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71.
Brain-derived neurotrophic factor (BDNF) and neurotrophin 3 (NT-3) mRNAs are expressed in developing and adult rodent tongue and are important for the proper development of lingual gustatory and somatosensory innervation in rodents. Here, we wished to determine whether the findings in rodents apply to humans. By using in situ hybridization histochemistry, distinct, specific, and in some instances overlapping patterns of BDNF and NT-3 mRNA expression were found in the developing and adult human tongue, gustatory papillae, and taste buds. BDNF mRNA was expressed in the superior surface epithelium of the developing fungiform papillae (i.e., developing taste buds), in the epithelium covering the circumvallate papillae, and in the subepithelial mesenchyme. Interestingly, BDNF mRNA was expressed in the lingual epithelium before nerve fibers reached the epithelium, indicating a prespecialization of the gustatory epithelium before the arrival of nerves. In the adult fungiform papillae, BDNF mRNA labeling was found in taste buds and in restricted areas in the non-gustatory lingual epithelium. NT-3 mRNA was found in the developing lingual epithelium and gustatory papillae. NT-3 mRNA labeling was observed in the adult fungiform taste buds, overlapping with BDNF mRNA labeling, in contrast to what was seen in rodents. NT-3 mRNA was additionally found in restricted areas in filiform papillae. Protein gene product 9.5 (PGP) antibodies were used to investigate a possible correlation between lingual innervation and sites of neurotrophin gene activity. Adult human tongue innervation differed from that of rodents, possibly in part due to a different neurotrophin expression pattern in the human tongue. Based on these findings, we suggest that BDNF and NT-3 are important for the initiation and maintenance of the gustatory and somatosensory innervation also in humans. The broader and somewhat overlapping expression patterns of BDNF and NT-3 mRNAs, compared with rodents, suggest additional and possibly somewhat overlapping roles for BDNF and NT-3 in the human tongue and also indicate differences between species. It is important that interspecies differences be taken into consideration. 相似文献
72.
Achim Langenbucher Sven Reese Christina Jakob Berthold Seitz 《Ophthalmic & physiological optics》2004,24(5):450-457
PURPOSE: To investigate the pseudophakic accommodation effect in dual and mono optic translation accommodative intraocular lenses (AIOL) using linear matrix methods in the paraxial space. METHODS: Dual (anterior optic of power +32 D linked to a compensatory posterior optic of negative power) and mono lens power was determined in the non-accommodated state using linear geometric optics based on the Gullstrand model eye. The position of the AIOL was calculated from a regression formula. Pseudophakic accommodation was assessed with three systems: (1) forward shift of the mono optic lens, (2) anterior translation of the anterior optic in the dual optic lens system with an unchanged position of the posterior minus lens and (3) symmetrical anterior and posterior translation of the anterior and posterior lens. The Gullstrand model eye was modified by changing the axial length (and proportionally changing the phakic anterior chamber depth) to investigate the accommodative effect in myopic and hyperopic eyes. RESULTS: The dual optic lens system (2) yields a nearly constant accommodation amplitude of 2.4-2.5 D mm(-1) movement over the total range of axial lengths. The mono optic lens (1) provides a higher accommodative effect only in extremely short eyes (high refractive power of the lens), whereas for normal eyes (1.4-1.5 D mm(-1) movement) and for long (myopic) eyes the accommodative effect is much less than the dual optic lens. The dual optic lens system under condition (3) yields less accommodation amplitude compared with the dual optic system under condition (2) over the total range of axial length but provides higher accommodation amplitude compared with the mono optic lens system (1) with axial lengths greater than 22.3 mm (lens power 25.5 D). In the accommodated state, with lens translation of 1 mm, the absolute value of the lateral magnification increases with the refractive power of the mono optic lens (1) and decreases in both dual optic lens systems (under conditions 2 and 3). CONCLUSIONS: A mathematical strategy is presented for calculation of the accommodative effect of mono-optic and dual optic AIOL. The dual optic lens yielded a nearly constant accommodation amplitude of about 2.4-2.5 D mm(-1) translation, whereas the mono optic lens yielded an accommodative response of <2 D mm(-1) translation in long myopic or normal eyes. Only in extremely short eyes is the accommodative amplitude of the mono-optic lens higher than the dual optic lens. 相似文献
73.
