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1

Saccharin consumption increases sperm DNA fragmentation and apoptosis in mice  

PubMed Central

Background: Saccharin is an artificial non-caloric sweetener that used to sweeten products such as drinks, candies, medicines, and toothpaste, but our bodies cannot metabolize it. Sodium saccharin is considered as an important factor in tumor promotion in male rats but not in humans. Objective: The objective of this study was to investigate the effect of saccharin consumption on sperm parameters and apoptosis in adult mice. Materials and Methods: Totally 14 adult male mice were divided into 2 groups. Group 1 served as control fed on basal diet and group 2 or experimental animals received distilled water containing saccharin (0.2% w/v) for 35 days. After that, the left cauda epididymis of each mouse was cut and placed in Ham’s F10. Swimmed-out spermatozoa were used to analyze count, motility, morphology (Pap-staining) and viability (eosin-Y staining). Sperm DNA integrity, as an indicator of apoptosis, was assessed by SCD (sperm chromatin dispersion) and terminal deoxynucleotidyl transferase (TUNEL) assay. Results: Following saccharin consumption, we had a reduction in sperm motility with respect to control animals (p=0.000). In addition, the sperm count diminished (17.70±1.11 in controls vs. 12.80±2.79 in case group, p=0.003) and the rate of sperm normal morphology decreased from 77.00±6.40 in control animals into 63.85±6.81 in saccharin-treated mice (p=0.001). Also, we saw a statistically significant increase in rates of sperm DNA damage and apoptosis in experimental group when compared to control one (p=0.001, p=0.002 respectively). Conclusion: Saccharin consumption may have negative effects on sperm parameters, and increases the rate of sperm DNA fragmentation and apoptosis in mice. PMID:25031574

Rahimipour, Marzieh; Talebi, Ali Reza; Anvari, Morteza; Abbasi Sarcheshmeh, Abolghasem; Omidi, Marjan

2014-01-01

2

Male body size and condition affects sperm number and production rates in mosquitofish, Gambusia holbrooki.  

PubMed

Sperm number is an important predictor of paternity when there is sperm competition. Sperm number is often measured as maximum sperm reserves, but in species where mating is frequent, males will often be replenishing their reserves. Thus, variation in how quickly males can produce sperm is likely to be important in determining male success in sperm competition. Despite this, little is known about how male size, body condition or diet affects sperm production rates. We counted sperm number in large and small Gambusia holbrooki (eastern mosquitofish) after 3 weeks on either a high or low food diet. Sperm number was significantly higher in both larger males and in well-fed males. We then stripped ejaculates again either 1, 2, 3, 4 or 5 days later to investigate subsequent sperm production. The rate of sperm replenishment was influenced by an interaction between size and diet. Large, well-fed males had consistently high levels of sperm available over the 5 days (i.e. rapid replenishment), whereas small poorly fed males showed consistently low levels of sperm availability over the 5 days (i.e. slow replenishment). In contrast, large, poorly fed and small, well-fed males increased their sperm numbers over the first 3 days (i.e. intermediate replenishment). Our study highlights that when mating is frequent and sperm competition is high, size and condition dependence of maximal sperm number and of sperm production rate might both contribute to variation in male reproductive success. PMID:25403851

O'Dea, R E; Jennions, M D; Head, M L

2014-12-01

3

Phenotypic engineering of sperm-production rate confirms evolutionary predictions of sperm competition theory  

PubMed Central

Sperm production is a key male reproductive trait and an important parameter in sperm competition theory. Under sperm competition, paternity success is predicted to depend strongly on male allocation to sperm production. Furthermore, because sperm production is inherently costly, individuals should economize in sperm expenditure, and conditional adjustment of the copulation frequency according to their sperm availability may be expected. However, experimental studies showing effects of sperm production on mating behaviour and paternity success have so far been scarce, mainly because sperm production is difficult to manipulate directly in animals. Here, we used phenotypic engineering to manipulate sperm-production rate, by employing dose-dependent RNA interference (RNAi) of a spermatogenesis-specific gene, macbol1, in the free-living flatworm Macrostomum lignano. We demonstrate (i) that our novel dose-dependent RNAi approach allows us to induce high variability in sperm-production rate; (ii) that a reduced sperm-production rate is associated with a decreased copulation frequency, suggesting conditional adjustment of mating behaviour; and (iii) that both sperm production and copulation frequency are important determinants of paternity success in a competitive situation, as predicted by sperm competition theory. Our study clearly documents the potential of phenotypic engineering via dose-dependent RNAi to test quantitative predictions of evolutionary theory. PMID:23446521

Sekii, Kiyono; Vizoso, Dita B.; Kuales, Georg; De Mulder, Katrien; Ladurner, Peter; Schärer, Lukas

2013-01-01

4

Production of live foals via intracytoplasmic injection of lyophilized sperm and sperm extract in the horse.  

PubMed

Work with lyophilized sperm helps delineate the factors required for successful fertilization. We investigated the use of lyophilized sperm in equine embryo production. In Experiment 1, sperm DNA fragmentation index was not affected by three freeze/thaw or lyophilization cycles. In Experiment 2, oocytes injected with lyophilized sperm or with sperm from a treatment in which lyophilized sperm were suspended in sperm cytoplasmic extract (SE) yielded blastocyst development rates of 0 and 28% respectively (P < 0.05). In Experiment 3, blastocyst development rate was 6-11% after injection of sperm lyophilized from fresh or frozen-thawed semen, suspended in SE. In Experiment 4, sperm lyophilized 3.5 months or 1 week previously, suspended in SE, yielded similar blastocyst rates (6 and 3% respectively). Rates of normal pregnancy after transfer were 7/10 and 5/7 for embryos from control and lyophilized sperm treatments respectively. Three pregnancies from the lyophilized sperm treatments were not terminated, resulting in two healthy foals. Parentage testing determined that one foal originated from the lyophilized sperm; the other was the offspring of the stallion providing the sperm extract. Further testing indicated that two of five additional embryos in the lyophilized sperm treatment originated from the stallion providing the sperm extract. We conclude that both lyophilized stallion sperm and stallion sperm processed by multiple unprotected freeze-thaw cycles (as for sperm extract) can support production of viable foals. To the best of our knowledge, this is the first report on production of live offspring by fertilization with lyophilized sperm in a non-laboratory animal species. PMID:21846810

Choi, Y H; Varner, D D; Love, C C; Hartman, D L; Hinrichs, K

2011-10-01

5

Sperm cells as vectors in the production of transgenic animals  

SciTech Connect

Transgenic animals are used in industry and in biomedical research in order to provide in vivo experimental model systems. Sperm cells have been reported used as vectors in the production of transgenic animals before, however no approach has of yet proven to be successful. Fertilizing eggs with genetically modified sperm would be advantageous in that sperm are readily accessible and stable, and eggs can be fertilized by modified sperm cells in vivo. Recent elucidations regarding the unique manner of DNA packaging in sperm chromatin by protamines has provided us with the insight for developing a method of introducing foreign DNA into sperm which is likely to succeed where others have failed. We have developed a method for mimicking the in vivo system of sperm chromatin toroid subunits in vitro, concentrating these toroids, and fluorescent visualization. Our present work concerns development of a method to successfully deliver DNA across the cell membranes and into the nucleus.

Prince, R.M.

1993-04-28

6

Under-nutrition reduces spermatogenic efficiency and sperm velocity, and increases sperm DNA damage in sexually mature male sheep.  

PubMed

We tested whether the quality of spermatozoa from mature male sheep would be affected during nutrition-induced changes in testicular mass. Merino rams were fed for 65 days with diets that increased, maintained or decreased body and testis mass (n=8 per group). In semen collected on Days 56 and 63, underfed rams had less sperms per ejaculate than well-fed rams (P<0.05) and a lower sperm velocity (computer-assisted semen analysis) than well-fed or maintenance-fed rams (P<0.05). Sperm chromatin structure assay revealed more sperm DNA damage in underfed rams than in well-fed rams (P<0.05). The amount of sperm DNA damage was inversely correlated with change in scrotal circumference (r=-0.6, P<0.05), the percentages of progressive motile sperm (r=-0.8; P<0.01) and motile sperm (r=-0.6, P<0.05), and the numbers of sperms per gram of testis (r=-0.55, P<0.05). In testicular tissue collected on Day 65, underfed rams had fewer sperm per gram of testis than rams in the other two groups (P<0.001). We conclude that, in adult rams, underfeeding reduces spermatogenic efficiency and that this response is associated with a reduction in spermatozoal quality. PMID:25086661

Guan, Yongjuan; Malecki, Irek A; Hawken, Penelope A R; Linden, Matthew D; Martin, Graeme B

2014-10-01

7

Sperm Competition, Sperm Numbers and Sperm Quality in Muroid Rodents  

Microsoft Academic Search

Sperm competition favors increases in relative testes mass and production efficiency, and changes in sperm phenotype that result in faster swimming speeds. However, little is known about its effects on traits that contribute to determine the quality of a whole ejaculate (i.e., proportion of motile, viable, morphologically normal and acrosome intact sperm) and that are key determinants of fertilization success.

Laura Gómez Montoto; Concepción Magaña; Maximiliano Tourmente; Juan Martín-Coello; Cristina Crespo; Juan José Luque-Larena; Montserrat Gomendio; Eduardo R. S. Roldan; Neil Gemmell

2011-01-01

8

No increased sperm DNA fragmentation index in semen containing human papillomavirus or herpesvirus.  

PubMed

It remains unknown whether human papillomaviruses (HPVs) or human herpesviruses (HHVs) in semen affect sperm DNA integrity. We investigated whether the presence of these viruses in semen was associated with an elevated sperm DNA fragmentation index. Semen from 76 sperm donors was examined by a PCR-based hybridization array that identifies all HHVs and 35 of the most common HPVs. Sperm DNA integrity was determined by the sperm chromatin structure assay. HPVs or HHVs, or both, were found in 57% of semen samples; however, sperm DNA fragmentation index was not increased in semen containing these viruses. PMID:23444031

Kaspersen, M D; Bungum, M; Fedder, J; Bonde, J; Larsen, P B; J Ingerslev, H; Höllsberg, P

2013-05-01

9

Sperm Competition, Sperm Numbers and Sperm Quality in Muroid Rodents  

PubMed Central

Sperm competition favors increases in relative testes mass and production efficiency, and changes in sperm phenotype that result in faster swimming speeds. However, little is known about its effects on traits that contribute to determine the quality of a whole ejaculate (i.e., proportion of motile, viable, morphologically normal and acrosome intact sperm) and that are key determinants of fertilization success. Two competing hypotheses lead to alternative predictions: (a) sperm quantity and quality traits co-evolve under sperm competition because they play complementary roles in determining ejaculate's competitive ability, or (b) energetic constraints force trade-offs between traits depending on their relevance in providing a competitive advantage. We examined relationships between sperm competition levels, sperm quantity, and traits that determine ejaculate quality, in a comparative study of 18 rodent species using phylogenetically controlled analyses. Total sperm numbers were positively correlated to proportions of normal sperm, acrosome integrity and motile sperm; the latter three were also significantly related among themselves, suggesting no trade-offs between traits. In addition, testes mass corrected for body mass (i.e., relative testes mass), showed a strong association with sperm numbers, and positive significant associations with all sperm traits that determine ejaculate quality with the exception of live sperm. An “overall sperm quality” parameter obtained by principal component analysis (which explained 85% of the variance) was more strongly associated with relative testes mass than any individual quality trait. Overall sperm quality was as strongly associated with relative testes mass as sperm numbers. Thus, sperm quality traits improve under sperm competition in an integrated manner suggesting that a combination of all traits is what makes ejaculates more competitive. In evolutionary terms this implies that a complex network of genetic and developmental pathways underlying processes of sperm formation, maturation, transport in the female reproductive tract, and preparation for fertilization must all evolve in concert. PMID:21464956

Gómez Montoto, Laura; Magaña, Concepción; Tourmente, Maximiliano; Martín-Coello, Juan; Crespo, Cristina; Luque-Larena, Juan José

2011-01-01

10

Bower-building behaviour is associated with increased sperm longevity in Tanganyikan cichlids.  

PubMed

We investigated the evolutionary relationship between spawning behaviour and sperm motility traits among Tanganyikan mouth-brooding cichlid species that have developed diverse mating behaviours and male sexual traits. Mouth-brooding behaviour is common among these fish, but different species demonstrate a range of spawning behaviours, bower construction, male sexual traits and timing of gamete release. We observed spawning behaviours and compared sperm motility traits of 28 Tanganyikan mouth-brooding cichlids to elucidate the evolutionary correlations between these traits. Sperm longevity was considerably longer in bower-building species that construct crater-shaped spawning sites compared with species that do not build bowers. Male bower builders released sperm in the pit of the bower prior to spawning, and the time from ejaculation to fertilization was longer. Conversely, most mouth-brooding cichlids deposited semen directly into the female buccal cavity, and spawned eggs were immediately picked up to be placed inside the cavity; thus, the time from ejaculation to fertilization was short. These observations suggest that increased sperm longevity is favoured in bower builders. Comparative phylogenetic analyses suggested that bower-building behaviour and greater time from ejaculation to fertilization are associated with the extension of sperm longevity, whereas sperm competition rank does not play a major role. In addition, bower-building behaviour preceded the emergence of increased sperm longevity. These results indicate that the extension of sperm longevity as a result of the emergence of bower builders may have acted as an evolutionary attractor for sperm longevity. PMID:25330280

Morita, M; Awata, S; Yorifuji, M; Ota, K; Kohda, M; Ochi, H

2014-12-01

11

Frequency of XY Sperm Increases with Age in Fathers of Boys with Klinefelter Syndrome  

Microsoft Academic Search

With increasing availability of drugs for impotence and advanced reproductive technologies for the treatment of subfertility, more men are fathering children at advanced ages. We conducted a study of the chromosomal content of sperm of healthy men aged 24-57 years to (a) determine whether father's age was associated with increasing frequencies of aneuploid sperm including XY, disomy X, disomy Y,

Xiu Lowe; Brenda Eskenazi; David O. Nelson; Sharon Kidd; Angela Alme; Andrew J. Wyrobek

2001-01-01

12

Sperm Competition Selects for Sperm Quantity and Quality in the Australian Maluridae  

PubMed Central

When ejaculates from rival males compete for fertilization, there is strong selection for sperm traits that enhance fertilization success. Sperm quantity is one such trait, and numerous studies have demonstrated a positive association between sperm competition and both testes size and the number of sperm available for copulations. Sperm competition is also thought to favor increases in sperm quality and changes in testicular morphology that lead to increased sperm production. However, in contrast to sperm quantity, these hypotheses have received considerably less empirical support and remain somewhat controversial. In a comparative study using the Australian Maluridae (fairy-wrens, emu-wrens, grasswrens), we tested whether increasing levels of sperm competition were associated with increases in both sperm quantity and quality, as well as an increase in the relative amount of seminiferous tubule tissue contained within the testes. After controlling for phylogeny, we found positive associations between sperm competition and sperm numbers, both in sperm reserves and in ejaculate samples. Additionally, as sperm competition level increased, the proportion of testicular spermatogenic tissue also increased, suggesting that sperm competition selects for greater sperm production per unit of testicular tissue. Finally, we also found that sperm competition level was positively associated with multiple sperm quality traits, including the proportion of motile sperm in ejaculates and the proportion of both viable and morphologically normal sperm in sperm reserves. These results suggest multiple ejaculate traits, as well as aspects of testicular morphology, have evolved in response to sperm competition in the Australian Maluridae. Furthermore, our findings emphasize the importance of post-copulatory sexual selection as an evolutionary force shaping macroevolutionary differences in sperm phenotype. PMID:21283577

Rowe, Melissah; Pruett-Jones, Stephen

2011-01-01

13

Sperm competition selects for sperm quantity and quality in the Australian Maluridae.  

PubMed

When ejaculates from rival males compete for fertilization, there is strong selection for sperm traits that enhance fertilization success. Sperm quantity is one such trait, and numerous studies have demonstrated a positive association between sperm competition and both testes size and the number of sperm available for copulations. Sperm competition is also thought to favor increases in sperm quality and changes in testicular morphology that lead to increased sperm production. However, in contrast to sperm quantity, these hypotheses have received considerably less empirical support and remain somewhat controversial. In a comparative study using the Australian Maluridae (fairy-wrens, emu-wrens, grasswrens), we tested whether increasing levels of sperm competition were associated with increases in both sperm quantity and quality, as well as an increase in the relative amount of seminiferous tubule tissue contained within the testes. After controlling for phylogeny, we found positive associations between sperm competition and sperm numbers, both in sperm reserves and in ejaculate samples. Additionally, as sperm competition level increased, the proportion of testicular spermatogenic tissue also increased, suggesting that sperm competition selects for greater sperm production per unit of testicular tissue. Finally, we also found that sperm competition level was positively associated with multiple sperm quality traits, including the proportion of motile sperm in ejaculates and the proportion of both viable and morphologically normal sperm in sperm reserves. These results suggest multiple ejaculate traits, as well as aspects of testicular morphology, have evolved in response to sperm competition in the Australian Maluridae. Furthermore, our findings emphasize the importance of post-copulatory sexual selection as an evolutionary force shaping macroevolutionary differences in sperm phenotype. PMID:21283577

Rowe, Melissah; Pruett-Jones, Stephen

2011-01-01

14

Sperm cryopreservation in live-bearing Xiphophorus fishes: offspring production from Xiphophorus variatus and strategies for establishment of sperm repositories.  

PubMed

Cryopreservation of sperm from Xiphophorus fishes has produced live young in three species: X. hellerii, X. couchianus, and X. maculatus. In this study, the goal was to establish protocols for sperm cryopreservation and artificial insemination to produce live young in X. variatus, and to identify needs for repository development. The objectives were to: 1) collect basic biological characteristics of males; 2) cryopreserve sperm from X. variatus, 3) harvest live young from cryopreserved sperm, and 4) discuss the requirements for establishment of sperm repositories. The 35 males used in this study had a body weight of 0.298±0.096 g (mean±SD), body length of 2.5±0.2 cm, and testis weight of 6.4±3.4 mg. The sperm production per gram of testis was 2.33±1.32×10(9) cells. After freezing, the post-thaw motility decreased significantly to 37%±17% (ranging from 5% to 70%) (p=0.000) from 57%±14% (40%-80%) of fresh sperm (N=20). Artificial insemination of post-thaw sperm produced confirmed offspring from females of X. hellerii and X. variatus. This research, taken together with previous studies, provides a foundation for development of strategies for sperm repositories of Xiphophorus fishes. This includes: 1) the need for breeding strategies for regeneration of target populations, 2) identification of minimum fertilization capacity of frozen samples, 3) identification of fish numbers necessary for sampling and their genetic relationships, 4) selection of packaging containers for labeling and biosecurity, 5) assurance of quality control and standardization of procedures, 6) information systems that can manage the data associated with cryopreserved samples, including the genetic data, 7) biological data of sampled fish, 8) inventory data associated with frozen samples, and 9) data linking germplasm samples with other related materials such as body tissues or cells saved for DNA and RNA analyses. PMID:22924335

Yang, Huiping; Cuevas-Uribe, Rafael; Savage, Markita G; Walter, Ronald B; Tiersch, Terrence R

2012-09-01

15

Sperm Cryopreservation in Live-Bearing Xiphophorus Fishes: Offspring Production from Xiphophorus variatus and Strategies for Establishment of Sperm Repositories  

PubMed Central

Abstract Cryopreservation of sperm from Xiphophorus fishes has produced live young in three species: X. hellerii, X. couchianus, and X. maculatus. In this study, the goal was to establish protocols for sperm cryopreservation and artificial insemination to produce live young in X. variatus, and to identify needs for repository development. The objectives were to: 1) collect basic biological characteristics of males; 2) cryopreserve sperm from X. variatus, 3) harvest live young from cryopreserved sperm, and 4) discuss the requirements for establishment of sperm repositories. The 35 males used in this study had a body weight of 0.298±0.096?g (mean±SD), body length of 2.5±0.2?cm, and testis weight of 6.4±3.4?mg. The sperm production per gram of testis was 2.33±1.32×109 cells. After freezing, the post-thaw motility decreased significantly to 37%±17% (ranging from 5% to 70%) (p=0.000) from 57%±14% (40%–80%) of fresh sperm (N=20). Artificial insemination of post-thaw sperm produced confirmed offspring from females of X. hellerii and X. variatus. This research, taken together with previous studies, provides a foundation for development of strategies for sperm repositories of Xiphophorus fishes. This includes: 1) the need for breeding strategies for regeneration of target populations, 2) identification of minimum fertilization capacity of frozen samples, 3) identification of fish numbers necessary for sampling and their genetic relationships, 4) selection of packaging containers for labeling and biosecurity, 5) assurance of quality control and standardization of procedures, 6) information systems that can manage the data associated with cryopreserved samples, including the genetic data, 7) biological data of sampled fish, 8) inventory data associated with frozen samples, and 9) data linking germplasm samples with other related materials such as body tissues or cells saved for DNA and RNA analyses. PMID:22924335

Cuevas-Uribe, Rafael; Savage, Markita G.; Walter, Ronald B.; Tiersch, Terrence R.

2012-01-01

16

Partial and total fish meal replacement by agricultural products in the diets improve sperm quality in African catfish (Clarias gariepinus).  

PubMed

This study investigated the long-term effects of total and partial replacement of dietary fish meal (FM) by a mixture of agricultural products on sperm quality of African catfish Clarias gariepinus. Four isonitrogenous and isoenergetic diets were formulated containing graded levels of either 50% FM and maize meal (diet 1); 25% FM mixed with crude sunflower oil cake (SFOC) and bean meal (BM) (diet 2); 12.5% FM mixed with sunflower oil cake, BM and ground nut oil cake (GOC) (diet 3) and 0% FM mixed with de-hulled sunflower oil cake (SFOCD), BM and ground nut oil cake (diet 4). Gonadosomatic index (GSI), sperm quality, plasma sex steroids (11-keto testosterone [11-KT]; testosterone [T]; estradiol-17beta [E2]) were evaluated on 10 to 24 fish fed on each diet. Sperm quality was assessed using computer-assisted sperm analysis (CASA). Total replacement of fish meal by plant products markedly increased sperm volume, spermatocrit, spermatozoa integrity, and sperm motility. Fish fed diet 3 (12.5% fish meal) provided intermediate results on sperm quality whereas the lowest values were obtained in fish fed diets 1 and 2. In fish fed 0% fish meal (diet 4), androgen levels were higher and estrogen levels were lower than in fish fed fish meal diets. Based on dietary lipid and fatty acid analyses, these results suggest a positive impact of short chain n-6 fatty acids on androgen synthesis and sperm quality. In conclusion, a combination of ground nut oil cake, bean meal and sunflower oil cake (preferably when the sunflower is dehulled) in African catfish diet improves the sperm quality. PMID:22015161

Nyina-Wamwiza, L; Milla, S; Pierrard, M-A; Rurangwa, E; Mandiki, S N M; Van Look, K J W; Kestemont, P

2012-01-01

17

Human sperm competition: testis size, sperm production and rates of extrapair copulations  

E-print Network

reflects a balanced polymorphism between men who specialize in sperm competition through EPCs and men who reserved. When sperm from two or more males are present within the reproductive tract of a single female as a pervasive force in evolution, favouring adaptations in males for gaining fertilizations (reviewed

Clifton, Ken

18

Membrane progestin receptor alpha mediates progestin-induced sperm hypermotility and increased fertilization success in southern flounder (Paralichthys lethostigma).  

PubMed

Progestin hormones stimulate sperm motility in teleosts but their mechanisms of action remain unclear. Preliminary results suggest that progestin upregulation of sperm motility in southern flounder and several other marine species is mediated through a sperm membrane progestin receptor with the characteristics of membrane progestin receptor alpha (mPR?, also known as Paqr7b). The hypothesis that mPR? has an important role in progestin regulation of southern flounder sperm motility and fertility was tested in the present study. The specific mPR? agonist, 10-ethenyl-19-norprogesterone (Org OD 02-0, 100nM), mimicked the stimulatory actions of the endogenous progestin, 17,20?, 21-trihydroxy-4-pregnen-3-one (20?-S, 100nM) on flounder sperm motility. The concentration of the mPR? protein on sperm plasma membranes was positively correlated to sperm motility as well as the responsiveness of sperm to progestin stimulation. Acute in vitro progestin treatment of sperm with high mPR? protein levels increased both sperm motility and fertilization success in strip spawning experiments. However, in vitro progestin treatments were ineffective on sperm with low receptor abundance. A single injection of the superactive gonadotropin-releasing hormone analog (LHRHa, 100?g/kg) increased sperm motility and fertilization success in strip spawning experiments 72h post-injection which was accompanied by an increase in mPR? protein concentrations on sperm plasma membranes. These results provide clear evidence that southern flounder sperm hypermotility is mediated through mPR?. Stimulatory G proteins, but not inhibitory G proteins, were identified in flounder sperm plasma membrane fractions. The finding that treatment of flounder sperm plasma membrane fractions with either 20?-S or Org OD 02-0 increases cAMP levels suggests progestins stimulate flounder sperm motility by activating an mPR?/stimulatory G protein/membrane adenylyl cyclase pathway. A similar mechanism has been identified in Atlantic croaker, suggesting that the signaling pathway mediated by mPR? in sperm is highly conserved in advanced teleosts. Collectively, our results indicate that progestin-stimulation of flounder sperm hypermotility and fertility is dependent on a sufficient concentration of mPR? which can be upregulated by in vivo LHRHa treatments. These findings potentially have practical applications for enhancing the fertility of male flounder broodstock. PMID:24530629

Tan, Wenxian; Aizen, Joseph; Thomas, Peter

2014-05-01

19

High quality sperm for nonhuman primate ART: Production and assessment  

PubMed Central

Factors that affect sperm quality can include method of semen collection, conditions for capacitation and whether or not agglutination is present. Media and procedures for sperm washing can also impair or improve sperm function in assisted reproductive technologies. For example, the removal of seminal fluid through large volume washing is required to eliminate decapacitation activity of seminal plasma. The forces involved with centrifugation and the metabolic stress of tightly pelleting sperm during washing procedures can have deleterious results. In contrast to human sperm, sperm from the most commonly used species of nonhuman primates, rhesus and cynomolgus macaques, do not spontaneously capacitate in vitro; rather, chemical activation with dibutryl cyclic AMP and caffeine is required. Recognizing motility patterns of non-activated and activated sperm can be accomplished with simple observation. After activation, sperm agglutination sometimes occurs and can interfere with sperm binding to the zona pellucida. Because nonhuman primate oocytes require a large investment to produce and currently, each animal can be hormonally stimulated a limited number of times, it is important to have means to evaluate quality prior to using sperm from a new male for in vitro fertilization. Methods for producing live, acrosome reacted sperm may also have application for ICSI. Because many genetically valuable males are now being identified, it may be necessary to individualize sperm preparation to accommodate male-to-male variation. PMID:15200678

VandeVoort, Catherine A

2004-01-01

20

Disruption of Maternal DNA Repair Increases Sperm-DerivedChromosomal Aberrations  

SciTech Connect

The final weeks of male germ cell differentiation occur in aDNA repair-deficient environment and normal development depends on theability of the egg to repair DNA damage in the fertilizing sperm. Geneticdisruption of maternal DNA double-strand break repair pathways in micesignificantly increased the frequency of zygotes with chromosomalstructural aberrations after paternal exposure to ionizing radiation.These findings demonstrate that radiation-induced DNA sperm lesions arerepaired after fertilization by maternal factors and suggest that geneticvariation in maternal DNA repair can modulate the risk of early pregnancylosses and of children with chromosomal aberrations of paternalorigin.

Marchetti, Francesco; Essers, Jeroun; Kanaar, Roland; Wyrobek,Andrew J.

2007-02-07

21

Increasing productivity: Another approach  

SciTech Connect

An engineering information (EI) and information technology (IT) organization that must improve its productivity should work to further its business goals. This paper explores a comprehensive model for increasing EI/IT productivity by supporting organizational objectives.

Norton, F.J.

1996-06-10

22

Reactive oxygen species production and redox state in parthenogenetic and sperm-mediated bovine oocyte activation.  

PubMed

The knowledge concerning redox and reactive oxygen species (ROS)-mediated regulation of early embryo development is scarce and remains controversial. The aim of this work was to determine ROS production and redox state during early in vitro embryo development in sperm-mediated and parthenogenetic activation of bovine oocytes. Sperm-mediated oocyte activation was carried out in IVF-modified synthetic oviductal fluid (mSOF) with frozen-thawed semen. Parthenogenetic activation was performed in TALP plus ionomycin and then in IVF-mSOF with 6-dimethylaminopurine plus cytochalasin B. Embryos were cultured in IVF-mSOF. ROS and redox state were determined at each 2-h interval (7-24?h from activation) by 2',7'-dichlorodihydrofluorescein diacetate and RedoxSensor Red CC-1 fluorochromes respectively. ROS levels and redox state differed between activated and non-activated oocytes (P<0.05 by ANOVA). In sperm-activated oocytes, an increase was observed between 15 and 19?h (P<0.05). Conversely, in parthenogenetically activated oocytes, we observed a decrease at 9?h (P<0.05). In sperm-activated oocytes, ROS fluctuated throughout the 24?h, presenting peaks around 7, 19, and 24?h (P<0.05), while in parthenogenetic activation, peaks were detected at 7, 11, and 17?h (P<0.05). In the present work, we found clear distinctive metabolic patterns between normal and parthenogenetic zygotes. Oxidative activity and ROS production are an integral part of bovine zygote behavior, and defining a temporal pattern of change may be linked with developmental competence. PMID:23630331

Morado, S; Cetica, P; Beconi, M; Thompson, J G; Dalvit, G

2013-05-01

23

Current status of plant products reported to inhibit sperm.  

PubMed

This report reviews research on plant-derived agents that prevent sperm production if taken orally by the male or that incapacitate or kill sperm on contact if used vaginally by the female. It would be of great value to develop fertility inhibitors that are totally selective for reproductive systems and enzymes, and there is a possibility that a plant-derived drug may have this effect. Plants that have been studied for their fertility inhibiting effects in the male include: Aristolochia indica L. (Aristolochiaceae); Azadirachta indica A. Juss (Meliaceae); Balanites roxburghii Planch. (Zygophyllaceae); Calotropis procera (Ait) R.Br. (Asclepiadaceae); Carica papaya L. (Caricaceae); Catharanthus roseus (L.) G. Don (Apocynaceae); Dieffenbachia seguine (Jacquin) Schott. (Araceae); Ecaballium elaterium A. Richard (Cucurbitaceae); Gossypium species (Malvaceae); Hibiscus rosa-sinensis L. (Malvaceae); Hippophae salicifolia D. Don (Elaeagnaceae); Leucaena glauca (L.) Benth. (Leguminosae); Lonicera ciliosa Poir. (Caprifoliaceae); Lupinus termis Forsk. (Leguminosae); Malvaviscus conzattii Greenm. (Malvaceae); Momordica charantia L. (Curcurbitaceae); Ocimum sanctum L. (Labiatae); Prunus emarginata Walp. (Rosaceae); and Withania somnifera (L.) Dunal (Solanaceae). A large number of plants have been randomly selected and screened for spermicidal activity "in vitro" and several seem promising. Those species found to be active and the nature of the active principle(s), when known, are presented in a table as are plant-derived chemical substances of known or partially known structure reported to be spermicidal "in vitro." Plants warrant systematic study as potential sources of sperm-agglutinating compounds. Of 1600 Indian plants tested, 90 showed positive semen coagulating properties. There seems to be a lack of correlation among experimental results obtained by different groups of investigators, between data obtained "in vitro" and "in vivo," and between experimental results and information found in folklore. Factors complicating the adequate assessment of plants affecting male fertility are inadequate numbers of vehicle-treated controls, poor experimental design, problems related to insolubility of crude plant extracts, variation in routes of administration, diversity in reproductive function and control among various laboratory species, and problems in identifying plant names consistently. PMID:12179631

Farnsworth, N R; Waller, D P

1982-06-01

24

The Healthy Men Study: An Evaluation of Exposure to Disinfection By-Products in Tap Water and Sperm Quality  

PubMed Central

Background Chlorination of drinking water generates disinfection by-products (DBPs), which have been shown to disrupt spermatogenesis in rodents at high doses, suggesting that DBPs could pose a reproductive risk to men. In this study we assessed DBP exposure and testicular toxicity, as evidenced by altered semen quality. Methods We conducted a cohort study to evaluate semen quality in men with well-characterized exposures to DBPs. Participants were 228 presumed fertile men with different DBP profiles. They completed a telephone interview about demographics, health history, water consumption, and other exposures and provided a semen sample. Semen outcomes included sperm concentration and morphology, as well as DNA integrity and chromatin maturity. Exposures to DBPs were evaluated by incorporating data on water consumption and bathing and showering with concentrations measured in tap water. We used multivariable linear regression to assess the relationship between exposure to DBPs and adverse sperm outcomes. Results The mean (median) sperm concentration and sperm count were 114.2 (90.5) million/mL and 362 (265) million, respectively. The mean (median) of the four trihalomethane species (THM4) exposure was 45.7 (65.3) ?g/L, and the mean (median) of the nine haloacetic acid species (HAA9) exposure was 30.7 (44.2) ?g/L. These sperm parameters were not associated with exposure to these classes of DBPs. For other sperm outcomes, we found no consistent pattern of increased abnormal semen quality with elevated exposure to trihalomethanes (THMs) or haloacetic acids (HAAs). The use of alternate methods for assessing exposure to DBPs and site-specific analyses did not change these results. Conclusions The results of this study do not support an association between exposure to levels of DBPs near or below regulatory limits and adverse sperm outcomes in humans. PMID:17687443

Luben, Thomas J.; Olshan, Andrew F.; Herring, Amy H.; Jeffay, Susan; Strader, Lillian; Buus, Rebecca M.; Chan, Ronna L.; Savitz, David A.; Singer, Philip C.; Weinberg, Howard S.; Perreault, Sally D.

2007-01-01

25

Effects of metabolic rate and sperm competition on the fatty-acid composition of mammalian sperm.  

PubMed

The sperm membrane is a key structure affecting sperm function and thus reproductive success. Spermatozoa are highly specialized and differentiated cells that undergo a long series of processes in the male and female reproductive tracts until they reach the site of fertilization. During this transit, the sperm membrane is prone to damage such as lipid peroxidation. The characteristics and performance of the sperm membrane are strongly determined by the fatty-acid composition of membrane phospholipids. Polyunsaturated fatty-acids (PUFAs) are the most prone to lipid peroxidation. Lipid peroxidation and other types of oxidative damage increase with higher metabolism and with higher levels of sperm competition due to the increased ATP production to fuel higher sperm velocities. Consequently, we hypothesized that, in order to avoid oxidative damage, and the ensuing impairment of sperm function, sperm cells exhibit a negative relationship between PUFA content and mass-specific metabolic rate (MSMR). We also hypothesized that higher sperm competition leads to a reduction in the proportion of sperm PUFAs. We performed a comparative study in mammals and found that high MSMR and high levels of sperm competition both promote a decrease in the proportion of PUFAs that are more prone to lipid peroxidation. The negative relationship between MSMR and these PUFAs in sperm cells is surprising, because a positive relationship is found in all other cell types so far investigated. Our results support the idea that the effects of MSMR and sperm competition on sperm function can operate at very different levels. PMID:24251445

Delbarco-Trillo, J; Roldan, E R S

2013-11-20

26

Increased Sperm DNA Damage in Experimental Rat Varicocele Model and The Beneficial Effect of Varicocelectomy  

PubMed Central

Background Varicocele, the abnormal dilatation of the veins in the pampiniform plexus is commonly seen in infertile patients. In this study, we aim to examine sperm DNA damage after the creation of experimental varicocele in rats and to observe the change of this damage after a varicocelectomy. Materials and Methods In this experimental study, a total of 30 adult male Wistar albino rats were divided into three groups. The 10 rats in group 1 underwent a sham operation, an experimental varicocele was created in both the10 rats in group 2 and the 10 rats in group 3 (a total of 20 rats). While the rats of group 2 were sacrificed after four weeks, the rats in group 3 underwent a varicocelectomy after four weeks and were sacrificed four weeks after the varicocelectomy to observe its effects. Sperm DNA fragmentation was assessed with a Halomax® kit. The DNA Fragmentation Index (DFI) was calculated and the groups were compared according to their DFI. Statistical analysis was performed using the Mann-Whitney U test. Results Median sperm DFI was 17.6 (range: 7.6) in the right testicle and 18.3 (range: 6.8) in the left testicle in the control group; 30.7 (range: 8.8) in the right testicle and 31.8 (range: 9.6) in the left testicle in the varicocele group; 27.1 (range: 8.1) in the right testicle and 28.6 (range: 8.9) in the left testicle in the varicocelectomy group. DNA damage in both right and left testicles was statistically significant between the three groups (p<0.05). Conclusion The results of this study show that varicocele leads to increased sperm DNA damage and this damage is decreased by varicocelectomy. PMID:25493165

Öztürk, Metin ?shak; Koca, Orhan; Kele?, Muzaffer O?uz; Y?lmaz, Seda; Karaman, Muhammet Ihsan

2012-01-01

27

Increasing Productivity at Saturn  

Microsoft Academic Search

To remain competitive, manufacturing enterprises must increase and simultaneously reduce costs. This requires daily and long term examination and analysis of a plant's functions and operations. Using this data, an enterprise can identify production flow bottlenecks and analyze capacity and other factors, which in turn helps identify improvement opportunities. While such information is critical, it is often a challenge to

Earl Long; Amit Misra; Janos Sztipanovits

1998-01-01

28

Individual adjustment of sperm expenditure accords with sperm competition theory  

Microsoft Academic Search

Sperm competition theory predicts that males should strategically allocate their sperm reserves according to the level of sperm competition, defined as the probability that the sperm of two males compete for fertilizing a given set of ova. Substantial evidence from numerous animal taxa suggests that, at the individual level, sperm expenditure increases when the risk of sperm competition is greater.

Andrea Pilastro; Marta Scaggiante; Maria B. Rasotto

2002-01-01

29

Reduced recombination associated with the production of aneuploid sperm in an infertile man: a case report.  

PubMed

Studies using gene-linkage analysis have suggested that abnormal recombination during meiosis may lead to the production of aneuploid gametes; however, there is little direct evidence of a link between the two in human males. We analysed spermatocytes in the pachytene stage from a man with extremely high aneuploidy rates in his sperm. Testicular tissue specimens of the infertile man and two vasectomy reversals were processed with immuofluorescent techniques to visualize synaptonemal complex and recombination foci and fluorescent in situ hybridization on spermatocytes and sperm with probes for chromosomes 13, 21, 18, X and Y. We observed no recombination between sex chromosomes in the infertile man, while in two controls, we observed recombination rates of 79.3 and 81.0% between the sex chromosomes. This was associated with a total sex aneuploidy rate of 41.61% in testicular sperm of the infertile man (0.44 and 0.62% in two controls). Recombination on chromosome 21 was reduced in the infertile man, with 10.62% of spermatocytes showing no recombination (0 and 1.67% in two controls), as well as chromosome 13, with 53.98% having < or =1 recombination foci (22.05 and 21.67% in two controls). This was associated with increased aneuploidy for those chromosomes. Chromosome 18 aneuploidy was slightly increased, although there was no apparent decrease in recombination. These results provide the first evidence of both recombination and non-disjunction abnormalities in the same individual. This is also the only reported case of an infertile man who shows no recombination between the sex chromosomes, despite the formation of the sex body. PMID:16373411

Ma, S; Ferguson, K A; Arsovska, S; Moens, P; Chow, V

2006-04-01

30

Proenkephalin products are stored in the sperm acrosome and may function in fertilization.  

PubMed Central

Previous studies have shown that spermatogenic cells are a major source of testicular RNA encoding the opioid peptide precursor proenkephalin, suggesting that proenkephalin-derived peptides may function as intratesticular paracrine factors produced by male germ cells. However, direct evidence for the production of proenkephalin by spermatogenic cells has been lacking. In this report, we have used polysome profile analysis, peptide quantitation, and immunocytochemistry to show that proenkephalin products are synthesized during spermatogenesis and are retained within spermatozoa of humans, hamsters, rats, and sheep. We further show that these peptides are stored in the sperm acrosome and are depleted from sperm following the acrosome reaction, an exocytotic event required for fertilization. Proenkephalin products thus may serve a dual function as sperm acrosomal factors released during the fertilization process as well as intratesticular regulators secreted by spermatogenic cells. Images PMID:1701253

Kew, D; Muffly, K E; Kilpatrick, D L

1990-01-01

31

Role of increased male age in IVF and egg donation: is sperm DNA fragmentation responsible?  

PubMed

The well documented increase in age that women conceive their first child has detracted from a similar change observed in males. As both males and females decide to conceive later, the question of whether this may impact their fertility individually and as a couple becomes even more crucial. A paternal age of over 40 years at the time of conception is a frequently quoted male age threshold, however, currently there is no clearly accepted definition of advanced paternal age or even a consensus on the implications of advancing male age. In this paper, we review some of the potential risks to the offspring of advancing male age and examine. The data available regarding pregnancy outcomes based on paternal age in both the fertile and infertile populations. Within the infertile population specifically, we examine the association between male age and outcomes based on treatment modality, including intrauterine insemination (IUI), in vitro fertilization (IVF), and donor oocyte IVF. Finally, we discuss the various mechanisms by which male age may impact sperm and fertility potential, including sperm DNA damage. PMID:23273987

Humm, Kathryn C; Sakkas, Denny

2013-01-01

32

Sperm competition and the evolution of sperm design in mammals  

Microsoft Academic Search

BACKGROUND: The influence of sperm competition upon sperm size has been a controversial issue during the last 20 years which remains unresolved for mammals. The hypothesis that, when ejaculates compete with rival males, an increase in sperm size would make sperm more competitive because it would increase sperm swimming speed, has generated contradictory results from both theoretical and empirical studies.

Maximiliano Tourmente; Montserrat Gomendio; Eduardo RS Roldan

2011-01-01

33

Zebrafish Reproduction: Revisiting In Vitro Fertilization to Increase Sperm Cryopreservation Success  

PubMed Central

Although conventional cryopreservation is a proven method for long-term, safe storage of genetic material, protocols used by the zebrafish community are not standardized and yield inconsistent results, thereby putting the security of many genotypes in individual laboratories and stock centers at risk. An important challenge for a successful zebrafish sperm cryopreservation program is the large variability in the post-thaw in vitro fertilization success (0 to 80%). But how much of this variability was due to the reproductive traits of the in vitro fertilization process, and not due to the cryopreservation process? These experiments only assessed the in vitro process with fresh sperm, but yielded the basic metrics needed for successful in vitro fertilization using cryopreserved sperm, as well. We analyzed the reproductive traits for zebrafish males with a strict body condition range. It did not correlate with sperm volume, or motility (P>0.05), but it did correlate with sperm concentration. Younger males produced more concentrated sperm (P<0.05). To minimize the wastage of sperm during the in vitro fertilization process, 106 cells/ml was the minimum sperm concentration needed to achieve an in vitro fertilization success of ? 70%. During the in vitro process, pooling sperm did not reduce fertilization success (P>0.05), but pooling eggs reduced it by approximately 30 to 50% (P<0.05). This reduction in fertilization success was due not to the pooling of the females' eggs, but to the type of tools used to handle the eggs. Recommendations to enhance the in vitro process for zebrafish include: 1) using males of a body condition closer to 1.5 for maximal sperm concentration; 2) minimizing sperm wastage by using a working sperm concentration of 106 motile cells/ml for in vitro fertilization; and 3) never using metal or sharp-edged tools to handle eggs prior to fertilization. PMID:21698162

Hagedorn, Mary; Carter, Virginia L.

2011-01-01

34

Sperm competition, male prudence, and sperm-limited females (2002)  

Microsoft Academic Search

Sperm are produced in astronomical numbers compared with eggs, and there is good evidence that sperm competition is the force behind the evolution of many tiny sperm. However, sperm production inevitably has costs. Recent research shows that male ejaculate expenditure is dynamic in both time and space, and that males are sensitive to risks of sperm competition and can vary

Nina Wedell; Matthew Gage; Geoffrey Parker

35

Gamete Therapeutics: Recombinant Protein Adsorption by Sperm for Increasing Fertility via Artificial Insemination  

PubMed Central

A decrease in fertility can have a negative economic impact, both locally and over a broader geographical scope, and this is especially the case with regard to the cattle industry. Therefore, much interest exists in evaluating proteins that might be able to increase the fertility of sperm. Heparin binding proteins (HBPs), specifically the fertility associated antigen (FAA) and the Type-2 tissue inhibitor of metalloproteinase (TIMP-2), act to favor the capacitation and acrosome reaction and perhaps even modulate the immune system’s response toward the sperm. The objective of this research was to determine the effect on fertility of adding recombinant FAA (rFAA) and recombinant TIMP-2 (rTIMP-2) to bovine semen before cryopreservation for use in an artificial insemination (AI) program in a tropical environment. For this experiment, 100 crossbred (Bos taurus x Bos indicus) heifers were selected based on their estrus cycle, body condition score (BCS), of 4 to 6 on a scale of 1 to 9, and adequate anatomical conformation evaluated by pelvic and genital (normal) measurements. Heifers were synchronized using estradiol benzoate (EB), Celosil® (PGF2?) (Shering-Plough) and a controlled internal drug release (CIDR) device was inserted that contained progesterone. Inseminations were performed in two groups at random, 50 animals per group. The control group was inseminated with conventional semen. The treatment group was inseminated with semen containing rFAA (25 µg/mL) and rTIMP-2 (25 µg/mL). In the control group a 16% pregnancy rate was obtained versus a 40% pregnancy rate for the HBP treatment group, resulting in a significant difference (P?=?0.0037). Given the results herein, one may conclude that the HBPs can increase fertility and could be an option for cattle in tropical conditions; however, one needs to consider the environment, nutrition, and the genetic interaction affecting the final result in whatever reproductive program that is implemented. PMID:23762288

Alvarez-Gallardo, Horacio; Kjelland, Michael E.; Moreno, Juan F.; Welsh, Thomas H.; Randel, Ronald D.; Lammoglia, Miguel A.; Pérez-Martínez, Mario; Lara-Sagahón, Alma V.; Esperón-Sumano, A. Enrique; Romo, Salvador

2013-01-01

36

SIGNIFICANCE OF INCORPORATING MEASURES OF SPERM PRODUCTION AND FUNCTION INTO RAT TOXICOLOGY STUDIES  

EPA Science Inventory

The rat is the preferred species for reproductive toxicity testing. The inclusion of measures of rat sperm quality, such as motility and morphology, into reproductive test protocols often increases the sensitivity of the test to detect effects, and provides the toxicologist and ...

37

Variation in paternity in the field cricket Teleogryllus oceanicus: no detectable influence of sperm numbers or sperm length  

Microsoft Academic Search

Recent attention has focused on the role that sperm competition may play in the evolution of sperm morphology. Theoretical analyses predict increased sperm size, decreased sperm size, and no change in sperm size in response to sperm competition, depending on the assumptions made concerning the life history and function of sperm. However, although there is good evidence that sperm morphology

Leigh W. Simmons; Julie Wernham; Francisco Garci´a-Gonza´lez; Dan Kamien

2003-01-01

38

Sperm production and quality in brill Scophthalmus rhombus L.: relation to circulating sex steroid levels.  

PubMed

The aims of the present study were to characterize sperm quality and to quantify seasonal changes in sexual hormone (testosterone [T], 11-ketotestosterone [11-KT] and 17,20?-dihydroxypregn-4-en-3-one [17,20?-P]) levels in male brill (Scophthalmus rhombus) plasma, as well as to test a more intensive sampling strategy to establish relationships between sex steroid levels and sperm production parameters. Sperm concentration ranged from 0.5 to 3.1 × 10(9) spermatozoa mL(-1), and changes in sperm quality parameters depending on sampling date were observed. Plasma sexual steroid levels remained high and changed in parallel during the spawning season and afterwards decreased to very low levels in summer. The analysis of annual changes of 11-KT and T ratios suggests that 11-KT can be the main circulating androgen for stimulating spermatogenesis in S. rhombus and that T could be involved in the beginning of spermatogenesis through the positive feedback on brain-pituitary-gonad axis. Finally, daily 11-KT and T levels showed similar patterns of variation in males sampled, whereas 17,20?-P amounts showed somewhat opposite trends. These differences could be related with the different role of androgens and progestin during the spermatogenesis. PMID:22806610

Hachero-Cruzado, Ismael; Forniés, Asunción; Herrera, Marcelino; Mancera, Juan Miguel; Martínez-Rodríguez, Gonzalo

2013-04-01

39

Effects of dietary energy on scrotal surface temperature, seminal quality, and sperm production in young beef bulls.  

PubMed

The objective of this study was to determine the effect of dietary energy, breed (British vs Continental x British crosses), and their interactions on scrotal surface temperature (SST), seminal quality, and sperm production in bulls. This experiment, replicated over 2 yr, included 72 Angus, Angus x Simmental, or Hereford x Simmental bulls fed either a moderate- (100% forage) or high-energy (80% grain, 20% forage) diet for 168 d after weaning. At the end of the feeding period, SST was determined by infrared thermography, seminal samples (two ejaculates) were collected by electroejaculation, and reproductive tracts were collected at slaughter. Bulls fed the high-energy diet were heavier (P < .0001; diet x time interaction), had thicker backfat (P < .05; diet x line x time interaction), and had a larger scrotal circumference (P < .05). Testicular tone decreased over time (P < .0001) with a diet x time interaction (P < .05). There was no significant effect of diet on top, bottom, or average SST. However, bulls fed the moderate-energy diet had a larger (P < .02) SST gradient (3.9 vs. 3.4 degrees C). Bulls fed the moderate-energy diet had more (P < .01) morphologically normal spermatozoa (68.8 +/- 2.1 vs 62.5 +/- 2.5%) and a higher proportion (P < .006) of progressively motile spermatozoa (53.4 +/- 2.1 vs 44.5 +/- 2.4%). No effects (P > .05) of dietary energy on epididymal sperm reserves or daily sperm production were detected. Increased dietary energy may affect scrotal or testicular thermoregulation by reducing the amount of heat that can be radiated from the scrotal neck, thereby increasing the temperature of the testes and scrotum. PMID:9110219

Coulter, G H; Cook, R B; Kastelic, J P

1997-04-01

40

A Sustained Increase in Intracellular Ca 2+ Is Required for the Acrosome Reaction in Sea Urchin Sperm  

Microsoft Academic Search

The acrosome reaction (AR), necessary for fertilization in many species, requires an increase in intracellular Ca2+ ([Ca2+]i). In sea urchin sperm, the AR is triggered by an egg-jelly factor: the associated [Ca2+]i elevation lasts minutes and involves two Ca2+ permeable channels. Both the opening of the second channel and the onset of the AR occur ?5 s after treatment with

Marco T. González-Martínez; Blanca E. Galindo; Lucia de De La Torre; Otilia Zapata; Esmeralda Rodríguez; Harvey M. Florman; Alberto Darszon

2001-01-01

41

Male capacity as related to sperm production, pregnancy initiation, and sperm competition in deer mice ( Peromyscus maniculatus )  

Microsoft Academic Search

Limitations on male capacity may be important to the evolution of mating strategies and behavior. Sperm counts in successive ejaculates of deer mice (Peromyscus maniculatus) decreased progressively through six ejaculations and remained depressed the following day. Males were as effective in inseminating females in cycling estrus with their second two ejaculates as with their first two and as effective in

Donald A. Dewsbury; D. Kim Sawrey

1984-01-01

42

Sperm competition and the evolution of sperm design in mammals  

PubMed Central

Background The influence of sperm competition upon sperm size has been a controversial issue during the last 20 years which remains unresolved for mammals. The hypothesis that, when ejaculates compete with rival males, an increase in sperm size would make sperm more competitive because it would increase sperm swimming speed, has generated contradictory results from both theoretical and empirical studies. In addition, the debate has extended to which sperm components should increase in size: the midpiece to accommodate more mitochondria and produce more energy to fuel motility, or the principal piece to generate greater propulsion forces. Results In this study we examined the influence of sperm competition upon sperm design in mammals using a much larger data set (226 species) than in previous analyses, and we corrected for phylogenetic effects by using a more complete and resolved phylogeny, and more robust phylogenetic control methods. Our results show that, as sperm competition increases, all sperm components increase in an integrated manner and sperm heads become more elongated. The increase in sperm length was found to be associated with enhanced swimming velocity, an adaptive trait under sperm competition. Conclusions We conclude that sperm competition has played an important role in the evolution of sperm design in mammals, and discuss why previous studies have failed to detect it. PMID:21232104

2011-01-01

43

Daily production of spermatophores, sperm number and spermatophore size in two eriophyoid mite species.  

PubMed

Under dissociated sperm transfer, (non-pairing) males deposit spermatophores on a substrate, while females seek spermatophores and pick up sperm on their own. Spermatophore expenditures of non-pairing males should be high, due to the increased uncertainty of sperm uptake by a female. In this study I examined spermatophore expenditures in two eriophyoid species that differed in the degree of dissociation between sexes: (1) Aculus fockeui (Nalepa and Trouessart) males rarely visit quiescent female nymphs (QFNs), and mostly deposit spermatophores all over the leaves, whereas (2) Aculops allotrichus (Nalepa) males guard QFNs for many hours and deposit several spermatophores beside them. Males of both species were collected from the field and tested in solitude. Aculus fockeui males deposited on average 19.1 spermatophores per day, whereas A. allotrichus deposited only 3.6 spermatophores per day, and had a very large coefficient of variation. Males and spermatophores of A. allotrichus were significantly smaller and contained less sperm than those of A. fockeui. In both eriophyoids, spermatophore size was fitted to the size of female genitalia and the height of females. The ratio between the diameter of spermatophore head and the width of a female genital coverflap was 0.6, whereas the ratio between the female leg and the length of spermatophore stalk was 0.5. Several factors could be responsible for the discrepancy in spermatophore expenditures between species. Among other factors, the effects of male size, male reproductive strategy and female genitalia size on spermatophore output and size of spermatophores are discussed. PMID:21751036

Michalska, Katarzyna

2011-12-01

44

Surrogate Production of Eggs and Sperm by Intrapapillary Transplantation of Germ Cells in Cytoablated Adult Fish  

PubMed Central

Germ cell transplantation (GCT) is a promising assisted reproductive technology for the conservation and propagation of endangered and valuable genetic resources. In teleost fish, GCT in adult gonads has been achieved only in male recipients, limiting greatly the usefulness of this technique in situations where both sexes need equal and timely attention for conservation and/or propagation. Here we describe a simplified GCT approach that ultimately leads to production of donor-derived eggs and sperm in considerably short time. Donor germ cells isolated from young pejerrey Odontesthes bonariensis (Atherinopsidae) were transplanted non-surgically through the genital papilla into the sexually mature gonads of Patagonian pejerrey O. hatcheri recipients whose gonads have been depleted of endogenous GCs by heat (26°C) and chemical treatment (four doses of Busulfan at 30 mg/kg and 40 mg/kg for females and males, respectively). Transplanted spermatogonial and oogonial cells were able to recolonize the recipients' gonads and produce functional donor origin eggs and sperm within 7 months from the GCT. We confirmed the presence of donor-derived gametes by PCR in 17% and 5% of the surrogate O. hatcheri fathers and mothers, respectively. The crosses between surrogate fathers and O. bonariensis mothers yielded 12.6–39.7% pure O. bonariensis and that between a surrogate mother and an O. bonariensis father yielded 52.2% pure O. bonariensis offspring. Our findings confirm that transplantation of germ cells into sexually competent adult fish by non-surgical methods allows the production of functional donor-derived eggs and sperm in a considerably short time. The methods described here could play a vital role in conservation and rapid propagation of endangered fish genetic resources. PMID:24748387

Majhi, Sullip Kumar; Hattori, Ricardo Shohei; Rahman, Sheikh Mustafizur; Strüssmann, Carlos Augusto

2014-01-01

45

Why mammalian lineages respond differently to sexual selection: metabolic rate constrains the evolution of sperm size  

PubMed Central

The hypothesis that sperm competition should favour increases in sperm size, because it results in faster swimming speeds, has received support from studies on many taxa, but remains contentious for mammals. We suggest that this may be because mammalian lineages respond differently to sexual selection, owing to major differences in body size, which are associated with differences in mass-specific metabolic rate. Recent evidence suggests that cellular metabolic rate also scales with body size, so that small mammals have cells that process energy and resources from the environment at a faster rate. We develop the ‘metabolic rate constraint hypothesis’ which proposes that low mass-specific metabolic rate among large mammals may limit their ability to respond to sexual selection by increasing sperm size, while this constraint does not exist among small mammals. Here we show that among rodents, which have high mass-specific metabolic rates, sperm size increases under sperm competition, reaching the longest sperm sizes found in eutherian mammals. By contrast, mammalian lineages with large body sizes have small sperm, and while metabolic rate (corrected for body size) influences sperm size, sperm competition levels do not. When all eutherian mammals are analysed jointly, our results suggest that as mass-specific metabolic rate increases, so does maximum sperm size. In addition, species with low mass-specific metabolic rates produce uniformly small sperm, while species with high mass-specific metabolic rates produce a wide range of sperm sizes. These findings support the hypothesis that mass-specific metabolic rates determine the budget available for sperm production: at high levels, sperm size increases in response to sexual selection, while low levels constrain the ability to respond to sexual selection by increasing sperm size. Thus, adaptive and costly traits, such as sperm size, may only evolve under sexual selection when metabolic rate does not constrain cellular budgets. PMID:21389027

Gomendio, Montserrat; Tourmente, Maximiliano; Roldan, Eduardo R. S.

2011-01-01

46

Comparative evidence for the evolution of sperm swimming speed by sperm competition and female sperm storage duration in passerine birds.  

