Progress in understanding oral health and HIV/AIDS

Over the last 30 years, there have been significant advances in our scientific knowledge of HIV disease, including prevention, detection, medical management, and attempts at cure. Investigations and observations of the oral cavity in individuals with HIV disease have contributed substantially to scientific discovery and innovation. Challenges remain for managing existing and emerging oral diseases associated with HIV and understanding the contribution of latent oral mucosal reservoirs to HIV eradication.     

Regional neural dysfunctions in chronic schizophrenia studied with positron emission tomography

OBJECTIVE: Whether chronicity of illness produces progressive neural abnormality is an important question in current schizophrenia research. Positron emission tomography (PET) offers an opportunity to visualize and measure blood flow in vivo to address this issue. The authors previously compared healthy volunteers with neuroleptic-naive patients experiencing their first episode of schizophrenia and reported that abnormalities in blood flow, including lower flow in prefrontal regions and higher flow in the thalamus and cerebellum, are present at the early stage of schizophrenic illness. The goal of the present study was to measure blood flow with PET in patients with chronic schizophrenia. METHOD: PET was used to examine regional cerebral blood flow (rCBF) in 30 patients with chronic schizophrenia and 30 normal comparison subjects. To determine if the patterns of flow abnormality in the patients with chronic schizophrenia were similar to those of patients experiencing their first episode of schizophrenia, the same cognitive condition was examined as in the earlier study. The patients with chronic schizophrenia in the current study had been neuroleptic-free for at least 3 weeks. RESULTS: As in the authors' previous study, the chronically ill patients showed lower flow in prefrontal areas and higher flow in thalamic and cerebellar regions than normal comparison subjects, suggesting that a similar neural dysfunction occurs in both first-episode and chronic schizophrenia. CONCLUSIONS: rCBF abnormalities in patients with chronic schizophrenia are not due to chronicity of illness or the effects of medication. These results provide evidence that the primary neural abnormalities in schizophrenia may occur in cortical, cerebellar, and thalamic regions and that the dysfunction in these regions may explain the "loosening of associations" that Bleuler considered to be the fundamental cognitive phenotype of schizophrenia. These abnormalities can be reconceptualized as "cognitive dysmetria."     

Predictors of adult height and weight in boys treated with methylphenidate for childhood behavior problems

OBJECTIVE: To examine associations between childhood treatment with methylphenidate (MPH) and adult height and weight. METHOD: Subjects were 97 boys, aged 4 to 12 years, with behavior problems who were (1) referred to a child psychiatry outpatient clinic, (2) treated clinically with MPH for an average of 36 months, and (3) reevaluated between ages 21 and 23 years. Hierarchical analyses predicted adult height and weight from sets of non-medication and medication-related variables. RESULTS: Medicated subjects' age, height, and parental socioeconomic status (SES) at referral predicted 44.8% of variation in adult height. Medicated subjects' birth weight, age, height and weight at referral, and parental SES predicted 61.8% of variation in adult weight. With these non-medication variables held constant, initial nausea and vomiting side effects predicted 4.4% incremental variation in adult height, and MPH maintenance dose predicted 3.2% incremental variation in adult weight. CONCLUSIONS: Medicated individuals who had attained their final stature did not differ in average height or weight from family, community, or unmedicated controls. Most aspects of medication were not associated with adult height or weight. In some individuals, nausea and vomiting side effects and treatment with higher doses of MPH were associated with adult growth decrements.     

A new technique for pet slice orientation and MRI-PET coregistration

We report and validate a technique for magnetic resonace imaging (MRI) positron emission tomography (PET) coregistration and the optimization of PET slice orientation that enhances and complements existing techniques. The technique depends on an external fiducial system and on software that models the relationship of the PET gantry with respect to a three-dimensional (3D) MR reconstruction of each subject's brain anatomy. The technique offers the possibility of using individual neuroanatomical information to plan PET activation studies. Estimated 3D errors average 3 mm in [¹⁵O]H₂O PET activation studies. In-plane interinjection movement averages less than 1 mm. The resulting MRI-PET coregistration provides a basis for bringing neuroanatomical information to bear on a number of issues critical for the interpretation of functional imaging studies. © 1995 Wiley-Liss, Inc.     

Cryopreservation of all prezygotes in patients at risk of severe hyperstimulation does not eliminate the syndrome, but the chances of pregnancy are excellent with subsequent frozen-thaw transfers

In-vitro fertilization patients (n = 15) at risk of ovarian hyperstimulation syndrome (OHSS) (oestradiol > or =4500 pg/ml on the day of human chorionic gonadotrophin administration and 25 or more follicles of intermediate or large size) underwent aspiration of all follicles and cryopreservation of all fertilized oocytes at the pronuclear stage. Patients were monitored for up to 2 weeks post- retrieval. Subsequent transfer of cryopreserved-thawed embryos was performed in programmed cycles using exogenous oestrogen and progesterone for endometrial preparation. Two patients (13%) developed OHSS necessitating hospitalization and vaginal aspiration of ascitic fluid. Two other patients (13%) developed moderate OHSS requiring ascitic fluid vaginal aspiration in the office setting, with dramatic improvement of the condition. Subsequent transfer of cryopreserved- thawed embryos yielded a clinical pregnancy rate of 58% per transfer and ongoing or delivery rates of 42 and 67% per transfer and per patient respectively. By eliminating pregnancy potential with cryopreservation of all prezygotes and examining the pregnancy potential with subsequent cryopreserved-thawed transfers, it is concluded that OHSS is reduced, but not eliminated for patients at risk. Subsequent transfer of cryopreserved-thawed prezygotes in a programmed cycle with exogenous steroids yields an excellent pregnancy rate.      

