排序方式: 共有36条查询结果,搜索用时 15 毫秒
1.
Michelle Berresheim Jodi Wilkie Kara A. Nerenberg Quazi Ibrahim Tammy J. Bungard 《Thrombosis research》2014
Introduction
Pregnancy is a thrombogenic state, increasing the risk for venous thromboembolism (VTE), and the risk of valve thrombosis amongst women with mechanical heart valves (MHV). While low molecular weight heparins (LMWH) are generally dosed based on weight (i.e., enoxaparin 1 mg/kg every 12 hours), data in pregnant women have shown that weight-based dosing does not consistently achieve target anti-Xa levels. In women with MHV, our practice includes titrating LMWH doses to target both trough and peak anti-Xa levels, while for those with VTE peak anti-Xa levels guide dosing.Materials/Methods
This retrospective case series included pregnant women requiring LMWH treatment doses with at least 3 peak (+/− trough) anti-Xa levels. Our primary objective was to describe the actual LMWH dose required to achieve targeted anti-Xa levels relative to weight-based dosing in patients with MHV. Secondarily, we compared the same for VTE patients; compared actual dosing between those with MHV and VTE; and examined maternal and fetal outcomes.Results/Conclusion
Women with MHV (N = 4) required greater than weight-based dosing of enoxaparin (1.35 mg/kg Q12H) to achieve targeted anti-Xa levels. Importantly, achieving target peak anti-Xa levels did not always ensure maintenance of minimum trough levels. VTE patients (N = 12) did not require more enoxaparin (0.96 mg/kg Q12H) than weight based dosing. MHV patients received more enoxaparin compared to VTE patients (P < 0.001). No bleeding or clotting complications were associated with LMWH administration. In pregnant women with MHV at high risk of thromboembolism, LMWH dosing guided by trough and peak anti-Xa levels should be considered. 相似文献2.
Christian Monsé Horst Christoph Broding Kirsten Sucker Hans Berresheim Birger Jettkant Frank Hoffmeyer Rolf Merget Thomas Brüning Jürgen Bünger 《International archives of occupational and environmental health》2014,87(4):413-421
Purpose
In a potash mine in the center of Germany, stationary measurements 40 cm above ground level have revealed occasional increases in the carbon dioxide (CO2) levels that exceed the 0.5 vol.% German occupational exposure limit (OEL). This study, therefore, aimed to examine the individual exposures of potash miners to CO2 at their underground workplaces.Methods
119 miners were equipped with personal CO2 detectors to log the individual CO2 exposures during underground work. We decided to use electrochemical monitors due to their compactness and minimal mass. Furthermore, generated CO2 measurements with precipitated overshooting and false positive CO2 values were studied using diverse CO2 test gases and different fumigation times.Results
The personal detectors showed short-term CO2 peak exposures at very high concentrations in a limited number of workers. Twenty-two threshold limit value violations were observed according to the present OEL, and the personal CO2 monitoring allowed categorization into three exposure groups, low (n = 83), moderate (n = 26) and high burdens (n = 10) of CO2.Conclusions
The electrochemical sensors used have numerous properties that can potentially influence the assessment of exposures. The current findings suggest that assessing similar exposure scenarios, with respect to elevated and strongly fluctuating CO2 concentrations, the behavior of electrochemical sensors should be taken into consideration. 相似文献3.
Monsé C Sucker K van Thriel C Broding HC Jettkant B Berresheim H Wiethege T Käfferlein H Merget R Bünger J Brüning T 《Inhalation toxicology》2012,24(2):99-108
Exposures to air contaminants, such as chemical vapors and particulate matter, pose important health hazards at workplaces. Short-term experimental exposures to chemical vapors and particles in humans are a promising attempt to investigate acute effects of such hazards. However, a significant challenge in this field is the determination of effects of co-exposures to more than one chemical or mixtures of chemical vapors and/or particles. To overcome such a challenge, studies have to be conducted under standardized exposure characterization and real time measurements, if possible. A new exposure laboratory (ExpoLab) was installed at IPA, combining sophisticated engineering designs with new analytical techniques, to fulfill these requirements. Low-dose as well as high-dose exposure scenarios are achieved by means of a calibration-gas-generator. Exposure monitoring can be carried out with a high performance real time mass spectrometer and other suitable analyzers (e.g. gas chromatograph). Numerous automated security facilities guarantee the physical integrity of the volunteers, and the waste atmosphere is removed using either charcoal filtration or catalytic post-combustion. Measurements of sulfur hexafluoride, carbon dioxide, aniline and carbon black are presented to demonstrate the performance of the exposure unit with respect to the temporal and spatial stability of generated atmospheres. The variations of generated contents in the atmospheres at steady state are slightly higher than the measurement precision of the analyzers (the typical standard deviation of generated atmospheres is < 2%). The technical components of ExpoLab and its monitoring systems ensure high quality standards in validity and reliability of generating and measuring exposure atmospheres. 相似文献
4.
van Thriel C Schäper M Kiesswetter E Kleinbeck S Juran S Blaszkewicz M Fricke HH Altmann L Berresheim H Brüning T 《International archives of occupational and environmental health》2006,79(4):308-321
Objectives: To ensure safety and health the avoidance of adverse chemosensory effects is essential at workplaces where volatile chemicals
are used. The present study describes psychophysical approaches that provide information for the evaluation of such effects.
