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The article discusses the physical characters of cashmere and the decrease of percentage in goat fleeces in Great Britain. Cashmere is the undercoat of the domestic goats in Asia and one of the finest and softest animal fibers in the textile industry. The fine undercoat of the primitive breeds is intermixed with the coarser outer coat to form a fleece which is known as the mixed-wool type. On the other hand, the improved breeds such as the Merino reached its highest stage of development, making up the entire fleece.

Clenbuterol was intended as a treatment for respiratory diseases in horses, but has been used in multiple species, including humans, for its repartitioning of fat to lean effects (free fatty acids are released from adipose tissue to be used by tissues of higher priority). In the horse industry clenbuterol application is restricted to the treatment of chronic obstructive pulmonary disease and reactive airway disease (heaves). Negative effects of clenbuterol exposure include a decrease in maximum oxygen intake and increased muscle fatigue upon exercise. As a result of these and other negative effects, clenbuterol remains strictly controlled by the US Food and Drug Administration. [ABSTRACT FROM AUTHOR]

Comparative, dose-dependent analysis of interactions between small molecule drugs and their targets, as well as off-target interactions, in complex proteomes is crucial for selecting optimal drug candidates. The affinity of small molecules for targeted proteins is largely dictated by interactions between amino acid side chains and these drugs. Thus, studying drug-protein interactions at an amino acid resolution provides a comprehensive understanding of the drug selectivity and efficacy. In this study, we further refined the site-specific activity-based protein profiling strategy (ABPP), PhosID-ABPP, on a timsTOF HT mass spectrometer. This refinement enables dual dose-dependent competition of inhibitors within a single cellular proteome. Here, a comparative analysis of two activity-based probes (ABPs), developed to selectively target the epidermal growth factor receptor (EGFR), namely, PF-06672131 (PF131) and PF-6422899 (PF899), facilitated the simultaneous identification of ABP-specific binding sites at a proteome-wide scale within a cellular proteome. Dose-dependent probe-binding preferences for proteinaceous cysteines, even at low nanomolar ABP concentrations, could be revealed. Notably, in addition to the intrinsic affinity of the electrophilic probes for specific sites in targeted proteins, the observed labeling intensity is influenced by several other factors. These include the efficiency of cellular uptake, the stability of the probes, and their intracellular distribution. While both ABPs showed comparable labeling efficiency for EGFR, PF131 had a broader off-target reactivity profile. In contrast, PF899 exhibited a higher labeling efficiency for the ERBB2 receptor and bound to catalytic cysteines in several other enzymes, which is likely to disrupt their catalytic activity. Notably, PF131 effectively labeled ADP/ATP translocase proteins at a concentration of just 1 nm, and we found this affected ATP transport. Analysis of the effect of PF131 and its parent inhibitor Afatinib on murine translocase SLC25A4 (ANT1)-mediated ATP transport strongly indicated that PF131 (10 μM) partially blocked ATP transport. Afatinib was less efficient at inhibiting ATP transport by SLC25A4 than PF131, and the reduction of ATP transport by Afatinib was not significant. Follow-up analysis is required to evaluate the affinity of these inhibitors for ADP/ATP translocase SLC25A4 in more detail. Additionally, the analysis of different binding sites within the EGF receptor and the voltage-dependent anion channel 2 revealed secondary binding sites of both probes and provided insights into the binding poses of inhibitors on these proteins. Insights from the PhosID-ABPP analysis of these two ABPs serve as a valuable resource for understanding drug on- and off-target engagement in a dose- and site-specific manner.

Most drug molecules target proteins. Identification of the exact drug binding sites on these proteins is essential to understand and predict how drugs affect protein structure and function. To address this challenge, we developed a strategy that uses immobilized metal-affinity chromatography-enrichable phosphonate affinity tags, for efficient and selective enrichment of peptides bound to an activity-based probe, enabling the identification of the exact drug binding site. As a proof of concept, using this approach, termed PhosID-ABPP (activity-based protein profiling), over 500 unique binding sites were reproducibly identified of an alkynylated afatinib derivative (PF-06672131). As PhosID-ABPP is compatible with intact cell inhibitor treatment, we investigated the quantitative differences in approachable binding sites in intact cells and in lysates of the same cell line and observed and quantified substantial differences. Moreover, an alternative protease digestion approach was used to capture the previously reported binding site on the epidermal growth factor receptor, which turned out to remain elusive when using solely trypsin as protease. Overall, we find that PhosID-ABPP is highly complementary to biotin-based enrichment strategies in ABPP studies, with PhosID-ABPP providing the advantage of direct activity-based probe interaction site identification., Competing Interests: Conflict of interest The authors declare no competing interest., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

