Efficacy of high intensity diode laser as an adjunct to non-surgical periodontal treatment: a randomized controlled trial

The high intensity diode laser has been studied in periodontics for the reduction of subgingival bacteria in non-surgical treatment. Our study evaluated the bacterial effect as well as changes in periodontal clinical parameters promoted by root scaling and planing associated with this wavelength. Twenty-seven patients randomly assigned in two groups underwent root scaling and planing on the tested sites, and only the experimental group received the diode laser irradiation. Among the clinical parameters studied, the clinical probing depth (CPD) and the clinical attachment level (CAL) resulted in significant enhancement in the control group when compared with the experimental group (P = 0.014 and P = 0.039, respectively). The results were similar for both groups regarding the plaque index (PI) and bleeding on probing (BP). No significant difference in the microbiological parameters was observed between the control and experimental groups. It was possible to conclude that the high power diode laser adjunct to the non-surgical periodontal treatment did not promote additional effects to the conventional periodontal treatment.

Evaluation of laccases and melanization in clinical and environmental Cryptococcus neoformans samples by non-denaturing PAGE

The increased incidence of infections caused by the opportunistic pathogen Cryptococcus neoformans, which mainly affects immunocompromised patients but can also infect immunocompetent individuals, has needed additional studies on this micro-organism`s pathogenicity and factors related to virulence, such as enzyme production, for a better understanding of the aetiology of cryptococcosis. The aim of this study was to verify the applicability of non-denaturing PAGE for analysis of laccases by quantification of the amount of melanin pigment produced by clinical and environmental strains of C. neoformans. After incubation of the gel with the substrate L-dopa, strains produced melanin spots of a bright brown to black colour. Quantification of these spots was performed by densitometry analysis and the amount of melanin produced was calculated and compared among the strains. All strains showed laccase activity. Serotype B strains showed a higher melanin intensity than serotype A strains. Over half of the clinical strains (56.2%) showed the lowest melanin intensities, suggesting that melanin production may not be the main virulence factor against host defence. The clinical strain ICB 88 revealed two melanin spots on the gel, indicating the presence of two laccase isoforms. The environmental strains showed the highest values of melanin intensity, which may be related to previous exposure to environmental stress conditions.

A non-parametric vessel detection method for complex vascular structures

Modern medical imaging techniques enable the acquisition of in vivo high resolution images of the vascular system. Most common methods for the detection of vessels in these images, such as multiscale Hessian-based operators and matched filters, rely on the assumption that at each voxel there is a single cylinder. Such an assumption is clearly violated at the multitude of branching points that are easily observed in all, but the Most focused vascular image studies. In this paper, we propose a novel method for detecting vessels in medical images that relaxes this single cylinder assumption. We directly exploit local neighborhood intensities and extract characteristics of the local intensity profile (in a spherical polar coordinate system) which we term as the polar neighborhood intensity profile. We present a new method to capture the common properties shared by polar neighborhood intensity profiles for all the types of vascular points belonging to the vascular system. The new method enables us to detect vessels even near complex extreme points, including branching points. Our method demonstrates improved performance over standard methods on both 2D synthetic images and 3D animal and clinical vascular images, particularly close to vessel branching regions. (C) 2008 Elsevier B.V. All rights reserved.