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Biomedical subjects

J Tapanainen

Publications and source records attributed to J Tapanainen.

At least 19 recordsLinked to original sources
PubMed2002

Intrauterine 10 microg and 20 microg levonorgestrel systems in postmenopausal women receiving oral oestrogen replacement therapy: clinical, endometrial and metabolic response.

OBJECTIVE: The clinical and endometrial efficacy and lipid response of two different doses of intrauterine levonorgestrel were assessed in comparison with sequential oral medroxyprogesterone acetate in postmenopausal women receiving continuous oral E2-valerate. DESIGN: One-year prospective multicentre randomised control trial. SETTING: Four outpatient clinics in Oulu, Helsinki and Jyväskylä, Finland. POPULATION: A total of 163 healthy volunteer postmenopausal women with climacteric complaints or already using hormone replacement therapy (HRT). INTERVENTIONS: Subjects were randomly allocated to receive a new intrauterine system releasing 10 microg of levonorgestrel daily or an established intrauterine system (Mirena) releasing 20 microg of levonorgestrel daily or sequential oral medroxyprogesterone acetate (5mg/day, 14/30 days). All three regimens were combined with an oral daily dose of 2mg of E2-valerate. MAIN OUTCOME MEASURES: Bleeding patterns were assessed by diaries kept by the subjects. Endometrial effects were evaluated by histologic biopsies taken at the baseline and after six and 12 months of therapy. Serum concentrations of total, HDL and LDL cholesterol, triglycerides and lipoprotein(a) were determined at the baseline and after six and 12 months of therapy. RESULTS: Insertion of the smaller 10 microg levonorgestrel system was easy in 70% and difficult in 4% and that of Mirena was easy in 46% and difficult in 21% of the subjects. After six months of therapy, 43 (95.6%) of the 47 subjects receiving 10 microg levonorgestrel and 54 (98.2%) of the 55 subjects receiving 20 microg levonorgestrel had no bleeding, while the sequential medroxyprogesterone acetate regimen produced typical cyclic withdrawal bleedings. Endometrial hyperplasia was not observed in any of the treatment groups during the 12-month study. After 12 months of therapy, strong endometrial suppression was found in 46/47 and 55/55 of the subjects receiving 10 microg and 20 microg of levonorgestrel, respectively, while the endometrium was proliferative in 18/47 of the subjects in the medroxyprogesterone acetate group. Serum total cholesterol decreased in all treatment groups. HDL cholesterol increased in women receiving medroxyprogesterone acetate or the smaller intrauterine dose of levonorgestrel. CONCLUSIONS: Both intrauterine doses of levonorgestrel provided good endometrial protection in postmenopausal women on oestrogen replacement therapy. The advantage of the 10 microg system with a smaller size is the easier insertion of the system and a minimal attenuation of the favourable effects of oral oestrogen on the serum lipid profile.

Administration, Intravaginal↗
PubMed2001

The identification of secreted carbonic anhydrase VI as a constitutive glycoprotein of human and rat milk.

In addition to essential nutrients, human milk contains several classes of bioactive factors such as enzymes, hormones, and growth factors, many of which are implicated in infantile growth and development. Secretory carbonic anhydrase isoenzyme VI (CA VI) has been identified earlier as an essential component of mammalian saliva, and we demonstrate here by using biochemical and immunohistochemical techniques that it is also an elementary component of milk. The 42-kDa glycopolypeptide purified from human milk in CA inhibitor affinity chromatography shared 100% homology with salivary CA VI in the protein sequence analysis (40% coverage), and its digestion with PNGase F resulted in a polypeptide backbone similar in size to salivary CA VI. Quantification of CA VI in milk by using a time-resolved immunofluorometric assay revealed an approximately eight-times-higher concentration in human colostrum than in mature milk, the latter corresponding to the levels previously detected in human saliva. The high concentration in the colostrum, in particular its functional and structural stability in an acidic milieu, and its growth-supporting role in the taste buds suggest that milk CA VI is an essential factor in normal growth and development of the infant alimentary tract.

