A Teratogenic Deformity Index for Evaluating Impacts of Selenium on Fish Populations

This paper describes a method for using teratogenic deformities in fish as the basis for evaluating impacts of selenium contamination. Teratogenic deformities are reliable bioindicators of selenium toxicosis in fish. They are produced in response to dietary exposure of parent fish and subsequent deposition of selenium in eggs. There is a close parallel between selenium concentrations in eggs, incidence of teratogenic deformities in larvae, and magnitude of reproductive failure. Using these relationships, an index was developed for teratogenic-based assessment of impacts to fish populations. The index is composed of three ratings that signify increasing levels of terata-induced population mortality: 1, negligible impact (<5% population mortality); 2, slight to moderate impact (5–20% population mortality); 3, major impact (>20% population mortality). Each rating is based on the anticipated population-level impact of the corresponding degree of mortality. Teratogenic-based impact assessment provides a conclusive cause–effect linkage between the contaminant and the fish. It is particularly useful for verifying selenium-induced impacts on reproductive success because poor reproduction can be caused by many things—i.e., fluctuating water levels, nest predation, food shortages, poor recruitment, etc. The index given here should be a useful tool for evaluating the effect of selenium on fish populations. Moreover, application of this technique may save considerable time and money by identifying the most efficient use of manpower and funds early in the assessment process.     

Sak, a murine protein-serine/threonine kinase that is related to the Drosophila polo kinase and involved in cell proliferation.

We have isolated murine cDNAs encoding two isoforms of a putative protein-serine/threonine kinase, designated Sak-a and Sak-b, which differ in their noncatalytic C-terminal ends. The kinase domain of Sak is related to the catalytic domains of the Drosophila polo, Saccharomyces cerevisiae CDC5, and murine Snk and Plk kinases, a family of proteins for which a role in controlling cell proliferation has been established (polo, CDC5) or implicated (Snk, Plk). Northern and in situ RNA analyses of Sak gene expression in mouse embryos and adult tissues revealed that expression was associated with mitotic and meiotic cell division. In addition, during embryogenesis, Sak expression was prominent in the respiratory and olfactory mucosa. The pattern of Sak expression and its sequence homology with the polo gene family suggest that the Sak kinase may play a role in cell proliferation. In support of this, cell growth was suppressed by expression of a Sak-a-antisense fragment in CHO cells.     

Attitudes of College Football Officials Regarding NCAA Mouthguard Regulations and Player Compliance

The National Collegiate Athletic Association (NCAA) mandates the use of brightly colored, intraoral mouth- guards by football players to reduce the frequency and severity of craniofacial and intraoral morbidity and mortality, and to enhance the ability of officials to observe player compliance. The purpose of this 12-question mail survey was to determine the attitudes of on-Held game officials regarding current NCAA mouthguard regulations and patterns of utilization by college football players. The sample consisted of all 50 Big East Football Conference officials; a response rate of 100 percent was achieved. Only 42 percent of the officials reported observing all players in compliance, and quarterbacks were identified by others as the least compliant group (52%). The majority (88%) indicated that the 1990 rule for brightly colored mouthguards had been beneficial to them in determining player compliance, and 52 percent reported that this rule had resulted in more frequent use by these athletes. Nearly all officials (96%) indicated that they would issue a warning for noncompliance to the player or coach, rather than charging a timeout for a violation as prescribed by NCAA regulations. The majority (70%) believe current enforcement is appropriate, but expressed the opinion that coaches should be held more accountable for player compliance.     

Successful Pregnancy in the Didmoad Syndrome (Diabetes Insipidus, Diabetes Mellitus, Optic Atrophy, Deafness)

Summary: A case of successful pregnancy in a patient with the complete DIDMOAD syndrome is described. Attention is drawn to the need to monitor fluid balance carefully during and after pregnancy in this condition. The current literature in the area is reviewed.     

Intra-abdominal desmoplastic small cell tumor presenting as an acute abdomen after trauma

The intraperitoneal mass most commonly encountered after blunt abdominal truama is a hematoma. However, one must also consider unusual bulky tumors that can have imaging characteristics similar to those of hematoma. The most typical of these neoplasms is lymphoma, but a desmoplastic small cell tumor also may be observed. The presentation and imaging findings of a desmoplastic small tumor are described.     

The Complex Nature of Interactive Neuroregeneration-Related Molecules

We review the growing list of molecules that may be involved in wound healing in the central nervous system (CNS). It is known that many of these molecules are present during normal development and neoplastic growth in both neural and nonneural tissues, often in areas where pattern formation or tissue remodeling is evident; however, their functional roles are often quite elusive. In order to understand the changes that occur in and around a brain wound, we review proposed functions of neuroregeneration-related molecules in in vitro and in vivo preparations, as well as note their expression in other healing tissues including skin. A hypothesis that wound healing events in the CNS supersede neuritic growth around a lesion is presented. In contrast to the classical view of failed regeneration, there may be significant amounts of circuit reorganization that occur following injury, and such plasticity may be further enhanced by manipulating the molecular environment around a brain wound and in synaptically related structures.     

Glutathione mutagenesis in Salmonella typhimurium is a {gamma}-glutamyltranspeptidase-enhanced process involving active oxygen species

Reduced glutathione (GSH) is mutagenic in Salmonella in thepresence of -glutamyltranspeptidase (GGT), with the highestresponse obtained in strain TA102. Reduced cysteinylglycine,one of the products of GGT metabolism of GSH, is mutagenic inthe absence of GGT. In strain TA102, GSH mutagenesis was dependenton molecular oxygen, enhanced by iron, inhibited by EDTA, desferrioxaminemesylate, mannitol, butylated hydroxyanisole, peroxidase andcatalase, but not by superoxide dismutase. Binding of GSH orits GGT-dependent metabolites to DNA in vitro was not detected.This is consistent with a model of an indirect mechanism ofmutagenesis, i.e. cleavage of GSH by GGT, followed by facileauto-oxidation of the resulting cysteinylglycine, with the productionof free radicals which lead to the (pen)ultimate mutagen, H₂O₂.