WorldWideScience
 
 
1

Status and mating success amongst visual artists.  

UK PubMed Central (United Kingdom)

Geoffrey Miller has hypothesized that producing artwork functions as a mating display. Here we investigate the relationship between mating success and artistic success in a sample of 236 visual artists. Initially, we derived a measure of artistic success that covered a broad range of artistic behaviors and beliefs. As predicted by Miller's evolutionary theory, more successful male artists had more sexual partners than less successful artists but this did not hold for female artists. Also, male artists with greater artistic success had a mating strategy based on longer term relationships. Overall the results provide partial support for the sexual selection hypothesis for the function of visual art.

Clegg H; Nettle D; Miell D

2011-01-01

2

The role of ego-identity status in mating preferences.  

UK PubMed Central (United Kingdom)

This study was designed to examine the role ego-identity plays in the mating preferences of late adolescents. In addition to examining the variance in mating preferences explained by ego-identity status, it was hoped that the results could assist in testing the competing Sexual Strategies (Buss & Schmitt, 1993) and Social Role (Eagly & Wood, 1999) theories. Ego-identity and the sex of the participant accounted for a significant amount of variance in the number of sexual partners desired and the penchant for short-term mating. The sex of the participant was the lone predictor of the importance placed on the mate characteristics of physical attractiveness and earning capacity with females placing more emphasis on the former and males placing more emphasis on the latter characteristic.

Dunkel CS; Papini DR

2005-01-01

3

Mate retention tactics in Spain: personality, sex differences, and relationship status.  

UK PubMed Central (United Kingdom)

Mate retention is an important problem in romantic relationships because of mate poachers, infidelity, and the risk of outright defection. The current study (N=892) represents the first study of mate retention tactics conducted in Spain. We tested hypotheses about the effects of gender, relationship commitment status, and personality on mate retention tactics. Women and men differed in the use of resource display, appearance enhancement, intrasexual violence, and submission/self-abasement as mate retention tactics. Those in more committed relationships reported higher levels of resource display, appearance enhancement, love, and verbal signals of possession. Those in less committed relationships more often reported intentionally evoking jealousy in their partner as a mate retention tactic. Personality characteristics, particularly Neuroticism and Agreeableness, correlated in coherent ways with mate retention tactics, supporting two evolution-based hypotheses. Discussion focuses on the implications, future research directions, and interdisciplinary syntheses emerging between personality and social psychology and evolutionary psychology.

de Miguel A; Buss DM

2011-06-01

4

Approach to Syncope and Altered Mental Status.  

UK PubMed Central (United Kingdom)

Children who present with an episode of altered mental status, whether transient or persistent, present a diagnostic challenge for practitioners. This article describes some of the more common causes of altered mental status and delineates a rational approach to these patients. This will help practitioners recognize the life-threatening causes of these frightening presentations as well as help avoid unnecessary testing for the more benign causes.

Macneill EC; Vashist S

2013-10-01

5

Reproductive status alters transcriptomic response to infection in female Drosophila melanogaster.  

UK PubMed Central (United Kingdom)

Mating and consequent reproduction significantly reduce the ability of female Drosophila melanogaster to defend against systemic bacterial infection. The goal of the present study was to identify genes likely to inform the mechanism of this post-mating immunosuppression. We used microarrays to contrast genome-wide transcript levels in virgin vs. mated females before and after infection. Because the immunosuppressive effect of mating is contingent on the presence of a germline in females, we repeated the entire experiment by using female mutants that do not form a germline. We found that multiple genes involved in egg production show reduced expression in response to infection, and that this reduction is stronger in virgins than it is in mated females. In germline-less females, expression of egg-production genes was predictably low and not differentially affected by infection. We also identified several immune responsive genes that are differentially induced after infection in virgins vs. mated females. Immune genes affected by mating status and egg production genes altered by infection are candidates to inform the mechanism of the trade-off between mating and immune defense.

Short SM; Lazzaro BP

2013-05-01

6

Virgins in the wild: mating status affects the behavior of a parasitoid foraging in the field.  

UK PubMed Central (United Kingdom)

In haplodiploid organisms, virgin females can produce offspring, albeit only sons. They may therefore face a trade-off between either: (1) searching for hosts and producing sons immediately; or (2) searching for mates and perhaps producing both sons and daughters later in life. Although this trade-off raises a theoretical interest, it has not been approached experimentally. The objective of this article is thus to document the effect of mating status on the foraging behavior of a haplodiploid parasitoid. For this, we recorded the behavior of virgin and mated female Lysiphlebus testaceipes (Hymenoptera: Braconidae) after being released, in the field, on a colony of their aphid hosts. Half of the virgin females were mated by a wild male after less than 10 min of foraging. Evidently, virgin females attract males while foraging on host patches, so that the two activities are not mutually exclusive. Nonetheless, virgin females stayed motionless more often and for longer periods than mated females. Consequently, they attacked aphids at a lower rate, and in turn, attacked fewer aphids on each patch. Moreover, contrary to mated females, virgins did not aggregate their progeny on large patches. We conclude that in L. testaceipes, the trade-off may not be as hypothesized. By dispersing across patches more than mated females, virgins could promote future mating opportunities for their sons and increase their inclusive fitness. However, by moving too frequently, females may lose immediate mating opportunities for themselves and the immediate advantage of producing offspring of both sexes. The observed behavior of virgin L. testaceipes females on host patches could reflect an optimal solution to such a trade-off.

Fauvergue X; Lo Genco A; Lo Pinto M

2008-07-01

7

Virgins in the wild: mating status affects the behavior of a parasitoid foraging in the field.  

Science.gov (United States)

In haplodiploid organisms, virgin females can produce offspring, albeit only sons. They may therefore face a trade-off between either: (1) searching for hosts and producing sons immediately; or (2) searching for mates and perhaps producing both sons and daughters later in life. Although this trade-off raises a theoretical interest, it has not been approached experimentally. The objective of this article is thus to document the effect of mating status on the foraging behavior of a haplodiploid parasitoid. For this, we recorded the behavior of virgin and mated female Lysiphlebus testaceipes (Hymenoptera: Braconidae) after being released, in the field, on a colony of their aphid hosts. Half of the virgin females were mated by a wild male after less than 10 min of foraging. Evidently, virgin females attract males while foraging on host patches, so that the two activities are not mutually exclusive. Nonetheless, virgin females stayed motionless more often and for longer periods than mated females. Consequently, they attacked aphids at a lower rate, and in turn, attacked fewer aphids on each patch. Moreover, contrary to mated females, virgins did not aggregate their progeny on large patches. We conclude that in L. testaceipes, the trade-off may not be as hypothesized. By dispersing across patches more than mated females, virgins could promote future mating opportunities for their sons and increase their inclusive fitness. However, by moving too frequently, females may lose immediate mating opportunities for themselves and the immediate advantage of producing offspring of both sexes. The observed behavior of virgin L. testaceipes females on host patches could reflect an optimal solution to such a trade-off. PMID:18446375

Fauvergue, Xavier; Lo Genco, Alessandro; Lo Pinto, Mirella

2008-04-29

8

Reproduction of the western tarnished plant bug, Lygus hesperus, in relation to age, gonadal activity and mating status.  

UK PubMed Central (United Kingdom)

Understanding the basic life history and underlying regulatory mechanisms for a pest insect is essential for developing targeted control strategies, but for many insects relatively little is known. Although the western tarnished plant bug, Lygus hesperus Knight (Heteroptera: Miridae) has a substantial negative impact in the western U.S., its basic biology is poorly characterized. To elucidate the regulation of L. hesperus reproductive dynamics, the onset times of gonadal activation and mating behavior were examined in young adults. Newly emerged adults reared under laboratory conditions at 25 degrees C were monitored daily for changes in gamete production and willingness to mate. Males matured more quickly than females. Sperm was present at emergence and a small proportion of males were willing to mate as early as 2 days post-emergence. Females were unwilling to mate until at least 5 days post-emergence, although many produced choriogenic oocytes by 4 days. Males appeared to discriminate female age and were more likely to attempt mating with females >5 days post-emergence than with younger females. Males were also able to detect previous mating and attempted to mount virgins more often than recently inseminated females. Collectively these results indicate that the changes in the mating behaviors of L. hesperus are linked to reproductive status, although there is a lag between gamete production and willingness to mate. The results also suggest that interactions of the sexes are chemically mediated.

Brent CS

2010-01-01

9

Theoretical influence of female mating status and remating propensity on male sperm allocation patterns  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Theoretical models predict that males should allocate more sperm in matings where the immediate risk of sperm competition is high. It has therefore often been argued that males should invest less sperm in matings with virgin females compared with matings with already mated females. However, with rel...

Engqvist, Leif; Reinhold, Klaus

10

A male sex pheromone in a parasitic wasp and control of the behavioral response by the female's mating status.  

UK PubMed Central (United Kingdom)

Male insects may increase their chance of successful reproduction by releasing pheromones that attract females or elicit sexual acceptance. In parasitic wasps, male pheromones have been suggested for a few species but no chemicals have been identified so far. Here we report the first identification of a male sex pheromone in parasitic Hymenoptera. In abdomens of male jewel wasps, Nasonia vitripennis Walker, we found a mixture of (4R,5R)- and (4R,5S)-5-hydroxy-4-decanolide (HDL), which was released intermittently and attracted virgin females, but no males, in an olfactometer bioassay. However, only a few minutes after copulation mated females avoided the male-derived pheromone. Neither preference nor avoidance was shown by mated females after 24 h and even after they had been allowed to oviposit for 6 days. Nasonia vitripennis females normally mate only once. Thus, their variable response to the sex attractant depending on the mating status makes sense from an evolutionary perspective. Firstly, it increases the chance of virgins to be inseminated. Secondly, by terminating the response or even avoiding the male pheromone, mated females decrease the probability of encountering males and being disturbed by their courtship activities when searching for new oviposition sites.

Ruther J; Stahl LM; Steiner S; Garbe LA; Tolasch T

2007-06-01

11

Altered taste perception and nutritional status among hemodialysis patients.  

UK PubMed Central (United Kingdom)

OBJECTIVE: The objective of this study was to examine the association between altered taste perception and nutritional status among hemodialysis patients. DESIGN: We performed a post hoc analysis of data from the Hemodialysis study (n = 1,745). Taste perception was assessed at baseline and then updated annually using an item from a quality of life survey that asked "During the past 4 weeks, to what extent were you bothered by loss of taste?" Responses were categorized as normal taste perception if subjects answered "not at all" or altered taste perception if they reported any degree of bother. Time-updated logistic regression models were used to evaluate predictors of altered taste perception. Time-updated linear regression models were used to examine the association between altered taste perception and indices of nutritional status. Multivariable proportional hazards and Poisson models were used to assess association between altered taste perception and mortality and hospitalization, respectively. RESULTS: At baseline, 34.6% reported altered taste perception, which was associated with poorer baseline nutritional status. On time-updated analysis, altered taste perception was associated with a persistently higher proportion of subjects requiring enteral nutritional supplements and lower serum albumin, serum creatinine, normalized protein catabolic rate, protein intake, sodium intake, and mid-arm muscle circumference. Altered taste perception at baseline was independently associated with increased all-cause mortality: adjusted hazard ratio (95% confidence interval) of 1.17 (1.01-1.37), although not with increased rate of hospitalization. CONCLUSION: Altered taste perception was common among prevalent hemodialysis patients and was independently associated with poorer indices of nutritional status and increased all-cause mortality.

Lynch KE; Lynch R; Curhan GC; Brunelli SM

2013-07-01

12

The smell of virgins: mating status of females affects male swimming behaviour in Oithona davisae  

DEFF Research Database (Denmark)

Many copepod species rely on pheromone cues to find partners. Some parasitic and benthic copepod males are able to distinguish between females of different reproductive states. Here, we demonstrate that the swimming activity and velocity of males of a pelagic copepod, Oithona davisae, increases in the presence of virgin when compared with mated females and that the cue is waterborne. The ability to distinguish between virgin and mated females may reduce male mortality during mate search and the cost related to mating behaviour (precopula) in both sexes. We estimate that at realistic population densities the ability of males to distinguish between virgin and mated females saves them several hours per day of dangerous and energetically expensive fast female tracking

Heuschele, Jan; KiØrboe, Thomas

2012-01-01

13

Effects of mate tea (Ilex paraguariensis) ingestion on mRNA expression of antioxidant enzymes, lipid peroxidation, and total antioxidant status in healthy young women.  

UK PubMed Central (United Kingdom)

The antioxidant activity of mate tea, the roasted product derived from yerba mate (Ilex paraguarienis), was observed in vitro and in animal models, but studies in humans are lacking. The aim of this study was to investigate the effects of mate tea supplementation on plasma susceptibility to oxidation and on antioxidant enzyme gene expression in healthy nonsmoking women, after acute or prolonged ingestion. We evaluated plasma total antioxidant status (TAS), the kinetics of diene conjugate generation, and thiobarbituric acid reactive substance (TBARS) contents in plasma, as well as mRNA levels of antioxidant gluthatione peroxidase (GPx), superoxide dismutase (SOD), and catalase (CAT). After the supplementation period with mate tea, lipid peroxidation was acutely lowered, an effect that was maintained after prolonged administration. Total antioxidant status and the level of antioxidant enzyme gene expression were also demonstrated after prolonged consumption. These results suggest that regular consumption of mate tea may increase antioxidant defense of the body by multiple mechanisms.

Matsumoto RL; Bastos DH; Mendonça S; Nunes VS; Bartchewsky W; Ribeiro ML; de Oliveira Carvalho P

2009-03-01

14

Effects of mate tea (Ilex paraguariensis) ingestion on mRNA expression of antioxidant enzymes, lipid peroxidation, and total antioxidant status in healthy young women.  

Science.gov (United States)

The antioxidant activity of mate tea, the roasted product derived from yerba mate (Ilex paraguarienis), was observed in vitro and in animal models, but studies in humans are lacking. The aim of this study was to investigate the effects of mate tea supplementation on plasma susceptibility to oxidation and on antioxidant enzyme gene expression in healthy nonsmoking women, after acute or prolonged ingestion. We evaluated plasma total antioxidant status (TAS), the kinetics of diene conjugate generation, and thiobarbituric acid reactive substance (TBARS) contents in plasma, as well as mRNA levels of antioxidant gluthatione peroxidase (GPx), superoxide dismutase (SOD), and catalase (CAT). After the supplementation period with mate tea, lipid peroxidation was acutely lowered, an effect that was maintained after prolonged administration. Total antioxidant status and the level of antioxidant enzyme gene expression were also demonstrated after prolonged consumption. These results suggest that regular consumption of mate tea may increase antioxidant defense of the body by multiple mechanisms. PMID:19219987

Matsumoto, Ruth L T; Bastos, Deborah H M; Mendonça, Simone; Nunes, Valéria S; Bartchewsky, Waldemar; Ribeiro, Marcelo L; de Oliveira Carvalho, Patrícia

2009-03-11

15

Altered mental status in older patients in the emergency department.  

Science.gov (United States)

Altered mental status is a common chief compliant among older patients in the emergency department (ED). Acute changes in mental status are more concerning and are usually secondary to delirium, stupor, and coma. Although stupor and coma are easily identifiable, the clinical presentation of delirium can be subtle and is often missed without actively screening for it. For patients with acute changes in mental status the ED evaluation should focus on searching for the underlying etiology. Infection is one of the most common precipitants of delirium, but multiple causes may exist concurrently. PMID:23177603

Han, Jin H; Wilber, Scott T

2013-02-01

16

Altered mental status in older patients in the emergency department.  

UK PubMed Central (United Kingdom)

Altered mental status is a common chief compliant among older patients in the emergency department (ED). Acute changes in mental status are more concerning and are usually secondary to delirium, stupor, and coma. Although stupor and coma are easily identifiable, the clinical presentation of delirium can be subtle and is often missed without actively screening for it. For patients with acute changes in mental status the ED evaluation should focus on searching for the underlying etiology. Infection is one of the most common precipitants of delirium, but multiple causes may exist concurrently.

Han JH; Wilber ST

2013-02-01

17

Acute onset altered mental status in a previously healthy teenager.  

UK PubMed Central (United Kingdom)

Evans syndrome is a rare disease characterized by autoimmune hemolytic anemia and thrombocytopenia. Its initial presentation with intracranial hemorrhage is rare. We report a case of a 12-year-old girl who presented to the emergency department with altered mental status secondary to an intracranial hemorrhage and later diagnosed to have Evans syndrome.

Akbary S; Kannikeswaran N

2012-04-01

18

Antacids, Altered Mental Status, and Milk-Alkali Syndrome  

Science.gov (United States)

The frequency of milk-alkali syndrome decreased rapidly after the development of histamine-2 antagonists and proton pump inhibitors for the treatment of peptic ulcer disease; however, the availability and overconsumption of antacids and calcium supplements can still place patients at risk (D. P. Beall et al., 2006). Here we describe a patient who presented with altered mental status, hypercalcemia, metabolic alkalosis, and acute renal failure in the context of ingesting large amounts of antacids to control dyspepsia.

Watson, Simon C.; Dellinger, Bonnie B.; Jennings, Katie; Scott, Lancer A.

2012-01-01

19

Antacids, altered mental status, and milk-alkali syndrome.  

UK PubMed Central (United Kingdom)

The frequency of milk-alkali syndrome decreased rapidly after the development of histamine-2 antagonists and proton pump inhibitors for the treatment of peptic ulcer disease; however, the availability and overconsumption of antacids and calcium supplements can still place patients at risk (D. P. Beall et al., 2006). Here we describe a patient who presented with altered mental status, hypercalcemia, metabolic alkalosis, and acute renal failure in the context of ingesting large amounts of antacids to control dyspepsia.

Watson SC; Dellinger BB; Jennings K; Scott LA

2012-01-01

20

Chickpea Ascochyta Blight: Disease Status and Pathogen Mating Type Distribution in Syria  

UK PubMed Central (United Kingdom)

Chickpea fields were surveyed in nine major chickpea-growing provinces of Syria in 2008 and 2009 to determine the prevalence and severity of Ascochyta blight, and the distribution of Didymella rabiei mating types (MATs) in the country. A total of 133 Ascochyta rabiei isolates were assayed for mating type, including isolates from older collections that date back to 1982. Multiplex MAT-specific PCR with three primers was used for MAT analysis. Out of the 133 tested isolates, 64% were MAT1-1 and 36% were MAT1-2. Both MATs were found in six provinces but MAT1-1 alone was found in three provinces. Chi-squared analysis was used to test for a 1 : 1 ratio of MAT frequencies in all samples. The MAT ratios in the six provinces were not significantly different from 1 : 1, suggesting that there is random mating of the pathogen population under natural conditions. The presence of the two MATs is expected to play a role in the evolution of novel virulence genes that could threaten currently resistant chickpea varieties. Overall analysis of the 133 isolates showed a significant deviation from the 1 : 1 ratio with almost twice as many MAT1-1 isolates than MAT1-2 isolates, which indicates a competitive advantage associated with MAT1-1 in Syria. However, the overall picture of an unequal frequency in MATs indicates that there may be limited sexual recombination occurring in the Syrian population.

Atik O; Baum M; El-Ahmed A; Ahmed S; Abang MM; Yabrak MM; Murad S; Kabbabeh S; Hamwieh A

2011-06-01

 
 
 
 
21

Fertility status and distribution of mating type alleles of the rice blast fungus, Magnaporthe grisea in northern Iran.  

Science.gov (United States)

This study was carried out using 155 monoconidial isolates collected from different areas of two major rice growing provinces in northern Iran, including 94 isolates from Guilan and 59 isolates from Mazandaran. Among 94 isolates from Guilan, 92 and two isolates recovered from rice and crabgrass (Digitaria sp.), respectively. All 61 rested isolates from Mazandaran were recovered from rice. All isolates were evaluated for in vitro sexual fertility and mating type status by pairing with Mat 1-1 and Mat 1-2 fertile standard hermaphrodite isolates including Br48 and Th12 (Mat 1-1) and KA9 and TH16 (Mat 1-2). Of 155 isolates, 98 (63.2%) were fertile and 57 (36.8%) were infertile and produced no perithecium when mated with standard isolates. Among 98 fertile isolates, 96 isolates were identified as Mat 1-1 and two isolates as Mat 1-2. All Mat 1-1 isolates were obtained from rice and two Mat 1-2 isolates obtained from crab grass. No Mat 1-2 isolate was identified from rice in this study. Both mating types were found in Guilan but all isolates recovered from Mazandaran were identified as Mat 1-1. Male fertility predominated in fertile Mat 1-1 and Mat 1-2 isolates from all sampling sites in northern Iran, and no female fertility was detected. This is the first report of existence of Mat 1-2 allele in Magnaporthe grisea population in Iran. PMID:15756836

Hemmati, R; Javan-Nikkhahi, M; Hedjaroude, Gh A; Okhovvat, S M; Moosanejad, S

2004-01-01

22

Ovarian dynamics, egg size, and egg number in relation to temperature and mating status in a butterfly  

UK PubMed Central (United Kingdom)

Although the temperature-size rule, that is, an increase in egg (and body) size at lower temperatures, applies almost universally to ectotherms, the developmental mechanisms underlying this consistent pattern of phenotypic plasticity are hitherto unknown. By investigating ovarian dynamics and reproductive output in the tropical butterfly Bicyclus anynana (Butler) (Lepidoptera: Nymphalidae: Satyrinae) in relation to oviposition temperature and mating status, we tested the relevance of several competing hypotheses for temperature-mediated variation in egg size and number. As expected, females ovipositing at a lower temperature laid fewer but larger eggs than those ovipositing at a higher temperature. Despite pronounced differences in egg-laying rates, oocyte numbers were equal across temperatures at any given time, while oocyte size increased at the lower temperature. In contrast, there were greatly reduced oocyte numbers in mated compared to virgin females. Our results indicated that temperature-mediated plasticity in egg size cannot be explained by reduced costs of somatic maintenance at lower temperatures, enabling the allocation of more resources to reproduction (reproductive investment was higher at the higher temperature). Furthermore, there was no indication for delayed oviposition (no accumulation of oocytes at the lower temperature, in contrast to virgin females). Rather, low temperatures greatly reduced the oocyte production (i.e., differentiation) rate and prolonged egg-maturation time, causing low egg-laying rates. Our data thus suggested that oocyte growth is less sensitive to temperature than oocyte production, resulting in a lower number of larger eggs at lower temperatures.

Steigenga MarcJ; Fischer Klaus

2007-11-01

23

Changes in mate recognition through alterations of pheromones and receptors in the multisexual mushroom fungus Schizophyllum commune.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Schizophyllum commune has thousands of mating types defined in part by numerous lipopeptide pheromones and their G-protein-coupled receptors. These molecules are encoded within multiple versions of two redundantly functioning B mating-type loci, B alpha and B beta. Compatible combinations of pheromo...

Fowler, T J; Mitton, M F; Vaillancourt, L J; Raper, C A

24

Altered mental status in cirrhosis: etiologies and outcomes.  

UK PubMed Central (United Kingdom)

BACKGROUND: Cirrhotic patients admitted with altered mental status (AMS) represent a clinical challenge, as many potentially life-threatening diseases must be considered. Although many patients with AMS have hepatic encephalopathy (HE), other causes of AMS occur, and we hypothesized that these may have different outcomes. AIM: We aimed to understand the causes of AMS in cirrhotic patients admitted to the hospital and investigate their associated outcomes. METHODS: We performed a retrospective cohort study in 1218 inpatients with cirrhosis. Altered mental status was defined a priori (HE, sepsis/infectious, metabolic, exogenous drugs/toxins, structural lesions, or psychiatric abnormalities). RESULTS: Patients with AMS had higher levels of serum bilirubin, international normalized ratio, blood urea nitrogen, creatinine, and lower levels of albumin and platelets than those with normal mental status (NMS) (P = < 0.001). The most common cause of AMS was HE, accounting for nearly half of all patients. Other causes of AMS included the following: sepsis/infection (23%), metabolic disorders (8%), drugs/toxins (7%), structural lesions (5%), psychiatric disorders (1%), or multiple causes (8%). Mortality in patients with AMS was 35% compared to 16% in those with NMS (P < 0.0001). Patients with sepsis/infection, structural lesions, or multiple disorders causing AMS had the highest mortality (61%, 68%, and 79%, respectively). CONCLUSIONS: Nearly one third of admissions in cirrhotic patients were due to AMS, most commonly caused by HE. The overall mortality of patients admitted with AMS was greater than with NMS, particularly for those with infection or structural lesions, emphasizing the importance of a search for these causes of AMS in all patients with cirrhosis.

Rahimi RS; Elliott AC; Rockey DC

2013-04-01

25

Solid phase microextraction of volatile emissions of Ceratitis capitata (Wiedemann) (Diptera: Tephritidae): influence of fly sex, age, and mating status.  

UK PubMed Central (United Kingdom)

Considerable efforts have been devoted to understanding the courtship behavior and pheromone communication of medflies; however, the sex pheromone composition is still a controversial subject. The discovery of new components affecting medfly behavior would be of interest for medfly control methods based on semiochemicals. This work describes volatile compounds emitted by Ceratitis capitata collected using solid phase microextraction. The volatile study was conducted according to an experimental design with three factors (sex, age, and mating status) assumed to be relevant for better understanding the chemical communication. Emission data were treated by means of principal component analysis, a statistical methodology not previously applied to the study of volatiles emitted by fruit flies. The characterization of emission patterns could be useful for the selection of compounds to be further investigated in biological assays to improve knowledge of the key semiochemicals involved in medfly behavior.

Alfaro C; Vacas S; Zarzo M; Navarro-Llopis V; Primo J

2011-01-01

26

MOBILITY OF MASS-REARED DIAPAUSED AND NONDIAPAUSED CYDIA POMONELLA (LEPIDOPTERA: TORTRICIDAE): EFFECT OF MATING STATUS AND TREATMENT WITH GAMMA RADIATION  

Science.gov (United States)

Mass-reared insects may differ in their behavioral traits depending on whether or not they have undergone diapause. We studied the mobility of mass-reared diapaused and non-diapaused Cydia pomonella (L.) with a focus on understanding the effect of mating status and treatment with gamma radiation as...

27

Transposon-mediated alteration of TaMATE1B expression in wheat confers constitutive citrate efflux from root apices.  

UK PubMed Central (United Kingdom)

The TaMATE1B gene (for multidrug and toxic compound extrusion) from wheat (Triticum aestivum) was isolated and shown to encode a citrate transporter that is located on the plasma membrane. TaMATE1B expression in roots was induced by iron deficiency but not by phosphorus deficiency or aluminum treatment. The coding region of TaMATE1B was identical in a genotype showing citrate efflux from root apices (cv Carazinho) to one that lacked citrate efflux (cv Egret). However, sequence upstream of the coding region differed between these two genotypes in two ways. The first difference was a single-nucleotide polymorphism located approximately 2 kb upstream from the start codon in cv Egret. The second difference was an 11.1-kb transposon-like element located 25 bp upstream of the start codon in cv Carazinho that was absent from cv Egret. The influence of these polymorphisms on TaMATE1B expression was investigated using fusions to green fluorescent protein expressed in transgenic lines of rice (Oryza sativa). Fluorescence measurements in roots of rice indicated that 1.5- and 2.3-kb regions upstream of TaMATE1B in cv Carazinho (which incorporated 3' regions of the transposon-like element) generated 20-fold greater expression in the apical 1 mm of root compared with the native promoter in cv Egret. By contrast, fluorescence in more mature tissues was similar in both cultivars. The presence of the single-nucleotide polymorphism alone consistently generated 2-fold greater fluorescence than the cv Egret promoter. We conclude that the transposon-like element in cv Carazinho extends TaMATE1B expression to the root apex, where it confers citrate efflux and enhanced aluminum tolerance.

Tovkach A; Ryan PR; Richardson AE; Lewis DC; Rathjen TM; Ramesh S; Tyerman SD; Delhaize E

2013-02-01

28

Effect of diet and mating status on ovarian development and oviposition in the polyphagous predator Macrolophus caliginosus (Heteroptera: Miridae)  

UK PubMed Central (United Kingdom)

The mirid bug Macrolophus caliginosus is commercially reared on eggs of Ephestia kuehniella, constituting an effective but expensive factitious food. Artificial diets can decrease the rearing costs of this natural enemy, but developing and evaluating an artificial diet is a very time-consuming activity. In the current study, development and reproduction of M. caliginosus on two artificial diets based on egg yolk were investigated. The artificial diets resulted in longer development and lower adult weights, but survival was comparable with that of control insects fed E. kuehniella eggs. Reproductive potential of the predator reared on factitious and artificial foods was assessed using a dissection method. The influence of nymphal food on fecundity was less important than that of adult food. Adults fed E. kuehniella eggs had a preoviposition period of about 4 days, whereas adults offered only plant material started laying eggs about 7 days after emergence. Ovarian scores at day 7 were higher for females fed E. kuehniella eggs than for those given access only to a tobacco leaf. Ovarian scores were not significantly affected by mating status. In a final test, a parallel comparison of two methods for assessing reproductive response to diet was made. Here, adult couples were offered one of four diets: E. kuehniella eggs, one of two artificial diets or no food. Half of the females were dissected and the other half was held for determining lifetime oviposition. Females fed E. kuehniella eggs had superior ovarian scores and laid more eggs than those fed either artificial diet or those given no extra food. A good correlation (r = 0.97) was obtained between ovarian scores and oviposition data, indicating that dissecting females after 1 week provides a reliable estimate of fecundity as affected by diet quality. Rapid reproductive assessments as used in the current study will help to increase the rate of development of artificial diets and may contribute to more cost effective production methods for augmentative biological control agents.

Vandekerkhove B; Baal Evan; Bolckmans K; Clercq Pde

2006-12-01

29

Massive nest-box supplementation boosts fecundity, survival and even immigration without altering mating and reproductive behaviour in a rapidly recovered bird population.  

UK PubMed Central (United Kingdom)

Habitat restoration measures may result in artificially high breeding density, for instance when nest-boxes saturate the environment, which can negatively impact species' demography. Potential risks include changes in mating and reproductive behaviour such as increased extra-pair paternity, conspecific brood parasitism, and polygyny. Under particular cicumstances, these mechanisms may disrupt reproduction, with populations dragged into an extinction vortex. With the use of nuclear microsatellite markers, we investigated the occurrence of these potentially negative effects in a recovered population of a rare secondary cavity-nesting farmland bird of Central Europe, the hoopoe (Upupa epops). High intensity farming in the study area has resulted in a total eradication of cavity trees, depriving hoopoes from breeding sites. An intensive nest-box campaign rectified this problem, resulting in a spectacular population recovery within a few years only. There was some concern, however, that the new, high artificially-induced breeding density might alter hoopoe mating and reproductive behaviour. As the species underwent a serious demographic bottleneck in the 1970-1990s, we also used the microsatellite markers to reconstitute the demo-genetic history of the population, looking in particular for signs of genetic erosion. We found i) a low occurrence of extra-pair paternity, polygyny and conspecific brood parasitism, ii) a high level of neutral genetic diversity (mean number of alleles and expected heterozygosity per locus: 13.8 and 83%, respectively) and, iii) evidence for genetic connectivity through recent immigration of individuals from well differentiated populations. The recent increase in breeding density did thus not induce so far any noticeable detrimental changes in mating and reproductive behaviour. The demographic bottleneck undergone by the population in the 1970s-1990s was furthermore not accompanied by any significant drop in neutral genetic diversity. Finally, genetic data converged with a concomitant demographic study to evidence that immigration strongly contributed to local population recovery.

Berthier K; Leippert F; Fumagalli L; Arlettaz R

2012-01-01

30

Massive nest-box supplementation boosts fecundity, survival and even immigration without altering mating and reproductive behaviour in a rapidly recovered bird population.  

Science.gov (United States)

Habitat restoration measures may result in artificially high breeding density, for instance when nest-boxes saturate the environment, which can negatively impact species' demography. Potential risks include changes in mating and reproductive behaviour such as increased extra-pair paternity, conspecific brood parasitism, and polygyny. Under particular cicumstances, these mechanisms may disrupt reproduction, with populations dragged into an extinction vortex. With the use of nuclear microsatellite markers, we investigated the occurrence of these potentially negative effects in a recovered population of a rare secondary cavity-nesting farmland bird of Central Europe, the hoopoe (Upupa epops). High intensity farming in the study area has resulted in a total eradication of cavity trees, depriving hoopoes from breeding sites. An intensive nest-box campaign rectified this problem, resulting in a spectacular population recovery within a few years only. There was some concern, however, that the new, high artificially-induced breeding density might alter hoopoe mating and reproductive behaviour. As the species underwent a serious demographic bottleneck in the 1970-1990s, we also used the microsatellite markers to reconstitute the demo-genetic history of the population, looking in particular for signs of genetic erosion. We found i) a low occurrence of extra-pair paternity, polygyny and conspecific brood parasitism, ii) a high level of neutral genetic diversity (mean number of alleles and expected heterozygosity per locus: 13.8 and 83%, respectively) and, iii) evidence for genetic connectivity through recent immigration of individuals from well differentiated populations. The recent increase in breeding density did thus not induce so far any noticeable detrimental changes in mating and reproductive behaviour. The demographic bottleneck undergone by the population in the 1970s-1990s was furthermore not accompanied by any significant drop in neutral genetic diversity. Finally, genetic data converged with a concomitant demographic study to evidence that immigration strongly contributed to local population recovery. PMID:22545155

Berthier, Karine; Leippert, Fabio; Fumagalli, Luca; Arlettaz, Raphaël

2012-04-24

31

Status epilepticus alters hippocampal PKAbeta and PKAgamma expression in mice.  

UK PubMed Central (United Kingdom)

OBJECTIVES: To investigate the localization and progressive changes of cyclic-AMP dependent protein kinase (cPKA) in the mouse hippocampus at acute stages during and after pilocarpine induced status epilepticus. METHODS: Pilocarpine induced status epilepticus mice were sacrificed 30 min, 2 h or 1 day after the start of a approximately 7 h lasting status as assessed by video-electroencephalography. Brains were processed for quantitative immunohistochemistry of hippocampal cPKAbeta and cPKAgamma, and immunohistochemical co-localization of cPKAbeta and cPKAgamma with calbindin (CB), calretinin (CR), and parvalbumin (PV). RESULTS: Based on anatomical and morphological assessment, cPKAbeta was primarily expressed by principal cells and cPKAgamma by interneurons. In CA1, cPKAbeta co-localized with 76% of CB, 41% of CR, and 95% of PV-immunopositive cells, while cPKAgamma co-localized with 50% of CB, 29% of CR, and 80% of PV-immunopositive cells. Upon induction of status epilepticus, cPKAbeta expression was transiently reduced in CA1, whereas cPKAgamma expression was sustainably reduced. CONCLUSION: cPKA may play an important role in neuronal hyperexcitability, death and epileptogenesis during and after pilocarpine induced status epilepticus.

Liu JX; Tang YC; Liu Y; Tang FR

2010-09-01

32

Preliminary study on factors influencing rabbit doe reproductive efficiency: Effect of parity, day of mating, and suckling on ovarian status and estrogen levels at day 6 of pregnancy.  

UK PubMed Central (United Kingdom)

The rabbit corpus luteum becomes an estradiol-dependent tissue by day 6 of gestation, and adequate estrogen is critical to avoid pregnancy failure. The aim of this study was to investigate the effect of parity (primiparous or multiparous), day of mating (11 or 21 d postpartum), and suckling status (suckling or nonsuckling) on various reproductive traits in hybrid rabbit does (n = 96). Ovarian structures on day 6 after coitus were evaluated by means of ultrasonography. Blood samples were collected that day, and the serum was analyzed for estradiol-17? by radioimmunoassay (RIA). Parity and suckling had significant effects on mating rate (P < 0.01 and P < 0.05, respectively). More does accepted the male on day 11 than on day 21 (P < 0.05). Ovulation frequency was significantly affected by parity (P < 0.05), day of mating (P < 0.01), and suckling (P < 0.01). Fewer ovarian large follicles and lower estradiol-17? levels were detected in suckling compared with nonsuckling rabbits (P < 0.01). Since estrogen concentrations are commonly used to assess follicular growth and steroidogenic capacity, the lower hormonal levels in the suckling rabbits may reveal poorer ovarian activity, which could result in reduced reproductive efficiency. Our observations confirm the existence of a partial antagonism between lactation and reproduction in rabbits. Further research is needed to elucidate these phenomena, including when artificial insemination is done. Ultrasonography could represent a noninvasive and reliable method for studying several reproductive functions and dysfunctions in rabbits.

Marongiu ML; Dimauro C

2013-04-01

33

MATING STATUS AND CHOICE OF GROU0P SIZE IN THE PHORETIC FLY NORRBOMIA FRIGIPENNIS (SPULER) (DIPTERA: SPHAEROCERIDAE)  

Science.gov (United States)

The fly Norrbomia frigipennis (Sphaeroceridae) is a phoretic kleptoparasite. The insects mate on scarab dung beetles, follow them underground and lay their eggs in the feces collected by the beetles. Numbers of flies on the beetles varies from one to ca. twenty. In the field larger and smaller group...

34

Is the Oxidant/Antioxidant Status Altered in CADASIL Patients?  

Science.gov (United States)

The altered aggregation of proteins in non-native conformation is associated with endoplasmic reticulum derangements, mitochondrial dysfunction and excessive production of reactive oxygen species. Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a rare hereditary systemic vasculopathy, caused by NOTCH3 mutations within the receptor extracellular domain, that lead to abnormal accumulation of the mutated protein in the vascular wall. NOTCH3 misfolding could cause free radicals increase also in CADASIL. Aim of the study was to verify whether CADASIL patients have increased oxidative stress compared to unrelated healthy controls. We enrolled 15 CADASIL patients and 16 gender- and age-matched healthy controls with comparable cardiovascular risk factor. Blood and plasma reduced and total aminothiols (homocysteine, cysteine, glutathione, cysteinylglycine) were measured by HPLC and plasma 3-nitrotyrosine by ELISA. Only plasma reduced cysteine (Pr-Cys) and blood reduced glutathione (Br-GSH) concentrations differed between groups: in CADASIL patients Br-GSH levels were higher (p = 0.019) and Pr-Cys lower (p = 0.010) than in controls. No correlation was found between Br-GSH and Pr-Cys either in CADASIL patients (rho 0.25, P=0.36) or in controls (rho -0.15, P=0.44). Conversely, 3-nitrotyrosine values were similar in CADASIL and healthy subjects (p = 0.82). The high levels of antioxidant molecules and low levels of oxidant mediators found in our CADASIL population might either be expression of an effective protective action against free radical formation at an early stage of clinical symptoms or they could suggest that oxidative stress is not directly involved in the pathogenesis of CADASIL.

Campolo, Jonica; De Maria, Renata; Mariotti, Caterina; Tomasello, Chiara; Parolini, Marina; Frontali, Marina; Inzitari, Domenico; Valenti, Raffaella; Federico, Antonio; Taroni, Franco; Parodi, Oberdan

2013-01-01

35

Is the oxidant/antioxidant status altered in CADASIL patients?  

UK PubMed Central (United Kingdom)

The altered aggregation of proteins in non-native conformation is associated with endoplasmic reticulum derangements, mitochondrial dysfunction and excessive production of reactive oxygen species. Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a rare hereditary systemic vasculopathy, caused by NOTCH3 mutations within the receptor extracellular domain, that lead to abnormal accumulation of the mutated protein in the vascular wall. NOTCH3 misfolding could cause free radicals increase also in CADASIL. Aim of the study was to verify whether CADASIL patients have increased oxidative stress compared to unrelated healthy controls. We enrolled 15 CADASIL patients and 16 gender- and age-matched healthy controls with comparable cardiovascular risk factor. Blood and plasma reduced and total aminothiols (homocysteine, cysteine, glutathione, cysteinylglycine) were measured by HPLC and plasma 3-nitrotyrosine by ELISA. Only plasma reduced cysteine (Pr-Cys) and blood reduced glutathione (Br-GSH) concentrations differed between groups: in CADASIL patients Br-GSH levels were higher (p = 0.019) and Pr-Cys lower (p = 0.010) than in controls. No correlation was found between Br-GSH and Pr-Cys either in CADASIL patients (rho 0.25, P = 0.36) or in controls (rho -0.15, P = 0.44). Conversely, 3-nitrotyrosine values were similar in CADASIL and healthy subjects (p = 0.82). The high levels of antioxidant molecules and low levels of oxidant mediators found in our CADASIL population might either be expression of an effective protective action against free radical formation at an early stage of clinical symptoms or they could suggest that oxidative stress is not directly involved in the pathogenesis of CADASIL.

Campolo J; De Maria R; Mariotti C; Tomasello C; Parolini M; Frontali M; Inzitari D; Valenti R; Federico A; Taroni F; Parodi O

2013-01-01

36

Is the oxidant/antioxidant status altered in CADASIL patients?  

Science.gov (United States)

The altered aggregation of proteins in non-native conformation is associated with endoplasmic reticulum derangements, mitochondrial dysfunction and excessive production of reactive oxygen species. Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a rare hereditary systemic vasculopathy, caused by NOTCH3 mutations within the receptor extracellular domain, that lead to abnormal accumulation of the mutated protein in the vascular wall. NOTCH3 misfolding could cause free radicals increase also in CADASIL. Aim of the study was to verify whether CADASIL patients have increased oxidative stress compared to unrelated healthy controls. We enrolled 15 CADASIL patients and 16 gender- and age-matched healthy controls with comparable cardiovascular risk factor. Blood and plasma reduced and total aminothiols (homocysteine, cysteine, glutathione, cysteinylglycine) were measured by HPLC and plasma 3-nitrotyrosine by ELISA. Only plasma reduced cysteine (Pr-Cys) and blood reduced glutathione (Br-GSH) concentrations differed between groups: in CADASIL patients Br-GSH levels were higher (p = 0.019) and Pr-Cys lower (p = 0.010) than in controls. No correlation was found between Br-GSH and Pr-Cys either in CADASIL patients (rho 0.25, P = 0.36) or in controls (rho -0.15, P = 0.44). Conversely, 3-nitrotyrosine values were similar in CADASIL and healthy subjects (p = 0.82). The high levels of antioxidant molecules and low levels of oxidant mediators found in our CADASIL population might either be expression of an effective protective action against free radical formation at an early stage of clinical symptoms or they could suggest that oxidative stress is not directly involved in the pathogenesis of CADASIL. PMID:23799141

Campolo, Jonica; De Maria, Renata; Mariotti, Caterina; Tomasello, Chiara; Parolini, Marina; Frontali, Marina; Inzitari, Domenico; Valenti, Raffaella; Federico, Antonio; Taroni, Franco; Parodi, Oberdan

2013-06-14

37

Mate Preferences Do Predict Attraction and Choices in the Early Stages of Mate Selection.  

UK PubMed Central (United Kingdom)

Although mate preference research has firmly established that men value physical attractiveness more than women do and women value social status more than men do, recent speed-dating studies have indicated mixed evidence (at best) for whether people's sex-differentiated mate preferences predict actual mate choices. According to an evolutionary, mate preference priority model (Li, Bailey, Kenrick, & Linsenmeier, 2002; Li & Kenrick, 2006; Li, Valentine, & Patel, 2011), the sexes are largely similar in what they ideally like, but for long-term mates, they should differ on what they most want to avoid in early selection contexts. Following this model, we conducted experiments using online messaging and modified speed-dating platforms. Results indicate that when a mating pool includes people at the low end of social status and physical attractiveness, mate choice criteria are sex-differentiated: Men, more than women, chose mates based on physical attractiveness, whereas women, more than men, chose mates based on social status. In addition, individuals who more greatly valued social status or physical attractiveness on paper valued these traits more in their actual choices. In particular, mate choices were sex-differentiated when considering long-term relationships but not short-term ones, where both sexes shunned partners with low physical attractiveness. The findings validate a large body of mate preferences research and an evolutionary perspective on mating, and they have implications for research using speed-dating and other interactive contexts. (PsycINFO Database Record (c) 2013 APA, all rights reserved).

Li NP; Yong JC; Tov W; Sng O; Fletcher GJ; Valentine KA; Jiang YF; Balliet D

2013-08-01

38

Strategies of Human Mating  

Directory of Open Access Journals (Sweden)

Full Text Available Modern humans have inherited the mating strategies that led to the success of their ancestors. These strategies include long-term mating, short-term mating, extra-pair mating, mate poaching, and mate guarding. This article presents empirical evidence supporting evolution-based hypotheses about the complexities of these mating strategies. Since men and women historically confronted different adaptive problems in the mating domain, the sexes differ profoundly in evolved strategic solutions. These differences include possessing different mate preferences, different desires for short-term mating, and differences in the triggers that evoke sexual jealousy. The study of human mating is one of the “success stories” of evolutionary psychology.

David M. Buss

2006-01-01

39

Mower mate  

UK PubMed Central (United Kingdom)

Is a combination Tool Kit and Lawn Care Product Containment Devise which is strapped over and on top of a Riding Lawn Mower Motor Housing. The Mower Mate will allow for frequently used tools and lawn care products to be kept with the Riding Lawn Mower and application of Lawn Care Products while mowing.

BLAIR MATTHEW SEAN

40

Highly efficient generation of transgenic sheep by lentivirus accompanying the alteration of methylation status.  

UK PubMed Central (United Kingdom)

BACKGROUND: Low efficiency of gene transfer and silence of transgene expression are the critical factors hampering the development of transgenic livestock. Recently, transfer of recombinant lentivirus has been demonstrated to be an efficient transgene delivery method in various animals. However, the lentiviral transgenesis and the methylation status of transgene in sheep have not been well addressed. METHODOLOGY/PRINCIPLE FINDINGS: EGFP transgenic sheep were generated by injecting recombinant lentivirus into zygotes. Of the 13 lambs born, 8 carried the EGFP transgene, and its chromosomal integration was identified in all tested tissues. Western blotting showed that GFP was expressed in all transgenic founders and their various tissues. Analysis of CpG methylation status of CMV promoter by bisulfate sequencing unraveled remarkable variation of methylation levels in transgenic sheep. The average methylation levels ranged from 37.6% to 79.1% in the transgenic individuals and 34.7% to 83% in the tested tissues. Correlative analysis of methylation status with GFP expression revealed that the GFP expression level was inversely correlated with methylation density. The similar phenomenon was also observed in tested tissues. Transgene integration determined by Southern blotting presented multiple integrants ranging from 2 to 6 copies in the genome of transgenic sheep. CONCLUSIONS/SIGNIFICANCE: Injection of lentiviral transgene into zygotes could be a promising efficient gene delivery system to generate transgenic sheep and achieved widespread transgene expression. The promoter of integrants transferred by lentiviral vector was subjected to dramatic alteration of methylation status and the transgene expression level was inversely correlative with promoter methylation density. Our work illustrated for the first time that generation of transgenic sheep by injecting recombinant lentivirus into zygote could be an efficient tool to improve sheep performance by genetic modification.

Liu C; Wang L; Li W; Zhang X; Tian Y; Zhang N; He S; Chen T; Huang J; Liu M

2013-01-01

 
 
 
 
41

Parasite-augmented mate choice and reduction in innate fear in rats infected by Toxoplasma gondii.  

UK PubMed Central (United Kingdom)

Typically, female rats demonstrate clear mate choice. Mate preference is driven by the evolutionary need to choose males with heritable parasite resistance and to prevent the transmission of contagious diseases during mating. Thus, females detect and avoid parasitized males. Over evolutionary time scales, parasite-free males plausibly evolve to advertise their status. This arrangement between males and females is obviously detrimental to parasites, especially for sexually transmitted parasites. Yet Toxoplasma gondii, a sexually transmitted parasite, gets around this obstacle by manipulating mate choice of uninfected females. Males infected with this parasite become more attractive to uninfected females. The ability of T. gondii to not only advantageously alter the behavior and physiology of its host but also secondarily alter the behavior of uninfected females presents a striking example of the 'extended phenotype' of parasites. Toxoplasma gondii also abolishes the innate fear response of rats to cat odor; this likely increases parasite transmission through the trophic route. It is plausible that these two manipulations are not two distinct phenotypes, but are rather part of a single pattern built around testosterone-mediated interplay between mate choice, parasitism and predation.

Vyas A

2013-01-01

42

Electroencephalographic findings in consecutive emergency department patients with altered mental status: a preliminary report.  

UK PubMed Central (United Kingdom)

Electroencephalography (EEG) can help narrow the differential diagnosis of altered mental status (AMS) and is necessary to diagnose nonconvulsive seizure (NCS). The objective of this prospective observational study is to identify the prevalence of EEG abnormalities in emergency department patients with AMS. Patients of at least 13 years of age with AMS were enrolled, whereas those with an easily identifiable cause (e.g. hypoglycemia) underlying their AMS were excluded. Easily identifiable cause of AMS (e.g. hypoglycemia). A 30-min EEG with the standard 19 electrodes was performed on each patient. Descriptive statistics (%, 95% confidence interval) are used to report EEG findings of the first 50 enrolled patients. Thirty-five EEGs (70%, 57-81%) were abnormal. The most common abnormality was slowing of background activities (46%, 33-60%), reflecting an underlying encephalopathy. NCS was diagnosed in three (6%, 1-17%), including one patient in nonconvulsive status epilepticus. Nine patients (18%, 10-31%) had interictal epileptiform abnormalities, indicating an increased risk of spontaneous seizure. Patients presenting to the emergency department with AMS have a high prevalence of EEG abnormalities, including NCS.

Zehtabchi S; Abdel Baki SG; Grant AC

2013-04-01

43

Formerly Obese, Now Thin and Confused: The Utility of Mnemonics in the Approach to Altered Mental Status.  

UK PubMed Central (United Kingdom)

: Altered mental status represents a common cause for admission to general medicine services. Often a significant workup ensues to define an underlying etiology. When a history of bariatric surgery with small bowel resection precedes the presentation, the differential diagnosis expands. We review a patient, having prior bariatric surgery and small bowel resection, who presents with altered mental status. After an extensive workup, she was diagnosed with a rare clinical problem, D-lactic acidosis. In presenting this case, we examine the use of mnemonics in medicine and how this can assist in solving clinical problems.

Burski CM; Miller CS; Centor RM

2013-04-01

44

Life history parameters and scale-cover surface area of Aonidiella aurantii are altered in a mating disruption environment: implications for biological control.  

UK PubMed Central (United Kingdom)

BACKGROUND: In recent years, environmentally safe measures to control the California red scale (CRS), Aonidiella aurantii (Maskell), have been successfully implemented. These measures include mating disruption (MD) and biological control. The goal of this study was to examine the effect of high concentrations of the CRS sex pheromone on its life history parameters and scale-cover surface area under controlled laboratory conditions. RESULTS: The developmental time of both males and females of CRS increased with exposure to airborne pheromone. MD had an effect on both the total number of progeny and on the crawler production period for females. Accordingly, demographic parameters such as net fecundity (R(0) ) and intrinsic rate of increase (r(m) ) were significantly lower in the pheromone-treated populations. The largest scale-cover surface areas were observed in the CRS reared in the pheromone environment. CONCLUSION: A clear influence of airborne pheromone on the biology of CRS has been demonstrated. In addition to the classical mating disruption benefits of this technique, additional benefits, such as increase in the duration of exposure to natural enemies and increase in size, which benefits some species of parasitoids, have been confirmed.

Vanaclocha P; Vacas S; Alfaro C; Primo J; Verdú MJ; Navarro-Llopis V; Urbaneja A

2012-07-01

45

Mate recognition in fungi.  

UK PubMed Central (United Kingdom)

The ascomycete and basidiomycete fungi have contributed much to our understanding of eukaryotic cell biology. The study of mate recognition, in particular, has provided detailed understanding of cell signalling pathways and cell-specific gene transcription. Sexual dimorphism has little relevance to mating in these organisms, indeed specialised cells for mating are found only in filamentous ascomycetes and even here, a single individual produces both male and female structures. None the less, most species have genetic barriers to prevent selfing. The genes that determine self-incompatibility divide populations into different mating types, and only individuals with different mating types can engage in sexual reproduction. Ascomycetes have just two mating types, but basidiomycetes may have several thousands. Despite apparent differences in the biology and numbers of mating types in these fungi, it is becoming increasingly apparent that many components of their mating pathways are highly conserved.

Casselton LA

2002-02-01

46

Mating-induced reduction in accessory reproductive organ size in the stalk-eyed fly Cyrtodiopsis dalmanni  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Internal reproductive organ size is an important determinant of male reproductive success. While the response of testis length to variation in the intensity of sperm competition is well documented across many taxa, few studies address the importance of testis size in determining other components of male reproductive success (such as mating frequency) or the significance of size variation in accessory reproductive organs. Accessory gland length, but not testis length, is both phenotypically and genetically correlated with male mating frequency in the stalk-eyed fly Cyrtodiopsis dalmanni. Here we directly manipulate male mating status to investigate the effect of copulation on the size of both the testes and the accessory glands of C. dalmanni. Results Accessory gland length was positively correlated with male mating frequency. Copulation induced a significant decrease in accessory gland size. The size of the accessory glands then recovered slowly over the next 8–48 hours. Neither testis length nor testis area was altered by copulation. Conclusion These results reveal that the time course of accessory gland recovery corresponds to field observations of mating behaviour and suggest that accessory gland size may limit male mating frequency in C. dalmanni.

Rogers David W; Chapman Tracey; Fowler Kevin; Pomiankowski Andrew

2005-01-01

47

Increased oxidative stress and altered antioxidants status in patients with chronic allergic rhinitis  

Directory of Open Access Journals (Sweden)

Full Text Available Background: Allergic rhinitis is an inflammatory disorder of the upper airways. Although several oxidants and antioxidants are likely to be involved, alterations in only limited parameters have been studied. Objective: In this study an attempt has been made to study the oxidant-antioxidant imbalance by investigating changes in a wide range of oxidants and antioxidants in the blood. Methods: Blood samples were obtained from 39 chronic allergic rhinitis patients (males 24, females 15), aged 20-70 (mean age 36.33 ± 2.03) years and 53 individuals (36 males, 17 females); aged 24 to 64 (mean age 45.42 ± 1.36) years. Duration of allergic rhinitis was 1.77 ± 0.237 years. In the study group, nasal symptoms were scored and the results were recorded. The patients were classified as having perennial Allergic rhinitis (PAR) if they had had at least 2 rhinitis symptoms (sneezing, rhinorrhea, nasal obstruction, itching) for at least 6 months a year in the previous 2 years and if they had a positive skin prick test response to at least 1 clinically significant perennial allergen (e.g., house dust mites, molds, cockroach, cockroach excrement grass and tree pollen, cat and dog epithelia and molds, or animal dander). They had no other allergic diseases except persistent allergic rhinitis diagnosed by the physical and history examination. Erythrocyte lipid peroxidation, erythrocyte antioxidants viz., glutathione, glutathione reductase, superoxide dismutase, catalase and plasma antioxidants viz., ceruloplasmin, glutathione-S-transferase, vitamin C, total antioxidant activity were estimated in the above two groups. Results: Erythrocyte lipid peroxidation (0 hour, p < 0.01) and superoxide dismutase (p < 0.01) were significantly higher, whereas plasma vitamin C (p < 0.001), ceruloplasmin (p < 0.05) and total antioxidant activity (p < 0.001) were significantly lower in chronic allergic rhinitis patients when compared to controls. Plasma Glutathione S transferase and erythrocyte catalase, glutathione, and glutathione reductase remained unchanged from normal subjects. Conclusion: The changes in different parameters indicate an imbalance in the oxidant and antioxidant status in chronic allergic rhinitis patients. Further studies are required to investigate the potential for antioxidant supplements to be used as routine therapy in chronic allergic rhinitis patients. Capsule summery: The study shows that the body is trying to cope for the oxidative stress by altering the enzyme levels. But external supplement may also be required as the total antioxidant levels are very much depleted.

Shiefa Sequeira; Ashalatha V. Rao; Anjali Rao

2012-01-01

48

Accuracy of the initial diagnosis among patients with an acutely altered mental status.  

UK PubMed Central (United Kingdom)

OBJECTIVES: The objectives of this prospective observational study were to: (1) determine the accuracy of physician diagnosis in patients with an acutely altered mental status (AMS) within the first 20 min of emergency department (ED) presentation; and (2) access if physician confidence in early diagnosis correlates with accuracy of diagnosis. METHODS: A prospective observational convenience study was conducted of 112 adult patients who presented to an urban county ED with AMS (Glasgow Coma Scale (GCS) score ?14) between August 2008 and July 2009. Within the first 20 min of patient presentation to the ED, treating physicians were asked to record their best diagnostic guess of the cause of the patient's AMS and their confidence in this diagnosis. Serial hourly GCS was performed and the results of all diagnostic testing were recorded. Blinded investigators determined the final consensus diagnostic cause of the patient's AMS. RESULTS: The final consensus diagnoses for AMS aetiologies were as follows: isolated alcohol intoxication 31%, other (psychotic episodes, underlying dementia) 21%, combination alcohol/other drug intoxications 18%, isolated other drug intoxications 10%, other metabolic derangements 6%, cerebrovascular accident/transient ischaemic attack 4%, seizures/post-ictal states 4%, traumatic brain injuries 3%, isolated opiate intoxications 2%, isolated benzodiazepine intoxication 1% and septic episode 1%. The emergency physician's initial diagnosis of the AMS patient correlated with the accuracy of the final diagnosis (r(2)=0.807). The quintiles of confidence of diagnosis were: 0-20% degree of confidence had a 33% diagnostic accuracy, 21-40% had 25% accuracy, 41-60% had 43% accuracy, 61-80% had 52% accuracy and those with 81-100% confidence of initial diagnosis had 78% accuracy. Of the 106 patients with an initial diagnosis, 52 (51%) had a head CT performed, with eight (8%) having an acute abnormality. DISCUSSION: Early diagnoses of AMS patients are moderately accurate. Few early misdiagnoses of AMS patients were clinically relevant. Physicians' greater degree of confidence in their diagnosis correlated with greater accuracy.

