The origin of Staphylococcus saprophyticus from cattle and pigs.

Staphylococcus saprophyticus is a common cause of urinary tract infections. We have earlier shown that the bacterium is a contaminant of food of animal origin. In order to trace the natural reservoir of the bacterium, samples were taken from farming environment and from slaughtered carcasses. S. saprophyticus was found in 7.1% of rectal swabs from cattle carcasses and in 7.3% of rectal swabs from slaughtered pigs. The seasonal variation of these isolates paralleled the seasonality of urinary tract infections due to the same bacterium. S. saprophyticus was also isolated in 1.1% of rectal swabs from living cows, in 1.6% from pasture grass and from 12.4% of various indoor fodder. The fodder presented a seasonal distribution with a peak incidence of S. saprophyticus some months earlier than in rectal swabs. The bacterium was especially frequent in samples of fodder taken from the managers. S. saprophyticus is most likely a bacterium with a zoonotic origin.

Urinary tract infections caused by Staphylococcus saprophyticus. A matched case control study.

Epidemiological and clinical aspects of 270 episodes of urinary tract infection caused by Staphylococcus saprophyticus were studied. The cases were randomly selected and matched consecutively with 276 others of urinary tract infection according to sex, age and temporal occurrence. Such infections were found typically among young women in the outpatient health service. They were common among professionals handling meat products and were especially associated with prior outdoor swimming. Common symptoms of inflammation of the lower urinary tract, haematuria and pyuria were seen more often among patients with S. saprophyticus infections. Some cases of asymptomatic S. saprophyticus infection, however, were seen. We found S. saprophyticus as the cause of 13% upper urinary tract infections, an incidence which is higher than has been reported for other bacteria. Staphylococcus saprophyticus was less correlated to nephrolithiasis and was not a common cause of catheter-induced infections.

Plasmid-identified Staphylococcus saprophyticus isolated from the rectum of patients with urinary tract infections.

Among 15 strains of Staphylococcus saprophyticus of various origin, 13 presented different plasmid patterns, making plasmid identification a useful epidemiological marker. In a consecutive study of 14 young female patients with urinary tract infection caused by S. saprophyticus, 6 patients were simultaneously positive for the same bacterium in the stools. Three paired samples contained the identical plasmid-identified clone of S. saprophyticus indicating that the rectum may be a reservoir of this urinary pathogen.

Staphylococcus saprophyticus found to be a common contaminant of food.

The mode of transmission of Staphylococcus saprophyticus, a urinary tract pathogen, was investigated in three related studies. The presence of this organism was sought, during a period of 1 year, in 1331 specimens of various foods, in 920 beef and pork carcasses and on 107 cultures which had been inoculated directly from abattoir workers' protective gloves. Staphylococcus saprophyticus was found to contaminate 16.4% of the various food samples with a high prevalence of 34% in raw beef and pork. It was common in both domestic and imported raw meat products. There was no seasonal variation in the presence of S. saprophyticus in the samples obtained from carcasses. The bacterium was found in 69% of all cultures from the workers' protective gloves. We conclude that S. saprophyticus, originating from slaughtered animals, contaminates food and eventually colonizes the human intestinal tract.

Monthly antimalarial chemotherapy to children in a holoendemic area of Liberia.