Animals↗
PubMed2001

One versus two embryo transfer after IVF and ICSI: a randomized study.

BACKGROUND: The main reason for adverse treatment outcome in assisted reproduction is the high rate of multiple pregnancies. The only strategy to avoid dizygotic twins is to transfer one embryo at a time. METHODS: A total of 144 women, who had had at least four good quality embryos available after IVF/intracytoplasmic sperm injection (ICSI) and who had no more than one previous failed treatment cycle, were randomized to have either one or two embryos transferred. The treatment outcomes including those after frozen embryo transfer were compared between these groups. RESULTS: The clinical pregnancy rate per transfer was 32.4% in the one embryo transfer group and 47.1% in the two embryo transfer group, the difference being not significant. Eleven twin deliveries (n = 39) occurred in the two embryo transfer group and there was one pair of monozygotic twins in the one embryo transfer group. The cumulative pregnancy rate per patient after transfer of fresh and frozen embryos was 47.3% in the one embryo transfer group and 58.6% in the two embryo transfer group. CONCLUSIONS: Our results indicate that among women who have good quality embryos in their first IVF/ICSI, good treatment results can be achieved. They support the idea of changing embryo transfer policy towards one embryo transfer without any remarkable decrease in the success rate, while dizygotic twins can be avoided.

Adult↗
PubMed2001

[Andropause].

Explore the source record for details and available documents.

Aging↗
PubMed2000

Identification of carbonic anhydrase XII as the membrane isozyme expressed in the normal human endometrial epithelium.

Although previous studies demonstrated carbonic anhydrase (CA) activity in the human endometrium, the CA isozyme(s) responsible for this activity has not been established. In this report, we provide the first evidence that the CA isozyme XII, a recently identified transmembrane isozyme that is expressed in normal kidney and greatly overexpressed in some renal cancers, is present in endometrium. We show by immunohistochemistry that CA XII is expressed in the basolateral plasma membrane of epithelial cells of normal human endometrium. Expression of CA XII in uterus was confirmed by Northern blotting. Detergent-solubilized CA XII was isolated from human endometrium by inhibitor affinity chromatography and characterized by isoelectric focusing and Western blot as a polypeptide with a pI of 6.3. The high expression of CA XII in the endometrial epithelium suggests that it may be functionally linked to the pH-dependent events in spermatozoa that precede fertilization. Its basolateral location and extracellular active site could also allow it to influence the morphological changes in endometrium that occur during the menstrual cycle.

Animals↗
PubMed1999

The prevalence of polycystic ovaries in healthy women.

BACKGROUND: To study the prevalence of polycystic ovaries (PCO) in women of reproductive age. METHODS: A total of 189 healthy volunteers aged 20-45 years were examined. The subjects were divided into two groups according to age: < or =35 and > or =36 years. Transvaginal ultrasonography was performed and blood samples were collected on cycle day 1-6. RESULTS: The prevalence of PCO in the entire study population was 14.2% (27/189). In the age group of < or =35 years the prevalence was 21.6% (19/88) and in the age group of > or =36 years 7.8% (8/101). Compared to women with normal ovaries, those with PCO had significantly higher serum testosterone (T) concentrations. Women with PCO tended to have lower serum FSH concentrations and higher LH/FSH ratios than controls. Women with PCO had significantly more irregular cycles (44% vs. 19%, p=0.001) and problems in conceiving (25.9% vs. 9.2%, p=0.01) than women with normal ovaries. CONCLUSIONS: The findings demonstrate that the prevalence of PCO in healthy women varies with age, being more common among women aged < or =35 years than in those aged > or =36 years. Although the hormonal parameters and clinical findings among women with PCO mimicked those of PCOS, it remains unclear if these women will later develop full-blown syndrome.

Adult↗
PubMed1998

Placental mitochondrial DNA and respiratory chain enzymes in the etiology of preeclampsia.

