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Many diseases and/or physical defects due to injury result in the loss of specialized cells within organ systems and lead to organ system dysfunction. The ultimate goal of cell-based therapies is to regenerate and restore normal function. Populations of embryonic, fetal, adult stem cells and inducible pluripotent stem cells generated by reprogramming of adult cells show promise for the treatment of a variety of diseases. In addition, the recent advancements in adult stem cell biology in both normal and pathological conditions have led to the identification of some intrinsic and extrinsic factors that govern the decision between self renewal versus differentiation of tissue-resident adult stem cells. This is of primary importance for the design of an approach of stem cell-based therapy focused on their in vivo modulation by conventional chemical and biological therapeutics capable to stimulate endogenous cell regeneration. Such therapeutics can act in vivo to promote cell survival, proliferation, differentiation, reprogramming and homing of stem cells or can modulate their niches. In this review, we will highlight the burst of recent literature on novel perspectives of regenerative medicine and their possible clinical applications.

A 24‐hour‐old Welsh‐Thoroughbred foal presented for routine surgical repair of an abdominal and body wall hernia. The colt became acutely colicky and emergency celiotomy was performed revealing abnormal anatomical configuration of the gastrointestinal tract (GIT). Incomplete gastrointestinal rotation is a rare congenital anomaly only described in man. This report describes the clinical and diagnostic findings, surgical and medical treatment, and outcome of a neonatal foal with nonrotation of the GIT.

Mammary tumours are uncommon in mares. Sarcomas of the breast account for less than 1% of all human primary malignancies and, among these types of tumours, malignant fibrous histiocytoma (MFH) is very rare. This report describes a 6‐year‐old uniparous Paint mare that was presented for investigation of right mammary gland enlargement of 3 weeks' duration. The clinical and histopathological findings in this mare with malignant fibrous histiocytoma of the mammary gland as well as complications of bilateral mastectomy are detailed. At one year follow‐up there were no clinical signs of recurrence.

This report describes the diagnosis and treatment of vulvar papillomatosis with carcinoma in situ in a 25‐year‐old mare. Papillomavirus was demonstrated via immunohistochemical staining of biopsies of the lesion. The papillomas were removed via laser excision and the surrounding vulvar tissue injected with 5‐fluorouracil. Additional more extensive laser excisions were required due to recurrence.

The myosin heavy chain (MHC) composition of a given muscle determines the contractile properties and, therefore, the fiber type distribution of the muscle. MHC isoform expression in the laryngeal muscle is modulated by neural input and function, and it represents the cellular level changes that occur with denervation and reinnervation of skeletal muscle. The objective of this study was to evaluate the pattern of MHC isoform expression in laryngeal muscle harvested from normal cadavers and cadavers with naturally occurring left laryngeal hemiplegia secondary to recurrent laryngeal neuropathy. Left and right thyroarytenoideus (TA) and cricoarytenoideus dorsalis (CAD) were obtained from 7 horses affected with left-sided intrinsic laryngeal muscle atrophy and from 2 normal horses. Frozen sections were evaluated histologically for degree of atrophy and fiber type composition. MHC isoform expression was determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of muscle protein. Histologic atrophy was seen in all atrophic muscles and some right-sided muscles of 3 affected horses, as well as the left TA of 1 normal horse. Fiber type grouping or loss of type I muscle fibers was observed in the left-sided laryngeal muscles in all but 1 affected horse, as well as in the right muscles of 2 affected horses, and the left TA of 1 normal horse. SDS-PAGE showed 2 bands corresponding to the type I and type IIB myosin isoforms in the CAD and TA of the 2 normal horses. Affected horses demonstrated a trend toward increased expression of the type IIB isoform and decreased expression of the type I isoform in atrophic muscles. This study confirmed the presence of histologic abnormalities in grossly normal equine laryngeal muscle, and it demonstrated an increased expression of type IIB MHC with a concurrent decreased expression of type I MHC in affected muscles. Evaluation of muscle fiber changes at the cellular level under denervated and reinnervated conditions may aid in assessing future strategies for reinnervation or regeneration of atrophic laryngeal muscle.

