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951.
Shivayogi P Hiremath H K Shanmukha Swamy Shrishailappa M Badami Saraswati B Patil Ramesh L Londonkar 《Pharmaceutical biology》2013,51(1):48-52
The ethanol and petroleum ether (60–80°C) extracts of S. densiflora, Benth. (Scrophulariaceae), were administered orally to pregnant albino rats for 7 days at the dose of 10 and 20 mg/100 g body weight and showed significant antifertility and estrogenic activity. Histological studies of uterus were carried out to confirm the estrogenic activity of plant extracts. The antifertility activity was reversible on withdrawal of the plant extract treatment. 相似文献
952.
The application of PCR for the direct and sensitive detection of food-borne pathogens is largely affected by the quality of the template DNA prepared from food samples. In the present study, a chemical extraction method of bacterial DNA from spiked milk samples for the direct detection of Staphylococcus aureus and Yersinia enterocolitica was evaluated by PCR. Gene specific primers were designed to target the nuclease (nuc) and the attachment invasion locus (ail) genes of S. aureus and Y. enterocolitica, respectively and used in PCR. A combination of organic solvents, detergents and alkali in the DNA extraction method permitted a detection limit of 10 cfu ml(-1) milk for both the pathogens. When equal numbers of S. aureus and Y. enterocolitica were spiked in milk samples, the individual detection limit was determined to be 10(3) cfu ml(-1) milk. Simultaneous amplification of 482 and 359 bp fragments of the nuc and ail genes was obtained using the primer pairs in a single reaction. Multiplex PCR enabled the detection of 10(4) cfu ml(-1) milk of S. aureus and Y. enterocolitica without any pre-enrichment step. A combination of conventional isolation technique and PCR using DNA extracted by the proposed method was used to test raw milk samples for possible contamination with S. aureus and Y. enterocolitica. The presence of S. aureus in the tested samples was indicated by both the methods while Y. enterocolitica could not be detected in any of the samples. The template DNA extraction method developed in this study is rapid, sensitive and avoids interference from potential PCR inhibitors and demonstrates the potential of detecting multiple pathogens in milk samples without any enrichment. 相似文献
953.
Ramesh C Bansal 《Journal of the American Society of Echocardiography》2002,15(6):661-664
A case of a 73-year-old asymptomatic man with a large saphenous vein graft aneurysm first diagnosed 16 years after bypass operation is presented. The lesion was first suspected on routine transthoracic echocardiography and further clarified by transesophageal echocardiography. Selective graft angiography confirmed the diagnosis and surgical therapy included resection of the graft aneurysm and coronary artery bypass grafting. 相似文献
954.
Laxmi Manral Natrajan Muniappan Pradeep K. Gupta Kumaran Ganesan Ramesh Chandra Malhotra Rajagopalan Vijayaraghavan 《Drug and chemical toxicology》2013,36(2):108-113
The breathing pattern of mice that were exposed to fentanyl aerosol was studied (2.7, 5.7, 6.0, 10.0, and 23.6 μg/m3; for 1 hour), using dimethyl sulfoxide as a vehicle. This study was conducted in a head-only exposure assembly. Body plethysmographs connected to a volumetric pressure transducer were used to capture the respiratory signals, and an on-line computer program capable of recognizing the changes in the breathing pattern was used for monitoring the respiratory pattern. The response of mice to fentanyl exposure was found to be concentration dependent. A lower concentration (2.7 μg/m3) showed fast recovery and no mortality, while 100% mortality was observed at a higher concentration (23.6 μg/m3). No sensory, pulmonary irritation, and airway limitation in mice was observed, and death occurred probably due to respiratory depression. The concentration that decreased 50% of the respiratory frequency (RD50) was estimated to be 6.4 μg/m3. The extrapolated human threshold limit value, calculated from the RD50 value, was found to be 0.192 μg/m3. The concentration that caused 50% mortality in exposed mice (LC50) was estimated to be 8.8 μg/m3. This study shows that aerosolized fentanyl does not cause sensory and pulmonary irritation, and since the RD50 and LC50 are very close with a low safety margin, this type of sedative should not be used as an incapacitating agent. 相似文献
955.
Podaralla Satheesh Kumar Tulsi Ram Saini Durairaj Chandrasekar Venkata Kashyap Yellepeddi Sistla Ramakrishna Prakash V. Diwan 《Drug delivery》2013,20(8):517-523
Insulin stability during microencapsulation and subsequent release is essential for retaining its biological activity. The successful delivery of insulin relies on the proper selection of stabilizers in addition to other parameters. Attempts were made to address the problem with a few combination of stabilizers for maintaining the integrity of insulin during formulation and delivery. Insulin loaded nanoparticles with different stabilizers such as pluronic F68, trehalose, and sodium bicarbonate were prepared by the double emulsion evaporation method using two different copolymer ratios of poly(DL-lactide-co-glycolide) (50:50 and 85:15). The presence of stabilizers in the nanoparticles resulted in an increase in the particle size but a reduction of encapsulation efficiency. Insulin release rate was comparatively higher for the batches containing stabilizers when compared with controls for both the copolymer ratios. Also the presence of stabilizers resulted in sustained release of insulin resulting in prolonged reduction of blood glucose levels in streptozotocin induced diabetic rats. From the in vitro and in vivo studies, we concluded that a combination of stabilizers results in beneficial effects without compromising the advantages of delivery systems. 相似文献
956.
