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PubMedDate not supplied

[Characteristics of epidemiological strains of influenza A virus (H3N2) isolate in 1997-1999. Virus A/Moscow/10/99--a candidate to become the vaccine strain].

Antigenic properties of influenza A(H3N2) viruses isolated during two epidemic seasons 1997-98 and 1998-99 in Russia are analyzed. All strains are antigenic variants of the reference strain A/Sydney/5/97. Characteristics of epidemic strain A/Moscow/10/99, proposed by WHO expert committee as vaccine strain for 1999-2000 have been studied. This strain, isolated on chick embryos, is characterized by high reproductive activity in chicken embryos with an infectious titer of 10(6) EID50/0.2 ml, easily adapts to MDCK culture, and has a thermostable hemagglutinin.

Animals↗
PubMed2001

Vaginal carriage of group B Streptococcus in infertile women.

From May, 1999 to April, 2000, 256 high vaginal swabs were culture from asymptomatic infertile women attending the out-patient department of the Institute of Reproductive Medicine. 41 strains of Streptococcus agalactiae were isolated from 33 patients (12.89%). Five patients had repeated isolations even after adequate therapy.

Adult↗
PubMed1986

Polyploidization of aortic smooth muscle cells from hypertensive and genetically related normotensive rats.

Abnormalities of growth regulation in arterial smooth muscle cells (SMC) are important in the pathogenesis of vascular disease. Recent studies have demonstrated an accumulation of polyploid SMC in hypertensive, and to a lesser extent in normotensive, arteries. The aim of this study was to evaluate the intrinsic genetic predisposition of aortic SMC from spontaneously hypertensive rats (SHR) to become polyploid in response to in vitro growth stimulation. Flow cytometry revealed that in vitro polyploidization was greatest in Wistar-Kyoto rats (WKY, normotensive inbred rats genetically related to SHR), intermediate but high in SHR and lowest in outbred (Sprague-Dawley) and genetically unrelated inbred (Fischer) rats (P less than 0.001). No differences were observed between neonatal and adult animals of the same strain; non-arterial WKY cells remained diploid. Reproductive clonal populations of polyploid SMC could be isolated from early-passage cultures of SHR and WKY cells. These studies suggest intrinsic differences in in vitro polyploidization among different rat strains, and may improve understanding of SMC growth control.

Animals↗
PubMed2026

[Genes determining virulence factors of Escherichia coli strains isolated from prostate secretions patients with chronic bacterial prostatitis].

UNLABELLED: The aim of the work is to characterize virulence genes of E. coli strains isolated from prostate secretions patients with chronic bacterial prostatitis. MATERIALS AND METHODS: Escherichia coli were isolated from the prostate secretions of men of reproductive age (20-45 years) with chronic bacterial prostatitis using a generally accepted bacteriological method, the type was determined using MALDI-TOF mass spectrometry, virulence genes were PCR and sequencing. RESULTS: The genomes of the studied strains contain genes encoding groups of virulence factors: adhesins, toxins, capsule antigens, siderophores, invasins, and anti-immunity of the macroorganism. Itwas shown that the genes of adhesins, siderophores, and immune system counteraction factors prevailed in E. coli. CONCLUSION: Further studies of E. coli strains using genome-wide sequencing and proteomics technologies are needed. The accumulation of the obtained data will make it possible to use virulence genes as diagnostic markers in patients with chronic prostatitis, indicating the presence of infection.

Humans↗
PubMed1983

Comparative studies on influenza B virus. II. The effect of host cells on biological properties and polypeptide composition.

The reproduction patterns of various influenza B virus strains isolated in 1970-1976 using roller cultures of MDCK cells and chick embryos (CE) were compared. The cultural and allantoic virus populations did not differ in their sensitivity to non-specific inhibitors from mammalian sera and in their reactivity with specific haemagglutinins (HA). The content of infectious virus and HA in the harvested allantoic fluids as compared to medium fluids were 94- and 8-fold higher, respectively, even though the fluids did not differ in the titres of complement-fixing (CF) antigen. The mol. weight (MW) of HA1 polypeptide of the B/Len/75 virus prepared in culture was higher than that Of the allantoic virus (57.5 K and 55.5 K, respectively). Under reducing conditions, the HA of the virus from culture was represented mostly by the uncleaved HA0 polypeptide, while that of the allantoic virus by the HA1 and HA2 subunits. Under non-reducing conditions, the virus from medium fluid was found to contain glycopeptide D with MW of 90 K.

