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Boyce W, Fisher A, Provencio H, Rominger E, Thilsted J, Ahlm M. Elaeophorosis in bighorn sheep in New Mexico. J Wildl Dis 1999; 35:786-9. [PMID: 10574542 DOI: 10.7589/0090-3558-35.4.786] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Two bighorn sheep (Ovis canadensis) in New Mexico (USA) were found to be naturally infected with Elaeophora schneideri. An adult ram examined in 1997 in the Fra Cristobal Mountains had 26 nematodes in the carotid and iliac arteries, and microfilariae were present in the skin, nasal mucosa, brain, and lungs. This ram was markedly debilitated prior to euthanasia and extensive crusty, scabby lesions were observed on its head. In 1998, a yearling ewe found dead adjacent to Watson Mountain near the Gila Wilderness area was found to have 13 nematodes present in its heart. This is the first report of E. schneideri in bighorn sheep, and we suggest that bighorn sheep are susceptible to E. schneideri infection wherever they coexist with mule deer (Odocoileus hemionus hemionus) and appropriate tabanid vectors.
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Pavone P, Greco F, Fisher A, Zancan L, D'Agata A, Musumeci S. Bone marrow hypoplasia associated with acute viral hepatitis in four children. Minerva Pediatr 1999; 51:319-24. [PMID: 10783593] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Four cases of children, aged 2 to 11 years, with acute viral hepatitis and bone marrow hypoplasia are reported. Three patients presented only jaundice and hepatomegaly; one also had liver failure. All the four patients underwent bone marrow aspiration which showed bone marrow aplasia. In two of the four patients a liver biopsy revealed patchy necrosis with inflammatory mononuclear cell infiltrate. Half of the patients received a bone marrow transplantation; the remaining patients were treated by intravenous infusion of immunoglobulins, growth factors and steroids. The main epidemiological and etiological features of such association are also reported.
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Melbourne KM, Geletko SM, Brown SL, Willey-Lessne C, Chase S, Fisher A. Medication adherence in patients with HIV infection: a comparison of two measurement methods. THE AIDS READER 1999; 9:329-38. [PMID: 12737122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/02/2023]
Abstract
Two measurements of adherence, patient self-report and electronic measurement by the Medication Event Monitoring System (MEMS), were compared in a 3-month adherence study of 44 HIV-infected patients who had been placed on regimens that included protease inhibitors (PIs). The dose percentage and degree of clinically significant dosing time fluctuation were calculated monthly. The mean dose percentage by self-report versus MEMS was 97.5% versus 90.3% during month 1 of adherence monitoring, 96.5 versus 90.1% during month 2, and 98.4% versus 92.8% during month 3. Thirty-two percent of patients taking PIs and 21% of patients taking nucleoside analogues demonstrated clinically significant dosing time fluctuation. Our data confirm that self-reports of adherence overestimate true adherence behavior, and patients' self-reports of dosing times may not accurately reflect their deviation from those times.
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Liaschenko J, Fisher A. Theorizing the knowledge that nurses use in the conduct of their work. SCHOLARLY INQUIRY FOR NURSING PRACTICE 1999; 13:29-41. [PMID: 10420795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
The authors propose a classification of knowledge that they call case, patient, and person and that reflects the content of the knowledge necessary to the conduct of nursing work. This classification represents an attempt to theorize from their respective empirical research data. Case knowledge is general knowledge of pathophysiology, disease processes, pharmacology, and other therapeutic protocols. Patient knowledge is that knowledge that defines the individual within the health care system, the knowledge expressed in the individual's response to therapeutics, and the knowledge that enables nurses to move the recipient of care through the health care system and along the illness trajectory. Person knowledge is knowledge of the individual as a subject with a personal biography who occupies a certain social space and who acts with his or her own desires and intentions for reasons that make sense to him or her. Two types of social knowledge serve as relational knowledge, or a bridge that links case knowledge to patient knowledge and patient knowledge to person knowledge. Each type of knowledge is accessed differently and the extent to which each is attained and used is determined by the circumstances of the patient's illness and his or her location in the health care system. The authors make a case for why this classification might be useful to the discipline.
