Analysis of operating room activities in the dermatology department at Hospital Universitario de Fuenlabrada (2005-2010)

OBJECTIVE

To analyze data corresponding to patients who underwent dermatological surgery in an operating room.

MATERIAL AND METHODS

This was a descriptive, retrospective study of operating room activities in the dermatology department of Hospital Universitario de Fuenlabrada in Madrid between January 2005 and December 2010. We analyzed the relative frequency of a range of patient and procedure-related variables, as well as substitution and cancellation rates, the proportional risk of complications, and operating room efficiency.

RESULTS

In the period analyzed, 11,516 patients underwent surgery: 9351 required minor surgery, 1998 major ambulatory surgery, and 167 surgery requiring hospitalization. Simple excision was the most common procedure (64.7%), and in the majority of cases (85%), the condition was benign. The mean number of patients treated per day was 9.7, and mean operating room efficiency was 71.9%.

CONCLUSIONS

Accurate record-keeping is essential for analyzing operating room activities and comparing results with those from other centers. The analysis of patterns over time shows the effect of changes made on different indicators. In our case, a decrease in operating room efficiency was seen with an increase in the number of patients per day undergoing surgery.

Soil seed bank recovery occurs more rapidly than expected in semi-arid Mediterranean gypsum vegetation

BACKGROUND AND AIMS

Seed banks are critical in arid ecosystems and ensure the persistence of species. Despite the importance of seed banks, knowledge about their formation and the extent to which a seed bank can recover after severe perturbation remains scarce. If undisturbed, soil seed banks reflect a long vegetation history; therefore, we would expect that new soil seed banks and those of undisturbed soils require long periods to become similar with respect to both density and composition. In contrast, if soil seed banks are only a short- to mid-term reservoir in which long-term accumulation constitutes only a tiny fraction, they will recover rapidly from the vegetation. To shed light on this question, we evaluated seed bank formation in a semi-arid gypsum community.

METHODS

Soils from 300 plots were replaced with sterilized soil in an undisturbed semi-arid Mediterranean community. Seasonal changes in seed bank density and composition were monitored for 3 years by comparing paired sterilized and control soil samples at each plot.

KEY RESULTS

Differences in seed bank density between sterilized and control soil disappeared after 18 months. The composition of sterilized seed banks was correlated with that of the control plots from the first sampling date, and both were highly correlated with vegetation. Nearly 24 % of the seed bank density could be attributed to secondary dispersal. Most seeds died before emergence (66·41-71·33 %), whereas the rest either emerged (14·08-15·48 %) or persisted in the soil (14·59-18·11 %).

CONCLUSIONS

Seed banks can recover very rapidly even under the limiting and stressful conditions of semi-arid environments. This recovery is based mainly on the seed rain at small scales together with secondary dispersal from intact seed banks in the vicinity. These results emphasize the relevance of processes occurring on short spatial scales in determining community structure.

Pre-pubertal Di(2-ethylhexyl) Phthalate (DEHP) Exposure of Young Boars Did Not Affect SpermIn vitroPenetration Capacity of Homologous Oocytes Post-puberty

Di(2-ethylhexyl) phthalate (DEHP), a plastic softener used in polyvinylchloride (PVC) products (e.g., plastic bags and medical equipment), has been reported to have toxic effects on animal reproduction and is considered an environmental hazard based, mostly, on rodent studies. However, the doses used in these studies are often considerably higher than that presumed in human exposure. In the present study we used young boars as model animals to assess the effects of pre-pubertal DEHP exposure on the ability of spermatozoa to penetrate homologous oocytes in vitro. Eight pairs of cross-bred male boar siblings were used. One brother in each pair became, at random, the test animal exposed to DEHP per os, three times a week, from 3 to 7 weeks of age while the other acted as the control, i.e., placebo-exposed. Semen was collected and frozen between 8 and 9 months of age and stored until spermatozoa were evaluated for their ability to in vitro penetrate in vitro-matured homologous oocytes post-thaw. Both the penetration rate and the number of spermatozoa per oocyte were considered within expected ranges for frozen boar semen of good quality. Penetration rate did not significantly differ (p > 0.05) between the groups with DEHP-exposed: 50%; control: 59%, which could be owing to a large variation between boars, and between replicates. The number of spermatozoa in the ooplasm was low and similar (p > 0.05) between the groups with DEHP-exposed: 1.5 and the control: 1.7. Under the conditions of the present experiment, pre-pubertal exposure to DEHP does not seem to cause a deleterious effect on the in vitro fertilizing ability of frozen spermatozoa post-puberty.

