To study the effect of oxygen carrying capacity on expressed changes of erythrocyte membrane protein in different storage times.

Erythrocyte membrane is crucial to maintain the stability of erythrocyte structure. The membrane protein on the surface of erythrocyte membrane enables erythrocyte to have plasticity and pass through the microcirculation without being blocked or destroyed. Decreased deformability of erythrocyte membrane protein will lead to a series of pathological and physiological changes such as tissue and organ ischemia and hypoxia. Therefore, this research collected 30 cases of healthy blood donors, and explored erythrocyte stored at different times relating indicators including effective oxygen uptake (Q), P50, 2,3-DPG, Na+-k+-ATP. Erythrocyte morphology was observed by electron microscopy. Western blot and immunofluorescence assay were used to detect membrane protein EPB41, S1P, GLTP, SPPL2A expression changes of erythrocyte. To explore the effective carry oxygen capacity of erythrocyte at different storage time resulting in the expression change of erythrocyte surface membrane protein.

[Molecular markers of Alzheimer disease early diagnostic: investigation perspectives of peripheral tissues.]

Alzheimer's disease (AD) is a progressive neurodegenerative disorder of elderly and old age people. For intravital diagnosis of the expression of signaling molecules - AD markers, cerebrospinal fluid (CSF) and peripheral tissues are used: lymphocytes and blood platelets, buccal and olfactory epithelium, skin fibroblasts. There are several changes in the production of hyper phosphorylated form of τ-protein, BACE1 and peptide Аß42 in CSF in case of AD, but CSF taking may have a number of side effects. Less traumatic taking of sampling tissues for the diagnosis of AD is in use of epithelium biopsy and blood portion. An increase in the expression of the hyper phosphorylated form of τ-protein is shown in blood lymphocytes of AD patients. An increase in the content of high molecular weight forms of phosphorylated t-protein and amyloid precursor protein-APP was also revealed in blood platelets of AD patients. Changes in the amount of 2 miRNA families - miR-132 family and miR-134 family were revealed in blood cells 1-5 years before the manifestation of clinical signs of AD. An increase in the concentration of bound calcium, synthesis of peptides Aß40 and Aß42, τ protein was observed in AD skin fibroblasts. In the olfactory and buccal epithelium an increase in the expression of hyper phosphorylated form of τ-protein and Aß peptide was detected in patients with AD. Verification of AD markers in peripheral tissues for biopsy have the important significant for life diagnostics, prevention and and target AD treatment.

Dual Signal Amplification Electrochemical Biosensor for Monitoring the Activity and Inhibition of the Alzheimer's Related Protease ß-Secretase.

The protease BACE1 (the ß-site amyloid precursor protein cleaving enzyme 1) catalyzes the first step in the synthesis of ß-amyloids (Aß), peptides that accumulate in the brain in Alzheimer's disease (AD). Measurement of BACE1 activity is important for the development of BACE1 inhibitors to slow or stop AD. To measure BACE1 cleavage of the electrode-immobilized substrate peptide, we developed a redox-generating hydroxyapatite (HAP) probe which generates electrochemical current by reaction of the nanoparticle with molybdate (MoO42-). The probe combines alkaline phosphatase (ALP) for dual signal amplification and Aß antibody to bind the probe to the immobilized peptide substrate on the surface of the electrode. We measured the activity of BACE1 at concentrations ranging from 0.25 to 100 U/mL. The use of the dual-signal HAP-ALP probe increased the signal by an order of magnitude compared to HAP-only probe, enabling detection limits as low as 0.1 U/mL. To measure the inhibition of BACE1 activity, the BACE1 inhibitor OM99-2 was added to 25 U/mL of BACE1 in concentrations ranging from 5 to 150 nM. The observed detection limit of inhibition is 10 nM of OM99-2. These results demonstrate the capabilities of this novel biosensor to measure BACE1 activity and inhibitors of BACE1 activity. To the best of our knowledge this is the first report that reaction of HAP nanoparticles with molybdate can generate electrochemical current. This dual signal amplification strategy can be extended to other electrochemical assays and adapted for wide applications.

