Enriching the captive elephant population genetic pool through artificial insemination with frozen-thawed semen collected in the wild

The first successful AI in an elephant was reported in 1998, using fresh semen. Since then almost 40 calves have been produced through AI in both Asian and African elephants worldwide. Following these successes, with the objective of enriching the captive population with genetic material from the wild, we evaluated the possibility of using frozen-thawed semen collected from wild bulls for AI in captivity. Semen, collected from a 36-yr-old wild African savanna elephant (Loxodonta africana) in South Africa was frozen using the directional freezing technique. This frozen-thawed semen was used for four inseminations over two consecutive days, two before and two after ovulation, in a 26-yr-old female African savanna elephant in Austria. Insemination dose of 1200 × 10(6) cells per AI with 61% motility resulted in pregnancy, which was confirmed through ultrasound examination 75, 110 and 141 days after the AI procedure. This represents the first successful AI using wild bull frozen-thawed semen in elephants. The incorporation of AI with frozen-thawed semen into the assisted reproduction toolbox opens the way to preserve and transport semen between distant individuals in captivity or, as was done in this study, between wild and captive populations, without the need to transport stressed or potentially disease-carrying animals or to remove animals from the wild. In addition, cryopreserved spermatozoa, in combination with AI, are useful methods to extend the reproductive lifespan of individuals beyond their biological lifespan and an important tool for genetic diversity management and phenotype selection in these endangered mammals.

Estrus induction in white rhinoceros (Ceratotherium simum)

The estrous cycle length in the white rhinoceros (Ceratotherium simum) is either 4 or 10 wk. The cause(s) for this variation as well as the poor fertility rate in captivity remains under debate in this species. Most captive adult white rhinoceros undergo long anovulatory periods without luteal activity which are considered a major reason for their low reproductive rate. In this study, the synthetic progestin chlormadinone acetate (CMA) was tested in combination with hCG or the GnRH analogue deslorelin for its efficiency to induce ovulation in fourteen females without luteal activity and in three, regular cycling females. HCG (N = 12), injectable GnRH analogue (N = 8) and GnRH analogue implants (N = 15) were given to induce ovulation after CMA treatment. Treatment success was determined using both transrectal ultrasonography and progesterone metabolite EIA analysis. A preovulatory sized follicle (3.5 ± 0.1 cm) or a corpus luteum (5.1 ± 0.7) was present on the ovary one day after induction in 93.1% of the treatments. Despite this high rate of ovarian response, ovulation rate differed between the study groups. The ovulation rate for hCG, injectable GnRH analogue and GnRH analogue implants was 66.7%, 62.5% and 93.3%, respectively. Ovulation rate in cyclic females treated with GnRH implants was 100% (6/6) compared with 89% (8/9) in females without luteal activity receiving the same treatment. The length of the estrous cycle when induced with hCG was 4 wk (85.7%). The estrous cycle when induced with GnRH analogue was predominantly 10 wk long. Two females without luteal activity treated with GnRH became pregnant. In conclusion, CMA in combination with GnRH analogue implants was highly effective to induce ovulation in white rhinoceroses and thus can contribute to efforts aimed at increasing natural mating and reproductive rates in the captive white rhinoceros population.

Dystocia and fetotomy associated with cerebral aplasia in a greater one-horned rhinoceros (Rhinoceros unicornis)

The captive greater one-horned rhinoceros population consists of 176 animals. Since 1971, a total of 226 calves were born into this captive population. However, 24% of the offspring born were either stillborn or did not survive the first 3 months. The causes for this high rate of stillbirth and neonate mortality have not yet been documented. Here, we report on the veterinary management of a dystocia and foetotomy resulting from a malpositioned greater one-horned rhinoceros foetus. The dead foetus presented with a forelimb flexed at the shoulder joint, with all other joints extended. The foetus was dissected into five parts and extracted during two anaesthesias on two consecutive days. The dam recovered fully and came into oestrous 31 days after surgery. Post-mortem and CT examination of the malformed foetal head revealed cranioschisis with cerebral aplasia and cerebellar hypoplasia. The cerebral aplasia presented here and in other recent cases suggests that neural tube defects and cranial malformations may be associated with more captive rhinoceros stillbirths than previously considered. Epidemiologic studies of these phenomena and possible nutritional deficiencies or hereditary defects are warranted.

