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61.
Background
It has been hypothesized that prematurity and adjunctive neonatal care is 'a priori' a risk for disturbances of palatal and orofacial development which increases the need for later orthodontic or orthognathic treatment. As results on late consequences of prematurity are consistently contradictory, the necessity exists for a fundamental analysis of existing methodologies, confounding factors, and outcomes of studies on palatal development in preterm and low birthweight infants.Method
A search of the literature was conducted based on Cochrane search strategies including sources in English, German, and French. Original data were recalculated from studies which primarily dealt with both preterm and term infants. The extracted data, especially those from non-English paper sources, were provided unfiltered in tables for comparison (Parts 1 and 2).Results
Morphology assessment of the infant palate is subject to non-standardized visual and metrical measurements. Most methodologies are inadequate for measuring a three-dimensional shape. Several confounding factors were identified as causes contributing to disturbances of palatal and orofacial development.Conclusion
Taking into account the abovementioned shortcomings, the following conclusions may be drawn for practitioners and prospective investigators of clinical studies. 1) The lack of uniformity in the anatomical nomenclature of the infant's palate underlines the need for a uniform definition. 2) Metrically, non-intubated preterm infants do not exhibit different palatal width or height compared to matched term infants up to the corrected age of three months. Beyond that age, no data on the subject are currently available. 3) Oral intubation does not invariably alter palatal morphology of preterm and low birthweight infants. 4) The findings on palatal grooving, height, and asymmetry as a consequence of orotracheal intubation up to the age of 11 years are inconsistent. 5) Metrically, the palates of orally intubated infants remain narrower posteriorly, beginning at the second deciduous molar, until the age of 11 years. Beyond that age, no data on the subject are currently available. 6) There is a definite need for further, especially metrical, longitudinal and controlled trials on palatal morphology of preterm and low birthweight infants with reliable measuring techniques. 7) None of the raised confounding factors for developmental disturbances may be excluded until evident results are presented. Thus, early orthodontic and logopedic control of formerly premature infants is recommended up to the late mixed dentition stage. 相似文献62.
Joos GF Brusselle GG Van Hoecke H Van Cauwenberge P Bousquet J Pauwels RA 《Immunology and Allergy Clinics of North America》2005,25(3):597-612, vii-viii
Asthma and allergic rhinitis are both characterized by airway inflammation, and glucocorticosteroids form the cornerstone of their pharmacologic treatment. All patients with asthma should be prescribed rapid-acting inhaled beta2-agonists as needed to use as rescue therapy in case of symptoms. As soon as patients experience symptoms at least once a week, controller medications should be started on a daily basis to achieve and maintain control of their asthma. Intranasal corticosteroids are given as first-line therapy for moderate to severe persistent rhinitis. Depending on the dominant symptom, H1-antihistamines, decongestants, or ipratropium can be added after re-evaluation. 相似文献
63.
Ebach K Joos H Doose H Stephani U Kurlemann G Fiedler B Hahn A Hauser E Hundt K Holthausen H Müller U Neubauer BA 《Neuropediatrics》2005,36(3):210-213
Severe myoclonic epilepsy in infancy (SMEI), severe idiopathic generalized epilepsy of infancy (SIGEI) with generalized tonic clonic seizures (GTCS), and myoclonic astatic epilepsy (MAE) may show semiological overlaps. In GEFS+ families, all three phenotypes were found associated with mutations in the SCN1A gene. We analyzed the SCN1A gene in 20 patients with non-familial myoclonic astatic epilepsy -- including 12 probands of the original cohort used by Doose et al. in 1970 to delineate MAE. In addition, 18 patients with sporadic SIGEI -- mostly without myoclonic-astatic seizures -- were analyzed. Novel SCN1A mutations were found in 3 individuals. A frame shift resulting in an early premature stop codon in a now 35-year-old woman with a borderline phenotype of MAE and SIGEI (L433fsX449) was identified. A splice site variant (IVS18 + 5 G --> C) and a missense mutation in the conserved pore region (40736 C --> A; R946 S) were detected each in a child with SIGEI. We conclude that, independent of precise syndromic delineation, myoclonic-astatic seizures are not predictive of SCN1A mutations in sporadic myoclonic epilepsies of infancy and early childhood. 相似文献
64.
Familial ALS in Germany: origin of the R115G SOD1 mutation by a founder effect 总被引:1,自引:0,他引:1
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Niemann S Joos H Meyer T Vielhaber S Reuner U Gleichmann M Dengler R Müller U 《Journal of neurology, neurosurgery, and psychiatry》2004,75(8):1186-1188
Mutations in the gene encoding Cu/Zn superoxide dismutase (SOD1) account for approximately 20% of patients with familial amyotrophic lateral sclerosis (FALS). In this study, sequence analysis of exons 1-5 of SOD1 in a large German cohort with FALS was performed. Among 75 affected patients, who were not obviously related probands with a positive family history, nine had missense mutations in SOD1. Four of the nine probands carry the same R115G mutation in exon 4 of the SOD1 gene. Genotyping with markers from the SOD1 locus revealed a common haplotype and shared allelic characteristics in these patients. These findings suggest that the R115G mutation in the German population originates from a common founder. 相似文献
65.
