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The problem of over-medicalisation: How AOD disease models perpetuate inequity for young people with multiple disadvantage. THE INTERNATIONAL JOURNAL OF DRUG POLICY 2022; 103:103631. [PMID: 35276402 DOI: 10.1016/j.drugpo.2022.103631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 02/15/2022] [Accepted: 02/18/2022] [Indexed: 11/30/2022]
Abstract
Young people who experience multiple disadvantage have been identified as some of the most marginalised and under-serviced people in the alcohol and other drug (AOD) system. In this paper, we draw on a range of research evidence to argue that one of the challenges in responding appropriately to the needs of these young people are models of care which seek to ameliorate 'illness' rather than promote wellness. While disease approaches have some important benefits, overly-medicalised AOD treatment responses also have negative impacts. We argue that disease models rest on understandings of substance use as an individual enterprise and thereby pay insufficient attention to the material disadvantage that shape young people's substance use, creating feelings of shame, failure and a reluctance to return to care if they continue to use. Additionally we draw on literature that shows how disease models construe young people's substance use as compulsive, perpetuating deficit views of them as irrational and failing to account for the specific meanings that young people themselves give to their substance use. By focusing on clinical solutions rather than material and relational ones, medicalised treatment responses perpetuate inequity: they benefit young people whose resources and normative values align with the treatments offered by disease models, but are much less helpful to those who are under-resourced,. We suggest that alternative approaches can be found in First Nations models of care and youth programs that attend to social, cultural, and material wellbeing, making living well the focus of treatment rather than illness amelioration.
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Excreta emissions in progeny of low and high enteric methane yield selection line sheep fed pasture of different qualities. Anim Feed Sci Technol 2019. [DOI: 10.1016/j.anifeedsci.2019.114289] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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3
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Development of a recombinant murine tumour model using hepatoma cells expressing hepatitis C virus nonstructural antigens. J Viral Hepat 2018; 25:649-660. [PMID: 29316037 DOI: 10.1111/jvh.12856] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Accepted: 12/14/2017] [Indexed: 12/14/2022]
Abstract
Hepatitis C virus (HCV) chronically infects 2%-3% of the world's population, causing liver disease and cancer with prolonged infection. The narrow host range of the virus, being restricted largely to human hepatocytes, has made the development of relevant models to evaluate the efficacy of vaccines a challenge. We have developed a novel approach to accomplish this by generating a murine hepatoma cell line stably expressing nonstructural HCV antigens which can be used in vitro or in vivo to test HCV vaccine efficacies. These HCV-recombinant hepatoma cells formed large solid-mass tumours when implanted into syngeneic mice, allowing us to test candidate HCV vaccines to demonstrate the development of an HCV-specific immune response that limited tumour growth. Using this model, we tested the therapeutic potential of recombinant anti-HCV-specific vaccines based on two fundamentally different attenuated pathogen vaccine systems-attenuated Salmonella and recombinant adenoviral vector based vaccine. While attenuated Salmonella that secreted HCV antigens limited growth of the HCV-recombinant tumours when used in a therapeutic vaccination trial, replication-competent but noninfectious adenovirus expressing nonstructural HCV antigens showed overall greater survival and reduced weight loss compared to non-replicating nondisseminating adenovirus. Our results demonstrate a model with anti-tumour responses to HCV nonstructural (NS) protein antigens and suggest that recombinant vaccine vectors should be explored as a therapeutic strategy for controlling HCV and HCV-associated cancers.
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Sheep from low-methane-yield selection lines created on alfalfa pellets also have lower methane yield under pastoral farming conditions. J Anim Sci 2018; 95:3905-3913. [PMID: 28991992 DOI: 10.2527/jas2017.1709] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Selection lines of sheep with low and high CH yield (g/kg DMI; CH/DMI) are being developed on the basis of feeding pelleted alfalfa hay at 2.0 times maintenance ME requirements in respiration chambers, but their divergence under predominant grazing conditions, as in New Zealand, is not known. The objectives of this study were to determine CH emissions and rumen fermentation characteristics in sheep from low and high CH/DMI selection lines while grazing pasture. Two grazing experiments were conducted with 42 selection line ewes in March 2013 (Exp. 1) and 98 selection line progeny ewe hoggets in October/November 2014 (Exp. 2), with CH emissions estimated by the SF tracer technique and DMI estimated by titanium oxide in combination with natural long-chain -alkanes. Total daily CH production (g/d) was similar between high and low CH/DMI selection line sheep in Exp. 1 and lower for low CH/DMI progeny compared with high CH/DMI progeny in Exp. 2 ( < 0.05). The CH/DMI tended to be 20% lower for low CH/DMI line sheep compared with high CH/DMI selection line sheep in Exp. 1 ( < 0.10) and was 15% lower for the low CH/DMI line in Exp. 2 ( < 0.01). Total VFA concentration and concentrations (m) of acetate, butyrate, and isobutyrate plus isovalerate were lower ( < 0.05) for low CH/DMI line sheep compared with high CH/DMI selection line sheep in both experiments. The current study indicates that differences in CH/DMI and VFA concentrations in selection line sheep, previously established on alfalfa pellets, are also present to a similar magnitude when grazing pasture.
