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Parikka P, Hakala K, Tiilikkala K. Expected shifts inFusariumspecies’ composition on cereal grain in Northern Europe due to climatic change. Food Addit Contam Part A Chem Anal Control Expo Risk Assess 2012; 29:1543-55. [DOI: 10.1080/19440049.2012.680613] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Rahi M, Heikkinen T, Hakkola J, Hakala K, Wallerman O, Wadelius M, Wadelius C, Laine K. Influence of adenosine triphosphate and ABCB1 (MDR1) genotype on the P-glycoprotein-dependent transfer of saquinavir in the dually perfused human placenta. Hum Exp Toxicol 2008; 27:65-71. [PMID: 18480151 DOI: 10.1177/0960327108088971] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND The ATP-dependent drug-efflux pump, P-glycoprotein (P-gp) encoded by ABCB1 (MDR1), plays a crucial role in several tissues forming blood-tissue barriers. Absence of a normally functioning P-gp can lead to a highly increased tissue penetration of a number of clinically important drugs. METHODS We have studied the dose-response effect of exogenous ATP on the placental transfer of the well-established P-gp substrate saquinavir in 17 dually perfused human term placentas. We have also studied the influence of the ABCB1 polymorphisms 2677G>T/A and 3435C>T on placental P-gp expression (n = 44) and the transfer (n = 16) of saquinavir. RESULTS The present results indicate that the addition of exogenous ATP to the perfusion medium does not affect the function of P-gp as measured by saquinavir transfer across the human placenta. The variant allele 3435T was associated with significantly higher placental P-gp expression than the wild-type alleles. However, neither polymorphism affected placental transfer of saquinavir nor there was any correlation between P-gp expression and saquinavir transfer. CONCLUSIONS Our results indicate that addition of exogenous ATP is not required for ATP-dependent transporter function in a dually perfused human placenta. Although the ABCB1 polymorphism 3435C>T altered the expression levels of P-gp in the human placenta, this did not have any consequences on P-gp-mediated placental transfer of saquinavir.
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Affiliation(s)
- M Rahi
- Department of Pharmacology, Drug development and Therapeutics, University of Turku, Turku, Finland.
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Rahi M, Heikkinen T, Härtter S, Hakkola J, Hakala K, Wallerman O, Wadelius M, Wadelius C, Laine K. Placental transfer of quetiapine in relation to P-glycoprotein activity. J Psychopharmacol 2007; 21:751-6. [PMID: 17259208 DOI: 10.1177/0269881106074065] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Atypical antipsychotic drugs are well tolerated and thus often preferred in women of fertile age; yet the information on their placental transfer and use during the prenatal period is limited. The aim of this study was to study the placental transfer of quetiapine, a widely used atypical antipsychotic, with special reference to the role of the placental transporter protein, P-glycoprotein (P-gp). This was performed in 18 dually perfused placentas, using the well established P-gp inhibitors PSC833 (valspodar) and GG918 to inhibit the function of P-gp. We also aimed to clarify the significance of two potentially functional ABCB1 single nuclear polymorphisms (SNPs), 2677G>T/A and 3435C>T, on the transplacental transfer (TPT) of quetiapine. The placental transfer of quetiapine in the control group as measured by TPT(AUC) % (absolute fraction of the dose crossing placenta) was 3.7%, which is 29% less than the transfer of the freely diffusible antipyrine, which was 5.2%. The P-gp inhibitors had no significant effect on the transfer of quetiapine as measured by TPT(AUC) % (P = 0.77). No correlation was found between the transplacental transfer of quetiapine (TPT(AUC) %) and placental P-gp expression (P = 0.61). The 3435T allele in exon 26 was associated with significantly higher placental transfer of quetiapine (P = 0.04). We conclude that quetiapine passes the human placenta but that the blood-placental barrier partially limits the transplacental transfer of quetiapine. Administration of P-gp inhibiting drugs with quetiapine is not likely to increase fetal exposure to quetiapine, although the ABCB1 C3435T polymorphism may contribute to inter-individual variation in fetal exposure to quetiapine.
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Affiliation(s)
- Melissa Rahi
- Department of Pharmacology and Clinical Pharmacology, Joint Clinical Biochemistry Laboratory of University of Turku, Turku University Central Hospital, Turku, Finland.
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Florea-Wang D, Ijäs I, Hakala K, Mattinen J, Vilpo J, Hovinen J. Reactions of {4-[Bis(2-chloroethyl)amino]phenyl}acetic Acid (Phenylacetic Acid Mustard) with 2′-Deoxyribonucleosides. Chem Biodivers 2007; 4:406-23. [PMID: 17372943 DOI: 10.1002/cbdv.200790033] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Phenylacetic acid mustard (PAM; 2), a major metabolite of the anticancer agent chlorambucil (CLB; 1), was allowed to react with 2'-deoxyadenosine (dA), 2'-deoxyguanosine (dG), 2'-deoxycytidine (dC), 2'-deoxy-5-methylcytidine (dMeC), and thymidine (T) at physiological pH (cacodylic acid, 50% base). The reactions were followed by HPLC and analyzed by HPLC/MS and/or (1)H-NMR techniques. Although the predominant reaction observed was hydrolysis of PAM, 2 also reacted with various heteroatoms of the nucleosides to give a series of products: compounds 5-31. PAM (2) was found to be hydrolytically slightly more stable than CLB (1). The principal reaction sites of 2 with dA, dG, and with all pyrimidine nucleosides were N(1), N(7), and N(3), resp. Also, several other adducts were detected and characterized. There was no significant difference in the reactivity of 1 and 2 with dG, dA or T, but the N(3) dC-PAM adduct was deaminated easier than the corresponding CLB derivative. The role of PAM-2'-deoxyribonucleoside adducts on the cytotoxic and mutagenic properties of CLB (1) is discussed.