Effects of crossbreeding on endocrine patterns determined in pregnant beef/dairy cows naturally infected with Neospora caninum.

Neospora caninum is an intracellular coccidian parasite causing abortion worldwide in dairy cattle. Studies have shown that N caninum infection modifies endocrine patterns and that beef cows or cows with a crossbreed pregnancy, especially for a greater maternal-paternal genetic distance, show a reduced risk of abortion when naturally infected compared with pure-breed Holstein Friesian (HF) pregnancies. This study examined the effects of crossbreeding on plasma progesterone (P4), pregnancy-associated glycoprotein (PAG)-1 and -2, and prolactin patterns produced during gestation in N caninum-infected beef/dairy cows. We analyzed 74 pregnancies in nonaborting cows carrying a single fetus established in 26 lactating HF cows bred with Holstein bulls (H-H), 13 HF cows bred with Limousin bulls (H-L), 12 HF cows used as recipients of transferred in vivo-produced frozen-thawed Rubia Gallega (beef breed; RG) embryos (H-RG-ET), and 23 RG suckling cows bred with RG bulls (RG-RG). Of the cows, 29 (39%) were seropositive for N caninum. Blood samples for hormone and placental protein determinations were collected on Days 30, 60, 90, 120, 150, and 180 of gestation. Procedures of repeated measures analysis of variance throughout gestation revealed higher PAG-1 levels in the H-L and H-RG-ET groups compared with H-H and RG-RG. Higher prolactin levels were detected in RG-RG than in the remaining groups. N caninum seropositivity and fetal genotype had a significant effect on PAG-2 concentrations, such that highest levels of PAG-2 occurred in RG-RG seropositive cows and lowest in H-H seropositive cows, whereas Neospora-seropositive cows showed lower P4 concentrations than their seronegative partners. In conclusion, chronic N caninum infection modifies endocrine patterns of PAG-2 and P4 during pregnancy, whereas PAG-1 and prolactin concentrations are affected by breed and fetal genotype, irrespective of Neospora infection status.

Relationship of progesterone, bovine pregnancy-associated glycoprotein-1 and nitric oxide with late embryonic and early fetal mortalities in dairy cows.

The aim of the present study was to determine the relationship of progesterone (P4), bovine pregnancy-associated glycoprotein-1 (bPAG-1) and nitric oxide (NO) levels with late embryonic (LEM; day 28 to day 42) and early fetal mortalities (EFM; > day 42 to day 56) in dairy cows. Transrectal ultrasonography (6-8 MHz) was performed in 100 Holstein-Friesian cows at days 28, 42 and 56 after artificial insemination (AI; day 0) to diagnose pregnancy and to monitor the fate of the embryo. After ultrasound scanning of each cow, a milk sample was collected for assessment of P4 by an ELISA test and a blood sample was collected for assessment of bPAG-1, by using a double-antibody radioimmunoassay, and serum NO metabolites (nitrate + nitrite). Based on ultrasonographic examinations and bPAG-1-RIA, 41 of 100 inseminated cows were confirmed pregnant at day 28 after AI. Nine cows suffered of LEM, and 6 cows suffered of EFM and the overall pregnancy loss rate was 36.6% (15/41) between days 28 and 56 of pregnancy. By logistic regression analysis, there were no significant relationships between the level of P4 and bPAG-1 at day 28 after AI and the occurrence of LEM and EFM. Also, there were no significant relationships between the levels of P4 and bPAG-1 at day 42 and the occurrence of EFM. On the other hand, a significant relationship (P<0.05) was found between NO level at day 28 and the occurrence of LEM. In conclusion, measurement of the serum NO concentration at day 28 of pregnancy might help to predict the outcome of pregnancy by day 42 in dairy cows but further studies are needed to confirm this.

Detection of Candida albicans Sap2 in cancer patient serum samples by an indirect competitive enzyme-linked immunosorbent assay for the diagnosis of candidiasis.

