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1.
Public Health ; 218: 121-127, 2023 May.
Article in English | MEDLINE | ID: mdl-37019027

ABSTRACT

OBJECTIVES: Since the Landmark Shelby V. Holder Supreme Court Ruling, the number of laws in the United States that make it difficult to vote has increased dramatically. This may lead to legislation that limits access to health care, including options for family planning services. We determine whether voting restrictions are associated with county-level teenage birth rates. STUDY DESIGN: This is an ecological study. METHODS: The Cost of Voting Index, a state-level measure of barriers to voting during US elections from 1996 to 2016, was used as a proxy for access to voting. County-level teenage birth rates were obtained from the County Health Rankings data. We used multilevel modeling to determine whether restrictive voting laws were associated with county-level teenage birth rates. We tested whether associations varied across racial and socio-economic groups. RESULTS: When confounders were included, a significant association was observed between increasing voting restrictions and teenage birth rates (ß = 1.72, 95% confidence interval: 0.54, 2.89). A Cost of Voting Index-median income interaction term was tested and was statistically significant (ß = -1.00, 95% confidence interval: -1.36, -0.64), indicating that the observed relationship was particularly strong among lower-income counties. The number of reproductive health clinics per capita within each state is a potential mediator. CONCLUSION: Restrictive voting laws were associated with higher teenage birth rates, particularly for low-income counties. Future work should use methods in which a causal relation can be identified.


Subject(s)
Birth Rate , Income , Adolescent , Humans , United States/epidemiology , Family Planning Services , Health Inequities , Politics
2.
Prev Sci ; 24(7): 1314-1326, 2023 10.
Article in English | MEDLINE | ID: mdl-36884129

ABSTRACT

There is increasing interest about the fidelity with which interventions are implemented because it is theorized that better implementation fidelity by facilitators is associated with better participant outcomes. However, in the parenting program literature, there is mixed evidence on the relationship between implementation fidelity and outcomes. This paper provides a synthesis of the evidence on the relationship between facilitator delivery and outcomes in the parenting program literature. Following PRISMA guidelines, this paper synthesizes the results of a systematic review of studies on parenting programs aiming to reduce violence against children and child behavior problems. Specifically, it examines associations between observational measures of facilitator competent adherence and parent and child outcomes. A meta-analysis was not feasible due to study heterogeneity. As a result, Synthesis Without Meta-Analysis guidelines were followed. Searches in electronic databases, reference searching, forward citation tracking, and expert input identified 9653 articles. After screening using pre-specified criteria, 18 articles were included. The review found that most studies (n = 13) reported a statistically significant positive relationship with at least one parent or child outcome. However, eight studies reported inconsistent findings across outcomes, and four studies found no association with outcomes. The results suggest that better facilitator competent adherence is generally associated with positive parent and child outcomes. However, this finding is weakened by the methodological heterogeneity of included studies and due to the wide variety of ways in which studies conceptualized competent adherence-outcome relationships.


Subject(s)
Parenting , Parents , Child , Humans
3.
JACC Case Rep ; 3(1): 69-73, 2021 Jan.
Article in English | MEDLINE | ID: mdl-34317471

ABSTRACT

A patient with severe mitral regurgitation and chronic systolic heart failure taking inotropic support at home presents for transcatheter edge-to-edge mitral valve repair, complicated by torrential mitral regurgitation from damaged mitral leaflets requiring escalating mechanical circulatory support and ultimately expedited orthotopic heart transplantation. (Level of Difficulty: Intermediate.).

4.
J Biomech ; 46(7): 1225-30, 2013 Apr 26.
Article in English | MEDLINE | ID: mdl-23506642

ABSTRACT

We developed a novel testing system that allows quantification of joint loading and permits analysis of changes in total protein and PRG4 contents in joint fluid of intact knees in live mice. A sequence of 15 repeat, isometric muscular contractions of "low" intensity (less than 50% of the maximal isometric muscular force), and "high" intensity (greater than 55% of maximal) were applied repeatedly (up to five times with a 15 min rest between contractions) to the mouse knee. Increases in knee joint loading were accompanied with significant increases in total protein (p<0.0001) and PRG4 concentrations in the synovial fluid. Total protein and PRG4 concentrations decreased with repeated "high" intensity loading. However, the addition of cell secretion inhibitors to the knee prior to muscular loading resulted in PRG4 levels that remained below the detection limit for all loading conditions. These results suggest that changes in synovial fluid proteins and PRG4 concentrations upon joint loading are mediated by cells within the joint, and that these changes may be used as quantitative indicators for the intensity and duration of acute joint loading, and might serve as a powerful clinical tool to assess the effectiveness of rehabilitation and prevention exercise programs.


