"Rediscovery" of a forgotten organelle, the primary cilium: the root cause of a plethora of disorders

The primary cilium was recognised in the late 19th century. Conclusive evidence of its existence required the advent of the electron microscope (1950s-1960s), after which its comparison with motile cilia of the (9 + 2) variety was made by Sorokin. Although a small group of devotees researched the primary cilium from this period until the late 1990s, its function as a sensor (previously advocated by Tony Poole) was established because it produced Ca2+ transients in intracellular signalling. The pathobiological consequences of ciliary agenesis or dysfunction was emphasised in the mid 1990s. But it was only after the recognition that agenesis could be due to mutations in intraflagellar transport proteins several years later that the pathological sequelae were appreciated. Since the early 2000s, the primary cilium has now been implicated as having many functions in cellular behaviour and development, such that disorder in this almost ubiquitous organelle in many tissues of the body leads to an astonishingly wide range of symptoms, from polycystic kidney disease to Alzheimer's. This organelle, dismissed as vestigial or rudimentary by most cell biologists for well over a century, can no longer be ignored in almost any medical and development condition. There is also very much more to learn about the biology of this fascinating organelle.Biomedical Reviews 2013; 24: 1-7

A new journal – "Theoretical Biology and Medical Modelling"

Biology has a conceptual basis that allows one to build models and theorize across many life sciences, including medicine and medically-related disciplines. A dearth of good venues for publication has been perceived during a period when bioinformatics, systems analysis and biomathematics are burgeoning. Steps have been taken to provide the sort of journal with a quick turnaround time for manuscripts which is online and freely accessible to all readers, whatever their persuasion or discipline. We have now been running for some time a journal which has had many good papers presented pre-launch, and a steady stream of papers thereafter. The value of this journal as a new venue has already been vindicated. Within a short space of time, we have founded a state-of-the-art electronic journal freely accessible to all in a much sort-after interdisciplinary field that will be of benefit to the thinking life scientist, which must include medically qualified doctors as well as scientists who prefer to build their new hypotheses on basic principles and sound concepts underpinning biology. At the same time, these principles are not sacrosanct and require critical analysis. The journal promises to deliver many exciting ideas in the future

Transporting cells over several days without dry-ice

This paper describes a simple, hazard-free and inexpensive procedure that allows researchers to send cultured cells across the globe at ambient temperatures. The method enables transit of up to 2 weeks without compromising cell recovery. Its use will assist collaborators in distant laboratories to exchange cells without using dry-ice

Action of Lovastatin (Mevinolin) on an in vitro model of angiogenesis and its co-culture with malignant melanoma cell lines

BACKGROUND: Lovastatin and other statins may reduce the development of melanomas. The effects on melanoma cells and their ability to enhance angiogenesis in a co-culture system presented an opportunity to assess whether Lovastatin act on melanoma cells, HUVEC or both types of cells. RESULTS: Direct effects of co-culturing two different malignant melanoma cells (A375 and G361) on the process of angiogenesis in vitro was studied with our angiogenesis model[1], based on human dermal fibroblasts and human umbilical vein endothelial cells (HUVEC). Co-cultures were set up using "sland" and "dispersed seeding" techniques. A statistically significant increase in tubule formation in both cases was observed compared to controls. The effects of doses equivalent to therapeutic concentrations of Lovastatin were analysed. The drug inhibited the growth of all cell types, induced apoptosis, and markedly reduced the formation of tubules in the angiogenesis model at low concentrations. Its action was successfully reversed by the introduction of geranylgeranyl pyrophosphate. CONCLUSION: Lovastatin can reduce both tumour (melanoma) cell growth, and the angiogenic activity of these cells in co-cultures using an established 2-dimensional model angiogenesis system beyond that which would be seen by reduced proliferation alone

Possible attenuation of the G2 DNA damage cell cycle checkpoint in HeLa cells by extremely low frequency (ELF) electromagnetic fields

BACKGROUND: The issue remains unresolved as to whether low frequency magnetic fields can affect cell behaviour, with the possibility that they may be in part responsible for the increased incidence of leukaemia in parts of the population exposed to them. METHODS: Combined treatment of HeLa cells with gamma-irradiation (1, 3 and 5 Grays) and extra low frequency magnetic fields of ~50 Hz was carried out under rigorously controlled conditions. RESULTS: Synchronised cells progressing from S-phase arrived at mitosis on average marginally ahead of irradiation controls not exposed to ELF. In no instance out of a total of twenty separate experiments did this "double-insult" further delay entry of cells into mitosis, as had been anticipated. CONCLUSION: This apparently "non-genotoxic" agent (ELF) appears to be capable of affecting cells that would normally arrest for longer in G2, suggesting a weakening of the stringency of the late cycle (G2) checkpoint

Metabolic scaling: consensus or controversy?