Methods: By means of a modified staircase procedure the odor (OT) and irritation thresholds (IT) of 15 irritants were determined.
These basic chemosensory properties, confining the chemosensory effect range, were investigated in a random sample of 144
persons stratified for gender and age. Those irritants exhibiting high chemosensory potency were selected for the second psychophysical
part of the study. Forty-eight persons, again stratified for gender and age, rated the intensity of 13 trigeminal and olfactory
perceptions elicited by nine ascending concentrations of the irritants, ranging from the odor to the irritation threshold
of the respective substances. Results: Across the investigated chemicals the transition from concentrations eliciting pure olfactory stimulation (OT) to trigeminal
stimulation (IT) differed markedly. The carboxylic acids yielded narrow ranges from odor to irritation thresholds, while for
the amines (cyclohexylamine, dimethylamine, and trimethylamine) and the esters (ethyl formate and ethyl acetate) these ranges
were somewhat wider. The two chemosensory thresholds of ethyl acrylate and ammonia were farthest from each other. Gender and
age had only weak impact on the chemosensory thresholds. At present, the results of the intensity ratings could be given for
six substances. Among them, the rated pungency for cyclohexylamine, formic acid, and ethyl acetate increased strongest across
the nine applied concentrations. Conclusions: By means of these psychophysical approaches a diverse class of chemicals can be described and compared with respect to their
chemosensory potency. This information can be used twofold (a) for the evaluation of existing studies reporting sensory irritations
and (b) for the design of experimental exposure studies. 相似文献
5.
Papo D Eberlein-König B Berresheim HW Huss-Marp J Grimm V Ring J Behrendt H Winneke G 《Journal of psychosomatic research》2006,60(2):199-209
OBJECTIVE: We addressed the question if patients with multiple chemical sensitivity (MCS) differ from participants with self-reported odor sensitivity without MCS and asymptomatic controls in terms of chemosensory, cognitive, and clinical psychological endpoints. METHODS: In a clinical study 23 MCS patients, 21 participants with self-reported odor sensitivity, and 23 controls were investigated using electrophysiological and psychophysical olfactometric tests [chemosensory-event-related potentials (CSERP), olfactory thresholds, odor identification, trigeminal sensitivity]. The participants filled in a mood list, a list of complaints (BL), a Symptom Check List, a State-Trait Anxiety Inventory (STAI), and an MCS questionnaire. RESULTS: The olfactometric investigations revealed no significant differences between the groups. The MCS group reached significantly higher scores on negative mood states following odorant exposure, on health complaints, global indices, and the somatization subscale of the Symptom Check List, trait and state anxiety and symptoms, and triggering matters of the MCS questionnaire. CONCLUSIONS: Our findings reveal that neither olfactory functions, nor chemosensory or cognitive olfactory information processing are impaired in MCS patients. They rather support findings of altered psychological profile and moderate psychopathology. 相似文献
6.
Hoffmeyer F Raulf-Heimsoth M Lehnert M Kendzia B Bernard S Berresheim H Düser M Henry J Weiss T Koch HM Pesch B Brüning T;Weldox Group 《Journal of toxicology and environmental health. Part A》2012,75(8-10):525-532
Total mass and composition of welding fumes are predominantly dependent on the welding technique and welding wire applied. The objective of this study was to investigate the impact of welding techniques on biological effect markers in exhaled breath condensate (EBC) of 58 healthy welders. The welding techniques applied were gas metal arc welding with solid wire (GMAW) (n=29) or flux cored wire (FCAW) (n=29). Welding fume particles were collected with personal samplers in the breathing zone inside the helmets. Levels of leukotriene B(4) (LTB(4)), prostaglandin E(2) (PGE(2)), and 8-isoprostane (8-iso-PGF(2α)) were measured with immunoassay kits and the EBC pH was measured after deaeration. Significantly higher 8-iso-PGF(2α) concentrations and a less acid pH were detected in EBC of welders using the FCAW than in EBC of welders using the GMAW technique. The lowest LTB(4) concentrations were measured in nonsmoking welders applying a solid wire. No significant influences were found in EBC concentrations of PGE(2) based upon smoking status or type of welding technique. This study suggests an enhanced irritative effect in the lower airways of mild steel welders due to the application of FCAW compared to GMAW, most likely associated with a higher emission of welding fumes. 相似文献
7.