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Snapir A, Posti J, Kentala E, Koskenvuo J, Sundell J, Tuunanen H, Hakala K, Scheinin H, Knuuti J, Scheinin M. Effects of low and high plasma concentrations of dexmedetomidine on myocardial perfusion and cardiac function in healthy male subjects. Anesthesiology 2006; 105:902-10; quiz 1069-70. [PMID: 17065883 DOI: 10.1097/00000542-200611000-00010] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Dexmedetomidine, a selective alpha2-adrenoceptor agonist, has counteracting effects on the cardiovascular system. It mediates sympatholysis by activating alpha2 adrenoceptors in the central and peripheral nervous system, and vasoconstriction and vasorelaxation by activating postsynaptic alpha2 adrenoceptors in blood vessels. The goal of this study was to determine the effects of therapeutic and high concentrations of dexmedetomidine on myocardial perfusion and cardiac function in healthy subjects. METHODS The authors studied 12 healthy young men. Myocardial blood flow (assessed with positron emission tomography), myocardial function (by echocardiography), and hemodynamic data were collected before and during low (measured mean plasma concentration, 0.5 ng/ml) and high (5 ng/ml) plasma concentrations of dexmedetomidine. RESULTS The low concentration of dexmedetomidine reduced myocardial perfusion (mean difference, -27% from baseline [95% confidence interval, -31 to -23%], P < 0.001) in parallel with a reduction in myocardial oxygen demand (estimated by the rate-pressure product (-23% [-28 to -18%], P < 0.001). The high dexmedetomidine plasma concentration did not further attenuate myocardial perfusion (-3% [-12 to +6%] from low dexmedetomidine, P > 0.05; -29% [-39 to -18%] from baseline, P < 0.001) or statistically significantly affect the rate-pressure product (+5% [0 to +10%], P > 0.05). Systolic myocardial function was attenuated by sympatholysis during the low infusion rate and was further attenuated by a combination of the sustained sympatholysis and increased afterload during the high infusion rate. CONCLUSIONS In healthy subjects, plasma concentrations of dexmedetomidine that significantly exceed the recommended therapeutic level do not seriously attenuate myocardial perfusion below the level that is observed with usual therapeutic concentrations and do not induce evident myocardial ischemia.
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Affiliation(s)
- Amir Snapir
- Department of Pharmacology, Drug Development and Therapeutics, University of Turku, Itäinen Pitkäkatu 4B, FI-20520 Turku, Finland.
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Smeds AI, Hakala K, Hurmerinta TT, Kortela L, Saarinen NM, Mäkelä SI. Determination of plant and enterolignans in human serum by high-performance liquid chromatography with tandem mass spectrometric detection. J Pharm Biomed Anal 2006; 41:898-905. [PMID: 16460900 DOI: 10.1016/j.jpba.2005.12.036] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2005] [Revised: 12/16/2005] [Accepted: 12/26/2005] [Indexed: 11/17/2022]
Abstract
An HPLC-MS/MS method was validated for the determination of the plant lignans 7-hydroxymatairesinol (HMR), matairesinol (Mat), secoisolariciresinol (Seco), lariciresinol (Lar), and cyclolariciresinol (CLar) and for the enterolignans 7-hydroxyenterolactone (HEL), enterodiol (ED), and enterolactone (EL) in human serum. The method included sample enzymatic hydrolysis, solid-phase extraction, and lignan analysis using a triple quadrupole mass spectrometer with electrospray ionisation in the multiple-reaction monitoring mode. The serum lignans were quantified using deuterated Mat or EL as internal standards. The method met the validation criteria for selectivity, intra- and inter-assay precision, and accuracy. The method was applied to ten serum samples collected from healthy individuals (five men and five women) consuming their habitual Finnish diet. All lignans except HMR and Seco were found in quantifiable amounts in the samples. All serums contained EL; the average concentration was 34 nM. In three individuals, the serum concentration of plant lignans was higher than that of enterolignans. Using the method, common dietary plant lignans and their major metabolites can be reliably quantified in human serum at low-nanomolar concentrations in a simple and rapid way.
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Affiliation(s)
- Annika I Smeds
- Abo Akademi University, Department of Organic Chemistry, Biskopsgatan 8, FI-20500 Turku, Finland.
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Kiljunen S, Hakala K, Pinta E, Huttunen S, Pluta P, Gador A, Lönnberg H, Skurnik M. Yersiniophage phiR1-37 is a tailed bacteriophage having a 270 kb DNA genome with thymidine replaced by deoxyuridine. Microbiology (Reading) 2006; 151:4093-4102. [PMID: 16339954 DOI: 10.1099/mic.0.28265-0] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Bacteriophage piR1-37 was isolated based on its ability to infect strain YeO3-R1, a virulence-plasmid-cured O antigen-negative derivative of Yersinia enterocolitica serotype O : 3. In this study, the phage receptor was found to be a structure in the outer core hexasaccharide of Y. enterocolitica O : 3 LPS. The phage receptor was present in the outer core of strains of many other Y. enterocolitica serotypes, but also in some Yersinia intermedia strains. Surprisingly, the receptor structure resided in the O antigen of Yersinia pseudotuberculosis O : 9. Electron microscopy demonstrated that phiR1-37 particles have an icosahedral head of 88 nm, a short neck of 10 nm, a long contractile tail of 236 nm, and tail fibres of at least 86 nm. This implies that the phage belongs to the order Caudovirales and the family Myoviridae in the ICTV (International Committee for Taxonomy of Viruses) classification. phiR1-37 was found to have a lytic life cycle, with eclipse and latent periods of 40 and 50 min, respectively, and a burst size of approximately 80 p.f.u. per infected cell. Restriction digestions and PFGE showed that the phiR1-37 genome was dsDNA and approximately 270 kb in size. Enzymically hydrolysed DNA was subjected to HPLC-MS/MS analysis, which demonstrated that the phiR1-37 genome is composed of DNA in which thymidine (T) is >99 % replaced by deoxyuridine (dU). The only organisms known to have similar DNA are the Bacillus subtilis-specific bacteriophages PBS1 and PBS2. N-terminal amino acid sequences of four major structural proteins did not show any similarity to (viral) protein sequences in databases, indicating that close relatives of phiR1-37 have not yet been characterized. Genes for two of the structural proteins, p24 and p46, were identified from the partially sequenced phiR1-37 genome.
