Biomedical subjects

J Sjöstrand

Publications and source records attributed to J Sjöstrand.

At least 19 recordsLinked to original sources

PubMed2005

Potential protective effects of NSAIDs/ASA in oxidatively stressed human lens epithelial cells and intact mouse lenses in culture.

PURPOSE: To study possible toxic effects of indomethacin, diclofenac, and celecoxib (NSAIDs) and acetylsalicylic acid (ASA) as well as potentially protective effects of these substances in oxidatively stressed human lens epithelial cells (HLEC) and in intact mouse lenses in culture. METHODS: HLEC and mouse lenses were incubated with NSAIDs or ASA alone or in the presence of H2O2. To study apoptosis the cells were then either stained with Hoechst 33342 or assayed for caspase-3 activity. Mouse lenses were studied with respect to lens transparency. RESULTS: Low concentrations of NSAIDs/ASA caused a significant protection against H2O2-induced apoptosis in HLEC whereas higher concentrations were toxic. CONCLUSION: The protective effects of NSAIDs/ASA against oxidative damage are confined to a relatively small therapeutic window.

Animals↗

PubMed2003

Evaluation of screening procedures for congenital cataracts.

AIM: To evaluate the efficacy of two different Swedish screening procedures for early detection of congenital cataracts in comparison with no screening. METHODS: Children born between January 1992 and December 1998 in Swedish regions with an established eye-screening routine procedure, diagnosed with congenital cataract, and operated on before 1 y of age, were included in a retrospective study. Age at referral and age at time of the operation were compared between regions using different screening procedures: screening in the maternity wards (Region 1), at the well-baby clinics (Region 2) and one region without any screening (Region 3). RESULTS: Seventy-two children were included in the study. Concerning early diagnosis and surgery, Region 1 differed significantly from Regions 2 and 3, which were more similar and were combined for further analysis. The difference in detected cases was greatest at 21 d of age (55% vs 18%; p < 0.001), but persisted even at 100 d of age (78% vs 64%; p < 0.02). Region 1 screening resulted in more and earlier cases detected than the other two regions (22 vs 15 per 100,000 births). In 72% of all cases, surgery was performed in response to referrals from either the maternity wards (36%), or the well-baby clinics (36%). However, half of the cases from the well-baby clinics were detected too late, i.e. at > 100 d. CONCLUSION: Eye screening in the maternity ward is preferable to well-baby clinic screening and to no screening at all, since it leads to early detection. Screening should also be performed routinely at well-baby clinics within the period when successful treatment is possible.

Cataract↗

PubMed2002

Long term visual outcome in amblyopia treatment.

AIM: To evaluate long term visual outcome of treatment for amblyopia. METHODS: In a previous study, 44 children with unilateral amblyopia caused by strabismus or anisometropia were enrolled in a prospective study investigating the results of treatment. All children were regularly examined up to at least 8 years of age and outcome was evaluated. All subjects were invited to a re-examination and in total 26 subjects attended. Two of these were excluded because of insufficient records. The final sample consists of 24 subjects. Mean follow up time was 10.4 (SD 1.9) years. RESULTS: For the amblyopic eyes, 17% deteriorated in visual acuity, 50% were stable, and 33% gained in visual acuity. For the non-amblyopic eyes, 8% lost one line in visual acuity, 38% were stable, and 54% gained in visual acuity. No eye in any subject shifted more than 0.2 logMAR units. The increase in visual acuity for the non-amblyopic eyes was significant, while the increase for the amblyopic eyes was not. All straight eyed anisometropic amblyopes showed a distinct decrease in magnitude of anisometropia. CONCLUSIONS: Visual acuity was essentially stable in the amblyopic eyes 10 years after cessation of treatment in the studied population.

Adolescent↗

PubMed2002

Changes in visual acuity from 4 to 12 years of age in children operated for bilateral congenital cataracts.

