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J Kraus

Publications and source records attributed to J Kraus.

At least 19 recordsLinked to original sources
PubMed2006

Behaviour of human heterochromatic regions during the synapsis of homologous chromosomes.

BACKGROUND: Alterations of synapsis can disturb or arrest meiosis and result in infertility. Synaptic abnormalities are frequently observed in infertile patients but also in fertile men. METHODS: The subtelomere-specific multiplex fluorescence in-situ hybridization (stM-FISH) has been applied in combination with immunofluorescence to identify all synaptonemal complexes (SCs) and to analyse those presenting synaptic anomalies in fertile and infertile men. RESULTS: SCs with heterochromatin blocks other than centromere (noncentromeric heterochromatin) presented a higher frequency of gaps (SC discontinuities) and splits (unsynapsed SC regions) at pachytene, the incidences for 9qh, 1qh, 15p and 21p being the highest ones. Inter-individual variability in the incidence of synaptic anomalies in these regions has been observed. In addition, synaptic anomalies in other SC regions are more frequent in infertile cases than in controls. Clear association of the SC15 and SC21 to the XY pair has been seen. CONCLUSION: Noncentromeric heterochromatic regions are the last to synapse. The inter-individual variation observed in the incidence of gaps and splits in these regions may be explained by the heteromorphism of these regions in the general population. The presence of synaptic anomalies in other SC regions may indicate nuclei with a severely affected synapsis. Noncentromeric heterochromatic regions might play a role in the association of autosomal SC15 and SC21 with the XY pair.

Centromere↗
PubMed2006

Crossover frequency and synaptonemal complex length: their variability and effects on human male meiosis.

In this study, immunocytogenetics has been used in combination with the subtelomere-specific multiplex-fluorescent in-situ hybridization (stM-FISH) assay to identify 4681 autosomal synaptonemal complexes (SCs) of two fertile men. Comparisons of crossover maps for each individual SC between two men with extremely different meiotic crossover frequencies show that a low crossover frequency results in (i) a higher frequency of XY pairs and of small SCs without MLH1 foci and (ii) lower frequency of crossovers in the proximity of centromeres. In both cases, the bivalents which most frequently lacked MLH1 foci were the XY pair and the SC21. Analysis of SC length showed that SC arms can be longer or shorter than the corresponding mitotic one. Moreover, for a given SC, the variation in length found in one arm was independent of the variation observed in the other one (e.g. SC1p arms are longer than SC1q arms). The results confirmed that reduction in the crossover frequency may increase the risk of achiasmate small bivalents and that interindividual differences in crossover frequency could explain the variability in the frequencies of aneuploidy in human sperm. How MLH1 foci are positioned within the SC is discussed based on detailed MLH1 foci distributions and interfoci distances. Finally, evidence that the variation of the SC arm length may reflect the abundance of open and of compact chromatin fibers in the arm is shown.

Chromosome Mapping↗
PubMed2006

A systematic review of brain injury epidemiology in Europe.

BACKGROUND: The world's literature on traumatic brain injury (TBI) grows annually including new reports on epidemiologic findings from many regions. With the wide variety of reports emphasizing various factors it is useful to compile these findings, hence the objective of this report. Thus, we describe epidemiological factors from European studies largely published in the last 20 years. METHOD: The Medline was searched for TBI related articles from about 1980 to 2003 including terms such as "epidemiology", "head injury", "brain injury" and others. From the research reports identified, we checked references for additional relevant reports and from those reports we abstracted data on TBI incidence, severity, external cause, gender, mortality, prevalence, cost and related factors. RESULTS: Twenty three European reports met inclusion criteria and included findings from national studies from Denmark, Sweden, Finland, Portugal, Germany, and from regions within Norway, Sweden, Italy, Switzerland, Spain, Denmark, Ireland, the U.K. and France. An aggregate hospitalized plus fatal TBI incidence rate of about 235 per 100,000 was derived. Prevalence rate data were not reported from any European country. An average mortality rate of about 15 per 100,000 and case fatality rate of about 11 per 100 were derived. The TBI severity ratio of hospitalized patients was about 22:1.5:1 for mild vs. moderate vs. severe cases, respectively. The percentages of TBI from external causes varied considerably and several reports reported an association of alcohol use with TBI. Outcome or disability findings were mixed and inconsistent. INTERPRETATION: It was difficult to reach a consensus on all epidemiological findings across the 23 published European studies because of critical differences in methods employed across the reports. We highly recommend the development of research guidelines to standardize definitional, case finding, and data reporting parameters to help establish a more precise description and hence utility of the epidemiology of TBI in Europe.

