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- Sundelin, Kaarina, 1967-
(författare)
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Head and Neck Cancer : Factors Affecting Tumour Growth
- 2007
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Head and neck cancer is the fifth most common cancer worldwide with an estimated annual global incidence of over 500 000 cases. These malignant tumours develop in the mucosal linings of the upper respiratory tract or in the salivary glands. The most common sites are in the oral cavity and larynx. Treatment modalities comprising surgery and chemoradiotherapy have improved significantly during the last 20 years, but not the long-term survival of patients. The aim of this thesis was to study the different factors affecting tumour growth in head and neck cancer that may have clinical implications in the future. Factors involving apoptosis, cell cycle activity, inflammation, and enzyme activity were of special interest.The results of the thesis indicate that patients with malignant salivary gland tumours having the lowest level of actively replicating cells have the best prognosis. The largest amount of replicating cells in tongue cancer specimens was found in the peripheral areas of tumour nests. Metallothionein, a protein that can hinder apoptosis, was found in excess in the same areas, whereas apoptosis activity was considerably lower. Taken together, these results indicate that the most aggressive cancer cells are found in the peripheral areas of tumours where apoptosis may be hindered.The expression of the death receptor Fas was higher in tongue cancer specimens than in normal mucosa. The expression of this receptor was studied further in two cell lines established from oral cancers. When a low dose of cisplatin was added to cell cultures, the Fas expression was enhanced in both cell lines and, furthermore, the Fas-induced apoptosis was increased in one of the cell lines. The results show that a common chemotherapeutic drug given in a low, less toxic dose may enhance receptor-mediated apoptosis of cancer cells.Malignant solid tumours are often distinguished by an increased proteolytic activity resulting in invasive growth, neo-angiogenesis, and metastases. This activity is conducted by enzymes that are secreted from tumour cells, or from normal cells in the tumour microenvironment. The regulation of enzyme secretion may be mediated by cytokines, small signalling molecules also present in cancer tissue. The results of this thesis show that two cytokines can synergistically induce enzyme secretion (matrix metalloproteinase-1 and -9) from oral cancer cells. Cytokine tumour necrosis factor-alpha and hepatocyte growth factor added alone to cell cultures strongly stimulated secretion of these enzymes. Thus, the tested cytokines, which are commonly secreted by fibroblasts and immune cells, may promote tumour growth.This thesis has contributed to an increased understanding of factors affecting tumour growth in head and neck cancer. The upcoming cancer therapies will be based on the increasing knowledge of these and other aberrant cellular mechanisms that may vary between different cancer forms.
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- Wadell, Karin, et al.
(författare)
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Group training in patients with COPD : long-term effects of decreased training frequency
- 2005
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Ingår i: Disability and Rehabilitation. - : Informa UK Limited. - 0963-8288 .- 1464-5165. ; 27:10, s. 571-581
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Tidskriftsartikel (refereegranskat)abstract
- Purpose.To investigate effects of decreased training frequency in patients with COPD. Methods.Forty-three COPD patients participated in a controlled study. The intervention group (30 patients) trained 3 times a week during 3 months and once a week during 6 months. Before, after 3 and 9 months all patients performed walking tests, cycle ergometer tests and responded questionnaires on health-related quality of life (HRQoL) (SGRQ, SF-36). Results.At 9 months compared to 3 months there were no changes in distance walked in the groups. Both groups decreased their VO2peak and the training group deteriorated in HRQoL. At 9 months compared to baseline the training group showed increased distance walked compared to the control group. In the disease-specific SGRQ the training group tended to improve their activity score while the control group tended to deteriorate in total score. In SF-36 the control group decreased their physical component score. Conclusion.Training once a week does not seem to be sufficient to maintain the level achieved after the 3-month period of training in COPD patients. However, training once a week during 6 months preceded by 3 months of high frequency training seems to prevent deterioration in physical capacity and HRQoL compared to baseline. Further studies are needed to investigate how to best sustain the benefits gained after physical training.
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3. |
- Wadell, Karin, et al.
