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51.
Niloufar Abdollahian Hamideh Ghazizadeh Maryam MohammadiBajgiran Mehran Pashirzad Mahdiyeh Yaghooti Khorasani Mary Kathryn Bohn Shannon Steele Fatemeh Roudi Atieh Kamel Khodabandeh Sara Ghazi Zadeh Iman AlamiArani Seyede Negin Badakhshan Habibollah Esmaily Gordon A. Ferns Reza AssaranDarban Khosrow Adeli Majid GhayourMobarhan 《Journal of cellular and molecular medicine》2023,27(1):158
Age and sex need to be considered in the establishment of reference intervals (RIs), especially in early life when there are dynamic physiological changes. Since data for important biomarkers in healthy neonates and infants are limited, particularly in Iranian populations, we have determined age‐specific RIs for 7 laboratory biochemical parameters. This cross‐sectional study comprised a total of 344 paediatric participants (males: 158, females: 186) between the ages of 3 days and 30 months (mean age: 12.91 ± 7.15 months). Serum levels of creatinine, urea, uric acid, calcium, phosphate, vitamin D and high‐sensitivity C‐reactive protein (hs‐CRP) were measured using an Alpha classic‐AT plus auto‐analyser. We determined age‐specific RIs using CLSI Ep28‐A3 and C28‐A3 guidelines. No sex partitioning was required for any of the biomarkers. Age partitioning was required for kidney function tests and phosphate. The serum concentration of urea and creatinine increased with age, while phosphate and uric acid decreased with age. Age partitioning was not required for serum calcium, vitamin D, and hs‐CRP, which remained relatively constant throughout the age range. Age‐specific RIs for 7 routine biochemical markers were determined to address critical gaps in RIs in early life to help improve clinical interpretation of blood test results in young children, including neonates. Established age partitions demonstrate the biochemical changes that take place during child growth and development. These novel data will ultimately better disease management in the Iranian paediatric population and can be of value to clinical and hospital laboratories with similar populations. 相似文献
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Haidari M Zhang W Chen Z Ganjehei L Mortazavi A Warier N Vanderslice P Dixon RA 《Experimental cell research》2012,318(14):1673-1684
Vascular endothelial cadherin (VE-cad) tyrosine (Tyr) phosphorylation has been implicated in the disruption of adherens junctions (AJs) induced by inflammatory reactions. The impacts of statins on integrity of AJs and VE-cad Tyr phosphorylation have not been explored. The effects of atorvastatin on IL-1β and monocyte-induced VE-cad Tyr phosphorylation in human umbilical vein endothelial cells (ECs) were studied. In ECs treated with interleukin (IL)-1β for 30 min, VE-cad Tyr phosphorylation, dissociation of the VE-cad/β-catenin complex and transendothelial migration (TEM) of monocytes were increased. These processes were mediated by activation of HRas and RhoA that leads to phosphorylation of myosin light chain (MLC). Atorvastatin inhibited IL-1β-induced Tyr phosphorylation of VE-cad by inhibiting RhoA and by dephosphorylating MLC. The attenuating effect of atorvastatin on VE-cad Tyr phosphorylation was reversed when RhoA was activated or MLC phosphatase was inhibited. Furthermore, inhibiting farnesyl transferase or geranylgeranyl transferase reproduced the inhibitory effects of atorvastatin on VE-cad Tyr phosphorylation. In addition, atorvastatin inhibited monocyte-induced VE-cad Tyr phosphorylation in ECs and attenuated IL-1β-induced TEM of monocytes. Our study introduces a novel pleiotropic effect of atorvastatin and suggests that statins protect the integrity of AJs in ECs by inhibiting RhoA-mediated Tyr phosphorylation of VE-cad. 相似文献
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BA Seinstra L Defreyne B Lambert MG Lam HM Verkooijen KJ van Erpecum B van Hoek AR van Erkel MJ Coenraad I Al Younis H van Vlierberghe MA van den Bosch 《Trials》2012,13(1):144
ABSTRACT: BACKGROUND: Hepatocellular carcinoma is a primary malignant tumor of the liver that accounts for an important health problem worldwide. Only 10 to 15% of hepatocellular carcinoma patients are suitable candidates for treatment with curative intent, such as hepatic resection and liver transplantation. A majority of patients have locally advanced, liver restricted disease (Barcelona Clinic Liver Cancer (BCLC) staging system intermediate stage). Transarterial loco regional treatment modalities offer palliative treatment options for these patients; transarterial chemoembolization (TACE) is the current standard treatment. During TACE, a catheter is advanced into the branches of the hepatic artery supplying the tumor, and a combination of embolic material and chemotherapeutics is delivered through the catheter directly into the tumor. Yttrium-90 radioembolization (90Y-RE) involves the transarterial administration of minimally embolic microspheres loaded with Yttrium-90, a beta-emitting isotope, delivering selective internal radiation to the tumor. 90Y-RE is increasingly used in clinical practice for treatment of intermediate stage hepatocellular carcinoma, but its efficacy has never been prospectively compared to that of the standard treatment (TACE). In this study, we describe the protocol of a multicenter randomized controlled trial aimed at comparing the effectiveness of TACE and 90Y-RE for treatment of patients with unresectable (BCLC intermediate stage) hepatocellular carcinoma.Methods/designIn this pragmatic randomized controlled trial, 140 patients with unresectable (BCLC intermediate stage) hepatocellular carcinoma, with Eastern Cooperative Oncology Group performance status 0 to 1 and Child-Pugh A to B will be randomly assigned to either 90Y-RE or TACE with drug eluting beads. Patients assigned to 90Y-RE will first receive a diagnostic angiography, followed by the actual transarterial treatment, which can be divided into two sessions in case of bilobar disease. Patients assigned to TACE will receive a maximum of three consecutive transarterial treatment sessions. Patients will undergo structural follow-up for a timeframe of two years post treatment. Post procedural magnetic resonance imaging (MRI) will be performed at one and three months post trial entry and at three-monthly intervals thereafter for two years to assess tumor response. Primary outcome will be time to progression. Secondary outcomes will be overall survival, tumor response according to the modified RECIST criteria, toxicities/adverse events, treatment related effect on total liver function, quality of life, treatment-related costs and cost-effectiveness.Trial registrationNCT01381211. 相似文献
56.
