Encainide: A new and potent antiarrhythmic agent

Encainide is a potent Class I aniarrhythmic drug that prolongs conduction in the His-Purkinje system. It produces only minimal hemodynamic changes in the normal or depressed left ventricle. Studies to date demonstrate excellent effectiveness against ventricular arrhythmia, and in comparative studies with quinidine, encainide was superior in reducing the frequency and complexity of ventricular premature beats in patients late after myocardial infarction.     

Mortality trends among refugees in Honduras, 1984-1987

Mortality data collected from 1984 to 1987 through a routine standardized health information system in the five main refugee populations of Honduras were reviewed. The direct standardized mean annual death rate for all refugees was 5.5 per 1000 population (Honduras population as reference; Honduras mortality rate: 10.1 per 1000). Mortality decreased or remained stable among Salvadoran refugees from 1984 to 1987, but increased among Nicaraguan refugees after 1985. The highest neonatal (56.1 per 1000 livebirths), infant (126.1 per 1000 livebirths) and under-five-year-olds (35.7 per 1000 child less than five years of age) mortality rates were observed in the two Nicaraguan camps. These two camps had the highest rate of newly arriving refugees. Deaths in infants and under-five-year-olds accounted for 42 and 54.1% of all deaths respectively. Of all deaths under five years of age, respiratory infections, diarrhoeal diseases and measles accounted for 21.4%, 22.1% and 4.7%, respectively. Mortality rates, particularly among under-five-year-olds and infants increased when the rate of newly arriving refugees was higher. The importance of adapted health surveillance in refugee settlements is discussed.     

Treatment of peripheral paresis-paralysis of the facial nerve using corticosteroids

The study comprised 113 patients with Bell's paresis-paralysis of the facial nerve. This group was considered as experimental while the control group involved patients with the same disease treated with oral corticosteroids. In both groups physical therapy has been applied from the very beginning of therapy. The results of the study have shown that in the group of patients treated with local corticosteroids the complete recovery was found in 82% of cases, partial in 14% and no signs of recovery in 4%. The mean time of clinical and electrophysiologic recovery was 17 days. In the control group of patients the complete recovery was found in 50%, partial in 37.5% and no improvement in 12.5%. The significant influence on the time and degree of recovery in both groups, and especially in the first group, has the time of starting the therapy; if the therapy started in the first week after the onset of the disease, the recovery was usually complete in the first group.     

Immunochemical findings in the cerebrospinal fluid in patients with inflammatory demyelinating polyradiculoneuropathy

The aim of the study was to check the hypothesis of involvement of the structure of the central nervous system on the basis of the analysis of the integrity of blood-brain barrier and the degree of IgG synthesis in the intrathecal space of patients with inflammatory demyelinization polyradiculoneuropathy. The study involved 27 patients with acute and 14 patients with chronic inflammatory demyelinization polyradiculoneuropathy. The analysis of liquor was performed in different stages of the disease. The results have shown that in the acute phase, in the phase of the maximal functional deficit there are signs of damaged integrity of the blood-brain barrier but without signs of increased intrathecal IgG synthesis. It has been concluded that there are no reliable signs of increased immunologic activity in the intrathecal space of patients with inflammatory demyelinization polyradiculoneuropathy.     

Association of bacteriuria and urinary nitrosamine formation with Schistosoma haematobium infection in the Qalyub area of Egypt

In Egypt, bladder cancer incidence is high in areas where the prevalence and intensity of Schistosoma haematobium infection is also high. Experimental evidence shows bladder carcinogenesis to be a multi-stage process which can be accelerated by many factors. N-nitroso compounds, some of which are known bladder carcinogens, can be formed from amine precursors and nitrate in urine during some bacterial infections. In experimental animals the growth of nitrosamine-induced urothelial cancers is accelerated by damage to the urothelium caused by S. haematobium infections, and by analogy in man this could account for the lower peak age of incidence of this cancer in Egypt by comparison with Europe.The present study was designed to investigate whether bacterial infection of the urinary tract was common in areas of endemic schistosomiasis and whether N-nitrosamines were regularly found to be associated with bacteriuria. Urine samples from young men in the Qalyub area of Egypt and from an adjacent Delta region were analysed for S. haematobium ova, the nature and intensity of any bacterial infection, nitrate and nitrite, and total N-nitroso compounds plus volatile N-nitrosamines. A relatively high prevalence of bacteriuria was found in young men with schistosomiasis and low levels of N-nitroso compounds were present in all specimens. When the groups were sub-divided on the basis of the ability of their bacterial flora to reduce nitrate to nitrite (the latter is required for the nitrosation of amine precursors to N-nitroso compounds), significantly higher levels of N-nitroso compounds were found in S. haematobium-infected individuals also infected with nitrate-reducing bacteria by comparison either with uninfected controls (p < 0 · 0005) or with those infected with non-nitrate-reducing bacteria (p <0 · 001).The results show N-nitroso compounds to be present in the urines of young men in areas of endemic S. haematobium infection in Egypt, and elevated levels of urinary N-nitroso compounds to be associated with infection of the urinary tract by various species of nitrate-reducing bacteria.     

Effect of myocardial reperfusion on the release of nitric oxide after regional ischemia: an experimental model of beating-heart surgery

Off-pump coronary artery bypass surgery is increasing in popularity worldwide. However, very little is known about the effect of regional myocardial ischemia-reperfusion on nitric oxide release. In an animal model mimicking off-pump bypass, male Sprague-Dawley rats (350-450 g) were mechanically ventilated under general anesthesia. After left lateral thoracotomy, the animals underwent occlusion of either the left anterior descending artery (for 3, 5, 75, 10, 12.5, 15, or 20 minutes) or the circumflex artery (for 5, 10, or 15 minutes). Twenty-four hours after reperfusion, heart tissue was stained for determination of the area at risk and the infarcted area. Blood samples obtained before ischemia, 10 minutes after reperfusion, and 24 hours after reperfusion were analyzed for plasma concentrations of nitric oxide. After occlusion of the left anterior descending artery, the size of the infarcted area increased dramatically as the duration of occlusion increased, and was significantly larger after 12.5, 15, or 20 minutes of occlusion than after 3 minutes. After occlusion of the circumflex artery, the size of the infarcted area increased steadily and was significantly larger after 15 minutes of occlusion than after 5 minutes. There was no significant correlation between the duration of coronary occlusion and the plasma concentration of nitric oxide: 10 minutes after reperfusion, this concentration was significantly lower than that before ischemia, but it was twice the baseline level 24 hours after reperfusion. We concluded that the duration of regional ischemia did not affect the plasma concentration of nitric oxide in the systemic circulation.