Can nurses manage gastrointestinal symptoms arising from pelvic radiation disease?

AIMS: About 17,000 patients receive radiotherapy for pelvic cancer in the UK annually. Up to 50% are left with altered bowel function affecting quality of life. The UK National Cancer Survivorship Initiative Vision acknowledges that the needs of cancer survivors are not being met and challenges professionals to develop new models of care. MATERIALS AND METHODS: A prospective, observational qualitative study was carried out to assess whether nurse-delivered care is feasible for patients with radiotherapy-induced bowel dysfunction. The experience of a senior nurse, directed by an algorithm of investigation with a comprehensive treatment pathway, is reported. RESULTS: Over 12 months, 59 new and 103 follow-up appointments were managed by the nurse. In total, 37 women and 73 men, with a median age of 69 years, were seen; 9 had been treated for gastrointestinal, 33 for gynaecological and 68 for urological cancers, 26 months (median) previously. Sixty minutes (new consultations) (median, range 35-80) and 40 minutes (follow-up consultations) (range 20-85) were required. Ordering investigations, treatment initiation, long-term care planning and discharge seemed to be manageable in 83% of patients. CONCLUSION: An experienced nurse, working within a defined scope of practice, with medical support can manage care in patients with mild or moderate symptoms arising after pelvic radiotherapy. An ongoing randomised controlled trial is assessing patient outcomes.

Effects of whole-body VX vapor exposure on lethality in rats.

Male and female rats were whole-body exposed to VX vapor in a 1000-L single-pass exposure chamber. Estimated exposure dosages producing lethal (LCT50) effects in 50% of exposed male and female rats were established for 10, 60, and 240 min exposure durations. A potency comparison with GB and GF shows that VX becomes increasingly more potent than these G agents with increasing exposure duration. VX is approximately 4-30 times more potent than GB and 5-15 times more potent than GF. Gender differences in the estimated median dosages were not significant at the 10, 60, and 240 min exposure durations. An empirical toxic load model was developed and the toxic load exponent for lethality (n) in the equation Cn x T = k was determined to be n = 0.92. The VX-G regeneration assay was successfully used as a biomarker for the presence of VX in the blood plasma and RBC fractions of the blood 24 h postexposure.

Gestational age-specific growth parameters for infants born at US military hospitals.

BACKGROUND: Military hospitals currently use gestational age-specific growth curves based on data collected in Denver, Colo, from 1948 to 1961. A number of population and environmental factors and medical practice changes may make these curves nonrepresentative. OBJECTIVE: Determine if presently used growth curves represent norms for infants born in military hospitals and create new curves for use in military hospitals. METHODS: Data were collected from medical records of tertiary- and primary-care military hospitals. We created growth curves created for birth weight, length, and head circumference and compared these curves at gestational ages 23-42 weeks to previously published norms and to 1998 national vital statistics. Racial and ethnic differences between groups were compared. A retrospective analysis of blood-glucose measurements for healthy term infants was performed to identify potential safety issues. RESULTS: Significant increases in growth parameters were noted for infants born in military hospitals. Specific racial and ethnic groups within the military also had an increase when compared with these groups in the United States as a whole. Less than 1% of infants classified as large for gestational age (LGA) according by old standards but average for gestational age (AGA) according to new curves experienced hypoglycemia. CONCLUSION: Published growth curves may not represent infants born in military hospitals. Term infants born in military hospitals as a group and in racial and ethnic subgroups are larger than term infants born in US civilian hospitals. Prospective use of curves will help to validate their long-term applicability in military and civilian nurseries.

Quantitation of fluoride ion released sarin in red blood cell samples by gas chromatography-chemical ionization mass spectrometry using isotope dilution and large-volume injection.

A new method for measuring fluoride ion released isopropyl methylphosphonofluoridate (sarin, GB) in the red blood cell fraction was developed that utilizes an autoinjector, a large-volume injector port (LVI), positive ion ammonia chemical ionization detection in the SIM mode, and a deuterated stable isotope internal standard. This method was applied to red blood cell (RBC) and plasma ethyl acetate extracts from spiked human and animal whole blood samples and from whole blood of minipigs, guinea pigs, and rats exposed by whole-body sarin inhalation. Evidence of nerve agent exposure was detected in plasma and red blood cells at low levels of exposure. The linear method range of quantitation was 10-1000 pg on-column with a detection limit of approximately 2-pg on-column. In the course of method development, several conditions were optimized for the LVI, including type of injector insert, injection volume, initial temperature, pressure, and flow rate. RBC fractions had advantages over the plasma with respect to assessing nerve agent exposure using the fluoride ion method especially in samples with low serum butyrylcholinesterase activity.

