Impact of ultrasound and optical biometry on refractive outcomes of cataract surgery after penetrating keratoplasty in keratoconus

AIM: To analyse the impact of ultrasound and optical intraocular lens(IOL) calculation methods on refractive outcomes of cataract phacoemulsification performed after penetrating keratoplasty(PK) in keratoconus. METHODS: Phacoemulsification cataract surgery was performed on 42 eyes of 34 patients with keratoconus who had previously undergone PK. The IOL power was determined by using both standard and corneal topography-derived keratometry using the SRK/T formula. We used two independent methods-ultrasound biometry(UB) and interferometry [optical biometry(OB)] for IOL calculation. The analysed data from medical records included demographics, medical history, best corrected visual acuity(BCVA) on Snellen charts, technique of IOL calculation and calculation formula and its impact on final refractive result.RESULTS: BCVA ranged from 0.01 to 0.4(mean 0.09±0.19) before surgery and ranged from 0.2 to 0.7(mean 0.38±0.14) at 1 mo and from 0.2 to 1.0(mean 0.56±0.16)(P<0.05) at 3 mo, postoperatively. The refractive aim differed significantly from the refractive outcome in both the UB and OB groups(P<0.05). There was no statistically significant difference in the accuracy of the two biometry methods.CONCLUSION: The refractive aim in keratoconus eyes post-PK is not achieved with either ultrasound or OB.

Glycine supplementation reduces the severity of chemotherapy-induced oral mucositis in hamsters

Objective: Oral mucositis (OM) is a devastating toxicity associated with cytotoxic cancer therapy. The OM pathogenesis and the complex interactions occur in response to tissue insult. Application of this evolving model has aided in the development of mechanistically based therapies for the prevention and treatment of mucositis. The present study was to assess the effects of glycine supplementation on chemotherapy-induced oral mucositis. Methods: In a hamster cheek pouch model of chemotherapy-induced oral mucositis, one group of 20 animals received systemic glycine supplementation for 7 days, while another similar control group did not. Clinical mucositis severity and neutrophil infiltrate (on histology) were assessed by blinded examiners. Free radical production was measured as malondialdehyde (MDA) levels. Results: As compared to control animals, glycine-treated animals demonstrated a highly significant reduction in clinical severity of oral mucositis, neutrophil infiltrate, and MDA levels (p < 0.001 for all). Conclusions: Glycine supplementation reduces the severity of chemotherapy-induced oral mucositis in an animal model. This effect is at least partly mediated through inhibition of the inflammatory response and reduced production of damaging free radicals.

Sphere-forming-like cells(squamospheres) with cancer stem-like cell traits from VX2 rabbit buccal squamous cell carcinoma

Previous studies have demonstrated that spheroid type cells grown under suspension culture conditions have cancer stem cell（CSC） traits in a number of cancers, but this phenomenon has not yet been reported in the VX2 rabbit oral cancer model. Hence, this study aimed to study the spheroid cells from VX2 rabbit buccal squamous cell carcinomas（SCCs） and assess their CSC characteristics. Five adult male New Zealand white outbred rabbits were used to generate VX2 rabbit buccal SCC. Sphere-forming cell culture was performed for the VX2 rabbit buccal SCC specimens. The self-renewal capability; cluster of designation（CD） 44, CD133, acetaldehyde dehydrogenase 1（ALDH1）, B cell-specific Moloney murine leukemia virus integration site 1（Bmi-1）, Nestin, octamer-binding transcription factor 4（Oct4）and reduced expression protein-1（Rex-1） expression with reverse transcription-polymerase chain reaction（RT-PCR）; chemoresistance to cisplatin and 5-fluorouracil; and in vivo tumorigenicity of spheroid cell transplantation in nude mice were evaluated to determine the CSC characteristics of the resulting spheroid cells. We successfully obtained spheroid cells from the VX2 rabbit OSCC tissues. The spheroid cells exhibited CSC traits, including the expression of CSC and stem cell markers（CD44, Bmi-1, Nestin, Oct4 and Rex-1）, capacity to generate new spheroid colonies within 1 week of reseeding from single-dissociated spheroid cells, chemoresistance capacity and generation of tumour xenografts（with histological features resembling those of the original VX2 rabbit buccal SCC） from the transplantation of 103 undifferentiated spheroid cells into nude mice. In summary, we demonstrated that spheroid cells with CSC cell traits can be derived from VX2 rabbit buccal SCCs, indicating that this animal cancer model is applicable for studying CSCs in human oral cancers.

