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PubMed1993

Induction of follicular growth using recombinant human follicle-stimulating hormone in two volunteer women with hypogonadotropic hypogonadism.

OBJECTIVE: To examine the safety, tolerance, pharmacokinetics, follicular growth, and steroidogenesis after the administration of recombinant human FSH (Org 32489; Organon International, Oss, The Netherlands) in women with isolated hypogonadotropic hypogonadism. DESIGN: An open phase I multiple rising dose study with recombinant FSH in two hypogonadotropic but otherwise healthy women. The drug was administered intramuscularly one time per day for a maximum of 21 days, i.e., 75 IU for the first 7 days, 150 IU for the next 7 days, and 225 IU during the last 7 days. Treatment was discontinued if serum E2 was > or = 1,100 pmol/L and/or one or more growing follicle > 14 mm in diameter was observed. After the last recombinant FSH injection, subjects were monitored for another 3 weeks. SETTING: Specialist Reproductive Endocrinology and Infertility Unit. VOLUNTEERS: Two women with isolated hypogonadotropic hypogonadism who did not want to get pregnant anymore. MAIN OUTCOME MEASURES: Serum FSH, androstenedione (A), T, P, LH, follicular growth, and endometrial thickness. Safety parameters: blood pressure, heart rate, urinalysis, hematology, blood biochemistry, and antirecombinant FSH antibodies. RESULTS: Treatment with recombinant FSH resulted in dose-related increases of serum FSH. Both women showed follicular growth (diameter, 17 mm), whereas serum A concentrations were very low, and serum E2 concentrations rose to only 76.7 and 139.5 pmol/L, respectively. No antirecombinant FSH antibody formation or changes of safety variables were noted. CONCLUSION: This study in two women with hypogonadotropic hypogonadism is consistent with the two-cell theory that FSH alone can induce follicular growth. The low concentrations of A and E2 indicate the need for LH to induce appropriate steroidogenesis. It was also found that recombinant FSH is well absorbed, safe, and well tolerated after daily treatment for up to 21 days.

Adult↗
PubMed2004

Influence of photoperiod and temperature on reproductive mode in the Brine shrimp, Artemia franciscana.

Brine shrimp, Artemia, exhibit two modes of reproduction: oviparity (diapause cyst production) and ovoviviparity (live larvae release). Environmental conditions determining these developmental routes are poorly understood, so we investigated the effects of photoperiod and temperature on reproductive mode. Nauplii of A. franciscana were hatched from cysts produced in the Great Salt Lake, Utah, and raised in 2% natural sea salt water under photoperiods of 24, 14, 12, or 10 h at 28 degrees or 20 degrees C. Mating pairs of mature shrimp were isolated and reared continuously under those conditions. The mode of reproduction shown by each pair was determined daily throughout their life span, and found to be greatly affected by photoperiod, and less influenced by temperature. The relative degree of oviparity increased as the photoperiod became shorter at both temperatures. In contrast, the degree of ovoviviparity was higher as the photoperiod became longer at both temperatures. The critical photoperiod appears to be between 12 and 14 h. For all photoperiods examined, the degree of oviparity was higher at 28 degrees C than at 20 degrees C, whereas the degree of ovoviviparity was greater at 20 degrees C than at 28 degrees C.

Animals↗
PubMed1982

Dependence of reproduction rate on pressure as a hallmark of deep-sea bacteria.

Strains of bacteria in axenic culture were isolated from samples of depths between 1,957 and 10,476 m of the Pacific Ocean. All of the bacteria from this range of depths were barophilic. The pressure at which the rate of reproduction was maximal was found to be correlated with the depth of origin of the isolates.

Journal Article↗
PubMed2005

Phenotypic plasticity in Carlina vulgaris: effects of geographical origin, population size, and population isolation.