Animals↗
PubMed2003

Effectiveness of peptone-yeast extract (P-Y) medium in the cultivation and isolation of Entamoeba histolytica/Entamoeba dispar in Turkish patients.

Amebiasis is a common protozoan infection worldwide, causing serious health problems in both children and adults. Today, almost 10% of the world population is infected with Entamoeba histolytica/Entamoeba dispar. The aims of this study were both the comparison of the reproduction rates and densities of E. histolytica/E. dispar in Robinson, Dobell-Laidlaw and P-Y culture media and isolation of E. histolytica/E. dispar from stool samples in Peptone-Yeast (P-Y) medium. Trophozoites and cysts of E. histolytica/E. dispar, maintained in Robinson medium, and stool samples of patients with amebiasis were inoculated into P-Y, Robinson and Dobell-Laidlaw culture media. Reproduction rates reached their peak levels 48 h after the inoculation in all culture media. Reproduction rates in P-Y and Robinson media were found similar; however, they were higher than the reproduction rate in Dobell-Laidlaw medium (p < 0.01); there was no statistically significant difference between the reproduction rates of P-Y and Robinson media (p > 0.05). Twelve isolates from 12 patients were cultivated in P-Y medium and checked for reproduction everyday for 7 days. Twelve of the 12 (100%) isolates were cultivated in P-Y medium, indicating that the P-Y was an effective medium for the isolation of E. histolytica/E. dispar in stool samples. According to these results, P-Y medium could be preferred in immunologic, serologic and molecular studies and, thus the definitive diagnosis of amebiasis due to its low cost and simple formula.

Animals↗
PubMed2004

Mammary ECM composition and function are altered by reproductive state.

To address whether reproductive state alters mammary gland extracellular matrix (ECM) composition and function, ECM was isolated from nulliparous, pregnant, lactating, involuting, and regressed rat mammary glands. The ECM composition of fibronectin, tenascin, laminin, clusterin, and MMPs was found to vary dramatically with reproductive state. In 3-dimensional (3-D) culture, we identified novel effects of these endogenous mammary matrices on mammary epithelial cells. Specifically we found that (1) matrix isolated from nulliparous animals promoted the formation of epithelial ducts with bifurcation, (2) matrix isolated from mid-involuting mammary glands induced cell death, (3) matrix isolated from late-stage involuting glands restored glandular development, while (4) matrix isolated from parous animals restricted glandular morphogenesis. Our data were consistent with mammary gland ECM facilitating epithelial cell proliferation, differentiation, death, and glandular reorganization that occur during the pregnancy and involution cycle. Further, we show that the parous gland has persistent changes in ECM function. Cumulatively, our data demonstrated that the microenvironment of the normal adult mammary gland is highly plastic, which has important implications for mammary tumor cell progression and dormancy. These data also raised the possibility of targeting mammary matrix production with preventive or therapeutic interventions.

Animals↗
PubMed1997

Failure to establish chronic infection of the reproductive tract of the male horse with a South African asinine strain of equine arteritis virus (EAV).

Eight sexually mature horse stallions were inoculated intranasally with a South African asinine strain of EAV, a strain that was isolated from the semen of a donkey carrier. All horses developed fever, with maximum rectal temperatures of 38.9-39.9 degrees C recorded 3-6 d post challenge. Six horses showed very mild clinical signs of equine viral arteritis and two were asymptomatic. The virus was recovered from the nasopharynxes of six horses 2-7 d after inoculation, and from buffy-coat samples of all horses, 2-11 d after inoculation. Seroconversion to EAV was detected on days 8 and 10 and peak serum-virus-neutralizing antibody titres ranging from log10 1.2-1.8, on days 14-20 after challenge. The titres varied from log10 0.9-1.2 after about 10 weeks, when the experiment was terminated. In three stallions euthanased on days 5, 7 and 9 after challenge, virus was detected inconsistently in different parts of the reproductive tract and urine. No virus was isolated from the tissues of the reproductive tract collected from stallions on days 16, 23 and 68 after challenge. Five stallions were bred to six seronegative mares between 13 and 34 d post challenge. No clinical signs of EAV were observed, and neither was seroconversion detected in any of the mares after mating. No virus was recovered from semen samples collected at the time of breeding. The results of this study demonstrated that the tissues of the reproductive tracts of the stallions did not become persistently infected with a South African asinine strain of EAV.

