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1.
Proc Natl Acad Sci U S A ; 117(45): 28183-28190, 2020 11 10.
Article in English | MEDLINE | ID: mdl-33109722

ABSTRACT

The idea that tropical forest and savanna are alternative states is crucial to how we manage these biomes and predict their future under global change. Large-scale empirical evidence for alternative stable states is limited, however, and comes mostly from the multimodal distribution of structural aspects of vegetation. These approaches have been criticized, as structure alone cannot separate out wetter savannas from drier forests for example, and there are also technical challenges to mapping vegetation structure in unbiased ways. Here, we develop an alternative approach to delimit the climatic envelope of the two biomes in Africa using tree species lists gathered for a large number of forest and savanna sites distributed across the continent. Our analyses confirm extensive climatic overlap of forest and savanna, supporting the alternative stable states hypothesis for Africa, and this result is corroborated by paleoecological evidence. Further, we find the two biomes to have highly divergent tree species compositions and to represent alternative compositional states. This allowed us to classify tree species as forest vs. savanna specialists, with some generalist species that span both biomes. In conjunction with georeferenced herbarium records, we mapped the forest and savanna distributions across Africa and quantified their environmental limits, which are primarily related to precipitation and seasonality, with a secondary contribution of fire. These results are important for the ongoing efforts to restore African ecosystems, which depend on accurate biome maps to set appropriate targets for the restored states but also provide empirical evidence for broad-scale bistability.


Subject(s)
Climate , Ecosystem , Forests , Grassland , Africa , Fires , Rain , Seasons , Trees , Tropical Climate
2.
Nat Ecol Evol ; 4(11): 1472-1476, 2020 11.
Article in English | MEDLINE | ID: mdl-32839542

ABSTRACT

Forest restoration occupies centre stage in global conversations about carbon removal and biodiversity conservation, but recent research rarely acknowledges social dimensions or environmental justice implications related to its implementation. We find that 294.5 million people live on tropical forest restoration opportunity land in the Global South, including 12% of the total population in low-income countries. Forest landscape restoration that prioritizes local communities by affording them rights to manage and restore forests provides a promising option to align global agendas for climate mitigation, conservation, environmental justice and sustainable development.


Subject(s)
Conservation of Natural Resources , Forests , Biodiversity , Carbon , Humans
3.
Risk Anal ; 38(10): 2087-2104, 2018 10.
Article in English | MEDLINE | ID: mdl-29772062

ABSTRACT

In the United Kingdom, dwelling fires are responsible for the majority of all fire-related fatalities. The development of these incidents involves the interaction of a multitude of variables that combine in many different ways. Consequently, assessment of dwelling fire risk can be complex, which often results in ambiguity during fire safety planning and decision making. In this article, a three-part Bayesian network model is proposed to study dwelling fires from ignition through to extinguishment in order to improve confidence in dwelling fire safety assessment. The model incorporates both hard and soft data, delivering posterior probabilities for selected outcomes. Case studies demonstrate how the model functions and provide evidence of its use for planning and accident investigation.

4.
Exp Neurol ; 293: 144-158, 2017 07.
Article in English | MEDLINE | ID: mdl-28412220

ABSTRACT

Peripheral inflammation induces sensitization of nociceptive spinal cord neurons. Both spinal tumor necrosis factor (TNF) and neuronal membrane insertion of Ca2+ permeable AMPA receptor (AMPAr) contribute to spinal sensitization and resultant pain behavior, molecular mechanisms connecting these two events have not been studied in detail. Intrathecal (i.t.) injection of TNF-blockers attenuated paw carrageenan-induced mechanical and thermal hypersensitivity. Levels of GluA1 and GluA4 from dorsal spinal membrane fractions increased in carrageenan-injected rats compared to controls. In the same tissue, GluA2 levels were not altered. Inflammation-induced increases in membrane GluA1 were prevented by i.t. pre-treatment with antagonists to TNF, PI3K, PKA and NMDA. Interestingly, administration of TNF or PI3K inhibitors followed by carrageenan caused a marked reduction in plasma membrane GluA2 levels, despite the fact that membrane GluA2 levels were stable following inhibitor administration in the absence of carrageenan. TNF pre-incubation induced increased numbers of Co2+ labeled dorsal horn neurons, indicating more neurons with Ca2+ permeable AMPAr. In parallel to Western blot results, this increase was blocked by antagonism of PI3K and PKA. In addition, spinal slices from GluA1 transgenic mice, which had a single alanine replacement at GluA1 ser 845 or ser 831 that prevented phosphorylation, were resistant to TNF-induced increases in Co2+ labeling. However, behavioral responses following intraplantar carrageenan and formalin in the mutant mice were no different from littermate controls, suggesting a more complex regulation of nociception. Co-localization of GluA1, GluA2 and GluA4 with synaptophysin on identified spinoparabrachial neurons and their relative ratios were used to assess inflammation-induced trafficking of AMPAr to synapses. Inflammation induced an increase in synaptic GluA1, but not GluA2. Although total GluA4 also increased with inflammation, co-localization of GluA4 with synaptophysin, fell short of significance. Taken together these data suggest that peripheral inflammation induces a PI3K and PKA dependent TNFR1 activated pathway that culminates with trafficking of calcium permeable AMPAr into synapses of nociceptive dorsal horn projection neurons.


