Search PubMed⌕ Search

Biomedical subjects

M Koskinen

Publications and source records attributed to M Koskinen.

At least 73 records · Page 4Linked to original sources
PubMed1986

Long-term anticonvulsant therapy and vitamin D metabolism in ambulatory pubertal children.

Parameters of calcium metabolism were thoroughly examined in 28 adolescents with long-term (over 6 years) anticonvulsant therapy (phenytoin, carbamazepine or combination) and in 10 normal controls in September and in March. The adolescents did not receive any vitamin D supplementation during the study. Serum calcium, inorganic phosphorus, parathyroid hormone and alkaline phosphatase levels in the anticonvulsant group did not differ from those of the control group. Serum 25(OH)D and 24,25(OH)2D levels were in all groups consistently higher in September than in March, but no seasonal variation was found in the 1,25(OH)2D levels in any group. The serum 25(OH)D levels in the phenytoin group in March were the lowest among the three groups treated with anticonvulsants, but the levels in the anticonvulsant groups did not differ significantly from each other or from the control group in the same season. The 24,25(OH)2D and 1,25(OH)2D levels in the anticonvulsant groups did not differ significantly from those of control group in September or in March. There was no correlation between anticonvulsant serum free fraction levels and vitamin D metabolites. The bone mineral content in the distal radius was not significantly decreased in the epileptic patients. In conclusion, the long-term anticonvulsant therapy did not induce the so-called "anticonvulsant rickets" in this ambulatory adolescent material. Our data do not indicate that anticonvulsant drugs alter significantly the vitamin D metabolism. Thus, routine vitamin D supplementation does not appear to be indicated in children on anticonvulsant therapy.

Adolescent↗
PubMed1985

The use of radiolabelled monoclonal antibodies to human milk fat globule membrane antigens in antibody-guided tumour imaging, and administration of therapeutic dose of labelled antibody in wide-spread ovarian carcinoma. A preliminary report.

Monoclonal antibodies generated against human milk fat globule membrane antigens were used in antibody-guided tumour imaging and palliative therapy in a case of wide-spread ovarian carcinoma. Antibody III H 2, which previously has been shown to react with 100% of ovarian cystadenocarcinomas showed a strong reactivity with tissue sections obtained from the primary and metastatic tumours of the patient. Immunoglobulins were purified from mouse ascitic fluid containing III H 2 and labelled with 123I or 131I with the iodogen method. 80 MBq (2 mCi) of 123I-labelled antibody was given intraperitoneally in 500 ml of PBS and the uptake of radiolabel was followed daily with emission tomography. Radiolabel was mainly located in the peritoneal cavity; only a very low activity was seen in the thyroid gland and urinary bladder. A therapeutic dose consisting of 600 MBq (15 mCi) of 131I-labelled antibody was followed nine days later and the localization of the antibody was followed.

Antibodies, Monoclonal↗
PubMed1984

Caries prevention in rats by fluoride varnish treatment combined with addition of fluoride to dietary sugar.

Osborne-Mendel rats were fed a cariogenic diet containing 43% sucrose for 48 days. The control group received no additional treatment. The teeth of the second group received topical treatment with a sodium fluoride varnish which was applied twice onto newly-erupted molars. The third group received topical treatment with the sodium fluoride varnish combined with a NaF + Mg addition to the diet. In both treatment groups, caries was significantly reduced as compared with caries in the control group. Combined treatment was significantly more effective than was the varnish alone. In spite of the high fluoride concentration in the varnish, no changes in the oral mucosa were found at the end of the study.

Animals↗
PubMed1984

Effect of chlorhexidine-fluoride applications without and with Sr and Zn on caries, plaque, and gingiva in rats.

Molar teeth of four groups of Osborne-Mendel rats, kept on a cariogenic diet, were treated once per day for 48 days with either distilled water (solution C), a solution containing 0.05% chlorhexidine gluconate and 0.04% NaF, pH 5.8 (solution CXF), CXF plus 1000 ppm Sr (solution CXFS), or CXFS plus 1000 ppm Zn (solution CXFSZ). Caries of the hemi-sectioned lower molars was scored according to grades of severity, and the extent of the buccal plaque was estimated. Inflammatory cell infiltration, vascularity, and thickness of the oral mucosa were estimated from stained sections of the buccal oral mucosa to detect possible adverse effects of the treatments. Fissure caries lesions with involvement of the dentin were reduced by 57% (p less than 0.01) with the CXF treatment and by 68% (p less than 0.001) with the CXFS treatment. The CXFSZ treatment reduced the fissure caries least (44%, p less than 0.05), but it appreciably reduced the extent of plaque. The mucosal changes were greatest in the group receiving the CXFSZ treatment, but they were generally small and at a non-pathological level. Supplementation of the CXF solution with Sr thus appeared beneficial for caries reduction.

Animals↗
PubMed1984

Reduction of the lethality and the nephrocalcinotic effect of single fluoride doses by magnesium in rats.