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Sheep from low-methane-yield selection lines created on alfalfa pellets also have lower methane yield under pastoral farming conditions1,2. J Anim Sci 2017. [DOI: 10.2527/jas.2017.1709] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
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Event-related brain potentials during the visuomotor mental rotation task: The contingent negative variation scales to angle of rotation. Neuroscience 2015; 311:153-65. [PMID: 26477986 DOI: 10.1016/j.neuroscience.2015.10.018] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Revised: 10/07/2015] [Accepted: 10/09/2015] [Indexed: 11/16/2022]
Abstract
Perceptual judgments about the angular disparity of a character from its standard upright (i.e., mental rotation task) result in a concurrent increase in reaction time (RT) and modulation of the amplitude of the P300 event-related brain potential (ERP). It has therefore been proposed that the P300 represents the neural processes associated with a visual rotation. In turn, the visuomotor mental rotation (VMR) task requires reaching to a location that deviates from a target by a predetermined angle. Although the VMR task exhibits a linear increase in RT with increasing oblique angles of rotation, work has not examined whether the task is supported via a visual rotation analogous to its mental rotation task counterpart. This represents a notable issue because seminal work involving non-human primates has ascribed VMR performance to the motor-related rotation of directionally tuned neurons in the primary motor cortex. Here we examined the concurrent behavioral and ERP characteristics of a standard reaching task and VMR tasks of 35°, 70°, and 105° of rotation. Results showed that the P300 amplitude was larger for the standard compared to each VMR task--an effect independent of the angle of rotation. In turn, the amplitude of the contingent negative variation (CNV)--an ERP related to cognitive and visuomotor integration for movement preparation--was systematically modulated with angle of rotation. Thus, we propose that the CNV represents an ERP correlate related to the cognitive and/or visuomotor transformation demands of increasing the angular separation between a stimulus and a movement goal.
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Abstract
Tuberculosis of bone is an uncommon entity in the Western world. We present a case of tuberculosis of the patella mimicking prepatellar bursitis in an otherwise fit and well woman of Bangladeshi origin. We believe tuberculosis of bone should form a differential diagnosis of the swollen knee in high risk patients.
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Tendon regeneration and repair with stem cells. Stem Cells Int 2011; 2012:316281. [PMID: 25098364 PMCID: PMC3205775 DOI: 10.1155/2012/316281] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2011] [Accepted: 09/05/2011] [Indexed: 01/08/2023] Open
Abstract
The use of stems cells in tendon repair is of particular interest given the frequency of tendon injuries worldwide together with the technical difficulty often encountered when repairing or augmenting tendons. Stems cells have the capability to differentiate into a variety of different cell types including osteocytes and tenocytes, and if normal architecture of damaged tendon (either macroscopic or microscopic) could be restored, this would significantly improve the management of patients with these injuries. There is already encouraging research on the use of stems cells clinically although considerable further work is required to improve knowledge and clinical applications of stem cells in tissue engineering.
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Assessment of the sulphur hexafluoride (SF6) tracer technique using respiration chambers for estimation of methane emissions from sheep. Anim Feed Sci Technol 2011. [DOI: 10.1016/j.anifeedsci.2011.04.067] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Comparison of lethal versus non-lethal sample sources for the detection of infectious salmon anemia virus (ISAV). DISEASES OF AQUATIC ORGANISMS 2005; 66:181-5. [PMID: 16261932 DOI: 10.3354/dao066181] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
The emergence of infectious salmon anemia virus (ISAV) in Canada and the USA has led to the establishment of ISAV surveillance programs for cultured Atlantic salmon (Salmo salar L.) and wild fish species, including Atlantic salmon. Current testing procedures for ISAV consist of viral culture, reverse-transcription polymerase chain reaction (RT-PCR) and indirect fluorescent antibody testing (IFAT), and require lethal sampling. As the focus of this study, blood was evaluated as a possible non-lethal sample source for ISAV diagnostic screening by viral culture and RT-PCR. Tissue samples (consisting of kidney/spleen for viral culture or kidney only for RT-PCR), blood and, to a lesser extent, mucus were tested from Atlantic salmon survivors of laboratory ISAV infection trials and moribund fish from marine salmon grow-out facilities participating in a USDA-sponsored surveillance program. The trial fish represented a potential carrier population, while the surveillance fish were composed of moribund individuals from ISA clinical sites. Sample sources and diagnostic techniques were compared. Blood compared well to tissue samples for viral culture and produced a greater number of positives than did kidney samples for ISAV detection by RT-PCR. RT-PCR using both kidney and blood samples was determined to be a more sensitive assay than viral isolation. Mucus did not perform well in either assay compared to the other sample sources. Blood appears to be a reliable non-lethal sample source for the detection of ISAV by viral culture and RT-PCR in both moribund and asymptomatic fish.
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Abstract
A combined segregation, linkage, and association analysis using the program COMBIN was performed on the simulated pedigree data prepared for the Second Genetic Analysis Workshop. The model used in COMBIN is described and the presented results illustrate its effectiveness in the analysis of such data. Linkage analysis was performed and maps for each linkage group are presented.
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Abstract
Arg-20 is one of two residues conserved in all peptides known to activate the parathyroid hormone (PTH) receptor. Previous studies have failed to find any naturally encoded analogues of residue 20 that had any adenylyl cyclase (AC) stimulating activity. In this work we have studied substitutions of Arg-20 with nonencoded amino acids and conformationally constrained analogues with side chains mimicking that of Arg. No analogue had more than 20% of the AC-stimulating ability of the natural Arg-20-bearing peptide. In descending order of activity, the most active analogues had (S)-4-piperidyl-(N-amidino)glycine (PipGly), norleucine (Nle), citrulline (Cit), or ornithine (Orn) at residue 20. Analogues with Arg-20 substituted with L-4-piperidyl-(N-amidino)alanine, Lys, Glu, Ala, Gln, (S)-2-amino-4-[(2-amino)pyrimidinyl]butanoic acid, or L-(4-guanidino)phenylalanine had very low or negligible activity. Low or negligible activities of Lys or Orn analogues suggested ionic interactions play a minor role in the Arg interaction with the receptor. The conformational constraints imposed by the PipGly ring had a negative effect on its ability to substitute for Arg. The side-chain H-bonding potential of the Cit ureimido group was likely an important factor in its mimicry of Arg. The increase in amphiphilicity, as demonstrated by its greater high-performance liquid chromatographic retention, and increased alpha-helix, as shown by circular dichroic spectroscopy, likely contributed to the activity of the Nle-20 analogue. The data demonstrated that specific H-bonding, hydrophobicity of the side chain, stabilization of alpha-helix, and possibly specific cation positioning were all important in the interaction of Arg-20 with receptor groups.