Interchromosomal duplications of the adrenoleukodystrophy locus: a phenomenon of pericentromeric plasticity

A 9.7 kb segment encompassing exons 7-10 of the adrenoleukodystrophy (ALD) locus of the X chromosome has duplicated to specific locations near the pericentromeric regions of human chromosomes 2p11,10p11, 16p11 and 22q11. Comparative sequence analysis reveals 92-96% nucleotide identity, indicating that the autosomal ALD paralogs arose relatively recently during the course of higher primate evolution (5-10 million years ago). Analysis of sequences flanking the duplication region identifies the presence of an unusual GCTTTTTGC repeat which may be a sequence-specific integration site for the process of pericentromeric- directed transposition. The breakpoint sequence and phylogenetic analysis predict a two-step transposition model, in which a duplication from Xq28 to pericentromeric 2p11 occurred once, followed by a rapid distribution of a larger duplicon cassette among the pericentromeric regions. In addition to facilitating more effective mutation detection among ALD patients, these findings provide further insight into the molecular basis underlying a pericentromeric-directed mechanism for non- homologous interchromosomal exchange.      

Urban legends series: oral manifestations of HIV infection

Human immunodeficiency virus‐related oral lesions (HIV‐OLs), such as oral candidiasis (OC) and oral hairy leukoplakia (OHL), have been recognized as indicators of immune suppression since the beginning of the global HIV epidemic. The diagnosis and management of HIV disease and spectrum of opportunistic infection has changed over the past 30 years as our understanding of the infection has evolved. We investigated the following controversial topics: (i) Are oral manifestations of HIV still relevant after the introduction of highly active antiretroviral therapy (HAART)? (ii) Can we nowadays still diagnose HIV infection through oral lesions? (iii) Is the actual classification of oral manifestations of HIV adequate or does it need to be reviewed and updated? (iv) Is there any novelty in the treatment of oral manifestations of HIV infection? Results from extensive literature review suggested the following: (i) While HAART has resulted in significant reductions in HIV‐OLs, many are still seen in patients with HIV infection, with OC remaining the most common lesion. While the relationship between oral warts and the immune reconstitution inflammatory syndrome is less clear, the malignant potential of oral human papillomavirus infection is gaining increasing attention. (ii) Effective antiretroviral therapy has transformed HIV from a fatal illness to a chronic manageable condition and as a result expanded screening policies for HIV are being advocated both in developed and in developing countries. Affordable, reliable, and easy‐to‐use diagnostic techniques have been recently introduced likely restricting the importance of HIV‐OLs in diagnosis. (iii) The 1993 EC‐Clearinghouse classification of HIV‐OLs is still globally used despite controversy on the relevance of periodontal diseases today. HIV‐OL case definitions were updated in 2009 to facilitate the accuracy of HIV‐OL diagnoses by non‐dental healthcare workers in large‐scale epidemiologic studies and clinical trials. (iv) Research over the last 6 years on novel modalities for the treatment of HIV‐OLs has been reported for OC and OHL.     

MR imaging of the scrotum: normal anatomy

High-resolution magnetic resonance (MR) imaging with a surface coil was utilized to evaluate the normal scrotum. Scrotal contents, spermatic canal, and inguinal regions were visualized within the same field of view. Differences in signal intensity in the testis, epididymis, tunica albuginea, fluid, fat, and spermatic cord allowed for clear delineation of these structures in detail. The high contrast and spatial resolution of MR imaging, coupled with the wide field of view and absence of ionizing radiation, make MR imaging well suited for evaluation of the scrotum.     

Emotional blunting following left basal ganglia stroke: The role of depression and fronto-limbic functional alterations

Disorders of the basal ganglia (BG) alter perception and experience of emotions. Left hemisphere BG (LBG) stroke is also associated with depression. The interplay between depression and alterations in emotional processing following LBG stroke was examined. Evoked affective responses to emotion-laden pictorial stimuli were compared among LBG stroke and healthy participants and participants with stroke damage in brain regions not including the LBG selected to equate depression severity (measured using the Hamilton Depression Scale) with LBG damage participants. Brain activity {[O¹⁵]water positron emission tomography, PET} was measured in LBG stroke relative to healthy participants to identify changes in regions associated with emotion processing and depression. LBG stroke subjects reported less intense emotions compared with healthy, but not stroke comparison participants. Depression negatively correlated with emotional experience for positive and negative emotions. In response to positive stimuli, LBG subjects exhibited higher activity in amygdala, anterior cingulate, dorsal prefrontal cortex, and insula compared to healthy volunteers. In response to negative stimuli, LBG subjects demonstrated lower activity in right frontal-polar region and fusiform gyrus. Higher baseline activity in amygdala and ventral and mesial prefrontal cortex and lower activity in left dorsal lateral prefrontal cortex were associated with higher depression scores. LBG stroke led to blunted emotions, and brain activity alterations accounting for reduced affective experience, awareness and depression. Depression and fronto-limbic activity changes may contribute to emotional blunting following LBG stroke.