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PubMed1999

Analysis of cellular immune response in pigs recovered from porcine respiratory and reproductive syndrome infection.

The cellular immune response to a European isolate of porcine reproductive and respiratory syndrome (PRRS) virus in animals recovered from the experimental infection has been studied in vitro. Peripheral blood mononuclear cells (PBMC) from these pigs proliferated specifically when they were stimulated with PRRS virus. This response was not detectable until 4 weeks after inoculation and remained for more than 3 months. Addition of blocking monoclonal antibodies to the cultures showed that this proliferation was mainly dependent on CD4(+) cells with the participation of SLA-class II molecules. T-cell cultures established by stimulating responding cells with PRRS virus and maintained in culture for up to 3 weeks showed an increase of CD8(+) CD4(+) and CD4(-) CD8(+) subsets within activated cells, gated according to their light scatter parameters, whereas CD4(+) CD8(-) cells declined along the time in culture. Within the activated cells, those expressing the TcR gammadelta receptor also increased, being most of them also positive for the CD8 marker. By RT-PCR, T-cells responding to the virus showed a Th1 type cytokine production pattern. During the culture period the cytotoxic activity against K-562 cells increased from 15 to 35% of specific lysis. This cellular immune response may play a relevant role in the clearance of PRRS virus and the recovery of the infection.

Animals↗
PubMed1993

Estrogen receptors, estradiol, and diethylstilbestrol in early development: the mouse as a model for the study of estrogen receptors and estrogen sensitivity in embryonic development of male and female reproductive tracts.

To date, there is no conclusive evidence that ERs are present in preimplantation embryos. There are reports that estrogen is made by the rabbit blastocyst (61), and estrogens have been used to induce implantation in mice (62), but whether estrogens act through ERs in the embryo or in the maternal uterus is not known. ERs may be present in early embryos, but if so, levels are below the methods of detection used thus far. Perhaps with more sensitive immunodetection methods, it may be possible to detect ERs in embryos if they are present. Using PCR, messenger RNA for ER has been detected as early as the oocyte stage in mouse embryos (Q. Hou and J. Gorski, unpublished results). This was confirmed recently by Wu et al. (83a). Figure 7 shows a model for the pattern of ER expression in the developing mouse fetus based on the various reports discussed in this review. ERs are present in the 10-day mouse fetus, possibly in the developing ambisexual reproductive tract. Analysis of seven individual 10-day-old fetuses taken from the same litter showed similar levels of an immunostained protein the size of the ER in each fetus (57). The pattern of expression of ER between implantation and the development of the reproductive tract may be the same in male and female mice. Estrogen, acting through ERs, may be one factor (of many) that determines which cells are destined to be part of the indifferent reproductive tract. We were not able to isolate fetal mouse reproductive tracts at an indifferent stage (day 10) due to their very small size. One way to study ER in the indifferent reproductive tract would be to examine these tissues in a larger animal, such as the bovine, using similar immunodetection methods. The distribution of ER in the fetal mouse reproductive tract on fetal days 13 (before sexual differentiation) and 15 (initiation of sexual differentiation) is similar in males and females (71, 72). Thus, estrogen does not appear to be responsible for the initiation of sexual differentiation. Early experiments by Jost (41) showed that removal of the gonad from male or female rabbit fetuses resulted in the female phenotype, which lent weight to the hypothesis that ovarian hormones are not critical in the development of the female phenotype, whereas testicular hormones are essential for the development of the male phenotype.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed2002

[Histamine receptors in the female reproductive system. Part I. Role of the mast cells and histamine in female reproductive system].

Histamine isolated from many different tissues, acts via three types of histamine receptors: H1, H2 and H3. In peripheral tissues histamine is mainly stored in mast cells (MC). Presence of mast cells was proved also in mammals' uteri. In human uterus the majority of mast cells are located close to smooth muscle cells. It might indicate that MC plays a role in tissue remodelling during the menstrual cycle. The quantity and activity of mast cells is in connection with hormonal status of the organism. Although there are some differences, human uterine mast cells are similar to the mast cells isolated from other tissues. It is suggested that histamine is important for normal ovulation, blastocyst implantation, placental blood flow regulation, lactation and contractile activity of uterus. Histamine may also play a role in pathological processes such as pre-eclampsia or preterm delivery. The participation of mast cells and histamine in blastocyst implantation is very controversial. In W/Wv mice (without mast cells) normal implantation was observed. It denies the main role of mast cells in this process but dos not exclude histamine action. In mice the major source of histamine are uterine epithelial cells during early pregnancy. The influence of cytokines on blastocyst implantation and the role of histamine in cytokines release from the uterine mast cells are also very unclear.

