Erik Ernst - Academia.edu (original) (raw)
Papers by Erik Ernst
Fertility and Sterility, 2012
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Cryopreservation of ovarian tissue is a promising new technique for fertility preservation in pat... more Cryopreservation of ovarian tissue is a promising new technique for fertility preservation in patients facing gonadotoxic treatment. Ovarian tissue is extracted and cryo-stored at low temperature prior to treatment. If the woman becomes menopausal, the tissue can be transplanted and a few months later the woman will start to ovulate and be able to conceive, naturally or with assisted reproduction treatment. Currently, 12 healthy children have been born worldwide as a result of transplanting frozen/thawed ovarian tissue. Of these children 3 are Danish and a number of other Danish women are currently attempting to become pregnant. One of these women conceived naturally and had a normal intrauterine pregnancy following transplantation of cryopreserved ovarian tissue. However, the woman decided to terminate the pregnancy within the legal time frame. This pregnancy imposes cryopreservation of ovarian tissue for fertility preservation as a valid method and illustrates that personal life circumstances may rapidly change.
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Fertility and Sterility, 2012
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The Histochemical journal, 1997
The autometallographic technique was used to demonstrate the localization of mercury in dorsal ro... more The autometallographic technique was used to demonstrate the localization of mercury in dorsal root ganglia of adult Wistar rats. The animals were either exposed to mercury vapour, 100 micrograms Hg m-3, 6 h day-1, 5 days per week, or treated with organic mercury in the drinking water, 20 mg CH3HgCl per litre, for 4 weeks. The effect of orally administered sodium selenite on the pattern of intracellular distribution of mercury in these two situations was investigated. In rats exposed to mercury vapour alone, faint staining was present in ganglion cells. The selenite induced a conspicuous increase in the number of stained cells and in the intracellular staining intensity. In rats treated with organic mercury, mercury deposits were detected within ganglion cells and macrophages. The number of mercury-containing cells was increased by co-administration of selenite. In addition, satellite cells, the capsule and vessel walls were faintly stained. Twenty weeks after cessation of the organ...
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The Histochemical journal, 1998
A concept for the computer-assisted visualization of tubular organs is presented. Unmarked histol... more A concept for the computer-assisted visualization of tubular organs is presented. Unmarked histological zinc-stained serial sections from the epididymis of the Wistar rat were aligned to demonstrate the concept. Virtual images were made through the aligned sections and served as controls for the alignment process. Animation of the serial sections and the virtual images revealed new information about the structure of the organ under investigation. The analysis was used to upgrade the anatomical knowledge of rat epididymis by describing how the epididymal duct runs through the structure. The proximal parts of the epididymis contain large communicating septa of connective tissue dividing the caput and the upper part of the corpus epididymidis into segments. The tortuousness was high in the caput with many turns within a small area of the epididymis, whereas longer loops were found in the lower part of the corpus and cauda epididymidis. The tube of the vas deferens was found to become a...
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The Prostate, 1997
The prostate contains high amounts of free zinc ions which are excreted into the seminal fluid. T... more The prostate contains high amounts of free zinc ions which are excreted into the seminal fluid. The extra- and intracellular distribution of zinc ions using the highly specific autometallographical (AMG) method is described. Prostates from sulfide-perfused rats were excised, and the ZnS crystals were silver-enhanced to sizes detectable by the electron and light microscope. AMGZnS grains were found primarily in the acinic lumen of the lateral lobes. The dorsal lobe stained only faintly, while the ventral lobe was void of grains. At ultrastructural levels, the presence of zinc ions was confined to apical secretory vesicles and lysosome-like structure of the epithelium of mainly the lateral lobes. We suggest a constant secretion of zinc ions from the epithelial cells into both the acinar lumen and the intercellular canaliculi, and that the zinc enriched secretory cells in the prostate belong to a system of glandular cells that uses zinc ions to aggregate macromolecules to be excreted.
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Reproductive BioMedicine Online, 2014
Cryopreservation of ovarian tissue is one way of preserving fertility in young women with a malig... more Cryopreservation of ovarian tissue is one way of preserving fertility in young women with a malignant disease or other disorders that require gonadotoxic treatment. The purpose of the study was to explore how many women remained interested in continued cryostorage of their ovarian tissue beyond an initial 5-year period. Between 1999 and 2006, a total of 201 girls and young women had one ovary cryopreserved for fertility preservation in Denmark. One hundred of these met our inclusion criteria, which included a follow-up period of at least 5 years, and were mailed a questionnaire. The response rate was 95%. Sixteen of the patients (17%) stated that they wanted disposal of their tissue; the main reason was completion of family (63%). The mean age of those requesting disposal was 36.6 years, whereas those still wanting their tissue stored were significantly younger, with a mean age of 33.0 years (P < 0.008). In conclusion, most women with ovarian tissue cryobanked requested continued cryostorage after an initial period of at least 5 years. The main reason for requesting disposal was successful completion of a family.