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Abstract
The use of a cuffed tracheal tube is described to occlude the leak through a tracheo-oesophageal fistula (TOF) in a neonate and prevent gastric dilatation during positive-pressure lung ventilation.
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Fisher A, McLean AJ, Purcell P, Herdson PB, Dahlstrom JE, Le Couteur DG. Focal necrotising vasculitis with secondary myositis following fluoxetine administration. AUSTRALIAN AND NEW ZEALAND JOURNAL OF MEDICINE 1999; 29:375-6. [PMID: 10868505 DOI: 10.1111/j.1445-5994.1999.tb00726.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Montagna D, Yvon E, Calcaterra V, Comoli P, Locatelli F, Maccario R, Fisher A, Cavazzana-Calvo M. Depletion of alloreactive T cells by a specific anti-interleukin-2 receptor p55 chain immunotoxin does not impair in vitro antileukemia and antiviral activity. Blood 1999; 93:3550-7. [PMID: 10233908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023] Open
Abstract
The success of bone marrow transplantation (BMT) from HLA-disparate donors depends on the development of new strategies able, on one hand, to efficiently prevent graft-versus-host disease (GVHD) and, on the other hand, to protect leukemic patients from relapse and infections. Using an immunotoxin (IT) directed against the alpha chain (p55) of the human interleukin-2 receptor (RFT5-SMPT-dgA), we previously showed that it is possible to kill mature T cells activated against a specific HLA complex by a one-way mixed lymphocyte culture (MLC). The present study was performed to investigate whether this protocol of allodepletion affects the capacity of residual T cells to display antileukemia and antiviral activity evaluated by limiting dilution assays (LDA), measuring the frequency of cytotoxic T-lymphocyte precursors (CTLp) directed against autologous leukemic blasts (LB) and cytomegalovirus (CMV)- and Epstein-Barr virus (EBV)-infected target cells. Antileukemia activity was evaluated in peripheral blood mononuclear cells (PBMC) of 3 patients treated for acute myeloid leukemia who had developed a high frequency of LB-reactive CTLp after either autologous or allogeneic BMT. Results demonstrate that (1) depletion with RFT5-SMPT-dgA efficiently inhibited MLC; (2) fresh PBMC of patients yielded a high frequency of LB-reactive CTLp comparable to that of the mock-treated PBMC; and (3) effector cells obtained after allodepletion fully retained the capacity to lyse pretransplant LB. By contrast, the frequency of CTLp directed against patient's pretransplant BM remission cells was always undetectable. Data obtained in 4 healthy donors showed that specifically allodepleted T cells recognized and killed autologous CMV-infected fibroblasts and autologous EBV-B-lymphoblastoid cell lines. In conclusion, our data indicate that allodepletion using RFT5-SMPT-dgA efficiently removed alloreactive cells, while sparing in vitro antileukemic and antiviral cytotoxic responses.
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Clark K, Fisher A, Keown J, Neville W. Early induction of labor: legal and ethical considerations. LINACRE QUARTERLY 1999; 66:7-25. [PMID: 12199287 DOI: 10.1080/20508549.1999.11877536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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234
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O'Neill J, Fitten LJ, Siembieda DW, Crawford KC, Halgren E, Fisher A, Refai D. Divided attention-enhancing effects of AF102B and THA in aging monkeys. Psychopharmacology (Berl) 1999; 143:123-30. [PMID: 10326774 DOI: 10.1007/s002130050927] [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: 10/28/2022]
Abstract
The effects of cholinergic drugs proposed for treatment of cognitive impairment in normal aging and dementia on divided attention have been little studied in non-human primates. We tested the hypothesis that cholinergic drugs improve spatial divided attention in primates via a computer task requiring simultaneous tracking of two visual targets in three young and two aged healthy bonnet macaques. Task accuracy (number of correct responses) and reaction time (RT) were measured 2 h after administration of either the m1 agonist +/- -cis-2-methyl-spiro(1,3-oxathiolane-5,3')quinuclidine (AF102B; 0.1-2.1 mg/kg IM) or the cholinesterase inhibitor 9-amino-1,2,3,4-tetrahydroamino-acridine (THA; 0.5-2.0 mg/kg orally). Accuracy increased for four of five monkeys at appropriate doses of one or both cholinomimetics, accompanied in two monkeys by a drop in RT. Responses were less uniform to THA than to AF102B. For the five-monkey group at Best dose, accuracy increased 34% (THA) or 43% (AF102B) above baseline (P<0.05 for both drugs), respectively, with no significant change in RT and with minimal untoward effects. Cholinotherapy may improve divided attention in young and aged healthy primates.