Two hundred and eighty-two children, two to nine years old, were included in a prospective three-year study in four villages with holoendemic malaria. In three villages the children received monthly doses of either chloroquine, pyrimethamine or chlorproguanil respectively for two years. In the fourth, vitamin tablets were used as placebo. Presumptive treatment with chloroquine (10 mg base kg-1) was given to all children with fever of suspected malarial origin. The two-year drug distribution was satisfactorily fulfilled to 168 children. Surveys, including physical and laboratory examinations were performed every six months, four weeks after medication. A fifth village was only visited at the start of the study and after two years. The mean crude parasite rate was initially 92%. Plasmodium falciparum was the main species. Splenomegaly was recorded in all children. In the chloroquine-treated children, the parasite rates varied between 30% and 50% during the study. By the end of the second year the spleen rate was reduced from 100% to 50%. Reported episodes of fever were reduced to half and mean haematocrit levels increased by 6% in comparison with children receiving the placebo. Total IgG concentrations were reduced from 36.7 g l-1 to 25.9 g l-1, whereas no significant decrease was observed in malarial seropositivity as measured by indirect immunofluorescence. Chlorproguanil had a weaker impact on parasitaemia with parasite rates between 50% and 90%. However, the spleen rate was reduced to 67% and there was a significant reduction of reported fever episodes. Mean haematocrits increased by 4%. Total IgG decreased from 31.8 g l-1 to 23.8 g l-1. In contrast, in the pyrimethamine group, the placebo group and the untreated group from the fifth village, the malariometric indices after two years were comparable to each other and to the initial values. During the third year only presumptive chloroquine treatment was given, and by the end of the study all malariometric indices were again comparable. From clinical observations there was no apparent impairment of protective immunity to malaria from the two years of regular distribution of the drugs. We conclude that a certain degree of malaria control could be achieved in Liberian children by the administration of monthly doses of chloroquine 10 mg base kg-1. The administration of chlorproguanil (1.5 mg kg-1) represents an alternative regimen.

Sensitivity in vivo of Plasmodium falciparum to chloroquine and pyrimethamine/sulfadoxine in a coastal area of Tanzania.

The in vivo response of Plasmodium falciparum to chloroquine and to pyrimethamine/sulfadoxine was studied for seven days in schoolchildren from two villages 30 to 40 km north of Dar es Salaam. Standard therapeutic regimen of chloroquine (25 mg base kg-1) failed to clear parasitaemia in 17 of 62 (27%) treated subjects. In contrast, standard treatment with pyrimethamine/sulfadoxine cleared the parasitaemia in all 44 treated subjects within five days. Hence, in the studied area, the therapeutic effect of sulfadoxine/pyrimethamine was superior to that of chloroquine.

Monitoring of protein product formation during fermentation with fast protein liquid chromatography.

A method is described using fast protein liquid chromatography (FPLC) for the monitoring of protein formation during fermentation. The procedure consists of centrifugation to recover the cells, sonication of the cells, centrifugation to remove cell debris, and analysis of supernatant on a column of Mono Q (a strong anion exchanger). Analysis of peak areas provides quantitative determination of product concentration. Maintenance and life of the Mono Q column is discussed. We find that FPLC is a convenient method for measuring products in cell homogenates because it gives rapid, highly resolved separations.

Malaria control by chlorproguanil. I. Clinical effects and susceptibility of Plasmodium falciparum in vivo after seven years of monthly chlorproguanil administration to children in a Liberian village.

For seven years, chlorproguanil (1.0 to 2.0 mg kg-1) was administered monthly to the children below 15 years of age in a village with holoendemic malaria. Malariometric indices were recorded every six months. Susceptibility in vivo was monitored by the clearance of Plasmodium falciparum parasitaemia after drug intake. Three parasite species were found initially: P. falciparum (52%), P. malariae (8%) and P. ovale (4%). The parasites found during the study were mainly P. falciparum, and parasite rates ranged from 37 to 87% at the different surveys one month after respective drug intake. A fifty-fold decrease of mean parasite density was generally observed seven days after drug intake. Splenomegaly was initially recorded in all two to nine year old children, with a mean size of 2.64 according to Hackett's index. From 18 months onwards as the mean spleen index was 1.15 in the same age group. Chlorproguanil may represent an important alternative drug to groups at risk in malaria control schemes.

Different malaria control activities in an area of Liberia--effects on malariometric parameters.