AIMS: To investigate the long term effects of age at surgery on the development of visual acuity (VA) by measuring VA from preschool age to puberty. Furthermore, to report the VA levels at 12 years of age in a geographically based cohort of operated congenital bilateral cataracts. METHODS: All children born in four western counties of Sweden between January 1980 and December 1993 who were diagnosed with congenital cataracts were included in a longitudinal prospective study. The monocular VA of the better eye in 38 subjects was analysed at 4, 7, 10, and 12 years of age, with 20 total and 18 partial cataracts. The mean follow up time was 9.3 years after surgery. RESULTS: The final value of VA was 0.4 or above for approximately 50% of the subjects at 12 years of age. Visual acuity improved to a considerable extent after school age, especially in children who underwent surgery between the ages of 7 weeks and 1 year. Results for partial cataracts were favourable compared to those for total cataracts, reaching a mean of approximately 0.5 at age 12. The mean VA in the group of total congenital cataracts operated on before 7 weeks of age achieved higher values of VA at 4 years of age compared to children with total cataracts operated on between 7 weeks and 1 year of age. However, no statistically significant difference in VA results among these groups could be proved. CONCLUSION: Visual acuity improves to a considerable extent after school age in children with delayed visual development caused by congenital cataracts. Surgery within 7 weeks results in a more rapid development of VA, initially.

Age Factors↗

PubMed2001

Resolution, separation of retinal ganglion cells, and cortical magnification in humans.

We present direct comparisons of resolution thresholds and quantitative estimates of retinal ganglion cell separation in humans with reported functional magnetic resonance imaging estimates of the human linear cortical magnification factor. Measurements of resolution thresholds (MAR), retinal ganglion cell (GC) densities, and linear cortical magnification factor (M) values were taken from the literature. Our objective was to analyse the apparent overrepresentation of human central vision in the visual cortex and to determine whether the cause of this is an effect of the uneven distribution of GC in the retina and/or that central GC have more devoted cortical area per cell. The reserved amount of cortical distance per retinal unit, i.e. the product of M on the one hand and effective GC separation, MAR, and GC receptive field separation on the other, indicates an overrepresentation of the fovea and immediately surrounding retina in the human striate cortex due to an increase in devoted cortical distance per central GC or resolution unit. This cannot be explained by lateral displacement of foveal ganglion cells nor by peripheral scaling, but rather by an additional magnification in the retino-cortical pathway.

Ganglia, Sensory↗

PubMed2001

Posterior capsule opacification with AcrySof and poly(methyl methacrylate) intraocular lenses. Comparative study with a 3-year follow-up.

PURPOSE: To evaluate whether reports of reduced posterior capsule opacification (PCO) rates with AcrySof intraocular lenses (IOLs) are applicable to a mixed group of cataract patients in everyday surgical practice. SETTING: Department of Ophthalmology, Kärnsjukhuset, Skövde, Sweden. METHODS: A retrospective study comparing a study group receiving an AcrySof IOL (n = 145) and a group receiving a poly(methyl methacrylate) (PMMA) IOL (n = 153) was performed. The follow-up was 3 years in both groups. The performance of a neodymium:YAG laser capsulotomy was used as the end point for clinically significant PCO. RESULTS: Nine capsulotomies (6.2%) were performed in the AcrySof group and 34 (22.2%) in the PMMA group. The difference in the capsulotomy rate between the 2 groups was highly significant (P <.001). The relative risk was 3.6 times higher in the PMMA group. CONCLUSIONS: There was a significant difference in the frequency of capsulotomy between AcrySof and PMMA IOLs in a mixed group of cataract patients in everyday clinical practice. This finding indicates the importance of the IOL type in PCO formation.

Acrylic Resins↗

PubMed2001

Visual acuity, residual amblyopia and ocular pathology in a screened population of 12-13-year-old children in Sweden.

PURPOSE: To establish the distribution of visual acuity and the prevalence of residual amblyopia and other ocular disorders in a vision-screened population group of 12-13-year-old children. METHODS: In total 1046 children were examined in a field study in Sweden. The examination included visual acuity, stereopsis, cover testing, red reflex, refractive retinoscopy and examination of the posterior pole. In selected cases VEP was also performed. RESULTS: Visual acuity > or =1.0 in at least one eye was present in 98% of cases. Residual amblyopia (< or =0.5) was found in 1.1% of the population. Manifest strabismus was found in 2.7%. There were only a small number of ocular opacities and posterior pole abnormalities. Ocular albinism was found in 7 cases. In 15 children the cause of subnormal VA was unexplained. CONCLUSION: Results for visual acuity, residual amblyopia and other ocular disorders are very similar to previous Nordic, vision-screened populations.

