Sensorimotor prediction and memory in object manipulation.

Notes that when people lift objects of different size but equal weight, they initially employ too much force for the large object and too little force for the small object. However, over repeated lifts of the two objects, they learn to suppress the size–weight association used to estimate force requirements and appropriately scale their lifting forces to the true and equal weights of the objects. Thus, sensorimotor memory from previous lifts comes to dominate visual size information in terms of force prediction. Here the authors ask whether this sensorimotor memory is transient, preserved only long enough to perform the task, or more stable. After completing an initial lift series in which they lifted equally weighted large and small objects in alternation, 24 18–28 yr olds then repeated the lift series after delays of 15 min or 24 hrs. In both cases, participants retained information about the weights of the objects and used this information to predict the appropriate fingertip forces. This preserved sensorimotor memory suggests that participants acquired internal models of the size–weight stimuli that could be used for later prediction. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Aldosterone and dexamethasone stimulate calcineurin activity through a transcription-independent mechanism involving steroid receptor-associated heat shock proteins

1. PD 81,723 has been shown to enhance binding of adenosine to A1 receptors by stabilizing G protein-receptor coupling ('allosteric enhancement'). Evidence has been provided that in the perfused hearts and isolated atria PD 81,723 causes a sensitization to adenosine via this mechanism. 2. We have studied the effect of PD 81,723 in guinea-pig isolated atrial myocytes by use of whole-cell measurement of the muscarinic K+ current (I[K(ACh)]) activated by different Gi-coupled receptors (A1, M2, sphingolipid). PD 81,273 caused inhibition of I[K(ACh)] (IC50 approximately 5 microM) activated by either of the three receptors. Receptor-independent I[K(ACh)] in cells loaded with GTP-gamma-S and background I[K(ACh)], which contributes to the resting conductance of atrial myocytes, were equally sensitive to PD 81,723. At no combination of concentrations of adenosine and PD 81,723 could an enhancing effect be detected. 3. The compound was active from the outside only. Loading of the cells with PD 81,723 (50 microM) via the patch pipette did not affect either I[K(ACh)] or its sensitivity to adenosine. We suggest that PD 81,723 acts as an inhibitor of inward rectifying K+ channels; this is supported by the finding that ventricular I(K1), which shares a large degree of homology with the proteins (GIRK1/GIRK4) forming I[K(ACh)] but is not G protein-gated, was also blocked by this compound. 4. It is concluded that the functional effects of PD 81,723 described in the literature are not mediated by the A1 adenosine receptor-Gi-I[K(ACh)] pathway.     

Entamoeba histolytica: computer-assisted modeling of phosphofructokinase for the prediction of broad-spectrum antiparasitic agents

Approximately 34 cases of intracranial tuberculomas with paradoxical response to antituberculous chemotherapy have been documented worldwide. In most of the previously reported cases of this entity an associated tuberculous meningitis has been reported. The majority of these patients were children or young adults, who had inoperably located intracranial tuberculomas in high risk regions developing a few weeks or months after the start of appropriate chemotherapy. 53% of them recovered completely, 37% improved with mild neurological deficits and 10% died. It is interesting that these intracranial tuberculomas developed or enlarged at a stage when systemic tuberculosis was being treated successfully. We report our recent experience with these potentially curable tumours of the central nervous system. The literature is reviewed and diagnostic and therapeutic considerations are discussed. The possible immunological mechanisms of this phenomenon are analysed. In conclusion, patients, who are suspected to be suffering from CNS-tuberculosis should receive a prolonged (12-30 months) course of effective antituberculous therapy. Evidence of new intracranial tuberculomas or the expansion of older existing lesions require no change in the antituberculous drug programme. In such cases systemic dexamethasone as adjuvant therapy for 4 to 8 weeks is worthwhile and effective. Surgical intervention may be necessary in situations with acute complications of CNS tuberculosis such as shunting procedures for the treatment of hydrocephalus. When the diagnosis is not firm and there is no response to therapy within 8 weeks, a stereotactic biopsy of a suspected tuberculoma should be performed. If the largest lesion is not located in high risk deep regions of the brain, it should be total removed surgically. With this combined management, a satisfactory outcome can be obtained in the majority of cases.     

