Anxiety and hippocampus volume in the rat.

In depressed patients as well as healthy controls, a positive relationship between hippocampal volume and trait anxiety has been reported. This study sought to explore the possible inter-relation between hippocampal volume and trait anxiety further. Magnetic resonance imaging at 7 T was used to measure hippocampal volumes in a rat model of extremes in trait anxiety (experiment 1) and in a Wistar population with normal anxiety-related behavior (experiment 2). In addition to anxiety-related behavior, potentially confounding factors (depression-like, exploratory, and locomotor behavior) were assessed. Experiment 1 globally supported the hypothesis of a positive relationship between hippocampus volume and trait anxiety but did not allow for ruling out possible confounds arising from cosegregation of other behavioral traits. Experiment 2 yielded strong evidence for a negative relationship which was specific for trait anxiety. Thus, the relationship between hippocampal volume and anxiety may be more complex than expected. Interestingly, anxiety-related behavior in experiment 2 had a stronger influence on hippocampal volume than depression-like behavior. In the light of hippocampal volume loss in anxiety disorder and frequent comorbidity of anxiety and depression, this finding suggests that further research into the relationship between anxiety and hippocampal volume may be critical for understanding hippocampal contributions to normal and pathological behavior.     

Versuche zur Kausalanalyse der retinomotorischen Erscheinungen

Ohne Zusammenfassung     

Volumetric measurements of the brachial and carotid arteries in dialysis grafts: is there evidence of a subclavian-carotid artery steal syndrome?

Dialysis grafts may lead to major hyperperfusion in the graft arm and to hypertrophic, hypervolemic cardiomyopathy. No data have been published concerning the impact of dialysis grafts on the cerebral perfusion in relation to a potential carotid steal syndrome, possibly causing neurologic or neuropsychologic symptoms. In 30 patients (32 to 74 years old) with dialysis grafts we studied the following hemodynamic parameters in the brachial and common carotid arteries bilaterally: Flow velocities (spectral Doppler sonography), diameter (B-mode) and volume flow (color M-mode) with a color duplex system (Philips P700). Volume flow in the brachial arteries of the graft arm averaged 1032 ml/min (range, 158 to 2854 ml/min) as compared to 42 ml/min (range, 15 to 108 ml/min) in the nongraft arm. Almost identical volume flow data could be seen in both common carotid arteries (418 versus 421 ml/min) with no evidence of reduced flow in the carotid arteries in patients with high flow in the graft arm. A tendency toward higher volume flow in both carotid arteries in patients with high volume flow in the graft arm was noted. We found no evidence of shunt-induced cerebral hypoperfusion. Cerebral autoregulation appears to be patent even with high brachial artery shunt volume.     

Developing a workable infection control policy for the dental laboratory

An enforced infection control policy in a laboratory will reduce occupational exposure to blood-borne pathogens and other infectious diseases and protect the dental laboratory personnel from exposure to infective disease. An outline of a workable laboratory infection control policy based on "Occupational Exposure to Bloodborne Pathogens" requirements is presented.     

Lung injury induced by antibody fragments to angiotensin-converting enzyme.

Rabbits given goat anti-rabbit angiotensin-converting enzyme antibodies or derived antibody fragments develop rapidly fatal pulmonary edema. Endothelial cell injury is manifested by bleb formation and the disintegration of cell membranes. Platelets are found along the injured endothelium and leukocytes block capillary lumens. The pathologic features are similar when immune IgG, F(ab')2, or Fab are given. In vitro studies of complement activation show that solubilized, purified angiotensin-converting enzyme alone activates C1, with consumption of C4 and C3. Addition of immune IgG plus converting enzyme enhances this activation. F(ab')2 plus enzyme enhances only C3 consumption, while Fab with enzyme produces no additional complement utilization. Thus, while complement activation may be involved in the pathogenesis of injury induced by IgG or F(ab')2, the mechanism of Fab-induced endothelial injury remains unclear.     

Fatal desquamative interstitial pneumonia in an infant: case report with transmission and scanning electron microscopical studies

Desquamative interstitial pneumonia in a young infant followed a rapidly fatal course and developed morphologic features of honey-combing, giant cell pneumonia, and pulmonary alveolar proteinosis. The rapid and fatal progression of the disease in spite of steroid therapy and the polymorphous histologic appearance of the lungs at autopsy raise doubt that the disease is a relatively benign and uniform entity and invalidate the classical initial histologic features as prognostic indicators.     

