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101.
102.
Smythe  JS; Spring  FA; Gardner  B; Parsons  SF; Judson  PA; Anstee  DJ 《Blood》1995,85(10):2929-2936
This report describes the production and characterization of 13 rodent monoclonal antibodies to the human erythrocyte anion transport protein AE1 (syn. band 3). Eleven antibodies (4 murine and 7 rat) recognize epitopes dependent on the integrity of the third extracellular loop of the protein. Two antibodies (1 murine and 1 rat) recognize epitopes on the N-terminal cytoplasmic domain. Quantitative binding studies using radioiodinated IgG and Fab fragments of antibodies to extracellular epitopes on AE1 ranged from 77,000 to 313,000 (IgG) and from 241,000 to 772,000 (Fab) molecules bound at saturation. The results indicate that the epitopes recognized by different antibodies vary in their accessibility and suggest that there is heterogeneity in the organization of individual AE1 molecules in the red blood cell membrane. Quantitative binding studies on South East Asian ovalocytes using several antibodies to AE1 and an anti-Wrb show a marked reduction in the number of antibody molecules bound at saturation. These results are consistent with the existence of highly cooperative interactions between transmembrane domains of AE1 in normal erythrocytes and the disruption of these interactions in the variant AE1 found in South East Asian ovalocytes.  相似文献   
103.
Maternally administered recombinant human granulocyte colony- stimulating factor (rhG-CSF) has been shown to cross the placenta and induce a peripheral neutrophilia and increases in the marrow and spleen neutrophil storage pools in fetal and newborn rats. In the present study, we have used this model system to investigate the efficacy of prenatally administered rhG-CSF on neonatal defense to a lethal challenge with Group B-beta hemolytic Streptococcus (GBS). Pregnant rats were injected with rhG-CSF twice daily beginning 6 days before parturition. At birth, all pups were infected with a dose of GBS that is lethal for 90% of infected pups (LD90). Survival was monitored daily for 5 days. Survival of infected pups from saline-treated mothers beyond 60 hours after infection was 10%. No difference in survival was observed among pups from mothers treated 2 and 4 days before parturition. In contrast, we determined that survival was 82.5% among infected pups from mothers treated for 6 days before parturition with rhG-CSF. Our results demonstrate that maternal administration of rhG- CSF augments neonatal defenses against a lethal bacterial challenge.  相似文献   
104.
The hydrogen breath test was performed by ingestion of 20 g lactulose and analysis of end-expiratory air. Eighteen patients undergoing colonoscopy, 17 receiving antibiotics, 12 prepared for colon surgery, and 15 controls were examined. The test was repeated under control conditions in the treated patients. Eleven of 55 subjects failed to produce significant amounts of hydrogen under control conditions. This 20% proportion of non-hydrogen producers is much higher than that reported by other investigators. The hydrogen production was very markedly depressed after preparation for colonscopy and antibiotic therapy. The effect of neomycin and enemata as used in preparation for colon surgery was less marked. Hydrogen production by the colonic flora is thus subject to individual variations and may be affected by various therapeutic regimens. All these may cause false negative results when using the hydrogen breath test to evaluate carbohydrate absorption. The test should therefore not be performed for a considerable time after therapeutic manipulation of the colonic flora.  相似文献   
105.
ObjectivesThis study evaluated the physiologic characteristics of discordant lesions between instantaneous wave-free ratio (iFR) and fractional flow reserve (FFR) and the prognosis at 5 years.BackgroundFFR or iFR have been standard methods for assessing the functional significance of coronary artery stenosis. However, limited data exist about the physiologic characteristics of discordant lesions and the prognostic implications resulting from these lesions.MethodsA total of 840 vessels from 596 patients were classified according to iFR and FFR; high iFR–high FFR (n = 580), low iFR–high FFR (n = 40), high iFR–low FFR (n = 69), and low iFR–low FFR (n = 128) groups, which were compared with a control group (n = 23). The differences in coronary circulatory indices including the coronary flow reserve (CFR), index of microcirculatory resistance (IMR), and resistance reserve ratio (RRR) (resting distal arterial pressure × mean transit time / hyperemic distal arterial pressure × hyperemic mean transit time), which reflect the vasodilatory capacity of coronary microcirculation, were compared. Patient-oriented composite outcomes (POCO) at 5 years including all-cause death, any myocardial infarction, and any revascularization were compared among patients with deferred lesions.ResultsIn the low iFR–high FFR group, CFR, RRR, and IMR measurements were similar to the low iFR–low FFR group: CFR 2.71 versus 2.43 (p = 0.144), RRR 3.36 versus 3.68 (p = 0.241), and IMR 18.51 versus 17.38 (p = 0.476). In the high iFR–low FFR group, the CFR, RRR, and IMR measurements were similar to the control group: CFR 2.95 versus 3.29 (p = 0.160), RRR 4.28 versus 4.00 (p = 0.414), and IMR 17.44 versus 17.06 (p = 0.818). Among the 4 groups, classified by iFR and FFR, CFR and RRR were all significantly different, except for IMR. However, there were no significant differences in the rates of POCO, regardless of discordance between the iFR and FFR. Only the low iFR–low FFR group had a higher POCO rate compared with the high iFR–high FFR group (adjusted hazard ratio: 2.46; 95% confidence interval: 1.17 to 5.16; p = 0.018).ConclusionsDifferences in coronary circulatory function were found, especially in the vasodilatory capacity between the low iFR–high FFR and high iFR–low FFR groups. FFR–iFR discordance was not related to an increased risk of POCO among patients with deferred lesions at 5 years. (Clinical, Physiological and Prognostic Implication of Microvascular Status; NCT02186093; Physiologic Assessment of Microvascular Function in Heart Transplant Patients; NCT02798731)  相似文献   
106.
The effects of granulocyte-macrophage colony-stimulating factor (GM- CSF) are not confined to cells of the myeloid lineage. GM-CSF has been shown to have effects on mature T cells and both mature and immature T- cell lines. We therefore examined the GM-CSF responsiveness of murine thymocytes to investigate whether GM-CSF also affected normal immature T lymphocytes. The studies presented here indicate that GM-CSF augments accessory cell (AC)-dependent T-cell receptor (TCR)-mediated proliferation of unseparated thymocyte populations. To identify the GM- CSF responsive cell type, thymic AC and T cells were examined for GM- CSF responsiveness. We found that GM-CSF augmentation of TCR-induced thymocyte proliferation appears to be mediated via augmentation of AC function, and not via direct effects on mature single-positive (SP) thymocytes. Enriched double-negative (DN) thymocytes were also tested for GM-CSF responsiveness. GM-CSF induced the proliferation of adult and fetal DN thymocytes in an AC-independent and TCR-independent single- cell assay. Thus, in contrast to the SP thymocytes, a DN thymocyte population was directly responsive to GM-CSF. GM-CSF therefore may play a direct role in the expansion of DN thymocytes and an indirect role in the expansion of SP thymocytes.  相似文献   
107.
Delay in hematologic recovery after bone marrow transplantation (BMT) can extend and amplify the risks of infection and hemorrhage, compromise patients' survival, and increase the duration and cost of hospitalization. Because current studies suggest that granulocyte- macrophage (GM) colony-stimulating factor (CSF) may potentiate the sensitivity of hematopoietic progenitor cells to G-CSF, we performed a prospective, randomized trial comparing GM-CSF (250 micrograms/m2/d x 14 days) versus sequential GM-CSF x 7 days followed by G-CSF (5 micrograms/kg/d x 7 days) as treatment for primary or secondary graft failure after BMT. Eligibility criteria included failure to achieve a white blood cell (WBC) count > or = 100/microL by day +21 or > or = 300/microL by day +28, no absolute neutrophil count (ANC) > or = 200/microL by day +28, or secondary sustained neutropenia after initial engraftment. Forty-seven patients were enrolled: 23 received GM-CSF (10 unrelated, 8 related allogeneic, and 5 autologous), and 24 received GM- CSF followed by G-CSF (12 unrelated, 7 related allogeneic, and 5 autologous). For patients receiving GM-CSF alone, neutrophil recovery (ANC > or = 500/microL) occurred between 2 and 61 days (median, 8 days) after therapy, while those receiving GM-CSF+G-CSF recovered at a similar rate of 1 to 36 days (median, 6 days; P = .39). Recovery to red blood cell (RBC) transfusion independence was slow, occurring 6 to 250 days (median, 35 days) after enrollment with no significant difference between the two treatment groups (GM-CSF: median, 30 days; GM-CSF+G- CSF; median, 42 days; P = .24). Similarly, platelet transfusion independence was delayed until 4 to 249 days (median, 32 days) after enrollment, with no difference between the two treatment groups (GM- CSF: median, 28 days; GM-CSF+G-CSF: median, 42 days; P = .38). Recovery times were not different between patients with unrelated donors and those with related donors or autologous transplant recipients. Survival at 100 days after enrollment was superior after treatment with GM-CSF alone. Only 1 of 23 patients treated with GM-CSF died versus 7 of 24 treated with GM-CSF+G-CSF who died 16 to 84 days (median, 38 days) after enrollment, yielding Kaplan-Meier 100-day survival estimates of 96% +/- 8% for GM-CSF versus 71% +/- 18% for GM-CSF+G-CSF (P = .026). These data suggest that sequential growth factor therapy with GM-CSF followed by G-CSF offers no advantage over GM-CSF alone in accelerating trilineage hematopoiesis or preventing lethal complications in patients with poor graft function after BMT.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
108.

