Cognitive performance during the first year of treatment in first-episode schizophrenia: a case-control study.

BACKGROUND: Several questions remain unanswered regarding the magnitude and time course of cognitive improvement in response to antipsychotic treatment. The purpose of this study was to assess changes in cognitive performance in antipsychotic-naive or minimally medicated patients with first-episode schizophrenia during the first 12 months of treatment, in a case-control design. Patients were treated with flupenthixol decanoate depot injection, according to a standard algorithm. The primary outcome measure was change in MATRICS Cognitive Consensus Battery (MCCB) composite score over 12 months. METHOD: The sample comprised 92 patients and 100 healthy controls matched for age, sex, ethnicity and educational status. Cognitive function was assessed by means of the MCCB. RESULTS: A mixed-effects model identified a significant group × time effect (p ≤ 0.0001) for the MCCB composite score, with patients showing a greater degree of change than the controls. For the other MCCB domains there were significant group × time effects at adjusted significance level for attention and vigilance (p ≤ 0.0001), visual learning (p ≤ 0.0001), verbal learning (p = 0.005) and working memory (p ≤ 0.0001), but not for reasoning and problem solving (p = 0.04), speed of processing (p = 0.03) and social cognition (p = 0.06). There were moderate correlations between change in MCCB composite score and change in symptomatology as assessed by Positive and Negative Syndrome Scale factor analysis-derived domains. CONCLUSIONS: Substantial improvements in cognitive function were observed over and above a practice effect, and were significantly correlated with improvements in psychopathology and functionality.

A microfluidic model of hemostasis sensitive to platelet function and coagulation.

Hemostasis is the process of sealing a vascular injury with a thrombus to arrest bleeding. The type of thrombus that forms depends on the nature of the injury and hemodynamics. There are many models of intravascular thrombus formation whereby blood is exposed to prothrombotic molecules on a solid substrate. However, there are few models of extravascular thrombus formation whereby blood escapes into the extravascular space through a hole in the vessel wall. Here, we describe a microfluidic model of hemostasis that includes vascular, vessel wall, and extravascular compartments. Type I collagen and tissue factor, which support platelet adhesion and initiate coagulation, respectively, were adsorbed to the wall of the injury channel and act synergistically to yield a stable thrombus that stops blood loss into the extravascular compartment in ~7.5 min. Inhibiting factor VIII to mimic hemophilia A results in an unstable thrombus that was unable to close the injury. Treatment with a P2Y12 antagonist to reduce platelet activation prolonged the closure time two-fold compared to controls. Taken together, these data demonstrate a hemostatic model that is sensitive to both coagulation and platelet function and can be used to study coagulopathies and platelet dysfunction that result in excessive blood loss.

Emotional face processing deficit in schizophrenia: A replication study in a South African Xhosa population.

Schizophrenia is associated with a deficit in the recognition of negative emotions from facial expressions. The present study examined the universality of this finding by studying facial expression recognition in African Xhosa population. Forty-four Xhosa patients with schizophrenia and forty healthy controls were tested with a computerized task requiring rapid perceptual discrimination of matched positive (i.e. happy), negative (i.e. angry), and neutral faces. Patients were equally accurate as controls in recognizing happy faces but showed a marked impairment in recognition of angry faces. The impairment was particularly pronounced for high-intensity (open-mouth) angry faces. Patients also exhibited more false happy and angry responses to neutral faces than controls. No correlation between level of education or illness duration and emotion recognition was found but the deficit in the recognition of negative emotions was more pronounced in familial compared to non-familial cases of schizophrenia. These findings suggest that the deficit in the recognition of negative facial expressions may constitute a universal neurocognitive marker of schizophrenia.

Further studies on targeted DNA transfer to cells using a highly efficient delivery system of biotinylated transferrin and biotinylated polylysine complexed to streptavidin.

Conjugates consisting of biotinylated transferrin and biotinylated poly-L-lysine attached to streptavidin have been prepared and found to transfer luciferase plasmid DNA very efficiently to HeLa cells in the presence of chloroquine. Transfection was dependent on (i) use of biotinylated short chain polylysine containing 70 lysine residues, (ii) biotinylated transferrin containing 1-2 biotin moieties, (iii) reaction of biotinylated transferrin with streptavidin followed by isolation of the resulting conjugate on Sephadex G-200 and (iv) interaction of streptavidin-biotinylated transferrin with biotinylated polylysine giving a complex suitable for DNA transfection. It was found that if the above sequence of steps resulting in the formation of streptavidin-biotinylated transferrin/biotinylated polylysine was followed without isolation of intermediate conjugates by Sephadex G-200 chromatography, pRSVL DNA transfer was still very efficient. Transfer of luciferase DNA by the streptavidin conjugates and subsequent expression of luciferase activity was almost completely inhibited by excess free transferrin, showing that gene transfer was through the transferrin receptor pathway via receptor-mediated endocytosis. The streptavidin (bio2-transferrin) bio10-pLys70 conjugate used in the present experiments was approximately one hundred times more efficient in pRSVL DNA transfection with the HeLa cells than the previously described avidin-pLys460 (bio-transferrin) complex.

The use of orthognathic surgery to facilitate implant placement: a case report.

When attempting to restore an edentulous posterior segment of the mandible into which space the opposing maxillary segment has supererupted, it is necessary to idealize the maxillary occlusal plane to accommodate the final restoration. This report discusses superior repositioning of the posterior segment of the maxilla using rigid fixation with simultaneous implant placement into the corresponding posterior edentulous mandibular space.

The clinical utility and cost effectiveness of routine thyroid screening in adult psychiatric patients presenting at Stikland Hospital, Cape Town, South Africa.

OBJECTIVE: The use of thyroid tests to assess psychiatric patients remains debatable. Therefore, this study was conducted to examine the utility and cost effectiveness of the current protocol used in thyroid testing in adult psychiatric patients presenting at Stikland Hospital, Cape Town, South Africa. METHOD: This was a retrospective chart review conducted at Stikland Hospital between 1 January 2000 and 31 December 2005. The following data was recorded: demographic variables, clinical diagnoses at admission and discharge, number of days from admission to a thyroid test request, the reason for thyroid screening, number of thyroid tests, their yield and costs involved, as well as the action taken following an abnormal thyroid test result. RESULTS: The mean age of patients (n = 1080: n = 364 male, n = 716 female) was 42.8 years (SD ± 16.6). Pre-existing thyroid disease was documented in 70 (6%) of patients. Normal Thyroid Stimulating Hormone (TSH) test results significantly (p = 0.0001) increased, whilst abnormal TSH test results significantly (p = 0.0001) decreased from baseline to follow-up. Except for gender, the outcome of TSH screening was independent of demographic and clinical diagnoses. Only 16% of TSH tests yielded clinically significant results. CONCLUSION: The findings of this study do not support the early, routine screening for thyroid dysfunction in psychiatric patients at this facility. It is possible that thyroid screening may present with transient abnormalities of no particular clinical significance, and would therefore not be a cost effective practice.