High vs low anxiety-related behavior rats: an animal model of extremes in trait anxiety

In addition to their robust difference in trait anxiety, as illustrated by a variety of behavioral tests, HAB and LAB rats differ in their stress coping strategies, the former being more susceptible and vulnerable to stressor exposure and preferring more passive strategies. HAB rats of either gender show signs of a hyper-reactive hypothalamic-pituitary-adrenocortical (HPA) axis, thus resembling psychiatric patients. As shown by in situ hybridization and microdialysis in freely behaving animals, both the expression and release of vasopressin in the hypothalamic paraventricular nucleus are higher in HAB than in LAB rats, thus contributing to the HPA axis hyperdrive. Accordingly, in HAB animals, administration of a V1 receptor antagonist normalized the pathological outcome of the dexamethasone/corticotropin-releasing hormone test and triggered behavioral changes toward reduced anxiety and active stress coping. Pharmacological validation has revealed signs of depressive-like behavior, as HAB but not LAB rats have shown more active stress coping behavior and a normalized HPA axis after treatment with paroxetine. Of interest, this antidepressant reduced the hypothalamic overexpression of vasopressin; this novel mechanism of action is likely to contribute to paroxetine effects on both behavioral and neuroendocrine parameters. Cross-mating and cross-fostering paradigms showed that the divergent emotionality in HAB vs. LAB rats is determined genetically, rather than postnatally through maternal behavior. As the behavioral and neuroendocrine phenotyping pointed to the vasopressin gene as a candidate gene critically involved in anxiety, preliminary genetic approaches have been focused on this gene, revealing single nucleotide polymorphisms (SNPs) in the promotor area of the vasopressin gene in HAB, but not LAB rats. HAB/LAB rats are thus proving to be a unique animal model to identify and characterize neurobiological, neuroendocrine, and genetic correlates of trait anxiety, and perhaps depression, in humans.     

Katzenkratzkrankheit Eine wichtige Differentialdiagnose der Lymphadenopathie

Zusammenfassung Wir berichten über 2 F?lle von Katzenkratzkrankheit. Diese Erkrankung z?hlt zu den seltenen Ursachen einer Lymphadenopathie. Die Verdachtsdiagnose stützt sich auf Katzenkratzer in der Anamnese und die typischen Befunde mit Lymphknotenschwellung im Bereich der Prim?rl?sion.      

Human immunodeficiency virus case detection and antiretroviral therapy enrollment among children below and above 18 months old: A comparative analysis from Cameroon

While pediatric human immunodeficiency virus (HIV) testing has been more focused on children below 18 months through prevention of mother to child transmission of HIV (PMTCT), the yield of this approach remains unclear comparatively to testing children above 18 months through routine provider-initiated testing and counselling (PITC). This study aimed at assessing and comparing the HIV case detection and antiretroviral therapy (ART) enrolment among children below and above 18 months of age in Cameroon. This information is required to guide the investments in HIV testing among children and adolescents.We conducted a cross-sectional study where we invited parents visiting or receiving HIV care in 3 hospitals to have their children tested for HIV. HIV testing was done using polymerase chain reaction (PCR) and antibody rapid tests for children <18 months and those ≥18 months, respectively. We compared HIV case detection and ART initiation between the 2 subgroups of children and this using Chi-square test at 5% significant level.A total of 4079 children aged 6 weeks to 15 years were included in the analysis. Compared with children <18 months, children group ≥18 months was 4-fold higher among those who enrolled in the study (80.3% vs 19.7%, P < .001); 3.5-fold higher among those who tested for HIV (77.6% vs 22.4%, P < .001); 6-fold higher among those who tested HIV+ (85.7% vs 14.3%, P = .24), and 11-fold higher among those who enrolled on ART (91.7% vs 8.3%, P = .02).Our results show that 4 out of 5 children who tested HIV+ and over 90% of ART enrolled cases were children ≥18 months. Thus, while rolling out PCR HIV testing technology for neonates and infants, committing adequate and proportionate resources in antibody rapid testing for older children is a sine quo none condition to achieve an acquired immunodeficiency syndrome (AIDS)-free generation.