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PubMed1989

Isolation and identification of trophoblast lymphocyte cross-reactive (TLX) antigens from human lymphocytes.

It has been proposed that allotypic trophoblast lymphocyte cross-reactive (TLX) antigens are involved in the maintenance of normal human reproduction. Despite such a potentially important role for TLX antigens, isolation of human TLX proteins has not yet been reported. As an initial step toward elucidation of the structure and function of TLX antigens, we have isolated TLX proteins from Lubrol-solubilized lymphocytes (termed "wTLX") by anti-trophoblast membrane-Sepharose immunoaffinity chromatography. Using Ouchterlony immunodiffusion and immunoelectrophoresis, we have identified an immunoreactive wTLX antigen which forms a single immunoprecipitation line against absorbed anti-trophoblast membrane. From 17.5% sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblot analyses, a 35-kDa band was determined to be a major protein band in the immunoaffinity-isolated wTLX fraction, along with multiple minor wTLX bands. These results suggest the possible existence of antigenic polymorphism of TLX, with predominant expression of the 35-kDa wTLX antigen in lymphocytes. The strong staining of the TLX antigens with Coomassie Brilliant Blue and Amido Black indicates they are largely proteins. Co-isolation of beta 2-microglobulin in the immunoaffinity-isolated wTLX pool could imply that the wTLX antigens may be unique class I HLA-like antigens. This possibility has yet to be resolved.

Autoantigens↗
PubMed2001

Trichinella pseudospiralis populations of the Palearctic region and their relationship with populations of the Nearctic and Australian regions.

Since few non-encapsulated isolates of Trichinella have been studied to date, their level of differentiation from encapsulated species and the taxonomic value of the observed polymorphisms remain to be determined. To this end, biological, biochemical and molecular data from 11 isolates of Trichinella pseudospiralis and one isolate of Trichinella papuae were examined using the broad group of encapsulated species and genotypes for comparison. Single-worm cross-breeding experiments and reproductivity capacity indices revealed F1 progeny only among T. pseudospiralis isolates from different zoogeographical regions, whereas no F1 were produced when T. pseudospiralis was crossed with T. papuae. Furthermore, unlike T. pseudospiralis, T. papuae failed to infect chickens. Comparative analysis of 12 allozymes revealed a single difference between Nearctic and Australian isolates of T. pseudospiralis, but substantial differences when compared with T. papuae (i.e. two unique and six diagnostic markers). Molecular studies involving mitochondrial-derived genes encoding cytochrome oxidase I and the large subunit ribosomal DNA indicated a high level of sequence similarity among T. pseudospiralis isolates; however, a concomitantly high level of variation was observed in expansion segment five of the genomic large subunit ribosomal DNAs among T. pseudospiralis isolates and between this species and T. papuae. Collectively, these results demonstrate high uniformity among isolates of T. pseudospiralis from Eurasia and polymorphism among isolates of T. pseudospiralis belonging to different zoogeographical regions; the results corroborate the classification of T. papuae as a differentiated species.

Animals↗
PubMed1987

[2 strains of swine parvoviruses isolated from aborted fetuses].

Two hemagglutinating virus strains were isolated (in primary cell cultures of pig kidneys) from viscera of aborted swine fetuses. A number of serologic, cytologic, physico-chemical, and laboratory investigations with the strains revealed that they belonged to the group of porcine parvovirus (PPV). The isolation of SPV from aborted fetuses pointed to the fact that the disease had been widespread among the swine population and plays a part in reproduction disturbances that have come to be known recently. The isolated strains did not produce a clear and distinguishable cytopathic effect in inoculated cell cultures. They, however, could be demonstrated in the cultures indirectly through cytologic investigation (the demonstration of intranuclear inclusion bodies, type B after Cowdry, through hemagglutination tests, and via immunofluorescent microscopy.

Abortion, Veterinary↗
PubMed1991

Phospholipase C activity in microorganisms associated with reproductive tract infection.

