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101.
Objectives: The present study was designed to evaluate the efficacy of Lactuca sativa (LS) Linn. (Asteraceae) against scopolamine-induced amnesia and to validate its traditional claim as memory enhancer.Methods: Ethanol extract of fresh LS leaves (LSEE), standardized on the basis of quercetin content, was successively partitioned using various solvents viz., hexane, ethyl acetate, and n-butanol in increasing order of polarity. LSEE (50, 100, and 200?mg/kg) and its various fractions (at a dose equivalent to dose of LSEE exhibiting maximum activity), administered orally for 14 days, were evaluated for their memory enhancing effect against scopolamine-induced (1?mg/kg, i.p.) amnesia in 3–4 months old male Laca mice (n?=?6 in each group). The memory enhancing effect was evaluated using behavioural (elevated plus maze, novel object recognition and Morris water maze tests) and biochemical parameters (acetylcholinesterase activity, malonaldehyde, superoxide dismutase, nitrite, catalase, and reduced gultathione content). The results of the test substances were compared with both scopolamine and donepezil that was used as a standard memory enhancer and acetylcholinesterase inhibitor.Results: Scopolamine elicit marked deterioration of memory and alteration in biochemical parameters in comparison to the control group. LSEE and its n-butanol and aqueous fractions significantly (P?0.05) attenuated the scopolamine-induced amnesia that was evident in all the behavioural and biochemical test parameters. LSEE (200?mg/kg) and n-butanol fraction (15?mg/kg) exhibited maximum anti-amnesic effect among various tested dose levels.Discussion: The results exhibited that LS prophylaxis attenuated scopolamine-induced memory impairment through its acetylcholinesterase inhibitory and antioxidant activity validating its traditional claim. 相似文献
102.
103.
G Patil MI Khan DK Patel S Sultana R Prasad I Ahmad 《Environmental toxicology and pharmacology》2012,34(2):436-445
Dolomite is a natural mineral of great industrial importance and used worldwide, thus millions of workers are at risk of occupational exposure. Its toxicity is however, meagerly documented. In the present investigation, a dolomite powder obtained from its milling unit was analyzed by some standard methods namely, optical microscopy, transmission electron microscopy and dynamic light scattering. Results showed that dolomite powder contained particles of different shapes and size both microparticles (MPs) and nanoparticles (NPs), suggesting potential occupational exposure of these particles. An attempt was therefore, made to investigate dolomite toxicity in a particle size-dependent manner in human lung epithelial cells A(549). The comparative toxicity evaluation of MPs and NPs was carried out by assessing their effects on cell viability, membrane damage, glutathione, reactive oxygen species (ROS), lipid peroxidation (LPO), micronucleus (MN) and proinflammatory cytokines, namely tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6). These markers of cytotoxicity, genotoxicity and inflammation were assayed in cells exposed to MPs and NPs in a dose-and time-dependent manner. Invariably, their toxic effects were dose-and time-dependent while NPs in general were significantly more toxic. Notably, NPs caused oxidative stress, genotoxicity and inflammatory responses, as seen by significant induction of ROS, LPO, MN, TNF-α, IL-1β and IL-6. Thus, the study tends to suggest that separate health safety standards would be required for micrometer and nanometer scale particles of dolomite. 相似文献
104.
Endoscopic ultrasonography is not required for staging malignant esophageal strictures that preclude the passage of a diagnostic gastroscope
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105.
