327 research outputs found

    Femoral fractures : indications an[d] biomechanics of external fixation

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    Internal fixation can be carried out in various ways. For femoral shaft fractures, an (interlocking) nail is becoming increasingly popular, instead of open realignment of the fracture. External fixation, which has become a generally accepted method of treating fractures of the lower leg, has been used infrequently on the upper leg. During the last 100 years, several different types of external fixation have been tested on femoral shaft fractures on a limited scale in various parts of the world. It is clear that external fixation offers good prospects for treating serious, (possibly) comminuted, compound femoral shaft fractures (often in combination with blood vessel and nerve injuries). Only a few authors elect to use external fixation on all femoral shaft fractures, including those in children. Various views exist on the indications, treatment schemes and adjunct therapy. The search for similarities and background information was one of the first objectives of this study. The biomechanical aspects play a central part in this. An overview of the literature on the treatment of femoral fractures is given and the relationship between the anatomy of the upper leg and external fixation is investigated. Experimental models have been used to answer the question of what forces act upon the femur and how they are neutralized by external fixation. The histological aspects of fracture healing during stable and unstable (external) fixation are discussed briefly together with their clinical consequences. A large proportion of this thesis is taken up by biomechanical research, in which the rigidity and elastic deformation of 12 different external fixation frames (applied to the femur) were analyzed. To illustrate the clinical prospects (and the relationship with biomechanical studies) representative case histories of patients have been adde

    Training general practitioners to improve evidence-based drug treatment of patients with heart failure: a cluster randomised controlled trial

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    AIMS: To assess whether a single training session for general practitioners (GPs) improves the evidence-based drug treatment of heart failure (HF) patients, especially of those with HF with reduced ejection fraction (HFrEF). METHODS AND RESULTS: A cluster randomised controlled trial was performed for which patients with established HF were eligible. Primary care practices (PCPs) were randomised to care-as-usual or to the intervention group in which GPs received a half-day training session on HF management. Changes in HF medication, health status, hospitalisation and survival were compared between the two groups. Fifteen PCPs with 200 HF patients were randomised to the intervention group and 15 PCPs with 198 HF patients to the control group. Mean age was 76.9 (SD 10.8) years; 52.5% were female. On average, the patients had been diagnosed with HF 3.0 (SD 3.0) years previously. In total, 204 had HFrEF and 194 HF with preserved ejection fraction (HFpEF). In participants with HFrEF, the use of angiotensin-converting enzyme inhibitors/angiotensin receptor blockers decreased in 6 months in both groups [5.2%; (95% confidence interval (CI) 2.0-10.0)] and 5.6% (95% CI 2.8-13.4)], respectively [baseline-corrected odds ratio (OR) 1.07 (95% CI 0.55-2.08)], while beta-blocker use increased in both groups by 5.2% (95% CI 2.0-10.0) and 1.1% (95% CI 0.2-6.3), respectively [baseline-corrected OR 0.82 (95% CI 0.42-1.61)]. For health status, hospitalisations or survival after 12-28 months there were no significant differences between the two groups, also not when separately analysed for HFrEF and HFpEF. CONCLUSION: A half-day training session for GPs does not improve drug treatment of HF in patients with established HF

    External validation of prediction models for pneumonia in primary care patients with lower respiratory tract infection: an individual patient data meta-analysis

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    Pneumonia remains difficult to diagnose in primary care. Prediction models based on signs and symptoms (S&S) serve to minimize the diagnostic uncertainty. External validation of these models is essential before implementation into routine practice. In this study all published S&S models for prediction of pneumonia in primary care were externally validated in the individual patient data (IPD) of previously performed diagnostic studies

    Testing grain-surface chemistry in massive hot-core regions

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    A partial submillimeter line-survey was performed toward 7 high-mass young stellar objects (YSOs) aimed at detecting H2CO, CH3OH, CH2CO, CH3CHO, C2H5OH, HCOOH, HNCO and NH2CHO. In addition, other organic species such as CH3CN have been observed. The aim is to establish the chemical origin of a set of complex organic molecules thought to be produced by grain surface chemistry in high mass YSOs. Rotation temperatures and beam-averaged column densities are determined. Based on their rotation diagrams, molecules can be classified as either cold (100 K). This implies that complex organics are present in at least two distinct regions. Furthermore, the abundances of the hot oxygen-bearing species are correlated, as are those of HNCO and NH2CHO. This is suggestive of chemical relationships within, but not between, those two groups of molecules. The most likely explanation for the observed correlations of the various hot molecules is that they are ``first generation'' species that originate from solid-state chemistry. This includes H2CO, CH3OH, C2H5OH, HCOOCH3, CH3OCH3, HNCO, NH2CHO, and possibly CH3CN, and C2H5CN. The correlations between sources implies very similar conditions during their formation or very similar doses of energetic processing. Cold species such as CH2CO, CH3CHO, and HCOOH, some of which are seen as ices along the same lines of sight, are probably formed in the solid state as well, but appear to be destroyed at higher temperatures. A low level of non-thermal desorption by cosmic rays can explain their low rotation temperatures and relatively low abundances in the gas phase compared to the solid state. The CH3CCH abundances can be fully explained by low temperature gas phase chemistry. No cold N-containing molecules are found.Comment: 20 pages, 8 figures, accepted by Astronomy and Astrophysic

    Incidence of Antibiotic Exposure for Suspected and Proven Neonatal Early-Onset Sepsis between 2019 and 2021:A Retrospective, Multicentre Study