Animals↗
PubMed1978

[Prolactin and human reproduction].

Prolactin was isolated and identified as a separate pituitary hormone distinct from human growth hormone. Since that time a rapidly expanding literature has accumulated on the physiology of pituitary prolactin secretion in normal and pathologic conditions. Currently the physiology and pathophysiology of pituitary prolactin secretion are under intensive investigation. Development of sensitive, specific radioimmunoassay for prolactin and improved roentgenographic techniques have increased the diagnostic acumen for incipient pituitary microadenomas. Dynamic function tests of prolactin secretion have not helped to distinguish whether a patient has a microadenoma or not. The basal prolactin level is probably the most useful single investigation for diagnosis a pituitary tumour. If women with pituitary tumours have ovulation induced with bromocriptine therapy, then there is a considerable risk of rapid enlargement of the tumour with the development of serious visual field defects often during the last trimester. The precise level of the risk is not clear, but is probably not great. The introduction of bromocriptine has heralded a major change in the menagement of the hyperprolactinaemia-hypogonadism syndromes and resulted in safer and easier treatment of many cases of infertility, menstrual disorders and, to a lesser extent of impotence. At present, bromocriptine therapy is the treatment of choice for hyperprolactinaemia.

Adenoma↗
PubMed2006

Isolation of Listeria monocytogenes from buffaloes with reproductive disorders and its confirmation by polymerase chain reaction.

Listeria monocytogenes, a gram-positive, facultative intracellular pathogen was isolated from buffaloes with a history of reproductive disorders and polymerase chain reaction (PCR) analyses for the presence of virulence-associated genes were conducted. A total of 530 samples of faecal, nasal, vaginal swabs and blood samples from 135 buffaloes were screened. The prevalence of L. monocytogenes and other Listeria spp. was found to be 4.4 and 7.4%, respectively. All isolates were subjected to PCR for virulence-associated genes (prfA, plcA, hlyA, actA and iap) and to pathogenicity testing by the phosphatidylinositol phospholipase C (PI-PLC) assay and mice and chick-embryo inoculation. All L. monocytogenes isolates were hemolytic and positive for the hlyA gene. One L. monocytogenes isolate possessed all five virulence-associated genes and was also positive in the PI-PLC assay as well as in the in vivo pathogenicity tests. The remaining hemolytic L. monocytogenes isolates lacking the plcA gene and PI-PLC assay activity were, however, non-pathogenic via mice and chick-embryo inoculation tests, in spite of having the hlyA gene. The detection of multiple virulence-associated genes, in combination with in vitro pathogenicity tests, must be performed to identify pathogenic L. monocytogenes.

Animals↗
PubMed1996

Isolation of porcine respiratory coronavirus from pigs affected with porcine reproductive and respiratory syndrome.

Four cytopathogenic viruses were isolated in CPK cells derived from porcine kidneys from tonsils and lungs of 3 of 15 pigs affected with porcine reproductive and respiratory syndrome virus. Physicochemically and morphologically, the isolates were similar to a coronavirus. The isolates were not distinguished from transmissible gastroenteritis virus (TGEV) by a neutralization test using polyclonal antibodies, but differentiated from TGEV by monoclonal antibodies capable of discriminating between TGEV and porcine respiratory coronavirus (PRCV), indicating that the isolates were PRCV. In a serological survey of 30 serum samples each collected from about 50 days old pigs in the 2 affected farms, 29 (97%) and 15 (50%) sera were positive for neutralizing antibody against the isolate with the titers ranging from 2 to 64, respectively.

Animals↗
PubMed2006

Isolation of Lawsonia intracellularis in Korea and reproduction of proliferative enteropathy in pigs and hamsters.

