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1.
Childs Nerv Syst ; 34(7): 1423-1425, 2018 07.
Article in English | MEDLINE | ID: mdl-29508057

ABSTRACT

INTRODUCTION: The ciliopathy "Joubert syndrome" was first described in 1969 by Dr. Marie Joubert and most subtypes follow an autosomal recessive inheritance. The complex disorder shows typical clinical features, such as hyperventilation, abnormal eye movements, and retardation. A pathognomonic midbrain-hindbrain malformation, the molar tooth sign, can be found on magnetic resonance imaging of the brainstem. There are a little more than 200 reports of Joubert syndrome in the literature. CASE PRESENTATION: We report a case of a 9-year-old boy who developed a progressive hydrocephalus starting from the age of 4. He underwent VP shunt placement at 8 years, which relieved hydrocephalus-related clinical symptoms and put development of the macrocephalus to a halt. CONCLUSION: Neonatal hydrocephalus due to the altered anatomy of the posterior fossa has been reported earlier, but to our knowledge, this is the first case of a delayed onset of hydrocephalus in a patient with Joubert syndrome.


Subject(s)
Cerebellum/abnormalities , Eye Abnormalities/complications , Hydrocephalus/etiology , Kidney Diseases, Cystic/complications , Retina/abnormalities , Abnormalities, Multiple/diagnostic imaging , Abnormalities, Multiple/genetics , Cerebellum/diagnostic imaging , Child , Eye Abnormalities/diagnostic imaging , Eye Abnormalities/genetics , Follow-Up Studies , Humans , Hydrocephalus/diagnostic imaging , Kidney Diseases, Cystic/diagnostic imaging , Kidney Diseases, Cystic/genetics , Magnetic Resonance Imaging , Male , Mutation/genetics , Proteins/genetics , Retina/diagnostic imaging
2.
Eur J Paediatr Neurol ; 22(3): 427-433, 2018 May.
Article in English | MEDLINE | ID: mdl-29475820

ABSTRACT

BACKGROUND: The main source of knowledge on adverse drug events (ADE) are physicians' reports in controlled clinical trials. In contrast, little is known about the parents' perception of ADE of anticonvulsants their children receive. METHODS: After approval by the local ethics committee, we performed a survey in a neuropediatric outpatient clinic of a university hospital. Based on a structured questionnaire, we interviewed parents of children with current anticonvulsant treatment regarding (i) their fears about potential ADE, (ii) experienced ADE according to parents, and (iii) implications of ADE on the child's life. RESULTS: Parents of 150 patients took part in the interview. (i) 95 (63.3%) parents expressed fears concerning ADE, mostly liver injury/liver failure (33 [22%]). (ii) 129 (86%) parents reported experienced ADE, mostly sedation (65 [43.3%]) and abnormal behavior (54 [36%]). (iii) Parents reported substantial implications of ADE on the child's daily life for 84 (56%) children, and 63 (42%) parents expressed a negative impact on the child's development. CONCLUSION: We recognized a great discrepancy between those ADE that were feared and those that were experienced. Parents feared life-threatening ADE and experienced less severe ADE that nevertheless have a negative impact on the child's daily life.


Subject(s)
Anticonvulsants/adverse effects , Drug-Related Side Effects and Adverse Reactions/psychology , Parents/psychology , Child , Child, Preschool , Female , Humans , Infant , Male , Surveys and Questionnaires
3.
Leg Med (Tokyo) ; 28: 27-30, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28755627

