Outcome and complications of chronically implanted subdural electrodes for the treatment of medically resistant epilepsy.

BACKGROUND: Surgery for medically resistant epilepsy is safe and effective. However, when noninvasive techniques are insufficient, then consideration is given to invasive electrocorticography (EcoG). OBJECTIVE: The aim of the study was to analyze results and complications of subdural electrodes placement in the treatment of intractable epilepsy. METHODS: Ninety-one consecutive patients who underwent placement of subdural electrodes (1999-2010) were considered for this study. All patients underwent a standardized pre-operative evaluation. Invasive subdural electrode placement was considered when there were inadequate ictal recordings, there was discordance between EEG and neuroimaging or the epileptogenic zone was localized near eloquent cortex. RESULTS: Resective epilepsy surgery was performed in 70/91 patients (76.9%). Twenty-four out of seventy (34.3%) who underwent surgical resection were seizure-free (CL-I) at last follow-up. A statistical evaluation revealed a very strong trend for patients with positive lesional pre-operative MRI to have improved outcomes compared to normal brain MRI population (p=.028). There were 10 surgical related complications (11%), but no mortality or permanent morbidity. Statistical analysis demonstrated that placement of a subdural grid in any combination was statistically significant (p=.01) for surgical complications. CONCLUSIONS: Invasive monitoring is a useful and necessary technique for the surgical treatment of intractable epilepsy. Careful surveillance is required during the monitoring period especially when the patient has undergone large subdural grid placement. A good working hypothesis can minimize complications and achieve better outcomes.

Clinical presentation, risk factors and treatment outcomes of first allograft rejection after penetrating keratoplasty in early and late postoperative period.

PURPOSE: Corneal graft rejection is the most common reason for the failure of an allograft corneal transplant. We undertook this study to identify and compare risk factors and treatment outcomes for early and late corneal graft rejections after optical penetrating keratoplasty. METHODS: A retrospective case file analysis of 880 primary penetrating keratoplasties was performed at a tertiary ophthalmic care centre. Patients were divided into early rejectors (rejection episode within 6 months postoperatively) and late rejectors (rejection episode after 6 months postoperatively). Main parameters evaluated were demographics, preoperative diagnosis and clinical signs, donor tissue details, surgical technique, details of rejection episode, treatment, and outcome information. RESULTS: A total of 156 patients with rejection episodes were identified. Of these, 42 (26.9%) patients experienced early rejection episodes and 114 (73.1%) patients experienced late rejection episodes. Preoperative donor and recipient characteristics, surgical technique, and clinical presentation of graft rejection were found to be similar between both groups after a Bonferroni correction was applied (P>0.005). Treatment outcomes of graft rejections were not significantly different (P=0.46) between early and late rejectors, with 83% of patients responding to rejection treatment (80% early rejectors; 85% late rejectors). CONCLUSION: Patients with early and late graft rejection have similar characteristics and both groups respond to treatment equally.

The occurrence of arterio-venous fistula during lower limb subintimal angioplasty: treatment and outcome.

OBJECTIVES: To describe our experience with iatrogenic arterio-venous fistula (AVF) occurring during lower limb subintimal angioplasty, their management and the final clinical, radiological outcome. DESIGN: Retrospective review of case series from two centres, from a computerised database over a period of five years. MATERIAL: Twelve patients whose lower limb subintimal angioplasty was complicated by Iatrogenic AVF. RESULTS: The Majority of AVF occurred at the popliteal trifurcation vessels. And the incidence of this complication in our case series was 0.8%. This was managed with a variety of techniques-Coil embolisation, balloon tamponade, alternative dissection and stent placement. In one patient, the fistula was left open intentionally. All twelve patients had a successful angioplasty. The overall technical success rate for AVF ablation was eighty percent. CONCLUSIONS: AVF is a potential complication of angioplasty. The majority can be managed by endovascular means during the angioplasty procedure with good technical success.

Activation of NF-kappaB in the mouse spinal cord following sciatic nerve transection.