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The Lancet, 2015
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Reproductive Toxicology, 1998
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Advances in Experimental Medicine and Biology, 2003
SwePub titelinformation: Epidemiologic evidence on biological and environmental male factors in e... more SwePub titelinformation: Epidemiologic evidence on biological and environmental male factors in embryonic loss.
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Scandinavian Journal of Urology and Nephrology, 1993
The incidence of asymptomatic varicocele among 542 unselected military conscripts in Denmark was ... more The incidence of asymptomatic varicocele among 542 unselected military conscripts in Denmark was 9%. Semen from 39 of the 49 men with varicocele was compared with findings in age-matched, varicocele-free controls. The overall quality of the semen was reduced in the varicocele group (p < 0.001), with significantly lower parameters of sperm concentration, total sperm count, qualitative motility and sperm motility after 24 hours. There was also significant difference in morphology, with more amorphous spermatozoa and more with tail defects (p < 0.05) in the varicocele group. The study indicated an association between asymptomatic varicocele and compromised sperm quality. The advisability of surgical treatment was not clarified, but the two groups of men will be further observed with special regard to this question.
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Reproductive Toxicology, 1998
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Reproductive Toxicology, 1998
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Reproductive Toxicology, 2002
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Reproductive Toxicology, 2002
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Reproductive Toxicology, 1998
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Reproductive BioMedicine Online, 2011
This paper presents the Danish 10-year experience (1999-2009) with cryopreservation (n=386) and a... more This paper presents the Danish 10-year experience (1999-2009) with cryopreservation (n=386) and autotransplantation of ovarian tissue (n=18). Before applying the technique to humans, the method was thoroughly tested and validated. The cryoprotectant solution was chosen after histological evaluation of mouse and human ovarian tissue after freezing with four different combinations of cryoprotectants. Viability was confirmed by transplantation of frozen-thawed human ovarian tissue (n=49) to oophorectomized Nude mice. Viability after transport of fresh tissue 4-5h prior to freezing had previously been validated. Overnight transport of fresh ovarian tissue prior to cryopreservation was evaluated when human ovarian tissue was kept on ice for 20h and then cryopreserved. The thawed ovarian tissue was transplanted to an oophorectomized Nude mouse and histology confirmed viability. In Denmark 12 women have received a total of 18 autotransplantations of ovarian tissue. All women resumed ovarian function and three healthy babies were born to two women. In both women, the tissue was transported on ice for 4-5h prior to cryopreservation. Ovarian tissue cryopreservation is an important method for fertility preservation; however, before applying the method clinically, each laboratory should perform thorough validation of their technique.
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PEDIATRICS, 2006
Our aim was to assess the incidence of cerebral palsy among children conceived with in vitro fert... more Our aim was to assess the incidence of cerebral palsy among children conceived with in vitro fertilization and children conceived without in vitro fertilization. A population-based, cohort study, including all live-born singletons and twins born in Denmark between January 1, 1995, and December 31, 2000, was performed. Children conceived with in vitro fertilization (9255 children) were identified through the In Vitro Fertilization Register; children conceived without in vitro fertilization (394,713) were identified through the Danish Medical Birth Register. Cerebral palsy diagnoses were obtained from the National Register of Hospital Discharges. The main outcome measure was the incidence of cerebral palsy in the in vitro fertilization and non-in vitro fertilization groups. Children born after in vitro fertilization had an increased risk of cerebral palsy; these results were largely unchanged after adjustment for maternal age, gender, parity, small-for-gestational age status, and educational level. The independent effect of in vitro fertilization vanished after additional adjustment for multiplicity or preterm delivery. When both multiplicity and preterm delivery were included in the multivariate models, preterm delivery remained associated strongly with the risk of cerebral palsy. The large proportions of preterm deliveries with in vitro fertilization, primarily for twins but also for singletons, pose an increased risk of cerebral palsy.