ABSTRACT

In order to accurately diagnose child abuse or neglect, a physician needs to be familiar with diseases and medical conditions that can simulate maltreatment. Unrecognized cases of abuse may lead to insufficient child protection, whereas, on the other hand, over-diagnosis could be the cause of various problems for the family and their potentially accused members. Regarding child abuse, numerous cases of false diagnoses with undetected causes of bleeding are described in the scientific literature, but, specifically concerning leukemia in childhood, only very few case reports exist. Here, for the first time, we report a case of a 2-year-old boy who got hospitalized twice because of suspicious injuries and psychosocial conspicuities, in a family situation known for repeated endangerment of the child's well-being. After his first hospitalization with injuries typical for child abuse, but without paraclinical abnormalities, medical inspections were arranged periodically. The child was hospitalized with signs of repeated child abuse again five months later. During second admission, an acute lymphoblastic leukemia was revealed by intermittent laboratory examination, ordered due to new bruises with changes in morphology, identifiable as petechial hemorrhages. This case elucidates the discussion of known cases of leukemia in childhood associated with suspected child abuse in order to provide an overview of possible diseases mimicking maltreatment. To arrange necessary supportive examinations, a skillful interaction between pediatrician and forensic pathologist is crucial in the differentiation between accidental and non-accidental injury.


Subject(s)
Child Abuse/diagnosis , Child Abuse/legislation & jurisprudence , Clinical Laboratory Techniques , Diagnostic Errors , Child, Preschool , Hemorrhage/physiopathology , Humans , Male , Precursor Cell Lymphoblastic Leukemia-Lymphoma
6.
Methods Enzymol ; 555: 3-18, 2015.
Article in English | MEDLINE | ID: mdl-25747472

ABSTRACT

4-HNE (4-hydroxy-2-nonenal) is a highly reactive α,ß-unsaturated aldehyde generated from oxidation of polyunsaturated fatty acids and has been suggested to play a role in the pathogenesis of several diseases. 4-HNE can bind to amino acids, proteins, polynucleotides, and lipids and exert cytotoxicity. 4-HNE forms adducts (Michael adducts) with cysteine, lysine, as well as histidine on proteins with the thiol function as the most reactive nucleophilic moiety. Thus, detoxification strategies by 4-HNE scavenging compounds might be of interest. Recently, hydrogen sulfide (H2S) has been identified as an endogenous vascular gasotransmitter and neuromodulator. Assuming that the low-molecular thiol H2S may react with 4-HNE, methods to monitor the ability of H2S to counteract the protein-modifying and cytotoxic activity of 4-HNE are described in this chapter.


Subject(s)
Aldehydes/toxicity , Fatty Acids, Unsaturated/toxicity , Hydrogen Sulfide/pharmacology , Hydroxy Acids/toxicity , Serum Albumin/chemistry , Sulfhydryl Compounds/chemistry , Aldehydes/chemistry , Aldehydes/metabolism , Cell Line, Tumor , Cell Survival/drug effects , Electrophoresis, Polyacrylamide Gel , Fatty Acids, Unsaturated/chemistry , Fatty Acids, Unsaturated/metabolism , Humans , Hydrogen Sulfide/chemistry , Hydrogen-Ion Concentration , Hydroxy Acids/chemistry , Hydroxy Acids/metabolism , Immunoblotting , Neurons/chemistry , Neurons/drug effects , Neurons/pathology , Oxidation-Reduction , Sulfides/chemistry
7.
Biochimie ; 112: 187-95, 2015 May.
Article in English | MEDLINE | ID: mdl-25795259

ABSTRACT

The transcription factor HIF-1α regulates the adaptive response of cells to hypoxia and oxidative stress. In addition, an important regulatory role for HIF-1α in immune reactions and inflammation is suggested. The present study attempts to investigate the effect of the gaseous signalling molecule hydrogen sulphide (H2S) on HIF-1α in THP-1 macrophages using the slow H2S releasing donor GYY4137. We found that H2S induced HIF-1α protein accumulation in THP-1 macrophages in a concentration-dependent manner. Western blot analysis of cell fractions showed that HIF-1α protein translocates into the nucleus and leads to an increase of its target protein glucose transporter-1 (GLUT-1). Activation of nuclear factor-κB (NF-κB), as well as secretion of the pro-inflammatory cytokines tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6), were reduced in the presence of H2S. These findings indicate that HIF-1α accumulation due to H2S was not triggered by the NF-κB pathway. The antioxidant pathway Nrf2/HO-1 (nuclear factor erythroid 2-related factor 2/heme oxygenase-1) was activated by H2S. Inhibition of the p38 mitogen-activated protein kinase (MAPK) reversed H2S mediated effects, suggesting that the p38 MAPK pathway may be involved in H2S induced HIF-1α/Nrf2 signalling pathways.


