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Willgerodt H, Keller E, Bennek J, Emmrich P. Diagnostic Value of Fine-Needle Aspiration Biopsy of Thyroid Nodules in Children and Adolescents. J Pediatr Endocrinol Metab 2006; 19:507-516. [PMID: 38742785 DOI: 10.1515/jpem-2006-190408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2023]
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Pavlovic J, Kaufmann F, Boltshauser E, Capone Mori A, Gubser Mercati D, Haenggeli CA, Keller E, Lütschg J, Marcoz JP, Ramelli GP, Roulet Perez E, Schmitt-Mechelke T, Weissert M, Steinlin M. Neuropsychological problems after paediatric stroke: two year follow-up of Swiss children. Neuropediatrics 2006; 37:13-9. [PMID: 16541363 DOI: 10.1055/s-2006-923932] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
AIM The aim of this study was to obtain information about neurological and cognitive outcome for a population-based group of children after paediatric ischaemic stroke. METHODS Data from the Swiss neuropaediatric stroke registry (SNPSR), from 1.1.2000 to 1.7.2002, including children (AIS 1) and neonates (AIS 2). At 18-24 months after a stroke, a follow-up examination was performed including a history, neurological and neuropsychological assessment. RESULTS 33/48 children (22 AIS 1, 11 AIS 2) participated in the study. Neurological outcome was good in 16/33. After childhood stroke mean IQ levels were normal (94), but 6 children had IQ < 85 (50-82) and neuropsychological problems were present in 75%. Performance IQ (93) was reduced compared to verbal IQ (101, p = 0.121) due to problems in the domain of processing speed (89.5); auditory short-term memory was especially affected. Effects on school career were common. Outcome was worse in children after right-sided infarction. Children suffering from stroke in mid-childhood had the best prognosis. There was no clear relationship between outcome and localisation of the lesion. After neonatal stroke 7/11 children showed normal development and epilepsy indicated a worse prognosis in the remaining 4. CONCLUSION After paediatric stroke neuropsychological problems are present in about 75% of children. Younger age at stroke as well as an emergence of epilepsy were predictors for worse prognosis.
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Keller E, Krayenbühl N, Bjeljac M, Yonekawa Y. Cerebral vasospasm: results of a structured multimodal treatment. ACTA NEUROCHIRURGICA. SUPPLEMENT 2005; 94:65-73. [PMID: 16060243 DOI: 10.1007/3-211-27911-3_11] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Symptomatic cerebral vasospasm (CVS) with delayed ischemic neurologic deficits affects about one third of the patients after aneurysmal subarachnoid hemorrhage (SAH). In spite of the lack of definite evidence of large clinical trials, the devastating outcome of the natural history of symptomatic CVS demands an aggressive CVS treatment in a practically oriented, structured multimodal treatment regimen. With our treatment protocol good functional outcome could be reached in 66% of the patients with symptomatic CVS. This policy requires close and fast multidisciplinary collaboration between neurosurgeons, neuroradiologists, competent in endovascular interventions, and specialists for neurointensive care. We report on our experience with 79 cases with symptomatic CVS and delayed ischemic neurologic deficit (DIND) after aneurysmal SAH. The different treatment options with CVS are reviewed and practical guidelines for a step by step treatment are given.
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Keller BPJA, Lubbert PHW, Keller E, Leenen LPH. Tissue-interface pressures on three different support-surfaces for trauma patients. Injury 2005; 36:946-8. [PMID: 16023909 DOI: 10.1016/j.injury.2004.09.017] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2003] [Revised: 09/10/2004] [Accepted: 09/10/2004] [Indexed: 02/02/2023]
Abstract
The purpose of this study was to evaluate and compare tissue-interface pressures on three different support-surfaces for trauma patients. The support-surfaces were a semi soft overlay mattress, a vacuum mattress and a spine board. Tissue-interface pressures were measured in a standardised way between the scapulae, the sacrum, the heels and the different support-surfaces in 20 healthy volunteers. Appreciation of comfort of the support-surface was assessed using a 10-point visual analog scale. High and potentially ischaemic interface pressures were found on all three support-surfaces, with the highest pressures (exceeding 170 mmHg) measured on the spine board. The spine board got the worst comfort score. It was also noted that no support was given to the normal lumbar lordosis by the spine board. There is a need for new support-surfaces for trauma patients, which reduce interface pressures and are comfortable.
