Epilepsy

Oral versus intravenous ibandronic acid: a comparison of treatment options for metastatic bone disease

PURPOSE

This trial is the first to compare directly the clinical response to and safety of oral and intravenous (IV) ibandronic acid for metastatic bone disease.

METHODS

Patients > or =18 years with breast, prostate, lung, urogenital or colon cancer received IV ibandronic acid 6 mg infused over 15 min every 28 days or oral ibandronic acid 50 mg/day. Clinical response was determined using bone scintigraphy, radiography and serum C-terminal telopeptide of type I collagen (S-CTX) at months 3-6. Adverse events and biochemical safety measures were recorded.

RESULTS

A total of 84.6 and 88.5% of patients had a complete/partial response to IV and oral ibandronic acid, respectively. Median percentage decreases in S-CTX were -39 and -35%, respectively. Bone pain scores decreased and analgesic use increased from month 0-3 and were stable from months 3-6. Both formulations improved physical and functioning scores.

CONCLUSION

Oral and IV ibandronic acid for bone metastases have similar efficacy and tolerability.

Quarterly intravenous ibandronate for postmenopausal osteoporosis

Osteoporosis is under-recognized and undertreated among postmenopausal women. Nitrogen-containing bisphosphonates are its first-line pharmacotherapy. Oral bisphosphonate treatment requires stringent dosing guidelines to minimize gastrointestinal irritation and enhance absorption. This paper reviews the efficacy, safety and tolerability of quarterly intravenous ibandronate 3 mg injection, approved in 2006 in the USA and Europe. Quarterly intravenous ibandronate injection has shown superior efficacy to daily oral ibandronate for bone mineral density increase and fracture prevention. No drug-related serious atrial fibrillation events have been reported with intravenous ibandronate. The regimen has a favorable renal safety profile. Quarterly intravenous ibandronate is administered as a simple 15-30-s intravenous injection in a physician's office and provides a beneficial option for patients who are unable to tolerate oral administration.

Modern management of epilepsy: a practical approach

The epilepsies are among the most common serious brain disorders, can occur at all ages, and are characterized by a variety of presentations and causes. Diagnosis of epilepsy remains clinical, and neurophysiological investigations support the diagnosis of the syndrome. Brain imaging is able to identify many of the structural causes of the epilepsies. Current antiepileptic drugs (AEDs) block seizures without influencing the underlying tendency to generate seizures, and are effective in 60-70% of individuals. Several modern drugs are as efficacious as the older medications, but have important advantages including the absence of adverse drug interactions and hypersensitivity reactions. Epilepsy is associated with an increased prevalence of mental health disorders including anxiety, depression, and suicidal thoughts. An understanding of the psychiatric correlates of epilepsy is important to the adequate management of people with epilepsy. Anticipation of common errors in the diagnosis and management of epilepsy is important. Frequent early diagnostic errors include nonepileptic psychogenic seizures, syncope with myoclonus, restless legs syndrome, and REM behavioral disorders, the last mostly in elderly men. Overtreatment with too rapid titration and too high doses or too many AEDs should be avoided. For people with refractory focal epilepsy, vagus nerve stimulation offers palliative treatment with possible mood improvement and neurosurgical resection offers the possibility of a life-changing cure. Potential advances in the management of epilepsy are briefly discussed. This short review summarizes the authors' how-to-do approach to the modern management of people with epilepsy.

[Drug resistance in partial epilepsy: epidemiology, mechanisms, pharmacogenetics and therapeutical aspects]

It has been established that 20-30% of epilepsies are not controlled by antiepileptic drugs. Drug resistance is associated with several major problems, including prognosis, cognitive function, behavior, mortality, cost and quality of life. Apart from classic risk factors for drug resistance, such as neurological, psychiatric, imaging, EEG abnormalities, a high frequency of seizures before medical therapy and complex febrile convulsions, the potential role of multidrug transporters as well as their genetic control and the altered sensitivity of neuronal drug receptors has gained growing attention. In the future, pharmaceutical engineering may bypass these factors. To a certain extent, drug resistance may develop progressively in a neurobiological process and the control of this process could limit its development.

Poly(ADP-ribose) signal in seizures-induced neuron death

Poly(ADP-ribose) is found to be involved in many physiological or pathological processes. It is mainly modulated by poly(ADP-ribose) polymerase (PARP) and poly(ADP-ribose) glycohydrolase (PARG). Either PARP or PARG is associated with the neuronal death in a variety of neurodegenerative diseases. Cumulative data have suggested that poly(ADP-ribose) regulation might have a therapeutic value in neurotoxicity-induced neuron damage, probably due to the inhibition of apoptosis, suppressing of inflammation and activation of cell survival signaling. We hypothesize poly(ADP-ribose) play an important role in seizures-induced neuron death. Seizures can lead to neuron degeneration as for the exitotoxity of glutamate. Recently, it is indicated seizures also can trigger PARP activation. Further investigation is needed to determine whether poly(ADP-ribose) signal is a therapeutic target for seizures-induced injury.

Unilateral hippocampal CA3-predominant damage and short latency epileptogenesis after intra-amygdala microinjection of kainic acid in mice

Mesial temporal lobe epilepsy is the most common, intractable seizure disorder in adults. It is associated with an asymmetric pattern of hippocampal neuron loss within the endfolium (hilus and CA3) and CA1, with limited pathology in extra-hippocampal regions. We previously developed a model of focally-evoked seizure-induced neuronal death using intra-amygdala kainic acid (KA) microinjection and characterized the acute hippocampal pathology. Here, we sought to characterize the full extent of hippocampal and potential extra-hippocampal damage in this model, and the temporal onset of epileptic seizures. Seizure damage assessed at four stereotaxic levels by FluoroJade B staining was most prominent in ipsilateral hippocampal CA3 where it extended from septal to temporal pole. Minor but significant neuronal injury was present in ipsilateral CA1. Extra-hippocampal neuronal damage was generally limited in extent and restricted to the lateral septal nucleus, injected amygdala and select regions of neocortex ipsilateral to the seizure elicitation side. Continuous surface EEG recorded with implanted telemetry units in freely-moving mice detected spontaneous, epileptic seizures by five days post-KA in all mice. Epileptic seizure number averaged 1-4 per day. Hippocampi from epileptic mice 15 days post-KA displayed unilateral CA3 lesions, astrogliosis and increased neuropeptide Y immunoreactivity suggestive of mossy fiber rearrangement. These studies characterize a mouse model of unilateral hippocampal-dominant neuronal damage and short latency epileptogenesis that may be suitable for studying the cell and molecular pathogenesis of human mesial temporal lobe epilepsy.