NF-kappaB is a ubiquitous nuclear transcription factor that regulates a number of physiological processes. NF-kappaB activity has been implicated in enhancing neuronal survival following CNS injury. The present study was conducted to test the hypothesis that NF-kappaB activity is up-regulated in neurons of the spinal cord in response to peripheral nerve transection. In this series of experiments, we used NF-kappaB reporter mice in which activation of NF-kappaB drives the expression of the lac-z gene. The response to injury of cells in the spinal cord was assessed by evaluating the number and distribution of beta-galalactosidase (beta-gal)-positive cells following sciatic nerve transection. The animals were randomly assigned to four groups, which were allowed to survive for one, three, five and ten days. Four mice that did not undergo sciatic nerve transection were assigned to each group to serve as controls. The total number of beta-gal-positive cells in the right and left dorsal and ventral horns were compared. The numbers of beta-gal-positive cells between the right and left sides were significantly different three and five days post axotomy (p<0.05). Double immunofluorescent labeling was utilized to characterize which cells showed NF-kappaB activity, and it revealed that all beta-gal-positive cells were colocalized with MAP-2-positive neurons. The results of this study demonstrated that complete sciatic nerve transection leads to an up-regulation of NF-kappaB transactivation in spinal neurons ipsilateral to the side of transection. The increase in activity in the ipsilateral dorsal horn is consistent with this transcription factor acting as neuronal survival signal during this time frame in response to the peripheral nerve insult.

Effects of early visual experience and diurnal rhythms on BDNF mRNA and protein levels in the visual system, hippocampus, and cerebellum.

The expression of brain-derived neurotrophic factor (BDNF) mRNA and the secretion of BDNF protein are tightly regulated by neuronal activity. Thus, BDNF has been proposed as a mediator of activity-dependent neural plasticity. Previous studies showed that dark rearing (DR) reduces BDNF mRNA levels in the primary visual cortex (V1), but the effects of visual experience on BDNF protein levels are unknown. We report that rearing in constant light or DR alters BDNF mRNA and protein levels in the retina, superior colliculus (SC), V1, hippocampus (HIPP), and cerebellum (CBL), although the changes in mRNA and protein are not always correlated. Most notably, DR increases BDNF protein levels in V1 although BDNF mRNA is decreased. BDNF protein levels also undergo diurnal changes. In the retina, V1, and SC, BDNF protein levels are higher during the light phase of the circadian cycle than during the dark phase. By contrast, in HIPP and CBL, the tissue concentration of BDNF protein is higher during the dark phase. The discrepancies between the experience-dependent changes in BDNF mRNA and protein suggest that via its effects on neuronal activity, early sensory experience alters the trafficking, as well as the synthesis, of BDNF protein. The circadian changes in BDNF protein suggest that BDNF could cause the diurnal modulation of synaptic efficacy in some neural circuits. The fluctuations in BDNF levels in nonvisual structures suggest a potential role of BDNF in mediating plasticity induced by hormones or motor activity.

Patient knowledge concerning their referral to a restorative dental unit in a community clinic: a pilot study.

One hundred patients referred to a Community Dental Service completed a questionnaire, the purpose of which was to find out why they perceived they had been referred and to whom they thought they had been referred. The results showed that most patients (64) perceived they would see a Specialist rather than a Consultant and most (63) thought they had been referred because their dentist could not treat their problem. There was no significant relationship between age and to whom the patient thought they had been referred, and further analysis to estimate the effect of age, gender and length of time with the current dentist or the reasons for referral failed to show any significant relationships.

Neuregulin is a mitogen and survival factor for olfactory bulb ensheathing cells and an isoform is produced by astrocytes.

The rat olfactory bulb is an exceptional CNS tissue. Unlike other areas of the brain, growing axons are able to enter the olfactory bulb and extend within this CNS environment throughout adult life. It appears that the glial cells of the olfactory system, known as olfactory bulb ensheathing cells (OBECs), may have an important role in this remarkable process of CNS neural regeneration. OBECs are unusual glial cells, possessing properties of both astrocytes and Schwann cells. In this study we show that astrocytes (in the form of astrocyte-conditioned medium; ACM) produce two critical regulatory functions for OBECs: mitogenic activity and a survival factor. Interestingly, the ACM-derived activity for OBECs appears to reside in a signalling protein(s) belonging to the neuregulin (NRG) family of growth factors, and specifically appears to coincide with one or more products of the nrg-1 gene. Our observations provide evidence for the following: recombinant human neu differentiation factors (NDFbeta1, -2 and -3) are mitogenic to OBECs; the activity in ACM can be neutralized by NDF antibodies; these same antibodies detect a 50-kDa, non-heparin binding protein in concentrated ACM; astrocytes express detectable nrg-1 transcripts; and OBECs express functional NRG receptors erbB2 and erbB4.