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The effect of monocyclic and bicyclic analogs of human parathyroid hormone (hPTH)-(1-31)NH2 on bone formation and mechanical strength in ovariectomized rats. Calcif Tissue Int 2001; 68:95-101. [PMID: 11310353 DOI: 10.1007/bf02678147] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The [Leu27]cyclo(Glu22-Lys26)-hPTH-(1-31)NH2 lactam is a stronger stimulator of adenylyl cyclase activity and a better stimulator of trabecular bone in the ovariectomized (OVX) rat model of osteopenia than hPTH-(1-31)NH2. This enhanced activity is due in large part to the stabilization of the amphiphilic receptor-binding alpha-helix in the Ser17-Gln29 region. The goal of the present study was to determine whether further cyclization could produce a more active hPTH analog. To this end, we compared the relative bioactivities of the bicyclic hPTH analog [Glu17,Leu27]cyclo(Lys13-Glu17,Glu22-Lys26)-hPTH-(1-31)NH2, made by replacing Ser17 with Glu17 and introducing a second lactam linkage between Lys13 and Glu17. The relative EC50 for adenylyl cyclase stimulation by the bicyclic hPTH analog was similar to the EC50 of the monocyclic [Leu27]cyclo(Glu22-Lys26)-hPTH-(1-31)NH2, but the bicyclic analog was still more active than hPTH-(1-31)NH2. As expected from adenylyl cyclase stimulation being responsible for PTH's anabolic action, the bicyclic hPTH analog [Glu17, Leu27]cyclo(Lys13-Glu17, Glu22-Lys26)-hPTH-(1-31)NH2 was able to increase femoral trabecular volume and thickness and mechanical strength in OVX rats, but it was no more effective than [Leu27]cyclo(Glu22-Lys26)-hPTH-(1-31)NH2 when injected once daily in a dose of 0.8 nmol/100 g body weight. Thus, further constraint of the conformation of hPTH-(1-31)NH2 by introducing two lactam link-ages between Lys13-Glu17 and Glu22-Lys26 did not raise the osteogenicity above that of the monocyclic analog.
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Structure and activities of constrained analogues of human parathyroid hormone and parathyroid hormone-related peptide: implications for receptor-activating conformations of the hormones. Biochemistry 2000; 39:14522-30. [PMID: 11087406 DOI: 10.1021/bi001527r] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Parathyroid hormone (PTH) has a helix-bend-helix structure in solution. Part of the C-terminal helix, residues 21-31, is amphiphilic and forms a critical receptor-binding region. Stabilization of this alpha-helix by lactam formation between residues spaced i, i + 4 on the polar face was previously reported to increase adenylyl cyclase-stimulating (AC) activity if between residues 22 and 26 but to diminish it if between residues 26 and 30 [Barbier et al. (1997) J. Med. Chem. 40, 1373-1380]. This work reports the effects of other cyclizations on the polar face, differing in ring size or position, on alpha-helix conformation, as measured by circular dichroism, and on AC-stimulating activity. All analogues cyclized between residues 22 and 26 had at least a 1. 5-fold increase in activity, suggesting an alpha-helical structure between about residues 21 and 26. Cyclization between residues 25 and 29 or residues 26 and 30 diminished activity by 20-30%, despite stabilizing alpha-helix, suggesting that residues 25-31 bind to the receptor in a helical, but not classical alpha-helical, conformation. Analogues cyclized between residues 13 and 17 had slightly increased activity. A bicyclic analogue, with lactams between residues 13 and 17 and residues 22 and 26, had about the same activity as that cyclized only between 22 and 26. Parathyroid hormone-related peptide (PTHrP) may bind in a manner similar to the common receptor, but hydrophobic moment calculations suggest that it must bind as a tighter helix in order to optimally present its hydrophobic residues to the receptor. Both PTHrP analogues cyclized between either residues 22 and 26 or residues 26 and 30 had more stable alpha-helices but reduced AC activities, consistent with this hypothesis.
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Internet connections. JOURNAL (CANADIAN DENTAL ASSOCIATION) 2000; 66:297. [PMID: 10960251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/15/2023]
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Pharmacological and molecular characterization of glutamate receptors in the MIN6 pancreatic beta-cell line. Neurol Res 2000; 22:379-85. [PMID: 10874687 DOI: 10.1080/01616412.2000.11740687] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
The MIN6 pancreatic beta-cell line responds to glutamate, alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) and kainate, but not N-methyl-D-aspartate (NMDA) or 1S,3R-trans-ACPD, with increases in [Ca2+]i. This correlates with MIN6 expression of AMPA receptor subunits (GluR1-4) but only weak expression of NMDA NR2 receptor subunits, as determined by reverse transcriptase polymerase chain reaction (RT-PCR). Pharmacological characterization of the MIN6 AMPA receptors showed that AMPA-triggered [Ca2+]i responses were blocked by GYKI 52466, 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) and pentobarbital. AMPA-triggered [Ca2+]i responses were also blocked in Na(+)-free medium and by the voltage-sensitive Ca2+ channel antagonist La3+. Unlike cortical neuronal cultures, which show a loss of membrane-associated protein kinase C (PKC) activity and die in response to excitatory amino acid exposure, glutamate was not toxic to MIN6 cells and it did not decrease PKC activity. These studies indicate that MIN6 cells possess Ca(2+)-impermeable AMPA receptors that secondarily allow Ca2+ influx following AMPA-induced depolarization and that, despite elevating [Ca2+]i, AMPA is not toxic to these cells. The effects of glutamate and glutamate receptor antagonists on pancreatic cells needs to be better understood if these compounds are to be used as therapeutic agents to treat stroke.