Subject(s)
Cyclic AMP-Dependent Protein Kinases/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Posterior Horn Cells/metabolism , Radiculopathy/pathology , Receptors, AMPA/metabolism , Tumor Necrosis Factor-alpha/metabolism , Animals , Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Calcium/metabolism , Carrageenan/toxicity , Disease Models, Animal , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/therapeutic use , Etanercept/therapeutic use , Female , Male , Mice , Posterior Horn Cells/pathology , Posterior Horn Cells/ultrastructure , Protein Transport/drug effects , Protein Transport/physiology , Radiculopathy/chemically induced , Radiculopathy/drug therapy , Rats, Sprague-Dawley , Subcellular Fractions/drug effects , Subcellular Fractions/metabolism , Synaptophysin/metabolism , Tumor Necrosis Factor-alpha/pharmacology
5.
Exp Neurol ; 283(Pt A): 276-86, 2016 09.
Article in English | MEDLINE | ID: mdl-27349406

ABSTRACT

Alterations in the neuro-immune balance play a major role in the pathophysiology of chronic neuropathic pain. MicroRNAs (miRNA) can regulate both immune and neuronal processes and may function as master switches in chronic pain development and maintenance. We set out to analyze the role of miR-132-3p, first in patients with peripheral neuropathies and second in an animal model of neuropathic pain. We initially determined miR-132-3p expression by measuring its levels in white blood cells (WBC) of 30 patients and 30 healthy controls and next in sural nerve biopsies of 81 patients with painful or painless inflammatory or non-inflammatory neuropathies based on clinical diagnosis. We found a 2.6 fold increase in miR-132-3p expression in WBC of neuropathy patients compared to healthy controls (p<0.001). MiR-132-3p expression was also slightly up-regulated in sural nerve biopsies from neuropathy patients suffering from neuropathic pain compared to those without pain (1.2 fold; p<0.001). These promising findings were investigated further in an animal model of neuropathic pain, the spared nerve injury model (SNI). For this purpose miR-132-3p expression levels were measured in dorsal root ganglia and spinal cord of rats. Subsequently, miR-132-3p expression was pharmacologically modulated with miRNA antagonists or mimetics, and evoked pain and pain aversion were assessed. Spinal miR-132-3p levels were highest 10days after SNI, a time when persistent allodynia was established (p<0.05). Spinal administration of miR-132-3p antagonists via intrathecal (i.t.) catheters dose dependently reversed mechanical allodyina (p<0.001) and eliminated pain behavior in the place escape avoidance paradigm (p<0.001). Intrathecal administration of miR-132-3p mimetic dose-dependently induced pain behavior in naïve rats (p<0.001). Taken together these results indicate a pro-nociceptive effect of miR-132-3p in chronic neuropathic pain.


Subject(s)
Leukocytes/metabolism , MicroRNAs/metabolism , Neuralgia/blood , Neuralgia/physiopathology , Up-Regulation/physiology , Activating Transcription Factor 3/metabolism , Adult , Aged , Aged, 80 and over , Animals , Avoidance Learning/physiology , Chronic Disease , Cohort Studies , Disease Models, Animal , Female , Ganglia, Spinal/drug effects , Ganglia, Spinal/metabolism , Humans , Male , MicroRNAs/chemistry , MicroRNAs/genetics , Middle Aged , Neuralgia/pathology , Oligonucleotides/pharmacology , Pain Measurement , Pain Threshold/drug effects , Pain Threshold/physiology , RNA, Messenger/metabolism , Rats , Receptors, AMPA/metabolism , Up-Regulation/drug effects
6.
J Anim Sci ; 94(12): 5382-5392, 2016 Dec.
Article in English | MEDLINE | ID: mdl-28046162

