Use of Telemetered Electrograms in the Assessment of Normal Pacemaker Function

The facility of direct real-time endocardial electrogram recording offered by newer pacemaker models can be helpful in the assessment of normal pacemaker function. Confirmation of the main hallmarks of sensing (amplitude, slew rate, and timing of the electrogram) can be achieved. Assessment of pacing capture also can be made; techniques for further analysis using external signal averaging can enhance this. The measurement of atrial and ventricular electrograms by telemetry has led to alterations in the protocol used at implantation to allow for the input impedance of the sensing circuit of the pacemaker. Accurate measurements of retrograde VA conduction times and confirmation of normal upper rate limit behavior of ODD pacemakers can be achieved simply and reliably using telemetered electrograms from the permanent pacemaker system.     

Worldwide epidemiology and modes of transmission of delta hepatitis

Conclusions Since the discovery of HDV in 1977 byRizzetto and collegues (10), several studies regarding the pathogenesis, natural history and epidemiology of this infection have been accumulated. It emerges that HDV is an agent with unusual biologic properties which requires HBV replication for its expression. Given the obligatory association between HDV and HBV, transmission of HDV follows the same routes of HBV transmission. This implies that one expects HDV infection to be much more prevalent in countries with high HBsAg carrier rates. This is true in most areas of the world but not in Far East Asia. Endemicity of HDV is maintained in the community through the network of HBsAg carriers. HDV can be transmitted to HBV positive and negative individuals, but survives only after encountering the carrier. Recent outbreaks of severe epidemics of fulminant hepatitis due to HDV among the Yucpa Indians in Northern Venezuela, pointed out very clearly that HDV superinfection is an ominous risk for all populations where HBV is endemic.     

Urinary excretion of 5-oxoproline (pyroglutamic aciduria) as an index of glycine insufficiency in normal man

1. The evidence is accumulating to suggest that glycine, the simplest amino acid, is conditionally essential in man. Benzoic acid, by conjugation with glycine to form hippuric acid, is known to deplete the free glycine pool of the body. Glycine is one substrate for the enzyme glutathione synthase (EC 6.3.2.3) and in the inborn error of metabolism in which glutathione synthase function is defective, increased quantities of 5-oxoproline are excreted in the urine. 2. An oral dose of 4-10 g sodium benzoate was given to six normal adults to deplete the metabolic pool of glycine, and the urinary excretion of 5-oxoproline was followed for 6 h. In five of the six, a significant increase in the urinary 5-oxoproline was seen within 3 h. 3. These findings show that 5-oxoprolinuria can result from limited glycine availability, and may provide a useful test for assessing glycine sufficiency in a range of physiological and pathological states.     

Coping with economic crisis: policy development in China and India

This paper explores health policy options in response to economiccrises in developing countries. The paper is based upon thepremise that policy is best pursued within a broad understandingof the determinants of health of populations. To provide anempirical base for analysis, the health status and health caresystems of China and India are compared. A conceptual frameworkon the determinants of the health status of populations is thendeveloped, incorporating both the performance of health caresystems and non-medical factors which influence health. Usingthe China and India experiences, the paper reviews the strengthsand weaknesses of traditional tools used in the analysis ofhealth policy. Significant policy change, it is argued, is bestimplemented through structural change of several health caresystem components simultaneously. Health policy analysis, itis further argued, must consider the broader political economyof the society. Moreover, there remain many imperfectly understoodsociocultural aspects of behaviour which enable some familiesto produce good health despite economic constraints. The paperconcludes that economic crisis presents an opportunity for astructural review of a society's health systems. Health policyoptions in response to economic crisis cannot be confined tothe health care sector. Rather, health policy should be viewedas only one, perhaps important, element of a package of socioeconomicpolicy options. Critical to policy choices are reliable informationon the condition of the poor and high political priority tominimize the adverse impact of economic crisis on the health,nutrition and social welfare of disadvantaged groups.     

Percutaneous management of lymphatic fluid collections

Eight lymphatic fluid collections were drained percutaneously. There were no immediate or late complications. Seven patients had follow-up; 1 required surgical drainage of a residual or recurrent lymphocele, and another had reaccumulated fluid in a lymphocele which was detected on autopsy. The remaining lymphatic collections responded to percutaneous drainage. Percutaneous drainage is safe and can be an effective tool in the management of lymphatic collections.     

Toewebs as a source of Gram-negative bacilli

The prevalence of Gram-negative bacilli on the toewebs was 8% in normal students, 24% in hospital outpatients with suspected Tinea pedis, 41% in industrial workers wearing protective clothing and 58% in coal miners. Prevalence was greatest in those exposed to wet working conditions. In miners, the presence of Gram-negative bacilli was related to symptoms of itching/soreness and cracking/fissuring, and was negatively related to malodour, but this latter trend was reversed in outpatients and in industrial workers. The feet are a source of many 'enteric' and 'environmental' bacilli and could contribute to infection elsewhere than in the toewebs themselves.     

Modulating effects of posttraining epinephrine on memory: Involvement of the amygdala noradrenergic system

These experiments examined the effects, on retention, of posttraining intra-amygdala administration of norepinephrine (NE), and propranolol. Rats were trained on a one-trial step-through inhibitory avoidance task and tested for retention 24 h later. Injections were administered bilaterally (1.0 microliter/injection) through chronically-implanted cannulae. Low doses of NE (0.1 or 0.3 microgram) administered shortly after training enhanced retention while higher doses (1.0 or 5.0 micrograms) were ineffective. Retention was not affected by NE administered 3 h after training. The effect of intra-amygdala NE on retention is blocked by simultaneous administration of propranolol (0.2 microgram). This finding suggests that the memory-enhancing effect of NE may be mediated by beta-receptors. Posttraining intra-amygdala NE also attenuated the retention deficit produced by adrenal demedullation. Further, intra-amygdala injections of propranolol (0.2 microgram) blocked the enhancing effect, on retention, of posttraining s.c. injections of epinephrine. These findings suggest that activation of noradrenergic receptors in the amygdala may be involved in memory processing and may play a role in the memory-modulating effect of peripheral epinephrine.