Developmental potential of vitrified holstein cattle embryos fertilized in vitro with sex-sorted sperm

In vitro fertilization (IVF) is a feasible way to utilize sex-sorted sperm to produce offspring of a predetermined sex in the livestock industry. The objective of the present study was to examine the effects of various factors on bovine IVF and to systematically improve the efficiency of IVF production using sex-sorted sperm. Both bulls and sorting contributed to the variability among differential development rates of embryos fertilized by sexed sperm. Increased sorting pressures (275.8 to 344.75 kPa) did not have a significant effect on the in vitro fertility of the sorted sperm; neither did an extended period of 9 to 14 h from semen collection to sorting. As few as 600 sorted sperm were used to fertilize an oocyte, resulting in blastocyst development of 33.2%. Postwarming of vitrified sexed IVF embryos resulted in high morphological survival (96.3%) and hatching (84.4%) rates, similar to those fertilized by nonsexed sperm (93.1 and 80.6%, respectively). A 40.9% pregnancy rate was established following the transfer of 3,627 vitrified, sexed embryos into synchronized recipients. This was not different from the rates with nonsexed IVF (41.9%, n = 481), or in vivo-produced (53.1%, n = 192) embryos. Of 458 calves born, 442 (96.5%) were female and 99.6% appeared normal. These technologies (sperm sexing-IVF-vitrification-embryo transfer) provide farmers, as well as the livestock industry, with a valuable option for herd expansion and heifer replacement programs. In summary, calves were produced using embryos fertilized by sex-sorted sperm in vitro and cryopreserved by rapid cooling vitrification.

351 INSEMINATION OF HOLSTEIN HEIFERS WITH SEXED SPERM PROCESSED WITH OR WITHOUT EGG YOLK IN THE GLYCEROL-CONTAINING FREEZING MEDIUM

Preparation of media for use in processing sorted sperm is laborious and expensive. The objective was to determine whether pregnancy rates in heifers following AI of frozen/thawed X chromosome-bearing sperm were equivalent for sperm processed for cryopreservation using glycerol-containing medium with or without egg yolk. X chromosome-bearing sperm from each of two Holstein bulls were isolated on the basis of DNA content using a flow cytometer. Sorted sperm were collected in 50-mL plastic tubes containing 2-mL of 20% egg yolk-TRIS extender without glycerol until each tube contained 12.4 mL and approximately 12 million sperm. Sorted sperm were cooled (5�C) over 90 min before the addition of 12% glycerol-containing TIS medium with or without 20% egg yolk, as two equal volumes (6.5 mL) at 15-min intervals. Tubes containing 25 mL were centrifuged at 850g for 20 min (5�C). After the supernatant was removed, sperm pellets within treatments and bulls were pooled. Sperm concentration was adjusted to 10 � 106/mL with medium containing 6% glycerol and 20% egg yolk-TRIS. Sorted sperm were packaged and frozen in 0.25 mL-coded straws on freezing racks in LN2 vapor. Straws from each bull-treatment combination were equally packaged in goblets to assure random use. Post-thaw sperm progressive motility, determined with time-lapse photography ('track motility'), was 44% for non-egg yolk and 43% for 20% egg yolk-glycerol-containing media. Nonsynchronized Holstein heifers (n = 119) were inseminated 4, 12, or 24 h after observed standing estrus. Sperm were deposited into the uterine body anterior to the internal cervical os. Approximately 1 month after insemination, pregnancy was determined using ultrasound. Data were subjected to ANOVA. The pregnancy rate and 95% confidence interval for sorted sperm processed with non-egg yolk-glycerol-containing medium was 56% (49-73; n = 59), and 55% (38-62; n = 60) for the 20% egg yolk-glycerol-containing medium (P > 0.1). Bull or inseminator effects on pregnancy rates were not significant (P > 0.01). Pregnancy rates as a function of time of insemination at 4, 12, or 24 h relative to observed estrus were 62% n = 65; 48% n = 48; and 50% n = 6, respectively (P > 0.1). Even though the scope of the field trial was limited, omission of egg yolk from the glycerol-containing medium did not adversely affect pregnancy rates. Preparation of non-egg yolk-glycerol-containing medium greatly reduces associated time, labor, and expense. This study also resulted in quite acceptable pregnancy rates with insemination doses of 2 � 106 total sorted frozen/thawed sperm.