Sporer KA; Solares M; Durant EJ; Wang W; Wu AH; Rodriguez RM

2013-03-01

49

Distribution of mating type alleles and fertility status of Magnaporthe grisea causing gray leaf spot of perennial ryegrass and St. Augustinegrass turf.  

UK PubMed Central (United Kingdom)

Isolates of Magnaporthe grisea causing gray leaf spot of perennial ryegrass (PR) (Lolium perenne) and St. Augustinegrass (SA) (Stenotaphrum secundatum) were analyzed for mating compatibility and fertility. A total of 312 isolates of M. grisea from PR and 62 isolates from SA were paired with hermaphroditic tester strains from finger millet (Eleusine coracana), rice (Oryza sativa), and wheat (Triticum aestivum). All the PR isolates belonged to a single mating type, MAT1-2. Male fertility was observed in all these isolates. Asci and ascospores were not produced regardless of their developmental stage. Of the 139 (44.6%) isolates from PR that formed perithecia with the fertile tester strains, 83 (59.7%) were highly fertile, 33 (23.7%) were intermediately fertile, and 23 (16.5%) were low in fertility. Both mating types were observed among the isolates of SA, where MAT1-1 predominated the MAT1-2 type. An equal number of male and female fertile isolates were detected among these isolates obtained from a single location; however, none of the isolates behaved as hermaphrodites. Few ascospores were produced in crosses between two isolates of SA and a finger millet tester. Of the 62 monoconidial isolates of SA tested, 19 (30.6%) isolates formed perithecia, of which 5 (26.3%) were highly fertile, 7 (36.8%) were intermediately fertile, 7 (36.8%) were low in fertility, and 43 (69.4%) were infertile. The results of this study indicate that the sexual stage may not be a significant factor contributing to the genetic variation the gray leaf spot pathogen population.

Viji G; Uddin W

2002-08-01

50

Teaching medical students a clinical approach to altered mental status: simulation enhances traditional curriculum  

Directory of Open Access Journals (Sweden)

Full Text Available Introduction: Simulation-based medical education (SBME) is increasingly being utilized for teaching clinical skills in undergraduate medical education. Studies have evaluated the impact of adding SBME to third- and fourth-year curriculum; however, very little research has assessed its efficacy for teaching clinical skills in pre-clerkship coursework. To measure the impact of a simulation exercise during a pre-clinical curriculum, a simulation session was added to a pre-clerkship course at our medical school where the clinical approach to altered mental status (AMS) is traditionally taught using a lecture and an interactive case-based session in a small group format. The objective was to measure simulation's impact on students’ knowledge acquisition, comfort, and perceived competence with regards to the AMS patient. Methods: AMS simulation exercises were added to the lecture and small group case sessions in June 2010 and 2011. Simulation sessions consisted of two clinical cases using a high-fidelity full-body simulator followed by a faculty debriefing after each case. Student participation in a simulation session was voluntary. Students who did and did not participate in a simulation session completed a post-test to assess knowledge and a survey to understand comfort and perceived competence in their approach to AMS. Results: A total of 154 students completed the post-test and survey and 65 (42%) attended a simulation session. Post-test scores were higher in students who attended a simulation session compared to those who did not (p<0.001). Students who participated in a simulation session were more comfortable in their overall approach to treating AMS patients (p=0.05). They were also more likely to state that they could articulate a differential diagnosis (p=0.03), know what initial diagnostic tests are needed (p=0.01), and understand what interventions are useful in the first few minutes (p=0.003). Students who participated in a simulation session were more likely to find the overall AMS curriculum useful (p<0.001). Conclusion: Students who participated in a simulation exercise performed better on a knowledge-based test and reported increased comfort and perceived competence in their clinical approach to AMS. SBME shows significant promise for teaching clinical skills to medical students during pre-clinical curriculum.

Jeremy D. Sperling; Sunday Clark; Yoon Kang

2013-01-01

51

Teaching medical students a clinical approach to altered mental status: simulation enhances traditional curriculum.  

UK PubMed Central (United Kingdom)

INTRODUCTION: Simulation-based medical education (SBME) is increasingly being utilized for teaching clinical skills in undergraduate medical education. Studies have evaluated the impact of adding SBME to third- and fourth-year curriculum; however, very little research has assessed its efficacy for teaching clinical skills in pre-clerkship coursework. To measure the impact of a simulation exercise during a pre-clinical curriculum, a simulation session was added to a pre-clerkship course at our medical school where the clinical approach to altered mental status (AMS) is traditionally taught using a lecture and an interactive case-based session in a small group format. The objective was to measure simulation's impact on students' knowledge acquisition, comfort, and perceived competence with regards to the AMS patient. METHODS: AMS simulation exercises were added to the lecture and small group case sessions in June 2010 and 2011. Simulation sessions consisted of two clinical cases using a high-fidelity full-body simulator followed by a faculty debriefing after each case. Student participation in a simulation session was voluntary. Students who did and did not participate in a simulation session completed a post-test to assess knowledge and a survey to understand comfort and perceived competence in their approach to AMS. RESULTS: A total of 154 students completed the post-test and survey and 65 (42%) attended a simulation session. Post-test scores were higher in students who attended a simulation session compared to those who did not (p<0.001). Students who participated in a simulation session were more comfortable in their overall approach to treating AMS patients (p=0.05). They were also more likely to state that they could articulate a differential diagnosis (p=0.03), know what initial diagnostic tests are needed (p=0.01), and understand what interventions are useful in the first few minutes (p=0.003). Students who participated in a simulation session were more likely to find the overall AMS curriculum useful (p<0.001). CONCLUSION: Students who participated in a simulation exercise performed better on a knowledge-based test and reported increased comfort and perceived competence in their clinical approach to AMS. SBME shows significant promise for teaching clinical skills to medical students during pre-clinical curriculum.

Sperling JD; Clark S; Kang Y

2013-01-01

52

Male scorpionflies assess the amount of rival sperm transferred by females' previous mates  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Theory predicts that when sperm compete numerically, selection will favor males who vary the number of sperm they transfer with the immediate level of sperm competition. In this study, I measured male mating investment in response to both female mating status (virgin vs. mated) and the number of for...

Engqvist, Leif

53

Alterations in hyperpolarization-activated cyclic nucleotidegated cation channel (HCN) expression in the hippocampus following pilocarpine-induced status epilepticus  

Directory of Open Access Journals (Sweden)

Full Text Available To understand the effects of HCN as potential mediators in thepathogenesis of epilepsy that evoke long-term impairedexcitability; the present study was designed to elucidate whetherthe alterations of HCN expression induced by status epilepticus(SE) is responsible for epileptogenesis. Although HCN1 immunoreactivitywas observed in the hippocampus, its immunoreactivitieswere enhanced at 12 hrs following SE. Although, HCN1immunoreactivities were reduced in all the hippocampi at 2weeks, a re-increase in the expression at 2-3 months followingSE was observed. In contrast to HCN1, HCN 4 expressions wereun-changed, although HCN2 immunoreactive neurons exhibitedsome changes following SE. Taken together, our findings suggestthat altered expressions of HCN1 following SE may be mainlyinvolved in the imbalances of neurotransmissions to hippocampalcircuits; thus, it is proposed that HCN1 may play animportant role in the epileptogenic period as a compensatoryresponse.

Yun-Jung Oh, Jongju Na, Ji-Heon Jeong, Dae-Kyoon Park, Kyung-Ho Park, Jeong-Sik Ko & Duk-Soo Kim*

2012-01-01

54

Lacosamide treatment following status epilepticus attenuates neuronal cell loss and alterations in hippocampal neurogenesis in a rat electrical status epilepticus model.  

UK PubMed Central (United Kingdom)

PURPOSE: The antiepileptic drug, lacosamide, exerts its therapeutic activity by enhancing slow inactivation of voltage-gated sodium channels. Because putative preventive or disease-modifying effects of drugs may affect epileptogenesis, intrinsic severity, and comorbidities, it is of particular interest to assess the effect of lacosamide on the development of epilepsy and associated cellular alterations. METHODS: The effect of lacosamide was evaluated in an electrical rat status epilepticus (SE) model with a 24-day treatment phase following induction of SE. The impact of lacosamide on the development of spontaneous seizures based on continuous video-electroencephalography (EEG) monitoring, as well as the impact on neuronal cell loss and alterations in hippocampal neurogenesis, was assessed. KEY FINDINGS: Neither low-dose nor high-dose lacosamide affected the development of spontaneous seizures. A dose-dependent neuroprotective effect of lacosamide with significant reduction of neuronal cell loss was observed in the hippocampal CA1 region, as well as in the piriform cortex. In addition, lacosamide attenuated the impact of SE on the rate of hippocampal cell neurogenesis. Moreover, lacosamide prevented a significant rise in the number of persistent basal dendrites. SIGNIFICANCE: Our data do not support an antiepileptogenic effect of lacosamide. However, because lacosamide reduced SE-associated cellular alterations, it would be of interest to determine whether these effects indicate a putative disease-modifying effect of lacosamide in future studies.

Licko T; Seeger N; Zellinger C; Russmann V; Matagne A; Potschka H

2013-07-01

55

Mating behaviour and mating competitiveness of radiation sterilized males of Dysdercus koenigii Fabricius  

International Nuclear Information System (INIS)

In Dysdercus koenigii F., while, the females were ready for mating soon after emergence, the males attained sexual maturity only after 36-48 h. Irradiation of males with a sterilizing dose of 70 Gy of x rays prior to attaining sexual maturity brought about delay in mating. Irradiation after attaining sexual maturity did not however, alter mating behaviour. Evaluation of mating competitiveness of sterile males by confining a normal female with sterile and normal males in 1:1 or 2:1 ratio and then recording the type of matings that occurred revealed that 1) mating competitiveness of males rendered sterile by irradiating prior to attaining maturity was greatly reduced even when the sterile males were aged for 48 hrs 2) when males were irradiated after attaining maturity, they significantly out numbered the normal males in mating with females, apparently indicating their becoming more vigorous than normal males. Irradiation during early 5th instar induced wing deformities. Such males having wing deformities failed to undergo copulation with normal females, but wing deformity among females did not prevent them from undergoing copulation with normal males. (author). 11 refs., 3 tabs.

1995-01-01

56

Fish oil supplement alters markers of inflammatory and nutritional status in colorectal cancer patients.  

Science.gov (United States)

Inflammation is a common feature in cancer. The presence and magnitude of the chronic systemic inflammatory responses may produce progressive nutritional decline. This study aims at investigating whether there are changes in inflammation markers and/or in nutritional status of patients with colorectal cancer undergoing chemotherapy who were supplemented with fish oil. The clinical trial was conducted with 23 patients randomly distributed in 2 groups. The supplemented group (SG) consumed 2 g of fish oil containing 600 milligrams of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) for 9 wk. Nutritional and inflammatory markers status was available, both at a baseline (M0), and after 9 wk of chemotherapy (M9) in the SG and in the nonsupplemented group (NSG). Statistical analysis was conducted with STATA 11.0 software. SG and NSG presented the same baseline characteristics (P > 0.05). Nutritional status indicators such as body mass index and body weight were modified only in the NSG when comparing baseline and M9, P = 0.03 and P = 0.01 respectively, whereas in SG these indicators did not vary. Patients supplemented with fish oil (SG) showed a clinically relevant decrease in the C-reactive protein/albumin relation (P = 0.005). Low doses of fish oil supplement can positively modulate the nutritional status and the C-reative protein/albumin ratio. PMID:22295891

Silva, Juliana de Aguiar Pastore; Trindade, Erasmo Benício Santos de Moraes; Fabre, Maria Emilia de Souza; Menegotto, Vicente Martorano; Gevaerd, Sheila; Buss, Ziliane da Silva; Frode, Tânia Silvia

2012-02-01

57

Fish oil supplement alters markers of inflammatory and nutritional status in colorectal cancer patients.  

UK PubMed Central (United Kingdom)

Inflammation is a common feature in cancer. The presence and magnitude of the chronic systemic inflammatory responses may produce progressive nutritional decline. This study aims at investigating whether there are changes in inflammation markers and/or in nutritional status of patients with colorectal cancer undergoing chemotherapy who were supplemented with fish oil. The clinical trial was conducted with 23 patients randomly distributed in 2 groups. The supplemented group (SG) consumed 2 g of fish oil containing 600 milligrams of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) for 9 wk. Nutritional and inflammatory markers status was available, both at a baseline (M0), and after 9 wk of chemotherapy (M9) in the SG and in the nonsupplemented group (NSG). Statistical analysis was conducted with STATA 11.0 software. SG and NSG presented the same baseline characteristics (P > 0.05). Nutritional status indicators such as body mass index and body weight were modified only in the NSG when comparing baseline and M9, P = 0.03 and P = 0.01 respectively, whereas in SG these indicators did not vary. Patients supplemented with fish oil (SG) showed a clinically relevant decrease in the C-reactive protein/albumin relation (P = 0.005). Low doses of fish oil supplement can positively modulate the nutritional status and the C-reative protein/albumin ratio.

Silva Jde A; Trindade EB; Fabre ME; Menegotto VM; Gevaerd S; Buss Zda S; Frode TS

2012-01-01

58

Mate choice for a male carotenoid-based ornament is linked to female dietary carotenoid intake and accumulation  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background The coevolution of male traits and female mate preferences has led to the elaboration and diversification of sexually selected traits; however the mechanisms that mediate trait-preference coevolution are largely unknown. Carotenoid acquisition and accumulation are key determinants of the expression of male sexually selected carotenoid-based coloration and a primary mechanism maintaining the honest information content of these signals. Carotenoids also influence female health and reproduction in ways that may alter the costs and benefits of mate choice behaviours and thus provide a potential biochemical link between the expression of male traits and female preferences. To test this hypothesis, we manipulated the dietary carotenoid levels of captive female house finches (Carpodacus mexicanus) and assessed their mate choice behavior in response to color-manipulated male finches. Results Females preferred to associate with red males, but carotenoid supplementation did not influence the direction or strength of this preference. Females receiving a low-carotenoid diet were less responsive to males in general, and discrimination among the colorful males was positively linked to female plasma carotenoid levels at the beginning of the study when the diet of all birds was carotenoid-limited. Conclusions Although female preference for red males was not influenced by carotenoid intake, changes in mating responsiveness and discrimination linked to female carotenoid status may alter how this preference is translated into choice. The reddest males, with the most carotenoid rich plumage, tend to pair early in the breeding season. If carotenoid-related variations in female choice behaviour shift the timing of pairing, then they have the potential to promote assortative mating by carotenoid status and drive the evolution of carotenoid-based male plumage coloration.

Toomey Matthew B; McGraw Kevin J

2012-01-01

59

Assortative mating for obesity.  

UK PubMed Central (United Kingdom)

BACKGROUND: Assortative mating is the nonrandom mating of individuals with respect to phenotype and cultural factors. Previous studies of assortative mating for obesity have indicated that it may have contributed to the obesity epidemic. However, those studies all used body mass index or skinfold thicknesses to measure obesity and did not always account for potential confounding factors. OBJECTIVE: We aimed to assess the level of assortative mating for obesity by using dual-energy X-ray absorptiometry to characterize body composition. DESIGN: This was a cross-sectional study of 42 couples. RESULTS: Raw spousal correlations showed assortative mating for age, weight, body mass index, lean mass, and fat mass. Removing the effect of age on fat mass strengthened the spousal correlation (r = 0.405). Social homogamy did not appear to be important, because in this sample there was no significant effect of area of origin on age-corrected fat and lean tissue masses for either sex. Regional body-composition analysis showed that subjects with disproportionately large arms (both fat and lean) assortatively mated with partners with the same trait. However, both men and women with high lean tissue in their arms assortatively mated with partners that had a disproportionately low fat content in their legs. CONCLUSIONS: These data confirm that assortative mating for obesity exists when dual-energy X-ray absorptiometry is used to evaluate adiposity. We hypothesize that assortative mating may have contributed to the obesity epidemic because the time course of obesity development has shifted progressively earlier, allowing singles in their late teens and early twenties to more easily distinguish partners with obese and lean phenotypes.

Speakman JR; Djafarian K; Stewart J; Jackson DM

2007-08-01

60

Altered bone status in unilateral testicular cancer survivors: Role of CYP2R1 and its luteinizing hormone-dependency.  

UK PubMed Central (United Kingdom)

BACKGROUND: Recent data suggest a potential role of testis in vitamin D activation, where Leydig cells could represent key players in this process since they express the highest amount of CYP2R1, a key enzyme involved in vitamin D 25 hydroxylation. AIM: To evaluate bone status in unilateral orchiectomy and to assess in vivo and in vitro LH-dependency of Vitamin D 25 hydroxylation. SUBJECTS AND METHODS: 125 normotestosteronemic patients with testicular cancer (TC), featured by unilateral orchiectomy and 41 age-matched healthy male controls were studied in the Center for Human Reproduction Pathology at the University of Padova. To evaluate LH-dependency of Vitamin D 25 hydroxylation in vitro, Leydig cell cultures were stimulated with hCG and assessed for CYP2R1 expression, whereas in vivo 10 hypogonadotropic hypogonadal (HH) patients were evaluated before and after treatment with gonadotropins for bone metabolism markers. Hormonal pattern and bone metabolism markers were measured in all subjects, whereas 105 patients and 41 controls underwent bone densitometry by DEXA. RESULTS: In TC patients 25-hydroxyvitamin D levels were significantly lower compared to controls. Furthermore, 23.8% of patients with TC displayed low bone density (Z-score <-2 SD). None of the 41 control subjects showed any significant alteration of BMD. In vitro and in vivo studies revealed that CYP2R1 expression in Leydig cells appeared to be hCG dependent. CONCLUSION: Our data show an association between TC and alteration of the bone status, despite unvaried androgen and estrogen levels, suggesting the evaluation of bone status and possible vitamin D deficiency in TC survivors.

Foresta C; Selice R; De Toni L; Di Mambro A; Carraro U; Plebani M; Garolla A

2013-06-01

 
 
 
 
61

Matings with laminations  

CERN Document Server

We give a topological description of the space of quadratic rational maps with superattractive two-cycles: its "non-escape locus" M2 (the analog of the Mandelbrot set M) is locally connected, it is the continuous image of M under a canonical map, and it can be described as M (minus the 1/2-limb), mated with the lamination of the basilica. The latter statement is a refined version of a conjecture of Ben Wittner, which in its original version requires local connectivity of M to even be stated. Our methods of mating with a lamination also apply to dynamical matings of certain non-locally connected Julia sets.

Dudko, Dzmitry

2011-01-01

62

Zinc supplementation does not alter sensitive biomarkers of copper status in healthy boys.  

UK PubMed Central (United Kingdom)

The tolerable upper intake levels (UL) for zinc for children were based on limited data and there is concern that the UL may be set too low. The first effect of excessive zinc intake is a reduction in copper status. The primary objective of this study was to examine the effect of zinc supplementation on copper status in children. Healthy, 6- to 8-y-old boys from Ontario, Canada were assigned to take a placebo (n = 10) or 5 mg (n = 10), 10 mg (n = 9), or 15 mg (n = 8) of zinc supplement daily for 4 mo in a double-blinded, placebo-controlled, randomized trial. Biochemical measures were evaluated at baseline and after 2 and 4 mo of supplementation. Food records were completed near the baseline and 4-mo visits. Age and anthropometric measurements did not differ (P > 0.05) between treatment groups at baseline. Mean zinc intakes from food alone (10.9-14.8 mg zinc/d) approached or exceeded the UL of 12 mg/d. Compared with the placebo group, the zinc groups had a greater change in the urine zinc:creatinine ratio at 4 mo (P = 0.02). Traditional (plasma copper and ceruloplasmin activity) and more sensitive biomarkers of copper status, including erythrocyte SOD1 activity and the erythrocyte CCS:SOD1 protein ratio, were unchanged in zinc-supplemented boys, demonstrating that copper status was not depressed. Serum lipid measures and hemoglobin concentrations were also unaffected and gastrointestinal symptoms were not reported. These data provide evidence in support of the need for reexamining the current UL for zinc for children.

Bertinato J; Simpson JR; Sherrard L; Taylor J; Plouffe LJ; Van Dyke D; Geleynse M; Dam YY; Murphy P; Knee C; Vresk L; Holland N; Quach H; Mack DR; Cooper M; L'abbé MR; Hayward S

2013-03-01

63

Altered health status and quality of life in South Asians with coronary artery disease.  

UK PubMed Central (United Kingdom)

BACKGROUND: People of South Asian (SA) ancestry are susceptible to coronary artery disease (CAD). Although studies suggest that SA with CAD has a worse prognosis compared with Europeans, it is unknown whether corresponding differences in functional status and quality-of-life (QOL) measures exist. Accordingly, we compared symptoms, function, and QOL in SA and European Canadians with CAD using the Seattle Angina Questionnaire (SAQ). METHODS: Using the Alberta Provincial Project for Outcomes Assessment in Coronary Heart Disease, an outcomes registry that captures patients undergoing cardiac catheterization in Alberta, Canada, we identified 635 SA and 18,934 European patients with angiographic CAD from January 1995 to December 2006 who reported health status outcomes using the SAQ at 1 year after the index catheterization. To obtain comparable clinical variables among SA and Europeans, we used a propensity score-matching technique. RESULTS: One-year adjusted mean (SD) scores were significantly lower in SA compared with European Canadians for most SAQ domains: exertional capacity (75 [23] vs 80 [23], P = .011), anginal stability (77 [28] vs 77 [27], P = .627), anginal frequency (86 [23] vs 88 [20], P < .001), treatment satisfaction (86 [19] vs 89 [16], P < .001), and SAQ QOL (71 [24] vs 76 [21], P < .001). These results could not be accounted for by differences in baseline QOL scores or changes in health status from baseline to 1 year. CONCLUSION: South Asian Canadians with established CAD have significantly worse health status outcomes at 1 year after angiography compared with European Canadians. Further studies are warranted to improve functional outcomes in SA with CAD.

Bainey KR; Norris CM; Gupta M; Southern D; Galbraith D; Knudtson ML; Graham MM

2011-09-01

64

Regulation of hypoxia inducible factor-1? expression by the alteration of redox status in HepG2 cells  

Science.gov (United States)

Hypoxia inducible factor-1 (HIF-1) has been considered as a critical transcriptional factor in response to hypoxia. It can increase P-glycoprotein (P-Gp) thus generating the resistant effect to chemotherapy. At present, the mechanism regulating HIF-1? is still not fully clear in hypoxic tumor cells. Intracellular redox status is closely correlated with hypoxic micro-environment, so we investigate whether alterations in the cellular redox status lead to the changes of HIF-1? expression. HepG2 cells were exposed to Buthionine sulphoximine (BSO) for 12 h prior to hypoxia treatment. The level of HIF-1? expression was measured by Western blot and immunocytochemistry assays. Reduce glutathione (GSH) concentrations in hypoxic cells were determined using glutathione reductase/5,5'-dithiobis-(2-nitrob-enzoic acid) (DTNB) recycling assay. To further confirm the effect of intracellular redox status on HIF-1? expression, N-acetylcysteine (NAC) was added to culture cells for 8 h before the hypoxia treatment. The levels of multidrug resistance gene-1 (MDR-1) and erythropoietin (EPO) mRNA targeted by HIF-1? in hypoxic cells were further determined with RT-PCR, and then the expression of P-Gp protein was observed by Western blotting. The results showed that BSO pretreatment down-regulated HIF-1? and the effect was concentration-dependent, on the other hand, the increases of intracellular GSH contents by NAC could partly elevate the levels of HIF-1? expression. The levels of P-Gp (MDR-1) and EPO were concomitant with the trend of HIF-1? expression. Therefore, our data indicate that the changes of redox status in hypoxic cells may regulate HIF-1? expression and provide valuable information on tumor chemotherapy.

2011-01-01

65

Regulation of hypoxia inducible factor-1? expression by the alteration of redox status in HepG2 cells  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Hypoxia inducible factor-1 (HIF-1) has been considered as a critical transcriptional factor in response to hypoxia. It can increase P-glycoprotein (P-Gp) thus generating the resistant effect to chemotherapy. At present, the mechanism regulating HIF-1? is still not fully clear in hypoxic tumor cells. Intracellular redox status is closely correlated with hypoxic micro-environment, so we investigate whether alterations in the cellular redox status lead to the changes of HIF-1? expression. HepG2 cells were exposed to Buthionine sulphoximine (BSO) for 12 h prior to hypoxia treatment. The level of HIF-1? expression was measured by Western blot and immunocytochemistry assays. Reduce glutathione (GSH) concentrations in hypoxic cells were determined using glutathione reductase/5,5'-dithiobis-(2-nitrob-enzoic acid) (DTNB) recycling assay. To further confirm the effect of intracellular redox status on HIF-1? expression, N-acetylcysteine (NAC) was added to culture cells for 8 h before the hypoxia treatment. The levels of multidrug resistance gene-1 (MDR-1) and erythropoietin (EPO) mRNA targeted by HIF-1? in hypoxic cells were further determined with RT-PCR, and then the expression of P-Gp protein was observed by Western blotting. The results showed that BSO pretreatment down-regulated HIF-1? and the effect was concentration-dependent, on the other hand, the increases of intracellular GSH contents by NAC could partly elevate the levels of HIF-1? expression. The levels of P-Gp (MDR-1) and EPO were concomitant with the trend of HIF-1? expression. Therefore, our data indicate that the changes of redox status in hypoxic cells may regulate HIF-1? expression and provide valuable information on tumor chemotherapy.

Jin Wen-sen; Kong Zhao-lu; Shen Zhi-fen; Jin Yi-zun; Zhang Wu-kui; Chen Guang-fu

2011-01-01

66

Mating a success  

Energy Technology Data Exchange (ETDEWEB)

One of the most critical operations in the entire Hibernia project was the mating of the gravity base structure with the Hibernia Topsides structure. This article described how, on February 28, 1997 these two structures, which were built as two distinct and separate entities, were successfully joined. The topsides structure was floated out to, and over the four support shafts of the gravity base structure. It was mated to within one millimetre of the target contact point. The most advanced technology and equipment was used in the construction and in the mating of the two structures. The completed Hibernia platform now stands 224 metres high and weighs almost 600,000 tonnes. The last milestone remaining is the tow-out of the mated structure to the Hibernia field, scheduled for June 1997. 9 figs.

Anon.

1997-03-01

67

Iron and exercise induced alterations in antioxidant status. Protection by dietary milk proteins.  

Science.gov (United States)

Lipid peroxidation stress induced by iron supplementation can contribute to the induction of gut lesions. Intensive sports lead to ischemia reperfusion, which increases free radical production. Athletes frequently use heavy iron supplementation, whose effects are unknown. On the other hand, milk proteins have in vitro antioxidant properties, which could counteract these potential side effects. The main aims of the study were: (1) to demonstrate the effects of combined exercise training (ET) and iron overload on antioxidant status; (2) to assess the protective properties of casein in vivo; (3) to study the mechanisms involved in an in vitro model. Antioxidant status was assessed by measuring the activity of antioxidant enzymes (superoxide dismutase (SOD); glutathione peroxidase (GSH-Px)), and on the onset of aberrant crypts (AC) in colon, which can be induced by lipid peroxidation. At day 30, all ET animals showed an increase in the activity of antioxidant enzymes, in iron concentration in colon mucosa and liver and in the number of AC compared to untrained rats. It was found that Casein's milk protein supplementation significantly reduced these parameters. Additional information on protective effect of casein was provided by measuring the extent of TBARS formation during iron/ascorbate-induced oxidation of liposomes. Free casein and casein bound to iron were found to significantly reduce iron-induced lipid peroxidation. The results of the overall study suggest that Iron supplementation during intensive sport training would decrease anti-oxidant status. Dietary milk protein supplementation could at least partly prevent occurrence of deleterious effects to tissue induced by iron overload. PMID:17390518

Zunquin, Gautier; Rouleau, Vincent; Bouhallab, Said; Bureau, Francois; Theunynck, Denis; Rousselot, Pierre; Arhan, Pierre; Bougle, Dominique

2006-05-01

68

Iron and exercise induced alterations in antioxidant status. Protection by dietary milk proteins.  

UK PubMed Central (United Kingdom)

Lipid peroxidation stress induced by iron supplementation can contribute to the induction of gut lesions. Intensive sports lead to ischemia reperfusion, which increases free radical production. Athletes frequently use heavy iron supplementation, whose effects are unknown. On the other hand, milk proteins have in vitro antioxidant properties, which could counteract these potential side effects. The main aims of the study were: (1) to demonstrate the effects of combined exercise training (ET) and iron overload on antioxidant status; (2) to assess the protective properties of casein in vivo; (3) to study the mechanisms involved in an in vitro model. Antioxidant status was assessed by measuring the activity of antioxidant enzymes (superoxide dismutase (SOD); glutathione peroxidase (GSH-Px)), and on the onset of aberrant crypts (AC) in colon, which can be induced by lipid peroxidation. At day 30, all ET animals showed an increase in the activity of antioxidant enzymes, in iron concentration in colon mucosa and liver and in the number of AC compared to untrained rats. It was found that Casein's milk protein supplementation significantly reduced these parameters. Additional information on protective effect of casein was provided by measuring the extent of TBARS formation during iron/ascorbate-induced oxidation of liposomes. Free casein and casein bound to iron were found to significantly reduce iron-induced lipid peroxidation. The results of the overall study suggest that Iron supplementation during intensive sport training would decrease anti-oxidant status. Dietary milk protein supplementation could at least partly prevent occurrence of deleterious effects to tissue induced by iron overload.

Zunquin G; Rouleau V; Bouhallab S; Bureau F; Theunynck D; Rousselot P; Arhan P; Bougle D

2006-05-01

69

Ethanol Intake during Lactation Alters Milk Nutrient Composition and Growth and Mineral Status of Rat Pups  

Directory of Open Access Journals (Sweden)

Full Text Available Lactating Wistar rats were fed a liquid diet containing either ethanol [ethanol-fed group (EFG)] or an isocaloric amount of carbohydrate [pair-fed group (PFG)] from day 1 postpartum up to day 14 of lactation, to investigate micro/macronutrient milk composition and the mineral status of pups. EFG presented a reduction of daily milk production and milk composition was significantly higher in protein and lower in carbohydrate, while the lipid content was similar to that of PFG. When compared to PFG, the milk of EFG had a decreased proportion of C22:6 n-3 fatty acid and an increase in medium-chain fatty acids and of several minerals. Pups of EFG showed reduced growth and a lower concentration of Cu and Sr in plasma and lower concentrations of Ca, P and Cl, and higher concentrations of Cd in the brain. We conclude that maternal EtOH intake greatly impairs lactational performance and modifies the mineral status of pups.

CÍNTIA R.P AZARA; INGRID C MAIA; CAROLINA N RANGEL; MÁRIO A.C SILVA-NETO; RENATA F.B SERPA; EDGAR F.O DE JESUS; MARIA G TAVARES  DO CARMO; ELIANE FIALHO

2008-01-01

70

Alteration of Enzyme Aspartate Transaminase in Goat Milk related to Udder health status  

Directory of Open Access Journals (Sweden)

Full Text Available The present experiment was conducted to study variations in milk SCC and pH, along with activity of whey enzyme Aspartate transaminase (AST) in relation to different udder health status of goats. The average values of milk SCC, pH, and AST differed significantly (P<0.01) among various udder health status of goat. The mean difference for SCC of milk showed significant (P<0.01) differences for all the comparisons varying from 6.88 to 41.88 x 105 cells/ml. The average milk pH values ranged from 6.40 ± 0.09 to 7.36 ± 0.01. The milk SCC and pH increased by 1.039 x 105 cells/ml and 0.24 respectively for each unit rise in CMT score. Similarly, the activity of AST increased by 14.04 AST U/ml for each unit rise in CMT scores. [Vet. World 2009; 2(1.000): 24-26

Khodke; M.V.; Bonde,S.W. and Ambade; R.B.

2009-01-01

71

Leptin modulates lymphocytes' adherence to hepatic stellate cells is associated with oxidative status alterations.  

UK PubMed Central (United Kingdom)

We investigated leptin effects on lymphocyte interactions with hepatic-stellate-cells (HSCs). Leptin showed pro-fibrotic effects on HSCs with oxidative status imbalance. In co-cultures, leptin activates HSCs and consequently adhered HCV-lymphocytes more than healthy ones. Leptin also increased healthy and HCV lymphocyte proliferations; increased their reactive-oxygen-species; decreased antioxidants (reduced-glutathione) levels while inhibited apoptosis only of HCV-lymphocytes. The leptin-treated HCV-lymphocytes activated HSCs, increase interleukin-4 while decreased their apoptosis. Leptin-receptor-deficient (db-db)-HSCs did not adhere lymphocytes. db/db-lymphocytes however showed fewer adherences to HSCs when compared to WT-counterparts. This study presents immune and oxidative modulatory effects of leptin on lymphocytes and their consequent interaction with HSCs.

Abu-Tair L; Doron S; Mahamid M; Amer J; Safadi R

2013-09-01

72

Altered DNA repair, oxidative stress and antioxidant status in coronary artery disease.  

UK PubMed Central (United Kingdom)

Coronary artery disease (CAD) is a multifactorial disease caused by the interplay of environmental risk factors with multiple predisposing genes. The present study was undertaken to evaluate the role of DNA repair efficiency and oxidative stress and antioxidant status in CAD patients. Malonaldehyde (MDA), which is an indicator of oxidative stress, and mean break per cell (b/c) values, which is an indicator of decreased DNA repair efficiency, were found to be significantly increased in patients compared to normal controls (P less than 0.05) whereas ascorbic acid and GSH were found to be lower among patients than the control group. It has been found that elevated oxidative stress decreased antioxidant level and decreased DNA repair efficiency can contribute to the development of CAD. This study also showed that high MDA, low ascorbic acid and GSH were significantly associated with high b/c value.

Simon AS; Chithra V; Vijayan A; Dinesh RD; Vijayakumar T

2013-06-01

73

Mitochondrial oxidative injury and energy metabolism alteration in rat fatty liver: effect of the nutritional status.  

Science.gov (United States)

Hepatic steatosis is associated with mitochondrial oxidative alterations. This study aimed to characterize in a choline-deficient model of rat fatty liver whether this oxidative imbalance is related to an impairment of the capacity of ATP synthesis both under fed conditions and after starvation, which may sensitize mitochondria to oxidative injury. Mitochondria were isolated from normal and fatty livers of fed or 18-hour fasted rats. Oxidative injury was evaluated by measuring the mitochondrial content of thiobarbituric reactive substances, protein carbonyls, glutathione, and protein sulfhydryls. The mitochondrial F(0)F(1)-ATP synthase content, tissue ATP concentration, and liver histology were also determined. Compared with normal liver, under fed conditions, fatty livers showed a greater mitochondrial content of oxidized lipids and proteins together with a low concentration of sulfhydryls and glutathione. The mitochondrial catalytic beta-F(1) subunit of the F(0)F(1)-ATP synthase was about 35% lower in fatty livers. Hepatic ATP was also significantly reduced in fatty liver. Starvation exacerbated mitochondrial oxidative injury in both groups but to a greater extent in fatty livers. In the steatotic group, fasting induced a significant decrease of the ATP levels, which was accompanied by a 70% fall of the catalytic beta-F(1) subunit. These data indicate that the mitochondrial oxidative alterations in fatty livers are associated with an important reduction of the F(0)F(1)-ATP synthase. These changes, which are greatly exacerbated after starvation, may account for the reduced synthesis of the hepatic ATP observed in the presence of fatty infiltration. PMID:11283843

Vendemiale, G; Grattagliano, I; Caraceni, P; Caraccio, G; Domenicali, M; Dall'Agata, M; Trevisani, F; Guerrieri, F; Bernardi, M; Altomare, E

2001-04-01

74

Altered energy status of primary cerebellar granule neuronal cultures from rats exposed to lead in the pre- and neonatal period.  

UK PubMed Central (United Kingdom)

This paper examines the effect of pre- and neonatal exposure of rats to lead (0.1% lead acetate in drinking water, resulting in rat offspring whole blood lead concentration (Pb-B) 4?g/dL) on the energy status of neuronal mitochondria by measuring changes in ATP, ADP, AMP, adenosine, TAN concentration, adenylate energy charge value (AEC) and mitochondrial membrane potential in primary cerebellar granule neurons (CGC) in dissociated cultures. Fluorescence studies were performed to imaging and evaluate mitochondria mass, mitochondrial membrane potential, intracellular and mitochondrial reactive oxygen species (ROS) production. The Na(+)/K(+) ATPase activity in intact CGC was measured spectrophotometrically. Our data shows that pre- and neonatal exposure of rats to Pb, even below the threshold of whole blood Pb value considered safe for people, affects the energy status of cultured primary cerebellar granule neurons through a decrease in ATP and TAN concentrations and AEC value, inhibition of Na(+)/K(+) ATPase, and increase in intracellular and mitochondrial ROS concentration. These observations suggest that even these low levels of Pb are likely to induce important alterations in neuronal function that could play a role in neurodegeneration.

Baranowska-Bosiacka I; Gutowska I; Marchetti C; Rutkowska M; Marchlewicz M; Kolasa A; Prokopowicz A; Wiernicki I; Piotrowska K; Ba?kiewicz M; Safranow K; Wiszniewska B; Chlubek D

2011-02-01

75

Altered Antioxidant-Oxidant Status in the Aqueous Humor and Peripheral Blood of Patients with Retinitis Pigmentosa  

Science.gov (United States)

Retinitis Pigmentosa is a common form of hereditary retinal degeneration constituting the largest Mendelian genetic cause of blindness in the developed world. It has been widely suggested that oxidative stress possibly contributes to its pathogenesis. We measured the levels of total antioxidant capacity, free nitrotyrosine, thiobarbituric acid reactive substances (TBARS) formation, extracellular superoxide dismutase (SOD3) activity, protein, metabolites of the nitric oxide/cyclic GMP pathway, heme oxygenase-I and inducible nitric oxide synthase expression in aqueous humor or/and peripheral blood from fifty-six patients with retinitis pigmentosa and sixty subjects without systemic or ocular oxidative stress-related disease. Multivariate analysis of covariance revealed that retinitis pigmentosa alters ocular antioxidant defence machinery and the redox status in blood. Patients with retinitis pigmentosa present low total antioxidant capacity including reduced SOD3 activity and protein concentration in aqueous humor. Patients also show reduced SOD3 activity, increased TBARS formation and upregulation of the nitric oxide/cyclic GMP pathway in peripheral blood. Together these findings confirmed the hypothesis that patients with retinitis pigmentosa present reduced ocular antioxidant status. Moreover, these patients show changes in some oxidative-nitrosative markers in the peripheral blood. Further studies are needed to clarify the relationship between these peripheral markers and retinitis pigmentosa.

Martinez-Fernandez de la Camara, Cristina; Salom, David; Sequedo, Ma Dolores; Hervas, David; Marin-Lambies, Cristina; Aller, Elena; Jaijo, Teresa; Diaz-LLopis, Manuel; Millan, Jose Maria; Rodrigo, Regina

2013-01-01

76

The necessities and luxuries of mate preferences: testing the tradeoffs.  

UK PubMed Central (United Kingdom)

Social exchange and evolutionary models of mate selection incorporate economic assumptions but have not considered a key distinction between necessities and luxuries. This distinction can clarify an apparent paradox: Status and attractiveness, though emphasized by many researchers, are not typically rated highly by research participants. Three studies supported the hypothesis that women and men first ensure sufficient levels of necessities in potential mates before considering many other characteristics rated as more important in prior surveys. In Studies 1 and 2, participants designed ideal long-term mates, purchasing various characteristics with 3 different budgets. Study 3 used a mate-screening paradigm and showed that people inquire 1st about hypothesized necessities. Physical attractiveness was a necessity to men, status and resources were necessities to women, and kindness and intelligence were necessities to both.

Li NP; Bailey JM; Kenrick DT; Linsenmeier JA

2002-06-01

77

Short-Term Feed Deprivation Alters Immune Status of Surface Mucosa in Channel Catfish (Ictalurus punctatus).  

Science.gov (United States)

Short-term feed deprivation (or fasting) is a common occurrence in aquacultured fish species whether due to season, production strategies, or disease. In channel catfish (Ictalurus punctatus) fasting impacts susceptibility to several bacterial pathogens including Flavobacterium columnare, the causative agent of columnaris disease. As columnaris gains entry through the gills and skin of fish, we examined here changes in transcriptional regulation induced in these surface mucosal tissues due to short-term (7 day) fasting. RNA-seq expression analysis revealed a total of 1,545 genes perturbed by fasting. Fasting significantly altered expression of critical innate immune factors in a manner consistent with lower immune fitness as well as dysregulating key genes involved in energy metabolism and cell cycling/proliferation. Downregulation of innate immune actors such as iNOS2b, Lysozyme C, and peptidoglycan recognition protein 6 is predicted to impact the delicate recognition/tolerance balance for commensal and pathogenic bacteria on the skin and gill. The highlighted expression profiles reveal potential mechanistic similarities between gut and surface mucosa and underscore the complex interrelationships between nutrition, mucosal integrity, and immunity in teleost fish. PMID:24023952

Liu, Lisa; Li, Chao; Su, Baofeng; Beck, Benjamin H; Peatman, Eric

2013-09-04

78

Short-Term Feed Deprivation Alters Immune Status of Surface Mucosa in Channel Catfish (Ictalurus punctatus).  

UK PubMed Central (United Kingdom)

Short-term feed deprivation (or fasting) is a common occurrence in aquacultured fish species whether due to season, production strategies, or disease. In channel catfish (Ictalurus punctatus) fasting impacts susceptibility to several bacterial pathogens including Flavobacterium columnare, the causative agent of columnaris disease. As columnaris gains entry through the gills and skin of fish, we examined here changes in transcriptional regulation induced in these surface mucosal tissues due to short-term (7 day) fasting. RNA-seq expression analysis revealed a total of 1,545 genes perturbed by fasting. Fasting significantly altered expression of critical innate immune factors in a manner consistent with lower immune fitness as well as dysregulating key genes involved in energy metabolism and cell cycling/proliferation. Downregulation of innate immune actors such as iNOS2b, Lysozyme C, and peptidoglycan recognition protein 6 is predicted to impact the delicate recognition/tolerance balance for commensal and pathogenic bacteria on the skin and gill. The highlighted expression profiles reveal potential mechanistic similarities between gut and surface mucosa and underscore the complex interrelationships between nutrition, mucosal integrity, and immunity in teleost fish.

Liu L; Li C; Su B; Beck BH; Peatman E

2013-01-01

79

Olfactory perception in women with physiologically altered hormonal status (during pregnancy and postmenopause)  

Directory of Open Access Journals (Sweden)

Full Text Available Introduction Olfaction is considered to be the ability to: perceive, conduct and recognize scents and odors. With its numerous connections to the limbic system and reticular formation, the olfactory system affects regulation of numerous vegetative functions, visceral functions and sexual behavior. Since estrogen and progesterone protect the olfactory function, changes in their levels in particular physiological states in women (in pregnancy and postmenopause) exert an influence on the ability to feel and recognize smells. It has its role in creating emotions and adjustment of visceral and vegetative response to particular emotional states. Also, it represents the connection between higher cortical functions and the endocrine system. Material and methods Our investigation was performed at the Ear, Nose and Throat Clinic in Novi Sad. The research included 80 healthy women classified into 4 groups; 20 women aged between 20 and 30; 20 women in the first trimester of pregnancy aged between 20 and 30; 20 premenopausal women aged between 41 and 50; and 20 women at least 3 years in postmenopause, aged between 41 and 50. For our research we used an olfactometer and the Fortunato-Niccolini method. Results and discussion In pregnancy the thresholds of perception (TP) and identification (TI) of examined substances were slightly lower in comparison to nonpregnant women of the same ages, but without any statistical significance (p>0.05). In climacteric-postmenopausal women there was a significant decrease of olfactory ability in comparison to nonmenopausal women of the same ages (p<0.01). Conclusion All changes of the olfactory function in pregnancy are explained by mental changes of pregnant women as well as their hormonal status. Significant decrease of olfactory ability in postmenopause is explained by decline in sexual hormone levels.

Savovi? Slobodan N.; Nin?i? Dejan P.; Lemaji? Slobodanka N.; Pilija Vladimir I.; Mandi? Aljoša; Rajovi? Jelka; Iveti?-Petrovi? Vesna R.

2002-01-01

80

Prevalence of non-convulsive seizure and other electroencephalographic abnormalities in ED patients with altered mental status.  

UK PubMed Central (United Kingdom)

Four to ten percent of patients evaluated in emergency departments (ED) present with altered mental status (AMS). The prevalence of non-convulsive seizure (NCS) and other electroencephalographic (EEG) abnormalities in this population is unknown. OBJECTIVES: To identify the prevalence of NCS and other EEG abnormalities in ED patients with AMS. METHODS: A prospective observational study at 2 urban ED. Inclusion: patients ?13 years old with AMS. Exclusion: An easily correctable cause of AMS (e.g. hypoglycemia). A 30-minute standard 21-electrode EEG was performed on each subject upon presentation. Outcome: prevalence of EEG abnormalities interpreted by a board-certified epileptologist. EEGs were later reviewed by 2 blinded epileptologists. Inter-rater agreement (IRA) of the blinded EEG interpretations is summarized with ?. A multiple logistic regression model was constructed to identify variables that could predict the outcome. RESULTS: Two hundred fifty-nine patients were enrolled (median age: 60, 54% female). Overall, 202/259 of EEGs were interpreted as abnormal (78%, 95% confidence interval [CI], 73-83%). The most common abnormality was background slowing (58%, 95% CI, 52-68%) indicating underlying encephalopathy. NCS (including non-convulsive status epilepticus [NCSE]) was detected in 5% (95% CI, 3-8%) of patients. The regression analysis predicting EEG abnormality showed a highly significant effect of age (P < .001, adjusted odds ratio 1.66 [95% CI, 1.36-2.02] per 10-year age increment). IRA for EEG interpretations was modest (?: 0.45, 95% CI, 0.36-0.54). CONCLUSIONS: The prevalence of EEG abnormalities in ED patients with undifferentiated AMS is significant. ED physicians should consider EEG in the evaluation of patients with AMS and a high suspicion of NCS/NCSE.

Zehtabchi S; Abdel Baki SG; Omurtag A; Sinert R; Chari G; Malhotra S; Weedon J; Fenton AA; Grant AC

2013-09-01

 
 
 
 
81

Mating pheromones of heterobasidiomycetous yeasts  

Science.gov (United States)

Two mating pheromones, which induce mating tube formation, were isolated from Rhodosporidium toruloides (rhodotorucine A) and Tremella mesenterica (tremerogen A-10). These mating pheromones are lipophilic oligopeptides having S-alkylated cysteine at the C-terminus but different amino acid sequences. Synthetic analogues of these pheromones revealed the structure-activity relationships. Metabolism of rhodotorucine A was also studied by using labeled pheromones.

Kamiya, Y.; Sakurai, A.

1981-03-01

82

Do Couples Assortatively Mate?  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This study investigated the role of intelligence, conservatism, personal values, and Openness in assortative mating. A sample of 32 couples was given questionnaires, which measured self-rated intelligence and partner-rated Openness, conservatism and values. Intraclass correlations (ICCs) were used...

Mistry, Navin

83

Female fitness optimum at intermediate mating rates under traumatic mating.  

UK PubMed Central (United Kingdom)

Traumatic mating behaviors often bear signatures of sexual conflict and are then typically considered a male strategy to circumvent female choice mechanisms. In an extravagant mating ritual, the hermaphroditic sea slug Siphopteron quadrispinosum pierces the integument of their mating partners with a syringe-like penile stylet that injects prostate fluids. Traumatic injection is followed by the insertion of a spiny penis into the partner's gonopore to transfer sperm. Despite traumatic mating, field mating rates exceed those required for female fertilization insurance, possibly because costs imposed on females are balanced by direct or indirect benefits of multiple sperm receipt. To test this idea, we exposed animals to a relevant range of mating opportunity regimes and assessed the effects on mating behavior and proxies of female fitness. We find penis intromission duration to decrease with mating rates, and a female fecundity maximum at intermediate mating rates. The latter finding indicates that benefits beyond fertilization insurance can make higher mating rates also beneficial from a female perspective in this traumatically mating species.

Lange R; Gerlach T; Beninde J; Werminghausen J; Reichel V; Anthes N

2012-01-01

84

Mycophenolate mofetil alters the antioxidant status in duodenum of rats: Implication for silymarin usage in mycophenolate mofetil induced gastrointestinal disorders  

Directory of Open Access Journals (Sweden)

Full Text Available Mycophenolate mofetil (MMF) as an immunosuppressive agent is used to prevent graftrejection. One of the adverse effects of long time administration of MMF is the gastrointestinaldisorder. This study aimed to investigate the gastroprotective effect of silymarin (SMN) onMMF-induced gastrointestinal (GI) disorders. Twenty-four adult female Wistar rats wereassigned into three groups including the control and test groups. The control animals receivedsaline(5 mL kg-1)andthe test animals were treated with MMF (40 mg kg-1, orally) and saline,MMF and silymarin (SMN, 50 mg kg-1, orally) for 14 consecutive days, respectively. To evaluatethe GI disorders due to the MMF-induced oxidative stress and subsequently the protective effectof SMN, malondialdehyde (MDA),total thiol molecules(TTM) levels and total anti-oxidantcapacity (TAC) were determined. Additionally, histopathological examinations in the duodenalregion of small intestine were performed. The MMF-increased level of MDA was reduced bySMN administration, while the MMF-reduced level of TTM increased significantly (p< 0.05) bySMN administration. Histopathological examinations showed the goblet cell reduction andcongestion in the MMF-received animals; while SMN was able to improve the MMF-inducedgoblet cell reduction and congestion. Our data suggest that the MMF-induced GI disorders arecharacterized by changes in antioxidant status, which presented by the elevation of MDA leveland reduction of TTM concentration. Moreover, the improved biochemical alterations andhistopathologic damages by SMN indicating its gastroprotective and antioxidant effects

Sanaz Sheikhzadeh; Hassan Malekinejad; Rahim Hobbenaghi

2013-01-01

85

Inhibition of glutathione biosynthesis alters compartmental redox status and the thiol proteome in organogenesis-stage rat conceptuses.  

UK PubMed Central (United Kingdom)

Developmental signals that control growth and differentiation are regulated by environmental factors that generate reactive oxygen species (ROS) and alter steady-state redox environments in tissues and fluids. Protein thiols are selectively oxidized and reduced in distinct spatial and temporal patterns in conjunction with changes in glutathione/glutathione disulfide (GSH/GSSG) and cysteine/cystine (Cys/CySS) redox potentials (Eh) to regulate developmental signaling. The purpose of this study was to measure compartment-specific thiol redox status in cultured organogenesis-stage rat conceptuses and to evaluate the impact of thiol oxidation on the redox proteome. The visceral yolk sac (VYS) has the highest initial (0h) total intracellular GSH (GSH+2GSSG) concentration (5.5mM) and the lowest Eh (-223mV) as determined by HPLC analysis. Total embryo (EMB) GSH concentrations ranged lower (3.2mM) and were only slightly more oxidized than the VYS. Total GSH concentrations in yolk sac fluid (YSF) and amniotic fluid (AF) are >500-fold lower than in tissues and are highly oxidized (YSF Eh=-121mV and AF Eh=-49mV). Steady-state total Cys concentrations (Cys+2CySS) were significantly lower than GSH in tissues but were otherwise equal in VYS and EMB near 0.5mM. On gestational day 11, total GSH and Cys concentrations in EMB and VYS increase significantly over the 6h time course while Eh remains relatively constant. The Eh (GSH/GSSG) in YSF and AF become more reduced over time while Eh (Cys/CySS) become more oxidized. Addition of L-buthionine-S,R-sulfoximine (BS0) to selectively inhibit GSH synthesis and mimic the effects of some GSH-depleting environmental chemicals significantly decreased VYS and EMB GSH and Cys concentrations and increased Eh over the 6h exposure period, showing a greater overall oxidation. In the YSF, BSO caused a significant increase in total Cys concentrations to 1.7mM but did not significantly change the Eh for Cys/CySS. A significant net oxidation was seen in the BSO-treated AF compartment after 6h. Biotinylated iodoacetamide (BIAM) labeling of proteins revealed the significant thiol oxidation of many EMB proteins following BSO treatment. Quantitative changes in the thiol proteome, associated with developmentally relevant pathways, were detected using isotope coded affinity tag (ICAT) labeling and mass spectroscopy. Adaptive pathways were selectively enriched with increased concentrations of proteins involved in mRNA processing (splicesome) and mRNA stabilization (glycolysis, GAPDH), as well as protein synthesis (aminoacyl-tRNA) and protein folding (antigen processing, Hsp70, protein disulfide isomerase). These results show the ability of chemical and environmental modulators to selectively alter compartmental intracellular and extracellular GSH and Cys concentrations and change their corresponding Eh within the intact viable conceptus. The altered Eh were also of sufficient magnitude to alter the redox proteome and change relative protein concentrations, suggesting that the mechanistic links through which environmental factors inform and regulate developmental signaling pathways may be discovered using systems developmental biology techniques.

Harris C; Shuster DZ; Roman Gomez R; Sant KE; Reed MS; Pohl J; Hansen JM

2013-10-01

86

Mating behavior of Cephalonomia tarsalis (Ashmead) (Hymenoptera: Bethylidae) and the effect of female mating frequency on offspring production  

UK PubMed Central (United Kingdom)

The courtship behavior of Cephalonomia tarsalis, a solitary semiectoparasitoid of Oryzaephilus surinamensis, was investigated in the laboratory. Courtship behavior includes a series of stereotypic movements. Males play the most active role, executing the majority of courtship action, and females respond with relatively limited observable behaviors. Males typically keep antennae still during encounters with females prior to mounting, which may be correlated with recognition of the female's sexual status. After mounting, males display a series of movements on females, such as antennae touching female's antennae, antennae or mouth touching female's head or thorax, and walking around on female, which may serve to stimulate females towards increased receptivity. Females signal receptivity by assuming a stereotypical posture of remaining stationary, with head down, and antennae still in front of the body. The male then inserts his aedeagus and the pair copulates. After an average of 40.4 s of copulation, females signal the end of copulation by waving the antennae and moving away from the copulation site. Males continue copulating for a short time after females start moving but dismount soon thereafter. After dismounting, the two wasps move away from each other immediately, and they typically begin grooming. Neither males nor females exhibit mating preference based on mate's mating status in both choice and no-choice tests. The male is polygynous and the mated female can mate multiple times within the first 3 days after starting oviposition. However, female mating frequency does not affect the production of female progeny.

Cheng LL; Howard RW; Campbell JF; Charlton RE; Nechols JR; Ramaswamy SB

2004-03-01

87

Illusions promote mating success in great bowerbirds.  

UK PubMed Central (United Kingdom)

Sexual selection studies normally compare signal strengths, but signal components and sensory processing may interact to create misleading or attention-capturing illusions. Visual illusions can be produced by altering object and scene geometry in ways that trick the viewer when seen from a particular direction. Male great bowerbirds actively maintain size-distance gradients of objects on their bower courts that create forced-perspective illusions for females viewing their displays from within the bower avenue. We show a significant relationship between mating success and the female's view of the gradient; this view explains substantially more variance in mating success than the strength of the gradients. Illusions may be widespread in other animals because males of most species display to females with characteristic orientation and distance, providing excellent conditions for illusions.

Kelley LA; Endler JA

2012-01-01

88

Tissue remodeling: a mating-induced differentiation program for the Drosophila oviduct  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background In both vertebrates and invertebrates, the oviduct is an epithelial tube surrounded by visceral muscles that serves as a conduit for gamete transport between the ovary and uterus. While Drosophila is a model system for tubular organ development, few studies have addressed the development of the fly's oviduct. Recent studies in Drosophila have identified mating-responsive genes and proteins whose levels in the oviduct are altered by mating. Since many of these molecules (e.g. Muscle LIM protein 84B, Coracle, Neuroglian) have known roles in the differentiation of muscle and epithelia of other organs, mating may trigger similar differentiation events in the oviduct. This led us to hypothesize that mating mediates the last stages of oviduct differentiation in which organ-specific specializations arise. Results Using electron- and confocal-microscopy we identified tissue-wide post-mating changes in the oviduct including differentiation of cellular junctions, remodeling of extracellular matrix, increased myofibril formation, and increased innervation. Analysis of once- and twice-mated females reveals that some mating-responsive proteins respond only to the first mating, while others respond to both matings. Conclusion We uncovered ultrastructural changes in the mated oviduct that are consistent with the roles that mating-responsive proteins play in muscle and epithelial differentiation elsewhere. This suggests that mating triggers the late differentiation of the oviduct. Furthermore, we suggest that mating-responsive proteins that respond only to the first mating are involved in the final maturation of the oviduct while proteins that remain responsive to later matings are also involved in maintenance and ongoing function of the oviduct. Taken together, our results establish the oviduct as an attractive system to address mechanisms that regulate the late stages of differentiation and maintenance of a tubular organ.

Kapelnikov Anat; Rivlin Patricia K; Hoy Ronald R; Heifetz Yael

2008-01-01

89

Mating behavior of Cnephasia jactatana (Lepidoptera: Tortricidae), an important pest of kiwifruit.  

Science.gov (United States)

Understanding mating behavioral sequence helps us identify the mechanisms of mate assessment and choice, and better evaluate behavior-based pest control strategies. Here we describe the mating behavior of Cnephasia jactatana Walker whose females release a sex pheromone, and determine the effect of male mating status on reproductive success. The mating sequence starts when males approach females and display courtship behavior with antennation and fanning wings. Both males and females may end a mating attempt at any stage of the sequence. Both sexes assess their mates from the initial contact to copulation. Females appear to be choosier at the early and mid-stages than at the late stage of the sequence. Virgin males approach and court females significantly earlier than nonvirgin males. As compared with nonvirgin males, virgin males are approximately 1.6 times more likely to approach and 1.8 times more likely to court females, and four times more likely to achieve mating. This may be attributed to depletion of sperm and accessory gland materials and reduced ability to respond to female sex pheromones in nonvirgin males. The number of attempts by males to acquire mates may be one of the traits that females assess before choosing their mates. PMID:23865204

Jiménez-Pérez, Alfredo; Wang, Qiao; Arzuffi, R

2013-06-01

90

Mating behavior of Cnephasia jactatana (Lepidoptera: Tortricidae), an important pest of kiwifruit.  

