Application of artificial intelligence in diagnosing COVID-19 disease symptoms on chest X-rays: A systematic review

This systematic review focuses on using artificial intelligence (AI) to detect COVID-19 infection with the help of X-ray images.Methodology: In January 2022, the authors searched PubMed, Embase and Scopus using specific medical subject headings terms and filters. All articles were independently reviewed by two reviewers. All conflicts resulting from a misunderstanding were resolved by a third independent researcher. After assessing abstracts and article usefulness, eliminating repetitions and applying inclusion and exclusion criteria, six studies were found to be qualified for this study.Results: The findings from individual studies differed due to the various approaches of the authors. Sensitivity was 72.59%-100%, specificity was 79%-99.9%, precision was 74.74%-98.7%, accuracy was 76.18%-99.81%, and the area under the curve was 95.24%-97.7%.Conclusion: AI computational models used to assess chest X-rays in the process of diagnosing COVID-19 should achieve sufficiently high sensitivity and specificity. Their results and performance should be repeatable to make them dependable for clinicians. Moreover, these additional diagnostic tools should be more affordable and faster than the currently available procedures. The performance and calculations of AI-based systems should take clinical data into account.     

Correlation between KRAS,NRAS and BRAF mutations and tumor localizations in patients with primary and metastatic colorectal cancer

IntroductionDetection of abnormalities in the KRAS, NRAS and BRAF genes is extremely important for proper qualification of colorectal cancer (CRC) patients for therapy with anti-EGFR (epidermal growth factor receptor) monoclonal antibodies. However, data about prevalence of mutations in these genes, in different localizations of CRC tumors, are limited.Material and methodsWe examined the frequency of mutations in the KRAS, NRAS and BRAF genes in 500 Caucasian CRC patients (200 women and 300 men, median age 66 years). DNA was isolated from formalin-fixed, paraffin-embedded (FFPE) tissues using a Qiagen QIAamp DNA FFPE-kit. Analysis of mutations was carried out using the KRAS/BRAF, NRAS and BRAF Mutation Analysis Kit for Real-Time PCR (EntroGen) with the Cobas 480 real-time PCR apparatus (Roche Diagnostics).ResultsKRAS mutations were detected in 190 (38%) patients, NRAS mutations in 20 (4%) patients, and BRAF mutations in 24 (4.8%) patients. There were no associations between age of CRC patients and frequency of KRAS, NRAS and BRAF gene mutations. These mutations were significantly more often diagnosed in women (55.5%) than in men (41%, p < 0.005). Tumors of the rectum and sigmoideum were the most often observed in both groups of CRC patients – with and without KRAS, NRAS and BRAF gene mutations. However, transverse colon, ascending colon and cecum cancers were the most often affected by mutations.ConclusionsOur study showed that the occurrence of mutations in the KRAS, NRAS and BRAF genes is not accidental and depends on the location of CRC tumors.     

The Role of Resveratrol in Eye Diseases—A Review of the Literature

Resveratrol (3,5,4′-trans-trihydroxystilbene) is a polyphenolic phytoalexin belonging to the stilbene family. It is commonly found in grape skins and seeds, as well as other plant-based foods. Oxidative stress and inflammation play a key role in the initiation and progression of age-related eye disorders (glaucoma, cataracts, diabetic retinopathy, and macular degeneration) that lead to a progressive loss of vision and blindness. Even though the way resveratrol affects the human body and the course of many diseases is still the subject of ongoing scientific research, it has been shown that the broad spectrum of anti-inflammatory and neuroprotective properties of resveratrol has a beneficial effect on eye tissues. In our research, we decided to analyze the current scientific literature on resveratrol, its possible mechanisms of action, and its therapeutic application in order to assess its effectiveness in eye diseases.     

Detection and monitoring toxigenicity of cyanobacteria by application of molecular methods

The aim of this study was early genetic identification of microcystin-producing cyanobacteria and monitoring their toxigenicity by determining toxin concentrations in three Polish lakes throughout the summer of 2004. The assessment of cyanobacterial blooms was carried out in shallow, eutrophic water bodies: Lake Jeziorak, Lake Bninskie, and Sulejow Reservoir. Samples for DNA, phycological, and toxin analyses were collected from July till October. Molecular analysis of the 16S rRNA region was used to detect cyanobacteria in water samples. The microscopic analysis was performed to investigate seasonal variation of phytoplankton. Cyanobacteria, with domination by Microcystis, Planktothrix, and Planktolyngbya were detected during the whole monitoring period in Sulejow Reservoir, Lake Bninskie, and Lake Jeziorak, respectively. The presence and identification of toxic strains in water bodies was studied by PCR amplification of mcy genes in the microcystis synthesis pathway. The presence of the mcyA, mcyB, mcyD, and mcyE genes in water samples indicated the genetic potential to produce microcystins. Toxicity of water samples and microcystin concentrations were established by PPIA and HPLC, respectively. The maximum concentration of microcystins was 11.13 microg/L and 4.67 microg/L in samples dominated by P. agardhii and M. aeruginosa, respectively. Molecular analysis showed that toxigenic strains of cyanobacteria occurred in the three lakes throughout the summer season.     

