| 1. |
- Magnuson, K., et al.
(författare)
-
Structural changes in the rat tympanic membrane following repeated pressure loads
- 2004
-
Ingår i: European Archives of Oto-Rhino-Laryngology. - 0937-4477 .- 1434-4726. ; 252:2, s. 76-82
-
Tidskriftsartikel (refereegranskat)abstract
- Healthy adult laboratory rats were exposed to alternating negative pressure and atmospheric pressure to replicate the clinical situation found in patients with chronic sniffing habits and chronic middle ear disease. The rats were placed in a box in which the pressure changed at intervals of 30 s between atmospheric pressure and a negative pressure of -3 kPa. This was repeated continuously or periods of 3 and 7 days. At completion of the experimental period, all rats had a normal otomicroscopic status. However, histological studies demonstrated that the pars flaccida was wrinkled and the loose connective tissue contained large fibroblasts with their long axes lying in a disorganized manner. The cells of the keratinizing epithelium were thicker than normal and mitoses were seen. Epithelial crypts filled with keratin were numerous along the epithelium. In the pars tensa, all layers were thicker than normal. These findings demonstrate that repeated pressure loading can create structural changes in the tympanic membrane. © 1995 Springer-Verlag.
|
|
| 2. |
- Adnane, Bouchaib, et al.
(författare)
-
Mid/far-infrared detection using a MESFET with B-modulation doped Ge-dot/SiGe-well multiple stacks in the channel region
- 2004
-
Konferensbidrag (refereegranskat)abstract
- Multiple modulation-doped Ge-dot/SiGe-QW stack structures were grown using MBE, and processed as FET devices for mid/far infrared detection. From a non-optimized device, a broadband photoresponse has been observed in the mid-infrared range of 3-15 μm. A peak responsivity was estimated to be as high as 100 mA/W at T= 20 K. This work indicates that SiGE QD/QW structures using the lateral transport geometry can be a potential candidate for photodetectors operating in far-infrared range.
|
|
| 3. |
- Fransén, Karin, 1973-, et al.
(författare)
-
Polymorphism in the retinoic acid metabolizing enzyme CYP26B1 and the development of Crohn's disease
- 2013
-
Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 8:8, s. e72739-
-
Tidskriftsartikel (refereegranskat)abstract
- Several studies suggest that Vitamin A may be involved in the pathogenesis of inflammatory bowel disease (IBD), but the mechanism is still unknown. Cytochrome P450 26 B1 (CYP26B1) is involved in the degradation of retinoic acid and the polymorphism rs2241057 has an elevated catabolic function of retinoic acid, why we hypothesized that the rs2241057 polymorphism may affect the risk of Crohn's disease (CD) and Ulcerative Colitis (UC). DNA from 1378 IBD patients, divided into 871 patients with CD and 507 with UC, and 1205 healthy controls collected at Örebro University Hospital and Karolinska University Hospital were analyzed for the CYP26B1 rs2241057 polymorphism with TaqMan® SNP Genotyping Assay followed by allelic discrimination analysis. A higher frequency of patients homozygous for the major (T) allele was associated with CD but not UC compared to the frequency found in healthy controls. A significant association between the major allele and non-stricturing, non-penetrating phenotype was evident for CD. However, the observed associations reached borderline significance only, after correcting for multiple testing. We suggest that homozygous carriers of the major (T) allele, relative to homozygous carriers of the minor (C) allele, of the CYP26B1 polymorphism rs2241057 may have an increased risk for the development of CD, which possibly may be due to elevated levels of retinoic acid. Our data may support the role of Vitamin A in the pathophysiology of CD, but the exact mechanisms remain to be elucidated.
|
|
| 4. |
|
|
| 5. |
- Kovacsovics, Bea, et al.
(författare)
-
MRI screening of the cerebellopontine angle and inner ear with fast spin-echo T2 technique
- 2000
-
Ingår i: Archives Italiennes de Biologie. - 0003-9829. ; 138:1, s. 87-92
-
Tidskriftsartikel (refereegranskat)abstract
- In patients with unilateral hearing loss and dizziness it is important to rule out a cerebellopontine angle process. This is often done by audiological and otoneurological investigations. However, in many cases we must rely on the imaging of the temporal bone and the cerebello-brainstem area. The paper has presented the three dimensional (3D) Fast Spin-Echo (FSE) T2 weighted, 0.7 mm thick MR images, which in addition to being quick, does not require the use of expensive contrast material. Between September 1996 and November 1997, 152 patients with unilateral hearing loss and/or balance disorders were investigated. In normal cases the 7th and 8th nerves could be followed accurately from the brainstem to the internal auditory meatus. The found tumors were hypointense compared to the cerebrospinal fluid and could be outlined with reasonable accuracy even without gadolinium contrast. The inner ear had high signal, like cerebrospinal fluid. The patency of the cochlea could be estimated accurately. Thus, 3D FSE T2 weighted images can reliably differentiate between patients with and without pathologies of the cerebellopontine angle. The use of gadolinium contrast could be avoided in most of the cases, but contrast is necessary for differential diagnostic purposes in patients with alterations in the cerebellopontine angle or in doubtful cases.
|
|
| 6. |
- Persson, Pekka, et al.
