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R Schulz

Publications and source records attributed to R Schulz.

At least 37 records · Page 2Linked to original sources
PubMed2005

Temporal lobe epilepsy with hippocampal sclerosis: predictors for long-term surgical outcome.

Temporal lobe epilepsy (TLE) accompanied by hippocampal sclerosis (HS) is the type of epilepsy most frequently operated on. The predictors for long-term seizure freedom after surgery of TLE-HS are unknown. In this study, we aimed to identify prognostic factors which predict the outcome 6 months and 2, 3 and 5 years after epilepsy surgery of TLE-HS. Our working hypothesis was that the prognostic value of potential predictors depended on the post-operative time interval for which the assessment was made. We included 171 patients (100 females and 71 males, aged 16-59 years) who had undergone presurgical evaluation, including video-EEG, who had had MRI-defined HS, and who had undergone temporal lobectomy. We found that secondarily generalized seizures (SGTCS) and ictal dystonia were associated with a worse 2-year outcome. Both these variables together with older age and longer epilepsy duration were also related to a worse 3-year outcome. Ictal limb dystonia, older age and longer epilepsy duration were associated with long-term surgical failure evaluated 5 years post-operatively. In order to determine the independent predictors of outcomes, we calculated multivariate analyses. The presence of SGTCS and ictal dystonia independently predicted the 2-year outcome. Longer epilepsy duration and ictal dystonia predicted the 3-year outcome. Longer epilepsy duration (P = 0.003) predicted a poor 5-year outcome. Conclusively, predictors for the long-term surgical results of TLE with HS are different from those variables that predict the short-term outcome. Epilepsy duration is the most important predictor for long-term surgical outcome. Our results strongly suggest that surgery for TLE-HS should be performed as early as possible.

Adolescent↗
PubMed2005

[Therapy of pulmonary arterial hypertension].

New drugs for pulmonary arterial hypertension have shown efficacy in randomized controlled trials. Endothelin receptor antagonists (ERA) and prostanoids are most important for clinical practice. Bosentan represents the first approved orally active therapy for PAH. Besides its hepatotoxicity it is mostly well tolerated. The first approved prostanoid, epoprostenol, is currently first choice only for decompensated right heart failure in PAH. It has to be delivered continuously intravenously and is prone to complications, side effects and very high costs. Alternatively, subcutaneous treprostinil can be applied. It is less risky and expensive but may cause local pain at the infusion site. Inhaled iloprost combines the features of a prostanoid with pulmonary and intrapulmonary selectivity. Alternatively, iloprost is being used as continuous intravenous infusion. The phosphodiesterase-5 inhibitor sildenafil was effective in two randomized controlled trials but has not been approved for PAH therapy.

Antihypertensive Agents↗
PubMed2005

[Pulmonary hypertension and sleep-related breathing disorders].

Pulmonary hypertension (PH), i. e. an increase of mean pulmonary artery pressure above 20 mm Hg under resting conditions, can be observed in different forms of sleep-disordered breathing (SDB). In obstructive sleep apnea (OSA) the apnea-associated triggers of hypoxia and intrathoracic pressure swings lead to repetitive rises of pulmonary artery pressure during sleep. In 20 - 30 % of these patients daytime PH occurs. PH in the setting of OSA is usually mild and rarely causes clinically evident cor pulmonale. Effective CPAP therapy has a beneficial influence on pulmonary hemodynamics in OSA. Severe congestive heart failure (i. e. with a LVEF < 40 %) might provoke pulmonary venous hypertension and thereby stimulation of pulmonary stretch and irritant receptors. The ensuing hyperventilation leads to a decrease of pCO (2) levels below the apneic threshold and thus contributes to the emergence of Cheyne Stokes respiration (CSR) in up to one half of the affected patients. Patients suffering from advanced idiopathic pulmonary arterial hypertension (IPAH) might show a similar breathing pattern while asleep. Possible pathogenetic factors of the nocturnal periodic breathing occurring in end-stage IPAH are prolonged circulation times and hypocapnia. In conclusion, SDB might cause PH (OSA-associated PH). On the other hand, PH might lead to the development of SDB (CSR in congestive heart failure, periodic breathing in IPAH).

Heart Failure↗
PubMed2005

Effect of thallium fractions in the soil and pollution origins on Tl uptake by hyperaccumulator plants: a key factor for the assessment of phytoextraction.

