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Transcapillary fluid balance consequences of missing initial lymphatics studied in a mouse model of primary lymphoedema 总被引:1,自引:0,他引:1
Tine V. Karlsen Marika J. Karkkainen Kari Alitalo Helge Wiig 《The Journal of physiology》2006,574(2):583-596
To investigate the phenotypic consequences of a deranged lymphangiogenesis in relation to tissue fluid accumulation and the possible role of inflammation in the pathogenesis of lymphoedema, we measured determinants of transcapillary fluid filtration and inflammatory mediators in the interstitial fluid in genetically engineered Chy mice, a model for primary congenital lymphoedema (Milroy's disease). Although initial lymphatics were not present in dermis in any of the areas studied (fore paw, hind paw, thigh and back skin) interstitial fluid pressure ( P if ), measured with micropipettes, and tissue fluid volumes were significantly increased only in the areas with visible swelling – the fore and hind paw, whereas interstitial colloid osmotic pressure (COPif ) was increased in all the skin areas examined. A volume load of 15% of body weight resulted in a more pronounced increase in P if as well as a four-fold increase in interstitial fluid volume in Chy relative to wild-type (wt) mice, showing the quantitative importance of lymphatics for fluid homeostasis during acute perturbations. A similar level of proinflammatory markers in interstitial fluid in early established lymphoedema (3–4 months) in Chy and wt suggests that inflammation does not have a major pathogenetic role for the development of lymphoedema, whereas a reduced level of the immunomodulatory cytokine interleukin (IL)-4 may result in a reduced immunological defence ability and thus lead to the increase in inflammatory cytokines IL-2 and IL-6 observed at a later stage (11–13 months). Our data suggest that primary lymphoedema results in a high interstitial fluid protein concentration that does not induce an interstitial inflammatory reaction per se , and furthermore shows the paramount importance of the initial lymphatics in tissue fluid homeostasis, especially during perturbations of transcapillary fluid balance. 相似文献
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In an attempt to identify a cause for the alteration in breathing pattern seen when conventional respiratory apparatus is applied to the face, we have studied the effects of causing the subject to focus attention on breathing by counting breaths in threes for 5 min. We used the respiratory inductance plethysmograph in 18 naive subjects who were unaware that their breathing was being measured. In the control periods, distraction was provided by a recorded story played through head-phones. The experiment was repeated with the rim of a facemask applied to the face. Focusing attention on breathing caused a prolongation of inspiration at a constant mean inspiratory flow, and lengthening of expiration. Tidal volume but not ventilation was increased. The facemask rim caused no significant change. It is concluded that conscious awareness of breathing could account for a major part of the effect of conventional respiratory apparatus. 相似文献
5.
Kari Hemminki Xinjun Li 《Journal of occupational and environmental medicine / American College of Occupational and Environmental Medicine》2003,45(4):456-461
Epidemiologic data on pleural mesothelioma are scarce on regional and occupational time trends, which would monitor the effects of changes in exposure to asbestos. We aim to characterize time trends, regional, socioeconomic, and occupational risk factors for pleural mesothelioma in Sweden in the years from 1961 to 1998. The Swedish Family-Cancer Database was used to identify patients with pleural mesothelioma. Age-standardized incidence rates and standardized incidence ratio (SIR) were calculated for the population in the Database. A total of 1298 male and 233 female pleural mesotheliomas were retrieved. Age-standardized incidence of the disease was highest, and the trend increased in residents of large industrial and shipbuilding cities. In the last follow-up period, the male rate exceeded the female rate about 10-fold. Among male socioeconomic groups, manual workers showed the highest and ever-increasing SIR. No female socioeconomic group was at risk. For men, plumbers and seamen had the highest risk of 4.56 and 2.83, respectively, but the risks appeared to be decreasing for plumbers, whereas no clear trend was noted for seamen, probably because of indirect expose in ships. Farmers showed an SIR of 0.28, indicating that the population at large was at four times higher risk than farmers. The SIRs of many academic/college-educated groups were two to six times higher than those of farmers, suggesting indirect exposure to asbestos in these groups. 相似文献
6.