Subject(s)
Isotonic Contraction/physiology , Knee Joint/metabolism , Muscle, Skeletal/metabolism , Proteoglycans/metabolism , Synovial Fluid/metabolism , Animals , Knee Joint/cytology , Male , Mice , Mice, Inbred C57BL , Muscle, Skeletal/cytology , Synovial Fluid/cytology , Weight-Bearing/physiology
5.
Osteoarthritis Cartilage ; 21(3): 498-504, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23257245

ABSTRACT

OBJECTIVES: Alternative splicing and variable post-translational modifications result in proteoglycan 4 (PRG4) proteins with historically reported apparent molecular weights (Ma) ranging from 150 to 400 kDa. The objectives of this study were to (1) identify and determine the weight averaged molecular weights (M(W)'s) of PRG4 proteins purified from medium with transforming growth factor-beta 1 (TGF-ß1) conditioned by mature bovine articular cartilage explants and (2) to examine the effect of reduction and alkylation (RA) on PRG4. METHODS: Non-reduced (NR) and RA preparations of PRG4 were separated using high performance liquid chromatography-size-exclusion chromatography with an in-line multi-angle laser light scattering (MALLS) detector, which was used for absolute determination of PRG4 M(W). Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), immunoblotting, and tandem mass spectrometry (MS/MS) analysis were used to confirm the identity of separated proteins. RESULTS: Three putative PRG4 monomers, one with previously uncharacterized M(W), were identified in NR and RA PRG4 preparations of 239 (223,255), 379 (369,389), and 467 (433,501) kDa. Additionally ∼1 MDa putative PRG4 dimer was identified. Release of a ∼90 kDa PRG4 fragment was also observed on SDS-PAGE after RA. Western Blotting with anti-PRG4 antibodies detected immunoreactive bands with Ma similar to M(W) for all species and excised bands were confirmed to be PRG4 by MS/MS. CONCLUSIONS: A variety of monomeric PRG4 proteins and a disulfide-bonded dimer/multimer are secreted by chondrocytes in bovine cartilage explants. The observed decrease in M(W)'s of monomeric PRG4 species upon RA may be due to the release of post-translationally cleaved fragments. Further study of these species will provide insight into the PRG4 molecular structure and function relationship.


Subject(s)
Cartilage, Articular/metabolism , Chondrocytes/metabolism , Proteoglycans/chemistry , Alkylation , Animals , Blotting, Western , Cartilage, Articular/drug effects , Cattle , Chondrocytes/drug effects , Chromatography, Gel , Chromatography, High Pressure Liquid , Electrophoresis, Polyacrylamide Gel , Lasers , Light , Molecular Weight , Proteoglycans/metabolism , Stifle , Tandem Mass Spectrometry , Transforming Growth Factor beta1/pharmacology
6.
Curr Med Chem ; 19(29): 4913-28, 2012.
Article in English | MEDLINE | ID: mdl-22963629

ABSTRACT

New nano-scale drug carriers offer the possibility of increasing the therapeutic index of drug molecules by increasing their effectiveness, diminishing their toxicity against physiological tissues and achieving controlled therapeutic levels for a prolonged time. This review gives an overview of approaches to the development of these novel complex nanocarriers with emphasis on those involving dendrimers and related systems. The combination of two of more nano-sized units for producing an overall system with unique properties could be advantageous compared to more simple nanotechnology-based carriers. Recent advances in medicinal chemistry offer the possibility of exact tailoring of the properties of such complex systems which, in conjunction with full physicochemical characterization, may lead to novel and highly effective drug products. An assessment is given of the potential of systems such as chimeric advanced Drug Delivery nano Systems (chi-aDDnSs) for the delivery of drugs compared with conventional carriers. Rational synthesis of molecules that can act as modulators of the properties of chi-aDDnSs and may be the future in the design and development of nanocarriers, not only for the delivery of drug molecules but also for genetic material and imaging agents is sought.


Subject(s)
Biomedical Technology/methods , Dendrimers/chemistry , Nanotechnology/methods , Animals , Dendrimers/chemical synthesis , Drug Carriers/chemical synthesis , Drug Carriers/chemistry , Drug Delivery Systems/methods , Humans
7.
J Anal Toxicol ; 35(5): 294-301, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21619724

ABSTRACT

Zolpidem, a Schedule IV controlled substance under the Federal Controlled Substance Act, has a rapid onset of action and short elimination half-life, rendering it ideal as a sleep aid. The crossreactivity of two zolpidem ELISA kits was investigated using patients taking a known administration of zolpidem. Subjects provided urine samples before, 30 min after their prescribed dose, and upon waking. Specimens were screened for zolpidem by ELISA (Immunalysis and Neogen) and then confirmed and quantitated for zolpidem using gas chromatography-mass spectrometry (GC-MS) confirmation in select ion monitoring mode. All samples were measured for creatinine and corrected accordingly. The ELISA screening results demonstrated that all samples, except one, screened positive by ELISA using both kits, even when the GC-MS data found no zolpidem in the patient's urine sample. The maximum concentrations of zolpidem ranged from 15 to 120 ng/mg creatinine. Two of the patients showed zolpidem concentrations of 10 ng/mg creatinine or above after 20 h post dose. The high variability and concentration range seen in these patients, all on similar doses, suggest wide variability in the metabolism of zolpidem.


