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Biomedical subjects

E Bengtsson

Publications and source records attributed to E Bengtsson.

At least 91 records · Page 5Linked to original sources
PubMed1979

Habits of malaria chemoprophylaxis and an analysis of breakdowns in a West African mining town.

In a West African community approximately 80% of the non-African personnel were taking malaria prophylactics in the recommended manner. The non-takers stated that they were afraid of side-effects of the drugs and/or under-estimated the risks of the disease. During one year 123 patients with clinically suspected malaria were studied. All patients with positive slides were cured with regular dose of 1.5 g chloroquine base. No chloroquine resistance was therefore demonstrated, although 4-aminoquinoline prophylaxis had been given for almost 20 years to thousands of non-African non-immunes as well as in pregnant women and children in the town. Common reasons for 'breakdowns' were febrile disease other than malaria, false positive diagnosis and improper chemoprophylaxis.

Chloroquine↗
PubMed1979

The concentration of chloroquine in serum during short and long term malaria prophylaxis with standard and 'double' dosage in non-immunes: clinical implications.

The concentration of chloroquine in serum was analysed after one week, six weeks and one year on standard dose prophylaxis (300 mg chloroquine base once a week) and after six months on the double dose. After six weeks, the standard dose gave adequate protection against malaria. During the first weeks of prophylaxis insufficient protection might be achieved by the customary standard dose. In a double-dose group many values reached the point above which a higher incidence of side-reactions have been observed.

Adult↗
PubMed1979

Analysis of reproducibility of subjective grading systems for breast carcinoma.

The inter- and intra-observer reproducibility of three grading systems for breast cancer has been analysed: those of the World Health Organisation, of Black, and of Hartveit. In addition, the components forming the basis of these grading systems were analysed separately with regard to reproducibility and interrelationship. In this analysis, degree of differentiation was also included as a parameter. The grading systems of WHO and of Black gave a stratification of the material into three categories of tumours, but that of Hartveit did not. All three systems had a low inter- and intra-observer reproducibility. Truncated component analysis indicated that the grading systems of WHO and of Black are closely related to each other and to the 'nuclear lobulation' component of Hartveit's system. The components 'pleomorphism', 'mitotic frequency', and 'hyperchromasia' of the WHO system were closely interrelated. Descriptors such as 'differentiation' and 'tubule formation' were interrelated but acted in a different direction from the others.

Breast Neoplasms↗
PubMed1979

High resolution segmentation of cervical cells.

A major problem in the automation of cervical cytology screening is the segmentation of cell images. This paper presents the present status of the work on that problem at the University of Uppsala. A dual resolution system is used. Suspect malignant cells are located at 4 mu resolution. Each such cell is rescanned at 0.5 mu resolution at two different wavelengths, 530 and 570 nm. The nucleus and the cytoplasm are isolated each by two independent methods. For the nucleus adaptive thresholding in the histogram of the 570 nm image and a contouring in a radially transformed version of that image is used. For the cytoplasm a two dimensional thresholding in the 2D histogram and a contouring in a radially transformed version of the 530 nm image is used. If the two nuclear masks agree the surrounding area is checked for disturbing objects. If also the cytoplasm masks agree and are without disturbing objects the whole cell is accepted. The result of the cytoplasm masks agree and are without disturbing objects the whole cell is accepted. The result of the segmentation is thus three categories; free cells, free nuclei and rejected objects. The shape of the objects belonging to the former two categories is checked and irregularly shaped ones are rejected as probably consisting of several overlapping nuclei. Cells passing also this test are classified as normal or malignant. The experience from using this algorithm is discussed and areas for further research are pointed out.

Cell Nucleus↗
PubMed1979

Antibodies to Rift Valley fever virus in Swedish U.N. soldiers in Egypt and the Sinai.

Swedish United Nations Emergency Forces soldiers serving in Egypt and the Sinai peninsula were serologically tested for hemagglutination-inhibiting antibodies to Rift Valley fever (RVF) virus. Eight of 170 were positive. RVF has not been reported outside Africa, and a survey of 500 Swedish soldiers who had not served in the Middle East or Africa revealed no RVF virus antibodies. There were extensive RVF epidemics in Egypt in 1977 and 1978, and it is considered that these serologically positive soldiers contracted RVF disease while on duty in the Middle East.

Adult↗
PubMed1978

Computer analysis of cervical cells. Automatic feature extraction and classification.

A prescreening instrument for cervical smears using computerized image processing and pattern recognition techniques requires that single cells in the specimen can be automatically isolated and analyzed. This paper describes a dual wavelength method for automatic isolation of the cytoplasm and nuclei of cells. Density-oriented, shape-oriented and texture-oriented parameters were calculated and evaluated for more than 600 cells. It is shown that the computer can be taught to distinguish between normal and atypical cells with an accuracy of ca. 97%, while human classification reproducibility is ca. 95%. In addition, an attempt to assign a measure of atypia to individual cells is described.

Cell Nucleus↗
PubMed1978

Serum Q fever antibodies in Swedish UN soldiers in Cyprus--reflecting a domestic or foreign disease?

Swedish soldiers from 2 battalions serving in Cyprus 1975 and 1976 were tested serologically for Coxiella burnetii phase 2 complement-fixing antibodies. 2.7% were positive. Although none of the seropositive soldiers had been seriously ill abroad, the titers are considered to emanate from an infection in Cyprus as there is no evidence of domestic Q fever from a survey of 1390 Swedes.

