We evaluated the effect of phytic acid on matrix metalloproteinase (MMP)- or cysteine cathepsin (CC)-mediated dentin degradation. Demineralized dentin beams were divided into five groups (n = 12) and treated with 1%, 2%, or 3% phytic acid or with 37% phosphoric acid. Untreated demineralized beams served as controls. After incubation for 1 or 3 wk, dry mass loss was determined and aliquots of incubation media were analysed for cross-linked telopeptide of type I collagen (ICTP) fragments for MMP-mediated and c-terminal telopeptide of type I collagen (CTX) for cathepsin-k-mediated degradation. The direct effect of phytic acid was evaluated using MMP activity assay. Data were analysed using repeated-measures anova. ICTP releases with 1% and 2% phytic acid treatment were statistically significantly lower than those following phosphoric acid treatment at 3 wk. The CTX release for phytic acid-treated beams at 3 wk was not significantly different from that of untreated control beams, but it was significantly lower than that of phosphoric acid-treated beams. Their MMP activities at 3 wk were not significantly different from those of the controls but they were significantly lower than those seen for phosphoric acid-treated beams. Compared to phosphoric acid, phytic acid treatment resulted in a reduced dentinal host-derived endogenous enzymatic activity and collagen degradation.Partitioning of the genome in meiosis occurs through two highly specialized cell divisions, named meiosis I and meiosis II. Step-wise cohesin removal is required for chromosome segregation in meiosis I, and sister chromatid segregation in meiosis II. In meiosis I, mono-oriented sister kinetochores appear as fused together when examined by high-resolution confocal microscopy, whereas they are clearly separated in meiosis II, when attachments are bipolar. It has been proposed that bipolar tension applied by the spindle is responsible for the physical separation of sister kinetochores, removal of cohesin protection, and chromatid separation in meiosis II. We show here that this is not the case, and initial separation of sister kinetochores occurs already in anaphase I independently of bipolar spindle forces applied on sister kinetochores, in mouse oocytes. This kinetochore individualization depends on separase cleavage activity. Crucially, without kinetochore individualization in meiosis I, bivalents when present in meiosis II oocytes separate into chromosomes and not sister chromatids. This shows that whether centromeric cohesin is removed or not is determined by the kinetochore structure prior to meiosis II.
Vaccine hesitancy poses serious challenges for achieving coverage for population immunity. It is necessary to achieve high COVID-19 vaccination acceptance rates and medical students' coverage as future health care providers. The study aimed to explore the level of COVID-19 vaccine hesitancy and determine the factors and barriers that may affect vaccination decision-making.
A cross-sectional study was carried out among medical students in Tanta and Kafrelsheikh Universities, Egypt. Data collection was done via an online questionnaire during January 2021 from 2133 students.
The majority of the participant students (90.5%) perceived the importance of the COVID-19 vaccine, 46% had vaccination hesitancy, and an equal percentage (6%) either definitely accepted or refused the vaccine. Most of the students had concerns regarding the vaccine's adverse effects (96.8%) and ineffectiveness (93.2%). see more The most confirmed barriers of COVID-19 vaccination were deficient data regarding the vaccine's adverse effects (potential 74.17% and unknown 56.31%) and insufficient information regarding the vaccine itself (72.76%).
The government, health authority decision-makers, medical experts, and universities in Egypt need to work together and make efforts to reduce hesitancy and raise awareness about vaccinations, consequently improving the acceptance of COVID-19 vaccines.
The government, health authority decision-makers, medical experts, and universities in Egypt need to work together and make efforts to reduce hesitancy and raise awareness about vaccinations, consequently improving the acceptance of COVID-19 vaccines.Animal models of invasive fungal infections have been developed and are applied in a huge number of different animal species for a number of research purposes, for example, the study of pathogenesis, defense mechanisms, and therapeutic strategies. From the different models, which in most cases are based on the same fungal species and often the same strain, as in spontaneous human infections, fundamental results and knowledge of the diagnosis, progression, prophylaxis, and therapy have been achieved. However, in all models, one should be critical with respect to mimicking the disease entity of humans, which is often the focus of the research. In many of the models for instance, the time course is different to the one of humans, and in others, the propensity for localization and containment in specific organs does not parallel the situation in humans. Nevertheless, many animal models of invasive mycoses have proven valuable in a number of research areas. With regard to new generations of anti-mycotic drugs, the models play an essential role in demonstrating antifungal activity, as well as in demonstrating the absence of toxic side effects, a critical step which cannot be accomplished by in vitro studies.
To propose a method for voxel-wise estimation of cell radii and volume fractions of two cell populations when they coexist in the same MR voxel using the combination of diffusion-weighted MRI and microstructural modeling.
Microstructure models were investigated using diffusion data simulated with the matrix method for a range of microstructures mimicking tumor tissue with two cell populations, using acquisition parameters available on preclinical scanners. The effect of noise was investigated for a subset of these microstructures. The accuracy and precision of the estimated radii and volume fractions for large and small cells
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were evaluated by comparing the estimates to their true values.see more
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