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Douville V, Keller E, Lambertz K, Lodi A, Miller JHM. The control of impurities in chlortalidone using a reversed-phase stationary phase. PHARMEUROPA SCIENTIFIC NOTES 2005; 2005:5-10. [PMID: 17687887] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
A reversed-phased liquid chromatographic method for the control of impurities of nine impurities in Chlortalidone drug substance is presented. The method is sufficiently sensitive to quantify down to the level of 0.0015 per cent equivalent to a concentration of 15 microg/ml.
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Kiess W, Kratzsch J, Keller E, Schneider A, Raile K, Klammt J, Seidel B, Garten A, Schmidt H, Pfäffle R. Clinical examples of disturbed IGF signaling: intrauterine and postnatal growth retardation due to mutations of the insulin-like growth factor I receptor (IGF-IR) gene. Rev Endocr Metab Disord 2005; 6:183-7. [PMID: 16151622 DOI: 10.1007/s11154-005-3049-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Töro K, Hubay M, Sótonyi P, Keller E. Fatal traffic injuries among pedestrians, bicyclists and motor vehicle occupants. Forensic Sci Int 2005; 151:151-6. [PMID: 15939146 DOI: 10.1016/j.forsciint.2005.01.014] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2003] [Accepted: 01/26/2005] [Indexed: 10/25/2022]
Abstract
The objective of this study was to investigate characteristic injuries of pedestrians and bicyclists (unprotected) compared to motor vehicle occupants' (protected) in fatal traffic accidents. Cases of 664 fatal traffic accidents (371 pedestrians, 45 bicyclists, and 248 motor vehicle occupants) were collected from 1999 to 2001 using the database of the Forensic Institute in Budapest. Autopsy reports were analyzed. Location of injuries, blood alcohol levels, seasonal distribution and natural diseases influencing accident outcome were evaluated. For statistical analysis, odds ratio (OR) with 95% confidence interval (CI) was used by a conditional logistic regression. There were substantial differences in distribution of injuries suffered by pedestrians, bicyclists and motor vehicle occupants. Among pedestrians and bicyclists there was a higher rate of head injuries, such as skull fractures, epidural haemorrhage, subdural haemorrhage, brain contusion, and injuries of the lower extremities. Thoracic damages, such as traumatic aortic rupture, hemothorax, and abdominal damages, like liver rupture were dominant in motor vehicle occupants. Considering existing natural diseases, coronary artery disease was the only one with higher occurrence among motor vehicle occupants 24 (9.7%) compared with pedestrians and bicyclist 36 (8.6%). These results underline the importance of preventive strategies in transportation, pointing out that different methods are necessary to reduce fatal injuries of various traffic participants.
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Steinlin M, Pfister I, Pavlovic J, Everts R, Boltshauser E, Capone Mori A, Gubser Mercati D, Hänggeli CA, Keller E, Luetschg J, Marcoz J, Ramelli GP, Roulet Perez E, Schmitt-Mechelke T, Weissert M. The first three years of the Swiss Neuropaediatric Stroke Registry (SNPSR): a population-based study of incidence, symptoms and risk factors. Neuropediatrics 2005; 36:90-7. [PMID: 15822021 DOI: 10.1055/s-2005-837658] [Citation(s) in RCA: 131] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
We report the results of three years of the population-based, prospective Swiss NeuroPaediatric Stroke Registry (SNPSR) of children (up to 16 years) with childhood arterial ischaemic stroke (AIS1), neonatal stroke (AIS2), or symptomatic sinus venous thrombosis (SVT). Data on risk factors (RF), presentation, diagnostic work-up, localisation, and short-term neurological outcome were collected. 80 children (54 males) have been included, 40 AIS1, 23 AIS2, and 17 SVT. The data presented will be concentrated on AIS. The presentation for AIS1 was hemiparesis in 77% and cerebellar symptoms and seizures in 20%, respectively. AIS2 presented in 83% with seizures and in 38% with abnormality of muscle tone. Two or more RF were detected in 54%, one RF in 35%. The most prominent RF for AIS1 were infections (40%), followed by cardiopathies and coagulopathies (25% each). AIS2 were frequently related to birth problems. Neurological outcomes in AIS1 and AIS2 were moderate/severe in 45 % and 32 %, respectively. The outcome correlated significantly with the size of infarction (p = 0.013) and age at stroke (p = 0.027). The overall mortality was 6%. Paediatric stroke is a multiple risk problem, which leads to important long-term sequelae.