Improving the efficiency of insemination with sex-sorted spermatozoa

The sorting of X- and Y-chromosome-bearing spermatozoa by flow cytometry is nowadays one of the most apt assisted-reproduction technologies in livestock production. Potential economic and biological benefits, as well as those related to easier management of herds, have been reported arising out of the application of this technique, especially in cattle. Yet, the sex-sorting procedure induces damage to spermatozoa, affecting their function and fertilizing ability. Different species present varying degrees of susceptibility to damage from the sorting process and each has its own requirements for sex-sorted insemination procedures. Thus, several new protocols and strategies have been designed for the handling of sorted spermatozoa, with the main objective of optimizing their fertilizing ability and the consequent application of flow-cytometric sex-sorting technology. This article reviews current advances in this technology, pointing out the components to be improved before this technology may be widely applied in different domestic species.

Optimal characteristics of spermatozoa for semen technologies in pigs

Despite the great potential of sperm technologies such as sperm cryopreservation and sperm sex sorting for the improvement of different aspects of swine production, artificial insemination with fresh or stored semen is currently the only sperm technology used at a commercial scale in the pig industry. The lower reproductive performance associated with the use of these sperm technologies is the reason for such limited use. Since optimal characteristics are required for successful application of frozen-thawed and sex-sorted boar spermatozoa, the present paper summarises the value of the current available methods for their functional assessment as well as the effects of these technologies on boar sperm functionality. In addition, strategies developed to reduce sperm damage and improve the yields of both sperm technologies in swine production are also reviewed with particular attention to the contributions of the authors.

In vitro maturation of porcine oocytes with retinoids improves embryonic development

In the present study, the effects of retinoid metabolite administration during in vitro maturation (IVM) on oocyte maturation, parameters of in vitro fertilisation (IVF) and embryo development were examined. Varying concentrations of 9-cis retinoic acid (RA; 0, 5, 50 and 500 nm; Experiment 1) and all-trans retinol (ROH; 0, 125, 1250 and 12 500 nm; Experiment 2) were included in the maturation medium. Cumulus-oocyte complexes were matured in vitro and inseminated with frozen-thawed spermatozoa. Presumptive zygotes were cultured for 16 h to assess IVF parameters or for 7 days to assess embryo development and quality. In Experiment 1, the oocyte maturation rate to metaphase II was significantly decreased (P < 0.001), with values below 5%, in the presence of the highest concentration of RA (500 nm). However, 5 and 50 nm RA had no effect compared with control. Treatment with 5 nm RA improved the blastocyst development rate (P < 0.001). In Experiment 2, the oocyte maturation rate did not differ between 125 and 1250 nm ROH treatment groups and control. However, treatment with 12 500 nm ROH was deleterious because no matured oocytes were observed following the treatment. The penetration rate was lower in the group treated with 1250 nm ROH compared with the 125 nm ROH-treated and control groups, but the blastocyst formation rate did not differ among the three groups. In conclusion, 5 nm RA in the IVM medium significantly increased the blastocyst formation rate, suggesting that RA may play an important role during IVM.

PSP-I/PSP-II spermadhesin exert a decapacitation effect on highly extended boar spermatozoa

