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1

Effect of increased scrotal temperature on sperm production in normal men  

Microsoft Academic Search

Objective: To determine whether application of polyester-lined athletic supports to bring the testes closer to the abdomen increases scrotal temperature and decreases sperm production.Design: Prospective clinical study.Setting: University academic medical center.Patient(s): Twenty-one healthy male volunteers.Intervention(s): The study consisted of a pretreatment period of 6 weeks, a treatment phase of 52 weeks, and a recovery phase until return to normal sperm

Christina Wang; Veronica McDonald; Andrew Leung; Laura Superlano; Nancy Berman; Laura Hull; Ronald S. Swerdloff

1997-01-01

2

Females become infertile as the stored sperm's oxygen radicals increase  

PubMed Central

Predicting infertility is central to reproductive biology, medicine and evolutionary biology. In-vitro studies suggest that oxidative sperm damage causes infertility. Oxidative sperm damage can be reduced via two fundamental pathways: the removal of oxygen radicals by antioxidants, or the interference with cell metabolism to reduce the formation of oxygen radicals. Oxidative damage protection of spermatozoa should evolve frequently, especially during female sperm storage. However, in-vivo evidence linking oxidative protection and fertility is rare. We show that the intra-sperm production rate of oxygen radicals and the sperm metabolic rate were reduced in female bedbugs, Cimex lectularius, compared to males, and females laid fertile eggs. Females became infertile when sperm oxygen radicals and sperm metabolic rate increased to male levels. Our results link female fitness to sublethal sperm damage, imply adaptive benefits of interfering with sperm metabolism and offer the hypothesis that polyandry may serve to replace low-quality sperm.

Reinhardt, Klaus; Ribou, Anne-Cecile

2013-01-01

3

VASECTOMY REVERSAL ASSOCIATED WITH INCREASED REACTIVE OXYGEN SPECIES PRODUCTION BY SEMINAL FLUID LEUKOCYTES AND SPERM  

Microsoft Academic Search

PurposeReactive oxygen species, which are primarily produced by leukocytes, are generally detrimental to sperm. High reactive oxygen species levels are found in men with abnormal sperm function. Since men often have poor sperm characteristics and infertility after vasectomy reversal, fertile men to determine if reactive oxygen species were elevated in the former group.

ROBERT H. SHAPIRO; CHARLES H. MULLER; GREGORY CHEN; RICHARD E. BERGER

1998-01-01

4

Sperm production responds to perceived sperm competition risk in male Drosophila melanogaster.  

PubMed

Postcopulatory sexual selection arising from female multiple mating leads to the evolution of ejaculates that maximize a male's reproductive success under sperm competition. Where the risk of sperm competition is variable, optimal fitness may be achieved by plastically altering ejaculate characteristics in response to the prevailing sperm competition environment. In the model species Drosophila melanogaster, males expecting to encounter sperm competition mate for longer and transfer more accessory proteins and sperm. Here we show that after being housed with a single rival for one week, the seminal vesicles of male D. melanogaster contain a significantly greater proportion of live sperm than those of males maintained alone, indicating adaptive adjustment of sperm quality in response to the perceived risk of sperm competition. This effect is due to an increase in the number of live sperm produced, indicating that males upregulate sperm production in response to the presence of rivals. Our data suggest that males show plasticity in the rate of spermatogenesis that is adaptive in the context of a fluctuating sperm competition environment. PMID:24769021

Moatt, Joshua P; Dytham, Calvin; Thom, Michael D F

2014-05-28

5

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.

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

2014-01-01

6

Saccharin consumption increases sperm DNA fragmentation and apoptosis in mice.  

PubMed

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

2014-05-01

7

Tritrichomonas fetus extracellular products decrease progressive motility of bull sperm.  

PubMed

Tritrichomonas fetus causes infertility and abortion in cattle; however, there is scarce information regarding the susceptibility of bovine sperm to this parasite. The objective of this study was to analyze in vitro the interaction between T. fetus and bovine sperm and to evaluate the effect of extracellular products secreted by the parasite on these reproductive cells. Sperm from five fertile bulls (Bos taurus taurus, Holstein-Friesian), selected through a Percoll gradient, adhered to T. fetus after 30min of interaction, resulting in agglutination between the two kinds of cells. Based on reverse transcription-polymerase chain reaction (RT-PCR), T. fetus continuously expressed its gene for cysteine peptidase in the presence or absence of sperm. Computer-assisted semen analysis (CASA) revealed that, after 1h incubation of sperm in T. fetus culture extract, the extracellular products secreted by the parasite decreased sperm progressive motility (P<0.05). Although T. fetus extracellular products did not lead to loss of sperm viability (P<0.05) based on the Annexin-V/propidium iodide assay, the percentage of Annexin-V fluorescein isothiocyanate-positive and propidium iodide-positive cells increased (P<0.05) during incubation of sperm in T. fetus culture extract, consistent with cellular damage. In conclusion, extracellular products secreted by T. fetus were cytotoxic to bovine sperm, as they decreased sperm progressive motility; perhaps this contributes to the pathogenesis of T. fetus-induced infertility. PMID:19783033

Ribeiro, C M; Falleiros, M B; Bicudo, S D; Júnior, J P Araujo; Golim, M A; Filho, F C Silva; Padovani, C R; Modolo, J R

2010-01-01

8

Reproductive function of the male obese Zucker rats: alteration in sperm production and sperm DNA damage.  

PubMed

Obesity has been considered a public health issue in many countries and is of increasing concern for authorities over the past 6 years. The Zucker rat is a good experimental model for obesity and diabetes studies due to its metabolic characteristics that are similar to those developed by humans. A total of 12 obese Zucker rats and their lean littermates were killed in pubertal and young adult phases for assessing organ weights (testis and epididymis), testicular histomorphometric and stereological analyses, daily sperm production, and transit time in the epididymis. Sperm integrity was also investigated in the adult animals using the Comet assay. Alterations in organ weights, seminiferous epithelium architecture, sperm production, and transit time were noticed in the pubertal fatty rats. The volume density of the lymphatic space was decreased in both the ages. Adult animals had a significant increase in the extent of damage found in sperm DNA. Our results show for the first time that leptin receptor deficiency compromises sperm production during puberty and that genetic obese Zucker rats have increased sperm DNA fragmentation. PMID:23800399

Vendramini, V; Cedenho, A P; Miraglia, S M; Spaine, D M

2014-02-01

9

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.

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

2013-01-01

10

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

PubMed

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

2013-04-22

11

Luteinizing hormone plasmid therapy results in long-lasting high circulating Lh and increased sperm production in European sea bass (Dicentrarchus labrax).  

PubMed

The present work aimed at evaluating the potential of intramuscular injection of a hormone-coding gene as an approach for gene therapy in fish. A plasmid containing luteinizing hormone (Lh) in a single-chain (sc) form, pCMV-scLh, was chosen as the coding gene, and sea bass was chosen as the target species. In vivo injection of pCMV-scLh in muscle of juvenile sea bass rendered plasma Lh levels higher than 50 ng/ml in 40% of the injected fish, while these Lh levels were only detected in 4% of controls. Injections performed on spermiating broodstock demonstrated that this strategy produced an active Lh able to increase sperm production without affecting its quality, in terms of density. Compared with the injection of a recombinant single-chain Lh, plasmid injection provoked longer-lasting and higher plasma Lh levels. These results show that sea bass skeletal muscle is able to uptake plasmid DNA and to secrete the encoded protein to the bloodstream. Therefore, we propose somatic gene transfer as a realistic approach for hormone therapy of dysfunctions due to low hormone levels in fish or just to synchronize spawning. PMID:23255338

Mazón, María José; Zanuy, Silvia; Muñoz, Iciar; Carrillo, Manuel; Gómez, Ana

2013-02-01

12

Sound production in neonate sperm whales (L)  

NASA Astrophysics Data System (ADS)

Acoustic data from two sperm whale neonates (Physeter macrocephalus) in rehabilitation are presented and implications for sound production and function are discussed. The clicks of neonate sperm whale are very different from usual clicks of adult specimens in that neonate clicks are of low directionality [SL anomaly (0°-90°) <8 dB], long duration (2-12 ms), and low frequency (centroid frequency between 300 and 1700 Hz) with estimated SLs between 140 and 162 dB//1 ?Pa (rms). Such neonate clicks are unsuited for biosonar, but can potentially convey homing information between calves and submerged conspecifics in open ocean waters at ranges of some 2 km. Moreover, it is demonstrated that sperm whale clicks are produced at the anterior placed monkey lips, thereby substantiating a key point in the modified Norris and Harvey theory and supporting the unifying theory of sound production in odontocetes.

Madsen, P. T.; Carder, D. A.; Au, W. W. L.; Nachtigall, P. E.; Møhl, B.; Ridgway, S. H.

2003-06-01

13

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

14

Sperm Pretreatment with Dithiothreitol Increases Male Pronucleus Formation Rates After Intracytoplasmic Sperm Injection (ICSI) in Swamp Buffalo Oocytes  

PubMed Central

Abstract Failure of male pronucleus formation has hampered the success of intracytoplasmic sperm injection (ICSI) in swamp buffalo. The aim of the present study was to improve male pronucleus formation by pretreating sperm with various chemicals before ICSI. In Experiments1 and 2, sperm were treated according to one of the following protocols: (1) 0.1% Triton-X 100 (TX) for 1 min, (2) 10 µM calcium ionophore (CaI) for 20 min, (3) freezing and thawing (FT) without any cryoprotectant, or (4) no treatment (control). These sperm treatment groups then either did or did not receive additional sperm treatment with 5 mM dithiothreitol (DTT) for 20 min. Acrosomal integrity (Experiment 1) and DNA fragmentation (Experiment 2) were evaluated in the sperm before ICSI. In Experiment 3, oocytes matured in vitro were subjected to ICSI using pretreated sperm as described above and then were cultured either with or without activation. The TX- and CaI-treated sperm caused an increase in the number of acrosome-loss sperm, whereas the FT treatment and control increased the proportion of acrosome-reacted sperm (P<0.05). The DNA fragmentation did not differ among treatments (P>0.05). At 18 h post-ICSI, pronucleus (PN) formation was found only in activated oocytes. The majority of the activated ICSI oocytes contained intact sperm heads. Normal fertilization was observed in the CaI and FT treatment groups and control group when sperm were treated with DTT before ICSI. In conclusion, DTT treatment of sperm with reacted acrosomes before ICSI together with activation of the ICSI oocytes is important for successful male pronucleus formation.

CHANKITISAKUL, Vibuntita; AM-IN, Nutthee; THARASANIT, Theerawat; SOMFAI, Tamas; NAGAI, Takashi; TECHAKUMPHU, Mongkol

2012-01-01

15

Diethylstilbestrol-treated adult rats with altered epididymal sperm numbers and sperm motility parameters, but without alterations in sperm production and sperm morphology.  

PubMed

In this study, we characterized estrogenic effects of diethylstilbestrol (DES) on reproductive parameters in male rats to identify a minimal dose level that alters epididymal and sperm functions but has little or no effect on sperm production and/or spermatogenesis. Adult rats (five animals/group) received s.c. injections of 0.2 ml of corn oil containing DES at a rate of 1.0 mg, 200 microg, 40 microg, 8 microg, 1.6 microg, or 320 ng x rat(-1) x day(-1) for 12 days. The control group received corn oil only. DES effects were similar in the 8-microg group and higher dose groups and included significant (P < or = 0.05) reductions in 1) absolute and relative weights of the head and body of the epididymis (EP), tail of the EP, and seminal vesicle, 2) numbers of sperm in both regions of the EP, and 3) motility characteristics in sperm collected from the tail of the EP. Conversely, no significant changes were observed in relative testis weight, daily sperm production, spermatogenesis, seminiferous epithelial height in stage VII, and sperm morphology. All of the above parameters in the 1.6-microg group (except seminal vesicle weight) and 320-ng group were comparable to those of controls. Plasma testosterone (T) level was reduced to an almost undetectable level in the > or = 8-microg groups and to a very low level in the 1.6-microg group (0.35 vs. 2.36 ng/ml in controls or 320-ng group), but LH level was unaltered. In a parallel fertility study, males received DES at a rate of 40, 8, or 1.6 microg x rat(-1) x day(-1) for 12 days prior to and 12 days during cohabitation (1:1) with untreated females. Of the 15 females cohabited with treated males (5 females/dose), none in the 40-microg and 8-microg groups and 1 in the 1.6-microg group formed a copulatory plug and delivered 8 pups, in contrast to 5/5 copulatory plugs and 13-15 pups/litter in the controls. DES at a rate of 8 microg x rat(-1) x day(-1) for 12 days reduced EP weights, sperm numbers in the EP, and sperm motility patterns but caused minimal to no alterations in daily sperm production, spermatogenesis, or sperm morphology. Factors other than T, or in addition to lower T, may be responsible for DES-induced reproductive disorders (despite lower T, sperm contents and sperm motility patterns in the EP were normal in the 1.6-microg group). Deficits in EP sperm functions and/or sexual behavior (as evident from absence of copulatory plugs) probably accounted for reduced fertility in treated males. PMID:11207210

Goyal, H O; Braden, T D; Mansour, M; Williams, C S; Kamaleldin, A; Srivastava, K K

2001-03-01

16

Reduction of centrifugation force in discontinuous percoll gradients increases in vitro fertilization rates without reducing bovine sperm recovery.  

PubMed

The objective of this study was to determine the effect of different centrifugation forces in bovine sperm separation by discontinuous Percoll gradients for in vitro fertilization IVF. The semen samples from each bull were pooled or each bull were centrifuged separately and centrifuged in discontinuous Percoll gradients (30, 60 and 90%) at different forces: F1 (9000×g), F2 (6500×g), F3 (4500×g) and F4 (2200×g), according experiment. The sperm samples were evaluated to determine the concentration, motility, vigor, morphology, reactive oxygen species (ROS), integrity of the plasma membrane, lipid peroxidation, antioxidants and embryo development were also evaluated. No difference was observed in the concentration of sperm submitted to different centrifugation forces. The total percentage of motile sperm was increased after centrifugation at F3 and F4, and the ROS production at F1 was greater than the other forces. When the bulls semen were processed individually, no significant differences were observed for the sperm quality parameters between F1 and F4, including lipid peroxidation, antioxidants, cleavage rate and average time to the first cleavage. This work demonstrated for the first time that centrifugation at 2200×g enhanced the sperm penetration and fertilization rates without reducing sperm recovery compared to the typical centrifugation force (9000×g) currently used by the commercial bovine IVF industry. PMID:24646635

Guimarães, A C G; Leivas, F G; Santos, F W; Schwengber, E B; Giotto, A B; Machado, C I U; Gonçalves, C G M; Folchini, N P; Brum, D S

2014-05-01

17

Antlers honestly advertise sperm production and quality  

PubMed Central

Evolutionary theory proposes that exaggerated male traits have evolved via sexual selection, either through female mate choice or male–male competition. While female preferences for ornamented males have been amply demonstrated in other taxa, among mammals sexual characters are commonly regarded as weapons whose main function is to enhance male competitiveness in agonistic encounters. One particularly controversial hypothesis to explain the function of male sexual characters proposes that they advertise male fertility. We test this hypothesis in red deer (Cervus elaphus), a species where sexual characters (antlers) reach an extreme degree of elaboration. We find that a global measure of relative antler size and complexity is associated with relative testes size and sperm velocity. Our results exclude the possibility that condition dependence, age or time of culling, drive these associations. Red deer antlers could signal male fertility to females, the ability to avoid sperm depletion throughout the reproductive season and/or the competitive ability of ejaculates. By contrast, male antlers could also signal to other males not only their competitive ability at the behavioural level (fighting ability) but also at the physiological level (sperm competition).

Malo, Aurelio F.; Roldan, Eduardo R. S.; Garde, Julian; Soler, Ana J.; Gomendio, Montserrat

2005-01-01

18

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

19

Drosophila melanogaster males increase the number of sperm in their ejaculate when perceiving rival males.  

PubMed

It is common for females from many species to mate with multiple males within one reproductive cycle. As a result, sperm from different males come into contact in the female reproductive organs, where they compete for ova fertilization. This sperm competition appears to drive the ejaculation of a greater number of sperm than required to fertilize the ova. Both models and experimental observations indicate that males adjust the number of sperm in their ejaculate to the presence of rival males. Here, we show that Drosophila melanogaster males increase sperm allocation immediately after perceiving the presence of other males, but not females. Consistent with previous reports, we show that males use both auditory and olfactory modalities to determine the identity of potential rivals in their environment and we further show that these modalities are required for males to modulate sperm allocation. Our results support the sperm competition risk assessment theory, which predicts that males increase sperm allocation while perceiving the immediate risk of sperm competition, and reconcile previous observations in D. melanogaster that were at odds with this model. PMID:23178803

Garbaczewska, Martyna; Billeter, Jean-Christophe; Levine, Joel D

2013-03-01

20

Coincubation of Human Spermatozoa with Chlamydia trachomatis In Vitro Causes Increased Tyrosine Phosphorylation of Sperm Proteins  

Microsoft Academic Search

Elementary bodies (EBs) of the obligate intracellular bacterium Chlamydia trachomatis are responsible for the first step of attachment to host cells. We have studied the effects of EBs on human sperm protein tyrosine phosphorylation, which is important to sperm function. Indirect immunofluorescence using antiphosphoty- rosine antibodies showed that serovar E, but not LGV, caused increased tyrosine phosphorylation which was localized

S. Hosseinzadeh; I. A. Brewis; A. A. Pacey; H. D. M. Moore; A. Eley

2000-01-01

21

Phenotypic plasticity in sperm production rate: there’s more to it than testis size  

Microsoft Academic Search

Evolutionary theory predicts that males should produce more sperm when sperm competition is high. Because sperm production\\u000a rate is difficult to measure in most organisms, comparative and experimental studies have typically used testis size instead,\\u000a while assuming a good correspondence between testis size and sperm production rate. Here we evaluate this common assumption\\u000a using the marine flatworm Macrostomum lignano, in

Lukas Schärer; Dita B. Vizoso

2007-01-01

22

Cryopreservation increases coating of bull sperm by seminal plasma binder of sperm proteins BSP1, BSP3, and BSP5.  

PubMed

Artificial insemination with frozen semen allows affordable, worldwide dissemination of gametes with superior genetics. Nevertheless, sperm are damaged by the cryopreservation process. Elucidating the molecular effects of cryopreservation on sperm could suggest methods for improving fertility of frozen/thawed semen. This study was undertaken to examine the effect of cryopreservation on the coating of sperm by binder of sperm (BSP) proteins in seminal plasma. BSP proteins are secreted by the seminal vesicles and coat the surface of sperm by partially intercalating into the outer leaflet of the sperm plasma membrane. The BSP proteins are known to play roles in the formation of the oviductal sperm storage reservoir and in sperm capacitation. We investigated the effects of cryopreservation on the sperm BSP protein coat using Bovipure to separate live sperm from extended semen and then assaying the amounts of BSP proteins on sperm using quantitative western blotting with custom-made antibodies against unique sequences of each BSP protein. Greater amounts of all three BSP proteins (BSP1, BSP3, and BSP5) were detected on frozen/thawed sperm than on fresh sperm. Furthermore, the reduction of BSP3 from 15 to 13?kDa in mass, which occurs during incubation of sperm under mild capacitating conditions, was enhanced by cryopreservation. We concluded that freezing alters the BSP protein coating on sperm, which could account in part for reduced fertility of cryopreserved semen samples. PMID:23740081

Ardon, Florencia; Suarez, Susan S

2013-08-01

23

What Sperm Can Teach us About Energy Production  

PubMed Central

Mammalian sperm have evolved under strict selection pressures that have resulted in a highly polarized and efficient design. A critical component of that design is the compartmentalization of specific metabolic pathways to specific regions of the cell. Although the restricted localization of mitochondria to the midpiece is the best known example of this design, the organization of the enzymes of glycolysis along the fibrous sheath is the primary focus of this review. Evolution of variants of these metabolic enzymes has allowed them to function when tethered, enabling localized energy production that is essential for sperm motility. We close by exploring how this design might be mimicked to provide an energy-producing platform technology for applications in nanobiotechnology.

Mukai, C.; Travis, AJ.

2013-01-01

24

Effects of thio-tepa and hydroxyurea on sperm production in Lakeview hamsters.  

PubMed

The spermatogenic cell sensitivity in the induction of sperm abnormalities by two antineoplastic agents, thio-TEPA and hydroxyurea in inbred Lakeview hamsters was studied and the results were compared with those of similar investigations with mice. Testis weights, epididymal sperm numbers, and body weights were also monitored up to 12 wk after treatment. Thio-TEPA administration increased sperm abnormalities and reduced testis weights as well as sperm numbers in a dose-dependent manner at wk 4 and 12 after treatment. Hydroxyurea administration was ineffective in inducing sperm abnormalities, but testis weights and sperm numbers were adversely affected dose-dependent changes in body weights after treatment with either agent were also recorded. The findings with thio-TEPA on sperm morphology agree with those reported for the mouse. However, unlike the results of the mouse studies, hydroxy-urea effects on sperm shape were not observed in the hamster. PMID:6799658

Singh, H; Taylor, C

1981-01-01

25

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

26

Increased Aneuploidy Rate in Sperm With Fragmented DNA as Determined by the Sperm Chromatin Dispersion (SCD) Test and FISH Analysis  

Microsoft Academic Search

Previous studies suggest that sperm DNA fragmen- tation may be associated with aneuploidy. However, currently available tests have not made it possible to simultaneously perform DNA fragmentation and chromosomal analyses on the same sperm cell. The recently introduced sperm chromatin dispersion (SCD) test allows users to determine this relationship. Semen samples from 16 males, including 4 fertile donors, 7 normozoospermic,

LOURDES MURIEL; VICENTE GOYANES; ENRIQUE SEGRELLES; JAIME GOSALVEZ; JUAN G. ALVAREZ; JOSELUIS FERNANDEZ

2007-01-01

27

Dietary supplementation with a source of omega-3 fatty acids increases sperm number and the duration of ejaculation in boars  

Microsoft Academic Search

Development of nutritional strategies to increase the production of fertile sperm would further enhance the distribution of superior genetic material by AI. The objective was to determine the effects of a dietary source of omega-3 fatty acids in boars on semen characteristics and sexual behavior. Boars were fed daily 2.2kg of a diet top-dressed with 0.3kg of corn (controls; n=12)

M. J. Estienne; A. F. Harper; R. J. Crawford

2008-01-01

28

Organophosphorous pesticide exposure increases the frequency of sperm sex null aneuploidy.  

PubMed Central

It has been estimated that 4 of 1,000 live births and 35% of spontaneous abortions are aneuploid and that an important proportion of embryo and newborn aneuploidy is of paternal origin. Exposure to organophosphorous pesticides (OP) has been associated with sperm hyperploidy/polyploidy. Therefore, we aimed to assess the frequency of sperm aneuploidy (X, Y, and 18) and its relationship with urinary OP metabolites in agricultural workers. We performed multicolor fluorescence in situ hybridization on samples from nine men obtained before and during the pesticide spraying season to assess sperm aneuploidy. We measured urinary OP metabolite levels by gas-liquid chromatography. Aneuploidies were found in 0.67% of total sperm nuclei. The most frequent aneuploidy was the lack of a sexual chromosome or sex null (0.19%), followed by XY18 (0.15%) and XY18-18 (0.06%). OP metabolites detected at higher concentrations were dimethylthiophosphate, dimethyldithiophosphate, and diethylphosphate (DEP). There were no differences in average aneuploidy frequency or urinary metabolite levels between samples collected before and after exposure. However, Poisson regression analysis adjusted for age, alcohol intake, and sperm concentration showed significant associations between OP metabolite concentrations and increased frequency of sperm aneuploidies. The association was more evident between DEP and sex null, and the risk increased further during the spraying season. Thus, OP exposure could interfere with sperm chromosome segregation and increase the risk for genetic syndromes, such as Turner's. Further studies are required to assess the prevalence of spontaneous abortions, birth defects, and genetic syndromes in agricultural communities.

Recio, R; Robbins, W A; Borja-Aburto, V; Moran-Martinez, J; Froines, J R; Hernandez, R M; Cebrian, M E

2001-01-01

29

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

30

Reduced metabolic rate and oxygen radicals production in stored insect sperm.  

PubMed

Females of internally fertilizing species can significantly extend sperm lifespan and functionality during sperm storage. The mechanisms for such delayed cellular senescence remain unknown. Here, we apply current hypotheses of cellular senescence developed for diploid cells to sperm cells, and empirically test opposing predictions on the relationship between sperm metabolic rate and oxygen radical production in an insect model, the cricket Gryllus bimaculatus. Using time-resolved microfluorimetry, we found a negative correlation between metabolic rate (proportion of protein-bound NAD[P]H) and in situ intracellular oxygen radicals production in freshly ejaculated sperm. In contrast, sperm stored by females for periods of 1 h to 26 days showed a positive correlation between metabolic rate and oxygen radicals production. At the same time, stored sperm showed a 37 per cent reduced metabolic rate, and 42 per cent reduced reactive oxygen species (ROS) production, compared with freshly ejaculated sperm. Rank differences between males in ROS production and metabolic rate observed in ejaculated sperm did not predict rank differences in stored sperm. Our method of simultaneously measuring ROS production and metabolic rate of the same sample has the advantage of providing data that are independent of sperm density and any extracellular antioxidants that are proteins. Our method also excludes effects owing to accumulated hydrogen peroxide. Our results unify aspects of competing theories of cellular ageing and suggest that reducing metabolic rate may be an important means of extending stored sperm lifespan and functionality in crickets. Our data also provide a possible explanation for why traits of ejaculates sampled from the male may be rather poor predictors of paternity in sexual selection studies and likelihood of pregnancy in reproductive medicine. PMID:22279170

Ribou, Anne-Cécile; Reinhardt, Klaus

2012-06-01

31

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

32

Flow cytometric sexing of spider sperm reveals an equal sperm production ratio in a female-biased species.  

PubMed

Producing equal amounts of male and female offspring has long been considered an evolutionarily stable strategy. Nevertheless, exceptions to this general rule (i.e. male and female biases) are documented in many taxa, making sex allocation an important domain in current evolutionary biology research. Pinpointing the underlying mechanism of sex ratio bias is challenging owing to the multitude of potential sex ratio-biasing factors. In the dwarf spider, Oedothorax gibbosus, infection with the bacterial endosymbiont Wolbachia results in a female bias. However, pedigree analysis reveals that other factors influence sex ratio variation. In this paper, we investigate whether this additional variation can be explained by the unequal production of male- and female-determining sperm cells during sperm production. Using flow cytometry, we show that males produce equal amounts of male- and female-determining sperm cells; thus bias in sperm production does not contribute to the sex ratio bias observed in this species. This demonstrates that other factors such as parental genes suppressing endosymbiont effects and cryptic female choice might play a role in sex allocation in this species. PMID:24850893

Vanthournout, B; Deswarte, K; Hammad, H; Bilde, T; Lambrecht, B; Hendrickx, F

2014-05-01

33

Linear increase of diploidy in human sperm with age: A four-colour FISH study  

Microsoft Academic Search

The aim of this study was to determine if donor age is associated with an increased incidence of diploidy and of disomy for the sex chromosomes and for chromosomes 6 and 21. We used simultaneous fluorescence in situ hybridisation (FISH) for chromosomes 6, 21, X and Y in sperm from 18 healthy donors, aged 24–74 years (mean 48.8 years). A

Mercè Bosch; Osvaldo Rajmil; Olga Martínez-Pasarell; Josep Egozcue; Cristina Templado

2001-01-01

34

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

35

Sperm-mediated gene transfer: effect on bovine in vitro embryo production.  

PubMed

The technique of sperm-mediated gene transfer (SMGT) can be used to delivery exogenous DNA into the oocyte. However, it has low repeatability and produces inconsistent results. In order to optimize this technique, it is necessary to study the mechanism by which DNA enters the sperm cell and integrates in the sperm genome. Furthermore, studies must focus in the maintenance of sperm cell viability and function. The aim of this study was to evaluate different SMGT protocols of sperm electroporation or capacitation (CaI) aiming to maintain sperm viability in the production of bovine embryos in vitro. Frozen-thawed semen was divided in two experimental groups (electroporation or CaI) and one control group (non-treated cells). For the electroporation method, five different voltages (100, 500, 750, 1000 or 1500 V) with 25 ?F capacitance were used. For CaI treatment, combinations of two CaI concentrations (250 nM or 500 nM), two incubation periods of sperm cells with CaI (1 or 5 min) and two incubation periods that mimicked time of sperm cell interaction with exogenous DNA molecules (1 or 2 h) were evaluated. According to our data, electroporation and CaI treatments do not prevent sperm penetration and oocyte fertilization and can be an alternative method to achieve satisfactory DNA delivery in SMGT protocols. PMID:22805109

Simões, Renata; Nicacio, Alessandra Corallo; Binelli, Mario; de Paula-Lopes, Fabiola Freitas; Milazzotto, Marcella Pecora; Visintin, José Antonio; D'Ávila Assumpção, Mayra Elena Ortiz

2013-11-01

36

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

37

Testes mass, but not sperm length, increases with higher levels of polyandry in an ancient sex model.  

PubMed

There is strong evidence that polyandrous taxa have evolved relatively larger testes than monogamous relatives. Sperm size may either increase or decrease across species with the risk or intensity of sperm competition. Scorpions represent an ancient direct mode with spermatophore-mediated sperm transfer and are particularly well suited for studies in sperm competition. This work aims to analyze for the first time the variables affecting testes mass, ejaculate volume and sperm length, according with their levels of polyandry, in species belonging to the Neotropical family Bothriuridae. Variables influencing testes mass and sperm length were obtained by model selection analysis using corrected Akaike Information Criterion. Testes mass varied greatly among the seven species analyzed, ranging from 1.6±1.1 mg in Timogenes dorbignyi to 16.3±4.5 mg in Brachistosternus pentheri with an average of 8.4±5.0 mg in all the species. The relationship between testes mass and body mass was not significant. Body allocation in testes mass, taken as Gonadosomatic Index, was high in Bothriurus cordubensis and Brachistosternus ferrugineus and low in Timogenes species. The best-fitting model for testes mass considered only polyandry as predictor with a positive influence. Model selection showed that body mass influenced sperm length negatively but after correcting for body mass, none of the variables analyzed explained sperm length. Both body mass and testes mass influenced spermatophore volume positively. There was a strong phylogenetic effect on the model containing testes mass. As predicted by the sperm competition theory and according to what happens in other arthropods, testes mass increased in species with higher levels of sperm competition, and influenced positively spermatophore volume, but data was not conclusive for sperm length. PMID:24736525

Vrech, David E; Olivero, Paola A; Mattoni, Camilo I; Peretti, Alfredo V

2014-01-01

38

Testes Mass, but Not Sperm Length, Increases with Higher Levels of Polyandry in an Ancient Sex Model  

PubMed Central

There is strong evidence that polyandrous taxa have evolved relatively larger testes than monogamous relatives. Sperm size may either increase or decrease across species with the risk or intensity of sperm competition. Scorpions represent an ancient direct mode with spermatophore-mediated sperm transfer and are particularly well suited for studies in sperm competition. This work aims to analyze for the first time the variables affecting testes mass, ejaculate volume and sperm length, according with their levels of polyandry, in species belonging to the Neotropical family Bothriuridae. Variables influencing testes mass and sperm length were obtained by model selection analysis using corrected Akaike Information Criterion. Testes mass varied greatly among the seven species analyzed, ranging from 1.6±1.1 mg in Timogenes dorbignyi to 16.3±4.5 mg in Brachistosternus pentheri with an average of 8.4±5.0 mg in all the species. The relationship between testes mass and body mass was not significant. Body allocation in testes mass, taken as Gonadosomatic Index, was high in Bothriurus cordubensis and Brachistosternus ferrugineus and low in Timogenes species. The best-fitting model for testes mass considered only polyandry as predictor with a positive influence. Model selection showed that body mass influenced sperm length negatively but after correcting for body mass, none of the variables analyzed explained sperm length. Both body mass and testes mass influenced spermatophore volume positively. There was a strong phylogenetic effect on the model containing testes mass. As predicted by the sperm competition theory and according to what happens in other arthropods, testes mass increased in species with higher levels of sperm competition, and influenced positively spermatophore volume, but data was not conclusive for sperm length.

Vrech, David E.; Olivero, Paola A.; Mattoni, Camilo I.; Peretti, Alfredo V.

2014-01-01

39

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.

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

40

Production of female bovine embryos with sex-sorted sperm using intracytoplasmic sperm injection: efficiency and in vitro developmental competence.  

PubMed

The production of embryos with a preselected sex sperm is important in the livestock industry. In this study, we examined the efficiency of producing female embryos by intracytoplasmic sperm injection (ICSI) with flow cytometry sorted (ssICSI) and unsorted (usICSI) bovine sperm, and their developmental competence in vitro. For comparison, bovine embryos were also produced by in vitro fertilization (IVF) with sorted (ssIVF) and unsorted (usIVF) bovine sperm. The semen used in this study was from a bull selected for its high fertility and blastocyst developmental competence among four bulls. We first examined and compared pronuclear (PN) formation and cleavage rates of the produced embryos among the treatment groups. Our results demonstrated that PN formation rates (judged by two pronucleus [2PN]) and cleavage rates in ssIVF group (23.1% and 43.6%) were lower than those in the usIVF (71.1% and 71.6%), usICSI (73.1% and 92.8%) and ssICSI (75% and 79.1%) groups, respectively (P < 0.05). Moreover, the blastocyst formation rate in the ssIVF group was less than those in the usIVF, usICSI, and ssICSI groups (2.7% vs. 30.2%, 28.7% and 24.7%, respectively; P < 0.05). Importantly, we reported that the blastocyst formation rate in the ssICSI group was similar to that in the usICSI group, which indicated that ICSI can rescue the damage introduced to sperm by flow cytometry-mediated sex-sorting. Of note, we achieved a blastocyst formation rate in the ssICSI group to be comparable with the usIVF group. We then examined embryo quality by counting the number of normal and apoptotic cells in blastocysts. It was found that, despite the fact that blastocyst formation rate in the ssIVF group was significantly lower than those in the usIVF, usICSI and ssICSI groups, there was no difference in total and apoptotic cell numbers among these groups (P > 0.05). Finally, karyotyping analysis demonstrated that the proportion of female embryos in the ssICSI and ssIVF groups was 100%, whereas it was 58.8% and 57.8% in the usIVF and usICSI groups, respectively. In conclusion, ICSI with flow cytometry sorted bovine sperm provides an alternative approach to produce embryos with predetermined sex. PMID:24360289

Jo, Hyun-Tae; Bang, Jae-Il; Kim, Seong-Su; Choi, Byung-Hyun; Jin, Jong-In; Kim, Heyng-Lyool; Jung, In-Suk; Suh, Tae-Kwang; Ghanem, Nasser; Wang, Zhongde; Kong, Il-Keun

2014-03-15

41

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

42

Sexing sperm of domestic animals.  

PubMed

The ability to preselect or predetermine the sex of offspring prior to conception is a highly desired technological tool for assisted female breeding programs specifically for milk production, and in males, for meat production and increasing livestock numbers. The current technology is based on the well-known differences in X- and Y-sperm in the amount of DNA. The technology uses modified flow cytometric instrumentation for sorting X- and Y-bearing sperm. The method can be validated on the basis of live births, laboratory reanalysis of sorted sperm for DNA content, and embryo biopsy for sex determination. Currently, the sex of animals has been predetermined with 90 % accuracy by sexing spermatozoa. In the bovine breeding industry, flow cytometric sperm sexing has not fulfilled its original promise. Sexed sperm doses are too expensive for widespread application while the fertility of sexed sperm doses is lower than unsexed ones. Essentially all bovine sexed semen is frozen and then applied through artificial insemination (AI) or in vitro fertilization. There is still a need in the animal breeding industry to develop a technique for sperm sexing that provides sufficient spermatozoa for AI doses, does not compromise sperm fertility, and is widely applicable to a range of species. In this review, we will summarize the current state-of-the-art in sex preselection in domestic animals and some wildlife species using flow cytometric sperm-sorting of X from Y sperm based on DNA differences. PMID:22829354

Espinosa-Cervantes, Román; Córdova-Izquierdo, Alejandro

2012-12-01

43

Adaptive plasticity of mammalian sperm production in response to social experience  

PubMed Central

Sperm competition theory predicts that males should invest prudently in ejaculates according to levels of female promiscuity. Males may therefore be sensitive to cues in their social environment associated with sexual competition, and tailor investment in sperm production accordingly. We tested this idea experimentally for the first time, to our knowledge, in a mammal by comparing reproductive traits of male house mice (Mus musculus domesticus) that had experienced contrasting encounter regimes with potential sexual competitors. We found that daily sperm production and numbers of sperm in the caput epididymis were significantly higher in subjects that had experienced a high encounter rate of social cues from three other males compared to those that had experienced a low encounter rate of social cues from just one other male. Epididymal sperm counts were negatively correlated with the frequency of scent-marking behaviour across all males in our study, suggesting that investment in ejaculate production may be traded off against traits that function in gaining copulations, although there was no difference in overall levels of scent marking between treatment groups. We conclude that social experience-mediated phenotypic plasticity in mammalian spermatogenesis is likely to be adaptive under sperm competition, enabling males to balance the energetic costs and paternity-enhancing benefits of ejaculate production, and is a potentially widespread explanation for intraspecific variation in ejaculate expenditure.

Ramm, Steven A.; Stockley, Paula

2008-01-01

44

Fate of superfluous sperm products after vasectomy and in the normal male tract of the mouse  

Microsoft Academic Search

Summary. The progression of 3H-labelled spermatozoa (thymidine or arginine) was followed through the tracts of unilaterally vasectomized, bilaterally vasectomized, oligozoospermic (t6\\/tw5) and normal mice; the regional lymph nodes were also investi- gated. The same rate of sperm production and transport was found in normal and in vasectomized tracts, down to the corpus epididymidis; there was some delay in sperm- atozoa

C. L. R. Barratt; Jack Cohen

1986-01-01

45

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

46

Human sperm capacitation induced by biological fluids and progesterone, but not by NADH or NADPH, is associated with the production of superoxide anion.  

PubMed

Recent evidence indicated that human sperm capacitation is associated with an increased production of superoxide anion (O2.-). To further study the role and importance of O2.- in capacitation, we investigated whether the O2.- generation is a general feature of capacitating spermatozoa, irrespective of the inducer used, and is correlated with capacitation levels and increased tyrosine phosphorylation of two sperm proteins (p105/p81). We also studied the time courses of O2.- production and action. Percoll-washed human spermatozoa were incubated in Ham's F-10 medium, supplemented or not supplemented with various capacitation inducers and in the presence or absence of superoxide dismutase (SOD). Sperm capacitation was measured by induction of the acrosome reaction with lysophosphatidylcholine, O2.- production was measured by chemiluminescence, and tyrosine phosphorylation was measured by immunodetection after electrophoresis and western blotting of sperm proteins. Progesterone and ultrafiltrates of human fetal cord serum, follicular fluid, and seminal plasma individually promoted sperm generation of O2.-, tyrosine phosphorylation of p105/p81, and capacitation. Fetal cord serum ultrafiltrate triggered a fivefold higher O2.- production than the other inducers (1,700 +/- 300 and 300 to 400 mV/10s/8 x 10(6) cells, respectively), a phenomenon possibly associated with the higher potency of this fluid to promote sperm hyperactivation. The production of O2.- by spermatozoa was rapid and transient. SOD prevented sperm capacitation triggered by the inducers mentioned above, but only when SOD was added at the beginning of incubation, and not after 30 minutes, indicating that the O2.- initiates a chain of early events leading to sperm capacitation. NADH and NADPH (5 mM) triggered sperm capacitation and phosphorylation of p105/p81, but these processes were not prevented by SOD or catalase, nor were they associated with an increased O2.- production. Therefore, these cofactors appeared to act by mechanisms different from those used by the other inducers studied. The sperm enzyme responsible for the O2.- generation may be very different from the NADPH oxidase of neutrophils. PMID:9570746

de Lamirande, E; Harakat, A; Gagnon, C

1998-01-01

47

ZP-binding peptides identified via phage display stimulate production of sperm antibodies in dogs.  

PubMed

Zona pellucida (ZP) glycoproteins play a central role in sperm-oocyte binding and fertilization. Sperm protein sequences that are involved in sperm-ZP recognition and have an important role in fertilization represent attractive targets for development of contraceptive vaccines, yet are currently unknown. To identify peptide sequences that recognize and bind to ZP proteins, we developed a novel selection procedure from phage display libraries that utilizes intact oocytes surrounded by ZP proteins. The major advantage of this procedure is that ZP proteins remain in their native conformation unlike a selection protocol previously published that utilized solubilized ZP on artificial solid support. Several peptides of 7 and 12 amino acids with binding specificity to canine ZP proteins were identified. Four of them (LNSFLRS, SSWYRGA, YLPIYTIPSMVY, and NNQSPILKLSIH) plus a control ZP-binding peptide (YLPVGGLRRIGG) from the literature were synthesized and tested for antigenic properties in dogs. NNQSPILKLSIH peptide stimulated production of anti-peptide antibodies. These antibodies bind to the acrosomal region of the canine sperm cell, demonstrating ability to act as sperm antibodies. The identified ZP-binding peptides (mimicking sperm cell surface antigens) may be useful in the design of immunocontraceptive agents for dogs. PMID:20434854

Samoylova, Tatiana I; Cox, Nancy R; Cochran, Anna M; Samoylov, Alexandre M; Griffin, Brenda; Baker, Henry J

2010-07-01

48

The role of androgens in species recognition and sperm production in Atlantic mollies (Poecilia mexicana).  

PubMed

Much is known about the role of hormones in the regulation of vertebrate mating behavior, including receptivity, and several components of mate choice. Hormones may modulate reproductive behavior in such a way to increase or decrease the individual's motivation, and therefore hormones may be important in mediating behavior associated with reproductive isolation. The mating complex of the all female gynogenetic Amazon mollies, Poecilia formosa, and their parental species (sailfin mollies, P. latipinna, and Atlantic mollies, P. mexicana) is a model system for studying ultimate mechanisms of species recognition. However, proximate mechanisms, such as variation in hormone levels, and the effect of hormones on sperm production have not been extensively examined. We predict that one or more of the sex steroid hormones in teleost fish (11-ketotestosterone (KT), testosterone (T), and estradiol (E)) will play a role in species recognition (during mate choice and/or sperm priming) for Atlantic mollies (the maternal parental species) that are sympatric with Amazon mollies. We sequentially paired male Atlantic mollies with female conspecifics and Amazon mollies and obtained water-borne hormone samples before and after mating for all fish. We measured circulating KT, T, and E from the water samples. Although we did not find an overall KT response to mating with conspecifics as has been found previously in sailfin mollies, male Atlantic mollies that mated more with conspecific females had lower postmating T levels. Additionally, males attempted to mate more with conspecific females that had lower postmating E levels, but attempted to mate more with Amazon mollies that had higher postmating KT levels. We also examined the effect of KT on sperm priming (a mechanism of premating mate choice), and found that KT levels of male Atlantic mollies prior to mating are correlated with the sperm priming response when males were paired with conspecific females, but this correlation was not found when males were paired with Amazon mollies. Our results indicate that male mating behavior is affecting or responding to both male and female hormones, but that the hormones alone are not playing a role in species recognition. Male Atlantic mollies may not discriminate against Amazon mollies as strongly as male sailfin mollies because Amazon mollies resemble their maternal parental species more than their paternal species. PMID:22061426

Gabor, Caitlin R; Aspbury, Andrea S; Ma, Jacqueline; Nice, Chris C

2012-02-01

49

Plastic responses of male Drosophila melanogaster to the level of sperm competition increase male reproductive fitness  

PubMed Central

Evolutionary and plastic responses by males to the level of sperm competition (SC) are reported across widespread taxa, but direct tests of the consequences for male reproductive success in a competitive context are lacking. We varied male perception of SC to examine the effect on male competitive reproductive success and to test whether the outcomes were as predicted by theory. Exposure to rival males prior to mating increased a male's ejaculate investment (measured as mating duration); by contrast, exposure to rival males in the mating arena decreased mating duration. The results therefore suggested that SC intensity is important in shaping male responses to SC in this system, although the patterns were not strictly in accord with existing theory. We then tested whether males that responded to the level of SC had higher reproductive fitness in a competitive context. We found that males kept with rivals prior to mating again mated for longer; furthermore, they achieved significantly higher paternity share regardless of whether they were the first or second males to mate with a female. The plastic strategies employed by males therefore resulted in significantly increased reproductive success in a competitive context, even following subsequent rematings in which the majority of sperm were displaced.