Animals↗
PubMed2005

D-aspartate and reproductive activity in sheep.

D-aspartic acid (D-Asp) has been isolated from neuroendocrine tissues of many invertebrates and vertebrates. Recently, it has been demonstrated that this D-amino acid may be converted to N-methyl-D-aspartic acid (NMDA), a neuromodulator associated with sexual activity. In this study, we determined D-Asp and NMDA concentrations in endocrine glands and other tissues in ewes after D-Asp administration and in controls. We also evaluated the effects of d-Asp administration on the reproductive activity of ewes by determining either progesterone concentrations or LH pulses in the presence or absence of estradiol benzoate. The pineal gland showed the highest natural content of D-Asp (1.47+/-0.22 micromol/g tissue), whereas the pituitary gland had the highest capability to store d-Asp, with a peak value (9.7+/-0.81 micromol/g tissue) 6 h after its administration. NMDA increased sharply 12 h following D-Asp administration, reaching values three times higher than the baseline in both the pituitary and brain. D-Asp was quickly adsorbed after subcutaneous administration, with a peak in plasma levels 2 h after administration and a return to baseline values after 6 h. D-Asp administration achieved a significant (P < 0.001) increase in LH values with respect to estradiol or estradiol + D-Asp treatments. d-Asp treatment once or twice a week did not successfully drive acyclic ewes into reproductive activity. In conclusion, the results obtained in this study demonstrated that D-Asp is endogenously present in sheep tissues and electively stored in endocrine glands and brain after its administration. NMDA and LH increase following D-Asp administration suggesting a role of this D-amino acid in the reproductive activity of sheep.

Animals↗
PubMed2004

Failure to establish infection with Tetratrichomonas sp. in the reproductive tracts of heifers and bulls.

Experimental infection of the reproductive tracts of heifers and bulls with Tetratrichomonas sp. isolated from preputial smegma of virgin bulls was attempted. Nine heifers and four bulls were challenged by inoculation of 7 x 10(6) Tetratrichomonas sp. into the vaginal lumen and preputial cavity, respectively. Vaginal mucus and preputial smegma samples were collected and cultured for Tetratrichomonas sp. Heifers were slaughtered in groups of three at 2, 9 and 21 days after inoculation. Two heifers and two bulls infected with Tritrichomonas foetus and two uninfected heifers were used as controls for the model infection. Tetratrichomonas sp. were only isolated in vaginal mucus of 7/9 inoculated heifers at 6h post-inoculation, and genital secretions taken at slaughter time from vagina, uterus and oviduct were cultural negative. Bulls challenged with Tetratrichomonas sp. remained cultural negative. Since Tetratrichomonas sp. survived only a few hours in the female genitalia and did not survive in the male genitalia after experimental challenge, Tetratrichomonas sp. did not colonize the genital tract. These were likely trichomonads from the digestive tract. Collection of clean samples without fecal contamination from the reproductive tract is proposed as a measure to avoid Tetratrichomonas sp. transitory genital infection.

Animals↗
PubMed1982

Pythiaceous fungi associated with the decomposition of Nymphoides peltata.

Selective isolation procedures were carried out on decaying leaves of Nymphoides peltata (Gmel.) O. Kuntze in order to study the pythiaceous fungi (Peronosporales) associated with the decomposition processes. In addition to Pythium marsipium Drechsler and P. pleroticum T. Ito, a number of Pythium species were isolated with filamentous non-swollen sporangia. Under special culture conditions (in water under a day/night rhythm) sexual reproductive structures of P. diclinum Tokunaga and P. apleroticum Tokunaga were also obtained. However, several isolates designated as Pythium 'F', remained sterile. Within this group three types could be distinguished according to their temperature-growth relationships. As the species recorded have been found very rarely and only one was represented in the CBS collection, detailed descriptions with short discussions are presented.

