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1.
M. G. S  rensen 《Biomarkers》2007,12(3):266-286
Although several treatments for osteoporosis exist, further understanding of the mode of action of current treatments, as well as development of novel treatments, are of interest. Thus, preclinical models of osteoporosis are very useful, as they provide the possibility for gaining knowledge about the cellular mechanisms underlying the disease and for studying pharmaceutical prevention or intervention of the disease in simple and strictly controlled systems. In this review, we present a comprehensive collection of studies using biochemical markers of bone turnover for investigation of preclinical models of osteoporosis. These range from pure and simple in vitro systems, such as osteoclast cultures, to ex vivo models, such as cultures of embryonic murine tibiae and, finally, to in vivo models, such as ovariectomy and orchidectomy of rats. We discuss the relevance of the markers in the individual models, and compare their responses to those observed using 'golden standard' methods.  相似文献   

2.
Glycation is an important protein modification that could potentially affect bioactivity and molecular stability, and glycation of therapeutic proteins such as monoclonal antibodies should be well characterized. Glycated protein could undergo further degradation into advance glycation end (AGE) products. Here, we review the root cause of glycation during the manufacturing, storage and in vivo circulation of therapeutic antibodies, and the current analytical methods used to detect and characterize glycation and AGEs, including boronate affinity chromatography, charge-based methods, liquid chromatography-mass spectrometry and colorimetric assay. The biological effects of therapeutic protein glycation and AGEs, which ranged from no affect to loss of activity, are also discussed.  相似文献   

3.
Although several treatments for osteoporosis exist, further understanding of the mode of action of current treatments, as well as development of novel treatments, are of interest. Thus, preclinical models of osteoporosis are very useful, as they provide the possibility for gaining knowledge about the cellular mechanisms underlying the disease and for studying pharmaceutical prevention or intervention of the disease in simple and strictly controlled systems. In this review, we present a comprehensive collection of studies using biochemical markers of bone turnover for investigation of preclinical models of osteoporosis. These range from pure and simple in vitro systems, such as osteoclast cultures, to ex vivo models, such as cultures of embryonic murine tibiae and, finally, to in vivo models, such as ovariectomy and orchidectomy of rats. We discuss the relevance of the markers in the individual models, and compare their responses to those observed using ‘golden standard’ methods.  相似文献   

4.
Boron Neutron Capture Therapy (BNCT) is a binary radiotherapy method developed to treat patients with certain malignant tumours. To date, over 300 treatments have been carried out at the Finnish BNCT facility in various on-going and past clinical trials. In this technical review, we discuss our research work in the field of medical physics to form the groundwork for the Finnish BNCT patient treatments, as well as the possibilities to further develop and optimize the method in the future. Accordingly, the following aspects are described: neutron sources, beam dosimetry, treatment planning, boron imaging and determination, and finally the possibilities to detect the efficacy and effects of BNCT on patients.  相似文献   

5.
Huang X  Cormier JN  Pisters PW 《Biometrics》2006,62(3):901-909
In the treatment of cancer, patients commonly receive a variety of sequential treatments. The initial treatments administered following diagnosis can vary, as well as subsequent salvage regimens given after disease recurrence. This article considers the situation where neither initial treatments nor salvage treatments are randomized. Assuming there are no unmeasured confounders, we estimate the joint causal effects on survival of initial and salvage treatments, that is, the effects of two-stage treatment sequences. For each individual treatment sequence, we estimate the survival distribution function and the mean restricted survival time. Different treatment sequences are then compared using these estimates and their corresponding covariances. Simulation studies were conducted to evaluate the performance of the methods, including their sensitivity to the violation of the assumption of no unmeasured confounders. The methods are illustrated by a retrospective study of patients with soft tissue sarcoma, which motivated this research.  相似文献   

6.
High-risk, clinically localized prostate cancer represents a diverse disease entity. Patients who are considered to be at highest risk for biochemical failure after localized treatments may not be at significant risk for disea-sespecific mortality. In this review, an attempt will be made to define high-risk status and help identify patients at high risk for mortality after a diagnosis of localized prostate cancer. Subsequently, a review of monotherapy approaches as well as previously successful strategies utilizing multimodality therapy for high-risk disease will be presented. Finally, a synopsis will be given of several ongoing randomized clinical trials using the most effective systemic therapies in the adjuvant setting following thorough local treatments such as radical prostatectomy. This review will provide a glimpse into the future and describe the tools that it is hoped will improve further upon the results of surgical monotherapy for high-risk, localized prostate cancer.  相似文献   

