Forensic applications.

The introduction of DNA based identity testing has revolutionized the field of forensic analysis of biological materials. Most of the publications during the past year expand earlier studies that began more than seven years ago, on the properties of DNA recovered from different types of evidential materials; these studies examine the suitability of these samples for identity testing, the effect of different environmental insults the population genetics of loci used for identity testing, and the methods used for statistical analysis of the DNA patterns.     

Foam fractionation applications

Biotechnological downstream processing faces several challenges, such as dilute product streams and contained target products which are sensitive to heat, oxidation, other chemicals, etc. State-of-the-art separation methods, e.g. chromatography, are not always the best option due to variable yield losses and high costs. Foam fractionation appears as a promising alternative unit operation in biotechnological downstream processing. From its applications in metal industry and on fish farms, it was developed further towards the recovery of phytonutrients, metabolites and proteins. However, no large scale applications of foam fractionation in biotechnological downstream processing exist yet. This is due to the complexity of various biotechnological media, which makes a universalized approach for systematic process design of protein separations difficult. Ongoing research in the fields of process engineering, surface chemistry and protein chemistry can help to close this gap. Although many different substances, such as detergents, have been separated or recovered using foam fractionation, this review focuses mainly on biotechnological applications, more specifically on protein separation.     

Industrial enzyme applications

The effective catalytic properties of enzymes have already promoted their introduction into several industrial products and processes. Recent developments in biotechnology, particularly in areas such as protein engineering and directed evolution, have provided important tools for the efficient development of new enzymes. This has resulted in the development of enzymes with improved properties for established technical applications and in the production of new enzymes tailor-made for entirely new areas of application where enzymes have not previously been used.     

Biological applications of dendrimers

In the past year, significant advances have been made in the synthesis and study of glycodendrimers and peptide dendrimers. Application of these dendrimers to the study of carbohydrate-protein and protein-protein interactions has facilitated the understanding of these processes. In addition, dendrimers show great promise as DNA- and drug-delivery systems.     

Corrosion in bioprocessing applications

Corrosion in bioprocessing applications is described for a 25-year-old bioprocessing pilot plant facility. Various available stainless steel alloys differ greatly in properties owing to the impact of specific alloying elements and their concentrations. The alloy property evaluated was corrosion resistance as a function of composition under typical bioprocessing conditions such as sterilization, fermentation, and cleaning. Several non-uniform forms of corrosion relevant to bioprocessing applications (e.g., pitting, crevice corrosion, intergranular attack) were investigated for their typical causes and effects, as well as alloy susceptibility. Next, the corrosion resistance of various alloys to specific bioprocessing-relevant sources of corrosion (e.g., medium components, acids/bases used for pH adjustment, organic acid by-products) was evaluated, along with the impact of temperature on corrosion progression. Best practices to minimize corrosion included considerations for fabrication (e.g., welding, heat treatments) and operational (e.g., sterilization, media component selection, cleaning) approaches. Assessments and repair strategies for observed corrosion events were developed and implemented, resulting in improved vessel and overall facility longevity.     

Metrology for ultrasonic applications

This paper provides a review of current metrological capability applied to the characterisation of the acoustic output of equipment used within medical ultrasonic applications. Key measurement devices, developed to underpin metrology in this area, are the radiation force balance, used to determine total output power, and the piezo-electric hydrophone, used to resolve the spatial and temporal distribution of acoustic pressure. The measurement infrastructure in place within the United Kingdom ensuring users are able to carry out traceable measurements of these quantities in a meaningful way, is described. This includes the relevant primary standards, the way international equivalence of national standards is demonstrated and the routes by which the standards are disseminated to the user community. Emerging measurement techniques that may in future lead to improved measurement capability, are also briefly discussed.     

