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PubMed1994

Persistence of porcine reproductive and respiratory syndrome virus infection in a swine operation.

A herd of Quebec seedstock pigs experienced in early 1992 a typical outbreak of porcine reproductive and respiratory syndrome (PRRS) associated with lesions of interstitial, proliferative and necrotizing pneumonia in weaned piglets. The nature of the infection was confirmed by serology using indirect immunofluorescence (IIF) and virus isolation in primary cultures of porcine alveolar macrophages (PAM). Farm production recovered after eight weeks of losses. In order to evaluate the persistence of infection in the herd, five SPF-piglets were introduced in two different sections of the PRRS-affected barn four months after the disappearance of clinical symptoms, and two others were placed in a neighboring building with apparently healthy farrow-to-finnish pigs. Clinical signs, body temperature, humoral immune response, virological and histopathological findings were recorded over a 42-day period. Clinical signs were evident in all of the sentinels and prolonged fever (> or = 40 degrees C) was recorded one day post-exposure (PE). Antibody titers to PRRS virus could be detected by IIF on PAM seven days PE, and reached 1:1024 by day 21 PE. Three of the sentinels developed significant virus neutralizing antibody titers (> 1:8 to < or = 1:128) by day 35 PE. In all cases, the virus could be isolated from the serum between day 7 and 42 PE. Thus, the virus and specific antibodies coexisted for several weeks. Lesions of interstitial pneumonia was demonstrated in few animals. In experimental inoculation studies, the viral strain isolated from the sentinel pigs produced severe reproductive disorders in two sows inoculated at 95 days of gestation.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed2004

Tissue perfusion essential for spermatogenesis and outcome of testicular sperm extraction (TESE) for assisted reproduction.

PURPOSE: In order to determine if there are areas of major and minor perfusion in a single testicle and if the quality of sperm is correlated with quantity of perfusion we collected testicle tissue for TESE in accordance to the local testicle tissue perfusion. METHODS: A patient undergoing TESE underwent testicular perfusion mapping using contrast enhanced ultrasound. The exposed tissue was scanned with a Laser Doppler scanner and perfusion rates were determined measuring tissue perfusion units (TPUs). Tissue was biopsied and sperm were selected and prepared for assisted reproduction. RESULTS: The total amount of isolated sperm correlated highly with the intensity of tissue perfusion showing high number of sperm in areas with high TPUs. CONCLUSIONS: This is the first demonstration that sperm quality and quantity is depending on tissue perfusion within the testicle. To further improve infertility treatment we propose that random biopsies could be replaced by perfusion-dependent collection of testicular tissue.

Biopsy↗
PubMed1997

Indirect fluorescent IgM antibody response of pigs infected with porcine reproductive and respiratory syndrome syndrome virus.

IgG and IgM antibody responses were examined by an indirect fluorescent antibody method in pigs following inoculation with different porcine reproductive and respiratory syndrome virus (PRRSV) isolates or a vaccine virus. Viremia was also examined in the pigs. The IgG antibody was first detected between 9 and 14 days post inoculation (PI) and maintained high titers for at least 7 weeks PI. No change in IgG antibody titers was observed when the pigs were reinoculated with PRRSV 35 days PI. IgM antibody was detected between 5 and 28 days PI in the pigs. Reinoculation at 35 days PI caused a short term rise of IgM antibody. Virus was isolated from sera collected between 2 and 21 days PI. The IgM antibody was detected regularly in sera collected during viremia and up to 1-2 weeks after the viremic periods. These results suggest that pigs with detectable IgM antibody are probably pigs with recent infection and that routine testing of IgM antibody in purchased breeding pigs from seropositive farms may be useful in identification of pigs with recent infection.

Animals↗
PubMed1985

Localization of the antigotensin-converting enzyme activity in testis and epididymis.

Angiotensin-converting enzyme (ACE) has been studied in different reproductive organs of the male rat, in somatic cell lines clonally derived from both rat and mouse testes, and in isolated spermatogenic cells of the mouse. Among the various reproductive organs only testis and epididymis show high levels of enzyme activity. The testicular activity is found mainly in the isolated germinal cells and residual bodies, whereas somatic cell lines contain negligible levels of activity even after addition of hormones and growth factors. Testicular homogenates, spermatogenic cells, epididymal spermatozoa, and spermatozoan cytoplasmic droplets, when fractionated by anion exchange chromatography, contain one major and one minor activity peak, whereas epididymal homogenates and epididymal secretions reveal an additional major activity peak together with the minor peak. All forms of ACE have a similar response to different modifiers, and are equally sensitive to the specific inhibitor N-[(S)-1-(ethoxycarbonyl)-3-phenylpropyl]-L-alanyl-L-proline (Enalapril). The testicular enzyme could provide a useful marker for spermatogenic maturation and/or cytoplasmic processes both in testis and epididymis. The separate epididymal peak is a secretory enzyme that may be responsible for the processing of spermatozoan plasma membrane constituents during epididymal transit, or may have a role in attacking some biologically active compounds.

