Artificial insemination of all ejaculated sperm fractions accelerates embryo development and increases the uterine vascularity in the pig.

The semen of boar is characterized by ejaculation in well-differentiated fractions with specific concentration, composition, and volume. The 'sperm-rich fraction' (SRF), the most concentrated seminal fraction, is habitually collected in insemination centers to make artificial insemination (AI) doses. The absence of the other fractions in AI doses could alter the uterine reaction to AI and not trigger essential responses that could maximize fertility. Thus, there is an urge to ascertain the impact of different ejaculate fractions on the uterus after AI to optimize the semen doses. This work analyzed specific parameters related to fertility in pregnant artificially inseminated sows (n = 15) with ac-cumulative fractions of the semen of boars (n = 6): F1, composed of the sperm-rich fraction (SRF); F2, composed of F1 plus the intermediate fraction; F3, composed of F2 plus the post-SRF. Non-inseminated sows (n = 5) were included as control (C). The different types of seminal dose did not affect the number of ovulated follicles (CL; corpora lutea, p > 0.05) but did affect the embryo development (p < 0.05). The proportion of embryos in morula stages was significantly higher in AI-F1 sows (84.4%, p < 0.05). Morulas and blastocysts were balanced in AI-F2 or AI-F3 (p > 0.05). Independently of the type of seminal dose (F1, F2, or F3), we observed by immunohistochemistry that AI significantly increased uterine vascularization, although with some anatomical differences. The cranial region of the uterine horns was significantly more vascularized in AI-F1 or AI-F2 sows (26.7 ± 2.3 and 28.6 ± 2.0%, respectively), and AI-F3 showed significantly less vascularization at that point (17.8 ± 1.6%, p < 0.05). To summarize, the synergistic effect of all ejaculate fractions accelerates embryo development, at least during the preimplantation period, and increases the uterine reaction to AI in certain parts of the uterus.

Sperm functionality is differentially regulated by porcine oviductal extracellular vesicles from the distinct phases of the estrous cycle.

Context Extracellular vesicles (EVs) derived from the oviductal fluid (oEVs) play a critical role in various reproductive processes, including sperm capacitation, fertilisation, and early embryo development. Aims To characterise porcine oEVs (poEVs) from different stages of the estrous cycle (late follicular, LF; early luteal, EL; mid luteal, ML; late luteal, LL) and investigate their impact on sperm functionality. Methods poEVs were isolated, characterised, and labelled to assess their binding to boar spermatozoa. The effects of poEVs on sperm motility, viability, acrosomal status, protein kinase A phosphorylation (pPKAs), tyrosine phosphorylation (Tyr-P), and in in vitro fertility were analysed. Key results poEVs were observed as round or cup-shaped membrane-surrounded vesicles. Statistical analysis showed that poEVs did not significantly differ in size, quantity, or protein concentration among phases of the estrous cycle. However, LF poEVs demonstrated a higher affinity for binding to sperm. Treatment with EL, ML, and LL poEVs resulted in a decrease in sperm progressive motility and total motility. Moreover, pPKA levels were reduced in presence of LF, EL, and ML poEVs, while Tyr-P levels did not differ between groups. LF poEVs also reduced sperm penetration rate and the number of spermatozoa per penetrated oocyte (P Conclusions poEVs from different stages of the estrous cycle play a modulatory role in sperm functionality by interacting with spermatozoa, affecting motility and capacitation, and participating in sperm-oocyte interaction. Implications The differential effects of LF and LL poEVs suggest the potential use of poEVs as additives in IVF systems to regulate sperm-oocyte interaction.

Different seminal ejaculated fractions in artificial insemination condition the protein cargo of oviductal and uterine extracellular vesicles in pig.