Phospholipase C (lecithinase or phosphatidylcholine phosphorylase) catalyzes the hydrolysis of lecithin into phosphorylcholine and 1,2-diglyceride. Bacterial production of phospholipase C may damage reproductive tract tissues by both direct and indirect mechanisms. Use of the synthetic substrate p-nitrophenylphosphorylcholine phospholipase C activity was determined in 204 isolates representative of those found in female genital tract. Multiple aerobic (28%) and anaerobic (28%) reproductive tract microorganisms showed phospholipase C activity. Phospholipase C-producing isolates included strains of Bacteroides fragilis, B. bivius, B. thetaiotaomicron, Gardnerella vaginalis, and group B streptococcus. Phospholipase C activity was heterogenous; not all isolates that belong to a particular species showed activity. Phospholipase C production may be a possible virulence factor produced by a number of microflora commonly implicated in various reproductive tract infections or conditions, as well as in some instances of preterm birth.

Bacteria, Aerobic↗
PubMed2001

Molecular biology of channel catfish gonadotropin receptors: 1. Cloning of a functional luteinizing hormone receptor and preovulatory induction of gene expression.

There is little known about the molecular biology of piscine gonadotropin receptors, and information about gene expression during reproductive development is particularly lacking. We have cloned the LH receptor (LHR) in the channel catfish (cc), and examined its gene expression throughout a reproductive cycle. A cDNA encoding the receptor was isolated from the testis using reverse transcription-polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends procedures. It encoded a 696-amino acid protein that showed the greatest homology (46-50% identity) with the known LHRs and lesser similarity with FSH receptors and thyroid-stimulating hormone receptors (44-47% and 42-44% identity, respectively). In addition, two characteristics unique to the LHRs were conserved in the cloned receptor and the encoding gene: presence of an intron corresponding to intron 10 in mammals and turkey and occurrence of a double cysteine residue in the cytoplasmic tail for potential palmitoylation. The ccLHR gene was well expressed in the gonads and kidney and merely detectable in the gills, muscle, and spleen. The isolated cDNA encoded an active ccLHR protein, as the recombinant receptor expressed in COS7 cells activated a cAMP response element-driven reporter gene (luciferase) upon exposure to hCG in a dose-dependent manner. Seasonal changes in the ovarian expression of the ccLHR gene, as examined by measuring the transcript abundance by quantitative real-time RT-PCR, remained rather low during most of the reproductive cycle but was acutely induced around the time of spawning. This pattern of expression correlates well with the reported expression of its ligand (LH) in fishes and concurs with the notion that LH is a key regulator of the periovulatory maturational events.

Amino Acid Sequence↗
PubMed1998

Horizontal transmission of feline immunodeficiency virus with semen from seropositive cats.

The AIDS virus of cat species, feline immunodeficiency virus (FIV), has been used extensively as an animal model of HIV-1 infection. This felid lentivirus shares many molecular and biochemical traits with HIV-1 and causes similar immunologic and clinical perturbations, most notably CD4+ cell loss, impaired cell-mediated immunity and increased susceptibility to opportunistic pathogens. Previous reports have shown that FIV is transmitted horizontally by biting and vertically in utero and through nursing. Our objective was to determine whether FIV could be venereally transmitted in domestic cats. In the first experiment, susceptibility of the female reproductive tract to mucosal transmission of the FIV isolate, NCSU1, was demonstrated via intravaginal inoculation with infected cultured cells. We next identified virus in electroejaculates from asymptomatic, chronically FIV-NCSU1-infected, adult males. A fragment of FIV gag provirus DNA was detected by nested polymerase chain reaction (PCR) in nonfractionated seminal cells and in swim-up sperm preparations. Additionally, replication-competent virus was isolated from cell-free seminal plasma and seminal cells by co-cultivation with a feline CD4+ T-cell line. In the third study, queens were artificially inseminated via an intrauterine laparoscopic technique with electroejaculates from FIV-NCSU1-infected males. Of six inseminations carried out with fresh semen, three resulted in infection of queens. Lastly, immunohistochemical studies identified potential virus target cell populations in normal female reproductive tissues. In conclusion, these experiments indicate that FIV infection in domestic cats may provide a unique small animal model of sexual transmission of HIV-1.

Animals↗
PubMed2003

Comparison of intestinal mucosa homogenate and pure culture of the homologous Lawsonia intracellularis isolate in reproducing proliferative enteropathy in swine.