Thomas Elter Peter Borchmann Holger Schulz Marcel Reiser Sven Trelle Roland Schnell Markus Jensen Peter Staib Timo Schink?the Hartmut Stützer Jürgen Rech Martin Gramatzki Walter Aulitzky Ibrahim Hasan Andreas Josting Michael Hallek Andreas Engert 《Journal of clinical oncology》2005,23(28):7024-7031
PURPOSE: To determine the efficacy and safety of a newly developed concomitant administration of fludarabine and alemtuzumab (FluCam) in patients with relapsed or refractory B-cell chronic lymphocytic leukemia (B-CLL). PATIENTS AND METHODS: A total of 36 patients were treated in this phase II study (median age, 61.47 years; mean number of prior chemotherapies, 2.6; Binet stage C, n = 28). After an initial dose escalation of alemtuzumab over 3 days, alemtuzumab 30 mg and fludarabine 30 mg/m2 were administered on 3 consecutive days. Treatment was repeated after 28 days for up to six cycles. Restaging (following National Cancer Institute criteria) was carried out after cycles 2 and 4 and 1 month after the end of treatment. RESULTS: The overall response rate was 83% (11 complete responses, 19 partial responses, one stable disease, and five progressive diseases). Two patients with progressive disease developed fungal pneumonias, and one patient died as a result of Escherichia coli sepsis. Two subclinical cytomegalovirus reactivations occurred. CONCLUSION: The new FluCam regimen is effective and feasible in patients with relapsed and refractory B-CLL. 相似文献
74.
Michael Patrick Lux Sven Ackermann Mayada R Bani Caroline Nestle-Kr?mling Timm O Goecke Dieter Niederacher R Bodden-Heidrich Hans-Georg Bender Matthias Wilhelm Beckmann Peter Andreas Fasching 《European journal of cancer prevention》2005,14(6):503-511
INTRODUCTION: Some 5-10% of all cases of breast cancer and ovarian cancer have a hereditary genesis. In the setting of an interdisciplinary cancer genetics clinic, a study of the age at which patients first take advantage of early cancer detection (ECD) facilities was conducted in order to assess the influence of familial risk on health issues. METHODS: The study included 556 women who fulfilled the inclusion criteria (IC) for genetic analysis of the BRCA1 and BRCA2 genes, as well as 205 who did not meet these criteria but attended the primary consultation. RESULTS: Consulters who met the inclusion criteria took advantage of nearly all methods of ECD at an earlier time than women who did not. A comparison of consulters with or without breast cancer showed that those without breast cancer participated in all methods of ECD at an earlier time. CONCLUSION: Methods of improving and increasing participation in ECD facilities, and of encouraging women who are at risk to start on such programs at a younger age, need to be discussed. In this study, familial risk already resulted in a younger age of uptake of ECD facilities. 相似文献
75.
Duveken B.Y. Fontein Willemien van de WaterJ. Sven D. Mieog Gerrit-Jan LiefersCornelis J.H. van de Velde 《European journal of surgical oncology》2013
Neoadjuvant chemotherapy (NAC) is an increasingly important component in the treatment of both locally advanced and early-stage breast cancer. With this, a debate on the timing of the sentinel lymph node biopsy (SLNB) has emerged. At the end of the last century, the SLNB was introduced as an axillary staging modality, and this paper aims to further elucidate this issue in the context of NAC. We compiled available data on the SLNB after NAC and provide clinical guidance for timing the SLNB in this context. On the basis of our findings, we recommend that the SLNB can be performed after NAC in all cases. In patients with a clinically node-negative (cN0) status prior to NAC, the SLNB should be performed after NAC, and in case of a histologically confirmed negative SLNB, a completion axillary lymph node dissection (ALND) has no added value and can be omitted. In patients with clinically positive nodal involvement (cN+) prior to NAC, all axillary surgery can also be performed after NAC. 相似文献
76.
Elisabet K. Lidbrink Sven A. T rnberg Edward M. Azavedo Jan O. Frisell Marie-Louise Hjalmar Karin S. Leifland Tor B. Sahlstedt Lambert Skoog 《Acta oncologica (Stockholm, Sweden)》1994,33(4):353-358
This presentation describes the organization and first-round results of the Stockholm mass mammo-graphy screening program, and discusses ways of checking the quality of an ongoing screening program. The Stockholm mammography screening program started in 1989 at five independent screening units, and comprises more than 150 000 women aged 50 to 69 years. The first round was completed in June 1991. Compliance during the studied period was 70.6%, and the recall rate was 3.0% of the attending women. Breast cancer was diagnosed in 676 women, of whom 90 (13.3%) had a cancer in situ. The cancer prevalence rate was thus 6.3 cancers per 1 000 screened women. Surgery was performed on 925 women, of whom 249 had benign lesions, giving a benign/malignant ratio of 0.37 to 1. Fifty-two per cent of the cancer patients were operated with breast conserving surgery. The median size of the invasive cancers was 12 mm; almost 80% were node-negative. Experience from the first two years of this mass mammography screening program shows that it meets the major quality requirements. One of the main future goals is to maintain the high quality of the program. Another important goal is a further increase in compliance. 相似文献
77.
