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Asian grapevine leaf rust, caused by

Scientific communication is facilitated by a data-driven, scientifically sound taxonomy that considers the end-user's needs and established successful practice. In 2013, the

The objective of this study was to evaluate the influence of metabolizable protein (MP) level and supplemental rumen-protected methionine (RPM) on colostrum quality and passive immunity transfer from beef cows fed during late-gestation. One hundred and forty-seven pregnant Angus crossbred cows and heifers were randomly assigned to one of six dietary treatments based on a 3 x 2 factorial arrangement. Diets included feeding to 90%, 100% and 110% MP requirements (NRC, 2016), offered with (without) 9 g/d of RPM. Cattle were individually fed a partially mixed ration (60% haylage/40% straw for cows; 70% haylage/30% straw for heifers) with supplements top-dressed daily for approximately 56 d prior to calving. Immediately after calving, a colostrum sample was collected from each dam for analysis of milk components, total protein, and IgG concentrations. Two d post-calving, serum samples were collected from each calf for analysis of total protein and IgG concentrations. A refractometer was used to estimate total protein as a preliminary estimate of the transfer of maternal IgG and total IgG concentrations were later determined using Radial Immunodiffusion (RID). Data were analyzed as a completely randomized block design using Proc GLIMMIX in SAS. Level of MP, RPM, and their interaction did not influence concentrations of fat, protein, BHB or SCC in colostrum (P ≥ 0.12). Supplementation of RPM decreased concentrations of MUN (45.92 vs. 54.51 ±3.17 mg/dl; P = 0.04), but did not change IgG (14.66 vs. 15.90 ±0.87 g/dl; P = 0.29). While MP level during gestation did not affect total protein or IgG concentrations in calf serum (P ≥ 0.64), providing supplemental RPM decreased total protein (5.79 vs. 6.33 ±0.13 g/dl; P = 0.002) and IgG concentrations in calf serum (3.44 vs. 4.30 ±0.25 g/dl; P = 0.01). These results suggest that providing supplemental methionine for beef cows during gestation may alter colostrum quality and decrease serum protein and IgG in offspring.

A three-way factorial arrangement was used to assess impacts of protein/methionine nutrition during gestation and two lactational management systems on performance of cow-calf pairs pre-weaning. 140 crossbred beef cows were managed in drylot and randomly assigned to one of six nutritional treatments during the third trimester of gestation. Cows were fed to meet 110% (HP), 100% (MP), or 90% (LP) of metabolizable protein requirements for late-gestation (NRC, 2016), with(without) rumen-protected methionine (RPM) for 8 weeks prior to parturition. Post-partum, cow-calf pairs were managed in drylot (DL) and fed ad libitum, a ration formulated to meet lactational nutrient requirements, or rotationally grazed on pasture (PAS). Cow body weights (BW) and body condition scores (BCS) and calf BW were recorded at regular intervals. All data were analyzed using PROC GLIMMIX (SAS v9.4). HP cows were heaviest at calving (P = 0.02), but calf birthweight was unaffected by gestational nutrition (P > 0.19). Gestational nutrition did not impact cow conception rate (CR), or calf BW and ADG (P > 0.17). Lactational management system (PAS, DL) did not affect cow BCS or CR (P > 0.13), but impacted cow and calf BW and ADG. PAS calves were heavier, had greater ADG, and heavier weaning BW than DL calves (P < 0.02). This came at the expense of BW loss throughout lactation and lower ADG for PAS cows, versus BW gains and greater ADG for DL cows (P < 0.0001). An interaction between protein level and RPM supplementation was present for cow BW at calving and weaning, and BW change throughout lactation (P < 0.04), with tendencies for interactions for cow ADG and BCS (P < 0.09). Overall, prepartum protein/methionine supplementation did not affect calf performance prior to weaning, but may have affected cow performance during lactation. Rotationally grazing cow-calf pairs on pasture improved pre-weaning calf gains, but reduced cow gains throughout lactation.

The objective of this study was to determine effect of ruminal acidosis (RA) and low feed intake [LFI] on the regional barrier function of the gastrointestinal tract. Twenty-one Holstein steers were fed for ad libitum intake for 5 d (control [CON]), fed at 25% of ad libitum intake for 5 d (LFI), or provided 2 d of ad libitum intake followed by 1-d of feed restriction (25% of ad libitum intake), 1 d where 30% of ad libitum dry matter intake (DMI) was provided as pelleted barley followed by the full allocation (RA) and fed for ad libitum intake the following day. Tissues and digesta from the rumen, omasum, duodenum, jejunum, ileum, cecum, proximal, and distal colon were collected. Permeability was assessed using the mucosal-to-serosal flux of inulin (JMS-inulin) and mannitol (JMS-mannitol). Digesta pH was 0.81, 0.63, and 0.42 pH units less for RA than CON in the rumen, cecum, and proximal colon; while, LFI had pH that was 0.47 and 0.36 pH units greater in the rumen and proximal colon compared to CON. Total ruminal short-chain fatty acid (SCFA) concentration were less for LFI (92 mM; P = 0.010) and RA (87 mM; P = 0.007) than CON (172 mM) steers. In the proximal colon, the proportion of butyrate (P = 0.025 and P = 0.022) and isobutyrate (P = 0.019 and P = 0.019) were greater, and acetate (P = 0.028 and P = 0.028) was less for LFI and RA, respectively, when compared to CON steers. Ruminal papillae length, width, perimeter, and surface area were 1.21 mm, 0.78 mm, 3.84 mm, and 11.15 mm2 less for LFI than CON; while, RA decreased papillae width by 0.52 mm relative to CON. The JMS-mannitol was less for LFI steers than CON in the proximal colon (P = 0.041) and in the distal colon (P = 0.015). Increased gene expression for claudin 1, occludin, tight-cell junction protein 1 and 2, and toll-like receptor 4 were detected for LFI relative to CON in the rumen, jejunum, and proximal colon. For RA steers, expression of toll-like receptor 4 in the rumen, and occludin and tight-cell junction protein 1 were greater in the jejunum than CON. An acute RA challenge decreased pH in the rumen and large intestine but did not increase tissue permeability due to increases in the expression of genes related to barrier function within 1 d of the challenge. Steers exposed to LFI for 5 d had reduced ruminal SCFA concentrations, smaller ruminal papillae dimensions, and increased tissue permeability in the proximal and distal colon despite increases for genes related to barrier function and immune function.

