Effects of oral calcium supplementation on productive and reproductive performance in Holstein cows

The objectives of this experiment were to determine the effects of oral Ca supplementation on milk yield, body condition, pregnancy per artificial insemination (P/AI), and days to pregnancy in Holstein cows considered to be of low (LRM; no calving assistance, live singleton without retained placenta) or high (HRM; at least one of the following: dystocia, twins, stillbirth, retained placenta, or vulvo-vaginal laceration) risk of developing metritis. The hypotheses were that oral Ca supplementation during the early postpartum period would reduce the loss of body condition and improve lactation performance and reproduction. Four hundred fifty Holstein cows were blocked by parity as primiparous cows (n=174) or multiparous cows (n=276). Within parity, a cow considered at HRM was matched with a cow of LRM and the pair was randomly assigned to control (no Ca supplementation), 86g of Ca on d 0 and 1 postpartum (CaS1), or 86g of Ca on d 0 and 1 postpartum followed by 43g/d on d 2 to 4 postpartum (CaS4). Body condition was scored at calving and 32 d postpartum and estrous cyclicity was evaluated at 38 and 52 d postpartum. Milk yield was recorded daily. Multiparous cows were classified as above or below the mean 305-d mature equivalent milk yield based on production in the previous lactation. Reproductive performance was evaluated for the first 210 d postpartum. Body condition did not differ among treatments, and cows lost on average 0.44 units of body condition in the first month of lactation. Calcium supplementation did not affect milk yield in the first 5 mo postpartum. For multiparous cows, Ca supplementation was beneficial to milk yield in the first 30 DIM in cows of greater production potential, but detrimental to multiparous cows with below average production potential. Calcium supplementation to primiparous cows reduced P/AI at first (control=55.8, CaS1=31.5, CaS4=37.0%) and all artificial inseminations (control=48.5, CaS1=34.6, CaS4=38.5%); however, Ca supplementation to multiparous cows improved P/AI at the first (control=32.1, CaS1=38.6, CaS4=41.3%) and all artificial inseminations (control=28.1, CaS1=35.3, CaS4=40.5%). These responses in P/AI to Ca supplementation resulted in extended median days to pregnancy (control=75, CaS1=100, CaS4=94 d) and smaller proportion of pregnant cows (control=89.3, CaS1=83.9, CaS4=83.9%) in primiparous cows, but shorter days to pregnancy (control=115, CaS1=94, CaS4=94 d) and increased proportion of pregnant cows in multiparous cows (control=67.0, CaS1=77.2, CaS4=74.3%). Risk of metritis depressed most measures of reproduction evaluated in the experiment. Results indicate that responses to oral Ca supplementation are conditional on parity and production potential of cows. Oral Ca supplementation was detrimental to reproduction in primiparous cows. On the other hand, Ca supplementation benefited reproduction in multiparous cows and milk yield in the cohort of multiparous cows of greater production potential.

Blood circulating microparticle species in relapsing-remitting and secondary progressive multiple sclerosis. A case-control, cross sectional study with conventional MRI and advanced iron content imaging outcomes

BACKGROUND

Although multiple sclerosis (MS) is thought to represent an excessive and inappropriate immune response to several central nervous system (CNS) autoantigens, increasing evidence also suggests that MS may also be a neurovascular inflammatory disease, characterized by endothelial activation and shedding of cell membrane microdomains known as 'microparticles' into the circulation.

OBJECTIVE

To investigate the relationships between these endothelial biomarkers and MS.

METHODS

We examined the relative abundance of CD31(+)/PECAM-1, CD51(+)CD61(+) (αV-β3) and CD54(+) (ICAM-1) bearing microparticles in sera of healthy individuals, patients with relapsing-remitting MS, and secondary-progressive MS. We also investigated the correlation among circulating levels of different microparticle species in MS with conventional MRI (T2- and T1-lesion volumes and brain atrophy), as well as novel MR modalities [assessment of iron content on susceptibility-weighted imaging (SWI)-filtered phase].

RESULTS

Differences in circulating microparticle levels were found among MS groups, and several microparticle species (CD31(+)/CD51(+)/CD61(+)/CD54(+)) were found to correlate with conventional MRI and SWI features of MS.

CONCLUSION

These results indicate that circulating microparticles' profiles in MS may support mechanistic roles for microvascular stress and injury which is an underlying contributor not only to MS initiation and progression, but also to pro-inflammatory responses.