OBJECTIVE: To evaluate the occurrence of the most common mutations and deletions in mitochondrial DNA and deficiencies in the enzyme complexes of the mitochondrial respiratory chain in placentas from preeclamptic women. METHODS: Mitochondria were isolated from the placentas of 17 preeclamptic or 25 control women, and the activities of mitochondrial respiratory chain complexes were measured. Deletions and three common point mutations of mitochondrial DNA were searched for by the Southern blot and polymerase chain reaction (PCR) methods from the same placentas. RESULTS: Mean (+/- standard deviation) mitochondrial respiratory chain enzyme complex activities in placentas on protein basis (nmol/min/mg of protein) were similar in preeclamptics and controls (nicotinamide adenine dinucleotide, reduced form-ubiquinone oxidoreductase 25.84 +/- 9.29 versus 31.02 +/- 7.52; nicotinamide adenine dinucleotide, reduced form-cytochrome-c oxidoreductase 77.88 +/- 42.24 versus 104.06 +/- 56.73; succinate-cytochrome-c oxidoreductase 57.90 +/- 13.83 versus 64.44 +/- 20.16; cytochrome-c oxidase 106.43 +/- 35.46 versus 128.37 +/- 48.64, respectively) and they were similar also when referenced to the mitochondrial marker enzyme citrate synthase. The sample sizes in both patient and control groups were found to be large enough by post hoc test. Large-scale deletions or the common 5-kb and 7.4-kb deletions were not detected, even at the sensitivity level of PCR. The three most common point mutations were not found in either control or preeclamptic placental samples. CONCLUSION: Common mitochondrial DNA mutations seem to play no major role in the universal etiology of preeclampsia, as assessed by analysis of the mitochondrial genome and respiratory chain enzyme activities in vitro. This does not exclude possible alterations in the energy state of the preeclamptic placenta.

Adult↗
PubMed1998

Human 17beta-hydroxysteroid dehydrogenase type 2 messenger ribonucleic acid expression and localization in term placenta and in endometrium during the menstrual cycle.

According to the current hypothesis, 17beta-hydroxysteroid dehydrogenases (17HSDs) regulate the extent of estrogen influence in the endometrium by converting estradiol (E2) locally into a biologically less active sex steroid, estrone (E1), and vice versa. Recently, we have shown that both 17HSD type 1 and type 2 are expressed in the human endometrium, and in the present work, using in situ hybridization, we show that 17HSD type 2 is localized in the glandular epithelial cells as previously shown for the type 1 enzyme, but in contrast to type 1, the expression of type 2 is highest at the end of the cycle. Hence, we hypothesize that the differential expression of the two 17HSD enzymes, with opposite activities in same cell types, could modulate intracellular E2 concentrations during the end of the luteal phase of the menstrual cycle. We further analyzed the expression of 17HSD type 1 and type 2 mRNAs in term human placenta. Expression of 17HSD type 1 mRNA was detected in the syncytiotrophoblasts, and signals for type 2 mRNA were found inside the villi, corresponding to cytotrophoblasts. The expression of 17HSD type 2 in the placenta may serve to maintain the presence of inactive sex steroids and attenuate the formation of biologically potent androgens and estrogens.

17-Hydroxysteroid Dehydrogenases↗
PubMed1995

Mutation in the follicle-stimulating hormone receptor gene causes hereditary hypergonadotropic ovarian failure.

Hypergonadotropic ovarian dysgenesis (ODG) with normal karyotype is a heterogeneous condition that in some cases displays Mendelian recessive inheritance. By systematically searching for linkage in multiplex affected families, we mapped a locus for ODG to chromosome 2p. As the previously cloned follicle-stimulating hormone receptor (FSHR) gene had been assigned to 2p, we searched it for mutations. A C566T transition in exon 7 of FSHR predicting an Ala to Val substitution at residue 189 in the extracellular ligand-binding domain segregated perfectly with the disease phenotype. Expression of the gene in transfected cells demonstrated a dramatic reduction of binding capacity and signal transduction, but apparently normal ligand-binding affinity of the mutated receptor. We conclude that the mutation causes ODG in these families.

Base Sequence↗
PubMed1995

Apoptosis in testis germ cells: developmental changes in gonadotropin dependence and localization to selective tubule stages.

