Catalogue Search | MBRL
Are you sure you want to remove the book from the shelf?
{{itemTitle}}
230
result(s) for
"Michalak, Katarzyna"
Sort by:
Real Domestic Hot Water Consumption in Residential Buildings and Its Impact on Buildings’ Energy Performance—Case Study in Poland
A building’s energy consumption is assessed considering the energy required for heating, cooling, lighting, and domestic hot water (DHW). Methodologies used to calculate energy certificates in European Union countries consider hot water consumption rates per person or per heated (floor) area, giving wide-ranging values (35–88 dm3/person/day). Using extreme parameters, it is possible to obtain a primary energy index that meets the legal requirements, although unrealistically large proportions of domestic hot water use relative to the total energy balance of the building may marginalize the influence of other components, such as fluctuations in heating, ventilation, or lighting. In the current work, the DHW consumption of three residential buildings was measured to verify the energy consumption for hot water preparation. Investigations were conducted based on the consumption of natural gas for DHW preparation. Experimentally obtained water consumption rates were determined per m2 of a dwelling and per person living in the building. The calculated indicators (0.85 ± 0.005 dm3/m2/day and 27.4 ± 1.4 dm3/person/day) were lower than those used for energy certifications of buildings. The experimentally obtained indicators were used in further theoretical energy assessments of six residential buildings. By adopting the designated indicators, the analyzed buildings met the legally required primary energy value (<70 kWh/m2/year) when using natural gas as a heat source. Applying more realistic DHW consumption values resulted in more accurate energy certifications.
Journal Article
Anti-Acne Action of Peptides Isolated from Burdock Root—Preliminary Studies and Pilot Testing
This work aimed to study the anti-bacterial, anti-biofilm and anti-oxidant potential effects of low molecular weight (LMW) peptides (Br-p) isolated from burdock (Arctium lappa L.) roots. We conducted a preliminary study to exclude or confirm the antibiotic activity of the LMW peptides fraction of this plant. Br-p were isolated using gel filtration and a 10 kDa cut-off membrane. The obtained peptides were identified by MALDI TOF/TOF. Antibacterial activity was tested against acne strains using diffusion tests, MIC and MBC. The fibroblast cytotoxicity of Br-p was tested, and the selectivity index (SI) value was determined. The fraction of 46 Br-p peptides isolated from burdock root with a molecular weight below 5000 Da and theoretic pI (isoelectric point) of 3.67–11.83 showed a narrow spectrum of activity against Gram-positive acne bacterial strains. One of the Br-p peptides assessed on MALDI RapidDeNovo was LRCDYGRFFASKSLYDPLKKRR cationic peptide. It was analogous to that contained in A. lappa protein, and theoretically it was matched as a peptide with antibiotic nature. Br-p did not show toxicity to fibroblasts in the tested concentration up to 10 mg/mL, obtaining CC50 10 mg/mL. The SI value for the tested Propionibacterium strains ranged from 160 to 320. Finally, an active dressing based on chitosan/alginate/genipin was prepared using freeze-drying. The formed dressing was evaluated for its anti-acne activity. To sum up: preliminary biological studies confirmed the anti-acne properties of the isolated peptide fraction from burdock root and pointed to the possibility of using it to create an active dressing on the skin.
Journal Article
Mild chronic hypoxia and the brain: an ambiguous relationship
Mild hypoxia is a common condition encountered in various situations, such as high-altitude living, respiratory diseases, anaemia, and certain cardiovascular disorders. At the same time, mild hypoxia often goes unnoticed and can lead to long-term brain impairments. Understanding the subtle effects of mild hypoxia on the brain is essential for early diagnosis and intervention to prevent serious neurological and psychiatric complications. The pathophysiology of mild chronic hypoxia is complex; nevertheless, based on the literature, two main pathways can be distinguished. The first involves the direct effects of mild hypoxia on the brain and spinal cord, while the second involves the influence of enhanced systemic inflammation. In this narrative review, we discuss the current understanding of the effects of mild hypoxia on brain metabolism, cellular models, perfusion, the blood–brain barrier (BBB), the blood–spinal cord barrier (BSCB) and the brain-cerebrospinal fluid barrier (BCSFB). We explore the intricate relationship between peripheral inflammation induced by hypoxia and the BBB/BSCB/BCSFB, shedding light on the underlying mechanisms and their potential implications for central nervous system health.
