A modified chondroitin sulfate aldehyde adhesive for sealing corneal incisions

PURPOSE: To compare a modified chondroitin sulfate aldehyde adhesive with standard sutures for sealing corneal incisions. METHODS: A keratome knife was used to create non-self-sealing, uniplanar, 3-mm, clear corneal incisions in enucleated rabbit eyes (n = 18). The wounds were sealed with either a chondroitin sulfate-aldehyde adhesive (n = 8), three 10-0 nylon sutures (n = 5), or one 10-0 nylon suture (n = 5). Wound stability was tested by filling the globes with balanced salt solution through an anterior chamber port and slowly increasing the IOP. The pressure changes were monitored with a digital manometer connected to the anterior chamber, and leak pressure was recorded for each eye. Confocal microscopy was performed on the glued eyes, to document the glue distribution along the wound. RESULTS: The mean leak pressures in the single-suture and three-suture subgroups were 26.4 +/- 6.0 and 44.3 +/- 8.2 mm Hg (SD), respectively. The maximum IOP achieved in eyes that received the glue was 104.7 mm Hg with a mean of 101.4 +/- 3.2 mm Hg. None of the eyes in which glue was used showed leakage. At confocal microscopy, the glue was distributed inside the wound edges as a homogeneous thin layer of a less dense signal than that of the stroma. CONCLUSIONS: A novel chondroitin sulfate-aldehyde adhesive was shown to be effective ex vivo for sealing corneal incisions in rabbit eyes and was superior to sutures for this purpose.     

Laparoscopic versus open appendectomy for the obese patient: a subset analysis from a prospective, randomized, double-blind study

Background  

The clinical outcomes for patients randomized to either open or laparoscopic appendectomy are comparable. However, it is not known whether this is true in the subset of the adult population with higher body mass indexes (BMIs). This study aimed to compare the outcomes of open versus laparoscopic appendectomy in the obese population.     

Dimeric naphthoquinones, a novel class of compounds with prostate cancer cytotoxicity

What’s known on the subject? and What does the study add? Sexual function is often impaired after radical prostatectomy (RP) resulting in reduced sexual activity and sexual bother. The main focus in the literature concerning sexual adverse effects has been on erectile dysfunction and impairment of sexual function rather than the actual sexual bother it causes, although the sexual bother is most important to the individual patient’s quality of life. The relation between these measures, and in particular pre‐operative prediction of post‐operative sexual bother, has only been studied limitedly and with varying results. Some studies have found good mental health, low levels of pre‐operative sexual bother, and higher education to be associated with absence of post‐operative sexual bother, but another study could not identify any pre‐operative predictors of a post‐operative sexual bother. Severe sexual bother after RP were reported by 64% to 95% of the patients three years after operation, and the prevalence was associated with the level of pre‐treatment sexual bother and pre‐operative nerve‐preservation. On the other hand, others have reported that only 43% of men have sexual bother 2 years after RP. However, none of these studies stratified patients according to their pre‐operative sexual activity and most of them were American. It has been shown that American findings concerning sexual bother may not always be valid for non‐American patients due to differing sex role expectations thus warranting the need for more non‐American studies. This study has shown that two thirds of patients experienced sexual bother one year after RP. We have identified patients with increased risk of experiencing overall sexual bother post‐operatively: those who report pre‐operative sexual bother, those who are sexually active before RP, and those who display neurotic personality‐traits. Another important finding was that the proportion of patients who experienced bother relevant to having impaired post‐operative SF was significantly higher among pre‐operatively sexually active patients than those who had been inactive. This study adds knowledge that patients’ pre‐operative sexual activity, sexual bother and personality should be taken into account to be able to give individualized information about the risk of getting sexual bother after RP.

OBJECTIVES

• ? To evaluate the cytotoxicity of dimeric naphthoquinones (BiQs) in prostate cancer cells.
• ? To assess the interaction of dimeric naphthoquinones with common therapies including radiation and docetaxel.

MATERIALS AND METHODS

• ? The cytotoxicity of 12 different dimeric naphthoquinones was assessed in androgen‐independent (PC‐3, DU‐145) and androgen‐responsive (LNCaP, 22RV1) prostate cancer cell lines and in prostate epithelial cells (PrECs).
• ? BiQ2 and BiQ11 were selected for determination of dose response, effects on colony formation and initial exploration into mechanism of action.
• ? Synergistic effects with radiation and docetaxel were explored using colony‐forming and MTT assays.

RESULTS

• ? At concentrations of 15µM, BiQ2, BiQ3, BiQ11, BiQ12, and BiQ15 demonstrated cytotoxicity in all prostate cancer cell lines.
• ? Treatment with BiQs limited the ability of prostate cancer cells to form colonies in clonogenic assays.
• ? Exposure of prostate cancer to BiQs increased cellular reactive oxygen species (ROS), decreased ATP production, and promoted apoptosis.
• ? BiQ cytotoxicity was independent of NADP(H):quinone oxidoreductase 1 (NQO1) activity in PrECs, PC‐3 and 22RV1, but not DU‐145 cells.
• ? Exposure of prostate cancer cells to radiation before treatment with BiQs increased their activity allowing for inhibitory effects well below the IC₅₀s of these compounds in PrECs.
• ? Co‐administration of BiQs with docetaxel had minimal additive effects.

CONCLUSIONS

• ? Dimeric naphthoquinones represent a new class of compounds with prostate cancer cytotoxicity and synergistic effects with radiation. The cytotoxic effect of these agents is probably contributed to by the accumulation of ROS and mitochondrial dysfunction.
• ? Further studies are warranted to better characterize this class of potential chemo‐therapeutics.

     

Principles and applications of diffusion-weighted imaging in cancer detection, staging, and treatment follow-up

Diffusion-weighted imaging relies on the detection of the random microscopic motion of free water molecules known as Brownian movement. With the development of new magnetic resonance (MR) imaging technologies and stronger diffusion gradients, recent applications of diffusion-weighted imaging in whole-body imaging have attracted considerable attention, especially in the field of oncology. Diffusion-weighted imaging is being established as a pivotal aspect of MR imaging in the evaluation of specific organs, including the breast, liver, kidney, and those in the pelvis. When used in conjunction with apparent diffusion coefficient mapping, diffusion-weighted imaging provides information about the functional environment of water in tissues, thereby augmenting the morphologic information provided by conventional MR imaging. Detected changes include shifts of water from extracellular to intracellular spaces, restriction of cellular membrane permeability, increased cellular density, and disruption of cellular membrane depolarization. These findings are commonly associated with malignancies; therefore, diffusion-weighted imaging has many applications in oncologic imaging and can aid in tumor detection and characterization and in the prediction and assessment of response to therapy.