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Internet security. JOURNAL (CANADIAN DENTAL ASSOCIATION) 2000; 66:239. [PMID: 10833863] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
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Lactam formation increases receptor binding, adenylyl cyclase stimulation and bone growth stimulation by human parathyroid hormone (hPTH)(1-28)NH2. J Bone Miner Res 2000; 15:964-70. [PMID: 10804028 DOI: 10.1359/jbmr.2000.15.5.964] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Human parathyroid hormone (1-28)NH2 [hPTH(1-28)NH2] is the smallest of the PTH fragments that can fully stimulate adenylyl cyclase in ROS 17/2 rat osteoblast-like osteosarcoma cells. This fragment has an IC50 of 110 nM for displacing 125I-[Nle8,18,Tyr34]bovine PTH(1-34)NH2 from HKRK B7 porcine kidney cells, which stably express 950,000 human type 1 PTH/PTH-related protein (PTHrP) receptors (PTH1Rs) per cell. It also has an EC50 of 23.9 nM for stimulating adenylyl cyclase in ROS 17/2 cells. Increasing the amphiphilicity of the alpha-helix in the residue 17-28 region by replacing Lys27 with Leu and stabilizing the helix by forming a lactam between Glu22 and Lys26 to produce the [Leu27]cyclo(Glu22-Lys26)hPTH(1-28)NH2 analog dramatically reduced the IC50 for displacing 125I-[Nle8,18,Tyr34]bPTH(1-34)NH2 from hPTH1Rs from 110 to 6 nM and dropped the EC50 for adenylyl cyclase stimulation in ROS 17/2 cells from 23.9 to 9.6 nM. These modifications also increased the osteogenic potency of hPTH(1-28)NH2. Thus, hPTH(1-28)NH2 did not significantly stimulate either femoral or vertebral trabecular bone growth in rats when injected daily at a dose of 5 nmol/100 g body weight for 6 weeks, beginning 2 weeks after ovariectomy (OVX), but it strongly stimulated the growth of trabeculae in the cancellous bone of the distal femurs and L5 vertebrae when injected at 25 nmol/100 g body weight. By contrast [Leu27]cyclo(Glu22-Lys26)hPTH(1-28)NH2 significantly stimulated trabecular bone growth when injected at 5 nmol/100 g of body weight. Thus, these modifications have brought the bone anabolic potency of hPTH(1-28)NH2 considerably closer to the potencies of the larger PTH peptides and analogs.
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The stimulation of vertebral and tibial bone growth by the parathyroid hormone fragments, hPTH-(1-31)NH2, [Leu27]cyclo(Glu22-Lys26)hPTH-(1-31)NH2, and hPTH-(1-30)NH2. Calcif Tissue Int 2000; 66:307-12. [PMID: 10742450 DOI: 10.1007/s002230010061] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The native human parathyroid hormone, hPTH-(1-84), and certain carboxyl truncated analogs such as hPTH-(1-34) and even smaller fragments such as hPTH-(1-31)NH2, [Leu27]cyclo(Glu22-Lys26)hPTH-(1-31)NH2, and hPTH-(1-30)NH2 stimulate femoral trabecular and cortical bone growth in ovariectomized (OVX) rats. Here we show that when injected once daily for 6 weeks starting 2 weeks after OVX in doses of 1 or 2 nmol/100 g of body weight, hPTH-(1-31)NH2, [Leu27] cyclo(Glu22-Lys26)hPTH-(1-31)NH2, and hPTH-(1-34)NH2 prevented the loss of trabecular volume in the L5 vertebrae induced by OVX. In fact, by the end of the sixth week of injections (i.e., the eighth week after OVX) the fragments had increased the volume and trabecular thickness significantly above the values in vehicle-injected sham-operated rats. hPTH-(1-30)NH2 can stimulate vertebral bone growth as much as the larger fragments, but 10-25 times more of it was needed to do so. The same daily doses of hPTH-(1-31)NH2, [Leu27]cyclo(Glu22-Lys26)hPTH-(1-31)NH2, and hPTH-(1-34)NH2 also raised the trabecular volume and thickness in the L5 vertebrae of rats well above the values in vehicle-treated animals when the injections were started 9 weeks after OVX. This restoration of trabecular bone in the L5 vertebrae in estrogen-deprived animals was accompanied by a significant increase in the bone mineral density (BMD) of the L1-L4 vertebrae and tibias. However, there was no significant drop in the pelvic BMD in the estrogen-deprived animals and the effects of hPTH-(1-31)NH2, [Leu27]cyclo(Glu22-(Lys) hPTH-(1-31)NH2, and hPTH-(1-34)NH2 on the pelvic BMD were equivocal.
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E-mail. 20 reasons why you should have it in your dental office. DENTAL ASSISTANT (CHICAGO, ILL. : 1994) 2000; 69:6-8, 17. [PMID: 11218293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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Protocol for the dental office. JOURNAL (CANADIAN DENTAL ASSOCIATION) 2000; 66:76. [PMID: 10755842] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
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Educational sites on the Internet. JOURNAL (CANADIAN DENTAL ASSOCIATION) 1999; 65:607. [PMID: 10658387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/14/2023]
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Stimulation of femoral trabecular bone growth in ovariectomized rats by human parathyroid hormone (hPTH)-(1-30)NH(2). Calcif Tissue Int 1999; 65:143-7. [PMID: 10430648 DOI: 10.1007/s002239900673] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
It has been proposed that intermittent bursts of adenylyl cyclase and the surges of cyclic AMP (cAMP) they produce can trigger PTH's bone anabolic action without the activation of phospholipase-C (PLC). This was based on the osteogenic action in ovariectomized (OVX) rats of hPTH-(1-31)NH(2), which can stimulate adenylyl cyclase but not PLC in ROS 17/2 rat osteosarcoma cells, and the osteogenic impotence of fragments such as 1-desamino-hPTH-(1-34) and hPTH-(8-84) which strongly stimulate PLC but not adenylyl cyclase. But this seems to have been disproven by the inability of hPTH-(1-30)NH(2) to stimulate bone growth despite its having hPTH-(1-31)NH(2)'s ability to strongly stimulate adenylyl cyclase but not PLC in cells with rat type1 PTH/PTHrP receptors. Because of the importance of hPTH-(1-30)NH(2)'s apparent osteogenic impotence for knowing how PTH triggers bone growth, we have reinvestigated the fragment's ability to stimulate trabecular bone growth in the femurs of young OVX rats and have found it to be strongly osteogenic at doses 2-10 times higher than the highest dose used previously. Thus, 6 weeks of once-daily subcutaneous injections of 10-50 nmol of hPTH-(1-30)NH(2)/100 g of body weight into young rats starting 2 weeks after OVX significantly increased the femoral trabecular volume and mean thickness of individual trabeculae above those in sham-operated control rats. In OVX rats treated with 50 nmol of hPTH-(1-30)NH(2)/100 g of body weight, the trabecular volume was 2.6 times higher and the mean trabecular thickness nearly 4 times higher than in the sham-operated control rats. This very large increase in the mean trabecular thickness was as much as the increase induced by 2 nmol/100 g of body weight of hPTH-(1-31)NH(2), [Leu(27)]cyclo(Glu(22)-Lys(26))-hPTH-(1-31)NH(2), hPTH-(1-34)NH(2) and [Leu(27)]cyclo(Glu(22)-Lys(26))-hPTH-(1-34)NH(2). These results have removed a major objection to the proposal that PTH's osteogenic action in rats can be triggered solely by intermittent surges of cAMP and the bursts of cAMP-dependent protein kinase activity they cause.
