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PubMed1997

Female social reproductive roles affect central monoamines.

Central monoamines display a variety of activation patterns in different social groups, and among males and females. We addressed three social conditions for female lizards of the species Anolis carolinensis: Isolated, paired with a mate, and in a group of 5 competing for one mate. Among those in a group, only 1 or 2 females exhibited recrudescing ovaries. Individuals paired with a mate (for one month) exhibited ovarian growth, isolated animals (initial controls) had quiescent ovaries. Reproductively dominant females had significantly greater telencephalic 5-HIAA, and serotonergic activation, as indicated by the ratio of 5-HIAA to 5-HT. Telencephalic HVA as well as the HVA/DA ratio were also significantly greater in dominant females compared to all other groups. In contrast, serotonergic activation in brainstem was elevated in subordinate females only. These results suggest that serotonergic activation in telencephalon, found only in dominant females, not in other reproductively active females, is a function of the unique social role of a dominant female, possibly combining submissive behaviors toward a male with dominance over other females and competition for access to that male. Dopaminergic activation in telencephalon, also found only in dominant females, may be related to aggressive interactions with other females. Activation of serotonin in brainstem, found in this study in subordinate females and previously in males [C.H. Summers and N. Greenberg, Activation of central biogenic amines following aggressive interaction in male lizards, Anolis carolinensis, Brain Behav. Evol., 45 (1995) 339-349], may be associated with subordinate social status. Monoamines, involved in social behaviors, appear to be regionally specialized for dominant and subordinate social roles, in males [C.H. Summers and N. Greenberg, Activation of central biogenic amines following aggressive interaction in male lizards, Anolis carolinensis, Brain Behav. Evol., 45 (1995) 339-349][T.R. Summers, E.T. Larson, A.L. Hunter, K.J. Renner, N. Greenberg and C.H. Summers, Amygdalar serotonin mediates long-term social roles following aggressive interaction, Soc. Neurosci. Abs., 22 (1996) 1147] and females. Dominant females exhibit unique social position, behavior and monoamine profile whereas subordinate females and males have a similar serotonergic response in this species.

Aggression↗
PubMed2003

Seasonal reproduction and delayed sexual maturity in mound-building mice Mus spicilegus.

In the mound-building mouse, Mus spicilegus, which is found from Central to Eastern Europe, reproduction is seasonal and limited to spring and summer. In autumn, the mice build voluminous mounds composed of vegetable matter covered with earth, where juvenile animals (autumnal individuals) over-winter in groups without reproducing. Autumnal animals delay reproduction until the next spring when they are 6 months old. The influence and interactions of environmental (short light period and cold temperature (C conditions) compared with long light period and temperate temperature (T conditions)) and social factors (lack of odours from breeding adults (NB conditions) compared with presence of odours from breeding adults (B conditions)) on reproduction and sexual maturation were studied. Forty groups of three autumnal individuals (two males and a female or two females and a male) were placed in four experimental conditions (CB, CNB, TB and TNB), corresponding to interactions between environmental and social factors (n = 10 groups for each condition). Of the 40 groups only one initiated reproduction during the 18 weeks of cohabitation. Subsequently, animals were separated and isolated for 1 month and then paired with unfamiliar partners. Reproduction was monitored for an additional month, and 24 out of 39 females reproduced. In addition, of eight reproducing pairs placed in C conditions and 10 reproducing pairs maintained in T conditions, all but one pair continued reproduction. It was concluded that the delay in reproduction observed in autumnal individuals was the result of the social effects of living in groups as opposed to the environmental conditions of winter.

Animals↗
PubMed2006

Evaluation of the effects of animal age, concurrent bacterial infection, and pathogenicity of porcine reproductive and respiratory syndrome virus on virus concentration in pigs.