Partnership and promise: evolution of the African river-blindness campaigns.

This article describes the evolution of the partnership, between various health and developmental agencies, that has sustained the campaign against river blindness in Africa. The international community was oblivious to the devastating public-health and socio-economic consequences of onchocerciasis until towards the end of the 1960s and the beginning of the 1970s. Then a 'Mission to West Africa', supported by the United Nations Development Programme, and a visit to the sub-region by the president of the World Bank culminated, in 1974, in the inauguration of the Onchocerciasis Control Programme in West Africa (OCP). OCP was a landmark event for the World Bank as it represented its first ever direct investment in a public-health initiative. The resounding success of the OCP is a testimony to the power of the partnership which, with the advent of the Mectizan Donation Programme, was emboldened to extend the scope of its activities to encompass the remaining endemic regions of Africa outside the OCP area. The progress that has been made in consolidating the partnership is discussed in this article. The prospects of adapting the various strategies of the African Programme for Onchocerciasis Control, to entrench an integrated approach that couples strong regional co-ordination with empowerment of local communities and thereby address many other health problems, are also explored.

APOC's strategy of community-directed treatment with ivermectin (CDTI) and its potential for providing additional health services to the poorest populations. African Programme for Onchocerciasis Control.

Since its inauguration in 1995, the African Programme for Onchocerciasis Control (APOC) has made significant progress towards achieving its main objective: to establish sustainable community-directed treatment with ivermectin (CDTI) in onchocerciasis-endemic areas outside of the remit of the Onchocerciasis Control Programme in West Africa (OCP). In the year 2000, the programme, in partnership with governments, non-governmental organizations and the endemic communities themselves, succeeded in treating 20,298,138 individuals in 49,654 communities in 63 projects in 14 countries. Besides the distribution of ivermectin, the programme has strengthened primary healthcare (PHC) through capacity-building, mobilization of resources and empowerment of communities. The community-directed-treatment approach is a model that can be adopted in developing other community-based health programmes. The approach has also made it possible to bring to the poor some measure of intervention in some other healthcare programmes, such as those for malaria control, eye care, maternal and child health, nutrition and immunization. CDTI presents, at all stages of its implementation, a unique window of opportunity for promoting the functional integration of healthcare activities. For this to be done successfully and in a co-ordinated manner, adequate funding of CDTI within PHC is as important as an effective sensitization of the relevant policy-makers, healthworkers and communities on the value of integration (accompanied by appropriate training at all levels). Evaluation of the experiences in integration of health services, particularly at community level, is crucial to the success of the integration.

Cloning and functional characterization of an NAD(+)-dependent DNA ligase from Staphylococcus aureus.

A Staphylococcus aureus mutant conditionally defective in DNA ligase was identified by isolation of complementing plasmid clones that encode the S. aureus ligA gene. Orthologues of the putative S. aureus NAD(+)-dependent DNA ligase could be identified in the genomes of Bacillus stearothermophilus and other gram-positive bacteria and confirmed the presence of four conserved amino acid motifs, including motif I, KXDG with lysine 112, which is believed to be the proposed site of adenylation. DNA sequence comparison of the ligA genes from wild type and temperature-sensitive S. aureus strain NT64 identified a single base alteration that is predicted to result in the amino acid substitution E46G. The S. aureus ligA gene was cloned and overexpressed in Escherichia coli, and the enzyme was purified to near homogeneity. NAD(+)-dependent DNA ligase activity was demonstrated with the purified enzyme by measuring ligation of (32)P-labeled 30-mer and 29-mer oligonucleotides annealed to a complementary strand of DNA. Limited proteolysis of purified S. aureus DNA ligase by thermolysin produced products with apparent molecular masses of 40, 22, and 21 kDa. The fragments were purified and characterized by N-terminal sequencing and mass analysis. The N-terminal fragment (40 kDa) was found to be fully adenylated. A fragment from residues 1 to 315 was expressed as a His-tagged fusion in E. coli and purified for functional analysis. Following deadenylation with nicotinamide mononucleotide, the purified fragment could self-adenylate but lacked detectable DNA binding activity. The 21- and 22-kDa C-terminal fragments, which lacked the last 76 amino acids of the DNA ligase, had no adenylation activity or DNA binding activity. The intact 30-kDa C terminus of the S. aureus LigA protein expressed in E. coli did demonstrate DNA binding activity. These observations suggest that, as in the case with the NAD(+)-dependent DNA ligase from B. stearothermophilus, two independent functional domains exist in S. aureus DNA ligase, consisting of separate adenylation and DNA binding activities. They also demonstrate a role for the extreme C terminus of the ligase in DNA binding. As there is much evidence to suggest that DNA ligase is essential for bacterial survival, its discovery in the important human pathogen S. aureus indicates its potential as a broad-spectrum antibacterial target for the identification of novel antibiotics.