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Horn LC, Limbach A, Hoepffner W, Tröbs RB, Keller E, Froster UG, Richter CE, Jakubiczka S. Histologic analysis of gonadal tissue in patients with Ullrich-Turner syndrome and derivative Y chromosomes. Pediatr Dev Pathol 2005; 8:197-203. [PMID: 15747103 DOI: 10.1007/s10024-004-1013-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2004] [Accepted: 11/10/2004] [Indexed: 12/20/2022]
Abstract
To identify patients who had Ullrich-Turner syndrome (UTS) and were at risk for gonadoblastoma or associated germ cell tumors, molecular genetic analysis was carried out to detect Y chromosomal sequences. From peripheral blood samples of 5 patients who had cytogenetically confirmed UTS, genomic DNA was extracted and screened for Y chromosomal sequences by polymerase chain reaction. The morphology of the gonadal tissues was compared with results from polymerase chain reaction. Three phenotypic females showed UTS mosaicism with normal X chromosome accompanied by Y chromosomal material, and 2 patients showed marker chromosomes. Molecular analysis represented loci PABY, SRY, ZFY, TSPY, DYZ3, DYZ1 DXYS, 19Y, DYS-273, DYS-148, DYS218, DYS224, and DYZ1. Three patients showed gonadal tumors (1 with unilateral gonadoblastoma, 1 with unilateral dysgerminoma, and 1 patient had both tumors in 1 gonad). Molecular genetic screening for Y chromosomal sequences may be useful as an additional tool for the identification of patients at risk for a gonadal tumor. Careful, complete processing, including step sectioning, of the gonadectomy specimens to detect small lesions is recommended.
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Kademani D, Lewis J, Lamb D, Keller E, Koka S, Harmsen S. Loco-regional predictors for failure of early stage (T1&T2) nomo intraoral squamous cell carcinoma. Int J Oral Maxillofac Surg 2005. [DOI: 10.1016/s0901-5027(05)81228-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Keller E, Pangalu A, Fandino J, Könü D, Yonekawa Y. Decompressive craniectomy in severe cerebral venous and dural sinus thrombosis. ACTA NEUROCHIRURGICA. SUPPLEMENT 2005; 94:177-83. [PMID: 16060260 DOI: 10.1007/3-211-27911-3_28] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
OBJECTIVE To evaluate the outcome of patients with most severe cerebral venous and dural sinus thrombosis (CVT) after decompressive craniectomy. Indications and techniques for decompressive craniectomy and intensive care regimen are discussed. METHODS Between 2000 and 2004 15 patients with CVT and intracerebral hemorrhage were treated at the Department of Neurosurgery, University Hospital Zurich. Among them, four patients with the most severe illness course were treated with decompressive craniectomy. Indications for decompressive craniectomy were deterioration of level of consciousness with CT signs of space occupying brain edema, venous infarction and congestional bleeding with mass effect, midline shift and obliteration of the basal cisterns. RESULTS Among 15 patients with CVT and intraparenchymatous hemorrhage four patients were treated with decompressive craniectomy. Glasgow Coma Scale (GCS) immediately before the operation was in mean 10.2 (range 6 to 13). No patient showed signs of unilateral or bilateral third nerve palsy before surgery. No surgical complications were observed. All four patients who underwent decompressive craniectomy recovered with favourable functional outcome (Glasgow Outcome Scale; GOS 4 and 5). Anticoagulation therapy with heparin was reconvened 12 hours postoperatively with half dosage and 12 hours later with full dosage. No enlargement of existing intraparenchymatous hematoma or other intracranial bleeding complications occurred. CONCLUSIONS Favorable functional outcome in selected patients with most severe courses of CVT can be achieved after decompressive craniectomy. Postoperative anticoagulation therapy with full dose heparin 24 hours after craniotomy seems to be safe. Precise indications and techniques for combined surgical decompression and thrombectomy deserve to be evaluated in future studies.