Cooling and freezing of epididymal sperm in the common hippopotamus (Hippopotamus amphibius)

Knowledge concerning reproduction in common hippopotamus is scarce and in particular very little is known about male reproductive physiology and sperm cryopreservation. Testes were obtained from nine castrated bulls and sperm extracted from the epididymides of eight of these individuals. Mean ± SEM values of reproductive parameters were: testicular weight (including epididymis and tunicas)--275.9 ± 54.1 g, total sperm motility--88.1 ± 4.2%, total cells extracted--11.0 ± 3.6 × 10(9), intact acrosome--87.7 ± 1.8%, intact sperm morphology--51.6 ± 4.1%, and, for 3 individuals, hypoosmotic swelling test for membrane integrity-83.3 ± 1.8%. Chilled storage extenders tested were Berliner Cryomedium (BC), Biladyl(®), modification of Kenney modified Tyrode's medium (KMT), and Human Sperm Refrigeration Medium (HSRM). Extender had significant effect on post-dilution motility and motility and intact morphology after 4h and 24h at 4°C (P ≤ 0.007 for all). Berliner Cryomedium and HSRM were superior to Biladyl(®) and KMT. Freezing extenders tested were BC with either 6% dimethyl sulfoxide (Me(2)SO), or 5%, 7%, or 10% glycerol. Post-thaw motility was < 5% in 3/7 bulls in all extenders. When frozen in BC with 6% Me(2)SO, one bull had 15% post-thaw motility and 3/7 had 20 to 60%. In glycerol, 3/7 had 15-30% post-thaw motility in 5%, 2/7 in 7%, and 1/7 in 10%. The extender had significant effect on post-chilling motility (P = 0.008), post-thaw morphology (P = 0.016), and motility 30 min after thawing (P = 0.015). Berliner Cryomedium with 6% Me(2)SO or 7% glycerol were the freezing extenders of choice. Information obtained in this study allows initiation of cryobanking of sperm from the common hippopotamus which is of particular importance for genetically valuable individuals.

Seminoma in a southern black rhinoceros (Diceros bicornis minor): diagnosis, surgical management and effect on fertility

A testicular mass was identified by ultrasonography performed during a routine reproductive evaluation of an adult male southern black rhinoceros (Diceros bicornis minor). Histological examination of a testicular biopsy supported a presumptive diagnosis of testicular neoplasia. Hemi-castration was performed to excise the affected testis and a pathological diagnosis of a seminoma was made. Assessment of semen suggested reduced fertility as a consequence of the neoplastic process, but hemi-castration prevented further growth and metastasis of the tumour and ensured the animal's breeding potential. This is the second documented case of a seminoma in a rhinoceros species and the first case in a black rhinoceros.

Ovarian superstimulation, transrectal ultrasound-guided oocyte recovery, and IVF in rhinoceros