Little information is available on reproduction of proliferative enteropathy (PE) using a virulent pure culture of Lawsonia intracellularis. Reproduction of the disease using PE-diseased mucosa homogenates, however, is well-characterized. The aims of this study were to evaluate and compare clinical signs, growth performance and the severity of lesions in pigs inoculated with intestinal mucosa homogenate or pure culture of the homologous L. intracellularis isolate. Five-week-old pigs were inoculated with pure culture of L. intracellularis (isolate PHE/MN1-00; n=10), PE-diseased mucosa (n=10), or control media (n=4). The L. intracellularis isolate PHE/MN1-00 used in the pure culture inoculum was extracted from a fragment of the same intestine used to prepare the mucosa homogenate. Clinical signs and growth performance were evaluated throughout the study. Fecal shedding was evaluated in all animals weekly during the experiment. All animals were euthanized 22 days post-inoculation, the intestines were examined grossly and histologically. Results showed that both the infection procedures reproduced clinical disease, macroscopic and histologic lesions typical of PE. Fecal shedding was detected in animals in both challenge groups. In conclusion, the L. intracellularis isolate PHE/MN1-00 reproduces typical clinical signs and lesions of PE similar to the homologous infection with an intestinal mucosa homogenate.

Animals↗
PubMed1994

A multiple fission-like mode of asexual reproduction in Blastocystis hominis.

A non-axenic and an axenic isolate of Blastocystis hominis have been induced to form cysts in vitro using an encystation medium. The morphology of the parasite at different time points was observed by scanning electron microscopy. In day-2 cultures the cysts were spherical and had a non-uniform, coarse outer surface around the body. A deep, pore-like opening was seen in some of the parasites. Most of the cysts from day-4 and day-6 cultures ruptured, revealing small, uniformly sized spherical bodies occurring in grape-like clusters. Acridine orange staining confirmed that these bodies were the progeny of Blastocystis hominis. A multiple fission-like reproduction process giving rise to many daughter Blastocystis occurs within the cyst.

Acridine Orange↗
PubMed1994

The island syndrome in rodent populations.

Populations of rodents isolated on islands often show systematic differences in demography, reproduction, behavior, and morphology when compared to mainland populations. These differences, termed the island syndrome, include higher and more stable densities, better survival, increased body mass, and reduced aggressiveness, reproductive output, and dispersal. We synthesize information in the literature on island rodent populations and construct a conceptual model to explain the island syndrome. Population density and other manifestations of the island syndrome are predicted to increase with island isolation and to decrease with island area. The effect of isolation is direct by limiting dispersal, while the effect of area is less direct. As area increases, predators, competitors, and habitat structure increase in diversity. We suggest that the intensity or absence of density-depressing factors (primarily predation in communities comprised of only a few morphologically and trophically divergent species) is primarily responsible for the area effect and serves as a principal factor differentiating island from mainland populations of rodents. Other characteristics associated with the island syndrome may be the result of both short-term and long-term processes or responses. Short-term responses include reproductive, body size, and behavioral changes that may be phenotypic reaction norms in response to higher island densities. Thus, higher densities lead to reduced reproductive output, which then leads to greater body size. Initial behavioral differences may be owing to better survival and reduced dispersal, which result in less population turnover, greater neighbor familiarity, and less aggression. Long-term changes may be due to directional selection for reduced dispersal, increased body size in response to increased intraspecific competition, reduced reproductive output (smaller litters and delayed maturation) in response to reduced mortality schedules, and reduced aggressiveness. While the model is specific to rodent populations, the conclusions may be applicable to other systems if characteristics such as body size, vagility, and community composition are considered.

Animals↗
PubMed1985

Ovarian lesions in heifers exposed to infectious bovine rhinotracheitis virus by non-genital routes on the day after breeding.

Twelve heifers were exposed to either a Colorado infectious bovine rhinotracheitis (IBR) virus isolate or an Iowa IBR isolate obtained from a bovine respiratory disease outbreak. All inoculations were made on the day after the heifers had been in estrus and bred by an IBR virus-negative bull. Pairs of heifers were inoculated with each virus isolate intravenously, intramuscularly or exposed by aerosol. The heifers were killed 11-15 days after inoculation and their reproductive tracts and ovaries subjected to virological and pathological study. Virus was isolated from the ovaries of all 4 heifers inoculated intravenously and from 3 of the 4 heifers inoculated intramuscularly, but not from the ovaries of heifers exposed by aerosol. Virus isolations and lesions were, with only 1 exception, confined to the ovary containing the corpus luteum. In ovaries from which IBR virus was isolated, lesions in the corpus luteum ranged from focal necrosis and infiltration of mononuclear cells to diffuse hemorrhage and necrosis. Most of these ovaries also had necrotic follicles and a diffuse mononuclear cell accumulation in the stroma. Lesions were not found in ovaries from which IBR virus was not isolated. It was concluded that lesions are readily induced in the ovaries of post-estrus heifers as a result of hematogenous spread of IBR virus and suggest that the differences in lesion development observed with the 3 routes are related to whether or not a viremia occurred.

