"iDoctor – Medical Blog"

Purpose: To evaluate the influence of haemorheopheresis on anatomical and functional findings in patients with soft-drusen maculopathy.Methods: We investigated 29 eyes (16 patients) and randomized 25 eyes (16 controls) with soft-drusen maculopathy [soft, confluent and reticular drusen, drusenoid retinal pigment epithelium detachment (RPED)]. Each patient received a series of eight haemorheophereses (cascade filtration of 1.5 plasma volume) within 10 weeks. The patients were followed up using Early Treatment Diabetic Retinopathy Study (ETDRS) charts, optical coherence tomography, fluorescein angiography, electroretinography and measurements of pulsed ocular blood flow.Results: After the procedures, there was a substantial reduction in rheologically active substances [lipoproteins, [alpha]2-macroglobulin, immunoglobulin M (IgM), fibrinogen], plasma and blood viscosity. At the 1.5-year follow-up, we noticed soft drusen absorption; reattachment of drusenoid RPED and stabilization or improvement of visual acuity occurred in 72% of patients in comparison to only 39% of patients in the control group. Full-field electroretinograms showed significantly higher scotopic activity of treated patients in comparison with the control group, and mainly insignificant differences in photopic activity between both groups. Despite the significant increase of activity in the paramacular retina in treated patients, the differences in amplitudes of multifocal electroretinography (mfERG) average responses were insignificant between groups.Conclusion: Haemorheopheresis seems to be capable of changing the activity of promoters of the natural course of soft-drusen maculopathy, its development and progression. Visual acuity and electrical activity of the retina can be stabilized or even improved. The therapy has been shown to be effective and safe.

Purpose: To compare the visual refractive outcome and complication of laser in situ keratomileusis (LASIK) carried out with a Carl Zeiss-Meditec MEL-70 Excimer laser and a MEL-80 laser for treatment of high myopia.Methods: Journal records of 680 consecutive eyes that underwent LASIK with a Schwind Supratome microkeratome and a MEL-70 Excimer laser (Group A), or a Moria M2 microkeratome and a MEL-80 Excimer laser (Group B) were reviewed. Manifest refraction, uncorrected and best spectacle-corrected visual acuity (BSCVA), corneal topography and central corneal thickness (CCT) were recorded before and 3 months after treatment. Pre- and postoperative complications, visual and refractive outcome and frequency of retreatments were registered.Results: Mean preoperative spherical equivalent refraction was [minus]8.52 dioptres ([minus]5.50[ndash][minus]18 dioptres), and the mean attempted laser correction was [minus]8.02 dioptres ([minus]5.50[ndash][minus]11 dioptres). Three months after LASIK, the average treatment error (difference between achieved and attempted correction) was 1.20 (SD = 1.19) dioptres of under correction in Group A and 0.52 (SD = 1.00) dioptres in Group B. Four eyes lost more than two lines of BSCVA (0.6%). In 110 eyes (16%), a re-LASIK procedure was performed to reduce remaining myopia after the primary procedure.Conclusions: Laser in situ keratomileusis treatment for high myopia can effectively reduce high degrees of myopia. Under correction was observed in both treatment groups but Group B has a slightly better predictability. Significant loss of BSCVA occurs infrequently after LASIK for even considerable grades of myopia (0.6% in each group).

