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Hermann M. Behre

Bio: Hermann M. Behre is an academic researcher from University of Münster. The author has contributed to research in topics: Male infertility & Sperm. The author has an hindex of 29, co-authored 54 publications receiving 6705 citations. Previous affiliations of Hermann M. Behre include Martin Luther University of Halle-Wittenberg.


Papers
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Journal ArticleDOI
TL;DR: The presence of not one but three spermatogenesis loci in Yq11 is proposed and that each locus is active during a different phase of male germ cell development.
Abstract: In a large collaborative screening project, 370 men with idiopathic azoospermia or severe oligozoospermia wereanalysed for deletions of 76 DNA loci in Yq11. In 12 individuals, we observed de novo microdeletions involvingseveral DNA loci, while an additional patient had an inherited deletion. They were mapped to three differentsubregions in Yq11. One subregion coincides to the AZF region defined recently in distal Yq11. The second andthird subregion were mapped proximal to it, in proximal and middle Yq11, respectively. The different deletionsobserved were not overlapping but the extension of the deleted Y DNA in each subregion was similar in eachpatient analysed. In testis tissue sections, disruption of spermatogenesis was shown to be at the same phasewhen the microdeletion occurred in the same Yq11 subregion but at a different phase when the microdeletionoccurred in a different Yq11 subregion. Therefore, we propose the presence of not one but three spermatogenesisloci in Yq11 and that each locus is active during a different phase of male germ cell development. As the mostsevere phenotype after deletion of each locus is azoospermia, we designated them as: AZFa, AZFb and AZFc.Their probable phase of function in human spermatogenesis and candidate genes involved will be discussed. INTRODUCTIONGenes for male germ cell development are present on the Ychromosome in different species groups (1–3). In men, theposition of a spermatogenesis locus was mapped in theeuchromatic part of the long Y arm (Yq11). It was called‘azoospermia factor’ (AZF), as the first six men observed withterminal deletions in Yq were azoospermic (4). Mature spermcells were not detectable in their seminal fluid. In all cases, the Ydeletions included the large heterochromatin block of the long Yarm (Yq12) and an undefined amount of the adjacent euchromatin(Yq11). Subsequently, the presence of AZF in Yq11 wasconfirmed by numerous studies at both cytogenetic (5) andmolecular level (6–8). However, the genetic complexity of AZFcould not be revealed by these analyses.This first became possible by the detection of sterile patientswith small interstitial deletions (i.e. microdeletions) in Yq11. Ina study with 13 sterile men suffering from idiopathic azoospermiatwo different microdeletions in Yq11 were observed (9). Theywere mapped to two non overlapping positions in Yq11 interval6 (10). However, further studies of Yq11 microdeletionsassociated to the phenotype of male sterility, only confirmed theposition of an AZF locus in distal Yq11 (11,12). The mostextensive study was performed by Reijo et al. (13) on 89 sterile

1,246 citations

Journal ArticleDOI
TL;DR: In this paper, the effects of androgen treatment of hypogonadal men on multiple target organs and the recent studies show short-term beneficial effects of testosterone in older men that are similar to those in younger men.
Abstract: Demographic data clearly demonstrate that the percentage of the population in the older age group is increasing. Androgen deficiency in the aging male has become a topic of increasing interest and debate throughout the world. Cross-sectional and longitudinal data indicate that the testosterone falls progressively with age and that a significant percentage of men over the age of 60 years have serum testosterone levels that are below the lower limits of young adult (age 20–30 years) men (1–4). The principal questions raised by these observations are whether older hypogonadal men will benefit from testosterone treatment and what will be the risks associated with such intervention. The past decade has brought evidence of benefit of androgen treatment of hypogonadal men on multiple target organs and the recent studies show short-term beneficial effects of testosterone in older men that are similar to those in younger men. This has been comprehensively reviewed and summarized by the Institute of Medicine in ‘Testosterone and Aging: Clinical Research Directions’ (5). Long-term data on the effects of testosterone treatment in the older population are limited mainly to effects on body composition and bone mass (6–11). Key questions of the effects of testosterone on patient reported outcomes and functional benefits that may retard physical or mental frailty of the elderly or improve the quality of life are not yet available. Specific risk data on the prostate and cardiovascular systems are needed.

