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J Savolainen

Publications and source records attributed to J Savolainen.

At least 37 records · Page 2Linked to original sources
PubMed2000

Synthesis of a water-soluble prodrug of entacapone.

Entacapone was reacted with phosphorous oxychloride in dry pyridine to yield a phosphate ester. The phosphate promoiety increased aqueous solubility of the parent drug by more than 1700- and 20-fold at pH 1.2 and 7.4, respectively. The phosphate ester provides adequate stability (t(1/2) = 2227 h; pH 7.4) towards chemical hydrolysis, and allowed for release of the parent drug via enzymatic hydrolysis in liver homogenate.

Catechol O-Methyltransferase Inhibitors↗
PubMed2000

Synthesis and in vitro/in vivo evaluation of novel oral N-alkyl- and N,N-dialkyl-carbamate esters of entacapone.

Entacapone has a relatively low oral bioavailability which may, in part, be due to its low aqueous solubility at low pH and/or its hydrophilic character at neutral pH. Various novel N-alkyl and N,N-dialkyl carbamate esters of entacapone were synthesized as possible prodrugs of entacapone in order to increase its aqueous solubility at an acidic pH and to increase its lipophilicity at neutral pH. Oral bioavailability of entacapone and selected carbamate esters were investigated in rats. Both N-alkyl and N,N-dialkyl carbamate esters were relatively stable against chemical hydrolysis at pH 7.4 (t1/2 = 14.9-20.7 h), but hydrolyzed rapidly (t1/2 = 0.8-2.7 h) in human serum. However, in contrast to N-alkyl carbamates, N,N-dialkyl carbamates did not release entacapone in in vitro enzymatic hydrolysis (human serum) studies. N-Alkyl carbamates, 2a-c, showed increased aqueous solubility at pH 7.4, of which 2a and 2c also show increased aqueous solubility at pH 5.0, compared to entacapone. In addition to increased aqueous solubility, 2c showed increased lipophilicity at pH 7.4. However, two N-alkyl carbamates of entacapone did not increase the oral bioavailability of the parent drug in rats. Thus, it can be concluded that the relatively low lipophilicity of entacapone is not the cause of its low bioavailability.

Absorption↗
PubMed2000

Uptake of the yeast Malassezia furfur and its allergenic components by human immature CD1a+ dendritic cells.

Atopic dermatitis (AD) is a chronic inflammatory skin disease with increasing prevalence, though still little is known of the pathomechanisms and the causes of the disease. Patients with AD often have specific IgE reactivity to the yeast Malassezia furfur (M. furfur), present in the normal microflora on human skin. To investigate the possible interaction of immature and mature antigen-presenting dendritic cells with the yeast M. furfur and its allergenic components. Monocyte-derived dendritic cells (MDDCs) generated from human peripheral blood were allowed to interact with FITC-labelled whole M. furfur yeast cells, M. furfur extract, a recombinant allergen from M. furfur designated rMal f 5 and M. furfur mannan, in the absence of IgE antibodies. Interaction and uptake were detected using flow cytometry and confocal laser scanning microscopy. Internalization of M. furfur yeast cells and yeast components by immature MDDCs was found using confocal laser scanning microscopy. Results from flow cytometric studies showed that a median of 94% (range, 65-98%) of the immature CD1a+ MDDCs were M. furfur extract positive, 81% (75-97%) rMal f 5 positive and 93% (62-98%) mannan positive. Mature CD1a+ MDDCs were significantly less efficient in this respect, with the corresponding figures only 26% (6-37%, P < 0.01), 6% (2-15%, P < 0.05) and 32% (9-50%, P < 0.01), respectively. Uptake of the non-glycosylated rMal f 5 by immature CD1a+ MDDCs was decreased to 27% (15-38%) by inhibition of pinocytosis. The binding of M. furfur extract and mannan was inhibited in a dose-dependent manner by methyl-alpha-D-mannopyranoside, suggesting uptake via the mannose receptor. Human immature CD1a+ MDDCs can efficiently take up M. furfur and allergenic components from the yeast in the absence of IgE antibodies, implying that sensitization of AD patients to M. furfur can be mediated by immature dendritic cells in the skin.