Orphan G protein-coupled receptors: from DNA to drug targets.

Although G protein-coupled receptors (GPCRs) are the most numerous therapeutic targets to date, ligands remain unknown for approximately two-thirds of these receptors. The challenge in the post-genomic era is to evaluate the role of these 'orphan' GPCRs in normal physiology and disease, and to develop new therapeutics based on this information. A prevalent strategy to determine the function of these orphan GPCRs is to identify specific ligands that conditionally modulate their function. These ligands can then be used to explore the role of the receptor-ligand pair in relevant models of disease. Some promise is emerging from this infant field of functional genomics as several recently deorphanized GPCRs may be potential drug targets for many diseases, including obesity, cardiovascular disease, inflammation and cancer.

PARP determines the mode of cell death in skin fibroblasts, but not keratinocytes, exposed to sulfur mustard.

Sulfur mustard is cytotoxic to dermal fibroblasts as well as epidermal keratinocytes. We demonstrated that poly(ADP-ribose) polymerase (PARP) modulates Fas-mediated apoptosis, and other groups and we have shown that PARP plays a role in the modulation of other types of apoptotic and necrotic cell death. We have now utilized primary dermal fibroblasts, immortalized fibroblasts, and keratinocytes derived from PARP(-/-) mice and their wildtype littermates (PARP(+/+)) to determine the contribution of PARP to sulfur mustard toxicity. Following sulfur mustard exposure, primary skin fibroblasts from PARP-deficient mice demonstrated increased internucleosomal DNA cleavage, caspase-3 processing and activity, and annexin V positivity, compared to those derived from PARP(+/+) animals. Conversely, propidium iodide staining, PARP cleavage patterns, and random DNA fragmentation revealed a dose-dependent increase in necrosis in PARP(+/+) but not PARP(-/-) cells. Using immortalized PARP(-/-) fibroblasts stably transfected with the human PARP cDNA or with empty vector alone, we show that PARP inhibits markers of apoptosis in these cells as well. Finally, primary keratinocytes were derived from newborn PARP(+/+) and PARP(-/-) mice and immortalized with the E6 and E7 genes of human papilloma virus. In contrast to fibroblasts, keratinocytes from both PARP(-/-) and PARP(+/+) mice express markers of apoptosis in response to sulfur mustard exposure. The effects of PARP on the mode of cell death in different skin cell types may determine the severity of vesication in vivo, and thus have implications for the design of PARP inhibitors to reduce sulfur mustard pathology.

Isolation and characterization of constitutively active mutants of mammalian adenylyl cyclase.

A genetic screen in Saccharomyces cerevisiae identified mutations in mammalian adenylyl cyclase that activate the enzyme in the absence of G(s)alpha. Thirteen of these mutant proteins were characterized biochemically in an assay system that depends on a mixture of the two cytosolic domains (C(1) and C(2)) of mammalian adenylyl cyclases. Three mutations, I1010M, K1014N, and P1015Q located in the beta4-beta5 loop of the C(2) domain of type II adenylyl cyclase, increase enzymatic activity in the absence of activators. The K1014N mutation displays both increased maximal activity and apparent affinity for the C(1) domain of type V adenylyl cyclase in the absence of activators of the enzyme. The increased affinity of the mutant C(2) domain of adenylyl cyclase for the wild type C(1) domain was exploited to isolate a complex containing VC(1), IIC(2), and G(s)alpha-guanosine 5'-3-O-(thio)triphosphate (GTPgammaS) in the absence of forskolin and a complex of VC(1), IIC(2), forskolin, and P-site inhibitor in the absence of G(s)alpha-GTPgammaS. The isolation of these complexes should facilitate solution of crystal structures of low activity states of adenylyl cyclase and thus determination of the mechanism of activation of the enzyme by forskolin and G(s)alpha.

