Evaluation of the Brix refractometer to estimate immunoglobulin G concentration in bovine colostrum

Refractometry using a Brix refractometer has been proposed as a means to estimate IgG concentration in bovine maternal colostrum (MC). The refractometer has advantages over other methods of estimating IgG concentration in that the Brix refractometer is inexpensive, readily available, less fragile, and less sensitive to variation in colostral temperature, season of the year and other factors. Samples of first-milking MC were collected from 7 dairy farms in Maine, New Hampshire, Vermont, and Connecticut (n = 84) and 1 dairy farm in California (n = 99). The MC was milked from the cow at 6.1 ± 5.6 h postparturition and a sample was evaluated for Brix percentage by using an optical refractometer. Two additional samples (30 mL) were collected from the milk bucket, placed in vials, and frozen before analysis of total IgG by radial immunodiffusion (RID) using commercially available plates and by turbidimetric immunoassay (TIA). The second sample was analyzed for total bacterial counts and coliform counts at laboratories in New York (Northeast samples) and California (California samples). The Brix percentage (mean ± SD) was 23.8 ± 3.5, IgG concentration measured by RID was 73.4 ± 26.2 g/L, and IgG concentration measured by TIA was 67.5 ± 25.0 g/L. The Brix percentage was highly correlated (r = 0.75) with IgG analyzed by RID. The Brix percentage cut point to define high- or low-quality colostrum (50 g of IgG/L measured by RID) that classified more samples correctly given the proportion of high- (86%) and low-quality (14%) samples in this study was 21%, which is slightly lower than other recent estimates of Brix measurements. At this cut point, the test sensitivity, specificity, positive and negative predictive values, and accuracy were 92.9, 65.5, 93.5, 63.3, and 88.5%, respectively. Measurement of IgG by TIA correlated with Brix (r = 0.63) and RID (r = 0.87); however, TIA and RID methods of IgG measurement were not consistent throughout the range of samples tested. We conclude that Brix measurement of total solids in fresh MC is an inexpensive, rapid, and satisfactorily accurate method of estimating IgG concentration. A cut point of 21% Brix to estimate samples of MC \u3e50 g/L was most appropriate for our data. Measurement of IgG in MC by TIA differed from measurement by RID

Effect of milk replacer program on calf performance and digestion of nutrients with age of the dairy calf

Calves fed large amounts of milk replacer (MR) gain more body weight preweaning than calves fed less-aggressive programs; however, postweaning growth may be reduced. Limited research suggests that less than optimal digestion of the postweaned diet due to large amounts of MR with reduced dry feed intake preweaning may contribute to growth impairment postweaning. Current research was conducted to compare growth and postweaning digestion in 3-d-old male Holstein calves fed various MR programs. The MR programs were a conventional [CON; 0.44 kg of dry matter (DM) 21% crude protein (CP), 21% fat powder fed for 42 d], moderate (MOD; 0.66 kg of DM 27% CP, 17% fat powder fed for 42 d), and aggressive program (AGG; up to 0.87 kg of DM 27% CP, 17% fat powder fed for 49 d). All calves were fed a 20% CP textured starter and water ad libitum for 56 d. The trial used 96 calves (initially 41 ± 1.9 kg of body weight) received 5 wk apart in 2 groups of 48 calves. During d 51 to 56, fecal samples were collected from 5 calves per treatment randomly selected from calves in the first group. Selected nutrients and acid-insoluble ash (used as an internal flow marker) were analyzed in the starter and feces to estimate digestibility. Data were analyzed as a randomized complete block design with starting time of each group of calves as a block. Repeated measure analysis was performed on overall (0 to 56 d) data. Means were separated with a protected least significant difference test. Pen was the experimental unit. Calves fed CON had the least average daily gain [CON = 0.35, MOD = 0.51, and AGG = 0.55 kg/d; standard error of the mean (SEM) = 0.018], feed efficiency (CON = 0.35, MOD = 0.49, and AGG = 0.48 gain/feed, SEM = 0.016), and change in hip width (CON = 3.3, MOD = 4.1, and AGG = 4.1 cm, SEM = 0.20) compared with calves fed other programs. Calves fed AGG had the greatest change in BCS and least starter intake compared with calves fed the other programs. Digestibility of organic matter was 79, 78, and 68% and neutral detergent fiber was 54, 51, and 26% for calves fed programs CON, MOD, and AGG, respectively, and were least for calves fed AGG. These results indicate that postweaning digestion is lower than optimal and contributes to lower postweaning growth in calves fed aggressive compared with conventional or moderate MR programs

Inflammatory Pain Signals an Increase in Functional Expression of Organic Anion Transporting Polypeptide 1a4 at the Blood-Brain Barrier

