Marcin Binkowski

A multi-target approach for pain treatment: dual inhibition of fatty acid amide hydrolase and TRPV1 in a rat model of osteoarthritis.

Abstract The pharmacological inhibition of anandamide (AEA) hydrolysis by fatty acid amide hydrolase (FAAH) attenuates pain in animal models of osteoarthritis (OA) but has failed in clinical trials. This may have occurred because AEA also activates transient receptor potential vanilloid type 1 (TRPV1), which contributes to pain development. Therefore, we investigated the effectiveness of the dual FAAH–TRPV1 blocker OMDM-198 in an MIA-model of osteoarthritic pain. We first investigated the MIA-induced model of OA by (1) characterizing the pain phenotype and degenerative changes within the joint using X-ray microtomography and (2) evaluating nerve injury and inflammation marker (ATF-3 and IL-6) expression in the lumbar dorsal root ganglia of osteoarthritic rats and differences in gene and protein expression of the cannabinoid CB1 receptors FAAH and TRPV1. Furthermore, we compared OMDM-198 with compounds acting exclusively on FAAH or TRPV1. Osteoarthritis was accompanied by the fragmentation of bone microstructure and destroyed cartilage. An increase of the mRNA levels of ATF3 and IL-6 and an upregulation of AEA receptors and FAAH in the dorsal root ganglia were observed. OMDM-198 showed antihyperalgesic effects in the OA model, which were comparable with those of a selective TRPV1 antagonist, SB-366,791, and a selective FAAH inhibitor, URB-597. The effect of OMDM-198 was attenuated by the CB1 receptor antagonist, AM-251, and by the nonpungent TRPV1 agonist, olvanil, suggesting its action as an “indirect” CB1 agonist and TRPV1 antagonist. These results suggest an innovative strategy for the treatment of OA, which may yield more satisfactory results than those obtained so far with selective FAAH inhibitors in human OA.

X-ray Microtomography (XMT) of Fossil Brachiopod Shell Interiors for Taxonomy

The ability to see and understand the three-dimensional structure of an investigated object plays a key role in studying fossil remains. All living organisms are formed in three-dimensions, but unfortunately fossilization processes often reduce overall shape, making it difficult to gather information about real overall appearance, functionality, and inner structure. Here, using a specimen of the brachiopod Tere bratula terebratula we demonstrate a non-destructive technique for exploring the 3-D internal structure of fossil remains. The use of tomography allows the construction of a set of transverse serial sections in the manner used by brachiopod researchers for decades.

Preservation and sterilization methods of the meniscal allografts: literature review

Abstract Nowadays, there are four types of meniscal allografts known: fresh, cryopreserved, deep-frozen and lyophilized ones but only two of them are widely used in clinical practice. Use of different types of meniscal allografts still remains controversial due to preparation method, their biomechanical properties as well as cost which is connected with processing and storage. The main aim of this review is to present the current status of knowledge concerning meniscal allograft preservation and sterilization, especially the advantages and disadvantages of each method. Authors wanted to show a broad spectrum of methods used and conceptions presented by other authors. The second aim is to gather available information about meniscal preservation and sterilization methods in one paper. Deep-frozen and cryopreserved meniscal allografts are the most frequently used ones in the clinical practice. The use of fresh grafts stays controversial but also has many followers. Lyophilized grafts in turn are not applied at present due to some serious drawbacks including reduction of tensile strength, poor rehydration, graft shrinkage and post-transplantation joint effusion as well as increased risk of meniscal size reduction. An application of sterilizing agents make the meniscal allograft free from the bacteria and viruses, but also it may cause serious structure changes. Therefore, choosing just one ideal method of meniscal allograft preservation and sterilization is complicated and should be based on broad knowledge and experience of surgeon performing the transplantation.

A moment from before 365 Ma frozen in time and space

This study presents a detailed analysis of an exceptionally well-preserved articulated specimen of the trilobite Trimerocephalus from the Late Devonian of the Holy Cross Mountains in Poland. X-ray microtomography reveals the oldest direct evidence for a moulting episode known from the fossil record. The process of moulting as well as associated features observed in the investigated specimen are interpreted by comparison with extinct and extant Xiphosurida arthropods, which survived global P/T extinction and are among the closest extant relatives of trilobites. A very special moment frozen in time and space millions years ago provides rare insights into the behavior and physiology of these long-extinct arthropods.

Structure and Ultrastructure of the Endodermal Region of the Alimentary Tract in the Freshwater Shrimp Neocaridina heteropoda (Crustacea, Malacostraca)

The freshwater shrimp Neocaridina heteropoda (Crustacea, Malacostraca, Decapoda) originates from Asia and is one of the species that is widely available all over the world because it is the most popular shrimp that is bred in aquaria. The structure and the ultrastructure of the midgut have been described using X-ray microtomography, transmission electron microscopy, light and fluorescence microscopes. The endodermal region of the alimentary system in N. heteropoda consists of an intestine and a hepatopancreas. No differences were observed in the structure and ultrastructure of males and females of the shrimp that were examined. The intestine is a tube-shaped organ and the hepatopancreas is composed of two large diverticles that are divided into the blind-end tubules. Hepatopancreatic tubules have three distinct zones – proximal, medial and distal. Among the epithelial cells of the intestine, two types of cells were distinguished – D and E-cells, while three types of cells were observed in the epithelium of the hepatopancreas – F, B and E-cells. Our studies showed that the regionalization in the activity of cells occurs along the length of the hepatopancreatic tubules. The role and ultrastructure of all types of epithelial cells are discussed, with the special emphasis on the function of the E-cells, which are the midgut regenerative cells. Additionally, we present the first report on the existence of an intercellular junction that is connected with the E-cells of Crustacea.