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Affiliation(s)
- Saija Kiljunen
- Department of Bacteriology and Immunology, Haartman Institute, University of Helsinki and Helsinki University Central Hospital Laboratory, Helsinki, Finland
- Department of Medical Biochemistry and Molecular Biology, Institute of Biomedicine, University of Turku, Turku, Finland
| | - Kristo Hakala
- Department of Pharmacology and Clinical Pharmacology, Institute of Biomedicine, University of Turku, Turku, Finland
- Department of Chemistry, University of Turku, Turku, Finland
| | - Elise Pinta
- Department of Bacteriology and Immunology, Haartman Institute, University of Helsinki and Helsinki University Central Hospital Laboratory, Helsinki, Finland
- Department of Medical Biochemistry and Molecular Biology, Institute of Biomedicine, University of Turku, Turku, Finland
| | - Suvi Huttunen
- Department of Medical Biochemistry and Molecular Biology, Institute of Biomedicine, University of Turku, Turku, Finland
| | - Patrycja Pluta
- Department of Medical Biochemistry and Molecular Biology, Institute of Biomedicine, University of Turku, Turku, Finland
| | - Aneta Gador
- Department of Medical Biochemistry and Molecular Biology, Institute of Biomedicine, University of Turku, Turku, Finland
| | - Harri Lönnberg
- Department of Chemistry, University of Turku, Turku, Finland
| | - Mikael Skurnik
- Department of Bacteriology and Immunology, Haartman Institute, University of Helsinki and Helsinki University Central Hospital Laboratory, Helsinki, Finland
- Department of Medical Biochemistry and Molecular Biology, Institute of Biomedicine, University of Turku, Turku, Finland
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Abstract
OBJECTIVE Increased concentrations of proinflammatory cytokines in amniotic fluid indicate the presence of intra-amniotic inflammation and increase the risk of preterm birth, cerebral palsy, and bronchopulmonary dysplasia. The purpose of this study was to find out if the proinflammatory cytokines, tumor necrosis factor alpha (TNF-alpha), interleukin (IL)-1beta, and IL-6, transfer across the placenta, and thereby determine whether intra-amniotic inflammatory response, measured from the amniotic fluid, is of maternal or fetal origin. METHODS Nineteen placentas from healthy women undergoing elective cesarean delivery at term with intact membranes and without labor, were dually perfused ex vivo in an open circulation system for either 30 minutes or 2 hours. Tumor necrosis factor-alpha, IL-1beta, and IL-6 were added to maternal or fetal circulation in a concentration usually found in chorioamnionitis. As a reference, placentas without added cytokine were also perfused. The concentrations of cytokines were determined by enzyme immunoassays (enzyme-linked immunosorbent assay [ELISA]). RESULTS After the addition of the cytokine to the arterial perfusate, the venous concentration on the same side of the placenta increased rapidly and reached a plateau at 10 minutes. No transfer of any cytokine in either direction was detected. Some endogenous release of IL-6 was observed in response to the perfusion. CONCLUSION Proinflammatory cytokines do not cross normal term placenta.
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Affiliation(s)
- Riikka Aaltonen
- Department of Obstetrics and Gynecology and the Department of Clinical Pharmacology, Turku University Hospital, Turku, Finland.
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Mölsä M, Heikkinen T, Hakkola J, Hakala K, Wallerman O, Wadelius M, Wadelius C, Laine K. Functional role of P-glycoprotein in the human blood-placental barrier. Clin Pharmacol Ther 2005; 78:123-31. [PMID: 16084847 DOI: 10.1016/j.clpt.2005.04.014] [Citation(s) in RCA: 101] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2005] [Accepted: 05/03/2005] [Indexed: 11/28/2022]
Abstract
OBJECTIVE In vitro and animal experiments suggest that P-glycoprotein forms a functional barrier between maternal and fetal blood circulation in the placenta, thus protecting the fetus from exposure to xenobiotics during pregnancy. In this study we aimed to characterize the role of P-glycoprotein in the blood-placental barrier by use of dually perfused human placenta. METHODS Twenty-eight human placentas were obtained after delivery, and both the maternal side and the fetal side were perfused for 2 hours. Saquinavir was used as a probe drug for P-glycoprotein-dependent active transfer, and PSC833 (valspodar) or GG918 was used as an inhibitor of P-glycoprotein function in a maternal-to-fetal and fetal-to-maternal perfusion setting. Genotyping for ABCB1 (C3435T and G2677A/T) polymorphism and quantification of P-glycoprotein expression were done for each placenta. RESULTS The fetal-to-maternal transfer of saquinavir was 108-fold higher (P = .003) compared with transfer from the maternal to the fetal direction. Preperfusion with PSC833 increased the placental transfer of saquinavir by 7.9-fold (P < .001), and preperfusion with GG918 increased it by 6.2-fold (P < .001). The end-perfusion transfer (percentage) of saquinavir at 120 minutes was 11-fold (P < .001) and 6-fold (P < .001) higher in placentas preperfused with PSC833 and GG918, respectively, compared with control. However, PSC833 had no effect on the transfer of saquinavir from the fetal to the maternal direction (P = .79). P-glycoprotein expression was correlated with the PSC833-induced change in the saquinavir transfer (r = 0.75, P = .086). ABCB1 polymorphism did not affect the PSC833- or GG918-induced change in the saquinavir transfer. CONCLUSIONS P-glycoprotein has a major functional role in the human blood-placental barrier but a negligible role in the removal of substances from the fetal circulation to maternal blood. Pharmacologic blockade of P-glycoprotein function can lead to disruption of the blood-placental barrier and increase the transfer of P-glycoprotein substrates to the fetal side by several-fold, which may be a noteworthy mechanism for teratogenicity.
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Affiliation(s)
- Melissa Mölsä
- Department of Pharmacology and Clinical Pharmacology, University of Turku, Finland
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Ozdogan UK, Lähdesmäki J, Hakala K, Scheinin M. The involvement of alpha 2A-adrenoceptors in morphine analgesia, tolerance and withdrawal in mice. Eur J Pharmacol 2005; 497:161-71. [PMID: 15306201 DOI: 10.1016/j.ejphar.2004.06.051] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2004] [Revised: 06/24/2004] [Accepted: 06/25/2004] [Indexed: 11/16/2022]
Abstract
Alpha(2)-adrenoceptor agonists potentiate opioid analgesia and alleviate opioid withdrawal. The effects of two alpha(2)-adrenoceptor agonists, clonidine (2 mg/kg) and dexmedetomidine (20 and 100 microg/kg), and the alpha(1)-adrenoceptor antagonist prazosin (0.5 mg/kg) were tested on morphine analgesia, tolerance, and withdrawal in wild-type and alpha(2A)-adrenoceptor knock-out (KO) mice. Analgesia and tolerance were assessed with the tail-flick test. Withdrawal was precipitated with naloxone. Prazosin potentiated morphine analgesia equally in both genotypes. Clonidine and dexmedetomidine had no analgesic effects in alpha(2A)-adrenoceptor KO mice, but morphine analgesia and tolerance were similar in both genotypes. Alpha(2A)-Adrenoceptor KO mice exhibited 70% fewer naloxone-precipitated jumps than wild-type mice; weight loss was similar in both genotypes. The alpha(2)-adrenoceptor agonists reduced opioid withdrawal signs only in wild-type mice. We conclude that alpha(2A)-adrenoceptors are not directly involved in morphine analgesia and tolerance, and not critical for potentiation of morphine analgesia by prazosin, but that alpha(2A)-adrenoceptors modulate the expression of opioid withdrawal signs in mice.
