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81.
Laser endoscopic surgery, especially the effectiveness of photodynamic therapy (PDT) using Photofrin as a photosensitizer, has now achieved a status as effective treatment modality for lung cancer. Twenty-six lung cancer patients received the preoperative PDT for the purpose of either reducing the extent of resection or increasing operability. Bronchoscopical PDT is performed with topical anesthesia approximately 48 h after the intravenous injection of 2.0 mg/kg body weight of Photofrin. Operation was performed 2-9 weeks after initial PDT. The initial purpose of PDT, i.e. either to reduce the extent of resection or convert inoperable disease to operable status, was achieved in 22 out of 26 patients treated. The survival rate of T3 (main bronchus invasion) cases treated by surgery alone increased significantly from 50.9% to 60.0% with the application of preoperative PDT. This remarkable result may imply that this new option of PDT as preoperative laser irradiation may contribute to the management of advanced lung malignancy.  相似文献   
82.
Lymphocyte subpopulations in patients with hemophilia were analyzed. The results were compared with those in age- and sex-matched controls. The patients had been receiving blood and blood products including Factor VIII or Factor IX for a number of years as required at the time of the onset of the disease. Heparinized peripheral blood was used in direct tests for cell marker analysis with OKT4, OKT8 and OKT11 monoclonal antibodies. There were less OKT4+ cells in the hemophiliac blood as compared with the controls, while both the groups had the same number of OKT8+ cells. As a result, the OKT4/OKT8 ratio was markedly depressed in the hemophiliac group and the conversion of the OKT4/OKT8 ratio was observed in the group of patients receiving long-term therapy with anti-hemophiliac products. Alteration of lymphocyte subpopulations in patients with hemophilia in relation to antihemophiliac therapy was discussed.  相似文献   
83.
The pituitary adenylate cyclase-activating polypeptide (PACAP) is a neuropeptide of the vasoactive intestinal peptide/secretin/glucagon superfamily. Studies in two related patients with a partial trisomy 18p revealed three copies of the PACAP gene and elevated PACAP concentrations in plasma. The patients suffer from severe mental retardation and have a bleeding tendency with mild thrombocytopenia, and their fibroblasts show increased PACAP mRNA levels. The PACAP receptor (vasoactive intestinal peptide/pituitary adenylate cyclase-activating peptide receptor 1 [VPAC1]) in platelets and fibroblasts is coupled to adenylyl cyclase activation. Accordingly, we found increased basal cAMP levels in patients' platelets and fibroblasts, providing a basis for the reduced platelet aggregation in these patients. Megakaryocyte-specific transgenic overexpression of PACAP in mice correspondingly increased PACAP release from platelets, reduced platelet activation, and prolonged the tail bleeding time. In contrast, the PACAP antagonist PACAP(6-38) or a monoclonal PACAP antibody enhanced the collagen-induced aggregation of normal human platelets, and in PACAP knockout mice, an increased platelet sensitivity toward collagen was found. Thus, we found that PACAP modulates platelet function and demonstrated what we believe to be the first hemostatic defect associated with PACAP overexpression; our study suggests the therapeutic potential to manage arterial thrombosis or bleeding by administration of PACAP mimetics or inhibitors, respectively.  相似文献   
84.