The accuracy problem of the semi-analytical method for shape design sensitivity analysis has been reported for linear and non-linear structures. The source of error is the numerical differentiation of the element internal force vector, which is inherent to the semi-analytical approach. Such errors occur for structures whose displacement field is characterized by large rigid body rotations of individual elements. This paper presents a method for the improvement of semi-analytical sensitivities. The method is based on the element free body equilibrium conditions, and on the exact differentiation of the rigid body modes. The method is efficient, simple to code, and can be applied to linear and non-linear structures. The numerical examples show that this approach eliminates the abnormal errors that occur in the conventional semi-analytical method. Copyright © 2001 John Wiley & Sons, Ltd.

Abstract: Bacteriocins produced by lactic acid bacteria are a heterogeneous group of peptide inhibitors which include lantibiotics (class I, e.g. nisin), small heat-stable peptides (class II, e.g. pediocin AcH/PA1) and large heat-labile proteins (class III, e.g. helveticin J). Many bacteriocins belonging to the first two groups can be successfully used to inhibit undesirable microorganisms in foods, but only nisin is produced industrially and is licensed for use as a food preservative in a partially purified form. This review focuses on the production and purification of class I and class II bacteriocins from lactic acid bacteria. Bacteriocin production is growth associated but the yield of bacteriocin per unit biomass is affected by several factors, including the producing strain, media (carbohydrate and nitrogen sources, cations, etc.) and fermentation conditions (pH, temperature, agitation, aeration and dilution rate in continuous fermentations). Continuous fermentation processes with cell recycle or immobilized cells can result in a dramatic improvement in productivity over batch fermentations. Several simple recovery processes, based on adsorbing bacteriocin on resins or silica compounds, have been developed and can be used to build integrated production processes.

The influence of pH?on growth, and lactic acid and bacteriocin production by Lactococcus lactis subsp. lactis 140 NWC was studied during batch fermentation in a lactose-based complex medium. Growth and lactic acid production were modelled using a simple logistic equation while substrate consumption was found to be a function of growth and lactic acid production rate. The optimal pH?for growth and lactic acid production was between 6.0 and 6.5. Bacteriocin production showed primary metabolite kinetics. pH?had a dramatic effect on the production of the bacteriocin, lactococcin 140. A maximum activity of 15.4×10 6 AU (arbitrary units) l –1 was obtained after 7 h at pH?5.5. Maximum bacteriocin activity was achieved before the end of growth and was followed by a decrease in activity, which was due to adsorption to the cells of the producing organism, possibly followed by degradation by specific proteases. Both bacteriocin production and degradation rates were higher at pH?5.0 and 5.5, resulting in sharper activity peaks than at pH?6.0 or 6.5. On the basis of the experimental results a qualitative model for bacteriocin production is proposed.

Fumaric acid production by Rhizopus arrhizus from potato flour was studied at different initial substrate concentrations (S), C/N ratios and fermentation times (tf) in a composite design experiment. By using response surface methodology and canonical analysis, the experimental values of fumaric acid and mycelial biomass yields and productivity were fitted to the only statistically significant factors with mean percentage errors of 11, 26 and 13%, respectively. Owing to the limited statistical significance of the C/N ratio, it was possible to determine the values of S (25–50 g/l of glucose equivalent) and tf(44–100 h) associated with fumaric acid yields ranging from 60 to 75% and productivities varying from 6 to 8.4 g/l per day. Since such results were in quite good agreement with previous experiments carried out on other starchy materials, the above operating conditions might be used to minimize fumaric acid production costs as a function of the feed-stock used.

A new procedure is described for the assay of nisin in milk by using capillary zonal electrophoresis. Since nisin assay in milk and in other matrices is hampered by its adsorption to both the protein and lipid milk fractions, a simple extraction procedure was devised to remove caseins and lipids, which interfere with nisin detection. An excellent linear response to nisin concentration was observed in the range from 10 to 100 μg/ml with a mean coefficient of variation of 3.8%. © Rapid Science Ltd. 1998 [ABSTRACT FROM AUTHOR]