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Affiliation(s)
- Umit Kazim Ozdogan
- Department of Pharmacology and Clinical Pharmacology, University of Turku, Itäinen Pitkäkatu 4, FI-20520 Turku, Finland
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Florea-Wang D, Haapala E, Mattinen J, Hakala K, Vilpo J, Hovinen J. Reactions of N,N-Bis(2-chloroethyl)-p-aminophenylbutyric Acid (Chlorambucil) with 2‘-Deoxycytidine, 2‘-Deoxy-5-methylcytidine, and Thymidine. Chem Res Toxicol 2004; 17:383-91. [PMID: 15025509 DOI: 10.1021/tx034233q] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
N,N-Bis(2-chloroethyl)-p-aminophenylbutyric acid (chlorambucil, 1; 2.5 mM) was allowed to react with 2'-deoxycytidine, 2'-deoxy-5-methylcytidine, and thymidine (16.1 mM) at physiological pH (cacodylic acid, 50% base), and the reactions were followed by HPLC and HPLC-MS technique. Although the predominant reaction observed was chlorambucil hydrolysis, 1 reacted with various heteroatoms of the nucleosides. The principal site of alkylation with all pyrimidine nucleosides was N3, as judged by 1H NMR and HPLC-MS analyses. Also, several other adducts were detected, which could be tentatively characterized by means of HPLC-MS and MS/MS. As expected, thymidine was the least reactive pyrimidine nucleoside studied, and in addition of the N3 derivative, it reacted only at the carbohydrate moiety. Overall reactivity of cytosine nucleosides with 1 was considerably higher. The N3 adducts of dCyd and 5-Me-dCyd partially deaminated under the reaction conditions employed, but the reaction was not catalyzed by the participation of the omega-hydroxy function of the alkyl substituent but presumably by the nitrogen atom of the chlorambucil moiety. In the case of cytosine nucleosides, the O2 derivatives were the second most abundant species. 5-Me-dCyd reacted more readily at O2 than dCyd. These O2 adducts were labile under acidic, neutral, and basic conditions. No N4 derivatives or cross-links were detected, but dCyd reacted also at C5, although the yield of this derivative was very low. The role of chlorambucil-pyrimidine 2'-deoxyribonucleoside adducts on the cytotoxicity and mutagenity of 1 is also discussed.
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Affiliation(s)
- Diana Florea-Wang
- Department of Chemistry, University of Turku, FIN-20014 Turku, Finland
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Smeds A, Hakala K. Liquid chromatographic-tandem mass spectrometric method for the plant lignan 7-hydroxymatairesinol and its potential metabolites in human plasma. J Chromatogr B Analyt Technol Biomed Life Sci 2003; 793:297-308. [PMID: 12906904 DOI: 10.1016/s1570-0232(03)00330-1] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A HPLC-MS-MS method was developed for the determination of the plant lignan 7-hydroxymatairesinol and its potential metabolites matairesinol, oxomatairesinol, alpha-conidendrin, 7-hydroxyenterolactone, enterodiol, and enterolactone in human plasma. The method included sample cleanup by solid-phase extraction (SPE) and analysis using a PE Sciex API3000 triple quadrupole mass spectrometer with electrospray ionisation. The lignans were quantified using two deuterated internal standards. They showed good chromatographic linearity, analysis repeatability, and SPE recovery in the presence of plasma. In pooled plasma and in plasma samples collected from two individual subjects lignan glucuronides and sulfates were enzymatically hydrolysed to free lignans and then analysed. All the lignans could be detected in the samples.
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Affiliation(s)
- Annika Smeds
- Abo Akademi University, Department of Organic Chemistry, Biskopsgatan 8, FIN-20500, Turku, Finland.
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Florea-Wang D, Haapala E, Mattinen J, Hakala K, Vilpo J, Hovinen J. Reactions of N,N-bis(2-chloroethyl)-p-aminophenylbutyric acid (chlorambucil) with 2'-deoxyadenosine. Chem Res Toxicol 2003; 16:403-8. [PMID: 12641441 DOI: 10.1021/tx0256735] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
N,N-bis(2-chloroethyl)-p-aminophenylbutyric acid (chlorambucil, 1; 0.6 mM) was allowed to react with 2'-deoxyadenosine (16.1 mM) at physiological pH (cacodylic acid, 50% base), and the reactions were followed by HPLC-MS and HPLC-MS/MS techniques. Although the predominant reaction observed was chlorambucil hydrolysis, ca. 7% of 1 reacted with various heteroatoms of the nucleoside. The principal site of alkylation was N1. Several other adducts were also detected. The N1, N6, N3, and N7 derivatives were characterized by means of MS/MS, UV, and (1)H NMR. The N6 adduct is derived directly from alkylation of N6 of 2'-dAdo. Dimroth rearrangement of the N1 adduct to the N6 adduct was very slow under the reaction conditions employed. Minor adducts such as a carbohydrate derivative were tentatively characterized by MS/MS. No cross-links were detected. The role of chlorambucil-2'-deoxyadenosine adducts in the cytotoxicity and mutagenicity of 1 is also discussed.