Magnesium chloride, administered by gavage to fasting young rats, 30 min prior to sodium fluoride, elevated the LD50 for fluoride from 76 to 104 mg/kg body wt. The LD50 was elevated to greater than 180 mg/kg when magnesium was given in a dose equivalent to 2 or 3 times that of fluoride. In two experiments, a dose of 50 mg F/kg caused a mean 14- and 19-fold increase above the level of the control animals in the renal calcium content. The nephrocalcinotic effect of fluoride was nearly completely prevented by administering magnesium in a dose which is 3-fold the equivalent of the fluoride dose 30 min prior to fluoride.

Animals↗
PubMed1983

Arrestment of caries in rats by adding fluoride and magnesium to the diet.

90 weanling Osborne-Mendel rats were divided into six groups of 15 animals each. Half of them received a modified MIT 200 control diet in which one third of the sucrose of the original formula was replaced by high-extraction wheat fluor, magnesium content reduced to 360 parts/10(6) and phosphorus content increased NaH2PO4 . 2H2O to 0.49%. For the experimental diet, an additive containing 75 parts/10(6) fluoride as (NaF) and 50 parts/10(6) magnesium (as MgO) was mixed into the above composition. Each diet was given to three experimental or three control groups for 25, 40, or 55 d. Caries involving dentin-enamel junction was significantly reduced through the F+Mg addition by 37%, 51%, and 61% on the 25th, 40th, and 55th day, respectively. Caries involving dentin was significantly reduced by 58%, 68%, and 70%, respectively. Caries arrestment was observable in both the control rats and rats fed the F rMg additive but in the latter animals the reduction meant an arrestment at a lower level than in controls. This arrestment resembles an early caries arrestment obtained recently in a clinical trial by fluoridation of dietary sugar products. The growth of the animals was only temporarily retarded by the additives.

Animals↗
PubMed1982

Caries reduction in rats through F + Mg supplementation of dietary sucrose with observations on bone mineral density and soft and hard tissue minerals.

Two control diets with different sucrose contents (44% and 22%) were given to weanling rats for 55 d. The test diets were supplemented with an F + Mg combination, 75 parts/10(6) F as NaF + 50 parts/10(6) Mg as MgO and 38 parts/10(6) F + 25 parts/10(6) Mg, respectively, i.e. using the same supplement/sucrose ratio in each test diet. The supplementation in each test diet caused the same percentage fissure caries reduction, but the absolute mean caries scores were higher in the high-sucrose groups than in the respective low-sucrose groups. Enamel solubility was reduced by the supplementation. Despite the high fluoride supplementation, no untoward effects were recorded in growth and in aortic, heart, and renal calcium contents. Bone mineral density was reduced in the low-sucrose controls and slightly reduced in the high-sucrose F + Mg supplemented rats, as compared with the high-sucrose controls.

Animals↗
PubMed1982

Screening of bacteria in urine using luciferin-luciferase assay of microbial ATP: a comparative study.

A total of 3227 urine specimens were analysed to investigate the applicability of a firefly luciferase assay of microbial adenosine triphosphate (ATP) for the rapid screening of bacteriuria in clinical specimens. Urine sediment, dipslide culture, and three plate cultures were also investigated in the majority of the urine specimens, the plate cultures serving as the reference. Of the specimens with positive plate culture (greater than or equal to 10(5) colony forming units (CFU)), leucocyte content of the spun urine sediment was negative (less than or equal to 4 cells per high-power field) in 34% and bacterial content was negative in 14% (no bacteria seen microscopically); the dipslide test was negative (less than 10(5) CFU) in 16%, and the luminescence assay of ATP in 7% (less than or equal to 500 relative light units). Of the urine specimens forming less than 10(5) CFU on plate cultures, leucocytes were positive in 15%, spun sediment bacteria in 21%, the dipslide test in 0.5%, and the luminescence assay of ATP in 11%. When used as a screening test for further studies by complete culture techniques, the luminescence assay of microbial ATP can improve the rapid diagnosis of urinary tract infections.

Adenosine Triphosphate↗
PubMed1981

Serial measurements of quantitative EEG and cerebral blood flow and circulation time after brain infarction.

The quantitative EEG (QEEG), regional cerebral blood flow (rCBF) and circulation time of 17 patients were examined semisimultaneously thrice during the first 3 months after a cerebral supratentorial infarction. The EEG was quantified according to normalized slope descriptor technique in nine patients and by means of a combined period and amplitude analysis in eight patients. Intravenously injected isotopes 133Xenon and 99TcmO4 were used for blood flow and circulation time measurements. The QEEG-values improved during the whole follow-up period. Cerebral blood flow stayed low for all 3 months and did not alter during this period, while initially prolonged circulation time to some extent improved within 2 weeks remaining, however, prolonged even thereafter. A tendency for a positive correlation between QEEG and rCBF values in the infarcted hemisphere could be seen.

Adult↗
PubMed1981

Renal blood flow in high and low positions of aortal catheter in rabbits.