UK PubMed Central (United Kingdom)

Understanding mating behavioral sequence helps us identify the mechanisms of mate assessment and choice, and better evaluate behavior-based pest control strategies. Here we describe the mating behavior of Cnephasia jactatana Walker whose females release a sex pheromone, and determine the effect of male mating status on reproductive success. The mating sequence starts when males approach females and display courtship behavior with antennation and fanning wings. Both males and females may end a mating attempt at any stage of the sequence. Both sexes assess their mates from the initial contact to copulation. Females appear to be choosier at the early and mid-stages than at the late stage of the sequence. Virgin males approach and court females significantly earlier than nonvirgin males. As compared with nonvirgin males, virgin males are approximately 1.6 times more likely to approach and 1.8 times more likely to court females, and four times more likely to achieve mating. This may be attributed to depletion of sperm and accessory gland materials and reduced ability to respond to female sex pheromones in nonvirgin males. The number of attempts by males to acquire mates may be one of the traits that females assess before choosing their mates.

Jiménez-Pérez A; Wang Q; Arzuffi R

2013-06-01

91

Thanatosis as an adaptive male mating strategy in the nuptial gift-giving spider Pisaura mirabilis  

DEFF Research Database (Denmark)

Males and females often experience different optima in mating rate, which may cause evolution of female resistance to matings and male counter adaptations to increase mating rate. Males of the spider Pisaura mirabilis display a spectacular mating behavior involving a nuptial gift and thanatosis (death feigning). Thanatosis in a sexual context is exceptional and was suggested to function as an antipredation strategy toward potentially cannibalistic females. If thanatosis serves as a protection strategy, males should death feign in response to female aggression or when they are more vulnerable to attack. We tested these predictions in a factorial design: males that were handicapped (1 leg removed) and hence vulnerable and control males were paired with females that were more or less aggressive intrinsically (measured toward prey). In mating trials, we recorded the tendency of males to death feign, copulation success, and copulation duration. In addition, we investigated the effect of female mating status (virgin or mated) on these male mating components. Intrinsically aggressive females showed increased mating aggression toward males. Neither female aggressiveness, mating status, nor male vulnerability increased the propensity of males to perform thanatosis. Instead, death-feigning males were more successful in obtaining copulations and gained longer copulations. Hence, our results suggest that thanatosis functions as an adaptive male mating strategy to overcome female resistance. All males were capable of performing thanatosis although some males use it more frequently than others, suggesting a cost of death feigning which maintains the variation in thanatosis during courtship.

Hansen, Line S.; Gonzalez, Sofía F.

2008-01-01

92

Mate choice and uncertainty in the decision process.  

Science.gov (United States)

The behavior of females in search of a mate determines the likelihood that a high quality male is encountered in the search process and alternative search strategies provide different fitness returns to searchers. Models of search behavior are typically formulated on an assumption that the quality of prospective mates is revealed to searchers without error, either directly or by inspection of a perfectly informative phenotypic character. But recent theoretical developments suggest that the relative performance of a search strategy may be sensitive to any uncertainty associated with the to-be-realized fitness benefit of mate choice decisions. Indeed, uncertainty in the decision process is inevitable whenever unobserved male attributes influence the fitness of searchers. In this paper, we derive solutions to the sequential search strategy and the fixed sample search strategy for the general situation in which observed and unobserved male attributes affect the fitness consequences of female mate choice decisions and we determine how the magnitude of various parameters that are influential in the standard models alter these more general solutions. The distribution of unobserved attributes amongst prospective mates determines the uncertainty of mate choice decisions-the reliability of an observed male character as a predictor of male quality-and the realized functional relationship between an observed male character and the fitness return to searchers. The uncertainty of mate choice decisions induced by unobserved male attributes has no influence on the generalized model solutions. Thus, the results of earlier studies of these search models that rely on the use of a perfectly informative male character apply even if an observed male trait does not reveal the quality of prospective mates with certainty. But the solutions are sensitive to any changes of the distribution of unobserved male attributes that alter the realized functional relationship between an observed character and the fitness return to searchers. For example, the standard sequential search model exhibits a reservation property--the acceptability of prospective mates is delimited by a unique threshold criterion--and the existence of this model property under generalized conditions depends critically on the association between the observed and unobserved male characters. In our formulations of the models we assumed that females use a single male character to evaluate the quality of prospective mates, but the model properties generalize to situations in which male quality is evaluated by a direct inspection of multiple male characters. PMID:17942125

Wiegmann, Daniel D; Angeloni, Lisa M

2007-09-02

93

Ondansetron can enhance cisplatin-induced nephrotoxicity via inhibition of multiple toxin and extrusion proteins (MATEs).  

UK PubMed Central (United Kingdom)

The nephrotoxicity limits the clinical application of cisplatin. Human organic cation transporter 2 (OCT2) and multidrug and toxin extrusion proteins (MATEs) work in concert in the elimination of cationic drugs such as cisplatin from the kidney. We hypothesized that co-administration of ondansetron would have an effect on cisplatin nephrotoxicity by altering the function of cisplatin transporters. The inhibitory potencies of ondansetron on metformin accumulation mediated by OCT2 and MATEs were determined in the stable HEK-293 cells expressing these transporters. The effects of ondansetron on drug disposition in vivo were examined by conducting the pharmacokinetics of metformin, a classical substrate for OCTs and MATEs, in wild-type and Mate1-/- mice. The nephrotoxicity was assessed in the wild-type and Mate1-/- mice received cisplatin with and without ondansetron. Both MATEs, including human MATE1, human MATE2-K, and mouse Mate1, and OCT2 (human and mouse) were subject to ondansetron inhibition, with much greater potencies by ondansetron on MATEs. Ondansetron significantly increased tissue accumulation and pharmacokinetic exposure of metformin in wild-type but not in Mate1-/- mice. Moreover, ondansetron treatment significantly enhanced renal accumulation of cisplatin and cisplatin-induced nephrotoxicity which were indicated by increased levels of biochemical and molecular biomarkers and more severe pathohistological changes in mice. Similar increases in nephrotoxicity were caused by genetic deficiency of MATE function in mice. Therefore, the potent inhibition of MATEs by ondansetron enhances the nephrotoxicity associated with cisplatin treatment in mice. Potential nephrotoxic effects of combining the chemotherapeutic cisplatin and the antiemetic 5-hydroxytryptamine-3 (5-HT3) receptor antagonists, such as ondansetron, should be investigated in patients.

Li Q; Guo D; Dong Z; Zhang W; Zhang LK; Huang SM; Polli JE; Shu Y

2013-08-01

94

Associations of beta-catenin alterations and MSI screening status with expression of key cell cycle regulating proteins and survival from colorectal cancer.  

UK PubMed Central (United Kingdom)

BACKGROUND: Despite their pivotal roles in colorectal carcinogenesis, the interrelationship and prognostic significance of beta-catenin alterations and microsatellite instability (MSI) in colorectal cancer (CRC) needs to be further clarified. In this paper, we studied the associations between beta-catenin overexpression and MSI status with survival from CRC, and with expression of p21, p27, cyclin D1 and p53, in a large, prospective cohort study. METHODS: Immunohistochemical MSI-screening status and expression of p21, p27 and p53 was assessed in tissue microarrays with tumours from 557 cases of incident CRC in the Malmö Diet and Cancer Study. Chi Square and Spearman's correlation tests were used to explore the associations between beta-catenin expression, MSI status, clinicopathological characteristics and investigative parameters. Kaplan-Meier analysis and Cox proportional hazards modelling were used to assess the relationship between beta-catenin overexpression, MSI status and cancer specific survival (CSS). RESULTS: Positive MSI screening status was significantly associated with older age, female sex, proximal tumour location, non-metastatic disease, and poor differentiation, and inversely associated with beta-catenin overexpression. Beta-catenin overexpression was significantly associated with distal tumour location, low T-stage and well-differentiated tumours. Patients with MSI tumours had a significantly prolonged CSS in the whole cohort, and in stage III-IV disease, also in multivariable analysis, but not in stage I-II disease. Beta-catenin overexpression was associated with a favourable prognosis in the full cohort and in patients with stage III-IV disease. Neither MSI nor beta-catenin status were predictive for response to adjuvant chemotherapy in curatively treated stage III patients. P53 and p27 expression was positively associated with beta-catenin overexpression and inversely associated with MSI. Cyclin D1 expression was positively associated with MSI and beta-catenin overexpression, and p21 expression was positively associated with MSI but not beta-catenin overexpression. CONCLUSIONS: Findings from this large, prospective cohort study demonstrate that MSI screening status in colorectal cancer is an independent prognostic factor, but not in localized disease, and does not predict response to adjuvant chemotherapy. Beta-catenin overexpression was also associated with favourable outcome but not a treatment predictive factor. Associations of MSI and beta-catenin alterations with other investigative and clinicopathological factors were in line with the expected. VIRTUAL SLIDES: The virtual slides for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/8778585058652609.

Wangefjord S; Brändstedt J; Lindquist KE; Nodin B; Jirström K; Eberhard J

2013-01-01

95

MATE. Multi Aircraft Training Environment  

DEFF Research Database (Denmark)

A medium fidelity and low cost training device for pilots, called the Multi Aircraft Training Environment (MATE), is developed to replace other low fidelity stand-alone training devices and integrate them into a flexible environment, primarily aimed attraining pilots in checklist procedures. The cockpit switches and instruments in MATE are computer-generated graphics. The graphics are back projected onto semi-transparent touch screen panels in a hybrid cockpit mock-up. Thus, the MATE is relativelycheap, it is always available, it is reconfigurable (e.g. between types of aircraft/models to be simulated) and with possibilities for including various forms of intelligent computer assistance. This training concept and the technology are not specific toaviation, but can be used to simulate various types of control panels in different domains. The training effectiveness of pilots' procedure training in the MATE prototype was compared with the effects of traditional training that included the use of realaircraft. The experimental group (EXP) trained the pre-start checklist and the engine start checklist for the Saab 340 commuter aircraft in a MATE prototype. The control group (CTR) trained the same procedures using the aircraft (a/c) for training the prestart and a desktop computer tool (power plant trainer) for training engine starts. Performance on the pre-start checklist was compared in a formal checkout that took place in the a/c. Performance on the engine start procedure was compared in a fullflight simulator (FFS). The conclusion was, firstly, that training in the MATE prototype can result in an equally good performance as the existing training (a/c and computer tools), provided that the MATE trainees are given time to familiarise themselveswith the a/c. Secondly, training in MATE can result in better performance during dynamic tasks, such as abnormal engine starts. This is promising for the further development of the MATE concept.

Hauland, G.; Bove, T.

2002-01-01

96

Phenolic composition of basil plants is differentially altered by plant nutrient status and inoculation with mycorrhizal fungi  

Science.gov (United States)

Quality of basil plants (Ocimum basilicum) used in certain fresh and dry products is a function of its production of secondary metabolites, including phenolic compounds. Nutrient availability, particularly phosphorus (P), can alter plant production of secondary metabolites, and root infection by arb...

97

Assessing the mating 'health' of commercial honey bee queens.  

UK PubMed Central (United Kingdom)

Honey bee queens mate with multiple males, which increases the total genetic diversity within colonies and has been shown to confer numerous benefits for colony health and productivity. Recent surveys of beekeepers have suggested that 'poor queens' are a top management concern, thus investigating the reproductive quality and mating success of commercially produced honey bee queens is warranted. We purchased 80 commercially produced queens from large queen breeders in California and measured them for their physical size (fresh weigh and thorax width), insemination success (stored sperm counts and sperm viability), and mating number (determined by patriline genotyping of worker offspring). We found that queens had an average of 4.37 +/- 1.446 million stored sperm in their spermathecae with an average viability of 83.7 +/- 13.33%. We also found that the tested queens had mated with a high number of drones (average effective paternity frequency: 17.0 +/- 8.98). Queen "quality" significantly varied among commercial sources for physical characters but not for mating characters. These findings suggest that it may be more effective to improve overall queen reproductive potential by culling lower-quality queens rather than systematically altering current queen production practices.

Tarpy DR; Keller JJ; Caren JR; Delaney DA

2012-02-01

98

Big two personality and big three mate preferences: similarity attracts, but country-level mate preferences crucially matter.  

UK PubMed Central (United Kingdom)

People differ regarding their "Big Three" mate preferences of attractiveness, status, and interpersonal warmth. We explain these differences by linking them to the "Big Two" personality dimensions of agency/competence and communion/warmth. The similarity-attracts hypothesis predicts that people high in agency prefer attractiveness and status in mates, whereas those high in communion prefer warmth. However, these effects may be moderated by agentics' tendency to contrast from ambient culture, and communals' tendency to assimilate to ambient culture. Attending to such agentic-cultural-contrast and communal-cultural-assimilation crucially qualifies the similarity-attracts hypothesis. Data from 187,957 online-daters across 11 countries supported this model for each of the Big Three. For example, agentics-more so than communals-preferred attractiveness, but this similarity-attracts effect virtually vanished in attractiveness-valuing countries. This research may reconcile inconsistencies in the literature while utilizing nonhypothetical and consequential mate preference reports that, for the first time, were directly linked to mate choice.

Gebauer JE; Leary MR; Neberich W

2012-12-01

99

Energy status and immune system alterations in Elliptio complanata after ingestion of cyanobacteria Anabaena flos-aquae.  

Science.gov (United States)

Cyanobacteria have often been described as nutritionally poor for herbivorous organisms. To gain additional information on the potential impacts of invertebrates feeding on cyanobacteria, we fed Elliptio complanata mussels with two types of algae: Anabaena flos-aquae (cyanobacteria) and Pseudokirchneriella subcapitata (green algae). Physiological parameters were examined at the energy status, immune system and oxidative stress levels. Energy status was examined by following the rate of electron transport activity in mitochondria (a measure of cellular energy expense) and lipid/sugar stores in the visceral mass. The cyanobacteria were not actively producing toxins. Based on the digestive gland index, the mussels fed equally on either regime. However, the energy status in mussels fed A. flos-aquae revealed that the total sugar was lower in the digestive gland, whereas mitochondrial electron transport activity (MET), once corrected against the digestive gland somatic index, showed increased energy expenses. Acetylcholinesterase activity and lipid peroxidation (LPO) were also higher in mussels fed with A. flos-aquae compared with mussels fed with P. subcapitata. LPO was correlated by mitochondrial activity in both the digestive gland and gills, suggesting that oxidative stress resulted from metabolic respiration. Immunocompetence (phagocytic activity, natural killer cell-like activity, haemocyte count and viability) and humoral level of lysozyme were not affected in mussels by the algae or cyanobacteria regime. Moreover, the xenobiotic conjugating enzyme, glutathione S-transferase, hemoprotein oxidase and vitellogenin-like proteins were not affected in mussel organs via ingestion of A. flos-aquae. Our study suggests that ingestion of cyanobacteria leads to increased energy expenses, oxidative stress and increased acetylcholine turnover in mussels. PMID:23354932

Gélinas, Malorie; Fortier, Marlène; Lajeunesse, André; Fournier, Michel; Gagnon, Christian; Gagné, François

2013-01-26

100

Selenium deficiency in Fisher-344 rats decreases plasma and tissue homocysteine concentrations and alters plasma homocysteine and cysteine redox status.  

Science.gov (United States)

The purpose of the present study was to determine the effect of graded amounts of dietary selenium on plasma and tissue parameters of methionine metabolism including homocysteine. Male weanling Fisher-344 rats (n = 7-8/group) were fed a selenium-deficient, torula yeast-based diet, supplemented with 0 (selenium deficient), 0.02, 0.05 or 0.1 microg (adequate) selenium (as selenite)/g diet. After 61 d, plasma total homocysteine and cysteine were decreased (P < 0.0001) and glutathione increased (P < 0.0001) by selenium deficiency. The concentrations of homocysteine in kidney and heart were decreased (P = 0.02) by selenium deficiency. The activities of liver betaine homocysteine methyltransferase, methionine synthase, S-adenosylmethionine synthase, cystathionine synthase and cystathionase were determined; selenium deficiency affected only betaine homocysteine methyltransferase, which was decreased (P < 0.0001). The ratios of plasma free reduced homocysteine (or cysteine) to free oxidized homocysteine (or cysteine) or to total homocysteine (or cysteine) were increased by selenium deficiency, suggesting that selenium status affects the normally tightly controlled redox status of these thiols. Most differences due to dietary selenium were between rats fed 0 or 0.02 microg selenium/g diet and those fed 0.05 or 0.1 microg selenium/g diet. The metabolic consequences of a marked decrease in plasma homocysteine and smaller but significant decreases in tissue homocysteine are not known. PMID:12042420

Uthus, E O; Yokoi, K; Davis, C D

2002-06-01

 
 
 
 
101

No detectable fertility benefit from a single additional mating in wild stalk-eyed flies.  

UK PubMed Central (United Kingdom)

BACKGROUND: Multiple mating by female insects is widespread, and the explanation(s) for repeated mating by females has been the subject of much discussion. Females may profit from mating multiply through direct material benefits that increase their own reproductive output, or indirect genetic benefits that increase offspring fitness. One particular direct benefit that has attracted significant attention is that of fertility assurance, as females often need to mate multiply to achieve high fertility. This hypothesis has never been tested in a wild insect population. METHODOLOGY/PRINCIPAL FINDINGS: Female Malaysian stalk-eyed flies (Teleopsis dalmanni) mate repeatedly during their lifetime, and have been shown to be sperm limited under both laboratory and field conditions. Here we ask whether receiving an additional mating alleviates sperm limitation in wild females. In our experiment one group of females received a single additional mating, while a control group received an interrupted, and therefore unsuccessful, mating. Females that received an additional mating did not lay more fertilised eggs in total, nor did they lay proportionately more fertilised eggs. Female fertility declined significantly through time, demonstrating that females were sperm limited. However, receipt of an additional mating did not significantly alter the rate of this decline. CONCLUSIONS/SIGNIFICANCE: Our data suggest that the fertility consequences of a single additional mating were small. We discuss this effect (or lack thereof), and suggest that it is likely to be attributed to small ejaculate size, a high proportion of failed copulations, and the presence of X-linked meiotic drive in this species.

Harley E; Fowler K; Cotton S

2010-01-01

102

Caste determination through mating in primitively eusocial societies.  

UK PubMed Central (United Kingdom)

Eusocial animal societies are typified by the presence of a helper (worker) caste which predominantly cares for young offspring in a social group while investing little in their own direct reproduction. A key question is what determines whether an individual becomes a worker or leaves to initiate her own reproduction. In some insects, caste is determined nutritionally during development. In others, and in vertebrate societies, adults are totipotent and the cues that determine caste are less well known. The mate limitation hypothesis (MLH) states that a female's mating status acts as a cue for caste determination: females that mate become reproductives, while those that fail to mate become workers. The MLH is consistent with empirical observations in sweat bees showing that over the course of the nesting season, there are increases in both the proportion of females that become reproductives and the frequency of males in the mating pool. We modelled a foundress's offspring sex-ratio strategy to investigate whether an increasingly male-biased operational sex-ratio over time is evolutionarily stable under the MLH. Our results indicate that such a pattern could occur if early workers were more valuable than late workers. This pattern was then more likely if male mortality was high, if worker mortality was low, if the value of a worker was high and if the period over which workers can help was short. Our results suggest that the MLH can be evolutionarily stable, but only under restrictive conditions. Manipulative experiments are now required to investigate whether mating determines caste in nature.

Lucas ER; Field J

2013-10-01

103

F1 sterility of Diatraea saccharalis (Fab.), Lepidoptera: Crambidae. II. mating dynamics and effects on progeny  

International Nuclear Information System (INIS)

The effect of irradiation of Diatraea saccharalis pupae at substerilizing gamma doses on the competitiveness of adult males emerging from the irradiated pupae and on their sterile progeny was evaluated on the basis of mating dynamics, mating duration and the length of the pre-mating period, as well as the sex ratio and the variation of pupal weights in the progeny. It is concluded that substerilizing gamma doses do not affect the indicators evaluated and that in the progeny the sex ratio is altered in favour of males and F1 pupal weights are reduced significantly. (author). 8 refs, 3 figs, 2 tabs

1993-01-01

104

Altered expression of O-GlcNAc-modified proteins in a mouse model whose glycemic status is controlled by a low carbohydrate ketogenic diet.  

UK PubMed Central (United Kingdom)

Abnormal modification of proteins by O-linked N-acetylglucosamine (O-GlcNAc) is known to be associated with the pathology induced by hyperglycemia. However, the dynamic mechanism of O-GlcNAc modification under hyperglycemic conditions in vivo has not been fully characterized. To understand the mechanism, we established an animal model in which the glycemic status is controlled by the diet. A mutant mouse (ob/ob) which exhibits diet-induced hyperglycemia when fed a regular chow (chow) was used to establish this model; the mice were fed a very low carbohydrate ketogenic diet (KD) to improve hyperglycemia. Using this model, we evaluated the levels of O-GlcNAc-modified proteins in tissues under a hyperglycemic or its improved condition. ELISA and Western blot analyses revealed that altered expression of certain proteins modified by O-GlcNAc were found in the mice tissues, although global O-GlcNAc levels in the tissues remained unaltered by improvement of hyperglycemia. We also found the Akt protein kinase was modified by O-GlcNAc in the liver of ob/ob mice, and the modification levels were decreased by improvement of hyperglycemia. Furthermore, aberrant phosphorylation of Akt was found in the liver of ob/ob mice under hyperglycemic condition. In conclusion, our established mouse model is useful for evaluating the dynamics of O-GlcNAc-modified proteins in tissues associated with glycemic status. This study revealed that the expression level of certain proteins modified by O-GlcNAc is altered when KD improves the hyperglycemia. These proteins could be prospective indexes for nutritional therapy for hyperglycemia-associated diseases, such as diabetes mellitus.

Okuda T; Fukui A; Morita N

2013-11-01

105

Genome-wide hypomethylation in human glioblastomas associated with specific copy number alteration, methylenetetrahydrofolate reductase allele status, and increased proliferation.  

UK PubMed Central (United Kingdom)

Genome-wide reduction in 5-methylcytosine is an epigenetic hallmark of human tumorigenesis. Experimentally induced hypomethylation in mice promotes genomic instability and is sufficient to initiate tumorigenesis. Here, we report that global hypomethylation is common in primary human glioblastomas [glioblastoma multiforme (GBM)] and can affect up to an estimated 10 million CpG dinucleotides per haploid tumor genome. Demethylation involves satellite 2 (Sat2) pericentromeric DNA at chromosomes 1 and 16, the subtelomeric repeat sequence D4Z4 at chromosomes 4q and 10q, and interspersed Alu elements. Severe hypomethylation of Sat2 sequences is associated with copy number alterations of the adjacent euchromatin, suggesting that hypomethylation may be one factor predisposing to specific genetic alterations commonly occurring in GBMs. An additional apparent consequence of global hypomethylation is reactivation of the cancer-testis antigen MAGEA1 via promoter demethylation, but only in GBMs and GBM cell lines exhibiting a 5-methylcytosine content below a threshold of approximately 50%. Primary GBMs with significant hypomethylation tended to be heterozygous or homozygous for the low-functioning Val allele of the rate-limiting methyl group metabolism gene methylenetetrahydrofolate reductase (MTHFR), or had a deletion encompassing this gene at 1p36. Tumors with severe genomic hypomethylation also had an elevated proliferation index and deletion of the MTHFR gene. These data suggest a model whereby either excessive cell proliferation in the context of inadequate methyl donor production from MTHFR deficiency promotes genomic hypomethylation and further genomic instability, or that MTHFR deficiency-associated demethylation leads to increased proliferative activity in GBM.

Cadieux B; Ching TT; VandenBerg SR; Costello JF

2006-09-01

106

Genome-wide hypomethylation in human glioblastomas associated with specific copy number alteration, methylenetetrahydrofolate reductase allele status, and increased proliferation.  

Science.gov (United States)

Genome-wide reduction in 5-methylcytosine is an epigenetic hallmark of human tumorigenesis. Experimentally induced hypomethylation in mice promotes genomic instability and is sufficient to initiate tumorigenesis. Here, we report that global hypomethylation is common in primary human glioblastomas [glioblastoma multiforme (GBM)] and can affect up to an estimated 10 million CpG dinucleotides per haploid tumor genome. Demethylation involves satellite 2 (Sat2) pericentromeric DNA at chromosomes 1 and 16, the subtelomeric repeat sequence D4Z4 at chromosomes 4q and 10q, and interspersed Alu elements. Severe hypomethylation of Sat2 sequences is associated with copy number alterations of the adjacent euchromatin, suggesting that hypomethylation may be one factor predisposing to specific genetic alterations commonly occurring in GBMs. An additional apparent consequence of global hypomethylation is reactivation of the cancer-testis antigen MAGEA1 via promoter demethylation, but only in GBMs and GBM cell lines exhibiting a 5-methylcytosine content below a threshold of approximately 50%. Primary GBMs with significant hypomethylation tended to be heterozygous or homozygous for the low-functioning Val allele of the rate-limiting methyl group metabolism gene methylenetetrahydrofolate reductase (MTHFR), or had a deletion encompassing this gene at 1p36. Tumors with severe genomic hypomethylation also had an elevated proliferation index and deletion of the MTHFR gene. These data suggest a model whereby either excessive cell proliferation in the context of inadequate methyl donor production from MTHFR deficiency promotes genomic hypomethylation and further genomic instability, or that MTHFR deficiency-associated demethylation leads to increased proliferative activity in GBM. PMID:16951158

Cadieux, Benoît; Ching, Tsui-Ting; VandenBerg, Scott R; Costello, Joseph F

2006-09-01

107

Oral administration of a nephrotoxic dose of potassium bromate, a food additive, alters renal redox and metabolic status and inhibits brush border membrane enzymes in rats  

UK PubMed Central (United Kingdom)

The time dependent effect of orally administered KBrO3 on redox status and enzymes of brush border membrane (BBM) and carbohydrate metabolism has been studied in rat kidney. Animals were given a single oral dose of KBrO3 (100mg/kg body weight) and sacrificed at different times after this treatment; control animals were not given KBrO3. The administration of KBrO3 resulted in nephrotoxicity, a decline in the specific activities of several BBM marker enzymes and also induced oxidative stress in kidney. The specific activities of enzymes of carbohydrate metabolism were also altered and suggest a shift in energy metabolism from the aerobic to anaerobic mode. The renal effects of single oral dose of KBrO3 appeared to be reversible; maximum changes in all the parameters were 48h after administration of KBrO3 after which recovery took place, in many cases almost to control values, after 168h. These results suggest that the administration of a single nephrotoxic dose of KBrO3 inhibits brush border membrane enzymes, induces oxidative stress and alters energy metabolism of the renal system in a reversible manner.

Ahmad MK; Naqshbandi A; Fareed M; Mahmood R

2012-09-01

108

Oral administration of a nephrotoxic dose of potassium bromate, a food additive, alters renal redox and metabolic status and inhibits brush border membrane enzymes in rats.  

UK PubMed Central (United Kingdom)

The time dependent effect of orally administered KBrO(3) on redox status and enzymes of brush border membrane (BBM) and carbohydrate metabolism has been studied in rat kidney. Animals were given a single oral dose of KBrO(3) (100mg/kg body weight) and sacrificed at different times after this treatment; control animals were not given KBrO(3). The administration of KBrO(3) resulted in nephrotoxicity, a decline in the specific activities of several BBM marker enzymes and also induced oxidative stress in kidney. The specific activities of enzymes of carbohydrate metabolism were also altered and suggest a shift in energy metabolism from the aerobic to anaerobic mode. The renal effects of single oral dose of KBrO(3) appeared to be reversible; maximum changes in all the parameters were 48 h after administration of KBrO(3) after which recovery took place, in many cases almost to control values, after 168 h. These results suggest that the administration of a single nephrotoxic dose of KBrO(3) inhibits brush border membrane enzymes, induces oxidative stress and alters energy metabolism of the renal system in a reversible manner.

Ahmad MK; Naqshbandi A; Fareed M; Mahmood R

2012-09-01

109

Oral administration of a nephrotoxic dose of potassium bromate, a food additive, alters renal redox and metabolic status and inhibits brush border membrane enzymes in rats.  

Science.gov (United States)

The time dependent effect of orally administered KBrO(3) on redox status and enzymes of brush border membrane (BBM) and carbohydrate metabolism has been studied in rat kidney. Animals were given a single oral dose of KBrO(3) (100mg/kg body weight) and sacrificed at different times after this treatment; control animals were not given KBrO(3). The administration of KBrO(3) resulted in nephrotoxicity, a decline in the specific activities of several BBM marker enzymes and also induced oxidative stress in kidney. The specific activities of enzymes of carbohydrate metabolism were also altered and suggest a shift in energy metabolism from the aerobic to anaerobic mode. The renal effects of single oral dose of KBrO(3) appeared to be reversible; maximum changes in all the parameters were 48 h after administration of KBrO(3) after which recovery took place, in many cases almost to control values, after 168 h. These results suggest that the administration of a single nephrotoxic dose of KBrO(3) inhibits brush border membrane enzymes, induces oxidative stress and alters energy metabolism of the renal system in a reversible manner. PMID:23107716

Ahmad, Mir Kaisar; Naqshbandi, Ashreeb; Fareed, Mohd; Mahmood, Riaz

2012-03-07

110

Functional alteration of a dimeric insecticidal lectin to a monomeric antifungal protein correlated to its oligomeric status.  

UK PubMed Central (United Kingdom)

BACKGROUND: Allium sativum leaf agglutinin (ASAL) is a 25-kDa homodimeric, insecticidal, mannose binding lectin whose subunits are assembled by the C-terminal exchange process. An attempt was made to convert dimeric ASAL into a monomeric form to correlate the relevance of quaternary association of subunits and their functional specificity. Using SWISS-MODEL program a stable monomer was designed by altering five amino acid residues near the C-terminus of ASAL. METHODOLOGY/PRINCIPAL FINDINGS: By introduction of 5 site-specific mutations (-DNSNN-), a ? turn was incorporated between the 11(th) and 12(th) ? strands of subunits of ASAL, resulting in a stable monomeric mutant ASAL (mASAL). mASAL was cloned and subsequently purified from a pMAL-c2X system. CD spectroscopic analysis confirmed the conservation of secondary structure in mASAL. Mannose binding assay confirmed that molecular mannose binds efficiently to both mASAL and ASAL. In contrast to ASAL, the hemagglutination activity of purified mASAL against rabbit erythrocytes was lost. An artificial diet bioassay of Lipaphis erysimi with mASAL displayed an insignificant level of insecticidal activity compared to ASAL. Fascinatingly, mASAL exhibited strong antifungal activity against the pathogenic fungi Fusarium oxysporum, Rhizoctonia solani and Alternaria brassicicola in a disc diffusion assay. A propidium iodide uptake assay suggested that the inhibitory activity of mASAL might be associated with the alteration of the membrane permeability of the fungus. Furthermore, a ligand blot assay of the membrane subproteome of R. solani with mASAL detected a glycoprotein receptor having interaction with mASAL. CONCLUSIONS/SIGNIFICANCE: Conversion of ASAL into a stable monomer resulted in antifungal activity. From an evolutionary aspect, these data implied that variable quaternary organization of lectins might be the outcome of defense-related adaptations to diverse situations in plants. Incorporation of mASAL into agronomically-important crops could be an alternative method to protect them from dramatic yield losses from pathogenic fungi in an effective manner.

Banerjee N; Sengupta S; Roy A; Ghosh P; Das K; Das S

2011-01-01

111

Lactational cadmium exposure induced alterations in the hematological indices and oxidative status in brain, liver and testes of rat pups  

Directory of Open Access Journals (Sweden)

Full Text Available This study was carried out to investigate the effect of lactational exposure to    cadmium (Cd) on suckling male rat pups. Hematological parameters, antioxidant status, some biochemical and pathophysiological indices in brain, liver and testicular tissues of rat offspring were studied. Lactating Sprague–Dawley females received either 0 ppb (control) or 20 ppm Cd as CdCl2 in their drinking water during the lactational period. Suckling male rat pups were weaned and sacrificed on day 24 for performing various biochemical assays. Distortion of the hemopoietic features as decrease in RBCs count, hemoglobin, hematocrit and platelet values were seen in exposed rat pups. Increased lipid peroxidation malondialdehyde (MDA) and depressed antioxidant defense superoxide dimutase (SOD) levels in brain, liver and testes of exposed rat pups were obtained.  Serum activities of alkaline phosphatase (ALP) and lactate dehydrogenase (LDH) showed a significant increase, whereas a reduction in the level of testosterone hormone was obtained in cadmium exposed pups. In addition, Cd induces neuronal degeneration, necrosis in hepatocytes and degeneration in semineferous tubules along with interstitial edema. The previous findings are indicative of multiple targets of cadmium to disrupt several organ functions in newly borne rat pups on lactational exposure.

E. E. Elsharkawy; N.A. El-Nisr

2012-01-01

112

Altered redox status in Escherichia coli cells enhances pyruvate production in pH-adjusting culture with a fermenter.  

UK PubMed Central (United Kingdom)

Improvements in pyruvate production process were examined using Escherichia coli BW25113?pta/pHfdh strain carrying the formate dehydrogenase gene of Mycobacterium vaccae to change the redox status of the cells. Glucose and formate concentrations, and oxygenation levels determined previously in a shake-flask culture were applied for pyruvate production in a 1 l fermenter. However, pyruvate was not produced under the examined conditions. Detailed pH measurements during the fermenter culture using CaCO3 revealed that maintaining the pH value around 6.0 plays an important role in stabilizing the pyruvate accumulation. In the pH-adjusting culture around 6.0 with NaOH solution, the concentration and yield of pyruvate were 8.96 g l(-1) and 0.48 g pyruvate g glucose(-1), respectively, which were significantly higher than the values reported in the shake-flask culture (6.79 g l(-1) and 0.32 g pyruvate g glucose(-1)).

Ojima Y; Matsuo N; Suparman A; Suryadarma P; Taya M

2013-06-01

113

Alterations in promoter methylation status of tumor suppressor HIC1, SFRP2, and DAPK1 genes in prostate carcinomas.  

UK PubMed Central (United Kingdom)

Hypermethylated genomic DNA is a common feature in tumoral tissues, although the prevalence of this modification remains poorly understood. We aimed to determine the frequency of five tumor suppressor (TS) genes in prostate cancer and the correlation between promoter hypermethylation of these genes and low and high grade of prostate carcinomas. A total of 30 prostate tumor specimens were investigated for promoter methylation status of TS hypermethylated in cancer 1 (HIC1), death-associated protein kinase 1 (DAPK1), secreted frizzled-related protein 2 (SFRP2), cyclin-dependent kinase inhibitor 2A (p16), and O-6-methylguanine-DNA methyltransferase (MGMT) genes by using bisulfite modifying method. A high frequency of promoter hypermethylation was found in HIC1 (70.9%), SFRP2 (58.3%), and DAPK1 (33.3%) genes in tumor samples that were examined. The current data show high frequency of hypermethylation changes in HIC1, SFRP2, and DAPK1 genes in prostate carcinomas of high Gleason Score (GS).

Kilinc D; Ozdemir O; Ozdemir S; Korgali E; Koksal B; Uslu A; Gultekin YE

2012-05-01

114

Parent-offspring conflict over mate choice  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Although parental influence over mate choice is important to human mating decisions, it is often overlooked within evolutionary psychology. Based on evolutionary theory, we predict that, while both parents likely influence a child’s mate choice, daughters will perceive having a low quality partner (...

Dubbs, Shelli Lynn,

115

Mate choice decisions by searchers  

Directory of Open Access Journals (Sweden)

Full Text Available For more than two decades rudimentary versions of the fixed sample and sequential search strategies have provided the primary theoretical foundation for the study of mate choice decisions by searchers. The theory that surrounds these models has expanded markedly over this time period. In this paper, we review and extend results derived from these models, with a focus on the empirical analysis of searcher behavior. The basic models are impractical for empirical purposes because they rely on the assumption that searchers—and, for applied purposes, researchers—assess prospective mates based on their quality, the fitness consequences of mate choice decisions. Here we expound versions of the models that are more empirically useful, reformulated to reflect decisions based on male phenotypic characters. For some organisms, it may be possible to use preference functions to derive predictions from the reformulated models and thereby avoid difficulties associated with the measurement of male quality per se. But predictions derived from the two models are difficult to differentiate empirically, regardless of how the models are formulated. Here we develop ideas that illustrate how this goal might be accomplished. In addition, we clarify how the variability of male quality should be evaluated and we extend what is known about how this variability influences searcher behavior under each model. More general difficulties associated with the empirical study of mate choice decisions by searchers are also discussed [Current Zoology 59 (2): 184–199, 2013].

Daniel D. WIEGMANN, Lisa M. ANGELONI, Steven M. SEUBERT, J. Gordon WADE

2013-01-01

116

Sequential mate choice and sexual isolation in threespine stickleback species.  

Science.gov (United States)

Sequential mate choice strategies predict how females should alter their choosiness based on the availability of attractive males. There are many studies on sequential mate choice within species, but few have asked whether females apply these strategies to interactions between species and how these strategies may affect hybridization. We tested how previous interactions with conspecific and heterospecific males affect mate preference and sexual isolation in two threespine stickleback species (benthics and limnetics: Gasterosteus spp.). Consistent with previous work, we found that within species, stickleback females gauge male attractiveness relative to previously encountered males. If females extend these decision rules between species, we predicted that previous interactions with conspecifics should make heterospecifics less attractive, whereas interactions with heterospecifics should make conspecifics more attractive. However, females found heterospecifics less attractive after prior experience, largely independent of the species of male first encountered. Thus, sequential mate choice strategies are used within but not between species in sticklebacks. Further, learning from prior courtship interactions acts to enhance existing sexual isolation between species. PMID:23194003

Kozak, G M; Head, M L; Lackey, A C R; Boughman, J W

2012-11-29

117

Sequential mate choice and sexual isolation in threespine stickleback species.  

UK PubMed Central (United Kingdom)

Sequential mate choice strategies predict how females should alter their choosiness based on the availability of attractive males. There are many studies on sequential mate choice within species, but few have asked whether females apply these strategies to interactions between species and how these strategies may affect hybridization. We tested how previous interactions with conspecific and heterospecific males affect mate preference and sexual isolation in two threespine stickleback species (benthics and limnetics: Gasterosteus spp.). Consistent with previous work, we found that within species, stickleback females gauge male attractiveness relative to previously encountered males. If females extend these decision rules between species, we predicted that previous interactions with conspecifics should make heterospecifics less attractive, whereas interactions with heterospecifics should make conspecifics more attractive. However, females found heterospecifics less attractive after prior experience, largely independent of the species of male first encountered. Thus, sequential mate choice strategies are used within but not between species in sticklebacks. Further, learning from prior courtship interactions acts to enhance existing sexual isolation between species.

Kozak GM; Head ML; Lackey AC; Boughman JW

2013-01-01

118

Alteration of Isocitrate Dehydrogenase Following Acute Ischemic Injury as a Means to Improve Cellular Energetic Status in Neuroadaptation.  

Science.gov (United States)

The isocitrate dehydrogenase (IDH) enzymes were initially identified as essential components of the Krebs cycle. IDH mutations were thought to be incompatible with cell survival. However, 90% of glioblastomas were recently shown to be associated with somatic mutations in these enzymes, indicating a possible role for IDH in promoting cellular survival in hypoxic environments. Our proteomic analysis of rats given 10 minutes of middle cerebral artery occlusion to induce transient ischemia demonstrates a significant decrease in IDH expression. We have recapitulated this decrease in an in vitro model using primary cortical neurons exposed to acute oxygen and glucose deprivation. Given the role of IDHs in energy metabolism and antioxidant production, we hypothesize that the IDHs may serve as first-line, rapid-response enzymes that regulate survival in environments of energetic or oxidative stress. In order to identify the specific events that regulate IDH enzymes, HT-22 neural cells were subjected to either a selective energetic challenge or a pure oxidative stress. In response to the non-lethal energetic challenge induced by substituting galactose for glucose, we observed increased IDH1, 2, and 3 expression and cessation of cellular proliferation. No change in expression of any IDH isoform was observed when neural cells were subjected to subtoxic oxidative stress via glutathione depletion. Taken together, these data imply that IDH expression rapidly responds to changes in energetic status, but not to oxidative stress. These data also suggest that IDH enzymes respond not only to allosteric modulation, but can also change patterns of expression in response to moderate stress in an effort to maximize ATP production and survival. PMID:23469839

Grelli, K N; Palubinsky, A M; Kale, A C; Lizama-Manibusan, B N; Stankowski, J N; Milne, G L; Singer, R; McLaughlin, B

2013-02-27

119

Alteration of Isocitrate Dehydrogenase Following Acute Ischemic Injury as a Means to Improve Cellular Energetic Status in Neuroadaptation.  

UK PubMed Central (United Kingdom)

The isocitrate dehydrogenase (IDH) enzymes were initially identified as essential components of the Krebs cycle. IDH mutations were thought to be incompatible with cell survival. However, 90% of glioblastomas were recently shown to be associated with somatic mutations in these enzymes, indicating a possible role for IDH in promoting cellular survival in hypoxic environments. Our proteomic analysis of rats given 10 minutes of middle cerebral artery occlusion to induce transient ischemia demonstrates a significant decrease in IDH expression. We have recapitulated this decrease in an in vitro model using primary cortical neurons exposed to acute oxygen and glucose deprivation. Given the role of IDHs in energy metabolism and antioxidant production, we hypothesize that the IDHs may serve as first-line, rapid-response enzymes that regulate survival in environments of energetic or oxidative stress. In order to identify the specific events that regulate IDH enzymes, HT-22 neural cells were subjected to either a selective energetic challenge or a pure oxidative stress. In response to the non-lethal energetic challenge induced by substituting galactose for glucose, we observed increased IDH1, 2, and 3 expression and cessation of cellular proliferation. No change in expression of any IDH isoform was observed when neural cells were subjected to subtoxic oxidative stress via glutathione depletion. Taken together, these data imply that IDH expression rapidly responds to changes in energetic status, but not to oxidative stress. These data also suggest that IDH enzymes respond not only to allosteric modulation, but can also change patterns of expression in response to moderate stress in an effort to maximize ATP production and survival.

Grelli KN; Palubinsky AM; Kale AC; Lizama-Manibusan BN; Stankowski JN; Milne GL; Singer R; McLaughlin B

2013-02-01

120

LOSS of Mrp1 alters detoxification enzyme expression in a tissue- and hormonal-status-specific manner.  

UK PubMed Central (United Kingdom)

The multidrug resistance-associated protein1 (MRP1/ABCC1) is a member of the ABCC transporter subfamily that mediates the efflux of pharmaceuticals, xenobiotics and steroid hormones, typically as glutathione, glucuronide or sulfate conjugates. Since loss of one transporter can be compensated by increasing the expression of other transporters and conjugation enzymes, we sought to examine compensatory changes in phase I, II and III enzyme expression in extrahepatic tissues, including the kidney, lungs and small intestine of intact or castrated Mrp1(-/-) male mice. In the kidney, the expression of several P450s, sulfotransferase 1a1 (Sult), glucuronosyltransferases (Ugt) and Mrps2-4, were significantly changed owing to castration alone. The only time genotype mattered was between the castrated FVB and Mrp1 knockout mice. In contrast, expression of the Ugts, Sult 1a1 and Mrp3 in the lungs was significantly downregulated in the Mrp1 knockout mice, so based exclusively on genotype. In the small intestine, there were interactions between steroid hormone levels and genotype, as the expression differences were only found in mice lacking Mrp1, and were changed between intact and castrated animals. The mechanism behind this pattern of expression may be to due to Nrf2 regulation, as its expression mirrors that of the phase II and phase III enzymes. These results indicate that compensatory responses owing to the loss of Mrp1 vary dramatically, depending on the particular tissue. This information will aid in the understanding of how drug uptake, disposition and elimination can be influenced by both hormone status and the presence and magnitude of transporter expression.

Sivils JC; Ancrum TM; Bain LJ

2013-08-01

 
 
 
 
121

LOSS of Mrp1 alters detoxification enzyme expression in a tissue- and hormonal-status-specific manner.  

Science.gov (United States)

The multidrug resistance-associated protein1 (MRP1/ABCC1) is a member of the ABCC transporter subfamily that mediates the efflux of pharmaceuticals, xenobiotics and steroid hormones, typically as glutathione, glucuronide or sulfate conjugates. Since loss of one transporter can be compensated by increasing the expression of other transporters and conjugation enzymes, we sought to examine compensatory changes in phase I, II and III enzyme expression in extrahepatic tissues, including the kidney, lungs and small intestine of intact or castrated Mrp1(-/-) male mice. In the kidney, the expression of several P450s, sulfotransferase 1a1 (Sult), glucuronosyltransferases (Ugt) and Mrps2-4, were significantly changed owing to castration alone. The only time genotype mattered was between the castrated FVB and Mrp1 knockout mice. In contrast, expression of the Ugts, Sult 1a1 and Mrp3 in the lungs was significantly downregulated in the Mrp1 knockout mice, so based exclusively on genotype. In the small intestine, there were interactions between steroid hormone levels and genotype, as the expression differences were only found in mice lacking Mrp1, and were changed between intact and castrated animals. The mechanism behind this pattern of expression may be to due to Nrf2 regulation, as its expression mirrors that of the phase II and phase III enzymes. These results indicate that compensatory responses owing to the loss of Mrp1 vary dramatically, depending on the particular tissue. This information will aid in the understanding of how drug uptake, disposition and elimination can be influenced by both hormone status and the presence and magnitude of transporter expression. PMID:22522787

Sivils, Jeffrey C; Ancrum, Tiffany M; Bain, Lisa J

2012-04-23

122

c-Kit/PDGFRA gene status alterations possibly related to primary imatinib resistance in gastrointestinal stromal tumors.  

UK PubMed Central (United Kingdom)

PURPOSE: To correlate morphologic changes with molecular, biochemical, and cytogenetic profiles in gastrointestinal stromal tumor (GIST) patients before and after imatinib treatment. EXPERIMENTAL DESIGN: We investigated 132 tumor samples obtained from 35 patients with advanced disease who underwent resective surgery after imatinib treatment according to the European Organization for Research and Treatment of Cancer-Soft Tissue and Bone Sarcoma Group protocol. On the basis of imaging findings, 27 patients were responders and 8 progressors, and retaining this radiological subdivision, we analyzed posttreatment morphologic changes correlating them with molecular, biochemical, and cytogenetic analyses. RESULTS: On the basis of morphology (residual viable cellularity/proliferation markers), three subgroups were identified showing high, moderate, or low response. All of the progressing cases clustered in the low-response subgroup, whereas the responding cases were distributed in all three subgroups. The correlation between morphology and the molecular findings showed that secondary mutations segregated with the low-response subgroup, whereas c-Kit primary resistance mutations were randomly distributed in the three subgroups. Fluorescence in situ hybridization analysis of c-Kit/PDGFRA genes showed that all of the progressing cases were disomic. Referring to morphology, among the responding cases, a disomic pattern was mainly restricted to the high responders, whereas the moderate and low responders were aneusomic. Comparison of post-imatinib genomic profiles with the 23 available primary tumors showed that 17 cases carried the same cytogenetic pattern. Overall, 12 of the 27 primary tumors presented a gain/loss of c-Kit/PDGFRA gene copy number. CONCLUSIONS: Our findings show that c-Kit/PDGFRA genomic alterations were present at disease onset in 1/3 of the examined cases. They therefore represent an early event possibly related to primary imatinib resistance in GISTs.

Miselli FC; Casieri P; Negri T; Orsenigo M; Lagonigro MS; Gronchi A; Fiore M; Casali PG; Bertulli R; Carbone A; Pierotti MA; Tamborini E; Pilotti S

2007-04-01

123

Congenital hypothyroidism alters the oxidative status, enzyme activities and morphological parameters in the hippocampus of developing rats.  

Science.gov (United States)

Congenital hypothyroidism is associated with delay in cell migration and proliferation in brain tissue, impairment of synapse formation, misregulation of neurotransmitters, hypomyelination and mental retardation. However, the mechanisms underlying the neuropsychological deficits observed in congenital hypothyroidism are not completely understood. In the present study we proposed a mechanism by which hypothyroidism leads to hippocampal neurotoxicity. Congenital hypothyroidism induces c-Jun-N-terminal kinase (JNK) pathway activation leading to hyperphosphorylation of the glial fibrillary acidic protein (GFAP), vimentin and neurofilament subunits from hippocampal astrocytes and neurons, respectively. Moreover, hyperphosphorylation of the cytoskeletal proteins was not reversed by T3 and poorly reversed by T4. In addition, congenital hypothyroidism is associated with downregulation of astrocyte glutamate transporters (GLAST and GLT-1) leading to decreased glutamate uptake and subsequent influx of Ca(2+) through N-methyl-D-aspartate (NMDA) receptors. The Na(+)-coupled (14)C-?-methyl-amino-isobutyric acid ((14)C-MeAIB) accumulation into hippocampal cells also might cause an increase in the intracellular Ca(2+) concentration by opening voltage-dependent calcium channels (VDCC). The excessive influx of Ca(2+) through NMDA receptors and VDCCs might lead to an overload of Ca(2+) within the cells, which set off glutamate excitotoxicity and oxidative stress. The inhibited acetylcholinesterase (AChE) activity might also induce Ca(2+) influx. The inhibited glucose-6-phosphate dehydrogenase (G6PD) and gamma-glutamyl transferase (GGT) activities, associated with altered glutamate and neutral amino acids uptake could somehow affect the GSH turnover, the antioxidant defense system, as well as the glutamate-glutamine cycle. Reduced levels of S100B and glial fibrillary acidic protein (GFAP) take part of the hypothyroid condition, suggesting a compromised astroglial/neuronal neurometabolic coupling which is probably related to the neurotoxic damage in hypothyroid brain. PMID:23693027

Cattani, Daiane; Goulart, Paola Bez; Cavalli, Vera Lúcia de Liz Oliveira; Winkelmann-Duarte, Elisa; Dos Santos, André Quincozes; Pierozan, Paula; de Souza, Daniela Fraga; Woehl, Viviane Mara; Fernandes, Marilda C; Silva, Fátima Regina Mena Barreto; Gonçalves, Carlos Alberto; Pessoa-Pureur, Regina; Zamoner, Ariane

2013-05-18

124

Congenital hypothyroidism alters the oxidative status, enzyme activities and morphological parameters in the hippocampus of developing rats.  

UK PubMed Central (United Kingdom)

Congenital hypothyroidism is associated with delay in cell migration and proliferation in brain tissue, impairment of synapse formation, misregulation of neurotransmitters, hypomyelination and mental retardation. However, the mechanisms underlying the neuropsychological deficits observed in congenital hypothyroidism are not completely understood. In the present study we proposed a mechanism by which hypothyroidism leads to hippocampal neurotoxicity. Congenital hypothyroidism induces c-Jun-N-terminal kinase (JNK) pathway activation leading to hyperphosphorylation of the glial fibrillary acidic protein (GFAP), vimentin and neurofilament subunits from hippocampal astrocytes and neurons, respectively. Moreover, hyperphosphorylation of the cytoskeletal proteins was not reversed by T3 and poorly reversed by T4. In addition, congenital hypothyroidism is associated with downregulation of astrocyte glutamate transporters (GLAST and GLT-1) leading to decreased glutamate uptake and subsequent influx of Ca(2+) through N-methyl-D-aspartate (NMDA) receptors. The Na(+)-coupled (14)C-?-methyl-amino-isobutyric acid ((14)C-MeAIB) accumulation into hippocampal cells also might cause an increase in the intracellular Ca(2+) concentration by opening voltage-dependent calcium channels (VDCC). The excessive influx of Ca(2+) through NMDA receptors and VDCCs might lead to an overload of Ca(2+) within the cells, which set off glutamate excitotoxicity and oxidative stress. The inhibited acetylcholinesterase (AChE) activity might also induce Ca(2+) influx. The inhibited glucose-6-phosphate dehydrogenase (G6PD) and gamma-glutamyl transferase (GGT) activities, associated with altered glutamate and neutral amino acids uptake could somehow affect the GSH turnover, the antioxidant defense system, as well as the glutamate-glutamine cycle. Reduced levels of S100B and glial fibrillary acidic protein (GFAP) take part of the hypothyroid condition, suggesting a compromised astroglial/neuronal neurometabolic coupling which is probably related to the neurotoxic damage in hypothyroid brain.

Cattani D; Goulart PB; Cavalli VL; Winkelmann-Duarte E; Dos Santos AQ; Pierozan P; de Souza DF; Woehl VM; Fernandes MC; Silva FR; Gonçalves CA; Pessoa-Pureur R; Zamoner A

2013-08-01

125

Parental control over mate choice to prevent marriages with out-group members: a study among mestizos, Mixtecs, and Blacks in Mexico.  

UK PubMed Central (United Kingdom)

The present research examined how a preference for influencing the mate choice of one's offspring is associated with opposition to out-group mating among parents from three ethnic groups in the Mexican state of Oaxaca: mestizos (people of mixed descent, n = 103), indigenous Mixtecs (n = 65), and blacks (n = 35). Nearly all of the men in this study were farmworkers or fishermen. Overall, the level of preferred parental influence on mate choice was higher than in Western populations, but lower than in Asian populations. Only among the Mixtecs were fathers more in favor of parental influence on the mate choice of children than mothers were. As predicted, opposition to out-group mating was an important predictor of preferred parental influence on mate choice, more so among fathers than among mothers, especially in the mestizo group-the group with the highest status. In addition, women, and especially mestizo women, expressed more opposition to out-group mating than men did.

Buunk AP; Pollet TV; Dubbs S

2012-09-01

126

Infección por Chlamydia trachomatis en varones y su asociación con las alteraciones ginecológicas de su compañera sexual/ Chlamydia trachomatis infection in men and its association to gynecologic alterations of his sexual mate  

Scientific Electronic Library Online (English)

Full Text Available Abstract in spanish Objetivo. Determinar la frecuencia de infección por Chlamydia trachomatis y comparar la información clínica y el estilo de vida de varones con y sin infección por este patógeno, así como su asociación con las alteraciones ginecológicas que presenta su compañera sexual en un grupo de parejas que asisten a la Clínica de Infertilidad del Instituto Nacional de Perinatologia de la Ciudad de México. Métodos. Se realizó un estudio abierto, longitudinal y prospectivo (more) en un grupo de parejas con diagnóstico de infertilidad, que fueron tratadas en el Instituto Nacional de Perinatologia durante el periodo de junio del 2000 a abril del 2001. Se recolectaron muestras uretrales y cervicales de cada pareja para el diagnóstico de C. trachomatis mediante la prueba de hibridación en fase líquida (PACE-2). También se recolectaron muestras de semen para el análisis de espermatobioscopia y se hicieron cultivos microbiológicos de rutina a las muestras cervicales y de semen. Los datos microbiológicos, clínicos y ginecológicos de los participantes fueron comparados por %z, el análisis de tendencia para proporciones fue usado para establecer el nivel de riesgo en las variables (RR). Las diferencias fueron consideradas estadísticamente significativas si p Abstract in english Objective.To determinate the frequency of Chlamydia trachomatis infection in male partners of infertile couples who attend to the infertility clinic at Instituto Nacional de Perinatologia, as well as to compare the clinical data and lifestyle between C. trachomatis-inifected and uninfected men to establish a possible association with gynecological damage in their sexual female partners. Methods. An open prospective study was performed in infertile couples, whose follow up (more) was carried out at Instituto Nacional de Perinatologia between June 2000 and April 2001. Urethral and cervical swabs were obtained from each couple and the specimens were subjected to a C. trachomatis-specific liquid-phase hibridization test (PACE-2) and routine microbiological analysis. Semen analysis were also included. A relative risk (RR) test was done to analyze variables and square chi test was used to analize clinical and gynecological data from female partners and data from semen examination. Statistical differences were considered as significant when the p value was below 0.05. Results. C. trachomatis active infection was found in 14 out of 384 urethral swabs (3.6%). No significant alterations were observed in semen samples of C. trachomatis-infected men, as compared to non-infected individuals. Microbiological analyses of semen showed a significant isolation o/Mycoplasma sp (RR = 5.87, IC95% 1.4-24.7). Eight out of fourteen female partners of C. trachomatis-infected men were also infected with C. trachomatis (RR= 10.57, IC95% 5.67-19.7), Candida albicans was other pathogen isolated from 8/14 of those women (RR = 1.89, IC95% 1.17-3.05). Gynecological and obstetrical associations found among female partners of C. trachomatis-infected men were as follows: tubal adhesions in 10/14 (RR = 1.54, IC95% 1.08-2.18), salpingitis in 2/14 (RR = 2.2), history of ectopic pregnancies in 11/14 (RR =2.94, IC95% 1.01-8.53) and abnormal pregnancy loss in 9/14 (RR = 1.5). Conclusion. A low prevalence of C. trachomatis infection was observed among male partners of infertile couples as compared with other reports, but this discrepancy could be attributable to the specimen collection and diagnostic assay used. Otherwise, this data suggests that a chronic pathogen's antigenic stimulation may result in an increased formation of tubal adhesions and/or in ectopic pregnancies among female partners of C. trachomatis-infected individuals. Thus, preventive and control measures must be introduced into men's healthcare services, through laboratory and clinical examination, since these subjects are the main reservoirs of C trachomatis.

Guerra-Infante, Fernando M; Tapia-Yáñez, J. Ramón; López-Hurtado, Marcela; Flores-Medina, Saúl; Díaz-García, Francisco J

2005-06-01

127

Mating behavior of Diabrotica speciosa (Coleoptera: Chrysomelidae).  

