Remyelination — An effective means of neuroprotection

Remyelination following central nervous system (CNS) demyelination restores rapid saltatory conduction of action potentials and contributes to the maintenance of axonal integrity. This robust regenerative phenomenon stands in contrast to the limited repair capacity that is characteristic of CNS neuronal injury. However, despite its efficiency in experimental models and some clinical diseases, remyelination failure becomes an increasingly pronounced feature of the pathology of chronic multiple sclerosis (MS) lesions. Chronic demyelination predisposes axons to atrophy, an irreversible event that is a major pathological correlate of progressive functional decline. This has created a compelling case for developing therapies that promote remyelination: evidence from experimental animal models suggests that hormones may have a beneficial role to play in this regard.     

The prevention of the fluid-electrolyte "problem" by simple means

Proper fluid balance may be maintained in patients after operation by the employment of simple, inexpensive procedures which may be carried out even in the smallest hospitals. Daily weighing of patients, measurement of fluid intake and output, and knowledge of the probable electrolyte content of fluid losses are adequate guides for replacement of fluids and electrolytes. An increase in body weight is a warning of overhydration.The content of the solution used for replacement is dictated by the route of fluid output-whether from the gastrointestinal tract, the skin, or the kidneys. Insensible losses (by perspiration and respiration) are fairly static. Except to replace extrarenal losses, parenteral administration of normal saline solution in the immediate postoperative period is contraindicated. Mistakes in replacement methods, especially those causing overhydration, are particularly hazardous for elderly patients.     

Good manufacturing practices — A means of controlling biodeterioration

Control of biodeterioration and all aspects of product or operational safety depend upon good manufacturing practices and one of the most effective methods which has been developed to ensure this is by hazard analysis of critical control points (HACCP). This is an all embracing philosophy which examines the risk of microbiological biodeterioration from both the survival of spoilage micro-organisms to processing conditions or contamination at all stages of manufacture, and builds in the relevant quality assurance standards and processing specifications to minimise the risk of biodeterioration of the product and does not rely solely upon the analysis of the finished product. For manufacturers this requires knowledge and control of the microbiological quality of the raw materials, packaging components and processing environment; a validation of the ability of any in-process stages to destroy both pathogenic or spoilage micro-organisms and the effectiveness of the preservative system throughout the shelf-life of the product.     

Cancer of the liver; needle biopsy as a means of detection

Needle biopsy of the liver was done in 25 patients suspected of having hepatic cancer. The results of biopsy were "positive" in 19 cases, and cancer later was proven to be absent in the livers of four of the other six. Multiple biopsy increased the incidence of positive findings. The procedure obviously provides no false-positive tests. It is recommended for the detection of hepatic neoplasm in patients who would otherwise require surgical exploration for diagnosis.     

PTENless means more

Recent studies indicate that certain key molecules that are vital for various developmental processes, such as Wnt, Shh, and Notch, cause cancer when dysregulated. PTEN, a tumor suppressor that antagonizes the PI3 kinase pathway, is the newest one on the list. The biological function of PTEN is evolutionarily conserved from C. elegans to humans, and the PTEN-controlled signaling pathway regulates cellular processes crucial for normal development, including cell proliferation, soma growth, cell death, and cell migration. In this review, we will focus on the function of PTEN in murine development and its role in regulating stem cell self-renewal and proliferation. We will summarize the organomegaly phenotypes associated with Pten tissue-specific deletion and discuss how PTEN controls organ size, a fundamental aspect of development. Last, we will review the role of PTEN in hormone-dependent, adult-onset mammary and prostate gland development.     

This means war

Does a role-playing game reveal any new insights into the factors holding back the UK biotech sector?     

Plug‐in tests for nonequivalence of means of independent normal populations

In this paper, we consider the problem of testing nonequivalence of several independent normal population means. It is a well‐known problem to test the equality of several means using the analysis of variance (ANOVA). Instead of determining the equality, one may consider more flexible homogeneity, which allows a predetermined level of difference. This problem is known as testing nonequivalence of populations. We propose the plug‐in statistics for two different measures of variability: the sum of the absolute deviations and the maximum of the absolute deviations. For each test, the least favorable configuration (LFC) to ensure the maximum rejection probability under the null hypothesis is investigated. Furthermore, we demonstrate the numerical studies based on both simulation and real data to evaluate the plug‐in tests and compare these with the range test.