Subject(s)
Hypnotics and Sedatives/urine , Pyridines/urine , Adolescent , Adult , Creatinine/metabolism , Cross Reactions , Enzyme-Linked Immunosorbent Assay , Female , Gas Chromatography-Mass Spectrometry , Half-Life , Humans , Hypnotics and Sedatives/chemistry , Male , Middle Aged , Pyridines/chemistry , Substance Abuse Detection/methods , Young Adult , Zolpidem
8.
Neuroendocrinology ; 92(3): 178-88, 2010.
Article in English | MEDLINE | ID: mdl-20714118

ABSTRACT

Kisspeptin, a regulator of gonadotropin-releasing hormone, has been hypothesized as an integrator of nutrition and hormones critical to metabolism and the regulation of reproduction. Growth hormone (GH) is necessary for optimal reproduction and recent evidence suggests that its secretion may be influenced by kisspeptin. The objectives of this study were to determine whether the effect of kisspeptin to stimulate GH release is due to an interaction with growth hormone-releasing hormone (GHRH) or somatostatin (SS), or an effect at the hypothalamus. Intravenous injection and infusion of kisspeptin [500 pmol/kg BW (650 ng/kg)/h × 5 h] to cows (n = 5) increased serum concentrations of luteinizing hormone (LH) but not GH. Pretreatment with kisspeptin injection and infusion in cows (n = 5) reduced the stimulatory effect of GHRH (0.05 µg/kg BW) on GH secretion. However, the magnitude of the GH response to GHRH (assessed by incremental AUC) was not affected by kisspeptin. In these same cows, administration of kisspeptin prevented the increase in GH induced by SS infusion (0.5 µg/kg BW/ h × 1.5 h) withdrawal. Peripheral administration of kisspeptin [200 and 1,000 pmol/kg BW (260 and 1,300 ng/kg)] increased serum concentrations of LH but not GH in ewes (n = 8). However, concentrations of GH were stimulated by central kisspeptin treatment [100 and 200 pmol/kg BW (130 and 260 ng/kg)] in ewes. In addition to activating the gonadotropic axis, kisspeptin can activate the somatotropic axis in ruminants. Present data support the concept of a central site of action for this effect.


Subject(s)
Growth Hormone/blood , Pituitary Gland, Anterior/metabolism , Tumor Suppressor Proteins/metabolism , Animals , Area Under Curve , Cattle , Female , Gonadotropin-Releasing Hormone/administration & dosage , Gonadotropin-Releasing Hormone/metabolism , Growth Hormone/metabolism , Kisspeptins , Luteinizing Hormone/blood , Ovariectomy , Pituitary Gland, Anterior/drug effects , Radioimmunoassay , Sheep , Somatostatin/administration & dosage , Tumor Suppressor Proteins/administration & dosage
9.
J Thromb Haemost ; 7(6): 1019-28, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19548909

ABSTRACT

BACKGROUND: Microparticles (MPs), small vesicles shed from stimulated cells, permit cross-talk between cells within a particular environment. Their composition is thought to reflect their cell of origin, and differs according to whether they are produced by stimulation or by apoptosis. Whether MP properties vary according to stimulus is not yet known. METHODS: We studied the characteristics of MPs produced from monocytic THP-1 cells upon stimulation with lipopolysaccharide or a soluble P-selectin chimera, using proteomics, flow cytometry, western blotting, and electron microscopy. RESULTS: Utilizing a novel criterion of calcein-AM staining to define MPs, we found that MP populations were similar with respect to size, presence and organization of cytoskeleton, and expression of certain antigens. The MPs shared the same level of procoagulant activity. We found that MPs also have distinct characteristics, depending on stimuli. These include differences in phosphatidylserine expression and expression of proteins from specific subcellular locations such as the mitochondria, and of unique antigens such as leukocyte-associated immunoglobin-like-receptor (LAIR)-1, which was found only upon stimulation with the soluble P-selectin chimera. CONCLUSION: We found that the properties of MPs depend on the stimulus that produced them. This supports the concept that monocytic MPs differentially modulate thrombosis, inflammation and immune regulation according to stimulus.


