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Featured researches published by Jørgen Holm Petersen.


Environmental Health Perspectives | 2006

Human breast milk contamination with phthalates and alterations of endogenous reproductive hormones in infants three months of age.

Katharina M. Main; Gerda K. Mortensen; Marko Kaleva; Kirsten A. Boisen; Ida N. Damgaard; Marla Chellakooty; Ida M. Schmidt; Anne-Maarit Suomi; Helena E. Virtanen; Jørgen Holm Petersen; Anna-Maria Andersson; Jorma Toppari; Niels E. Skakkebæk

Phthalates adversely affect the male reproductive system in animals. We investigated whether phthalate monoester contamination of human breast milk had any influence on the postnatal surge of reproductive hormones in newborn boys as a sign of testicular dysgenesis. Design We obtained biologic samples from a prospective Danish–Finnish cohort study on cryptorchidism from 1997 to 2001. We analyzed individual breast milk samples collected as additive aliquots 1–3 months postnatally (n = 130; 62 cryptorchid/68 healthy boys) for phthalate monoesters [mono-methyl phthalate (mMP), mono-ethyl phthalate (mEP), mono-n-butyl phthalate (mBP), mono-benzyl phthalate (mBzP), mono-2-ethylhexyl phthalate (mEHP), mono-isononyl phthalate (miNP)]. We analyzed serum samples (obtained in 74% of all boys) for gonadotropins, sex-hormone binding globulin (SHBG), testosterone, and inhibin B. Results All phthalate monoesters were found in breast milk with large variations [medians (minimum–maximum)]: mMP 0.10 (< 0.01–5.53 μg/L), mEP 0.95 (0.07–41.4 μg/L), mBP 9.6 (0.6–10,900 μg/L), mBzP 1.2 (0.2–26 μg/L), mEHP 11 (1.5–1,410 μg/L), miNP 95 (27–469 μg/L). Finnish breast milk had higher concentrations of mBP, mBzP, mEHP, and Danish breast milk had higher values for miNP (p = 0.0001–0.056). No association was found between phthalate monoester levels and cryptorchidism. However, mEP and mBP showed positive correlations with SHBG (r = 0.323, p = 0.002 and r = 0.272, p = 0.01, respectively); mMP, mEP, and mBP with LH:free testosterone ratio (r = 0.21–0.323, p = 0.002–0.044) and miNP with luteinizing hormone (r = 0.243, p = 0.019). mBP was negatively correlated with free testosterone (r = −0.22, p = 0.033). Other phthalate monoesters showed similar but nonsignificant tendencies. Conclusions Our data on reproductive hormone profiles and phthalate exposures in newborn boys are in accordance with rodent data and suggest that human Leydig cell development and function may also be vulnerable to perinatal exposure to some phthalates. Our findings are also in line with other recent human data showing incomplete virilization in infant boys exposed to phthalates prenatally.


Pediatrics | 2009

Recent Decline in Age at Breast Development: The Copenhagen Puberty Study

Lise Aksglaede; Kaspar Sørensen; Jørgen Holm Petersen; Niels E. Skakkebæk; Anders Juul

OBJECTIVE. Recent publications showing unexpectedly early breast development in American girls created debate worldwide. However, secular trend analyses are often limited by poor data comparability among studies performed by different researchers in different time periods and populations. Here we present new European data systematically collected from the same region and by 1 research group at the beginning and end of the recent 15-year period. METHODS. Girls (N = 2095) aged 5.6 to 20.0 years were studied in 1991–1993 (1991 cohort; n = 1100) and 2006–2008 (2006 cohort; n = 995). All girls were evaluated by palpation of glandular breast, measurement of height and weight, and blood sampling (for estradiol, luteinizing hormone, and follicle-stimulating hormone). Age distribution at entering pubertal breast stages 2 through 5, pubic hair stages 2 through 5, and menarche was estimated for the 2 cohorts. RESULTS. Onset of puberty, defined as mean estimated age at attainment of glandular breast tissue (Tanner breast stage 2+), occurred significantly earlier in the 2006 cohort (estimated mean age: 9.86 years) when compared with the 1991 cohort (estimated mean age: 10.88 years). The difference remained significant after adjustment for BMI. Estimated ages at menarche were 13.42 and 13.13 years in the 1991 and 2006 cohorts, respectively. Serum follicle-stimulating hormone and luteinizing hormone did not differ between the 2 cohorts at any age interval, whereas significantly lower estradiol levels were found in 8- to 10-year-old girls from the 2006 cohort compared with similarly aged girls from the 1991 cohort. CONCLUSIONS. We found significantly earlier breast development among girls born more recently. Alterations in reproductive hormones and BMI did not explain these marked changes, which suggests that other factors yet to be identified may be involved.