(författare)
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Muscle performance in patients with chronic obstructive pulmonary disease : Effects of a physical training programme
- 2005
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Ingår i: Advances in Physiotherapy. - : Informa UK Limited. - 1403-8196 .- 1651-1948. ; 7:2, s. 51-59
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Tidskriftsartikel (refereegranskat)abstract
- The main aim was to evaluate how thigh muscle performance in patients with chronic obstructive pulmonary disease (COPD) is affected after a 3-month training programme. Another aim was to investigate if responders to training could be discriminated from non-responders. Thirty patients participated in high-intensity physical training in water or on land, three times per week, and 13 patients constituted a non-training control group. Maximal dynamic strength and endurance in thigh muscles were tested in an isokinetic dynamometer (KinCom) before and after training. At baseline, physical and pulmonary function were tested and used in the analysis of responders/non-responders. Maximal knee flexion strength improved in both training groups, whereas knee extension was improved in the land and control group. Sixty-four percent of all patients were not able to complete the muscle endurance test at baseline and no change was seen in muscle endurance after training within or between groups. A normal body mass index seemed to predict an improvement in muscle performance in responders. We conclude that physical training in water and on land is effective regarding maximal thigh muscle strength in COPD patients. BMI seems to be a discriminating factor for an increased muscle strength. Thigh muscle endurance was decreased in the majority of the patients and did not improve with the evaluated training programme.
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5. |
- Enberg, Birgit, 1956-
(författare)
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Work experiences among healthcare professionals in the beginning of their professional careers : a gender perspective
- 2009
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Swedish healthcare organizations have undergone substantial organizational and economic restructuring during the 1990s due to financial cutbacks. Little is known about recently graduated healthcare professionals´ work experience in healthcare and their future career preferences. The overall aims of this thesis was, to increase knowledge about how recently graduated healthcare professionals in Sweden perceive their work in healthcare organizations. A gender perspective is adopted. In this national cross-sectional study, four stratified random samples were separately drawn from the 1999 Swedish university graduates who were nurses (NS), occupational therapists (OT), physical therapists (PT) and (registered) physicians (PN) and who at the time of the sampling procedure were living in Sweden. Stratification was performed by sex. A total of 3989 were eligible and of those, 1434 were selected: 535 NS, 250 OT, 250 PT and 399 PN. A questionnaire was constructed containing questions about socio-demographic factors, working conditions, career preferences, work satisfaction and questions about the responsibility for and actual work with home and family, the so called unpaid household work. The questionnaires also contained questions measuring psychosocial working conditions: the effort-reward imbalance questionnaire (ERI-Q) and the demand-control questionnaire (DCQ). Collection of the data for NS, OT and PT was completed in March 2002 and for PN in May 2003. The response rate was 81% and 76% respectively. The total sample thus consists of 1145 participants; 423 nurses, 212 occupational therapists, 205 physiotherapists and 305 physicians. Most of the respondents were employed in the public sector, but many desired privately employment within the coming five year period, men more often than women. Career preferences for future work differed between women and men. A majority indicated that they did not have the opportunity to pursue knowledge development in the professional field during working hours and nearly one half could not work as independently as they wished. Satisfaction with work in general was high, but many were dissatisfied with management at work and a majority was dissatisfied with the work organization. This dissatisfaction was associated with the opportunity to work as independently as they wished and the opportunity to pursue knowledge development in the professional field. Significantly more women than men had the main responsibility for home and family and did most of the unpaid household work. Among the OT and PT working for county councils and municipalities, the results revealed that those working for municipalities, experienced low control at work compared with those working for county councils. No differences were found between OT and PT or between men and women in the two professions regarding the DCQ and the ERI-Q except for the WOC scale. Women had significantly higher scores on the WOC scale compared with men. Logistic regression analyses revealed a significant association between WOC and ERI, effort, reward and sex. One fourth of the OT and PT working for county councils and municipalities was dissatisfied with their job and this dissatisfaction was significantly associated with type of employer, reward and effort-reward imbalance (in the ERI-Q) and control (in the DCQ). Differences regarding scoring on the ERI-Q were found between nurses and physicians working in county councils but not between women and men in the same group, with the exception of the scores on overcommitment. Significantly more nurses were defined as having high effort, low reward and effort-reward imbalance compared with the physicians. More women in the NS and PN group were defined as experiencing WOC compared to men. Logistic regression analyses revealed significant associations between experiences of WOC and ERI, effort and reward. Nearly one fifth in the NS and PN group were dissatisfied with work and this dissatisfaction was particularly high among those with high effort, low reward, those with the greatest imbalance between effort and reward and those who experienced high overcommitment. In conclusion, in order to limit future work related problems and to be able to retain well educated professionals in healthcare work, dissatisfaction among the recently graduated must be taken seriously. Healthcare employers should better utilize the knowledge that recently graduated possess, regarding for example how to be a part of the development of the profession and the job. It is also important that healthcare employers address gender (in) equality at work and that work environments allow both women and men to combine careers with family duties.