Phytoremediation is often discussed as a means of extracting trace metals in excess in the soil, but to increase its efficiency a better understanding of the factors controlling plant uptake is required. The main objective of this study was to examine the effect of origin (anthropogenic vs. geogenic) and mobility of thallium (Tl) in the rhizosphere on Tl uptake. Two Tl-hyperaccumulating Brassicaceae species, kale (Brassica oleracea acephala L. cv. Winterbor F1) and candytuft (Iberis intermedia Guers.), were grown in a rhizobox system to investigate the dynamics of Tl in the rhizosphere soil. Four different soils were used. Two soils contained high Tl amounts due to anthropogenic sources (emissions from a cement plant and mining activities). High Tl content in the two other soils was due to a high rock content (geogenic origin). On completion of growth in the rhizoboxes, the depletion of Tl in seven different chemical fractions, determined by sequential extraction, was compared to the plant uptake. Most of the Tl taken up was derived from the so-called "easily accessible" fractions in both soils with geogenic Tl as well as in the soils polluted by mining activities. Due to the small amounts of easily accessible Tl in the geogenic soils, Tl uptake by Brassicaceae was low. On the other hand, for the air emission-polluted soil, a high depletion of Tl from "less accessible" fractions was observed in addition to depletion of the easily accessible fractions. Hence, the latter soil demonstrated the highest potential for effective soil decontamination by phytoextraction within an appropriate time frame.

Biodegradation, Environmental↗
PubMed2005

Changes in extracranial arteries in obstructive sleep apnoea.

Obstructive sleep apnoea (OSA) is linked with increased cardiovascular morbidity and mortality, possibly through an enhancement of atherosclerotic vascular changes. Up to now, however, only a few studies have tried to evaluate the occurrence of atherosclerosis in patients with OSA. In the present study, ultrasonography of the large extracranial vessels was performed in a group of consecutively admitted OSA patients (n = 35) and a control group of non-OSA patients (n = 35). Common carotid artery-intima media thickness (CCA-IMT) was measured at the far wall of both proximal carotid arteries. Furthermore, the presence of plaques and stenoses of the extracranial vessels was determined. All measurements were carried out blinded to the status of the patients. In the OSA group, CCA-IMT was significantly increased when compared with the non-OSA patients and was related to the degree of nocturnal hypoxia. Additionally, the formation of plaques was more pronounced and extracranial vessel stenosis was more common in the OSA patients. In conclusion, these findings are in favour of an independent influence of obstructive sleep apnoea on atherosclerotic changes of the arterial wall, and represent further strong arguments for obstructive sleep apnoea being a risk factor on its own for the emergence of cardiovascular disease.

Age Distribution↗
PubMed2005

Spike frequency is dependent on epilepsy duration and seizure frequency in temporal lobe epilepsy.

OBJECTIVES: We wanted to investigate factors that are associated with frequency of interictal epileptiform discharges by investigating 303 patients with temporal lobe epilepsy (TLE). METHODS: We included all patients who consecutively underwent the adult presurgical evaluation program at our center and who had intractable, medial TLE with complex partial seizures due to unilateral medial temporal lobe lesions. The interictal EEG samples were automatically recorded and stored on computer. The location and frequency of interictal epileptiform discharges were assessed by visual analysis of interictal EEG samples of 2-minute duration every hour. RESULTS: There were 303 patients (aged 16-63) who met the inclusion criteria. The median interictal epileptiform discharge frequency was 15 IED/h, the median seizure frequency was 4 seizures/month. According to univariate analyses, we found that age at monitoring, epilepsy duration, and higher seizure frequency were associated with higher interictal epileptiform discharge frequency. In the logistic regression analysis, we found that higher seizure frequency (p < 0.001) and longer epilepsy duration (p = 0.007) were independently associated with higher spike frequency, while the age at monitoring was not. CONCLUSIONS: Seizure frequency and epilepsy duration (years of patient's life with seizure activity) were independently associated with IED frequency, suggesting that IED are modulated by seizures.

Adolescent↗
PubMed2004

Evaluating acute toxicity of methyl parathion application in constructed wetland mesocosms.