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Keller E. Stereotransparente Kristallstrukturen. Von G. Harsch und R. Schmidt. Rudolf Schmidt, 3D-Technik für Lehre und Forschung, Darmstadt 1983. 38 Transparente, Textblätter, Tasche mit 30 Betrachtungsbrillen, komplett DM 440,-. CHEM UNSERER ZEIT 2004. [DOI: 10.1002/ciuz.19840180306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Mavenyengwa M, Keller E, Munyombwe T. Seroprevalence of leptospiral antibodies in commercial pigs in the Mashonaland East Province of Zimbabwe. ACTA ACUST UNITED AC 2004. [DOI: 10.4314/zvj.v30i3.5349] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Muroi C, Yonekawa Y, Khan N, Rousson V, Keller E. Seasonal variations in hospital admissions due to aneurysmal subarachnoid haemorrhage in the state of Zurich, Switzerland. Acta Neurochir (Wien) 2004; 146:659-65. [PMID: 15197608 DOI: 10.1007/s00701-004-0278-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
INTRODUCTION In clinical practice, the occurrence of aneurysmal subarachnoid haemorrhage (SAH) often coincides with a particular season. Our objective was to examine seasonal variations in hospital admissions due to aneurysmal SAH. METHODS The study population consisted of 489 patients with aneurysmal SAH who were admitted to the Department of Neurosurgery, University Hospital of Zurich, Switzerland, between 1st of January 1996 and 31st of December 2002. Statistical significance of seasonal variation was determined by applying Roger's r test. RESULTS Statistically significant seasonal variation was only found among patients younger than 60 years, showing a first peak in spring and second lower peak in autumn (Roger's r=6.89, p<0.05). A borderline significance was found in men younger than 60 years (Roger's r=5.96, p=0.051). A trend was observed in patients presenting with Fisher grade 1-2 (Roger's r=5.70, p=0.058). CONCLUSIONS Previous studies from different countries have shown significant seasonal variations, with the peak period for aneurysmal SAH differing widely. There appears to be some link between aneurysmal SAH and the season of the year or variations in weather conditions. Further investigations are desirable to evaluate which weather or climatic parameters correlate well with SAH.
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Tröbs RB, Hoepffner W, Bühligen U, Limbach A, Keller E, Schütz A, Horn LC, Kiess W, Bennek J. Video-assisted gonadectomy in children with Ullrich Turner syndrome or 46,XY gonadal dysgenesis. Eur J Pediatr Surg 2004; 14:179-84. [PMID: 15211408 DOI: 10.1055/s-2004-815870] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Patients with dysgenetic gonads carry a high risk for the development of gonadal neoplasia. The aim of the study is to evaluate indications and feasibility of laparoscopy and video-assisted prophylactic gonadectomy in children with Ullrich Turner syndrome (UTS) or 46,XY gonadal dysgenesis (GoDy). Between 1996 and December 2002 five girls with UTS and nine patients with 46,XY GoDy (female gender role) were explored by laparoscopy. Video-assisted salpingo-oophorectomy or gonadectomy was performed using a three-port technique. Prophylactic salpingo-oophorectomy was exclusively performed in UTS patients with proven presence of translocated parts of the Y chromosome. In three patients with 46,XY GoDy laparoscopy was followed by surgical revision of the groin and open gonadectomy in four patients. In two cases with UTS the removed streak gonads contained small unilateral tumours stage pT1a, and in four cases of 46, XY GoDy histopathological investigation revealed bilateral neoplasms stage pT1b. We found the following tumour types: gonadoblastoma, dysgerminoma, testicular intraepithelial neoplasia, and mature teratoma. In conclusion, investigative laparoscopy gives a good image of the internal genital structures and allows the safe removal of the dysgenetic gonads during the same operation. The high rate of gonadal tumours underlines the indication for early gonadectomy in these patients.
