A case with CMTX1 disease showing transient ischemic-attack-like episodes

Charcot-Marie-Tooth (CMT) disease is a hereditary neurologic disease which affects the sensorial and motor fibers of the peripheral nerves. CMTX1 is an X-linked dominantly inherited subtype of CMT and is caused by mutations in gap junction beta 1 gene (GJB1). A small proportion of GJB1 mutations are associated with recurrent central nervous system findings. We describe a 15-year-old male patient with CMTX1 who had stroke-like findings along with foot deformities and peripheral neuropathy. Strokes and stroke-like attacks are rarely seen in children and adolescents. Herein, neurological signs, MRI findings and genetic results of a CMTX1 case are presented and discussed

Time-Gated Luminescence Detection for High-Throughput Screening of Protein Interaction and Inhibitions

High throughput screening (HTS) assays are a key component of the drug discovery processes. They are designed to identify biologically active molecules that can ultimately be used as therapeutic agents. Such assays use the power of automation to test thousands of molecules per day, and they require high reproducibility and robustness to be reliable. Current HTS technologies often employ fluorescence-based detection methods as a means of identifying potentially useful compounds. However, often high levels of non-specific fluorescence background emanating from biological assay components and, especially, library compounds can reduce sensitivity and lead to unacceptable rates of false positive results. The use of time-gated detection in combination with organic complexes of lanthanides, particularly Tb3+ and Eu3+, that have millisecond-scale excited-state lifetimes as luminescent reporters alleviates this problem. By implementing a delay of 10 microseconds or more between sample excitation and detection, nanosecond-scale fluorescence background is eliminated, resulting in HTS assays with very large signal-to-background ratios. Interactions between proteins are essential for cellular function. Many diseases are caused by mutations that disrupt or otherwise give rise to aberrant protein-protein interactions (PPIs). While enzyme active sites and cell surface receptors have been the most common drug discovery targets, there is increasing interest in developing small molecule therapeutics that can disrupt PPIs. One of the key challenges in targeting PPIs with small molecules is that the interface between two interacting proteins is a relatively large, flat surface, as opposed to a distinct binding pocket. Moreover, there is often no structural information available about PPI interfaces, and this makes rational design of potential inhibitors difficult or impossible. For this reason, HTS has proven to be an important tool in the discovery process for PPI inhibitors that have been developed thus far, and it will continue to be play an important role in future efforts. The main objective of the studies described in this dissertation was to design HTS assays for PPI inhibition that can be readily adapted to almost any protein and that can be applied in purified biochemical preparations, cell lysates, or in living mammalian cells. The assay platform is based on the time-gated detection of Förster Resonance Energy Transfer between two overexpressed fusion proteins, one labeled with a luminescent Tb3+ complex and the other attached to a green fluorescent protein

Successful treatment of fasciola hepatica with metronidazole in a child: A case report

Fasciola hepatica is a zoonotic liver trematode that usually causes infection in cattle and sheep, and is transmitted to humans by consuming water and aquatic plants contaminated with metacercaria. The detection of Fasciola eggs in stools, serological evaluation and radiological evaluation are essential for diagnosis. Triclabendazole is the first-line therapy for fascioliasis. However, as triclabendazole is not an easily accessible drug in countries such as Turkey, it reveals a quest for alternative therapies. In this report, we present a 10-year-old boy with fascioliasis successfully treated with a course of metronidazole 1.5 g/ day for 3 weeks in 2020. During the follow-up, eosinophilia and radiological findings completely recovered. Here we report a case of pediatric fascioliasis that was cured with metronidazole successfully

Evaluation and discrimination of simvastatin-induced structural alterations in proteins of different rat tissues by FTIR spectroscopy and neural network analysis