Adolescent↗

PubMed2001

Screening merits of the Lang II, Frisby, Randot, Titmus, and TNO stereo tests.

PURPOSE: Previous works show a pronounced disagreement on the reliability of stereo tests as screening tools for amblyopia and strabismus. This study's aim was to compare the ability of the Lang II, Frisby, Randot, Titmus, and TNO stereo tests to detect amblyopia and strabismus with visual acuity testing and cover testing. METHODS: A total of 1035 school children aged 12 to 13 years were examined in a field study in Monterrey, Mexico. In addition to the 5 stereo tests, the examination included visual acuity, cover testing, refraction (skiascopy), and inspection of the red reflex and posterior pole. RESULTS: Sensitivity ranged from 17% to 47% (Frisby-Titmus-Lang II-Randot-TNO, in order of occurrence). Of the 60 subjects with strabismus and/or amblyopia, only 8 subjects were identified by all 5 stereo tests. A considerable number of subjects (25), the majority of whom were amblyopic (23 subjects), were not identified by any of the tests. All stereo tests showed higher sensitivities for strabismus than for amblyopia. CONCLUSION: None of the 5 stereo tests studied is suitable for screening for amblyopia or strabismus. The results of both ocularly normal subjects and subjects with strabismus and/or amblyopia are variable, and there is no way of separating normal response from abnormal response.

Adolescent↗

PubMed2000

Glaucoma following congenital cataract surgery: an 18-year longitudinal follow-up.

PURPOSE: To report the occurrence of postoperative glaucoma and to evaluate risk factors. METHODS: Children born in four of the western counties of Sweden who were diagnosed with congenital cataracts formed a cohort (n=137). The following parameters were evaluated: age at cataract surgery; type of surgery; visual outcome; postoperative IOP; optic disc abnormalities; date of onset of the complication; number of reoperations, including treatment for secondary cataract; presence of systemic anomalies; microphthalmus; and eye-related anomalies. RESULTS: A diagnosis of glaucoma was recorded for 12% of the eyes. The mean follow-up time was 9.6 years. There is a relationship between surgery before the age of 10 days and development of glaucoma. Microphthalmus is an important risk factor as well. CONCLUSIONS: Despite modern surgical techniques the incidence of aphakic glaucoma is 10% or higher. No time-dependent increase in the incidence of late-onset glaucoma between the 1980s and the 1990s could be proven.

Age of Onset↗

PubMed2000

Myopisation: the refractive tendency in teenagers. Prevalence of myopia among young teenagers in Sweden.

PURPOSE: 1045 children between 12 and 13 years old were examined in a field study in the Göteborg area (Sweden). The aim of this study was to report the prevalence of refractive errors, with special attention to myopia, since there are no previous reports in Sweden about this age group. METHODS: The examination included visual acuity testing and refraction under cycloplegia. RESULTS: We found a prevalence of myopia (> or = -0.5D) of 49.7% and a prevalence of bilateral myopia of 39%. In the whole population, 23.3% were considered to need glasses (> or = -0.75D). We also found a prevalence of high myopia (> or = -5D) in 2.5% of the children. DISCUSSION: No statistically significant difference in myopia with respect to gender was found. The proportion of children needing glasses is considered the best indicator of the prevalence of myopia in this sample. The results confirm that this tendency towards myopisation in a teenage population in Göteborg is similar to the prevalence found in other parts of the world.

Adolescent↗

PubMed2000

Caspase and proteasome activity during staurosporin-induced apoptosis in lens epithelial cells.