Wetland ecosystems have reduced ambient levels of various organic and metallic compounds, although their effectiveness on agricultural pesticides is not well documented. Five stations within each of two 10 x 50 m constructed wetlands (two vegetated, two nonvegetated) were selected to measure the fate and effects of methyl parathion (MeP). Following a simulated storm event (0.64 cm of rainfall), aqueous, sediment, and plant samples were collected and analyzed spatially (5, 10, 20, and 40 m from the inlet) and temporally (after 3-10 days) for MeP concentrations and for the impact of those concentrations on the aquatic fauna. Aqueous toxicity to fish decreased spatially and temporally in the vegetated mesocosm. Pimephales promelas survival was significantly reduced, to 68%, at the 10-m station of the nonvegetated wetlands (3 h postapplication), with pesticide concentrations averaging 9.6 microg MeP/L. Ceriodaphnia in both the vegetated and nonvegetated wetlands was sensitive (i.e., a significant acute response to MeP occurred) to pesticide concentrations through 10 days postapplication. Mean MeP concentrations in water ranged from 0.5 to 15.4 microg/L and from 0.1 to 27.0 microg/L in the vegetated and nonvegetated wetlands, respectively. Hyalella azteca aqueous tests resulted in significant mortality in the 5-m vegetated segment 10 days after exposure to MeP (2.2 microg/L). Solid-phase (10-day) sediment toxicity tests showed no significant reduction in Chironomus tentans survival or growth, except for the sediments sampled 3 h postapplication in the nonvegetated wetland (65% survival). Thereafter, midge survival averaged >87% in sediments sampled from both wetlands. These data suggest that wetlands play a significant role in mitigating the effect of MeP exposure in sensitive aquatic biota.

Agriculture↗
PubMed2004

Runoff-related endosulfan contamination and aquatic macroinvertebrate response in rural basins near Buenos Aires, Argentina.

Information in the open literature about the fate and effects of pesticides in small streams from agricultural areas of Argentina is very rare. The objective of the present work was to study the pesticide contamination and potential biological effects in basins that have undergone intense agricultural activity, mainly related to the cultivation of soybeans. Three streams (Maguire, Helves, and Horqueta) with a low-flow discharge (0.1 and 0.2 m3/s) in March close to the city of Arrecifes were studied during the period of maximum insecticide application, between February and April 2001. Various sampling devices were installed to trap suspended particles, runoff, and floodwater plus sediment throughout the study period. The suspended-particle samples were analyzed for the insecticides endosulfan (END), chlorpyrifos, and cypermethrin. Water chemistry and the macroinvertebrate communities were assessed on four occasions and the organismic drift was measured continuously. Following a 184-mm rainfall on March 1, 2001, beta-endosulfan concentrations up to 318 and 43 microg/kg were measured from suspended-particle samples from Horqueta and Helves, respectively. No END contamination was detected in Maguire. Chlorpyrifos and cypermethrin were not detected in any of the streams. A significant decrease in the average macroinvertebrate species density was observed in Horqueta (from 12.8 +/- 0.5 to 9 +/- 0.7 species; ANOVA, p < 0.05) and Helves (from 10.8 +/- 1.7 to 3.3 +/- 1.3 species; p < 0.001) following the same rainfall event at the beginning of March, while the species density in Maguire remained constant at 7.9 +/- 0.3 species. The runoff primarily reduced species abundances of Odonata and Ephemeroptera significantly (p < 0.01) in Horqueta and Helves but not in Maguire. A greater drift of Smicridae (Trichoptera) and Ephemeroptera occurred in Helves and Horqueta during this runoff event, while no changes in the macroinvertebrate drift were detectable in Maguire. This study highlights the potential pesticide effects on macroinvertebrate communities in Argentinian rural streams. It is suggested that a small wetland area formed by Maguire between the agriculturally used catchment and the sampling site contributes to the absence of contamination and effects at this site.

Agriculture↗
PubMed2004

Linking in situ bioassays and population dynamics of macroinvertebrates to assess agricultural contamination in streams of the Argentine pampa.

The two local crustacean species Hyalella curvispina and Macrobrachium borelli were chosen for assessment of agricultural contamination in two streams (Horqueta and Maguire) in the Argentine pampa. In parallel with in situ bioassays of both species, the population dynamics and the organismic drift of H. curvispina were investigated throughout the main period of insecticide application, from December 2001 to March 2002. In Maguire none of the current-use insecticides (chlorpyrifos, alpha-cypermethrin, and endosulfan) in question were detected throughout the sampling period. During 1-week intervals with no contamination by insecticides the survival rate of H. curvispina varied between 77 +/- 6% (+/- SE, n = 4) and 85 +/- 3%. In Horqueta during a week with a peak insecticide contamination of 64 microg/kg chlorpyrifos in the suspended particles, a mortality of 100% was observed in the in situ bioassays for both species, H. curvispina and M. borelli. At the same time, in Maguire H. curvispina showed reduced survival rates of 23 +/- 5% and 25 +/- 18% at the two sites, while the survival rate of M. borelli was 60 +/- 11% upstream and 93 +/- 5% downstream, below a wetland. During the period with 100% mortality of H. curvispina in Horqueta, the population density of this species decreased correspondingly, from 106 +/- 26 to 0 individuals/m(2). We conclude that in situ bioassays can be successfully linked to in-stream population dynamics for the same species and that this link is very useful for interpreting causal exposure-effect relationships.