Fungi↗
PubMed2001

Effect of an acute ergotamine challenge on reproductive hormones in follicular phase heifers and progestin-treated cows.

The objective of this research was to determine if ergotamine, an ergopeptine alkaloid isolated from Neotyphodium-infected grasses and associated with toxicoses in livestock, altered plasma concentrations of reproductive hormones in follicular phase heifers and in cows given a progestin implant. In Experiment 1, blood was sampled for 8h from four cycling heifers 2 days after synchronized luteolysis. Heifers were treated with ergotamine tartrate (19microg/kg) i.v. or saline vehicle in a simple cross-over design after 1h of pre-treatment blood sampling. Heifers received oxytocin (100USP units) i.v. 4h after ergotamine or saline treatment. Ergotamine reduced (P<0.01) prolactin concentrations from 1 to 4h post-treatment and increased (P<0.01) 13,14-dihydro-15-keto prostaglandin F2alpha (PGFM) concentrations from 2 to 5h post-treatment. A PGFM response to oxytocin was not detected. In Experiment 2, blood was sampled for 8h from six cycling cows 10 days after receiving a s.c. norgestomet implant. Cows were treated i.v. with ergotamine (20microg/kg) or saline in a simple cross-over design after 1h of pre-treatment blood sampling. Cows received gonadorelin (GnRH, 100microg) i.v. 1h after ergotamine or saline. Cows received oxytocin (100USP units) i.v. 4h after ergotamine or saline treatment. Ergotamine reduced (P<0.01) serum prolactin concentrations by 120min after treatment, with prolactin returning to pre-treatment concentrations by 200min after treatment. Saline-treated cows had lower (P<0.01) prolactin by 280min after treatment. Ergotamine-treated cows had higher (P<0.01) PGFM concentrations compared to saline-treated cows 120-240min after treatments, but the groups exhibited similar increases in PGFM after oxytocin. Plasma LH and FSH concentrations increased to peaks 100-120min after GnRH for both groups. However, the LH response to GnRH was greater (P<0.01) for ergotamine-treated cows. In summary, ergotamine lowered prolactin and elevated PGFM concentrations in follicular phase heifers and cows on norgestomet therapy. Ergotamine increased the LH response to exogenous GnRH in cows with norgestomet implants. These data highlight the potential of ergopeptine alkaloids to affect reproduction through altered endocrine function.

Animals↗
PubMedDate not supplied

Experimental reproduction of Escherichia coli cellulitis and septicemia in broiler chickens.

Experimental reproduction of avian cellulitis was conducted by subcutaneous inoculation of 25-day-old broiler chickens with a field isolate of serogroup O78 Escherichia coli. Development of the cellulitis lesion occurred as early as 24 h post-infection. Reproduction of cellulitis occurred in 98% of inoculated birds, and E. coli was isolated from > 75% of cellulitis lesions. In addition to cellulitis, other lesions, including pericarditis, airsacculitis, osteomyelitis, arthritis, and perihepatitis, occurred in > 80% of birds inoculated with E. coli. Bacteremia occurred as early as 6 h post-infection and dramatically declined by 5 days post-infection. Seventeen of 59 (29%) birds inoculated with E. coli developed a fatal infection between 1 and 6 days post-infection, and bacteria were isolated from lesions in 98% birds. In contrast, E. coli was not isolated from lesions in birds that survived until days 7-14 post-infection. Birds that survived with cellulitis and other lesions until day 14 post-infection had a significantly lower body weight compared with the control group. This avian model of cellulitis and other lesions will be useful for studying the development of vaccination strategies for E. coli in broilers.

Animals↗
PubMed2026

Intra-individual genetic diversity of vaginal Lactobacillus crispatus revealed through citizen science-driven isolation and pangenome analysis.