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Fitten LJ, Ortiz F, Siembieda DW, O'Neill J, Halgren E, Fisher A. Reduction of motoric agitation and restlessness by AF102B and tacrine in the macaque. J Neuropsychiatry Clin Neurosci 1999; 11:79-85. [PMID: 9990560 DOI: 10.1176/jnp.11.1.79] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The cholinesterase inhibitor tacrine (THA) and the M1 muscarinic agonist AF102B (cevimeline), both reported to enhance cognition in animals and humans, were tested in 5 macaques for reduction of spontaneous, random movements. Monkeys were videotaped 1 hour after administration of normal saline vehicle, after low- and high-dose intramuscular AF102B, and after low- and high-dose oral THA. Two independent blind judges counted numbers of spontaneous movements made by each monkey over 12 consecutive 15-second segments for each drug condition. Both THA and AF102B reduced movement significantly at high doses without overt side effects, warranting further research on the agitation-reducing potential of cognition-enhancing cholinomimetic drugs.
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Goldberg MR, Lowry RC, Musson DG, Birk KL, Fisher A, De Puy ME, Shadle CR. Lack of pharmacokinetic and pharmacodynamic interaction between rizatriptan and paroxetine. J Clin Pharmacol 1999; 39:192-9. [PMID: 11563413 DOI: 10.1177/00912709922007633] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Rizatriptan is a potent, oral 5-HT(1B/1D) agonist with a rapid onset of action being investigated for the acute treatment of migraine. This study examined the clinical and pharmacolinetic interaction between rizatriptan and the selective serotonin reuptake inhibitor, paroxetine. In this two-period crossover study, 12 healthy young subjects (6 males and 6 females) received 1 mg rizatriptan following 14 days of treatment with placebo or paroxetine (20 mg once daily). Plasma was sampled for rizatriptan and N-monodesmethyl rizatriptan, a minor but active metabolite of rizatriptan. Safety evaluations included monitoring for adverse events, vital signs, and visual analog scale assessment of mood. Plasma levels of rizatriptan and N-monodesmethyl rizatriptan were not altered when rizatriptan was administered with paroxetine compared to the placebo. Clinically, coadministration of rizatriptan with paroxetine was well tolerated. Blood pressure, heart rate, and temperature changes during the observation period did not differ to a clinically significant degree when rizatriptan was administered with paroxetine compared to the placebo. No effects on mood occurred following treatment with the combination compared to rizatriptan alone. Adverse events following rizatriptan administration with paroxetine were similar to those reported when rizatriptan was given with the placebo.
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Grey MR, Burgess R, Fisher A, Yin JA. Effect on cell kill of addition of multidrug resistance modifiers cyclosporin A and PSC 833 to cytotoxic agents in chronic lymphocytic leukaemia. Leuk Res 1999; 23:29-35. [PMID: 9933132 DOI: 10.1016/s0145-2126(98)00136-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Expression of P-glycoprotein (Pgp), the drug efflux pump which mediates multidrug resistance (MDR), has been widely reported in chronic lymphocytic leukaemia (CLL) and improved accumulation of daunorubicin has been reported using the MDR reversing agent cyclosporin A (CSA). We have investigated the effects on cell kill of the addition of CSA and its analogue PSC 833 to daunorubicin, doxorubicin, idarubicin, mitozantrone and fludarabine in samples from 51 patients with CLL using an MTT [3(4,5-dimethylthaizol-2-yl)-2,5-diphenyltetrazolium bromide] assay. Pgp expression was assessed by immunocytochemistry using the JSB-1 monoclonal antibody. Of the 51 samples, 10 (20%) were Pgp positive and all of these samples were from treated patients. With the exception of mitozantrone, the addition of CSA and PSC 833 to cytotoxic agents failed to significantly improve cytotoxicity, even in the Pgp positive group. With mitozantrone significant responses were seen in both Pgp positive and negative groups suggesting that the responses were due to direct cytotoxicity of the cytotoxic-modifier combination rather than reversal of MDR. Both CSA and PSC 833 showed significant direct cytotoxicity (P = 0.004 and 0.04 for PSC 833 at 1000 ng/ml and 500 ng/ml respectively; P < 0.001 for both concentrations of CSA). The responses were disappointing compared to the highly significant improvements in cytotoxicity seen using cells from the Pgp positive CEM VLB 100 acute myeloid leukaemia cell line, and it was not possible to demonstrate the superiority of PSC 833 over CSA which is also seen in cell lines. Our data do not support a role for Pgp modifiers in CLL. Further studies using larger numbers of Pgp positive CLL cells and higher doses of PSC 833 would be useful.