Brain Injuries↗
PubMed2006

Clinical and neuroimaging features of severely brain-injured patients treated in a neurosurgical unit compared with patients treated in peripheral non-neurosurgical hospitals.

Most European TBI patients are managed in peripheral hospitals without benefit of guidelines for transfer of such patients to neurosurgical units as needed. This report compares clinical features and outcomes in two series of severe TBI patients: those admitted to a neurosurgical centre or to a general hospital, all in the Piedmont Region of Italy. Of 630 patients with a GCS of 3-8, 351 were admitted to a centralized neurosurgical unit, and 279 were admitted and treated at a peripheral hospital. All patients had a CT scan read by a neurosurgeon on duty and were classified using the Marshall criteria as having a diffuse injury or non-surgical mass lesions. Outcomes were assessed between 6 months and 6 years using either the GOS Extended or the GOS. Independent variables were age, sex, GCS score and Marshall classification. All the examined factors were significantly different between the two groups (p<0.001). For patients admitted to the neurosurgical centre, age, Marshall classification of the CT and GCS were predictors of a favourable outcome, while for patients treated in general hospitals, Marshall classification of the CT, gender and age were predictors of a favourable outcome. Patients admitted to neurosurgical centres are different from those treated in general hospitals not having these specialized facilities and personnel. The absence of guidelines for the transfer of these patients for more advanced care are lacking and should be the focus of new studies on patient referral.

Adolescent↗
PubMed2005

[Severe necrotizing pancreatitis during pregnancy].

A case report of 28-year-old pregnant women (34 week of pregnancy) with acute pancreatitis is presented. Likely cause of pancreatitis in the patient was extreme combined hyperlipidemia. The subject underwent seven complicated surgeries and with a necessity of prolonged intensive post-operative care. A year apart from the episode of acute pancreatitis both the patient and her baby are doing well. Pancreatic function has been restored and plasma lipid levels are, with appropriate medication, within normal ranges. Analysis of the problematic the relationship between hypertriglyceridemia, pregnancy and acute pancreatitis.

Adult↗
PubMed2004

[Chronic upper abdominal pain without improvement after using proton pump inhibitors].

HISTORY AND CLINICAL FINDINGS: A 57-year-old woman was admitted to our hospital because of relapsing, therapy-resistant pain, predominantly in the upper abdomen. The symptoms began 6 years previously, after a resection of parts of the small intestine for an ileus of unclear cause. Subsequently 11 (!) gastroscopies showed repeatedly gastritis and Helicobacter pylori- negative gastric and/or small intestinal ulcers which were treated with proton pump inhibitors. This led to no significant improvement of the complaints and produced no healing. DIAGNOSTIC FINDINGS AND THERAPY: Gastroscopy showed, at the transition of the gastric fundus to the corpus, an area with multiple, fibrin coated ulcers. Histologically an active, chronic gastric ulcer was seen, with perifocally dense inflammatory infiltration by predominantly eosinophils. In the colon these histological findings, although clearly less pronouncedly, were also seen i.e. an eosinophilic gastroenteropathy. This was initially treated with 60 mg/day prednisone. Under this treatment she became completely symptom-free. After a dose reduction to 5 mg prednisone daily the symptoms occurred again. Thereupon long-term immunosuppressive therapy with 100 mg azathioprine daily was introduced. Regular clinical and endoscopic monitoring showed a complete remission of the ulcers and no complaints after 1.5 years. CONCLUSION: Our case report shows that in patients with uncharacteristic abdominal pain and gastric ulcers, which improve inadequately under the usual medication such as proton pump inhibitors, less common illnesses must be considered. Despite the rarity of eosinophilic gastroenteropathy the exact (histological) diagnosis plays an important role, because a specific therapy with corticosteroids and/or azathioprine can induce improvement of the symptoms.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed2004

Accelerated kindling development in mu-opioid receptor deficient mice.

The relevance of mu-opioid systems for central excitability and kindling related disturbed learning performance was underlined by investigations using mu-opioid receptor knockout mice. Mice lacking mu-opioid receptors showed an accelerated kindling development induced by the convulsant drug pentylenetetrazol. Blockade of delta-opioid receptors by naltrindole suppressing kindling development in wild-type animals led to a further acceleration of kindled seizure development in the knockout mice. Mice lacking mu-opioid receptors showed such a low learning performance in the shuttle box, that the kindling induced learning deficit as seen in wild-type mice was not detected. The results were discussed on the basis of receptor binding studies with regard to subtypes of glutamatergic receptors, delta-opioid and somatostatin receptors. An increase in glutamate and somatostatin binding could contribute to the enhanced excitability in the-mu-opioid receptor knockout mice.