If phenotypic plasticity is under genetic control, it may vary in amount and pattern on a geographical scale, e.g. among different regions of a species' distribution. It may also differ between large and small or between less and more isolated populations, due to differences in genetic diversity. In a 2-year common garden study, the responses of several traits to drought and fertilizer treatments were studied in the grassland herb Carlina vulgaris. Individuals originating from populations of different size and degree of isolation in six European countries, representing "central" and "marginal" regions, were compared. Fertilizing had a negative effect on early plant survival, as well as on flowering probability in surviving plants. However, in those plants that flowered, fertilizing strongly increased mean number of flowerheads, flowerhead area (a correlate of seed number), and seed mass. Drought had generally weaker effects but enhanced survivorship, indicating that this treatment was closer to optimal conditions than were non-drought conditions. For some traits there were significant interactions of region x fertilizer, but the geographical pattern of reaction norms was inconsistent and lent no support to the hypothesis that central and marginal populations differ in overall plasticity. Population size and isolation had hardly any influence on treatment responses, but populations within regions differed in their mean response to fertilizing with regard to survival and flowering probabilities, as well as in their response to drought with regard to survival and total flowerhead area. It is concluded that response to raised nutrient levels is highly variable within populations, ranging from death to strongly increased reproductive output, but also among populations irrespective of size or isolation. This also goes for the response to water supply, though this variation shows a more unclear pattern. There is no evidence that small or isolated/marginal populations are less plastic than large or non-isolated/central populations, and the explanation for differences in treatment responses among plant populations should be sought in other population characteristics.

Analysis of Variance↗
PubMed2004

Characterization of Drosophila fruitless-gal4 transgenes reveals expression in male-specific fruitless neurons and innervation of male reproductive structures.

The fruitless (fru) gene acts in the central nervous system (CNS) of Drosophila melanogaster to establish male sexual behavior. Genetic dissection of the locus has shown that one of the fru gene's promoter, P1, controls the spatial and temporal expression of male-specific FruM proteins critical to determining stereotypical male sexual behavior. By using the Gal4-expression system, we show that a 16-kb fragment of the fru P1 promoter's 5' regulatory region drives the expression of Gal4 in a subset of FruM-expressing neurons within both the pupal and adult CNS. Colocalization of FruM and a Gal4-responsive reporter shows that the fru(P1)-gal4 fusion construct generates expression in both previously characterized FruM-expressing neurons as well as within cells of both the CNS and the peripheral nervous system that have not been demonstrated as FruM-expressing. Gal4-expressing neurons are shown to innervate abdominal organs directly relevant to fru function; specifically, the muscle of Lawrence (MOL) and the male internal reproductive organs. Innervations of the latter are shown to originate from identified FruM-serotonergic neurons. Furthermore, we show that the MOL neuromuscular junction is sexually dimorphic. Finally, we describe Gal4 expression in neurites innervating male reproductive structures that are hypothesized to be targets of fru function. Isolation of the regulatory sequences controlling the expression of fru in the CNS, therefore, provides a potent tool for the manipulation of FruM-expressing neurons and for understanding the cellular basis of Drosophila reproductive behavior.

Animals↗
PubMed1994

Aujeszky's disease virus strains with peculiar features.

Aujeszky's disease (AD) virus strains isolated from weak colostrum-deprived piglets were investigated for virulence in rabbits. Most of them (5 out of 9 investigated) proved avirulent. As clinical symptoms of AD were not observed during this period on the farms of origin, one can assume that the strains had a particular affinity for the pig fetus. It is proposed that the strains may be a result of recombination between the attenuated strains MK-35 (gI-) now in use as a live vaccine and MK-35 (gI+), used as a live vaccine until 3 years ago, as well as between the vaccine strain and a wild-type strain of AD virus, followed by the acquisition of tropism for the reproductive system. Virulent as well as avirulent strains were isolated in the same herd. The evaluation of a highly immunogenic killed AD vaccine in this complicated situation is recommended.

Animals↗
PubMed2002

Isolation increases milt production in goldfish.

Milt volume in goldfish is increased by female steroid and prostaglandin pheromones, by exposure to males with elevated gonadotropin levels, and by isolation from conspecifies. This study examined various aspects of the isolation effect on milt volume and serum gonadotropin II (GTH II). The latency of isolation-induced milt increase in this study (12-24 hr) was longer than the latencies to pheromone-induced milt increase in previous work (0.5-6.0 hr), was not affected by the time of day at which males were isolated, persisted for at least 72 hr in isolated males, and was terminated within 24 hr in males that were returned to groups. Isolated males maintained high milt production when separated from tank mates by a perforated barrier or when exposed to visual and odor cues from males in other tanks, suggesting that the unknown conspecific cues that maintain low milt production in groups operate at close range. Isolation appears to increase milt through a mechanism different from that mediating response to female pheromones because: (1) unlike female pheromones, which consistently increase serum GTH II, no isolation or regrouping treatment in this study affected male GTH II concentration; and (2) the effects of isolation and of exposure to the female pheromone 17 alpha, 20 beta-dihydroxy-4-pregnen-3-one (17,20 beta-P) are additive. Finally, males that were previously isolated or exposed to 17,20 beta-P increased milt (but not GTH II) in grouped males, suggesting that the effects of isolation and pheromone exposure can indirectly stimulate male conspecifics. Although the biological function of the isolation effect is not clear, we propose that it illustrates the effect of removal from inhibitory cues normally received from male conspecifies.