ABSTRACT

Three experiments evaluated the effects of ractopamine hydrochloride (RAC) dose and duration on growth performance and carcass characteristics of feedlot steers. In total, 1,509 crossbred steers (530 kg initial BW [SD 22]) were used in a randomized complete block design using a 3 × 3 factorial treatment structure. Treatments consisted of RAC dose (0, 100, or 200 mg/steer daily) and duration (28, 35, or 42 d) of RAC feeding prior to harvest. Initiation of RAC dose was staggered (7 d apart) based on RAC duration, which resulted in common days on feed among treatments. Data from the 3 experiments were combined for statistical analyses. There were no RAC dose × duration interactions ( ≥ 0.85) for growth performance. Live final BW was not different ( ≥ 0.24) as RAC dose increased. Dry matter intake linearly decreased ( < 0.01) as RAC dose increased. Live ADG and G:F linearly increased ( ≤ 0.01) as RAC dose increased. Carcass-adjusted ADG and G:F linearly increased ( ≤ 0.02) as RAC dose increased. Compared with steers fed 0 mg RAC/steer daily, G:F was improved by 5.0 and 13.0% when steers were fed 100 ( = 0.31) and 200 ( = 0.01) mg RAC/steer daily, respectively. Hot carcass weight tended ( = 0.10) to linearly increase as RAC dose increased, with carcasses from steers fed 100 ( = 0.38) and 200 ( = 0.10) mg RAC/steer daily being 2.2 and 4.1 kg heavier, respectively, than carcasses from steers fed 0 mg RAC/steer daily. Increasing RAC dose linearly ( < 0.01) increased LM area and linearly ( = 0.02) decreased marbling score. Live final BW was not different ( ≥ 0.60) among RAC durations. Carcass-adjusted final BW, ADG, and G:F were not different ( ≥ 0.41) as RAC duration increased. Carcass traits did not differ ( ≥ 0.18) among RAC duration. Feeding 200 mg RAC/steer daily improved ADG, feed efficiency, and HCW. Increasing the feeding duration of RAC had no effect of growth performance or carcass characteristics. These data indicate that feeding 200 mg RAC/steer daily for 28 d improves steer growth performance.


Subject(s)
Body Composition/drug effects , Cattle/growth & development , Phenethylamines/pharmacology , Adrenergic beta-Agonists/administration & dosage , Adrenergic beta-Agonists/pharmacology , Animal Feed/analysis , Animal Nutritional Physiological Phenomena , Animals , Diet/veterinary , Dose-Response Relationship, Drug , Male , Phenethylamines/administration & dosage , Weight Gain/drug effects
7.
Meat Sci ; 110: 201-11, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26253836

ABSTRACT

The objective of this study was to determine if maternal energy status during mid-gestation influences the expression of genes regulating muscle and fat development, and muscle characteristics that may impact meat tenderness. Cows grazed dormant, native range (Positive Energy Status [PES]) or were fed at 80% of maintenance energy requirements (Negative Energy Status [NES]) during mid-gestation. Steer offspring were harvested after 21 d in the feedlot (weaning subsample) or after 208 d in the feedlot (final subsample). Greater 21-d tenderness was observed in NES steers, resulting from reduced collagen content in longissimus lumborum steaks. In the semitendinosus, NES steers had greater soluble collagen, and down-regulated expression of MHC-IIA and TIMP-3 at weaning, while MHC-IIA expression was up-regulated in NES steers in the final harvest. Data show mid-gestational maternal energy status may impact offspring tenderness and collagen, but differences were not detected in expression of genes important in myogenesis and adipogenesis in muscle samples obtained from steers at weaning or slaughter.


Subject(s)
Energy Metabolism , Gene Expression Regulation/physiology , Meat/standards , Muscle, Skeletal/physiology , Animal Nutritional Physiological Phenomena , Animals , Cattle , Female , Maternal Nutritional Physiological Phenomena , Pregnancy
8.
J Anim Sci ; 93(2): 786-93, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25548203

ABSTRACT

Research has suggested that maternal undernutrition may cause the development of a thrifty phenotype in the offspring, potentially resulting in greater adiposity and reduced muscle mass. These alterations in adipose and muscle development could have lasting impacts on offspring growth, carcass characteristics, and meat quality. However, limited research exists evaluating the impact of maternal energy status on these economically important traits of the offspring. Therefore, the objective of this study was to determine the influence of maternal energy status during midgestation on offspring carcass characteristics and meat quality. To alter maternal energy status, cows either grazed dormant, winter range (positive energy status [PES]) or were fed in a drylot at 80% of the energy requirements for BW maintenance (negative energy status [NES]) during a mean period of 102 ± 10.9 to 193 ± 10.9 d of gestation. Changes in BCS, BW, LM area (LMA), and 12th rib backfat were measured throughout midgestation. At the end of midgestation, cows in the NES group had a reduction (P ≤ 0.05) in BCS, BW, LMA, and 12th rib backfat when compared with PES dams. Cows and calves were managed similarly after midgestation through weaning and calves were managed and fed a common diet through the receiving, backgrounding, and finishing phases in the feedlot. Calves were harvested after 208 d in the feedlot, carcass characteristics were recorded, and strip loins were recovered for analysis of objective color and Warner-Bratzler shear force (WBSF). Maternal energy status had no influence on offspring HCW, dressing percent, LMA, percent KPH, marbling score, percent intramuscular fat, objective color, or WBSF (P > 0.10). Progeny of NES cows tended to have improvements in 12th rib backfat and USDA yield grade (P < 0.10). Greater ratio of marbling score to 12th rib fat thickness and ratio of percent intramuscular fat to 12th rib fat thickness (P < 0.05) were discovered in progeny from cows experiencing a NES during midgestation. These results suggest that maternal energy status during midgestation may impact fat deposition in intramuscular and subcutaneous fat depots without impacting muscle mass.