Background Manipulating maternal nutrition during specific periods of gestation can result in re-programming of fetal and post-natal development. In this experiment we investigated how a feed restriction of 85% compared with 140% of total metabolizable energy requirements, fed to cows during mid-to-late gestation, influences phenotypic development of fetuses and mRNA expression of growth (Insulin-Like Growth Factor family and Insulin Receptor (INSR)), myogenic (Myogenic Differentiation 1 (MYOD1), Myogenin (MYOG), Myocyte Enhancer Factor 2A (MEF2A), Serum Response Factor (SRF)) and adipogenic (Peroxisome Proliferator Activated Receptor Gamma (PPARG)) genes in fetal longissimus dorsi (LD) and semitendinosus (ST) muscle. DNA methylation of imprinted genes, Insulin Like Growth Factor 2 (IGF2) and Insulin Like Growth Factor 2 Receptor (IGF2R), and micro RNA (miRNA) expression, were also examined as potential consequences of poor maternal nutrition, but also potential regulators of altered gene expression patterns. Results While the nutrient restriction impacted dam body weight, no differences were observed in phenotypic fetal measurements (weight, crown-rump length, or thorax circumference). Interestingly, LD and ST muscles responded differently to the differential pre-natal nutrient levels. While LD muscle of restricted fetal calves had greater mRNA abundances for Insulin Like Growth Factor 1 and its receptor (IGF1 and IGF1R), IGF2R, INSR, MYOD1, MYOG, and PPARG, no significant differences were observed for gene expression in ST muscle. Similarly, feed restriction had a greater impact on the methylation level of IGF2 Differentially Methylated Region 2 (DMR2) in LD muscle as compared to ST muscle between treatment groups. A negative correlation existed between IGF2 mRNA expression and IGF2 DMR2 methylation level in both LD and ST muscles. Differential expression of miRNAs 1 and 133a were also detected in LD muscle. Conclusions Our data suggests that a nutrient restriction of 85% as compared to 140% of total metabolizable energy requirements during the 2nd half of gestation can alter the expression of growth, myogenic and adipogenic genes in fetal muscle without apparent differences in fetal phenotype. It also appears that the impact of feed restriction varies between muscles suggesting a priority for nutrient partitioning depending on muscle function and/or fiber composition. Differences in the methylation level in IGF2, a well-known imprinted gene, as well as differences in miRNA expression, may be functional mechanisms that precede the differences in gene expression observed, and could lead to trans-generational epigenetic programming.

Agri-food supply chains in North America have become remarkably efficient, supplying an unprecedented variety of items at the lowest possible cost. However, the initial stages of the COVID-19 pandemic and the near-total temporary loss of the foodservice distribution channel, exposed a vulnerability that many found surprising. Instead of continued shortages, however, the agri-food sector has since moved back to near normal conditions with prices and production levels similar to those typically observed in years prior to the pandemic. Ironically, the specialization in most food supply chains designed for “just-in-time” delivery to specific customers with no reserve capacity, which led to the initial disruptions, may have also been responsible for its rapid rebound. A common theme in assessing the impacts across the six commodities examined is the growing importance of understanding the whole supply chain. Over the longer term, a continuation of the pandemic could push the supply chain toward greater consolidation of firms and diversification of products given the increasing option value of maintaining flexibility. Other structural changes will be felt through input markets, most notably labour, as the trend toward greater automation will continue to accelerate as a response to meeting concerns about a consistent supply of healthy and productive workers. The economic fall out from the pandemic may lead to greater concentration in the sector as some firms are not able to survive the downturn and changes in consumer food buying behaviour, including movement toward online shopping and enhanced demand for attributes associated with resiliency, such as local. On the other hand, online shopping may provide opportunities for small producers and processors to shorten supply chains and reach customers directly. In the long term, COVID-19 impacts on global commerce and developing country production are more uncertain and could influence poverty reduction. While COVID-19's impacts on North American agriculture should have minimal effect on the Sustainable Development Goals (SDGs) through food prices, the ongoing global trends in trade and agribusiness accelerated by the pandemic are relevant for achievement of the SDGs., Highlights • Initial stages of the COVID-19 pandemic exposed a vulnerability in agri-food sector supply chains. • Most sectors have since moved back to near normal conditions. • Importance of understanding the whole supply chain is growing. • The trend toward greater automation will continue to accelerate.

The objective of this study was to investigate the role of protein-mediated transport pathways for short-chain fatty acid flux across the ruminal epithelium, using subacute ruminal acidosis (SARA) and feed restriction as models. Twenty-one Holstein steers (216.8 ± 31.4 kg BW) were individually housed and fed a total mixed ration (TMR) with a 50:50 forage:concentrate ad libitum for 5 d. After the 5 d diet adjustment period, calves were assigned 1 of 3 treatments: control (CTRL) calves were fed the TMR ad libitum on d 1, subacute ruminal acidosis calves were given 25% of their ad libitum DMI on d 1 and then given a barley grain challenge at 30% of ad libitum DMI on d2 (ACID) calves were given 25% of their ad libitum DMI on d 1 and then given a barley grain challenge at 30% of ad libitum DMI on d 2, and feed restriction (FR) calves were given 25% of their ad libitum DMI for 5 d. Reticuloruminal pH was continuously measured during the entire study. At the end of the study, rumen tissue was harvested and acetate and butyrate flux were measured. Selective inhibitors were used to differentiate total flux (TOTAL), protein-mediated flux (PMF), and passive diffusion flux (PDF). The duration that rumen pH was

The objectives of this study were to determine the effect of dietary inclusion [0%–50% of diet dry matter (DM)] and form (dry and modified wet) of corn distillers grains plus solubles (DGS) on pancreatic α-amylase and trypsin activities in calves. Feeding up to 50% DGS did not negatively impact pancreatic exocrine function.

In a 4 × 4 Latin square design (24-d periods), 4 ruminally cannulated Hereford × Angus/Simmental heifers were used to evaluate the effect of increasing levels of monensin concentration on DMI, ruminal fermentation, short-chain fatty acid (SCFA) absorption across the reticulorumen, and total tract barrier function. Heifers were fed a barley-based finishing diet (76% rolled barley grain, 12% barley silage, 8% mineral and vitamin supplement, and 4% canola meal) containing 0, 22, 33 or 48 mg/kg monensin. Urinary recovery of Cr-EDTA was used as an indicator of total tract barrier function (d 18 to 20). Days 20 to 23 were used to evaluate ruminal fermentation and total tract digestibility measurements, and SCFA absorption was measured using the temporarily isolated and washed reticulorumen technique on d 24. Data were analyzed using PROC MIXED of SAS with linear and quadratic contrasts to evaluate the effect of increasing monensin dose. Increasing monensin linearly decreased DMI (10.0, 9.9, 9.3, and 9.1 kg/d for diets containing 0, 22, 33 or 48 mg/kg monensin, respectively; = 0.01) but did not affect the variation in DMI among days. Urinary Cr-EDTA recovery was not ( ≥ 0. 61) affected by increasing dose of monensin, nor was ruminal pH (mean, minimum, maximum, duration less than 5.5, and area under curve; ≥ 0.21). The acetate-to-propionate ratio linearly decreased (1.9, 1.8, 1.4, and 1.3 for diets containing 0, 22, 33 or 48 mg/kg monensin, respectively; = 0.03) with increasing monensin. There was no response ( ≥ 0. 17) for the rate of SCFA absorption with monensin concentration. Total tract ethanol soluble carbohydrate digestibility linearly increased (77.2, 84.7, 88.0, and 94.0% for diets containing 0, 22, 33 or 48 mg/kg monensin, respectively; = 0.003) whereas starch digestibility quadratically responded (93.8, 93.9, 88.0, and 94.0% for diets containing 0, 22, 33 or 48 mg/kg monensin, respectively; < 0.001), where 33 mg/kg inclusion of monensin had a minimal value. The results from this study indicate that in addition to the known effects of monensin to reduce DMI and the acetate:propionate ratio, monensin inclusion does not affect ruminal pH, SCFA absorption, or total tract barrier function.