Expression of the dm-20 isoform of the plp gene in olfactory nerve ensheathing cells: evidence from developmental studies.

The olfactory bulb is a specialized area of the CNS with well-defined areas containing both myelinated, and non-myelinated axons. The presence of plp gene transcripts has been demonstrated previously in the olfactory bulb, but no detailed description of plp gene activity in this complex area of the CNS is available. In this study we describe the developmental expression of the two plp gene isoforms, plp and dm-20, and their products in the mouse olfactory bulb. plp gene activity was present in the non-myelinated olfactory nerve layer of the bulb from E14 through to adult ages. Expression in the deeper layers of the bulb, associated with myelination of the second order axons, was apparent from P10 onwards. dm-20 was the predominant isoform expressed at the transcript level in the olfactory nerve layer and was the only isoprotein demonstrable by immunostaining. This expression was associated with the resident glial cell of the non-myelinated olfactory nerve layer, the olfactory nerve ensheathing cell. Selective expression of the DM-20 isoprotein in the non-myelin forming olfactory nerve ensheathing cells implies a role for DM-20 other than as a structural myelin protein. Further study of this specialized glial cell may prove useful in elucidating the specific functions(s) of the DM-20 isoprotein.

Hypoglycemia manifested by sinus bradycardia: a report of three cases.

Three cases are reported of hypoglycemia manifested by profound sinus bradycardia and fatigue, which responded to i.v. dextrose with prompt normalization of the cardiac rhythm. The cases involved 3 different patients and disease processes: a young female who had anorexia nervosa and profound malnutrition; an elderly, nondiabetic male who subsequently experienced a transient ischemic attack: and a patient who had diabetes mellitus managed with chronic, subcutaneous insulin administration. It is vitally important that the emergency physician recognize unusual clinical manifestations of hypoglycemia and fully evaluate such scenarios when hypoglycemia may occur. Untreated, hypoglycemia may result in significant chronic morbidity, and rarely, in death. Bradyarrhythmias--particularly sinus bradycardia--should be added to the list of potential clinical manifestations of hypoglycemia.

Case report: the use of a resin retained bridge with movable joint.

The use of resin retained bridge work is commonplace within dental practice. Factors that may affect long term success include the type of metal used and surface preparation, the resin, operator technique, the surface area of the tooth, differing movement of the abutment teeth and occlusal forces. A clinical case is reported in which a resin retained bridge with a movable joint was used to restore missing anterior teeth in a 15 year old girl with a developing occlusion.

Economic consequences of marital dissolution for blacks.

Paying particular attention to the economic impact of post-divorce on black survey respondents of both sexes, "this study analyzes Weitzman's suggestion that men and women lose economic well-being in the first year after divorce. Family incomes of divorced women and men are compared with [those of] their married counterparts for five SES [socioeconomic status] categories. Using t-tests, it was found that, for most categories, for both genders, incomes of divorced persons were lower than incomes of married persons. Family incomes were regressed against a set of four control variables and a marital status variable. The marital status variable was statistically significant for four of the five SES categories for females. This was not true for males. Policy implications are considered." The geographical focus is on the United States.

Excimer laser lamellar keratoplasty.

PURPOSE: To evaluate a procedure using the excimer laser to perform lamellar keratoplasty to treat deep corneal scars in the central optical zone. To determine if excimer laser can safely prepare a smooth surface for the host bed and the donor button, assess the interface opacity and evaluate the effects of the ablation on the recipient's endothelial surface with the deeper ablation. METHODS: Nineteen rabbits underwent an excimer laser lamellar keratoplasty in one eye. The rabbits were followed for 9 to 12 weeks until they were sacrificed. RESULTS: Little opacity developed at the graft-host interface and scanning electron microscopy of the endothelial surface showed little difference between the treated and untreated areas or the endothelium of the untreated eyes. CONCLUSIONS: Our results suggest that the use of the excimer laser to treat corneas with deep stromal scars and normal endothelium is feasible. However, we have not proved that this technique will give a better result than conventional lamellar dissection methods.