Graphical abstract
Journal Article
The influence of CD26+ and CD26− fibroblasts on the regeneration of human dermo-epidermal skin substitutes
CD26, also known as dipeptidyl peptidase IV (DPPIV), is a multifunctional transmembrane protein playing a significant role in the cutaneous wound healing processes in the mouse skin. However, only scarce data are available regarding the distribution and function of this protein in the human skin. Therefore, the aim of this study was to investigate the impact of CD26 deficiency in human primary fibroblasts on the regeneration of human tissue-engineered skin substitutes in vivo. Dermo-epidermal skin analogs, based on collagen type I hydrogels, were populated either with human CD26
+
or CD26
knockout
fibroblasts and seeded with human epidermal keratinocytes. These skin substitutes were transplanted onto the back of immune-incompetent rodents. Three weeks post-transplantation, the grafts were excised and analyzed with respect to specific epidermal and dermal maturation markers. For the first time, we show here that the expression of CD26 protein in human dermis is age-dependent. Furthermore, we prove that CD26
+
fibroblasts are more active in the production of extracellular matrix (ECM) both in vitro and in vivo and are necessary to achieve rapid epidermal and dermal homeostasis after transplantation.
Journal Article
Characterization of M1 and M2 polarization of macrophages in vascularized human dermo-epidermal skin substitutes in vivo
Aims and objectivesVascularized bio-engineered human dermo-epidermal skin substitutes (vascDESS) hold promise for treating burn patients, including those with severe full-thickness wounds. We have previously shown that vascDESS promote wound healing by enhanced influx of macrophages and granulocytes. Immediately following transplantation, macrophages infiltrate the graft and differentiate into a pro-inflammatory (M1) or a pro-healing M2 phenotype. The aim of this study was to characterize the activation state of macrophages infiltrating skin transplants at distinct time points following transplantation.MethodsKeratinocytes and the stromal vascular fraction (SVF) were derived from human skin or adipose tissue, respectively. Human SVF containing both endothelial and mesenchymal/stromal cells was used to generate vascularized dermal component in vitro, which was subsequently covered with human keratinocytes. Finally, vascDESS were transplanted on the back of immuno-incompetent rats, excised, and analyzed after 1 and 3 weeks using immunohistological techniques.ResultsA panel of markers of macrophage M1 (nitric oxide synthase: iNOS) and M2 (CD206) subclass was used. All skin grafts were infiltrated by both M1 and M2 rat macrophages between 1–3 weeks post-transplantation. CD68 (PG-M1) was used as a pan-macrophage marker. The number of CD68+CD206+ M2-polarized macrophages was higher in 3-week transplants as compared to early-stage transplants (1 week). In contrast, the number of CD68+iNOS+ M1 cells was markedly decreased in later stages in vivo.ConclusionsMacrophages exhibit a heterogeneous and temporally regulated polarization during skin wound healing. Our results suggest that the phenotype of macrophages changes during healing from a more pro-inflammatory (M1) profile in early stages after injury, to a less inflammatory, pro-healing (M2) phenotype in later phases in vivo.
Journal Article
Proteomic Analysis of Tear Films in Healthy Female and Male Dogs Using MALDI-TOF (Matrix Assisted Laser Desortion/Ionization Time-of-Flight) Mass Spectrometry
This study investigates sex-related differences in the tear film proteomes of healthy male and female dogs using MALDI-TOF mass spectrometry. Tear samples from 22 dogs (11 males, 11 females) were analyzed using 2D electrophoresis, revealing 446 protein spots, with 8 showing statistically significant differential expression. Seven proteins, including TIMP-2, PFK, and Annexin A13, were upregulated in females, while IL-33 was higher in males. These differences indicate potential hormonal influences on tear film composition. The results highlight molecular variations that may be relevant to ocular physiology and could contribute to identifying non-invasive diagnostic biomarkers. This study provides baseline data for future research on sex-related differences in tear film composition in dogs.