Lymphocytes from a patient with Wiskott-Aldrich syndrome (WAS) were employed for a study of the intracellular viscosity and fluorescein permeability through the cell membrane by a fluorescence polarization spectrofluorometer, which was designed to calculate polarization value and permeable fluorescein intensity automatically. Fluorescein diacetate (FDA) was used as the indicator probe. The fluorogenic substrate is taken up by viable cells and converted to a fluorescent molecule, fluorescein, by intracellular esterase, where upon the fluorescein easily effluxes through the cell membrane. The response to stimulation with phytohemagglutinin (PHA) for 45 min led to a decreased polarization value (p-value) as compared to lymphocytes of healthy donors, and the fluorescein efflux through the cell membrane was greater than that of healthy donors. Fluorescein efflux from lymphocytes in the patient during 48 and 72 h incubation with or without PHA was markedly increased. In healthy donors, the degree of fluorescein permeability was not increased during the culture. These results indicate that intracellular viscosity of lymphocytes is altered in initial mitogenic stimulation, but that there was some abnormality in the fluorescein permeability properties through the cell membrane of lymphocytes in a patient with WAS.  相似文献   
85.
Adiponectin, an adipocyte-derived protein, has been suggested to play an important role in insulin sensitivity. We examined the association between insulin sensitivity (M value) evaluated by the euglycemic-hyperinsulinemic glucose clamp and adiponectin concentrations in 30 essential hypertensives (EHT) and 20 normotensives (NT) and investigated the effect of blockade of the renin-angiotensin system (RAS) on adiponectin concentrations. EHT were divided into 12 insulin-resistant EHT (EHT-R) and 18 non-insulin-resistant EHT (EHT-N) using mean-1 SD of the M value in NT. There were no intergroup differences in age, gender, and body mass index (BMI). EHT-R had significantly higher levels of insulin and triglyceride and lower levels of adiponectin than did NT and EHT-N. EHT-R had higher levels of free fatty acid and lower levels of high-density lipoprotein (HDL) cholesterol than did EHT-N. Adiponectin concentrations were positively correlated with M value and HDL cholesterol and negatively correlated with BMI, insulin, free fatty acid, and triglyceride but not with blood pressure. M value, BMI, and HDL cholesterol were independent determinants of adiponectin concentrations in multiple and stepwise regression analyses. Sixteen EHT were treated with an angiotensin-converting enzyme inhibitor (temocapril, 4 mg/d; n=9) or an angiotensin II receptor blocker (candesartan, 8 mg/d; n=7) for 2 weeks. Treatment with temocapril or candesartan significantly decreased blood pressure and increased M value and adiponectin concentrations but did not affect BMI and HDL cholesterol. These results suggest that hypoadiponectinemia is related to insulin resistance in essential hypertension and that RAS blockade increases adiponectin concentrations with improvement in insulin sensitivity.  相似文献   
86.
Few studies have investigated deployment‐related experiences of healthcare workers dispatched for medical humanitarian aid or attempted to assess their difficult living and working environments. This is the first study to develop and validate a scale to measure these kinds of difficulties, in 264 Japanese healthcare workers. The Humanitarian Aid Difficulty Scale was developed in three stages. First, an item pool was generated based on literature and expert reviews. The scale was then tested in a pilot study. Reliability and validity were identified through exploratory and confirmatory factor analysis and Cronbach's alpha. The scale consisted of 23 items across five factors based on exploratory factor analysis (cooperation, health status, infrastructure, culture and customs, and supplies and equipment). The total variance explained was 60.7%. Reliability of the five factors was acceptable and validity was supported by confirmatory factor analysis. Cronbach's alpha for the scale was 0.87. The scale may enable evaluation of the level of difficulty of the living and working environments of Japanese healthcare workers in medical humanitarian aid who are at a greater risk of distress.  相似文献   
87.

