. Moreover, the electromechanical properties of conductive MFCs were investigated for the first time. A great stability, a high sensitivity and a nice reproducibility were achieved simultaneously for CB/PA6/PP MFCs. This work provides a universal and low-cost method for the conductive polymer composites’ (CPCs) fabrication as sensing materials.

Cancer Treatment Based on the Selective Accumulation of a Photosensitiser and Laser Light Irradiation: A Review

Background: Cancer Photodynamic Therapy (CPDT) is a promising future treatment quality based on the selective accumulation of a photosensitiser in the malignant tissues and the dependent irradiation with laser light. Objective: The aim of this work was to estimate an optimum effect involves the performance of a photosensitizing agent served by irradiation at a wavelength corresponding to an absorbance band of the sensitizer. In the appearance of oxygen, a series of effects lead to direct tumour cell death and damage to the microvasculature and initiation of a local inflammatory reaction. Methods: Photosensitiser is a material that sensitizes an organism, cell, or tissue to the light. It is a deeprooted part of CPDT, which absorbed by cancerous cells and exposed to laser light, gets activated, damaging and killing cancer cells. The direct targeting of laser source on hyper proliferative tissue and its preferential origin absorption at the targeted site gives rise CPDT double selectivity with least damage to adjacent normal tissues. Results: Photosensitiser absorbs the light and then produces an active form of oxygen, which destroys nearby cancer cells. The photosensitiser is able to spoil the blood vessels in the tumour, that way preventing cancer from receiving any necessary nutrients. The light which needed to activate most of the photosensitisers cannot pass through more than about one-third of an inch of tissue, because of that reason, the CPDT is usually used to treat cancer on or just under the skin or on the lining of internal organs. In addition, CPDT may activate the immune system to attack the tumour cells, directly killing cancer cells. Conclusion: This review focuses on the aspects of CPDT as an advanced and original site directed therapy for cancer treatment and the other non-oncogenic diseases. Minimal average of tissue toxicity controlled a long-term morbidity, deficiency of intrinsic or acquired resistance mechanisms. Bangladesh Med Res Counc Bull 2020; 46(3): 150-153

Self-assembly of peptide nanofibers for imaging applications

Pathological stimuli-responsive self-assembly of peptide nanofibers enables selective accumulation of imaging agent cargos in the stimuli-rich regions of interest. It provides enhanced imaging signals, biocompatibility, and tumor/disease accessibility and retention,...

Accumulation of Elements in Biodeposits on the Stone Surface in Urban Environment. Case Studies from Saint Petersburg, Russia

The pattern of elements accumulation in biodeposits formed by living organisms and extracellular products of their metabolism (biofouling, primary soils) on different bedrocks (of the monuments of Historical necropoleis in Saint Petersburg) were studied by a complex of biological and mineralogical methods (optical microscopy, SEM, EDX, XRD, ICP MS, XRFS). The content of 46 elements in biodeposits with various communities of microorganisms is determined. The model recreating the picture of the input and selective accumulation of elements in biodeposits on the stone surface in outdoor conditions is assumed. It is shown that the main contribution to the elemental composition of biodeposits is made by the environment and the composition of the microbial community. The contribution of leaching under the action of microbial metabolites of mineral grains, entering biodeposits from the environment, is significantly greater than that of the underlying rock.