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101.
The impact of a cardioprotective protocol on the incidence of cardiac complications after aortic abdominal surgery 总被引:1,自引:0,他引:1
Licker M Khatchatourian G Schweizer A Bednarkiewicz M Tassaux D Chevalley C 《Anesthesia and analgesia》2002,95(6):1525-33, table of contents
We analyzed a local database including 468 consecutive patients who underwent elective aortic abdominal surgery over an 8-yr period in a single institution. A new cardioprotective perioperative protocol was introduced in January 1997, and we questioned whether perioperative cardiac outcome could be favorably influenced by the application of a stepwise cardiovascular evaluation based on the American College of Cardiology/American Heart Association guidelines and by the use of antiadrenergic drugs. Clonidine was administered during surgery, and beta-blockers were titrated after surgery to achieve heart rates less than 80 bpm. We compared data of two consecutive 4-yr periods (1993-1996 [control period] versus 1997-2000 [intervention period]). Implementation of American College of Cardiology/American Heart Association guidelines was associated with increased preoperative myocardial scanning (44.3% vs 20.6%; P < 0.05) and coronary revascularization (7.7% vs 0.8%; P < 0.05). During the intervention period, there was a significant decrease in the incidence of cardiac complications (from 11.3% to 4.5%) and an increase in event-free survival at 1 yr after surgery (from 91.3% to 98.2%). Multivariate regression analysis showed that the combined administration of clonidine and beta-blockers was associated with a decreased risk of cardiovascular events (odds ratio, 0.3; 95% confidence interval, 0.1-0.8), whereas major bleeding, renal insufficiency, and chronic obstructive pulmonary disease were predictive of cardiac complications. In conclusion, cardiac testing was helpful to identify a small subset of high-risk patients who might benefit from coronary revascularization. Sequential and selective antiadrenergic treatments were associated with improved postoperative cardiac outcome. IMPLICATIONS: Implementation of American College of Cardiology/American Heart Association guidelines and use of antiadrenergic drugs were associated with better cardiac outcomes after major vascular surgery. 相似文献
102.
103.
MJ Veness F Foroudi V Gebski I Timms Y Sathiyaseelan B Cakir KW Tiver 《Journal of Medical Imaging and Radiation Oncology》2006,50(5):468-474
Radiation‐induced mucositis is an acute reaction of the mucosa of patients undergoing head and neck radiotherapy. It can have debilitating and dose‐limiting consequences. There is no consensus on an accepted intervention that significantly reduces its severity. Misoprostol is a synthetic prostaglandin E1 analogue, with properties of a mucosal cytoprotectant. We designed a randomized, double‐blind, placebo‐controlled trial of misoprostol in patients with head and neck cancer. The aim of this study was to determine if topical misoprostol was effective in reducing the severity of radiation‐induced mucositis in patients receiving radical dose radiotherapy. The effect of this intervention on a patient’s general well‐being was also investigated. The primary end‐point of the study was the incidence of Radiation Therapy Oncology Group grade 3 mucositis. Between 1999 and 2002, 83 patients were recruited into the study at Westmead and Nepean Hospitals, Sydney. Forty‐two patients were randomized to receive misoprostol and 41 to receive a placebo. Most patients received radiotherapy in the adjuvant setting (52 of the 83) and had either an oral cavity (42 of the 83) or an oropharyngeal (16 of the 83) cancer. We could not identify any significant difference in the incidence of severe mucositis based on whether patients were allocated to receive misoprostol or placebo. There was no significant difference in the mean area under the mucositis curve (13.2 vs 16.6; P = 0.1). Patients allocated to misoprostol did report slightly increased soreness (7.6 vs 6.9; P = 0.04) and a greater use of analgesics. However, this difference did not translate into a worse feeling of general well‐being as measured by a simple visual analogue scale (5.8 vs 5.2; P = 0.3). In conclusion, we were unable to identify a reduction in radiation‐induced mucositis in patients receiving misoprostol. There is a paucity of high‐level evidence on potentially useful interventions and a continued need for new and innovative research, incorporating quality‐of‐life measurements, in patients experiencing radiation‐induced mucositis. 相似文献
104.
