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721.
We report a case of ischemic neuropathy of the sciatic nerve in a patient with an anterior column fracture of the acetabulum operated by ilioinguinal approach. It resulted from occlusion of the blood supply to the sciatic nerve. There were no signs of a vascular insult until ischemic changes ensued on the 6th postoperative day on the lateral part of great toe. The patient underwent crossover femoro-femoral bypass grafting and there was a complete reversal of the ischemic changes at 6 months. The sciatic nerve palsy continued to recover until the end of 1 year; by which time the only deficit was a Grade 4 power in the extensor hallucis longus (EHL) and the extensor digitorum longus (EDL). There was no further recovery at 2 years followup.  相似文献   
722.

Introduction

The aim of this retrospective study was to determine the clinical significance of incidental findings detected on positron emission tomography (PET) in patients undergoing staging of oesophagogastric malignancies.

Methods

Patients with oesophagogastric malignancies who underwent PET between June 2007 and May 2012 were included in the study. PET was performed according to hospital protocol. All imaging was interpreted by two consultant radiologists in nuclear medicine. Incidental findings that were unrelated to the primary malignancy were recorded and patients were recommended to have further investigations (imaging, endoscopy and biopsy).

Results

Overall, 333 patients (240 male, 93 female; mean age: 67 years) with upper gastrointestinal malignancies were eligible for inclusion in the study. Eighty-nine of these patients had PET demonstrating one or more incidental findings. Two patients were found to have a second primary malignancy. One patient had a distant metastasis of his primary cancer and six patients had a premalignant lesion.

Conclusions

In this study, incidental findings were discovered in 26.7% of patients with known oesophagogastric cancer. A second primary cancer or premalignant lesion was found in 8.4% of patients with incidental findings. Patients with these findings should be investigated to rule out further malignancy. There were a high proportion of false positive results in our study. It is recommended that each patient is considered on an individual basis and assessed with simultaneous PET and computed tomography.  相似文献   
723.

Introduction

The surgical Apgar score (SAS) can predict 30-day major complications or death after surgery. Studies have validated the score in different patient populations and suggest it should be used to objectively guide postoperative care. We aimed to see whether using the SAS in a decisive approach in a future randomised controlled trial (RCT) would be likely to demonstrate an effect on postoperative care and clinical outcome.

Methods

A total of 143 adults undergoing general/vascular surgery in 9 National Health Service hospitals were recruited to a pilot single blinded RCT and the data for 139 of these were analysed. Participants were randomised to a control group with standard postoperative care or to an intervention group with care influenced (but not mandated) by the SAS (decisive approach). The notional primary outcome was 30-day major complications or death.

Results

Incidence of major complications was similar in both groups (control: 20/69 [29%], intervention: 23/70 [33%], p=0.622). Immediate admissions to the critical care unit was higher in the intervention group, especially in the SAS 0–4 subgroup (4/6 vs 2/7) although this was not statistically significant (p=0.310). Validity was also confirmed in area under the curve (AUC) analysis (AUC: 0.77).

