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51.
Microgravity culture condition reduces immunogenicity and improves function of pancreatic islets1 总被引:3,自引:0,他引:3
BACKGROUND: The failure of pancreatic islet allotransplants observed in almost all clinical attempts is related to poor initial islet function and allograft rejection. To remedy these problems we cultured islets in microgravity conditions to improve their function and to reduce their immunogenicity. METHODS: Fresh mouse islets or mouse islets cultured in stationary dishes or microgravity bioreactors were transplanted to streptozotocin-induced diabetic mouse recipients. RESULTS: Both allogeneic dish- or bioreactor-cultured islets survived more than 100 days compared with fresh allogeneic islets, which were rejected in less than 15 days. Islet titration studies revealed that 250 fresh or dish-cultured, but only 30 to 120 bioreactor-cultured, islets were necessary to produce euglycemia. Furthermore, glucose tolerance tests showed that bioreactor-cultured islets functioned better compared with fresh and dish-cultured islets on day 30 postgrafting. Immunostaining and transmission electron microscopy (TEM) analyses showed the gradual disappearance of dendritic cells in cultured islets compared with fresh islets. TEM revealed that the ultrastructure of islets from bioreactor, but not dish, appeared healthy and closely resembled fresh islets. Interestingly, TEM and scanning electron microscopy showed that only bioreactor-cultured islets developed unique and multiple nutritional channels between arrays of islet cells. TEM with colloidal lanthanum tracer revealed that only bioreactor islet cell cultures were devoid of tight junctional complexes, which may facilitate channel formation. CONCLUSION: Microgravity condition decreases immunogenicity and significantly improves the function of secretory cells. 相似文献
52.
Bialkowski J Szkutnik M Bermúdez-Cañete R Kusa J Regiec S Mullins CE 《Revista espa?ola de cardiología》2002,55(6):682-685
A 13-year-old girl with middle aortic syndrome caused by Takayasu's disease was treated by balloon angioplasty of the right renal artery stenosis and the implantation of 3 stents, 2 in the stenosed thoracic segment and 1 in the abdominal segment of the aorta. Spiral computed tomography one and two years after the stents were inserted showed that the disease had progressed despite treatment with immunosuppressants. 相似文献
53.
54.
Increased expression of leptin and the leptin receptor as a marker of breast cancer progression: possible role of obesity-related stimuli. 总被引:7,自引:0,他引:7
55.
Bogdan Jaremin Ewa Kotulak Maria Starnawska Stanislaw Tomaszunas 《Journal of travel medicine》1996,3(2):91-95
Background: The safety of life and work at sea depends, among other things, on the state of health of the members of the crew. Despite preliminary fitness selection, death at sea is still frequent. In the present paper, causes and circumstances of fatal cases at sea in the years 1985–1994 were analyzed for one Polish shipping company.
Methods: Analysis was based on medical documentation and reports of accidents prepared by health centers, the employer and the marine judiciary. The effects of work conditions, as well as disease, on the resulting death were taken into account. The data obtained were compared to the mortality in nonseafaring men of productive age.
Results: The most frequent causes of deaths were sea catastrophes, circulatory system diseases, injuries, and poisonings (a total of 85%). Next were suicides, "missings," and cerebral apoplexies. Seamen of 50 to 59 years of age died most often, primarily of myocardial infarction. Fatal events occurred in different places (mostly at sea, less frequently in port). Certain onboard occupations were identified as most dangerous for fatal accidents. The shipowner acknowledged 60% of the deaths as accidents at work. The effects of weather conditions, stress, overstrain, and lack of access to qualified medical assistance were analyzed. A relationship between diagnosed disease and death was found only in the case of myocardial infarction and cerebral apoplexy. In scarcely 15% of these cases were preliminary symptoms noticed, while behavioral and personality disturbances were earlier observed in the majority of suicides.
Conclusions: The ship has remained one of the most dangerous workplaces, and fatal cases are to a large extent related to specific labor conditions at sea. 相似文献
Methods: Analysis was based on medical documentation and reports of accidents prepared by health centers, the employer and the marine judiciary. The effects of work conditions, as well as disease, on the resulting death were taken into account. The data obtained were compared to the mortality in nonseafaring men of productive age.