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Pittel Z, Fisher A, Eshhar N, Haring R, Heldman E. Effect of muscarinic stimulation on β-amyloid precursor protein processing in rat brain and primary cultures. Life Sci 1999. [DOI: 10.1016/s0024-3205(99)90500-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Woinarski JCZ, Palmer C, Fisher A, Brennan K, Southgate R, Masters P. Distributional patterning of mammals on the Wessel and English Company Islands, Arnhem Land, Northern Territory, Australia. AUST J ZOOL 1999. [DOI: 10.1071/zo99004] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Eighteen non-marine mammal species (including seven species of bats) were
recorded from a total of 49 islands in the Wessel and English Company island
chains off north-eastern Arnhem Land, Northern Territory. Most individual
species were restricted to, or had higher incidence on, larger islands, and
species richness as a whole increased as island size increased. The most
notable exception was the semi-aquatic
Hydromys chrysogaster, which occurred relatively
equitably across island sizes; this species, two bat species and the macropod
Petrogale brachyotis were recorded from islands smaller
than 10 ha. However, the variation between islands in the number of native
terrestrial mammal species was not best predicted by island size, but rather
by a combination of sampling effort and altitude (which explained 64%
of the deviance in species richness), or altitude and distance to larger land
mass (explaining 63% of deviance).
Richness–area patterns for individual islands in these chains were
reasonably consistent with those of other islands sampled in northern
Australia. However, the fauna of the Wessel and English Company groups as a
whole was less rich than that of the Pellew and Kimberley islands, and
individual islands appeared to have lower species richness than comparable
mainland areas. Species that were notably absent or that were recorded from
relatively few islands include large macropods,
Tachyglossus aculeatus, Antechinus bellus, Phascogale tapoatafa, Sminthopsis spp., Mesembriomys gouldii, Rattus colletti, Leggadina lakedownensis
and Pseudomys calabyi. Some of these species may be
absent through lack of suitable habitat; others have presumably disappeared
since isolation, possibly due to Aboriginal hunting.
Richness at the quadrat (50 × 50 m) scale was generally very low.
Habitat relationships are described for the 7 species recorded from more than
5 quadrats. At a quadrat-scale, the richness of native mammals was greater on
islands larger than 1000 ha than on islands smaller than 1000 ha.
Quadrat-scale species richness varied significantly among the islands sampled
by the most quadrats (even when the comparison was restricted to either of the
two most extensive vegetation types), but this variation was not closely
related to either area or altitude. The two most frequently recorded species,
the rodents Melomys burtoni and
Zyzomys argurus, showed distinct habitat segregation on
islands where both were present, but tended to expand their habitat range on
islands where only one of the species occurred.
The most notable conservation feature of the mammal fauna of the Wessel and
English Company Islands is the occurrence of the golden bandicoot,
Isoodon auratus, a vulnerable species apparently now
extinct on the Northern Territory mainland. Four feral animal species
(Rattus rattus, Canis familiaris, Bubalus bubalis and
Capra hircus) were recorded from a total of 6 islands.