Animals↗
PubMed2006

A dehydration-inducible gene in the truffle Tuber borchii identifies a novel group of dehydrins.

BACKGROUND: The expressed sequence tag M6G10 was originally isolated from a screening for differentially expressed transcripts during the reproductive stage of the white truffle Tuber borchii. mRNA levels for M6G10 increased dramatically during fruiting body maturation compared to the vegetative mycelial stage. RESULTS: Bioinformatics tools, phylogenetic analysis and expression studies were used to support the hypothesis that this sequence, named TbDHN1, is the first dehydrin (DHN)-like coding gene isolated in fungi. Homologs of this gene, all defined as "coding for hypothetical proteins" in public databases, were exclusively found in ascomycetous fungi and in plants. Although complete (or almost complete) fungal genomes and EST collections of some Basidiomycota and Glomeromycota are already available, DHN-like proteins appear to be represented only in Ascomycota. A new and previously uncharacterized conserved signature pattern was identified and proposed to Uniprot database as the main distinguishing feature of this new group of DHNs. Expression studies provide experimental evidence of a transcript induction of TbDHN1 during cellular dehydration. CONCLUSION: Expression pattern and sequence similarities to known plant DHNs indicate that TbDHN1 is the first characterized DHN-like protein in fungi. The high similarity of TbDHN1 with homolog coding sequences implies the existence of a novel fungal/plant group of LEA Class II proteins characterized by a previously undescribed signature pattern.

Amino Acid Sequence↗
PubMed2001

Mating system and reproductive skew in the black rhinoceros.

Only approximately 2600 black rhinoceros survive today, mainly in small, isolated populations of < 100 animals. The management of remaining black rhinoceros populations aims at preserving natural levels of genetic relatedness and optimizing breeding success, which requires an accurate knowledge of the mating system, reproductive skew and effective population size. DNA was extracted from faecal samples from a community of 35 wild black rhinoceros, and microsatellites were used to characterize patterns of paternity of 19 offspring born from eight females in this community. Paternity could be ascribed unequivocally for each offspring. Although our conclusions must be considered tentative, we present the first genetic evidence that black rhinoceros males are polygynous, with a high variance in reproductive success. We also describe a noninvasive management tool that can be used for the genetic management of this critically endangered species, both in the wild and in captivity.

Animals↗
PubMed2005

An epididymal form of cauxin, a carboxylesterase-like enzyme, is present and active in mammalian male reproductive fluids.

Mass spectrometric analysis of a prion protein (PrP)-containing complex isolated from ram cauda epididymal fluid revealed a protein that showed homology to a carboxylesterase-like protein previously identified in cat urine (cauxin). Using anti-cauxin antibodies, immunoreactive bands were detected in corpus and cauda epididymal fluid from all mammals tested (ram, boar, mouse, and cat). In the ram, the protein was also present in seminal fluid but not found to be associated with sperm. The bands reacting with the anti-cauxin antibody coincided with those having esterase activity in a zymographic assay and its levels paralleled the esterase activity of native epididymal fluids. A partial nucleotide sequence of 1143 bp, corresponding to 380 amino acids, was obtained by RT-PCR amplification from total RNA from the corpus epididymis (zone 6). The deduced protein sequence shows a high degree of homology (up to 90%) with the different cauxin proteins found in databases but only up to 60% with other known carboxylesterases. By PCR, strong mRNA expression was found in the corpus and cauda epididymis, while the testis, kidney, and caput epididymis had low expression. No mRNA was detected in the lung, heart, or liver. These data demonstrate that an epididymal form of the cauxin enzyme is secreted into mammalian epididymal fluid. In the ram, it is associated with a high molecular-weight PrP-associated complex and may be responsible for the majority of the esterase activity in the cauda epididymal fluid of this species.

Amino Acid Sequence↗
PubMed1996

Differential expression of two beta-galactoside-binding lectins in the reproductive tracts of pregnant mice.

