High-intensity interval training ameliorates spatial and recognition memory impairments, reduces hippocampal TNF-alpha levels, and amyloid-beta peptide load in male hypothyroid rats.

Thyroid hormones are critical for healthy brain functions at every stage of life. Hypothyroidism can cause severe cognitive dysfunction in patients who do not receive adequate treatment. Although thyroid hormone replacement alleviates cognitive decline in hypothyroid patients, there are studies showing that there is no complete recovery. The aim of this study was to investigate the effects of high-intensity interval training (HIIT) in hypothyroid rats on spatial and recognition memory, neuroinflammation, amyloid-beta load and compare these effects with T3 replacement. Hypothyroidism was induced and maintained by administration of 6-n-propyl-2-thiouracil (PTU) with their drinking water to 6-weeks-old male Sprague-Dawley rats for 7 weeks. The animals exercised in the treadmill according to the HIIT protocol for four weeks. T3 was injected intraperitoneally daily during the last two weeks of the study. All animals performed in the elevated plus maze test, Morris water maze test, novel object recognition test, and rotarod motor performance test in the last week of the study and then the animals were sacrificed. Amyloid beta (1-42) and TNFα levels were measured in the prefrontal cortex and hippocampus by ELISA. Anxiety-like behaviors did not significantly differ between groups. T3 replacement with or without HIIT increased motor performance in PTU-treated rats. HIIT and/or T3 replacement increased the exercise performance. HIIT and/or T3 replacement alleviated spatial and recognition memory impairments and normalized TNFα and amyloid-beta levels in the hippocampus in hypothyroid rats. In summary, regular physical exercise may have potential benefits in preserving cognitive functions in hypothyroid patients.

The ameliorative effect of midazolam on empathy-like behavior in old rats.

Although studies suggest that cognitive functions in the elderly are impaired, elderly people tend to be more successful and wiser in solving emotional problems. In empathy-like behavior models, the observer rat rescues the distressed cage mate by displaying emotional and cognitive ability. The aim of the study was to investigate the changes in empathy-like behavior in older rats in comparison to adult rats. In addition, we wanted to determine the effects of alterations in neurochemicals (such as corticosterone, oxytocin, vasopressin, and their receptor levels) and emotional situations on this behavior. In our study, we initially completed empathy-like behavior tests and emotional tests (open field, elevated plus maze) and performed neurochemical examinations in the serum and brain tissues. In the second step of research, we applied a midazolam (benzodiazepine) treatment to examine the effect of anxiety on empathy-like behavior. In the old rats, we observed that empathy-like behavior deteriorated, and anxiety signs were more pronounced. We detected a positive correlation between the latency in empathy-like behavior and corticosterone levels and v1b receptor levels. The midazolam effect on empathy-like behavior was attenuated by flumazenil (a benzodiazepine receptor antagonist). The recordings of ultrasonic vocalization showed frequencies around 50 kHz emitted by the observer and this was associated with the expectation of social contact. Our results state that compared to adult rats, old rats were more concerned and failed during empathy-like behavior. Midazolam may improve this behavior by anxiolysis.

Nano-sized magnetic Ni particles based dispersive solid-phase extraction of trace Cd before the determination by flame atomic absorption spectrometry with slotted quartz tube: a new, accurate, and sensitive quantification method.

In this study, a new analytical strategy was developed to determine trace cadmium in aqueous samples with high sensitivity and accuracy. A combination of magnetic nickel nanoparticles (Ni-MNPs) based dispersive solid-phase extraction (DSPE) and flame atomic absorption spectrometry fitted with a slotted quartz tube (SQT-FAAS) lowered the detection limit of cadmium. The magnetic Ni nanoparticles were synthesized, characterized, and thoroughly optimized in a stepwise approach. The quartz tube was custom cut in the laboratory to suit the specifics of the flame burner. Using the optimized conditions, a limit of detection value of 0.58 µg/L and limit of quantification value of 1.93 µg/L were obtained. To demonstrate accuracy and applicability of the developed method, well water samples were analyzed for their Cd content, and matrix effect on the extraction yield was investigated. The percent recovery results calculated ranged from 93.8 to 108.2%, with corresponding standard deviation values ranging from 1.7 to 7.7. These results established the developed method as sensitive, accurate, and precise for determination of cadmium at trace levels.

Oleic and stearic acid-coated magnetite nanoparticles for sonication-assisted binary micro-solid phase extraction of endocrine disrupting compounds, and their quantification by GC-MS.

