A pilot study of viscoelastic agent to prevent recurrent vitreous hemorrhage after vitrectomy for proliferative diabetic retinopathy.

BACKGROUND: To evaluate the possibilty of preventing recurrent vitreous hemorrhage (RVH) after vitrectomy in proliferative diabetic retinopathy (PDR) patients with unabsorbed vitreous hemorrhage (VH) by intravitreal injection of viscoelastic agent (VA) at the end of the surgery and compared its effect with triamcinolone acetonide (TA). METHODS: This was a pilot prospective, observational study. PDR patients with VH who underwent vitrectomy were assigned to 3 groups according to the tamponade applicated at the end of the surgery, including VA group (intravitreally injected 1 ml VA if the retina was prone to bleed during the operation), TA group (intravitreally injected 2 mg TA when there was much exudates), or balanced salt solution (BSS) group (no tamponade). Then postoperative follow-up was performed routinely until 6 months after surgery. The primary outcome was the incidence of RVH, secondary outcome were the best-corrected visual acuity (BCVA) and introcular pressure (IOP). Cataract formation and other complication were also assessed. RESULTS: A total of 68 eyes, from 68 patients, were included. 18,18,32 eyes were enrolled in the VA group, TA group and BSS group, respectively. The integral incidence of RVH after vitrectomy was 5.6%, 5.6% and 12.5% respectively (P = 0.602). There was no early RVH in VA or TA group, whereas 3 early RVHs were identified in BSS group, however there was no significant difference (P = 0.171). Every group had one late RVH case. In all groups, final BCVA showed significant improvement compared to baseline. BCVA at any postoperative visit showed no significant differences among 3 groups. Mean IOP was higher 1 week after surgery in VA group compared with the other groups; however, in other times the differences were not significant. No cataract formation and other complication was noted in 3 groups. CONCLUSION: Intravitreal injection of VA or TA at the end of vitrectomy for PDR patients with unabsorbed VH tend to reduce the incidence of early RVH after vitrectomy similarly. As VA was preferred to applicate in the eyes that were prone to bleed, intravitreal injection of VA at the end of vitrectomy might be a promising method for preventing RVH in PDR patients.

Ultrastructural study of closed macular hole- preliminary application of a novel high magnification module combining with OCT.

BACKGROUND: As a novel high magnification module (HMM) combining with OCT (OCT-HMM) is able to detect the microstructure of retina, we apply it to explore the ultrastructure of the macula after closure of the idiopathic macular hole (IMH) by surgery. METHODS: This is an observational case series study in which patients with full-thickness IMHs who had undergone successful macular closure by vitrectomy and internal limiting membrane peeling and healthy subjects were recruited. After comprehensive ophthalmic examinations, the images of macular area were obtained and collected by professional operators using OCT-HMM. Then images were independently analyzed by 4 masked vitreoretinal specialists. RESULTS: A total of 24 IMH eyes and 42 healthy eyes were examined. HMM images were obtained in 10 IMH eyes. Among them, 4 eyes whose macula closed completely with recovery of photoreceptor layer presented a dark arc nasal to the fovea, oriented to the optic, and the notch of arc faced temporally. Six eyes in which the macula closed incompletely with photoreceptor cells loss revealed a dark ring with uneven bright spots inside. The other 14 eyes failed to obtain clear images by OCT-HMM. The contra lateral eyes of the patients and the healthy subjects' eyes succeeded to obtain the HMM images which displayed evenly grey background thickly covered with tiny bright dots that was in similar size and evenly and widely distributed and there no dark arc or ring. OCT B-scan and IR images could be acquired in all of the IMH and healthy eyes. CONCLUSION: The preliminary application of HMM has supplied us a brand-new insight into the microstructure of closed IMH. A dark arc sign could be detected with OCT-HMM in the macula which was functionally closed after surgery that was probably the healing mark on a microstructure photoreceptors level. Its existence and shape indicated that the functional closure followed by a retinal displacement mainly horizontally from temporal side to nasal side but not symmetric centripetally.

Effects of Foxp3 gene modified dendritic cells on mouse corneal allograft rejection.