7.
为了明确施用稀土镧和钕的叶面肥对江淮丘陵和黄河故道葡萄园节肢动物群落多样性和稳定性的影响,通过系统调查和t检验得出,肥东县和萧县两地镧和钕与清水(CK1)和醋液(CK2)之间,捕食性天敌的物种数和个体数、植食性昆虫物种数和个体数和总群落的多样性指数差异均不显著。总群落物种数与个体数的比值(稳定性值),肥东镧和钕与CK1之间t值为0.5592和1.0922,与CK2之间t值为1.2407和1.9178;萧县镧和钕与CK1之间t值为0.3533和0.8969,与CK2之间的t值为0.7067和0.4484;t值均小于t0.05(2.07),其群落稳定性差异均不显著,表明镧和钕叶面肥对葡萄园节肢动物群落多样性和稳定性影响不显著。对12次调查的捕食性天敌和植食性昆虫的物种数比值(Sn/Sp)进行分析,肥东喷镧和喷钕处理与CK1之间Sn/Sp的比值t检验的t值为0.5111和0.1499,与CK2的t值为0.1146和0.2466,CK1与CK2的t值为0.3476;萧县喷镧和喷钕处理与CK1之间Sn/Sp的比值t检验的t值为0.0976和0.0547,与CK2的t值为0.0975和0.1749,CK1与CK2的t值为0.2337,t值均小于t0.05,他们之间差异均不显著,表明两地两种稀土叶面肥对葡萄园节肢动物群落内食物网络关系的复杂性影响不显著。对12次调查捕食性天敌和植食性昆虫的个体数比值(Sa/Sb)进行分析,肥东喷镧和喷钕处理与CK1之间Sa/Sb的比值t检验的t值为0.9427和0.9727,与CK2的t值为0.5023和0.5342,CK1与CK2的t值为0.4957;萧县喷镧和喷钕处理与CK1之间Sa/Sb的比值t检验的t值为0.8820和0.0345,与CK2的t值为0.0741和1.0572,CK1与CK2的t值为0.8571,t值均小于t0.05,它们之间差异均不显著,表明两地两种稀土叶面肥对葡萄园节肢动物群落内食物网络关系的益害比影响不显著。  相似文献   

8.
In recent years, stem cell-mediated therapies have gained considerable ground as potential treatments for a wide variety of brain pathologies including traumatic brain injury, stroke and neurodegenerative diseases. Despite extensive preclinical studies, many of these therapies have not been fully translated into viable clinical approaches. This is partly due to our inability to reliably track and monitor transplanted stem cells longitudinally over long periods of time in vivo. In this review, we discuss the predominant histological cell tracing methodologies, such as immunohistochemistry, and fluorescent cellular dyes and proteins, and compare them to emerging cellular imaging technologies. We show that advances in magnetic resonance imaging (MRI) have resulted in opportunities to use this technology to further our understanding of stem cell characteristics and behaviors in vivo. While MRI may not completely replace conventional cell tracking methods in pre-clinical, mechanistic work, it is clear that it has the potential to function as a powerful diagnostic tool for tracking stem cell migration and survival as well as for evaluating the efficacy of stem cell-mediated therapies.  相似文献   

9.
钙在控制水果采后病害中的应用   总被引:2,自引:0,他引:2  
钙在果实生长发育中起着非常重要的作用。果实的许多生理失调和病害都与钙在水果组织中的含量有关。钙处理与气调、热处理、生物防治等联用在减少果实采后病害方面发挥了显著的作用。主要论述钙在控制水果采后病害中的作用机理、钙处理的方法、影响果实钙吸收的因素、以及钙与其它防病方法联用的效果。对于钙处理中可能出现的问题 ,提出了一些可行的解决方法  相似文献   

10.
钙在果实生长发育中起着非常重要的作用。果实的许多生理失调和病害都与钙在水果组织中的含量有关。钙处理与气调、热处理、生物防治等联用在减少果实采后病害方面发挥了显著的作用。主要论述钙在控制水果采后病害中的作用机理、钙处理的方法、影响果实钙吸收的因素、以及钙与其它防病方法联用的效果。对于钙处理中可能出现的问题,提出了一些可行的解决方法。  相似文献   