BACKGROUND: The secreted aspartyl proteinases 2 (Sap2) of Candida albicans (C. albicans) is a potential marker of candididasis. It is a virulence factor associated with adherence and tissue invasion. AIM: In order to detect Sap2 in clinical sera, we developed an indirect competitive enzyme-linked immunosorbent assay (ELISA). MATERIALS AND METHODS: Polyclonal antibodies were produced for Sap2 by injecting Sap2 into a New Zealand White inbred rabbit. They could be used at a dilution exceeding 1:1200 in an indirect ELISA, and detected Sap2 concentration up to 1 ng/mL. RESULTS: Of the 286 cancer serum samples tested, 16.8% were found as candidiasis. The test was simple and economical to perform and had a level of sensitivity for detection of low-titer positive sera; thus, it may be proven to be of value in epidemiological studies on candidiasis.

Relationship between plasma progesterone and pregnancy-associated glycoprotein concentrations during early pregnancy in dairy cows.

The relationship between the concentration of plasma progesterone (P4) during embryo attachment or at recognition of pregnancy, and that of pregnancy-associated glycoprotein (PAG) was assessed in dairy cows. The outcome of artificial insemination (AI) was classified as positive (AI+), negative (AI-), or late embryonic mortality (EM) by measuring circulating PAG concentrations and by ultrasonography. Based on P4 concentrations at either day 21 or day 15, AI+ and EM cows were classified into 'low' (P4 concentrationsmean) P4 groups. In both experiments, the threshold of P4 concentration between the 'low' and 'high' groups was approximately 6ng/mL. PAG concentrations were lower in the 'low' group only when P4 concentrations were below the threshold. The study findings suggest that a possible P4 threshold exists below which PAG secretion may be impaired.

Effect of small hairpin RNA targeting endothelin-converting enzyme-1 in monocrotaline-induced pulmonary hypertensive rats.

The purpose of this study was to investigate the therapeutic effects of small hairpin RNA (shRNA) targeting endothelin-converting enzyme (ECE)-1 in monocrotaline (MCT)-induced pulmonary hypertensive rats. Ninty-four Sprague-Dawley rats were divided into three groups: control (n = 24), MCT (n = 35) and shRNA (n = 35). Four-week survival rate in the shRNA group was significantly increased compared to that in the MCT group. The shRNA group showed a significant improvement of right ventricular (RV) pressure compared with the MCT group. The MCT and shRNA groups also showed an increase in RV/(left ventricle + septum) ratio and lung/body weight. Plasma endothelin (ET)-1 concentrations in the shRNA group were lower than those in the MCT group. Medial wall thickness of pulmonary arterioles were increased after MCT injection and was significantly decreased in the shRNA group. The number of intra-acinar muscular pulmonary arteries was decreased in the shRNA group. The mRNA expressions of ET-1 and ET receptor A (ET(A)) were significantly decreased in the shRNA group in week 4. The protein levels of ET(A) were decreased in the shRNA group in week 2. The protein levels of tumor necrosis factor-α and vascular endothelial growth factor were decreased in the shRNA group in week 4. In conclusion, the gene silencing with lentiviral vector targeting ECE-1 could be effective against hemodynamic, histopathological and gene expression changes in pulmonary hypertension.

The elevation of serum napsin A in idiopathic pulmonary fibrosis, compared with KL-6, surfactant protein-A and surfactant protein-D.

BACKGROUND: Napsin A, an aspartic protease, is mainly expressed in alveolar type-II cells and renal proximal tubules and is a putative immunohistochemical marker for pulmonary adenocarcinomas. This study sought to determine whether napsin A could be measured in the serum to evaluate its relationship to idiopathic pulmonary fibrosis (IPF) and determine whether renal dysfunction might affect serum napsin A levels. METHODS: Serum levels of napsin A were measured in 20 patients with IPF, 34 patients with lung primary adenocarcinoma, 12 patients with kidney diseases, and 20 healthy volunteers. Surfactant protein (SP)-A, SP-D, and Krebs von den Lungen-6 (KL-6) levels in serum and pulmonary function tests were also evaluated in IPF patients. RESULTS: Circulating levels of napsin A were increased in patients with IPF, as compared with healthy controls, and they correlated with the severity of disease. Moreover, the serum napsin A levels were not elevated in patients with pulmonary adenocarcinoma or renal dysfunction. The distinguishing point between IPF and the controls was that the area under the receiver operating characteristic curve (ROC) of napsin A was larger than that of KL-6, SP-A, or SP-D. CONCLUSION: These findings suggest that serum napsin A may be a candidate biomarker for IPF.