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6. |
- Hirasawa, Karin, et al.
(författare)
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Utvärdering av uppsökande studie- och yrkesvägledning samt studie- och yrkesvägledning inom Arbetsforum Sydost
- 2006
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Syftet med denna rapport har varit att sammanställa de kunskaper och erfarenheter som finns från den uppsökande studie- och yrkesvägledningen, beskriva vad som har fungerat och vilka förutsättningar som behövs för verksamheten. Rapporten strävar efter att ge svar på följande frågor: Hur arbetar studievägledarna med att genomföra uppdraget? Vad är centralt i arbetet och vad kan utvecklas? Hur samarbetar olika yrkesgrupper med studie- och yrkesvägledarna? Vad kan utvecklas? Vilka förutsättningar är av betydelse för att den uppsökande studievägledningen/AFSO ska fungera? Resultatet av den uppsökande studievägledningen/AFSO – Nås målen för verksamheten?
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8. |
- Sundelin, Kaarina, et al.
(författare)
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Effects of cisplatin, interferon-alpha and 13-cis retinoic acid on the expression of Fas (CD95), intercellular adhesion molecule-1 (ICAM-1) and epidermal growth factor receptor (EGFR) in oral cancer cell lines
- 2007
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Ingår i: Journal of Oral Pathology & Medicine. - : Blackwell Publishing. - 0904-2512 .- 1600-0714. ; 36:3, s. 177-183
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Tidskriftsartikel (refereegranskat)abstract
- Background: Previous studies showed that many chemotherapeutic agents can induce immuno-suppression at therapeutic drug concentrations whereas low drug doses induce immuno-augmentation.Methods: The effect of low-dose cisplatin, interferon-alpha, and 13-cis retinoic acid on receptors involved in immune-mediated apoptosis (Fas/CD95), cell growth (epidermal growth factor receptor) and lymphocyte adhesion (intercellular adhesion molecule-1) was investigated in two oral cancer cell lines (UT-SCC-20A and UT-SCC-24A). Different methods for cell preparation were studied: mechanical and enzymatic detachment, and culture on chamber slides. Receptor expression was investigated using immunohistochemical staining. The amount of soluble and cell-bound Fas was determined with the ELISA technique, and the functional relevance of Fas expression, apoptosis induction, was analyzed.Results: Cisplatin enhanced cytoplasm and membrane staining for Fas in both cell lines. After cisplatin treatment, the amount of soluble Fas was increased in UT-SCC-20A cultures, but no effect was observed in the UT-SCC-24A cell line. Apoptosis, measured as enhanced caspase-3 activity, was induced by an agonistic Fas antibody (CH11) after cisplatin treatment in UT-SCC-24A cells.Conclusions: Low-dose cisplatin treatment enhanced Fas expression in both cell lines and increased susceptibility to apoptosis in one of them.
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9. |
- Sundelin, Kaarina, et al.