Animals↗
PubMed1996

Expression of alternate growth hormone receptor messenger RNA in ovary and uterus of cattle.

Growth hormone (GH) receptor mRNA is found within the corpus luteum and endometrium of cattle. However, binding sites for placental lactogen (PL) but not GH are found within these tissues. The objectives were to isolate cDNA for the GH receptor within the reproductive tissues of cattle and to examine these cDNA as potential variants of the GH receptor that bind PL. Ten cDNA clones were isolated from a bovine endometrial cDNA library with a 32P-labeled cDNA of the GH receptor extracellular domain. On the basis of restriction enzyme digestion, 2 of the 10 cDNA clones contained exon 1. The DNA sequence of these clones was determined by dideoxy nucleotide sequencing. The exon 1 DNA sequence of each clone (exon 1B) was different from the previously reported exon 1 for the bovine GH receptor cDNA isolated from liver (exon 1A). Analyses of these cDNA sequences showed that exon 1B contained significant homology with placental forms of the GH receptor found in mouse and human. Unlike the human cDNA, the bovine cDNA isolated from endometrium contained an intact third exon. Amplification of GH receptor mRNA by reverse transcriptase polymerase chain reaction, with exon 1A- and 1B-specific forward primers, showed that exon 1B was expressed in liver, corpus luteum, ovary, endometrium, and myometrium. Exon 1A was found almost exclusively in liver, and little was found in reproductive tissues. The predicted initiation of protein coding for the GH receptor was within the second exon and was not changed by the splicing of the alternate first exon. This suggests that the alternate mRNA results in the expression of intact GH receptor protein that is similar to that found within liver. Alternative promoters (1B) may control the expression of the receptor outside the liver. Furthermore, mechanisms other than the differential splicing of GH receptor protein may dictate the specificity of PL binding within the endometrium and corpus luteum.

Animals↗
PubMed2003

Electron microscopic study of in vitro cultures of Hammondia heydorni (Berlin 1996) tachyzoites after passages through dogs, mice, rats, guinea pigs and jirds.

This study describes the fine structure and reproduction of tachyzoites of Hammondia heydorni (isolate Berlin 1996) after in vitro cultivation of stages isolated from serial passages between dogs and various intermediate hosts such as mice, rats, guinea pigs, jirds, knock-out mice, goats and sheep. The tachyzoites are identical with respect to their ultrastructural features to the corresponding stages of the NC-1-strain of Neospora caninum. This fact conforms with other already published data and underlines our opinion that the recently redescribed N. caninum Dubey et al. 2002 is a synonym of the previously described H. heydorni (Tadros and Laarman 1976) Dubey 1977.

Animals↗
PubMed1984

[Studies on biological characteristics of enterovirus type 70 (EV 70)].

Enterovirus type 70 (EV 70) is a new type of enterovirus, which is a causative agent of "Acute Hemorrhagic Conjunctivitis" (AHC). It appeared for the first time in Ghana in 1969, and occurred in Japan in 1971. The optimal temperature for growth of EV 70 is 33-35 degrees C, and lower than that of other enteroviruses. Ninety two isolates of EV 70 were investigated to know the biological characteristics. Isolates were obtained in Japan and foreign countries in Africa, Asia and Europe in 1971-1981, and contained eighty seven from eye swabs, three from feces and two from throat swabs. Reproductive capacity of EV 70 at 38 degrees C varied from one isolate to the other. The ratios in log of 33 degrees C yield to 38 degrees C yield ranged from 0.2 to 3.2, and showed no tendency to obtain reproductive capacity at high temperature chronologically after invasion to Japan. In order to find whether EV 70 obtains the reproductive capacity at 38 degrees C, three isolates, which had high pfu ratios (33 degrees C/38 degrees C, log), 2.6-3.2, were subjected to 5 passages by plaquing method. It was found that they obtained the capacities remarkably, and the ratios decreased to -0.5-0.6. As EV 70 exhibits a physicochemical characteristic of enteroviruses, the reproductive capacity in organ cultures of human fetal small intestine was investigated. The results indicated that EV 70 isolates grew distinctly, though the degree of that was less in comparison with coxsackievirus B1 and echovirus 11, and that they increased in the capacities by passages in the intestine. These findings suggested that EV 70 developed the reproductive capacities at high temperature and that in human intestine experimentally. By neutralization tests using two kinds of antisera against EV 70, it was found that serological characteristics of EV 70 changed after invasion to Japan. Intratypic antigenic mutants were first isolated in some parts of Honshu areas in 1972, and took the place of prototype-like isolates throughout Japan in the following one or two years, and after that, no prototype-like isolates obtained anywhere. The same trend was observed in isolates in foreign countries. To investigate differences and changes of these biological characteristics of EV 70 more precisely, further observations seemed to be necessary.