Characterisation of pregnancy losses after embryo transfer by measuring plasma progesterone and bovine pregnancy-associated glycoprotein-1 concentrations.

The aim of this analysis was to determine whether pregnancy loss (PL) after embryo transfer (ET) in cattle was related to maternal progesterone (P4) concentrations during and shortly after ET, and maternal bovine pregnancy-associated glycoprotein-1 (bPAG-1) concentrations in plasma at days 25-35 of gestation. Embryos (n=260) were produced either in vivo after superovulation (n=115), or in vitro from oocytes (obtained with ovum pick-up) in co-culture (n=44) or cultured in a synthetic medium (n=101). Overall, PL was 56.9% (148) and no significant differences occurred in calving rate among the three embryo production groups. There was no difference in P4 concentrations on days 7-14 of gestation in the three groups, nor between ongoing and interrupted pregnancies. Between days 25 and 35 of pregnancy, bPAG-1 concentrations were unaffected by embryo production, but in cattle that had PL between days 26 and 120, four bPAG-1 profiles could be detected. Between days 25 and 32, bPAG-1 concentrations were influenced by PL, and concentrations were significantly lower in animals in which PL occurred between days 26 and 120 than in those animals that aborted later or calved at term. Early P4 concentrations suggested that maternal luteal factors were not responsible for PL which appeared to be caused by impaired conceptus development (regardless of embryo type) as reflected by low maternal bPAG-1 concentrations prior to embryonic death.

Changes in serum pregnancy-associated glycoprotein, pregnancy-specific protein B, and progesterone concentrations before and after induction of pregnancy loss in lactating dairy cows.

Lactating crossbred dairy cows were synchronized to receive a timed artificial insemination (TAI), and blood samples were collected from all cows from TAI until pregnancy diagnosis 39 d after TAI (period 1), and from pregnant cows from onset of treatment until the end of the experiment (period 2). Cows diagnosed pregnant 39 d after TAI were randomly assigned to 1 of 3 treatments to receive (1) an i.m. injection of saline (CON, n=10); (2) an i.m. injection of PGF(2α) (PGF, n=10); or (3) an intrauterine infusion of 120 mL of hypertonic saline (INF, n=9). During period 1, serum pregnancy-associated glycoprotein (PAG) concentrations began to increase in pregnant cows by 25 d after TAI and differed from those in nonpregnant cows by 27 d after TAI, whereas serum pregnancy-specific protein B (PSPB) concentrations in pregnant cows differed from those in nonpregnant cows by 22 d after TAI. During period 2, time from treatment to cessation of the embryonic heartbeat was greater for PGF than for INF cows (36.0±5.7 vs. 0.2±0.1 h, respectively), and time from treatment to conceptus disappearance was greater for INF than for PGF cows (7.1±3.3 vs. 1.9±0.3 d, respectively). Overall, progesterone concentration was greater for CON and INF than for PGF cows (8.7±2.8, 8.2±3.1, and 1.0±2.3 ng/mL, respectively) due to luteal regression for PGF cows and corpus luteum maintenance for CON and INF cows. Serum PAG and PSPB concentrations differed among CON cows and PGF and INF cows beginning 1 and 2.5 d after treatment for PAG and PSPB, respectively. By 9.5 d after treatment, PAG and PSPB concentrations were similar to those of nonpregnant cows. We conclude that although timing of conceptus expulsion occurred 5.2 d later for INF than for PGF cows, serum PAG and PSPB concentrations decreased at a similar rate from the onset of treatment for both models of pregnancy loss evaluated.

Effect of restraint stress on plasma concentrations of cortisol, progesterone and pregnancy associated-glycoprotein-1 in pregnant heifers during late embryonic development.

