Clinical feasibility of mandibular implant overdenture retainers submitted to immediate load

Gerodontology 2010; doi: 10.1111/j.1741‐2358.2010.00374.x
Clinical feasibility of mandibular implant overdenture retainers submitted to immediate load Introduction: Millions of people around the world do not have access to the benefits of osseointegration. Treatments involving oral rehabilitation with overdentures have been widely used by specialists in the oral medicine field. This is an alternative therapy for retention and stability achievement in total prosthesis with conventional treatment, and two implants are enough to establish a satisfactory overdenture. Objective: The objectives of the study were to evaluate 16 patients of both sexes, with an average age of 47.4 ± 4 years, using electromyographic analysis of masseter and temporal muscles and analyse the increase of incisive and molar maximal bite force with their existing complete dentures and following mandibular implant overdenture therapy to assess the benefits of this treatment. Materials and methods: For these tests, the Myosystem‐BR1 electromyograph and the IDDK Kratos dynamometer were used. Statistical analysis was performed using the repeated measures test (SPSS 17.0). Results: A decrease in electromyographic activity during the rest, lateral and protrusion movements and increase of the maximal incisive and molar bite force after 15 months with a mandibular implant overdenture was observed. Conclusion: All the patients in this study reported a considerable improvement in the masticatory function and prostheses stability following treatment. It is possible to propose that the use of mandibular implants overdenture should become the selected treatment for totally edentulous patients to facilitate oral function and quality of life.     

Reversible lysozyme immobilization onto N,N′-bis-(3-(4-morpholino)-propyl)-3,4,9,10-perylenetetracarboxylic acid dimide (MPPDI) attached polymeric nanospheres

Novel hydrophobic nanospheres with an average size of 200 nm utilizing N,N′-bis-(3-(4-morpholino)-propyl)-3,4,9,10-perylenetetracarboxylic acid dimide (MPPDI) as a monomer were prepared by surfactant free emulsion polymerization of 2-hydroxyethyl methacrylate (HEMA) and MPPDI conducted in an aqueous dispersion medium. The nanospheres were used for the adsorption of lysozyme. The system parameters, such as effect of the adsorption conditions (i.e. enzyme concentration, medium pH, and temperature) and the reusability of the support were studied. Specific surface area of the nonporous nanospheres was found 664 m²/g. Poly(HEMA–MPPDI) nanospheres were characterized by Fourier transform infrared spectroscopy (FT-IR), elemental analysis and scanning electron microscopy (SEM). Then, poly(HEMA–MPPDI) nanospheres were used in the adsorption of lysozyme in batch system. Using an optimized adsorption protocol, 400 mg lysozyme/g nanosphere loading capacity was obtained. The adsorption phenomena appeared to follow a typical Langmuir isotherm. Lysozyme could be repeatedly adsorbed and desorbed with poly(HEMA–MPPDI) nanospheres without noticeable loss in the adsorption capacity.     

Comparison of Methods to Account for Relatedness in Genome-Wide Association Studies with Family-Based Data

Approaches based on linear mixed models (LMMs) have recently gained popularity for modelling population substructure and relatedness in genome-wide association studies. In the last few years, a bewildering variety of different LMM methods/software packages have been developed, but it is not always clear how (or indeed whether) any newly-proposed method differs from previously-proposed implementations. Here we compare the performance of several LMM approaches (and software implementations, including EMMAX, GenABEL, FaST-LMM, Mendel, GEMMA and MMM) via their application to a genome-wide association study of visceral leishmaniasis in 348 Brazilian families comprising 3626 individuals (1972 genotyped). The implementations differ in precise details of methodology implemented and through various user-chosen options such as the method and number of SNPs used to estimate the kinship (relatedness) matrix. We investigate sensitivity to these choices and the success (or otherwise) of the approaches in controlling the overall genome-wide error-rate for both real and simulated phenotypes. We compare the LMM results to those obtained using traditional family-based association tests (based on transmission of alleles within pedigrees) and to alternative approaches implemented in the software packages MQLS, ROADTRIPS and MASTOR. We find strong concordance between the results from different LMM approaches, and all are successful in controlling the genome-wide error rate (except for some approaches when applied naively to longitudinal data with many repeated measures). We also find high correlation between LMMs and alternative approaches (apart from transmission-based approaches when applied to SNPs with small or non-existent effects). We conclude that LMM approaches perform well in comparison to competing approaches. Given their strong concordance, in most applications, the choice of precise LMM implementation cannot be based on power/type I error considerations but must instead be based on considerations such as speed and ease-of-use.     