Bretman, Amanda; Fricke, Claudia; Chapman, Tracey

2009-01-01

50

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

51

Anopheles arabiensis sperm production after genetic manipulation, dieldrin treatment, and irradiation.  

PubMed

The use of the sterile insect technique relies on the release of sterilized mass-reared male insects which, before field releases, endure several unnatural treatments. In the case of Anopheles arabiensis (Patton) sterile insect technique program in Sudan, the genetic background of the original strain was first changed to create a genetic sexing strain that is based on a dieldrin-resistant mutation. Secondly, the eggs of the genetic sexing strain require treatment with dieldrin to allow complete elimination of female L1 larvae to enable the release of males only. Finally, male mosquitoes receive an irradiation dose of 70 Gy as pupae for sterilization. The effects of these treatments on sperm production were tested separately and in combination. Irradiation alone significantly decreased the initial sperm number and prevented new sperm production. However, the dieldrin treatment, aimed at eliminating females, appears to have an unexpected radioprotectant effect. PMID:23540119

Damiens, D; Vreysen, M J B; Gilles, J R L

2013-03-01

52

Sperm competition, male prudence and sperm-limited females  

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 J. G. Gage; Geoffrey A. Parker

2002-01-01

53

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.

Alvarez-Gallardo, Horacio; Kjelland, Michael E.; Moreno, Juan F.; Welsh, Thomas H.; Randel, Ronald D.; Lammoglia, Miguel A.; Perez-Martinez, Mario; Lara-Sagahon, Alma V.; Esperon-Sumano, A. Enrique; Romo, Salvador

2013-01-01

54

Gamete therapeutics: recombinant protein adsorption by sperm for increasing fertility via artificial insemination.  

PubMed

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

55

The Effect of Orally Administered L-carnitine on Testis Tissue, Sperm Parameters and Daily Sperm Production in Adult Mice  

Microsoft Academic Search

Introduction: The purpose of this study was to evaluate body and testis weight, testis tis- sue, counts, motility, viability, morphology, and chromatin quality of epididymal sperm, as well as the testicular spermatid number (TSN) per gram of testis, and daily sperm produc- tion (DSP) in L-carnitine treated mice. Materials and Methods: In the present study, adult male NMRI mice (mean

Zohre Zare; Hosein Eimani; Moslem Mohammadi; Mahmood Mofid; Hosein Dashtnavard

56

Direct action of endocrine disrupting chemicals on human sperm.  

PubMed

Synthetic endocrine disrupting chemicals (EDCs), omnipresent in food, household, and personal care products, have been implicated in adverse trends in human reproduction, including infertility and increasing demand for assisted reproduction. Here, we study the action of 96 ubiquitous EDCs on human sperm. We show that structurally diverse EDCs activate the sperm-specific CatSper channel and, thereby, evoke an intracellular Ca(2+) increase, a motility response, and acrosomal exocytosis. Moreover, EDCs desensitize sperm for physiological CatSper ligands and cooperate in low-dose mixtures to elevate Ca(2+) levels in sperm. We conclude that EDCs interfere with various sperm functions and, thereby, might impair human fertilization. PMID:24820036

Schiffer, Christian; Müller, Astrid; Egeberg, Dorte L; Alvarez, Luis; Brenker, Christoph; Rehfeld, Anders; Frederiksen, Hanne; Wäschle, Benjamin; Kaupp, U Benjamin; Balbach, Melanie; Wachten, Dagmar; Skakkebaek, Niels E; Almstrup, Kristian; Strünker, Timo

2014-07-01

57

The relationship of increased susceptibility of sperm DNA to denaturation and fertility in the stallion  

Microsoft Academic Search

The relationship between fertility and susceptibility of sperm DNA to denaturation was determined in a group of 84 actively breeding, clinically fertile stallions. Susceptibility of DNA to denaturation was determined using the sperm chromatin structure assay (SCSA). The SCSA measures, mean of alpha-t (mean?t), standard deviation of alpha-t (SD?t), and the COMP of alpha-t (cells outside the main population)] were

C. C Love; R. M Kenney

1998-01-01

58

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

59

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

60

Activation of sea-urchin sperm motility is accompanied by an increase in the creatine kinase exchange flux.  

PubMed Central

The kinetics of the creatine kinase (CK) reaction were studied in suspensions of quiescent and active, intact sea-urchin spermatozoa in artificial seawater, using 31P-NMR magnetization transfer. In inactive sperm, no CK-mediated exchange flux was detected, whereas in activated motile sperm, the forward pseudo-first-order rate constant was 0.13+/-0.04 s-1 at 10 degrees C, corresponding to a steady-state CK flux of 3.1+/-0.5 mM.s-1. Intracellular pH shifted from 6.6+/-0.1 to 7.6+/-0.1 upon activation. The phosphocreatine (PCr)/ATP and PCr/Pi ratios were only marginally reduced in activated sperm, whereas the estimated cytosolic free ADP concentration increased remarkably from 9 microM in quiescent, to 114 microM in activated spermatozoa. The elevation of CK flux upon sperm activation is discussed in the light of the proposition that in sea-urchin spermatozoa, which are fuelled entirely by oxidative phosphorylation, high-energy phosphate transport is mediated by a 'CK/PCr shuttle'.

Dorsten, F A; Wyss, M; Wallimann, T; Nicolay, K

1997-01-01

61

Common variants in mismatch repair genes associated with increased risk of sperm DNA damage and male infertility  

PubMed Central

Background The mismatch repair (MMR) pathway plays an important role in the maintenance of the genome integrity, meiotic recombination and gametogenesis. This study investigated whether genetic variations in MMR genes are associated with an increased risk of sperm DNA damage and male infertility. Methods We selected and genotyped 21 tagging single nucleotide polymorphisms (SNPs) in five MMR genes (MLH1, MLH3, PMS2, MSH4 and MSH5) using the SNPstream 12-plex platform in a case-control study of 1,292 idiopathic infertility patients and 480 fertile controls in a Chinese population. Sperm DNA damage levels were detected with the Tdt-mediated dUTP nick end labelling (TUNEL) assay in 450 cases. Fluorescence resonance energy transfer (FRET) and co-immunoprecipitation techniques were employed to determine the effects of functional variants. Results One intronic SNP in MLH1 (rs4647269) and two non-synonymous SNPs in PMS2 (rs1059060, Ser775Asn) and MSH5 (rs2075789, Pro29Ser) seem to be risk factors for the development of azoospermia or oligozoospermia. Meanwhile, we also identified a possible contribution of PMS2 rs1059060 to the risk of male infertility with normal sperm count. Among patients with normal sperm count, MLH1 rs4647269 and PMS2 rs1059060 were associated with increased sperm DNA damage. Functional analysis revealed that the PMS2 rs1059060 can affect the interactions between MLH1 and PMS2. Conclusions Our results provide evidence supporting the involvement of genetic polymorphisms in MMR genes in the aetiology of male infertility.

2012-01-01

62

Increased expression of ERp57 in rat oocytes during meiotic maturation is associated with sperm-egg fusion.  

PubMed

Oocyte meiotic maturation is a developmental transition that starts during germinal-vesicle breakdown and ends at the arrest in metaphase of meiosis II. This transition is associated with changes to both the proteins that are synthesized and the abundance/distribution of post-translational modifications that are crucial for subsequent fertilization and embryogenesis. Here, we isolated and cultured rat oocytes in vitro during both metaphase of meiosis I (MI) and meiosis II (MII) stages, respectively, and then compared their proteomic profiles by high-resolution, two-dimensional gel electrophoresis (2DE) followed by mass spectrometry. We found that the expression of five proteins was up-regulated while six proteins were down-regulated when comparing MI to MII oocytes. The expression of ERp57, an endoplasmic reticulum chaperone, underwent a dramatic increase between MI and MII oocytes, and became concentrated in a dome-shaped area of the cell surface within the microvillar region. A similar profile was observed during spermatogenesis, and sperm ERp57 eventually localized to the head and flagellum surfaces, finally ending in the equatorial region of acrosome-reacted sperm. Given the localization pattern, we tested and found that a polyclonal antiserum created against recombinant rat ERp57 significantly inhibited spermatozoa from penetrating zona pellucida-free oocytes without affecting either sperm motility or the acrosome reaction. These results indicate that ERp57 expression on oocytes, and possibly sperm, plays an important physiological role during sperm-egg fusion. Mol. Reprod. Dev. 81: 315-325, 2014. © 2014 Wiley Periodicals, Inc. PMID:24415168

Liu, Yue; Zhu, Yemin; Wu, Xiaohui; Li, Yandong; Guo, Qiangsu; Li, Weiping; Ding, Zhide

2014-04-01

63

Testosterone rapidly increases ejaculate volume and sperm density in competitively breeding goldfish through an estrogenic membrane receptor mechanism.  

PubMed

The social environment can have dramatic influences on reproductive behavior and physiology in many vertebrate species. In males, interactions with conspecifics affect physiological processes that increase an individual's ability to compete for mates. For example, in some species, males rapidly adjust the number of sperm they ejaculate in response to sociosexual cues from male and female conspecifics, however, little is known about the physiological mechanisms mediating this behavior. In goldfish, as in many vertebrates, social cues also drive transient surges of the gonadal hormone testosterone (T), which induces rapid effects on cellular processes via its conversion to estradiol (E2). We asked whether such surges rapidly influence ejaculate quantity and quality by experimentally manipulating peripheral levels of T and E2. We show that male goldfish injected with T increased ejaculate (milt) volume and sperm density within just 1 hr. Furthermore, increases in expressible milt were dependent on the conversion of T to E2 by the enzyme aromatase, required activation of estrogen receptors ? and ?, and were also elicited by BSA-conjugated E2, which acts on cell membrane-bound estrogen receptors. Together, these findings represent a novel steroid mechanism for the social modulation of sperm output over the short time scales that characterize reproductive encounters, and thus demonstrate a previously undescribed functional consequence of rapid estrogen signaling mechanisms. We suggest that such mechanisms may play a critical role in the enhancement of physiological and behavioral processes that increase reproductive success in competitive mating contexts. PMID:22613707

Mangiamele, Lisa A; Thompson, Richmond R

2012-07-01

64

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

Microsoft Academic Search

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

Mary Hagedorn; Virginia L. Carter

2011-01-01

65

No increase in sperm DNA damage and seminal oxidative stress in patients with idiopathic infertility  

Microsoft Academic Search

The most common cause of male infertility is idiopathic. Standard investigations reveal no abnormality in such cases. The aim of the study was to investigate the levels of sperm DNA damage and seminal oxidative stress and their relationships with idiopathic infertility. The study included 30 normozoospermic infertile men seeking infertility treatment and 20 fertile donors. Semen analysis was performed according

Fatma Ferda Verit; Ayhan Verit; Abdurrahim Kocyigit; Halil Ciftci; Hakim Celik; Mete Koksal

2006-01-01

66

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

67

The Beltsville sperm sexing technology: high-speed sperm sorting gives improved sperm output for in vitro fertilization and AI.  

PubMed

The Beltsville sperm sexing technology is currently the only effective means of altering the sex ratio of offspring in livestock. The method is based on the flow-cytometric separation of X- and Y-chromosome-bearing sperm based on X/Y DNA content difference. It is an effective means of producing progeny of predetermined sex in cattle, swine, sheep, and laboratory animals. The method involves treating sperm with a DNA-binding fluorochrome, Hoechst 33342, and flow-cytometrically sorting them into separate X and Y populations that can subsequently be used for surgical intratubal or intrauterine insemination, deep-uterine insemination, regular artificial insemination in some cases, in vitro fertilization to produce sexed embryos for transfer, and intracytoplasmic sperm injection of ova. Skewed sex ratios of 85 to 95% of one sex or the other have been repeatably achieved in most species. The method has been used worldwide to produce several hundred morphologically normal animal offspring of the predicted sex. It has also been validated in the laboratory using DNA reanalysis of the sorted sperm populations and by fluorescence in situ hybridization and PCR of individual sperm. We developed a new orienting nozzle that we have fitted to both conventional and high-speed cell sorters that have been modified for sperm sorting. Recently we completed the adaptation of the new orienting nozzle to a Cytomation MoFlo high-speed cell sorter modified for sperm. This adaptation of the nozzle has increased the overall production rate of sorted X and Y sperm from about .35 million/h to 5 or 6 million sperm/h (each population). Calves have been born from cows artificially inseminated using conventional technique and sexed sperm. In addition, numerous litters of pigs have been born after transfer of embryos produced from X or Y sorted sperm. PMID:15526798

Johnson, L A; Welch, G R; Rens, W

1999-01-01

68

Bacteria in bovine semen can increase sperm DNA fragmentation rates: A kinetic experimental approach  

Microsoft Academic Search

Cryopreserved straws of semen (n=228) from Holstein bulls (n=47) were examined for bacterial presence and sperm DNA fragmentation (SDF) dynamics. Commercial semen doses (representing six ejaculates per individual) were randomly selected from a bull stud in Spain. The dynamics of SDF were assessed after thawing (T0) and at 4, 24, 48, 72 and 96h of incubation at 37°C, using the

C. González-Marín; R. Roy; C. López-Fernández; B. Diez; M. J. Carabaño; J. L. Fernández; M. E. Kjelland; J. F. Moreno; J. Gosálvez

2011-01-01

69

Electroejaculation increases low molecular weight proteins in seminal plasma modifying sperm quality in Corriedale rams.  

PubMed

This study was conducted to evaluate the effect of seminal collection method (artificial vagina or electroejaculation) on the protein composition of seminal plasma and sperm quality parameters in Corriedale rams. To address this question, we assessed the effect of seminal collection method on motility, plasma membrane integrity and functionality, mitochondrial functionality and the decondensation state of nuclear chromatin in sperm cells. Volume, pH, osmolarity, protein concentration, total protein content and protein profile using sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and 2-D polyacrylamide electrophoresis of seminal plasma collected with artificial vagina and electroejaculation were also analysed. The main findings from this study were that ejaculates obtained with electroejaculation had (i) a higher number of spermatozoa with intact plasma membrane and functional mitochondria and (ii) a higher proportion of seminal plasma, total protein content and relative abundance of low molecular weight proteins than ejaculates obtained with artificial vagina. Five of these proteins were identified by mass spectrometry: binder of sperm 5 precursor; RSVP14; RSVP22; epididymal secretory protein E1 and clusterin. One protein spot with molecular weight of approximately 31 kDa and isoelectric point of 4.8 was only found in the seminal plasma from electroejaculation. PMID:24494601

Ledesma, A; Manes, J; Cesari, A; Alberio, R; Hozbor, F

2014-04-01

70

Embryo production after in vitro fertilization with frozen-thawed, sex-sorted, re-frozen-thawed bull sperm.  

PubMed

The objective of this study was to determine the in vitro fertilizing capacity of bull sperm derived from fresh or frozen samples and subjected to sex sorting and re-cryopreservation. Four sperm types were assessed for their ability to fertilize and sustain early embryo development in vitro. Semen from three Bos taurus bulls of different breeds (Jersey, Holstein and Simmental) was collected and either sorted immediately and then frozen (SF) or frozen for later sorting. Frozen sperm destined for sorting were thawed, sex-sorted, and re-frozen (FSF) or thawed, sex-sorted (FS), and used immediately for in vitro fertilization (IVF). Frozen-thawed nonsorted semen from the same ejaculate was used as a control. Oocytes from donor cows were aspirated via ovum pick-up and matured in vitro prior to IVF and culture. On average, 19.0+/-1.7 (mean+/-SEM) oocytes were aspirated per donor cow, of which 74.4+/-2.2% were selected for maturation. The proportion of cleaved embryos (Day 3) did not differ between sperm groups (P=0.91). Likewise, IVF with FSF sperm resulted in similar Day 7 blastocyst rates (as a percentage of total oocytes) as those of control, SF, and FS sperm (FSF, 34.5+/-4.7; control, 32.2+/-4.6; SF, 35.9+/-4.8; and FS, 26.9+/-4.1%; P=0.23). These encouraging results show that frozen-thawed sex-sorted sperm may be re-frozen and used for in vitro embryo production with similar blastocyst production as that of nonsorted frozen-thawed and sex-sorted frozen-thawed sperm. PMID:19853289

Underwood, S L; Bathgate, R; Pereira, D C; Castro, A; Thomson, P C; Maxwell, W M C; Evans, G

2010-01-01

71

Regulation of diacylglycerol production and protein kinase C stimulation during sperm- and PLC?-mediated mouse egg activation  

PubMed Central

Background information. At fertilization in mammalian eggs, the sperm induces a series of Ca2+ oscillations via the production of inositol 1,4,5-trisphosphate. Increased inositol 1,4,5-trisphosphate production appears to be triggered by a sperm-derived PLC? (phospholipase C-?) that enters the egg after gamete fusion. The specific phosphatidylinositol 4,5-bisphosphate hydrolytic activity of PLC? implies that DAG (diacylglycerol) production, and hence PKC (protein kinase C) stimulation, also occurs during mammalian egg fertilization. Fertilization-mediated increase in PKC activity has been demonstrated; however, its precise role is unclear. Results. We investigated PLC?- and fertilization-mediated generation of DAG in mouse eggs by monitoring plasma-membrane translocation of a fluorescent DAG-specific reporter. Consistent plasma-membrane DAG formation at fertilization, or after injection of physiological concentrations of PLC?, was barely detectable. However, when PLC? is overexpressed in eggs, significant plasma-membrane DAG production occurs in concert with a series of unexpected secondary high-frequency Ca2+ oscillations. We show that these secondary Ca2+ oscillations can be mimicked in a variety of situations by the stimulation of PKC and that they can be prevented by PKC inhibition. The way PKC leads to secondary Ca2+ oscillations appears to involve Ca2+ influx and the loading of thapsigargin-sensitive Ca2+ stores. Conclusions. Our results suggest that overproduction of DAG in PLC?-injected eggs can lead to PKC-mediated Ca2+ influx and subsequent overloading of Ca2+ stores. These results suggest that DAG generation in the plasma membrane of fertilizing mouse eggs is minimized since it can perturb egg Ca2+ homoeostasis via excessive Ca2+ influx.

Yu, Yuansong; Halet, Guillaume; Lai, F. Anthony; Swann, Karl

2008-01-01

72

Surrogate production of eggs and sperm by intrapapillary transplantation of germ cells in cytoablated adult fish.  

PubMed

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

73

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.

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

2014-01-01

74

Coevolution of non-fertile sperm and female receptivity in a butterfly  

PubMed Central

Sexual conflict can promote rapid evolution of male and female reproductive traits. Males of many polyandrous butterflies transfer nutrients at mating that enhances female fecundity, but generates sexual conflict over female remating due to sperm competition. Butterflies produce both normal fertilizing sperm and large numbers of non-fertile sperm. In the green-veined white butterfly, Pieris napi, non-fertile sperm fill the females' sperm storage organ, switching off receptivity and thereby reducing female remating. There is genetic variation in the number of non-fertile sperm stored, which directly relates to the female's refractory period. There is also genetic variation in males' sperm production. Here, we show that females' refractory period and males' sperm production are genetically correlated using quantitative genetic and selection experiments. Thus selection on male manipulation may increase the frequency of susceptible females to such manipulations as a correlated response and vice versa.

Wedell, Nina; Wiklund, Christer; Bergstrom, Jonas

2009-01-01

75

A comparative study of sperm production in two species of Australian arid zone rodents (Pseudomys australis, Notomys alexis) with marked differences in testis size.  

PubMed

The plains rat, Pseudomys australis, and the spinifex hopping mouse, Notomys alexis, show marked differences in the size of their testes and in the number of spermatozoa within the epididymides. In the present study, the dynamics of sperm production and the duration of sperm transit along the male excurrent ducts were compared between these two species. The durations of the cycle of the seminiferous epithelium, spermatogenesis and sperm transit were determined by tracking cells using autoradiography after [(3)H]thymidine incorporation. Daily sperm production was determined from counts of testicular spermatids after homogenization and further estimates of sperm transit were obtained by dividing sperm reserves within the various regions of the extratesticular ducts by the daily sperm production of the attached testis. In the plains rat, the mean duration of the cycle of the seminiferous epithelium was 11.2 days, the duration of spermatogenesis was 45 days, daily sperm production was 2.6 x 10(7) spermatozoa per gram of testis and epididymal transit of spermatozoa took approximately 9 days (caput 0.8 days; corpus 1.5 days; cauda 6.5 days). In contrast, in the hopping mouse, the mean duration of the cycle of the seminiferous epithelium was 14 days, the duration of spermatogenesis was 56 days and daily sperm production per gram of testis was < 1.0 x 10(7). Epididymal transit of spermatozoa was completed in about 4 days (caput + corpus < 1 day; cauda 3 days); however, spermatozoa may be stored for an additional 1.5-2.0 days in the vas deferens. These results indicate that, in addition to small testes, the hopping mouse shows a low efficiency of sperm production, a relatively long duration of spermatogenesis and rapid passage of spermatozoa through the epididymis, all of which contribute to low epididymal sperm counts. These data are considered in relation to interspecific differences in sperm competition. PMID:11226048

Peirce, E J; Breed, W G

2001-02-01

76

[How to increase food production?].  

PubMed

Pressure of population on cultivable land, serious soil erosion, and low productivity due to scarcity of inputs have hampered efforts to provide an adequate diet for the population of Rwanda. Until the present, production has increased about as rapidly as population, but Rwanda is not totally self-sufficient in food, future climatic conditions may be less favorable than those of the past, technical and resource constraints are likely to increase, and little new land will be available for cultivation. Between 1970-80, hectares devoted to bananas and beans have increased considerably, but the marginal nature of much new land has seriously lowered productivity. Sweet potatoes are more extensively grown but their productivity is limited, and productivity of manioc has stagnated despite efforts to increase it. Peas are less frequently cultivated because the fallow land on they they are grown has almost disappeared due to population pressure. Agriculture in Rwanda has always been associated with herding, but population pressure is eliminating pastureland. Firewood for cooking is also becoming more scarce and reforestation is not proceeding rapidly enough to fill projected demand. Between 1978-80 and the year 2000, preliminary goals are to increase production in tons from 2,005,900 to 3,375,000 for bananas, from 177,400 to 330,000 for beans, from 15,200 to 45,500 for ground nuts, from 4000 to 25,000 for soybeans, from 174,800 to 288,000 for sorghum, from 81,300 to 250,000 for maize, from 3700 to 45,000 for rice, from 837,100 to 2,148,000 for sweet potatoes, from 506,600 to 1,200,000 for manioc, and from 216,000 to 600,000 for potatoes. Reaching these goals will require doubling of overall productivity per hectare. Different strategies will be required for increasing the yields of the principal crops. Priority should be given to developing strains of beans that will grow well in the poor soils, dry or cold regions, and acidic soils where they are usually planted in Rwanda. Beans requiring less labor-intensive cultivation and able to grow in association with other crops or under banana trees are needed. The new varieties should be resistent to disease and pests. Bananas, with an annual production of over 2 million tons, are the most important crop in Rwanda, but 80-90% is used for beer, an important indicator of family wealth and symbolic object in social relations. The average yield of bananas declined by 19% between 1970-80. 3 very productive varieties of table bananas have been introduced recently, but research is needed in different ecologic regions of Rwanda focusing on cultivation of bananas in association with other crops, improved varieties of bananas, and better cultivation methods. Research should also be directed toward developing the best varieties of high, medium, and low altitude sorghum, the traditional cereal crop, of maize and of sweet potatoes, the 2nd most important crop, as well as toward identifying the best cultivation methods for each. PMID:12267714

Gahamanyi, L

1984-12-01

77

Effect of heparin on cleavage rates and embryo production with four bovine sperm preparation protocols  

Microsoft Academic Search

Heparin is often added to fertilization media to induce sperm capacitation. However, recent observations from the bovine IVF industry have indicated that heparin may not be necessary to induce sperm capacitation when cryopreserved bovine sperm are separated through Percoll gradients. The objective of these studies was to determine if the addition of heparin to fertilization media was required following separation

J. O. B Mendes; P. D Burns; J. F De La Torre-Sanchez; G. E Seidel

2003-01-01

78

The Effect of Ambient Air Pollution on Sperm Quality  

PubMed Central

Background Research has suggested an association with ambient air pollution and sperm quality. Objectives We investigated the effect of exposure to ozone (O3) and particulate matter < 2.5 ?m in aerodynamic diameter (PM2.5) on sperm quality. Methods We reexamined a previous cohort study of water disinfection by-products to evaluate sperm quality in 228 presumed fertile men with different air pollution profiles. Outcomes included sperm concentration, total sperm per ejaculate (count), and morphology, as well as DNA integrity and chromatin maturity. Exposures to O3 and PM2.5 were evaluated for the 90–day period before sampling. We used multivariable linear regression, which included different levels of adjustment (i.e., without and with season and temperature) to assess the relationship between exposure to air pollutants during key periods of sperm development and adverse sperm outcomes. Results Sperm concentration and count were not associated with exposure to PM2.5, but there was evidence of an association (but not statistically significant) with O3 concentration and decreased sperm concentration and count. Additionally, a significant increase in the percentage of sperm cells with cytoplasmic drop [? = 2.64; 95% confidence interval (CI), 0.21–5.06] and abnormal head (? = 0.47; 95% CI, 0.03–0.92) was associated with PM2.5 concentration in the base model. However, these associations, along with all other sperm outcomes, were not significantly associated with either pollutant after controlling for season and temperature. Overall, although we found both protective and adverse effects, there was generally no consistent pattern of increased abnormal sperm quality with elevated exposure to O3 or PM2.5. Conclusions Exposures to O3 or PM2.5 at levels below the current National Ambient Air Quality Standards were not associated with statistically significant decrements in sperm outcomes in this cohort of fertile men. However, some results suggested effects on sperm concentration, count, and morphology.

Hansen, Craig; Luben, Thomas J.; Sacks, Jason D.; Olshan, Andrew; Jeffay, Susan; Strader, Lillian; Perreault, Sally D.

2010-01-01

79

Competition between the sperm of a single male can increase the evolutionary rate of haploid expressed genes.  

PubMed

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

2013-07-01

80

Production of Diabetic Offspring Using Cryopreserved Epididymal Sperm by In Vitro Fertilization and Intrafallopian Insemination Techniques in Transgenic Pigs  

PubMed Central

Abstract Somatic cell nuclear transfer (SCNT) is a useful technique for creating pig strains that model human diseases. However, production of numerous cloned disease model pigs by SCNT for large-scale experiments is impractical due to its complexity and inefficiency. In the present study, we aimed to establish an efficient procedure for proliferating the diabetes model pig carrying the mutant human hepatocyte nuclear factor-1? gene. A founder diabetes transgenic cloned pig was generated by SCNT and treated with insulin to allow for normal growth to maturity, at which point epididymal sperm could be collected for cryopreservation. In vitro fertilization and intrafallopian insemination using the cryopreserved epididymal sperm resulted in diabetes model transgenic offspring. These results suggest that artificial reproductive technology using cryopreserved epididymal sperm could be a practical option for proliferation of genetically modified disease model pigs.

UMEYAMA, Kazuhiro; HONDA, Kasumi; MATSUNARI, Hitomi; NAKANO, Kazuaki; HIDAKA, Tatsuro; SEKIGUCHI, Keito; MOCHIZUKI, Hironori; TAKEUCHI, Yasuhiro; FUJIWARA, Tsukasa; WATANABE, Masahito; NAGAYA, Masaki; NAGASHIMA, Hiroshi

2013-01-01

81

PUBERTY IN BEEF BULLS: HORMONE CONCENTRATIONS, GROWTH, TESTICULAR DEVELOPMENT, SPERM PRODUCTION AND SEXUAL AGGRESSIVENESS IN BULLS OF DIFFERENT BREEDS I  

Microsoft Academic Search

SUMMARY Postweaning growth and pubertal traits were studied in Hereford, Angus, Red Poll, Brown Swiss, Hereford-Angus crossbred (HXA) and Angus-Hereford crossbred (AX H) bulls from 7 through 13 months of age. Pubertal factors characterized included body weight, testicular size, hormone concentrations, sexual aggressive- ness and sperm production. Puberty was de- fined as the age at which a bull first produced

D. D. Lunstra; J. J. Ford; S. E. Echternkamp

2010-01-01

82

Evaluation of activation treatments for blastocyst production and birth of viable calves following bovine intracytoplasmic sperm injection  

Microsoft Academic Search

The objective of this study was to compare the effectiveness of different methods of bovine oocyte activation following intracytoplasmic sperm injection (ICSI) in terms of oocyte cleavage and blastocyst rates, and calf production. Oocytes were harvested, post mortem, from the ovaries of Japanese Black heifers or cows. ICSI was carried out using a piezo-electric actuator. The injected or sham-injected oocytes

T. Oikawa; N. Takada; T. Kikuchi; T. Numabe; M. Takenaka; T. Horiuchi

2005-01-01

83

New assays for detection and localization of endogenous lipid peroxidation products in living boar sperm after BTS dilution or after freeze-thawing.  

PubMed

Reactive oxygen species have been implicated in sperm aberrations causing multiple pathologies including sub- and infertility. Freeze/thawing of sperm samples is routinely performed in the cattle breeding industries for semen storage prior to artificial insemination but unusual in porcine breeding industries as semen dilution and storage at 17 degrees C is sufficient for artificial insemination within 2-3 days. However, longer semen storage requires cryopreservation of boar semen. Freeze/thawing procedures induce sperm damage and induce reactive oxygen species in mammalian sperm and boar sperm seems to be more vulnerable for this than bull sperm. We developed a new method to detect reactive oxygen species induced damage at the level of the sperm plasma membrane in bull sperm. Lipid peroxidation in freshly stored and frozen/thawed sperm cells was assessed by mass spectrometric analysis of the main endogenous lipid classes, phosphatidylcholine and cholesterol and by fluorescence techniques using the lipid peroxidation reporter probe C11-BODIPY(581/591). Peroxidation as reported by the fluorescent probe, clearly corresponded with the presence of hydroxy- and hydroperoxyphosphatidylcholine in the sperm membranes, which are early stage products of lipid peroxidation. This allowed us, for the first time, to correlate endogenous lipid peroxidation with localization of this process in the living sperm cells. Cytoplasmatic droplets in incompletely matured sperm cells were intensely peroxidized. Furthermore, lipid peroxidation was particularly strong in the mid-piece and tail of frozen/thawed spermatozoa and significantly less intense in the sperm head. Induction of peroxidation in fresh sperm cells with the lipid soluble reactive oxygen species tert-butylhydroperoxide gave an even more pronounced effect, demonstrating antioxidant activity in the head of fresh sperm cells. Furthermore, we were able to show using the flow cytometer that spontaneous peroxidation was not a result of cell death, as only a pronounced subpopulation of living cells showed peroxidation after freeze-thawing. Although the method was established on bovine sperm, we discuss the importance of these assays for detecting lipid peroxidation in boar sperm cells. PMID:15626411

Brouwers, Jos F; Silva, Patricia F N; Gadella, Barend M

2005-01-15

84

Duration of spermatogenesis and daily sperm production in the jaguar (Panthera onca).  

PubMed

The jaguar, like most wild felids, is an endangered species. Since there are few data regarding reproductive biology for this species, our main goal was to investigate basic aspects of the testis and spermatogenesis. Four adult male jaguars were utilized; to determine the duration of spermatogenesis, two animals received an intratesticular injection of H(3)-thymidine. Mean (+/-SEM) testis weight and the gonadosomatic index were 17.7+/-2.2g and 0.05+/-0.01%, respectively, whereas the seminiferous tubules and the Leydig cells volume density were 74.7+/-3.8 and 16.7+/-1.6%. Eight stages of spermatogenesis were characterized, according to the tubular morphology system and acrosome development. Each spermatogenic cycle and the entire spermatogenic process (based on 4.5 cycles) lasted approximately 12.8+/-0.01 and 57.7+/-0.07 d. The number of Sertoli and Leydig cells per gram of testis was 29+/-4 x 10(6) and 107+/-12 x 10(6). Based on the number of round spermatids per pachytene spermatocyte (2.8+/-0.3:1; meiotic index); significant cell loss (30%) occurred during the two meiotic divisions. There were approximately eight spermatids for each Sertoli cell (Sertoli cell efficiency), whereas the daily sperm production per gram of testis was 16.9+/-1.2 x 10(6). We expect that in the near future, the knowledge obtained in the present investigation will facilitate, utilizing germ cell transplantation, preservation of the germinal epithelium and the ability to generate sperm from jaguars in testes of domestic cats. PMID:18672284

Costa, G M J; Chiarini-Garcia, H; Morato, R G; Alvarenga, R L L S; França, L R

2008-10-15

85

A common protamine 1 promoter polymorphism (-190 C->A) correlates with abnormal sperm morphology and increased protamine P1/P2 ratio in infertile patients.  

PubMed

It is known that targeting the protamine 1 gene in mice leads to infertility, abnormal chromatin packaging, and abnormal sperm morphology. Because many infertile patients also have an abnormal sperm morphology and chromatin packaging, the human protamine 1 gene (PRM1) is an important candidate to screen for potential mutations. In this work, we have screened the PRM1 gene in search of potential mutations and determined the sperm morphology and the ratio between protamine 1 and protamine 2 (P1/P2 ratio). Direct sequencing of the PRM1 promoter led to the identification of a common single-nucleotide polymorphism (SNP; -190 C-->A). The -190 AA genotype was detected at a higher frequency (13.8%) in patients with markedly altered sperm morphology (A change was also consistently higher (.331) in infertile patients with a markedly altered morphology compared with population controls (.178; P < .01). Additionally, we have determined that the P1/P2 ratio is significantly increased in patients with the PRM1 -190 AA genotype compared with patients with the CA or CC genotypes (P = .006, Mann-Whitney). These findings indicate that the common PRM1 -190 C-->A polymorphism identified is associated with abnormal sperm head morphology and abnormal P1/P2 ratio in infertile patients. PMID:18390561

Gázquez, Cristina; Oriola, Josep; de Mateo, Sara; Vidal-Taboada, José M; Ballescà, José Luis; Oliva, Rafael

2008-01-01

86

Effect of Supplementation with Agro-industrial By-products and Khat (Catha edulis) leftovers on testicular growth and sperm production in Ogaden bucks.  

PubMed

The aim of this study was to characterize growth and sperm production parameters in Ogaden bucks fed a basal diet of hay and supplemented with agro-industrial by-products and Khat leftovers in Ethiopia. Thirty-five bucks with a mean (+/-SD) initial live body weight (BW) of 15.5 +/- 1.5 kg were randomly assigned to one of four dietary treatments for a period of 13 weeks. Treatments consisted of native hay fed ad libitum (control; C), native hay supplemented with a 1% of BW agro-industrial by-products (treatment 1; T1), native hay supplemented with Khat (Catha edulis) leftovers at a rate of 1% of BW (treatment 2; T2) and Khat leftovers fed ad libitum (treatment 3; T3). Bucks fed on T1-T3 had higher BW, body condition score, scrotal circumference (SC), testicular width and testicular length, compared to controls (P < 0.05). Also, bucks in T1-T3 had higher sperm progressive motility, sperm concentration per ml and total number of spermatozoa per ejaculate compared to controls (P < 0.05). Between treatments, bucks in T3 recorded the highest BW (17.2 +/- 0.16) and testicular size (21.1 +/- 0.17 cm). Both testicular and epididymal weight and dimensions were significantly affected (P < 0.05) by supplementation compared to controls. Testicular size was positively correlated to live BW (r = 0.53, P < 0.001). SC was positively correlated with ejaculate volume (r = 0.37, P < 0.001), sperm mass activity (r = 0.65, P < 0.001) and individual sperm progressive motility (r = 0.40; P < 0.001). Supplementation with Khat leftovers induced the highest improvement in live BW, testicular size, semen production and sperm motility in Ogaden bucks and can possibly be considered as a feed supplement to enhance goat production under smallholder livestock farming system in Ethiopia. PMID:17381680

Mekasha, Y; Tegegne, A; Rodriguez-Martinez, H

2007-04-01

87

Sperm competition in Odonata (Insecta): the evolution of female sperm storage and rivals' sperm displacement  

Microsoft Academic Search

Odonates (dragonflies) are well known for the ability of the males to displace sperm stored in the female's sperm- storage organs during copulation. By this means, copulating males are able to increase their fertilization success. This ability has been used as an example to illustrate a conflict of interests between the sexes in which males have evolved sperm-displacement mechanisms whilst

E. Uh ´ õa; A. Cordero River; E. U. E. T. Forestal

2003-01-01

88

Comparative responses of sperm cells and embryos of Pacific oyster (Crassostrea gigas) to exposure to metolachlor and its degradation products.  

PubMed

Metolachlor is one of the most intensively used chloroacetanilide herbicides in agriculture. Consequently, it has been frequently detected in coastal waters as well as its major degradation products, metolachlor ethane sulfonic acid (MESA) and metolachlor oxanilic acid (MOA) which are encountered at higher concentrations than metolachlor. Although a few studies of metolachlor toxicity have been conducted on marine organisms, little is known about the environmental toxicity of metolachlor degradation products. In this study, the deleterious effects of metolachlor and its degradation products on spermatozoa and embryos of Crassostrea gigas have been compared using biomarkers of developmental defects, DNA damage and gene transcription levels. After 24h exposure, significant increases in the percentage of abnormal D-larvae and DNA damage were observed from 0.01 ?g L(-1) for S-metolachlor and 0.1 ?g L(-1) for MESA and MOA. Results showed that S-metolachlor was more embryotoxic and genotoxic than its degradation products. Oyster sperm was also very sensitive to metolachlor exposure and followed the pattern: metolachlor (0.01 ?g L(-1))>MOA (0.1 ?g L(-1))>MESA (1 ?g L(-1)). Metolachlor and MESA mainly triggered variations in the transcription level of genes encoding proteins involved in oxidative stress responses (mitochondrial superoxide dismutase and catalase). Overall, no significant variation in transcription levels could be detected in C. gigas embryos exposed to MOA. This study demonstrates that metolachlor and its main degradation products have the potential to impact several steps of oyster development and therefore recruitment in coastal areas exposed to chronic inputs of pesticides. PMID:24378469

Mai, Huong; Gonzalez, Patrice; Pardon, Patrick; Tapie, Nathalie; Budzinski, Hélène; Cachot, Jérôme; Morin, Bénédicte

2014-02-01

89

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

PubMed Central

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. Images Fig. 2 Fig. 6

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

1993-01-01

90

Increase in concentration of soluble HLA-G in high-quality embryos after intracytoplasmic sperm injection  

PubMed Central

Non-invasive methods are normally preferred to conventional invasive methods when selecting suitable embryos to improve pregnancy rates after assisted reproduction techniques. One of the most recognized non-invasive methods is to examine the supernatants of embryo culture media. Soluble human leukocyte antigen, class I, G (sHLA-G) antigen is a non-classical class I molecule that has been widely considered as a marker of pregnancy failure or implantation success. In the current study of some Iranian patients, we examined the concentration of sHLA-G at different time points after intracytoplasmic sperm injection and compared the rates to the morphology and quality of the selected embryos. We showed that the concentration of sHLA-G increases over time in high-quality embryos. We conclude that there is a positive relationship between morphology, quality, and sHLA-G concentration. We suggest that this relationship can be used to increase the chance of a successful pregnancy.

Novin, Marefat Ghaffari; Ahmadi, Farzaneh; Khorshid, Mehran; Najafi, Tohid; Molouki, Aidin; Salehpour, Saghar; Bandehpour, Mojgan; Heidari, Matineh; Sato, Eimi

2011-01-01

91

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.

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

2013-01-01

92

Individual adjustment of sperm expenditure accords with sperm competition theory.  

PubMed

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. In contrast, according to the "intensity model" of sperm competition [Parker, G. A., Ball, M. A., Stockley, P. & Gage, M. J. G. (1996) Proc. R. Soc. London Ser. B 263, 1291-1297], when more than two ejaculates compete during a given mating event, sperm expenditure should decrease as the number of competing males increases. Empirical evidence supporting this prediction, however, is still lacking. Here we measured sperm expenditure in two gobiid fishes, the grass (Zosterisessor ophiocephalus) and black goby (Gobius niger), in which up to six sneakers can congregate around the nest of territorial males and release their sperm when females spawn. We show that, in accordance with theory, sneaker males of both species release fewer sperm as the number of competitors increases. PMID:12107282

Pilastro, Andrea; Scaggiante, Marta; Rasotto, Maria B

2002-07-23

93

In vitro production of cattlexbuffalo hybrid embryos using cattle oocytes and African buffalo (Syncerus caffer caffer) epididymal sperm.  

PubMed

Interspecies hybridization of bovids occurs between domestic cattle and at least three other species; American bison (Bison bison), yak (Bos grunniens) and banteng (Bos banteng). Birth of a cattlexbuffalo (Bubalus bubalis) hybrid has reportedly occurred in Russia and in China, but these reports were not authenticated. Such hybrids could be important in improving livestock production and management of diseases that impede production in tropical Africa. This study investigated hybridization between cattle and its closest African wild bovid relative, the African buffalo (Syncerus caffer caffer). In an attempt to produce cattlexbuffalo hybrid embryos in vitro, matured cattle oocytes were subjected to a standard in vitro fertilization (IVF) procedure with either homologous cattle (n=1166 oocytes) or heterologous African buffalo (n=1202 oocytes) frozen-thawed epididymal sperm. After IVF, 67.2% of the oocytes inseminated with the homologous cattle sperm cleaved. In contrast, fertilization with buffalo sperm resulted in only a 4.6% cleavage rate. The cleavage intervals were also slower in hybrid embryos than in the IVF-derived cattle embryos. Of the cleaved homologous cattle embryos 52.2% progressed to the morula stage compared with 12.7% for the buffalo hybrid embryos. No hybrid embryos developed beyond the early morula stage, while 40.1% of the cleaved cattlexcattle embryos developed to the blastocyst stage. Transfer of buffalo hybrid IVF embryos to domestic cattle surrogates resulted in no pregnancies at 60 days post-transfer. This study indicates that interspecies fertilization of cattle oocytes with African buffalo epididymal sperm can occur in vitro, and that a barrier to hybridization occurs in the early stages of embryonic development. Chromosomal disparity is likely the cause of the fertilization abnormalities, abnormal development and subsequent arrest impairing the formation of hybrid embryos beyond the early morula stage. Transfer of the buffalo hybrid embryos did not rescue the embryos from development arrest. PMID:19118889

Owiny, O D; Barry, D M; Agaba, M; Godke, R A

2009-04-01

94

Effects of immunization against alpha-inhibin using two adjuvants on daily sperm production and hormone concentrations in ram lambs.  