Two beta-galactoside-binding proteins were isolated from uteroplacental complexes of pregnant mice and identified as the S-Lac lectins galectin-1 and galectin-3. The spatiotemporal pattern of appearance of those proteins was determined by immunocytochemistry. Galectin-1 was present in all tissue compartments of the uterus except the luminal and glandular epithelium. It was found in the uteri of animals from all preimplantation stages of pregnancy, as well as in those from nonpregnant, ovariectomized, or sexually immature animals. After implantation of the embryo, cells of the decidua basalis were labeled, as were granular metrial gland cells, all trophoblastic elements of the placenta, the myometrium, and nondecidualized endometrium. By contrast, there was little evidence of galectin-3 in the uteri of nonpregnant animals or during the preimplantation stages of pregnancy. However, immunoreactive material was observed in endometrial cells of the primary decidual zone immediately after implantation and at later stages of pregnancy in the decidua basalis, metrial gland, and all trophoblastic elements of the placenta. There was no evidence of galectin-3 in the myometrium or nondecidualized endometrium. After parturition, amounts of galectin-3 in the endometrium and metrial triangle appeared to decrease as the implantation sites were resorbed. These data suggested that the function of galectin-1 is one of tissue maintenance, whereas the function of galectin-3 is related specifically to pregnancy.

Amino Acid Sequence↗
PubMed1998

Leptospira fainei sp. nov., isolated from pigs in Australia.

Pathogenic leptospires can be causative agents of reproductive problems in pigs. Cultures of uteri and kidneys from two pigs herds in New South Wales and Victoria (Australia) yielded five strains identified as Leptospira on morphological and cultural grounds. Phenotypic characteristics (growth at 13 and 30 degrees C, growth in the presence of 8-azaguanine) were intermediate between those of pathogenic and saprophytic leptospires. No cross-agglutination was observed with reference antisera representing the 24 pathogenic serogroups and the main saprophytic ones. Antiserum against one of the strains did not agglutinate reference stains representative of any serogroup. This provided evidence of a new serovar, designated hurstbridge. Genomic characterization of the five strains was achieved using five molecular approaches. Mapped restriction site polymorphisms in the rrs (16S rRNA) gene were not related to those of any reference strains. Arbitrarily primed PCR fingerprints suggested clonality of the five strains. The strains all showed an identical and unique PFGE profile. PCR, using primers specific for the rrs gene of pathologic leptospires, amplified corresponding sequences from the strains. DNA-DNA hybridization (and reciprocal experiments) using the S1 nucleas/TCA method was performed between one of the strains and the reference strains of Leptospira species. The homology ranged from 0 to 36% (the latter being was Leptospira inadai) thus satisfying the criterion of a new species, Leptospira fainei (type strain BUT 6T). Phylogenetic analysis of 16S rRNA sequence showed that L. fainei and L. inadai formed a clade separate from the previously recognized 'saprophyte' and 'pathogen' clades.

Animals↗
PubMed1980

Distribution of acrosin inhibitors in bull reproductive tissues and spermatozoa.

Antisera against two low molecular weight acrosin inhibitors, isolated from bull seminal plasma (BUSI I and BUSI II), were prepared by immunizing rabbits and hamsters. Antisera to BUSI I and BUSI II cross-reacted immunologically with low intensity. Using immunological techniques BUSI I and BUSI II could be demonstrated in the tissues and fluids of bull seminal vesicles and ampullae and on the acrosomes of ejaculated and ampullar spermatozoa. BUSI II was also detected in the epididymal fluid and on the acrosomes of epididymal spermatozoa. Antisera to both inhibitors cross-reacted with boar seminal vesicle fluid and ram seminal plasma. There was no cross-reaction with the components of blood serum.

Acrosin↗
PubMed1983

Antigenic and biological criteria of differentiation of the newly isolated strains of respiratory syncytial virus.

Respiratory syncytial (RS) virus strains isolated in different years varied by their antigenic and biological properties. The lowest degree of relatedness was found between the "street" virus and the prototype Long strain; the highest occured among the isolates from a given isolation period. Based on the mean indices of efficiency of the virus reproduction in human embryo lung (HEL) cells at 37 degrees C and 39 degrees C as well as on the degree of virus sensitivity to reference antibodies, the isolates from various years could be divided into three groups, namely high, mild and low virulent strains. The incidence of RS virus infections in children depended on the strain characteristic of virus population circulating in a community of children during the long-term observation period of 1976-1979. Cyclic variation was found in isolation rates of RS viruses; the duration of each cycle in different years ranged from 21 to 41 days. The variability of isolation cycles and the frequency of RS virus reinfections were closely related to the biological characteristics of circulating virus strains.

