Inhibition of secretary PLA2 – VRV-PL-VIIIa of Russell‘s viper venom by standard aqueous stem bark extract of Mangifera indica L

The aqueous extract of Mangifera indica is known to possess anti-snake venom activities. However, its inhibitory potency and mechanism of action on multi-toxic phospholipases A2s, which are the most toxic and lethal component of snake venom is still unknown. Therefore, this study was carried out to evaluate the modulatory effect of standard aqueous bark extract of M. indica on VRV-PL-VIIIa of Indian Russells viper venom. Mangifera indica extract dose dependently inhibited the GIIB sPLA2 (VRV-PL-VIIIa) activity with an IC50 value of 6.8±0.3 μg/ml. M. indica extract effectively inhibited the indirect hemolytic activity up to 96% at ~40 μg/ml concentration. Further, M. indica extract at different concentrations (0-50 μg/ml) inhibited the edema formed in a dose dependent manner. It was found that there was no relieve of inhibitory effect of the extract when examined as a function of increased substrate and calcium concentration. The inhibition was irreversible as evident from binding studies. The in vitro inhibition is well correlated with in situ and in vivo edema inducing activities. As the inhibition is independent of substrate, calcium concentration and was irreversible, it can be concluded that M. indica extracts mode of inhibition could be due to direct interaction of components present in the extract with PLA2 enzyme. In conclusion, the aqueous extract of M. indica effectively inhibits svPLA2 (Snake venom phospholipase A2) enzymatic and its associated toxic activities, which substantiate its anti-snake venom properties. Further in-depth studies are interesting to known on the role and mechanism of the principal inhibitory constituents present in the extract, so as to develop them into potent anti-snake venom and as an anti-inflammatory agent.

A Rare Unilateral Variation in the Course of External and Internal Carotid Arteries

Vascular variations in the neck region are not uncommon. Knowledge of incidence of morphological variations in the course and branching of the carotid arteries is important for radiological interpretation and surgical correction when they are symptomatic. Internal carotid artery (ICA) is known to show elongation in its extra cranial course. Previous studies have demonstrated the incidence and clinical symptoms of this morphological entity. However, the occurrence of elongation and looping of the external carotid artery (ECA) is seldom reported in the literature. During regular dissections, we came across a rare case of unilateral morphological variation of both ECA and ICA, in a male cadaver aged about 55 years. ICA presented a curved course with convexity directed posteriorly, at the level of the C2-C3 vertebrae. ECA presented a pronounced kinking or coiling, one inch below the level of the angle of the mandible. In addition, a linguo-facial trunk arising from the ECA also presented a pronounced kinking throughout its entire length.

Variant Origin of the Left Vertebral Artery from a Vertebro-Subclavian Trunk Associated with an Unusual Branch Arising from the Brachiocephalic Trunk

Variant origin of the left vertebral artery (LVA) from the arch of aorta is well documented in the literature. Involvement of complex sequential developmental steps in the aortic arch formation results in different patterns of origin of LVA. Morphological variations in the LVA are thought to alter the cerebral hemodynamics and can cause the cerebral dysfunction. Knowledge of the morphological variations of the LVA is useful while performing the head and neck and thoracic surgeries. We here report one of the extremely rare patterns of the LVA origin, in a male cadaver aged about 65 years. LVA and left subclavian artery (LSA) arose as a common vertebro-subclavian trunk from the convexity of the aortic arch. Further, brachiocephalic trunk (BT) gave an unusual artery from its anterior surface. This artery divided into thymic and tracheal branches. Variant origin of thymic branch may be crucial during imaging and thymectomy procedures.

Neuropsychological Correlates for Obsessive Slowness.

Aim : To assess the cognitive functioning of a group of patients with OCD and a group of matched normal controls. Method : Patients of OCD were screened for selection criteria. They were assessed on Wisconson Card Sorting Test (WCST) and Continuous Performance Test (CPT) for neuro-cognitive impairments and compared the same with matched controls. Conclusions : On WCST, clinical group performed poorly, which is statistically significant. On CPT, the patient groups made significantly more wrong responses, more missed responses and took more time to respond, which is statistically significant.