The aim of the present study was to evaluate the effect of restraint stress, which is commonly practised in the field, on plasma concentrations of cortisol, progesterone (P4) and bovine pregnancy-associated glycoprotein-1 (boPAG-1) in pregnant heifers between Days 30 to 40 of gestation. Twelve Holstein-Friesian heifers between Days 30 (Day 0 of experiment) and 40 (Day 10 of experiment) of pregnancy in a Hungarian dairy farm were used in the present study. The heifers were exposed to an acute stressor consisting of immobilisation (restraint stress) in a crush for 2 h (Group 1, n = 6) on Day 2 (Hour 48) and for 2 × 2 h (Group 2, n = 6) on Days 2 and 3 (Hour 72) of the experiment. Transrectal ultrasonography (7.5 MHz linear-array rectal transducer) was performed daily from Day 0 to Day 10 of the experiment to detect embryonic heartbeat or the fate of the conceptus. Blood samples were withdrawn before each ultrasonographic examination. Additional blood samples were withdrawn by 1 and 2 h (at Hours 49 and 50 in Groups 1 and 2 and Hours 73 and 74 in Group 2) of the onset of applying the stressor. Plasma cortisol, P4 and boPAG-1 concentrations were measured by radioimmunoassay. Acute restraint stress significantly (P < 0.001) increased the plasma cortisol level in pregnant heifers at 1 h of the exposure to the stressor at Days 2 (48 h) and 3 (72 h) of the experiment. On the other hand, the restraint stress did not affect the concentration of P4 and boPAG-1 concentrations in both groups. In conclusion, restraint stress for 2 h during early pregnancy in heifers increased blood cortisol, but it did not affect the concentrations of P4 and boPAG-1 between Days 30 to 40 of gestation.

Clinical implications of induced twin reduction in dairy cattle.

Embryo reduction may prevent the negative effects of twinning in dairy cattle; however, the technique may carry an additional risk of pregnancy loss. The aim of this study was to evaluate the effect on pregnancy maintenance of embryo reduction by manual amnion rupture in unilateral and bilateral twin pregnant cows. A secondary objective was to examine the dynamics of endocrine factors following the treatment. On Day 35-41 of gestation 55 cows bearing two live twin embryos (28 bilateral, 27 unilateral) were randomly assigned to a twin reduction group (n = 27; cows fitted with a progesterone releasing intra-vaginal device for 21 days after manual amnion rupture) or control group (n = 28; untreated cows). Pregnancy loss before Day 90 was recorded in nine control and eleven twin reduction cows (32.1% vs 40.7%, respectively, p = 0.508). Logistic regression models indicated that laterality was the only variable significantly affecting pregnancy loss. The pregnancy loss risk was 8.7 times higher for unilateral than for bilateral twin pregnancies (59.3% vs 14.3%, respectively, P < 0.001) yet was similar in the unilateral control and unilateral twin reduction cows (62.3% vs 53.8%, respectively, P = 0.581). In contrast, four of 14 cows with bilateral twin pregnancies undergoing twin reduction lost their pregnancies while no losses were recorded in control cows with bilateral pregnancies (P = 0.049). A rise in plasma progesterone concentration was detected on the day following treatment in the twin reduction group and concentrations remained high within the first week of treatment. Plasma pregnancy-associated glycoprotein-1 (PAG-1) concentrations fell between Day 35-41 and Day 42-48, regardless of treatment. Our findings indicate that embryo reduction by manual amnion rupture did not carry an additional risk of pregnancy loss for unilateral twin pregnancies, whereas it increased the risk of pregnancy failure in bilateral twin pregnancies. However, benefits of preventing cows from delivering twins might also be considered when assessing the success of embryo reduction in bilateral twin pregnancies.

Effects of embryo size at transfer (whole versus demi) and early pregnancy progesterone supplementation on embryo growth and pregnancy-specific protein bovine concentrations in recipient dairy heifers.