OBJECTIVE: To investigate the effect of Foxp3 gene modified dendritic cells (Foxp3 + DC) on allogeneic T cells proliferation and to study the effect of Foxp3 + DC on corneal allograft rejection. METHODS: Lentivirus-Foxp3 was transfected into DC2.4 cells, as Foxp3 + DC cells. 42 BALB/c mice were randomly divided into: Group A (n = 6), normal group; Group B (n = 12), Group C (n = 12) and Group D (n = 12), allograft groups, were treated with normal saline, DC2.4, Foxp3 + DC by intraperitoneal injection, respectively. RESULTS: Compared with the control group, Foxp3 protein in the Foxp3 + DC cells increased significantly (P < 0.05); the expressions of CD80 and CD86 immunophenotypes of Foxp3 + DC cells decreased significantly (P < 0.05); IL-12 secretion reduced (P < 0.05), but IL-10 secretion was promoted (P < 0.05). The average transplant survival time in Group B was (14.833 ± 1.472) d, and Group C and Group D led to a statistically significant prolongation of transplant survival to (17.667 ± 1.366, 23.000 ± 2.000) d (P < 0.05) respectively. 14 d after transplantation, as compared with Group C and D, the expressions of IFN-γ in grafts markedly increased in Group B. 14 d after transplantation, as compared with Group B, the expressions of Foxp3 mRNA, IDO mRNA in grafts decreased remarkably in Group C and D (P < 0.05); as compared with Group C, the expressions of Foxp3 mRNA, IDO mRNA in grafts decreased remarkably in Group D (P < 0.05). CONCLUSION: Foxp3 + DC cells reduce the expression of costimulatory factors, reduce the secretion of IL-12, promote IL-10 production and inhibit the stimulation of alloreactive T cell proliferation response capacity. Foxp3 + DC cells play important roles in inhibiting corneal allograft immune response and prolonging graft survival time.

Ocular trauma score in transferred fireworks-related ocular injuries: a case series.

BACKGROUND: Our aim was to review the characteristics of transferred fireworks-related ocular damage and to evaluate the prognostic value of the ocular trauma score (OTS) for these injuries. METHODS: This study included 22 transferred patients (19 male, 3 female; mean age 22.6±14.9 years) (25 eyes). The data were retrospectively reviewed, including the characteristics of the geography, types of fireworks, status of injuries, therapeutic procedures, and the best-corrected visual acuity (BCVA). All the injured eyes were classified using the OTS at the time of the initial examination. RESULTS: Twenty eyes (80%) were in OTS category 1, three eyes (12%) were in OTS category 2, and two eyes (8%) were in OTS category 3. All cases received surgical therapy. Six eyes (24%) were enucleated, four (16%) of which achieved an improvement in their final BCVA. There was a statistically significant improvement in final BCVA between OTS category 1 and the other two OTS categories (p=0.016). CONCLUSION: The aforementioned transferred fireworks-related ocular injury cases occurred mainly in young adults, men and active participants, all of which incurred serious vision loss and blindness. The OTS is quite effective for classifying the status and estimating the prognosis of transferred fireworks-related ocular injuries.

Changes in objective vault and effect on vision outcomes after implantable Collamer lens implantation: 1-year follow-up.

PURPOSE: To investigate the changes in vault and the effect on visual outcomes 1 year after implantable Collamer lens (ICL) implantation. METHODS: In this retrospective study, 127 eyes of 66 patients undergoing ICL implantation were examined both before and up to 1 year after the surgery. The examination contents included white-to-white (WTW) diameter, central vault of the ICL (distance between posterior surface of ICL and anterior surface of crystalline lens), refractive error, and wavefront high-order aberration (HOA). All statistical analyses were performed using SPSS 13.0 software. RESULTS: A significant decrease in vault was noted up to 1 month, after which the value stabilized (p=0.001). The moderate vault decreased significantly after the first 3 months postsurgery (paired-samples t test, p<0.05). Low vault showed a tendency to increase and high vault showed a tendency to decrease, but not significantly, over time. There was no statistically significant correlation between the amount of vault and the refractive error (Pearson correlation coefficient R=0.111, p=0.473) and there was a statistically significant correlation between the vault and HOAs (R=0.304, p=0.024). CONCLUSIONS: Implantable Collamer lens vault over the crystalline lens had the tendency toward a slight decrease with time and did not significantly affect the vision outcome 1 year after surgery.

[Construction of lentiviral expression vector containing Foxp3 gene and its expression in DC2.4 cell line].