Purpose: Retinal vessel responses to flickering light are different in various systemic and ocular diseases and can be improved after successful therapy. We investigated retinal vessel response to flickering light in age-related macular degeneration (AMD) patients before and after treatment with a single intravitreal bevacizumab (Avastin®) injection.Methods: In 10 patients with exudative AMD [age: median (1.quartile; 3.quartile) 76.0 (73.5; 80.0) years], retinal vessel reactions were examined by Dynamic Vessel Analyser (DVA) before and 3 months after a single intravitreal application of bevacizumab (1.25 mg). A baseline measurement was followed by three consecutive monochromatic flicker stimulations (530[ndash]600 nm, 12.5 Hz, 20 seconds). Temporal retinal vessel reaction was analysed and compared with the reaction in healthy controls.Results: Mean arterial dilation at the end of flicker was not different in all groups. For veins this parameter amounted to: pre-treatment, 2.6 (1.7; 3.9)%; post-treatment, 2.9 (2.4; 4.0)%; control, 4.3 (3.2; 5.7)%; significant: pre-treatment [ndash] control (Dunnett’s procedure, p < 0.05). Maximal dilation occurred in arteries at: pre-treatment, 17.5 (14.8; 32.5) seconds; post-treatment, 18.0 (16.6; 30.6) seconds; control, 14.5 (10.8; 17.3) seconds. Both AMD groups were slower (p < 0.05): in veins at 17.0 (14.5; 20.0) seconds, 12.8 (8.6; 14.8) seconds and 18.5 (17.1; 19.9) seconds, respectively; significant post-treatment [ndash] control (p < 0.05). In the post-treatment AMD group arterial constriction after stimulation occurred more slowly compared with the control group (p < 0.05).Conclusion: Dynamic retinal arterial and venous reactions to flickering light are altered in AMD compared with controls. Three months after a single injection of a vascular endothelial growth factor inhibitor, the investigated retinal dynamic vascular parameters were not altered in our study.

Purpose: To determine the concentration of vascular endothelial growth factor (VEGF) in the aqueous humour of eyes with myopic choroidal neovascularization (mCNV).Methods: Aqueous humour samples were obtained from 21 eyes of 21 patients with mCNV and from 21 eyes of 21 patients with cataract without CNV or other ocular or systemic diseases (control group). The VEGF concentration in the aqueous humour was measured using an enzyme-linked immunosorbent assay.Results: The VEGF concentrations in the aqueous humour of eyes with mCNV ranged from < 20.6 to 200 pg/ml (median 35 pg/ml). The concentrations in the control group ranged from 26 to 218 pg/ml (median 100 pg/ml). The difference between the two VEGF concentrations in the aqueous humour was significant (p < 0.001, Mann[ndash]Whitney rank sum test).Conclusion: The VEGF concentration in the aqueous humour of patients with mCNV is lower than in normal controls. VEGF might localize in or around the CNV in eyes with mCNV.

Purpose: To investigate the evolution of cataract development and glutathione redox balance in the rat lens after in vivo close-to-threshold dose exposure to ultraviolet radiation (UVR) around 300 nm.Methods: Three groups of 10 Sprague[ndash]Dawley rats were unilaterally exposed to 8 kJ/m2 UVR-300 nm for 15 min, and a fourth group of 10 rats was kept without UVR exposure as nonexposed control animals. The exposed animals were killed at 1, 3 and 7 days after exposure. Both lenses from all animals were extracted and photographed and the intensity of forward light scattering was measured quantitatively. Thereafter, the lenses were homogenized. The concentration of reduced glutathione (GSH) and oxidized glutathione (GSSG), and the activity of glutathione reductase (GR) and glutathione peroxidase (GPx), respectively, were determined spectrophotometrically. The mean paired differences between exposed and nonexposed lenses were used as primary data in the statistical analyses.Results: All exposed lenses developed cataract. Lens light scattering increased throughout the 7 days after UVR exposure. GSH concentration and GPx rate transiently increased at 1 day after exposure and then decreased throughout follow-up, with GSH concentration having a negative balance at the end. GSSG concentration and GR activity did not change after UVR exposure.Conclusion: In vivo close-to-threshold UVR exposure induces a gradual increase in rat lens opacification/cataract development and time dependently alters the redox balance in the lens.

• Content Type Journal Article
• Category Original Paper
• DOI 10.1007/s10464-009-9292-2
• Authors
  • Beth S. Catlett, DePaul University Program Women’s and Gender Studies 2320 N. Kenmore, 571 SAC Chicago IL 60614 USA
  • Michelle L. Toews, Texas State University Department of Family and Consumer Sciences 601 University Drive San Marcos TX 78666 USA
  • Vanessa Walilko, DePaul University Program Women’s and Gender Studies 2320 N. Kenmore Chicago IL 60614 USA

• Journal American Journal of Community Psychology
• Online ISSN 1573-2770
• Print ISSN 0091-0562

