Rab7a is an enhancer of TPC2 activity regulating melanoma progression through modulation of the GSK3β/β-Catenin/MITF-axis.

Melanoma arising from pigment-producing melanocytes is the deadliest form of skin cancer. Extensive ultraviolet light exposure is a major cause of melanoma and individuals with low levels of melanin are at particular risk. Humans carrying gain-of-function polymorphisms in the melanosomal/endolysosomal two-pore cation channel TPC2 present with hypopigmentation, blond hair, and albinism.

Effects of media composition and light exposure on the electrochemical current response during scanning electrochemical microscopy live cell imaging.

Scanning Electrochemical Microscopy (SECM) has been used as a non-invasive electrochemical technique for studying cellular processes. SECM enables the quantification of cellular metabolites in real-time providing a deeper understanding of cellular responses to external stimuli. SECM imaging of living cells requires maintaining an ideal physiological environment to ensure reliable data collection on cellular reactivity.

Electrifying Fruit Juice: Integrating Applied Electroanalytical Chemistry into the Undergraduate Curriculum.

Electroanalytical chemistry has been advanced through portable devices, providing methods and sensors for the detection of analytes with high sensitivity and accuracy. This subfield of electrochemistry has the potential to be utilized in industry and analytical quality control, in general. This results in an increasing demand for trained personnel, capable of operating benchtop and portable electroanalytical equipment.

Cutting-edge biorecognition strategies to boost the detection performance of COVID-19 electrochemical biosensors: A review.

Electrochemical biosensors are known for their high sensitivity, selectivity, and low cost. Recently, they have gained significant attention and became particularly important as promising tools for the detection of COVID-19 biomarkers, since they offer a rapid and accurate means of diagnosis. Biorecognition strategies are a crucial component of electrochemical biosensors and determine their specificity and sensitivity based on the interaction of biological molecules, such as antibodies, enzymes, and DNA, with target analytes (e.

Cytochrome oxidase deficiency detection in human fibroblasts using scanning electrochemical microscopy.

Cytochrome oxidase deficiency (COXD) is an inherited disorder characterized by the absence or mutation in the genes encoding for the cytochrome oxidase protein (COX). COX deficiency results in severe muscle weakness, heart, liver, and kidney disorders, as well as brain damage in infants and adolescents, leading to death in many cases. With no cure for this disorder, finding an efficient, inexpensive, and early means of diagnosis is essential to minimize symptoms and long-term disabilities.

Temperature Effect on the Electrochemical Current Response during Scanning Electrochemical Microscopy of Living Cells.

Scanning electrochemical microscopy (SECM) is being used increasingly to monitor electrochemical processes at the interface of living cells and electrodes. This allows the detection and quantification of biomarkers that further the understanding of various diseases. Rapid SECM experiments are often carried out without monitoring the analyte solution temperature or are performed at room temperature.

Rapid and inexpensive voltammetric detection of ochratoxin A in wheat matrices.

Produced as toxic metabolites by fungi, mycotoxins, such as ochratoxin A (OTA), contaminate grain and animal feed and cause great economic losses. Herein, we report the fabrication of an electrochemical sensor consisting of an inexpensive and label-free carbon black-graphite paste electrode (CB-G-CPE), which was fully optimized to detect OTA in durum wheat matrices using differential pulse voltammetry (DPV). The effect of carbon paste composition, electrolyte pH and DPV parameters were studied to determine the optimum conditions for the electroanalytical determination of OTA.

The development of lipoprotein apheresis in Saxony in the last years.

Methods: Three hundred thirty-nine patients (230 men, 109 women) treated with lipoprotein apheresis in Saxony, Germany, in 2018 are described in terms of age, lipid pattern, risk factors, cardiovascular events, medication, and number of new admissions since 2014, and the data are compared with figures from 2010 to 2013.

Results: Patients were treated by 45.5 physicians in 16 lipoprotein apheresis centers.