Tight regulation of protein translation drives the proteome to undergo changes under influence of extracellular or intracellular signals. Despite mass spectrometry-based proteomics being an excellent method to study differences in protein abundance in complex proteomes, analyzing minute or rapid changes in protein synthesis and abundance remains challenging. Therefore, several dedicated techniques to directly detect and quantify newly synthesized proteins have been developed, notably puromycin-based, bio-orthogonal noncanonical amino acid tagging-based, and stable isotope labeling by amino acids in cell culture-based methods, combined with mass spectrometry. These techniques have enabled the investigation of perturbations, stress, or stimuli on protein synthesis. Improvements of these methods are still necessary to overcome various remaining limitations. Recent improvements include enhanced enrichment approaches and combinations with various stable isotope labeling techniques, which allow for more accurate analysis and comparison between conditions on shorter timeframes and in more challenging systems. Here, we aim to review the current state in this field., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: Delirium is a serious neuropsychiatric syndrome, which requires timely treatment. However, it is easily missed, especially in older patients with premorbid cognitive disorders., Objectives: The aim of this study is to investigate the prevalence and risk factors of delirium in older outpatients with and without dementia., Method: We assessed 444 patients referred to the memory clinic of a psychiatric hospital between March 2013 and March 2014. Demographic information, medical history, impairments in daily living activities and referral information were registered. Patients underwent a psychiatric examination using the Delirium Rating Scale-Revised-98 and cognitive tests, a physical examination and laboratory tests. We recorded medication use and changes before and after the onset of symptoms., Results: Among the 444 outpatients, 85 had probable delirium (prevalence of 19%), and 10 had subsyndromal delirium (2%). The most common triggers were infection (42%), drug-intoxication or withdrawal (22%), and metabolic/endocrine disturbance (12%). Age (OR 1.07, 95% CI 1.02-1.11) and prior delirium (OR 3.34, 95% CI 1.28-8.69) were independent non-modifiable factors associated with an increased risk of delirium. The only independent modifiable risk factor was infection (OR 17.31, 95% CI 8.44-35.49)., Conclusions: A delirium was detected in one of five patients referred for dementia screening. Most patients could be treated at home. Age and prior delirium were predictive of an increased risk of delirium., (© 2020 The Authors. International Journal of Geriatric Psychiatry published by John Wiley & Sons Ltd.)

Chlamydial-induced cystitis in the koala (Phascolarctos cinereus) is currently treated by antibiotics. However, while reducing the chlamydial load, this treatment can also lead to gastrointestinal complications and death. Development of alternative treatments, such as a therapeutic chlamydial vaccine, are hindered by the lack of detailed understanding of the innate immune response to chlamydial clearance and disease regression during antibiotic treatment. Through clinical, microbiological and transcriptomic approaches, disease regression, bacterial clearance and innate immune responses were mapped in koalas with signs of chlamydial-induced cystitis while receiving anti-chlamydial antibiotics. Significant reduction in the signs of cystitis were observed during and post antibiotic treatment. This was observed as a thinning of the bladder wall and complete reversal of urinary incontinence. Transcriptomic analysis before treatment, at the end of treatment and prior to release identified significant down-regulation of specific genes involved in 21 biological pathways. Of these, the chemokine receptor signalling and NOD-like receptor signalling pathways where identified as important markers of inflammation. Specific genes within these pathways (NCF1 and NOX2) were significantly down-regulated, suggesting a decrease in reactive oxygen species production. Through the monitoring of specific clinical and transcriptomic markers, these findings allow detailed profiling of the clinical response to therapeutic vaccination in koalas with current signs of disease. This also adds to our understanding of innate immune responses to chlamydial infections and indicates that chlamydial-induced cystitis in the koala is linked to the regulation of reactive oxygen pathways., Competing Interests: The authors have declared that no competing interests exist.

Tuberculosis (TB) remains a major global public health problem that has become a crisis fuelled by HIV and the increasing occurrence of antimicrobial resistance. What has been termed the biosocial nature of TB challenges effective control of the disease. Yet, biosocial interactions involved in the persistence of TB in diverse settings are difficult to systematically account for. The recently developed framework of syndemics provides a way to capture how complex health problems result from the interactions between diseases such as HIV and TB, and harmful social conditions such as unemployment, malnutrition and substance abuse. This article advances the syndemics scholarship by examining health conditions that cluster together with TB in the Russian Federation, by eliciting a set of social processes that precipitate this clustering and exacerbate health outcomes, and by analysing interactions between these health conditions and social processes. To provide an account of this complexity, the article takes a qualitative approach and draws on the perspectives and experiences of people with TB. The results demonstrate emergence of a syndemic of stress, substance abuse, TB and HIV that is sustained by poverty, occupational insecurity, marginalization and isolation. Frictions between the narrow focus of the health care system on TB and the wider syndemic processes in which the lives of many persons with TB are embedded, contribute to poorer health outcomes and increase the risks of developing drug resistance. Finally, the article argues that the large-scale and impersonal forces become embodied as individual pathology through the crucial interface of the ways in which persons experience and make sense of these forces and pathologies. Qualitative research is needed for the adequate analysis of this biosocial complexity in order to provide a solid basis for responses to TB-centred syndemics in various settings.

Adipose tissue is derived from numerous sources, and in recent years this tissue has been shown to provide numerous cells from what seemingly was a population of homogeneous adipocytes. Considering the types of cells that adipose tissue-derived cells may form, these cells may be useful in a variety of clinical and scientific applications. The focus of this paper is to reflect on this area of research and to provide a list of potential (future) research areas.

As research funding becomes more competitive, it will be imperative for researchers to break the mentality of a single laboratory/single research focus and develop an interdisciplinary research team aimed at addressing real world challenges. Members of this team may be at the same institution, may be found regionally, or may be international. However, all must share the same passion for a topic that is bigger than any individual's research focus. Moreover, special consideration should be given to the professional development issues of junior faculty participating in interdisciplinary research teams. While participation may be "humbling" at times, the sheer volume of research progress that may be achieved through interdisciplinary collaboration, even in light of a short supply of grant dollars, is remarkable., (Copyright 2009 Elsevier Inc. All rights reserved.)

