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61.
D. M. Erickson S. E. Harris D. D. Dean M. A. Harris J. M. Wozney B. D. Boyan Z. Schwartz 《Journal of orthopaedic research》1997,15(3):371-380
This study examined the effect of recombinant human bone morphogenetic protein-2 on several parameters of growth, differentiation, and matrix synthesis and on the endogenous production of mRNA of bone morphogenetic proteins 2 and 4 by growth plate chondrocytes in culture. Chondrocytes from resting and growth zones were obtained from rat costochondral cartilage and cultured for 24 or 48 hours in medium containing 0.05-100 ng/ml recombinant human bone morphogenetic protein-2 and 10% fetal bovine serum. Incorporation of [3H]thymidine, cell number, alkaline phosphatase specific activity, incorporation of [3H]proline into collagenase-digestible protein and noncollagenase-digestible protein, and incorporation of [35S]sulfate were assayed as indicators of cell proliferation, differentiation, and extracellular matrix synthesis. mRNA levels T for bone morphogenetic proteins 2 andv4 were determined by Northern blot analysis. Recombinant human bone morphogenetic protein-2 increased the incorporation of [3H]thymidine by quiescent resting-zone and growth-zone cells in a similar manner, whereas it had a differential effect on nonquiescent cultures. At 24 and 48 hours, 12.5-100 ng/ml recombinant human bone morphogenetic protein-2 caused a dose-dependent increase in cell number and DNA synthesis in resting-zone chondrocytes. No effect was seen in growth-zone cell Recombinant human bone morphogenetic protein-2 stimulated alkaline phosphatase specific activity in resting-zone chondrocytes in a bimodal manner, causing significant increases between 0.2 and 0.8 ng/ml and again between 25 and 100 ng/ml. In contrast, alkaline phosphatase specific activity in growth-zone chondrocytes was significantly increased only between 12.5 and 100 ng/ml. Recombinant human bone morphogenetic protein-2 increased the production of both collagenase-digestible protein and noncollagenase-digestible protein by resting-zone and growth-zone cells, but incorporation of [35S]sulfate was unaffected. Administration of recombinant human bone morphogenetic protein-2 also increased incorporation of [3H]uridine in both resting-zone and growth-zone chondrocytes; these cells produced mRNA for bone morphogenetic proteins 2 and 4. Bone morphogenetic protein-2 mRNA levels in both resting-zone and growth-zone chondrocytes increased in the presence of recombinant human bone morphogenetic protein-2; however, bone morphogenetic protein-4 mRNA levels in growth-zone cells decreased under its influence, and those in resting-zone cells were upregulated only with a dose of 10 ng/ml. This indicates that recombinant human bone morphogenetic protein-2 regulates chondrocyte proliferation, differentiation, and matrix production, and the effects are dependent on the stage of cell maturation. Resting-zone chondrocytes were more sensitive, suggesting that they are targeted by bone morphogenetic protein-2 and that this growth factor may have autocrine effects on these cells. 相似文献
62.
S W Wise K D Hopper T A Schwartz T R Ten Have C J Kasales 《AJNR. American journal of neuroradiology》1997,18(3):401
PURPOSETo evaluate scanning parameters (conventional versus spiral CT, section thickness, and pitch) and vessel orientation in the performance of CT angiography.METHODSConventional CT and 1.0-, 1.5-, and 2.0-pitch spiral CT acquisitions of a carotid phantom designed with vessels oriented parallel to the z-axis, 45 degrees oblique, and perpendicular to the z-axis were obtained with section thicknesses of 2, 4, and 8 mm. The phantom contained 32 vessels with 0% to 100% stenoses. Normal and stenotic luminal diameters were measured and the number of artifacts was assessed.RESULTSNo overall difference was observed among conventional and spiral CT acquisitions obtained with pitches of 1.0, 1.5, and 2.0. With thicker sections, CT angiographic accuracy decreased and artifacts increased. The three-vessel orientations were relatively comparable in accuracy in terms of the percentage of stenosis measured. Vessels parallel to the z-axis suffered less artifactual degradation. Unique artifacts, such as luminal distortion and beam hardening, were observed in vessels oriented at 45 degrees and perpendicular to the z-axis.CONCLUSIONUse of thinner sections with vessels oriented parallel to the z-axis optimizes CT angiographic quality. There is no apparent degradation with the use of spiral CT, and a pitch of 1.5 or 2.0 provides results equivalent to 1.0-pitch spiral studies. 相似文献
63.