Numerous reports on reproductive pathology in all rhinoceros species illustrate the abundance of female infertility in captive populations. In infertile rhinoceroses, oocyte collection and embryo production could represent the best remaining option for these animals to reproduce and to contribute to the genetic pool. We report here on superstimulation, repeated oocyte recovery, and attempted in vitro fertilization (IVF) in white and black rhinoceroses. Four anestrous rhinoceroses (two white, two black) with unknown follicular status were treated with gonadotropin-releasing hormone analogue, deslorelin acetate, for 6 to 7 d. Number and size of follicles in superstimulated females was significantly higher and larger compared with those in nonstimulated anestrous females (n=9). Ovum pick-up was achieved by transrectal ultrasound-guided follicle aspiration. Up to 15 follicles were aspirated per ovary. During six ovum pick-ups, a total of 29 cumulus-oocyte complexes (COCs) were harvested with a range of 2 to 9 COCs per collection. No postsurgical complications were noted on the rhinoceros ovaries using this minimally invasive approach. Various in vitro maturation (IVM) and IVF protocols were tested on the collected COCs. Despite the low total number of COCs available for IVM and IVF in this study, we can report the first rhinoceros embryo ever produced in vitro. The production of a 4-cell embryo demonstrated the potential of transrectal ultrasound-guided oocyte recovery as a valuable tool for in vitro production of rhinoceros embryos from otherwise infertile females.

Frozen-thawed rhinoceros sperm exhibit DNA damage shortly after thawing when assessed by the sperm chromatin dispersion assay

This study reports on the successful validation (via in situ nick translation and neutral comet assay) of the equine Sperm-Halomax kit as an appropriate methodology for the assessment of sperm DNA fragmentation in three species of rhinoceros. Rhinoceros sperm nuclei with fragmented DNA (validated using in situ nick translation) were evident as large halos with dispersed DNA fragments, whereas those with nonfragmented DNA displayed small halos of nondispersed DNA within the microgel. There was a high correlation (r) of 0.974 (R(2) value=0.949; P<0.01; n=16) between the respective assessments of the Sperm Chromatin Dispersion test (SCDt) and the neutral comet assay. Application of the SCDt to determine the DNA fragmentation dynamics of rhinoceros (n=6) sperm frozen in liquid nitrogen vapor and incubated postthaw at 37 degrees C for up to 48 h to mimic in vitro conditions in the female reproductive tract, revealed an increase (P=0.001) in DNA damage, as soon as 4h after the start of incubation. Linear regression equations were calculated for all six rhinoceroses over the first 6h of incubation and revealed individual animal variation. Freshly collected and incubated (37 degrees C) rhinoceros (n=3) sperm had no increase in the basal level of DNA fragmentation for up to 48 h, indicating that the cryopreservation of rhinoceros sperm in liquid nitrogen vapor, as used in this study, appeared to result in freeze-thaw DNA damage.

Assisted Reproduction in Female Rhinoceros and Elephants ? Current Status and Future Perspective

Over the last few decades, rhinoceroses and elephants became important icons in the saga of wildlife conservation. Recent surveys estimate the wild Asian (Elephas maximus) and African (Loxodonta africana) elephant populations to be, at most, 50 250 and 637 600 respectively. For the five rhinoceros species, black (Diceros bicornis), white (Ceratotherium simum), Indian (Rhinoceros unicornis), Javan (Rhinoceros sondaicus) and Sumatran rhinoceros (Dicerorhinus Sumatrensis), the population estimates of 3610, 11 330, 2400, 60 and 300, respectively, are of even greater concern. Protected against habitat loss, poaching and left undisturbed, rhinoceros and elephants reproduce well in the wild. But small and decreasing populations make successful captive management of these taxa increasingly important. In captivity, however, most populations face possible 'extinction' because of historically poor reproductive performance. From the first descriptions of the reproductive anatomy and the oestrous cycle (Laws 1969; Kassam and Lasley 1981; Balke et al. 1988a,b; Plotka et al. 1988; Godfrey et al. 1991) to the present use of advanced assisted reproduction technologies, researchers have strive to understand the function and dysfunction of the reproductive biology of these charismatic species. This paper reviewed the current knowledge on rhinoceros and elephant reproduction biology, reproductive cycle, gestation, dystocia, reproductive pathology, oestrous induction and artificial insemination, sperm sexing, IVF and contraception, and how this knowledge is or might be used to aid species conservation for maximal reproductive efficiency and enhancement of genetic management.