11.
In this, the fourth installment of our annual Hot Topics review on mRNA translation and aging, we have decided to expand our scope to include recent findings related to the role of TOR signaling in aging. As new data emerge, it is clear that TOR signaling acts upstream of mRNA translation, as well as a variety of other cellular processes, to modulate longevity and healthspan in evolutionarily diverse species. This Hot Topics review will cover important new findings in this area that have occurred over the past year. These include the demonstration that the TOR substrate ribosomal S6 kinase modulates longevity in mammals, the potential for TOR inhibitors as therapeutic treatments for Alzheimer's disease, and further studies emphasizing the importance of differential translation of specific mRNAs for healthy aging and enhanced longevity.  相似文献   

12.
Patterns of histone post-translational modifications (PTMs) and DNA modifications establish a landscape of chromatin states with regulatory impact on gene expression, cell differentiation and development. These diverse modifications are read out by effector protein complexes, which ultimately determine their functional outcome by modulating the activity state of underlying genes. From genome-wide studies employing high-throughput ChIP-Seq methods as well as proteomic mass spectrometry studies, a large number of PTMs are known and their coexistence patterns and associations with genomic regions have been mapped in a large number of different cell types. Conversely, the molecular interplay between chromatin effector proteins and modified chromatin regions as well as their resulting biological output is less well understood on a molecular level. Within the last decade a host of chemical approaches has been developed with the goal to produce synthetic chromatin with a defined arrangement of PTMs. These methods now permit systematic functional studies of individual histone and DNA modifications, and additionally provide a discovery platform to identify further interacting nuclear proteins. Complementary chemical- and synthetic-biology methods have emerged to directly observe and modulate the modification landscape in living cells and to readily probe the effect of altered PTM patterns on biological processes. Herein, we review current methodologies allowing chemical and synthetic biological engineering of distinct chromatin states in vitro and in vivo with the aim of obtaining a molecular understanding of histone and DNA modification function. This article is part of a Special Issue entitled: Molecular mechanisms of histone modification function.  相似文献   

13.
We investigated general effects of ecological restoration treatments on soil function in frequent‐fire forests of the western United States using a systematic review methodology. We searched numerous publication databases for original research papers and used well‐defined criteria developed a priori to select papers for review. We used meta‐analysis and qualitative summaries to compare reported responses of macronutrients, nitrogen cycling, and soil respiration among tree thinning (thin), prescribed fire (burn), and thinning plus prescribed fire treatments (composite). Results of meta‐analysis showed that mean differences in macronutrients were consistently higher in composite treatments (standardized using controls) when compared to thin‐only and burn‐only treatments. Mean responses related to nitrogen cycling showed similar patterns, with significant increases detected in composite treatments for all nitrogen cycling variables (mineralization, ammonification, and nitrification) and insignificant responses for the majority of the burn‐only and thin‐only treatments. Mean difference in response for soil respiration following composite treatments showed increases as compared to the controls, and no significant differences were detected in response to burn‐ and thin‐only treatments. While soil function, nutrient cycling, and soil respiration differed among treatments, the most significant effects were observed for nitrogen and carbon responses, net mineralization and nitrification, ammonium availability, and soil respiration rate, which experienced the greatest increase following treatments that were both thinned and burned.  相似文献   

14.
Medicinal plants are a two-edged sword that might be exploited as a treatment specific dosage, and as deadly poisonous substances to commit murder or suicide when administered in high doses. Forensic experts can collect traces and residual materials from these toxic medicinal plants at a crime scene as forensic evidence. Further, more investigations need to be deeply implemented to in the future to understand the significance of medicinal plants in forensic investigations to detect these criminal offenses. Additionally, to provides a deep understanding of chemical substances that can impact human life positively or negatively with different doses as well as identifying the optimal or overdose concentrations for either treatments or poisonous effects using recent biotechnological approaches. This review aims to illustrate different contributions and the significance of medicinal plants in the field and further employment in the context of forensic science, especially in the Kingdom of Saudi Arabia.  相似文献   

15.
Athletes spend a much greater proportion of their time recovering than they do in training. Yet, much attention has been given to training with very little investigation of recovery. The purpose of this review is to stimulate further research into this vital area of training. Recovery can be categorized in three terms: i) immediate recovery between exertions; ii) short-term recovery between repeats (e.g., between resistance sets or interval bouts); and iii) training recovery between workouts. The focus of this review is training recovery. Full training recovery is essential to optimal performance and improvement. This review includes an examination of extant research on recovery and a very brief review of some potential modalities and techniques for hastening recovery and the time course of recovery and responses to some treatments. Measures of recovery and practical considerations are discussed briefly. Much research is needed in this area, but there are obstacles to high quality research. Attention must be given to key issues in research on recovery, especially the individual response to recovery treatments.  相似文献   