PubMed

Sperm swimming speed is an important determinant of male fertility and sperm competitiveness. Despite its fundamental biological importance, the underlying evolutionary processes affecting this male reproductive trait are poorly understood. Using a comparative approach in a phylogenetic framework, we tested the predictions that sperm swim faster with (1) increased risk of sperm competition, (2) shorter duration of female sperm storage, and (3) increased sperm length. We recorded sperm swimming speed in 42 North American and European free-living passerine bird species, representing 35 genera and 16 families. We found that sperm swimming speed was positively related to the frequency of extrapair paternity (a proxy for the risk of sperm competition) and negatively associated with clutch size (a proxy for the duration of female sperm storage). Sperm swimming speed was unrelated to sperm length, although sperm length also increased with the frequency of extrapair paternity. These results suggest that sperm swimming speed and sperm length are not closely associated traits and evolve independently in response to sperm competition in passerine birds. Our findings emphasize the significance of both sperm competition and female sperm storage duration as evolutionary forces driving sperm swimming speed. PMID:19453726

Kleven, Oddmund; Fossøy, Frode; Laskemoen, Terje; Robertson, Raleigh J; Rudolfsen, Geir; Lifjeld, Jan T

2009-09-01

47

Competition Between the Sperm of a Single Male Can Increase the Evolutionary Rate of Haploid Expressed Genes  

PubMed Central

The population genetic behavior of mutations in sperm genes is theoretically investigated. We modeled the processes at two levels. One is the standard population genetic process, in which the population allele frequencies change generation by generation, depending on the difference in selective advantages. The other is the sperm competition during each genetic transmission from one generation to the next generation. For the sperm competition process, we formulate the situation where a huge number of sperm with alleles A and B, produced by a single heterozygous male, compete to fertilize a single egg. This “minimal model” demonstrates that a very slight difference in sperm performance amounts to quite a large difference between the alleles’ winning probabilities. By incorporating this effect of paternity-sharing sperm competition into the standard population genetic process, we show that fierce sperm competition can enhance the fixation probability of a mutation with a very small phenotypic effect at the single-sperm level, suggesting a contribution of sperm competition to rapid amino acid substitutions in haploid-expressed sperm genes. Considering recent genome-wide demonstrations that a substantial fraction of the mammalian sperm genes are haploid expressed, our model could provide a potential explanation of rapid evolution of sperm genes with a wide variety of functions (as long as they are expressed in the haploid phase). Another advantage of our model is that it is applicable to a wide range of species, irrespective of whether the species is externally fertilizing, polygamous, or monogamous. The theoretical result was applied to mammalian data to estimate the selection intensity on nonsynonymous mutations in sperm genes. PMID:23666936

Ezawa, Kiyoshi; Innan, Hideki

2013-01-01

48

Job stress and productivity increase.  

PubMed

This paper examines mental and physical pressures that workers bear at work. The authors discuss how on the-job stress affects a person's capabilities and productivity, and how such pressures lend to higher incidences of accidents at work. The paper also discuss methods of reducing job-related stress and increasing productivity. An intervention was conducted amongst workers in a private firm. It shows mental and emotional pressure can affect performance and productivity of a worker on the job. One of the biggest influences of today's worker is on the-job stress. Job stress occurs when the requirements of the job do not match the capabilities, resources, or needs of the worker. This consequently affects how a person would normally deal with customer service problems, grievances, violence, conflict, and decisions on the job. Stress is an inevitable part of everyday life, and is therefore a distinct part of a person's job. To properly control the outcome of stress, there are certain precautions and methods that should be taken that will boost productivity. PMID:22317168

Adaramola, Samson Sunday

2012-01-01

49

Procurement of exogenous ammonia by the swallowtail butterfly, Papilio polytes, for protein biosynthesis and sperm production  

NASA Astrophysics Data System (ADS)

How to acquire sufficient quantity of nitrogen is a pivotal issue for herbivores, particularly for lepidopterans (butterflies and moths) of which diet quality greatly differs among their life stages. Male Lepidoptera often feed from mud puddles, dung, and carrion, a behavior known as puddling, which is thought to be supplementary feeding targeted chiefly at sodium. During copulation, males transfer a spermatophore to females that contains, besides sperm, nutrients (nuptial gifts) rich in sodium, proteins, and amino acids. However, it is still poorly understood how adults, mostly nectarivores, extract nitrogen from the environment. We examined the availability of two ubiquitous inorganic nitrogenous ions in nature, viz. ammonium (or ammonia) and nitrate ions, as nutrients in a butterfly, and show that exogenous ammonia ingested by adult males of the swallowtail, Papilio polytes, can serve as a resource for protein biosynthesis. Feeding experiments with 15N-labeled ammonium chloride revealed that nitrogen was incorporated into eupyrene spermatozoa, seminal protein, and thoracic muscle. Ammonia uptake by males significantly increased the number of eupyrene sperms in the reproductive tract tissues. The females also had the capacity to assimilate ammonia into egg protein. Consequently, it is evident that acquired ammonia is utilized for the replenishment of proteins allocable for reproduction and somatic maintenance. The active exploitation of exogenous ammonia as a nutrient by a butterfly would foster better understanding of the foraging and reproductive strategies in insects.

Honda, Keiichi; Takase, Hiroyuki; Ômura, Hisashi; Honda, Hiroshi

2012-09-01

50

Testicular development, daily sperm production and epididymal sperm reserves in 15-mo-old Angus and Hereford bulls: effects of bull strain plus dietary energy.  

PubMed

Bull calves (n = 143) were obtained from two strains of Angus and two strains of Hereford cattle for which replacements were selected on the basis of superior feedlot growth performance on either high- or medium-energy diets. From weaning to slaughter at 15 mo of age, bulls were fed either the high-energy (80% grain + 20% forage) or medium-energy diet (100% forage) corresponding to their strain. Bulls in high-energy diet groups had a greater (P less than .05) scrotal circumference at 12 mo, but not 15 mo of age, than bulls in medium-energy diet groups. Compared with Hereford bulls, Angus had greater (P less than .01) scrotal circumference (36.1 vs 33.9 cm) and greater (P less than .05) paired testes weight (570 vs 464 g) at 15 mo of age. Daily sperm production per gram testicular parenchyma (DSP/g) was affected by strain-diet (P less than .01) but not by breed. Bulls in medium-energy diet groups had 12% greater DSP/g than did high-energy diet bulls (17.4 X 10(6) vs 15.5 X 10(6)). Daily sperm production (DSP) was 9% and 30% greater (P less than .01) for medium-energy diet bulls in 1980 (8.2 X 10(9) vs 7.5 X 10(9)) and 1981 (8.0 X 10(9) vs 6.2 X 10(9)), respectively, compared with high-energy diet bulls. The effect (P less than .01) of breed on DSP was attributed to breed differences in paired testes weight.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3818488

Coulter, G H; Carruthers, T D; Amann, R P; Kozub, G C

1987-01-01

51

An Extract of Pomegranate Fruit and Galangal Rhizome Increases the Numbers of Motile Sperm: A Prospective, Randomised, Controlled, Double-Blinded Trial  

PubMed Central

Pomegranate fruit (Punica granatum) and galangal (Alpinia galanga) have separately been shown to stimulate spermatogenesis and to increase sperm counts and motility in rodents. Within traditional medicine, pomegranate fruit has long been used to increase fertility, however studies on the effect on spermatogenesis in humans have never been published. With this study we investigated whether oral intake of tablets containing standardised amounts of extract of pomegranate fruit and powder of greater galangal rhizome (Punalpin) would increase the total number of motile spermatozoa. The study was designed as a prospective, randomized, controlled, double-blinded trial. Enrolment was based on the mean total number of motile spermatozoa of two ejaculates. The participants delivered an ejaculate after 4–8 days of tablet intake and two ejaculates just before they stopped taking the tablets. Seventy adult men with a semen quality not meeting the standards for commercial application at Nordic Cryobank, but without azoospermia, were included in the study. Participants were randomized to take tablets containing extract of pomegranate fruit (standardised with respect to punicalagin A+B, punicalin and ellagic acid) and freeze-dried rhizome of greater galangal (standardised with respect to 1?S-1?-acetoxychavicol acetate) or placebo on a daily basis for three months. Sixty-six participants completed the intervention (active treatment: n?=?34; placebo: n?=?32). After the intervention the total number of motile spermatozoa was increased in participants treated with plant extracts compared with the placebo group (p?=?0.026). After three months of active treatment, the average total number of motile sperm increased by 62% (from 23.4 to 37.8 millions), while for the placebo group, the number of motile sperm increased by 20%. Sperm morphology was not affected by the treatment. Our findings may help subfertile men to gain an improved amount of motile ejaculated sperm by taking tablets containing preparations of pomegranate fruit extract and rhizome of greater galangal. Trial Registration ClinicalTrials.gov NCT01357044 PMID:25275520

Fedder, Maja D. K.; Jakobsen, Henrik B.; Giversen, Ina; Christensen, Lars P.; Parner, Erik T.; Fedder, Jens

2014-01-01

52

A Quality Assurance Initiative for Commercial-Scale Production in High-Throughput Cryopreservation of Blue Catfish Sperm  

PubMed Central

Cryopreservation of fish sperm has been studied for decades at a laboratory (research) scale. However, high-throughput cryopreservation of fish sperm has recently been developed to enable industrial-scale production. This study treated blue catfish (Ictalurus furcatus) sperm high-throughput cryopreservation as a manufacturing production line and initiated quality assurance plan development. The main objectives were to identify: 1) the main production quality characteristics; 2) the process features for quality assurance; 3) the internal quality characteristics and their specification designs; 4) the quality control and process capability evaluation methods, and 5) the directions for further improvements and applications. The essential product quality characteristics were identified as fertility-related characteristics. Specification design which established the tolerance levels according to demand and process constraints was performed based on these quality characteristics. Meanwhile, to ensure integrity throughout the process, internal quality characteristics (characteristics at each quality control point within process) that could affect fertility-related quality characteristics were defined with specifications. Due to the process feature of 100% inspection (quality inspection of every fish), a specific calculation method, use of cumulative sum (CUSUM) control charts, was applied to monitor each quality characteristic. An index of overall process evaluation, process capacity, was analyzed based on in-control process and the designed specifications, which further integrates the quality assurance plan. With the established quality assurance plan, the process could operate stably and quality of products would be reliable. PMID:23872356

Hu, E; Liao, T. W.; Tiersch, T. R.

2013-01-01

53

Intracellular calcium increases with hyperactivation in intact, moving hamster sperm and oscillates with the flagellar beat cycle.  

PubMed

At some time before fertilization, mammalian sperm undergo a change in movement pattern, termed hyperactivation. There is evidence that hyperactivation offers an advantage to sperm for detaching from the oviductal mucosa, for penetrating viscoelastic substances in the oviduct, and for penetrating the zona pellucida. Hyperactivation is known to require extracellular calcium, but little else is known about the mechanisms by which calcium affects sperm movement. The calcium-sensitive fluorescent dye indo-1 was used to follow intracellular calcium levels ([Ca2+]i) in individual moving sperm. Sperm were loaded with 10 microM of the acetoxymethyl ester form of the dye and then rinsed. The dye was excited at 340 nm by using a filtered xenon stroboscope, and images at the 405-nm and 490-nm excitation maxima were simultaneously digitized at 30 per sec for 2.1 sec. [Ca2+]i was significantly higher in the acrosomal and postacrosomal regions of the head and in the flagellar midpiece (the principal piece could not be measured) in hyperactivated than in nonhyperactivated sperm (P < 0.0001). [Ca2+]i oscillations were detected in the proximal half of the midpiece that were identical in frequency to the flagellar-beat-cycle frequency in 12 of 17 hyperactivated sperm (median, 3.5 Hz). Rapid [Ca2+]i oscillations were also detected in the acrosomal and postacrosomal regions, as well as in the distal midpiece. Oscillations were not eliminated by dampening the flagellar bending with methyl cellulose. The [Ca2+]i oscillations detected in sperm are significantly more rapid than oscillations detected in other cell types. PMID:8506314

Suarez, S S; Varosi, S M; Dai, X

1993-05-15

54

Accelerated aging of reproductive capacity in male rat offspring of protein-restricted mothers is associated with increased testicular and sperm oxidative stress.  

PubMed

Maternal protein restriction (MPR) in pregnancy causes life course organ dysfunction, but few studies link the developmental origins of disease hypothesis to early aging. Suboptimal developmental nutrition increases oxidative stress (OS) and male infertility, damaging sperm function. We hypothesized that MPR in pregnancy accelerates age-related changes in testicular and sperm function related to both maternal diet and increased testicular OS in rat offspring. We studied male rats whose pregnant mothers ate either control (C, 20 % casein) or restricted (R, 10 % casein) isocaloric diet. After birth, mothers and offspring ate C diet. Testes were retrieved at 19 days gestation and across the life course (postnatal day (PND) 21, 36, 110, and 850) to measure OS markers, antioxidant enzymes, serum FSH, LH, and testosterone, and PND 110 sperm OS and quality. Fertility rate was evaluated at PND 110, 450, and 850. Offspring showed age- and MPR-related changes in testosterone, testicular OS markers and antioxidant enzymes and fertility, and maternal diet-related OS and sperm antioxidant enzyme changes. Developmental programming is considered a key factor in predisposing to chronic disease. Our data show that programming also plays an important role in aging trajectory. This interaction is a little studied area in aging biology that merits more investigation. PMID:25354645

Rodríguez-González, Guadalupe L; Reyes-Castro, Luis A; Vega, Claudia C; Boeck, Lourdes; Ibáñez, Carlos; Nathanielsz, Peter W; Larrea, Fernando; Zambrano, Elena

2014-12-01

55

Cryotolerance of stallion spermatozoa is related to ROS production and mitochondrial membrane potential rather than to the integrity of sperm nucleus.  

PubMed

Although cryopreservation of stallion spermatozoa allows long-term preservation of spermatozoa from particular stallions and facilitates international trade, it is understood to inflict damages on sperm cells that may finally reduce their fertilizing ability. In addition, individual differences are known to exist in the sperm ability to withstand freeze-thawing protocols. To date, these differences have mainly been reported on the basis of sperm motility and membrane integrity. For this reason, the present work sought to determine differences between good (good freezability ejaculates: GFE) and poor (poor freezability ejaculates: PFE) freezability stallion ejaculates in other sperm parameters, including peroxide and superoxide levels, potential of mitochondrial membrane and nuclear integrity. With this purpose, a total of 24 stallion ejaculates were cryopreserved and classified into two groups (GFE vs. PFE), depending on their sperm membrane integrity and motility after freeze-thawing. From the total of 24 ejaculates, 13 were classified as GFE and the other 11 were classified as PFE. Apart from differences in sperm membrane permeability and lipid disorder after freeze-thawing, GFE presented significantly (p < 0.05) higher percentages of viable spermatozoa with high content of peroxides and of superoxides than PFE. In contrast, and despite cryopreservation of stallion spermatozoa increasing DNA fragmentation and disrupting disulphide bonds in sperm head proteins, no significant differences between GFE and PFE were seen. We can thus conclude that good and poor freezability stallion ejaculates differ in their reactive oxygen species levels after cryopreservation, but not in the damage extent on sperm nucleus. PMID:25294093

Yeste, M; Estrada, E; Rocha, L G; Marín, H; Rodríguez-Gil, J E; Miró, J

2014-10-01

56

Soluble Products of Escherichia coli Induce Mitochondrial Dysfunction-Related Sperm Membrane Lipid Peroxidation Which Is Prevented by Lactobacilli  

PubMed Central

Unidentified soluble factors secreted by E. coli, a frequently isolated microorganism in genitourinary infections, have been reported to inhibit mitochondrial membrane potential (??m), motility and vitality of human spermatozoa. Here we explore the mechanisms involved in the adverse impact of E. coli on sperm motility, focusing mainly on sperm mitochondrial function and possible membrane damage induced by mitochondrial-generated reactive oxygen species (ROS). Furthermore, as lactobacilli, which dominate the vaginal ecosystem of healthy women, have been shown to exert anti-oxidant protective effects on spermatozoa, we also evaluated whether soluble products from these microorganisms could protect spermatozoa against the effects of E. coli. We assessed motility (by computer-aided semen analysis), ??m (with JC-1 dye by flow cytometry), mitochondrial ROS generation (with MitoSOX red dye by flow cytometry) and membrane lipid-peroxidation (with the fluorophore BODIPY C11 by flow cytometry) of sperm suspensions exposed to E. coli in the presence and in the absence of a combination of 3 selected strains of lactobacilli (L. brevis, L. salivarius, L. plantarum). A Transwell system was used to avoid direct contact between spermatozoa and microorganisms. Soluble products of E. coli induced ??m loss, mitochondrial generation of ROS and membrane lipid-peroxidation, resulting in motility loss. Soluble factors of lactobacilli prevented membrane lipid-peroxidation of E. coli-exposed spermatozoa, thus preserving their motility. In conclusion, sperm motility loss by soluble products of E. coli reflects a mitochondrial dysfunction-related membrane lipid-peroxidation. Lactobacilli could protect spermatozoa in the presence of vaginal disorders, by preventing ROS-induced membrane damage. PMID:24358256

Barbonetti, Arcangelo; Vassallo, Maria Rosaria Caterina; Cinque, Benedetta; Filipponi, Silvia; Mastromarino, Paola; Cifone, Maria Grazia; Francavilla, Sandro; Francavilla, Felice

2013-01-01

57

Sperm swimming speed and energetics vary with sperm competition risk in bluegill ( Lepomis macrochirus )  

Microsoft Academic Search

Under sperm competition, a male’s fertilization success depends largely on the ejaculate characteristics of competing males. Theoretical models predict that, in external fertilizers, increased risk of sperm competition should result in selection for increased sperm swimming speed. To test this prediction, we studied the behavior of sperm from parental and sneaker male bluegill ( Lepomis macrochirus), a fish species characterized

Gary Burness; Stephen J. Casselman; Albrecht I. Schulte-Hostedde; Christopher D. Moyes; Robert Montgomerie

2004-01-01

58

Lipid Peroxidation and Nitric Oxide Levels in Male Smokers' Spermatozoa and their Relation with Sperm Motility  

PubMed Central

Background Nitric oxide (NO) is synthesized from L-arginine by a family of enzymes known as nitric oxide synthases. Low concentrations of NO is essential in biology and physiology of spermatozoa, but high amounts of NO is toxic and has negative effects on sperm functions. Moreover, sperm membrane contains high concentrations of polyunsaturated fatty acids that are highly susceptible to oxidative damage that interferes with fertilization ability. Therefore, we investigated the correlation between levels of sperm malondialdehyde (MDA) and NO with sperm motility in male smokers. Methods Semen samples were collected from normozoospermic smoker (n=64) and nonsmoker (n=83) men. The content of sperm lipid peroxidation was determined by measuring malondialdehyde (MDA). The sperm NO were also measured using Griess reagent. Data was analyzed by SPSS, (version 15.0), using independent t-test and Pearson analysis. Results The mean MDA and NO concentrations in the sperm of normozoospermic male smokers were significantly higher than the control group or normozoospermic nonsmokers, (p <0.001). A significant negative relationship was noted between sperm motility and sperm MDA levels (r=?0.32, p=0.01); and sperm motility and sperm NO concentration (for nitrite, r=?0.34, p=0.006 and for nitrate, r=?0.38, p=0.002). Conclusion It was concluded that the increase in MDA and NO production in sperm can influence sperm motility in normozoospermic smokers. Therefore, it seems that cigarette smoking may affect the fertility of male smokers via increasing the amount of sperm MDA/lipid peroxidation and NO concentrations. PMID:23926529

Ghaffari, Mohammad Ali; Rostami, Morad

2012-01-01

59

Effect of docosahexaenoic acid and alpha-tocopherol enrichment in chicken sperm on semen quality, sperm lipid composition and susceptibility to peroxidation.  

PubMed

The aim of the present experiment was to study the effect of fish oil and Vitamin E rich diets on semen production, sperm functions and composition in broiler breeders. The following parameters were measured: semen volume and concentration, sperm motility and viability, sperm susceptibility to induced peroxidation, sperm lipid and alpha-tocopherol contents. Dietary n-3 PUFA were successfully transferred into spermatozoan phospholipid by fish oil feeding according to the following main features: (a) the C22:6n-3 and C22:5n - 3 contents were increased, but C22:4n-6 remained the peculiar and major polyunsaturate; (b) the content and proportion of total PUFA did not change; (c) the proportional increase of n-3 PUFA was compensated by the decrease of n-6 PUFA, an increase in the proportion of n-9 fatty acids was also found. The sperm content of alpha-tocopherol was doubled increasing the dietary availability of the vitamin to 300 mg/kg of feed. The specific n-3 PUFA and Vitamin E enrichment of chicken sperm affected cell functions. Significant interactions between the two treatments were also found for some parameters. The best sperm quality condition in control sperm (rich mainly in n-6 PUFA) was found supplying 200mg Vitamin E/kg of feed to the male breeders, and in contrast in n-3 rich sperm supplying 300 mg Vitamin E/kg. PMID:16530814

Cerolini, S; Zaniboni, L; Maldjian, A; Gliozzi, T

2006-09-01

60

Competition drives cooperation among closely related sperm of deer mice.  

PubMed

Among the extraordinary adaptations driven by sperm competition is the cooperative behaviour of spermatozoa. By forming cooperative groups, sperm can increase their swimming velocity and thereby gain an advantage in intermale sperm competition. Accordingly, selection should favour cooperation of the most closely related sperm to maximize fitness. Here we show that sperm of deer mice (genus Peromyscus) form motile aggregations, then we use this system to test predictions of sperm cooperation. We find that sperm aggregate more often with conspecific than heterospecific sperm, suggesting that individual sperm can discriminate on the basis of genetic relatedness. Next, we provide evidence that the cooperative behaviour of closely related sperm is driven by sperm competition. In a monogamous species lacking sperm competition, Peromyscus polionotus, sperm indiscriminately group with unrelated conspecific sperm. In contrast, in the highly promiscuous deer mouse, Peromyscus maniculatus, sperm are significantly more likely to aggregate with those obtained from the same male than with sperm from an unrelated conspecific donor. Even when we test sperm from sibling males, we continue to see preferential aggregations of related sperm in P. maniculatus. These results suggest that sperm from promiscuous deer mice discriminate among relatives and thereby cooperate with the most closely related sperm, an adaptation likely to have been driven by sperm competition. PMID:20090679

Fisher, Heidi S; Hoekstra, Hopi E

2010-02-11

61

Effects of intratesticular zinc gluconate treatment on testicular dimensions, echodensity, histology, sperm production, and testosterone secretion in American black bears (Ursus americanus).  

PubMed

Eight adult American black bears were used to evaluate the effects of chemical castration by intratesticular zinc gluconate treatment on testicular dimensions, echodensity, histology, sperm production, and testosterone secretion. Treatment did not affect testicular dimensions and did not result in decreased resting or GnRH-stimulated testosterone secretion. Multifocal hyperchoic areas in the testicular parenchyma were observed on ultrasound examination, and white foci were observed on gross pathology examination after zinc gluconate treatment. Histologically, there were normal seminiferous tubules containing either round or elongated spermatids, along with abnormal tubules in all bears after treatment. Vacuolation of the seminiferous epithelium, sloughing of germ cells into the tubules' lumen, presence of multinuclear giant cells, and reduced height of the seminiferous epithelium with missing generations of germ cells were commonly observed. The most severe testicular changes were multifocal and included fibrosis, complete degeneration of the seminiferous epithelium with shrinkage of the tubule, and sperm stasis. Epididymal sperm reserve was 982.74 ± 654.16 × 10(6) sperm (mean ± SEM) and motile sperm were observed in the epididymis of all but one of the bears. In conclusion, although intratesticular zinc gluconate treatment in black bears resulted in testicular degenerative changes detected by ultrasound and histology examinations, sperm production was not completely ablated. We inferred that normal fertility might have been compromised, but treatment unlikely resulted in sterility. PMID:21356548

Brito, Leonardo F C; Sertich, Patricia L; Rives, William; Knobbe, Marc; Del Piero, Fabio; Stull, Gordon B

2011-05-01

62

Sperm competition: linking form to function  

PubMed Central

Background Using information from physics, biomechanics and evolutionary biology, we explore the implications of physical constraints on sperm performance, and review empirical evidence for links between sperm length and sperm competition (where two or more males compete to fertilise a female's eggs). A common theme in the literature on sperm competition is that selection for increased sperm performance in polyandrous species will favour the evolution of longer, and therefore faster swimming, sperm. This argument is based on the common assumption that sperm swimming velocity is directly related to sperm length, due to the increased thrust produced by longer flagella. Results We critically evaluate the evidence for links between sperm morphology and swimming speed, and draw on cross-disciplinary studies to show that the assumption that velocity is directly related to sperm length will rarely be satisfied in the microscopic world in which sperm operate. Conclusion We show that increased sperm length is unlikely to be driven by selection for increased swimming speed, and that the relative lengths of a sperm's constituent parts, rather than their absolute lengths, are likely to be the target of selection. All else being equal, we suggest that a simple measure of the ratio of head to tail length should be used to assess the possible link between morphology and speed. However, this is most likely to be the case for external fertilizers in which females have relatively limited opportunity to influence a sperm's motility. PMID:19032741

2008-01-01

63

Reduced recombination associated with the production of aneuploid sperm in an infertile man: a case report  

Microsoft Academic Search

Studies using gene-linkage analysis have suggested that abnormal recombination during meiosis may lead to the pro- duction of aneuploid gametes; however, there is little direct evidence of a link between the two in human males. We analysed spermatocytes in the pachytene stage from a man with extremely high aneuploidy rates in his sperm. Testic- ular tissue specimens of the infertile

S. Ma; K. A. Ferguson; S. Arsovska; P. Moens; V. Chow; Willow Pavilion

2005-01-01

64

Effect of the knobbed acrosome defect in bovine sperm on IVF and embryo production  

Microsoft Academic Search

An IVF and culture system was used to determine the effect of the knobbed acrosome defect in bovine spermatozoa on fertilization and early embryonic development. Three bulls affected with knobbed acrosomes were identified as K+ (flattened acrosome), K2+ (indented acrosome) or K3+ (deep indentation of the acrosome) based on the predominant type of acrosomal aberration present in sperm of the

J. Thundathil; R. Meyer; A. T. Palasz; A. D. Barth; R. J. Mapletoft

2000-01-01

65

Production of donor-derived sperm after spermatogonial stem cell transplantation in the dog  

PubMed Central

Spermatogonial stem cell transplantation offers unique approaches to investigate spermatogonial stem cells (SSC) and to manipulate the male germline. We report here the first successful performance of this technique in the dog, which is an important model of human diseases. First, we investigated an irradiation protocol to deplete endogenous male germ cells in recipient testes. Histologic examination confirmed >95% depletion of endogenous spermatogenesis, but retention of normal testis architecture. Then, five month-old recipient dogs (n=5) were focally irradiated on their testes prior to transplantation with mixed seminiferous tubule cells [fresh (n=2) or after two weeks of culture (n=3)]. The dogs receiving cultured cells showed an immediate allergic response, which subsided quickly with palliative treatment. No such response was seen in the dogs receiving fresh cells, for which a different injection medium was used. 12 months post injection, recipients were castrated and sperm was collected from epididymides. We performed microsatellite analysis comparing DNA from the epididymal sperm with genomic DNA from both the recipients and the donors. We used 6 markers to demonstrate the presence of donor alleles in the sperm from one recipient of fresh mixed tubule cells. No evidence of donor alleles was detected in sperm from the other recipients. Using quantitative PCR based on single nucleotide polymorphisms, about 19.5% of sperm were shown to be donor-derived in the recipient. Our results demonstrate the first successful completion of SSCT in the dog, an important step toward transgenesis through the male germline in this valuable biomedical model. PMID:18768666

Kim, Yeunhee; Turner, Danielle; Nelson, Jacquelyn; Dobrinski, Ina; McEntee, Margaret; Travis, Alexander J.

2009-01-01

66

Variability in sperm form and function in the context of sperm competition risk in two Tupinambis lizards  

PubMed Central

In polyandrous species, sperm morphometry and sperm velocity are under strong sexual selection. Although several hypotheses have been proposed to explain the role of sperm competition in sperm trait variation, this aspect is still poorly understood. It has been suggested that an increase in sperm competition pressure could reduce sperm size variation or produce a diversity of sperm to maximize male fertilization success. We aim at elucidating the variability of sperm morphometric traits and velocity in two Tupinambis lizards in the context of sperm competition risk. Sperm traits showed substantial variation at all levels examined: between species, among males within species, and within the ejaculate of individual males. Sperm velocity was found to be positively correlated with flagellum: midpiece ratio, with relatively longer flagella associated with faster sperm. Our results document high variability in sperm form and function in lizards. PMID:25505535

Blengini, Cecilia S; Sergio, Naretto; Gabriela, Cardozo; Giojalas, Laura C; Margarita, Chiaraviglio

2014-01-01

67

Variability in sperm form and function in the context of sperm competition risk in two Tupinambis lizards.  

PubMed

In polyandrous species, sperm morphometry and sperm velocity are under strong sexual selection. Although several hypotheses have been proposed to explain the role of sperm competition in sperm trait variation, this aspect is still poorly understood. It has been suggested that an increase in sperm competition pressure could reduce sperm size variation or produce a diversity of sperm to maximize male fertilization success. We aim at elucidating the variability of sperm morphometric traits and velocity in two Tupinambis lizards in the context of sperm competition risk. Sperm traits showed substantial variation at all levels examined: between species, among males within species, and within the ejaculate of individual males. Sperm velocity was found to be positively correlated with flagellum: midpiece ratio, with relatively longer flagella associated with faster sperm. Our results document high variability in sperm form and function in lizards. PMID:25505535

Blengini, Cecilia S; Sergio, Naretto; Gabriela, Cardozo; Giojalas, Laura C; Margarita, Chiaraviglio

2014-11-01

68

Relationship between sperm quality parameters and the fatty acid composition of the muscle, liver and testis of European eel.  

PubMed

This study looks at the correlations that fatty acids have with different tissues in the European eel (Anguilla anguilla L.) during hormonally-induced sexual maturation, with different sperm quality parameters. In order to evaluate the different dynamics of the use of fatty acids, a categorization of the results from each sperm quality parameter (volume, concentration, motility and velocity) was performed. Low and moderate correlations were observed between muscle tissue and some sperm quality parameters but no high correlations were found. Eicosapentaenoic acid (20:5n3, EPA) in the liver seems to have a role in determining the volume of sperm produced. This can be explained by the fact that EPA is a major requirement in the early phases of sperm production (probably as a component of the spermatozoal membrane). In addition, the levels of ?-linolenic acid (18:3-n3, ALA) and linoleic acid (18:2-n6, LA) in the liver decreased when sperm motility increased. In all the tissues, a negative correlation was observed between arachidonic acid (20:4n-6, ARA) and the different sperm velocity parameters. The fact that an increase in the consumption of ARA coincides with an increase in the speed of spermatozoa, highlights the important role that this fatty acid plays not only in sperm production, but also in sperm velocity. All this information could prove useful in the development of suitable broodstock diets to improve sperm quality and subsequently, the larval development of this species. PMID:25483240

Baeza, R; Mazzeo, I; Vílchez, M C; Gallego, V; Peñaranda, D S; Pérez, L; Asturiano, J F

2015-03-01

69

Preventive maintenance, the key to increased productivity  

SciTech Connect

In order to increase availability of equipment and therefore increase productivity, a new Preventive Maintenance Program was developed at Martin County Coal Corporation. Over the course of the first two years of the program, software and the method of compiling input information was developed. As soon as the program was in motion an increase in equipment availability was realized. As the program progressed, overburden removal and coal production began an upward trend while maintenance cost began to drop.

Bradbury, P.; Beatty, B.

1982-12-01

70

Diploid males, diploid sperm production, and triploid females in the ant Tapinoma erraticum  

NASA Astrophysics Data System (ADS)

Under complementary sex determination (CSD), females of Hymenoptera arise from diploid, fertilized eggs and males from haploid, unfertilized eggs. Incidentally, fertilized eggs that inherit two identical alleles at the CSD locus will develop into diploid males. Diploid males are usually unviable or sterile. In a few species, however, they produce diploid sperm and father a triploid female progeny. Diploid males have been reported in a number of social Hymenoptera, but the occurrence of triploid females has hardly ever been documented. Here, we report the presence of triploid females, diploid males, and diploid sperm (produced by diploid males and stored in queen spermathecae) in the ant Tapinoma erraticum. Moreover, we show variations in the frequency of triploids among female castes: Triploid females are more frequent among workers than virgin queens; they are absent among mated, reproductive queens. The frequency of triploid workers also varies between populations and between nests within populations.

Cournault, Laurent; Aron, Serge

2009-12-01

71

Cryopreservation of Greenshell™ Mussel (Perna canaliculus) Sperm.  

PubMed

Cryopreservation is a valuable technique for aquaculture as it enables a library or bank of genetically valuable animals to be maintained in a cost-effective manner. Here, we describe a method to cryopreserve the sperm of the Greenshell™ mussel (Perna canaliculus) and how to use the sperm post-thawing to maximize larval production from thawed sperm in selective breeding. PMID:25428014

Adams, Serean L; Smith, John F; Taylor, Jolene; McGowan, Lindsay T; Tervit, H Robin

2015-01-01

72

Increased incidence of disomic sperm nuclei in a 47,XYY male assessed by fluorescent in situ hybridization (FISH)  

Microsoft Academic Search

Using triple-colour fluorescent in situ hybridization in decondensed sperm heads, we assessed the sex-chromosome distribution\\u000a in spermatozoa from a 47,XYY male compared with controls. The incidence of spermatozoa with 24,XY (0.30%) and 24,YY (1.01%)\\u000a disomy was significantly higher than in our control series. Diploid meiocytes present in the ejaculate were mainly 47,XYY\\u000a (60.6–86.7%), and haploid meiocytes were mainly 24,XY (78.1%).These

Joan Blanco; Carmen Rubio; Carlos Simon; Josep Egozcue; Francesca Vidal

1997-01-01

73

Sperm epigenomics: challenges and opportunities  

PubMed Central

Sperm is a highly differentiated cell type whose function is to deliver a haploid genome to the oocyte. The sperm “epigenomes” were traditionally considered to be insignificant – the sperm is transcriptionally inactive, its genome is packaged in sperm-specific protamine toroids instead of nucleosomes, and its DNA methylation profile is erased immediately post-fertilization. Yet, in recent years there has been an increase in the number of reported cases of apparent epigenetic inheritance through the male germline, suggesting that the sperm epigenome may transmit information between generations. At the same time, technical advances have made the genome-wide profiling of different layers of the sperm epigenome feasible. As a result, a large number of datasets have been recently generated and analyzed with the aim to better understand what non-genetic material is contained within the sperm and whether it has any function post-fertilization. Here, we provide an overview of the current knowledge of the sperm epigenomes as well as the challenges in analysing them and the opportunities in understanding the potential non-genetic carriers of information in sperm. PMID:25278962

Casas, Eduard; Vavouri, Tanya

2014-01-01

74

Sperm storage in caecilian amphibians  

PubMed Central

Background Female sperm storage has evolved independently multiple times among vertebrates to control reproduction in response to the environment. In internally fertilising amphibians, female salamanders store sperm in cloacal spermathecae, whereas among anurans sperm storage in oviducts is known only in tailed frogs. Facilitated through extensive field sampling following historical observations we tested for sperm storing structures in the female urogenital tract of fossorial, tropical caecilian amphibians. Findings In the oviparous Ichthyophis cf. kohtaoensis, aggregated sperm were present in a distinct region of the posterior oviduct but not in the cloaca in six out of seven vitellogenic females prior to oviposition. Spermatozoa were found most abundantly between the mucosal folds. In relation to the reproductive status decreased amounts of sperm were present in gravid females compared to pre-ovulatory females. Sperm were absent in females past oviposition. Conclusions Our findings indicate short-term oviductal sperm storage in the oviparous Ichthyophis cf. kohtaoensis. We assume that in female caecilians exhibiting high levels of parental investment sperm storage has evolved in order to optimally coordinate reproductive events and to increase fitness. PMID:22672478

2012-01-01

75

Effect of male age on sperm traits and sperm competition success in the guppy (Poecilia reticulata).  

PubMed

Deleterious mutations can accumulate in the germline with age, decreasing the genetic quality of sperm and imposing a cost on female fitness. If these mutations also affect sperm competition ability or sperm production, then females will benefit from polyandry as it incites sperm competition and, consequently, minimizes the mutational load in the offspring. We tested this hypothesis in the guppy (Poecilia reticulata), a species characterized by polyandry and intense sperm competition, by investigating whether age affects post-copulatory male traits and sperm competition success. Females did not discriminate between old and young males in a mate choice experiment. While old males produced longer and slower sperm with larger reserves of strippable sperm, compared to young males, artificial insemination did not reveal any effect of age on sperm competition success. Altogether, these results do not support the hypothesis that polyandry evolved in response to costs associated with mating with old males in the guppy. PMID:19912453

Gasparini, C; Marino, I A M; Boschetto, C; Pilastro, A

2010-01-01

76

Identification and validation of mouse sperm proteins correlated with epididymal maturation  

PubMed Central

Sperm need to mature in the epididymis to become capable of fertilization. To understand the molecular mechanisms of mouse sperm maturation, we conducted a proteomic analysis using saturation dye labeling to identify proteins of caput and cauda epididymal sperm that exhibited differences in amounts or positions on two-dimensional gels. Of eight caput epididymal sperm-differential proteins, three were molecular chaperones and three were structural proteins. Of nine cauda epididymal sperm-differential proteins, six were enzymes of energy metabolism. To validate these proteins as markers of epididymal maturation, immunoblotting and immunofluorescence analyses were performed. During epididymal transit, heat shock protein 2 was eliminated with the cytoplasmic droplet and smooth muscle ?-actin exhibited reduced fluorescence from the anterior acrosome while the signal intensity of aldolase A increased, especially in the principal piece. Besides these changes, we observed protein spots, such as glutathione S-transferase mu 5 and the E2 component of pyruvate dehydrogenase complex, shifting to more basic isoelectric points, suggesting post-translational changes such dephosphorylation occur during epididymal maturation. We conclude that most caput epididymal sperm-differential proteins contribute to the functional modification of sperm structures and that many cauda epididymal sperm-differential proteins are involved in ATP production that promotes sperm functions such as motility. PMID:21805633

Ijiri, Takashi W.; Merdiushev, Tanya; Cao, Wenlei; Gerton, George L.

2012-01-01

77

Responses of testis, epididymis, and sperm of pubertal rats exposed to functionalized multiwalled carbon nanotubes.  

PubMed

The present study investigated the response of testes, epididymides and sperm in pubertal Wistar rats following exposure to 0, 0.25, 0.5, 0.75, and 1.0 mg kg(-1) functionalized multi-walled carbon nanotubes (f-MWCNTs) for 5 days. The results showed that administration of (f-MWCNTs) significantly increased the activities of superoxide dismutase, catalase, and glutathione peroxidase in a dose-dependent manner in both testes and sperm compared with control group. Moreover, the significant decrease in the activity of glutathione-S-transferase and glutathione level was accompanied with significant elevation in the levels of hydrogen peroxide and malondialdehyde in both testes and sperm of (f-MWCNTs)-treated rats. The spermiogram of (f-MWCNTs)-treated rats indicated significant decrease in epididymal sperm number, sperm progressive motility, testicular sperm number and daily sperm production with elevated sperm abnormalities when compared with the control. Exposure to (f-MWCNTs) decreased plasma testosterone level and produced marked morphological changes including decreased geminal epithelium, edema, congestion, reduced spermatogenic cells and focal areas of tubular degeneration in the testes. The lumen of the epididymides contained reduced sperm cells and there was mild to severe hyperplasia epithelial cells lining the duct of the epididymis. Collectively, pubertal exposure of male rats to (f-MWCNTs) elicited oxidative stress response resulting in marked testicular and epididymides dysfunction. © 2014 Wiley Periodicals, Inc. Environ Toxicol, 2014. PMID:25410135

Farombi, Ebenezer O; Adedara, Isaac A; Forcados, Gilead E; Anao, Osemudiamen O; Agbowo, Agatha; Patlolla, Anita K

2014-11-20

78

[Level of DNA fragmentation in human sperm cells in varicocele and prostatitis].  

PubMed

Varicocele and prostatitis are the most common andrological diseases, which may be accompanied by a decrease in the production of sperm cells, the deterioration of their quality and increased risk of infertility. This work was aimed to the evaluation of sperm DNA fragmentation index (DFI) and main indices of sperm fertility (concentration, motility and morphology), and the relationship between these parameters in the men of active reproductive age suffering from prostatitis or varicocele. Assessment of sperm DNA fragmentation was performed by SCSA (sperm chromatin structure assay) using flow cytometry; sperm parameters were evaluated according to WHO recommendations. It was shown that men with prostatitis (n = 9) and varicocele (n = 22) had significantly higher DFI compared with men in the control group (n = 22). Negative influence of these diseases on the concentration and the percentage of motile sperm cells in the ejaculate was revealed. These data suggest that the deterioration in the quality of semen in varicocele and prostatitis may be caused not only by pathospermia, but also, at least partially, by violation of the integrity of the sperm DNA. Evaluation of sperm DNA fragmentation can be recommended for use in laboratory diagnostics for prediction of fertility in infertile men. PMID:25211925

Osadchuk, L V; Erkovich, A A; Tataru, D A; Markova, E V; Svetlakov, A V

2014-01-01

79

Decoding mechanisms of loss of fertilization ability of cryopreserved mouse sperm  

NASA Astrophysics Data System (ADS)

Cryopreservation of mouse sperm is an important technology for management of biomedical research resources. Dramatic progress has been made recently in the development of protocols that combat mouse-strain specific reduction of IVF after cryopreservation. Equal emphasis, however, has not been placed on investigating the biological mechanisms underlying these improvements to IVF. This dissertation broadly investigates the basic question of how mouse-strain specific reduction of IVF occurs after cryopreservation, and how recently developed protocols prevent this process. My research investigated the effects of antioxidants, the cholesterol-acceptor CD, reduced calcium media, and TYH capacitation media on sperm function and oxidative stress after cryopreservation in a variety of mouse strains. I found that reduced IVF was associated with loss of capacitation-dependent sperm function in three strains, B6/J, B6/N, and 129X1, and CD improved sperm function and IVF in all three strains. These findings suggest that cryopreservation inhibits cholesterol efflux resulting in reduced IVF of many mouse strains. I also found that cryopreservation induces uniquely high production of mitochondrial H2O2 by B6/J sperm. H2O2 present in other cellular compartments of B6/J sperm was not elevated compared to other strains. High levels of mitochondrial H2O2 were associated with lipid peroxidation of the sperm head and inability to acrosome react. Antioxidants reduced mitochondrial H2O2 production, decreased sperm head lipid peroxidation, and improved acrosome reaction. The cryopreservation-induced increase in mitochondrial H2O2 production of B6/J and B6129XF1 sperm was associated with elevation of intracellular calcium after cryopreservation and dependent on mitochondrial metabolic substrates. Reducing intracellular calcium levels or removing mitochondrial metabolic substrates decreased mitochondrial H2O2 production and increased IVF rates of cryopreserved B6/J sperm. Many of the strains I tested exhibited increased H2O2 production after cryopreservation, but cryopreservation-induced H2O2 only interfered with IVF of B6/J sperm. This dissertation describes two means to improve IVF of cryopreserved sperm, mitigation of oxidative stress in B6/J sperm and improvement of capacitation-dependent sperm function for several mouse strains.

Gray, Jeffrey Earl

80

Effects of intratesticular zinc gluconate treatment on testicular dimensions, echodensity, histology, sperm production, and testosterone secretion in American black bears ( Ursus americanus)  

Microsoft Academic Search

Eight adult American black bears were used to evaluate the effects of chemical castration by intratesticular zinc gluconate treatment on testicular dimensions, echodensity, histology, sperm production, and testosterone secretion. Treatment did not affect testicular dimensions and did not result in decreased resting or GnRH-stimulated testosterone secretion. Multifocal hyperchoic areas in the testicular parenchyma were observed on ultrasound examination, and white

Leonardo F. C. Brito; Patricia L. Sertich; William Rives; Marc Knobbe; Fabio Del Piero; Gordon B. Stull

2011-01-01

81

50 bovine sperm death kinetics: temporal changes in production of reactive oxygen species and plasma membrane injury of dairy and beef frozen-thawed semen.  

PubMed

The extent of changes in sperm structure and function affect the success of fertilization ultimately during the pathway to ovum in the female reproductive tract. The success of AI with frozen-thawed semen varies in dairy and beef breeds of bovine because of differed alterations in sperm during transport in female tract after insemination. To our knowledge, no report is available comparing the changes in dairy and beef sperm leading to death in female tract. Therefore, this study was aimed to investigate the changes in motility, generation of reactive oxygen species (superoxide and hydrogen peroxide), and their relation to sperm death [asymmetry (apoptosis) and rupture of plasma membrane] of dairy and beef frozen-thawed semen during incubation at 37°C for 24h. This incubation was aimed to mimic the environment of female reproductive tract. Frozen dairy semen (n=4 bulls) was procured from a Canadian breeding station, whereas beef semen was collected from breeding beef bulls (n=3; 5 replicates), diluted with Tris-based extender (composition was same as used in dairy semen), cooled to +4°C over 90min, and cryopreserved by programmable freezer using standard rate as used in dairy semen. Two straws per replicate were thawed at 37°C from both types of semen, pooled separately, and incubated at 37°C for 24h in capped tubes. Each pooled semen sample was evaluated for motility with CASA, superoxide (O2(-), and hydrogen peroxide (H2O2) radical using HE/YoPRO and H2DCFDA/PI assay, respectively, and asymmetry of plasma membrane using YoPRO/PI assay through flow cytometric analysis at 0, 2, 4, 6, 12, and 24h of incubation. The MIXED procedure of SAS (SAS Institute Inc., Cary, NC, USA) was used to analyse the data as 2×6 factorial model for 2 types of semen (dairy and beef) and 6 time points using time as repeated measure. A threshold limit of 30% was considered for motility and live sperm to get optimum fertility. Sperm motility remained higher (P<0.05) than threshold limit till 6h in dairy (50.95±2.62%) and 2h in beef semen (30.28±6.95%). Dairy semen possessed more (P<0.05) nonapoptotic sperm without O2(-) (HE-/YoPRO-) till 6h of incubation than beef semen. The increase in apoptotic sperm containing superoxide radical (HE+/YoPRO+) over time was more (P<0.05) in beef semen till 6h of incubation. The rise in dead sperm containing H2O2 (H2DCFDA+/PI+) was recorded more in beef than in dairy semen until 6h of incubation. Live sperm without apoptosis (YoPRO-/PI-) were higher until 24h in dairy (49.36±4.56%) compared with beef semen (24.89±3.85%), whereas viable sperm with apoptosis (YoPRO+/PI-) were found similar in both types of semen over time. In conclusion, dairy frozen-thawed semen possessed more live sperm without reactive oxygen species (superoxide and hydrogen peroxide) until 6h of incubation than did beef semen. The decrease in superoxide radical was more in dairy than in beef semen. Dead and apoptotic sperm increased more in beef frozen-thawed semen over time during incubation. This inference suggests performing the insemination late near ovulation with beef frozen-thawed semen because of less viable life than dairy semen. PMID:25472099

Ahmad, M; Ahmad, N; Anzar, M

2014-12-01

82

[Role of fatty acids in sperm membrane].  

PubMed

One of causes of male infertility is reduced sperm motility. Reactive oxygen species (ROS) play significant role for physiological sperm function. Oxidative stress occurs when the production of potentially destructive ROS exceeds the natural antioxidant defences, resulting in cell damage. Sperm phospholipid polyunsaturated fatty acids are particularly susceptible to peroxidative damage by free radicals. Detrimental effects of lipid peroxidation should decrease sperm quality and be responsible of fertility problems. The review deals with sperm membrane composition, importance of fatty acids and prevention possibilities of oxidative cell damage. PMID:24874823

Stramová, X; Hampl, R; St?pán, J; Kan?ár, R

2014-04-01

83

Nematode sperm.  

PubMed

Parasitic nematode infections remain a major public health problem in many parts of the world. Because most of the current strategies aimed at controlling parasitic nematode infections have met with only limited success, it may be time to consider alternative approaches. An aspect of nematode biology that has drawn little attention as a target for control is the reproductive process. Although there are numerous facets of the overall reproductive biology of nematodes that hold potential as targets for intervention, Alan Scott here focuses on the male reproductive system, and outlines some of the known unique processes and characteristics of sperm formation and sperm function that could be exploited to block fertilization. PMID:15275275

Scott, A L

1996-11-01

84

Increasing the availability of national mapping products.  

USGS Publications Warehouse

A discussion of the means employed by the US Geological Survey to facilitate map usage, covering aspects of project Map Accessibility Program including special rolled and folded map packaging, new market testing, parks and campgrounds program, expanded map dealer program, new booklet-type State sales index and catalog and new USGS map reference code. The USGS is seen as the producer of a tremendous nation-wide inventory of topographic and related map products available in unprecedented types, formats and scales, and as endeavouring to increase access to its products. The new USGS map reference code is appended. -J.C.Stone

Roney, J.I.; Ogilvie, B.C.

1981-01-01

85

Increased productivity in flight with voice commanding  

NASA Technical Reports Server (NTRS)

Automatic Speech Recognition technology has matured to the point where it can provide a viable means of increasing productivity by naturalizing the man-machine interface. With ever increasing workloads being placed on astronauts, speech recognition may provide an alternative means of system controlling that would reduce the task burden. Voice commanding, allowing hands-free operation, can be especially effective during operations requiring simultaneous system control. A flight experiment is under development to demonstrate the operational effectiveness of voice control by commanding the Space Shuttle's Closed Circuit Television (CCIV) system. This experiment will help direct future applications of voice entry to space operations.

Jordan, W. T.

1985-01-01

86

Aspermy, Sperm Quality and Radiation in Chernobyl Birds  

PubMed Central

Background Following the Chernobyl nuclear power plant accident, large amounts of radionuclides were emitted and spread in the environment. Animals living in such contaminated areas are predicted to suffer fitness costs including reductions in the quality and quantity of gametes. Methodology/Principal Findings We studied whether aspermy and sperm quality were affected by radioactive contamination by examining ejaculates from wild caught birds breeding in areas varying in background radiation level by more than three orders of magnitude around Chernobyl, Ukraine. The frequency of males with aspermy increased logarithmically with radiation level. While 18.4% of males from contaminated areas had no sperm that was only the case for 3.0% of males from uncontaminated control areas. Furthermore, there were negative relationships between sperm quality as reflected by reduced sperm velocity and motility, respectively, and radiation. Conclusions/Significance Our results suggest that radioactive contamination around Chernobyl affects sperm production and quality. We are the first to report an interspecific difference in sperm quality in relation to radioactive contamination. PMID:24963711

Møller, Anders Pape; Bonisoli-Alquati, Andrea; Mousseau, Timothy A.; Rudolfsen, Geir

2014-01-01

87

The effects of male age on sperm DNA damage in healthy non-smokers  

SciTech Connect

The trend for men to have children at older ages raises concerns that advancing age may increase the production of genetically defective sperm, increasing the risks of transmitting germ-line mutations. We investigated the associations between male age and sperm DNA damage and the influence of several lifestyle factors in a healthy non-clinical group of 80 non-smokers (age: 22-80) with no known fertility problems using the sperm Comet analyses. The average percent of DNA that migrated out of the sperm nucleus under alkaline electrophoresis increased with age (0.18% per year, p=0.006); but there was no age association for damage measured under neutral conditions (p=0.7). Men who consumed >3 cups coffee per day had {approx}20% higher % tail DNA under neutral but not alkaline conditions compared to men who consumed no caffeine (p=0.005). Our findings indicate that (a) older men have increased sperm DNA damage associated with alkali-labile sites or single-strand DNA breaks, and (b) independent of age, men with substantial daily caffeine consumption have increased sperm DNA damage associated with double-strand DNA breaks. DNA damage in sperm can be converted to chromosomal aberrations and gene mutations after fertilization increasing the risks for developmental defects and genetic diseases among offspring.

Schmid, T; Eskenazi, B; Baumgartner, A; Marchetti, F; Young, S; Weldon, R; Anderson, D; Wyrobek, A

2006-03-08

88

Increase productivity with novel reactor design  

SciTech Connect

Hydrocarbon processing industry (HPI) operators have always desired flexible control over process temperature as the chemical reactions proceeded. By managing reaction temperature, petrochemical manufacturers can optimize other processing variables, thus increasing product yields and minimizing wastes and byproducts. Diverse requirements of the HPI have spawned many different reactor types. Each design has benefits but also limitations. Ongoing challenges in reactor development include large pressure drop, high catalyst inventory, labor-intensive change-out of catalysts, etc. Two case histories explore using adiabatic and nonadiabatic reactor technology for exothermic and endothermic reactions.

Arakawa, S.T.; Mulvaney, R.C.; Felch, D.E.; Petri, J.A.; Vandenbussche, K.; Dandekar, H.W. [UOP LLC, Des Plaines, IL (United States)

1998-03-01

89

Female presence influences sperm velocity in the guppy  

PubMed Central

As sperm production is costly, males are expected to strategically allocate resources to sperm production according to mating opportunities. While sperm number adjustments have been reported in several taxa, only a few studies investigated whether sperm quality shows adaptive plasticity as well. We tested this prediction in the guppy, Poecilia reticulata. A total of 46 males were initially stripped of all retrievable sperm before being randomly allocated to one of two treatments simulating different levels of mating opportunities (visual contact with females or female deprived). After 3 days, males were stripped and sperm velocity was assayed using Computer Assisted Sperm Analysis. Males in the presence of females produced significantly faster sperm than their counterparts. Implications for the evolution of this ejaculate plasticity in the light of results of sperm competition studies are discussed. PMID:19656863

Gasparini, Clelia; Peretti, Alfredo V.; Pilastro, Andrea

2009-01-01

90

Parameters of the reproductive tract, spermatogenesis, daily sperm production and major seminal plasma proteins of tropically adapted morada nova rams.  

PubMed

This study describes the reproductive parameters of Morada Nova rams, a breed of hair sheep from Brazil and with unique adaption to tropical environments. At 42 weeks of age, 15 rams were subjected to semen collection and, 1 week later, animals were slaughtered for collection of testes, epididymis and accessory sex glands. We conducted 2-D electrophoresis of seminal plasma proteins and major spots of stained gels were identified by LC-MS/MS. Total RNA was isolated from testis, epididymis and vesicular glands and subjected to qPCR. At slaughter, scrotal circumference and testicular weight were 27.5 ± 0.5 cm and 109.5 ± 6.0 g, respectively. Seminiferous tubule (ST) diameter was 188.3 ± 4.0 ?m and each testis contained 1.9 ± 0.1 Sertoli cells (×10(9) ). Each Sertoli cell supported 0.1 ± 0.01 A spermatogonia, 3.0 ± 0.2 pachytene spermatocytes and 7.7 ± 0.5 round spermatids/tubule cross section. Daily sperm production reached 5.6 × 10(6)  cells/g of testis parenchyma. Testis size appeared as indicative of ST diameter and associated with epididymal measurements, as well as with the population of round spermatids and Sertoli cells/testis. Rams with heavier testes had greater daily sperm production and more Sertoli cells/testis. We detected 90.9 ± 9.6 spots per 2-D gel of seminal plasma. Major seminal proteins were identified as ram seminal vesicle proteins at 14 and 22 kDa, representing 16.2% and 12.8% of the total intensity of valid spots in the gels, respectively. Expression of both genes was greater in the vesicular glands as compared to testis and epididymis. Pixel intensity for those proteins in the 2-D gels was significantly correlated with seminal vesicle weight. This is the first description of the basic reproductive aspects of Morada Nova rams, including protein profiles of their seminal plasma. These findings will allow a better understanding of their reproductive physiology. PMID:24716618

Sousa, F M L; Lobo, C H; Menezes, E S B; Rego, J P A; Oliveira, R V; Lima-Souza, A C; Fioramonte, M; Gozzo, F C; Pompeu, R C F F; Cândido, M J D; Oliveira, J T; Moura, A A

2014-06-01

91

Body condition influences sperm energetics in lake whitefish ( Coregonus clupeaformis )  

Microsoft Academic Search

Theoretical models predict that individual males will increase their investment in ejaculates when there is a risk of sperm competition. Because the production of ejaculates is assumed to be energetically costly, only those males in good physical condition should be capable of producing ejaculates of high quality. We studied ejaculate investment (relative testis size, controlling for body size) as well

Gary Burness; Albrecht I. Schulte-Hostedde; Robert Montgomerie

2008-01-01

92

Fire increases dust production from chaparral soils  

NASA Astrophysics Data System (ADS)

By altering the physical and chemical properties of a landscape, fire may increase its vulnerability to erosive processes. Whereas sediment transport by surface runoff after fires has been often investigated, less is known about the role of wind erosion in burned terrain. To examine how fire might increase a soil's vulnerability to aeolian transport, intact soil samples were collected from a chaparral landscape in southern California and heated with a propane torch with temperatures ranging from 250 to 1025 °C and for durations of 5-60 min to simulate a variety of burn severities. The samples were then subjected to simulated wind and the amounts of eroded sediment were measured. Results indicate a linear increase in the production of wind-erodible sediment with applied heat up to ~ 10 MJ/m2. The increase was not due to a reduction in the threshold shear velocity of the soil surface but, instead, to the role of heat in detaching erodible material. In these soils, organic material may be an important binding agent destroyed at high temperatures. The relationship between fire and erodibility is complex, however, because heating may also help to aggregate soil particles. Experiments performed here also suggest a synergistic effect between fire and rain whereby heated soils are more vulnerable to the erosive power of raindrop impacts. Additionally, the soil heating experiments were used to measure and compare the thermal conductivities of intact and disturbed soils. Finally, it is concluded that soil heating may increase the emission of dust through the detachment of erodible particles, a result that may help in the anticipation of respiratory problems for those living downwind of burned areas.

Gabet, Emmanuel J.

