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1.

Background

Photosensitizers used for photodynamic therapy (PDT) to treat dermatologic disease are metabolized into mainly protoporphyrin IX (PpIX), which has five absorption wavelength peaks: 410?nm, 510?nm, 545?nm, 580?nm, and 630?nm. Although only red light around 635?nm and blue light around 400?nm are used as light sources for PDT, the efficiency of PDT might be improved by using multiple wavelengths, including those that correspond to the other absorption peaks of PpIX. Furthermore, because the target disease often occurs on the face, a flexible-type light-source unit that can be fitted to the lesion without unnecessarily exposing the mucous membranes, e.g., the eyes, nostrils, and mouth, is preferred.

Objective

We investigated the efficacy of a flexible light-emitting diode (LED) unit that emits multiple wavelengths to improve PDT effects.

Methods

HaCaT cells were incubated with 5-ALA and subsequently irradiated with either a single wavelength or sequentially with two wavelengths. Cell viability and reactive oxygen species were analyzed. Nude mice were implanted with COLO679 cells by subcutaneous injection into the flank. 5-ALA was subcutaneously injected into the tumor. The tumor was irradiated with 50?J/cm2 (day 0) and assessed daily until day 21.

Results

The synergistic PDT effects of dual-wavelength irradiation and reactive oxygen species production were highest with the 405-nm and 505-nm wavelength combination. This dual wavelength combination was also the most effective in vivo.