Subject(s)
Hydrogen Sulfide/pharmacology , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , MAP Kinase Signaling System/drug effects , Macrophages/metabolism , NF-E2-Related Factor 2/metabolism , Cell Line, Tumor , Dose-Response Relationship, Drug , Heme Oxygenase-1/metabolism , Humans , Interleukin-6/metabolism , Macrophages/cytology , NF-kappa B/metabolism , Tumor Necrosis Factor-alpha/metabolism
8.
Klin Padiatr ; 227(2): 84-8, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25419720

ABSTRACT

BACKGROUND: After a first afebrile seizure, EEG in addition to cMRI is recommended for pediatric patients. Once indications requiring immediate treatment are excluded, it is of interest to determine if the results provide a prognostic tool for seizure relapses. METHODS: Patients aged between 1 month and 18 years who had a first afebrile seizure between 2006 and 2008 were retrospectively studied and monitored for another 48 months. RESULTS: Out of 248 patients, 62.5% had generalized and 36.3% focal seizures. 34.7% of the EEG results were pathological. 176 patients had a cMRI that showed in 23.3% probable epileptogenic lesions. 3 patients with benign cerebral tumours needed surgical therapy. In the following 48 months 29.4% of the children showed seizure relapses. There was a correlation between epileptic patterns in the EEG and further seizures (p=0.0001). However, the sensitivity of the EEG based diagnoses was 0.6, the specificity 0.78 and the positive predictive value 0.52. There was no correlation between epileptogenic lesions and the probability of seizure relapses. The sensitivity of the cMRI to this effect was 0.36, the specificity 0.74 and the positive predictive value 0.34. DISCUSSION: The EEG is superior to cMRI for predicting seizure relapses. The percentage of noticeable cMRI findings is high but this has low therapeutic relevance and is assumed to largely represent "incidental findings". It is important to question the value of MRI investigations for sedated small children except in the case of emergencies. The key question is whether the cMRI should be deployed to diagnose epilepsy, the probability of seizure recurrences or to classify the entity of a most likely epilepsy.


Subject(s)
Brain Diseases/diagnosis , Brain Diseases/physiopathology , Brain Neoplasms/diagnosis , Brain Neoplasms/physiopathology , Brain/pathology , Brain/physiopathology , Electroencephalography , Epilepsy/diagnosis , Epilepsy/physiopathology , Magnetic Resonance Imaging , Seizures/etiology , Adolescent , Child , Child, Preschool , Female , Humans , Incidental Findings , Infant , Male , Predictive Value of Tests , Recurrence , Retrospective Studies , Risk Assessment
9.
Childs Nerv Syst ; 31(1): 49-56, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25323796

ABSTRACT

INTRODUCTION: Even though shunt surgery has been an established and widely accepted treatment for congenital hydrocephalus for five decades, long-term follow-up and functional outcome data is rare. PATIENTS AND METHODS: Sixty-nine patients were examined after congenital hydrocephalus had been treated between 1971 and 1987 at the Department of Pediatric Surgery (University of Leipzig) within the first 12 months of life. Median age of patients was 32 years (range 25-42 years). Patients agreed to undergo a contemporary hydrocephalus assessment. RESULTS: Seven patients (10.1%) became shunt-independent before adulthood. By the age of 20, 82% of the patients had needed at least one shunt revision, 100% by the age of 30. 21.7% of the primary valves (Spitz-Holter) remained intact without revision until today up to 35 years (mean functional intactness 23 years). Shunt infections occurred in 4.3% of primary implantations. 48% of the patients had a good functional outcome (mRS = 0-1). 40.9% of the patients attended regular school. In summary, 75% patients work on a daily basis. 44.6% live an independent life, 35.4% rely on parental supervision, and 20% depend on professional care institutions. CONCLUSION: Compared to the pre-shunt era, surgery within the first year of life is advantageous regarding visual function, educational progress, and social results. The outcome achieved throughout childhood remains stable during adult life as long as catastrophic events of shunt malfunction can be prevented. Epilepsy, motor deficits, acute shunt dysfunction, and problems of social integration as well as aging parental caregivers seem to be prominent factors of morbidity in adulthood.