Objectives

To compare outcomes and rates of optimal stent placement between optical coherence tomography (OCT) and intravascular ultrasound (IVUS) guided percutaneous coronary intervention (PCI).

Background

Unlike IVUS‐guided PCI, rates of clinical outcomes and optimal stent placement have not been well characterized for OCT‐guided PCI.

Methods

The study enrolled 290 patients who underwent implantation of a second generation drug eluting stent under OCT (122 patients) or IVUS (168 patients) guidance. The two groups were compared after adjusting for baseline differences using 1:1 propensity score matching (PSM) (114 patients in each group). Optimal stent placement was defined as achieving an adequate lumen (optimal minimum stent area [MSA > 4.85 mm2 for OCT, >5 mm2 for IVUS] or a final MSA ≥ 90% of the distal reference lumen area, without edge dissection, incomplete stent apposition, or tissue prolapse), or otherwise performing additional interventions to address suboptimal post‐stenting OCT or IVUS findings. The primary endpoint was one‐year cumulative incidence of major adverse cardiac events (MACE; cardiac death, myocardial infarction and target lesion revascularization). Definite or probable stent thrombosis (ST) rates were evaluated.

Results

In adjusted comparisons between OCT and IVUS groups, there was no significant difference in rates of MACE (3.5% vs. 3.5%, P = 1.000) and ST (0% vs. 0.9%, P = 1.000) at 1 year, optimal stent placement (89.5% vs. 92.1%, P = 0.492), and further intervention (7.9% vs.13.2%, P = 0.234), despite OCT significantly more frequently detecting tissue prolapse (97.4% vs. 47.4%, P < 0.001), and numerically more edge dissection (10.5% vs. 4.4%, P = 0.078) or incomplete stent apposition (48.2% vs. 36.8%, P = 0.082).

Conclusions

OCT guidance showed comparable results to IVUS in mid‐term clinical outcomes, suggesting that OCT can be an alternative tool for stent placement optimization. (J Interven Cardiol 2016;29:216–224)
  相似文献   
109.

Objective

The aim of this study is to evaluate the clinical results of endoscopic radiofrequency ablation of medial branch in patients with chronic low back pain originating from facet joints.

Methods

Between October 2010 and December 2013, 52 consecutive patients had suffering from chronic low back pain had undergone endoscopic radiofrequency denervation of medial branch of dorsal ramus. The clinical outcomes of these 52 patients were reviewed retrospectively. Preoperative and postoperative Visual Analogue Scale (VAS) and Korean version of Oswestry Disability Index (K-ODI), and patients'' satisfaction with the procedure were assessed.

Results

The pain scores on the VAS for back pain had improved significantly from a preoperative mean of 7.1 to a postoperative mean of 2 at the last follow-up (p<0.001). The clinical outcomes based on the K-ODI had also improved significantly from a preoperative mean of 26.5% to postoperative mean of 7.7% at the last follow-up (p<0.001). 80% of patients were satisfied with the procedure. There were no complications associated with the procedure.

Conclusion

Our preliminary results demonstrate that endoscopic radiofrequency denervation of medial branch could be an effective alternative treatment modality for chronic back pain originating from facet joints that provides long-term pain relief.  相似文献   
110.

Background

Fever is a common finding after primary percutaneous coronary intervention (PPCI) in patients with ST-segment elevation myocardial infarction (STEMI). However, its prognostic value is not validated yet.

Objectives

This study sought to evaluate the impact of fever after PPCI in STEMI on adverse clinical outcomes.

Methods

Five hundred fourteen consecutive patients who underwent PPCI due to STEMI were enrolled. Body temperature (BT) was checked every 6 h for 5 days after PPCI. Patients were divided into two groups according to the highest quartile of peak BT; peak BT ≤ 37.6 °C (control group) and peak BT > 37.6 °C (fever group). Rates of 1-year major adverse cardiovascular events (MACE; death, myocardial infarction, any revascularization) were compared.

Results

The prevalence of fever group (peak BT > 37.6 °C) was 24.7% (127/514). White blood cell count, highly sensitive C-reactive protein and serum cardiac troponin I level were higher in fever group than control group (12,162 ± 4199/μL vs. 10,614 ± 3773/μL, p < 0.001; 22.9 ± 49.4 mg/L vs. 7.4 ± 2.5 mg/L, p = 0.001, 16.7 ± 36.9 ng/dl vs. 8.70 ± 26.2 ng/dl, p = 0.027, respectively). The frequency of a history of previous myocardial infarction and left ventricular ejection fraction was lower in fever group (0.0% vs. 4.7%, p = 0.010; 47 ± 8 % vs. 49 ± 9 %, p = 0.002, respectively). There was no significant difference in angiographic characteristics between 2 groups. 1-year MACE rates were higher in fever group (11.0% vs. 4.7%, p = 0.010). Multivariate analysis revealed fever (OR 2.358, 95% CI 1.113–4.998, p = 0.025), diabetes mellitus as risk factor (2.227, 1.031–4.812, 0.042), and left anterior descending artery as infarct related artery (2.443, 1.114–5.361, 0.026) as independent predictors for 1-year MACE.

Conclusions

Fever after PPCI in patients with STEMI is frequently developed and it can predict adverse clinical outcome.  相似文献   
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