Neuroanatomical MRI study: reference values for the measurements of brainstem,cerebellar vermis,and peduncles

Objectives:To set age-specific normal reference values for brainstem, cerebellar vermis, and peduncles measurements and characterize values’ variations according to gender, age, and age by gender interaction.Methods:565 normal brain magnetic resonance examinations with normal anatomy and signal intensity of the supra- and infratentorial structures were categorized into six age groups (infant, child, adolescent, young adult, middle-age adult, and old aged adults). Patients with congenital malformations, gross pathology of the supra- or infratentorial brain, brain volume loss, developmental delay, metabolic disorders, and neuropsychological disorders (n = 2.839) were excluded. On midsagittal T₁ weighted and axial T₂ weighted images specific linear diameters and ratios of the brainstem, cerebellar vermis, and peduncles were attained. Two observers assessed a random sample of 100 subjects to evaluate the inter- and intraobserver reproducibility. Intraclass correlation coefficients, means ± standard deviation, one and two-way analysis of variance tests were used in the statistical analysis.Results:Good to excellent inter- and intraobserver measurements’ reproducibility were observed, except for the transverse diameter of the midbrain, the anteroposterior diameter of the medulla oblongata at the pontomedullary and cervicomedullary junctions, cerebellar vermis anteroposterior diameter, and thickness of the superior cerebellar peduncle. Age-specific mean values of the investigated measurements were established. A significant gender-related variation was recorded in the anteroposterior diameter of the basis pontis (p = 0.044), the anteroposterior diameter of the medulla oblongata at the cervicomedullary junction (p = 0.044), and cerebellar vermis height (p = 0.018). A significant age-related change was detected in all measurements except the tectal ratio. Age by gender interaction had a statistically significant effect on the tectal ratio, inferior, and middle cerebellar peduncles’ thickness (p = 0.001, 0.022, and 0.028, respectively).Conclusion:This study provides age-specific normal mean values for various linear dimensions and ratios of the posterior fossa structures with documentation of measurements’ variability according to gender, age, and their interaction.Advances in knowledge:It provides a valuable reference in the clinical practice for easier differentiation between physiological and pathological conditions of the posterior fossa structures especially various neurodegenerative diseases and congenital anomalies.     

Situating language in a minimal social context: how seeing a picture of the speaker’s face affects language comprehension

Natural use of language involves at least two individuals. Some studies have focused on the interaction between senders in communicative situations and how the knowledge about the speaker can bias language comprehension. However, the mere effect of a face as a social context on language processing remains unknown. In the present study, we used event-related potentials to investigate the semantic and morphosyntactic processing of speech in the presence of a photographic portrait of the speaker. In Experiment 1, we show that the N400, a component related to semantic comprehension, increased its amplitude when processed within this minimal social context compared to a scrambled face control condition. Hence, the semantic neural processing of speech is sensitive to the concomitant perception of a picture of the speaker’s face, even if irrelevant to the content of the sentences. Moreover, a late posterior negativity effect was found to the presentation of the speaker’s face compared to control stimuli. In contrast, in Experiment 2, we found that morphosyntactic processing, as reflected in left anterior negativity and P600 effects, is not notably affected by the presence of the speaker’s portrait. Overall, the present findings suggest that the mere presence of the speaker’s image seems to trigger a minimal communicative context, increasing processing resources for language comprehension at the semantic level.     

Mucilage-capped silver nanoparticles for glucose electrochemical sensing and fuel cell applications

A simple, cost-effective and green mucilage-capped silver nanoparticles (Mucilage-AgNPs) modified glassy carbon electrode (GC) composite was constructed for efficient and facile electrochemical oxidation of glucose for the first time. Mucilage-AgNPs were synthesized through the direct chemical reduction of Ag⁺ by mucilage extracted from Opuntia ficus-indica. Mucilage-AgNPs were identified and characterized using ultraviolet-visible spectroscopy, transmission electron microscopy and square wave voltammetry. Modification of the GC with AgNPs was carried out via a transfer-sticking technique with an immobilization time of 1 h. The Mucilage-AgNPs/GC composite was studied as a possible anode for glucose oxidation in a biofuel cell. The composite resulted in glucose oxidation with a current density and power density of 85.7 μA cm⁻² and 25.7 μW cm⁻², respectively. Glucose sensing using the Mucilage-AgNPs/GC composite was achieved successfully via two pathways: glucose oxidation and AgNP inhibition. The glucose oxidation-based sensor showed a lower detection limit of 0.01 mM and a linear range of 0.01 to 2.2 mM. The AgNPs inhibition-based sensor provides an indirect determination pathway of glucose with a detection limit of 0.1 mM and a linear range of 0.1 to 1.9 mM. AgNP inhibition is a novel pathway that could be used for determining a large number of organic and inorganic molecules. Overall, the Mucilage-AgNPs/GC is considered a pioneering composite for glucose sensing and fuel cell applications.