Fourteen Holstein bull calves were used in a randomized complete block design to investigate the effect of calf age and weaning on permeability of the gastrointestinal tract (GIT). Calves were randomly assigned to 1 of 2 treatments: (1) a weaning protocol that was initiated on d 35; WN; n=7), or (2) a control treatment where calves were not weaned (CON; n=7). Calves were bottle-fed milk replacer (150 g/L), in 3 equal portions/d targeting 15% of their body weight (BW) in liquid milk intake [approximately 21.1g/kg of BW/d, dry matter (DM) basis]. On d 35, the amount of milk replacer offered to WN calves was reduced to 7.5% of BW for 7 d before calves were weaned on d 42. On d 14, 28, and 42, calves were orally dosed with 500 mL of Cr-EDTA (179 mM Cr-EDTA solution) and housed in a metabolism crate to enable total urine collection and determination of total urinary Cr recovery as an indicator of total-tract permeability. On d 44, calves were killed and tissues from the rumen, omasum, duodenum, jejunum, ileum, cecum, and proximal and distal colon were collected, rinsed, and transported in buffer solution (pH 7.4 at 38.5°C). Tissues were incubated in Ussing chambers under short-circuit conditions with buffer solutions designed to mimic the mucosal and serosal energy source that would be available in vivo (glucose for tissues from the small intestine and short-chain fatty acids for tissues that would be exposed to fermentation; rumen, omasum, and large intestinal tissues). The serosal to mucosal flux of (14)C-mannitol and (3)H-inulin was measured for each region. Although we detected treatment × period interactions for BW and starter intake, dietary treatments did not differ within a week. Overall, the time that ruminal pH was5.5 was less before weaning than after weaning. We observed a differential response for the appearance of Cr in urine for WN and CON calves, where the appearance of Cr (mg/48 h) in urine decreased for both treatments from d 14 to 28, but increased from d 28 to 42 for WN, whereas Cr appearance continued to decrease for CON. The flux of mannitol and inulin did not differ between treatments but did differ among region of the GIT, with rumen, duodenum, and jejunum having the greatest permeability. These data suggest that permeability of the GIT decreases with age but weaning may disrupt this process. The rumen, duodenum, and jejunum appear to be the regions with greatest permeability.

Salim, H., Wood, K. M., Cant, J. P. and Swanson, K. C. 2015. Influence of feeding increasing levels of dry or modified wet corn distillers’ grains plus solubles in whole corn grain-based finishing diets on hepatic and renal mass, and glutathione peroxidase and urea cycle enzyme activities in finishing cattle. Can. J. Anim. Sci. 95: 407–415. Forty-two cross-bred steers (BW=357±5.8 kg) fed whole corn grain-based finishing diets were used in a completely randomized block (60, 120, or 180 d on feed) design (2×3 factorial arrangement of treatments plus control) to determine the effect of inclusion level [0 (control), 16.7, 33.3, and 50% of diet DM) and form (dry (DDGS) or modified wet (MWDGS)] of distillers’ grains plus solubles (DGS) on hepatic and renal glutathione peroxidase (GPx) and hepatic urea cycle enzyme activities. Kidney weight (g kg−1of BW) increased linearly (P=0.004) with increasing inclusion levels of DGS. There were no effects (P≥0.11) of dietary treatment on hepatic and renal GPx activity (U g−1, U mg−1of protein, and kU liver−1). Hepatic carbamoyl phosphate synthetase activity (kU liver−1and U kg−1of BW) tended to linearly increase (P=0.09 and P=0.10, respectively) with increasing inclusion level of DGS. Hepatic ornithine transcarbamoylase and argininosuccinate synthetase activity (kU liver−1and U kg−1of BW) increased linearly (P≤0.05) with increasing inclusion levels of DGS. These data indicate that steers adapt to feeding up to 50% DGS by increasing kidney mass and activity of urea cycle enzymes in liver to allow for clearance of excess nitrogen. Also, hepatic and renal GPx activity, as an indicator of Se status, is not affected when typical finishing diets are fed.

Wood, K. M., Montanholi, Y. R., Fitzsimmons, C. F., Miller, S. P., McBride, B. W. and Swanson, K. C. 2014. Characterization and evaluation of residual feed intake measured in mid- to late-gestation mature beef cows and relationships with circulating serum metabolites and linear body measurements. Can. J. Anim. Sci. 94: 499–508. To evaluate the use of residual feed intake (RFI) models measured in mid-to-late gestating beef cows, a dataset was used combining data from five experiments containing nine treatment and/or replicate groups for a total of 321 animal records. Investigations of RFI models included the effects of age, ultrasound measures of body composition, pregnancy corrected gain, and dietary treatment group. A subset of animals had serum analyzed for circulating metabolites (glucose, non-esterified fatty acids, urea, beta-hydroxybutyrate; n=227) and/or linear body measures (hip height and width, body length, body circumference at the heart, mid-body and at flank; n=114) for correlation analysis w...

In mid-to-late gestation, nutrient demand increases to meet the growth requirements of the conceptus and cows may alter metabolism in response to energy demands of pregnancy. By better understanding the metabolic role of pregnancy, there may be opportunities to better understand maintenance energy costs and improve overall feed efficiency. Eighteen mature Simmental/Angus crossbred cows, pregnant (PREG; n = 9) and nonpregnant (OPEN; n = 9), were used to investigate the effect of pregnancy on BW change, carcass traits, visceral organ mass, and circulating serum metabolites. Cows were blocked by day of expected parturition such that each block was slaughtered 4 to 5 wk before parturition. Cows were individually fed for ad libitum intake using Calan gates for 89 to 105 d. Cows were weighed, ultrasounded for rib (over the 12th and 13th rib) and rump fat, and a serum sample obtained at d 1, 56, and 3 to 5 d before slaughter. At slaughter, organs were removed, trimmed of fat, and weighed. Serum was analyzed for β-hydroxybutyrate (BHBA), NEFA, glucose, urea, total cholesterol, and triiodothyronine (T3). Tissue samples from liver, kidney, sternomandibularis muscle, ruminal papillae, pancreas, and small intestinal mucosa were collected at slaughter and snap frozen in liquid N. Western blots were conducted to quantify abundance of: proliferating cell nuclear antigen (PCNA), ATP synthase, ubiquitin, and Na(+)/K+ ATPase for all tissues; PPARγ, PPARγ coactivator 1α (PGC1-α), 5'-adenosine monophosphate-activated protein kinase (AMPK) and phosphorylated-AMPK (pAMPK) for liver, muscle, and rumen; phosphoenolpyruvate carboxykinase (PEPCK) for liver and kidney; and uncoupling protein 2 (UCP2) for liver. Data were analyzed using PROC MIXED in SAS as a replicated randomized complete block. Liver weights (actual, relative to BW, relative to HCW) were heavier (P ≤ 0.02) in OPEN. Rumen mass and kidney fat weight, both relative to BW, were also greater (P ≤ 0.04) in OPEN. On d 56 and at preslaughter, PREG cows had greater (P ≤ 0.04) BHBA, NEFA and urea concentrations and lower (P = 0.04) cholesterol concentration. Hepatic Na(+)/K+ ATPase abundance was greater (P = 0.04) in PREG cows. In rumen papillae, abundance of pAMPKα was increased (P = 0.006) in PREG cows. These data indicate that PREG cows may metabolize energy reserves and alter their metabolism to meet the energetic demands of the growing fetus.