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Böttner A, Keller E, Kratzsch J, Weigel J, Keller A, Blum WF, Kiess W, Pfäffle R. PROP1 mutations cause progressive failure of anterior pituitary function including adrenal insufficiency. Exp Clin Endocrinol Diabetes 2004. [DOI: 10.1055/s-2004-819105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Kratzsch J, Gerber M, Seidel B, Böttner A, Keller E, Thiery J, Kiess W. Resistin has different molecular isoforms in human circulating blood. Exp Clin Endocrinol Diabetes 2004. [DOI: 10.1055/s-2004-819219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Schmitz C, Keller E, Freuding T, Silny J, Korr H. 50-Hz magnetic field exposure influences DNA repair and mitochondrial DNA synthesis of distinct cell types in brain and kidney of adult mice. Acta Neuropathol 2004; 107:257-64. [PMID: 14689206 DOI: 10.1007/s00401-003-0799-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2003] [Revised: 11/04/2003] [Accepted: 11/04/2003] [Indexed: 10/26/2022]
Abstract
Despite several recent investigations, the impact of whole-body magnetic field exposure on cell-type-specific alterations due to DNA damage and DNA repair remains unclear. In this pilot study adult mice were exposed to 50-Hz magnetic field (mean value 1.5 mT) for 8 weeks or left unexposed. Five minutes after ending exposure, the mice received [(3)H]thymidine and were killed 2 h later. Autoradiographs were prepared from paraffin sections of brains and kidneys for measuring unscheduled DNA synthesis and mitochondrial DNA synthesis, or in situ nick translation with DNA polymerase-I and [(3)H]dTTP. A significant (P<0.05) increase in both unscheduled DNA synthesis and in situ nick translation was only found for epithelial cells of the choroid plexus. Thus, these two independent methods indicate that nuclear DNA damage is produced by long-lasting and strong magnetic field exposure. The fact that only plexus epithelial cells were affected might point to possible effects of magnetic fields on iron transport across the blood-cerebrospinal fluid barrier, but the mechanisms are currently not understood. Mitochondrial DNA synthesis was exclusively increased in renal epithelial cells of distal convoluted tubules and collecting ducts, i.e., cells with a very high content of mitochondria, possibly indicating increased metabolic activity of these cells.
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Flacke S, Urbach H, Block W, Träber F, Mürtz P, Keller E, Hartmann A, Schild HH. Perfusion and molecular diffusion-weighted MR imaging of the brain: in vivo assessment of tissue alteration in cerebral ischemia. Amino Acids 2004; 23:309-16. [PMID: 12373552 DOI: 10.1007/s00726-001-0143-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The combined use of perfusion imaging (PI) and diffusion-weighted imaging (DWI) is opening a new window into the processes that occur during the first hours of ischemia. DWI detects changes in molecular diffusion associated with cytotoxic edema. PI characterizes the degree of regional hypoperfusion. Regions showing mismatches between DWI and PI, i.e. hypoperfused areas with normal diffusion behavior are considered potentially salvageable. We present results of 11 patients with an occlusion of the middle cerebral artery stem and spontaneous stroke evolution. Whereas the infarct was clearly visible on initial DWI and PI, surrounding tissue at risk of infarction was marked in all patients by an increased blood volume and transit time, but only in a subgroup (n = 3) where alteration were more pronounced this tissue at risk was progressively infarcted. These human DWI and PI data show alterations in the area of tissue at risk which correlates with infarct progression.
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Zastrow O, Seidel B, Kiess W, Thiery J, Keller E, Böttner A, Kratzsch J. The soluble leptin receptor is crucial for leptin action: evidence from clinical and experimental data. Int J Obes (Lond) 2004; 27:1472-8. [PMID: 14634677 DOI: 10.1038/sj.ijo.0802432] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE The soluble leptin receptor (sOB-R) was recently identified as the main leptin-binding protein in human blood. The aim of our study was to elucidate the effects of physiologically relevant amounts of sOB-R on leptin-induced proliferation in a cell model. SUBJECTS AND MEASUREMENTS To determine molar ratios between sOB-R and leptin in vivo, we measured both parameters in the serum of 529 healthy children and adolescents. For our in vitro cell model, mouse pre-B cells, transfected with the long form of the murine leptin receptor (BAF3/L46), were incubated with recombinant human leptin at two different basal levels (0.5 and 0.1 nM) and with the sOB-R at varying levels. The proliferative response of the cells was quantified by a (3)H-thymidine uptake assay. RESULTS Significantly higher molar sOB-R/leptin ratios were observed during the first years of life, up to a 7.67-fold excess of sOB-R (quartiles: 4.43/10.27) in boys, compared to the states of prepuberty and puberty. An up to 10-fold molar excess of the sOB-R, reflecting the in vivo situation, resulted in a significant suppression of leptin action in the cell model. In contrast, gradually decreasing ratios of lower than two, as calculated during the progression of childhood and in early puberty, corresponded to proliferative rates in vitro as determined at basal leptin concentrations. CONCLUSION At a distinct molar excess, sOB-R may suppress leptin action through inhibition of specific leptin binding to membrane-bound receptors in vitro. In vivo, sOB-R may further function to delay leptin clearance and increase the available leptin pool in the circulation. In the case of a massive excess of sOB-R, is it likely to be inhibitory to leptin interaction with the tissue membrane-bound OB-R.