Diffusion and perfusion MRI to differentiate treatment-related changes including pseudoprogression from recurrent tumors in high-grade gliomas with histopathologic evidence

BACKGROUND AND PURPOSE

Treatment-related changes and recurrent tumors often have overlapping features on conventional MR imaging. The purpose of this study was to assess the utility of DWI and DSC perfusion imaging alone and in combination to differentiate treatment-related effects and recurrent high-grade gliomas.

MATERIALS AND METHODS

We retrospectively identified 68 consecutive patients with high-grade gliomas treated by surgical resection followed by radiation therapy and temozolomide, who then developed increasing enhancing mass lesions indeterminate for treatment-related changes versus recurrent tumor. All lesions were diagnosed by histopathology at repeat surgical resection. ROI analysis was performed of the enhancing lesion on the ADC and DSC maps. Measurements made by a 2D ROI of the enhancing lesion on a single slice were recorded as ADCLesion and rCBVLesion, and measurements made by the most abnormal small fixed diameter ROI as ADCROI and rCBVROI. Statistical analysis was performed with Wilcoxon rank sum tests with P = .05.

RESULTS

Ten of the 68 patients (14.7%) had treatment-related changes, while 58 patients (85.3%) had recurrent tumor only (n = 19) or recurrent tumor mixed with treatment effect (n = 39). DWI analysis showed higher ADCLesion in treatment-related changes than in recurrent tumor (P = .003). DSC analysis revealed lower relative cerebral blood volume (rCBV)Lesion and rCBVROI in treatment-related changes (P = .003 and P = .011, respectively). Subanalysis of patients with suspected pseudoprogression also revealed higher ADCLesion (P = .001) and lower rCBVLesion (P = .028) and rCBVROI (P = .032) in treatment-related changes. Applying a combined ADCLesion and rCBVLesion model did not outperform either the ADC or rCBV metric alone.

CONCLUSIONS

Treatment-related changes showed higher diffusion and lower perfusion than recurrent tumor. Similar correlations were found for patients with suspected pseudoprogression.

Correlation of the dynamics of native human acetylcholinesterase and its inhibited huperzine A counterpart from sub-picoseconds to nanoseconds

It is a long debated question whether catalytic activities of enzymes, which lie on the millisecond timescale, are possibly already reflected in variations in atomic thermal fluctuations on the pico- to nanosecond timescale. To shed light on this puzzle, the enzyme human acetylcholinesterase in its wild-type form and complexed with the inhibitor huperzine A were investigated by various neutron scattering techniques and molecular dynamics simulations. Previous results on elastic neutron scattering at various timescales and simulations suggest that dynamical processes are not affected on average by the presence of the ligand within the considered time ranges between 10 ps and 1 ns. In the work presented here, the focus was laid on quasi-elastic (QENS) and inelastic neutron scattering (INS). These techniques give access to different kinds of individual diffusive motions and to the density of states of collective motions at the sub-picoseconds timescale. Hence, they permit going beyond the first approach of looking at mean square displacements. For both samples, the autocorrelation function was well described by a stretched-exponential function indicating a linkage between the timescales of fast and slow functional relaxation dynamics. The findings of the QENS and INS investigation are discussed in relation to the results of our earlier elastic incoherent neutron scattering and molecular dynamics simulations.

Pressure-induced molten globule state of human acetylcholinesterase: structural and dynamical changes monitored by neutron scattering

We used neutron scattering to study the effects of high hydrostatic pressure on the structure and dynamics of human acetylcholinesterase (hAChE).

Effect of progesterone supplementation on fertility responses of lactating dairy cows with corpus luteum at the initiation of the Ovsynch protocol