Twenty-two nonlactating multiparous pregnant beef cows (639 ± 68 kg) were used to investigate the effect of dietary restriction on the abundance of selected proteins regulating cellular energy metabolism. Cows were fed at either 85% (n = 11; LOW) or 140% (n = 11; HIGH) of total NE requirements. The diet consisted of a haylage-based total mixed ration containing 20% wheat straw. Cows were slaughtered by block (predicted date of parturition), beginning 83 d after the initiation of dietary treatments and every week thereafter for 6 wk, such that each block was slaughtered at approximately 250 d of gestation. Tissue samples from liver, kidney, sternomandibularis muscle, ruminal papilli (ventral sac), pancreas, and small intestinal muscosa were collected at slaughter and snap frozen in liquid N2. Western blots were conducted to quantify abundance of proliferating cell nuclear antigen (PCNA), ATP synthase, ubiquitin, and Na/K+ ATPase for all tissues; PPARγ, PPARγ coactivator 1 α (PGC-1α), and 5´-adenosine monophosphate-activated protein kinase (AMPK) and the activated form phosphorylated-AMPK (pAMPK) for liver, muscle, and rumen; phosphoenolpyruvate carboxykinase (PEPCK) for liver and kidney; and uncoupling protein 2 (UCP2) for liver. Statistical analysis was conducted using Proc Mixed in SAS and included the fixed effects of dietary treatment, cow age, block, and the random effect of pen. Dietary treatments resulted in cows fed HIGH having greater (P ≤ 0.04) ADG and final BW than cows fed LOW. Abundance of ubiquitin in muscle was greater (P = 0.009) in cows fed LOW, and PCG-1 α in liver was greater (P = 0.03) in cows fed HIGH. Hepatic O2 consumption was greater in HIGH (P ≤ 0.04). Feed intake can influence the abundance of important metabolic proteins and suggest that protein degradation may increase in muscle from moderately nutrient restricted cows and that energy metabolism in liver increases in cows fed above NE requirements.

To determine effects of pregnancy (experiment 1) and plane of nutrition during pregnancy (experiment 2) on pancreatic digestive enzymes and morphology of insulin-containing cell clusters, beef cows...

In a 4 × 4 Latin square design (24-d periods), 4 ruminally cannulated Hereford × Angus/Simmental heifers were used to evaluate the effect of increasing levels of monensin concentration on DMI, ruminal fermentation, short-chain fatty acid (SCFA) absorption across the reticulorumen, and total tract barrier function. Heifers were fed a barley-based finishing diet (76% rolled barley grain, 12% barley silage, 8% mineral and vitamin supplement, and 4% canola meal) containing 0, 22, 33 or 48 mg/kg monensin. Urinary recovery of Cr-EDTA was used as an indicator of total tract barrier function (d 18 to 20). Days 20 to 23 were used to evaluate ruminal fermentation and total tract digestibility measurements, and SCFA absorption was measured using the temporarily isolated and washed reticulorumen technique on d 24. Data were analyzed using PROC MIXED of SAS with linear and quadratic contrasts to evaluate the effect of increasing monensin dose. Increasing monensin linearly decreased DMI (10.0, 9.9, 9.3, and 9.1 kg/d for diets containing 0, 22, 33 or 48 mg/kg monensin, respectively; = 0.01) but did not affect the variation in DMI among days. Urinary Cr-EDTA recovery was not ( ≥ 0. 61) affected by increasing dose of monensin, nor was ruminal pH (mean, minimum, maximum, duration less than 5.5, and area under curve; ≥ 0.21). The acetate-to-propionate ratio linearly decreased (1.9, 1.8, 1.4, and 1.3 for diets containing 0, 22, 33 or 48 mg/kg monensin, respectively; = 0.03) with increasing monensin. There was no response ( ≥ 0. 17) for the rate of SCFA absorption with monensin concentration. Total tract ethanol soluble carbohydrate digestibility linearly increased (77.2, 84.7, 88.0, and 94.0% for diets containing 0, 22, 33 or 48 mg/kg monensin, respectively; = 0.003) whereas starch digestibility quadratically responded (93.8, 93.9, 88.0, and 94.0% for diets containing 0, 22, 33 or 48 mg/kg monensin, respectively;0.001), where 33 mg/kg inclusion of monensin had a minimal value. The results from this study indicate that in addition to the known effects of monensin to reduce DMI and the acetate:propionate ratio, monensin inclusion does not affect ruminal pH, SCFA absorption, or total tract barrier function.

Sixty cross-bred steers (Angus ×; n = 36 and Charolais ×; n = 24) were used in a split-plot design to investigate the effects of feeding corn (Zea mays) or sorghum (Sorghum bicolor) dried distillers grains plus solubles in growing and finishing diets on growth performance and carcass traits. Steers were randomly assigned to one of three dietary treatments used in both feeding periods: a control diet containing soybean meal (n = 20; CON), a diet containing 200 g/kg (DM basis) corn dried distillers grains + solubles (n = 20; CDDGS) and a diet containing 200 g/kg (DM basis) sorghum dried distillers grains + solubles (n = 20; SDDGS). Steers were fed a corn silage (CS) based grower diet (∼750/kg CS) for 56 d and then switched to a high grain finisher diet (150 g/kg CS). Feed intakes were measured using Insentec (n = 48) and Calan gate (n = 12) feeding systems. Animals were weighed every 28 d and slaughtered at an estimated backfat of 10 mm as estimated by ultrasound. Total trial average daily gain (ADG) was 1.56 kg/d ± 0.04 for CON, 1.54 kg/d ± 0.04 for CDDGS, and 1.51 kg/d ± 0.04 for SDDGS and did not differ (P>0.68) between treatments. Dietary treatment did not affect (P>0.14) dry matter intake (DMI) in the growing phase, although ADG was lower for SDDGS vs. CON (P=0.008) and CDDGS (P=0.02). There was a lower gain:feed in the growing phase for SDDGS vs. CDDGS (P=0.04). In the finishing phase, inclusion of corn or sorghum DDGS did not affect (P>0.41) ADG, DMI or G:F. However, fewer days on feed were required for SDDGS to reach the target backfat for slaughter than CDDGS (P=0.03) and CON (P=0.05). These results indicate that sorghum dried distillers grains plus solubles can be included at 200 g/kg inclusion level, similar to corn distillers grains plus solubles, in grower and finisher diets, without negatively influencing overall growth or carcass traits, although feeding SDDGS may result in reduced performance when corn silage based diets are fed and results in earlier fattening at a lighter body weight.