Mossy fiber sprouting in pilocarpine-induced status epilepticus rat hippocampus: a correlative study of diffusion spectrum imaging and histology

Mossy fiber sprouting (MFS) is the main characteristic of temporal lobe epilepsy (TLE), which is highly correlated with the frequencies of recurrent seizures as well as degrees of severity of TLE. A recent MRI technique, referred to as diffusion spectrum imaging (DSI), can resolve crossing fibers and investigate the intravoxel heterogeneity of water molecular diffusion. Being able to achieve higher accuracy in depicting the complex fiber architecture, DSI may help improve localization of the seizure-induced epileptic foci. In this study, two indices of DSI, which represented the mean diffusivity (MSL) and diffusion anisotropy (DA), were proposed. A correlative study between diffusion characteristics and the severity of MFS was investigated in the pilocarpine-induced status epilepticus (SE) rat model. Nine SE rats and five control rats were studied with MRI and histological Timm's staining. For MSL, no significant correlation was found in the dentate gyrus (DG), r=-0.36; p=0.2017, and positive correlation was found in cornu ammonis (CA3), r=0.62; p=0.0174. The correlation between DA and Timm's score showed positive correlation in DG, r=0.71; p=0.0047, and negative correlation in CA3, r=-0.63; p=0.0151. Our results were compatible with the previous reports on fiber architecture alterations in DG and CA3 subregions. In conclusion, the histological correspondence of DSI indices was demonstrated. With DSI indices, longitudinal follow-up of hippocampal fiber architecture can be achieved to elucidate the pathophysiology of TLE, which might be helpful in disease localization.

Antiepileptic drug resistant rats differ from drug responsive rats in GABA A receptor subunit expression in a model of temporal lobe epilepsy

Epidemiological data indicate that 20-40% of the patients with epilepsy are refractory to treatment with antiepileptic drugs (AEDs). The mechanisms underlying pharmacoresistance in epilepsy are unclear, but several plausible hypotheses have emerged, including loss of AED target sensitivity in the epileptic brain, decreased AED concentrations at brain targets because of localized overexpression of drug efflux transporters in epileptogenic brain tissue, and network alterations in response to brain damage associated with epilepsy. Rat models of epilepsy in which part of the animals are resistant to treatment with AEDs offer a means to investigate the mechanisms underlying AED resistance. In the present study, AED-responsive and AED-resistant rats were selected from a model in which spontaneous recurrent seizures develop after a status epilepticus induced by electrical stimulation of the basolateral amygdala. For selection into responders and nonresponders, epileptic rats were treated over two weeks by phenobarbital. Subsequent histological examination showed neurodegeneration of the CA1, CA3 and dentate hilus in only one of eight responders but five of six nonresponders (P=0.0256). Based on previous studies in AED-resistant rats of this model, we hypothesized that changes in the structure and function of inhibitory GABA(A) receptors may contribute to drug resistance. We therefore analyzed the distribution and expression of several GABA(A) receptor subunits (alpha1, alpha2, alpha 3, alpha 4, alpha 5, beta2/3, and gamma 2) immunohistochemically with specific antibodies in the hippocampal formation of responders, nonresponders and nonepileptic controls. In nonresponders, decreased subunit staining was observed in CA1, CA2, CA3, and dentate gyrus, whereas much less widespread alterations were determined in responders. Furthermore, upregulation of the alpha 4-subunit was observed in the CA1 of nonresponders. Our data suggest that alterations in GABA(A) receptor subtypes may be involved in resistance to AEDs.

The potential role of cyclin-dependent kinase 5 in focal cortical dysplasia

Focal cortical dysplasia (FCD) is the most common malformation of cortical development found in epilepsy surgical series. Characterised by cortical mislamination, dysplastic neurons and, in a subgroup of cases, balloon cells, FCD is potently epileptogenic. Despite decades of study, the underlying aetiology of FCD remains uncertain and research has been hampered by the lack of a good animal model in which to simulate the condition. In this article we review some of the potential molecular mechanisms that might underpin human FCD. In particular we examine the potential role of cyclin-dependent kinase 5 and its principal activator p35 in FCD and estimate the contribution that deregulation of cyclin-dependent kinase 5 might make to the pathogenesis of this condition.

Familial risks for common diseases: etiologic clues and guidance to gene identification

Familial clustering of a disease is a direct indicator of a possible heritable cause, provided that environmental sharing can be excluded. If the familial clustering is lacking, the likelihood of a heritable influence is also small. In the era of genome scans, the consideration of data on heritability should be important in the assessment of the likely success of the genome scan. The availability of a Multigeneration Register in Sweden provides a reliable access to families throughout the last century. This Register has been extensively used to study a number of different diseases through linkage to the Hospital Discharge Register. In the present article we review the obtained and some unpublished results for nine main disease classes. For each of these, familial risks are given for four disease subtypes. As measures of familial clustering we use risks between siblings, twins and spouses. Disease correlation between spouses suggests environmental sharing and a higher correlation between siblings and particularly twins shows heritable effects. We will also comment on the established susceptibility genes and the risks conferred by them. The data suggest high heritabilities for chronic obstructive pulmonary disease, asthma, noninfective enteritis and colitis, cerebral palsy and endocrine and metabolic diseases. Among the performed first-generation genome scans on various diseases, the success appears to be related to the a priori heritability estimates. To our knowledge this is a first attempt to summarize familial risks for a large number of diseases using data from a single population on which reasonable uniform diagnostic criteria have been applied.