Pain is a dominant symptom associated with inflammatory conditions. Pharmacotherapy with opioids may be limited by poor blood-brain barrier (BBB) permeability. One approach that may improve central nervous system (CNS) delivery is to target endogenous BBB transporters such as organic anion-transporting polypeptide 1a4 (Oatp1a4). It is critical to identify and characterize biological mechanisms that enable peripheral pain/inflammation to “transmit” upstream signals and alter CNS drug transport processes. Our goal was to investigate, in vivo, BBB functional expression of Oatp1a4 in animals subjected to peripheral inflammatory pain. Inflammatory pain was induced in female Sprague-Dawley rats (200–250 g) by subcutaneous injection of 3% λ-carrageenan into the right hind paw; control animals were injected with 0.9% saline. In rat brain microvessels, Oatp1a4 expression was increased during acute pain/inflammation. Uptake of taurocholate and [d-penicillamine2,5]-enkephalin, two established Oatp substrates, was increased in animals subjected to peripheral pain, suggesting increased Oatp1a4-mediated transport. Inhibition of inflammatory pain with the anti-inflammatory drug diclofenac attenuated these changes in Oatp1a4 functional expression, suggesting that inflammation in the periphery can modulate BBB transporters. In addition, diclofenac prevented changes in the peripheral signaling cytokine transforming growth factor-β1 (TGF-β1) levels and brain microvascular TGF-β receptor expression induced by inflammatory pain. Pretreatment with the pharmacological TGF-β receptor inhibitor 4-[4-(1,3-benzodioxol-5-yl)-5-(2-pyridinyl)-1H-imidazol-2-yl]benzamide (SB431542) increased Oatp1a4 functional expression in λ-carrageenan-treated animals and saline controls, suggesting that TGF-β signaling is involved in Oatp1a4 regulation at the BBB. Our findings indicate that BBB transporters (i.e., Oatp1a4) can be targeted during drug development to improve CNS delivery of highly promising therapeutics

Oxidative stress increases blood–brain barrier permeability and induces alterations in occludin during hypoxia–reoxygenation

The blood–brain barrier (BBB) has a critical role in central nervous system homeostasis. Intercellular tight junction (TJ) protein complexes of the brain microvasculature limit paracellular diffusion of substances from the blood into the brain. Hypoxia and reoxygenation (HR) is a central component to numerous disease states and pathologic conditions. We have previously shown that HR can influence the permeability of the BBB as well as the critical TJ protein occludin. During HR, free radicals are produced, which may lead to oxidative stress. Using the free radical scavenger tempol (200 mg/kg, intraperitoneal), we show that oxidative stress produced during HR (6% O2 for 1 h, followed by room air for 20 min) mediates an increase in BBB permeability in vivo using in situ brain perfusion. We also show that these changes are associated with alterations in the structure and localization of occludin. Our data indicate that oxidative stress is associated with movement of occludin away from the TJ. Furthermore, subcellular fractionation of cerebral microvessels reveals alterations in occludin oligomeric assemblies in TJ associated with plasma membrane lipid rafts. Our data suggest that pharmacological inhibition of disease states with an HR component may help preserve BBB functional integrity

sj-doc-2-jia-10.1177_23259582231210801 - Supplemental material for Short-Form HIV Disability Questionnaire Sensibility, Utility, and Implementation Considerations in Community-Based Settings: A Mixed Methods Study

Supplemental material, sj-doc-2-jia-10.1177_23259582231210801 for Short-Form HIV Disability Questionnaire Sensibility, Utility, and Implementation Considerations in Community-Based Settings: A Mixed Methods Study by Kelly K. O’Brien, Francisco Ibáñez-Carrasco, Patricia Solomon, Soo Chan Carusone, Ann Stewart, Ahmed M. Bayoumi, Darren A. Brown, Adria Quigley, Puja Ahluwalia, Kristine M. Erlandson, Jaime H. Vera, Colm Bergin, Steven E. Hanna, Marilyn Swinton, Brittany Torres, Kiera McDuff, George Da Silva, Glen Bradford, Shaz Islam, Colleen Price, Joanne D. Lindsay, Carolann Murray, Natalia McClellan, Katrina Krizmancic, Praney Anand, Tammy Yates, Rosalind Baltzer Turje, Patrick McDougall, Vladislava Vlatka Maksimcev and Richard Harding in Journal of the International Association of Providers of AIDS Care (JIAPAC)</p

sj-doc-1-jia-10.1177_23259582231210801 - Supplemental material for Short-Form HIV Disability Questionnaire Sensibility, Utility, and Implementation Considerations in Community-Based Settings: A Mixed Methods Study

Supplemental material, sj-doc-1-jia-10.1177_23259582231210801 for Short-Form HIV Disability Questionnaire Sensibility, Utility, and Implementation Considerations in Community-Based Settings: A Mixed Methods Study by Kelly K. O’Brien, Francisco Ibáñez-Carrasco, Patricia Solomon, Soo Chan Carusone, Ann Stewart, Ahmed M. Bayoumi, Darren A. Brown, Adria Quigley, Puja Ahluwalia, Kristine M. Erlandson, Jaime H. Vera, Colm Bergin, Steven E. Hanna, Marilyn Swinton, Brittany Torres, Kiera McDuff, George Da Silva, Glen Bradford, Shaz Islam, Colleen Price, Joanne D. Lindsay, Carolann Murray, Natalia McClellan, Katrina Krizmancic, Praney Anand, Tammy Yates, Rosalind Baltzer Turje, Patrick McDougall, Vladislava Vlatka Maksimcev and Richard Harding in Journal of the International Association of Providers of AIDS Care (JIAPAC)</p