Seventy-one individually fed multiparous, pregnant crossbred beef cows [body weight (BW) ± SD; 730 ± 77.9 kg] were used to examine the effects of including crop residues in alfalfa/grass haylage-based rations on BW gain, fat deposition/loss and plasma metabolites. The haylage control ration (CON; n = 23) was modified to include either 40% (dry matter basis) wheat straw (WS; n = 24) or 40% corn stalklage (CS; n = 24). Cows were blocked by calving date and randomly assigned to each treatment and fed for 82 d leading up to the earliest calving date. On days 1, 40, and 82, cows were weighed, ultrasounded to measure subcutaneous backfat (BF) over the ribs, body condition scored (BCS) and plasma was collected. Calves from cows fed WS had greater (P = 0.02 ) weaning weights than cows fed CS, but did not differ (P = 0.23) from CON. CS cows had the lowest ADG (P

Twenty-four steers (initial body weight = 535 ± 5.0 kg) predominately of Angus breeding were used to determine the effect of dietary corn silage inclusion [20, 40, 60, or 80% of dry matter (DM)] on visceral mass, cellularity, and the protein expression of ATP synthase, Na+/K+-ATPase, proliferating cell nuclear antigen (PCNA) and ubiquitin. Steers were fed at similar energy levels (2.1 × NEm requirement). There were no significant treatment effects on specific visceral organ weights. Hepatic Na+/K+-ATPase expression linearly increased (P = 0.01) and ruminal Na+/K+-ATPase expression linearly decreased (P = 0.01) with increasing corn silage inclusion. Hepatic PCNA expression was quadratically affected (P = 0.05) with a decrease when corn silage inclusion increased from 20 to 60%, and an increase when corn silage inclusion increased from 60 to 80%. Renal ATP synthase (P = 0.02) and ubiquitin expression (P = 0.01) were quadratically affected in a similar pattern with an increase when corn silage inclusion increased from 20 to 60%, and a decrease when corn silage inclusion increased from 60 to 80%. These results indicate that different dietary corn silage inclusions, at similar dietary energy intake, may alter rumen, liver, and kidney energy expenditure, at least in part, through changes in specific metabolism rather than mass. Key words: Corn silage inclusion, visceral organ mass, cellular energy metabolism, steer

In mid-to-late gestation, nutrient demand increases to meet the growth requirements of the conceptus and cows may alter metabolism in response to energy demands of pregnancy. By better understanding the metabolic role of pregnancy, there may be opportunities to better understand maintenance energy costs and improve overall feed efficiency. Eighteen mature Simmental/Angus crossbred cows, pregnant (PREG; n = 9) and nonpregnant (OPEN; n = 9), were used to investigate the effect of pregnancy on BW change, carcass traits, visceral organ mass, and circulating serum metabolites. Cows were blocked by day of expected parturition such that each block was slaughtered 4 to 5 wk before parturition. Cows were individually fed for ad libitum intake using Calan gates for 89 to 105 d. Cows were weighed, ultrasounded for rib (over the 12th and 13th rib) and rump fat, and a serum sample obtained at d 1, 56, and 3 to 5 d before slaughter. At slaughter, organs were removed, trimmed of fat, and weighed. Serum was analyzed for β-hydroxybutyrate (BHBA), NEFA, glucose, urea, total cholesterol, and triiodothyronine (T3). Tissue samples from liver, kidney, sternomandibularis muscle, ruminal papillae, pancreas, and small intestinal mucosa were collected at slaughter and snap frozen in liquid N. Western blots were conducted to quantify abundance of: proliferating cell nuclear antigen (PCNA), ATP synthase, ubiquitin, and Na(+)/K+ ATPase for all tissues; PPARγ, PPARγ coactivator 1α (PGC1-α), 5'-adenosine monophosphate-activated protein kinase (AMPK) and phosphorylated-AMPK (pAMPK) for liver, muscle, and rumen; phosphoenolpyruvate carboxykinase (PEPCK) for liver and kidney; and uncoupling protein 2 (UCP2) for liver. Data were analyzed using PROC MIXED in SAS as a replicated randomized complete block. Liver weights (actual, relative to BW, relative to HCW) were heavier (P ≤ 0.02) in OPEN. Rumen mass and kidney fat weight, both relative to BW, were also greater (P ≤ 0.04) in OPEN. On d 56 and at preslaughter, PREG cows had greater (P ≤ 0.04) BHBA, NEFA and urea concentrations and lower (P = 0.04) cholesterol concentration. Hepatic Na(+)/K+ ATPase abundance was greater (P = 0.04) in PREG cows. In rumen papillae, abundance of pAMPKα was increased (P = 0.006) in PREG cows. These data indicate that PREG cows may metabolize energy reserves and alter their metabolism to meet the energetic demands of the growing fetus.

Twenty-two nonlactating multiparous pregnant beef cows (639 ± 68 kg) were used to investigate the effect of dietary restriction on the abundance of selected proteins regulating cellular energy metabolism. Cows were fed at either 85% (n = 11; LOW) or 140% (n = 11; HIGH) of total NE requirements. The diet consisted of a haylage-based total mixed ration containing 20% wheat straw. Cows were slaughtered by block (predicted date of parturition), beginning 83 d after the initiation of dietary treatments and every week thereafter for 6 wk, such that each block was slaughtered at approximately 250 d of gestation. Tissue samples from liver, kidney, sternomandibularis muscle, ruminal papilli (ventral sac), pancreas, and small intestinal muscosa were collected at slaughter and snap frozen in liquid N2. Western blots were conducted to quantify abundance of proliferating cell nuclear antigen (PCNA), ATP synthase, ubiquitin, and Na/K+ ATPase for all tissues; PPARγ, PPARγ coactivator 1 α (PGC-1α), and 5´-adenosine monophosphate-activated protein kinase (AMPK) and the activated form phosphorylated-AMPK (pAMPK) for liver, muscle, and rumen; phosphoenolpyruvate carboxykinase (PEPCK) for liver and kidney; and uncoupling protein 2 (UCP2) for liver. Statistical analysis was conducted using Proc Mixed in SAS and included the fixed effects of dietary treatment, cow age, block, and the random effect of pen. Dietary treatments resulted in cows fed HIGH having greater (P ≤ 0.04) ADG and final BW than cows fed LOW. Abundance of ubiquitin in muscle was greater (P = 0.009) in cows fed LOW, and PCG-1 α in liver was greater (P = 0.03) in cows fed HIGH. Hepatic O2 consumption was greater in HIGH (P ≤ 0.04). Feed intake can influence the abundance of important metabolic proteins and suggest that protein degradation may increase in muscle from moderately nutrient restricted cows and that energy metabolism in liver increases in cows fed above NE requirements.