Recent studies have demonstrated apoptotic DNA fragmentation in the testis of immature rats deprived of gonadotropins. However, the exact cell type undergoing apoptosis during testis development and the age differences of gonadotropin dependence of testis cell apoptosis are unclear. The present study used gel fractionation and in situ methods to quantitate developmental changes of testis cell DNA fragmentation and to localize the specific cell type affected in developing rats with and without treatment with a GnRH antagonist. Apoptotic DNA fragmentation in whole testis was measured in rats between 8-70 days of age. A gradual increase (1.8- to 2.0-fold) in testis apoptotic DNA fragmentation was seen in rats between 16-28 days of age, compared with 8-day-old animals, followed by a decrease in adult animals. To study gonadotropin dependence of testicular apoptosis, serum FSH and, to a lesser extent, LH were suppressed by treatment with a long-acting GnRH antagonist (azaline-B, 250 micrograms/kg body wt, two injections at 2-day intervals). Pretreatment with the GnRH antagonist increased apoptotic DNA fragmentation in rats between 16-32 days of age but not in younger and adult animals demonstrating an age-related change in gonadotropin dependence. To identify the exact testis cell type undergoing apoptosis, in situ analysis of DNA fragmentation was performed. In rats at 16-24 days of age, spermatocytes in selected tubules were found to have increased DNA fragmentation. In contrast, neither Leydig cells nor Sertoli cells were affected. In 32-day-old and adult animals, increased DNA fragmentation was seen in early primary spermatocytes of some tubules. Treatment with GnRH antagonist increased the number of cells with DNA fragmentation as well as percentage of tubules affected. In animals between 16-32 days of age, meiotic spermatocytes were labeled, whereas early spermatids were also labeled in 24- and 32-day-old animals. In adult animals, the level of apoptotic DNA fragmentation was not affected by GnRH antagonist treatment. However, DNA isolated from specific stages of the seminiferous tubules of adult animals showed stage-specific changes of apoptotic DNA fragmentation with 2-fold higher levels found in stages I and XII-XIV compared with stage VIII. In situ analysis of adult testis demonstrated that spermatocytes were the major cell type affected. In conclusion, the present study demonstrated that at least three factors determine the onset of apoptosis of the male germ cells: 1) the developmental stage of the animal; 2) serum levels of gonadotropins, especially FSH; and 3) specific stage of the seminiferous epithelial cycle. The present approach provides the basis for future analysis of the role of gonadotropins and other factors in the regulation of testis cell degeneration in normal and pathological states.

Animals↗
PubMed1994

Photoperiod regulates testis cell apoptosis in Djungarian hamsters.

Reproductive activity in the Djungarian hamster is controlled by seasonal variations in day length. Exposure to long days stimulates testis development, while exposure to short days induces testis regression. We recently found that testis regression after gonadotropin deprivation in rats is associated with increases in apoptosis. Here we sought to determine whether or not apoptosis is associated with the testis regression and/or recrudescence that occurs naturally in seasonally breeding mammals. Newborn male hamsters were maintained on long days (16L:8D) until 3 wk of age before being transferred to short days (8L:16D). Following decreases in serum FSH within 3 days of exposure to short days, testis weight decreased by 52% at Day 10, reaching a 70% decrease after 21 days. Analysis of testis cell DNA fragmentation showed a 4.9-fold increase of low-molecular-weight DNA as early as 5 days after transfer to short days; this was followed by a time-dependent decrease. The observed increases in testis cell apoptosis were correlated with decreases in serum testosterone, but decreases in Leydig cell LH receptor content were delayed. In a second study, 6-wk-old hamsters with regressed testes due to a 3-wk exposure to short days were transferred back to long days. After increases in serum FSH within 3 days of photostimulation, a 2-fold elevation in testis weight was found at Day 5. The increase in testis weight was associated with a 65% decrease of testis apoptosis within 5 days of photostimulation. Also, increases in serum testosterone and LH receptor content were observed after 5 and 10 days of exposure to long days, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1994

Hormonal regulation of rat 17 beta-hydroxysteroid dehydrogenase type 1 in cultured rat granulosa cells: effects of recombinant follicle-stimulating hormone, estrogens, androgens, and epidermal growth factor.