Lawsonia intracellularis (L. intracellularis) was isolated from a Korean pig suffering acute proliferative enteropathy. In vitro culture conditions of L. intracellularis were established in McCoy cells. Pigs and hamsters experimentally infected with the pure culture of L. intracellularis reproduced clinical signs and intestinal lesions of proliferative enteropathy. The presence of L. intracellularis in the intestinal lesions was confirmed by immunohistochemistry with L. intracellularis-specific monoclonal antibodies.

Animals↗
PubMed1998

Molecular variation in the nucleoprotein gene (ORF7) of the porcine reproductive and respiratory syndrome virus (PRRSV).

The nucleoprotein gene (ORF7) of 15 European isolates of porcine reproductive and respiratory syndrome virus (PRRSV) was sequenced and compared with corresponding sequences of other PRRSV isolates (2 European and 13 American) and one isolate each of other arteriviruses (the lactate dehydrogenase elevating virus (LDV), the simian haemorrhagic fever virus (SHFV) and the equine arteritis virus (EAV)). Their phylogenetic relationships were established using neighbour-joining and parsimony methods. Four lineages (PRRSV, LDV, SHFV and EAV) were discriminated. Two genotypes of PRRSV, European and American, could be further identified. The European genotype of PRRSV was highly conserved. Analysis of the nucleotide and amino acid substitutions in PRRSV ORF7 revealed four stable regions, probably conserved because of their requirement for nucleocapsid function and/or structure. No constant mutations accumulation in the ORF7 could be determined precisely when either synonymous or non-synonymous mutations were studied. Passage of the European PRRSV in vivo had little influence on the ORF7 sequence: only a small number of synonymous substitutions in ORF7 was detectable, confirming its low variability.

Amino Acid Sequence↗
PubMed2004

Subpopulation characteristics of egg-contaminating Salmonella enterica serovar Enteritidis as defined by the lipopolysaccharide O chain.

Characterization of Salmonella enterica serovar Enteritidis was refined by incorporating new data from isolates obtained from avian sources, from the spleens of naturally infected mice, and from the United Kingdom into an existing lipopolysaccharide (LPS) O-chain compositional database. From least to greatest, the probability of avian isolates producing high-molecular-mass LPS O chain ranked as follows: pooled kidney, liver, and spleen; intestine; cecum; ovary and oviduct; albumen; yolk; and whole egg. Mouse isolates were most like avian intestinal samples, whereas United Kingdom isolates were most like those from the avian reproductive tract and egg. Non-reproductive tract organ isolates had significant loss of O chain. Isogenic isolates that varied in ability to make biofilm and to be orally invasive produced different O-chain structures at 25 degrees C but not at 37 degrees C. Hens infected at a 91:9 biofilm-positive/-negative colony phenotype ratio yielded only the negative phenotype from eggs. These results indicate that the environment within the hen applies stringent selection pressure on subpopulations of S. enterica serovar Enteritidis at certain points in the infection pathway that ends in egg contamination. The avian cecum, rather than the intestines, is the early interface between the environment and the host that supports emergence of subpopulation diversity. These results suggest that diet and other factors that alter cecal physiology should be investigated as a means to reduce egg contamination.

Animals↗
PubMed1985

Adverse effects of human leukocyte antigen-DR sharing on fertility: a cohort study in a human isolate.

To elucidate further the reproductive effects of human leukocyte antigen (HLA) sharing among spouses, we have been investigating prospectively the relationship between HLA-A, -B, and -DR sharing and reproductive outcome in the Hutterites, a religious isolate that proscribes contraception. For the first time the reproductive effects of HLA-DR sharing in a fertile population is reported in this article. Median intervals from marriage to first through fifth births were longer among couples who shared more than one HLA-A, -B, or -DR antigen. Longer intervals were associated with increased spontaneous abortion rates among couples who shared HLA-DR antigens (27%), compared with couples who shared only HLA-A or -B antigens (9%) and couples who shared no antigens (12%). Median completed family sizes were 5.0, 8.5, and 8.0 among the groups, respectively. However, some couples who shared HLA-DR antigens experienced no spontaneous abortions, despite ten or more pregnancies. Therefore, although HLA-DR compatibility, per se, is not deleterious, our data suggest a potentially important role for undefined HLA-linked genes in normal pregnancy.