PSP-I/PSP-II heterodimer is a major protein of boar seminal plasma that is able to preserve, in vitro, the viability, motility and mitochondrial activity of highly-extended boar spermatozoa. However, a relationship between the protective effects of the heterodimer and sperm capacitation is still unclear. The present study investigated the effect of the PSP-I/PSP-II (1.5 mg/mL) on membrane stability, intracellular calcium concentration ([Ca(2+)](I)) and plasma membrane and acrosome integrity of highly extended boar spermatozoa. Boar spermatozoa were diluted to 1 x 10(6) spermatozoa/mL and incubated at 38 degrees C in Phosphate-buffered saline (PBS) for 10, 30, 60, 120 and 300 min or in modified Tris-buffered medium (mTBM) for 10, 20, 30, 60 and 120 min. After each incubation time, the membrane stability (using Merocyanine-540/Yo-Pro-1), elevation of [Ca(2+)](I) (using Fluo-3-AM/PI) and the sperm plasma membrane and acrosome integrity (using SYBR-14/PI/PE-PNA) were evaluated by flow cytometry. As expected, exposure of the spermatozoa to the PSP-I/PSP-II preserved the plasma membrane and acrosome integrity compared to non-exposed spermatozoa in both media PBS and mTBM (p < .01). The evaluation of membrane stability showed no differences in the percentages of viable sperm with instable plasma membrane in the presence of the PSP-I/PSP-II compared to controls irrespective of the dilution media. The evaluation of the [Ca(2+)](I) levels showed that while spermatozoa incubated in mTBM and exposed to PSP-I/PSP-II had lower [Ca(2+)](I) than controls (39.08% vs. 47.97%, respectively; p < .05), no differences were observed in those samples incubated in PBS. However, a temporal evaluation of the samples showed that a similar proportion of live spermatozoa were able to achieve high levels of [Ca(2+)](I) and membrane instability independent of the presence of PSP-I/PSP-II. In conclusion, PSP-I/PSP-II exert a non-permanent decapacitation effect on highly extended boar spermatozoa that is related with a delay in the increase of [Ca(2+)](I) levels.

Immunohistochemical increase in cyclooxygenase-2 without apoptosis in different brain areas of subchronic nicotine- and D-amphetamine-treated rats

Cyclooxygenase-2 (COX-2) upregulation has been related to both neurodegeneration and physiological processes. To clarify whether nicotine-induced upregulation of COX-2 occurs, and to analyse its significance, a comparative immunohistochemical and Western blot study was performed on the frontoparietal cortex, hippocampus and cerebellar cortex of rats treated (14 days) with nicotine, D(+)amphetamine (0.35 and 1.16 mg free base/kg/day, respectively), or both drugs simultaneously. None of these treatments promoted neuronal apoptosis. Lipid peroxidation increased in the hippocampus of the nicotine-treated rats and in all the brain regions examined in the D(+)amphetamine rats, but not in the double-treated animals. Both molecules increased the COX-2 content (as determined by the number of immunopositive neurons and the intensity of their immunodeposits) in an area-, layer- and neuron type-dependent manner, in all brain regions in which a large number of COX-2 immunopositive neurons were observed in controls (the somatosensory cortical areas, CA-1, CA-3, the gyrus dentatus, the ectorhinal/perirhinal areas, and the gyrus cingularis). No increase was seen in the motor cortical areas, while a reduction was recorded in the cerebellar cortex; these regions had only a few immunopositive neurons in controls. Western blot analysis revealed a 50-80% increase in COX-2 in the brain cortex and hippocampus of nicotine-treated rats, and similar increases (150-200%) in the cortex of the D(+)amphetamine- and nicotine + D(+)amphetamine-treated rats. Nicotine-induced upregulation of COX-2 seems to be related to neuronal plasticity rather than neurodegeneration. Nicotine agonists might be useful in the treatment of cognitive disorders.

70 EFFECT OF CRYOPROTECTANT CONCENTRATION ON THE IN VITRO SURVIVAL AND CELL PROLIFERATION OF PORCINE BLASTOCYSTS VITRIFIED USING THE OPEN PULLED STRAW SYSTEM