The objectives of this study were to determine the effects of supplemental progesterone on fertility responses of lactating dairy cows with a CL at the initiation of the timed artificial insemination (AI) program. Holstein cows were subjected to the Ovsynch protocol (Day -10 GnRH, Day -3 PGF2α, Day -0.7 GnRH, and Day 0 timed AI). Ovaries were scanned by ultrasonography on Day -10 and cows with CL were blocked by pen and assigned randomly to receive no supplemental progesterone (control, n = 863) or to receive a controlled internal drug-release (CIDR) insert containing progesterone from Days -10 to -3 (1CIDR, n = 862). Cows were observed for signs of estrus beginning on Day -9 based on removal of tail chalk and those in estrus received AI on the same day. Blood sampled from a subset of cows was analyzed for progesterone concentrations on Days -10, -9, -7, -5, -3, 0, 6, 13, and 19. Pregnancy was diagnosed on Days 32 and 60 after AI. Supplementation increased (P < 0.01) progesterone concentrations between Day -9 and -3 compared with control (7.5 vs. 6.2 ng/mL). Treatment had no effect on the ovulatory response to the first and final GnRH injections of the Ovsynch protocol, the proportion of cows that maintained their CL until the day of PGF2α injection, or the diameter of the ovulatory follicle before AI. Although the overall proportion of cows in estrus at AI did not differ between treatments, progesterone supplementation prevented (P < 0.01) cows from coming into estrus from Days -9 to -3 (0.0% vs. 4.7%), whereas it increased (P = 0.02) the proportion of cows inseminated in estrus from Days -2 to -1 (7.1% vs. 4.5%). Pregnancy per AI (P/AI) tended to be reduced (P = 0.06) by supplemental progesterone on Day 32 (40.5% vs. 45.0%), but not on Day 60 after AI (36.6% vs. 39.7%). A tendency for an interaction (P = 0.09) between treatment and the presence of CL at the PGF2α injection was observed for P/AI on Day 32 in cows that received timed AI because progesterone supplementation reduced P/AI in cows that maintained their CL until Day -3 (40.3% vs. 46.7%); however, it increased P/AI in those that did not have a CL at PGF2α (38.1% vs. 27.7%). Treatment did not affect pregnancy loss between Days 32 and 60 of gestation. In conclusion, incorporating a single intravaginal insert to the timed AI program increased progesterone concentrations in plasma by 1.3 ng/mL, but did not benefit fertility in dairy cows that have CL at the initiation of the synchronization protocol.

Peroxisome proliferator-activated receptor ligands regulate lipid content, metabolism, and composition in fetal lungs of diabetic rats

Maternal diabetes impairs fetal lung development. Peroxisome proliferator-activated receptors (PPARs) are ligand-activated transcription factors relevant in lipid homeostasis and lung development. This study aims to evaluate the effect of in vivo activation of PPARs on lipid homeostasis in fetal lungs of diabetic rats. To this end, we studied lipid concentrations, expression of lipid metabolizing enzymes and fatty acid composition in fetal lungs of control and diabetic rats i) after injections of the fetuses with Leukotriene B4 (LTB4, PPARα ligand) or 15deoxyΔ(12,14)prostaglandin J2 (15dPGJ2, PPARγ ligand) and ii) fed during pregnancy with 6% olive oil- or 6% safflower oil-supplemented diets, enriched with PPAR ligands were studied. Maternal diabetes increased triglyceride concentrations and decreased expression of lipid-oxidizing enzymes in fetal lungs of diabetic rats, an expression further decreased by LTB4 and partially restored by 15dPGJ2 in lungs of male fetuses in the diabetic group. In lungs of female fetuses in the diabetic group, maternal diets enriched with olive oil increased triglyceride concentrations and fatty acid synthase expression, while those enriched with safflower oil increased triglyceride concentrations and fatty acid transporter expression. Both olive oil- and safflower oil-supplemented diets decreased cholesterol and cholesteryl ester concentrations and increased the expression of the reverse cholesterol transporter ATP-binding cassette A1 in fetal lungs of female fetuses of diabetic rats. In fetal lungs of control and diabetic rats, the proportion of polyunsaturated fatty acids increased with the maternal diets enriched with olive and safflower oils. Our results revealed important changes in lipid metabolism in fetal lungs of diabetic rats, and in the ability of PPAR ligands to modulate the composition of lipid species relevant in the lung during the perinatal period.

A systematic review and cost-effectiveness analysis of specialist services and adrenaline auto-injectors in anaphylaxis

BACKGROUND

Anaphylaxis is a severe, life-threatening generalised or systemic hypersensitivity reaction with high mortality. Specialist services (SSs) are believed to reduce anaphylaxis recurrence and improve use of adrenaline injectors (AIs), which can reduce mortality if used correctly and in time.

OBJECTIVES

To review the evidence on which persons are at high risk of anaphylactic episodes, the effects of history-taking (including signs, symptoms and physical examination) for anaphylaxis, and when (suspected) patients should be referred. To assess the cost-effectiveness of SS compared with standard care (SC) with or without prescription of AIs.

DATA SOURCES

In order to assess the clinical effectiveness, 10 databases [Cochrane Database of Systematic Reviews (CDSR), Cochrane Central Register of Controlled Trials (CENTRAL), Database of Abstracts of Reviews of Effects (DARE), Health Technology Assessment (HTA), NHS Economic Evaluation Database (NHS EED), Science Citation Index (SCI), Cumulative Index to Nursing and Allied Health Literature (CINAHL), EMBASE, MEDLINE, MEDLINE In-Process & Other Non-Indexed Citations, from inception up to March 2011] were searched without data restriction in order to identify relevant studies [randomised controlled trials (RCTs), controlled clinical trials, observational studies, prognostic studies using a multivariate model] written in English.