2014-07-01

93

Tactic-specific differences in seminal fluid influence sperm performance  

PubMed Central

Seminal fluid often makes up a large part of an ejaculate, yet most empirical and theoretical studies on sperm competition have focused on how sperm characteristics (number and quality) affect fertilization success. However, seminal fluid influences own sperm performance and may potentially influence the outcome of sperm competition, by also affecting that of rivals. As a consequence males may be expected to allocate their investment in both sperm and seminal fluid in relation to the potential level of competition. Grass goby (Zosterisessor ophiocephalus) is an external fertilizer with guard-sneaker mating tactics, where sperm competition risk varies according to the tactic adopted. Here, we experimentally manipulated grass goby ejaculates by separately combining sperm and seminal fluid from territorial and sneaker males. While sperm of sneaker and territorial males did not differ in their performance when they interacted with their own seminal fluid only, sperm of sneakers increased their velocity and fertilization rate in the presence of territorial males' seminal fluid. By contrast, sneaker males' seminal fluid had a detrimental effect on the performance of territorial males' sperm. Sperm velocity was unaffected by the seminal fluid of males employing the same tactic, suggesting that seminal fluid's effect on rival-tactic sperm is not based on a self/non-self recognition mechanism. Our findings show that cross interactions of sperm and seminal fluid may influence the fertilization success of competing ejaculates with males investing in both sperm and seminal fluid in response to sperm competition risk. PMID:23363633

Locatello, Lisa; Poli, Federica; Rasotto, Maria B.

2013-01-01

94

Maturity stage and plasma testosterone levels are related to sperm production in blue catfish Ictalurus furcatus  

Technology Transfer Automated Retrieval System (TEKTRAN)

Recently, the channel catfish, Ictalurus puntatus' X blue catfish, I.furcatus ' F1 hybrid has demonstrated good potential for commercial production compared to the commonly raised channel catfish. Efforts by researchers and commercial producers in the last 40 years have improved hybrid fry product...

95

Effect of manganese supplementation on the membrane integrity and the mitochondrial potential of the sperm of grazing Nelore bulls.  

PubMed

The effect of dietary manganese (Mn(2+)) supplementation on the reproductive performance of Nelore bulls was evaluated by assessment of sperm membrane integrity. Sixty Nelore bulls (Bos taurus indicus) aged 18-20 mo were randomly divided into four groups (n=15) receiving dietary Mn(2+) supplementation at 540, 1300, 3800 and 6300mg/kg (treatments TC, T1300, T3800 and T6300, respectively). The diets were changed for the groups every 70d. Semen samples were obtained 15 and 56d after the diet change, which corresponded to the period of adjustment to the new diet and the time required for a complete spermatogenesis cycle, respectively. Sperm integrity was assessed by detection of: intact (IMe) or damaged (DMe) membranes, intact (IA) or damaged (DA) acrosomes, and high (HM) or low (LM) mitochondrial membrane potentials. Only bulls from the TC treatment showed a significant increase in the production of intact sperm [IMe/IA/LM] and decrease in the production of sperm with damaged acrosome [IMe/DA/LM] or completely damaged sperm [DMe/DA/LM] (P<0.05). The Mn(2+) concentrations in the semen were positively correlated with the incidence of sperm with IMe, DA, and LM and negatively correlated with number of sperm with DMe, IA, and LM. Therefore, dietary Mn(2+) supplementation for Nelore bulls must be limited to 540mg of Mn(2+)/kg given that higher doses are detrimental to the integrity of the plasma and acrosomal sperm membranes. PMID:25216627

Reis, L S L S; Ramos, A A; Camargos, A S; Oba, E

2014-11-10

96

Bioenergy Research at BNL: Increasing Productivity Using  

E-print Network

biomass for energy production as well as oil for biodiesel #12;Biosolid Comparision of Seed Mass per Plant.SeedMassinGrams Seed mass per plant #12;Biomass per plant #12;Poplar trees for biomass production and cleaning ­ improved plant growth, health and survival, leading to economically sustainable feedstock production

Homes, Christopher C.

97

Sperm competitiveness in frogs: slow and steady wins the race  

PubMed Central

When sperm compete to fertilize available ova, selection is expected to favour ejaculate traits that contribute to a male's fertilization success. While there is much evidence to show that selection favours increased numbers of sperm, only a handful of empirical studies have examined how variation in sperm form and function contributes to competitive fertilization success. Here, we examine selection acting on sperm form and function in the externally fertilizing myobatrachid frog, Crinia georgiana. Using in vitro fertilization techniques and controlling for variation in the number of sperm contributed by males in competitive situations, we show that males with a greater proportion of motile sperm, and motile sperm with slower swimming velocities, have an advantage when competing for fertilizations. Sperm morphology and the degree of genetic similarity between putative sires and the female had no influence on competitive fertilization success. These unusual patterns of selection might explain why frog sperm typically exhibit relatively slow swimming speeds and sustained longevity. PMID:19710059

Dziminski, Martin A.; Roberts, J. Dale; Beveridge, Maxine; Simmons, Leigh W.

2009-01-01

98

Cryopreservation of Fish Sperm  

NASA Astrophysics Data System (ADS)

Present status of research activities in cryopreservation of fish gamete in aquaculture field was introduced. More than 59 fish species have been reported in the research histories and nearly half of them were studied during recent 10 years. This means that the research activities are increasing, though commercial profit have not obtained yet. Fish species of which sperm can successfully cryopreserved is still limited comparing to numerous species in telost. One of the major obstacle for improvement of the technique is existence of wide specie specific variance in the freezing tolerance of fish sperm. The varianc can possibly be explaind thorugh the informations obtained by the studies in comparative spermatology, which is recently activated field in fish biology.

Kurokura, Hisashi

99

Sperm motility of externally fertilizing fish and amphibians.  

PubMed

We review the phylogeny, sperm competition, morphology, physiology, and fertilization environments of the sperm of externally fertilizing fish and amphibians. Increased sperm competition in both fish and anurans generally increases sperm numbers, sperm length, and energy reserves. The difference between the internal osmolarity and iconicity of sperm cells and those of the aquatic medium control the activation, longevity, and velocity of sperm motility. Hypo-osmolarity of the aquatic medium activates the motility of freshwater fish and amphibian sperm and hyperosmolarity activates the motility of marine fish sperm. The average longevity of the motility of marine fish sperm (~550 seconds) was significantly (P < 0.05) greater than that of freshwater fish sperm (~150 seconds), with the longevities of both marine and freshwater fish being significantly (P < 0.05) lower than that of anuran sperm (~4100 seconds). The average velocity of anuran sperm (25 ?m/s) was significantly (P < 0.05) lower than that of marine fish (140 ?m/s) or freshwater fish (135 ?m/s) sperm. The longevity of the sperm of giant salamanders (Cryptobranchoidea) of approximately 600 seconds was greater than that of freshwater fish sperm but much lower than anuran sperm. Our research and information from the literature showed that higher osmolarities promote greater longevity in anuran sperm, and some freshwater fish sperm, and that anuran and cryptobranchid sperm maintained membrane integrity long after the cessation of motility, demonstrating a preferential sharing of energy reserves toward the maintenance of membrane integrity. The maintenance of the membrane integrity of anuran sperm in fresh water for up to 6 hours showed an extremely high osmotic tolerance relative to fish sperm. The very high longevity and osmotic tolerance of anuran sperm and high longevity of cryptobranchid sperm, relative to those of freshwater fish, may reflect the complex fertilization history of amphibian sperm in general and anurans reversion from internal to external fertilization. Our findings provide a greater understanding of the reproductive biology of externally fertilizing fish and amphibians, and a biological foundation for the further development of reproduction technologies for their sustainable management. PMID:25442393

Browne, R K; Kaurova, S A; Uteshev, V K; Shishova, N V; McGinnity, D; Figiel, C R; Mansour, N; Agney, D; Wu, M; Gakhova, E N; Dzyuba, B; Cosson, J

2015-01-01

100

Sperm Trajectories Form Chiral Ribbons  

PubMed Central

We report the discovery of an entirely new three-dimensional (3D) swimming pattern observed in human and horse sperms. This motion is in the form of ‘chiral ribbons’, where the planar swing of the sperm head occurs on an osculating plane creating in some cases a helical ribbon and in some others a twisted ribbon. The latter, i.e., the twisted ribbon trajectory, also defines a minimal surface, exhibiting zero mean curvature for all the points on its surface. These chiral ribbon swimming patterns cannot be represented or understood by already known patterns of sperms or other micro-swimmers. The discovery of these unique patterns is enabled by holographic on-chip imaging of >33,700?sperm trajectories at >90–140?frames/sec, which revealed that only ~1.7% of human sperms exhibit chiral ribbons, whereas it increases to ~27.3% for horse sperms. These results might shed more light onto the statistics and biophysics of various micro-swimmers' 3D motion. PMID:23588811

Su, Ting-Wei; Choi, Inkyum; Feng, Jiawen; Huang, Kalvin; McLeod, Euan; Ozcan, Aydogan

2013-01-01

101

Wonders of the Seas: Sperm Whales  

NSDL National Science Digital Library

Overview of sperm whale biology, adaptations, and behaviors. Basic introduction to anatomy, diet, echolocation, diving, whale oil and other products derived from sperm whales, whaling industry and impacts, and conservation measures. Accessible text, illustrated with excellent photographs. A NSTA SciLinks selected site.

102

Mass-Specific Metabolic Rate and Sperm Competition Determine Sperm Size in Marsupial Mammals  

PubMed Central

Two complementary hypotheses have been proposed to explain variation in sperm size. The first proposes that post-copulatory sexual selection favors an increase in sperm size because it enhances sperm swimming speed, which is an important determinant of fertilization success in competitive contexts. The second hypothesis proposes that mass-specific metabolic rate acts as a constraint, because large animals with low mass-specific metabolic rates will not be able to process resources at the rates needed to produce large sperm. This constraint is expected to be particularly pronounced among mammals, given that this group contains some of the largest species on Earth. We tested these hypotheses among marsupials, a group in which mass-specific metabolic rates are roughly 30% lower than those of eutherian mammals of similar size, leading to the expectation that metabolic rate should be a major constraint. Our findings support both hypotheses because levels of sperm competition are associated with increases in sperm size, but low mass-specific metabolic rate constrains sperm size among large species. We also found that the relationship between sperm size and mass-specific metabolic rate is steeper among marsupials and shallower among eutherian mammals. This finding has two implications: marsupials respond to changes in mass-specific metabolic rate by modifying sperm length to a greater extent, suggesting that they are more constrained by metabolic rate. In addition, for any given mass-specific metabolic rate, marsupials produce longer sperm. We suggest that this is the consequence of marsupials diverting resources away from sperm numbers and into sperm size, due to their efficient sperm transport along the female tract and the existence of mechanisms to protect sperm. PMID:21731682

Tourmente, Maximiliano; Gomendio, Montserrat; Roldan, Eduardo R. S.

2011-01-01

103

HDAC6 deacetylates alpha tubulin in sperm and modulates sperm motility in Holtzman rat.  

PubMed

Histone deacetylase 6 (HDAC6) is an alpha (?)-tubulin deacetylase and its over-expression has been demonstrated to promote chemotactic cell movement. Motility in sperm is driven by the flagella, the cytoskeletal structure comprising the microtubules, which are heterodimers of ?- and ?-tubulins. We have hypothesized that HDAC6, by virtue of being an ?-tubulin deacetylase, might modulate sperm motility. However, the presence of HDAC6 on sperm has hitherto not been reported. In this study, we have demonstrated, for the first time, the presence of HDAC6 transcript and protein in the testicular and caudal sperm of rat. We have observed a significantly overlapping expression of HDAC6 with acetyl ?-tubulin (Ac ?-tubulin) in the mid-piece and principal piece of sperm flagella, and the co-precipitation of ?-tubulin and Ac ?-tubulin together with HDAC6 and vice versa in sperm lysates. This indicates that HDAC6 interacts with ?-tubulin. The HDAC6 activity of sperm, sperm motility and status of Ac ?-tubulin investigated in the presence of HDAC inhibitors Trichostatin A, Tubastatin A and sodium butyrate demonstrate that HDAC6 in sperm is catalytically active and that inhibitors of HDAC6 increase acetylation and restrict sperm motility. Thus, we show that (1) active HDAC6 enzyme is present in sperm, (2) HDAC6 in sperm is able to deacetylate ?-tubulin, (3) inhibition of HDAC6 results in increased Ac ?-tubulin expression and (4) HDAC6 inhibition affects sperm motility. This evidence suggests that HDAC6 is involved in modulating sperm movement. PMID:25411052

Parab, Sweta; Shetty, Omshree; Gaonkar, Reshma; Balasinor, Nafisa; Khole, Vrinda; Parte, Priyanka

2014-11-20

104

In vitro production of llama (Lama glama) embryos by intracytoplasmic sperm injection: effect of chemical activation treatments and culture conditions.  

PubMed

Assisted reproductive technologies in the llama (Lama glama) are needed to provide alternative methods for the propagation, selection and genetic improvement; however, recovery of adequate quantity and quality of spermatozoa for conventional IVF is problematic. Therefore, an effort was made to adapt the intracytoplasmic sperm injection (ICSI) procedure for the in vitro production of llama embryos. The specific objectives of this study were: (1) to determine in vitro maturation rates of oocytes recovered by transvaginal ultrasound-guided oocyte aspiration (TUGA) or flank laparotomy; (2) to evaluate the effects of activation treatments following ICSI; (3) to evaluate the development of llama ICSI embryos in CR1aa medium or in an oviduct cell co-culture system. Llamas were superstimulated by double dominant follicle reduction followed by oFSH administered in daily descending doses over a 3-day interval. Oocytes were harvested by flank laparotomy or TUGA and matured in vitro for 30 h. Mature oocytes were subjected to ICSI followed by no chemical activation (Treatment A), ionomycin only (Treatment B) or ionomycin/DMAP activation (Treatment C). More oocytes were recovered by flank laparotomy procedure compared with TUGA (94% versus 61%, P<0.05) and a greater number of oocytes harvested by flank laparotomy reached the metaphase-II stage (77% versus 44%, P<0.05). After ICSI, the proportion of cleaved and 4-8-cell stages embryos was significantly greater when injected oocytes were activated with ionomycin/DMAP combination (63% and 38%, respectively, P<0.05). The co-culture of ICSI embryos with llama oviduct epithelial cells resulted in progression to morula (25%) and blastocyst (12%) stages; whereas, all embryos cultured in CR1aa medium arrested at the 8-16-cell developmental stage. PMID:16846701

Sansinena, M J; Taylor, S A; Taylor, P J; Schmidt, E E; Denniston, R S; Godke, R A

2007-06-01

105

Increasing productivity accelerates host–parasite coevolution  

Microsoft Academic Search

Host-parasite coevolution is believed to influence a range of evolutionary and ecological processes, including population dynamics, evolution of diversity, sexual reproduction and parasite virulence. The impact of coevolution on these processes will depend on its rate, which is likely to be affected by the energy flowing through an ecosystem, or productivity. We addressed how productivity affected rates of coevolution during

L. d. C. LOPEZ-PASCUA; A. BUCKLING

2008-01-01

106

LONG-TERM EFFECTS OF TRIETHYLENEMELAMINE EXPOSURE ON MOUSE TESTIS CELLS AND SPERM CHROMATIN STRUCTURE ASSAYED BY FLOW CYTOMETRY  

EPA Science Inventory

The toxic and potentially mutagenic actions of triethylenemelamine (TEM) on mouse body and testis weights, testicular cell kinetics, sperm production, sperm head morphology, and sperm chromatin structure were assessed in two experiments. he first experiment examined effects of fo...

107

Seasonal occurrence of sperm whales (Physeter macrocephalus) around Kelvin Seamount in the Sargasso Sea in relation to oceanographic processes  

NASA Astrophysics Data System (ADS)

Sperm whales (Physeter macrocephalus) are widely distributed in all oceans, but they are clumped geographically, generally in areas associated with high primary and secondary productivity. The warm, clear waters of the Sargasso Sea are traditionally thought to be low in productivity, however recent surveys have found large numbers of sperm whales there. The New England Seamount Chain bisects the north-western portion of the Sargasso Sea, and might influence the mesoscale eddies associated with the Gulf Stream; creating areas of higher productivity within the Sargasso Sea. We investigated the seasonal occurrence of sperm whales over Kelvin Seamount (part of the New England Seamount Chain) and how it is influenced by oceanographic variables. An autonomous recording device was deployed over Kelvin Seamount from May to June 2006 and November 2006 to June 2007. A total of 6505 hourly two-minute recordings were examined for the presence of sperm whale echolocation clicks. Sperm whales were more prevalent around Kelvin in the spring (April to June: mean=51% of recordings contained clicks) compared to the winter (November to March: mean=16% of recordings contained clicks). Sperm whale prevalence at Kelvin was related to chlorophyll-a concentration four weeks previous, eddy kinetic energy and month. The mesoscale activity associated with the Gulf Stream and the Gulf Stream's interaction with the New England Seamount Chain likely play an important role in sperm whale occurrence in this area, by increasing productivity and perhaps concentration of cephalopod species.

Wong, Sarah N. P.; Whitehead, Hal

2014-09-01

108

Sexual selection, germline mutation rate and sperm competition  

PubMed Central

Background An important component of sexual selection arises because females obtain viability benefits for their offspring from their mate choice. Females choosing extra-pair fertilization generally favor males with exaggerated secondary sexual characters, and extra-pair paternity increases the variance in male reproductive success. Furthermore, females are assumed to benefit from 'good genes' from extra-pair sires. How additive genetic variance in such viability genes is maintained despite strong directional selection remains an evolutionary enigma. We propose that sexual selection is associated with elevated mutation rates, changing the balance between mutation and selection, thereby increasing variance in fitness and hence the benefits to be obtained from good genes sexual selection. Two hypotheses may account for such elevated mutation: (1) Increased sperm production associated with sperm competition may increase mutation rate. (2) Mutator alleles increase mutation rates that are revealed by the expression of condition-dependent secondary sexual characters used by choosy females during their mate choice. M Petrie has independently developed the idea that mutator alleles may account for the maintenance of genetic variation in viability despite strong directional selection. Results A comparative study of birds revealed a positive correlation between mutation rate at minisatellite loci and extra-pair paternity, but not between mutation rate and relative testes mass which is a measure of relative sperm production. Minisatellite mutation rates were not related to longevity, suggesting a meiotic rather than a mitotic origin of mutations. Conclusion We found evidence of increased mutation rate in species with more intense sexual selection. Increased mutation was not associated with increased sperm production, and we suggest that species with intense sexual selection may maintain elevated mutation rates because sexual selection continuously benefits viability alleles expressed in condition-dependent characters. Sexual selection may increase mutational input, which in turn feeds back on sexual selection because of increased variance in viability traits. PMID:12702218

Møller, AP; Cuervo, JJ

2003-01-01

109

Experimental evolution of sperm competitiveness in a mammal  

PubMed Central

Background When females mate with multiple partners, sperm from rival males compete to fertilise the ova. Studies of experimental evolution have proven the selective action of sperm competition on male reproductive traits. However, while reproductive traits may evolve in response to sperm competition, this does not necessarily provide evidence that sperm competitive ability responds to selection. Indeed, a study of Drosophila failed to observe divergence in sperm competitive ability of males in lines selected for enhanced sperm offence and defence. Results Adopting the naturally polygamous house mouse (Mus domesticus) as our vertebrate model, we performed an experimental evolution study and observed genetic divergence in sperm quality; males from the polygamous selection lines produced ejaculates with increased sperm numbers and greater sperm motility compared to males from the monogamous lines. Here, after 12 generations of experimental evolution, we conducted competitive matings between males from lineages evolving under sperm competition and males from lineages subject to relaxed selection. We reduced variation in paternity arising from embryo mortality by genotyping embryos in utero at 14 days gestation. Our microsatellite data revealed a significant paternity bias toward males that evolved under the selective regime of sperm competition. Conclusion We provide evidence that the sperm competitiveness phenotype can respond to selection, and show that improved sperm quality translates to greater competitive fertilisation success in house mice. PMID:21251249

2011-01-01

110

Imbalanced lipid homeostasis in the conditional Dicer1 knockout mouse epididymis causes instability of the sperm membrane.  

PubMed

During epididymal sperm maturation, the lipid content of the sperm membrane is modified, which facilitates sperm motility and fertility. However, little is known about the mechanisms regulating the maturation process. By generating a conditional knockout (cKO) of Dicer1 in the proximal part of the mouse epididymis, we studied the role of RNA interference in epididymal functions. The Dicer1 cKO epididymis displayed an altered lipid homeostasis associated with a 0.6-fold reduction in the expression of the gene elongation of very long chain fatty acids-like 2, an enzyme needed for production of long-chain polyunsaturated fatty acids (PUFAs). Furthermore, the expression of several factors involved in cholesterol synthesis was up-regulated. Accordingly, the Dicer1 cKO sperm membrane showed a 0.7-fold decrease in long-chain PUFAs, whereas the amount of cholesterol in acrosome-reacted sperm displayed a 1.7-fold increase. The increased cholesterol:PUFA ratio of the sperm membrane caused breakage of the neck and acrosome region and immotility of sperm. Dicer1 cKO mice sperm also displayed reduced ability to bind to and fertilize the oocyte in vitro. This study thus shows that Dicer1 is critical for lipid synthesis in the epididymis, which directly affects sperm membrane integrity and male fertility.- Björkgren, I., Gylling, H., Turunen, H., Huhtaniemi, I., Strauss, L., Poutanen, M., Sipilä, P. Imbalanced lipid homeostasis in the conditional Dicer1 knockout mouse epididymis causes instability of the sperm membrane. PMID:25366345

Björkgren, Ida; Gylling, Helena; Turunen, Heikki; Huhtaniemi, Ilpo; Strauss, Leena; Poutanen, Matti; Sipilä, Petra

2015-02-01

111

Recovery and cryopreservation of epididymal sperm of plains bison (Bison bison bison) as a model for salvaging the genetics of wood bison (Bison bison athabascae).  

PubMed

The objective of this study was to optimize recovery and cryopreservation of epididymal sperm from plains bison, as a model for wood bison. In Phase 1, cauda epididymides were recovered from bison (n = 14) immediately after slaughter, minced and incubated in Sp-TALPH buffer for 3 h at 36 degrees C. The resulting sperm suspensions were cryopreserved in Triladyl, using a protocol for bovine semen. In Phase 2, epididymal sperm were cryopreserved in either Triladyl or Andromed. The mean (+/-SD) estimated number of sperm recovered was 468 +/- 207 x 10(6). There was an increase (p < 0.05) in the proportion of sperm with normal morphology between initial recovery and after extension (52.4 +/- 4.6 vs 69.7 +/- 2.4%), with a concurrent decrease (p < 0.05) in the proportion of sperm with distal droplets. Median values for progressively motile sperm in post-thaw samples (60%) were lower (p < 0.05) than that after extension or after chilling (70% for both). The mean percentages of viable sperm and of sperm with an intact acrosome were lower (p < 0.05) for frozen-thawed samples (38.7 +/- 2.8 and 85.2 +/- 1.1) compared with extended (66.2 +/- 2.2 and 92.4 +/- 0.9) or chilled (63.7 +/- 2.5 and 90.0 +/- 1.0) samples. Rates of cleavage, morulae and blastocyst production were not significantly different for chilled (70.9, 38.7 and 8.0%) vs post-thaw sperm (73.0, 46.0 and 6.3%). There was no significant difference between extenders for most sperm characteristics. In conclusion, we developed a functional protocol for the recovery and cryopreservation of epididymal sperm from plains bison, which may have implications for the genetic preservation of wood bison. PMID:18811627

Aurini, L C; Whiteside, D P; Elkin, B T; Thundathil, J C

2009-10-01

112

Detection of structural and numerical chomosomal abnormalities by ACM-FISH analysis in sperm of oligozoospermic infertility patients  

SciTech Connect

Modern reproductive technologies are enabling the treatment of infertile men with severe disturbances of spermatogenesis. The possibility of elevated frequencies of genetically and chromosomally defective sperm has become an issue of concern with the increased usage of intracytoplasmic sperm injection (ICSI), which can enable men with severely impaired sperm production to father children. Several papers have been published about aneuploidy in oligozoospermic patients, but relatively little is known about chromosome structural aberrations in the sperm of these patients. We examined sperm from infertile, oligozoospermic individuals for structural and numerical chromosomal abnormalities using a multicolor ACM FISH assay that utilizes DNA probes specific for three regions of chromosome 1 to detect human sperm that carry numerical chromosomal abnormalities plus two categories of structural aberrations: duplications and deletions of 1pter and 1cen, and chromosomal breaks within the 1cen-1q12 region. There was a significant increase in the average frequencies of sperm with duplications and deletions in the infertility patients compared with the healthy concurrent controls. There was also a significantly elevated level of breaks within the 1cen-1q12 region. There was no evidence for an increase in chromosome-1 disomy, or in diploidy. Our data reveal that oligozoospermia is associated with chromosomal structural abnormalities suggesting that, oligozoospermic men carry a higher burden of transmissible, chromosome damage. The findings raise the possibility of elevated levels of transmissible chromosomal defects following ICSI treatment.

Schmid, T E; Brinkworth, M H; Hill, F; Sloter, E; Kamischke, A; Marchetti, F; Nieschlag, E; Wyrobek, A J

2003-11-10

113

Sensors Increase Productivity in Harsh Environments  

NASA Technical Reports Server (NTRS)

California's San Juan Capistrano-based Endevco Corporation licensed three patents covering high-temperature, harsh-environment silicon carbide (Si-C) pressure sensors from Glenn Research Center. The company is exploring their use in government markets, as well as in commercial markets, including commercial jet testing, deep well drilling applications where pressure and temperature increase with drilling depth, and in automobile combustion chambers.

2008-01-01

114

Regulation of axonemal motility in demembranated equine sperm.  

PubMed

Equine in vitro fertilization is not yet successful because equine sperm do not effectively capacitate in vitro. Results of previous studies suggest that this may be due to failure of induction of hyperactivated motility in equine sperm under standard capacitating conditions. To evaluate factors directly affecting axonemal motility in equine sperm, we developed a demembranated sperm model and analyzed motility parameters in this model under different conditions using computer-assisted sperm analysis. Treatment of ejaculated equine sperm with 0.02% Triton X-100 for 30 sec maximized both permeabilization and total motility after reactivation. The presence of ATP was required for motility of demembranated sperm after reactivation, but cAMP was not. The calculated intracellular pH of intact equine sperm was 7.14 ± 0.07. Demembranated sperm showed maximal total motility at pH 7. Neither increasing pH nor increasing calcium levels, nor any interaction of the two, induced hyperactivated motility in demembranated equine sperm. Motility of demembranated sperm was maintained at free calcium concentrations as low as 27 pM, and calcium arrested sperm motility at much lower concentrations than those reported in other species. Calcium arrest of sperm motility was not accompanied by flagellar curvature, suggesting a failure of calcium to induce the tonic bend seen in other species and thought to support hyperactivated motility. This indicated an absence, or difference in calcium sensitivity, of the related asymmetric doublet-sliding proteins. These studies show a difference in response to calcium of the equine sperm axoneme to that reported in other species that may be related to the failure of equine sperm to penetrate oocytes in vitro under standard capacitating conditions. Further work is needed to determine the factors that stimulate hyperactivated motility at the axonemal level in equine sperm. PMID:25339104

Loux, Shavahn C; Macías-Garcia, Beatríz; González-Fernández, Lauro; Canesin, Heloisa DeSiqueira; Varner, Dickson D; Hinrichs, Katrin

2014-12-01

115

A C. elegans sperm TRP protein required for sperm-egg interactions during fertilization.  

PubMed

Fertilization, a critical step in animal reproduction, is triggered by a series of specialized sperm-egg interactions. However, the molecular mechanisms underlying fertilization are not well understood. Here, we identify a sperm-enriched C. elegans TRPC homolog, TRP-3. Mutations in trp-3 lead to sterility in both hermaphrodites and males due to a defect in their sperm. trp-3 mutant sperm are motile, but fail to fertilize oocytes after gamete contact. TRP-3 is initially localized in intracellular vesicles, and then translocates to the plasma membrane during sperm activation. This translocation coincides with a marked increase in store-operated calcium entry, providing an in vivo mechanism for the regulation of TRP-3 activity. As C. elegans oocytes lack egg coats, our data suggest that some TRPC family channels might function to mediate calcium influx during sperm-egg plasma membrane interactions leading to fertilization. PMID:12914694

Xu, X-Z Shawn; Sternberg, Paul W

2003-08-01

116

Early Eocene climate warming increased petroleum production  

NASA Astrophysics Data System (ADS)

From the late Paleocene, about 58 million years ago, to the early Eocene, about 51 million years ago, Earth's surface temperatures warmed by about 5°-10°C. Also in the early Eocene, there was an increase of carbon-13-depleted carbon in the oceans that cannot be accounted for by changes in carbon cycling at the surface. To better understand the source of that carbon, Kroeger and Funnell modeled the thermal evolution of four sedimentary basins in the southwestern Pacific Ocean. The authors show that the rising surface temperatures of the early Eocene eventually led to warming of the sedimentary beds deep beneath the surface. Petroleum can be produced at only a certain range of temperatures; rising temperatures at greater depths would bring more potential source rocks into temperature conditions under which oil and gas can be produced and released.

Balcerak, Ernie

2012-04-01

117

Sperm competition in bats  

Microsoft Academic Search

SUMMARY Sperm competition is a widespread phenomenon influencing the evolution of male anatomy, physiology and behaviour. Bats are an ideal group for studying sperm competition. Females store fertile sperm for up to 200 days and the size of social groups varies from single animals to groups of hundreds of thousands. This study examines the relationship between social group size and

D. J. Hosken

1997-01-01

118

Fertilization by proxy: rival sperm removal and translocation in a beetle  

Microsoft Academic Search

Competition between di¡erent males' sperm for the fertilization of ova has led to the evolution of a diver- sity of characters in male reproductive behaviour, physiology and morphology. Males may increase sperm competition success either by enhancing the success of their own sperm or by negating or eliminating the success of rival sperm. Here, we ¢nd that in the £our

E. Haubruge; L. Arnaud; J. Mignon; M. J. G. Gage

1999-01-01

119

Sperm: seminal fluid interactions and the adjustment of sperm quality in relation to female attractiveness  

PubMed Central

An important predictor of male fitness is the fertilizing efficiency of their ejaculates. Ejaculates are costly to produce and males are predicted to devote greater resources to copulations with reproductively superior females. It is well established that males allocate different numbers of sperm to ejaculates. However, less is known about how males adjust their sperm quality, which has important implications for our understanding of fertilization and the evolution of sexual strategies. Here we test in the fowl, Gallus gallus, whether males adjust their sperm velocity by differentially allocating seminal fluid to copulations with attractive and unattractive females. To disentangle the contributions of sperm and seminal fluid to sperm velocity, we separated and remixed sperm and seminal fluid from ejaculates allocated to females of different attractiveness. We show that dominant males increase the velocity of the sperm they invest in more attractive females by allocating larger ejaculates that contain seminal fluid that increases sperm velocity. Furthermore, we find weak evidence that males also allocate sperm with higher velocity, irrespective of seminal fluid, to more attractive females. PMID:19586951

Cornwallis, Charlie K.; O'Connor, Emily A.

2009-01-01

120

Sperm competition and sperm midpiece size: no consistent pattern in passerine birds  

PubMed Central

Sperm competition is thought to be a major force driving the evolution of sperm shape and function. However, previous studies investigating the relationship between the risk of sperm competition and sperm morphometry revealed inconclusive results and marked differences between taxonomic groups. In a comparative study of two families of passerines (Fringillidae and Sylviidae) and also across species belonging to different passerine families, we investigated the relative importance of the phylogenetic background on the relationship between sperm morphometry and the risk of sperm competition. The risk of sperm competition was inferred from relative testis mass as an indicator of investment in sperm production. We found: (i) a significant positive association between both midpiece length and flagellum length and relative testis mass in the Fringillidae, (ii) a significant negative association between sperm trait dimensions and relative testis mass in the Sylviidae, and (iii) no association across all species. Despite the striking difference in the patterns shown by the Sylviidae and the Fringillidae, the relationship between midpiece length and flagellum length was positive in both families and across all species with positive allometry. Reasons for the differences and similarities between passerine families are discussed. PMID:17476777

Immler, Simone; Birkhead, Tim R

2006-01-01

121

Ovarian fluid of receptive females enhances sperm velocity  

NASA Astrophysics Data System (ADS)

The females of several internal fertilizers are able to store sperm for a long time, reducing the risk of sperm limitation. However, it also means that males can attempt to mate outside females' receptive period, potentially increasing the level of sperm competition and exacerbating sexual conflict over mating. The guppy ( Poecilia reticulata), an internally fertilizing fish, is a model system of such competition and conflict. Female guppies accept courtship and mate consensually only during receptive periods of the ovarian cycle but receive approximately one (mostly forced) mating attempt per minute both during and outside their sexually receptive phase. In addition, females can store viable sperm for months. We expected that guppy females would disfavour sperm received during their unreceptive period, possibly by modulating the quality and/or quantity of the components present in the ovarian fluid (OF) over the breeding cycle. Ovarian fluid has been shown to affect sperm velocity, a determinant of sperm competition success in this and other fishes. We found that in vitro sperm velocity is slower in OF collected from unreceptive females than in OF from receptive females. Visual stimulation with a potential partner prior to collection did not significantly affect in vitro sperm velocity. These results suggest that sperm received by unreceptive females may be disfavoured as sperm velocity likely affects the migration process and the number of sperm that reach storage sites.

Gasparini, Clelia; Andreatta, Gabriele; Pilastro, Andrea

2012-05-01

122

Rapid adjustments of sperm characteristics in relation to social status  

PubMed Central

Sperm competition models predict that males typically mating in disfavoured roles should be selected to compensate for their disadvantage by investing more into sperm. We studied the effect of rapid changes in social status on ejaculate investments during experimental trials with an externally fertilizing teleost—the Arctic charr (Salvelinus alpinus). We document that males becoming dominant produce less sperm with lower velocity, but have higher sex steroid concentrations than subordinate males. These differences in sperm characteristics seem mainly to result from a decreased investment in sperm among fish that become dominant compared to pre-trial levels. Moreover, these adjustments of sperm production and sperm velocity seem not to be traded against sperm longevity. Our results support theoretical models of sperm competition, as males forced to mate in disfavoured roles seem to invest more into ejaculate quality than males in favoured roles. Additionally, we are the first to report that males, in a species with status-dependent shifts in reproductive tactics, have evolved rapid tactic specific adjustments of sperm production and sperm velocity corresponding to what could be predicted from their reproductive roles. PMID:16543175

Rudolfsen, Geir; Figenschou, Lars; Folstad, Ivar; Tveiten, Helge; Figenschou, Marie

2005-01-01

123

Age-dependent changes in sperm production, semen quality, and testicular volume in the black-footed ferret (Mustela nigripes).  

PubMed

The black-footed ferret (Mustela nigripes), which was extirpated from its native North American prairie habitat during the 1980s, is being reintroduced to the wild because of a successful captive-breeding program. To enhance propagation, the reproductive biology of this endangered species is being studied intensively. The typical life span of the black-footed ferret is approximately 7 yr. Female fecundity declines after 3 yr of age, but the influence of age on male reproduction is unknown. In this study, testis volume, seminal traits, sperm morphology, and serum testosterone were compared in 116 males from 1 to 7 yr of age living in captivity. Results demonstrated that testes volume during the peak breeding season was similar (P > 0.05) among males 1 to 5 yr of age, reduced (P < 0.05) among males 6 yr of age, and further reduced (P < 0.05) among males 7 yr of age. Motile sperm/ejaculate was similar in males 1 to 6 yr of age but diminished (P < 0.05) in those 7 yr of age. Males at 6 and 7 yr of age produced fewer (P < 0.05) structurally normal sperm than younger counterparts; however, serum testosterone concentrations were not reduced (P > 0.05) in older males. Histological comparison of testicular/epididymal tissue from 5- and 7-yr-old black-footed ferrets confirmed that the interval between these two ages may represent a transitional period to reproductive senescence. In summary, functional reproductive capacity of male black-footed ferrets exceeds that of females by at least 2 yr. Testes and seminal quality are indistinguishable among males 1 to 5 yr of age, with progressive reproductive aging occurring thereafter. PMID:10859258

Wolf, K N; Wildt, D E; Vargas, A; Marinari, P E; Kreeger, J S; Ottinger, M A; Howard, J G

2000-07-01

124

Region-wide impairment of Atlantic croaker testicular development and sperm production in the northern Gulf of Mexico hypoxic dead zone.  

PubMed

Recently evidence has been obtained for reproductive impairment in estuarine populations of Atlantic croaker exposed to seasonal hypoxia. However, it is not known whether a similar disruption of reproductive function occurs in croaker inhabiting a much larger hypoxic area, the extensive dead zone in coastal regions of the northern Gulf of Mexico extending from the Mississippi Delta to East Texas. Gonadal development in male Atlantic croaker collected in September 2008 at six sites in the dead zone was compared to that in male fish sampled from three reference sites east of the Mississippi Delta which do not experience persistent hypoxia. Croaker testes collected from the dead zone were at an earlier stage of spermatogenesis than those from the reference sites. Histological examination of the testes collected from the dead zone showed that their tubules had small lumens that contained very little sperm compared to the lumens of the reference fish. Overall, sperm production was 26.2% that of the control fish at the reference sites. This decrease in spermatogenesis at the dead zone sites was accompanied by an approximately 50% decrease in testicular growth compared to that in the reference fish. The results suggest that reproductive impairment can occur over regional scales in marine fish populations exposed to extensive seasonal hypoxia in dead zones with potential long-term impacts on population abundance. PMID:19931178

Thomas, Peter; Rahman, Md Saydur

2010-01-01

125

Sperm selection and genetic incompatibility: does relatedness of mates affect male success in sperm competition?  

PubMed Central

Sperm selection may be said to occur if females influence the relative success of ejaculates competing to fertilize their ova. Most evidence that female animals or their ova are capable of sperm selection relates to male genetic incompatibility, although relatively few studies focus on competition between conspecific males. Here I look for evidence of sperm selection with respect to relatedness of mates. Reduced fitness or inbreeding effects in offspring resulting from copulations between close relatives are well documented. If females are capable of sperm selection, they might therefore be expected to discriminate against the sperm of sibling males during sperm competition. I describe an experimental protocol designed to test for evidence of sperm selection while controlling for inbreeding effects. Using decorated field crickets (Gryllodes supplicans), I found that sibling males achieved lower fertilization success in competition with a male unrelated to the female than in competition with another sibling more frequently than expected by chance, although the mean paternity values did not differ significantly between treatments. The tendancy for sibling males to achieve relatively lower fertilization success in competition with males unrelated to the female could not be explained by the effects of increased ejaculate allocation, female control of sperm transfer or inbreeding. This study therefore provides some evidence in support of the idea that female insects (or their ova) may be capable of selection against sperm on the basis of genetic similarity of conspecific males.

Stockley, P.

1999-01-01

126

Human sperm DNA integrity in normal and abnormal semen samples and its correlation with sperm characteristics  

Microsoft Academic Search

Summary Reports indicate an increase in the incidence of DNA fragmentation in male factor infertility and its role in the outcome of assisted reproductive techniques (ART). However, reports are conflicting between the relationships of sperm DNA integrity with conventional semen parameters. We examined the relation- ship between conventional sperm parameters and DNA integrity using acridine orange (AO) test. The study

A. C. Varghese; F. M. Bragais; D. Mukhopadhyay; S. Kundu; M. Pal; A. K. Bhattacharyya; A. Agarwal

2009-01-01

127

Automatic evaluation of ram sperm morphometry.  

PubMed

This study was designed to develop a new method based on fluorescence microscopy and image analysis for the automatic assessment of sperm morphometry and to study separately the effect of drying and fixation on the parameters of head sperm morphometry in the ram. The study was divided into two experiments. In the first experiment, ejaculates from 25 adult males were collected using an artificial vagina, diluted and divided into four sample aliquots. The first was labeled directly with Hoechst 33342 (FRESH), and the others were processed as smears. Between smears, one group was directly labeled with Hoechst after air drying (DRIED), and the other were fixed either with glutaraldehyde (GLUT), or with methanol (MET), and labeled with Hoechst afterward. Digital images of the fluorescence-labeled sperm were recorded with a digital camera, and sperm heads were automatically captured and analyzed using the ImageJ program. The method used allowed a fast and automatic selection of most sperm heads for a given image with high precision. There was a general trend toward significant decrease in head length, width, area and perimeter of air-dried sperm compared with fresh sperm. On average, this decrease was of 4.1% in length, 4.3% in width, 9.1% in area, and 2.8% in perimeter. Between semen smears, fixation with glutaraldehyde significantly increased head sperm dimensions. The smears fixed with glutaraldehyde method is recommended for a more practical use than with fresh samples, providing better quality images than the other methods, and because the morphometric results obtained were more similar to the FRESH group than those of the DRIED and MET. In the second experiment, ejaculates from adult males were used to compare the sperm head morphometric results obtained with the new method developed (using the GLUT treatment as reference) with a more conventional CASMA method (semen smears stained with Hemacolor and processed with the ISAS commercial software, HEM). The GLUT method allowed the analysis of 100% of sperm, whereas only 93% of sperm could be analyzed using HEM. Spermatozoa displayed a bigger size when processed with HEM than with GLUT method in all primary sperm head morphometric parameters. A significant correlation was observed between the two methods used in this experiment for all morphometric size parameters. The new method developed allows automatic determination of sperm head morphometry in a reduced time, which facilitates its use in routine semen analysis. It was concluded that the automation of sperm morphometry is feasible using fluorescence microscopy and image analysis and that the effect of drying and fixation was less important than previously stated. PMID:22225689

Yániz, J L; Vicente-Fiel, S; Capistrós, S; Palacín, I; Santolaria, P

2012-04-15

128

Elevated frequencies of hyperhaploid sperm were detected in a man with a history of multiple aneuploid pregnancies  

SciTech Connect

The goal of this research is to determine the heritable risk associated with elevations in the proportion of hyperhaploid human sperm. A case family presented with a history of four aneuploid pregnancies: two with autosomal trisomies (47,+ 22 and 47, +15) which were non-viable and two children with sex chromosomal aneuploidies (47, XYY and Klinefelter syndrome, 47, XXY). The father consumed {approximately}{1/2} pack of cigarettes and 1 alcoholic drink per day. He had no notable occupational or environmental exposures. Paternal origin of extra X chromosomes in the boy with Klinefelter syndrome was confirmed by DNA analyses of blood using polymorphic X-linked microsatellite markers. The inheritance pattern was established by {ge}2 informative loci using PCR products analyzed on an automatic DNA sequencer. Multi-probe sperm FISH was employed to determine the proportion of sperm with aneuploidies involving chromosome 21, X, and Y. Sperm aneuploidy frequencies of hyper-haploid sperm; XY ({approximately}6 fold, p < 0.001), 21-21 ({approximately}6 fold, p< 0.001), XX and YY ({approximately}2 fold, p<0.02). These findings suggest that elevated proportions of aneuploid sperm may be associated with an increased risk of fathering an aneuploid offspring. These findings are also relevant for future studies of heritable risk for men with elevations in sperm aneuploidy after exposures to therapeutic or environmental agents.

Chuu, Y.J.; Wyrobek, A.J. [Lawrence Livermore National Lab., CA (United States); Kidd, S. [Univ. of California, Berkeley, CA (United States)] [and others

1997-10-01

129

Characterization of red-legged partridge (Alectoris rufa) sperm: Seasonal changes and influence of genetic purity.  

PubMed

The general decline in wild Iberian populations of the red-legged partridge (Alectoris rufa) has been accompanied by an increase in game-farm facilities producing hybrids with chukar partridges (Alectoris chukar). Genetic introgression from chukar partridges is thought to modify male red-legged partridge reproductive indicators. The aim of the present study was to determine the effects of such genetic introgression on seasonal reproductive patterns by comparing the sperm and plasma testosterone concentrations of males from pure red-legged and hybrid red-legged/chukar populations. Semen was collected twice monthly over a 12-mo period using a massage technique. Both types of bird showed a clear seasonal pattern of spermatogenic activity. The proportion of males ejaculating sperm was higher (P < 0.05) among the pure red-legged birds. The greatest sperm production was recorded in March to May among the pure birds and April to May among the hybrids. Reproductive activity in both groups decreased in June, to reach a minimum in August to December among the hybrids and in September to December among the pure birds. Spermatogenic activity resumed in January in both groups. The sperm concentration produced by the pure birds was smaller than that of the hybrids (P < 0.001), but the percentage of motile sperm was higher in the pure birds (P < 0.001). The sperm of the hybrids showed greater straight-line velocity (P < 0.05), linearity (P < 0.001), straightness (P < 0.001), sperm wobble (P < 0.05), and beat-cross frequency values (P < 0.001). The length and area of the sperm head were smaller in the pure birds (P < 0.05). The seasonal plasma testosterone concentration pattern followed a trend roughly parallel to the ejaculatory response. The present results suggest that genetic introgression influences the reproductive variables of the red-legged partridge. PMID:25577796

Santiago-Moreno, J; Castaño, C; Toledano-Díaz, A; Esteso, M C; López-Sebastián, A; Gañán, N; Hierro, M J; Marchal, F; Campo, J L; Blesbois, E

2015-01-01

130

Summer flounder (Paralichthys dentatus) sperm cryopreservation and application in interspecific hybridization with olive flounder (P olivaceus).  

PubMed

The present study established an efficient technology for summer flounder (Paralichthys dentatus) sperm cryopreservation, and successfully applied the cryopreserved sperm into interspecific hybridization with olive flounder (P olivaceus). The best motility of postthaw sperm (78.00 ± 4.70% and 76.60 ± 7.90%), fertilization rates (95.70 ± 3.60% and 79.40 ± 5.20%), and hatching rates (93.10 ± 4.00% and 77.20 ± 2.90%) were achieved when using propylene glycol or DMSO as cryoprotectant. Furthermore, we have successfully improved the cryopreservation method from using 2-mL cryotube to 5-mL cryotube, and the dilution ratio has been increased to 4:1. By this method, the cryopreservation efficiency has been improved to 30 times of that with routine method. Computer-assisted sperm motion analysis showed the freezing-thawing process decreased the sperm speed but did not significantly change the sperm movement pattern, and the progressive linear motion still was the dominant movement pattern. The ultrastructural analysis showed 50% to 60% of the spermatozoa had normal morphology, 20% to 30% were slightly damaged, such as swelling or rupture of head, midpiece, and tail region, and 10% to 20% were severely damaged. In the artificial hybridization experiment, high fertilization rates and hatching rates were achieved when using 15% DMSO (95.7 ± 3.6% and 79.4 ± 5.2%, respectively) and 15% propylene glycol (93.1 ± 4.0% and 77.2 ± 2.9%, respectively), with no significant difference in comparison with control (94.7 ± 2.6% and 72.5 ± 6.5%, respectively). In addition, we found the embryos and larvae from postthaw sperm of P dentatus developed and grew normally. The results of the present study further validated the safety of the cryopreserved sperm in breeding production by assessing the fertilization capacity, embryo development, and larval growth. PMID:25476822

Liu, Q H; Ma, D Y; Xu, S H; Xiao, Z Z; Xiao, Y S; Song, Z C; Li, J

2015-03-01

131

The dynamics of sperm cooperation in a competitive environment.  

PubMed

Sperm cooperation has evolved in a variety of taxa and is often considered a response to sperm competition, yet the benefit of this form of collective movement remains unclear. Here, we use fine-scale imaging and a minimal mathematical model to study sperm aggregation in the rodent genus Peromyscus. We demonstrate that as the number of sperm cells in an aggregate increase, the group moves with more persistent linearity but without increasing speed. This benefit, however, is offset in larger aggregates as the geometry of the group forces sperm to swim against one another. The result is a non-monotonic relationship between aggregate size and average velocity with both a theoretically predicted and empirically observed optimum of six to seven sperm per aggregate. To understand the role of sexual selection in driving these sperm group dynamics, we compared two sister-species with divergent mating systems. We find that sperm of Peromyscus maniculatus (highly promiscuous), which have evolved under intense competition, form optimal-sized aggregates more often than sperm of Peromyscus polionotus (strictly monogamous), which lack competition. Our combined mathematical and experimental study of coordinated sperm movement reveals the importance of geometry, motion and group size on sperm velocity and suggests how these physical variables interact with evolutionary selective pressures to regulate cooperation in competitive environments. PMID:25056618

Fisher, Heidi S; Giomi, Luca; Hoekstra, Hopi E; Mahadevan, L

2014-09-01

132

The dynamics of sperm cooperation in a competitive environment  

E-print Network

Sperm cooperation has evolved in a variety of taxa and is often considered a response to sperm competition, yet the benefit of this form of collective movement remains unclear. Here we use fine-scale imaging and a minimal mathematical model to study sperm aggregation in the rodent genus $Peromyscus$. We demonstrate that as the number of sperm cells in an aggregate increase, the group moves with more persistent linearity but without increasing speed; this benefit, however, is offset in larger aggregates as the geometry of the group forces sperm to swim against one another. The result is a non-monotonic relationship between aggregate size and average velocity with both a theoretically predicted and empirically observed optimum of 6-7 sperm/aggregate. To understand the role of sexual selection in driving these sperm group dynamics, we compared two sister-species with divergent mating systems and find that sperm of $P.\\,maniculatus$ (highly promiscuous), which have evolved under intense competition, form optimal-sized aggregates more often than sperm of $P.\\,polionotus$ (strictly monogamous), which lack competition. Our combined mathematical and experimental study of coordinated sperm movement reveals the importance of geometry, motion and group size on sperm velocity and suggests how these physical variables interact with evolutionary selective pressures to regulate cooperation in competitive environments.

H. S. Fisher; L. Giomi; H. E. Hoekstra; L. Mahadevan

2014-07-02

133

The dynamics of sperm cooperation in a competitive environment  

PubMed Central

Sperm cooperation has evolved in a variety of taxa and is often considered a response to sperm competition, yet the benefit of this form of collective movement remains unclear. Here, we use fine-scale imaging and a minimal mathematical model to study sperm aggregation in the rodent genus Peromyscus. We demonstrate that as the number of sperm cells in an aggregate increase, the group moves with more persistent linearity but without increasing speed. This benefit, however, is offset in larger aggregates as the geometry of the group forces sperm to swim against one another. The result is a non-monotonic relationship between aggregate size and average velocity with both a theoretically predicted and empirically observed optimum of six to seven sperm per aggregate. To understand the role of sexual selection in driving these sperm group dynamics, we compared two sister-species with divergent mating systems. We find that sperm of Peromyscus maniculatus (highly promiscuous), which have evolved under intense competition, form optimal-sized aggregates more often than sperm of Peromyscus polionotus (strictly monogamous), which lack competition. Our combined mathematical and experimental study of coordinated sperm movement reveals the importance of geometry, motion and group size on sperm velocity and suggests how these physical variables interact with evolutionary selective pressures to regulate cooperation in competitive environments. PMID:25056618

Fisher, Heidi S.; Giomi, Luca; Hoekstra, Hopi E.; Mahadevan, L.

2014-01-01

134

Four products from Escherichia coli pseudogenes increase hydrogen production.  

PubMed

Pseudogenes are considered to be nonfunctional genes that lack a physiological role. By screening 3985 Escherichia coli mutants using chemochromic membranes, we found four pseudogenes involved in hydrogen metabolism. Knockouts of pseudogenes ydfW and ypdJ had a defective hydrogen phenotype on glucose and formate, respectively. Also, the knockout of pseudogene yqiG formed hydrogen from formate but not from glucose. For the yqiG mutant, 100% hydrogen recovery was obtained by the complementation of YqiG via a plasmid. The knockout of pseudogene ylcE showed hydrogen deficiency in minimal media which suggested that the role of YlcE is associated with cell growth. Hence, the products of these four pseudogenes play an important physiological role in hydrogen production in E. coli. PMID:24025676

Mohd Yusoff, Mohd Zulkhairi; Hashiguchi, Yuya; Maeda, Toshinari; Wood, Thomas K

2013-10-01

135

Observation of sperm-head vacuoles and sperm morphology under light microscope  

PubMed Central

Objective The presence of sperm-head vacuoles has been suspected to be deleterious to the outcomes of assisted reproductive technology (ART). It is difficult to accurately distinguish morphologically abnormal sperm with vacuoles under a light microscope. This study was performed to analyze the result of the observation of sperm-head vacuoles using Papanicolaou staining under a light microscope and whether the male partner's age affects these vacuoles. Methods Sperm morphology with vacuoles was evaluated using Papanicolaou staining and observed under a light microscope (400×) in 980 men. The normal morphology was divided into three categories (group A, <4% of normal morphology; group B, 4%-14% of normal morphology; and group C, >14% of normal morphology). The criteria for the sperm-head vacuoles were those given in the World Health Organization manual. For the analysis of the age factor, the participants were divided into the following groups: 26-30 years, 31-35 years, 36-40 years, 41-45 years, and 46-50 years. Results The percentage of sperm-head vacuoles increased with normal sperm morphology (group A vs. groups B, C) (p<0.05). In the case of the age factor, a statistically significant difference was not observed across any of the age groups. Conclusion A majority of the sperm-head vacuoles showed a statistically significant difference among normal morphology groups. Therefore, we should consider the probability of the percentage of sperm-head vacuoles not increasing with age but with abnormal sperm morphology. A further study is required to clarify the effect of the sperm-head vacuoles on ART outcomes. PMID:25309858

Park, Sol; Ko, Duck Sung; Park, Dong Wook; Yang, Kwang Moon

2014-01-01

136

Quantifying Energy Savings from Lean Manufacturing Productivity Increases  

E-print Network

practice. As such, accepted methods used to calculate energy savings from productivity improvements are not prevalent. This paper will first review several existing energy efficiency programs that promote manufacturing productivity increases...: Northeast Utilities’ PRIME Program and the DOE Industrial Assessment Centers. In conjunction, this paper will review the methods used to quantify energy savings for each program. Additionally, the relationship between productivity improvements...

Seryak, J.; Epstein, G.; D'Antonio, M.

2006-01-01

137

Effects of cholesterol-loaded cyclodextrins on the quality of frozen-thawed equine epididymal sperm.  

PubMed

Equine epididymal sperm are known to be severely sensitive to cryopreservation, in terms of sperm quality and pregnancy rate. The objective of this study was to examine the effects of cholesterol loaded cyclodextrins (CLCs) on the quality of stallion epididymal sperm during cryopreservation. In experiment I, sperm were treated with different concentrations of CLCs: (1) 0mg (control), (2) 1.5mg, (3) 3mg, and (4) 6 mg per 120 × 10(6) sperm. The sperm viability and amount of cholesterol were determined at 15, 30 and 45 min after CLC treatment using viability markers (Ethidium homodimer-1 and Calcein AM) and gas chromatography, respectively. In experiment II, CLC treated sperm (1.5mg CLC per 120 × 10(6) sperm) were fixed and stained with filipin to examine the cholesterol distribution. In experiment III, sperm were treated with CLCs at concentrations of 1.5, 3.0, 6.0 mg per 120 × 10(6) sperm for 15 min, then equilibrated with freezing extender at 4°C for 1h prior to cryopreservation. Epididymal sperm without CLC loading (0mg) were used as the control group. The sperm quality was examined at post-equilibration and 10 min, 2h and 4h after freezing and thawing. The cholesterol was successfully loaded into the plasma membrane of stallion epididymal sperm. The amount of cholesterol was increased in a manner of dose and time dependence, and the filipin-sterol complexes were increasingly labeled over the sperm head. CLCs at 1.5mg/120 × 10(6) sperm significantly improved sperm quality during sperm equilibration and cryopreservation compared to other doses of CLCs and non-CLC control. An increasing concentration and incubation time of CLCs was detrimental to sperm quality. It is concluded that cholesterol loading to the sperm plasma membrane via CLCs decreases chilling sensitivity and also improves epididymal sperm cryopreservability. PMID:21679702

Pamornsakda, Teeraporn; Pojprasath, Thanakorn; Suwimonteerabutr, Junpen; Tharasanit, Theerawat

2011-10-01

138

Effects of metronidazole, ipronidazole, and dibromochloropropane on rabbit and human sperm motility and fertility.  

PubMed

Treatment of protozoal pathogens in the reproductive system with chemical agents exposes flagellated sperm cells to potential toxicants. A widely used antiprotozoal agent is metronidazole. Its effect on rabbit and human sperm was compared with a more soluble 5-nitroazole compound, ipronidazole, and with a systemic environmental toxicant, dibromochloropropane (DBCP). The percentages of motile rabbit and human sperm incubated with the compounds, the velocity of sperm, migration of sperm in polyacrylamide gel, young born in rabbits, and penetration of hamster oocytes by treated human sperm were measured in seven experiments. Up to 10mg/ml metronidazole and 1mg/ml DBCP had little effect on most sperm characteristics. However, 10mg/ml metronidazole and 5mg/ml of ipronidazole increased attachment of human sperm to hamster oocytes, but oocyte penetration was unaffected. Rabbit sperm exposed to 5mg/ml ipronidazole were infertile. No oocytes were penetrated by DBCP-treated human sperm. PMID:12401502

Foote, Robert H

2002-01-01

139

Ethanol extract of the leaves of Psidium guajava Linn enhances sperm output in healthy Wistar rats.  