OBJECTIVE: To evaluate the influences of animal age, bacterial coinfection, and porcine reproductive and respiratory syndrome virus (PRRSV) isolate pathogenicity on virus concentration in pigs. ANIMALS: Twenty-one 2-month-old pigs and eighteen 6-month-old pigs. PROCEDURE: Pigs were grouped according to age and infected with mildly virulent or virulent isolates of PRRSV. The role of concurrent bacterial infection was assessed by infecting selected pigs with Mycoplasma hyopneumoniae 21 days prior to inoculation with PRRSV. On alternating days, blood and swab specimens of nasal secretions and oropharyngeal secretions were collected. On day 21 after inoculation with PRRSV, selected tissues were harvested. Concentrations of PRRSV were determined by use of quantitative real-time PCR and expressed in units of TCID(50) per milliliter (sera and swab specimens) or TCID(50) per gram (tissue specimens). RESULTS: Concentrations of virus were higher in blood and tonsils of pigs infected with virulent PRRSV. Pigs infected with virulent PRRSV and M hyopneumoniae had significantly higher concentrations of viral RNA in lymphoid and tonsillar tissue. Coinfection with M hyopneumoniae resulted in a higher viral load in oropharyngeal swab specimens and blood samples, independent of virulence of the PRRSV isolate. Two-month-old pigs had significantly higher viral loads in lymph nodes, lungs, and tracheal swab specimens than did 6-month-old pigs, independent of virulence of the PRRSV isolate. CONCLUSIONS AND CLINICAL RELEVANCE: Multiple factors affect PRRSV concentration in pigs, including pathogenicity of the PRRSV isolate, age, and concurrent infection with M hyopneumoniae.

Aging↗
PubMed2003

Wood ingestion by passalid beetles in the presence of xylose-fermenting gut yeasts.

During a survey of insect gut micro-organisms, we consistently isolated Pichia stipitis-like yeasts (Fungi: Ascomycota, Saccharomycetes) from the wood-ingesting beetles, Odontotaenius disjunctus and Verres sternbergianus (Coleoptera: Passalidae). The yeasts were isolated from passalid beetles over a wide area, including the eastern and midwestern USA and Panama. Phylogenetic analyses of the nuclear encoded small and large subunit rRNA gene (rDNA) sequences distinguished a well-supported clade consisting of the passalid yeasts and Pichia stipitis, P. segobiensis, Candida shehatae and C. ergatensis. Members of this clade have the ability to ferment and assimilate xylose or to hydrolyse xylan, major components of the polysaccharide, hemicellulose. Sexual reproduction was present in the passalid isolates but was rare among the gut yeasts of other beetles to which they were compared. Minor genetic and phenotypic variation among some of the passalid yeasts was detected using markers from the internal transcribed spacer region of the rDNA repeat unit, morphology, and in vitro metabolic tests. The consistent association of xylose-fermenting yeasts of almost identical genotypes with passalid beetles across a broad geographical distribution, suggests a significant symbiotic association.

Animals↗
PubMed1993

Selection for a strain of Haemonchus contortus that exhibits periparturient egg rise in sheep.

Periparturient egg rise (PPR) is a principal means for some nematode parasites to survive over winter and to provide transmission of infective larvae from ewes to lambs during the spring. Routine laboratory propagation techniques probably have selected for those characteristics that would not promote PPR in conventional laboratory strains of Haemonchus contortus. An established isolate of H. contortus (BPL) was the source of the initial inoculum to select for a strain that readily exhibits characteristics of PPR. The selection process included inoculation of helminth-free pregnant ewes during mid-gestation, collection of nematode eggs during lactation, and storage of infective larvae at 4 C for 4 mo. After 10 generations, the 2 strains, BPL and PPR from lambs and pregnant ewes were compared for reproductive, morphological, and population differences in lambs and pregnant ewes. After lambing, ewes inoculated with the PPR strain had significantly higher fecal egg concentrations. Lambs inoculated with the PPR strain had higher egg concentrations, higher total daily egg production, fewer adult worms, larger female worms, and higher fecundity. Repeated selection in the appropriate host, after prolonged storage of the inoculum, produced a PPR strain of H. contortus morphologically and reproductively distinct from the initial source isolate.