UK PubMed Central (United Kingdom)

Diabrotica speciosa (Germar) is an economically important pest of Neotropical cultures and represents a quarantine risk for Neartic and Paleartic Regions. Despite its agricultural importance, few studies have been done on mating behavior and chemical communication, which has delayed the development of behavioral techniques for population management, such as the use of pheromone traps. In this study, we determined 1) the age at first mating; 2) diel rhythm of matings; 3) number of matings over 7 d; 4) the sequence of D. speciosa activities during premating, mating, and postmating; 5) the duration of each activity; and 6) response to male and female conspecific volatiles in Y-tube olfactometer. The first mating occurred between the third and seventh day after adult emergence and the majority of pairs mated on the fourth day after emergence. Pairs of D. speciosa showed a daily rhythm of mating with greater sexual activity between the end of the photophase and the first half of the scotophase. During the 7 d of observation, most pairs mated only once, although 30% mated two, three, or four times. In a Y-tube olfactometer, males were attracted by virgin females as well as by the volatile compounds emitted by females. Neither males nor their volatiles were attractive to either sex. Our observation provide information about mating behavior of D. speciosa, which will be useful in future research in chemical communication, such as identification of the pheromone and development of management techniques for this species using pheromone traps.

Nardi C; Luvizotto RA; Parra JR; Bento JM

2012-06-01

128

Mating behavior of Diabrotica speciosa (Coleoptera: Chrysomelidae).  

Science.gov (United States)

Diabrotica speciosa (Germar) is an economically important pest of Neotropical cultures and represents a quarantine risk for Neartic and Paleartic Regions. Despite its agricultural importance, few studies have been done on mating behavior and chemical communication, which has delayed the development of behavioral techniques for population management, such as the use of pheromone traps. In this study, we determined 1) the age at first mating; 2) diel rhythm of matings; 3) number of matings over 7 d; 4) the sequence of D. speciosa activities during premating, mating, and postmating; 5) the duration of each activity; and 6) response to male and female conspecific volatiles in Y-tube olfactometer. The first mating occurred between the third and seventh day after adult emergence and the majority of pairs mated on the fourth day after emergence. Pairs of D. speciosa showed a daily rhythm of mating with greater sexual activity between the end of the photophase and the first half of the scotophase. During the 7 d of observation, most pairs mated only once, although 30% mated two, three, or four times. In a Y-tube olfactometer, males were attracted by virgin females as well as by the volatile compounds emitted by females. Neither males nor their volatiles were attractive to either sex. Our observation provide information about mating behavior of D. speciosa, which will be useful in future research in chemical communication, such as identification of the pheromone and development of management techniques for this species using pheromone traps. PMID:22732614

Nardi, C; Luvizotto, R A; Parra, J R P; Bento, J M S

2012-06-01

129

Female-borne cues affecting Psyttalia concolor (Hymenoptera: Braconidae) male behavior during courtship and mating.  

UK PubMed Central (United Kingdom)

Knowledge of the mechanisms that regulate courtship and mating behavior in Psyttalia concolor (Szépligeti)-a koinobiont endophagous solitary parasitoid of the olive fruit fly, Bactrocera oleae (Rossi), and of other fruit flies-is essential to its mass rearing and management. Augmentative releases of P. concolor for olive fruit fly control started in the Mediterranean areas in the 1950s and still continue with limited success. We determined the influence of visual and chemical cues on courtship and mating behavior of this braconid and the possible effect of the mating status of males and females in the perception of these cues. Our results suggest that integration of visual and chemical stimuli are fundamental for mate location and courtship. Indeed, the optimal response of the male was achieved when physical and chemical cues were simultaneously presented and vision and olfaction worked synergistically.

Canale A; Benelli G; Lucchi A

2013-06-01

130

Altered relationship between protonmotive force and respiration rate in non-phosphorylating liver mitochondria isolated from rats of different thyroid hormone status.  

UK PubMed Central (United Kingdom)

We have determined the relationship between rate of respiration and protonmotive force in oligomycin-inhibited liver mitochondria isolated from euthyroid, hypothyroid and hyperthyroid rats. Respiration rate was titrated with the respiratory-chain inhibitor malonate. At any given respiration rate mitochondria isolated from hypothyroid rats had a protonmotive force greater than mitochondria isolated from euthyroid controls, and mitochondria isolated from hyperthyroid rats had a protonmotive force less than mitochondria isolated from euthyroid controls. In the absence of malonate mitochondrial respiration rate increased in the order hypothyroid less than euthyroid less than hyperthyroid, while protonmotive force increased in the order hyperthyroid less than euthyroid less than hypothyroid. These findings are consistent with a thyroid-hormone-induced increase in the proton conductance of the inner mitochondrial membrane or a decrease in the H+/O ratio of the respiratory chain at any given protonmotive force. Thus the altered proton conductance or H+/O ratio of mitochondria isolated from rats of different thyroid hormone status controls the respiration rate required to balance the backflow of protons across the inner mitochondrial membrane. We discuss the possible relevance of these findings to the control of state 3 and state 4 respiration by thyroid hormone.

Hafner RP; Nobes CD; McGown AD; Brand MD

1988-12-01

131

Mating duration and sperm precedence in the spider Linyphia triangularis  

DEFF Research Database (Denmark)

In many animal species, mating behaviour is highly ritualised, which may allow us to relate some of its consequences, e.g. male paternity and female receptivity, to the progression of phases in the mating sequence; at the same time, ritualisation raises the question of to what extent the partners, especially the males, are able to influence the outcome of mating for their own benefit. We studied the linyphiid spider Linyphia triangularis in which mating follows a strict sequence during which the male inducts two droplets of sperm and transfers them to the female. We performed sperm competition experiments (sterile-male technique) including four treatments, in which the copulation of the first male was interrupted at prescribed phases of the mating sequence, while the second male was allowed a complete mating. Second males spent a shorter time than first males on the behaviours prior to sperm transfer, but the amount of sperm (2 droplets) and the time spent in sperm transfer were independent of the females’ mating status. The proportion of females accepting the second male depended on the mating duration of the first male, i.e. whether the first male had transferred one or two sperm droplets. After a complete first mating, most females accepted no further males. A last-male sperm precedence was apparent if only half of the first sperm droplet had been transferred by the first male, but this switched to a first male precedence if one full sperm droplet had been transferred. Thus, even in the face of sperm competition, it is sufficient for the first male to transfer one sperm droplet. The second sperm droplet and the extended copulatory courtship associated with its transfer may serve to induce a lack of receptivity in the female, but the males seem unable to enhance their reproductive success through variable copulatory tactics.

Weldingh, Ditte L.; Toft, SØren

2011-01-01

132

Mating order-dependent female mate choice in the polygynandrous common lizard Lacerta vivipara.  

UK PubMed Central (United Kingdom)

Recent studies indicate that directional female mate choice and order-dependent female mate choice importantly contribute to non-random mating patterns. In species where females prefer larger sized males, disentangling different hypotheses leading to non-random mating patterns is especially difficult, given that male size usually correlates with behaviours that may lead to non-random mating (e.g. size-dependent emergence from hibernation, male fighting ability). Here we investigate female mate choice and order-dependent female mate choice in the polygynandrous common lizard (Lacerta vivipara). By sequentially presenting males in random order to females, we exclude non-random mating patterns potentially arising due to intra-sexual selection (e.g. male-male competition), trait-dependent encounter probabilities, trait-dependent conspicuousness, or trait-dependent emergence from hibernation. To test for order-dependent female mate choice we investigate whether the previous mating history affects female choice. We show that body size and body condition of the male with which a female mated for the first time were bigger and better, respectively, than the average body size and body condition of the rejected males. There was a negative correlation between body sizes of first and second copulating males. This indicates that female mate choice is dependent on the previous mating history and it shows that the female's choice criteria are non-static, i.e. non-directional. Our study therefore suggests that context-dependent female mate choice may not only arise due to genotype-environment interactions, but also due to other female mating strategies, i.e. order-dependent mate choice. Thus context-dependent female mate choice might be more frequent than previously thought.

Fitze PS; Cote J; Clobert J

2010-02-01

133

Mating order-dependent female mate choice in the polygynandrous common lizard Lacerta vivipara.  

Science.gov (United States)

Recent studies indicate that directional female mate choice and order-dependent female mate choice importantly contribute to non-random mating patterns. In species where females prefer larger sized males, disentangling different hypotheses leading to non-random mating patterns is especially difficult, given that male size usually correlates with behaviours that may lead to non-random mating (e.g. size-dependent emergence from hibernation, male fighting ability). Here we investigate female mate choice and order-dependent female mate choice in the polygynandrous common lizard (Lacerta vivipara). By sequentially presenting males in random order to females, we exclude non-random mating patterns potentially arising due to intra-sexual selection (e.g. male-male competition), trait-dependent encounter probabilities, trait-dependent conspicuousness, or trait-dependent emergence from hibernation. To test for order-dependent female mate choice we investigate whether the previous mating history affects female choice. We show that body size and body condition of the male with which a female mated for the first time were bigger and better, respectively, than the average body size and body condition of the rejected males. There was a negative correlation between body sizes of first and second copulating males. This indicates that female mate choice is dependent on the previous mating history and it shows that the female's choice criteria are non-static, i.e. non-directional. Our study therefore suggests that context-dependent female mate choice may not only arise due to genotype-environment interactions, but also due to other female mating strategies, i.e. order-dependent mate choice. Thus context-dependent female mate choice might be more frequent than previously thought. PMID:19779935

Fitze, Patrick S; Cote, Julien; Clobert, Jean

2009-09-25

134

Covariation and repeatability of male mating effort and mating preferences in a promiscuous fish.  

UK PubMed Central (United Kingdom)

Although mate choice by males does occur in nature, our understanding of its importance in driving evolutionary change remains limited compared with that for female mate choice. Recent theoretical models have shown that the evolution of male mate choice is more likely when individual variation in male mating effort and mating preferences exist and positively covary within populations. However, relatively little is known about the nature of such variation and its maintenance within natural populations. Here, using the Trinidadian guppy (Poecilia reticulata) as a model study system, we report that mating effort and mating preferences in males, based on female body length (a strong correlate of fecundity), positively covary and are significantly variable among subjects. Individual males are thus consistent, but not unanimous, in their mate choice. Both individual mating effort (including courtship effort) and mating preference were significantly repeatable. These novel findings support the assumptions and predictions of recent evolutionary models of male mate choice, and are consistent with the presence of additive genetic variation for male mate choice based on female size in our study population and thus with the opportunity for selection and further evolution of large female body size through male mate choice.

Godin JG; Auld HL

2013-07-01

135

Covariation and repeatability of male mating effort and mating preferences in a promiscuous fish.  

Science.gov (United States)

Although mate choice by males does occur in nature, our understanding of its importance in driving evolutionary change remains limited compared with that for female mate choice. Recent theoretical models have shown that the evolution of male mate choice is more likely when individual variation in male mating effort and mating preferences exist and positively covary within populations. However, relatively little is known about the nature of such variation and its maintenance within natural populations. Here, using the Trinidadian guppy (Poecilia reticulata) as a model study system, we report that mating effort and mating preferences in males, based on female body length (a strong correlate of fecundity), positively covary and are significantly variable among subjects. Individual males are thus consistent, but not unanimous, in their mate choice. Both individual mating effort (including courtship effort) and mating preference were significantly repeatable. These novel findings support the assumptions and predictions of recent evolutionary models of male mate choice, and are consistent with the presence of additive genetic variation for male mate choice based on female size in our study population and thus with the opportunity for selection and further evolution of large female body size through male mate choice. PMID:23919148

Godin, Jean-Guy J; Auld, Heather L

2013-05-31

136

A character demonstrating the occurrence of mating in male Cactoblastis cactorum (Lepidoptera: Pyralidae)  

International Nuclear Information System (INIS)

[en] The reproductive system of adult male Cactoblastis cactorum, the cactus moth, was examined to determine whether the mating status of males could be ascertained. In unmated males, the posterior portion of the primary ductus ejaculatorius simplex is opaque yellow in color and contains many small football-shaped hyaline granules 3-5 x 5-10 ?m in size. In mated males, the posterior simplex is clear and contains no granules. The presence or absence of these characters was found to be highly reliable and should be of value in determining mating status in marked-recaptured males of this species in a sterile insect release program directed against Cactoblastis. (author)

2007-01-01

137

A novel mating approach for genetic algorithms.  

UK PubMed Central (United Kingdom)

Genetic algorithms typically use crossover, which relies on mating a set of selected parents. As part of crossover, random mating is often carried out. A novel approach to parent mating is presented in this work. Our novel approach can be applied in combination with a traditional similarity-based criterion to measure distance between individuals or with a fitness-based criterion. We introduce a parameter called the mating index that allows different mating strategies to be developed within a uniform framework: an exploitative strategy called best-first, an explorative strategy called best-last, and an adaptive strategy called self-adaptive. Self-adaptive mating is defined in the context of the novel algorithm, and aims to achieve a balance between exploitation and exploration in a domain-independent manner. The present work formally defines the novel mating approach, analyzes its behavior, and conducts an extensive experimental study to quantitatively determine its benefits. In the domain of real function optimization, the experiments show that, as the degree of multimodality of the function at hand grows, increasing the mating index improves performance. In the case of the self-adaptive mating strategy, the experiments give strong results for several case studies.

Galán SF; Mengshoel OJ; Pinter R

2013-01-01

138

Variation in human mate choice: simultaneously investigating heritability, parental influence, sexual imprinting, and assortative mating.  

Science.gov (United States)

Human mate choice is central to individuals' lives and to the evolution of the species, but the basis of variation in mate choice is not well understood. Here we looked at a large community-based sample of twins and their partners and parents ([Formula: see text] individuals) to test for genetic and family environmental influences on mate choice, while controlling for and not controlling for the effects of assortative mating. Key traits were analyzed, including height, body mass index, age, education, income, personality, social attitudes, and religiosity. This revealed near-zero genetic influences on male and female mate choice over all traits and no significant genetic influences on mate choice for any specific trait. A significant family environmental influence was found for the age and income of females' mate choices, possibly reflecting parental influence over mating decisions. We also tested for evidence of sexual imprinting, where individuals acquire mate-choice criteria during development by using their opposite-sex parent as the template of a desirable mate; there was no such effect for any trait. The main discernible pattern of mate choice was assortative mating; we found that partner similarity was due to initial choice rather than convergence and also at least in part to phenotypic matching. PMID:21508607

Zietsch, Brendan P; Verweij, Karin J H; Heath, Andrew C; Martin, Nicholas G

2011-05-01

139

Variation in human mate choice: simultaneously investigating heritability, parental influence, sexual imprinting, and assortative mating.  

UK PubMed Central (United Kingdom)

Human mate choice is central to individuals' lives and to the evolution of the species, but the basis of variation in mate choice is not well understood. Here we looked at a large community-based sample of twins and their partners and parents ([Formula: see text] individuals) to test for genetic and family environmental influences on mate choice, while controlling for and not controlling for the effects of assortative mating. Key traits were analyzed, including height, body mass index, age, education, income, personality, social attitudes, and religiosity. This revealed near-zero genetic influences on male and female mate choice over all traits and no significant genetic influences on mate choice for any specific trait. A significant family environmental influence was found for the age and income of females' mate choices, possibly reflecting parental influence over mating decisions. We also tested for evidence of sexual imprinting, where individuals acquire mate-choice criteria during development by using their opposite-sex parent as the template of a desirable mate; there was no such effect for any trait. The main discernible pattern of mate choice was assortative mating; we found that partner similarity was due to initial choice rather than convergence and also at least in part to phenotypic matching.

Zietsch BP; Verweij KJ; Heath AC; Martin NG

2011-05-01

140

Status Epilepticus Triggers Early And Late Alterations In Brain-Derived Neurotrophic Factor And Nmda Glutamate Receptor Grin2b Dna Methylation Levels In The Hippocampus.  

UK PubMed Central (United Kingdom)

Status epilepticus (SE) triggers abnormal expression of genes in the hippocampus, such as glutamate receptor subunit epsilon-2 (Grin2b/Nr2b) and brain-derived neurotrophic factor (Bdnf), that is thought to occur in temporal lobe epilepsy (TLE). We examined the underlying DNA methylation mechanisms and investigated whether these mechanisms contribute to the expression of these gene targets in the epileptic hippocampus. Experimental TLE was provoked by kainic acid-induced SE. Bisulfite sequencing analysis revealed increased Grin2b/Nr2b and decreased Bdnf DNA methylation levels that corresponded to decreased Grin2b/Nr2b and increased Bdnf mRNA and protein expression in the epileptic hippocampus. Blockade of DNA methyltransferase (DNMT) activity with zebularine decreased global DNA methylation levels and reduced Grin2b/Nr2b, but not Bdnf, DNA methylation levels. Interestingly, we found that DNMT blockade further decreased Grin2b/Nr2b mRNA expression whereas GRIN2B protein expression increased in the epileptic hippocampus, suggesting that a posttranscriptional mechanism may be involved. Using chromatin immunoprecipitation analysis we found that DNMT inhibition restored the decreases in AP2alpha transcription factor levels at the Grin2b/Nr2b promoter in the epileptic hippocampus. DNMT inhibition increased field excitatory postsynaptic potential in hippocampal slices isolated from epileptic rats. EEG monitoring confirmed that DNMT inhibition did not significantly alter disease course, but promoted the latency to seizure onset or SE. Thus, DNA methylation may be an early event triggered by SE that persists late into the epileptic hippocampus to contribute to gene expression changes in TLE.

Ryley Parrish R; Albertson AJ; Buckingham SC; Hablitz JJ; Mascia KL; Davis Haselden W; Lubin FD

2013-06-01

 
 
 
 
141

Mating enhances the probability of winning aggressive encounters in male lobster cockroaches.  

UK PubMed Central (United Kingdom)

In the present study, we report that contact with isolated female antenna significantly increases both the pheromone 3-hydroxy-2-butanone (3H-2B) release and the hemolymph JH III level in all examined aggressive posture-adopting (AP) and NP (non-AP-adopting) socially naïve males, with significantly faster concomitant pre-mating wing-raising behavior in AP as compared to NP males. 3H-2B release and JH III level were significantly increased after mating in both AP and NP males. A positive correlation was observed between mating experience and dominant status. Furthermore, mated-AP males initiated fights more rapidly and fought for a significantly longer duration than mated-NP males; retention with the paired female for 24h did not affect this increase. JH III level and 3H-2B release were significantly increased in dominant males as compared to subordinates. These results suggest that prior mating experience in invertebrates may enhance aggression in subsequent male-male encounters, with accompanying physiological (hormone and pheromone) responses.

Kou R; Hsu CC

2013-08-01

142

LjMATE1: a citrate transporter responsible for iron supply to the nodule infection zone of Lotus japonicus.  

UK PubMed Central (United Kingdom)

Symbiotic nitrogen fixation by intracellular rhizobia within legume root nodules requires the exchange of nutrients between host plant cells and their resident bacteria. While exchanged molecules imply nitrogen compounds, carbohydrates and also various minerals, knowledge of the molecular basis of plant transporters that mediate those metabolite exchanges is still limited. In this study, we have shown that a multidrug and toxic compound extrusion (MATE) protein, LjMATE1, is specifically induced during nodule formation, which nearly paralleled nodule maturation, in a model legume Lotus japonicus. Reporter gene experiments indicated that the expression of LjMATE1 was restricted to the infection zone of nodules. To characterize the transport function of LjMATE1, we conducted a biochemical analysis using a heterologous expression system, Xenopus oocytes, and found that LjMATE1 is a specific transporter for citrate. The physiological role of LjMATE1 was analyzed after generation of L. japonicus RNA interference (RNAi) lines. One RNAi knock-down line revealed limited growth under nitrogen-deficient conditions with inoculation of rhizobia compared with the controls (the wild type and an RNAi line in which LjMATE1 was not suppressed). It was noteworthy that Fe localization was clearly altered in nodule tissues of the knock-down line. These results strongly suggest that LjMATE1 is a nodule-specific transporter that assists the translocation of Fe from the root to nodules by providing citrate.

Takanashi K; Yokosho K; Saeki K; Sugiyama A; Sato S; Tabata S; Ma JF; Yazaki K

2013-04-01

143

Functions, diversity, and evolution of traumatic mating.  

Science.gov (United States)

Copulation can involve the wounding of the mating partner by specialised devices. This type of mating, which we term traumatic mating, has been regarded as exceptional. Its prevalence, however, has not been compared across taxa, nor have its functions and putative evolutionary pathways. A categorisation has been lacking to date. We here show that traumatic mating is a widespread and diverse phenomenon that likely evolved via several pathways. Its putative functions include: (i) anchorage during mating; (ii) stimulation of short-term female reproductive investment; (iii) male paternity advantages; and (iv) enhanced fertilisation efficiency in transitions to internal fertilisation. Both natural and sexual selection have likely contributed to the parallel evolution of traumatic intromittent organs in phylogenetically distant taxa. These organs are sometimes remarkably similar in shape and often, but not always, inject sperm. The target sites of trauma infliction and the nature of secretions delivered alongside sperm are thus far poorly studied, but data on both are needed to elucidate the function of traumatic mating. The few existing studies that explicitly quantify fitness impacts of traumatic mating indicate that this strategy may often be costly to the party being wounded. However, a comprehensive approach to assess overall investments and returns for both sexes is a major target for future work. Finally, for the first time, we corroborate quantitatively the hypothesis that traumatic mating evolved relatively more often among hermaphroditic than among gonochoric taxa. PMID:23347274

Lange, Rolanda; Reinhardt, Klaus; Michiels, Nico K; Anthes, Nils

2013-01-25

144

The genetic architecture of house fly mating behavior.  

Science.gov (United States)

This chapter summarizes several experimental approaches used to identify the effects of dominance, epistasis, and genotype-by-environment interactions in the genetic architecture of the mating behavior of the common house fly (Musca domestica L.). Quantitative genetic investigations of mating behavior hold special intrigue for unraveling the complexities of fitness traits, with applications to theory on sexual selection and speciation. Besides being well suited to large-scale quantitative genetic protocols, the house fly has a remarkably complex courtship repertoire, affording special opportunities for studies on communication, social interactions, and learning. Increased additive genetic variances for the courtship repertoire of experimentally bottlenecked populations provided evidence for the presence of dominance and/or epistasis. Negative genetic variances in these populations suggested genotype-by-environment interactions, where the environment is the mating partner. Line cross assays of populations that had been subjected to selection for divergent courtship repertoire confirmed that both dominance and epistasis have significant effects. These crosses also showed more directly that the expression of the male's genotype is dependent upon the preferences of his mating partner. Repeatability studies also detailed how males alter their courtship performances with successive encounters within and across females, such that the males learn to improve their techniques in securing copulations. A review of 41 animal behavior studies found that a wide range of traits and taxa have dominance, epistasis, and genotype-y-environment interactions, although house fly courtship may remain a unique model where learning is an intersexually selected trait. Future development of more sophisticated molecular techniques for the M. domestica genome will help unravel the underlying biochemical and developmental pathways of these quantitative genetic interactions for a more complete understanding of the processes of inbreeding depression, outbreeding depression, and pleiotropy. PMID:15797454

Meffert, Lisa M; Hagenbuch, Kara L

2005-01-01

145

Low mate encounter rate increases male risk taking in a sexually cannibalistic praying mantis.  

UK PubMed Central (United Kingdom)

Male praying mantises are forced into the ultimate trade-off of mating versus complete loss of future reproduction if they fall prey to a female. The balance of this trade-off will depend both on (1) the level of predatory risk imposed by females and (2) the frequency of mating opportunities for males. We report the results of a set of experiments that examine the effects of these two variables on male risk-taking behavior and the frequency of sexual cannibalism in the praying mantis Tenodera sinensis. We experimentally altered the rate at which males encountered females and measured male approach and courtship behavior under conditions of high and low risk of being attacked by females. We show that male risk taking depends on prior access to females. Males with restricted access to females showed greater risk-taking behavior. When males were given daily female encounters, they responded to greater female-imposed risk by slowing their rate of approach and remained a greater distance from a potential mate. In contrast, males without recent access to mates were greater risk-takers; they approached females more rapidly and to closer proximity, regardless of risk. In a second experiment, we altered male encounter rate with females and measured rates of sexual cannibalism when paired with hungry or well-fed females. Greater risk-taking behavior by males with low mate encounter rates resulted in high rates of sexual cannibalism when these males were paired with hungry females.

Brown WD; Muntz GA; Ladowski AJ

2012-01-01

146

Female mate fidelity in a Lek mating system and its implications for the evolution of cooperative lekking behavior.  

UK PubMed Central (United Kingdom)

The extent and importance of female mate fidelity in polygynous mating systems are poorly known. Fidelity may contribute to high variance in male reproductive success when it favors attractive mates or may stabilize social interactions if females are faithful to mating sites rather than males. Using 12 years of data on genetic mate choice in the cooperatively lekking lance-tailed manakin (Chiroxiphia lanceolata), I investigated the frequency of fidelity within and between years, whether females were faithful to individual males or to mating sites across years, and whether fidelity favored attractive males. Mate fidelity occurred in 41.7% of 120 between-year comparisons and was observed for 41.1% of 73 individual females that had the opportunity to mate faithfully. Females were not more likely to mate at prior mating sites when previous mates were replaced. Faithful females mated with the same male in up to four consecutive years but were not disproportionately faithful to attractive partners. Mating history influences current mate choice, and fidelity in this lekking system apparently represents active mate choice by females but little is not cited in the text. Please provide a citation or mark this reference for deletion.consensus in mate choices among faithful females. This study underscores the prevalence of mate fidelity in polygynous mating systems and emphasizes the need to consider the larger context of lifetime reproductive behavior when interpreting patterns of female choice.

DuVal EH

2013-02-01

147

The best timing of mate search in Armadillidium vulgare (Isopoda, Oniscidea).  

UK PubMed Central (United Kingdom)

Mate choice is mediated by many components with the criteria varying across the animal kingdom. Chemical cues used for mate attractiveness can also reflect mate quality. Regarding the gregarious species Armadillidium vulgare (isopod crustacean), we tested whether individuals can discriminate conspecifics at two different levels (between sex and physiological status) based on olfactory perception. Tested conspecifics were individuals of the same or opposite sex, with the females at different moult stages. We found that the attractiveness of individuals was mediated by short-distance chemical cues and tested individuals were able to discriminate and prefer individuals of the opposite sex. Moreover, male preference to female increased during their moulting status as they matured. Males were particularly more attracted by females with appearing white calcium plates, which corresponds to the beginning of their higher receptivity period. These differences in attractiveness due to sex and physiological status are likely to shape the composition of aggregates and facilitate mate finding and optimize the reproductive success for both males and females. Thus aggregation pheromones could be linked to sex pheromones in terrestrial isopods.

Beauché F; Richard FJ

2013-01-01

148

The best timing of mate search in Armadillidium vulgare (Isopoda, Oniscidea).  

Science.gov (United States)

Mate choice is mediated by many components with the criteria varying across the animal kingdom. Chemical cues used for mate attractiveness can also reflect mate quality. Regarding the gregarious species Armadillidium vulgare (isopod crustacean), we tested whether individuals can discriminate conspecifics at two different levels (between sex and physiological status) based on olfactory perception. Tested conspecifics were individuals of the same or opposite sex, with the females at different moult stages. We found that the attractiveness of individuals was mediated by short-distance chemical cues and tested individuals were able to discriminate and prefer individuals of the opposite sex. Moreover, male preference to female increased during their moulting status as they matured. Males were particularly more attracted by females with appearing white calcium plates, which corresponds to the beginning of their higher receptivity period. These differences in attractiveness due to sex and physiological status are likely to shape the composition of aggregates and facilitate mate finding and optimize the reproductive success for both males and females. Thus aggregation pheromones could be linked to sex pheromones in terrestrial isopods. PMID:23469225

Beauché, Fanny; Richard, Freddie-Jeanne

2013-03-01

149

Podisus nigrispinus requer cópulas longas para o sucesso reprodutivo/ Podisus nigrispinus (Dallas) (Hemiptera: Pentatomidae) requires long matings for successful reproduction  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese A realização de múltiplas e longas cópulas parece ser importante para a reprodução de percevejos predadores como Podisus nigrispinus (Dallas), mas o comportamento governando essas características permanece desconhecido. Neste estudo foram investigados o comportamento de cópula e a reprodução de P. nigrispinus em função do tamanho do macho, seu status prévio de acasalamento, risco de predação e interrupção de cópulas. A escolha da fêmea para o acasalamen (more) to foi estudada sob múltipla escolha, parcial ou sem chance de escolha por machos grandes ou pequenos. O comportamento para o início do acasalamento e tempo de cópula sob risco de predação quando na presença de Polistes versicolor Oliver foi comparado àquele de casais sem risco de predação. Machos e fêmeas de P. nigrispinus acasalaram independentemente do tamanho e status prévio de acasalamento dos machos, além de não apresentarem preferência por parceiros. A duração da cópula, escolha do parceiro e fertilidade das fêmeas não foram influenciadas pelo tamanho do macho, nem a presença do predador alterou o comportamento de acasalamento e duração de cópula. Fêmeas com cópulas interrompidas após 30, 60, 120 e 240 min apresentaram baixa viabilidade de ovos (0; 3,1; 7,7 e 34%, respectivamente), enquanto aquelas com tempo natural de cópula (338 a 671 min) obtiveram 74,2% de viabilidade. Portanto, o sucesso reprodutivo de P. nigrispinus não depende do tamanho do macho ou de seu status de acasalamento, mas requer longas cópulas para a transferência de espermatozóides. Abstract in english The occurrence of multiple and long matings seem to play an important role in the reproduction of the predatory stinkbugs such as Podisus nigrispinus (Dallas). However, the mechanisms underlying these behaviors remain unclear. In this study, the reproduction of P. nigrispinus was investigated as function of females' choice for their mating pair based on male body size and previous mating status, risk of predation and duration of mating. The female mating behavior was stud (more) ied with female having multiple, partial or no partner choice based on male body size. Time to initiate a mating and its duration was observed after pairing males and females under risk of predation imposed by the presence of the predatory wasp Polistes versicolor Oliver. In addition, aiming to determine the reasons for long lasting matings, female had their mating interrupted at different intervals. Our data indicated that P. nigrispinus females do not select male partners as function of their body size and mating status. Duration of mating, mating partners' choice, and female fecundity and fertility were not influenced by the male size and risk of predation imposed by the predatory wasps. Mating interrupted after 30, 60, 120 and 240 min resulted in only 0, 3.1, 7.7 and 34% of egg hatching compared to 74.2% under uninterrupted mating (338 to 671 min long). Therefore, the reproductive success of P. nigrispinus females does not depend on male size and male mating status, but requires long-lasting mating as a condition for adequate spermatozoa transference to females instead.

Rodrigues, Agna R S; Torres, Jorge B; Siqueira, Herbert A A; Teixeira, Valéria W

2009-12-01

150

Courtship and mating of Scorpiops luridus Zhu Lourenço & Qi, 2005 (Scorpiones: Euscorpiidae) from Xizang province, China  

Directory of Open Access Journals (Sweden)

Full Text Available In the current work, the courtship and mating of Scorpiops luridus Zhu Lourenço & Qi, 2005 (Euscorpiidae) from Xizang province (Tibet), China, were studied for the first time in the laboratory. Most of the mating behaviors in Scorpiops luridus are not remarkably different from those exhibited by other scorpions. However, for the first time a male pulling a female with its chelicerae to rapidly accomplish the sperm uptake was observed. Additionally, the sexual stinging behavior displayed by the male occurred in the initial stage, not during the promenade stage as previously described in several scorpion species. Through observation and analysis, we speculate that venom injection during sexual stinging is selective, possibly relying on the status shown by the stung scorpion (passive or aggressive). In order to clearly describe the process of courtship and mating, both sequences are represented in a flow chart, while the main behavior components of these processes were identified, analyzed and discussed.

GB Jiao; MS Zhu

2010-01-01

151

The effect of mate removal on dawn singing behaviour in male pied bush chats  

Directory of Open Access Journals (Sweden)

Full Text Available To determine the influence of pairing status on dawn singing behaviour in pied bush chats Saxicola caprata, we conducted mate removal experiments across eight territories. The experiment was divided into three stages: pre-removal (pairs were present on their respective territories), removal (females were experimentally removed), and returned (females were released into the focal pairs’ territories). Dawn bout length, song rate, song complexity, percentage performance time, song perch height, and distance of singing location to territory boundary were measured for each male during each experimental stage. We did not find an effect of mate removal on any dawn song characteristics of male pied bush chats suggesting that the presence or absence of a mate does not influence male dawn singing behaviour. Our findings further suggest that males use dawn chorus to mediate social relationships with neighbouring males to proclaim an established territory [Current Zoology 57 (1): 72–76, 2011].

Vinaya Kumar SETHI, Dinesh BHATT, Amit KUMAR

2011-01-01

152

Courtship and mating of Scorpiops luridus Zhu Lourenço & Qi, 2005 (Scorpiones: Euscorpiidae) from Xizang province, China  

Scientific Electronic Library Online (English)

Full Text Available Abstract in english In the current work, the courtship and mating of Scorpiops luridus Zhu Lourenço & Qi, 2005 (Euscorpiidae) from Xizang province (Tibet), China, were studied for the first time in the laboratory. Most of the mating behaviors in Scorpiops luridus are not remarkably different from those exhibited by other scorpions. However, for the first time a male pulling a female with its chelicerae to rapidly accomplish the sperm uptake was observed. Additionally, the sexual stinging be (more) havior displayed by the male occurred in the initial stage, not during the promenade stage as previously described in several scorpion species. Through observation and analysis, we speculate that venom injection during sexual stinging is selective, possibly relying on the status shown by the stung scorpion (passive or aggressive). In order to clearly describe the process of courtship and mating, both sequences are represented in a flow chart, while the main behavior components of these processes were identified, analyzed and discussed.

Jiao, GB; Zhu, MS

2010-01-01

153

Mating system instability in Schiedea menziesii (Caryophyllaceae).  

Science.gov (United States)

We investigated inbreeding depression and selfing in hermaphroditic Schiedea menziesii to assess the stability of the breeding system. A combination of high selfing rates and strong inbreeding depression suggests that the mating system is unstable. The population-level selfing rate measured in three years ranged considerably from 0.425 (SE = 0.138) to 0.704 (0.048); family measures of selfing rate varied from zero to one in all three years. Inbreeding coefficients did not differ from zero, suggesting that inbred plants do not survive to reproduction in the field. Average inbreeding depression measured in two greenhouse experiments was 0.608-0.870, with values for individual plants ranging from -0.170 to 0.940. The magnitude of inbreeding depression expressed at different life-history stages depended on experimental conditions. When plants were grown during the winter, inbreeding depression was expressed at early and late life-history stages. When plants were grown during the summer, inbreeding depression was detected for germination but not for later life-history stages. Inbreeding depression for vegetative and inflorescence biomass was also measured using field-collected seeds where cross status was assigned using genotypes determined electrophoretically. We did not detect a relation between inbreeding depression and the selfing rate at the level of the individual plant. We saw no evidence for intrafloral selfing, suggesting that the evolution of increased selfing through autogamy is unlikely, despite high selfing rates. A more likely outcome of breeding system instability is the evolution of gynodioecy, which occurs in species of Schiedea closely related to S. menziesii. Females have been detected in progeny of S. menziesii that have been raised in the greenhouse. In the absence of biotic pollen vectors, the failure of these females to establish in the natural population may result from the absence of adaptations for wind pollination. PMID:12353750

Rankin, Anne E; Weller, Stephen G; Sakai, Ann K

2002-08-01

154

Mating system instability in Schiedea menziesii (Caryophyllaceae).  

UK PubMed Central (United Kingdom)

We investigated inbreeding depression and selfing in hermaphroditic Schiedea menziesii to assess the stability of the breeding system. A combination of high selfing rates and strong inbreeding depression suggests that the mating system is unstable. The population-level selfing rate measured in three years ranged considerably from 0.425 (SE = 0.138) to 0.704 (0.048); family measures of selfing rate varied from zero to one in all three years. Inbreeding coefficients did not differ from zero, suggesting that inbred plants do not survive to reproduction in the field. Average inbreeding depression measured in two greenhouse experiments was 0.608-0.870, with values for individual plants ranging from -0.170 to 0.940. The magnitude of inbreeding depression expressed at different life-history stages depended on experimental conditions. When plants were grown during the winter, inbreeding depression was expressed at early and late life-history stages. When plants were grown during the summer, inbreeding depression was detected for germination but not for later life-history stages. Inbreeding depression for vegetative and inflorescence biomass was also measured using field-collected seeds where cross status was assigned using genotypes determined electrophoretically. We did not detect a relation between inbreeding depression and the selfing rate at the level of the individual plant. We saw no evidence for intrafloral selfing, suggesting that the evolution of increased selfing through autogamy is unlikely, despite high selfing rates. A more likely outcome of breeding system instability is the evolution of gynodioecy, which occurs in species of Schiedea closely related to S. menziesii. Females have been detected in progeny of S. menziesii that have been raised in the greenhouse. In the absence of biotic pollen vectors, the failure of these females to establish in the natural population may result from the absence of adaptations for wind pollination.

Rankin AE; Weller SG; Sakai AK

2002-08-01

155

Influence of Nutritional Flushing Prior to Mating on the Performance of West African Dwarf Goats Mated in the Rainy Season  

Directory of Open Access Journals (Sweden)

Full Text Available The effect of nutritional flushing for a period of six weeks prior to mating on the physical condition, serum metabolic and hormonal status at mating and litter size at birth of 32 pluriparous West African Dwarf (WAD) goats was studied using a 2 x 2 factorial design. The factors in the design were age (young, 3-4 years old versus old, 5-6 years old) and nutritional flushing regime (pasture alone versus pasture plus concentrate supplementation). The young does gained more weight and body condition (2.0±0.30 kg; 0.53±0.10 units; p>0.05) over the 6-wk nutritional flushing period than the old does (1.4±0.30 kg; 0.40±0.10 units), but the old does were heavier (p0.05) between treatments. The serum glucose concentrations were also similar for the treatment groups and averaged 2.6±0.10 mmol/l at mating. At the end of the nutritional flushing period, supplemented does had a higher (pIU/ml) than the unsupplemented does. Young does also had higher (pIU/ml) than old does (14.3±0.63 IU/ml). Serum Luteinizing Hormone (LH) concentration at mating was similar for supplemented and unsupplemented does, but was higher (pIU/ml) than for old does (1.8±0.23 IU/ml). Young does had a higher litter size (1.81±0.12) than old does (1.50±0.12) and supplemented does had a larger litter (1.81±0.12) than the unsupplemented does (1.50±0.12). These differences were, however, not statistically significant (p>0.05). There was, however, an interaction between age of doe and nutritional flushing treatment with young does that were supplemented having a mean (±SE) litter size of 2.13±0.18 compared to 1.50±0.18 for each of the other three treatment groups. It was concluded that young (3-4 years old) does may benefit from concentrate supplementation of wet season grazing, but that old does (5-6 years old) will not benefit from this supplementation if they are in moderate body condition six weeks before mating.

P.K. Karikari; E.Y. Blasu

2009-01-01

156

Mating frequency in Apis mellifera iberiensis queens.  

UK PubMed Central (United Kingdom)

Honey bees exhibit high levels of polyandry. This mating behaviour provides high levels of genetic diversity within the colonies which increases colony productivity, queen fitness and resistance to diseases. We investigated the mating frequency in two Iberian populations of Apis mellifera iberiensis, one from northern Spain inhabiting the Cantabrian Mountains and showing west European (M) mitochondrial haplotypes, the other located in south-eastern Spain close to the Mediterranean Sea and bearing African (A) mitochondrial DNA. Queens of the northern apiaries mated with 8 - 25 drones (average 15.73 ± 4.58), those of the south-eastern with 10 - 29 drones (average 18.92 ± 5.07), a difference that was significant (p = 0.036). Genetic relatedness among workers was 0.30 ± 0.02 in both populations. It is discussed whether climatic conditions and genetic background may influence honey bee queen mating behaviour.

Hernandez-Garcia Raquel; Rua Pilardela; Serrano Jose

2009-01-01

157

Associations between body morphology, mating success and mate preferences among Slovak males and females.  

Science.gov (United States)

Human body morphology is thought to be correlated with sexual behaviour and sociosexuality (defined as an increased willingness to engage in sex without commitment) influences the perception of certain cues of physical attractiveness. Based on a sample of Slovak university students, we investigated relationships between 1) male and female mating success and reported body morphology (body mass index, BMI and waist-to-hip ratio, WHR) and 2) mate preference characteristics and mating success. Both males and females reported a similar number of long-term sexual partners and frequency of engaging in extra-pair copulation (EPC). The mating success of both sexes was positively mediated by self-perceived attractiveness. However, female BMI was inversely associated with mating success whereas increasing BMI was positively associated with male mating success (the total number of lifetime sexual partners) as well as with the likelihood of engaging in EPC. Unrestricted sociosexuality positively correlated with direct and indirect benefits from mating and negatively with the religious/political background of a potential mate and with the desire for a home/ children. These results confirm the hypothesis that human body morphology is associated with sexual behaviour and that cues of direct/indirect benefits in a potential mate positively correlate with sociosexuality. PMID:23980387

Prokop, Pavol; Fedor, Peter

2013-01-01

158

Associations between body morphology, mating success and mate preferences among Slovak males and females.  

UK PubMed Central (United Kingdom)

Human body morphology is thought to be correlated with sexual behaviour and sociosexuality (defined as an increased willingness to engage in sex without commitment) influences the perception of certain cues of physical attractiveness. Based on a sample of Slovak university students, we investigated relationships between 1) male and female mating success and reported body morphology (body mass index, BMI and waist-to-hip ratio, WHR) and 2) mate preference characteristics and mating success. Both males and females reported a similar number of long-term sexual partners and frequency of engaging in extra-pair copulation (EPC). The mating success of both sexes was positively mediated by self-perceived attractiveness. However, female BMI was inversely associated with mating success whereas increasing BMI was positively associated with male mating success (the total number of lifetime sexual partners) as well as with the likelihood of engaging in EPC. Unrestricted sociosexuality positively correlated with direct and indirect benefits from mating and negatively with the religious/political background of a potential mate and with the desire for a home/ children. These results confirm the hypothesis that human body morphology is associated with sexual behaviour and that cues of direct/indirect benefits in a potential mate positively correlate with sociosexuality.

Prokop P; Fedor P

2013-01-01

159

Antioxidant activity of polyphenols from green and toasted mate tea.  

UK PubMed Central (United Kingdom)

The production and distribution of toasted mate tea in Brazil has increased, which has resulted in its greater consumption. Mate tea is obtained by roasting non-fermented erva-mate in order to produce toasted erva-mate or toasted mate tea. However, although the product is much appreciated, studies of its chemical composition and the concentration of polyphenols, particularly flavonols present in toasted mate tea, are few and often controversial. This paper elucidates some misunderstandings involving the nomenclature of erva-mate and toasted mate, and mainly provides an overview of the composition of polyphenols and antioxidant capacity of toasted mate tea and its raw material, erva-mate, in comparison with other teas, the compositions of which were found in the literature.

Coentrão Pde A; Teixeira VL; Netto AD

2011-05-01

160

The role of pheromone receptors for communication and mating in Hypocrea jecorina (Trichoderma reesei).  

UK PubMed Central (United Kingdom)

Discovery of sexual development in the ascomycete Trichoderma reesei (Hypocrea jecorina) as well as detection of a novel class of peptide pheromone precursors in this fungus indicates promising insights into its physiology and lifestyle. Here we investigated the role of the two pheromone receptors HPR1 and HPR2 in the H. jecorina pheromone-system. We found that these pheromone receptors show an unexpectedly high genetic variability among H. jecorina strains. HPR1 and HPR2 confer female fertility in their cognate mating types (MAT1-1 or MAT1-2, respectively) and mediate induction of fruiting body development. One compatible pheromone precursor-pheromone receptor pair (hpr1-hpp1 or hpr2-ppg1) in mating partners was sufficient for sexual development. Additionally, pheromone receptors were essential for ascospore development, hence indicating their involvement in post-fertilisation events. Neither pheromone precursor genes nor pheromone receptor genes of H. jecorina were transcribed in a strictly mating type dependent manner, but showed enhanced expression levels in the cognate mating type. In the presence of a mating partner under conditions favoring sexual development, transcript levels of pheromone precursors were significantly increased, while those of pheromone receptor genes do not show this trend. In the female sterile T. reesei strain QM6a, transcriptional responses of pheromone precursor and pheromone receptor genes to a mating partner were clearly altered compared to the female fertile wild-type strain CBS999.97. Consequently, a delayed and inappropriate response to the mating partner may be one aspect causing female sterility in QM6a.

Seibel C; Tisch D; Kubicek CP; Schmoll M

2012-10-01

 
 
 
 
161

Mating compatibility among four pest members of the Bactrocera dorsalis fruit fly species complex (Diptera: Tephritidae).  

UK PubMed Central (United Kingdom)

Bactrocera dorsalis (Hendel), Bactrocera papayae Drew & Hancock, Bactrocera philippinensis Drew & Hancock, and Bactrocera carambolae Drew & Hancock are pest members within the B. dorsalis species complex of tropical fruit flies. The species status of these taxa is unclear and this confounds quarantine, pest management, and general research. Mating studies carried out under uniform experimental conditions are required as part of resolving their species limits. These four taxa were collected from the wild and established as laboratory cultures for which we subsequently determined levels of prezygotic compatibility, assessed by field cage mating trials for all pair-wise combinations. We demonstrate random mating among all pair-wise combinations involving B. dorsalis, B. papayae, and B. philippinensis. B. carambolae was relatively incompatible with each of these species as evidenced by nonrandom mating for all crosses. Reasons for incompatibility involving B. carambolae remain unclear; however, we observed differences in the location of couples in the field cage for some comparisons. Alongside other factors such as pheromone composition or other courtship signals, this may lead to reduced interspecific mating compatibility with B. carambolae. These data add to evidence that B. dorsalis, B. papayae, and B. philippinensis represent the same biological species, while B. carambolae remains sufficiently different to maintain its current taxonomic identity. This poses significant implications for this group's systematics, impacting on pest management, and international trade.

Schutze MK; Jessup A; Ul-Haq I; Vreysen MJ; Wornoayporn V; Vera MT; Clarke AR

2013-04-01

162

Both mating types of the wheat pathogen Mycosphaerella graminicola are present in Morocco.  

Science.gov (United States)

Septoria tritici blotch caused by the heterothallic ascomycete Mycosphaerella graminicola is one of the most currently damaging diseases on wheat crops worldwide. So far, no information was reported about the status of sexual reproduction of this pathogen under Moroccan conditions. We investigated here for the first time the occurrence of the two mating types (MAT1-1 and MAT1-2) of M. graminicola in Morocco by sampling 141 single-conidial isolates from 4 important wheat producing regions (Gharb, Saïs, Chaouia and Tadla). The mating type of each isolate was determined by amplification with multiplex PCR of a partial sequence from the corresponding idiomorph. Overall, 43% out of the assessed isolates were MAT1-1 and 57 % were MAT1-2. Both mating types were identified within the 3 sampled regions Gharb, Saïs and Chaouia, but not in Tadla, where only MAT1-2 isolates were found. The presence of the two mating types highlighted here offers a suitable genetic condition for M. graminicola to occur sexual reproduction in Morocco. The potential of sexual recombination will be examined by the study of mating type frequencies using a large sample size as well as by searching and quantification of pseudothecia in the field. PMID:21534472

Elbekali, A Y; Ramdani, A; Tisserant, B; Deweer, C; Siah, A; Reignault, Ph; Halama, P

2010-01-01

163

Both mating types of the wheat pathogen Mycosphaerella graminicola are present in Morocco.  

UK PubMed Central (United Kingdom)

Septoria tritici blotch caused by the heterothallic ascomycete Mycosphaerella graminicola is one of the most currently damaging diseases on wheat crops worldwide. So far, no information was reported about the status of sexual reproduction of this pathogen under Moroccan conditions. We investigated here for the first time the occurrence of the two mating types (MAT1-1 and MAT1-2) of M. graminicola in Morocco by sampling 141 single-conidial isolates from 4 important wheat producing regions (Gharb, Saïs, Chaouia and Tadla). The mating type of each isolate was determined by amplification with multiplex PCR of a partial sequence from the corresponding idiomorph. Overall, 43% out of the assessed isolates were MAT1-1 and 57 % were MAT1-2. Both mating types were identified within the 3 sampled regions Gharb, Saïs and Chaouia, but not in Tadla, where only MAT1-2 isolates were found. The presence of the two mating types highlighted here offers a suitable genetic condition for M. graminicola to occur sexual reproduction in Morocco. The potential of sexual recombination will be examined by the study of mating type frequencies using a large sample size as well as by searching and quantification of pseudothecia in the field.

Elbekali AY; Ramdani A; Tisserant B; Deweer C; Siah A; Reignault P; Halama P

2010-01-01

164

Cell fusion assays for yeast mating pairs.  

Science.gov (United States)

Yeast mating provides an accessible genetic system for the discovery of fundamental mechanisms in eukaryotic cell fusion. Although aspects of yeast mating related to pheromone signaling and polarized growth have been intensively investigated, fusion itself is poorly understood. This chapter describes methods for measuring the overall efficiency of yeast cell fusion and for monitoring various stages of the fusion process including cell wall remodeling, plasma membrane fusion, and nuclear fusion. PMID:18979244

Grote, Eric

2008-01-01

165

Assortative mating for relative weight: genetic implications.  

UK PubMed Central (United Kingdom)

Most work on the genetics of relative weight has not considered the role of assortative mating, i.e., mate selection based on similarity between mates. We investigated the extent to which engaged men and women in an archival longitudinal database were similar to each other in relative body weight prior to marriage and cohabitation. After controlling for age, a small but statistically significant mate correlation was found for relative weight (r=.13, p=.023), indicating some assortative mating. Furthermore, we examined whether mate similarity in relative weight prior to marriage predicts survival of the marriage. No significant effects were found. In sum, these results are consistent with those of other studies in suggesting that there is a small but significant intermate correlation for relative weight. However, they are unique in showing that these results cannot be explained on the basis of (a) cohabitation, (b) age similarity, or (c) selective survival of marriages between couples more similar in relative weight. The implications of these findings for heritability studies, linkage studies, and the estimation of shared environmental effects are discussed.

Allison DB; Neale MC; Kezis MI; Alfonso VC; Heshka S; Heymsfield SB

1996-03-01

166

Effect of 60CO radiation processing in mate (Ilex paraguariensis)  

International Nuclear Information System (INIS)

[en] The mate (Ilex paraguariensis), a native species from South America, is mainly consumed as typical beverage called chimarrao and terere. An important problem that has been afflicting this product since a long time is its natural fungal contamination responsible to affect its physical, health and nutritional qualities. In order to improve this product quality, radiation processing can be effective in reducing pathogens levels, with minimal nutritional and sensory changes. The aim of this study was to evaluate the effectiveness of gamma radiation from 60Co at doses 0, 3, 5, 7 and 10kGy in reducing fungal contamination in mate, as well as analyze its nutritional and sensory characteristics. The following methodologies were applied: analysis of yeast and mold, total phenolic compounds analysis, antioxidant analysis, quantification of phenolic compounds and xanthines by liquid chromatography and sensory analysis. Microbiological analysis showed a decreasing molds and yeasts growth with increasing radiation doses. Regardless of the radiation dose applied there were no decrease of total phenolic compounds in both infusions. Chimarrao samples irradiated with 7 and 10kGy showed a decrease in the DPPH radical-scavenger activity, nevertheless for terere samples, there were no significant difference. Chimarrao chromatographic profile did not show a variation on xanthines quantification, however a 10kGy radiation dose caused a change to phenolic compounds quantitative profile. Terere samples did not show any significant difference to any analyzed compounds. Sensory analysis did not exhibit a significant difference between irradiated and non irradiated chimarrao samples, as well as between irradiated and non irradiated terere samples. It could be concluded that gamma radiation processing of mate may be a feasible alternative to industry, since there was a reduction on fungal contamination, without changes in sensory qualities and with minimum alterations in quantitative and qualitative profile of bioactive compounds. (author)

2009-01-01

167

Effect of 60Co radiation processing in mate (Ilex paraguariensis)  

International Nuclear Information System (INIS)

[en] The mate (Ilex paraguariensis), a native species from South America, is mainly consumed as typical beverage called chimarrao and terere. An important problem that has been afflicting this product since a long time is its natural fungal contamination responsible to affect its physical, health and nutritional qualities. In order to improve this product quality, radiation processing can be effective in reducing pathogens levels, with minimal nutritional and sensory changes. The aim of this study was to evaluate the effectiveness of gamma radiation from 60Co at doses 0, 3, 5, 7 and 10 kGy in reducing fungal contamination in mate, as well as analyze its nutritional and sensory characteristics. The following methodologies were applied: analysis of yeast and mold, total phenolic compounds analysis, antioxidant analysis, quantification of phenolic compounds and xanthines by liquid chromatography and sensory analysis. Microbiological analysis showed a decreasing molds and yeasts growth with increasing radiation doses. Regardless of the radiation dose applied there were no decrease of total phenolic compounds in both infusions. Chimarrao samples irradiated with 7 and 10 kGy showed a decrease in the DPPH radical-scavenger activity, nevertheless for terere samples, there were no significant difference. Chimarrao chromatographic profile did not show a variation on xanthines quantification, however a 10 kGy radiation dose caused a change to phenolic compounds quantitative profile. Terere samples did not show any significant difference to any analyzed compounds. Sensory analysis did not exhibit a significant difference between irradiated and non irradiated chimarrao samples, as well as between irradiated and non irradiated terere samples. It could be concluded that gamma radiation processing of mate may be a feasible alternative to industry, since there was a reduction on fungal contamination, without changes in sensory qualities and with minimum alterations in quantitative and qualitative profile of bioactive compounds. (author)

2009-01-01

168

Genetically Engineered Transvestites Reveal Novel Mating Genes in Budding Yeast.  

UK PubMed Central (United Kingdom)

Haploid budding yeast has two mating types, defined by the alleles of the MAT locus, MATa and MAT?. Two haploid cells of opposite mating types mate by signaling to each other using reciprocal pheromones and receptors, polarizing and growing towards each other, and eventually fusing to form a single diploid cell. The pheromones and receptors are necessary and sufficient to define a mating type, but other mating type-specific proteins make mating more efficient. We examined the role of these proteins by genetically engineering "transvestite" cells that swap the pheromone, pheromone receptor, and pheromone processing factors of one mating type for another. These cells mate with each other, but their mating is inefficient. By characterizing their mating defects and examining their transcriptomes, we found Afb1 (a-factor barrier), a novel MAT?-specific protein that interferes with a-factor, the pheromone secreted by MATa cells. Strong pheromone secretion is essential for efficient mating, and the weak mating of transvestites can be improved by boosting their pheromone production. Synthetic biology can characterize the factors that control efficiency in biological processes. In yeast, selection for increased mating efficiency is likely to have continually boosted pheromone levels and the ability to discriminate between partners who make more and less pheromone. This discrimination comes at a cost: weak mating in situations where all potential partners make less pheromone.

Huberman LB; Murray AW

2013-10-01

169

Mate sampling and choosiness in the sand goby.  

UK PubMed Central (United Kingdom)

To date, mate choice studies have mostly focused on establishing which mates are chosen or how the choices are performed. Here, we combined these two approaches by empirically testing how latency to mate is affected by various search costs, variation in mate quality and female quality in the sand goby (Pomatoschistus minutus). Our results show that females adjust their mating behaviour according to the costs and benefits of the choice situation. Specifically, they mated sooner when access to males was delayed and when the presence of other females presented a mate sampling cost. We also found a positive link between size variation among potential mating partners and spawning delay in some (but not all) experimental conditions. By contrast, we did not find the number of available males or the females' own body size ('quality') to affect mating latency. Finally, female mating behaviour varied significantly between years. These findings are notable for demonstrating that (i) mate sampling time is particularly sensitive to costs and, to a lesser degree, to variation among mate candidates, (ii) females' mating behaviour is sensitive to qualitative rather than to quantitative variation in their environment, and (iii) a snapshot view may describe mate sampling behaviour unreliably.

Lindström K; Lehtonen TK

2013-08-01

170

Floral longevity and autonomous selfing are altered by pollination and water availability in Collinsia heterophylla.  

UK PubMed Central (United Kingdom)

BACKGROUND AND AIMS: A plant investing in reproduction partitions resources between flowering and seed production. Under resource limitation, altered allocations may result in floral trait variations, leading to compromised fecundity. Floral longevity and timing of selfing are often the traits most likely to be affected. The duration of corolla retention determines whether fecundity results from outcrossing or by delayed selfing-mediated reproductive assurance. In this study, the role of pollination schedules and soil water availability on floral longevity and seed production is tested in Collinsia heterophylla (Plantaginaceae). METHODS: Using three different watering regimes and pollination schedules, effects on floral longevity and seed production were studied in this protandrous, flowering annual. KEY RESULTS: The results reveal that soil water status and pollination together influence floral longevity with low soil water and hand-pollinations early in the floral lifespan reducing longevity. However, early pollinations under excess water did not extend longevity, implying that resource surplus does not lengthen the outcrossing period. The results also indicate that pollen receipt, a reliable cue for fecundity, accelerates flower drop. Early corolla abscission under drought stress could potentially exacerbate sexual conflict in this protandrous, hermaphroditic species by ensuring self-pollen paternity and enabling male control of floral longevity. While pollination schedules did not affect fecundity, water stress reduced per-capita seed numbers. Unmanipulated flowers underwent delayed autonomous selfing, producing very few seeds, suggesting that inbreeding depression may limit benefits of selfing. CONCLUSIONS: In plants where herkogamy and dichogamy facilitate outcrossing, floral longevity determines reproductive success and mating system. Reduction in longevity under drought suggests a strong environmental effect that could potentially alter the preferred breeding mode in this mixed-mated species. Extrapolating the findings to unpredictable global drought cycles, it is suggested that in addition to reducing yield, water stress may influence the evolutionary trajectory of plant mating system.