The seminal plasma (SP) is the liquid component of semen that facilitates sperm transport through the female genital tract. SP modulates the activity of the ovary, oviductal environment and uterine function during the periovulatory and early pregnancy period. Extracellular vesicles (EVs) secreted in the oviduct (oEVs) and uterus (uEVs) have been shown to influence the expression of endometrial genes that regulate fertilization and early embryo development. In some species, semen is composed of well-separated fractions that vary in concentration of spermatozoa and SP composition and volume. This study aimed to investigate the impact of different accumulative fractions of the porcine ejaculate (F1, composed of the sperm-rich fraction, SRF; F2, composed of F1 plus the intermediate fraction; F3, composed of F2 plus the post-SRF) on oEVs and uEVs protein cargo. Six days after the onset of estrus, we determined the oEVs and uEVs size and protein concentration in pregnant sows by artificial insemination (AI-sows) and in non-inseminated sows as control (C-sows). We also identified the main proteins in oEVs and uEVs, in AI-F1, AI-F2, AI-F3, and C-sows. Our results indicated that although the size of EVs is similar between AI- and C-sows, the protein concentration of both oEVs and uEVs was significantly lower in AI-sows (p < 0.05). Proteomic analysis identified 38 unique proteins in oEVs from AI-sows, mainly involved in protein stabilization, glycolytic and carbohydrate processes. The uEVs from AI-sows showed the presence of 43 unique proteins, including already-known fertility-related proteins (EZR, HSPAA901, PDS). We also demonstrated that the protein composition of oEVs and uEVs differed depending on the seminal fraction(s) inseminated (F1, F2, or F3). In conclusion, we found specific protein cargo in oEVs and uEVs according to the type of semen fraction the sow was inseminated with and whose functions these specific EVs proteins are closely associated with reproductive processes.

Reproductive fluids, used for the in vitro production of pig embryos, result in healthy offspring and avoid aberrant placental expression of PEG3 and LUM.

BACKGROUND: In vitro embryo production (IVP) and embryo transfer (ET) are two very common assisted reproductive technologies (ART) in human and cattle. However, in pig, the combination of either procedures, or even their use separately, is still considered suboptimal due to the low efficiency of IVP plus the difficulty of performing ET in the long and contorted uterus of the sow. In addition, the potential impact of these two ART on the health of the offspring is unknown. We investigated here if the use of a modified IVP system, with natural reproductive fluids (RF) as supplements to the culture media, combined with a minimally invasive surgery to perform ET, affects the output of the own IVP system as well as the reproductive performance of the mother and placental molecular traits. RESULTS: The blastocyst rates obtained by both in vitro systems, conventional (C-IVP) and modified (RF-IVP), were similar. Pregnancy and farrowing rates were also similar. However, when compared to in vivo control (artificial insemination, AI), litter sizes of both IVP groups were lower, while placental efficiency was higher in AI than in RF-IVP. Gene expression studies revealed aberrant expression levels for PEG3 and LUM in placental tissue for C-IVP group when compared to AI, but not for RF-IVP group. CONCLUSIONS: The use of reproductive fluids as additives for the culture media in pig IVP does not improve reproductive performance of recipient mothers but could mitigate the impact of artificial procedures in the offspring.

Modelling Particle Transport and Deposition in the Human Healthy and Stented Tracheobronchial Airways.

The main goal of this study is the quantification of the particle transport and deposition within the human airways during light, normal and exercise breathing conditions using the computational fluid dynamics. In particular we presented a comparison between healthy and stented airways. The considered tracheobronchial model is based on the Weibel symmetric model in which we have inserted the Dumon prosthesis at different locations and on the CT-based geometries of a healthy and a stented airway. The results indicate an important redistribution of the particle deposition locations. Local overdoses can be found in the proximal regions of the prostheses, independently of the breathing conditions, of the particle size and of the considered geometry. The presented work is aimed to contribute to the understanding of the particle deposition in the human lung and to improve drug-aerosol therapies. For patients that underwent airways reconstructive surgery, it can give detailed information about the deposition efficiency and it may help targeting specific airways regions.