347 ARTIFICIAL INSEMINATION OF LACTATING HOLSTEIN COWS WITH SEXED SPERM

The recommended use of sexed sperm has been limited to heifers. The objective of this field trial was to determine pregnancy rates in lactating dairy cows following artificial insemination of 2 or 10 � 106 sexed or 10 � 106 unsexed frozen/thawed sperm. Sperm were separated into X chromosome-bearing populations at rates of 3000-5000/s, on the basis of DNA content, with a flow cytometer/sperm sorter operating at 40 psi and using 150 mW of laser intensity. Sperm were sorted, collected and cryopreserved in a Tris-based medium. Holstein cows, averaging 2.4 lactations (range: 1-9), were presynchronized with prostaglandin F2� (PGF)2�; (25 mg) i.m. at 40-58 days in milk (DIM) (average, 44 days). A second dose of PGF2� (25 mg) i.m. was administered 14 days later. All cows were screened with ultrasound 14 days later, and those with normal ovarian and uterine status were used for this study. Qualifying cows received 100 �g gonadotropin-releasing hormone (GnRH) i.m. (average, 72 DIM) and 25 mg PGF2� i.m. 7 days later, and then 100 �g GnRH i.m. 2 days after the prostaglandin. Cows (n = 172) were fixed-timed inseminated 16-19 h after the last GnRH treatment, balanced over three sperm insemination treatments, two Holstein bulls, and two inseminators. Both 32-day pregnancy and 60-day fetal sex were determined using ultrasound. Cows carrying fetuses identified as dying at the 32-day ultrasound check were considered not pregnant. Data were subjected to ANOVA. Effects of sperm treatment, bulls, inseminators, and subsequent interactions on pregnancy rate were not significant (P > 0.05). The 32-day pregnancy rate and 95% confidence interval for 10 � 106 unsexed, 10 � 106 sexed, and 2 � 106 sexed inseminates were 55.6 (42.5-68.6), 43.9 (31.6-57.0), and 40.4% (28.4-53.6), respectively. Additionally, DIM or cow parity did not affect pregnancy rate (P > 0.05). Fetal death (<32 days) for unsexed inseminates was 5.5% (two pregnancies) compared to 9.5% (four pregnancies) for pooled sexed inseminates (P > 0.05). There were four confirmed pregnancies of sexed sperm that also aborted between Days 32-60. Fetal sex ratio was significantly altered (P < 0.05) for sexed (93% female fetuses) compared to unsexed (52% female fetuses) inseminates. Pregnancy rate in these selected lactating cows inseminated with sexed sperm was not significantly lower (P > 0.05) than that for unsexed sperm. However, these results should be viewed cautiously due to the limited numbers of cows used. Successful use of sexed sperm in dairy cows, which approached an elective waiting period of 80 DIM, was achieved with cows that were selected for reproductive status prior to insemination.

New molecular defects in the gamma subdomain of fibrinogen D-domain in four cases of (hypo)dysfibrinogenemia: fibrinogen variants Hannover VI, Homburg VII, Stuttgart and Suhl

Four new molecular abnormalities in the gamma subdomain of the D domain elucidated in three unrelated thrombophilic patients and in one asymptomatic case of hypofibrinogenemia are reported: fibrinogen Suhl, gamma 326, Cys-->Tyr, fibrinogen Hannover VI, gamma 336 Met-->Ile, fibrinogen Stuttgart, gamma 345, Asn-->Asp and fibrinogen Homburg VII, gamma 354,Tyr-->Cys. In all cases, fibrin polymerization in plasma is impaired. In the case of fibrinogen Suhl, there was a normalization of fibrin polymerization in plasma at higher Ca(2+) concentration. The protective effect of Ca(2+) on plasmic degradation of fibrinogen was incomplete with all three variants. The fibrinogen molecules in variants Homburg VII and Suhl contain covalently bound albumin. Fibrin clot structure was abnormal in case of variant Homburg VII, with finer and more branched fibers forming a less porous clot. Experimental data indicate possible effects of the molecular abnormalities on Ca(2+)-binding, D-E interaction and lateral association of protofibrils.