Safety considerations with bisphosphonates for the treatment of osteoporosis

Bisphosphonates are the most commonly prescribed medications for the treatment of osteoporosis. Although evidence supports a good safety profile for these agents, numerous tolerability issues have been associated with their use. This review provides an overview of the safety issues associated with the nitrogen-containing class of bisphosphonates and discusses the potential effect of these issues on adherence. The review specifically considers upper gastrointestinal (UGI) adverse events (AEs), renal toxicity, influenza-like illness, osteonecrosis of the jaw and evidence on how to treat or prevent these events. In clinical trials, UGI AEs, including severe events such as oesophageal ulcer, oesophagitis and erosive oesophagitis, have been reported at similar frequencies in placebo- and active-treatment arms. However, postmarketing studies have highlighted UGI AEs as a concern. These studies show that a significant portion of patients are less compliant with administration instructions outside strict clinical trial supervision, and when oral bisphosphonates are not administered as directed, patients are more likely to experience UGI AEs. Some clinical trials with oral bisphosphonates have suggested that a decrease in the frequency of administration may lead to improvement in gastrointestinal tolerability. In the authors' experience, the issue of UGI tolerability can be minimised by explaining to the patient and/or caregiver the importance of following administration instructions. Intravenous (IV) bisphosphonates have been recently approved for use in osteoporosis, offering an alternative regimen for patients with osteoporosis. Earlier generation IV bisphosphonates (e.g. etidronate) have been associated with acute renal failure. Alternatively, late-generation IV bisphosphonates (i.e. ibandronate) have shown a better safety profile in relation to renal toxicity. Influenza-like illness, often referred to as an acute-phase reaction, covers symptoms such as fatigue, fever, chills, myalgia and arthralgia. These symptoms are transitory and self-limiting and usually do not recur after subsequent drug administration. Symptoms of influenza-like illness have been associated with both IV and oral bisphosphonates. Osteonecrosis of the jaw has also been associated with IV bisphosphonate treatment, particularly in patients treated with high doses. A small number of patients with cancer and osteoporosis using oral bisphosphonates have also reported this AE. As osteonecrosis of the jaw is difficult to treat and is often associated with dental procedures and poor oral hygiene, preventive measures seem to be the best management option for patients taking bisphosphonates.Overall, the safety and tolerability profile of the nitrogen-containing bisphosphonates is good, and long-term treatment does not appear to carry a risk of serious AEs. By encouraging adherence to administration instructions physicians can minimise certain complications, such as UGI intolerability. By being aware of other potential safety issues, such as renal impairment, influenza-like illness and osteonecrosis of the jaw, physicians can detect these AEs early in the course of treatment.

Crises não-epilépticas: clínica e terapêutica

Discutir as crises ou os eventos paroxísticos que simulem crises epilépticas, enfatizando as diferenças semiológicas entre elas e as perspectivas terapêuticas. Realizamos uma revisão da literatura, selecionando artigos nas bases de dados Medline e Bireme, a partir dos unitermos: "non-epileptic seizures", "psychogenic seizures". As crises não-epilépticas (CNE) podem ser classificadas em fisiológicas (síncope, migrânea, ataque isquêmico transitório) e em psicogênicas (voluntárias ou não). O padrão-ouro para a diferenciação entre as crises epilépticas e as CNE é o videoeletroencefalograma, mas vários dados semiológicos podem auxiliar esse processo. O tratamento das CNE baseia-se em psicoterapia e em farmacoterapia direcionadas aos transtornos psiquiátricos comórbidos. Apesar de a alta prevalência das CNE e de sua elevada morbidade, são escassos os estudos na literatura nacional. São muitos os desafios diagnósticos e terapêuticos. Assim, o psiquiatra atentar-se à sua ocorrência, evitando iatrogenia, como o uso desnecessário de drogas antiepilépticas.

Health disparities in epilepsy: how patient-oriented outcomes in women differ from men

Epilepsy is a chronic disorder with multiple effects on biological, social, and psychological health. Many of these effects differ between men and women, but only sparse research has specifically addressed the relevance and importance of the differences. Available evidence suggests that men and women with epilepsy have differing rates of employment and driving, and women with epilepsy have increased risk for specific mood disorders such as post-partum depression. National surveys of physicians indicate that many physicians providing care for women with epilepsy have limited knowledge of fundamental concerns such as interactions between antiepileptic drugs and oral contraceptives, and their potential teratogenic effects. Further research and clinical implementation of improved gender-specific care is needed to optimize outcomes for women with epilepsy.

Myths and fallacies about epilepsy among residents of a Karachi slum area

Misconceptions about epilepsy may explain the considerable stigma accompanying it. We aimed to identify such fallacies through questionnaire-based interviews of 487 adult residents of a slum area in Karachi, Pakistan. Of those interviewed, 25% believed that epilepsy was caused by evil spirits, black magic and envy by others – those without a school education were more likely to hold these views ( P < 0.05). Perceived complications included impotence and cancer. Shoe-sniffing was considered a treatment modality by 13%. It appears that misconceptions abound regarding epilepsy's causes, complications and methods of treatment. However, those who had received a school education were less likely to link epilepsy with supernatural phenomena.

Renal safety of intravenous bisphosphonates in the treatment of osteoporosis

Oral bisphosphonates are the mainstay of treatment for osteoporosis but cannot be used in some patients due to gastrointestinal contraindications, gastrointestinal intolerance, malabsorption or the inability to comply with dosing requirements. In such patients, intravenous bisphosphonates are a useful alternative. This review summarises the renal safety issues associated with the use of intravenous bisphosphonates for osteoporosis. Intravenous bisphosphonates are generally well tolerated, which may be a reflection of their selective activity in bone and metabolic stability. Adverse effects on renal function are primarily related to infusion rate and dose. Due to lack of data, no conclusions can be made regarding bisphosphonate safety in patients with intrinsic renal disease or an estimated glomerular filtration rate of < 30 ml/min.