The DNA-binding activity and cellular distribution of the transcription factor NF-kappa B are regulated by the inhibitor protein I kappa B alpha. I kappa B alpha belongs to a family of proteins that contain multiple repeats of a 30- to 35-amino-acid sequence that was initially recognized in the erythrocyte protein ankyrin. Partial proteolysis has been used to study the domain structure of I kappa B alpha and to determine the sites at which it interacts with NF-kappa B. The data reveal a tripartite structure for I kappa B alpha in which a central, protease-resistant domain composed of five ankyrin repeats is flanked by an unstructured N-terminal extension and a compact, highly acidic C-terminal domain that is connected to the core of the protein by a flexible linker. Functional analysis of V8 cleavage products indicates that I kappa B alpha molecules lacking the N-terminal region can interact with and inhibit the DNA-binding activity of the p65 subunit of NF-kappa B, whereas I kappa B alpha molecules which lack both the N- and C-terminal regions are incapable of doing so. Protease cleavage of the N terminus of I kappa B alpha was unaffected by the presence of the p65 subunit of NF-kappa B, whereas bound p65 blocked cleavage of the flexible linker connecting the C-terminal domain to the ankyrin repeat-containing core of the protein. This linker region is highly conserved within the human, rat, pig, and chicken homologs of I kappa B alpha, and while it has been suggested that it represents a sixth ankyrin repeat, it is also likely that this is a flexible region of the protein that interacts with NF-kappa B.

Four crossbred steers (average BW = 478 ± 33 kg) were used in a 4 × 4 Latin square design to determine the effects of dietary concentration of dry corn distillers grains plus solubles (DDGS) in whole corn-based finishing diets on total tract digestion and nutrient balance and excretion. The DDGS were fed at 0% (control), 16.7%, 33.3%, and 50% of dietary DM. All diets contained 10% (DM basis) alfalfa/grass haylage and were formulated to meet or exceed the estimated requirements for CP. Steers were fed the experimental diets ad libitum for a 14-d adaptation period followed by a 5-d period for fecal and urine collection. Increasing concentration of DDGS in diets from 0 to 50% of DM linearly decreased (P0.05) total tract DM and starch digestibility (from 77.8 to 72.9%, and 89.2 to 81.5%, respectively). Daily N and P intakes linearly increased (P = 0.06 and P = 0.01, respectively) with increasing DDGS concentration. Fecal and urinary N, P, S, Mg, and K excretion linearly increased (P0.05) with increasing DDGS concentration; however, Se and Na excretion did not differ (P0.38) among treatments. Retention (g/d; intake minus urinary and fecal excretion) of N did not differ (P0.16) among treatments. Retention of P tended (P = 0.07) to linearly increase and retention of S (g/d) linearly increased (P = 0.004), with increasing DDGS concentration. There were no effects (P0.16) of dietary treatment on digestion and retention of Se, Mg, K, and Na. Plasma P and S concentrations increased (P = 0.03 and 0.01, respectively) with increasing DDGS concentration. These data indicate that feeding DDGS up to 50% of dietary DM in whole corn grain-based finishing diets does not have a negative effect on nutrient retention but decreases digestibility. Total excretion of N, P, Ca, Mg, S, and K increased as DDGS concentration increased.

In a previous study, we showed that the high level of protein tyrosine phosphorylation present in lymphomas containing an anaplastic lymphoma kinase (ALK) can be demonstrated in routinely processed paraffin tissue sections using immunolabelling techniques. In the present study we investigated whether oncogenic tyrosine kinase activation also occurs in other categories of lymphoma by staining 145 cases of lymphoma covering those tumours with a range of different subtypes including those with morphological similarity to ALK-positive anaplastic large cell lymphoma (ALCL). Twelve cases of the borderline malignant disorder lymphomatoid papulosis were also studied. Twenty seven of the 28 cases of ALK-positive ALCL showed the extensive cytoplasmic labelling for phosphotyrosine in the neoplastic cells. The remaining case containing moesin-ALK exhibited membrane-associated phosphotyrosine expression. There was no nuclear phosphotyrosine labelling in any of the ALK-positive ALCL, even though ALK was present within the cell nuclei in 23 of the tumours. Variable degrees of phosphotyrosine labelling, usually membrane-restricted, were observed in 7/40 cases of ALK-negative ALCL, 9/29 cases of diffuse large B-cell lymphoma, 3/6 cases of mediastinal B-cell lymphoma, 2/7 cases of Hodgkin's lymphoma, 3/6 cases of peripheral T-cell lymphomas unspecified, 4/6 cases of B-cell chronic lymphocytic leukaemia, 2/6 cases of follicular lymphomas and 2/12 cases of lymphomatoid papulosis studied. However none of these phosphotyrosine-positive cases showed the strong cytoplasmic labelling comparable to that seen in ALK-positive lymphoma. We conclude that activation of a tyrosine kinase is probably not a major oncogenic event in lymphomas other than ALK-positive ALCL.

The objective of this study was to characterise the regional variation in the barrier function of the gastrointestinal tract in Holstein calves using the flux rates of mannitol and inulin as permeability markers and tissue conductance (Gt) as an electrophysiological indicator of barrier function. Six Holstein steer calves (6 months of age) fed a common diet were used. Calves were killed by captive bolt stunning and pithing, and tissues were collected from the rumen, omasum, duodenum, jejunum, ileum, caecum, proximal colon, and distal colon. Tissues were carefully washed using a pre-heated (38.5°C) buffer solution (pH 7.4) saturated with oxygen and then transported to the laboratory. The mucosa was prepared by hand stripping and mounted between two halves of an Ussing chamber (n = 3/region with an exposed surface area of 3.14 cm2 for rumen and omasum and 1 cm2 for all other tissues). All tissues were incubated under short-circuit conditions and exposed to a similar buffer solution except for the energy source; rumen, omasum, caecum, and colon tissues were incubated with buffer containing short-chain fatty acids while tissues from the small intestine were bathed in buffer containing glucose. The Gt and the serosal-to-mucosal flux rates of 14C-inulin and 3H-mannitol were measured as indicators of barrier function. The serosal-to-mucosal flux rate of mannitol was greatest (P < 0.001) in the jejunum [104.8 nmol/(cm2 × h)] and least in the rumen and omasum [20.3 and 18.6 nmol/(cm2 × h), respectively]. In contrast, the serosal-to-mucosal flux rate of inulin was greatest (P < 0.001) in the omasum [158.6 nmol/(cm2 × h)] followed by the rumen [87.3 nmol/(cm2 × h)] with no differences among the other regions [18.7 – 62.0 nmol/(cm2 × h)]. The Gt was greatest (P < 0.001) in the jejunum (34.6 mS/cm2) and least for the rumen (3.67 mS/cm2) and omasum (3.23 mS/cm2). The Gt was correlated with both inulin and mannitol flux rates in duodenum, caecum and proximal colon (P < 0.05); whereas, no such correlations existed in jejunum, ileum and distal colon. The Gt was correlated with the mannitol flux rate but not the inulin flux rate in rumen and omasum. For all regions but the rumen and omasum there was a positive correlation between mannitol and inulin flux rates. These data indicate that the translocation of a large molecule (inulin) across the omasum and rumen is greatest despite having an apparently tight epithelium based on Gt and mannitol flux rate, while the jejunum appears to have greatest potential for paracellular permeability.