The epidemiology of malaria was studied in a West African mining town (Yekepa) and three surrounding zones defined as Close, Middle and Far areas. Malariometric parameters were investigated in children two to nine years of age at the end of the rainy season. In Yekepa, vector control measures and intense suppression of malaria with drugs had created an almost hypoendemic situation with a spleen rate of 11%. In Close area, vector control was applied to some extent and malaria drugs were frequently used for treatment; the spleen rate was 40%. In Middle area, a mobile clinic provided sporadic malaria treatment to small children, but the clinic did not reach out to Far area. The spleen rates were 95 and 99%, respectively. Three species of Plasmodium were found in all areas. The prevalences in Far area were P. falciparum 82%, P. malariae 39% and P. ovale 9%. The crude parasite rates increased from 13% in Yekepa to 92% in Far area, whereas haematocrit levels decreased from 37.6 to 35.2, respectively. Plasmodium falciparum seropositivity, as measured by indirect immunofluorescence, was 74% in Yekepa and 99% in Middle and Far areas. Total IgG concentrations ranged from 18 g1(-1) in Yekepa to 33 g1(-1) in Far area. Three main anopheline species were found in the zones outside Yekepa. Their relative frequencies in Far area were Anopheles funestus 45%, A. hancocki 37%, and A. gambiae 18%. The local inoculation rates gradually increased outwards from Yekepa from less than 0.01 to 0.17 inoculations per man and night at the beginning of the dry season.(ABSTRACT TRUNCATED AT 250 WORDS)

Reduction of proteolytic breakdown in microbial homogenates.

Proteolytic enzymes are present in many biological raw materials used for the production of proteins and peptides. Such enzymes are active not only in homogenates of bacteria and yeast but also in ascites liquid and cell culture media used for the production of monoclonals. A new protease substrate was used to determine protease activity in homogenates of E. coli and baker's yeast, which are useful for the production of therapeutically valuable polypeptides. Using this substrate we found that cooling and the addition of protease inhibitors had little effect on the proteolytic activity. Most of the proteolytic activity however could be adsorbed to hydrophobic gel media. Data is given on the protease adsorption at different temperatures and ionic strengths.

Protein adsorbents intended for use in aqueous two-phase systems.

Preparation of adsorbents with high partition coefficients in polyethylene glycol-dextran and polyethylene glycol-phosphate systems is described. These adsorbents may be used to carry to carry proteins away from the insoluble cell fragments generated during cell disruption. By chromatographic elution, proteins may be selectively desorbed in a reduced volume.

Serum concentrations of chloroquine in a patient with a late recrudescence of Kenyan Plasmodium falciparum malaria.

A Swedish tourist who had visited Kenya fell ill with Plasmodium falciparum malaria 11 days after returning home, in spite of taking pyrimethamine (50 mg weekly) as malaria prophylaxis. Chloroquine treatment (25 mg base/kg body-weight) giving serum concentrations of 0.30 mumol/l cleared the patent parasitaemia and the patient recovered. Recrudescence occurred, however, within 42 days. A second chloroquine course (30 mg base/kg) gave serum levels up to 1.28 mumol/l. The patient improved rapidly and remained healthy during 28 days without renewed parasitaemia. Further follow-up for 10 months was uneventful. We consider it urgent to assess chloroquine concentrations in serum in patients being treated for falciparum malaria in order to obtain data on fully effective levels. Ineffective serum levels should be ruled out in cases not responding to chloroquine, especially when chloroquine-resistance is suspected.

A pocket of controlled malaria in a holoendemic region of West Africa.

Yekepa, a mining town in northern Liberia, has been built entirely since 1960 and now has a population of 16 000 inhabitants including 1500 expatriates. Although situated in a holoendemic region with constant human movements in and out of the town, the mining company has succeeded in controlling malaria in Yekepa. Furthermore, there is a constant threat of the vector in the close surroundings to the town. Control is maintained by regular residual insecticide sprayings with DDT, regular larviciding with fuel oil and fortnightly issue of amodiaquine chemoprophylactic to all workers. A Malariometric survey showed that the spleen and parasite rates were 11% and 13% respectively in the controlled areas and 95% and 67% respectively in surrounding regions not subjected to control measures. The dominant malaria parasite in the area was Plasmodium falciparum. No adult vectors were found in the town. In the surrounding villages the average room density of adult vectors was 3.8 and the sporozoite rate in a village very close to the town was 9.2%. The dominant vector of the area was Anopheles gambiae with A. Funestusalso being present. The annual per capita cost, including all control activities, is about 4--5 US dollars.