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Affiliation(s)
- Diana Florea-Wang
- Department of Chemistry, University of Turku, FIN-20014 Turku, Finland
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Saarinen NM, Smeds A, Mäkelä SI, Ammälä J, Hakala K, Pihlava JM, Ryhänen EL, Sjöholm R, Santti R. Structural determinants of plant lignans for the formation of enterolactone in vivo. J Chromatogr B Analyt Technol Biomed Life Sci 2002; 777:311-9. [PMID: 12270222 DOI: 10.1016/s1570-0232(02)00339-2] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
The quantity of mammalian lignans enterolactone (ENL) and enterodiol (END) and of plant lignans secoisolariciresinol (SECO) and 7-hydroxymatairesinol (HMR) excreted in a 24-h rat urine sample was measured after a single p.o. dose of an equivalent quantity of secoisolariciresinol diglycoside (SDG), secoisolariciresinol (SECO), matairesinol (MR), 7-hydroxymatairesinol (HMR) and ENL. Plant lignans (SECO and HMR) were partially absorbed as such. The aglycone form of SECO was more efficiently converted into mammalian lignans END and ENL than the glycosylated form, SDG. Of plant lignans, MR produced the highest quantities of ENL: the quantity was over twofold compared with HMR or SDG. The majority of the animals, which had been given SECO, excreted higher quantities of END than ENL into urine, but ENL was the main lignan metabolite after SDG. The highest quantities of ENL in urine were measured after the administration of ENL as such. The (-)SECO isolated from Araucaria angustifolia was converted into (-)ENL only. The administration of (-)SDG, which was shown to produce (+)SECO, resulted in excretion of (+)ENL only and (-)HMR was converted into (-)ENL only. This confirmed that the absolute configurations at C8 and C8' are not changed during the microbial metabolism. Whether the biological effects are enantiomer-specific, remains to be resolved.
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Affiliation(s)
- Niina M Saarinen
- Department of Anatomy, Institute of Biomedicine, University of Turku, FIN-20520, Turku, Finland
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15
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Tang Z, Li B, Bharadwaj R, Zhu H, Ozkan E, Hakala K, Deisenhofer J, Yu H. APC2 Cullin protein and APC11 RING protein comprise the minimal ubiquitin ligase module of the anaphase-promoting complex. Mol Biol Cell 2001; 12:3839-51. [PMID: 11739784 PMCID: PMC60759 DOI: 10.1091/mbc.12.12.3839] [Citation(s) in RCA: 144] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
In mitosis, the anaphase-promoting complex (APC) regulates the onset of sister-chromatid separation and exit from mitosis by mediating the ubiquitination and degradation of the securin protein and mitotic cyclins. With the use of a baculoviral expression system, we have reconstituted the ubiquitin ligase activity of human APC. In combination with Ubc4 or UbcH10, a heterodimeric complex of APC2 and APC11 is sufficient to catalyze the ubiquitination of human securin and cyclin B1. However, the minimal APC2/11 ubiquitin ligase module does not possess substrate specificity, because it also ubiquitinates the destruction box deletion mutants of securin and cyclin B1. Both APC11 and UbcH10 bind to the C-terminal cullin homology domain of APC2, whereas Ubc4 interacts with APC11 directly. Zn(2+)-binding and mutagenesis experiments indicate that APC11 binds Zn(2+) at a 1:3 M ratio. Unlike the two Zn(2+) ions of the canonical RING-finger motif, the third Zn(2+) ion of APC11 is not essential for its ligase activity. Surprisingly, with Ubc4 as the E2 enzyme, Zn(2+) ions alone are sufficient to catalyze the ubiquitination of cyclin B1. Therefore, the Zn(2+) ions of the RING finger family of ubiquitin ligases may be directly involved in catalysis.
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Affiliation(s)
- Z Tang
- Departments of Pharmacology, The University of Texas Southwestern Medical Center at Dallas, Dallas, TX 75390-9041, USA
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16
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Haapala E, Hakala K, Jokipelto E, Vilpo J, Hovinen J. Reactions of N,N-bis(2-chloroethyl)-p-aminophenylbutyric acid (chlorambucil) with 2'-deoxyguanosine. Chem Res Toxicol 2001; 14:988-95. [PMID: 11511172 DOI: 10.1021/tx000249u] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
N,N-Bis(2-chloroethyl)-p-aminophenylbutyric acid (chlorambucil, 1) was allowed to react in the presence of 2'-deoxyguanosine (16 mM) at physiological pH (cacodylic acid, 50% base), and the reactions were followed by HPLC/MS/MS techniques. Although the predominant reaction observed was chlorambucil hydrolysis, ca. 24% of 1 reacted with different heteroatoms of the nucleoside. As expected, the principal site of 2'-deoxyguanosine alkylation was N7. Alkylation of N7 caused spontaneous depurination, and N-(7-guaninylethyl)-N-hydroxyethyl-p-aminophenylbutyric acid (5) and the corresponding N7,N7-bis-adduct (6) were the major stable dGuo derivatives. Also several other adducts were detected and tentatively identified by means of MS/MS and UV. From them, the O(6-), N1-, N(2-), and O5'-derivatives can be biologically significant. Our results shed new light on DNA modifications caused by chlorambucil, which is an important chemotherapeutic drug and a known carcinogen.
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Affiliation(s)
- E Haapala
- Department of Chemistry, University of Jyväskylä, FIN-40351 Jyväskylä, Finland
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17
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Hakala K, Vatanparast R, Vuorimaa E, Lemmetyinen H. Monitoring water uptake of polyurethanes byin situ fluorescence technique. J Appl Polym Sci 2001. [DOI: 10.1002/app.1998] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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18
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Hakala K, Stenius-Aarniala B, Sovijärvi A. Effects of weight loss on peak flow variability, airways obstruction, and lung volumes in obese patients with asthma. Chest 2000; 118:1315-21. [PMID: 11083680 DOI: 10.1378/chest.118.5.1315] [Citation(s) in RCA: 197] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
STUDY OBJECTIVES To clarify the pathophysiologic features of the relation between asthma and obesity, we measured the effects of weight reduction on peak expiratory flow (PEF) variability and airways obstruction, compared to simultaneous changes in lung volumes and ventilatory mechanics in obese patients with stable asthma. METHODS Fourteen obese asthma patients (11 women and 3 men; aged 25 to 62 years) were studied before and after a very-low-calorie-diet period of 8 weeks. PEF variability was determined as diurnal and day-to-day variations. FEV(1) and maximal expiratory flow values were measured with a flow-volume spirometer. Lung volumes, airways resistance (Raw), and specific airways conductance were measured using a constant-volume body plethysmograph. Minute ventilation was monitored in patients in supine and standing positions. RESULTS As patients decreased their body mass index (SD) from 37.2 (3.7) to 32.1(4.2) kg/m(2) (p < 0. 001), diurnal PEF variation declined from 5.5% (2.4) to 4.5% (1.5) (p = 0.01), and day-to-day variation declined from 5.3% (2.6) to 3. 1% (1.3) (p < 0.005). The mean morning PEF, FEV(1), and FVC increased after weight loss (p = 0.001, p < 0.005, and p < 0.05, respectively). Flow rate at the middle part of FVC (FEF(25-75)) increased even when related to lung volumes (FEF(25-75)/FVC; p < 0. 05). Functional residual capacity and expiratory reserve volume were significantly higher after weight loss (p < 0.05 and p < 0.005, respectively). A significant reduction in Raw was found (p < 0.01). Resting minute ventilation decreased after weight loss (p = 0.01). CONCLUSION Weight loss reduces airways obstruction as well as PEF variability in obese patients with asthma. The results suggest that obese patients benefit from weight loss by improved pulmonary mechanics and a better control of airways obstruction.