Muhammad U. Ghori Liam M. Grover Kofi Asare-Addo Alan M. Smith 《Pharmaceutical development and technology》2018,23(2):183-197
Swelling, erosion, deformation, and consolidation properties can affect the performance of cellulose ethers, the most commonly used matrix former in hydrophilic sustained tablet formulations. The present study was designed to comparatively evaluate the swelling, erosion, compression, compaction, and relaxation properties of the cellulose ethers in a comprehensive study using standardised conditions. The interrelationship between various compressional models and the inherent deformation and consolidation properties of the polymers on the derived swelling and erosion parameters are consolidated. The impact of swelling (Kw) on erosion rates (KE) and the inter-relationship between Heckel and Kawakita plasticity constants was also investigated. It is evident from the findings that the increases in both substitution and polymer chain length led to higher Kw, but a lower KE; this was also true for all particle size fractions regardless of polymer grade. Smaller particle size and high substitution levels tend to increase the relative density of the matrix but reduce porosity, yield pressure (Py), Kawakita plasticity parameter (b?1) and elastic relaxation. Both KW versus KE (R2?=?0.949–0.980) and Py versus. b?1 correlations (R2?=?0.820–0.934) were reasonably linear with regards to increasing hydroxypropyl substitution and molecular size. Hence, it can be concluded that the combined knowledge of swelling and erosion kinetics in tandem with the in- and out-of-die compression findings can be used to select a specific polymer grade and further to develop and optimize formulations for oral controlled drug delivery applications. 相似文献
106.
107.
Nur Aziah Hanapi Ahmad Saifuddin Mohamad Arshad Jafri Malin Abdullah Tengku Sifzizul Tengku Muhammad Siti R. Yusof 《Journal of pharmaceutical sciences》2021,110(2):698-706
Neurotherapeutic potentials of Centella asiatica and its reputation to boost memory, prevent cognitive deficits and improve brain functions are widely acknowledged. The plant's bioactive compounds, i.e. asiaticoside, madecassoside and asiatic acid were reported to have central nervous system (CNS) actions, particularly in protecting the brain against neurodegenerative disorders. Hence, it is important for these compounds to cross the blood-brain barrier (BBB) to be clinically effective therapeutics. This study aimed to explore the capability of asiaticoside, madecassoside and asiatic acid to cross the BBB using in vitro BBB model from primary porcine brain endothelial cells (PBECs). Our findings showed that asiaticoside, madecassoside and asiatic acid are highly BBB permeable with apparent permeability (Papp) of 70.61 ± 6.60, 53.31 ± 12.55 and 50.94 ± 10.91 × 10?6 cm/s respectively. No evidence of cytotoxicity and tight junction disruption of the PBECs were observed in the presence of these compounds. Asiatic acid showed cytoprotective effect towards the PBECs against oxidative stress. This study reported for the first time that Centella asiatica compounds demonstrated high capability to cross the BBB, comparable to central nervous system drugs, and therefore warrant further development as therapeutics for the treatment of neurodegenerative diseases. 相似文献
108.
Weiwei Yan Muhammad Hassan Saleem Patrick McDonough Sean P. McDonough Thomas J. Divers Yung-Fu Chang 《Clinical and Vaccine Immunology : CVI》2013,20(8):1143-1149
Leptospira immunoglobulin (Ig)-like (Lig) proteins are a novel family of surface-associated proteins in which the N-terminal 630 amino acids are conserved. In this study, we truncated the LigA conserved region into 7 fragments comprising the 1st to 3rd (LigACon1-3), 4th to 7.5th (LigACon4-7.5), 4th (LigACon4), 4.5th to 5.5th (LigACon4.5–5.5), 5.5th to 6.5th (LigACon5.5–6.5), 4th to 5th (LigACon4-5), and 6th to 7.5th (LigACon6-7.5) repeat domains. All 7 recombinant Lig proteins were screened using a slot-shaped dot blot assay for the diagnosis of equine leptospirosis. Our results showed that LigACon4-7.5 is the best candidate diagnostic antigen in a slot-shaped dot blot assay. LigACon4-7.5 was further evaluated as an indirect enzyme-linked immunosorbent assay (ELISA) antigen for the detection of Leptospira antibodies in equine sera. This assay was evaluated with equine sera (n = 60) that were microscopic agglutination test (MAT) negative and sera (n = 220) that were MAT positive to the 5 serovars that most commonly cause equine leptospirosis. The indirect ELISA results showed that at a single serum dilution of 1:250, the sensitivity and specificity of ELISA were 80.0% and 87.2%, respectively, compared to those of MAT. In conclusion, an indirect ELISA was developed utilizing a recombinant LigA fragment comprising the 4th to 7.5th repeat domain (LigACon4-7.5) as a diagnostic antigen for equine leptospirosis. This ELISA was found to be sensitive and specific, and it yielded results that concurred with those of the standard MAT. 相似文献
109.