Lobectomías robóticas y cáncer de pulmón. Experiencia inicial en nuestro centro / Robotic lobectomies and lung cancer. Initial experience in our center

Objetivo: Analizar la seguridad y factibilidad en términos de resultados obtenidos en las primeras lobectomías robóticas realizadas en nuestro centro. Metodología: Estudio prospectivo desde mayo hasta diciembre de 2021 en 13 pacientes (11 hombres y 2 mujeres, edad media 59 años) con carcinoma de pulmón en estadios precoces tributarios de lobectomía robótica.Se utilizó el sistema da Vinci Xi con cuatro puertos y uno asistente. Resultados: Se realizaron 13 lobectomías robóticas. La conversión a cirugía videoasistida fue necesaria en 2 pacientes (15,4%). Se produjeron complicaciones en 3 pacientes (23%). La mediana de tiempo quirúrgico fue180 minutos [IQR 150-210]. La mediana de estancia hospitalaria fue de 4 días [IQR 3 - 6]. La mediana de duración del drenaje pleural fue de 4 días [IQR3 - 6]. La histología predominante fue carcinoma epidermoide en5 pacientes (39%). La media de ganglios linfáticos resecados fue de 15 (IC 95%: 11 - 19) y la de estaciones ganglionares de 5 (IC 95%: 4 - 5). No hubo mortalidad postoperatoria. El estadio postquirúrgico fue IA2 en 4 pacientes (31%), IB en 3 (23%), IIB en 2 (15%), y IIIA en 1 (7%). No se establecen diferencias estadísticamente significativas entre el IMC, el lóbulo resecado y la presencia de complicaciones (p = 0,5; p = 0,2), ni entre el número de ganglios resecados/número de estaciones ganglionares, y el estadio tumoral (p = 0,4; p = 0,9). Conclusiones: La lobectomía robótica con linfadenectomía hiliomediastínica es factible y segura. Es necesaria mayor experiencia y seguimiento a largo plazo para una adecuada evaluación de los resultados postoperatorios, la eficacia oncológica, y la comparación con las vías de abordaje convencionales. (AU)

Objectives: analyze the safety and feasibility in terms of results obtained in the first robotic lobectomies performed in our center. Method: prospective study from May to December 2021 in 13 patients (11 men and 2 women, mean age 59 years) with lung carcinoma in early stages requiring robotic lobectomy. The da Vinci Xi system was used with four ports and one assistant. Results: 13 robotic lobectomies were performed. Conversion to video-assisted surgery was necessary in 2 patients (15.4%). Complications occurred in 3 patients (23%). The median surgical time was 180 minutes [IQR 150-210]. The median hospital stay was 4 days [IQR 3 - 6]. The median duration of pleural drainage was 4 days [IQR3 - 6]. The predominant histology was squamous cell carcinoma in 5 patients (39%). The mean number of lymph nodes resected was 15 (95% CI: 11 - 19) and the number of lymph nodes resected was 5 (95% CI: 4 - 5). There was no postoperative mortality. The postsurgical stage was IA2 in 4 patients (31%), IB in 3 (23%), IIB in 2 (15%), and IIIA in 1 (7%). No statistically significant differences were established between BMI, the resected lobe and the presence of complications (p = 0.5; p = 0.2), nor between the number of resected lymph nodes/number of lymph node stations, and the tumor stage ( p = 0.4; p = 0.9).Conclusions: robotic lobectomy with hiliomediastinal lymphadenectomy is feasible and safe. Greater experience and long-term follow-up are necessary for an adequate evaluation of postoperative results, oncological efficacy, and comparison with conventional approaches. (AU)

Evaluation of a cushioned method for centrifugation and processing for freezing boar semen.