Conclusion

We could therefore conclude that dual-wavelength PDT is an efficient strategy for improving the therapeutic effects of PDT. Using a flexible LED unit is expected to achieve more uniform irradiation of uneven areas.  相似文献   
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3.
Background and Aims: Video capsule endoscopy (VCE) has become increasingly important as a simple method for observing the entire small intestine. The indications for VCE are obscure gastrointestinal bleeding and investigation of Crohn’s disease (CD). However, the correlation between endoscopic findings obtained by VCE and clinical findings in known cases of CD is not clear, and we therefore investigated this in the present study. Patients and methods: In 30 patients with known CD (Crohn’s disease activity index [CDAI] 0–420; median = 158.3), double contrast enteroclysis (ENT) was performed 1–3 weeks prior to VCE. The relationship between the VCE findings and hematological analysis/CDAI was examined. Results: In 17 of 30 patients, the entire small intestine could be investigated by VCE, whereas in the remaining 13 patients the terminal ileum could not be investigated. The following exhibited positive correlations: total lesions and CDAI (correlation coefficient values: rs = 0.661, adjusted P < 0.0061), ulcers and C‐reactive protein (CRP) (rs = 0.607, adjusted P < 0.0061), total lesions and CRP (rs = 0.604, adjusted P < 0.0061). Conclusions: Analysis with VCE suggests that CDAI and CRP indicate the activity of intestinal lesions in patients with known CD, and that CRP, in particular, is associated with the activity of ulcerative lesions of the intestine. This may contribute to revised guidelines for VCE in the future.  相似文献   
4.
From April 1989 to December 2004, we performed liver biopsy on 475 patients and obtained biopsy proven 35 cases of non-alcoholic fatty liver. Among them, 18 cases were diagnosed as non-alcoholic steatohepatitis (NASH). During the last three years, we have tried to detect NASH using ultrasonography and elevated value of serum ferritin (> 300 ng/ml). All of the eligible 7 cases biopsied during the course were diagnosed as NASH. In these 7 cases, ALT levels improved after the body weight loss accompanied by the parallel decrease of serum ferritin levels. Measurement of serum ferritin is useful in the detection of NASH but the normal value of ferritin cannot rule out the possibility of NASH.  相似文献   
5.
Carbon monoxide (CO), a byproduct of heme catalysis, was shown to have potent cytoprotective and anti-inflammatory effects. In vivo recipient CO inhalation at low concentrations prevented ischemia/reperfusion (I/R) injury associated with small intestinal transplantation (SITx). This study examined whether ex vivo delivery of CO in University of Wisconsin (UW) solution could ameliorate intestinal I/R injury. Orthotopic syngenic SITx was performed in Lewis rats after 6 h cold preservation in control UW or UW that was bubbled with CO gas (0.1-5%) (CO-UW). Recipient survival with intestinal grafts preserved in 5%, but not 0.1%, CO-UW improved to 86.7% (13/15) from 53% (9/17) with control UW. At 3 h after SITx, grafts stored in 5% CO-UW showed improved intestinal barrier function, less mucosal denudation and reduced inflammatory mediator upregulation compared to those in control UW. Preservation in CO-UW associated with reduced vascular resistance (end preservation), increased graft cyclic guanosine monophosphate levels (1 h), and improved graft blood flow (1 h). Protective effects of CO-UW were reversed by ODQ, an inhibitor of soluble guanylyl cyclase. In vitro culture experiment also showed better preservation of vascular endothelial cells with CO-UW. The study suggests that ex vivo CO delivery into UW solution would be a simple and innovative therapeutic strategy to prevent transplant-induced I/R injury.  相似文献   
6.
We report a case of biliary cystadenocarcinoma which recurred 41 months postoperatively. A 60-year-old woman was admitted for further examination of multiple metastatic tumors and a large amount of ascites. Systemic administration of 5FU and CDDP caused her CEA level to decrease gradually and abdominal computed tomography revealed considerable reduction of the metastatic tumors and ascites. Since her general condition had improved, chemotherapy was continued in the outpatient clinic.  相似文献   
7.
OBJECTIVE: It is well documented that cardiopulmonary bypass (CPB) severely impairs cellular immunity. The objective of this study was to investigate the effect of prostaglandin E1 (PGE1) on cellular immunity after CPB. METHODS: Patients who underwent elective cardiac surgery were randomly divided into the PGE1 group (n=12) and the control group (n=12). In the PGE1 group, PGE1 was administered at 20 ng/kg/min from just after the induction of anesthesia to the end of surgery. Peripheral blood mononuclear cells (PBMCs) were taken before anesthesia and on postoperative days 1, 3 and 7 (POD 1, POD 3 and POD 7). Proliferation responses of T cells to phytohemagglutinin (PHA) and pure protein derivative (PPD) antigen were measured as indicators of cellular immunity. RESULTS: PGE1 significantly attenuated the impairment of both PHA and PPD response after cardiac surgery on POD 1 (PHA response, 30 +/- 21% vs. 53 +/- 32%, control vs. PGE, p=0.048; PPD response, 18 +/- 21% vs. 39 +/- 27%, control vs. PGE, p=0.046). The reduced glutathione content of PBMCs in the control group was significantly decreased on POD 1. CONCLUSION: PGE1 attenuated the impairment of cellular immunity after cardiac surgery with CPB by reducing oxidative stress on PBMCs.  相似文献   
8.
Leptin is a newly found hormone secreted by adipocytes that regulates food intake, thermogenesis, and body fat. We measured plasma leptin levels in 103 patients with chronic renal failure treated by hemodialysis and 167 age- and gender-matched healthy control subjects to examine the impact of renal failure on plasma leptin levels and the influence of leptin on body composition measured by dual-energy X-ray absorptiometry. Hemodialysis patients showed a significant decrease in both body fat mass and lean body mass compared with those of the control subjects. Plasma leptin was significantly elevated in the hemodialysis group over the controls. In both groups, leptin was higher in female than male subjects, and it correlated positively with percent body fat. The subjects were divided into six categories according to percent body fat, and plasma leptin levels were compared between the two groups in the same category. Leptin of hemodialysis patients was significantly higher than that of the control subjects in the percent body fat categories of 30 or greater, whereas there was no statistically significant difference in leptin concentrations in the lower percent body fat categories. This was also true in the comparison in each gender, and leptin levels in female subjects showed a more remarkable difference between the hemodialysis and control groups in obese categories. Multiple regression analysis in all subjects indicated that plasma leptin levels were independently affected by percent body fat, plasma insulin concentration, gender, and renal failure. The positive impact of renal failure on leptin remained significant in the subjects with percent body fat of 30 or greater in the multiple regression model, whereas it was no longer significant in the remaining lean subjects. In multiple regression analysis of factors affecting fat mass index and lean mass index, leptin level was selectively associated with fat mass index, but not with lean mass index, regardless of percent body fat ranges. These results indicate that renal failure is an important factor affecting plasma leptin levels, especially in obese female subjects, and that hyperleptinemia was closely related to fat mass but not to lean body mass in hemodialysis patients.  相似文献   
9.
A 16-year-old man was admitted to our hospital with nausea, general fatigue, and consciousness disturbance along with extreme hyperammoniemia eight days after the onset of symptoms. Familial history and the high concentration of orotic acid in urine lead us to a diagnosis of OTCD. We immediately initiated intensive treatment such as continuous hemodiafiltration and sodium benzoate administration; however, the patient died twelve days after admission. Since OTCD is not so rare and can be found in all ages, it should be considered fundamental for evaluation of hyperammoniemia. This case suggested that for a better prognosis of OTCD patients it is very important to prevent such an onset, and to make an as early as possible diagnosis and start to treatment.  相似文献   
10.
Big mitogen-activated protein kinase 1 (BMK1), also known as extracellular signal-regulated kinase 5 (ERK5), is a newly identified member of the mitogen-activated protein (MAP) kinase family. Recently, several studies have suggested that BMK1 plays an important role in the pathogenesis of cardiovascular disease. To clarify the pathophysiological significance of BMK1 in the process of vascular remodeling, we explored the molecular mechanisms of BMK1 activation in vascular smooth muscle cells (VSMCs). From the results of co-immunoprecipitation and immunoblotting analyses, it was found that platelet-derived growth factor (PDGF), a known potent mitogen, activated BMK1 and triggered the Gab1-SHP-2 interaction in rat aortic smooth muscle cells (RASMCs). The abrogation of SHP-2 phosphatase activity by transfection of the SHP-2-C/S mutant suppressed PDGF-stimulated BMK1 activation. Infection with an adenoviral vector expressing dominant-negative MEK5alpha, which can suppress PDGF-stimulated BMK1 activation to the control level, inhibited PDGF-induced RASMC migration. Moreover, we observed an increase of BMK1 activation in injured mouse femoral arteries. From these findings, it is suggested that BMK1 activation leads to VSMC migration induced by PDGF via Gab1-SHP-2 interaction, and that BMK1-mediated VSMC migration may play a role in the pathogenesis of vascular remodeling.  相似文献   
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