Antibodies, Bacterial↗
PubMed1978

Computerized nuclear morphometry as an objective method for characterizing human cancer cell populations.

A new method for measuring differences in nuclear detail in chrome alum gallocyanin-stained nuclei of cells from human breast cancers was compared with conventional subjective grading and classification systems. The new method, termed computerized nuclear morphometry (CNM), gives a multivariate numerical score that correlates well with nuclear atypia and gives a higher reproducibility of classification than do subjective observations with conventional histological preparations. When 100 individual nuclei from each of 137 breast cancers were examined by CNM, there was a broad CNM score variation between patients but a good reproducibility for each tumor. When different parts of the same tumor were sampled, there was good reproducibility between samples, indicating that some breast cancers at least are "geometrically monoclonal." When these cancers were compared by the grading systems of WHO and Black, correlations of 0.43 and 0.48, respectively, were found. There was a poor correlation between CNM and classifications of tumor type, but in general there were high values for CNM in medullary tumors and low values in mucous tumors. Correlations between CNM and tumor progression and prognosis await future study of patients participating in the study.

Breast Neoplasms↗
PubMed1977

Q fever and animal abortion in Cyprus.

Seventy-eight British soldiers stationed in the Eastern Sovereign Base Area (ESBA) in Cyprus contracted Q fever in the period December 1974 to June 1975. Pneumonia developed in 59% of cases. Of 31 patients tested, 81% had biochemical evidence of hepatitis although only one became clinically jaundiced. Three patients (4%) suffered pericarditis. Treatment with tetracycline had no apparent effect on the course of the disease. Investigation revealed an abortion epidemic involving 21 mixed flocks of sheep and goats in the south-eastern coastal region. 11 of the flocks grazed in and around the ESBA. A serological survey of 10 affected flocks, and evidence collected from previous years, indicated that the abortion epidemic was the result of infection with Coxiella burneti. Infection in the humans was almost certainly acquired by inhalation of dust from brush contaminated with rickettsial parturition products of the aborting flocks. A human serological survey revealed a number of cases of subclinical Q fever in a susceptivle military population, and an asymptomatic epidemic in a largely immune local position.

Abortion, Veterinary↗
PubMed1977

The effect of experimental uveitis on the uptake of prostaglandin E1 in the rabbit iris-ciliary body.

Disruption of the blood-aqueous barrier in rabbits was elicited by infrared irradiation of the iris or by alpha-melanocyte stimulating hormone (alpha-MSH) given subcutaneously. One group of animals was pretreated with topical imidazole before the injection of alpha-MSH. The aqueous flare response was followed and the rabbits were killed at the expected height of the uveitis. The uptake of 3H-prostaglandin E1 in the iris with the ciliary body was then determined and found to be significantly decreased in the rabbits in which alpha-MSH had caused a severe damage of the blood-aqueous barrier. When alpha-MSH caused a more moderate aqueous flare response the prostaglandin uptake was on the contrary significantly increased. Pretreatment of the animals with topical imidazole enhanced parallelly the prostaglandin uptake and the aqueous flare response to alpha-MSH. Topical imidazole per se was found to increase the accumulation of prostaglandin. The prostaglandin uptake values were, however, unchanged in eyes in which infrared irradiation of the iris induced a moderate flare response.

Administration, Topical↗
PubMed1977

The effect of polyphloretin phosphate on the aqueous flare response to alpha-melanocyte stimulating hormone.

The breakdown of the blood aqueous barrier caused by topical prostaglandin E1 (PGE1), prostaglandin E2 (PGE2) or subcutaneous alpha-melanocyte stimulating hormone (alpha-MSH) was quantified by measurements of the aqueous flare seen in the anterior chamber. Polyphloretin phosphate (PPP) administration subcutaneously was found to effectively block the protein leakage caused by all three traumatic stimuli. The same dose of PPP given intravenously inhibited effectively the flare response to PGE1 and alpha-MSH, whereas the effect of PGE2 was only slightly decreased. Significant inhibition by subconjunctival PPP was not achieved for any of the three stimuli. Assuming that PPP is a specific PG-antagonist the present results support the eariler suggestion that PGs take part in the barrier damaging action of alpha-MSH. However, it cannot be excluded that PPP acts on a step subsequent to PG. This step might be common to PGs- and alpha-MSH-effects on the barrier, explaining why PPP inhibits both types of trauma.

Administration, Topical↗
PubMed1977

A program system for interactive measurements on digitized cell images.

Using a high precision image scanner and a PDP-8/F minicomputer, we have developed a program system for interactive measurements on microscopic images. By giving simple keyboard commands, the operator can run the image scanner and manipulate the digitized images. The interface between the operator and the microscope-computer system is a Tektronix 4010 graphic terminal. The system allows objects to be isolated and parameters to be calculated from each object, e.g., parameters characterizing shape of the object, irregularity in light transmission over the object, area, integrated light transmission, etc. Objects are isolated and parameters are calculated under complete operator control using interactive computer graphics technique. Calculated parameters may be stored in dedicated data records, which are stored in files for later statistical analysis. The system also includes a statistical evaluation part. Technically, the system consists of a command scanner, which translates commands into internal representation, a parser, which checks the syntax of the commands, and an interpreter, which executes the commands. The system is designed so that new commands can be added easily.

Computers↗