PubMed

Twenty-five ram lambs were immunized against alpha-inhibin peptide emulsified in Freund's adjuvant (FRA), Emulsigen (EML) containing an oligodeoxynucleotide as an immunostimulant, or adjuvant without alpha-inhibin antigen (control). Four immunizations were administered during an 85-d period, after which testes were obtained for determination of daily sperm production (DSP) and histological evaluation. alpha-Inhibin antibody (Ab) titers were 70-fold greater in lambs treated with FRA than in EML-treated ram lambs. alpha-Inhibin immunization had no effect on testes weight or on plasma concentrations of follicle-stimulating hormone (FSH), luteinizing hormone (LH), and testosterone. Mean DSP/g tended (P=0.1) to be greater in alpha-inhibin-immunized (EML=17.6x10(6); FRA=15.8x10(6)) ram lambs than in control animals (14.4x10(6)). One of the 8 control ram lambs had an elevated DSP/g, which was a statistical outlier. Without data from this lamb, DSP/g was increased (P<0.01) in alpha-inhibin-immunized ram lambs by 28% over controls. No association was found between the titer of alpha-inhibin Ab developed and DSP/g. Histologically, the percentage of testicular area occupied by seminiferous tubules differed (P=0.01) by treatment and was greatest (82%) in EML-treated ram alpha-inhibin-immunized lambs and lowest (74%) in control animals. Percentage tubular area and DSP/g were correlated (r=0.57, P=0.003). Findings show that (1) the extent of the increase in DSP/g is not dependent on the titer of alpha-inhibin Ab; (2) the increase in DSP/g is achieved through an increase in the mass of seminiferous tubules; and (3) FRA elicits a greater alpha-inhibin Ab titer than EML containing an oligodeoxynucleotide. PMID:19646838

Voge, J L; Parker, J B; Wheaton, J E

2009-11-01

95

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.

Ghaffari, Mohammad Ali; Rostami, Morad

2012-01-01

96

Daily sperm production and evaluation of morphological reproductive parameters of Murrah buffaloes in an extensive breeding system.  

PubMed

The development of male sexual maturity varies among buffaloes. The Murrah buffalo is considered the most important and efficient milk and fat producer, but aspects of its reproductive biology are still unknown. The present study aimed to evaluate the daily sperm production (DSP) and spermatogenesis in developing Murrah buffalo bulls by evaluation of the seminiferous tubules, testicular morphometry and using light microscopy and scanning electron microscopy. The testes of Murrah buffalo bulls at 18 mo was immature and at 24 mo could still be considered an average-efficiency breed based on their DSP. At 24 mo, the DSP rate was 0.97 billion sperm per testis and 13 million sperm per gram of testis. However, the animals had superior morphometric parameters compared with those of other livestock animals, except for the seminiferous tubule volume and diameter, which were inferior. In conclusion, our data support former views that the testes of the Murrah breed does not reach sexual maturity before 2 y of age and that important developmental steps occur later than Murrah crossbreeds from Brazil. PMID:22670218

da Luz, Patrícia A C; Andrighetto, Cristiana; Santos, Paulo R S; Jorge, André; Constantino, Maria Vitória P; Pereira, Flávia T V; Mess, Andrea; Neto, Antônio C Assis

2012-04-01

97

Off-axis effects on the multipulse structure of sperm whale usual clicks with implications for sound production  

NASA Astrophysics Data System (ADS)

Sperm whales (Physeter macrocephalus) produce multipulsed clicks with their hypertrophied nasal complex. The currently accepted view of the sound generation process is based on the click structure measured directly in front of, or behind, the whale where regular interpulse intervals (IPIs) are found between successive pulses in the click. Most sperm whales, however, are recorded with the whale in an unknown orientation with respect to the hydrophone where the multipulse structure and the IPI do not conform to a regular pulse pattern. By combining far-field recordings of usual clicks with acoustic and orientation information measured by a tag on the clicking whale, we analyzed clicks from known aspects to the whale. We show that a geometric model based on the bent horn theory for sound production can explain the varying off-axis multipulse structure. Some of the sound energy that is reflected off the frontal sac radiates directly into the water creating an intermediate pulse p1/2 seen in off-axis recordings. The powerful p1 sonar pulse exits the front of the junk as predicted by the bent-horn model, showing that the junk of the sperm whale nasal complex is both anatomically and functionally homologous to the melon of smaller toothed whales.

Zimmer, Walter M. X.; Madsen, Peter T.; Teloni, Valeria; Johnson, Mark P.; Tyack, Peter L.

2005-11-01

98

Testis stereology, seminiferous epithelium cycle length, and daily sperm production in the ocelot (Leopardus pardalis).  

PubMed

Similar to most wild felids, the ocelot (Leopardus pardalis) is an endangered species. However, knowledge regarding reproductive biology of the ocelot is very limited. Germ cell transplantation is an effective technique for investigating spermatogenesis and stem cell biology in mammals, and the morphologic characterization of germ cells and knowledge of cycle length are potential tools for tracking the development of transplanted germ cells. Our goal was to investigate basic aspects related to testis structure, particularly spermatogenesis, in the ocelot. Four adult males were used. After unilateral orchiectomy, testis samples were routinely prepared for histologic, stereologic, and autoradiographic analyses. Testis weight and the gonadosomatic index were 11+/-0.6g and 0.16+/-0.01%, respectively, whereas the volume density of seminiferous tubules and Leydig cells was 83.2+/-1.6% and 9.8+/-1.5%. Based on the acrosomic system, eight stages of spermatogenesis were characterized, and germ cell morphology was very similar to that of domestic cats. Each spermatogenic cycle lasted 12.5+/-0.4 d, and the entire spermatogenic process lasted 56.3+/-1.9 d. Individual Leydig cell volume was 2522mum(3), whereas the number of Leydig and Sertoli cells per gram of testis was 38+/-5x10(6) and 46+/-3x10(6). Approximately 4.5 spermatids were found per Sertoli cell, whereas daily sperm production per gram of testis was 18.3+/-1x10(6), slightly higher than values reported for other felids. The knowledge obtained in this study could be very useful to the preservation of the ocelot using domestic cat testes to generate and propagate the ocelot genome. PMID:19853903

Silva, R C; Costa, G M J; Andrade, L M; França, L R

2010-01-15

99

Social cues of sperm competition influence accessory reproductive gland size in a promiscuous mammal  

PubMed Central

Theory predicts that males should increase overall investment in ejaculate expenditure with increasing levels of sperm competition. Since ejaculate production is costly, we may expect males to tailor their reproductive investment according to anticipated levels of sperm competition. Here, we investigate plasticity in ejaculate investment in response to cues of population average levels of sperm competition in a promiscuous mammal, the bank vole (Myodes glareolus). We manipulated the social experience of experimental subjects during sexual development via differential exposure to the odour of rival males, to simulate conditions associated with relatively high or low average levels of sperm competition. Males exposed to a high level of competition developed larger major accessory reproductive glands (seminal vesicles) than those that experienced a low level of competition, suggesting that an increased investment in the production of copulatory plugs and/or mating rate may be beneficial at relatively high sperm competition levels. However, investment in sperm production, testis size and sperm motility were not altered according to social experience. Our findings emphasize the importance of non-sperm components of the ejaculate in mammalian postcopulatory sexual selection, and add to the growing evidence linking plasticity in reproductive traits to social cues of sperm competition.

Lemaitre, Jean-Francois; Ramm, Steven A.; Hurst, Jane L.; Stockley, Paula

2011-01-01

100

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

101

Production of fertile eggs and sperms in laboratory-reared amphioxus Branchiostoma belcheri tsingtaunese  

NASA Astrophysics Data System (ADS)

Althoug hamphioxus has been studied embryologically for over 130 years, little is known concerning the gonadal development of the laboratory-reared animal. The present study in which the amphioxus were sucessfully maintained in the laboratory for more than one year showed that they could produce fertile eggs and sperms like their wild counterparts.

Zhang, Shi-Cui; Zhu, Jin-Tian; Jia, Cui-Hong; Li, Guo-Rong

1999-03-01

102

Paradoxical effect of reagents for sulfhydryl and disulfide groups on human sperm capacitation and superoxide production  

Microsoft Academic Search

Spermatozoa must undergo capacitation prior to fertilization. In humans, this process appears regulated by oxidoreduction reactions. We investigated the possibility that these reactions involved the sulfhydryl-disulfide pair, which offers a reversible regulation of cellular processes. The effects of reagents targeted for sulfhydryl and disulfide groups on human sperm capacitation, superoxide (O2•?) generation and protein tyrosine phosphorylation were evaluated. The sulfhydryl

Eve de Lamirande; Claude Gagnon

1998-01-01

103

Sperm preparation for ART  

PubMed Central

The onset of clinical assisted reproduction, a quarter of a century ago, required the isolation of motile spermatozoa. As the indication of assisted reproduction shifted from mere gynaecological indications to andrological indications during the years, this urged andrological research to understand the physiology of male germ cell better and develop more sophisticated techniques to separate functional spermatozoa from those that are immotile, have poor morphology or are not capable to fertilize oocytes. Initially, starting from simple washing of spermatozoa, separation techniques, based on different principles like migration, filtration or density gradient centrifugation evolved. The most simple and cheapest is the conventional swim-up procedure. A more sophisticated and most gentle migration method is migration-sedimentation. However, its yield is relatively small and the technique is therefore normally only limited to ejaculates with a high number of motile spermatozoa. Recently, however, the method was also successfully used to isolate spermatozoa for intracytoplasmic sperm injection (ICSI). Sperm separation methods that yield a higher number of motile spermatozoa are glass wool filtration or density gradient centrifugation with different media. Since Percoll® as a density medium was removed from the market in 1996 for clinical use in the human because of its risk of contamination with endotoxins, other media like IxaPrep®, Nycodenz, SilSelect®, PureSperm® or Isolate® were developed in order to replace Percoll®. Today, an array of different methods is available and the selection depends on the quality of the ejaculates, which also includes production of reactive oxygen species (ROS) by spermatozoa and leukocytes. Ejaculates with ROS production should not be separated by means of conventional swim-up, as this can severely damage the spermatozoa. In order to protect the male germ cells from the influence of ROS and to stimulate their motility to increase the yield, a number of substances can be added to the ejaculate or the separation medium. Caffeine, pentoxifylline and 2-deoxyadenosine are substances that were used to stimulate motility. Recent approaches to stimulate spermatozoa include bicarbonate, metal chelators or platelet-activating factor (PAF). While the use of PAF already resulted in pregnancies in intrauterine insemination, the suitability of the other substances for the clinical use still needs to be tested. Finally, the isolation of functional spermatozoa from highly viscous ejaculates is a special challenge and can be performed enzymatically to liquefy the ejaculate. The older method, by which the ejaculate is forcefully aspirated through a narrow-gauge needle, should be abandoned as it can severely damage spermatozoa, thus resulting in immotile sperm.

Henkel, Ralf R; Schill, Wolf-Bernhard

2003-01-01

104

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

105

The effects of four insect growth-regulating (IGR) insecticides on honeybee (Apis mellifera L.) colony development, queen rearing and drone sperm production.  

PubMed

This study assessed the effects of exposure to IGRs on the long-term development of the honeybee colony, viability of queens and sperm production in drones and integrated the data into a honeybee population model. Colonies treated with diflubenzuron resulted in a short-term reduction in the numbers of adult bees and brood. Colonies treated with fenoxycarb declined during the season earlier and started the season slower. The number of queens that successfully mated and laid eggs was affected in the fenoxycarb treatment group but there were no significant differences in the drone sperm counts between the colonies. An existing honeybee population model was modified to include exposure to IGRs. In the model, fenoxycarb reduced the winter size of the colony, with the greatest effects following a June or an August application. Assuming a 'larvae per nurse bee' ratio of 1.5 for brood rearing capability, the reduction in winter size of a colony following a fenoxycarb application was at its worst about 8%. However, even if only those bees reared within 2 weeks of the IGR being applied are subject to premature ageing, this might significantly reduce the size of over-wintering colonies, and increase the chance of the bee population dwindling and dying in late winter or early spring. PMID:16160749

Thompson, Helen M; Wilkins, Selwyn; Battersby, Alastair H; Waite, Ruth J; Wilkinson, David

2005-10-01

106

Gestational and lactational exposure of rats to xenoestrogens results in reduced testicular size and sperm production.  

PubMed Central

This study assessed whether exposure of male rats to two estrogenic, environmental chemicals, 4-octylphenol (OP) and butyl benzyl phthalate (BBP) during gestation or during the first 21 days of postnatal life, affected testicular size or spermatogenesis in adulthood (90-95 days of age). Chemicals were administered via the drinking water or concentrations of 10-1000 micrograms/l (OP) or 1000 micrograms/l (BBP), diethylstilbestrol (DES; 100 micrograms/l) and an octylphenol polyethoxylate (OPP; 1000 micrograms/l), which is a weak estrogen or nonestrogenic in vitro, were administered as presumptive positive and negative controls, respectively. Controls received the vehicle (ethanol) in tap water. In study 1, rats were treated from days 1-22 after births in studies 2 and 3, the mothers were treated for approximately 8-9 weeks, spanning a 2-week period before mating throughout gestation and 22 days after giving birth. With the exception of DES, treatment generally had no major adverse effect or body weight: in most instances, treated animals were heavier than controls at day 22 and at days 90-95. Exposure to OP, OPP, or BBP at a concentration of 1000 micrograms/1 resulted in a small (5-13%) but significant (p < 0.01 or p < 0.0001) reduction in mean testicular size in studies 2 and 3, an effect that was still evident when testicular weight was expressed relative to body, weight or kidney weight. The effect of OPP is attributed to its metabolism in vivo to OP. DES exposure caused similar reductions in testicular size but also caused reductions in body weight, kidney weight, and litter size. Ventral prostate weight was reduced significantly in DES-treated rats and to minor extent in OP-treated rats. Comparable but more minor effects of treatment with DES or OP on testicular size were observed in study 1. None of the treatments had any adverse effect on testicular morphology or on the cross-sectional area of the lumen or seminiferous epithelium at stages VII-VIII of the spermatogenic cycle, but DES, OP, and BBP caused reductions of 10-21% (p < 0.05 to p < 0.001) in daily sperm production. Humans are exposed to phthalates, such as BBP, and to alkylphenol polyethoxylates, such as OP, but to what extent is unknown. More detailed studies are warranted to assess the possible risk to the development of the human testis from exposure to these and other environmental estrogens. Images Figure 1. Figure 2. Figure 3. A Figure 3. B Figure 3. C Figure 3. D Figure 4.

Sharpe, R M; Fisher, J S; Millar, M M; Jobling, S; Sumpter, J P

1995-01-01

107

Effects of immunization against two inhibin antigens on daily sperm production and hormone concentrations in ram lambs.  

PubMed

The gonadal hormone inhibin regulates daily sperm production (DSP) indirectly through negative feedback control of FSH secretion and may also affect DSP via direct actions within the testis. Studies attempting to increase DSP through the immunization against inhibin have yielded equivocal results. The current study compared 2 inhibin antigens for effects on DSP and hormone secretion. Hampshire ram lambs (BW = 42 +/- 2 kg; age = 113 +/- 3 d) were assigned randomly to 3 groups: 1) control (n = 4); 2) alpha-peptide conjugate (PTC, n = 6); and 3) alpha-subunit (SUB, n = 6). Antigen PTC consisted of an alpha-inhibin, N-terminal, 25-amino acid peptide conjugated to ovalbumin. Antigen SUB was the complete inhibin alpha-subunit. Lambs were immunized on d 0 (June 19, 2006), 18, 38, and 63. Body weight was recorded on immunization days and scrotal circumference on d 63. Blood samples were collected on d 0, 7, 14, 18, 28, 35, 38, 49, 56, 63, and 70. Rams were slaughtered on d 71. Testes were weighed, and parenchyma was obtained for DSP determination. Plasma alpha-inhibin antibody titer and LH, FSH, and testosterone concentrations were measured. alpha-Inhibin antibody titer was first detectable on d 14 in both PTC- and SUB-immunized ram lambs and generally increased thereafter. Mean DSP per gram of testis (DSP/g) was increased (P < 0.01) 26% in PTC- and SUB-immunized ram lambs over that in control ram lambs. Total DSP per ram lamb and testes weight did not differ among the 3 treatment groups. Variation in DSP per ram lamb and testes weight were greater (P = 0.05) in PTC- and SUB-immunized ram lambs than in control ram lambs. Plasma FSH concentrations were similar in PTC- and SUB-immunized ram lambs. Immunization against either alpha-inhibin antigen did not alter LH, testosterone, BW, or scrotal circumference. Findings indicate that 1) the 2 alpha-inhibin antigens increase DSP/g to similar extents; 2) alpha-inhibin antibody may act at least in part through an intratesticular mechanism because DSP/g was increased in some animals without concomitant increases in FSH; and 3) immunization against alpha-inhibin may affect testes weight by actions independent of those that regulate DSP/g. PMID:17878277

Voge, J L; Wheaton, J E

2007-12-01

108

Quality assessment of bovine cryopreserved sperm after sexing by flow cytometry and their use in in vitro embryo production  

Microsoft Academic Search

The objective was to evaluate the structural and functional quality of bull sperm after sexing by flow cytometry. Frozen non-sexed (NS), sexed for X (SX) and sexed for Y (SY) sperm from four bulls was used. Frozen-thawed sperm was analyzed for motility, sperm head agglutination, morphology, capacitation, and integrity of the plasma membrane, acrosome, and chromatin. After Percoll centrifugation (45:60%

J. O. Carvalho; R. Sartori; G. M. Machado; G. B. Mourão; M. A. N. Dode

2010-01-01

109

Fracturing high-permeability reservoirs increases productivity  

SciTech Connect

Hydraulic fracturing of high-permeability reservoirs has increased long-term hydrocarbon production and reduced sand production in many areas of the world. A key element is the reduction of near well bore drawdown during production. Drawdown, the difference between reservoir and production pressures, is the driving force for flow into the well bore. As drawdown increases because of higher production rates or depletion, formation instability may cause fines and sand to migrate into the well bore region. A greater well bore radius reduces both radial velocity and drawdown. Fracturing beyond the well bore region effectively bypasses the damaged zone, increasing the effective radius of the well bore and enabling higher flow rates with lower drawdown pressures. In essence, the reservoir energy is used more efficiently because the conductive proppant bed bypasses the near well bore restrictions. The paper discusses candidate well selection; proppant selection; sand control; minifrac procedures; spurt losses; fracture design; equipment; case histories in West Africa and offshore Louisiana.

Dusterhoft, R.G. (Halliburton Energy Services, Duncan, OK (United States)); Chapman, B.J. (Halliburton Energy Services, New Orleans, LA (United States))

1994-06-20

110

Selenium increases seed production in Brassica  

Microsoft Academic Search

Selenium (Se) is essential for humans and animals but is not considered to be essential for higher plants. Although researchers\\u000a have found increases in vegetative growth due to fertiliser Se, there has been no definitive evidence to date of increased\\u000a reproductive capacity, in terms of seed production and seed viability. The aim of this study was to evaluate seed production

G. H. Lyons; Y. Genc; K. Soole; J. C. R. Stangoulis; F. Liu; R. D. Graham

2009-01-01

111

Sperm competition games: optimal sperm allocation in response to the size of competing ejaculates  

PubMed Central

Sperm competition theory predicts that when males are certain of sperm competition, they should decrease sperm investment in matings with an increasing number of competing ejaculates. How males should allocate sperm when competing with differently sized ejaculates, however, has not yet been examined. Here, we report the outcomes of two models assuming variation in males' sperm reserves and males being faced with different amounts of competing sperm. In the first ‘spawning model’, two males compete instantaneously and both are able to assess the sperm competitive ability of each other. In the second ‘sperm storage model’, males are sequentially confronted with situations involving different levels of sperm competition, for instance different amounts of sperm already stored by the female mating partner. In both of the models, we found that optimal sperm allocation will strongly depend on the size of the male's sperm reserve. Males should always invest maximally in competition with other males that are equally strong competitors. That is, for males with small sperm reserves, our model predicts a negative correlation between sperm allocation and sperm competition intensity, whereas for males with large sperm reserves, this correlation is predicted to be positive.

Engqvist, Leif; Reinhold, Klaus

2006-01-01

112

Treating ram sperm with cholesterol-loaded cyclodextrins improves cryosurvival.  

PubMed

Acceptable fertility using cryopreserved ram sperm is currently only achieved using laparoscopic intrauterine insemination. Improving the cryosurvival of ram sperm may permit greater fertility rates using more practical techniques. This study was conducted to determine if treating ram sperm with six different cyclodextrins pre-loaded with cholesterol (CLC), prior to cryopreservation increases sperm cryosurvival and if this technology can be used with neat semen. Subsequent experiments evaluated how adding CLC to sperm affected sperm cholesterol content, sperm osmotic tolerance limits, sperm post-thaw survival after incubation and the capacity of sperm to bind to zona pellucidae of cattle and sheep oocytes. Sperm treated with 2-hydroxypropyl-beta-cyclodextrin prior to cryopreservation exhibited greater percentages of motile sperm (62%) compared to the control (no CLC treatment) samples (43%, P<0.05), after thawing. In addition, samples treated with methyl-beta-cyclodextrin exhibited percentages of motile and viable sperm similar to samples treated with 2-hydroxypropyl-beta-cyclodextrin. Other CLC-treated samples were similar to the control. The CLC concentration that optimized sperm cryosurvival was 2mg CLC/120 x 10(6) sperm for both methyl-beta- and 2-hydroxypropyl-beta-cyclodextrin when added to neat semen prior to cryopreservation. Addition of 2mg CLC not only maintained greater percentages of motile sperm compared to the control samples, but maintained greater percentages of motile sperm during a 3h incubation after thawing. In addition, 2-hydroxypropyl-beta-cyclodextrin pre-loaded with cholesterol maintained greater percentages of viable sperm (33%), than control sperm (18%; P<0.05). Treating ram sperm with CLC increased the sperm cholesterol content>1.9-fold and although some cholesterol was lost from the sperm during cooling and cryopreservation, the cholesterol content remained greater in CLC-treated sperm after cooling and after thawing than in control sperm (P<0.05). In addition, CLC-treated sperm maintained greater percentages of motile sperm through a wide range of osmotic solutions (150 and 425 mOsm) while control sperm lost motility in solutions outside a more narrow range (270 to 370 mOsm). Greater numbers of CLC-treated sperm bound to zona pellucida than control sperm (P<0.05), although number of sperm binding cattle and sheep oocytes, was similar (P>0.05). In conclusion, treating ram sperm with CLC increases sperm cryosurvival rates and sperm longevity after thawing. It also increases the cholesterol content, osmotic tolerance, and zona-binding capabilities of sperm. Finally, CLCs can be added to neat semen, making this technology feasible for practical application using current cryopreservation techniques for ram semen. PMID:19615833

Mocé, Eva; Purdy, Phillip H; Graham, James K

2010-04-01

113

Adiponectin Lowers Glucose Production by Increasing SOGA  

PubMed Central

Adiponectin is a hormone that lowers glucose production by increasing liver insulin sensitivity. Insulin blocks the generation of biochemical intermediates for glucose production by inhibiting autophagy. However, autophagy is stimulated by an essential mediator of adiponectin action, AMPK. This deadlock led to our hypothesis that adiponectin inhibits autophagy through a novel mediator. Mass spectrometry revealed a novel protein that we call suppressor of glucose by autophagy (SOGA) in adiponectin-treated hepatoma cells. Adiponectin increased SOGA in hepatocytes, and siRNA knockdown of SOGA blocked adiponectin inhibition of glucose production. Furthermore, knockdown of SOGA increased late autophagosome and lysosome staining and the secretion of valine, an amino acid that cannot be synthesized or metabolized by liver cells, suggesting that SOGA inhibits autophagy. SOGA decreased in response to AICAR, an activator of AMPK, and LY294002, an inhibitor of the insulin signaling intermediate, PI3K. AICAR reduction of SOGA was blocked by adiponectin; however, adiponectin did not increase SOGA during PI3K inhibition, suggesting that adiponectin increases SOGA through the insulin signaling pathway. SOGA contains an internal signal peptide that enables the secretion of a circulating fragment of SOGA, providing a surrogate marker for intracellular SOGA levels. Circulating SOGA increased in parallel with adiponectin and insulin activity in both humans and mice. These results suggest that adiponectin-mediated increases in SOGA contribute to the inhibition of glucose production.

Cowerd, Rachael B.; Asmar, Melissa M.; Alderman, J. McKee; Alderman, Elizabeth A.; Garland, Alaina L.; Busby, Walker H.; Bodnar, Wanda M.; Rusyn, Ivan; Medoff, Benjamin D.; Tisch, Roland; Mayer-Davis, Elizabeth; Swenberg, James A.; Zeisel, Steven H.; Combs, Terry P.

2010-01-01

114

Binding pattern and toxicological effects of lectins from genus Canavalia on bovine sperm.  

PubMed

The aim of this study was to determine the binding patterns of Canavalia ensiformis (ConA), Canavalia boliviana (ConBol) and Canavalia brasiliensis (ConBr) lectins to bovine sperm and their effects on sperm motility, viability, lipid peroxidation, reactive oxygen species production and fertilization ability. ConA bound to whole spermatozoa, with the exception of the equatorial segment, ConBol did not interact with the acrosome region and ConBr exhibited a fragmented binding pattern. The three lectins decreased sperm motility but did not affect cell viability or lipid peroxidation. Nevertheless, ROS production was increased in comparison to controls and a reduction in the cleavage and blastocyst ratio was induced in comparison to controls. In conclusion, this study determined that structurally similar lectins interact differently with bovine sperm and affect sperm motility, viability, lipid peroxidation, ROS production and fertilization ability in various ways. PMID:23524305

Kaefer, Cristian; Komninou, Eliza R; Campos, Vinicius F; de Leon, Priscila M; Arruda, Francisco Vassiliepe S; Nascimento, Kyria S; Teixeira, Edson H; Stefanello, Francielli M; Barschak, Alethéa G; Deschamps, João Carlos; Seixas, Fabiana K; Cavada, Benildo S; Collares, Tiago

2013-07-01

115

Effect of astaxanthin on human sperm capacitation.  

PubMed

In order to be able to fertilize oocytes, human sperm must undergo a series of morphological and structural alterations, known as capacitation. It has been shown that the production of endogenous sperm reactive oxygen species (ROS) plays a key role in causing cells to undergo a massive acrosome reaction (AR). Astaxanthin (Asta), a photo-protective red pigment belonging to the carotenoid family, is recognized as having anti-oxidant, anti-cancer, anti-diabetic and anti-inflammatory properties and is present in many dietary supplements. This study evaluates the effect of Asta in a capacitating buffer which induces low ROS production and low percentages of acrosome-reacted cells (ARC). Sperm cells were incubated in the presence or absence of increasing concentrations of Asta or diamide (Diam) and analyzed for their ROS production, Tyr-phosphorylation (Tyr-P) pattern and percentages of ARC and non-viable cells (NVC). Results show that Asta ameliorated both sperm head Tyr-P and ARC values without affecting the ROS generation curve, whereas Diam succeeded in enhancing the Tyr-P level but only of the flagellum without increasing ARC values. It is suggested that Asta can be inserted in the membrane and therefore create capacitation-like membrane alteration which allow Tyr-P of the head. Once this has occurred, AR can take place and involves a higher numbers of cells. PMID:23736766

Donà, Gabriella; Kožuh, Ivana; Brunati, Anna Maria; Andrisani, Alessandra; Ambrosini, Guido; Bonanni, Guglielmo; Ragazzi, Eugenio; Armanini, Decio; Clari, Giulio; Bordin, Luciana

2013-06-01

116

Automated sperm immobilization for intracytoplasmic sperm injection.  

PubMed

Sperm immobilization is a requisite step in intracytoplasmic sperm injection (ICSI). Conventionally, sperm immobilization is performed manually, which entails long training hours and stringent skills. Manual sperm immobilization also has the limitation of low success rates and poor reproducibility due to human fatigue and skill variations across operators. This paper presents a system for fully automated sperm immobilization to eliminate limitations in manual operation. Integrating computer vision and motion control algorithms, the automated system is able to visually track a sperm and control a micropipette to immobilize the sperm. A robust sperm tail tracking algorithm is developed to locate the optimal position on the sperm tail for sperm immobilization. The system demonstrates: 1) an average sperm tail tracking error of 0.95 ?m; 2) a sperm tail visual tracking success rate of 96%; 3) a sperm immobilization success rate of 88.2% (based on 1000 trials); and 4) a speed of 6-7 s per successful immobilization. PMID:21156388

Leung, Clement; Lu, Zhe; Esfandiari, Navid; Casper, Robert F; Sun, Yu

2011-04-01

117

High pressure flow cytometric sorting damages sperm.  

PubMed

Sexing sperm by high-speed flow cytometry subjects them to high pressure. The routine operating pressure of the MoFlo SX flow cytometer for sperm sorting for commercial production has been 50 pounds/square inch (psi), with a standard 70 microm standard nozzle tip. It was hypothesized that lowering the sorting pressure could reduce sperm damage. Therefore, a series of experiments using semen from six bulls, sorted with three MoFlo SX sorters, was conducted to determine optimal pressure. An additional experiment was done with stallion spermatozoa. In Experiment 1, sorting at 30 psi compared to 50 psi with the 70 microm nozzle tip increased sperm motility post-thaw at 30 min and 2h from 40.5 to 48.0% and 30.0 to 40.2%, respectively (P<0.05). In Experiment 2, 49, 43, 37, 31, and 25 psi resulted in 24.2, 32.8, 35.6, 37.5, and 39.8% progressively motile spermatozoa post-thaw (P<0.05). In Experiment 3, 3 pressures (50, 40, 30 psi)x2 sorting methods were further evaluated. At 50, 40, and 30 psi, respective mean sperm motilities at 30 min were 44.8, 48.6, and 49.6% (P<0.05), and percentage of live spermatozoa were 51.7, 55.7, and 57.8% (P<0.05). The improvement of post-sort sperm quality with lowered pressure was also evident in stallion spermatozoa. After sorting at 30, 40 and 50 psi were 40.6, 34.5 and 30.1% motile spermatozoa (P<0.1), and were 76.7, 72.5 and 67.8% (P<0.05) live spermatozoa (determined by SYBR-14/propidium iodide staining). In Experiment 4 sorter performance was evaluated with two pressures (40 and 50 psi)x2 staining concentrations of bovine spermatozoa (75 x 10(6) and 100 x 10(6)mL(-1)). Lowering pressure to 40 psi did not lower sort rate and purity when compared to 50 psi (P>0.05), and higher sperm concentration during staining increased sort rate (P<0.05). In conclusion, lowering pressure of the MoFlo SX flow cytometer for sperm sorting from 50 psi (standard pressure) to 40 psi clearly improved sperm quality without a significant decrease in sorter performance. PMID:16125550

Suh, T K; Schenk, J L; Seidel, G E

2005-09-15

118

Increasing productivity through Total Reuse Management (TRM)  

NASA Technical Reports Server (NTRS)

Total Reuse Management (TRM) is a new concept currently being promoted by the NASA Langley Software Engineering and Ada Lab (SEAL). It uses concepts similar to those promoted in Total Quality Management (TQM). Both technical and management personnel are continually encouraged to think in terms of reuse. Reuse is not something that is aimed for after a product is completed, but rather it is built into the product from inception through development. Lowering software development costs, reducing risk, and increasing code reliability are the more prominent goals of TRM. Procedures and methods used to adopt and apply TRM are described. Reuse is frequently thought of as only being applicable to code. However, reuse can apply to all products and all phases of the software life cycle. These products include management and quality assurance plans, designs, and testing procedures. Specific examples of successfully reused products are given and future goals are discussed.

Schuler, M. P.

1991-01-01

119

Exploring Increased Productivity Through Employee Engagement  

NASA Astrophysics Data System (ADS)

Disengaged employees cost U.S. companies billions of dollars annually in lowered productivity, a cost which has been compounded by the difficult economic situations in the country. The potential for increasing productivity through increased employee engagement was examined in this study. Using personal engagement theory and the theory of planned behavior, the purpose of this phenomenological study was to explore how the experiences of salaried aerospace employees affected productivity and the financial performance of an organization. Interviews were conducted with a purposive sample of 20 aerospace employees whose responses were codified and analyzed to identify themes. The analysis indicated that (a) the lived experiences of employees influenced employee engagement, (b) employee engagement affects organizational commitment and performance, and (c) trust and respect and leadership are essential components to keep employees engaged. Eighty percent of the participants indicated that as employee engagement increases so too does organizational performance. The implications for positive social change include new insights for leaders seeking to increase productivity and financial performance, and to support employee engagement for maintaining sustainability, retaining talent, increasing profits, and improving the economy.

Richards, Wayne K., Jr.

120

Increased Fertilization Rates after In Vitro Culture of Frozen-Thawed Testicular Immotile Sperm in Nonobstructive Azoospermic Patients  

PubMed Central

Objective. To optimise the use of freeze/thaw testicular immotile spermatozoa from nonobstructive azoospermia patients and to analyse the outcome of intracytoplasmic sperm injection (ICSI) of such spermatozoa. Methods. Testicular specimens were retrieved and cryopreserved from forty patients with nonobstructive azoospermia and underwent one cycle with thawed spermatozoa (Group I) that led to pregnancy in sixteen cases. Twenty-four patients of group I underwent treatment with the same batch of thawed spermatozoa (Group II). For the first ICSI attempt, injection was performed when motile spermatozoa were found. In group II, injection was performed when maximum motility was reached. We compared mean of fertilization rate, embryo quality, clinical pregnancy rate and embryo implantation rate. Results. The mean percentage of motility was significantly higher in the group II than in the group I (18, 6 versus 8, 2). Group I showed a significant decrease in fertilization rates when compared with cryopreserved testicular spermatozoa in group II (54% versus 72%, P < 0.05). No difference was noted between the cleavage rate, embryo quality, clinical pregnancy rates and implantation rates among group II and I. Conclusion. Fecundation rate can be significantly improved after in-vitro culture and sperm selection of frozen-thawed immotile testicular spermatozoa in patients with nonobstructive azoospermia.

Nunez-Calonge, R.; Cortes, S.; Gago, M.; Lopez, P.; Caballero-Peregrin, P.

2012-01-01

121

Bactericidal/permeability-increasing protein in the reproductive system of male mice may be involved in the sperm-oocyte fusion.  

PubMed

Bactericidal/permeability-increasing protein (BPI) is a 455-residue (?55?kDa) protein found mainly in the primary (azurophilic) granules of human neutrophils. BPI is an endogenous antibiotic protein that belongs to the family of mammalian lipopolysaccharide (LPS)-binding and lipid transport proteins. Its major function is to kill Gram-negative bacteria, thereby protecting the host from infection. In addition, BPI can inhibit angiogenesis, suppress LPS-mediated platelet activation, increase DNA synthesis, and activate ERK/Akt signaling. In this study, we found that Bpi was expressed in the testis and epididymis but not in the seminal vesicles, prostate, and solidification glands. BPI expression in the epididymis increased upon upregulation of testosterone, caused by injection of GNRH. In orchidectomized mice, BPI expression was significantly reduced, but its expression was restored to 30% of control levels in orchidectomized mice that received supplementary testosterone. The number of sperm fused per egg significantly decreased after incubation with anti-BPI antiserum. These results suggest that BPI may take part in the process of sperm-oocyte fusion and play a unique and significant role in reproduction. PMID:23740083

Li, Kun; Liu, Yue; Xia, Xiaoyu; Wang, Li; Lu, Meige; Hu, Yanqin; Xu, Chen

2013-08-01

122

Increasing crop production through more controlled photosynthesis  

Microsoft Academic Search

Some of the information about photosynthesis and related biosynthesis that might be used to develop strategies for increasing crop yields are discussed. It seems possible that techniques of plant breeding can be used to exploit or improve some of the biochemical characteristics now understood for green plants. There may be specifically designed chemicals--for example, glycidate--that can alter production. Finally, we

J. A. Bassham

1977-01-01

123

Increasing Productivity: A Memo from the Chancellor  

ERIC Educational Resources Information Center

This memo proposes a 5 percent increase in productivity in the Dallas Community College District and invites all district personnel to participate by thinking of ways of achieving this goal without lowering standards of educational quality and without reducing salaries and wages. (DC)

Priest, Bill J.

1975-01-01

124

Offsetting Effects of Wolbachia Infection and Heat Shock on Sperm Production in Drosophila simulans: Analyses of Fecundity, Fertility and Accessory Gland Proteins  

Microsoft Academic Search

Infection in Drosophila simulans with the endocellular symbiont Wolbachia pipientis results in egg lethality caused by failure to properly initiate diploid development (cytoplasmic incompatibility, CI). The relation- ship between Wolbachia infection and reproductive factors influencing male fitness has not been well examined. Here we compare infected and uninfected strains of D. simulans for (1) sperm production, (2) male fertility, and

Rhonda R. Snook; Sophia Y. Cleland; Mariana F. Wolfner; Timothy L. Karr

125

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.

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

2012-01-01

126

Exposure to sperm competition risk improves survival of virgin males  

PubMed Central

Sperm competition between the ejaculates of multiple males for the fertilization of a given set of ova is taxonomically widespread. Males have evolved remarkable adaptations to increase their reproductive success under postcopulatory sexual selection, which in many species includes the ability to modify behaviour and ejaculate characteristics plastically to match the perceived level of sperm competition. Males of the model species Drosophila melanogaster increase mating duration and modify seminal fluid composition in response to short-term changes in sperm competition risk. If these responses increase a male's total investment in reproduction, he must either trade-off this cost against other life-history traits or suffer reduced survival. We tested whether mounting a plastic sperm competition response bears an instantaneous survival cost, and instead found that male D. melanogaster exposed to a high risk of sperm competition survive 12 per cent longer than those at low risk, equating to a 49 per cent reduction in the hourly hazard of death. This striking effect was found only among virgins: the high cost of mating in this species eliminates any such benefit among non-virgin males. Our results suggest that the improvement in survival found among virgins may be a product of males’ tactical responses to sperm competition.

Moatt, Joshua P.; Dytham, Calvin; Thom, Michael D. F.

2013-01-01

127

Artificial selection and heritability of sperm length in Gryllus bimaculatus  

Microsoft Academic Search

The adaptive significance of variation in sperm size remains poorly understood but there has been even less attention focused on the genetic mechanisms controlling spermatozoal traits (only three species have been studied). Here we explore heritability and artificial selection of sperm length in the cricket Gryllus bimaculatus. Using a within-family selection design we selected sperm with increasing and decreasing sperm

EDWARD H. MORROW; MATTHEW J. G. GAGE

2001-01-01

128

Production of androgenetic diploid loach by cold-shock of eggs fertilized with diploid sperm.  

PubMed

Diploid androgenotes were produced without egg irradiation in the loach, Misgurnus anguillicaudatus. Eggs of wild-type diploid females were fertilized with diploid sperm of a neo-tetraploid male and then cold-shock treated at 3 °C (range, ±0.5 °C) for 30 minutes just after fertilization to eliminate the female nucleus. After hatching, ploidy status of the hatched larvae was analyzed by flow cytometry, which revealed putative diploid androgenotes as well as larvae possessing other ploidies. Five independent microsatellite DNA markers were genotyped to confirm all-male inheritance of the resultant diploid larvae. The mean ± SD yield rate of diploid androgenetic larvae to total eggs used was 12.29 ± 3.25% in the cold-shock group and 22.23 ± 13.42% in the UV-irradiated group (P > 0.05). No diploid androgenetic larvae were detected in the intact control group. To our knowledge, this is the first report demonstrating successful induction of diploid androgenotes without egg irradiation in fish. PMID:23602217

Hou, Jilun; Fujimoto, Takafumi; Yamaha, Etsuro; Arai, Katsutoshi

2013-07-15

129

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.

M?ller, Anders Pape; Bonisoli-Alquati, Andrea; Mousseau, Timothy A.; Rudolfsen, Geir

2014-01-01

130

cDNA cloning and characterization of a human sperm antigen (SPAG6) with homology to the product of the Chlamydomonas PF16 locus.  

PubMed

Serum from an infertile male with high-titer anti-sperm antibodies was used to identify a novel human sperm antigen by screening of a testis expression library. The clone, initially designated Repro-SA-1 (HUGO-approved symbol SPAG6), was found to encode a sequence highly enriched in testis. The deduced amino acid sequence of the full-length cDNA revealed striking homology to the product of the Chlamydomonas reinhardtii PF16 locus, which encodes a protein localized to the central pair of the flagellar axoneme. The human gene encodes 1.8- and 2.8-kb mRNAs highly expressed in testis but not in prostate, ovary, spleen, thymus, small intestine, colon, peripheral blood leukocytes, heart, brain, placenta, liver, muscle, kidney, and pancreas. The gene was mapped to chromosome 10p11.2-p12. Antibodies raised against SPAG6 sequences localized the protein to the tails of permeabilized human sperm. Both the Chlamydomonas protein and SPAG6 contain eight contiguous armadillo repeats, which place them in a family of proteins known to mediate protein-protein interactions. The cloning of the human homologue of the Chlamydomonas PF16 locus provides a new avenue to explore the role of the axoneme central pair in human sperm function. PMID:10493827

Neilson, L I; Schneider, P A; Van Deerlin, P G; Kiriakidou, M; Driscoll, D A; Pellegrini, M C; Millinder, S; Yamamoto, K K; French, C K; Strauss, J F

1999-09-15

131

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

132

Treating boar sperm with cholesterol-loaded cyclodextrins widens the sperm osmotic tolerance limits and enhances the in vitro sperm fertilising ability.  