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Prolonged low-dose infusion of human parathyroid hormone does not increase femoral cancellous bone volume in ovariectomized rats. Eur J Endocrinol 1999; 141:70-4. [PMID: 10407226 DOI: 10.1530/eje.0.1410070] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVE Daily injections of human parathyroid hormone (hPTH) increase bone volume in various animal species and in osteoporotic women. For hPTH to be widely accepted as an anabolic therapy for treating postmenopausal osteoporosis alternative delivery options need to be explored to replace the need for daily patient subcutaneous self-injection. Among these are inhalation, oral delivery and the use of programmable implanted minipumps to deliver the peptide. While infusion of high doses of PTH causes bone loss and hypercalcemia, no studies have assessed the effects of prolonged infusion of low doses of PTH on bone growth. DESIGN AND METHODS [Leu(27)]-cyclo(Glu(22)-Lys(26))-hPTH-(1--31)NH(2) was delivered by Alzet minipumps to ovariectomized rats for 6 weeks after which histomorphometric indices (cancellous bone volume, trabecular thickness, mean trabecular number) of bone formation were measured in distal femurs. RESULTS Infusing low doses (0.05 and 0.1 nmole/100g body weight/day) of the hPTH analog, [Leu(27)]-cyclo(Glu(22)-Lys(26))-hPTH-(1--31)NH(2), for 6 weeks does not prevent the ovariectomy-induced loss of rat femoral cancellous bone volume, trabecular thickness or trabecular number. CONCLUSION These results support the absolute requirement of daily injections for the osteogenic action of hPTH on bone.
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Stimulation of membrane-associated protein kinase-C activity in spleen lymphocytes by hPTH-(1-31)NH2, its lactam derivative, [Leu27]-cyclo(Glu22-Lys26)-hPTH-(1-31)NH2, and hPTH-(1-30)NH2. Cell Signal 1999; 11:159-64. [PMID: 10353689 DOI: 10.1016/s0898-6568(98)00055-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Human parathyroid hormone, hPTH-(1-34), stimulates adenylyl cyclase and phosphatidylinositol-bisphosphate-specific phospholipase-C (PIP2-PLC), as indicated by increased membrane-associated protein kinase C (PKC) activity in ROS 17/2 rat osteosarcoma cells. The C-terminally truncated hPTH-(1-31)NH2 stimulates adenylyl cyclase as strongly as hPTH-(1-34) in these cells, but it does not stimulate PKC activity. Even [Leu27]-cyclo(Glu22-Lys26)-hPTH-(1-31)NH2, a 6-fold stronger adenylyl cyclase stimulator than hPTH-(1-34), cannot stimulate PKC activity in ROS cells. Therefore PTH required its 32-34 region to stimulate PIP2-PLC/PKCs in this osteosarcoma line. In contrast, hPTH-(1-31)NH2 [Leu27]-cyclo(Glu22-Lys26)-hPTH-(1-31)NH2 and even hPTH-(1-30)NH2 can stimulate PKC activity in freshly isolated rat spleen lymphocytes as strongly as hPTH-(1-34)NH2. The difference in the ability of membrane-associated PKC activity in spleen lymphocytes, but not in ROS cells, to be stimulated by C-terminally truncated PTH fragments might be due to different receptor densities or to the lymphocyte's atypical PTH/PTHrP receptor.
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Serum markers of treatment success in leprosy. INTERNATIONAL JOURNAL OF LEPROSY AND OTHER MYCOBACTERIAL DISEASES : OFFICIAL ORGAN OF THE INTERNATIONAL LEPROSY ASSOCIATION 1999; 67:19-23. [PMID: 10407625] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
UNLABELLED Intercellular adhesion molecule-1 (ICAM-1) and E-selectin and other variables were evaluated as possible markers of the success of multidrug therapy (MDT) in leprosy. Multibacillary (MB, N = 45) and paucibacillary (PB, N = 29) leprosy patients were examined during MDT, which typically lasted 12 months for MB and 6 months for PB patients. Serum values for total protein, albumin, immunoglobulin gamma (IgG), ICAM-1, and E-selectin (selectin) were recorded, as were lesion type, number, and distribution. Response at the end of therapy was assessed as good, fair, or poor. The bacterial index (BI) of lesions was measured at the beginning and end of therapy. The earlier reported findings of this investigation are herein re-examined. RESULTS age and lowered serum albumin correlated with the poorer condition of the patients, as did elevated selectin. Albumin was inversely correlated with the BI (p = 0.008) in MB patients, and IgG was positively correlated (p = 0.009). ICAM and E-selectin alone were not useful markers of individual patient condition. A regression combining serum albumin under 41 g/l, age and E-selectin was able to identify 85% of the patients in poorer condition. CONCLUSION serum albumin was a useful nonspecific marker of both patient condition and infection. Age is an important negative factor in patient response. Albumin and IgG correlate with the BI and with each other (p = 0.011) in MB patients, but not in PB patients.