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Müller G, Keller A, Reich A, Hoepffner W, Kratzsch J, Buckler JM, Kiess W, Keller E. Priming with testosterone enhances stimulated growth hormone secretion in boys with delayed puberty. J Pediatr Endocrinol Metab 2004; 17:77-83. [PMID: 14960025 DOI: 10.1515/jpem.2004.17.1.77] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND AND OBJECTIVE Tests for growth hormone (GH) deficiency are not always helpful in the differential diagnosis of physiological delay of growth and puberty and GH deficiency. PATIENTS AND METHODS To enhance diagnostic specificity, we used a single dose testosterone priming before repeating the arginine stimulation test in 26 boys with short stature and only early signs of puberty who failed to show an adequate response of serum GH in the first test. RESULTS 77% (20/26 patients) increased their serum GH peak to more than 10 ng/ml, whereas six patients were still below this concentration. CONCLUSION We propose that testosterone priming is a useful tool to distinguish between physiological delay of growth and puberty and GH deficiency and should be included in the diagnostic procedure.
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Hügle B, Döllmann R, Keller E, Kiess W. Addison's crisis in adolescent patients with previously diagnosed diabetes mellitus as manifestation of polyglandular autoimmune syndrome type II--report of two patients. J Pediatr Endocrinol Metab 2004; 17:93-7. [PMID: 14960027 DOI: 10.1515/jpem.2004.17.1.93] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
We report on two female adolescents--both diagnosed with type 1 diabetes mellitus in early childhood--who presented with signs of severe metabolic decompensation. In both cases recompensation was difficult, and during the stay in hospital increasing discoloration of palmar creases was observed. ACTH testing demonstrated cortisol deficiency in both patients. In addition, autoimmune thyroiditis was diagnosed in one patient. As a polyglandular autoimmune syndrome was suspected, autoantibody studies were performed and the presence of autoantibodies against thyroid and adrenal tissue was established. Polyglandular autoimmune syndrome (PGA) type II can lead to subsequent manifestation of deficiencies of several endocrine glands. Although PGA type II usually presents at a more advanced age, adolescents may also present with the full spectrum of the disease. Especially in the presence of Addison's disease, life-threatening situations can develop rapidly. Coloration of palmar skin creases of patients with known type I diabetes mellitus should serve as a warning sign to be followed up with investigation of endocrine functions.
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Keller E, Nadler A, Niederer P, Yonekawa Y, Imhof HG. A new subdural probe for combined intracranial pressure (ICP) and cerebral blood flow (CBF) monitoring. Acta Neurochir (Wien) 2003; 145:1111-5; discussion 1115. [PMID: 14663569 DOI: 10.1007/s00701-003-0102-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2003] [Revised: 01/01/2003] [Accepted: 01/01/2003] [Indexed: 10/26/2022]
Abstract
We report the development of a new subdural probe for combined intracranial pressure (ICP) and cerebral blood flow (CBF) monitoring with near infrared spectroscopy (NIRS) and indocyanine green (ICG) dye dilution. For NIRS a conventional subdural ICP monitoring probe was supplied with two fiber bundles and 90-degree prisms. Injections of 25 mg ICG were performed. Regional values for the mean transit time of ICG (rmtt(ICG)), cerebral blood flow (rCBF) and cerebral blood volume (rCBV) were calculated. With prototypes of the probe in two patients with intracerebral haemorrhage 18 comparative measurements obtained simultaneously with conventional NIRS (optodes placed on the skin) and the subdural NIRS probe were performed. The new subdural NIRS probe allows combined monitoring of ICP and cerebral hemodynamics in the brain directly, without the influence of extracerebral tissue.
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