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1.
Occup Med (Lond) ; 72(5): 289-297, 2022 07 11.
Article in English | MEDLINE | ID: mdl-35512455

ABSTRACT

BACKGROUND: The occupational well-being (OW) of educators can be defined as a balance between resources and workload factors as seen from four aspects of working life: (i) individual, (ii) working conditions, (iii) professional competence and (iv) work community. The research in this study examined the individual aspect as particular importance to the physical and mental workability of educators. AIMS: To study the individual aspect of the OW of educators as well as the associating factors. METHODS: A cross-sectional survey design was conducted among educators working in health and social care education in Finland. The data were collected with an electronic survey using the 'Occupational well-being of social and health care teachers-index questionnaire'. The data were analysed with an SPSS version 27 using descriptive statistics, explorative factor analysis and linear regression analysis. RESULTS: The educators (n = 552, response rate 31%) assessed their resources for managing their mental workload as quite poor (2.41, standard deviation [SD] 0.98). In addition, workplace support promoting OW was assessed as being quite poor (2.37, SD 0.88), and as especially requiring more measures during working hours. Associations with the individual aspect of OW were found between the personal and work-related background variables as well as overall OW. CONCLUSIONS: The perceptions of the educators indicated that resources to cope with workload factors should be promoted. Investing in educators' resources at work, enabling well-being actions during working hours and avoiding backlog situations would all help promote the educators' OW.


Subject(s)
Social Support , Workload , Cross-Sectional Studies , Educational Status , Humans , Surveys and Questionnaires
2.
J Biomed Mater Res A ; 83(2): 407-13, 2007 Nov.
Article in English | MEDLINE | ID: mdl-17450585

ABSTRACT

Synthetic biodegradable polymers have many potential therapeutic applications. In ophthalmology, biodegradable polymers have been used as viscoelastic agents and surgical implants. Other potential applications include controlled release of drugs and growth factors, gene therapy, and tissue engineering. In the present study, in vitro biocompatibility of three biodegradable polymers, 50:50 PDLGA, 85:15 PDLGA, and Inion GTR membrane was evaluated in comparison to tissue culture polystyrene by investigating cell proliferation and potential acute toxicity by the WST-1 cytotoxicity/cell proliferation test, the ATP test, and the lactate dehydrogenase (LDH) test. Evaluations were conducted with cell line cultures from various ocular tissues, human corneal epithelial cells (HCE), rabbit stromal fibroblasts (SIRC), bovine corneal endothelial cells (BCE), human conjunctival epithelial cells (IOBA-NHC), and human retinal pigment epithelial cells (ARPE-19) by direct contact studies by plating the cells on the polymer film specimens in 96-wells. The proliferation results show that cell lines from various ocular tissues attached and grew on PDLGA 50:50, PDLGA 85:15, and Inion GTR membrane. Cytotoxicity experiments with the LDH and ATP tests showed no or extremely slight toxic adverse effects. These polymers have potential to be used as scaffolds in cell transplantation devices or as surgical implants.


Subject(s)
Biocompatible Materials/metabolism , Biopolymers/metabolism , Epithelium, Corneal/metabolism , Adenosine Triphosphate/metabolism , Animals , Cattle , Cell Adhesion , Cell Line , Epithelial Cells/cytology , Epithelial Cells/metabolism , Epithelium, Corneal/cytology , Humans , Polystyrenes/metabolism , Rabbits
3.
Acta Ophthalmol Scand ; 81(5): 495-9, 2003 Oct.
Article in English | MEDLINE | ID: mdl-14510798

