Vilmantas Gegzna

Creates compact letter displays (CLDs) for pairwise comparisons from statistical post-hoc tests. Groups sharing the same letter are not significantly different from each other. Supports multiple input formats including results from 'stats' pairwise tests, 'DescTools', 'PMCMRplus', 'rstatix', symmetric matrices of p-values, and data frames. Provides a consistent interface for visualizing statistical groupings across different testing frameworks.

An educational package providing intuitive functions for calculating confidence intervals (CI) for various statistical parameters. Designed primarily for teaching and learning about statistical inference (particularly confidence intervals). Offers user-friendly wrappers around established methods for proportions, means, and bootstrap-based intervals. Integrates seamlessly with Tidyverse workflows, making it ideal for classroom demonstrations and student exercises.

The level of degeneration (LOD) in the human intervertebral disc (IVD) could determine the choice of patient treatment strategy, thus there is a need for methods applicable at a point of care that enable quick medical decisions. In this paper, infrared light absorption, FT-Raman scattering and fluorescence spectroscopy were used to analyse the same specimens from different groups of IVD samples. Samples from the lumbar part of spine of 37 patients (mean age 48.2 years old) were included in the study. The gender distribution was 27 women and 10 men. The distribution by LOD in the Pfirrmann scale was as follows: grade 3 (40.5%), grade 4 (48.6%) and grade 5 (10.8%) were evaluated in our samples. Spectroscopic signals were measured and analysed. Features such as medical condition (LOD), patient’s age and gender were taken into account. All three methods of spectroscopy revealed age-dependent spectroscopic features related to LOD. For the first time a promissing possibility was found to recognize the LOD by fluorescence spectra in human IVD material taking gender and age into account. The findings create a background for the design of equipment and the design of experiment of more advanced clinical trials. FT-IR absorption and FT-Raman scattering spectra demonstrated the age dependences of a few components. The Raman peak at 2707 cm^–1 seems promising for recognition of lumbar IVD LOD, but a higher number of specimens is necessary.

The well-known genotypic and phenotypic diversity of G. vaginalis resulted in its classification into at least four subgroups (clades) with diverse genomic properties. To evaluate the virulence potential of G. vaginalis subgroups, we analyzed the virulence-related phenotypic characteristics of 14 isolates of clade 1, 12 isolates of clade 2, 8 isolates of clade 4 assessing their in vitro ability to grow as a biofilm, produce the toxin vaginolysin, and express sialidase activity. Significant differences in VLY production were found (p = 0.023), but further analysis of clade pairs did not confirm this finding. The amount of biofim did not differ significantly among the clades. Analysis of sialidase activity indicated statistically significant differences among the clades (p < 0.001). Production of active recombinant G. vaginalis sialidase demonstrated the link between the sld gene and enzymatic activity, which may be differentially regulated at the transcriptional level. Statistical classification analysis (random forests algorithm) showed that G. vaginalis clades could be best defined by the profiles of two phenotypic characteristics: sialidase activity and vaginolysin production. The results of principal component analysis and hierarchical clustering suggested that all isolates can be subgrouped into three clusters, the structures of which are determined based on phenotypic characteristics of the isolates. Clade 4 was the most homogenous group, as all isolates were found in the same cluster, which is characterized by low production of all studied virulence factors. Clade 2 isolates were mainly distributed between two clusters, whereas clade 1 isolates were found in all three clusters that were characterized by a distinct profile of phenotypic characteristics. Our findings suggest that G. vaginalis subgroups with different virulence potential might play distinct roles in vaginal microbiota.

The diagnostics of endometrial pathology can be done by obtaining information at the molecular level, e. g. using the autofluorescence-based technique. Thus, for the first time an experimental study was performed on waste material of uterine cavity washing specimens to evaluate suitability of the technique for diagnostics. The specimens were obtained from 32 patients who had a conventional uterine hydrosonography procedure. A portable Nd:YAG 355 nm microlaser was used to excite autofluorescence at the point of care. Various algorithms of multivariate curve resolution and artificial neural networks were utilized for spectra analysis. The spectra were classified according to histological and ultrasound diagnosis. Receiver operating characteristic (ROC) curve analysis was used to make statistical decisions. The results showed that it was possible to distinguish all compared groups: pathologic vs non-pathologic endometrium (sensitivity 97.3 ± 5.2%, specificity 91.7 ± 7%, AUC (area under the ROC curve) 0.96 ± 0.04), malignant endometrium vs endometrial polyps (sensitivity 100 ± 0%, specificity 92.0 ± 10.6%, AUC = 0.98 ± 0.07), and secretory menstrual cycle phase vs proliferative phase (sensitivity 87.5 ± 13.2%, specificity 94.4 ± 7.4%, AUC = 0.88 ± 0.10). To conclude, uterine cavity washing specimens could be used for endometrial pathology recognition using the autofluorescencebased technique in clinical setting. It will possibly speed up the treatment decision making for endometrial pathology.

Objective: Fluorescence is widely investigated and can characterize general changes occurring in the state of the cell and the tissue during physiological and/or pathological processes, but the method has not been adopted for clinical use. We present a photodiagnostic device and a relevant evaluation method fitted to classical screening procedures. This method is based on the discovery of smear content intrinsic fluorescent markers. Background data: Meaningful spectral components of cervical smear samples differ from those measured in the entire live cervix. This article deals with the identification of changes in smear spectra in cervicitis and CIN2+ (cervical intraepithelial neoplasia of the second degree or higher) at 355 nm excitation. Methods: Methods used in the study: microlaser-induced fluorescence spectroscopy of liquid cytology samples and histological evaluation of the biopsies of the same cervix (and/or only cytological evaluation) was performed for 78 cases. The fluorescence spectra of cervical cytology supernatant sediment were approximated with several Gaussian components. The ratios of the area under each Gaussian component to the whole area under the experimental curve were calculated and compared among histological groups by using the Mann–Whitney test and receiver operating characteristic (ROC) analysis. Results: The results of this study are a concise summary of the essential features verified by the data: the spectral regions 402–416 nm and 424–438 nm are important for the discrimination of both normal and CIN2+ groups (in terms of sensitivity, specificity, and positive predictive value). The spectral regions 480–515 nm and 595–625 nm are important for the identification of cervicitis. Conclusions: Cervical smear autofluorescence diagnostics could be useful for cancer screening at the point of care, in a simple cytology laboratory, and for the monitoring of treatment. We suggest possible fluorophores in the smear content.