Allergens↗
PubMed1999

alpha-Chymotrypsin-catalyzed degradation of desmopressin (dDAVP): influence of pH, concentration and various cyclodextrins.

Desmopressin [1-(mercaptopropanoic acid)-8-D-arginine vasopressin; dDAVP] is a vasopressin analogue with a selective antidiuretic effect. The oral bioavailability of desmopressin is limited due both to its high hydrophilicity leading to a low intestinal permeability and to low enzymatic stability. The degradation of desmopressin was investigated in aqueous buffer solutions (pH 6.00-9.00) containing the enzyme alpha-chymotrypsin at a concentration of 0.50 mg/ml at 37 degrees C. The degradation of desmopressin was also studied in solutions containing alpha-chymotrypsin in the concentration range 0.10-1.00 mg/ml (pH 7.40 and 37 degrees C). The rate of degradation was shown to be highly dependent on both enzyme concentration and pH. Maximal alpha-chymotrypsin activity was observed in the pH range 7.40-8.00. It was observed that phenylalanine was formed during the degradation of desmopressin. Phenylalanine was formed in the amount of 20% in 120 min. In the same time period 95% of desmopressin was degraded. The formation of phenylalanine can be explained from the substrate specificity of alpha-chymotrypsin. Cyclodextrins are known to stabilize drugs including peptides against both chemical and enzymatic degradation. In this study it was shown that hydroxypropyl cyclodextrins (alpha, beta and gamma) stabilized desmopressin against alpha-chymotrypsin-catalyzed degradation. The stabilization was by a factor of 3, 9 and 8 at the concentration 12.5% (w/v) for hydroxypropyl-alpha-cyclodextrin, hydroxylpropyl-beta-cyclodextrin and hydroxypropyl-gamma-cyclodextrin.

Chymotrypsin↗
PubMed1999

Human isometric force production and electromyogram activity of knee extensor muscles in water and on dry land.

This study was designed to determine trial-to-trial and day-to-day reproducibility of isometric force and electromyogram activity (EMG) of the knee extensor muscles in water and on dry land as well as to make comparisons between the two training conditions in muscle activity and force production. A group of 20 healthy subjects (12 women and 8 men) were tested three times over 2 weeks. A measurement session consisted of recordings of maximal and submaximal isometric knee extension force with simultaneous recording of surface EMG from the vastus medialis, vastus lateralis and biceps femoris muscles. To ensure identical measurement conditions the same patient elevator chair was used in both the dry and the wet environment. Intraclass correlation coefficients (ICC) and coefficients of variation (CV) showed high trial-to-trial (ICC = 0.95-0.99, CV = 3.5%-11%) and day-to-day reproducibility (ICC=0.85-0.98, CV=11%-19%) for underwater and dry land measurements of force and EMG in each muscle during maximal contractions. The day-to-day reproducibility for submaximal contractions was similar. The interesting finding was that underwater EMG amplitude decreased significantly in each muscle during maximal (P < 0.01-P < 0.001) and submaximal contractions (P < 0.05-P < 0.001). However, the isometric force measurements showed similar values in both wet and dry conditions. The water had no disturbing effect on the electrodes as shown by slightly lowered interelectrode resistance values, the absence of artefacts and low noise levels of the EMG signals. It was concluded that underwater force and EMG measurements are highly reproducible. The significant decrease of underwater EMG could have electromechanical and/or neurophysiological explanations.

Adult↗
PubMed1999

Local reactions and IgE antibodies to pertussis toxin after acellular diphtheria-tetanus-pertussis immunization.

Local reactions and pertussis toxin specific immunoglobulin E antibodies (PT-IgE) were investigated in healthy children following primary and booster immunization with a combined diphtheria tetanus acellular pertussis vaccine (DTPa) including pertussis toxin, filamentous haemagglutinin and pertactin. A primary series of DTPa was administered to 150 infants, and 104 of them received a booster dose of DTPa combined with inactivated polio vaccine at 2 years of age. PT-IgE was measured in serum samples from 72 children using a modified nitrocellulose RAST. Primary immunization was associated with low incidence of local reactions (1%-5%). After the booster dose 21% of children had a local reaction >/=20 mm. Local reactions after the booster dose tended to be more common in children who had experienced reaction at primary immunization. PT-IgE was detected in 18% and 86% of children following primary and booster vaccinations, respectively. Allergic and non-allergic children did not differ in PT-IgE responses. After primary immunization, elevated PT-IgE levels were found more often in children with a family history of allergy than in those without known allergy in the family. Children with local reactions had significantly higher pre- and post-booster PT-IgE levels and median post-booster pertactin IgG and diphtheria-IgG levels than children without local reactions. Conclusion Acellular pertussis immunization induces IgE antibodies to pertussis toxin, especially after booster vaccination. The higher median pre- and post-booster levels of pertussis toxin specific immunoglobulin E and post-booster levels of IgG to pertactin and diphtheria in children with local side-effects reflect a multifactorial immunological mechanism of such reactions.