Abortion, Spontaneous↗
PubMed2006

The impact of animal age, bacterial coinfection, and isolate pathogenicity on the shedding of porcine reproductive and respiratory syndrome virus in aerosols from experimentally infected pigs.

The objective of this study was to evaluate the role of different variables (animal age, bacterial coinfection, and isolate pathogenicity) on the shedding of Porcine reproductive and respiratory syndrome virus (PRRSV) in aerosols. Animals were grouped according to age (2 versus 6 mo) and inoculated with a PRRSV isolate of either low (MN-30100) or high (MN-184) pathogenicity. Selected animals in each group were also inoculated with Mycoplasma hyopneumoniae. The pigs were anesthetized and aerosol samples (1000 breaths/sample) collected on alternating days from 1 to 21 after PRRSV inoculation. The results indicated that animal age (P = 0.09), M. hyopneumoniae coinfection (P = 0.09), and PRRSV isolate pathogenicity (P = 0.15) did not significantly influence the concentration of PRRSV in aerosols. However, inoculation with the PRRSV MN-184 isolate significantly increased the probability of aerosol shedding (P = 0.00005; odds ratio = 3.22). Therefore, the shedding of PRRSV in aerosols may be isolate-dependent.

Age Factors↗
PubMed1994

Proteoglycans and hyaluronan in female reproductive organs.

Proteoglycans and hyaluronan have been isolated from various female reproductive organs and fetal membranes. Special attention has been directed to changes in the composition of these molecules in the tissue during pregnancy and ovulation. Various chondroitin sulfate/dermatan sulfate proteoglycans, which represent extracellular matrix proteoglycans, are closely related to the organization of connective tissues. Heparan sulfate proteoglycans are widely distributed on the plasma membrane of most mammalian cells including those in the female reproductive organs. They are involved in various aspects of cell-to-cell or cell-to-extracellular matrix interactions. Although the precise biological functions of these proteoglycans are not currently clear, recent advances in biochemistry and molecular biology techniques promise an exciting new development in this area.

Animals↗
PubMedDate not supplied

Isolation of infectious bronchitis virus from intestine and reproductive organs of laying hens with dropped egg production.

A total of 52 samples (22 cloacal swabs and 30 pooled ovaries and oviducts) from hens with a history of a 25 to 40% drop in egg production from 30 flocks were examined for the isolation of infectious bronchitis virus in embryonated chicken eggs. Five isolates were obtained: three from cloacal swabs and two from reproductive organs. These isolates were identified and characterized on the basis of agar-gel-precipitation, hemagglutination, and neutralization tests and other physicochemical characteristics.

Animals↗
PubMed2005

Identification and isolation of embryonic stem cells in reproductive endocrinology: theoretical protocols for conservation of human embryos derived from in vitro fertilization.

BACKGROUND: Embryonic stem cells (ESC) are pluripotent cells obtained from the inner cell mass (ICM) of blastocysts derived from in vitro culture associated with reproductive endocrinology therapy. Human ESCs are regarded as highly significant since they retain the capacity to differentiate into any of approximately 200 unique cell types. Human ESC research is controversial because to acquire such cells, the ICM of human blastocysts must be manipulated in a way that renders embryos nonviable and unsuitable for transfer in utero. Techniques to yield competent ESCs with conservation of source blastocysts would satisfy many objections against ESC research, but at present such approaches remain largely untested. RESULTS AND DISCUSSION: We contrast experimental culture of single blastomeres obtained by 1) non-destructive biopsy of embryos destined for transfer, and 2) isolation of karyotypically normal blastomeres from disaggregated ("dead") embryos considered unsuitable for transfer, and evaluate these approaches with regard to production of ESCs. Pluripotency was confirmed by morphological criteria and by quantification of divergent homeodomain proteins specific to undifferentiated cell development. Following ESC isolation and identification, assessment was conducted according to a novel ESC grading system, also proposed here. CONCLUSION: The role of reproductive endocrinology in ESC research remains paramount. In this report, we hypothesize new and expand on existing strategies having the potential to enhance human ESC isolation, identification and in vitro maintenance.

Animals↗
PubMed2000

Variations in the major envelope glycoprotein GP5 of Czech strains of porcine reproductive and respiratory syndrome virus.