ABSTRACT

PURPOSE: 3Tamoxifen and toremifene are non-steroidal anti-oestrogens widely used in the treatment of advanced breast cancer and as adjuvant therapy following surgery in early stage disease. Tamoxifene has also been approved for use in reducing the incidence of breast cancer amongst high risk women. However, certain well documented adverse effects, mainly involving the reproductive organs, have been reported amongst users of both drugs. The aim of this study was to monitor the ocular side-effects of both of these commonly used anti-oestrogens. METHODS: Sixty postmenopausal (age range 50-79 years) breast cancer patients were randomized into adjuvant tamoxifen or toremifene therapy groups for 3 years. Prior to commencement of medication, a thorough ocular examination was undertaken. The first follow-up visit took place after 6 months and the remaining three at 12-month intervals thereafter. RESULTS: Sixteen patients had cataract at the first visit (seven in the tamoxifen group and nine in the toremifene group). Ten patients developed cataract during the study period (five in each group), giving annual cataract rates of 6.8% and 6.2% in the tamoxifen and toremifene groups, respectively. Three patients had macular crystals at the first visit (one in the tamoxifen group and two in the toremifene group). The crystals remained stable throughout the follow-up. Macular drusen were diagnosed in five patients at the first ophthalmological check-up (two in the tamoxifen and three in the toremifene group). Two patients in the toremifene group developed drusen maculopathy during follow-up visits. Yellowish spots in the macular area were found in one tamoxifen-treated patient at the second visit. At the final visit after 3.5 years' follow-up the spots had disappeared. No abnormal corneal findings or keratopathy were documented during the follow-up. CONCLUSION: We observed no serious ocular side-effects among the 60 breast cancer patients treated with tamoxifen or toremifene over a 3.5-year period.


Subject(s)
Breast Neoplasms/drug therapy , Estrogen Antagonists/adverse effects , Eye/drug effects , Tamoxifen/adverse effects , Toremifene/adverse effects , Aged , Female , Follow-Up Studies , Humans , Incidence , Macula Lutea , Middle Aged , Retinal Diseases/epidemiology
4.
Phys Rev Lett ; 89(18): 185503, 2002 Oct 28.
Article in English | MEDLINE | ID: mdl-12398615

ABSTRACT

We report tensile failure experiments on paper sheets. The acoustic emission energy and the waiting times between acoustic events follow power-law distributions. This remains true while the strain rate is varied by more than 2 orders of magnitude. The energy statistics has the exponent beta approximately 1.25+/-0.10 and the waiting times the exponent tau approximately 1.0+/-0.1, in particular, for the energy roughly independent of the strain rate. These results do not compare well with fracture models, for (brittle) disordered media, which as such exhibit criticality. One reason may be residual stresses, neglected in most theories.

5.
Toxicol In Vitro ; 16(2): 193-200, 2002 Apr.
Article in English | MEDLINE | ID: mdl-11869882

ABSTRACT

The cytotoxicity of the selected systemic and intravitreally dosed drugs tamoxifen, toremifene, chloroquine, 5-fluorouracil, gentamicin and ganciclovir was studied in retinal pigment epithelium (RPE) in vitro. The cytotoxicity was assayed in the human RPE cell line D407 and the pig RPE cell culture using the WST-1 test, which is an assay of cell proliferation and viability. The effects of experimental conditions on the WST-1 test (cell density, serum content in the culture medium, the exposure time) were evaluated. The EC50 values in tamoxifen-treated D407 cells ranged between 6.7 and 8.9 micromol/l, and in pig RPE cells between 10.1 and 12.2 micromol/l, depending on the cell density used. The corresponding values for toremifene were 7.4 to 11.1 micromol/l in D407 cells and 10.0 to 11.6 micromol/l in pig RPE cells. In chloroquine-treated cells, the EC50 values were 110.0 micromol/l for D407 cells and 58.4 micromol/l for pig RPE cells. Gentamicin and ganciclovir did not show any toxicity in micromolar concentrations. The exposure time was a significant factor, especially when the drug did not induce cell death, but was antiproliferative (5-fluorouracil). Serum protected the cells from the toxic effects of the drugs. Both cell cultures were most sensitive to tamoxifen and toremifene, and next to chloroquine. The drug toxicities obtained in the present study were quite similar in both cell types; that is, the pig RPE cells and the human D 407 cell line, despite the differences in, for example, the growth rate and melanin contents of the cell types. Owing to the homeostatic functions important for the whole neuroretina, RPE is an interesting in vitro model for the evaluation of retinal toxicity, but, in addition to the WST-1 test, more specific tests and markers based on the homeostatic functions of the RPE are needed.