BACKGROUND: Neutropenic patients often develop bacterial or fungal infections not responding to broad-spectrum antibacterial or antifungal agents. Clinical efforts were made with transfusion of granulocyte concentrates; however, functions of granulocytes after multiple G-CSF stimulations and after apheresis are not yet investigated and described sufficiently. STUDY DESIGN AND METHODS: The aim of this study was to characterize functional and immunologic variables of granulocytes in blood samples drawn from donors before and after each stimulation episode with G-CSF, in the resulting granulocyte concentrates and in the patients 8 hours after transfusion. RESULTS: Chemotaxis was not influenced, neither by G-CSF application nor by apheresis. Multiple G-CSF stimulations enhanced oxidative burst and phagocytosis of Escherichia coli in donor granulocytes. These values returned to basal levels in granulocyte concentrates. Expression of granulocytic surface antigens was downregulated after application of G-CSF but returned to normal and in part enhanced values in concentrates. A clinically relevant increase of proinflammatory cytokines could not be detected. Leukotriene B4 production was reduced after the fourth G-CSF stimulation in the donor blood and enhanced in the granulocyte concentrate after apheresis. Results in recipients indicate that changes of granulocyte function noted in concentrates were only transient. CONCLUSION: Stimulation of healthy donors with repeated G-CSF injections and subsequent granulocyte apheresis does not dramatically change decisive functions of granulocytes. 相似文献
66.
van Herk M Witte M van der Geer J Schneider C Lebesque JV 《International journal of radiation oncology, biology, physics》2003,57(5):1460-1471
PURPOSE: We are developing a system to model the effect of random and systematic geometric errors on radiotherapy delivery. The purpose of this study was to investigate biologic and physical fractionation effects of random geometric errors and respiration motion and compare the resulting dose distributions with Gaussian blurring of the planned dose. MATERIALS AND METHODS: A hypothetical dose distribution with Gaussian penumbra was used. Random errors drawn from a normal distribution, optionally combined with simulated respiration motion (in the cranio-caudal direction), were used to displace the dose distribution for N simulated fractions. To simulate biologic effects of fractionation, the physical dose was converted to a biologically effective dose using the linear-quadratic model (including repopulation), then summed and converted back to physical dose for comparison. Differences between dose distributions were quantified in terms of the distance between selected isodose levels. RESULTS: A limited number of fractions led to an uncertainty in the position of isodose levels in the total dose with as standard deviation (SD) the SD of the random error divided by radical N. Due to biologic fractionation effects, the total dose distribution became slightly wider: 0.4 mm for alpha/beta = 1 Gy and a random error SD of 3 mm. The widening increased with random error and reduced with increasing alpha/beta but does not depend on the number of fractions or on repopulation. Respiration motion caused an asymmetric deviation in the shape of the total dose distribution, but no additional dose widening was seen from the biologic effect of fractionation. With a random error SD of 3 mm and respiration amplitude, A, of 1 cm or less (SD < 0.36 cm), the asymmetry was negligible. For larger respiration amplitudes (combined with the same random error), the shift of the 95% isodose level was about 0.25*A caudally, and 0.45*A cranially. CONCLUSIONS: Gaussian blurring with a combined SD of organ motion, setup error, and respiration motion is a valid approximation for the effect of purely random errors in fractionated radiotherapy. For respiration motion in excess of 1 cm in amplitude, isodose lines shift in a distinctly asymmetric fashion and asymmetric margins need to be used. 相似文献
67.
Handschel J Sunderkötter C Prott FJ Meyer U Kruse-Lösler B Joos U 《The Journal of pathology》2001,193(2):242-247
The purpose of this study was to describe the distribution patterns of various leukocyte subpopulations in the oral mucosa during the course of radiotherapy and to determine whether there are dose-dependent alterations, or any correlation between the clinical stages and the population density of specific leukocytes. The distribution and density of various leukocytes in oral mucosa in 13 head and neck cancer patients were immunohistochemically analysed before radiotherapy at 30 and 60 Gy and compared with the clinical degree of oral mucositis. Antibodies were used which characterized different subtypes of macrophages (27E10, 25F9, RM3/1) and recognized epitopes of granulocytes (CD15) and T cells (CD3, CD4, CD8). The study showed that whereas macrophages reactive with RM3/1 increased significantly at 30 Gy (p<0.01) and showed a further increase at 60 Gy (p<0.01), no significant alterations could be detected in the density of macrophages which stained positively for 27E10 or 25F9. Moreover, the percentage of macrophages reactive with RM3/1 showed a non-linear correlation with the clinical mucositis score (p<0.05). No significant alterations were detected in the percentage of T cells and granulocytes, compared with the values before radiotherapy. In conclusion, radiation-induced mucositis is characterized by features of an intermediate stage of an inflammatory response, suggesting active involvement of down-regulatory macrophages in its pathogenesis. 相似文献
68.
E. T. Peuker R. Werkmeister F. Pera U. Joos T. J. Filler 《Oral and maxillofacial surgery》2001,5(2):141-143
Methods: This study investigates whether human cadavers embalmed according to Thiel can be used for research and education in oral-maxillo-facial surgery. Different surgical approaches were tested on such cadavers. The usability of the specimen was judged jointly by anatomists and surgeons. Color, structure, and consistency of the different tissues were comparable to vital conditions. Thiel’s embalming technique applied to human cadavers provides an optimal basis for research and for basic and postgraduate medical education. 相似文献
69.
70.