Beta-adrenergic agonists (beta-AA) enhance protein accretion in skeletal muscles. This stimulation is characterized by increased protein synthesis, increased expression of myofibrillar protein genes and a depression in protein degradation in animals, and increased proliferation and DNA synthesis in muscle cells in vitro. The mechanism or signal path in muscle whereby beta-AA would elicit these physiological effects upon binding to the G protein-coupled beta-adrenergic receptor (beta-AR) is unclear. C2C12 myoblasts were used to determine beta-AR ligand binding characteristics, cyclic AMP synthesis in response to isoproterenol (ISO) stimulation, and effects of ISO on DNA synthesis, mitogen activated protein kinase (MAPK), and fibronectin (FN) gene expression. Results showed that C2C12 cells possess beta-AR which are specific, saturable, and of high affinity (Kd = 0.2 nM). Forskolin and ISO stimulated cAMP production by = 20-fold (P<0.001) and 17-fold (P<0.001), respectively. ISO and the cAMP analog, 8-bromo-cAMP (8-BC) stimulated DNA synthesis in proliferating cells by 150% (P<0.05) and 200% (P<0.01), respectively, without modulating MAPK activity, whereas addition of fetal bovine serum to culture resulted in a 500% increase (P<0.01) in DNA synthesis and MAPK activation. DNA synthesis in C2C12 cells treated with ISO, 8-BC, or FBS was abolished in the presence of 25 microM PD098059, an MAPK-kinase inhibitor, suggesting that an MAPK-dependent pathway is likely involved in C2C12 proliferation. During cAMP elevating agent stimulation, basal MAPK activity may be sufficient, in the presence of other putative signaling molecules, to support proliferation in these cells. ISO or 8-BC treatment increased FN mRNA by three- and seven-fold, respectively, in growing C2C12 cells implying a connection between increased DNA synthesis and FN gene expression.

Forty-one Holstein cows were injected with 0, 5, or 14 mg/d of bST for the last 46 +/- 6 d before parturition. Compared with data for controls, the 5- and 14-mg doses of bST increased apparent protein synthesis about 16% before parturition. Exogenous bST before parturition increased apparent protein degradation 30% during wk 1 after parturition. During wk 1 of lactation, 14 mg of bST also increased milk protein yield 33%. No treatment differences were present in concentration of serum NEFA, body condition score, or thickness of subcutaneous fat. Therefore, administration of bST before parturition did not alter metabolism of subcutaneous fat. Prepartum treatment with 5 and 14 mg of bST increased and maintained serum somatotropin at 6.5 and 22.7 ng/ml, respectively, compared with 1.6 ng/ml in controls. Concentrations of serum IGF-I were initially increased but were not maintained as parturition approached. On d -23, IGF binding protein 3 was increased 65% but was not different among groups by d -7. For groups administered the 5 and 14 mg/d of bST, IGF binding protein 2 was decreased 40%. Administration of bST before parturition increased protein reserves and stimulated milk protein yield for 1 wk but did not alter metabolism of subcutaneous fat. Furthermore, energy balance appeared to be a major regulator of concentrations of IGF binding protein 3 and responsiveness of IGF-I to exogenous somatotropin before parturition.

Sixty crossbred barrows were used to study the effect of ractopamine (a phenethanolamine/beta-adrenergic agonist) treatment and its withdrawal on muscle growth and on the relative abundance of skeletal muscle alpha-actin (sk-alpha-actin) mRNA and of liver and longissimus muscle IGF-I mRNA at 4 wk. Ractopamine was fed (20 ppm) for periods of 2, 4, and 6 wk (six pigs per group). Additional pigs (four per group) were fed ractopamine (20 ppm) for 6 wk and then slaughtered 1, 3, and 7 d after withdrawal of ractopamine. Ractopamine increased (P < .05) longisimus muscle weight and protein content, although protein concentrations were not different. The increased muscle weight and protein content attained by feeding ractopamine for 6 wk was retained when ractopamine was withdrawn. The RNA and DNA concentrations did not change, whereas total DNA and RNA content per muscle was 18 and 26.7% greater, respectively, in ractopamine-treated pigs at 4 wk, but there were no differences at 2 or 6 wk or among the withdrawal groups. The relative abundance of sk-alpha-actin mRNA in the longissimus muscle was 41 and 62% greater (P < .05) in treated animals at 2 and 4 wk but was similar to that in controls at 6 wk and during the withdrawal period. The relative abundance of IGF-I mRNA in liver and longissimus muscle was not altered with ractopamine treatment for 4 wk. These results indicate that the ractopamine-enhanced muscle growth may result from increased myofibrillar gene expression at the pretranslational level, which is maximal with short-term treatment of ractopamine.(ABSTRACT TRUNCATED AT 250 WORDS)

1. Using epinephrine plus propranolol we demonstrated alpha-2 adrenergic receptor (alpha 2AR) activity (49% inhibition of theophylline stimulated lipolysis) in adipocytes of adult intact male pigs (61 kg body wt and 97 microns adipocyte diameter). 2. Dose titration with an alpha 2AR antagonist (yohimbine) confirmed alpha 2AR associated activity. 3. No alpha 2AR activity was observed in younger male or castrated male pigs. 4. The inhibitory action on lipolysis via the alpha 2AR in pigs is dependent on androgen status and adipocyte size or age.

The stable adipogenic cell line TA1 was investigated as a potential in vitro system to examine effects of beta-adrenergic agonists on lipid metabolism at the cellular level. Initial experiments were conducted to establish whether dexamethasone, indomethacin, or both in combination induce rapid differentiation of TA1 preadipocytes to adipocytes. Based on activity of fatty acid synthase, dexamethasone and indomethacin, individually and in combination, were observed to induce differentiation in TA1 cells at different rates (dexamethasone/indomethacin greater than indomethacin greater than dexamethasone). Dexamethasone/indomethacin induced complete differentiation in TA1 cells 4 days after confluence, as indicated by increased activity of fatty acid synthase, glycerol-3-phosphate dehydrogenase, and malic enzyme. Finally, mature TA1 adipocytes were treated with various concentrations of isoproterenol and ractopamine to determine the responsiveness of TA1 adipocytes to a beta-adrenergic challenge. Glycerol release was increased and fatty acid synthase activity was decreased in a dose-dependent manner for both isoproterenol and ractopamine. These results indicate that fully differentiated TA1 adipocytes may be useful to study direct cellular effects of lipolytic and lipogenic agents on lipid metabolism.