Artificial insemination in the anoestrous and the postpartum white rhinoceros using GnRH analogue to induce ovulation

The objective of this study was to develop AI and to achieve first time pregnancy in a nulliparous rhinoceros. For this, one 24-year-old irregular cycling female white rhinoceros was selected, which had never been mated. The endocrine function was monitored by faecal and serum pregnane analysis. Ultrasound determined the optimal day for AI by measuring follicle sizes of 2.0, 2.6, 3.0, 3.2 cm on days -6, -4, -1, 0 of the induced oestrous cycle, respectively. AI was performed and ovulation induced when a pre-ovulatory-sized follicle was present using GnRH analogue, deslorelin. Fresh semen was deposited in the uterine horn using a patented AI catheter overcoming the hymeneal membrane and torturous cervical folds non-surgically. Moreover, ultrasound monitoring of the uterine involution and ovarian activity on days 16, 26, 30 postpartum facilitated the induction of and the AI on the first postpartum oestrous in a rhinoceros using GnRH analogue. Two consecutive pregnancies were achieved by AI for the first time in the rhinoceros. Pregnancies were diagnosed by elevated serum and faecal 20-oxo-pregnane concentrations. In addition ultrasound measured biometric parameters of the two foetuses on days 86 and 133 of gestation. Two female calves were born after 490 and 502 days of gestation, yet one calf was stillborn. AI in rhinoceros might now be used as assisted reproduction technology tool to boost critically small captive rhinoceros populations.

Ultrasonographic assessment and ultrasound-guided biopsy of the retropharyngeal lymph nodes in Asian elephants (Elephas maximus)

Endotheliotropic herpesvirus causes a fatal disease in young Asian elephants, but there are no methods for identifying latent carriers of the virus. During the postmortem study of one female African elephant and three male and two female Asian elephants, a lymph node located bilaterally caudoventral to the parotid gland, approximately 1.5 to 5 cm below the skin, was identified as suitable for transcutaneous ultrasound-guided biopsy. An ultrasonographic assessment and two biopsies were performed on 39 Asian elephants, and these lymph nodes were classified ultrasonographically as active, inactive or chronically active. The calculated mean (se) volume of 10 active lymph nodes was 17.4 (6.9) cm(3), and that of three chronically active lymph nodes was 10.6 (1.0) cm(3), whereas the mean volume of 17 inactive lymph nodes was 3.1 (0.6) cm(3). The presence of lymph node tissue in samples obtained by ultrasound-guided biopsy from three animals that were maintained under conditions that allowed for additional sampling was confirmed histologically. The dna extracted from the lymphoid tissue and the whole blood of all the elephants was negative for endotheliotropic herpesvirus by PCR.

Reproductive problems directly attributable to long-term captivity–asymmetric reproductive aging

Problems attributable to long-term captivity have been identified and are responsible for the difficulties in establishing successful reproduction in captive populations of wildlife, specifically, elephants and rhinoceroses. Historically, non-reproductive periods of 10-15 years in nulliparous female rhinoceroses and elephants have not been considered problematic. New evidence suggests that prolonged exposure to endogenous sex steroids and that long stretches of non-reproductive periods induce asymmetric reproductive aging in captive animals. The consequences are reduced fertility, shortened reproductive life-span and, eventually, irreversible acyclicity. Although age-related reproductive lesions have also been documented in male rhinoceroses, they continue to maintain a longer reproductive life-span than females. Since human and domestic animal models have already indicated that early pregnancy provides natural protective mechanism against asymmetric reproductive aging processes and premature senescence, it is imperative that appropriate counter measures such as assisted reproductive technologies (ART) be utilized to ensure early pregnancy in captive animals for their preservation and to ensure increased genetic diversity of the captive populations.

