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排序方式: 共有1678条查询结果,搜索用时 15 毫秒
101.
Sharma JB Jain S Mallika V Singh T Kumar A Arora R Murthy NS 《The American journal of clinical nutrition》2004,79(1):116-122
BACKGROUND: Daily oral iron supplementation during pregnancy fails to reduce the prevalence of anemia. However, 2 or 3 intramuscular doses of iron given at monthly intervals were recently found to be effective. OBJECTIVE: We compared the safety and efficacy in treating pregnancy anemia of 3 intramuscular doses of iron given at monthly intervals with those of daily oral iron supplementation. DESIGN: In a prospective, partially randomized study, 148 pregnant women received daily oral doses of 100 mg elemental Fe and 500 micro g folic acid, and 106 pregnant women received 3 intramuscular doses of 250 mg elemental Fe as iron dextran at 1-mo intervals and oral doses of 5 mg folic acid twice weekly. One hundred women in each group completed the study. Changes in hemoglobin, iron indicators, pregnancy outcomes, and birth weight were compared between the 2 groups. RESULTS: Hemoglobin and iron indicators improved significantly with both treatments. The increase in serum ferritin concentration after parenteral iron treatment was significantly higher than that after oral iron treatment. No significant differences between the 2 groups in pregnancy outcomes and birth weight were observed. Systemic side effects were more common in the parenteral iron group, whereas gastrointestinal side effects were more common in the oral iron group. CONCLUSIONS: The intramuscular administration of 3 doses of 250 mg Fe at monthly intervals appears to have good compliance and efficacy and may be used in women who cannot tolerate oral administration of iron. However, intramuscular administration of iron is appropriate only in hospital settings well equipped to treat anaphylactic crises. 相似文献
102.
Gayathri Narasimhan John Henderson Hien T Luong Namakkal Soorapan Rajasekaran Gangjian Qin Jianyi Zhang Prasanna Krishnamurthy 《Clinical and experimental pharmacology & physiology》2019,46(8):743-751
Obg‐like ATPase 1 (OLA1) that possesses both GTP and ATP hydrolyzing activities has been shown to be involved in translational regulation of cancer cell growth and survival. Also, GSK3β signalling has been implicated in cardiac development and disease. However, the role of OLA1 in pathological cardiac hypertrophy is unknown. We sought to understand the mechanism by which OLA1 regulates GSK3β‐β‐Catenin signalling and its functional significance in angiotensin‐II (ANG II)‐induced cardiac hypertrophic response. OLA1 function and its endogenous interaction with GSK3β/β‐catenin signalling in cultured human ventricular cardiomyocytes (AC16 cells) and mouse hearts (in vivo) was evaluated with/without ANG II‐stimulated hypertrophic response. ANG II administration in mice increases myocardial OLA1 protein expression with a corresponding increase in GSK3β phosphorylation and decrease in β‐Catenin phosphorylation. Cultured cardiomyocytes treated with ANG II show endogenous interaction between OLA1 and GSK3β, nuclear accumulation of β‐Catenin and significant increase in cell size and expression of hypertrophic marker genes such as atrial natriuretic factor (ANF; NPPA) and β‐myosin heavy chain (MYH7). Intriguingly, OLA1 inhibition attenuates the above hypertrophic response in cardiomyocytes. Taken together, our data suggest that OLA1 plays a detrimental role in hypertrophic response via GSK3β/β‐catenin signalling. Translation strategies to target OLA1 might potentially limit the underlying molecular derangements leading to left ventricular dysfunction in patients with maladaptive cardiac hypertrophy. 相似文献
103.
Sandhya Narasimhan Mayur Joshi Sowmya Parameswaran Pukhraj Rishi Vikas Khetan Suganeswari Ganesan Jyotirmay Biswas Natarajan Sundaram Janani Sreenivasan Sonali Verma Vanitha Krishnamurthy Krishnakumar Subramanian 《Indian journal of ophthalmology》2020,68(10):2160
Purpose:Vitreoretinal lymphoma (VRL) is the most common intraocular lymphoma (IOL). This can be either primary or secondary to the central nervous system lymphoma. The diagnosis of primary intraocular lymphoma (PIOL) currently relies on clinical diagnosis and cytological analysis of the vitreous or subretinal biopsy. Although most cases are diagnosed without much issue, the limited amount of vitreous fluid, subjectivity in cytological reporting, and special expertise in ocular pathology make the diagnosis challenging. MYD88 L265P mutation has been implicated to have diagnostic utility in PIOL. In this study, we screened consecutive vitreous biopsies for the presence of MYD88 L265P mutation to understand its diagnostic utility compared to conventional cytological analysis.Methods:Cytological analysis and MYD88 L265P mutation by PCR-based sequencing and restriction fragment length polymorphism (RFLP) were carried out on consecutive vitreous and subretinal biopsies collected from 21 patients. The diagnostic utility of the cytology and MYD88 L265P mutation analysis were compared.Results:Out of the 21 patients, 15 had clinical suspicion of having PIOL. Out of these suspected cases of PIOL, nine were confirmed on follow-up, while six were diagnosed as other intraocular pathologies. Diagnostic utility of MYD88 L265P mutation analysis revealed a sensitivity of 88.9%, specificity of 91.6%, positive and negative predictive value of 88.9% and 91.7%, respectively. Diagnostic accuracy of 90.5% was achieved with the mutation analysis that shows the superiority of MYD88 in both ruling in and ruling out PIOL. The diagnostic utility of MYD88 L265P mutation was superior to conventional cytological analysis.Conclusion:The analysis of MYD88 L265P mutation is reliable and efficient in the diagnosis of PIOL. 相似文献
104.