DNA-based immunization against hepatitis B surface antigen (HBsAg) in normal and HBsAg-transgenic mice

Hepatitis B virus (HBV) remains a serious worldwide health problem and the possibility to control it will depend on the availability of safe, effective and affordable vaccines. Recombinant protein or plasma-derived vaccines containing HBV surface antigen (HBsAg) are safe and generally efficacious, however, they are too expensive for widespread use in areas of HBV endemicity and are only partially effective for treatment of HBV chronic carriers. Immunization of mice by injection of HBsAg-expressing plasmid DNA results in rapid induction of strong and long-lasting humoral and cell-mediated immune responses. Here we report optimization of the humoral response with the use of necrotizing agents, co-expression of cytokines or co-stimulatory molecules and formulation of the DNA with cationic liposomes. DNA-based immunization of HBsAg-transgenic mice can also overcome non-response to HBsAg. Thus, DNA vaccines against HBV may be useful for both prophylactic and therapeutic purposes.     

Beta1B subunit of voltage-dependent Ca2+ channels is predominant isoform expressed in human neuroblastoma cell line IMR32

BACKGROUND: In adults, Helicobacter pylori infection is always associated with gastritis or ulcer. However, very active gastritis and ulcers are rarely seen in children. The aim of the present work was to study the relationships between H. pylori and gastric mucosa in children. METHODS: Eighty infected children and adolescents including 48 (60%) neurologically impaired institutionalized patients, aged 2 months-22 years (mean 11.7 +/- 5.2 years) were studied retrospectively. All the patients underwent gastroscopy, and three antral and two fundic biopsy specimens were taken for histology and bacteriology. RESULTS: A normal gastric mucosa was found in 22 of 80 patients (27.5%), whereas the others had gastritis (n = 58, 72.5%). There were no statistical differences between patients with normal histology and those presenting with gastritis for age, sex, ethnic background, symptoms, and the degree of bacterial colonization. The macroscopic aspect of gastritis was less frequently found in children with a normal histology compared with those with histological gastritis (p < 0.001). CONCLUSIONS: These data show that H. pylori infection can be associated with a normal gastric histology in children.     

The impact of cardiology on the collective effective dose in the North of England

Two cardiology X-ray rooms were monitored with dose-area product meters as part of a Regional Patient Dosimetry Programme. Dose-area product measurements on over 2000 patients undergoing examinations in the cardiology rooms are presented. The data have been corrected according to patient size where possible. In room A mean dose-area product values for coronary angiography, coronary angioplasty, radiofrequency ablation and mitral valvuloplasty were found to be 47.7, 72.2, 91.1 and 161.9 Gy cm2 respectively. In room B mean dose-area product values for coronary angiography and coronary angioplasty were found to be 23.4 and 51.6 Gy cm2 respectively. Observational studies were used to deduce the typical projections and technique factors. This typical examination was used to simulate an angiogram from which it was possible to derive factors to convert measured dose-area product values into estimates of effective dose. In room A, the effective doses were estimated to be 9.4, 14.2, 17.3 and 29.3 mSv for coronary angiography, coronary angioplasty, radiofrequency ablation and mitral valvuloplasty, respectively. The effective doses during coronary angiography and coronary angioplasty, performed in room B, were found to be 4.6 and 10.2 mSv, respectively. A regional survey of the frequency of these cardiac procedures was performed. It was deduced that the annual collective effective dose from these cardiac procedures in the North of England, the former Northern Region, was 45.7 manSv.     

