Texture Feature Ratios from Relative CBV Maps of Perfusion MRI Are Associated with Patient Survival in Glioblastoma

BACKGROUND AND PURPOSE

Texture analysis has been applied to medical images to assist in tumor tissue classification and characterization. In this study, we obtained textural features from parametric (relative CBV) maps of dynamic susceptibility contrast-enhanced MR images in glioblastoma and assessed their relationship with patient survival.

MATERIALS AND METHODS

MR perfusion data of 24 patients with glioblastoma from The Cancer Genome Atlas were analyzed in this study. One- and 2D texture feature ratios and kinetic textural features based on relative CBV values in the contrast-enhancing and nonenhancing lesions of the tumor were obtained. Receiver operating characteristic, Kaplan-Meier, and multivariate Cox proportional hazards regression analyses were used to assess the relationship between texture feature ratios and overall survival.

RESULTS

Several feature ratios are capable of stratifying survival in a statistically significant manner. These feature ratios correspond to homogeneity (P = .008, based on the log-rank test), angular second moment (P = .003), inverse difference moment (P = .013), and entropy (P = .008). Multivariate Cox proportional hazards regression analysis showed that homogeneity, angular second moment, inverse difference moment, and entropy from the contrast-enhancing lesion were significantly associated with overall survival. For the nonenhancing lesion, skewness and variance ratios of relative CBV texture were associated with overall survival in a statistically significant manner. For the kinetic texture analysis, the Haralick correlation feature showed a P value close to .05.

CONCLUSIONS

Our study revealed that texture feature ratios from contrast-enhancing and nonenhancing lesions and kinetic texture analysis obtained from perfusion parametric maps provide useful information for predicting survival in patients with glioblastoma.

Prostate-specific membrane antigen as a target for cancer imaging and therapy

The prostate-specific membrane antigen (PSMA) is a molecular target whose use has resulted in some of the most productive work toward imaging and treating prostate cancer over the past two decades. A wide variety of imaging agents extending from intact antibodies to low-molecular-weight compounds permeate the literature. In parallel there is a rapidly expanding pool of antibody-drug conjugates, radiopharmaceutical therapeutics, small-molecule drug conjugates, theranostics and nanomedicines targeting PSMA. Such productivity is motivated by the abundant expression of PSMA on the surface of prostate cancer cells and within the neovasculature of other solid tumors, with limited expression in most normal tissues. Animating the field is a variety of small-molecule scaffolds upon which the radionuclides, drugs, MR-detectable species and nanoparticles can be placed with relative ease. Among those, the urea-based agents have been most extensively leveraged, with expanding clinical use for detection and more recently for radiopharmaceutical therapy of prostate cancer, with surprisingly little toxicity. PSMA imaging of other cancers is also appearing in the clinical literature, and may overtake FDG for certain indications. Targeting PSMA may provide a viable alternative or first-line approach to managing prostate and other cancers.

Fluoride content and labelling of toothpastes marketed in India

OBJECTIVE

To enumerate the fluoride content and labelling practices of toothpastes marketed in India and to determine if the content is in accordance with the information provided on the packaging.

METHOD

In vitro analysis of total and free available fluoride in 5 adult and 5 children's fluoride toothpastes in India using fluoride ion electrode. Information on the tube and carton was checked to assess the labelling.

RESULTS

The mean Total Fluoride concentrations (TF) in the toothpastes labelled 1,000 ppm, 500ppm and 458 ppm were 1,000, 500 and 449mg/L (sd values 3, 5 and 4mg/L) respectively. The toothpastes' Total Soluble Fluoride (TSF) concentration was generally slightly less than the TF concentration. Overall mean percentage of TSF concentration was 94% sd 9%. The mean percentage of TSF concentration in SMFP (sodium monofluorophosphate)/CaCO3 (calcium carbonate) containing toothpastes was 86% sd 16% while that in NaF (sodium fluoride)/Si (silica) based toothpastes was 98% sd 1% and 95% sd 1% in the remaining toothpastes with unknown abrasive. NaF/Si based toothpastes had more TSF concentration than the others (p<0.05). All the information required by the Indian regulations was shown on all 10 toothpastes.

CONCLUSION

The available fluoride content of one of the ten toothpastes was substantially less than the total fluoride content. Although the toothpastes were labelled following the guidelines of the regulatory body of India, 3 of the 10 failed to mention the abrasive present.

Comparative Evaluation of Effect of Chlorhexidine and Sodium Fluoride Mouthwashes on Plaque

BACKGROUND

Dental plaque, deposition of microorganisms embedded in extracellular matrix, initiates dental caries and periodontal diseases Thus, removal of dental plaque by mechanical or chemical means is the key intervention in prevention of dental caries and gingivitis.

METHODS

To compare the efficacy of chlorhexidine (0.2%) and sodium fluoride (0.05%) mouthwashes in reduction of plaque deposition, 75 children of age group 8-14 years were divided in three equal groups. Group A and group B were test groups for chlorhexidine and sodium fluoride respectively and group C was control group. The subjects were instructed to rinse the mouth with 10 ml of mouthwash for one minute twice daily for fifteen days. Amount of plaque was analyzed by Silness and Loe index at the beginning and end of the study period. Inter group and intra group comparisons were done to evaluate the efficacy of mouthwashes by using paired t test and Anova test.