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Fisher A, Biggs CS, Starr MS. Effects of glutamate antagonists on the activity of aromatic L-amino acid decarboxylase. Amino Acids 1999; 14:43-9. [PMID: 9871440 DOI: 10.1007/bf01345241] [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: 11/29/2022]
Abstract
This study examines the hypothesis that glutamate tonically suppresses the activity of the enzyme aromatic L-amino acid decarboxylase (AADC), and hence the biosynthesis of dopamine, to explain how antagonists of glutamate receptors might potentiale the motor actions of L-DOPA in animal models of Parkinson's disease. A variety of glutamate antagonists were therefore administered acutely to normal rats, which were sacrificed 30-60 min later and AADC activity assayed in the substantia nigra pars reticulata (SNr) and corpus striatum (CS). The NMDA receptor-ion channel antagonists MK 801, budipine, amantadine, memantine and dextromethorphan all caused a pronounced in creased in AADC activity, more especially in the SNr than CS. The NMDA glycine site antagonist (R)-HA 966 produced a modest increase in AADC activity in the CS but not SNr, whilst the NMDA polyamine site antagonist eliprodil, the NMDA competitive antagonist CGP 40116 and the AMPA antagonist NBQX were without effect. The results suggest that an increase in dopamine synthesis might contribute to the L-DOPA-facilitating actions of some glutamate antagonists.
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Woinarski JCZ, Gambold N, Fisher A, Wurst D, Flannery TF, Smith AP, Chatto R. Distribution and habitat of the northern hopping-mouse, Notomys aquilo. WILDLIFE RESEARCH 1999. [DOI: 10.1071/wr97059] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Current documentation and specimen data for
Notomys aquilo are restricted to three localities: Cape
York (one record from the nineteenth century), Groote Eylandt, and central
Arnhem Land (one record). A field survey based on signs of
N. aquilo and Aboriginal information indicated that the
species occurs widely on sandy substrates of Arnhem Land. Recent observation
of signs suggests that it may also persist on Cape York Peninsula. The species
is reasonably common on Groote Eylandt, where it was recorded most frequently
in shrublands (dominated by either Acacia spp.,
Hakea arborescens or
Banksia dentata), but occurred also in coastal
grasslands and other strand vegetation. Its abundance there is associated with
the cover of hummock grass and several pea species. The conservation status of
the species appears to be secure.
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Hatton DC, Fisher A. Strategies for managing health problems among homeless women: three case studies. NURSING CASE MANAGEMENT : MANAGING THE PROCESS OF PATIENT CARE 1999; 4:19-24. [PMID: 10232218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
The purpose of this article is to illustrate through case examples how homeless women experience coexisting health problems, and how they may conceal these stigmatizing health problems from others, including health professionals and shelter staff. The article will also address how nurse case managers can interact with these women so that together they can develop strategies about how to manage these complex health problems.
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Genis I, Fisher A, Michaelson DM. Site-specific dephosphorylation of tau of apolipoprotein E-deficient and control mice by M1 muscarinic agonist treatment. J Neurochem 1999; 72:206-13. [PMID: 9886071 DOI: 10.1046/j.1471-4159.1999.0720206.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Apolipoprotein E (apoE)-deficient mice have memory deficits that are associated with synaptic loss of basal forebrain cholinergic projections and with hyperphosphorylation of distinct epitopes of the microtubule-associated protein tau. Furthermore, treatment of apoE-deficient mice with the M1 selective agonist 1-methylpiperidine-4-spiro-(2'-methylthiazoline) [AF150(S)] abolishes their memory deficits and results in recovery of their brain cholinergic markers. In the present study, we used a panel of anti-tau monoclonal antibodies to further map the tau epitopes that are hyperphosphorylated in apoE-deficient mice and examined the effects of prolonged treatment with AF150(S). This revealed that tau of apoE-deficient mice contains a distinct, hyperphosphorylated "hot spot" domain which is localized N-terminally to the microtubule binding domain of tau, and that AF150(S) has an epitope-specific tau dephosphorylating effect whose magnitude is affected by apoE deficiency. Accordingly, epitopes which reside in the hyperphosphorylated "hot spot" are dephosphorylated by AF150(S) in apoE-deficient mice but are almost unaffected in the controls, whereas epitopes which flank this tau domain are dephosphorylated by AF150(S) in both mice groups. In contrast, epitopes located at the N and C terminals of tau are unaffected by AF150(S) in both groups of mice. These findings suggest that apoE deficiency results in hyperphosphorylation of a distinct tau domain whose excess phosphorylation can be reduced by muscarinic treatment.