Serum levels of dimeric and monomeric inhibins and the degree of seminal alteration in infertile men with varicocele

The aim of the present study was to establish the serum levels of inhibins and their relationship with the degree of seminal alteration in infertile men. Thirty-six patients with varicocele (Va) and seven non-obstructive azoospermic men (Az) were included. The Va group was divided into two subgroups: Va I (sperm concentration: >20 x 106; n = 21) and Va II (sperm concentration: < 20 x 106; n = 15). Twelve fertile men were included as a control group (Co). Semen analysis and serum follicle stimulating hormone (FSH), luteinizing hormone (LH), testosterone (T), inhibin B and Pro-alphaC levels were determined. Serum inhibin B and T levels were significantly lower and FSH and LH significantly higher in group Az when compared with the Co. Inhibin B was unable to differentiate Va I from Va II groups. However, in Va II an increase in FSH levels was observed. An inverse correlation between inhibin B and FSH, a direct correlation between inhibin B and testosterone, sperm concentration, motility and morphology were found. No such correlations were seen when only the Va group was analysed. The lack of correlation between serum levels of inhibin B, gonadotrophins, sperm concentration and seminal parameters observed in Va, adds other factor to the complex pathophysiology of varicocele. Finally, further studies are needed to elucidate if oligozoospermic patients with varicocele have also an impaired negative feed-back mechanism that regulates FSH synthesis and secretion.

Establishment of assisted reproduction technologies in female and male African wild dogs (Lycaon pictus)

Transrectal ultrasonography, electroejaculation and cryopreservation of spermatozoa were applied to the African wild dog (Lycaon pictus) to establish non-invasive protocols for assessing the reproductive health of one of the most endangered African canids. Transrectal ultrasonography was performed on immobilized male (n = 2) and female (n = 5) captive wild dogs. The testes and epididymides of the male dogs were imaged transcutaneously, followed by electrostimulation and cryopreservation of spermatozoa. The sonomorphology of the female and male urogenital tracts was characterized. In females, the vagina, cervix, non-pregnant uterus and ovary were imaged and the reproductive health of each female was evaluated. The sonographic assessment helped to identify one pyometra and extensive abdominal fat deposits in two other individuals in which pyometra had been suspected. Images of the adrenal glands showed differences in size among individuals of the same breeding group. Whether these differences were related to the dominance hierarchy remains to be determined. In males, visualization of the prostate gland, testis and epididymis indicated sexual maturity. Three ejaculatory fractions (1.0, 1.5 and 0.5 ml, with 50, 95 and 95% motility, respectively; 1.125 x 10(8) spermatozoa per ejaculate) were collected from one male. The motility of each of these fractions after thawing was 0, 30 and 40%, respectively. Electrostimulation of the second male, in which a cystic structure in a testis had been identified by sonography, resulted in an aspermic ejaculate (0.5 and 1.0 ml). These technologies provided basic data on reproduction in female and male African wild dogs and were an efficient way to evaluate reproductive health.

Demonstration of 2-unsaturated C19-steroids in the urine of female Asian elephants, Elephas maximus, and their dependence on ovarian activity

Air-borne volatile substances have been demonstrated to signal oestrus, induce ovulation and synchronize ovarian activity in different mammals. An oestrous-related pheromone of the female Asian elephant (Elephas maximus) is known to induce behavioural responses in elephant bulls. Additional data revealed that timing of oestrus in females with close social relationships tends to be synchronized. Therefore, urine from female Asian elephants might be expected to contain luteal phase-dependent volatile substances, which may function as additional chemical signals in this species. The aim of the present study was to identify such compounds and to investigate their pattern of excretion throughout the ovarian cycle. Urine samples were collected three times a week during the follicular phase and one to three times a week during the luteal phase from five adult female Asian elephants from a total of 13 non-conception cycles and one conception cycle, including the first 72 weeks of pregnancy. A simple headspace solid-phase microextraction method has been developed for quantification of urinary volatile substances and analysis was performed by gas chromatography. The comparison of urine collected during the follicular and the luteal phase indicated the presence of two luteal phase-dependent substances. Mass spectrometry was used to identify one substance as 5alpha-androst-2-en-17-one and a second substance as the corresponding alcoholic compound 5alpha-androst-2-en-17beta-ol. The 5alpha-androst-2-en-17beta-ol and -17-one profiles reflected cyclic ovarian activity with clear (10-20-fold) luteal phase increases. Furthermore, measurements of both compounds were correlated positively with the concentration of urinary pregnanetriol and indicated cycle duration (15.1 +/- 1.2 weeks) similar to that obtained from pregnanetriol measurements (15.2 +/- 1.6 weeks). The results demonstrate the presence of two luteal phase-specific steroidal volatile compounds in elephant urine. One of the substances, 5alpha-androst-2-en-17-one, has been demonstrated in human axillary bacterial isolates. The measurement of both volatile substances in elephant urine can be used for rapid detection of the stage of the ovarian cycle, as the analysis can be completed within 2 h.