(författare)
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Effects of cytokines on matrix metalloproteinase expression in squamous cell carcinoma in vitro
- 2007
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Ingår i: Acta Oto-Laryngologica. - : Informa UK Limited. - 0001-6489 .- 1651-2251. ; 125:7, s. 765-773
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Tidskriftsartikel (refereegranskat)abstract
- Objective: MMPs play an important role in enhanced intra-tumoral proteolytic activity, promoting angiogenesis and invasion by acting on extracellular matrix substances. Cytokines secreted by tumour-infiltrating immune cells, fibroblasts and tumour cells can modulate MMP expression and secretion by cancer cells. The objective of this study was to investigate the effects of IL-6, soluble IL-6 receptor (sIL-6R), HGF, TNF- and IL-8 on MMP-1, -2 and -9 expression by two oral squamous cell carcinoma cell lines (UT-SCC-20A and -24A). Material and methods: ELISA was used to analyse secretion of total MMP protein and gelatin zymography was used for activity analysis. Results: IL-6 had a moderate stimulatory effect on MMP-1 secretion in both cell lines, whereas sIL-6R had no effect. When these cytokines were added together, a dose-dependent, synergistic stimulatory effect was observed. HGF also upregulated MMP-1 secretion, especially in one cell line (UT-SCC-24A), and a synergistic effect was observed when HGF was added to IL-6 in both cell lines. MMP-9 secretion by UT-SCC-24A was increased when stimulated with HGF and IL-6 combined with sIL-6R, whereas no effect was found in the other cell line. TNF- stimulated MMP-9 secretion in both cell lines, but only stimulated MMP-1 secretion in one (UT-SCC-24A). The zymographic results were consistent with the ELISA results, indicating an upregulation of active enzyme when a stimulatory effect on protein expression was detected. Conclusions: The intra-tumoral cytokines IL-6, hepatocyte growth factor (HGF) and tumour necrosis factor- (TNF-) stimulate oral cancer cells to enhanced secretion of matrix metalloproteinase (MMP)-1 and -9. These results contribute to an understanding of the extracellular events necessary for tumour progression.
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- Sundelin, Karin, et al.
(författare)
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Increased anterior chamber penetration of topical levofloxacin 0.5% after pulsed dosing in cataract patients.
- 2009
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Ingår i: Acta ophthalmologica. - : Wiley. - 1755-3768 .- 1755-375X. ; 87, s. 160-5
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: This study aimed to investigate the rise in aqueous humour (AH) levels of levofloxacin after a specific perioperative pulsed topical drop regimen. Methods: Thirty patients undergoing phacoemulsification surgery were administered two preoperative drops of levofloxacin 0.5%, 30 mins apart, and three pulsed drops postoperatively, 5 mins apart. Aqueous humour levels of levofloxacin were measured at the start of surgery and from 5 mins to 90 mins after the last postoperative drop. Samples from individual patients were collected at the time of surgery and at one additional sampling interval by aqueous tap, and analysed using a high-performance liquid chromatography assay. Results: Aqueous humour levels of levofloxacin continued to rise gradually, reaching a mean peak level (C(max)) of 4.4 mug/ml (+/- 2.5) at 60 mins after the last postoperative drop was administered. This level exceeded the minimum inhibitory concentration of common ocular pathogens at least fourfold. At 90 mins after the last drop, mean AH levels remained > 3 mug/ml. Conclusions: This is the first study to measure AH levels of levofloxacin after postoperative pulsed dosing in humans. Higher AH levels were found than in previously reported studies in which only preoperative drops were given and levels were measured at the time of surgery. Levels of levofloxacin continued to rise for 60 mins after administration of the last postoperative drop, demonstrating that delivery and maintenance of effective antibiotic levels may be achievable with alternative dosing schedules.
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12. |
- Sundelin, Karin
(författare)
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On posterior capsule opacification
- 2005
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- AimsPosterior capsule opacification (PCO) is the most common complication after cataractsurgery. The aim of this study was to increase our knowledge about PCO regardingquantification, treatment effects and how different designs of intraocular lenses(IOLs) influence occurrence.MethodsTo evaluate performed capsulotomy as a measurement of PCO a random sample ofcataract patients who had surgery in 1991 was studied 5 years after their surgery. Tofurther study quantification of PCO visual acuity, morphologic quantification of PCOand self-assessed visual function were compared in 21 patients with PCO. Effectsof treatment of PCO on functional outcome were investigated in 47 patients usingCatquest. In a retrospective study with a 3-year follow up, patients who had receivedan acrylic IOL during cataract surgery were compared with patients who had receivedpolymethylmethacrylate (PMMA) IOLs in terms of need for treatment of PCO. In aprospective clinical study with a 3-year follow up patients who had received siliconeIOLs with two different designs were compared. PCO was evaluated using Evaluationof Posterior Capsule Opacification (EPCO), a morphological method of quantification,and the number of performed capsulotomies was recorded.ResultsThe estimated incidence of PCO 5 years after cataract surgery was 43%, and the untreatedgroup with clinically significant PCO was approximately 9%. The incidence ofperformed capsulotomy was higher in women than in men. The morphological methodof quantifying PCO correlated with visual acuity and self-assessed visual function asmeasured with Catquest. Seventy-seven per cent of the PCO patients benefited fromcapsulotomy according to Catquest. The relative risk of needing capsulotomy was 3.6times higher in the PMMA group than in the acrylic group. Patients with the siliconeIOL with a sharp optic edge had significantly less PCO than patients with a roundedoptic edge IOL. Regression of PCO was noticed in some eyes.ConclusionIn a population without active follow up after cataract surgery, a group of untreatedpatients with PCO was found. They must be considered when using performed capsulotomyas an end-point for PCO. A commonly used method for quantification ofPCO (EPCO) is correlated with visual acuity and self-assessed visual function. Thevast majority of PCO patients benefited from treatment. IOL related factors, specifi-cally IOL design, are important in decreasing PCO occurrence.
