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101.
E H Chung A E Hutcheon N C Joyce J D Zieske 《Investigative ophthalmology & visual science》1999,40(9):1952-1958
PURPOSE: This study's intention was to examine the progression of ocular surface epithelium through the G1/S transition of the cell cycle after corneal epithelial debridement. METHODS: Three-millimeter debridements were made in central rat cornea and allowed to heal 4 to 48 hours in vivo. Unwounded contralateral eyes served as controls. Two hours before the animals were killed, 5-bromo-2-deoxyuridine (BrdU) was injected to detect S-phase cells. Incorporated BrdU was visualized by indirect immunofluorescence microscopy, and expression of G1 cell-cycle markers cyclins D and E was examined by indirect immunofluorescence and immunoblotting. RESULTS: The number of BrdU-labeled cells in conjunctival, limbal, and peripheral epithelium peaked at 28 hours after wounding (3.9-, 4.5-, and 3.2-fold increases, respectively). In unwounded eyes, cyclin D showed diffuse cytoplasmic localization with occasional basal cells exhibiting a nuclear localization, while anti-cyclin E showed intense localization in limbal and conjunctival basal cells but only minimal labeling in corneal epithelium. Within 8 to 12 hours after wounding, the nuclei of most corneal basal cells outside the wound area were bound intensely by anti-cyclins D and E. Immunoblotting revealed that cyclin D and E protein levels increased 4.5- and 12.1-fold after wounding, respectively. Epithelium migrating into the wound area did not incorporate BrdU and did not exhibit nuclear localization of cyclins D and E. CONCLUSIONS: Corneal epithelial debridement stimulates basal cells outside the wound area to synchronously enter the cell cycle. However, cells migrating to cover the wound area do not progress through the cell cycle. These data suggest a compartmentalization of the proliferative and migratory phases of wound repair. 相似文献
102.
Monoamine oxidase-dependent metabolism of dopamine in the striatum and substantia nigra of
Donato A. Di Monte Louis E. DeLanney Ian Irwin Joyce E. Royland Piu Chan Michael W. Jakowec J. William Langston 《Brain research》1996,738(1)
The effects of monoamine oxidase (MAO) inhibitors on the metabolism of dopamine synthesized from exogenous
-DOPA were investigated in the striatum and substantia nigra of squirrel monkeys. Administration of a single dose of
-DOPA (methyl ester, 40 mg/kg, i.p.) caused a significant increase in the levels of dopamine, 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) and in the DOPAC/dopamine ratio in the putamen, caudate and substantia nigra. These changes were more pronounced in the substantia nigra than in the striatum and within the striatum of
-DOPA-treated monkeys, levels of dopamine and its metabolites were higher in the putamen than in the caudate nucleus. When
-DOPA treatment was preceded by the injection of clorgyline or deprenyl at a concentration (1 mg/kg) which selectively inhibited MAO A or MAO B, respectively, striatal dopamine was increased while the striatal DOPAC and HVA levels and DOPAC/dopamine ratio were significantly reduced as compared to the values obtained with
-DOPA alone. The two MAO inhibitors also counteracted the increase in the DOPAC and HVA levels and DOPAC/dopamine ratio induced by
-DOPA in the substantia nigra. Thus, both MAO A and MAO B contribute to the metabolism of dopamine when higher levels of this neurotransmitter are generated from
-DOPA in the squirrel monkey. The extent of reduction of dopamine catabolism (as assessed by the decrease in DOPAC and HVA levels) in the striatum and substantia nigra was similar with clorgyline and deprenyl even if the ratio MAO A/MAO B was approximately 1 to 10. This indicates that, though catalyzed by both MAO A and MAO B, dopamine deamination following treatment with
-DOPA preferentially involves MAO A. 相似文献
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103.
Frances Conway Lester A. H. Critchley Joyce C. Stuart Ross C. Freebairn 《Journal canadien d'anesthésie》1996,43(1):23-29
Purpose
To study the haemodynamic effects of intrathecal meperidine, administered either alone or mixed with bupivacaïne.Methods
We studied 42 Chinese patients, aged 59–87 yr, scheduled for transurethral bladder or prostate surgery, randomized into three equals groups, that received either meperidine 0.8 mg · kg?1 meperidine 0.4 mg · kg?1 plus 1.5 ml of 0.5% heavy bupivacaïne or 3 ml of heavy bupivacaïne 0.5%. Non-invasive systolic (SAP) and mean (MAP) arterial pressures, central venous pressure and cardiac index, stroke index and heart rate (HR) measured by the BoMed NCCOM3-R7S bioimpedance device, were recorded over the first 25 min. Systemic vascular resistance index (SVRI) was derived. Onset of sensory and motor block was also measured. Decreases in MAP of 25% were treated with colloid and metaraminol. Results: The onset of block was slower in the meperidine group (P < 0.05). Decreases in SAP, MAP and SVRI (all; P < 0.001) occurred within five minutes in all three groups. The HR was increased in the bupivacaïne group (P = 0.03), but bradycardias treated with atropine occurred in six patients receiving meperidine and four patients receiving the mixture. Six patients receiving meperidine and two patients receiving the mixture required general anaesthesia for inadequate block. The incidence of nausea and vomiting was higher in the patients receiving meperidine (P < 0.05). No other complications were encountered.Conclusions
Intrathecal meperidine used alone or mixed with bupivacaïne has no intra-operative advantage over heavy bupivacaïne 0.5%. 相似文献104.
105.
106.