Assessment of the expression of antigens CD5, CD10 and CD23 can be of value in the differential diagnosis of small B-cell lymphoma. Correct subclassification is important since optimal treatment regimes differ between the subtypes. The aim of this study was to generate monoclonal antibodies recognizing these antigens in paraffin-embedded tissue and to assess their efficacy using a panel of cases of small B-cell lymphoma of various subtypes.For each antibody synthetic recombinant protein and conventional murine hybridoma technology was employed. Monoclonal antibodies effective in formalin-fixed, paraffin-embedded tissue were successfully generated, designated NCL-CD5-4C7, NCL-CD10-270 and NCL-CD23-1B12, respectively. A series of 58 cases of small B-cell lymphoma including examples of each subtype (lymphocytic, follicle centre cell, mantle cell, marginal zone and lymphoplasmacytoid) was assembled and immunostaining for the respective antigens carried out using the monoclonal antibodies produced. Our results indicate that the antibodies are specific for their respective antigens and give the predicted phenotypic profile in the small B-cell lymphoma subtypes.These novel monoclonal antibodies may be of value in routine diagnostic practice.

No-smoking policies are mandatory in U.S. hospitals. Consequently, smokers who are hospitalized must temporarily stop smoking. Nicotine-replacement therapy (NRT) could help hospitalized smokers relieve nicotine withdrawal symptoms, comply with no-smoking policies, and sustain tobacco abstinence after discharge. The extent of NRT use in the hospital setting is unknown. We describe the prevalence and patterns of NRT use in hospitalized smokers.Prospective observational study within a randomized smoking-intervention trial.Six hundred fifty adult smokers admitted to the medical and surgical services of a large urban teaching hospital that prohibits smoking in all indoor areas. Follow-up was at 6 months.Inpatient pharmacy records of nicotine patch or gum use.Only 34 of 650 smokers (5.2%) received NRT during their hospital stay, including only 9.6% of smokers who reported difficulty refraining from smoking while hospitalized and 9.0% of hospitalized smokers with nicotine withdrawal. NRT was more likely to be prescribed to patients with nicotine withdrawal (OR 2.23; 95% CI: 1.01, 4.90), a higher daily cigarette consumption (OR 1.04; 95% CI: 1.01, 1.06), and a longer hospitalization (OR 1.05; 95% CI: 1.00, 1.10). NRT use was independent of a patient's intention to quit smoking after discharge and was not associated with smoking cessation 1 and 6 months after discharge.NRT was rarely used in this hospital, even among those who could have benefited from it to treat nicotine-withdrawal symptoms. When NRT was used, relief of nicotine withdrawal, rather than assistance with smoking cessation, appeared to be the primary goal. Greater use of NRT could benefit the estimated 6.5 million smokers who are hospitalized annually by reducing nicotine withdrawal, encouraging smoking cessation, and ensuring compliance with hospital no-smoking policies.

The molecular mechanisms underlying Hodgkin's disease remain obscure, but it has been recognized that the neoplastic cells display high levels of constitutively active nuclear NF-kappaB. Here we demonstrate that although nuclear NF-kappaB is transcriptionally active, the Hodgkin cells fail to activate NF-kappaB dependent transcription in response to CD40 ligand. In three Hodgkin cell lines examined each had abnormalities in expression of IkappaBalpha which could account for the deregulated NF-kappaB. Although all three cell lines had greater than normal levels of IkappaBalpha mRNA no IkappaBalpha protein could be detected in the KM-H2 cells, while the L428 cell line contains a C-terminally truncated IkappaBalpha species that fails to associate with NF-kappaB. The HDLM-2 cell line contains a more slowly migrating form of IkappaBalpha that can associate with NF-kappaB, but increasing the level of this protein within the cell fails to inhibit nuclear NF-kappaB. Addition of recombinant IkappaBalpha to nuclear extracts from all three cell lines resulted in complete inhibition of NF-kappaB DNA binding activity and introduction of a plasmid expressing IkappaBalpha into the cells inhibited the transcriptional activity of an NF-kappaB dependent reporter plasmid. Thus the constitutive expression of NF-kappaB in Hodgkin cells is a direct consequence of the abnormal expression of IkappaBalpha rather than changes in NF-kappaB that render it refractory to inhibition by IkappaB proteins. These changes could, at least in part, account for the characteristic activated phenotype of Hodgkin cells and their pattern of cytokine secretion, which determine the pathological appearance and clinical manifestations of Hodgkin's disease.

Hospitalization may be an opportune time to change smoking behavior because it requires smokers to abstain from tobacco at the same time that illness can motivate them to quit. A hospital-based intervention may promote smoking cessation after discharge.We tested the efficacy of a brief bedside smoking counseling program in a randomized controlled trial at Massachusetts General Hospital, Boston. The 650 adult smokers admitted to the medical and surgical services were randomly assigned to receive usual care or a hospital-based smoking intervention consisting of (1) a 15-minute bedside counseling session, (2) written self-help material, (3) a chart prompt reminding physicians to advise smoking cessation, and (4) up to 3 weekly counseling telephone calls after discharge. Smoking status was assessed 1 and 6 months after hospital discharge by self-report and validated at 6 months by measurement of saliva cotinine levels.One month after discharge, more intervention than control patients were not smoking (28.9% vs 18.9%; P=.003). The effect persisted after multiple logistic regression analyses adjusted for baseline group differences, length of stay, postdischarge smoking treatment, and hospital readmission (adjusted odds ratio, 2.19; 95% confidence interval, 1.34-3.57). At 6 months, the intervention and control groups did not differ in smoking cessation rate by self-report (17.3% vs 14.0%; P=.26) or biochemical validation (8.1% vs 8.7%; P=.72), although the program appeared to be effective among the 167 patients who had not previously tried to quit smoking (15.3% vs 3.7%; P=.01).A low-intensity, hospital-based smoking cessation program increased smoking cessation rates for 1 month after discharge but did not lead to long-term tobacco abstinence. A longer period of telephone contact after discharge might build on this initial success to produce permanent smoking cessation among hospitalized smokers.