Subject(s)
Animals, Newborn/physiology , Body Composition/physiology , Cattle/physiology , Energy Metabolism/physiology , Maternal Nutritional Physiological Phenomena/physiology , Meat/standards , Pregnancy, Animal/physiology , Adiposity/physiology , Animals , Animals, Newborn/growth & development , Body Weight/physiology , Cattle/growth & development , Female , Fetal Development/physiology , Food Industry/standards , Food Quality , Male , Muscle, Skeletal/physiology , Pregnancy
9.
J Anim Sci ; 92(11): 5275-84, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25253804

ABSTRACT

Subcutaneous fat and marbling both increase in beef cattle during the feeding phase but are antagonistic in regard to their contribution to beef carcass value. The objective of this study was to determine whether cellular factors associated with marbling development change with growth stage throughout the feeding period and whether they are correlated to marbling relative to carcass composition. Twenty-four steers of known origin with the cytosine and thymine (CT) leptin genotype were allotted to 3 harvest groups. Six steers per harvest group were harvested at the following predetermined points: 35 d on feed (early feeding period, EF), average live weight of 464 kg (middle feeding period, MF), and 1.17-cm 12th-rib subcutaneous fat thickness (late feeding period, LF). Longissmus muscle samples were collected within 30 min postmortem and snap frozen for real-time PCR and Western blot analysis of lipoprotein lipase, adenosine monophosphate-activated protein kinase α (AMPKα), stearoyl-coenzyme A desaturase (SCD), PPARγ, C/EBP-ß, and myostatin. Carcass data were recorded, and LM samples were collected and aged 2, 7, 14, and 21 d postmortem for Warner-Bratzler shear force determination. Carcass composition was estimated by dissection of the 9-10-11 rib section and subsequent proximate analysis of the soft tissue. Intramuscular fat content of the LM increased linearly throughout the feeding period, giving additional support to marbling as an early developing tissue. Expression of AMPKα was found to be downregulated, whereas SCD expression was upregulated in the LF group relative to the first 2 harvest groups. Additionally, SCD and PPARγ were downregulated in the EF group relative to the latter 2 harvest groups. These changes in gene expression resulted in a linear increase in only PPARγ protein abundance, whereas myostatin tended to increase quadratically. A correlation was found between intramuscular fat and PPARγ abundance. This gives further evidence of the importance of adipocyte hyperplasia in increasing marbling. Targeting and increasing PPARγ expression may serve as a mechanism to increase marbling deposition. Last, LF steaks were more tender than MF or EF steaks, indicating improved tenderness with increased days on feed.


Subject(s)
Adipose Tissue/physiology , Body Composition/physiology , Cattle/growth & development , Meat/analysis , Animals , Body Weight/physiology , Cattle/physiology , Eating/physiology , Genotype , Male , Muscle, Skeletal/enzymology , Subcutaneous Fat/anatomy & histology
10.
J Anim Sci ; 89(12): 4142-50, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21821813