Jorgensen R; Arathi HS

2013-09-01

171

HER2 and EGFR gene copy number alterations are predominant in high-grade salivary mucoepidermoid carcinoma irrespective of MAML2 fusion status.  

UK PubMed Central (United Kingdom)

AIMS: In this study, we aimed to investigate the molecular mechanisms underlying the development of mucoepidermoid carcinoma (MEC). METHODS AND RESULTS: In 31 cases, we examined the MAML2 fusion status using reverse transcriptase-polymerase chain reaction, and HER2 and EGFR status using immunohistochemistry and chromogenic in-situ hybridization. MAML2 fusions were detected in 15 (57.7%) of 26 MECs analysed, including 11 of 16 (68.8%) low-grade, two of four (50%) intermediate-grade and two of six (33.3%) high-grade MECs. HER2 gene amplification and an increased EGFR gene copy number (with balanced chromosome 7 high-polysomy) were each detected in four of 28 (14.3%) MECs analysed. Irrespective of MAML2 fusion status, all seven high-grade MECs had an increased gene copy number of either HER2 or EGFR, in a mutually exclusive manner, whereas such abnormalities were extremely rare in low- and intermediate-grade MEC. CONCLUSIONS: These results suggest that HER2 or EGFR gene abnormality could play an important role in the development of high-grade MEC, and also in the progression from MAML2 fusion-positive low-/intermediate-grade to high-grade in a subset of MEC. Furthermore, we suggest that high-grade MEC comprises a heterogeneous group of tumours in terms of molecular pathogenesis, in particular MAML2 fusion status.

Nakano T; Yamamoto H; Hashimoto K; Tamiya S; Shiratsuchi H; Nakashima T; Nishiyama K; Higaki Y; Komune S; Oda Y

2013-09-01

172

Burn-induced oxidative stress is altered by a low zinc status: kinetic study in burned rats fed a low zinc diet.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

As an initial subdeficient status of zinc, considered as an essential antioxidant trace element, is frequent in burned patients, we aim to assess the effects of low zinc dietary intakes on burn-induced oxidative stress, in an animal model. After 8 weeks of conditioning diets containing 80 ppm (contr...

Claeyssen, Richard; Andriollo-Sanchez, Maud; Arnaud, Josiane; Touvard, Laurence; Alonso, Antonia; Chancerelle, Yves

173

Alterations in the telomere length distribution and the subtelomeric methylation status in human vascular endothelial cells under elevated temperature in culture condition.  

UK PubMed Central (United Kingdom)

Temperature-associated alteration in the telomere lengths of vascular endothelial cells has not been well investigated. Telomere length of human umbilical vein endothelial cells (HUVECs) cultured at a high temperature (42 °C) was analyzed. Here described are heat-associated phenotypical alterations of human vascular endothelial cell under prolonged heat stress in terms of telomere length, telomerase activity, and the expression of telomere associated proteins and heat shock proteins. The genomic DNA extracted from HUVECs cultured for 3 days under 42 °C was digested with methylation-sensitive and -insensitive isoschizomers and was subjected to genomic Southern blot probed with a telomere DNA fragment. Their telomere lengths and telomere length distributions were analyzed. Telomerase activity and the expressions of telomere-associated RNA, telomere-associated proteins (TERC, TERT, TRF1, and TRF2), and heat shock proteins (Hsp60, Hsp70, and Hsp90) were also analyzed. At 42 °C, cell growth was suppressed and the cell senescence rate was transiently elevated. A proportional decrease in the number of long telomeres was observed transiently at 42 °C. A trend of subtelomeric hypomethylation and lowered telomerase activity were observed at 42 °C after 3-day culture. The altered phenotypes on day 1 seemed reactive responses for cell protection to heat, and those on day 3 seemed exhausted reactions after 3-day culture. Maintained expression was observed in Hsps, TRF2, and TERC. These altered phenotypes might contribute to cell-survival under prolonged heat stress.

Maeda T; Guan JZ; Koyanagi M; Makino N

2013-06-01

174

Studies on mating competition of irradiated melon flies  

International Nuclear Information System (INIS)

Mating competition is the key factor for fruit flies control by using sterile insect technique project. Mass rearing and irradiation can reduce the mating competition of fruit flies. This experiment has purpose to evaluate the mating competition of the irradiated melon fly. The results show that mating competition values of irradiated melon flies were 0.36 and 0.24 when they mated with normal and irradiated females. Both normal male and female can mate more frequency than irradiated flies. (Z=1.322, P

1994-01-01

175

A deficit in zinc availability can cause alterations in tubulin thiol redox status in cultured neurons and in the developing fetal rat brain.  

Science.gov (United States)

Zinc (Zn) deficiency during early development can result in multiple brain abnormalities and altered neuronal functions. In rats, a gestational deficit of Zn can affect the fetal brain cytoskeleton and signaling cascades involved in cellular processes that are central to brain development. In this paper, we tested the hypothesis that oxidative stress is involved in Zn deficiency-induced altered tubulin dynamics and the associated dysregulation of transcription factor NF-?B. For this purpose, we used two cell culture models (rat cortical neurons, human IMR-32 neuroblastoma cells) and an animal model of Zn deficiency. A low rate of in vitro tubulin polymerization, an increase in tubulin oligomers, and a higher protein cysteine oxidation were observed in the Zn-deficient neuronal cells and in gestation day 19 fetal brains obtained from dams fed marginal-Zn diets throughout pregnancy. These alterations could be prevented by treating the Zn-deficient cells with the reducing agent tris(2-carboxyethyl)phosphine or by the presence of N-acetylcysteine (NAC) and ?-lipoic acid (LA). Consistent with the above, Zn deficiency-induced tubulin-mediated alterations in transcription factor NF-?B nuclear translocation were prevented by treating IMR-32 cells with LA and NAC. Binding of the NF-?B protein p50, dynein, and karyopherin ? (components of the NF-?B transport complex) to ?-tubulin as well as the expression of NF-?B-dependent genes (Bcl-2, cyclin D1, and c-myc) was also restored by the addition of LA and NAC to Zn-deficient cells. In conclusion, a deficit in Zn viability could affect early brain development through: (1) an induction of oxidative stress, (2) tubulin oxidation, (3) altered tubulin dynamics, and (4) deregulation of signals (e.g., NF-?B) involved in critical developmental events. PMID:21600978

Mackenzie, Gerardo G; Salvador, Gabriela A; Romero, Carolina; Keen, Carl L; Oteiza, Patricia I

2011-04-30

176

A deficit in zinc availability can cause alterations in tubulin thiol redox status in cultured neurons and in the developing fetal rat brain.  

UK PubMed Central (United Kingdom)

Zinc (Zn) deficiency during early development can result in multiple brain abnormalities and altered neuronal functions. In rats, a gestational deficit of Zn can affect the fetal brain cytoskeleton and signaling cascades involved in cellular processes that are central to brain development. In this paper, we tested the hypothesis that oxidative stress is involved in Zn deficiency-induced altered tubulin dynamics and the associated dysregulation of transcription factor NF-?B. For this purpose, we used two cell culture models (rat cortical neurons, human IMR-32 neuroblastoma cells) and an animal model of Zn deficiency. A low rate of in vitro tubulin polymerization, an increase in tubulin oligomers, and a higher protein cysteine oxidation were observed in the Zn-deficient neuronal cells and in gestation day 19 fetal brains obtained from dams fed marginal-Zn diets throughout pregnancy. These alterations could be prevented by treating the Zn-deficient cells with the reducing agent tris(2-carboxyethyl)phosphine or by the presence of N-acetylcysteine (NAC) and ?-lipoic acid (LA). Consistent with the above, Zn deficiency-induced tubulin-mediated alterations in transcription factor NF-?B nuclear translocation were prevented by treating IMR-32 cells with LA and NAC. Binding of the NF-?B protein p50, dynein, and karyopherin ? (components of the NF-?B transport complex) to ?-tubulin as well as the expression of NF-?B-dependent genes (Bcl-2, cyclin D1, and c-myc) was also restored by the addition of LA and NAC to Zn-deficient cells. In conclusion, a deficit in Zn viability could affect early brain development through: (1) an induction of oxidative stress, (2) tubulin oxidation, (3) altered tubulin dynamics, and (4) deregulation of signals (e.g., NF-?B) involved in critical developmental events.

Mackenzie GG; Salvador GA; Romero C; Keen CL; Oteiza PI

2011-07-01

177

Transcriptome and functional analysis of mating in the basidiomycete Schizophyllum commune.  

UK PubMed Central (United Kingdom)

In this study, we undertook a functional characterization and transcriptome analysis that enabled a comprehensive study of the mating type loci of the mushroom Schizophyllum commune. Induced expression of both the bar2 receptor and the bap2(2) pheromone gene within 6 to 12 h after mates' contact was demonstrated by quantitative real-time PCR. Similar temporal expression patterns were confirmed for the allelic bbr1 receptor and bbp1 pheromone-encoding genes by Northern hybridization. Interestingly, the fusion of clamp connections to the subterminal cell was delayed in mating interactions in which one of the compatible partners expressed the bar2 receptor with a truncated C terminus. This developmental delay allowed the visualization of a green fluorescent protein (Gfp)-labeled truncated receptor at the cell periphery, consistent with a localization in the plasma membrane of unfused pseudoclamps. This finding does not support hypotheses envisioning a receptor localization to the nuclear membrane facilitating recognition between the two different nuclei present in each dikaryotic cell. Rather, Gfp fluorescence observed in such pseudoclamps indicated a role of receptor-pheromone interaction in clamp fusion. Transcriptome changes associated with mating interactions were analyzed in order to identify a role for pheromone-receptor interactions. We detected a total of 89 genes that were transcriptionally regulated in a mating type locus A-dependent manner, employing a cutoff of 5-fold changes in transcript abundance. Upregulation in cell cycle-related genes and downregulation of genes involved in metabolism were seen with this set of experiments. In contrast, mating type locus B-dependent transcriptome changes were observed in 208 genes, with a specific impact on genes related to cell wall and membrane metabolism, stress response, and the redox status of the cell.

Erdmann S; Freihorst D; Raudaskoski M; Schmidt-Heck W; Jung EM; Senftleben D; Kothe E

2012-05-01

178

Initial clinical experience with the HeartMate II axial-flow left ventricular assist device.  

UK PubMed Central (United Kingdom)

The redesigned HeartMate II, an axial-flow left ventricular assist device, is simpler, smaller, and easier to operate than are pulsatile pumps. These design characteristics should make the HeartMate II more reliable and durable and broaden the eligible population base. We implanted the HeartMate II in 43 patients (average age, 42 yr). The indication for use was bridge-to-heart transplantation in 26 patients and destination therapy in 17. The average duration of device support was 258 days (range, 1-761 days), and cumulative duration, more than 31 patient-years. Hemodynamic function improved in all patients during support. By 48 hours after implantation, the mean cardiac index had increased from 1.9+/-0.27 L/(min.m(2)) (baseline) to 3.5+/-0.8 L/(min.m(2)), and the pulmonary capillary wedge pressure had decreased from 24.8+/-11 mmHg to 18.5+/-5.3 mmHg. Of the 43 patients, 35 were discharged from the hospital. Support is ongoing in 27 patients (longest duration, >700 days). Nine patients died during support. Four patients had sufficient heart recovery to undergo pump explantation. Three patients underwent transplantation. One patient underwent device replacement after the pump driveline was fractured in a skateboarding accident; the device was removed in another patient because of a pump-pocket infection after 749 days of support. Of the 10 patients in whom the HeartMate II replaced a failed HeartMate I, 8 were discharged from the hospital. We have seen excellent results with use of the HeartMate II. Functional status and quality of life have greatly improved in patients who survived the perioperative period.

Frazier OH; Gemmato C; Myers TJ; Gregoric ID; Radovancevic B; Loyalka P; Kar B

2007-01-01

179

Initial clinical experience with the HeartMate II axial-flow left ventricular assist device.  

Science.gov (United States)

The redesigned HeartMate II, an axial-flow left ventricular assist device, is simpler, smaller, and easier to operate than are pulsatile pumps. These design characteristics should make the HeartMate II more reliable and durable and broaden the eligible population base. We implanted the HeartMate II in 43 patients (average age, 42 yr). The indication for use was bridge-to-heart transplantation in 26 patients and destination therapy in 17. The average duration of device support was 258 days (range, 1-761 days), and cumulative duration, more than 31 patient-years. Hemodynamic function improved in all patients during support. By 48 hours after implantation, the mean cardiac index had increased from 1.9+/-0.27 L/(min.m(2)) (baseline) to 3.5+/-0.8 L/(min.m(2)), and the pulmonary capillary wedge pressure had decreased from 24.8+/-11 mmHg to 18.5+/-5.3 mmHg. Of the 43 patients, 35 were discharged from the hospital. Support is ongoing in 27 patients (longest duration, >700 days). Nine patients died during support. Four patients had sufficient heart recovery to undergo pump explantation. Three patients underwent transplantation. One patient underwent device replacement after the pump driveline was fractured in a skateboarding accident; the device was removed in another patient because of a pump-pocket infection after 749 days of support. Of the 10 patients in whom the HeartMate II replaced a failed HeartMate I, 8 were discharged from the hospital. We have seen excellent results with use of the HeartMate II. Functional status and quality of life have greatly improved in patients who survived the perioperative period. PMID:17948075

Frazier, O H; Gemmato, Courtney; Myers, Timothy J; Gregoric, Igor D; Radovancevic, Brano; Loyalka, Pranav; Kar, Biswajit

2007-01-01

180

Realization of the chess mate solver application  

Directory of Open Access Journals (Sweden)

Full Text Available This paper presents details of the chess mate solver application, which is a part of the author’s Geniss general chess application. The problem chess is an important domain connected with solving of the chess problems. The Geniss Mate Solver (G.M.S.) application solves Mate-in-N-move problems. Main techniques used for the implementation of the application are full-width searching with Alpha-Beta pruning technique and zero evaluation function. The application is written in Delphi for Windows programming environment and the searching engine is completely coded in assembly language (about 10000 lines). This hybrid software structure enables efficient program development by using high-level programming environment and the realization of a very fast searching engine at the same time. The machine code is manually coded and could achieve above 7 million generated positions per second on the 1Ghz Celeron PC.

Vu?kovi? Vladan V.

2004-01-01

 
 
 
 
181

Schizotypy, creativity and mating success in humans  

Science.gov (United States)

There is an evolutionary puzzle surrounding the persistence of schizophrenia, since it is substantially heritable and associated with sharply reduced fitness. However, some of the personality traits which are predictive of schizophrenia are also associated with artistic creativity. Geoffrey Miller has proposed that artistic creativity functions to attract mates. Here, we investigate the relationship between schizotypal personality traits, creative activity, and mating success in a large sample of British poets, visual artists, and other adults. We show that two components of schizotypy are positively correlated with mating success. For one component, this relationship is mediated by creative activity. Results are discussed in terms of the evolution of human creativity and the genesis of schizophrenia.

Nettle, Daniel; Clegg, Helen

2005-01-01

182

Basidiomycete mating type genes and pheromone signaling.  

UK PubMed Central (United Kingdom)

The genome sequences of the basidiomycete Agaricomycetes species Coprinopsis cinerea, Laccaria bicolor, Schizophyllum commune, Phanerochaete chrysosporium, and Postia placenta, as well as of Cryptococcus neoformans and Ustilago maydis, are now publicly available. Out of these fungi, C. cinerea, S. commune, and U. maydis, together with the budding yeast Saccharomyces cerevisiae, have been investigated for years genetically and molecularly for signaling in sexual reproduction. The comparison of the structure and organization of mating type genes in fungal genomes reveals an amazing conservation of genes regulating the sexual reproduction throughout the fungal kingdom. In agaricomycetes, two mating type loci, A, coding for homeodomain type transcription factors, and B, encoding a pheromone/receptor system, regulate the four typical mating interactions of tetrapolar species. Evidence for both A and B mating type genes can also be identified in basidiomycetes with bipolar systems, where only two mating interactions are seen. In some of these fungi, the B locus has lost its self/nonself discrimination ability and thus its specificity while retaining the other regulatory functions in development. In silico analyses now also permit the identification of putative components of the pheromone-dependent signaling pathways. Induction of these signaling cascades leads to development of dikaryotic mycelia, fruiting body formation, and meiotic spore production. In pheromone-dependent signaling, the role of heterotrimeric G proteins, components of a mitogen-activated protein kinase (MAPK) cascade, and cyclic AMP-dependent pathways can now be defined. Additionally, the pheromone-dependent signaling through monomeric, small GTPases potentially involved in creating the polarized cytoskeleton for reciprocal nuclear exchange and migration during mating is predicted.

Raudaskoski M; Kothe E

2010-06-01

183

Sexual behavior, cannibalism, and mating plugs as sticky traps in the orb weaver spider Leucauge argyra (Tetragnathidae)  

Science.gov (United States)

Unpublished field observations in Leucauge argyra, a tropical orb weaver spider, suggest the occurrence of conspicuous mating plugs that could reduce or prevent remating attempts. Otherwise, the sexual behavior of this species remains unknown. The aims of this study were to describe the courtship behavior and copulation in L. argyra and investigate mating plug formation in this species. Fourteen virgin females and 12 plugged females were exposed to up to three males and checked for mating plug formation. Of the 12 virgins that copulated, nine produced plugs (five immediately after copulation), and the five plugged females that copulated produced another mating plug immediately after copulation. We did not detect the transfer of any male substance during copulation but observed a whitish liquid emerging from female genital ducts. Plug formation was positively associated with male twanging during courtship. One virgin and four plugged females cannibalized males. In seven trials with virgins and in three trials with plugged females, the male's palp adhered to a substance that emerged from female genital ducts and spread on her genital plate. The male had to struggle energetically to free his glued palp; two of these males were cannibalized while trying to release their palps. Females seem to determine copulation duration by altering the timing of mating plug formation and through sexual cannibalism. This is the first case reported of a mating plug as a sticky trap for males.

Aisenberg, Anita; Barrantes, Gilbert

2011-07-01

184

Desmin aggregate formation by R120G alphaB-crystallin is caused by altered filament interactions and is dependent upon network status in cells.  

UK PubMed Central (United Kingdom)

The R120G mutation in alphaB-crystallin causes desmin-related myopathy. There have been a number of mechanisms proposed to explain the disease process, from altered protein processing to loss of chaperone function. Here, we show that the mutation alters the in vitro binding characteristics of alphaB-crystallin for desmin filaments. The apparent dissociation constant of R120G alphaB-crystallin was decreased while the binding capacity was increased significantly and as a result, desmin filaments aggregated. These data suggest that the characteristic desmin aggregates seen as part of the disease histopathology can be caused by a direct, but altered interaction of R120G alphaB-crystallin with desmin filaments. Transfection studies show that desmin networks in different cell backgrounds are not equally affected. Desmin networks are most vulnerable when they are being made de novo and not when they are already established. Our data also clearly demonstrate the beneficial role of wild-type alphaB-crystallin in the formation of desmin filament networks. Collectively, our data suggest that R120G alphaB-crystallin directly promotes desmin filament aggregation, although this gain of a function can be repressed by some cell situations. Such circumstances in muscle could explain the late onset characteristic of the myopathies caused by mutations in alphaB-crystallin.

Perng MD; Wen SF; van den IJssel P; Prescott AR; Quinlan RA

2004-05-01

185

Desmin Aggregate Formation by R120G ?B-Crystallin Is Caused by Altered Filament Interactions and Is Dependent upon Network Status in Cells  

Science.gov (United States)

The R120G mutation in ?B-crystallin causes desmin-related myopathy. There have been a number of mechanisms proposed to explain the disease process, from altered protein processing to loss of chaperone function. Here, we show that the mutation alters the in vitro binding characteristics of ?B-crystallin for desmin filaments. The apparent dissociation constant of R120G ?B-crystallin was decreased while the binding capacity was increased significantly and as a result, desmin filaments aggregated. These data suggest that the characteristic desmin aggregates seen as part of the disease histopathology can be caused by a direct, but altered interaction of R120G ?B-crystallin with desmin filaments. Transfection studies show that desmin networks in different cell backgrounds are not equally affected. Desmin networks are most vulnerable when they are being made de novo and not when they are already established. Our data also clearly demonstrate the beneficial role of wild-type ?B-crystallin in the formation of desmin filament networks. Collectively, our data suggest that R120G ?B-crystallin directly promotes desmin filament aggregation, although this gain of a function can be repressed by some cell situations. Such circumstances in muscle could explain the late onset characteristic of the myopathies caused by mutations in ?B-crystallin.

Der Perng, Ming; Wen, Shu Fang; van den IJssel, Paul; Prescott, Alan R.; Quinlan, Roy A.

2004-01-01

186

Desmin aggregate formation by R120G alphaB-crystallin is caused by altered filament interactions and is dependent upon network status in cells.  

Science.gov (United States)

The R120G mutation in alphaB-crystallin causes desmin-related myopathy. There have been a number of mechanisms proposed to explain the disease process, from altered protein processing to loss of chaperone function. Here, we show that the mutation alters the in vitro binding characteristics of alphaB-crystallin for desmin filaments. The apparent dissociation constant of R120G alphaB-crystallin was decreased while the binding capacity was increased significantly and as a result, desmin filaments aggregated. These data suggest that the characteristic desmin aggregates seen as part of the disease histopathology can be caused by a direct, but altered interaction of R120G alphaB-crystallin with desmin filaments. Transfection studies show that desmin networks in different cell backgrounds are not equally affected. Desmin networks are most vulnerable when they are being made de novo and not when they are already established. Our data also clearly demonstrate the beneficial role of wild-type alphaB-crystallin in the formation of desmin filament networks. Collectively, our data suggest that R120G alphaB-crystallin directly promotes desmin filament aggregation, although this gain of a function can be repressed by some cell situations. Such circumstances in muscle could explain the late onset characteristic of the myopathies caused by mutations in alphaB-crystallin. PMID:15004226

Perng, Ming Der; Wen, Shu Fang; van den IJssel, Paul; Prescott, Alan R; Quinlan, Roy A

2004-03-05

187

Heterozygosity-based assortative mating in blue tits (Cyanistes caeruleus): implications for the evolution of mate choice.  

UK PubMed Central (United Kingdom)

The general hypothesis of mate choice based on non-additive genetic traits suggests that individuals would gain important benefits by choosing genetically dissimilar mates (compatible mate hypothesis) and/or more heterozygous mates (heterozygous mate hypothesis). In this study, we test these hypotheses in a socially monogamous bird, the blue tit (Cyanistes caeruleus). We found no evidence for a relatedness-based mating pattern, but heterozygosity was positively correlated between social mates, suggesting that blue tits may base their mating preferences on partner's heterozygosity. We found evidence that the observed heterozygosity-based assortative mating could be maintained by both direct and indirect benefits. Heterozygosity reflected individual quality in both sexes: egg production and quality increased with female heterozygosity while more heterozygous males showed higher feeding rates during the brood-rearing period. Further, estimated offspring heterozygosity correlated with both paternal and maternal heterozygosity, suggesting that mating with heterozygous individuals can increase offspring genetic quality. Finally, plumage crown coloration was associated with male heterozygosity, and this could explain unanimous mate preferences for highly heterozygous and more ornamented individuals. Overall, this study suggests that non-additive genetic traits may play an important role in the evolution of mating preferences and offers empirical support to the resolution of the lek paradox from the perspective of the heterozygous mate hypothesis.

García-Navas V; Ortego J; Sanz JJ

2009-08-01

188

The mating-type-related bias of gene conversion in Schizosaccharomyces pombe.  

Science.gov (United States)

The mating-type bias (mat-bias) of gene conversion was previously described as a phenomenon in which the number of prototrophic recombinants in an ura4A heteroallelic two-factor cross relates to the mating types of the parents. We show now that the mat-bias is restricted neither to ura4A nor to recombination hotspots, but occurs at other genomic loci, too. It is specific for gene conversion and absent in azygotic meiosis. Thus, the mat-bias must originate from mating-type-specific "imprinting" events before karyogamy takes place. Structural variations of the mating-type locus, such as h(+N), h(+S), h(-S), h(+smtDelta), or h(-smtDelta), showed mat-bias manifestation. Mutations in genes coding for histone acetylase (gcn5, ada2) and histone deacetylase (hos2, clr6) activities smooth or abolish the mat-bias. In addition, the mat-bias depends on the presence of Swi5. We propose a new role for Swi5 and the histone acetylation status in mat-bias establishment through directionality of repair from the intact chromatid to the broken chromatid. PMID:18845847

Parvanov, Emil; Kohli, Juerg; Ludin, Katja

2008-10-09

189

Evolution of mating pheromone and receptor genes in Pucciniomycotina  

Science.gov (United States)

Mating pheromones and their receptors act as a switch controlling phenotypic changes required for successful mating in fungi. Although basidiomycete mating pheromones and their processing were first described in Rhodosporidium toruloides a “red yeast” in the Sporidiobolales, the receptor gene was ne...

190

Sensory regulation of C. elegans male mate-searching behavior.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

How do animals integrate internal drives and external environmental cues to coordinate behaviors? We address this question by studying mate-searching behavior in C. elegans. C. elegans males explore their environment in search of mates (hermaphrodites) and will leave food if mating partners are abse...

Barrios, A; Nurrish, S; Emmons, SW

191

Disruptive ecological selection on a mating cue.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Adaptation to divergent ecological niches can result in speciation. Traits subject to disruptive selection that also contribute to non-random mating will facilitate speciation with gene flow. Such 'magic' or 'multiple-effect' traits may be widespread and important for generating biodiversity, but st...

Merrill, RM; Wallbank, RW; Bull, V; Salazar, PC; Mallet, J; Stevens, M; Jiggins, CD

192

AA, mating of BST magnet halves  

CERN Document Server

The AA had 2 types of bending magnets: BLG (window-frame,long and narrow) and BST (H-type, short and wide). The BST had a steel length of 2.71 m, a "good field" width of 0.564 m, and a weight of about 75 t. Here we see the mating of two BST halves.

1980-01-01

193

MATE (Mentale Aspecten van Team Effectiviteit) (MATE (Mental Aspects of Team Effectiveness)).  

Science.gov (United States)

MATE is a model that gives insight in the stages of team development by integrating the views on team effectiveness from both the military organisation and organisational psychology. Based on this theoretical framework, a practical handout was developed t...

I. V. Beijl J. P. Meer M. H. Hart

2008-01-01

194

Mate switching as a function of mate quality in convict cichlids, Cichlasoma nigrofasciatum.  

UK PubMed Central (United Kingdom)

We examined mate switching between mated pairs of monogamous convict cichlids as a function of mate quality (size). A mated pair was established in each half of a 284-litre aquarium, an opaque partition separating the two pairs. When the partition was removed, mis-assorted pairs (large males with small females competing with small males with large females) re-sorted themselves such that the larger male and the larger female paired with each other 46% of the time. In contrast, when we exposed initially assorted pairs to each other, large pairs remained intact most of the time and dominated smaller pairs. The pair containing the large male, whether re-sorted or intact, dominated over the other pair and was the only one seen to spawn. Re-sortment resulted both from a preference of males for larger females and of females for larger males, and from the ability of larger individuals to displace their smaller consexual. Small females, however, when paired with a large male, often dominated large females and prevented the large female from mating with the large male. Re-sortment was also influenced by the compatibility of large individuals in their initial pairing situation. Large individuals that had been more compatible with their initial mates were less likely to switch mates. Our results support both the better-option and the incompatibility hypotheses of mate-switching. The availability of more than one breeding site in the aquarium had no effect on the frequency of re-sortment. Copyright 1998 The Association for the Study of Animal Behaviour. Copyright 1998 The Association for the Study of Animal Behaviour.

Itzkowitz M

1998-05-01

195

Cdc42 explores the cell periphery for mate selection in fission yeast.  

UK PubMed Central (United Kingdom)

How cells polarize in response to external cues is a fundamental biological problem. For mating, yeast cells orient growth toward the source of a pheromone gradient produced by cells of the opposite mating type. Polarized growth depends on the small GTPase Cdc42, a central eukaryotic polarity regulator that controls signaling, cytoskeleton polarization, and vesicle trafficking. However, the mechanisms of polarity establishment and mate selection in complex cellular environments are poorly understood. Here we show that, in fission yeast, low-level pheromone signaling promotes a novel polarization state, where active Cdc42, its GEF Scd1, and scaffold Scd2 form colocalizing dynamic zones that sample the periphery of the cell. Two direct Cdc42 effectors--actin cables marked by myosin V Myo52 and the exocyst complex labeled by Sec6 and Sec8--also dynamically colocalize with active Cdc42. However, these cells do not grow due to a block in the exocytosis of cell wall synthases Bgs1 and Bgs4. High-level pheromone stabilizes active Cdc42 zones and promotes cell wall synthase exocytosis and polarized growth. However, in the absence of prior low-level pheromone signaling, exploration fails, and cells polarize growth at cell poles by default. Consequently, these cells show altered partner choice, mating preferentially with sister rather than nonsister cells. Thus, Cdc42 exploration serves to orient growth for partner selection. This process may also promote genetic diversification.

Bendezú FO; Martin SG

2013-01-01

196

Mating choice of Ceratitis capitata (Wiedemann) (Diptera: Tephritidae): influence of male ageing on mating success  

International Nuclear Information System (INIS)

The objective of this study was to evaluate the effect of male ageing on male pheromone release and mating success of Ceratitis capitata (Wiedemann). The effects of male ageing on mating were evaluated on fi ve and 21 d-old males by assessing their mating success (males chosen by a female for copulation) and the amount of males releasing the sex pheromone. The mating success was evaluated by using several ratios of young to older males by increasing the number of older males:young males from 1:1 to 5:1. The mating success of the 1:1 ratio was also evaluated in fi eld cages. The evaluation of the mating success (in the 1:1 ratio) showed a clear preference of the females for young males. Sex pheromone emission was much more common on young than older males. Even in cases were older males were more abundant (ratios 2:1 and 3:1), females still chose the young males. However, females could not distinguish young from older males in ratios of 4:1 or 5:1. Our data indicate that the ageing of C. capitata males has a considerable negative effect on their reproductive success, especially if they are found in a proportion any lower than 3:1. (author)

2009-01-01

197

[Mating choice of Ceratitis capitata (Wiedemann) (Diptera: Tephritidae): influence of male ageing on mating success].  

UK PubMed Central (United Kingdom)

The objective of this study was to evaluate the effect of male ageing on male pheromone release and mating success of Ceratitis capitata (Wiedemann). The effects of male ageing on mating were evaluated on five and 21 d-old males by assessing their mating success (males chosen by a female for copulation) and the amount of males releasing the sex pheromone. The mating success was evaluated by using several ratios of young to older males by increasing the number of older males:young males from 1:1 to 5:1. The mating success of the 1:1 ratio was also evaluated in field cages. The evaluation of the mating success (in the 1:1 ratio) showed a clear preference of the females for young males. Sex pheromone emission was much more common on young than older males. Even in cases were older males were more abundant (ratios 2:1 and 3:1), females still chose the young males. However, females could not distinguish young from older males in ratios of 4:1 or 5:1. Our data indicate that the ageing of C. capitata males has a considerable negative effect on their reproductive success, especially if they are found in a proportion any lower than 3:1.

Silva Neto AM; Dias VS; Joachim-Bravo IS

2009-09-01

198

You can't always get what you want: size assortative mating by mutual mate choice as a resolution of sexual conflict  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Assortative mating patterns for mate quality traits like body size are often observed in nature. However, the underlying mechanisms that cause assortative mating patterns are less well known. Sexual selection is one important explanation for assortment, suggesting that i) one (usually the female) or both sexes could show preferences for mates of similar size or ii) mutual mate choice could resolve sexual conflict over quality traits into assortment. We tested these hypotheses experimentally in the socially monogamous cichlid fish Pelvicachromis taeniatus, in which mate choice is mutual. Results In mate choice experiments, both sexes preferred large mates irrespective of own body size suggesting mating preferences are not size-assortative. Especially males were highly selective for large females, probably because female body size signals direct fitness benefits. However, when potential mates were able to interact and assess each other mutually they showed size-assortative mating patterns, i.e. the likelihood to mate was higher in pairs with low size differences between mates. Conclusion Due to variation in body size, general preferences for large mating partners result in a sexual conflict: small, lower quality individuals who prefer themselves large partners are unacceptable for larger individuals. Relative size mismatches between mates translate into a lower likelihood to mate, suggesting that the threshold to accept mates depends on own body size. These results suggest that the underlying mechanism of assortment in P. taeniatus is mutual mate choice resolving the sexual conflict over mates, rather than preference for mates of similar size.

Baldauf Sebastian A; Kullmann Harald; Schroth Stefanie H; Thünken Timo; Bakker Theo CM

2009-01-01

199

Thyroid status alters gill ionic metabolism and chloride cell morphology as evidenced by scanning electron microscopy in a teleost Anabas testudineus (Bloch): short and long term in vivo study.  

Science.gov (United States)

Gill is the main organ of osmotic regulation in teleosts and chloride cells are the sites of ion transport across gill epithelium. Thyroid hormones are implicated in the regulation of osmotic balance in teleosts also. Treatment with 6-propyl thiouracil (6-PTU) inhibited the membrane bound enzyme Na+K+ ATPase in the gill while triiodothyronine (T3) injection stimulated it in a short-term in vivo study in the teleost Anabas testudineus. Na+, K+ and Ca2+ ions were also decreased in the 6-PTU treated fish and the T3 treatment increased their concentrations in the gill lamellae. The gill morphology also changed according to the thyroid status in the long term study. 6-PTU treatment altered the typical serrated morphology of the gill lamellae, while the T3 treatment reversed it. T3 injection increased the density of pavement and chloride cells as evidenced by scanning electron microscopy. The results demonstrate that physiological status of the thyroid influences gill Na+ pump activity and chloride cell morphological changes. Further, the study suggests a regulatory role of T3 on gill ions (Na+, K+ and Ca2+), Na+K+ and Ca2+ ATPase activity and the different gill cell types in A. testudineus. PMID:18254206

Sreejith, P; Beyo, R S; Prasad, G; Sunny, F; Oommen, O V

2007-12-01

200

Thyroid status alters gill ionic metabolism and chloride cell morphology as evidenced by scanning electron microscopy in a teleost Anabas testudineus (Bloch): short and long term in vivo study.  

UK PubMed Central (United Kingdom)

Gill is the main organ of osmotic regulation in teleosts and chloride cells are the sites of ion transport across gill epithelium. Thyroid hormones are implicated in the regulation of osmotic balance in teleosts also. Treatment with 6-propyl thiouracil (6-PTU) inhibited the membrane bound enzyme Na+K+ ATPase in the gill while triiodothyronine (T3) injection stimulated it in a short-term in vivo study in the teleost Anabas testudineus. Na+, K+ and Ca2+ ions were also decreased in the 6-PTU treated fish and the T3 treatment increased their concentrations in the gill lamellae. The gill morphology also changed according to the thyroid status in the long term study. 6-PTU treatment altered the typical serrated morphology of the gill lamellae, while the T3 treatment reversed it. T3 injection increased the density of pavement and chloride cells as evidenced by scanning electron microscopy. The results demonstrate that physiological status of the thyroid influences gill Na+ pump activity and chloride cell morphological changes. Further, the study suggests a regulatory role of T3 on gill ions (Na+, K+ and Ca2+), Na+K+ and Ca2+ ATPase activity and the different gill cell types in A. testudineus.

Sreejith P; Beyo RS; Prasad G; Sunny F; Oommen OV

2007-12-01

 
 
 
 
201

Variation in male mate choice in Drosophila melanogaster.  

UK PubMed Central (United Kingdom)

Male mate choice has been reported in the fruit fly, Drosophila melanogaster, even though males of this species were previously thought to maximise their fitness by mating with all available females. To understand the evolution of male mate choice it is important to understand variation in male mating preferences. Two studies, using different stock populations and different methods, have reported contrasting patterns of variation in male mate choice in D. melanogaster. Two possible explanations are that there are evolved differences in each stock population or that the methods used to measure choice could have biased the results. We investigated these hypotheses here by repeating the methods used in one study in which variable male mate choice was found, using the stock population from the other study in which choice was not variable. The results showed a significant resource-independent male preference for less fecund, smaller females, which contrasts with previous observations of male mate choice. This indicates that different selection pressures between populations have resulted in evolved differences in the expression of male mate choice. It also reveals phenotypic plasticity in male mate choice in response to cues encountered in each choice environment. The results highlight the importance of variation in male mate choice, and of identifying mechanisms in order to understand the evolution of mate choice under varying ecological conditions.

Edward DA; Chapman T

2013-01-01

202

Parental control over mate choice to prevent marriages with out-group members: a study among mestizos, Mixtecs, and Blacks in Mexico.  

Science.gov (United States)

The present research examined how a preference for influencing the mate choice of one's offspring is associated with opposition to out-group mating among parents from three ethnic groups in the Mexican state of Oaxaca: mestizos (people of mixed descent, n = 103), indigenous Mixtecs (n = 65), and blacks (n = 35). Nearly all of the men in this study were farmworkers or fishermen. Overall, the level of preferred parental influence on mate choice was higher than in Western populations, but lower than in Asian populations. Only among the Mixtecs were fathers more in favor of parental influence on the mate choice of children than mothers were. As predicted, opposition to out-group mating was an important predictor of preferred parental influence on mate choice, more so among fathers than among mothers, especially in the mestizo group-the group with the highest status. In addition, women, and especially mestizo women, expressed more opposition to out-group mating than men did. PMID:22875548

Buunk, Abraham P; Pollet, Thomas V; Dubbs, Shelli

2012-09-01

203

Osmotic balance regulates cell fusion during mating in Saccharomyces cerevisiae.  

UK PubMed Central (United Kingdom)

Successful zygote formation during yeast mating requires cell fusion of the two haploid mating partners. To ensure that cells do not lyse as they remodel their cell wall, the fusion event is both temporally and spatially regulated: the cell wall is degraded only after cell-cell contact and only in the region of cell-cell contact. To understand how cell fusion is regulated, we identified mutants defective in cell fusion based upon their defect in mating to a fus1 fus2 strain (Chenevert, J., N. Valtz, and I. Herskowitz. 1994. Genetics 136:1287-1297). Two of these cell fusion mutants are defective in the FPS1 gene, which codes for a glycerol facilitator (Luyten, K., J. Albertyn, W.F. Skibbe, B.A. Prior, J. Ramos, J.M. Thevelein, and S. Hohmann. 1995. EMBO [Eur. Mol. Biol. Organ.] J. 14:1360-1371). To determine whether inability to maintain osmotic balance accounts for the defect in cell fusion in these mutants, we analyzed the behavior of an fps1Delta mutant with reduced intracellular glycerol levels because of a defect in the glycerol-3-phosphate dehydrogenase (GPD1) gene (Albertyn, J., S. Hohmann, J.M. Thevelein, and B.A. Prior. 1994. Mol. Cell. Biol. 14:4135-4144): deletion of GPD1 partially suppressed the cell fusion defect of fps1 mutants. In contrast, overexpression of GPD1 exacerbated the defect. The fusion defect could also be partially suppressed by 1 M sorbitol. These observations indicate that the fusion defect of fps1 mutants results from inability to regulate osmotic balance and provide evidence that the osmotic state of the cell can regulate fusion. We have also observed that mutants expressing hyperactive protein kinase C exhibit a cell fusion defect similar to that of fps1 mutants. We propose that Pkc1p regulates cell fusion in response to osmotic disequilibrium. Unlike fps1 mutants, fus1 and fus2 mutants are not influenced by expression of GPD1 or by 1 M sorbitol. Their fusion defect is thus unlikely to result from altered osmotic balance.

Philips J; Herskowitz I

1997-09-01

204

Effects of age and mating on female sex attractant pheromone levels in the sorghum plant bug, Stenotus rubrovittatus (Matsumura).  

UK PubMed Central (United Kingdom)

Previous work has shown that male sorghum plant bugs, Stenotus rubrovittatus (Matsumura) (Heteroptera: Miridae), are more attracted to young virgin females than to old virgin females and are not attracted to mated females. Therefore, we examined the effects of age and mating status on female sex pheromone levels. The pheromone components, hexyl butyrate, (E)-hex-2-en-1-yl butyrate, and (E)-4-oxohex-2-enal, were collected from females in two different ways. First, the compounds were extracted from whole bodies of each female and quantified by gas chromatography-mass spectrometry (GC-MS). Pheromone levels extracted from virgin female bodies decreased with age. In females that had just mated, pheromone levels did not differ from those of virgin females, and pheromone levels in mated females remained relatively constant up to 15 d after mating. This absence of change in pheromone levels extracted from whole bodies of mated females is not congruent with previous reports of lack of male attraction to these females. In a second method for pheromone recovery (adsorption on a PDMS-coated stir bar), GC-MS analysis showed that mated females released lower amounts of pheromone components compared to those emitted by virgin females of the same age (4 d). As was the case with whole body extracts, young virgin females (3 d) released higher amounts of pheromone components than did old virgin females (8 d). The results suggest that male response in S. rubrovittatus is dictated more by the quantities of pheromone components released into the volatile headspace by females than by the quantities present in the body.

Oku K; Yasuda T

2010-05-01

205

Mate choice evolution, dominance effects, and the maintenance of genetic variation.  

UK PubMed Central (United Kingdom)

Female mate choice influences the maintenance of genetic variation by altering the mating success of males with different genotypes. The evolution of preferences themselves, on the other hand, depends on genetic variation present in the population. Few models have tracked this feedback between a choice gene and its effects on genetic variation, in particular when genes that determine offspring viability and attractiveness have dominance effects. Here we build a population genetic model that allows comparing the evolution of various choice rules in a single framework. We first consider preferences for good genes and show that focused preferences for homozygotes evolve more easily than broad preferences, which allow heterozygous males high mating success too. This occurs despite better maintenance of genetic diversity in the latter scenario, and we discuss why empirical findings of superior mating success of heterozygous males consequently do not immediately lead to a better understanding of the lek paradox. Our results thus suggest that the mechanisms that help maintain genetic diversity also have a flipside of making female choice an inaccurate means of producing the desired kind of offspring. We then consider preferences for heterozygosity per se, and show that these evolve only under very special conditions. Choice for compatible genotypes can evolve but its selective advantage diminishes quickly due to frequency-dependent selection. Finally, we show that our model reproduces earlier results on selfing, when the female choice strategy produces assortative mating. Overall, our model indicates that various forms of heterozygote-favouring (or variable) female choice pose a problem for the theory of sexual ornamentation based on indirect benefits, rather than a solution.

Lehmann L; Keller LF; Kokko H

2007-01-01

206

Optimizing mating schemes in fish breeding  

Directory of Open Access Journals (Sweden)

Full Text Available The optimal contribution selection method and the simulated annealing algorithm were used to maximize the genetic gain and reduce inbreeding in fish breeding populations. This study considered the following mating designs: full factorial (3 x 3); full factorial (6 x 6) and nested (6 males x 18 females). A quantitative trait based on a strictly additive and polygenic model was simulated. Two levels for the number of genotyped offspring (360 or 720) and three levels of heritability (0.1; 0.3; 0.5) were assumed. The best results in terms of DF and DG were obtained with the full factorial design (6 x 6) and considering a trait with a high heritability. The optimal family size was found at 20 fish per mating.

E. D'Agaro; J. A. Woolliams; C. S. Haley; D. Lanari

2010-01-01

207

Polycrystalline diamond cutting element with mating recess  

Energy Technology Data Exchange (ETDEWEB)

This patent describes a polycrystalline diamond cutting element with mating recess for use on a cutting tool. It comprises: a mounting body having a leading face and a trailing face and a relatively thin layer of super hard material carried on the leading face of the mounting body and defining a cutting face for the cutting element. Also described is a bit for use in drilling earthen formations.

Keith, C.W.

1990-03-27

208

Sport participation influences perceptions of mate characteristics.  

UK PubMed Central (United Kingdom)

Sport provides a context in which mate choice can be facilitated by the display of athletic prowess. Previous work has shown that, for females, team sport athletes are more desirable as mates than individual sport athletes and non-participants. In the present study, the perceptions of males and females were examined regarding potential mates based on sport participation. It was predicted that team sport athletes would be more positively perceived than individual sport athletes and non-participants by both males and females. A questionnaire, a photograph, and manipulated descriptions were used to gauge perceptual differences with respect to team sport athletes, individual sport athletes, and extra-curricular club participants for 125 females and 119 males from a Canadian university. Both team and individual sport athletes were perceived as being less lazy, more competitive, and healthier than non-participants by both males and females. Interestingly, females perceived male athletes as more promiscuous than non-athletes, which upholds predictions based on previous research indicating (a) athletes have more sexual partners than non-athletes, and (b) females find athletes more desirable as partners than non-participants. Surprisingly, only males perceived female team sport athletes as more dependable than non-participants, and both team and individual sport athletes as more ambitious. This raises questions regarding the initial hypothesis that male team athletes would be perceived positively by females because of qualities such as the ability to cooperate, likeability, and the acceptance of responsibilities necessary for group functioning. Future studies should examine similar questions with a larger sample size that encompasses multiple contexts, taking into account the role of the social profile of sport in relation to mate choice and perception.

Schulte-Hostedde AI; Eys MA; Emond M; Buzdon M

2012-01-01

209

Assortative mating and fragmentation within dog breeds  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background There are around 400 internationally recognized dog breeds in the world today, with a remarkable diversity in size, shape, color and behavior. Breeds are considered to be uniform groups with similar physical characteristics, shaped by selection rooted in human preferences. This has led to a large genetic difference between breeds and a large extent of linkage disequilibrium within breeds. These characteristics are important for association mapping of candidate genes for diseases and therefore make dogs ideal models for gene mapping of human disorders. However, genetic uniformity within breeds may not always be the case. We studied patterns of genetic diversity within 164 poodles and compared it to 133 dogs from eight other breeds. Results Our analyses revealed strong population structure within poodles, with differences among some poodle groups as pronounced as those among other well-recognized breeds. Pedigree analysis going three generations back in time confirmed that subgroups within poodles result from assortative mating imposed by breed standards as well as breeder preferences. Matings have not taken place at random or within traditionally identified size classes in poodles. Instead, a novel set of five poodle groups was identified, defined by combinations of size and color, which is not officially recognized by the kennel clubs. Patterns of genetic diversity in other breeds suggest that assortative mating leading to fragmentation may be a common feature within many dog breeds. Conclusion The genetic structure observed in poodles is the result of local mating patterns, implying that breed fragmentation may be different in different countries. Such pronounced structuring within dog breeds can increase the power of association mapping studies, but also represents a serious problem if ignored. In dog breeding, individuals are selected on the basis of morphology, behaviour, working or show purposes, as well as geographic population structure. The same processes which have historically created dog breeds are still ongoing, and create further subdivision within current dog breeds.

Björnerfeldt Susanne; Hailer Frank; Nord Maria; Vilà Carles

2008-01-01

210

Margarines fortified with ?-linolenic acid, eicosapentaenoic acid, or docosahexaenoic acid alter the fatty acid composition of erythrocytes but do not affect the antioxidant status of healthy adults.  

UK PubMed Central (United Kingdom)

We aimed to investigate the effects of increased intake of ?-linolenic acid (ALA), EPA, or DHA incorporated into a food matrix on the fatty acid composition of erythrocytes and on biomarkers of oxidant/antioxidant status. To this end, a controlled dietary study was conducted in 74 healthy men and women. The participants were randomly assigned to 1 of 3 interventions in which margarines fortified with either 10 weight percent ALA, EPA, or DHA ethyl esters replaced their normal spread for 6 wk. The total intakes of ALA, EPA, and DHA were 4.4, 2.2, and 2.3 g/d, respectively. Consuming EPA increased the erythrocyte proportion of EPA (394%) and the omega-3 index (sum of EPA and DHA, 38%). Consumption of DHA increased erythrocyte DHA (91%), the omega-3 index (98%), and EPA (137%). The omega-3 index increased to a significantly greater extent in the DHA group than in the EPA group. ALA did not increase erythrocyte EPA or the omega-3 index. We found no change in plasma uric acid or antioxidant capacity in any of the groups. Plasma malondialdehyde (MDA) increased with the EPA and DHA interventions. All 3 interventions decreased erythrocyte linoleic acid hydroperoxides but did not affect their MDA concentrations. In conclusion, the intake of both isolated EPA and DHA incorporated into margarine resulted in an enhanced incorporation of EPA and DHA into erythrocytes. Our findings indicate that DHA is quantitatively superior to EPA in view of the EPA+DHA tissue incorporation and also that 4 g/d ALA is not sufficient to increase the omega-3 index over a 6-wk period.

Egert S; Lindenmeier M; Harnack K; Krome K; Erbersdobler HF; Wahrburg U; Somoza V

2012-09-01

211

Fish oil and inflammatory status alter the n-3 to n-6 balance of the endocannabinoid and oxylipin metabolomes in mouse plasma and tissues.  

Science.gov (United States)

It is well established that dietary intake of n-3 fatty acids is associated with anti-inflammatory effects, and this has been linked to modulation of the oxylipin and endocannabinoid metabolomes. However, the amount of data on specific tissue effects is limited, and it is not known how inflammation affects this relation. In the present study we systematically explored the combined effects of n-3 fatty acid diets and inflammation on the in vivo endocannabinoid and oxylipin metabolomes using a multicompartment, detailed targeted lipidomics approach. Male C57BL/6 mice received diets containing 0, 1, or 3 % w/w fish oil (FO) for 6 weeks, after which 2 mg/kg LPS or saline was administered i.p. Levels of endocannabinoids/N-acylethanolamines (NAEs) and oxylipins, covering n-3 and n-6 fatty acid derived compounds, were determined in plasma, liver, ileum and adipose tissue using LC-MS/MS. FO generally increased 'n-3' NAEs and oxylipins at the expense of compounds derived from other fatty acids, affecting all branches of the oxylipin metabolome. LPS generally increased levels of endocannabinoids/NAEs and oxylipins, with opposing effects across plasma and tissues. Multivariate data analysis revealed that separation between diet groups in the saline treated groups was primarily explained by decreases in other than n-3 derived compounds. In the LPS treated groups, the separation was primarily explained by increases in n-3 derived compounds. In conclusion, FO caused marked changes in the n-3 to n-6 balance of the endocannabinoid and oxylipin metabolomes, with specific effects depending on inflammatory status. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s11306-012-0421-9) contains supplementary material, which is available to authorized users. PMID:23136559

Balvers, Michiel G J; Verhoeckx, Kitty C M; Bijlsma, Sabina; Rubingh, Carina M; Meijerink, Jocelijn; Wortelboer, Heleen M; Witkamp, Renger F

2012-04-11

212

Fish oil and inflammatory status alter the n-3 to n-6 balance of the endocannabinoid and oxylipin metabolomes in mouse plasma and tissues.  

UK PubMed Central (United Kingdom)

It is well established that dietary intake of n-3 fatty acids is associated with anti-inflammatory effects, and this has been linked to modulation of the oxylipin and endocannabinoid metabolomes. However, the amount of data on specific tissue effects is limited, and it is not known how inflammation affects this relation. In the present study we systematically explored the combined effects of n-3 fatty acid diets and inflammation on the in vivo endocannabinoid and oxylipin metabolomes using a multicompartment, detailed targeted lipidomics approach. Male C57BL/6 mice received diets containing 0, 1, or 3 % w/w fish oil (FO) for 6 weeks, after which 2 mg/kg LPS or saline was administered i.p. Levels of endocannabinoids/N-acylethanolamines (NAEs) and oxylipins, covering n-3 and n-6 fatty acid derived compounds, were determined in plasma, liver, ileum and adipose tissue using LC-MS/MS. FO generally increased 'n-3' NAEs and oxylipins at the expense of compounds derived from other fatty acids, affecting all branches of the oxylipin metabolome. LPS generally increased levels of endocannabinoids/NAEs and oxylipins, with opposing effects across plasma and tissues. Multivariate data analysis revealed that separation between diet groups in the saline treated groups was primarily explained by decreases in other than n-3 derived compounds. In the LPS treated groups, the separation was primarily explained by increases in n-3 derived compounds. In conclusion, FO caused marked changes in the n-3 to n-6 balance of the endocannabinoid and oxylipin metabolomes, with specific effects depending on inflammatory status. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s11306-012-0421-9) contains supplementary material, which is available to authorized users.

Balvers MG; Verhoeckx KC; Bijlsma S; Rubingh CM; Meijerink J; Wortelboer HM; Witkamp RF

2012-12-01

213

Sperm status regulates sexual attraction in Caenorhabditis elegans.  

UK PubMed Central (United Kingdom)

Mating behavior of animals is regulated by the sensory stimuli provided by the other sex. Sexually receptive females emit mating signals that can be inhibited by male ejaculate. The genetic mechanisms controlling the release of mating signals and encoding behavioral responses remain enigmatic. Here we present evidence of a Caenorhabditis elegans hermaphrodite-derived cue that stimulates male mating-response behavior and is dynamically regulated by her reproductive status. Wild-type males preferentially mated with older hermaphrodites. Increased sex appeal of older hermaphrodites was potent enough to stimulate robust response from mating-deficient pkd-2 and lov-1 polycystin mutant males. This enhanced response of pkd-2 males toward older hermaphrodites was independent of short-chain ascaroside pheromones, but was contingent on the absence of active sperm in the hermaphrodites. The improved pkd-2 male response toward spermless hermaphrodites was blocked by prior insemination or by genetic ablation of the ceh-18-dependent sperm-sensing pathway of the hermaphrodite somatic gonad. Our work suggests an interaction between sperm and the soma that has a negative but reversible effect on a hermaphrodite-derived mating cue that regulates male mating response, a phenomenon to date attributed to gonochoristic species only.

Morsci NS; Haas LA; Barr MM

2011-12-01

214

Spatial distribution and male mating success of Anopheles gambiae swarms.  

UK PubMed Central (United Kingdom)

BACKGROUND: Anopheles gambiae mates in flight at particular mating sites over specific landmarks known as swarm markers. The swarms are composed of males; females typically approach a swarm, and leave in copula. This mating aggregation looks like a lek, but appears to lack the component of female choice. To investigate the possible mechanisms promoting the evolution of swarming in this mosquito species, we looked at the variation in mating success between swarms and discussed the factors that structure it in light of the three major lekking models, known as the female preference model, the hotspot model, and the hotshot model. RESULTS: We found substantial variation in swarm size and in mating success between swarms. A strong correlation between swarm size and mating success was observed, and consistent with the hotspot model of lek formation, the per capita mating success of individual males did not increase with swarm size. For the spatial distribution of swarms, our results revealed that some display sites were more attractive to both males and females and that females were more attracted to large swarms. While the swarm markers we recognize help us in localizing swarms, they did not account for the variation in swarm size or in the swarm mating success, suggesting that mosquitoes probably are attracted to these markers, but also perceive and respond to other aspects of the swarming site. CONCLUSIONS: Characterizing the mating system of a species helps understand how this species has evolved and how selective pressures operate on male and female traits. The current study looked at male mating success of An. gambiae and discussed possible factors that account for its variation. We found that swarms of An. gambiae conform to the hotspot model of lek formation. But because swarms may lack the female choice component, we propose that the An. gambiae mating system is a lek-like system that incorporates characteristics pertaining to other mating systems such as scramble mating competition.

Diabaté A; Yaro AS; Dao A; Diallo M; Huestis DL; Lehmann T

2011-01-01

215

How multiple mating by females affects sexual selection.  

UK PubMed Central (United Kingdom)

Multiple mating by females is widely thought to encourage post-mating sexual selection and enhance female fitness. We show that whether polyandrous mating has these effects depends on two conditions. Condition 1 is the pattern of sperm utilization by females; specifically, whether, among females, male mating number, m (i.e. the number of times a male mates with one or more females) covaries with male offspring number, o. Polyandrous mating enhances sexual selection only when males who are successful at multiple mating also sire most or all of each of their mates' offspring, i.e. only when Cov(?)(m,o), is positive. Condition 2 is the pattern of female reproductive life-history; specifically, whether female mating number, m, covaries with female offspring number, o. Only semelparity does not erode sexual selection, whereas iteroparity (i.e. when Cov(?)(m,o), is positive) always increases the variance in offspring numbers among females, which always decreases the intensity of sexual selection on males. To document the covariance between mating number and offspring number for each sex, it is necessary to assign progeny to all parents, as well as identify mating and non-mating individuals. To document significant fitness gains by females through iteroparity, it is necessary to determine the relative magnitudes of male as well as female contributions to the total variance in relative fitness. We show how such data can be collected, how often they are collected, and we explain the circumstances in which selection favouring multiple mating by females can be strong or weak.

Shuster SM; Briggs WR; Dennis PA

2013-03-01

216

Exposure to TCDD during development permanently alters reproductive function in male Long Evans rats and hamsters: reduced ejaculated and epididymal sperm numbers and sex accessory gland weights in offspring with normal androgenic status.  