Results: The most frequent causes of deaths were sea catastrophes, circulatory system diseases, injuries, and poisonings (a total of 85%). Next were suicides, "missings," and cerebral apoplexies. Seamen of 50 to 59 years of age died most often, primarily of myocardial infarction. Fatal events occurred in different places (mostly at sea, less frequently in port). Certain onboard occupations were identified as most dangerous for fatal accidents. The shipowner acknowledged 60% of the deaths as accidents at work. The effects of weather conditions, stress, overstrain, and lack of access to qualified medical assistance were analyzed. A relationship between diagnosed disease and death was found only in the case of myocardial infarction and cerebral apoplexy. In scarcely 15% of these cases were preliminary symptoms noticed, while behavioral and personality disturbances were earlier observed in the majority of suicides.
Conclusions: The ship has remained one of the most dangerous workplaces, and fatal cases are to a large extent related to specific labor conditions at sea. 相似文献
56.
57.
Koda M Przystupa W Jarzabek K Wincewicz A Kanczuga-Koda L Tomaszewski J Sulkowska M Wolczynski S Sulkowski S 《Oncology reports》2005,14(1):93-98
Disturbance in expression of estrogen receptors together with changing influence of growth factor receptors and apoptosis associated proteins plays a role in breast cancer development and progression. However, immunohistochemical detection and relationships among these proteins were not often considered in relation to breast cancer and a few evaluations of expression provided mismatching results and conclusions. Consequently, we examined by immunohistochemistry the expression of the insulin-like growth factor-I receptor (IGF-IR), estrogen receptor alpha (ERalpha) and apoptosis-associated proteins, Bcl-2 and Bax, in human primary breast cancer, as well as analyzing the relationships among these proteins. The positive immunostaining for IGF-IR, ERalpha, Bcl-2 and Bax was noted in 56, 63.8, 82.8 and 50% of tumors, respectively. We observed that IGF-IR negatively correlated with ERalpha in the group of all tumors and in axillary node negative cancer (p<0.03, p<0.05, respectively), but not in the subgroup of node positive cancer. Expression of ERalpha correlated positively with Bcl-2 and negatively with Bax proteins (p<0.0001, p<0.05, respectively). We did not note significant relationships between IGF-IR and Bcl-2, or IGF-IR and Bax proteins. We found that increased Bax expression was associated with positive lymph node status, pT2 stage and G3 grade of tumors. Knowledge about alterations in the IGF-IR expression and relations of the receptor to other biological factors could help in our understanding of breast cancer biology and the importance of the IGF-IR in cancer progression as well as in effective management of breast cancer. 相似文献
58.
Hypolipidemic drugs affect monocyte IL-1beta gene expression and release in patients with IIa and IIb dyslipidemia 总被引:1,自引:0,他引:1
Okopien B Huzarska M Kulach A Stachura-Kulach A Madej A Belowski D Zielinski M Herman ZS 《Journal of cardiovascular pharmacology》2005,45(2):160-164
Because atherosclerosis has been proven to be an inflammatory disease, it became obvious that the proper treatment of dyslipidemic patients should not only correct lipid parameters but also inhibit the inflammatory state. One of the crucial proinflammatory and procoagulant cytokines participating in the pathogenesis of atherosclerosis is interleukin-1beta (IL-1beta). Therefore, the aim of the study was to asses the effect of statin and fibrate therapy (for dyslipidemia IIa and IIb, respectively) on IL-1beta gene expression and monocyte release evaluated in each patient. Additionally, the effect of hypolipidemic therapy on fibrinolysis was evaluated. The study was carried out in 37 patients: 12 with biochemically confirmed type IIa dyslipidemia (treated with atorvastatin), 12 with type IIb dyslipidemia (treated with fenofibrate), and 13 age- and sex-matched normolipidemic persons (control). IL-1beta concentrations in cultured monocytes and PAI-1 (Plasminogen Activator Inhibitor) plasma levels were measured using the ELISA method. To evaluate the expression