Child, Preschool↗
PubMed1999

Drug release from a porous ion-exchange membrane in vitro.

The effect of environmental ionic strength on the rate of drug release from a cation exchange membrane was evaluated. Cationic propranolol-HCl, timolol, sotalol-HCl, atenolol and dexmedetomidine-HCl and neutral diazepam were adsorbed onto a porous poly(vinylidene fluoride) (PVDF) membrane that was grafted with bioadhesive poly(acrylic acid) chains (PAA-PVDF). Despite its porosity, the PAA-PVDF membrane acted as a cation exchange membrane. The release of adsorbed drug from the PAA-PVDF membrane was investigated by using a USP rotating basket apparatus. Adsorption of cationic drugs onto the PAA-PVDF membrane tended to increase with increasing lipophilicity of the drug. A decrease in the ionic strength of the adsorption medium increased the amount of the cationic drugs adsorbed onto the membrane, but had no effect on diazepam adsorption. The release of cationic drugs from the PAA-PVDF membrane was greatly affected by the ionic strength of both the adsorption medium and the dissolution medium, while ionic strengths did not affect diazepam release. Our results suggest that the ionic strength of both the adsorption and dissolution media substantially affects the release rate of a drug that has been adsorbed onto the ion exchange membrane, primarily via electrostatic interactions, while ionic strength has no effect on the release of a drug which has been adsorbed onto the membrane via non-electrostatic forces.

Acrylic Resins↗
PubMed1999

Cross-reacting IgE and IgG antibodies to Pityrosporum ovale mannan and other yeasts in atopic dermatitis.

Atopic dermatitis (AD) patients often demonstrate positive skin prick test results and serum IgE antibodies to a range of different yeasts. This has been thought to be due to cross-reactivity. In this study, the cross-reactivity of IgE and IgG antibodies between mannan and crude antigens of Pityrosporum ovale, Candida albicans, and Saccharomyces cerevisiae and crude antigens of Cryptococcus albidus and Rhodotorula rubra was examined by RAST and ELISA inhibition with two serum pools of AD patients. We found cross-reacting IgE and IgG antibodies. In the IgE response, the main cross-reacting pattern was the mannan region, although inhibition could be achieved also with crude antigens of C. albicans, S. cerevisiae, and, to some extent, C. albidus. P. ovale was the most potent inhibitor of IgE-binding components, and against it the highest IgE antibody levels were detected in AD serum pools. In contrast, C. albicans was found to be the most important inducer of IgG antibodies, since the IgG level against P. ovale mannan in both AD serum pools was very low. Cross-reacting antibodies were also seen in ELISA inhibition with both crude and mannan antigens, but since the IgG antibody level of P. ovale mannan in AD serum pools was low, further studies are needed to confirm the IgG results.

Antibodies, Anti-Idiotypic↗
PubMed1999

Candida albicans mannan- and protein-induced humoral, cellular and cytokine responses in atopic dermatitis patients.