Science.gov (United States)

Prenatal administration of relatively low doses of TCDD alters reproductive development and fertility of the progeny. Fertility was reduced in the progeny of Wistar rats exposed to 0.5 micrograms TCDD/kg/day from Gestational Day (GD) 6 to GD 15. In a three-generation reproduction study, TCDD reduced fertility of Sprague-Dawley rats in the F1 and F2 but not the F0 (no developmental exposure) generation at 0.01 microgram/kg/day in the diet. Furthermore, administration of TCDD on GD 15 (at 0.064 to 1 microgram/kg) both demasculinized and feminized morphology and behavior of Holtzman male rat offspring. Our objectives were to expand the observations of Mably et al. (1992, Toxicol, Appl. Pharmacol. 114, 97-107, 108-117, 118-126) on the effects of gestational administration of a single dose of TCDD to another strain of rat and another species, the hamster. In the first study, Long Evans (LE) hooded rats were dosed by gavage with 1 microgram TCDD/kg on GD 8 (during the period of major organogenesis) or GD 15 (the gestational day used by Mably et al.). In the second study, pregnant Syrian hamsters, a species relatively insensitive to the lethal effects of TCDD, were dosed on GD 11, equivalent to GD 15 in the rat, with TCDD at 2 micrograms/kg. When LE rats were dosed on GD 15, or when hamsters were dosed on GD 11, puberty (preputial separation) was delayed by about 3 days, ejaculated sperm counts were reduced by at least 58%, and epididymal sperm storage was reduced by 38%. Testicular sperm production was less affected. The sex accessory glands were also reduced in size in LE rat offspring treated on GD 15 despite the fact that serum testosterone (T), T production by the testis in vitro, and androgen receptor (AR) levels were not reduced. Some reproductive measures, such as anogenital distance and male sex behavior, were altered by TCDD treatment in rat but not hamster offspring. Since T and AR levels appeared normal in the sex accessory glands and the epididymis following perinatal TCDD exposure, the alterations in these tissues are not likely to have resulted from an alteration of the androgenic status of the male offspring. PMID:7878665

Gray, L E; Kelce, W R; Monosson, E; Ostby, J S; Birnbaum, L S

1995-03-01

217

Exposure to TCDD during development permanently alters reproductive function in male Long Evans rats and hamsters: reduced ejaculated and epididymal sperm numbers and sex accessory gland weights in offspring with normal androgenic status.  

UK PubMed Central (United Kingdom)

Prenatal administration of relatively low doses of TCDD alters reproductive development and fertility of the progeny. Fertility was reduced in the progeny of Wistar rats exposed to 0.5 micrograms TCDD/kg/day from Gestational Day (GD) 6 to GD 15. In a three-generation reproduction study, TCDD reduced fertility of Sprague-Dawley rats in the F1 and F2 but not the F0 (no developmental exposure) generation at 0.01 microgram/kg/day in the diet. Furthermore, administration of TCDD on GD 15 (at 0.064 to 1 microgram/kg) both demasculinized and feminized morphology and behavior of Holtzman male rat offspring. Our objectives were to expand the observations of Mably et al. (1992, Toxicol, Appl. Pharmacol. 114, 97-107, 108-117, 118-126) on the effects of gestational administration of a single dose of TCDD to another strain of rat and another species, the hamster. In the first study, Long Evans (LE) hooded rats were dosed by gavage with 1 microgram TCDD/kg on GD 8 (during the period of major organogenesis) or GD 15 (the gestational day used by Mably et al.). In the second study, pregnant Syrian hamsters, a species relatively insensitive to the lethal effects of TCDD, were dosed on GD 11, equivalent to GD 15 in the rat, with TCDD at 2 micrograms/kg. When LE rats were dosed on GD 15, or when hamsters were dosed on GD 11, puberty (preputial separation) was delayed by about 3 days, ejaculated sperm counts were reduced by at least 58%, and epididymal sperm storage was reduced by 38%. Testicular sperm production was less affected. The sex accessory glands were also reduced in size in LE rat offspring treated on GD 15 despite the fact that serum testosterone (T), T production by the testis in vitro, and androgen receptor (AR) levels were not reduced. Some reproductive measures, such as anogenital distance and male sex behavior, were altered by TCDD treatment in rat but not hamster offspring. Since T and AR levels appeared normal in the sex accessory glands and the epididymis following perinatal TCDD exposure, the alterations in these tissues are not likely to have resulted from an alteration of the androgenic status of the male offspring.

Gray LE Jr; Kelce WR; Monosson E; Ostby JS; Birnbaum LS

1995-03-01

218

Mate and fuse: how yeast cells do it.  

UK PubMed Central (United Kingdom)

Many cells are able to orient themselves in a non-uniform environment by responding to localized cues. This leads to a polarized cellular response, where the cell can either grow or move towards the cue source. Fungal haploid cells secrete pheromones to signal mating, and respond by growing a mating projection towards a potential mate. Upon contact of the two partner cells, these fuse to form a diploid zygote. In this review, we present our current knowledge on the processes of mating signalling, pheromone-dependent polarized growth and cell fusion in Saccharomyces cerevisiae and Schizosaccharomyces pombe, two highly divergent ascomycete yeast models. While the global architecture of the mating response is very similar between these two species, they differ significantly both in their mating physiologies and in the molecular connections between pheromone perception and downstream responses. The use of both yeast models helps enlighten both conserved solutions and species-specific adaptations to a general biological problem.

Merlini L; Dudin O; Martin SG

2013-03-01

219

Mating and Parental Care in Lake Tanganyika's Cichlids.  

Science.gov (United States)

Cichlid fishes of Lake Tanganyika display a variety of mating and parental care behaviors, including polygamous and monogamous mouthbrooding and substrate breeding, cooperative breeding, as well as various alternative reproductive tactics such as sneaking and piracy. Moreover, reproductive behaviors sometimes vary within species both in space and in time. Here, I survey reports on mating and parenting behaviors of Lake Tanganyika cichlid species and address the evolution of mating and parental care patterns and sexual dimorphism. Notes on measures of sexual selection intensity and the difficulties of defining mating systems and estimating selection intensities at species level conclude the essay. PMID:21822482

Sefc, Kristina M

2011-07-21

220

Mating and Parental Care in Lake Tanganyika's Cichlids.  

UK PubMed Central (United Kingdom)

Cichlid fishes of Lake Tanganyika display a variety of mating and parental care behaviors, including polygamous and monogamous mouthbrooding and substrate breeding, cooperative breeding, as well as various alternative reproductive tactics such as sneaking and piracy. Moreover, reproductive behaviors sometimes vary within species both in space and in time. Here, I survey reports on mating and parenting behaviors of Lake Tanganyika cichlid species and address the evolution of mating and parental care patterns and sexual dimorphism. Notes on measures of sexual selection intensity and the difficulties of defining mating systems and estimating selection intensities at species level conclude the essay.

Sefc KM

2011-01-01

 
 
 
 
221

Mating behavior and sexual selection in a polygamous beetle  

Directory of Open Access Journals (Sweden)

Full Text Available Mating behavior and sexual selection in relation to morphometric traits in a polygamous beetle, Glenea cantor (F.) (Coleoptera: Cerambycidae), were investigated. Upon encounter, a male approached a female, mounted her, grasped her terminal abdomen with his hind tarsi, and attempted to mate. Successful mating lasted about 3.5 h. Although all traits measured in females and half of traits in males were significantly correlated with mating success, the primary selection on virgin females was the genital trait, the bursa copulatrix length, and that on males was the body length and hind tarsal length. Longer bursa copulatrix accommodated a larger ejaculate, suggesting that this female trait benefits the male that first mates with the female in terms of increasing ejaculate size to beat subsequent males in sperm competition. Under a female-biased sex ratio, more than 20% of matings failed within 20s after the male genitalia had been inserted into hers, suggesting that males assess genital features of the female before insemination and undertake cryptic male mate choice. Larger males were more capable of grasping females and achieving mating. During the premating struggle the male almost always used his hind tarsi to lift the female terminal abdomen to the position for his genitalia to insert, and as a result, males with longer hind tarsi achieved higher mating success [Current Zoology 59 (2) : 257-264, 2013].?

Wen LU, Qiao WANG, Mingyi TIAN, Jin XU, Jian LV, Aizhi QIN

2013-01-01

222

MATE Module 15: Payloads and Actuators  

Science.gov (United States)

This module from the Marine Advanced Technology Education Center introduces the concept of actuators as they are utilized on a remotely operated vehicle, or ROV. Electric, pneumatic and hydraulic actuators and the control of each are discussed. Students will learn to develop a connection diagram between the MATE ROV Control System and a motor actuator, describe methods used to suppress electrical switching transients while controlling actuators and develop a pneumatic and/or hydraulic control diagram for gripper control and build a simple gripper demonstrating that control. This page includes two PowerPoint files with the documents for in-class instruction.

2013-07-03

223

Mating and re-mating of medflies (Diptera: Tephritidae) in Guatemala: Individual fly marking in field cages  

International Nuclear Information System (INIS)

[en] The sterile insect technique (SIT) depends critically upon the ability of sterilized, released males to locate and mate with wild females. The overall efficiency of the method also depends upon the relative frequencies of re-mating by wild females following first matings to laboratory or wild males. Using a newly devised technique that individually marks the Mediterranean fruit fly, Ceratitis capitata (Wiedemann), a field cage study was undertaken in a Guatemala coffee orchard to record individual fly mating behaviors between each of several laboratory strain and coffee-reared wild flies. Five laboratory strains were tested- a genetic sexing strain examined in sex ratios between 50%-100% sterile males, two standard bisexual strains, and two Fl hybrid strains. The marking technique revealed a substantial amount of information on individual fly mating and re-mating. Wild male flies significantly out-competed each of the lab strains in the first matings with both wild and lab females. Approx. 22% and 3% of wild males and females, respectively, re-mated in the field cages during two consecutive morning observation periods, while 4-8% of lab males, and 2-8% of lab females re-mated, respectively. Male flies from each lab strain averaged significantly shorter copulation times than wild males. Female flies, either lab or wild, tended to re-mate more often if they first mated to a lab male, but the differences were not statistically significant. An index was devised to provide a measure of relative male mating quality. Wild males tended to have higher individual index values than lab strain males. Average values of the latter ranged from ca. half to roughly equal that of wild males. (author)

2002-01-01

224

Assortative mating and differential male mating success in an ash hybrid zone population  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background The structure and evolution of hybrid zones depend mainly on the relative importance of dispersal and local adaptation, and on the strength of assortative mating. Here, we study the influence of dispersal, temporal isolation, variability in phenotypic traits and parasite attacks on the male mating success of two parental species and hybrids by real-time pollen flow analysis. We focus on a hybrid zone population between the two closely related ash species Fraxinus excelsior L. (common ash) and F. angustifolia Vahl (narrow-leaved ash), which is composed of individuals of the two species and several hybrid types. This population is structured by flowering time: the F. excelsior individuals flower later than the F. angustifolia individuals, and the hybrid types flower in-between. Hybrids are scattered throughout the population, suggesting favorable conditions for their local adaptation. We estimate jointly the best-fitting dispersal kernel, the differences in male fecundity due to variation in phenotypic traits and level of parasite attack, and the strength of assortative mating due to differences in flowering phenology. In addition, we assess the effect of accounting for genotyping error on these estimations. Results We detected a very high pollen immigration rate and a fat-tailed dispersal kernel, counter-balanced by slight phenological assortative mating and short-distance pollen dispersal. Early intermediate flowering hybrids, which had the highest male mating success, showed optimal sex allocation and increased selfing rates. We detected asymmetry of gene flow, with early flowering trees participating more as pollen donors than late flowering trees. Conclusion This study provides striking evidence that long-distance gene flow alone is not sufficient to counter-act the effects of assortative mating and selfing. Phenological assortative mating and short-distance dispersal can create temporal and spatial structuring that appears to maintain this hybrid population. The asymmetry of gene flow, with higher fertility and increased selfing, can potentially confer a selective advantage to early flowering hybrids in the zone. In the event of climate change, hybridization may provide a means for F. angustifolia to further extend its range at the expense of F. excelsior.

Gérard Pierre R; Klein Etienne K; Austerlitz Frédéric; Fernández-Manjarrés Juan F; Frascaria-Lacoste Nathalie

2006-01-01

225

Assortative mating and differential male mating success in an ash hybrid zone population.  

UK PubMed Central (United Kingdom)

BACKGROUND: The structure and evolution of hybrid zones depend mainly on the relative importance of dispersal and local adaptation, and on the strength of assortative mating. Here, we study the influence of dispersal, temporal isolation, variability in phenotypic traits and parasite attacks on the male mating success of two parental species and hybrids by real-time pollen flow analysis. We focus on a hybrid zone population between the two closely related ash species Fraxinus excelsior L. (common ash) and F. angustifolia Vahl (narrow-leaved ash), which is composed of individuals of the two species and several hybrid types. This population is structured by flowering time: the F. excelsior individuals flower later than the F. angustifolia individuals, and the hybrid types flower in-between. Hybrids are scattered throughout the population, suggesting favorable conditions for their local adaptation. We estimate jointly the best-fitting dispersal kernel, the differences in male fecundity due to variation in phenotypic traits and level of parasite attack, and the strength of assortative mating due to differences in flowering phenology. In addition, we assess the effect of accounting for genotyping error on these estimations. RESULTS: We detected a very high pollen immigration rate and a fat-tailed dispersal kernel, counter-balanced by slight phenological assortative mating and short-distance pollen dispersal. Early intermediate flowering hybrids, which had the highest male mating success, showed optimal sex allocation and increased selfing rates. We detected asymmetry of gene flow, with early flowering trees participating more as pollen donors than late flowering trees. CONCLUSION: This study provides striking evidence that long-distance gene flow alone is not sufficient to counter-act the effects of assortative mating and selfing. Phenological assortative mating and short-distance dispersal can create temporal and spatial structuring that appears to maintain this hybrid population. The asymmetry of gene flow, with higher fertility and increased selfing, can potentially confer a selective advantage to early flowering hybrids in the zone. In the event of climate change, hybridization may provide a means for F. angustifolia to further extend its range at the expense of F. excelsior.

Gérard PR; Klein EK; Austerlitz F; Fernández-Manjarrés JF; Frascaria-Lacoste N

2006-01-01

226

Kin discrimination and female mate choice in the naked mole-rat Heterocephalus glaber.  

UK PubMed Central (United Kingdom)

Naked mole-rats are fossorial, eusocial rodents that naturally exhibit high levels of inbreeding. Persistent inbreeding in animals often results in a substantial decline in fitness and, thus, dispersal and avoidance of kin as mates are two common inbreeding avoidance mechanisms. In the naked mole-rat evidence for the former has recently been found. Here we address the latter mechanism by investigating kin recognition and female mate choice using a series of choice tests in which the odour, social and mate preferences of females were determined. Discrimination by females appears to be dependent on their reproductive status. Reproductively active females prefer to associate with unfamiliar males, whereas reproductively inactive females do not discriminate. Females do not discriminate between kin and non-kin suggesting that the criterion for recognition is familiarity, not detection of genetic similarity per se. In the wild, naked mole-rats occupy discrete burrow systems and dispersal and mixing with non-kin is thought to be comparatively rare. Thus, recognition by familiarity may function as a highly efficient kin recognition mechanism in the naked mole-rat. A preference by reproductively active females for unfamiliar males is interpreted as inbreeding avoidance. These findings suggest that, despite an evolutionary history of close inbreeding, naked mole-rats may not be exempt from the effects of inbreeding depression and will attempt to outbreed should the opportunity arise.

Clarke FM; Faulkes CG

1999-10-01

227

Kin discrimination and female mate choice in the naked mole-rat Heterocephalus glaber.  

Science.gov (United States)

Naked mole-rats are fossorial, eusocial rodents that naturally exhibit high levels of inbreeding. Persistent inbreeding in animals often results in a substantial decline in fitness and, thus, dispersal and avoidance of kin as mates are two common inbreeding avoidance mechanisms. In the naked mole-rat evidence for the former has recently been found. Here we address the latter mechanism by investigating kin recognition and female mate choice using a series of choice tests in which the odour, social and mate preferences of females were determined. Discrimination by females appears to be dependent on their reproductive status. Reproductively active females prefer to associate with unfamiliar males, whereas reproductively inactive females do not discriminate. Females do not discriminate between kin and non-kin suggesting that the criterion for recognition is familiarity, not detection of genetic similarity per se. In the wild, naked mole-rats occupy discrete burrow systems and dispersal and mixing with non-kin is thought to be comparatively rare. Thus, recognition by familiarity may function as a highly efficient kin recognition mechanism in the naked mole-rat. A preference by reproductively active females for unfamiliar males is interpreted as inbreeding avoidance. These findings suggest that, despite an evolutionary history of close inbreeding, naked mole-rats may not be exempt from the effects of inbreeding depression and will attempt to outbreed should the opportunity arise. PMID:10584337

Clarke, F M; Faulkes, C G

1999-10-01

228

Effect Of Gamma Irradiation On The Mating Activity And Mating Competitiveness Of The Black Cutworm Agrotis Ipsilon (HUFN.) (Lepidoptera : Noctuidae)  

International Nuclear Information System (INIS)

The sterility effects were examined on the P1 generation of the black cutworm; Agrotis ipsilon (Hufn.), after gamma sterilization. The objective was to identify the dose of gamma radiation that would allow for maximum production of partially sterile P1 adults while inducing full sterility in the F1 generation. Full grown pupae of the black cutworm from laboratory culture were irradiated at 75, 100, 125, 150, 175 and 200 Gy. Results indicated that non-significant differences between untreated and treated groups in moth were observed in copula occurred and time of copulation while significant difference was recorded between the treated males and untreated once in spermatophore formation and percentage of females with sperm in their spermatheca at the last two doses. Low percentages of untreated female moths were mated when they were paired with previously mated males than when paired with virgin males. The sequence in which females were mated to an irradiated male did not affect the transfer of spermatophores. The percentage of eggs hatched was higher from the first mated females as compared to the second and third mated females. There were non-significant effects of 0 or 125 Gy exposures on female mating or time in copula. However, significant low percentages of mating of treated and untreated females were occurred with sequentially provided male moths on days 2, 3, to 5 following the first observed female mating. According to the mating competitiveness measured from direct

2011-01-01

229

Alteration in methylation pattern of GATA-4 promoter region in vitamin A-deficient offspring's heart.  

UK PubMed Central (United Kingdom)

Epigenetics might explain correlations between lifestyle and risk of disease. Maternal diet has been shown to dynamically alter epigenetic regulation, including affecting DNA methylation status. This study was designed to test the hypothesis that GATA-4 gene methylation would lead to congenital heart defects in vitamin A-deficient offspring. Ten weaning female rats (VAN group) were fed with a diet which contents 4 IU vitamin A/g diet, while 20 rats (VAD group) were maintained on a diet without vitamin A. After 10 weeks of feeding, all the female rats were mated with normal male rats. The VAN group and a portion of VAD group rats were still given the same diet as before mating, while the rest of the rats from the VAD group (VADS group) were transferred to a diet with enough added vitamin A (10 IU/g diet) for the pregnancy cycle. The embryo hearts were dissected out at embryonic day 13.5 (E13.5) for observation of cardiac development, GATA-4 gene methylation status and the expression of DNA methyltransferases (DNMTs). Embryos from vitamin A-deficient group exhibited a high incidence of cardiac defects. High methylation was present in the CpG loci of GATA-4 gene with a low expression of GATA-4 mRNA from vitamin A-deficient group embryos. Moreover, up-regulation of DNMT1 and down-regulation of DNMT3a and DNMT3b expression were found in this group embryo. These findings show that aberrant methylation is one of key mechanisms to heart defects in vitamin A-deficient offspring. DNMTs play a critical role in this process.

Feng Y; Zhao LZ; Hong L; Shan C; Shi W; Cai W

2013-07-01

230

Courtship Disruptions and Male Mating Strategies: Examples from Female-Defense Mating Systems.  

UK PubMed Central (United Kingdom)

Males frequently interrupt the copulation attempts of other males, and these courtship disruptions may limit the extent to which a few males are able to monopolize mating access to females. Males actively defend sexually receptive females in many species in which females form dense aggregations during the breeding season. Across and within such species there is considerable variation in the mating tactics adopted by males, with males in some cases defending groups of females and in other cases sequentially consorting with individual females. Colonial blackbirds have been central to studying this mating system, and we develop a conceptual model for how courtship disruption may account for variation in male mating tactics in this group. Our model assumes that the frequency of disruptions increases with greater colony size. As a consequence, successful copulations are less likely to occur at large colonies than at small colonies, and males are expected to switch from defending multiple females at the colony to consorting individual females away from it. Results from two species of blackbird support the basic assumptions of this model. In one species, the Montezuma oropendola, disruptions occur rarely and males defend groups of females, whereas in the other species, the yellow-rumped cacique, disruptions are frequent and males defend single females. Moreover, consistent with a key prediction, within each species, males associated with small colonies remain at the colony and defend groups of females, whereas males spend little time defending groups of females at large colonies and rarely attempt copulations there. This model has the potential to explain variation in male mating strategies and female monopolization for other taxa in which females form breeding aggregations.

Webster MS; Robinson SK

1999-12-01

231

Courtship Disruptions and Male Mating Strategies: Examples from Female-Defense Mating Systems.  

Science.gov (United States)

Males frequently interrupt the copulation attempts of other males, and these courtship disruptions may limit the extent to which a few males are able to monopolize mating access to females. Males actively defend sexually receptive females in many species in which females form dense aggregations during the breeding season. Across and within such species there is considerable variation in the mating tactics adopted by males, with males in some cases defending groups of females and in other cases sequentially consorting with individual females. Colonial blackbirds have been central to studying this mating system, and we develop a conceptual model for how courtship disruption may account for variation in male mating tactics in this group. Our model assumes that the frequency of disruptions increases with greater colony size. As a consequence, successful copulations are less likely to occur at large colonies than at small colonies, and males are expected to switch from defending multiple females at the colony to consorting individual females away from it. Results from two species of blackbird support the basic assumptions of this model. In one species, the Montezuma oropendola, disruptions occur rarely and males defend groups of females, whereas in the other species, the yellow-rumped cacique, disruptions are frequent and males defend single females. Moreover, consistent with a key prediction, within each species, males associated with small colonies remain at the colony and defend groups of females, whereas males spend little time defending groups of females at large colonies and rarely attempt copulations there. This model has the potential to explain variation in male mating strategies and female monopolization for other taxa in which females form breeding aggregations. PMID:10600615

Webster; Robinson

1999-12-01

232

Initial Clinical Experience with the HeartMate(R) II Axial-Flow Left Ventricular Assist Device  

Science.gov (United States)

The redesigned HeartMate® II, an axial-flow left ventricular assist device, is simpler, smaller, and easier to operate than are pulsatile pumps. These design characteristics should make the HeartMate II more reliable and durable and broaden the eligible population base. We implanted the HeartMate II in 43 patients (average age, 42 yr). The indication for use was bridge-to-heart transplantation in 26 patients and destination therapy in 17. The average duration of device support was 258 days (range, 1–761 days), and cumulative duration, more than 31 patient-years. Hemodynamic function improved in all patients during support. By 48 hours after implantation, the mean cardiac index had increased from 1.9±0.27 L/(min·m2) (baseline) to 3.5±0.8 L/(min·m2), and the pulmonary capillary wedge pressure had decreased from 24.8±11 mmHg to 18.5±5.3 mmHg. Of the 43 patients, 35 were discharged from the hospital. Support is ongoing in 27 patients (longest duration, >700 days). Nine patients died during support. Four patients had sufficient heart recovery to undergo pump explantation. Three patients underwent transplantation. One patient underwent device replacement after the pump driveline was fractured in a skateboarding accident; the device was removed in another patient because of a pump-pocket infection after 749 days of support. Of the 10 patients in whom the HeartMate II replaced a failed HeartMate I, 8 were discharged from the hospital. We have seen excellent results with use of the HeartMate II. Functional status and quality of life have greatly improved in patients who survived the perioperative period.

Frazier, O. H.; Gemmato, Courtney; Myers, Timothy J.; Gregoric, Igor D.; Radovancevic, Brano; Loyalka, Pranav; Kar, Biswajit

2007-01-01

233

Sexual antagonism for testosterone maintains multiple mating behaviour.  

UK PubMed Central (United Kingdom)

1. The persistence of multiple mating remains one of the fundamental questions in evolutionary biology. In theory, multiple mating is predicted to improve female fitness cumulatively through direct and/or genetic benefits. However, intra-locus sexual conflicts may potentially constrain or even eliminate these benefits owing to the gender load imposed by sexually antagonistic selection. 2. Here, we tested whether sexually antagonistic selection can maintain the variance in multiple mating behaviour of bank voles (Myodes glareolus) by manipulating the hormone testosterone through artificial selection in the laboratory. Among mammals, testosterone is a sexually dimorphic fitness-related trait under selection and is known to affect mating behaviour. We conducted mating trials in which females derived from family-based selection of testosterone were sequentially paired with four males of different testosterone profiles. 3. We show that artificial selection for high testosterone increased the mating rate of males, but clearly decreased the number of partners that females mated with (and vice versa). Because multiple mating was beneficial for the reproductive success of both sexes, as evidenced by the positive Bateman gradients, the divergent evolutionary interests of testosterone between the sexes can maintain this polygynandrous mating system. 4. Our results highlight how mating rate is concordantly selected in both sexes; however, it is largely influenced by testosterone, which is under sexually antagonistic selection. 5. This study is the first one to emphasise the direct and indirect effects of the endocrine system not only on reproductive physiology and behaviour but also for the evolution of genetic mating strategies in mammals.

Mokkonen M; Koskela E; Mappes T; Mills SC

2012-01-01

234

Environmental influences on mate preferences as assessed by a scenario manipulation experiment.  

UK PubMed Central (United Kingdom)

Many evolutionary psychology studies have addressed the topic of mate preferences, focusing particularly on gender and cultural differences. However, the extent to which situational and environmental variables might affect mate preferences has been comparatively neglected. We tested 288 participants in order to investigate the perceived relative importance of six traits of an ideal partner (wealth, dominance, intelligence, height, kindness, attractiveness) under four different hypothetical scenarios (status quo/nowadays, violence/post-nuclear, poverty/resource exhaustion, prosperity/global well-being). An equal number of participants (36 women, 36 men) was allotted to each scenario; each was asked to allocate 120 points across the six traits according to their perceived value. Overall, intelligence was the trait to which participants assigned most importance, followed by kindness and attractiveness, and then by wealth, dominance and height. Men appraised attractiveness as more valuable than women. Scenario strongly influenced the relative importance attributed to traits, the main finding being that wealth and dominance were more valued in the poverty and post-nuclear scenarios, respectively, compared to the other scenarios. Scenario manipulation generally had similar effects in both sexes, but women appeared particularly prone to trade off other traits for dominance in the violence scenario, and men particularly prone to trade off other traits for wealth in the poverty scenario. Our results are in line with other correlational studies of situational variables and mate preferences, and represent strong evidence of a causal relationship of environmental factors on specific mate preferences, corroborating the notion of an evolved plasticity to current ecological conditions. A control experiment seems to suggest that our scenarios can be considered as realistic descriptions of the intended ecological conditions.

Marzoli D; Moretto F; Monti A; Tocci O; Roberts SC; Tommasi L

2013-01-01

235

Environmental influences on mate preferences as assessed by a scenario manipulation experiment.  

Science.gov (United States)

Many evolutionary psychology studies have addressed the topic of mate preferences, focusing particularly on gender and cultural differences. However, the extent to which situational and environmental variables might affect mate preferences has been comparatively neglected. We tested 288 participants in order to investigate the perceived relative importance of six traits of an ideal partner (wealth, dominance, intelligence, height, kindness, attractiveness) under four different hypothetical scenarios (status quo/nowadays, violence/post-nuclear, poverty/resource exhaustion, prosperity/global well-being). An equal number of participants (36 women, 36 men) was allotted to each scenario; each was asked to allocate 120 points across the six traits according to their perceived value. Overall, intelligence was the trait to which participants assigned most importance, followed by kindness and attractiveness, and then by wealth, dominance and height. Men appraised attractiveness as more valuable than women. Scenario strongly influenced the relative importance attributed to traits, the main finding being that wealth and dominance were more valued in the poverty and post-nuclear scenarios, respectively, compared to the other scenarios. Scenario manipulation generally had similar effects in both sexes, but women appeared particularly prone to trade off other traits for dominance in the violence scenario, and men particularly prone to trade off other traits for wealth in the poverty scenario. Our results are in line with other correlational studies of situational variables and mate preferences, and represent strong evidence of a causal relationship of environmental factors on specific mate preferences, corroborating the notion of an evolved plasticity to current ecological conditions. A control experiment seems to suggest that our scenarios can be considered as realistic descriptions of the intended ecological conditions. PMID:24069291

Marzoli, Daniele; Moretto, Francesco; Monti, Aura; Tocci, Ornella; Roberts, S Craig; Tommasi, Luca

2013-09-12

236

The evolution and maintenance of mixed mating systems  

Science.gov (United States)

The evolution and maintenance of mixed mating systems, where both selfing and outcrossing occur in a population, remains an important unresolved question in evolutionary biology. On the one hand the majority of theoretically models predict mixed mating systems to be evolutionary unstable with popula...

237

Mating flights select for symmetry in honeybee drones ( Apis mellifera)  

Science.gov (United States)

Males of the honeybee ( Apis mellifera) fly to specific drone congregation areas (DCAs), which virgin queens visit in order to mate. From the thousands of drones that are reared in a single colony, only very few succeed in copulating with a queen, and therefore, a strong selection is expected to act on adult drones during their mating flights. In consequence, the gathering of drones at DCAs may serve as an indirect mate selection mechanism, assuring that queens only mate with those individuals having a better flight ability and a higher responsiveness to the queen’s visual and chemical cues. Here, we tested this idea relying on wing fluctuating asymmetry (FA) as a measure of phenotypic quality. By recapturing marked drones at a natural DCA and comparing their size and FA with a control sample of drones collected at their maternal hives, we were able to detect any selection on wing size and wing FA occurring during the mating flights. Although we found no solid evidence for selection on wing size, wing FA was found to be significantly lower in the drones collected at the DCA than in those collected at the hives. Our results demonstrate the action of selection during drone mating flights for the first time, showing that developmental stability can influence the mating ability of honeybee drones. We therefore conclude that selection during honeybee drone mating flights may confer some fitness advantages to the queens.

Jaffé, Rodolfo; Moritz, Robin F. A.

2010-03-01

238

Mating flights select for symmetry in honeybee drones (Apis mellifera).  

Science.gov (United States)

Males of the honeybee (Apis mellifera) fly to specific drone congregation areas (DCAs), which virgin queens visit in order to mate. From the thousands of drones that are reared in a single colony, only very few succeed in copulating with a queen, and therefore, a strong selection is expected to act on adult drones during their mating flights. In consequence, the gathering of drones at DCAs may serve as an indirect mate selection mechanism, assuring that queens only mate with those individuals having a better flight ability and a higher responsiveness to the queen's visual and chemical cues. Here, we tested this idea relying on wing fluctuating asymmetry (FA) as a measure of phenotypic quality. By recapturing marked drones at a natural DCA and comparing their size and FA with a control sample of drones collected at their maternal hives, we were able to detect any selection on wing size and wing FA occurring during the mating flights. Although we found no solid evidence for selection on wing size, wing FA was found to be significantly lower in the drones collected at the DCA than in those collected at the hives. Our results demonstrate the action of selection during drone mating flights for the first time, showing that developmental stability can influence the mating ability of honeybee drones. We therefore conclude that selection during honeybee drone mating flights may confer some fitness advantages to the queens. PMID:20012931

Jaffé, Rodolfo; Moritz, Robin F A

2009-12-15

239

Chemical Mating Attractants in the Queen Honey Bee.  

UK PubMed Central (United Kingdom)

Drone attraction to ether extracts of virgin queens (Apis mellifera L.) demonstrated that chemical communication enables the drones to orient themselves to queens during mating flights. The primary source of queen mating attractants is the mandibular glands. Fractionation of mandibular gland lipids yielded several attractive fractions that may act jointly. One fraction was queen substance (9-oxodec-2-enoic acid).

Gary NE

1962-06-01

240

Costs of mating and egg production in female Callosobruchus chinensis.  

UK PubMed Central (United Kingdom)

Costs of reproduction include the costs of mating and egg production. Specific techniques such as irradiation or genetic mutation have been used to divide the expense into costs of mating and egg production in previous studies. We tried to divide the costs in the adzuki bean beetle, Callosobruchus chinensis (Coleoptera: Bruchidae), which needs some kinds of bean as an oviposition substrate. Mated females that were not allowed to lay eggs had a shorter life span than virgin females, but they had a longer life span than mated females that were allowed to lay eggs. The results showed two independent significant costs, mating and egg production, on the life span in C. chinensis. Costs of mating, however, include the costs of sexual harassment by males and copulation itself, and we need further studies to divide the costs. The present method for dividing the cost of reproduction into costs of mating and egg production can be applied to a broad taxonomic range of insect species, and thus it will be a useful model system for inter-specific comparisons of costs of mating and egg production.

Yanagi S; Miyatake T

2003-09-01

 
 
 
 
241

Comment on "Illusions promote mating success in great bowerbirds".  

UK PubMed Central (United Kingdom)

Kelley and Endler (Reports, 20 January 2012, p. 335) claim that male great bowerbirds construct a visual illusion, using display object gradients, that affects mating success. We argue that they provide inadequate statistical support for their hypothesis, inappropriately exclude important data, and do not consider other display traits that explain mating success. We propose a more plausible alternative hypothesis to explain display object patterns.

Borgia G; Coyle BJ; Keagy J

2012-07-01

242

Mating duration and sperm precedence in the spider Linyphia triangularis  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In spiders, copulations often take much longer than needed to fertilize the female’s complement of eggs, and the likelihood that a female mates again may depend on the duration of the first male’s copulation since the mating itself may induce lack of receptivity in the female. Also, the result of sp...

Weldingh, Ditte Louise; Toft, Søren; Larsen, Ole Næsbye

243

Two-sided assortative mating for a single locus.  

UK PubMed Central (United Kingdom)

Most models previously considered for assortative mating were such that no change in gene frequencies occurred, or that one-sided assortative mating was occurring. Two-sided assortative mating is more realistic for human populations, and in this paper a model of two-sided assortative mating is analysed for two autosomal alleles with dominance, an important case for human genetics. The concept of a relative probability of matin between two phenotypes is used, and this variable can take into account factors such as different propensities for assortment in the various phenotypes and so forth. It is shown that the gene frequency may vary from generation to generation and conditions for the establishment of a stable polymorphism are given. For instance, Stanton (1947) has considered a special case of two-sided assortative mating with two autosomal alleles and a constant correlation between mates, where the value expressed by the heterozygote is numerically exactly half-way between the values exhibited by the two homozygotes. Also he has considered a special form of assortative mating, where the probability of occurrence of matings between the same homozygotes has been increased in each generation by the same constant factor as the probability of occurrence of matings between different homozygotes has been decreased. The probability of occurrence of matings involving heterozygotes remains the same as if mating were random. For this particular model the frequency of the genotypes in those who mate in generation t is the same as for the general population in generation t, but the genotypic frequencies change from generation to generation, reaching an equilibrium value. Stark (1976) has also considered a similar model to Stanton's (1947), the major difference occurring in the construction of the mating frequencies, which in this case occurs according to the canonical decomposition of the 2-way table of mating frequencies. Stark shows the correspondence between the results for this model and those given by Malécot (1939, 1948). The results for all these models depend on the particular values assigned to the genotypes. Also these models could be extended as outlined in this article for the case of two autosomal alleles with dominance.

Wilson SR

1976-11-01

244

Homothallic and heterothallic mating in the opportunistic pathogen Candida albicans.  

Science.gov (United States)

Candida albicans is the most common fungal pathogen in humans, causing both debilitating mucosal infections and potentially life-threatening systemic infections. Until recently, C. albicans was thought to be strictly asexual, existing only as an obligate diploid. A cryptic mating cycle has since been uncovered in which diploid a and alpha cells undergo efficient cell and nuclear fusion, resulting in tetraploid a/alpha mating products. Whereas mating between a and alpha cells has been established (heterothallism), we report here two pathways for same-sex mating (homothallism) in C. albicans. First, unisexual populations of a cells were found to undergo autocrine pheromone signalling and same-sex mating in the absence of the Bar1 protease. In both C. albicans and Saccharomyces cerevisiae, Bar1 is produced by a cells and inactivates mating pheromone alpha, typically secreted by alpha cells. C. albicans Deltabar1 a cells were shown to secrete both a and alpha mating pheromones; alpha-pheromone activated self-mating in these cells in a process dependent on Ste2, the receptor for alpha-pheromone. In addition, pheromone production by alpha cells was found to promote same-sex mating between wild-type a cells. These results establish that homothallic mating can occur in C. albicans, revealing the potential for genetic exchange even within unisexual populations of the organism. Furthermore, Bar1 protease has an unexpected but pivotal role in determining whether sexual reproduction can potentially be homothallic or is exclusively heterothallic. These findings also have implications for the mode of sexual reproduction in related species that propagate unisexually, and indicate a role for specialized sexual cycles in the survival and adaptation of pathogenic fungi. PMID:19675652

Alby, Kevin; Schaefer, Dana; Bennett, Richard J

2009-08-13

245

Homothallic and heterothallic mating in the opportunistic pathogen Candida albicans.  

UK PubMed Central (United Kingdom)

Candida albicans is the most common fungal pathogen in humans, causing both debilitating mucosal infections and potentially life-threatening systemic infections. Until recently, C. albicans was thought to be strictly asexual, existing only as an obligate diploid. A cryptic mating cycle has since been uncovered in which diploid a and alpha cells undergo efficient cell and nuclear fusion, resulting in tetraploid a/alpha mating products. Whereas mating between a and alpha cells has been established (heterothallism), we report here two pathways for same-sex mating (homothallism) in C. albicans. First, unisexual populations of a cells were found to undergo autocrine pheromone signalling and same-sex mating in the absence of the Bar1 protease. In both C. albicans and Saccharomyces cerevisiae, Bar1 is produced by a cells and inactivates mating pheromone alpha, typically secreted by alpha cells. C. albicans Deltabar1 a cells were shown to secrete both a and alpha mating pheromones; alpha-pheromone activated self-mating in these cells in a process dependent on Ste2, the receptor for alpha-pheromone. In addition, pheromone production by alpha cells was found to promote same-sex mating between wild-type a cells. These results establish that homothallic mating can occur in C. albicans, revealing the potential for genetic exchange even within unisexual populations of the organism. Furthermore, Bar1 protease has an unexpected but pivotal role in determining whether sexual reproduction can potentially be homothallic or is exclusively heterothallic. These findings also have implications for the mode of sexual reproduction in related species that propagate unisexually, and indicate a role for specialized sexual cycles in the survival and adaptation of pathogenic fungi.

Alby K; Schaefer D; Bennett RJ

2009-08-01

246

Site fidelity, mate fidelity, and breeding dispersal in American kestrels  

Science.gov (United States)

We assessed mate fidelity, nest-box fidelity, and breeding dispersal distances of American Kestrels (falco sparverius) nesting in boxes in southwestern Idaho from 1990 through 2006. Seventy-seven percent of boxes had different males and 87% had different females where nest-box occupants were identified in consecutive years. High turnover rates were partly a result of box-switching. Forty-eight percent of males and 58% of females that nested within the study area in successive years used different boxes. The probability of changing boxes was unrelated to gender, nesting success in the prior year, or years of nesting experience. Breeding dispersal distances for birds that moved to different boxes averaged 2.2 km for males (max = 22 km) and 3.2 km for females (max = 32 km). Approximately 70% of birds that nested in consecutive years on the study area had a different mate in the second year. Mate fidelity was related to box fidelity but not to prior nesting success or years of nesting experience. Mate changes occurred 32% of the time when the previous mate was known to be alive and nesting in the area. Kestrels that switched mates and boxes did not improve or decrease their subsequent nesting success. Kestrels usually switched to mates with less experience and lower lifetime productivity than their previous mates. The costs of switching boxes and mates were low, and there were no obvious benefits to fidelity. The cost of "waiting" for a previous mate that might have died could be high in species with high annual mortality.

Steenhof, K.; Peterson, B. E.

2009-01-01

247

Regulation of yeast mating-type interconversion: feedback control of HO gene expression by the mating-type locus.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The ultimate product of yeast mating-type interconversion is a stable a/alpha diploid cell. A haploid cell carrying the HO gene gives rise to a diploid cell in a two-step process: first, the cell switches mating type as a result of genetic rearrangement (cassette substitution) catalyzed by HO; then,...

Jensen, R; Sprague, G F; Herskowitz, I

248

Dopaminergic neurons in the brain and dopaminergic innervation of the albumen gland in mated and virgin helisoma duryi (mollusca: pulmonata)  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Dopamine was shown to stimulate the perivitelline fluid secretion by the albumen gland. Even though the albumen gland has been shown to contain catecholaminergic fibers and its innervation has been studied, the type of catecholamines, distribution of fibers and the precise source of this neural innervation has not yet been deduced. This study was designed to address these issues and examine the correlation between dopamine concentration and the sexual status of snails. Results Dopaminergic neurons were found in all ganglia except the pleural and right parietal, and their axons in all ganglia and major nerves of the brain. In the albumen gland dopaminergic axons formed a nerve tract in the central region, and a uniform net in other areas. Neuronal cell bodies were present in the vicinity of the axons. Dopamine was a major catecholamine in the brain and the albumen gland. No significant difference in dopamine quantity was found when the brain and the albumen gland of randomly mating, virgin and first time mated snails were compared. Conclusions Our results represent the first detailed studies regarding the catecholamine innervation and quantitation of neurotransmitters in the albumen gland. In this study we localized catecholaminergic neurons and axons in the albumen gland and the brain, identified these neurons and axons as dopaminergic, reported monoamines present in the albumen gland and the brain, and compared the dopamine content in the brain and the albumen gland of randomly mating, virgin and first time mated snails.

Kiehn Lana; Saleuddin Saber; Lange Angela

2001-01-01

249

Mating Instabilities Lead to Sympatric Speciation  

CERN Multimedia

One of the most challenging issues of evolutionary biology concerns speciation, the emergence of new species from an initial one. The huge amount of species found in nature demands a simple and robust mechanism. Yet, no consensus has been reached concerning a reasonable disruptive selection mechanism that prevents mixing genes among the emerging species, especially when they live in sympatry. Usually it is assumed that females select males according to their displaying traits, but males perform no selection on female traits. However, recent experimental evidence accumulates towards the existence of male choice. Here we propose a robust mechanism for sympatric speciation, based on the assumption that sexual selection operates in two directions: selection of males by females and of females by males. Complex mating instabilities emerge, creating differential fitness depending on the individuals displaying traits and preferences. When a secondary sexual trait is introduced in a population, due to mutations, the a...

Almeida, C R; Almeida, Catarina R.; Abreu, Fern\\~ao Vistulo de

2002-01-01

250

Desenvolvimento de gelatina funcional de erva-mate Development of functional yerba-mate jelly  

Directory of Open Access Journals (Sweden)

Full Text Available O objetivo deste estudo foi desenvolver formulações para gelatina funcional com extrato de erva-mate verde e fibras solúveis como inulina (INU), frutooligossacarídeos (FOS) e a polidextrose (PD), avaliando o efeito desses ingredientes na gelatina funcional por meio da análise física da textura (firmeza, consistência e coesividade), análise sensorial (sabor e preferência de compra) e composição química. As formulações INU, PD e composição INU/PD/FOS apresentaram textura desejável para uma sobremesa de gelatina, não diferindo (P>0,05) do padrão com sacarose. Pela análise sensorial, a gelatina funcional com INU obteve o maior índice hedônico para sabor e preferência de compra acima de 70%, superior ao padrão. Considerando os resultados obtidos neste estudo, a aplicação tecnológica do extrato de erva-mate verde e das fibras solúveis apresenta evidente potencial para o desenvolvimento de alimentos saudáveis e funcionais.The objective of this study was to develop formulations for functional jelly with extract of green yerba-mate and soluble fibers as inulin (INU), fructooligosaccharides (FOS) and polidextrose (PD), evaluating the effect of those ingredients in the functional jelly through texture physical analysis (firmness, consistence, cohesiveness), sensorial analysis (flavor and purchase preference) and chemical composition. The formulations INU, PD and composition INU/PD/FOS presented desirable texture for jelly dessert and not differing (P>0.05) of the reference standard with sucrose. For the sensorial analysis the functional jelly with INU obtained the largest index hedonic for flavor and purchase preference above 70%, higher than the reference standard. Considering the results obtained in this study, the technological application of green yerba-mate extract and of soluble fibers, presents evident potential for the development of healthy and functional foods.

Kleber Alves Santos Berté; Dayane Rosalyn Izidoro; Fabiana Lemos Goularte Dutra; Rosemary Hoffmann-Ribani

2011-01-01

251

Desenvolvimento de gelatina funcional de erva-mate/ Development of functional yerba-mate jelly  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese O objetivo deste estudo foi desenvolver formulações para gelatina funcional com extrato de erva-mate verde e fibras solúveis como inulina (INU), frutooligossacarídeos (FOS) e a polidextrose (PD), avaliando o efeito desses ingredientes na gelatina funcional por meio da análise física da textura (firmeza, consistência e coesividade), análise sensorial (sabor e preferência de compra) e composição química. As formulações INU, PD e composição INU/PD/FOS apresen (more) taram textura desejável para uma sobremesa de gelatina, não diferindo (P>0,05) do padrão com sacarose. Pela análise sensorial, a gelatina funcional com INU obteve o maior índice hedônico para sabor e preferência de compra acima de 70%, superior ao padrão. Considerando os resultados obtidos neste estudo, a aplicação tecnológica do extrato de erva-mate verde e das fibras solúveis apresenta evidente potencial para o desenvolvimento de alimentos saudáveis e funcionais. Abstract in english The objective of this study was to develop formulations for functional jelly with extract of green yerba-mate and soluble fibers as inulin (INU), fructooligosaccharides (FOS) and polidextrose (PD), evaluating the effect of those ingredients in the functional jelly through texture physical analysis (firmness, consistence, cohesiveness), sensorial analysis (flavor and purchase preference) and chemical composition. The formulations INU, PD and composition INU/PD/FOS presente (more) d desirable texture for jelly dessert and not differing (P>0.05) of the reference standard with sucrose. For the sensorial analysis the functional jelly with INU obtained the largest index hedonic for flavor and purchase preference above 70%, higher than the reference standard. Considering the results obtained in this study, the technological application of green yerba-mate extract and of soluble fibers, presents evident potential for the development of healthy and functional foods.

Berté, Kleber Alves Santos; Izidoro, Dayane Rosalyn; Dutra, Fabiana Lemos Goularte; Hoffmann-Ribani, Rosemary

2011-02-01

252

Análisis microbiológico en yerba mate compuesta/ Microbiological analysis in composite yerba mate  

Scientific Electronic Library Online (English)

Full Text Available Abstract in spanish Se estudiaron 41 muestras de yerba mate compuesta (YMC) de Posadas, Misiones, Argentina: 21 muestras conteniendo menos de 15% de hierbas (YMC15%). El análisis microbiológico se realizó mediante recuentos de bacterias aeróbicas mesófilas totales (BAMT), coliformes totales (CT), coliformes termotolerantes (CTT), mohos y levaduras (RML) y detección de Escherichia coli. Los recuentos microbiológicos presentaron valores en promedio para YMC15%: BAMT=3,4x106 UFC/g, CT=6. (more) 8x102 NMP/g, CTT=3.4 x101 NMP/g y RML=1,0x105 UFC/g. En YMC>15% se detectó Escherichia coli. YMC presenta una importante contaminación microbiana, siendo mayor en YMC>15%. Los parámetros microbiológicos analizados son superiores a los reportados en yerba mate elaborada destacando la importancia de realizar controles microbiológicos en YMC. Abstract in english Forty one samples of composite yerba mate (CYM) from Posadas, Misiones, Argentina were studied: 21 samples containing less than 15% of herbs (CYM 15%). The analysis was performed by microbiological counts of total mesophilic aerobic bacteria (TMAB), total coliforms (TC), coliforms thermotolerant (CTT), moulds and yeasts (MY) and Escherichia coli detection. Microbiological counts showed average values CYM15%: TMAB=3.4x106 CFU/g, TC=6.8x102 MPN/g, NMP CTT=3.4x101 CFU/g and (more) MY=1.0x105 CFU/g. In YMC>15% Escherichia coli was detected. CYM presents significant microbial contamination, being higher in CYM>15%. Microbiological parameters analyzed are higher than those reported in elaborated yerba mate, showing the importance of microbiological controls to CYM.

Jerke, G; Horianski, M.A; Bargardi, S; Martínez, M.L

2011-06-01

253

Effect of {sup 60}CO radiation processing in mate (Ilex paraguariensis); Efeito do processamento por radiacao de {sup 60}CO na erva-mate (Ilex paraguariensis)  

Energy Technology Data Exchange (ETDEWEB)

The mate (Ilex paraguariensis), a native species from South America, is mainly consumed as typical beverage called chimarrao and terere. An important problem that has been afflicting this product since a long time is its natural fungal contamination responsible to affect its physical, health and nutritional qualities. In order to improve this product quality, radiation processing can be effective in reducing pathogens levels, with minimal nutritional and sensory changes. The aim of this study was to evaluate the effectiveness of gamma radiation from {sup 60}Co at doses 0, 3, 5, 7 and 10kGy in reducing fungal contamination in mate, as well as analyze its nutritional and sensory characteristics. The following methodologies were applied: analysis of yeast and mold, total phenolic compounds analysis, antioxidant analysis, quantification of phenolic compounds and xanthines by liquid chromatography and sensory analysis. Microbiological analysis showed a decreasing molds and yeasts growth with increasing radiation doses. Regardless of the radiation dose applied there were no decrease of total phenolic compounds in both infusions. Chimarrao samples irradiated with 7 and 10kGy showed a decrease in the DPPH radical-scavenger activity, nevertheless for terere samples, there were no significant difference. Chimarrao chromatographic profile did not show a variation on xanthines quantification, however a 10kGy radiation dose caused a change to phenolic compounds quantitative profile. Terere samples did not show any significant difference to any analyzed compounds. Sensory analysis did not exhibit a significant difference between irradiated and non irradiated chimarrao samples, as well as between irradiated and non irradiated terere samples. It could be concluded that gamma radiation processing of mate may be a feasible alternative to industry, since there was a reduction on fungal contamination, without changes in sensory qualities and with minimum alterations in quantitative and qualitative profile of bioactive compounds. (author)

Furgeri, Camilo

2009-07-01

254

Lifetime number of mates interacts with female age to determine reproductive success in female guppies.  

UK PubMed Central (United Kingdom)

In many species, mating with multiple males confers benefits to females, but these benefits may be offset by the direct and indirect costs associated with elevated mating frequency. Although mating frequency (number of mating events) is often positively associated with the degree of multiple mating (actual number of males mated), most studies have experimentally separated these effects when exploring their implications for female fitness. In this paper I describe an alternative approach using the guppy Poecilia reticulata, a livebearing freshwater fish in which females benefit directly and indirectly from mating with multiple males via consensual matings but incur direct and indirect costs of mating as a consequence of male sexual harassment. In the present study, females were experimentally assigned different numbers of mates throughout their lives in order to explore how elevated mating frequency and multiple mating combine to influence lifetime reproductive success (LRS) and survival (i.e. direct components of female fitness). Under this mating design, survival and LRS were not significantly affected by mating treatment, but there was a significant interaction between brood size and reproductive cycle (a correlate of female age) because females assigned to the high mating treatment produced significantly fewer offspring later in life compared to their low-mating counterparts. This negative effect of mating treatment later in life may be important in these relatively long-lived fishes, and this effect may be further exacerbated by the known cross-generational fitness costs of sexual harassment in guppies.

Evans JP

2012-01-01

255

Lifetime number of mates interacts with female age to determine reproductive success in female guppies.  

Science.gov (United States)

In many species, mating with multiple males confers benefits to females, but these benefits may be offset by the direct and indirect costs associated with elevated mating frequency. Although mating frequency (number of mating events) is often positively associated with the degree of multiple mating (actual number of males mated), most studies have experimentally separated these effects when exploring their implications for female fitness. In this paper I describe an alternative approach using the guppy Poecilia reticulata, a livebearing freshwater fish in which females benefit directly and indirectly from mating with multiple males via consensual matings but incur direct and indirect costs of mating as a consequence of male sexual harassment. In the present study, females were experimentally assigned different numbers of mates throughout their lives in order to explore how elevated mating frequency and multiple mating combine to influence lifetime reproductive success (LRS) and survival (i.e. direct components of female fitness). Under this mating design, survival and LRS were not significantly affected by mating treatment, but there was a significant interaction between brood size and reproductive cycle (a correlate of female age) because females assigned to the high mating treatment produced significantly fewer offspring later in life compared to their low-mating counterparts. This negative effect of mating treatment later in life may be important in these relatively long-lived fishes, and this effect may be further exacerbated by the known cross-generational fitness costs of sexual harassment in guppies. PMID:23071816

Evans, Jonathan P

2012-10-12

256

Restrictive mating by females on black grouse leks.  

Science.gov (United States)

In bird species with pair bonds, extra-pair matings could allow females to choose genetically superior males. This is not needed in lekking species because female choice is not constrained by pairing opportunities. However, polyandry has been reported in most lekking species studied so far. Using 12 microsatellite loci, we determined the paternity of 135 broods of black grouse sampled between 2001 and 2005 (970 hatchlings and 811 adult birds genotyped). The paternity assignments were combined to lek observations to investigate the mating behaviour of black grouse females. About 10% of the matings seemed to take place with males displaying solitarily. Forty per cent of the copulations between males displaying on the studied leks and radio-tagged females were not recorded. This was due to difficulties in identifying the females and because our observations did not cover all the possible time for matings. However, females of the undetected copulations had chosen males that were already known to be successful on the leks. There was a strong consistency between the observations and true paternity, even when the copulation was disturbed by a neighbouring male. Multiple mating and multiple paternities were rare. We can now confidently ascertain that most females mate only once with one male for the whole clutch. This mating behaviour requires that a single insemination is sufficient to fertilize a clutch and that females can determine whether the sperm has been successfully transferred. Grouse Tetraoninae with many lekking species may be the only bird taxon that has evolved these traits. PMID:17850264

Lebigre, C; Alatalo, R V; Siitari, H; Parri, S

2007-09-10

257

Post-mating clutch piracy in an amphibian.  

Science.gov (United States)

Female multiple mating and alternative mating systems can decrease the opportunity for sexual selection. Sperm competition is often the outcome of females mating with multiple males and has been observed in many animals, and alternative reproductive systems are widespread among species with external fertilization and parental care. Multiple paternity without associated complex behaviour related to mating or parental care is also seen in simultaneously spawning amphibians and fishes that release gametes into water. Here we report 'clutch piracy' in a montane population of the common frog Rana temporaria, a reproductive behaviour previously unknown in vertebrates with external fertilization. Males of this species clasp the females and the pair deposits one spherical clutch of eggs. No parental care is provided. 'Pirate' males search for freshly laid clutches, clasp them as they would do a female and fertilize the eggs that were left unfertilized by the 'parental' male. This behaviour does not seem to be size-dependent, and some males mate with a female and perform clutch piracy in the same season. Piracy affected 84% of the clutches and in some cases increased the proportion of eggs fertilized, providing direct fitness benefits both for the pirate males and the females. Sexual selection--probably caused by a strong male-biased sex ratio--occurs in this population, as indicated by size-assortative mating; however, clutch piracy may reduce its impact. This provides a good model to explore how alternative mating strategies can affect the intensity of sexual selection. PMID:15372032

Vieites, David R; Nieto-Román, Sandra; Barluenga, Marta; Palanca, Antonio; Vences, Miguel; Meyer, Axel

2004-09-16

258

What uses are mating types? The "developmental switch" model.  

UK PubMed Central (United Kingdom)

Why mating types exist at all is subject to much debate. Among hypotheses, mating types evolved to control organelle transmission during sexual reproduction, or to prevent inbreeding or same-clone mating. Here I review data from a diversity of taxa (including ciliates, algae, slime molds, ascomycetes, and basidiomycetes) to show that the structure and function of mating types run counter the above hypotheses. I argue instead for a key role in triggering developmental switches. Genomes must fulfill a diversity of alternative programs along the sexual cycle. As a haploid gametophyte, an individual may grow vegetatively (through haploid mitoses), or initiate gametogenesis and mating. As a diploid sporophyte, similarly, it may grow vegetatively (through diploid mitoses) or initiate meiosis and sporulation. Only diploid sporophytes (and not haploid gametophytes) should switch on the meiotic program. Similarly, only haploid gametophytes (not sporophytes) should switch on gametogenesis and mating. And they should only do so when other gametophytes are ready to do the same in the neighborhood. As argued here, mating types have evolved primarily to switch on the right program at the right moment.

Perrin N

2012-04-01

259

Endocrine control of mating instinct in Dysdercus koenigii (Hemiptera: Pyrrhocoridae).  

Science.gov (United States)

Five pairs of median and 1 pair of lateral neurosecretory cell groups occur in the protocerebrum of Dysdercus koenigii, a hemipteran pest on the ladies finger plant (Hibiscus esculentus). The lateral neurosecretory cells (LNSC) become active prior to, and at the time of commencement of mating and release their secretion within 24 h of commencement. The female never mates again after laying eggs and the LNSC also never become active. It is believed that LNSC secretion induces the urge for mating in the freshly emerged female and the lateral groups of NSC form the receptivity centre in the brain. PMID:1171778

Sharma, U; Sahni, S L; Sinha, D P

1975-08-15

260

Endocrine control of mating instinct in Dysdercus koenigii (Hemiptera: Pyrrhocoridae).  

UK PubMed Central (United Kingdom)

Five pairs of median and 1 pair of lateral neurosecretory cell groups occur in the protocerebrum of Dysdercus koenigii, a hemipteran pest on the ladies finger plant (Hibiscus esculentus). The lateral neurosecretory cells (LNSC) become active prior to, and at the time of commencement of mating and release their secretion within 24 h of commencement. The female never mates again after laying eggs and the LNSC also never become active. It is believed that LNSC secretion induces the urge for mating in the freshly emerged female and the lateral groups of NSC form the receptivity centre in the brain.

Sharma U; Sahni SL; Sinha DP

1975-08-01

 
 
 
 
261

Male inbreeding status affects female fitness in a seed-feeding beetle.  