RESULTS

There was significant reduction in plaque in both test groups (p= 0.000) whereas in control group, there was no significant reduction in amount of plaque (p=0.100) count. Efficacy of the both mouthwashes was statistically equal.

CONCLUSIONS

Sodium fluoride is as potent antimicrobial agent as chlorhexidine and would be better mouthwash due to its additional remineralization property for prevention of dental caries and gingivitis in children.

Congenital nasal pyriform aperture stenosis: a rare cause of neonatal nasal airway obstruction

Congenital nasal pyriform aperture stenosis (CNPAS) is a rare cause of nasal airway obstruction that clinically mimics choanal atresia in a neonate. The differentiation between the two is very important as the management of the two conditions is different. Timely recognition is important to prevent fatal outcome. CNPAS may present as an isolated condition or with associated craniofacial anomalies. Despite typical findings of CNPAS being present on cross-sectional imaging, this condition is commonly overlooked, probably because of a lack of familiarity with the normal morphological features of the nasal cavity in infants and also owing to a lack of awareness of this rare entity. Here we report a case of CNPAS with pre- and post-surgical CT images and the complication that occurred owing to nasal stenting.

Computational prediction of MHC class I epitopes for most common viral diseases in cattle (Bos taurus)

Viral diseases like foot-and-mouth disease (FMD), calf scour (CS), bovine viral diarrhea (BVD), infectious bovine rhinotracheitis (IBR) etc. affect the growth and milk production of cattle (Bos taurus) causing severe economic loss. Epitope-based vaccine designing have been evolved to provide a new strategy for therapeutic application of pathogen-specific immunity in animals. Therefore, identification of major histocompatibility complex (MHC) binding peptides as potential T-cell epitopes is widely applied in peptide vaccine designing and immunotherapy. In this study, MetaMHCI tool was used with seven different algorithms to predict the potential T-cell epitopes for FMD, BVD, IBR and CS in cattle. A total of 54 protein sequences were filtered out from a total set of 6351 sequences of the pathogens causing the said diseases using bioinformatics approaches. These selected protein sequences were used as the key inputs for MetaMHCI tool to predict the epitopes for the BoLA-All MHC class I allele of B. taurus. Further, the epitopes were ranked based on a proposed principal component analysis based epitope score (PbES). The best epitope for each disease based on its predictability through maximum number of predictors and low PbES was modeled in PEP-FOLD server and docked with the BoLA-A11 protein for understanding the MHC-epitope interaction. Finally, a total of 78 epitopes were predicted, out of which 27 were for FMD, 25 for BVD, 12 for CS and 14 for IBR. These epitopes could be artificially synthesized and recommended to vaccinate the cattle for the considered diseases. Besides, the methodology adapted here could also be used to predict and analyze the epitopes for other microbial diseases of important animal species.

High cortisol response to adrenocorticotrophic hormone identifies ewes with reduced melanocortin signalling and increased propensity to obesity

We have identified female sheep that have either high (HR) or low (LR) cortisol responses to adrenocorticotrophin. On a high-energy diet, HR have greater propensity to weight gain and obesity, although the underlying mechanisms remain to be determined. Hypothalamic appetite-regulating peptides (ARP) exert reciprocal effects on food intake and energy expenditure. We aimed to quantify the expression and function of ARP in LR and HR ewes (n = 4 per group). Gene expression for neuropeptide Y (NPY), agouti-related peptide (AgRP) pro-opiomelanocortin (POMC), melanin-concentrating hormone (MCH), orexin and the melanocortin receptors (MC3R and MC4R) was measured by in situ hybridisation. Expression of NPY, AgRP and POMC was similar in HR and LR, although expression of orexin, MCH, MC3R and MC4R was higher (P < 0.05) in LR. Intracerebroventricular infusions of a low dose (50 μg/h) of NPY, α-melanocyte-stimulating hormone (αMSH), orexin and MCH were performed between 10.00 h and 16.00 h in meal-fed ewes (n = 6-7 per group). Skeletal muscle and retroperitoneal (RP) fat temperatures were recorded using dataloggers. Post-prandial thermogenesis in muscle was higher (P < 0.05) in LR. There was little effect of ARP infusion on muscle or fat temperature in either group. Infusion of these doses of NPY, MCH or orexin did not stimulate food intake in meal-fed ewes, although αMSH reduced (P < 0.01) food intake in LR only. Using 24-h ARP infusions with ad lib. feeding, NPY increased (P < 0.001) food intake in both groups but αMSH was only effective in LR (P < 0.05). In summary, we show that HR are resistant to the satiety effects of αMSH and this coincides with a reduced expression of both the MC3R and MC4R in the paraventricular nucleus of the hypothalamus. We conclude that an increased propensity to obesity in HR female sheep is associated with reduced melanocortin signalling.

Calcium carbonate crystallization in tailored constrained environments

This research shows that by tailoring the assembly of lecithin molecules it is possible to modulate the texture, polymorphism, size and shape of calcium carbonate crystals.