Animals↗
PubMed1985

Clinical significance of focal pelvic endometriosis.

Clinical findings in a group of infertile patients with endometriosis were reviewed to determine if minimal (focal) disease exerted an effect on reproductive outcome. Focal disease, defined as isolated implants less than or equal to 5 mm without pelvic adhesions or anatomic distortion, was found in 69 patients, with 35% manifesting menstrual dysfunction/anovulation. Patients with focal disease were divided into two groups: those treated with danazol (400-800 mg) daily for six months and those not treated. Conception occurred in 71% of the danazol-treated patients and 30% of the untreated ones. These results suggest that focal endometriosis does influence reproductive performance and that infertile patients with focal disease should be treated more aggressively with the available medical regimens, particularly when the infertility is of significant duration or when routine therapy has failed.

Danazol↗
PubMed2002

Primary infertility associated with isolated cervical collecting diverticulum.

OBJECTIVE: To describe a previously unreported isolated congenital cervical diverticulum and its gynecologic, reproductive, and obstetrical implications. DESIGN: Case report. SETTING: A university hospital. PATIENT: A 31-year-old woman presenting with menometrorrhagia and primary infertility. Investigation revealed an isolated collecting cervical diverticulum causing prolonged postmenstrual spotting, possibly interfering with sperm capacitation and access to the uterine cavity. INTERVENTION(S): The examination included hysterosalpingography and magnetic resonance imaging. The combined hysteroscopy and laparoscopy revealed a 5 x 5 cm cervical diverticulum, around 1 cm from the external cervical os, leading to a short cervical canal connected to a normal uterine cavity. The patient achieved a pregnancy after controlled ovarian hyperstimulation and ultrasonographically guided intrauterine insemination. MAIN OTUCOME MEASURE(S): Pregnancy and obstetrical outcome. RESULT(S): Extensive evaluation revealed the patient's condition to be a previously undescribed congenital cervical anomaly. The patient's infertility was corrected by ovulation induction and sonographically guided intrauterine insemination, which resulted in a twin pregnancy. After 27 weeks of gestation, preterm labor complicated the delivery. CONCLUSION(S): The diagnosis and management of this unusual congenital cervical diverticulum present a particular challenge, as this congenital abnormality has not been previously described or reported.

Adult↗
PubMed1996

Phylogenetic relationships of european strains of porcine reproductive and respiratory syndrome virus (PRRSV) inferred from DNA sequences of putative ORF-5 and ORF-7 genes.

The complete ORF-5 gene and a fragment of the ORF-7 gene from 14 different European porcine reproductive and respiratory syndrome virus (PRRSV) isolates were amplified by reverse transcriptase polymerase chain reaction (RT-PCR), and their nucleotide sequences were determined. The ORF-7 gene displayed nucleotide and amino acid identities of 94.1-99.6% and 95.3-100% among isolates from different countries. The ORF-5 gene showed higher nucleotide (87.1-99.2% identity) and amino acid (-88% identity) variability. The resulting sequences were aligned with other European and North American PRRSV strains and phylogenetic relationships among these strains were established by the maximum parsimony method. The phylogenetic trees inferred from both genes were in agreement and showed that European and North American PRRSV strains clearly represent two different genotypes. According to both trees, there is a perfect correlation between strains and the countries in which they were isolated. Additionally, the phylogenetic position of European and North American PRRSV strains within the recently proposed family Arteriviridae was also analyzed.

Animals↗
PubMed1990

Reproduction of inclusion body hepatitis in conventionally raised chickens inoculated with a New Zealand isolate of avian adenovirus.

Conventionally raised chickens were inoculated with a local isolate of serotype 8 of avian adenovirus by an oral or intraperitoneal route, or were exposed to the infection by contact. Fatal hepatitis, resembling inclusion body hepatitis, occurred in 30% and 45% of the birds inoculated by the oral and intraperitoneal routes respectively, and severe growth depression was recorded in survivors and in birds in contact. Birds which had maternally derived virus neutralising antibody titres of 64 or greater at the time of viral exposure did not succumb to fatal infection, but their growth rates were significantly depressed.

