Vaccine effect using a live attenuated nef-deficient simian immunodeficiency virus of African green monkeys in the absence of detectable vaccine virus replication in vivo

Immunization of adult macaques with live attenuated simian immunodeficiency viruses (SIVs) lacking the nef genes has been shown to protect against challenge with full-length pathogenic SIV. To test live attenuated virus vaccines for the first time in a natural host we have constructed a mutant SIV from African green monkeys (SIVagm) with a deletion of 125 bp in the nef gene (SIVagm3Δnef). This mutant showed moderately delayed in vitro replication in the T cell line MOLT-4/8 and in primary peripheral blood mononuclear cells from African green monkeys (Cercopithecus aetiops) and pig-tailed macaques (Macaca nemestrina) compared with cloned wild-type SIVagm3. In contrast, in vivo replication of SIVagm3Δnef in African green monkeys was severely impaired or undetectable and did not induce seroconversion. After challenge with wild-type SIVagm3 the SIVagm3Δnef preinoculated African green monkeys showed a memory antibody response that declined after week 2. In three of four African green monkeys the cell-associated virus load and in two of four African green monkeys the plasma virus load was dramatically decreased after the challenge compared with naive control animals. The remaining animal showed no evidence of productive challenge virus replication. This study demonstrates that a strong vaccine effect or protection in the SIVagm/African green monkey system is possible using a live attenuated vaccine in the absence of a productive infection and corresponding humoral immune response.     

Identification of Candida species in the clinical laboratory: a review of conventional,commercial, and molecular techniques

In healthy individuals, Candida species are considered commensal yeasts of the oral cavity. However, these microorganisms can also act as opportunist pathogens, particularly the so‐called non‐albicans Candida species that are increasingly recognized as important agents of human infection. Several surveys have documented increased rates of C. glabrata, C. tropicalis, C. guilliermondii, C. dubliniensis, C. parapsilosis, and C. krusei in local and systemic fungal infections. Some of these species are resistant to antifungal agents. Consequently, rapid and correct identification of species can play an important role in the management of candidiasis. Conventional methods for identification of Candida species are based on morphological and physiological attributes. However, accurate identification of all isolates from clinical samples is often complex and time‐consuming. Hence, several manual and automated rapid commercial systems for identifying these organisms have been developed, some of which may have significant sensitivity issues. To overcome these limitations, newer molecular typing techniques have been developed that allow accurate and rapid identification of Candida species. This study reviewed the current state of identification methods for yeasts, particularly Candida species.     

The influence of epigenetics in relation to oral health

The immune response is influenced by genetic and epigenetic factors, as well as disease and environmental factors. The term ‘epigenetics’ describes changes in the genome that influence the gene expression without altering the DNA sequence. In contrast to genetic changes in the DNA, epigenetic changes are reversible and are influenced by environmental factors. The aim of this study is to review the literature on epigenetic modifications with respect to oral health and inflammatory conditions in the oral cavity and to discuss the potential use of this new research field for the dental hygienists' and/or dentists' clinical work. Relevant publications were identified using the PubMed database without limits. The searches were conducted during January to March 2012 and resulted in articles published between 1912 and 2012. Key factors such as environment, diet, smoking, bacteria and inflammation were identified to be relevant to oral health. The result of this review article shows that there is a void in the research on epigenetics in relation to oral health. Identification of epigenetic modifications correlating with oral health may not only present a link between the influence of genetics and that of the environment on oral diseases but also provide new treatment models and tools for the dental professionals.     

Olfactory Bulb D2/D3 Receptor Availability after Intrastriatal Botulinum Neurotoxin-A Injection in a Unilateral 6-OHDA Rat Model of Parkinson’s Disease

Olfactory deficits occur as early non-motor symptoms of idiopathic Parkinson’s disease (PD) in humans. The first central relay of the olfactory pathway, the olfactory bulb (OB), depends, among other things, on an intact, functional crosstalk between dopaminergic interneurons and dopamine receptors (D₂/D₃R). In rats, hemiparkinsonism (hemi-PD) can be induced by unilateral injection of 6-hydroxydopamine (6-OHDA) into the medial forebrain bundle (MFB), disrupting dopaminergic neurons of the substantia nigra pars compacta (SNpc). In a previous study, we showed that subsequent injection of botulinum neurotoxin-A (BoNT-A) into the striatum can reverse most of the pathological motor symptoms and normalize the D₂/D₃R availability. To determine whether this rat model is suitable to explain olfactory deficits that occur in humans with PD, we examined the availability of D₂/D₃R by longitudinal [¹⁸F]fallypride-PET/CT, the density of tyrosine hydroxylase immunoreactivity in the OB, olfactory performance by an orienting odor identification test adapted for rats, and a connectome analysis. PET/CT and immunohistochemical data remained largely unchanged after 6-OHDA lesion in experimental animals, suggesting that outcomes of the 6-OHDA hemi-PD rat model do not completely explain olfactory deficits in humans. However, after subsequent ipsilateral BoNT-A injection into the striatum, a significant 8.5% increase of the D₂/D₃R availability in the ipsilateral OB and concomitant improvement of olfactory performance were detectable. Based on tract-tracing meta-analysis, we speculate that this may be due to indirect connections between the striatum and the OB.     

Effects of body image on dieting,exercise, and anabolic steroid use in adolescent males

This cross-sectional survey study examined body image, dieting and exercise variables, and steroid use in 2,088 high-school graduates aged 18 years. In contrast to women, more men wished to gain (46%) rather than lose weight (32%). Men who wished to gain weight were more satisfied with their body shape, showed no fear of fatness, and dieted and exercised less frequently than did men who wished to lose weight. The prevalence of dieting was low (4%), even among men who wished to lose weight (9%), and physical exercise was more likely to be used for both weight loss and weight gain. Contrary to expectations, anabolic steroid use was rare (0.6%) and was not associated with a desire for weight gain. Steroid users were more likely to engage in running and swimming than football. The data did not support the notion that anabolic steroid use is widespread among high-school males. © 1995 by John Wiley & Sons, Inc.     

Body weight and dieting in adolescence: Impact of socioeconomic status

This cross-sectional survey study examined dieting and exercise variables as a function of parental education in 2,174 male and 1,804 female college-bound high school graduates aged 18 years. Parental education is an index of socioeconomic status (SES). Higher SES was associated with lower current and desired body weight in both women and men. The prevalence of dieting, binging, and vigorous exercise for weight control increased with SES for women but not for men. These data confirm the inverse relationship between body weight, dieting, and social class, previously demonstrated with American adults. © 1994 by John Wiley & Sons, Inc.     

Magnetic resonance identified ventricular dilation in traumatic brain injury: comparison of pre- and postin jury scan and postin jury results.

A case study is presented in which a patient received magnetic resonance (MR) imaging of the brain 3 months prior to a severe traumatic brain injury (TBI). The post-TBI MR findings are compared and contrasted with the pre-TBI MR images. The posttraumatic changes demonstrate a significant dilation of the ventricular system which reflects diffuse axonal injury and loss of brain substance. Correspondingly, the neuropsychological studies in this individual reflect global deficits which match the nonspecific, traumatically induced degenerative changes found in the postinjury MR scan. This case study is unique in that specific preinjury MR findings are available for direct comparison and quantitative analysis of TBI-associated changes in brain structure with neuropsychological outcome.