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Obstetrical & Gynecological Survey, 2009
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Fertility and Sterility, 2012
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Cryopreservation of ovarian tissue is a promising new technique for fertility preservation in pat... more Cryopreservation of ovarian tissue is a promising new technique for fertility preservation in patients facing gonadotoxic treatment. Ovarian tissue is extracted and cryo-stored at low temperature prior to treatment. If the woman becomes menopausal, the tissue can be transplanted and a few months later the woman will start to ovulate and be able to conceive, naturally or with assisted reproduction treatment. Currently, 12 healthy children have been born worldwide as a result of transplanting frozen/thawed ovarian tissue. Of these children 3 are Danish and a number of other Danish women are currently attempting to become pregnant. One of these women conceived naturally and had a normal intrauterine pregnancy following transplantation of cryopreserved ovarian tissue. However, the woman decided to terminate the pregnancy within the legal time frame. This pregnancy imposes cryopreservation of ovarian tissue for fertility preservation as a valid method and illustrates that personal life circumstances may rapidly change.
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Fertility and Sterility, 2012
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The Histochemical journal, 1997
The autometallographic technique was used to demonstrate the localization of mercury in dorsal ro... more The autometallographic technique was used to demonstrate the localization of mercury in dorsal root ganglia of adult Wistar rats. The animals were either exposed to mercury vapour, 100 micrograms Hg m-3, 6 h day-1, 5 days per week, or treated with organic mercury in the drinking water, 20 mg CH3HgCl per litre, for 4 weeks. The effect of orally administered sodium selenite on the pattern of intracellular distribution of mercury in these two situations was investigated. In rats exposed to mercury vapour alone, faint staining was present in ganglion cells. The selenite induced a conspicuous increase in the number of stained cells and in the intracellular staining intensity. In rats treated with organic mercury, mercury deposits were detected within ganglion cells and macrophages. The number of mercury-containing cells was increased by co-administration of selenite. In addition, satellite cells, the capsule and vessel walls were faintly stained. Twenty weeks after cessation of the organ...
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The Histochemical journal, 1998
A concept for the computer-assisted visualization of tubular organs is presented. Unmarked histol... more A concept for the computer-assisted visualization of tubular organs is presented. Unmarked histological zinc-stained serial sections from the epididymis of the Wistar rat were aligned to demonstrate the concept. Virtual images were made through the aligned sections and served as controls for the alignment process. Animation of the serial sections and the virtual images revealed new information about the structure of the organ under investigation. The analysis was used to upgrade the anatomical knowledge of rat epididymis by describing how the epididymal duct runs through the structure. The proximal parts of the epididymis contain large communicating septa of connective tissue dividing the caput and the upper part of the corpus epididymidis into segments. The tortuousness was high in the caput with many turns within a small area of the epididymis, whereas longer loops were found in the lower part of the corpus and cauda epididymidis. The tube of the vas deferens was found to become a...
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The Prostate, 1997
The prostate contains high amounts of free zinc ions which are excreted into the seminal fluid. T... more The prostate contains high amounts of free zinc ions which are excreted into the seminal fluid. The extra- and intracellular distribution of zinc ions using the highly specific autometallographical (AMG) method is described. Prostates from sulfide-perfused rats were excised, and the ZnS crystals were silver-enhanced to sizes detectable by the electron and light microscope. AMGZnS grains were found primarily in the acinic lumen of the lateral lobes. The dorsal lobe stained only faintly, while the ventral lobe was void of grains. At ultrastructural levels, the presence of zinc ions was confined to apical secretory vesicles and lysosome-like structure of the epithelium of mainly the lateral lobes. We suggest a constant secretion of zinc ions from the epithelial cells into both the acinar lumen and the intercellular canaliculi, and that the zinc enriched secretory cells in the prostate belong to a system of glandular cells that uses zinc ions to aggregate macromolecules to be excreted.
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Reproductive BioMedicine Online, 2014
Cryopreservation of ovarian tissue is one way of preserving fertility in young women with a malig... more Cryopreservation of ovarian tissue is one way of preserving fertility in young women with a malignant disease or other disorders that require gonadotoxic treatment. The purpose of the study was to explore how many women remained interested in continued cryostorage of their ovarian tissue beyond an initial 5-year period. Between 1999 and 2006, a total of 201 girls and young women had one ovary cryopreserved for fertility preservation in Denmark. One hundred of these met our inclusion criteria, which included a follow-up period of at least 5 years, and were mailed a questionnaire. The response rate was 95%. Sixteen of the patients (17%) stated that they wanted disposal of their tissue; the main reason was completion of family (63%). The mean age of those requesting disposal was 36.6 years, whereas those still wanting their tissue stored were significantly younger, with a mean age of 33.0 years (P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.008). In conclusion, most women with ovarian tissue cryobanked requested continued cryostorage after an initial period of at least 5 years. The main reason for requesting disposal was successful completion of a family.