Subject(s)
Monocytes/immunology , Blotting, Western , Cell Line , Flow Cytometry , Humans , Microscopy, Electron , Particle Size , Proteomics
10.
Glob Public Health ; 4(2): 183-204, 2009.
Article in English | MEDLINE | ID: mdl-19333808

ABSTRACT

This paper assesses whether a nation-state's participation in conflict influences its ability to confront global pandemic or disease. Two alternative hypotheses are proposed. First, increased levels of conflict participation lead to increased abilities of states to confront pandemics. A second and alternative hypothesis is that increased conflict participation decreases the ability of states to confront pandemics. The hypotheses are tested through the ultimate case of war and pandemic: the 1918 Influenza pandemic (Spanish Flu or 'La Grippe') that killed 20-100 million people worldwide. Using simple correlation and case illustrations, we test these hypotheses with special focus upon the ability of the participant countries to confront the pandemic. The findings suggest, in a limited and varied fashion, that while neutral countries enjoyed the lowest levels of pandemic deaths, of the participant countries greater levels of conflict participation correlate with lower levels of pandemic deaths. The paper concludes with some propositions regarding the relationship between the current 'war on terror' and prospective pandemics such as avian flu.


Subject(s)
Disaster Planning , Disease Outbreaks , Influenza, Human/epidemiology , Warfare , History, 20th Century , Humans , Influenza, Human/history , Military Personnel , World War I
11.
Osteoporos Int ; 20(8): 1353-62, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19066707

ABSTRACT

SUMMARY: Recent evidence has linked long-term bisphosphonate use with insufficiency fractures of the femur in postmenopausal women. In this case-control study, we have identified a significant association between a unique fracture of the femoral shaft, a transverse fracture in an area of thickened cortices, and long-term bisphosphonate use. Further studies are warranted. INTRODUCTION: Although clinical trials confirm the anti-fracture efficacy of bisphosphonates over 3-5 years, the long-term effects of bisphosphonate use on bone metabolism are unknown. Femoral insufficiency fractures in patients on prolonged treatment have been reported. METHODS: We performed a retrospective case-control study of postmenopausal women who presented with low-energy femoral fractures from 2000 to 2007. Forty-one subtrochanteric and femoral shaft fracture cases were identified and matched by age, race, and body mass index to one intertrochanteric and femoral neck fracture each. RESULTS: Bisphosphonate use was observed in 15 of the 41 subtrochanteric/shaft cases, compared to nine of the 82 intertrochanteric/femoral neck controls (Mantel-Haenszel odds ratio (OR), 4.44 [95% confidence interval (CI) 1.77-11.35]; P = 0.002). A common X-ray pattern was identified in ten of the 15 subtrochanteric/shaft cases on a bisphosphonate. This X-ray pattern was highly associated with bisphosphonate use (OR, 15.33 [95% CI 3.06-76.90]; P < 0.001). Duration of bisphosphonate use was longer in subtrochanteric/shaft cases compared to both hip fracture controls groups (P = 0.001). CONCLUSIONS: We found a significantly greater proportion of patients with subtrochanteric/shaft fractures to be on long-term bisphosphonates than intertrochanteric/femoral neck fractures. Bisphosphonate use was highly associated with a unique X-ray pattern. Further studies are warranted.


Subject(s)
Bone Density Conservation Agents/adverse effects , Diphosphonates/adverse effects , Femoral Fractures/chemically induced , Aged , Aged, 80 and over , Body Mass Index , Bone Density Conservation Agents/administration & dosage , Case-Control Studies , Diphosphonates/administration & dosage , Drug Administration Schedule , Female , Femoral Fractures/diagnostic imaging , Femoral Fractures/etiology , Femoral Neck Fractures/chemically induced , Femoral Neck Fractures/etiology , Humans , Osteoporosis, Postmenopausal/complications , Osteoporosis, Postmenopausal/drug therapy , Radiography
12.
J Anal Toxicol ; 32(8): 688-94, 2008 Oct.
Article in English | MEDLINE | ID: mdl-19007522

ABSTRACT

In 1993, Zolpidem (Ambien), a non-benzodiazepine hypnotic agent, was approved for use in the United States for the short-term treatment of insomnia. Zolpidem has a rapid onset of action and short elimination half-life, rendering it ideal as a sleep aid. The objective of this study was to evaluate, and retrospectively compare, the use of the Immunalysis ELISA kit and gas chromatograpy-mass spectrometry (GC-MS) to screen blood/urine specimens for zolpidem. In addition, results for the incidence of zolpidem in suspected DUI drivers in 2007 are compared to previous years' data. The ELISA kit was evaluated for cross-reactivity with zaleplon and zopiclone and zolpidem metabolite I. Urine samples (n = 100) and blood samples (n = 100) were selected from specimens received into the DUI laboratory in 2007 and were screened via the Immunalysis Zolpidem ELISA kit and on GC-MS in full EI scan mode following an alkaline liquid-liquid extraction. Results show 5% of the urine and blood samples screened positive for zolpidem using the ELISA kits, and all 5% confirmed positive for zolpidem using GC-MS. The ELISA kit demonstrated no cross-reactivity to zaleplon or zopiclone at a spiked urine concentration of 1000 ng/mL. Ten cases of suspected DUI drivers in 2007 confirmed positive for zolpidem by ELISA and GC-MS in blood/urine, a higher incidence rate than in the previous years. Because of the low percentage elimination of the parent compound in urine, a screening method for the detection of the main metabolite of zolpidem may be needed for better detection of drug impairment driving due to zolpidem.