PubMed

Treating sperm with cholesterol-loaded cyclodextrins (CLC) improves the cryosurvival of the sperm of different cold-shock sensitive species. However, the response of boar sperm to this treatment is not fully understood. The aim of this study was to determine how CLC and methyl-?-cyclodextrin (M?CD, not loaded with cholesterol) affect the parameters for boar sperm functionality, including sperm osmotic resistance, and the ability of the sperm to capacitate and to penetrate the sow's immature oocytes in vitro. Samples treated with CLC or M?CD prior to freezing exhibited similar percentages of motile sperm, live sperm and sperm with intact acrosomes as the control samples (P>0.05). In addition, these treatments did not alter the response of the boar sperm to capacitating conditions. However, when compared to the controls and the M?CD-treated samples, the CLC-treated sperm maintained greater percentages of motile sperm and live sperm in a wide range of osmotic solutions including hypo- (50, 75 and 150 mOsm/kg) and hyper-osmotic (600, 800 mOsm/kg) conditions (P<0.05). In addition, the CLC-treated sperm exhibited greater oocyte penetration ability than the control and the M?CD-treated sperm (P<0.0001). In conclusion, the pre-freezing treatment of boar sperm with CLC does not alter the ability of the sperm to respond to capacitating conditions. Despite not increasing the cryosurvival of the sperm, this treatment widens the sperm osmotic tolerance limits and enhances the in vitro sperm fertilising ability. PMID:22218105

Tomás, Cristina; Blanch, Eva; Hernández, Marta; Gil, María A; Roca, Jordi; Vázquez, Juan M; Martínez, Emilio A; Mocé, Eva

2011-12-01

133

Increased frequencies of diploid sperm detected by multicolour FISH after treatment of rats with carbendazim without micronucleus induction in peripheral blood erythrocytes  

Microsoft Academic Search

The purpose of the present study was to determine the effect of a single oral dose of carbendazim (CARB) on the frequencies of numerical chromosome aberrations in sperm and on micronuclei in peripheral blood erythrocytes of rats. Dual colour FISH on epididymal sperm of rats treated 31 days before sacrifice (0, 50, 150, 450 and 800 mg\\/kg body wt CARB

Joyce M. de Stoppelaar; Ton van de Kuil; Mirjam Bedaf; Henny W. Verharen; Wout Slob; Georges R. Mohn; Barbara Hoebee; Jan van Benthem

1999-01-01

134

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, Fml; Lobo, Ch; Menezes, Esb; Rego, Jpa; Oliveira, Rv; Lima-Souza, Ac; Fioramonte, M; Gozzo, Fc; Pompeu, Rcff; Cândido, Mjd; Oliveira, Jt; Moura, Aa

2014-06-01

135

Utilisation of a sperm quality analyser to evaluate sperm quantity and quality of turkey breeders.  

PubMed

1. A relatively new instrument known as a Sperm Quality Analyzer (SQA) offers a rapid assessment of sperm quality and quantity by providing a sperm quality index (SQI). The SQA measures a combination of the intensity of sperm activity and motile concentration by determining the number and amplitude of sperm movements per second in a capillary tube as detected through light beam interference. 2. Because the SQA has not been tested for its potential use in turkeys, the objective was to determine if the SQA could accurately respond to changes in turkey sperm concentration, viability, and motility in semen collected from turkey breeders. 3. The effect of varying concentrations of sperm on SQI values was evaluated by diluting replicate pools of semen from 4 different aged turkey breeder flocks with saline. Results from all 4 flocks showed that semen dilutions greater than 20-fold resulted in a linear decline in SQI values. 4. Additional in vitro analysis evaluated the effects of turkey sperm viability on the SQI under conditions of constant sperm concentration. Incubated, live sperm was mixed in various proportions with thawed, dead sperm to determine changes in viability. Increased proportions of dead sperm caused a decline in the SQI. 5. To assess sperm motility, turkey semen was incubated under either aerobic (motile) or anaerobic (immotile) conditions. Varied amounts of immotile and motile sperm samples were mixed. A linear increase in the SQI was observed as per cent motile sperm increased. 6. These results indicate that the SQA can respond to differences in turkey sperm concentration, viability, and motility using in vitro analyses. PMID:12195806

Neuman, S L; McDaniel, C D; Frank, L; Radu, J; Einstein, M E; Hester, P Y

2002-07-01

136

Sperm storage and sperm competition across ovarian cycles in the dragon lizard, Ctenophorus fordi.  

PubMed

Female sperm storage can influence male reproductive success and may favour males that produce sperm that remain viable across several ovarian cycles. Here we show that sperm are viable in the female reproductive tract across ovarian cycles in the mallee dragon, Ctenophorus fordi. Based on experimental mating trials, we show that stored sperm were generally less likely to fertilize eggs than recently inseminated sperm. The fertilization success of stored sperm increased with male body size relative to rivals. This may be due to differences in ejaculate volume or sperm number transferred by males of different sizes. However, there was no evidence that copulation time, which is correlated with ejaculate volume, contributed to fertilization success. We suggest that sperm storage across ovarian cycles may be common in small, multi-clutched lizards and that its impact on selection on male phenotypes could contribute to the evolution of lizard mating systems. PMID:23744523

Uller, Tobias; Schwartz, Tonia; Koglin, Troy; Olsson, Mats

2013-08-01

137

Computer-assisted sperm analysis (CASA): capabilities and potential developments.  

PubMed

Computer-assisted sperm analysis (CASA) systems have evolved over approximately 40 years, through advances in devices to capture the image from a microscope, huge increases in computational power concurrent with amazing reduction in size of computers, new computer languages, and updated/expanded software algorithms. Remarkably, basic concepts for identifying sperm and their motion patterns are little changed. Older and slower systems remain in use. Most major spermatology laboratories and semen processing facilities have a CASA system, but the extent of reliance thereon ranges widely. This review describes capabilities and limitations of present CASA technology used with boar, bull, and stallion sperm, followed by possible future developments. Each marketed system is different. Modern CASA systems can automatically view multiple fields in a shallow specimen chamber to capture strobe-like images of 500 to >2000 sperm, at 50 or 60 frames per second, in clear or complex extenders, and in <2 minutes, store information for ? 30 frames and provide summary data for each spermatozoon and the population. A few systems evaluate sperm morphology concurrent with motion. CASA cannot accurately predict 'fertility' that will be obtained with a semen sample or subject. However, when carefully validated, current CASA systems provide information important for quality assurance of semen planned for marketing, and for the understanding of the diversity of sperm responses to changes in the microenvironment in research. The four take-home messages from this review are: (1) animal species, extender or medium, specimen chamber, intensity of illumination, imaging hardware and software, instrument settings, technician, etc., all affect accuracy and precision of output values; (2) semen production facilities probably do not need a substantially different CASA system whereas biology laboratories would benefit from systems capable of imaging and tracking sperm in deep chambers for a flexible period of time; (3) software should enable grouping of individual sperm based on one or more attributes so outputs reflect subpopulations or clusters of similar sperm with unique properties; means or medians for the total population are insufficient; and (4) a field-use, portable CASA system for measuring one motion and two or three morphology attributes of individual sperm is needed for field theriogenologists or andrologists working with human sperm outside urban centers; appropriate hardware to capture images and process data apparently are available. PMID:24274405

Amann, Rupert P; Waberski, Dagmar

2014-01-01

138

The Effects of Four Insect Growth-Regulating (IGR) Insecticides on Honeybee ( Apis mellifera L.) Colony Development, Queen Rearing and Drone Sperm Production  

Microsoft Academic Search

This study assessed the effects of exposure to IGRs on the long-term development of the honeybee colony, viability of queens\\u000a and sperm production in drones and integrated the data into a honeybee population model. Colonies treated with diflubenzuron\\u000a resulted in a short-term reduction in the numbers of adult bees and brood. Colonies treated with fenoxycarb declined during\\u000a the season earlier

Helen M. Thompson; Selwyn Wilkins; Alastair H. Battersby; Ruth J. Waite; David Wilkinson

2005-01-01

139

Low amounts of mitochondrial reactive oxygen species define human sperm quality.  

PubMed

We have applied the mitochondria-specific superoxide fluorescent probe MitoSOX Red (MitoSOX) to detect mitochondria-specific reactive oxygen species (mROS) production in human sperm samples using flow cytometry. We show that human ejaculates are heterogeneous in terms of mROS production, with three subpopulations clearly detectable, comprising sperm that produce increasing amounts of mROS (MitoSOX-, MitoSOX+, and MitoSOX++). The sperm subpopulation producing the lowest amount of mROS represented the most functional subset of male gametes within the ejaculate, as it was correlated with the highest amount of live and non-apoptotic sperm and increased both in samples with better semen parameters and in samples processed by both density-gradient centrifugation and swim-up, both known to select for higher quality sperm. Importantly, the MitoSOX- subpopulation was clearly more prevalent in samples that gave rise to pregnancies following assisted reproduction. Our work, therefore, not only describe discreet human sperm heterogeneity at the mROS level but also suggests that mROS may represent a strategy to both evaluate sperm samples and isolate the most functional gametes for assisted reproduction.FREE PORTUGUESE ABSTRACT: A Portuguese translation of this abstract is freely available at http://www.reproduction-online.org/content/147/6/817/suppl/DC1. PMID:24534950

Marques, Mónica; Sousa, Ana Paula; Paiva, Artur; Almeida-Santos, Teresa; Ramalho-Santos, João

2014-06-01

140

Artificial insemination with donor sperm (AID): heterogeneity in sperm banking facilities in a single country (Belgium)  

PubMed Central

Due to the high inflow of foreign patients seeking cross-border reproductive care in Belgium and the increased number of lesbian couples and single women who call for artificial insemination with donor sperm (AID), Belgian sperm banks nowadays face a shortage in donor sperm. However, since there is no central registration system for sperm donors in Belgium, no figures are currently available supporting this statement. Therefore a study was performed to obtain a detailed overview of the sperm banking facilities in Belgium. Questionnaires were sent to all Belgian centres for assisted reproduction with laboratory facilities (n?=?18) to report on their sperm banking methods. The results showed that 82% of the centres rely partially or completely on foreign donor sperm. Moreover, four of the thirteen centres that have their own sperm bank use imported donor sperm in >?95% AID cycles. Our results show that in 63% of the Belgian AID cycles imported Danish donor sperm is being used. Donor recruitment is mainly performed through the centre’s website (61%) or by distributing flyers in the centre (46%) and 9 to 180 potential donors have been recruited per centre in 2013. Eventually, 15 to 50% of these candidate donors were accepted. Different criteria for donor acceptance are handled by the centres: donor age limits range from 18-25 to 36-46 years old, and thresholds for sperm normality differ considerably. We can conclude that a wide variation in methods associated with sperm banking is observed in Belgian centres.

Thijssen, A.; Dhont, N.; Vandormael, E.; Cox, A.; Klerkx, E.; Creemers, E.; Ombelet, W.

2014-01-01

141

Improvement of European eel sperm cryopreservation method by preventing spermatozoa movement activation caused by cryoprotectants  

Microsoft Academic Search

Sperm production has been obtained from European and Japanese eels, but its quality and quantity tend to be changeable. So, its cryopreservation has been tried in both species. Dimethyl sulfoxide (Me2SO) is the best cryoprotectant for European eel sperm, but increases the medium osmolality, inducing the activation of spermatozoa motility. To avoid this, different combinations of pH (6.5 and 8.5)

D. S. Peñaranda; L. Pérez; V. Gallego; M. Jover; J. F. Asturiano

2009-01-01

142

Methodological advances in sperm proteomics.  

PubMed

Proteomics is the study of the proteins of cells or tissues. Sperm proteomics aims to identify the proteins that compose the sperm cell and the study of their function. Recent developments in mass spectrometry (MS) have markedly increased the throughput to identify and study sperm proteins. Catalogues of hundreds to thousands of spermatozoan proteins in human and in model species are becoming available setting up the basis for subsequent research, diagnostic applications and the development of specific treatments. A wide range of MS techniques are also rapidly becoming available for researchers. The present review summarises the different methodological options to study the sperm cell using MS and to provide a summary of some of the ongoing proteomic studies. PMID:21117936

Oliva, Rafael; De Mateo, Sara; Castillo, Judit; Azpiazu, Rubén; Oriola, Josep; Ballescà, Josep Lluís

2010-12-01

143

Detecting and minimizing sperm DNA damage.  

PubMed

In recent years, with the advancement in sperm cell biology and the development of additional testing techniques, sperm DNA fragmentation has been recognized as one of the important causes of reduced fertility potential. Elevated sperm DNA fragmentation rates also significantly diminish the chance of success in assisted pregnancies. Sperm DNA damage can impair fertilization, disrupt embryonic development, and increase rates of miscarriage and poor conception rates. Newer studies suggest the possibility of an increased risk of childhood cancer when an embryo develops from DNA-damaged sperm. There is limited data from large, randomized, controlled trials to support improvement in male fertility with current interventions such as antioxidant therapy, varicocelectomy, and antibiotics treatment in genital tract infections. Nonetheless, research efforts have shown improvements in semen parameters and these interventions are low risk. Therefore, when the external risk factors are known, every effort should be made to minimize sperm DNA damage. PMID:23775382

Zhang, Yachao; Trussell, J C; Chohan, Kazim R

2013-07-01

144

Understanding email interaction increases organizational productivity  

Microsoft Academic Search

To minimize the effect of email interruption on employee productivity, limit the frequency of new-email alerts (silence them, too), make it easier to assess each message's importance, and remove the reply-to-all facility.

Thomas W. Jackson; Ray Dawson; Darren Wilson

2003-01-01

145

Products to safely increase lean muscle mass.  

PubMed

Pharmaceutical companies are promoting injectable HGH or rHGH to promote the gain of muscle mass in persons with AIDS. Side effects can include high triglycerides, thyroid dysfunction, and increased tumor growth. A possible alternative is a Homeopathic HGH produced by Biomed Comm. Contact information for Biomed Comm is provided. Marinol, which contains THC, the active ingredient in marijuana, also promotes appetite and an increase in body mass. Immunocal, Optimune, and Designer Protein also appear effective in increasing lean muscle mass. Whole lemon olive oil drink is also discussed. PMID:11366553

1998-01-01

146

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

147

Sperm trajectories form chiral ribbons.  

PubMed

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

148

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.

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

2011-01-01

149

Cytometry of mammalian sperm  

SciTech Connect

Male germ cells respond dramatically to a variety of insults and are important reproductive dosimeters. Semen analyses are very useful in studies on the effects of drugs, chemicals, and environmental hazards on testicular function, male fertility and heritable germinal mutations. The accessibility of male cells makes them well suited for analytical cytology. We might automate the process of determining sperm morphology but should not do so solely for increased speed. Rather, richer tangible benefits will derive from cytometric evaluation through increased sensitivity, reduced subjectivity, standardization between investigators and laboratories, enhanced archival systems, and the benefits of easily exchanged standardized data. Inroads on the standardization of assays for motility and functional integrity are being made. Flow cytometric analysis of total DNA content of individual sperm is an insensitive means to detect exposure to reproductive toxins because of the small size and low frequency of the DNA content errors. Flow cytometry can be applied to determine the proportions of X- and Y-sperm in semen samples.

Gledhill, B.L.

1983-10-11

150

Investigation on dispermic androgenesis in sturgeon fish. The first successful production of androgenetic sturgeons with cryopreserved sperm  

Microsoft Academic Search

Induced diploid androgenesis is considered as a valuable tool for restoration of endangered or extinct species from cryopreserved spermatozoa. The method of dispermic androgenesis was developed in sturgeon fishes whose threatened status requires urgent conservation efforts. The method includes genetic inactivation of eggs, their insemination with concentrated sperm (to cause polyspermy), and the heat shock that facilitates the fusion of

A. S. Grunina; A. V. Recoubratsky; L. I. Tsvetkova; V. A. Barmintsev

2006-01-01

151

Effect of 655nm laser different powers on dog sperm motility parameters  

NASA Astrophysics Data System (ADS)

Introduction: One of the most appreciated features of the sperm is its motility, which depends on a big energy consumption despite differences among species. Laser acts direct or indirectly on mitochondria increasing ATP production. Material and method: By means of a Computer Aided Sperm Analysis (CASA) we have studied the effects of a 655 nm continuous wave diode laser irradiation at different power outputs with a dose of 3.3418 J on sperm motility. After an eosine-nigrosine stain to establish its quality, the second fraction of fresh beagle dog sperm was divided into 5 groups, 1 control and four to be irradiated respectively with an average output power of 6.84 mW, 15.43 mW, 33.05 mW and 49.66 mW. At times 0 and 45 minutes from irradiation pictures were taken and analysed with the Sperm class Analyzer SCA2002 programme. The motility parameters of 4987 spermatozoa studied were: curvilinear velocity (VCL), progressive velocity (VSL), straightness (STR), wobble (WOB), average path velocity (VAP), linearity (LIN), mean amplitude of lateral head displacement (ALHmed), beat cross frequency (BCF) and the total motility (MT). At time 15 minutes after irradiation a hypoosmotic swelling test (HOST) was done. Results: Several motility parameters that affect the overall motile sperm subpopulation structure have been changed by different output powers of a 655 nm diode laser irradiation, and prevents the decrease of the sperm motility properties along time.

Corral-Baqués, M. I.; Rigau, T.; Rivera, M. M.; Rodríguez-Gil, J. E.; Rigau, J.

2006-05-01

152

Coal liquefaction to increase jet fuel production  

NASA Technical Reports Server (NTRS)

Processing concept that increases supply of jet fuel has been developed as part of study on methods for converting coal to hydrogen, methane, and jet fuel. Concept takes advantage of high aromatic content of coal-derived liquids to make high-octane gasoline, instead of destroying aromatics to make jet fuel.

1979-01-01

153

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

154

Sperm numbers, their storage and usage in the fly Dryomyza anilis  

PubMed Central

In the fly Dryomyza anilis females have two kinds of sperm storage organs: one bursa copulatrix and three spermathecae (two spermathecae with a common duct form the doublet, and the third is a singlet spermathecal unit). At the beginning of a mating the male deposits his sperm in the bursa copulatrix. After sperm transfer the male taps the female's abdomen with his claspers. This behaviour has been shown to increase the male's fertilization success. After mating, the female discharges large quantities of sperm before oviposition. To find out where the sperm remaining in the female are stored, I counted the number of sperm in the droplet and in the female's sperm storage organs after different types of mating. I carried out three mating experiments. In experiment 1, virgin females were mated with one male and the matings were interrupted either immediately after sperm transfer or after several tapping sequences. The results show that during male tapping more sperm moved into the singlet spermatheca. In addition, the total number of sperm correlated with sperm numbers in all sperm storage organs, and male size was positively related to the number of sperm remaining in the bursa. In experiment 2, females mated with several males. The number of sperm increased with increasing number of matings only in the doublet spermatheca. No increase in the number of sperm in the singlet spermatheca during consecutive matings suggests that sperm were replaced or did not reach this sperm storage organ. In experiment 3, virgin females were mated with a single male and half of them were allowed to lay eggs. The experiment showed that during egglaying, females primarily used sperm from their singlet spermatheca. The results from the three experiments suggest that sperm stored in the singlet spermatheca is central for male fertilization success and male tapping is related to sperm storage in the singlet spermatheca. The different female's sperm storage organs in D. anilis may have separate functions during sperm storage as well as during sperm usage.

Otronen, M.

1997-01-01

155

Thawing and processing of cryopreserved bovine spermatozoa at various temperatures and their effects on sperm viability, osmotic shock and sperm membrane functional integrity  

Microsoft Academic Search

The objective of this study was to evaluate the effects of thawing and processing temperatures on post-thaw sperm viability, occurrence of osmotic shock and sperm membrane functional status. The occurrence of osmotic shock, characterized by increased spermatozoa with coiled tails, eventually results in reduced sperm viability and sperm membrane integrity. The effects of different thawing temperatures were assessed by thawing

J. R. Correa; M. C. Rodriguez; D. J. Patterson; P. M. Zavos

1996-01-01

156

Epoxiconazole causes changes in testicular histology and sperm production in the Japanese quail (Coturnix coturnix japonica).  

PubMed

The fungicide epoxiconazole (Epox), a triazole, belongs to the group of azole compounds that are extensively used as fungicides in various fruit crops. The frequent use of agricultural lands for wintering by migrating birds can be the source of their increased dietary intake of agricultural pesticides. We investigated whether exposure to Epox causes effects on avian fertility and reproduction, using the Japanese quail (Coturnix coturnix japonica) as a model species for the assessment of reproductive effects of pesticides in wild birds. Epox was administered to adult Japanese quail for three weeks at dietary levels of 10, 50, and 500 ppm, and possible effects on reproduction were investigated. Epox administration resulted in a significantly decreased number of spermatids in the 50- and 500-ppm dose groups. Histopathology showed a reduced number of testicular canaliculi with visible germ cells and a reduction in spermatid number. However, testis weight was not affected up to the highest dose level. No impact was observed on hormone levels, fertility, and reproductive outcome, as laying rate and percentage of fertile eggs were not altered. Likewise, treatment had no influence on the egg or chick parameters evaluated. A time- and dose-related transfer of Epox into the eggs was determined in all treatment groups. We conclude that dietary treatment of Japanese quail with 50 and 500 ppm of the triazole fungicide Epox resulted in a clear impact on the testis. The evaluation of the additional endpoints spermatid count and testicular histology have proven useful and are recommended for future studies on avian reproduction. PMID:18522476

Grote, Konstanze; Niemann, Lars; Selzsam, Britta; Haider, Wolfgang; Gericke, Christine; Herzler, Matthias; Chahoud, Ibrahim

2008-11-01

157

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

158

The ecological and evolutionary consequences of sperm chemoattraction  

Microsoft Academic Search

Chemical communication between sperm and egg is a critical factor mediating sexual reproduction. Sperm attractants may be signifi- cant evolutionarily for maintaining species barriers, and important ecologically for increasing gamete encounters. Still unresolved, however, are the functional consequences of these dissolved signal molecules. Here, we provide experimental evidence that sperm chemoattraction directly affects the magnitude of fertilization success. The recent

Jeffrey A. Riffell; Patrick J. Krug; Richard K. Zimmer

2004-01-01

159

The ecological and evolutionary consequences of sperm chemoattraction  

Microsoft Academic Search

Chemical communication between sperm and egg is a critical factor mediating sexual reproduction. Sperm attractants may be significant evolutionarily for maintaining species barriers, and important ecologically for increasing gamete encounters. Still unresolved, however, are the functional consequences of these dissolved signal molecules. Here, we provide experimental evidence that sperm chemoattraction directly affects the magnitude of fertilization success. The recent discovery

Jeffrey A. Riffell; Patrick J. Krug; Richard K. Zimmer

2004-01-01

160

[Dispermic androgenesis in sturgeons with the help of cryopreserved sperm: production of androgenetic hybrids between Siberian and Russian sturgeons].  

PubMed

Dispermic androgenesis was used to produce, for the first time, an androgenetic progeny of the Siberian sturgeon (Acipenser baerii) and the androgenetic nuclear cytoplasmic hybrids (Siberian sturgeon, A. baerii x Russian sturgeon, A. gueldenstaedtii) using cryopreserved sperm. Microsatellite DNA analysis confirmed exclusively paternal inheritance in the androgenetic progeny of Siberian sturgeon. Heterozygotes for certain microsatellite loci were detected among the androgenetic hybrids, thereby confirming a dispermic nature of androgenesis. According to the data of comparative morphological analysis, the obtained androgenetic hybrid, by the age of 15 months old, was completely identical to the paternal species. Both a female and a male were detected in the androgenetic sturgeon progenies, which is of interest for producing bisexual progenies via androgenesis. The data of this study confirm the feasibility of dispermic androgenesis using cryopreserved sperm to preserve and recover the gene pools of endangered sturgeon species. PMID:21542342

Grunina, A S; Rekubratski?, A V; Tsvetkova, L I; Barmintseva, A E; Vasil'eva, E D; Kovalev, K V; Poluéktova, O G

2011-01-01

161

Use of grayling sperm (Thymallus thymallus) as a marker for the production of gynogenetic rainbow trout (Salmo gairdneri).  

PubMed

Experiments were conducted to estimate the viability of diploid and induced triploid hybrids between the rainbow trout female and the grayling male. Both are unable to hatch, even so the triploid dies later than the diploid. Insemination of rainbow trout eggs by UV irradiated sperm of grayling results in gynogenetic rainbow trouts when viability is restored by heat shocks inhibiting the second division of egg meiosis. PMID:24248073

Chourrout, D

1986-08-01

162

Intracytoplasmic Sperm Injection (ICSI)  

MedlinePLUS

... the use of traditional IVF has not produced fertilization, regardless of the condition of the sperm. Will ... with sperm • The embryo may stop growing Once fertilization takes place, a couple's chance of giving birth ...

163

EVIDENCE FAVORING SPERM SELECTION OVER SPERM COMPETITION IN THE INTERACTION BETWEEN HUMAN SEMINAL PLASMA AND SPERM MOTILITY IN VITRO  

Microsoft Academic Search

& The effect on sperm motility of sperm-sperm and sperm-seminal plasma interactions was stud- ied among homologous and heterologous sperm. There were no significant interactions between sperm in vitro, but it was found that seminal plasmas of different donors have different effects on sperm motility, and different sperm react differently to the same seminal plasma. Sperm showed higher motility in

K. Jaffe; M. I. Camejo; T. E. Carrillo; M. Weffer; M. G. Muñoz

2006-01-01

164

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

165

Sperm Whales (Physeter catodon) React to Pingers.  

National Technical Information Service (NTIS)

Sperm whales, Physeter catodon, temporarily interrupted their own sound production in reaction to underwater pulses produced by our calibration sound sources (pingers). All seven whales that passed close to the hydrophone array at different times reacted ...

W. A. Watkins W. E. Schevill

1974-01-01

166

Aquaporin3 is a sperm water channel essential for postcopulatory sperm osmoadaptation and migration.  

PubMed

In the journey from the male to female reproductive tract, mammalian sperm experience a natural osmotic decrease (e.g., in mouse, from ~415 mOsm in the cauda epididymis to ~310 mOsm in the uterine cavity). Sperm have evolved to utilize this hypotonic exposure for motility activation, meanwhile efficiently silence the negative impact of hypotonic cell swelling. Previous physiological and pharmacological studies have shown that ion channel-controlled water influx/efflux is actively involved in the process of sperm volume regulation; however, no specific sperm proteins have been found responsible for this rapid osmoadaptation. Here, we report that aquaporin3 (AQP3) is a sperm water channel in mice and humans. Aqp3-deficient sperm show normal motility activation in response to hypotonicity but display increased vulnerability to hypotonic cell swelling, characterized by increased tail bending after entering uterus. The sperm defect is a result of impaired sperm volume regulation and progressive cell swelling in response to physiological hypotonic stress during male-female reproductive tract transition. Time-lapse imaging revealed that the cell volume expansion begins at cytoplasmic droplet, forcing the tail to angulate and form a hairpin-like structure due to mechanical membrane stretch. The tail deformation hampered sperm migration into oviduct, resulting in impaired fertilization and reduced male fertility. These data suggest AQP3 as an essential membrane pathway for sperm regulatory volume decrease (RVD) that balances the "trade-off" between sperm motility and cell swelling upon physiological hypotonicity, thereby optimizing postcopulatory sperm behavior. PMID:21135872

Chen, Qi; Peng, Hongying; Lei, Li; Zhang, Ying; Kuang, Haibin; Cao, Yujing; Shi, Qi-Xian; Ma, Tonghui; Duan, Enkui

2011-06-01

167

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.

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

2009-01-01

168

Optimizing production of in vivo-matured oocytes from superstimulated Holstein cows for in vitro production of embryos using X-sorted sperm.  

PubMed

The present study aimed to establish an efficient system for the production of female embryos from dairy cows by in vitro fertilization (IVF) using X-sorted sperm and in vivo-matured oocytes collected by ovum pick up (OPU). Nonlactating Holstein cows (n=36) were administered a controlled intravaginal progesterone-releasing (controlled internal drug release) device (d 0), underwent dominant follicle ablation (DFA) or ovulation by administration of 100?g of GnRH on d 5, and were superstimulated with FSH and PGF2?, following standard procedures. Controlled internal drug release devices were removed on the evening of d 8 or on the morning of d 9, depending on the experiment. For LH surge induction, 200?g of GnRH was administered on the morning of d 10 (0h). In experiment 1, the peak (48.1%) of ovulating follicles was detected at 29 to 32h after GnRH injection (0h), and the range in the timing of the initiation of ovulation was less by timing from GnRH administration (30.0±2.8h) rather than by timing the onset of estrus (32.7±4.7h). Only 0.9% of total ovulated follicles were recorded before 26h after GnRH injection. Therefore, OPU was carried out at 26h and IVF occurred at 30h after GnRH in experiments 2 and 3. In experiment 2, 83.3±10.8% of oocytes with expanded cumulus cells had extruded the first polar body at 30h after GnRH injection. The aim of experiment 3 was to compare the effect of either DFA or GnRH-induced LH surge before superstimulation on the efficiency of embryo production by IVF following superstimulation. Progesterone concentrations from d 10 to 12 in the DFA group were lower than those in the GnRH group. A greater proportion of recovered oocytes with expanded cumulus cells from ?8-mm follicles was observed in the DFA group than in the GnRH group (95.9 and 77.4%, respectively). Blastocyst rates in the DFA and GnRH groups (58.0 and 52.8%, respectively) did not differ from those of oocytes collected from nonstimulated OPU and matured in vitro (49.9%). However, the proportion of high-quality blastocysts was higher in the DFA group compared with the GnRH group (54.9 vs. 21.5%). Our results demonstrate that high rates of good-quality blastocysts can be produced by IVF with X-sorted frozen sperm using in vivo-matured oocytes collected by OPU from cows after DFA and superstimulation combined with ovulation induction. PMID:24290822

Matoba, S; Yoshioka, H; Matsuda, H; Sugimura, S; Aikawa, Y; Ohtake, M; Hashiyada, Y; Seta, T; Nakagawa, K; Lonergan, P; Imai, K

2014-02-01

169

Methods of increasing hydrocarbon production from subterranean formations  

SciTech Connect

Methods of increasing hydrocarbon production from subterranean hydrocarbon-containing formations are provided. The formations are contacted with cationic perfluoro compounds. The formula for these compounds is given.

Penny, G.S.; Briscoe, J.E.

1982-01-10

170

Rapid adjustments of sperm characteristics in relation to social status.  

PubMed

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

2006-02-01

171

Drosophila Sperm Motility in the Reproductive Tract1  

PubMed Central

Motile cilia and flagella exhibit many waveforms as outputs of dynein activation sequences on the highly conserved axoneme. Motility change of sperm in the reproductive tract is difficult to study and remains an important area of investigation. Sperm typically execute a sinusoidal waveform. Increased viscosity in the medium induces somewhat unusual arc-line and helical waveforms in some sperm. However, whether the latter two waveforms occur in vivo is not known. Using green fluorescence protein imaging, we show that Drosophila sperm in the uterus move in circular foci via arc-line waves, predominantly in a tail-leading orientation. From the uterus, a small fraction of the sperm enters the seminal receptacle (SR) in parallel formations. After sperm storage and coincident with fertilization of the egg, the sperm exit the SR via head-leading helical waves. Consistent with the observed bidirectional movements, the sperm show the ability to propagate both base-to-tip and tip-to-base flagellar waves. Numerous studies have shown that sperm motility is regulated by intraflagellar calcium concentrations; in particular, the Pkd2 calcium channel has been shown to affect sperm storage. Our analyses here suggest that Pkd2 is required for the sperm to adopt the correct waveform and movement orientation during SR entry. A working model for the sperm's SR entry movement is proposed.

Yang, Yong; Lu, Xiangyi

2011-01-01

172

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

173

Immune activation decreases sperm viability in both sexes and influences female sperm storage  

PubMed Central

All animals are under the constant threat of pathogenic infection. However, little is known regarding the influence of acute infection on sperm viability, particularly in female insects. This information is crucial for our understanding of mating and immune system coevolution, considering that females store sperm and serve as the site of sperm competition. Using the fruitfly, Drosophila melanogaster, we examined the influence of infection on sperm viability and storage. Twenty-four hours after haemocoel inoculation with a pathogen mimic (peptidoglycan, PGN) both sexes exhibited reduced sperm viability, indicating that systemic immune activation played a significant role in gamete survival. Surprisingly, sperm death did not appear to result from a reproductive-immune system trade-off, considering that sperm survived 24 h in vitro once removed from their somatic resources. Instead, our results are most consistent with death owing to immune effector collateral damage. We also examined the potential for sexually transmitted pathogens to influence sperm storage. Females mated with ‘infected’ males (created by dipping genitalia into a PGN solution) exhibited a higher proportion of empty sperm stores 48 h after mating compared to their controls. Remarkably, these data indicate that females may increase their fitness by removing ‘infected’ ejaculates from storage over time.

Radhakrishnan, Preethi; Fedorka, Kenneth M.

2012-01-01

174

Sperm competition in a fish with external fertilization: the contribution of sperm number, speed and length.  

PubMed

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 incorporating these males' mean proximity to eggs and timing of sperm release. Using a maximum-likelihood algorithm, raffle equations were fit to paternity data, which revealed a strong effect of sperm number on male competitiveness. There was no difference in sperm flagellum length, curvilinear swim speed or path linearity among the three male mating types, and these traits did not explain any additional variation in male competitiveness. It was estimated that, given closer proximity to eggs, satellites need release only 0.34 times as many sperm as parentals to obtain equal paternity. Despite being farther from the eggs and releasing sperm about half a second after parentals, sneakers need only release 0.58 times as many sperm as parentals to obtain equal paternity. Thus, the increased competitiveness of sneakers' sperm must come from a component of sperm quality other than speed or length. PMID:17040384

Stoltz, J A; Neff, B D

2006-11-01

175

Sperm competition affects male behaviour and sperm output in the rainbow darter  

PubMed Central

Rainbow darters, Etheostoma caeruleum, are promiscuous fish with moderate rates of group spawning (between one and five males may simultaneously mate with one female). In this study, I examined male sperm output and male willingness to spawn under different levels of sperm competition intensity. One male and one female were allowed to spawn in an aquarium where they had visual and olfactory access to one of four treatments: four males, one male, zero males, or one female. Theory predicts that males should reduce sperm output when there are more than the average number of males at a group spawning (four-male treatment) and should increase sperm output when there are fewer than average males at a group spawning (one-male treatment). Mean sperm output did not differ among treatments. However, males released more sperm when spawning in the presence of competing males (four-male and one-male treatments pooled) than when spawning in the absence of competing males (zero-male and one-female treatments pooled). Males were also most likely to forego spawning opportunities when sperm competition intensity was high. Furthermore, male willingness to spawn was size dependent. Large males were more likely to forego spawning opportunities under high sperm competition intensity. Large males may be better off waiting for future spawning opportunities when there is a lower potential for sperm competition intensity.

Fuller, R. C.

1998-01-01

176

Consequences of sperm displacement for female dung flies, Scatophaga stercoraria  

PubMed Central

Displacement of stored sperm during copulation occurs in many insects. This process provides direct benefits for males via increased fertilization success, but the fitness consequences of sperm displacement for females are less clear. Here we investigate potential benefits of sperm displacement for female yellow dung flies, Scatophaga stercoraria. We find no evidence that female dung flies gain direct benefits from displacement of previously stored sperm in terms of increased fertility or fecundity. There was no difference in the relative survival rate, development time, size or fluctuating asymmetry of offspring produced by females that had previously stored sperm displaced before oviposition and those that did not. Females using previously stored sperm to fertilize their eggs produced significantly higher ratios of male to female offspring. These novel findings have important implications for understanding the evolutionary dynamics of male–female interactions in sperm competition.

Stockley, P.; Simmons, L. W.

1998-01-01

177

Atropine-induced inhibition of sperm and semen transport impairs fertility in male rats.  

PubMed

Previous studies revealed that atropine reduced male fertility in rats without any effects on mating performance, sperm production and motility, and testicular morphology. The present study was conducted to investigate whether the impairment of male fertility induced by atropine was related to the inhibition of sperm and semen transports from the vas deferens and seminal vesicle to the urethra during the process of emission. Male rats were treated with atropine at 125 mg/kg/day for 10-17 days prior to mating with untreated females. After confirmation of mating, male rats were euthanized and sperm number in the vas deferens and weights of the seminal vesicle and copulatory plug were determined as indicators of inhibition of sperm and semen transports, respectively. Reproductive status of mated females was determined on gestation days 15-17. A low pregnancy rate associated with a decreased number of implants was observed in females that mated with the atropine-treated males. The average number of sperm in the vas deferens was increased in the atropine-treated males. The average seminal vesicle weight in the atropine-treated males was greater than that of controls. The copulatory plug weights were decreased in the atropine-treated males. These results suggest that inhibitions of sperm and semen transports from the vas deferens and seminal vesicle to the urethra during the process of emission result in reduced male fertility in rats. PMID:16141654

Sato, Takahiro; Ban, Yoshiki; Uchida, Miki; Gondo, Eri; Yamamoto, Masakatsu; Sekiguchi, Yoshiko; Sakaue, Akiko; Kemi, Masayuki; Nakatsuka, Toshio

2005-08-01

178

State Policies and Planning to Increase Attainment, Quality, and Productivity  

ERIC Educational Resources Information Center

This article examines why state planning and policy for higher education are increasingly focused on increasing educational attainment, quality, and the productivity of the system. It presents four "stories" which illustrate initiatives to improve attainment, quality, and productivity, but fall far short of exhausting the available material.

Lingenfelter, Paul E.

2007-01-01

179

Sperm activation by heat shock protein 70 supports the migration of sperm released from sperm storage tubules in Japanese quail (Coturnix japonica).  

PubMed

Systems for maintaining the viability of ejaculated sperm in the female reproductive tract are widespread among vertebrates and invertebrates. In birds, this sperm storage function is performed by specialized simple tubular invaginations called sperm storage tubules (SSTs) in the uterovaginal junction (UVJ) of the oviduct. Although the incidence and physiological reasons for sperm storage in birds have been reported extensively, the mechanisms of sperm uptake by the SSTs, sperm maintenance within the SSTs, and control of sperm release from the SSTs are poorly understood. In this study, we demonstrated that the highly conserved heat shock protein 70 (HSP70) stimulates sperm motility in vitro and also that HSP70 expressed in the UVJ may facilitate the migration of sperm released from the SSTs. Quantitative RT-PCR analysis demonstrated that the expression of HSP70 mRNA in the UVJ increases before ovulation/oviposition. Gene-specific in situ hybridization and immunohistochemical analysis with a specific antibody to HSP70 demonstrated that HSP70 is localized in the surface epithelium of the UVJ. Furthermore, injection of anti-HSP70 antibody into the vagina significantly inhibited fertilization in vivo. In addition, we found that recombinant HSP70 activates flagellar movement in the sperm and that the binding of recombinant HSP70 to the sperm surface is mediated through an interaction with voltage-dependent anion channel protein 2 (VDAC2). Our results suggest that HSP70 binds to the sperm surface by interacting with VDAC2 and activating sperm motility. This binding appears to play an important role in sperm migration within the oviduct. PMID:24194572

Hiyama, Gen; Matsuzaki, Mei; Mizushima, Shusei; Dohra, Hideo; Ikegami, Keisuke; Yoshimura, Takashi; Shiba, Kogiku; Inaba, Kazuo; Sasanami, Tomohiro

2014-02-01

180

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

181

Developmental exposure to decabrominated diphenyl ether (BDE-209): effects on sperm oxidative stress and chromatin DNA damage in mouse offspring.  

PubMed

Polybrominated diphenyl ethers (PBDEs) are used as brominated flame retardants and have been found in human milk in recent years. This study investigates whether prenatal exposure to decabrominated diphenyl ether (BDE-209) induces sperm dysfunction in male offspring. Pregnant CD-1 mice were gavaged once daily with corn oil (control), 10, 500, and 1500 mg kg(-1) body weight of BDE-209 from day 0 of gestation to day 17. The outcomes of male reproductive parameters were assessed on postnatal day 71. Anogenital distance, sperm-head abnormalities, and testicular histopathology were significantly affected in male offspring prenatally exposed to 1500 mg kg(-1). Significant increases in the tendency for sperm DNA denaturation (?T) induction and the DNA fragmentation index (DFI) were found in those exposed to 10, 500, and 1500 mg kg(-1) (P < 0.05). We observed a significant increase of sperm hydrogen peroxide (H(2)O(2)) generation in the 10 and 1500 mg/kg/day groups compared to the control group (P < 0.05). Although our findings suggested that the mechanisms underlying BDE-209-induced sperm DNA damage and H(2)O(2) generation might not be represented as a dose-response relationship, we found that the greater the excess production of sperm H(2)O(2), the greater the sperm ?T (r = 0.65, P = 0.0155) and DFI (r = 0.53, P = 0.002). In conclusion, developmental exposure to BDE-209 induced sperm-head abnormality, oxidative stress, chromatin DNA damage, and testicular histopathological changes. These findings suggest that BDE-209-induced male reproductive effects might involve the formation of sperm H(2)O(2) which attacks nucleic acids via H(2)O(2) generation. PMID:21626651

Tseng, Li-Ho; Hsu, Ping-Chi; Lee, Chia-Wei; Tsai, Shinn-Shyong; Pan, Min-Hsiung; Li, Mei-Hui

2013-07-01

182

Delivering cholesterol or cholestanol to bull sperm membranes improves cryosurvival.  

PubMed

This study compared the effect of adding other cholesterol conjugates, which should incorporate into and increase sperm membrane fluidity at low temperatures thereby increasing cryosurvival. Ejaculates from each of four bulls were diluted to 120 million cells/ml in a Tris diluent and used in two experiments. Each experiment contained four treatments: No additive (control); 1.5mg CLC/120 million sperm (positive control); and 1.5mg cyclodextrin pre-loaded with cholestanol or desmosterol/120 million sperm. In the first experiment, fresh sperm were treated with cyclodextrins that were pre-loaded with cholesteryl conjugates and incubated for 15 min at 22 degrees C to allow incorporation of the conjugates. The percentages of motile sperm after exposure to solutions ranging from 0 to 1200 mOsm were used to evaluate the osmotic tolerance of the cells. The ability of treated sperm to bind to the bovine zona pellucida (ZP) and chicken egg perivitelline membrane (CEPM) was evaluated to determine if altering the sperm membrane affected the ability of sperm to bind to oocytes. In the final experiment, the cryosurvival rates of control and treated sperm were determined. Control and treated sperm were cryopreserved in a Tris diluent containing 10% egg yolk (EY) and 8% glycerol (final concentrations). Samples were thawed to determine the motility and ability of sperm to bind to the ZP and to CEPM using a CASA and epifluorescence microscope, respectively. Fresh sperm treated with CLC resulted in more binding to the ZP compared to all other treatments (P<0.05). No differences were observed between ZP and CEPM binding (P>0.05). The percentages of motile sperm were greater for fresh samples treated with cholesterol, cholestanol or desmosterol loaded cyclodextrin than control cells (P<0.05) when the sperm were exposed to anisosmotic conditions, and then returned to isosmolality. After cryopreservation the percentages of motile sperm and number of sperm binding to each CEPM were similar for sperm treated with CLC and cholestanol compared to sperm treated with desmosterol (P>0.05). All treatments provided greater motility and binding efficiency than control sperm (P<0.05). Therefore, adding cholesterol or cholestanol to bull sperm membranes improved cell cryosurvival. PMID:19733986

Moraes, E A; Graham, J K; Torres, C A A; Meyers, M; Spizziri, B

2010-04-01

183

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

2004-01-01

184

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.