Enterovirus↗
PubMed1987

Differentiation of poliovirus type I isolates in the 1982 epidemic from Sabin-I strain by antigenic and temperature markers.

Poliovirus type 1 strains recovered from patients with poliomyelitis during the epidemic of 1982, were distinct antigenically from Sabin-1 strain by comparing homologous and heterologous neutralization rate constants of Sabin-1 specific antiserum. With the reproductive capacity at 40 degrees C, these isolates could be easily differentiated from vaccine strain. It was suggested that the epidemic of poliomyelitis in 1982 was not caused by vaccine strain. The 24 isolates reacted with LSc and/or Sabin-1 antisera to the same extent. It was speculated that they might be antigenically similar if not identical. Three isolates which were collected from the later part of epidemic formed small plaques at 40 degrees C. Rabbit antisera against poliovirus strains 3844, Sabin-1, Mahoney and Brunhilde were produced. Antigenic relatedness among the strains was tested by kinetic neutralization. The strain 3844 was distinct from Brunhilde, Mahoney and Sabin-1. Asymmetric cross-reactions between Mahoney and Sabin-1 strains were clearly demonstrated.

Antigens, Viral↗
PubMed1980

Aerobic and anaerobic urethral flora of healthy females in various physiological age groups and of females with urinary tract infections.

We characterized the aerobic and anaerobic urethral flora of healthy females in three physiological age groups (premenarcheal, reproductive, and postmenopausal) and of females with urinary tract infections. The mean number of species per sample was 6.5, 7.7, and 10.3 for each of the physiological age groups, respectively, and 6.5 for the urinary tract infection group. Marked quantitative changes were seen with age and disease. Aerobes accounted for 65.6 and 73.8% of the flora of the premenarcheal and reproductive age groups, respectively, whereas anaerobes were dominant in the postmenopausal age group, accounting for 65.5% of the flora. Aerobic gram-negative rods were not isolated from any of the premenarcheal or reproductive-age subjects. Of the 10 postmenopausal subjects, 5 carried aerobic gram-negative rods, but these organisms accounted for only 1% of the flora. In contrast, they constituted 95% of the urethral flora of the urinary tract infection group. Bacteroides melaninogeneicus was commonly isolated and was the dominant isolate in the postmenopausal age group. Bacteroides fragilis was recovered from 7 of the 10 postmenopausal subjects, but these organisms constituted only 3% of the total flora. The factors responsible for the changes in urethral flora with age remain to be determined.

Adolescent↗
PubMed2004

Variation in the structure of Toxoplasma gondii and the roles of selfing, drift, and epistatic selection in maintaining linkage disequilibria.

Previous studies of Toxoplasma gondii, based on samples dominated by clinical isolates, have concluded that its population structure is clonal, despite the sexual reproduction that occurs in cats. To determine whether this applies to non-clinical isolates, we compared patterns of linkage disequilibrium (LD) among seven loci in samples of T. gondii from Brazil and the US. LD was detected in both locations, but it was substantially lower in Brazil. The lower LD in Brazil can be explained by a higher rate of sexual reproduction between different genotypes (outcrossing) because of a higher rate of transmission. The extent of LD between pairs of physically unlinked loci varied significantly in each location. Moreover, the magnitude of LD between corresponding locus pairs in Brazil and the US was correlated, despite minimal gene exchange between the continents (mean FST = 0.19). The heterogeneity among locus pairs and the correlation in LD between physically unlinked locus pairs from different continents suggests that locus-specific factors, such as epistatic selection are involved in maintaining LD in T. gondii. Possibly, the unique life cycle of T. gondii with its unpredictable transmission among diverse host species and distinct ecological habitats requires specific combinations of alleles from multiple loci. The usefulness of typing isolates based on physically unlinked loci is questioned not only by the geographic variation in the reproductive population structure, but mainly by the low overall predictability of the genotype of one locus based on the genotype in another (unlinked) locus. This predictability ranged between 23 and 45%, but was close to nil for a considerable fraction of locus pairs.