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13. |
- Sundelin, Karin, et al.
(författare)
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Posterior capsule opacification: comparisons between morphology, visual acuity and self-assessed visual function.
- 2006
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Ingår i: Acta Ophthalmologica Scandinavica. - 1395-3907. ; 84, s. 667-673
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Tidskriftsartikel (refereegranskat)abstract
- ABSTRACT. Purpose: To investigate whether posterior capsule opacification (PCO) morphology, visual acuity (VA) and self-assessed visual function correlate, and to compare perceived visual disabilities with those of cataract patients with corresponding VA. Methods: Twenty-one patients with PCO were examined before capsulotomy. In adjunct to the ophthalmological examination, the patients completed a Catquest questionnaire and a digitized retroillumation image was acquired. The images were analysed with the Evaluation of Posterior Capsule Opacification (EPCO) program. Data for visual function were compared with data from the National Swedish Cataract Register (NCR). Results: The epco values were correlated with VA in the PCO eyes: the higher the epco score, the lower the VA. There were also correlations between the epco scores, satisfaction with vision, and perceived disabilities in daily life. Symptoms of glare were not significantly correlated with epco scores or with VA. Visual acuity in PCO eyes was better correlated with perceived disabilities and satisfaction with vision than VA in eyes with cataract. Conclusions: There was a significant correlation between epco scores and VA and between epco scores and Catquest. Consequently, the morphological method was related to the self-assessed visual function. Patients with PCO seemed to have more disturbed visual function, as defined by Catquest, than cataract patients with the same VA.
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14. |
- Sundelin, Karin, et al.
(författare)
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Self-assessed visual function for patients with posterior capsule opacification before and after capsulotomy.
- 2005
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Ingår i: Acta Ophthalmologica Scandinavica. - 1395-3907. ; 83, s. 729-733
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Tidskriftsartikel (refereegranskat)abstract
- ABSTRACT. Purpose: To describe the functional outcome, as defined using the Catquest questionnaire, for patients with posterior capsule opacification (PCO) after capsulotomy. Methods: A total of 47 patients with PCO were examined before and 1 month after capsulotomy. In addition to the ophthalmic examination, Catquest was completed and a digital image of the posterior lens capsule acquired. Results: Capsulotomy resulted in a good level of benefit, as defined using Catquest, for 77% of the patients. No subgroup of patients who derived an exceedingly good or poor level of benefit was identified. Disabilities in daily life, satisfaction with vision and symptoms of glare improved from treatment (p < 0.001, p < 0.001 and p = 0.002, respectively). The results were comparable with the benefits of cataract surgery. Conclusions: Self-assessed visual function as defined using Catquest improved after capsulotomy for the vast majority of patients with PCO. No group of patients with exceptionally good or poor levels of benefit could be identified with certainty. However, the majority of those with a poor outcome were elderly individuals with ocular comorbidity. The overall functional results from treatment of PCO were very similar to those achieved after cataract surgery.
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15. |
- Sundelin, Karin, et al.
(författare)
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Three-year folow-up of posterior capsule opacification with two different silicone intraocular lenses.
