FPGA Implementation of Heart Rate Monitoring System.

This paper describes a field programmable gate array (FPGA) implementation of a system that calculates the heart rate from Electrocardiogram (ECG) signal. After heart rate calculation, tachycardia, bradycardia or normal heart rate can easily be detected. ECG is a diagnosis tool routinely used to access the electrical activities and muscular function of the heart. Heart rate is calculated by detecting the R peaks from the ECG signal. To provide a portable and the continuous heart rate monitoring system for patients using ECG, needs a dedicated hardware. FPGA provides easy testability, allows faster implementation and verification option for implementing a new design. We have proposed a five-stage based methodology by using basic VHDL blocks like addition, multiplication and data conversion (real to the fixed point and vice-versa). Our proposed heart rate calculation (R-peak detection) method has been validated, using 48 first channel ECG records of the MIT-BIH arrhythmia database. It shows an accuracy of 99.84%, the sensitivity of 99.94% and the positive predictive value of 99.89%. Our proposed method outperforms other well-known methods in case of pathological ECG signals and successfully implemented in FPGA.

Abnormalities of the erythrocyte membrane in chronic myelogenous leukemia.

Chronic myelogenous leukemia (CML) is a hematologic malignancy characterized by excessive growth of myeloid cells and their progenitors. The proportion of spectrin dimers compared to tetramers extracted from membranes at 4 degrees C, under low ionic strength conditions, increased in CML erythrocytes. These also displayed abnormal thermal sensitivity (between 45 and 46 instead of 49 degrees C). Crosslinking with the bifunctional reagent, dimethyl adipimidate (8.6 A) showed significant organizational modification of not only spectrin, but other cytoskeletal components such as ankyrin, bands 4.2 and 5. Enhanced concanavalin A (Con-A) agglutinability of CML erythrocytes also suggests altered topographic distribution of a functionally important membrane protein, band 3. The anion transport activities of erythrocytes from patients with CML and normal donors were comparable. In CML erythrocytes, significant reduction in the number of ankyrin-binding sites, present in the cytoplasmic domain of band 3, may lead to partial loss of cytoskeletal anchorage to the bilayer and account for their increased Con-A agglutinability and heat sensitivity and may lead to their premature removal from the circulation.

Abnormalities in erythrocyte membrane band 3 in chronic myelogenous leukemia.

The anion transport activities of erythrocytes from patients with chronic myelogenous leukemia (CML) and normal donors were comparable. In CML erythrocytes, significant reduction in the number of ankyrin-binding sites, present in the cytoplasmic domain of band 3, may lead to partial loss of cytoskeletal anchorage to the bilayer and account for their increased Con-A agglutinability and heat-sensitivity (Basu, J., Kundu, M., Rakshit, M.M. and Chakrabarti, P. (1988) Biochim. Biophys. Acta 945, 121-126).

Abnormalities in the erythrocyte membrane in acute lymphoid leukaemia.

Erythrocytes from patients suffering from acute lymphoid leukaemia (ALL) show decreased proportions of spectrin tetrameters and altered spatial distribution of band 4.1 and ankyrins. These abnormalities of the cytoskeleton are probably responsible for altered membrane fluidity and transbilayer distribution of phosphatidylethanolamine in ALL. ALL is associated with severe anaemia and usually, but not always, with overproduction of lymphocytes. To our knowledge, this is the first report of abnormalities in the erythrocyte membrane in ALL which may, in part, be responsible for the observed anaemia.

Abnormal erythrocyte membrane cytoskeleton structure in chronic myelogenous leukaemia.

Chronic myelogenous leukaemia (CML) is a haematologic malignancy characterised by excessive growth of myeloid cells and their progenitors. Our studies show that there are several abnormalities in CML red blood cells. The proportion of spectrin dimers compared to tetramers extracted from membranes at 4 degrees C, under low ionic strength conditions, increased in CML erythrocytes. These also displayed abnormal thermal sensitivity (between 45 and 46 instead of 49 degrees C). Decreased spectrin tetramer formation observed in several hereditary anaemias has been associated with decreased red cell deformability leading to splenic sequestration. This could also be one of the causes of the severe anaemia observed in CML. Crosslinking with the bifunctional reagent, dimethyl adipimidate (8.6 A) showed significant organizational modification of not only spectrin, but other cytoskeletal components such as ankyrin, bands 4.2 and 5. Enhanced concanavalin A agglutinability of CML erythrocytes also suggests altered topographic distribution of a functionally important membrane protein, band 3.

Epidemiology of sarcoidosis in the Isle of Man--1: A case controlled study.

A case controlled study of 96 cases of sarcoidosis has been carried out in the Isle of Man. Age and sex matched controls were selected at random from the pathology and radiology records, which cover 85% of the resident population, and a second control group was drawn from a tuberculosis register. Special efforts were made to achieve a high level of ascertainment. In this study most cases occurred in young adults. It affected the sexes equally and occurred more frequently in the indigenous Manx population. Thirty eight cases (39.6%) had been in contact with the disease before diagnosis, compared with two (1.2%) of the combined controls. These contacts included members of the same household, colleagues at work, and close friends. A bias may have been introduced as patients would inevitably be more aware of the disease and be more likely to mention previous contact than the controls. Nevertheless, the evidence is considered to support the view that sarcoidosis is a communicable disease.

Incidence of sarcoidosis in the Isle of Man.

The incidence of sarcoidosis in a clearly defined island community has been determined in a seven year study. Special efforts were made to identify all cases, including those presenting to their general practitioners with only minor symptoms. A mean incidence of 14.7 per 100 000 per annum has been found in the years 1977-83 compared with an annual incidence of 3.5 per 100 000 in the preceding 15 years, when no specific attempts were made to identify sufferers from sarcoidosis. The lower figure is similar to the reported incidence in the United Kingdom and the difference is considered to be due to increased detection of cases during the study period. These findings suggest that a large proportion of cases of sarcoidosis in a general population may not be recorded in a registration system.

Psittacosis in the elderly.

Six elderly patients with serological evidence of psittacosis but atypical syndromes are described. These cases illustrate the difficulties in diagnosing this infection in the old. Four patients were febrile and three had lesions visible on X-ray of the chest. Three died, in one acute toxic viral myocarditis seemed the cause. All were treated with tetracycline, which must be given generously. Psittacosis infection would probably be more commonly diagnosed in the old if serological examinations were carried out in old people immediately on their administration to hospital because of a severe febrile illness. Serological tests appear clearly to be the most certain means of identifying psittacosis in patients with multiple pathology.