Hafiz Muhammad Shoaib Ambreen Gul Muazzam Asif Mir Suk-Yul Jung Abdul Matin 《Parasitology research》2013,112(3):1179-1188
Acanthamoeba is an opportunistic protozoan pathogen and known to be one of the most ubiquitous organisms, play a vital role in ecosystem, and recognized to cause blinding keratitis and rare but fatal granulomatous encephalitis involving the central nervous system with a very poor prognosis. This is due to limited availability of effective anti-Acanthamoeba drugs. The objective of the present study was to determine the efficacy of methanolic plants crude extracts on the viability and biological properties of Acanthamoeba castellanii (T4 genotype) and its cytotoxic effects on human corneal epithelial cells (HCEC). Using HCEC, it was observed that Acanthamoeba exhibited binding (>90 %) and cytotoxicity (>80 %) to host cells. However, plant crude extracts remarkably inhibited more than 70 and 60 % of Acanthamoeba binding and cytotoxicity to HCEC, respectively. It was further established that crude extracts (ranging from 0.1 to 1.5 mg/ml) exhibited amoebicidal effects, i.e., >50 % of trophozoites were killed/reduced at maximum dose (1.5 mg/ml) within 1 h incubation. However, the residual subpopulation remained static over longer incubations. Furthermore, growth assay demonstrated crude extracts inhibited >50 % Acanthamoeba numbers up to 7 days. Our results confirmed that plant crude extracts has inhibitory effects on Acanthamoeba growth and viability. Overall, these findings revealed that tested plant extracts is inhibitory to Acanthamoeba properties associated with pathogenesis. To the best of our knowledge, our findings demonstrated for the first time that selected methanol plant crude extracts exhibits inhibitory effects on biological properties of Acanthamoeba without any toxic effects on HCEC cells in vitro. 相似文献
110.
Ashley Woolbert Emily R. Calasanz Muhammad Nazim 《International journal of surgery case reports》2013,4(12):1061-1063
INTRODUCTIONLumbar herniation is uncommon, with traumatic etiology being rare. Traumatic lumbar hernias are usually caused by seatbelt injury in motor vehicle accidents. It is exceedingly uncommon to see lumbar hernias in an unrestrained passenger of a motor vehicle accident.PRESENTATION OF CASEWe present a case of a traumatic inferior lumbar hernia in a young woman who was an unrestrained driver of a vehicle involved in a high-speed collision, with multiple rollover and ejection. CT scans of the abdomen and pelvis suggested soft tissue injury involving muscles in the left lower posterior flank with traumatic herniation of the colon and small bowel. Emergent midline abdominal laparotomy confirmed herniation in the left lower quadrant. After abdominal closure, in the prone position, an extensive laceration over the left flank also confirmed herniation. Due to its dirty nature, the wound was irrigated, lavaged and covered with wound vacuum-assisted closure placement. The decision was made in favor of delayed elective hernia repair.DISCUSSIONLumbar hernias are usually caused by sudden force to the abdomen, leading to increased intra-abdominal pressure. This pressure combined with areas of weakness in the superior and/or inferior triangle lead to herniation. Uncommonly, the contents of lumbar hernias can strangulate or incarcerate leading to bowel obstruction. This can often be prevented by detection with CT and laparotomy.CONCLUSIONLumbar herniation of traumatic etiology is rare. Early detection with CT and/or exploratory laparotomy is important to avoid increases in size of the defect and bowel strangulation and incarceration. 相似文献