The purpose of this investigation was to evaluate the use of an iodixanol cushion during centrifugation on sperm recovery and yield after centrifugation (sperm recovery, sperm motility, viability, membrane lipid disorder, acrosome reaction and ROS generation); and to investigate how this procedure affects sperm function after freezing-thawing (sperm motility, membrane lipid disorder, acrosomal status and homologous in vitro penetration test). The sperm-rich fractions from fertile boars were centrifuged under two centrifugation régimes: 800xg for 10min (standard method) and 1000xg for 20min with an iodixanol (60% w/v) cushion at the bottom of the centrifuge tubes (Cushion method). The highest recovery was achieved using the cushion method (sperm loss for cushion method was 0.50%+/-0.18 versus 2.97%+/-0.43 for standard method, P<0.01) and sperm quality was not significantly affected by the centrifugation régime. The motion parameters (% progressive motility, % motility, VCL, VSL, VAP, ALH, BCF, P<0.05) of frozen-thawed samples showed higher values using the standard method. However, a higher number of viable spermatozoa with lower lipid disorders were found in spermatozoa processed with the cushion method. The in vitro penetration assay showed that the individual boar influenced the parameters studied but there were no differences between the two centrifugation régimes used. Our results support the hypothesis that the proportion of sperm loss in frozen-thawed semen was significantly influenced by the centrifugation régime. Therefore, the iodixanol cushion method is a suitable tool for cryopreservation of boar semen in order to reduce sperm loss without affecting sperm quality.

Boar sperm with defective motility are discriminated in the backflow moments after insemination.

During insemination, a large number of spermatozoa are deposited in the female genital tract, but a very low percentage is able to colonize the site of fertilization. The influx of neutrophils into the uterine lumen and semen reflux (backflow) are known mechanisms that decrease the number of spermatozoa within the uterus. No report has attempted to ascertain whether the backflow is a random or selective process of the spermatozoa. In this work, sows were inseminated using two populations of spermatozoa in the same proportion: (1) unstained spermatozoa with high motility and (2) stained spermatozoa with low, medium, or high motility. Volume, number, and percentage of stained spermatozoa were evaluated in the backflow (collected at 0-15, 16-30, and 31-60 minutes after insemination). This article provides evidence that (1) the motility characteristics of the spermatozoa do not influence the percentage of sows with backflow, the volume and number of spermatozoa in the backflow; (2) the discarding of spermatozoa in the backflow is not specific during the first moments after insemination (0-15 minutes), whereas later (16-60 minutes), spermatozoa with defective motility (low and medium groups) are discarded in a higher proportion than high group in the backflow ([16-30 minutes: low, 85.13 ± 4.32%; medium, 72.99 ± 5.05%; and high, 54.91 ± 2.38%; P < 0.0001; 31-60 minutes: low, 87.16 ± 6.01%; medium, 87.02 ± 4.01%; and high, 59.35 ± 2.86%; P = 0.001]). Spermatozoa with poor motility are discarded in the backflow probably as a selective process, on the part of the female genital tract or as a result of the intrinsic low spermatozoa motility.

Lectin histochemistry during in vitro capacitation and acrosome reaction in boar spermatozoa: new lectins for evaluating acrosomal status of boar spermatozoa.

Six peroxidase (HRP)-conjugated lectins have been used to analyze the distribution of carbohydrates in ejaculated boar spermatozoa during in vitro capacitation and acrosome reaction in air-dried preparations. The membranes of boar spermatozoa were positive to WGA and Con-A in the acrosome, middle piece and principal piece. PNA labelled the acrosomal region. DBA, UEA-I and LTA bound weakly or not to the spermatozoa. The lectin labelling pattern did not change during the in vitro capacitation. A diminution in the proportion of spermatozoa with acrosome positive to lectins PNA, WGA and Con-A was observed after coincubation with homologous immature oocytes. A positive correlation existed between the percentages of lectins bound to spermatozoa and the triple stain technique. The results show that peroxidase-conjugated lectins may be useful in determining acrosomal integrity of boar spermatozoa during in vitro capacitation and acrosome reaction.

Prediction of porcine semen fertility by homologous in vitro penetration (hIVP) assay.

