Lifetime history of substance misuse in first-episode psychosis: prevalence and its influence on psychopathology and onset of psychotic symptoms

Introduction: Substance misuse (SM) (drug/alcohol dependence or abuse) in psychotic illness is an increasingly recognized problem. We aimed to estimate the prevalence and examine the influence of SM on age at onset of psychosis and psychopathology among patients with first‐episode psychosis. Method: One hundred seventy‐one consecutive patients with first‐episode psychosis were assessed. SM, age of onset of psychosis and psychopathology were determined using valid instruments. Results: Seventy‐seven (46%) patients had a lifetime history of SM and were predominately males, had more positive symptoms, and in the majority of cases (84%), started misusing substances before the onset of psychosis (SM‐BP). There was no difference in age of onset between patients with SM‐BP and the rest of the sample. Conclusion: Lifetime history of SM is common and may influence psychopathology, but does not appear to influence or bring forward the age at onset of psychotic symptoms.     

Arthrometric Evaluation of Stabilizing Effect of Knee Functional Bracing at Different Flexion Angles

Previous in-vivo investigations on the stabilizing efficacy of knee bracing for ACL reconstructed patients have been often limited to 20-30 degrees of knee flexion. In this study, the effectiveness of a uniaxial hinged functional brace to improve the knee stability was assessed at 30, 60 and 90 degrees of knee flexion. Arthrometry tests were conducted on 15 healthy subjects before and following wearing the brace and the tibial displacements were measured at up to 150 N anterior forces. Results indicated that functional bracing has a significant stabilizing effect throughout the range of knee flexion examined (p < 0.05). The rate of effectiveness, however, was not consistent across the flexion range, e.g., 50% at 30 degrees and only 4% at 90 degrees. It was suggested that accurate sizing and fitting as well as attention to correct hinge placement relative to the femoral condyles can limit brace migration and improve its effectiveness in mid and deep knee flexion. With using adaptive limb fittings, through flexible pads, and a polycentric joint a more significant improvement of the overall brace performance and efficacy might be obtained.

Key points

• Functional bracing improves the knee joint stability mostly in extension posture.
• Unlike the non-braced condition, the least knee joint stability appears in mid and deep flexion angles when using a hinged brace.
• Accurate sizing and fitting and attention to correct hinge placement relative to the femoral condyles can limit brace migration and improve its effectiveness in mid and deep knee flexion.
• The overall brace performance and efficacy might be improved significantly using adaptive limb fittings through flexible pads and/or polycentric joints.

Key words: Functional brace, knee, ACL injury, instability, arthrometery     

Differential carbonylation of cytoskeletal proteins in blood group O erythrocytes: Potential role in protection against severe malaria

The molecular basis for the prevalence of blood group O in regions where malaria is endemic remains unclear. In some genetic backgrounds oxidative modifications have been linked to a reduced susceptibility to severe malaria disease. Through redox proteomics, we detected differences in carbonylated membrane proteins among the different blood groups, both in Plasmodium-infected and uninfected erythrocytes (RBC). Carbonylation profiles of RBC membrane proteins revealed that group O blood shows a reduced protein oxidation pattern compared to groups A, B and AB. Upon infection with Plasmodium falciparum Dd2, erythrocytes of all blood groups showed increased oxidation of membrane proteins. By examining 4-hydroxy-2-nonenal (4-HNE) modified proteins by LC–MS/MS (liquid chromatography/mass spectrometry) we observed that, upon malaria infection, the protein components of lipid rafts and cytoskeleton were the main targets of 4-HNE carbonylation in all blood groups. Ankyrins and protein bands 4.2 and 4.1 were differentially carbonylated in group O as compared to A and B groups. During trophozoite maturation in group O erythrocytes, a steady increase was observed in the number of 4-HNE-modified proteins, suggesting a parasite-driven 4-HNE-carbonylation process. Our findings indicate a possible correlation between the protection against severe malaria in blood group O individuals and a specific pattern of 4-HNE-carbonylation of cytoskeleton proteins.     

Bone structure investigation using X-ray and neutron radiography techniques.

In this paper we report a study of the periodic variation of bone tissue humidity immediately after death using both neutron and X-ray radiography techniques. After death, bone tissue experiences sequential change over time. This change consists of organic and inorganic phase variations of the bone structure, as well as gradual reduction of the bone's water content. These variations are investigated by periodically imaging dead bone using X-ray and neutron radiography. Chemical separation techniques such as calcification and decalcification were used to separate the organic and inorganic phases of the bone. Comparison between X-ray and neutron radiographs of bone following phase separation can be potentially used to investigate the bone disease or to determine a cause of death. In our experiments, we use adult rat femur bones, and the interpretations of these results are presented based on our understanding of bone structure and images produced by neutron and X-ray photon interactions.     