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

2012-01-01

185

The Sperm Epigenome  

Microsoft Academic Search

\\u000a The development of male germ cells from the primordial germ cell stage to that of the mature spermatozoon is a key time of\\u000a epigenetic reprogramming. Orchestrated by specialized enzymes, DNA methylation and histone modifications undergo dynamic changes\\u000a throughout gametogenesis. Alterations to any level of the sperm epigenetic coding may affect fertility and the sperm’s contribution\\u000a to normal embryo development. In

Donovan Chan; Jacquetta Trasler

186

Transnational Regulation: Increasing the Safety of Globally Sourced Products  

Microsoft Academic Search

This seminar will explore ways to increase the safety of products produced through global supply chains and imported into the United States and Europe. Recent incidents indicate that globally sourced products can create serious safety issues and present regulatory challenges. Imports from global supply chains cross several borders and their regulation is affected by both national and international law. To

Vicki Bier; Lorna Zach

187

An ARID Domain-Containing Protein within Nuclear Bodies Is Required for Sperm Cell Formation in Arabidopsis thaliana  

PubMed Central

In plants, each male meiotic product undergoes mitosis, and then one of the resulting cells divides again, yielding a three-celled pollen grain comprised of a vegetative cell and two sperm cells. Several genes have been found to act in this process, and DUO1 (DUO POLLEN 1), a transcription factor, plays a key role in sperm cell formation by activating expression of several germline genes. But how DUO1 itself is activated and how sperm cell formation is initiated remain unknown. To expand our understanding of sperm cell formation, we characterized an ARID (AT-Rich Interacting Domain)-containing protein, ARID1, that is specifically required for sperm cell formation in Arabidopsis. ARID1 localizes within nuclear bodies that are transiently present in the generative cell from which sperm cells arise, coincident with the timing of DUO1 activation. An arid1 mutant and antisense arid1 plants had an increased incidence of pollen with only a single sperm-like cell and exhibited reduced fertility as well as reduced expression of DUO1. In vitro and in vivo evidence showed that ARID1 binds to the DUO1 promoter. Lastly, we found that ARID1 physically associates with histone deacetylase 8 and that histone acetylation, which in wild type is evident only in sperm, expanded to the vegetative cell nucleus in the arid1 mutant. This study identifies a novel component required for sperm cell formation in plants and uncovers a direct positive regulatory role of ARID1 on DUO1 through association with histone acetylation.

Zheng, Binglian; He, Hui; Zheng, Yanhua; Wu, Wenye; McCormick, Sheila

2014-01-01

188

Increasing Productivity for Autonomous Mass Excavation A Thesis Proposal  

Microsoft Academic Search

This research focuses on the problem of increasing productivity for the task of autonomous mass excavation. Autonomous excavation has the benefits of higher productivity, lower la- bor costs, increased safety, and the ability to work in hazardous environments. Mass exca- vation involves rapidly loading trucks with soil\\/rock\\/ore using a mobile digging machine with a bucket on an arm-like appendage. It

Patrick Rowe

1997-01-01

189

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.

Miki, Kiyoshi; Clapham, David E

2013-01-01

190

Foetal and post-natal exposure of sheep to sewage sludge chemicals disrupts sperm production in adulthood in a subset of animals.  

PubMed

Exposure to ubiquitous, environmental chemicals (ECs) has been hypothesized as a cause for declining male reproductive health. Understanding the long-term effects of EC exposure on reproductive health in humans requires animal models and exposure to 'real life', environmentally relevant, mixtures during development, a life stage of particular sensitivity to ECs. The aim of this study was to evaluate the effects of in utero and post-natal exposure to environmentally relevant levels of ECs, via sewage sludge application to pasture, on the adult male sheep testis. Hormones, liver concentrations of candidate ECs and Sertoli and germ cell numbers in testes of adult rams that were exposed to ECs in sewage sludge in utero, and until weaning via maternal exposure, and post-weaning via grazing pastures fertilized with sewage sludge, were quantified. Evaluated as a single group, exposure to sludge ECs was without significant effect on most parameters. However, a more detailed study revealed that 5 of 12 sludge-exposed rams exhibited major spermatogenic abnormalities. These consisted of major reductions in germ cell numbers per testis or per Sertoli cell and more Sertoli cell-only tubules, when compared with controls, which did not show any such changes. The sludge-related spermatogenic changes in the five affected animals were significantly different from controls (p < 0.001); Sertoli cell number was unaffected. Hormone profiles and liver candidate EC concentrations were not measurably affected by exposure. We conclude that developmental exposure of male sheep to real-world mixtures of ECs can result in major reduction in germ cell numbers, indicative of impaired sperm production, in a proportion of exposed males. The individual-specific effects are presumed to reflect EC effects on a heterogeneous population in which some individuals may be more susceptible to adverse EC effects. Such effects of EC exposure in humans could have adverse consequences for sperm counts and fertility in some exposed males. PMID:22150464

Bellingham, M; McKinnell, C; Fowler, P A; Amezaga, M R; Zhang, Z; Rhind, S M; Cotinot, C; Mandon-Pepin, B; Evans, N P; Sharpe, R M

2012-06-01

191

Pregnancy rates in heifers and cows with cryopreserved sexed sperm: Effects of sperm numbers per inseminate, sorting pressure and sperm storage before sorting  

Microsoft Academic Search

Field trials were conducted to increase fertility with AI of flow-sorted, sexed bovine sperm. In the first trial, a novel competitive fertilization approach was used to compare pressures (30psi vs 50psi) for sorting sperm. Both X- and Y-sperm were sorted to approximately 95% purity at 30 and at 50psi; X-50+Y-30 (and the converse) were mixed in equal numbers for AI

J. L. Schenk; D. G. Cran; R. W. Everett; G. E. Seidel Jr.

2009-01-01

192

Cellular Stretch Increases Superoxide Production in the Thick Ascending Limb  

PubMed Central

Superoxide (O2?) is an important regulator of kidney function. We have recently shown that luminal flow stimulates O2? production in the thick ascending limb (TAL), attributable in part to mechanical factors. Stretch, pressure and shear stress all change when flow increases in the TAL. We hypothesized that stretch rather than shear stress or pressure per se stimulates O2? production by TALs. We measured O2? production in isolated perfused rat TALs using fluorescence microscopy and dihydroethidium. Tubules were perfused with a Na-free solution to eliminate the confounding effect of Na transport. Flow induced an increase in O2? production from 29±4 to 90±8 AU/s (P<0.002; n=5). The response to flow is rapidly reversible. O2? production by TALs perfused at 10 nL/min decreased from 113±6 to 25±10 AU/s (P<0.003; n=4) 15 minutes after flow was stopped. Increasing pressure and stretch in the absence of shear stress caused a significant increase in O2? production (40±6 to 118±17 AU/s; P<0.02; n=5). In contrast, eliminating shear stress had no effect (107±9 versus 108±10 AU/s; n=5). Increasing stretch by 27±2% in the presence of flow while reducing pressure stimulated O2? production from 66±7 to 84±9 AU/s (29±8%; P<0.02; n=5). Tempol inhibited this increase (n=5). We conclude that increasing stretch rather than pressure or shear stress accounts for the mechanical aspect of flow-induced O2? production in the TAL. Stretch of the TAL during hypertension, diabetes, and salt loading may contribute to renal damage.

Garvin, Jeffrey L.; Hong, Nancy J.

2009-01-01

193

Decreasing Epididymal Sperm Reserves Enhances the Detection of Ethoxyethanol-Induced Spermatotoxicity.  

National Technical Information Service (NTIS)

Current test strategies for assessing male reproductive toxicity may be inadequate for estimating risk in humans. High levels of sperm production and existence of large epididymal sperm reserves in most test species may impede the detection of spermatoxic...

M. E. Hurtt H. Zenick

1986-01-01

194

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

195

Sperm binding glycoprotein (SBG) produces calcium and bicarbonate dependent alteration of acrosome morphology and protein tyrosine phosphorylation on boar sperm.  

PubMed

The oviduct is a dynamic organ which modulates gamete physiology. Two subpopulations of sperm have been described in the oviduct of sows, a majority with normal appearance in the deep furrows and a minority, centrally located, and showing damaged membranes. Sperm-oviduct interaction provides the formation of a sperm storage and allows the selection of sperm with certain qualities. Pig (Sus scrofa) oviductal sperm binding glycoprotein (SBG) binds to sperm and exposes Gal beta1-3GalNAc. This disaccharide may be recognized by boar spermadhesin AQN1, which seems to be involved in sperm interaction with the oviduct. SBG is present at the apical surface of the epithelial cells that surround the lumen of the oviduct rather than at the bottom of the crypts. These characteristics imply it could be involved in sperm interaction with this organ. In this study, we evaluate the effect of SBG over boar sperm. We show that the presence of SBG produces alterations of the acrosome morphology of sperm only when they are incubated in capacitating conditions. SBG binds to the periacrosomal region of sperm undergoing capacitation. Its presence induces an increase on the tyrosine-phosphorylation of a polypeptide of apparent molecular mass 97 kDa, as occurs with a 95 kDa protein in other mammalian sperm upon acrosomic reaction. Altogether, these results suggest that SBG might be involved in sperm selection by alteration of the acrosome of sperm that have already begun the capacitation process when they arrive to the oviduct. PMID:17786920

Teijeiro, Juan M; Cabada, Marcelo O; Marini, Patricia E

2008-04-01

196

Peroxisome proliferator-activated receptors increase human sebum production.  

PubMed

Sebum production is key in the pathophysiology of acne, an extremely common condition, which when severe, may require treatment with isotretinoin, a known teratogen. Apart from isotretinoin and hormonal therapy, no agents are available to reduce sebum. Increasing our understanding of the regulation of sebum production is a milestone in identifying alternative therapeutic targets. Studies in sebocytes and human sebaceous glands indicate that agonists of peroxisome proliferator-activated receptors (PPARs) alter sebaceous lipid production. The goal of this study is to verify the expression and activity of PPARs in human skin and SEB-1 sebocytes and to assess the effects of PPAR ligands on sebum production in patients. To investigate the contribution of each receptor subtype to sebum production, lipogenesis assays were performed in SEB-1 sebocytes that were treated with PPAR ligands and isotretinoin. Isotretinoin significantly decreased lipogenesis, while the PPARalpha agonist-GW7647, PPARdelta agonist-GW0742, PPARalpha/delta agonist-GW2433, PPARgamma agonist rosiglitazone, and the pan-agonist-GW4148, increased lipogenesis. Patients treated with thiazolidinediones or fibrates had significant increases in sebum production (37 and 77%, respectively) when compared to age-, disease-, and sex-matched controls. These data indicate that PPARs play a role in regulating sebum production and that selective modulation of their activity may represent a novel therapeutic strategy for the treatment of acne. PMID:16675962

Trivedi, Nishit R; Cong, Zhaoyuan; Nelson, Amanda M; Albert, Adam J; Rosamilia, Lorraine L; Sivarajah, Surendra; Gilliland, Kathryn L; Liu, Wenlei; Mauger, David T; Gabbay, Robert A; Thiboutot, Diane M

2006-09-01

197

Increasing protein production by directed vector backbone evolution  

PubMed Central

Recombinant protein production in prokaryotic and eukaryotic organisms was a key enabling technology for the rapid development of industrial and molecular biotechnology. However, despite all progress the improvement of protein production is an ongoing challenge and of high importance for cost-effective enzyme production. With the epMEGAWHOP mutagenesis protocol for vector backbone optimization we report a novel directed evolution based approach to increase protein production levels by randomly introducing mutations in the vector backbone. In the current study we validate the epMEGAWHOP mutagenesis protocol for three different expression systems. The latter demonstrated the general applicability of the epMEGAWHOP method. Cellulase and lipase production was doubled in one round of directed evolution by random mutagenesis of pET28a(+) and pET22b(+) vector backbones. Protease production using the vector pHY300PLK was increased ~4-times with an average of ~1.25 mutations per kb vector backbone. The epMEGAWHOP does not require any rational understanding of the expression machinery and can generally be applied to enzymes, expression vectors and related hosts. epMEGAWHOP is therefore from our point of view a robust, rapid and straight forward alternative for increasing protein production in general and for biotechnological applications.

2013-01-01

198

Increased Ethylene Production during Clinostat Experiments May Cause Leaf Epinasty  

PubMed Central

Ethylene production from tomato (Lycopersicum esculentum L. cv. Rutgers) plants based on a clinostat doubled during the first 2 hours of rotation. Carbon dioxide blocked the appearance of leaf epinasty normally associated with plants rotated on a clinostat. These results support the idea that epinasty of clinostated plants was due to increased ethylene production and not to the cancellation of the gravitational pull on auxin transport in the petiole. Images

Leather, G. R.; Forrence, L. E.; Abeles, F. B.

1972-01-01

199

Human sperm aneuploidy after exposure to pesticides.  

PubMed

This study examined the effect of paternal environmental exposure to pesticides on the frequency of aneuploidy in human sperm. To determine if the chromosome number in germ cells was altered by paternal exposure, multicolor fluorescence in situ hybridization (FISH) analysis was utilized to measure aneuploidy frequencies in the sperm of 40 men (20 exposed, 20 controls). Samples were coded for "blind analysis" to eliminate scorer bias. Aneuploidy and diploidy frequencies were assessed for chromosomes 13, 21, X, and Y. A minimum of 10,000 sperm was scored per donor per chromosome probe with a total of 809,935 sperm scored. Hybridization efficiency was 99%. There were no significant differences in aneuploidy or diploidy frequencies between exposed and control groups, suggesting that the pesticides did not increase the risk of numerical chromosomal abnormalities in these men. PMID:14735496

Smith, Jena L; Garry, Vincent F; Rademaker, Alfred W; Martin, Renée H

2004-03-01

200

The effects of radiation on sperm swimming behavior depend on plasma oxidative status in the barn swallow ( Hirundo rustica)  

Microsoft Academic Search

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

Andrea Bonisoli-Alquati; Anders Pape Møller; Geir Rudolfsen; Nicola Saino; Manuela Caprioli; Shanna Ostermiller; Timothy A. Mousseau

2011-01-01

201

Sperm selection for ICSI: shape properties do not predict the absence or presence of numerical chromosomal aberrations  

Microsoft Academic Search

BACKGROUND: We hypothesize that the potential relationship between abnormal sperm morphology and increased frequency of numerical chromosomal aberrations is based on two attributes of diminished sperm matu- rity: (i) cytoplasmic retention and consequential sperm shape abnormalities; and (ii) meiotic errors caused by low levels of the HspA2 chaperone, a component of the synaptonemal complex. Because sperm morphology and aneu- ploidies

Ciler Celik-Ozenci; Attila Jakab; Tamas Kovacs; Jillian Catalanotti; Ramazan Demir; Patricia Bray-Ward; David Ward; Gabor Huszar

2004-01-01

202

Insulin affects sperm capacity in pig through nitric oxide.  

PubMed

Insulin (Ins) has recently been demonstrated to have the ability to induce the capacitation process in pig spermatozoa. In various mammalian species, capacitation has been linked to the nitric oxide (NO) signalling; therefore, this study investigated NO production in Ins-treated pig spermatozoa by fluorescence-activated cell sorting. For the same samples, sperm capacitation was evaluated by chlortetracycline staining, protein tyrosine phosphorylation pattern and acrosomal status. A significant increase of the intrasperm NO level and the activation of three capacitation indices were detected in response to Ins treatment. Conversely, sperm preincubation with an NO synthase inhibitor (N-nitro-L-arginine methyl ester) or with the anti-Ins receptor ? (IR?) antibody reversed all of the Ins-related effects. These results suggest that Ins has the capacity to enhance intracellular NO concentrations in pig spermatozoa and indicate a possible NO implication upon Ins promotion of capacitation. PMID:23728590

Aquila, Saveria; Giordano, Francesca; Guido, Carmela; Rago, Vittoria; Carpino, Amalia

2013-11-01

203

Insulin affects sperm capacity in pig through nitric oxide  

PubMed Central

Insulin (Ins) has recently been demonstrated to have the ability to induce the capacitation process in pig spermatozoa. In various mammalian species, capacitation has been linked to the nitric oxide (NO) signalling; therefore, this study investigated NO production in Ins-treated pig spermatozoa by fluorescence-activated cell sorting. For the same samples, sperm capacitation was evaluated by chlortetracycline staining, protein tyrosine phosphorylation pattern and acrosomal status. A significant increase of the intrasperm NO level and the activation of three capacitation indices were detected in response to Ins treatment. Conversely, sperm preincubation with an NO synthase inhibitor (N-nitro-L-arginine methyl ester) or with the anti-Ins receptor ? (IR?) antibody reversed all of the Ins-related effects. These results suggest that Ins has the capacity to enhance intracellular NO concentrations in pig spermatozoa and indicate a possible NO implication upon Ins promotion of capacitation.

Aquila, Saveria; Giordano, Francesca; Guido, Carmela; Rago, Vittoria; Carpino, Amalia

2013-01-01

204

Methods for sperm concentration determination.  

PubMed

Proper assessment of the number of spermatozoa is essential not only as an initial step in every clinical infertility investigation [Björndahl et al (2010) A practical guide to basic laboratory andrology, 1st edn. Cambridge University Press, Cambridge] but also when attempting to establish the total sperm production in the testis [Amann (Hum Reprod 25:22-28, 2010); Amann (J Androl 30:626-641, 2009); Amann and Chapman (J Androl 30:642-649, 2009)]. Reliable methods combined with an understanding of the specific physiology involved as well as the main sources of errors related to the assessment of sperm concentration are critical for ensuring accurate concentration determination [Björndahl et al (2010) A practical guide to basic laboratory andrology, 1st edn. Cambridge University Press, Cambridge; World Health Organization (2010) WHO laboratory manual for the examination and processing of human semen. WHO, Geneva]. This chapter therefore focuses on these three aspects. PMID:22992898

Björndahl, Lars

2013-01-01

205

Real-time automated tracking and trapping system for sperm.  

PubMed

We have developed a microscope system for real-time single sperm tracking with an automated laser tweezers escape power assay. Phase contrast images of swimming sperm are digitized to the computer at video rate. The custom algorithm creates a region of interest centered about a sperm in response to a mouse click and performs all subsequent tasks autonomously. Microscope stage movement responds to feedback from video analysis of swimming sperm to center the sperm with respect to the field of view. For escape power assays, sperm are automatically relocated to the laser trap focus where they are held for a user-defined duration at fixed power, or held as laser power is gradually reduced. The sperm's position is automatically monitored to measure the laser power at which the sperm escapes the trap. Sperm are tracked for extended durations before and after laser trap experiments. Motility measurements including the curvilinear velocity and the absolute position of the sperm relative to the cell chamber are calculated and written to the hard drive at video rate. Experimental throughput is increased over 30 times compared to off-line data analysis. The efficacy of the "track and trap" algorithm is validated through examples and comparisons with the manually collected data. PMID:16892192

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

2006-11-01

206

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.

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

2013-01-01

207

A sperm-activating peptide controls a cGMP-signaling pathway in starfish sperm.  

PubMed

Peptides released from eggs of marine invertebrates play a central role in fertilization. About 80 different peptides from various phyla have been isolated, however, with one exception, their respective receptors on the sperm surface have not been unequivocally identified and the pertinent signaling pathways remain ill defined. Using rapid mixing techniques and novel membrane-permeable caged compounds of cyclic nucleotides, we show that the sperm-activating peptide asterosap evokes a fast and transient increase of the cGMP concentration in sperm of the starfish Asterias amurensis, followed by a transient cGMP-stimulated increase in the Ca(2+) concentration. In contrast, cAMP levels did not change significantly and the Ca(2+) response evoked by photolysis of caged cAMP was significantly smaller than that using caged cGMP. By cloning of cDNA and chemical crosslinking, we identified a receptor-type guanylyl cyclase in the sperm flagellum as the asterosap-binding protein. Sperm respond exquisitely sensitive to picomolar concentrations of asterosap, suggesting that the peptide serves a chemosensory function like resact, a peptide involved in chemotaxis of sperm of the sea urchin Arbacia punctulata. A unifying principle emerges that chemosensory transduction in sperm of marine invertebrates uses cGMP as the primary messenger, although there may be variations in the detail. PMID:12921734

Matsumoto, Midori; Solzin, Johannes; Helbig, Annika; Hagen, Volker; Ueno, Sei-ichi; Kawase, Osamu; Maruyama, Yoshinori; Ogiso, Manabu; Godde, Matthias; Minakata, Hiroyuki; Kaupp, U Benjamin; Hoshi, Motonori; Weyand, Ingo

2003-08-15

208

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

2014-06-01

209

The Increasing Dominance of Teams in Production of Knowledge  

NSDL National Science Digital Library

This article explores published literature to demonstrate the dominance of teams over solo authors in the production of knowledge.Teams of two or more people are increasingly producing more of the research, and the research they generate is more highly cited, in a wide variety of endeavors from science to the arts.

Wuchty, Stefan

2009-01-26

210

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...

211

Future seagrass beds: can increased productivity lead to increased carbon storage?  

PubMed

While carbon capture and storage (CCS) is increasingly recognised as technologically possible, recent evidence from deep-sea CCS activities suggests that leakage from reservoirs may result in highly CO2 impacted biological communities. In contrast, shallow marine waters have higher primary productivity which may partially mitigate this leakage. We used natural CO2 seeps in shallow marine waters to assess if increased benthic primary productivity could capture and store CO2 leakage in areas targeted for CCS. We found that the productivity of seagrass communities (in situ, using natural CO2 seeps) and two individual species (ex situ, Cymodocea serrulata and Halophila ovalis) increased with CO2 concentration, but only species with dense belowground biomass increased in abundance (e.g. C. serrulata). Importantly, the ratio of below:above ground biomass of seagrass communities increased fivefold, making seagrass good candidates to partially mitigate CO2 leakage from sub-seabed reservoirs, since they form carbon sinks that can be buried for millennia. PMID:23453889

Russell, Bayden D; Connell, Sean D; Uthicke, Sven; Muehllehner, Nancy; Fabricius, Katharina E; Hall-Spencer, Jason M

2013-08-30

212

ACROSOMAL DISRUPTION IN SPERM  

PubMed Central

"Capacitation" is a physiological event which alters sperm to permit rapid penetration through oocyte investments and fusion between gametes. Acrosomal "reaction," the physiological release of acrosomal contents, occurs after this facilitating process. In this study, acrosomal "disruption" of guinea pig and rat sperm was achieved in vitro by incubating sperm together with the follicular contents of superovulated mice. The samples contained both "reacted" and "disrupted" sperm. Thin sections of affected sperm revealed rupture and vesiculation of the plasma membrane overlying the acrosome, as well as loss of both the outer acrosomal membrane and the acrosomal content. Freeze-fracture revealed disintegration of the characteristic geometric patterns in regions of the acrosomal and plasma membranes thus disrupted and major modifications in particle distribution in the sperm tail. In the guinea pig, strands of 6–8-nm particles, usually confined to the plasma membrane of the midpiece, which overlies mitochondria, also appeared in the principal piece. Likewise, in rat sperm, bands of similarly small particles formed acute angles throughout the membrane of the principal piece. Compared with the membranes of control preparations, these membrane alterations are apparently a direct consequence of incubation with ovarian follicular contents.

Friend, Daniel S.; Rudolf, Irene

1974-01-01

213

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

214

New assays for detection and localization of endogenous lipid peroxidation products in living boar sperm after BTS dilution or after freeze–thawing  

Microsoft Academic Search

Reactive oxygen species have been implicated in sperm aberrations causing multiple pathologies including sub- and infertility. Freeze\\/thawing of sperm samples is routinely performed in the cattle breeding industries for semen storage prior to artificial insemination but unusual in porcine breeding industries as semen dilution and storage at 17?C is sufficient for artificial insemination within 2–3 days. However, longer semen storage

Jos F. Brouwers; Patricia F. N. Silva; Barend M. Gadella

2005-01-01

215

Imidacloprid increases egg production in Amblyseius victoriensis (Acari: Phytoseiidae)  

Microsoft Academic Search

The chloronicotinyl insecticide, imidacloprid, recommended for aphid control in Australian stone fruit orchards, was examined\\u000a for its impact on survival and egg production in Amblyseius victoriensis Womersley. Imidacloprid at the field rate (0.0053%\\u000a a.i.) was non-toxic, but repellent to A. victoriensis in laboratory bioassays. Females treated with imidacloprid showed increased\\u000a egg production, producing 1.9–2.0 eggs per day compared with 1.3–1.6

David G. James

1997-01-01

216

In vitro fertilization using non-sexed and sexed bovine sperm: sperm concentration, sorter pressure, and bull effects.  

PubMed

The objective of these experiments was to study bovine in vitro fertilization (IVF) conditions for blastocyst production using non-sexed sperm (Experiment 1) and sexed sperm (Experiment 2). For Experiment 1, in vitro-matured oocytes (N=707) were allocated to a 2 × 3 × 4 factorial design: time of co-incubation of gametes for fertilization (4 and 18 h), sperm dose (1, 0.33, and 0.11 × 10(6) frozen-thawed sperm/ml, and sperm source (four bulls). Pronuclear status was evaluated for a subset. Experiment 2 (N=2155 oocytes) was a 2 × 3 × 2 × 6 factorial design: sex of sperm (X and Y), sperm dose (1, 0.33, and 0.11 × 10(6) frozen-thawed sperm/ml), and sperm-sorting pressures (40 and 50 psi), replicated with sperm of six bulls. Presumptive zygotes were cultured 60 h in chemically defined medium-1 (CDM-1), and for 114 h in CDM-2. For Experiment 1, pronuclear formation, cleavage and blastocysts rates were greater for 1, and 0.33 × 10(6) than 0.11 × 10(6) sperm/ml (72 and 62 vs 42%; 89 and 81 vs 58%; and 21 and 17 vs 9%, respectively; all p<0.01); polyspermy was greater for 1, than 0.33 and 0.11 × 10(6) sperm concentrations (24 vs 2 and 0%; p<0.01). There were greater main effects (p<0.01) of pronuclear formation (69 vs 48%), polyspermy (13 vs 4%), and cleavage (63 vs 54%), at 18 than at 4 h of co-incubation of gametes (all p<0.01). For Experiment 2, cleavage and blastocyst rates were greater for 1 × 10(6) sperm/ml vs 0.33 and 0.11 (69%, 47%, and 30% cleavage and 30%, 14%, and 8% blastocysts) and 40 vs 50 psi (54% and 44% cleavage and 18% and 15% blastocysts) (p<0.01). A marked bull by fertilization sperm dose interaction was found for cleavage (p<0.05). The main conclusion was that the optimal sperm concentration for cleavage and producing blastocysts via IVF with sexed sperm was considerably higher and more variable among bulls than for unsexed sperm. PMID:20946538

Barceló-Fimbres, M; Campos-Chillón, L F; Seidel, G E

2011-06-01

217

Human sperm tail proteome suggests new endogenous metabolic pathways.  

PubMed

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

2013-02-01

218

Effect of oxamic analogues on functional mice sperm parameters.  

PubMed

Abstract 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 IC50 values for hexokinase and glyceraldehyde-3-phosphate dehydrogenase were at least an order of magnitude greater than LDH-C4 IC50 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

219

Efficacy of sperm mobility assessment in commercial flocks and the relationships of sperm mobility and insemination dose with fertility in turkeys.  

PubMed

Our objectives were to evaluate: 1) the efficacy of the Sperm Mobility Test on commercial turkey farms, and 2) the influence of sperm mobility phenotype on fertility when insemination parameters are varied. In research flocks, differences in sperm mobility among toms are predictive of fertility. We wanted to test the efficacy of this sire selection test in practical, real-world situations, evaluating its usefulness in terms of assessing large numbers of toms, different strains of turkeys, and variable management practices. Utilizing field study results, controlled studies were then conducted to improve test parameters. For the field trials, semen from each of 405 breeder toms (11 strains or lines) was evaluated either in duplicate (n = 285) or in triplicate (n = 120). Sperm mobility was normally distributed among all toms tested, except for one strain. Because the sperm mobility indices for toms evaluated in these field trials were higher than those observed in research flocks, the Sperm Mobility Test was modified to increase the separation between high and low sperm mobility phenotypes by increasing the concentration of Accudenz. To determine the effects of sperm mobility and insemination dose on sustained fertility through time, hens from a research flock were inseminated twice before the onset of lay with sperm from toms classified as high-, average-, or low-mobility in concentrations of 25 to 400 million sperm per artificial insemination dose, and egg fertility was evaluated over a 5-wk period. Toms with the high-mobility sperm phenotype maintained higher fertility (P < 0.05) over the 5-wk period at all insemination doses compared with toms with low-mobility sperm. Toms with high-mobility sperm sired equal numbers of poults in a sperm competition study in which numbers favored low-mobility toms by 3:1. These results demonstrate that the Sperm Mobility Test can be used for on-farm evaluation of semen quality of toms in commercial flocks and that sperm mobility influences fertility and sire fitness. PMID:11194043

King, L M; Kirby, J D; Froman, D P; Sonstegard, T S; Harry, D E; Darden, J R; Marini, P J; Walker, R M; Rhoads, M L; Donoghue, A M

2000-12-01

220

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

221

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

222

Methods of increasing hydrocarbon production from subterranean formations  

SciTech Connect

A method is described of increasing the production of hydrocarbons from a hydrocarbon-containing subterranean carbonate-containing formation comprising introducing into the subterranean formation an anionic perfluoro substituted compound in a liquid carrier fluid whereby the compound is absorbed onto surfaces of the formation to reduce wetting of the surfaces by either hydrocarbons or water, the anionic perfluoro substituted compound being selected from individual compounds and mixtures thereof.

Penny, G.S.; Gardner, T.R.

1986-04-29

223

Intracytoplasmic sperm injection by testicular sperm in patients with aspermia or azoospermia after cancer treatment.  

PubMed

The aim of this retrospective study was to evaluate the efficiency of testicular biopsy and intracytoplasmic sperm injection (ICSI) in patients with aspermia or non-obstructive azoospermia (NOA) after cancer treatment. From 1996 to 2003, 30 men with a history of cancer, affected by aspermia or NOA and without sperm cryopreserved before cytotoxic treatment underwent testicular sperm extraction (TESE). In these men, clinical, hormonal and histological characteristics were compared; 13 underwent 39 TESE-ICSI cycles using frozen-thawed testicular spermatozoa (TESE-ICSI group). In the same period, 31 ICSI cycles were performed in 20 men with aspermia or NOA using ejaculated sperm frozen before cancer treatment (ejaculated sperm-ICSI group). Fertilization, blastocyst development, pregnancy and miscarriage rates were compared between the groups. Testicular volume, serum follicle-stimulating hormone level and Johnsen score indicated complete although reduced spermatogenesis in men with aspermia and abnormal spermatogenesis in men with NOA. After TESE, sperm retrieval was positive in 92% of men with aspermia and 58% of men with NOA. In TESE-ICSI patients with NOA a significantly lower proportion of embryos developed to the blastocyst stage than in patients with aspermia and in those after ICSI with frozen-thawed ejaculated sperm (23% vs. 43% and 47%, p = 0.03 and p < 0.01 respectively). In all groups the miscarriage rates were high; in patients with aspermia and NOA, characterized by increased age, the miscarriage rate tended to be higher in spite of similar female age and female indications of infertility. In patients affected by aspermia or NOA after cancer treatment and without sperm cryopreserved before treatment, TESE-ICSI using testicular sperm provide a chance to father a child. PMID:16524365

Zorn, B; Virant-Klun, I; Stanovnik, M; Drobnic, S; Meden-Vrtovec, H

2006-10-01

224

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

225

Zymomonas mobilis mutants with an increased rate of alcohol production  

SciTech Connect

Two new derivatives of Zymomonas mobilis CP4 were isolated from enrichment cultures after 18 months of serial transfer. These new strains were selected for the ability to grow and produce ethanol rapidly on transfer into fresh broth containing ethanol and allyl alcohol. Ethanol production by these strains was examined in batch fermentations under three sets of conditions. Both new derivatives were found to be superior to the parent strain CP4 with respect to the speed and completeness of glucose conversion to ethanol. The best of these, strain YO2, produced 9.5% ethanol (by weight; 11.9% by volume) after 17.4 h compared with 31.8 h for the parent strain CP4. The addition of 1 mM magnesium sulfate improved ethanol production in all three strains. Two factors contributed to the decrease in fermentation time required by the mutants: more rapid growth with minimal lag on subculturing and the retention of higher rates of ethanol production as fermentation proceeded. Alcohol dehydrogenase isozymes were altered in both new strains and no longer catalyzed the oxidation of allyl alcohol into the toxic product acrolein. This loss of allyl alcohol-oxidizing capacity is proposed as a primary factor contributing to increased allyl alcohol resistance, although it is likely that other mutations affecting glycolysis also contribute to the improvement in ethanol production.

Osman, Y.A.; Ingram, L.O.

1987-07-01

226

Zymomonas mobilis Mutants with an Increased Rate of Alcohol Production  

PubMed Central

Two new derivatives of Zymomonas mobilis CP4 were isolated from enrichment cultures after 18 months of serial transfers. These new strains were selected for the ability to grow and produce ethanol rapidly on transfer into fresh broth containing ethanol and allyl alcohol. Ethanol production by these strains was examined in batch fermentations under three sets of conditions. Both new derivatives were found to be superior to the parent strain CP4 with respect to the speed and completeness of glucose conversion to ethanol. The best of these, strain YO2, produced 9.5% ethanol (by weight; 11.9% by volume) after 17.4 h compared with 31.8 h for the parent strain CP4. The addition of 1 mM magnesium sulfate improved ethanol production in all three strains. Two factors contributed to the decrease in fermentation time required by the mutants: more rapid growth with minimal lag on subculturing and the retention of higher rates of ethanol production as fermentation proceeded. Alcohol dehydrogenase isozymes were altered in both new strains and no longer catalyzed the oxidation of allyl alcohol into the toxic product acrolein. This loss of allyl alcohol-oxidizing capacity is proposed as a primary factor contributing to increased allyl alcohol resistance, although it is likely that other mutations affecting glycolysis also contribute to the improvement in ethanol production. Images

Osman, Y. A.; Ingram, L. O.

1987-01-01

227

Sperm from pheromone primed brown trout (Salmo trutta L.) produce more larvae.  

PubMed

Male goldfish (Carassius auratus) exposed to female hormonal pheromones express increased milt volumes and their sperm fertilize more eggs than sperm from unprimed males. Ovulated salmonid females also release odours that increase volumes of strippable milt in males. It is, however, not known if the priming pheromones affect the ability of sperm to fertilize eggs in salmonids. In this study, we compare the proportion of larvae produced from in vitro fertilization tests between primed brown trout (Salmo trutta) males exposed to a mix of female urine and ovarian fluids, and control males exposed only to 0.9 % sodium chloride. We also investigate priming effects on milt yield and sperm motility. Fertilization tests with sperm from single males, as well as sperm from two males (i.e., sperm competition), were performed. Primed males generated more larvae in both the single male and competition fertilization tests. No differences between treatments in milt yield and sperm motility could be established. PMID:22976196

Hellström, Gustav; Prestegaard, Tore; Dannewitz, Johan; Olsén, K Håkan

2013-06-01

228

An efficient method of guinea fowl sperm cryopreservation.  

PubMed

France is the only country that practices pedigree selection of guinea fowl for meat production. The increasing risk of line extinction for sanitary or breeding failure reasons makes clear the need for an efficient method of reproductive cell cryopreservation in this species. However, an efficient method of guinea fowl sperm freezing in secured packaging is still lacking. The aim of the present study was to develop such a method. Based on results previously obtained in chickens, different cryoprotectants and freezing/thawing processes were tested and then adapted to guinea fowl. Semen quality was measured by semen viability evaluation and then by fertility measured after intravaginal artificial insemination. The best results (70% fertility with frozen-thawed sperm) were obtained by the use of the permeant cryoprotectant agents dimethyl formamide combined with a freezing rate of 30°C/min. The initial insemination frequency also affected the fertility results: 2 consecutive days of inseminations were needed in the first week to ensure enough filling of the utero-vaginal glands of the guinea fowl hen and thus to get successive fertile eggs. Thereafter, a 2-wk insemination frequency was sufficient. This new method, combining biophysical (cryoprotectant agents, freeze/thaw rate) and zootechnical (artificial insemination frequency) features, is the first cryopreservation method successfully developed in secured packaging for guinea fowl sperm. This method is now available for the practice of gene bank conservation and male reproductive management. PMID:24135603

Seigneurin, F; Grasseau, I; Chapuis, H; Blesbois, E

2013-11-01

229

Male mating behavior and ejaculate expenditure under sperm competition risk in the eastern mosquitofish  

Microsoft Academic Search

Theory predicts that males should tailor the size of their ejaculates according to temporal changes in the risk of sperm competition. Specifically, males are predicted to allocate more sperm to each mating event with increasing risk (i.e., the probability that the sperm from two males will compete for fertilization). We tested this hypothesis by using the eastern mosquitofish, a freshwater

Jonathan P. Evans; Michele Pierotti; Andrea Pilastro

2003-01-01

230

Sperm quality as reflected through morphology in salmon alternative life histories.  

PubMed

Male salmon exhibit alternative mating strategies, as both older anadromous adults and precocious juveniles (parr) participate in the spawning of a single female. This study tested the following hypotheses: 1) different intensities of sperm competition may reflect different sperm tail optima; 2) long spermatozoa are superior to short ones, with an associated cost on sperm longevity; and 3) a disfavored role in sperm competition selects for parr investing more in sperm quality. Comparisons included sperm morphological traits, whereas sperm quality was investigated by motility duration observations, measurement of the sperm adenylate system, and fertilization experiments. No evidence of different adaptive sperm dimensions between the male types was found. Positive association between spermatocrit and energy charge was, however, detected. Sperm length parameters correlated positively with ATP, energy charge, and fertilization success, whereas no evidence for an effect of sperm morphology on longevity was found. Male parr had greater spermatocrit than adults and fertilized equal proportions of eggs as adults despite a pronounced numerical subordinance in the fertilization experiments. It is concluded that a long sperm tail and midpiece may be selected to optimize energetic demands under conditions of increased sperm competition intensity. PMID:11751270

Vladi?, Tomislav V; Afzelius, Björn A; Bronnikov, Gennady E

2002-01-01

231

PTX3 Stimulates Osteoclastogenesis by Increasing Osteoblast RANKL Production.  

PubMed

Pentraxin-3 (PTX3), also known as tumor necrosis factor-stimulated gene 14 (TSG-14), is produced by immune and vascular cells in response to pro-inflammatory signals and is therefore a multipotent inflammatory mediator. The present study showed that during human osteoblast (OB) differentiation, precursor OBs (pOBs), but not mature OB, highly expressed PTX3. TNF? treatment elevated the PTX3 expression of pOBs. When mice were injected with lipopolysaccharide, which induces an inflammatory osteolytic condition characterized by trabecular bone destruction and high osteoclastogenesis, their bone marrow cells expressed elevated levels of PTX3 protein. Exogenous PTX3 did not directly affect osteoclast (OC) or OB differentiation. However, when pOBs and precursor OCs were co-cultured, exogenous PTX3 significantly increased the number of tartrate-resistant acid phosphatase-positive multinucleated cells (i.e., OC cells) by increasing the pOB mRNA expression and protein secretion of RANK ligand (RANKL). This was accompanied with increased Runt-related transcription factor 2 (Runx2) expression in the pOBs. Knock-down of endogenous PTX3 with small-interfering RNA did not change the osteogenic potential of pOBs but suppressed their production of RANKL and reduced osteoclastogenesis. Finally, TNF? treatment of the co-culture elevated PTX3 expression by the pOBs and increased OC formation. This effect was suppressed by PTX3 knock-down by decreasing RANKL expression. Thus, the PTX3-driven increase in the osteoclastogenic potential of pOBs appears to be mediated by the effect of PTX3 on pOB RANKL production. These findings suggest that PTX3 is an inflammatory mediator that contributes to the deteriorating osteolytic condition of inflamed bone. J. Cell. Physiol. 229: 1744-1752, 2014. © 2014 Wiley Periodicals, Inc. PMID:24664887

Lee, Eun-Jin; Song, Da-Hyun; Kim, Yeon-Ju; Choi, Bongkun; Chung, Yeon-Ho; Kim, Sang-Min; Koh, Jung-Min; Yoon, Seung-Yong; Song, Youngsup; Kang, Sang-Wook; Chang, Eun-Ju

2014-11-01

232

Improvement of Stand Jig Sealer and Its Increased Production Capacity  

NASA Astrophysics Data System (ADS)

This paper has the objective to prove that improvement of Stand Jig Sealer can lead to the cycle time target as part of Improvement efforts and its Productivity. Prior researches through prior journals both classics journal such as Quesnay (1766) and Solow (1957) and updated journal such as Reikard (2011) researches, are mentioned and elaborated. Precisely, the research is narrowed down and specified into automotive industry and eventually the software related of SPSS and Structural Equation Modeling ( SEM ). The analysis and its method are conducted through the calculation working time. The mentioned calculation are reinforced with the hypothesis test using SPSS Version 19 and involve parameters of production efficiency, productivity calculation, and the calculation of financial investments. The results obtained are augmented achievement of cycle time target ? 80 seconds posterior to improvement stand jig sealer. The result from calculation of SPSS-19 version comprise the following aspects: the one-sided hypothesis test is rejection of Ho:??80 seconds, the correlation rs=0.84, regression y = 0.159+0.642x, validity R table = 0.4438, reliability value of Cronbach's alpha = 0.885>0.70, independence (Chi Square) Asymp. Sig=0.028<0.05, 95% efficiency, increase productivity 11%, financial analysis (NPV 2,340,596>0, PI 2.04>1, IRR 45.56%>i=12.68%, PP=1.86). The Mentioned calculation results support the hypothesis and ultimately align with the objective of this paper to prove that improvement of Stand Jig Sealer and its relation toward the cycle time target. Precisely, the improvement of production capacity of PT. Astra Daihatsu Motor.

Soebandrija, K. E. N.; Astuti, S. W. D.

2014-03-01

233

Method of increasing hydrocarbon production by remedial well treatment  

SciTech Connect

This patent describes a method for increasing the production of hydrocarbons from a hydrocarbon-containing subterranean formation having impaired permeability as a result of formation invasion by aqueous fluids comprising contacting the formation with a penetrating solvent capable of disrupting at least a portion of any aqueous layer present on solid surfaces within the formation and a cationic perfluoro compound whereby the compound is absorbed onto the solid surfaces of the formation the cationic perfluoro compound being selected from the group consisting of a compound or mixtures of compounds.

Penny, G.S.; Briscoe, J.E.

1986-01-21

234

Mass spectrometric detection of cholesterol oxidation in bovine sperm.  

PubMed

We report on the presence and formation of cholesterol oxidation products (oxysterols) in bovine sperm. Although cholesterol is the most abundant molecule in the membrane of mammalian cells and is easily oxidized, this is the first report on cholesterol oxidation in sperm membranes as investigated by state-of-the-art liquid chromatographic and mass spectrometric methods. First, oxysterols are already present in fresh semen samples, showing that lipid peroxidation is part of normal sperm physiology. After chromatographic separation (by high-performance liquid chromatography), the detected oxysterol species were identified with atmospheric pressure chemical ionization mass spectrometry in multiple-reaction-monitoring mode that enabled detection in a broad and linear concentration range (0.05-100 pmol for each oxysterol species detected). Second, exposure of living sperm cells to oxidative stress does not result in the same level and composition of oxysterol species compared with oxidative stress imposed on reconstituted vesicles from protein-free sperm lipid extracts. This suggests that living sperm cells protect themselves against elevated oxysterol formation. Third, sperm capacitation induces the formation of oxysterols, and these formed oxysterols are almost completely depleted from the sperm surface by albumin. Fourth, and most importantly, capacitation after freezing/thawing of sperm fails to induce both the formation of oxysterols and the subsequent albumin-dependent depletion of oxysterols from the sperm surface. The possible physiological relevance of capacitation-dependent oxysterol formation and depletion at the sperm surface as well as the omission of this after freezing/thawing semen is discussed. PMID:21415139

Brouwers, Jos F; Boerke, Arjan; Silva, Patrícia F N; Garcia-Gil, Nuria; van Gestel, Renske A; Helms, J Bernd; van de Lest, Chris H A; Gadella, Bart M

2011-07-01

235

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...

