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81.
82.
The gold(I) complexes of the general formula [Au(L(n))(PPh(3))]·xH(2)O (1-8; n = 1-8 and x = 0-1.5), where L(n) stands for a deprotonated form of the benzyl-substituted derivatives of 6-benzylaminopurine, were prepared, thoroughly characterized (elemental analyses, FT-IR, Raman and multinuclear NMR spectroscopy, ESI+ mass spectrometry, conductivity, DFT calculations), and studied for their in vitro cytotoxicity and in vitro and in vivo anti-inflammatory effects on LPS-activated macrophages (derived from THP-1 cell line) and using the carrageenan-induced hind paw edema model on rats. The obtained results indicate that the representative complexes (1, 3, 6) exhibit a strong ability to reduce the production of pro-inflammatory cytokines TNF-α, IL-1β and HMGB1 without influence on the secretion of anti-inflammatory cytokine IL-1RA in the LPS-activated macrophages. The complexes also significantly influence the formation of edema, caused by the intraplantar application of polysaccharide λ-carrageenan to rats in vivo. All the tested complexes showed similar or better biological effects as compared with Auranofin, but contrary to Auranofin they were found to be less cytotoxic in vitro. The obtained results clearly indicate that the gold(I) complexes behave as very effective anti-inflammatory agents and could prove to be useful for the treatment of difficult to treat inflammatory diseases such as rheumatoid arthritis.  相似文献   
83.
Acyclic nucleoside phosphonates (ANP) are virostatics effective against viruses like hepatitis B virus and human immunodeficiency virus. Our previous reports indicated immunomodulatory activities of ANP in mouse and human innate immune cells. Recently, evidence has increased that hepatocytes may play an active role in immune regulation of the liver homeostasis or injury. In this study we investigated possible immunomodulatory effects of ANP on rat hepatocytes and macrophages. Nitric oxide (NO) production and secretion of cytokines (IL-1α, IL-1β, IL-2, IL-4, IL-6, IL-10, IL-13, IL-18, IFN-γ, TNF-α and GM-CSF) were analyzed under in vitro conditions. Test compounds included: 9-[2-(phosphonomethoxy)ethyl]adenine (PMEA; adefovir); 9-[2-(phosphonomethoxy)ethyl]-2,6-diaminopurine (PMEDAP); (R)- and (S)-enantiomers of 9-[2-(phosphonomethoxy)propyl]adenine [(R)-PMPA; tenofovir] and [(S)-PMPA]; 9-[2-(phosphonomethoxy)propyl]-2,6-diaminopurine [(R)-PMPDAP] and [(S)-PMPDAP]. The group of test compounds also included their N(6)-substituted derivatives. Some of ANP which are able to induce NO production and cytokine secretion in cultured macrophages possess the same immunobiological activity in isolated hepatocytes. The extent of responses is in range of LPS/IFN-γ stimulation in both types of cells. The effects of active ANP on NO expression and cytokine secretion are dose- and time-dependent. Interestingly, the spectrum of detected cytokines induced by ANP is broader in hepatocytes. The results also confirm immunomodulatory effects of some ANP on rodent macrophages. Moreover, we demonstrate for the first time immunobiological reactivity of primary rat hepatocytes induced by exogenous ANP compounds. The potential of hepatocytes to synthesize cytokines can contribute to better understanding of liver immune function and can serve for pharmacological intervention in liver diseases.  相似文献   
84.
Alterations in kinase genes such as NTRK1/2/3, RET, and BRAF underlie infantile fibrosarcoma (IFS), the emerging entity ‘NTRK-rearranged spindle cell neoplasms’ included in the latest WHO classification, and a growing set of tumors with overlapping clinical and pathological features. In this study, we conducted a comprehensive clinicopathological and molecular analysis of 22 cases of IFS and other kinase gene-altered spindle cell neoplasms affecting both pediatric and adult patients. Follow-up periods for 16 patients ranged in length from 10 to 130 months (mean 38 months). Six patients were treated with targeted therapy, achieving a partial or complete response in five cases. Overall, three cases recurred and one metastasized. Eight patients were free of disease, five were alive with disease, and two patients died. All cases showed previously reported morphological patterns. Based on the cellularity and level of atypia, cases were divided into three morphological grade groups. S100 protein and CD34 were at least focally positive in 12/22 and 14/22 cases, respectively. Novel PWWP2A::RET, NUMA1::RET, ITSN1::RAF1, and CAPZA2::MET fusions, which we report herein in mesenchymal tumors for the first time, were detected by RNA sequencing. Additionally, the first uterine case with BRAF and EGFR mutations and CD34 and S100 co-expression is described. DNA sequencing performed in 13 cases uncovered very rare additional genetic aberrations. The CNV profiles showed that high-grade tumors demonstrate a significantly higher percentage of copy number gains and losses across the genome compared with low- and intermediate-grade tumors. Unsupervised clustering of the tumors’ methylation profiles revealed that in 8/9 cases, the methylation profiles clustered with the IFS methylation class, irrespective of their clinicopathological or molecular features. © 2024 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.  相似文献   
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86.
