Targeting oxidative stress component in the therapeutics of epilepsy

The role of free radical-mediated reactions in human neuropathology continues to attract significant interest. Oxidative injury produced by free radicals may play a role in the initiation and progression of epilepsy and, therapies aimed at reducing oxidative stress may ameliorate tissue damage and favorably alter the clinical course. The prevalence of epilepsy increases with age, and mitochondrial oxidative stress is a leading mechanism of aging and age-related degenerative disease, signifying a further involvement of mitochondrial dysfunction in seizure generation. Oxidative stress occurs when the generation of reactive oxygen species in a system exceeds the body's ability to neutralize and eliminate them, thus creating an imbalance or over abundance of free radicals. Therefore, it is imperative to maintain oxidative balance and control in the brain, and this is tightly regulated by antioxidants. In the last two decades, there has been an explosive interest in the role of antioxidants or neuroprotectants in clinical as well as experimental models of epilepsy. In this regard, the present review is intended to discuss the current state of knowledge pertaining to neuroprotection in epileptic conditions by employing diverse chemical agents including conventional as well as novel anti-epileptic drugs, and to highlight the efficacy of distinct neuroprotective strategies for preventing or treating epilepsy.     

Contribution of nerve biopsy to unclassified neuropathy

OBJECTIVES: To evaluate the diagnostic yield of nerve biopsy in patients with peripheral neuropathy of undetermined cause despite extensive diagnostic workup. METHODS: From November 2001 through January 2004, 38 patients underwent nerve biopsy because of unclassified neuropathy. RESULTS: The etiology of the neuropathies could be defined in 14 patients (37%), i.e. in 15% of chronic symmetric, 30% of chronic asymmetric, 50% of subacute symmetric and 62.5% of subacute asymmetric neuropathies. The biopsy was diagnostic in 6 patients (16%), where it showed a vasculitis, and supportive in 8 patients (21%). CONCLUSIONS: The contribution of nerve biopsy to the diagnosis of peripheral neuropathy was highest in acute and subacute asymmetric forms of neuropathy and lowest in chronic symmetric forms. The main indication for nerve biopsy remains the diagnosis of vasculitic neuropathy, a potentially treatable disorder.     

George Peters Award. Microscopic anatomy within the nipple: implications for nipple-sparing mastectomy

BACKGROUND: Precise anatomical relationships between ducts and vasculature within the nipple remain unknown. This study investigated nipple microvessels and their position relative to ducts. METHODS: Nipple and duct bundle cross-sectional areas were measured in 48 specimens. Vessels located within the central duct bundle or within a peripheral rim were counted in 7 non-irradiated and 5 irradiated nipples. RESULTS: Mean nipple diameter was 11.1 mm and duct bundle diameter 5.2 mm. A 2-mm and a 3-mm peripheral rim of nipple tissue would result in complete duct excision in 96% and 87% of sections, respectively. Twenty-nine percent of vessels are located in the duct bundle. A 2-mm rim contains 50%; a 3-mm rim contains 66%. Similar proportions were seen in irradiated nipples. CONCLUSIONS: This study describes a strategy to balance duct removal with vascular preservation. Ducts can be excised leaving a rim of nipple tissue that contains a large proportion of microvessels.     

Partial-breast irradiation: towards a replacement for whole-breast irradiation?

Largely thanks to all of the investigators and patients who have participated in randomized breast-conservation trials, many women facing a diagnosis of breast cancer today can conserve their breast with the help of adjuvant radiation therapy. A standard course of radiation consists of 5-7 weeks of daily radiation treatments delivered to the whole breast. The success of this treatment has led investigators to attempt to determine whether the same control can be achieved while decreasing the volume of breast tissue irradiated, thus allowing treatment to be delivered in a shorter period of time. This approach could alleviate time and logistical problems faced by patients during their course of treatment as well as improving overall cost-effectiveness. It can also allow complete avoidance of the adjacent heart and lung tissue in the radiation treatment portal. Partial-breast irradiation (the delivery of radiation to the resection cavity, plus a safety margin) delivered in just hours or days, is currently under investigation. Although relatively new, its use is growing rapidly and many institutional and cooperative group trials are quickly enlisting patients, while physicians are gaining experience in a variety of partial-breast irradiation techniques.     