of IL-1beta gene in monocytes, a semiquantitive RT-PCR procedure was performed. The results were normalized with the expression of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) as a housekeeping gene. Although IL-1beta monocyte release was markedly elevated in patients with atherogenic dyslipidemias, IL-1beta gene expression was only slightly and nonsignificantly higher in the studied groups versus control. We have observed significant reduction of IL-1beta mRNA expression after 30-day treatment with the examined drugs (atorvastatin, 2.10 +/- 0.50 versus 1.05 +/- 0.15; P < 0.001, fenofibrate; 2.27 +/- 0.48 versus 1.23 +/- 0.27; P < 0.01). There was no significant difference between statin and fibrate effect on IL-1beta mRNA expression. Similarly, we have noticed significant reduction of IL-1beta release by cultured monocytes after 30-day statin therapy (133.0 +/- 5.7 pg/mL versus 77.0 +/- 3.6 pg/mL; P < 0.01) and fibrate therapy (143.9 +/- 6.5 pg/mL versus 86.2 +/- 5.9 pg/mL; P < 0.01). Besides this antiinflammatory effect, we have observed a 30% reduction of PAI-1 plasma levels in both treated groups. In conclusion, effective 1-month hypolipidemic therapy with atorvastatin or fenofibrate diminished plasma levels of proinflammatory and procoagulatory state markers. 相似文献
59.
OBJECTIVE: The human immunodeficiency virus (HIV) epidemic is a growing health care problem. The purpose of this study was to examine the relationship between HIV infection and trauma patient treatment, complications, and mortality. METHODS: The Pennsylvania Trauma Outcome Study database was used to identify trauma patients with known HIV-positive status (HP) and randomly selected age-matched controls (CL). Demographics, Injury Severity Score, Glasgow Coma Scale score, mechanism of injury, preexisting conditions, complications, mortality, hospital length of stay (HLOS), intensive care unit length of stay (ILOS), and operative interventions were compared. RESULTS: Demographics, vital signs on presentation, and Injury Severity Score were similar between the HP and CL groups. There was no difference in mortality between the two groups (3.6% vs. 3.1%, p = 0.6447). HP patients were more likely to present with penetrating injuries (22.6% vs. 15.8%, p < 0.0031) and had significantly fewer major orthopedic injuries than CL patients (p < 0.01). HP patients were more likely to have a history of a neurologic condition; chronic drug/alcohol use; psychiatric diagnosis; or liver, pulmonary, and/or renal disease (all p < 0.01). HP patients had more pulmonary complications (12.3% vs. 4.1%), renal complications, and infectious/septic complications (all p < 0.01) than controls. Infection/sepsis and pulmonary complications were associated with significant mortality in HP patients. HP patients underwent more thoracostomies (7.5% vs. 4.4%, p = 0.0235) and exploratory laparotomies (7.0% vs. 2.4%, p = 0.0002). HLOS (10.2 +/- 10 vs. 6.8 +/- 8.6 days, p = 0.001) and ILOS (2.3 +/- 7.2 vs. 1.5 +/- 4.9 days, p = 0.0178) were greater for HP patients. HP patients were less likely than controls to be discharged directly to home (67.8% vs. 82.7%, p = 0.0001). CONCLUSION: HP patients had more preexisting conditions and complications than controls. There was no difference in overall mortality between the two groups. However, pulmonary/infectious complications were associated with significant mortality in HP patients. HP patients consumed more health care resources than controls, as exemplified by greater ILOS and HLOS and more operative procedures. 相似文献
60.
In a recent issue of the Journal of Trauma, Kim et al. described their experience with the esophageal Doppler monitor (EDM) in major burn patients. Other authors have reported the historical development of the EDM, reviewed the technical and scientific aspects of this modality, and compared the EDM with the pulmonary arterial catheter (PAC). However, most studies exclude the bedside, practical aspects of EDM placement and use. We retrospectively reviewed our EDM utilization over the past 27 months, with emphasis on the practical aspects of its use, potential indications, and contraindications. The purpose of this paper is to share our EDM experience with the reader. 相似文献