Subject(s)
Hydrocephalus/surgery , Treatment Outcome , Ventriculoperitoneal Shunt/methods , Adolescent , Adult , Equipment Failure , Female , Humans , Kaplan-Meier Estimate , Longitudinal Studies , Male , Retrospective Studies , Severity of Illness Index , Ventricular Dysfunction/etiology , Ventriculoperitoneal Shunt/adverse effects , Young Adult
10.
Fortschr Neurol Psychiatr ; 82(1): 39-42, 2014 Jan.
Article in German | MEDLINE | ID: mdl-24446117

ABSTRACT

BACKGROUND: The prevalence of chronic headaches in children and adolescents is up to 2 % resulting in the beginning of the later typical headache careers of adults. The therapy for chronic migraine with botulinum toxin is now established in adults. However, there is only limited experience in the use of botulinum toxin in paediatric patients. METHODS: 10 patients aged 13 - 17 years who suffered from chronic migraine according to the IHS criteria were injected at 31 specific injection points of the head and neck muscles with a total amount of 150 IE of botulinum toxin A (Botox®) according to the approved scheme. The number of headache days per month over the following 9 months was recorded and side effects were retrospectively determined. RESULTS: The responder rate (that is reduction of headache days per month more than 50 %) was 7/10 at three months after the injection. On average the number of headache days per month was reduced from 19.2 days to a minimum of 10.1 days. After three to six months the number of headache days increased again in all responders. Slight local side effects such as redness or temporary pain were observed in all patients, but severe side effects such as infections, fever, ptosis or allergic reactions did not occur. DISCUSSION: This small case series shows that the therapy for chronic migraine with botulinum toxin A can also be effective and safe in adolescents. As many adolescents still suffer from headaches later as adults a link between neuropaediatricians and neurologists is justifiable. An early botulinum toxin therapy followed by the transition of the adolescents would be helpful.


Subject(s)
Botulinum Toxins, Type A/therapeutic use , Migraine Disorders/drug therapy , Neuromuscular Agents/therapeutic use , Adolescent , Adrenergic beta-Antagonists/therapeutic use , Botulinum Toxins, Type A/administration & dosage , Botulinum Toxins, Type A/adverse effects , Chronic Disease , Female , Fructose/analogs & derivatives , Fructose/therapeutic use , Humans , Male , Metoprolol/therapeutic use , Neurology , Neuromuscular Agents/administration & dosage , Neuromuscular Agents/adverse effects , Neuroprotective Agents/therapeutic use , Pediatrics , Retrospective Studies , Topiramate , Transcutaneous Electric Nerve Stimulation , Treatment Outcome
11.
Free Radic Biol Med ; 75 Suppl 1: S36, 2014 Oct.
Article in English | MEDLINE | ID: mdl-26461354

ABSTRACT

Uremic toxins have been shown to play a role in chronic kidney disease (CKD) associated oxidative stress. Oxidative stress and inflammation have been associated with increased risk of cardiovascular disease in uraemia. The oxidative modification of LDL may play a role in early atherogenesis. Enhanced LDL oxidation has been found in uremic patients which may account for accelerated atherosclerosis observed in CKD. The uremic toxin indoxyl sulfate (IS) has been reported to exert oxidative and antioxidative activity. Thus, in the present study we have investigated the influence of IS on the atherogenic modifications of LDL exposed in vitro to different oxidising systems. The transition metal ion (Cu(2) ) and hemin/H2O2 induced lipid oxidation reactions monitored by conjugated diene formation, were inhibited by the presence of IS, which points to possible antioxidant effects by this uremic toxin. A protective effect of IS on LDL apoprotein modification by the exposure to the product of the myeloperoxidase/H2O2/Cl(-) system HOCl, was also observed as estimated by protein carbonyl formation. In contrast, a marked increase in conjugated dienes and lipid hydroperoxides was observed when lipid oxidation was initiated by the free radical generator AAPH in presence of IS. The GC-MS analysis revealed the formation of indole-2,3-dione and 6,12-dihydro-6,12-dioxo-indolo[2,1-b]quinazoline (tryptanthrine) in IS/AAPH reaction. A scheme for the generation of tryptanthrine from IS via indoxyl radicals is proposed, which may facilitate LDL lipid oxidation. Our observations add further insight in the Janus-faced properties of this important uremic toxin.