236

New system for long-term monitoring of sperm motility: EDTA effect on semen.  

PubMed

Many drugs act as sperm stimulants and are of clinical value for male infertility. Current research deals with the physiological mechanisms of sperm motility/sperm stimulation and how long the effect lasts. For such a study, long-term monitoring of sperm motility becomes essential for traditional semen evaluation. A new system was designed to deal with the microscopic images of semen. Its performance was evaluated by studying the effect of EDTA on sperm motility. EDTA increased sperm curvilinear velocity (Vcl) and straight-line velocity (Vsl) by 31 and 20%. EDTA also prolonged the duration of motility by 68 and 61%, respectively. However, EDTA had less effect on the linearity of forward progression (Lin). The proposed system can analyze semen and does well at monitoring sperm motility for short term and long term. It may be valuable to test the possible role of sperm stimulation for male infertility and assisted reproduction. PMID:9730441

Kuo, Y L; Tzeng, W L; Chiang, H K; Ni, R F; Lee, T C; Young, S T

1998-01-01

237

Effects of centrifugation before freezing on boar sperm cryosurvival.  

PubMed

Current protocols for boar sperm cryopreservation require the centrifugation of semen in order to separate sperm cells from the seminal plasma. This study evaluated the influence of different centrifugation regimes on both sperm recovery and yield (percentage of viable sperm with an intact acrosome relative to the initial sperm population) after centrifugation (experiment 1) as well as the influence of different centrifugation regimes on boar sperm cryosurvival (experiment 2). In both experiments, sperm-rich fractions from 3 boars were diluted, pooled, and cooled to 17 degrees C before centrifugation. In experiment 1, the g-forces tested were 400, 800, 1600, and 2400 x g for 3 or 5 minutes, using the standard regime (800 x g for 10 minutes) as a reference. Sperm recovery (Bürker Chamber) and yield (triple fluorescent stain of PI/R123/FITC-PNA [DNA-specific fluorochrome propidium iodide/mitochondria-specific fluorochrome rhodamine-123/acrosome-specific fluorochrome fluorescein isothiocyanate-labeled peanut (Arachis hypogaea) agglutinin]) were calculated. The highest recovery and yield (P <.05) values were achieved using 2400 x g for 5 or 3 minutes and 1600 x g for 5 minutes, which showed no differences (P >.05) from the reference in terms of sperm yield. In experiment 2, cooled semen was centrifuged using 3 different regimes: C1 (2400 x g for 3 minutes), C2 (1600 x g for 5 minutes), and C3 (800 x g for 10 minutes). Pellets were diluted in lactose-egg yolk (LEY)-glycerol-Equex STM (1 x 10(9) cells/mL) and frozen in 0.5-mL straws. After thawing, sperm quality was assessed after 30 and 150 minutes of incubation (37 degrees C). Centrifugation regimes C1 and C2 showed significantly (P <.05) higher postthaw sperm motility (assessed with a computer-assisted semen analysis system), viability (evaluated as for experiment 1), and percentage of uncapacitated sperm (assessed with a chlortetracycline assay) than did C3. In addition, C1 had the highest (P <.05) oocyte penetrating ability (assessed with the homologous in vitro penetration test performed with immature oocytes). Malondialdehyde production, assessed with the thiobarbituric acid reactive species test, was unaffected (P >.05) by the centrifugation regime used. We conclude that high g-force (2400 x g) and short centrifugation time (3 minutes) do not affect sperm recovery and yield and that, moreover, they have a positive effect on the cryosurvival of boar sperm. Therefore, we recommend the use of short-term centrifugation with a relatively high g-force (2400 x g for 3 minutes) in boar sperm cryopreservation protocol. PMID:15064317

Carvajal, Gema; Cuello, Cristina; Ruiz, Maria; Vázquez, Juan María; Martínez, Emilio Arsenio; Roca, Jordi

2004-01-01

238

Analysis of sperm chromosome complements before, during, and after chemotherapy.  

PubMed

Sperm chromosomal abnormalities were assessed in testicular cancer patients before, during, and after BEP (bleomycin, etoposide, cisplatin) chemotherapy (CT). Multicolor fluorescence in situ hybridization (FISH) analysis was employed to detect aneuploidy for chromosomes 1, 12, X, and Y, and diploidy. Sperm samples were cryopreserved and coded before analysis to facilitate "blind" analysis. Complete results at all time points was available for only one patient. A total of 60,400 sperm were analyzed: 20,004 before CT, 20,005 during CT, and 20,391 after CT. There was a significant increase in the frequency of 24,XY sperm during (0.33%) and post-CT (0.34%) compared to pre-CT (0.14%). This study suggests that there may be a significantly increased risk of chromosomal abnormalities in sperm of CT patients during and immediately post-CT, similar to that shown in animal models. PMID:9973940

Martin, R H; Ernst, S; Rademaker, A; Barclay, L; Ko, E; Summers, N

1999-01-15

239

Mobilisation of Ca2+ stores and flagellar regulation in human sperm by S-nitrosylation: a role for NO synthesised in the female tract  

PubMed Central

Summary Generation of NO by nitric oxide synthase (NOS) is implicated in gamete interaction and fertilisation. Exposure of human spermatozoa to NO donors caused mobilisation of stored Ca2+ by a mechanism that did not require activation of guanylate cyclase but was mimicked by S-nitroso-glutathione (GSNO; an S-nitrosylating agent). Application of dithiothreitol, to reduce protein –SNO groups, rapidly reversed the actions of NO and GSNO on [Ca2+]i. The effects of NO, GSNO and dithiothreitol on sperm protein S-nitrosylation, assessed using the biotin switch method, closely paralleled their actions on [Ca2+]i. Immunofluorescent staining revealed constitutive and inducible NOS in human oviduct and cumulus (the cellular layer investing the oocyte). 4,5-diaminofluorescein (DAF) staining demonstrated production of NO by these tissues. Incubation of human sperm with oviduct explants induced sperm protein S-nitrosylation resembling that induced by NO donors and GSNO. Progesterone (a product of cumulus cells) also mobilises stored Ca2+ in human sperm. Pre-treatment of sperm with NO greatly enhanced the effect of progesterone on [Ca2+]i, resulting in a prolonged increase in flagellar excursion. We conclude that NO regulates mobilisation of stored Ca2+ in human sperm by protein S-nitrosylation, that this action is synergistic with progesterone and that this synergism is potentially highly significant in gamete interactions leading to fertilisation.

Machado-Oliveira, Gisela; Lefievre, Linda; Ford, Christopher; Herrero, M Belen; Barratt, Christopher; Connolly, Thomas J; Nash, Katherine; Morales-Garcia, Aduen; Kirkman-Brown, Jackson; Publicover, Steve

2009-01-01

240

Total productive maintenance and change over reduction engineering a way to increase quality and productivity  

Microsoft Academic Search

Summary form only given. Total productive maintenance (TPM) and change over reduction engineering (CORE) are fundamental parts of the just-in-time production system and a way to increase productivity and quality. The major TPM improvement activities include maximizing equipment effectiveness, eliminating the six big equipment-related losses, autonomous maintenance by operators and small group activities, training to improve operation and maintenance skills

S. Schmidt

1997-01-01

241

The ecological and evolutionary consequences of sperm chemoattraction.  

PubMed

Chemical communication between sperm and egg is a critical factor mediating sexual reproduction. Sperm attractants may be significant evolutionarily for maintaining species barriers, and important ecologically for increasing gamete encounters. Still unresolved, however, are the functional consequences of these dissolved signal molecules. Here, we provide experimental evidence that sperm chemoattraction directly affects the magnitude of fertilization success. The recent discovery of L-tryptophan as a potent attractant to red abalone (Haliotis rufescens) sperm affords the opportunity to quantify how navigation affects gamete interactions. Sperm behavioral responses to manipulations of the natural tryptophan gradient around individual eggs reveals that both chemotaxis and chemokinesis significantly promote contacts. Our results show further that attractant release by means of diffusion effectively doubles the target size of red abalone eggs, which in turn significantly increases fertilization success. Although long theorized as potential barriers to hybridization, species-specific sperm attractants in red and green (Haliotis fulgens) abalone are only minor contributors to maintaining reproductive isolation. Because abalone typically live in dense, multispecies aggregations, chemically mediated navigation would prevent sperm from pointlessly tracking heterospecific eggs. Thus, even though reproductive isolation fundamentally resides at the level of membrane recognition proteins, species-specific sperm attractants may evolve to locate the right target within mixed gamete suspensions of closely related species. PMID:15070747

Riffell, Jeffrey A; Krug, Patrick J; Zimmer, Richard K

2004-03-30

242

Effects of viscosity on sperm motility studied with optical tweezers.  

PubMed

The purpose of this study is to analyze human sperm motility and energetics in media with different viscosities. Multiple experiments were performed to collect motility parameters using customized computer tracking software that measures the curvilinear velocity (VCL) and the minimum laser power (Pesc) necessary to hold an individual sperm in an optical trap. The Pesc was measured by using a 1064 nm Nd:YVO(4) continuous wave laser that optically traps motile sperm at a power of 450 mW in the focused trap spot. The VCL was measured frame by frame before trapping. In order to study sperm energetics under different viscous conditions sperm were labeled with the fluorescent dye DiOC(6)(3) to measure membrane potentials of mitochondria in the sperm midpiece. Fluorescence intensity was measured before and during trapping. The results demonstrate a decrease in VCL but an increase in Pesc with increasing viscosity. Fluorescent intensity is the same regardless of the viscosity level indicating no change in sperm energetics. The results suggest that, under the conditions tested, viscosity physically affects the mechanical properties of sperm motility rather than the chemical pathways associated with energetics. PMID:22463031

Hyun, Nicholas; Chandsawangbhuwana, Charlie; Zhu, Qingyuan; Shi, Linda Z; Yang-Wong, Collin; Berns, Michael W

2012-02-01

243

Comprehensive mapping of the bull sperm surface proteome.  

PubMed

While the mechanisms that underpin maturation, capacitation, and sperm-egg interactions remain elusive it is known that these essential fertilisation events are driven by the protein complement of the sperm surface. Understanding these processes is critical to the regulation of animal reproduction, but few studies have attempted to define the full repertoire of sperm surface proteins in animals of agricultural importance. Recent developments in proteomics technologies, subcellular fractionation, and optimised solubilisation strategies have enhanced the potential for the comprehensive characterisation of the sperm surface proteome. Here we report the identification of 419 proteins from a mature bull sperm plasma membrane fraction. Protein domain enrichment analyses indicate that 67% of all the proteins identified may be membrane associated. A large number of the proteins identified are conserved between mammalian species and are reported to play key roles in sperm-egg communication, capacitation and fertility. The major functional pathways identified were related to protein catabolism (26S proteasome complex), chaperonin-containing TCP-1 (CCT) complex and fundamental metabolic processes such as glycolysis and energy production. We have also identified 118 predicted transmembrane proteins, some of which are implicated in cell adhesion, acrosomal exocytosis, vesicle transport and immunity and fertilisation events, while others have not been reported in mammalian LC-MS-derived sperm proteomes to date. Comparative proteomics and functional network analyses of these proteins expand our system's level of understanding of the bull sperm proteome and provide important clues toward finding the essential conserved function of these proteins. PMID:23081703

Byrne, Keren; Leahy, Tamara; McCulloch, Russell; Colgrave, Michelle L; Holland, Michael K

2012-12-01

244

Comparison of methods for assessing integrity of equine sperm membranes.  

PubMed

Sperm membrane integrity (SMI) is thought to be an important measure of stallion sperm quality. The objective was to compare three methods for evaluating SMI: flow cytometry using SYBR-14/propidium iodide (PI) stain; an automated cell counting device using PI stain; and eosin-nigrosin stain. Raw equine semen was subjected to various treatments containing 20 to 80% seminal plasma in extender, with differing sperm concentrations, to simulate spontaneous loss of SMI. The SMI was assessed immediately, and after 1 and 2 d of cooled storage. Agreement between methods was determined according to Bland-Altman methodology. Eosin-nigrosin staining yielded higher (2%) overall mean values for SMI than did flow cytometry. Flow cytometry yielded higher (6%) overall mean values for SMI than did the automated cell counter. As percentage of membrane-damaged sperm increased, agreement of SMI measurement between methods decreased. When semen contained 50-79% membrane-intact sperm, the 95% limits of agreement between SMI determined by flow cytometry and eosin-nigrosin staining were greater (range = -26.9 to 24.3%; i.e., a 51.2% span) than for SMI determined by flow cytometry and the automated cell counter (range = -3.1 to 17.0%; 20.1% span). When sperm populations contained <50% membrane-intact sperm, the 95% limits of agreement between SMI determined by flow cytometry and eosin-nigrosin staining were greater (range = -35.9 to 19.0%; 54.9% span) than for SMI determined by flow cytometry and the automated cell counter (range = -11.6 to 28.7%; 40.3% span). We concluded that eosin-nigrosin staining assessments of percent membrane-intact sperm agreed less with flow cytometry when <80% of sperm had intact membranes, whereas automated cell counter assessments of percent membrane-intact sperm agreed less with flow cytometry when <30% of sperm had intact membranes. PMID:21496902

Foster, M L; Love, C C; Varner, D D; Brinsko, S P; Hinrichs, K; Teague, S; Lacaze, K; Blanchard, T L

2011-07-15

245

Lack of Tyrosylprotein Sulfotransferase-2 Activity Results in Altered Sperm-Egg Interactions and Loss of ADAM3 and ADAM6 in Epididymal Sperm*  

PubMed Central

Tyrosine O-sulfation is a post-translational modification catalyzed by two tyrosylprotein sulfotransferases (TPST-1 and TPST-2) in the trans-Golgi network. Tpst2-deficient mice have male infertility, sperm motility defects, and possible abnormalities in sperm-egg membrane interactions. Studies here show that compared with wild-type sperm, fewer Tpst2-null sperm bind to the egg membrane, but more of these bound sperm progress to membrane fusion. Similar outcomes were observed with wild-type sperm treated with the anti-sulfotyrosine antibody PSG2. The increased extent of sperm-egg fusion is not due to a failure of Tpst2-null sperm to trigger establishment of the egg membrane block to polyspermy. Anti-sulfotyrosine staining of sperm showed localization similar to that of IZUMO1, a sperm protein that is essential for gamete fusion, but we detected little to no tyrosine sulfation of IZUMO1 and found that IZUMO1 expression and localization were normal in Tpst2-null sperm. Turning to a discovery-driven approach, we used mass spectrometry to characterize sperm proteins that associated with PSG2. This identified ADAM6, a member of the A disintegrin and A metalloprotease (ADAM) family; members of this protein family are associated with multiple sperm functions. Subsequent studies revealed that Tpst2-null sperm lack ADAM6 and ADAM3. Loss of ADAM3 is strongly associated with male infertility and is observed in knockouts of male germ line-specific endoplasmic reticulum-resident chaperones, raising the possibility that TPST-2 may function in quality control in the secretory pathway. These data suggest that TPST-2-mediated tyrosine O-sulfation participates in regulating the sperm surface proteome or membrane order, ultimately affecting male fertility.

Marcello, Matthew R.; Jia, Weitao; Leary, Julie A.; Moore, Kevin L.; Evans, Janice P.

2011-01-01

246

Conspecific sperm precedence in Callosobruchus subinnotatus (Coleoptera: Bruchidae): mechanisms and consequences.  

PubMed

Conspecific sperm precedence (CSP) has been identified as an important post-copulatory, pre-zygotic mechanism that can act to reduce gene flow between populations. The evolution of CSP is thought to have arisen as a by-product of male and female coevolution in response to intraspecific post-copulatory sexual selection. However, little is known about the mechanisms that generate CSP. When Callosobruchus subinnotatus females copulate with both C. subinnotatus and Callosobruchus maculatus males, regardless of mating order, the majority of eggs are fertilized by conspecific sperm. The low number of heterospecific fertilizations does not result from general differences in the viability of sperm in the female reproductive tract, as heterospecific sperm fertilized equivalent numbers of eggs as conspecific sperm in the absence of sperm competition. Instead, CSP results from disadvantages to heterospecific sperm that are manifest only when in competition with conspecific sperm. CSP in C. subinnotatus appears to result from two, not mutually exclusive, mechanisms. First, conspecific sperm are better able to displace heterospecific sperm from female storage. Second, conspecific sperm achieve disproportionately higher numbers of fertilizations relative to their proportional representation in the fertilization set. Thus, we provide evidence of differential sperm use from the female spermatheca. PMID:17251102

Rugman-Jones, Paul F; Eady, Paul E

2007-04-01

247

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

PubMed

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 relationship between conventional sperm parameters and DNA integrity using acridine orange (AO) test. The study included 373 patients and 28 fertile volunteers. DNA normality was compared with semen parameters between the patient and donor populations. Significant correlations were noted between DNA normality and sperm concentration (r = 0.18, P = 0.000), motility (r = 0.21, P = 0.0001), rapid motility (0.19, P = 0.000), normal morphology by World Health Organization (r = 0.15, P = 0.019) and head defects (r = -0.15, P = 0.023). A significant difference was noted in AO levels between donors and patients with asthenozoospermia (P = 0.002) and oligoasthenozoospermia (P = 0.001). A significant difference in DNA integrity was noted in samples having <30% and >30% normal morphology. A wide range of % DNA normality was observed in the patient group. Sperm assessment for DNA status using AO is reliable and shows good correlation with sperm count, motility and morphology. Assessment of sperm DNA status with AO staining may be helpful prior to ART. PMID:19601931

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

2009-08-01

248

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

249

The computational sperm cell.  

PubMed

Sperm are guided to the egg by a gradient of chemical attractants - a process called chemotaxis. The binding of the chemoattractant to receptors on the surface of the flagellum triggers a cascade of signaling events that eventually lead to an influx of Ca(2+) ions. Based on these Ca(2+) surges, which control the waveform of the flagellar beat, sperm adjust their swimming path toward the egg. In past years, many components of chemotactic signaling have been identified. Moreover, kinetic spectroscopy and imaging techniques unraveled the sequence of cellular events controlling swimming behavior. During navigation in a chemical gradient, sperm perform a surprising variety of computational operations. Here we discuss theoretical concepts of navigation strategies and the cellular underpinnings. PMID:24342435

Alvarez, Luis; Friedrich, Benjamin M; Gompper, Gerhard; Kaupp, U Benjamin

2014-03-01

250

An automatic system to study sperm motility and energetics.  

PubMed

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

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

2008-08-01

251

Sperm count and sperm motility decrease in old rats.  

PubMed

Sexual behavior declines with age in male rats. The rate and magnitude of this decline may depend on the amount of prior sexual experience and a number of other, unidentified factors. Age-dependent changes in the characteristics of ejaculate quality in rats have not been described earlier, and the relationship between such changes and modifications of sexual behavior is likewise unknown. We have recently developed a technique for the detailed analysis of parameters of ejaculate in rats, and this technique was used for the determination of semen and seminal plug characteristics in rats of different ages. Sexually experienced Wistar rats were tested for sex behavior at the ages of 3, 12 and 24 months. Semen was obtained from the female partner immediately after ejaculation at these tests. Between tests, the males were offered the opportunity to copulate once every 3-4 weeks. The behavioral data showed that the latency to ejaculation was increased only at 24 months. Concerning the characteristics of semen, there was a substantial increase in the proportion of immobile spermatozoa and motility of those moving was much reduced, both at 12 and 24 months of age. There was no relationship between parameters of sexual behavior and those of the ejaculate. Likewise, the size of the seminal plug did not affect the amount of intrauterine spermatozoa. The reduced sperm number together with the increased sperm immobility diminishes the ejaculate quality of old males, which could influence fertility. PMID:23296084

Lucio, Rosa Angélica; Tlachi-López, José L; Eguibar, Jose R; Ågmo, Anders

2013-02-17

252

[Collagenase production increases in rheumatoid arthritis and osteoarthritis synoviocytes incubated].  

PubMed

Cartilage is a specialized connective tissue. It contains few cells into an extracell matrix. The matrix mainly constituents are collagen and proteoglycans. Its degradation depends on synoviocytes activity, that secrete metalloproteases, agents to proteoglycans catabolism. There are two types of synoviocytes: macrophagics (type "A:') and fibroblastics (type "B"). The proteoglycan destruction can be LT-dependent or LT-independent. The aim of this work is synoviocytes function ex vívo study, free immune system influence. In order to do it, heparinized synovial fluid samples were obtained from 6 osteoarthritic (OA) and 6 arthritic (RA) both sex untreated patients, diagnosed according ACR criteria, which disease duration was longer than 6 months. Patients average age was 70 +/- 2 years. Control samples were synovial fluid from traumatic arthritis or non inflammatory bone-muscle pathology. Synovial fluid was centifugated at 1500 g for 30 minutes to isolate synoviocytes. Sediment containing cells was 6 hs incubed with Dulbecco-Eagles media, that has HEPES Gibco (26 mM); NaHCO3 (0.5 g/I); glutamine (2 mM), streptomicine (100 mg/l), G-penicillin (1 U/ml); anphotericine B (2.5 mg/l). Cells calification and viability were cytopathologically determined. Before and after incubation, collagenase activity was measured by ELISA-double-sandwich, using 10 micrograms/ml monoclonal anti-MMPs in phosphate-buffer-saline. The antigen-antibody complex production with inespecific proteins was blocked by bovine seric albumine. Streptavidin peroxidase was added and washed with 2,2,azin,di(3-ethyl-benztazoilinsuiphonic) acid to develop color. The link of labeled antibody by absorbance at 410 nm was determined in ELISA-spectrophothometer. RA patients earlier MMPs synoviocytes production was 1373 +/- 115 ng/ml. Then 6 hs incubation 2143 +/- 132 ng/ml was reached. The increase (56%) had high significance (p < 0.0001). OA earlier MMPs cells production was 276 +/- 23 ng/ml, but after incubation it reached 542 +/- 47 ng/ml. (96% increased with highly significativa difference too: p < 0.0001). Microscopic study was carried out before and after incubation, and shows a lot of synoviocytes with plenty of cytopiasme when the collagenase leveis were highest. On the contrary, when low MMPs production by synovial fluid, as no incubated osteoarthritic material, a few cells containing picnotics nucleous were observed. Significant quantitative differences in AR and OA enzymatic secretion were observed. Although in rheumatoid arthritic MMPs leveis synoviocytes production were 4.6 times than OA levels, after 6 hs incubation percentage of increase in OA cells secretion was highest. Described results confirm MMP-1 synthesis by synoviocytes, and these levels correlate with inflammation, more pronounced in acute (RA) than chronic pathology (OA). Synoviocyte incubation let us to test disease changes in synovial fluid according to cells number and phagocytic activity. Authors agree to assert that synovial fluid may reflect what is happening in an articular cartilago, because SF provides markers of joint disease. MMPs are giving information about pathways involved in OA and RA cartilage degradation. PMID:11188854

Montrull, H L; Brizuela, N Y; Demurtas, S L; Strusberg, A M; Spitale, L S; Meirovich, C I

2000-01-01

253

In Vitro Production of Multigene Transgenic Blastocysts via Sperm-Mediated Gene Transfer Allows Rapid Screening of Constructs to Be Used in Xenotransplantation Experiments  

Microsoft Academic Search

Multigene transgenic pigs would be of benefit for large animal models and in particular for xenotransplantation, where extensive genetic manipulation of donor pigs is required to make them suitable for organ grafting to humans. We have previously produced multitransgenic pigs via sperm-mediated gene transfer (SMGT) using integrative constructs expressing 3 different reporter genes. The aim of the present work was

A. Vargiolu; S. Manzini; M. de Cecco; M. L. Bacci; M. Forni; G. Galeati; M. G. Cerrito; M. Busnelli; M. Lavitrano; R. Giovannoni

2010-01-01

254

Use of the Sperm Quality Analyzer (SQA II-C) for the assessment of dog sperm quality.  

PubMed

In the present study, an automated system for sperm analysis, the Sperm Quality Analyzer (SQA II-C), was tested as a potential tool for the assessment of dog sperm quality. In the first experiment the device displayed a good repeatability of measurements for semen of medium and high quality, as evidenced by a low coefficient of variance (CV; 0.08), whereas a high CV (0.46) was obtained for one dog with semen of inferior quality. In the second experiment, seven different sperm concentrations (25-300 x 106/ml), obtained by dilutions in Hepes-TALP medium were stored for 48 h at room temperature. A concentration dependent increase in sperm motility index (SMI) was shown, reaching a plateau at 150 x 106 spermatozoa/ml. For all sperm concentrations, the SMI value decreased significantly after 24 h, indicating the importance of sperm motility for SMI values. For sperm concentrations lower than 150x106/ml, highly significant correlations [r=0.80;p<0.05] were established between SMI values on one hand and sperm concentration, and semen parameters expressing the overall semen sample quality on the other hand (experiment 3) while non-significant or low correlations were found between SMI values and other individual sperm parameters. In experiment 4, significantly high correlations (r=0.97) were found between mean SMI values and post-thaw motility and progressive motility assessed subjectively. In conclusion, our study indicates that both motility and concentration largely influence SMI values and that the SQA II-C saturates at 150 x 106 fresh spermatozoa/ml. In our opinion, the SQA II-C may be a useful and objective device to assess the post-thaw motility of dog sperm. PMID:12071890

Rijsselaere, Tom; Van Soom, A; Maes, D; de Kruif, A

2002-06-01

255

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

Huyer, Marianne; Page, William J.

1988-01-01

256

Novel approach for immersion lithography defectivity control to increase productivity  

NASA Astrophysics Data System (ADS)

Increase of Depth of Focus (DOF) and higher Numerical Aperture (NA), make of immersion lithography a sub-50nm technology node enabler. At the same time it introduces a range of new defect types, also known as immersion defects. According to the ITRS roadmap, the Smallest Defect Of Interest (SDOI) for the 45nm node has a size of 30nm [1] which is the minimal defect size which poses risk to the integrity of the post litho chain processes. A novel approach of Immersion Defectivity Baseline creation and monitoring has been developed for the 45nm technology node by ASML, supported by Applied Materials. An Immersion Defectivity Baseline consists of: a qualified stack, a dedicated defectivity reticle, a Defect Inspection Tool with an optimized inspection recipe, a Defect Review SEM with an optimized defect review recipe and a defect qualification scheme. The new approach to Immersion Defectivity Baseline creation is based on the combined capabilities of highest resolution bright-field inspection and SEM (Scanning Electron Microscopy) review that are available today, with a unique qualification methodology using printed programmed defects that cover the full printable size range. The inspection tool's SDOI detection sensitivity has been optimized for engineering, production as well as monitoring modes, with negligible nuisance rate and basic classification capability followed by highly accurate SEM review and classification. As a result, it enables a stringently controlled, highly efficient, automated defect classification for baseline monitoring and increased productivity. The SEM material analysis sub-apparatus complete the control loop for baseline creation and excursion control. This paper presents a protocol for Immersion Defectivity Baseline creation and control methodologies used for the latest ASML immersion scanner.

Englard, Ilan; Stegen, Raf; Vanoppen, Peter; Minnaert-Janssen, Ingrid; der Kinderen, Ted; van Brederode, Erik; Duray, Frank; Linders, Jeroen; Ovchinnikov, Denis; Piech, Rich; Masia, Claudio; Hillel, Noam; Ravid, Erez; Rotlevi, Ofer; Wilde, Amir; Shabtay, Saar; Telor, Zach; Schreutelkamp, Robert

2008-04-01

257

Methods for the analysis of the sperm proteome.  

PubMed

Proteomics is the study of the proteins of cells or tissues. Sperm proteomics aims at the identification of the proteins that compose the sperm cell and the study of their function. The recent developments in mass spectrometry (MS) have markedly increased the throughput for the identification and study of the sperm proteins. Catalogues of spermatozoal proteins in human and in model species are becoming available laying the groundwork for subsequent research, diagnostic applications, and the development of patient-specific treatments. A wide range of MS techniques is also rapidly becoming available for researchers. This chapter describes a methodological option to study the sperm cell using MS and provides a detailed protocol to identify the proteins extracted from a Percoll-purified human sperm population and separated by two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) using LC-MS/MS. PMID:22992932

de Mateo, Sara; Estanyol, Josep Maria; Oliva, Rafael

2013-01-01

258

Power Production at Federal Dams Could Be Increased By Modernizing Turbines and Generators.  

National Technical Information Service (NTIS)

Existing Federal hydroelectric plants could increase power production by modernizing turbines to increase efficiencies and capacities and by modernizing generators to increase capacities. Increasing hydroelectric power production will (1) increase the Nat...

1977-01-01

259

Sperm competition roles and ejaculate investment in a promiscuous mammal.  

PubMed

Theoretical models of sperm competition predict how males should allocate sperm and seminal fluid components to ejaculates according to their mating role (dominant vs. subordinate). Here, we present a detailed analysis of ejaculate expenditure according to male roles in the bank vole (Myodes glareolus). Sperm competition occurs regularly in this species, and dominant males typically achieve higher fertilization success than subordinates. Contrary to theoretical predictions, we found that dominant male bank voles invest more sperm per ejaculate than subordinates, both absolutely and relative to body and testes mass. The testes of dominant males were also absolutely (although not relatively) larger than those of subordinates. However, we found no evidence that subordinate males compensate for lower sperm numbers per ejaculate by increasing ejaculation frequency or sperm velocity. Similarly, we found no evidence for differential investment in copulatory plug size according to male roles in sperm competition, although dominant males had significantly larger seminal vesicles (both absolutely and relative to body mass) compared with subordinates. We conclude that sperm competition roles can have significant but unexpected influences on ejaculate investment in mammals with clearly defined differences in male social status. PMID:22515660

Lemaître, J-F; Ramm, S A; Hurst, J L; Stockley, P

2012-06-01

260

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.

2014-01-01

261

Stability, delivery and functions of human sperm RNAs at fertilization  

PubMed Central

Increasing attention has focused on the significance of RNA in sperm, in light of its contribution to the birth and long-term health of a child, role in sperm function and diagnostic potential. As the composition of sperm RNA is in flux, assigning specific roles to individual RNAs presents a significant challenge. For the first time RNA-seq was used to characterize the population of coding and non-coding transcripts in human sperm. Examining RNA representation as a function of multiple methods of library preparation revealed unique features indicative of very specific and stage-dependent maturation and regulation of sperm RNA, illuminating their various transitional roles. Correlation of sperm transcript abundance with epigenetic marks suggested roles for these elements in the pre- and post-fertilization genome. Several classes of non-coding RNAs including lncRNAs, CARs, pri-miRNAs, novel elements and mRNAs have been identified which, based on factors including relative abundance, integrity in sperm, available knockout data of embryonic effect and presence or absence in the unfertilized human oocyte, are likely to be essential male factors critical to early post-fertilization development. The diverse and unique attributes of sperm transcripts that were revealed provides the first detailed analysis of the biology and anticipated clinical significance of spermatozoal RNAs.

Sendler, Edward; Johnson, Graham D.; Mao, Shihong; Goodrich, Robert J.; Diamond, Michael P.; Hauser, Russ; Krawetz, Stephen A.

2013-01-01

262

Group X phospholipase A2 is released during sperm acrosome reaction and controls fertility outcome in mice.  

PubMed

Ejaculated mammalian sperm must undergo a maturation process called capacitation before they are able to fertilize an egg. Several studies have suggested a role for members of the secreted phospholipase A2 (sPLA2) family in capacitation, acrosome reaction (AR), and fertilization, but the molecular nature of these enzymes and their specific roles have remained elusive. Here, we have demonstrated that mouse group X sPLA2 (mGX) is the major enzyme present in the acrosome of spermatozoa and that it is released in an active form during capacitation through spontaneous AR. mGX-deficient male mice produced smaller litters than wild-type male siblings when crossed with mGX-deficient females. Further analysis revealed that spermatozoa from mGX-deficient mice exhibited lower rates of spontaneous AR and that this was associated with decreased in vitro fertilization (IVF) efficiency due to a drop in the fertilization potential of the sperm and an increased rate of aborted embryos. Treatment of sperm with sPLA2 inhibitors and antibodies specific for mGX blocked spontaneous AR of wild-type sperm and reduced IVF success. Addition of lysophosphatidylcholine, a catalytic product of mGX, overcame these deficiencies. Finally, recombinant mGX triggered AR and improved IVF outcome. Taken together, our results highlight a paracrine role for mGX during capacitation in which the enzyme primes sperm for efficient fertilization and boosts premature AR of a likely phospholipid-damaged sperm subpopulation to eliminate suboptimal sperm from the pool available for fertilization. PMID:20424324

Escoffier, Jessica; Jemel, Ikram; Tanemoto, Akemi; Taketomi, Yoshitaka; Payre, Christine; Coatrieux, Christelle; Sato, Hiroyasu; Yamamoto, Kei; Masuda, Seiko; Pernet-Gallay, Karin; Pierre, Virginie; Hara, Shuntaro; Murakami, Makoto; De Waard, Michel; Lambeau, Gérard; Arnoult, Christophe

2010-05-01

263

Group X phospholipase A2 is released during sperm acrosome reaction and controls fertility outcome in mice  

PubMed Central

Ejaculated mammalian sperm must undergo a maturation process called capacitation before they are able to fertilize an egg. Several studies have suggested a role for members of the secreted phospholipase A2 (sPLA2) family in capacitation, acrosome reaction (AR), and fertilization, but the molecular nature of these enzymes and their specific roles have remained elusive. Here, we have demonstrated that mouse group X sPLA2 (mGX) is the major enzyme present in the acrosome of spermatozoa and that it is released in an active form during capacitation through spontaneous AR. mGX-deficient male mice produced smaller litters than wild-type male siblings when crossed with mGX-deficient females. Further analysis revealed that spermatozoa from mGX-deficient mice exhibited lower rates of spontaneous AR and that this was associated with decreased in vitro fertilization (IVF) efficiency due to a drop in the fertilization potential of the sperm and an increased rate of aborted embryos. Treatment of sperm with sPLA2 inhibitors and antibodies specific for mGX blocked spontaneous AR of wild-type sperm and reduced IVF success. Addition of lysophosphatidylcholine, a catalytic product of mGX, overcame these deficiencies. Finally, recombinant mGX triggered AR and improved IVF outcome. Taken together, our results highlight a paracrine role for mGX during capacitation in which the enzyme primes sperm for efficient fertilization and boosts premature AR of a likely phospholipid-damaged sperm subpopulation to eliminate suboptimal sperm from the pool available for fertilization.

Escoffier, Jessica; Jemel, Ikram; Tanemoto, Akemi; Taketomi, Yoshitaka; Payre, Christine; Coatrieux, Christelle; Sato, Hiroyasu; Yamamoto, Kei; Masuda, Seiko; Pernet-Gallay, Karin; Pierre, Virginie; Hara, Shuntaro; Murakami, Makoto; De Waard, Michel; Lambeau, Gerard; Arnoult, Christophe

2010-01-01

264

Relationships between sperm length and speed differ among three internally and three externally fertilizing species.  

PubMed

It is often assumed that longer sperm, by virtue of their increased swimming speed, have a fertilization advantage over shorter sperm when in competition to fertilize eggs. However, there is surprisingly little evidence for a positive correlation between sperm length and speed. Here we use an approach that accounts for within-male variation in sperm traits to examine the relationships between sperm length and sperm speed across a broad range of species, including three internally fertilizing species and three externally fertilizing species. Our results reveal that correlations between sperm size and speed are indeed present and possibly more common than currently thought. However, the direction of the correlations between sperm length and speed, which are more prevalent within a male's ejaculate than among males, were influenced by fertilization mode in contrasting and unexpected ways. Broadly, the patterns revealed that in externally fertilizing species sperm with longer flagellum and shorter heads relative to their flagellum swam faster, whereas in internally fertilizing species sperm with shorter flagellum and longer heads relative to their flagellum swam faster. We discuss these results in light of sperm competition theory and contrast the intraspecific patterns observed in this study with macroevolutionary patterns of sperm evolution reported elsewhere. PMID:24224469

Simpson, Julia L; Humphries, Stuart; Evans, Jonathan P; Simmons, Leigh W; Fitzpatrick, John L

2014-01-01

265

Raman spectroscopy of DNA packaging in individual human sperm cells distinguishes normal from abnormal cells.  

PubMed

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. PMID:19373853

Huser, Thomas; Orme, Christine A; Hollars, Christopher W; Corzett, Michele H; Balhorn, Rod

2009-05-01

266

Response of boar sperm to the treatment with cholesterol-loaded cyclodextrins added prior to cryopreservation.  

PubMed

Cryopreserved boar sperm is not used extensively for artificial insemination, owing to the poor fertility rates of the sperm after freezing and thawing. The sperm membrane is damaged as the cells are cooled from body temperature to 5°C (cold shock), as well as during the freeze-thaw process. Increasing the cholesterol content of boar sperm membranes could help them survive cryopreservation, similar to sperm from other species that are cold shock sensitive. The aim of this study was to determine the optimal cholesterol-loaded cyclodextrin (CLC) concentration to use for boar sperm cryopreservation, and the influence of CLCs on the cryosurvival of sperm from boars classified as good or poor freezers. Treating boar sperm with 1 mg of CLC/120 × 10(6) sperm slightly improved (p < 0.05) the percentage of viable sperm after freezing-thawing. On the other hand, sperm, from both good and poor freezers, responded similarly to CLC treatment. Nevertheless, additional studies will be needed to study the effect of this treatment on other parameters of sperm quality. PMID:22372766

Blanch, E; Tomás, C; Graham, J K; Mocé, E

2012-12-01

267

Effects of chloroformic extracts from washed and unwashed papaya seeds (Carica papaya) on the sperm concentration of dogs.  

PubMed

Papaya seeds (Carica papaya Linn) have been found to have a significant effect on sperm characteristics in some mammals, including humans, but no studies have investigated the effects on dogs. In the present study, a significant decrease in sperm concentration was observed in a group of dogs treated with extracts from washed papaya seeds, but no decrease was observed in the group of dogs treated with non-washed seeds. An important effect of extract components from washed seeds such as fatty acids is probably involved in the reduction of sperm production because of Sertoli cell damage, as has been suggested for langur monkeys. Dilution of the active components in the non-washed papaya seeds or interference with some of the components may reduce the expected effect on spermatogenesis. This first report on the effects of a chloroformic extract of papaya seeds in dogs suggests that an increased dose is necessary to achieve azoospermia. PMID:19650877

Ortega-Pacheco, A; Jiménez-Coello, M; Gutiérrez-Blanco, E; Acosta-Viana, K Y; Guzmán-Marín, E; Zavala-Sánchez, M A; Montalvo-Beltrán, N E; Pérez-Gutiérrez, M S

2010-12-01

268

Effect of various commercial buffers on sperm viability and capacitation.  

PubMed

Abstract 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

269

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.

Keber, Rok; Rozman, Damjana; Horvat, Simon

2013-01-01

270

Enhanced membrane protein expression by engineering increased intracellular membrane production  

PubMed Central

Background Membrane protein research is frequently hampered by the low natural abundance of these proteins in cells and typically relies on recombinant gene expression. Different expression systems, like mammalian cells, insect cells, bacteria and yeast are being used, but very few research efforts have been directed towards specific host cell customization for enhanced expression of membrane proteins. Here we show that by increasing the intracellular membrane production by interfering with a key enzymatic step of lipid synthesis, enhanced expression of membrane proteins in yeast is achieved. Results We engineered the oleotrophic yeast, Yarrowia lipolytica, by deleting the phosphatidic acid phosphatase, PAH1, which led to massive proliferation of endoplasmic reticulum (ER) membranes. For all eight tested representatives of different integral membrane protein families, we obtained enhanced protein accumulation levels and in some cases enhanced proteolytic integrity in the ?pah1 strain. We analysed the adenosine A2AR G-protein coupled receptor case in more detail and found that concomitant induction of the unfolded protein response in the ?pah1 strain enhanced the specific ligand binding activity of the receptor. These data indicate an improved quality control mechanism for membrane proteins accumulating in yeast cells with proliferated ER. Conclusions We conclude that redirecting the metabolic flux of fatty acids away from triacylglycerol- and sterylester-storage towards membrane phospholipid synthesis by PAH1 gene inactivation, provides a valuable approach to enhance eukaryotic membrane protein production. Complementary to this improvement in membrane protein quantity, UPR co-induction further enhances the quality of the membrane protein in terms of its proper folding and biological activity. Importantly, since these pathways are conserved in all eukaryotes, it will be of interest to investigate similar engineering approaches in other cell types of biotechnological interest, such as insect cells and mammalian cells.

2013-01-01

271

Hyperoxia increases hepatic arginase expression and ornithine production in mice  

SciTech Connect

Hyperoxic exposure affects the levels and activities of some hepatic proteins. We tested the hypothesis that hyperoxic exposure would result in greater hepatic .NO concentrations. C3H/HeN mice were exposed to >95% O{sub 2} for 72 or 96 h and compared to room air-breathing controls. In contrast to our working hypothesis, exposure to >95% O{sub 2} for 96 h decreased hepatic nitrite/nitrate NO {sub X} concentrations (10.9 {+-} 2.2 nmol/g liver versus 19.3 {+-} 2.4 nmol/g liver in room air, P < 0.05). The hepatic levels of endothelial NO synthase (eNOS) and inducible NOS (iNOS) proteins were not different among the groups. The arginases, which convert L-arginine to urea and L-ornithine, may affect hepatic NOS activities by decreasing L-arginine bioavailability. Hepatic ornithine concentrations were greater in hyperoxic animals than in controls (318 {+-} 18 nmol/g liver in room air, and 539 {+-} 64, and 475 {+-} 40 at 72 and 96 h of hyperoxia, respectively, P < 0.01). Hepatic arginase I protein levels were greater in hyperoxic animals than in controls. Hepatic carbamoyl phosphate synthetase (CPS) protein levels and activities were not different among groups. These results indicate that increases in hepatic levels of arginase I in mice exposed to hyperoxia may diminish .NO production, as reflected by lower liver levels of NO {sub X}. The resultant greater hepatic ornithine concentrations may represent a mechanism to facilitate tissue repair, by favoring the production of polyamines and/or proline.