ABSTRACT

Consecutive receiving studies were used to evaluate the replacement of starch (dry rolled corn; DRC) with a nonforage fiber source (soybean hulls; SBH) on performance, mineral, and blood metabolite status of newly arrived feedlot steer calves. Steers in yr 1 (Y1; 9 pens/diet, 8 to 10 animals/pen) and yr 2 (Y2; 6 pens/diet, 9 to 10 animals/pen) were blocked by weaning management, and then stratified by BW and randomly assigned to pens. Pens were randomly assigned to an oat silage-based diet containing starch (HS) from DRC or digestible fiber (HF) from SBH. Diets were formulated for 12% CP (DM basis) and to meet or exceed NRC (1996) nutrient requirements for Ca, P, and vitamins A and E. Mineral status was assessed in Y1 only via liver biopsies and serum samples collected on d 3 and 28. Mineral concentrations on d 28 were compared using d 3 concentrations as a covariate. Glucose, NEFA, and plasma urea N status were assessed in Y2 only via blood collections on d 0, 3, 7, 14, 28, and 59. Morbidity (<10%) and mortality rates were not different (P > 0.10) between treatments across years. Daily BW gain was similar (P > 0.10) between treatments both during the receiving period and cumulatively across years. Overall, feed intake was greater (P = 0.007) for steers fed HF compared with steers fed HS in Y1, but was not different in Y2 (P = 0.13). Steers consuming the HS diet tended (P = 0.07) to have better BW gain efficiency in Y1 only. Across years, BW gain efficiency and ADG were similar between treatments (P > 0.10), although DMI was greater for steers fed HF (P = 0.003). Based on 2 yr of performance, the calculated ME content of SBH was estimated at 92.5% of the ME value of DRC (2.74 vs. 2.96 Mcal/kg, respectively). Mineral concentrations on d 28 were similar (P > 0.10) for most minerals assayed. There was a steeper (P = 0.005) decline in hepatic Cu concentrations early in the feeding period for steers fed HF, resulting in decreased (P = 0.001) d 28 hepatic concentrations. Hepatic Mn was greater (P = 0.003) in steers fed HF on d 28 as a result of greater (P = 0.006) Mn accumulation during the initial 28 d on feed. Blood metabolites in Y2 (using d 0 values as a covariate) were similar (P > 0.10) across treatments, except for reduced (P = 0.025) plasma urea N concentrations on d 7 and greater (P = 0.050) NEFA concentrations on d 28 for steers fed HS. These studies indicate that the use of SBH in receiving diets can support BW gain similar to the use of DRC.


Subject(s)
Animal Feed/analysis , Cattle/physiology , Glycine max , Zea mays , Animal Nutritional Physiological Phenomena , Animals , Diet/veterinary , Food Handling , Male , Weight Gain
11.
J Anim Sci ; 89(12): 3954-72, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21724941

ABSTRACT

Data from species other than cattle indicate that ghrelin and GH secretagogue receptor (GHS-R) could play a key role in fat deposition, energy homeostasis, or glucose metabolism by directly affecting liver and adipose tissue metabolism. Beef steers (n = 72) were used to test the hypothesis that plasma ghrelin and leptin concentrations and abundance of the GHS-R in liver, muscle, and adipose tissues differ in steers exhibiting differences in composition of gain. At trial initiation (d 0), 8 steers were slaughtered for initial carcass composition. The remaining 64 steers were stratified by BW, allotted to pen, and treatment was assigned randomly to pen. Steers were not implanted with anabolic steroids. Treatments were 1) a low-energy (LE) diet fed during the growing period (0 to 111 d) followed by a high-energy (HE) diet during the finishing period (112 to 209 d; LE-HE) or 2) the HE diet for the duration of the trial (1 to 209 d; HE-HE). Eight steers per treatment were slaughtered on d 88, 111, 160, and 209. Carcass ninth, tenth, and eleventh rib sections were dissected for chemical composition and regression equations were developed to predict compositional gain. Liver, muscle, and subcutaneous adipose tissues were frozen in liquid nitrogen for subsequent Western blotting for GHS-R. Replicate blood samples collected before each slaughter were assayed for ghrelin and leptin concentrations. When compared at a common compositional fat end-point, the rate of carcass fat accretion (g·kg of shrunk BW(-1)) was greater (P < 0.001) in HE-HE steers whereas the rate of carcass protein accretion (g·kg of shrunk BW(-1)) was less (P < 0.001) compared with LE-HE steers. When compared at a common compositional fat end-point, plasma leptin, ghrelin, and insulin concentrations were greater (P < 0.05) for HE-HE compared with LE-HE steers. Abundance of the GHS-R, to which ghrelin binds, increased over time in liver and adipose tissue but did not differ as a result of treatment. Plasma ghrelin concentrations were increased for cattle continuously fed the HE diet as they became increasingly fatter; however, abundance of the GHS-R in liver, muscle, and subcutaneous adipose tissue was not different between treatment groups. The role of ghrelin in cattle metabolism warrants further investigation as it could have a significant effect on composition of BW gain, feed efficiency, and metabolic disorders such as ketosis and fatty liver.


Subject(s)
Cattle/blood , Cattle/physiology , Ghrelin/blood , Leptin/blood , Liver/metabolism , Receptors, Ghrelin/metabolism , Adipose Tissue/metabolism , Animal Feed , Animal Nutritional Physiological Phenomena , Animals , Body Composition/physiology , Diet/veterinary , Fatty Acids, Nonesterified/blood , Gene Expression Regulation/physiology , Growth Hormone/blood , Growth Hormone/metabolism , Insulin/blood , Muscle, Skeletal/metabolism , Weight Gain/physiology
12.
J Anim Sci ; 84(12): 3285-300, 2006 Dec.
Article in English | MEDLINE | ID: mdl-17093221