12.
Dtsch Med Wochenschr ; 138(42): 2143-5, 2013 Oct.
Article in German | MEDLINE | ID: mdl-24104589

ABSTRACT

HISTORY: A 13-month-old girl suffered from 3 generalized tonic-clonic seizures for several minutes within a total period of 9 hours. History revealed that the child received a total of 5 dimenhydrinate containing suppositories à 40 mg during the previous 2 days (i. e. 23 mg dimenhydrinate per kg body weight) due to enteritis with vomiting. The first seizure occurred 10 hours after the last administration. INVESTIGATIONS: The plasma level of diphenhydramin was 230 µg/l approximately one hour after the first seizure. Electroencephalography showed no pathological signs, an MRI scan of the brain was normal except of several small gliotic spots and body temperature was regularly. TREATMENT AND COURSE: Two stationary occurring seizures were stopped with 5 mg diazepam rectally. Continued surveillance and an EEG two days later showed age-appropriate normal findings. There were no further seizures in the next 4 years. CONCLUSION: Infants have the risk to develop dimenhydrinate intoxication, especially in cases where suppositories were given repeatedly because of intermittent defecation.


Subject(s)
Antiemetics/toxicity , Dimenhydrinate/toxicity , Drug Overdose/diagnosis , Epilepsy, Tonic-Clonic/chemically induced , Gastroenteritis/drug therapy , Antiemetics/administration & dosage , Dimenhydrinate/administration & dosage , Dose-Response Relationship, Drug , Drug Administration Schedule , Electroencephalography/drug effects , Female , Follow-Up Studies , Humans , Infant , Suppositories
13.
Klin Padiatr ; 225(5): 277-82, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23946090

ABSTRACT

BACKGROUND: Anticonvulsants require special consideration particularly at the interface from hospital to ambulatory care. PATIENTS AND METHOD: Observational study for 6 months with prospectively enrolled consecutive patients in a neuropediatric ward of a university hospital (age 0-<18 years) with long-term therapy of at least one anticonvulsant. Assessment of outpatient prescriptions after discharge. Parent interviews for emergency treatment for acute seizures and safety precautions. RESULTS: We identified changes of the brand in 19/82 (23%) patients caused by hospital's discharge letters (4/82; 5%) or in ambulatory care (15/82; 18%). In 37/76 (49%) of patients who were deemed to require rescue medication, no recommendation for such a medication was included in the discharge letters. 17/76 (22%) of the respective parents stated that they had no immediate access to rescue medication. Safety precautions were applicable in 44 epilepsy patients. We identified knowledge deficits in 27/44 (61%) of parents. CONCLUSION: Switching of brands after discharge was frequent. In the discharge letters, rescue medications were insufficiently recommended. Additionally, parents frequently displayed knowledge deficits in risk management.


Subject(s)
Ambulatory Care , Anticonvulsants/adverse effects , Anticonvulsants/therapeutic use , Epilepsy/drug therapy , Patient Discharge , Adolescent , Child , Child, Preschool , Drug Substitution , Drug Therapy, Combination , Female , Health Knowledge, Attitudes, Practice , Humans , Infant , Long-Term Care , Male , Medication Adherence , Parents/education , Prospective Studies , Risk Management
14.
Biochimie ; 95(11): 2069-75, 2013 Nov.
Article in English | MEDLINE | ID: mdl-23896375