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Comparison of the abilities of human parathyroid hormone (hPTH)-(1-34) and [Leu27]-cyclo(Glu22-Lys26)-hPTH-(1-31)NH2 to stimulate femoral trabecular bone growth in ovariectomized rats. Calcif Tissue Int 1998; 63:423-8. [PMID: 9799828 DOI: 10.1007/s002239900551] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
hPTH-(1-31)NH2, so far the smallest of the potently anabolic N-terminal fragments of the human parathyroid hormone, stimulates trabecular growth in the distal femurs of ovariectomized (OVX) rats as strongly as hPTH-(1-34) when injected at a high daily dose such as 1 nmol/100 g of body weight, but it is only about 70% as effective as hPTH-(1-34) when injected at the suboptimal 0.6 nmol/100 g of body weight. A lactam derivative of hPTH-(1-31)-NH2, [Leu27]-cyclo(Glu22-Lys26)-hPTH-(1-31)NH2, is a much more effective stimulator of adenylyl cyclase in ROS 17/2 rat osteoblast-like cells and a significantly more effective stimulator of femoral trabecular growth in OVX rats than hPTH-(1-31)NH2. We have now shown that [Leu27]-cyclo(Glu22-Lys26)-hPTH-(1-31)NH2 prevents the OVX-induced loss of femoral trabeculae significantly more effectively than hPTH-(1-34) and stimulates the thickening of the trabeculae remaining in severely depleted femoral trabecular bone of OVX rats as effectively as hPTH-(1-34) when injected at 0.6 nmol/100 g of body weight.
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Data elements for emergency department systems, release 1.0 (DEEDS): a summary report. DEEDS Writing Committee. Ann Emerg Med 1998; 31:264-73. [PMID: 9472191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Variations in the way that data are entered in emergency department record systems impede the use of ED records for direct patient care and deter their reuse for many other legitimate purposes. To foster more uniform ED data, the Centers for Disease Control and Prevention's National Center for Injury Prevention and Control is coordinating a public-private partnership that has developed recommended specifications for many observations, actions, instructions, conclusions, and identifiers that are entered in ED records. The partnership's initial product, Data Elements for Emergency Department Systems, Release 1.0 (DEEDS), is intended for use by individuals and organizations responsible for ED record systems. If the recommended specifications are widely adopted, then problems--such as data incompatibility and high costs of collecting, linking, and using data--can be substantially reduced. The collaborative effort that led to DEEDS, Release 1.0 sets a precedent for future review and revision of the initial recommendations.
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Susan MacLean, RN, PhD, director, ENA research services. J Emerg Nurs 1998; 24:90-4. [PMID: 9534544 DOI: 10.1016/s0099-1767(98)90187-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Data elements for emergency department systems, release 1.0 (DEEDS): a summary report. DEEDS Writing Committee. J Emerg Nurs 1998; 24:35-44. [PMID: 9534532 DOI: 10.1016/s0099-1767(98)90168-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Variations in the way that data are entered in ED record systems impede the use of ED records for direct patient care and deter their reuse for many other legitimate purposes. To foster more uniform ED data, the Centers for Disease Control and Prevention's (CDC) National Center for Injury Prevention and Control is coordinating a public-private partnership that has developed recommended specifications for many observations, actions, instructions, conclusions, and identifiers that are entered in ED records. The partnership's initial product. Data Elements for Emergency Department Systems, Release 1.0 (DEEDS), is intended for use by individuals and organizations responsible for ED record systems. If the recommended specifications are widely adopted, then problems--such as data incompatibility and high costs of collecting, linking, and using data--can be substantially reduced. The collaborative effort that led to DEEDS, Release 1.0 sets a precedent for future review and revision of the initial recommendations.
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Comparison of the abilities of human parathyroid hormone(1-31)NH2 and human parathyroid hormone-related protein(1-31)NH2 to stimulate femoral trabecular bone growth in ovariectomized rats. Calcif Tissue Int 1997; 61:322-6. [PMID: 9312203 DOI: 10.1007/s002239900342] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
N-terminal fragments of PTH and PTHrP, such as hPTH-(1-34) and hPTHrP-(1-34), are sufficiently similar with respect to amino acid sequence, location of functional domains, and higher order configuration to activate the same PTH/PTHrP receptor and the same two signal enzymes, adenylyl cyclase and phospholipase-Cbeta. Therefore, it was expected that hPTHrP-(1-31)NH2 would stimulate bone growth in ovariectomized rats as strongly as hPTH-(1-31)NH2. Like hPTH-(1-31)NH2, hPTHrP-(1-31)NH2 stimulated adenyly cyclase in ROS 17/2 osteosarcoma cells as strongly as the standard hPTH-(1-34) and like hPTH-(1-31)NH2, triggered a large drop in mean blood pressure when injected intravenously. Unlike hPTH-(1-31)NH2, however, hPTHrP-(1-31)NH2 could not stimulate trabecular growth in the distal femurs of young, sexually mature, ovariectomized rats.
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When the biological indicator is positive: investigating autoclave failures. Infect Control Hosp Epidemiol 1997; 18:654-6. [PMID: 9309439 DOI: 10.1086/647692] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
A series of positive biological indicators in steam autoclaves from different hospital departments within the same building were traced to blocked steam traps on building condensate lines. The steps taken during the investigation and a protocol for management of positive biological indicators are described.