BACKGROUND: The cytokine observed most often in atopic dermatitis (AD) is IL-4, but a role for IL-5 and IFN-gamma in the late and delayed phase reactions has been suggested. In AD with head, neck and shoulder distribution, hypersensitivity to saprophytic yeasts is an important pathogenetic factor. The yeast allergens include both the mannan polysaccharides and the proteins. Mannans are major cross-reacting allergens likely to be involved in the pathogenesis of AD. OBJECTIVE: To characterize the humoral, lymphoproliferative and cytokine (IL-2, 4, 5 and IFN-gamma) responses of peripheral blood mononuclear cells (PBMCs) induced by Candida albicans mannan and protein antigens in AD. METHODS: Fifteen AD patients and seven healthy controls were included. Ficoll-isolated PBMCs were stimulated by PHA and laboratory-generated mannan and protein extracts of C. albicans. Lymphocyte proliferation was measured and cytokine production was studied by ELISA. The antigen-specific IgG and IgE antibodies were analysed by ELISA and nitrocellulose RAST. RESULTS: In AD mannan (P < 0.005) and protein (P < 0.002), specific IgE levels were higher than in healthy controls. Both mannan and protein-specific lymphoproliferations (both: P < 0.02) were higher in AD than in healthy controls. Mannan, but not protein, induced long lasting IL-2 and IL-4 productions from 24 h lasting up to 66-96 h and IL-5 and IFN-gamma productions with elevated levels at 66 and 96 h. The mannan-induced IL-2 (P = 0.015) and IFN-gamma (P < 0.005) were increased in AD as compared with healthy controls. Significant correlations were seen between the protein-induced proliferation responses and both serum total IgE (r = 0.59, P < 0.01) and protein-specific IgE (r = 0.65, P < 0.005). The mannan-induced IL-2 responses correlated with the specific IgE (r = 0.62, P < 0.01) and proliferation (r = 0.51, P < 0.02) and S-IgE level (r = 0.71, P < 0. 002). Mannan-induced IL-4 and IFN-gamma productions also correlated (r = 0.43, P < 0.05). CONCLUSIONS: C. albicans mannan induced elevated IL-2 and IFN-gamma responses in AD patients. The correlations of the cytokine responses with mannan-induced IgE and proliferation responses suggest that C. albicans mannan induced TH1 type cytokine responses are involved in AD.

Adult↗
PubMed1998

Muscle capillary supply in hind limb and diaphragm of the common shrew (Sorex araneus).

Shrew species of the subfamily Soricinae have unusually high metabolic rates when compared to Crocidurinae shrews and other similar-sized mammals. The aim of this study was to clarify whether the high basal metabolic rate of Soricinae shrews is reflected in a high capillary density in their muscles. To this end, the capillary supply of four limb muscles and diaphragm of the common shrew (Sorex araneus) was quantified from cross-sectioned muscles. The capillary densities of the limb muscles were 2575 +/- 329, 3111 +/- 299, 2812 +/- 197 and 2752 +/- 173 capillaries mm-2 fibre area in gastrocnemius lateralis, g. medialis, plantaris and soleus, respectively. Capillary density of the shrew diaphragm (6691 +/- 1057) was double that of the limb muscles. This value is among the highest ever measured in mammals. In general, the capillary supply in the hind limb of the common shrew is about 3-4 times higher than commonly found in the leg muscles of the laboratory rat or other bigger mammals, but similar to those in Crocidurinae shrews and some small rodents. Thus the high resting metabolism of the common shrew is not associated with an extraordinarily high capillary density. The apparent disparity between basal metabolic rate and muscle capillary supply in S. araneus is probably due to the small aerobic scope of shrews in the subfamily Soricinae.

Analysis of Variance↗
PubMed1998

The common cold: effects of intranasal fluticasone propionate treatment.

OBJECTIVE: A double-blind, randomized, placebo-controlled trial was conducted to study the effect of the intranasal corticosteroid, fluticasone propionate (FP), in the naturally occurring common cold. METHODS: One hundred ninety-nine young adults received high-dose FP (200 microg four times daily) or placebo beginning 24 to 48 hours after onset of the common cold for 6 days. All symptoms were recorded on diary cards on days 1 to 20, and clinical examinations were carried out on days 1, 7, and 21. Nasopharyngeal aspirates were collected on days 1 and 7 for detection of rhinoviruses (found in 105 subjects) and Streptococcus pneumoniae, Haemophilus influenzae, or Moraxella catarrhalis (found in 52 subjects) in the nasopharynx. RESULTS: In general, FP treatment had no clinically recognizable effects on the symptoms of the common cold, although it significantly reduced nasal congestion and cough on some study days. After treatment, rhinoviruses were cultured more often in the FP treatment group (37% vs 14%, p < 0.001), but this had no effect on the symptoms of common cold. FP treatment produced no changes in the colonization of pathogenic bacteria in the nasopharynx. Some symptoms of common cold were significantly more severe during days 1 to 10 (p < 0.05) in subjects found to have positive cultures for S. pneumoniae, H. influenzae, or M. catarrhalis in the nasopharynx on day 1 (n = 33). CONCLUSION: FP treatment does not have any marked effects on the symptoms of the common cold. FP treatment induced prolonged shedding of viable rhinoviruses. Some symptoms of the common cold were significantly more severe in subjects with pathogenic bacteria in the nasopharynx.