PubMed

Reactive oxygen species (ROS), among other factors, have been implicated in the aetiology of male infertility. Thus, the roles of antioxidants at improving sperm production and quality are being investigated. The present study was designed to assess the effect of the ethanol extract of fresh leaves of Psidium guajava Linn. on the sperm parameters of healthy male Wistar rats. A total of 18 rats, weighing between 108-124 g, were divided into 3 groups of 6 animals each. Animals in groups 1 and 2 were administered 250 mg/kg/d and 500 mg/kg/d of guava leaf extract (GLE) orally for 53 days respectively. Group 3 animals received normal saline. Sperm count increased from 56.2+/-0.3 (x10(6)) in the control to 57.1+/-0.2 (x10(6)) in group 1 animals, and from 56.2+/-0.3 (x10(6)) in the control to 72.3+/-0.4 (x10(6)) in group 2 animals. Similarly, dose-dependent increases in the percentages of motile spermatozoa were observed in GLE-treated animals compared to the control group. These findings suggest that the extracts of the leaves of Psidium guajava Linn. possess beneficial effects on sperm production and quality, and may thus improve the sperm parameters of infertile males with oligospermia and nonobstructive azoospermia. PMID:19205576

Akinola, O B; Oladosu, O S; Dosumu, O O

2007-06-01

140

Oxidative Stress in Zebrafish (Danio rerio) Sperm  

PubMed Central

Laboratories around the world have produced tens of thousands of mutant and transgenic zebrafish lines. As with mice, maintaining all of these valuable zebrafish genotypes is expensive, risky, and beyond the capacity of even the largest stock centers. Because reducing oxidative stress has become an important aspect of reducing the variability in mouse sperm cryopreservation, we examined whether antioxidants might improve cryopreservation of zebrafish sperm. Four experiments were conducted in this study. First, we used the xanthine-xanthine oxidase (X-XO) system to generate reactive oxygen species (ROS). The X-XO system was capable of producing a stress reaction in zebrafish sperm reducing its sperm motility in a concentration dependent manner (P<0.05). Second, we examined X-XO and the impact of antioxidants on sperm viability, ROS and motility. Catalase (CAT) mitigated stress and maintained viability and sperm motility (P>0.05), whereas superoxide dismutase (SOD) and vitamin E did not (P<0.05). Third, we evaluated ROS in zebrafish spermatozoa during cryopreservation and its effect on viability and motility. Methanol (8%) reduced viability and sperm motility (P<0.05), but the addition of CAT mitigated these effects (P>0.05), producing a mean 2.0 to 2.9-fold increase in post-thaw motility. Fourth, we examined the effect of additional cryoprotectants and CAT on fresh sperm motility. Cryoprotectants, 8% methanol and 10% dimethylacetamide (DMA), reduced the motility over the control value (P<0.5), whereas 10% dimethylformamide (DMF) with or without CAT did not (P>0.05). Zebrafish sperm protocols should be modified to improve the reliability of the cryopreservation process, perhaps using a different cryoprotectant. Regardless, the simple addition of CAT to present-day procedures will significantly improve this process, assuring increased and less variable fertilization success and allowing resource managers to dependably plan how many straws are needed to safely cryopreserve a genetic line. PMID:22724013

Hagedorn, Mary; McCarthy, Megan; Carter, Virginia L.; Meyers, Stuart A.

2012-01-01

141

Cryopreservation of Sperm from the Endangered Colorado Pikeminnow  

USGS Publications Warehouse

We developed methods for the cryopreservation of sperm of the endangered Colorado pikeminnow Ptychocheilus lucius. Sperm were collected from a captive broodstock population of Colorado pikeminnow reared and maintained at the Dexter National Fish Hatchery and Technology Center. Our objectives were to (1) evaluate the effects on sperm motility of 24-h storage in Hanks' balanced salt solution (HBSS); (2) characterize sperm motility and duration; (3) examine the relationship between sperm motility and osmotic pressure; (4) examine the effect of four cryoprotectants (dimethyl sulfoxide [DMSO], dimethyl acetamide [DMA], glycerol, and methanol [MeOH] at two concentrations [5% and 10%]) on postthaw motility; and (5) compare the effect of two cooling rates (40??C/ min and 4??C/min) on postthaw motility. The sperm samples diluted with HBSS retained higher motility (mean ??SD, 77 ?? 22%; n = 9) than did undiluted samples (12 ?? 30%; n = 9) after 24 h of storage. When exposed to HBSS at 274 mosmols/kg or more, few sperm became motile (???1%). Exposure to HBSS at 265 mosmols/kg elicited threshold activation (defined as 10% motility), and maximum motility (>95%) was observed at 93 mosmols/ kg. The maximum motility of sperm was observed within 10 s after activation with deionized water, and sperm remained motile for 57 s. The sperm that were cooled at a rate of 40??C/min and cryopreserved with 5% MeOH retained higher postthaw motility (56 ?? 13%) than did sperm cryopreserved with DMSO, DMA, or glycerol (at 5% and 10%). When the sperm samples were cooled at a rate of 4??C/min, sperm cryopreserved with MeOH (5% or 10%) or DMSO (5% or 10%) retained the highest postthaw motilities (???14%). The use of cryopreserved sperm can assist hatchery managers in the production of fish, provide for the long-term conservation of genetic resources, and assist in the recovery of endangered species such as the Colorado pikeminnow.

Tiersch, T.R.; Figiel, C.R., Jr.; Wayman, W.R.; Williamson, J.H.; Gorman, O.T.; Carmichael, G.J.

2004-01-01

142

Male mammals respond to a risk of sperm competition conveyed by odours of conspecific males.  

PubMed

Sperm competition occurs when a female copulates with two or more males and the sperm of those males compete within the female's reproductive tract to fertilize her eggs. The frequent occurrence of sperm competition has forced males of many species to develop different strategies to overcome the sperm of competing males. A prevalent strategy is for males to increase their sperm investment (total number of sperm allocated by a male to a particular female) after detecting a risk of sperm competition. It has been shown that the proportion of sperm that one male contributes to the sperm pool of a female is correlated with the proportion of offspring sired by that male. Therefore, by increasing his sperm investment a male may bias a potential sperm competition in his favour. Here we show that male meadow voles, Microtus pennsylvanicus, increase their sperm investment when they mate in the presence of another male's odours. Such an increase in sperm investment does not occur by augmenting the frequency of ejaculations, but by increasing the amount of sperm in a similar number of ejaculations. PMID:15386011

Delbarco-Trillo, Javier; Ferkin, Michael H

2004-09-23

143

Male mammals respond to a risk of sperm competition conveyed by odours of conspecific males  

NASA Astrophysics Data System (ADS)

Sperm competition occurs when a female copulates with two or more males and the sperm of those males compete within the female's reproductive tract to fertilize her eggs. The frequent occurrence of sperm competition has forced males of many species to develop different strategies to overcome the sperm of competing males. A prevalent strategy is for males to increase their sperm investment (total number of sperm allocated by a male to a particular female) after detecting a risk of sperm competition. It has been shown that the proportion of sperm that one male contributes to the sperm pool of a female is correlated with the proportion of offspring sired by that male. Therefore, by increasing his sperm investment a male may bias a potential sperm competition in his favour. Here we show that male meadow voles, Microtus pennsylvanicus, increase their sperm investment when they mate in the presence of another male's odours. Such an increase in sperm investment does not occur by augmenting the frequency of ejaculations, but by increasing the amount of sperm in a similar number of ejaculations.

delBarco-Trillo, Javier; Ferkin, Michael H.

2004-09-01

144

Rheotaxis guides mammalian sperm  

PubMed Central

Background In sea urchins, spermatozoan motility is altered by chemotactic peptides, giving rise to the assumption that mammalian eggs also emit chemotactic agents that guide spermatozoa through the female reproductive tract to the mature oocyte. Mammalian spermatozoa indeed undergo complex adaptations within the female (the process of capacitation) that are initiated by agents ranging from pH to progesterone, but these factors are not necessarily taxic. Currently, chemotaxis, thermotaxis, and rheotaxis have not been definitively established in mammals. Results Here, we show that positive rheotaxis, the ability of organisms to orient and swim against the flow of surrounding fluid, is a major taxic factor for mouse and human sperm. This flow is generated within 4 hours of sexual stimulation and coitus in female mice; prolactin-triggered oviductal fluid secretion clears the oviduct of debris, lowers viscosity, and generates the stream that guides sperm migration in the oviduct. Rheotaxic movement is demonstrated in capacitated and uncapacitated spermatozoa in low and high viscosity medium. Finally, we show that a unique sperm motion we quantify using the sperm head's rolling rate reflects sperm rotation that generates essential force for positioning the sperm in the stream. Rotation requires CatSper channels, presumably by enabling Ca2+ influx. Conclusions We propose that rheotaxis is a major determinant of sperm guidance over long distances in the mammalian female reproductive tract. Coitus induces fluid flow to guide sperm in the oviduct. Sperm rheotaxis requires rotational motion during CatSper channel-dependent hyperactivated motility. PMID:23453951

Miki, Kiyoshi; Clapham, David E

2013-01-01

145

Modernization and optimization of irrigation systems to increase water productivity  

Microsoft Academic Search

Population increase and the improvement of living standards brought about by development will result in a sharp increase in food demand during the next decades. Most of this increase will be met by the products of irrigated agriculture. At the same time, the water input per unit irrigated area will have to be reduced in response to water scarcity and

Enrique Playán; Luciano Mateos

2004-01-01

146

Neurotensin enhances sperm capacitation and acrosome reaction in mice.  

PubMed

Neurotensin (NT) has multiple functions, ranging from acting as a neurotransmitter to regulating intestinal movement. However, its function in reproductive physiology is unknown. Here, we confirmed the expression and localization of NT receptors (NTR1) in mouse epididymal spermatozoa and investigated the effect of NT on sperm function. Sperm protein tyrosine phosphorylation, one of the indices of sperm capacitation, was facilitated dose-dependently by NT administration. In addition, the acrosome reaction was promoted in capacitated spermatozoa, and addition of a selective antagonist of NTR1 and NTR2 blocked the induction. Furthermore, intracellular calcium mobilization by NT addition was observed. This showed that NT was an accelerator of sperm function via its functional receptors. The presence of NT was confirmed by immunohistochemistry and its localization was observed in epithelia of the uterus and oviduct isthmus and ampulla, which correspond to the fertilization route of spermatozoa. The NT mRNA level in ovulated cumulus cell was remarkably increased by treatment with human chorionic gonadotropin (hCG). Using an in vitro maturation model, we analyzed the effects of FSH, epidermal growth factor (EGF), estradiol, and progesterone in NT production in cumulus cells. We found that FSH and EGF upregulated NT release and mRNA expression. Both FSH- and EGF-induced upregulation were inhibited by U0126, an MAPK kinase inhibitor, indicating that FSH and EGF regulate NT expression via a MAPK-dependent pathway. This evidence suggests that NT can act as a promoter of sperm capacitation and the acrosome reaction in the female reproductive tract. PMID:25031361

Hiradate, Yuuki; Inoue, Hiroki; Kobayashi, Norio; Shirakata, Yoshiki; Suzuki, Yutaka; Gotoh, Aina; Roh, Sang-Gun; Uchida, Takafumi; Katoh, Kazuo; Yoshida, Manabu; Sato, Eimei; Tanemura, Kentaro

2014-08-01

147

Human sperm chromosome analysis after subzonal sperm insemination of hamster oocytes  

SciTech Connect

Sperm microinjection techniques, subzonal sperm insemination (SUZI) and intracytoplasmic sperm injection (ICSI), have achieved a wide spread clinical application for the treatment of male infertility. To date, only one study has focused on sperm karyotypes after microinjection. Martin et al. reported a very high incidence of abnormal human sperm complements after ICSI into hamster oocytes. In the present study, are reported the first human sperm karyotypes after SUZI of hamster oocytes. Spermatozoa from two control donors were treated by calcium ionophore A23187 and injected under the zona of hamster eggs. The microinjected eggs were then cultured for cytogenetic analysis of the pronuclei. Out of 47 analyzed sperm chromosome metaphases, 5 (10.6%) were abnormal, 4 (8.5%) were hypohaploid and 1 (2.1%) had a structural abnormality. The sex ratio was not significantly different from the expected 1:1 ratio. Rates of chromosomal abnormalities in microinjected spermatozoa were similar to those observed in spermatozoa inseminated with zona free eggs, suggesting that SUZI procedure per se does not increase sperm chromosomal abnormalities.

Cozzi, J. [Medical School of Grenoble (France)

1994-09-01

148

Productivity increase of the vertical roller mill for cement grinding  

Microsoft Academic Search

The specific power consumption, product quality and other performance of the “OK” and “CK” vertical roller mills for cement grinding are briefly stated. Hence, the enhancement in increasing the productivity of the vertical roller mill at Chichibu Onoda Cement Corporation (COCC) is introduced. These include: (a) restoring a table liner and roller tires by hard-facing to reduce maintenance costs; (b)

M. Ito; K. Sato; Y. Naoi

1997-01-01

149

Sperm chromatin condensation, DNA integrity, and apoptosis in men with spinal cord injury  

PubMed Central

Objectives To evaluate the effect of cord injury on (1) sperm parameters and (2) DNA chromatin status. Design Case–control study. Setting Data were collected from men referred to Research and Clinical Center for Infertility, Yazd, Iran. Participants Thirty infertile men with the presence of any level of spinal cord injury (SCI) were compared with 30 healthy donors with definite fertility and normal sperm parameters. Interventions Not applicable. Outcome measures Sperm chromatin integrity was assessed using aniline blue (AB), chromomycin A3 (CMA3), toluidine blue (TB), and acridine orange (AO) assays. The rate of apoptotic spermatozoa was evaluated with terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling (TUNEL) staining. Results Sperm concentration, motility, and morphology in men with SCI were significantly decreased compared with control group (P < 0.05). In addition, with regard to cytochemical staining and TUNEL test, the rate of reacted spermatozoa was increased significantly in SCI group when compared with the controls (P < 0.05). The majority of AB, TB, AO, and CMA3-reacted spermatozoa were higher than the “cut-off” value in men with SCI, as were the number of apoptotic spermatozoa stained with TUNEL. Conclusion Results showed that SCI disturbs sperm parameters, nuclear maturity, and DNA integrity of spermatozoa. Therefore, the production of spermatozoa with less condensed chromatin and more apoptotic rate increases after cord injury and this may be one possible cause of infertility following SCI. PMID:23809529

Talebi, Ali Reza; Khalili, Mohammad Ali; Vahidi, Serajodin; Ghasemzadeh, Jalal; Tabibnejad, Nasim

2013-01-01

150

Sperm Patch-Clamp  

PubMed Central

Sperm intracellular pH and calcium concentration ([Ca2+]i) are two central factors that control sperm activity within the female reproductive tract. As such, the ion channels of the sperm plasma membrane that alter intracellular sperm [Ca2+] and pH play important roles in sperm physiology and the process of fertilization. Indeed, sperm ion channels regulate sperm motility, control sperm chemotaxis toward the egg in some species, and may trigger the acrosome reaction. Until recently, our understanding of these important molecules was rudimentary due to the inability to patch-clamp spermatozoa and directly record the activity of these ion channels under voltage clamp. Recently, we overcame this technical barrier and developed a method for reproducible application of the patch-clamp technique to mouse and human spermatozoa. This chapter covers important aspects of application of the patch-clamp technique to spermatozoa, such as selection of the electrophysiological equipment, isolation of spermatozoa for patch-clamp experiments, formation of the gigaohm seal with spermatozoa, and transition into the whole-cell mode of recording. We also discuss potential pitfalls in application of the patch-clamp technique to flagellar ion channels. PMID:23522465

Lishko, Polina; Clapham, David E.; Navarro, Betsy; Kirichok, Yuriy

2014-01-01

151

Sperm motility under conditions of weightlessness.  

PubMed

The aim of this study was to determine the differences in motility of frozen and thawed bull spermatozoa under conditions of weightlessness compared with ground conditions. The tests were performed within a series of scientific and technologic experiments under microgravity using sounding rockets in the Technologische Experimente unter Schwerelosigkeit (TEXUS) program launched in Kiruna, North Sweden. Using a computerized sperm motility analyzer, significant differences were found in sperm motility under microgravity compared with sperm under gravitational conditions on earth. Computer analysis showed alterations in straight line and curvilinear velocity, as well as in linearity values. The amount of progressively motile spermatozoa, including all spermatozoa with a velocity > 20 microns/second, increased significantly from 24% +/- 9.5% in the reference test to 49% +/- 7.6% in the microgravity test. In conclusion, there is strong evidence that gravity influences sperm motility. PMID:1429219

Engelmann, U; Krassnigg, F; Schill, W B

1992-01-01

152

Sperm size of African cichlids in relation to sperm competition  

Microsoft Academic Search

We compared pairs of closely related taxa of cichlid fishes from Lake Tanganyika to examine the relationship between sperm size and the presumed intensity of sperm competition. In contrast to previous reports of relatively short sperm in polygamous fishes across a variety of taxa, we found that polygamous cichlids had significantly longer sperm than their closest monogamous relatives. In addition,

Sigal Balshine; Brenda J. Leach; Francis Neat; Noam Y. Werner; Robert Montgomerieb

2001-01-01

153

Suprazero Cooling Rate, Rather Than Freezing Rate, Determines Post Thaw Quality Of Rhesus Macaque Sperm  

PubMed Central

Sperm become most sensitive to cold shock when cooled from 37ºC to 5ºC at rates that are too fast or too slow; cold shock increases the susceptibility to oxidative damage due to its influence on reactive oxygen species (ROS) production ([1]. ROS are significant stress factors that are generated during cooling and low temperature storage, and may be a main cause of decreased motility and fertility upon warming. ROS have been shown to change cellular function through the disruption of the sperm plasma membrane and through damage to proteins and DNA. The objective of this study was to determine which cryopreservation rates result in the lowest degree of oxidative damage and greatest sperm quality. In the rhesus model it has not been determined whether suprazero cooling or subzero freezing rates causes a significant amount of ROS damage to sperm. Semen samples were collected from male rhesus macaques, washed, and resuspended in TEST-yolk cryopreservation buffer to 100 x 106 sperm/mL. Sperm were frozen in 0.5mL straws at four different combinations of suprazero and subzero rates. Three different suprazero rates were used between 22ºC and 0ºC: 0.5ºC/min (Slow), 45ºC/min (Medium), and 93ºC/min (Fast). These suprazero rates were used in combination with two different subzero rates for temperatures 0ºC to ?110ºC: 42ºC/min (Medium) and 87ºC/min (Fast). The different freezing groups were as follows: Slow-Med (SM), Slow-Fast (SF), Med-Med (MM), and Fast-Fast (FF). Flow cytometry was used to detect lipid peroxidation (LPO), a result of ROS generation. Motility was evaluated using a computer assisted sperm motion analyzer. The MM and FF treated sperm had less viable (P < 0.0001) and motile sperm (P < 0.001) than the SM, SF, or fresh sperm. Sperm exposed to MM and FF treatments demonstrated significantly higher oxidative damage than SM, SF, or fresh sperm (P < 0.05). The SM and SF treated sperm showed decreased motility, membrane integrity, and LPO compared to fresh semen (P<0.001). Slow cooling from room temperature promotes higher membrane integrity and motility post thaw, compared to medium or fast cooling rates. Cells exposed to similar cooling rates with differing freezing rates were not different in motility and membrane integrity, whereas comparison of cells exposed to differing cooling rates with similar freezing rates indicated significant differences in motility, membrane integrity, and LPO. These data suggest that sperm quality appears to be more sensitive to the cooling, rather than freezing rate and highlight the role of the suprazero cooling rate in post thaw sperm quality. PMID:24239181

Martorana, Kelly; Klooster, Katie; Meyers, Stuart

2013-01-01

154

Foresight — balancing between increasing variety and productive convergence  

Microsoft Academic Search

Extensive involvement of social actors and perspectives is an increasing trend in foresight. Simultaneously, however, the theoretical literature suggests that there is a trade-off between increasing variety and productive convergence. The paper examines, through a sample of recent foresight exercises, how European foresight balances between variety and convergence. The findings support the existence of a trade-off, and suggest that it

Mikko Rask

2008-01-01

155

A Systematic Analysis of a Deep Mouse Epididymal Sperm Proteome  

SciTech Connect

Spermatozoa are highly specialized cells that, when mature, are capable of navigating the female reproductive tract and fertilizing an oocyte. The sperm cell is thought to be largely quiescent in terms of transcriptional and translational activity. As a result, once it has left the male reproductive tract, the sperm cell is essentially operating with a static population of proteins. It is therefore theoretically possible to understand the protein networks contained in a sperm cell and to deduce its cellular function capabilities. To this end we have performed a proteomic analysis of mouse sperm isolated from the cauda epididymis and have confidently identified 2,850 proteins, which is the most comprehensive sperm proteome for any species reported to date. These proteins comprise many complete cellular pathways, including those for energy production via glycolysis, ?-oxidation and oxidative phosphorylation, protein folding and transport, and cell signaling systems. This proteome should prove a useful tool for assembly and testing of protein networks important for sperm function.

Chauvin, Theodore; Xie, Fang; Liu, Tao; Nicora, Carrie D.; Yang, Feng; Camp, David G.; Smith, Richard D.; Roberts, Kenneth P.

2012-12-21

156

Elemental composition of human semen is associated with motility and genomic sperm defects among older men  

PubMed Central

BACKGROUND Older men tend to have poorer semen quality and are generally at higher risks for infertility and abnormal reproductive outcomes. METHODS We employed proton-induced X-ray emission (PIXE, 3 MeV proton beam) to investigate the concentrations of zinc, copper, calcium, sulfur, chlorine, potassium, titanium, iron and nickel in washed sperm and seminal plasma from non-smoking groups of 10 older men (65–80 years old) and 10 younger men (22–28 years old) who were concurrently assayed for sperm function and genomicly defective sperm. RESULTS The older group showed elevated zinc, copper and calcium in sperm and elevated sulfur in seminal plasma compared with the younger men. The older group also showed reduced motility as well as increased sperm DNA fragmentation, achondroplasia mutations, DNA strand breaks and chromosomal aberrations. Sperm calcium and copper were positively associated with sperm DNA fragmentation (P < 0.03). Seminal sulfur was positively associated with sperm DNA fragmentation and chromosomal aberrations (P < 0.04), and negatively associated with sperm motility (P < 0.05). Sperm calcium was negatively associated with sperm motility, independent of male age (P = 0.01). CONCLUSIONS We identified major differences in elemental concentrations between sperm and seminal plasma and that higher sperm copper, sulfur and calcium are quantitatively associated with poorer semen quality and increased frequencies of genomic sperm defects. PMID:23042799

Schmid, Thomas E.; Grant, Patrick G.; Marchetti, Francesco; Weldon, Rosana H.; Eskenazi, Brenda; Wyrobek, Andrew J.

2013-01-01

157

Assay of sperm motility to study the effects of metal ions  

SciTech Connect

A method for quantitating sperm motility is applied here to study the effects of metal ions on animal cells. The quantitative technique is based on orienting sperm by subjecting them to flow and then measuring their capacity for returning to randomness when the orienting force is discontinued. The optical anisotropy of sperm permits determination of orientation with a spectrophotometer equipped with a flow cell. A wide range of concentrations of zinc, copper, and nickel ions were tested to determine their effects on the motility of sea-urchin sperm. Sea urchins are a ready and convenient source of sperm. Since energy production in sperm depends on their limited supply of endogenous substrate, this test system gives us a simple screening procedure for comparing the effects of various agents on the cell's capacity for utilizing energy. Nickel at concentrations higher than 10..pi../sup 5/M had an initial depressing effect on motility; however, this effect was eventually overcome, and in some cases overcompensation resulted in an increase motility. Zinc had either an enhancing or a depressing effect, depending not only on its concentration but on the time of exposure. At 10/sup -5/M it enhanced motility if present at the time the sperm were first shed in seawater, the time of high respiration. At 10..pi../sup 4/M it depressed motility only if present during the period of decreasing respiration, 1 to 2 hr after being shed into seawater. Copper depressed activity at 10..pi../sup 4/M to 10..pi../sup 6/M at all times tested.

Timourian, H.; Watchmaker, G.

1984-01-01

158

Sperm quantity and quality effects on fertilization success in a highly promiscuous passerine, the tree swallow Tachycineta bicolor  

Microsoft Academic Search

Sperm competition is widespread among animal taxa and considered a major force in sperm evolution. Recent comparative studies\\u000a have indicated that sperm competition selects for high sperm production capacity and long and fast-swimming spermatozoa across\\u000a species. Here, we examine the role of sperm quantity and quality for fertilization success of individual males in a Canadian\\u000a population of tree swallows Tachycineta

Terje Laskemoen; Oddmund Kleven; Frode Fossøy; Raleigh J. Robertson; Geir Rudolfsen; Jan T. Lifjeld

2010-01-01

159

Phospholipid composition of human sperm and seminal plasma in relation to sperm fertility.  

PubMed

The phospholipid and fatty acid composition of sperm was studied in 8 healthy and 16 infertile men. Infertile men randomly formed from the patients with normal semen parameters according to WHO criterion. Therefore, all semen parameters of infertile patients were similar to the same characteristics of the semen of healthy men, except the abnormal forms. The amount of abnormal forms in infertile men was significantly higher than in healthy men. Sperm from infertile men show a drastic loss of phosphatidyl ethanolamine. At the same time, the significant increase of phosphatidyl serine in the sperm and seminal plasma of sterile patients was found. Lysophosphatidyl serine in the sperm of the infertile men was detected. Fatty acid composition of the semen of infertile men was altered. The levels of stearic and n-3 polyunsaturated fatty acids (eicosopentaenoic and docosahexaenoic acids) was dramatically lowered, but the values of some n-6 polyunsaturated fatty acids (linolenic and docosatetraenoic) acids increased. There was significant positive correlation between docosahexaenoic acid and sperm motility (r = .82, p < .001) and negative correlation between linolenic acid and spermatozoa motility (r = -0.58. p < .05). Infertility of men with normal semen quality can originate from the disorder of sperm lipid metabolism. The drastic loss of phosphatidyl ethanolamine and n-3 polyunsaturated fatty acids with simultaneous enhancement of phosphatidyl serine and some n-6 polyunsaturated fatty acids in sperm could be an important cause of male infertility. PMID:11339641

Gulaya, N M; Margitich, V M; Govseeva, N M; Klimashevsky, V M; Gorpynchenko, I I; Boyko, M I

2001-01-01

160

Sexual Selection IV: Sperm Competition  

E-print Network

Sexual Selection IV: Sperm Competition BIO3176 - University of Ottawa Prof. Gabriel Blouin and extra-pair paternity are common, even in socially monogamous species Sperm Competition 2 Proof of Sperm Competition Harcourt et al 1981 Nature 293: 55-57 3 · Primates · Selection on ejaculate volume Proof of Sperm

Blouin-Demers, Gabriel

161

STABLE VARIANTS OF SPERM ANEUPLOIDY AMONG HEALTHY MEN SHOW ASSOCIATIONS BETWEEN GERMINAL AND SOMATIC ANEUPLOIDY  

EPA Science Inventory

Stable variants of sperm aneuploidy among healthy men show associations between germinal and somatic aneuploidy The purpose of this study was to identify healthy men who reproducibly produced increased frequencies of sperm with numerical chromosomal abnormalities and to d...

162

Sperm competition in bats.  

PubMed Central

Sperm competition is a widespread phenomenon influencing the evolution of male anatomy, physiology and behaviour. Bats are an ideal group for studying sperm competition. Females store fertile sperm for up to 200 days and the size of social groups varies from single animals to groups of hundreds of thousands. This study examines the relationship between social group size and investment in spermatogenesis across 31 species of microchiropteran bat using new and published data on testis mass and sperm length. In addition to male competition, I examined the effects of female reproductive biology on characteristics of spermatogenesis. Comparative studies indicate that relative testis mass is positively related to sperm competition risk in a wide range of taxa. Social group size may also influence the level of sperm competition, and one of the costs of living in groups may be decreased confidence of paternity. I used comparative analysis of independent contrast (CAIC) to control for phylogeny. Using two possible phylogenies and two measures of social group size, I found a significant positive relationship between social group size and testis mass. There was no relationship between testis mass and the dimension of the female reproductive tract or oestrus duration. Sperm length was not significantly related to body mass or group size, nor was it related to oestrus duration. PMID:9107054

Hosken, D J

1997-01-01

163

Membrane hyperpolarization during human sperm capacitation.  

PubMed

Sperm capacitation is a complex and indispensable physiological process that spermatozoa must undergo in order to acquire fertilization capability. Spermatozoa from several mammalian species, including mice, exhibit a capacitation-associated plasma membrane hyperpolarization, which is necessary for the acrosome reaction to occur. Despite its importance, this hyperpolarization event has not been adequately examined in human sperm. In this report we used flow cytometry to show that a subpopulation of human sperm indeed undergo a plasma membrane hyperpolarization upon in vitro capacitation. This hyperpolarization correlated with two other well-characterized capacitation parameters, namely an increase in intracellular pH and Ca(2+) concentration, measured also by flow cytometry. We found that sperm membrane hyperpolarization was completely abolished in the presence of a high external K(+) concentration (60 mM), indicating the participation of K(+) channels. In order to identify, which of the potential K(+) channels were involved in this hyperpolarization, we used different K(+) channel inhibitors including charybdotoxin, slotoxin and iberiotoxin (which target Slo1) and clofilium (a more specific blocker for Slo3). All these K(+) channel antagonists inhibited membrane hyperpolarization to a similar extent, suggesting that both members of the Slo family may potentially participate. Two very recent papers recorded K(+) currents in human sperm electrophysiologically, with some contradictory results. In the present work, we show through immunoblotting that Slo3 channels are present in the human sperm membrane. In addition, we found that human Slo3 channels expressed in CHO cells were sensitive to clofilium (50 ?M). Considered altogether, our data indicate that Slo1 and Slo3 could share the preponderant role in the capacitation-associated hyperpolarization of human sperm in contrast to what has been previously reported for mouse sperm, where Slo3 channels are the main contributors to the hyperpolarization event. PMID:24737063

López-González, I; Torres-Rodríguez, P; Sánchez-Carranza, O; Solís-López, A; Santi, C M; Darszon, A; Treviño, C L

2014-07-01

164

Increased monocyte TNF-alpha message stability contributes to trauma patients' increased TNF production.  

PubMed

Post-trauma elevation of tumor necrosis factor alpha (TNF-alpha) appears to be critical in mediating many symptoms of systemic inflammatory response syndrome (SIRS), resulting in late mortality. Although increased monocyte (mphi) TNF-alpha production plays a pivotal role in this TNF-alpha elevation, the molecular mechanisms leading to increased mphi TNF-alpha production have yet to be elucidated. We demonstrate that, although TNF-alpha mRNA levels are increased in all trauma patients' mphi, which produce elevated levels of TNF-alpha protein, in the majority of patients, these increased TNF-alpha mRNA levels are under normal transcriptional and posttranscriptional control. Consequently, the increased TNF-alpha production by these patients' mphi is probably due to preactivation of these mphi by trauma-released mediators. However, a small minority of patients, whose mortality rate was 57%, produce TNF-alpha of primarily the membrane-associated type. The mphi TNF-alpha mRNA accumulation of these patients in response to in vitro stimulation is significantly augmented. All of these patients experienced SIRS. In this subset of patients' mphi, TNF-alpha mRNA stability was aberrantly increased. Such an increase in TNF-alpha mRNA stability could lead to devastatingly prolonged production of TNF-alpha protein. This demonstration of increased TNF-alpha mRNA stability in post-trauma mphi represents a novel correlation of elevated membrane-associated TNF-alpha protein, increased mortality, and a mechanism for this occurrence. PMID:9335324

Furse, R K; Kodys, K; Zhu, D; Miller-Graziano, C L

1997-10-01

165

Cholesterol addition protects membrane intactness during cryopreservation of stallion sperm.  

PubMed

Addition of cholesterol to sperm membranes improved equine sperm stability during semen cryopreservation; however, it also reduced in vivo fertility. The objective of the present study was to determine the effects of adding cholesterol to stallion sperm prior to freezing, and subsequently removing it from frozen-thawed sperm. Semen from 12 stallions was subjected to four treatments: (T1) control, semen was diluted with Kenney extender, centrifuged, and resuspended to 100 x 10(6)spermatozoa/mL in INRA 82 freezing extender, packaged into 0.5-mL straws, cooled to 5 degrees C, and cryopreserved in liquid nitrogen; (T2) T1 with the addition of cholesterol before cooling (the cholesterol was incorporated to the sperm membranes with the methyl-beta-cyclodextrin-cholesterol complex); (T3) T2 with post-thaw removal of the cholesterol with 0.052 mg methyl-beta-cyclodextrin/50 x 10(6) sperm; and (T4) T3 with 0.156 mg methyl-beta-cyclodextrin/50 x 10(6) sperm. Sperm progressive motility and functional integrity of sperm plasma membranes were evaluated microscopically and by the hyposmotic swelling test, respectively. Using flow cytometry, physical integrity of sperm plasma membranes was assessed with propidium iodide, acrosomal integrity with fluoresceinated lectin peanut agglutinin, and rate of sperm acrosome reaction induced with of the calcium ionophore A23187. Cholesterol inclusion (T2) increased the proportion of frozen-thawed sperm with intact plasma membrane. Nevertheless, sperm from T2 (9.3+/-5.9%) had a lower rate of acrosome reaction after induction, compared to the control group (16.5+/-11.0%). After cholesterol removal, there was no increase in the induced acrosome reaction rate (T3: 11.3+/-7.1% and T4: 11.8+/-9.9%). Perhaps the cyclodextrin concentrations used were too low to remove sufficient cholesterol from sperm membranes to restore the ability of cryopreserved sperm to undergo an acrosome reaction. Regardless, the addition of cholesterol to improve post-thaw sperm integrity, and its subsequent removal, still has potential for cryopreservation of stallion sperm. PMID:19758774

Oliveira, C H; Vasconcelos, A B; Souza, F A; Martins-Filho, O A; Silva, M X; Varago, F C; Lagares, M A

2010-04-01

166

Aquaculture for increased fish production in East Africa ?  

E-print Network

Fish is produced for human consumption and other purposes through capture fisheries and aquaculture. Fish production from natural stocks has already reached its limits and is declining while aquaculture production is increasing. Aquaculture is making a significant contribution to fish production in several countries thus proving to be a potential alternative to supplement the declining capture fisheries. In East Africa the contribution of aquaculture to the total fish production is still insignificant although it has been practised in the region since the 1900s. The predominant aquaculture production system in East Africa at present is small scale earthen ponds characterised by low inputs and low yields. Important ingredients for the emergence of a commercial aquaculture industry are highlighted with emphasis on the need for a conducive and harmonised policy framework across the region. This paper advocates a focused plan of action for aquaculture development in the region and makes succinct recommendations for fast transformation of the industry.

J. Rutaisire; H. Charo-karisa; A. P. Shoko; B. Nyandat

167

Impact of adrenalectomy and dexamethasone treatment on testicular morphology and sperm parameters in rats: insights into the adrenal control of male reproduction.  

PubMed

Here we investigated the hypothesis that normal levels of glucocorticoids, a class of adrenal steroid hormones, are required for normal testicular and epididymal functions. We examined the effects of the manipulation of glucocorticoid plasma levels by bilateral adrenalectomy (1, 2, 7 and 15 days) alone or in combination with daily treatment with the synthetic glucocorticoid dexamethasone (DEX; 5 ?g/kg, i.p., 6 days) on the morphology of the testis and sperm parameters in rats. We showed that adrenalectomy led to a reduction in testicular sperm count and daily sperm production starting 2 days after surgery and a differential decrease in sperm count in the epididymis, according to the region and time post-adrenalectomy analysed. In parallel, testes from 7-day adrenalectomized (ADX) rats displayed a higher frequency of damaged seminiferous tubules and the presence of elongated spermatids retained in the basal epithelial compartment in stages IX-XVII, which is indicative of defective spermiation. The alkaline comet assay revealed a late effect of adrenalectomy on epididymal sperm DNA fragmentation, which was increased only 15 days after surgery. DEX treatment prevented the changes in testicular and epididymal sperm count observed in 7-day ADX rats, but failed to protect the testis from ADX-induced morphological abnormalities. Thus, our results indicated that glucocorticoids may be involved in events related to the maintenance of spermatogenesis and sperm maturation during adulthood. These findings provide new insights into the importance of adrenal steroids to male fertility. PMID:24925687

Silva, E J R; Vendramini, V; Restelli, A; Bertolla, R P; Kempinas, W G; Avellar, M C W

2014-11-01

168

Effect of Phaleria macrocarpa on Sperm Characteristics in Adult Rats  

PubMed Central

Purpose: The purpose of this study was to determine the effects of Phaleria macrocarpa (PM) on male fertility by assessing its effect on the sperm characteristics which included the sperm count, motility, viability and morphology. Methods: Eighteen male rats were equally divided into three groups. Each group of rats was orally supplemented for 7 weeks either with PM aqueous extract (240 mg/kg), distilled water (0 mg/kg) or testosterone hormone, Andriol® Testocaps™ (4 mg/kg) respectively. On the last day of supplementation period, the rats were sacrificed and sperm was obtained from cauda epididymis via orchidectomy. The sperm count, motility, viability and morphology were determined. Results: PM aqueous extract significantly increased (p<0.05) the percentage of sperm viability. However, there was no significant effect of PM on the percentage of both sperm motility and morphology. The mean of body weight declined significantly in rats supplemented with PM aqueous extract compared to control groups (p<0.05). Conclusion: The results showed that PM significantly increased sperm viability without changing the sperm motility and morphology. Hence, this study suggests that PM offers an alternative way to improve male fertility by improving the sperm quality. PMID:24312859

Parhizkar, Saadat; Yusoff, Maryam Jamielah; Dollah, Mohammad Aziz

2013-01-01

169

The sexually selected sperm hypothesis, maternal effects, and sperm competitive success  

E-print Network

The sexually selected sperm hypothesis, maternal effects, and sperm competitive success in the bulb of Lausanne, Lausanne, Switzerland ABSTRACT Background: The sexually selected sperm hypothesis predicts this result. Keywords: bulb mite, maternal effects, polyandry, sexually selected sperm hypothesis, sperm

Alvarez, Nadir

170

Human Sperm Tail Proteome Suggests New Endogenous Metabolic Pathways*  

PubMed Central

Proteomic studies are contributing greatly to our understanding of the sperm cell, and more detailed descriptions are expected to clarify additional cellular and molecular sperm attributes. The aim of this study was to characterize the subcellular proteome of the human sperm tail and, hopefully, identify less concentrated proteins (not found in whole cell proteome studies). Specifically, we were interested in characterizing the sperm metabolic proteome and gaining new insights into the sperm metabolism issue. Sperm were isolated from normozoospermic semen samples and depleted of any contaminating leukocytes. Tail fractions were obtained by means of sonication followed by sucrose-gradient ultracentrifugation, and their purity was confirmed via various techniques. Liquid chromatography and tandem mass spectrometry of isolated sperm tail peptides resulted in the identification of 1049 proteins, more than half of which had not been previously described in human sperm. The categorization of proteins according to their function revealed two main groups: proteins related to metabolism and energy production (26%), and proteins related to sperm tail structure and motility (11%). Interestingly, a great proportion of the metabolic proteome (24%) comprised enzymes involved in lipid metabolism, including enzymes for mitochondrial beta-oxidation. Unexpectedly, we also identified various peroxisomal proteins, some of which are known to be involved in the oxidation of very long chain fatty acids. Analysis of our data using Reactome suggests that both mitochondrial and peroxisomal pathways might indeed be active in sperm, and that the use of fatty acids as fuel might be more preponderant than previously thought. In addition, incubation of sperm with the fatty acid oxidation inhibitor etomoxir resulted in a significant decrease in sperm motility. Contradicting a common concept in the literature, we suggest that the male gamete might have the capacity to obtain energy from endogenous pools, and thus to adapt to putative exogenous fluctuations. PMID:23161514

Amaral, Alexandra; Castillo, Judit; Estanyol, Josep Maria; Ballescà, José Luís; Ramalho-Santos, João; Oliva, Rafael

2013-01-01

171

Effect of oxamic analogues on functional mice sperm parameters.  

PubMed

The present study evaluates the effect of oxamate derivatives (N-ethyl, N-propyl, N-butyl oxamates) on functional murine sperm parameters, towards a new male non-hormonal contraceptive. These derivatives are selective inhibitors of lactate dehydrogenase-C4 (LDH-C4). LDH-C4 is a sperm-specific enzyme that plays an important role in ATP production for maintaining progressive motility as well as to induce capacitation and hyperactivation. The results demonstrate that all oxamate derivatives selectively inhibited LDH-C4 in mouse sperm extracts. The IC(50) values for hexokinase and glyceraldehyde-3-phosphate dehydrogenase were at least an order of magnitude greater than LDH-C4 IC(50) values. Prodrugs of oxamate derivatives assayed on sperm cells diminished normal sperm motility parameters, acrosome reaction, and cell viability in a concentration dependent manner. Also, we performed in vivo studies to determine the potential toxicity and possible contraceptive ability of these inhibitors. Mouse sperm were more sensitive to the N-butyl oxamate ethyl ester (NBOXet). Furthermore, results showed that NBOXet was of a low toxicity substance that diminished the total and progressive motility as well as the kinematic parameters of sperm cells. Data from in vitro and in vivo studies showed that N-butyl oxamate and its prodrug, are selective inhibitors of sperm LDH-C4, has low toxicity, and inhibits sperm progressive motility, offering some of the desirable characteristics of a male contraceptive: effect, low toxicity, and selectivity. PMID:24654556

Cordero-Martínez, Joaquín; Aguirre-Alvarado, Charmina; Wong, Carlos; Rodríguez-Páez, Lorena

2014-08-01

172

Immobilization of sperm by condoms and their components.  

PubMed

Condoms and other rubber products immobilize sperm, but the mechanism is unknown. Sperm motility and eosin Y exclusion were measured following exposure of samples of semen to latex condoms of various types. Sperm motility was markedly reduced by exposure to all latex condoms, but eosin Y exclusion was unchanged. While there appeared to be some variability between semen samples and in time to complete immobilization of all sperm, condoms from one batch were similar. The immobilizing effect was not altered by prewashing the condom with buffer, chelating agent or acid. After immobilization, motility was not recovered by sperm washed in buffer, mixed with normal mid-cycle cervical mucus, or exposed to caffeine or adenosine triphosphate after demembranation with detergent. Studies with components of condoms indicated that raw latex and zinc dimethyl- and dibutyl-dithiocarbamate accelerators immobilized sperm within 30 min. In contrast, silicone rubber had no effect on sperm motility for up to 4 h. Enhancement of the sperm immobilizing effect might improve the contraceptive efficacy of condoms, while a useful non-toxic sperm collecting device for semen analysis, artificial insemination or in vitro fertilisation might be developed by omitting the toxic components from the rubber. PMID:2439182

Jones, D M; Kovacs, G T; Harrison, L; Jennings, M G; Baker, H W

1986-12-01

173

Influence of bovine sperm DNA fragmentation and oxidative stress on early embryo in vitro development outcome.  

PubMed

Sperm chromatin fragmentation may be caused by a number of factors, the most significant of which is reactive oxygen species. However, little is known about the effect of sperm oxidative stress (OS) on DNA integrity, fertilization, and embryonic development in cattle. Therefore, the goal of this study was to evaluate the influence of sperm OS susceptibility on the DNA fragmentation rate and in vitro embryo production (IVP) in a population of bulls. Groups of cryopreserved sperm samples were divided into four groups, based on their susceptibility to OS (G1, low OS; G2, average OS; G3, high OS; and G4, highest OS). Our results demonstrated that the sperm DNA integrity was compromised in response to increased OS susceptibility. Furthermore, semen samples with lower susceptibility to OS were also less susceptible to DNA damage (G1, 4.06%; G2, 6.09%; G3, 6.19%; and G4, 6.20%). In addition, embryo IVP provided evidence that the embryo cleavage rate decreased as the OS increased (G1, 70.18%; G2, 62.24%; G3, 55.85%; and G4, 50.93%), but no significant difference in the blastocyst rate or the number of blastomeres was observed among the groups. The groups with greater sensitivity to OS were also associated with a greater percentage of apoptotic cells (G1, 2.6%; G2, 2.76%; G3, 5.59%; and G4, 4.49%). In conclusion, we demonstrated that an increased susceptibility to OS compromises sperm DNA integrity and consequently reduces embryo quality. PMID:23940385

Simões, Renata; Feitosa, Weber Beringui; Siqueira, Adriano Felipe Perez; Nichi, Marcilio; Paula-Lopes, Fabíola Freitas; Marques, Mariana Groke; Peres, Maria Angélica; Barnabe, Valquíria Hyppolito; Visintin, José Antônio; Assumpção, Mayra Elena Ortiz

2013-01-01

174

Sperm Quality Control  

NSDL National Science Digital Library

New research from the University of Missouri-Columbia suggests how defective sperm are tagged for destruction. This 57 second audio recording from Science Update originally aired on Monday, February 11, 2008.

Science Update (AAAS; )

2008-05-06

175

Intracytoplasmic Sperm Injection (ICSI)  

MedlinePLUS

... fertilization occurs, the fertilized egg (now called an embryo) grows in a laboratory for 1 to 5 ... damaged. • The egg might not grow into an embryo even after it is injected with sperm. • The ...

176

Engineering the lactococcal mevalonate pathway for increased sesquiterpene production.  

PubMed

Isoprenoids are a large, diverse group of secondary metabolites which has recently raised a renewed research interest due to genetic engineering advances, allowing specific isoprenoids to be produced and characterized in heterologous hosts. Many researches on metabolic engineering of heterologous hosts for increased isoprenoid production are focussed on Escherichia coli and yeasts. E. coli, as most prokaryotes, use the 2-C-methyl-d-erythritol-4-phosphate (MEP) pathway for isoprenoid production. Yeasts on the other hand, use the mevalonate pathway which is commonly found in eukaryotes. However, Lactococcus lactis is an attractive alternative host for heterologous isoprenoid production. Apart from being food-grade, this Gram-positive prokaryote uses the mevalonate pathway for isoprenoid production instead of the MEP pathway. Previous studies have shown that L. lactis is able to produce sesquiterpenes through heterologous expression of plant sesquiterpene synthases. In this work, we analysed the gene expression of the lactococcal mevalonate pathway through RT-qPCR to successfully engineer L. lactis as an efficient host for isoprenoid production. We then overexpressed the mvk gene singly or co-expressed with the mvaA gene as an attempt to increase ?-sesquiphellandrene production in L. lactis. It was observed that co-expression of mvk with mvaA doubled the amount of ?-sesquiphellandrene produced. PMID:24828482

Song, Adelene A; Abdullah, Janna Ong; Abdullah, Mohd P; Shafee, Norazizah; Othman, Roohaida; Noor, Normah Mohd; Rahim, Raha A

2014-06-01

177

Exposure to endosulfan influences sperm competition in Drosophila melanogaster.  

PubMed

Dwindling male fertility due to xenobiotics is of global concern. Accordingly, male reproductive toxicity assessment of xenobiotics through semen quality analysis in exposed males, and examining progeny production of their mates is critical. These assays, in part, are biased towards monogamy. Females soliciting multiple male partners (polyandry) is the norm in many species. Polyandry incites sperm competition and allows females to bias sperm use. However, consequences of xenobiotic exposure to the sperm in the light of sperm competition remain to be understood. Therefore, we exposed Drosophila melanogaster males to endosulfan, and evaluated their progeny production as well as the ability of their sperm to counter rival control sperm in the storage organs of females sequentially mated to control/exposed males. Endosulfan (2??g/ml) had no significant effect on progeny production and on the expression of certain genes associated with reproduction. However, exposed males performed worse in sperm competition, both as 1(st) and 2(nd) male competitors. These findings indicate that simple non-competitive measures of reproductive ability may fail to demonstrate the harmful effects of low-level exposure to xenobiotics on reproduction and advocate consideration of sperm competition, as a parameter, in the reproductive toxicity assessment of xenobiotics to mimic situations prevailing in the nature. PMID:25503806

Misra, Snigdha; Kumar, Ajay; Ratnasekhar, Ch; Sharma, Vandana; Mudiam, Mohana Krishna Reddy; Ram, Kristipati Ravi

2014-01-01

178

Increasing Loyalty to Breastfeeding: Investigating a Product Development Strategy  

Microsoft Academic Search

This article demonstrates how social marketing insights were used to influence women's loyalty to breastfeeding. The article reports on a social marketing campaign undertaken by the Australian Breastfeeding Association and a government health department, which used a product development strategy in order to increase breastfeeding loyalty. Seeking new approaches to support breastfeeding behaviors is critical and timely, because while initiation

Joy Parkinson; Rebekah Russell-Bennett; Josephine Previte

2012-01-01

179

Breeding Technologies to Increase Crop Production in a Changing World  

NSDL National Science Digital Library

To feed the several billion people living on this planet, the production of high-quality food must increase with reduced inputs, but this accomplishment will be particularly challenging in the face of global environmental change. Crop improvement through breeding brings immense value relative to investment and offers an effective approach to improving food security.

Mark Tester (University of Adelaide; )

2010-02-12

180

Oxidative phosphorylation is essential for felid sperm function, but is substantially lower in cheetah (Acinonyx jubatus) compared to domestic cat (Felis catus) ejaculate.  

PubMed

Compared with the normospermic domestic cat, sperm metabolic function is compromised in the teratospermic cat and cheetah, but the pathway(s) involved in this deficiency are unknown. Glycolysis is essential for sperm motility, yet it appears to function normally in spermatozoa of either species regardless of structural morphology. We conducted a comparative study to further understand the mechanisms of energy production in felid spermatozoa, with the hypothesis that oxidative phosphorylation is required for normal sperm function and is impaired in teratospermic ejaculates. Electroejaculates from both species were stained with MitoTracker to quantify mitochondrial membrane potential (MMP) or were incubated to assess changes in sperm function (motility, acrosomal integrity, and lactate production) after mitochondrial inhibition with myxothiazol. Sperm midpiece dimensions also were quantified. Sperm mitochondrial fluorescence (directly proportional to MMP) was ~95% lower in the cheetah compared with the normospermic and teratospermic cat, despite the cheetah having a 10% longer midpiece. In both species, MMP was increased 5-fold in spermatozoa with retained cytoplasm compared with structurally normal cells. Inhibition of oxidative phosphorylation impaired sperm function in both species, but a 100-fold higher inhibitor concentration was required in the cat compared with the cheetah. Collectively, findings revealed that oxidative phosphorylation was required for sperm function in the domestic cat and cheetah. This pathway of energy production appeared markedly less active in the cheetah, indicating a species-specific vulnerability to mitochondrial dysfunction. The unexpected, cross-species linkage between retained cytoplasmic droplets and elevated MMP may reflect increased concentrations of metabolic enzymes or substrates in these structures. PMID:21593479

Terrell, Kimberly A; Wildt, David E; Anthony, Nicola M; Bavister, Barry D; Leibo, S P; Penfold, Linda M; Marker, Laurie L; Crosier, Adrienne E

2011-09-01

181

Female promiscuity promotes the evolution of faster sperm in cichlid fishes.  

PubMed

Sperm competition, the contest among ejaculates from rival males to fertilize ova of a female, is a common and powerful evolutionary force influencing ejaculate traits. During competitive interactions between ejaculates, longer and faster spermatozoa are expected to have an edge; however, to date, there has been mixed support for this key prediction from sperm competition theory. Here, we use the spectacular radiation of cichlid fishes from Lake Tanganyika to examine sperm characteristics in 29 closely related species. We provide phylogenetically robust evidence that species experiencing greater levels of sperm competition have faster-swimming sperm. We also show that sperm competition selects for increases in the number, size, and longevity of spermatozoa in the ejaculate of a male, and, contrary to expectations from theory, we find no evidence of trade-offs among sperm traits in an interspecific analysis. Also, sperm swimming speed is positively correlated with sperm length among, but not within, species. These different responses to sperm competition at intra- and interspecific levels provide a simple, powerful explanation for equivocal results from previous studies. Using phylogenetic analyses, we also reconstructed the probable evolutionary route of trait evolution in this taxon, and show that, in response to increases in the magnitude of sperm competition, the evolution of sperm traits in this clade began with the evolution of faster (thus, more competitive) sperm. PMID:19164576

Fitzpatrick, John L; Montgomerie, Robert; Desjardins, Julie K; Stiver, Kelly A; Kolm, Niclas; Balshine, Sigal

2009-01-27

182

Centrifugation on Percoll density gradient enhances motility, membrane integrity and in vitro fertilizing ability of frozen-thawed boar sperm.  

PubMed

Summary The effects of Percoll density gradient centrifugation on sperm quality, in vitro fertilizability and developmental capacity of frozen-thawed boar sperm were evaluated. Two-step density gradient centrifugation by Percoll enhanced significantly the motility parameters of sperm compared with a simple centrifugation procedure. Percentages of motile sperm and sperm with intact plasma and acrosome membranes after Percoll separation were significantly greater than those after simple centrifugation. The rates of penetration, cleavage and blastocyst formation after in vitro fertilization were significantly improved by Percoll separation compared with simple centrifugation and were influenced positively by the intactness of sperm head membranes, but not any sperm motility parameters. However, insemination with increased concentrations of sperm prepared by Percoll gradient centrifugation did not improve the success of fertilization and embryo development in vitro. Our results indicate that the integrity of sperm head membranes after Percoll separation is important for successful embryo development in vitro, more so than sperm motility. PMID:23659202

Noguchi, Michiko; Yoshioka, Koji; Hikono, Hirokazu; Iwagami, Gentaro; Suzuki, Chie; Kikuchi, Kazuhiro

2015-02-01

183

A cAMP Regulated K +Selective Channel from the Sea Urchin Sperm Plasma Membrane  

Microsoft Academic Search

Ion channels are deeply involved in sperm physiology. In sea urchin sperm cyclic nucleotide levels increase during quimotaxis and in the acrosome reaction (AR). Although cyclic nucleotides are second messengers known to directly or indirectly modulate ion channels, it is not clear how they modulate sperm responses to the egg outer layer. Here, we describe a cAMP regulated K+-selective channel

Pedro Labarca; Celia Santi; Otilia Zapata; Ezequiel Morales; Carmen Beltrán; Arturo Liévano; Alberto Darszon

1996-01-01

184

An automatic system to study sperm motility and energetics  

PubMed Central

An integrated robotic laser and microscope system has been developed to automatically analyze individual sperm motility and energetics. The custom-designed optical system directs near-infrared laser light into an inverted microscope to create a single-point 3-D gradient laser trap at the focal spot of the microscope objective. A two-level computer structure is described that quantifies the sperm motility (in terms of swimming speed and swimming force) and energetics (measuring mid-piece membrane potential) using real-time tracking (done by the upper-level system) and fluorescent ratio imaging (done by the lower-level system). The communication between these two systems is achieved by a gigabit network. The custom-built image processing algorithm identifies the sperm swimming trajectory in real-time using phase contrast images, and then subsequently traps the sperm by automatically moving the microscope stage to relocate the sperm to the laser trap focal plane. Once the sperm is stably trapped (determined by the algorithm), the algorithm can also gradually reduce the laser power by rotating the polarizer in the laser path to measure the trapping power at which the sperm is capable of escaping the trap. To monitor the membrane potential of the mitochondria located in a sperm’s mid-piece, the sperm is treated with a ratiometrically-encoded fluorescent probe. The proposed algorithm can relocate the sperm to the center of the ratio imaging camera and the average ratio value can be measured in real-time. The three parameters, sperm escape power, sperm swimming speed and ratio values of the mid-piece membrane potential of individual sperm can be compared with respect to time. This two-level automatic system to study individual sperm motility and energetics has not only increased experimental throughput by an order of magnitude but also has allowed us to monitor sperm energetics prior to and after exposure to the laser trap. This system should have application in both the human fertility clinic and in animal husbandry. PMID:18299996

Nascimento, Jaclyn M.; Chandsawangbhuwana, Charlie; Botvinick, Elliot L.; Berns, Michael W.

2012-01-01

185

An investigation of productivity increases from hydraulic fracturing treatments  

E-print Network

AN INVESTIGATION OF PRODUCTIVITY INCREASES FROM HYDRAULIC FRACTURING TREATMENTS A Thesis b7 Robert Joe Boriskie Submitted to the Graduate School of the Agricultural and Mechanical College of Texas in partial fulfillment of the requirements... Head of Department) August, 1963 1. ABSTRACT 2. INTRODUCTION. TABLE OF CONTENTS PRgB 3. THEORY AND PROCEDURE. 4. DISCUSSION OF RESULTS. . 5. CONCLUSIONS. 6. ACKNOWLEDGEMENT. 7. APPENDIX. 8. REFERENCES. 18 19 20 32 LIST OF FIGURES...

Boriskie, Robert Joe

2012-06-07

186

Increase Productivity - Implement Energy Management Systems with Project Management Techniques  

E-print Network

INCREASE PRODUCTIVITY IMPLEMENT ENERGY MANAGEMENT SYSTEMS WITH PROJECT MANAGEMENT TECHNIQUES M. Pete Spinner, P.E. Glass Division, Ford Motor Company Detroit, Michigan Lawrence Institute of Technology Southfield, Michigan ABSTRACT... major work items that have to be done to prepare have climbed appreciably (from $0.50 to $1 per the feasibility report. million BTU in 1978 to $4 and $5 in 1982) there has been an abrupt halt in 1983 to escalating This presentation highlights the work...

Spinner, M. P.

1984-01-01

187

The dynamics of sperm cooperation in a competitive environment  

E-print Network

Sperm cooperation has evolved in a variety of taxa and is often considered a response to sperm competition, yet the benefit of this form of collective movement remains unclear. Here we use fine-scale imaging and a minimal mathematical model to study sperm aggregation in the rodent genus $Peromyscus$. We demonstrate that as the number of sperm cells in an aggregate increase, the group moves with more persistent linearity but without increasing speed; this benefit, however, is offset in larger aggregates as the geometry of the group forces sperm to swim against one another. The result is a non-monotonic relationship between aggregate size and average velocity with both a theoretically predicted and empirically observed optimum of 6-7 sperm/aggregate. To understand the role of sexual selection in driving these sperm group dynamics, we compared two sister-species with divergent mating systems and find that sperm of $P.\\,maniculatus$ (highly promiscuous), which have evolved under intense competition, form optimal-...

Fisher, H S; Hoekstra, H E; Mahadevan, L

2014-01-01

188

The healthy men study: an evaluation of exposure to disinfection by-products in tap water and sperm quality  

EPA Science Inventory

BACKGROUND: Chlorination of drinking water generates disinfection by-products (DBPs), which have been shown to disrupt spermatogenesis in rodents at high doses, suggesting that DBPs could pose a reproductive risk to men. In this study we assessed DBP exposure and testicular toxic...

189

Effect of heterologous and homologous seminal plasma on stallion sperm quality.  