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The Lancet, 2015
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Reproductive Toxicology, 1998
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Advances in Experimental Medicine and Biology, 2003
SwePub titelinformation: Epidemiologic evidence on biological and environmental male factors in e... more SwePub titelinformation: Epidemiologic evidence on biological and environmental male factors in embryonic loss.
Bookmarks Related papers MentionsView impact
Scandinavian Journal of Urology and Nephrology, 1993
The incidence of asymptomatic varicocele among 542 unselected military conscripts in Denmark was ... more The incidence of asymptomatic varicocele among 542 unselected military conscripts in Denmark was 9%. Semen from 39 of the 49 men with varicocele was compared with findings in age-matched, varicocele-free controls. The overall quality of the semen was reduced in the varicocele group (p < 0.001), with significantly lower parameters of sperm concentration, total sperm count, qualitative motility and sperm motility after 24 hours. There was also significant difference in morphology, with more amorphous spermatozoa and more with tail defects (p < 0.05) in the varicocele group. The study indicated an association between asymptomatic varicocele and compromised sperm quality. The advisability of surgical treatment was not clarified, but the two groups of men will be further observed with special regard to this question.
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Reproductive Toxicology, 1998
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Reproductive Toxicology, 1998
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Reproductive Toxicology, 2002
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Reproductive Toxicology, 2002
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Reproductive Toxicology, 1998
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Reproductive BioMedicine Online, 2011
This paper presents the Danish 10-year experience (1999-2009) with cryopreservation (n=386) and a... more This paper presents the Danish 10-year experience (1999-2009) with cryopreservation (n=386) and autotransplantation of ovarian tissue (n=18). Before applying the technique to humans, the method was thoroughly tested and validated. The cryoprotectant solution was chosen after histological evaluation of mouse and human ovarian tissue after freezing with four different combinations of cryoprotectants. Viability was confirmed by transplantation of frozen-thawed human ovarian tissue (n=49) to oophorectomized Nude mice. Viability after transport of fresh tissue 4-5h prior to freezing had previously been validated. Overnight transport of fresh ovarian tissue prior to cryopreservation was evaluated when human ovarian tissue was kept on ice for 20h and then cryopreserved. The thawed ovarian tissue was transplanted to an oophorectomized Nude mouse and histology confirmed viability. In Denmark 12 women have received a total of 18 autotransplantations of ovarian tissue. All women resumed ovarian function and three healthy babies were born to two women. In both women, the tissue was transported on ice for 4-5h prior to cryopreservation. Ovarian tissue cryopreservation is an important method for fertility preservation; however, before applying the method clinically, each laboratory should perform thorough validation of their technique.
Bookmarks Related papers MentionsView impact
PEDIATRICS, 2006
Our aim was to assess the incidence of cerebral palsy among children conceived with in vitro fert... more Our aim was to assess the incidence of cerebral palsy among children conceived with in vitro fertilization and children conceived without in vitro fertilization. A population-based, cohort study, including all live-born singletons and twins born in Denmark between January 1, 1995, and December 31, 2000, was performed. Children conceived with in vitro fertilization (9255 children) were identified through the In Vitro Fertilization Register; children conceived without in vitro fertilization (394,713) were identified through the Danish Medical Birth Register. Cerebral palsy diagnoses were obtained from the National Register of Hospital Discharges. The main outcome measure was the incidence of cerebral palsy in the in vitro fertilization and non-in vitro fertilization groups. Children born after in vitro fertilization had an increased risk of cerebral palsy; these results were largely unchanged after adjustment for maternal age, gender, parity, small-for-gestational age status, and educational level. The independent effect of in vitro fertilization vanished after additional adjustment for multiplicity or preterm delivery. When both multiplicity and preterm delivery were included in the multivariate models, preterm delivery remained associated strongly with the risk of cerebral palsy. The large proportions of preterm deliveries with in vitro fertilization, primarily for twins but also for singletons, pose an increased risk of cerebral palsy.
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Obstetrical & Gynecological Survey, 2009
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