Role of poly(ADP-ribose) polymerase (PARP) in DNA repair in sulfur mustard-exposed normal human epidermal keratinocytes (NHEK).

We previously reported that, in normal human epidermal keratinocytes (NHEK) cultures exposed to the alkylating compound sulfur mustard (bis-(2-chloroethyl) sulfide, HD, 0.3-1 mM), there is a rapid (< or =1 h) activation (100% above unexposed control) of the DNA repair enzyme DNA ligase I (130 kD) followed by a first-order decay (1-5 h). The DNA ligase activation is accompanied by a time-dependent (0.5-4 h) and significant DNA repair. Inhibition of another putative DNA repair enzyme, poly(ADP-ribose) polymerase (PARP), by using 3-amino benzamide does not affect DNA ligase activation following HD exposure, but increases the half-life of the activated enzyme threefold. To examine the role of PARP in HD-induced DNA ligase activation and subsequent DNA repair, we conducted studies using cultured keratinocytes in which the level of PARP had been selectively lowered (> or =85%) by the use of induced expression of antisense RNA. In these cells, there was no stimulation of DNA ligase up to 3 h, and a small stimulation (ca. 30% above unexposed control at 5-6 h after HD exposure. A time-course (0.5-6 h) study of DNA repair in HD-exposed PARP-deficient keratinocytes revealed a much slower rate of repair compared with HD-exposed NHEK. The results suggest an active role of PARP in DNA ligase activation and DNA repair in mammalian cells, and also indicate that modulation of PARP-mediated mechanisms may provide a useful approach in preventing HD toxicity.

Intervention of sulfur mustard toxicity by downregulation of cell proliferation and metabolic rates.

Metabolically active and proliferating basal cells in the skin are most sensitive to the potent skin blistering chemical warfare compound HD (bis-(2-chloroethyl) sulfide). We previously described a Ca2+-dependent mechanism of HD (0.3-1 mM) toxicity that was inhibited by the cell-permeant Ca2+ chelator BAPTA AM (1,2-bis(O-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid acetoxymethyl ester). We describe some cellular effects of BAPTA AM that suggest a mechanism for its protective action. Monolayer log-phase normal human epidermal keratinocytes were incubated (37 degrees C) first in keratinocyte growth medium (KGM) containing BAPTA AM (10-40 microM) for 30 min and then in KGM alone overnight prior to evaluation. The BAPTA AM inhibited cell growth in a concentration-dependent manner with some cellular degeneration above 30 microM (light microscopy). At 20-30 microM, BAPTA AM also inhibited cellular metabolic processes, as evidenced by a lower incorporation of [3H]-thymidine (DNA synthesis, 54 +/- 5%), [3H]-uridine (RNA synthesis, 29 +/- 6%) and [14C]-valine (protein synthesis, 12 +/- 2%) as well as a lower protein content per culture (30 +/- 3%) compared with corresponding untreated controls. However, 20-30 microM BAPTA AM did not cause any demonstrable cytopathology based on morphological (electron microscopy) as well as biochemical (lactate dehydrogenase release, an indicator of cell viability loss) criteria, indicating a lack of acute toxicity. These results suggest that a mechanism of protection by BAPTA AM against HD may be via decreasing some metabolic, and therefore proliferative, rates.

Economic impact of onchocerciasis control through the African Programme for Onchocerciasis Control: an overview.

This note overviews several studies that have been conducted on the economic impact of onchocerciasis (river blindness) control through the African Programme for Onchocerciasis Control (APOC). A cost-benefit analysis of the APOC concludes that the programme is highly cost-effective. The economic rate of return (ERR) is 17% if benefits are considered in accordance with the stated objective of the programme (i.e. the achievement of long-term, sustainable, ivermectin-delivery systems). However, the cost-benefit analysis significantly under-estimates the net benefits from the APOC, since it considers, for ease of quantification, only the reduction in blindness as the principal benefit accruing from control activities. Recent studies, summarized here, have shown that there may be substantial benefits (in terms of enhanced productivity, increased household-level welfare, and reduced health-related expenditure, for instance) resulting from the reduction of the skin-related symptoms associated with the disease.