Biomedical applications of nisin

Nisin is a bacteriocin produced by a group of Gram‐positive bacteria that belongs to Lactococcus and Streptococcus species. Nisin is classified as a Type A (I) lantibiotic that is synthesized from mRNA and the translated peptide contains several unusual amino acids due to post‐translational modifications. Over the past few decades, nisin has been used widely as a food biopreservative. Since then, many natural and genetically modified variants of nisin have been identified and studied for their unique antimicrobial properties. Nisin is FDA approved and generally regarded as a safe peptide with recognized potential for clinical use. Over the past two decades the application of nisin has been extended to biomedical fields. Studies have reported that nisin can prevent the growth of drug‐resistant bacterial strains, such as methicillin‐resistant Staphylococcus aureus, Streptococcus pneumoniae, Enterococci and Clostridium difficile. Nisin has now been shown to have antimicrobial activity against both Gram‐positive and Gram‐negative disease‐associated pathogens. Nisin has been reported to have anti‐biofilm properties and can work synergistically in combination with conventional therapeutic drugs. In addition, like host‐defence peptides, nisin may activate the adaptive immune response and have an immunomodulatory role. Increasing evidence indicates that nisin can influence the growth of tumours and exhibit selective cytotoxicity towards cancer cells. Collectively, the application of nisin has advanced beyond its role as a food biopreservative. Thus, this review will describe and compare studies on nisin and provide insight into its future biomedical applications.     

纳米酶的抗菌作用及其机制研究进展

抗生素类药物的发现和使用给人类提供了抗击细菌感染的强大武器。但是,抗生素长期使用导致的细菌耐药问题限制了其在临床上的应用。开发新型的基于纳米酶(Nano-Enzyme)的新型抗菌剂为解决上述问题提供了新思路。将纳米酶可以归为两大类:一类是酶和纳米材料的复合材料;另一类是纳米材料本身具有类酶活性。因为银(Ag)纳米粒子是历史最悠久且研究最广泛的纳米抗菌剂,而且其抗菌机制多样化,因此将Ag纳米粒子的抗菌机制和最新进展单独论述。纳米抗菌剂可以组合多种抗菌机制协同抗菌,从而提高其抗菌性能。因此,在这篇综述中系统介绍了Ag纳米粒子和上述2种类型纳米抗菌剂的最新研究进展和抗菌机制,重点介绍了纳米材料的物理性质对抗菌活性和生物安全性的影响。最后,该综述还强调了该领域目前面临的问题和挑战,并对该领域的发展前景进行了展望。     

Pharmaceutical applications of peptidomimetics

Summary Nature has used a library approach to constructing ligands for specific receptors and enzymes by combining a limited functional diversity of 20 amino acid side chains with a small array of secondary structure motifs — reverse turns, -helices and -strands. The dissection of multidomain proteins into small synthetic conformationally restricted components is an important step in the design of low-molecular-weight nonpeptides that mimic the activity of the native protein. Mimetics of critical functional domains might possess beneficial properties with regard to specificity and therapeutic potential compared to the intact proteinaceous species. Combinatorial secondary-structure-templated libraries provide a powerful engine for the development of novel vaccines and pharmaceuticals.This paper is based on a presentation given at the Symposium on Peptide structure and Design as part of the 31st Annual ACS Western Regional Meeting held in San Diego, CA, USA, October 18–21, 1995.     

Therapeutic applications of ultrasound

Therapeutic applications of ultrasound predate its use in imaging. A range of biological effects can be induced by ultrasound, depending on the exposure levels used. At low levels, beneficial, reversible cellular effects may be produced, whereas at high intensities instantaneous cell death is sought. Therapy ultrasound can therefore be broadly divided into “low power” and “high power” applications. The “low power” group includes physiotherapy, fracture repair, sonophoresis, sonoporation and gene therapy, whereas the most common use of “high power” ultrasound in medicine is probably now high intensity focused ultrasound. Therapeutic effect through the intensity spectrum is obtained by both thermal and non-thermal interaction mechanisms. At low intensities, acoustic streaming is likely to be significant, but at higher levels, heating and acoustic cavitation will predominate. While useful therapeutic effects are now being demonstrated clinically, the mechanisms by which they occur are often not well understood.     