PubMed

Removing most of the seminal plasma (SP) from stallion semen has been shown to improve survival during cooled storage, yet adding small quantities of SP may improve pregnancy rates or cryosurvival. Furthermore, there is considerable controversy about whether the stallion's own SP or heterologous SP produces the best effect, possibly because of the variation between stallions in SP proteins or because some homologous SP remained in the sperm preparation. The SP is removed completely from stallion spermatozoa prepared by colloid centrifugation. Thus, the aim of the present study was (1) to investigate the effect of adding back SP to colloid centrifuged spermatozoa to determine its effect on spermatozoa; and (2) to investigate whether the stallion's own SP had a greater or lesser effect than heterologous SP. Conventional semen doses were sent from a stud overnight to the laboratory using standard transport conditions. Once at the laboratory, the semen samples were used for single layer centrifugation with Androcoll-E, and the resulting sperm preparations were treated with heterologous SP. Adding SP had a small but significant effect on sperm motility but no effect on the proportion of spermatozoa that had acrosome reacted. There were significant increases in hydrogen peroxide production and chromatin damage (P < 0.001). When homologous and heterologous SP were compared, considerable variation was observed between stallions, so that it was not possible to predict whether homologous or heterologous SP, or no SP, will produce the best motility for spermatozoa from any given stallion. Therefore, it is necessary to test different combinations of spermatozoa and SP to find the optimal effect on motility. The SP from most stallions increased reactive oxygen species and chromatin damage. In conclusion, the interaction between SP and spermatozoa depends on the origin of both SP and spermatozoa. If it is desirable to add SP to stallion sperm samples, it should be done directly before insemination rather than before storage, because of increased hydrogen peroxide production and sperm chromatin damage. PMID:24768057

Morrell, J M; Georgakas, A; Lundeheim, N; Nash, D; Davies Morel, M C G; Johannisson, A

2014-07-01

190

The Sperm Whale Project  

NSDL National Science Digital Library

In 1988, the carcass of a sperm whale washed up on East Chugach Island in Alaska. To capitalize on this rare opportunity, the Pratt Museum created the Sperm Whale Project, designed to "promote ocean conservation through enhanced cross disciplinary marine science education" for residents and visitors to the Kachemak Bay area, where the museum is located. New to the Scout Report, the Sperm Whale Project Web site offers a fascinating look at the history of this project, from the discovery of the carcass to the preparation and articulation of its skeleton for display at the Pratt Museum, a process that enlisted the help of area high school students. Nicely presented and full of interesting photos, this Web site should be worth a visit from anyone interested in whales, skeletology, or museum science in general.

191

Biological sample preparation: attempts on productivity increasing in bioanalysis.  

PubMed

Sample preparation is an important step of any biomedical analysis. Development and validation of fast, reproducible and reliable sample preparation methods would be very helpful in increasing productivity. Except for a few direct injection methods, almost all biological samples should at least be diluted before any analysis. Sometimes dilution is not possible because of the low concentration of the target analyte in the sample, and alternative pretreatments, such as filtration, precipitation and sample clean up using different extraction methods, are needed. This review focuses on the recent achievements in the pretreatment of biological samples and investigates them in six categories (i.e., dilution, filtration/dialysis, precipitation, extraction [solid-phase extraction, liquid-liquid extraction], novel techniques [turbulent flow chromatography, immunoaffinity method, electromembrane extraction] and combined methods). Each category will be discussed according to its productivity rate and suitability for routine analysis, and the discussed methods will be compared according to the mentioned indices. PMID:25077628

Soltani, Somaieh; Jouyban, Abolghasem

2014-01-01

192

Ram seminal plasma proteins contribute to sperm capacitation and modulate sperm-zona pellucida interaction.  

PubMed

Incubation of ram spermatozoa in capacitating conditions with cAMP-elevating agents promotes a progressive time-dependent increase in the capacitated sperm subpopulation. In this study, the fertilizing capacity of ram spermatozoa (ability to bind to the zona pellucida, ZBA rate) capacitated in these conditions was determined. The results showed an increase (P < 0.001) in ZBA rate related to control samples in basal medium that contained BSA, calcium, and bicarbonate (1.97 ± 0.19 vs. 1.31 ± 0.09 sperm bound/oocyte, respectively). A significant correlation between protein tyrosine phosphorylation and ZBA rate (P < 0.05, r = 0.501) corroborated that incubation in a "high-cAMP" environment improves the fertilizing ability of ram spermatozoa. Likewise, the presence of two seminal plasma (SP) proteins able to protect sperm against cold shock (RSVP14 and RSVP20) was evidenced in both SP and the ram sperm surface, and their influence in the fertilizing ability of spermatozoa capacitated in basal medium or with cAMP-elevating agents was determined. The results verified that RSVP14 and RSVP20 act as decapacitating factors given that their addition to SP-free sperm samples previously to capacitation maintained high proportions of the noncapacitated sperm pattern with no increase in protein tyrosine phosphorylation. However, the obtained ZBA rate in the high-cAMP-containing samples was increased in the presence of RSVP20 (P < 0.05). These findings would indicate that the stimulating effect exerted by this protein on the sperm-oocyte binding occurs downstream from the cAMP generation and that the mechanisms by which RSVP20 promotes the zona pellucida binding might be independent of protein tyrosine phosphorylation. PMID:25515364

Luna, C; Colás, C; Casao, A; Serrano, E; Domingo, J; Pérez-Pé, R; Cebrián-Pérez, J A; Muiño-Blanco, T

2015-03-01

193

Sequential male mate choice under sperm competition risk  

PubMed Central

Male eagerness to mate is a central paradigm of sexual selection theory. However, limited sperm supplies mean that male sexual restraint might sometimes be favored under promiscuous mating. Here, we demonstrate dynamic plasticity in male mating effort when females are encountered sequentially under varying sperm competition risk. Rather than showing consistent eagerness to mate, male house mice (Mus musculus domesticus) instead tailor their mating effort according to likely reproductive payoffs. They are significantly less likely to mate when sperm competition is certain and potential reproductive payoffs low, but dramatically increase investment if they do choose to mate under such circumstances. By contrast, male mice are significantly more likely to mate in situations simulating extra-territorial copulations, where future risk of competition is high but so too are potential reproductive rewards. Differential mating propensity appears to be the primary mechanism by which male house mice allocate sperm adaptively under sperm competition risk because we find no evidence for facultative adjustment of sperm numbers per ejaculate or ejaculation frequency in response to female-related cues. We conclude that sequential male mate choice under sperm competition risk could be a widespread but often unappreciated mechanism of strategic sperm allocation. PMID:24822023

2014-01-01

194

Polyandry in the medfly - shifts in paternity mediated by sperm stratification and mixing  

PubMed Central

Background In the Mediterranean fruit fly (medfly), Ceratitis capitata, a highly invasive agricultural pest species, polyandry, associated with sperm precedence, is a recurrent behaviour in the wild. The absence of tools for the unambiguous discrimination between competing sperm from different males in the complex female reproductive tract has strongly limited the understanding of mechanisms controlling sperm dynamics and use. Results Here we use transgenic medfly lines expressing green or red fluorescent proteins in the spermatozoa, which can be easily observed and unambiguously differentiated within the female fertilization chamber. In twice-mated females, one day after the second mating, sperm from the first male appeared to be homogenously distributed all over the distal portion of each alveolus within the fertilization chamber, whereas sperm from the second male were clearly concentrated in the central portion of each alveolus. This distinct stratified sperm distribution was not maintained over time, as green and red sperm appeared homogeneously mixed seven days after the second mating. This dynamic sperm storage pattern is mirrored by the paternal contribution in the progeny of twice-mated females. Conclusions Polyandrous medfly females, unlike Drosophila, conserve sperm from two different mates to fertilize their eggs. From an evolutionary point of view, the storage of sperm in a stratified pattern by medfly females may initially favour the fresher ejaculate from the second male. However, as the second male's sperm gradually becomes depleted, the sperm from the first male becomes increasingly available for fertilization. The accumulation of sperm from different males will increase the overall genetic variability of the offspring and will ultimately affect the effective population size. From an applicative point of view, the dynamics of sperm storage and their temporal use by a polyandrous female may have an impact on the Sterile Insect Technique (SIT). Indeed, even if the female's last mate is sterile, an increasing proportion of sperm from a previous mating with a fertile male may contribute to sire viable progeny. PMID:25470981

2014-01-01

195

Long Polyglutamine Tracts in the Androgen Receptor Are Associated with Reduced TransActivation, Impaired Sperm Production, and Male Infertility  

Microsoft Academic Search

The X-linked androgen receptor (AR) gene contains two polymor- phic trinucleotide repeat segments that code for polyglutamine and polyglycine tracts in the N-terminal trans-activation domain of the AR protein. Changes in the lengths of these polymorphic repeat seg- ments have been associated with increased risk of prostate cancer, an androgen-dependent tumor. Expansion of the polyglutamine tract causes a rare neuromuscular

THEIN G. TUT; FARID J. GHADESSY; M. A. TRIFIRO; L. PINSKY; E. L. YONG

2010-01-01

196

Raman Spectroscopy of DNA Packaging in Individual Human Sperm Cells distinguishes Normal from Abnormal Cells  

SciTech Connect

Healthy human males produce sperm cells of which about 25-40% have abnormal head shapes. Increases in the percentage of sperm exhibiting aberrant sperm head morphologies have been correlated with male infertility, and biochemical studies of pooled sperm have suggested that sperm with abnormal shape may contain DNA that has not been properly repackaged by protamine during spermatid development. We have used micro-Raman spectroscopy to obtain Raman spectra from individual human sperm cells and examined how differences in the Raman spectra of sperm chromatin correlate with cell shape. We show that Raman spectra of individual sperm cells contain vibrational marker modes that can be used to assess the efficiency of DNA-packaging for each cell. Raman spectra obtained from sperm cells with normal shape provide evidence that DNA in these sperm is very efficiently packaged. We find, however, that the relative protein content per cell and DNA packaging efficiencies are distributed over a relatively wide range for sperm cells with both normal and abnormal shape. These findings indicate that single cell Raman spectroscopy should be a valuable tool in assessing the quality of sperm cells for in-vitro fertilization.

Huser, T; Orme, C; Hollars, C; Corzett, M; Balhorn, R

2009-03-09

197

Sperm motility activation in the euryhaline tilapia Sarotherodon melanotheron heudelotii (Dumeril, 1859) acclimatized to fresh, sea or hypersaline waters.  

E-print Network

analyzer. Motility was initiated by 1:100 sperm dilution in a drop of swimming medium on a microscope slide increased. Hence, sperm motility was enough (even though not maximal) to ensure egg fertilization at the #12

Villefranche sur mer

198

Sterols in spermatogenesis and sperm maturation  

PubMed Central

Mammalian spermatogenesis is a complex developmental program in which a diploid progenitor germ cell transforms into highly specialized spermatozoa. One intriguing aspect of sperm production is the dynamic change in membrane lipid composition that occurs throughout spermatogenesis. Cholesterol content, as well as its intermediates, differs vastly between the male reproductive system and nongonadal tissues. Accumulation of cholesterol precursors such as testis meiosis-activating sterol and desmosterol is observed in testes and spermatozoa from several mammalian species. Moreover, cholesterogenic genes, especially meiosis-activating sterol-producing enzyme cytochrome P450 lanosterol 14?-demethylase, display stage-specific expression patterns during spermatogenesis. Discrepancies in gene expression patterns suggest a complex temporal and cell-type specific regulation of sterol compounds during spermatogenesis, which also involves dynamic interactions between germ and Sertoli cells. The functional importance of sterol compounds in sperm production is further supported by the modulation of sterol composition in spermatozoal membranes during epididymal transit and in the female reproductive tract, which is a prerequisite for successful fertilization. However, the exact role of sterols in male reproduction is unknown. This review discusses sterol dynamics in sperm maturation and describes recent methodological advances that will help to illuminate the complexity of sperm formation and function. PMID:23093550

Keber, Rok; Rozman, Damjana; Horvat, Simon

2013-01-01

199

Sperm Whale (Physeter macrocephalus)  

E-print Network

species Listed as Endangered Under the U.S. Endangered Species Act of 1973. Marine Fisheries Review, 61 Act (ESA), the Endangered Species Conservation Act of 1969, and remained listed after the passage.3.2 Listing history Original Listing The sperm whale was listed under the precursor to the Endangered Species

200

Effect of various commercial buffers on sperm viability and capacitation.  

PubMed

A wide variety of sperm preparation protocols are currently available for assisted conception. They include density gradient separation and washing methods. Both aim at isolating and capacitating as much motile sperm as possible for subsequent oocyte fertilization. The aim of this study was to examine the effects of four commercial sperm washing buffers on sperm viability and capacitation. Semen samples from 48 healthy donors (normal values of sperm count, motility, morphology, and volume) were analyzed. After separation (density gradient 40/80%), sperm were incubated in various buffers then analysed for reactive oxygen species (ROS) production, viability, tyrosine phosphorylation (Tyr-P), cholera toxin B subunit (CTB) labeling, and the acrosome reaction (AR). The buffers affected ROS generation in various ways resulting either in rapid cell degeneration (when the amount of ROS was too high for cell survival) or the inability of the cells to maintain correct functioning (when ROS were too few). Only when the correct ROS generation curve was maintained, suitable membrane reorganization, evidenced by CTB labeling was achieved, leading to the highest percentages of both Tyr-P- and acrosome-reacted-cells. Distinguishing each particular pathological state of the sperm sample would be helpful to select the preferred buffer treatment since both ROS production and membrane reorganization can be significantly altered by commercial buffers. PMID:24673547

Andrisani, Alessandra; Donà, Gabriella; Ambrosini, Guido; Bonanni, Guglielmo; Bragadin, Marcantonio; Cosmi, Erich; Clari, Giulio; Armanini, Decio; Bordin, Luciana

2014-08-01

201

Effects of flaxseed dietary supplementation on sperm quality and on lipid composition of sperm subfractions and prostatic granules in rabbit.  

PubMed

Lipids are the main structural/functional components of the sperm, and their composition may undergo a series of modifications in relation to either physiologic events (capacitation and acrosome reaction) and/or diet. The goals of the current study were (1) to investigate whether a flaxseed (FS) dietary supplementation could affect the lipid and fatty acid profile of sperm subfractions and of prostatic granules (PGs) and (2) to evaluate the effects of dietary FS on rabbit buck semen quality. Accordingly, 20 adult New Zealand White rabbits were fed ad libitum a control diet (CO) or a diet supplemented with 5% extruded FS. Integration of diet with FS, as a consequence of the linolenic acid (C18:3n-3; LNA; 56%), increased the dietary n-3/n-6 ratio and resulted in a substantial rearrangement of sperm fatty acid composition at the subcellular level, mainly of polyunsaturated fatty acid (PUFA)n-3 (8.3% vs. 14.3%, P<0.05). The lipid and fatty acid profiles of sperm tail membrane were the most affected, undergoing the following significant changes: (1) a reduction by half of linoleic acid (C18:2n-6; LA) and docosapentaenoic acid (22:5n-6; DPA), and a reduction of cholesterol (-70%); (2) a concomitant increase of LNA (+65%), docosahexaenoic acid (22:6n-3; DHA; +83%), and of oleic acid (C18:1n-9, +61%). As a consequence, the sperm of FS-fed rabbits had a twice higher n-3/n-6 ratio and phospholipid/cholesterol ratio compared with the control sperm. These changes might have been on the basis of the higher responsiveness to hypo-osmotic solution and, hence, the higher sperm track speed observed for the FS group. Also, the membrane integrity and viability of the LNA-enriched sperm were both improved. On the other hand, the presence of lignans in FS might have accounted for the reduction of sperm cholesterol in the semen of FS-treated rabbits. The responsiveness of sperm to acrosome reaction was not affected by the dietary treatment probably due to supranutritional level of vitamin E and to the higher number of PGs, which are known to play a key role in sperm capacitation. In conclusion, our data showed for the first time that the integration of FS into the rabbit diet may improve sperm quality by modifying the sperm lipid composition and that the sperm subfractions and the PGs respond differently to the FS-induced lipid manipulation. PMID:20034660

Mourvaki, E; Cardinali, R; Dal Bosco, A; Corazzi, L; Castellini, C

2010-03-15

202

Variation in Apical Hook Length Reflects the Intensity of Sperm Competition in Murine Rodents  

PubMed Central

Background Post-copulatory sexual selection has been shown to shape morphology of male gametes. Both directional and stabilizing selection on sperm phenotype have been documented in vertebrates in response to sexual promiscuity. Methodology Here we investigated the degree of variance in apical hook length and tail length in six taxa of murine rodents. Conclusions Tail sperm length and apical hook length were positively associated with relative testis mass, our proxy for levels of sperm competition, thus indicating directional post-copulatory selection on sperm phenotypes. Moreover, our study shows that increased levels of sperm competition lead to the reduction of variance in the hook length, indicating stabilizing selection. Hence, the higher risk of sperm competition affects increasing hook length together with decreasing variance in the hook length. Species-specific post-copulatory sexual selection likely optimizes sperm morphology. PMID:23844198

Šandera, Martin; Albrecht, Tomáš; Stopka, Pavel

2013-01-01

203

Protective effect of royal jelly on the sperm parameters and testosterone level and lipid peroxidation in adult mice treated with oxymetholone  

PubMed Central

Objectives : The aim of the present study was to evaluate protective effect of royal jelly on sperm parameters, testosterone level, and malondialdehyde (MDA) production in mice. Materials and Methods: Thirty-two adult male NMRI mice weighing 30±2 g were used. All the animals were divided into 4 groups. Control group: received saline 0.1 ml/mouse/day orally for 30 days. Royal jelly group (RJ): received royal jelly at dose of 100 mg/kg daily for 30 days orally. Oxymetholone group: the received Oxymetholone (OX) at dose of 5 mg/kg daily for 30 days orally. Royal jelly+Oxymetholone group: received royal jelly at dose of 100 mg/kg/day orally concomitant with OX administration. Sperm count, sperm motility, viability, maturity, and DNA integrity were analyzed. Furthermore, serum testosterone and MDA concentrations were determined. Results: In Oxymetholone group, sperm count, motility as well as testosterone concentration reduced significantly (p<0.05), while significant (p<0.05) increases in immature sperm, sperm with DNA damaged, and MDA concentration were announced in Oxymetholone group in comparison with control group and Royal jelly+Oxymetholone group. RJ caused partially amelioration in all of the above- mentioned parameters in Royal Jelly+Oxymetholone group. Conclusion: In conclusion, RJ may be used in combination with OX to improve OX-induced oxidative stress and male infertility. PMID:25050300

Zahmatkesh, Ensieh; Najafi, Gholamreza; Nejati, Vahid; Heidari, Reza

2014-01-01

204

SNAP and SIN-1 increase brain production of kynurenic acid.  

PubMed

The influence of nitric oxide (NO) donors, S-nitroso-N-acetylpenicillamine (SNAP), and 3-morpholinosydnonimine (SIN-1), on the central production of an endogenous glutamate receptor antagonist, kynurenic acid, was evaluated in vitro. In cortical slices, SNAP and SIN-1 potently increased the extracellular concentration of kynurenic acid. A free radical scavenger, l-ascorbate reversed this effect. Neither SNAP nor SIN-1 altered the activity of kynurenic acid biosynthetic enzymes, kynurenine aminotransferases (KAT I and II). These data reveal a novel aspect of the brain response to studied herein NO donors and suggest that in the milieu containing NO-related free radicals the formation of kynurenic acid is enhanced. PMID:17391664

Luchowski, Piotr; Urbanska, Ewa M

2007-06-01

205

Methods for increasing the production of ethanol from microbial fermentation  

DOEpatents

A stable continuous method for producing ethanol from the anaerobic bacterial fermentation of a gaseous substrate containing at least one reducing gas involves culturing a fermentation bioreactor anaerobic, acetogenic bacteria in a liquid nutrient medium; supplying the gaseous substrate to the bioreactor; and manipulating the bacteria in the bioreactor by reducing the redox potential, or increasing the NAD(P)H TO NAD(P) ratio, in the fermentation broth after the bacteria achieves a steady state and stable cell concentration in the bioreactor. The free acetic acid concentration in the bioreactor is maintained at less than 5 g/L free acid. This method allows ethanol to be produced in the fermentation broth in the bioreactor at a productivity greater than 10 g/L per day. Both ethanol and acetate are produced in a ratio of ethanol to acetate ranging from 1:1 to 20:1.

Gaddy, James L. (Fayetteville, AR); Arora, Dinesh K. (Fayetteville, AR); Ko, Ching-Whan (Fayetteville, AR); Phillips, John Randall (Fayetteville, AR); Basu, Rahul (Bethlehem, PA); Wikstrom, Carl V. (Fayetteville, AR); Clausen, Edgar C. (Fayetteville, AR)

2007-10-23

206

Long-term effects of triethylenemelamine exposure on mouse testis cells and sperm chromatin structure assayed by flow cytometry  

Microsoft Academic Search

The toxic and potentially mutagenic actions of triethylenemelamine (TEM) on mouse body and testis weights, testicular cell kinetics, sperm production, sperm head morphology, and sperm chromatin structure were assessed in two experiments. The first experiment examined effects of four dose levels of TEM, assayed 1, 4, or 10 wk after toxic exposure. In the second study, effects from five dosage

D. P. Evenson; R. K. Baer; L. K. Jost

1989-01-01

207

Zn2+ Increases Siderophore Production in Azotobacter vinelandii  

PubMed Central

When Azotobacter vinelandii was grown in the presence of low levels of iron, the addition of 20 or 40 ?M ZnSO4 caused earlier production of the catechol siderophores and a dramatic increase in the amount of azotobactin. The level of cellular iron was not significantly lowered in Zn2+ -grown cells, which suggested that Zn2+ was not causing more severe, or earlier, iron limitation. Also, Zn2+ did not appear to affect production of the high-molecular-weight outer membrane iron-repressible proteins that presumably function as ferrisiderophore receptors. Spectrophotometric examination of ion binding to the siderophores revealed that while the siderophores appeared to bind Zn2+, only in the case of azotochelin was iron unable to completely overcome any Zn2+ -induced changes in the absorption spectra. This appeared to rule out direct competition of Zn2+ with iron for binding to the siderophores. 55Fe uptake was depressed both in Zn2+ -grown cells and in Zn2+ -free cells to which Zn2+ was added during the uptake assay, except with azotobactin, with which the level of 55Fe uptake by Zn2+ -grown cells was close to control levels. These results suggested two possible sites where Zn2+ could be acting, one involving the biosynthesis of siderophores and possibly the genetic regulation of the iron assimilation system and the other involving an internal point common to iron assimilation by both high- and low-affinity iron uptake. Images PMID:16347766

Huyer, Marianne; Page, William J.

1988-01-01

208

Females of the grasshopper Chorthippus parallelus (Zett.) do not remate for fresh sperm  

PubMed Central

The evolution of female multiple mating is still a largely debated field. Among the benefits that have been proposed to explain this risky behaviour is the replenishment of sperm reserves. Apart from an increase in total sperm number, it can be an expression of post-copulatory mate choice or can be directed towards the uptake of fresh sperm. Using fresh sperm for fertilization instead of sperm aged by storage in the female genital tract may avoid a lowered fertilization capacity, an increase in deleterious effects or a skewed offspring sex ratio. We investigated the influence of sperm age on female fitness in the grasshopper Chorthippus parallelus, a species where females mate multiply. After copulation, females store sperm over the course of weeks until fertilization. An average ejaculate of 250 000 spermatozoa exponentially declined with time within the female's spermatheca. The number of days since copulation better explained the variation in actual sperm number than the number of pods or eggs laid. We investigated differences in female fitness parameters in two treatments. In the first, females were mated only once, while in the second, females always had freshly ejaculated sperm available. Although in our experiment, multiply mated females had heavier offspring than singly mated females, egg number per pod, hatching and fertilization success, their composite effects and offspring sex ratio did not vary with respect to season or sperm age. We therefore reject the hypothesis that the reason for remating in females of this species is the uptake of fresh sperm.

Reinhardt, K.; hler, G. K; Schumacher, J.

1999-01-01

209

Earthworms increase plant production: a meta-analysis.  

PubMed

To meet the challenge of feeding a growing world population with minimal environmental impact, we need comprehensive and quantitative knowledge of ecological factors affecting crop production. Earthworms are among the most important soil dwelling invertebrates. Their activity affects both biotic and abiotic soil properties, in turn affecting plant growth. Yet, studies on the effect of earthworm presence on crop yields have not been quantitatively synthesized. Here we show, using meta-analysis, that on average earthworm presence in agroecosystems leads to a 25% increase in crop yield and a 23% increase in aboveground biomass. The magnitude of these effects depends on presence of crop residue, earthworm density and type and rate of fertilization. The positive effects of earthworms become larger when more residue is returned to the soil, but disappear when soil nitrogen availability is high. This suggests that earthworms stimulate plant growth predominantly through releasing nitrogen locked away in residue and soil organic matter. Our results therefore imply that earthworms are of crucial importance to decrease the yield gap of farmers who can't -or won't- use nitrogen fertilizer. PMID:25219785

van Groenigen, Jan Willem; Lubbers, Ingrid M; Vos, Hannah M J; Brown, George G; De Deyn, Gerlinde B; van Groenigen, Kees Jan

2014-01-01

210

Proteins Involved in Motility and Sperm-Egg Interaction Evolve More Rapidly in Mouse Spermatozoa  

PubMed Central

Proteomic studies of spermatozoa have identified a large catalog of integral sperm proteins. Rapid evolution of these proteins may underlie adaptive changes of sperm traits involved in different events leading to fertilization, although the selective forces underlying such rapid evolution are not well understood. A variety of selective forces may differentially affect several steps ending in fertilization, thus resulting in a compartmentalized adaptation of sperm proteins. Here we analyzed the evolution of genes associated to various events in the sperm’s life, from sperm formation to sperm-egg interaction. Evolutionary analyses were performed on gene sequences from 17 mouse strains whose genomes have been sequenced. Four of these are derived from wild Mus musculus, M. domesticus, M. castaneus and M. spretus. We found a higher proportion of genes exhibiting a signature of positive selection among those related to sperm motility and sperm-egg interaction. Furthermore, sperm proteins involved in sperm-egg interaction exhibited accelerated evolution in comparison to those involved in other events. Thus, we identified a large set of candidate proteins for future comparative analyses of genotype-phenotype associations in spermatozoa of species subjected to different sexual selection pressures. Adaptive evolution of proteins involved in motility could be driven by sperm competition, since this selective force is known to increase the proportion of motile sperm and their swimming velocity. On the other hand, sperm proteins involved in gamete interaction could be coevolving with their egg partners through episodes of sexual selection or sexual conflict resulting in species-specific sperm-egg interactions and barriers preventing interspecies fertilization. PMID:24608277

Vicens, Alberto; Lüke, Lena; Roldan, Eduardo R. S.

2014-01-01

211

Sperm storage mediated by cryptic female choice for nuptial gifts.  

PubMed

Polyandrous females are expected to discriminate among males through postcopulatory cryptic mate choice. Yet, there is surprisingly little unequivocal evidence for female-mediated cryptic sperm choice. In species in which nuptial gifts facilitate mating, females may gain indirect benefits through preferential storage of sperm from gift-giving males if the gift signals male quality. We tested this hypothesis in the spider Pisaura mirabilis by quantifying the number of sperm stored in response to copulation with males with or without a nuptial gift, while experimentally controlling copulation duration. We further assessed the effect of gift presence and copulation duration on egg-hatching success in matings with uninterrupted copulations with gift-giving males. We show that females mated to gift-giving males stored more sperm and experienced 17% higher egg-hatching success, compared with those mated to no-gift males, despite matched copulation durations. Uninterrupted copulations resulted in both increased sperm storage and egg-hatching success. Our study confirms the prediction that the nuptial gift as a male signal is under positive sexual selection by females through cryptic sperm storage. In addition, the gift facilitates longer copulations and increased sperm transfer providing two different types of advantage to gift-giving in males. PMID:24266042

Albo, Maria J; Bilde, Trine; Uhl, Gabriele

2013-12-01

212

Sperm storage mediated by cryptic female choice for nuptial gifts  

PubMed Central

Polyandrous females are expected to discriminate among males through postcopulatory cryptic mate choice. Yet, there is surprisingly little unequivocal evidence for female-mediated cryptic sperm choice. In species in which nuptial gifts facilitate mating, females may gain indirect benefits through preferential storage of sperm from gift-giving males if the gift signals male quality. We tested this hypothesis in the spider Pisaura mirabilis by quantifying the number of sperm stored in response to copulation with males with or without a nuptial gift, while experimentally controlling copulation duration. We further assessed the effect of gift presence and copulation duration on egg-hatching success in matings with uninterrupted copulations with gift-giving males. We show that females mated to gift-giving males stored more sperm and experienced 17% higher egg-hatching success, compared with those mated to no-gift males, despite matched copulation durations. Uninterrupted copulations resulted in both increased sperm storage and egg-hatching success. Our study confirms the prediction that the nuptial gift as a male signal is under positive sexual selection by females through cryptic sperm storage. In addition, the gift facilitates longer copulations and increased sperm transfer providing two different types of advantage to gift-giving in males. PMID:24266042

Albo, Maria J.; Bilde, Trine; Uhl, Gabriele

2013-01-01

213

Cigarette smoke extract immobilizes human spermatozoa and induces sperm apoptosis.  

PubMed

Cigarette smoking by the male partner adversely affects assisted reproductive techniques, suggesting that it may damage sperm chromatin/DNA and consequently embryo development. The effects of graded concentrations of research cigarettes smoke extract (CSE) on motility, mitochondrial membrane potential (MMP), chromatin integrity and apoptosis were evaluated in spermatozoa obtained from 13 healthy, non-smoking men with normal sperm parameters, by flow cytometry. CSE suppressed sperm motility in a concentration- and time-dependent manner and increased the number of spermatozoa with low MMP, the main source of energy for sperm motility. In addition, CSE had a detrimental effect on sperm chromatin condensation and apoptosis. Indeed, it increased the number of spermatozoa with phosphatidylserine externalization, an early apoptotic sign, and fragmented DNA, a late apoptotic sign, in a concentration- and time-dependent manner. These effects of CSE were of similar or even greater magnitude to those obtained following incubation with tumour necrosis factor-alpha, a cytokine known for its negative impact on sperm function, used as positive control. Since transmission of smoking-induced sperm DNA alterations has been found in pre-implantation embryos, and this may predispose offspring to a greater risk of malformations, cancer and genetic diseases, men seeking to father a child are recommended to give up smoking. PMID:19909599

Calogero, Aldo; Polosa, Riccardo; Perdichizzi, Anna; Guarino, Francesca; La Vignera, Sandro; Scarfia, Alessia; Fratantonio, Enza; Condorelli, Rosita; Bonanno, Oriana; Barone, Nunziata; Burrello, Nunziatina; D'Agata, Rosario; Vicari, Enzo

2009-10-01

214

Current Status of Sperm Cryopreservation in Biomedical Research Fish Models: Zebrafish, Medaka, and Xiphophorus*  

PubMed Central

Aquarium fishes are becoming increasingly important because of their value in biomedical research and the ornamental fish trade, and because many have become threatened or endangered in the wild. This review summarizes the current status of sperm cryopreservation in three fishes widely used in biomedical research: zebrafish, medaka, and live-bearing fishes of the genus Xiphophorus, and will focus on the needs and opportunities for future research and application of cryopreservation in aquarium fish. First, we summarize the basic biological characteristics regarding natural habitat, testis structure, spermatogenesis, sperm morphology, and sperm physiology. Second, we compare protocol development of sperm cryopreservation. Third, we emphasize the importance of artificial fertilization in sperm cryopreservation to evaluate the viability of thawed sperm. We conclude with a look to future research directions for sperm cryopreservation and the application of this technique in aquarium species. PMID:18691673

Yang, Huiping; Tiersch, Terrence R.

2009-01-01

215

Identification of Peroxiredoxin-5 in Bovine Cauda Epididymal Sperm  

PubMed Central

Developing spermatozoa require a series of post-testicular modifications within the luminal environment of the epididymis to achieve maturation; this involves several surface modifications including changes in plasma membrane lipids, proteins, carbohydrates, and alterations in the outer acrosomal membrane. Epididymal maturation can therefore allow sperm to gain forward motility and fertilization capabilities. The objective of this study was to identify maturation dependent protein(s) and to investigate their role with the production of functionally competent spermatozoa. Lectin blot analyses of caput and cauda sperm plasma membrane fractions identified a 17.5kDa Wheat Germ Agglutinin (WGA) binding polypeptide present in the cauda sperm plasma membrane not in the caput sperm plasma membrane. Among the several WGA stained bands, the presence of a 17.5kDa WGA binding polypeptide band was detected only in cauda epididymal fluid not in caput epididymal fluid suggesting that the 17.5kDa WGA-binding polypeptide is secreted from the cauda epididymis and binds to the cauda sperm plasma membrane during epididymal transit. Proteomic identification of the 17.5kDa polypeptide yielded 13 peptides that matched the sequence of peroxiredoxin-5 (PRDX5) protein (Bos Taurus). We propose that bovine cauda sperm PRDX5 acts as an antioxidant enzyme in the epididymal environment, which is crucial in protecting the viable sperm population against the damage caused by endogeneous or exogeneous peroxide. PMID:24186847

Nagdas, Subir K; Buchanan, Teresa; Raychoudhury, Samir

2013-01-01

216

Royal jelly increases collagen production in rat skin after ovariectomy.  

PubMed

Royal jelly (RJ) is a honeybee product that contains proteins, carbohydrates, fats, free amino acids, vitamins, and minerals. RJ has been reported to have antitumor, antibacterial, and wound-healing activities. We previously reported that RJ enhanced the migration of human dermal fibroblasts and altered the levels of cholesterol and sphinganine in an in vitro wound-healing model in addition to regulating skin photoaging following exposure to ultraviolet-B radiation. We established an animal model of skin aging in the context of estrogen deficiency and assessed the antiaging effects of RJ on skin. To establish an in vivo model of skin aging, bilateral ovariectomies were performed in 12-week-old virgin female Sprague-Dawley rats. Induction of osteoporosis was confirmed through two-dimensional images of the trabecular bone in the left femoral necks using microcomputed tomography. The protective effects of RJ ovariectomy-induced skin aging were examined by determining the protein expression of type I procollagen and matrix metalloproteinase (MMP)-1. The collagen content and epidermal thickness of skin tissue were measured by staining techniques. There was a significant difference in weight between sham-operated and ovariectomized groups. Food efficiency ratio did not differ significantly among the groups. The level of procollagen type I protein was increased in the dorsal skin of ovariectomized rats fed with a dietary supplement containing 1% RJ extract, but the level of MMP-1 was not altered. In particular, the amount of collagen recovered was close to the normal level. RJ may protect against skin aging by enhancing collagen production in rats with ovariectomy-induced estrogen deficiency. PMID:22468645

Park, Hye Min; Cho, Min Hyoung; Cho, Yunhi; Kim, Sun Yeou

2012-06-01

217

Biochemical and topological analysis of bovine sperm cells induced by low power laser irradiation  

NASA Astrophysics Data System (ADS)

Low-level laser irradiation (LLLI) increases ATP production and energy supply to the cell which could increase sperm motility, acrossomal reaction and consequently the fertilizing potential. The aim of this study was to characterize the biochemical and topological changes induced by low power laser irradiation on bull sperm cells. Post-thawing sperm were irradiated with a 633nm laser with fluence rates of 30, 150 and 300mJ.cm-2 (power of 5mW for 1, 5 and 10minutes, respectively); 45, 230, and 450mJ.cm-2 (7.5mW for 1, 5 and 10 minutes); and 60, 300 and 600mJ.cm-2 (10mW for 1, 5 and 10 minutes). Biochemical and metabolical changes were analyzed by FTIR and flow cytometry; oxygen reactive species production was assessed by TBARS and the morphological changes were evaluated by AFM. Motility had no difference among times or powers of irradiation. Increasing in ROS generation was observed with power of 5mW compared to 7.5 and 10mW, and with 10min of irradiation in comparison with 5 and 1min of irradiation. This higher ROS generation was related to an increase in acrossomal and plasma membrane damage. FTIR results showed that the amount of lipids was inversely proportional to the quantity of ROS generated. AFM images showed morphological differences in plasma/acrossomal membrane, mainly on the equatorial region. We conclude that LLLI is an effective method to induce changes on sperm cell metabolism but more studies are necessary to establish an optimal dose to increase the fertility potential of these cells.

Dreyer, T. R.; Siqueira, A. F. P.; Magrini, T. D.; Fiorito, P. A.; Assumpção, M. E. O. A.; Nichi, M.; Martinho, H. S.; Milazzotto, M. P.

2011-07-01

218

Frozen-thawed rhinoceros sperm exhibit DNA damage shortly after thawing when assessed by the sperm chromatin dispersion assay.  

PubMed

This study reports on the successful validation (via in situ nick translation and neutral comet assay) of the equine Sperm-Halomax kit as an appropriate methodology for the assessment of sperm DNA fragmentation in three species of rhinoceros. Rhinoceros sperm nuclei with fragmented DNA (validated using in situ nick translation) were evident as large halos with dispersed DNA fragments, whereas those with nonfragmented DNA displayed small halos of nondispersed DNA within the microgel. There was a high correlation (r) of 0.974 (R(2) value=0.949; P<0.01; n=16) between the respective assessments of the Sperm Chromatin Dispersion test (SCDt) and the neutral comet assay. Application of the SCDt to determine the DNA fragmentation dynamics of rhinoceros (n=6) sperm frozen in liquid nitrogen vapor and incubated postthaw at 37 degrees C for up to 48 h to mimic in vitro conditions in the female reproductive tract, revealed an increase (P=0.001) in DNA damage, as soon as 4h after the start of incubation. Linear regression equations were calculated for all six rhinoceroses over the first 6h of incubation and revealed individual animal variation. Freshly collected and incubated (37 degrees C) rhinoceros (n=3) sperm had no increase in the basal level of DNA fragmentation for up to 48 h, indicating that the cryopreservation of rhinoceros sperm in liquid nitrogen vapor, as used in this study, appeared to result in freeze-thaw DNA damage. PMID:19560805

Portas, T; Johnston, S D; Hermes, R; Arroyo, F; López-Fernadez, C; Bryant, B; Hildebrandt, T B; Göritz, F; Gosalvez, J

2009-09-15

219

Mammalian Sperm Fertility Related Proteins  

PubMed Central

Infertility is an important aspect of human and animal reproduction and still presents with much etiological ambiguity. As fifty percent of infertility is related to the male partner, molecular investigations on sperm and seminal plasma can lead to new knowledge on male infertility. Several comparisons between fertile and infertile human and other species sperm proteome have shown the existence of potential fertility markers. These proteins have been categorized into energy related, structural and other functional proteins which play a major role in sperm motility, capacitation and sperm-oocyte binding. The data from these studies show the impact of sperm proteome studies on identifying different valuable markers for fertility screening. In this article, we review recent development in unraveling sperm fertility related proteins. PMID:24151436

Ashrafzadeh, Ali; Karsani, Saiful Anuar; Nathan, Sheila

2013-01-01

220

Effects of environment factors on initiation of sperm motility in sea cucumber Apostichopus japonicus (Selenka)  

NASA Astrophysics Data System (ADS)

Sperm of sea cucumber Apostichopus japonicus (Selenka) were quiescent in electrolyte NaCl solution and artificial seawater (ASW) and nonelectrolyte glucose and mannitol solutions when the osmolality was less than 200 mOsm kg-1. The sperm started to be motile as a result of increased osmolality, indicating an osmolality-dependent initiation of sperm motility in sea cucumber. After a brief incubation in hypotonic NaCl and glucose solutions with osmolalities of 200 and 400 mOsm kg-1, sperm lost partial motile ability. Sperm became immobilized when pH was 6.0 in NaCl, glucose and mannitol solutions, suggesting that an H+ release is involved in sperm activation. The decreased pH had no effect on the percentage of motile sperm in ASW, whereas it delayed the time period to reach the maximum motility (motilitymax). Extracellular Ca2+ in electrolyte solutions was not essential for motility stimulation but shortened the time of reaching motilitymax. When Ca2+ was mixed in nonelectrolyte solutions the sperm motility was completely suppressed. The K+ channel blocker, quinine, suppressed the sperm motility in electrolyte solution, showing a possible involvement of K+ transport in the process. High K+ concentration did not affect the sperm motility in NaCl solution, but decreased it in ASW and almost entirely suppressed it in nonelectrolyte solutions. The different effects of pH and K+ in ASW and NaCl solution indicate that external ions may also regulate sperm motility.

Yu, Li; Shao, Mingyu; Bao, Zhenmin; Hu, Jingjie; Zhang, Zhifeng

2011-06-01

221

Sperm Whale Project  

NSDL National Science Digital Library

This site describes an award-winning project in Homer, Alaska. After a sperm whale carcass washed ashore, a museum-school collaboration implemented a five-year cross-disciplinary marine science education project using major grant funding. Students worked with museum staff, scientists, public agencies and the community to research the whale, preserve, articulate and mount its skeleton. They developed exhibits, school and community education programs interpreting the whale and promoting ocean conservation in the region.

222

Lipids of the sperm plasma membrane: from polyunsaturated fatty acids considered as markers of sperm function to possible scavenger therapy.  

PubMed

This article is, in part, a review of present knowledge regarding the lipid metabolism of the sperm cell and the lipid composition of the sperm plasma membrane. It is also a summary of our research on this topic, reporting published and unpublished data. The article tries to cover both basic and clinical research. Sperm cells use lipid metabolic pathways for the production of part of their energy. The double leaflets of the membrane are not simply a passive, bilayer, lipidic film in which the receptors receive their molecular specific signals, but are a very specialized structure. Complete maturation of the lipids of the sperm cell membrane is reached after passage of the spermatozoon through the epididymis. A specific composition of phospholipids and a significant concentration of polyunsaturated fatty acids (PUFA) have been shown to be present in sperm membranes. Plasmalogen is a special kind of phospholipid found exclusively in spermatozoa and other cells with the capacity to react promptly to stimuli. In addition, we have found a high concentration of the n-3 PUFA family in the sperm membrane. Seminal plasma has a highly specialized scavenger system that defends the sperm membrane against lipoperoxidation. Various pathologies and systemic predisposition can lead to an antioxidant/pro-oxidant disequilibrium. Clinical trials with natural scavengers could be a useful research area in which to seek a treatment for these pathologies. Of the natural scavengers, glutathione has been shown to restore the physiological constitution of PUFA in the cell membrane under certain conditions. PMID:9079417

Lenzi, A; Picardo, M; Gandini, L; Dondero, F

1996-01-01

223

Increasing transcurium production efficiency through direct resonance shielding  

SciTech Connect

The Radiochemical Engineering Development Center at Oak Ridge National Laboratory is the world s leader in production of 252Cf. This and other heavy actinides are produced by irradiation of mixed curium/americium targets in the High Flux Isotope Reactor. Due to the strong dependence of isotopic cross sections upon incoming neutron energy, the efficiency with which an isotope is transmuted is highly dependent upon the neutron flux energy spectrum and intensities. There are certain energy ranges in which the rate of fissions in feedstock materials can be minimized relative to the rate of (n, ) absorptions. It is shown that by perturbing the flux spectrum, it is possible to alter the net consumption of curium feedstock, as well as the yields of key isotopes for the heavy element research program, such as 249Bk and 252Cf. This flux spectrum perturbation is accomplished by means of focused resonance shielding through the use of filter materials. It is further shown that these perturbations can alter the target yields in a significant way, increasing the amount of 252Cf produced per unit curium consumption by over 40%.

Hogle, Susan L [ORNL; Maldonado, G Ivan [ORNL; Alexander, Charles W [ORNL

2013-01-01

224

Impaired swimming behaviour and morphology of sperm from barn swallows Hirundo rustica in Chernobyl.  

PubMed

We investigated the motility and morphology of live sperm from barn swallows Hirundo rustica breeding in radioactively contaminated areas around Chernobyl and control areas in Ukraine in order to test the hypothesis that swimming behaviour and morphology of sperm was impaired by radioactive contamination. We obtained sperm samples from 98% of sampled birds, thus avoiding sampling bias due to the fraction of males not producing sperm samples. Analyses of within- and between-sample repeatability revealed significant and intermediate to large estimates for all sperm parameters. There were significant differences between the Chernobyl area and the control area for two of 11 sperm behaviour parameters, and significant interactions between area and year for six of these parameters. The proportion of sperm with abnormal morphology was elevated in barn swallows from Chernobyl. A principal component (PC) analysis revealed four significant axes that explained 88% of the variance in sperm behaviour parameters. One of these principal components differed between areas, and three components showed significant year by area interactions. PC2 representing the frequency of slow sperm increased with increasing radiation in one year, but not another. PC3 representing sperm with high linearity, small amplitude of lateral head displacement and low track velocity decreased with increasing background radiation level. PC4 reflecting a large proportion of static sperm with high beat cross frequency increased with increasing background radiation level. Sperm behaviour as reflected by principal components was predictable among years from information on level of radiation, and it was predictable among sites in different years. These results are consistent with the hypothesis that sperm behaviour and morphology have been affected by radiation due to the Chernobyl accident. PMID:18218334

Møller, A P; Mousseau, T A; Lynn, C; Lynnn, C; Ostermiller, S; Rudolfsen, G

2008-02-29

225

Freezing of stallion epididymal sperm.  

PubMed

Inseminations with frozen-thawed epididymal sperm have resulted in low-pregnancy rates of mares. If fertility of epididymal sperm could be improved, it would help to preserve genetic material from stallions that have suffered severe injuries, been castrated or have died. The aim of the present study was to investigate the effect of different extenders and pre-freezing addition of capacitation media on freezability of epididymal sperm and on storage at 5 degrees C for 24h. In experiment 1, epididymal sperm samples were diluted and subsequently frozen with three different extenders: Botu-Crio, EDTA-Lactose and INRA-82. Motility analysis using computer assisted sperm analyzer (CASA) demonstrated better motility for sperm in Botu-Crio than in the other extenders; EDTA-Lactose yielded better motility than INRA-82 on most evaluated parameters. There was no difference in membrane integrity among the studied extenders. From 18 inseminated mares, 12 (66%) were pregnant 15 days after AI with frozen-thawed epididymal sperm showing that Botu-Crio was able to maintain the fertility potential. In experiment 2, the effect of incubation of epididymal sperm before freezing in three capacitation media (Fert Talp, Sperm Talp, Talp+Progesterone), seminal plasma, or control was tested. Based on post-thaw motility evaluation by CASA, samples incubated in Sperm Talp showed better motility values. There were no differences in plasma or acrosomal membranes or in mitochondrial potential among groups. We concluded that Botu-Crio was better than the other extenders in the ability to preserve epididymal sperm and that pre-freeze addition of Sperm Talp was also beneficial. PMID:18556154

Papa, F O; Melo, C M; Fioratti, E G; Dell'aqua, J A; Zahn, F S; Alvarenga, M A

2008-09-01

226

Metal ions and human sperm mannose receptors.  

PubMed

Zinc and lead concentrations were measured in seminal plasma from fertile donors, infertile men with varicocoele and men undergoing work-ups for in vitro fertilization. Ejaculated spermatozoa from these subjects were incubated in vitro with various metal ions and/or dibromoethane and dibromochloropropane. Mannose receptor expression was correlated with metal and toxicant levels. Sperm distributions of potassium channels were compared with lead ions and calcium channels with zinc ions. Mannose receptor expression by capacitated spermatozoa increased linearly with seminal plasma zinc levels, and correlated inversely with lead levels. Cobalt had no effect on mannose receptor expression, but nickel had a concentration-dependent biphasic effect. Mannose receptor expression was not affected by dibromoethane and dibromochloropropane if the cholesterol content of the sperm membrane was high, but mannose receptor expression was decreased in low cholesterol spermatozoa by exposures below estimated permissive exposure limits. Potassium channels and lead ions co-localized over the entire head of human spermatozoa, while both calcium channels and zinc ions were confined to the equatorial segment of the head. Mannose receptor expression on the external surface of the human sperm plasma membrane is a biomarker for the effects of transition and heavy metals and organic toxicants on sperm fertility potential. PMID:11021525

Benoff, S; Cooper, G W; Centola, G M; Jacob, A; Hershlag, A; Hurley, I R

2000-09-01

227

Cryopreservation of epididymal stallion sperm.  

PubMed

Any event that makes semen collection or mating impossible, such as death, castration, or injury, may terminate a stallion's breeding career. Fortunately, stallion sperm which are capable of fertilization can be harvested from the epididymis, and frozen for future use. However, the fertility of frozen-thawed epididymal sperm has been found to be lower than that of ejaculated sperm. Therefore, this study aimed to optimize the fertility of frozen epididymal stallion sperm by investigating the effects of different cryoprotectants and freezing protocols on sperm quality. Dimethylformamide was tested alone or combination with pasteurized egg yolk as substitute of fresh egg yolk. In addition, the effect of the pre-freeze stabilization on sperm quality was analyzed. Heterospermic samples obtained from stallion epididymis were collected and cryopreserved in lactose-egg-yolk extender or in the same extender with varying content of cryoprotectant and content of egg yolk, stabilized and no-stabilized. Sperm motility, viability, hypoosmotic swelling test (HOST) and acrosome integrity were evaluated post-thawing. No improvement was observed on the replacement of fresh yolk by pasteurized egg yolk, whereas the results suggest that dimethylformamide is a cryoprotectant suitable for cryopreservation of equine epididymal semen, even better than glycerol. In addition, we found that the stabilization before freezing on epididymal stallion sperm, can improve sperm quality parameters. PMID:24412395

Olaciregui, M; Gil, L; Montón, A; Luño, V; Jerez, R A; Martí, J I

2014-02-01

228

Mating system does not predict permanent sperm depletion in black widow spiders.  

PubMed

Variation in sperm production is strongly influenced by mating system across taxa. Recent work in spiders suggests that males of some species show termination of spermatogenesis before their adult molt and thus an inability to produce sperm after maturation. This permanent sperm depletion (PSD) has been hypothesized to co-occur with monogyny, genital mutilation, or sexual cannibalism because the maintenance of continual sperm supplies is not necessary for species where males can expect only one mating opportunity. Here we test this hypothesis in two congeners exhibiting genital mutilation: the sexually cannibalistic, monogynous Australian redback spider Latrodectus hasselti and the polygynous Western black widow Latrodectus hesperus. We report that PSD does not occur in adult males of either species, and show that males transfer sperm into their copulatory organs multiple times as adults. These data suggest evolutionary links between mating system and investment in sperm production may be more complex than currently appreciated. PMID:23607304

Modanu, Maria; Michalik, Peter; Andrade, Maydianne C B

2013-05-01

229

Effect of sperm diluents on the acrosome reaction in canine sperm.  

PubMed

In this study we investigated the influence of sperm diluting media and temperature on the incidence of the acrosome reaction in dog sperm. Ejaculates were collected from 5 dogs, diluted with six different media and then incubated at 37 degrees C and 20 degrees C. Fluorescein isothiocynate conjugated peanut agglutinin (FITC-PNA) and ethidium homodimer as a vital stain were used in combination to determine the acrosomal status of viable spermatozoa, the technique was validated using electron microscopy. The outer acrosomal membrane of dog spermatozoa was shown to be the specific binding site for FITC-PNA. After 6 h of incubation, ejaculates diluted in media with a high Ca2+ concentration showed a significantly higher percentage (means +/- SD) of acrosome reacted spermatozoa [64 +/- 7 and 58 +/- 9 in sperm capacitation medium with (SP-TALP-1) and without BSA (SP-TALP-2), respectively] than those diluted in media with a low Ca2+ concentration [36 +/- 5, 39 +/- 4, 18 +/- 2 and 20 +/- 4 in Canine Capacitation Medium (CCM), Egg Yolk Tris dog semen extender (EXT-1), Modified Egg Yolk Tris extender (EXT-2) and Modified CCM (MCCM), respectively]. The increase in the percentage of acrosome reaction (AR) was slower at 20 degrees C than at 37 degrees C. In addition, the percentage of viable acrosome reacted spermatozoa increased significantly from 19 +/- 5 and 22 +/- 3 in non-bound sperm to 27 +/- 4 and 30 +/- 6 in zona pellucida bound sperm (diluted in EXT-2 and MCCM, respectively). We conclude that the composition of the spermatozoa diluent has a marked effect on the incidence of the acrosome reaction. Therefore, both the media used to dilute dog sperm and the temperature at which the spermatozoa are handled are important factors to consider when processing spermatozoa for artificial insemination, IVF procedures or preservation. PMID:10735044

Sirivaidyapong, S; Cheng, F P; Marks, A; Voorhout, W F; Bevers, M M; Colenbrander, B

2000-02-01

230

GMOs: Prospects for Productivity Increases in Developing Countries  

Microsoft Academic Search

There are two mechanisms by which modern genetically modified organism (GMO) products can affect productivity in developing countries. The first is the ‘Genes for Rent’ mechanism where a recipient country agrees with a GMO company to incorporate a GMO product (e.g., a Bt gene in cotton varieties) and pay a technology fee. The second is the ‘Transgenic Breeding’ mechanism in

Robert E. Evenson

2004-01-01

231

Characterization of Na+K+-ATPase in bovine sperm.  

PubMed

Existing as a ubiquitous transmembrane protein, Na(+)K(+)-ATPase affects sperm fertility and capacitation through ion transport and a recently identified signaling function. Functional Na(+)K(+)-ATPase is a dimer of ? and ? subunits, each with isoforms (four and three, respectively). Since specific isoform pairings and locations may influence or indicate function, the objective of this study was to identify and localize subunits of Na(+)K(+)-ATPase in fresh bull sperm by immunoblotting and immunocytochemistry using antibodies against ?1 and 3, and all ? isoforms. Relative quantity of Na(+)K(+)-ATPase in head plasma membranes (HPM's) from sperm of different bulls was determined by densitometry of immunoblot bands, and compared to bovine kidney. Sperm and kidney specifically bound all antibodies at kDa equivalent to commercial controls, and to additional lower kDa bands in HPM. Immunofluorescence of intact sperm confirmed that all isoforms were present in the head region of sperm and that ?3 was also uniformly distributed post-equatorially. Permeabilization exposing internal membranes typically resulted in an increase in fluorescence, indicating that some antibody binding sites were present on the inner surface of the HPM or the acrosomal membrane. Deglycosylation of ?1 reduced the kDa of bands in sperm, rat brain and kidney, with the kDa of the deglycosylated bands differing among tissues. Two-dimensional blots of ?1 revealed three distinct spots. Based on the unique quantity, location and structure Na(+)K(+)-ATPase subunits in sperm, we inferred that this protein has unique functions in sperm. PMID:22284223

Hickey, Katie D; Buhr, Mary M

2012-04-15

232

Sperm ultrastructure, morphometry, and abnormal morphology in American black bears (Ursus americanus).  

PubMed

The objective of this study was to describe sperm ultrastructure, morphometry, and abnormal morphology in American black bears. Electroejaculation was successful in 53.8% (7/13) of the attempts, but urine contamination was common. Epididymal sperm samples were also obtained from five bears. Sperm had a paddle-like head shape and the ultrastructure was similar to that of most other mammals. The most striking particularity of black bear sperm ultrastructure was a tightening of the nucleus in the equatorial region. Although the differences were not significant in all bears, the overall decrease in sperm nucleus dimensions during transport from the caput epididymis to the cauda suggested increasing compaction of the nucleus during maturation. For ejaculated sperm, nucleus length, width, and base width were 4.9, 3.7, and 1.8 ?m, respectively, whereas sperm head length, width, and base width were 6.6, 4.8, and 2.3 ?m, and midpiece, tail (including midpiece), and total sperm lengths were 9.8, 68.8, and 75.3 ?m. Evaluation of sperm cytoplasmic droplets in the epididymis revealed that proximal droplets start migrating toward a distal position in the caput epididymis and that the process was mostly completed by the time sperm reached the cauda epididymis. The proportion of morphologically normal sperm in the ejaculate was 35.6%; the most prevalent sperm defects were distal cytoplasmic droplets and bent/coiled tails. The morphology of abnormal sperm and the underlying ultrastructural defects were similar to that in other large domestic animals thus suggesting similar underlying pathogenesis of specific sperm defects and similar effects on fertility. PMID:20708230

Brito, L F C; Sertich, P L; Stull, G B; Rives, W; Knobbe, M

2010-11-01

233

Increasing cropping system diversity balances productivity, profitability and environmental health  

Technology Transfer Automated Retrieval System (TEKTRAN)

Balancing productivity, profitability, and environmental health is a key challenge for agricultural sustainability. Most crop production systems in the United States are characterized by low species and management diversity, high use of fossil energy and agrichemicals, and can have large negative im...

234

Research Strategies for Increasing Productivity of Intensively Managed  

E-print Network

plantations in the United States, with smaller pockets in the Midwest and other regions. Projected increases and bioenergy are likely to increase pressure on forests and create incentives for enhancing their pro

235

Biodiversity Increases the Productivity and Stability of Phytoplankton Communities  

PubMed Central

Global biodiversity losses provide an immediate impetus to elucidate the relationships between biodiversity, productivity and stability. In this study, we quantified the effects of species richness and species combination on the productivity and stability of phytoplankton communities subject to predation by a single rotifer species. We also tested one mechanism of the insurance hypothesis: whether large, slow-growing, potentially-defended cells would compensate for the loss of small, fast-growing, poorly-defended cells after predation. There were significant effects of species richness and species combination on the productivity, relative yield, and stability of phytoplankton cultures, but the relative importance of species richness and combination varied with the response variables. Species combination drove patterns of productivity, whereas species richness was more important for stability. Polycultures containing the most productive single species, Dunaliella, were consistently the most productive. Yet, the most species rich cultures were the most stable, having low temporal variability in measures of biomass. Polycultures recovered from short-term negative grazing effects, but this recovery was not due to the compensation of large, slow-growing cells for the loss of small, fast-growing cells. Instead, polyculture recovery was the result of reduced rotifer grazing rates and persisting small species within the polycultures. Therefore, although an insurance effect in polycultures was found, this effect was indirect and unrelated to grazing tolerance. We hypothesize that diverse phytoplankton assemblages interfered with efficient rotifer grazing and that this “interference effect” facilitated the recovery of the most productive species, Dunaliella. In summary, we demonstrate that both species composition and species richness are important in driving patterns of productivity and stability, respectively, and that stability in biodiverse communities can result from an alteration in consumer functioning. Our findings underscore the importance of predator-prey dynamics in determining the relationships between biodiversity, productivity and stability in producer communities. PMID:23173059

Corcoran, Alina A.; Boeing, Wiebke J.