Plasma Asp13-Ki-ras oncoprotein expression in vinyl chloride monomer workers in Taiwan

Vinyl chloride (VC) workers are known to be at risk for development of liver angiosarcoma, a rare tumor. Previously, more than 80% of VC workers with liver angiosarcoma have been found to have an Asp-13 c-Ki-ras oncogene mutation, and more than 50% of VC-exposed workers without liver tumors were found to have Asp13-Ki-ras oncoprotein in their plasma. Some workers in Taiwan had also been exposed to VC, and some have contracted liver tumors. In this study, we used enhanced chemiluminescence Western blotting to detect Asp13-p21-Ki-ras in the sera of VC-exposed workers in Taiwan. There were 14 of 113 (12.4%) VC workers positive for the Asp13-Ki-ras oncoprotein in plasma, but 0 of 18 controls were positive. There were 10 of 69 (14.5%) plasma-positives among the more highly exposed (> 1000 ppm-months) workers and 4 of 48 (9.1%) plasma-positives among the lesser exposed (< or = 1000 ppm-months). Compared with the unexposed controls, the odds ratios (and 95% confidence intervals [CI]) for plasma-positivity were 4.11 (95% CI = 0.21, 80.4) in the lower-exposed workers and 6.53 (95% CI = 0.37, 116.9) in the higher-exposed workers, and there was a linear trend between exposure and plasma-positivity (P = 0.073). After adjusting for age and drinking status, the odds ratios (and 95% CIs) were 1.64 (95% CI = 0.17, 15.8), and 2.65 (95% CI = 0.42, 16.8), respectively, and there was a significant linear trend between exposure and plasma-positivity (P = 0.048). In summary, Asp13-Ki-ras oncoprotein can be found in the plasma of VC workers in Taiwan, and a significant dose-response relationship exists between plasma oncoprotein expression and VC exposure.     

Personality, mood, and cognitive processing of emotional information: three conceptual frameworks

This article reviews evidence for the roles that mood states and personality traits play in the processing of emotion-congruent information across different cognitive tasks. Evidence is reviewed for 3 emotion-congruency frameworks, each summarizing a different route to emotional processing: the traditional approach, a moderation approach, and a mediation approach. Most of the traditional literature includes studies that examine the effects of moods and traits on emotional processing separately; these studies have yielded some inconsistent findings. The moderation and mediation approaches offer potential solutions to the lack of consistency obtained in the traditional literature by allowing for the combined effects of personality traits and mood states on the processing of emotional information. The moderation approach suggests that mood states interact with individual differences in emotion-relevant personality traits to influence emotion-congruent processing. The mediation approach suggests that personality traits predispose individuals to certain mood states, which then influence emotional processing. These approaches provide a framework for understanding the literature and a starting point for future research on emotion-congruent processing.     

Screening calcaneal ultrasound and risk factors for osteoporosis among lesbians and heterosexual women

We compared calcaneal ultrasound measurements (speed of sound [SOS], broadband ultrasound attenuation [BUA], and stiffness index [SI]) of lesbian and heterosexual women to examine the medical and lifestyle risk factors for osteoporosis in each group. This was an exploratory, community-based, cross-sectional study. Subjects were mailed food frequency, health, and physical activity questionnaires. Weight, height, and calcaneal ultrasound measurements were taken at one office visit. In communities in southern and eastern Maine, 71 lesbians and 77 heterosexual women between the ages of 30 and 50 with regular menses and in good general health were the subjects. Statistical analysis used t-tests and chi-square tests to evaluate differences between study groups. Linear regression models were used to evaluate risk factors for low calcaneal ultrasound measurements. There were no differences between the lesbian and heterosexual women in age, body mass index (BMI), exercise, calcium intake, alcohol use, or calcaneal ultrasound measurements. There was a positive association between BUA and both BMI and alcohol consumption (p < 0.01). Antidepressant use significantly reduced SOS and SI (p < 0.05). There were no differences in calcaneal ultrasound measurements between lesbian and heterosexual women. BMI was strongly and positively associated with BUA. Antidepressant use in both populations was associated with a significant reduction in calcaneal bone mass. Studies are needed to define the relationship of depression and its treatment to bone mineral density and the future risk of osteoporosis.