A 25.7 x 10(3) M(r) hydra metalloproteinase (HMP1), a member of the astacin family, localizes to the extracellular matrix of Hydra vulgaris in a head-specific manner and has a developmental function.

Hydra extracellular matrix (ECM) is composed of a number of components seen in vertebrate ECM such as laminin, type IV collagen, fibronectin, and heparan sulfate proteoglycan. A number of functional studies have shown that hydra ECM plays an important role in pattern formation and morphogenesis of this simple metazoan. The present study was designed to identify matrix degrading proteinases in hydra and determine their potential function in hydra morphogenesis. Using SDS-PAGE gelatin-zymography, five gelatinolytic bands were identified with relative molecular masses of 67 x 10(3), 51-58 x 10(3) (a triplet) and 25-29 x 10(3), respectively. Inhibition studies indicated that all of these gelatinases were metalloproteinases. Gelatin-zymography indicated that there was a differential distribution of these gelatinases along the longitudinal axis of hydra, with the 67 x 10(3) M(r) gelatinase being concentrated in the body column, while the 51-58 x 10(3) M(r) gelatinase triplet and the 25-29 x 10(3) M(r) gelatinase concentrated in the head region. Purification procedures were successfully developed for the 25-29 x 10(3) M(r) metalloproteinase which has been termed hydra metalloproteinase 1 (HMP1) and which appeared as a single band with a SDS-PAGE mobility of 25.7 x 10(3) M(r). The N-terminal sequence of purified HMP1 indicated that it has structural homology with metalloproteinases that belong to the astacin family. Subsequent cloning and sequencing of cDNA clones confirmed the identification of HMP1 as an astacin-like metalloproteinase. Immunocytochemical studies with antibodies generated against the purified enzyme and to a synthetic peptide indicated that HMP1 was localized to the ECM of tentacles. Functional studies were performed in which purified HMP1, anti-HMP1 IgG, or suspected substrates of HMP1 (e.g. growth factors such as TGF-beta 1) were introduced into the interepithelial compartment of hydra using a 'DMSO loading' procedure. These studies indicated that HMP1 has a functional role during a number of developmental processes such as head regeneration and cell differentiation/transdifferentiation of tentacle battery cells.

A single purification procedure for the major resident proteins of the ER lumen: endoplasmin, BiP, calreticulin and protein disulfide isomerase.

We have developed a single purification procedure for the four major resident endoplasmic reticulum (ER) proteins: protein disulfide isomerase (PDI), BiP, endoplasmin, and calreticulin. Three of these proteins are thought to play a role in protein folding in vivo, whereas calreticulin is thought to be the major calcium binding protein in the ER. The proteins were purified from fresh bovine liver by taking advantage of individual characteristics of the proteins. Liver microsomes were prepared and then premeabilized to release the lumenal contents. After ammonium sulfate precipitation, the proteins were purified by chromatography; BiP was purified by affinity chromatography on ATP-agarose, and both endoplasmin and calreticulin were purified by affinity chromatography on Con A-Sepharose. PDI was purified by anionic ion exchange chromatography.

The ambivalence of the maternal body: psychoanalytic readings of the legend of Van Gogh.

This article aims to identify the collective social investment in 'Van Gogh' as a cultural icon, and to ask what function his life story, colourfully illustrated by his art work, has performed in the West since the 1890s. It argues that the life and work of a Dutch artist have become the raw materials for a series of secular 'mystery' plays and christological psychodramas that reflect the ills of twentieth-century experience. The key moments when Van Gogh was made into a figure in a popular imagination were psychologically significant: the Depression and the immediate aftermath of World War II. 'Van Gogh', a fantasy figure of modern man, has been over-'psychologised', his work becoming only the testament to the myth of modern man. Using social-art-historical techniques, the author tries to distance this kind of reading in the case of one drawing of a peasant woman, bending over. Situating the fantasy that the drawing services in precise social and historical terms of bourgeois men formed in childhood in relation to a split feminine/maternal figure of the lady/mother and the working-class nursemaid, the article examines how to use psychoanalysis to read the formal oddities of the work--distortion and monumentality, attention to a fragmented, eroticised but also punished body--for the oscillation between pre-oedipal fantasies of maternal plenitude and awe and oedipal anxieties which sadistically inflict humiliation on the maternal body. Finally, instead of producing Van Gogh as the extreme case of an 'other', the author recognises the drawing as a space where present fantasies of the reader encounter those of the producer. Psychoanalysis informing historically-precise interpretation becomes a demythologising hermeneutic.