2012-01-01

236

Effect of caffeine on motility and vitality of sperm and in vitro fertilization of outbreed mouse in T6 and M16 media  

PubMed Central

Background: Caffeine increases the CAMP production that stimulates spermatozoa movement. Caffeine is also used for induction of in vitro acrosome reaction in mammalian spermatozoa, an important step in achieving fertilization. Objective: The aim of this study was to assess the effect of caffeine on sperm's motility, vitality and laboratory fertilization rates in mouse in two T6 and M16 media. Materials and Methods: Epididymal mouse sperms were collected and treated by caffine in T6 and M16 media and their motility and vitality rates were evaluated. The pretreated sperms were added to oocytes in T6 and M16 media with and without caffeine and fertilization rates were recorded after 24 hours incubation. Results: Sperm's motility (81.7±1.67%) and vitality (88.7±1.33%) rates and percentage of fertilized oocytes (67.52±8.16%) in T6 medium plus caffeine compare to control group have increased and shown significant differences at p?0.01. While the percentages of these parameters in M16 medium supplemented with caffeine were 68.3±6.01%, 78±6.11%, and 42.6±12.96 respectively and in comparison to control group (M16 without caffeine) have not shown significant differences. Conclusion: Addition of caffeine to T6 medium promotes the sperm's motility and vitality and enhances fertilization and early in vitro development of mouse embryos. This article extracted from M.Sc. thesis. (Narges Navabi) PMID:24639814

Nabavi, Narges; Todehdehghan, Fatemeh; Shiravi, Abdollhossein

2013-01-01

237

Could increased boreal forest ecosystem productivity offset carbon losses from increased disturbances?  

Microsoft Academic Search

To understand how boreal forest carbon (C) dynamics might respond to anticipated climatic changes, we must consider two important processes. First, projected climatic changes are expected to increase the frequency of fire and other natural disturbances that would change the forest age-class structure and reduce forest C stocks at the landscape level. Second, global change may result in increased net

Werner A. Kurz; Graham Stinson; Greg Rampley

2009-01-01

238

Addition of cholesterol-loaded cyclodextrins to the thawing extender: effects on boar sperm quality.  

PubMed

The aim of the present study was to evaluate the effect that the addition of cholesterol-loaded cyclodextrins (CLC) to the thawing extender has on the quality of frozen-thawed boar sperm. Pooled semen (n = 5) from three boars was used for the experiments. The semen was cryopreserved with an egg-yolk-based extender, it was diluted after thawing in Beltsville thawing solution (BTS) supplemented with different concentrations of CLC (0, 12.5, 25, 50 or 100 mg/500 × 10(6) sperm), and these samples were incubated at 37°C for 150 min. The following parameters of sperm quality were evaluated 30 and 150 min after incubation: sperm with intact plasma membrane (SIPM; %), sperm with normal acrosomal ridge (NAR; %), total motile sperm (TMS; %), progressively motile sperm (PMS; %) and kinetic parameters. Both SIPM and NAR increased (p < 0.05) when the thawing extender was supplemented with 12.5, 25 and 50 mg CLC/500 × 10(6) sperm. Nevertheless, motility decreased (p < 0.05) when the concentration of CLC exceeded 12.5 mg CLC/500 × 10(6) sperm. In conclusion, our results suggest that the supplementation of thawing extenders with CLC improves sperm viability and reduces acrosome damage after freezing/thawing. PMID:24593058

Tomás, C; Gómez-Fernández, J; Gómez-Izquierdo, E; Mocé, E; de Mercado, E

2014-06-01

239

Environmental consequences of increasing production: some current perspectives  

Microsoft Academic Search

Thomas Malthus, in his ‘Essay on Population’ in 1798, argued that food production would not be able to keep pace with our capacity to produce. Contrary to this prediction there seems to be no evidence that our ability to produce food has been a lasting break on population growth. There are, however, several major areas of concern regarding environmental degradation

A. J Bennett

2000-01-01

240

Percutaneous Sperm Retrieval in Secondary Azoospermia  

Microsoft Academic Search

Introduction: Males presenting for assisted reproduction after vasectomy have a high chance of normal spermatogenesis and of successful surgical sperm retrieval. We aimed to evaluate simple percutaneous methods of retrieving sperm for intracytoplasmic sperm injection in males with secondary azoospermia due to previous vasectomy. Patients and Methods: We analyzed a series of post-vasectomy males who presented for sperm retrieval between

S. J. Bromage; D. A. Falconer; B. A. Lieberman; B. Shafar; S. R. Payne

2008-01-01

241

Spermatangium formation and sperm discharge in the Japanese pygmy squid Idiosepius paradoxus.  

PubMed

In cephalopods, sperm discharge is an important event not only for sperm transfer but also influencing sperm storage capacity of attached spermatangia (everted spermatophores). To investigate sperm discharge from spermatangia and the condition of naturally attached spermatangia in Japanese pygmy squid (Idiosepius paradoxus) we (i) investigated the morphology of spermatophores and spermatangia, and the process of spermatophore evagination and sperm discharge from spermatangia obtained in vitro; (ii) observed spermatangia that were naturally attached to female squids at 6, 12, 18, 24 and 48 h after copulation to investigate alterations in naturally attached spermatangia with time. The spermatophore of I. paradoxus is slender and cylindrical and consists of a sperm mass, a cement body and an ejaculatory apparatus, which is similar to those of loliginid squids. The spermatangium is fishhook-shaped, its distal end being open and narrow. After the spermatangium is formed, the sperm mass gradually moves to the open end of the spermatangium, from where sperm are released. Sperm discharge is a rapid process immediately after the beginning of sperm release, but within 5 min changes to an intermittent release of sperm. Although the volume of residual spermatozoa differed among spermatangia that were naturally attached to a single individual, the probability that spermatangia would be empty increased with time. Most naturally attached spermatangia discharged almost all of their spermatozoa within 24h after copulation, and no spermatangia were attached to females 48 h after copulation. These results suggest that sperm transfer from the spermatangium to the seminal receptacle must occur within 24h, and that the spermatangium functions as a transient sperm storage organ in pygmy squids. PMID:24813852

Sato, Noriyosi; Kasugai, Takashi; Munehara, Hiroyuki

2014-06-01

242

Viewing death on television increases the appeal of advertised products.  

PubMed

References to death abound in many television programs accessible to most people. Terror Management Theory postulates that existential anxiety, which death reminders activate, may reinforce materialistic tendencies. The current article explores the effect of a death reminder in television shows on the desirability of advertised products. Consistent with Terror Management Theory's predictions, in two studies participants show greater desire for products, which were advertised immediately following clips from programs that featured a death scene, compared with programs that did not. Cognitive accessibility of death predicted the appeal difference while changes in affect or interest in the show did not. The findings are discussed in light on affective and existential theories which make opposite predictions. Implications and future directions are considered. PMID:22468421

Dar-Nimrod, Ilan

2012-01-01

243

Increased Heterologous Protein Production in Aspergillus niger Fermentation through Extracellular Proteases Inhibition by  

E-print Network

Increased Heterologous Protein Production in Aspergillus niger Fermentation through Extracellular in filamentous fungal fermentation and thereby to enhance heterologous protein production. Introduction with efficient heterologous protein production in the fungal fermentation industry (1, 2). Current strategies

Gu, Tingyue

244

Methamidophos alters sperm function and DNA at different stages of spermatogenesis in mice.  

PubMed

Methamidophos (MET) is a highly toxic organophosphate (OP) pesticide that is widely used in developing countries. MET has male reproductive effects, including decreased fertility. We evaluated MET effects on sperm quality, fertilization and DNA integrity, exploring the sensitivity of different stages of spermatogenesis. Adult male mice received MET (3.75 or 5mg/kg-bw/ip/day/4 days) and were euthanized 1, 28 or 45 days post-treatment (dpt) to evaluate MET's effects on epididymal maturation, meiosis or mitosis, respectively. Spermatozoa were obtained from the cauda epididymis-vas deferens and were evaluated for sperm quality, acrosome reaction (AR; Coomassie staining), mitochondrial membrane potential (by JC-1), DNA damage (comet assay), oxidative damage (malondialdehyde (MDA) production), in vitro fertilization and protein phosphorylation (immunodetection), and erythrocyte acetylcholinesterase (AChE) activity. At 1-dpt, MET inhibited AChE (43-57%) and increased abnormal cells (6%). While at 28- and 45-dpt, sperm motility and viability were significantly reduced with an increasing MET dose, and abnormal morphology increased at 5mg/kg/day/4 days. MDA and mitochondrial activity were not affected at any dose or time. DNA damage (OTM and %DNA) was observed at 5mg/kg/day/4 days in a time-dependent manner, whereas both parameters were altered in cells from mice exposed to 3.75 mg/kg/day/4 days only at 28-dpt. Depending on the time of collection, initial-, spontaneous- and induced-AR were altered at 5mg/kg/day/4 days, and the fertilization capacity also decreased. Sperm phosphorylation (at serine and tyrosine residues) was observed at all time points. Data suggest that meiosis and mitosis are the more sensitive stages of spermatogenesis for MET reproductive toxicity compared to epididymal maturation. PMID:24998973

Urióstegui-Acosta, Mayrut; Hernández-Ochoa, Isabel; Sánchez-Gutiérrez, Manuel; Piña-Guzmán, Belem; Rafael-Vázquez, Leticia; Solís-Heredia, M J; Martínez-Aguilar, Gerardo; Quintanilla-Vega, Betzabet

2014-09-15

245

Chemotactic Motility of Sperm in Shear  

NASA Astrophysics Data System (ADS)

Chemical gradients are utilized by plants and animals in sexual reproduction to guide swimming sperm cells toward the egg. This process (``chemotaxis''), which can greatly increase the success of fertilization, is subject to interference by fluid flow, both in the bodily conduits of internal fertilizers (e.g. mammals) and in the aquatic environment of external fertilizers (e.g. benthic invertebrates). We studied the biomechanics of chemotaxing sea urchin spermatozoa using microfluidic devices, which allow for the precise and independent control of attractant gradients and fluid shear. We captured swimming trajectories and flagellar beat patterns using high-speed video-microscopy, to detect chemotactic responses and measure the effect of fluid forces on swimming. This work will ultimately help us to understand how swimming sperm cells actively navigate natural chemoattractant gradients for successful fertilization.

Guasto, Jeffrey S.; Riffell, Jeffrey A.; Zimmer, Richard K.; Stocker, Roman

2011-11-01

246

Increasing Your Productivity with Web-Based Surveys  

ERIC Educational Resources Information Center

Web-based survey tools such as Survey Monkey can be used in many ways to increase the efficiency and effectiveness of Extension professionals. This article describes how Survey Monkey has been used at the state and county levels to collect community and internal staff information for the purposes of program planning, administration, evaluation and…

Wissmann, Mary; Stone, Brittney; Schuster, Ellen

2012-01-01

247

Increased calf production in cattle selected for twin ovulations  

Technology Transfer Automated Retrieval System (TEKTRAN)

The effects of increasing fetal numbers and their distribution between the left and right uterine horns on calf survival, calf BW at birth and weaning, gestation length, dystocia, and calf sex ratio were evaluated for single (n = 1,587), twin (n = 2,440), and triplet calves (n = 147) born to primipa...

248

Fluid loss control materials increase production at Alba  

SciTech Connect

High-permeability formations are susceptible to formation damage. Drilling or completion fluids can cause permanent damage to the formation and may never be recovered once they leak into formation sand. Downhole processes, such as running in screens and pulling out guns, can also easily lead to damage in an unconsolidated formation. As describes here, Chevron recently used a crosslinkable HEC polymer gel pill and a viscous linear biopolymer prepack fluid to improve drilling and production performance at Alba field in the North Sea.

Ali, S.; McGinn, P.; Fitzpatrick, H.

1996-05-01

249

Researchers from the UA register a biotechnological method that increases production and extraction of phytosterols  

E-print Network

a biotechnological method that allows increasing the production and extraction of phytosterols in the growth of plant growth process of plant cells in vitro, it is possible to increase the production and the performanceResearchers from the UA register a biotechnological method that increases production and extraction

Escolano, Francisco

250

Sea urchin sperm antigens mediating the acrosome reaction  

SciTech Connect

The study of sea urchin sperm antigens mediating the acrosome reactions (AR) has been undertaken. Monoclonal antibodies (mAbs) have been isolated reacting with a number of sperm surface antigens. These mAbs have been used in functional assays to attempt to infer the roles of these proteins in the induction of the AR. These mAbs have also been used to isolate protein for biochemical characterization and reconstitution studies. mAbs reacting with a 210 kD protein of the sea urchin sperm plasma membrane have been used to identify this protein as playing a role in the regulation of ion fluxes during the induction of the AR. mAbs reacting with certain extracellular regions inhibit the induction of: the AR, the long duration {sup 45}Ca{sup 2+} uptake into the mitochondrion, and H{sup +} efflux. Addition of these same mAbs, however, induces an increase in sperm (Ca{sup 2+}){sub i} to levels much higher than those induced by FSG, as monitored by the fluorescent Ca{sup 2+} indicators fura 2 and indo 1. This (Ca{sup 2+}){sub i} increase occurs without an increase in pH{sub i}, and thus allows for the first time the analysis of the effects of increasing sperm (Ca{sup 2+}){sub i} ion the absence of increased pH{sub i}.

Trimmer, J.S.

1987-01-01

251

Semen characterization, seasonality of production, and in vitro sperm quality after chilled storage and cryopreservation in the king penguin (Aptenodytes patagonicus).  

PubMed

Research was conducted to examine seasonal seminal traits and to establish short-term and long-term sperm preservation methods in the king penguin (Aptenodytes patagonicus) for use in genome banking and artificial insemination (AI). Spermic ejaculates (n?=?87) obtained using a cooperative method were collected across multiple (n?=?6, Male 1) and a single (Male 2) breeding season(s). Non-contaminated ejaculates (n?=?69) were 0.36?±?0.32?ml at 56.3?±?62.7?×?10(7) ?sperm/ml with 85.3?±?10.6% total motility (TMot), 52.5?±?12.9% progressive motility (PMot), 86.6?±?24.3?µm/sec average path velocity (VAP) and 92.3?±?3.7% plasma membrane intact. In vitro quality of chilled semen was best maintained over 48?hr at 5°C than 21°C, with decreased (P?

O'Brien, Justine K; Robeck, Todd R

2014-01-01

252

Cinnamic Acid Increases Lignin Production and Inhibits Soybean Root Growth  

PubMed Central

Cinnamic acid is a known allelochemical that affects seed germination and plant root growth and therefore influences several metabolic processes. In the present work, we evaluated its effects on growth, indole-3-acetic acid (IAA) oxidase and cinnamate 4-hydroxylase (C4H) activities and lignin monomer composition in soybean (Glycine max) roots. The results revealed that exogenously applied cinnamic acid inhibited root growth and increased IAA oxidase and C4H activities. The allelochemical increased the total lignin content, thus altering the sum and ratios of the p-hydroxyphenyl (H), guaiacyl (G), and syringyl (S) lignin monomers. When applied alone or with cinnamic acid, piperonylic acid (PIP, a quasi-irreversible inhibitor of C4H) reduced C4H activity, lignin and the H, G, S monomer content compared to the cinnamic acid treatment. Taken together, these results indicate that exogenously applied cinnamic acid can be channeled into the phenylpropanoid pathway via the C4H reaction, resulting in an increase in H lignin. In conjunction with enhanced IAA oxidase activity, these metabolic responses lead to the stiffening of the cell wall and are followed by a reduction in soybean root growth. PMID:23922685

Salvador, Victor Hugo; Lima, Rogério Barbosa; dos Santos, Wanderley Dantas; Soares, Anderson Ricardo; Böhm, Paulo Alfredo Feitoza; Marchiosi, Rogério; Ferrarese, Maria de Lourdes Lucio; Ferrarese-Filho, Osvaldo

2013-01-01

253

Effect of aracnotoxin from Latrodectus mactans on bovine sperm function: modulatory action of bovine oviduct cells and their secretions.  

PubMed

Latrodectus mactans' aracnotoxin (Atx) induces changes in sperm function that could be used as a co-adjuvant in male contraceptive barrier methods. This effect includes the suppression of intracellular reactive oxygen species (ROS), an event necessary for capacitation, chemotaxis and acrosome reaction (AR). The sperm that are not trapped by the barrier method can reach the oviduct before fertilisation and be exposed to the secretions of the oviducts. This study evaluated the effect of bovine tubal explants (TU) and conditioned media (CM) from the ampullar and isthmal regions on spermatozoa exposed to Atx. Thawed bovine sperm were incubated with Atx, TU and CM from the ampullar and isthmal regions for 4 h and then DNA integrity, intracellular ROS and lysophosphatidylcholine-induced AR were determined. Spermatozoa exposed to Atx and co-incubated with TU and CM for 4 h produced an increase in sperm DNA damage, a decrease in ROS production and a decrease in %AR, compared with the control. A similar result was obtained from the co-incubation of spermatozoa with Atx. In conclusion, the effect of Atx is not modified by tubal cells or their secretions and this opens the door to future studies to evaluate the application of synthetic peptides obtained from Atx as a co-adjuvant of contraceptive barrier methods. PMID:22211875

Gómez, P N; Alvarez, J G; Parodi, J; Romero, F; Sánchez, R

2012-05-01

254

Writing Retreat Increases Productivity And Community For Women Geoscientists  

NASA Astrophysics Data System (ADS)

Five, weeklong geoscientist writing retreats have been completed with an NSF ADANCE PAID grant. During the five nights and four and a half days, eight to twenty-four academics have gathered in a rural setting outside of Boston to get to focus on writing papers and proposals while getting to know each other. Participants range in age and experience from graduate students to emeritus professors. Over twenty papers and proposals acknowledge their production, in part to this writing retreat. Impact extends beyond papers as informal mentoring and discussions at meals and in the evenings centers on succeeding in academia. Research and teaching are foremost in the conversation. Post-docs learn strategies for applying for jobs and grants, and senior professors discuss strategies for working with academic administrations, running departments and mentoring students. They also learn new technologies and perspectives from younger participants. Particularly helpful are discussions on work-life balance. Networking opportunities extend beyond the retreat as participants join each other at their home institutions to give seminars, develop research projects and mentor each other's students. All weeks follow the same format. Participants arrive Sunday and meet during an evening welcome reception. Monday is devoted to writing. Tuesday a writing coach is available. In the morning, using examples from the scientific literature, she discusses strategies and techniques for writing clearly at a group session. During the afternoon, participants work with the coach individually or in small groups to improve their own writing projects. Wednesday evening a skill session is offered on a topic of interest. These have included undergraduate research, NSF funding, productive techniques for dealing with conflict, and generational characteristics and attitudes, which can hamper communication. A Thursday evening wrap-up session prepares participants for Friday's departure. We believe that this model is replicable to other regions or to single institutions. All that is really required is space, meals, and a writing coach or a journal editor. Costs are very reasonable, considering the positive lifelong impact on this most necessary skill for the productive scientist.

O'Connell, S.; Holmes, M.

2011-12-01

255

Science Video Journals to Increase Productivity in Research and Education  

NASA Astrophysics Data System (ADS)

Research in both the physical and biological sciences chronically suffers from the low productivity and reproducibility of experimental studies. This is due in part because the traditional text-based format of science journals cannot provide an adequate description of complex research procedures. This creates a critical 'bottleneck' problem of knowledge transfer for research and education. Addressing this challenge, a new generation of science journals employs online video to provide a systematic visualized publication of experimental studies. This presentation will provide an overview of the growing field of video publication and discuss its technical challenges, implications for scholarly communication and acceptance in the academic and library community. Results and recently conducted case studies will be shown in support of video publications as a valid communication venue in scientific publishing.

Henderson, K. M.

2013-12-01

256

Pronounced within-individual plasticity in sperm morphometry across social environments.  

PubMed

Sperm morphometry (i.e., size and shape) and function are important determinants of male reproductive success and are thought to be under stabilizing selection. However, recent studies suggest that sperm morphometry can be a phenotypically plastic trait, which can be adjusted to varying conditions. We tested whether different behavioral strategies in aggression between aggressive red and nonaggressive black males of the color polymorphic Gouldian finch (Erythrura gouldiae) can influence sperm morphometry. We show pronounced within-individual phenotypic plasticity in sperm morphometry of male Gouldian finches in three different social environments. Both red and black males placed in intermediate to high competitive environments (high frequency of red males) increased the relative length of their sperm midpiece. By contrast, red males placed in low to intermediate competitive environments (higher frequency of black males) increased the length of the sperm flagellum. Significant changes in stress and sex steroid hormone levels (in response to the competitive environment) appear to influence sperm traits in red but not in black males, suggesting that changes in hormonal levels are not solely responsible for the observed changes in sperm morphometry. These findings imply that males can adjust sperm morphometry across social environments. PMID:20015235

Immler, Simone; Pryke, Sarah R; Birkhead, Tim R; Griffith, Simon C

2010-06-01

257

Oligodeoxyribonucleotides derived from salmon sperm DNA: an alternative to defibrotide.  

PubMed

Defibrotide is a single-stranded nucleic acid polymer originally derived from porcine mucosa. Cheap salmon sperm DNA is commercially available and widely used in drug production. In this study, oligodeoxyribonucleotides were successfully obtained from the controlled depolymerization of salmon sperm DNA. The obtained product shared similar chemical and biological properties with defibrotide produced by Gentium SpA, Italy. It was also found that oligodeoxyribonucleotides derived from non-mammalian origins could also directly stimulate tissue plasminogen activator (t-PA) release from cultured human endothelial cells, and enhance fibrinolytic activity in the rabbit. PMID:23375586

Hui, Chang-Ye; Guo, Yan; Zhang, Xi; Shao, Jian-Hua; Yang, Xue-Qin; Zhang, Wen

2013-05-01

258

Intracytoplasmic sperm injection: a novel selection method for sperm with normal frequency of chromosomal aneuploidies  

Microsoft Academic Search

Objective: To test a newly invented intracytoplasmic sperm injection (ICSI) sperm selection method based on sperm hyaluronic acid (HA) binding. Design: Comparison of chromosomal disomy and diploidy frequencies in sperm arising from semen and in HA-bound sperm. Setting: Academic andrology laboratory. Patient(s): Men presenting for semen analysis. Intervention(s): Washed sperm fractions of 32 semen samples were applied to Petri dishes

Attila Jakab; Denny Sakkas; Elena Delpiano; Sevil Cayli; Ertug Kovanci; David Ward; Alberto Ravelli; Gabor Huszar

2005-01-01

259

Mutant E. coli strain with increased succinic acid production  

DOEpatents

A method for isolating succinic acid producing bacteria is provided comprising increasing the biomass of an organism which lacks the ability to catabolize pyruvate, and then subjecting the biomass to glucose-rich medium in an anaerobic environment to enable pyruvate-catabolizing mutants to grow. The invention also provides for a mutant that produces high amounts of succinic acid, which as been derived from a parent which lacked the genes for pyruvate formate lyase and lactate dehydrogenase, and which belongs to the E.coli Group of Bacteria.

Donnelly, Mark (Warrenville, IL); Millard, Cynthia S. (Plainfield, IL); Stols, Lucy (Woodridge, IL)

1998-01-01

260

Mutant E. coli strain with increased succinic acid production  

DOEpatents

A method for isolating succinic acid producing bacteria is provided comprising increasing the biomass of an organism which lacks the ability to catabolize pyruvate, and then subjecting the biomass to glucose-rich medium in an anaerobic environment to enable pyruvate-catabolizing mutants to grow. The invention also provides for a mutant that produces high amounts of succinic acid, which has been derived from a parent which lacked the genes for pyruvate formate lyase and lactate dehydrogenase, and which belongs to the E.coli Group of Bacteria.

Donnelly, Mark (Warrenville, IL); Millard, Cynthia S. (Plainfield, IL); Stols, Lucy (Woodridge, IL)

2002-01-01

261

Sperm competition and the evolution of male reproductive anatomy in rodents  

PubMed Central

Sperm competition is a pervasive selective force in evolution, shaping reproductive anatomy, physiology and behaviour. Here, we present comparative evidence that varying sperm competition levels account for variation in the male reproductive anatomy of rodents, the largest and most diverse mammalian order. We focus on the sperm-producing testes and the accessory reproductive glands, which produce the seminal fluid fraction of the ejaculate. We demonstrate a positive association between relative testis size and the prevalence of within-litter multiple paternity, consistent with previous analyses in which relative testis size has been found to correlate with sperm competition levels inferred from social organization and mating systems. We further demonstrate an association between sperm competition level and the relative size of at least two accessory reproductive glands: the seminal vesicles and anterior prostate. The size of the major product of these glands—the copulatory plug—is also found to vary with sperm competition level. Our findings thus suggest that selection for larger plugs under sperm competition may explain variation in accessory gland size, and highlight the need to consider both sperm and non-sperm components of the male ejaculate in the context of post-copulatory sexual selection. PMID:16024351

Ramm, Steven A; Parker, Geoffrey A; Stockley, Paula

2005-01-01

262

Heat Shock Protein 90 Has Roles in Intracellular Calcium Homeostasis, Protein Tyrosine Phosphorylation Regulation, and Progesterone-Responsive Sperm Function in Human Sperm  

PubMed Central

Heat shock protein 90 plays critical roles in client protein maturation, signal transduction, protein folding and degradation, and morphological evolution; however, its function in human sperm is not fully understood. Therefore, our objective in this study was to elucidate the mechanism by which heat shock protein 90 exerts its effects on human sperm function. By performing indirect immunofluorescence staining, we found that heat shock protein 90 was localized primarily in the neck, midpiece, and tail regions of human sperm, and that its expression increased with increasing incubation time under capacitation conditions. Geldanamycin, a specific inhibitor of heat shock protein 90, was shown to inhibit this increase in heat shock protein 90 expression in western blotting analyses. Using a multifunctional microplate reader to examine Fluo-3 AM-loaded sperm, we observed for the first time that inhibition of heat shock protein 90 by using geldanamycin significantly decreased intracellular calcium concentrations during capacitation. Moreover, western blot analysis showed that geldanamycin enhanced tyrosine phosphorylation of several proteins, including heat shock protein 90, in a dose-dependent manner. The effects of geldanamycin on human sperm function in the absence or presence of progesterone was evaluated by performing chlortetracycline staining and by using a computer-assisted sperm analyzer. We found that geldanamycin alone did not affect sperm capacitation, hyperactivation, and motility, but did so in the presence of progesterone. Taken together, these data suggest that heat shock protein 90, which increases in expression in human sperm during capacitation, has roles in intracellular calcium homeostasis, protein tyrosine phosphorylation regulation, and progesterone-stimulated sperm function. In this study, we provide new insights into the roles of heat shock protein 90 in sperm function. PMID:25541943

Chen, Aijun; Jiang, Youfang; Xie, Haifeng; Shi, Qixian; Zhang, Songying; Ni, Ya

2014-01-01

263

The relationship between paternal age, sex ratios, and aneuploidy frequencies in human sperm, as assessed by multicolor FISH  

SciTech Connect

We studied the frequencies of X- and Y-chromosome bearing sperm, diploidy and disomy for chromosomes 1, 12, X, and Y in sperm from 10 normal men aged 21 - 52 years, to determine whether there was any relationship between donor age and any of these variables. Multicolor FISH was used to control for lack of probe hybridization and to distinguish diploid sperm from disomic sperm. A minimum of 10,000 sperm per donor was evaluated for each chromosome, for a total of 225,846 sperm studied. Sperm were considered disomic if two fluorescent signals were separated by a minimal distance of one signal domain. The mean frequencies of X- and Y-bearing sperm were 50.1% and 49.0%, respectively; not significantly different from 50%. There was no correlation between paternal age and {open_quotes}sex ratio {close_quotes} in sperm. Similarly, there was no association between the frequency of diploid sperm (mean, .16%; range, .06%-.42%) and donor age. For disomy frequencies, there was no relationship between donor age and disomy 12 (mean, .16%; range, .10%-.25%), XX (mean, .07%; range, .03%-.17%), and XY sperm (mean, .16%; range, .08%-.24%). There was a significant increase in the frequency of YY sperm (P = .04; mean, .18%; range, .10%-.43%) and disomy 1 sperm (P = .01; mean, .11%; range, .05%-.18%) with donor age. In summary, our results do not support a correlation between paternal age and sex ratio or diploidy. A relationship between paternal age and disomy was observed for disomy 1 and YY sperm but not for disomy 12, XX or XY sperm. 37 refs., 3 tabs.

Martin, R.H.; Spriggs, E. [Univ. of Calgary, Alberta (Canada)]|[Alberta Children`s Hospital, Calgary, Alberta (Canada); Ko, E. [Alberta Children`s Hospital, Calgary, Alberta (Canada)] [and others

1995-12-01

264

Assessment of chromosomal abnormalities in sperm of infertile men using sperm karyotyping and multicolour fluorescence in situ hybridization (FISH)  

SciTech Connect

Individuals with male factor infertility resulting from idiopathic oligo-, astheno- or teratozoospermia are frequently offered IVF in an attempt to increase their chances of having a child. A concern remains whether these infertile males have an elevated risk of transmitting chromosomal abnormalities to their offspring. Sperm chromosomal complements from these men were assayed using the human sperm/hamster oocyte fusion system and fluorescence in situ hybridization (FISH) on sperm nuclei. For each of 5 infertile patients, 100 sperm karyotypes were analyzed and multicolour FISH analysis was performed on a minimum of 10,000 sperm nuclei for each chromosome-specific DNA probe for chromosomes 1 (pUC1.77), 12 (D12Z3), X (XC) and Y (DYZ3). As a group, the infertile patients showed increased frequencies of both numerical ({chi}{sup 2}=17.26, {proportional_to} <0.001) and total abnormalities ({chi}{sup 2}=7.78, {proportional_to} <0.01) relative to control donors when assessed by sperm karyotypes. Analysis of sperm nuclei by FISH indicated a significant increase in the frequency of disomy for chromosome 1 in three of the five patients as compared to control donors ({chi}{sup 2}>8.35, {proportional_to} <0.005). In addition, the frequency of XY disomy was significantly higher in four of the five patients studied by FISH ({chi}{sup 2}>10.58, {proportional_to}<0.005), suggesting that mis-segregation caused by the failure of the XY bivalent to pair may play a role in idiopathic male infertility.

Moosani, N.; Martin, R.H. [Alberta Children`s Hospital and Univ. of Calgary (Canada)

1994-09-01

265

Surgical sperm retrieval: Techniques and their indications  

PubMed Central

Men with azoospermia can father a child through intra-cytoplasmic sperm injection if sperm can be retrieved from their epididymis or testis. Several percutaneous and open surgical procedures have been described to retrieve sperm. The various techniques and their merits are discussed in this review. In men with obstructive azoospermia, epididymal sperm can usually be retrieved by percutaneous epididymal sperm aspiration (PESA). If PESA fails then testicular sperm are obtained by needle aspiration biopsy (NAB). In men with non-obstructive azoospermia, there will be no sperm in the epididymis and testicular sperm retrieval is required. Percutaneous retrieval by NAB can be tried first. If that fails then testicular sperm extraction (TESE) from open microsurgical biopsies is performed using the single seminiferous tubule (SST) or the microdissection TESE techniques. The simplest, least invasive procedure should be tried first. PMID:21716933

Shah, Rupin

2011-01-01

266

Generation of Live Piglets for the First Time Using Sperm Retrieved from Immature Testicular Tissue Cryopreserved and Grafted into Nude Mice  

PubMed Central

Cryopreservation of immature testicular tissues is essential for increasing the possibilities of offspring generation by testicular xenografting for agricultural or medical purposes. However, successful production of offspring from the sperm involved has never been reported previously. In the present study, therefore, using intracytoplasmic sperm injection (ICSI), we examined whether xenogeneic sperm obtained from immature pig testicular tissue after cryopreservation would have the capacity to produce live piglets. Testicular fragments from 9- to 11-day-old piglets were vitrified after 10- or 20-min immersion in vitrification solution containing ethylene glycol (EG), polyvinyl pyrrolidone (PVP) and trehalose as cryoprotectants, and then stored in liquid nitrogen for more than 140 days. Thirty nude mice were assigned to each immersion-time group. Testicular fragments were transplanted under the back skin of castrated mice immediately after warming and removal of the cryoprotectants. Blood and testicular grafts were then recovered from the recipient mice on days 60, 120, 180 and 230?350 (day 0?=? grafting). Histological assessment of the testicular grafts and analyses of inhibin and testosterone production revealed no significant differences between the two immersion-time groups, indicating equal growth activity of the cryopreserved tissues. A single sperm obtained from a mouse in each group on day 230?350 was injected into an in vitro-matured porcine oocyte, and then the ICSI oocytes were transferred to the oviducts of estrus-synchronized recipient gilts. One out of 4 gilts that had received oocytes fertilized using sperm from the 10-min immersion group delivered 2 live piglets, and one of another 4 gilts from the 20-min group delivered 4 live piglets. Thus, we have successfully generated porcine offspring utilizing sperm from immature testicular tissues after cryopreservation and transplantation into nude mice. The present model using pigs will be applicable to many large animals, since pigs are phylogenetically distant from the murine recipients. PMID:23923039

Nakai, Michiko; Somfai, Tamas; Noguchi, Junko; Tanihara, Fuminori; Ito, Junya; Kashiwazaki, Naomi

2013-01-01

267

Morphological diversity of sperm: A mini review  

PubMed Central

Sperms are highly specialized cells for delivering DNA from male to the ovum. Incredibly, wide degree of diversity in sperm morphology in their basic structures i.e. head, middle piece and tail is found across species. Differences in terms of overall size of the sperm, shape and number of sperm produced are also incredible. One of the key for this variations or diversity in sperm may be associated with female reproductive tract, sperm competition, testicular size and sperm size and number. Establishing a correlation between sperm morphology and factors influencing them is a phenomenal task. In this mini-review these associations and the anatomical and functional adaptations among different from of sperm cells that have evolved to optimize fertilization success are discussed. Nevertheless, explaining these morphological diversities in sperm cells is a challenging question and it seems that evolutionary biologists have only recently engaged in exploring its links and patterns. From the literatures it seems that there is no causal relationship between sperm size and testicular size, however, the accumulated knowledge do indicates evolution of sperm morphology across species has some associations with female reproductive tract, sperm competition and sperm size and number, however interpreting these results for phylogentic correlations should be approached with caution. PMID:24976817

Prakash, Seppan; Prithiviraj, Elumalai; Suresh, Sekar; Lakshmi, Nagella Venkata; Ganesh, Mohanraj Karthik; Anuradha, Murugesan; Ganesh, Lakshmanan; Dinesh, Premavathy

2014-01-01

268

Sperm Bundles in the Seminal Vesicles of Sexually Mature Lasius Ant Males  

PubMed Central

In many insects, sperm cells are produced in bundles with their heads being held together by a glycoprotein matrix secreted by a cyst cell. Mature sperm cells in the seminal vesicles are usually free, but in sawflies and several other insects, such structures (spermatodesmata) remain intact and sperm cells may be ejaculated as bundles. Here we report the occurrence of spermatodesmata in mature males of the ant Lasius pallitarsis. Microscopic investigations of the abdominal contents of males immediately prior to their nuptial flights showed that the anterior ends of numerous sperm cells were embedded in an oval-shaped 20 by 30 micrometer extracellular fibrous cap. Individual sperm ranged in length from 55 to 75 micrometers with an average overall length of 65 micrometers. The bulb-shaped heads of the sperm were relatively small, only about 1.5 micrometers in length and about 1.1 micrometers in diameter. The diameter of the sperm tails was approximately 1 micrometer. Observations of live preparations of the spermatodesmata showed increasingly active undulating wave-like movement of the sperm tails as the slide preparations aged. This appears to be the first case of sperm bundles being present in the seminal vesicles of mature ant males – males that are immediately poised to complete their nuptial mating flight. PMID:24671307

Burnett, William E.; Heinze, Jürgen

2014-01-01

269

Sperm Swimming Velocity Predicts Competitive Fertilization Success in the Green Swordtail Xiphophorus helleri  

PubMed Central

Sperm competition is expected to favour the evolution of traits that influence the performance of sperm when they compete to fertilize a female's eggs. While there is considerable evidence that selection favours increases in sperm numbers, much less is known about how sperm quality contributes towards competitive fertilization success. Here, we determine whether variation in sperm quality influences competitive fertilization success in the green swordtail Xiphophorus helleri, a highly promiscuous livebearing fish. We use artificial insemination as a method of controlled sperm delivery and show that sperm swimming velocity is the primary determinant of fertilization success when ejaculates from two males compete to fertilize a female's eggs. By contrast, we found no evidence that sperm length had any effect on siring success. We also found no evidence that pre- and postcopulatory sexual traits were phenotypically integrated in this species, suggesting that the previous observation that reproductive skew favours males with high mating rates is unlikely to be due to any direct association between sperm quality and male sexual ornamentation. PMID:20730092

Gasparini, Clelia; Simmons, Leigh W.; Beveridge, Maxine; Evans, Jonathan P.

2010-01-01

270

Sperm chromatin structure assay (SCSA): a tool in diagnosis and treatment of infertility.  

PubMed

Diagnosis of male infertility has mainly been based on the World Health Organization (WHO) manual-based semen parameter's concentration, motility and morphology. It has, however, become apparent that none of these parameters are reliable markers for evaluation of the fertility potential of a couple. A search for better markers has led to an increased focus on sperm chromatin integrity testing in fertility work-up and assisted reproductive techniques. During the last couple of decades, numerous sperm DNA integrity tests have been developed. These are claimed to be characterized by a lower intraindividual variation, less intralaboratory and interlaboratory variation and thus less subjective than the conventional sperm analysis. However, not all the sperm chromatin integrity tests have yet been shown to be of clinical value. So far, the test that has been found to have the most stable clinical threshold values in relation to fertility is the sperm chromatin structure assay (SCSA), a flow cytometric test that measures the susceptibility of sperm DNA to acid-induced DNA denaturation in situ. Sperm DNA fragmentation as measured by SCSA has shown to be an independent predictor of successful pregnancy in first pregnancy planners as well as in couples undergoing intrauterine insemination, and can be used as a tool in investigation, counseling and treatment of involuntary childlessness. More conflicting data exist regarding the role of sperm DNA fragmentation in relation to fertilization, pre-embryo development and pregnancy outcome in in vitro fertilization and intracytoplasmic sperm injection (ICSI). PMID:21057512

Bungum, Mona; Bungum, Leif; Giwercman, Aleksander

2011-01-01

271

Sperm chromatin structure assay (SCSA): a tool in diagnosis and treatment of infertility  

PubMed Central

Diagnosis of male infertility has mainly been based on the World Health Organization (WHO) manual-based semen parameter's concentration, motility and morphology. It has, however, become apparent that none of these parameters are reliable markers for evaluation of the fertility potential of a couple. A search for better markers has led to an increased focus on sperm chromatin integrity testing in fertility work-up and assisted reproductive techniques. During the last couple of decades, numerous sperm DNA integrity tests have been developed. These are claimed to be characterized by a lower intraindividual variation, less intralaboratory and interlaboratory variation and thus less subjective than the conventional sperm analysis. However, not all the sperm chromatin integrity tests have yet been shown to be of clinical value. So far, the test that has been found to have the most stable clinical threshold values in relation to fertility is the sperm chromatin structure assay (SCSA), a flow cytometric test that measures the susceptibility of sperm DNA to acid-induced DNA denaturation in situ. Sperm DNA fragmentation as measured by SCSA has shown to be an independent predictor of successful pregnancy in first pregnancy planners as well as in couples undergoing intrauterine insemination, and can be used as a tool in investigation, counseling and treatment of involuntary childlessness. More conflicting data exist regarding the role of sperm DNA fragmentation in relation to fertilization, pre-embryo development and pregnancy outcome in in vitro fertilization and intracytoplasmic sperm injection (ICSI). PMID:21057512

Bungum, Mona; Bungum, Leif; Giwercman, Aleksander

2011-01-01

272

Mating systems and protein–protein interactions determine evolutionary rates of primate sperm proteins  

PubMed Central

To assess the relative impact of functional constraint and post-mating sexual selection on sequence evolution of reproductive proteins, we examined 169 primate sperm proteins. In order to recognize potential genome-wide trends, we additionally analysed a sample of altogether 318 non-reproductive (brain and postsynaptic) proteins. Based on cDNAs of eight primate species (Anthropoidea), we observed that pre-mating sperm proteins engaged in sperm composition and assembly show significantly lower incidence of site-specific positive selection and overall lower non-synonymous to synonymous substitution rates (dN/dS) across sites as compared with post-mating sperm proteins involved in capacitation, hyperactivation, acrosome reaction and fertilization. Moreover, database screening revealed overall more intracellular protein interaction partners in pre-mating than in post-mating sperm proteins. Finally, post-mating sperm proteins evolved at significantly higher evolutionary rates than pre-mating sperm and non-reproductive proteins on the branches to multi-male breeding species, while no such increase was observed on the branches to unimale and monogamous species. We conclude that less protein–protein interactions of post-mating sperm proteins account for lowered functional constraint, allowing for stronger impact of post-mating sexual selection, while the opposite holds true for pre-mating sperm proteins. This pattern is particularly strong in multi-male breeding species showing high female promiscuity. PMID:24307672

Schumacher, Julia; Rosenkranz, David; Herlyn, Holger

2014-01-01

273

No Experimental Evidence for Sneaking in a West African Cichlid Fish with Extremely Long Sperm  

PubMed Central

Alternative reproductive tactics are widespread in fishes, increasing the potential for sperm competition. Sperm competition has enormous impact on both variation in sperm numbers and sperm size. In cichlids, the sperm competition risk is very divergent and longer sperm are usually interpreted as adaptation to sperm competition. Here we examined whether sneaking tactics exist in Pelvicachromis taeniatus, a socially monogamous cichlid with biparental brood care from West Africa. The small testis indicates low gonadal investment which is typical for genetically monogamous species. In contrast, sperm length with up to 85??m is extraordinarily long. We examined the reproductive behaviour of ten groups with a male-biased sex ratio under semi-natural conditions via continuous video recording. We recorded spawning site preferences and correlates of reproductive success and conducted paternity tests using microsatellites. Safe breeding sites that could be successfully defended were preferred. All offspring could be assigned to their parents and no multiple paternities were detected. Body size of spawning pairs predicted their spawning probability and offspring hatching rate suggesting benefits from mating with large individuals. Our study suggests low risk of sperm competition under the given conditions in P. taeniatus and thus first evidence for genetic monogamy in a substrate breeding cichlid. PMID:24386589

Langen, Kathrin; Thünken, Timo; Bakker, Theo C. M.

2013-01-01

274

Sperm cleanup and centrifugation processing for cryopreservation.  

PubMed

Fertility rates with artificial insemination are highest with good-quality sperm samples. Therefore, nonviable sperm, cellular debris, and seminal plasma are preferably removed from semen samples prior to use or for preservation. Such compounds are sources where reactive oxygen species are generated during storage or upon cryopreservation, impairing sperm function. In this chapter we describe methods to remove seminal plasma and cellular debris from sperm samples, and for selecting morphologically normal motile sperm. The methods that are described here include: ordinary centrifugation, sperm swim-up, glass wool and Sephadex filtration/adherence, and single-layer as well as discontinuous two-layer iodixanol density gradient centrifugation. PMID:25428016

Sieme, Harald; Oldenhof, Harriëtte

2015-01-01

275

The spectrum of DNA damage in human sperm assessed by single cell gel electrophoresis (Comet assay) and its relationship to fertilization and embryo development  

Microsoft Academic Search

BACKGROUND: The integrity of sperm DNA is important for the success of natural or assisted fertilization, as well as normal development of the embryo, fetus and child. ICSI, by bypassing sperm selection mechanisms, increases the risk of transmitting damaged DNA and the significance of this requires investigation. METHODS: DNA damage in sperm from an unselected group of 60 men undergoing

I. D. Morris; S. Ilott; L. Dixon; D. R. Brison

2002-01-01

276

Production System Techniques to Increase Nitrogen Use Efficiency in Winter Wheat  

Microsoft Academic Search

Most current research on winter wheat (Triticum aestivum L.) focuses on increasing yields of either grain or plant biomass. Increased production costs and environmental awareness will promote the development of methods to increase the efficiency of applied nutrients. Nitrogen (N) is often the most limiting nutrient for cereal grain production and represents one of the highest input costs in agricultural

W. E. Thomason; W. R. Raun; G. V. Johnson; K. W. Freeman; K. J. Wynn; R. W. Mullen

2002-01-01

277

Clinical relevance of sperm DNA damage in assisted reproduction.  

PubMed

Many studies have shown how a 'paternal effect' can cause repeated assisted reproduction failures. In particular, with increasing experience of intracytoplasmic sperm injection (ICSI), it became evident that spermatozoa from some patients repeatedly fail to form viable embryos, although they can fertilize the oocyte and trigger early preimplantation development. Many authors have shown how this paternal effect can be traced back to anomalies in sperm chromatin organization: the spermatozoa of subfertile men are characterized by numerical abnormalities in spermatozoal chromosome content, Y chromosome microdeletions, alterations in the epigenetic regulation of paternal genome and non-specific DNA strand breaks. In particular, pathologically increased sperm DNA fragmentation is one of the main paternal-derived causes of repeated assisted reproduction failures in the ICSI era. The intention of this review is to describe nuclear sperm DNA damage, with emphasis on its clinical significance and its relationship with male infertility. Assessment of sperm DNA damage appears to be a potential tool for evaluating semen samples prior to their use in assisted reproduction, helping to select spermatozoa with intact DNA or with the least amount of DNA damage for use in assisted conception. PMID:17579991

Tarozzi, Nicoletta; Bizzaro, Davide; Flamigni, Carlo; Borini, Andrea

2007-06-01

278

Sperm competition and the evolution of seminal fluid composition.  

PubMed

Male ejaculates include large amounts of seminal fluid proteins (Sfps) that influence male sperm competitive success. In spite of their diverse proximate functions, Sfps involved in sperm competition increase male fitness in one of three ways: (1) "avoidance" proteins help males avoid sperm competition, (2) "defense" proteins help males defend their sperm from displacement by the female's subsequent mate, and (3) "offense" proteins aid males in displacing sperm of preceding males. Here, we present a population genetic model of the evolution of allocation of finite resources by males to the three kinds of Sfps. We analyze the influence of relative efficiencies of different Sfps, of plasticity in resource allocation, and of differences in viability costs of Sfps. We find that in absence of plasticity or different viability costs, equal investment in defense and offense Sfps evolves, irrespective of their relative efficiency. In all cases, males evolve to invest more in avoidance when avoidance proteins are increasingly efficient, and when offense is more efficient than defense. Differences in viability costs result in lower investment in costly proteins, whereas plasticity has complex effects, influencing both the optimal seminal fluid composition and maintenance of variation in investment in these proteins across populations. PMID:24975874

Dhole, Sumit; Servedio, Maria R

2014-10-01

279

Environmental toxicants cause sperm DNA fragmentation as detected by the Sperm Chromatin Structure Assay (SCSA[reg])  

SciTech Connect

Studies over the past two decades have clearly shown that reproductive toxicants cause sperm DNA fragmentation. This DNA fragmentation can usually be detected prior to observing alterations of metaphase chromosomes in embryos. Thus, Sperm Chromatin Structure Assay (SCSA)-detected DNA damage is viewed as the molecular precursor to later gross chromosome damage observed under the light microscope. SCSA measurements of animal or human sperm consist of first obtaining a fresh or flash frozen neat semen sample in LN2 or dry ice. Samples are then sent to a SCSA diagnostic laboratory where the samples are thawed, diluted to {approx}1-2 x 106 sperm/ml, treated for 30 s with a pH 1.2 detergent buffer and then stained with acridine orange (AO). The low pH partially denatures DNA at the sites of DNA strand breaks and the AO-ssDNA fluoresces red while the AO-dsDNA fluoresces green. Flow cytometry measurements of 5000 sperm/sample provide statistically robust data on the ratio of red to green sperm, the extent of the DNA fragmentation and the standard deviations of measures. Numerous experiments on rodents treated with reproductive toxicants clearly showed that SCSA measures are highly dose responsive and have a very low CV. Different agents that act on germ cells at various stages of development usually showed sperm DNA fragmentation when that germ cell fraction arrived in the epididymis or ejaculate. Some of these treated samples were capable of successful in vitro fertilization but with frequent embryo failure. A 2-year longitudinal study of men living a valley town with a reported abnormal level of infertility and spontaneous miscarriages and also a seasonal atmospheric smog pollution, showed, for the first time, that SCSA measurements of human sperm DNA fragmentation were detectable and correlated with dosage of air pollution while the classical semen measures were not correlated. Also, young men spraying pesticides without protective gear are at an increased risk for elevated sperm DNA fragmentation. Extensive DNA fragmentation probably cannot be repaired by the egg and the spontaneous abortion rate is {approx}2x higher if a man has more than 30% of sperm showing DNA fragmentation. DNA fragmentation is an excellent marker for exposure to potential reproductive toxicants and a diagnostic/prognostic tool for potential male infertility.

Evenson, Donald P. [HCLD, Department of Chemistry and Biochemistry, South Dakota State University, Brookings, SD 57007 (United States) and SCSA Diagnostics, 807 32nd Avenue, Brookings, SD 57007 (United States)]. E-mail: scsa@brookings.net; Wixon, Regina [SCSA Diagnostics, 807 32nd Avenue, Brookings, SD 57007 (United States)

2005-09-01

280

Effect of proctodeal gland foam on sperm kinetics in Japanese quail (Coturnix japonica).  

PubMed

The proctodeal gland of the male Japanese quail produces thick foam that accompanies semen when it is transferred to the female. It is thought that this foam enhances fertilization by improving the motility of the sperm, but reports are conflicting because the effect of foam on sperm motility has only been assessed subjectively The velocity of individual sperm was not able to be measured accurately, variations were large, and small changes in motility could not be accurately evaluated. So, we tested the hypothesis that foam affects the motility of spermatozoa of Japanese quail by analyzing motility objectively using computer-assisted semen analysis and determining changes in sperm kinetics in the presence of different concentrations of proctodeal gland foam. The addition of 5% or 10% foam to the sperm suspension increased (P < 0.05) all sperm kinetic parameters (the curvilinear velocity, straight line velocity, the velocity of the average path, linearity, straightness, and beat cross frequency). As a result, the percentage of motile and progressive motile sperm also increased. All these parameters declined (P < 0.05) with a further increase in the concentration of foam to 15% and 20%. Furthermore, this effect was similar in males that were 8, 16, or 26 weeks of age. We conclude that sperm motility is enhanced by proctodeal gland foam, and this enhancement depends on its concentration. PMID:25301249

Farooq, U; Cho, S; Rybnik-Trzaskowska, P K; Singh, R P; Malecki, I A

2015-01-15

281

Effects of sera taken from women with recurrent spontaneous abortion on sperm motility and apoptosis  

PubMed Central

Background: Recurrent spontaneous abortion impacts almost 1% of couples. The sera from women with unexplained recurrent spontaneous abortion (URSA) have toxic effects on embryos that grow in the uterus. Therefore, the abnormal condition of the uterus may also affect sperm qualities. Objective: The objectives of this study were to search if these sera could induce DNA denaturation in sperm nuclei and also it could reduce sperm motility. Materials and Methods: Sera of 20 women with URSA history and sera from 20 women with at least two healthy children were added to the sperms samples from 20 healthy men for 2 hours. The sperm motility was assessed after incubation with sera. The samples were stained with Tdt mediated dUTP nick end labeling (TUNEL) assay for DNA fragmentation. The samples were analyzed with flow cytometry and the percentage of the TUNEL positive sperms were calculated. The data were analyzed by t-test. Results: The incubation of the sperm samples in sera with URSA lead to a decrease in the percentage of the motile sperm from 55% in control to 41% in the treated group, significantly (p=0.038). The percentage of the sperm with abnormal fragmented DNA increased after incubation with URSA (26.6%) compare to the control (21.2%); however, it was not significant. Conclusion: It seems that sera from URSA patients could not induce a significant increase in the percentage of the sperms with nuclei contain DNA fragmentation. However, the sera of women with URSA could affect the fertility rate by reduction of the sperm motility.

Talaei-khozani, Tahereh; Borzoei, Zahra; Bahmanpour, Soghra; Zolghadr, Jaleh; Dehbashi, Sedigheh; Zareh, Hamid Reza

2011-01-01

282

Sperm chromatin structure and male fertility: biological and clinical aspects  

Microsoft Academic Search

Aim:Sperm chromatin\\/DNA integrity is essential for the accurate transmission of paternal genetic information, and normal sperm chromatin structure is important for sperm fertilizing ability. The routine examination of semen, which includes sperm concentration, motility and morphology, does not identify defects in sperm chromatin structure. The origin of sperm DNA damage and a variety of methods for its assessment are described.

J. Erenpreiss; M. Spano; J. Erenpreisa; M. Bungum; A. Giwercman

2006-01-01

283

Cytogenetics of human sperm: meiotic segregation in two translocation carriers.  

PubMed Central

Meiotic segregation products were studied in sperm from two men heterozygous for the reciprocal translocations t(8;15)(p22;q21) and t(3;16)(p23;q24). A total of 226 and 201 sperm complements, respectively, were analyzed. In each translocation, 63% of complements were unbalanced, and alternate and adjacent 1 percentages were similar. The 3:1 segregation frequencies produced by the two translocations were 3.5% and 5.0%. Images Fig. 2 Fig. 3 Fig. 4 Fig. 5 PMID:3946422

Brandriff, B; Gordon, L; Ashworth, L K; Littman, V; Watchmaker, G; Carrano, A V

1986-01-01

284

Identifying X- and Y-chromosome-bearing sperm by DNA content: retrospective perspectives and prospective opinions  

SciTech Connect

Theoretically, since DNA should be the most constant component, quantitatively, of normal sperm, then genotoxic agents arising from energy production and consumption, and chemical and physical mutagens, could be identified by measuring variability in the DNA content of individual sperm from exposed men or test animals. The difference between the DNA content of X and Y sperm seemed a biologically significant benchmark for the measurement technology. Several methods are available for determining the genetic activity of agents in male germ cells, but these tests are generally laborious. Sperm-based methods provide an attractive alternate since they are not invasive, and are directly applicable to the study of human exposure. Slide-based assay of DNA content suggests that human sperm with X, Y, or YY chromosome constitutions can be distinguished by their fluorescence with quinacrine. Subsequent measurement of the dry mass of human sperm heads is performed. Dry mass is proportional to DNA content. While the study showed that human sperm with none and one quinacrine-fluorescent spot are X- and Y-bearing, respectively, the dry mass measurements indicated that many of the sperm with two quinacrine-fluorescent spots are not YY-bearing. While several reports on the initial application of flow cytometry of sperm to the investigation of mammalian infertility have appeared recently, emphasis here has been on the development of an in vivo sperm-based flow cytometric bioassay for mutations, and has not centered on andrological applications. In this review, the ability to differentiate between two equally sized populations of sperm, one bearing X and the other Y chromosomes with mean DNA content differing by about 3 to 4% is described. It has direct application to the preselection of sex of offspring, and could likely have a profound impact on animal improvement. (ERB)

Gledhill, B.L.; Pinkel, D.; Garner, D.L.

1982-03-05

285

No evidence of sperm conjugate formation in an Australian mouse bearing sperm with three hooks.  

PubMed

Sperm conjugation occurs when two or more sperm physically unite for motility or transport through the female reproductive tract. In many muroid rodent species, sperm conjugates have been shown to form by a single, conspicuous apical hook located on the sperm head. These sperm "trains" have been reported to be highly variable in size and, despite all the heads pointing in roughly the same direction, exhibit a relatively disordered arrangement. In some species, sperm "trains" have been shown to enhance sperm swimming speed, and thus have been suggested to be advantageous in sperm competition. Here, we assessed the behavior of sperm in the sandy inland mouse (Pseudomys hermannsburgensis), a muroid rodent that bears sperm with three apical hooks. First, we accrued genetic evidence of multiple paternity within "wild" litters to unequivocally show that sperm competition does occur in this species. Following this we utilized both in vitro and in vivo methodologies to determine whether sandy inland mouse sperm conjugate to form motile trains. Our observations of in vitro preparations of active sperm revealed that sandy inland mouse sperm exhibit rapid, progressive motility as individual cells only. Similarly, histological sections of the reproductive tracts of mated females revealed no in vivo evidence of sperm conjugate formation. We conclude that the unique, three-hooked morphology of the sandy inland mouse sperm does not facilitate the formation of motile conjugates, and discuss our findings in relation to the different hypotheses for the evolution of the muroid rodent hook/s. PMID:23919134

Firman, Renée C; Bentley, Blair; Bowman, Faye; Marchant, Fernando García-Solís; Parthenay, Jahmila; Sawyer, Jessica; Stewart, Tom; O'Shea, James E

2013-07-01

286

No evidence of sperm conjugate formation in an Australian mouse bearing sperm with three hooks  

PubMed Central

Sperm conjugation occurs when two or more sperm physically unite for motility or transport through the female reproductive tract. In many muroid rodent species, sperm conjugates have been shown to form by a single, conspicuous apical hook located on the sperm head. These sperm “trains” have been reported to be highly variable in size and, despite all the heads pointing in roughly the same direction, exhibit a relatively disordered arrangement. In some species, sperm “trains” have been shown to enhance sperm swimming speed, and thus have been suggested to be advantageous in sperm competition. Here, we assessed the behavior of sperm in the sandy inland mouse (Pseudomys hermannsburgensis), a muroid rodent that bears sperm with three apical hooks. First, we accrued genetic evidence of multiple paternity within “wild” litters to unequivocally show that sperm competition does occur in this species. Following this we utilized both in vitro and in vivo methodologies to determine whether sandy inland mouse sperm conjugate to form motile trains. Our observations of in vitro preparations of active sperm revealed that sandy inland mouse sperm exhibit rapid, progressive motility as individual cells only. Similarly, histological sections of the reproductive tracts of mated females revealed no in vivo evidence of sperm conjugate formation. We conclude that the unique, three-hooked morphology of the sandy inland mouse sperm does not facilitate the formation of motile conjugates, and discuss our findings in relation to the different hypotheses for the evolution of the muroid rodent hook/s. PMID:23919134

Firman, Renée C; Bentley, Blair; Bowman, Faye; Marchant, Fernando García-Solís; Parthenay, Jahmila; Sawyer, Jessica; Stewart, Tom; O'Shea, James E

2013-01-01

287

Computer-based tracking of single sperm.  