BACKGROUND: The relationship between body mass (M) and standard metabolic rate (B) among living organisms remains controversial, though it is widely accepted that in many cases B is approximately proportional to the three-quarters power of M. RESULTS: The biological significance of the straight-line plots obtained over wide ranges of species when B is plotted against log M remains a matter of debate. In this article we review the values ascribed to the gradients of such graphs (typically 0.75, according to the majority view), and we assess various attempts to explain the allometric power-law phenomenon, placing emphasis on the most recent publications. CONCLUSION: Although many of the models that have been advanced have significant attractions, none can be accepted without serious reservations, and the possibility that no one model can fit all cases has to be more seriously entertained

Purification and characterisation of cell survival factor 1 (TCSF1) from Tetrahymena thermophila

Of a number of peptides isolated from the extracellular medium of Tetrahymena cultures, two with masses 9.9 and 22.4 kDa allowed low-density cultures of this ciliate to survive and enter a proliferate phase. The smaller peptide (TCSF1) also greatly helped cultured mammalian fibroblasts to survive in medium containing very low concentrations of serum for considerably longer than controls, and to grow when full strength medium was restored. The primary sequence of the TCSF1 was determined, and synthetic TCSF1 was observed to exhibit rescuing activity comparable to that of the native peptide

Reflections on the responsible conduct of cancer research

Most cancer researchers regularly practice the responsible conduct of research (RCR) without consciously considering it. As professional scientists, we simply do what we are trained to do. However, as we train a new generation of cancer researchers in our laboratories, we must be vigilant against undue complacency. In an age when misconduct in research is receiving more media attention than ever before, we should periodically take a moment of pause and reflect upon the meaning and practice of responsibly conducting research. Rather than meeting minimum standards in a compliance-driven manner, we should practice forethought and periodically consider how we can improve. We, as leaders in cancer research, must then push our peers to do the same. By embedding RCR into the culture of cancer research through a multilayer approach, including regular assessment at the levels of individual research groups, departmentally, and institutionally, we will become a model discipline in the responsible conduct of research

Recovery of the Decorin-Enriched Fraction, Extract (D), From Human Skin: An Accelerated Protocol

The original extraction procedure of Engel and Catchpole [1] has often been used to recover decorin-enriched material from the skin. This material has a strong inhibitory effect on fibroblast proliferation, and clearly suppresses it in skin except after the first 5–6 days of wounding when new scaffold material is required. The aim of our present study has been to find and evaluate the product of a faster recovery method, and to check its consistency as a more reliable means of regularly obtaining sufficient material for topical application in wounds that might become hypertrophic. Modifications of the original Toole and Lowther [2] extraction procedure have been carefully evaluated in an attempt to cut preparation time without compromising biological activity of the inhibitory extract. We have devised a faster recovery procedure without compromising biological activity, even if initial recovery has been somewhat reduced. The latter problem could be offset by repeated cycles of the final extraction step. The main inhibitory activity is shown to be within the decorin-enriched “extract D,” as the core protein and DSPG II. Adjustment of the extract towards neutrality after dialysis against water keeps most of the extracted protein in solution and yielded a decorin-enriched preparation that had a specific activity equivalent to that of the old method. It also yielded a fraction that was readily lyophilised to give a small amount of material that could be stored indefinitely without loss of activity and readily redissolved in aqueous solution. A reliable and relatively quick method is presented for the production, from human skin, of a decorin-enriched preparation that has strong fibroblast inhibitory action. The value of the procedure is that it is inexpensive and can produce the quantities that might be used topically in reducing hypertrophic scarring of wounds

Pegylated derivatives of recombinant human arginase (rhArg1) for sustained in vivo activity in cancer therapy: preparation, characterization and analysis of their pharmacodynamics in vivo and in vitro and action upon hepatocellular carcinoma cell (HCC)

<p>Abstract</p> <p>Background</p> <p>Protein used in medicine, e.g. interferon, are immunogenic and quickly broken down by the body. Pegylation is a recognized way of preserving their integrity and reducing immune reactions, and works well with enzymes used to degrade amino acids, a recent focus of attention in controlling cancer growth. Of the two arginine-degrading enzymes being explored clinically, arginine deiminase is a decidedly foreign mycoplasm-derived enzyme, whereas human arginase 1 is a native liver enzyme. Both have been pegylated, the former with adjuncts of 20 kD, the latter with 5 kD PEG. Pegylation is done by several different methods, not all of which are satisfactory or desirable.</p> <p>Methods</p> <p>The preparation of novel polyethylene glycol (PEG) derivatives for modifying proteins is described, but directed specifically at pegylation of recombinant human arginase 1 (rhArg1). rhArg1 expressed in <it>Escherichia coli </it>was purified and coupled in various ways with 5 different PEG molecules to compare their protective properties and the residual enzyme activity, using hepatocellular cell lines both in vitro and in vivo.</p> <p>Results</p> <p>Methoxypolyethylene glycol-succinimidyl propionate (mPEG-SPA 5,000) coupled with very high affinity under mild conditions. The resulting pegylated enzyme (rhArg1-peg_{5,000 mw}) had up to 6 PEG chains of 5K length which not only protected it from degradation and any residual immunogenicity, but most importantly let it retain >90% of its native catalytic activity. It remained efficacious in depleting arginine in rats after a single ip injection of 1,500 U of the conjugate as the native enzyme, plasma arginine falling to >0.05 μM from ~170 μM within 20 min and lasting 6 days. The conjugate had almost the same efficacy as unpegylated rhArg1 on 2 cultured human liver cancer (HCC) cell lines. It was considerably more effective than 4 other pegylated conjugates prepared.</p> <p>Conclusion</p> <p>Valuable data on the optimization of the pegylation procedure and choice of ligand that best stabilizes the enzyme arginase 1 are presented, a protocol that should equally fit many other enzymes and proteins. It is a long lasting arginine-depleting enzyme in vivo which will greatly improve its use in anti-cancer therapy.</p