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When the Biological Indicator Is Positive: Investigating Autoclave Failures. Infect Control Hosp Epidemiol 1997. [DOI: 10.2307/30141494] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Cyclization by a specific lactam increases the ability of human parathyroid hormone (hPTH)-(1-31)NH2 to stimulate bone growth in ovariectomized rats. J Bone Miner Res 1997; 12:1246-52. [PMID: 9258755 DOI: 10.1359/jbmr.1997.12.8.1246] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Human parathyroid hormone (hPTH)-(1-31)NH2 (Ostabolin), which only stimulates adenylyl cyclase (AC) instead of AC and phospholipase-C as do hPTH(1-84) and hPTH(1-34), strongly stimulates femoral cortical and trabecular bone growth in ovariectomized (OVX) rats. Two side-chain lactams have been introduced in the hydrophilic face of the receptor-binding region of the fragment's Ser17-Val31 amphiphilic alpha-helix in an attempt to develop improved analogs for the treatment of osteoporosis. Replacing the polar Lys27 with an apolar Leu on the hydrophobic face of this alpha-helix and stabilizing the helix with a lactam between Glu22 and Lys26 produced a fragment, [Leu27]-cyclo(Glu22-Lys26)-hPTH(1-31)NH2, which had six times the AC-stimulating ability of hPTH(1-31)NH2 in ROS 17/2 rat osteosarcoma cells, but the other helix-stabilizing lactam derivative [Leu27]-cyclo(Lys26-Arg30)-hPTH(1-31)NH2 did not have a greater AC-stimulating ability than hPTH(1-31)NH2, to stimulate AC in ROS 17/2 rat osteosarcoma cells. As expected from AC stimulation being responsible for PTH's anabolic action, [Leu27]-cyclo(Glu22-Lys26)-hPTH(1-31)NH2 was, depending on the experimental design, a 1.4 to 2 times better stimulator of trabecular bone growth in the OVX rat model than either hPTH(1-31)NH2 or [Leu27]-cyclo(Lys26-Arg30)-hPTH(1-31)NH2. Thus, there is now a more potently anabolic derivative of hPTH(1-31)NH2, [Leu27]-cyclo(Glu22-Lys26)-hPTH(1-31)NH2, which might ultimately prove to be one of the more effective therapeutics for osteoporosis.
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Comparison of the ability of recombinant human parathyroid hormone, rhPTH-(1-84), and hPTH-(1-31)NH2 to stimulate femoral trabecular bone growth in ovariectomized rats. Calcif Tissue Int 1997; 60:26-9. [PMID: 9030476 DOI: 10.1007/s002239900181] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
A recombinant human parathyroid hormone, rhPTH-(1-84), which is currently in Phase II clinical trial, and hPTH-(1-31)NH2 (Ostabolin) are promising anabolic agents for treating osteoporosis because they can stimulate cortical and trabecular bone growth in osteopenic, ovariectomized (OVX) rats and in osteoporotic, postmenopausal women when injected subcutaneously and intermittently at low doses. We have now found that, despite their different sizes and signaling properties (rhPTH-(1-84) stimulates adenylyl cyclase and phospholipase C; hPTH-(1-31)NH2 only stimulates adenylyl cyclase), they are equally osteogenic in OVX rats. Thus daily subcutaneous injections of 0.6 nmol/100 g of body weight of rhPTH-(1-84) or hPTH-(1-31)NH2 into 3-month-old OVX rats for 6 weeks starting 2 weeks after OVX equally reduced the otherwise large OVX-triggered loss of femoral trabecular bone. Daily subcutaneous injections of 0. 4 or 0.8 nmol/100 g of body weight of the two agents for 6 weeks also equally increased the mean thickness of the remaining femoral trabeculae in 3-month-old and 1-year-old OVX rats to 20 to 80% above the value in normal animals when started 9 weeks after ovariectomy.
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Abstract
BACKGROUND The cerebrospinal fluid (CSF)-Venereal Disease Research Laboratory (VDRL) test is only 27% sensitive for diagnosing neurosyphilis. Discriminant analysis, used on 124 patients, shows that other commonly used laboratory tests can, in combination, identify 87% of patients with neurosyphilis with 94% specificity. STUDY DESIGN The insensitivity of the CSF-VDRL (27% in persons with neurosyphilis) and the foreseen greater need to identify and treat neurosyphilis in the era of human immunodeficiency virus caused us to analyze the serum and cerebrospinal fluid results of 73 patients with syphilis and of 51 patients with clinically diagnosed neurosyphilis. Discriminant analysis was applied to different sets of laboratory tests to find the combination of test results best able to predict retrospectively the clinical diagnosis of syphilis or neurosyphilis, without reference to the CSF-VDRL. RESULTS The predicting function averages 94% specificity and 87% sensitivity. Test result variables considered together are: CSF-FTA-ABS, serum FTA-ABS, CSF-TPHA, serum TPHA, and CSF cells. CONCLUSIONS The authors conclude that clinicians or laboratories can, independently of the CSF-VDRL, compute a score showing whether the results of a set of commonly used tests suggest neurosyphilis in a patient.
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IM injection volume limit. Am J Nurs 1996; 96:13. [PMID: 8659559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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Motor vehicle injury prevention grant projects under way. J Emerg Nurs 1996; 22:38A. [PMID: 8716317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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C-terminal fragment of parathyroid hormone-related protein, PTHrP-(107-111), stimulates membrane-associated protein kinase C activity and modulates the proliferation of human and murine skin keratinocytes. J Cell Physiol 1996; 166:1-11. [PMID: 8557757 DOI: 10.1002/(sici)1097-4652(199601)166:1<1::aid-jcp1>3.0.co;2-t] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Low concentrations of the C-terminal parathyroid hormone-related protein (PTHrP) fragments, PTHrP-(107-111) and PTHrP-(107-139), stimulated membrane-associated protein kinase Cs (PKCs), but not adenylyl cyclase or an internal Ca2+ surge, in early passage human skin keratinocytes and BALB/MK-2 murine skin keratinocytes. The fragment maximally stimulated membrane-associated PKCs in BALB/MK-2 cells at 5 x 10(-9) to 10(-8) M. The maximally PKC-stimulating concentrations of PTHrP-(107-111) also stopped or stimulated BALB/MK-2 keratinocyte proliferation depending on whether the cells were, respectively, cycling or quiescent at the time of exposure. Thus, just one brief (30-minute) pulse of 10(-8) M PTHrP-(107-111) stopped the proliferation of BALB/MK-2 keratinocytes for at least 5 days. On the other hand, daily 30-minute pulses of 10(-8) M PTHrP-(107-111) started and then maintained the proliferation of initially quiescent BALB/MK-2 cells. Similarly PTHrP-(107-111) inhibited DNA synthesis by cycling primary adult human keratinocytes, but it stimulated DNA synthesis by quiescent human keratinocytes.