The objective of the present project was to study the effect of the concentrations of ethylene glycol (EG) and dimethyl sulfoxide (DMSO) during vitrification on the survival and hatching rates of porcine blastocysts. Embryos were collected by laparotomy from weaned crossbred sows (n = 18), vitrified, and warmed (one-step dilution) as described by Cuello et al. (2004 Theriogenology 62, 1144–1152). Vitrification was performed in different concentrations of EG and DMSO (15%, 16%, and 17% v/v for each cryoprotectant) or in an EG-based medium (40% v/v) using superfine open pulled straws. Fresh and vitrified blastocysts were cultured for 24 h in TCM199 and assessed by stereomicroscopy during the culture. Blastocysts that reformed their blastocoelic cavities after warming, displaying a normal zona pellucida and excellent appearance, were considered viable. The in vitro survival rate was defined as the ratio of viable embryos divided by the total number of embryos cultured. The hatching rate is determined as the ratio of the number of embryos hatched in vitro to the total number embryos cultured. Some vitrified and fresh embryos classified as viable were processed for Hoechst 33342 staining and proliferation cell nuclear antigen (PCNA) inmunolocalization. The proliferation index was defined as the number of PCNA-positive nuclei divided by the total number of nuclei stained with Hoechst 33342. Data were analyzed by ANOVA using the MIXED procedure (SPSS version 11.5; SPSS, Inc., Chicago, IL, USA). Data were expressed as mean values � SEM. The survival rate was similar for fresh and vitrified blastocysts, except for blastocysts vitrified using 15% cryoprotectants, which displayed a lower (P < 0.05) survival rate (84.2 � 4.8%) than fresh blastocysts (94.6 � 5%) and blastocysts vitrified using 40% EG, 16%, or 17% EG-DMSO (88.8 � 4.9, 96.8 � 4.9, and 96.4 � 5%, respectively). Fresh blastocysts showed a higher (P < 0.05) hatching rate (80.7 � 4.5%) than their vitrified counterparts (range: 48.4 � 7.7–55.3 � 7.8%). Vitrified and fresh blastocysts showed similar cell proliferation indexes (range: 75.8 � 3.2–83.7 � 3). When only hatched blastocysts among groups were compared, the proliferation rate decreased (P < 0.05) after vitrification with 17% EG-DMSO. Among vitrification groups, there was no significant difference in the number of total cells. However, vitrified blastocysts had a lower (P < 0.05) total cell number (range: 116.6 � 6.7–124.8 � 6.6) than fresh blastocysts (195.5 � 11.4). In conclusion, under our experimental conditions, the concentration of EG-DMSO can be decreased until 16% in the vitrification medium with no reduction of the in vitro developmental ability of the blastocysts. In addition, a 40% EG-based medium can be used for vitrification with results similar to those achieved using a medium containing 16% EG-DMSO.

Factors affecting the success rate of porcine embryo vitrification by the Open Pulled Straw method

The objectives of this study were: (1) to evaluate the influence of porcine embryo developmental stage on in vitro embryo development after vitrification, (2) to study the efficiency of the one-step dilution procedure, compared with conventional warming, for vitrified embryos at different stages of development, and (3) to determine the influence of the embryo donor on the in vitro survival of vitrified embryos at morulae and blastocyst stages. Two to four cell embryos, morulae and blastocysts were collected by laparotomy from weaned crossbred sows (n=55). Vitrification and conventional warming were performed using the OPS procedure with Superfine Open Pulled Straws (SOPS). For one-step dilution, embryos were placed in 800 microl TCM199-HEPES containing 20% of new born calf serum and 0.13 M sucrose for 5 min. To evaluate development, two to four cell embryos, morulae and blastocysts were cultured in vitro for 120, 48 and 24h, respectively. Some fresh embryos from each developmental stage were not vitrified and cultured as controls. Embryos were morphologically evaluated for their developmental capacity during the in vitro culture by stereomicroscopy. The total cell number of embryos was assessed by Hoechst-33342 staining and fluorescence microscope observation. There was a significant effect of the stage of development on the in vitro survival, perihatching rate and the number of cells of embryos after vitrification and warming (Experiment 1; p<0.001). The survival and perihatching rates of two to four cell embryos were lower than those obtained for morulae and blastocysts (p<0.001). No differences (p>0.05) in survival rates were found between vitrified and fresh blastocysts. The warming procedure did not affect the development and total cell number of vitrified two to four cell embryos, morulae or blastocysts (Experiment 2). However, donor had a significant effect (p<0.001) on the in vitro development and the number of cells of morulae and blastocysts after vitrification and warming (Experiment 3). In conclusion, the embryo developmental stage and the embryo donor were important factors that affected the development of porcine embryos after OPS-vitrification and warming. OPS-vitrification and the one-step dilution are efficient procedures to be used with intact porcine morulae and blastocysts.