Skeletal muscle protein degradation, measured by urinary N tau-methylhistidine excretion, and circulating concentrations of growth hormone (GH), insulin (INS), and cortisol (CT) were monitored in steers before and after implantation with estradiol-17 beta (E2; 24 mg) and trenbolone acetate (TBA; 300 mg). Yearling crossbred steers (n = 43) were randomly assigned to four treatment groups in a 2 x 2 factorial arrangement: nonimplanted controls (C); TBA; E2; and TBA plus E2 (TBA+E2). A subgroup (Block 1) of 16 steers was bled on d -12, 31, and 72 after implanting. Deposition of skeletal muscle protein was markedly increased (P less than .001) by E2 and TBA+E2 treatment. This response occurred mainly within the first 40 d after implantation and declined (P less than .001) in concert with decreasing (P less than .01) concentration of serum E2. Anabolic steroid treatment did not affect the rate of skeletal muscle protein breakdown. There was no apparent relationship between reduced serum CT concentration (linear effect; P less than .01) in TBA-treated steers and skeletal muscle protein degradation rate. Blood concentration and pulse activity of INS were not affected by anabolic steroid administration. Both TBA- and TBA+E2-implanted steers displayed a linear decrease (P less than .05) in serum GH concentration over time, which was similar to C. Lowered mean GH concentration resulted from a reduction (TBA main effect; P less than .05) in pulse amplitude of GH. Unlike TBA, TBA+E2, and C, only E2 maintained serum GH concentrations over time. Although increased muscle protein deposition was evident in TBA+E2-treated steers, an obvious causal relationship between this response and circulating GH, INS, and CT was not revealed. These results do not support the concept that combined androgenic agent and estrogen administration effectively reduce bovine muscle protein degradation by static modulation of circulating endogenous anabolic and antianabolic hormones.

1. Two populations of beta-adrenergic receptor (beta AR) subtypes and their proportions were characterized in adipocytes isolated from subcutaneous adipose tissue of castrated male crossbred pigs (60-85 kg). 2. Specific binding of the radioligand 125I-iodopindolol (IPIN) to crude plasma membranes (70-90% of total binding) reached equilibrium conditions in 30 min (38 degrees C), was tissue concentration-dependent, stereospecific and saturable (bmax = 168 +/- 5.8 fmol/mg protein). 3. Displacement curves by ICI 89,406 were best-fit by a two site model (P less than 0.01) that indicated the presence of two receptor populations and selectivity of IPIN for the beta 2AR subtype. 4. Forty-five percent of the receptors had a high affinity for ICI 89,406, Ki = 2.27 +/- 0.68 nM and were classified as beta 1AR.

We report the second case of a primary aortoenteric fistula resulting from septic aortitis with a contained aortic leak into the retroperitoneum and finally erosion into the duodenum. An emergency laparotomy revealed a fistula between the third part of the duodenum and a decompressed sac (false aneurysm) arising from a nonaneurysmal, grossly infected pararenal aorta. The purpose of this report is to present this rare case in detail and to review primary aortoenteric fistulas reported in the English language literature. Most fistulas form in association with an abdominal aortic aneurysm and rarely are due to infection. Only 6% of patients presented with the classic triad of abdominal pain, a palpable mass, and gastrointestinal bleeding. Although 29% of patients presented with massive hemorrhage, adequate time usually existed for surgical treatment of these complications. A patient with ill-defined abdominal pain and fever who suddenly develops a palpable abdominal mass should have an emergency ultrasound or CT scan to exclude the possibility of an infected aortic aneurysm or a contained rupture of an infected nonaneurysmal aorta. If the symptoms are associated with bleeding and the patient is hemodynamically stable, emergent endoscopy should also be performed. If a primary aortoenteric fistula or an aortic pseudoaneurysm is confirmed, emergent surgery should be undertaken to avoid rupture into the bowel or retroperitoneum.

Excess fat in meat products has been identified as a dietary problem by public health officials. The meat animal industry has responded during the last 25 years to concerns about excess fat intake from animal products by implementing strategies to depress fat deposition and increase lean (protein) tissue gain in meat animals. The most successful strategy to date is the use of large, late-maturing animals for meat production. At desired market weights, these animals are much leaner than smaller, early-maturing animals. In addition, exogenous agents such as anabolic steroids (FDA approved for cattle) have been used to increase lean gain and depress fat deposition in cattle. Growth hormone (GH) and beta-adrenergic agonists (beta AA) are not yet approved by the FDA, but if/when approved would also markedly increase lean gain and depress fat deposition. Both GH and beta AA are called partitioning agents because they partition nutrients and energy toward lean (protein) accretion and dramatically lower fat deposition. Contingent on approval by the FDA and subsequent adoption of partitioning agents by the animal industry would result in meat products containing less and 30% of total calories from fat.