PURPOSE: To determine what caspases are activated during staurosporin-induced apoptosis in cultured bovine lens epithelial cells (BLECs), to study the time course of caspase activation in relation to morphologic changes, and to investigate the effect of caspase and/or proteasome inhibition on apoptosis. METHODS: BLECs were incubated with staurosporin at different concentrations or for different times. Phosphatidylserine (PS) externalization was detected by annexin-V labeling, nuclear morphology was studied by staining with Hoechst 33342 stain (Hoechst, Frankfurt, Germany), and the percentage of apoptotic cells was determined by the TdT-dUTP terminal nick-end labeling (TUNEL) assay. The activity of caspase-1, -2, -3, -4, -8, and -9 as well as the chymotrypsin-like activity of the proteasome was measured by the use of fluorogenic peptide substrates. Inhibition of the proteasome was performed by incubation with 10 microM lactacystin, and caspases were inhibited by 1 microM Z-DEVD-FMK or 20 microM Z-VAD-FMK. RESULTS: Staurosporin treatment caused a dose- and time-dependent increase in the number of apoptotic cells and in caspase-3 activity. Activation of caspase-2, -4, -8, and -9 was also seen. Caspase activity was increased after 3 hours' incubation with 1 microM staurosporin, which is also the time when most cells became annexin-V-positive. Nuclear changes indicative of apoptosis, viewed with both Hoechst and TUNEL staining, appeared after 4 to 6 hours of staurosporin incubation. Incubation of BLECs with lactacystin caused reduction of proteasome activity and increased apoptosis, evidenced in both the TUNEL assay and caspase-3 activation. Preincubation of lens epithelial cells with caspase inhibitors caused complete inhibition of lactacystin- or staurosporin-induced caspase-3 activation (Z-DEVD-FMK/Z-VAD-FMK) and also of caspase-2, -4, -8, and -9 (Z-VAD-FMK), but the reduction in TUNEL-positive cells was only partial. PS translocation and DNA fragmentation after staurosporin treatment occurred despite complete caspase blockade. CONCLUSIONS: Staurosporin-induced apoptosis in BLECs involves activation of several caspases. Inhibition of the proteasome causes caspase-3 activation and apoptosis. Both staurosporin- and lactacystin-induced apoptosis can be executed in a caspase-independent manner. The present data are useful for understanding of proteolytic mechanisms during apoptosis in lens epithelial cells, which may be an important event in normal lens development as well as in some types of cataract.

Acetylcysteine↗

PubMed1999

Differential inhibition of three peptidase activities of the proteasome in human lens epithelium by heat and oxidation.

The proteasome is a large protease complex that is thought to be responsible for proteolytic removal of damaged proteins. We have previously shown that the level of proteolytic activity due to the proteasome is lower in lens epithelium from human cataractous lenses compared to the activity in epithelium from clear donor lenses. This study aimed to characterize the three main peptidase activities of the proteasome in human lens epithelium with respect to kinetic properties and sensitivity to heat and oxidation. Human lens epithelia were obtained from cataract surgery and analysis performed on pools of epithelial cell cytoplasm. Using the fluorogenic peptide substrates Suc-Leu-Leu-Val-Tyr-AMC (LLVY), Boc-Val-Gly-Arg-AMC (VGR) and Z-Leu-Leu-Glu-betaNA (LLE), Km-values of 56, 678 and 108 micrometers were obtained. All peptidase activities were inhibited by lactacystin, a specific proteasome inhibitor, but at very different rates; with LLVY-hydrolysing activity being the most sensitive (Ki50%=0.15 micrometers). Thermostability was investigated by performing the proteolytic assay at 20 degrees, 37 degrees and 53 degrees C. The trypsin-like activity, as measured by VGR, was completely stable at 53 degrees C for at least 24 hr whereas hydrolysis of LLVY and LLE declined after a few hours at 37 degrees C. Oxidative inhibition was induced by incubation of the samples in 0.5 m m H2O2for 1 or 24 hr. One hour exposure to H2O2caused moderate inhibition of all peptidase activities. The activity could be partially restored by adding 1 m m dithiotreitol, indicating the dependency on intact SH-groups. After 24 hr, peptidase activities were decreased to 25% (LLVY), 73% (VGR) and 44% (LLE) of corresponding control. This inhibition was irreversible for VGR and LLE, but could be partly prevented by the presence of heat shock protein 90 (LLVY and VGR) or alpha-crystallin (LLVY). These data show that the peptidase activities of the human lens proteasome can be modulated by metabolites, such as reactive oxygen species, and by endogenous proteins such as alpha-crystallin and heat shock protein 90.