Improving the fertilizing ability of sex sorted boar spermatozoa

The sex sorting of spermatozoa by flow cytometry induces damage, since sperm cells are highly diluted, affecting their functionality and fertilizing ability. In this work it was investigated whether the concentration of sex sorted spermatozoa by the sedimentation method, rather than centrifugation, in combination with the presence of the seminal plasma protein PSP-I/PSP-II heterodimer may improve their fertilizing ability. Spermatozoa were sorted by flow cytometry and collected in BTS with 10% of seminal plasma (group C: control) or with 1.5mg/mL of PSP-I/PSP-II heterodimer (group H). Collected spermatozoa from each medium were split into two aliquots. One aliquot of each group was centrifuged (800 x g/5 min) just after sorting and stored 16-18 h at 17 degrees C (groups Cc and Hc) at 6 x 10(6)sperm/mL. The second aliquot was directly stored at 17 degrees C for 16-18 degrees C (group Cs and Hs). After storage the supernatant was discarded and the sedimented pellet adjusted to 6 x 10(6)sperm/mL. Membrane integrity, acrosome status and motility characteristics of spermatozoa from all groups were assessed. Post-weaning pre-ovulatory sows were inseminated by laparoscopy into the oviduct with 0.3 x 10(6) sex sorted spermatozoa to assess their ability to penetrate oocytes in vivo. Putative zygotes were collected 18 h after insemination by washing the oviduct. Penetration and monospermic rates were evaluated. After 16-18 h of storage, centrifuged spermatozoa collected with 10% seminal plasma or 1.5 mg/mL PSP-I/PSP-II heterodimer after sex sorting showed lower (p<0.05) percentages of membrane integrity, motility and fertilization than sedimented spermatozoa. Overall, the presence of 10% seminal plasma or PSP-I/PSP-II heterodimer did not affect the results. However, a positive effect of PSP-I/PSP-II heterodimer (p<0.05) was observed in sedimented spermatozoa. Hence, our results indicate that the sedimentation method in the presence of PSP-I/PSP-II heterodimer improves the in vivo fertilizing ability of sex sorted boar spermatozoa.

Vitrification of in vitro cultured porcine two-to-four cell embryos

The objective of this experiment was to evaluate the effect of a 5-day period of in vitro culture of two-to-four cell porcine embryos up to the blastocyst stage on their ability to survive vitrification and warming. In order to increase the cooling rate, superfine open pulled straws and Vit-Master((R)) technology were used for vitrification. Two-to-four cell embryos were collected from weaned sows (n=11) on day 2 (D0=onset of estrus). Some embryos (N=63) were vitrified within 3h after collection, warmed and cultured for 120h (Group V2). Additionally, 81 two-to-four cell embryos were cultured for 96h in order to obtain blastocysts; these were then vitrified, warmed and cultured for 24h (Group VB; N=65). The remaining two-to-four cell embryos were used as controls and thus not vitrified (control embryos; N=70) but were cultured in vitro for 120h. The V2, VB and control embryos were evaluated for their developmental progression and morphology during culture. All embryos (V2, VB and controls) were fixed on the same day of development in order to assess the total number of blastomeres. The survival and blastocyst formation rates obtained from V2 embryos were very poor (9.6+/-0.7% and 3.2+/-0.5%, respectively). The survival and hatching rates of VB embryos (75.0+/-0.69% and 33.6+/-0.13%) were lower (p<0.001) than those obtained with control embryos (89.1+/-0.8% and 47.5+/-0.12%). Hatched VB embryos had a lower (p<0.01) total cell number than hatched control embryos (70.3+/-4.5 versus 90.6+/-3.2, respectively). There was no difference between expanded VB and control blastocysts. In conclusion, blastocysts derived from in vitro culture of two-to-four cell pig embryos could be successfully vitrified using SOPS straws and Vit-Master.

Retained Functional Integrity of Bull Spermatozoa after Double Freezing and Thawing Using PureSperm® Density Gradient Centrifugation