Factors influencing alcohol and illicit drug use amongst medical students

Alcohol, illicit drug use, and other lifestyle variables, as well as stress, anxiety and personality were evaluated in 194 first year medical students. 45% of the students reported drinking above the recommended UK limits for alcohol consumption. The age at which the first full drink of alcohol was taken was predictive of the current level of alcohol use. Cannabis was the most frequently used illicit drug (45%). There were significant positive associations between alcohol consumption and experiences such as missing study, becoming more sexually involved and getting into a physical fight or argument. There were also significant positive associations between the personality characteristic of psychoticism and alcohol and illicit drug consumption. The effectiveness of current health education on alcohol and illicit drugs is questioned.     

The prevalence of comorbid substance misuse and its influence on suicidal ideation among in-patients with schizophrenia

OBJECTIVE: To estimate the prevalence, and identify the clinical correlates of comorbid substance misuse (abuse or dependence) among readmissions with schizophrenia, particularly to establish whether comorbid substance misuse is associated with higher rates of depressive symptoms and suicidal ideation. METHOD: Over 12 months, consecutive readmissions from a catchment area psychiatric service with DSM-IV schizophrenia/schizoaffective disorder were assessed using clinical assessments of symptomatology including depression, insight and compliance. Comorbid substance misuse was diagnosed using DSM-IV criteria. RESULTS: Of 102 readmissions 40% had lifetime, while 20% had current comorbid substance misuse and were predominately young males. Comorbid substance misuse had no statistically significant impact on positive, negative or depressive symptomatology. However, those currently misusing substances reported more suicidal ideation compared with past or non-substance misusers. CONCLUSION: Readmissions with comorbid substance misuse were more likely to report suicidal ideation, and may represent a group of individuals who are at higher risk of suicide.     

Effect of saliva flow rate on saliva phenytoin concentrations: implications for therapeutic monitoring

The effect of atropine-induced reductions in saliva flow rate on saliva phenytoin concentrations were evaluated in a randomised placebo-controlled crossover study in a group of epileptic patients stabilised on the drug.Pretreatment with atropine caused significant reductions in saliva flow rates during the first 4 h, compared to saline. The AUC_{0–4 h} for saliva flow rate was significantly reduced by atropine (245 g vs 327 g) and the saliva phenytoin AUC_{0–4 h} was significantly increased (5.6 g · ml^–1 · h vs 4.5 g · ml^–1 · h) without affecting plasma phenytoin concentrations. The saliva/plasma phenytoin AUC_{0–4 h} ratio was therefore significantly increased by atropine (0.15 vs 0.12). However, there was a poor correlation between saliva/plasma phenytoin concentration ratios and saliva flow rates for the two treatments in the individual patients (correlation coefficient ranged from 0.25 to 0.65).These findings demonstrate that saliva phenytoin concentrations are increased by reductions in saliva flow rate. Caution is therefore required when saliva phenytoin concentrations are used for therapeutic monitoring in the presence of factors which may affect saliva flow rate.     

Prospective evaluation of neurological soft signs in first-episode schizophrenia in relation to psychopathology: state versus trait phenomena

BACKGROUND: Although patients with schizophrenia have increased rates of neurological soft signs, few studies have examined prospectively their trait or state characteristics in relation to psychopathology. METHOD: In a prospective study of 97 patients with first-episode schizophrenia (DSM-IV criteria) we assessed neurological soft signs and psychopathology at presentation and at 6 month follow-up for 73 cases. To establish whether soft signs were associated with variations in clinical state, neurological soft signs were measured using two validated examinations (Neurological Evaluation Scale and Condensed Neurological Examination); psychopathology was assessed using the Positive and Negative Syndrome Scale. RESULTS: There was significant improvement in overall neurological function, primarily in motor-related and cortical signs, which were associated with improvement in psychopathology. Conversely, 'harder' signs were unrelated to improvement in psychopathology. CONCLUSIONS: Neurological soft signs in schizophrenia are heterogenous. Motor and cortical signs evidence state-like characteristics and vary with clinical course, while 'harder' signs evidence more static, trait-like characteristics in accordance with a neurodevelopmental basis.