PubMed

This paper describes a robust single sperm tracking algorithm (SSTA) that can be used in laser optical trapping and sperm motility studies. The algorithm creates a region of interest (ROI) centered about a sperm selected by the user. SSTA contrast enhances the ROI image and implements a modified four-class thresholding method to extract the tracked sperm as it transitions in and out of focus. The nearest neighbor method is complemented with a speed-check feature to aid tracking in the presence of additional sperm or other particles. SSTA has a collision-detection feature for real or perceived collision or near-miss cases between two sperm. Subsequent postcollision analysis employs three criteria to distinguish the tracked sperm in the image. The efficacy of SSTA is validated through examples and comparisons to commercially available computer-aided sperm tracking systems. PMID:17092158

Shi, Linda Z; Nascimento, Jaclyn M; Berns, Michael W; Botvinick, Elliot L

2006-01-01

288

Analysis of 232 total fertilization failure cycles during intracytoplasmic sperm injection  

PubMed Central

Background: The intracytoplasmic sperm injection procedure ending with total fertilization failure is very distressfull event for both the clinician and the patient. Objective: The aim of this study was to identify independent factors which could be used to identify total fertilization failure before the day of intracytoplasmic sperm injection. Materials and Methods: This was a retrospective study of 232 patients who were admitted to a tertiary-care hospital IVF Unit and showed total fertilization failure during intracytoplasmic sperm injection cycles. To sort out the interwined effects of female age, basal FSH, sperm quality, antral follicle count, starting dose of gonadotrophine, sperm extraction technique, cycle length, >14 mm follicle number, oocyte number after oocyte pick up, estradiol and progesterone level on the day of hCG and the MI, MII and GV oocyte number on the fertilization, multiple logistic regression analysis was used. Results: The total fertilization failure rate was 6% and the recurrance rate was 23%. The original model illustrated that the presence of GV oocytes, total oocyte number less than six, <2000 pg/mL E2 concentration on the day of hCG and testicular sperm extraction increases the total fertilization failure risk. Conclusion: It is very difficult to predict total fertilization failure. Sometimes even with one good quality oocyte and sperm and in the case of globozoospermia fertilization can be achieved. Not only azoospermia but also low oocyte numbers increase the chance of total fertilization failure even after intracytoplasmic sperm injection.

Sarikaya, Esma; Eryilmaz, Ozlem Gun; Deveer, Ruya; Dogan, Muammer; Mollamahmutoglu, Leyla

2011-01-01

289

Effects of dietary n-3 fatty acids on characteristics and lipid composition of ovine sperm.  

PubMed

The fatty acid composition of sperm affects the fertilization rate. The objective was to investigate the effects of dietary fish oil (as a source of n-3 fatty acids) on semen quality and sperm fatty acid composition in sheep. Eight Zandi fat-tailed rams were randomly allocated into two groups and fed either a control diet or a diet supplemented with fish oil. Both diets were isocaloric and isonitrogenous and were fed for 13 weeks, starting in the middle of the breeding season. Semen samples were collected weekly and their characteristics evaluated by standard methods, whereas samples collected at the start and end of the study were assessed (gas chromatography) for sperm lipid composition. Mean (±s.e.m.) sperm concentrations (4.3 × 109 ± 1.3 × 108 v. 3.9 × 109 ± 1.3 × 108 sperm/ml and percentages of motile (77.25 ± 3.34 v. 60.8 ± 3.34) and progressively motile sperm (74.13 ± 1.69 v. 62.69 ± 1.69) were significantly higher in the fish oil group than control. Dietary fish oil increased the proportion of docosahexaenoic acid (DHA, C22:6 n-3) in sperm fatty acid composition. We concluded that feeding fish oil as a source of n-3 fatty acids attenuated seasonal declines in semen quality in rams, perhaps through increased DHA in sperm. PMID:22445376

Samadian, F; Towhidi, A; Rezayazdi, K; Bahreini, M

2010-12-01

290

Mice lacking FABP9/PERF15 develop sperm head abnormalities but are fertile.  

PubMed

The male germ cell-specific fatty acid-binding protein 9 (FABP9/PERF15) is the major component of the murine sperm perforatorium and perinuclear theca. Based on its cytoskeletal association and sequence homology to myelin P2 (FABP8), it has been suggested that FABP9 tethers sperm membranes to the underlying cytoskeleton. Furthermore, its upregulation in apoptotic testicular germ cells and its increased phosphorylation status during capacitation suggested multiple important functions for FABP9. Therefore, we investigated specific functions for FABP9 by means of targeted gene disruption in mice. FABP9(-/-) mice were viable and fertile. Phenotypic analysis showed that FABP9(-/-) mice had significant increases in sperm head abnormalities (~8% greater than their WT cohorts); in particular, we observed the reduction or absence of the characteristic structural element known as the "ventral spur" in ~10% of FABP9(-/-) sperm. However, deficiency of FABP9 affected neither membrane tethering to the perinuclear theca nor the fatty acid composition of sperm. Moreover, epididymal sperm numbers were not affected in FABP9(-/-) mice. Therefore, we conclude that FABP9 plays only a minor role in providing the murine sperm head its characteristic shape and is not absolutely required for spermatogenesis or sperm function. PMID:20920498

Selvaraj, Vimal; Asano, Atsushi; Page, Jennifer L; Nelson, Jacquelyn L; Kothapalli, Kumar S D; Foster, James A; Brenna, J Thomas; Weiss, Robert S; Travis, Alexander J

2010-12-15

291

Multiple sperm storage organs facilitate female control of paternity  

PubMed Central

It has been proposed that multiple sperm storage organs (spermathecae) could allow polyandrous females to control paternity. There is little conclusive evidence for this since insemination of individual spermathecae is generally not experimentally manipulable. Here, we examined sperm use patterns in the Australian redback spider (Latrodectus hasselti), which has paired, independent spermathecae. We assessed paternity when two rivals were forced to inseminate a single storage organ or opposite storage organs. When males inseminated a single spermatheca, mean paternity of the female's first mate was 79.8% (median 89.4%), and 38% of first mates achieved 100% paternity. In contrast, when males inseminated opposite organs, the mean paternity of the first mate was 49.3% (median 49.9%), only 10% of males achieved complete precedence, and paternity was normally distributed, suggesting sperm mixing. Males responded to this difference by avoiding previously inseminated female reproductive tracts. Complete sperm precedence can only be achieved if females permit males to copulate with both reproductive tracts. Females often cannibalize smaller males during their first copulation, thus limiting their paternity to 50%. These data show that multiple sperm storage organs can increase female control of paternity. PMID:16024375

Snow, Lindsay S.E; Andrade, Maydianne C.B

2005-01-01

292

GLYCERALDEHYDE 3-PHOSPHATE DEHYDROGENASE-S, A SPERM-SPECIFIC GLYCOLYTIC ENZYME, IS REQUIRED FOR SPERM MOTILITY AND MALE FERTILITY  

EPA Science Inventory

While glycolysis is highly conserved, it is remarkable that several novel isozymes in this central metabolic pathway are found in mammalian sperm. Glyceraldehyde 3-phosphate dehydrogenase-S (GAPDS) is the product of a mouse gene expressed only during spermatogenesis and, like it...

293

Photobiomodulation with light-emitting diodes improves sperm motility in men with asthenozoospermia.  

PubMed

Sperm motility is an important parameter of male fertility and depends on energy consumption. Photobiomodulation with light-emitting diode (LED) is known to stimulate respiratory chain in mitochondria of different mammalian cells. The aim of this research was to evaluate the effect of photobiomodulation with LED on sperm motility in infertile men with impaired sperm motility-asthenozoospermia. Thirty consecutive men with asthenozoospermia and normal sperm count who visited the infertility clinic of University Medial Centre Ljubljana between September 2011 and February 2012 were included in the study. Semen sample of each man was divided into five parts: one served as a non-treated (native) control and four parts were irradiated with LED of different wavelengths: (1) 850 nm, (2) 625, 660 and 850 nm, (3) 470 nm and (4) 625, 660 and 470 nm. The percentage of motile sperm and kinematic parameters were measured using a Sperm Class Analyser system following the WHO recommendations. In the non-treated semen samples, the average ratio of rapidly progressive sperms was 12 % and of immotile sperm 73 %. Treating with LED significantly increased the proportion of rapidly progressive sperm (mean differences were as follows: 2.83 (1.39-4.28), 3.33 (1.61-5.05), 4.50 (3.00-5.99) and 3.83 (2.31-5.36) for groups 1-4, respectively) and significantly decreased the ratio of immotile sperm (the mean differences and 95 % CI were as follows: 3.50 (1.30-5.70), 4.33 (2.15-6.51), 5.83 (3.81-7.86) and 5.50 (2.98-8.02) for groups 1-4, respectively). All differences were highly statistically significant. This finding confirmed that photobiomodulation using LED improved the sperm motility in asthenozoospermia regardless of the wavelength. PMID:25204851

Ban Frangez, Helena; Frangez, Igor; Verdenik, Ivan; Jansa, Vid; Virant Klun, Irma

2014-09-10

294

Airborne sperm of Conocephalum conicum (Conocephalaceae).  

PubMed

We have obtained the first momentary photographs of sperms just as they are discharged from the antheridium of a liverwort, Conocephalum conicum, and have succeeded in monitoring the airborne sperms of bryophytes under field conditions. Airborne sperm of liverworts seems to be an effective strategy for raising the efficiency of fertilization between male and female plants separated in a drought environment. PMID:18058191

Shimamura, Masaki; Yamaguchi, Tomio; Deguchi, Hironori

2008-01-01

295

Rescue of germline transmission from chimeras by IVF after sperm analysis.  

PubMed

Successful production of genetically modified mouse lines is dependent on germline transmission (GLT) of mutant alleles from chimeras. When natural mating fails to achieve GLT due to male infertility, sickness, or other problems, sperm can be harvested from chimeras and used for assisted reproductive technologies such as in vitro fertilization (IVF) to attempt to "rescue" GLT. However, a rational, evidence-based approach to determine if such extraordinary efforts should be attempted on a chimera has not been established. Therefore, in the present study we assessed the production, quality and genotype of epididymal sperm harvested from male chimeras generated by blastocyst or morula microinjection of gene targeted embryonic stem (ES) cell clones containing a LacZ expression cassette and that failed to achieve GLT. Results of this analysis enabled us to determine the cause of GLT failure, correlate coat color chimerism with the proportion of LacZ-positive sperm, and test the likelihood of achieving GLT by IVF. In 415 chimeras, 332 (80 %) produced no offspring by natural mating ("infertile"), while 83 (20 %) produced only wildtype offspring ("fertile"). Of the 332 infertile chimeras, 209 (63 %) failed to produce any sperm whatsoever, 48 (15 %) had extremely poor quality sperm, and 75 (23 %) had good quality sperm. These results indicate that most chimeras that do not achieve GLT by natural mating are infertile, and the primary cause of infertility is failed spermatogenesis. Genotyping of sperm from 519 chimeras revealed a significant positive linear correlation between coat color chimerism and mean percentage of LacZ-positive sperm (R(2) = 0.95). Finally, IVF using good quality, LacZ-positive sperm from fertile and infertile chimeras "rescued" GLT for 19 out of 56 genes. We conclude that an assessment of coat color chimerism together with sperm quality and genotype can better inform the selection of chimeras for IVF to rescue GLT than coat color chimerism alone. PMID:25080098

Li, Ming-Wen; Willis, Brandon J; Evans, Kristin D; Araiza, Renee S; Lee, Angus Yiu-Fai; Lloyd, K C Kent

2015-02-01

296

Pathological changes in metabolism of poultry related to increasing production levels  

Microsoft Academic Search

A continuously increasing production level in poultry breeding has resulted in changes in metabolism. Selection procedures in breeding programmes are focused on an increase in growth rate and on a decrease in feed conversion ratio (less feed intake per unit of deposited tissue). These procedures do not pay attention to the maintenance requirements of birds. Imbalances between production (protein and

C. W. Scheele

1997-01-01

297

Membrane proteins associated with sperm-oocyte interaction: A proteomic comparison between Kedah Kelantan (Bos indicus) and Mafriwal (Bos taurus × Bos indicus) sperm  

NASA Astrophysics Data System (ADS)

Production performance of European cattle breeds has significantly improved through various breeding programs. However, European breeds are more susceptible to heat stress compared to zebu cattle (Bos indicus) as their conception rate can range between 20 to 30% in hot seasons compared to winter. To identify cattle sperm proteins associated with zebu cattle higher fertility and heat tolerance in tropical environments, we utilised a proteomics-based approach to compare sperm from the highly fertile Malaysian indigenous breed, Kedah Kelantan (Bos indicus), with sperm from the sub-fertile crossbreed, Mafriwal (Bos taurus × Bos indicus). Frozen semen of three high performance bulls from each breed was processed to obtain live and pure sperm. Proteins were separated and gel bands were processed by in-gel tryptic digestion. For each breed, mass spectrometry data was acquired over 11 replicates. The analyzed data identified peptides with different expression levels (99% confidence level) and protein identification was determined by targeted MS/MS. Among the identified proteins associated with sperm-oocyte interaction, two proteins were up-regulated in Kedah Kelantan sperm and 7 proteins were up-regulated in or specific to Mafriwal. Our results suggest that the higher fertility of zebu cattle in tropical areas may not be related to more efficient sperm-oocyte interaction. Further analysis of the other regulated proteins in these two breeds may contribute further knowledge on the physiological reason/s for higher fertility and heat tolerance of Zebu cattle in tropical areas.

Ashrafzadeh, Ali; Nathan, Sheila; Othman, Iekhsan; Yee, Tee Ting; Karsani, Saiful Anuar

2013-11-01

298

The effects of opiate consumption on serum reproductive hormone levels, sperm parameters, seminal plasma antioxidant capacity and sperm DNA integrity.  

PubMed

We evaluated the effects of opiate consumption on semen quality, sperm function, seminal plasma antioxidant capacity, and sperm DNA integrity. A total of 142 opiate addict men (group 1) were enrolled in the study and 146 healthy age matched male volunteers (group 2) served as controls. Two semen analyses were performed in all participants. Sperm chromatin structure assay (SCSA) was used to identify sperm DNA integrity. The mean±SD sperm concentration in opiate users and in control subjects was 22.2±4.4 and 66.3±8.3 million per ml, respectively (P=0.002). A significant increase in the amount of fragmented DNA was found in opiate consumers compared with that in controls (36.4±3.8% vs. 27.1±2.4%, P=0.004). Significantly decreased levels of catalase-like and superoxide dismutase-like (SOD) activity were observed in group 1 compared with group 2. Opiate consumption has significant adverse effects on semen quality. In cases of unexplained infertility in men, opium consumption should be considered as a possible factor. PMID:23207164

Safarinejad, Mohammad Reza; Asgari, Seyyed Alaeddin; Farshi, Alireza; Ghaedi, Gholamhossein; Kolahi, Ali Asghar; Iravani, Shahrokh; Khoshdel, Ali Reza

2013-04-01

299

Beneath the Arctic Green: Have recent increases in plant production been offset by increases in soil decomposition?  

NASA Astrophysics Data System (ADS)

Observational and modeling studies suggest that boreal vegetation has undergone an increase in plant production and C uptake in recent decades, coincident with increases in regional air temperatures, atmospheric CO2 concentration, and fire/successional dynamics. In the North American boreal forest, wildfires have increased in extent, season length, and depth of burn, driving higher C emission from black spruce ecosystems. Meanwhile, responses in soil systems that dictate the net ecosystem carbon (C) balance are less well known, in part owing to problems with elucidating the relatively small signals of organic matter decomposition from the large C fluxes of gross primary production and ecosystem respiration. Here, we measured net C accumulation in soils from Interior Alaska using radiocarbon (14C), lead isotopes (210Pb), cesium isotopes (137Cs), and time sequences of forest regeneration (fire and thaw chronosequences). We use soil 14C and non-steady-state models to estimate turnover times for soil organic C. Over the past century, rates of soil C uptake based on upland chronosequences ranged from -20 to -30 g C/m2/yr, but regionally likely shifted toward a reduced sink or source of - 20 to + 10 g C/m2/yr in recent decades due to increased combustion losses and deep C mobilization associated with permafrost thaw. C accumulation rates in lowland thermokarst chronosequences suggest a mixed sink/source effect, with post-thaw increases in surface accumulation potentially offset by decomposition at depth, or enhanced initial decomposition of C from previously frozen soils, followed by long-term net uptake of post-thaw peat. Large uncertainties remain regarding the turnover of soil organic C in boreal soil, yet enhanced decomposition has likely offset the increase in NPP, resulting in a reduced sink activity relative to pre1960s.

Harden, J. W.; O'Donnell, J.; Fuller, C.; Sierra, C. A.; Johnson, K. D.; Manies, K.; Jorgenson, T.; Jones, M.; Ewing, S. A.; Yue, C.; Turetsky, M.

2013-12-01

300

Oxytocin increases extrapancreatic glucagon secretion and glucose production in pancreatectomized dogs  

SciTech Connect

Infusion of oxytocin into normal dogs increases plasma levels of insulin and glucagon and glucose production and uptake. To determine whether infused oxytocin also increases glucagon secretion from extrapancreatic sites, pancreatectomized dogs, off insulin of 18 hr, were infused with oxytocin and plasma glucagon, and glucose production and uptake were measured using the (6-/sup 3/H)glucose primer-infusion technique. The diabetic dogs, in the control period, had elevated plasma glucose and glucagon levels, an increased rate of glucose production, and a relative decrease in glucose uptake (decreased clearance). Infusion of oxytocin (500 ..mu..U/kg/min) caused a rise in plasma glucagon and glucose levels, increased glucose production, and further decreased glucose clearance. it is concluded that oxytocin can stimulate secretion of extrapancreatic glucagon, which contributes to the increased glucose production.

Altszuler, N.; Puma, F.; Winkler, B.; Fontan, N.; Saudek, C.D.

1986-05-01

301

Choline Dehydrogenase Polymorphism rs12676 Is a Functional Variation and Is Associated with Changes in Human Sperm Cell Function  

PubMed Central

Approximately 15% of couples are affected by infertility and up to half of these cases arise from male factor infertility. Unidentified genetic aberrations such as chromosomal deletions, translocations and single nucleotide polymorphisms (SNPs) may be the underlying cause of many cases of idiopathic male infertility. Deletion of the choline dehydrogenase (Chdh) gene in mice results in decreased male fertility due to diminished sperm motility; sperm from Chdh?/? males have decreased ATP concentrations likely stemming from abnormal sperm mitochondrial morphology and function in these cells. Several SNPs have been identified in the human CHDH gene that may result in altered CHDH enzymatic activity. rs12676 (G233T), a non-synonymous SNP located in the CHDH coding region, is associated with increased susceptibility to dietary choline deficiency and risk of breast cancer. We now report evidence that this SNP is also associated with altered sperm motility patterns and dysmorphic mitochondrial structure in sperm. Sperm produced by men who are GT or TT for rs12676 have 40% and 73% lower ATP concentrations, respectively, in their sperm. rs12676 is associated with decreased CHDH protein in sperm and hepatocytes. A second SNP located in the coding region of IL17BR, rs1025689, is linked to altered sperm motility characteristics and changes in choline metabolite concentrations in sperm. PMID:22558321

Johnson, Amy R.; Lao, Sai; Wang, Tongwen; Galanko, Joseph A.; Zeisel, Steven H.

2012-01-01

302

Altered sperm chromatin structure in mice exposed to sodium fluoride through drinking water.  

PubMed

This study investigated the effects of sodium fluoride (NaF) on sperm abnormality, sperm chromatin structure, protamine 1 and protamine 2 (P1 and P2) mRNA expression, and histones expression in sperm in male mice. NaF was orally administrated to male mice at 30, 70, and 150 mg/l for 49 days (more than one spermatogenic cycle). Sperm head and tail abnormalities were significantly enhanced at middle and high doses. Similarly, sperm chromatin structure was also adversely affected by NaF exposure, indicating DNA integrity damage. Furthermore, middle and high NaF significantly reduced the mRNA expressions of P1 and P2, and P1/P2 ratio, whereas the sperm histones level was increased, suggesting the abnormal histone-protamine replacement. Therefore, we concluded that the mechanism by which F induced mice sperm abnormality and DNA integrity damage may involved in the alterations in P1, P2, and histones expression in sperm of mice. PMID:22865829

Sun, Zilong; Niu, Ruiyan; Wang, Bin; Wang, Jundong

2014-06-01

303

Effects of Hoechst33342 staining on the viability and flow cytometric sex-sorting of frozen-thawed ram sperm.  

PubMed

Cytometric sorting of frozen-thawed sperm can overcome difficulties caused by the unavailability of sorting facilities on farms where semen is collected from male livestock. In order to optimize the cytometric sex-sorting procedure, effects of Hoechst33342 staining on the viability and cytometric sorting efficiency of frozen-thawed ram sperm were evaluated. The frozen-thawed sperm were stained with Hoechst33342 at various dye concentrations (80?M, 120?M, 160?M, 200?M, 240?M, or 320?M) for 45min to evaluate effects of dye dose. The frozen-thawed sperm were stained with 160?M Hoechst33342 for various durations (0min, 15min, 30min, 45min, 60min, 75min, or 90min) to evaluate effects of staining duration. Sperm motility and moving velocity were analyzed using a computer-assisted sperm analysis system (CASAS). Acrosome status, membrane integrity, and distribution of phosphatidylserine (PS) in Hoechst33342-stained sperm were analyzed using flow cytometry after staining with fluorescein isothiocyanate-labeled lectin from pisum sativum (FITC-PSA), Annexin V, or propidium iodide (PI). The fertility of Hoechst33342-stained sperm was analyzed by in vitro fertilization (IVF). A high-speed cell sorter was used to evaluate effects of Hoechst33342 staining on cytometric sex-sorting of frozen-thawed sperm. The motility, moving velocity, membrane integrity, and PS distribution of Hoechst33342-stained sperm were significantly different from that of immediately thawed sperm (P<0.05). However, there is no significant difference existing among the Hoechst33342-stained groups with respect to the above evaluated parameters. Additionally, along with the staining durations, the adverse effects of the staining procedure on sperm showed a steady increase. However, Hoechst33342 staining did not damage acrosome and in vitro fertilizing capability of frozen-thawed ram sperm. Results of cytometric sorting indicated that frozen-thawed sperm can be efficiently sorted into two sperm populations with X and Y chromosome when the Hoechst33342 concentration was 160?M. Moreover, when the staining duration was equal to or longer than 45min, the frozen-thawed sperm can be successfully sorted in the presence of 160?M Hoechst33342. In conclusion, Hoechst33342 staining can detrimentally influence viability of frozen-thawed ram sperm except acrosome and in vitro fertilizing capability. Accordingly, the minimum values of Hoechst33342 concentration and staining duration can be set at 160?M and 45min respectively. However, the maximum values of Hoechst33342 concentration and staining duration were not determined based on the current study. Further research on how to reduce injuries caused by freezing, thawing, and Hoechst33342 staining on frozen-thawed ram sperm is needed. PMID:25481668

Quan, Guo Bo; Ma, Yuan; Li, Jian; Wu, Guo Quan; Li, Dong Jiang; Ni, Yi Na; Lv, Chun Rong; Zhu, Lan; Hong, Qiong Hua

2015-02-01

304

When 'sperm' becomes 'donor': Transitions in parents' views of the sperm donor.  

PubMed

Abstract Little is known about recipients' views of their sperm donor. This study aimed to examine the possible transitions or consistencies in donor sperm recipients' (DSRs') view on the sperm donor over time. A longitudinal qualitative study of 19 Belgian heterosexual DSRs was undertaken. Interviews took place with both partners of the couple during pregnancy, at birth and 1.5-2 years after birth, and were analysed using a grounded theory approach. Recipients who intended to disclose exhibited a transition in their awareness of the donor from being of minimal importance to one who was increasingly seen as part of their family narrative. This was partly triggered by the offspring's life, remarks about resemblance and the socio-cultural context. The perceived position of the donor changed for most recipients from a threatening rival to a 'distractor'. This change was supported by the emerging father-child bond and the confidence that stemmed from it. These observations were applicable to those recipients who intended to disclose their donor conception; for those recipients who intended not to disclose, little or no transition was observed. This study describes and analyses the transitions and consistencies in recipients' views of the donor over different stages of the family life-cycle (pregnancy, birth, toddler stage) and could help the fertility clinics tailor their counselling to the specific stages of parenthood. PMID:24851674

Indekeu, Astrid; D'Hooghe, Thomas; Daniels, Ken R; Dierickx, Kris; Rober, Peter

2014-12-01

305

Evaluation of antioxidant effects of crocin on sperm quality in cyclophosphamide treated adult mice  

PubMed Central

Cyclophosphamide (CP) is one of the anti-neoplastic drugs. Despite its numerous clinical applications, it has devastating effects on the testicles and declines the sperm quality in treated patients. This study was aimed to investigate the protective effect of crocin in improving the toxicity induced by CP in reproductive system. In this study, 24 male adult mice (6 to 8 weeks) were randomly divided into three groups, control group received normal saline (0.1 mL, IP, daily), the CP group received CP (15 mg kg-1, IP, weekly) and the CP + crocin group received CP along with crocin (200 mg kg-1, IP, daily). After 35 days of treatment, animals were sacrificed. The samples of epididymis in human tubal fluid medium incubated for 30 min in 5% CO2 for flotation of sperm. Sperm were obtained from caudal epididymis using dissecting method. Then, the parameters of sperm quality including sperm count, motility, viability, DNA damage, nuclear maturation, and sperm morphology were evaluated. In CP group, the sperm count, motility, viability, nuclear maturation and sperm morphology were significantly decreased compared to control group (p < 0.05) and in the CP + crocin group all of these parameters significantly increased compared to CP group (p < 0.05). The percentage of sperm with DNA damage in the CP group significantly increased compared to other groups (p < 0.05). The results of this study indicated that the crocin was able to suppress free radicals and enhance the quality of sperm in CP treated animals. PMID:25568721

Bakhtiary, Zahra; Shahrooz, Rasoul; Ahmadi, Abbas; Zarei, Leila

2014-01-01

306

Evaluation of antioxidant effects of crocin on sperm quality in cyclophosphamide treated adult mice.  

PubMed

Cyclophosphamide (CP) is one of the anti-neoplastic drugs. Despite its numerous clinical applications, it has devastating effects on the testicles and declines the sperm quality in treated patients. This study was aimed to investigate the protective effect of crocin in improving the toxicity induced by CP in reproductive system. In this study, 24 male adult mice (6 to 8 weeks) were randomly divided into three groups, control group received normal saline (0.1 mL, IP, daily), the CP group received CP (15 mg kg(-1), IP, weekly) and the CP + crocin group received CP along with crocin (200 mg kg(-1), IP, daily). After 35 days of treatment, animals were sacrificed. The samples of epididymis in human tubal fluid medium incubated for 30 min in 5% CO2 for flotation of sperm. Sperm were obtained from caudal epididymis using dissecting method. Then, the parameters of sperm quality including sperm count, motility, viability, DNA damage, nuclear maturation, and sperm morphology were evaluated. In CP group, the sperm count, motility, viability, nuclear maturation and sperm morphology were significantly decreased compared to control group (p < 0.05) and in the CP + crocin group all of these parameters significantly increased compared to CP group (p < 0.05). The percentage of sperm with DNA damage in the CP group significantly increased compared to other groups (p < 0.05). The results of this study indicated that the crocin was able to suppress free radicals and enhance the quality of sperm in CP treated animals. PMID:25568721

Bakhtiary, Zahra; Shahrooz, Rasoul; Ahmadi, Abbas; Zarei, Leila

2014-01-01

307

Increasing Student Interest and Comprehension of Production Planning and Control and Operations Performance Measurement Concepts Using a Production Line Game  

ERIC Educational Resources Information Center

Production planning and control (PPC) systems and operations performance measures are topics that students generally find both boring and difficult to understand. In the article, the authors present a production line game that they have found to be an effective tool to increase student interest in the topics as well as student comprehension. The…

Cox, James F., III; Walker, Edward D., II

2005-01-01

308

Inclusion of glycerol in forage diets increases methane production in a rumen simulation technique system.  

PubMed

We hypothesised that the inclusion of glycerol in the forage diets of ruminants would increase the proportion of propionate produced and thereby decrease in vitro CH? production. This hypothesis was examined in the present study using a semi-continuous fermentation system (rumen simulation technique) fed a brome hay (8·5 g) and maize silage (1·5 g) diet with increasing concentrations (0, 50, 100 and 150 g/kg DM) of glycerol substituted for maize silage. Glycerol linearly increased total volatile fatty acids production (P<0·001). Acetate production was quadratically affected (P=0·023) and propionate and butyrate production was linearly increased (P<0·001). Glycerol linearly increased (P=0·011) DM disappearance from hay and silage. Crude protein disappearance from hay was not affected (P=0·789), but that from silage was linearly increased (P<0·001) with increasing glycerol concentrations. Neutral-detergent fibre (P=0·040) and acid-detergent fibre (P=0·031) disappearance from hay and silage was linearly increased by glycerol. Total gas production tended to increase linearly (P=0·061) and CH? concentration in gas was linearly increased (P<0·001) by glycerol, resulting in a linear increase (P<0·001) in mg CH?/g DM digested. Our hypothesis was rejected as increasing concentrations of glycerol in a forage diet linearly increased CH? production in semi-continuous fermenters, despite the increases in the concentrations of propionate. In conclusion, this apparent discrepancy is due to the more reduced state of glycerol when compared with carbohydrates, which implies that there is no net incorporation of electrons when glycerol is metabolised to propionate. PMID:24094291

Avila-Stagno, Jorge; Chaves, Alexandre V; Ribeiro, Gabriel O; Ungerfeld, Emilio M; McAllister, Tim A

2014-03-14

309

Why small males have big sperm: dimorphic squid sperm linked to alternative mating behaviours  

PubMed Central

Background Sperm cells are the target of strong sexual selection that may drive changes in sperm structure and function to maximize fertilisation success. Sperm evolution is regarded to be one of the major consequences of sperm competition in polyandrous species, however it can also be driven by adaptation to the environmental conditions at the site of fertilization. Strong stabilizing selection limits intra-specific variation, and therefore polymorphism, among fertile sperm (eusperm). Here we analyzed reproductive morphology differences among males employing characteristic alternative mating behaviours, and so potentially different conditions of sperm competition and fertilization environment, in the squid Loligo bleekeri. Results Large consort males transfer smaller (average total length = 73 ?m) sperm to a female's internal sperm storage location, inside the oviduct; whereas small sneaker males transfer larger (99 ?m) sperm to an external location around the seminal receptacle near the mouth. No significant difference in swimming speed was observed between consort and sneaker sperm. Furthermore, sperm precedence in the seminal receptacle was not biased toward longer sperm, suggesting no evidence for large sperm being favoured in competition for space in the sperm storage organ among sneaker males. Conclusions Here we report the first case, in the squid Loligo bleekeri, where distinctly dimorphic eusperm are produced by different sized males that employ alternative mating behaviours. Our results found no evidence that the distinct sperm dimorphism was driven by between- and within-tactic sperm competition. We propose that presence of alternative fertilization environments with distinct characteristics (i.e. internal or external), whether or not in combination with the effects of sperm competition, can drive the disruptive evolution of sperm size. PMID:21831296

2011-01-01

310

Anatase titanium dioxide nanoparticles in mice: evidence for induced structural and functional sperm defects after short-, but not long-, term exposure.  

PubMed

Titanium dioxide (TiO 2 ) nanoparticles (TNPs) are widely used commercially and exist in a variety of products. To determine if anatase TNPs (ATNPs) in doses smaller than previously used reach the scrotum after entry in the body at a distant location and induce sperm defects, 100% ATNP (2.5 or 5 mg kg-1 body weight) was administered intraperitoneally to adult males for three consecutive days, followed by sacrifice 1, 2, 3, or 5 weeks later (long-) or 24, 48 or 120 h (short-term exposure). Transmission electron microscopy revealed the presence of ANTP in scrotal adipose tissues collected 120 h postinjection when cytokine evaluation showed an inflammatory response in epididymal tissues and fluid. At 120 h and up to 3 weeks postinjection, testicular histology revealed enlarged interstitial spaces. Significantly increased numbers of terminal deoxyribonucleotidyl transferase-mediated dUTP nick-end labeling-positive (apoptotic) germ (P = 0.002) and interstitial space cells (P = 0.04) were detected in treated males. Caudal epididymal sperm from the short-term, but not a long-term, arm showed significantly (P < 0.001) increased frequencies of flagellar abnormalities, excess residual cytoplasm (ERC), and unreacted acrosomes in treated versus controls (dose-response relationship). A novel correlation between ERC and unreacted acrosomes was uncovered. At 120 h, there were significant decreases in hyperactivated motility (P < 0.001) and mitochondrial membrane potential (P < 0.05), and increased reactive oxygen species levels (P < 0.00001) in treated versus control sperm. These results indicate that at 4-8 days postinjection, ANTP induce structural and functional sperm defects associated with infertility, and DNA damage via oxidative stress. Sperm defects were transient as they were not detected 10 days to 5 weeks postinjection. PMID:25370207

Smith, Michelle A; Michael, Rowan; Aravindan, Rolands G; Dash, Soma; Shah, Syed I; Galileo, Deni S; Martin-DeLeon, Patricia A

2014-10-24

311

Isolation of Meiotic Recombinants from Mouse Sperm  

PubMed Central

Homologous recombination during meiosis is critical for the formation of gametes. Recombination is initiated by programmed DNA double-strand breaks which preferentially occur at hotspots dispersed throughout the genome. These double-strand breaks are repaired from the homolog, resulting in either a crossover or noncrossover product. Multiple noncrossover events are required for homolog pairing, and at least one crossover is critical for proper chromosome segregation at the first meiotic division. Consequently, homologous recombination in meiosis occurs at high frequencies. This chapter describes how to characterize crossovers and noncrossovers at a hotspot in mice using allele-specific PCR. Amplification of recombinant products directly from sperm DNA is a powerful approach to determine recombination frequencies and map recombination breakpoints, providing insight into homologous recombination mechanisms. PMID:21660699

Cole, Francesca; Jasin, Maria

2013-01-01

312

Panax ginseng induces the expression of CatSper genes and sperm hyperactivation  

PubMed Central

The cation channel of sperm (CatSper) protein family plays important roles in male reproduction and infertility. The four members of this family are expressed exclusively in the testis and are localized differently in sperm. To investigate the effects of Panax ginseng treatment on the expression of CatSper genes and sperm hyperactivation in male mice, sperm motility and CatSper gene expression were assessed using a computer-assisted semen analysis system, a Fluoroskan Ascent microplate fluorometer to assess Ca2+ influx, real-time polymerase chain reaction, Western blotting and immunofluorescence. The results suggested that the Ca2+ levels of sperm cells treated with P. ginseng were increased significantly compared with the normal group. The P. ginseng-treated groups showed increased sperm motility parameters, such as the curvilinear velocity and amplitude of lateral head displacement. Taken together, the data suggest that CatSper messenger ribonucleic acid levels were increased significantly in mouse testes in the P. ginseng-treated group, as was the protein level, with the exception of CatSper2. In conclusion, P. ginseng plays an important role in improving sperm hyperactivation via CatSper gene expression. PMID:24969054

Park, Eun Hwa; Kim, Do Rim; Kim, Ha Young; Park, Seong Kyu; Chang, Mun Seog

2014-01-01

313

A volatile inhibitor immobilizes sea urchin sperm in semen by depressing the intracellular pH  

SciTech Connect

Sea urchin spermatozoa are normally immotile in semen, but motility can be initiated by increasing gas flow over the semen--for example, by blowing N2 gas over a thin layer of semen. This result indicates that sperm motility is not O2 limited and suggests that seminal fluid contains a volatile inhibitor of motility which is responsible for the paralysis of sperm in semen. This inhibitor might be carbon dioxide, which reversibly immobilizes sperm. /sup 31/P-NMR measurements of pH show that the sperm intracellular pH (pHi) increases by 0.36 pH unit upon dilution of semen into seawater. Since previous studies have shown that this magnitude of pH increase is sufficient to trigger sperm motility, we suggest that the volatile inhibitor is inhibiting sperm motility in semen by depressing the pHi. A simple hypothesis that explains these observations is that the volatile motility inhibitor is CO/sub 2/, which could acidify pHi as a diffusable weak acid. In this regard, sperm diluted into seawater release acid, and this acid release is related to the pHi increase and motility initiation. In fact, nearly half of the acid released by sperm upon dilution is volatile and may therefore be due to CO/sub 2/ efflux. Most of the acid, however, cannot be attributed to CO/sub 2/ release because it is not volatile. Thus, when sperm are diluted into seawater, they raise their pHi by releasing CO/sub 2/ and protons from the cytoplasm into the surrounding seawater.

Johnson, C.H.; Clapper, D.L.; Winkler, M.M.; Lee, H.C.; Epel, D.

1983-08-01

314

NEW OBSERVATIONS ON OVIDUCTAL SPERM STORAGE, TRANSPORT AND SELECTION IN TURKEYS: RELEVANCE TO ARTIFICIAL INSEMINATION TECHNOLOGY  

Technology Transfer Automated Retrieval System (TEKTRAN)

Increased fundamental knowledge of the cellular and molecular mechanisms regulating oviductal sperm transport, selection and storage will provide logical, science-based approaches (versus an exclusively empirical approach) toward the development of novel semen diluent formulation and semen storage t...

315

Increasing nitrogen deposition enhances post-drought recovery of grassland productivity in the Mongolian steppe.  

PubMed

Arid regions are prone to drought because annual rainfall accumulation depends on a few rainfall events. Natural plant communities are damaged by drought, but atmospheric nitrogen (N) deposition may enhance the recovery of plant productivity after drought. Here, we investigated the effect of increasing N deposition on post-drought recovery of grassland productivity in the Mongolian steppe, and we examined the influence of grazing in this recovery. We added different amounts of N to a Mongolian grassland during two sequential drought years (2006 and 2007) and the subsequent 3 years of normal rainfall (2008-2010) under grazed and nongrazed conditions. Aboveground biomass and number of shoots were surveyed annually for each species. Nitrogen addition increased grassland productivity after drought irrespective of the grazing regime. The increase in grassland productivity was associated with an increase in the size of an annual, Salsola collina, under grazed conditions, and with an increase in shoot emergence of a perennial, Artemisia adamsii, under nongrazed conditions. The addition of low N content simulating N deposition around the study area by the year 2050 did not significantly increase grassland productivity. Our results suggest that increasing N deposition can enhance grassland recovery after a drought even in arid environments, such as the Mongolian steppe. This enhancement may be accompanied by a loss of grassland quality caused by an increase in the unpalatable species A. adamsii and largely depends on future human activities and the consequent deposition of N in Mongolia. PMID:22584584

Kinugasa, Toshihiko; Tsunekawa, Atsushi; Shinoda, Masato

2012-11-01

316

ORIGINAL PAPER Sperm morphology, swimming velocity, and longevity  

E-print Network

and sperm longevity in the house sparrow Passer domesticus. Sperm velocity was found to be correlated to maximize their fertilization success in a context of sperm competition. Keywords Passer domesticus . SpermORIGINAL PAPER Sperm morphology, swimming velocity, and longevity in the house sparrow Passer

Richner, Heinz

317

MINLP optimisation model for increased power production in small-scale CHP plants  

Microsoft Academic Search

In this work we present a mixed integer nonlinear programming (MINLP) model for increasing the power production in small-scale (1–20MWe) CHP plants based on a steam Rankine process and using biomass fuels. Changes that could increase the power production in these plants are, for instance, a steam reheater, a feed water preheater, a two-stage district heat exchanger, and a fuel

Tuula Savola; Carl-Johan Fogelholm

2007-01-01

318

The land potential knowledge system (LandPKS): Increasing land productivity and resilience  

Technology Transfer Automated Retrieval System (TEKTRAN)

Africa must significantly increase agricultural production to meet the needs of a growing population. Current efforts focus on intensifying production on currently used lands and expanding to un- or under-utilized lands. The success of both strategies requires understanding the land’s potential prod...

319

By Robert G. Reese, Jr. In 1995, total domestic mine production of silver increased  

E-print Network

1 SILVER By Robert G. Reese, Jr. In 1995, total domestic mine production of silver increased for the first time since 1990. About 83 mines in 17 States produced silver during the year. In descending order-fourths of the production. The 13 largest mines each produced more than 30 metric tons of silver and accounted for 79

320

“OMICS” of Human Sperm: Profiling Protein Phosphatases  

PubMed Central

Abstract Phosphorylation is a major regulatory mechanism in eukaryotic cells performed by the concerted actions of kinases and phosphatases (PPs). Protein phosphorylation has long been relevant to sperm physiology, from acquisition of motility in the epididymis to capacitation in the female reproductive tract. While the precise kinases involved in the regulation of sperm phosphorylation have been studied for decades, the PPs have only recently received research interest. Tyrosine phosphorylation was first implicated in the regulation of several sperm-related functions, from capacitation to oocyte binding. Only afterwards, in 1996, the inhibition of the serine/threonine-PP phosphoprotein phosphatase 1 (PPP1) by okadaic acid and calyculin-A was shown to initiate motility in caput epididymal sperm. Today, the current mechanisms of sperm motility acquisition based on PPP1 and its regulators are still far from being fully understood. PPP1CC2, specifically expressed in mammalian sperm, has been considered to be the only sperm-specific serine/threonine-PP, while other PPP1 isoforms were thought to be absent from sperm. This article examines the “Omics” of human sperm, and reports, for the first time, the identification of three new serine/threonine-protein PPs, PPP1CB, PPP4C, and PPP6C, in human sperm, together with two tyrosine-PPs, MKP1 and PTP1C. We specifically localized in sperm PPP1CB and PPP1CC2 from the PPP1 subfamily, and PPP2CA, PPP4C, and PPP6C from the PPP2 subfamily of the serine/threonine-PPs. A semi-quantitative analysis was performed to determine the various PPs' differential expression in sperm head and tail. These findings contribute to a comprehensive understanding of human sperm PPs, and warrant further research for their clinical and therapeutic significance. PMID:23895272

Ferreira, Mónica; Pelech, Steven; Vieira, Sandra; Rebelo, Sandra; Korrodi-Gregorio, Luís; Sousa, Mário; Barros, Alberto; Silva, Vladimiro; da Cruz e Silva, Odete A. B.; da Cruz e Silva, Edgar F.

2013-01-01

321

Dietary Fish Oil Can Change Sperm Parameters and Fatty Acid Profiles of Ram Sperm during Oil Consumption Period and after Removal of Oil Source  

PubMed Central

Objective The effects of dietary fish oil on semen quality and sperm fatty acid profiles during consumption of n-3 fatty acids as well as the persistency of fatty acids in ram’s sperm after removing dietary oil from the diet were investigated. Materials and Methods In this experimental study, we randomly assigned 9 Zandi rams to two groups (isoenergetic and isonitrogenous diets): control (CTR; n=5) and fish oil (FO; n=4) for 70 days with a constant level of vitamin E in both groups. Semen was collected at the first week and at the last week of the feeding period (phase 1). After the feeding period, all rams were fed a conventional diet and semen samples were collected one and two months after removal of FO (phase 2). The sperm parameters and fatty acid profiles were measured by computer assisted semen analyzer (CASA) and gas chromatography (GC), respectively. The completely randomized design was used and data were analyzed with SPSS version 16. Results Dietary FO had significant positive effects on all sperm quality and quantity parameters compared with the CTR during the feeding period (p<0.05). The positive effects of FO on sperm concentration and total sperm output were observed at one and two months after removal of FO (p<0.05), whereas other sperm parameters were unaffected. Before feeding, C14 (myristic acid), C16 (palmitic acid), C18 (stearic acid), C18:1 (oleic acid) and C22:6 (docosahexaenoic acid: DHA) were the primary sperm FA. FO in the diet increased sperm DHA, C14:0 and C18:0 during the feeding period (p<0.05). Conclusion The present study showed not only manipulation of ram sperm fatty acid profiles by dietary FO and sperm parameters during the feeding period, but also the persistency of unique effects of dietary omega-3 fatty acids up to two months following its removal from the diet. Also, we recommend that sperm fatty acid profiles should be comprehensively analyzed and monitored. PMID:24611147

Alizadeh, AliReza; Esmaeili, Vahid; Shahverdi, Abdolhossein; Rashidi, Ladan

2014-01-01

322

Direct human influence on atmospheric CO2 seasonality from increased cropland productivity  

NASA Astrophysics Data System (ADS)

Ground- and aircraft-based measurements show that the seasonal amplitude of Northern Hemisphere atmospheric carbon dioxide (CO2) concentrations has increased by as much as 50 per cent over the past 50 years. This increase has been linked to changes in temperate, boreal and arctic ecosystem properties and processes such as enhanced photosynthesis, increased heterotrophic respiration, and expansion of woody vegetation. However, the precise causal mechanisms behind the observed changes in atmospheric CO2 seasonality remain unclear. Here we use production statistics and a carbon accounting model to show that increases in agricultural productivity, which have been largely overlooked in previous investigations, explain as much as a quarter of the observed changes in atmospheric CO2 seasonality. Specifically, Northern Hemisphere extratropical maize, wheat, rice, and soybean production grew by 240 per cent between 1961 and 2008, thereby increasing the amount of net carbon uptake by croplands during the Northern Hemisphere growing season by 0.33 petagrams. Maize alone accounts for two-thirds of this change, owing mostly to agricultural intensification within concentrated production zones in the midwestern United States and northern China. Maize, wheat, rice, and soybeans account for about 68 per cent of extratropical dry biomass production, so it is likely that the total impact of increased agricultural production exceeds the amount quantified here.

Gray, Josh M.; Frolking, Steve; Kort, Eric A.; Ray, Deepak K.; Kucharik, Christopher J.; Ramankutty, Navin; Friedl, Mark A.

2014-11-01

323

Direct human influence on atmospheric CO2 seasonality from increased cropland productivity.  

PubMed

Ground- and aircraft-based measurements show that the seasonal amplitude of Northern Hemisphere atmospheric carbon dioxide (CO2) concentrations has increased by as much as 50 per cent over the past 50 years. This increase has been linked to changes in temperate, boreal and arctic ecosystem properties and processes such as enhanced photosynthesis, increased heterotrophic respiration, and expansion of woody vegetation. However, the precise causal mechanisms behind the observed changes in atmospheric CO2 seasonality remain unclear. Here we use production statistics and a carbon accounting model to show that increases in agricultural productivity, which have been largely overlooked in previous investigations, explain as much as a quarter of the observed changes in atmospheric CO2 seasonality. Specifically, Northern Hemisphere extratropical maize, wheat, rice, and soybean production grew by 240 per cent between 1961 and 2008, thereby increasing the amount of net carbon uptake by croplands during the Northern Hemisphere growing season by 0.33 petagrams. Maize alone accounts for two-thirds of this change, owing mostly to agricultural intensification within concentrated production zones in the midwestern United States and northern China. Maize, wheat, rice, and soybeans account for about 68 per cent of extratropical dry biomass production, so it is likely that the total impact of increased agricultural production exceeds the amount quantified here. PMID:25409830

Gray, Josh M; Frolking, Steve; Kort, Eric A; Ray, Deepak K; Kucharik, Christopher J; Ramankutty, Navin; Friedl, Mark A

2014-11-20

324

Dynamics of sperm DNA fragmentation in domestic animals II. The stallion.  

PubMed

The mixed success of equine artificial insemination programs using chilled and frozen-thawed semen is most likely associated with the variable response of the sperm cell to the preservation process and the fact that stallions are not selected on the basis of reproductive performance. We propose that the traditional indicators of sperm viability do not fully account for male factor infertility in the stallion and that knowledge of sperm DNA damage in the original semen sample and during semen processing may provide a more informed explanation of an individual stallion's reproductive potential. This study reports on the validation of a sperm DNA fragmentation test based on the sperm chromatin dispersion test (SCD) for stallion spermatozoa and on its application to semen that was chilled (4 degrees C; n=10) or frozen-thawed (n=13). Semen samples were collected by artificial vagina and the proportion of sperm with fragmented DNA determined. Seminal plasma was then removed by centrifugation and the sperm pellet re-suspended in commercial extenders prior to being chilled or cryopreserved using standard industry protocols. Chilled semen was cooled slowly to 4 degrees C and stored for 1h before commencing the analysis; cryopreserved semen was thawed and immediately analyzed. Following chilling or cryopreservation, the semen samples were incubated at 37 degrees C and analyzed for SCD after 0, 4, 6, 24 and 48 h storage. The results of this investigation revealed that there was no significant difference in the sperm DNA fragmentation index (sDFI) of sperm evaluated initially after collection compared to those tested immediately after chilling or cryopreservation. However, within 1h of incubation at 37 degrees C, both chilled and frozen-thawed spermatozoa showed a significant increase in the proportion of sDFI; after 6h the sDFI had increased to over 50% and by 48 h, almost 100% of the sperm showed DNA damage. While the sDFI of individual stallions at equivalent times of incubation was variable, an analysis of the rate of change of sDFI revealed no difference between stallions or the way in which the semen was preserved. In terms of sperm DNA fragmentation dynamics, the highest intensity of sperm DNA damage occurred in the first 6h of incubation. We suggest that the SCD test can be used as a routine assessment tool for the development and refinement of preservation protocols designed to reduce stallion sperm DNA damage. PMID:17919715

López-Fernández, C; Crespo, F; Arroyo, F; Fernández, J L; Arana, P; Johnston, S D; Gosálvez, J

2007-12-01

325

Sperm investment in male meadow voles is affected by the condition of the nearby male conspecifics  

PubMed Central

Sperm competition occurs when 2 or more males copulate with a particular female during the same reproductive cycle, and their sperm compete to fertilize the female's available eggs. One strategy that male voles use to assess the risk and intensity of sperm competition involves responding to the presence of scent marks of conspecific males found near a sexually receptive female. Previously, we have shown that if a male vole copulated with a female while he was in the presence of the odors of another male he increased his sperm investment relative to his investment if another male's odors were not present. The aim of the present study was to test the hypothesis that males assess differences in the relative quality of competing males and adjust their sperm investment accordingly. We did so by allowing males to copulate when they were exposed to the scent mark of a 24-h food-deprived male (low-quality male) or the scent mark of a male that was not food deprived (high-quality male). The data indicate that male meadow voles did not increase their sperm investment during copulation when exposed to the scent mark of a food-deprived male but did so when they were exposed to the scent mark of a male that was not food deprived. The results support the hypothesis that male voles are able to adjust sperm investment when they encounter the scent marks of males that differ in quality. PMID:19529815

delBarco-Trillo, Javier; Ferkin, Michael H.

2008-01-01

326

Identification of phosphoproteins coupled to initiation of motility in live epididymal mouse sperm  

NASA Technical Reports Server (NTRS)

A method for collecting live immotile cauda epididymal mouse sperm that initiate motility by dilution into an activation buffer is described. Sperm in collection buffer showed low percent motility (MOT) and population progression (PRG) that increased 10-fold and 9-fold, respectively, during the first 2 min after dilution into activation buffer. Western phosphoserine (pS), phosphothreonine (pT), and phosphotyrosine (pY) analysis revealed a 120 kDa protein that markedly increased in pT content during initiation of motility and may be related to FP130, the motility-coupled axonemal protein of sea urchin sperm. A prominent 82 kDa protein that was pS and pT-phosphorylated in immotile and motile sperm is likely the fibrous sheath component AKAP82 that is phosphorylated during spermatogenesis. Analysis of live human sperm also identified a prominent 120 kDa pT protein. Thus it appears that phosphorylation of FP130 and related 120 kDa proteins in mouse, and perhaps human sperm, represent common targets during motility initiation in sperm. Copyright 1998 Academic Press.

Tash, J. S.; Bracho, G. E.

1998-01-01

327

Dibromoacetic Acid Affects Reproductive Competence and Sperm Quality in the Male Rat  

Microsoft Academic Search

Dibromoacetic Acid Affects Reproductive Competence and Sperm Quality in the Male Rat. Linder, R. E., Klinefelter, G. R., Strader, L, F., Narotsky, M. G., Suarez, J. D., Roberts, N. L, and Perreault, S. D. (1995). Fundam. Appl. Toxicol. 28, 9-17.Recently, we demonstrated with short-duration tests that dibromoacetic acid (DBAA), a commonly occurring by-product of water disinfection, alters sperm morphology and

Ralph E. Linder; Gary R. Klinefelter; Lillian F. Strader; Michael G. Narotsky; Juan D. Suarez; Naomi L. Roberts; Sally D. Perreault

1995-01-01

328

Osmotic tolerance of avian spermatozoa: influence of time, temperature, cryoprotectant and membrane ion pump function on sperm viability.  

PubMed

Potential factors influencing sperm survival under hypertonic conditions were evaluated in the Sandhill crane (Grus canadensis) and turkey (Meleagridis gallopavo). Sperm osmotolerance (300-3000 mOsm/kg) was evaluated after: (1) equilibration times of 2, 10, 45 and 60 min at 4 degrees C versus 21 degrees C; (2) pre-equilibrating with dimethylacetamide (DMA) or dimethylsulfoxide (Me2SO) at either 4 degrees C or 21 degrees C; and (3) inhibition of the Na+/K+ and the Na+/H+ antiporter membrane ionic pumps. Sperm viability was assessed using the eosin-nigrosin live/dead stain. Species-specific differences occurred in response to hypertonic conditions with crane sperm remaining viable under extreme hypertonicity (3000 mOsm/kg), whereas turkey sperm viability was compromised with only slightly hypertonic (500 mOsm/kg) conditions. The timing of spermolysis under hypertonic conditions was also species-specific, with a shorter interval for turkey (2 min) than crane (10 min) sperm. Turkey sperm osmotolerance was slightly improved by lowering the incubation temperature from 21 to 4 degrees C. Pre-equilibrating sperm with DMA reduced the incidence of hypertonic spermolysis only in the crane, at both room and refrigeration temperature. Inhibiting the Na+/K+ and the Na+/H+ antiporter membrane ion pumps did not impair resistance of crane and turkey spermatozoa to hypertonic stress; pump inhibition actually increased turkey sperm survival compared to control sperm. Results demonstrate marked species specificity in osmotolerance between crane and turkey sperm, as well as in the way temperature and time of exposure affect sperm survival under hypertonic conditions. Differences are independent of the role of osmotic pumps in these species. PMID:18005955

Blanco, Juan M; Long, Julie A; Gee, George; Donoghue, Ann M; Wildt, David E

2008-02-01

329

Osmotic tolerance of avian spermatozoa: Influence of time, temperature, cryoprotectant and membrane ion pump function on sperm viability  

USGS Publications Warehouse

Potential factors influencing sperm survival under hypertonic conditions were evaluated in the Sandhill crane (Grus canadensis) and turkey (Meleagridis gallopavo). Sperm osmotolerance (300-3000 mOsm/kg) was evaluated after: (1) equilibration times of 2, 10, 45 and 60 min at 4 ?C versus 21 ?C; (2) pre-equilibrating with dimethylacetamide (DMA) or dimethylsulfoxide (Me2SO) at either 4 ?C or 21 ?C; and (3) inhibition of the Na+/K+ and the Na+/H+ antiporter membrane ionic pumps. Sperm viability was assessed using the eosin-nigrosin live/dead stain. Species-specific differences occurred in response to hypertonic conditions with crane sperm remaining viable under extreme hypertonicity (3000 mOsm/kg), whereas turkey sperm viability was compromised with only slightly hypertonic (500 mOsm/kg) conditions. The timing of spermolysis under hypertonic conditions was also species-specific, with a shorter interval for turkey (2 min) than crane (10 min) sperm. Turkey sperm osmotolerance was slightly improved by lowering the incubation temperature from 21 to 4 ?C. Pre-equilibrating sperm with DMA reduced the incidence of hypertonic spermolysis only in the crane, at both room and refrigeration temperature. Inhibiting the Na+/K+ and the Na+/H+ antiporter membrane ion pumps did not impair resistance of crane and turkey spermatozoa to hypertonic stress; pump inhibition actually increased turkey sperm survival compared to control sperm. Results demonstrate marked species specificity in osmotolerance between crane and turkey sperm, as well as in the way temperature and time of exposure affect sperm survival under hypertonic conditions. Differences are independent of the role of osmotic pumps in these species.

Blanco, J.M.; Long, J.A.; Gee, G.; Donoghue, A.M.; Wildt, D.E.