ABSTRACT

The objective of these experiments was to establish the relationship of plasma ghrelin concentrations with feed intake and hormones indicative of nutritional state of cattle. In Exp.1, 4 steers (BW 450 +/- 14.3 kg) were used in a crossover design to compare plasma ghrelin concentrations of feed-deprived steers with those of steers allowed to consume feed and to establish the relationship of plasma ghrelin concentrations with those of GH, insulin (INS), glucose (GLU), and NEFA. After adaptation to a once-daily feed offering (0800), 2 steers continued the once-daily feeding schedule (FED), whereas feed was withheld from the other 2 steers (FAST). Serial blood samples were collected via indwelling jugular catheter from times equivalent to 22 h through 48 h of feed deprivation. Average plasma ghrelin concentrations were greater (P < 0.001) in FAST compared with FED (690 and 123 +/- 6.5 pg/mL) steers. Average plasma ghrelin concentrations for FED steers prefeeding were elevated (P < 0.001) when compared with those postfeeding (174 and 102 +/- 4.2 pg/mL, respectively). Average plasma GH concentration was elevated (P < 0.05) for FAST steers compared with FED steers. Plasma GLU concentrations were not different; however, for FAST steers, NEFA concentrations were elevated (P < 0.001) and INS concentrations were decreased (P < 0.001). In Exp. 2, 4 steers (BW 416 +/- 17.2 kg) were used in a crossover design to determine the effects of i.v. injection of bovine ghrelin (bGR) on plasma GH, INS, GLU, and NEFA concentrations; length of time spent eating; and DMI. Steers were offered feed once daily (0800). Serial blood samples were collected from steers via indwelling jugular catheter. Saline or bGR was injected via jugular catheter at 1200 and 1400. A dosage of 0.08 microg/kg of BW bGR was used to achieve a plasma ghrelin concentration similar to the physiological concentration measured in a FAST steer in Exp. 1 (1,000 pg/mL). Injection of bGR resulted in elevated (P < 0.005) plasma GH concentrations after the 1200 but not the 1400 injection. Plasma INS, GLU, and NEFA concentrations were not affected by bGR injection. For the combined 1-h periods postinjection, length of time spent eating was greater (P = 0.02) and DMI tended to be increased (P = 0.06) for bGR steers. These data are consistent with the hypothesis that ghrelin serves as a metabolic signal for feed intake or energy balance in ruminants.


Subject(s)
Animal Nutritional Physiological Phenomena , Feeding Behavior/physiology , Peptide Hormones/blood , Animals , Blood Glucose/drug effects , Cattle , Circadian Rhythm , Cross-Over Studies , Fatty Acids, Nonesterified/blood , Food Deprivation , Ghrelin , Growth Hormone/blood , Insulin/blood , Male , Peptide Hormones/pharmacology
13.
Ir J Med Sci ; 175(3): 62-3, 2006.
Article in English | MEDLINE | ID: mdl-17073250

ABSTRACT

BACKGROUND: Anal ulceration is uncommon. Patients are typically referred because of severe anal pain, bleeding, discharge, and ulceration. It is important to exclude anal carcinoma, and to consider more unusual causes. METHODS: A 74-year-old lady presented with severe anal pain and ulceration. This was subsequently noted to be related to nicorandil, a potassium channel activator used in the treatment of angina. Discontinuation of nicorandil and faecal diversion allowed symptom relief and ulcer healing. CONCLUSION: Knowledge of the association between nicorandil and anal ulceration is essential in order to appropriately diagnose and manage this condition.


Subject(s)
Fissure in Ano/chemically induced , Myocardial Ischemia/drug therapy , Nicorandil/adverse effects , Vasodilator Agents/adverse effects , Aged , Female , Fissure in Ano/pathology , Fissure in Ano/therapy , Humans
14.
Chem Commun (Camb) ; (12): 1531-3, 2005 Mar 28.
Article in English | MEDLINE | ID: mdl-15770249

ABSTRACT

The application of FTIR spectroscopy to concentrated solutions of tetrolic acid shows, for the first time, a direct relationship between molecular self association in solution and H-bonded motifs in the subsequently crystallised solid phases.


Subject(s)
Fatty Acids, Unsaturated/chemistry , Chloroform/chemistry , Crystallization , Ethanol/chemistry , Hydrogen Bonding , Solutions/chemistry , Spectroscopy, Fourier Transform Infrared
15.
J Anim Sci ; 83(1): 108-16, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15583049