Two experiments were conducted to ascertain lysine required for maintenance and milk production in lactating dairy cows. Multiparous Holstein cows fitted with abomasal cannulas were utilized in a replicated 3 x 3 extra-period Latin square design and infused with 0, 45, or 90 g of L-lysine-HCl daily (Experiment 1). In Experiment 2, 12 cows were utilized in a 5 x 5 Latin square design (with 2 replacement cows) and infused with 0, 22.5, 45, 90, and 180 g of L-lysine-HCl daily. Cows were housed in comfort stalls, milked at 0600 and 1700 h, exposed to a 16:8 h light:darkness cycle, and fed for ad libitum intake a 15.7% CP diet formulated to contain approximately 75% of dietary protein from corn-based feed ingredients. Milk yield was not affected in Experiment 1, but milk production increased linearly with lysine infusion level in Experiment 2. A linear response in daily yield of milk protein to lysine infusion was observed in both experiments. As lysine infusion increased, coccygeal plasma lysine concentrations tended to increase in Experiment 1, but in Experiment 2 free lysine increased linearly and quadratically in coccygeal plasma and increased linearly in plasma from the subcutaneous abdominal vein. The quadratic response in plasma free lysine (Experiment 2) suggested that lysine was the limiting AA for milk production from the composite protein flow to the small intestine. Using break-point analysis of plasma free lysine, it was estimated that the additional amount of abomasal lysine required to satisfy requirements was 64 g/d in cows producing about 30 kg of milk daily. Although additional lysine above microbial and undegraded intake protein lysine flow stimulated milk protein production, conversion efficiency to milk protein lysine was low.

Thirty patients with Stage III/IV cancer and thromboembolic complications between 1987-89 were reviewed. Twelve patients had a deep venous thrombosis proximal to the calf diagnosed by duplex scanning or contrast venography, 15 patients had a pulmonary embolism diagnosed by a high-probability pulmonary ventilation/perfusion scan or arteriogram, and three patients had both deep vein thrombosis and pulmonary embolism. Patients were treated primarily with anticoagulation (Group A = 20 patients) or a Greenfield filter (Group B = 10 patients). Seventy-five percent (15/20) of the Group A patients developed 19 bleeding or thrombosis-related complications: major bleeding (7), recurrent deep venous thrombosis/pulmonary embolism (4), inability to attain consistent therapeutic anticoagulation levels (3), heparin-induced thrombocytopenia (3), or progression of deep vein thrombosis (2). A Greenfield filter was eventually placed in 10 (50%) of the Group A patients without complications. Thirty percent (3/10) of the Group B patients developed progression of deep vein thrombosis that required anticoagulation. One other Group B patient died due to a guidewire-induced arrhythmia. Although patients with advanced cancers and venous thromboembolic disease have a high complication rate with either treatment, initial treatment with a Greenfield filter appears more definitive. Anticoagulation should be reserved for patients with progressive, symptomatic deep vein thromboses after placement of a filter.

The ability of the phenethanolamine (beta-adrenergic agonist) ractopamine to stimulate cellular protein accretion and protein synthesis in cultured muscle cells was evaluated. ELC5 myoblasts (a subclone of rat L6 cells) were proliferated in culture (Dulbecco's Modified Eagle Medium plus 10% fetal bovine serum at 37 degrees C) to confluency and then allowed to differentiate to form myotubes. Myotubes were then further incubated in the presence of 10(-9), 10(-8), 10(-7), 10(-6) or 10(-5) mol/L ractopamine. A significant (p less than 0.05) response in cellular protein accretion was observed for the 10(-6) and 10(-5) concentrations when compared to 10(-8) and 10(-9) mol/L ractopamine. Ractopamine at 0 and 10(-6) mol/L was used to examine the effect of the beta agonist on [35S]methionine incorporation (protein synthesis) into total cellular protein, 43-kDa proteins and myosin heavy-chain (200 kDa) protein. Protein synthesis in response to beta agonist treatment was measured at 4, 24, 48, 72 and 96 h after ractopamine addition to the ELC5 myotubes in culture. Ractopamine (10(-6) mol/L) increased [35S]methionine incorporation (apparent protein synthesis) at 24 h (p less than 0.01), 48 h (p less than 0.05), 72 h (p less than 0.01) and 96 h (p less than 0.05) in cultured ELC5 muscle cells. Ractopamine also increased apparent protein synthesis rate of the 43-kDa proteins (p less than 0.05) and myosin heavy-chain protein (200 kDa) (p less than 0.05). These results indicate that ractopamine-enhanced ELC5 myotube protein accretion is mediated, at least in part, by stimulating cellular protein synthesis.

Six lactating Holstein cows, fitted with T-type cannulas in the proximal duodenum, were used in a replicated 3 x 3 Latin square design to determine influence of supplemental protein on amino acid profiles of duodenal chyme and plasma. Protein sources were blood meal, corn gluten meal, and cottonseed meal, which furnished approximately 46% of the total protein in corn-grain corn silage diets. Markers were 15N to estimate rumen bacteria and chromic oxide to estimate nutrient flow. Dry matter intake was lowest on blood meal. Duodenal flow of N exceeded N intake 23% on blood meal and corn gluten meal. Percentages of organic matter and protein digested in the rumen were 56.5, 41.8; 61.2, 53.4; and 50.6, 56.2 for the respective diets. Variation in patterns of amino acids flowing to the duodenum, but not in coccygeal blood, closely reflected dietary differences with six of eight essential amino acids highest for the same treatment in both diet and duodenal chyme. Essential amino acids in least abundance for milk production, measured by mammary extraction coefficients, differed among diets. We conclude that supplemental protein source influences greatly the quantity and pattern of amino acids available for digestion in lactating dairy cows.