Environmental Health Perspectives | 2006

Persistent Pesticides in Human Breast Milk and Cryptorchidism

Ida N. Damgaard; Niels E. Skakkebæk; Jorma Toppari; Helena E. Virtanen; Heqing Shen; Karl-Werner Schramm; Jørgen Holm Petersen; Tina Kold Jensen; Katharina M. Main

Introduction Prenatal exposure to some pesticides can adversely affect male reproductive health in animals. We investigated a possible human association between maternal exposure to 27 organochlorine compounds used as pesticides and cryptorchidism among male children. Design Within a prospective birth cohort, we performed a case–control study; 62 milk samples from mothers of cryptorchid boys and 68 from mothers of healthy boys were selected. Milk was collected as individual pools between 1 and 3 months postpartum and analyzed for 27 organochlorine pesticides. Results Eight organochlorine pesticides were measurable in all samples (medians; nanograms per gram lipid) for cases/controls: 1,1-dichloro-2,2-bis(4-chlorophenyl)ethylene (p,p′-DDE): 97.3/83.8; β-hexachlorocyclohexane (β-HCH): 13.6/12.3; hexachlorobenzene (HCB): 10.6/8.8; α -endosulfan: 7.0/6.7; oxychlordane: 4.5/4.1; 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (p,p′-DDT): 4.6/4.0; dieldrin: 4.1/3.1; cis-heptachloroepoxide (cis-HE): 2.5/2.2. Five compounds [octachlorostyrene (OCS); pentachlorobenzene, 1,1-dichloro-2,2-bis(4-chlorophenyl)ethane (p,p′-DDD); o,p′-DDT; mirex] were measurable in most samples (detection rates 90.8–99.2%) but in lower concentrations. For methoxychlor, cis-chlordane, pentachloroanisole (PCA), γ -HCH, 1,1-dichloro-2-(2-chlorophenyl)-2,2(4-chlorophenyl)ethane, trans-chlordane, α -HCH, and o,p′-DDE, both concentrations and detection rates were low (26.5–71.5%). Heptachlor, HCH (δ, ɛ ), aldrin, β-endosulfan and trans-heptachloroepoxide were detected at negligible concentrations and low detection rates and were not analyzed further. Seventeen of 21 organochlorine pesticides [p,p′-DDT, p,p′-DDE, p,p′-DDD, o,p′-DDT, HCH (α , β, γ ), HCB, PCA, α -endosulfan, cis-HE, chlordane (cis-, trans-) oxychlordane, methoxychlor, OCS, and dieldrin] were measured in higher median concentrations in case milk than in control milk. Apart from trans-chlordane (p = 0.012), there were no significant differences between cryptorchid and healthy boys for individual chemicals. However, combined statistical analysis of the eight most abundant persistent pesticides showed that pesticide levels in breast milk were significantly higher in boys with cryptorchidism (p = 0.032). Conclusion The association between congenital cryptorchidism and some persistent pesticides in breast milk as a proxy for maternal exposure suggests that testicular descent in the fetus may be adversely affected.


The Journal of Clinical Endocrinology and Metabolism | 2010

Recent Changes in Pubertal Timing in Healthy Danish Boys: Associations with Body Mass Index

Kaspar Sørensen; Lise Aksglaede; Jørgen Holm Petersen; Anders Juul

CONTEXT In the 1990s, the American population-based study NHANES III renewed the focus on possible secular trends in male puberty. However, no conclusions could be made on pubertal onset due to the lack of compatible data. OBJECTIVE The aim of the study was to evaluate secular trends in pubertal onset during the recent 15 yr and their relation to body mass index (BMI) in boys. DESIGN AND SETTING We conducted a cross-sectional study in 1991-1993 and a combined cross-sectional and longitudinal study in 2006-2008 (The Copenhagen Puberty Study) at a tertiary center for pediatric endocrinology. PARTICIPANTS A total of 1528 boys aged 5.8 to 19.9 yr participated (n = 824 in 1991-1993, and n = 704 in 2006-2008). Genital and pubic hair stages as well as testicular volume by orchidometry were evaluated. Blood samples were analyzed for LH, FSH, testosterone, and SHBG. MAIN OUTCOME MEASURES We measured age at onset of pubertal markers. RESULTS Onset of puberty, defined as age at attainment of testicular volume above 3 ml, occurred significantly earlier in 2006-2008 [11.66 yr (11.49-11.82); mean (95% confidence interval)] than in 1991-1993 [11.92 yr (11.76-12.08); P = 0.025]. Significantly higher LH, but not testosterone, levels were found in the 11- to 16-yr-old boys from 2006-2008 compared to 1991-1993 (P = 0.020). BMI Z-score increased significantly from 1991-1993 [0.044 (-0.016 to 0.104)] to 2006-2008 [0.290 (0.219-0.361); P < 0.001]. Interestingly, pubertal onset and LH levels were no longer significantly different between study periods after adjustment for BMI. CONCLUSIONS Estimated mean age at onset of puberty has declined significantly during the recent 15 yr. This decline was associated with the coincident increase in BMI.