Single-cell scanning photoelectrochemical microscopy using micro-optical-ring electrodes.

Microelectrodes as analytical sensing tools have gained immense popularity in a wide range of applications, ranging from probe design advancement to single live cell imaging. Micro-optical-ring electrodes (MOREs) are micro-scale ring-electrodes with an optical fiber core, that enables the MORE to conduct an optical signal while performing electrochemistry. Herein, we present a user-friendly and cost-effective method to fabricate MOREs for scanning photoelectrochemical microscopy (SPECM) applications.

Electrochemical Quantification of Tobramycin Retention in as Antimicrobial Susceptibility Indicator.

The emergence and spread of bacterial resistance to antibiotics has developed into one of the most challenging threats to public health. Antibiotic susceptibility tests (ASTs) for bacterial infections are now essential, because they provide guidance for physicians in the selection of antibiotics, to which bacteria will respond. Most current AST methods require long periods of time, because of bacterial growth and incubation, leading to a prolonged and overuse of broad-spectrum antibiotics.

Pico-molar electrochemical detection of ciprofloxacin at composite electrodes.

Rapid determination of antibiotic residues is crucial for both environmental monitoring and the ecosystem. The presented study explores the development of a sensitive, selective, and highly reproducible chemical sensor to detect the antibiotic ciprofloxacin (Cip) in 0.1 M NaNO and in tap water.

Pharma-molecule Transport across Bacterial Membranes: Detection and Quantification Approaches by Electrochemistry and Bioanalytical Methods.

Antibiotic resistance is a significant challenge encountered by healthcare systems on a global scale. Knowledge about membrane transport of antibiotics and other pharmacologically relevant molecules in bacteria is crucial towards understanding and overcoming antibiotic resistance, as drug resistance often depends on drug transport. This comprehensive literature review discusses the detection and quantification of membrane transport of pharma-molecules in bacteria and highlights the importance of molecule transport to antibiotic resistance.

Why Some Patients Undergoing Lipoprotein Apheresis Therapy Develop New Cardiovascular Events?

Lipoprotein apheresis (LA) is an effective tool to reduce cardiovascular events (CVEs) in high-risk patients with elevations of low density lipoprotein-cholesterol (LDL-C) and/or Lipoprotein(a) (Lp(a)). All patients included into this retrospective analysis had experienced CVEs before the start of the LA therapy. We compared personal and lab data in two groups: CVEx/0 ( 60) with no new events during LA therapy, CVEx/1+ ( 48) with at least one new event.

Versatile Electrochemical Sensing Platform for Bacteria.

Bacterial infections present one of the leading causes of mortality worldwide, resulting in an urgent need for sensitive, selective, cost-efficient, and easy-to-handle technologies to rapidly detect contaminations and infections with pathogens. The presented research reports a fully functional chemical-detection principle, addressing all of the above-mentioned requirements for a successful biosensing device. With the examples of Escherichia coli and Neisseria gonorrheae, we present an electrochemical biosensor based on the bacterial expression of cytochrome c oxidase for the selective detection of clinically relevant concentrations within seconds after pathogen immobilization.

Understanding gold nanoparticle dissolution in cyanide-containing solution via impact-chemistry.

The electrochemical dissolution of citrate-capped gold nanoparticles (AuNPs) was studied in cyanide (CN-) containing solutions. It was found that the gold nanoparticles exhibited different dissolution behaviours as ensembles compared to the single particles. At the single particle level, a nearly complete oxidation of 60 nm AuNPs was achieved at concentrations greater than or equal to 35.

Detection of Escherichia coli bacteria by impact electrochemistry.

We report the redox mediated detection of Escherichia coli bacteria at carbon microelectrodes, using the impact electrochemistry technique. By employing N,N,N',N'-tetramethyl-para-phenylene-diamine (TMPD) as redox mediator a concentration dependency for bacteria impacts was observed, whereby its impact frequency is shown to be in good agreement with theoretically predicted values.