James S. Young Ray L. Buschbom James M. Gurtisen Stephen P. Joyce 《Archives of environmental contamination and toxicology》1979,8(1):97-106
Three experiments with a sabellid polychaete (Eudistylia vancouveri) show the threshold concentration for increasing copper accumulation with time to lie between 3 and 6 g/L total copper in seawater during winter conditions. The branchial crown, probably the major absorptive site, concentrated more copper than the body. Accumulation was influenced by size but not by sex. Our studies indicate that the body burden of copper will increase above natural levels in areas of industrial discharge where copper levels are above the threshold limit for accumulation. 相似文献
107.
Mrs. Joyce K. Laben R.N. M.S. J.D. Ms. Lona Davis Spencer M.A. 《Community mental health journal》1976,12(4):405-414
Decentralization of mental health services to persons in contact with the criminal justice system is essential in the application of community mental health concepts. This is feasible considering the levels of "dangerousness" of such persons, costs of the typical isolated central facility, and implications of the Supreme Court decision Jackson v. Indiana (406 U.S. 715, 1972). In Tennessee, reform began with legal review of unit records, pretrial screening in mental health centers, revision of state law, liaison with the Tennessee Board of Pardons and Paroles, and use of consultant staff. The results are positive wherever decentralization of services has been maintained. 相似文献
108.
Raymond T Bartus Dwaine F Emerich Joyce Hotz Marc Blaustein Reginald L Dean Brigido Perdomo Anthony S Basile 《Neuropsychopharmacology》2003,28(11):1973-1982
While oral naltrexone is effective in treating alcohol and opiate dependencies, poor patient adherence and widely fluctuating plasma levels limit its efficacy. To overcome these problems, an extended-release formulation of naltrexone (Vivitrex) was developed by encapsulating naltrexone into injectable, biodegradable polymer microspheres. Pharmacokinetic studies in rats demonstrated that this formulation produced stable, pharmacologically relevant plasma levels of naltrexone for approximately 1 month following either subcutaneous or intramuscular injections. While rats receiving placebo microspheres demonstrated a pronounced analgesic response to morphine in the hot-plate test, morphine analgesia was completely blocked in rats treated with extended-release naltrexone. This antagonism began on day 1 following administration and lasted for 28 days. Rats reinjected with extended-release naltrexone 34 days after the initial dose and tested for another 35 days showed consistent suppression of morphine analgesia for an additional 28 days. mu-Opioid receptor density, as measured by [(3)H]DAMGO autoradiography, increased up to two-fold following a single injection of extended-release naltrexone. Saturation binding assays using [(3)H]DAMGO showed changes in the midbrain and striatum at 1 week after extended-release naltrexone administration, and after 1 month in the neocortex. These receptor increases persisted for 2-4 weeks after dissipation of the morphine antagonist actions of naltrexone. These data suggest that therapeutically relevant plasma levels of naltrexone can be maintained using monthly injections of an extended-release microsphere formulation, and that changes in mu-opioid receptor density do not impact its efficacy in suppressing morphine-induced analgesia in the rat. Clinical trials of extended release naltrexone for treating alcohol and opiate dependency are currently ongoing. 相似文献
109.
Garrett C Durkan Joyce E Nutt Colin Marsh Paul H Rajjayabun Mary C Robinson David E Neal John Lunec J Kilian Mellon 《Clinical cancer research》2003,9(7):2576-2582
PURPOSE: The purpose is to assess the prognostic significance of matrix metalloproteinase (MMP)-9 in patients with bladder cancer using a combination of ELISA (to measure MMP-9 in voided urine) and immunohistochemistry (to study MMP-9 in bladder tumors). The relationship between MMP-9 and its principal inhibitor, tissue inhibitor of metalloproteinase (TIMP)-1 (in voided urine samples) was also studied. EXPERIMENTAL DESIGN: A total of 134 patients with bladder tumors (7 cis, 76 T(a), 27 T(1), 24 T(2)-T(4); 40 G1, 43 G2, and 44 G3), 33 patients with benign urological conditions, and 36 healthy volunteers was studied. Samples from 106 patients with bladder cancer and 12 controls were stained for MMP-9. Clinical follow-up data were available on 116 patients (median: 25 months; range: 4-36 months). RESULTS: MMP-9 was present in all urine samples analyzed. There were no differences between patients with cancer and patients with benign disorders. However, patients had significantly higher urinary MMP-9 than normal volunteers (P = 0.0167). Urinary MMP-9 was associated with bladder tumors of advanced stage (P = 0.0065) and large size (P < 0.0001) but not with grade (P = 0.14), multiplicity (P = 0.31), recurrence (P = 0.55), progression (P = 0.83), or survival (P = 0.55). Low MMP-9:TIMP-1 ratios in patients with nonmuscle-invasive tumors were associated with higher recurrence rates (P = 0.0035). Sixty percent (64 of 106) of bladder tumor specimens expressed MMP-9 compared with none of 12 normal urothelial biopsies (P < 0.0001). MMP-9 staining was associated with tumor size (P = 0.014), disease progression (P = 0.005), and poor disease-specific survival (P = 0.022) but was unrelated to tumor stage (P = 0.46), grade (P = 0.26), multiplicity (P = 0.85), or recurrence rate (P = 0.62). CONCLUSIONS: High urinary MMP-9 levels are associated with large bladder tumors. A low urinary MMP-9:TIMP-1 ratio may indicate a higher risk of intraluminal nonmuscle-invasive tumor recurrence and may assist in planning follow-up surveillance protocols. 相似文献
110.