Nanosized magnetic nanoparticles (MNPs) were utilized for the preconcentration of 12 analytes including pesticides, alkylphenols, hormones and bisphenol A prior to their determination by GC-MS. The extraction efficiency of the MNPs was enhanced by coating them with oleic acid and stearic acid. A binary system consisting of the two kinds of coated MNPs was optimized using a multivariate experimental design which evaluated main experimental variables and their interactions. Under optimized conditions, the following figures of merit are found: (a) Enrichment factors ranging from 64 to 345; (b) detection limits between 0.13 and 2.7 µg L-1; and (c) recoveries from spiked underground well water and municipal wastewater between 90 and 109%. The closeness of the results to 100% validated the method and underpinned its trueness for quantitative determinations. Graphical abstract Schematic representation of sonication-assisted binary micro-solid phase extraction based on oleic acid coated (OAc-) and stearic acid coated (SAc-) magnetite nanoparticles (MNPs) for the determination of endocrine disrupting compounds by GC-MS (TIC: total ion chromatogram).

Accurate and sensitive determination of lead in black tea samples using cobalt magnetic particles based dispersive solid-phase microextraction prior to slotted quartz tube-flame atomic absorption spectrometry.

Newly developed combination of magnetic cobalt particles based dispersive solid-phase microextraction (Co-MP-DSPME) and slotted quartz tube attached flame atomic absorption spectrometry (SQT-FAAS) was utilized to determine lead at trace levels in tea samples. Co-MPs' adsorbent properties were tested and validated for their selectiveness to lead. Only with a few and short extraction steps (i.e. adding MPs, mixing, decanting and eluting) analyte was extracted from sample solution rapidly and efficiently. Limit of detection (LOD) and limit of quantification (LOQ) for the developed method (Co-MP-DSPME-SQT-FAAS) were found to be 7.77 µg/L and 25.9 µg/L, respectively. Matrix matching strategy was performed and outcomes indicated that the developed method is applicable with the high percent recovery values of 110.1 ±â€¯4.5 and %102.9 ±â€¯4.2 for 100 and 300 µg/kg lead standard spiked black tea samples, respectively. The method was also applied to standard reference material to check the accuracy of the method.

A new combination for the determination of ultratrace cadmium: solid-phase microextraction by stearic acid-coated magnetic nanoparticles prior to batch-type hydride generation atomic absorption spectrometry.

Solid-phase microextraction method based on stearic acid-coated magnetic nanoparticle has been combined with batch-type hydride generation atomic absorption spectrometry (BT-HGAAS) system to determine cadmium at ultratrace levels. After the adsorption of cadmium ions onto stearic acid-coated magnetic nanoparticles, they were easily separated from the aqueous phase by means of a magnet. All the instrumental and experimental parameters such as pH of buffer solution, interaction period, concentration, and volume of NaBH4 were optimized. Under the optimal conditions, limit of quantification (LOQ) and limit of detection (LOD) for the solid-phase microextraction (SPME) based on stearic acid-coated magnetic nanoparticles-BT-HGAAS (SACMNP-BT-HGAAS) method were obtained as 270.8 ng/L and 81.7 ng/L, respectively. The matrix-matching calibration method was performed in order to improve the accuracy of cadmium quantification in tap water and the recovery results obtained were as follows: 88.56 ± 8.92 and 97.43 ± 9.76, for 6.0 and 8.0 ng/mL of cadmium-spiked tap water samples, respectively. Graphical abstract ᅟ.

Sensitive determination of cadmium using solidified floating organic drop microextraction-slotted quartz tube-flame atomic absorption spectroscopy.

In this study, solidified floating organic drop microextraction (SFODME) by 1-undecanol was combined with slotted quartz tube flame atomic absorption spectrometry (SQT-FAAS) for the determination of cadmium at trace levels. Formation of a complex with 4,4'-dimethyl-2,2'-bipyridine facilitated the extraction of cadmium from aqueous solutions. Several chemical variables were optimized in order to obtain high extraction outputs. Parameters such as concentration of the ligand, pH, and amount of buffer solution were optimized to enhance the formation of cadmium complex. The SFODME method was assisted by dispersion of extractor solvent into aqueous solutions using 2-propanol. Under the optimum extraction and instrumental conditions, the limit of detection and limit of quantitation values obtained for cadmium using the combined methods (SFODME-SQT-FAAS) were found to be 0.4 and 1.3 µg L-1, respectively. Matrix effects on the method were also examined for tap water and wastewater, and spiked recovery results were found to be very satisfactory. Graphical Abstract SFODME-SQT-FAAS system for sensitive determination of cadmium.