A field trial was conducted to compare the fertility predicting capacity of different sperm assays applying classical semen analysis, sperm function and the homologous in vitro penetration test (hIVP) to 60 ejaculates from four boars collected over a period of 15 weeks. No differences were found between the groups of fertility (Low Fertility: < 20%; Intermediate: 40-60% and High: > 80%) for sperm-rich fraction volume collection, sperm concentration, total sperm number, cationic contents in seminal plasma and ATP concentration. Partial differences were found in the parameters of motility, normal morphology, normal apical ridge (NAR), viability with eosin-nigrosin stain, hypo-osmotic swelling test (HOS), osmotic resistance test (ORT) and functional membrane integrity (with carboxyfluorescein diacetate, DCF). These parameters would be useful for detecting sperm with poor fertility, but they are not precise enough to discriminate an ejaculate with higher fertility than the herd median. Only the penetration percentage (10.24 +/- 1.45 vs. 55.13 +/- 3.35 vs. 84.72 +/- 1.73) and sperm number per oocyte (1.29 +/- 0.07 vs. 11.29 +/- 1.79 vs. 25.86 +/- 1.43) in a hIVP system were parameters with a predictive capacity to discriminate between the three fertility groups. Consequently, hIVP was found to be the best seminal assay and it may improve the in vitro assessment of sperm fertilizing ability.

Effect of co-culture of porcine sperm and oocytes with porcine oviductal epithelial cells on in vitro fertilization.

This study was designed to determine the effect of co-culture with porcine oviductal epithelial cell (POEC) monolayers on in vitro fertilization of pig oocytes. The in vitro penetrability of mature (experiment 1) or immature (experiment 2) oocytes was studied in presence or absence of POEC during IVF with fresh semen. In experiment 3, boar and POEC effects were analyzed but in this case with frozen-thawed spermatozoa. In experiment 4, the spermatozoa were pre-incubated before IVF with or without POEC in order to assess their effect on IVF sperm-related parameters. In experiment 5, the effect of POEC was studied by co-culturing them with oocytes before IVF to determine if monospermy was improved. The results showed that high sperm concentration and POEC increase oocyte penetrability (P<0.01) and decrease monospermy rate (P<0.01), in both mature and immature oocytes (P<0.01) with fresh semen and a 18 h culture time. With frozen semen was detected a boar and POEC effect (P<0.01) on penetration rate. The sperm pre-culture 2 h with POEC also resulted in an increase of sperm penetration in terms of number of sperm per oocyte (P<0.01) and this treatment did not increase monospermy when contact time between gametes was limited to 6 h although monospermy was higher when POEC were present during IVF. Finally, exposure of oocytes to POEC for 4 h before IVF facilitated monospermic penetration to over 70% (P<0.01). In conclusion, the use of POEC in porcine IVF systems provides the possibility of working with low sperm concentrations and the effect of POEC on monospermy depends on sperm concentration, boar and contact time between gametes. Moreover, the exposure of oocytes to POEC before IVF improves the rate of monospermy.

Sperm factors related to in vitro penetration of porcine oocytes.

This study was designed to evaluate the relationship between sperm factors and penetration capacity in an in vitro system with immature porcine oocytes. The sperm parameters evaluated in 145 ejaculates were volume, sperm concentration, total cells in the ejaculate, ATP content, morpho-anomalies, percentage of motile sperm cells, forward progressive motility (FPM), acrosome status (NAR), hypo-osmotic swelling test (HOS), osmotic resistance test (ORT), eosin-nigrosin viability stain and sperm membrane integrity (DCF). Porcine oocytes (a total of 8,736) were used to evaluate the capacity of the different sperm assays to predict penetration. Many parameters were found to be related to in vitro penetration ability; all conventional semen parameters, except sperm concentration and eosinnigrosin staining, were significantly better in high (>75%) than in low penetration rates (<75%). When the ejaculates were preselected the number of significantly related parameters was lower. When studying all conventional semen parameters through a stepwise multiple linear regression analysis of seminal measurements, up to 72.3% of total variance of the penetration rate could be predicted. However, as many as 4 parameters were needed (FPM in fresh semen, folded tail, NAR in post-treatment semen and DCF) for accurate prediction. On the other hand, the multiple logistic regression needed 7 parameters to discriminate 83.96% of the cases correctly. In summary, the results from the present study showed that almost all studied parameters were significantly different for predicting penetration process attained or failed, but most of them were correlated together. These findings emphasize the complexity of sperm functions and the difficulty of assessing the fertilizing ability.

In vitro penetration assay of boar sperm fertility: effect of various factors on the penetrability of immature pig oocytes.