Science.gov (United States)

Inbreeding generally reduces male mating activity such that inbred males are less successful in male-male competition. Inbred males can also have smaller accessory glands, transfer less sperm and produce sperm that are less motile, less viable or have a greater frequency of abnormalities, all of which can reduce the fertilization success and fitness of inbred males relative to outbred males. However, few studies have examined how male inbreeding status affects the fitness of females with whom they mate. In this study, we examine the effect of male inbreeding status (inbreeding coefficient f = 0.25 vs. f = 0) on the fecundity, adult longevity and the fate of eggs produced by outbred females in the seed-feeding beetle, Callosobruchus maculatus. Females mated to inbred males were less likely to lay eggs. Of those that laid eggs, females mated to inbred males laid 6-12% fewer eggs. Females mated to inbred males lived on average 5.4% longer than did females mated to outbred males, but this effect disappeared when lifetime fecundity was used as a covariate in the analysis. There was no effect of male inbreeding status on the proportion of a female's eggs that developed or hatched, and no evidence that inbred males produced smaller nuptial gifts. However, ejaculates of inbred males contained 17-33% fewer sperm, on average, than did ejaculates of outbred males. Our study demonstrates that mating with inbred males has significant direct consequences for the fitness of female C. maculatus, likely mediated by effects of inbreeding status on the number of sperm in male ejaculates. Direct effects of male inbreeding status on female fitness should be more widely considered in theoretical models and empirical studies of mate choice. PMID:21995954

Fox, Charles W; Xu, J; Wallin, W G; Curtis, C L

2011-10-13

262

Cloning of the Lentinula edodes B mating-type locus and identification of the genetic structure controlling B mating.  

UK PubMed Central (United Kingdom)

During the life cycle of heterothallic tetrapolar Agaricomycetes such as Lentinula edodes (Berk.) Pegler, the mating type system, composed of unlinked A and B loci, plays a vital role in controlling sexual development and resulting formation of the fruit body. L. edodes is produced worldwide for consumption and medicinal purposes, and understanding its sexual development is therefore of great importance. A considerable amount of mating type factors has been indicated over the past decades but few genes have actually been identified, and no complete genetic structures of L. edodes B mating-type loci are available. In this study, we cloned the matB regions from two mating compatible L. edodes strains, 939P26 and 939P42. Four pheromone receptors were identified on each new matB region, together with three and four pheromone precursor genes in the respective strains. Gene polymorphism, phylogenetic analysis and distribution of pheromone receptors and pheromone precursors clearly indicate a bipartite matB locus, each sublocus containing a pheromone receptor and one or two pheromone precursors. Detailed sequence comparisons of genetic structures between the matB regions of strains 939P42, 939P26 and a previously reported strain SUP2 further supported this model and allowed identification of the B mating type subloci borders. Mating studies confirmed the control of B mating by the identified pheromone receptors and pheromones in L. edodes.

Wu L; van Peer A; Song W; Wang H; Chen M; Tan Q; Song C; Zhang M; Bao D

2013-12-01

263

Alteration processes  

International Nuclear Information System (INIS)

This session gathers 22 articles (posters) dealing with: natural systems evidence for the alteration of clay under alkaline conditions; stress corrosion cracking of carbon steel exposed to deep geological environment; the microstructure of compacted argillite submitted to an alkaline plume; the effect of the high pH alkaline solutions on the mineralogy and leachate chemistry of the Boom clay batch experiment at 60 deg. C; the effects of grouting and shotcreting on the backfill geochemistry of a KBS-3 HLNW repository; the evaluation of geochemical scenarios for iron/argillite interactions in a deep waste disposal: a density study on reaction rates and gas partial pressures; smectite interaction with metal iron; insights into long-term alteration of bentonite-cement system based on coupled mass-transport/chemical reaction analysis; the effects of alkaline alteration on water diffusivity in montmorillonite gels: NMR study; the investigation of smectite alteration and form of iron corrosion products in compacted bentonite being in contact with carbon steel for ten years; the TEM characterization of the FEBEX bentonite after two-years contact with iron corrosion products; the concrete/FEBEX bentonite interaction: preliminary results on short-term column experiments; IPHAP: background information on Philippine bentonites, hyper-alkaline waters and potential analogue sites; the Simulation of the degradation of a concrete/clay interface: influence of temperature, unsaturated conditions and porosity variations; the integrated study of 6 years in-situ steels/ argillite interactions at Tournemire by mineralogical and modelling approaches; the study of nuclear glass / canister corrosion products / clay system by means of integral modular material tests; the influence of dissolution/precipitation kinetics on the porosity clogging effect during cement/clay interactions; the alkaline perturbation into the Tournemire argillite: Structural and mineralogical studies of a 15 years in-situ propagation; the geochemical behavior of clay material under neutral and alkaline conditions at low temperature; a migration technique applied to study alteration of compacted sand-bentonite mixture in contact with concrete; the hydrothermal alteration of Callovo- Oxfordian argillite from the Paris basin by neutral and alkaline solutions at 150 deg. C and 300 deg. C and in the presence of iron metal; and some thermodynamic considerations on the behavior of Kerogen under conditions of alkaline perturbation

2007-01-01

264

Alteration processes  

Energy Technology Data Exchange (ETDEWEB)

This session gathers 22 articles (posters) dealing with: natural systems evidence for the alteration of clay under alkaline conditions; stress corrosion cracking of carbon steel exposed to deep geological environment; the microstructure of compacted argillite submitted to an alkaline plume; the effect of the high pH alkaline solutions on the mineralogy and leachate chemistry of the Boom clay batch experiment at 60 deg. C; the effects of grouting and shotcreting on the backfill geochemistry of a KBS-3 HLNW repository; the evaluation of geochemical scenarios for iron/argillite interactions in a deep waste disposal: a density study on reaction rates and gas partial pressures; smectite interaction with metal iron; insights into long-term alteration of bentonite-cement system based on coupled mass-transport/chemical reaction analysis; the effects of alkaline alteration on water diffusivity in montmorillonite gels: NMR study; the investigation of smectite alteration and form of iron corrosion products in compacted bentonite being in contact with carbon steel for ten years; the TEM characterization of the FEBEX bentonite after two-years contact with iron corrosion products; the concrete/FEBEX bentonite interaction: preliminary results on short-term column experiments; IPHAP: background information on Philippine bentonites, hyper-alkaline waters and potential analogue sites; the Simulation of the degradation of a concrete/clay interface: influence of temperature, unsaturated conditions and porosity variations; the integrated study of 6 years in-situ steels/ argillite interactions at Tournemire by mineralogical and modelling approaches; the study of nuclear glass / canister corrosion products / clay system by means of integral modular material tests; the influence of dissolution/precipitation kinetics on the porosity clogging effect during cement/clay interactions; the alkaline perturbation into the Tournemire argillite: Structural and mineralogical studies of a 15 years in-situ propagation; the geochemical behavior of clay material under neutral and alkaline conditions at low temperature; a migration technique applied to study alteration of compacted sand-bentonite mixture in contact with concrete; the hydrothermal alteration of Callovo- Oxfordian argillite from the Paris basin by neutral and alkaline solutions at 150 deg. C and 300 deg. C and in the presence of iron metal; and some thermodynamic considerations on the behavior of Kerogen under conditions of alkaline perturbation.

Savage, D.; Benbow, S.; Watson, C.; Takase, H.; Oda, C.; Honda, A.; Didot, A.; Herms, E.; Bataillon, C.; Chene, J.; Crusset, D.; Cuisinier, O.; Masrouri, F.; Pelletier, M.; Villieras, F.; Mosser-Ruck, R.; Honty, M.; Van Geet, M.; Craen, M. de; Arcos, D.; Luna, M.; Duro, L.; Trotignon, L.; Hairapetian, T.; Bildstein, O.; Jullien, M.; Osack' y, M.; Sucha, V.; Madejova, J.; Puskelova, L.; Komadel, P.; Miglierini, M.; Majernik, A.; Uhlik, P.; Yamaguchi, T.; Yamada, F.; Negishi, K.; Hoshino, S.; Mukai, M.; Tanaka, T.; Nakayama, S.; Takahashi, T.; Ohkubo, T.; Ikeda, Y.; Ishidera, T.; Ueno, K.; Kurosawa, S.; Suyama, T.; Torres, E.; Turrero, M.J.; Martin, P.L.; Escribano, A.; Baldonedo, J.L.; Escribano, A.; Arcilla, C.A.; Paguican, E.; Ferrer, C.; Alexander, W.R.; McKinley, I.G.; Miyoshi, S.; Burnol, A.; Dupros, F.; Spycher, N.; Xu, T.; Blanc, P.; Gaucher, E.C.; Gaudin, A.; Gaboreau, S.; Tinseau, E.; Bartier, D.; Petit, S.; Beaufort, D.; Minet, Y.; Lartigue, J.E.; Lemmens, K.; Marty, N.; Tournassat, C.; Gaucher, E.C.; Burnol, A.; Giffaut, E.; Tinseau, E.; Cabrera, J.; Bartier, D.; Techer, I.; Lemius, S.; Made, B.; Michaux, L.; Sugiyama, T.; Tsuji, Y.; Mosser-Ruck, R.; Richard, L.; Cathelineau, M.; Richard, L

2007-07-01

265

Size-assortative mating and sexual size dimorphism are predictable from simple mechanics of mate-grasping behavior  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background A major challenge in evolutionary biology is to understand the typically complex interactions between diverse counter-balancing factors of Darwinian selection for size assortative mating and sexual size dimorphism. It appears that rarely a simple mechanism could provide a major explanation of these phenomena. Mechanics of behaviors can predict animal morphology, such like adaptations to locomotion in animals from various of taxa, but its potential to predict size-assortative mating and its evolutionary consequences has been less explored. Mate-grasping by males, using specialized adaptive morphologies of their forelegs, midlegs or even antennae wrapped around female body at specific locations, is a general mating strategy of many animals, but the contribution of the mechanics of this wide-spread behavior to the evolution of mating behavior and sexual size dimorphism has been largely ignored. Results Here, we explore the consequences of a simple, and previously ignored, fact that in a grasping posture the position of the male's grasping appendages relative to the female's body is often a function of body size difference between the sexes. Using an approach taken from robot mechanics we model coercive grasping of females by water strider Gerris gracilicornis males during mating initiation struggles. We determine that the male optimal size (relative to the female size), which gives the males the highest grasping force, properly predicts the experimentally measured highest mating success. Through field sampling and simulation modeling of a natural population we determine that the simple mechanical model, which ignores most of the other hypothetical counter-balancing selection pressures on body size, is sufficient to account for size-assortative mating pattern as well as species-specific sexual dimorphism in body size of G. gracilicornis. Conclusion The results indicate how a simple and previously overlooked physical mechanism common in many taxa is sufficient to account for, or importantly contribute to, size-assortative mating and its consequences for the evolution of sexual size dimorphism.

Han Chang S; Jablonski Piotr G; Kim Beobkyun; Park Frank C

2010-01-01

266

Morphological change in the early stages of the mating process of Rhodosporidium toruloides.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The events which occur in the early stages of the mating process of the yeast Rhodosporidium toruloides between strains M-919 (mating type A) and M-1057 (mating type a) were investigated. In preliminary experiments we determined the frequency of mating by two newly designed methods: the liquid cultu...

Abe, K; Kusaka, I; Fukui, S

267

Efeito da Densidade de Presas e do Acasalamento na Taxa de Predação de Fêmeas de Podisus nigrispinus (Dallas) (Heteroptera: Pentatomidae) em Condições de Laboratório e Campo/ Effect of Prey Density and Mating Status on Predation Rate of Females of Podisus nigrispinus (Dallas) (Heteroptera: Pentatomidae) in Laboratory and Field Conditions  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese Avaliou-se a taxa de predação de fêmeas virgens ou acasaladas de Podisus nigrispinus (Dallas) em diferentes densidades de lagartas de Alabama argillacea (Huebner) em condições de laboratório e de campo. Em laboratório, empregaram-se potes plásticos de 500 ml contendo fêmeas do predador, uma folha de algodão e lagartas de A. argillacea (50 ± 10 mg) nas densidades de uma, duas, quatro, oito e 16 lagartas. No campo, algodoeiros na fase de florescimento foram engai (more) olados, sendo empregadas as mesmas densidades de lagartas que no laboratório. Em ambas as condições, as fêmeas de P. nigrispinus apresentaram ganho de peso e aumento de sua taxa de predação com o aumento da densidade de lagartas de A. argillacea, mas com valores maiores para fêmeas em laboratório. Nas duas condições, o ganho de peso e a taxa de predação foram semelhantes para fêmeas virgens ou acasaladas. No campo, P. nigrispinus explorou 94,7% e 21,2% da área foliar disponível na menor e maior densidade de presas, respectivamente. O tempo de manipulação e a taxa de ataque estimadas foram de 3,37 ± 0,82h e de 0,076 ± 0,013h-1 em laboratório, e de 3,33 ± 0,93h e de 0,017 ± 0,003h-1 em campo. A resposta funcional em laboratório e no campo foi caracterizada como do Tipo II. Os números observados e estimados de lagartas predadas pelo modelo foram significativamente correlacionados com as condições de laboratório (r = 0,78) e de campo (r = 0,70). Abstract in english The predation rate of unmated and mated females of Podisus nigrispinus (Dallas) was evaluated on different densities of Alabama argillacea (Huebner) caterpillars (50 ± 10 mg), in laboratory and field conditions. In the laboratory, the predator females were maintained in 500 ml plastic jars with five different densities of prey (one, two, four, eight, and 16). In the field, caterpillars at the same densities were caged on flowering cotton plants. Under both conditions, fe (more) males gained weight and increased the predation rate when the availability of prey increased, although higher values were obtained for females kept in the laboratory. Weight gain and predation rate did not differ between unmated and mated females under both conditions. In the field, P. nigrispinus searched 94.7% of the available foliar area under low prey density, and 21.2% under high prey density. The estimated handling time and attack rate were, respectively, 3.37 ± 0,82h and 0.076 ± 0.013h-1 in the laboratory, and 3.33 ± 0.93h and 0.017 ± 0.003h-1 in the field. The functional response corresponded to a type II for both conditions. The number of killed caterpillars observed and estimated by the model were highly correlated for both laboratory (r = 0.78) and field (r = 0.70) conditions.

OLIVEIRA, JOSÉ E.M.; TORRES, JORGE B.; CARRANO-MOREIRA, ALBERTO F.; ZANUNCIO, JOSÉ C.

2001-12-01

268

Sib mating without inbreeding in the longhorn crazy ant  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Sib matings increase homozygosity and, hence, the frequency of detrimental phenotypes caused by recessive deleterious alleles. However, many species have evolved adaptations that prevent the genetic costs associated with inbreeding. We discovered that the highly invasive longhorn crazy ant, Paratrec...

Pearcy, Morgan; Goodisman, Michael A. D.; Keller, Laurent

269

Protecting artificial team-mates : more seems like less  

DEFF Research Database (Denmark)

Previous research on conversational, competitive, and cooperative systems suggests that people respond differently to humans and AI agents in terms of perception and evaluation of observed team-mate behavior. However, there has not been research examining the relationship between participants' protective behavior toward human/AI team-mates and their beliefs about their behavior. A study was conducted in which 32 participants played two sessions of a cooperative game, once with a "presumed" human and once with an AI team-mate; players could "draw fire" from a common enemy by "yelling" at it. Overwhelmingly, players claimed they "drew fire" on behalf of the presumed human more than for the AI team-mate; logged data indicates the opposite. The main contribution of this paper is to provide evidence of the mismatch in player beliefs about their actions and actual behavior with humans or agents and provides possible explanations for the differences.

Merritt, Timothy; McGee, Kevin

270

Do as we wish: Parental tactics of mate choice manipulation.  

UK PubMed Central (United Kingdom)

The mate choices of children do not always meet with the approval of their parents. As a consequence, the latter employ a battery of tactics that they use to manipulate the mating behavior of the former. This paper offers the first taxonomy of parental tactics of mate choice manipulation. In particular, in Study 1, 57 semi-structured interviews revealed 72 acts that parents employ to influence their children, and 27 that they employ to influence their children's partners. In Study 2, 405 parents rated how likely they were to use these acts to influence their daughters' and sons' mate choices. Factor analysis of participants' responses revealed 12 manipulation tactics that parents use on their children, and four manipulation tactics that they use on their children's partners.

Apostolou M

2013-01-01

271

Mating and Parental Care in Lake Tanganyika's Cichlids  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Cichlid fishes of Lake Tanganyika display a variety of mating and parental care behaviors, including polygamous and monogamous mouthbrooding and substrate breeding, cooperative breeding, as well as various alternative reproductive tactics such as sneaking and pi...

Sefc, Kristina M.

272

Signal transduction during mating and meiosis in S. pombe  

DEFF Research Database (Denmark)

When starved, the fission yeast Schizosaccharomyces pombe responds by producing mating factors or pheromones that signal to cells of the opposite sex to initiate mating. Like its distant relative Saccharomyces cerevisiae, cells of the two mating types of S. pombe each produce a distinct pheromone that binds to receptors on the opposite cell type to induce the morphological changes required for mating. While the pathways are basically very similar in the two yeasts, pheromone signalling in S. pombe differs in several important ways from that of the more familiar budding yeast. In this article, Olaf Nielsen describes the pheromones and their effects in S. pombe, and compares the signalling pathways of the two yeasts.

Nielsen, O; Nielsen, Olaf

1993-01-01

273

Social inclusion facilitates risky mating behavior in men.  

UK PubMed Central (United Kingdom)

Although past research has reliably established unique effects of social exclusion on human cognition and behavior, the current research focuses on the unique effects of social inclusion. Recent evidence indicates that social inclusion leads to enhanced prioritization of reproductive interests. The current study extends these findings by showing that the pursuit of these inclusion-induced reproductive goals occurs in sex-specific ways. Across three experiments, social inclusion led men, but not women, to endorse riskier, more aggressive mating strategies compared to control and socially excluded participants. Specifically, included men were more likely to endorse sexual aggression (Experiment 1), high-risk mate poaching behaviors (Experiment 2), and high-risk mate retention tactics (Experiment 3). These results demonstrate that the experience of social inclusion can affect sex-differentiated preferences for risky mating strategies.

Sacco DF; Brown CM; Young SG; Bernstein MJ; Hugenberg K

2011-07-01

274

Social inclusion facilitates risky mating behavior in men.  

Science.gov (United States)

Although past research has reliably established unique effects of social exclusion on human cognition and behavior, the current research focuses on the unique effects of social inclusion. Recent evidence indicates that social inclusion leads to enhanced prioritization of reproductive interests. The current study extends these findings by showing that the pursuit of these inclusion-induced reproductive goals occurs in sex-specific ways. Across three experiments, social inclusion led men, but not women, to endorse riskier, more aggressive mating strategies compared to control and socially excluded participants. Specifically, included men were more likely to endorse sexual aggression (Experiment 1), high-risk mate poaching behaviors (Experiment 2), and high-risk mate retention tactics (Experiment 3). These results demonstrate that the experience of social inclusion can affect sex-differentiated preferences for risky mating strategies. PMID:21518810

Sacco, Donald F; Brown, Christina M; Young, Steven G; Bernstein, Michael J; Hugenberg, Kurt

2011-04-25

275

Constructing rational maps with cluster points using the mating operation  

CERN Multimedia

In this article, we show that all admissible rational maps with fixed or period two cluster cycles can be constructed by the mating of polynomials. We also investigate the polynomials which make up the matings that construct these rational maps. In the one cluster case, one of the polynomials must be an $n$-rabbit and in the two cluster case, one of the maps must be either $f$, a "double rabbit", or $g$, a secondary map which lies in the wake of the double rabbit $f$. There is also a very simple combinatorial way of classifiying the maps which must partner the aforementioned polynomials to create rational maps with cluster cycles. Finally, we also investigate the multiplicities of the shared matings arising from the matings in the paper.

Sharland, Thomas

2011-01-01

276

Sexual dimorphism in stature (SDS), jealousy and mate retention.  

UK PubMed Central (United Kingdom)

Previous research has investigated the manner in which absolute height impacts on jealousy and mate retention. Although relative height is also important, little information exists about the potential influence of sexual dimorphism in stature (SDS) within established relationships. The current study investigated the relationship between SDS and the satisfaction, jealousy and mate retention behaviors reported by men and women. Heterosexual men (n = 98) and women (n = 102) completed a questionnaire. Men in high SDS relationships reported the lowest levels of cognitive and behavioral jealousy, although the impact of SDS on relationship satisfaction was less clear. SDS was not associated with the overall use of mate retention strategies; SDS did however affect the use of three specific strategies (vigilance, monopolization of time, love and care). SDS did not affect women's relationship satisfaction, jealousy (cognitive, behavioral, or emotional) or the use of mate retention strategies (with the exception of resource display).

Brewer G; Riley C

2010-01-01

277

Parent-Offspring Conflict over Short-Term Mating Strategies  

Directory of Open Access Journals (Sweden)

Full Text Available Individuals engage in short-term mating strategies that enable them to obtain fitness benefits from casual relationships. These benefits, however, count for less and cost more to their parents. On this basis three hypotheses are tested. First, parents and offspring are likely to disagree over short-term mating strategies, with the former considering these as less acceptable than the latter. Second, parents are more likely to disapprove of the short-term mating strategies of their daughters than of their sons. Finally, mothers and fathers are expected to agree on how much they disagree over the short-term mating strategies of their children. Evidence from a sample of 148 Greek-Cypriot families (140 mothers, 105 fathers, 119 daughters, 77 sons) provides support for the first two hypotheses and partial support for the third hypothesis. The implications of these findings for understanding family dynamics are further discussed.

Menelaos Apostolou; Spyroulla Georgiou

2011-01-01

278

More than just a pretty face and a hot body: multiple cues in mate-choice.  

UK PubMed Central (United Kingdom)

Mate preferences have been well studied in social and evolutionary psychology. In two studies (N = 490), using two different measurement techniques, we examined mate preferences for the body and the face in the context of other traits. Results replicated prior research on mate preferences across the sex of the participant and mating duration but clarified the nature of preferences for physical attractiveness. Generally, physical attractiveness was a necessity in short-term mating and for men and traits like kindness were a necessity in long-term mating and for women. Men wanted a short-term mate who had a good body, likely because that body advertises fertility whereas both sexes wanted a mate with a nice face for a long-term mate, which is likely because the face is a cue based on structural properties related to health. Sex and mating-duration differences on preferences for attractive faces and bodies were robust to differences in measurement technique.

Jonason PK; Raulston T; Rotolo A

2012-03-01

279

More than just a pretty face and a hot body: multiple cues in mate-choice.  

Science.gov (United States)

Mate preferences have been well studied in social and evolutionary psychology. In two studies (N = 490), using two different measurement techniques, we examined mate preferences for the body and the face in the context of other traits. Results replicated prior research on mate preferences across the sex of the participant and mating duration but clarified the nature of preferences for physical attractiveness. Generally, physical attractiveness was a necessity in short-term mating and for men and traits like kindness were a necessity in long-term mating and for women. Men wanted a short-term mate who had a good body, likely because that body advertises fertility whereas both sexes wanted a mate with a nice face for a long-term mate, which is likely because the face is a cue based on structural properties related to health. Sex and mating-duration differences on preferences for attractive faces and bodies were robust to differences in measurement technique. PMID:22468419

Jonason, Peter K; Raulston, Tara; Rotolo, Ashley

280

High levels of carcinogenic polycyclic aromatic hydrocarbons in mate drinks.  

UK PubMed Central (United Kingdom)

BACKGROUND: Drinking mate has been associated with cancers of the esophagus, oropharynx, larynx, lung, kidney, and bladder. We conducted this study to determine whether drinking mate could lead to substantial exposure to polycyclic aromatic hydrocarbons (PAH), including known carcinogens, such as benzo[a]pyrene. METHODS: The concentrations of 21 individual PAHs were measured in dry leaves of eight commercial brands of yerba mate and in infusions made with hot (80 degrees C) or cold (5 degrees C) water. Measurements were done using gas chromatography/mass spectrometry, with deuterated PAHs as the surrogates. Infusions were made by adding water to the leaves, removing the resulting infusion after 5 min, and then adding more water to the remaining leaves. This process was repeated 12 times for each infusion temperature. RESULTS: The total concentrations of the 21 PAHs in different brands of yerba mate ranged from 536 to 2,906 ng/g dry leaves. Benzo[a]pyrene concentrations ranged from 8.03 to 53.3 ng/g dry leaves. For the mate infusions prepared using hot water and brand 1, 37% (1,092 of 2,906 ng) of the total measured PAHs and 50% (25.1 of 50 ng) of the benzo[a]pyrene content were released into the 12 infusions. Similar results were obtained for other hot and cold infusions. CONCLUSION: Very high concentrations of carcinogenic PAHs were found in yerba mate leaves and in hot and cold mate infusions. Our results support the hypothesis that the carcinogenicity of mate may be related to its PAH content.

Kamangar F; Schantz MM; Abnet CC; Fagundes RB; Dawsey SM

2008-05-01

 
 
 
 
281

[Assortative mating among individuals with refractive errors of the eye  

UK PubMed Central (United Kingdom)

Negative assortative mating for refractive errors of the eyes of 1241 married couples was discovered in the urban region of the South Moravian region. 46 married couples were myopic, 55 hyperopic, 73 astigmatic, 175 had combinations of refractive errors, 261 were emetropic and 631 were mixed. Negative assortative mating is highly significant (chi-square P < or = 0.001). It is more significant for urban population. Positive selection for emetropic married couples plays more important role in urban peoples than in citizens.

Vrba M

2002-11-01

282

Comments on the Penrose-Stanton model of assortative mating.  

Science.gov (United States)

A single-locus model of assortative mating proposed by Penrose and extended by Stanton is analysed. It is shown that the formulae giving values of correlations between males and relatives derived by Stanton apply to a general class of symmetric, non-selective mating schemes in equilibrium when genotypes have additive values. The canonical form of Stanton's system is derived, revealing that the assignment of additive values of genotypes does not apply also to the canonical vectors. PMID:921217

Stark, A E

1977-07-01

283

Comments on the Penrose-Stanton model of assortative mating.  

UK PubMed Central (United Kingdom)

A single-locus model of assortative mating proposed by Penrose and extended by Stanton is analysed. It is shown that the formulae giving values of correlations between males and relatives derived by Stanton apply to a general class of symmetric, non-selective mating schemes in equilibrium when genotypes have additive values. The canonical form of Stanton's system is derived, revealing that the assignment of additive values of genotypes does not apply also to the canonical vectors.

Stark AE

1977-07-01

284

Male Mating Signaling in Social Dilemma Games  

DEFF Research Database (Denmark)

According to sexual selection theory and costly signaling theory, men benefit from signaling costly mate qualities to attractive women. To date, several studies have investigated whether men use conspicuous altruism to attract women, but the findings are mixed. This study investigated whether men being observed by an attractive woman engage in competitive economic altruism in three social dilemma games—the Dictator Game, Trust Game (2nd mover), and Public Goods Game—in comparison to men being observed by a non-attractive woman. Results showed that altruistic contributions in the games were not significantly larger in the attractive observer group than in the non-attractive observer group. Exploratory analyses did reveal, however, that amongst participants with an attractive observer only, dispositional generosity had a strongly positive effect on altruism while dispositional dominance had a negative effect on altruism. Moderating effects of key individual differences suggest that the mixed findings within theempirical literature may be attributed to the existence of multiple male courtship signaling strategies. As such, the findings suggest a promising way for future studies to identify different signaling strategies, but until the findings can be replicated with specific hypothesis-driven studies they should be considered with caution.

Jensen, Niels Holm

2013-01-01

285

Lateral transfer of mating system in Stemphylium.  

Science.gov (United States)

The fungal genus Stemphylium (Ascomycota) contains selfing species that evolved from outcrossing ancestors. To find out how selfing originated, we analyzed the Stemphylium MAT loci that regulate sexual reproduction in ascomycetes and compared MAT structures and phylogeny with a multigene Stemphylium species phylogeny. We found that some Stemphylium species' MAT loci contained a single gene, either MAT1-1 or MAT1-2, whereas others contained a unique fusion of the MAT1-1 and MAT1-2 regions. In all fused MAT regions, MAT1-1 was inverted and joined to a forward-oriented MAT1-2 region. As in the closely related Cochliobolus, Stemphylium species with fused MAT regions were able to self. Structural and phylogenetic analyses of the MAT loci showed that the selfing-conferring fused MAT regions were monophyletic with strong support. However, in an organismal phylogeny of Stemphylium species based on 106 isolates and four loci unrelated to mating, selfing arose in two clades, each time with strong support. Isolates with identical fused MAT regions were present in both clades. We showed that a one-time origin of the fused MAT loci, followed by a horizontal transfer across lineages, was compatible with the data. Another group of selfers in Stemphylium only had forward-oriented MAT1-1 at their MAT loci, constituting an additional and third origin of selfing in Stemphylium. PMID:16055562

Inderbitzin, Patrik; Harkness, Jennifer; Turgeon, B Gillian; Berbee, Mary L

2005-07-29

286

Lateral transfer of mating system in Stemphylium.  

UK PubMed Central (United Kingdom)

The fungal genus Stemphylium (Ascomycota) contains selfing species that evolved from outcrossing ancestors. To find out how selfing originated, we analyzed the Stemphylium MAT loci that regulate sexual reproduction in ascomycetes and compared MAT structures and phylogeny with a multigene Stemphylium species phylogeny. We found that some Stemphylium species' MAT loci contained a single gene, either MAT1-1 or MAT1-2, whereas others contained a unique fusion of the MAT1-1 and MAT1-2 regions. In all fused MAT regions, MAT1-1 was inverted and joined to a forward-oriented MAT1-2 region. As in the closely related Cochliobolus, Stemphylium species with fused MAT regions were able to self. Structural and phylogenetic analyses of the MAT loci showed that the selfing-conferring fused MAT regions were monophyletic with strong support. However, in an organismal phylogeny of Stemphylium species based on 106 isolates and four loci unrelated to mating, selfing arose in two clades, each time with strong support. Isolates with identical fused MAT regions were present in both clades. We showed that a one-time origin of the fused MAT loci, followed by a horizontal transfer across lineages, was compatible with the data. Another group of selfers in Stemphylium only had forward-oriented MAT1-1 at their MAT loci, constituting an additional and third origin of selfing in Stemphylium.

Inderbitzin P; Harkness J; Turgeon BG; Berbee ML

2005-08-01

287

Cytonuclear interactions and the economics of mating in seed beetles.  

Science.gov (United States)

Recent studies have uncovered an abundance of nonneutral cytoplasmic genetic variation within species, which suggests that we should no longer consider the cytoplasm an idle intermediary of evolutionary change. Nonneutrality of cytoplasmic genomes is particularly intriguing, given that these genomes are maternally transmitted. This means that the fate of any given cytoplasmic genetic mutation is directly tied to its performance when expressed in females. For this reason, it has been hypothesized that cytoplasmic genes will coevolve via a sexually antagonistic arms race with the biparentally transmitted nuclear genes with which they interact. We assess this prediction, examining the intergenomic contributions to the costs and benefits of mating in Callosobruchus maculatus females subjected to a mating treatment with three classes (kept virgin, mated once, or forced to cohabit with a male). We find no evidence that the economics of mating are determined by interactions between cytoplasmic genes expressed in females and nuclear genes expressed in males and, therefore, no support for a sexually antagonistic intergenomic arms race. The cost of mating to females was, however, shaped by an interaction between the cytoplasmic and nuclear genes expressed within females. Thus, cytonuclear interactions are embroiled in the economics of mating. PMID:20524843

Dowling, Damian K; Meerupati, Tejashwari; Arnqvist, Göran

2010-08-01

288

Cytonuclear interactions and the economics of mating in seed beetles.  

UK PubMed Central (United Kingdom)

Recent studies have uncovered an abundance of nonneutral cytoplasmic genetic variation within species, which suggests that we should no longer consider the cytoplasm an idle intermediary of evolutionary change. Nonneutrality of cytoplasmic genomes is particularly intriguing, given that these genomes are maternally transmitted. This means that the fate of any given cytoplasmic genetic mutation is directly tied to its performance when expressed in females. For this reason, it has been hypothesized that cytoplasmic genes will coevolve via a sexually antagonistic arms race with the biparentally transmitted nuclear genes with which they interact. We assess this prediction, examining the intergenomic contributions to the costs and benefits of mating in Callosobruchus maculatus females subjected to a mating treatment with three classes (kept virgin, mated once, or forced to cohabit with a male). We find no evidence that the economics of mating are determined by interactions between cytoplasmic genes expressed in females and nuclear genes expressed in males and, therefore, no support for a sexually antagonistic intergenomic arms race. The cost of mating to females was, however, shaped by an interaction between the cytoplasmic and nuclear genes expressed within females. Thus, cytonuclear interactions are embroiled in the economics of mating.

Dowling DK; Meerupati T; Arnqvist G

2010-08-01

289

Identifying Alterity and Altering Identity  

Directory of Open Access Journals (Sweden)

Full Text Available Negative attitudes towards foreign cultures among certain categories of people in majority Islamic countries are often the result of their representations of the Other, their conception of alterity, of their identity and the relation between them, their vision of the implications of the confrontation with/or coexistence of different cultures in the same physical space or through mediated spaces. These representations have become a culture in its own right, giving birth to a categorisation of people within the same society and of peoples of the world. This paper will attempt to reveal the way this culture dichotomy operates and will analyse the mode its ideological base defines the dichotomy of alterity/identity. It will also suggest directions of reflexion towards the possibilities of forging a counter-culture which can stand as a new form of liberating discourse.

Abdelghani Nait Brahim

2011-01-01

290

Smectite alteration  

International Nuclear Information System (INIS)

This report contains the proceedings of a second workshop in Washington DC December 8-9, 1983 on the alteration of smectites intended for use as buffer materials in the long-term containment of nuclear wastes. It includes extended summaries of all presentations and a transcript of the detailed scientific discussion. The discussions centered on three main questions: What is the prerequisite for and what is the precise mechanism by which smectite clays may be altered to illite. What are likly sources of potassium with respect to the KBS project. Is it likely that the conversion of smectite to illite will be of importance in the 10 5 to the 10 6 year time frame. The workshop was convened to review considerations and conclusions in connection to these questions and also to broaden the discussion to consider the use of smectite clays as buffer materials for similar applications in different geographical and geological settings. SKBF/KBS technical report 83-03 contains the proceedings from the first workshop on these matters that was held at the State University of New York, Buffalo May 26-27, 1982. (Author).

1984-01-01

291

[Calling and mating behaviors of bamboo shoot borer Kumasia kumaso].  

Science.gov (United States)

The calling and mating behaviors of Kumasia kumaso were studied in laboratory at (25 1) degrees C and (60 +/- 10) % RH under a cycle 14 L:10 D photo period, and the EAG response of male K. kumaso to female K. kumaso sex gland extracts was also tested. The calling and mating behaviors of K. kumaso could only be observed in scotophase. The females began calling at the first scotophase following emergence, and the peak of calling occurred during the second scotophase and decreased thereafter. The calling of the females commenced 0-4 h after dark, reached the maximum between the 5th and the 7th hour of the scotophase, and terminated during the last 1-2.5 h of the scotophase. Moth age had significant effects on the calling patterns. With increasing moth age, the onset time of calling advanced gradually, and the mean number of calling bouts as well as the calling length per bout had a gradual increase from calling day 1 to day 4 but decreased on day 5. The peak time and terminated time of calling advanced with increasing moth age. The mating of K. kumaso adults initiated during the first scotophase and terminated till the 5th scotophase following emergence, and the peak of mating was observed during the second scotophase. The peak of mating was observed 5.5-7.0 h after dark, and advanced with increasing moth age. Moth age affected the mean onset time of mating and the copulation duration significantly. With increasing moth age, the mean onset time of mating advanced, and the copulation duration decreased. Sex ratio had significant effects on the mating behavior as well. Treatment 2 female:1 male showed a significantly higher mating percentage, but an earlier onset time of mating and shorter copulation duration, as compared with treatment 1 female:1 male. The results of EAG test indicated that the male adults showed a significant EAG response to the sex gland extracts of 2-day-old virgin females. PMID:23479886

Shu, Jin-Ping; Teng, Ying; Zhang, Ai-Liang; Zhang, Ya-Bo; Deng, Shun; Wang, Hao-Jie

2012-12-01

292

Effect of multiple mating on reproduction and longevity of the phytoseiid mite Neoseiulus californicus.  

UK PubMed Central (United Kingdom)

Females of some insects and mites that mate repeatedly (multiple-mated females) or that have limited food supply have a shortened life span, compared to females that are allowed to mate only once (single-mated females) or that have ample food. The present study focused on the relationship between mating frequency and various reproduction-related parameters in a commercial strain (Spical) of the phytoseiid mite Neoseiulus californicus (McGregor) (Acari: Phytoseiidae). The impetus for this study came from the previous finding that single-mated females displayed an extremely long postoviposition period (ca. 60 days), accounting for more than 75% of the total adult longevity. In the present study it was found that the postoviposition period in the multiple-mated females was shorter than in the single-mated females and that longevity was gradually shortened with increasing mating frequency. Total egg production in females that mated twice or more was higher than in single-mated females, but egg production did not increase further with more than two matings. Single- and multiple-mated females ceased oviposition on the 24th and 34th day of adult life, respectively; multiple-mated females produced only male progeny on and after the 30th day. The postoviposition period of multiple-mated females was 40% shorter than that of single-mated females. Yet, the postoviposition period of the multiple-mated females is still more than 30 days, suggesting that other factors besides mating frequency have an influence on the prolonged postoviposition period. The reproductive ability of the Spical strain females gradually decreased with increasing virgin period (i.e. with increasing age), but they did not lose their reproductive potential--not even when mating was delayed for more than 2 months (i.e. females remained virgin for 70 days).

Gotoh T; Tsuchiya A

2008-03-01

293

The role of calcium in the Chlamydomonas reinhardtii mating reaction.  

UK PubMed Central (United Kingdom)

The mating reaction of Chlamydomonas reinhardtii entails a rapid series of cell-cell interactions leading to cell fusion. We have demonstrated (Pasquale, S. M., and U. Goodenough. 1987. J. Cell Biol. 105:2279-2293) that cAMP plays a key role in this process: gametic flagellar adhesion elicits a sharp increase in intracellular cAMP, and presentation of dibutyryl-cAMP to unmated gametes elicits all known mating responses. The present study evaluates the role of Ca2+ in this system. We document that the mating-induced increase in cAMP, and hence the mating responses themselves, are blocked by a variety of drugs known to interfere with Ca(2+)-sensitive processes. These data suggest that Ca(2+)-mediated events may couple adhesion to the generation of cAMP. Such events, however, appear to be localized to the flagellar membrane; we find no evidence for the mating-related increase in cytosolic free Ca2+ that has been postulated by others. Indeed, by monitoring the length of the Ca(2+)-sensitive centrin-containing nucleus-basal body connector, we show that cytosolic free Ca2+ levels, if anything, decrease in response to cAMP signaling. We confirm a previous report that Ca2+ levels increase in the mating medium, but document that this represents a response to augmented cAMP levels and not a prelude. Finally, we show that IP3 levels remain constant throughout the mating reaction. These results are discussed in terms of the various signal transduction systems that have now been identified in Chlamydomonas.

Goodenough UW; Shames B; Small L; Saito T; Crain RC; Sanders MA; Salisbury JL

1993-04-01

294

Female lizards ignore the sweet scent of success: Male characteristics implicated in female mate preference.  

UK PubMed Central (United Kingdom)

Sexual selection molds the morphology, physiology and behavior of males in many animals. At first glance, it seems reasonable to assume that females would use the same male traits and signals in mate choice as males do during male-male competition. However, intra- and intersexual competition may affect traits in the same or the opposite direction, with differing strength. We investigated which color, morphometric and performance traits are selected for through male-male competition and whether female mate preference is based on these same traits and/or dominance status in the three male color morphs of the lizard Podarcis melisellensis. Males with relatively bigger heads and relatively higher bite forces were more likely to win fights and orange males were always dominant over the other morphs. Females, however, preferred scents of bigger males that were in better body condition, and surprisingly had lower bite force capacities. They did not show a preference for scents of any particular color morph or for scents of the more dominant males. These results indicate that intra- and intersexual competition may result in selection for different secondary sexual traits in P. melisellensis.

Huyghe K; Vanhooydonck B; Herrel A; Tadi? Z; Van Damme R

2012-08-01

295

Chemical characterization of candy made of Erva-Mate (Ilex paraguariensis A. St. Hil.) residue.  

UK PubMed Central (United Kingdom)

The aim of this work was to evaluate the chemical properties of the residues from erva-mate processing and also to determine the candy-making performance with addition of residues from erva-mate on consumers' acceptance and purchase intent of this new product. The candies containing different amounts of mate powder were evaluated through overall acceptability test and purchase intent. Mate powder showed high contents of dietary fiber, total ash, and total polyphenols. The total dietary fiber content of the mate candies ranged from 5.7 to 6.29% on a dry matter basis. Supplementation with mate powder caused significant increases in polyphenol and mineral contents of mate candies. The incorporation of mate powder increased the hardness of the candies and produced desirable results in their nutritional characteristics. The sensory tests indicated that mate candies were acceptable and approved in relation to purchase intent.

Vieira MA; Rovaris AA; Maraschin M; De Simas KN; Pagliosa CM; Podestá R; Amboni RD; Barreto PL; Amante ER

2008-06-01

296

Autoimmune status epilepticus.  

UK PubMed Central (United Kingdom)

OPINION STATEMENT: Autoimmune status epilepticus is a rare condition but one that has been increasingly recognized by neurologists and clinicians in the intensive care unit. As more cases are described in the literature and more antibody tests become commercially available, diagnosis is now feasible; however, early diagnosis remains a challenge. For practical purposes, status epilepticus may be considered as possibly autoimmune if it is refractory to anticonvulsant treatment and there is no other known cause; this may then lead to empiric immunomodulatory therapy. Major factors that raise the index of suspicion are recent cognitive or behavioral alterations, a history of malignancy or tumor, or presence of other neurological features. There is a lack of high level evidence in the literature for treatment of status epilepticus, and almost none for autoimmune encephalitis. Patients with autoimmune status epilepticus may be treated with immunomodulatory therapy, including steroids, intravenous immunoglobulin (IVIG), plasmapheresis (PLEX), and other immunosuppressive agents while maximizing their anticonvulsant therapy. For some patients, resective surgery may be necessary, such as hemispherectomy for Rasmussen's encephalopathy. In the case of status epilepticus due to paraneoplastic autoantibodies, urgent and aggressive testing and treatment of a primary malignancy is needed. Importantly, any suspicion of autoimmune mediated status epilepticus should prompt the transfer of the patient to a specialized center with experience in refractory status epilepticus whenever possible.

Lopinto-Khoury C; Sperling MR

2013-10-01

297

Marine Advanced Technology Education (MATE) Center  

Science.gov (United States)

National consortium of educational institutions and organizations seeking to improve marine technology education. The website has an overview of marine technology with current status and future development, information on careers and educational and professional development opportunities. Some curriculum material is provided with more coming soon. Learn how to make your very own ROV. Additional information on ROV contests, workshops, and cost-associated teacher resources are available.

298

Cancer and yerba mate consumption: a review of possible associations Cáncer y consumo de yerba mate: revisión de posibles asociaciones  

Directory of Open Access Journals (Sweden)

Full Text Available OBJECTIVE: To identify any possible link between mate consumption and cancer, mainly of the esophagus, larynx, and oral cavity. METHODS: A review of literature, published through August 2008, pertaining to the carcinogenic risk of mate consumption was undertaken by searching the two databases, MEDLINE and TOXLINE, for relevant articles. The bibliographies of the articles were examined for additional relevant sources. In addition, a search on the name of each author having published on the topic was conducted. The epidemiological studies are presented by cancer site; experimental works are examined in dedicated sections; and the discussion combines epidemiological and experimental evidence. RESULTS: Almost all epidemiological studies shared similar methodology: hospital-based, case-control studies where participants were personally interviewed on the main risk factors, using similar questionnaires. Several studies found an association between the temperature of the mate infusion and oral, esophageal, and/or laryngeal cancer risks; while a few focused on carcinogenic contaminants introduced during the industrial processing of the leaves. The cancer most frequently mentioned in association with hot mate with bombilla (drunk through a metal straw) was the esophagus. Size, exposure assessment, methods of analysis, and quality were different among the studies reviewed. The results varied greatly. The higher risk estimate (odds ratio = 34.6) was found for women who drank 1 L or more daily; for men it was only 4.8. Risk increased with duration, daily quantity, and temperature at drinking. The synergic action between mate, alcohol, and tobacco was a clear result in several studies, and in some, nutritional deficiencies and poor oral hygiene played a role. No increased risk was associated with cold mate beverages. CONCLUSIONS: The role of hot mate in increasing the risk of cancer of esophagus, larynx, and oral cavity seems to be supported by several epidemiological studies. The temperature could act by damaging the mucosa or accelerating metabolic reactions, including those with carcinogenic substances in tobacco and alcohol. However, there is no sound population-based casecontrol study on mate consumption as a risk factor for cancer. This, coupled with the range of results on mate risk, make assessing the etiological fraction difficult. More research needs to be done before a definitive statement can be made regarding cancer risk associated with any of the various forms of mate consumption. Future research should include population-based studies; collection of data on consumption of tobacco, alcohol, hot drinks, fresh fruit, and vegetables; and, a method to precisely measure volume and temperature of mate intake.OBJETIVO: Identificar posibles vínculos entre el consumo de mate y el cáncer, en particular de esófago, laringe y cavidad bucal. MÉTODOS: Se realizó una revisión de la bibliografía publicada hasta agosto de 2008 sobre el riesgo carcinogénico del consumo de mate en dos bases de datos, MEDLINE y TOXLINE. Se revisaron las referencias bibliográficas de los artículos para encontrar fuentes adicionales y se buscó por cada autor que hubiera publicado sobre el tema. Los estudios epidemiológicos se presentan según la localización del cáncer, los trabajos experimentales se examinan en secciones separadas y en la discusión se combinaron los datos epidemiológicos y experimentales. RESULTADOS: Casi todos los estudios epidemiológicos siguieron la misma metodología: estudios de casos y controles basados en hospitales donde se entrevistaba personalmente a los participantes acerca de los principales factores de riesgo mediante cuestionarios similares. En algunos estudios se encontró una asociación entre la temperatura de la infusión de mate y el riesgo de cáncer bucal, de esófago y de laringe, mientras que unos pocos se concentraron en los contaminantes carcinogénicos introducidos durante el procesamiento industrial de las hojas. El tipo de cáncer más frecuentemente mencionado en asociación

Dora Loria; Enrique Barrios; Roberto Zanetti

2009-01-01

299

Anticonvulsant, neuroprotective and behavioral effects of organic and conventional yerba mate (Ilex paraguariensis St. Hil.) on pentylenetetrazol-induced seizures in Wistar rats.  

Science.gov (United States)

Epilepsy, which is one of the most common neurological disorders, involves the occurrence of spontaneous and recurrent seizures that alter the performance of the brain and affect several sensory and behavioral functions. Oxidative damage has been associated with post-seizure neuronal injury, thereby increasing an individual's susceptibility to the occurrence of neurodegenerative disorders. The present study investigated the possible anticonvulsive and neuroprotective effects of organic and conventional yerba mate (Ilex paraguariensis), a plant rich in polyphenols, on pentylenetetrazol (PTZ)-induced seizures in Wistar rats. The behavioral and polyphenolic profiles of the yerba mate samples were also evaluated. Infusions of yerba mate (50mg/kg) or distilled water were given to rats for fifteen days by oral gavage. On the 15th day the animals were subjected to open field test, and exploratory behavior was assessed. Subsequently, 60mg/kg PTZ (i.p.) was administered, and animals were observed for the appearance of convulsions for 30min. Latency for the first seizure, tonic-clonic and generalized seizures time, frequency of seizures and mortality induced by PTZ were recorded. The animals were then sacrificed, and the cerebellum, cerebral cortex and hippocampus were quickly removed and frozen to study the neuroprotective effects of yerba mate. The oxidative damage in lipids and proteins, nitric oxide levels, the activities of the antioxidant enzymes superoxide dismutase (Sod) and catalase (Cat) and non-enzymatic cellular defense (sulfhydryl protein) were quantified in all the tissues. The results showed that organic and conventional yerba mate infusions were able to reduce the frequency of seizures when compared to the PTZ group. Besides, organic yerba mate infusion decreases the tonic-clonic seizures time in relation to the PTZ group. It was also shown that organic and conventional yerba mate infusions reduced the oxidative damage in lipids and proteins and nitric oxide levels and prevented the decrease in Sod and Cat activities and sulfhydryl protein content when compared to the PTZ group in all the CNS tissues assayed. Organic and conventional yerba mate commercial samples did not change the behavior (locomotion, exploration or anxiety) of the treated animals. In both organic and conventional infusions, the presence of the polyphenols rutin, chlorogenic acid and their acyl derivatives were detected, which could be associated with the biological effects observed. These data indicate that yerba mate may provide new perspectives for the development of therapeutic approaches with natural compounds in the pharmaceutical area, both to reduce the convulsions' frequency and to minimize the neuronal damage associated with recurrent seizures. PMID:23270878

Branco, Cátia Dos Santos; Scola, Gustavo; Rodrigues, Adriana Dalpicolli; Cesio, Verónica; Laprovitera, Mariajosé; Heinzen, Horacio; Dos Santos, Maitê Telles; Fank, Bruna; de Freitas, Suzana Cesa Vieira; Coitinho, Adriana Simon; Salvador, Mirian

2012-12-24

300

Anticonvulsant, neuroprotective and behavioral effects of organic and conventional yerba mate (Ilex paraguariensis St. Hil.) on pentylenetetrazol-induced seizures in Wistar rats.  

UK PubMed Central (United Kingdom)

Epilepsy, which is one of the most common neurological disorders, involves the occurrence of spontaneous and recurrent seizures that alter the performance of the brain and affect several sensory and behavioral functions. Oxidative damage has been associated with post-seizure neuronal injury, thereby increasing an individual's susceptibility to the occurrence of neurodegenerative disorders. The present study investigated the possible anticonvulsive and neuroprotective effects of organic and conventional yerba mate (Ilex paraguariensis), a plant rich in polyphenols, on pentylenetetrazol (PTZ)-induced seizures in Wistar rats. The behavioral and polyphenolic profiles of the yerba mate samples were also evaluated. Infusions of yerba mate (50mg/kg) or distilled water were given to rats for fifteen days by oral gavage. On the 15th day the animals were subjected to open field test, and exploratory behavior was assessed. Subsequently, 60mg/kg PTZ (i.p.) was administered, and animals were observed for the appearance of convulsions for 30min. Latency for the first seizure, tonic-clonic and generalized seizures time, frequency of seizures and mortality induced by PTZ were recorded. The animals were then sacrificed, and the cerebellum, cerebral cortex and hippocampus were quickly removed and frozen to study the neuroprotective effects of yerba mate. The oxidative damage in lipids and proteins, nitric oxide levels, the activities of the antioxidant enzymes superoxide dismutase (Sod) and catalase (Cat) and non-enzymatic cellular defense (sulfhydryl protein) were quantified in all the tissues. The results showed that organic and conventional yerba mate infusions were able to reduce the frequency of seizures when compared to the PTZ group. Besides, organic yerba mate infusion decreases the tonic-clonic seizures time in relation to the PTZ group. It was also shown that organic and conventional yerba mate infusions reduced the oxidative damage in lipids and proteins and nitric oxide levels and prevented the decrease in Sod and Cat activities and sulfhydryl protein content when compared to the PTZ group in all the CNS tissues assayed. Organic and conventional yerba mate commercial samples did not change the behavior (locomotion, exploration or anxiety) of the treated animals. In both organic and conventional infusions, the presence of the polyphenols rutin, chlorogenic acid and their acyl derivatives were detected, which could be associated with the biological effects observed. These data indicate that yerba mate may provide new perspectives for the development of therapeutic approaches with natural compounds in the pharmaceutical area, both to reduce the convulsions' frequency and to minimize the neuronal damage associated with recurrent seizures.

Branco Cdos S; Scola G; Rodrigues AD; Cesio V; Laprovitera M; Heinzen H; Dos Santos MT; Fank B; de Freitas SC; Coitinho AS; Salvador M

2013-03-01

 
 
 
 
301

Aggregation and mating success of Capnodis tenebrionis (Coleoptera: Buprestidae).  

UK PubMed Central (United Kingdom)

An understanding of the relative importance of extrinsic and intrinsic factors in determining the potential distribution and mating success of individuals is critical for the successful monitoring and management of pest species. Using a combination of field observations and a caged field experiment, we explored the roles of environmental and individual variation on the formation of mating aggregations and mating success in the buprestid beetle Capnodis tenebrionis (Linnaeus, 1767), a pest species of stone fruit trees. Our field observations revealed that the formation of aggregations is influenced by a range of environmental factors including temperature, photoperiod, and population density. However, aggregations were not at random and were more likely to occur on the section of the plant with highest incidence of solar radiation and thus higher temperatures. Data from our experiment with caged beetles in the field further indicate that the reproductive behavior of this species varies with temperature. The probability of a successful mating occurring was also positively related to both male and female size. Females of C. tenebrionis mate several times over a 4-h period, but generally not with the same male. Information obtained from these studies is useful to define the most appropriate time for pest control, especially adopting strategies that interfere with reproduction.

Bonsignore CP; Jones TM

2013-04-01

302

Role of the iridescent eye in stickleback female mate choice.  

Science.gov (United States)

Many vertebrates exhibit prominent body colours that are used in courtship and territorial communication. Some fishes also have an eye whose iris becomes iridescent during the mating season, as in the threespine stickleback. Behavioural studies in this species have focused on the redness of the throat/jaw as the primary determinant of female mate choice. Unlike the iridescent eye, however, the red throat/jaw is not present in all stickleback populations, suggesting that the colour of the eye may be equally important for female mate choice. Here, we used data on photoreceptors and environmental light to assess body conspicuousness and the colour contrast of courtship signals for stickleback populations living in a range of waters, from clear (mesotrophic) to red light shifted (dystrophic). This analysis indicated that the redness of the throat/jaw is expressed to enhance the contrast of the eye. To test the importance of eye colour as a courtship signal, we carried out mate choice experiments in which females were presented with identical videos of a courting male but for the colour of the eye and/or the throat/jaw. Females did not choose based on differences in throat/jaw redness between videos, but preferred males with the highest contrast between the eye and the throat/jaw. This result points to the blue iridescent eye as a primary courtship signal in stickleback female mate choice. PMID:23580716

Flamarique, Iñigo Novales; Bergstrom, Carolyn; Cheng, Christiana L; Reimchen, Thomas E

2013-04-11

303

Role of the iridescent eye in stickleback female mate choice.  

UK PubMed Central (United Kingdom)

Many vertebrates exhibit prominent body colours that are used in courtship and territorial communication. Some fishes also have an eye whose iris becomes iridescent during the mating season, as in the threespine stickleback. Behavioural studies in this species have focused on the redness of the throat/jaw as the primary determinant of female mate choice. Unlike the iridescent eye, however, the red throat/jaw is not present in all stickleback populations, suggesting that the colour of the eye may be equally important for female mate choice. Here, we used data on photoreceptors and environmental light to assess body conspicuousness and the colour contrast of courtship signals for stickleback populations living in a range of waters, from clear (mesotrophic) to red light shifted (dystrophic). This analysis indicated that the redness of the throat/jaw is expressed to enhance the contrast of the eye. To test the importance of eye colour as a courtship signal, we carried out mate choice experiments in which females were presented with identical videos of a courting male but for the colour of the eye and/or the throat/jaw. Females did not choose based on differences in throat/jaw redness between videos, but preferred males with the highest contrast between the eye and the throat/jaw. This result points to the blue iridescent eye as a primary courtship signal in stickleback female mate choice.

Flamarique IN; Bergstrom C; Cheng CL; Reimchen TE

2013-08-01

304

Glomerella truncata: another Glomerella species with an atypical mating system.  

UK PubMed Central (United Kingdom)

In the genus Glomerella all species studied to date do not fit the usual mating system of heterothallic ascomycetes. This study investigated the mating system of G. truncata (anamorph Colletotrichum truncatum), a pathogen responsible for lentil anthracnose. Twenty-two field isolates from the Canadian prairies were crossed in all possible combinations, including selfings. All isolates also were screened for the presence of the MAT1-1 and MAT1-2 idiomorphs by targeting small conserved areas of the MAT genes (the alpha domain and the high mobility group HMG box) with degenerate primers, and a pair of G. truncata-specific HMG primers (CT21HMG) were designed. The results of the classical mating study suggested that G. truncata is heterothallic. Isolates fell into two incompatibility groups, which is consistent with a bipolar mating system but different from what has been described in other Glomerella species. Molecular screening showed that the HMG box used as a marker for the MAT1-2 idiomorph was present in both partners of fertile crosses in G. truncata, unlike in the typical ascomycete system, but as previously described for two other Glomerella species. G. truncata therefore appears to share unusual mating system characteristics with the other Glomerella species studied to date.

Menat J; Cabral AL; Vijayan P; Wei Y; Banniza S

2012-05-01

305

Genetic analysis of mate discrimination in Drosophila simulans.  

UK PubMed Central (United Kingdom)

Courtship is an elaborate behavior that conveys information about the identity of animal species and suitability of individual males as mates. In Drosophila, there is extensive evidence that females are capable of evaluating and comparing male courtships, and accepting or rejecting males as mates. These relatively simple responses minimize random sexual encounters involving subpar conspecific males and heterospecific males, and over generations can potentially select novel physical and behavioral traits. Despite its evolutionary and behavioral significance, little is still known about the genes involved in mating choice and how choices for novel males and females arise during evolution. Drosophila simulans and Drosophila sechellia are two recently diverged species of Drosophila in which females have a preference for conspecific males. Here we analyzed a total of 1748 F2 hybrid females between these two species and found a small number of dominant genes controlling the preference for D. simulans males. We also mapped two redundant X-linked loci of mating choice, Macho-XA and Macho-XB, and show that neither one is required for female attractiveness. Together, our results reveal part of the genetic architecture that allows D. simulans females to recognize, mate, and successfully generate progenies with D. simulans males.