Sth1p, a Saccharomyces cerevisiae Snf2p/Swi2p homolog, is an essential ATPase in RSC and differs from Snf/Swi in its interactions with histones and chromatin-associated proteins.

The essential Sth1p is the protein most closely related to the conserved Snf2p/Swi2p in Saccharomyces cerevisiae. Sth1p purified from yeast has a DNA-stimulated ATPase activity required for its function in vivo. The finding that Sth1p is a component of a multiprotein complex capable of ATP-dependent remodeling of the structure of chromatin (RSC) in vitro, suggests that it provides RSC with ATP hydrolysis activity. Three sth1 temperature-sensitive mutations map to the highly conserved ATPase/helicase domain and have cell cycle and non-cell cycle phenotypes, suggesting multiple essential roles for Sth1p. The Sth1p bromodomain is required for wild-type function; deletion mutants lacking portions of this region are thermosensitive and arrest with highly elongated buds and 2C DNA content, indicating perturbation of a unique function. The pleiotropic growth defects of sth1-ts mutants imply a requirement for Sth1p in a general cellular process that affects several metabolic pathways. Significantly, an sth1-ts allele is synthetically sick or lethal with previously identified mutations in histones and chromatin assembly genes that suppress snf/swi, suggesting that RSC interacts differently with chromatin than Snf/Swi. These results provide a framework for understanding the ATP-dependent RSC function in modeling chromatin and its connection to the cell cycle.

Recovery from the lethal effects of saxitoxin: a therapeutic window for 4-aminopyridine (4-AP).

We have shown that saxitoxin (STX) induced lethality can be reversed by 4-AP when it is administered at the time of respiratory arrest [Benton, B. J., Spriggs, D. L., Capacio, B. R. and Chang, F.-C. T. (1995) 4-Aminopyridine antagonizes the lethal effects of saxitoxin (STX) and tetrodotoxin (TTX). International Society of Toxicology, 5th Pan American Symposium on Animal, Plant and Microbial Toxins, Frederick, MD. July/August 1995, p. 217]. The purpose of this study was to determine whether 4-AP's efficacy could be enhanced further when administered at different times relative to STX intoxication. The animals used in this study were chronically instrumented for concurrent recordings of diaphragm electromyogram (DEMG), neck skeletal muscle electromyogram, Lead II electrocardiogram, and electrocorticogram (ECoG). There were five groups of unanesthetized guinea pigs. The first group served as 4-AP controls and received a 2 mg/kg i.m. dose of 4-AP. The four remaining groups were given a lethal dose of STX (5 microg/kg i.m.); the second group, STX controls, received no 4-AP; the third group, the 4-AP treatment group, received 4-AP immediately following cardiorespiratory collapse; the fourth group was the 4-AP/STX co-administration group and 4-AP was given concurrently with STX; and the fifth group was the 4-AP pretreatment group in which 4-AP was given 10 min before STX. At the point of STX-induced cardiorespiratory collapse, the guinea pigs were ventilated and given an i.p. injection of sodium bicarbonate. Results showed that 4-AP prevented cardiorespiratory collapse in 3/7 animals in the 4-AP pretreatment group. Also, 4-AP in conjunction with artificial ventilation and sodium bicarbonate accelerated recovery from STX-induced cardiorespiratory collapse in all the treatment groups compared to the STX controls.

Cla4p, a Saccharomyces cerevisiae Cdc42p-activated kinase involved in cytokinesis, is activated at mitosis.

Yeasts have three functionally redundant G1 cyclins required for cell cycle progression through G1. Mutations in GIN4 and CLA4 were isolated in a screen for mutants that are inviable with deletions in the G1 cyclins CLN1 and CLN2. cln1 cln2 cla4 and cln1 cln2 gin4 cells arrest with a cytokinesis defect; this defect was efficiently rescued by CLN1 or CLN2 expression. GIN4 encodes a protein with strong homology to the Snflp serine/threonine kinase. Cla4p is homologous to mammalian p21-activated kinases (PAKs) (kinases activated by the rho-class GTPase Rac or Cdc42). We developed a kinase assay for Cla4p. Cla4p kinase was activated in vivo by the GTP-bound form of Cdc42p. The specific activity of Cla4p was cell cycle regulated, peaking near mitosis. Deletion of the Cla4p pleckstrin domain diminished kinase activity nearly threefold and eliminated in vivo activity. Deletion of the Cla4p Cdc42-binding domain increased kinase activity nearly threefold, but the mutant only weakly rescued cla4 function in vivo. This suggests that kinase activity alone is not sufficient for full function in vivo. Deletion of the Cdc42-binding domain also altered the cell cycle regulation of kinase activity. Instead of peaking at mitosis, the mutant kinase activity exhibited reduced cell cycle regulation and peaked at the G1/S border. Cla4p kinase activity was not reduced by mutational inactivation of gin4, suggesting that Gin4p may be downstream or parallel to Cla4p in the regulation of cytokinesis.