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Woinarski JCZ, Brock C, Fisher A, Milne D, Oliver B. Response of Birds and Reptiles to Fire Regimes on Pastoral Land in the Victoria River District, Northern Territory. RANGELAND JOURNAL 1999. [DOI: 10.1071/rj9990024] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Birds and reptiles were censused at two sites of contrasting soil texture (clay, loam) on pastoral land in the Victoria River District, Northern Territory. Both sites comprised 16 plots (each of 2.6 ha) subjected to seven different experimental fire regimes (unburnt, burnt in the early dry season at 2, 4 and 6 year intervals, and burnt in the late dry season at 2, 4 and 6 year intervals) beginning five years before sampling (and thus, not all regimes had been operationally distinct between the onset of the experiment and this sampling). The regimes were deconstructed to four fire factors: the imposed regime, the time since last fire, the number of fires since the inception of the experiment, and the number of hot (=late dry season) fires. Of 30 species recorded from at least four plots, 12 were significantly associated with time since last fire. These responses were mostly to the extremes - some species were associated with the most recently burnt areas, and others occurred mainly in the plots which had been unburnt the longest. Longer- term responses to fire regimes were generally less clearcut, possibly because the relatively short duration of the imposed experimental fire treatments had not yet brought about substantial environmental divergence. Key words: fire regime, tropical savannas, birds, reptiles, diversity.
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Rich JD, Dickinson BP, Carney JM, Fisher A, Heimer R. Detection of HIV-1 nucleic acid and HIV-1 antibodies in needles and syringes used for non-intravenous injection. AIDS 1998; 12:2345-50. [PMID: 9863878 DOI: 10.1097/00002030-199817000-00017] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND HIV antibodies and HIV DNA have been detected in needles and syringes that have been used for intravenous injections in HIV-infected persons. During intravenous injection, blood is typically aspirated into the lumen of the syringe. During intramuscular or subcutaneous injection, however, blood is not usually introduced into the syringe. OBJECTIVES To investigate the presence of HIV antibodies, HIV proviral DNA, HIV RNA, and human DNA in needles and syringes that had been used for intramuscular or subcutaneous injection in persons known to have HIV infection. METHODS Discarded disposable needles and syringes used by health-care personnel for medically indicated intramuscular or subcutaneous injections of HIV-infected patients were collected. Residual material was extracted from the syringes. The extracts were analyzed by enzyme immunoassay for the presence of HIV antibodies. PCR was conducted to detect HIV and human DNA, as well as HIV RNA. RESULTS HIV antibodies were detected in 16 (6.2%) out of 260 syringes. Human DNA or HIV-specific DNA were not detected. A second set of 80 syringes was collected to examine the presence of HIV RNA. HIV RNA was detected in three (3.8%) out of 80 syringes. CONCLUSION This analysis demonstrates that the risk of transmitting HIV from syringes that have been used for intramuscular or subcutaneous injection may be low, but is not zero.
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Haring R, Fisher A, Marciano D, Pittel Z, Kloog Y, Zuckerman A, Eshhar N, Heldman E. Mitogen-activated protein kinase-dependent and protein kinase C-dependent pathways link the m1 muscarinic receptor to beta-amyloid precursor protein secretion. J Neurochem 1998; 71:2094-103. [PMID: 9798935 DOI: 10.1046/j.1471-4159.1998.71052094.x] [Citation(s) in RCA: 99] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Full and functionally selective M1 muscarinic agonists (carbachol and AF102B, respectively) activate secretion of the soluble form of amyloid precursor protein (APPs) in PC12 cells expressing the m1 muscarinic receptor (PC12M1 cells). This activation is further augmented by neurotrophins such as nerve growth factor and basic fibroblast growth factor. Muscarinic stimulation activates two transduction pathways that lead to APPs secretion: protein kinase C (PKC)-dependent and mitogen-activated protein kinase (MAPK)-dependent pathways. These pathways operate in parallel and converge with transduction pathways of neurotrophins, resulting in enhancement of APPs secretion when both muscarinic agonist and neurotrophins stimulate PC12M1 cells. These conclusions are supported by the following findings: (a) Only partial blockade of APPs secretion is observed when PKC, p21ras, or MAPK is fully inhibited by their respective specific inhibitors, GF109203X, S-trans, trans-farnesylthiosalicylic acid, and PD98059. (b) K252a, which blocks PKC and phorbol 12-myristate 13-acetate-induced APPs secretion, enhances both muscarinic-stimulated MAPK activation and APPs secretion. (c) Activation of MAPK in PC12M1 cells by muscarinic agonists is Ras-dependent but PKC-independent and is enhanced synergistically by neurotrophins. These results suggest that muscarinic stimulation of APPs secretion is mediated by at least two independent pathways that converge and enhance the signal for APPs secretion at the convergence point.