Needle-shaped crystals are a common occurrence in many pharmaceutical and fine chemicals processes. Even if the particle size distribution (PSD) obtained in a crystallization step can be controlled by the crystal growth kinetics and hydrodynamic conditions, further fluid-solid separation steps such as filtration, filter washing, drying, and subsequent solids handling can often lead to uncontrolled changes in the PSD due to breakage. In this contribution we present a combined computational and experimental methodology for determining the breakage kernel and the daughter distribution functions of needle-shaped crystals, and for population balance modeling of their breakage. A discrete element model (DEM) of needle-shaped particle breakage was first used in order to find out the appropriate types of the breakage kernel and the daughter distribution functions. A population balance model of breakage was then formulated and used in conjunction with experimental data in order to determine the material-specific parameters appearing in the breakage functions. Quantitative agreement between simulation and experiment has been obtained.  相似文献   
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Anthracycline derivatives are among the most effective antineoplastic drugs but their therapeutic use is limited by their adverse effects. The cardiac side-effects of antineoplastic drugs were investigated in rabbits in vivo from the viewpoint of release of cardiac troponin T (cTnT) measured by Elecsys Troponin T STAT immunoassay (Boehringer Mannheim, Germany). No increase in cTnT was found following administration of a single dose of daunorubicin (3 mg/kg i.v., n = 4). During development of daunorubicin-induced cardiomyopathy (daunorubicin 3 mg/kg i.v., once a week; maximum nine administrations, n = 7), the levels of cTnT were within the physiological range (i.e. cTnT < 0.1 μg/1) at the beginning of the experiment and before and after the 5th administration, but the pathological values of cTnT after the 8th administration in 43% animals (0.22 ± 0.08 μg/l) correlated with their premature death. In the control group, the levels of cTnT were always lower than 0.1 μg/l during the experiment. Following administration of a new antineoplastic drug – Oracin {6-[2-(2-hydroxyethyl) aminoethyl]-5,11-dioxo-5,6-dihydro-11H-indeno [1,2-c]-isoquinoline hydrochloride, 10 mg/kg i.v., once weekly, ten administrations, n = 7}, there was no increase in cTnT levels. These findings correlated with the PEP: LVET index, histological examination and no animal succumbing to premature death. It is possible to conclude that cTnT is a useful marker for the prediction of experimentally induced anthracycline cardiomyopathy and for the evaluation of cardiotoxic (and, possibly, cardioprotective) effects of new drugs in rabbits. Received: 1 October 1998 / Accepted: 23 November 1998  相似文献   
90.
Cranial sutures join the many bones of the skull. They are therefore points of weakness and consequently subjected to the many mechanical stresses affecting the cranium. However, the way in which this impacts their morphological complexity remains unclear. We examine the intrinsic and extrinsic mechanisms of human sagittal sutures by quantifying the morphology from 107 individuals from archaeological populations spanning the Mesolithic to Middle ages, using standardized two-dimensional photographs. Results show that the most important factor determining sutural complexity appears to be the position along the cranial vault from the junction with the coronal suture at its anterior-most point to the junction with the lambdoid suture at its posterior-most point. Conversely, factors such as age and lifeways show few trends in complexity, the most significant of which is a lower complexity in the sutures of Mesolithic individuals who consumed a tougher diet. The simple technique used in this study therefore allowed us to identify that, taken together, structural aspects play a more important role in defining the complexity of the human sagittal suture than extrinsic factors such as the mechanical forces imposed on the cranium by individuals' diet.  相似文献   
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