Subject(s)
Drug-Related Side Effects and Adverse Reactions , Pigment Epithelium of Eye/drug effects , Animals , Cell Division/drug effects , Cell Survival/drug effects , Cells, Cultured , Chloroquine/adverse effects , Dose-Response Relationship, Drug , Fluorouracil/adverse effects , Ganciclovir/adverse effects , Gentamicins/adverse effects , Humans , Pigment Epithelium of Eye/pathology , Species Specificity , Swine , Tamoxifen/adverse effects , Toremifene/adverse effects
6.
Pharmacol Toxicol ; 88(1): 27-33, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11169158

ABSTRACT

The effects of tamoxifen, toremifene and chloroquine on the phagocytosis of rod outer segments by retinal pigment epithelium were evaluated in human retinal pigment epithelial cell line D407 and pig retinal pigment epithelial cell culture. Retinal pigment epithelial cells were exposed to different concentrations of tamoxifen (1-20 microM), toremifene (1-20 microM) and chloroquine (1-1000 microM), and challenged with FITC-labeled rod outer segments for 24 hr. The phagocytized (bound and ingested) rod outer segments were measured fluorometrically, and the effect of the drugs on the phagocytosis was determined. The cytotoxicity of the drugs was evaluated by measuring their effects on mitochondrial enzyme activities (WST-1-test). The results showed that the test compounds inhibited the phagocytosis of rod outer segments in both D407 and pig retinal pigment epithelial cells. The phagocytic activity was more sensitive to tamoxifen (EC(50) 7.2 microM for D407 cells and 3.6 microM for pig retinal pigment epithelial cells) and toremifene (EC(50) 6.2 microM and 3.1 microM respectively) than to chloroquine (EC(50) 77.2 microM for D407 cells). The inhibition of rod outer segment phagocytosis in both cell cultures started at lower dose levels of test compounds than the cytotoxicity indicated by the WST-1-test. The experiments were carried out both in serum-free medium and serum-containing medium. Serum seemed to be a critical factor in the medium and caused difficulties in the interpretation of the results.


Subject(s)
Chloroquine/pharmacology , Phagocytosis/drug effects , Pigment Epithelium of Eye/drug effects , Rod Cell Outer Segment/physiology , Tamoxifen/pharmacology , Toremifene/pharmacology , Animals , Cell Division/drug effects , Cell Line , Cell Survival/drug effects , Culture Media, Serum-Free , Dose-Response Relationship, Drug , Humans , Mitochondria/drug effects , Mitochondria/enzymology , Phagocytosis/physiology , Pigment Epithelium of Eye/physiology , Rod Cell Outer Segment/drug effects , Swine
9.
J Telemed Telecare ; 5(2): 118-21, 1999.
Article in English | MEDLINE | ID: mdl-10628022

ABSTRACT

We carried out a study of the value of videoconferencing in consultations between general practitioners (GPs) and ophthalmologists in Finland. We used ISDN lines (128 kbit/s) between the Primary Health Care Centre in Ikaalinen and the ophthalmology clinic at the Tampere University Hospital (TAUH). Questionnaires covering both clinical and technical matters were given to patients and doctors after the consultation. During the 10-month study, consultations were carried out successfully for 23 of 24 patients (96%). Most consultations (84%) took less than 15 min. If we had not had this system, the GP would have made 21 referrals to an ophthalmologist. After teleconsultation, six patients were sent to the TAUH, so the system saved 15 referrals. Twenty-two patients (92%) thought that videoconferencing was a reliable tool for GPs. Our system proved to be a valuable and reliable tool for the GPs in ophthalmology consultations and continuing education.


Subject(s)
Family Practice , Ophthalmology , Remote Consultation , Evaluation Studies as Topic , Finland , Humans
10.
Altern Lab Anim ; 27(3): 417-24, 1999.
Article in English | MEDLINE | ID: mdl-25470681

ABSTRACT

This article reviews in vitro testing of retinal toxicity in retinal pigment epithelium (RPE) cell cultures. It is based on the literature on RPE cell cultures and on our recent studies on the retinal toxicity of selected amphiphilic drugs. The RPE plays a major role in maintaining the homeostasis and health of the retina. Various pharmacological agents are known to cause adverse effects in RPE cells. For example, long-term treatment with chloroquine in patients with rheumatoid arthritis has induced retinopathy, and tamoxifen, a drug that is commonly used in the treatment of advanced breast cancer and in the prevention of breast cancer among high-risk women, has been reported to cause retinal changes and impaired vision. During our research, we have developed novel in vitro methods for evaluating the retinal toxicity of xenobiotics. We have used a pig RPE primary culture and a human RPE cell line (D407), which retain epithelial cell characteristics. They form a layer of hexagonal cells with intercellular junctions, and possess a keratin-containing cytoskeleton. They are both good models for determining the retinal cell toxicity of test compounds. Further studies on phagocytic activity, lysosomal enzyme activity and glutamate uptake might generate new methods for the toxicological evaluation of the retinal side-effects of drugs in vitro.