(författare)
-
Using the glasgow benefit plot as a prognostic instrument and for preoperative counseling in patients with otosclerosis
- 2007
-
Ingår i: Otology and Neurotology. - 1531-7129 .- 1537-4505. ; 28:6, s. 739-744
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: The Glasgow Benefit Plot (GBP) is a graph showing the pure-tone thresholds preoperatively and postoperatively, and is meant to visualize the possible outcome of binaural hearing for individual patients. We used our database comprising a large number of patient data to test the usefulness of the GBP. STUDY DESIGN: Evaluation based on retrospective clinical data. SETTING: Tertiary referral center, University clinic. MAIN OUTCOME MEASURES: Audiometric assessment included bilateral preoperative and postoperative evaluation using conventional audiometry. Three preoperative groups (unilateral, asymmetric, and symmetric hearing impairment) were split into 6 postoperative categories in the GBP diagram. RESULTS: Considering the 509 operations, including 34 bilateral operations, the total outcome was distributed as follows: 34% resulted in bilateral normal hearing, 24% unilateral normal hearing (in operated ear), 14% still unilateral hearing impairment (in operated ear), 13% symmetric hearing impairment, 10% asymmetric hearing impairment (operated ear best), 5% still asymmetric hearing impairment (nonoperated ear best). The distribution of outcomes depended in part on the bone conduction level in the operated ear and in part on the hearing status in the contralateral ear. CONCLUSION: The GBP is a useful instrument that provides a means for judging the binaural hearing status. However, the outcome of stapes surgery for individual persons and for a group depends critically on the preoperative audiometric criteria for patients who are chosen for surgery. In cases of depressed bone conductions, the method does not indicate the upper limit for possible hearing improvement. A number of patients with combined hearing impairments were included in the present study population. In preoperative counseling, the GBP must be complemented with information with regard to the limitation of possible hearing improvement owing to the individual bone conduction level.
|
|
| 7. |
- Westerberg, J, et al.
(författare)
-
Ten-year myringoplasty series: does the cause of perforation affect the success rate?
- 2011
-
Ingår i: JOURNAL OF LARYNGOLOGY AND OTOLOGY. - : Cambridge University Press. - 0022-2151 .- 1748-5460. ; 125:2, s. 126-132
-
Tidskriftsartikel (refereegranskat)abstract
- Objective: To present the results of primary myringoplasty procedures together with the perforation cause, perforation size and site, surgeons experience, and surgical method, and to investigate how these factors relate to graft take rates. Study design: Retrospective chart review of 243 consecutive patients undergoing primary myringoplasty with temporalis fascia underlay over a 10-year period from 1994 to 2004. Results: The overall graft take rate was 95 per cent. The retroauricular approach resulted in a 97 per cent graft take rate, whereas a significantly lower rate (77 per cent) was seen for surgery conducted via the endaural approach, or via an ear speculum. There was no relationship between other factors and tympanic membrane healing. Conclusion: No association was found between perforation cause and graft take rate. The underlay technique is safe and reliable, and the retroauricular approach is preferable as it enables good surgical access and has better results.
|
|
| 8. |
- Zetterström, Karin, et al.
(författare)
-
Being born small for gestational age increases the risk of severe pre-eclampsia
- 2007
-
Ingår i: British Journal of Obstetrics and Gynecology. - : Wiley. - 1470-0328 .- 1471-0528. ; 114:3, s. 319-324
-
Tidskriftsartikel (refereegranskat)abstract
- Objective: The first aim of this study was to investigate the risk of pre-eclampsia, both mild and severe, in women born small for gestational age (SGA). The second aim was to investigate whether the risk is modified by pre-eclampsia in the previous generation. Design: Population-based cohort study. Setting: Sweden. Population: A population of 118 634 women registered both as newborns and as mothers in the Swedish Medical Birth Register of 1973-2003. Of these, 6883 had been born SGA. Only primiparas and singletons were included. Methods: The pregnancies that the women were born out of were analysed with regard to presence of pre-eclampsia, while their own pregnancies were analysed regarding age at delivery, smoking, body mass index and incidence of mild or severe pre-eclampsia. Multiple logistic regression analysis was used. In a first step, we adjusted for maternal characteristics, and in a second step, for pre-eclampsia in the previous generation. Main outcome measures: Odds ratio for mild and severe pre-eclampsia. Results: In women born SGA, the adjusted odds ratio (first step) for mild pre-eclampsia was 1.19 (95% CI 1.03-1.38), while for severe pre-eclampsia it was 1.69 (95% CI 1.40-2.02) compared with those not born SGA. After the second-step adjustment, the odds ratio for mild pre-eclampsia was 1.16 (95% CI 1.00-1.35) and for severe pre-eclampsia was 1.62 (95% CI 1.35-1.95). No statistically significant effect modification from pre-eclampsia in the previous generation was shown. Conclusions: Women born SGA suffer a markedly increased risk of severe pre-eclampsia. Exposure to pre-eclampsia during a woman's own fetal development significantly increases her risk of pre-eclampsia but does not modify the SGA effect.
|
|