Effects of S-dobutamine on ischemic myocardium caused by coronary artery narrowing.

Cardiovascular effects of S-dobutamine were compared with effects of vehicle and other catecholamines in dogs during and after 3 days of approximately 90% ligation of the left anterior descending coronary artery (LAD). Twenty-four hours after LAD ligation, dogs infused with S-dobutamine (2.5 micrograms/kg/min intravenously, i.v.) maintained systolic blood pressure (SBP 149 +/- 6 mm Hg), diastolic blood pressure (DBP 100 +/- 6 mm Hg), and aortic dP/dt60 (2.8 +/- 0.2 s-1), with no significant changes from preligation values. In comparison, saline-treated dogs showed decreases in arterial BP and contractility: SBP 121 +/- 4 mm Hg; DBP 85 +/- 3 mm Hg; and aortic dP/dt60 was 1.9 +/- 0.1 s-1. S-Dobutamine-infused dogs had a heart rate (HR) of 148 +/- 5 beats/min with 44 +/- 14 beats/min premature ventricular contractions (PVCs), whereas dogs infused with saline, R-dobutamine, dopamine, norepinephrine (NE), or isoproterenol (ISO) all displayed a significantly greater number of PVCs at 24 h. Myocardial necrosis was limited by S-dobutamine treatment (2.5 micrograms/kg/min i.v. for 54 h). As demonstrated by histologic examination, S-dobutamine ameliorated the effects of ischemia as compared with vehicle, R-dobutamine, dopamine, hexamethonium, NE, or ISO. Myocardial tissue electrolytes, quantified 72 h after LAD ligation, were maintained by S-dobutamine-infused dogs in all sections of left ventricle (LV); but in saline-treated dogs, Ca2+ increased eightfold, Na+ increased twofold, and both K+ and Mg2+ decreased 50% in tissue "at risk" as compared with tissues "not at risk." Coronary nutrient blood flow (CNBF) to myocardial capillary vessels was calculated by radiolabeled microspheres 2 h after LAD ligation. As compared with CNBF in untreated hearts, endocardial CNBF in hearts receiving S-dobutamine (5 micrograms/kg/min i.v.) increased from 26 +/- 8 to 49 +/- 15 ml/min/100 g in tissue at risk, from 102 +/- 26 to 217 +/- 50 in "border zone," and from 133 +/- 13 to 215 +/- 41 in tissue not at risk. CNBF values in animals receiving vehicle infusion were not significantly different from CNBF values measured after ligation only. The S-enantiomer of dobutamine, infused in dogs for 54 h after coronary artery ligation, maintained cardiac performance, electrolyte balance, and myocardial cellular viability and reduced incidences of arrhythmias through its ability to increase CNBF without increasing HR.

Thyroid peroxidase glycosylation: the location and nature of the N-linked oligosaccharide units in porcine thyroid peroxidase.

Highly purified, trypsin/detergent-solubilized thyroid peroxidase (TPO), prepared from pig thyroid tissue, was subjected to reduction and alkylation followed by trypsin digestion. The resulting peptides were fractionated using HPLC. Corresponding carbohydrate positive regions from three separate HPLC experiments were pooled and further chromatography was carried out to yield purified peptide suitable for sequence analysis and complete carbohydrate composition analysis. Four of the five putative sites for N-linked glycosylation were found to carry oligosaccharide units in which mannose and glucosamine were the sole or predominant sugars. Three of the four glycosylations occur at asparagine residues which are likely to be at beta turns or bends. The fifth putative glycosylation site could not be confirmed and may either be poorly glycosylated or escape glycosylation. All of the confirmed glycosylated sites occur in the N-terminal third of the TPO polypeptide chain, in the portion of the molecule believed to be extracellular. The isolation of at least two chromatographic forms of glycopeptide derived from each of the confirmed sites suggests microheterogeneity in the structure of the oligosaccharide units of thyroid peroxidase similar to that observed in many other glycoproteins.