There has been considerable interest in the development of novel compounds with anticonvulsant, antioxidant, hormone antagonist, analgesic, anti-inflammatory, antiplatelet, antimalarial, antimicrobial, antimycobacterial, antitumoral, vasodilator, antiviral and anti-trypanosomal activities. Hydrazones possessing an azometine -NHN=CH- proton constitute an important class of compounds for new drug development. Therefore, many researchers have synthesized these compounds as target structures and evaluated their biological activities. These observations have been guiding for the development of new hydrazide derivatives that possess varied biological activities. 相似文献
105.
We report carbohydrate-anchored polyethylene sebacate (PES)-Gantrez® AN 119 Doxorubicin hydrochloride (Dox) nanoparticles (NPs) for enhanced anticancer efficacy. The carbohydrates Arabinogalactan (AGn), an adjuvant in anticancer chemotherapy and pullulan (Pul) reported to promote collagen synthesis, were selected as ligands. PES Dox NPs of an average size around 200?nm, greater than 20% w/w Dox loading and negative zeta potential were anchored with Pul, AGn, and Pul–AGn combination by simple incubation. Increase in particle size and zeta potential confirmed carbohydrate anchoring. FTIR confirmed ionic complexation of Dox and Gantrez® AN 119. DSC and XRD demonstrated amorphization of Dox. Higher Dox release in pH 5.5 as compared with pH 7.4 is beneficial for reduced systemic toxicity and enhanced drug release in tumors. Good in vitro serum stability and low hemolysis revealed suitability for intravenous administration. All NPs revealed circulation longevity in normal rats. Pul NPs revealed superior anticancer efficacy in vitro and an 11-fold enhancement in uptake in MCF-7 breast cancer cells. The greater efficacy in vivo is attributed to possible pullulan-mediated integrin receptor uptake and interaction with tumor collagen. Histopathology confirmed safety and suggested promise of Pul NPs in improved anticancer efficacy. 相似文献
106.
Anamitra Ghosh Monica R. Langley Dilshan S. Harischandra Matthew L Neal Huajun Jin Vellareddy Anantharam Joy Joseph Timothy Brenza Balaji Narasimhan Arthi Kanthasamy Balaraman Kalyanaraman Anumantha G. Kanthasamy 《Journal of neuroimmune pharmacology》2016,11(2):259-278
Mitochondrial dysfunction, oxidative stress and neuroinflammation have been implicated as key mediators contributing to the progressive degeneration of dopaminergic neurons in Parkinson’s disease (PD). Currently, we lack a pharmacological agent that can intervene in all key pathological mechanisms, which would offer better neuroprotective efficacy than a compound that targets a single degenerative mechanism. Herein, we investigated whether mito-apocynin (Mito-Apo), a newly-synthesized and orally available derivative of apocynin that targets mitochondria, protects against oxidative damage, glial-mediated inflammation and nigrostriatal neurodegeneration in cellular and animal models of PD. Mito-Apo treatment in primary mesencephalic cultures significantly attenuated the 1-methyl-4-phenylpyridinium (MPP+)-induced loss of tyrosine hydroxylase (TH)-positive neuronal cells and neurites. Mito-Apo also diminished MPP+-induced increases in glial cell activation and inducible nitric oxide synthase (iNOS) expression. Additionally, Mito-Apo decreased nitrotyrosine (3-NT) and 4-hydroxynonenol (4-HNE) levels in primary mesencephalic cultures. Importantly, we assessed the neuroprotective property of Mito-Apo in the MPTP mouse model of PD, wherein it restored the behavioral performance of MPTP-treated mice. Immunohistological analysis of nigral dopaminergic neurons and monoamine measurement further confirmed the neuroprotective effect of Mito-Apo against MPTP-induced nigrostriatal dopaminergic neuronal loss. Mito-Apo showed excellent brain bioavailability and also markedly attenuated MPTP-induced oxidative markers in the substantia nigra (SN). Furthermore, oral administration of Mito-Apo significantly suppressed MPTP-induced glial cell activation, upregulation of proinflammatory cytokines, iNOS and gp91phox in IBA1-positive cells of SN. Collectively, these results demonstrate that the novel mitochondria-targeted compound Mito-Apo exhibits profound neuroprotective effects in cellular and pre-clinical animal models of PD by attenuating oxidative damage and neuroinflammatory processes. 相似文献
107.