GM Thambugala A Mohamed GFA O Neill MJ Fulham 《Journal of Medical Imaging and Radiation Oncology》2006,50(6):604-606
We present the FDG PET‐CT findings in a patient with persistent pain 7 weeks after a nephrectomy and lymph node dissection for a sarcomatoid renal cell carcinoma. Although conventional imaging was unable to detect evidence of metastatic spread outside the para‐aortic nodes, a PET‐CT scan showed unexpected extensive dissemination. Currently, there are no reports in the literature of the PET‐CT findings in sarcomatoid renal cell carcinomas. 相似文献
105.
随着禽流感病毒H5N1的不断蔓延,越来越有可能发生人类流感的大流行。如果现在发生流感的大流行,不仅还没有有效的疫苗,而且还可能造成抗病毒药物的缺乏。目前尚没有证据表明抗流感药物神经氨酸酶抑制剂(neuraminidaseinhibitor对)禽流感和流感大流行的病毒有效,给予神经氨酸酶抑制剂后,感染H5N1禽流感病毒的患者的死亡率仍然很高。而且流感病毒的耐药会进一步限制抗病毒药物的疗效。假如继发性细菌感染是流感常见且重要的致命性并发症,那么抗生素在人类流感大流行中将占有重要的一席地位。 相似文献
106.
Spiliopoulos A de Perrot M Licker M Murith N Robert J 《Scandinavian cardiovascular journal : SCJ》2000,34(1):92-94
Bronchopleural fistula after pneumonectomy is a dreaded complication, because of its high morbidity and mortality. We describe a successful technique using closed-chest irrigation of the pleural cavity continued with transposition of a latissimus dorsi island flap. 相似文献
107.
A striking difference between two structurally related anti-estrogen
medicines is that tamoxifen is strongly hepatocarcinogenic in the rat,
whereas toremifene lacks such activity. To study the basis for this
difference, the initiating potential of tamoxifen and toremifene were
studied by measurement of rapid induction of hepatocellular altered foci
(HAF) that express placental-type glutathione S-transferase in the livers
of female Sprague-Dawley (S-D) rats and female Fischer 344 (F344) rats.
Both agents were administered by gavage at equimolar doses up to a dose
that produced marked weight gain suppression. In rats given the high dose
of 40 mg/kg per day tamoxifen continuously for 36 weeks, 75% of S-D rats
developed liver neoplasms, in contrast to only 10% of F344 rats. In the S-D
strain, tamoxifen produced a tendency to increased HAF at 2 weeks at the
dose of 40 mg/kg per day and by 12 weeks, a dose-related increase was
evident. In contrast, toremifene induced no HAF even at the equimolar high
dose of 42.4 mg/kg per day for 12 weeks. The induction of HAF by tamoxifen
was less in the F344 rats. Neither agent elicited increases in
hepatocellular proliferation in S-D or F344 rats. When phenobarbital was
administered for 24 weeks as a promoting agent after the anti-estrogens,
S-D rats given tamoxifen at 20 mg/kg per day for 12 weeks, developed liver
neoplasms, but not F344 rats or rats of either strain given even a higher
dose (42.4 mg/kg) of toremifene. Thus, tamoxifen has initiating activity in
these rat strains whereas toremifene does not.
相似文献
108.
The Syrian hamster embryo (SHE) cell system was used to evaluate the
ability of two hepatocarcinogenic structurally related peroxisome
proliferators (PPs) to induce morphological transformation (MT) of SHE
colonies and to inhibit gap junctional intercellular communication (GJIC).
Clofibrate and methyl clofenapate (MCP), which was shown to be a more
active PP and a more potent carcinogen in vivo than clofibrate, were
compared. MCP appeared slightly more active in vitro than clofibrate in
affecting MT and GJIC of SHE cells. The morphological transformation of SHE
colonies was induced by 50 microM MCP, against 100 microM clofibrate.