Statins are commonly used to control hypercholesterolemia and to prevent cardiovascular diseases. Among the statins, Simvastatin is one of the most frequently prescribed statins because of its efficacy in reducing LDL lipoprotein cholesterol levels, its tolerability, and its reduction of cardiovascular risk and mortality. Conflicting results have been reported with regard to benefits (pleiotropic effects) as well as risks (adverse effects) of simvastatin on different soft and hard tissues. In the current study, Attenuated Total Reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy was used to obtain detailed information about protein conformational changes due to simvastatin therapy of soft tissues namely liver, testis, sciatic nerve and hard tissues such as femur and tibia. Protein secondary structural changes were predicted by intensity calculations from second derivative spectra and neural network (NN) analysis, using the amide I band (1700-1600 cm(-1)) of FTIR spectra. Moreover, based on protein secondary structural differences, hierarchial cluster analysis was carried out in the 1700-1600 cm(-1) region. The results of our study in liver, testis and sciatic nerve tissues revealed that simvastatin treatment significantly decreased alpha helix structure and beta sheet structure at 1638 cm(-1), while increased the anti-parallel and aggregated beta sheet and random coil structures implying a simvastatin-induced protein denaturation in treated groups. Different to soft tissues, the results of hard tissue studies on femur and tibia bones revealed increased alpha helix structure and decreased anti-parallel beta sheet, aggregated beta sheet and random coil structures implying more strengthened bone tissues in simvastatin-treated groups. Finally, the simvastatin-treated and control groups for all soft and bone tissues were successfully differentiated using cluster analysis. According to the heterogeneity values in the cluster analysis of these tissues, the sciatic nerve tissue was found to be the most affected tissue from simvastatin treatment among the studied soft tissues. In addition, the high heterogeneity value implied high secondary structural difference between control and simvastatin-treated groups in tibia bone tissues. These findings reveal that FTIR spectroscopy with bioinformatic analyses such as neural network and hierarchical clustering, allowed us to determine the simvastatin-induced protein conformational changes as adverse and pleitropic effects of the drug on different soft and hard tissues

A case with CMTX1 disease showing transient ischemic-attack-like episodes

Charcot-Marie-Tooth (CMT) disease is a hereditary neurologic disease which affects the sensorial and motor fibers of the peripheral nerves. CMTX1 is an X-linked dominantly inherited subtype of CMT and is caused by mutations in gap junction beta 1 gene (GJB1). A small proportion of GJB1 mutations are associated with recurrent central nervous system findings. We describe a 15-year-old male patient with CMTX1 who had stroke-like findings along with foot deformities and peripheral neuropathy. Strokes and stroke-like attacks are rarely seen in children and adolescents. Herein, neurological signs, MRI findings and genetic results of a CMTX1 case are presented and discussed. (c) 2017 Polish Neurological Society. Published by Elsevier Sp. z o.o. All rights reserved

An In-Silico Corrosion Model for Biomedical Applications for Coupling With In-Vitro Biocompatibility Tests for Estimation of Long-Term Effects

The release of metal particles and ions due to wear and corrosion is one of the main underlying reasons for the long-term complications of implantable metallic implants. The rather short-term focus of the established in-vitro biocompatibility tests cannot take into account such effects. Corrosion behavior of metallic implants mostly investigated in in-vitro body-like environments for long time periods and their coupling with long-term in-vitro experiments are not practical. Mathematical modeling and modeling the corrosion mechanisms of metals and alloys is receiving a considerable attention to make predictions in particular for long term applications by decreasing the required experimental duration. By using such in-silico approaches, the corrosion conditions for later stages can be mimicked immediately in in-vitro experiments. For this end, we have developed a mathematical model for multi-pit corrosion based on Cellular Automata (CA). The model consists of two sub-models, corrosion initialization and corrosion progression, each driven by a set of rules. The model takes into account several environmental factors (pH, temperature, potential difference, etc.), as well as stochastic component, present in phenomena such as corrosion. The selection of NiTi was based on the risk of Ni release from the implant surface as it leads to immune reactions. We have also performed experiments with Nickel Titanium (NiTi) shape memory alloys. The images both from simulation and experiments can be analyzed using a set of statistical methods, also investigated in this paper (mean corrosion, standard deviation, entropy etc.). For more widespread implementation, both simulation model, as well as analysis of output images are implemented as a web tool. Described methodology could be applied to any metal provided that the parameters for the model are available. Such tool can help biomedical researchers to test their new metallic implant systems at different time points with respect to ion release and corrosion and couple the obtained information directly with in-vitro tests

Automated Design of Macrocycles for Therapeutic Applications: from Small Molecules to Peptides and Proteins

Macrocycles and cyclic peptides are increasingly attractive therapeutic modalities as they often have improved affinity, are able to bind to extended protein interfaces and otherwise have favorable properties. Macrocyclization of a known binder molecule has the potential to stabilize its bioactive conformation, improve its metabolic stability, cell permeability and in certain cases oral bioavailability. Herein, we present an in silico approach that automatically generates, evaluates and proposes cyclizations utilizing a library of well-established chemical reactions and reagents. Using the three-dimensional (3D) conformation of the linear molecule in complex with a target protein as starting point, this approach identifies attachment points, generates linkers, evaluates the conformational landscape of suitable linkers and their geometric compatibility and ranks the resulting molecules with respect to their predicted conformational stability and interactions with the target protein. As we show here with several prospective and retrospective case studies, this procedure can be applied for the macrocyclization of small molecules and peptides and even PROTACs and proteins.The presented approach is an important step towards the enhanced utilization of macrocycles andcyclic peptides as attractive therapeutic modalities.</div