AIMS: A vaginal microbiome dominated by Lactobacillus crispatus is associated with positive reproductive and sexual health outcomes, yet intra-individual genetic diversity within this species remains largely unexplored. This study characterized inter- and intra-individual genomic variation in L. crispatus strains isolated through a citizen science initiative and assessed implications for multi-strain probiotic development. METHODS AND RESULTS: Fifty-three women participated in this citizen science project. Self-sampling resulted in 48 shotgun metagenomes. Twenty-two participants isolated their own L. crispatus strains using selective enrichment and LAMP-based species confirmation, resulting in 53 whole-genome-sequenced isolates. Lactobacillus crispatus dominated 20 of 48 metagenomes (50.1%-99.6% relative abundance). Pangenome analysis revealed 3456 gene families, of which 43.7% were core and 56.3% accessory. A 14-kb plasmid harbouring a Fic-domain toxin-antitoxin protein, but devoid of antimicrobial resistance genes, was present in 44 of 53 strains. Strains from the same individual clustered closely together yet harboured 1-123 gene differences. Intra-individual variation was observed in the pullulanase type I gene required for glycogen degradation: 40 strains were predicted to grow on glycogen, six showed genetic disruptions with unknown consequences, and seven were predicted to lack this ability entirely. Variation within individuals was also found for bacteriocin classes and CRISPR-Cas genes. CONCLUSIONS: Substantial functional diversity exists within L. crispatus, even among strains from the same individual, supporting the rationale for multi-strain vaginal probiotics. This citizen science approach enabled discovery of host-specific adaptations while ensuring participant ownership of their strains.

Female↗
PubMed1986

Genetic manipulation of the major histocompatibility complex.

The genes of the major histocompatibility complex (MHC) are prime candidates for genetic engineering of domestic species because of their importance in many biological phenomena, including disease resistance and reproduction. One MHC-linked gene, the Ped gene in the mouse, has been shown to influence embryo development and survival. The Ped gene has mapped to the Qa-2 subregion of the mouse MHC, the H-2 complex. Future studies are aimed at determining, at the DNA and protein levels, the structure of the Ped gene and its gene product. There is preliminary evidence that there may be MHC-linked Ped-like genes that influence reproduction in other species. The search for Ped-like genes in domestic species has been hampered by the limited data available describing the molecular structure of the MHC of species other than mouse and man. This paper describes the use of restriction fragment length polymorphism analysis to study the MHC of two domestic species, the pig and the chicken. Major histocompatibility complex effects on reproduction have been reported for both the pig and the chicken. The long-range goal is to identify and isolate advantageous alleles that could then be injected into recipient embryos to create more reproductively efficient animals.

Animals↗
PubMed1997

[Insertion possibility of 16S-23S space amplification and random amplified polymorphic DNA analysis for typing of methicillin-resistant Staphylococcus aureus strains in the context of nosocomial infections].

Within the scope of the present study n = 183 MRSA isolates from the extended area of Düsseldorf and n = 93 international MRSA strains from seven different countries were typed by pulsed-field gel electrophoresis and two PCR methods (RAPD and 16S-23S-spacer amplification). The isolates could be subdivided into 30 different types by PFGE, into 21 by means of RAPD and 18 by 16S-23S-spacer amplification. PFGE had the highest discriminatory potential, however, a combined use of the three typing methods allows a more detailed differentiation even of those isolates with identical PFGE pattern. Both amplification procedures were rapid, easy in handling with reproductable results. For a temporary epidemiological analysis within 24 hours, both amplification methods could be combined. In case the investigated isolates were still suspected of showing a "clonal identity", they should be analysed by additional PFGE (lasting about four days). Although the international isolates were chosen by random selection, several MRSA strains with identical pattern could be found in different countries of the world. Some RAPD-, spacer- and PFGE pattern were constant over many years. This reflects a high genetic stability of single strains.

Cross Infection↗
PubMed1965

A cytoplasmic character in Neurospora crassa. The role of nuclei and mitochondria.

Nuclear fractions isolated from mutants of Neurospora produced no effect when microinjected into mutants with complementary biochemical requirements. DNA isolated from the nuclear fractions similarly injected also had no effect. Mitochondrial fractions isolated from an abnormal inositolless strain (abn-1) produced drastic changes in the rate of growth, morphology, reproductive characteristics, and cytochrome spectra of normal inositolless strains when single hyphal compartments were microinjected and isolated, whereas the mitochondrial fractions of the wild type produced no effect. These results provide evidence for the transmission of biochemical and biological characters when mitochondria are transferred to new nucleocytoplasmic environments.

Cell Nucleus↗