• Content Type Journal Article
• Category Original Paper
• DOI 10.1007/s10464-009-9281-5
• Authors
  • Roderick J. Watts, Georgia State University Department of Psychology Atlanta GA USA

• Journal American Journal of Community Psychology
• Online ISSN 1573-2770
• Print ISSN 0091-0562

• Content Type Journal Article
• Category Original Paper
• DOI 10.1007/s10464-009-9293-1
• Authors
  • Jessica Ball, University of Victoria School of Child and Youth Care Box 1700 STN CSC Victoria BC V8W 2Y2 Canada

• Journal American Journal of Community Psychology
• Online ISSN 1573-2770
• Print ISSN 0091-0562

Saturated fat, carbohydrate, and cardiovascular disease.

Am J Clin Nutr. 2010 Jan 20;

Authors: Siri-Tarino PW, Sun Q, Hu FB, Krauss RM

A focus of dietary recommendations for cardiovascular disease (CVD) prevention and treatment has been a reduction in saturated fat intake, primarily as a means of lowering LDL-cholesterol concentrations. However, the evidence that supports a reduction in saturated fat intake must be evaluated in the context of replacement by other macronutrients. Clinical trials that replaced saturated fat with polyunsaturated fat have generally shown a reduction in CVD events, although several studies showed no effects. An independent association of saturated fat intake with CVD risk has not been consistently shown in prospective epidemiologic studies, although some have provided evidence of an increased risk in young individuals and in women. Replacement of saturated fat by polyunsaturated or monounsaturated fat lowers both LDL and HDL cholesterol. However, replacement with a higher carbohydrate intake, particularly refined carbohydrate, can exacerbate the atherogenic dyslipidemia associated with insulin resistance and obesity that includes increased triglycerides, small LDL particles, and reduced HDL cholesterol. In summary, although substitution of dietary polyunsaturated fat for saturated fat has been shown to lower CVD risk, there are few epidemiologic or clinical trial data to support a benefit of replacing saturated fat with carbohydrate. Furthermore, particularly given the differential effects of dietary saturated fats and carbohydrates on concentrations of larger and smaller LDL particles, respectively, dietary efforts to improve the increasing burden of CVD risk associated with atherogenic dyslipidemia should primarily emphasize the limitation of refined carbohydrate intakes and a reduction in excess adiposity.

PMID: 20089734 [PubMed - as supplied by publisher]

Comparing the glucose kinetics of adolescent girls and adult women during pregnancy.

Am J Clin Nutr. 2010 Jan 20;

Authors: Thame MM, Fletcher HM, Baker TM, Jahoor F

BACKGROUND: Fetal energy demands are met mostly from oxidation of maternally supplied glucose. In pregnant adults this increased glucose requirement is met by an increase in gluconeogenesis. It is not known, however, whether, like their adult counterparts, pregnant adolescent girls can increase gluconeogenesis-hence, glucose production. OBJECTIVE: Our objective was to measure glucose kinetics in 8 pregnant adolescents and 8 adult women. DESIGN: We measured glucose kinetics after an overnight fast by using a primed-constant 6-h U-(13)C-glucose infusion at the end of trimester 1 and early trimester 3. RESULTS: From trimester 1 to trimester 3, whole-body glucose production increased significantly in both groups (P < 0.01). However, whereas the weight-specific rate in the adults increased by 18.2%, it increased by only 14.3% in the adolescents. In the adults, the increase in whole-body glucose production was largely due to a significant increase (P < 0.01) in the rate of gluconeogenesis, but in adolescents there was no change in whole-body gluconeogenesis, and weight-specific gluconeogenesis actually decreased by 11.7%. In both groups, the rate of whole-body glycogenolysis increased significantly (P < 0.05) in trimester 3, and in adolescents, it increased by 95%. CONCLUSIONS: These findings suggest that, in the fasted state in late pregnancy, pregnant adolescents cannot increase weight-specific glucose production by the same magnitude as their adult counterparts. Furthermore, whereas adult women increase glucose production primarily through gluconeogenesis, adolescents do so through glycogenolysis.

PMID: 20089733 [PubMed - as supplied by publisher]