Subject(s)
Automobile Driving , Enzyme-Linked Immunosorbent Assay/methods , Gas Chromatography-Mass Spectrometry/methods , Hypnotics and Sedatives/analysis , Pyridines/analysis , Reagent Kits, Diagnostic , Substance Abuse Detection/methods , Female , Humans , Male , Pyridines/blood , Pyridines/urine , Retrospective Studies , Zolpidem
13.
J Anim Sci ; 86(10): 2557-67, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18502874

ABSTRACT

Melanocortin-4 receptors (MC4R) are key factors in the depression of appetite during disease. This study was designed to determine the role of agouti-related protein (AgRP) in the effect of endotoxin (lipopolysaccharide, LPS) on appetite. Sheep received an intracerebroventricular injection of either saline or AgRP (0.5 nmol/kg of BW) 1 h before intravenous injection of either saline or LPS (0.6 microg/kg of BW) at time 0 and again at 4 h. Agouti-related protein prevented the reduction in feed intake due to LPS (P < 0.05). In a second experiment, AgRP gene expression was unaffected at 3 h and increased (P < 0.01) at 6 h after LPS. Immunohistochemical evidence indicated that there was an increase in the percentage of AgRP neurons with c-Fos immunoreactive nuclei 6 h after sheep were injected with LPS (P < 0.04) and a corresponding decrease in a-melanocyte-stimulating hormone neurons coexpressing c-Fos (P < 0.001). In situ hybridization provided evidence for an increase in AgRP gene expression and a decrease in proopiomelanocortin gene expression 6 h after LPS (P < 0.05). In a final experiment, physiological elevation of orexigenic agents by short-term fasting kept feed intake at the same level as controls, in spite of the presence of LPS, similar to the effects of AgRP in Exp. 1. The AgRP inhibition of the MC4R prevents appetite inhibition in response to LPS and well after LPS inhibition of feed intake, both AgRP and a-melanocyte-stimulating hormone may change in a pattern that favors appetite increases. These studies support the notion of the MC4R as a critical component of the mechanism for appetite suppression due to endotoxin.


Subject(s)
Appetite/drug effects , Appetite/physiology , Lipopolysaccharides/pharmacology , Receptor, Melanocortin, Type 4/metabolism , Sheep/physiology , Agouti-Related Protein/administration & dosage , Agouti-Related Protein/genetics , Agouti-Related Protein/pharmacology , Animals , Body Temperature , Brain/metabolism , Cross-Over Studies , Food Deprivation , Injections, Intraventricular/veterinary , Lipopolysaccharides/administration & dosage , Male , Random Allocation , Receptor, Melanocortin, Type 4/antagonists & inhibitors
14.
Domest Anim Endocrinol ; 33(4): 390-9, 2007 Nov.
Article in English | MEDLINE | ID: mdl-17029675

ABSTRACT

The present research was conducted to model potential mechanisms through which IGFBPs might be affected by a key proinflammatory response initiating cytokine tumor necrosis factor (TNF-)-alpha. Madin-Darby bovine kidney epithelial (MDBK) cells, known to release IGFBPs in response to several stimuli, were grown under several conditions and challenged with forskolin (F) or recombinant TNF-alpha for 24h. Forskolin increased IGFBP-3 gene expression and media content of BP-3 protein. TNF-alpha increased basal and augmented F-mediated IGFBP-3 gene expression. However, TNF-alpha effects on the measurable media content of IGFBPs were influenced by culture conditions; in the absence of added protease inhibitors (PIs) or sufficient media albumin concentration (high BSA, 1mg/ml), the effect of TNF-alpha was to decrease (P<0.02) measurable IGFBPs. In the presence of PI and high BSA, media IGFBP-3 levels were shown to be increased by TNF-alpha consistent with the gene expression data. Changes in media IGFBP-3 protease activity were examined further to explain the observed effects of TNF-alpha on production and destruction of IGFBPs in media. When recombinant human IGFBP-3 (500 ng/ml) was added to PI-free, low BSA 100 microg/ml) media from TNF-treated MDBK cells, less than 10% of the BP-3 was recognizable by Western blot in 30 min; conversely, inclusion of High BSA and PI in media resulted in attenuation of the protease effect on the IGFBPs. The data suggest that the MDBK model of cellular response to proinflammatory stimulus is affected by culture conditions and that TNF-alpha affects media content of IGFBPs through effects on IGFBP gene expression coupled with degradation of IGFBPs via enhanced proteolytic enzyme release.