AIM: To construct a Foxp3 lentiviral vector and transfer it into DC2.4 cells, which provides Foxp3+DC cells for further study on its immune modulation. METHODS: We cloned mouse Foxp3 gene into lentiviral vector(pGC-FU) and acquired the plasmid pGC-FU-Foxp3. PCR and sequencing analysis were made for verifying the positive clones. The virus packaging plasmids(pGC-FU-Foxp3, pHelper1.0 and pHelper2.0) were contransfected into 293T cells, and the Lentivirus-Foxp3 was harvested from 293T cells. The Lentivirus-Foxp3 was used to infect DC2.4 cells in vitro and the expression of Foxp3 in infected DC2.4 cells was detected with flow cytometry(FCM). RESULTS: PCR and sequencing revealed that the pGC-FU-Foxp3 plasmid was correctly constructed. The Lentivirus-Foxp3 with a titer of 2×10(8); TU/mL was successfully packaged. Foxp3 expression in DC2.4 cells infected with the Lentivirus-Foxp3 was increased significantly compared with negative control lentivirus. CONCLUSION: The pGC-FU-Foxp3 plasmid has been successfully constructed and the Lentivirus-Foxp3 has been successfully packaged. Foxp3 can be enhanced in DC cells infected with the Lentivirus-Foxp3.

Experimental study of the mechanism of tolerance induction in dexamethasone-treated dendritic cells.

BACKGROUND: The aim of this study was to investigate the mechanisms underlying tolerance induction of dexamethasone (Dex)-treated dendritic cells (DCs). MATERIAL/METHODS: Well-grown DC2.4 cells were randomly assigned to receive control, 50 µg/L, 100 µg/L, or 200 µg/L of dexamethasone and then were cultured for 6 days. The expressions of CD80, CD86, galectin-9, and PD-L1 on the surface of DC2.4 cells were analyzed with flow cytometry and the level of IL-12 secreted by DC2.4 cells was determined by ELISA. The stimulating activity of DC2.4 cells on allogeneic T cells was assessed with mixed lymphocyte reaction. Dexamethasone-treated DC2.4 cells were co-cultured with allogeneic splenic lymphocytes and the Foxp3 expression in naive T lymphocytes was determined with flow cytometry. RESULTS: Compared with the control group, the expressions of CD80, CD86, galectin-9, and PD-L1 on the surface of DC2.4 cells exposed to different doses of dexamethasone showed no significant changes; however, dexamethasone treatment significantly reduced IL-12 secretion and inhibited DC2.4's stimulation on the proliferation of allogeneic T lymphocytes. Moreover, dexamethasone-treated DC2.4 cells effectively promoted FOXP3 expression in naive T lymphocytes. CONCLUSIONS: DC2.4 is a stable cell line with high expressions of CD80, CD86, and PD-L1. Dexamethasone does not significantly change the cell phenotype of DC2.4 cells, but inhibits the secretion of IL-12 cytokine and attenuates DC2.4's stimulation of the proliferation of allogeneic T cells. Dexamethasone-treated DC2.4 cells also effectively promote FOXP3 expression in naive T lymphocytes.

[Outcome after treatment of myopia with implantable Collamer lens].

OBJECTIVE: To evaluate the efficacy, predictability, stability, and safety of the surgical correction myopia using implantable Collamer lenses (ICL) in phakic eyes. METHODS: A prospective study was performed to analyze 91 eyes of 48 patients who had the implantation of ICL for the treatment of myopia from July 2008 to February 2010. Patients were examined preoperatively and followed at 1 week, 1, 3, 6, and 12 months postoperatively. The examinations included the uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), refraction, contrast sensitivity, wavefront aberration, intraocular pressure, space between crystal lens and intraocular lens (vault), endothelial cell density (ECD), anterior chamber depth (ACD), surgical complication, etc. RESULTS: Successful implantation was achieved in all patients. The mean follow-up time was (9.54 ± 4.12) months (SD)(range 1 to 12 months). The mean preoperative SE was -12.38 diopters (D) (range -5.0D to -23.0D). Postoperatively, UCVA was maintained or improved in all eyes. UCVA achieved 1.0 in 58 eyes (64%) and BCVA gained more than 1 line in 69 eyes (75.9%). The glare and no glare contrast sensitivity were improved at 3cd, 12cd and 18cd, with the exception of 6cd. The aberration decreased in RMS, spherical and coma. Post operative ACD (1 week after operation) diminished 8.92% as compared with the preoperative ACD. The mean vaulting was (452 ± 216.38) µm (6 months) and ranged 130 - 1080 µm at different follow-up periods. There was no statistically significant difference in vaulting between postoperative data at different periods (t = 0.200, P > 0.05). The mean postoperative ECD decreased but had no statistically difference compared with the preoperative ECD. ACD decreased 31% after surgery in 2 eyes (2.1%). Transient high IOP was observed in 13 eyes (2.1%) one week after the operation. CONCLUSION: These results indicate that ICL implantation in the treatment of myopia is efficient, predictable, safe, and reliable.