Acetylcysteine↗

PubMed1999

Morphometric study of the displacement of retinal ganglion cells subserving cones within the human fovea.

BACKGROUND: A study was carried out to measure the displacement of retinal ganglion cells subserving the cones within the human fovea. METHODS: Four human retinas were examined along the nasal or vertical hemi-meridians. Total displacement was estimated by adding the displacement due to fibres of Henle and bipolar cells, measured as the lateral extension of the Henle fibres and of the obliquely running fibre bundles within the inner nuclear layer, respectively. RESULTS: At the foveal border (0.5-0.8 mm or 1.8-2.9 deg eccentricity) the mean offset due to fibres of Henle and mean total lateral displacement was at a maximum of 0.32 +/- 0.03 mm and 0.37 +/- 0.03 mm, respectively. A steep decrease of displacement was found outside the foveal border out to an eccentricity of 2.0-2.5 mm. We were able to plot displacement along the vertical meridian in relation to eccentricity with good correlation between three eyes. The data were used to establish different mathematical functions describing the relation between eccentricity and displacement. These functions were applied to previously presented data on densities of retinal ganglion cells and cones. CONCLUSIONS: The present estimates of displacement within the human central fovea offer the possibility of analysis of quantitative relations between cones and retinal ganglion cells. Our data provide predictive guidance by establishing that vitreo-retinal procedures causing damage to retinal ganglion cells up to 1 mm from the foveal centre could have implications for loss of information generated within the fovea.

Adult↗

PubMed1999

Quantitative estimations of foveal and extra-foveal retinal circuitry in humans.

For an understanding of the basis for psychophysical measurement of visual resolution, quantitative morphological studies of retinal neuronal architecture are needed. Here we report on cell densities and retinal ganglion cell:cone ratio (RGC:C) from the foveal border to the peripheral retina (34 degrees eccentricity). Quantitative estimates of RGC and C densities were made using a modified disector method in three vertically sectioned human retinae and were adjusted for RGC displacement. In agreement with our previous data on humans, we found an RGC:C ratio close to 3 at 2-3 degrees eccentricity. Outside the foveal border, the ratio declined to 1.0 at 7.5 degrees eccentricity and to 0.5 at eccentricities larger than 19 degrees. Center-to-center separation of C and RGC in addition to center-to-center separation of estimated 'receptive fields' was calculated at corresponding locations along the superior and inferior hemimeridians. The center-to-center separation of estimated 'receptive fields' was found to be more closely related to resolution thresholds from the fovea to 19 degrees eccentricity than was the separation of RGC and C. On the basis of these quantitative estimates, models for neural circuitry involved in central and peripheral spatial vision can be discussed.

Cell Count↗

PubMed1999

Posterior capsule opacification 5 years after extracapsular cataract extraction.

PURPOSE: To find out whether there is a "hidden" group of patients with posterior capsule opacification (PCO) 5 years after cataract surgery and to establish the incidence of PCO. SETTING: Department of Ophthalmology, Sahlgrenska University Hospital, Gothenburg, Sweden. METHODS: A random sample (n = 164) was selected among patients who had extracapsular cataract extraction (ECCE) with intraocular lens implantation in 1991 (N = 1672). All surgically treated cases that required neodymium:YAG (Nd:YAG) laser capsulotomy (n = 37) within the first 5 years after surgery were recorded. Patients still alive 5 years after surgery who had not had Nd:YAG treatment were offered an eye examination to determine whether PCO requiring capsulotomy existed. RESULTS: Thirty-seven of 110 patients (34%) alive 5 years after surgery had an Nd:YAG capsulotomy during the first 5 postoperative years. Follow-up was possible in 51 of 73 untreated patients (70%). Clinically significant PCO according to specified criteria was found in 7 cases (14%). Half of them would benefit from treatment; the other half had visual impairment from other eye disease. CONCLUSIONS: The estimated incidence of PCO 5 years after ECCE was 43%. Five years after surgery, there was an untreated group with clinically significant PCO, approximately 9% of the surgically treated population. This hidden group must be considered in PCO studies.