Interleukin-2 and granulocyte-macrophage colony-stimulating factor stimulate growth of a virulent strain of Escherichia coli. 总被引:2,自引:2,他引:0 下载免费PDF全文
The effect of human recombinant interleukin-2 (IL-2) and human recombinant granulocyte-macrophage colony-stimulating factor on the growth of a virulent strain of Escherichia coli in tissue culture medium and in untreated, normal mouse serum was investigated. Both of these cytokines enhanced the growth of the microorganism two- to threefold in tissue culture medium with or without additional fetal calf serum and in untreated mouse serum. IL-4 did not have any effect on the growth of this microbe under the conditions tested. That the enhancement of growth seen with recombinant IL-2 was due to the active cytokine was shown by the following data: (i) addition of an antibody to IL-2 abrogated the growth-promoting effect; (ii) the excipient buffer, which contained everything except the active cytokine, was inactive in modifying bacterial growth; and (iii) heat-inactivated recombinant IL-2 did not promote enhanced microbial growth. The enhancement of growth with IL-2 was significant with concentrations as low as 1 U/ml. Growth of an avirulent strain of E. coli was not stimulated by IL-2. Moreover, addition of IL-2 to growth virulent E. coli in tissue culture medium led to rapid removal of the cytokine from the medium. Collectively, these data suggest that cytokines may act as growth factors for some virulent bacteria. 相似文献
64.
O D Hensens J M Liesch D L Zink J L Smith C F Wichmann R E Schwartz 《The Journal of antibiotics》1992,45(12):1875-1885
Pneumocandin B0 (6) and six related lipopeptides are antifungal and anti-Pneumocystis carinii agents from mutants of Zalerion arboricola, whose structures were determined mainly on the basis of spectroscopic analysis. They belong, along with pneumocandin A0 (L-671,329) previously isolated from these laboratories, to the echinocandin class of antifungal agents. The product from base-catalyzed ring opening involving the hemiaminal position of the dihydroxyornithine residue of B0, has been clearly defined as 6b. Modifications were limited to the 3-hydroxy-4-methylproline, 3,4-dihydroxyhomotyrosine and 4,5-dihydroxyornithine residues of pneumocandin A0. 相似文献
65.
The diffusion of ofloxacin in infected and healthy human and rabbit eyes was investigated. In the human study, cataract surgery patients were given intravenous ofloxacin either as a single 200 or 400 mg dose or as two 400 mg infusions 12 hours apart. Samples of aqueous humor and plasma were collected between 1 and 12 hours after the end of the infusion. Levels in the anterior chamber increased with the dose; peak levels, which occurred after three hours, were 0.33 mg/l after 200 mg and 1.24 mg/l after two 200 mg doses given 12 hours apart. In the rabbit study, 16 hours after experimental infection of the left eye by injection of S. epidermidis into the vitreous, animals were given an intraperitoneal injection of 20 or 50 mg/kg ofloxacin. Dosages in the various ocular tissues showed that penetration into the eye varied with race (albinos greater than pigmented) and dose. Intraocular ofloxacin levels, including in the vitreous, increased two fold when the eye was infected; however, penetration into the sclera, choroid, and retina was comparable in infected and noninfected eyes. These findings in humans and animals suggest that ofloxacin in a dose of a least 400 mg is a useful agent for the treatment of prophylaxis of ocular infections. 相似文献
66.
