Universidade Federal do Rio Grande do Sul

Arterial hypertension has been linked to cognitive decline, potentially through cerebrovascular alterations and associations with Alzheimer's disease. A positive correlation between elevated serum cholesterol levels and cognitive impairment has been observed. However, the impact of hypercholesterolemia on cognitive decline in both hypertensive rats and patients remains unclear. This study aimed to test the hypothesis that hypercholesterolemia exacerbates cognitive decline in hypertensive rats and human patients. Spontaneously hypertensive rats (SHR) with diet-induced hypercholesterolemia underwent behavioral testing to assess recognition, spatial, and working memory. In patients with stage 2 hypertension, cognitive function was assessed using the Mini Mental State Examination (MMSE) and the Montreal Cognitive Assessment (MoCA) instruments. In SHRs, hypercholesterolemia did not alter cognitive performance. Treatment of SHR with amlodipine or captopril decreased arterial pressure; however, this reduction did not improve cognition performance. The MMSE and MoCA, respectively, revealed cognitive impairment in 87.1 and 97.6% of the hypertensive patients. Nevertheless, no significant differences were found in the mean scores between hypertensive patients with and without hypercholesterolemia. No significant correlation was observed between cognitive scores and the use of antihypertensive or lipid-lowering agents. These observations provide evidence that hypercholesterolemia does not exacerbate cognitive impairment in hypertension. Furthermore, our current findings support the hypothesis that antihypertensive treatment, in the absence of strict blood pressure control, may be insufficient to prevent hypertension-related cognitive decline.

• Saturation with carbon dioxide nanobubbles increases concentration and stability • Salt content influences carbon dioxide concentration and stability in dispersions • Nanobubble saturation of growth media results in higher concentration and stability The application of nanobubbles (NBs) in materials research, water treatment, and chemical reactions is well documented, primarily due to their high stability, longevity, and enhanced mass transfer rates. Recently, oxygen and air nanobubbles have been employed in enhancing algal and plant growth. However, data on carbon dioxide nanobubbles remain scarce, particularly regarding their effects on concentration and retention. In this work, carbon dioxide was dissolved into aqueous solutions with varying salt concentrations, and the flow was depressurized through a needle valve to generate NBs dispersions. Particle number and carbon dioxide concentration were analyzed over a 10-day period and compared with a control solution generated via bubbling. The dispersions exhibited significant NBs concentrations and, more importantly, higher carbon dioxide levels than the bubbling solution. The highest concentrations were observed in 1 mM NaCl and distilled water, corresponding to increases of 136% and 97%, respectively. All dispersions maintained superior concentrations compared to the control. Furthermore, the dispersions retained elevated carbon dioxide levels for an average of five additional days relative to the bubbling solution. Finally, the experimental data were used to fit exponential models describing the evolution of the dispersions. These models revealed both the influence of the saturation methodology and the trade-off between salinity, particle size, and carbon dioxide retention. Overall, the results demonstrate that this methodology provides advantages over conventional carbon dioxide delivery strategies and may contribute to process optimization in algal biomass production.

Yerba mate (Ilex paraguariensis A. St.-Hil.) is a South American native plant whose leaves are used to produce mate, a traditional hot water infusion. The species is rich in secondary metabolites of economic interest and grows naturally in acidic, low-fertility soils where aluminum (Al) is highly bioavailable. However, the influence of Al on secondary metabolism and infusion composition is poorly understood. We cultivated I. paraguariensis in a hydroponic system with increasing Al concentrations. Plant morphology and photosynthesis parameters were not affected, while reactive oxygen species levels and antioxidant enzymatic activity increased. The concentration of secondary metabolites in the infusion, such as caffeine, chlorogenic acid, and flavonoids, exhibited compound-specific changes. Aluminum was detected in the infusion, but its concentration remained similar across treatments, suggesting that external Al supply does not necessarily transfer to the beverage. These findings indicate that I. paraguariensis is Al tolerant, and that Al modulates yerba mate oxidative metabolism, altering infusion composition without impairing physiological parameters.

