Amyloid Beta Peptide (Aβ) Reverses the Cholinergic Control of Monocytic IL-1β Release.

Amyloid-β peptide (Aβ), the cleavage product of the evolutionary highly conserved amyloid precursor protein, presumably plays a pathogenic role in Alzheimer's disease. Aβ can induce the secretion of the pro-inflammatory cytokine intereukin-1β (IL-1β) in immune cells within and out of the nervous system. Known interaction partners of Aβ are α7 nicotinic acetylcholine receptors (nAChRs).

Evaluation of frozen thawed cauda epididymal sperms and in vitro fertilizing potential of bovine sperm collected from the cauda epididymal.

In the present study, the fertilizing potential of semen recovered from slaughtered bulls epididymis was evaluated after cryopreservation, by conventional techniques and flow cytometry methods. The cauda epididymal was dissected and sperm were recovered and evaluated for volume, sperm concentration, and membrane and acrosome integrity using a flow cytometer. Sperm fertility potential was tested by in vitro fertilization (IVF).

Effects of α-tocopherol and freezing rates on the quality and heterologous in vitro fertilization capacity of stallion sperm after cryopreservation.

The effects of supplementation of α-tocopherol and different freezing rates (FRs) on the ability of stallion sperm to fertilize bovine oocytes with intact zona pellucida were investigated, in an attempt to develop a model to assess cryopreserved sperm function. Semen was obtained from four purebred Lusitano stallions (n = 4). Each ejaculate was subjected to cryopreservation with a commercial extender (Ghent, Minitub Iberia, Spain), without any supplementation (control) or supplemented with 2-mM α-tocopherol.

OPTIMISATION OF TOTAL RNA EXTRACTION FROM BOVINE OOCYTES AND EMBRYOS FOR GENE EXPRESSION STUDIES AND EFFECTS OF CRYOPROTECTANTS ON TOTAL RNA EXTRACTION.

Gene expression is required for understanding bovine oocytes meiotic maturation as well as the potential of embryonic development. In the present study a standardized reagent protocol for total RNA extraction was designed for bovine oocytes and embryos, which is considered specific and less expensive. For such purpose oocytes (n = 795) recovered from about 80 ovaries were divided in three groups: Group 1 modified Trizol (MTP, n = 355); Group 2 Guanidinium thiocyanate protocol (GNTC, n = 140) and Group 3 Commercial Kit protocol (CKP, n = 60).

Effect of Conjugated Linoleic Acid on Boar Semen Quality After Long-term Refrigeration at 17°C.

In this study, the effect of conjugated linoleic acid (10 trans, 12 cis) (CLA) on refrigerated boar sperm quality parameters up to 14 days at 17°C was assessed. Semen was extended in Androhep and divided into four treatments supplemented with CLA (25, 50, 100 and 200 μm) and control group, then kept for 2 h at 22°C. Afterwards an aliquot of each treatment was removed, and mitochondrial activity, viability, lipid membrane peroxidation (LPO) and stability of the sperm plasma membrane were assessed by flow cytometry.

Reproductive Performance of Holstein Dairy Cows Grazing in Dry-summer Subtropical Climatic Conditions: Effect of Heat Stress and Heat Shock on Meiotic Competence and In vitro Fertilization.

The present study was designed to evaluate how environmental factors in a dry-summer subtropical climate in Terceira-Azores (situated in the North Atlantic Ocean: 38° 43' N 27° 12' W) can affect dairy cow (Holstein) fertility, as well as seasonal influence on in vitro oocytes maturation and embryos development. Impact of heat shock (HS) effects on in vitro oocyte's maturation and further embryo development after in vitro fertilization (IVF) was also evaluated. For such purpose the result of the first artificial insemination (AI) performed 60 to 90 days after calving of 6,300 cows were recorded for one year.

The effect of vitrification of immature bovine oocytes to the subsequent in vitro development and gene expression.

Immature bovine oocytes were vitrified using the cryotop method and their post-warming survivability and capability to undergo in vitro maturation, fertilization and subsequent embryonic development were evaluated. In addition throughout the embryonic 2-cell, 4-cell, morula and blastocyst stages, the expression of four developmentally important genes (Cx43, CDH1, DNMT1 and HSPA14) was analysed using the real-time polymerase chain reaction (PCR). Immature oocytes (n = 550) were randomly assigned to non-vitrified (fresh) or cryotop vitrification groups using ethylene glycol (EG) with 1,2 propanediol (PROH) or dimethylsulphoxide (DMSO).