Anti-vascular endothelial growth factor and macular atrophy:an unanswered question

Does anti-vascular endothelial growth factor(VEGF)therapy lead to geographic atrophy?If so,does the number of injections or the duration of anti-VEGF therapy correlate with the risk of developing geographic atrophy?With intravitreal injections becoming the most common ophthalmic invasive procedure and an increasingly aging population,these questions really matter.

Effects of clinical dental implant abutment materials and their surface characteristics on initial bacterial adhesion

Initial bacterial adhesion on dental implant abutment is related to its surface chemical composition and physical characteristics.Selection of appropriate abutment materials resistant to bacterial adhesion is important for dental implant maintenance.The aim of present study was to evaluate the effect of different properties of abutment materials on initial bacterial adhesion in vitro.Polished zirconia(PZ group), polished titanium(PT group) and ground titanium(GT group) samples were prepared to simulate clinical dental implant abutments.Chemical compositions, morphology, roughness, hydrophilicity and surface free energy of materials were analyzed.Oral commensal bacterium Streptococcus mitis was used to evaluate initial bacterial adhesion via turbidity test and colony-forming unit counting.The results showed that GT group presented the highest roughness, hydrophilicity and surface free energy.After 6-h incubation, GT group showed the significantly highest adhered bacteria counts;while non-significant difference existed between PT and PZ groups.Within the clinically applicable range used in present study, the surface physical characteristics, instead of surface chemical composition, of dental abutment material have the pronounced influence on initial 6-h bacterial adhesion.

Therapeutic effect of Guijiajiao (Colla Carapacis et Plastri) on bone regeneration in rats and zebrafish

OBJECTIVE:To investigate the effect of Guijiajiao(Colla Carapacis et Plastri, CCP), the glue of tortoise shell, on bone regeneration in zebrafish and male Wistar rats.METHODS: In this study, we applied in vitro and in vivo models, tissue section analysis, and quantitative polymerase chain reaction to assess the effects of CCP on bone repair. MG-63 cells were used in alkaline phosphatase(ALP) activity and mineralization assays. Zebrafish and male Wistar rats were used to evaluate the effects of CCP on bone repair in vivo.RESULTS: A simple preparation of CCP promoted osteogenesis in vivo and in vitro, and promoted MG-63 cell proliferation as well as ALP activity and mineralization. In addition, CCP activated Akt and extracellular signaling-regulated kinase pathways and significantly increased the expression of ossification-related genes and proteins such as runt-related transcription factor-2, osteocalcin, and osteopontin. The in vivo results revealed promotion of osteogenesis by immersing zebrafish in CCP for 72 h.An oral dose of 1.25 g/kg CCP significantly improved skull defects in rats, which was accompanied by an increase in serum ALP levels.CONCLUSION: One of the ingredients of Guilu Erxianjiao(tortoise shell and deer horn formula) pro-vides a practical alternative therapy for bone regeneration.

Environmental exposure to cadmium but not lead is associated with decreased semen quality parameters:quality regionalism of sperm properties

Environmental factors may negatively contribute to a progressive worsening of semen quality,and differences in semen quality may result from different environmental exposures(regional differences)or lifestyle differences.Heavy metals are factors with a confirmed negative influence on male fertility.Among them,lead and cadmium are commonly found in human surroundings.Thus,we analyzed semen parameters(according to the World Health Organization 2010 recommendations)and semen lead and cadmium concentrations in 188 men from two different regions in Poland,a typical agricultural area and an industrial area,in couples that had been diagnosed with infertility.The assays were performed using flameless electrothermal atomic absorption spectrometry.In the statistical analysis,regional comparisons and then taxonomic comparisons based on three parameters(age,semen concentration,and sperm morphology)were applied.We showed that more cadmium than lead accumulated in semen,a higher cadmium concentration was observed in semen obtained from men from the agricultural region,and better semen quality and lower cadmium concentrations were found in the semen of men from the industrial,more polluted region.We thus showed an existing regionalism in the sperm quality properties.However,semen parameters such as morphology and progressive and nonprogressive motility followed the same trends,regardless of the patient’s age,region,or class.We could conclude that the environment has a minor impact on sperm morphology and progressive and nonprogressive motility and that other existing factors could have an indirect influence on semen quality.