Conclusions

This pilot study found that a future RCT to investigate the effect of using the SAS in a decisive approach may demonstrate a difference in postoperative care. However, significant changes to the design are needed if differences in clinical outcome are to be achieved reliably. These would include a wider array of postoperative interventions implemented using a quality improvement approach in a stepped wedge cluster design with blinded collection of outcome data.  相似文献   
724.
725.
Kaplan  SS; Zdziarski  UE; Kuhns  DB; Basford  RE 《Blood》1988,71(3):677-683
Hexachlorocyclohexanes (HCCHs) are potent stimulators of polymorphonuclear leukocyte (PMN) oxidative metabolism and of mobilization of calcium from intracellular stores. It was of interest, therefore, to evaluate the effect of HCCHs on PMN orientation and chemotaxis and to determine their effectiveness as chemotaxins. Chemotaxis was evaluated using micro-Boyden chambers, f-actin was quantitated by nitrobenzoxadiazole (NBD)-phallacidin fluorescence, and microtubules were quantitated by observing the concanavalin A (Con A) capping phenomenon. We also evaluated changes in intracellular calcium [Ca2+]i using quin 2 fluorescence. We found that the HCCH isomers were not chemotaxins and that the HCCH isomers that stimulated O2- formation (delta and gamma HCCH) inhibited chemotaxis. This effect was associated with inhibition of orientation. In addition, we found extensive inhibition of both f-actin and Con A cap formation. These effects of HCCH on cell function were associated with marked increases of [Ca2+]i. This work suggests that non-receptor-mediated increases of [Ca2+]i associated with HCCH have divergent effects on cell function and suggests that physiologic responses of PMNs requiring cytoskeletal alterations, such as chemotaxis, depend on the controlled responses of receptor-mediated stimulation.  相似文献   
726.
Clonal origin of human erythro-eosinophilic colonies in culture   总被引:10,自引:0,他引:10  
Nakahata  T; Spicer  SS; Ogawa  M 《Blood》1982,59(4):857-864
We have observed the presence of erythropoietic bursts containing eosinophils and their precursors in methylcellulose culture of human peripheral blood and marrow nucleated cells in the presence of erythropoietin and medium conditioned by phytohemagglutinin-stimulated leukocytes (PHA-LCM). It was possible to identify these bursts (colonies) in situ in methylcellulose culture on the basis of their unique red and black colors. Transmission electron microscopy revealed that the constituent erythroid and eosinophilic cells lay intermixed with each other, and through close intercellular connections formed compact colonies and bursts consisting of several sub-colonies. Differential counts of individual erythro-eosinophil colonies (EEo colonies) revealed only a small percentage of blast cells in most of the colonies. Replating experiments of single EEo colonies yielded only eosinophilic colonies and clusters and erythroid colonies. The clonal nature of the EEo colonies was documented by analysis of Y-chromatin- positive cells in individual EEo colonies derived from cocultures of male and female peripheral blood mononuclear cells. Comparison of conditioned media indicated that PHA-LCM is the best stimulator for EEo colonies. These studies suggest that the differentiation capabilities of the progenitors for EEo colonies are restricted to erythroid and eosinophilic differentiation.  相似文献   
727.
Aukrust  P; Svardal  AM; Muller  F; Lunden  B; Berge  RK; Froland  SS 《Blood》1995,86(4):1383-1391
We have previously shown chronic immune activation and enhanced generation of reactive oxygen species in common variable immunodeficiency (CVI). In the present study, we examined levels of glutathione, the dominant intracellular thiol, that play an important protective role against oxidative and inflammatory stress in plasma and in monocytes and lymphocyte subsets in 20 CVI patients and in 16 healthy controls. CD4+ lymphocytes from CVI patients had significantly lower levels of both total and reduced glutathione as well as a lower ratio of reduced to total glutathione compared with healthy controls. This decrease in glutathione levels in CD4+ lymphocytes was most pronounced in the CD45RA+ subset. Plasma levels of total glutathione were also significantly decreased in CVI. In contrast, monocytes from CVI patients exhibited increased levels of both total and reduced glutathione compared with blood donor monocytes. CVI patients had significantly raised serum levels of tumor necrosis factor alpha (TNF alpha) and TNF alpha concentration was strongly associated with glutathione depletion in CD4+ lymphocytes. Furthermore, the lowest levels of both total and reduced glutathione were found in a subgroup of CVI patients characterized by persistent immune activation in vivo, decreased numbers of CD4+ lymphocytes in peripheral blood, and splenomegaly. Finally, supplementation of cell cultures with glutathione-monoethyl ester did significantly enhance interleukin-2 production from peripheral blood mononuclear cells in CVI patients. These glutathione abnormalities in CVI indicate increased oxidative stress, particularly in CD4+ lymphocytes, and intracellular depletion of reduced glutathione of the demonstrated magnitude may have profound implications for CD4+ lymphocyte function and the immunodeficiency in CVI.  相似文献   
728.
We have identified and molecularly characterized a novel deletion in the beta-globin gene cluster that is associated with elevated fetal hemoglobin in the adult. The propositus is a homozygote from the Yunnan province of China. The deletion spans about 90 kb of DNA and removes the A gamma, delta, and beta-globin genes. The 5' breakpoint of the deletion is located about 0.13 kb upstream from the A gamma-globin gene, whereas the 3' breakpoint is located about 66 kb downstream from the beta-globin gene, about 13 kb upstream from the breakpoint of the Chinese (A gamma delta beta)zero-thalassemia. Heterozygotes for this Yunnanese form of (A gamma delta beta)zero-thalassemia express between 9% and 17% of fetal hemoglobin, whereas the homozygote present with a mild anemia (Hb = 10.7 g/dl). Comparison of the sites of 3' breakpoints of the Yunnanese and the Chinese (A gamma delta beta)zero-thalassemia mutants is compatible with the hypothesis that an enhancer element is located between the 3' breakpoints of these two mutants. Juxta-position to the G gamma gene of this element may be responsible for the efficient gamma-gene expression in the Yunnanese mutant.  相似文献   
729.
Evans  SS; Wang  WC; Gregorio  CC; Han  T; Repasky  EA 《Blood》1993,81(3):759-766
Interferon-alpha (IFN-alpha) regulates the growth, differentiation, and recirculation of normal and malignant B lymphocytes. In this report we examine the effects of IFN-alpha on the distribution of the cytoskeletal protein spectrin in peripheral blood B lymphocytes from normal donors and patients diagnosed with chronic lymphocytic leukemia (CLL) and hairy cell leukemia (HCL). Exposure of normal and leukemic B cells to IFN-alpha in vitro was shown by immunofluorescence microscopy to cause a dose-dependent increase in the percentage of cells containing discrete focal accumulations of spectrin, ie, a single large aggregate or cap-like structure near the plasma membrane. Although the magnitude of this effect was variable among individual patient samples, in some experiments IFN-alpha induced a fourfold increase in the percentage of leukemic B cells exhibiting focal accumulations of spectrin. Spectrin reorganization induced by IFN-alpha was abrogated by the protein synthesis inhibitor cycloheximide. In addition, IFN-alpha increased the total cellular content of spectrin in B-CLL cells by approximately twofold to fourfold. Finally, a role for protein kinase C in mediating the effects of IFN-alpha on spectrin's organization is implicated by studies in which calphostin C inhibited the IFN-induced focal accumulation of spectrin. Taken together, these studies suggest that the immunomodulatory activities of IFN-alpha in normal and malignant B cells involve a change in the organization of the spectrin- based cytoskeleton.  相似文献   
730.
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