Deepika Sharma Pradeep Kumar Balasubramanian Narasimhan 《Medicinal chemistry research》2012,21(6):796-803
In this study, the coordination chemistry of the antibiotic, cefdinir, and its metal complexes with Cu (II) and Zn (II) was
described and characterized on the basis of analytical and spectral studies. The synthesized complexes were evaluated in vitro
for their antibacterial activity against Staphylococcus aureus, Bacillus subtilis, and Escherichia coli. The metal complexes possessed the better antibacterial activity against the selected species of bacteria than the free antibiotic
(cefdinir). The results were supported by the increase in log P values of metal complexes in comparison to the free ligand
cefdinir. The importance of these findings lies in the fact that these complexes could be applied in the treatment of common
bacterial infections. 相似文献
108.
Minocycline is a second‐generation semi‐synthetic derivative of tetracycline and has well‐known anti‐bacterial effects. The drug possesses anti‐inflammatory, anti‐oxidant, anti‐apoptotic and immunomodulatory effects. The drug is widely used in bacterial infections and non‐infectious conditions such as acne, dermatitis, periodontitis and neurodegenerative conditions. Minocycline was shown to have antiviral activity in vitro and also against different viruses in some animal models. Some studies have been done on human patients infected with Human Immunodeficiency Virus. We have review the available data regarding minocycline activity as an antiviral agent. 相似文献
109.
Development of 2‐(Substituted Benzylamino)‐4‐Methyl‐1, 3‐Thiazole‐5‐Carboxylic Acid Derivatives as Xanthine Oxidase Inhibitors and Free Radical Scavengers 下载免费PDF全文
Md Rahmat Ali Suresh Kumar Obaid Afzal Nishtha Shalmali Manju Sharma Sandhya Bawa 《Chemical biology & drug design》2016,87(4):508-516
A series of 2‐(substituted benzylamino)‐4‐methylthiazole‐5‐carboxylic acid was designed and synthesized as structural analogue of febuxostat. A methylene amine spacer was incorporated between the phenyl ring and thiazole ring in contrast to febuxostat in which the phenyl ring was directly linked with the thiazole moiety. The purpose of incorporating methylene amine was to provide a heteroatom which is expected to favour hydrogen bonding within the active site residues of the enzyme xanthine oxidase. The structure of all the compounds was established by the combined use of FT‐IR, NMR and MS spectral data. All the compounds were screened in vitro for their ability to inhibit the enzyme xanthine oxidase as per the reported procedure along with DPPH free radical scavenging assay. Compounds 5j, 5k and 5l demonstrated satisfactory potent xanthine oxidase inhibitory activities with IC50 values, 3.6, 8.1 and 9.9 μm , respectively, whereas compounds 5k , 5n and 5p demonstrated moderate antioxidant activities having IC50 15.3, 17.6 and 19.6 μm , respectively, along with xanthine oxidase inhibitory activity. Compound 5k showed moderate xanthine oxidase inhibitory activity as compared with febuxostat along with antioxidant activity. All the compounds were also studied for their binding affinity in active site of enzyme (PDB ID‐1N5X). 相似文献
110.
Shen BQ Bumbaca D Saad O Yue Q Pastuskovas CV Khojasteh SC Tibbitts J Kaur S Wang B Chu YW LoRusso PM Girish S 《Current drug metabolism》2012,13(7):901-910
Trastuzumab emtansine (T-DM1) is an antibody-drug conjugate in clinical development for the treatment of human epidermal growth factor receptor 2 (HER2)-positive cancers. Herein, we describe a series of studies to assess T-DM1 absorption, distribution, metabolism, and excretion (ADME) in rats as well as to assess human exposure to T-DM1 catabolites. Following administration of unlabeled and radiolabeled T-DM1 in female Sprague Dawley rats as a single dose, plasma, urine, bile and feces were assessed for mass balance, profiling and identification of catabolites. In rats, the major circulating species in plasma was T-DM1, while DM1 concentrations were low (1.08 to 15.6 ng/mL). The major catabolites found circulating in rat plasma were DM1, [N-maleimidomethyl] cyclohexane-1- carboxylate-DM1 (MCC-DM1), and Lysine-MCC-DM1. These catabolites identified in rats were also detected in plasma samples from patients with HER2-positive metastatic breast cancer who received single-agent T-DM1 (3.6 mg/kg every 3 weeks) in a phase 2 clinical study. There was no evidence of tissue accumulation in rats or catabolite accumulation in human plasma following multiple dosing. In rats, T-DM1 was distributed nonspecifically to the organs without accumulation. The major pathway of DM1-containing catabolite elimination in rats was the fecal/biliary route, with up to 80% of radioactivity recovered in the feces and 50% in the bile. The rat T-DM1 ADME profile is likely similar to the human profile, although there may be differences since trastuzumab does not bind the rat HER2- like receptor. Further research is necessary to more fully understand the T-DM1 ADME profile in humans. 相似文献