Alpha-1-antitrypsin deficiency-associated panniculitis: a case report.

Panniculitis is a recognized, but rare complication of α1-antitrypsin (A1AT) deficiency. Less than 60 cases have been reported, mostly in the homozygous PiZZ variant. We report the case of a 55-year old woman with A1AT panniculitis associated with the heterozygous phenotype PiMS and discrete reduction of A1AT serum levels.

In vitro oocyte fertilization and subsequent embryonic development after cryopreservation of bovine ovarian tissue, using an effective approach for oocyte collection.

This study was undertaken to assess dissection/puncture combined technique for collecting large number of oocytes from bovine ovaries and to determine the effect of ovarian tissue cryopreservation on the oocytes capability to undergo in vitro maturation, fertilization and subsequent embryonic development. Ovaries (n=31) of slaughtered cows were cut into small fragments using a scalpel blade and the ovarian tissues were randomly assigned to cryopreserved by slow freezing and vitrification and non cryopreserved (fresh) groups. Oocytes were collected from non-atretic follicles from fresh and post-thawing ovarian tissue by the puncture method.

Effect of alpha-tocopherol on bovine in vitro fertilization.

The objectives of this work are to determine if exogenous supplementation with alpha-tocopherol increases the in vitro fertilization (IVF) rate of bovine oocytes and improves viability of selected spermatozoa after 'swim-up'. The percentage of fertilized oocytes was significantly but negatively correlated (r = -0.941, p < 0.

In vitro effect of the reproductive hormones on the oxidative burst activity of polymorphonuclear leucocytes from cows: a flow cytometric study.

In this study, the effect of reproductive hormones and substances with hormonal activity on the oxidative burst activity of blood polymorphonuclear leucocytes (PMN) high yielding dairy cows was evaluated. Different concentrations of: progesterone, oestradiol 17β, FSH, LH, GnRH, cortisol and PGF2α were incubated in vitro for 4 h with PMN of seven high milk yielding cows, during the period of anoestrous postpartum. Controls were run in parallel in which each hormone was replaced by its solvent.

Influence of apoptosis in bovine embryo's development.

The correlation between apoptosis and early bovine embryonic loss is still not fully elucidated. In the present study, the relationship between the arrest of bovine embryos at the different stages of development and apoptosis was evaluated. We used embryos 7 days after in vitro maturation and fertilization, and morphologic and biochemical apoptotic analyses were performed by using a phase contrast microscope and by the terminal transferase dUTP nick end-labelling respectively.

Effect of oestrous cycle on the oxidative burst activity of blood polymorphonuclear leucocytes in cows.

Blood polymorphonuclear leucocyte (PMN) oxidative burst activity, plasma cortisol levels, and the total and differential white blood cells counts (WBC) of six cycled dairy cows were evaluated for a period of 24 days, three times a week; on Mondays, Wednesdays and Fridays. The PMN oxidative burst was indirectly evaluated by flow cytometry, measuring the intracellular oxidation of 2',7'-dichlorofluorescein diacetate to 2',7' dichlorofluorescein (DCF) by H2O2-production. Results are presented as the mean fluorescence intensity (MFI) of DCF.

Effects of plasma urea nitrogen levels on the bovine oocyte ability to develop after in vitro fertilization.

The overall aim of the present study was to evaluate in vitro development ability of oocytes recovered from 56 Holstein Frisian heifers with low [group 1 (G1): <13 mg /dl], moderate [group 2 (G2): 13-16 mg /dl] and high [group 3 (G3): >16 mg /dl] plasma urea nitrogen (PUN) concentrations, to determine whether PUN concentrations affect the competence of oocytes to progress to blastocysts after in vitro fertilization. In vitro oocyte and embryo development was assessed by blastocyst rates, embryo total cell numbers and apoptosis. Blood samples for the determination of PUN were collected 24 h prior to collection of the ovaries at the slaughter.

