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Featured researches published by Jens Fedder.


Cellular Microbiology | 2007

Interleukin‐1 is the initiator of Fallopian tube destruction during Chlamydia trachomatis infection

Malene Hvid; Agata Baczynska; Bent Deleuran; Jens Fedder; Hans Jørgen Knudsen; Gunna Christiansen; Svend Birkelund

Chlamydia trachomatis infection is associated with severe Fallopian tube tissue damage leading to tubal infertility and ectopic pregnancy. To explore the molecular mechanisms behind infection an ex vivo model was established from human Fallopian tubes and examined by scanning electron microscopy and immunohistochemistry. Extensive tissue destruction affecting especially ciliated cells was observed in C. trachomatis infected human Fallopian tube organ culture. Interleukin‐1 (IL‐1) produced by epithelial cells was detected after infection. Addition of IL‐1 receptor antagonist (IL‐1RA) completely eliminated tissue destruction induced by C. trachomatis. The anti‐inflammatory cytokine IL‐10 reduced the damaging effect of C. trachomatis infection, however, to a lesser extent than IL‐1RA. Furthermore, IL‐1 was found to induce IL‐8, a neutrophil attractant, using a signal transduction pathway involving p38 MAP kinase. Consequently, IL‐1 has the potential to generate a cellular infiltrate at the site of infection in vivo. Blocking the IL‐1 receptors by IL‐1RA eliminated tissue destruction and cytokine production. Hence, these studies show the importance of IL‐1 in initiating the tissue destruction observed in the Fallopian tube following C. trachomatis infection. Because leukocytes are absent in the ex vivo model, this study strongly indicates that IL‐1 is the initial proinflammatory cytokine activated by C. trachomatis infection.


Human Reproduction | 2013

Neonatal outcome and congenital malformations in children born after ICSI with testicular or epididymal sperm: a controlled national cohort study

Jens Fedder; A. Loft; Erik T. Parner; Steen Rasmussen; Anja Pinborg

STUDY QUESTION Does neonatal outcome including congenital malformations in children born after ICSI with epididymal and testicular sperm [testicular sperm extraction (TESE)/percutaneous epididymal sperm aspiration (PESA)/testicular sperm aspiration (TESA) (TPT)] differ from neonatal outcome in children born after ICSI with ejaculated sperm, IVF and natural conception (NC)? SUMMARY ANSWER Children born after TPT have similar neonatal outcome, including total malformation rates, as have children born after ICSI and IVF with ejaculated sperm. Testing for variance over the four groups may indicate smaller differences in specific malformation rates with TPT as the highest risk group. WHAT IS KNOWN ALREADY Regarding neonatal outcome as well as congenital malformations in children born after TPT, studies are few, with limited sample size, heterogeneous and often performed without relevant control groups. STUDY DESIGN, SIZE, DURATION Population-based cohort study including all Danish children born after TPT and fresh embryo transfer in Denmark from 1995 to 2009. Children born after transfer of frozen-thawed embryos were excluded. Control groups of children conceived by ICSI with ejaculated sperm, IVF and NC were identified by cross-linkage of the Danish IVF Register, Medical Birth Register (MBR) and National Hospital Discharge Register (HDR). PARTICIPANTS/MATERIALS, SETTING The study group consisted of 466 children born after TPT, while the control groups consisted of 8967 (ICSI with ejaculated sperm), 17 592 (IVF) and 63 854 (NC) children. Neonatal outcomes and congenital malformations were analysed for singletons and twins separately. Risk estimates for low birthweight (LBW, <2500 g) and preterm birth (PTB, <37 gestational weeks) were adjusted for maternal age, parity, child gender and year of childbirth. The study group was identified from the Danish national database on children born after TPT. Control groups were obtained from the IVF register and the MBR. All information included in the study was retrieved from the national registers. MAIN RESULTS AND THE ROLE OF CHANCE Considering singletons and twins as one group, the sex ratio (♂/♀) was significantly lower for children born after TPT (0.89) compared with conventional IVF (1.11; P = 0.017) but did not differ significantly when compared with ICSI with ejaculated sperm (0.94) and NC (1.05). The mean birthweight (BW) for singletons did not differ significantly between groups when including only first-born children. The mean gestational age (GA) in the TPT singletons (279 ± 12 days) was significantly higher compared with IVF (276 ± 18 days; P = 0.02), but similar to ICSI with ejaculated sperm and NC singletons when including only first-born children (277 ± 16 days and 279 ± 14 days, respectively). Rate of stillbirths, perinatal and neonatal mortality in the group of TPT singletons did not differ significantly from any of the control groups. Comparable results were found for the TPT twin group, except for perinatal mortality, which was significantly lower in the TPT group compared with naturally conceived twins. The adjusted risk of LBW was significantly higher for TPT versus NC singletons [adjusted odds ratio (AOR) = 0.67 (0.48-0.93)]; however AOR for PTB was similar in the two groups. Regarding twins, similar adjusted risks were observed for PTB and LBW between the TPT and all three control groups. Significantly more Caesarean sections were performed after IVF (27.3% for singletons) and ICSI (25.1% for singletons) with ejaculated sperm compared with the TPT group (16.4% for singletons). The total rate of congenital malformations in the TPT group was 7.7% and did not differ significantly from any of the control groups. However, singleton TPT boys showed an increased rate of cardiac malformations (3.6%) compared with singleton boys after IVF (1.4%; P = 0.04) and NC (1.1%; P = 0.02). Considering the level of male infertility as a continuum over the four groups, tests for variance in the rate of cardiac malformations in singleton boys, and undescended testicles for singleton as well as twin boys were each significantly increased from NC to IVF to ICSI to TPT (P < 0.001). The rate of hypospadias showed the same pattern, but the TPT group did not differ significantly compared with the control groups. LIMITATIONS, REASONS FOR CAUTION One of the limitations is that the TPT group could not be classified according to testicular or epididymal sperm, as these data were not available in the IVF register. Another limitation is that registry-based studies are encumbered with the risk of reporting or coding errors or missing data due to insufficient coding. However, the quality of data on congenital malformations in HDR has, in other studies, been validated and found acceptable for epidemiological research, and furthermore, recordings on study and control groups are performed similarly. WIDER IMPLICATIONS OF THE FINDINGS Accumulating data show that TPT treatment is equally safe as conventional ICSI and IVF treatment and as NC with regard to neonatal outcome including congenital malformation. STUDY FUNDING/POTENTIAL COMPETING INTERESTS This study is supported by Laboratory of Reproductive Biology, Scientific Unit, Horsens Hospital. No competing interests declared.