11.
Pharmacol Toxicol ; 83(6): 246-51, 1998 Dec.
Article in English | MEDLINE | ID: mdl-9868742

ABSTRACT

Retinal pigment epithelial cells carry out phagocytosis and digestion of material shed from the photoreceptor outer segments. In this process, the integrity of lysosomal enzymes is of major importance. In the present study the effects of tamoxifen, toremifene and chloroquine on the activity of two lysosomal enzymes (cathepsin D and N-acetyl-beta-D-glucosaminidase) in the retinal pigment epithelial cells were studied. Retinal pigment epithelial cells from pig eyes were cultured for two weeks in Dulbecco's Modified Eagle Medium, after which the cells were exposed to 1-40 microM concentrations of tamoxifen citrate, toremifene citrate and chloroquine diphosphate. To eliminate possible medium-borne oestrogenic mechanisms, the test was repeated using phenol red-free medium with charcoal-stripped fetal calf serum. The exposure time was one week, after which the lysosomal enzymes cathepsin D and N-acetyl-beta-glucosaminidase were determined. Cellular injuries were assessed by quantifying the leakage of lactate dehydrogenase into the culture medium. Cathepsin D and N-acetyl-beta-D-glucosaminidase showed different sensitivities to tamoxifen, toremifene and chloroquine. The main lysosomal protease cathepsin D was more sensitive than N-acetyl-beta-D-glucosaminidase to the effects of tamoxifen and toremifene, possibly due to their antioestrogenic properties. The phenol red-free medium with charcoal-stripped serum seemed to make the drugs more effective than the reference medium. Chloroquine had only a minor effect on the lysosomal protease cathepsin D, but a clearer effect could be seen on N-acetyl-beta-glucosaminidase.


Subject(s)
Antimalarials/pharmacology , Chloroquine/pharmacology , Estrogen Antagonists/pharmacology , Pigment Epithelium of Eye/drug effects , Tamoxifen/pharmacology , Toremifene/pharmacology , Acetylglucosaminidase/drug effects , Animals , Cathepsin D/drug effects , Cells, Cultured , Pigment Epithelium of Eye/enzymology , Swine
12.
Pharmacol Toxicol ; 82(1): 19-22, 1998 Jan.
Article in English | MEDLINE | ID: mdl-9527641

ABSTRACT

Ocular and systemic absorption and antagonist activity of topical 1% cyclopentolate were studied in 11 elderly patients undergoing extracapsular cataract extraction, and in 8 healthy female volunteers. The patients received two 35 microl drops of cyclopentolate unilaterally and the healthy volunteers one 30 microl drop bilaterally to the lower conjunctival cul-de-sac of the eye. The drug concentrations were measured with radioreceptor assay and receptor occupancies with radiooccupancy assay using isolated rat brain muscarinic cholinoceptors. In the patient group, cyclopentolate concentrations in aqueous humour were approximately 3000 times higher than those in plasma. Muscarinic cholinoceptors were occupied totally (more than 99.9%) by aqueous humour and 3-18% by plasma taken at 55-125 min. after the drug application. In healthy volunteers peak plasma concentration of cyclopentolate, 2.06+/-0.86 (mean+/-S.D.) nM, occurred at 53 min., maximum receptor occupancy being 5.9+/-2.1%. The maximum pupillary dilatation occured at 30 min. after the drug application. At the same time the near point of vision was extended to more than 50 cm in all subjects. After topical application plasma receptor occupancy was not high enough to cause any significant changes in heart rate and in PQ time. None of the subjects experienced subjectively or objectively adverse effects to be attributed to cyclopentolate.