Subject(s)
Insulin-Like Growth Factor Binding Proteins/metabolism , Kidney/metabolism , Tumor Necrosis Factor-alpha/pharmacology , Animals , Cattle , Cell Line , Gene Expression/drug effects , Humans , Insulin-Like Growth Factor Binding Protein 2/genetics , Insulin-Like Growth Factor Binding Protein 3/genetics , Insulin-Like Growth Factor Binding Proteins/genetics , Kidney/drug effects , Recombinant Proteins
15.
J Anim Sci ; 85(1): 111-7, 2007 Jan.
Article in English | MEDLINE | ID: mdl-17179546

ABSTRACT

These experiments were conducted to determine if 1) syndyphalin-33 (SD33), a mu-opioid receptor ligand, affects feed intake; 2) SD33 effects on feed intake are mediated by actions on opioid receptors; and 3) its activity can counteract the reduction in feed intake associated with administration of bacterial endotoxin. In Exp. 1, 5 mixed-breed, castrate male sheep were housed indoors in individual pens. Animals had ad libitum access to water and concentrate feed. Saline (SAL; 0.9% NaCl) or SD33 (0.05 or 0.1 micromol/kg of BW) was injected i.v., and feed intake was determined at 2, 4, 6, 8, 24, and 48 h after the i.v. injections. Both doses of SD33 increased (at least P < 0.01) feed intake at 48 h relative to saline. In Exp. 2, SAL + SAL, SAL + SD33 (0.1 micromol/kg of BW), naloxone (NAL; 1 mg/kg of BW) + SAL, and NAL + SD33 were injected i.v. Food intake was determined as in Exp. 1. The SAL + SD33 treatment increased (P = 0.022) feed intake at 48 h relative to SAL + SAL. The NAL + SAL treatment reduced (at least P < 0.01) feed intake at 4, 6, 8, 24, and 48 h, whereas the combination of NAL and SD33 did not reduce feed intake at 24 (P = 0.969) or 48 h (P = 0.076) relative to the saline-treated sheep. In Exp. 3, sheep received 1 of 4 treatments: SAL + SAL, SAL + 0.1 micromol of SD33/kg of BW, 0.1 microg of lipopolysaccharide (LPS)/kg of BW + SAL, or LPS + SD33, and feed intake was monitored as in Exp. 1. Lipopolysaccharide suppressed cumulative feed intake for 48 h (P < 0.01) relative to saline control, but SD33 failed to reverse the reduction in feed intake during this period. These data indicate that SD33 increases feed intake in sheep after i.v. injection, and its effects are mediated via opioid receptors. However, the LPS-induced suppression in feed intake cannot be overcome by the opioid receptor ligand, SD33.


Subject(s)
Feeding Behavior/drug effects , Feeding Behavior/physiology , Receptors, Opioid/metabolism , Sheep/physiology , Animals , Bacteria/metabolism , Dose-Response Relationship, Drug , Lipopolysaccharides/toxicity , Male , Naloxone/pharmacology , Narcotic Antagonists/pharmacology , Oligopeptides/pharmacology
16.
Am J Physiol Endocrinol Metab ; 289(4): E650-7, 2005 Oct.
Article in English | MEDLINE | ID: mdl-15899940

ABSTRACT

In humans and sheep, endotoxin (LPS) administration results in increased growth hormone (GH) concentrations. To determine the role of cytokines in the effect of LPS on GH, sheep were challenged with IL-1beta or TNF-alpha. GH data were compared with results with LH, where the major effects of LPS are known to act via the hypothalamus. Intracerebroventricular (icv) administration of IL-1beta or TNF-alpha did not alter plasma concentrations of GH. Endotoxin was then administered intravenously (iv) in combination with icv injection of IL-1 receptor antagonist (IL-1RA), TNF antagonist (sTNF-R1), or saline. Administration of LPS increased GH (P < 0.0001), although coadministration of IL-1ra or sTNF-R1 icv did not alter GH response to LPS. In contrast, plasma concentrations of LH were profoundly inhibited by icv administration of either cytokine (P < 0.03), but the LH response to LPS was not altered by cytokine antagonists. Intravenous administration of either IL-1beta or TNF-alpha increased plasma concentrations of GH (P < 0.0001). Administration of IL-1RA and sTNF-R1 iv prevented LPS-induced increases in GH. Although LH was suppressed by high iv doses of IL-1beta (P = 0.0063), the antagonists did not alter the LH response to LPS. To determine whether LPS might directly activate GH release, confocal microscopy revealed colocalization of CD14, the LPS receptor, with GH and, to a lesser extent, LH and some prolactin (PRL)-containing cells, but not ACTH or TSH. These data are consistent with the effects of LPS on GH secretion originating through peripheral cytokine presentation to the pituitary, as well as a potential to act directly on selective populations of pituitary cells via CD14.