ABSTRACT

Angus and Angus x Limousin cross steers (n = 182; initial BW = 309 +/- 27.8 kg) were used to evaluate the influence of an estradiol-trenbolone acetate implant (containing 24 mg of estradiol and 125 mg of trenbolone acetate) on production efficiency and carcass traits when administered at specific stages of growth. Treatments were 1) control, no implant (NI); 2) early implant (EI) on d 1 (BW = 309 kg); or 3) delayed implant (DI) on d 57 (BW = 385 kg). Comparisons were also made between the NI and implanted treatments (I; EI + DI). Steers were procured at weaning and were backgrounded (47 d) before the initiation of the experiment. Initial predicted carcass composition was 14.9% protein, 13.3% fat, 54.6% moisture, and 17.2% bone. Days on feed were constant across treatment. After 56 d, ADG and G:F were improved (P < 0.01) by implants, NI vs. EI (1.68 vs. 1.90 kg and 0.227 vs. 0.257). At d 57, predicted carcass composition did not differ among treatments. From 57 to 112 d, DI caused higher ADG than NI or EI (NI = 1.65, EI = 1.57, and DI = 1.78 kg; P < 0.05) and higher G:F (NI = 0.155, EI = 0.150, and DI = 0.173; P < 0.01). Cumulative ADG and G:F were improved by implants (1.65 vs. 1.73 kg; P < 0.05) and (0.175 vs. 0.186; P < 0.01) for NI vs. I, respectively, with no differences between treatments that involved implants. Cumulative DMI was similar for all treatments. Implanting increased dressing percentage (63.5 vs. 64.1%; P < 0.05) and increased (P < 0.01) hot carcass weight (341 vs. 353 kg) and LM area (76.5 vs. 81.4 cm(2)) for NI vs. I, respectively. Rib fat and kidney, pelvic, and heart fat were not affected by treatment, and treatment had no effect on the whole carcass proportions of fat, protein, or water. Implants advanced maturity scores (NI = A(51) vs. EI + DI = A(59); P < 0.01). Marbling scores were decreased (P < 0.05) by EI but not by DI (NI = Small(65), EI = Small(20), DI = Small(36)). The percentage of i.m. fat content of the LM was decreased (P < 0.10) by EI and was not affected by DI (NI = 5.1, EI = 4.0, DI = 4.8%). Treatment affected (P < 0.10) the proportion of carcasses with marbling scores greater than Modest(0) (NI = 23.6, EI = 7.8, DI = 22.6%). The results of this study suggest that growth of i.m. fat is sensitive to anabolic growth promotants administered during early periods of growth.


Subject(s)
Anabolic Agents/pharmacology , Body Composition/drug effects , Cattle/growth & development , Estradiol/pharmacology , Trenbolone Acetate/analogs & derivatives , Weight Gain/drug effects , Adipose Tissue/drug effects , Anabolic Agents/administration & dosage , Animal Husbandry , Animals , Body Fat Distribution/veterinary , Body Weight/drug effects , Drug Combinations , Drug Implants , Estradiol/administration & dosage , Linear Models , Male , Meat/standards , Random Allocation , Time Factors , Trenbolone Acetate/administration & dosage , Trenbolone Acetate/pharmacology
16.
J Anim Sci ; 82(5): 1315-22, 2004 May.
Article in English | MEDLINE | ID: mdl-15144070

ABSTRACT

Angus steers of known age (265 +/- 17 d) and parentage were used in a 2-yr study (yr 1, n = 40; yr 2, n = 45) to evaluate the relationship between percentage of i.m. fat content of the longissimus dorsi at the 12th rib and carcass characteristics during growth of nonimplanted steers. Steers were sorted by age and EPD of paternal grandsire for marbling into high- and low-marbling groups so that steers with varying degrees of genetic potential for marbling were evenly distributed across slaughter groups. All steers were fed a 90% concentrate corn-based diet. Steers were allotted to five slaughter groups targeted to achieve hot carcass weights (HCW) of 204, 250, 295, 340, and 386 kg over the course of the feeding period. Data were analyzed as a completely random design with a factorial arrangement of treatments (year, marbling group, and slaughter group). Marbling group did not affect backfat, LM area, yield grade (YG), or marbling score. Regression equations were developed to quantify the change in carcass characteristics and composition over slaughter groups. Hot carcass weight increased in a linear fashion and differed (P < 0.01) among the slaughter groups as anticipated by design. Yield grade followed a quadratic upward pattern (P < 0.01) as HCW increased. Slaughter group affected the degree of marbling linearly (P < 0.01). There were no slaughter group x marbling group interactions, indicating that no differences occurred in the pattern of marbling attributable to paternal grandsire EPD. Carcasses expressed small degrees of marbling at 266 kg of HCW and obtained a YG of 3.0 at 291 kg of HCW. Fractional growth rates decelerated with increasing HCW. Greater advances in marbling relative to total carcass fatness occurred at HCW less than 300 kg. Management practices early in growth may influence final quality grade if compensatory i.m. fat content development does not occur.