The objectives of this study were to evaluate embryonic size and survival, plasma progesterone (P4) and pregnancy-specific protein bovine (PSPB) concentrations in early pregnancies (n = 99) following the transfer of one whole (n = 66) or one demi (n = 33) embryo to recipient virgin dairy heifers. The experiment was designed to evaluate the fixed effects of embryo size at transfer (whole or demi embryo) on Day 7 of the estrous cycle (Day 0 = estrus) and P4 supplementation between Days 7 to 19 through an intravaginal device (yes or no) on plasma P4 and PSPB concentrations and on embryo measurements. Plasma P4 concentrations were measured by RIA on Days 0, 7, 14, 19, 21, 25, 35, 42, 49, 56 and 63 of pregnancy and, PSPB concentrations were measured by ELISA on Days 7, 21, 25, 35, 42, 49, 56 and 63. The presence of an embryonic vesicle was detected on Day 25, embryonic/fetal movements and heartbeat were evaluated on Days 42 and 63 and embryo measurements [crown-rump length (CRL) and width at mid body] were obtained on Day 42 through ultrasonography. In non-supplemented pregnancies, Day 42 whole embryos had higher (P < 0.05) CRL and width than demi embryos, but the difference averaged only 1 to 2 mm. In P4 supplemented pregnancies, whole and demi embryos attained a similar size on Day 42 of pregnancy. Embryo size at transfer, early exogenous P4 supplementation and their interactions had no effects (P > 0.05) on plasma P4 concentrations. However, the post-hoc LSD evaluation showed that plasma P4 concentrations on Day 25 were higher (P < 0.001) in whole than in demi embryo derived pregnancies and, that exogenous P4 supplementation increased (P < 0.05) plasma P4 concentrations on Day 19 of pregnancy. The plasma PSPB detection rate on Days 7 to 63 of pregnancy was similar in pregnancies resulting from the transfer of whole and demi embryos. From a total of 93 recipients remaining pregnant until Day 63, plasma PSPB was constantly undetectable on Day 7, was detected in 4% of Day 21 samples, 41% of Day 25, 95% of Day 35, 96% of Day 42, 99% of Day 49 and in 100% of samples of Days 56 and 63. Concentrations of PSPB increased (P < 0.05) from Days 21 to 42 and from Days 56 to 63, with a plateau between Days 42 to 56. Demi embryo pregnancies had higher (P < 0.05) plasma PSPB concentrations on Days 35 and 42 than whole embryo pregnancies. Progesterone supplementation had a positive effect (P < 0.01) on PSPB concentrations from Days 35 to 63. Concentrations of PSPB were similar in non-supplemented whole and demi embryo pregnancies from Days 7 to Day 63. In contrast, in supplemented recipients, demi embryo pregnancies had higher (P < 0.05) PSPB concentrations on Days 25 to 42 than whole embryo pregnancies. No significant correlation was found between P4 and PSPB concentrations or between the concentrations of these hormones and embryonic measurements on Day 42. In conclusion, demi embryos experienced a compensatory growth until Day 42 of pregnancy, attaining a similar size to that of whole embryos and originating conceptuses producing similar plasma PSPB concentrations to those of whole embryo derived conceptuses. Embryonic growth and conceptus secretion of PSPB were positively stimulated by early pregnancy exogenous P4 treatment.

Comparison of accuracy of ultrasonography, progesterone, and pregnancy-associated glycoprotein tests for pregnancy diagnosis in semidomesticated reindeer.