Pharmacokinetics and pharmacodynamics of 4-aminopyridine in awake guinea pigs.

The selective blockade of potassium channels on excitable membranes by 4-aminopyridine (4-AP) leads to facilitation of neurotransmitter release at a wide variety of synapses. This compound has been shown to be efficacious against lethality induced by saxitoxin (STX) and tetrodotoxin (TTX) in guinea pigs. To characterize the actions of 4-AP in guinea pigs we have investigated its pharmacokinetics (PK) and pharmacodynamics following a 2 mg/kg, intramuscular (im) dose in awake chronically instrumented (IN) animals. Animals were chronically instrumented for electrophysiologic recordings of diaphragmatic electromyogram (DEMG), lead II electrocardiogram (ECGII) and electrocorticogram (ECoG). Also, PK studies were carried out in uninstrumented (UN) guinea pigs. Blood and electrophysiologic data were collected at predetermined time intervals up to 4 hours post 4-AP administration. High performance liquid chromatography was used to determine plasma 4-AP concentrations. For IN and UN animals, plasma concentration-time data best fit a one-compartment model, and PK parameter estimates were similar for both groups. Peak plasma levels were found to occur between 16 and 17 min, and the half-lives of elimination were 65 and 71 min for IN and UN animals respectively. Heart and respiratory rates were elevated as early as 5 and 15 min respectively in response to 4-AP administration. The duration of action was approximately 1-1.5 half-lives of elimination beyond peak plasma levels. Maximum ECoG responses were observed between 12-15 min after 4-AP injection; some residual drug effects were still apparent at 240 min. The difference between the heart and respiratory rates and ECoG profiles suggests that these different physiological systems respond with varying degrees of sensitivity to plasma 4-AP concentrations. The stimulation of these systems is consistent with the action of 4-AP in reversing STX- and TTX-induced cardiorespiratory depression and decreased ECoG power in guinea pigs.

4-Aminopyridine reverses saxitoxin (STX)- and tetrodotoxin (TTX)-induced cardiorespiratory depression in chronically instrumented guinea pigs.

The extent to which cardiorespiratory infirmity and other sublethal effects of saxitoxin (STX) and tetrodotoxin (TTX) can be reversed by 4-aminopyridine (4-AP) was investigated in guinea pigs chronically instrumented for the concurrent electrophysiological recordings of electrocorticogram (ECoG), diaphragmatic electromyogram (DEMG), Lead II electrocardiogram, and neck skeletal muscle electromyogram. Animals were intoxicated with either STX or TTX (2 and 3 microg/kg, im) to produce a state of progressive cardiorespiratory depression (depicted by decreasing DEMG amplitude, bradypnea, and bradycardia). At the point where cardiorespiratory performance was most seriously compromised (approximately 30 min posttoxin), 4-AP (1 or 2 mg/kg, im) was administered. The therapeutic effect of 4-AP was striking in that, within minutes, the toxin-induced diaphragmatic blockade, bradypnea, bradycardia, and depressed cortical activity were all restored to a level either comparable to, or surpassing, that of control. The optimal 4-AP dose level was determined to be 2 mg/kg (im) based on analyses of cardiorespiratory activity profiles throughout the course of intoxication and 4-AP treatment. At the dose levels (either 1 or 2 mg/kg) used to restore ventilatory function and cardiovascular performance, 4-AP produced no sign of seizures and convulsions. Although less serious secondary effects such as cortical excitant/arousal effect (indicated by ECoG power spectral analysis) and transient periods of skeletal muscle fasciculation were observed, these events were of minor concern particularly in view of the remarkable therapeutic effects of 4-AP.