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1.
To assess a potential common pattern of genetic alterations in chemotherapy-resistant tumors we analyzed four tumors from breast cancer patients (patients 1-4) after neoadjuvant chemotherapy, by comparative genome hybridization (CGH) and conventional chromosome banding analysis. All patients showed structural aberrations involving chromosomes 1, 5, 11, 16, and 17. In CGH analysis, the patients showed typical imbalances for ductal breast cancer: gains of 1q (3 patients), 5q (2 patients), 8q (3 patients), and X (4 patients) and losses of 1p33 approximately p36 (3 patients), 16q (3 patients), 17p (3 patients), 19 (4 patients), and 22q (4 patients). Other recurrent imbalances of atypical pattern for ductal breast cancer were gain of 4q21 approximately q32 (2 patients), 20q21 approximately q22 (2 patients), and 21 (2 patients) and loss of 20p (3 patients). Three patients showed involvement of several regions bearing genes of drug resistance (MDR1 [HUGO symbol: ABCB1], BCRP [HUGO symbol: ABCG2], MRP1 [HUGO symbol: ABCC1], RFC1); the fourth patient displayed an amplification in the region of MYC (alias c-myc), thus providing--at the level of the light microscope--an explanatory background for the ability of their tumors to survive anthracycline-, taxane- and cyclophosphamide-based chemotherapy. Conventional cytogenetic analysis and CGH displayed highly coincidental findings in the tumors of four patients after neoadjuvant chemotherapy for breast cancer.  相似文献   
2.
We investigated the phagocytosis of Haemophilus ducreyi both in vitro and in vivo. Human granulocyte and monocyte phagocytosis of opsonized and nonopsonized, fluorescence-labeled H. ducreyi was assessed by flow cytometry. Both Escherichia coli and noncapsulated H. influenzae were included as controls. The maximal percentage of granulocytes taken up by H. ducreyi was 35% after 90 min. In contrast, 95% of H. influenzae bacteria were phagocytosed by granulocytes after 30 min. These results indicated that H. ducreyi phagocytosis was slow and inefficient. Bacterial opsonization by using specific antibodies increased the percentage of granulocytes phagocytosing H. ducreyi from 24 to 49%. The nonphagocytosed bacteria were completely resistant to phagocytosis even when reexposed to granulocytes, indicating that the H. ducreyi culture comprised a mixture of phenotypes. The intracellular survival of H. ducreyi in granulocytes, in monocytes/macrophages, and in a monocyte cell line (THP-1) was quantified after application of gentamicin treatment to kill extracellular bacteria. H. ducreyi survival within phagocytes was poor; approximately 11 and <0.1% of the added bacteria survived intracellularly after 2 and 20 h of incubation, respectively, while no intracellular H. influenzae bacteria were recovered after 2 h of incubation with phagocytes. The role of phagocytes in the development of skin lesions due to H. ducreyi was also studied in vivo. Mice that were depleted of granulocytes and/or monocytes and SCID mice, which lacked T and B cells, were injected intradermally with approximately 106 CFU of H. ducreyi. Within 4 days of inoculation, the granulocyte-depleted mice developed lesions that persisted throughout the experimental period. This result reinforces the importance of granulocytes in the early innate defense against H. ducreyi infection. In conclusion, H. ducreyi is insufficiently phagocytosed to achieve complete eradication of the bacteria. Indeed, H. ducreyi has the ability to survive intracellularly for short periods within phagocytic cells in vitro. Since granulocytes play a major role in the innate defense against H. ducreyi infection in vivo, bacterial resistance to phagocytosis probably plays a crucial role in the pathogenesis of chancroid.  相似文献   
3.
Summary Biochemical investigation of the fluid surrounding the sporocysts in the oocysts (oocyst fluid) showed the presence of the common amino acids, -isoaminobutyric acid, glycerol, an unidentified carbohydrate and proteins.Incubation experiments with D-glucose-14C (U) revealed the presence of enzymes able to convert glucose into lactic acid and other acids. Inside the sporocysts the common amino acids, glycerol and the unidentified carbohydrate were also present, but -isoaminobutyric acid did not occur. The carbohydrate binding protein carboglutelin, carbohydrate phosphate and small amounts of glucose and fructose were mainly found inside the sporocysts.Incubation experiments of oocyst fluid mixed with sporocysts with D-glucose-C14 (U) demonstrated an interchange between the fluid and the sporocysts. In the oocyst fluid lactic acid was formed, but inside the sporocysts the conversion appeared to stop mainly with formation of carbohydrate phosphate.Incubation experiments of intestinal pieces both from immunized and not-immunized birds with oocyst fluid, sporocysts and labelled glucose showed that a stronger reaction took place in immunized birds than in not-immunized ones.Similar experiments were performed with not-immunized birds at different days after a primary infection. The reaction of the intestinal wall, which seemed quite normal again since day 19 after infection, was comparable with that observed in immunized birds.Finally the hypothesis is given, that in the first part of the intestine of immunized birds compounds are present originating from the first infection. These compounds might enhance the reaction between the oocyst fluid and the present feed to such an extent that the pH decreases and much epithelial cells are pushed off possibly together with the sporocysts. Then leakage of serum proteins might occur.  相似文献   
4.
5.
We present a systematic review of the literature on the prevalence, nature, severity, course, and causes of cognitive deficits in patients with occlusive disease of the carotid artery prior to surgery (if surgery was under discussion). Searches were carried out on Medline and Psychlit from 1980 to 1999 using neurovascular and psychological index terms, and papers and books were checked for further references. Studies describing neuropsychological assessment of groups of patients with carotid obstruction were included. Eighteen studies were found. We extracted from the papers data on study design, demographic characteristics of patients, clinical diagnosis, carotid obstruction, cerebral imaging, time interval between ischemic episode and neuropsychological assessment, neuropsychological asessment procedures, integration and interpretation of test performances, and conclusions of authors. Fourteen studies concluded that there are cognitive deficits both in patients with symptomatic and in those with asymptomatic carotid obstruction; four studies denied cognitive impairment. There were no differences in patient characteristics, study design, or neuropsychological assessment procedures between the 14 studies that found deficits and the 4 that did not. There are indications for a mild, diffuse, detrimental effect of carotid occlusive disease on cognitive functioning. However, methodological problems prevent a definitive conclusion. Further research is needed to confirm these findings and to ascertain the neurovascular risk factors for and the natural course of cognitive impairment in patients with carotid occlusive disease. Received: 12 July 1999/Received in revised form: 10 November 1999/Accepted: 26 January 2000  相似文献   
6.
We report a severe acute respiratory syndrome coronavirus 2 superspreading event in the Netherlands after distancing rules were lifted in nightclubs, despite requiring a negative test or vaccination. This occurrence illustrates the potential for rapid dissemination of variants in largely unvaccinated populations under such conditions. We detected subsequent community transmission of this strain.  相似文献   
7.
Background Skeletal trauma and immobilization are well-known risk factors for deep vein thrombosis (DVT) and pulmonary embolism (PE). While prophylaxis against thromboembolic complications has become routine after major orthopedic surgery, whether or not prophylaxis after minor surgery and lower limb immobilization is necessary is still under debate.