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247
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Biggs CS, Fisher A, Starr MS. The antiparkinsonian drug budipine stimulates the activity of aromatic L-amino acid decarboxylase and enhances L-DOPA-induced dopamine release in rat substantia nigra. Synapse 1998; 30:309-17. [PMID: 9776134 DOI: 10.1002/(sici)1098-2396(199811)30:3<309::aid-syn8>3.0.co;2-f] [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: 11/07/2022]
Abstract
The present study examined the effects of the antiparkinsonian drug budipine on dopamine synthesis and release from L-DOPA in the substantia nigra of reserpine-treated rats. Budipine (at 100 microM, but not 10 microM) applied by reverse dialysis to the nigra caused a small and significant rise in dopamine recovery in normal rats, but not in rats pretreated with reserpine (4 mg/kg i.p. for 18 hours) and alpha-methyl-p-tyrosine (alpha-MPT; 200 mg/kg i.p. for 1 hour to limit dopamine synthesis to L-DOPA). L-DOPA applied to the nigra by reverse dialysis in reserpine + alpha-MPT-treated rats, increased the recovery of dopamine when applied at 5 or 10 microM, but not at 2 microM. Coadministration of budipine (10 microM) significantly enhanced L-DOPA-induced dopamine (and DOPAC) release with 5 microM L-DOPA, but not with 2 or 10 microM L-DOPA. This potentiation was even more pronounced when the budipine concentration was raised to 100 microM (equivalent to approximately 10 microM extracellularly). Pretreating rats with budipine (5, 12.5, or 20 mg/kg i.p.) for 1 hour significantly raised the activity of the enzyme L-aromatic amino acid decarboxylase in the striata and nigras of intact rats, as well as in rats pretreated with reserpine alone (5 mg/kg i.p.), without altering tissue levels of dopamine or its metabolites. It is suggested that the beneficial effects of budipine, when used as an adjunct to L-DOPA therapy of Parkinson's disease, may be due to an increase in the bioconversion of L-DOPA with a consequent rise in synaptic dopamine. These actions of budipine may be related to its weak NMDA receptor antagonist property.
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Fisher A, Davies E, Fraser R, Connell JM. Structure-function relationships of aldosterone synthase and 11 beta-hydroxylase enzymes: implications for human hypertension. CLINICAL AND EXPERIMENTAL PHARMACOLOGY & PHYSIOLOGY. SUPPLEMENT 1998; 25:S42-6. [PMID: 9809191 DOI: 10.1111/j.1440-1681.1998.tb02299.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
1. The genes encoding aldosterone synthase (CYP11B2) and 11 beta-hydroxylase (CYP11B1) are very similar at the nucleotide level (> 95% homology). Despite this and the corresponding similarity of amino acid sequence, there are considerable differences in functional and substrate specificity of the two enzymes. In the present study we have examined the role of two amino acids that differ between the two enzymes (147 and 248) to determine the difference between aldosterone synthase and 11 beta-hydroxylase capacity to 11-hydroxylate 11-deoxycorticosterone (DOC). 2. Plasmids containing cDNA encoding wild-type aldosterone synthase, wild-type 11 beta-hydroxylase and mutated forms of aldosterone synthase (D147E and I248T), in which the codons for residues 147 (aspartate exon 3) or 248 (isoleucine exon 4) had been altered to encode the corresponding amino acids (glutamate and threonine respectively) from 11 beta-hydroxylase were transiently expressed in non-steroidogenic COS-7 cells. All transfections were cotransfected with bovine adrenodoxin. Cells were then incubated with [3H]-DOC for 48 h and the production of corticosterone (B), 18-hydroxycorticosterone (18-OHB) and aldosterone measured by measuring tritriated products using thin layer chromatography. 