BMJ Open | 2012

Human semen quality in the new millennium: a prospective cross-sectional population-based study of 4867 men

Niels Jørgensen; Ulla Nordström Joensen; Tina Kold Jensen; Martin Blomberg Jensen; Kristian Almstrup; Inge A. Olesen; Anders Juul; Anna-Maria Andersson; Elisabeth Carlsen; Jørgen Holm Petersen; Jorma Toppari; Niels E. Skakkebæk

Objectives Considerable interest and controversy over a possible decline in semen quality during the 20th century raised concern that semen quality could have reached a critically low level where it might affect human reproduction. The authors therefore initiated a study to assess reproductive health in men from the general population and to monitor changes in semen quality over time. Design Cross-sectional study of men from the general Danish population. Inclusion criteria were place of residence in the Copenhagen area, and both the man and his mother being born and raised in Denmark. Men with severe or chronic diseases were not included. Setting Danish one-centre study. Participants 4867 men, median age 19 years, included from 1996 to 2010. Outcome measures Semen volume, sperm concentration, total sperm count, sperm motility and sperm morphology. Results Only 23% of participants had optimal sperm concentration and sperm morphology. Comparing with historic data of men attending a Copenhagen infertility clinic in the 1940s and men who recently became fathers, these two groups had significantly better semen quality than our study group from the general population. Over the 15 years, median sperm concentration increased from 43 to 48 million/ml (p=0.02) and total sperm count from 132 to 151 million (p=0.001). The median percentage of motile spermatozoa and abnormal spermatozoa were 68% and 93%, and did not change during the study period. Conclusions This large prospective study of semen quality among young men of the general population showed an increasing trend in sperm concentration and total sperm count. However, only one in four men had optimal semen quality. In addition, one in four will most likely face a prolonged waiting time to pregnancy if they in the future want to father a child and another 15% are at risk of the need of fertility treatment. Thus, reduced semen quality seems so frequent that it may impair the fertility rates and further increase the demand for assisted reproduction.


Annals of the Rheumatic Diseases | 2000

A prospective study of vasculitis patients collected in a five year period: evaluation of the Chapel Hill nomenclature.

Søren Freiesleben Sørensen; Ole Slot; Niels Tvede; Jørgen Holm Petersen

OBJECTIVE To test the usefulness of the Chapel Hill nomenclature, supplemented with surrogate parameters, as diagnostic criteria for primary vasculitides. METHODS To prospectively evaluate vasculitis patients according to a standardised clinical and para-clinical programme. In accordance with the Chapel Hill publication surrogate parameters were used: proteinuria, haematuria and red blood cell casts (glomerulonephritis), angiographic or ultrasonic demonstration of aneurysms or stenoses (arteritis), radiological lung infiltrates or cavitations of more than one months duration (granuloma in the lungs), bloody nasal discharge or crusts, chronic sinusitis, otitis and/or mastoiditis, bone and/or cartilage destruction, and acute hearing loss (granuloma in upper airways). RESULTS The following entities were diagnosed: giant cell arteritis (n=14), Takayasu arteritis (n=1), polyarteritis nodosa (n=2), Wegeners granulomatosis (n=27), Churg-Strauss syndrome (n=2), microscopic polyangiitis (n=12), Henoch-Schönlein purpura (n=2), cutaneous leucocytoclastic angiitis (n=37), and secondary vasculitis (n=21). Giant cell arteritis and cutaneous leucocytoclastic angiitis were in all cases diagnosed by biopsy. Using the Chapel Hill nomenclature supplemented with surrogate parameters, only 8 of 27 patients were diagnosed with Wegeners granulomatosis, and 3 of 12 cases with microscopic polyangiitis. The number of patients in the remaining diagnostic entities were considered to few to evaluate. CONCLUSIONS The Chapel Hill nomenclature, supplemented with surrogate parameters, failed to act as diagnostic criteria in Wegeners granulomatosis and microscopic polyangiitis. The following diagnostic criteria are proposed for Wegeners granulomatosis: (1) Biopsy or surrogate parameter for granulomatous inflammation in the respiratory system and (2) Biopsy verified necrotising vasculitis in small to medium sized vessels or biopsy/surrogate parameter for glomerulonephritis or positive PR3-ANCA test and (3) Lack of eosinophilia in blood and biopsy samples. The following diagnostic criteria are proposed for microscopic polyangiitis: (1) Biopsy verified necrotising vasculitis in small vessels and/or glomerulonephritis with few or no immune deposits and (2) Involvement of more than one organ system as indicated by biopsy verified vasculitis in small to medium sized vessels or surrogate parameter for glomerulonephritis and (3) Lack of biopsy and surrogate parameter for granulomatous inflammation in the respiratory system. Using these criteria all Wegeners patients and 9 of 12 patients with microscopic polyangiitis could be diagnosed.


