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71.
Wenjing Tao Dag Holmberg Erik Näslund Ingmar Näslund Fredrik Mattsson Jesper Lagergren Rickard Ljung 《Obesity surgery》2016,26(8):1750-1756
Background and Aim
Swedish health registries are common sources of data for studies on the effects of obesity surgery, and there is a need to assess the quality of data in these registries. The aim of this study was to validate the registration of obesity surgery in the National Patient Registry (NPR) and the Scandinavian Obesity Surgery Registry (SOReg).Method
We randomly selected 962 out of 8501 registrations of obesity surgery in 2011 from the NPR and SOReg. Registered surgical procedures in the NPR and SOReg were compared to the medical records, and concordance was analyzed by calculating positive predictive value (PPV) with 95 % confidence interval (CI).Results
We received 938 (98 %) medical records for manual review. The overall PPV for obesity surgery was high in the NPR (PPV 97.0; 95 % CI 95.6–98.4) and even higher in SOReg (PPV 99.7; 95 % CI 99.3–100). Accuracy was higher for gastric bypass surgery than for other types of obesity surgery. Registrations that were misclassified as obesity surgery (n?=?44) included reoperations due to complications or reconstruction to normal anatomy after previous obesity surgery (n?=?11) and endoscopic procedures (n?=?10).Conclusion
Obesity surgery registrations in the NPR and SOReg have high accuracy and are reliable sources of data to identify patients having undergone obesity surgery. When it is of importance to distinguish between specific surgical procedures, non-gastric bypass surgeries in the NPR should ideally be supplemented with data from other sources.72.
Månsson LE Kjäll P Pellett S Nagy G Welch RA Bäckhed F Frisan T Richter-Dahlfors A 《Infection and immunity》2007,75(2):997-1004
Bacterial pathogens produce a variety of exotoxins, which often become associated with the bacterial outer membrane component lipopolysaccharide (LPS) during their secretion. LPS is a potent proinflammatory mediator; however, it is not known whether LPS contributes to cell signaling induced by those microbial components to which it is attached. This is partly due to the common view that LPS present in bacterial component preparations is an experimental artifact. The Escherichia coli exotoxin hemolysin (Hly) is a known inducer of proinflammatory signaling in epithelial cells, and the signal transduction pathway involves fluctuation of the intracellular-Ca(2+) concentration. Since LPS is known to interact with Hly, we investigated whether it is required as a cofactor for the activity of Hly. We found that the LPS/Hly complex exploits the CD14/LPS-binding protein recognition system to bring Hly to the cell membrane, where intracellular-Ca(2+) signaling is initiated via specific activation of the small GTPase RhoA. Hly-induced Ca(2+) signaling was found to occur independently of the LPS receptor TLR4, suggesting that the role of LPS/CD14 is to deliver Hly to the cell membrane. In contrast, the cytolytic effect triggered by exposure of cells to high Hly concentrations occurs independently of LPS/CD14. Collectively, our data reveal a novel molecular mechanism for toxin delivery in bacterial pathogenesis, where LPS-associated microbial compounds are targeted to the host cell membrane as a consequence of their association with LPS. 相似文献
73.
Soller MJ Kullendorff CM Békássy AN Alumets J Mertens F 《Cancer Genetics and Cytogenetics》2007,173(1):75-80
Adenocarcinomas of the kidney are rare childhood tumors. Only 30 cases with chromosomal abnormalities have been reported, and neither their karyotypic characteristics nor the molecular mechanisms behind their pathogenesis are clear, except for a special group of papillary tumors characterized by X-chromosome abnormalities. We have cytogenetically analyzed short-term cultured cells from two pediatric renal carcinomas, one papillary, and one chromophobe renal cell carcinoma, revealing the following karyotypes: 58-60,XX,-X,-1,+7,-8,-9,-11,-14,-15,+17,-18,-19,-21,-22 and 36,X,-X,-1,-2,-5,-6,-9,-10,-13,-17,-21/37,idem,+r/36,idem,-14,+1-2r, respectively. The findings indicate that subsets of pediatric renal cell carcinoma show karyotypes that are similar to their adult counterparts. 相似文献
74.