3. Compared with wild-type aldosterone synthase, the mutated form (D147E) encoding amino acid 147 from 11 beta-hydroxylase was more efficient in 11 beta-hydroxylation of deoxycorticosterone (B:DOC ratio 0.53 +/- 0.05 (wild type) to 3.05 +/- 0.37 (mutant); P < 0.001). However, 18-hydroxylation of B and conversion of this steroid into aldosterone were unaffected. There was a 20% increase in the production of aldosterone from DOC (P < 0.05). However, in comparison with wild-type 11 beta-hydroxylase, the mutated aldosterone synthase (D147E) was still less efficient (B:DOC ratio 6.2 +/- 0.41). The mutated aldosterone synthase (I248T) encoding amino acid 248 from 11 beta-hydroxylase showed no changes in conversion of DOC to B or in the production of aldosterone. 4. These data demonstrate that position 147 has an important effect on the efficiency of 11 beta-hydroxylation of DOC and indicate that this is a key difference between the two enzymes in determining functional specificity. However, other residues must also contribute to efficiency of 11-hydroxylation of 11 beta-hydroxylase. In contrast, amino acid 248, which is one of the few differences between the two enzymes in exon 4, does not affect enzyme efficiency. As altered activity of aldosterone synthase and 11 beta-hydroxylase has been proposed as an important intermediate phenotype in essential hypertension, such studies will help our understanding of the structure-function relationships that will be necessary in order to understand how genetic changes may contribute to observed differences in phenotype.
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Fisher A, Brandeis R, Haring R, Eshhar N, Heldman E, Karton Y, Eisenberg O, Meshulam H, Marciano D, Bar-Ner N, Pittel Z. Novel m1 muscarinic agonists in treatment and delaying the progression of Alzheimer's disease: an unifying hypothesis. JOURNAL OF PHYSIOLOGY, PARIS 1998; 92:337-40. [PMID: 9789833 DOI: 10.1016/s0928-4257(99)80001-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
M1 selective agonists from the AF series (e.g. AF102B, AF150(S)), via m1 muscarinic receptors, activate distinct signal transductions, enhance amyloid precursors proteins secretion from transfected cells and primary cell cultures, show neurotrophic effects and are beneficial in a variety of animal models for Alzheimer's disease. Such m1 agonists may be effective in the treatment and therapy of Alzheimer's disease.
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O'Connor RE, Bord RJ, Fisher A. Rating threat mitigators: faith in experts, governments, and individuals themselves to create a safer world. RISK ANALYSIS : AN OFFICIAL PUBLICATION OF THE SOCIETY FOR RISK ANALYSIS 1998; 18:547-556. [PMID: 9853391 DOI: 10.1023/b:rian.0000005929.21712.78] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
This research explores public judgments about the threat-reducing potential of experts, individual behavior, and government spending. The data are responses of a national sample of 1225 to mail surveys that include measures of several dimensions of public judgments about violent crime, automobile accidents, hazardous chemical waste, air pollution, water pollution, global warming, AIDS, heart disease, and cancer. Beliefs about who can best mitigate threats are specific to classes of threats. In general, there is little faith that experts can do much about violent crime and automobile accidents, moderate faith in their ability to address problems of global warming, and greater expectations for expert solutions to the remaining threats. People judge individual behavior as effective in reducing the threats of violent crime, AIDS, heart disease, and automobile accidents but less so for the remaining threats. Faith in more government spending is highest for AIDS and the other two health items, lowest for the trio of violent crime, automobile accidents, and global warming, and moderate for the remaining threats. For most threats, people are not distributed at the extremes in judging mitigators. Strong attitudinal and demographic cleavages are also lacking, although some interesting relationships occur. This relative lack of sharp cleavages and the generally moderate opinion indicate ample opportunity for public education and risk communication.
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