Animals↗
PubMedDate not supplied

Ultrastructure and viability of isolated bovine preantral follicles.

Techniques for the isolation of ovarian follicles and maturation of oocytes in vitro have enormous reproductive potential. Preservation of normal tissue function is vital. This study emphasizes the ultrastructure and viability of mechanically isolated bovine small (diameter 40-100 microm) preantral and large (140-450 microm) preantral/early antral follicles. Viability studies were performed for small preantral follicles. The presence of esterase activity, active mitochondria and dead cells served as parameters of oocyte and granulosa cell viability. After 1 day of culture, all follicles had a viable granulosa, displaying active mitochondria and/or esterase activity in all their cells, although a few (generally <5) dead granulosa cells were present in 17% of the follicles. Of the oocytes, 35 and 80% had esterase activity and active mitochondria respectively, whereas 8% appeared dead. The percentages of oocytes showing esterase activity and active mitochondria decreased during culture, whereas the percentage of follicles with dead oocytes or dead granulosa cells strongly increased. More than 90% of the isolated small follicles showed a poor ultrastructure, especially of their oocyte, which points to a negative selective isolation of poor follicles in the present study and/or an isolation procedure-induced damage of follicles. With respect to large preantral follicles, 42% of those distributed in the cortex and 64% of those isolated and cultured for 1 day had a poor ultrastructure. In contrast with the small ones, the percentage of ultrastructurally poor large preantral follicles had decreased to 27% after 5 days of culture, possibly due to better isolation and culture conditions. It is recommended to use ultrastructural and/or viability cell markers for in-vitro grown follicles to evaluate their quality, and particularly that of their oocytes.

Animals↗
PubMed1983

Prevalence of cytomegalovirus and herpes simplex virus in human semen.

Cytomegalovirus was isolated from semen in 4 of 170 males seeking evaluation at the Reproductive Medicine Clinic at Prince Henry's Hospital, and from 1 of 40 healthy university students. All initial isolates were from specimens with abnormal semen analysis (P less than 0.01). Herpes simplex virus was not isolated from any sample.

Cytomegalovirus↗
PubMed1970

Sexual reproduction on Geotrichum candidum.

A perfect state of Geotrichum candidum was isolated from soil in Puerto Rico. Wild-type cultures are self-fertile but give rise to self-sterile, cross-fertile mating types morphologically different in some respects from the wild type. This discovery of the perfect state of G. candidum and its unique pattern of sexuality may contribute to knowledge of its ecology, the origin of pathogenic races, and speciation.

Mitosporic Fungi↗
PubMed2000

Characterization of a novel gene encoding a putative single zinc-finger protein, ZIM, expressed during the reproductive phase in Arabidopsis thaliana.

By differential screening of an arrayed normalized cDNA library from the inflorescence apex in Arabidopsis, a cDNA clone having a deduced amino acid sequence with a motif for a zinc finger was isolated as one of the genes expressed specifically in the reproductive phase. The deduced protein has a modular structure with a putative single C2-C2 zinc-finger motif distantly related to a GATA-1-type finger, a basic region with a sequence resembling a nuclear localization signal, and an acidic region. The gene seemed to have been formed by the exon-shuffling during its molecular evolution, since individual domains are encoded by discrete exons. RNA gel blot analysis showed its expression in shoot apex and flowers in the reproductive phase. The gene was named ZIM for Zinc-finger protein expressed in Inflorescence Meristem. The nuclear localization of ZIM was detected using GFP as a reporter. These results suggest that ZIM is a putative transcription factor involved in inflorescence and flower development.

Amino Acid Sequence↗
PubMed1998

Bacterial infection and endotoxin in female reproductive tract in rats: correlation with the developmental status of preimplantation embryos.