The present study was designed 1) to examine the influence of cumulus cells, ovary storage time and oocyte size on the penetrability of immature pig oocytes, and 2) to investigate the effect of 2 methods of treating the semen from different boars on the inter-assay variability of homologous in vitro penetration tests of boar sperm fertility. In Experiment 1, cumulus oocyte complexes, oocytes with spontaneous loss of the cumulus cells during collection, and oocytes mechanically stripped of cumulus cells were used. No differences were observed in oocyte penetrability among the 3 types of oocyte, although mechanical removal of the cumulus caused an increase (P < 0.005) in the degeneration rate compared with the other oocyte types. In Experiment 2, the oocytes were recovered from ovaries kept in PBS (30 degrees C) for 2, 4 or 6 h after slaughter of prepuberal gilts. Ovary storage did not modify the penetrability of oocytes but increased (P < 0.02) their degeneration rates. In Experiment 3, the diameters of fresh oocytes were determined after co-incubation with spermatozoa. They were classified into 4 groups according to diameter: A) < 105 microm, B) 105-115 microm, C) 116-120 microm and D) > 120 microm. Oocytes from Groups C and D exhibited higher (P < 0.05) penetrability than oocytes from the other groups. In Experiment 4, stored, diluted spermatozoa from 4 boars were pretreated by centrifugation at 50 x g for 3 min and subsequent concentration of the supernatants at 1,200 x g for 3 min. The pellets were treated (washed twice and preincubated for 40 minutes) before co-incubation with immature oocytes or used directly as untreated samples (unwashed and non-preincubated). A boar effect (P < 0.001) was evident for the parameters of in vitro penetration, independently of sperm treatment. When the oocytes were inseminated with untreated spermatozoa, the effects of the replicate and the boar-by-replicate interaction on the variability in oocyte penetrability were not significant. The results of this study indicate that the use of standardized immature pig oocytes and stored untreated, diluted spermatozoa can provide a useful method for optimizing the homologous in vitro penetration (hIVP) assay of boar fertility.

Sperm concentration influences fertilization and male pronuclear formation in vitro in pigs.

To study the effect of sperm concentration on the results of pig in vitro fertilization (IVF), 313 oocytes recovered from oviducts of prepubertal gilts after induction of ovulation were used. After capacitation, the number of live spermatozoa in the fertilization dishes was adjusted to 3 x 10(5), 6 x 10(5) and 12 x 10(5) cell/ml. After 4 hours of co-culture in TCM-199, the oocytes were pippeted to remove cumulus cells and the excess spermatozoa around the zona pellucida, and were transferred to fresh TCM-199 for another 12/14 hours. The results showed that 6 x 10(5) spermatozoa/ml is the optimum concentration for this system; the percentage of fertilized ova (71.6%) was not different from the best (76.8%), that was obtained with the highest concentration, and the percentage of monospermy (62.3%) was not different from the best (68.1%), that was obtained with the lowest concentration. The percentage of spermatozoa that reached the pronuclear stage increased while sperm concentration was decreased. The percentage of spermatozoa at the decondensed stage was decreased when the sperm concentration increased.

Evaluation of boar spermatozoa penetrating capacity using pig oocytes at the germinal vesicle stage.

We evaluated the ability of immature pig oocytes (at germinal vesicle stage) to detect differences in the in vitro penetration rates of boar spermatozoa. In Experiment 1, immature and ovulated oocytes (n=303) were exposed to capacitated boar spermatozoa to determine if the penetrability of immature pig oocytes was comparable to that of ovulated oocytes. The percentages of penetrated oocytes and the mean number of spermatozoa per oocyte were similar for immature (88.82 and 7.42+/-0.41) and ovulated oocytes (90.97 and 7.95+/-0.34, respectively). In Experiment 2, immature oocytes (n=1230) were inseminated with semen from 2 boars (A and B) with satisfactory semen characteristics to establish the variability of in vitro penetrating capacity between the boars. Semen was examined for motility, movement quality, acrosome integrity and plasma membrane integrity at various stages of the in vitro procedure. Although the sperm evaluation results were similar between boars, Boar A exhibited a significantly higher (P<0.001) penetration rate (91.49%) and number of spermatozoa penetrated per oocyte (5.90+/-0.25) than Boar B (52.87% and 2.03+/-0.12, respectively). Increasing the sperm concentration at insemination from 1 x 10(6) to 10 x 10(6) cells/ml resulted in an increased penetrating capacity for both boars, and the differences in the number of spermatozoa per oocyte between boars also increased. These results indicate that immature pig oocytes can be used in a homologous in vitro fertilization assay, and that despite similarities in semen characteristics a significant boar effect is evident for parameters of in vitro penetration of oocytes.