Human Reproduction | 2015

Outcomes of transplantations of cryopreserved ovarian tissue to 41 women in Denmark

Annette Klüver Jensen; Stine Gry Kristensen; Kirsten Tryde Macklon; J.V. Jeppesen; Jens Fedder; Erik Ernst; Claus Yding Andersen

STUDY QUESTION What are the results of transplanting cryopreserved ovarian tissue? SUMMARY ANSWER The transplanted ovarian tissue can last up to 10 years, with no relapses following the 53 transplantations, and the chance of a successful pregnancy is currently around one in three for those with a pregnancy-wish. WHAT IS KNOWN ALREADY Cryopreservation of ovarian tissue is now gaining ground as a valid method for fertility preservation. More than 36 children worldwide have now been born following this procedure. STUDY DESIGN, SIZE, DURATION This is a retrospective cohort study of 41 women who had thawed ovarian tissue transplanted 53 times over a period of 10 years, including 1 patient who was lost to follow-up. PARTICIPANTS/MATERIALS, SETTING, METHODS The 41 Danish women, who had in total 53 transplantations, were followed for ovarian function and fertility outcome. Safety was assessed by monitoring relapse in cancer survivors. MAIN RESULTS, AND THE ROLE OF CHANCE Among 32 women with a pregnancy-wish, 10 (31%) had a child/children (14 children in total); this included 1 woman with a third trimester on-going pregnancy. In addition, two legal abortions and one second trimester miscarriage occurred. A total of 24 clinical pregnancies were established in the 32 women with a pregnancy-wish. The tissue remained functional for close to 10 years in some cases and lasted only a short period in others. Three relapses occurred but were unlikely to be due to the transplanted tissue. LIMITATIONS, REASONS FOR CAUTION Self-report through questionnaires with only in-one hospital formalised follow-up of transplanted patients could result in unreported miscarriages. The longevity of the tissue may vary by few months compared with those reported because some patients simply could not remember the date when the tissue became non-functional. WIDER IMPLICATIONS OF THE FINDINGS Cryopreservation of ovarian tissue is likely to become integrated into the treatment of young women, with cancer, who run a risk of losing their fertility. The full functional lifespan of grafts is still being evaluated, because many of the transplanted women have continued to maintain ovarian activity. Some of our first cases have had tissue functioning for ∼ 10 years.