Ultrasonography as an important tool for the development and application of reproductive technologies in non-domestic species

Ultrasound imaging in reproductive sciences offers new opportunities regarding optimization of the induction of the sexual cycle and ovulation, superovulation regimes, contraception programs, semen collection and testicular sperm extraction techniques, ovum pick up and ovarian transplantation procedures, as well as the application of artificial insemination, embryo collection and transfer. In non-domestic species, most of which lack basic data, ultrasonography is an ideal tool to study reproductive biology in both captive and wild populations. The use of this imaging modality led us to develop new, or modify established, reproductive technologies. Ultrasonography has been an integral part of over 200 assisted reproduction procedures in 17 mammalian species performed by our research team between 1992 and 1999. These procedures included the initial characterization of sexual cycles, hormonal cycle induction, semen collection by electroejaculation or manual stimulation, non-surgical artificial insemination (AI), non-surgical embryo transfer and temporary hormonal contraception. For these investigations, a variety of newly developed equipment was applied and species-specific hormonal treatments designed. We used several commercial and customized ultrasound systems with a variety of technical features. Some relevant improvements of these applications will be described and the role of ultrasonography elucidated to.

Hypothalamic-pituitary-testicular axis and seminal parameters in hyperthyroid males

Information on the effect of abnormal thyroid function on male reproduction is less available than that for the female. To assess the effects of hyperthyroidism on hypothalamic-pituitary-testicular axis and on spermogram parameters, 25 male patients (19-47 years old) suffering from active Graves' disease were studied. Serum luteinizing hormone (LH), follicle stimulating hormone (FSH), and prolactin (PRL) were measured before and after administration of 100 microg GnRH plus 200 microg thyrotropin-releasing hormone (TRH). Testosterone (T), estradiol (E2), and 17-hydroxyprogesterone (17-OHP) were determined before and after 5000 IU human chorionic gonadotropin (HCG) administration. Serum sex hormone-binding globulin (SHBG), cortisol-binding globulin (CBG), androstenedione and bioavailable testosterone (bioT), and bioavailable estradiol (bioE2) were also measured. Spermograms according to World Health Organization (WHO) criteria were determined in 21 patients. Hormonal and seminal studies were repeated in six patients after 7 to 19 months of euthyroidism achieved after treatment for hyperthyroidism. As a control group, 10 normal men were evaluated. Impaired sexual function, gynecomastia, and low testicular volume were found in 12, 6, and 3 hyperthyroid patients. Mean basal LH was significantly higher than the control group (7.8 +/- 4.7 vs. 5.0 +/- 1.9 mIU/mL, respectively, p < 0.02), with hyperresponse to GnRH. The response of PRL to TRH was lower in patients versus control group (30 minutes: 3.9 +/- 3.4 and 12.0 +/- 2.8 ng/mL, p < 0.01). Basal levels of steroids and SHBG were significantly higher in patients than in normal men (T: 9.3 +/- 3.3 vs. 5.4 +/- 1.6 ng/mL, p < 0.005; E2: 62.2 +/- 25.2 vs. 32.1 +/- 11.0 pg/mL, p < 0.005; 17-OHP: 2.4 +/- 0.9 vs. 1.1 +/- 0.5 ng/mL, p < 0.001; SHBG: 102.3 +/- 37.3 vs. 19.0 +/- 5.0 nmol/L, p < 0.01). The maximal increment of T and 17-OHP after HCG was lower in hyperthyroid patients than in normal men (p < 0.019 and p < 0.001, respectively). Basal bioT was lower in patients than controls (1.7 +/- 0.8 and 3.1 +/- 1.9 ng/mL, p < 0.02). The following incidence of abnormal semen parameters was found: asthenospermia 85.7%, hypospermia 61.9%, oligospermia 42.9%, necrospermia 42.9% and teratospermia 19.0%. In euthyroidism, a normalization of 85% of seminal alterations was observed in the limited number of patients evaluated. Our results confirm that hyperthyroidism causes marked alterations of the gonadotropic and PRL axis and dramatically affects spermatic function. BioT measurement was useful to identify hypoandrogenism in these patients in spite of the high concentration of total testosterone. The restoration of most semen parameters when euthyroidism was achieved suggests that the alterations were induced by the Graves' disease.