REVIEW METHODS

Standard review methods were applied for the assessment of clinical effectiveness. A Markov model, validated by clinical experts, was constructed, which modelled anaphylaxis according to trigger: either food, drug, insect or idiopathic. Anaphylaxis mortality was modelled as a function of time to die and time for emergency response. Probabilistic sensitivity analysis on key parameters was performed.

RESULTS

From the systematic review, 11,058 references were identified by the searches for studies assessing the clinical effectiveness. In total, 107 papers were obtained, and five prospective observational studies, including 1725 patients, were included. These studies estimated the risk of recurrence to be between 30% and 42.8%. In children (< 12 years), an overall recurrence of 27% was reported, with food being the most frequent allergen (71%). From the cost-effectiveness analysis (CEA), SC with injectors was dominated by SS with or without injectors. SS with no injectors would be cost-effective if the threshold for a quality-adjusted life-year (QALY) was greater than about £ 740 and with injectors would be cost-effective if the threshold was > £ 1800. These results were robust to all sensitivity analyses except at relatively extreme values of a small number of parameters.

LIMITATIONS

Limitations of the study include the low yield from the systematic review; in particular there were no good-quality studies of either SSs or AI effectiveness. This implied a great reliance on expert opinion in the CEA. However, this was appropriately addressed using sensitivity analysis.

CONCLUSIONS

Only five observational studies assessing clinical effectiveness were identified. Owing to the lack of good data to inform the effectiveness of anaphylaxis intervention, we recommend considerations of RCTs or at least well-designed observational studies of the components of care in SSs. The results of the CEA showed that SS with AIs was cost-effective at a threshold of £ 20,000 per QALY. More well-designed prospective studies on the effectiveness of SSs are needed to confirm these findings.

Hormonal manipulations in the 5-day timed artificial insemination protocol to optimize estrous cycle synchrony and fertility in dairy heifers

Objectives were to determine the effects of GnRH at the initiation of the 5-d timed artificial insemination (AI) program combined with 2 injections of PGF2α on ovarian responses and pregnancy per AI (P/AI) in dairy heifers, and the role of progesterone concentrations on LH release and ovulation in response to GnRH. In study 1, heifers received a controlled internal drug release (CIDR) insert containing 1.38 g of progesterone on d 0, an injection of 25 mg of PGF2α and CIDR removal on d 5, and an injection of 100 μg GnRH concurrently with AI on d 8. Heifers were assigned to receive no additional treatment (control; n=559) or an injection of GnRH on d 0 and a second injection of PGF2α on d 6 (G2P; n=547). In study 2, all heifers were treated as described for the control in study 1, and were allocated to receive no additional treatment (control; n=723), an injection of PGF2α on d 6 (NG2P; n=703), or an injection of GnRH on d 0 and an injection of PGF2α on d 6 (G2P; n=718). In study 3, heifers received a CIDR on d 7 after ovulation and were assigned randomly to a low-progesterone (LP; n=6) treatment in which 2 injections of 25 mg of PGF2α each were administered 12h apart, on d 7 and 7.5 after ovulation, or to a high-progesterone (HP; n=12) treatment in which no PGF2α was administered. On d 8, heifers received 100 μg of GnRH and blood was sampled at every 15 min from -30 to 180 min relative to the GnRH for assessment of LH concentrations. Additionally, 94 heifers were assigned to LP or HP and ovulation in response to GnRH was evaluated. In study 1, P/AI was greater for G2P than for the control on d 32 (59.4 vs. 53.5%) and 60 after AI (56.6 vs. 51.3%). In study 2, administration of GnRH on d 0 increased the proportion of heifers with a new corpus luteum on d 5 (control=21.9 vs. NG2P=20.1 vs. G2P=34.4%). Administration of a second PGF2α increased the proportion of heifers with progesterone <0.5 ng/mL at AI (control=83.1 vs. NG2P=93.0 and G2P=87.2%). Pregnancy per AI was greater for G2P than for control and NG2P on d 32 (control=52.9 vs. NG2P=55.0 vs. G2P=61.7%) and 60 (control=49.0 vs. NG2P=51.6 vs. G2P=59.1%). In study 3, HP attenuated LH release and reduced ovulation (19.0 vs. 48.4%) in response to GnRH compared with LP. Combining GnRH and 2 doses of PGF2α in the 5-d timed AI protocol improved follicle turnover, luteolysis, and P/AI in heifers. Elevated concentrations of progesterone suppressed LH release and are linked with the low ovulatory response to the initial GnRH treatment of the protocol.