Hallor KH Heidenblad M Brosjö O Mandahl N Mertens F 《Cancer Genetics and Cytogenetics》2007,172(1):80-83
Fibrosarcoma of bone is a rare malignant tumor accounting for less than 5% of all primary malignant bone neoplasms. There is very limited knowledge regarding the molecular genetics of this tumor, and there are no cytogenetic data available. In the present study, a fibrosarcoma deriving from the left iliac bone of a 10-year-old girl was characterized using cytogenetics, fluorescence in situ hybridization (FISH), and whole genome tiling resolution array comparative genomic hybridization (CGH). Cytogenetic and FISH analyses revealed a ring chromosome 6 as the sole acquired aberration, a finding corroborated by array CGH. The ring formation, however, did not result in any gain of genetic material. Nor did the breakpoints in 6p25 and 6q14 seem to affect any known gene loci in such a way that the ring formation could have resulted in the creation of a fusion gene or in the exchange of regulatory sequences. Thus, a reasonable interpretation of the pathogenetic significance of the ring formation would be that it resulted in the loss of one or more putative tumor suppressor gene loci distal to the two breakpoints. 相似文献
75.
76.
77.
Ketamine and xylazine depress sensory-evoked parallel fiber and climbing fiber responses 总被引:1,自引:0,他引:1
The last few years have seen an increase in the variety of in vivo experiments used for studying cerebellar physiological mechanisms. A combination of ketamine and xylazine has become a particularly popular form of anesthesia. However, because nonanesthetized control conditions are lacking in these experiments, so far there has been no evaluation of the effects of these drugs on the physiological activity in the cerebellar neuronal network. In the present study, we used the mossy fiber, parallel fiber, and climbing fiber field potentials evoked in the nonanesthetized, decerebrated rat to serve as a control condition against which the effects of intravenous drug injections could be compared. All anesthetics were applied at doses required for normal maintenance of anesthesia. We found that ketamine substantially depressed the evoked N3 field potential, which is an indicator of the activity in the parallel fiber synapses (-40%), and nearly completely abolished evoked climbing fiber field potentials (-90%). Xylazine severely depressed the N3 field (-75%) and completely abolished the climbing fiber field (-100%). In a combination commonly used for general anesthesia (20:1), ketamine-xylazine injections also severely depressed the N3 field (-75%) and nearly completely abolished the climbing fiber field (-90%). We also observed that lowered body and surface temperatures (<34 degrees C) resulted in a substantial depression of the N3 field (-50%). These results urge for some caution in the interpretations of studies on cerebellar network physiology performed in animals anesthetized with these drugs. 相似文献
78.
Parents of boys with sex chromosome aneuploidies (SCA) were examined. Parents (22 mothers; 16 fathers) of 25 boys aged 2–18 years (M = 11.7, SD = 4.5) with SCA self-reported the Subjective Health Complaints Inventory (SHC), the Pittsburgh Sleep Quality Index, and the Personal Wellbeing Index. Parents reported more SHC and poorer daytime functioning than norms. Mothers reported more SHC, poorer sleep and daytime functioning, and lower health satisfaction than fathers. Parent-reported socio-emotional problems for sons (Strengths and Difficulties Questionnaire) significantly overlapped with parental sleep disturbance. Parental health should be considered in medical consultations involving families of boys with SCA. 相似文献
79.
80.
Simon J. Sonntag Bart Meyns Henrik C. Ahn Fredrik Pahlm Göran Hellers Azad Najar Ina Laura Pieper 《Artificial organs》2020,44(4):384-393
Realheart total artificial heart (TAH) is a novel, pulsatile, four-chamber total artificial heart which had been successfully tested acutely in a porcine animal model. However, the bovine model is better suited for long-term testing and thus an evaluation of how the design would fit the bovine anatomy was required. Virtual implantation is a method that enables a computer simulated implantation based on anatomical 3D-models created from computer tomography images. This method is used clinically, but not yet adopted for animal studies. Herein, we evaluated its suitability in the redesign of the outer dimensions and vessel connections of Realheart TAH to transition from the porcine to the bovine animal model. Virtual implantations in combination with bovine cadaver studies enabled a series of successful acute bovine implantations. Virtual implantations are a useful tool to replace the use of animals in early device development and refine subsequent necessary in vivo experiments. The next steps are to carry out human virtual implantations and cadaver studies to ensure the design is optimized for all stages of testing as well as the final recipient. 相似文献