Subject(s)
Cytokines/blood , Growth Hormone/blood , Hypothalamus/metabolism , Interleukin-1/metabolism , Lipopolysaccharides/administration & dosage , Luteinizing Hormone/blood , Pituitary Gland/metabolism , Tumor Necrosis Factor-alpha/metabolism , Animals , Hypothalamus/drug effects , Male , Pituitary Gland/drug effects , Sheep
17.
Domest Anim Endocrinol ; 28(2): 224-32, 2005 Feb.
Article in English | MEDLINE | ID: mdl-15713369

ABSTRACT

Melanin-concentrating hormone (MCH) stimulates feeding when injected intracerebroventricularly (ICV) in rats. At present it is not clear whether the function of MCH is similar in ruminants, which are species with a continuous delivery of nutrients. Therefore the current investigation sought to determine the role of MCH in sheep. In the first experiment, six, castrate male sheep were satiated and received one of four treatments [saline, 0.1, or 1.0 nmol/kg MCH, and NPY (0.1 nmol/kg)] injected ICV over 30s, then infused ICV for 6 h ( approximately 500 microl/h). Food intake was measured for 2 h before and at 2, 4, 6, 8, 12 and 24 h. In this experiment, feed intake was increased (P

Subject(s)
Eating/drug effects , Hypothalamic Hormones/administration & dosage , Melanins/administration & dosage , Pituitary Hormones/administration & dosage , Sheep/physiology , Animals , Base Sequence , Eating/physiology , Food Deprivation/physiology , Hypothalamic Hormones/genetics , Hypothalamus/drug effects , Hypothalamus/metabolism , Immunohistochemistry/veterinary , Injections, Intraventricular/veterinary , Male , Melanins/genetics , Molecular Sequence Data , Neuropeptide Y/metabolism , Pituitary Hormones/genetics , RNA/chemistry , RNA/genetics , Random Allocation , Reverse Transcriptase Polymerase Chain Reaction/veterinary , Sequence Alignment , Sheep/metabolism
18.
Vet Microbiol ; 100(1-2): 31-41, 2004 May 20.
Article in English | MEDLINE | ID: mdl-15135511

ABSTRACT

Bartonella species are emerging pathogens that have been isolated worldwide from humans and other mammals. Our objective was to estimate the prevalence of Bartonella infection in free-ranging African lions (Panthera leo) and cheetahs (Acinonyx jubatus). Blood and/or serum samples were collected from a convenience sample of 113 lions and 74 cheetahs captured in Africa between 1982 and 2002. Whole blood samples available from 58 of the lions and 17 of the cheetahs were cultured for evidence of Bartonella spp., and whole blood from 54 of the 58 lions and 73 of the 74 cheetahs tested for the presence of Bartonella DNA by TaqMan PCR. Serum samples from the 113 lions and 74 cheetahs were tested for the presence of antibodies against Bartonella henselae using an immunofluorescence assay. Three (5.2%) of the 58 lions and one (5.9%) of the 17 cheetahs were bacteremic. Two lions were infected with B. henselae, based on PCR/RFLP of the citrate synthase gene. The third lion and the cheetah were infected with previously unidentified Bartonella strains. Twenty-three percent of the 73 cheetahs and 3.7% of the 54 lions tested by TaqMan PCR were positive for Bartonella spp. B. henselae antibody prevalence was 17% (19/113) for the lions and 31% (23/74) for the cheetahs. The prevalence of seropositivity, bacteremia, and positive TaqMan PCR was not significantly different between sexes and age categories (juvenile versus adult) for both lions and cheetahs. Domestic cats are thus no longer the only known carriers of Bartonella spp. in Africa. Translocation of B. henselae seronegative and TaqMan PCR negative wild felids might be effective in limiting the spread of Bartonella infection.


Subject(s)
Acinonyx/microbiology , Bartonella Infections/veterinary , Bartonella henselae/isolation & purification , Lions/microbiology , Africa, Eastern/epidemiology , Animals , Antibodies, Bacterial/blood , Bartonella Infections/microbiology , Bartonella henselae/genetics , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , Female , Fluorescent Antibody Technique , Male , Polymerase Chain Reaction/veterinary , Polymorphism, Restriction Fragment Length , Seroepidemiologic Studies , South Africa/epidemiology
19.
J Anim Sci ; 81(10): 2590-9, 2003 Oct.
Article in English | MEDLINE | ID: mdl-14552388