Ractopamine [1-(4-hydroxyphenyl-2-(1-methyl-3-(4-hydroxyphenyl)propylamino)ethanol] enhances protein accretion in skeletal muscle (sm) of pigs. Experiments were conducted to elucidate fractional protein synthesis (FSR) and mRNA abundance for alpha-actin in sm of pigs fed a 16% protein diet containing 20 parts/million ractopamine for 21 days. Pigs were infused for 6 h with [14C]lysine (80 microCi/h.pig); after infusion pigs were killed, and longissimus dorsi muscle samples were obtained for RNA isolation and measurement of [14C]lysine incorporation. FSR was determined in vivo by incorporation of [14C]lysine from the muscle free amino acid pool into purified sm alpha-actin. FSR of sm alpha-actin was 55% greater in ractopamine-treated pigs than in controls. Relative mRNA abundance of alpha-actin was determined by dot blot hybridization of 0.1-0.4 microgram RNA to human sm alpha-actin [32P]cDNA probe. Longissimus dorsi alpha-actin mRNA abundance was 2-fold greater in pigs fed ractopamine. Sm RNA was translated in vitro using a cell-free assay to determine pretranslational effects on other muscle proteins. Effects of ractopamine on muscle protein synthesis are not specific to sm alpha-actin, because other muscle proteins also were increased using the in vitro translation assay. These results indicate that the increase in sm accretion in pigs fed ractopamine is due in part to an increase in myofibrillar protein synthesis and that some of the increase can be accounted for by an increase in mRNA abundance for sm alpha-actin.

Digesta containing microbial protein, undegraded (bypass) feed protein, some free amino acids and oligopeptides, and microbial nucleic acids passes from the rumen-reticulum through the omasum to the lower gut (abomasum and small intestine). The rate of neutralization of abomasal digesta flow is slower in ruminants than in nonruminants, and activation and peak activity of the pancreatic proteases is delayed to the mid jejunum. The overall apparent digestibility in the small intestine of proteins and microbial or exogenous nuclei acids is 60-70% and 75-85% respectively. Absorption mechanisms in ruminants for protein and nucleic acid digestion end products appear similar to those described in nonruminants, but the highest rate of amino acid uptake was found in the mid to lower ileum. Essential amino acids (Met, THr, Val, Ile, Leu, Phe, Lys, His, Arg) are absorbed faster than nonessential amino acids (Gly, Glu, Asp, Ser, Pro, Cys, Tyr). After feeding, plasma amino acids remain unchanged or decline in a mature ruminant, while in nursing lambs, plasma free amino acids levels increase after a meal.

The effect of testosterone administration on muscle development and protein synthesis was studied with intact male rabbits. Rabbits were randomized into three experimental groups; day 0 control (G-1), day 15 control (G-2) and day 15 testosterone (G-3). Testosterone (delta4-Androsten-17beta-ol-3-one in silastic tubing) was surgically implanted into the G-3 rabbits. On day (G-1) and day 15 (G-2 and 3) of the experiment all rabbits were injected IP with 50 mu Ci-3H-leucine. Rabbits were sacrificed at intervals after the 3H-leucine injection. Right and left semitendinosus muscles, pituitary and adrenal glands, testicles and blood samples were obtained for analysis. Testosterone improved (P less than .01) gain and feed efficiency, depressed testicle weight (P less than .01), increased serum testosterone and insulin (P less than 0.01) but did not affect adrenal and pituitary weights. Muscle moisture, fat and total protein, myofibrillar, sarcoplasmic and stromal protein fractions and RNA and DNA content were not significantly affected by testosterone although G-3 semitendinosus muscle had the highest total and myofibrillar protein, RNA, and DNA content. The testosterone treated rabbits (G-3) had higher (P less than 0.05) 3H-leucine incorporation into myofibrillar protein and lower 3H-leucine incorporation into sarcoplasmic protein than the day 0 and day 15 controls.

Tissue free amino acid pools account for only a small fraction of the total amino acid content in the body. Blood of plasma free amino acid pools represent only a very small proportion of tissue free amino pools. Plasma free amino acid profiles have been used as a tool to study nutritional and metabolic aspects of protein status. Static measurements of plasma amino acid levels have limited value as sensitive indicators of protein status because such measurements do not reflect the magnitude of amino acid fluxes in and out free amino acid pools. Use of plasma amino acid profiles, under well defined experimental conditions, in assessing limiting amino acids and essential amino acid requirements in ruminants is discussed.

Young female obese (ob/ob) and lean mice were fed a single diet containing 10 or 20% casein or were allowed to self-select from two diets containing 10 and 50, 20 and 60, or 30 and 70% casein for 3 weeks. Obese and lean mice offered a choice of two diets varying in protein-consumed 36% and 32%, respectively, of energy from protein. Although both obese and lean mice consumed more protein when allowed to self-select, each group maintained the same energy intake as observed when a single diet was fed. Because obese mice consumed more energy than lean mice, their self-selected intake of protein was 55% greater than observed in lean mice. The increased protein intake in self-selected obese mice was associated with a decreased tryptophan:large neutral amino acid ratio in their plasma. Average nitrogen retention was only slightly less in obese mice than in lean mice, but the sites of nitrogen deposition differed considerably. Obese mice retained only 35% of their nitrogen in the carcass (skeletal muscle and skeleton) while lean mice retained 58% of their nitrogen in the carcass. In summary, young obese mice allowed to self-select from two diets varying in protein and carbohydrate consumed more protein and more energy, but deposited less nitrogen in their carcasses, than lean mice. Hyperphagia in young obese mice is not directly linked to an increased demand for dietary protein.