Moreover, 50 microM MCP potentiated the transforming effects of both
benzo[a]pyrene and 12-O- tetradecanoylphorbol-13-acetate. The inhibition of
GJIC, measured by transfer of lucifer yellow, was transient and occurred at
concentrations inducing morphological transformation. MCP inhibited dye
transfer at 50 microM and the inhibition lasted up to 24 h at 100 microM.
Inhibition of communication lasted only 4 h with clofibrate and occurred at
a higher concentration (175 microM). This study showed that both the SHE
cell transformation and dye transfer assays were able to display the
different activities of the two PPs, even though the difference in potency
observed was smaller than in vivo. It also revealed interactions between
non-genotoxic carcinogens and the ability of the SHE cell transformation
assay to detect these combined effects.
相似文献
109.
Porter DW; Yakushiji H; Nakabeppu Y; Sekiguchi M; Fivash MJ Jr; Kasprzak KS 《Carcinogenesis》1997,18(9):1785-1791
The toxicity of Ni(II), Co(II) and Cu(II) in animals, and that of Cd(II) in
cultured cells, has been associated with generation of the promutagenic
lesion 8-oxo-7,8-dihydroguanine (8-oxoguanine) in DNA, among other effects.
One possible source of this base may be 8-oxo-7,8-
dihydro-2'-deoxyguanosine-5'-triphosphate (8-oxo-dGTP), a product of
oxidative damage to the nucleotide pool, from which it is incorporated into
DNA. To promote such incorporation, the metals would have to inhibit
specific cellular 8-oxo-dGTPases that eliminate 8-oxo-dGTP from the
nucleotide pool. The present study was designed to test such inhibition in
vitro on 8-oxo-dGTPases from two different species, the human MTH1 protein
and Escherichia coli MutT protein. In the presence of Mg(II), the natural
activator of 8-oxo-dGTPases, all four metals were found to inhibit both
enzymes. For MTH1, the IC50 values (+/- SE; n = 3-4) were 17 +/- 2 microM
for Cu(II), 30 +/- 8 microM for Cd(II), 376 +/- 71 microM for Co(II) and
801 +/- 97 microM for Ni(II). For MutT, they were 60 +/- 6 microM for
Cd(II), 102 +/- 8 microM for Cu(II), 1461 +/- 96 microM for Ni(II) and 8788
+/- 1003 microM for Co(II). Thus, Cu(II) and Cd(II) emerged as much
stronger inhibitors than Ni(II) and Co(II), and MTH1 appeared to be
generally more sensitive to metal inhibition than MutT. Interestingly, in
the absence of Mg(II), the activity of the enzymes could be restored by
Co(II) to 73% of that with Mg(II) alone for MutT, and 34% for MTH1, the
other metals being much less or non-effective. The difference in
sensitivity to metal inhibition between the two enzymes may reflect the
differences in the amino acid ligands, especially the cysteine ligand,
outside their evolutionarily conserved Mg(II)-binding active sites, which
might indicate predominantly non-competitive or uncompetitive mechanism of
the inhibition. The overall results suggest that inhibition of 8-oxo-
dGTPases may be involved in the mechanisms of induction of the 8-
oxoguanine lesion in DNA by the metal ions studied, especially the non-
redox-active Cd(II) cation.
相似文献
110.
Increased risk of leukaemia in patients with juvenile chronic arthritis treated with chlorambucil 总被引:2,自引:0,他引:2
MJ Kauppi HA Savolainen V-J Anttila HA Isomäki 《Acta paediatrica (Oslo, Norway : 1992)》1996,85(2):248-250
Two cases of acute leukaemia have developed in a group of 77 patients treated with chlorambucil (Chl) because of severe juvenile chronic arthritis. The total follow-up from the beginning of Chl treatment in these patients was 560 years, indicating a highly increased risk of leukaemia. Despite favourable results, especially in patients with secondary amyloidosis, Chl should only be used in selected cases. 相似文献