Chu Y; Yang E; Schinaman JM; Chahda JS; Sousa-Neves R

2013-08-01

306

The role of male contest competition over mates in speciation  

Directory of Open Access Journals (Sweden)

Full Text Available Research on the role of sexual selection in the speciation process largely focuses on the diversifying role of mate choice. In particular, much attention has been drawn to the fact that population divergence in mate choice and in the male traits subject to choice directly can lead to assortative mating. However, male contest competition over mates also constitutes an important mechanism of sexual selection. We review recent empirical studies and argue that sexual selection through male contest competition can affect speciation in ways other than mate choice. For example, biases in aggression towards similar competitors can lead to disruptive and negative frequency-dependent selection on the traits used in contest competition in a similar way as competition for other types of limited resources. Moreover, male contest abilities often trade-off against other abilities such as parasite resistance, protection against predators and general stress tolerance. Populations experiencing different ecological conditions should therefore quickly diverge non-randomly in a number of traits including male contest abilities. In resource based breeding systems, a feedback loop between competitive ability and habitat use may lead to further population divergence. We discuss how population divergence in traits used in male contest competition can lead to the build up of reproductive isolation through a number of different pathways. Our main conclusion is that the role of male contest competition in speciation remains largely scientifically unexplored [Current Zoology 58 (3): 490–506, 2012].

Anna QVARNSTRÖM, Niclas VALLIN, Andreas RUDH

2012-01-01

307

Genetic variation in social influence on mate preferences.  

UK PubMed Central (United Kingdom)

Patterns of phenotypic variation arise in part from plasticity owing to social interactions, and these patterns contribute, in turn, to the form of selection that shapes the variation we observe in natural populations. This proximate-ultimate dynamic brings genetic variation in social environments to the forefront of evolutionary theory. However, the extent of this variation remains largely unknown. Here, we use a member of the Enchenopa binotata species complex of treehoppers (Hemiptera: Membracidae) to assess how mate preferences are influenced by genetic variation in the social environment. We used full-sibling split-families as 'treatment' social environments, and reared focal females alongside each treatment family, describing the mate preferences of the focal females. With this method, we detected substantial genetic variation in social influence on mate preferences. The mate preferences of focal females varied according to the treatment families along with which they grew up. We discuss the evolutionary implications of the presence of such genetic variation in social influence on mate preferences, including potential contributions to the maintenance of genetic variation, the promotion of divergence, and the adaptive evolution of social effects on fitness-related traits.

Rebar D; Rodríguez RL

2013-07-01

308

Floral to green: mating switches moth olfactory coding and preference.  

UK PubMed Central (United Kingdom)

Mating induces profound physiological changes in a wide range of insects, leading to behavioural adjustments to match the internal state of the animal. Here, we show for the first time, to our knowledge, that a noctuid moth switches its olfactory response from food to egg-laying cues following mating. Unmated females of the cotton leafworm (Spodoptera littoralis) are strongly attracted to lilac flowers (Syringa vulgaris). After mating, attraction to floral odour is abolished and the females fly instead to green-leaf odour of the larval host plant cotton, Gossypium hirsutum. This behavioural switch is owing to a marked change in the olfactory representation of floral and green odours in the primary olfactory centre, the antennal lobe (AL). Calcium imaging, using authentic and synthetic odours, shows that the ensemble of AL glomeruli dedicated to either lilac or cotton odour is selectively up- and downregulated in response to mating. A clear-cut behavioural modulation as a function of mating is a useful substrate for studies of the neural mechanisms underlying behavioural decisions. Modulation of odour-driven behaviour through concerted regulation of odour maps contributes to our understanding of state-dependent choice and host shifts in insect herbivores.

Saveer AM; Kromann SH; Birgersson G; Bengtsson M; Lindblom T; Balkenius A; Hansson BS; Witzgall P; Becher PG; Ignell R

2012-06-01

309

The Study and Analysis of the Mating Behavior and Sound Production of Male Cicada Psalmocharias alhageos (Kol.) (Homoptera:Cicadidae) to Make Disruption in Mating  

Directory of Open Access Journals (Sweden)

Full Text Available Psalmocharias alhageos is an important pest of vine in most parts of Iran, Afghanistan, Pakistan, southern areas of Russia, Turkey and Iraq. This cicada is spread in most provinces in Iran such as Esfahan, Hamedan, Qazvin, Markazi, Lorestan, Qom, Kerman, Tehran and Kordestan. In addition to vine, this insect damages some other fruit trees, such as apple, sour cherry, quince, peach, pomegranate and pear trees and some non-fruit trees, namely white poplar, ash, elm, eglantine, silk and black poplar trees. The nymphs of cicada damage the trees by feeding on root, adult insects on young bud and by oviposition under branch barks. Nourishing root by nymph leads to the weakness of the tree and hinder its growth. The high density oviposition of adult insects inside young barks causes withering of branches. The resulted damage on vine products is 40% which is one of the most important factors in product reduction in vineyard. This research was conducted in Takestan in Qazvin. It was conducted for the first time to study the behaviors of the mates of this vine cicada in order to manage it. Two systems were used to record the sound of male cicada called analog voice-recorder and digital voice recorder. To analyze the recorded sound of the male cicada we used of spectrum analyzer, digital storage oscilloscope and protens 7 computer softwares. We could call the attention of natural enemies an disturb the male insect`s attracting sound by producing natural and artificial sound in the range of 1-6 kHz in two different ripeness status of the fruits and could prevent mating and oviposition of female cicadas.

H. Zamanian; M. Mehdipour; N. Ghaemi

2008-01-01

310

Cancer and yerba mate consumption: a review of possible associations/ Cáncer y consumo de yerba mate: revisión de posibles asociaciones  

Scientific Electronic Library Online (English)

Full Text Available Abstract in spanish OBJETIVO: Identificar posibles vínculos entre el consumo de mate y el cáncer, en particular de esófago, laringe y cavidad bucal. MÉTODOS: Se realizó una revisión de la bibliografía publicada hasta agosto de 2008 sobre el riesgo carcinogénico del consumo de mate en dos bases de datos, MEDLINE y TOXLINE. Se revisaron las referencias bibliográficas de los artículos para encontrar fuentes adicionales y se buscó por cada autor que hubiera publicado sobre el tema. Lo (more) s estudios epidemiológicos se presentan según la localización del cáncer, los trabajos experimentales se examinan en secciones separadas y en la discusión se combinaron los datos epidemiológicos y experimentales. RESULTADOS: Casi todos los estudios epidemiológicos siguieron la misma metodología: estudios de casos y controles basados en hospitales donde se entrevistaba personalmente a los participantes acerca de los principales factores de riesgo mediante cuestionarios similares. En algunos estudios se encontró una asociación entre la temperatura de la infusión de mate y el riesgo de cáncer bucal, de esófago y de laringe, mientras que unos pocos se concentraron en los contaminantes carcinogénicos introducidos durante el procesamiento industrial de las hojas. El tipo de cáncer más frecuentemente mencionado en asociación con el mate caliente en bombilla (tomado a través de una cañita metálica) fue el de esófago. El tamaño de la muestra, la evaluación de la exposición, el método de análisis y la calidad variaron de un estudio a otro. Los resultados variaron considerablemente. Se estimó un mayor riesgo (razón de posibilidades = 34,6) en las mujeres que tomaban 1 L diario o más; en los hombres este riesgo fue solo de 4,8. El riesgo aumentó con el tiempo de consumo, la cantidad diaria y la temperatura de la infusión consumida. En algunos estudios se observó una clara sinergia entre el consumo de mate, alcohol y tabaco, mientras que en otros las deficiencias nutricionales y la inadecuada higiene bucal desempeñaron un papel importante. No se observó aumento en el riesgo asociado con el consumo de bebidas frías de mate. CONCLUSIONES: Varios estudios epidemiológicos parecen respaldar el papel de las bebidas calientes de mate en el aumento del riesgo de cáncer de esófago, laringe y cavidad bucal. La temperatura podría influir al dañar la mucosa o acelerar algunas reacciones metabólicas, entre ellas con algunas sustancias carcinogénicas del tabaco y el alcohol. No obstante, no se encontraron estudios robustos de casos y controles basados en la población sobre el consumo de mate como factor de riesgo de cáncer. Esto, unido a los resultados encontrados sobre el riesgo del consumo de mate, hace difícil estimar su fracción etiológica. Se requieren más investigaciones antes de establecer definitivamente el riesgo de cáncer asociado con alguna de las diversas formas de consumo de mate. Se deben realizar estudios basados en la población, obtener más datos sobre el consumo de tabaco, alcohol, bebidas calientes, frutas frescas y vegetales y se deben emplear métodos que permitan medir con precisión el volumen y la temperatura del mate consumido. Abstract in english OBJECTIVE: To identify any possible link between mate consumption and cancer, mainly of the esophagus, larynx, and oral cavity. METHODS: A review of literature, published through August 2008, pertaining to the carcinogenic risk of mate consumption was undertaken by searching the two databases, MEDLINE and TOXLINE, for relevant articles. The bibliographies of the articles were examined for additional relevant sources. In addition, a search on the name of each author having (more) published on the topic was conducted. The epidemiological studies are presented by cancer site; experimental works are examined in dedicated sections; and the discussion combines epidemiological and experimental evidence. RESULTS: Almost all epidemiological studies shared similar methodology: hospital-based, case-control studies where partici

Loria, Dora; Barrios, Enrique; Zanetti, Roberto

2009-06-01

311

Mating disruption for the control of Aonidiella aurantii Maskell (Hemiptera: Diaspididae) may contribute to increased effectiveness of natural enemies.  

UK PubMed Central (United Kingdom)

BACKGROUND: New directives on sustainable use of pesticides have encouraged research on efficient alternative pest control methods. In the case of the California red scale (CRS), Aonidiella aurantii (Maskell), this imperative, along with the many difficulties in controlling this pest, have led to the investigation of new approaches. Previously developed mating disruption (MD) dispensers, together with the augmentative releases of the parasitoid Aphytis melinus DeBach, are here considered as a combined strategy for use against A. aurantii. RESULTS: Efficacy of MD was demonstrated by a mean reduction of 80% in CRS male catches and a mean fruit damage reduction of 83% compared with the control. A delay in the development of A. aurantii instars was observed in the MD plot. This delay increased the period of exposure of the susceptible instars to natural enemies, which resulted in higher predation and parasitism levels in the MD plot. Under laboratory conditions, A. melinus mating behaviour and effects on A. aurantii were not significantly altered in a CRS-pheromone-saturated environment. CONCLUSION: Mating disruption pheromone did not affect the behaviour or level of parasitism by A. melinus or the incidence of other generalist predators. Therefore, A. aurantii pheromone appears to be compatible with augmentative releases and biological control, making its use a good strategy for CRS management.

Vacas S; Vanaclocha P; Alfaro C; Primo J; Verdú MJ; Urbaneja A; Navarro-Llopis V

2012-01-01

312

Temperature, age of mating and starvation determine the role of maternal effects on sex allocation in the mealybug Planococcus citri.  

UK PubMed Central (United Kingdom)

Environmental effects on sex allocation are common, yet the evolutionary significance of these effects remains poorly understood. Environmental effects might influence parents, such that their condition directly influences sex allocation by altering the relative benefits of producing sons versus daughters. Alternatively, the environment might influence the offspring themselves, such that the conditions they find themselves in influence their contribution to parental fitness. In both cases, parents might be selected to bias their sex ratio according to the prevailing environmental conditions. Here, we consider sex allocation in the citrus mealybug Planococcus citri, a species with an unusual genetic system in which paternal genes are lost from the germline in males. We test environmental factors that may influence either female condition directly (rearing temperature and food restriction) or that may be used as cues of the future environment (age at mating). Using cytological techniques to obtain primary sex ratios, we show that high temperature, older age at mating and starvation all affect sex allocation, resulting in female-biased sex ratios. However, the effect of temperature is rather weak, and food restriction appears to be strongly associated with reduced longevity and a truncation of the usual schedule of male and offspring production across a female's reproductive lifetime. Instead, facultative sex allocation seems most convincingly affected by age at mating, supporting previous work that suggests that social interactions experienced by adult P. citri females are used when allocating sex. Our results highlight that, even within one species, different aspects of the environment may have conflicting effects on sex allocation.

Ross L; Dealey EJ; Beukeboom LW; Shuker DM

2011-05-01

313

Mating activity of gamma irradiated codling moth, Laspeyresia pomonella (L.)  

International Nuclear Information System (INIS)

Mating of 30-krad treated codling moths, Laspeyresia pomonella, under field cage conditions occurred mainly at temperatures ranging from 14 to 200C. Irradiation applied to diet-reared moths produced neither an apparent shift in the time (hours) of copulation nor a decrease of the mating activity. However, a significant reduction in the mating ability was induced by Calco Oil Red added to the larval diet, and also by handling and transporting the moths about 140 km to the irradiation facilities. The morning time was found to be the best time to release irradiated moths in the field. Males reared on thinning apples were two times more active sexually than ones reared on an artificial medium. (author)

1979-01-01

314

Irradiation detection of coffee mate by electron spin resonance (ESR)  

International Nuclear Information System (INIS)

Un-irradiated coffee mate samples do not exhibit any ESR signal. However, the samples exposed to UV and gamma radiation exhibit an ESR singlet and a large unresolved ESR signal, respectively. The dose-response curves of the samples exposed to UV and gamma radiations were found to be described well by an exponential and linear functions, respectively. Variable temperature and fading studies at room temperature showed that the radiation-induced radicals in coffee mate sample are very sensitive to temperature. The discrimination between un-irradiated and irradiated coffee mate samples can be done just comparing their ESR spectra. However, determination of the radiation dose received by the sample cannot be possible because of the fast decay of signal intensity at room temperature.

2011-01-01

315

Irradiation detection of coffee mate by electron spin resonance (ESR)  

Energy Technology Data Exchange (ETDEWEB)

Un-irradiated coffee mate samples do not exhibit any ESR signal. However, the samples exposed to UV and gamma radiation exhibit an ESR singlet and a large unresolved ESR signal, respectively. The dose-response curves of the samples exposed to UV and gamma radiations were found to be described well by an exponential and linear functions, respectively. Variable temperature and fading studies at room temperature showed that the radiation-induced radicals in coffee mate sample are very sensitive to temperature. The discrimination between un-irradiated and irradiated coffee mate samples can be done just comparing their ESR spectra. However, determination of the radiation dose received by the sample cannot be possible because of the fast decay of signal intensity at room temperature.

Ozsayin, Fulya [Physics Engineering Department, Hacettepe University, 06800 Ankara (Turkey); Polat, Mustafa, E-mail: polat@hacettepe.edu.t [Physics Engineering Department, Hacettepe University, 06800 Ankara (Turkey)

2011-06-15

316

Reduced proceptivity and sex-motivated behaviors in the female rat after repeated copulation in paced and non-paced mating: Effect of changing the male.  

UK PubMed Central (United Kingdom)

The mating inhibition after repeated copulation (sexual satiety) and its re-commencement after changing the sexually active partner (Coolidge effect) are well recognized phenomena in males, but their occurrence in females is little explored. These two phenomena were compared in conditions when the female regulates copulation timing (pacing) and under non-paced mating. Female rats selected in proestrus copulated incessantly for 3h with two different partners (for 90min each), both of them sexually active and unknown for the female. During the entire test we recorded the hop/dart and ear wiggling frequencies and the lordosis quotient. In the pacing test we also registered the percentage of exits and the return latencies after mounts, intromissions and ejaculation within each copulatory series, the mean time the female spent in the neutral chamber and the number of crossings. In the non-paced mating situation there was a reduction in ear wiggling and hop/darting frequencies after 3h of constant copulation. In the paced mating condition, also by the end of the test, the female spent more time in the neutral compartment and showed fewer crossings to the male's zone. Only when the female regulated mating, the change of the male provoked an increased hop/darting frequency accompanied by a reduced percentage of exits from the male's chamber after an intromission and in the time in the neutral compartment. These changes were not associated with alterations in receptivity, which was maximal along the test. Data are discussed by comparing the mating conditions and the sex differences in the effect of repeated copulation and partner replacement.

Ventura-Aquino E; Fernández-Guasti A

2013-07-01

317

Lonely hearts or sex in the city? Density-dependent effects in mating systems.  

UK PubMed Central (United Kingdom)

Two very basic ideas in sexual selection are heavily influenced by numbers of potential mates: the evolution of anisogamy, leading to sex role differentiation, and the frequency dependence of reproductive success that tends to equalize primary sex ratios. However, being explicit about the numbers of potential mates is not typical to most evolutionary theory of sexual selection. Here, we argue that this may prevent us from finding the appropriate ecological equilibria that determine the evolutionary endpoints of selection. We review both theoretical and empirical advances on how population density may influence aspects of mating systems such as intrasexual competition, female choice or resistance, and parental care. Density can have strong effects on selective pressures, whether or not there is phenotypic plasticity in individual strategies with respect to density. Mating skew may either increase or decrease with density, which may be aided or counteracted by changes in female behaviour. Switchpoints between alternative mating strategies can be density dependent, and mate encounter rates may influence mate choice (including mutual mate choice), multiple mating, female resistance to male mating attempts, mate searching, mate guarding, parental care, and the probability of divorce. Considering density-dependent selection may be essential for understanding how populations can persist at all despite sexual conflict, but simple models seem to fail to predict the diversity of observed responses in nature. This highlights the importance of considering the interaction between mating systems and population dynamics, and we strongly encourage further work in this area.

Kokko H; Rankin DJ

2006-02-01

318

Mate choice for genetic compatibility in the house mouse.  

UK PubMed Central (United Kingdom)

In house mice, genetic compatibility is influenced by the t haplotype, a driving selfish genetic element with a recessive lethal allele, imposing fundamental costs on mate choice decisions. Here, we evaluate the cost of genetic incompatibility and its implication for mate choice in a wild house mice population. In laboratory reared mice, we detected no fertility (number of embryos) or fecundity (ability to conceive) costs of the t, and yet we found a high cost of genetic incompatibility: heterozygote crosses produced 40% smaller birth litter sizes because of prenatal mortality. Surprisingly, transmission of t in crosses using +/t males was influenced by female genotype, consistent with postcopulatory female choice for + sperm in +/t females. Analysis of paternity patterns in a wild population of house mice showed that +/t females were more likely than +/+ females to have offspring sired by +/+ males, and unlike +/+ females, paternity of their offspring was not influenced by +/t male frequency, further supporting mate choice for genetic compatibility. As the major histocompatibility complex (MHC) is physically linked to the t, we investigated whether females could potentially use variation at the MHC to identify male genotype at the sperm or individual level. A unique MHC haplotype is linked to the t haplotype. This MHC haplotype could allow the recognition of t and enable pre- and postcopulatory mate choice for genetic compatibility. Alternatively, the MHC itself could be the target of mate choice for genetic compatibility. We predict that mate choice for genetic compatibility will be difficult to find in many systems, as only weak fertilization biases were found despite an exceptionally high cost of genetic incompatibility.

Lindholm AK; Musolf K; Weidt A; König B

2013-05-01

319

OCT2 and MATE1 provide bidirectional agmatine transport.  

UK PubMed Central (United Kingdom)

Agmatine is a biogenic amine (l-arginine metabolite) of potential relevance to several central nervous system (CNS) conditions. The identities of transporters underlying agmatine and polyamine disposition in mammalian systems are not well-defined. The SLC-family organic cation transporters (OCT) OCT1 and OCT2 and multidrug and toxin extrusion transporter-1 (MATE1) are transport systems that may be of importance for the cellular disposition of agmatine and putrescine. We investigated the transport of [(3)H]agmatine and [(3)H]putrescine in human embryonic kidney (HEK293) cells stably transfected with hOCT1, hOCT2, and hMATE1. Agmatine transport by hOCT1 and hOCT2 was concentration-dependent, whereas only hOCT2 demonstrated pH-dependent transport. hOCT2 exhibited a greater affinity for agmatine (K(m) = 1.84 ± 0.38 mM) than did hOCT1 (K(m) = 18.73 ± 4.86 mM). Putrescine accumulation was pH- and concentration-dependent in hOCT2-HEK cells (K(m) = 11.29 ± 4.26 mM) but not hOCT1-HEK cells. Agmatine accumulation, in contrast to putrescine, was significantly enhanced by hMATE1 overexpression, and was saturable (K(m) = 240 ± 31 ?M; V(max) = 192 ± 10 pmol/min/mg of protein). Intracellular agmatine was also trans-stimulated (effluxed) from hMATE1-HEK cells in the presence of an inward proton-gradient. The hMATE1-mediated transport of agmatine was inhibited by polyamines, the prototypical substrates MPP+ and paraquat, as well as guanidine and arcaine, but not l-arginine. These results suggest that agmatine disposition may be influenced by hOCT2 and hMATE1, two transporters critical in the renal elimination of xenobiotic compounds.

Winter TN; Elmquist WF; Fairbanks CA

2011-02-01

320

Regulation of glycoprotein synthesis in yeast by mating pheromones  

International Nuclear Information System (INIS)

In Saccharomyces cerevisiae, glycosylated proteins amount to less than 2% of the cell protein. Two intensively studied examples of yeast glycoproteins are the external cell wall - associated invertase and the vacuolar carboxypeptidase Y. Recently, it was shown that the mating pheromone, alpha factor, specifically and strongly inhibits the synthesis of N-glycosylated proteins in haploid a cells, whereas O-glycosylated proteins are not affected. In this paper, the pathways of glycoprotein biosynthesis are summarized briefly, and evidence is presented that mating pheomones have a regulatory function in glycoprotein synthesis

1984-01-01

 
 
 
 
321

[Mineral elements in mate herb (Ilex paraguariensis St. H.)  

UK PubMed Central (United Kingdom)

The importance of the research works on mate rests on the fact that this is greatly consumed in many South American countries. Our interest in this subject has increased because, in Europe, it use as an infusion seems to be increasing. The Na, K, Ca, Mg, Cu, Fe, Mn and Zn contents were determined by atomic absorption spectrometry techniques. Prior to this, samples were incinerated and dissolved in an acid mixture (HCl/HNO3). Results apparently show a high content of mineral elements, especially K. Mg and Mn, in mate, findings which we consider to be of great relevance.

Tenorio Sanz MD; Torija Isasa ME

1991-09-01

322

Occurrence of polycyclic aromatic hydrocarbons throughout the processing stages of erva-mate (Ilex paraguariensis).  

UK PubMed Central (United Kingdom)

The presence of polycyclic aromatic hydrocarbons (PAHs) in mate (Ilex paraguariensis) is believed to be due to the degradation of mate compounds and the burning of wood during the "sapeco" (rapid drying process) and the final drying steps, which are the most important processing stages in mate production. Due to the high toxicity of these compounds, studies on their presence in mate are extremely important. The aim of this study was to evaluate PAH levels in mate throughout the processing stages of its production. The PAHs were measured in samples collected at different stages of mate processing. Total PAHs content ranged widely (443-9001 microg/kg) in the samples, with the highest PAHs levels recorded during the mate drying step. The results indicate that the processing method currently used in mate production may lead to an increase in PAHs levels in the final product.

Vieira MA; Maraschin M; Rovaris AA; Amboni RD; Pagliosa CM; Xavier JJ; Amante ER

2010-06-01

323

Generation of diploid Pichia pastoris strains by mating and their application for recombinant protein production  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract Background Yeast mating provides an efficient means for strain and library construction. However, biotechnological applications of mating in the methylotrophic yeast Pichia pastoris have been hampered because of concerns about strain stability of P. pastoris

Chen Ming-Tang; Lin Song; Shandil Ishaan; Andrews Dewan; Stadheim Terrance A; Choi Byung-Kwon

324

Studies on the mating behaviour of radiosterilized males of potato tuberworm, Phthorimaea operculella (zeller)  

International Nuclear Information System (INIS)

Studies on the mating periodicity and propensity, ability and sperm competition of sterilized and unsterilized males of the potato tuberworm, Phthorimaea operculella (Zeller), were conducted under laboratory conditions. Results indicate that under the photoperiod of 14 h light and 10 h dark; both sterilized (45 Krad) and normal males mated only during scotophase. Following irradiation, there was delay in mating and normal mating behaviour was marginally reduced. When virgin females were individually caged with one each of normal and sterile male, competition for mating was in favour of normal males on the first day, but was comparable for both the males on the second day. Egg viability pattern of the females mated with sterile and normal males or vice versa indicated that sperm transferred during recent mating predominantly took precedence over those transferred during the earlier mating. (author). 20 refs., 4 tabs

1990-01-01

325

Using Dissortative Mating Genetic Algorithms to Track the Extrema of Dynamic Deceptive Functions  

CERN Document Server

Traditional Genetic Algorithms (GAs) mating schemes select individuals for crossover independently of their genotypic or phenotypic similarities. In Nature, this behaviour is known as random mating. However, non-random schemes - in which individuals mate according to their kinship or likeness - are more common in natural systems. Previous studies indicate that, when applied to GAs, negative assortative mating (a specific type of non-random mating, also known as dissortative mating) may improve their performance (on both speed and reliability) in a wide range of problems. Dissortative mating maintains the genetic diversity at a higher level during the run, and that fact is frequently observed as an explanation for dissortative GAs ability to escape local optima traps. Dynamic problems, due to their specificities, demand special care when tuning a GA, because diversity plays an even more crucial role than it does when tackling static ones. This paper investigates the behaviour of dissortative mating GAs, namely...

Fernandes, C M; Rosa, A C

2009-01-01

326

Polygamy in the Marsh Harrier, 'Circus aeruginosus': Individual Variation in Hunting Performance and Number of Mates.  

Science.gov (United States)

Polygamous relationships have long attracted the interest of evolutionary biologists concerned with mating systems and sexual selection. It becomes especially troublesome if one considers polygamy in raptorial birds, where the sex mating with several part...

W. Altenburg S. Daan J. Starkenburg M. Zijlstra

1982-01-01

327

Effects of temperature variation on male behavior and mating success in a montane beetle.  

UK PubMed Central (United Kingdom)

Locomotion and mating ability are crucial for male reproductive success yet are energetically costly and susceptible to physiological stress. In the Sierra willow beetle Chrysomela aeneicollis, male mating success depends on locating and mating with as many females as possible. Variation at the glycolytic enzyme locus phosphoglucose isomerase (Pgi) is concordant with a latitudinal temperature gradient in these populations, with Pgi-1 frequent in the cooler north, Pgi-4 in the warmer south, and alleles 1 and 4 in relatively equal frequency in areas intermediate in geography and climate. Beetles experience elevated air temperatures during a mating season that causes differential physiological stress among Pgi genotypes, and running speeds of individuals homozygous for Pgi-4 are more tolerant of repeated thermal stress than individuals possessing Pgi-1. Here the importance of running behavior for male mating activity was examined, and differential effects of thermal stress among Pgi genotypes on male mating activity were measured. In nature, males run more than females, and nearly half of males mate or fight for a mate after running. In the laboratory, mating activity was positively correlated with running speed, and repeated mating did not reduce running speed or subsequent mating activity. Males homozygous for Pgi-4 mated longer and more frequently after heat treatment than 1-1 and 1-4 males. All heat-treated males had lower mating frequencies and higher heat shock protein expression than control males; however, mating frequency of recovering 4-4 males increased throughout mating trials, while treated 1-1 and 1-4 males remained low. These results suggest that effects of stress on mating activity differ between Pgi genotypes, implying a critical role for energy metabolism in organisms' response to stressful temperatures.

Dick CA; Rank NE; McCarthy M; McWeeney S; Hollis D; Dahlhoff EP

2013-07-01

328

Effects of temperature variation on male behavior and mating success in a montane beetle.  

Science.gov (United States)

Locomotion and mating ability are crucial for male reproductive success yet are energetically costly and susceptible to physiological stress. In the Sierra willow beetle Chrysomela aeneicollis, male mating success depends on locating and mating with as many females as possible. Variation at the glycolytic enzyme locus phosphoglucose isomerase (Pgi) is concordant with a latitudinal temperature gradient in these populations, with Pgi-1 frequent in the cooler north, Pgi-4 in the warmer south, and alleles 1 and 4 in relatively equal frequency in areas intermediate in geography and climate. Beetles experience elevated air temperatures during a mating season that causes differential physiological stress among Pgi genotypes, and running speeds of individuals homozygous for Pgi-4 are more tolerant of repeated thermal stress than individuals possessing Pgi-1. Here the importance of running behavior for male mating activity was examined, and differential effects of thermal stress among Pgi genotypes on male mating activity were measured. In nature, males run more than females, and nearly half of males mate or fight for a mate after running. In the laboratory, mating activity was positively correlated with running speed, and repeated mating did not reduce running speed or subsequent mating activity. Males homozygous for Pgi-4 mated longer and more frequently after heat treatment than 1-1 and 1-4 males. All heat-treated males had lower mating frequencies and higher heat shock protein expression than control males; however, mating frequency of recovering 4-4 males increased throughout mating trials, while treated 1-1 and 1-4 males remained low. These results suggest that effects of stress on mating activity differ between Pgi genotypes, implying a critical role for energy metabolism in organisms' response to stressful temperatures. PMID:23799837

Dick, Cynthia A; Rank, Nathan E; McCarthy, Meagan; McWeeney, Stephen; Hollis, Daniel; Dahlhoff, Elizabeth P

2013-06-18

329

Determinants of male reproductive health disorders: the Men in Australia Telephone Survey (MATeS)  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background The relationship between reproductive health disorders and lifestyle factors in middle-aged and older men is not clear. The aim of this study is to describe lifestyle and biomedical associations as possible causes of erectile dysfunction (ED), prostate disease (PD), lower urinary tract symptoms (LUTS) and perceived symptoms of androgen deficiency (pAD) in a representative population of middle-aged and older men, using the Men in Australia Telephone Survey (MATeS). Methods A representative sample (n = 5990) of men aged 40+ years, stratified by age and State, was contacted by random selection of households, with an individual response rate of 78%. All men participated in a 20-minute computer-assisted telephone interview exploring general and reproductive health. Associations between male reproductive health disorders and lifestyle and biomedical factors were analysed using multivariate logistic regression (odds ratio [95% confidence interval]). Variables studied included age, body mass index, waist circumference, smoking, alcohol consumption, physical activity, co-morbid disease and medication use for hypertension, high cholesterol and symptoms of depression. Results Controlling for age and a range of lifestyle and co-morbid exposures, sedentary lifestyle and being underweight was associated with an increased likelihood of ED (1.4 [1.1-1.8]; 2.9 [1.5-5.8], respectively) and pAD (1.3 [1.1-1.7]; 2.7 [1.4-5.0], respectively. Diabetes and cardiovascular disease were both associated with ED, with hypertension strongly associated with LUTS and pAD. Current smoking (inverse association) and depressive symptomatology were the only variables independently associated with PD. All reproductive disorders showed consistent associations with depression (measured either by depressive symptomatology or medication use) in both age-adjusted and multivariate analyses. Conclusion A range of lifestyle factors, more often associated with chronic disease, were significantly associated with male reproductive health disorders. Education strategies directed to improving general health may also confer benefits to male reproductive health.

Holden Carol A; McLachlan Robert I; Pitts Marian; Cumming Robert; Wittert Gary; Ehsani Johnathon P; de Kretser David M; Handelsman David J

2010-01-01

330

Enraizamento de Miniestacas de Erva-Mate sob Diferentes Ambientes Mate Minicuttings Rooting under Different Environments  

Directory of Open Access Journals (Sweden)

Full Text Available Pouco se conhece a respeito da propagação vegetativa da erva-mate, principalmente em relação à miniestaquia e aos aspectos relacionados ao ambiente de enraizamento. O estudo objetivou avaliar o efeito do ambiente inicial de enraizamento sobre a sobrevivência, vigor da parte aérea e enraizamento de miniestacas da espécie. O delineamento experimental foi o inteiramente casualizado em arranjo fatorial (3x2), sendo três clones (A7, A21 e A35) e dois ambientes de enraizamento (casa-de-vegetação simples, sem controle de temperatura e umidade e casa-de-vegetação automatizada). A sobrevivência das miniestacas na saída das casas de enraizamento e na casa-de-sombra não foram influenciadas pelo ambiente testado, com variação de 51,8 % a 71,9 %. Os clones A7 e A21 não diferiram significativamente quanto ao enraizamento, com médias de 49,1 % e 46,4 %, respectivamente. Contudo, o clone A35 mostrou-se superior quando proveniente da casa-de-vegetação automatizada, com 62,5 % de enraizamento. A casa-de-vegetação automatizada favoreceu tanto o número de folhas quanto o número e comprimento das brotações emitidas. A miniestaquia de erva-mate pode ser considerada tecnicamente viável em ambos os ambientes de enraizamento testados, apresentando resultados semelhantes. There is little knowledge about the vegetative propagation of Ilex  paraguariensis, mainly in relation to the minicutting technique and  rooting environmental aspects. This study aimed to evaluate the initial  rooting environment in relation to the survival, shoot vigor and  minicuttings rooting of this species. The experiment was conducted in  a completely randomized design, under a factorial arrange (3x2), with  three clones (A7, A21 and A35) and two rooting environments (simple greenhouse - without control of temperature and humidity; and automatized greenhouse - with automatized control). The minicutting  survival in the exit of greenhouses and in the exit of shadow house  was not influenced by the tested environments, with 51.8 % to 71.9 %  of survival variation. The A7 and A21 clones did not present  significative difference in relation to rooting, with averages of 49.1 %  and 46.4 %, respectively. However, the A35 clone showed the best  development (62.5 % of rooting) when it was cultivated under  automatized greenhouse condition. The automatized greenhouse  favored not only the characteristics leaf and shoot numbers, but also  the shoot length. The minicutting technique for I. paraguariensis may  be considered viable in both evaluated rooting environments, which  presented similar results.

Gilvano Ebling Brondani; Marla Alessandra de Araujo; Ivar Wendling; Dagma Kratz

2010-01-01

331

The adoptive transfer of embryo-antigen tolerant T cells induces the materno--fetal immuno-tolerance of the abortion prone matings  

UK PubMed Central (United Kingdom)

To investigate the effect of adoptive transfer of the embryo-antigen tolerant T cells on the immuno-tolerant status of recipients to their paternal antigens and the pregnancy outcome of abortion prone matings with the CAB/K×\\DBA/2 matings recruited as the abortion-prone model , and the CBA/K×BALB/c matings as the successful pregnancy model. The pregnant CBA/J mice mated with DBA/2 mice were injected intraperitoneally with rate anti-mouse CD80 and CD86 monoclonal antibodies or rat isotype IgG at 4 days of gestation (time for implantation). Purified T cells were obtained from spleen of the pregnant CBA/J mice by using the magnetic beads at 9 days of gestationl and then injected intravenously into the pregnant CBA/J mice mated with DBA/2 male mice at 4 days of gestation. One way mixed lymphocyte reaction was used to evaluate the proliferative responses of the splenic immuno-competent cells of recipients to paternal splenocytes used as stimulator, and the IL-2 expression was assayed by flow cytometery at 9 days of gestation. The embryo-resorption rate was counted at 14 days of gestation. The results showed that the adoptive transfer of the embryo-antigen tolerant T cells of T cells from CBA/J×BALB/c matings at 4 days of gestation could reduce significantly the embryo-resportion rate, and a very lower proliferative responses and lower level of IL-2 expression of the splenocytes of recipients to paternal antigens were demonstrated in comparison with the adoptive transfer with the isotype IgG-treated T cells. It is concluded that adoptive transfer of the embryo-antigen tolerant T cells or T cells from CBA/J×BALB/c matings can induce the materno-fetal immuno-tolerance of the abortion-prone model of CBA/J×DBA/2 matings, thus preventing the maternal to fetus immuno-rejection,and leading the embryo-resportion rate of the abortion-prone model approaching to that of the normal prignancy model.

Jin Liping; Li Dajin; Wang Minyan; Zhu Xiaoyong; Zhu Ying; Yuan Minmin; Meng Yi

2004-01-01

332

Extracellular suppression allows mating by pheromone-deficient sterile mutants of Saccharomyces cerevisiae.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

MAT alpha haploids with mutations in the STE13 or KEX2 gene, and MATa haploids with mutations in the STE6 or STE14 gene, do not mate with wild-type cells of the opposite mating type. We found that such mutants were able to mate with partners that carry mutations (sst1 and sst2) that cause cells to b...

Chan, R K; Melnick, L M; Blair, L C; Thorner, J

333

Multiple Signaling Pathways Regulate Yeast Cell Death during the Response to Mating Pheromones  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Mating pheromones promote cellular differentiation and fusion of yeast cells with those of the opposite mating type. In the absence of a suitable partner, high concentrations of mating pheromones induced rapid cell death in ?25% of the population of clonal cultures independent of cell age. Rapid cel...

Zhang, Nan-Nan; Dudgeon, Drew D.; Paliwal, Saurabh; Levchenko, Andre; Grote, Eric; Cunningham, Kyle W.

334

Mating types in Paramecium and a molecular approach to their determination.  

Science.gov (United States)

Mating types are expressed in ciliates for the duration of the mature period of their clonal cycle. During cell conjugation the reciprocal fertilization of complementary mating types takes place. Models of mating type determination in the Paramecium aurelia species complex based on classical genetics are reviewed including molecular aspects of the studies. PMID:22428300

Sawka, Natalia

2012-01-01

335

Male mating preference for female survivorship in the seaweed fly Gluma musgravei (Diptera: Coelopidae).  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The seaweed fly mating system is characterized by pre-mating struggles during which females exhibit a mate rejection response involving kicking, shaking and abdominal curling. Males must resist rejection until females become passive and allow copulation to take place. However, despite the vigorous n...

Dunn, D W; Crean, C S; Gilburn, A S

336

Microtubule Dynamics from Mating through the First Zygotic Division in the Budding Yeast Saccharomyces cerevisiae  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We have used time-lapse digital imaging microscopy to examine cytoplasmic astral microtubules (Mts) and spindle dynamics during the mating pathway in budding yeast Saccharomyces cerevisiae. Mating begins when two cells of opposite mating type come into proximity. The cells arrest in the G1 phase ...

Maddox, Paul; Chin, E.; Mallavarapu, A.; Yeh, E.; Salmon, E.D.; Bloom, K.

337

Mating types in Paramecium and a molecular approach to their determination.  

UK PubMed Central (United Kingdom)

Mating types are expressed in ciliates for the duration of the mature period of their clonal cycle. During cell conjugation the reciprocal fertilization of complementary mating types takes place. Models of mating type determination in the Paramecium aurelia species complex based on classical genetics are reviewed including molecular aspects of the studies.

Sawka N

2012-01-01

338

Sib mating without inbreeding in the longhorn crazy ant.  

UK PubMed Central (United Kingdom)

Sib matings increase homozygosity and, hence, the frequency of detrimental phenotypes caused by recessive deleterious alleles. However, many species have evolved adaptations that prevent the genetic costs associated with inbreeding. We discovered that the highly invasive longhorn crazy ant, Paratrechina longicornis, has evolved an unusual mode of reproduction whereby sib mating does not result in inbreeding. A population genetic study of P. longicornis revealed dramatic differences in allele frequencies between queens, males and workers. Mother-offspring analyses demonstrated that these allele frequency differences resulted from the fact that the three castes were all produced through different means. Workers developed through normal sexual reproduction between queens and males. However, queens were produced clonally and, thus, were genetically identical to their mothers. In contrast, males never inherited maternal alleles and were genetically identical to their fathers. The outcome of this system is that genetic inbreeding is impossible because queen and male genomes remain completely separate. Moreover, the sexually produced worker offspring retain the same genotype, combining alleles from both the maternal and paternal lineage over generations. Thus, queens may mate with their brothers in the parental nest, yet their offspring are no more homozygous than if the queen mated with a male randomly chosen from the population. The complete segregation of the male and female gene pools allows the queens to circumvent the costs associated with inbreeding and therefore may act as an important pre-adaptation for the crazy ant's tremendous invasive success.

Pearcy M; Goodisman MA; Keller L

2011-09-01

339

Sib mating without inbreeding in the longhorn crazy ant.  

Science.gov (United States)

Sib matings increase homozygosity and, hence, the frequency of detrimental phenotypes caused by recessive deleterious alleles. However, many species have evolved adaptations that prevent the genetic costs associated with inbreeding. We discovered that the highly invasive longhorn crazy ant, Paratrechina longicornis, has evolved an unusual mode of reproduction whereby sib mating does not result in inbreeding. A population genetic study of P. longicornis revealed dramatic differences in allele frequencies between queens, males and workers. Mother-offspring analyses demonstrated that these allele frequency differences resulted from the fact that the three castes were all produced through different means. Workers developed through normal sexual reproduction between queens and males. However, queens were produced clonally and, thus, were genetically identical to their mothers. In contrast, males never inherited maternal alleles and were genetically identical to their fathers. The outcome of this system is that genetic inbreeding is impossible because queen and male genomes remain completely separate. Moreover, the sexually produced worker offspring retain the same genotype, combining alleles from both the maternal and paternal lineage over generations. Thus, queens may mate with their brothers in the parental nest, yet their offspring are no more homozygous than if the queen mated with a male randomly chosen from the population. The complete segregation of the male and female gene pools allows the queens to circumvent the costs associated with inbreeding and therefore may act as an important pre-adaptation for the crazy ant's tremendous invasive success. PMID:21288949

Pearcy, Morgan; Goodisman, Michael A D; Keller, Laurent

2011-02-02

340

Mating-type genes and MAT switching in Saccharomyces cerevisiae.  

UK PubMed Central (United Kingdom)

Mating type in Saccharomyces cerevisiae is determined by two nonhomologous alleles, MATa and MAT?. These sequences encode regulators of the two different haploid mating types and of the diploids formed by their conjugation. Analysis of the MATa1, MAT?1, and MAT?2 alleles provided one of the earliest models of cell-type specification by transcriptional activators and repressors. Remarkably, homothallic yeast cells can switch their mating type as often as every generation by a highly choreographed, site-specific homologous recombination event that replaces one MAT allele with different DNA sequences encoding the opposite MAT allele. This replacement process involves the participation of two intact but unexpressed copies of mating-type information at the heterochromatic loci, HML? and HMRa, which are located at opposite ends of the same chromosome-encoding MAT. The study of MAT switching has yielded important insights into the control of cell lineage, the silencing of gene expression, the formation of heterochromatin, and the regulation of accessibility of the donor sequences. Real-time analysis of MAT switching has provided the most detailed description of the molecular events that occur during the homologous recombinational repair of a programmed double-strand chromosome break.

Haber JE

2012-05-01

 
 
 
 
341

Spermidine promotes mating and fertilization efficiency in model organisms.  

Science.gov (United States)

Spermidine is a naturally occurring polyamine involved in multiple biological processes, including DNA metabolism, autophagy and aging. Like other polyamines, spermidine is also indispensable for successful reproduction at several stages. However, a direct influence on the actual fertilization process, i.e., the fusion of an oocyte with a spermatocyte, remains uncertain. To explore this possibility, we established the mating process in the yeast Saccharomyces cerevisiae as a model for fertilization in higher eukaryotes. During human fertilization, the sperm capacitates and the acrosome reaction is necessary for penetration of the oocyte. Similarly, sexually active yeasts form a protrusion called "shmoo" as a prerequisite for mating. In this study, we demonstrate that pheromone-induced shmoo formation requires spermidine. In addition, we show that spermidine is essential for mating in yeast as well as for egg fertilization in the nematode Caenorhabditis elegans. In both cases, this occurs independently from autophagy. In synthesis, we identify spermidine as an important mating component in unicellular and multicellular model organisms, supporting an unprecedented evolutionary conservation of the mechanisms governing fertilization-related cellular fusion. PMID:23255134

Bauer, Maria Anna; Carmona-Gutiérrez, Didac; Ruckenstuhl, Christoph; Reisenbichler, Angela; Megalou, Evgenia V; Eisenberg, Tobias; Magnes, Christoph; Jungwirth, Helmut; Sinner, Frank M; Pieber, Thomas R; Fröhlich, Kai-Uwe; Kroemer, Guido; Tavernarakis, Nektarios; Madeo, Frank

2012-01-15

342

Trace elements in different brands of yerba mate tea.  

Science.gov (United States)

Yerba mate (Ilex paraguariensis), a widely consumed beverage in South America, contains various biochemically active substances, among them are several minerals. This paper reports on the results of a survey of trace elements in the yerba mate infusions. Three different commercially available trademarks of I. paraguariensis were evaluated, simulating the popular mode of preparation. Atomic absorption analyses for cadmium, lead, copper, zinc, aluminum, iron, chromium, manganese, molybdenum, and silver were performed using a graphite furnace. The levels ranged from 0.03 to 0.06 mg/L for copper, from 0.41 to 1.0 mg/L for zinc, from 0.32 to 1.7 mg/L for aluminum, from 0.12 to 0.23 mg/L for iron, from 2.3 to 7.0 mg/L for manganese, and from 0.01 to 0.03 mg/L for silver. The levels of chromium did not exceed 0.005 mg/L, while molybdenum, cadmium, and lead were lower than <0.01 mg/L. Metal content in mate tea infusions depends on a number of factors, some of which are controllable and others not, but the differences among various sources are admissible. Trace elements in mate plants seem to be weakly bounded to the substrate. The concentration of biometals does not exceed the limits accepted by Brazilian and international legislation when available. PMID:21487890

Bragança, Victor Luiz Cordoba; Melnikov, Petr; Zanoni, Lourdes Zélia

2011-04-13

343

Boatswain's Mate F1 and C: Naval Rate Training Manual.  

Science.gov (United States)

|The Rate Training Manual and Nonresident Career Course (RTM/NRCC) form a self-study package that enables Aviation Boatswain's Mate F to fulfill the requirements for advancement to ABF1 and the ABF1 for advancement to the rank of ABFC. In preparing for advancement examinations, the manual should be studied in conjunction with Military Requirements…

Naval Education and Training Command, Pensacola, FL.

344

Variation in mate recognition specificities among four Callosobruchus seed beetles  

UK PubMed Central (United Kingdom)

Differentiation of mate recognition systems is one of the important steps for speciation in animals. For some insects, a contact sex pheromone present on the cuticular surface is indispensable in discriminating reproductive partners. In Callosobruchus species (Coleoptera: Chrysomelidae: Bruchinae), contact sex pheromones have been found in two species, Callosobruchus chinensis (L.) and Callosobruchus maculatus (Fabricius). It was suggested, however, that these two species lacked the ability to discriminate their conspecific and/or heterosexual partners. To elucidate this inconsistency, we verified the existence of contact sex pheromones from two other species, Callosobruchus rhodesianus (Pic) and Callosobruchus analis (Fabricius). As a result, unlike C. chinensis and C. maculatus, the males of C. rhodesianus and C. analis were able to discriminate their heterosexual partners. Comparing cross-copulation behavior, i.e., copulation behavior between two species, against these four species indicated that the mate recognition specificities were quite different. Males of C. rhodesianus and C. analis had highly species-specific mating behavior, whereas males of C. chinensis and C. maculatus were much less specific. These results indicate that variation in mate recognition can arise even among congeneric species living in a sympatric environment, and this variation might have arisen during species differentiation. Based on our results in combination with previous reports on interspecific competition, we suggest that the observed asymmetric cross-copulation behavior might be, at least partially, an adaptation for surviving interspecific competition.

Shimomura Kenji; Mimura Takanori; Ishikawa Susumu; Yajima Shunsuke; Ohsawa Kanju

2010-06-01

345

Trace elements in different brands of yerba mate tea.  

UK PubMed Central (United Kingdom)

Yerba mate (Ilex paraguariensis), a widely consumed beverage in South America, contains various biochemically active substances, among them are several minerals. This paper reports on the results of a survey of trace elements in the yerba mate infusions. Three different commercially available trademarks of I. paraguariensis were evaluated, simulating the popular mode of preparation. Atomic absorption analyses for cadmium, lead, copper, zinc, aluminum, iron, chromium, manganese, molybdenum, and silver were performed using a graphite furnace. The levels ranged from 0.03 to 0.06 mg/L for copper, from 0.41 to 1.0 mg/L for zinc, from 0.32 to 1.7 mg/L for aluminum, from 0.12 to 0.23 mg/L for iron, from 2.3 to 7.0 mg/L for manganese, and from 0.01 to 0.03 mg/L for silver. The levels of chromium did not exceed 0.005 mg/L, while molybdenum, cadmium, and lead were lower than <0.01 mg/L. Metal content in mate tea infusions depends on a number of factors, some of which are controllable and others not, but the differences among various sources are admissible. Trace elements in mate plants seem to be weakly bounded to the substrate. The concentration of biometals does not exceed the limits accepted by Brazilian and international legislation when available.

Bragança VL; Melnikov P; Zanoni LZ

2011-12-01

346

Spermidine promotes mating and fertilization efficiency in model organisms.  

UK PubMed Central (United Kingdom)

Spermidine is a naturally occurring polyamine involved in multiple biological processes, including DNA metabolism, autophagy and aging. Like other polyamines, spermidine is also indispensable for successful reproduction at several stages. However, a direct influence on the actual fertilization process, i.e., the fusion of an oocyte with a spermatocyte, remains uncertain. To explore this possibility, we established the mating process in the yeast Saccharomyces cerevisiae as a model for fertilization in higher eukaryotes. During human fertilization, the sperm capacitates and the acrosome reaction is necessary for penetration of the oocyte. Similarly, sexually active yeasts form a protrusion called "shmoo" as a prerequisite for mating. In this study, we demonstrate that pheromone-induced shmoo formation requires spermidine. In addition, we show that spermidine is essential for mating in yeast as well as for egg fertilization in the nematode Caenorhabditis elegans. In both cases, this occurs independently from autophagy. In synthesis, we identify spermidine as an important mating component in unicellular and multicellular model organisms, supporting an unprecedented evolutionary conservation of the mechanisms governing fertilization-related cellular fusion.

Bauer MA; Carmona-Gutiérrez D; Ruckenstuhl C; Reisenbichler A; Megalou EV; Eisenberg T; Magnes C; Jungwirth H; Sinner FM; Pieber TR; Fröhlich KU; Kroemer G; Tavernarakis N; Madeo F

2013-01-01

347

Stratification in the Early Stages of Mate Choice  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Sociologists have long studied mate choice patterns to understand the shape of stratification systems. Romantic pairing involves intimacy and trust, and is therefore a prime indicator of the extent to which members of different social groupings (race/ethnicity, social class, education, religion) acc...

Lewis, Kevin

348

Method for identifying hypsizigus marmoreus mating type gene  

UK PubMed Central (United Kingdom)

The invention provides a method for performing mating type gene identification on a basidiospore monocaryon strain which is separated from different hypsizigus marmoreus strains. In the identifying process, in particular application of a flushing reaction, a palisade reaction and transplanting, the method can primarily identify the mating type gene of the hypsizigus marmoreus intuitively and quickly without other instruments and equipment. When the method is applied in cross breeding, the mating type gene of basidiospore monocaryon parent and progeny strains can be identified conveniently so as to improve the purposiveness and the effectiveness of the cross breeding process. The adopted method can shorten the time for identifying the mating type gene for 5 to 10 days, reduce the number of comparing-screening strains by 75 percent theoretically in cross breeding, improve the fecundity, and is more convenient and efficient particularly in application of multiple cross breeding of multiple strains. Then, the method selects the compatible basidiospore monocaryon strain having clamp connection according to the identification result to carry out biparental crossing, and screens hybrid strains according to growth speed, growth potential and economical character index, thereby obtaining stable, high yield and high quality hybrid strains.

ZHIYONG FENG; MINGGUANG LIU; JUNHUI GAO; MINGJIE CHEN; HUI CHEN

349

Evolution of mate-harm, longevity and behaviour in male fruit flies subjected to different levels of interlocus conflict.  

UK PubMed Central (United Kingdom)

BACKGROUND: Interlocus conflict predicts (a) evolution of traits, beneficial to males but detrimental to females and (b) evolution of aging and life-span under the influence of the cost of bearing these traits. However, there are very few empirical investigations shedding light on these predictions. Those that do address these issues, mostly reported response of male reproductive traits or the lack of it and do not address the life-history consequence of such evolution. Here, we test both the above mentioned predictions using experimental evolution on replicate populations of Drosophila melanogaster. We present responses observed after >45 generations of altered levels of interlocus conflict (generated by varying the operational sex ratio). RESULTS: Males from the male biased (high conflict, M-regime) regime evolved higher spontaneous locomotor activity and courtship frequency. Females exposed to these males were found to have higher mortality rate. Males from the female biased regime (low conflict, F-regime) did not evolve altered courtship frequency and activity. However, progeny production of females continuously exposed to F-males was significantly higher than the progeny production of females exposed to M-males indicating that the F-males are relatively benign towards their mates. We found that males from male biased regime lived shorter compared to males from the female biased regime. CONCLUSION: F-males (evolving under lower levels of sexual conflict) evolved decreased mate harming ability indicating the cost of maintenance of the suit of traits that cause mate-harm. The M-males (evolving under higher levels sexual conflict) caused higher female mortality indicating that they had evolved increased mate harming ability, possibly as a by product of increased reproduction related activity. There was a correlated evolution of life-history of the M and F-males. M-regime males lived shorter compared to the males from F-regime, possibly due to the cost of investing more in reproductive traits. In combination, these results suggest that male reproductive traits and life-history traits can evolve in response to the altered levels of interlocus sexual conflict.

Nandy B; Gupta V; Sen S; Udaykumar N; Samant MA; Ali SZ; Prasad NG

2013-09-01

350

Crossing boundaries: nativity, ethnicity, and mate selection.  

UK PubMed Central (United Kingdom)

The influx of immigrants has increased diversity among ethnic minorities and indicates that they may take multiple integration paths in American society. Previous research on ethnic integration has often focused on panethnic differences, and few have explored ethnic diversity within a racial or panethnic context. Using 2000 U.S. census data for Puerto Rican-, Mexican-, Chinese-, and Filipino-origin individuals, we examine differences in marriage and cohabitation with whites, with other minorities, within a panethnic group, and within an ethnic group by nativity status. Ethnic endogamy is strong and, to a lesser extent, so is panethnic endogamy. Yet, marital or cohabiting unions with whites remain an important path of integration but differ significantly by ethnicity, nativity, age at arrival, and educational attainment. Meanwhile, ethnic differences in marriage and cohabitation with other racial or ethnic minorities are strong. Our analysis supports that unions with whites remain a major path of integration, but other paths of integration also become viable options for all ethnic groups.

Qian Z; Glick JE; Batson CD

2012-05-01

351

Aphrodisiac Pheromone and its role in mating behaviour of Gamma irradiated SPODOPTERA LITTORALIS (BOISD.)  

International Nuclear Information System (INIS)

The aphrodisiac pheromone in male moth of the cotton leaf worm, Spodoptera littoralis, is secreted from a scent gland that lies in the fore wings and hair pencils. The damage of the gland by gamma irradiation or elimination of the fore wings reduced mating percentage and the other related mating aspects. Multiple mating seldom was occurred in the eliminated wing males and this mean that the wing gland was effective in mating behaviour. The knowledge on pheromone glands and their role in mating behaviour have been appeared to be essential in the integrated control programmes.

2007-01-01

352

Mating frequency in male Japanese quail: crosses among selected and unselected lines.  

UK PubMed Central (United Kingdom)

The genetics of mating behavior in Japanese quail was investigated in replicated lines selected for high or low number of completed matings and the random bred control which served as the base population for the selected lines. Comparisons involved the parental lines, F1, F2, and backcross generations. Results indicate that mating frequency is influenced by additive and nonadditive genetic variation with the former being the primary heritable influence. The relationships between mating behavior, cloacal gland size, and relative aggressiveness suggest that selection for mating frequency influences factors commonly affecting these traits.

Bernon DE; Siegel PB

1983-10-01

353

Courtship disruption modifies mate choice in a lek-breeding bird.  

UK PubMed Central (United Kingdom)

The aggregation of displaying males in lek-breeding birds is often associated with disruption of courtship and mating but effects of this disruption on mate choice have not been shown. In a 4-year study of Rupicola rupicola in Suriname, interference among territorial adult males disrupted 31 percent of all female courtship visits and terminated 32 percent of all matings at a lek where there were an average of 55 territorial males. Disruption in this rain forest species caused females to modify their courtship and mating patterns, and males that used intense and persistent disruption received a disproportionate share of this redirected mate choice.

Trail PW

1985-02-01

354

Sperm precedence in female apple maggots alternately mated to normal and irradiated males  

International Nuclear Information System (INIS)

[en] A dose of irradiation (Cesium 137) of 3 krad was sufficient to sterilize both sexes of the apple maggot, Rhagoletis pomonella (Walsh). When the irradiated male (IM) mated with normal female (NF), egg production was not reduced compared with a normal mating, but the eggs were not viable. Also, two matings of 1 NF with either 2 IM or with 1 NM and 1 IM, produced fewer eggs than a single mating with 1 normal male. Sperm precedence exhibited for the 2nd of the 2 matings was not complete

1976-01-15

355

Employing mated females as recipients for transfer of cloned dog embryos.  

UK PubMed Central (United Kingdom)

It has been suggested that co-transferring parthenogenetic embryos could improve the pregnancy success rate with cloned embryos in mammals. As an alternative to co-transferring parthenotes, in dogs we employed recipient females that possessed in vivo-fertilised embryos as a result of mating to determine whether mated bitches could be suitable recipients for cloned embryos. The effect of using mated recipients on implantation and pregnancy rates of canine somatic cell nuclear transfer embryos was also determined. Cloned embryos were transferred into the oviducts of naturally synchronous females that had mated with male dogs before ovulation. The pregnancy rate appeared to be similar between mated recipients (50%) and non-mated recipients (28.57%; P>0.05). However, the delivery rate of cloned pups was significantly higher in mated recipients than non-mated recipients (10.53 vs 2.38%; P<0.05). A decrease in progesterone levels in the mated recipients before the due date induced natural delivery. However, cloned pups in non-mated recipients were delivered by Caesarean section because the fall in progesterone concentration in these females did not occur until the due date. The present study demonstrated for the first time that mated female dogs can be used as recipients for cloned embryos.

Kim GA; Oh HJ; Park JE; Kim MJ; Park EJ; Lim SH; Kang SK; Jang G; Lee BC