In vitro hemocompatibility testing of biomaterials according to the ISO 10993-4

The development of synthetic materials, textured polymers and metals and their increasing use in medicine make research of biomaterials' hemocompatibility very relevant. Problems arise from the polymorphism and diversity of the different materials, the static and dynamic test models and the patients' individual biologic factors. First, methods, models, tests as well as preanalytical factors have to be standardized according to the current knowledge in medicine laid down in the ISO 10993 part 4. The routine controls used in clinical chemistry and hematology have to be performed. Information about normal ranges (mean value, standard deviation, 95% confidence interval) should be provided. Tests have to be performed within a minimal delay of usually 2 h since some properties of blood change rapidly following collection. Various conditions (depending on the wall shear rate) were simulated within the centrifugation system and a Chandler system. Qualities and aspects of hemocompatibility such as platelet activation, oxidative burst, hemolysis, fibrinolysis, fibrin formation, generation of thrombin, contact activation, and complement activation were analysed and the results were entered non-dimensionally into a non-dimensional score system, where 0 points stand for the best and 65 points for the worst evaluation. We found a good correlation between the total score and contact activation, thrombin generation and leukocyte activation in a low shear stress system and a good correlation between the total score and thrombin generation, hemolysis and platelet activation in the high shear stress system. Further on the effect of additives and sterilization procedures can be measured. The concepts presented underline the relevance/importance of an efficient diagnostic approach to hemocompatibility that takes account of clinical and socio-economic concerns.

[Fechtner syndrome. A rare differential Alport syndrome diagnosis]

In this article, we report on a family in which five examined members showed clinical signs of Fechtner syndrome, a condition which consists of hearing loss (49%), macro-thrombocytopenia (100%), leukocyte inclusion bodies (100%), eye anomalies (54.3%), and nephritis (38.7%). Hearing loss in Fechtner syndrome appears to be sensorineural with the higher frequencies primarily affected. One aim of the present report was to work out the clinical appearance of hearing loss compared to hearing loss in Alport's syndrome. The most striking difference between hearing loss in Fechtner syndrome and that in Alport's syndrome was that the vast majority of hearing disorders in the latter occur in male patients, which is not the case in Fechtner syndrome. Hearing loss in Fechtner syndrome develops from the second decade of life and progresses slowly with several episodes of sudden deafness.

[Late onset of heparin-induced thrombocytopenia with recurrent arterial thromboses and amputation]

HISTORY

An 80-year-old woman had been hospitalized in a psychiatric clinic where, on the 22nd day, she sustained a fracture of the neck of the left femur, which was treated by internal screw fixation. The postoperative course was at first without complication. But 9 days postoperatively her platelet count had fallen to 59,000/microliter. As heparin induced type II thrombocytopenia (HIT II) was suspected, the thrombosis prophylaxis with low-molecular heparin was replaced by sodium danaparoid (twice 750 units subcutaneously). Despite this, ischaemia of the right lower leg developed and required amputation. On the following day the left lower leg and foot also became ischemic, where upon she was admitted to the author's hospital (37 days after her admission to the psychiatric clinic).

ADMISSION FINDINGS

The patient was in a reduced general condition (body-mass index 19.5 kg/m2). She was disoriented as to place and time. Her blood pressure was 140/80 mmHg, her pulse irregular with a ventricular rate of 100/min. The skin below the middle of the left lower leg was cold and livid and the pedal pulses were not palpable.

LABORATORY TESTS

Haemoglobin content was 9.7 g/dl, the white cell count 9,200/microliter, and platelet count 54,000/microliter. Electrolytes and creatinine were within normal limits.

TREATMENT AND COURSE

Thrombendarterectomy was performed once via the left groin under danaparoid anticoagulation. There was no re-occlusion and the patient was able to walk again.--It was ascertained subsequently, she had already been given ordinary heparin in the psychiatric clinic for 20 days. Her platelet count of around 70,000/microliter returned to normal even though heparin administration was continued.

