Implantation of Active Can Implantable Defibrillators in the right Pectoral Region

Routinely the active can ICD is placed in the left side pectoral position, which theoretically gives optimal conditions for a low defibrillation threshold. Some patients, bowever, demand a right pectoral position, which possibly could result in a bigger defibrillation threshold. A right pectoral position was used in 3 of 85 active can ICDs implanted in our institution from 1994. the DFT was 12 J in two and 18 f in one patient. Thus, right pectoral implantation is feasible and offers an alternative approach in selected patients.     

Frontal versus transcorneal stimulation to induce maximal electroshock seizures or kindling in mice and rats

Frontal stimulation, i.e. electrical stimulation where electrodes are pressed on the skin of the intact frontal skull of mice or rats, may represent a more humane alternative to the widely used transcorneal stimulation to induce electroshock seizures. The aim of this work was to directly compare transcorneal and frontal stimulation in eliciting maximal electroshock-induced seizures (MES) in mice and the anticonvulsant effect of carbamazepine (CBZ) and phenytoin (PHT) on thus produced seizures. In addition, we stimulated mice and rats repeatedly via transcorneal and frontal electrodes to see whether kindling is produced by this procedure. Two electroshock tests were used in mice, i.e. maximal electroshock seizure threshold (MEST) test and MES generated by supramaximal stimulation (50 mA). Frontal stimulation resulted in lower convulsive threshold than in the case of corneal stimulation. Both CBZ and PHT produced dose-dependent increases in seizure threshold for both sites of stimulation, i.e. transcorneal and frontal. As regards type of electrodes, higher doses of PHT were required to increase seizure threshold in the case of frontal than transcorneal stimulation. Supramaximal stimulation (50 mA) yielded comparable ED₅₀ values regardless of the site of stimulation. Furthermore, once-daily stimulation of mice, regardless of the placement of electrodes, did not induce any changes in convulsive threshold. We also attempted to kindle mice and rats via corneal and frontal electrodes by repetitive electrical stimulation using currents which initially did not produce generalized clonic seizures. Mice were stimulated once daily for 2 s with 3 mA (corneal electrodes) or 2 mA (frontal electrodes) and rats were stimulated twice daily for 4 s at 8 mA (corneal electrodes) or 5 mA (frontal electrodes). With corneal stimulation in rats there was a clear progression of kindling development which was not the same in nature when compared with corneally-stimulated mice. Frontal stimulation did not produce kindling. Moreover, corneal stimulation was better tolerated by rats, while in mice high mortality was seen after either method of current delivery. Our data indicate that frontal electrodes can be used as an alternative to transcorneal stimulation to produce MES by supramaximal or threshold current intensities as screening procedures in antiepileptic drug (AED) development. Nevertheless, this type of stimulation cannot be used to produce minimal electroshock seizures and seems not to be useful to produce kindling in rats and mice.     

Attitudes to social issues in medicine: a comparison of first-year medical students with first-year students in non-medical faculties

The emphasis on academic achievement in medical student selection has given rise to the fear that students entering medicine may comprise a homogeneous group with tendencies towards academic and scientific pursuits rather than humanistic and person-oriented health care. The Attitudes to Social Issues in Medicine (ATSIM) scale was administered to first-year Australian medical students and first-year students in other faculties including students with significantly lower academic performance measured by high school examination scores. The medical student group was found to be less conservative towards general social issues than students enrolled in commerce and science faculties and scored equally with arts students. Greater conservatism was, however, apparent in those areas which most closely affect the doctor's role. Medical students were less positive than other student groups in their attitudes towards increased government control of the medical profession, the contribution of allied health professionals and the importance of social aspects of illness. On attitudes to issues such as prevention and doctor-patient relationships which do not challenge the knowledge base or traditional role and status of the medical profession, however, medical students demonstrate equal or greater concern compared with other student groups.     

Studying Weak Central Coherence at Low Levels: Children with Autism do not Succumb to Visual Illusions. A Research Note

While anecdotal reports of abnormal perceptual experiences in autism abound, there have been to date no experimental studies showing fundamental perceptual peculiarities. The present paper reports results from a first study of low-level visual integration in autism. Twenty-five subjects with autism, 21 normal 7- and 8-year-olds, and 26 children with learning difficulties were asked to make simple judgements about six well-known visual illusions. Two conditions were used, in an attempt to explore group differences; standard two-dimensional black and white line drawings, and the same figures augmented with raised coloured lines. The subjects with autism were less likely to succumb to the two-dimensional illusions than were the other groups, and were less aided by the three-dimensional disembedded' condition. These striking results are discussed with reference to the 'central coherence' account of autism.     

积极、消极情感在社区老年高血压患者疾病感知与健康促进行为之间的双重中介作用

目的 探讨社区老年高血压患者疾病感知和健康促进行为的关系及积极、消极情感在两者之间的中介作用。方法 采用疾病感知问卷简化版(BIPQ)、老年人健康促进行为量表(GHP),积极、消极情感量表(PANAS)对2021年12月至2022年2月广州市3家社区卫生服务中心和1家三甲医院的高血压门诊就诊的240例老年高血压患者进行横断面调查。构建结构方程模型,并采用Bootstrap抽样法对模型进行验证。结果 社区老年高血压患者疾病感知总分为(24.74±4.45)分,健康促进行为总分为(71.78±8.70)分,积极情感总分为(20.15±3.55)分,消极情感总分为(12.16±3.11)分。相关分析显示,疾病感知、消极情感与健康促进行为呈负相关(P<0.01);积极情感与健康促进行为呈正相关(P<0.01);疾病感知与消极情感呈正相关(P<0.01),而与积极情感呈负相关(P<0.01)。双重中介结构方程模型显示：拟合优度检验(χ²/df)=1.641、近似残差均方根(RMSEA)=0.054、比较拟合指数(CFI)=0.961。积极、消极情感在...     