Journal Article
In Vitro Assessment of Selected Postbiotic Substances Against Methicillin-Resistant and Methicillin-Susceptible Staphylococcus spp. and Mammaliicoccus spp. of Bovine Mastitis Origin
The growing problem of antibiotic resistance poses one of the greatest threats to modern medicine, making the search for new, alternative strategies to treat bacterial infections a matter of priority. The aim of the study was to evaluate the antimicrobial activity of selected postbiotic substances (PS) and nisin against methicillin-susceptible (MS) and methicillin-resistant (MR) strains of coagulase-negative staphylococci (NAS) and mammaliicocci. The study was conducted on 24 strains of coagulase-negative staphylococci and mammaliicocci isolated from milk collected from Holstein-Friesian (HF) cows with subclinical mastitis. In vitro, PS/EMo (100–400 AU/mL) and PS/Eas (100–200 AU/mL) were the most effective, inhibiting the growth of all MS and MR strains of NAS and Mammaliicoccus spp. (100.0%). A high percentage of strains were also sensitive to postbiotic substances produced by Lactococcus lactis subsp. lactis PS/MK2/8 (400–1600 AU/mL), PS/MK1/3 (100–400 AU/mL), and nisin (100–25,600 AU/mL), both in MR strains (94.1%, 82.4%, 88.2%, respectively) and in MS strains (100.0%, 85.7% and 100%, respectively). PS/Esach (100–25,600 AU/mL) inhibited the growth of all strains, including the mecA gene-positive mammaliicocci strains (100.0%), but was slightly less effective against the MS strains (64.7%). The lowest activity was observed with postbiotic substances produced by Enterococcus faecium, PS/4231 (100–1600 AU/mL) and PS/9296 (100–6400 AU/mL), which inhibited the growth of 3 out of 17 MR strains (17.65%). Among the Mammaliicoccus strains with the mecA gene, postbiotic substances derived from strains PS/4231 and PS/9296 inhibited the growth of 42.9% and 28.6% of the strains, respectively. Four tested strains were sensitive to all postbiotic substances (MSC9, MSC11, MSC12 and SCH3). This study confirms that postbiotic substances and nisin inhibit the growth of staphylococci isolated from the milk of cows with subclinical mastitis, including methicillin-resistant strains.
Journal Article
Who will keep patients safe? The largest multi-centre survey of healthcare students exposes critical gaps in radiation safety education
The increasing use of ionising radiation in medical diagnostics highlights the need for adequate education of future healthcare professionals in radiation protection. This study aimed to assess the level of radiation safety knowledge among healthcare students across different disciplines and years of study.
A cross-sectional survey was conducted among 1,161 students from three Polish medical universities, representing medicine, nursing, radiography, physiotherapy, and paramedic programmes. The questionnaire evaluated knowledge of radiation protection principles, identification of imaging modalities involving ionising radiation, and estimation of relative radiation doses.
The mean percentage of correct answers was 30.1% (SD = 13.9%), indicating generally low levels of knowledge. Fifth-year students achieved the highest scores (41.7%), while fourth-year students performed the worst (23.4%). Physiotherapy students obtained the highest mean scores (36.7%), whereas paramedic students scored the lowest (25.9%). Significant differences were observed between years of study and fields of study (p < 0.001), although effect sizes were small. No significant differences were found between universities (p = 0.063). Students performed best in identifying imaging modalities and worst in radiation dose estimation. Notably, 21% of respondents reported no interest in radiation protection.
Healthcare students demonstrate insufficient knowledge of radiation protection, with only limited improvement across years of study. These findings highlight the need for structured, curriculum-integrated education to improve awareness and safe use of ionising radiation.
Journal Article
Menstrual Cycle Phase Influences Cognitive Performance in Women and Modulates Sex Differences: A Combined Longitudinal and Cross-Sectional Study
Sex hormones’ and menstrual cycle’s effects on cognitive performance remain unclear. This study examined cognitive differences between women across menstrual cycle phases, sex differences between women and men, and hormone–cognition associations. In total, 71 healthy young adults, aged 20–36 (42 women, 29 men), completed standardised cognitive tests measuring attention, processing speed, working memory, and visuospatial abilities. Women were tested twice: during menstrual (low-oestradiol) and pre-ovulatory (high-oestradiol) phases; men once. Hormone levels (oestradiol, progesterone, testosterone) were measured in blood samples via electrochemiluminescence immunoassay (ECLIA). Two analytical strategies were used: (1) within-subject analysis comparing women between phases, and (2) between-group comparison across three groups—women in menstrual phase, pre-ovulatory phase, and men. Women performed better during pre-ovulatory versus menstrual phase in working memory (Digit span forward: p = 0.04; Digit span backwards max: p = 0.02) and attention switching (Trail Making Test B: p = 0.01). Sex differences in processing speed were observed only during the menstrual phase (Trail Making Test A: p = 0.03; Stroop B: p = 0.04), but not in the pre-ovulatory phase. Positive correlations between oestradiol/progesterone and cognitive performance were found in men, while complex bidirectional relationships emerged in women during the menstrual phase only. Testosterone showed no significant correlations. These findings highlight hormonal status effects on cognitive sex differences.
Journal Article