- 2005
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Ingår i: Acta Ophthalmologica Scandinavica. - 1395-3907. ; 83, s. 11-19
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Tidskriftsartikel (refereegranskat)abstract
- ABSTRACT. Purpose: To compare posterior capsule opacification (PCO) after cataract surgery with implantation of two silicone intraocular lenses (IOLs) with different designs. Methods: We carried out a prospective, clinical study of 116 patients randomized to standardized phacoemulsification with implantation of CeeOn Edge (n = 57) or SI40NB (n = 59) IOLs. The follow-up period was 3 years. To evaluate PCO morphologically, digital images were obtained and analysed using evaluation of posterior capsule opacification computer software (EPCO). The neodymium: YAG (Nd:YAG) capsulotomy rate was recorded. Results: At 2 and 3 years, the eyes with SI40NB IOLs had significantly more PCO than those with the CeeOn Edge IOLs (p = 0.00014 and p = 0.002). Nine Nd:YAG capsulotomies were performed in the SI40NB group and none in the CeeOn Edge group. This difference was statistically significant (p = 0.003). In some patients a regression of PCO was noticed and confirmed using EPCO. Statistically less PCO was noted when the capsulorhexis rim was placed so that it covered all 360 degrees of the optic of the IOL. Conclusions: A clinically and statistically significant difference in PCO development between CeeOn Edge and SI40NB IOLs at 2 and 3 years postoperatively was found. These findings support earlier studies indicating that a sharp edge of the optic is a more important factor in IOL design than IOL material in the prevention of PCO. Key words: posterior capsule opacification (PCO) – silicone – intraocular lens (IOL) – longterm follow-up – prospective – evaluation of posterior capsule opacification (EPCO) – capsulotomy – optic edge – regression
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16. |
- Åström, Charlotte, 1979-
(författare)
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Effects of vibration on muscles in the neck and upper limbs : with focus on occupational terrain vehicle drivers
- 2008
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Introduction: Occupational drivers of terrain vehicles are exposed to several risk factors associated with musculoskeletal symptoms in the lower back as well as in the neck and upper limbs. Vibration has been suggested to be a main risk factor. These drivers are exposed to both whole-body vibration (WBV) and hand-arm vibration (HAV). Aim: This study establishes the association between driving terrain vehicles and musculoskeletal disorders (MSDs) in the neck and upper limbs as well as hand-arm vibration syndrome (HAVS). In addition, this study examines the effect on muscles in the neck and upper limbs of the type of vibration exposure that occurs in occupational driving of terrain vehicles. Methods and results: In Paper I, a cross-sectional questionnaire study on occupational drivers of terrain vehicles, increased Prevalence Odds Ratios (POR) were found for numbness, sensation of cold and white fingers (POR 1.5-3.9) and for MSDs in the neck (POR 2.1-3.9), shoulder (POR 1.8-2.6) and wrist (POR 1.7-2.6). For the shoulders, neck and elbow, there appears to be a pattern of increased odds with increasing exposure time. In Paper II, an experimental study on the trapezius muscle, which included 20 men and 17 women, the mean frequency of the electromyography signal (EMGMNF) decreased significantly more in a three minute sub-maximal contraction without vibration (-3.71Hz and -4.37Hz) compared to with induced vibration (-3.54Hz and -1.48Hz). In Paper III, a higher initial increase of the mean of the root-mean-square of the electromyography signal (EMGRMS) was seen in a three minute sub-maximal contraction with vibration exposure compared to without vibration (0.096% vs. 0.045%). There was a larger mean EMGMNF decrease for NV compared to V in the total three minutes, and a larger decrease also in the first time period was seen for the NV compared to V. A small gender effect was also noticed. In Paper IV, the combination of HAV and WBV was studied in laboratory settings and resulted in a higher trapezius EMGRMS compared to the HAV and WBV separately. Conclusion: Occupational drivers of terrain vehicles are likely to experience symptoms related to HAVS and musculoskeletal symptoms in the neck and upper limbs. Local vibration does not seem to have any negative acute effects on trapezius muscle fatigue. Vibration exposure seems to cause an initial increase in muscle activity in the trapezius that could be related to recruitment on new motor-units. A combination of HAV and WBV causes a larger muscular demand on the trapezius muscle.
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