The major envelope glycoprotein genes (ORF5) of seven Czech isolates of porcine reproductive and respiratory syndrome virus (PRRSV) were amplified and their nucleotide sequences were determined. ORF5 displayed nucleotide and amino acid identities of 87.5-100% and 87. 6-100%, respectively, among the isolates. In a phylogenetic tree, all European isolates were grouped in a genotype distinct from that of reference American strains (VR-2332, IAF-Klop). Among the European isolates, two different clades were identified. Two Czech isolates (V-501 and V-503) and Italian strain PRRSV 2156 fell into one clade. The remaining European strains comprised the second clade. Surprisingly, two separately clustered strains (V-501 and V-516) were isolated from the same herd. Additionally, the possible effect of in vitro cultivation on the nucleotide sequence was analysed. Nine point mutations in the ORF5 region resulted from 152 in vitro passages of the V-502 isolate in MARC-145 cells.

Amino Acid Sequence↗
PubMedDate not supplied

[Spectrum of microflora isolated from various areas of the female reproductive tract].

The composition of microflora in different sections of the reproductive tract of women with disturbances of reproductive function was studied. The study revealed that the spectrum of microorganisms isolated from a bioptic specimen taken from the cavity of the small pelvis was narrower in comparison with such spectrum in material aspirated from the uterine cavity. The latter was narrower in comparison with that in the microflora of the lower sections of the reproductive tract. The possibility for one and the same patient to have both similarities and essential differences in the spectra of microflora in different sections of the reproductive tract was shown.

Adult↗
PubMed1990

Infectivity of Trichinella pseudospiralis isolated from carrion.

The reproductive capacity index for Trichinella pseudospiralis infective larvae was similar for worms isolated from mouse carcasses on the day upon which mice were killed (day 0: 104.4 +/- 18.6 [mean +/- SD]) and on day 5 following mouse death (106.1 +/- 23.6), but was reduced for worms recovered from carcasses on day 10 postkill (PK: 22.7 +/- 5.7). Larvae isolated from mouse carcasses held at 24 C after day 10 PK were not infective. The percentage of viable worms (tightly coiled or moving) isolated from carrion was similar on days 0 and 5 PK but had declined to 40.4% by day 10 PK and showed a further reduction to 11.8% for worms isolated from carrion on day 15 PK. Viable worms were not recovered from carcasses after day 15 PK.

Animals↗
PubMed2007

Influence of isolate pathogenicity on the aerosol transmission of Porcine reproductive and respiratory syndrome virus.

The objectives of this study were to evaluate the role of isolate pathogenicity in the aerosol transmission of Porcine reproductive and respiratory syndrome virus (PRRSV) and to determine whether PRRSV could be detected in air samples. To assess transmission, we exposed naive recipient pigs to aerosols from pigs inoculated with PRRSV MN-30100, an isolate of low pathogenicity, or MN-184, a highly pathogenic isolate. Blood samples and nasal-swab samples were collected from the inoculated pigs during the exposure period and tested for the presence of PRRSV RNA by quantitative (real-time) reverse-transcriptase polymerase chain reaction (RT-PCR); the amount of RNA was expressed as the median tissue culture dose per milliliter (TCID50/mL). The recipient pigs were clinically evaluated for 14 d after exposure and tested on days 7 and 14 by qualitative RT-PCR and enzyme-linked immunosorbent assay (ELISA). To prove the presence of PRRSV in aerosols, air samples were collected from each recipient-pig chamber by means of an air sampler. The PRRSV RNA concentrations were significantly higher (P = 0.01) in the blood samples from the pigs infected with PRRSV MN-184 than in the blood samples from those infected with PRRSV MN-30100; however, the concentrations in the nasal-swab samples were not significantly different (P = 0.26). Recipient pigs exposed to aerosols from pigs infected with PRRSV MN-184 became infected, whereas those exposed to aerosols from pigs infected with PRRSV MN-30100 did not; the difference in transmission rate was significant at P = 0.04. We detected PRRSV MN-184 RNA but not PRRSV MN-30100 RNA in air samples by PCR. Under the conditions of this study, PRRSV isolate pathogenicity may influence aerosol transmission of the virus.

Aerosols↗