Antigens, Viral↗
PubMed1984

Glycoconjugates in the reproductive system of female rabbits in physiological estrogenic conditions.

Glycopeptide fractions were isolated from the uteri and oviducts of female rabbits in physiological estrogenic conditions. Both from the uterus and the oviduct considerably heterogeneous heteropolysaccharides were extracted, formed by hexoses, hexosamines, fucose, sialic acid, uronic acids and sulphates. During the estrus stage an increase is found in all glucide components, except for sialic acid, which, on the contrary, decreases. This decrease has been explained on the basis of histochemical data obtained in previous researches.

Animals↗
PubMed1999

Possible functions of oxytocin/vasopressin-superfamily peptides in annelids with special reference to reproduction and osmoregulation.

Annetocin is an earthworm oxytocin-related peptide that we previously isolated from the whole body of a lumbricid earthworm Eisenia foetida. We have reported that annetocin induces egg-laying-like behaviors in E. foetida and a gnathobdellid leech, Whitmania pigra, when it is injected into the respective animals. The present study was undertaken to probe physiological functions of invertebrate oxytocin-vasopressin-superfamily peptides with special reference to reproductive and osmoregulatory events in which vertebrate peptides of this superfamily are involved. Annetocin, Lys-conopressin (a leech vasopressin-related peptide) and two analog peptides, [Tyr(3)]-annetocin ((3)Y-annetocin) and [Phe(3)]-annetocin ((3)F-annetocin), were compared for their activities to induce egg-laying-like behavior and to change body weight as a measure of water balance in the leech W. pigra. Injection of annetocin, Lys-conopressin, and (3)F-annetocin caused both egg-laying-like behavior and reduction of body weight in the animals, but (3)Y-annetocin induced neither. Furthermore, leeches in the non-breeding season responded to peptides less conspicuously than those in the breeding season. Such a concomitant induction of egg-laying-like behavior and body-weight reduction suggests that these two phenomena are unitary and might be accounted for by the fact that egg-laying in leeches and earthworms is accompanied by secretion of a large quantity of mucus, which should significantly contribute to body-weight loss. J. Exp. Zool. 284:401-406, 1999.

Amino Acid Sequence↗
PubMed1979

Isolation by distance: reply to Lalouel and Morton.

Lalouel's assertion that I misinterpreted Malécot's work on isolation by distance may or may not be correct. If so, my assertions of error in Malécot's derivation are wrong, although they do apply to others who have used models involving a spatial continuum. Lalouel's other claims of error in my derivations of the consequences of a spatially continuous model of population reproduction and migration are incorrect, with the exception of one isolated misprint.

Genetics, Population↗
PubMed2006

Identification of a novel pituitary-specific chicken gonadotropin-releasing hormone receptor and its splice variants.

In all vertebrates, GnRH regulates gonadotropin secretion through binding to a specific receptor on the surface of pituitary gonadotropes. At least two forms of GnRH exist within a single species, and several corresponding GnRH receptors (GNRHRs) have been isolated with one form being pituitary specific. In chickens, only one type of widely expressed GNRHR has previously been identified. The objectives of this study were to isolate a chicken pituitary-specific GNRHR and to determine its expression pattern during a reproductive cycle. Using a combined strategy of PCR and rapid amplification of cDNA ends (RACE), a new GNRHR (chicken GNRHR2) and two splice variants were isolated in domestic fowl (Gallus gallus domesticus). Full-length GNRHR2 and one of its splice variant mRNAs were expressed exclusively in the pituitary, whereas mRNA of the other splice variant was expressed in most brain tissues examined. The deduced amino acid sequence of full-length chicken GNRHR2 reveals a seven transmembrane domain protein with 57%-65% homology to nonmammalian GNRHRs. Semiquantitative real-time PCR revealed that mRNA levels of full-length chicken GNRHR2 in the pituitary correlate with the reproductive status of birds, with maximum levels observed during the peak of lay and 4 wk postphotostimulation in females and males, respectively. Furthermore, GnRH stimulation of GH3 cells that were transiently transfected with cDNA that encodes chicken GNRHR2 resulted in a significant increase in inositol phosphate accumulation. In conclusion, we isolated a novel GNRHR and its splice variants in chickens, and spatial and temporal gene expression patterns suggest that this receptor plays an important role in the regulation of reproduction.

Amino Acid Sequence↗