Epileptic seizures and hippocampal damage after cuprizone-induced demyelination in C57BL/6 mice

Epileptic seizures are known to occur in different animal models of demyelination and have also been described in demyelinating diseases of the central nervous system (CNS) such as multiple sclerosis. How myelin deficiency might cause seizures is unknown, but may involve axonal pathology and resultant alterations in neuronal excitability. The cause of seizures occurring in rodent demyelination models is unknown. In the present study, we used EEG/video monitoring to record seizures occurring during chronic demyelination of C57BL/6 mice fed for 12 weeks with 0.2% cuprizone. Furthermore, in the search for a morphological correlate of the seizures, the hippocampal formation was examined histologically. Epileptiform spikes resembling interictal spikes known from chronic epilepsy were recorded in all cuprizone-treated mice, but not in controls. Most cuprizone-treated animals exhibited generalized tonic-clonic seizures upon stress-inducing stimuli. In addition to the known demyelination of the corpus callosum, massive demyelination was found in the hippocampal formation. This was associated with neuronal alterations, including a loss of neurons in the hilus of the dentate gyrus. In view of the role of the dentate gyrus in epileptogenesis, demyelination leading to axonal pathology and thus neuronal damage as observed in the hilus may be causally involved in the paroxysmal alterations observed after prolonged treatment with cuprizone. The present data suggest a potential role of the hippocampal formation for seizures occurring as a consequence of neuronal damage secondary to CNS demyelination.

Management of cancer treatment-induced bone loss in early breast and prostate cancer -- a consensus paper of the Belgian Bone Club

Cancer treatment-induced bone loss (CTIBL) is one of the most important side effects of adjuvant antineoplastic treatment in hormone-dependent neoplasms. Chemotherapy, GnRH analogs and tamoxifen can induce marked bone loss in premenopausal women with early breast cancer. Aromatase inhibitors (AIs) are replacing tamoxifen as the preferred treatment for postmenopausal women. As a class effect, steroidal (exemestane) and non-steroidal (anastrozole and letrozole) AIs increase bone turnover and cause bone loss (4%-5% over 2 years). When compared to tamoxifen, the risk of getting a clinical fracture under AI treatment is increased by 35%-50%. In patients with prostate cancer, androgen deprivation therapy (ADT) increases bone turnover, reduces bone mass (4%-5% per year) and increases the fracture rate depending on the duration of therapy. Zoledronic acid can prevent accelerated bone loss induced by goserelin in premenopausal women, by letrozole in postmenopausal women and by ADT in men. More limited data indicate that weekly alendronate or risedronate could also be effective for preventing CTIBL. Initiation of therapy early, prior to the occurrence of severe osteoporosis, rather than after, may be more effective. Bisphosphonate treatment should be considered in osteoporotic but also in osteopenic patients if other risk factor(s) for fractures are present.

The use of bisphosphonates in cancer patients

Skeletal-related events resulting from bone metastases or osteoporosis can significantly contribute to morbidity and mortality in cancer patients. Expert opinion on the effectiveness of bisphosphonates in this setting is evolving. Here we review current evidence on the risks and benefits of bisphosphonate therapy for a wide variety of cancers, as well as clinical management of its adverse effects. A MEDLINE search of English-language literature (1966 through May 2006) was conducted using the terms bisphosphonate, cancer, multiple myeloma, malignancy, and randomized controlled clinical studies. Studies were selected based on clinical pertinence, with an emphasis on phase III clinical trials. We reviewed bibliographies for other relevant articles. Accumulating evidence reveals that bisphosphonate therapy has a significant effect in preventing skeletal complications in multiple myeloma, breast cancers, and prostate cancer, and in reducing skeletal complications in other metastatic bone malignancies. Emerging data indicate that bisphosphonates are useful for preventing bone loss resulting from cancer or its therapy. The efficacy of bisphosphonates for early-stage breast cancers remains controversial. Significant risks of bisphosphonate therapy include nephrotoxicity, electrolyte abnormalities, and osteonecrosis of the jaw. Bisphosphonate therapy has a clear role in the management of skeletal metastases associated with a variety of cancers. However, significant side effects require ongoing monitoring and treatment.

Socioeconomic and occupational risk factors for epilepsy: a nationwide epidemiological study in Sweden

OBJECTIVES

The aim of this study is to investigate associations between hospitalization for epilepsy and two factors: socioeconomic status and occupation.

DESIGN AND SETTING

A nationwide database was constructed in Sweden by linking the Swedish Census to the Hospital Discharge Register to obtain data on all first-time hospitalizations for epilepsy in adults in Sweden during the study period (1987-2004). Standardized incidence ratios (SIRs) were calculated by socioeconomic status and occupation.

RESULTS

A total of 22,638 men and 16,871 women>30 years were hospitalized for epilepsy during the study period. Low education and low income (both men and women) and being an unskilled/skilled worker (only men) was associated with slightly but significantly increased risks. Among men, increased risk was noted for waiters, launderers and dry cleaners, clerical workers, other construction workers, sales agents and drivers. Among women, increased risk was observed among cooks and stewards and administrators and managers.

CONCLUSIONS

Socioeconomic status and occupation sometimes carry significantly increased risks of hospital admission for epilepsy.

Synthesis and anticonvulsant activity of some potent 5,6-bis aryl 1,2,4-triazines

In the present research, a series of 5,6-bis aryl 1,2,4-triazines 5a~5f were synthesized by condensation of various benzils 4a~4f with aminoguanidine bicarbonate and were screened in vivo, for their anticonvulsant and neurotoxicity studies. Compounds 5a, 5b and 5d were found to be potent molecules of this series, when compared with the reference drugs phenytoin sodium, diazepam and lamotrigine. The structures of these compounds were established by IR, (1)H NMR, (13)C NMR and mass spectroscopic data.