Malleske, Daniel T. [Center for Developmental Pharmacology and Toxicology, Columbus Children's Research Institute, Department of Pediatrics, Ohio State University, Columbus, OH 43205 (United States); Rogers, Lynette K. [Center for Developmental Pharmacology and Toxicology, Columbus Children's Research Institute, Department of Pediatrics, Ohio State University, Columbus, OH 43205 (United States); Velluci, Sean M. [Center for Developmental Pharmacology and Toxicology, Columbus Children's Research Institute, Department of Pediatrics, Ohio State University, Columbus, OH 43205 (United States); Young, Tamara L. [Center for Developmental Pharmacology and Toxicology, Columbus Children's Research Institute, Department of Pediatrics, Ohio State University, Columbus, OH 43205 (United States); Park, Min S. [Center for Developmental Pharmacology and Toxicology, Columbus Children's Research Institute, Department of Pediatrics, Ohio State University, Columbus, OH 43205 (United States); Long, Donald W. [Center for Developmental Pharmacology and Toxicology, Columbus Children's Research Institute, Department of Pediatrics, Ohio State University, Columbus, OH 43205 (United States); Welty, Stephen E. [Center for Developmental Pharmacology and Toxicology, Columbus Children's Research Institute, Department of Pediatrics, Ohio State University, Columbus, OH 43205 (United States); Smith, Charles V. [Center for Developmental Pharmacology and Toxicology, Columbus Children's Research Institute, Department of Pediatrics, Ohio State University, Columbus, OH 43205 (United States); Nelin, Leif D. [Center for Developmental Pharmacology and Toxicology, Columbus Children's Research Institute, Department of Pediatrics, Ohio State University, Columbus, OH 43205 (United States)]. E-mail: NelinL@pediatrics.ohio-state.edu

2006-08-15

272

Royal Jelly Increases Collagen Production in Rat Skin After Ovariectomy  

PubMed Central

Abstract 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.

Park, Hye Min; Cho, Min Hyoung; Cho, Yunhi

2012-01-01

273

Sperm dynamics in spiders  

Microsoft Academic Search

Behavioral studies of sexual selection tend to focus on events that lead up to copulation and the transfer of sperm. Not surprisingly, we know most about how the selective forces prior to copulation act on female choice and male--male competition. The playground for postcopulatory processes is the female genital tract where we expect male and female adaptations to control fertilization.

M. E. Herberstein; J. M. Schneider; G. Uhl; P. Michalik

2011-01-01

274

Sperm motion analysis  

Microsoft Academic Search

This paper presents a computerized technique for quantitative analysis of the movement characteristics of spermatozoa. Stored video images of spermatozoa are digitized at a fixed time interval. The digital images are stored as a sequence of frames in a microcomputer. The analysis of the sequence comprises two main tasks: finding the location of the centroid for each sperm and tracking

Valiollah Salari

1991-01-01

275

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.

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

2014-01-01

276

Improved Work Measurement Program Would Increase DoD Productivity.  

National Technical Information Service (NTIS)

For many years, the Department of Defense (DOD) has had programs aimed at improving, measuring, and evaluating its internal productivity. Because work measurement has proven to be an effective productivity-enhancing technique, it has always played a major...

1981-01-01

277

The shape of the sperm midpiece in intracytoplasmic morphologically selected sperm injection relates sperm centrosomal function  

Microsoft Academic Search

Purpose  To evaluate whether the morphology of the sperm midpiece observed by high magnification microscopy relates to sperm centrosomal\\u000a function.\\u000a \\u000a \\u000a \\u000a \\u000a Methods  Sperm selected by conventional microscopy were defined as controls. By high magnification microscopy, sperm with straight\\u000a midpieces were defined as Group 1, while those with tapering midpieces were defined as Group 2. Heterologous ICSI of human\\u000a sperm into bovine oocytes was

Tomohisa Ugajin; Yukihiro Terada; Hisataka Hasegawa; Hiroshi Nabeshima; Kichiya Suzuki; Nobuo Yaegashi

2010-01-01

278

Relationship between bull field fertility and in vitro embryo production using sperm preparation methods with and without somatic cell co-culture.  

PubMed

Experiments were designed to compare rates of embryonic development following oocyte exposure to cryopreserved spermatozoa from bulls of varying proven fertility, utilizing 3 different sperm preparation methods prior to oocyte introduction. These included 1) sperm co-culture with bovine oviductal epithelial cells (BOEC); 2) sperm co-culture with buffalo rat liver cells (BRLC); or 3) control culture in a routine, cell-free culture system. Semen from 9 bulls was classified by lifetime 60- to 90-d nonreturn rates as having either (mean +/- SEM) high (n=3) 73.2 +/- 3a, medium (n=3) 70.3 +/- 2b or low (n=3) 65.8 +/- 3c field fertility ((ac)p< 0.01; (bc)p< 0.05). There was no difference in embryo cleavage rates for spermatozoa from the high (58 +/- 18%), medium (57 +/-23%) or low (57 +/- 18%) fertility groups. Development to morula or beyond of oocytes fertilized with high (53 +/- 30%) or low (58 +/- 27%) fertility semen tended (P<0.10) to be higher than of those fertilized with medium fertility (33 +/- 28%) semen. This lack of relationship between in vivo fertility and in vitro embryo outcome was consistent across all sperm preparation methods. Therefore, pooled data were used to evaluate the effect of sperm preparation on embryo outcome. There was no difference in embryo cleavage rates between BOEC monolayers (51 +/- 22%), BRLC monolayers (60 +/- 20%) and the cell-free controls (60 +/- 17%). Subsequent embryonic development to compact morula and beyond was higher (P<0.01) with the BRLC monolayer treatment (61 +/- 28%) than with the BOEC monolayers (42 +/- 33%) or control culture (39 +/- 24%). In conclusion, these studies suggest that there is no predictive relationship between bull field fertility (in the ranges evaluated here) and in vitro embryo cleavage or development rates. However, oocytes inseminated with sperm cells co-cultured on BRLC monolayers develop to the morula stage or beyond at a higher rate than oocytes inseminated with spermatozoa from the BOEC or cell-free system. PMID:10729028

Schneider, C S; Ellington, J E; Wright, R W

1999-04-15

279

Does product development success increase as disruptive technologies are evaluated?  

Microsoft Academic Search

This paper reviews new product development projects published previously and examines how companies define their next generation of products and develop them while watching the market for potential disruptive technologies and take precautions for those with potential to influence the market place. The study includes a quantification methodology of the product development capabilities of the companies discussed in the case

T. U. Daim; Y. Daim

1999-01-01

280

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

281

Drill-in fluid reduces formation damage, increases production rates  

Microsoft Academic Search

A sodium formate drill-in fluid system reduced formation damage, resulting in better-than-expected production rates for an off-shore Dutch development well. Programmed to optimize production capacity and reservoir drainage from a Rotliegend sandstone gas discovery, the 5-7\\/8-in. subhorizontal production interval was drilled and completed barefoot with a unique, rheologically engineered sodium formate drill-in fluid system. The new system, consisting of a

N. Hands; K. Kowbel; S. Maikranz; R. Nouris

1998-01-01

282

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

283

Sperm storage in male elasmobranchs: a description and survey.  

PubMed

Two basic types of spermatozoan aggregates, spermatophores and spermatozeugmata, found in 14 different species of sharks, one species of skate, and one species of chimaera (holocephalan), were investigated using light and scanning electron microscopy. Spermatophores, aggregates (usually 1,000-6,000 microns in diameter and larger) of randomly clumped sperm embedded in and surrounded by an eosinophilic matrix, were found in Alopias superciliosus, Odontaspis taurus, Carcharodon carcharias, Isurus oxyrinchus, and Lamna nasus. Three types of spermatozeugmata, sperm structures without a surrounding capsule or matrix, are described. The first, clumps of 60-200 sperm unbound in a supporting matrix, are found in Squalus acanthias and Hydrolagus colliei. In the second type, single-layered spheres are formed of sperm clumps with the sperm heads bound in a common supporting matrix. These are found in Carcharhinus limbatus and Carcharhinus plumbeus. The third type of spermatozeugmata are large multilayered, compound structures formed by the accretion of several single-layered aggregates. These multilayered structures characteristically are found in Carcharhinus falciformis, C. limbatus, Carcharhinus obscurus, C. plumbeus, Carcharhinus porosus, Prionace glauca, Rhizoprionodon terraenovae, and Sphyrna lewini. Sperm aggregates of all types are stored between the septa and in the lumen of the terminal ampulla of the epididymis. In their various forms they are the final product of the mature male elasmobranch reproductive tract. In a male with mature claspers, the presence of sperm aggregates is a more reliable indicator of maturity and sexual activity than is clasper condition alone. PMID:8169955

Pratt, H L; Tanaka, S

1994-03-01

284

Use of a sperm quality analyser on semen of turkey breeders to monitor storage time effects and age-related changes during a reproductive cycle.  

PubMed

1. A relatively new instrument known as a Sperm Quality Analyzer (SQA) offers a rapid assessment of sperm quality and quantity by providing a sperm quality index (SQI). The SQA measures the intensity of sperm activity and motile concentration by determining the number and amplitude of sperm movements per second in a capillary tube as detected through light beam interference. 2. The objectives of the current study were to determine if the SQA could accurately reflect changes in semen quality that occur with prolonged storage of semen and to determine the variation and change in SQI values among individual breeding male turkeys during their semen production cycle. 3. The effect of storage time on SQI values was evaluated by diluting semen with extender and placing the semen on an oscillating shaker at 4 degrees C for 8 h. The SQI values and sperm viability, expressed as % dead sperm, were recorded hourly. The SQI readings declined linearly with increased storage time while % dead sperm increased linearly with increased semen storage. 4. Semen from 220 individual males was analysed monthly for 9 months. Semen diluted 50-fold with saline had lower SQI values during pre- and post-peak phases of production (months 1, 7, 8, and 9 as compared with months 2 to 6 of semen production). The highest SQI values occurred during months 2 to 6. The largest variation in SQI values occurred during months 1 (CV = 26%) and 9 (CV = 31%) with a CV that averaged 16% for the remaining months. 5. Correlation analysis of SQI values for each bird averaged over 9 months with individual male SQIs for each month showed monthly correlation coefficients that ranged from 0.22 to 0.63. 6. These results indicate that the SQA accurately assessed the decline in sperm quality that occurs with prolonged storage of turkey semen and reflected age-related changes in semen quality and quantity that occurred during a semen production cycle of turkey breeders. In addition, the semen quality rank of some turkey breeders in a population changed with age. PMID:12195807

Neuman, S L; McDaniel, C D; Frank, L; Radu, J; Hester, P Y

2002-07-01

285

The sperm proteasome during sperm capacitation and fertilization.  

PubMed

The 26S proteasome is a multi-subunit protease specifically targeting ubiquitinated proteins. A consensus has emerged from studies by multiple laboratories on the role of sperm-borne proteasomes in human, mouse, pig, bovine, ascidian and echinoderm fertilization. Major findings from the studies in various mammalian and non-mammalian fertilization systems are (1) proteasomes are present in the mammalian sperm acrosome and on the acrosomal surface; (2) ubiquitinated proteins are present on the mammalian, ascidian and echinoderm egg coat; (3) proteasomal proteolytic and ubiquitin-deconjugating (deubiquitinating) activities can be detected in viable, motile mammalian spermatozoa; (4) proteasomes remain associated with the sperm head following ZP-induced acrosomal exocytosis; (5) inhibition of ubiquitination and proteasomal proteolysis blocks fertilization in mammals, ascidians and echinoderms; (6) inhibition of proteasomal proteolysis alters the course of mammalian sperm capacitation and acrosomal exocytosis induced by sperm binding to the egg coat, zona pellucida (ZP); (7) depletion of the sperm surface-associated ATP blocks porcine and echinoderm fertilization, most likely by affecting the integrity of sperm proteasomes, of which several subunits are ATPases; (8) inhibition of proteasomal proteolysis blocks sperm-ZP penetration, but does not alter the rate of sperm-ZP binding in mammals, and (9) experimental modification of sperm-associated deubiquitinating activities shifts the balance of monospermic fertilization to polyspermic fertilization in vitro. Altogether, these studies provide evidence for the involvement of the 26S proteasome in multiple steps of animal and human fertilization, offering a novel model of sperm-egg coat interactions, and identifying a range of potential new sperm quality markers and contraceptive targets. PMID:19853307

Zimmerman, Shawn; Sutovsky, Peter

2009-12-01

286

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.

Yang, Huiping; Tiersch, Terrence R.

2009-01-01

287

Sperm abnormalities in post-thawed semen of Tunisian Arab stallions.  

PubMed

The study was undertaken in order to evaluate sperm morphology features of post-thawed semen of Tunisian Arab stallions. Forty two ejaculates was collected and frozen, during years 2009 and 2010, from 9 stallions aged between 9 to 24 years. After thawing, sperm morphology was studied after eosin-nigrosin stain. The percentages of abnormal head, mid piece, flagella, sperm with droplets and the total abnormal sperm were determined. Analysis of variance was carried out using SAS software. The results showed that all sperm morphology features varied among ejaculates within stallion and among stallions (p<0.01). The percentage of abnormal flagella and total abnormal sperm varied between young and old stallions (p<0.01). We concluded that freezing and thawing processes increased abnormal sperm that is due to cell alteration for old and young stallions, and consequently, the decrease of the quality of the thawed semen of Tunisian Arab stallions. PMID:24502174

Najjar, A; Ben Said, S; Benaoun, B; Chetoui, C; Ezzaouia, M; Ben Mrad, M

2013-10-01

288

Delivering cholesterol or cholestanol to bull sperm membranes improves cryosurvival  

Microsoft Academic Search

This study compared the effect of adding other cholesterol conjugates, which should incorporate into and increase sperm membrane fluidity at low temperatures thereby increasing cryosurvival. Ejaculates from each of four bulls were diluted to 120million cells\\/ml in a Tris diluent and used in two experiments. Each experiment contained four treatments: No additive (control); 1.5mg CLC\\/120million sperm (positive control); and 1.5mg

E. A. Moraes; J. K. Graham; C. A. A. Torres; M. Meyers; B. Spizziri

2010-01-01

289

Does tree diversity increase wood production in pine forests?  

Microsoft Academic Search

Recent experimental advances on the positive effect of species richness on ecosystem productivity highlight the need to explore this relationship in communities other than grasslands and using non-synthetic experiments. We investigated whether wood production in forests dominated by Aleppo pine (Pinus halepensis) and Pyrenean Scots pine (Pinus sylvestris) differed between monospecific and mixed forests (2-5 species) using the Ecological and

Montserrat Vilà; Jordi Vayreda; Carles Gracia; Joan Josep Ibáñez

2003-01-01

290

Hyperactivated sperm motility driven by CatSper2 is required for fertilization  

PubMed Central

Elevations of sperm Ca2+ seem to be responsible for an asymmetric form of motility called hyperactivation, which is first seen near the time of fertilization. The mechanism by which intracellular Ca2+ concentrations increase remains unknown despite considerable investigation. Although several prototypical voltage-gated calcium channels are present in spermatozoa, they are not essential for motility. Furthermore, the forward velocity and percentage of motility of spermatozoa are associated with infertility, but their importance relative to hyperactivation also remains unknown. We show here that disruption of the gene for a recently described sperm-specific voltage-gated cation channel, CatSper2, fails to significantly alter sperm production, protein tyrosine phosphorylation that is associated with capacitation, induction of the acrosome reaction, forward velocity, or percentage of motility, yet CatSper2–/– males are completely infertile. The defect that we identify in the null sperm cells is a failure to acquire hyperactivated motility, which seems to render spermatozoa incapable of generating the “power” needed for penetration of the extracellular matrix of the egg. A loss of power is suggested also by experiments in which the viscosity of the medium was increased after incubation of spermatozoa in normal capacitating conditions. In high-viscosity medium, CatSper2-null spermatozoa lost the ability to swim forward, whereas wild-type cells continued to move forward. Thus, CatSper2 is responsible for driving hyperactivated motility, and, even with typical sperm forward velocities, fertilization is not possible in the absence of this highly active form of motility.

Quill, Timothy A.; Sugden, Sarah A.; Rossi, Kristen L.; Doolittle, Lynda K.; Hammer, Robert E.; Garbers, David L.

2003-01-01

291

Application of intracytoplasmic sperm injection (ICSI) for fertilization and development in birds.  

PubMed

Intracytoplasmic sperm injection (ICSI) technology in birds has been hampered due to opacity of oocyte. We developed ICSI-assisted fertilization and gene transfer in quail. This paper reviews recent advances of our ICSI experiments. The oocyte retrieved from the oviduct and a quail sperm was injected into the oocyte under a stereomicroscope. The oocyte was cultured for 24h at 41°C under 5% CO2 in air. The fertilization and development was assessed by microscopic observation. The fertility rate ranged 12-18% and development varied from stage II to V in trials. To improve the fertility rate, phospholipase C (PLC) zeta was injected with a sperm. It was increased to 37-50%. Furthermore, injection of inositol trisphosphate increased to over 85%. Quail oocyte can be fertilized with chicken sperm and so can testicular elongated spermatid. To extend embryonic development, chicken eggshell was used as a surrogate culture at 37°C after the 24h incubation at 41°C under 5% CO2 in air. It survived up to 2days thereafter. Finally, gene transfer was attempted in quail egg. The sperm membrane was disrupted with Triton X-100 (TX-100) and was injected with PLCzeta cRNA and enhanced green fluorescent protein (EGFP) gene in oocyte. The GFP expression was evaluated at 24h incubation at 41°C under 5% CO2 in air in the embryos. While the expression was not detected in the control oocytes, the experimental treatment induced blastoderm development (44%) of the oocytes and 86% of blastoderm showed fluorescent emission. In addition, PCR analysis detected EGFP fragments in 50% of GFP-expressing blastoderm. Our ICSI method may be the first step toward the production of transgenic birds. PMID:24239795

Shimada, Kiyoshi; Ono, Tamao; Mizushima, Shusei

2014-01-15

292

Detection and tracking of low contrast human sperm tail  

Microsoft Academic Search

Tracking sperm tail movement provides important information for clinical sperm research. It is also a crucial step for sperm immobilization in Intracytoplasmic Sperm Injection (ICSI). However, the low visibility of the sperm tail under optical microscopy, coupled with the sperm fast motility, render sperm tail identification and tracking challenging tasks to execute. This paper presents two approaches for sperm tail

Clement Leung; Zhe Lu; Navid Esfandiari; Robert F. Casper; Yu Sun

2010-01-01

293

Biodiversity increases the productivity and stability of phytoplankton communities.  

PubMed

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

294

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

295

Angiotensin II stimulates sperm motility.  

PubMed

The physiological factors which induce and maintain mammalian sperm maturation and motility generally remain unclear, although several agents are known to be involved. We recently described the application of immunocytochemical and immunoblotting methods to identify the angiotensin II type 1 (AT1) receptor in the tails of ejaculated rat and human sperm, and gave evidence to show that angiotensin II may promote sperm motility. These data are extended here by the application of a computerised sperm tracking system (the Hobson Sperm Tracker) to demonstrate that AII has actions on specific motility parameters, including curvilinear velocity, straight line velocity, and amplitude of lateral head movement. Since local tissue renin-angiotensin systems are present in both male and female tracts, the data suggest that angiotensin II has a role in the maintenance of sperm function and fertility. PMID:8958584

Vinson, G P; Mehta, J; Evans, S; Matthews, S; Puddefoot, J R; Saridogan, E; Holt, W V; Djahanbakhch, O

1996-12-01

296

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.

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

2013-01-01

297

Sperm cell proteomics.  

PubMed

The spermatozoon is an accessible cell which can be easily purified and therefore it is particularly well suited for proteomic analysis. It is also an extremely differentiated cell with very marked genetic, cellular, functional and chromatin changes as compared to other cells, and has profound implications for fertility, embryo development and heredity. The recent developments in MS have boosted the potential for identification and study of the sperm proteins. Catalogues of hundreds to thousands of spermatozoan proteins in human and in model species are becoming available setting up the basis for subsequent research, diagnostic applications and the development of specific treatments. The present article reviews the available scientific publications dealing with the composition and function of the sperm cell using an MS proteomic approach. PMID:19212950

Oliva, Rafael; de Mateo, Sara; Estanyol, Josep Maria

2009-02-01

298

Genome amplification of single sperm using multiple displacement amplification  

PubMed Central

Sperm typing is an effective way to study recombination rate on a fine scale in regions of interest. There are two strategies for the amplification of single meiotic recombinants: repulsion-phase allele-specific PCR and whole genome amplification (WGA). The former can selectively amplify single recombinant molecules from a batch of sperm but is not scalable for high-throughput operation. Currently, primer extension pre-amplification is the only method used in WGA of single sperm, whereas it has limited capacity to produce high-coverage products enough for the analysis of local recombination rate in multiple large regions. Here, we applied for the first time a recently developed WGA method, multiple displacement amplification (MDA), to amplify single sperm DNA, and demonstrated its great potential for producing high-yield and high-coverage products. In a 50 ?l reaction, 76 or 93% of loci can be amplified at least 2500- or 250-fold, respectively, from single sperm DNA, and second-round MDA can further offer >200-fold amplification. The MDA products are usable for a variety of genetic applications, including sequencing and microsatellite marker and single nucleotide polymorphism (SNP) analysis. The use of MDA in single sperm amplification may open a new era for studies on local recombination rates.

Jiang, Zhengwen; Zhang, Xingqi; Deka, Ranjan; Jin, Li

2005-01-01

299

Effect of different monosaccharides and disaccharides on boar sperm quality after cryopreservation.  

PubMed

The aim of the present study was to evaluate the cryoprotectant effect of different non-permeating sugars for boar sperm. Pooled semen from three boars was used for the experiments. In the first experiment, the sperm quality of boar sperm cryopreserved with an egg-yolk based extender supplemented with different monosaccharides (glucose, galactose or fructose) was compared to a control cryopreserved in lactose-egg yolk extender. In the second experiment, the effect of five disaccharides (lactose, sucrose, lactulose, trehalose or melibiose) on boar sperm cryosurvival was studied. Several sperm quality parameters were assessed by flow cytometry in samples incubated for 30 and 150 min at 37°C after thawing: percentages of sperm with intact plasma membrane (SIPM), sperm presenting high plasma membrane fluidity (HPMF), sperm with intracellular reactive oxygen substances production (IROSP) and apoptotic sperm (AS). In addition, the percentages of total motile (TMS) and progressively motile sperm (PMS) were assessed at the same incubation times with a computer-assisted sperm analysis system. Freezing extenders supplemented with each of the monosaccharide presented smaller cryoprotective effect than the control extender supplemented with lactose (P<0.05). However, from the three monosaccharides tested, glucose provided the best sperm quality after freezing-thawing. With respect to the disaccharides studied, samples frozen with the extender supplemented with lactulose exhibited in general the lowest sperm quality, except for the percentage of capacitated sperm, which was highest (P<0.05) in the samples cryopreserved with the trehalose extender. Our results suggest that disaccharides have higher cryoprotective effect than monosaccharides, although the monosaccharide composition of the disaccharides is also important, since the best results were obtained with those disaccharides presenting glucose in their composition. PMID:22771077

Gómez-Fernández, José; Gómez-Izquierdo, Emilio; Tomás, Cristina; Mocé, Eva; de Mercado, Eduardo

2012-07-01

300

Increasing Information Worker Productivity through Information Work Infrastructure  

Microsoft Academic Search

Deploying high-quality information work infrastructure leads to higher productivity levels of information workers, findings\\u000a from empirical research show. Different types of information workers use different sets of technologies and devices. Knowledge\\u000a workers with a high degree of autonomy depend on mobile and flexible work infrastructure. The OFFICE21® Information Worker’s Workplace supports productive information work.

Udo-ernst Haner; Jörg Kelter; Wilhelm Bauer; Stefan Rief

2009-01-01

301

Effects of Ferulic Acid on Fertile and Asthenozoospermic Infertile Human Sperm Motility, Viability, Lipid Peroxidation, and Cyclic Nucleotides  

Microsoft Academic Search

The capacity of human sperm fertilization principally depends on sperm motility and membrane integrity. Reactive oxygen species, such as superoxide anion and hydrogen peroxide, are known to impair sperm motility and membrane integrity by inducing membrane lipid peroxidation (LPO). Ferulic acid (FA), an effective constituent in various medicinal herbs, has recently been shown to scavenge oxygen free radicals and increase

Rong-Liang Zheng; Hong Zhang

1996-01-01

302

[The sperm quality in young patients before cancer therapy].  

PubMed

In the last years increasing incidence of malignant diseases in young men is observed. Sperm cryopreservation before cancer therapy gives the opportunity for these men to have a child in the future, but it is not know whether pretreatment sperm quality is sufficient to preserve fertility potential after thawing. The aim of this study was to compare the semen parameters (volume, total count, concentration, motility, morphology) in young cancer patients before treatment with healthy men, and examining the differences in sperm quality among patients group. Semen specimens were obtained from 81 patients with different neoplasms (testicular cancer n = 65, others n = 16 (Hodgkin's disease n = 11, lymphoma n = 3, Ewing's sarcoma n = 1, osteosarcoma n = l1). Control group consisted of 43 healthy males at similar age that came to our division as potential sperm donors. The total sperm count, concentration per ml, motility (grade A, B and C) and morphology were significantly lower in the cancer patients compared with normal men (p < 0.05), but still adequate for the future assisted reproductive technologies. Patients with testicular neoplasms had only significantly lower total sperm count and concentration in comparison with other cancer patients (p < 0.05). Our results indicate that routine sperm banking should be offered for men before radio/chemotherapy to preserve future fertility. PMID:15518321

Jedrzejczak, Piotr; Taszarek-Hauke, Grazyna; Korman, Marcin; Kopaczy?ski, Piotr; Pawelczyk, Leszek

2004-01-01

303

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

PubMed Central

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 "sex ratio" 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.

Martin, R H; Spriggs, E; Ko, E; Rademaker, A W

1995-01-01

304

Epididymal secretion of a mouse sperm surface component recognized by a monoclonal antibody.  

PubMed

We have generated a monoclonal antibody directed against an antigenic determinant appearing on the surface of mouse sperm tails during passage through the epididymis (a determinant that we now term sperm maturation antigen number four [SMA 4]). The present study demonstrates that sperm retained in the ductuli efferentes following ligation do not acquire the antigen, suggesting that its appearance is not due to changes intrinsic to the sperm, but that the epididymal environment is required. To examine the role of the epididymis in the appearance of this antigen, sections of unfixed frozen or fixed, paraffin embedded tissue from different regions of the male reproductive tract have been studied by indirect immunofluorescence. Results indicate that the antigen is a secretory product of the epididymal epithelium, produced in a short segment of the distal caput epididymidis. Ligation experiments show that absence of sperm or testicular fluid from the epididymis does not affect production of this antigen. Examination of prepubertal mice indicates that antigen production is age dependent, production beginning in the epididymis in mice between 2 and 4 weeks of age. Indirect immunofluorescence analysis of sections of a variety of tissues and organs shows that the antigen is restricted to sperm and to epithelial cells of the male reproductive tract. Finally, experiments comparing the antibody-induced agglutinability of sperm from the caput epididymidis to that of sperm from the cauda epididymidis gives further evidence that the antigen resides on the sperm surface.U PMID:7044433

Vernon, R B; Muller, C H; Herr, J C; Feuchter, F A; Eddy, E M

1982-04-01

305

Alleviating fertilizer policy constraints to increased fertilizer use and increased food production in West Africa  

Microsoft Academic Search

In sub-Saharan Africa, sustainable economic growth and development, food security, and fair income distribution are possible only if there is sustained growth in agricultural production. The influx of commercially imported or donated foodgrains has helped many governments to maintain a policy of low food prices, usually for the benefit of the vocal urban dwellers. Such practices tend to kill the

F. Makken

1991-01-01

306

Intra-industry trade in intermediate products, pollution and internationally increasing returns  

Microsoft Academic Search

This paper examines the relationship between intra-industry trade in intermediate products, pollution and increasing returns. We develop a two-country model in which production occurs in two stages, final and intermediate good production. Intermediate goods are produced under monopolistic competition and final good production exhibits increasing returns with respect to the number of varieties of intermediates. Pollution occurs in the production

Michael Benarroch; Rolf Weder

2006-01-01

307

Non-viral transfection of goat germline stem cells by nucleofection results in production of transgenic sperm after germ cell transplantation  

PubMed Central

Germline stem cells (GSCs) can be used for large-animal transgenesis, in which GSCs that are genetically manipulated in vitro are transplanted into a recipient testis to generate donor-derived transgenic sperm. The objectives of this study were to explore a non-viral approach for transgene delivery into goat GSCs and to investigate the efficiency of nucleofection in producing transgenic sperm. Four recipient goats received fractionated irradiation at 8 weeks of age to deplete endogenous GSCs. Germ-cell transplantations were performed 8-9 weeks post-irradiation. Donor cells were collected from testes of 9 week-old goats, enriched for GSCs by Staput velocity sedimentation, and transfected by nucleofection with a transgene construct harboring the human growth hormone gene under the control of the goat beta-casein promoter (GBC) and a chicken beta-globin insulator (CBGI) sequence upstream of the promoter. For each recipient, transfected cells from 10 nucleofection reactions were pooled, mixed with non-transfected cells to a total of 1.5×108 cells in 3ml, and transplanted into one testis (n = 4 recipients) by ultrasound-guided cannulation of the rete testis. The second testis of each recipient was removed. Semen was collected starting at 9 months after transplantation for a period of over a year (a total of 62 ejaculates from 4 recipients). Nested genomic PCR for hGH and CBGI sequences demonstrated that 31.3%±12.6% of ejaculates were positive for both hGH and CBGI. This study provides proof-of-concept that non-viral transfection (nucleofection) of primary goat germ cells followed by germ cell transplantation results in transgene transmission to sperm in recipient goats.

Zeng, W.; Tang, Lin; Bondareva, A.; Luo, J.; Megee, S. O.; Modelski, M.; Blash, S.; Melican, D.T.; Destrempes, M.M.; Overton, S.A.; Gavin, W.G.; Ayres, S.; Echelard, Y.; Dobrinski, I.

2011-01-01

308

AN APPROACH TO TILTROTOR WING AEROSERVOELASTIC OPTIMIZATION THROUGH INCREASED PRODUCTIVITY  

Microsoft Academic Search

The paper describes one way to approach the multidisciplinary task of optimizing a tiltrotor wing structure which is equipped with an active flutter suppression system. Objective function is a productivity index, as a measure for aircraft cost-effectiveness. Short digress is held on the characteristics of the tiltrotor's dynamic system and its aeroelastic behavior. Contributing analyses (CA's) for calculating aircraft performance,

Martin Stettner; Daniel P. Schrage

1992-01-01

309

Secondary sexual characters and sperm traits in coho salmon Oncorhynchus kisutch  

Microsoft Academic Search

ABSTRACT The sperm,competition,hypothesis predicts that males likely to occupy,disfavored spawning positions, as indicated by reduced expression of secondary sexual characters, would allocate more,resources to sperm production and velocity to compensate,for relatively poor access to spawning females. To test these predictions, body size metrics and red abdominal spawning colouration were examined,in relation to sperm related metrics in coho salmon,(Oncorhynchus kisutch). Males

T. E. Pitcher; S. M. Doucet; J.-M. J. Beausoleil; D. Hanley

2009-01-01

310

Alleviating fertilizer policy constraints to increased fertilizer use and increased food production in West Africa  

Microsoft Academic Search

\\u000a In sub-Saharan Africa, sustainable economic growth and development, food security, and fair income distribution are possible\\u000a only if there is sustained growth in agricultural production. The influx of commercially imported or donated foodgrains has\\u000a helped many governments to maintain a policy of low food prices, usually for the benefit of the vocal urban dwellers. Such\\u000a practices tend to kill the

F. Makken

311

The effects of male age on sperm analysis by motile sperm organelle morphology examination (MSOME)  

PubMed Central

Background This study aimed to investigate the influence of age on sperm quality, as analysed by motile sperm organelle morphology examination (MSOME). Methods Semen samples were collected from 975 men undergoing evaluation or treatment for infertility. Sperm cells were evaluated at 8400× magnification using an inverted microscope equipped with Nomarski (differential interference contrast) optics. Two forms of spermatozoa were considered: normal spermatozoa and spermatozoa with large nuclear vacuoles (LNV, defined as vacuoles occupying > 50% of the sperm nuclear area). At least 200 spermatozoa per sample were evaluated, and the percentages of normal and LNV spermatozoa were determined. The subjects were divided into three groups according to age: Group I, less than or equal to 35 years; Group II, 36-40 years; and Group III, greater than or equal to 41 years. Results There was no difference in the percentages of normal sperm between the two younger (I and II) groups (P >0.05). The percentage of normal sperm in the older group (III) was significantly lower than that in the younger (I and II) groups (P < 0.05). There was no difference in the percentage of LNV spermatozoa between the younger (I and II) groups (P >0.05). The percentage of LNV spermatozoa was significantly higher in the older group (III) than in the younger (I and II) groups (P < 0.05). Regression analysis demonstrated a significant decrease in the incidence of normal sperm with increasing age (P < 0.05; r = -0.10). However, there was a significant positive correlation between the percentage of spermatozoa with LNV and male age (P < 0.05, r = 0.10). Conclusion The results demonstrated a consistent decline in semen quality, as reflected by morphological evaluation by MSOME, with increased age. Considering the relationship between nuclear vacuoles and DNA damage, these age-related changes predict that increased paternal age should be associated with unsuccessful or abnormal pregnancy as a consequence of fertilisation with damaged spermatozoa. Given that sperm nuclear vacuoles can be evaluated more precisely at high magnification, these results support the routine use of MSOME for ICSI as a criterion for semen analysis.

2012-01-01

312

Effect of procarbazine on sperm morphology in syrian hamsters  

Microsoft Academic Search

The effect of procarbazine, an antineoplastic drug, on the reproductive system of male Syrian hamsters was studied. Exposure to procarbazine (5 daily doses ranging from 20 to 500 mg\\/kg body weight) resulted in 5? to 7.5?fold increase in sperm abnormalities, diminished sperm counts, and smaller testes within 4 wk. Transmission electron micrographs showed severe damage to the acrosomal plasma membrane

Harpal Singh; Thomas Kozel; Servon Jackson

1989-01-01

313

Potential strategies for increasing drug-discovery productivity.  

PubMed

The productivity challenge facing the pharmaceutical industry is well documented. Strategies to improve productivity have mainly focused on enhancing efficiency, such as the application of Lean Six Sigma process improvement methods and the introduction of modeling and simulation in place of 'wet' experiments. While these strategies have their benefits, the real challenge is to improve effectiveness by reducing clinical failure rates. We advocate redesigning the screening cascade to identify and optimize novel compounds with improved efficacy against disease, not just with improved potency against the target. There should be greater use of disease-relevant phenotypic screens in conjunction with target-based assays to drive medicinal chemistry optimization. An opportunistic approach to polypharmacology is recommended. There should also be more emphasis on optimization of the molecular mechanism of action incorporating understanding of binding kinetics, consideration of covalent drug strategies and targeting allosteric modulators. PMID:24649955

Cumming, John G; Finlay, M Raymond V; Giordanetto, Fabrizio; Hemmerling, Martin; Lister, Troy; Sanganee, Hitesh; Waring, Michael J

2014-04-01

314

Increasing Cropping System Diversity Balances Productivity, Profitability and Environmental Health  

PubMed Central

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 large negative impacts on the environment. We hypothesized that cropping system diversification would promote ecosystem services that would supplement, and eventually displace, synthetic external inputs used to maintain crop productivity. To test this, we conducted a field study from 2003–2011 in Iowa that included three contrasting systems varying in length of crop sequence and inputs. We compared a conventionally managed 2-yr rotation (maize-soybean) that received fertilizers and herbicides at rates comparable to those used on nearby farms with two more diverse cropping systems: a 3-yr rotation (maize-soybean-small grain + red clover) and a 4-yr rotation (maize-soybean-small grain + alfalfa-alfalfa) managed with lower synthetic N fertilizer and herbicide inputs and periodic applications of cattle manure. Grain yields, mass of harvested products, and profit in the more diverse systems were similar to, or greater than, those in the conventional system, despite reductions of agrichemical inputs. Weeds were suppressed effectively in all systems, but freshwater toxicity of the more diverse systems was two orders of magnitude lower than in the conventional system. Results of our study indicate that more diverse cropping systems can use small amounts of synthetic agrichemical inputs as powerful tools with which to tune, rather than drive, agroecosystem performance, while meeting or exceeding the performance of less diverse systems.

Davis, Adam S.; Hill, Jason D.; Chase, Craig A.; Johanns, Ann M.; Liebman, Matt

2012-01-01

315

Increasing pharmacy productivity by expanding the role of pharmacy technicians.  

PubMed

Efforts to meet growing clinical and distributive demands without increasing pharmacy staff are described. Real and expected increases in demands for services led pharmacists at a cancer center to seek ways of accommodating those demands within budgetary limits. Growth in the distributive workload was interfering with clinical consultation work. Research studies by the medical staff were resulting in complex dosage calculations and time-consuming compounding. Increasing requests for clinical services had to be met without compromising distributive services and teaching responsibilities and without raising costs. A plan of action was approved that included the use of a written test and a training manual to allow the hiring and retaining of skilled pharmacy technicians qualified to assume greater responsibilities. Technicians were assigned to enter drug orders into the computer, check other technicians, and dispense certain drugs. Greater use was made of commercially prepared i.v. solutions, and the floor stock was expanded. A comprehensive quality control program was concurrently put in place. The larger role for technicians not only enabled the pharmacy department to increase its distributive workload dramatically but reduced pharmacy medication errors and provided more time for clinical pharmacy practice. The number of pharmacist and technician full-time equivalents increased by only 1.5 in each category between 1985 and 1990. By making more use of pharmacy technicians, a pharmacy department was able to meet escalating demands for services with only a minor increase in personnel. PMID:1570872

Kalman, M K; Witkowski, D E; Ogawa, G S

1992-01-01

316

Persistent impairment of testicular histology and sperm motility in adult rats treated with Cisplatin at peri-puberty.  

PubMed

Cisplatin is one of the most widely used and effective chemotherapeutic agents for the treatment of several human malignancies. This study evaluated the effects of peri-pubertal cisplatin administration on several reproductive end-points and the reversibility of these effects in adulthood. Peri-pubertal Wistar male rats (45 days old) were divided into two groups: control (saline 0.9%) and cisplatin (1 mg/kg/day, 5 days/week, for 3 weeks, i.p.). The study was conducted in two steps and evaluations were performed at ages of 66 (post-pubertal age) and 140 (adult age) days on: (i) organ weights, serum gonadotropins and testosterone levels, sperm counts, motility and morphology, testicular histomorphometry, spermatogenesis kinetics, Sertoli cell number and in situ detection of apoptotic germ cells and (ii) sexual behaviour, fertility and intratesticular testosterone. At the end of cisplatin therapy, rats showed reductions in sperm production and reserves, sperm with progressive movement, tubular diameter, intratesticular testosterone and fertility potential, but increased numbers of TUNEL-positive seminiferous tubules, immotile sperm and pre-implantation losses compared with control. Moreover, cisplatin-treated post-pubertal rats displayed impaired testicular histopathology and sexual behaviour. Serum gonadotropins and testosterone levels, sperm morphology, spermatogenesis kinetics and Sertoli cell number were comparable between experimental groups at both ages. Alterations found in post-puberty were recovered at adulthood, except for sperm motility and damage to testicular histology. The persistence of these cisplatin effects, despite the unaltered fertility after natural mating in rats, may have implications for reproductive function of young boys undergoing cancer therapy, given the lower reproductive efficiency in human beings compared with rats. PMID:21410649

Favareto, Ana Paula Alves; Fernandez, Carla Dal Bianco; da Silva, Daniela Alessandra Fossato; Anselmo-Franci, Janete Aparecida; Kempinas, Wilma De Grava

2011-08-01

317

Golbal Economic and Environmental Impacts of Increased Bioenergy Production  

SciTech Connect

The project had three main objectives: to build and incorporate an explicit biomass energy sector within the GTAP analytical framework and data base; to provide an analysis of the impact of renewable fuel standards and other policies in the U.S. and E.U, as well as alternative biofuel policies in other parts of the world, on changes in production, prices, consumption, trade and poverty; and to evaluate environmental impacts of alternative policies for bioenergy development. Progress and outputs related to each objective are reported.

Wallace Tyner

2012-05-30

318

Stochastic Models of Sperm Motility.  

National Technical Information Service (NTIS)

Stochastic models for sperm motion are investigated. The intention is to use these models as an aid to fertility diagnosis. The sperm track data are modeled as a smooth mean track plus a two-dimensional residual which divides naturally into along-track an...

B. J. McCabe B. Belkin D. H. Wagner K. M. Sommar

1987-01-01

319

[Epigenetics of the sperm cell].  

PubMed

In addition to genetic information, the spermatozoon carries another type of information, named epigenetic, which is not associated with variations of the DNA sequence. In somatic cells, it is now generally admitted that epigenetic information is not only regulated by DNA methylation but also involves modifications of the genome structure, or epigenome. During male germ cell maturation, the epigenome is globally re-organized, since most histones, which are associated to DNA in somatic cells, are removed and replaced by sperm specific nuclear proteins, the protamines, responsible for the tight compaction of the sperm DNA. However, a small proportion of histones, and probably other proteins, are retained within the sperm nucleus, and the structure of the sperm genome is actually heterogeneous. This heterogeneity of the sperm epigenome could support an epigenetic information, transmitted to the embryo, which could be crucial for its development. Although it is nowadays possible to appreciate the global structure of the sperm genome, the precise constitution of the sperm epigenome remains unknown. In particular, very recent data suggest that specific regions of the genome could be associated with particular proteins and define specific structures. This structural partitioning of the sperm genome could convey important epigenetic information, crucial for the embryo development. PMID:16949851

Rousseaux, S; Faure, A-K; Thévenon, J; Escoffier, E; Lestrat, C; Govin, J; Hennebicq, S; Sèle, B; Caron, C; Khochbin, S

2006-09-01

320

Sperm segregation patterns by fluorescence in situ hybridization studies of a 46,XY,t(2;6) heterozygote giving rise to a rare triploid product of conception with a 69,XXY,t(2;6)(p12;q24)der(6)t(2;6)(p12;q24)pat karyotype.  

PubMed

A blighted ovum diagnosed initially by ultrasound was determined to be a partial hydatidiform mole with a 69,XXY,t(2;6)(p12;q24)der(6)t(2;6)(p12;q24)pat karyotype by cytogenetic analysis. The triploid state arose through dispermy in which both spermatozoa carried rearranged chromosomes, one carrying a balanced translocation through alternate segregation and the other an unbalanced derivative chromosome 6 through adjacent 1 segregation. Segregation analysis of 7,000 spermatozoa from the father was performed with a three-color fluorescence in situ hybridization (FISH) protocol using alpha-satellite 6, telomeric 2p, and telomeric 6q probes. Segregation frequencies of normal and balanced products (alternate segregation), adjacent 1, adjacent 2, and 3:1 were 49.9%, 42.4%, 2.5%, and 4.2%, respectively. The high percentage of alternate segregation is consistent with the knowledge of their preferential outcome. However, the high incidence of adjacent 1 sperm highlights the abnormality risk. Alternate and adjacent 1 segregations (92.3%) accounted for the observed rearranged chromosomes in the triploid. The most viable imbalanced combination would be the one carrying the der(6) chromosome, but since the unbalanced segment comprises 3.6% of the haploid autosomal length (HAL), no risk of a viable imbalanced offspring is indicated. However, an increased likelihood of recurrent miscarriages is likely, and this is confirmed by the couple's two earlier miscarriages. Sperm segregation patterns of translocation carriers determined by FISH can help in ascertaining expected and unexpected karyotypes. The high frequency of adjacent 1 products shows that the presence of the additional derivative chromosome in the partial mole, though rare in occurrence, should be less surprising. PMID:12567417

Lim, A S T; Lim, T H; Kee, S K; Chieng, R; Tay, S K

2003-03-01

321

Increased Alberta bitumen production results in prorationing of light oil production  

SciTech Connect

During January to May 1986, shut-in production of light oil in Alberta averaged 109,000 barrels per day. The peak month was April with a shut-in of 164,000 barrels per day. The cause of the shut-in is insufficient pipeline delivery capacity. Both the Interprovincial and TransMountain systems have been operating at full capacity since November 1985. The Rangeland system has also been utilized to its capacity in late spring. This paper discusses the history of the Alberta Proration Plan dating from 1950, the operation of the plan during the recent past years, and the resulting effects of an increase in bitumen production on the transport capacity for light oil.