EST及其应用

随着HGP（HumanGenomeProject）的实施,人类基因组测序进展顺利,并有望于2003年提前完成。后基因组计划的重点之一在于基因组表达概况和功能的研究。EST（expressedsequencetags）是一组短的cDNA部分序列,是由大量随机取出的cDNA克隆一次测序得到的组织或细胞基因组的表达序列标签。其在基因组研究中的应用已相当广泛并具有良好的前景。该文就EST的产生、相关数据库和应用情况作一综述。     

Bet-hedging applications for conservation

One of the early tenets of conservation biology is that population viability is enhanced by maintaining multiple populations of a species. The strength of this tenet is justified by principles of bet-hedging. Management strategies that reduce variance in population size will also reduce risk of extinction. Asynchrony in population fluctuations in independent populations reduces variance in the aggregate of populations whereas environmental correlation among areas increases the risk that all populations will go extinct. We review the theoretical rationale of bet-hedging and suggest applications for conservation management of least terns in Nebraska and grizzly bears in the northern Rocky Mountains of the United States. The risk of extinction for least terns will be reduced if we can sustain the small central Platte River population in addition to the larger population on the lower Platte. Similarly, by restoring grizzly bears to the Bitterroot wilderness of Idaho and Montana can reduce the probability of extinction for grizzly bears in the Rocky Mountains of the United States by as much as 69–93%.     

Biochemiluminescence and biomedical applications

Although used for analytical purposes for more than 40 years it is only recently that biochemiluminescence (BCL) has found widespread acceptance. Methods employing BCL reactions now play an important role in biomedical research and laboratory medicine. The main attractions for the assay technology include exquisite sensitivity (attomole-zeptomole), high selectivity, speed and simplicity. In biomedical research, the most important applications of BCL are: (1) to estimate microbial numbers and to assess cellular states (e.g., after exposure to antibiotic or cytotoxic agents) and in reporter gene studies (firefly luciferase gene); (2) NAD(P)H involved in redox/dehydrogenase studies usingVibrio luciferase complex; (3) BCL labels and CL detection of enzyme labels in immunoassays are the most widespread routine application for this technology. BCL enzyme immunoassays represent the most active area of development, e.g., enhanced BCL method for peroxidase and BCL assays for alkaline phosphatase labels using adamantyl 1,2-dioxetane.Abbreviations BCL biochemiluminescence - CL chemiluminescence - RLU relative light unit - ROS reactive oxygen species     

Medicinal applications of fullerenes

Fullerenes have attracted considerable attention in different fields of science since their discovery in 1985. Investigations of physical, chemical and biological properties of fullerenes have yielded promising information. It is inferred that size, hydrophobicity, three-dimensionality and electronic configurations make them an appealing subject in medicinal chemistry. Their unique carbon cage structure coupled with immense scope for derivatization make them a potential therapeutic agent. The study of biological applications has attracted increasing attention despite the low solubility of carbon spheres in physiological media. The fullerene family, and especially C60, has appealing photo, electrochemical and physical properties, which can be exploited in various medical fields. Fullerene is able to fit inside the hydrophobic cavity of HIV proteases, inhibiting the access of substrates to the catalytic site of enzyme. It can be used as radical scavenger and antioxidant. At the same time, if exposed to light, fullerene can produce singlet oxygen in high quantum yields. This action, together with direct electron transfer from excited state of fullerene and DNA bases, can be used to cleave DNA. In addition, fullerenes have been used as a carrier for gene and drug delivery systems. Also they are used for serum protein profiling as MELDI material for biomarker discovery. In this review we report the aspects of medicinal applications of fullerenes.     

Analytical applications of aptamers

So far, several bio-analytical methods have used nucleic acid probes to detect specific sequences in RNA or DNA targets through hybridisation. More recently, specific nucleic acids, aptamers, selected from random sequence pools, have been shown to bind non-nucleic acid targets, such as small molecules or proteins. The development of in vitro selection and amplification techniques has allowed the identification of specific aptamers, which bind to the target molecules with high affinity. Many small organic molecules with molecular weights from 100 to 10,000 Da have been shown to be good targets for selection. Moreover, aptamers can be selected against difficult target haptens, such as toxins or prions. The selected aptamers can bind to their targets with high affinity and even discriminate between closely related targets.

Aptamers can thus be considered as a valid alternative to antibodies or other bio-mimetic receptors, for the development of biosensors and other analytical methods. The production of aptamers is commonly performed by the SELEX (systematic evolution of ligands by exponential enrichment) process, which, starting from large libraries of oligonucleotides, allows the isolation of large amounts of functional nucleic acids by an iterative process of in vitro selection and subsequent amplification through polymerase chain reaction.

Aptamers are suitable for applications based on molecular recognition as analytical, diagnostic and therapeutic tools. In this review, the main analytical methods, which have been developed using aptamers, will be discussed together with an overview on the aptamer selection process.