Light-Emitting Diode Laser Therapy for Hyperoxia-Induced Retinal Abnormalities.

Introduction: Hyperoxygenation is linked to numerous effects in a variety of organ systems. It can cause tissue damage by generating reactive oxygen species (ROS), increasing oxidative stress, and inducing cell death by apoptosis. The present study aimed to evaluate the effects of low-level laser therapy on the retina in response to acute hyperoxia in animals. Methods: A total of 70 Wistar albino rats were evaluated in the present study: 10 rats were designated as a control group, and the rest were exposed to hyperoxia (O2, 90%) for 3 days, 1 week, and 2 weeks (20 rats each). Each group was divided into two subgroups (n=10), one of which was designated as hyperoxia only. The other was treated with a 670 nm light-emitting diode laser (2 sessions/one week, ~ 9.0 J/cm2) in each eye. The animals were euthanized, and their retinas were dissected for analysis of protein content, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), total antioxidant capacity (TAC), hydrogen peroxide (H2 O2), malondialdehyde (MDA), and histological examination. Results: We found that two weeks of hyperoxia induced an increase in retinal protein content (P<0.001), an alteration in the intensities and molecular weights of protein fractions, a significant decrease in the TAC level (P<0.01), and a noticeable increase in H2 O2 and MDA levels (P<0.001). Histological examination revealed fragmentation of the photoreceptors and neovascularization in the outer and inner plexiform layers. Furthermore, the data showed remarkable improvement in the retinal protein contents, oxidative state, and retinal structure after light-emitting diode laser therapy. Conclusion: Light-emitting diode laser therapy was found to be a useful treatment paradigm for reducing hyperoxia-induced retinal damage.

Role of alkali metal oxide type on the degradation and in vivo biocompatibility of soda-lime-borate bioactive glass.

In this work, it is the first time to study the effect of replacing of Na2 O by a fixed amount of Li2 O or K2 O in soda-lime-borate glass on its in vivo biocompatibility. The glass composition was based on xM2 O-20x Na2 O20 CaO60 B2 O3 , (wt %), where, M2 OLi2 O and K2 O, and consequently, samples encoded BN100, BK50, and BL50. The degradation test was carried out in 0.25 M K2 HPO4 solution. The in vivo test was performed in the femoral bone defect of Sprague-Dawley adult male rat. Following up bone formation was conducted by the histological analyses and bone formation markers (alkaline phosphatase [ALP] and osteocalcin [OCN]). Furthermore, the glass effect on the liver and kidney functions was addressed in this study using (alanine transaminase [ALT] and aspartate transaminase [AST]) and (urea and creatinine), respectively. The results of the degradation test showed that the glass dissolution rate was increased by incorporating of K2 O, and its ion release was occurred by a diffusion-controlled process. Moreover, in vivo bioactivity test showed that serum activity of ALP, OCN level, and the newly formed bone was higher in BL50-implanted group than that of BN100 andBK50at 3 w and 6 w post-surgery. As well as, implantation of all glass samples in the femoral bone defect did not alter the liver and kidney functions. In conclusion, the synthesized borate glass was well served as a controlled delivery system for Li+ ion release, which enhanced bone formation as shown from the bone formation markers (ALP and OCN).

Endometrial histopathology, ovarian changes and bleeding patterns among users of long-acting progestin-only contraceptives in Egypt.

OBJECTIVE: To evaluate endometrial and ovarian effects, and bleeding patterns, among users of Depo-Provera(®), Norplant(®), and Implanon(®). STUDY DESIGN: One-hundred and fifty women, who had been using one of these long-acting progestin-only contraceptives (LAPCs) for at least the previous six months, with fifty in each of the groups, were assessed. RESULTS: All results are mentioned in the following sequence: (1) Depo-Provera(®), (2) Norplant(®), and (3) Implanon(®). Normal bleeding was reported by 0%, 52%, and 8%; amenorrhoea or infrequent bleeding by 68%, 24%, and 72%; and abnormal bleeding by 32%, 24%, and 20%, respectively (p < 0.001). Histological evaluation revealed an atrophic endometrium in 84%, 32%, and 28%, respectively (p < 0.0001); a progestin effect in 16%, 28%, and 62%, respectively (p < 0.0001), and a proliferative pattern in 0%, 40%, and 10%, respectively (p < 0.0001). Endometrial thickness was 3 ± 0.41 mm, 3.62 ± 0.65 mm, and 5.2 ± 0.84 mm, respectively (p < 0.0001). Follicular growth in the ovaries was observed at ultrasound in 12%, 40%, and 72%, respectively (p < 0.001). CONCLUSION: Bleeding patterns, endometrial thickness, ovarian activity, and endometrial histology among Egyptian users of LAPCs differed significantly depending on the nature of the contraceptive.