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    Management of suspected early-onset sepsis (EOS) is undergoing continuous evolution aiming to limit antibiotic overtreatment, yet current data on the level of overtreatment are only available for a select number of countries. This study aimed to determine antibiotic initiation and continuation rates for suspected EOS, along with the incidence of culture-proven EOS in The Netherlands. In this retrospective study from 2019 to 2021, data were collected from 15 Dutch hospitals, comprising 13 regional hospitals equipped with Level I-II facilities and 2 academic hospitals equipped with Level IV facilities. Data included birth rates, number of neonates started on antibiotics for suspected EOS, number of neonates that continued treatment beyond 48 h and number of neonates with culture-proven EOS. Additionally, blood culture results were documented. Data were analysed both collectively and separately for regional and academic hospitals. A total of 103,492 live-born neonates were included. In 4755 neonates (4.6%, 95% CI 4.5–4.7), antibiotic therapy was started for suspected EOS, and in 2399 neonates (2.3%, 95% CI 2.2–2.4), antibiotic treatment was continued beyond 48 h. Incidence of culture-proven EOS was 1.1 cases per 1000 live births (0.11%, 95% CI 0.09–0.14). Overall, for each culture-proven EOS case, 40.6 neonates were started on antibiotics and in 21.7 neonates therapy was continued. Large variations in treatment rates were observed across all hospitals, with the number of neonates initiated and continued on antibiotics per culture-proven EOS case varying from 4 to 90 and from 4 to 56, respectively. The high number of antibiotic prescriptions compared to the EOS incidence and wide variety in clinical practice among hospitals in The Netherlands underscore both the need and potential for a novel approach to the management of neonates with suspected EOS.</p

    Strategies, methods and tools for managing nanorisks in construction

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    This paper presents a general overview of the work carried out by European project SCAFFOLD (GA 280535) during its 30 months of life, with special emphasis on risk management component. The research conducted by SCAFFOLD is focused on the European construction sector and considers 5 types of nanomaterials (TiO2, SiO2, carbon nanofibres, cellulose nanofibers and nanoclays), 6 construction applications (Depollutant mortars, selfcompacting concretes, coatings, self-cleaning coatings, fire resistant panels and insulation materials) and 26 exposure scenarios, including lab, pilot and industrial scales. The document focuses on the structure, content and operation modes of the Risk Management Toolkit developed by the project to facilitate the implementation of "nano-management" in construction companies. The tool deploys and integrated approach OHSAS 18001 - ISO 31000 and is currently being validated on 5 industrial case studies.Research carried out by project SCAFFOLD was made possible thanks to funding from the European Commission, through the Seventh Framework Programme (GA 280535

    Ductal carcinoma in situ and sentinel lymph node metastasis in breast cancer

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    <p>Abstract</p> <p>Background</p> <p>The impact of sentinel lymph node biopsy on breast cancer mimicking ductal carcinoma in situ (DCIS) is a matter of debate.</p> <p>Methods</p> <p>We studied the rate of occurrence of sentinel lymph node metastasis in 255 breast cancer patients with pure DCIS showing no invasive components on routine pathological examination. We compared this to the rate of occurrence in 177 patients with predominant intraductal-component (IDC) breast cancers containing invasive foci equal to or less than 0.5 cm in size.</p> <p>Results</p> <p>Most of the clinical and pathological baseline characteristics were the same between the two groups. However, peritumoral lymphatic permeation occurred less often in the pure DCIS group than in the IDC-predominant invasive-lesion group (1.2% vs. 6.8%, p = 0.002). One patient (0.39%) with pure DCIS had two sentinel lymph nodes positive for metastasis. This rate was significantly lower than that in patients with IDC-predominant invasive lesions (6.2%; p < 0.001).</p> <p>Conclusions</p> <p>Because the rate of sentinel lymph node metastasis in pure DCIS is very low, sentinel lymph node biopsy can safely be omitted.</p

    Differential responses of osteoblasts and macrophages upon Staphylococcus aureus infection

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    Background Staphylococcus aureus (S. aureus) is one of the primary causes of bone infections which are often chronic and difficult to eradicate. Bacteria like S. aureus may survive upon internalization in cells and may be responsible for chronic and recurrent infections. In this study, we compared the responses of a phagocytic cell (i.e. macrophage) to a non-phagocytic cell (i.e. osteoblast) upon S. aureus internalization. Results We found that upon internalization, S. aureus could survive for up to 5 and 7 days within macrophages and osteoblasts, respectively. Significantly more S. aureus was internalized in macrophages compared to osteoblasts and a significantly higher (100 fold) level of live intracellular S. aureus was detected in macrophages compared to osteoblasts. However, the percentage of S. aureus survival after infection was significantly lower in macrophages compared to osteoblasts at post-infection days 1–6. Interestingly, macrophages had relatively lower viability in shorter infection time periods (i.e. 0.5-4 h; significant at 2 h) but higher viability in longer infection time periods (i.e. 6–8 h; significant at 8 h) compared to osteoblasts. In addition, S. aureusinfection led to significant changes in reactive oxygen species production in both macrophages and osteoblasts. Moreover, infected osteoblasts had significantly lower alkaline phosphatase activity at post-infection day 7 and infected macrophages had higher phagocytosis activity compared to non-infected cells. Conclusions S. aureus was found to internalize and survive within osteoblasts and macrophages and led to differential responses between osteoblasts and macrophages. These findings may assist in evaluation of the pathogenesis of chronic and recurrent infections which may be related to the intracellular persistence of bacteria within host cells
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