Thiol/Disulfide Balance in Older Patients with BCR-ABL Negative Myeloproliferative Neoplasms.

BACKGROUND: The trio Essential Thrombocytosis (ET), Polycythemia Vera (PV), and Primary Myelofibrosis (PM) are BCR-ABL negative myeloproliferative neoplasms. All three diseases have the risk of transforming into acute leukemia. Oxidative stress and some genetic mutations increase the risk of leukemic transformation. The median age in patients with ET, PV, and MF is around 64 years, and it is expected to exceed 65 in the coming years. Since oxidative stress increases with age, we aimed to evaluate the oxidative stress parameters in older patients with myeloproliferative neoplasms. METHODS: The study included a total of 160 patients (57 patients with Essential Thrombocytosis, 52 patients with Primary Myelofibrosis, and 51 patients with Polycythemia Vera) and 56 healthy controls, aged 65 and over. Ischemia Modified Albumin (IMA) and thiol parameters (native thiol, total thiol, and disulfide) were studied from serum samples taken at the time of diagnosis. RESULTS: The median age of the patients was 69 (65 - 85) years. Patients had higher levels of IMA and lower levels of thiol compared to the control group (p < 0.001). When evaluated according to disease subgroups, it was observed that the highest IMA levels and the lowest thiol levels were in patients with PM (p < 0.001). Higher IMA levels and lower native thiol levels were found in patients with the ASXL1 mutation (p < 0.001). CONCLUSIONS: Serum IMA and thiol levels are also significantly changed in older patients with BCR-ABL negative myeloproliferative neoplasia. Changes in these markers are independent of age. Disease-associated mutations such as ASXL1 can also affect the serum levels of these markers.

The Role of Optical Coherence Tomography Signal Strength in the Diagnosis and Follow-up of Patients with Posterior Capsular Opacification Treated with Nd:YAG Laser Capsulotomy

Objectives: To investigate the relationship between optical coherence tomography (OCT) signal strength (SS) and visual acuity in patients with posterior capsule opacification (PCO) and evaluate the effect of PCO on retinal thickness measurements. Materials and Methods: Forty-one eyes of 35 patients who were diagnosed with PCO were included in the study. Patients with any anterior or posterior segment pathology other than PCO were excluded. After ophthalmologic examination, pupil dilation was induced using 0.5% tropicamide and OCT images were acquired. The assessment was repeated 1 month after Nd:YAG laser capsulotomy and postoperative values were compared with baseline values. Results: The patients' mean best corrected visual acuity (BCVA) was 0.28±0.13 preoperatively and 0.78±0.09 postoperatively (p<0.0001). Strong positive correlations were observed between BCVA and SS both pre- and postoperatively (p<0.0001 and p=0.01, respectively). Central retinal thickness (CRT) and SS increased significantly postoperatively (p<0.0001 for both). OCT SS and CRT were strongly correlated preoperatively (p=0.001) but not postoperatively (p=0.46). Conclusion: OCT SS correlates with visual acuity in patients with PCO, and PCO can affect the accuracy of objective data obtained with OCT.

Evaluation of Ocular Complications by Using Optical Coherence Tomography in Children With Sickle Cell Disease Eye Findings in Children With Sickle Cell Disease.

OBJECTIVE: The aim of this study was to compare optical coherence tomography (OCT) findings in pediatric patients with sickle cell disease (SCD) and healthy individuals and to investigate associations between these data and the patients' systemic findings. MATERIALS AND METHODS: The study included 108 eyes of 54 patients with SCD with no visual symptoms and a control group consisting of 110 eyes of 55 healthy subjects with no systemic or ocular pathology. After best-corrected visual acuity assessment, the study participants underwent a complete ophthalmologic examination including intraocular pressure. After examination and pupil dilation induced with 1% tropicamide, 9×9 mm macular sections were obtained with spectral-domain OCT. The macular sections were evaluated according to Early Treatment Diabetic Retinopathy Study (ETDRS) map and internal and external retinal thicknesses were measured using the software included in the OCT device. RESULTS: The patient group showed significantly more foveal flattening, temporal thinning, and vascular tortuosity than the control group (P<0.0001 for all). Foveal width was significantly greater in the patient group (1592.39±175.56 µm) compared with the control group (1391.01±175.56 µm) (P<0.0001), whereas foveal depth was significantly lower in the patient group (121.15±26.83 µm) than in the control group (146.1±12.25 µm) (P<0.0001). The mean total retinal thickness was 253.53±22.31 µm in the patient group and 261.03±18.48 µm in the control group (P=0.007). Similarly, central retinal thickness was significantly lower in the patient group (219.35±10.53 µm) compared with the control group (235.32±12.51 µm) (P<0.0001). DISCUSSION: Our study shows that pediatric patients with SCD may have subclinical retinal involvement and that temporal thinning, in particular, is an important OCT finding. This strongly suggests that OCT imaging would be a beneficial addition to routine ophthalmologic examination in the diagnosis and follow-up of this patient group.

Intravitreal bevacizumab effects on VEGF levels in distant organs: an experimental study.

PURPOSE: The aim of this study was to determine the effects of single-dose intravitreal bevacizumab on the levels of vascular endothelial growth factor (VEGF) in serum and distant organs. METHODS: Adult New Zealand albino rabbits (n = 40) were divided into experimental and control groups. Experimental rabbits received a single 0.05 ml intravitreal injection of 1.25 mg bevacizumab (Avastin) into the right eye, and control rabbits (n = 8) received no injection. Following injection, group 1 rabbits (n = 8) were sacrificed on day 1, group 2 rabbits (n = 8) on day 7, group 3 rabbits (n = 8) on day 14, and group 4 rabbits (n = 8) on day 28; control rabbits were sacrificed on day 28. After sacrifice, samples of brain, heart, liver, kidney and blood were collected. Levels of VEGF in serum and tissue were measured using enzyme-linked immunosorbent assay. The presence of bevacizumab was evaluated by immunofluorescence staining in tissues. RESULTS: Positive bevacizumab immunoreactivity was observed in brain, heart and kidney. Serum VEGF levels significantly decreased in groups 3 and 4 compared with controls (p < 0.05). Liver VEGF levels significantly decreased in group 3 compared with controls (p < 0.05). CONCLUSIONS: Intravitreal bevacizumab not only may escape from the blood-retinal barrier and enter the general circulation, but also may be disseminated to distant organs. Our study demonstrates that a single dose of intravitreally injected bevacizumab decreases VEGF levels in serum and liver.