2008-01-01

330

Increasing corn for biofuel production reduces biocontrol services in agricultural landscapes  

E-print Network

Increasing corn for biofuel production reduces biocontrol services in agricultural landscapes November 5, 2008 (received for review May 22, 2008) Increased demand for corn grain as an ethanol feedstock is altering U.S. agricultural landscapes and the ecosystem services they pro- vide. From 2006 to 2007, corn

Landis, Doug

331

Productivity of Ospreys in Connecticut-Long Island Increases as DDE Residues Decline  

Microsoft Academic Search

Nesting success of ospreys (Pandion haliaetus) breeding in the Connecticut-Long Island area has increased since 1973 and is now approaching the levels recorded prior to the 1950's. Simultaneously, DDE and dieldrin residues have declined in unhatched eggs. Levels of polychorinated biphenyls have shown no changes over the period 1969 to 1976. The increase in productivity is attributed primarily to lower

Paul R. Spitzer; Robert W. Risebrough; Wayman Walker II; Robert Hernandez; Alan Poole; Dennis Puleston; Ian C. T. Nisbet

1978-01-01

332

Expiratory resistive loaded breathing in humans increases fluctuations of force production in submaximal isometric quadriceps contractions  

Microsoft Academic Search

This study demonstrated that expiratory resistive loading (ERL) induced an increase in force fluctuation during a unilateral, submaximal isometric contraction of the non-dominant left vastus lateralis (VL), but did not effect force fluctuation during complex bilateral contractions. The increase in force fluctuation in the unilateral left VL contraction during ERL was not accompanied by alterations of average force production, motor

Duncan L. Turner

2002-01-01

333

Does Audiovisual Congruency in Advertisements Increase Persuasion? The Role of Cultural Music and Products  

Microsoft Academic Search

Given increasing advertisement clutter, advertisers are increasingly trying unconventional means to attract consumers' attention. One such method involves the use of incongruent ads, which are believed to attract viewers' attention. This research was conducted to ascertain the impact of audiovisual congruency in ads and the moderating role of product involvement on three facets of consumer response: attention to the ad,

Ashok K. Lalwani; May O. Lwin; Pee Beng Ling

2009-01-01

334

Sperm in peritoneal fluid from a man with ascites: a case report  

PubMed Central

Introduction The finding of sperm in body fluids such as peritoneal fluid is unusual, and has been mostly described in female patients. Case presentation We are reporting the case of a 52-year-old man who presented with complaints of increased abdominal girth, weight gain and epigastric pain. He was subsequently found to have spontaneous bacterial peritonitis and sperm in the peritoneal fluid. We describe the laboratory findings and clinical course in this patient. Conclusion To our knowledge, this is the first report of sperm in peritoneal fluid in a male patient. PMID:19946502

2009-01-01

335

Extraction of soluble substances from organic solid municipal waste to increase methane production.  

PubMed

This work deals with the analysis of the methane production from Mexico City's urban organic wastes after separating soluble from suspended substances. Water was used to extract soluble substances under three different water to waste ratios and after three extraction procedures. Methane production was measured at 35°C during 21days using a commercial methane potential testing device. Results indicate that volatile solids extraction increases with dilution rate to a maximum of 40% at 20°C and to 43% at 93°C. The extracts methane production increases with the dilution rate as a result of enhanced dissolved solids extraction. The combined (extract and bagasse) methane production reached, in 6days, 66% of the total methane produced in 21days. The highest methane production rates were measured during the first six days. PMID:25190296

Campuzano, Rosalinda; González-Martínez, Simón

2015-02-01

336

Potential Changes in Rat Spermatogenesis and Sperm Parameters after Inhalation of Boswellia papyrifera and Boswellia carterii Incense  

PubMed Central

In this study the effect of Boswellia papyrifera (B. papyrifera) and Boswellia carterii (B. carterii) smoke exposure on spermatogenesis and sperm parameters in male albino rats was investigated. Rats (n = 11) were exposed daily in smoking chambers to smoke emanated by burning 4 g each of either B. papyrifera or B. carterii for 48 days. At the end of exposure duration rats were killed, and the testes were excised and analysed for histopathological and ultrastructural changes. Sperm analysis including total sperm count, motility, velocity and relative percentage of abnormal sperms were recorded. Rats exposed to B. papyrifera and B. carterii showed significant disturbances in spermatogenetic patterns and changes in sperm kinetics compared to unexposed rats. Atrophied seminiferous tubules with dynamic changes were also noticed. The boundaries of intercellular and intracellular vacuoles were seen in the Sertoli cells. Furthermore, in spermatids acrosomal vesicles were not fully formed. Degenerating spermatids were devoid of their nuclear membrane with electron dense matrix and vacuolization. Structural changes in Leydig cells were observed. Sperm analysis in exposed rats exhibited significant decrease in the sperm count, motility, speed and an increase in sperm anomalies when compare to controls. These findings demonstrate that the B. papyrifera and B. carterii smoke affects the process of spermatogenesis and sperm parameters and indicate the detrimental effects of these incense materials on human reproductive system. PMID:23449005

Ahmed, Mukhtar; Al-Daghri, Nasser; Alokail, Majed S.; Hussain, Tajamul

2013-01-01

337

Potential changes in rat spermatogenesis and sperm parameters after inhalation of Boswellia papyrifera and Boswellia carterii incense.  

PubMed

In this study the effect of Boswellia papyrifera (B. papyrifera) and Boswellia carterii (B. carterii) smoke exposure on spermatogenesis and sperm parameters in male albino rats was investigated. Rats (n = 11) were exposed daily in smoking chambers to smoke emanated by burning 4 g each of either B. papyrifera or B. carterii for 48 days. At the end of exposure duration rats were killed, and the testes were excised and analysed for histopathological and ultrastructural changes. Sperm analysis including total sperm count, motility, velocity and relative percentage of abnormal sperms were recorded. Rats exposed to B. papyrifera and B. carterii showed significant disturbances in spermatogenetic patterns and changes in sperm kinetics compared to unexposed rats. Atrophied seminiferous tubules with dynamic changes were also noticed. The boundaries of intercellular and intracellular vacuoles were seen in the Sertoli cells. Furthermore, in spermatids acrosomal vesicles were not fully formed. Degenerating spermatids were devoid of their nuclear membrane with electron dense matrix and vacuolization. Structural changes in Leydig cells were observed. Sperm analysis in exposed rats exhibited significant decrease in the sperm count, motility, speed and an increase in sperm anomalies when compare to controls. These findings demonstrate that the B. papyrifera and B. carterii smoke affects the process of spermatogenesis and sperm parameters and indicate the detrimental effects of these incense materials on human reproductive system. PMID:23449005

Ahmed, Mukhtar; Al-Daghri, Nasser; Alokail, Majed S; Hussain, Tajamul

2013-03-01

338

Heavy ion radiation can promote greater motility and enolase protein expression in ram sperm in in vitro liquid storage.  

PubMed

The aim of the study was to determine the effects of heavy ion radiation (HIR) on ram sperm quality during 24h of in vitro liquid storage at 15°C, and identify the most appropriate dose which did not injure, but actually improved sperm quality and confirmed the relationship between highly expressed enolase and ram sperm quality during storage in vitro. Six Dorset ram (Ovis aries) semen pools from five mature and healthy rams were each divided into seven experimental groups with different doses of HIR (0, 0.05, 0.1, 0.2, 0.3, 0.4, and 0.5Gy) under the same experimental conditions. Sperm motility, viability, ATP content, and the gene and protein expression of enolase were measured at 24h of storage. Irradiated semen which had been stored for 24h, retained not only greater sperm motility, viability, and ATP content, but had greater enolase protein expression. This was evidenced by increased amounts of mRNA for this enzyme and amount of enolase protein as compared with semen from control rams, especially for the 0.1Gy group (P<0.001). These results indicate that HIR can promote enhanced motility and viability during in vitro liquid storage, and the 0.1Gy may be a suitable dose for improving sperm quality. Greater amounts of enolase and ATP content may results from enhanced sperm glycolysis by HIR. HIR enhances sperm glycolysis to generate sufficient ATP for maintaining sperm motility during storage. PMID:25018045

He, Yuxuan; Li, Hongyan; He, Jianhua; Zhao, Xingxu

2014-08-01

339

Freeze-drying of mammalian sperm.  

PubMed

Long-term preservation of mammalian sperm at suprazero temperatures is desired to save storage and space costs as well as to facilitate transport of preserved samples. This can be accomplished by the freeze-drying of sperm samples. Although freeze-drying results in immotile and membrane-compromised sperm, intracytoplasmic sperm injection (ICSI) can be used to introduce such an immotile sperm into an oocyte and thus start the fertilization process. So far, it has been shown that improved freeze-drying protocols preserve chromosomal integrity and oocyte-activating factor(s) at 4 °C for several years and at ambient temperature for approximately 1 month, which permits shipping freeze-dried samples at ambient temperature. This chapter concisely reviews freeze-drying of mammalian sperm first and then presents a simple freeze-drying protocol. PMID:25428025

Keskintepe, Levent; Eroglu, Ali

2015-01-01

340

Nuclear microscopy of sperm cell elemental structure  

SciTech Connect

Theories suggest there is a link between protamine concentrations in individual sperm and male fertility. Previously, biochemical analyses have used pooled samples containing millions of sperm to determine protamine concentrations. These methods have not been able to determine what percentage of morphologically normal sperm are biochemically defective and potentially infertile. Nuclear microscopy has been utilized to measure elemental profiles at the single sperm level. By measuring the amount of phosphorus and sulfur, the total DNA and protamine content in individual sperm from fertile bull and mouse semen have been determined. These values agree with results obtained from other biochemical analyses. Nuclear microscopy shows promise for measuring elemental profiles in the chromatin of individual sperm. The technique may be able to resolve theories regarding the importance of protamines to male fertility and identify biochemical defects responsible for certain types of male infertility.

Bench, G.S.; Balhorn, R.; Friz, A.M.; Freeman, S.P.H.T.

1994-09-28

341

Nuclear microscopy of sperm cell elemental structure  

NASA Astrophysics Data System (ADS)

Theories suggest there is a link between protamine concentrations in individual sperm and male fertility. Previously, biochemical analyses have used pooled samples containing millions of sperm to determine protamine concentrations. These methods have not been able to determine what percentage of morphologically normal sperm are biochemically defective and potentially infertile. Nuclear microscopy has been utilized to measure elemental profiles at the single sperm level. By measuring the amount of phosphorus and sulfur, the total DNA and protamine content in individual sperm from fertile bull and mouse semen have been determined. These values agree with results obtained from other biochemical analyses. Nuclear microscopy shows promise for measuring elemental profiles in the chromatin of individual sperm. The technique may be able to resolve theories regarding the importance of protamines to male fertility and identify biochemical defects responsible for certain types of male infertility.

Bench, Graham S.; Balhorn, Rod; Friz, Alexander M.

1995-05-01

342

Lipid profiles of sperm and seminal plasma from boars having normal or low sperm motility.  

PubMed

Sperm plasma membrane lipids have an important role to play in determining membrane fluidity and sperm motility. The objective of the present study was to determine whether there are differences in the lipid and fatty acid (FA) composition of boar sperm and seminal plasma in the ejaculates of boars having different sperm motilities. Semen was collected from two groups of boars having normal (> 60%; n = 53) or low (< 60%; n = 53) motility sperm and the semen was evaluated for motility, morphology and vitality. The semen was then centrifuged to separate the sperm from the seminal plasma and both were kept at -20 °C until analyzed for lipid content and FA profile by gas chromatography. Total antioxidant status (TAS) of seminal plasma was determined using a commercial kit. There were differences (P ? 0.05) in sperm total lipids, cholesterol, saturated fatty acids (SFA), phospholipids, n-3 polyunsaturated fatty acids (PUFA), docosahexaenoic acid (DHA) and the ratio of n-6:n-3 PUFA between boars with normal and low motility sperm. Total lipids, cholesterol, phospholipids, PUFA, DHA and n-3 PUFA were positively correlated with sperm motility, viability, normal morphology and normal plasma membrane. In contrast, SFA and the ratio of n-6: n-3 PUFA were negatively correlated (P ? 0.05) with sperm motility, viability, normal morphology and normal plasma membranes. The TAS of seminal plasma from boars having normal motility sperm was higher (P ? 0.05) than that of boars having low motility sperm and TAS was positively correlated (P = 0.0001) with sperm motility, viability, normal morphology and normal plasma membranes. In summary, differences in sperm motility were related to n-3 PUFA content in the sperm plasma membrane and extracellular antioxidants in seminal plasma which protect sperm plasma membranes from lipid peroxidation during periods of oxidative stress. PMID:21167582

Am-in, N; Kirkwood, R N; Techakumphu, M; Tantasuparuk, W

2011-03-15

343

Pregnancy after intracytoplasmic sperm injection with sperm from a man with a 47,XXY Klinefelter's karyotype  

Microsoft Academic Search

Objective: To report the initiation of a pregnancy that was achieved by intracytoplasmic sperm injection (ICSI) with sperm from a patient with Klinefelter's syndrome.Design: Case report.Setting: University women's hospital IVF center.Patient(s): A couple with primary infertility and nonmosaic 47,XXY karyotype of the male partner.Intervention(s): Intracytoplasmic sperm injection after ovarian stimulation and transvaginal ultrasound-guided oocyte pick-up with sperm from a hypergonadotropic

Bernd Hinney; Martina Guttenbach; Michael Schmid; Wolfgang Engel; Hans Wilhelm Michelmann

1997-01-01

344

A Sterile Sperm Caste Protects Brother Fertile Sperm from Female-Mediated Death in Drosophila pseudoobscura  

Microsoft Academic Search

? C in 20 polypropylene bottles (57 3 132 mm) containing standard food medium (cornmeal, agar, and molasses) at a population size of w500 interbreeding adults. All individuals used were virgin and were 5 days old posteclosion, i.e., were reproductively mature (S1, S2). Sperm Counts Sperm viability was assessed by staining sperm samples with 1 ml of dilute LIVE\\/DEAD sperm

Luke Holman; Rhonda R. Snook

2008-01-01

345

Re-feeding food-deprived male meadow voles affects the sperm allocation of their rival males.  

PubMed

An individual's nutritional status affects the manner in which same- and opposite-sex conspecifics respond to that individual, which may affect their fitness. Male meadow voles, Microtus pennsylvanicus, increase their sperm allocation if they encounter the scent mark of an unfamiliar male that is not nutritionally challenged. If, however, the scent mark comes from a male that has been food deprived for 24 hours, stud male voles do not increase their sperm allocation. Food deprived males may be viewed as being lower quality and a reduced risk of sperm competition by rival males. We hypothesized that stud males in promiscuous mating systems tailor their sperm allocations depending on whether rival males have been food deprived and then re-fed. We predicted that newly re-fed males will be considered a strong risk of sperm competition because of the potentially high fitness and survival costs associated with food deprivation in males, and that they will cause stud males to increase their sperm allocation. Our results, however, showed that the recovery period from 24 hours of food deprivation was a relatively slow process. It took between 96 hours and 336 hours of re-feeding male scent donors that were food deprived for 24 hours to induce stud males to increase their sperm allocation to levels comparable to when scent donors were not food deprived. Stud male voles may be conserving the amount of sperm allocated until the male scent donors have recovered from food deprivation and subsequent re-feeding. PMID:23185098

Vaughn, Ashlee A; Delbarco-Trillo, Javier; Ferkin, Michael H

2012-12-01

346

Flow cytometry analysis reveals a decrease in intracellular sodium during sperm capacitation  

PubMed Central

Mammalian sperm require time in the female tract in order to be able to fertilize an egg. The physiological changes that render the sperm able to fertilize are known as capacitation. Capacitation is associated with an increase in intracellular pH, an increase in intracellular calcium and phosphorylation of different proteins. This process is also accompanied by the hyperpolarization of the sperm plasma membrane potential. Recently, we presented evidence showing that epithelial Na+ channels (ENaC) are present in mature sperm and that ENaCs are blocked during capacitation. In the present work, we used flow cytometry to analyze changes in intracellular Na+ concentration ([Na+]i) during capacitation in individual cells. Our results indicate that capacitated sperm have lower Na+ concentrations. Using sperm with green fluorescent protein in their acrosomes, it was shown that the lower [Na+]i concentration only occurs in sperm having intact acrosomes. ENaC inhibition has been shown in other cell types to depend on the activation of cystic fibrosis transmembrane conductance regulator (CFTR). In non-capacitated sperm, amiloride, an ENaC inhibitor, and genistein, a CFTR activator, caused a decrease in [Na+]i, suggesting that also in these cells [Na+]i is dependent on the crosstalk between ENaC and CFTR. In addition, PKA inhibition blocked [Na+]i decrease in capacitated sperm. Altogether, these data are consistent with the hypothesis that the capacitation-associated hyperpolarization involves a decrease in [Na+]i mediated by inhibition of ENaC and regulated by PKA through activation of CFTR channels. PMID:22302997

Escoffier, Jessica; Krapf, Dario; Navarrete, Felipe; Darszon, Alberto; Visconti, Pablo E.

2012-01-01

347

Rimonabant (SR141716) induces metabolism and acquisition of fertilizing ability in human sperm  

PubMed Central

Background and purpose: The endocannabinoid system and the cannabinoid CB1 receptor have been identified in human sperm, and it is well known that endocannabinoids have pronounced adverse effects on male and female reproduction. In order to elucidate further the pathophysiological role of the endocannabinoid system in male fertility, we investigated the activity of the CB1 receptor antagonist rimonabant (SR141716) on the fertilizing ability of human sperm. Experimental approach: We evaluated in vitro the effects of rimonabant on motility, survival, capacitation, acrosin activity and metabolism of human sperm. Particularly, capacitation was studied by using three different approaches: intracellular free Ca2+ content assay, cholesterol efflux assay and protein tyrosine phosphorylation analysis. Key results: Rimonabant significantly increased sperm motility and viability through the induction of pAkt and pBcl2, key proteins of cell survival and metabolism, and it induced acrosome reaction and capacitation as well. Rimonabant reduced the triglyceride content of sperm, while enhancing lipase and acyl-CoA dehydrogenase activities, implying an overall lipolytic action in these cells. Rimonabant also affected sperm glucose metabolism by decreasing phosphorylation of glycogen synthase kinase 3 and increasing glucose-6-phosphate dehydrogenase activity, suggesting a role in inducing sperm energy expenditure. Intriguingly, agonism at the CB1 receptor, with an anandamide analogue or a selective inhibitor of fatty acid amide hydrolase, produced opposing effects on human sperm functions. Conclusions and implications: Our data suggest that blockade of the CB1 receptor by rimonabant induces the acquisition of fertilizing ability and stimulates energy expenditure in human sperm. PMID:20067470

Aquila, S; Guido, C; Santoro, A; Gazzerro, P; Laezza, C; Baffa, MF; Andò, S; Bifulco, M

2010-01-01

348

Climate-driven increases in global terrestrial net primary production from 1982 to 1999.  

PubMed

Recent climatic changes have enhanced plant growth in northern mid-latitudes and high latitudes. However, a comprehensive analysis of the impact of global climatic changes on vegetation productivity has not before been expressed in the context of variable limiting factors to plant growth. We present a global investigation of vegetation responses to climatic changes by analyzing 18 years (1982 to 1999) of both climatic data and satellite observations of vegetation activity. Our results indicate that global changes in climate have eased several critical climatic constraints to plant growth, such that net primary production increased 6% (3.4 petagrams of carbon over 18 years) globally. The largest increase was in tropical ecosystems. Amazon rain forests accounted for 42% of the global increase in net primary production, owing mainly to decreased cloud cover and the resulting increase in solar radiation. PMID:12791990

Nemani, Ramakrishna R; Keeling, Charles D; Hashimoto, Hirofumi; Jolly, William M; Piper, Stephen C; Tucker, Compton J; Myneni, Ranga B; Running, Steven W

2003-06-01

349

Semen Quality and Sperm Function Loss by Hypercholesterolemic Diet Was Recovered by Addition of Olive Oil to Diet in Rabbit  

PubMed Central

Fat increment (0.05% cholesterol, chol) in standard diet promoted a significant increase in serum and sperm membrane chol, which ultimately altered membrane-coupled sperm specific functions: osmotic resistance, acrosomal reaction, and sperm capacitation in White New Zealand rabbits. These changes were also associated with a reduction in motility percentage and appearance of abnormal sperm morphology. The present study was carried out to evaluate the effect of dietary olive oil (OO, 7% v/w) administration to several male hypercholesterolemic rabbits (hypercholesterolemic rabbits, HCR) with altered fertility parameters. These HCR males were achieved by feeding normal rabbits with a high-fat diet (0.05% chol). HCR were associated with a modest non-significant increase in body weight (standard diet, 4.08±0.17 Kg, versus high-fat diet, 4.37±0.24 Kg). Hypercholesterolemic rabbits presented a marked decrease in semen volume, sperm cell count, and percentage of sperm motility, associated with a significant increase in sperm cell abnormalities. Moreover, sperm capacitation measured by the characteristic phosphorylated protein pattern in and induced acrosomal reaction were also altered suggesting sperm dysfunction. However, the administration of OO (for 16 weeks) to rabbits that were fed with 50% of the high-fat diet normalized serum chol. Curiously, OO supply succeeded to attenuate the seminal and sperm alterations observed in HCR group. Administration of OO alone did not cause any significant changes in above mentioned parameters. These data suggest that OO administration to HCR male rabbits recovers the loss of semen quality and sperm functionality. PMID:23326331

Romero, Aida A.; Funes, Abi K.; Cid-Barria, Macarena; Cabrillana, María E.; Monclus, María A.; Simón, Layla; Vicenti, Amanda E.; Fornés, Miguel W.

2013-01-01

350

Cryopreservation of domestic animal sperm cells  

Microsoft Academic Search

Sperm cells are the endpoint of male spermatogenesis and have particular anatomic and metabolic features. Sperm cryopreservation\\u000a and storage currently require liquid nitrogen or ultralow refrigeration methods for long or short term storage, which requires\\u000a routine maintenance and extensive space requirements. Conserving sperms have several purposes such as artificial reproductive\\u000a technologies (ART), species conservation and clinical medicine. The combinations of

J. P. Barbas; R. D. Mascarenhas

2009-01-01

351

Airborne sperm of Conocephalum conicum (Conocephalaceae)  

Microsoft Academic Search

We have obtained the first momentary photographs of sperms just as they are discharged from the antheridium of a liverwort,\\u000a Conocephalum conicum, and have succeeded in monitoring the airborne sperms of bryophytes under field conditions. Airborne sperm of liverworts\\u000a seems to be an effective strategy for raising the efficiency of fertilization between male and female plants separated in\\u000a a drought

Masaki Shimamura; Tomio Yamaguchi; Hironori Deguchi

2008-01-01

352

Cryopreservation of Sperm from Endangered Pallid Sturgeon  

Microsoft Academic Search

We sought to develop sperm cryopreservation methods for the pallid sturgeon Scaphirhynchus albus, a federally listed endangered species. Males were injected with synthetic luteinizing hormone releasing hormone at 50 ?g\\/kg of body weight. After 24 h, sperm were collected, diluted at a ratio of 1:4 (sperm : extender) with Hanks' balanced salt solution (HBSS; diluted to 100 milliosmoles\\/kg), and kept

William R. Wayman; Gregory L. Looney; Robert J. Holm; Terrence R. Tiersch

2008-01-01

353

Intracytoplasmic Sperm Injection Using DNA-Fragmented Sperm in Mice Negatively Affects Embryo-Derived Embryonic Stem Cells, Reduces the Fertility of Male Offspring and Induces Heritable Changes in Epialleles  

PubMed Central

Intracytoplasmic sperm injection (ICSI) in mice using DNA-fragmented sperm (DFS) has been linked to an increased risk of genetic and epigenetic abnormalities both in embryos and offspring. This study examines: whether embryonic stem cells (ESCs) derived from DFS-ICSI embryos reflect the abnormalities observed in the DFS-ICSI progeny; the effect of DFS-ICSI on male fertility; and whether DFS-ICSI induces epigenetic changes that lead to a modified heritable phenotype. DFS-ICSI-produced embryos showed a low potential to generate ESC lines. However, these lines had normal karyotype accompanied by early gene expression alterations, though a normal expression pattern was observed after several passages. The fertility of males in the DFS-ICSI and control groups was compared by mating test. Sperm quantity, vaginal plug and pregnancy rates were significantly lower for the DFS-ICSI-produced males compared to in vivo-produced mice, while the number of females showing resorptions was higher. The epigenetic effects of DFS-ICSI were assessed by analyzing the phenotype rendered by the Axin1Fu allele, a locus that is highly sensitive to epigenetic perturbations. Oocytes were injected with spermatozoa from Axin1Fu/+ mice and the DFS-ICSI-generated embryos were transferred to females. A significantly higher proportion of pups expressed the active kinky-tail epiallele in the DFS-ICSI group than the controls. In conclusion: 1) ESCs cannot be used as a model of DFS-ICSI; 2) DFS-ICSI reduces sperm production and fertility in the male progeny; and 3) DFS-ICSI affects the postnatal expression of a defined epigenetically sensitive allele and this modification may be inherited across generations. PMID:24743851

Fernández-González, Raúl; Laguna-Barraza, Ricardo; Pericuesta, Eva; Calero, Antonia; Ramírez, Miguel Ángel; Gutiérrez-Adán, Alfonso

2014-01-01

354

Sperm chemotaxis, fluid shear, and the evolution of sexual reproduction  

PubMed Central

Chemical communication is fundamental to sexual reproduction, but how sperm search for and find an egg remains enigmatic. For red abalone (Haliotis rufescens), a large marine snail, the relationship between chemical signaling and fluid motion largely determines fertilization success. Egg-derived attractant plumes are dynamic, changing their size and shape in response to unique combinations of physical and chemical environmental features. Attractant plumes that promote sexual reproduction, however, are limited to a precise set of hydrodynamic conditions. Performance-maximizing shears are those that most closely match flows in native spawning habitats. Under conditions in which reproductive success is chronically limited by sperm availability, gametes are under selection for mechanisms that increase sperm–egg encounter. Here, chemoattraction is found to provide a cheap evolutionary alternative for enhancing egg target size without enlarging cytoplasmic and/or cell volume. Because egg signaling and sperm response may be tuned to meet specific fluid-dynamic constraints, shear could act as a critical selective pressure that drives gamete evolution and determines fitness. PMID:21788487

Zimmer, Richard K.; Riffell, Jeffrey A.

2011-01-01

355

Increased Hepatic Glucose Production in Fetal Sheep With Intrauterine Growth Restriction Is Not Suppressed by Insulin  

PubMed Central

Intrauterine growth restriction (IUGR) increases the risk for metabolic disease and diabetes, although the developmental origins of this remain unclear. We measured glucose metabolism during basal and insulin clamp periods in a fetal sheep model of placental insufficiency and IUGR. Compared with control fetuses (CON), fetuses with IUGR had increased basal glucose production rates and hepatic PEPCK and glucose-6-phosphatase expression, which were not suppressed by insulin. In contrast, insulin significantly increased peripheral glucose utilization rates in CON and IUGR fetuses. Insulin robustly activated AKT, GSK3?, and forkhead box class O (FOXO)1 in CON and IUGR fetal livers. IUGR livers, however, had increased basal FOXO1 phosphorylation, nuclear FOXO1 expression, and Jun NH2-terminal kinase activation during hyperinsulinemia. Expression of peroxisome proliferator–activated receptor ? coactivator 1? and hepatocyte nuclear factor-4? were increased in IUGR livers during basal and insulin periods. Cortisol and norepinephrine concentrations were positively correlated with glucose production rates. Isolated IUGR hepatocytes maintained increased glucose production in culture. In summary, fetal sheep with IUGR have increased hepatic glucose production, which is not suppressed by insulin despite insulin sensitivity for peripheral glucose utilization. These data are consistent with a novel mechanism involving persistent transcriptional activation in the liver that seems to be unique in the fetus with IUGR. PMID:22933111

Thorn, Stephanie R.; Brown, Laura D.; Rozance, Paul J.; Hay, William W.; Friedman, Jacob E.

2013-01-01

356

Single layer centrifugation (SLC) improves sperm quality of cryopreserved Blanca-Celtibérica buck semen.  

PubMed

The aim of the present study was to evaluate the effect of sperm selection by means of single layer centrifugation (SLC) on sperm quality after cryopreservation, either when SLC is used before freezing or after thawing, using Blanca-Celtibérica buck semen collected by electroejaculation (EE). Ejaculates from six bucks were collected by EE and divided into two aliquots. One of them (unselected) was diluted with Biladyl(®) by the two-step method and frozen over nitrogen vapor. The other aliquot was selected by the SLC technique and subsequently frozen in the same way as the unselected samples (SLC before freezing). In a further treatment, two unselected straws were thawed and SLC was carried out (SLC after thawing). At thawing, sperm motility of all samples ((i) unselected; (ii) selected before freezing and (iii) selected after thawing) was evaluated by CASA. In addition, integrity of the plasma membrane, mitochondrial membrane potential, ROS production and DNA fragmentation index were assessed by flow cytometry. Most of the sperm parameters were improved (P?0.001) in samples selected by SLC after thawing in relation to unselected or selected by SLC before freezing. The percentage of progressive motile spermatozoa was greater (86%) for sperm samples selected after thawing compared with unselected (58%) or selected before freezing (54%). Moreover, percentages of spermatozoa with intact plasma membrane and spermatozoa with high mitochondrial membrane potential (hMMP) were also greater for sperm samples selected after thawing compared to sperm samples unselected or selected before freezing (spermatozoa with intact plasma membrane: 80% vs. 32% vs. 12%; spermatozoa with hMMP: 54% vs. 1% vs. 15%; respectively). Therefore, sperm quality after cryopreservation is improved in Blanca-Celtibérica buck ejaculates collected by EE when a sperm selection technique such as SLC is carried out after thawing. PMID:23084569

Jiménez-Rabadán, P; Morrell, J M; Johannisson, A; Ramón, M; García-Álvarez, O; Maroto-Morales, A; Alvaro-García, P J; Pérez-Guzmán, M D; Fernández-Santos, M R; Garde, J J; Soler, A J

2012-12-01

357

Improvement of Ram Sperm Cryopreservation Protocols Assessed by Sperm Quality Parameters and Heterogeneity Analysis  

Microsoft Academic Search

Semen cryopreservation processes generally decrease sperm quality and fertility rate, but this is highly dependent on the specific susceptibility of sperm cells to low temperatures. In order to study the effect of cooling, freezing, and thawing on ram spermatozoa, sperm viability (plasma membrane integrity), HOS test (hyposmotic swelling test), and individual motility were assessed in fresh, cooled, and frozen–thawed samples.

M. Ollero; R. Perez-Pe; T. Muiño-Blanco; J. A. Cebrian-Perez

1998-01-01

358

Cryopreservation of Sperm in Common Carp Cyprinus carpio: Sperm Motility and Hatching Success of Embryos  

Microsoft Academic Search

In this study, fish sperm cryopreservation methods were elaborated upon for ex situ conservation of nine strains of Bohemian common carp. Common carp sperm were diluted in Kurokura medium and chilled to 4°C and dimethyl sulfoxide was added. Cryotubes of sperm with media were then cooled from +4 to ?9°C at a rate of 4°C min?1 and then from ?9

Otomar Linhart; Marek Rodina; Jacky Cosson

2000-01-01

359

Sperm competition in a fish with external fertilization: the contribution of sperm number, speed and length  

E-print Network

Sperm competition in a fish with external fertilization: the contribution of sperm number, speed, and occurs in a range of animal taxa including amphibians, birds, fishes, insects and mammals (Birkhead). In externally fertilizing fishes, sperm competition ranges from near complete mate monopolization to large

Neff, Bryan D.

360

Sperm competition in a fish with external fertilization: the contribution of sperm number, speed and length  

Microsoft Academic Search

bluegill; fish; mechanism; raffle; speed; sperm competition; sperm number. Abstract The role of sperm number and quality in male competitiveness was investigated using in vitro fertilization experiments with bluegill (Lepomis macrochirus). Bluegill males use one of three mating tactics: 'sneakers', which streak spawn; 'satellites', which mimic females; and 'parentals', which are territorial. The in vitro experiments mimicked natural spawning by

J. A. STOLTZ; B. D. NEFF

2006-01-01

361

METHOD OF SPERM COLLECTION SIGNIFICANTLY INFLUENCES SPERM MOTION PARAMETERS FOLLOWING ETHANE DIMETHANESULPHONATE ADMINISTRATION IN THE RAT  

EPA Science Inventory

Sperm motion analysis following exposure to a reproductive toxicant is one means of evaluating the functional integrity of the testes and epididymis. n this study we sought to determine whether the method used to collect sperm from the proximal cauda epididymidis, where sperm are...

362

Seasonal dynamics of sperm morphometric subpopulations and its association with sperm quality parameters in ram ejaculates.  

PubMed

Sperm morphologic assessment is considered an irreplaceable part of standard laboratory routine analyses in the diagnosis of male fertility. Thus, in an attempt to quantify the effects of season on sperm morphology and its functional significance in relation to sperm quality parameters, sperm head morphometric traits were analyzed by using an objective computerized analysis combined with principal components analysis (PCA) cluster analysis to establish the relationship between the distribution of the subpopulations found and sperm quality in each season. There were slight variations on sperm motility and sperm membrane integrity indexes (P > 0.05). However, the mean values for sperm concentration substantially changed among seasons in all individuals studied (P < 0.01). There were significant differences in sperm morphometric parameters (P < 0.01) as well as in the distribution of morphometric subpopulations between seasons (P < 0.001). In conclusion, this study confirmed that there was an important seasonal effect on sperm morphometric traits. In addition, the distribution of these subpopulations seems to be related to the season studied and the ejaculate quality which would be a very important indicator of sperm function. The substantial information derived from these morphometric subpopulations has provided new knowledge which can be used in future studies using sperm morphometry as a seasonal indicator in ram ejaculates. PMID:22626774

Martí, J I; Aparicio, I M; Leal, C L V; García-Herreros, M

2012-08-01

363

Expression of two-pore domain potassium channels in nonhuman primate sperm*  

PubMed Central

Objective Two-pore domain potassium channels (K2P) play integral roles in cell signaling pathways by modifying cell membrane resting potential. Here we describe the expression and function of K2P channels in nonhuman primate sperm. Design Experimental animal study, randomized blinded concentration-response experiments. Setting University affiliated primate research center. Animal(s) Male nonhuman primates. Interventions Western blot and immunofluorescent analysis of epididymal sperm samples. Kinematic measures (VCL and ALH) and acrosome status were studied in epidydimal sperm samples exposed to K2P agonist (Docosahexaenoic acid) and antagonist (Gadolinium). Main outcome measures Semi-quantitative protein expression and cellular localization and quantitative changes in specific kinematic parameters and acrosome integrity. Results Molecular analysis demonstrated expression and specific regional distribution of TRAAK, TREK-1, and TASK-2 in nonhuman primate sperm. Docosahexaenoic acid produced a concentration-dependent increase in curvilinear velocity (p < 0.0001) with concomitant concentration-dependent reductions in lateral head displacement (p = 0.005). Gadolinium reduced velocity measures (p < 0.01) without significantly affecting lateral head displacement. Conclusion(s) The results demonstrated for the first time, expression and function of K2P potassium channels in nonhuman primate sperm. The unique, discrete distributions of K2P channels in nonhuman primate sperm suggest specific roles for this sub-family of ion channels in primate sperm function. PMID:17067589

Chow, Gregory E.; Muller, Charles H.; Curnow, Eliza C.; Hayes, Eric S.

2007-01-01

364

SLO3 K+ channels control calcium entry through CATSPER channels in sperm.  

PubMed

Here we show how a sperm-specific potassium channel (SLO3) controls Ca(2+) entry into sperm through a sperm-specific Ca(2+) channel, CATSPER, in a totally unanticipated manner. The genetic deletion of either of those channels confers male infertility in mice. During sperm capacitation SLO3 hyperpolarizes the sperm, whereas CATSPER allows Ca(2+) entry. These two channels may be functionally connected, but it had not been demonstrated that SLO3-dependent hyperpolarization is required for Ca(2+) entry through CATSPER channels, nor has a functional mechanism linking the two channels been shown. In this study we show that Ca(2+) entry through CATSPER channels is deficient in Slo3 mutant sperm lacking hyperpolarization; we also present evidence supporting the hypothesis that SLO3 channels activate CATSPER channels indirectly by promoting a rise in intracellular pH through a voltage-dependent mechanism. This mechanism may work through a Na(+)/H(+) exchanger (sNHE) and/or a bicarbonate transporter, which utilizes the inward driving force of the Na(+) gradient, rendering it intrinsically voltage-dependent. In addition, the sperm-specific Na(+)/H(+) exchanger (sNHE) possess a putative voltage sensor that might be activated by membrane hyperpolarization, thus increasing the voltage sensitivity of internal alkalization. PMID:25271166

Chávez, Julio César; Ferreira, Juan José; Butler, Alice; De La Vega Beltrán, José Luis; Treviño, Claudia L; Darszon, Alberto; Salkoff, Lawrence; Santi, Celia M

2014-11-14

365

Increasing Pleurotus ostreatus laccase production by culture medium optimization and copper/lignin synergistic induction.  

PubMed

Laccases have great biotechnological potential in diverse industries as they catalyze the oxidation of a broad variety of chemical compounds. Production of laccases by basidiomycetes has been broadly studied as they secrete the enzymes, grow on cheap substrates, and they generally produce more than one isoenzyme (constitutive and/or inducible). Laccase production and isoenzyme profile can be modified through medium composition and the use of inducers. The objective of this work was to increase laccase production by Pleurotus ostreatus CP-50 through culture medium optimization and the simultaneous use of copper and lignin as inducers. Increased fungal growth was obtained through the use of a factorial fractional experimental design 2??² where the influence of the nature and concentration of carbon and nitrogen sources was assessed. Although specific laccase production (U/mg biomass) decreased when malt extract medium was supplemented with carbon and nitrogen sources, fungal growth and laccase volumetric activity increased four and sixfold, respectively. The effect of media supplementation with copper and/or lignin on laccase production by P. ostreatus CP-50 was studied. A positive synergistic effect between copper and lignin was observed on laccase production. Overall, the use of an optimized medium and the simultaneous addition of copper and lignin improved growth, laccase volumetric activity, and process productivity by 4-, 60-, and 10-fold, respectively. PMID:20694851

Tinoco, Raunel; Acevedo, Abisaí; Galindo, Enrique; Serrano-Carreón, Leobardo

2011-04-01

366

Senescent sperm performance in old male birds.  

PubMed

Senescence is the deterioration of the phenotype with age caused by negative effects of mutations acting late in life or the physiological deterioration of vital processes. Birds have traditionally been assumed to senescence slowly despite their high metabolic rates, high blood sugar levels and high body temperature. Here we investigate the patterns of age-related performance of sperm of a long distance migrant, the barn swallow Hirundo rustica, varying in age from 1 to 6 years, analysed by the computer-assisted sperm analysis equipment. Sperm showed deteriorating performance in terms of linear movement, track velocity, straight line velocity and reduced proportions of rapidly moving, progressive and motile sperm with age. In a second series of experiments, we assessed performance of sperm from the same males in neutral medium and in medium derived from the reproductive tract of females in an attempt to test if sperm of old males performed relatively better in female medium, as expected from extra-pair paternity being negatively related to male age, but not to female age. Older males showed consistently better performance in female medium than in neutral medium in terms of track velocity, straight line velocity and reduced proportions of rapidly moving, progressive and motile sperm, whereas young males showed better performance in neutral medium. These results provide evidence of declining sperm performance for important reproductive variables not only with age, but also with the sperm of old males performing differentially better in female medium than young males. PMID:19032491

Møller, A P; Mousseau, T A; Rudolfsen, G; Balbontín, J; Marzal, A; Hermosell, I; De Lope, F

2009-02-01

367

The effects of radiation on sperm swimming behavior depend on plasma oxidative status in the barn swallow (Hirundo rustica).  

PubMed

Sperm are highly susceptible to reactive oxygen species (ROS) that can damage sperm DNA and structure, resulting in reduced fertilizing capacity. Exposure to radioactive contamination can also impair sperm swimming behavior and fertilizing ability, both through a reduction of sperm DNA integrity and via an increased generation of reactive oxygen species (ROS). However, the relationship between individual oxidative status and sperm swimming behavior has never been investigated in any wild population of animals exposed to radioactive contamination. We studied the motility of sperm collected from barn swallows, Hirundo rustica, breeding under different levels of radioactive contamination following the Chernobyl accident in 1986, in relation to individual oxidative status. We tested the hypothesis that the degree of impairment of sperm swimming behavior by radioactive contamination depended on plasma antioxidant capacity, the level of reactive oxygen metabolites (ROMs) and oxidative stress (sensu Costantini et al. 2006), a better oxidative status being associated with higher sperm motility. Sperm behavior parameters were subjected to principal component (PC) analysis, which extracted four PCs explaining 86% of the variance in sperm motility. PC2, representing sperm with high track velocity and ample lateral head displacement, was significantly predicted by the interaction between radiation level and either oxidative damage or oxidative stress. Contrary to our predictions, the highest values of PC2 were associated with relatively high radiation levels, particularly for high levels of either ROMs or oxidative stress. In addition, there was a tendency for values of PC3 (representing the percent of motile sperm) and PC4 (representing slow sperm with high beat cross frequency) to depend on the interaction between radiation level and total plasma antioxidant protection. Our results confirm the importance of oxidative status in determining the genetic and physiological outcome of exposure to radioactive contamination, complementing previous studies relating sperm abnormality to circulating levels of specific antioxidants. Our results also complement previous evidence that oxidative damage of sperm was negatively related to sperm motility, thus indicating a possible trade-off in quenching pro-oxidant compounds in the plasma and the seminal fluid. PMID:21295152

Bonisoli-Alquati, Andrea; Møller, Anders Pape; Rudolfsen, Geir; Saino, Nicola; Caprioli, Manuela; Ostermiller, Shanna; Mousseau, Timothy A

2011-06-01

368

Sperm DNA Methylation Analysis in Swine Reveals Conserved and Species-Specific Methylation Patterns and Highlights an Altered Methylation at the GNAS Locus in Infertile Boars.  

PubMed

Male infertility is an increasing health issue in today's society for both human and livestock populations. In livestock, male infertility slows the improvement of animal selection programs and agricultural productivity. There is increasing evidence that epigenetic marks play an important role in the production of good-quality sperm. We therefore screened for specific or common epigenetic signatures of livestock infertility. To do so, we compared DNA methylation level in sperm DNA from fertile and infertile boars. We evaluated first the global level of sperm DNA methylation and found no difference between the two groups of boars. We then selected 42 loci of interest, most of them known to be imprinted in human or mice, and assessed the imprinting status of five of them not previously described in swine tissues: WT1, CNTN3, IMPACT, QPCT, and GRB10. DNA methylation level was then quantified in fertile and infertile boars at these 42 loci. Results from fertile boars indicated that the methylation level of the selected loci is highly conserved between pig, human, and mice, with a few exceptions, including the POU5F1 (OCT4) promoter and RTL1. Comparison between fertile and infertile boars revealed that one imprinted region, the GNAS locus, shows an increase in sperm DNA methylation in three out of eight infertile boars with low semen quality. This increase in DNA methylation is associated with an altered expression of the genes belonging to the GNAS locus, suggesting a new role for GNAS in the proper formation of functional gametes. PMID:25320151

Congras, Annabelle; Yerle-Bouissou, Martine; Pinton, Alain; Vignoles, Florence; Liaubet, Laurence; Ferchaud, Stéphane; Acloque, Hervé

2014-12-01

369

Study of Sperm Reproductive Parameters in Mature Zanjani Viper  

PubMed Central

Objective Zanjani viper (Vipera albicornuta) is an endemic venomous snake in East Azerbai- jan Province, Iran which is medically important due to its application for antivenin production in the laboratory. We need to produce this snake in captivity. This study was conducted to charac- terize mature male Zanjani viper and to evaluate its sperm reproductive parameters. Materials and Methods This applied- descriptive study was conducted on twenty Zan- jani viper samples collected from Ag Dag Mountain in East Azarbaijan Province, Iran, between September and October 2010. After the snakes were anesthetized and sacrificed humanly, their morphometric specifications and sperm reproductive parameters, including concentration, motility, vitality, morphology, and survival time, were measured. Results Morphometric specifications and evaluation of sperms of the snake showed the following information: Zanjani male viper, body length of 73.65 ± 4.35 cm, tail length of 5.465 ± 0.48 cm, and mature snakes with testicular volumes of 0.61 ± 0.81 ml (right) and of 0.46 ± 0.17 ml (left). Our findings revealed average sperm concen- tration of 0.47 ± 0.1 ×106ml-1, motility of 49 -55 %, vitality of 46.11 ± 9.63 %, normal morphology of 61.71 ± 5.3%, and survival time of 6 ± 2 hours at the laboratory tem- perature. Statistical analyses were performed using Student’s t test for comparison of two values, and one-way ANOVA was applied where three values were compared. Conclusion Results suggest that mature Zanjani male viper with mature sperms in its vas deferens is present in late summer and early autumn seasons in Bostanabad County, Iran. PMID:24567940

Moshiri, Malihe; Todehdehghan, Fatemeh; Shiravi, Abdolhossein

2014-01-01

370

Olfactory receptors are displayed on dog mature sperm cells  

PubMed Central

Olfactory receptors constitute a huge family of structurally related G protein-coupled receptors, with up to a thousand members expected. We have shown previously that genes belonging to this family were expressed in the male germ line from both dog and human. The functional significance of this unexpected site of expression was further investigated in the present study. We demonstrate that a few dog genes representative of various subfamilies of olfactory receptors are expressed essentially in testis, with little or no expression in olfactory mucosa. Other randomly selected members of the family show the expected site of expression, restricted to the olfactory system. Antibodies were generated against the deduced amino acid sequence of the most abundantly expressed olfactory receptor gene in dog testis. The purified serum was able to detect the gene product (DTMT receptor) in late round and elongated spermatids, as well as in the cytoplasmic droplet that characterizes the maturation of dog sperm cells, and on the tail midpiece of mature spermatozoa. Western blotting further confirmed the presence of a 40-kD immunoreactive protein in the membrane of mature sperm cells. Altogether , these results demonstrate that the main expression site of a subset of the large olfactory receptor gene family is not olfactory mucosa but testis. This expression correlates with the presence of the corresponding protein during sperm cell maturation, and on mature sperm cells. The pattern of expression is consistent with a role as sensor for unidentified chemicals possibly involved in the control of mammalian sperm maturation, migration, and/or fertilization. PMID:8253843

1993-01-01

371

Perinatal exposure to low doses of tributyltin chloride reduces sperm count and quality in mice.  

PubMed

Exposure to endocrine disruptors (EDs) during early development might lead to adverse health outcomes later in life. Tributyltin (TBT), a proven ED, is widely used in consumer goods and industrial products. Herein we demonstrate the effects of low doses of tributyltin chloride (TBTCl) on reproduction of male KM mice. Pregnant mice were administered by gavage with 0, 1, 10, or 100 ?g TBTCl/kg body weight/day from day 6 of pregnancy through the period of lactation. TBTCl dramatically decreased sperm counts and motility on postnatal days (PNDs) 49 and 152. Meanwhile, a significant increase in sperm abnormality was observed in exposed mice on PND 49, but comparable to that in the control on PND 152. The histopathological analysis of testes of treated animals showed a dose-dependent increase in sloughing of germ cells in seminiferous tubules. Mice treated with 10 ?g TBTCl/kg exhibited decreased intratesticular 17?-estradiol (E2) levels on PND 49, and then followed by an obvious recovery on PND 152. While, no significant differences in serum E2, testosterone (T) levels and intratesticular T levels were detectable between control and TBTCl-exposed offspring at the sacrifice. These results suggest that perinatal TBTCl exposure is implicated in causing long lasting alterations in male reproductive system and these changes may persist far into adulthood. © 2013 Wiley Periodicals, Inc. Environ Toxicol 30: 44-52, 2015. PMID:23913619

Si, Jiliang; Li, Peng; Xin, Quanbing; Li, Xuewen; An, Lihong; Li, Jie

2015-01-01

372

Chromosome aberrations in spermatogonia and sperm abnormalities in Curacron-treated mice.  

PubMed

Curacron is an organophosphorus pesticide widely used in cotton fields. In order to assay its mutagenic potential in mammalian germ cells chromosomal aberrations in spermatogonial cells and sperm abnormalities were examined in mice after Curacron treatment. For studying chromosomal aberrations mice were treated both acutely (single treatment) and subacutely (for 5 consecutive days) with 3 dose levels of Curacron, 12, 36 and 72 mg/kg. Curacron was found to produce a significant increase in structural chromosomal aberrations after acute and subacute treatments. This increase was dose-dependent. A dose-dependent inhibition in mitotic activity in spermatogonia was also found. For studying sperm abnormalities mice were treated for 5 consecutive days with 20, 40 and 60 mg/kg. Morphological sperm abnormalities increased significantly after treatment with Curacron. The increase was dose-dependent. An inhibition of 40.2% in sperm count and of 74.5% in sperm motility occurred after treatment with 60 mg/kg Curacron. These results show that Curacron has a damaging effect on spermatogonial cells as well as on sperm morphology. PMID:2704385

el Nahas, S M; de Hondt, H A; Abdou, H E

1989-04-01

373

Partial Deletion of Chromosome 8 ?-defensin Cluster Confers Sperm Dysfunction and Infertility in Male Mice  

PubMed Central

?-defensin peptides are a family of antimicrobial peptides present at mucosal surfaces, with the main site of expression under normal conditions in the male reproductive tract. Although they kill microbes in vitro and interact with immune cells, the precise role of these genes in vivo remains uncertain. We show here that homozygous deletion of a cluster of nine ?-defensin genes (Defb?9) in the mouse results in male sterility. The sperm derived from the mutants have reduced motility and increased fragility. Epididymal sperm isolated from the cauda should require capacitation to induce the acrosome reaction but sperm from the mutants demonstrate precocious capacitation and increased spontaneous acrosome reaction compared to wild-types but have reduced ability to bind the zona pellucida of oocytes. Ultrastructural examination reveals a defect in microtubule structure of the axoneme with increased disintegration in mutant derived sperm present in the epididymis cauda region, but not in caput region or testes. Consistent with premature acrosome reaction, sperm from mutant animals have significantly increased intracellular calcium content. Thus we demonstrate in vivo that ?-defensins are essential for successful sperm maturation, and their disruption leads to alteration in intracellular calcium, inappropriate spontaneous acrosome reaction and profound male infertility. PMID:24204287

Zhou, Yu S.; Webb, Sheila; Lettice, Laura; Tardif, Steve; Kilanowski, Fiona; Tyrrell, Christine; MacPherson, Heather; Semple, Fiona; Tennant, Peter; Baker, Tina; Hart, Alan; Devenney, Paul; Perry, Paul; Davey, Tracey; Barran, Perdita; Barratt, Chris L.; Dorin, Julia R.

2013-01-01

374

Sperm chromatin structure and male fertility: biological and clinical aspects.  

PubMed

Sperm chromatin/DNA integrity is essential for the accurate transmission of paternal genetic information, and normal sperm chromatin structure is important for sperm fertilizing ability. The routine examination of semen, which includes sperm concentration, motility and morphology, does not identify defects in sperm chromatin structure. The origin of sperm DNA damage and a variety of methods for its assessment are described. Evaluation of sperm DNA damage appears to be a useful tool for assessing male fertility potential both in vivo and in vitro. The possible impact of sperm DNA defects on the offspring is also discussed. PMID:16372115

Erenpreiss, J; Spano, M; Erenpreisa, J; Bungum, M; Giwercman, A

2006-01-01

375

Increased Matrix Metalloproteinase-13 Production With Aging by Human Articular Chondrocytes in Response to Catabolic Stimuli  

PubMed Central

Chondrocyte anabolic activity has been shown to decline with aging, but catabolic activity has received little attention. In this study, the effect of aging on the chondrocyte catabolic response was determined by stimulating isolated human chondrocytes with fibronectin fragments (FN-f) or interleukin-1? and measuring matrix metalloproteinase-13 (MMP-13) production as a catabolic response. A significant age-related increase in chondrocyte MMP-13 production was noted. FN-f stimulation of MMP-13 expression was blocked using a nuclear factor kappa-B (NF?B) inhibitor suggesting a role for NF?B in this chondrocyte catabolic response. Chondrocyte production of the NF?B-regulated cytokine interleukin-1? was also found to increase with donor age in unstimulated cells. These results demonstrate a significant age-related increase in chondrocyte catabolic responsiveness which could contribute to the development of osteoarthritis in older adults. PMID:16183949

Forsyth, Christopher B.; Cole, Ada; Murphy, Gillian; Bienias, Julia L.; Im, Hee-Jeong; Loeser, Richard F.

2006-01-01

376

The role of artificial intelligence and expert systems in increasing STS operations productivity  

NASA Technical Reports Server (NTRS)

Artificial Intelligence (AI) is discussed. A number of the computer technologies pioneered in the AI world can make significant contributions to increasing STS operations productivity. Application of expert systems, natural language, speech recognition, and other key technologies can reduce manpower while raising productivity. Many aspects of STS support lend themselves to this type of automation. The artificial intelligence section of the mission planning and analysis division has developed a number of functioning prototype systems which demonstrate the potential gains of applying AI technology.

Culbert, C.

1985-01-01

377

Deficiency of the transcription factor c- fos increases lipopolysaccharide-induced macrophage interleukin 12 production  

Microsoft Academic Search

Background: Interleukin 12 (IL-12) p70 is a heterodimeric protein (p35, p40 subunits) that promotes T-helper TH1-type cytokine response. In critically ill patients, after severe trauma or sepsis, IL-12 production is markedly impaired. We tested the hypothesis that deficiency of the transcription factor c-fos will increase macrophage IL-12 production. Methods: We harvested adherent peritoneal macrophages harvested from wild-type (WT), heterozygous c-fos

Sabita Roy; Richard Charboneau; Kelly Cain; Dean Melnyk; Roderick A. Barke

1999-01-01

378

Physiological and ecological effects of increasing temperature on fish production in lakes of Arctic Alaska.  

PubMed

Lake ecosystems in the Arctic are changing rapidly due to climate warming. Lakes are sensitive integrators of climate-induced changes and prominent features across the Arctic landscape, especially in lowland permafrost regions such as the Arctic Coastal Plain of Alaska. Despite many studies on the implications of climate warming, how fish populations will respond to lake changes is uncertain for Arctic ecosystems. Least Cisco (Coregonus sardinella) is a bellwether for Arctic lakes as an important consumer and prey resource. To explore the consequences of climate warming, we used a bioenergetics model to simulate changes in Least Cisco production under future climate scenarios for lakes on the Arctic Coastal Plain. First, we used current temperatures to fit Least Cisco consumption to observed annual growth. We then estimated growth, holding food availability, and then feeding rate constant, for future projections of temperature. Projected warmer water temperatures resulted in reduced Least Cisco production, especially for larger size classes, when food availability was held constant. While holding feeding rate constant, production of Least Cisco increased under all future scenarios with progressively more growth in warmer temperatures. Higher variability occurred with longer projections of time mirroring the expanding uncertainty in climate predictions further into the future. In addition to direct temperature effects on Least Cisco growth, we also considered changes in lake ice phenology and prey resources for Least Cisco. A shorter period of ice cover resulted in increased production, similar to warming temperatures. Altering prey quality had a larger effect on fish production in summer than winter and increased relative growth of younger rather than older age classes of Least Cisco. Overall, we predicted increased production of Least Cisco due to climate warming in lakes of Arctic Alaska. Understanding the implications of increased production of Least Cisco to the entire food web will be necessary to predict ecosystem responses in lakes of the Arctic. PMID:24963391

Carey, Michael P; Zimmerman, Christian E

2014-05-01

379

Physiological and ecological effects of increasing temperature on fish production in lakes of Arctic Alaska  

USGS Publications Warehouse

Lake ecosystems in the Arctic are changing rapidly due to climate warming. Lakes are sensitive integrators of climate-induced changes and prominent features across the Arctic landscape, especially in lowland permafrost regions such as the Arctic Coastal Plain of Alaska. Despite many studies on the implications of climate warming, how fish populations will respond to lake changes is uncertain for Arctic ecosystems. Least Cisco (Coregonus sardinella) is a bellwether for Arctic lakes as an important consumer and prey resource. To explore the consequences of climate warming, we used a bioenergetics model to simulate changes in Least Cisco production under future climate scenarios for lakes on the Arctic Coastal Plain. First, we used current temperatures to fit Least Cisco consumption to observed annual growth. We then estimated growth, holding food availability, and then feeding rate constant, for future projections of temperature. Projected warmer water temperatures resulted in reduced Least Cisco production, especially for larger size classes, when food availability was held constant. While holding feeding rate constant, production of Least Cisco increased under all future scenarios with progressively more growth in warmer temperatures. Higher variability occurred with longer projections of time mirroring the expanding uncertainty in climate predictions further into the future. In addition to direct temperature effects on Least Cisco growth, we also considered changes in lake ice phenology and prey resources for Least Cisco. A shorter period of ice cover resulted in increased production, similar to warming temperatures. Altering prey quality had a larger effect on fish production in summer than winter and increased relative growth of younger rather than older age classes of Least Cisco. Overall, we predicted increased production of Least Cisco due to climate warming in lakes of Arctic Alaska. Understanding the implications of increased production of Least Cisco to the entire food web will be necessary to predict ecosystem responses in lakes of the Arctic.

Carey, Michael P.; Zimmerman, Christian E.

2014-01-01

380

Physiological and ecological effects of increasing temperature on fish production in lakes of Arctic Alaska  

PubMed Central

Lake ecosystems in the Arctic are changing rapidly due to climate warming. Lakes are sensitive integrators of climate-induced changes and prominent features across the Arctic landscape, especially in lowland permafrost regions such as the Arctic Coastal Plain of Alaska. Despite many studies on the implications of climate warming, how fish populations will respond to lake changes is uncertain for Arctic ecosystems. Least Cisco (Coregonus sardinella) is a bellwether for Arctic lakes as an important consumer and prey resource. To explore the consequences of climate warming, we used a bioenergetics model to simulate changes in Least Cisco production under future climate scenarios for lakes on the Arctic Coastal Plain. First, we used current temperatures to fit Least Cisco consumption to observed annual growth. We then estimated growth, holding food availability, and then feeding rate constant, for future projections of temperature. Projected warmer water temperatures resulted in reduced Least Cisco production, especially for larger size classes, when food availability was held constant. While holding feeding rate constant, production of Least Cisco increased under all future scenarios with progressively more growth in warmer temperatures. Higher variability occurred with longer projections of time mirroring the expanding uncertainty in climate predictions further into the future. In addition to direct temperature effects on Least Cisco growth, we also considered changes in lake ice phenology and prey resources for Least Cisco. A shorter period of ice cover resulted in increased production, similar to warming temperatures. Altering prey quality had a larger effect on fish production in summer than winter and increased relative growth of younger rather than older age classes of Least Cisco. Overall, we predicted increased production of Least Cisco due to climate warming in lakes of Arctic Alaska. Understanding the implications of increased production of Least Cisco to the entire food web will be necessary to predict ecosystem responses in lakes of the Arctic. PMID:24963391

Carey, Michael P; Zimmerman, Christian E

2014-01-01