ABSTRACT

Four studies were designed to determine whether 1) tumor necrosis factor-alpha (TNF) and the Lipopolysaccharide (LPS) binding ligand, CD14, are produced by sheep adipose tissue; 2) nutritional reserves and/or short-term fasting affect circulating concentrations of TNF; 3) there is a relationship between TNF and metabolic factors in sheep; and 4) inflammation alters circulating concentrations of leptin. In Exp. 1 and 2, ewes were assigned, based on ultrasonic assessments of last-rib subcutaneous fat measurements to fat (fat thickness > 1 cm; mean = 1.52 +/- 0.03 cm) or thin (fat thickness < 1 cm; mean = 0.25 +/- 0.03 cm) groups. Fat and thin ewes were assigned to fed or fasted groups for a total of four groups (fed-fat; fasted-fat; fed-thin; fasted-thin). Fed-ewes had ad libitum access to feed, and fasted-ewes were prohibited feed 48 h before initiation of sample collection. In Exp. 1, subcutaneous fat samples were collected from just above the last rib for detection of TNF and CD14 mRNA, and immunoreactivity. Tumor necrosis factor-alpha-like immunoreactivity in adipocytes was sparse, more pronounced in cells in fed-ewes than fasted-ewes, and localized to membranes between adjacent cells in nucleated regions. Immunoreactivity for CD14 was minimally observed but present in adipocytes and widely expressed in infiltrating monocytes and epithelial vascular cells. Leptin was detected in adipocytes. In Exp. 2, plasma samples collected every 6 h for 24 h were analyzed for plasma concentrations of TNF. Fat ewes had greater plasma concentrations of TNF than thin ewes (P = 0.039). In Exp. 3, wethers were injected i.v. with interleukin-1beta or TNF. Blood samples were collected every 15 min for 8 h following injection. Plasma concentration of leptin was not affected by treatment (P > 0.39). In Exp. 4, wethers were injected with LPS. Blood samples were collected every 15 min for 8 h following injection. Plasma concentration of leptin was not altered by LPS (P > 0.20). These results provide evidence: 1) of TNF-like immunoreactivity within fat tissue; 2) that elements within fatty tissues have CD14 that may allow adipocyte function to be directly affected by LPS; 3) that plasma concentrations of leptin are not altered by LPS treatment; and 4) that circulating concentrations of TNF are elevated with obesity in sheep.


Subject(s)
Adipose Tissue/metabolism , Leptin/biosynthesis , Lipopolysaccharide Receptors/biosynthesis , Sheep/physiology , Tumor Necrosis Factor-alpha/biosynthesis , Adipose Tissue/physiology , Animals , Body Composition/physiology , Female , Food Deprivation/physiology , Leptin/blood , Lipopolysaccharide Receptors/blood , Lipopolysaccharides/pharmacology , Male , Nutritional Status , Sheep/blood , Tumor Necrosis Factor-alpha/metabolism
20.
J Anim Sci ; 81(6): 1546-51, 2003 Jun.
Article in English | MEDLINE | ID: mdl-12817503

ABSTRACT

Estradiol plus progesterone (EP) implants have been shown to favorably alter the time course or decrease the severity of many of the clinical manifestations associated with coccidiosis and endotoxemia in calves. This study evaluated the effect of EP treatment on plasma tumor necrosis factor-alpha (TNF), thromboxane (TXB), prostacyclin (PRC), nitrite and nitrate (NO[x]), and cortisol. Holstein steer calves were divided into four groups: control, EP, endotoxin (LPS), and EP + LPS (n = five/group). Estradiol/progesterone pellets (Synovex-S) were implanted subcutaneously when calves reached 20 wk of age. One week after implantation, calves were injected i.v. with endotoxin (i.e., lipopolysaccharide; LPS, 0.6 microgram/kg of BW) or nonpyrogenic saline placebo. Body temperature was measured and blood was collected before injection and at 1, 2, 3, 4, 6, and 8 h thereafter. Plasma concentrations of TNF, cortisol, TXB, PRC, NO[x], were measured. Body temperature increased in both LPS and LPS-EP calves, but had returned to normal by 6 h in the LPS-EP group (P < 0.05). Plasma TNF and cortisol increased after LPS (P < 0.01), but were not differentially affected by EP treatment. Likewise, EP did not affect the magnitude of increase in LPS-induced PRC, but EP decreased the magnitude of increase in TXB (P < 0.05). Plasma NO[x]) levels were increased (P < 0.01) in calves after LPS; treatment with EP attenuated the LPS-associated increase in plasma NO[x] levels. These results suggest that EP exerts specific effects on different components of the proinflammatory cytokine cascade. Although the initiation of responses mediated by TNF, cortisol, and PRC do not seem to be differentially affected by EP, components of the nitric oxide- and TXB-axis responses to LPS are decreased in calves pretreated with EP.


Subject(s)
Cattle Diseases/immunology , Endotoxemia/veterinary , Estradiol/pharmacology , Nitric Oxide/biosynthesis , Progesterone/pharmacology , Thromboxane B2/biosynthesis , Animal Feed/toxicity , Animals , Cattle , Cattle Diseases/drug therapy , Cytokines/biosynthesis , Cytokines/immunology , Endotoxemia/drug therapy , Endotoxemia/immunology , Lipopolysaccharides/toxicity , Male , Random Allocation , Tumor Necrosis Factor-alpha/analysis
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