Background

Sulforaphane (SUL), a kind of isothiocyanate, has recently been focused due to its strong pro-apoptotic effect on cancer cells as well as tumor vascular endothelial cells (ECs). And recently, we demonstrated the induction of autophagy by colon cancer cells as a protective mechanism against SUL. In the present study, we aimed to investigate the possible role of autophagy induction by ECs as a defense mechanism against SUL.

Methods

Human umbilical vein endothelial cells (HUVECs) were used as the in vitro model of angiogenic ECs. The induction of autophagy was evaluated by the detection of acidic vesicular organelles (AVOs) by flow-cytometry, after the staining with acridine orange, as well as the detection of light chain 3(LC3) by Western blot. Finally, the functional implication of autophagy inhibition and SUL treatment in ECs was investigated by their ability to form vascular-like structures on Matrigel.

Results

Treatment of HUVECs with relatively low concentrations of SUL for 16 h resulted in the evident formation of AVOs and the recruitment of LC3 to autophagosomes, the pathognomonic features of autophagy. Co-treatment of cells with the specific autophagy inhibitor (3-methyladenine) potentiated the proapoptotic effect of SUL. And inhibition of autophagy potentiated the inhibitory effect of SUL on the ability of ECs to form capillary-like structures.

Conclusion

Similar to cancer cells, ECs induced autophagy in response to the pro-apoptotic agent, SUL, and the inhibition of autophagy potentiated the pro-apoptotic effect. These findings open premises for the use of autophagy inhibitors in combination with anti–angiogenic agents.  相似文献   
88.
Some factors play pathogenic roles in the development of restenosis after percutaneous coronary intervention (PCI). We measured and compared the ratio of elevated levels of regulated on activation normally T-cell expressed and secreted (RANTES), soluble (s) P-selectin, sE-selectin, s vascular cell adhesion molecule (VCAM)-1, s interleukin-2 receptor (IL-2R) and s tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) after PCI. Plasma levels of chemokines and soluble markers were measured before and 30 days after PCI in 85 patients (61 males and 24 females, aged 61 ± 7 years) who underwent PCI and who had repeated angiograms at a 6-month follow-up. Restenosis occurred in 29 (34.1%) patients. The significant and time-dependent increases in RANTES, sIL-2R and sVCAM-1 were observed in the restenosis group. However, there were no significant differences in sP-selectin and sE-selectin levels with or without restenosis. sTRAIL levels in patients with coronary artery disease were significantly higher than levels in normal controls. Furthermore, unlike the restenosis group, sTRAIL levels after PCI were significantly increased in the non-restenosis group, and sTRAIL levels correlated significantly with sVCAM-1 and sE-selectin. These findings suggest that restenosis development after PCI in patients with coronary artery disease involve the participation of RANTES and activated T-lymphocyte expressing CD25 after PCI, and sTRAIL may prevent this RANTES-dependent restenosis.  相似文献   
89.
Autophagy is a complex of adaptive cellular response that enhances cancer cell survival in the face of cellular stresses such as chemotherapy. Recently, chloroquine diphosphate (CQ), a widely used antimalarial drug, has been studied as a potential inhibitor of autophagy. Here, we aimed to investigate the role of CQ in potentiating the effect of 5-fluorouracil (5-FU), the chemotherapeutic agent of first choice for the treatment of colorectal cancer, in an animal model of colon cancer. The mouse colon cancer cell line colon26 was used. For the in-vivo study, colon26 cells were injected subcutaneously into BALB/c mice, which were treated with saline as a control, CQ (50 mg/kg/day), 5-FU (30 mg/kg/day), or the combination therapy (CQ plus 5-FU). The tumor volume ratio and body weight were monitored. After the sacrifice, tumor tissue protein extracts and tumor sections were prepared and subjected to immunoblotting for the analysis of autophagy-related and apoptosis-related proteins, and the terminal transferase uridyl end labeling assay. The combination of CQ resulted in the inhibition of 5-FU-induced autophagy and a significant enhancement in the 5-FU-induced inhibition of tumor growth. Furthermore, the combination treatment of CQ and 5-FU resulted in a significant increase in the ratio of apoptotic cells compared with other treatments. The expression levels of the proapoptotic proteins, namely Bad and Bax, were increased by the CQ treatment in the protein extracts from tumors. Our findings suggest that the combination therapy of CQ and 5-FU should be considered as an effective strategy for the treatment of colorectal cancer.  相似文献   
90.
Pituitary adenylate cyclase-activating polypeptide (PACAP) is a peptidergic neurotransmitter that is highly expressed in the nervous system. We have previously reported that a central injection of PACAP leads to changes in the autonomic nervous system tones including sympathetic excitation and parasympathetic inhibition. An anatomical study revealed that melanocortin and PACAP are colocalized in some hypothalamic nuclei. Here, we investigated the possible role of the melanocortin system in autonomic control by PACAP using SHU9119, an antagonist of the melanocortin receptors (MC3-R/MC4-R). Pretreatment with SHU-9119 did not affect the activating neural responses of adrenal, renal, and lumbar sympathetic nerves following a PACAP injection However, SHU9119 significantly eliminated the suppressing effect of a PACAP injection on gastric vagal nerve activity and excitation effects on liver and brown adipose tissue sympathetic nerve activities. These results suggest that the brain melanocortin system might play a key role in the control of thermogenic sympathetic outflows and digestive parasympathetic outflow by PACAP, but this system does not participate in the central effects of PACAP on cardiovascular function and neural activities of renal, adrenal, and lumbar sympathetic nerves.  相似文献   
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