The main aim of this study was to compare the motility and functional integrity of bull spermatozoa after single and double freezing and thawing. The viability and morphological integrity of spermatozoa selected by PureSperm density gradient centrifugation after cryopreservation of bovine semen in two commercial extenders (Experiment 1) and the function of bull spermatozoa before and after a second freezing and thawing assisted by PureSperm selection (Experiment 2) were examined. On average, 35.8 +/- 12.1% of sperm loaded onto the PureSperm density gradient were recovered after centrifugation. In Experiment 1, post-thaw motility and acrosome integrity were higher for spermatozoa frozen in Tris-egg yolk extender than in AndroMed, whether the assessments were made immediately after thawing [80.4 +/- 12.7 vs 47.6 +/- 19.0% motile and 78.8 +/- 8.3 vs 50.1 +/- 19.5% normal apical ridge (NAR), p < 0.05] or after preparation on the gradient (83.3 +/- 8.6 vs 69.4 +/- 15.9% motile and 89.5 +/- 7.2 vs 69.1 +/- 11.4% NAR, p < 0.05). For semen frozen in Tris-egg yolk extender, selection on the PureSperm gradient did not influence total motility but significantly improved the proportion of acrosome-intact spermatozoa. After the gradient, both the total motility and percentage of normal acrosomes increased for spermatozoa frozen in AndroMed (Minitüb Tiefenbach, Germany). In Experiment 2, there was no difference in sperm motility after the first and second freeze-thawing (82.9 +/- 12.7 vs 68.8 +/- 18.7%). However, the proportion of acrosome-intact spermatozoa was significantly improved by selection through the PureSperm gradient, whether measured by phase contrast microscopy (78.9 +/- 9.7 vs 90.4 +/- 4.0% NAR, p < 0.05) or flow cytometry (53.4 +/- 11.7 vs 76.3 +/- 6.0% viable acrosome-intact spermatozoa, p < 0.001). The improvement in the percentage of spermatozoa with normal acrosomes was maintained after resuspension in the cooling extender and cooling to 4 degrees C (88.2 +/- 6.2) and after re-freezing and thawing (83.6 +/- 6.56% NAR). However, flow cytometric assessment of the sperm membranes revealed a decline in the percentage of viable spermatozoa with intact membranes after the second freezing and thawing compared with after gradient centrifugation (76.3 +/- 6.0% vs 46.6 +/- 6.6%, p < 0.001) to levels equivalent to those obtained after the first round of freeze-thawing (53.4 +/- 11.7% viable acrosome-intact spermatozoa). Sperm movement characteristics assessed by computer-assisted analysis were unaffected in the population selected on the PureSperm gradients but declined after cooling of the selected and extended spermatozoa to 4 degrees C. There was no further change in these kinematic measurements after the cooled spermatozoa had undergone the second round of freeze-thawing. These results demonstrate that bull semen can be frozen and thawed, followed by a second freeze-thawing cycle of a population of spermatozoa selected by PureSperm, with retained motility and functional integrity. This points to the possibility of using double frozen spermatozoa in bovine artificial insemination programmes and to the potential benefits of PureSperm density gradient centrifugation for the application of cryopreserved bull spermatozoa to other biotechnological procedures such as flow cytometric sex sorting followed by re-freezing and thawing.

Effect of storage in short- and long-term commercial semen extenders on the motility, plasma membrane and chromatin integrity of boar spermatozoa

For artificial insemination (AI) in pigs, preservation of liquid boar semen at 16-20 degrees C is still common practice as sperm cryopreservation remains suboptimal in this species. To meet the different needs of the swine industry, several extenders have been developed to preserve semen in liquid form for short--and long-term storage. In the present study, three different commercial extenders devised for short-term (BTS+) or long-term preservation (MR-A and X-Cell), were used to test whether storage of semen from four mature, fertile boars at 17 degrees C for 96 h would affect sperm characteristics relevant for fertility, such as motility, membrane integrity and chromatin stability. Computer-assisted sperm analysis, and stainings with the acylated membrane dye SYBR-14/propidium iodide, and acridine orange in connection with flow cytometry were used to evaluate these variables. Percentages of total motile spermatozoa decreased slightly, but significantly, after 72-96 h. While membrane integrity values varied during the period of study, no significant changes in either membrane integrity or chromatin stability were, however, registered. This suggests a customary 96-day storage at 17 degrees C in these extenders was too short an interval to cause losses of integrity in nuclear DNA in the boar population studied.