The risk of renal impairment in hormone-refractory prostate cancer patients with bone metastases treated with zoledronic acid

BACKGROUND

Bisphosphonates have been used to treat bone metastases in hormone-refractory prostate cancer (HRPC), but certain agents have been associated with renal toxicity. For this observational study, the authors assessed the risk of renal impairment in patients with HRPC who received zoledronic acid from December 1999 to April 2005.

METHODS

A comprehensive medical records review was performed in a major tertiary oncology center (n = 122 patients). The primary outcome of renal impairment was defined as an increase >or=0.5 mg/dL or >or=1.0 mg/dL over baseline creatinine value if the baseline value was <1.4 mg/dL or >or=1.4 mg/dL, respectively. A risk factor analysis was conducted using the Andersen-Gill extension to the Cox proportional hazards model.

RESULTS

Renal impairment was observed in 23.8% of patients. The risk of renal impairment increased with an extended duration of zoledronic acid therapy (<6 months, 11.1%; >or=24 months, 26.3%) and previous pamidronate treatment (45.5% vs 19.0% for patients with no prior pamidronate). A significantly greater risk of renal impairment was associated with increasing age at zoledronic acid initiation, prior pamidronate use, and a history of renal disease, hypertension, or smoking (P <or= 0.05).

CONCLUSIONS

In an outpatient clinic setting, the risk of renal impairment among patients with HRPC who received zoledronic acid was greater than the risk reported previously in clinical trials.

The safety of zoledronic acid

Zoledronic acid has been marketed for the past 5 years for the treatment of hypercalcemia of malignancy and malignant bone disease in patients with multiple myeloma or a broad range of solid tumors. The safety profile of zoledronic acid in this patient population is well established from the databases of several large, randomized, Phase III trials and postmarketing clinical experience. Zoledronic acid is well tolerated, with predictable side effects, primarily transient flu-like symptoms, which are manageable with standard treatment. Renal monitoring is recommended, with dose reductions for patients with renal dysfunction. Monitoring for electrolyte imbalance is also important as is calcium and vitamin D supplementation. Ocular complications are rare, and osteonecrosis of the jaw is uncommon and might be avoidable with appropriate dental care.

Transgenic mice over-expressing GABA(B)R1a receptors acquire an atypical absence epilepsy-like phenotype

In this study, we tested whether over-expressing the GABA(B) receptor R1a subtype in transgenic mouse forebrain neurons would be sufficient to induce spontaneous absence seizures. As hypothesized, these transgenic mice develop spontaneous, recurrent, bilaterally synchronous, 3-6 Hz slow spike and wave discharges between 2 and 4 months of age. These discharges are blocked by ethosuximide and exacerbated by baclofen confirming their absence nature. The discharges occur coincident with absence-like behaviors such as staring, facial myoclonus, and whisker twitching. However, in contrast to typical absence epilepsy models, these mice move during the ictal event, display spike and wave discharges in both thalamocortical and limbic circuitry, exhibit impaired hippocampal synaptic plasticity, and display significantly impaired learning ability. Collectively, these features are more characteristic of the less common but more debilitating atypical form of absence epilepsy. Thus, these data support a role for the GABA(B)R1a receptor subtype in the etiology of atypical absence epilepsy.

Rat epileptic seizures evoked by BmK αIV and its possible mechanisms involved in sodium channels

This study showed that rat unilateral intracerebroventricular injection of BmK alphaIV, a sodium channel modulator derived from scorpion Buthus martensi Karsch, induced clusters of spikes, epileptic discharges and convulsion-related behavioral changes. BmK alphaIV potently promoted the release of endogenous glutamate from rat cerebrocortical synaptosomes. In vitro examination of the effect of BmK alphaIV on intrasynaptosomal free calcium concentration [Ca(2+)](i) and sodium concentration [Na(+)](i) revealed that BmK alphaIV-evoked glutamate release from synaptosomes was associated with an increase in Ca(2+) and Na(+) influx. Moreover, BmK alphaIV-mediated glutamate release and ion influx was completely blocked by tetrodotoxin, a blocker of sodium channel. Together, these results suggest that the induction of BmK alphaIV-evoked epileptic seizures may be involved in the modulation of BmK alphaIV on tetrodotoxin-sensitive sodium channels located on the nerve terminal, which subsequently enhances the Ca(2+) influx to cause an increase of glutamate release. These findings may provide some insight regarding the mechanism of neuronal action of BmK alphaIV in the central nervous system for understanding epileptogenesis involved in sodium channels.

Various pharmacogenetic aspects of antiepileptic drug therapy: a review

Pharmacogenetics concerns the influence of an individual's genetic background on the pharmacokinetics and pharmacodynamics of xenobiotics. Much of the pharmacogenetic data in the field of epilepsy deals with the pharmacokinetics of antiepileptic drugs (AEDs). In particular, two polymorphisms of cytochrome P450 2C9 are known to slow down the metabolism of phenytoin to a degree that increases the risk of the neurotoxic adverse effects of this drug among carriers of these polymorphisms. A significant number of patients with epilepsy do not respond to AEDs and such pharmacoresistance is a major, largely unsolved, problem that is likely to be multifactorial in nature. In this regard, genetic factors may influence transmembrane drug transporter proteins, thereby modifying the intracerebral penetration of AEDs. Monogenic idiopathic epilepsies are rare and frequently associated with ion channel mutations; however, to date, a consistent relationship between changes in channel properties and clinical phenotype has not been established nor has any association between genotype and response to specific treatment options. Polymorphisms of drug targets may represent another genetic facet in epilepsy: a recent study demonstrated for the first time a polymorphism of a drug target (the alpha-subunit of a voltage-gated sodium channel) associated in clinical practice with differing response to two classic AEDs. Adverse drug reactions and teratogenicity of AEDs remain a major concern. Whole-genome single nucleotide polymorphism profiling might in the future help to determine genetic predisposing factors for adverse drug reactions. Recently, in Han Chinese treated with carbamazepine and presenting with Stevens-Johnson syndrome, a strong association was found with HLA B*1502. If genetically targeted drug development becomes more affordable/cost efficient in the near future, the development of new drugs for relatively rare diseases could become economically viable for the pharmaceutical industry. The synergy of lower trial costs and efficacy-based prescribing may reduce the cost of medical treatment for a particular disease. This hypothetical advantage of the practical use of pharmacogenetics is, however, counterbalanced by several possible dangers, including illicit data mining and the development of a human 'genetic underclass' with the risk of exclusion from, for example employment or health insurance, because of an 'unfavourable' genetic profile.