X-ray Microtomography Analysis of the Aluminum Alloy Composite Reinforced by SiC After Friction Stir Processing

Despite many years of using friction stir processing (FSP), there are many unexplained aspects concerning the processes which appear during FSP: determining the direction of flow and mixing of the materials and the degree of mixing and microstructure fragmentation in specific areas. This paper presents the impact of FSP on the micro- and macrostructure of the composite with hypo-eutectic Si matrix reinforced by SiC particles. The analysis of the structure of the processed area in FSP in the relation to the microstructure of the base material has been made using x-ray microtomography. The results of these studies have been juxtaposed with studies using microscopic methods (light microscopy and SEM). The microtomography images revealed an additional separation on the advancing side and the weld nugget, where on the basis of a 3D reconstruction a layer microstructure on the direction of linear movement of the tool has been demonstrated. The analyses have revealed a limited flow of the material above the weld nugget. The main advantages of the research method applied were the possibility to show the invisible or barely visible elements of the microstructure using standard test methods and the ability to analyze the microstructure changes uninterruptedly in different directions in the volume of the material.

Bone tunnel enlargement following hamstring anterior cruciate ligament reconstruction: a comprehensive review

ABSTRACT Nowadays, bone tunnel enlargement (BTE) after anterior cruciate ligament reconstruction is a well-known phenomenon. It has been identified, investigated and described by many authors during the last thirty years. Nevertheless, the etiology of bone tunnel enlargement still remains unclear. It is known that the causes are multifactorial and may include the surgical technique, the method of fixation, materials used, type of graft as well as biological factors. Due to the recent popularization of the use of hamstring grafts in anterior cruciate ligament reconstruction, the bone tunnel enlargement phenomenon is becoming increasingly common. In this review article, the authors focus on compiling current knowledge about the etiology, diagnosis, and the possibility of reducing the occurrence of this phenomenon by using the latest methods of supporting reconstruction surgery.

Image-based finite element modeling of the three-point bending test of cortical bone

The numerical simulation of the response of bone tissue to loading is a very common method in the biomedical engineering. The high diversity of bone quality, fractures and metabolic diseases, requires different approaches to numerical simulation. The main aim of this study was image-based finite element modeling (FEM) of the three-point bending tests of cortical bone. The results from the simulation performed based on own materials can be then used to non-destructive prediction of the bone mechanical strength. The samples were scanned by X-ray microcomputed tomography (XMT). Grey values of the imaged phantom were calibrated to known values of the phantom densities. It enabled estimation of the calibration curve for mineral level in bone, that was further applied to the calculation of bone density and the estimation of the material parameters in the FE model. In one example, the finite element analysis gives the deflection y=0.7 mm that match results from experiments where deflection was equal to y =0,69mm. The reported studies delivered useful data for future prediction of the mechanical parameters based on only imaging data.

Effects of Polylactide Copolymer Implants and Platelet-Rich Plasma on Bone Regeneration within a Large Calvarial Defect in Sheep

The aim of this study was to verify whether L-lactide/DL-lactide copolymer 80/20 (PLDLLA) and platelet-rich plasma (PRP) trigger bone formation within critical-sized calvarial defects in adult sheep (n = 6). Two craniectomies, each ca. 3 cm in diameter, were created in each animal. The first craniectomy was protected with an inner polylactide membrane, filled with PRP-polylactide granules, and covered with outer polylactide membrane. The second control craniectomy was left untreated. The animals were euthanized at 6, 7, 17, 19, 33, and 34 weeks after surgery, and the quality and the rate of reossification were assessed histomorphometrically and microtomographically. The study demonstrated that application of implants made of PLDLLA 80/20 combined with an osteopromotive substance (e.g., PRP) may promote bone healing in large calvarial defect in sheep. These promising proof-of-concept studies need to be verified in the future on a larger cohort of animals and over a longer period of time in order to draw definitive conclusions.

Late Jurassic jaw bones of Halecomorph fish (Actinopterygii: Halecomorphi) studied with X-ray microcomputed tomography

New finds of Halecomorphi fish remains from Late Jurassic limestones of Owadów-Brzezinki (Poland) are investigated using X-ray microcomputed tomography (XMT) revealing details of jaw bones for actinopterygian fish histology. Three-dimensional (3-D) reconstruction allows for correct taxonomical verification. The possibility of 3-D printing gives the opportunity for work with a model in any desired scale without risk of damaging the specimen. Błażej Błażejowski. Institute of Paleobiology, Polish Academy of Sciences, Twarda 51/55, 00-818 Warszawa, Poland. bblazej@twarda.pan.pl Paul Lambers. Universiteitsmuseum Utrecht, Lange Nieuwstraat 106, 3512 PN Utrecht, The Netherlands, p.h.lambers@uu.nl Piotr Gieszcz. Independent Center for Advanced Research machinic.it, Stawki 4c/10, 00-193 Warszawa, Poland, pjogi@interia.eu Daniel Tyborowski. Museum and Institute of Zoology, Polish Academy of Sciences, Wilcza 64, 00-679 Warszawa, Poland, d.tyborowski@student.uw.edu.pl Marcin Binkowski. Department of Computer Science and Materials Science, University of Silesia, Katowice, Poland, marcin.binkowski@us.edu.pl