Immunolocalization and possible functional role of PSP-I/PSP-II heterodimer in highly extended boar spermatozoa

PSP-I/PSP-II heterodimer is a major protein of boar seminal plasma which is able to preserve, in vitro, the viability, motility, and mitochondrial activity of highly extended boar spermatozoa for at least 5 hours. However, little is known about the binding pattern of the heterodimer to the sperm plasma membrane and its eventual relation with the maintenance of the sperm functionality. The present study investigated the effect of exposing highly extended boar spermatozoa (1 million/mL) to 1.5 mg/mL of PSP-I/PSP-II for 0.5, 5, and 10 hours at 38 degrees C on sperm characteristics and the changes in PSP-I/PSP-II localization as a result of both the addition of PSP-I/PSP-II to the extender and the incubation time. Exposure of the spermatozoa to PSP-I/PSP-II preserved sperm viability, motility, and mitochondrial activity when compared to nonexposed spermatozoa. This protective effect lasted for 10 hours (P < .05). After immunolabeling of highly extended semen with rabbit monospecific polyclonal antibody against PSP-I/PSP-II, the percentage of immunopositive spermatozoa declines over time from 71% (0.5 hours) to 49% (10 hours). However, more than 80% of spermatozoa remained labeled during the 10-hour incubation period if PSP-I/PSP-II was added. Scanning electron microscopy revealed 4 different binding patterns. The heterodimer was mainly localized to the acrosomal area, being redistributed to the postacrosomal area or lost during in vitro incubation. In conclusion, the protective effect of the heterodimer appears to be related to its adhesion to the acrosomal area, and the loss of this protective effect coincides with a stepwise redistribution of PSP-I/PSP-II during incubation.

Dissecting the Protective Effect of the Seminal Plasma Spermadhesin PSP-I/PSP-II on Boar Sperm Functionality

To dissect the protective activity of PSP-I/PSP-II, the effect of the isolated subunits PSP-I and PSP-II and their affinity-purified tryptic peptide and glycan fractions on the viability, mitochondrial activity, and motility of highly diluted boar spermatozoa was investigated. High dilution exerted a negative effect on control spermatozoa. Incubation of spermatozoa with PSP-I/PSP-II or with its PSP-II subunit had a protective effect on sperm functionality, high mitochondrial membrane potential, and sperm motility. These effects were less pronounced when spermatozoa were incubated with the PSP-I subunit. It was noteworthy that motility was abolished by incubation of spermatozoa with isolated PSP-I. Trypsin-degraded PSP-I/PSP-II, PSP-I, and PSP-II reproduced the effects of the native proteins. Incubating spermatozoa with the glycan-depleted tryptic-peptide fraction of PSP-I/PSP-II for 5 hours preserved a higher percentage of viable spermatozoa than when sperm was incubated for the same time with the native heterodimer, trypsin-digested PSP-I/PSP-II, the glycan fraction or without added proteins. However, sperm motility decreased as the concentration of added peptide fraction increased. On the other hand, spermatozoa incubated with the glycan fraction showed lower values than spermatozoa incubated with the peptide fraction. We concluded that the subunits of the PSP-I/PSP-II heterodimeric spermadhesin exert different activities on sperm functions. The finding that the beneficial effect of the native PSP-I/PSP-II on the functionality of highly diluted boar spermatozoa is largely preserved in its isolated PSP-II subunit and does not appear to require the glycan moiety points to a peptide moiety as a potential sperm function-preserving additive of highly diluted boar spermatozoa.

349 IMPROVING THE FUNCTIONALITY OF STORED FLOW CYTOMETRICALLY SEX-SORTED BOAR SPERMATOZOA: SEDIMENTATION VS. CENTRIFUGATION