Journal Article↗
PubMedDate not supplied

[Intranasal infection in mice inoculated with cowpox virus strain EP-2 isolated from the elephant].

The specific features of reproduction of EP-2 strain of cowpox virus (CPV) were studied in intranasally infected BALC/C mice by light and electron microscopy. Virus replication was found in the ciliated, intercalary, basal, and goblet cells (the nasal respiratory area), basal and supporting cells (the nasal olfactory area), ciliated, intercalary, goblet cells (the tracheal and bronchial epithelium), and collagen-producing, Schwann's, endothelial, smooth muscle, and adventitial cells. It has been shown that the CPV strain EP-2 locally replicates in the nasal cavity, trachea, and large bronchi and that there is no generalized infection.

Animals↗
PubMed1985

Epizootics of respiratory tract disease in swine in Belgium due to H3N2 influenza virus and experimental reproduction of disease.

In Belgium, influenza virus was isolated from swine in 22 epizootics of respiratory tract disease in swine during 1984. In 8 of the epizootics, H3N2 influenza virus, related to the A/Port Chalmers/1/73 strain, was isolated. Intratracheal inoculation of the isolates induced clinical signs. It was concluded that the A/Port Chalmers/1/73 strain was established in the Belgian swine population and was responsible for the epizootics of respiratory tract disease in swine.

Animals↗
PubMed1998

Genomic and antigenic variations of porcine reproductive and respiratory syndrome virus major envelope GP5 glycoprotein.

The objective of the present study was to evaluate the importance of genomic and antigenic variations which may have affected the major envelope glycoprotein GP5 of porcine reproductive and respiratory syndrome virus (PRRSV) isolates responsible for outbreaks in Quebec and Ontario, in comparison with the modified-live U.S. vaccine strain (MLV) and the European prototype strain from Lelystad (LV). Nucleotide sequence analyses of the open reading frame (ORF)5 genes showed that all of the isolates studied were heterogenous, amino acid (aa) identities varied from 88 to 99% with the MLV strain, and between 51 and 54% with the LV strain. The aa substitutions were randomly scattered across the protein, although one region between residues 26 and 39 was found to correspond to a hypervariable region which involved 0 to 3 potential N-glycosylation sites. The ORF5 encoded products of 5 of these isolates, including the MLV and LV strains, were expressed in E. coli as recombinant proteins fused to the glutathione S-transferase (GST) protein and used to raise hyperimmune anti-ORF5 sera in rabbits. The reactivity patterns of strain-specific hyperimmune anti-ORF5 sera and a panel of 4 monoclonal antibodies directed against the ORF5 gene product of the Quebec IAF-Klop strain of PRRSV, indicated that GP5 of field isolates also underwent antigenic variations. The data suggest that neutralizing epitopes, independent of conformation and glycosylation, are also associated with antigenic variability of the GP5 of PRRSV.

Amino Acid Sequence↗
PubMed1975

In vitro contractile activity of the mesotubarium superius from the rabbit oviduct in various endocrine states.

We investigated the influence of estrogen on the contractile activity of smooth muscle in the nonpregnant female reproductive tract, using as a model isolated strips of mesotubarium superius (MTS) removed from the rabbit oviduct. We studied four physiologic states in which muscular activity was influenced to varying degrees by endogenous estrogen. Normal estrous (estrogen dominated) rabbits were used as controls. We observed decreased activity in MTS from rabbits chronically deprived of estrogen (60) days postovariectomy). However, a dramatic increase in activity occurred in response to acute withdrawal of ovarian function (12 hours postovariectomy). An increase in activity also occurred at the time of ovulation. We concluded that acute withdrawal of endogenous estrogen is a potent stimulus to reproductive smooth muscle in the female rabbit and that it might contribute to increased muscular activity at ovulation.