[Effects of anti-CD25 monoclonal antibody on the level of cytokines in aqueous humour after rat penetrating keratoplasty].

OBJECTIVE: To investigate the toxicity of anti-CD25 monoclonal antibody (mAb) to rat cornea and its effects on the cytokines in the aqueous humour after penetrating keratoplasty (PKP), thereby evaluating the effect of anti-CD25 mAb in preventing corneal allograft rejection. METHODS: The corneal toxicity of anti-CD25 mAb at 50, 100 and 200 microg administered via subconjunctival injection was evaluated in 12 SD rats by histological examination and transmission electron microscopy. Another 93 SD rats were randomized into 5 groups, and transplantation of corneal allograft from Wistar rats was performed in 4 groups with the other group as the normal control. The 4 allograft groups were treated with saline, 100 microg anti-CD25 mAb, 100 microg anti-CD25 mAb with 50 microg dexamethasone, and 50 microg dexamethasone, respectively. The graft rejection was observed, the aqueous humour levels of IFN-gamma and IL-4 were measured with ELISA, and IFN-gamma mRNA expressions in the grafts detected with RT-PCR. RESULTS: anti-CD25 mAb at 50 or 100 microg did not show significant toxicity on the cornea, but at 200 microg, the mAb caused swelling of the corneal stromal cells and endothelial cells. After corneal allograft transplantation, a significant delay in allograft rejection was observed in the 3 groups with mAb or dexamethasone treatment as compared with that in saline group (P<0.05). IFN-gamma mRNA expression in the allograft on days 11 after PKP and in the aqueous humour on days 6 and 11 was markedly increased in saline group compared with that in the 3 treatment groups (P<0.05). The mean IL-4 level in the aqueous humour was significantly higher in the mAb group than in saline group (P<0.05), but markedly lower in anti-CD25 mAb+dexamethasone and dexamethasone groups than in anti-CD25 mAb group (P<0.05). CONCLUSIONS: Anti-CD25 mAb at 20 and 100 microg does not obviously affect the rat corneas. Anti-CD25 mAb inhibits IFN-gamma expression and promotes IL-4 the expression to reduce corneal allograft rejection, whereas anti-CD25 mAb with low-dose dexamethasone inhibits both IFN-gamma and IL-4 expressions to more effectively promote the graft survival.

[Effect of IL-1 receptor antagonist on cell apoptosis in rat corneal grafts].

AIM: To observe the apoptosis of cells in rat corneal grafts at acute rejection phase and explore the effects of IL-1 receptor antagonist (IL-1ra) on cell apoptosis. METHODS: The penetrating corneal transplantation model was established. Corneal grafting was divided into four groups, namely, normal Wistar rat control group (no grafting, group A), isograft (Wistar rat-->Wistar rat, group B), allograft (Wistar rat-->SD rat) with normal saline treatment (group C) and allograft (Wistar rat-->SD rat) with IL-1ra treatment (group D). Cell apoptosis in corneal grafts was detected by TUNEL staining at 7 d, 10 d and 14 d after transplantation, and an automatic image analyzer was used to analyze the results, which were expressed as positive unit (PU). The changes of cellular ultrastructure in corneal grafts were observed under transmission electron microscope. RESULTS: (1)The average survival time of corneal grafts in C and D groups was (10.38+/-1.85) d and (13.56+/-1.94) d, respectively, with significant difference (P<0.01). (2)As compared with normal and non-rejected corneas, cell apoptosis and necrosis commonly existed in corneal grafts which rejection had occur. (3)In normal corneas, there were merely a very small number apoptotic cells in epithelial laminal, and apoptotic cells were found hardly in stromal laminal and endothelial cell layers. However, sporadic apoptotic cells were found in all layers of corneal grafts in B, C and D groups at 10 d after transplantation, the average PU being of no notably difference (P>0.05). Apoptosis obviously increased in nearby regions of wound and central area of corneal grafts in C and D groups, especially in C group. The apoptotic cells were distributed mainly in basal layer of epithelial cells and stroma of superficial layer. CONCLUSION: Cell apoptosis plays an important role in corneal graft rejection reaction. IL-1ra treatment can prolong the survival time of corneal grafts by means of suppression of cell apoptosis in corneal grafts.