Aged↗

PubMed1999

Longitudinal changes in visual acuity and visual ability in a cohort followed from the age of 70 to 88 years.

PURPOSE: To assess the change in visual acuity (VA) for distance and near and to correlate VA to changes in visual ability in a longitudinal study group followed from 70 to 88 years. METHODS: In the population-based study H70 in Gothenburg, Sweden, 958 subjects from the original cohort were eye examined at age 70 and the surviving subjects were reexamined at age 82 (n=203) and at 88 years (n=129). Evaluation of change in visual function between age 82 and 88 was made in 66 subjects who took part in all three eye examinations. RESULTS: The VA in the subsample (n=66) showed minimal difference compared to the cross-sectional groups. At age 70 nearly 100% of both sexes had VA> or =0.8. At age 82 about 50% and at age 88 about 25% had this VA level. Males retained a slightly better visual acuity compared to women. VA< or =0.3 was found in about 10% at age 82 and in >20% at age 88. Reading ability remained high, but at 82 years 1.6% and at 88 years 10.5% could benefit from adjustment of their near glasses. Visual ability corresponded well to VA at age 82, but not at 88 years. Women lost the ability for most tasks, whereas men showed small changes. CONCLUSIONS: The majority of old people had good distance and near vision. A deterioration in visual acuity did not necessarily mean a negative change in visual ability. This emphasizes the importance of relating objective and subjective findings regarding VA and visual impairment to functional ability of the oldest of the elderly.

Activities of Daily Living↗

PubMed1999

The occurrence of congenital cataract in western Sweden.

PURPOSE: To estimate the occurrence of congenital cataract in a Nordic country. METHODS: In 1980, we constructed a database in the Department of Ophthalmology, Göteborg University, containing basic data from all cases in western Sweden diagnosed with congenital cataract. By collecting and processing these data from 1980 onwards, we hoped to improve the management of congenital cataract treatment and to optimize the outcome of the treatment. RESULTS: In this study, the incidence of congenital cataract in the four western counties of Sweden was evaluated. The occurrence rate of all cases with congenital cataract during the study period was 36 cases per 100,000. The occurrence rate for dense bilateral and all unilateral cases were both 14 per 10,0000 each. CONCLUSION: There were no time-related changes in incidence of congenital cataract from 1980 until today, although there was a large variation in the yearly incidence.

Cataract↗

PubMed1999

Inheritance of strabismus and the gain of using heredity to determine populations at risk of developing strabismus.

PURPOSE: In the Nordic countries 2 to 4% of the population squint or have been squinting. Since strabismus is one of the major causes of amblyopia early detection and treatment is important for preventing this development. For centuries it has been recognized that strabismus is hereditary. Identifying individuals with a family history of squinting could give access to a risk population for a selective screening. METHODS AND RESULTS: 1,571 children were selected for this study. All children that took part in a voluntary eye examination at one year of age (born 1978-1983) in the city of Vasteras, Sweden and that had a family history of strabismus were selected together with controls. The study was a 6-year follow-up from 1 to 7 years of age. Parental knowledge of squint among relatives and measured high hyperopia (>3.0 D) present at 1 year of age were each and in combination evaluated as a risk indicator for development of strabismus between 1 to 7 years of age. CONCLUSION: The study indicates that a family history of squint in combination with measured high hyperopia can be used in a selective screening to identify a population with an increased risk of 4 to 6 times for developing strabismus. Among the children with parental knowledge of squint among several relatives of both the parents, those with high hyperopia developed strabismus in almost every second case while this was the case in only approximately 10% of those with low hyperopia. Finally, heredity is an important risk indicator that can be used for selective screening purpose. Its potential as a risk indicator is substantially increased when combined with a high hyperopia.

Child↗