The Journal of Clinical Endocrinology and Metabolism | 2010

Changes in Anti-Müllerian Hormone (AMH) throughout the Life Span: A Population-Based Study of 1027 Healthy Males from Birth (Cord Blood) to the Age of 69 Years

Lise Aksglaede; Kaspar Sørensen; Malene Boas; Annette Mouritsen; Casper P. Hagen; Rikke Bodin Jensen; Jørgen Holm Petersen; Allan Linneberg; A.-M. Andersson; K. M. Main; Niels Erik Skakkebæk; Anders Juul

CONTEXT Anti-Müllerian hormone (AMH), which is secreted by immature Sertoli cells, triggers the involution of the fetal Müllerian ducts. AMH is a testis-specific marker used for diagnosis in infants with ambiguous genitalia or bilateral cryptorchidism. AIM The aim of the study was to describe the ontogeny of AMH secretion through life in healthy males. SETTING This was a population-based study of healthy volunteers. PARTICIPANTS PARTICIPANTS included 1027 healthy males from birth (cord blood) to 69 yr. A subgroup was followed up longitudinally through the infantile minipuberty [(in cord blood, and at 3 and 12 months), n=55] and another group through puberty [(biannual measurements), n=83]. MAIN OUTCOME MEASURES Serum AMH was determined by a sensitive immunoassay. Serum testosterone, LH, and FSH were measured, and pubertal staging was performed in boys aged 6 to 20 yr (n=616). RESULTS Serum AMH was above the detection limit in all samples with a marked variation according to age and pubertal status. The median AMH level in cord blood was 148 pmol/liter and increased significantly to the highest observed levels at 3 months (P<0.0001). AMH declined at 12 months (P<0.0001) and remained at a relatively stable level throughout childhood until puberty, when AMH declined progressively with adults exhibiting 3-4% of infant levels. CONCLUSION Based on this extensive data set, we found detectable AMH serum levels at all ages, with the highest measured levels during infancy. At the time of puberty, AMH concentrations declined and remained relatively stable throughout adulthood. The potential physiological role of AMH and clinical applicability of AMH measurements remain to be determined.


Human Reproduction | 2011

Intrauterine exposure to mild analgesics is a risk factor for development of male reproductive disorders in human and rat

David Møbjerg Kristensen; Ulla Hass; Laurianne Lesné; Grete Lottrup; Pernille Rosenskjold Jacobsen; Christèle Desdoits-Lethimonier; Julie Boberg; Jørgen Holm Petersen; Jorma Toppari; Tina Kold Jensen; Søren Brunak; Niels E. Skakkebæk; Christine Nellemann; Katharina M. Main; Bernard Jégou; Henrik Leffers

BACKGROUND More than half of pregnant women in the Western world report intake of mild analgesics, and some of these drugs have been associated with anti-androgenic effects in animal experiments. Intrauterine exposure to anti-androgens is suspected to contribute to the recent increase in male reproductive problems, and many of the anti-androgenic compounds are like the mild analgesics potent inhibitors of prostaglandin synthesis. Therefore, it appears imperative to further investigate the potential endocrine disrupting properties of mild analgesics. METHODS In a prospective birth cohort study, 2297 Danish and Finnish pregnant women completed a questionnaire and 491 of the Danish mothers participated in a telephone interview, reporting on their use of mild analgesics during pregnancy. The testicular position of newborns was assessed by trained paediatricians. In rats, the impact of mild analgesics on anogenital distance (AGD) after intrauterine exposure was examined together with the effect on ex vivo gestational day 14.5 testes. RESULTS In the Danish birth cohort, the use of mild analgesics was dose-dependently associated with congenital cryptorchidism. In particular, use during the second trimester increased the risk. This risk was further increased after the simultaneous use of different analgesics. The association was not found in the Finnish birth cohort. Intrauterine exposure of rats to paracetamol led to a reduction in the AGD and mild analgesics accordingly reduced testosterone production in ex vivo fetal rat testes. CONCLUSION There was an association between the timing and the duration of mild analgesic use during pregnancy and the risk of cryptorchidism. These findings were supported by anti-androgenic effects in rat models leading to impaired masculinization. Our results suggest that intrauterine exposure to mild analgesics is a risk factor for development of male reproductive disorders.