CONCLUSION

A reduction in platelet count by more than half during heparin treatment suggests heparin-induced thrombocytopenia, in which case heparin should be discontinued at once. In high-risk patients adequate treatment should be initiated with other anticoagulants even before the occurrence of thromboembolism.

Development of a novel, N-terminal-proBNP (NT-proBNP) assay with a low detection limit

A novel, highly sensitive and specific N-Terminal-proBNP (NT-proBNP) assay based on a sandwich format has been developed. The assay time is below 2 hours and no extraction process is needed. The calibration curve covers a NT-proBNP concentration range from 0 pmol/L up to 600 pmol/L. The analytical detection limit of the assay was estimated to be 2.7 pmol/L (3 SD). The intra-assay coefficient of variation is 5.7% (at 50 pmol/L) and 6.1% (at 250 pmol/L), while the inter-assay CVs are 15.8% (15 pmol/L) and 8.2% (250 pmol/L). There is no significant interference by bilirubin (up to 900 mumol/L), haemoglobin (up to 10 g/L), rheumatoid factors (up to 975 IU/mL), triglycerides (up to 20.5 mmol/L), biotin (up to 50 micrograms/L), digoxin (up to 100 micrograms/L) and digitoxin (up to 200 micrograms/L). The analyte NT-proBNP is fully stable in whole blood over 3 days and in EDTA-plasma over 24 hours. This good stability of NT-proBNP compared to other less stable natriuretic peptides is a significant advantage and a main prerequisite for a routine diagnostic marker. Preliminary results of using this new assay in clinical studies for diagnosing and monitoring left ventricular dysfunction demonstrate that there is a significant gain in diagnostic validity.

Effects of polysulfonate derivative (GL 522-Y-1) on coagulation in vitro and thrombosis in vivo

We have investigated the influence of a polysulfonate derivative - GL 522-Y-1 - on platelet-induced thrombin generation time, platelet adhesion to siliconized glass, platelet aggregation induced by collagen and ADP, on aPTT, PT and TT in vitro and studied its antithrombotic effect in an animal model of thrombosis in vivo. In vitro, GL 522-Y-1 caused inhibition of ADP- and collagen-induced aggregation. In a dose-dependent manner this compound inhibited PITT, aPTT, and PT. GL 522-Y-1 did not prolong thrombin time. GL 522-Y-1 inhibited in vivo the laser-induced thrombus formation after intravenous and oral administration. On the basis of its unique antithrombotic properties, GL 522-Y-1 seems to open a new pathway in the field of antithrombotics.

Effects of a supersulfated low molecular weight heparin (IK-SSH) on different hemostatic parameters

In a phase I trial effects of a new supersulfated low molecular weight heparin (IK-SSH) on different hemostatic parameters were investigated in healthy volunteers. Parameters studied were activated partial thromboplastin time (aPTT), thrombin time, Heptest, anti-activated factor II (anti-FIIa) and anti-activated factor X (anti-FXa) activity, platelet adhesion, platelet count, platelet-induced thrombin generation time (PITT), bleeding time, antithrombin III, fibrinogen and several safety parameters. After single intravenous (i.v.) injections of IK-SSH (0.14, 0.33 and 0.66 mg/kg) aPTT, Heptest and PITT were strongly and dose-dependently prolonged. After ascending subcutaneous (s.c.) doses of IK-SSH (0.33, 0.66 and 1 mg/kg) aPTT, Heptest and PITT were prolonged in a dose-dependent manner. Repeat s.c. injections of 1 mg/kg IK-SSH for 5 days markedly prolonged aPTT, Heptest and PITT. No cumulative effects were observed. Anti-FIIa and anti-FXa activity were not or only slightly increased. Bleeding time, thrombin time and platelet adhesion were not significantly changed after i.v. and s.c. injections of IK-SSH. However, tissue factor pathway inhibitor (TFPI) concentration was markedly increased after each injection of IK-SSH and returned to the preinjection value 24 h later. IK-SSH prolongs aPTT, Heptest and PITT in a similar manner as other low molecular weight heparins but without significantly affecting thrombin time, FIIa and FXa activity. The release of TFPI may well be responsible for the prolongation of aPTT, Heptest and PITT. IK-SSH may be further developed as an antithrombotic agent.