N tau-methylhistidine (NMH) concentrations were determined in acid hydrolysates of 12 common feedstuffs for ruminants, and duodenal digesta from steers fed alfalfa haylage and high-moisture corn. For six species of grass hays, NMH concentrations ranged from nondetectable (ND; less than .1 nmol/g dry matter) to .6 nmol/g dry matter. Two legume hays had NMH concentrations of .9 and 2.0 nmol/g dry matter, respectively. For corn silage, high-moisture corn, beet pulp and soybean meal, NMH concentrations were 1.3, 1.1, 1.5 and 2.2 nmol/g dry matter, respectively. Duodenal digesta NMH concentrations ranged from ND to 1.2 nmol/g dry matter. When pure NMH (1 mM) was incubated with rumen fluid in vitro for 8 h, only 14% was degraded while leucine (1 mM) was totally degraded. From the feedstuffs used in this study, results show that exogenous (dietary) NMH is not a concern in skeletal muscle protein turnover studies in cattle using urinary NMH excretion because it can be calculated that potential NMH intake from the preceding feedstuffs would be less than 1% of normal urinary excretion and that ruminal microbes are not a potential source of NMH. NMH was resistant to in vitro ruminal degradation. The in vitro ruminal NMH degradation results suggest that when feedstuffs containing at least 15 nmol/g dry matter are fed (far greater than values observed in this study) a significant proportion of urinary NMH would arise directly from exogenous sources and would invalidate the use of this technique in assessing protein turnover in cattle.

In this study, 243 women with symptomatic trichomonal vaginitis were treated with eight 250 mg. tablets of metronidazole for themselves, and eight tablets were given to each of their male consorts. They were given instructions to ingest "all eight in a row" and "avoid alcohol for 48 hours." Ninety-five per cent of 203 women that returned for re-examination were cured. This single-dose treatment is effective, well tolerated, and less expensive than current recommended dosages.

N tau-methylhistidine (N tau MH) was used as an index for muscle protein degradation and this index was utilized to evaluate degradation rates in young growing cattle. Initially, two Charolais crossbred heifers, 12 months of age, were used to measure the recovery of radioactivity in the urine for a 120-hour period after intravenous injection of [14C]N tau MH. Of the radioactivity injected into the animals, 89.7% was recovered after 120 hours. With rate and amount of clearance as the criteria, the excretion of N tau MH in urine appears to be a valid index of muscle protein degradation in cattle. Eight steers of two genetic types were used to evaluate the effect of frame size on turnover rates of muscle proteins with N tau MH as an index. Large frame cattle (LG) excreted more N tau MH per day (P less than 0.03) throughout the trial. Total daily creatinine excretion was less for small frame (SM) cattle (P less than 0.02) showing an increase with time (P less than 0.01) in LG and SM cattle. N tau MH-to-creatinine ratios showed a decline with time. Fractional breakdown rates (FBR) and fractional synthesis rates (FSR) appeared to parallel each other with rates tending to decrease with age. No differences were observed between LG and SM cattle for FBR, FSR or fractional growth rate (FGR).

Encephalopathy developed in 3 patients after transurethral prostatic resection. Each patient had blood ammonia levels more than 10 times the upper limit of normal. Data supportive of a metabolic cause for encephalopathy subsequently were obtained in a prospective study of patients undergoing transurethral prostatic resection with glycine irrigation. It is suggested that a distinct subpopulation of patients experiencing transurethral prostatic resection syndrome can be identified. These patients exhibit encephalopathic symptoms and have concurrent marked elevation of blood ammonia levels.

Feeding for 150 days of 25 g per day of methionine hydroxy analog was tested on 100 cows (52 treated and 48 controls) in the Brigham Young University herd. Effect of days after parturition of initiating methionine hydroxy analog feeding also was observed. Milk yields were not affected by methionine hydroxy analog, but fat percent and fat yields were increased 21 and 17% by the additive. Abnormally low milk fat by control cows (2.84%) magnified the response to methionine hydroxy analog feeding. Feeding methionine hydroxy analog beginning 0 to 12 days postpartum elicited much larger increases of milk fat than started later (17 to 102 days). Blood from the coccygeal vein of 20 cows from each treatment had 10% more triglycerides from cows fed methionine hydroxy analog than from control cows. Increases of arterio-venous differences across the mammary gland of triglycerides and lipoproteins of blood serum suggested that increases of milk fat could have resulted from greater uptake of performed fat by the udder. Feeding methionine hydroxy analog increased methionine, isoleucine, and leucine in serum of coccygeal vein, but methionine was the only amino acid with significantly higher arteriovenous differences across the mammary gland.

Five-week-old female lean and obese (ob/ob) mice were fed a 20% protein diet (1.1% tyrosine) or a 20% protein diet supplemented with tyrosine (4% tyrosine). On d 4 of supplementation, brain norepinephrine (NE) synthesis rate and brain efflux of 3-methoxy-4-hydroxyphenylethyleneglycol (MHPG), a major metabolite of NE in mouse brain, were measured after administration of the monoamine oxidase inhibitor pargyline. Control obese mice had a lower rate of NE synthesis and a lower MHPG efflux than lean controls. Tyrosine supplementation elevated brain tyrosine concentration twofold, but had no effect on NE synthesis rate or MHPG efflux in either group. Likewise, tyrosine supplementation for up to 1 mo had no effect on food intake, oxygen consumption or body weight in obese mice and only a transient effect in lean mice, in which oxygen consumption was higher on d 2 and 3 and food intake was higher on d 3 and 4 compared with nonsupplemented lean mice. We conclude that tyrosine availability is not a limiting factor in the reduced brain noradrenergic activity of obese mice.

Chickens (1,200 g) were fasted 1, 4, or 8 days. Significant decreases occurred in total body protein and fat with fasting, with the greatest energy loss from fat. Glucose production determined with either [2-3H] or [6-3H] glucose injected simultaneously with [U-14C] glucose remained constant with fasting at 10 to 13 mg/minute/kg body weight which is much higher than reported for mammals. Blood lactate and glycerol were unchanged with fasting, while pyruvate increased and plateaued. Plasma alanine, serine and glycine levels were extremely high compared to values in fasted mammals. Blood beta-hydroxybutyrate increased dramatically with fasting (350 to 3,500 nm/ml), while acetoacetate remained constant. The hepatic lactate: pyruvate ratio was unchanged with fasting, while the beta-hydroxybutyrate:acetoacetate ratio increased. These ratios have been reported to influence phosphoenolpyruvate (PEP) and glucose production in mammals. Hepatic and renal phospyoenolpyruvate carboxykinase (PEPCK) levels remained constant, while hepatic lactate dehydrogenase increased with fasting. Beta-Hydroxybutyrate dehydrogenase levels were very low at all times. The results indicate little glucose sparing adaptation per kg in the fasting chicken.