The aim of the study was to compare transrectal ultrasound with progesterone (P4) and pregnancy-associated glycoproteins (PAGs) as pregnancy detection methods for semidomesticated reindeer (Rangifer tarandus tarandus) in field conditions. Female reindeer (n=195) were scanned transrectally by a 7.5-MHz linear array transducer, and blood was sampled either in December 2005 (n=33), December 2006 (n=92), or January 2007 (n=70) during early or mid gestation. Plasma levels of P4 and PAGs were assessed by radioimmunoassay (RIA). Based on calving records, the sensitivity, specificity, predictive values, and the overall accuracy of the three tests were calculated. The overall calving rate calculated from the calving records was 86.2%. The overall accuracy of transrectal ultrasound was 99.5%. The sensitivity and specificity of transrectal ultrasound were 99.4% and 100%, respectively. In the plasma P4 test, the threshold level of 5.0 nmol/L gave the highest overall accuracy (94.9%). The sensitivity of the P4 test decreased from 96.4% to 81.5%, when the threshold level increased from 5.0 nmol/L to 8.0 nmol/L, while the specificity remained at 85.2% over the range of these cutoff values. The overall accuracy of the plasma PAG test decreased from 96.4% to 64.1% when the plasma PAG threshold level increased from 0.5 ng/mL to 3.5 ng/mL, whereas sensitivity decreased from 99.4% to 58.3%. Specificity increased from 77.8% to 100% when the plasma PAG threshold level reached 3.0 ng/mL. Transrectal ultrasound showed higher diagnostic values than those of plasma P4-RIA and PAG-RIA in diagnosing pregnancy of reindeer, with the advantage that diagnoses can be made in real time in field conditions.

Dietary protein during gestation affects circulating indicators of placental function and fetal development in heifers.

The influences of nutritional protein during the first and second trimesters of pregnancy on placental hormones and fetal growth were determined in composite beef heifers. At artificial insemination, heifers were stratified by weight within each composite genotype into 4 treatment groups: High High (HH=1.4kg crude protein (CP)/day for first and second trimesters of gestation; n=16), High Low (HL=1.4kg CP/day for first trimester and 0.4kg CP/day for second trimester; n=19), Low High (LH=0.4kg CP/day for first trimester and 1.4kg CP/day for second trimester; n=17) or Low Low (LL=0.4kg CP/day for first and second trimesters; n=19). Maternal plasma bovine pregnancy associated glycoprotein (bPAG) and progesterone (P4) were determined at gestation day (gd) 28, 82, 179 and 271 (mean gestation length 286 days) in addition to P4 at term. Estrone sulphate (ES) and bovine placental lactogen (bPL) concentrations were measured at gd 124, 179, 236 and 271 and at term in addition to ES at gd 82. Low dietary protein increased placental function as indicated by increased bPAG (P<0.001) and ES (P=0.02) concentrations in first trimester and increased bPL concentrations (P=0.01) in the second trimester of gestation. In the third trimester, when dietary treatment had ceased, placental function was no longer associated with previous dietary treatments. Dam genotype affected placental function as measured by bPL (P<0.001) and ES concentrations (P=0.02). Calf gender, heifer age and maternal insulin-like growth factor (IGF)-I, -II and leptin did not affect hormonal indicators or circulating markers of placental function. Enhanced placental function during the third trimester, as measured by ES, was associated with increased calf birth weight (P=0.003).

Factors affecting plasma pregnancy-associated glycoprotein 1 concentrations throughout gestation in high-producing dairy cows.

This study was designed to establish the factors, if any, which could affect plasma pregnancy-associated glycoprotein-1 (PAG-1) expression in a study population of 87 pregnant, high-producing dairy cows. The factors examined were: semen providing breed (Holstein-Friesian vs Limousin), outcome of gestation (male vs female newborn, and singleton vs twin pregnancies), lactation number, milk production at pregnancy diagnosis, plasma progesterone concentration, season of gestation (warm period, March-November vs cool period, December-February), and day of gestation (40, 90, 120, 150, 180 and 210). Pregnancy was diagnosed by transrectal ultrasound on day 40 post-insemination and by palpation per rectum on days 90, 120, 150, 180 and 210. Blood samples were collected from each animal immediately before each pregnancy diagnosis. The relative contributions of the different factors on PAG-1 concentrations were evaluated by GLM repeated measures analysis of variance. No significant effects of the herd, foetal sex, milk production, lactation number and plasma progesterone concentrations were observed. In contrast, twin pregnancy, the use of Limousin semen and conception during the cool period were correlated with significantly increased plasma PAG-1 concentrations throughout gestation. Our data indicate that both cow well-being during early placental development, determined in our conditions by reduced heat stress when conception occurred in the cool season, and crossbreed pregnancies lead to improved PAG-1 production throughout the gestation period.

Factors affecting plasma prolactin concentrations throughout gestation in high producing dairy cows.