Epilepsy: public knowledge and attitude in a slum area of Karachi, Pakistan

BACKGROUND

Epilepsy is a common but widely misunderstood illness. Consequently, epileptics suffer from considerable stigmatization in society. Since no studies have detailed the misperceptions about epilepsy in our community, it is not possible to provide focused intervention aimed at eliminating this prejudice.

PURPOSE

To assess the knowledge and attitude regarding epilepsy in an adult population of a Karachi slum area.

METHODS

A face-to-face interview was conducted on 487 consenting adult non-epileptics (305 males; 182 females) who were conveniently sampled. Chi-square test was employed to calculate the variability in knowledge and attitude with demographic and other variables.

RESULTS

In all, 12.5% had never heard about epilepsy. Among the rest, 66.7% identified epilepsy as being non-infectious, while 28.2% were unaware of any treatment available for it. Among the other 71.8%, 62.7% were aware of the existence of anti-epileptic drugs. Religious/spiritual treatment was chosen as the most effective treatment by 33.1%. Males were more likely to identify epilepsy as being non-infectious (p=0.02). Nearly 18% of the respondents would not object to their child marrying an epileptic, 69.5% did not want to socially isolate the epileptics, 83.1% said epileptics could receive academic education, 85.6% said they could perform activities of daily life and 62.4% said they could become useful members of the society. Those who considered epilepsy to be infectious were more likely to carry negative attitudes towards epilepsy (p<0.01 with four attitudes).

CONCLUSIONS

Considerable gaps exist in the community's knowledge about epilepsy. Some of these may explain the prevalence of negative attitudes towards this ailment.

Zoledronic acid in the management of metastatic bone disease

Bisphosphonate therapy has become a standard of therapy for patients with malignant bone disease. Moreover, in vivo preclinical and preliminary clinical data suggest that bisphosphonates may prevent cancer treatment-induced bone loss and the onset of malignant bone disease in patients with early-stage cancer. This comprehensive review critically reports the several preclinical evidences of action of bisphosphonates on osteoclasts, lymphocytes and tumour cells. In addition, all the clinical trials evaluating the effects of principal bisphosphonates on skeletal disease progression in patients with breast cancer, prostate cancer, non-small cell lung cancer and other cancers have been reported. Of the available bisphosphonates, intravenous zoledronic acid has demonstrated the broadest clinical activity and is actually approved for the treatment of bone metastases from any solid tumour in many countries. Renal safety is an important consideration for oncologists who are treating patients with bisphosphonates. This issue and the other topics relating to the safety of bisphosphonates are discussed in this review.

Temporal ontogeny of circuit activation prior to the onset of seizure susceptibility in EL/Suz mice

The EL/Suz (EL) mouse is a model of multifactorial temporal lobe epilepsy in which seizures begin around 90 days of age, but can be hastened through increased exposure to human handling. In order to better understand seizure etiology in this mouse strain relative to seizure-resistant control mice, the present study examined region-specific neuronal activation in response to non-seizure-inducing handling implemented before the onset of seizure susceptibility. Immediate-early gene (cFos) expression emerged in EL mice by postnatal day (PND) 21 in the primary motor cortex, progressed to the locus ceruleus and prefrontal cortex by PND 35, and appeared in the hippocampus and amygdala by PND 70, as mice neared the age of onset for seizure susceptibility. Thus, mirroring the pattern observed during the course of a seizure, specific brain regions were differentially recruited to a neural network for seizure predisposition before the onset of seizure susceptibility. This developmental pattern of early and transient neural activation represents an important window for the study of causal mechanisms of seizure susceptibility following exposure to environmental triggers.

Postterm delivery and risk for epilepsy in childhood

OBJECTIVE

Postterm delivery is a risk factor for perinatal complications, some of which increase risk for neurologic morbidity. We aimed to examine the association between postterm delivery and risk for epilepsy in childhood.

METHODS

We conducted a cohort study of singleton children who were born in 3 Danish counties from 1980 to 2001. Birth registry data were linked with hospital records to identify cases of epilepsy in the first 12 years of life. We included children who were born at > or = 39 gestational weeks and computed crude, age-specific, and birth weight standardized incidence rates of epilepsy. We estimated adjusted incidence rate ratios according to mode of delivery by Poisson regression.

RESULTS

Among the 277,435 nonpreterm births, 32,557 were at > or = 42 weeks, including 3396 at > or = 43 weeks. Nearly one fourth of the 2805 epilepsy cases occurred in the first year of life. In that period, birth weight standardized incidence rate ratios for epilepsy were 1.3 for birth at 42 weeks and 2.0 for birth at > or = 43 weeks, compared with birth at 39 to 41 weeks. Among children who were delivered by cesarean section, incidence rate ratios adjusted for birth weight, presentation, malformations, and county were 1.4 for birth at 42 completed weeks and 4.9 for birth at > or = 43 weeks, compared with term vaginal births. There was a similar tendency among children who were delivered with the assistance of instruments. We found no evidence for the association between postterm delivery and risk for epilepsy beyond the first year of life.

CONCLUSIONS

Prolonged gestation is a risk factor for early epilepsy; the added increase in risk for instrument-assisted and cesarean deliveries could be attributable to factors that are related to both birth complications and epilepsy.