Subject(s)
Cataract/metabolism , Cyclopentolate/pharmacokinetics , Muscarinic Antagonists/pharmacokinetics , Absorption , Administration, Topical , Aged , Animals , Cyclopentolate/blood , Female , Humans , Male , Muscarinic Antagonists/blood , Ophthalmic Solutions/administration & dosage , Rats , Receptors, Muscarinic/metabolism
15.
J Ocul Pharmacol Ther ; 11(1): 37-40, 1995.
Article in English | MEDLINE | ID: mdl-8535955

ABSTRACT

Dipivefrin hydrochloride is a lipophilic prodrug for epinephrine hydrochloride, allowing lower concentration of the drug to achieve the same intraocular pressure lowering effect and having also less harmful effects than epinephrine hydrochloride. However, harmful effects have been associated also with the use of dipivefrin and here we report of a case of corneal vascularization during long-term use of dipivefrin.


Subject(s)
Corneal Neovascularization/chemically induced , Corneal Opacity/chemically induced , Epinephrine/analogs & derivatives , Blepharitis/chemically induced , Blepharitis/pathology , Conjunctival Diseases/chemically induced , Conjunctival Diseases/pathology , Corneal Neovascularization/pathology , Corneal Opacity/pathology , Epinephrine/adverse effects , Epinephrine/therapeutic use , Female , Glaucoma, Open-Angle/drug therapy , Humans , Hyperemia/chemically induced , Hyperemia/pathology , Middle Aged
16.
J Ocul Pharmacol Ther ; 11(3): 349-59, 1995.
Article in English | MEDLINE | ID: mdl-8590267

ABSTRACT

A retrospective study of 26 cases of postoperative endophthalmitis occurring after extracapsular cataract extraction and lens implantation was conducted between January 1989 and December 1992. Twenty-one of the 26 cases (81%) were diagnosed within two weeks after surgery. The most common organism isolated was Staphylococcus saprophyticus (23%). After the bacterial samples had been taken, cefotaxime or gentamicin was injected into anterior chamber and vitreous space. The therapy regimen consisted of topical tobramycin, Polysporin (polymyxinsulfate, neomycinsulfate and gramicidin), dexamethasone and atropine and parabulbar cefotaxime, netilmicin and betamethasone. Cefotaxime or, alternatively, clindamycin, ciprofloxacin and prednisolone were given systemically. The final visual acuity of 20/40 or more was obtained in 15 cases (58%). Twenty-one patients (81%) achieved a visual acuity of 20/400 or better. Three patients had no light perception after the treatment of endophthalmitis. Silk as suture material in wound closure and rupture of the posterior capsule were found to be risk factors in the development of endophthalmitis. The results of the present study show that effective drug treatment also results in good visual outcome.


Subject(s)
Cataract Extraction/adverse effects , Endophthalmitis/drug therapy , Eye Infections, Bacterial/drug therapy , Postoperative Complications/drug therapy , Adult , Aged , Aged, 80 and over , Anterior Chamber/drug effects , Anterior Chamber/microbiology , Anti-Bacterial Agents , Anti-Inflammatory Agents/therapeutic use , Bacteria/isolation & purification , Drug Therapy, Combination/therapeutic use , Endophthalmitis/microbiology , Eye Infections, Bacterial/microbiology , Female , Humans , Injections , Lenses, Intraocular , Male , Middle Aged , Postoperative Complications/microbiology , Retrospective Studies , Risk Factors , Steroids , Visual Acuity , Vitreous Body/drug effects , Vitreous Body/microbiology
17.
Ophthalmic Res ; 27 Suppl 1: 150-3, 1995.
Article in English | MEDLINE | ID: mdl-8577454

ABSTRACT

The retinal pigment epithelium (RPE) removes the outer segments of photoreceptor cells by phagocytosis. We studied the effects of tamoxifen and chloroquine on the activity of the lysosomal enzymes N-acetyl-beta-glucosaminidase and cathepsin D in RPE in vitro to evaluate the possible eye toxicity caused by these drugs. The results show decreases in the activities of lysosomal enzymes after drug exposure. The enzymes tested seemed to be more sensitive to tamoxifen than to chloroquine. A profound decrease in the activities of the lysosomal enzymes only started at concentrations above therapeutic dose levels.