Further experience with radiation therapy and concomitant intravenous chemotherapy in advanced carcinoma of the lower female genital tract 总被引:4,自引:1,他引:3
William S. Roberts M.D. Mitchel S. Hoffman M.D. John J. Kavanagh M.D. James V. Fiorica M.D. Harvey Greenberg M.D. Michael A. Finan M.D. Denis Cavanagh M.D. 《Gynecologic oncology》1991,43(3):233-236
Sixty-seven patients with advanced carcinoma of the lower female genital tract (cervix, vagina, and vulva) were treated with radiation and concomitant intravenous cisplatin and/or 5-fluorouracil. Fifty-seven patients (85%) responded completely clinically. Thirty-five (61%) complete responders recurred with a median time to recurrence of 6 months. Twenty-six of the thirty-five patients who recurred had some component of local failure. The 22 complete responders who have not recurred have been followed a median of 13 months. Acute toxicity was minimal, with only 6 patients requiring interruption of therapy. Nine (13%) patients developed severe late complications and eight required surgery. The actuarial 5-year survival is 22%. This treatment regimen is disappointing in terms of both survival and local control. 相似文献
67.
Executive function impairments in children with attention-deficit hyperactivity disorder: do they differ between school and home environments? 总被引:1,自引:0,他引:1
Daniela Mares Alan McLuckie Michael Schwartz Michael Saini 《Revue canadienne de psychiatrie》2007,52(8):527-534
OBJECTIVE: The primary purpose of this study was to compare parent and teacher reports of executive function (EF), as measured by the Behavior Rating Inventory of Executive Function (BRIEF), on a sample of children who had been diagnosed with attention-deficit hyperactivity disorder (ADHD). If differences were found, the secondary purpose was to explore these differences by determining which of the 8 BRIEF scales, each representing a different EF, would best predict symptoms of ADHD by the 2 proxy reporters. METHOD: We performed a secondary data analysis on the assessment information pertaining to 240 children, aged 5 to 15 years, accessing services at an urban Toronto psychiatric program specializing in ADHD. We compared parent and teacher ratings and applied logistical binary regressions to predict the probability of a child's meeting the criteria for clinically significant inattention and hyperactivity-impulsivity on the ADHD Rating Scale-IV. RESULTS: As expected, teachers reported more variety and severity of EF impairments than did parents. In addition, teachers used inhibition, organization of materials, and planning and organizing as predictors of ADHD symptoms, whereas parents relied predominantly on inhibition, working memory, and planning and organizing as the risk factors. CONCLUSION: Consistent with the current theory, EF impairments, particularly in inhibition, appear to underlie the behavioural manifestation of ADHD. However, parents and teachers do not always agree when reporting EF impairments at home and in school. Thus information from both types of informants is essential for understanding and treating children with this disorder. 相似文献
68.
69.
Human neutrophils, activated with cytokines or not, do not kill virulent Mycobacterium tuberculosis 总被引:3,自引:0,他引:3
M Denis 《The Journal of infectious diseases》1991,163(4):919-920
70.
Local cerebral glucose metabolic rates in obsessive-compulsive disorder. A comparison with rates in unipolar depression and in normal controls 总被引:5,自引:0,他引:5
L R Baxter M E Phelps J C Mazziotta B H Guze J M Schwartz C E Selin 《Archives of general psychiatry》1987,44(3):211-218
We studied 14 patients with obsessive-compulsive disorder (OCD) by positron emission tomography and the fluorodeoxyglucose method, looking for abnormalities in local cerebral metabolic rates for glucose in brain structures that have been hypothesized to function abnormally in OCD. These patients were compared with 14 normal controls and 14 patients with unipolar depression. The patients with unipolar depression and OCD did not differ in levels of anxiety, tension, or depression. In OCD, metabolic rates were significantly increased in the left orbital gyrus and bilaterally in the caudate nuclei. This was apparent on all statistical comparisons with both controls and unipolar depression. The right orbital gyrus showed at least a trend to an increased metabolic rate in all comparisons. The metabolic rate in the left orbital gyrus, relative to that in the ipsilateral hemisphere (orbital gyrus/hemisphere ratio), was significantly elevated compared to controls and subjects with unipolar depression, and stayed high even with successful drug treatment. Though it was in the normal range in the morbid state, with improvement in OCD symptoms after drug treatment, the caudate/hemisphere metabolic ratio increased uniformly and significantly bilaterally. This ratio did not increase in patients who did not respond to treatment. Thus, OCD showed cerebral glucose metabolic patterns that differed from controls in both the symptomatic and recovered states. 相似文献