A histological and ultrastructural investigation of the female reproductive system of the water snake (Erythrolamprus miliaris): Oviductal cycle and sperm storage

We studied the structural and cellular organisation of the oviduct of Erythrolamprus miliaris including its morphological variation during the reproductive cycle using light microscopy, scanning electron microscopy and transmission electron microscopy. Four anatomically distinct regions compose the oviduct of E. miliaris including the anterior and posterior infundibulum, glandular uterus, non-glandular uterus and pouch. The cells of the oviductal epithelium secrete material by apocrine and merocrine processes, which vary between the anatomical regions and according to each phase of the reproductive cycle. The infundibular epithelium secretes electron dense vacuoles, which suggests the production of lipids, whereas the epithelial secretion of the glandular uterus, non-glandular uterus and pouch creates lucent and slightly electron dense vacuoles, indicating the production of glycoproteins. The timing of mating, vitellogenesis and sperm storage directly influences the morphofunctional alterations in the oviducts of E. miliaris. Sperm storage occurs only in the infundibular receptacles with increased production of the neutral carbohydrates in the presence of male gametes. Sperm storage happens in vitellogenic, non-vitellogenic and pregnant females of E. miliaris. Thus, females may be able to produce multiple clutches at different seasons of the year regardless of mating during autumn.     

Characterization of Bacterial Flora from Afşin–Elbistan Lignite Mine for Potential Microbial Biotech Applications

Abstract

The energy demand is enhancing day by day all over the world with the increasing of huge population. Lignite, a fossil fuel with low energy efficiency, is used in many different fields. However, lignite is primarily an energy source and its use without treatment causes environmental pollution as well as low energy efficiency. Advantages are known for the use of microorganisms in lignite processing technologies, and research is underway to improve this process. In this research designed to meet this need, isolation and characterization of bacteria with potential for use in biotechnological applications resistant to extreme conditions were performed from lignite mine. Turkey’s largest lignite mine bacterial flora have been identified for the first time in this study. In addition to lignite processing technologies, a bacterial strain collection has been created to be used in other biotechnological studies. This collection of bacteria includes Methylorubrum zatmanii, Streptomyces argenteolus, Streptomyces galilaeus, Pseudomonas mandelii, Paenarthrobacter aurescens, Paeniglutamicibacter sulfureus, Arthrobacter humicola, Bacillus pumilus, Bacillus subtilis, Bacillus safensis, Kocuria polaris, Arthrobacter sp., Rhodococcus sp. This specific bacteria collection is open to sharing with other researchers who want to do field applications.     

Peptidase activities in the semen from the ductus deferens and uterus of the neotropical rattlesnake Crotalus durissus terrificus

To understand the role of peptidases in seminal physiology of Crotalus durissus terrificus, intra- and inter-seasonal activity levels of acid (APA), basic (APB), puromycin-sensitive (APN-PS) and puromycin-insensitive neutral (APN-PI), cystyl (CAP), dipeptidyl-IV (DPPIV), type-1 pyroglutamyl (PAP-I) and prolyl-imino (PIP) aminopeptidases as well as prolyl endopeptidase (POP) were evaluated in soluble (SF) and/or membrane-bound (MF) fractions of semen collected from the ductus deferens of the male reproductive tract and from the posterior portion of the uterus. Seminal APB, PIP and POP were detected in SF, while other peptidases were detected in SF and MF. Only the convoluted posterior uterus in winter and autumn had semen. Relative to other examined peptidases, in general, APN-PI, APN-PS and APB activities were predominant in the semen from the uterus and throughout the year in the semen from the ductus deferens, suggesting their great relevance in the seminal physiology of C. d. terrificus. The levels of peptidase activities in the ductus deferens semen varied seasonally and were different from those of semen in the uterus, suggesting that their modulatory actions on susceptible peptides are integrated to the male reproductive cycle events and spermatozoa viability of this snake.     

Discontinuous Schedule of Bevacizumab in Colorectal Cancer Induces Accelerated Tumor Growth and Phenotypic Changes

Antiangiogenics administration in colorectal cancer patients seemed promising therapeutic approach. Inspite of early encouraging results, it however gave only modest clinical benefits. When AAG was administered with discontinuous schedule, the disease showed acceleration in certain cases. Though resistance to AAG has been extensively studied, it is not documented for discontinuous schedules. To simulate clinical situations, we subjected a patient-derived CRC subcutaneous xenograft in mice to three different protocols: 1) AAG (bevacizumab) treatment for 30 days (group A) (group B was the control), 2) bevacizumab treatment for 50 days (group C) and bevacizumab for 30 days and 20 without treatment (group D), and 3) bevacizumab treatment for 70 days (group E) and 70 days treatment with a drug-break period between day 30 and 50 (group F). The tumor growth was monitored, and at sacrifice, the vascularity of tumors was measured and the proangiogenic factors quantified. Tumor phenotype was studied by quantifying cancer stem cells. Interrupting bevacizumab during treatment accelerated tumor growth and revascularization. A significant increase of proangiogenic factors was observed when therapy was stopped. On withdrawal of bevacizumab, as also after the drug-break period, the plasmatic VEGF increased significantly. Similarly, a notable increase of CSCs after the withdrawal and drug-break period of bevacizumab was observed (P<.01). The present study indicates that bevacizumab treatment needs to be maintained because discontinuous schedules tend to trigger tumor regrowth, and increase tumor resistance and CSC heterogeneity.