Subject(s)
Antimalarials/toxicity , Chloroquine/toxicity , Estrogen Antagonists/toxicity , Pigment Epithelium of Eye/drug effects , Tamoxifen/toxicity , Acetylglucosaminidase/metabolism , Animals , Cathepsin D/metabolism , Cells, Cultured , Drug Evaluation , L-Lactate Dehydrogenase/metabolism , Lysosomes/enzymology , Pigment Epithelium of Eye/enzymology , Swine
18.
Br J Clin Pharmacol ; 35(5): 479-83, 1993 May.
Article in English | MEDLINE | ID: mdl-8512760

ABSTRACT

1. Eight volunteers received in randomized order two 30 microliters drops of either 1% w/v cyclopentolate hydrochloride or a corresponding amount of cyclopentolate polygalacturonate in saline or in acetate buffer in one eye. Cyclopentolate concentrations in plasma were measured by a radioreceptor assay. 2. Peak plasma drug concentrations of about 3 ng ml-1 occurred within 30 min after all formulations. Occasionally, a second concentration peak in plasma, probably reflecting drug absorption from the gastrointestinal tract, was seen after 2 h. The mean elimination half-life of cyclopentolate was 111 min when all subjects and formulations were considered together. There were no statistically significant differences between the formulations with respect to the time-course of plasma drug concentration. 3. The maximal mydriatic effect was reached within about 15 min and was maintained for several hours, often being 1/3 of its peak value after 30 h. Similarly, an intense cycloplegic response was achieved within a few minutes, the peak changes in the near-point of vision being 9 to 10 dioptres. The cycloplegic response was more intense after one of the polygalacturonate complexes, especially at later time points.


Subject(s)
Cyclopentolate/pharmacokinetics , Eye/drug effects , Adult , Buffers , Cyclopentolate/administration & dosage , Excipients , Female , Half-Life , Humans , Hydrogen-Ion Concentration , Male , Ophthalmic Solutions , Pectins , Pupil/drug effects
19.
Surv Ophthalmol ; 37(6): 435-56, 1993.
Article in English | MEDLINE | ID: mdl-8100087

ABSTRACT

Due to absorption several ocularly applied medications give rise to systemic side-effects. The problem of systemic drug absorption should be taken into account in designing ocular drug and dosage forms so that oculospecificity of the medications is optimized. In this review we summarize the current knowledge about the systemic absorption of ocularly applied topical drugs. Special emphasis is directed to the methods that can be used to minimize systemic absorption and increase the oculospecificity of drugs, e.g., reducing volume and increasing viscosity of eyedrops, controlling drug release from depot preparations, prodrug-derivatization, and addition of vasoconstrictive agents.


Subject(s)
Ophthalmic Solutions/pharmacokinetics , Absorption , Administration, Topical , Adrenergic beta-Antagonists/pharmacokinetics , Animals , Biological Availability , Blood/metabolism , Cell Membrane Permeability , Drug Delivery Systems , Eye/metabolism , Glaucoma/drug therapy , Humans
20.
Ger J Ophthalmol ; 1(1): 16-8, 1992.
Article in English | MEDLINE | ID: mdl-1477610

ABSTRACT

Cyclopentolate plasma levels were quantitated and heart rate and pupil size were monitored after ocular application of the drug to juveniles. In all, 12 children were given one 35-microliters eyedrop of either 1% cyclopentolate (n = 6) or placebo (n = 6) in randomized order in the lower cul-de-sac of one eye. A sensitive radioreceptor assay was used to determine the systemic drug absorption. With the exception of one child, detectable cyclopentolate concentrations were seen in plasma at as early as 3 min after the ocular drug application. There was a marked interindividual variation in peak plasma cyclopentolate concentrations ranging from undetectably low to 5.8 ng/ml (median, 2.9 ng/ml). In some children a second drug concentration peak was detected. Cyclopentolate increased the pupillary diameter from 4.8 +/- 1 mm before drug application to 8 +/- 0.9 mm at 30 min after administration, but the children's heart rate did not alter.


Subject(s)
Cyclopentolate/pharmacokinetics , Eye/metabolism , Absorption , Child , Cyclopentolate/administration & dosage , Female , Heart Rate/drug effects , Humans , Male , Ophthalmic Solutions , Pupil/drug effects , Radioligand Assay , Random Allocation , Strabismus/surgery
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