The aim of this study was to investigate the therapeutic potential of resveratrol in combination with cisplatin on the inhibition of tumour angiogenesis, growth, and macrophage polarization in mice ...bearing the solid form of an Ehrlich ascites tumour (EAT) that were exposed to whole-body hyperthermia treatment. In addition, we investigated whether a multimodal approach with hyperthermia and resveratrol could abolish cisplatin resistance in tumour cells through the modulation of histone deacetylase (HDAC) activity and levels of heat shock proteins (HSP70/HSP90) and contribute to the direct toxicity of cisplatin on tumour cells. The tumour was induced by injecting 1 × 10
EAT cells subcutaneously (
) into the thighs of Balb/c mice. The mice were treated with resveratrol
for five consecutive days beginning on day 2 after tumour injection and/or by injecting cisplatin intraperitoneally (
) at a dose of 2.5 mg/kg on days 10 and 12 and at a dose of 5 mg/kg on day 15. Immediately thereafter, the mice were exposed to systemic hyperthermia for 15 min at a temperature of 41 °C. The obtained results showed that the administration of resveratrol did not significantly contribute to the antitumour effect of cisplatin and hyperthermia, but it partially contributed to the immunomodulatory effect and to the reduction of cisplatin toxicity and to a slight increase in animal survival. This treatment schedule did not affect microvessel density, but it inhibited tumour growth and modulated macrophage polarization to the M1 phenotype. Furthermore, it abolished the resistance of tumour cells to cisplatin by modulating HDAC activity and the concentration of HSP70 and HSP90 chaperones, contributing to the increased lifespan of mice. However, the precise mechanism of the interaction between resveratrol, cisplatin, and hyperthermia needs to be investigated further.
Limbal stem cells (LSCs) are crucial for the regeneration of the corneal epithelium in patients with limbal stem cell deficiency (LSCD). Thus, LSCs during cultivation in vitro should be in highly ...homogeneous amounts, while potency and expression of stemness without tumorigenesis would be desirable. Therefore, further characterization and safety evaluation of engineered limbal grafts is required to provide safe and high-quality therapeutic applications.
After in vitro expansion, LSCs undergo laboratory characterization in a single-cell suspension, cell culture, and in limbal grafts before transplantation. Using a clinically applicable protocol, the data collected on LSCs at passage 1 were summarized, including: identity (cell size, morphology); potency (yield, viability, population doubling time, colony-forming efficiency); expression of putative stem cell markers through flow cytometry, immunofluorescence, and immunohistochemistry. Then, mitotic chromosome stability and normal mitotic outcomes were explored by using live-cell imaging. Finally, impurities, bacterial endotoxins and sterility were determined.
Expression of the stemness marker p63 in single-cell suspension and in cell culture showed high values by different methods. Limbal grafts showed p63-positive cells (78.7 ± 9.4%), Ki67 proliferation (41.7 ± 15.9%), while CK3 was negative. Impurity with 3T3 feeder cells and endotoxins was minimized. We presented mitotic spindles with a length of 11.40 ± 0.54 m and a spindle width of 8.05 ± 0.55 m as new characterization in LSC culture. Additionally, live-cell imaging of LSCs (n = 873) was performed, and only a small fraction < 2.5% of aberrant interphase cells was observed; 2.12 ± 2.10% of mitotic spindles exhibited a multipolar phenotype during metaphase, and 3.84 ± 3.77% of anaphase cells had a DNA signal present within the spindle midzone, indicating a chromosome bridge or lagging chromosome phenotype.
This manuscript provides, for the first time, detailed characterization of the parameters of fidelity of the mitotic process and mitotic spindle morphologies of LSCs used in a direct clinical application. Our data show that p63-positive CK3-negative LSCs grown in vitro for clinical purposes undergo mitotic processes with extremely high fidelity, suggesting high karyotype stability. This finding confirms LSCs as a high-quality and safe therapy for eye regeneration in humans.
This study assesses the knowledge, practices, and attitudes of medical staff in intensive care units (ICUs) regarding oral hygiene care for critically ill, bedridden patients.
A cross-sectional study ...included 65 employees from the Intensive Care Units of the Sestre Milosrdnice Clinical Hospital Centre (CHC SM) and the Clinic for Anesthesiology and Intensive Care at the University Clinical Hospital Centre Zagreb (CHC ZG). A self-administered questionnaire was used to assess knowledge, methods, frequency, and attitudes towards oral care for mechanically ventilated patients. The data were examined through descriptive statistical methods, presented in terms of proportions (percentages). For the purpose of comparing the feedback across the two hospital centers and different educational backgrounds, the Chi-square and Fisher's exact tests were employed.
