A Novel Histological Technique to Assess Severity of Traumatic Brain Injury in Rodents: Comparisons to Neuroimaging and Neurological Outcomes

Here we evaluate an alternative protocol to histologically examine blood-brain barrier (BBB) breakdown, brain edema, and lesion volume following traumatic brain injury (TBI) in the same set of rodent brain samples. We further compare this novel histological technique to measurements determined by magnetic resonance imaging (MRI) and a neurological severity score (NSS). Sixty-six rats were randomly assigned to a sham-operated, mild TBI, moderate TBI, or severe TBI group. 48 h after TBI, NSS, MRI and histological techniques were performed to measure TBI severity outcome. Both the histological and MRI techniques were able to detect measurements of severity outcome, but histologically determined outcomes were more sensitive. The two most sensitive techniques for determining the degree of injury following TBI were NSS and histologically determined BBB breakdown. Our results demonstrate that BBB breakdown, brain edema, and lesion volume following TBI can be accurately measured by histological evaluation of the same set of brain samples.

Application of M. Heidenhain’s ferric haematoxylin for the study of semi-thin sections (human adenohypophysis)

Heidenhain´s iron hematoxylin has been one of the most useful methods of classical cytology. Its ability to stain simultaneously many cell and extracellular structures makes it a general purpose histological technique. This current work describes its application to semithin sections, using human adenohypophysis, discussing the staining mechanism and showing his usefulness to evidence cytological variability and to perform image analysis.

Biological responses in gills and hepatopancreas of Ucides cordatus (Crustacea, Decapoda, Ocypodidae) as indicative of environmental contamination in mangrove areas in Maranhão State, Brazil

This study aimed to identify alterations in gills and hepatopancreas of the crab Ucides cordatus as indicative of environmental contamination in mangrove areas subject to chemical effluents from port activities in Maranhão, Brazil. Samples of gills and hepatopancreas were removed from each animal and fixed in Davidson's solution until the procedure of histological technique. The biometric data (means and standard deviations) of the specimens collected in the study areas indicated that the crabs in the reference area are significantly (P < 0.05) higher and heavier than the crabs collected in the potentially impacted area (port area). Gill alterations (rupture of pilaster cells, dilation of the marginal channel, cuticle rupture and necrosis) and hepatopancreas alterations (abnormal lumen, vacuolized B cells, pycnotic nuclei and necrosis) were significantly (gbn < 0.05) more frequent in crabs collected in the port area than crabs collected in the reference area. These data indicate that the health of crabs is compromised due to the pollutants present in the mangroves that surround the port area in São Marcos’ Bay.

Histological assessment for the effect of Cypermethrin in the skin of local breed rabbits

Research has been designed to focusing and evaluation the effect of cypermethrin as insecticide material in the skin of the rabbits. Cypermethrin was applied on the skin after shaving the dorso-lateral aspect of rabbits .The animals (12) were classified into four groups (A, B, C and D), three animals per group. Groups (B, C and D) were exposed to cypermethrin at doses (0.001, 0.005, 0.010)mg/kg respectively, while (A) was a control group. After ten days of drug's application, animals of group (D) were died at ending of the study because they received heavy dose. The groups (B and C) shown excitation signs, followed by inhibition and depression of their activity. The animals of groups (A, B and C) were scarified and a specimens (0.5) cm3 of skin from the dorso- lateral aspect were obtained, washed with water and put in formalin (10)% then processed after (24) hours by using histological technique, sectioned at (5)µm thickness, stained with Hematoxylin and Eosin a then examined under light microscopic at different powers. http://dx.doi.org/10.25130/tjps.25.2020.022

Immunoreactivity of arcuate nucleus astrocytes in rats after intragastric administration of habanero peppers (Capsicum Chinese Jacq.)

Habanero pepper fruits contain capsaicin (CAP) characterised by a spicy taste. Astrocytes express vanilloid receptor (TRPV1), which interacts with cannabinoids including CAP. Only a few studies revealed that CAP leads to alterations of the arcuate nucleus (ARC) structures. The aim of this study was to analyse the GFAP (GFAP-IR) and S100β (S100β-IR) immunoreactive astrocytes of ARC in adult rats after intragastric administration of habanero pepper fruits. Adult, Wistar rats received a peanut oil – control group (C) – and oil suspension of habanero pepper fruits at a dose of 0.08 g dm/kg b.w. for 7 days – E1 group – and 28 days – E2 group. After euthanasia, the brains were embedded in paraffin blocks using a routine histological technique. Frontal slices of ARC were immunohistochemically stained for GFAP and S100β using specific antibodies in the peroxidase-antiperoxidase method. Astrocytes of ARC were morphologically and morphometrically analysed under a light microscope. The results of the study did not reveal statistically significant changes in the density of GFAP-IR cells in E1 and E2 groups of rats in comparison with group C. A statistically significant increase in the density of S100β-IR astrocytes was observed in the E1 group and a decrease in the E2 group. Astrocytes with expression of both studied proteins were characterised by morphological alterations in ARC in the E2 group. The obtained results suggest an influence of CAP contained in habanero pepper fruits on the reactivity of astroglia, which may have an impact on the astrocyte-neuron interactions in order to maintain a proper activity of nervous cells in ARC.