In vitro fertilization of pig oocytes after different coincubation intervals.

The effects of gamete coincubation time on porcine in vitro fertilization for 4, 6 or 8 hours in Trial 1 or for 1, 2, 3 or 4 hours in Trial 2 were studied. The 876 oocytes were recovered from oviducts of prepubertal gilts. Ovulation was induced. Excessive spermatozoa attached to zona pellucida were removed by pippeting after coincubation (1 to 8 hours). Optimum results were obtained after 3 to 4 hours of coincubation, when 23 to 29% of the oocytes were fertilized by a single spermatozoa. Shorter intervals of coincubation were characterized by reduced percentages of fertilized oocytes and longer intervals of coincubation by increased rates of polyspermic fertilization. The employed sperm concentration was deliberately high (2 x 10(6) sperm/ml). The results show that a coincubation time of 4 hours may be optimal for pig in vitro fertilization. Under these assay conditions, modification of other factors such as sperm concentration, medium volume and physiological environment may increase the percentage of monospermic fertilization.

Influence of zinc intake on hepatic lipid peroxidation and metallothioneins in alcoholic rats: relationship to collagen synthesis.

Hepatic lipid peroxidation, metallothioneins, collagen and proline hydroxylase activity were investigated in 16 ethanol-fed rats and in 16 control animals. The rats were further divided into three groups to receive either a standard diet, a zinc-deficient diet or a zinc-supplemented diet. The animals were sacrificed at week 12 of the experiment for histological and biochemical assessments. Hepatic tissue examination indicated that oral zinc supplementation was associated with a decrease in lipid peroxidation, collagen deposition and proline hydroxylase activity together with an increase in metallothionein concentration in alcoholic rats. There were no significant differences in lipid peroxidation in the control group in relation to the diet. Zinc supplementation was associated with increased concentrations of hepatic metallothioneins together with decreased concentrations of proline-hydroxylase and collagen but to a lesser degree than in alcoholic animals. These results indicate that zinc is an efficient hepato-protective agent against lipid peroxidation in alcoholic rats and its effect may be, in part, mediated by the activation of metallothionein synthesis. Also, lipid peroxidation may be related to changes in hepatic collagen synthesis.

[The hospital nursing discharge form. Establishing and validation of a standard formate]. / Alta de enfermería hospitalaria. Implantación y validación de un formato estándar.

The purpose of this article is to describe the design, application and validation process for a new hospital nursing medical discharge form. This process has three phases: FIRST PHASE: Redesigning the Document. In 1996, as a response to growing demands as well as the need to adapt to the requirements of data processing, all nursing documents in all hospital nursing files were updated following the recommendations of the Technical Commission. SECOND PHASE: Initial Application and Validation. The medical discharge form prepared in phase one was applied during the first trimester of 1997. The parties involved agreed to test this form until the end of the year in order to come to a consensus regarding its structure and content while at the same time determining its degree of comprehension and usefulness. THIRD PHASE: Editing and Final Format. The results of these analyses, together with revisions of criteria included in the NMDS and from the Conference on Hospital Discharge Abstract System, made it possible to draw up the final draft of this form which include nursing discharge criteria in the evaluation section. A pilot test was carried out in five hospital units to determine the validity of this form according to the same criteria of comprehension and usefulness. The results indicate a recommendation to eliminate the sections of medical diagnosis and medication upon discharge while to maintain the identification of the patient, the summary of his/her stay in the center, the description of the patient's case upon discharge and the treatment plan.