Results of a survey of 65 participants (18 from CHC SM and 47 from CHC ZG) revealed a notable disparity in oral hygiene knowledge, with graduate nurses displaying the highest proportion of adequate knowledge (100%) and regular nurses showing the least (30.3%) (p<.001). Although the execution of oral care practices did not vary significantly among the groups, graduate nurses performed oral care more frequently (80% vs. baccalaureate technicians 33.33% and nurses 57.6%, three or more times a day) and demonstrated better proficiency in both mechanical (p=.005) and chemical (p<.001) biofilm management compared to their counterparts. No significant difference was observed in the delivery of oral care to orotracheally intubated patients across different educational levels (p=.127). However, a marked difference was noted in the perception of being adequately trained for such care, with nurses feeling less prepared (12.1%, p<.001). Despite these variances, all respondents recognized the importance of oral hygiene, thus showing a strong dedication to oral health care.
This study highlights variability in ICU oral hygiene practices and points to the importance of standardized care protocols and improved training for healthcare staff.
The aim of the present study was to evaluate genome damage induced in peripheral blood lymphocytes of Croatian health care workers occupationally exposed to cytotoxic drugs. A comprehensive ...multi-biomarker approach using the alkaline comet assay and cytogenetic endpoints (analysis of structural chromosome aberrations, SCE assay, lymphocyte proliferation kinetics and cytokinesis-block micronucleus assay) was employed. The study included two populations of subjects: 50 health care workers occupationally exposed to cytotoxic drugs and 50 control subjects matched in age, gender and smoking habit. An investigation regarding the handling practice with cytotoxic drugs was conducted in parallel. Results obtained indicate high exposure levels at workplace that should be reduced. The values recorded among the occupationally exposed subjects were as follows: mean comet tail length: 17.46±0.08
μm; the incidence of long-tailed nuclei: 54.68±3.93%; 4.48±0.33 structural chromosome aberrations per 200 cells; 5.81±0.04 SCE per 50 cells; 29.28±2.21% of high-frequency cells; proliferation rate index: 1.97±0.12; and 16.32±0.85 micronuclei per 1000 binuclear cells. All these values indicated higher levels of DNA and cytogenetic damage compared to the general population. Obtained results also confirmed that the frequency of long-tailed nuclei in the alkaline comet assay represents a helpful complement to other well-established comet parameters. The age of subjects and smoking habit significantly influenced the values of both comet and cytogenetic endpoints. Overall results of this study confirmed that handling cytotoxic drugs without appropriate safety precautions involves a potential genotoxic risk for exposed subjects. Before a strict monitoring of exposure levels on each workplace becomes a standard practice in Croatian hospitals, cytogenetic surveillance of exposed workers is also recommended, at least in cases of accidental exposure.
The radioprotective effects of water-soluble derivate of propolis (WSDP) collected in Croatia, and single flavonoids, caffeic acid, chrysin and naringin in the whole-body irradiated CBA mice were ...investigated. Irradiation was performed using a γ-ray source (60Co), and absorbed doses were 4 and 9 Gy. The efficiency of test components was evaluated when given intraperitoneally (i.p.) at dose of 100 mg kg−1 for 3 consecutive days before and/or after irradiation. Moreover, possible genotoxic effects of all test components were assessed on non-irradiated animals. The higher efficiency of test components was observed when given preventively. The results suggest that propolis and related flavonoids given to mice before irradiation protected mice from lethal effects of whole-body irradiation and diminish primary DNA damage in their white blood cells as detected by the alkaline comet assay.
This in vitro study aimed at investigating the possible radioprotective effects of natural substances propolis and quercetin on γ-irradiated human white blood cells. The levels of primary DNA damage ...were studied by the alkaline comet assay, while the cytogenetic damage was evaluated using the analysis of structural chromosome aberration and cytokinesis-block micronucleus assay. The results obtained by all endpoints indicate acceptable toxicity profiles of propolis and quercetin in vitro, and also confirmed their radioprotective abilities. Propolis was found to be more effective in diminishing the levels of primary and more complex cytogenetic DNA damage in gamma-irradiated white blood cells. Data gathered in present study support the use of propolis and quercetin as non-toxic protective substances. However, to clarify the underlying mechanisms of their cyto/radioprotective activities, additional studies are necessary at both in vitro and in vivo levels.
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