Acephalic spermatozoa and abnormal development of the head-neck attachment: a human syndrome of genetic origin

A series of 10 young sterile men with acephalic spermatozoa or abnormal head-mid-piece attachments is presented. Nine of these patients had 75-100% spermatozoa with minute cephalic ends and 0-25% abnormal head-middle piece attachments. Loose heads ranged between 0-35 for each 100 spermatozoa and normal forms were rare. Two patients were brothers. On ultrastructural examination, the head was generally absent and the middle piece was covered by the plasma membrane. When present, heads implanted at abnormal angles on the middle piece. A testicular biopsy showed abnormal spermiogenesis. The implantation fossa was absent and the flagellar anlage developed independently from the nucleus, resulting in abnormal head-middle piece connections. In one patient azoospermia was induced with testosterone to attempt to increase the normal sperm clone during the rebound phenomenon, but all newly formed spermatozoa were acephalic. In another patient with high numbers of defective head-mid-piece connections, microinjections of spermatozoa resulted in four fertilized oocytes, but syngamy and cleavage did not take place, suggesting an abnormal function of the centrioles. The findings indicate that acephalic spermatozoa arise in the testis as the result of an abnormal neck development during spermiogenesis. The familial incidence and the typical phenotype strongly suggest a genetic origin of the syndrome.

Transrectal ultrasonographic examination of the female urogenital tract in nonpregnant and pregnant captive bears (Ursidae)

The development of reliable methods for monitoring the reproductive cycle of bears is needed to optimise breeding management in captivity. The aim of the present study was to develop non-invasive procedures for obtaining basic data on the reproductive status of nonpregnant and pregnant bears. Eight female captive bears (five Ursus arctos arctos, two Tremarctos ornatus and one Melursus ursinus) were examined using transrectal adaptor ultrasonographic imaging. Plasma concentrations of progesterone and gestagens in faeces were determined simultaneously. The ultrasonographic appearance of the female urogenital tract was assessed during the nonbreeding season and verified in four adult bears post mortem. Pregnant bears were examined twice, as the reproductive physiology of bears is characterized by delayed implantation and pseudopregnancy. During embryonic diapause there was no difference between pseudopregnant and pregnant bears both by ultrasonographic imaging and endocrinological data. After implantation (early December) the pregnancies were visualised by ultrasonographic imaging, whereas plasma concentrations of progesterone and gestagens in faeces had not yet increased. In conclusion, both transrectal ultrasonographic imaging and gestagen monitoring in faeces are efficient methods for obtaining important data on reproduction in bears.