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Affiliation(s)
- K Hakala
- Department of Medicine, Helsinki University Hospital, Helsinki, Finland
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19
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Abstract
The 26 S proteasome is a large protease complex that catalyzes the degradation of both native and misfolded proteins. These proteins are known to interact with PA700, the regulatory subcomplex of the 26 S proteasome, via a covalently attached polyubiquitin chain. Here we provide evidence for an additional ubiquitin-independent mode of substrate recognition by PA700. PA700 prevents the aggregation of three incompletely folded, nonubiquitinated substrates: the DeltaF-508 mutant form of cystic fibrosis transmembrane regulator, nucleotide binding domain 1, insulin B chain, and citrate synthase. This function does not require ATP hydrolysis. The stoichiometry required for this function, the effect of PA700 on the lag phase of aggregation, and the temporal specificity of PA700 in this process all indicate that PA700 interacts with a subpopulation of non-native conformations that is either particularly aggregation-prone or nucleates misassociation reactions. The inhibition of off-pathway self-association reactions is also reflected in the ability of PA700 to promote refolding of citrate synthase. These results provide evidence that, in addition to binding polyubiquitin chains, PA700 contains a site(s) that recognizes and interacts with misfolded or partially denatured polypeptides. This feature supplies an additional level of substrate specificity to the 26 S proteasome and a means by which substrates are maintained in a soluble state until refolding or degradation is complete.
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Affiliation(s)
- E Strickland
- Program in Molecular Biophysics, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75235, USA
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20
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Hakala K, Maasilta P, Sovijärvi AR. Upright body position and weight loss improve respiratory mechanics and daytime oxygenation in obese patients with obstructive sleep apnoea. Clin Physiol 2000; 20:50-5. [PMID: 10651792 DOI: 10.1046/j.1365-2281.2000.00223.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
To determine whether upright body position and weight loss would improve daytime gas exchange in moderately obese patients with obstructive sleep apnoea (OSAS), 13 patients with mild or moderate OSAS were studied before and after weight loss. Pulmonary function tests, arterial blood gases and respiratory gas analysis were measured prior to and after a very low calorie diet (VLCD) period of six weeks. Arterial blood gases were measured in supine and standing positions and closing volume in supine and sitting positions before and after weight loss. In the upright position, there was a significant increase in PaO2 (P<0.005) accompanied by a significant decrease in alveolar-arterial PO2 difference (P<0.005) and closing volume (P<0.05). The median weight loss was 11 kg (range 5-18). The number of desaturation episodes (four percentage units or more per hour during sleep) (ODI4) decreased (P<0.01) after weight loss. The change in PaO2 with weight loss correlated with the decrease in ODI4 (r=0.73, P<0.01). The increase in expiratory reserve volume (ERV) was closely related to the amount of weight lost (r=0.895, P<0.01). The results indicate that weight loss and upright body position improved daytime respiratory mechanics and gas exchange in obese patients with OSAS. The findings suggest that obesity plays an important role in the pathogenesis of daytime gas exchange disturbances in obese OSAS patients. The adoption of a more upright sleep posture might improve nocturnal oxygenation in obese patients with OSAS.
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Affiliation(s)
- K Hakala
- Department of Medicine, Division of Pulmonary Medicine, Helsinki University Hospital, Helsinki, Finland
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21
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Hakala K, Auriola S, Koivisto A, Lönnberg H. Mass spectrometric (HPLC/ESI--MS/MS) quantification of pyrimido[1,3-a]purin-10(3H)-one, a guanine adduct formed by reaction of malondialdehyde with DNA. J Pharm Biomed Anal 1999; 21:1053-61. [PMID: 10703974 DOI: 10.1016/s0731-7085(99)00228-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
A high performance liquid chromatography/electrospray ionization tandem mass spectrometric (HPLC/ESI MS/MS) method has been developed for quantification of pyrimido[1,2-a]purin-10(3H)-one adducts from DNA. The method is based on acid-catalyzed cleavage of the adducts from DNA and the use of [2,3a,10-13C3]pyrimido[1,2-a]purin-10(3H)-one as an internal standard in the analysis. For this purpose the latter compound was prepared. Rate constants for the acid-catalyzed cleavage of pyrimido[1,2-a]purin-10(3H)-one from the corresponding 2'-deoxyribonucleoside were determined, and its hydrolytic stability and possible formation by a cross reaction between guanine and [2,3a,10]pyrimido[1,2-a]purin-10(3H)-one were studied.