Administration, Intranasal↗
PubMed1998

Co-administration of a water-soluble polymer increases the usefulness of cyclodextrins in solid oral dosage forms.

PURPOSE: The aim of this study was to investigate the effect of cyclodextrins (beta-CD, HP-beta-CD and (SBE)7m-beta-CD), and co-administration of a water-soluble polymer (HPMC) and cyclodextrins, on the oral bioavailability of glibenclamide in dogs. METHODS: Effects of cyclodextrins on the aqueous solubility of glibenclamide, with and without hydroxypropylmethylcellulose (HPMC), were determined by a phase-solubility method. Solid inclusion complexes were prepared by freeze-drying. Glibenclamide was administered orally and intravenously to beagle dogs. RESULTS: Aqueous solubility of glibenclamide increased as a function of cyclodextrin concentration, showing an AL-type diagram for beta-CD and an Ap-type diagrams for both of the beta-CD derivatives studied. HPMC enhanced the solubilising effect of cyclodextrins, but did not affect the type of phase-solubility diagram. Orally administered glibenclamide and its physical mixture with HP-beta-CD showed poor absolute bioavailability, while orally administered glibenclamide/cyclodextrin-complexes significantly enhanced the absolute bioavailability of glibenclamide. Orally administered glibenclamide/beta-CD/HPMC and glibenclamide/(SBE)7m-beta-CD/HPMC complexes showed similar absolute bioavailability compared to formulations not containing HPMC, even though 80% (in the case of (SBE)7m-beta-CD) or 40% (in the case of beta-CD) less cyclodextrin was used. CONCLUSIONS: The oral bioavailability of glibenclamide was significantly increased by cyclodextrin complexation. HPMC increased the solubilising effect of cyclodextrins and, therefore, the amount of cyclodextrin needed in the solid dosage form was significantly reduced by their co-administration. In conclusion, the pharmaceutical usefulness of cyclodextrins in oral administration may be substantially improved by co-administration of a water-soluble polymer.

Administration, Oral↗
PubMed1998

Stability of Pityrosporum ovale allergens during storage.

BACKGROUND: Pityrosporum ovale is a common saprophyte on the skin capable to induce IgE antibody production in atopic dermatitis. Generally IgE response to P. ovale has been established with skin-prick test, but the stability of P. ovale skin test allergens is not known. OBJECTIVE AND METHODS: In this study we analysed the stability of identified allergens of P. ovale in skin test solutions during storage. The stability was checked with immunoblotting and densitometry after different time periods and at various temperatures. RESULTS: Coomassie Brilliant blue staining clearly showed, that proteins were preserved poorly at + 20 degrees C in 50% glycerol. Even extracts stored at + 4 degrees C during 6 and 12 months in 50% glycerol were degraded. Only extract stored at + 4 degrees C for 1 month in 50% glycerol was quite well preserved. According to densitometry results the 9 kDa band was the most stable main protein allergen. The 20 kDa and especially the 96 kDa bands were far more labile. The stability of low molecular allergens was in general better than the stability of high molecular weight allergens. CONCLUSIONS: The stability of P. ovale extracts stored for more than 1 month was poor even when kept at + 4 degrees C temperature. Reliability of negative skin prick results should be questioned when older extracts are used. In skin test negative cases, the sensitization should be evaluated also with the measurement of specific serum IgE antibodies to P. ovale.

Allergens↗
PubMed1998

Genetic and environmental factors affecting the allergenicity of birch (Betula pubescens ssp. czerepanovii [Orl.] Hämet-ahti) pollen.