Igor O. Akimchenko Sven Rutkowski Tuan-Hoang Tran Gleb E. Dubinenko Vsevolod I. Petrov Anna I. Kozelskaya Sergei I. Tverdokhlebov 《Materials》2022,15(22)
Recently, polyether ether ketone has raised increasing interest in research and industry as an alternative material for bone implants. This polymer also has some shortcomings, as it is bioinert and its surface is relatively hydrophobic, causing poor cell adhesion and therefore slow integration with bone tissue. In order to improve biocompatibility, the surface of polyether ether ketone-based implants should be modified. Therefore, polished disc-shaped polyether ether ketone samples were surface-modified by direct current magnetron sputtering with ultrathin titanium and zirconium coatings (thickness < 100 nm). The investigation results show a uniform distribution of both types of coatings on the sample surfaces, where the coatings mostly consist of titanium dioxide and zirconium dioxide. Differential scanning calorimetry revealed that the crystalline structure of the polyether ether ketone substrates was not changed by the coating deposition. Both coatings are amorphous, as shown by X-ray diffraction investigations. The roughness of both coating types increases with increasing coating thickness, which is beneficial for cell colonization. The coatings presented and investigated in this study improve wettability, increasing surface energies, in particular the polar component of the surface energies, which, in turn, are important for cell adhesion. 相似文献
78.
Markus Keller Norbert Peter Cora M. Holicki Anna V. Schantz Ute Ziegler Martin Eiden Dorian D. Drge Andreas Vilcinskas Martin H. Groschup Sven Klimpel 《Viruses》2022,14(11)
Unlike farm animals, wild animals are not subject to continuous health surveillance. Individual projects designed to screen wildlife populations for specific pathogens are, therefore, also of great importance for human health. In this context, the possible formation of a reservoir for highly pathogenic zoonotic pathogens is a focus of research. Two of these pathogens that have received particular attention during the last years are the novel severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2), due to its fast global spread and high impact to the human health, and, since its introduction into Germany, the flavivirus West Nile virus (WNV). Especially in combination with invasive vertebrate species (e.g., raccoons (Procyon lotor) and raccoon dogs (Nyctereutes procyonoides) in Germany), risk analysis must be done to enable health authorities to assess the potential for the establishment of new wild life reservoirs for pathogens. Therefore, samples were collected from raccoons and raccoon dogs and analyzed for the presence of SARS-CoV-2 and WNV infections in these populations. Molecular biological and serological data obtained imply that no SARS-CoV-2 nor WNV reservoir has been established in these two wild life species yet. Future investigations need to keep an eye on these invasive carnivore populations, especially since the close contact of these animals to humans, mainly in urban areas, would make animal–human transmission a challenge for human health. 相似文献
79.
Samantha Dequanter Ellen Gorus Sven Van Laere Nico De Witte Dominique Vert Iris Steenhout Maaike Fobelets Ronald Buyl 《European journal of ageing》2022,19(4):1135
Although research on sociodemographic correlates of internet use in older adults without and with pronounced cognitive impairment is already quite extensive, much less is known about the relationship between cognitive frailty (CF) and this behaviour. As CF is associated to multidimensional frailty aspects, this study explored the relationship between internet use and CF, operationalised as Subjective Cognitive Impairment, in older adults by means of a comprehensive explanatory model including sociodemographic factors and multiple frailty measures. The dataset included a sample of community-dwelling 60 + older adults that were included in the Belgian Ageing Studies (BAS) and that completed survey questions on (i) internet use frequency and (ii) internet activities. Multidimensional frailty was measured with the CFAI-Plus. The analysis comprised a structural equation modelling (SEM) procedure. Internet use was frequent; however, it became less frequent with higher CF. Moreover, the latter used less tablets as compared to the no-low CF group. Navigating the web, sharing email and online banking were the most frequently reported activities. Tele-communicating with Skype, online shopping and using e-government services were the least frequent. Age, female gender, lower income and living with a partner were also negatively associated with internet use. To conclude, CF, along with other frailty and sociodemographic factors, was negatively related to internet use in older adults. Future research should focus, amongst others, on the dynamic processes underlying internet use in the population of older adults affected by CF.Supplementary InformationThe online version contains supplementary material available at 10.1007/s10433-022-00686-2. 相似文献
80.
Elbieta Ciela Edyta Suliga Helena Kadu
kov Sven Michel Marcela Iov Viera Simo
kov Titus Martin Alexander Braun Dorota Kozie Stanisaw Guszek 《Nutrients》2022,14(22)
Purpose. The aim of this study was to assess the reproducibility and reliability of the KomPAN questionnaire among two groups of university students from Germany and Slovakia. Methods. A total of 422 individuals (mean age 21.4 years, SD 4.0), including 197 from Slovakia (men 26.2%) and 225 from Germany (men 22.3%), were tested using the self-administered (SA-Q) version of the KomPAN questionnaire and then retested two weeks later. A cross-classification analysis, kappa coefficients, Cronbach’s ɑ coefficients, and a test-retest result comparison were conducted separately for each group of students to assess the reproducibility and reliability of the questionnaire. Results. The cross-classification values were higher than 46.2% among the German students and higher than 55.8% among the Slovakian students. The kappa coefficients ranged from 0.21 to 0.90 in the German students and from 0.38 to 0.94 in the Slovakian students. Cronbach’s ɑ ranged from 0.58 to 0.78. Conclusion. The questionnaire displayed a moderate to very good reproducibility, which was slightly higher in the Slovakian group than in the German group. Therefore, the questionnaire can be recommended for further analysis and comparison of the dietary habits among Germans and Slovakians on a larger scale. 相似文献