Differential roles of NR2A- and NR2B-containing NMDA receptors in activity-dependent brain-derived neurotrophic factor gene regulation and limbic epileptogenesis

Fleeting activation of NMDA receptors (NMDARs) induces long-term modification of synaptic connections and refinement of neuronal circuits, which may underlie learning and memory and contribute to pathogenesis of a diversity of neurological diseases, including epilepsy. Here, we found that NR2A and NR2B subunit-containing NMDARs were coupled to distinct intracellular signaling, resulting in differential BDNF expression and extracellular signal-regulated kinase 1/2 (ERK1/2) activation. Selective activation of NR2A-containing NMDARs increased BDNF gene expression. Activation of NR2B-containing NMDARs led to ERK1/2 phosphorylation. Furthermore, selectively blocking NR2A-containing NMDARs impaired epileptogenesis and the development of mossy fiber sprouting in the kindling and pilocarpine rat models of limbic epilepsy, whereas inhibiting NR2B-containing NMDARs had no effects in epileptogenesis and mossy fiber sprouting. Interestingly, blocking either NR2A- or NR2B-containing NMDARs decreased status epilepticus-induced neuronal cell death. The specific requirement of NR2A and its downstream signaling for epileptogenesis implicates attractive new targets for the development of drugs that prevent epilepsy in patients with brain injury.

Therapy insight: the risks and benefits of bisphosphonates for the treatment of tumor-induced bone disease

Bisphosphonates are a valuable class of drugs with potent anti-resorptive actions that make them ideal for skeletal protection in osteoporosis, cancer bone metastasis, multiple myeloma, and Paget's disease of bone. It has become apparent, however, that these drugs also have the potential to cause a number of adverse effects. While these do not limit bisphosphonate use, the incidence of these adverse events can be minimized if appropriate care is taken with their administration, and by maintaining appropriate surveillance and patient care. We review the range of adverse reactions to bisphosphonate therapy with a particular emphasis on the recently identified association between long-term bisphosphonate treatment and osteonecrosis of the jaw. This is a potentially serious side effect seen mostly in patients with multiple myeloma or breast cancer bone metastases who receive intravenous bisphosphonate treatment. While the etiology is uncertain, a strong association with dental pathology and interventions highlights the need for close attention to dental health in this patient group.

Oxidative stress markers in surgically treated patients with refractory epilepsy

OBJECTIVES

This study examines the redox status of drug-resistant epileptic patients and how it is modified after surgical treatment.

DESIGN AND METHODS

The activity of antioxidant enzymes (superoxide dismutase, catalase and glutathione peroxidase), and markers of damage to biomolecules (malondialdehyde and advanced oxidation protein products) were determined by spectrophotometric methods in the serum of 9 drug-resistant epileptic patients, before and at different times after surgery, and in 32 control subjects.

RESULTS

Pre-surgery, epileptic patients presented increases in markers of oxidative damage and alterations in the activities of antioxidant enzymes. Additionally, patients showed a correlation between advanced oxidation protein products and the evolution time of the illness. After surgery, patients showed a trend to normalization in all the measured variables, except for the superoxide dismutase activity.

CONCLUSIONS

Drug-resistant temporal lobe epilepsy is associated with an oxidative stress condition that is favourably modified by the surgical resection of the epileptic foci.

Advances in the management of corticosteroid-induced osteoporosis with bisphosphonates

Corticosteroids are widely used as anti-inflammatory and immunosuppressive agents to treat a variety of chronic conditions. Long-term (>1 year) corticosteroid use can lead to bone loss, and therefore, osteopenia or osteoporosis. Corticosteroid-induced osteoporosis (CIO) leads to increased bone fragility and subsequently fractures, which, in turn, lead to a loss of physical, emotional and social health for the patient and increased costs for healthcare providers. A wealth of data exists demonstrating the efficacy of the oral bisphosphonates, etidronate, alendronate and risedronate in increasing bone mineral density in patients with CIO or preventing bone loss in patients commencing corticosteroid therapy. Data regarding fracture prevention are less clear, as statistically significant reductions in the incidence of fractures have only been reported for patient subgroups or meta-analyses. However, many treatment guidelines recommend the use of oral bisphosphonates for the prevention and treatment of CIO. These guidelines are, however, not reflected in prescribing practice, and the majority of patients do not receive adequate concomitant therapy. This review summarizes the available data for bisphosphonates in CIO. Therapeutic adherence with oral bisphosphonates is an issue, with approximately 50% of patients discontinuing therapy within the first year. The primary reasons for this are poor gastrointestinal tolerability and the frequency with which complex dosing requirements must be followed. The inconvenience of taking daily or weekly bisphosphonate therapy is of particular importance in patients with CIO who may be regularly taking several other medications. Data obtained in studies with ibandronate indicate that bisphosphonate administration by rapid intravenous injection provides an effective, well-tolerated and practical alternative to current oral regimens in the management of patients with CIO.

Pediatric posttraumatic seizures: epidemiology, putative mechanisms of epileptogenesis and promising investigational progress

Posttraumatic seizures and epilepsy are common in children experiencing traumatic brain injury and portend worse functional outcome. Unfortunately, the pathogenesis of pediatric posttraumatic seizures and epilepsy remains poorly understood, and no efficacious preventive therapy for post-traumatic epilepsy has been identified. This article reviews the epidemiology of pediatric posttraumatic seizures, discusses prominent putative mechanisms of posttraumatic epileptogenesis and highlights recent promising progress in experimental investigations of posttraumatic seizures and epilepsy.