BACKGROUND: Environmental variation, such as an increase of mean temperature due to the greenhouse effect, as well as the genetic factors may affect the allergenicity of pollen and thus, the prevalence of allergies. The connection between these factors and the allergen content of pollen is poorly understood. OBJECTIVES: To evaluate the role of environmental and genetic factors on the allergenicity of birch pollen. METHODS: Mountain birch (Betula pubescens ssp. czerepanovii (Orl.) Hämet-Ahti) pollen was studied using SDS-PAGE and IgE-immunoblotting. Pollen samples were collected from the trees of 10 half-sib families. The study trees from each family were reared in two tree line gardens where the daily mean temperatures were different during the growing season. RESULTS: The quantitative analysis of band intensities suggested that the responses of the major birch pollen allergen, Bet v 1, were stronger in the samples collected from the garden with higher daily mean temperature. Half-sib families and individual trees differed in their Bet v 1 content. CONCLUSIONS: Our results show that both genetic and environmental factors have an effect on the amount of Bet v 1. This suggests that breeding for trees low in allergen content may be possible.

Allergens↗
PubMed1998

In-house reference (IHR) preparation of Candida albicans allergen extract. A standardized extraction procedure.

A standardized, controlled procedure for preparation of an in-house reference (IHR) preparation of an allergen extract of Candida albicans is described. The procedure, based on previous studies of allergens of C. albicans, is designed to yield a maximum of allergens in optimum extraction conditions and to provide a reference preparation for further extract production. The SDS-PAGE, IgE-immunoblotting, and crossed radioimmunoelectrophoresis (CRIE) analyses showed that the procedure is reproducible with acceptable batch-to-batch variation. The variation in the content of the most important allergens, namely, proteins with molecular weights of 46, 29, and 27 kDa in the pooled final batches, is acceptable (coeff. of variation < 15%), although in the intermediate batches of different strains, the coefficient of variation may occasionally exceed 20%. A comparison with other C. albicans allergen preparations used in our previous studies is also presented. The resulting extract can be used as a reference in further extract production and also in experimental in vitro and in vivo studies.

Allergens↗
PubMed1998

IgE, IgA, and IgG responses to common yeasts in atopic patients.

This study was undertaken to analyze the differences in exposure and sensitization to five common environmental yeasts. The responses of IgG, IgA, and IgE to Candida albicans, C. utilis, Cryptococcus albidus, Rhodotorula rubra, and Saccharomyces cerevisiae and purified S. cerevisiae enolase were analyzed by immunoblotting (IgE-IB), and the cross-reactivity of their IgE-binding components by IgE-IB inhibition. Twenty atopic subjects, with asthma, allergic rhinitis, or atopic dermatitis were included. In skin prick tests (SPT), 12 of the patients showed simultaneous reactivity to at least two of the five yeasts, four reacted to one of the yeasts, and four had no responses. Antigens run in SDS-PAGE and transferred to nitrocellulose were probed with enzyme-labeled IgA-, IgG-, and IgE-specific antibodies. The IgE immunoblotting revealed most IgE-binding bands in C. albicans (11 bands) followed by C. utilis (eight bands), S. cerevisiae (five bands), R. rubra (five bands), and Cr. albidus (four bands). Six of the IgE-binding bands of C. albicans and C. utilis shared molecular weight, and only two bands shared molecular weight with other yeasts. These were the 46-kDa band, shared by all five yeasts, and a 13-kDa band shared by four yeasts. Prominent IgE binding was seen to a 46-kDa band of C. albicans (seven patients), C. utilis (five patients), and S. cerevisiae (one patient) and to corresponding weak bands of Cr. albidus and R. rubra (one patient). The possible cross-reactivity of the 46-kDa band was analyzed by IgE-IB inhibition and densitometry, revealing clear C. albicans inhibition of C. utilis (80%) and enolase (98%) (autoinhibition 100%). The strongest IgG responses were seen against S. cerevisiae and C. albicans. The responses were mainly against mannans of C. albicans and S. cerevisiae, suggesting that most of the exposure is to these yeasts. Yeasts with different types of exposure, from saprophytic growth on human mucous membranes to exposure by air and food, were shown to cross-react at the allergenic level. Atopic patients primarily sensitized by C. albicans and S. cerevisiae may develop allergic symptoms by exposure to other environmental yeasts due to cross-reacting IgE antibodies.

Adolescent↗