Agriculture↗
PubMed2004

Orgasmic aura--a report of seven cases.

We report on seven patients who experienced an orgasmic aura at the start of their seizures. The patients (five women, two men) were aged 36-58. Three of seven patients described the exact nature of their auras only many years after their appearance, when the epilepsy diagnostic procedure became more intensive due to drug resistance. Moreover, one patient even refused any new therapeutical options due to the reportedly positive role of the orgasmic aura in her life. All of our patients had temporal lobe epilepsy. The clinical picture, EEG, MRI or SPECT findings suggested a right temporal epileptic focus in six patients, while in one patient the epileptogenic region was localised in the left temporal lobe. In the latter case, the left hemisphere was speech-dominant, while in the other cases no Wada tests were done. Our results confirm that orgasmic aura could be considered as an ictal lateralising sign to the right hemisphere, however, it has no 100% lateralising value.

Adult↗
PubMed2004

Role of connexin 43 in ischemic preconditioning does not involve intercellular communication through gap junctions.

Connexin 43 (Cx 43) has recently been implicated in protection of ischemic preconditioning. Cx 43 colocalization with protein kinase C and p38 mitogen-activated protein kinase is increased in preconditioned myocardium, Cx 43 phosphorylation is preserved in preconditioned myocardium, and hearts from Cx 43-deficient mice cannot be preconditioned. It is, however, unclear whether the important role of Cx 43 relates to intercellular communication through gap junctions or its function in volume homeostasis. To address this issue, we used isolated cardiomyocytes, which no longer-form gap junctions, from wild-type (n = 5) and heterozygous Cx 43-deficient mice (n = 8) and subjected them to 2 h simulated ischemia (hypoxia, acidosis) and an additional challenge by extracellular hypo-osmolarity (from 310 to 250 mOsm/l). Viability (trypan blue exclusion) was well maintained in normoxic wild-type cardiomyocytes (54 +/- 5% at baseline vs. 46 +/- 4 (mean +/- S.D.) % at 2 h). With simulated ischemia, viability was reduced to 17 +/- 5%. Preconditioning by a preceding exposure to 10 min simulated ischemia and 15 min reoxygenation preserved viability after 2 h simulated ischemia (36 +/- 1%, P < 0.001 vs. simulated ischemia). In Cx 43-deficient cardiomyocytes, viability was also well maintained in normoxia (56 +/- 10% vs. 44 +/- 10%). Viability was also reduced to 17 +/- 6% with 2 h simulated ischemia. In contrast to wild-type cells, preconditioning did not prevent the reduction in viability (18 +/- 8%). In conclusion, Cx 43 is essential for preconditioning in the absence of gap junctions, supporting its function through improved volume regulation.

Animals↗
PubMed2004

Intentional seizure interruption may decrease the seizure frequency in drug-resistant temporal lobe epilepsy.

We investigated the nature of preictal subjective phenomena and whether they had any effect on the seizure frequency in 95 adult patients with medial temporal lobe epilepsy. Seventy-three (77%) patients indicated that they experienced seizure-provoking factors. Ten patients (11%) had prodromas independent of auras, while auras occurred in 89%. Forty-four patients (46%) reported that that they had tried to stop their seizures in the presence of prodroma or aura and this action had resulted in success at least once. Twenty-one patients (22%) regularly tried to stop their seizures because this effort was often successful according to their interpretation. Patients who reported that they could frequently inhibit their seizures had 1.8 +/- 1.6 seizures/month, a significantly lower mean seizure frequency than those 74 patients who did not do it regularly (4.6 +/- 4.8 seizures/month, P<0.001). Patients who reported regular experience in inhibiting intentionally their seizures more often had affective (P=0.05) and vertiginous auras (P<0.01) as well as isolated auras (P<0.05). Patients who experienced provoking factors showed the same seizure frequency as those who did not. Our results suggest that intentional seizure inhibition had an impact on the severity of drug-resistant epilepsy.

Adolescent↗
PubMed2004

Simple partial seizures (isolated auras) in medial temporal lobe epilepsy.