A simple, cost-effective and green mucilage-capped silver nanoparticles (Mucilage-AgNPs) modified glassy carbon electrode (GC) composite was constructed for efficient and facile electrochemical oxidation of glucose for the first time.     

Ginseng aqueous extract ameliorates lambda‐cyhalothrin‐acetamiprid insecticide mixture for hepatorenal toxicity in rats: Role of oxidative stress‐mediated proinflammatory and proapoptotic protein expressions

This study was carried out to evaluate the protective effects of Panax ginseng aqueous extract (GAE) against hepatorenal toxicity induced by lambda‐cyhalothrin‐acetamiprid insecticide mixture in rats. A total of 32 male albino rats were assigned into four groups. Normal control group received distilled water. Insecticide control group intoxicated with the insecticide at a dose of 2.14 mg/kg b.wt orally day after day for 45 days. GAE control group was treated with GAE at a dose 200 mg/kg b.wt orally. GAE experimental group was administered GAE 1 hour before insecticide administration. Intoxication of rats with the insecticide caused a significant increase in serum aspartate aminotransferase and alanine aminotransferase activities and urea and creatinine levels as well as malondialdehyde concentration and proteins expression of caspase‐3 and induced nitric oxide synthase in hepatic and renal tissues. However, it decreased the serum levels of total protein and globulin and reduced the glutathione content and catalase activity in hepatic and renal tissues. In addition, insecticide induced histopathological alterations in both hepatic and renal tissues. In contrast, GAE modulated insecticide‐induced alterations in liver and kidney functions and structures as it ameliorated the effects of insecticide on the above mentioned parameters. These results indicated that GAE was a potent antioxidant agent that could protect rats against insecticide‐induced hepatorenal toxicity.     

Molecular signalling of a novel curcumin derivative versus Tadalafil in erectile dysfunction

The efficacy of a novel curcumin derivative (NCD) versus tadalafil in erectile signalling was assessed. Ten control male rats and 50 diabetic male rats were used and divided into the following: diabetic (DM), curcumin (CURC), NCD, tadalafil and NCD combined with tadalafil rat groups. Cavernous tissue gene expression of heme oxygenase‐1 (HO‐1), Nrf2, NF‐B and p38, enzyme activities of heme oxygenase (HO) and nitric oxide synthase (NOS), cGMP and intracavernosal pressure (ICP)/mean arterial pressure (MAP) were assessed. Results showed that 12 weeks after induction of diabetes, erectile dysfunction (ED) was confirmed by the significant decrease in ICP/MAP, a significant decrease in cGMP, NOS, HO enzyme activities, a significant decrease in HO‐1 gene and a significant increase in NF‐?β, p38 genes. Administration of all therapeutic interventions led to a significant increase in ICP/MAP, cGMP levels, a significant increase in HO‐1 and NOS enzymes, a significant increase in HO‐1, and Nrf2 gene expression, and a significant decrease in NF‐?β, p38 gene expression. NCD or its combination with tadalafil showed significant superiority and more prolonged duration of action. In conclusion, a tendency was observed that CURC and NCD have high efficacy and more prolonged duration of action in enhancing erectile function.     

An association between ethanol-evoked enhancement of c-jun gene expression in the nucleus tractus solitarius and the attenuation of baroreflexes

BACKGROUND: An increased expression of Fos, the protein product of the immediate early gene c-fos, in the nucleus tractus solitarius (NTS) is associated with dysfunction in baroreceptor reflex control of heart rate. Our previous studies demonstrated that ethanol attenuates baroreflex sensitivity (BRS) in rats and humans. In this study, we tested the hypothesis that enhanced expression of the immediate early gene c-jun (an index of neuronal activity) in the NTS contributes to the baroreflex dysfunction caused by ethanol. METHODS: Conscious male spontaneously hypertensive (SHR) and Wistar-Kyoto (WKY) rats were used to measure blood pressure, heart rate, and baroreflex sensitivity (Oxford method). The c-jun messenger RNA (mRNA) expression in NTS was measured by in situ hybridization. RESULTS: Ethanol elicited dose-dependent attenuation in BRS in WKY rats, which was associated with significant increases in c-jun mRNA in the NTS. In contrast, ethanol had no effect on BRS or c-jun mRNA in the NTS of the SHRs; the latter exhibited significantly lower BRS and higher c-jun mRNA in the NTS compared with WKY rats. CONCLUSIONS: An increased basal level of c-jun mRNA in the NTS may contribute to the reduced BRS in the SHR, and ethanol enhancement of neuronal activity of the NTS, expressed as increased c-jun mRNA expression, may contribute to its attenuation of BRS, which highlights the NTS as a neuroanatomical target for ethanol action on baroreflexes.