Fertility and Sterility | 2010

Care of women with XY karyotype: a clinical practice guideline

Pernille Bach Jørgensen; Kristín Rós Kjartansdóttir; Jens Fedder

OBJECTIVE To provide an evidence-based guideline for professionals working with XY women. DESIGN Review including patient cases from a Danish fertility clinic. SETTING University-associated scientific unit and fertility clinic. PATIENT(S) Three selected cases. INTERVENTION(S) None. MAIN OUTCOME MEASURE(S) Evaluation of etiology, diagnosis, treatment, and associated disorders in XY women. RESULT(S) Many gene mutations can cause abnormal fetal development leading to androgen insensitivity syndrome or gonadal dysgenesis disorders. Females with these disorders have an XY karyotype but look like girls. They are mostly diagnosed at puberty, and the condition will often lead to serious psychological problems. Increased risk of malignancies and problems with pregnancy and infertility are other aspects that should be considered. This guideline will aid doctors in caring for XY females. CONCLUSION(S) A precise diagnosis is important, because the treatment possibilities (e.g., use of allogenic oocytes) depend on the subgroup to which the XY female belongs.


PLOS ONE | 2011

Identification of Multiple HPV Types on Spermatozoa from Human Sperm Donors

Maja Døvling Kaspersen; Peter B. Larsen; Hans Jakob Ingerslev; Jens Fedder; Gert Bruun Petersen; Jesper Bonde; Per Höllsberg

Human papillomaviruses (HPV) may cause sexually transmitted disease. High-risk types of HPV are involved in the development of cervical cell dysplasia, whereas low-risk types may cause genital condyloma. Despite the association between HPV and cancer, donor sperm need not be tested for HPV according to European regulations. Consequently, the potential health risk of HPV transmission by donor bank sperm has not been elucidated, nor is it known how HPV is associated with sperm. The presence of 35 types of HPV was examined on DNA from semen samples of 188 Danish sperm donors using a sensitive HPV array. To examine whether HPV was associated with the sperm, in situ hybridization were performed with HPV-6, HPV-16 and -18, and HPV-31-specific probes. The prevalence of HPV-positive sperm donors was 16.0% and in 66.7% of these individuals high-risk types of HPV were detected. In 5.3% of sperm donors, two or more HPV types were detected. Among all identified HPV types, 61.9% were high-risk types. In situ hybridization experiments identified HPV genomes particularly protruding from the equatorial segment and the tail of the sperm. Semen samples from more than one in seven healthy Danish donors contain HPV, most of them of high-risk types binding to the equatorial segment of the sperm cell. Most HPV-positive sperm showed decreased staining with DAPI, indicative of reduced content of DNA. Our data demonstrate that oncogenic HPV types are frequent in men.


BMC Microbiology | 2004

Development of real-time PCR for detection of Mycoplasma hominis

Agata Baczynska; Helle Friis Svenstrup; Jens Fedder; Svend Birkelund; Gunna Christiansen

BackgroundMycoplasma hominis is associated with pelvic inflammatory disease, bacterial vaginosis, post partum fever, sepsis and infections of the central nervous system often leading to serious conditions. Association with development of female infertility has also been suggested, but different publications present different results. We developed a sensitive and fast diagnostic real-time PCR to test clinical samples from women undergoing laparoscopic examination before fertility treatment. To develop a test for the detection and quantification of M. hominis we selected a housekeeping gene, glyceraldehyde-3-phosphate dehydrogenase (gap), as a target.ResultsReal-time PCR was optimized to detect 10 copies of M. hominis PG21 genomic DNA. A fluorescence signal was measured for all 20 other M. hominis isolates, and melting curves analysis showed variations in the melting temperature in agreement with sequence variation in the region of the probes. There was no amplification of other mycoplasmal DNA and human DNA. Eighty-three patient cervical swab samples from infertile women were cultured for M. hominis in the BEa medium. Two of the samples (2.4%) were positive after 48 hours of incubation. The real-time PCR detected the same two samples positive, and the DNA concentrations in the clinical specimens were calculated to 37.000 copies/ml and 88.500 copies/ml, respectively.ConclusionThe results demonstrate that real-time PCR may prove to be a rapid alternative to the traditional cultivation method. Information on bacterial load in genital swabs can be obtained. The assay allowed detection of M. hominis in a closed system reducing the risk of contamination by amplicon carry-over.