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Affiliation(s)
- K Hakala
- Department of Chemistry, University of Turku, Finland
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22
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Mikkola S, Andersson S, Hakala K, Antoni G, Björkman M, Forngren BH, Forngren T, Hartvig P, Markides K, Yngve U, Ögren M. The Hydrolytic Stability of Hydroxypropano Adducts of 2'-Deoxyguanosine Formed by Reaction with Acrolein and Crotonaldehyde. ACTA ACUST UNITED AC 1999. [DOI: 10.3891/acta.chem.scand.53-0642] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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23
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Pettersson-Fernholm T, Vilpo J, Kosonen M, Hakala K, Hovinen J. Reactions of 4-bis(2-chloroethyl)aminophenylacetic acid (phenylacetic acid mustard) in physiological solutions. ACTA ACUST UNITED AC 1999. [DOI: 10.1039/a903013a] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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24
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Lund H, Skov K, Hakala K, Antoni G, Björkman M, Forngren BH, Forngren T, Hartvig P, Markides K, Yngve U, Ögren M. Reaction of a Pyridinium Salt with N,N-Dimethylhydrazine. ACTA ACUST UNITED AC 1999. [DOI: 10.3891/acta.chem.scand.53-0639] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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25
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Turunen UM, Färkkilä MA, Hakala K, Seppälä K, Sivonen A, Ogren M, Vuoristo M, Valtonen VV, Miettinen TA. Long-term treatment of ulcerative colitis with ciprofloxacin: a prospective, double-blind, placebo-controlled study. Gastroenterology 1998; 115:1072-8. [PMID: 9797360 DOI: 10.1016/s0016-5085(98)70076-9] [Citation(s) in RCA: 167] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND & AIMS Although bacterial bowel flora may be one of the contributing factors in the pathogenesis of chronic mucosal inflammation, antibiotic treatment has no established role in ulcerative colitis. The aim of the study was to evaluate the role of ciprofloxacin in the induction and maintenance of remission in ulcerative colitis in patients responding poorly to conventional therapy with steroids and mesalamine. METHODS Ciprofloxacin (n = 38; 500-750 mg twice a day) or placebo (n = 45) was administered for 6 months in a double-blind, randomized study with a high but decreasing dose of prednisone and maintenance treatment with mesalamine including follow-up for the next 6 months. Clinical assessment and colonoscopic evaluation were performed at 0, 3, 6, and 12 months. Treatment failure, the primary end point, was defined as both symptomatic and endoscopic failure to respond. RESULTS During the first 6 months, the treatment-failure rate was 21% in the ciprofloxacin-treated group and 44% in the placebo group (P = 0.02). Endoscopic and histological findings were used as secondary end points and showed better results in the ciprofloxacin group at 3 months but not at 6 months. CONCLUSIONS Addition of a 6-month ciprofloxacin treatment for ulcerative colitis improved the results of conventional therapy with mesalamine and prednisone.
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Kosonen M, Hakala K, Lönnberg H. Hydrolysis and intramolecular transesterification of ribonucleoside 3′-phosphotriesters: the effect of alkyl groups on the general and specific acid–base-catalyzed reactions of 5′-O-pivaloyluridin-3′-yl dialkyl phosphates. ACTA ACUST UNITED AC 1998. [DOI: 10.1039/a707095k] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Abstract
BACKGROUND No data exist on cholesterol absorption in patients with an ileoanal anastomosis (IAA). AIMS To study cholesterol absorption and its effects on cholesterol and bile acid metabolism in patients with an IAA. PATIENTS AND METHODS Cholesterol absorption, and serum, biliary, and faecal lipids were studied in 24 patients with an IAA and 20 controls. RESULTS Fractional cholesterol absorption was significantly lower in the patients (36% versus 47% in controls). Surprisingly, the calculated intestinal influx of endogenous cholesterol was reduced so that the absolute absorption of cholesterol was decreased; elimination of cholesterol as faecal neutral steroids remained normal. Thus, the slightly increased cholesterol synthesis was mainly due to increased faecal bile acid excretion, which, in turn, was associated with reduced absorption and biliary secretion of bile acids. Serum total and low density lipoprotein (LDL) cholesterol and LDL triglycerides were lower in the patients. Molar percentage and saturation index of biliary cholesterol were slightly higher in patients with an IAA. Proportions of secondary bile acids in bile and faeces were diminished, and faecal unidentified bile acids were higher in patients. CONCLUSIONS Cholesterol absorption is significantly impaired in patients with an IAA, and is closely related to changes in serum and biliary lipids observed in these patients.
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Affiliation(s)
- K Hakala
- Department of Medicine, University of Helsinki, Finland
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Abstract
BACKGROUND Previous studies suggest only minor changes in bile acid metabolism after panproctocolectomy with ileal pouch construction. AIMS/METHODS To investigate these changes further, we studied cholesterol absorption and serum, biliary and fecal non-cholesterol sterols and lipids in 12 ileal pouch patients and 10 controls. RESULTS In patients, cholesterol absorption was markedly reduced and was associated with low serum total and LDL cholesterol and LDL triglyceride levels, but surprisingly, cholesterol synthesis, as indicated by sterol-balance data or serum cholesterol precursor levels, was within low normal limits. The high proportions of serum plant sterol to cholesterol, particularly that of campesterol, were not related to cholesterol absorption, but were attributable to a markedly reduced biliary cholesterol secretion. Interestingly, in these patients the fractional absorption of campesterol was normal, whereas that of sitosterol, like cholesterol, was reduced and was positively related to the intestinal influx of cholesterol. The patients' serum cholestanol proportion was normal, but the proportion of the cholestanol formed during intestinal passage was significantly reduced (17.9% vs 65.2% in controls). CONCLUSIONS Thus ileal pouch patients are characterized by sterol malabsorption, lowered serum total and LDL-cholesterol levels, but unexpectedly without any increase in cholesterol synthesis. The lack of high serum cholestanol, shown earlier frequently in unoperated patients with ulcerative colitis, may indicate reversible cholestasis, a finding deserving further exploration.
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Affiliation(s)
- K Hakala
- Department of Medicine, University of Helsinki, Finland
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Abstract
The aim of this study was to determine the effect of weight loss induced by 6 weeks very-low-calorie-diet (VLCD) and behavioural intervention on pulmonary gas exchange during exercise in non-smoking morbid obese (BMI>40 kg/m2) otherwise healthy patients. Seven obese patients underwent a maximal bicycle ergometer test with continuous analysis of expired air and arterial blood sampling before and after a mean weight loss of 18% (25.7 kg, range: 10-50 kg). Body mass index (BMI) decreased with weight loss from 46.6 (6.3) kg/m2 to 38.0 (4.7) kg/m2 (P<0.01). Oxygen consumption (VO2) at low and submaximal exercise levels decreased after weight reduction, but the change was not statistically significant. The peak oxygen consumption related to body weight (VO2/kg) increased 22% from the initial 16.2 (3.6) ml/min/kg to 19.8 (3.1) ml/min/kg (P<0.05). Decrease in VCO2 was significant at submaximal exercise level. Ventilatory equivalent for CO2 increased significantly after weight reduction (P<0.05). Standing up and light exercise resulted in a significant increase in the mean arterial oxygen tension (PaO2) (P<0.05) and a significant decrease in the mean alveolar-arterial difference P(A-a)O2 (P<0.05) when compared to supine values. The mean increase in PaO2 with weight loss was not significant. The peak P(A-a)O2 decreased significantly after weight reduction. In conclusion, weight reduction induced by VLCD and behavioural intervention without exercise therapy can improve gas exchange during exercise in morbid obesity. Increased wasted ventilation, and a tendency to alveolar hyperventilation, after weight loss may reflect a delay in the adaptation of regulation of breathing to rapid weight loss.