Effect of Bauhinia racemosa stem bark on N-nitrosodiethylamine-induced hepatocarcinogenesis in rats

The aim of this study is to investigate the antioxidant defense system induced by the methanol extract of Bauhinia racemosa L.(MEBR) against N-nitrosodiethylamine (NDEA)-induced hepatocarcinogenesis in Wister albino rats. The effects of MEBR on surface visible macroscopic (Morphometry) liver lesions (neoplastic nodules) and the levels of serum enzymes, lipid peroxidation and antioxidants were evaluated in NDEA-induced hepatocarcinogenesis in rats. In rats treated, with NDEA, significantly elevated levels of serum enzymes (SGOT, SGPT and ALP), bilirubin and decreased levels of protein and uric acid were observed. Significantly elevated amount of malondialdehyde (MDA), the end product of lipidperoxidation, indicated higher levels of lipid peroxidation, which was accompanied by significantly decreased levels of antioxidants like vitamin C, vitamin E, reduced glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT). Administration of MEBR was able to suppress nodule development/hepatocellular lesion formation in rats. The extract treatment increases in antioxidant levels and dramatic decreases in lipid peroxidation levels. MEBR also produced a protective effect by decreasing the level of serum enzymes, bilirubin and increased the protein and uric acid levels. The results suggest that MEBR exert chemopreventive effects by suppressing nodule development and decreasing lipid peroxidation and enhancing the levels of antioxidants in NDEA carcinogenesis by reducing the formation of free radicals.     

Five‐grass pollen 300IR SLIT tablets: efficacy and safety in children and adolescents

Halken S, Agertoft L, Seidenberg J, Bauer C‐P, Payot F, Martin‐Muñoz MF, Bartkowiak‐Emeryk M, Vereda A, Jean‐Alphonse S, Melac M, Le Gall M, Wahn U. Five‐grass pollen 300IR SLIT tablets: efficacy and safety in children and adolescents.
Pediatr Allergy Immunol 2010: 21: 970–976.
© 2010 John Wiley & Sons A/S The efficacy and safety of five‐grass pollen 300IR sublingual immunotherapy (SLIT) tablets (Stallergènes SA, France) have previously been demonstrated in paediatric patients. This report presents additional data concerning efficacy at pollen peak, efficacy and safety according to age, nasal and ocular symptoms, use of rescue medication, satisfaction with treatment and compliance. Children (5–11 yr) and adolescents (12–17 yr) with grass pollen–allergic rhinoconjunctivitis were included in a multinational, randomized, double‐blind, placebo‐controlled study and received either a 300IR five‐grass pollen tablet or placebo daily in a pre‐ (4 months) and co‐seasonal protocol. The severity of six symptoms (sneezing, rhinorrhoea, nasal congestion, nasal and ocular pruritis, and tearing) was scored, and rescue medication use was recorded daily during the pollen season. Patient satisfaction was recorded at the season end. A total of 161 children and 117 adolescents were evaluated (n = 267). 300IR SLIT was effective over the whole season (p = 0.0010) and at the pollen peak (p = 0.0009). The adjusted mean difference between 300IR and placebo groups was significant for both nasal (p = 0.0183) and ocular (p < 0.0001) symptoms. Rescue medication use was statistically lower in the SLIT group during the pollen season and at the pollen peak (both p < 0.05). More patients in the SLIT group were satisfied with their treatment compared to placebo (83.2% vs. 68.1%, p = 0.0030), and compliance was high (SLIT 93.9% of patients were compliant, placebo 94.8% of patients were compliant). SLIT was well tolerated by children and adolescents. 300IR five‐grass pollen tablets are effective and safe during the pollen season and at the pollen peak in children and adolescents with grass pollen rhinoconjunctivitis.     