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The use of bioelectrical impedance analysis (BIA) to estimate body composition in the Diabetes Control and Complications Trial (DCCT). INTERNATIONAL JOURNAL OF OBESITY AND RELATED METABOLIC DISORDERS : JOURNAL OF THE INTERNATIONAL ASSOCIATION FOR THE STUDY OF OBESITY 1994; 18:829-835. [PMID: 7894522] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Although weight gain often accompanies intensive treatment regimens designed to achieve near-normal glycemia in insulin-dependent diabetes mellitus (IDDM), body composition (BC) has not been well studied. Bioelectrical impedance analysis (BIA) is a safe, rapid, and non-invasive method of assessing BC but has not been utilized widely in IDDM. Data from 46 adults with IDDM were used to develop a regression model estimating fat-free body mass (FFM) from bioimpedance measurements obtained using a proximal electrode placement. Reference values of FFM were determined by dual x-ray absorptiometry (DXA). A model using the ratio of height squared to the minimum resistance of 4 limb-lead combinations (H2/R), total body weight, and a weight-gender interaction achieved a high level of accuracy (R2 = 0.982, residual standard deviation = 1.43 kg), while studies of 10 subjects before and after a light meal found no short-term effect of glycemia on measured BIA variables. BIA will therefore be used in combination with waist-to-hip ratios to study the composition and distribution of the increased weight associated with intensive therapy in the DCCT.
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New ENA director of research enthusiastic about emergency nursing research potential. J Emerg Nurs 1994; 20:30A-31A. [PMID: 7745882] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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Abstract
N-terminal fragments of PTH-related protein (PTHrP), PTHrP-(1-34), and PTHrP-(1-40) stimulated both adenylyl cyclase and a mechanism that increases membrane-associated protein kinase C (PKC) activity in ROS 17/2 rat osteosarcoma cells. There were two peaks in the PKC response to the N-terminal PTHrP fragments: one peak was obtained with picomolar and the other with nanomolar PTHrP concentrations. The PKC-stimulating picomolar concentrations of the PTHrP fragments did not detectably stimulate adenylyl cyclase, but the nanomolar concentrations did. Since a similar two-peak response of PKC activity was obtained with PTHrP-(28-34), the single, N-terminal PKC activation domain of the PTHrP is in the same 28-34 region of the molecule as that of PTH despite this region having different primary amino acid sequences in the two hormones. Unlike PTH, PTHrP has a second PKC activation domain, as indicated by the ability of picomolar concentrations of the PTHrP-(107-111) fragment to stimulate maximally membrane-associated PKC activity in the osteosarcoma cells.
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Abstract
Forty captive wapiti (Cervus elaphus) and thirty-two bison (Bison bison bison) were tested in April and October 1988, respectively, for their response to the sedative R51163. Treatment animals were injected with either 0.1, 0.2, or 0.3 mg of R51163/kg and then observed for 72 hr. Behavior was significantly altered by the drug. Hyperactive, aggressive, and milling behavior was characteristic of treated wapiti and they were extremely dangerous and reared when hind quarters were touched. Although treated plains bison displayed some milling behavior, they were generally more calm than wapiti. There was a marked difference between sexes in plains bison for all behavioral categories. Male bison were more ataxic, often observed in sternal or lateral recumbency, less conscious, and were slower to respond than females or controls. Respiratory rate increased in treated wapiti and plains bison, and heart rates of treated wapiti increased. Because of the powerful sedative effect on large, male bison, R51163 may be useful for handling unmanageable or dangerous animals and warrants further studies.
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Abstract
The PTH activates both adenylate cyclase and a mechanism that increases membrane-associated protein kinase-C (PKC) activity. To define the hormone's PKC activation domain we have used a panel of PTH fragments and ROS 17/2 rat osteosarcoma cells as the target cells. PTH equally and maximally increased PKC activity in ROS 17/2 cell membranes at physiological concentrations between 1-50 pM and 5-50 nM, but not at intermediate concentrations or concentrations above 50 nM. The PKC-stimulating picomolar concentrations of PTH did not stimulate adenylate cyclase in ROS 17/2 cells, while the PKC-stimulating nanomolar concentrations of the hormone did stimulate adenylate cyclase, with an EC50 of 1-2 nM. Very high concentrations of PTH, such as 100 nM, that did not increase membrane PKC activity were still able to maximally stimulate adenylate cyclase. PTH fragments lacking the N-terminal amino acids needed for adenylate cyclase activation increased membrane PKC activity, and the PKC activation domain was found to lie within the 28-34 region of the PTH molecule. This was confirmed by showing that optimally effective picomolar concentrations of the human PTH-(28-34) fragment itself were able to increase membrane-associated PKC activity to the same extent as the optimally effective picomolar concentrations of the intact PTH-(1-84) or the larger PTH-(1-34) or PTH-(3-34) fragments.
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Purification and characterization of purine nucleoside phosphorylase from Proteus vulgaris. Appl Environ Microbiol 1990; 56:1435-9. [PMID: 2111121 PMCID: PMC184424 DOI: 10.1128/aem.56.5.1435-1439.1990] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Purine nucleoside phosphorylase was isolated and purified from cell extracts of Proteus vulgaris recovered from spoiling cod fish (Gadus morhua). The molecular weight and isoelectric point of the enzyme were 120,000 +/- 2,000 and pH 6.8. The Michaelis constant for inosine as substrate was 3.9 x 10(-5). Guanosine also served as a substrate (Km = 2.9 x 10(-5). However, the enzyme was incapable of phosphorylizing adenosine. Adenosine proved to be useful as a competitive inhibitor and was used as a ligand for affinity chromatography of purine nucleoside phosphorylase following initial purification steps of gel filtration and ion-exchange chromatography.
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The Gerson therapy. Interview by Pamela Holmes. NURSING TIMES 1988; 84:41-2. [PMID: 2834697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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