Electrochemical Detection of Pathogenic Bacteria-Recent Strategies, Advances and Challenges.

Bacterial infections represent one of the leading causes of mortality worldwide, nevertheless the design and development of rapid, cost-efficient and reliable detection methods for pathogens remains challenging. In recent years, electrochemical sensing methods have gained increasing attention for the detection of pathogenic bacteria, due to their increasingly competitive sensitivity. However, combining sensitivity with cost efficiency, high selectivity and a facile working procedure in a portable device is difficult.

Electrochemical Hg detection at tannic acid-gold nanoparticle modified electrodes by square wave voltammetry.

We report the electrochemical sensing of Hg2+ based on tannic acid capped gold nanoparticle (AuNP@TA) complexes. At optimal conditions using square wave voltammetry, the presented analytical method exhibits a "measurable lower limit" of 100.0 fM.

Electrochemical recognition and quantification of cytochrome c expression in and aerobe/anaerobe using ,,','-tetramethyl--phenylene-diamine (TMPD).

The colorimetric identification of pathogenic and non-pathogenic bacteria in cell culture is commonly performed using the redox mediator ,,','-tetramethyl--phenylene-diamine (TMPD) in the so-called oxidase test, which indicates the presence of bacterial cytochrome c oxidases. The presented study demonstrates the ability of electrochemistry to employ TMPD to detect bacteria and quantify the activity of bacterial cytochrome c oxidases. Cyclic voltammetry studies and chronoamperometry measurements performed on the model organism result in a turnover number, calculated for single bacteria.

Effect of cellobiose supplementation on in vitro fermentation activity and bacterial numbers of porcine inocula.

In this in vitro study, the modified Hohenheim gas test (HGT) was applied to determine fermentation activity and bacterial composition of pig's faecal microbial inoculum using different concentrations of cellobiose. Incubation procedures included normal buffered and osmotic stress conditions (elevated medium salinity). After 24 hr of fermentation, production of gas, ammonia and short-chain fatty acid (SCFA) was measured, and the gene copy numbers of total bacteria, Lactobacillus spp.

Ferrocene-Modified Phospholipid: An Innovative Precursor for Redox-Triggered Drug Delivery Vesicles Selective to Cancer Cells.

Controlled payload release is one of the key elements in the creation of a reliable drug delivery system. We report the discovery of a drug delivery vessel able to transport chemotherapeutic agents to target cancer cells and selectively trigger their release using the electrochemical activity of a ferrocene-modified phospholipid. Supported by in vitro assays, the competitive advantages of this discovery are (i) the simple one step scalability of the synthetic process, (ii) the stable encapsulation of toxic drugs (doxorubicin) during transport, and (iii) the selective redox triggering of the liposomes to harness their cytotoxic payload at the cancer site.

Sec13 Regulates Expression of Specific Immune Factors Involved in Inflammation In Vivo.

The Sec13 protein functions in various intracellular compartments including the nuclear pore complex, COPII-coated vesicles, and inside the nucleus as a transcription regulator. Here we developed a mouse model that expresses low levels of Sec13 (Sec13(H/-)) to assess its functions in vivo, as Sec13 knockout is lethal. These Sec13 mutant mice did not present gross defects in anatomy and physiology.

High-speed scanning electrochemical microscopy method for substrate kinetic determination: application to live cell imaging in human cancer.

Scanning electrochemical microscopy (SECM) is increasingly applied to study and image live cells. Quantitative analyses of biological systems, however, still remain challenging. In the presented study, single human adenocarcinoma cervical cancer cells are electrochemically investigated by means of SECM.

High-speed scanning electrochemical microscopy method for substrate kinetic determination: method and theory.

Scanning electrochemical microscopy (SECM) allows imaging and analysis of a variety of biological samples, such as living cells. Up to now, it still remains a challenge to successfully decouple signals related to topography and reactivity. Furthermore, such delicate samples require careful adjustment of experimental parameters, such as scan velocity.