Methods In a double-blind, placebo-controlled study, 272 consecutive patients were randomized to receive either thromboprophylaxis with Dalteparin (n = 136) or placebo (n = 136) for 5 weeks after ankle fracture surgery. All patients received 1 week of initial treatment with Dalteparin before randomization. A unilateral phlebography was performed when the cast was removed.

Results The overall incidence of DVT was 21% (95% CI: 13-29%) in the Dalteparin group and 28% (CI: 19- 37%) in the placebo group (risk ratio = 0.8, CI: 0.6-1.1; p = 0.3). The incidence of proximal DVTs was 4% and 3%, respectively. No major bleeding occurred.

Interpretation We found no significant difference in the incidence of DVT between the 2 treatment groups and our results do not support prolonged thromboprophylaxis. The overall incidence of DVT was high, reflecting the potential risk of PE and post-thrombotic syndrome after ankle fracture surgery. Most of the DVTs were asymptomatic, however, and were located in distal veins.  相似文献   
8.
Transplant type for end‐stage pulmonary vascular disease remains debatable. We compared recipient outcome after heart‐lung (HLT) versus double‐lung (DLT) transplantation. Single‐center analysis (38 HLT–30 DLT; 1991–2014) for different causes of precapillary pulmonary hypertension (PH): idiopathic (22); heritable (two); drug‐induced (nine); hepato‐portal (one); connective tissue disease (four); congenital heart disease (CHD) (24); chronic thromboembolic PH (six). HLT decreased from 91.7% [1991–1995] to 21.4% [2010–2014]. Re‐intervention for bleeding was higher after HLT; (P = 0.06) while primary graft dysfunction grades 2 and 3 occurred more after DLT; (P < 0.0001). Graft survival at 90 days, 1, 5, 10, and 15 years was 93%, 83%, 70%, 47%, and 35% for DLT vs. 82%, 74%, 61%, 48%, and 30% for HLT, respectively (log‐rank = 0.89). Graft survival improved over time: 100%, 93%, 87%, 72%, and 72% in [2010–2014] vs. 75%, 58%, 42%, 33%, and 33% in [1991–1995], respectively; P = 0.03. No difference in chronic lung allograft dysfunction (CLAD)‐free survival was observed: 80% & 28% for DLT vs. 75% & 28% for HLT after 5 and 10 years, respectively; = 0.49. Primary graft dysfunction in PH patients was lower after HLT compared to DLT. Nonetheless, overall graft and CLAD‐free survival were comparable and improved over time with growing experience. DLT remains our preferred procedure for all forms of precapillary PH, except in patients with complex CHD.  相似文献   
9.
To achieve sample sizes necessary for effectively conducting genome‐wide association studies (GWASs), researchers often combine data from samples possessing multiple potential sources of heterogeneity. This is particularly relevant for psychiatric disorders, where symptom self‐report, differing assessment instruments, and diagnostic comorbidity complicates the phenotypes and contribute to difficulties with detecting and replicating genetic association signals. We investigated sources of heterogeneity of anxiety disorders (ADs) across five large cohorts used in a GWAS meta‐analysis project using a dimensional structural modeling approach including confirmatory factor analyses (CFAs) and measurement invariance (MI) testing. CFA indicated a single‐factor model provided the best fit in each sample with the same pattern of factor loadings. MI testing indicated degrees of failure of metric and scalar invariance which depended on the inclusion of the effects of sex and age in the model. This is the first study to examine the phenotypic structure of psychiatric disorder phenotypes simultaneously across multiple, large cohorts used for GWAS. The analyses provide evidence for higher order invariance but possible break‐down at more detailed levels that can be subtly influenced by included covariates, suggesting caution when combining such data. These methods have significance for large‐scale collaborative studies that draw on multiple, potentially heterogeneous datasets. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
10.
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