Journal of Clinical Oncology | 2002

Effect of graded testicular doses of radiotherapy in patients treated for carcinoma-in-situ in the testis

Peter Meidahl Petersen; Aleksander Giwercman; Gedske Daugaard; Mikael Rørth; Jørgen Holm Petersen; Niels E. Skakkebæk; Steen W. Hansen; Hans von der Maase

PURPOSE To determine the effect of radiotherapy in doses 14 to 20 Gy on eradication of carcinoma-in-situ (CIS) testis and on the Leydig cell function. PATIENTS AND METHODS Forty-eight patients presented with unilateral testicular germ cell cancer and CIS of the contralateral testis. The CIS-bearing testis was treated with daily irradiation doses of 2 Gy, 5 days a week, to a cumulative dose of 20 Gy (21 patients), 18 Gy (three patients), 16 Gy (10 patients), and 14 Gy (14 patients). RESULTS All patients treated at dose levels 20 Gy to 16 Gy achieved histologically verified complete remission without signs of recurrence of CIS after an observation period of more than 5 years. One of 14 patients treated at dose level 14 Gy had a relapse of CIS 20 months after irradiation. Leydig cell function was examined before and regularly after radiotherapy in 44 of 48 patients. The levels of testosterone were lower after radiotherapy than before. Testosterone showed a stable decrease for more than 5 years after treatment (3.6% per year) without dose dependency. The levels of luteinizing hormone and follicle-stimulating hormone were increased after radiotherapy. The need of androgen substitution therapy was similar at all dose levels. CONCLUSION Testicular irradiation is a safe treatment at dose level 20 Gy (10 x 2 Gy). Decrease of dose to 14 Gy (7 x 2 Gy) might lead to risk of relapse of CIS. Impairment of hormone production without clinically significant dose dependency is seen in the dose range 14 to 20 Gy.


Human Reproduction | 2011

Vitamin D is positively associated with sperm motility and increases intracellular calcium in human spermatozoa

Martin Blomberg Jensen; Poul J. Bjerrum; Torben E. Jessen; John Nielsen; Ulla Nordström Joensen; Inge A. Olesen; Jørgen Holm Petersen; Anders Juul; Steen Dissing; Niels Jørgensen

BACKGROUND The vitamin D receptor (VDR) is expressed in human spermatozoa, and VDR-knockout mice and vitamin D (VD) deficiency in rodents results in impaired fertility, low sperm counts and a low number of motile spermatozoa. We investigated the role of activated VD (1,25(OH)(2)D(3)) in human spermatozoa and whether VD serum levels are associated with semen quality. METHODS Cross-sectional association study of semen quality and VD serum level in 300 men from the general population, and in vitro studies on spermatozoa from 40 men to investigate the effects of VD on intracellular calcium, sperm motility and acrosome reaction. All men delivered samples for routine semen analysis and blood for measurements of follicle stimulating hormone, Inhibin B, 25-hydroxy-VD, albumin, alkaline phosphatase, calcium and parathyroid hormone (PTH). RESULTS In the association study, 44% were VD insufficient (<50 nM), and VD was inversely correlated with PTH (P < 0.0005). VD serum levels correlated positively with sperm motility and progressive motility (P < 0.05), and men with VD deficiency (<25 nM) had a lower proportion of motile (P = 0.027), progressive motile (P = 0.035) and morphologically normal spermatozoa (P = 0.044) compared with men with high VD levels (>75 nM). 1,25(OH)(2)D(3) increased intracellular calcium concentration in human spermatozoa through VDR-mediated calcium release from an intracellular calcium storage, increased sperm motility and induced the acrosome reaction in vitro. CONCLUSIONS 1,25(OH)(2)D(3) increased intracellular calcium concentration, sperm motility and induced the acrosome reaction in mature spermatozoa, and VD serum levels were positively associated with sperm motility, suggesting a role for VD in human sperm function.

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Anders Juul

University of Copenhagen

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Tina Kold Jensen

University of Southern Denmark

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Allan Krasnik

University of Copenhagen

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Marie Norredam

University of Copenhagen

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