A short RNA covalently associated with nascent DNA has been isolated after synthesis in vitro with labeled ribonucleoside triphosphates and the removal of DNA by DNAase digestion. The RNA migrates in polyacrylamide gels or chromatographs on DEAE-Sephadex columns as a relatively discrete oligonucleotide 8–11 nucleotides in length. The RNA is associated primarily with nascent DNA with stoichiometry of approximately one per DNA chain. The RNA has a triphosphate group at the 5′ end and 2 or 3 deoxynucleotide residues at the 3′ end that are not removed by DNAase. These results further support a role for the RNA as an initiator of discontinuous DNA synthesis. Examination of sequences present at the 3′ end of the RNA using RNAase to effect transfer of 32PO4 from 32P-labeled DNA to covalently attached RNA indicates that a diverse, rather than unique, set of sequences are present in the RNA. 相似文献
57.
Margaret S. Landis Shobha Bhattachar Mehran Yazdanian John Morrison 《AAPS PharmSciTech》2018,19(1):1-10
This commentary reflects the collective view of pharmaceutical scientists from four different organizations with extensive experience in the field of drug discovery support. Herein, engaging discussion is presented on the current and future approaches for the selection of the most optimal and developable drug candidates. Over the past two decades, developability assessment programs have been implemented with the intention of improving physicochemical and metabolic properties. However, the complexity of both new drug targets and non-traditional drug candidates provides continuing challenges for developing formulations for optimal drug delivery. The need for more enabled technologies to deliver drug candidates has necessitated an even more active role for pharmaceutical scientists to influence many key molecular parameters during compound optimization and selection. This enhanced role begins at the early in vitro screening stages, where key learnings regarding the interplay of molecular structure and pharmaceutical property relationships can be derived. Performance of the drug candidates in formulations intended to support key in vivo studies provides important information on chemotype-formulation compatibility relationships. Structure modifications to support the selection of the solid form are also important to consider, and predictive in silico models are being rapidly developed in this area. Ultimately, the role of pharmaceutical scientists in drug discovery now extends beyond rapid solubility screening, early form assessment, and data delivery. This multidisciplinary role has evolved to include the practice of proactively taking part in the molecular design to better align solid form and formulation requirements to enhance developability potential. 相似文献
58.
As recently demonstrated, a placebo procedure in motor performance increases force production and changes the excitability of the corticospinal system, by enhancing the amplitude of the motor evoked potentials (MEP) and reducing the duration of the cortical silent period (CSP). However, it is not clear whether these neurophysiological changes are related to the behavioural outcome (increased force) or to a general effect of expectation. To clarify this, we investigated the nocebo effect, in which the induced expectation decreases force production. Two groups of healthy volunteers (experimental and control) performed a motor task by pressing a piston with the right index finger. To induce a nocebo effect in the experimental group, low frequency transcutaneous electrical nerve stimulation (TENS) was applied over the index finger with instructions of its detrimental effects on force. To condition the subjects, the visual feedback on their force level was surreptitiously reduced after TENS. Results showed that the experimental group reduced the force, felt weaker and expected a worse performance than the control group, who was not suggested about TENS. By applying transcranial magnetic stimulation over the primary motor cortex, we found that while MEP amplitude remained stable throughout the procedure in both groups, the CSP duration was shorter in the experimental group after the nocebo procedure. The CSP reduction resembled previous findings on the placebo effect, suggesting that expectation of change in performance diminishes the inhibitory activation of the primary motor cortex, independently of the behavioural outcome. 相似文献
59.
Mohsen Akbari Mehran Torki Keyomars Kaviani 《International journal of biometeorology》2016,60(3):447-454
60.
Altered Deoxyribonucleic Acid Polymerase Activity in a Methyl Methanesulfonate-Sensitive Mutant of Bacillus subtilis 总被引:5,自引:5,他引:5 下载免费PDF全文
Kenneth B. Gass Thomas C. Hill Mehran Goulian Bernard S. Strauss Nicholas R. Cozzarelli 《Journal of bacteriology》1971,108(1):364-374
Of six deoxyribonucleic acid repair mutants of Bacillus subtilis assayed for deoxyribonucleic acid polymerase, only the methyl methanesulfonate-sensitive and ultraviolet light-sensitive mutant JB1-49(59) has impaired polymerase activity. Extracts prepared by sonic treatment or gentle lysis had about 10% of the wild-type activity with poly d(A-T), an alternating copolymer of deoxyadenylate and deoxythymidylate, used as template. The sensitivity to methyl methanesulfonate and ultraviolet light and the low level of polymerase activity transformed and reverted together, indicating that the two characteristics are a pleiotropic manifestation of a single mutation. Mixed extract and kinetic experiments mitigated against an altered nuclease activity as the enzymatic consequence of the mutation. Also, the mutant and wild type activities were stimulated equally by Escherichia coli exonuclease III. The residual activity in the mutant showed several differences from the wild-type activity: it purified differently, was more sensitive to sulfhydryl reagents, and displayed a different template specificity. We tentatively conclude that either the mutation in JB1-49(59) has introduced a qualitative as well as a quantitative change in the polymerase or the wild type contains two distinct polymerases, one of which is missing in the mutant. 相似文献