968 citations

Journal ArticleDOI
TL;DR: In hypogonadal men, BMD can be normalized and maintained in the normal range by continuous, long term testosterone substitution, and is seen during the first year of treatment in previously untreated patients with low initial BMD.
Abstract: In both men and women, a decrease in bone mineral density (BMD) is a major symptom of hypogonadism. Although the effects of estrogens on osteoporosis in women are well documented, comparatively little is known about the effects of long term testosterone substitution on BMD in hypogonadal men. Therefore, we studied BMD in 72 hypogonadal patients (37 men with primary and 35 men with secondary hypogonadism) under testosterone substitution therapy that continued for up to 16 yr. Thirty-two of these men were also seen before initiation of therapy. At annual intervals, trabecular BMD of the lumbar spine was measured by quantitative computed tomography, a true volumetric and reproducible method for long term serial BMD measurements. Serum levels of testosterone increased to the normal range in all androgen-treated hypogonadal men. The most significant increase in BMD was seen during the first year of testosterone treatment in previously untreated patients, when BMD increased from 95.2 +/- 5.9 to 120.0 +/- 6.1 mg/cm3 hydroxyapatite (mean +/- SE). Long term testosterone treatment maintained BMD in the age-dependent reference range in all 72 hypogonadal men, independent of the type of hypogonadism. Transdermal testosterone patches applied to the scrotum were as effective in normalizing BMD as im testosterone enanthate injections. In summary, testosterone therapy increases BMD in hypogonadal men regardless of age. The greatest increase is seen during the first year of treatment in previously untreated patients with low initial BMD. In hypogonadal men, BMD can be normalized and maintained in the normal range by continuous, long term testosterone substitution.

523 citations

Journal ArticleDOI
TL;DR: This research presents a meta-analysis of 129 cases of meningitis in mice over a 12-month period and shows clear trends in progeria and in particular in cases of high prolapse preoperatively and during the course of pregnancy.
Abstract: Demographic data clearly demonstrate that the percentage of the population in the older age group is increasing. Androgen deficiency in the aging male has become a topic of increasing interest and debate throughout the world. Cross-sectional and longitudinal data indicate that the testosterone falls progressively with age and that a significant percentage of men over the age of 60 years have serum testosterone levels that are below the lower limits of young adult (age 20–30 years) men (1–4). The principal questions raised by these observations are whether older hypogonadal men will benefit from testosterone treatment and what will be the risks associated with such intervention. The past decade has brought evidence of benefit of androgen treatment of hypogonadal men on multiple target organs and the recent studies show short-term beneficial effects of testosterone in older men that are similar to those in younger men. This has been comprehensively reviewed and summarized by the Institute of Medicine in ‘Testosterone and Aging: Clinical Research Directions’ (5). Long-term data on the effects of testosterone treatment in the older population are limited mainly to effects on body composition and bone mass (6–11). Key questions of the effects of testosterone on patient reported outcomes and functional benefits that may retard physical or mental frailty of the elderly or improve the quality of life are not yet available. Specific risk data on the prostate and cardiovascular systems are needed.

473 citations

01 Jan 2001
TL;DR: Scope and Goals * Biology of Reproduction, Physiologym * Sperm Maturation and Fertilization * Classification of Andrological Disorders * Diagnosis of Male Infertility and Hypogonadism * Diseases of the Hypothalamus and Pituitary Gland * Disorders at the Testicular Level
Abstract: Scope and Goals * Biology of Reproduction,- Physiologym * Sperm Maturation and Fertilization * Classification of Andrological Disorders * Diagnosis of Male Infertility and Hypogonadism * Diseases of the Hypothalamus and Pituitary Gland * Disorders at the Testicular Level * Diseases of the Seminal Ducts * Disorders of Sperm Deposition * Disorders of the Androgen Target Organs * Testicular Dysfunction in Systemic Diseases * Occupational and Environmental Influences on Male Fertility * Gynecology Relevant to Andrology * Testosterone Therapy * Empirical Therapies for Idiopathic Male Infertility * Assisted Fertilization * Cryopreservation of Sperm * The Psychology of Fertility Disorders in Males * Male Contribution to Contraception * Senescence * Ethical Aspects of Reproductive Medicine.

427 citations


Cited by
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Journal ArticleDOI
TL;DR: Existing evidence supporting a new concept that poor semen quality, testis cancer, undescended testis and hypospadias are symptoms of one underlying entity, the testicular dysgenesis syndrome (TDS), which may be increasingly common due to adverse environmental influences is summarized.
Abstract: Numerous reports have recently focused on various aspects of adverse trends in male reproductive health, such as the rising incidence of testicular cancer; low and probably declining semen quality; high and possibly increasing frequencies of undescended testis and hypospadias; and an apparently growing demand for assisted reproduction. Due to specialization in medicine and different ages at presentation of symptoms, reproductive problems used to be analysed separately by various professional groups, e.g. paediatric endocrinologists, urologists, andrologists and oncologists. This article summarizes existing evidence supporting a new concept that poor semen quality, testis cancer, undescended testis and hypospadias are symptoms of one underlying entity, the testicular dysgenesis syndrome (TDS), which may be increasingly common due to adverse environmental influences. Experimental and epidemiological studies suggest that TDS is a result of disruption of embryonal programming and gonadal development during fetal life. Therefore, we recommend that future epidemiological studies on trends in male reproductive health should not focus on one symptom only, but be more comprehensive and take all aspects of TDS into account. Otherwise, important biological information may be lost.