ABSTRACT

Hydrogen sulfide (H2S) has been identified as the third gasotransmitter. Beside its role as signaling molecule in the cardiovascular and nervous system the antioxidant and cyto-protective properties of H2S have gained much attention. In the present study we show that cyanate, an uremic toxin which is found in abundant concentration in sera of patients suffering from chronic kidney disease (CKD), can abrogate the antioxidant and cytoprotective activity of H2S via S-carbamoylation reaction, a reaction that previously has only been shown to have a physiological effect on cysteine groups, but not on H2S. Carbamoylation strongly inhibited the free radical scavenging (ABTS(+·) and alkylperoxyl ROO(·)) properties of H2S. The extent of intracellular ROS formation induced by ROO(·) was diminished by H2S whereas carbamoylation counteracted the protective effect. Reagent HOCl was rapidly inactivated by H2S in contrast to the carbamoylated compound. Protein modification by HOCl was inhibited by H2S but carbamoylation significantly reduced the effect. Thus, S-carbamoylation of low molecular weight thiols by abrogating their antioxidant potential may contribute to the higher oxidative stress observed in CKD.


Subject(s)
Cyanates/metabolism , Hydrogen Sulfide/metabolism , Oxidative Stress , Renal Insufficiency, Chronic/metabolism , Antioxidants/metabolism , Cell Line , Cyanates/chemistry , Cysteine/analogs & derivatives , Cysteine/chemistry , Cysteine/metabolism , Free Radical Scavengers/blood , Free Radical Scavengers/chemistry , Free Radical Scavengers/metabolism , Humans , Hydrogen Sulfide/chemistry , Renal Insufficiency, Chronic/pathology , Signal Transduction
15.
Pediatr Neurosurg ; 49(2): 81-5, 2013.
Article in English | MEDLINE | ID: mdl-24435068

ABSTRACT

INTRODUCTION: Bevacizumab has been reported to effectively reduce cerebral edema caused by radiation therapy. However, only limited data with a short follow-up in tumor patients are available so far. PATIENTS AND METHODS: Two children suffering from hemorrhage from arteriovenous malformation (AVM) have been treated with stereotactic radiotherapy and developed radiation-induced cerebral edema with deteriorating neurological status despite maximized steroid therapy. Bevacizumab administration at 5 mg/kg body weight was initiated every 2 weeks. RESULTS: Bevacizumab treatment rapidly ameliorated the neurological deficits, malignant edema and prevented catastrophic complications. Corticoid therapy could be reduced and discontinued. However, after 18 months, both patients showed identical or worse neurological status than before bevacizumab therapy. AVM radiation therapy had been successful to completely obliterate AVMs. DISCUSSION: In our limited experience, bevacizumab may be an effective and safe option for rescue therapy for malignant cerebral edema on the basis of radiation-induced necrosis especially in patients who experience rapid deterioration despite corticoid therapy and/or intolerable steroid side effects. Despite the fact that functional improvement could not be achieved in long-term outcome patients significantly stabilized and improved during periods of acute deterioration. In order to determine the long-term effectiveness of bevacizumab further investigation in placebo-controlled studies with a higher number of patients are required.


Subject(s)
Antibodies, Monoclonal, Humanized/therapeutic use , Brain Edema/drug therapy , Brain Edema/etiology , Intracranial Arteriovenous Malformations/radiotherapy , Radiation Injuries/drug therapy , Bevacizumab , Brain Edema/diagnosis , Child , Female , Humans , Intracranial Arteriovenous Malformations/diagnosis , Male , Necrosis/diagnosis , Necrosis/drug therapy , Necrosis/etiology , Radiation Injuries/diagnosis , Treatment Outcome
16.
Biochimie ; 94(11): 2441-7, 2012 Nov.
Article in English | MEDLINE | ID: mdl-22776434

ABSTRACT

N-carbamoylation is the non-enzymatic reaction of cyanate with amino groups. Due to urea-formed cyanate in uremic patients beside carbamoylated proteins also free amino acid carbamoylation has been detected, a modification which has been linked to disturbed protein synthesis as NH(2)-derivatisation interferes with peptide bond formation. HOCl the product of the activated MPO/H(2)O(2)/Cl(-) system is known to react with the NH(2)-group of free amino acids to form chloramines which could exert some protective effect against protein modification and cytotoxicity induced by HOCl. As N-carbamoylation may inhibit formation of chloramines we have used N-carbamoyl-threonine as a model amino acid to study its ability to limit the reactivity of HOCl with proteins (LDL and human serum albumin) and cells (THP-1 monocytes and coronary artery endothelial cells). The data indicate that N-carbamoylation completely abolished the protein- and cell-protective effect of threonine against HOCl attack. In contrast to threonine the reaction of HOCl with carbamoyl-threonine resulted in the formation of volatile oxidant species with protein modifying and cytotoxic potential. The volatile lipophilic inorganic monochloramine (NH(2)Cl) was identified as a breakdown product of this reaction.