Clinical Endocrinology | 2008

Left ventricular dysfunction in Klinefelter syndrome is associated to insulin resistance, abdominal adiposity and hypogonadism

Niels Holmark Andersen; Anders Bojesen; Kurt Kristensen; Niels H. Birkebaek; Jens Fedder; Paul Bennett; Jens Sandahl Christiansen; Claus Højbjerg Gravholt

Objective  Epidemiological data suggest there is an increased risk of dying from heart disease among patients with Klinefelter syndrome (KS). Due to high prevalence of hypogonadism and metabolic syndrome, we speculated that patients with KS may have subclinical changes in the left ventricular function. Therefore, the aim was to assess left ventricular long axis function by tissue Doppler echocardiography in patients with KS and relate these findings to the metabolic status and testosterone levels.


NeuroImage: Clinical | 2014

Neuroanatomical correlates of Klinefelter syndrome studied in relation to the neuropsychological profile

Anne Skakkebæk; Claus Højbjerg Gravholt; Peter Mondrup Rasmussen; Anders Bojesen; Jens Søndergaard Jensen; Jens Fedder; Peter Laurberg; Jens Michael Hertz; John R. Østergaard; Anders Degn Pedersen; Mikkel Wallentin

Brain imaging in Klinefelter syndrome (47, XXY) (KS), a genetic disorder characterized by the presence of an extra X chromosome, may contribute to understanding the relationship between gene expression, brain structure, and subsequent cognitive disabilities and psychiatric disorders. We conducted the largest to date voxel-based morphometry study of 65 KS subjects and 65 controls matched for age and education and correlated these data to neuropsychological test scores. The KS patients had significantly smaller total brain volume (TBV), total gray matter volume (GMV) and total white matter volume (WMV) compared to controls, whereas no volumetric difference in cerebral spinal fluid (CSF) was found. There were no differences in TBV, GMV, WMV or CSF between testosterone treated KS (T-KS) and untreated KS (U-KS) patients. Compared to controls, KS patients had significantly decreased GMV bilaterally in insula, putamen, caudate, hippocampus, amygdala, temporal pole and frontal inferior orbita. Additionally, the right parahippocampal region and cerebellar volumes were reduced in KS patients. KS patients had significantly larger volumes in right postcentral gyrus, precuneus and parietal regions. Multivariate classification analysis discriminated KS patients from controls with 96.9% (p < 0.001) accuracy. Regression analyses, however, revealed no significant association between GMV differences and cognitive and psychological factors within the KS patients and controls or the groups combined. These results show that although gene dosage effect of having and extra X-chromosome may lead to large scale alterations of brain morphometry and extended cognitive disabilities no simple correspondence links these measures.


Systems Biology in Reproductive Medicine | 2008

Prevalence of Mycoplasma genitalium, Mycoplasma hominis and Chlamydia trachomatis among Danish patients requesting abortion.

Agata Baczynska; Malene Hvid; Philippe Lamy; Svend Birkelund; Gunna Christiansen; Jens Fedder

The aim of the study was to determine lower genital tract carriage rate of Mycoplasma genitalium (M. genitalium) and to compare it to the carriage rates of Mycoplasma hominis (M. hominis ) and Chlamydia trachomatis (C. trachomatis) among 102 women requesting termination of pregnancy at the Horsens Hospital in Denmark. Real-Time PCR was used for the detection of bacterial DNA, and the presence of antibodies to the three microorganisms was determined by ELISA and immunoblotting. Real-Time PCR detected M. genitalium in one swab sample (0.98%) only, while the prevalence of C. trachomatis was high (15.69%) and M. hominis colonization (18.63%) was similar to colonization observed among sexually experienced adults. There was a significant difference in prevalence of M. hominis infection in the different age groups. C. trachomatis load in the cervical samples was significantly higher among young patients. There was no correlation between the presence of genital infection with C. trachomatis and genital mycoplasmas and no correlation between the presence of antibodies to these bacteria. In conclusion, in Danish patients it is not necessary to test for M. genitalium before abortion since less than 1% were found positive. The prevalence of genital C. trachomatis infections was high among the abortion-seeking patients.


Journal of Andrology | 2013

Retrograde ejaculation and sexual dysfunction in men with diabetes mellitus: a prospective, controlled study

Jens Fedder; Maja Døvling Kaspersen; I Brandslund; Astrid Ditte Højgaard

Retrograde ejaculation (RE) and erectile dysfunction may be caused by diabetes mellitus (DM), but the prevalence of RE among DM patients is unknown. A prospective, blinded case–control study comparing men with DM with matched controls according to RE and erectile dysfunction was performed. Twenty‐seven men with DM matched the inclusion criteria and agreed to participate in the study, and of these 26 delivered an ejaculate. We were able to recruit 18 matching controls, and of these 16 delivered an ejaculate.

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Bente Mertz Nørgård

University of Southern Denmark

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Sonia Friedman

Brigham and Women's Hospital

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