The effect of aortal catheterization on renal blood flow (RBF) was evaluated in seven rabbits weighing 2500 to 3500 g. RBF was measured 21 times from 13 kidneys during aortal catheterization with an isotope (133 Xe) technique. The catheter was positioned in the aorta of each rabbit both above and below the origins of the renal arteries. The results of these two measurements were compared. Two phases of RBF, a fast first phase and a slow second phase, were determined. The fast phase of RBF was 5.3 ml/g/min, when it was in the high position. The results of the slow phase were identical, 0.16 ml/g/min, in both positions. No significant statistical difference could be found according to the phase of the catheter (paired t-test). These results in rabbits suggest that the aortal catheter does not cause any immediate decrease in RBF. This finding has clinical importance in aortal catheterization in neonates to obtain arterial blood samples. When considering the position of the aortal catheter in neonates factors other than RBF should be taken into account.

Animals↗
PubMed1980

Use of the modulation transfer function in comparing the visual outcome units of gamma camera.

Modulation transfer function (MTF) was used in comparing the visual outcome units of gamma camera. Polaroid camera system and Micro Dot imager were studied using Polaroid film type 105 positive/negative and Kodak SO-179 X-ray film. It was proved that resolution in the Micro Dot imager is better than in the Polaroid camera system used, especially near the surface of the measuring object.

Gamma Rays↗
PubMed1980

Evaluation of cerebral infarctions of the carotid area by an intravenous 133Xenon and 99mTechnetium method.

Quantitative determinations of regional cerebral blood flow (rCBFf, rCBFm) and volume (rCBV), transfer time (rCTT) and fast compartmental weight (Wf) were performed in 34 patients with infarctions of the carotid area by a 133Xe and 99mTc intravenous injection method. The results were compared with clinical signs and electroencephalographic (EEG) findings. A significant difference was found between the lesion side and the control side in all the parameters except rCBV. This difference increased with the severity of the infarction and age of the patients. The difference between the two sides was especially great in the patients with totally occluded internal carotid artery. A slight diaschisis could be observed in the present infarction group. An almost significant reduction on the "normal side" was seen in Wf. In order to assess the reciprocal influence of all the different blood flow parameters, the difference index (DI): Formula: (see text) was calculated, where delta i = the difference between the two sides in one parameter expressed in percent. This proved to be abnormal in 80% of the patients. The atraumatic isotope technique employed offers a good opportunity for the quantitative evaluation of hemodynamics in cerebral infarction and serves as an aid in the diagnosis of infarction.

Adult↗
PubMed1980

Left ventricular function after dynamic and static exercise in ischaemic heart disease.

The effects of dynamic and static exercise on left ventricular function in ischaemic heart disease were studied in 20 patients with angiographically documented coronary artery disease. Radiocardiography was used to determine left ventricular volumes at rest and during exercise tests. Dynamic exercise increased cardiac output significantly (p less than 0.001) in the 10 patients with one-vessel coronary artery disease, whereas end-diastolic and end-systolic volume and ejection fraction did not change from the resting values. In contrast, in the 10 patients with multiple coronary vessel disease significant increases in end-diastolic (p less than 0.05) and end-systolic volumes (p less than 0.001) were observed during dynamic exercise. Cardiac output increased by only 21% (p less than 0.05) while a decrease in ejection fraction (p less than 0.005) reflected pump dysfunction in these patients. Static exercise did not change cardiac output or end-diastolic volume significantly. The end-systolic volumes increased in both patient groups, more so in the patients with multi-vessel coronary involvement (p less than 0.005 and p less than 0.01, respectively). These data revealed a different left ventricular volume response to dynamic exercise in the patients with one-vessel coronary artery disease compared with those with multi-coronary involvement. The afterload stress taking place during the static exercise, on the other hand, evoked left ventricular dysfunction very sensitively and similarly, irrespective of the extent of coronary artery stenoses.

Adult↗
PubMed1980

Cardiovascular responses to static and dynamic effort three weeks after myocardial infarction.

Left ventricular responses to dynamic and static exercises were compared in 20 patients three weeks after myocardial infarction. Radiocardiography was used to determine the ventricular volumes at rest and during hand grip and bicycle exercise tests. The dynamic exercise increased cardiac output (p less than 0.001), and the end-diastolic volume of the left ventricle increased (p less than 0.005) from the resting value while the ejection fraction decreased (p less than 0.005). Static hand grip exertion did not increase cardiac output or the end-diastolic volume. Decrease of the stroke volume and the ejection fraction (p less than 0.001 both) again reflected pump dysfunction during the afterload stress. Our data revealed that patients with recent myocardial infarction had a range of ventricular responses to dynamic exercise. Poor response in the ejection fraction was noted in anterior infarction and in those patients using digoxin and/or diuretics after infarction. During static exercise, on the other hand, impairment of cardiac performance was constant, irrespective of the site of infarction. Reduction of the ejection fraction was greater during static exercise in the patients receiving digoxin and/or diuretics than in those not taking these drugs.

Adult↗