A 6-h continuous infusion of L-[U-14C]tyrosine was used to estimate fractional protein synthesis rates (FSR) in the longissimus dorsi (LD), semitendinosus (ST) and brachialis (BR) muscles of intact male pigs weighing 22 or 45 kg. The FSR was approximately 20% lower for pigs at 45 kg (4.2 vs. 5.2%/d, 5.2 vs. 6.4%/d and 5.1 vs. 6.4%/d for the LD, ST and BR muscles, respectively) compared with pigs at 22 kg. Fractional protein accretion or growth rates (FGR) were estimated over a 2-wk period. At 22 kg, FGR for the LD, ST and BR were 0.7, 2.4 and 1.7%/d, respectively; at 45 kg, FGR for these muscles were 1.7, 1.9 and 0.7%/d. Fractional protein breakdown rates (FBR) derived by difference (FBR = FSR - FGR) were 44, 16 and 8% lower for the LD, ST and BR muscles, respectively, at 45 kg compared with those at 22 kg. Therefore, it is suggested that muscle growth rate is modulated by alterations in FBR. By using the fractional rates found in these muscles to determine total-muscle protein synthesized or degraded in pigs at 22 and 45 kg, the proportion of protein retained was approximately 28% of that synthesized by the pigs at each weight. Since individual skeletal muscles of the pigs differed in protein turnover rates during postnatal growth and development, selection of a muscle(s) for turnover rates in growth studies is critical.

Young female obese (ob/ob) and lean mice were allowed to self-select from two diets varying in protein and carbohydrate, protein and fat or carbohydrate and fat for 36 days. Obese and lean mice offered a choice between two diets varying in protein and carbohydrate consumed 35 and 30%, respectively, of energy from protein. When two diets varying in protein and fat were fed, both obese and lean mice initially self-selected a higher percentage of energy from protein than when diets varying in protein and carbohydrate were fed. This pattern was rapidly reversed in lean mice and more gradually reversed in obese mice. By the end of this feeding trial, obese and lean mice were self-selecting 26 and 16%, respectively, of energy from protein. When two diets varying in carbohydrate and fat were fed, young obese mice self-selected only 44 +/- 6% of energy from the high fat diet whereas lean mice self-selected 65 +/- 4% of energy from the high fat diet. The ratio of plasma tryptophan to large neutral amino acids (valine, leucine, isoleucine, phenylalanine and tyrosine) showed a strong inverse relationship to protein intake. In summary, replacement of dietary carbohydrate with fat lowered the percentage of energy self-selected as protein. Obese mice, however, continued to consume more energy and more protein than lean mice.

Adult obese (ob/ob) and lean mice were allowed to self-select between diets varying in level of protein and carbohydrate, or protein and fat. Obese and lean mice self-selected 29% and 26% of their energy, respectively, from protein when fed diets varying in protein and carbohydrate. Intake of protein decreased 45% in obese mice and 32% in lean mice when diets varying in level of protein and fat were fed. These reductions in protein intake were not associated with an elevation in brain serotonin (5-HT), a putative regulator of protein intake. When the tryptophan content of diets varying in protein and carbohydrate was quadrupled in an attempt to elevate brain 5-HT and thereby reduce protein intake in obese and lean mice, neither the level of brain 5-HT nor protein intake were affected. Under the conditions of these experiments we found no evidence that protein intake was inversely related to brain 5-HT levels in obese and lean mice, nor were we able to manipulate protein intake with dietary tryptophan supplementation. The reduced protein intake in obese and lean mice fed diets varying in level of protein and fat, rather than protein and carbohydrate, may result from their greater preference for a high-fat diet than for a high-carbohydrate diet.

Forty crossbred barrows (average initial weight, 66.4 kg) were utilized to determine the effects of ractopamine (a phenethanolamine/beta adrenergic agonist) on protein accretion and synthesis, activities of cathepsins B, H, L and calcium-dependent proteinase and nucleic acid content of semitendinosus muscle (ST). All pigs were offered a 16% protein, mineral and vitamin fortified corn-soybean meal diet supplemented with either 0 or 20 ppm ractopamine for 14, 21, 28, 35 or 42 d. Protein synthesis (fractional rates) was studied in pigs at d 21 and 35; ST protease activities, protein and nucleic acid content were measured on d 14, 28 and 42. Ractopamine increased (P less than .01) ST total protein content and maintained RNA muscle concentration and total ST muscle RNA content. DNA content (mg/g ST) declined (P less than .05) upon ractopamine feeding, but total DNA per muscle remained unchanged except for d 42, when the ST muscles were largest. Fractional accretion rates (FAR) were 1.0 and 1.2% for control and ractopamine-fed pigs, respectively. Fractional protein synthesis rate (FSR) was higher (P less than .06) in ractopamine-fed pigs (6.1%/d) than in control pigs (4.4%/d). Fractional protein synthesis rate could account for the observed muscle hypertrophy and increased FAR. Estimated fractional breakdown rates (FBR = FSR - FAR) were 3.4%/d and 4.9%/d for control and ractopamine-fed pigs, respectively. The activities of the catheptic proteases and calcium-dependent proteinase were not affected by the treatments.