Regeneration

Callus induction from petiole explants has been achieved in Alocasia micholitziana `Green Velvet'. The highest percentage (71%) of explants inducing callus was obtained on MS medium supplemented with 0.5 μM 2,4-D and 0.5 μM kinetin in the dark after 4 months of culture. Shoots were regenerated at the highest frequency of 33.3% under light condition when 0.5 μM BA was added to MS medium with the average of 7.8±2.3 shoots per callus explant. The callus-derived shoots rooted on hormone free MS medium and within 4 weeks the plantlets were ready for acclimatization. The regenerated plants appeared morphologically similar to mother plants.

Observations of wound healing and regeneration of walking legs in specimens of Nymphon australe Hodgson, 1902, Nymphon charcoti Bouvier, 1911, Colssendeis tortipalpus Gordon, 1932 and Pentapycnon charcoti Bouvier 1910 archived in the U. S. National Museum of Natural History collections is reported. One hundred and ninety-four specimens of N. australe were analyzed for evidence of regeneration. Blastema formation and or regenerated limbs of reduced size were found in 64 individuals, 38%. Forty-four specimens of N. charcoti were analyzed for evidence of regeneration. A blastema and/or regenerated limbs of reduced size were found in 12 individuals, 27%. Fifteen specimens of Colssendeis tortipalpus were analyzed for evidence of regeneration. Five individuals, 33%, had either a fully regenerated walking leg of reduced size or a blastema was present. Ten individuals of Pentapycnon charcoti were analyzed for evidence of regeneration. None of these animals showed signs of regeneration. The ...

For centuries, inflammatory/foreign body reactions have plagued the attempts of clinicians to use metals for tissue and bone reconstructions. Since corrosion contributes to the rejection of metal by the body, an extremely bioinert metal - tantalum - has been successfully used in medicine. The outstanding biocompatibility and flexibility of tantalum established the basis for a growing cadre of clinical applications. One important application which benefited from the introduction of powder (particle) metallurgy is use of tantalum as bone implants. Porous materials have re-shaped the landscape of bone implants, as they allow for bone ingrowth and biological fixation, and eliminate implant loosening and related treatment failures. The unique bone-mimicking properties of porous tantalum enabled the use of tantalum as a material for bulk implants, and not only for coatings, as is the case with other porous metals. Moreover, porous tantalum also facilitates the ingrowth of soft tissue, inc...

The past decade has witnessed an upsurge in studies demonstrating mitochondrial transfer as one of the emerging mechanisms through which mesenchymal stem cells (MSCs) can regenerate and repair damaged cells or tissues. It has been found to play a critical role in healing several diseases related to brain injury, cardiac myopathies, muscle sepsis, lung disorders and acute respiratory disorders. Several studies have shown that various mechanisms are involved in mitochondrial transfer that includes tunnel tube formation, micro vesicle formation, gap junctions, cell fusion and others modes of transfer. Few studies have investigated the mechanisms that contribute to mitochondrial transfer, primarily comprising of signaling pathways involved in tunnel tube formation that facilitates tunnel tube formation for movement of mitochondria from one cell to another. Various stress signals such as release of damaged mitochondria, mtDNA and mitochondrial products along with elevated reactive oxygen...

Regenerative processes occurring under physiological (maintenance) and pathological (reparative) conditions are a fundamental part of life and vary greatly among different species, individuals, and tissues. Physiological regeneration occurs naturally as a consequence of normal cell erosion, or as an inevitable outcome of any biological process aiming at the restoration of homeostasis. Reparative regeneration occurs as a consequence of tissue damage. Although the central nervous system (CNS) has been considered for years as a “perennial” tissue, it has recently become clear that both physiological and reparative regeneration occur also within the CNS to sustain tissue homeostasis and repair. Proliferation and differentiation of neural stem/progenitor cells (NPCs) residing within the healthy CNS, or surviving injury, are considered crucial in sustaining these processes. Thus a large number of experimental stem cell-based transplantation systems for CNS repair have recently been establ...

