Publications by authors named "Raj D Mehra"

Background: Exposure to arsenic has been reported to affect the nervous system in a number of ways. Various epidemiological studies suggest cognitive impairment in subjects following exposure to environmental arsenic. The goal of the present study was to determine if supplementation of exogenous α-lipoic acid (ALA) could ameliorate sodium arsenite (NaAsO) induced adverse effects on learning and memory and synaptic connectivity in rat hippocampus.

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Article Synopsis
  • - The study focuses on analyzing the Hypoglossal Canal (HC), a bony passage that carries the hypoglossal nerve and blood vessels, examining its shape and relationships with the Occipital Condyle (OC) using 50 human dry skulls.
  • - Researchers found notable variations in the HC among the skulls, with 52% exhibiting unique features like spurs and incomplete septa, particularly more on the left side, but no complete septa were observed.
  • - The findings aim to enhance understanding of HC morphology in the North Indian population, which could improve surgical procedures and outcomes related to this area of the skull.
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Background: The transcondylar approach (TCA) has gained importance in recent era which enables shorter and direct route to access the lesions ventral to the brainstem. The important step in this approach is resection of the occipital condyle (OC). The detailed knowledge of bony anatomy of OC and its relation to the hypoglossal canal (HC), condylar canal (CC), and jugular foramen (JF) is very important to avoid any iatrogenic injury during craniovertebral surgeries.

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The present study focused on the role of exogenous alpha lipoic acid (ALA) in amelioration of inorganic arsenic () induced effects on apoptosis and apoptosis associated proteins in developing rat hippocampus. NaAsO (1.5/2.

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The effects of arsenic exposure during rapid brain growth period (RBGP) (postnatal period 4-11) on pyramidal neurons of cornu ammonis (specifically CA1 and CA3 regions) and granule cells of dentate gyrus (DG) of rat hippocampus were studied. Wistar rat pups, subdivided into the control (group I) and the experimental groups (group II, III, and IV), received distilled water and sodium arsenite (aqueous solution of 1.0, 1.

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The effects of sodium arsenite exposure on the hepatic maturation period of cellular and functional reorganization in developing rat livers were evaluated. Animals received intraperitoneal injections of sodium arsenite (1.5 mg/kg body weight) or distilled water on days 9 to 28 after birth.

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Objective: The present study was undertaken to investigate the effects of early postnatal exposure to sodium arsenite (NaAsO(2)) on rat testis.

Materials And Methods: Wistar rat pups were administered aqueous solution of NaAsO(2,) 1.5 mg/kg body weight (bw) (experimental) and distilled water (control), respectively, by intraperitoneal route (i.

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Ageing of the brain is accompanied by variable degrees of cognitive decline. Estrogens have profound effects on brain ageing by exerting neurotrophic and neuroprotective types of action. Furthermore, exercise has also been claimed to play a role in the non-pharmacological prevention of psycho-neuronal decline with ageing.

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The present work focussed on the effect of exogenous α-lipoic acid (ALA) administration on retention memory and oxidative stress markers in the hippocampus subsequent to early post-natal exposure of rat pups to sodium arsenite (NaAsO(2)). Wistar rat pups were divided into the control groups receiving either no treatment (Ia) or distilled water by intraperitoneal route (i.p.

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Although much is known about the protective effect of acute estrogen therapy in cerebral ischemia, relatively little is known about its effect on functional outcome at different ages. The impact of age is, however, important on the efficacy of steroids in the central nervous system. We investigated whether a single dose of estradiol pre-treatment would be neuroprotective in young (4 months), middle-aged (9 months) and old (18 months) female gerbils following 10min global brain ischemia.

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In present study, hydroalcoholic extract of C. mukul significantly improved the cardiac function and prevented myocardial ischemic impairment manifested in the form of increased heart rate, decreased arterial pressure, increased left ventricular end diastolic pressure, and altered myocardial contractility indices. C.

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Recently we reported that chronic treatment with 17beta-estradiol (E2) or tamoxifen (TAM) regulates the ovariectomy-induced downregulation of the key molecules linked to hippocampal synaptic plasticity and signal transduction pathway. We now report modulation of the antiapoptotic (Bcl-2) and proapoptotic (Bax) proteins in the hippocampus of both the ovariectomized (OVX) rats as well as those given E2 or TAM subcutaneously as a daily dose for four weeks post-ovariectomy. Forty bilaterally OVX animals were divided into four groups of 10 each, namely i) OVX+E2 (0.

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The effects of arsenic exposure during rapid brain growth (RBG) period were studied in rat brains with emphasis on the Purkinje cells of the cerebellum. The RBG period in rats extends from postnatal day 4 (PND 4) to postnatal day 10 (PND 10) and is reported to be highly vulnerable to environmental insults. Mother reared Wistar rat pups were administered intraperitoneal injections (i.

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We report here the in vivo effects of estrogen (E2) on modulation of synaptic plasticity and the agonistic (estrogen-like) role of selective estrogen receptor modulator (SERM), tamoxifen (TAM) in the CA1 of the rat hippocampus. Effects on synaptophysin (SYP), a presynaptic vesicular protein, and phosphorylated cyclic AMP responsive element-binding (p-CREB) protein, a signal transduction pathway molecule, were studied using the ovariectomized (OVX) experimental rat model. Bilateral ovariectomy was performed on 40 rats and these were divided into 4 groups based on the treatment they received (at 2 weeks post-ovariectomy, a subcutaneous injection daily for 4 weeks) viz.

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We have studied the distribution pattern and levels of expression of two estrogen receptor (ER) subtypes, ERalpha and ERbeta, in the normal adult (n = 10) and the aged (n = 10) female rat hippocampus with the objective to establish baseline data and the changes that occur during aging. Techniques including immunohistochemical localization, co-localization with double immunofluorescence and confocal microscopy, image analysis including neuronal counts/mm(2) area and measurements of optical density (OD) of immunoreactivity in immunoreactive neurons and Western blot analysis have been used. The results revealed ERalpha and ERbeta positive neurons in all subfields of the hippocampus with maximum presence in the stratum pyramidale of CA3.

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