Subject(s)
Carbamates/metabolism , Cytotoxins/toxicity , Hypochlorous Acid/toxicity , Lipoproteins, LDL/metabolism , Oxidants/toxicity , Serum Albumin/metabolism , Threonine/analogs & derivatives , Threonine/metabolism , Uremia/metabolism , Aldehydes/metabolism , Cell Line , Humans , Volatilization
17.
Biochimie ; 93(4): 772-7, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21277933

ABSTRACT

Carbamoylation is the non-enzymatic reaction of cyanate with amino-, hydroxy- or thiol groups. In vivo, amino group modification (N-carbamoylation) resulting in altered function of proteins/amino acids has been observed in patients suffering from uraemia due to urea-derived cyanate. Uraemia has been linked to impaired antioxidant defense. As thiol-compounds like cysteine, N-acetyl cysteine and GSH have oxidant scavenging properties one may speculate that thiol-group carbamoylation (S-carbamoylation) may impair their protective activity. Here we report on the effect of S-carbamoylation on the ABTS free radical and HOCl scavenging property of cysteine as well on its ability to protect LDL from atherogenic modification induced by AAPH generated peroxylradicals or HOCl. The results show that S-carbamoylation impaired the ABTS free radical and HOCl scavenging property of the thiol-compounds tested. The ability of the thiols to protect LDL from lipid oxidation and apolipoprotein modification was strongly diminished by S-carbamoylation. The data indicate that S-carbamoylation could impair the free radical and HOCl scavenging of thiol-amino acids reducing their protective property against LDL atherogenic modification by these oxidant species. As S-carbamoylation is most effective at pH 7 to 5 in vivo thiol-carbamoylation may especially occur at sites of acidic extracellular pH as in hypoxic/inflammatory macrophage rich areas like the atherosclerotic plaque where increased LDL oxidation has been found and may contribute to the higher oxidative stress in uraemia.


Subject(s)
Cholesterol, LDL/metabolism , Cysteine/analogs & derivatives , Cysteine/metabolism , Free Radicals/metabolism , Uremia/metabolism , Antioxidants/metabolism , Benzothiazoles/metabolism , Cholesterol, LDL/chemistry , Cyanates/pharmacology , Cysteine/chemistry , Glutathione/metabolism , Humans , Lipid Peroxidation , Lipoproteins, LDL/metabolism , Oxidative Stress/physiology , Sulfhydryl Compounds/metabolism , Sulfonic Acids/metabolism
18.
Neurotox Res ; 17(3): 249-56, 2010 Apr.
Article in English | MEDLINE | ID: mdl-19680736

ABSTRACT

Highly reactive alpha,beta-unsaturated aldehydes like 4-hydroxy-2-nonenal (4-HNE), generated from oxidation of polyunsaturated fatty acids, can bind to proteins, polynucleotides and exert cytotoxicity. 4-HNE is known to react readily with thiol and amino groups on free or bound amino acids. Recently, hydrogen sulfide (H(2)S) has been identified as an endogenous vascular gasotransmitter and neuromodulator which can reach up to 160 micromol/l in the brain. Markedly higher 4-HNE concentrations were reported in the brain of patients suffering from Alzheimer's disease. Assuming that the low molecular thiol H(2)S may react with 4-HNE, we have tested the ability of H(2)S to counteract the cytotoxic and protein-modifying activity of 4-HNE. The results show that H(2)S at physiologically relevant concentrations could effectively protect neuronal cells (SH-SY5Y) from the cytotoxic action of 4-HNE. The HNE-modification of cellular proteins was also inhibited in presence of H(2)S. These data suggest that H(2)S may be an important protective factor against carbonyl stress by inactivating/modulating the action of highly reactive alpha,beta-unsaturated aldehydes like 4-HNE in the brain.