Wild fish populations face growing threats from anthropogenic activities, climate change, and natural disasters. Aquatic germplasm banking is a vital strategy for preserving genetic diversity and supporting sustainable aquaculture. This study proposes a sequential, decision-guided framework for developing species-specific sperm cryopreservation protocols, applied here to the endangered Pogonias courbina, listed as endangered in Brazil and vulnerable by the IUCN. A series of experiments was conducted to identify optimal conditions for thawing (26°C for 14s), equilibration time (10min), extenders (HBSS, 3% glucose, 5% glucose), and both permeable (dimethyl sulfoxide, propylene glycol, dimethylformamide, ethylene glycol) and non-permeable cryoprotectants (glucose, fructose, sucrose, trehalose, skimmed powdered milk, egg yolk). Sperm quality was assessed using Computer-Assisted Sperm Analysis (CASA). Three treatments with the highest post-thaw motility (MOT) were selected to fertilize oocytes from two hormonally-induced females. No significant difference was observed between sperm from wild and farmed males. The best kinetic parameters and fertilization rates were obtained using the combination of HBSS +10% DMSO +5% egg yolk (MOT: 71.8%). Based on these findings, we propose practical recommendations regarding extender selection, equilibration time, cryoprotectant combinations, and thawing conditions that support high post-thaw viability and successful fertilization. This is the first study to report successful artificial reproduction of P. courbina using cryopreserved sperm, establishing a reproducible protocol that can be applied for captive breeding, restocking, and germplasm banking. The proposed framework offers a generalizable approach for developing cryopreservation protocols in fish species.

This study investigated the association between genetic variants and the occurrence of oral mucositis (OM) in pediatric patients with acute lymphoblastic leukemia (ALL) and lymphoma undergoing chemotherapy (CT). A retrospective observational longitudinal study was conducted, with daily assessment of OM using the World Health Organization scale and blood samples collected for DNA extraction. Genetic variants were analyzed through next-generation sequencing, using a gene panel focused on 67 coding regions within 20 genes. Sixty-four pediatric patients were evaluated during 392 cycles of CT, with the most commonly used protocols being doxorubicin (DOXO) (34.2%), methotrexate (MTX) (27.8%), and cyclophosphamide (CTX) (17.3%). Approximately 65.8% of patients developed some degree of mucositis, with 34.7% showing ulcerative OM (Grades 2 or 3) and 9.2% presenting severe OM (Grade 3). Associations between genetic variants and OM were identified in MTX cycles (ABCC2, ABCC4, and GSTM1), CTX cycles (ABCC6, HSP90AA1, and ABCC1), and DOXO cycles (ABCC1, CYP2A7, and MTHFR). This study suggests potential future treatment strategies, with the possibility of increasing efficacy, reducing toxicity, and improving survival rates in pediatric oncology patients.

To describe and analyze the microscopic morphometry of the mastoid segment of the human facial nerve in the region of the stylomastoid foramen, in different age groups of elderly individuals. Eighteen blocks of temporal bones from cadavers aged between 63 and 94 years old were used and divided into 3 age groups: 60-70, 71-80 and over 80-years-old. The nerve was collected, fixed in a glutaraldehyde and paraformaldehyde solution and then subjected to dehydration and resin embedding processes. Semi-thin cross-sectional sections (1 μm) were obtained using an ultramicrotome and stained with toluidine blue. Histological images were captured and analyzed using Zen 2.6 software. The variables were described by mean and standard deviation and compared between age groups (SPSS; p < 0.05). The Cross-Sectional Area (CSA) of the nerve, diameter of the myelinated fiber, CSA of the myelinated fiber, thickness of the myelin sheath and percentage of total area occupied by myelinated fibers were lower in the groups with older ages, with significant differences among all age groups (p < 0.001). The total number of myelinated fibers and density remained constant and did not present significant differences between age groups. CSA and axon diameter decreased at older ages, with significant differences only between the second and third groups (p < 0.001). The degree of myelination (g ratio) and the percentage of area occupied by the endoneurium, unmyelinated fibers and degenerating tissue were higher in the older age groups (p < 0.001). In the older age groups, there was an increase in the percentage of myelinated fibers with lower CSA and a reduction in the percentage of myelinated fibers with higher CSA. The results indicate that the facial nerve presents morphometric variations suggestive of neurodegeneration, associated with aging. Level V.