Subject(s)
Adipose Tissue/growth & development , Body Composition/physiology , Cattle/growth & development , Muscle, Skeletal/anatomy & histology , Animals , Body Weight/physiology , Cattle/anatomy & histology , Factor Analysis, Statistical , Male , Meat/classification , Meat/standards , Muscle, Skeletal/growth & development , Random Allocation
17.
Pharm Dev Technol ; 6(3): 393-405, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11485181

ABSTRACT

PURPOSE: Studies were initiated to examine the effect of formulation and process variables on the delamination process and also the influence of the glass manufacturing process, supplier, and glass surface treatment. METHODS: Stress testing was performed by exposing filled vials to multiple sterilization cycles followed by accelerated stability testing. Delamination incidence was determined by visual examination, light obscuration (HIAC), and microscopical methods. The inner surface of vials from each supplier and lot were also examined by scanning electron microscopy. RESULTS: Vials sourced from Supplier A had smooth surfaces as demonstrated by SEM examination, whereas vials sourced from Suppliers B and C displayed extensive surface imperfections such as pitting and/or deposits. These imperfections were localized to the vial wall, adjacent to the vial bottom, and increased with sulfate treatment. Delamination incidence increased in those vial lots with increased surface imperfections. Thus, vials sourced from Supplier A had the lowest frequency of delamination. Sulfate treatment and high pH increased delamination incidence to as high as 100%. CONCLUSION: These results demonstrate the importance of the surface morphology created during the vial forming process. Given the diferences observed, final vial selection should include extensive microscopical and product stress testing studies on multiple vial lots.


Subject(s)
Chemistry, Pharmaceutical/methods , Cytosine/analogs & derivatives , Glass/chemistry , Infusions, Parenteral/instrumentation , Organophosphonates , Antineoplastic Agents/chemistry , Cidofovir , Cytosine/administration & dosage , Cytosine/chemistry , Disinfection , Drug Stability , Microscopy, Electron, Scanning , Organophosphorus Compounds/administration & dosage , Organophosphorus Compounds/chemistry , Pharmaceutical Solutions/chemistry , Sterilization , Stress, Mechanical , Surface Properties
18.
Acta Crystallogr C ; 57(Pt 8): 970-2, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11498630

ABSTRACT

The title compound, N,N'-difluoro-N,N'-ethylenedi-p-toluenesulfonamide, C(16)H(18)F(2)N(2)O(4)S(2).CHCl(3), is a novel stable compound of the N-F class of reagents containing two R(2)N-F functionalities. The compound, as the chloroform solvate, is the first such bis(N-F) compound to be structurally characterized. It adopts a solid-state structure in which the two aromatic rings are antiperiplanar and a combination of weak C-H...F and C-H...O hydrogen bonds [distances and angles range from 3.265 (4) to 3.439 (4) A and 150 to 170 degrees, respectively] and pi-stacking between the rings of different molecules (separations of 3.717 and 3.926 A) results in a solid-state structure containing well defined channels in which CHCl(3) solvent molecules are located. The N-F distances are 1.428 (3) and 1.433 (3) A.


Subject(s)
Sulfonamides/chemical synthesis , Toluene/chemical synthesis , Chloroform , Crystallography, X-Ray , Hydrogen Bonding , Models, Molecular , Solvents , Sulfonamides/chemistry , Sulfonamides/pharmacology , Toluene/analogs & derivatives , Toluene/chemistry , Toluene/pharmacology
19.
Acta Crystallogr C ; 57(Pt 6): 672-3, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11408665

ABSTRACT

The title structure, [ZnBr2(C2H8N2)], is made up of infinite -ZnBr2-(en)-ZnBr2-(en)- zigzag chains. Each repeat unit contains a trans ethylenediamine ligand [N-C-C-N -179 (1) degrees ], which bridges two approximately tetrahedral but crystallographically distinct Zn atoms. One Zn atom is bisected by a crystallographic twofold axis, whereas the other has mirror symmetry. Even though the crystal packing does not allow significant interaction between Zn and N atoms on adjacent chains, it does facilitate extensive intermolecular N-H...Br hydrogen bonding (N...H 2.69-2.96 A).

20.
Bioorg Med Chem Lett ; 11(3): 429-31, 2001 Feb 12.
Article in English | MEDLINE | ID: mdl-11212128

ABSTRACT

Two series of cytotoxic (IC50, K562 cell line, 1-24 microM) alpha-aminomethyl substituted lactones 3 and 4 were prepared by stereoselective Michael-type addition of amines to alantolactone (1) and isoalantolactone (2). The lactones 1 and 2 and their amine adducts induce apoptosis and act as alkylating agents.


Subject(s)
Amines/chemistry , Antineoplastic Agents/chemical synthesis , Lactones/pharmacology , Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Cell Cycle/drug effects , Cell Division/drug effects , Combinatorial Chemistry Techniques , Humans , Inhibitory Concentration 50 , K562 Cells , Lactones/chemical synthesis , Structure-Activity Relationship , Tumor Cells, Cultured/drug effects
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