Animals↗
PubMed2003

Genetic diversity and phylogenetic analysis of glycoprotein 5 of European-type porcine reproductive and respiratory virus strains in Spain.

The gene encoding glycoprotein 5 (ORF5) of 21 porcine reproductive and respiratory syndrome virus (PRRSV) isolates from Spain and two European-type vaccines currently available in that country were analysed using RT-PCR and sequencing. Sequences were then compared with other European-type sequences available through GenBank. Results showed percentages of similarity to Lelystad virus (LV), which, in most cases, were below 90 %. In contrast, two strains were very similar (>99 %) to a PRRSV variant from the Czech Republic. Evolutionary trees showed three types of strains: one grouped old Spanish sequences; a second grouped isolates from this study together with two Czech variant strains; and the third comprised other GenBank sequences. Regarding the predicted protein sequences, some isolates from this study showed a low degree of similarity to LV (below 50 %) and most of the strains examined had additional N-linked glycosylation sites compared to LV. These results provide evidence of the existence of variant PRRSV strains in Spain with characteristics that may be advantageous for immune evasion.

Animals↗
PubMedDate not supplied

Developmental constraints on the mode of reproduction in the facultatively parthenogenetic cockroach Nauphoeta cinerea.

Considerable work in evolutionary biology has focused on the question of why sex persists. Both advantages to sex and constraints limiting a return to asexual reproduction are hypothesized to maintain sex once it evolves. Developmental constraints would limit asexual reproduction from a sexual species if it were difficult for females to switch from making eggs that do not develop without fertilization to making zygotes that are capable of developing in the absence of fertilization. Nauphoeta cinerea is an ovoviviparous cockroach in which some females are capable of switching from a sexual mode of reproduction to an asexual mode when isolated from males. Yet, while facultative parthenogenesis can occur in individuals, few females make the switch. Thus, this cockroach provides an ideal system for examining the potential role of developmental constraints in maintaining sex. Here we compare the cytogenetics and embryonic development of sexual and parthenogenetic offspring in N. cinerea. We find that deviations from normal ploidy levels are associated with abnormal development. All viable N. cinerea embryos exhibit typically hemimetabolous insect embryogenesis. Although there is no variation among embryos in development within a sexually produced clutch, we see extreme variation in asexually derived clutches. These results suggest that developmental constraints limit the success of asexual reproduction in this facultatively parthenogenetic cockroach. Our data further suggest that the specific constraint occurs in the switch from a meiotic mode of reproduction requiring fertilization to diploid zygotes that develop in the absence of fertilization.

Animals↗
PubMed2003

Isolation and characterization of normal adult human epithelial pluripotent stem cells.

Both reproductive and therapeutic cloning of human stem cells have been made possible with recent technological advances in the isolation of embryonic stem cells and of pluripotent stem cells from adult tissues. We have isolated normal human kidney and human breast epithelial stem cells, as well as having characterized "immortalized" cells from human neuronal and human pancreatic tissue (Trosko et al., Methods 20:245-264, 2000). The isolation was motivated by the stem cell theory of carcinogenesis. Based on the assumption that stem cells would not express connexin genes, nor have functional gap junctional intercellular communication (GJIC), we have demonstrated that the human kidney, breast, neuronal, and pancreatic stem cells can divide either symmetrically or asymmetrically, depending on whether they are grown in microenvironmental conditions that suppress GJIC (the undifferentiated, proliferative state) or induce GJIC (the differentiated state). Normal breast epithelial stem cells appear to be intrinsically "immortal" until induced to express GJIC, at which time, with appropriate substrate and microenvironmental nutrients, they can form three-dimensional "organoids." expressing markers associated with the mature mammary tissue and forming a physical structure very similar to the in vivo budding, ductal structures. The breast stem cells can be prevented from "mortalizing" and can be converted to neoplastic cells, which maintain many phenotypes of the stem cells.

Adult↗