Subject(s)
Air Pollutants/pharmacology , Aldehydes/metabolism , Aldehydes/pharmacology , Hydrogen Sulfide/pharmacology , Lipid Peroxidation/drug effects , Analysis of Variance , Cell Line, Tumor , Cell Survival/drug effects , Dose-Response Relationship, Drug , Drug Interactions , Electrophoretic Mobility Shift Assay/methods , Humans , Neuroblastoma/pathology
19.
Biochem J ; 420(2): 277-81, 2009 May 13.
Article in English | MEDLINE | ID: mdl-19265508

ABSTRACT

LOOHs (lipid hydroperoxides) in oxLDL [oxidized LDL (low-density lipoprotein)] are potentially atherogenic compounds. Recently, H2S was identified as the third endogenous gasotransmitter in the vasculature. H2O2 is known to be destroyed by H2S. Assuming that H2S may also react with LOOHs, the results show that H2S can destroy LOOHs in oxLDL. The ability of LOOH-enriched LDL to induce HO-1 (haem oxygenase 1) in endothelial cells was abolished by H2S pretreatment. HPLC analysis showed that 9-HPODE [(9S)-hydroperoxy-(10E,12Z)-octadecadienoic acid], a compound found in oxLDL, was reduced to 9-HODE [(9S)-hydroxy-(10E,12Z)-octadecadienoic acid] in the presence of H2S. Thus H2S may act as an antiatherogenic agent by reducing LOOHs to the less reactive LOHs and could abrogate the pathobiological activity of oxLDL.


Subject(s)
Hydrogen Sulfide/pharmacology , Lipid Peroxides/metabolism , Lipoproteins, LDL/metabolism , Analysis of Variance , Cells, Cultured , Chromatography, High Pressure Liquid , Dose-Response Relationship, Drug , Endothelial Cells/cytology , Endothelial Cells/drug effects , Endothelial Cells/metabolism , Gene Expression Regulation, Enzymologic/drug effects , Heme Oxygenase-1/genetics , Humans , Linoleic Acids/metabolism , Linoleic Acids, Conjugated/metabolism , Malondialdehyde/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Thiobarbituric Acid Reactive Substances/metabolism , Time Factors
20.
Fortschr Neurol Psychiatr ; 77(2): 102-4, 2009 Feb.
Article in German | MEDLINE | ID: mdl-19221973

ABSTRACT

Recurrent disturbances of vision associated with headaches are typical signs of a migraine. A 15-year-old girl suffered from common migraine. The patient had a headache and nausea five days after a first and proved intake of LSD. Shortly later, a complete blindness of both eyes developed within seconds. These symptoms continued for 48 hours. As the pupillar reactions were intact the findings were consistent with cortical blindness. MRI and MR-angiography of the brain, analysis of the cerebrospinal fluid and blood investigations for thrombophilia were normal. The EEG showed a bilateral symmetrical delta wave slowing over the occipital areas. Within the following three months the girl had three more episodes with complete blindness over a period of 12-36 hours. There have never been any visual disturbances in between the episodes and afterwards. Extended diagnosis with long term blood pressure measurement, Doppler sonography and visual evoked potentials were normal. The occipital slowing in the EEG persisted for 18 months. As the symptoms were unusually long and severe for a complicated migraine it is possible that the temporary blindness was the correlate of flash backs caused by the LSD. LSD intake could trigger additional, local cortical dysfunction (e. g. in the occipital areas) in preexisting migraine.


Subject(s)
Blindness, Cortical/chemically induced , Hallucinogens/adverse effects , Lysergic Acid Diethylamide/adverse effects , Adolescent , Electroencephalography , Evoked Potentials, Visual/physiology , Female , Humans , Magnetic Resonance Angiography , Magnetic Resonance Imaging , Migraine Disorders/complications , Recurrence
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