فهرست مطالب

Biological and Biomedical Journal - Volume:6 Issue: 4, Autumn 2020
  • Volume:6 Issue: 4, Autumn 2020
  • تاریخ انتشار: 1400/08/15
  • تعداد عناوین: 4
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  • Investigation of the therapeutic effect of nicotine and its metabolites on the brain
    Amin Ataie*, Ramin Ataee, Hossein Khaleghzadeh Page 1

    The effect of Cotinine, active metabolite of nicotine, on Aβ1-42 neurotoxicity was investigated. Cotinine possesses a longer plasma half-life, lower toxicity and it is a partial agonist of the nicotinic acetylcholine receptors (nAChR). Cotinine prolonged the survival of cortical neurons exposed to Aβ1-42. These results indicated that cotinine has a neuroprotective effect by inhibition of the formation of amyloid beta in the brain. The nicotine and its metabolites function in the brain are controversial. In this review, the mechanism of nicotine and the metabolites on neuronal physiology were studied, also their effects on learning and memory were investigated.Some studies indicate the pharmacological action of nicotine in the treatment of Parkinson's disease. There are three nicotine active metabolites that have pharmacological effects in some parts of the brain, such as cotinine, norcotinine, nornicotine, also cotinine, and nornicotine both had beneficial effects in learning and memory without adverse effects.

    Keywords: Cotinine, Nicotine, Alzheimer Disease, Parkinson Disease, Cognition, Neuroprotection, Nicotinic Acetyl Choline Receptor
  • Anesthesia for leg amputation in high risk patients: Case reports
    Tomoki Nishiyama* Page 2
    Background

    High risk cases of leg amputation were one of major concerns in anesthesiologists. 

    Cases:

    Sixteen cases with American Society of Anesthesiologists physical status (ASA-PS) 3 or 4 for leg amputation were reported.  Fifteen patients were medicated with more than two anticoagulants and 11 patients had bleeding tendency.  Thirteen patients received below knee amputation (BKA) and three patients received above knee amputation (AKA).  Twelve patients received sciatic and femoral nerve blocks using ropivacaine and lidocaine then intravenous fentanyl and/or midazolam, and four received general anesthesia with inhalation anesthetics.  Vasopressors were administered in 3/12 patients anesthetized by blocks and all patients by general anesthesia.  Heart rate increased to more than 120 beats/min during surgery in all cases in general anesthesia.  VAS scores in postoperative 12 hours after surgery was 0 to 3 in patients anesthetized with blocks and 4 to 7 in patients with general anesthesia.  Phantom pain might be less in blocks.  

    Conclusions

    Femoral and sciatic nerve blocks with small dose of fentanyl and/or midazolam seemed to be better than general anesthesia in terms of hemodynamics during surgery and postoperative analgesia.

    Keywords: lower leg, amputation, femoral nerve block, sciatic nerve block, general anesthesia
  • A Study on the Effect of Concurrent Administraon of Hydroalcoholic Extract of Cannabis Sava and Capsaicin on PTZ-Induced Seizure in Neonatal Rats
    Elnaz Khorasanian, Zeinab Dadgar*, Delbar Daneshjoo, Narges Abdali Page 3

    Introducon:

    Concurrent acvity of a set of neurons, due to their severity and extent, causes different seizure behaviors. More than three percent of the world's populaon has epilepsy and convenonal medicaons have undesirable side effects if taken, so access to substances with fewer side effects is essenal. The Cannabis sava is adapted to the Iranian climate and has an-seizure effects due to its factors. Capsaicin, acve constuents in red peppers by destroying the sensory nerve terminals in the sensive postnatal period has the potenal to affect brain structure and performance. This study invesgates the effects of hydroalcoholic extract of cannabis Sava and capsaicin heated flowers on PTZ-induced seizures in twenty-day-old rats alone or under neonatal administraon.

    Material and methods

    The hydroalcoholic extract of cannabis Sava was prepared by maceraon and dissolved in saline, ethanol, and twin 80. The dose of 50 mg/kg of the extract was administered to 4- to 10-day-old rats by intraperitoneal injecon. In the capsaicin-treated group, the compound with a dose of 50 mg/kg was injected intraperitoneal injecon on the second day aer birth. To assess acute seizures, PTZ was administered at a dose of 50mg/kg into a 20-day-old rat and the seizure behavior of the animals was invesgated at 60 minutes. The groups were evaluated and compared with PTZ and solvent groups in terms of two quanes, the duraon of the different stages of the seizure and the delay me to the occurrence ofseizure.

    Results

    Comparing the effects of neonatal administraon of capsaicin and the chronic effect of the extract, the results showed a significant increase in delay me to stage 4 seizure (P <0.001) and a decrease in the duraon of thisstage to zero.

    Discussion

    Degradaon of the sensory nerve terminals by capsaicin and deprivaon of somatosensory senses in the postnatal sensive developmental period lead to structural and funconal changes at different levels of the brain. Smulaon of cannabinoid receptors (CB1) in the brain affected by the extract overcomes these changes and reduces the severity of seizure aacks. Considering the presence of influencing factors on the cannabinoid system in plant extract, it can be concluded that the extract may have an-seizure effects by inhibing the glutaminergic system and smulang the GABAA system.

    Keywords: C-Type Nerve Fiber, Rat Newborn, Seizure Aack, Cannabis Extract, Capsaicin
  • The Microbiological Effects of Calcite on Dune Sands and the its Strength and Hydraulic Changes
    Ahmad Riahi* Page 4

    Microbial induced calcite precipitation (MICP) is a novel ground improvement method to increase strength and reducing the hydraulic conductivity of sand using natural biogeochemical processes. This paper aims to study the effectiveness of MICP in improving the shear strength and hydraulic conductivity of dune sand. A species of Sprosarcina group, S. urea was used to trigger the calcite precipitation. Sand specimens were treated using of bacterial cell and urea– calcium chloride solutions. Measured strength and stiffness values from unconfined compression tests ranged for treated samples were 527.7 kPa and 69.43 MPa, respectively, while strength and stiffness values of control specimen (untreated sand) in triaxial condition (confining pressure 50 kPa) were measured 255.7 kPa and 25.5 MPa, respectively. Permeability coefficient value of treated sample was reduced 50.5% to treated sample by falling head test.

    Keywords: MICP, soil improvement, shear strength, hydraulic conductivity, S. urea