Alleles↗
PubMed1988

Interaction of surgical deafening and photoperiod on cloacal gland and testes size in Japanese quail.

Two experiments were conducted to further examine the interaction of social stimuli and photoperiod on cloacal and gonadal responses in male Japanese quail. In experiment 1, adult males kept on a maximal (15L:9D) stimulatory photoperiod were surgically deafened and/or visually isolated from roommates. After 6 weeks, there were no differences in cloacal gland or testes size among visually isolated birds, deafened birds, visually isolated and deafened birds, and control birds. It would appear that neither auditory nor visual contact with other males is necessary to maintain reproductive activity under a maximal stimulatory photoperiod. In Experiment 2, 5-week-old males were surgically deafened and kept on either a maximal (15L:9D) or minimal (12L:12D) stimulatory photoperiod for about 10 weeks. The rates of cloacal gland growth were significantly slower in birds kept on the shorter photoperiod compared to the longer photoperiod and in deafened quail compared to intact quail. The difference in cloacal gland size between deafened and intact birds was markedly greater on the minimal compared to the maximal stimulatory photoperiod. These findings suggest that under a minimal stimulatory photoperiod auditory information supplements the photoperiod to accelerate reproductive maturation. At a maximal stimulatory photoperiod, however, the effects of auditory cues on cloacal gland growth appear masked.

Acoustic Stimulation↗
PubMed1982

The characterisation and pathogenicity of porcine enteroviruses isolated in Victoria.

Approximately 23 viruses were isolated from healthy pigs, pigs with encephalitis, and in cases of reproductive failure. Five viruses were identified as enteroviruses and a total of 10 isolates were shown to cross-react serologically to varying degrees. Twenty viruses were neutralised by a reference antiserum of serotype 8 porcine enterovirus. Intracerebral inoculaton of colostrum-deprived piglets with 2 of the characterised viruses caused lesions of encephalomyelitis which were not induced by oral infection. Intrafoetal inoculation of 2 sows with one characterised faecal isolate caused foetal death and abortion, but no adverse effects followed oral dosage.

Abortion, Veterinary↗
PubMed1999

Porcine reproductive and respiratory syndrome virus and Haemophilus parasuis antigen distribution in dually infected pigs.

Immunohistochemical, viral and bacterial isolation techniques were used to study the distribution and localization of porcine reproductive and respiratory syndrome virus (PRRSV) and Haemophilus (H.) parasuis in experimentally infected pigs. Thirty pigs seronegative to PRRSV and H. parasuis were divided into four groups. Group A pigs (10 animals) were inoculated with both virus and bacteria; group B pigs (10 animals) were inoculated with bacteria, group C pigs (five animals) were inoculated with virus and group D pigs (five animals) were kept as negative controls. All pigs of groups A and C became infected with PRRSV, according to virological techniques used (immunohistochemistry, virus isolation and virus serology). Lung, heart and tonsils were the most frequently immunolabeled tissues, and monocyte/macrophage lineage cells were the target for PRRSV in all tissues. All pigs in groups A and B also became infected with H. parasuis based on immunohistochemical and bacterial isolation results. Serosal surfaces, lung and tonsils were the most frequently immunolabeled tissues, and bacteria were found in monocyte/macrophage lineage cells as well as within neutrophil cytoplasm. No differences in terms of bacterial distribution or localization in tissues of pigs of groups A and B were detected. These results suggest that there is no influence of the previous infection with PRRSV in the occurrence of H. parasuis infection.

Animals↗
PubMed2005

Lactobacillus species isolated from the vagina: identification, hydrogen peroxide production and nonoxynol-9 resistance.

BACKGROUND: Lactic acid production is considered to be the major protection mechanism of lactobacilli against vaginal infections due to genital pathogens. Some species of Lactobacillus are also hydrogen peroxide (H(2)O(2)) producers. Nonoxynol-9 (N-9) is a nonionic detergent and is the active component of many spermicidal preparations. It immobilizes sperm by disrupting the cell membrane and is believed to act similarly on a number of bacteria and viruses. It is known that N-9 inhibits Lactobacilli in vitro at concentrations of 0.1% to 1%. PURPOSE: The present study was conducted to identify the species of Lactobacillus isolated from vaginal fluids of reproductive-age women and to characterize the H(2)O(2)-producing and N-9-resistant strains in an Argentine population. RESULTS: We identified Lactobacillus acidophilus, L. fermentum, L. gasseri, L. jensenii, L. casei subsp. casei, L. brevis and L. delbrueckii subsp. delbrueckii as the most frequent species. In this Argentine, South American population, 62% of women had H(2)O(2)-producing vaginal lactobacilli. We found a high number of sensitive strains. Sixty-two H(2)O(2)-producer strains were detected, 50 (80.6%) strains were sensitive to N-9 and 12 (19.4%) strains were resistant to the inhibitory effect of N-9. DISCUSSION: The vaginal microecologic findings are comparable to those found in other populations and suggest that (1) vaginal microecologic conditions are likely to be similar among Argentine women as in other countries, and (2) N-9 may have deleterious effects as in other populations.

