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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.
Journal of Artificial Organs - We encountered a case of unstable predilution online HDF due to elevated transmembrane pressure (TMP) when performing constant-speed predilution online...  相似文献   
4.

Viruses are believed to be ubiquitous; however, the diversity of viruses is largely unknown because of the bias of previous research toward pathogenic viruses. Deep sequencing is a promising and unbiased approach to detect viruses from animal-derived materials. Although cranes are known to be infected by several viruses such as influenza A viruses, previous studies targeted limited species of viruses, and thus viruses that infect cranes have not been extensively studied. In this study, we collected crane fecal samples in the Izumi plain in Japan, which is an overwintering site for cranes, and performed metagenomic shotgun sequencing analyses. We detected aviadenovirus-like sequences in the fecal samples and tentatively named the discovered virus crane-associated adenovirus 1 (CrAdV-1). We determined that our sequence accounted for approximately three-fourths of the estimated CrAdV-1 genome size (33,245 bp). The GC content of CrAdV-1 genome is 34.1%, which is considerably lower than that of other aviadenoviruses. Phylogenetic analyses revealed that CrAdV-1 clusters with members of the genus Aviadenovirus, but is distantly related to the previously identified aviadenoviruses. The protein sequence divergence between the DNA polymerase of CrAdV-1 and those of other aviadenoviruses is 45.2–46.8%. Based on these results and the species demarcation for the family Adenoviridae, we propose that CrAdV-1 be classified as a new species in the genus Aviadenovirus. Results of this study contribute to a deeper understanding of the diversity and evolution of viruses and provide additional information on viruses that infect cranes, which might lead to protection of the endangered species of cranes.

  相似文献   
5.
This study examined the influence of medial implant location in three-unit posterior cantilever fixed partial dentures (FPDs) on stress distribution in mandibular bone surrounding two implants. A three-dimensional finite element model that included three-unit FPD and two cylindrical-type implants (4 mm in diameter and 10 mm in length) osseointegrated in the posterior mandible, was digitized. Five different models were created according to the medial implant location between the missing second premolar and the first molar location. The distal implant was fixed at the missing second molar location. Oblique bite force of 100 N at 30 degrees buccal to the vertical direction was directed on each of three artificial teeth, respectively and simultaneously, while the lower surface of the mandible was fixed. The maximum equivalent stress in the cortical and the trabecular bone generally increased as the medial implant shifted to a distal position. Under the simultaneous bite force, relatively low maximum stresses within the cortical bone: between 55 MPa and 57 MPa, were shown in the models with the medial implant placed within the range of one implant diameter from the most medial position, while higher maximum stresses: between 64 MPa and 73 MPa, were demonstrated with more distally placed medial implants. The results suggest that reasonably low mechanical stress in the surrounding bone may be assured when the medial implant is placed in the range between the missing second premolar position and one implant diameter distal from that location.  相似文献   
6.
Salivary duct carcinoma (SDC) is a distinctive and aggressive neoplasm. The most frequent site of origin is the parotid gland, followed by the submandibular gland. SDC originating in the minor salivary glands, particularly in the ectopic glands within the mandible, is extremely rare. We describe a 62-year-old man with SDC in the mandible, who presented with a painless lump in the right submandibular region (later identified as lymph node metastasis) and ipsilateral mental nerve palsy. Histologic examination after ablative surgery revealed SDC originating in the mandible and cervical nodal metastases spreading to levels I-III. The patient remains alive 59 months after presentation as a result of postoperative full-dose irradiation and regular intensive chemotherapy using TXT, 5-FU, and CDDP. However, the patient has local recurrence and distant metastases to the lung and brain. In this report, we also discuss the specific diagnostic criteria and developmental theories of intraosseous salivary gland tumors.  相似文献   
7.
8.
We compared palatal sensitivity after push-back palatoplasty in patients operated on with a conventional mucoperiosteal flap and with a supraperiosteal flap. We studied 37 patients, whose mean age was 18 years (range 11-28), with unilateral cleft lip, alveolus, and palate who required palatoplasty at our clinic; 18 patients had a supraperiosteal, and 19 a mucoperiosteal flap. Thresholds of palatal sensitivity were measured with Semmes-Weinstein monofilaments. The mean values of thresholds of palatal sensitivity in patients who had a push-back palatoplasty were higher than those in a normal control group. The mean values for patients who had a supraperiosteal flap were significantly lower than those who had a mucoperiosteal flap.  相似文献   
9.
OBJECTIVE: To compare cross-national differences of dental health behaviour among dental hygiene students. DESIGN: Cross-cultural differences. Setting: United States (USA) and Korea. SUBJECTS AND METHODS: One hundred and twenty-six dental hygiene students in USA and 246 in Korea were surveyed using the Hiroshima University-Dental Behavioural Inventory (HU-DBI) (in English and Korean versions respectively). RESULTS: There were considerable differences in oral health behaviour between USA and Korean dental hygiene students. Of great significance were findings that while only a small proportion of the USA students (1%) reported gum bleeding when they brushed their teeth, 37% of the Korean students did so (P<0.001). Furthermore, only 19% of the Korean students had been told by their dentist that they were performing a high level of plaque control, contrasted with 76% of the USA students. Logistic regression model showed that it was possible to distinguish USA students from Korean peers with a probability of more than 90% by using the HU-DBI. CONCLUSIONS: There were considerable differences in dental health attitudes/behaviour among dental hygiene students in the two countries. The variation in the favourable attitudes/behaviour toward oral health appeared to reflect the students' clinical training experience in Korea.  相似文献   
10.
One hundred and two dentate patients with type II diabetes mellitus and 98 non-diabetic subjects were examined for oral conditions and metabolic state. Self-reported health behaviour was analysed. From factor analysis four factors emerged: general health behaviour (GHB), perceived fatigue (PF), diet control (DC) and regular diet (RD). In diabetics PF, DC and RD were significantly higher than that in non-diabetics. Patients with diabetes were more likely to control their disease through a programme of decreased kilojoule intake leading to weight management. However, they tended to tire. The mean gingivitis index was significantly higher (p<0.01) among diabetics (2.39) than among nondiabetics (1.99). The number of missing teeth was significantly higher (p<0.01) for diabetics (6.7) when compared with non-diabetics (4.3). On the other hand, aetiological factors (plaque, calculus) and the level of dental health behaviour as expressed in the HU-DBI scores were similar. Probing pocket depth did not differ statistically between groups. The increasing number of missing teeth in diabetics may primarily result from severe periodontitis with tooth mobility or deep pockets. Findings in this study suggest that the difference in the severity of periodontitis between diabetics and non-diabetics was significant although aetiological factors and the level of dental health behaviour were similar.  相似文献   
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