Animals↗
PubMed2004

CD45RA+ ICAM-3+ lymphocytes in interferon-beta1b-treated and -untreated patients with relapsing-remitting multiple sclerosis.

OBJECTIVES: Multiple sclerosis (MS) is believed to be an autoimmune disease of the human central nervous system mediated by autoreactive T cells. Interferon-beta1b (IFN-beta1b) has been shown to be effective in reducing disease activity defined by clinical and magnetic resonance imaging (MRI) criteria in relapsing-remitting MS (RRMS). Yet, the exact mechanisms by which these benefits are achieved remain unknown. CD45RA is a marker for naive T lymphocytes and intercellular adhesion molecule-3 (ICAM-3) is expressed on resting lymphocytes. MATERIAL AND METHODS: Forty-eight patients with RRMS, 24 of them treated with recombinant IFN-beta1b and 24 untreated, were enrolled in this prospective study over 18 months. We investigated the percentage of CD45RA+ ICAM-3+ cells within the total lymphocyte subset in the peripheral blood serially every 3 months and in CSF once at baseline. Detailed clinical examination including Expanded Disability Status Scale (EDSS) score was performed every 3 months and cranial MRI scans were assessed every 6 months. RESULTS: We found a temporary increase in the CD45RA+ ICAM-3+ lymphocyte ratio in peripheral blood of both untreated and IFN-beta1b-treated RRMS patients. Moreover, we determined a significant negative correlation (r = -0.5874; P < 0.01) between age as well as the EDSS score (r = -0.3629; P < 0.05) and the percentages of CD45RA+ ICAM-3+ lymphocytes in peripheral blood but a positive correlation between EDSS score and the CD45RA+ ICAM-3+ ratio (r = 0.3913; P < 0.05) in the CSF at baseline. CONCLUSION: CD45RA+ ICAM-3+ lymphocyte ratio in peripheral blood might indicate immunosenescence in MS. However, from our data it cannot be finally concluded whether it is also influenced by IFN-beta1b treatment.

Adjuvants, Immunologic↗
PubMed2004

Characterization of all human male synaptonemal complexes by subtelomere multiplex-FISH.

During meiotic prophase I, homologous chromosomes synapse and recombine. Both events are of vital importance for the success of meiosis. When homologous chromosomes synapse, a proteinaceous structure called synaptonemal complex (SC) appears along the pairing axis and meiotic recombination takes place. The existence of immunolabeling techniques for SC proteins (SCP1, SCP2 and SCP3) and for DNA mismatch repair proteins present in late recombination nodules (MLH1) allow analyses of both synapsis and meiotic recombination in the gametocyte I. In situ hybridization methods can be applied afterwards because chromatin is preserved during cell fixation for immunoanalysis. The combination of both methodologies allows the analysis of synapsis and the creation of recombination maps for each bivalent. In this work we apply the seven-fluorochrome subtelomere-specific multiplex FISH assay (stM-FISH) to human male meiotic cells previously labeled by immunofluorescence (SCP1, SCP3, MLH1, CENP) to assess its utility for human SC karyotyping. This FISH method consists of microdissected subtelomeric probes labeled combinatorially with seven different fluorochromes. Results prove its usefulness for the identification of all human SCs. Furthermore, by labeling subtelomeric regions this one-single-step method enables the characterization of interstitial and terminal SC fragments and SC delineation even if superposition is present in pachytene spreads.

Cytogenetic Analysis↗
PubMed2004

Our surgical experience with large vestibular schwannomas.

Our aim is to remove large vestibular schwannomas (VS) radically with minimal morbidity. Usually, these tumours cannot not be treated by irradiation. In the years 1997-2003, 69 VS were operated in the Department of Otorhinolaryngology, Head and Neck Surgery of the First Medical Faculty in Prague, Czech Republic. Prevailing majority of these tumours were of the 4th grade (House classification), compressing the brainstem. Six patients in the group suffered from neurofibromatosis 2, in five cases the patients were indicated for neurosurgery due to rapid tumour growth after previous irradiation. All tumours were radically removed using a retromastoid osteoplastic and translab approach with an intraoperative nerve monitoring. Good function of the facial nerve was achieved in 90%. The nerve had to be resutured in 4 cases with consequent satisfactory results, cross anatomosis was not performed. Hearing function was preserved in 8% of patients only. In 6 patients with neurofibromatosis 2, the auditory brainstem implant (ABI) was used to preserve hearing. This study demonstrates that a radical removal of large vestibular schwannomas is possible using a minimally invasive surgical technique and peroperative nerve monitoring with a good impact on quality of life. Auditory brainstem implants bring a new chance of hearing after tumour removal in patients with NF2.