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Affiliation(s)
- K Hakala
- Department of Medicine, Division of Pulmonary Medicine and Clinical Physiology, Helsinki University Hospital, Finland
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Abstract
The role of cholestasis and ileal dysfunction on sterol metabolism was studied in 79 patients with inflammatory bowel diseases (IBDs) and in 23 irritable bowel syndrome (IBS) controls by determining serum sterol/cholesterol proportions. The sterols included cholesterol precursors (delta 8-cholestenol, desmosterol and lathosterol), markers of cholesterol synthesis, cholestanol and plant sterols (campesterol and sitosterol), markers of cholesterol absorption and biliary secretion. The IBD patients were subgrouped into distal ulcerative colitis (dUC, n = 21), pancolitis (pUC, n = 29), ileal Crohn's disease (iCD, n = 20) and colonic Crohn's disease (cCD, n = 9). The cholestanol proportions were increased in the 3 colonic IBD groups, up to two times in cCD patients and seven times in a case with clinically overt primary sclerosing cholangitis, but were within the control IBS levels in the patients with iCD. The sitosterol, but not campesterol, proportion was significantly increased only in the pUC group. In the iCD group only the serum precursor sterol proportions, especially those for delta 8-cholestenol and lathosterol, were elevated probably due to ileal dysfunction induced bile acid malabsorption and compensatorily increased cholesterol synthesis. In conclusion, the findings suggest that the increased cholestanol proportion in colonic IBD is determined mainly by impaired biliary elimination of this sterol, while in ileal affision the dominating change in sterol balance is activated cholesterol synthesis. Thus increased serum cholestanol is a novel finding in colonic IBD, apparently indicating the presence of subclinical cholestasis in a marked number (20-50%) of IBD patients.
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Affiliation(s)
- K Hakala
- Division of Internal Medicine, University of Helsinki, Finland
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Hakala K, Mustajoki P, Aittomäki J, Sovijärvi AR. Effect of weight loss and body position on pulmonary function and gas exchange abnormalities in morbid obesity. Int J Obes Relat Metab Disord 1995; 19:343-6. [PMID: 7647827] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
OBJECTIVE To determine, whether behavioral management of obesity including very-low-calorie-diet would produce weight loss enough to improve pulmonary mechanics and gas exchange in morbid obesity. DESIGN Pulmonary function and arterial oxygenation were studied before and after weight loss in 11 patients attending a group therapy with the program of VLCD for 6 weeks and 16 weeks' behavioral intervention. MEASUREMENTS Spirometry, diffusing capacity, body plethysmograph, closing volume and arterial blood gas analyses. RESULTS The mean initial BMI was 45.4 kg/m2 (range 39.8-58.7 kg/m2) and decreased to 39.4 kg/m2 (range 31-49.8 kg/m2) (P < 0.01). Expiratory reserve volume (ERV) and functional residual capacity (FRC) improved significantly with weight loss. Closing capacity (CC) exceeded FRC in 10 cases of 11 at the initial stage, but after weight loss only in three patients. The mean arterial oxygen tension with the patients in supine position did not change after weight loss, but standing up improved PaO2 significantly before and after weight loss. CONCLUSION The dietary treatment of morbid obesity was sufficient to induce improvement in lung volumes, but not enough to improve arterial oxygenation, although ventilatory mechanics was improved significantly and the tendency to early small airway closure was decreased. Hypoxemia was significantly relieved by standing up both before and after weight loss.
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Affiliation(s)
- K Hakala
- Department of Pulmonary Diseases, Helsinki University Central Hospital, Finland
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Seppälä K, Färkkilä M, Nuutinen H, Hakala K, Väänänen H, Rautelin H, Kosunen TU. Triple therapy of Helicobacter pylori infection in peptic ulcer. A 12-month follow-up study of 93 patients. Scand J Gastroenterol 1992; 27:973-6. [PMID: 1455197 DOI: 10.3109/00365529209000173] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
This study was undertaken to evaluate the success of triple therapy in peptic ulcer patients and ulcer relapses. One hundred and one consecutive Helicobacter pylori-positive peptic ulcer patients were assigned to an open trial with 2 weeks of treatment with colloidal bismuth subcitrate, amoxicillin, and metronidazole. At the 6-week follow-up only 1 duodenal ulcer was unhealed of 57 active ulcers, and H. pylori was found to be eradicated in 84% of the 100 subjects. The sensitivity to metronidazole was determined from 71 pretreatment strains of H. pylori. Eradication of H. pylori succeeded in 89% of the patients with metronidazole-susceptible strains and in 61% of patients with metronidazole-resistant strains (p < 0.03). All 16 patients in whom the treatment failed to eradicate the organism had metronidazole-resistant strains after treatment. The ulcer relapse rate was low. At the 12-month follow-up of 93 patients only 1 of the 84 H. pylori-negative patients (including 4 patients after new successful therapy) had relapsing ulcers (2 asymptomatic episodes), and 1 had H. pylori reinfection, whereas 3 of the 9 bacteria-positive patients relapsed (p = 0.002); at the 2-year control 2 more patients had ulcer relapses. The eradication of H. pylori infection clearly prevents relapses of peptide ulcer, but the success of triple therapy depends on the frequency of pretreatment metronidazole-resistant H. pylori strains.
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Affiliation(s)
- K Seppälä
- Second Dept. of Medicine, Helsinki University Central Hospital, Finland
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Hawkins J, Hakala K, Heller MB, Kaplan RM, Schneider S, Stewart RD. Metered-dose aerosolized bronchodilators in prehospital care: a feasibility study. J Emerg Med 1986; 4:273-7. [PMID: 3540093 DOI: 10.1016/0736-4679(86)90001-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The prehospital use of aerosolized bronchodilators was studied in 50 adult patients with bronchospasm. The specific beta 2-agonist, albuterol, was discharged from a metered-dose inhaler (MDI) into the Inhal-aid reservoir-delivery device. No serious adverse effects were encountered, although a substantial proportion of the patients (36%) had difficulty utilizing the device. Ability to use the system properly correlated with improvement in symptoms; inability to use the device was most clearly related to severity of clinical presentation. It is concluded that the use of aerosolized bronchodilators is feasible in prehospital care and most useful in patients with mild or moderately severe symptoms.
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