16.
The review discusses the aerobic treatments for farm slurry and food wastes and concentrates in particular on the thermophilic aerobic treatments. Methods are discussed under the heading of chemical, physical and other treatments. From those methods considered, the most suitable physical-microbiological treatment are aerobic thermophilic treatments. The main problem faced in aerobic thermophilic treatments could be the foaming formation during the process, and this could be solved by using different methods, mainly mechanical control method. Aerobic thermophilic treatments are also simple, economical and environmentally accepted. This method is known to have effects, and could be used to assist decontaminations on farms, as such technologies are already used in routine slurry treatment in many farms.  相似文献   

17.
A significant quantum of crude oil is trapped in reservoirs and often unrecoverable by conventional oil recovery methods. Further downstream, the petroleum industry is facing challenges to remove sulfur, metal, nitrogen as well as undesirable organic compounds from the crude.Conventional secondary recovery methods such as water and gas injections helped to increase the productivity of the well, while chemical and physical refinery processes such as hydrodesulfurization, desalting, and high-pressure high-temperature hydrotreating remove most inorganic impurities. The increasing demand for oil in the world coupled with very stringent environmental laws piled economical and technical pressure upon the refinery industry to further improve crude oil recovery as well as reduce sulfur, metal and nitrogen concentration to the low ppm levels.In the search for economical and environmentally friendly solutions, growing attention has been given to biotechnology such as the use of microbial enhanced oil recovery (MEOR). MEOR is an alternate recovery method that uses microorganisms and their metabolic products. In addition, the emerging field of crude oil refining and associated industrial processes such as biodesulfurization, biodemetallation, biodenitrogenation and biotransformation are also covered.This review aims to provide an overview on MEOR and biorefining relevant to the petroleum industry and highlights challenges that need to be overcome to become commercially successful. Literature pertaining to laboratory experiments, field trials and patents are included in view of industrial applications and further developments.  相似文献   

18.
钛的优良特性早已被公认为首选牙用种植材料,其表面氧化膜是形成骨结合的关建。为了进一步增加其耐腐蚀性和生物相容性,人们采取了多种方式进行表面处理,最终达到在植入体的不同部位产生不同的粗糙表面,以利于不同细胞在不同地方的附着,增加其生物活性。同时,达到避免各种污染物对纯钛种植体影响的目的。近年来钛种植体材料表面处理已经成为研究热点,本文就表面处理的方法进行综述。  相似文献   

19.
This is a review of the methods based on counting oligomers in nucleotide and amino acid sequences. Such methods are analogous to the formal linguistic analysis of human texts. This review includes methods based on the calculation of observed occurrences (frequencies) of oligomers and their distribution, as well as those based on deviations between the observed and the expected occurrences (contrast words, genome signatures) in biological sequences. Both types of methods have a wide range of sensitivity and can identify homologous as well as functionally and taxonomically related sequences.  相似文献   

20.
Roles of PPARs in NAFLD: potential therapeutic targets   总被引:1,自引:0,他引:1  
Non-alcoholic fatty liver disease (NAFLD) is a liver pathology with increasing prevalence due to the obesity epidemic. Hence, NAFLD represents a rising threat to public health. Currently, no effective treatments are available to treat NAFLD and its complications such as cirrhosis and liver cancer. Peroxisome proliferator-activated receptors (PPARs) are ligand-activated nuclear receptors which regulate lipid and glucose metabolism as well as inflammation. Here we review recent findings on the pathophysiological role of PPARs in the different stages of NAFLD, from steatosis development to steatohepatitis and fibrosis, as well as the preclinical and clinical evidence for potential therapeutical use of PPAR agonists in the treatment of NAFLD. PPARs play a role in modulating hepatic triglyceride accumulation, a hallmark of the development of NAFLD. Moreover, PPARs may also influence the evolution of reversible steatosis toward irreversible, more advanced lesions. Presently, large controlled trials of long duration are needed to assess the long-term clinical benefits of PPAR agonists in humans. This article is part of a Special Issue entitled Triglyceride Metabolism and Disease.  相似文献   

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