Comparison of mathematically determined blood lactate and heart rate “threshold” points and relationship with performance

Summary The purpose of this study was to investigate the relationship between threshold points for heart rate ( ) and blood lactate (Th_1a) as determined by two objective mathematical models. The models used were the mono-segmental exponential (EXP) model of Hughson et al. and the log-log (LOG) model of Beaver et al. Inter-correlations of these threshold points and correlations with performance were also studied. Seventeen elite runners (mean, SD = 27.5, 6.5 years; 1.73, 0.05 m; 63.8, 7.3 kg; and maximum oxygen consumption of 67.8, 3.7 ml · kg^–1 · min^–1) performed two maximal multistage running field tests on a 183.9-m indoor track with inclined turns. The initial speed of 9 km · h^–1 (2.5 m · s^–1) was increased by 0.5 km · h^–1 (0.14 m · s^–1) every lap for thef _c test and by 1 km · h^–1 (0.28 m · s^–1) every 4 min for the la test. After fitting the la or thef _c data to the two mathematical models, the threshold speed was assessed in the LOG model from the intersection of the two linear segments (LOG-1a; LOG-f _c) and in the EXP model from a tangent point (TI-1a; TI-f _c). Th_1a and speeds computed with the two models were significantly different (P<0.001) and poorly correlated (LOG-1a vs LOG-f _c:r=0.36, TI-1a vs TI-f _c:r=0.13). In general, were less well correlated with performance than Th_1a. With two different objective mathematical models, this study has shown significant differences and poor correlations between Th_1a and . Thus thef _c inflection point with Conconi's protocol is a poor indicator of the la breakpoint with a conventional multistage protocol and a weaker indicator of running performance.     

Trajectory of contact region on the fingerpad gives the illusion of haptic shape

When one explores a solid object with a fingertip, a contact region is usually defined. When the trajectory of this region on the fingerpad is artificially controlled so as to resemble the trajectory that is normally present while exploring a real object, the experience of shape is created. In order to generate appropriate local deformation trajectories, we built a servo-controlled mechanism that rolled a flat plate on the fingerpad during the manual exploration of virtual surfaces so that the plate was kept tangent to a virtual shape at the point of virtual contact. An experiment was then designed to test which mode of exploration maximized the shape information gain: active versus semi-active exploration, where semi-active exploration is when one hand touches passively and the other moves the target object, and the use of single versus multiple points of contact. We found that subjects were able to perform curvature discrimination at levels comparable to those achieved when using direct manual contact with real objects, and that the highly simplified stimulus provided by the device was a sufficient cue to give the illusion of touching three-dimensional surfaces.     

Heart Rate Perception and Heart Rate Control

Twenty-one subjects look the Autonomic Perception Questionnaire (APQ) and later were given another test of ability to perceive heart activity. The second test involved subjects' tracking of their own heart rates (HR). They were then tested for ability to increase and decrease HR from their resting baseline levels. No significant relationships were found between HR control and APQ score. HR decrease success seemed to depend mainly on respiration differences between rest and decrease periods. The subjects who achieved high scores on the heart tracking test increased HR significantly better than did low scorers. This heart perception vs HR increase relationship did not depend upon respiration rate, respiration amplitude, or baseline HR differences between high and low scorers on the tracking test. A low correlation between APQ and tracking score seemed to indicate that the two perception tests measured different attributes of the subjects.     

Conventional anticonvulsant drugs in the guinea pig kindling model of partial seizures: effects of acute phenobarbital,valproate, and ethosuximide

This study addressed the anticonvulsant effects of phenobarbital, valproate, and ethosuximide in the amygdala of kindled guinea pigs to further validate this model for the screening of anticonvulsant drugs. Behavioral toxic effects were assessed at 30 min following drug administration using quantitative locomotor tests, as well as scores on a sedation and muscle relaxation rating index. The anticonvulsant efficacy of the drugs were evaluated from measurements of afterdischarge threshold (ADT), afterdischarge duration (ADD), and behavioral seizure severity (SS) during early and late phases of kindling acquisition, and in kindled guinea pigs. ADD and SS were also measured in response to both threshold and suprathreshold kindling stimulation. All drugs exerted slight to moderate sedative effects in guinea pigs on both the behavioral tests and rating index. We found that phenobarbital exhibited effective anticonvulsant properties in guinea pigs by consistently reducing ADD and SS in response to both threshold and suprathreshold kindling stimulation. Valproate exhibited effective anticonvulsant properties at threshold stimulation and less effective properties at suprathreshold stimulation. Lastly, we found that ethosuximide lacked effective anticonvulsant action at either threshold or suprathreshold kindling stimulation. Our results indicate that the guinea pig kindling model correctly predicted the actions of phenobarbital, valproate, and ethosuximide in the treatment of partial seizures. Guinea pig amygdala kindling appears to serve as a useful and valid model for partial epilepsy.