[Preparation and characterization of amphiphilic membranes with lyotropic mesophases for simulation of skin permeation resistance]

New amphiphilic polymer networks based on methacrylates with amphiphilic side-chains were prepared by cross-linking. Undecanol was the lipophilic part and tetraoxyethylen the hydrophilic part of the side-chain. The cross-linking was performed by a similarly derived amphiphilic dimethacrylate connecting structure. To characterize the relevant membrane features, like solvatation, degree of cross-linking, phase behavior and glass transition temperature, predominantly the swelling properties in water as well as in certain organic solvents, but also polarisation microscopic examinations were used. It was intented to assess the dependence of these parameters from the degree of cross-linking. For this reason the different systems were ranked accordingly to their cross-linking. Their swelling degree was determined in the indifferent dioxane as swelling medium. In the binary phase diagram with water the systems show a prominent laminary phase in the area with water contents of about 20-80% up to a maximum temperature of 35 degrees C. The phase behavior was also confirmed by thermal analysis, and the results of swelling measurements in water. Despite the relatively small hydrophilic part of the molecule, the swelling of the tested new cross-linked systems is more intensive in water than in nonpolar organic solvents. The swelling characteristics and phase behavior show a certain comparability to the human skin.

Fibrinolytic effects of pro-urokinase combined with low-dose urokinase compared to high-dose urokinase in patients with acute myocardial infarction

20 patients (6 females, 14 males) aged between 47 and and 75 years (mean: 62.6 yrs.) with acute myocardial infarction (onset of symptoms within 6 hours) were treated intravenously with either 200,000 U urokinase (UK) and 4.5 million U pro-urokinase (pro-UK) within 60 min (group I, N = 10), or 2.5 million U UK within 5 min (group II, N = 10). Blood samples for haemostatic and fibrinolytic function tests were taken prior to and repeatedly during the 24 hours following treatment. Peak fibrinolytic activity measured by fibrin plates was equivalent in both regimens. Average decreases, with lowest levels within 60 to 120 min following thrombolytic therapy, were observed of 27% and 70% for plasminogen, of 71% and 91% for alpha-2-antiplasmin, and of 20% and 74% for fibrinogen in group I and II, respectively. The reptilase time reached maximum values of 1.5- and 4.5-fold within 60 to 180 min. Peak levels of D-dimers and thrombin-antithrombin III complexes in group II were 2.6 and 3.2 times those of group I. After 24 hours, in contrast to group I, all these parameters still remained significantly different from pretreatment values in group II. These data indicate that, contrary to high-dose UK, pro-UK in combination with low-dose UK causes minor systemic fibrinolytic effects and is, therefore, assumed to be largely clot-specific, although the fibrinolytic potential is equivalent for both regimens.

Half-life of single-chain urokinase-type plasminogen activator (scu-PA) and two-chain urokinase-type plasminogen activator (tcu-PA) in patients with acute myocardial infarction

The pharmacokinetics of urokinase (two-chain urokinase-type plasminogen activator, tcu-PA) and single-chain urokinase-type plasminogen activator (scu-PA) were studied in 20 patients with acute myocardial infarction (AMI). Ten consecutive patients received 2.5 million units tcu-PA by bolus injection within 5 min during the first 6 h after AMI (group I). Ten further consecutive patients received 250,000 U tcu-PA within 5 min, followed by 4.5 million U scu-PA by intravenous infusion over 40 min (group II). An enzyme immunoassay was developed for urokinase antigen determinations, and a fibrin plate assay for determinations of fibrinolytic activity was applied. Using a 3-compartment model, in group I 98% of urokinase antigen were cleared with a half-life of 60.8 min. After scu-PA, urokinase antigen was cleared with half-lives (area under the curve in parentheses) of 6.9 min (74.8%), 26.5 min (23.6%), and 329.7 min (2.2%). The half-disappearance times of fibrinolytic activity were 18 and 8 min in group I and II, respectively. A more pronounced decrease of plasminogen was observed after tcu-PA.