Validation of a new method for building a three-dimensional physical model of the skull and dentition

We present a new method for replicating the skull and occlusal surface with an accurate physical model that could be used for planning orthognathic surgery. The investigation was made on 6 human skulls, and a polyvinyl splint was fabricated on the dental cast of the maxillary dentition in each case. A cone beam computed tomogram (CBCT) was taken of each skull and a three-dimensional replica produced. The distorted dentition (as a result of magnification errors and streak artefacts) was removed from the three-dimensional model and replaced by new plaster dentition that was fabricated using the polyvinyl splint and a transfer jig replication technique. To verify the accuracy of the method the human skulls and the three dimensional replica model, with the new plaster dentition in situ, were scanned using a laser scanner. The three-dimensional images produced were superimposed to identify the errors associated with the replacement of the distorted occlusal surface with the new plaster dentition. The overall mean error was 0.72 and SD was (0.26)mm. The accuracy of the method encouraged us to use it clinically in a case of pronounced facial asymmetry.     

Life stressors and resources and the 23-year course of depression

Background

Life stressors and personal and social resources are associated with depression in the short-term, but little is known about their associations with the long-term course of depression. The current paper presents results of a 23-year study of community adults who were receiving treatment for depression at baseline (N=382).

Methods

Semi-parametric group-based modeling was used to identify depression trajectories and determine baseline predictors of belonging to each trajectory group.

Results

There were three distinct courses of depression: high severity at baseline with slow decline, moderate severity at baseline with rapid decline, and low severity at baseline with rapid decline. At baseline, individuals in the high-severity group had less education than those in the moderate-severity group, and more medical conditions than those in the moderate- and low-severity groups. Individuals in the high- and moderate-severity groups evidenced less psychological flexibility, and relied more on avoidance coping than individuals in the low-severity group.

Limitations

Results are limited by use of self-report and lack of information about depression status and life events in the periods between follow-ups.

Conclusions

These results assist in identifying groups at high risk for a long-term course of depression, and will help in selecting appropriate interventions that target depression severity, coping skills and management of stressors.     

TNFR2 expression is a hallmark of human memory B cells with suppressive function

Tumor Necrosis Factor Receptor 2 (TNFR2) expression is increasingly being linked to tolerogenic immune reactions and cells with suppressor function including a subset of T-regulatory cells. B-regulatory cells play an important role in control of T-cell responses and inflammation. Recently, we described TNFR2 as a marker for IL-10-producing B cells, a hallmark of this cell subset. Here, we demonstrate that proliferation of T cells is reduced in the presence of TNFR2 positive human memory B cells generated with TLR9 ligand, while TNFR2- and TNFR2+CD27- B cells display costimulatory activity. Our data further reveal that IL-10 secretion is characteristic of IgM+ naïve and memory B cells but suppressive activity is not restricted to IL-10: (i) the inhibitory effect of TNFR2+ switched memory B cells was comparable to that exerted by TNFR2+ IgM+ memory B cells although IL-10 secretion levels in the cocultures were lower; (ii) supernatants from TNFR2+ memory B cells failed to suppress T-cell proliferation. Based on our findings, we propose that formation of Breg is a specific characteristic of human memory B cells undergoing terminal differentiation. Our data further corroborate that TNFR2 represents a viable marker for identification of memory B cells with regulatory function.     

Predictive value of dopamine transporter SPECT imaging with [<Superscript>123</Superscript>I]PE2I in patients with subtle parkinsonian symptoms

Purpose  

To examine the diagnostic sensitivity and specificity of dopamine transporter SPECT imaging with a highly dopamine transporter selective radioligand. The study included consecutively enrolled, drug-naive patients with an average short history of parkinsonian motor symptoms, referred for diagnostic scanning.     

Acute social defeat does not alter cerebral 5‐HT2A receptor binding in male Wistar rats

It has been hypothesized that effects of uncontrollable stress on serotonin receptor expression contribute to the etiology of stress‐related disorders like depression. While the serotonin‐2A receptors (5‐HT_2AR) are thought to be important in this context, only few studies examined effects of stress on this receptor subtype. In this study, we therefore assessed acute and long‐term changes in 5HT_2AR binding after social defeat stress in rats. Male Wistar rats were subjected to social defeat by placing them in the home cage of an aggressive, dominant Long Evans rat. Acute social defeat suppressed growth, but did not affect anxiety‐like behavior in an open field test. A positron emission tomography scan with the 5‐HT_2AR tracer [¹¹C]MDL 100907 1 day and 3 weeks after defeat did not show significant changes in receptor binding. To verify these results, [³H]MDL 100907 binding assays were performed in homogenates of prefrontal cortex and hippocampus, which also did not indicate any changes in B_max or K_d. These findings do not support the hypothesis that changes in 5‐HT_2AR function are a vital mechanism through which uncontrollable stress contributes to stress‐related pathologies such as depression. It remains to be determined whether effects of stress on 5HT_2AR binding depend on the nature of the stressor or on the characteristics of the rat strain. Synapse, 2014. © 2014 Wiley Periodicals, Inc.     

Characterization of the serotonin 2A receptor selective PET tracer (R)-[18F]MH.MZ in the human brain

European Journal of Nuclear Medicine and Molecular Imaging - The serotonin receptor subtype 2A antagonist (5-HT2AR) (R)-[18F]MH.MZ has in preclinical studies been identified as a promising PET...     

Dysejaculation after laparoscopic inguinal herniorrhaphy: a nationwide questionnaire study

Background  

Dysejaculation and pain from the groin and genitals during sexual activity represent a clinically significant problem in up to 4% of younger males after open inguinal herniorrhaphy. The aim of this questionnaire study is to assess the prevalence of dysejaculation and pain during sexual activity after laparoscopic inguinal herniorrhaphy on a nationwide basis.