A series of biologically active N-(3-chloro-2-oxo-4-phenylazetidin-1-yl)/3-N-(4-oxo-2-arylthiazolidin-3-yl)-2-(methylsulfonamido)-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carboxamides derivatives have been synthesised in good yield. The structures of compounds have been established on the basis of IR, 1H, 13C NMR, and elemental analysis. The structure–activity relationships have been studied by screening of antimicrobial activity over a representative panel of bacterial and fungal strains using two-fold serial dilution method. All these synthesised compounds exhibited significant activities against all bacterial and fungal strains. 相似文献
957.
Janani Ravi Amita Sneh Konstantin Shilo Mohd W. Nasser Ramesh K. Ganju 《Oncotarget》2014,5(9):2475-2486
The endocannabinoid anandamide (AEA), a neurotransmitter was shown to have anti-cancer effects. Fatty acid amide hydrolase (FAAH) metabolizes AEA and decreases its anti-tumorigenic activity. In this study, we have analyzed the role of FAAH inhibition in non-small cell lung cancer (NSCLC). We have shown that FAAH and CB1 receptor which is activated by AEA are expressed in lung adenocarcinoma patient samples and NSCLC cell lines A549 and H460. Since the synthetic analogue of anandamide (Met-F-AEA) did not possess significant anti-tumorigenic effects, we used Met-F-AEA in combination with FAAH inhibitor URB597 which significantly reduced EGF (epidermal growth factor)-induced proliferative and chemotactic activities in vitro when compared to anti-tumorigenic activity of Met-F-AEA alone. Further analysis of signaling mechanisms revealed that Met-F-AEA in combination with URB597 inhibits activation of EGFR and its downstream signaling ERK, AKT and NF-kB. In addition, it inhibited MMP2 secretion and stress fiber formation. We have also shown that the Met-F-AEA in combination with URB597 induces G0/G1 cell cycle arrest by downregulating cyclin D1 and CDK4 expressions, ultimately leading to apoptosis via activation of caspase-9 and PARP. Furthermore, the combination treatment inhibited tumor growth in a xenograft nude mouse model system. Tumors derived from Met-F-AEA and URB597 combination treated mice showed reduced EGFR, AKT and ERK activation and MMP2/MMP9 expressions when compared to Met-F-AEA or URB597 alone. Taken together, these data suggest in EGFR overexpressing NSCLC that the combination of Met-F-AEA with FAAH inhibitor resulted in superior therapeutic response compared to individual compound activity alone. 相似文献
958.
The pharmacological importance of cannabinoids has been in study for several years. Cannabinoids comprise of (a) the active compounds of the Cannabis sativa plant, (b) endogenous as well as (c) synthetic cannabinoids. Though cannabinoids are clinically used for anti-palliative effects, recent studies open a promising possibility as anti-cancer agents. They have been shown to possess anti-proliferative and anti-angiogenic effects in vitro as well as in vivo in different cancer models. Cannabinoids regulate key cell signaling pathways that are involved in cell survival, invasion, angiogenesis, metastasis, etc. There is more focus on CB1 and CB2, the two cannabinoid receptors which are activated by most of the cannabinoids. In this review article, we will focus on a broad range of cannabinoids, their receptor dependent and receptor independent functional roles against various cancer types with respect to growth, metastasis, energy metabolism, immune environment, stemness and future perspectives in exploring new possible therapeutic opportunities. 相似文献
959.
960.
Increasing rates of preterm births coupled with better survival of these infants have resulted in higher prevalence of systemic and ocular complications associated with prematurity. In addition to retinopathy of prematurity, infants who are born preterm may suffer from severe visual impairment as a result of hypoxic ischemic encephalopathy, hypoglycemia, and other metabolic imbalances. The effect of these processes on the anterior visual pathway may result in optic atrophy, optic nerve hypoplasia or optic disc cupping and affection of the posterior visual pathway leads to cortical visual impairment (CVI). Other ocular associations include strabismus, nystagmus, and ocular motor abnormalities such as tonic down gaze and defective saccades and pursuits. Cortical and subcortical involvement also manifests as defects in functional vision and these have not yet been completely understood. Children with CVI may have visual field defects, photophobia, defective visual processing, and deficient color vision. Since most of these children also suffer from additional systemic disabilities, evaluation, and management remains a challenge. However, early diagnosis and initiation of rehabilitation therapy can prove to be of significant benefit in these children. 相似文献