Analgesic and anticonvulsant activity of new derivatives of 2-substituted 4-hydroxybutanamides in mice

Earlier in vitro studies of the compounds marked as GT27, GT28, GT29 and BM128 revealed their inhibitory action towards murine γ-aminobutyric acid (GABA) transporters (mGAT1-mGAT4). In the present paper, the pharmacological activity of four γ-hydroxybutyric acid (GHB) amide derivatives was investigated. The following procedures were involved: locomotor activity, hot plate and electroconvulsive threshold tests. The compounds' influence on motor coordination was evaluated in the chimney test, as well. Intraperitoneal (i.p.) administration of the GHB derivatives decreased animals' locomotor activity (ED(50) values ranged between 23.79 and 26.37 mg/kg). At a dose of 25 mg/kg (i.p.) the compounds prolonged the nociceptive reaction time latency in the hot plate assay to various degree and GT28 and GT29 were the most potent ones in this respect. Their analgesic efficacy was particularly pronounced 30 min after their administration [percent of maximal possible effect (%MPE) = 16.93 and 22.72, respectively]. The investigated GHB derivatives, except for GT29 at 100 mg/kg, increased the electroconvulsive threshold by approximately 4-11 mA as compared to the vehicle-treated mice. In the chimney test they impaired the animals' motor coordination to various degree. We suggest further investigations of the compounds to estimate their biological activity.     

Polyaniline and Polyaniline-Based Materials as Sorbents in Solid-Phase Extraction Techniques

Polyaniline (PANI) is one of the best known and widely studied conducting polymers with multiple applications and unique physicochemical properties. Due to its porous structure and relatively high surface area as well as the affinity toward many analytes related to the ability to establish different types of interactions, PANI has a great potential as a sorbent in sample pretreatment before instrumental analyses. This study provides an overview of the applications of polyaniline and polyaniline composites as sorbents in sample preparation techniques based on solid-phase extraction, including conventional solid-phase extraction (SPE) and its modifications, solid-phase microextraction (SPME), dispersive solid-phase extraction (dSPE), magnetic solid-phase extraction (MSPE) and stir-bar sorptive extraction (SBSE). The utility of PANI-based sorbents in chromatography was also summarized. It has been shown that polyaniline is willingly combined with other components and PANI-based materials may be formed in a variety of shapes. Polyaniline alone and PANI-based composites were successfully applied for sample preparation before determination of various analytes, both metal ions and organic compounds, in different matrices such as environmental samples, food, human plasma, urine, and blood.     

Stability Analysis of Thin-Walled Perforated Composite Columns Using Finite Element Method

Open holes or cut-outs have been commonly used in composite structures for various engineering purposes. Those elements often demand perforation especially for weight reduction and to ease maintenance and servicing operations, for example, in aircraft wing ribs. This work presents a numerical study of the stability behavior of composite perforated columns subjected to a compressive load. Profiles were made of CFRP laminate and weakened by three types of cut-out. Four parameters, spacing ratio S/D₀, opening ratio D/D₀, hole shape and arrangement of layers, were selected to check their effect on the buckling load and postbuckling behavior of the tested channel profiles. To carry out the numerical analysis, the Abaqus software was used. The results obtained during the analysis helped to identify the best combination of tested parameters to obtain the highest critical load. The performed analysis show that the columns’ behavior is sensitive to configuration of composite, opening ratio and hole shape.     

Synthesis and Structure–Activity Relationship of 2,6-Disubstituted Thiosemicarbazone Derivatives of Pyridine as Potential Antituberculosis Agents

In this study, six new 2,6-disubstituted thiosemicarbazone derivatives of pyridine were synthesized (4–9), and their tuberculostatic activity was evaluated. All of them showed two- to eightfold higher activity (minimum inhibitory concentration (MIC) 0.5–4 µg/mL) against the resistant strain compared with the reference drug. Compounds 5 and 7, which contained the most basic substituents—pyrrolidine and piperidine—in their structure, strongly inhibited the growth of the standard strain (MIC 2 µg/mL). Furthermore, the same derivatives exhibited activity comparable to that of the reference drugs against some types of Gram-positive bacteria (MIC 0.49 µg/mL) and showed no cytotoxicity (IC50 > 50 µg/mL) in HaCaT cells. The zwitterionic structure of each compound was determined using X-ray crystallography. Absorption, distribution, metabolism, and excretion analyses showed that all compounds are good drug candidates. Thus, compounds 5 and 7 were identified as leading structures for further research on antituberculosis drugs with extended effects.