Adult↗
PubMed1989

Dynamic behavioural models and contraceptive choice.

Dynamic models of contraceptive use fill a theoretical gap. They bring behavioural content to the mathematically elegant Markov models of family building. They meet the criterion that Bulatao (1989) advances that method use, discontinuation and switching be considered not in isolation, but with reference to individual reproductive goals. Dynamic models help to link the literature on method choice with the literature on method effectiveness. These theoretical advantages are, at present, counter-balanced by empirical limitations. This article explores the theoretical and empirical underpinnings of dynamic contraceptive choice models.

Abortion, Legal↗
PubMed2001

Assessing non-metric skeleton characters as a morphological tool.

The appearance of non-metric skeletal characters in vertebrates results mainly from basic genetic control, as proved and documented for house mice and humans. Although the heritability of non-metric traits, mainly the presence of foramina and similar structures for blood vessels and nerves or dental occlusal variants, have been evaluated as rather low, the simultaneous consideration of several traits allows estimation of epigenetic variation in time and space as a result of genetic relationship. Thus, the main use of non-metric characters has been aimed at assessing epigenetic variability and divergence among populations. Applications extend from the problem of genetic isolation of populations, the lack of reproductive contact, detection of genetic drift, systematic studies to clarify species taxonomy, to phylogenetic interpretation. Additionally, non-directional deviations from bilateral symmetry in non-metric characters, e.g. fluctuating asymmetry, could be caused by current environmental conditions in general. Fluctuating asymmetry is regarded as a measure of developmental instability to indicate the presence of genomic changes or the influence of contamination and/or habitat deterioration, and is also used as a further population parameter with integrated information. However, standpoints on the use of fluctuating asymmetry are quite inconsistent, fluctuating themselves between considering it a powerful biomonitoring tool to being merely a curious scientific toy.

Journal Article↗
PubMed2003

Does leptin mediate the effect of photoperiod on immune function in mice?

Seasonal fluctuations in immune status have been documented for avian and mammalian populations. During the late summer and early fall, immune function is bolstered to help animals cope with the more physiologically demanding winter. The environmental cue for these seasonal changes is apparently decreasing photoperiod. In the present study, we determined the potential role of leptin in mediating the effect of photoperiod on cell-mediated immune responses in male mice. Leptin-deficient (ob/ob) and littermate control mice were housed for 10 wk in either a short (8L:16D) or a long (16L:8D) photoperiod beginning at 6 wk of age. After the mice were killed, immune and reproductive organs were weighed and splenocytes isolated. The proliferative and cytokine responses (interleukin [IL]-2 and IL-4) of splenocytes to the T-cell mitogen, concanavalin A (Con A; 0-40 microg/ml), were determined. Body weights were elevated and both testes and seminal vesicle weights subnormal in ob/ob mice (by ANOVA, main effect of leptin deficiency), but thymuses and spleens were of normal size. Serum leptin levels were at minimum detection limits in ob/ob mice, but leptin levels in control mice housed at 8L:16D were higher than in control mice housed at 16L:8D. The proliferative response of splenocytes from ob/ob mice to Con A was subnormal (by ANOVA, main effect of leptin deficiency), but photoperiod had no effect on this response. Production of IL-2 in splenocytes of ob/ob mice was subnormal (by ANOVA, main effect of leptin deficiency) irrespective of photoperiod, but cells from mice housed at 8L:16D (by ANOVA, main effect of photoperiod) produced more IL-2 than cells from animals housed at 16L:8D. In contrast, a leptin deficiency did not alter IL-4 production, but cells from animals (ob/ob and controls) housed at 16L:8D produced less IL-4 than cells from animals housed at 8L:16D (by ANOVA, main effect of photoperiod). The present study suggests that both photoperiod and leptin have mutually independent effects on the proliferation of lymphocytes and cytokine production profiles. The data do not provide definitive support for the hypothesis that photoperiod-induced changes in leptin secretion mediate the effects of season on immune status.

Animals↗