J Krugmann S Dirnhofer A Gschwendtner U Berresheim R Greil K Krugmann F Fend 《Pathology, research and practice》2001,197(6):385-393
We hereby present a retrospective clinicopathological and immunohistochemical study of surgically resected primary gastrointestinal (GI) lymphoma with an analysis of parameters of potential prognostic relevance. From a larger series of 144 cases of primary GI lymphomas, we chose 61 cases with sufficient clinical follow-up (mean 60, range 1-219 months), classified either as extranodal marginal zone B-cell lymphoma of MALT type (MALT lymphoma) or diffuse large B-cell lymphoma (DLBCL), after having excluded other subtypes. In addition to conventional clinical and morphological parameters, the expression levels of Ki-67 (MIB-1), bcl-2 and p53 were evaluated for prognostic significance. Twenty-one (34.4%) cases were classified as pure low grade marginal zone B-cell lymphoma of MALT type, 12 (19.7%) cases as low grade MALT lymphoma with a high grade component (mixed type), and 28 (45.9%) cases as primary extranodal DLBCL. Most of the lymphomas (53/61; 86.9%) were localized in the stomach, 3 (4.9%) in the small bowel, 3 (4.9%) multifocal in both stomach and small intestine and 2 (3.3%) in the large bowel. MIB-1 expression in more than 30% of tumor cells was detected in 42 (68.6%), bcl-2 expression in 20 (32.8%) and p53 accumulation in more than 10% of neoplastic cells in 16 (26.2%) lymphomas. Both high Ki-67 expression and p53 accumulation were more prevalent in the DLBCL. 30 (49%) patients showed lymph node involvement at surgery, 14 (23%) patients suffered tumor recurrence, and 24 (38.5%) died during the follow-up period. Tumor recurrence occurred primarily in patients who had presented lymph node involvement (9/14, 64.3%). The 5-year survival rate was 66.1% for all patients. Important prognostic factors for overall survival were tumor stage (p < .004) and p53 accumulation (p < .05) in univariate analysis, and tumor stage in multivariate analysis (p < .001). Although p53 accumulation did not reach statistical significance in our small study group, it may be both important in the transformation of low grade MALT lymphoma and an indicator for aggressive behavior in high grade tumors. 相似文献
8.
Dominik Soll Finja Beer Leonard Spranger Linna Li Joachim Spranger Knut Mai 《Obesity facts》2022,15(1):90
IntroductionNeuropilin 1 (NRP-1) is a novel co-receptor promoting SARS-CoV-2 infectivity. Animal data indicate a role in trans-endothelial lipid transport and storage. As human data are sparse, we aimed to assess the role of NRP-1 in 2 metabolic active tissues in human obesity and in the context of weight loss-induced short- and long-term metabolic changes.MethodsAfter a standardized 12-week weight reduction program, 143 subjects (age >18; body mass index ≥27 kg/m<sup>2</sup>, 78% female) were randomized to a 12-month lifestyle intervention or a control group using a stratified randomization scheme. This was followed by 6-month follow-up without any intervention. Phenotyping was performed before and after weight loss, after 12-month intervention and after subsequent 6 months of follow-up. Tissue-specific insulin sensitivity was estimated by HOMA-IR (whole body and mostly driven by liver), insulin sensitivity index (ISI)Clamp (predominantly skeletal muscle), and free fatty acid (FFA) suppression during hyperinsulinemic-euglycemic clamp (FFASupp) (predominantly adipose tissue). NRP-1 mRNA expression was measured in subcutaneous adipose tissue (NRP-1AT) and skeletal muscle (NRP-1SM) before and after weight loss.ResultsNRP-1 was highly expressed in adipose tissue (7,893 [7,303–8,536] counts), but neither NRP-1AT nor NRP-1SM were related to estimates of obesity. Higher NRP-1AT was associated with stronger FFASupp (r = −0.343, p = 0.003) and a tendency to higher ISIClamp (r = 0.202, p = 0.085). Weight loss induced a decline of NRP-1AT but not NRP-1SM. This was more pronounced in subjects with stronger reduction of adipose ACE-2 mRNA expression (r = 0.250; p = 0.032) but was not associated with short- and long-term improvement of FFASupp and ISIClamp.ConclusionNRP-1AT is related to adipose insulin sensitivity in obesity. Weight loss-induced decline of NRP-1AT seems not to be involved in metabolic short- and long-term improvements after weight loss. However, weight loss-induced reduction of both NRP-1AT and ACE-2AT indicates a lower susceptibility of adipose tissue for SARS-CoV-2 after body weight reduction. 相似文献
9.