Many physician group practices--particularly practices that have been acquired by hospitals and integrated delivery systems--are experiencing expense increases and productivity decreases. Physician group practices can take steps to reverse these unfavorable trends by carefully reviewing and benchmarking practice costs related to physician compensation plans, support staff salaries and benefits, occupancy costs, clinical supply costs, and malpractice insurance. Group practices also can improve cost management and resource utilization by creating an operating budget based on historical expenditures and anticipated revenues and by comparing it with peer benchmarks.

The t(2;5)(p23;q35) translocation, associated with anaplastic large-cell lymphoma (ALCL), results in the production of the nucleolar protein nucleophosmin-anaplastic lymphoma kinase (NPM-ALK) protein. This report describes an immunocytochemical study of the distribution of ALK and NPM-ALK proteins using a new monoclonal antibody, ALK1, that recognizes a formalin resistant epitope in both the 80-kD NPM-ALK chimeric and the 200-kD normal human ALK proteins. Cytoplasmic and nuclear labeling was seen in the t(2;5)+ SU-DHL-1 and Karpas 299 cell lines. Normal ALK protein expression was restricted to the central nervous system (in scattered neurons, glial cells, and endothelial cells). Two hundred and thirty-nine cases of lymphoma and 80 nonhematopoietic tumors were immunostained. Antibody ALK1 labeled 53.4% (39 of 73 cases) of CD30+ ALCL. A case of ALCL with a t(1;2) translocation was ALK1+. Three cases of CD30- ALCL with prominent nucleoli showed a unique pattern of coarse granular cytoplasmic labeling. All other tumors, including Hodgkin's disease and lymphomatoid papulosis, were ALK1-. These results indicate that reliable immunostaining of routine biopsy material for NPM-ALK and ALK proteins is feasible. Such analysis is of diagnostic importance, especially because t(2;5)+ ALCL cases have a good prognosis with appropriate treatment.

The DNA-binding activity and cellular distribution of the transcription factor NF-kappa B are regulated by the inhibitor protein I kappa B alpha. I kappa B alpha belongs to a family of proteins that contain multiple repeats of a 30- to 35-amino-acid sequence that was initially recognized in the erythrocyte protein ankyrin. Partial proteolysis has been used to study the domain structure of I kappa B alpha and to determine the sites at which it interacts with NF-kappa B. The data reveal a tripartite structure for I kappa B alpha in which a central, protease-resistant domain composed of five ankyrin repeats is flanked by an unstructured N-terminal extension and a compact, highly acidic C-terminal domain that is connected to the core of the protein by a flexible linker. Functional analysis of V8 cleavage products indicates that I kappa B alpha molecules lacking the N-terminal region can interact with and inhibit the DNA-binding activity of the p65 subunit of NF-kappa B, whereas I kappa B alpha molecules which lack both the N- and C-terminal regions are incapable of doing so. Protease cleavage of the N terminus of I kappa B alpha was unaffected by the presence of the p65 subunit of NF-kappa B, whereas bound p65 blocked cleavage of the flexible linker connecting the C-terminal domain to the ankyrin repeat-containing core of the protein. This linker region is highly conserved within the human, rat, pig, and chicken homologs of I kappa B alpha, and while it has been suggested that it represents a sixth ankyrin repeat, it is also likely that this is a flexible region of the protein that interacts with NF-kappa B.

Chronic inflammatory cells are a recognized component of atherosclerotic plaques at all stages of development. As adhesion molecules play a fundamental role in inflammatory processes, we have carried out an immunohistochemical investigation of the distribution of endothelial leucocyte adhesion molecule-1 (ELAM-1)*, intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in human atherosclerotic lesions. Autopsy specimens from abdominal aorta and coronary arteries were obtained from 21 cases within 24 h of death. ELAM-1 and ICAM-1 were consistently expressed by the entire intimal endothelium of normal coronary arteries and also by the intimal endothelium overlying aortic fatty streaks. Both coronary artery and aortic lesions showed strong staining for ICAM-1 on and around macrophages. VCAM-1 was not detected on intimal endothelial cells, but strong staining of adventitial lymphoid aggregates for this molecule was seen. This work suggests a role for ELAM-1 and ICAM-1 in mononuclear cell recruitment during atherogenesis.

CD 3 antigen expression was studied in a series of 98 T-cell lymphomas, using polyclonal antibodies which recognize this molecule in routinely processed, paraffin-embedded, tissue. We identified 40 cases in which CD3 was present on only a proportion of the neoplastic cells. This phenomenon of heterogeneous CD3 expression was commonest in pleomorphic T-cell lymphomas (22/42 cases) and in CD30 (Ki-1)-positive lymphomas (5/11 cases), and was less frequently observed in mycosis fungoides (4/18 cases) and not seen in T-cell lymphoblastic lymphoma (0/9 cases). CD3 expression was often related to cell morphology, with CD3 antigen being present on the smaller neoplastic cells but absent from the larger ones. The diagnostic significance of these observations is that, on occasion, it may be possible to diagnose a lymphoma as being of T-cell origin in paraffin sections by demonstrating a minor subpopulation of CD3-positive neoplastic cells.

This paper describes experiments designed to test the hypothesis that DNA sequences upstream from the mouse rRNA promoter are transcribed in vivo or in vitro. Plasmid pB28 contains a SalI restriction fragment that extends from -169 to -1,894 base pairs, with respect to the origin of transcription of pre-rRNA. Labeled RNA synthesized in intact cells does not hybridize to this region. Neither S1 nuclease mapping nor RNA dot blot hybridization revealed the presence of sequences complementary to this region. Transcriptional studies carried out in vitro indicated that this region is not transcribed under conditions that are optimal for utilization of the authentic rRNA promoter. Moreover, this region does not appear to form stable transcription complexes with RNA polymerase I transcription components. These data indicate that the mouse rDNA repeating unit differs from those of Xenopus spp. and Drosophila melanogaster in that reduplicated RNA polymerase I promoters are not found in the mouse rDNA spacer region.

A small clinical trial was conducted to compare a modified subcutaneous injection technique with the standard subcutaneous method. The data in this study do not strongly support the use of either technique. However, the modified subcutaneous method may be preferable in that fewer injection-site hematomas formed. Further research with a larger population is indicated before either method can be recommended over the other.

The active uptake of 5-hydroxytryptamine (5-HT) by platelets from migraine patients was measured and the results compared with 5-HT uptake of platelets from normal subjects. No significant differences in platelet 5-HT uptake were found between migraine patients and control subjects. A significant correlation was found between the length of time since the patients last migraine attack and Vmax (maximal rate of 5-HT transport). Patients who had a headache within five days prior to the test had significantly lower values of Vmax than patients without recent headaches. The implications and possible causes of this reduction in platelet 5-HT transport are discussed.