Bovine oocyte quality in relation to ultrastructural characteristics of zona pellucida, polyspermic penetration and developmental competence.

In the present study, the effect of bovine oocyte quality related to ultrastructural characteristics of zona pellucida (ZP), polyspermic penetration and embryo developmental competence was evaluated. Cumulus-oocyte complexes were punctioned from 453 ovaries, classified as 1, 2, 3 and 4 according to their morphological aspect, matured for 24 h and then divided into two groups. In group A, oocytes were fixed in 2.

Assessment of sperm apoptosis in cryopreserved bull semen after swim-up treatment: a flow cytometric study.

The techniques used to prepare bovine spermatozoa for in vitro fertilization, to enhance the percentage of motile sperm cells include the swim-up (SU) method, among others. The objective of the present study was to evaluate the phosphatidylserine (PS) translocation and plasma membrane integrity as the indicator of apoptosis and necrosis in post-thaw bull sperm after SU treatment using annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI) assay. A flow cytometric method was employed to measure apoptosis levels on frozen-thawed bull spermatozoa.

Significant variability among bulls in the sperm membrane permeability for water and glycerol: possible implications for semen freezing protocols for individual males.

The aim of this study was to test the hypothesis that bulls have significant intra-individual differences in the hydraulic conductivity (L(p)) and permeability coefficient for glycerol (P(s)) of the sperm cell membrane. The permeability parameters were determined at 22, 10, and 0 degrees C of sperm from 7 Holstein Frisian artificial insemination (AI) bulls, using four ejaculates per bull. A stopped-flow approach was applied to provide temporal resolution sufficient to measure rapid cell volume changes under anisosmotic conditions in the absence or presence of glycerol.

Improvement of parameters of freezing medium and freezing protocol for bull sperm using two osmotic supports.

The aim of this study was to improve the freezing protocol of bull sperm, by investigating the influence on sperm viability after freeze/thawing of different freezing medium components, as well as the effect of cooling rates in the different stages of the cooling protocol, in single factor experiments. The experimental variables were: (1) salt-based versus a sugar-based medium (Tris versus sucrose); (2) glycerol concentration; (3) detergent (Equex) concentration; (4) presence of bicarbonate; (5) rate of cooling from 22 degrees C to holding temperature (CR1); (6) holding temperature (HT); (7) rate of cooling from holding temperature to -6 degrees C (CR2); (8) rate of cooling from -10 to -100 degrees C (CR3). All experiments were performed using five bulls per experiment (three ejaculates per bull).

Cryopreservation of boar semen: equilibrium freezing in the cryomicroscope and in straws.

Supercooling causes very abrupt temperature and osmotic changes and can thus lead to freezing damage. Supercooling can be prevented by seeding, using a sample volume and geometry that allows rapid spreading of the ice throughout the sample. In a split-sample comparison of such samples on the cooling stage of a cryomicroscope and seeded at -5 and -15 degrees C, respectively, the percentages of membrane-intact sperm and sperm with acrosomes with a 'normal apical ridge' (NAR) were 72.

Theoretical prediction of 'optimal' freezing programmes.

We have developed a quantitative description of the osmotic behaviour of cells during freezing without a presupposed value of the cooling rate. Instead, at all times the intracellular supercooling is maximised provided that it does not exceed a predetermined value 'p' (e.g.

Determination of bull sperm membrane permeability to water and cryoprotectants using a concentration-dependent self-quenching fluorophore.

The objective of this study was to determine the membrane permeability characteristics of bovine spermatozoa. These included the hydraulic conductivity (Lp), the permeability coefficients (Ps) of four common cryoprotective agents (CPAs) and the associated reflection coefficients (sigma). Stopped-flow fluorometry was applied in order to capture rapid cell volume changes under anisosmotic conditions in the absence or presence of permeant solutes (CPAs).

Penile paraffinoma.

A 40-year-old Caucasian man, originating from Ukraine, but living for the last year and a half in Portugal, presented to our department with a one year history of an irregular penile mass and phimosis. He reluctantly admitted that 8 years previously he had multiple mineral oil injections in the penis, for the purpose of penile enlargement. A diagnosis of penile paraffinoma was made and surgical excision was performed at the urology department.