The aim of the present study was to investigate possible relationships between plasma concentrations of prolactin and the following factors throughout gestation in lactating dairy cows: photoperiod, season, milk production, Neospora caninum-seropositivity, twin pregnancy, and plasma concentrations of pregnancy associated glycoproteins-1 (PAG-1), progesterone and cortisol. Pregnancy was diagnosed by trans-rectal ultrasonography on Day 40 post-insemination and by palpation per rectum on Days 90, 120, 150, 180 and 210 or until abortion in aborting cows. Blood samples were collected from each animal immediately before each pregnancy diagnosis. The study population was comprised of 73 non-aborting (54 Neospora-seropositive cows) and 20 aborting cows (all Neospora-seropositive) cows. In non-aborting cows, GLM repeated measures of analysis of variance revealed that lactation number and days in milk had no effect on plasma prolactin concentrations throughout gestation, whereas high plasma prolactin concentrations were significantly associated with high plasma levels of cortisol and PAG-1, with Neospora-seropositivity, positive photoperiod (increasing day length), twin pregnancy, and with low plasma progesterone concentrations. An interaction among plasma prolactin, plasma cortisol and milk production was observed in that plasma prolactin concentrations differed significantly throughout gestation and were highest in high-producing cows with high cortisol levels. In Neospora-seropositive non-aborting versus aborting cows, mean prolactin concentrations failed to differ on Days 40, 90, 120, 150 and 180 of pregnancy, whereas prolactin values were significantly lower (P=0.03) in aborting animals on Day 210 of pregnancy. Our results indicate that a positive photoperiod and Neospora-infection lead to increased plasma prolactin concentrations throughout gestation. Reduced prolactin concentrations detected in Neospora-seropositive aborting cows compared to non-aborting animals suggests a protective effect of prolactin in N. caninum infection.

Factors affecting plasma progesterone in the early fetal period in high producing dairy cows.

The aim of the present study was to determine whether certain animal- or management related factors could affect plasma progesterone concentrations on Day 42 of gestation in high producing dairy cows. Factors affecting early fetal loss were also analyzed. The study population was comprised of 199 pregnant cows classified as having high (> or =9 ng/ml) or low (<9 ng/ml) plasma progesterone concentrations. Through logistic regression procedures it was determined that, based on the odds ratio, cows with two or more corpora lutea were three times more likely to have high progesterone concentrations than cows with a single corpus luteum. Low producing cows during the warm season were 2.86 times more likely to have high progesterone concentrations than the remaining cows. Primiparous cows with high concentrations (>4 ng/ml) of pregnancy associated glycoprotein-1 (PAG-1) were 2.73 times more likely to have high progesterone concentrations than the remaining cows. Of the 199 pregnancies, 25 (12.6%) suffered early fetal loss: 22/136 (16.2%) during the warm season and 3/63 (4.8%) during the cool season, all in cows without additional corpora lutea. Based upon the odds ratio, cows without an additional corpus luteum were 3.67 times more likely to suffer fetal loss during the warm season than during the cool season. Our results indicate that milk production, the presence of two or more corpora lutea and plasma PAG-1 concentrations can affect plasma progesterone concentrations at the onset of the fetal period. The presence of an additional corpus luteum strongly diminished the risk of early fetal loss during the warm period.

[Steroid-binding protein levels in breast cancer patients].

Blood levels of sex hormone-binding globulin (SHBG), transcortin and pregnancy-related alpha2-glycoprotein (PalphaGP) were assayed using commercial kits for alpha-protein analysis in 223 breast cancer patients and 180 healthy women. Elevated concentration of SHBG was characteristic of both the luteal stage of menstrual cycle and menopause. It occurred chiefly in patients under 59 whereas at older age no differences from control were observed. Blood- transcortin in tumor patients was significantly lower than in control; conversely, PalphaGP concentration was higher irrespective of age. Since steroid-binding protein levels in the blood of breast cancer patients appeared to differ from those in healthy women, relevant data should be considered when hormone-metabolic status of reproductive and menopausal patients is identified.