Ibandronate for the treatment of hypercalcemia or nephrocalcinosis in patients with multiple myeloma and acute renal failure: Case reports

Multiple myeloma disrupts calcium homeostasis by a variety of mechanisms, including bone destruction and resorption. This causes hypercalcemia. When left untreated, hypercalcemia leads to nephrocalcinosis, impairment of kidney function, and eventually renal failure. Some degree of renal dysfunction is common in myeloma patients. Here, we report case studies showing the efficacy and renal safety of the single-nitrogen bisphosphonate, ibandronate, for the treatment of hypercalcemia and/or nephrocalcinosis in multiple myeloma patients hospitalized with acute renal failure. Patients (n = 7) received either one or two intravenous infusions of ibandronate (2-6 mg). Ibandronate was well tolerated in all patients and returned elevated blood calcium levels to normal. Renal function improved for all patients and normalized in 3/7 patients. We conclude that ibandronate is involved in rapidly improving or restoring acute renal function and calcium levels to within the normal range in this patient population. To clarify the exact value of ibandronate, further investigation is warranted in randomized prospective trials.

Protein C, protein S and other pro- and anticoagulant activities among epileptic children using sodium valproate

This study was conducted to evaluate some anticoagulants' (protein C, protein S and antithrombin) activities among epileptic children treated with VPA and to learn if thromboembolic events occur among these children or their parents. Twenty-five boys and 15 girls using VPA for at least 3 months were included in the VPA group. The control group consisted of 28 boys and 12 girls who had no infection and did not use any medication that could alter protein C activity. Complete blood counts, ALT, AST, PT, aPTT, fibrinogen, protein C, protein S and AT tests were studied in both groups. Serum VPA levels were determined in the VPA group. Protein C and protein S activities of the children in the VPA group were significantly lower than those in the control group (89.5+/-19.3% vs 104.9+/-21.7% and 44.6+/-16.3% vs 59.4+/-28.4%, respectively). Neither children using VPA, nor their parents had any thromboembolic events in medical history. Platelet counts, ALT and fibrinogen levels in the VPA group were significantly lower than those in the controls. A negative correlation was found between serum VPA level and platelet counts. There were also negative correlations between fibrinogen and serum VPA levels, and between fibrinogen level and protein S activity. The children in the VPA group had lower PT and higher aPTT levels than the children in the control group. Since other factors known to alter the anticoagulant activities and liver functions were eliminated initially, the decreases of protein C and protein S activities, thrombocyte counts, ALT, PT and fibrinogen levels and increase in aPTT level may be attributed to VPA. VPA hepatotoxicity can be the cause of decreased pro- and anticoagulant activities.

Familial Risks for Epilepsy among Siblings Based on Hospitalizations in Sweden

PURPOSE

Epilepsy is a common disabling condition, with high heritability according to twin studies. Characterization of familial risks for common subtypes of epilepsy will advance the search for the heritable causes of these conditions and their underlying mechanisms. We aim at defining familial risks for siblings to be hospitalized because of epilepsy.

METHODS

A nationwide ad hoc epilepsy database was constructed by linking the Multigeneration Register on 0- to 69-year-old siblings to the Hospital Discharge Register for data on epilepsies covering the years 1987-2001. Standardized risk ratios (SIRs) were calculated for affected sibling pairs by comparing them to those whose siblings had no epilepsy.

RESULTS

Among a total of 26,799 hospitalized cases, 598 affected siblings were identified with a familial SIR of 2.35; the SIR was highest at ages 0-4 years (6.82). Infantile spasms showed the highest risk for any subtype (10.45), when a co-sibling was diagnosed with any epilepsy. When both siblings were diagnosed with a concordant (same) subtype of epilepsy, the SIRs were high, i.e. 8.43 for generalized idiopathic epilepsy, 2.56 for partial epilepsy, 24.72 for status epilepticus and 24.39 for other epilepsies. Generalized idiopathic epilepsy was also associated with grand mal (4.06) and other epilepsies (7.61). The numbers of cases were small but concordant diagnoses always showing higher SIRs compared with discordant diagnoses.

CONCLUSIONS

Within the limits of the present sample size, our results suggest high familial aggregation for certain subtypes of epilepsy for which distinct genetic mechanisms may underlie.

Synthesis and anticonvulsant activity of new N-1′,N-3′-disubstituted-2′H,3H,5′H-spiro-(2-benzofuran-1,4′-imidazolidine)-2′,3,5′-triones

Thirteen new N-1',N-3'-disubstituted-2'H,3H,5'H-spiro-(2-benzofuran-1,4'-imidazolidine)-2',3,5'-triones were synthesized and their pharmacological activity determined with the objective to better understand their SAR for anticonvulsant activity. The anticonvulsant effects of these compounds were evaluated by standard pentylenetetrazol (scPTZ test) and maximum electroshock seizure (MES test) models in mice. Most of the compounds showed ability to protect against the pentylenetetrazol-induced convulsions. Compound 3o (the N-1'-p-nitrophenyl, N-3'-ethyl derivative) in the N-1'-aryl, N-3'-alkyl disubstituted series exhibited maximum activity with ED(50) of 41.8 mg/kg in scPTZ convulsion model.

Epilepsy: a review of selected clinical syndromes and advances in basic science

Epilepsy is a common neurologic disorder that manifests in diverse ways. There are numerous seizure types and numerous mechanisms by which the brain generates seizures. The two hallmarks of seizure generation are hyperexcitability of neurons and hypersynchrony of neural circuits. A large variety of mechanisms alters the balance between excitation and inhibition to predispose a local or widespread region of the brain to hyperexcitability and hypersynchrony. This review discusses five clinical syndromes that have seizures as a prominent manifestation. These five syndromes differ markedly in their etiologies and clinical features, and were selected for discussion because the seizures are generated at a different 'level' of neural dysfunction in each case: (1) mutation of a specific family of ion (potassium) channels in benign familial neonatal convulsions; (2) deficiency of the protein that transports glucose into the CNS in Glut-1 deficiency; (3) aberrantly formed local neural circuits in focal cortical dysplasia; (4) synaptic reorganization of limbic circuitry in temporal lobe epilepsy; and (5) abnormal thalamocortical circuit function in childhood absence epilepsy. Despite this diversity of clinical phenotype and mechanism, these syndromes are informative as to how pathophysiological processes converge to produce brain hyperexcitability and seizures.