We analysed whether the medial temporal lobe epilepsy (MTLE) with isolated auras makes any difference in the clinical picture in comparison with MTLE in which only complex partial seizures (CPS) occur. We included 100 patients (aged 16-59 years) with unilateral medial temporal lobe lesions who consecutively underwent presurgical evaluation due to intractable MTLE and who became completely aura- and seizure-free after the anterior temporal resection. Preoperatively, isolated auras were present in 70 patients. These patients were categorised into the IA group. The remaining 30 patients in whom the auras preceded seizures were categorised into the NIA group. We found no difference between the two groups for the age at onset, epilepsy duration or aura types. Conversely, a right-sided epileptogenic region (61%) occurred more frequently in the IA group than in the NIA group (27%, P = 0.001). Conclusively, isolated auras show affinity to the right hemisphere. One explanation may be that seizures stop more quickly in the right hemisphere. Another hypothesis is that consciousness can be disturbed much easier by the ictal activity in left temporal seizures: auras evolve more frequently to CPS due to the disturbance of consciousness.

Adolescent↗
PubMed2004

Bilateral mesial temporal lobe epilepsy: comparison of scalp EEG and hippocampal MRI-T2 relaxometry.

OBJECTIVE: Bilateral hippocampal abnormality is frequent in mesial temporal lobe sclerosis and might affect outcome in epilepsy surgery. The objective of this study was to compare the lateralization of interictal and ictal scalp EEG with MRI T2 relaxometry. MATERIAL AND METHODS: Forty-nine consecutive patients with intractable mesial temporal lobe epilepsy (MTLE) were studied with scalp EEG/video monitoring and MRI T2 relaxometry. RESULTS: Bilateral prolongation of hippocampal T2 time was significantly associated with following bitemporal scalp EEG changes: (i) in ictal EEG left and right temporal EEG seizure onsets in different seizures, or, after regionalized EEG onset, evolution of an independent ictal EEG over the contralateral temporal lobe (left and right temporal asynchronous frequencies or lateralization switch; P = 0.002); (ii) in interictal EEG both left and right temporal interictal slowing (P = 0.007). Bitemporal T2 changes were not, however, associated with bitemporal interictal epileptiform discharges (IED). Lateralization of bilateral asymmetric or unilateral abnormal T2 findings were associated with initial regionalization of the ictal EEG in all but one patient (P < 0.005), with lateralization of IED in all patients (P < 0.005), and with scalp EEG slowing in 28 (82,4%) of 34 patients (P = 0.007). CONCLUSION: Our data suggest that EEG seizure propagation is more closely related to hippocampal T2 abnormalities than IED. Interictal and ictal scalp EEG, including the recognition of ictal propagation patterns, and MRI T2 relaxometry can help to identify patients with bitemporal damage in MTLE. Further studies are needed to estimate the impact of bilateral EEG and MRI abnormal findings on the surgical outcome.

Action Potentials↗
PubMed2004

Medial temporal lobe epilepsy: gender differences.

The present study investigated the gender differences in medial temporal lobe epilepsy (MTLE) with regard to clinical history, seizure semiology, and EEG data. To avoid the influence of pathological and localisation differences, we included only MTLE patients with hippocampal sclerosis. Patients who had long term video EEG recordings with registered seizures and unilateral hippocampal sclerosis proved by high resolution MRI were included. There were 153 patients (86 women and 67 men) who met our inclusion criteria. The mean age of the patients was 33.5 years (range 16-59). The mean age at epilepsy onset was 10.8 years. Although there were more women than men, this difference was not significant (p = 0.15). We found that male patients experienced generalised seizures significantly more often, and isolated auras significantly less often than female patients. Analysing EEG data, we found that a seizure pattern lateralised to the side of the hippocampal sclerosis occurred more often in female patients. In the logistic regression analysis, we found that all three factors were associated independently with gender. Odds ratio (OR) for female gender in patients with generalised seizures was 0.44 (95% confidence interval (95% CI) 0.21 to 0.92; p<0.05). In patients with isolated auras OR for female gender was 2.1 (95% CI 1.1 to 4.2; p<0.05). OR for female gender in patients with lateralised seizure pattern was 8.8 (95% CI 1.8 to 42.7; p<0.01). Men more often had secondarily generalised tonic-clonic seizures, while women had isolated auras and lateralised EEG seizure pattern more often. Our data suggest that the seizure spread is more extended or occurs more frequently in men than in women.

Adolescent↗