2,096 citations

Journal ArticleDOI
TL;DR: The guidelines for the evaluation and treatment of androgen deficiency syndromes in adult men published previously in 2006 were updated by the Task Force of the Clinical Guidelines Subcommittee of The Endocrine Society.
Abstract: Objective: Our objective was to update the guidelines for the evaluation and treatment of androgen deficiency syndromes in adult men published previously in 2006. Participants: The Task Force was composed of a chair, selected by the Clinical Guidelines Subcommittee of The Endocrine Society, five additional experts, a methodologist, and a medical writer. The Task Force received no corporate funding or remuneration. Conclusions: We recommend making a diagnosis of androgen deficiency only in men with consistent symptoms and signs and unequivocally low serum testosterone levels. We suggest the measurement of morning total testosterone level by a reliable assay as the initial diagnostic test. We recommend confirmation of the diagnosis by repeating the measurement of morning total testosterone and, in some men in whom total testosterone is near the lower limit of normal or in whom SHBG abnormality is suspected by measurement of free or bioavailable testosterone level, using validated assays. We recommend testos...

1,900 citations

Journal ArticleDOI
TL;DR: Fertility preservation is often possible in people undergoing treatment for cancer and should be considered as early as possible during treatment planning, to preserve the full range of options.
Abstract: Purpose To develop guidance to practicing oncologists about available fertility preservation methods and related issues in people treated for cancer. Methods An expert panel and a writing committee were formed. The questions to be addressed by the guideline were determined, and a systematic review of the literature from 1987 to 2005 was performed, and included a search of online databases and consultation with content experts. Results The literature review found many cohort studies, case series, and case reports, but relatively few randomized or definitive trials examining the success and impact of fertility preservation methods in people with cancer. Fertility preservation methods are used infrequently in people with cancer. Recommendations As part of education and informed consent before cancer therapy, oncologists should address the possibility of infertility with patients treated during their reproductive years and be prepared to discuss possible fertility preservation options or refer appropriate and interested patients to reproductive specialists. Clinician judgment should be employed in the timing of raising this issue, but discussion at the earliest possible opportunity is encouraged. Sperm and embryo cryopreservation are considered standard practice and are widely available; other available fertility preservation methods should be considered investigational and be performed in centers with the necessary expertise.

1,784 citations

Journal ArticleDOI
TL;DR: Symptoms of poor morning erection, low sexual desire, erectile dysfunction, inability to perform vigorous activity, depression, and fatigue were significantly related to the testosterone level, and an inverse relationship between an increasing number of sexual symptoms and a decreasing testosterone level was observed.
Abstract: BACKGROUND The association between aging-related testosterone deficiency and late-onset hypogonadism in men remains a controversial concept. We sought evidence-based criteria for identifying late-onset hypogonadism in the general population on the basis of an association between symptoms and a low testosterone level. METHODS We surveyed a random population sample of 3369 men between the ages of 40 and 79 years at eight European centers. Using questionnaires, we collected data with regard to the subjects' general, sexual, physical, and psychological health. Levels of total testosterone were measured in morning blood samples by mass spectrometry, and free testosterone levels were calculated with the use of Vermeulen's formula. Data were randomly split into separate training and validation sets for confirmatory analyses. RESULTS In the training set, symptoms of poor morning erection, low sexual desire, erectile dysfunction, inability to perform vigorous activity, depression, and fatigue were significantly related to the testosterone level. Increased probabilities of the three sexual symptoms and limited physical vigor were discernible with decreased testosterone levels (ranges, 8.0 to 13.0 nmol per liter [2.3 to 3.7 ng per milliliter] for total testosterone and 160 to 280 pmol per liter [46 to 81 pg per milliliter] for free testosterone). However, only the three sexual symptoms had a syndromic association with decreased testosterone levels. An inverse relationship between an increasing number of sexual symptoms and a decreasing testosterone level was observed. These relationships were independently confirmed in the validation set, in which the strengths of the association between symptoms and low testosterone levels determined the minimum criteria necessary to identify late-onset hypogonadism. CONCLUSIONS Late-onset hypogonadism can be defined by the presence of at least three sexual symptoms associated with a total testosterone level of less than 11 nmol per liter (3.2 ng per milliliter) and a free testosterone level of less than 220 pmol per liter (64 pg per milliliter).

1,211 citations