Over the past few years, substantial progress has been made in the field of stem cell regeneration of the intervertebral disc. Autogenic mesenchymal stem cells in animal models can arrest intervertebral disc degeneration or even partially regenerate it and the effect is suggested to be dependent on the severity of degeneration. Mesenchymal stem cells (MSCs) are able to escape alloantigen recognition which is an advantage for allogenic transplantation. A number of injectable scaffolds have been described and various methods to pre-modulate MSCs’ activity have been tested. In future, work will need to address the use of mesenchymal stem cells in large animal models and the fate of the implanted mesenchymal stem cells, particularly in the long term, in animals. This review examines the state-of-the-art in the field of stem cell regeneration of the intervertebral disc, and critically discusses, with scientific support, the issues involved, before stem cells could be used in human subjects.

The ubiquitin proteasome system (UPS) is the main proteolytic system of cells. Recent evidence suggests that the UPS plays a regulatory role in regeneration processes. Here, we explore the possibility that the UPS is involved during intestinal regeneration of the sea cucumber Holothuria glaberrima. These organisms can regenerate most of their digestive tract following a process of evisceration. Initially, we identified components of H. glaberrima UPS, including sequences for Rpn10, β3, and ubiquitin-RPL40. Predicted proteins from the mRNA sequences showed high degree of conservation that ranged from 60% (Rpn10) to 98% (Ub-RPL40). Microarrays and RT-PCR experiments showed that these genes were upregulated during intestinal regeneration. In addition, we demonstrated expression of alpha 20S proteasome subunits and ubiquitinated proteins during intestinal regeneration and detected them in the epithelium and connective tissue of the regenerating intestine. Finally, the intestinal regener...

Epigenetic modifiers are an emerging class of anti-tumor drugs, potent in multiple cancer contexts. Their effect on spontaneously developing autoimmune diseases has been little explored. We report that a short treatment with I-BET151, a small-molecule inhibitor of a family of bromodomain-containing transcriptional regulators, irreversibly suppressed development of type-1 diabetes in NOD mice. The inhibitor could prevent or clear insulitis, but had minimal influence on the transcriptomes of infiltrating and circulating T cells. Rather, it induced pancreatic macrophages to adopt an anti-inflammatory phenotype, impacting the NF-κB pathway in particular. I-BET151 also elicited regeneration of islet β-cells, inducing proliferation and expression of genes encoding transcription factors key to β-cell differentiation/function. The effect on β cells did not require T cell infiltration of the islets. Thus, treatment with I-BET151 achieves a 'combination therapy' currently advocated by...

Heathlands are areas which contain poor soils in which trees were removed and burning and grazing prevented their regrowth. (English Nature, 2002) There are many types of the heathland habitat, but the area of the study was The New Forest National Park which is characterised as a lowland heathland. Lowland heathlands are heathlands found in land lower than 300 metres but the types of heathlands within it can be just as varied as the upland heathlands. To maintain heathlands, it is important to arrest its climax in its succession of pine and birch woodlands otherwise it can be lost, this can be done in many ways but the most prolific way it is done is by cutting and burning. The management is done in regular cycles in the separate heathland areas to ensure that the heathland stays in its building and mature stages of succession and doesn’t enter the degenerate or dying phase.

The New Forest National Park in Hampshire, England claims that it contains the best maintained heathland in Europe, so this seemed a good reason to undertake a geographical study in the area. The study site of the dissertation was an area east of the town Lyndhurst within Bolton’s Bench and the White Moor. Quadrats were placed in areas which had been managed separately by both cutting and burning and ranged from being managed from 2004/05 until 2014/15 to investigate whether the species richness or biodiversity had improved in the managed areas the longer the site was left. The study also tested for the populations of Gorse (Ulex spp,) in each individual site to test whether or not management reduced its dominance on the heathland, as gorse can take over heathlands if not managed.  The study also was testing which method of management was more effective in the management of the heathland. The study used the Simpsons diversity index for identifying the species richness in each site of management which was done by taxonomy during the fieldwork by counting the number and type of species in each site. 

What was found is that the technique of burning seemed to be the most effective method of management in both the heathland in general and in reducing the numbers of gorse found within an area. Cutting seemed to be occurring in the outside of the heathland to remove other species such as hard fern and brambles as they can also be trouble for heathland health however it was plain to see it wasn’t actually being used to benefit the heathland plants itself.  Burning also tended to open up completely new bare ground so secondary succession was easy to occur.  To test this and get more data, more time would have been needed over several years to observe these areas more deeply to see the change in species richness.