Centrifugation has been the routine procedure used to concentrate the highly diluted spermatozoa obtained after sorting. However, this harmful procedure has a detrimental effect on the lifespan of the spermatozoa, particularly when a short-term storage period is required to perform the inseminations in the farms. The aim of the study was to evaluate the procedure of concentration by sedimentation of the flow cytometrically sex-sorted boar spermatozoa after a 24-h storage period, in terms of sperm functionality and recovery efficiency. Spermatozoa were sex-sorted by flow cytometry (Johnson and Welch 1999 Theriogenology 52, 1323-1342) and collected in 50-mL tubes containing 5 mL of Beltsville thawing solution (BTS) with 10% seminal plasma (SP). The collected samples were split into two aliquots. The first aliquot was concentrated by centrifugation (800g/5 min) just after sorting and stored at 17�C for 24 h at a concentration of 6 � 106 sperm/mL. The second aliquot was directly stored (0.5 � 106 sperm/mL) at 17�C for 24 h. In this case, after storage the supernatant was discarded and the pellet obtained by sedimentation was adjusted to 6 � 106 sperm/mL. For assessment of the sperm functionality after the storage, motility and viability of the spermatozoa were analyzed using a CASA system (Sperm Class Analyzer; Microptic, Barcelona, Spain) and a EPICS XL flow cytometer (Coulter Corporation, Inc., Miami, FL, USA) after the sperm were stained with propidium iodide and SYBR-14, respectively. For assessment of the recovery efficiency, the total number of spermatozoa in each sample was counted. The results are expressed as percentages of five replicates. Statistical analysis was performed using a �2 test. Percentages of motile and viable spermatozoa just after sorting were 80% and 83.3%, respectively. After storage at 17�C for 24 h, the percentage of viable spermatozoa was significantly higher (P < 0.05) in settled spermatozoa (82.4%) compared to centrifuged spermatozoa (63.3%). Similarly, the percentage of motile spermatozoa was significantly higher (P < 0.05) in settled spermatozoa (78.3%) compared to centrifuged spermatozoa (58.3%), as was the percentage of progressive motility (63.6% vs. 35.5%, respectively; P < 0.05). Interestingly, the percentage of cell recovery was significantly higher (P < 0.05) after sedimentation (80% of the sorted population) than after centrifugation (60.3% of the sorted population). The results show that sedimentation is more beneficial than centrifugation when short-term storage of sex-sorted boar sperm is required. This work was supported by CDTI and Fundaci�n Seneca.

Vazquez J. 352 IMPROVING THE EFFICIENCY OF LAPAROSCOPIC INTRAOVIDUCTAL INSEMINATION WITH SEX-SORTED BOAR SPERMATOZOA

The insemination of a low number of sex-sorted spermatozoa is a critical issue that must be solved in order to enable the commercial application of this technology in pigs. A new procedure for laparoscopic intraoviductal insemination in sows has recently been reported (Vazquez et al. 2005 Reprod. Dom. Animals 40, 375 abst.). To improve the efficiency of this technique, this experiment was designed to determine the influence of insemination time, relative to the time of ovulation, on the number and quality of zygotes recovered after laparoscopic insemination of sows with sex-sorted spermatozoa. Spermatozoa were stained with Hoechst 33342 and sexed using the EPICS Altra flow sorter (Coulter Corporation, Miami, FL, USA) modified to operate at 42 psi for spermatozoa. Sorted spermatozoa were collected in tubes containing 1.5 mL of TEST-yolk (2%)-seminal plasma (10%). Post-weaning crossbred sows (n = 212; parity 2-4) were hormonally treated with eCG (Folligon; Intervet, Boxmeer, The Netherlands) and hCG (Veterin Corion, Divasa, Spain) and their ovaries were examined using transrectal ultrasonography at intervals of 4 h from 30 h after hCG injection to the laparoscopic insemination. Sows were allotted into three groups according to their ovarian status at insemination: preovulatory (P; n = 131), ovulating (O; n = 43), and ovulated (CL; n = 38) follicles. Follicle status was reconfirmed at insemination by direct observation using the laparoscope. Sows were inseminated in both oviducts with 0.3 million sex-sorted spermatozoa in 0.1 mL of extender. Eighteen hours later, putative zygotes were collected by washing the oviducts after laparotomy, fixed, stained with lacmoid, and examined by phase-contrast microscopy. Penetration rates were evaluated as numbers of monospermic and polyspermic oocytes per oocytes collected. Monospermic rates were evaluated as numbers of monospermic oocytes per oocytes penetrated. Data were analyzed by ANOVA. The number of putative zygotes collected were 2825, 957, and 736 for P, O, and CL groups, respectively. Penetration rates were not different (P > 0.05) among groups (90.4%, 94.5%, and 93.7% for P, O, and CL, respectively). However, the monospermic rate was significantly higher (P < 0.05) in the P group (97.4%) when compared to the O or CL groups (66.7% and 5.1% for O and CL, respectively). Moreover, percentages of sows with six or more zygotes, potentially able to carry the pregnancy to term, were 90.8% and 46.5% for P and O groups, respectively (P < 0.05). No sow of the CL group presented six or more zygotes. In conclusion, laparoscopic insemination should be performed only in sows with preovulatory follicles when sex sorted spermatozoa are inseminated using this technology. This work was supported by CDTI and Fundacion Seneca.