Integrated cardiovascular function in the conscious streptozotocin-diabetic deoxycorticosterone-acetate-hypertensive rats

Blood pressure, heart rate, and left ventricular function were measured in conscious diabetic Sprague-Dawley rats subjected to 5 weeks of deoxycorticosterone acetate (DOCA) treatment which was started 1 week following intravenous injection of streptozotocin (STZ) (60 mg/kg) to induce diabetes mellitus. It was found that chronic administration of DOCA in nondiabetic animals caused an increase in blood pressure and functional parameters of left ventricle, and a decrease in heart rate and plasma insulin levels. Normotensive diabetic rats exhibited hyperglycemia, hypoinsulinemia, and a lower body weight as compared with control animals but did not show significant abnormalities in cardiovascular function. DOCA-hypertensive STZ-diabetic rats had similar hyperglycemia, milder hypoinsulinemia, and a significantly lower rate of left ventricular relaxation and systolic blood pressure compared with the nondiabetic DOCA-hypertensive animals. It is concluded that the addition of DOCA hypertension to intact 6-week STZ-diabetic Sprague-Dawley rats results in the occurrence of cardiac dysfunction.

The pathogenesis of DOCA-salt hypertension

Deoxycorticosterone acetate (DOCA) is an agent commonly used to induce hypertension in experimental animals. This form of hypertension is dependent on altered regulation of central pressor mechanisms including the brain renin-angiotensin system. Additionally, there are characteristic changes involving the cardiovascular system and baroreflex responses. This review will discuss aspects of the pathogenesis of DOCA hypertension and the effect of various antihypertensive agents on the development of this form of hypertension.

Measurement of cardiac left ventricular pressure in conscious rats using a fluid-filled catheter

A fluid-filled catheter consisting of 100 cm of PE50 polyethylene tubing welded to 7 cm of PE10 polyethylene tubing (PE50/PE10) was constructed for the purpose of measuring the rate of left ventricular pressure development (+dP/dt) in conscious, freely moving rats. Prior to in vivo experiments, four PE50/PE10 catheters were randomly selected, and their natural frequencies and damping ratios were determined using a square wave impact. The mean (n = 4), natural frequency of these catheters was shown to be 35.0 +/- 5.5 Hz, and the mean damping ratio was 0.83 +/- 0.10. Natural frequency plotted against increasing PE50 tubing length was shown to have a slope of -0.44 Hz/cm with a correlation coefficient of 0.99. The effect of the 7-cm PE10 tubing segment on the catheter damping ratio was also demonstrated. One of the four PE50/PE10 type catheters exhibited a damping ratio of 0.74 +/- 0.09. When the 7-cm PE10 tube was removed, the damping ratio was reduced to 0.31 +/- 0.04. Left ventricular +dP/dt obtained in conscious rats with a PE50/PE10 catheter (n = 7; 6300 +/- 300 mmHg/sec) was significantly less than the +dP/dt obtained using a 100-cm PE50 catheter (n = 6; 9400 +/- 400 mmHg/sec). The results of this study make it clear that the PE50/PE10 catheter is suitable for the measurement of left ventricular +dP/dt in the conscious rat, and that catheter design has a profound influence on both the catheter natural frequency and damping ratio.

A study of acrylic resin denture base material distortion using computer-aided holographic interferometry

A holographic interferometer for investigating deformations of dental prostheses is described. Residual stress relaxation resulting from the polymerization of acrylic resin dentures is qualitatively studied during the first 48 hours following fabrication. The resulting fringe patterns show a symmetry that is correlated to the shape of the denture. A quantitative analysis of the interferograms was performed with the aid of a computer program. The computer-aided holographic interferometer was tested using disk-shaped acrylic resin materials. Dimensional deformations resulting from temperature changes were measured with an accuracy better than 0.2 microns. Because of the aging of the resin material, the reaction to temperature changes may differ as a function of time and may be studied using quantitative comparison of deformation plots. For convenience, the original object shape can be added to or subtracted from the graphical deformation data.