Ovarian estradiol (E2) production is regulated by complex interaction of different hormones, such as gonadotropins, steroids, and growth factors. Despite the key role of 17 beta-hydroxysteroid dehydrogenase (17HSD) in E2 biosynthesis, little is known about its regulation in the ovary. Recently, we have characterized the structure of rat 17HSD type 1 and demonstrated that its expression is regulated by gonadotropins and diethylstilbestrol (DES) in rat ovary in vivo. In the present study, the hormonal regulation of 17HSD type 1, and the expression of cytochrome P450 aromatase were examined in parallel in cultured granulosa cells obtained from DES-primed immature rats. Under these conditions, the cells show high expression of 17HSD type 1. Both the enzyme activity and 17HSD type 1 messenger RNA expression in these cells decreased over 2 days of culture in serum-free medium. However, recombinant FSH (recFSH) partially prevented the decreases in enzyme activity and messenger RNA expression in a dose-dependent manner. This effect appears to be mediated by a cAMP-dependent pathway. In contrast to recFSH, neither estrogens (DES or E2) nor androgens (testosterone or dihydrotestosterone) alone affected expression of the enzyme in the cultured cells. However, both estrogens and androgens clearly enhanced the effect of recFSH on 17HSD type 1 expression and 17HSD activity in a dose-dependent manner. Among the growth factors, epidermal growth factor (EGF) has previously been shown to decrease the expression of cytochrome P450 aromatase and E2 biosynthesis in granulosa cells. In the present study, we found that treatment with EGF caused a marked decrease in the effect of recFSH on 17HSD type 1 expression and 17HSD activity. The fact that 17HSD type 1 expression and 17HSD activity always behaved in parallel suggests that 17HSD type 1 is the major 17HSD enzyme involved in estradiol biosynthesis in rat granulosa cells. In conclusion, these data indicate that expression of 17HSD type 1 in rat granulosa cells is under multihormonal regulation. The enzyme is regulated by FSH, via cAMP, and the effect of FSH is modulated by estrogens, androgens, and EGF.

17-Hydroxysteroid Dehydrogenases↗
PubMed1993

Subcutaneous goserelin versus intranasal buserelin for pituitary down-regulation in patients undergoing IVF: a randomized comparative study.

One-hundred women undergoing ovarian stimulation with gonadotrophin-releasing hormone agonist (GnRH-a) and a human menopausal gonadotrophin (HMG) for in-vitro fertilization (IVF) participated in this randomized comparative study. The effectiveness of long-acting s.c. goserelin (Zoladex depot; 49 patients) and intranasally (i.n.) administered buserelin acetate (Suprefact; 51 patients) for pituitary down-regulation was compared. Treatment with s.c. goserelin (3.6 mg) or i.n. buserelin acetate (200 micrograms; 6 times/day) was started on day 21-23 of the cycle. Stimulation with 150 IU of HMG/day was started after at least 11 days of GnRH-a treatment. There were no differences in the time required for follicular development nor in the clinical outcome between groups treated with either goserelin or buserelin. The number of oocytes recovered in the goserelin group was 6.7 +/- 5.0 versus 6.3 +/- 4.9 in the buserelin group. There were 11 pregnancies after the use of goserelin (22.4%) and 12 pregnancies in those given buserelin (24.0%). The number of HMG ampoules needed for follicular maturation was higher in the goserelin group (27.9 +/- 7.8) than in the buserelin group (24.6 +/- 7.8, P < 0.05). The patients given buserelin suffered significantly more from tiredness, depression, headache and abdominal pain than those receiving goserelin, whereas there were no differences between the groups in experiencing mental irritability, nausea and swelling. Subcutaneous goserelin depot injection offers a useful alternative for pituitary down-regulation in IVF stimulation.

Administration, Intranasal↗