Not Available

1986-09-01

322

A mutant gene that increases gibberellin production in Brassica  

Microsoft Academic Search

A single gene mutant (elongated internode (ein\\/ein)) with accelerated shoot elongation was identified from a rapid cycling line of Brassica rapa. Relative to normal plants, mutant plants had slightly accelerated floral development, greater stem dry weights, and particularly, increased internode and inflorescence elongation. The application of the triazole plant growth retardant, paclobutrazol, inhibited shoot elongation, returning ein to a more

S. B. Rood; P. H. Williams; D. Pearce; R. P. Pharis; Noboru Murofushi; L. N. Mander

1990-01-01

323

The increasing importance of herbicides in worldwide crop production.  

PubMed

Herbicide use is increasingly being adopted around the world. Many developing countries (India, China, Bangladesh) are facing shortages of workers to hand weed fields as millions of people move from rural to urban areas. In these countries, herbicides are far cheaper and more readily available than labor for hand weeding. History shows that in industrializing countries in the past, including the United States, Germany, Japan and South Korea, the same phenomenon has occurred-as workers have left agriculture, herbicides have been adopted. It is inevitable that herbicide use will increase in sub-Saharan Africa, not only because millions of people are leaving rural areas, creating shortages of hand weeders, but also because of the need to increase crop yields. Hand weeding has never been a very efficient method of weed control-often performed too late and not frequently enough. Uncontrolled weeds have been a major cause of low crop yields in sub-Saharan Africa for a long time. In many parts of the world, herbicides are being increasingly used to replace tillage in order to improve environmental conditions. In comparison with tillage, herbicide use reduces erosion, fuel use, greenhouse gas emissions and nutrient run-off and conserves water. PMID:23794176

Gianessi, Leonard P

2013-10-01

324

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)

Nabavi, Narges; Todehdehghan, Fatemeh; Shiravi, Abdollhossein

2013-01-01

325

Increased olefins production via recovery of refinery gas hydrocarbons  

SciTech Connect

In the process of catalytically cracking heavy petroleum fractions to make gasoline and light fuel oil, by-product waste gases are also generated. The waste gases, normally used as fuel, are themselves rich sources of ethylene, propylene and other light hydrocarbons which can be recovered inexpensively via a cryogenic dephlegmator process. This gas separation technique is exploited in a system, in operation since spring of 1987, which reclaims C/sub 2/+ hydrocarbons from a refinery gas. The reclamation process bolsters production in a nearby ethylene plant. Causing no disruption of ethylene plant operations, the cryogenic hydrocarbon recovery system functions smoothly with existing systems. The dephlegmation unit operation melds distillation and heat transfer processes in a single easily-controlled step which boosts the hydrocarbon purity and recovery above the levels profitably achievable with conventional cryogenic separation techniques. Very attractive operating economics follow from high purity, high recovery, and high energy efficiency. This paper discusses process concepts, economic benefits, plant operation, and early performance results.

Bernhard, D.P.; Rowles, H.C.; Moss, J.A.; Pickering, J.L. Jr.

1988-01-01

326

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

327

Sperm motion analysis  

NASA Astrophysics Data System (ADS)

This paper presents a computerized technique for quantitative analysis of the movement characteristics of spermatozoa. Stored video images of spermatozoa are digitized at a fixed time interval. The digital images are stored as a sequence of frames in a microcomputer. The analysis of the sequence comprises two main tasks: finding the location of the centroid for each sperm and tracking them over the entire sequences. Information from the motion of each moving cell will be used for tracking. Experimental results are presented to show the merits of the proposed algorithm for tracking.

Salari, Valiollah

1991-07-01

328

Increased root production in soybeans grown under space flight conditions.  

NASA Astrophysics Data System (ADS)

The GENEX ({Gen}e {Ex}pression) spaceflight experiment (flown on STS-87) was developed to investigate whether direct and/or indirect effects of microgravity are perceived as an external stimulus for soybean seedling response. Protocols were designed to optimize root and shoot formation, gas exchange and moisture uniformity. Six surface sterilized soybean seeds (Glycine max cv McCall) were inserted into each of 32 autoclaved plastic seed growth pouches containing an inner germination paper sleeve (for a total of 192 seeds). The pouches were stowed within a mid-deck locker until Mission Flight Day 10, at which time an astronaut added water to each pouch (thereby initiating the process of seed germination on-orbit), and subsequently transferred them to four passive, light-tight aluminum canisters called BRIC-60s (Biological Research In Canisters). We report here on the morphological characteristics of: (1) the recovered flight material, (2) the corresponding ground control population, plus (3) additional controls grown on the ground under clinostat conditions. No significant growth differences were found between the flight, ground control and clinorotated treatments for either the cotyledons or hypocotyls. There were, however, significantly longer primary roots produced in the flight population relative to the ground control population, which in turn had significantly longer primary roots than the clinorotated population. This same pattern was observed relative to the production of lateral roots (flight > control > clinorotated). Taken together with previous literature reports, we believe that there is now sufficient evidence to conclude that plants grown under conditions of microgravity will generally exhibit enhanced root production relative to their ground control counterparts. The mechanism underlying this phenomenon is open to speculation. Funded under NASA Contract NAS10-12180.

Levine, H. G.; Piastuch, W. C.

329

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.

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

2013-01-01

330

Evaluation of sperm selection procedure based on hyaluronic acid binding ability on ICSI outcome  

PubMed Central

Purpose To compare the efficiency of routine sperm selection method with HA-selection procedure for fertilization rate, embryo development, implantation and pregnancy rates as well as evaluating the relationship between HA-binding ability with sperm protamine deficiency and DNA fragmentation. Methods Semen samples were obtained from the 50 couples undergoing ICSI. The percentage of fertilization rate, cleavage and quality of embryos compared between two procedures (routine sperm selection and HA-binding selection). The semen samples were assessed for DNA fragmentation and protamine deficiency by sperm chromatin dispersion (SCD) test and Chromomycin A3 (CMA3) staining, respectively. Results A significant inverse correlation was observed between percentage of HA binding with protamine deficiency, DNA fragmentation and abnormal sperm morphology (P?sperm selection procedure had significantly higher fertilization rate (P?increased. Conclusion The results suggest that normal sperm have higher chance to bind HA and therefore, HA sperm selection procedure may select sperm with normal protamine content and low DNA fragmentation, but to confirm the effect of HA sperm selection on the ICSI outcome requires further studies.

Razavi, S.; Vahdati, A. A.; Fathi, F.; Tavalaee, M.

2008-01-01

331

Effects of progesterone on sperm motility in fathead minnow (Pimephales promelas).  

PubMed

The steroid hormone progesterone (P4) is found at relatively high concentrations (?300 ng/L) in association with concentrated animal feeding operations (CAFOs). In an effort to better understand the potential endocrine disrupting effects of P4 in male fish, computer assisted sperm analysis (CASA) was used to evaluate the effects of this steroid on sperm motility in the fathead minnow (Pimephales promelas). The rationale for focusing on sperm motility is that certain progestins have been shown to bind to surface membrane receptors on fish spermatozoa and increase sperm swimming velocity. It was hypothesized, therefore, that sperm swimming velocity might be a useful indicator of progestin exposure in fish. Adult male fathead minnows (ages 6-12 months) were exposed to environmentally relevant doses of P4, both longer-term (1 week, in vivo exposure) and short-term (minutes, in vitro exposure). Sperm were then video recorded and analyzed by CASA. When fathead minnows were continuously exposed for 1 week to low levels of progesterone in vivo there was a significant dose-dependent reduction in sperm motility. There was no effect of short-term P4 exposure on fathead minnow sperm swimming characteristics. Additional research is required to elucidate the mechanism by which progesterone alters sperm swimming in the fathead minnow. With further validation, the fathead minnow sperm motility assay may be a useful tool to rapidly screen for endocrine disrupting chemicals in the aquatic environment. PMID:21569753

Murack, Patrick J; Parrish, John; Barry, Terence P

2011-07-01

332

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

333

Sperm DNA fragmentation in boars is delayed or abolished by using sperm extenders  

Microsoft Academic Search

The semen quality of seven young adult boars was assessed for percentages of sperm motility, normal acrosomes, abnormal sperm, cells positive to sHOST (short Hipoosmotic Swelling Test), HPNA cells (sHOST Positive with Normal Acrosome cells) and the percentage of sperm heads, which exhibited DNA fragmentation using the Sperm Chromatin Dispersion test (SCD). These parameters were analysed in sperm samples both

Begoña Pérez-Llano; María Enciso; Pedro García-Casado; Rubén Sala; Jaime Gosálvez

2006-01-01

334

Liposomes for cryopreservation of bovine sperm.  

PubMed

In this study, the effect of various unilamellar liposomes on cryopreservation of bovine spermatozoa has been investigated. Liposomes were composed of saturated lipids with various acyl chain lengths: DSPC (18:0), DPPC (16:0), DMPC (14:0), or DLPC (12:0). Alternatively, liposomes were prepared using unsaturated egg phosphatidylcholine (EPC) or DOPC (18:1, neutral), alone or in combination with lipids with various head groups: DOPS (negatively charged), DOPG (negatively charged), and DOPE (neutral). Fourier transform infrared spectroscopy studies showed that bovine sperm membranes display a gradual phase transition from 10 to 24 (o)C. Phase transition temperatures of the liposomes varied from -20 to +53 (o)C. Sperm was incubated in the presence of liposomes for either 6 or 24 h at 4 °C prior to freezing. Postfreeze survival rates were determined based on the percentage of progressively motile cells as well as the percentage of acrosome- and plasma membrane-intact cells. With DOPC liposomes a postthaw progressive motility of 43% was obtained compared with 59% using standard egg yolk freezing extender. Postthaw progressive motility increased up to 52% using DOPC:DOPG (9:1) liposomes, whereas DOPC:DOPS or DOPC:DOPE liposomes did not increase survival compared with DOPC liposomes. Among the saturated lipids, only DMPC was found to increase cryosurvival, up to 44% based on progressive motility. DLPC liposomes caused a complete loss in cell viability, already prior to freezing, whereas DPPC and DSPC liposomes neither positively nor negatively affected cryosurvival. Taken together, the higher postthaw survival obtained with DOPC:DOPG liposomes as compared with DOPC liposomes can likely be attributed to increased liposome-sperm interactions between the charged phosphatidylglycerol groups and charged regions in the sperm membranes. Interestingly, the lipid phase state of the liposomes during preincubation is not the decisive factor for their cryoprotective action. PMID:21820724

Röpke, T; Oldenhof, H; Leiding, C; Sieme, H; Bollwein, H; Wolkers, W F

2011-11-01

335

Effects of tributyltin on epididymal function and sperm maturation in mice  

Microsoft Academic Search

The effects of tributyltin (TBT) on sperm parameters and epididymal function were investigated following oral doses of 0.5, 5 and 50?g\\/kg every 3 days for 45 days to male KM mouse. The TBT-treated groups showed a significant decrease in sperm counts and a significant increase in sperm abnormality both in a dose-dependent manner. The expression of matrilysin (MMP7) transcript in

Feihuan Yan; Yufang Chen; Zhenghong Zuo; Yixin Chen; Zengming Yang; Chonggang Wang

2009-01-01

336

Protamine levels vary between individual sperm cells of infertile human males and correlate with viability and DNA integrity.  

PubMed

Sperm protamine deficiency has been associated with human male infertility. However, most studies have adopted a global approach to assessing sperm protamine levels. Thus, it is not known whether sperm cells from individual human males possess variations in protamine protein content. The objectives of this study were to evaluate variations in protamine-1 (P1) and protamine-2 (P2) content between individual sperm cells of fertile and infertile men and to correlate DNA integrity and sperm cell viability with protamine levels in individual sperm cells. The semen samples of fertile and infertile men were evaluated globally for protamine protein content using nuclear protein extraction, gel electrophoresis, and densitometry analysis. Individual sperm cell P1 and P2 levels were assessed using immunofluorescence microscopy in conjunction with automated image analysis. The terminal transferase dUTP nick end labeling (TUNEL) assay was performed simultaneously with protamine immunostaining to assess the relationship between protamine levels and DNA integrity in individual spermatozoa. Additionally, the relationship between sperm cell viability and protamine levels was assessed via viability staining concomitant with protamine staining. The protamine fluorescence data demonstrate significant variations in protamine content within individual sperm cells of human males. Overall population-based measures of DNA integrity and sperm cell viability correlate significantly with population-based measurements of protamine levels. The data also demonstrate individual sperm cells displaying the lowest protamine levels display diminished viability and increased sperm cell susceptibility to DNA damage. PMID:16870950

Aoki, Vincent W; Emery, Benjamin R; Liu, Lihua; Carrell, Douglas T

2006-01-01

337

Development of methods for cryopreservation of rooster sperm from the endangered breed "Gallina Valenciana de Chulilla" using low glycerol concentrations.  

PubMed

Glycerol (11%; v:v) is the cryoprotectant most often used for the cryopreservation of rooster sperm. However, chicken breeds differ in the resistance of their sperm to the cryopreservation process and endangered or local breeds usually present low fertilizing ability when conventional sperm cryopreservation protocols are used. The objective of this study was to optimize the protocol for the cryopreservation of the sperm from the endangered breed "Gallina Valenciana de Chulilla". For this purpose, 10 pools of semen from 43 roosters of this breed were cryopreserved using 8%, 7%, 6%, or 4% glycerol, and the sperm quality was determined immediately after thawing and in the insemination doses. Lohmann Brown Classic laying hens (n = 40) were used for the insemination trials. The sperm quality after cryopreservation progressively decreased as the glycerol concentration was reduced (P < 0.01); samples frozen using 4% glycerol exhibited the lowest quality (38% total motile sperm and 49% live sperm), and samples frozen using 8% glycerol exhibited the highest quality (67% total motile sperm and 66% live sperm). These differences were also observed after the glycerol was removed (P < 0.01). However, the sperm fertilizing ability was similar for all the treatments (23%-30% fertilized eggs), and increased as the glycerol concentration decreased. In conclusion, semen from roosters frozen using 4% glycerol exhibited lower sperm quality but similar fertilizing ability compared with samples processed using higher glycerol concentrations. These results may provide useful information for developing cryopreservation protocols for other breeds. PMID:24629594

Blanch, E; Tomás, C; Casares, L; Gómez, E A; Sansano, S; Giménez, I; Mocé, E

2014-06-01

338

Sperm Competition Games: Raffles and Roles  

Microsoft Academic Search

Evolutionary games in which two males mate with the same female are examined by using an evolutionarily stable strategy (ESS) approach. These prospective models of competitive ejaculation seek ESS sperm numbers for cases when sperm competition obeys the `raffle principle'. In a `fair raffle', each male's fertilization probability equals his sperm number divided by the total sperm number in the

G. A. Parker

1990-01-01

339

Sexual colouration and sperm traits in guppies  

Microsoft Academic Search

The relationships among the area, hue, saturation and brightness of orange colouration and sperm traits in the guppy Poecilia reticulata were investigated. Males with greater areas of orange colouration had significantly larger sperm loads, more motile sperm and longer sperm relative to males with relatively little orange colouration. Males with greater areas of orange colouration did not possess more viable

T. E. Pitcher; F. H. Rodd; L. Rowe

2007-01-01

340

Role of glucocorticoids in increased muscle glutamine production in starvation  

NASA Technical Reports Server (NTRS)

The role of glucocorticoids in the synthesis of muscle glutamine during starvation was investigated in adrenalectomized fasted rats injected with cortisol (1 mg/100 g body weight). It was found that administration of cortisol in vivo increased (compared to nontreated starved adrenalectomized controls) the glutamine/glutamate ratio and the activity of glutamine synthetase in the diaphragm and the extensor digitorum muscles, and that these effects were abolished by prior treatment with actinomycin D or proflavine. The results obtained in in vitro experiments, using fresh-frozen soleus, extensor digitorum longus, and diaphragm muscle preparations, supported the in vivo indications of the cortisol-enhanced glutamine synthesis and protein turnover in starved adrenalectomized animals.

Tischler, Marc E.; Henriksen, Erik J.; Cook, Paul H.

1988-01-01

341

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

342

Sperm status and DNA dose play key roles in sperm/ICSI-mediated gene transfer in caprine.  

PubMed

In relation to the growing recent interest in the establishment of sperm-mediated gene transfer (SMGT) technology as a convenient and effective method for the simple production of transgenic animals, in this study the possibility of using SMGT to produce transgenic caprine embryos was investigated for the first time. Buck sperm were directly incubated with different concentrations (0-500 ng) of pcDNA/his/Lac-Z plasmid and used for IVF or ICSI. Sperm used for ICSI were categorized into motile or live-immotile group before being injected into oocytes. In a separate experiment, dead sperm prepared by repeated freezing/thawing were used for DNA-incubation before ICSI. Sham injection was carried out by intracytoplasmic injection of approximately the same volume of media containing different doses of DNA using an ICSI needle. Transgene expression and transmission were detected by X-Gal staining and PCR analysis of developed embryos, respectively. A reasonable blastocyst rate was observed in all the groups. Only embryos in the sham group were negative for transgene transmission. Transgene expression was completely dependent on the delivery technique and status of sperm, and was only observed in the live-immotile and dead ICSI groups. The results of this study showed that the technique (IVF vs. ICSI vs. sham injection), sperm status (motile vs. live-immotile vs. dead) and to some extent DNA concentration affect embryo development, transgene transmission and expression. PMID:20737474

Shadanloo, Farshad; Najafi, Mohammad Hasan; Hosseini, Sayed Morteza; Hajian, Mehdi; Forouzanfar, Mohsen; Ghaedi, Kamran; Abedi, Parvaneh; Ostadhosseini, Somaye; Hosseini, Laleh; Eskandari-Nasab, Morad-Pasha; Esfahani, Mohammad Hossein Nasr

2010-10-01

343

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

344

The BSA-induced Ca(2+) influx during sperm capacitation is CATSPER channel-dependent  

PubMed Central

Background Serum albumin is a key component in mammalian sperm capacitation, a functional maturation process by which sperm become competent to fertilize oocytes. Capacitation is accompanied by several cellular and molecular changes including an increased tyrosine phosphorylation of sperm proteins and a development of hyperactivated sperm motility. Both of these processes require extracellular calcium, but how calcium enters sperm during capacitation is not well understood. Methods BSA-induced changes in intracellular calcium concentration were studied using Fluo-4 and Fura-2 calcium imaging with wild-type and Catsper1 knockout mouse sperm. Results We found that the fast phase of the BSA-induced rises in intracellular calcium concentration was absent in the Catsper1 knockout sperm and could be restored by an EGFP-CATSPER1 fusion protein. The calcium concentration increases were independent of G-proteins and phospholipase C but could be partially inhibited when intracellular pH was clamped. The changes started in the principal piece and propagated toward the sperm head. Conclusion We conclude that the initial phase of the increases in intracellular calcium concentration induced by BSA requires the CATSPER channel, but not the voltage-gated calcium channel. Our findings identify the molecular conduit responsible for the calcium entry required for the sperm motility changes that occur during capacitation.

Xia, Jingsheng; Ren, Dejian

2009-01-01

345

A mutant gene that increases gibberellin production in Brassica  

SciTech Connect

A single gene mutant (elongated internode (ein/ein)) with accelerated shoot elongation was identified from a rapid cycling line of Brassica rapa. Relative to normal plants, mutant plants had slightly accelerated floral development, greater stem dry weights, and particularly, increased internode and inflorescence elongation. The application of the triazole plant growth retardant, paclobutrazol, inhibited shoot elongation, returning ein to a more normal phenotype. Conversely, exogenous gibberellin A{sub 3} (GA{sub 3}) can convert normal genotypes to a phenotype resembling ein. The content of endogenous GA{sub 1} and GA{sub 3} were estimated by gas chromatography-selected ion monitoring using ({sup 2}H)GA{sub 1} as a quantitative internal standard and at day 14 were 1.5- and 12.1-fold higher per stem, respectively, in ein than in normal plants, although GA concentrations were more similar. The endogenous levels of GA{sub 20} and GA{sub 1}, and the rate of GA{sub 19} metabolism were simultaneously analyzed. Levels of GA{sub 1} and GA{sub 20} were 4.6- and 12.9-fold higher, respectively, and conversions to GA{sub 20} and GA{sub 1} were 8.3 and 1.3 times faster in ein than normal plants. Confirming the enhanced rate of GA{sub 1} biosynthesis in ein, the conversion of ({sup 3}H)GA{sub 20} to ({sup 3}H) GA{sub 1} was also faster in ein than in the normal genotype. Thus, the ein allele results in accelerated GA{sub 1} biosynthesis and an elevated content of endogenous GAs, including the dihydroxylated GAs A{sub 1} and A{sub 3}.

Rood, S.B. (Univ. of Lethbridge, Alberta (Canada)); Williams, P.H. (Univ. of Wisconsin, Madison (USA)); Pearce, D.; Pharis, R.P. (Univ. of Calgary, Alberta (Canada)); Murofushi, Noboru (Univ. of Tokyo (Japan)); Mander, L.N. (Australian National Univ., Canberra (Australia))

1990-07-01

346

Robotic ICSI (intracytoplasmic sperm injection).  

PubMed

This paper is the first report of robotic intracytoplasmic sperm injection (ICSI). ICSI is a clinical procedure performed worldwide in fertility clinics, requiring pick-up of a single sperm and insertion of it into an oocyte (i.e., egg cell). Since its invention 20 years ago, ICSI has been conducted manually by a handful of highly skilled embryologists; however, success rates vary significantly among clinics due to poor reproducibility and inconsistency across operators. We leverage our work in robotic cell injection to realize robotic ICSI and aim ultimately, to standardize how clinical ICSI is performed. This paper presents some of the technical aspects of our robotic ICSI system, including a cell holding device, motion control, and computer vision algorithms. The system performs visual tracking of single sperm, robotic immobilization of sperm, aspiration of sperm with picoliter volume, and insertion of sperm into an oocyte with a high degree of reproducibility. The system requires minimal human involvement (requiring only a few computer mouse clicks), and is human operator skill independent. Using the hamster oocyte-human sperm model in preliminary trials, the robotic system demonstrated a high success rate of 90.0% and survival rate of 90.7% (n=120). PMID:21521663

Lu, Zhe; Zhang, Xuping; Leung, Clement; Esfandiari, Navid; Casper, Robert F; Sun, Yu

2011-07-01

347

DNA integrity is compromised in protamine-deficient human sperm.  

PubMed

The objective of this study was to examine the relationship between DNA integrity and protamines in human sperm. One hundred forty-nine male infertility patients were included in an Institutional Review Board-approved study. Sperm were evaluated for DNA fragmentation using the DNA Integrity Assay, a test equivalent to the sperm chromatin structure assay (SCSA). Additionally, nuclear proteins were extracted and the protamine-1/protamine-2 ratio (P1/P2), protamine-1 (P1), protamine-2 (P2), and total protamine concentrations were evaluated. We identified 37 patients with abnormally low P1/P2 ratios, 99 patients with normal P1/P2 ratios, and 13 patients with abnormally high P1/P2 ratios. DNA fragmentation was significantly elevated in patients with low P1/P2 ratios (37.1 +/- 6.02) vs those with normal and high P1/P2 ratios (26.7 +/- 1.9 and 23.8 +/- 3.2, respectively; P < .05) and was inversely correlated with the P1/P2 ratio (R(s) -0.18, P < .05), P1 concentration (R(s) -0.29, P < .001), P2 concentration (R(s) - 0.24, P < .005), and total protamine concentration (R(s) -0.28, P < .001). Furthermore, chi2 analysis revealed a significant increase in the incidence of marked DNA fragmentation in patients with diminished levels of either P1 or P2. The present study is the first to report that human sperm protamine content is significantly related to DNA fragmentation. In particular, sperm P1 and P2 concentrations inversely correlate with DNA fragmentation, indicating a protective role of the protamines against sperm DNA damage. In light of recent studies highlighting the negative effect of sperm DNA damage on ART outcomes, these findings indicate a possible clinical significance for human sperm protamine levels. PMID:16291969

Aoki, Vincent W; Moskovtsev, Sergey I; Willis, Jennifer; Liu, Lihua; Mullen, J Brendan M; Carrell, Douglas T

2005-01-01

348

Cell population indexes of spermatogenic yield and testicular sperm reserves in adult jaguars ( Panthera onca)  

Microsoft Academic Search

The intrinsic yield of spermatogenesis and supporting capacity of Sertoli cells are the desirable indicators of sperm production in a species. The objective of the present study was to quantify intrinsic yield and the Sertoli cell index in the spermatogenic process and estimate testicular sperm reserves by histological assessment of fragments obtained by testicular biopsy of five adult jaguars in

Maria Helena Ferreira de Azevedo; Tarcízio Antônio Rego de Paula; Sérgio Luis Pinto da Matta; Cláudio César Fonseca; Eduardo Paulino da Costa; Deiler Sampaio Costa; Juliano Vogas Peixoto

2010-01-01

349

DECREASING EPIDIDYMAL SPERM RESERVES ENHANCES THE DETECTION OF ETHOXYETHANOL-INDUCED SPERMATOTOXICITY  

EPA Science Inventory

Current test strategies for assessing male reproductive toxicity may be inadequate for estimating risk in humans. High levels of sperm production and existence of large epididymal sperm reserves in most test species may impede the detection of spermatoxicity at low doses. The cur...

350

The use of optical tweezers to study sperm competition and motility in primates.  

PubMed

Optical trapping is a non-invasive biophysical tool which has been widely applied to study physiological and biomechanical properties of cells. Using laser 'tweezers' in combination with custom-designed computer tracking algorithms, the swimming speeds and the relative swimming forces of individual sperm can be measured in real time. This combination of physical and engineering tools has been used to examine the evolutionary effect of sperm competition in primates. The results demonstrate a correlation between mating type and sperm motility: sperm from polygamous (multi-partner) primate species swim faster and with greater force than sperm from polygynous (single partner) primate species. In addition, sperm swimming force linearly increases with swimming speed for each species, yet the regression relating the two parameters is species specific. These results demonstrate the feasibility of using these tools to study rapidly moving (microm s(-1)) biological cells. PMID:17650470

Nascimento, Jaclyn M; Shi, Linda Z; Meyers, Stuart; Gagneux, Pascal; Loskutoff, Naida M; Botvinick, Elliot L; Berns, Michael W

2008-03-01

351

?1 Integrin is an Adhesion Protein for Sperm Binding to Eggs  

PubMed Central

We investigated the role of ?1 integrin in mammalian fertilization and the mode of inhibition of fertilin?-derived polymers. We determined that polymers displaying the Glu-Cys-Asp peptide from the fertilin? disintegrin domain mediate inhibition of mammalian fertilization through a ?1 integrin receptor on the egg surface. Inhibition of fertilization is a consequence of competition with sperm binding to the cell surface, not activation of an egg-signaling pathway. The presence of the ?1 integrin on the egg surface increases the rate of sperm attachment, but does not alter the total number of sperm that can attach or fuse to the egg. We conclude that the presence of ?1 integrin enhances the initial adhesion of sperm to the egg plasma membrane and that subsequent attachment and fusion are mediated by additional egg and sperm proteins present in the ?1 integrin complex. Therefore, the mechanisms by which sperm fertilize wild-type and ?1 knockout eggs are different.

Baessler, Keith A.; Lee, Younjoo; Sampson, Nicole S.

2009-01-01

352

Calaxin drives sperm chemotaxis by Ca2+-mediated direct modulation of a dynein motor  

PubMed Central

Sperm chemotaxis occurs widely in animals and plants and plays an important role in the success of fertilization. Several studies have recently demonstrated that Ca2+ influx through specific Ca2+ channels is a prerequisite for sperm chemotactic movement. However, the regulator that modulates flagellar movement in response to Ca2+ is unknown. Here we show that a neuronal calcium sensor, calaxin, directly acts on outer-arm dynein and regulates specific flagellar movement during sperm chemotaxis. Calaxin inhibition resulted in significant loss of sperm chemotactic movement, despite normal increases in intracellular calcium concentration. Using a demembranated sperm model, we demonstrate that calaxin is essential for generation and propagation of Ca2+-induced asymmetric flagellar bending. An in vitro motility assay revealed that calaxin directly suppressed the velocity of microtubule sliding by outer-arm dynein at high Ca2+ concentrations. This study describes the missing link between chemoattractant-mediated Ca2+ signaling and motor-driven microtubule sliding during sperm chemotaxis.

Mizuno, Katsutoshi; Shiba, Kogiku; Okai, Masahiko; Takahashi, Yusuke; Shitaka, Yuji; Oiwa, Kazuhiro; Tanokura, Masaru; Inaba, Kazuo

2012-01-01

353

Deletion of murine choline dehydrogenase results in diminished sperm motility  

PubMed Central

Choline dehydrogenase (CHDH) catalyzes the conversion of choline to betaine, an important methyl donor and organic osmolyte. We have previously identified single nucleotide polymorphisms (SNPs) in the human CHDH gene that, when present, seem to alter the activity of the CHDH enzyme. These SNPs occur frequently in humans. We created a Chdh?/? mouse to determine the functional effects of mutations that result in decreased CHDH activity. Chdh deletion did not affect fetal viability or alter growth or survival of these mice. Only one of eleven Chdh?/? males was able to reproduce. Loss of CHDH activity resulted in decreased testicular betaine and increased choline and PCho concentrations. Chdh+/+ and Chdh?/? mice produced comparable amounts of sperm; the impaired fertility was due to diminished sperm motility in the Chdh?/? males. Transmission electron microscopy revealed abnormal mitochondrial morphology in Chdh?/? sperm. ATP content, total mitochondrial dehydrogenase activity and inner mitochondrial membrane polarization were all significantly reduced in sperm from Chdh?/? animals. Mitochondrial changes were also detected in liver, kidney, heart, and testis tissues. We suggest that men who have SNPs in CHDH that decrease the activity of the CHDH enzyme could have decreased sperm motility and fertility.—Johnson, A. R., Craciunescu, C. N., Guo, Z., Teng, Y.-W., Thresher, R. J., Blusztajn, J. K., Zeisel, S. H. Deletion of murine choline dehydrogenase results in diminished sperm motility.

Johnson, Amy R.; Craciunescu, Corneliu N.; Guo, Zhong; Teng, Ya-Wen; Thresher, Randy J.; Blusztajn, Jan K.; Zeisel, Steven H.

2010-01-01

354

Sperm penetration assay as an indicator of bull fertility.  

PubMed

To predict the fertility of frozen-thawed bull spermatozoa, a sperm penetration assay (SPA) using zona-free hamster oocytes was optimized, and the assay results were compared with data from field fertility expressed as the non-return rate (NRR). To increase sperm penetration, the spermatozoa were pre-incubated and coincubated with oocytes in media containing various concentrations of heparin (0 to 50 ?g/ml). Coincubation with 10 ?g/ml heparin showed the highest sperm penetration (P<0.05); it is considered to be the optimized SPA method. Sperm fertility index values obtained from WSPA were significantly correlated with the historic average NRR of 46 bulls (P<0.01). To determine the normal range for SPA, we established the lower limits of the sperm fertility index and set the cut-off value at 2.55, at which point the NRR was more than 70%, using the receiver operating characteristic curve. The overall accuracy for the 46 bulls was 95.7% (44/46) for both the low and high NRR, with a sensitivity of 95.5% (21/22) and a specificity of 95.8%. This protocol would make it easier to discriminate bulls according to their sperm fertilizing ability. PMID:22522227

Park, Yoo-Jin; Mohamed, El-Sayed A; Oh, Shin-Ae; Yoon, Sung-Jae; Kwon, Woo-Sung; Kim, Heung-Ruil; Lee, Myeung-Sik; Lee, Kichoon; Pang, Myung-Geol

2012-01-01

355

Human sperm anatomy and endocrinology in varicocele: role of androgen receptor.  

PubMed

The study of androgens involved in male reproduction has been object of intense efforts, while their reported action on human male gametes is limited. We previously described the presence of androgen receptor (AR) in sperm with a role related to the modulation of the PI3K pathway. In the present study, we investigated the expression of AR and its ultrastructural location in normal sperm as well as in spermatozoa obtained from varicocele patients. We observed a reduced AR content in varicocele sperm with respect to healthy sperm by western blot analysis and transmission electron microscopy (TEM). The ultrastructural location of AR was detected mainly on the head membrane as well as in the nucleus, neck, and mitochondria. Influence of dihydrotestosterone (DHT) treatment on cholesterol efflux was increased in normal sperm, while it was reduced or absent in varicocele sperm. To better understand DHT/AR significance in human male gametes, we evaluated triglyceride content and lipase, acyl-CoA dehydrogenase, and glucose-6-phosphate dehydrogenase activities upon DHT treatment. The metabolic outcome glimpsed in normal sperm was an increased metabolic rate, while 'varicocele' sperm economized energy. Taken together, our results reveal DHT and AR as new players in sperm endocrinology, indicating that varicocele sperm may have difficulty in switching to the capacitated status. A decreased AR expression and a consequent reduced responsiveness to DHT in sperm may represent molecular mechanisms involved in the pathophysiology of varicocele leading to male infertility. This study revealed new detrimental effects of varicocele on sperm at the molecular level. PMID:24429393

Guido, Carmela; Santoro, Marta; De Amicis, Francesca; Perrotta, Ida; Panza, Salvatore; Rago, Vittoria; Cesario, Maria Grazia; Lanzino, Marilena; Aquila, Saveria

2014-01-01

356

Sperm competition affects sex allocation but not sperm morphology in a flatworm  

Microsoft Academic Search

Sperm competition has been shown to be an important evolutionary agent affecting the behaviour, physiology, and morphology\\u000a of both males and females. One morphological trait that is particularly likely to be affected by sperm competition is sperm\\u000a size because it is thought to influence the competitiveness of sperm by determining sperm longevity, motility, and\\/or their\\u000a ability to displace competing sperm.

Tim Janicke; Lukas Schärer

2010-01-01

357

Sperm competition and the evolution of male reproductive anatomy in rodents.  

PubMed

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

2005-05-01

358

Increasing the productivity of the nation's urban transportation infrastructure: Measures to increase transit use and carpooling. Final report  

Microsoft Academic Search

The report surveys the growing use of bus and carpool priority measures to increase the productivity of the nation's transportation infrastructure. While it identifies a wide variety of priority measures, the report principally focuses on the planning and operation of exclusive and shared busways and high occupancy vehicle (HOV) facilities. It presents a variety of case studies describing the implementation

J. F. Kain; R. Gittell; A. Daniere; S. Daniel; T. Somerville

1992-01-01

359

Relative testis size and sperm morphometry across mammals: no evidence for an association between sperm competition and sperm length.  

PubMed Central

Understanding why there is extensive variation in sperm form and function across taxa has been a challenge because sperm are specialized cells operating at a microscopic level in a complex environment. This comparative study collates published data to determine whether the evolution of sperm morphometry (sperm total length and separate component dimensions) is associated with sperm competition (when different males' sperm mix and compete for a female's ova) across 83 mammalian species. We use relative testes mass as an indicator of the intensity of sperm competition across taxa: relative investment into testes is widely accepted to predict the level of sperm competition that a species or population endures. Although we found evidence for positive associations between relative testes mass (controlling for allometry) and sperm morphometry across 83 mammalian species, these relationships were phylogenetically dependent. When we appropriately controlled for phylogenetic association using multiple regression within a phylogenetic framework, there was no relationship between relative testes mass and sperm length across mammals. Furthermore, we found no evidence for associations between relative testes mass and sperm head, mid-piece or flagellar lengths, nor was there a relationship with mid-piece or mitochondrial volumes. Results, therefore, indicate that sperm competition does not select for longer or shorter sperm across mammals, and alternative forces selecting on sperm form and function are discussed.

Gage, Matthew J G; Freckleton, Robert P

2003-01-01

360

Acoustic Behavior of Sperm Whales.  

National Technical Information Service (NTIS)

The author's study of sperm whale acoustic behavior shows that sound plays an important role in their lives. Their click sounds apparently are used to maintain contact with other whales underwater and perhaps to communicate individual identity. By trackin...

W. A. Watkins

1977-01-01

361

Effect of estrogens on boar sperm capacitation in vitro  

PubMed Central

Background Mammalian sperm must undergo a series of controlled molecular processes in the female reproductive tract called capacitation before they are capable of penetrating and fertilizing the egg. Capacitation, as a complex biological process, is influenced by many molecular factors, among which steroidal hormone estrogens play their role. Estrogens, present in a high concentration in the female reproductive tract are generally considered as primarily female hormones. However, there is increasing evidence of their important impact on male reproductive parameters. The purpose of this study is to investigate the effect of three natural estrogens such as estrone (E1), 17beta-estradiol (E2) and estriol (E3) as well as the synthetical one, 17alpha-ethynylestradiol (EE2) on boar sperm capacitation in vitro. Methods Boar sperm were capacitated in vitro in presence of estrogens. Capacitation progress in control and experimental samples was analyzed by flow cytometry with the anti-acrosin monoclonal antibody (ACR.2) at selected times of incubation. Sperm samples were analyzed at 120 min of capacitation by CTC (chlortetracycline) assay, immunocytochemistry and flow cytometry with anti-acrosin ACR.2 antibody. Furthermore, sperm samples and capacitating media were analyzed by immunocytochemistry, ELISA with the ACR.2 antibody, and the acrosin activity assay after induced acrosomal reaction (AR). Results Estrogens stimulate sperm capacitation of boar sperm collected from different individuals. The stimulatory effect depends on capacitation time and is highly influenced by differences in the response to estrogens such as E2 by individual animals. Individual estrogens have relatively same effect on capacitation progress. In the boar samples with high estrogen responsiveness, estrogens stimulate the capacitation progress in a concentration-dependent manner. Furthermore, estrogens significantly increase the number of acrosome-reacted sperm after zona pellucida- induced acrosomal reaction. Conclusions We demonstrate here the stimulatory effect of four different estrogens on boar sperm capacitation in vitro. According to our results, there is significant difference in the response to tested estrogens at different capacitation time and among individual animals. In animals with a high response to estrogens, there is a concentration-dependent stimulation of capacitation and individual estrogens have relatively the same effect. Effects of individual estrogens, differences in the response to them by individual animals, their time and concentration-dependent outcomes further contribute to our knowledge about steroidal action in sperm.

2010-01-01

362

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

363

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

364

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

PubMed

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

2014-01-22

365

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.

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

2013-01-01

366

Determination of motility forces of bovine sperm cells using an "optical funnel".  

PubMed

An optical funnel, a new technique for the evaluation of the force of a microorganism, was applied to the determination of the motility force of bovine sperm cells. In this approach, sperm cells, suspended in an aqueous solution, are introduced into a flow cell, to which radiation pressure is applied from the direction opposite to a medium flow. The sperm cell, which is moving in a stream, is captured by radiation pressure and forced to move to the position at which the force induced by the laser radiation is equal to the force induced by a medium flow. The sperm cell then escapes by its own power on the way to this equilibrium (entrapping) position. The radiation force increases with decreasing distance from the focal point, and as a result, the force of the sperm cell can be determined by measuring the position where the sperm cell escaped against the laser irradiation field. The motility force of the sperm cell was measured in aqueous solution at different pH values and potassium ion concentrations. It was possible to measure more than 250 sperm cells in 3 h. Thus, the optical funnel has potential for use as a rapid and repetitive means for the determination of the motility force of the sperm cell. PMID:10857614

Kaneta, T; Mishima, N; Imasaka, T

2000-06-01

367

Sperm bundles in the seminal vesicles of sexually mature Lasius ant males.  

PubMed

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

368

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.

Schumacher, Julia; Rosenkranz, David; Herlyn, Holger

2014-01-01

369

Chromosome studies in 1792 males prior to intra-cytoplasmic sperm injection: the Dutch experience  

Microsoft Academic Search

The chance of a male with severe oligozoospermia or azoospermia achieving a pregnancy has undergone a revolutionary increase with the introduction of the intracytoplasmic sperm injection technique (ICSI). However, since ICSI circumvents part of the natural sperm selection mechanisms, the possible transmission of genetic defects to the offspring is a major concern. Cytogenetic analysis is a relatively simple technique to

J. H. A. M. Tuerlings; HF de France; A. Hamers; R. Hordijk; JO Van Hemel; K Hansson; JMN Hoovers; K Madan; M Van Der Blij-Philipsen; KBJ Gerssen-Schoorl; JAM Kremer; DFCM Smeets; JHAM Tuerlings

1998-01-01

370

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

371

Smoking cigarettes is associated with increased sperm disomy in teenage men 1 1 This manuscript has been reviewed in accordance with the policy of the National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, and approved for publication. Approval does not signify that the contents necessarily reflect the views and policies of the Agency, nor does mention of trade names or commercial products constitute endorsement or recommendation for their use. 8 8 This study was performed in part under the auspices of the U.S. DOE by the Lawrence Livermore National Laboratory under contract W-7405ENG48 with support from U.S. Environmental Protection Agency IA DW8 9936308 and Tobacco-Related Disease Research Program 3RT0223. Recruitment, field work, and conventional semen analyses were supported by the Czech Ministry of the Environment (Teplice Program), the U.S. Environmental Protection Agency\\/U.S. AID and CEC (PHARE II, EC\\/HEA\\/18\\/CZ), and U.S. Environm  

Microsoft Academic Search

Objective: To determine whether moderate cigarette smoking and alcohol consumption in teenage men is associated with increases in disomic sperm and detectable changes in semen quality.Design: Cohort study.Setting: Military recruiting station, Teplice, Czech Republic.Patient(s): Ten current smokers (20 cigarettes per day for at least 2 years, exposure confirmed by urine cotinine) who also consumed alcohol and 15 nonsmokers. All patients

Ji??? Rubes; Xiu Lowe; Dan Moore; Sally Perreault; Valerie Slott; Donald Evenson; Sherry G Selevan; Andrew J Wyrobek

1998-01-01

372

Improving sperm quality and spermatogenesis through a bioactive marine compound: an experimental study.  

PubMed

Dietary lipids may affect sperm membrane structure, fluidity and its susceptibility to oxidative phenomena which may lead to altered sperm viability and proper binding to eggs. Given the recently demonstrated beneficial effects of fish oil diets on turkey fertility and embryo viability, the aim of this study was to test a caviar-derived marine product on spermatogenesis and sperm quality. Sixty mice were divided into four different groups and fed for 3 weeks with normal chow (group A), added with LD-1227 at the dosage of either 5 mg/day (B1) or 10 mg/day (B2) while Group C received standard