Anu Juslin Jyrki L?tj?nen Sergey V Nesterov Kari Kalliokoski Juhani Knuuti Ulla Ruotsalainen 《Journal of nuclear cardiology》2007,14(1):82-91
BACKGROUND: The aim of this study was to develop a method to correct the heart position between two oxygen 15-labeled water cardiac positron emission tomography (PET) image sets to be able to use the equivalent regions of interest for the quantification of the perfusion values in the same myocardial segments. METHODS AND RESULTS: Independent component analysis was applied to the dynamic image sets (simulated phantom and 6 rest-pharmacologic stress and 10 rest-rest image sets of healthy female volunteers) acquired at different time points to separate the cardiac structures (ventricles and myocardium). The separated component images from independent component analysis from the 2 studies of the same individual were aligned with a normalized mutual information-based registration method. The alignment parameters were applied to position the regions of interest in the floating image sets for calculation of the myocardial blood flow values. In the rest case the mean myocardial blood flow value was 0.76 +/- 0.12 mL x g(-1) x min(-1) for the manual method and 0.79 +/- 0.10 mL x g(-1) x min(-1) for the proposed method (by use of the right ventricle component in the alignment), and in the stress case these values were 3.39 +/- 0.70 mL x g(-1) x min(-1) and 4.01 +/- 0.71 mL x g(-1) x min(-1), respectively. No statistically significant difference was found between the methods. CONCLUSION: In the tests with the phantom and patient images the alignment of cardiac structures was shown to be successful. The alignment could be done without the use of information from the myocardial compartment. 相似文献
7.
Kari Aalto Teddy Holmstr m Erkki Karaharju Jaakko Joukainen Pekka Paavolainen Par Sl tis 《Acta orthopaedica》1987,58(1):66-70
Bone repair was studied in the rabbit tibiofibular bone after a midshaft transverse osteotomy stabilized by external fixation and heavy compression. Both subendosteal and subperiosteal callus formation with concomitant contact healing were observed within 3 weeks, and were further succeeded by subendosteal resorption and increased porosis resulting in atrophy of the cortical bone. Subjected to the torsion test, the bones exhibited restoration of strength within 3 weeks, with maximal energy absorption and elasticity at 6 weeks. The failure of the osteotomy in the torsion test, with radiographic visibility of the osteotomy, characterized the soft-tissue type of behavior of the bones. Hard-tissue like behaviour of the bones with resistance to torsion at the osteotomy site and radiographic obliteration of the osteotomy line occurred by 12 weeks, indicating complete union of the osteotomy. Our experiments demonstrate that elastic external fixation is preferable to the rigid compression plate. 相似文献
8.
以我所统一标准,确诊为“肝阳上亢证”者,进行微循环观察,肝阳上亢证者90例;阴虚阳上亢证者88例,健康对照组48例。观察发现肝阳上亢组与健康对照组及阴虚阳亢组与健康对照组均有显著性差异。通过卡方证明本检测数据可靠,微循环观测可作为“肝阳上亢证”的客观检测指标之一。 相似文献
9.
人癌干细胞集落形成测定常用双层琼脂平皿法。新法系采用园形玻璃毛细管法培养!可
以减少细胞用量及药物消耗。管内径为1.3mm,管长9.75cm,内盛15.000有核细胞/50μl,培养7~
14天。50例肿瘤活检标本生长成功率为88%,并可供化疗药物敏感性试验用。这种微量化检测具有
独特的优点,便于推广应用。 相似文献
10.
Tommi Sukuvaara Erkki M. J. Koski Aki Mäkivirta Aarno Kari 《Journal of clinical monitoring and computing》1994,10(2):117-126
A knowledge-based alarm system for intensive care monitoring was designed, built, tested on-line, and evaluated. The system is a functional prototype of a highly specific patient monitor providing alarms on hypovolemia, hyperdynamic state, left ventricular failure and hypoventilation. These intelligent alarm functions aim to maintain the quality of patient monitoring even if nurses' attention is temporarily reduced or focused elsewhere. The alarm system has an electronic access to data available in a multichannel patient monitor and the patient data management system of the intensive care unit. Median filtering, trend estimation, and rule-based reasoning are applied when processing the measured variables and estimating the patient's state. 相似文献