Adult↗
PubMed2003

[Use of the auditory brainstem neuroprosthesis in the Czech Republic].

BACKGROUND: Auditory brainstem implant (ABI) is an electroprosthetic device enabling sound sensations in deaf persons with a bilateral lesion of auditory nerves. Stimulation of auditory nuclei in the floor of the IVth ventricle is realized by an electrode array introduced during surgery in the lateral recess of the IVth ventricle. METHODS AND RESULTS: The main indication group for ABI is represented by patients with neurofibromatosis 2 (NF2) suffering from bilateral vestibular schwannomas. During surgery aimed at tumour removal, auditory nerve function and integrity are almost always destroyed, therefore, an ABI can be introduced as an one stage procedure. Implantees use the device mainly as the aid in lipreading, only very rarely they can comprehend speech without visual cues. Auditory brainstem implant programme has been introduced in the Czech Republic in the year 1999. It was the very first ABI surgery in the Central Europe. Since that time, 5 patients had received the auditory brainstem implant, from which the first four use the device for a longer time. CONCLUSIONS: The last operated patient has not been activated yet. It may be said, that ABI represents a benefit to all our patients, in one implanted this benefit is significant, since he can understand speech without lipreading, the other implantees use the device as an aid in lipreading. In one female patient, the device benefit is severely limited by a motoric handicap after partial cerebellar resection during surgery. Nevertheless, she uses the implant on a daily basis, but contact with her is limited and difficult.

Adult↗
PubMed2003

[Cervical myelopathy induced by calcium pyrophosphate tophus in primary chondrocalcinosis].

A 78 year old female patient with cervical myelopathy induced by a calcium pyrophosphate dihydrate tophus around the dens axis with clinical signs of a cervical tumor is presented. After operation of the tumor, the diagnosis of a generalized CPPD disease was established retrospectively, where by patient had complained of joint pain already for many years. This known complication of a primary chondrocalcinosis should be a reason for a careful investigation of the cervical spine in CPPD disease, because neurological disturbances might increase the joint destruction in the manner of "Charcot joints".

Aged↗
PubMed2003

Combined p53/Bax mutation results in extremely poor prognosis in gastric carcinoma with low microsatellite instability.

Gastric cancer is highly refractory to DNA-damaging therapies. We therefore studied both gene mutation and protein expression of p53 and Bax in a cohort of 116 patients with gastric cancer who underwent R0-resection with a curative intent. Bax mutation was independent from severe microsatellite instability (MSI), that is, global mismatch repair deficiency as determined by analysis of BAT-25/BAT-26 microsatellite markers. Thus, Bax-frameshift mutation is a feature of tumors with low MSI. In contrast and as expected, no p53 mutations were observed in the microsatellite instable tumors. p53 Mutation or p53 overexpression did not have an impact on disease prognosis. p53-Inactivation was, however, associated with an extremely poor prognosis in the subgroup of patients with Bax-mutated tumors. Thus, we show for the first time that the combined mutation of p53 and Bax, two key regulators of the mitochondrial apoptosis pathway, results in an extremely aggressive tumor biology and poor clinical prognosis.

Apoptosis↗
PubMed2003

Effect of Italy's motorcycle helmet law on traumatic brain injuries.

OBJECTIVES: To evaluate the impact of a revised Italian motorcycle-moped-scooter helmet law on crash brain injuries. DESIGN: A pre-post law evaluation of helmet use and traumatic brain injury (TBI) occurrence from 1999 to 2001. SETTING: Romagna region, northeastern Italy, with a 2000 resident population of 983 534 persons. PARTICIPANTS: Motorcycle-moped rider survey for helmet use compliance and all residents in the region admitted to the Division of Neurosurgery of the Maurizio Bufalini Hospital in Cesena, Italy for TBI. OUTCOME MEASURES: Helmet use compliance and change in TBI admissions and type(s) of brain lesions. RESULTS: Helmet use increased from an average of less than 20% to over 96%. A comparison of TBI incidence in the Romagna region shows that there was no significant variation before and after introduction of the revised helmet law, except for TBI admissions for motorcycle-moped crashes where a 66% decrease was observed. In the same area TBI admissions by age group showed that motorcycle mopeds riders aged 14-60 years sustained significantly fewer TBIs. The rate of TBI admissions to neurosurgery decreased by over 31% and epidural hematomas almost completely disappeared in crash injured moped riders. CONCLUSIONS: The revised Italian mandatory helmet law, with police enforcement, is an effective measure for TBI prevention at all ages.

Accidents, Traffic↗