Background: The nail unit (NU) is a complex structure that performs a number of functions, including protection, defense, manipulation, and palpation. Non-invasive research methods can facilitate the recognition of NU structure and function. Evaporimetry and HF-USG due to their availability of equipment and low research costs seem to be particularly noteworthy, but so far have been assessed to a limited extent. The aim of the presented study was to check the usefulness of TOWL and HF-USG in examination of NU.Materials and Methods: A total of 58 volunteers aged 25–65 years (mean age: 41 ± 10.16 years) were qualified for the study. The subjects did not present symptoms of clinically evident onychopathy and did not suffer from any dermatoses associated with lesions occurring within the NU. Additionally, the patients did not suffer from systemic diseases that could affect NU (including heart, lung, and endocrine diseases). In all volunteers, the measurement of TOWL and 20 MHz ultrasonography [high-frequency ultrasonography (HF-USG)] with the special emphasis on determination of nail plate thickness were performed.Results: Analysis of 464 HF-USG images revealed that the nail plate presented as two hyperechoic, parallel streaks (railway sign) with a linear hypoechoic middle layer between them. Matrix was visualized as a hypoechoic structure with blurred boundaries, mostly within the fourth and fifth fingers and more often in women. We found statistically significant correlations between the type of a finger and the thickness of the nail plate both in the entire study group and taking into account gender. In the dominant hand, the results were r = −0.341; p < 0.001; r = −0.417, p < 0.001; and r = 0.337; p = 0.001 (for the whole group, for women, and for men, respectively). In the non-dominant hand, the results were r = −0.465; p < 0.001; r = −0.493, p < 0.01; and r = −0.503; p < 0.01 (for the whole group, for women, and for men, respectively). There were statistically significant differences in the thickness of the nail plates of the corresponding types of fingers between female and male NUs. Statistically significant correlations were found between the type of a finger and the TOWL value in the whole group and taking into account gender (p < 0.05), except for the non-dominant hand in men. There were no statistically significant differences in the TOWL values of the corresponding types of fingers between male and female NUs (p > 0.05). There was no statistically significant correlation between the TOWL value and the nail plate thickness in any of the tested NUs, apart from the one statistically significant correlation in nd5 (r = 0.390, p = 0.021).Conclusions: To sum up, non-invasive methods, such as HF-USG and TOWL, enable assessment of the NU and are useful in examination of its structure and function. HF-USG shows characteristic elements of NUs that can be distinguished because of differences in their echogenicity. The thickness of the nail plate and TOWL depend on the type of finger, and show a relationship with gender.

Fermented food is a source of microorganisms. Numerous strains present in fermented products have probiotic characteristics. Probiotic strains can reverse dysbiosis due to the ability to modify gut microbiota. Regular consumption of fermented products may positively affect the composition and diversity of the intestinal microbiota. Numerous studies focus on the health effects of fermented dairy products. The range of non-dairy fermented products is large and includes, among others, vegetables, meat, fish, and eggs. The main ingredient and method of fermentation determine the presence and amount of bacterial strains. Lactic acid bacteria (LAB) present in sauerkraut, kimchi, and pickled cucumbers have a positive effect on the immune system activity, lipid metabolism, and anti-carcinogenic activity. The introduction of sauerkraut to the diet of irritable bowel syndrome (IBS) patients improved their quality of life. Soy sauce strains alleviate allergic rhinitis. Other fermented soy products show a beneficial effect on lipid profile or haematological parameters in animal models. Strains present in kombucha have not yet been tested for effects on consumer health. In summary, regular consumption of fermented non-dairy products can have a multidirectional impact on health improvement. However, more studies in this range, especially on appropriate daily intake of fermented food, are necessary to formulate a precise conclusion.

Introduction. Probiotics are live microorganisms which, administered in appropriate amounts, have a beneficial effect on human health. Food products that contain these microorganisms are known as natural probiotics. Probiotic food include the group of dairy products in which fermented milk products are majority. Objective. The aim of the study is to review current data and summarize knowledge on the effects of consumption of dairy probiotics on human health. The review also aims at discussing the potential of these health-supporting microorganisms as a prevention factor against civilization diseases. State of knowledge. Consumption of probiotic food, especially natural dairy probiotic food, may have a positive effect on health due to the presence of probiotic bacteria or by the presence of their metabolites (postbiotics) demonstrating bioactive effects. The intake of these products is associated with the improvement of parameters such as lipid profile, insulin sensitivity, cardiovascular risk parameters, or presents protective effect on bones. Studies show a correlation between the consumption of natural probiotics and reduction in duration of diarrhea or alleviation of the course of inflammatory bowel diseases. Conclusion. The influence of natural dairy probiotics consumption on the state of health has recently been broadly investigated. Regular consumption of these products has shown beneficial effect on gut microbiota and on a wide range of health parameters. However, further studies are necessary to draw a precise conclusion.