During mammalian preimplantation development, a substantial numbers of embryos are believed to be lost for reasons that are unclear. Using female rats, we investigated whether the developmental status of embryos is influenced by bacterial infection and endotoxin in the reproductive tract. From the vagina of cycling rats (n = 11), 21 bacterial isolates were identified; they were Streptococcus faecalis (S. faecalis; 38%), Escherichia coli (E. coli; 19%), Acinetobactor calcoaceticus (A. calcoaceticus; 14%), and coagulase negative staphylococcus (14%), Micrococcus sp. (5%), Bacillus subtilis (B. subtilis; 5%) and Proteus vulgaris (P. vulgaris; 5%). From the vagina of day 4 pregnant rats (n = 12), 26 isolates were identified; they were S. faecalis (23%), A. calcoaceticus (23%), E. coli (15%), Micrococcus sp. (15%), B. subtilis (8%), P. vulgaris (4%), Staphylococcus aureus (4%), beta-hemolytic streptococcus (4%) and Pseudomonas aeruginosa (4%). Gram negative bacteria found in the vagina of cycling and day 4 pregnant rats were 38% and 46%, respectively. In both, bacterial load was 10(3)-10(5) colony forming units and there was no association with the abnormality of the recovered embryos. However, in two day 4 pregnant animals, pathogenic bacteria (Staphylococcus aureus and beta-hemolytic streptococcus) were isolated and embryos recovered from them were degenerated and deformed. The vagina of day 9 pregnant animals (n = 7) were, however, sterile. Consistently, in all animals, the upper reproductive tract (uterus and oviduct) was devoid of any bacteria and no anaerobic bacteria were isolated from any part of the tract. The levels of endotoxin in the vagina of cycling and day 4 pregnant rats were 1.35 +/- 0.1 and 1.17 +/- 0.1 endotoxin units (EU), respectively. It was undetectable in the oviduct and uterus of all animals (n = 5) except one which showed high levels of endotoxin in uterus (4.5 EU) and oviduct (2.2 EU) and the animal also produced degenerated and deformed embryos. These results indicate that common bacterial flora of vagina may not affect embryo development and the presence of pathogenic bacteria in the vagina and/or endotoxin in reproductive tract could be detrimental to viability of gametes and preimplantation embryos in rats.

Animals↗
PubMed2000

Spatial distribution of allozyme polymorphisms following clonal and sexual reproduction in populations of Rhus javanica (Anacardiaceae).

Rhus javanica L. (Anacardiaceae), a dioecious tree with both sexual reproduction and clonal growth, is widely distributed in warm temperate, subtropical, and tropical regions in east Asia. We used allozyme loci and spatial autocorrelation statistics to examine clonal structure and the spatial distribution of allozyme polymorphisms in two Korean populations. Populations of the species maintain moderate levels of allozyme variability (mean He=0.175, GST=0.060), and high levels of multilocus genotypic diversity (mean DG=0.971). Clone-pair distances ranged from 1.4 m to 57.4 m, and had high mean values of 24.0 m and 25.6 m in the two study populations. Approximate genetic patch widths were inferred to be 23-25 m. The results indicated that within populations there is moderate (one study population) or no (other study population) spatial genetic structure among sexually reproduced individuals, and vegetatively reproduced genotypes also are almost randomly distributed. The spatial genetic structure among sexually reproduced trees in the one case is probably caused by limited pollen dispersal in that population, and the lack of structure in the other probably results from the short time elapsed since founding. It appears that clonal reproduction also does not contribute substantially to genetic isolation by distance neither among the sexually reproduced individuals nor the total population. Ramets often establish long distances from their progenitors and thus do not substantially increase the degree of local consanguineous matings.

Genetic Markers↗
PubMed2003

In vitro anti-influenza virus activity of isoquinoline alkaloids from thalictrum species.

The in vitro anti-influenza virus effects of some isoquinoline alkaloids, isolated from Thalictrum species (Ranunculaceae), growing in Mongolia and Sweden have been studied. (-)-thalimonine (Thl) and (-)-thalimonine N-oxide, isolated from the Mongolian plant T. simplex, inhibited markedly the influenza virus reproduction in vitro; thalictuberine N-oxide was less effective. The synthetic analogues of Thl as well as the rest of the tested alkaloids, isolated from T. foetidum and T. flavum, were not active. At a concentration range between 0.1 - 6.4 microM Thl inhibited viral reproduction in a selective and specific way.

Alkaloids↗