Confocal microscopy of genome exposure in normal,cancer, and reverse-transformed cells

Genome exposure studies were carried out on malignant CHO-K1 and C6 rat glioma cells and their respective, phenotypically normal counterparts (reverse-transformed CHO-K1, and both reverse-transformed C6 glioma and normal rat fibroblasts). Cells were subjected to the nick-translation technique previously developed to make visible the exposed (i.e., DNase I-sensitive) nuclear DNA, and examined by both epifluorescence and confocal microscopy. The confocal microscopy, by permitting examination of sections throughout the nucleus, made possible clearer identification of the regions of exposed and sequestered DNA in the cells studied. A peripheral shell of exposed DNA with some discontinuities was displayed in the great majority of the cells with normal phenotype, but in none of the cancer cells. Both types of cells displayed regions of exposed DNA in the nuclear interior, particularly surrounding the nucleoli. In accordance with previous theoretical proposals we postulate: the peripheral nuclear shell of exposed DNA contains differentiation-specific genes that include the specific growth-control genes and that are functional in normal cells but not in cancer; the exposed genes surrounding the nucleoli may represent housekeeping genes active in both normal and cancer cells; and the DNase I-resistant DNA in the interior of the nucleus we postulate to consist for the most part of genes specific to alternative differentiation states and to be sequestered and inactive. Previous differences in evaluation of roles of peripheral and internal DNA sensitivity to DNase I hydrolysis appear to be reconciled by this formulation. Identification of exposed DNA may be useful in cancer diagnosis.     

Increases in adipose and total body weight,but not in lean body mass,associated with subcutaneous administration of Sonic hedgehog‐Ig fusion protein to mice

Sonic hedgehog (Shh) is a member of a family of proteins that are involved in embryonic development. The receptor signaling pathways for Shh persist in adults and stimulation of this pathway has shown therapeutic efficacy in animal models of neurodegeneration/regeneration. This study was conducted to evaluate the safety of repeat dose administration of an IgG fusion protein of Shh (Shh‐Ig) in adult mice. Routine toxicology evaluations were performed. In addition, body composition analysis was conducted by densitometry. Shh‐Ig treatment caused a significant increase in body weight gain relative to controls and a slight increase in liver and spleen weights. The increase in body weight could be largely accounted for by an increase in body fat. The treatment‐related increases in body weight were reversible upon cessation of treatment. Shh‐Ig treatment produced no significant changes in clinical chemistry or hematology. There were no gross or histomorphologic findings in any tissue except for skin and spleen. Microscopic findings in the skin were limited to minimal to slight local epidermal hyperplasia at the sc injection site and increased thickness of the fat layer. In the spleen a slight increase in extramedullary hematopoiesis was seen. This finding is possibly a secondary response following inflammation at the injection site in some animals due to the administration of a foreign protein. This study showed that Shh‐Ig administration was well tolerated. The most significant finding was a reversible increase in body weight. Drug Dev. Res. 57:107–114, 2002. © 2002 Wiley‐Liss, Inc.     

Genome regulation in mammalian cells

A theory is presented proposing that genetic regulation in mammalian cells is at least a two-tiered effect; that one level of regulation involves the transition between gene exposure and sequestration; that normal differentiation requires a different spectrum of genes to be exposed in each separate state of differentiation; that the fiber systems of the cell cytoskeleton and the nuclear matrix together control the degree of gene exposure; that specific phosphorylation of these elements causes them to assume a different organizational network and to impose a different pattern of sequestration and exposure on the elements of the genome; that the varied gene phosphorylation mechanisms in the cell are integrated in this function; that attachment of this network system to specific parts of the chromosomes brings about sequestration or exposure of the genes in their neighborhood in a fashion similar to that observed when microtubule elements attach through the kinetochore to the centromeric DNA; that one function of repetitive sequences is to serve as elements for the final attachment of this fibrous network to the specific chromosomal loci; and that at least an important part of the calcium manifestation as a metabolic trigger of different differentiation states involves its acting as a binding agent to centers of electronegativity, in particular proteins and especially phosphorylated groups, so as to change the conformation of the fiber network that ultimately controls gene exposure in the mammalian cell. It would appear essential to determine what abnormal gene exposures and sequestrations are characteristic of each type of cancer; which agonists, if any, will bring about reverse transformation; and whether these considerations can be used in therapy.