PCB (Aroclor 1254) enhances oxidative damage in rat brain regions: protective role of ascorbic acid

PCBs are one of the environmental toxicants and neurotoxic compounds which induce the production of free radicals leading to oxidative stress. Oxidative stress is a contributing factor to alteration caused in neurodegenerative processes. The ability of Vitamin C to retard oxidative processes has been recognized for many years. Therefore, the present experiment was carried out to determine the antioxidant role of ascorbate on Aroclor 1254 induced oxidative stress in brain regions of albino rats. One group of rats received corn oil as vehicle for 30 days as control. The other group of rats were administered Aroclor 1254 at a dose of 2 mg/kg bw/day intraperitoneally for 30 days. One group of rats received Vitamin C (100 mg/kg bw/day) orally simultaneously with Aroclor 1254 for 30 days. The brain was dissected to cerebral cortex (Cc), cerebellum (C) and hippocampus (H). Enzymatic and non-enzymatic antioxidants such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione-S-transferase (GST), reduced glutathione (GSH) and Vitamin C were estimated. Hydrogen peroxide (H(2)O(2)), lipid peroxidation (LPO) and acetylcholine esterase activity (AchE) were determined. Activities of SOD, CAT, GPx, GST, AchE and the concentration of GSH, Vitamin C were decreased while an increase in H(2)O(2) and LPO were observed in brain regions of PCB treated animals. Vitamin C administration retrieved all the parameters except GST, significantly. These results suggest that PCB induces oxidative stress in rat brain by decreasing the activities of antioxidant enzymes, which can be protected by Vitamin C treatment.     

Impact of COVID‐19 on the mental health of surgeons and coping strategies

Unprecedented times call for extraordinary measures. While surgeons across the globe try to comprehend the evolving facade of the COVID‐19 pandemic and improvise surgical practice to the best of their ability, the psychological impact of the stress on their own mental health and well‐being has been underestimated. This paper aims to review the indirect and overt factors that may affect the mental health of a surgeon in the present circumstances. Furthermore, it will aim to highlight key coping mechanisms at an individual and institutional level, so as to mitigate the negative psychological impact on surgeons.     

Anatomy of the pituitary, thyroid, parathyroid and adrenal glands

The anatomy of four major endocrine glands (thyroid, parathyroid, pituitary and adrenal) is the subject of this chapter. Other endocrine glands (such as the hypothalamus, pineal gland, thymus, endocrine pancreas and the gonads) exist, but are beyond the scope of this chapter. A detailed understanding of anatomy is essential for several reasons: to enable accurate diagnosis and plan appropriate management; to perform surgery in a safe and effective manner avoiding damage to adjacent normal structures and; to anticipate and recognize variations in normal anatomy. In addition to gross anatomy, clinically relevant embryological and histological details of these four glands are also discussed.     

Thoracic spine morphology of a pseudo-biped animal model (kangaroo) and comparisons with human and quadruped animals

Purpose

Based on the structural anatomy, loading condition and range of motion (ROM), no quadruped animal has been shown to accurately mimic the structure and biomechanical function of the human spine. The objective of this study is to quantify the thoracic vertebrae geometry of the kangaroo, and compare with adult human, pig, sheep, and deer.

Methods

The thoracic vertebrae (T1–T12) from whole body CT scans of ten juvenile kangaroos (ages 11–14 months) were digitally reconstructed and geometric dimensions of the vertebral bodies, endplates, pedicles, spinal canal, processes, facets and intervertebral discs were recorded. Similar data available in the literature on the adult human, pig, sheep, and deer were compared to the kangaroo. A non-parametric trend analysis was performed.

Results

Thoracic vertebral dimensions of the juvenile kangaroo were found to be generally smaller than those of the adult human and quadruped animals. The most significant (p < 0.001) correlations (Rho) found between the human and kangaroo were in vertebrae and endplate dimensions (0.951 ≤ Rho ≤ 0.963), pedicles (0.851 ≤ Rho ≤ 0.951), and inter-facet heights (0.891 ≤ Rho ≤ 0.967). The deer displayed the least similar trends across vertebral levels.

Conclusions

Similarities in thoracic spine vertebral geometry, particularly of the vertebrae, pedicles and facets may render the kangaroo a more clinically relevant human surrogate for testing spinal implants. The pseudo-biped kangaroo may also be a more suitable model for the human thoracic spine for simulating spine deformities, based on previously published similarities in biomechanical loading, posture and ROM.

     

Case report and literature review of chronic neuropathic pain associated with peripheral venous cannulation

We report a case of neuropathic pain following peripheral venous cannulation for an elective surgical procedure and discuss the various mechanisms by which this could occur. The mostly likely trigger in this case is phlebitis as the onset of symptoms coincided with the local infection. Neuropathic pain can occur following innocent interventions and its impact on the patient’s quality of life may be reduced by timely recognition and management.     

Diagnosis of Hodgkin lymphoma in the modern era

The Hodgkin lymphomas are a family of unique lymphoma subtypes, in which the nature of the neoplastic cell was enigmatic for many years. Much of the mystery has been solved, with all forms now considered to be of B-cell origin, in most cases of germinal centre derivation. Today we recognize Hodgkin lymphoma as an eponym that encompasses multiple entities. One of the unifying themes is the major contribution from the tumour microenvironment. Both the character of the neoplastic cells and the nature of the immune environment are critical to accurate diagnosis. Moreover, an understanding of the molecular alterations that characterize both the neoplastic cells and their microenvironment have led to therapeutic advances, targeting both neoplastic and reactive components. Other conditions may foster a similar inflammatory milieu and lead to lymphoproliferations that mimic the Hodgkin lymphomas. In this review we provide an update on the diagnostic features of the various subtypes and include additional information relevant for prognostic evaluation and investigation of potential therapeutic targets. Additionally, we also discuss those conditions that often cause confusion in diagnosis and need to be distinguished from the Hodgkin lymphomas.