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91.
Hideyuki Masuda Makoto Kimura Akiko Nishioka Hiroshi Kato Akimichi Morita 《Journal of dermatological science》2019,93(2):109-115
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92.
Camilla Sandberg Albert G. Crenshaw Guilherme H. Elçadi Christina Christersson Joanna Hlebowicz Ulf Thilén Bengt Johansson 《The Canadian journal of cardiology》2019,35(12):1815-1823
BackgroundAdults with complex congenital heart disease (CHD) show reduced aerobic exercise capacity and impaired skeletal muscle function compared with healthy peers. Peripheral muscle factors are presumed to be important contributors to the aerobic capacity, but the mechanisms are poorly understood. The aim of the present study was to investigate differences between adults with CHD and controls in muscle oxygenation kinetics at rest, and during and after exercise.MethodsSeventy-four patients with complex CHD (mean age 35.6 ± 14.3 years, female n = 22) were recruited. Seventy-four age- and sex-matched subjects were recruited as controls. Muscle oxygenation was successfully determined on the anterior portion of the deltoid muscle using near-infrared spectroscopy in 65 patients and 71 controls. Measurements were made at rest, during isotonic shoulder flexions (0-90°) to exhaustion, and during recovery.ResultsThe patients with CHD performed fewer shoulder flexions (40 ± 17 vs 69 ± 40; P < 0.001), had lower muscle oxygen saturation (StO2) at rest (58 ± 18% vs 69 ± 18%; P < 0.001), slower desaturation rate at exercise onset (?9.7 ± 5.9 vs ?15.1 ± 6.5% StO2 × 3.5 s?1, P <0.001), and slower resaturation rate post exercise (4.0 ± 2.7 vs 5.4 ± 3.6% StO2 × 3.5 s?1; P = 0.009) compared with the controls.ConclusionsIn comparison with age- and sex-matched controls, adults with complex CHD had slower oxygenation kinetics. This altered skeletal muscle metabolism might contribute to the impaired skeletal muscle endurance capacity shown and thereby also to the reduced aerobic capacity in this population. 相似文献
93.
94.
Y. Chen B. Bai H. Yan F. Wen D. Qin G. Jander Q. Xia G. Wang 《Insect molecular biology》2019,28(3):380-391
Isopentenylation at A37 (i6A37) of some transfer RNAs (tRNAs) plays a vital role in regulating the efficiency and fidelity of protein synthesis. However, whether insects, which are well known for their highly efficient protein synthesis machinery, employ this regulatory mechanism remains uninvestigated. In the current study, a candidate tRNA isopentenyltransferase (IPT) gene with three alternative splicing isoforms (BmIPT1–BmIPT3) was identified in Bombyx mori (silkworm). Only BmIPT1 could complement a yeast mutant lacking tRNA IPT. Phylogenetic analysis showed that silkworm tRNA IPT is conserved in the Lepidoptera. BmIPT was expressed in all B. mori tissues and organs that were investigated, but was expressed at a significantly higher level in silk glands of the fourth instar compared to the first day of the fifth instar. Interestingly, BmIPT was expressed at a significantly higher level in the domesticated silkworm, B. mori, than in wild Bombyx mandarina in multiple tissues and organs. Knock‐down of BmIPT by RNA interference caused severe abnormalities in silk spinning and metamorphosis. Constitutive overexpression of BmIPT1 using a cytoplasmic actin 4 promoter in B. mori raised its messenger RNA level more than sixfold compared with nontransgenic insects and led to significant decreases in the body weight and cocoon shell ratio. Together, these results confirm the first functional tRNA IPT in insects and show that a suitable expression level of tRNA IPT is vital for silk spinning, normal growth, and metamorphosis. Thus, i6A modification at position A37 in tRNA probably plays an important role in B. mori protein synthesis. 相似文献
95.
96.
Allen H. Moffitt 《American journal of orthodontics and dentofacial orthopedics》2019,155(4):606.e1-606.e2
97.
Ángel Becerra Héctor Trujillo Lucía Valencia Aurelio Rodríguez‐Pérez 《Brazilian Journal of Anesthesiology》2019,69(2):200-203
Background and objectives
A prompt and effective management of trauma patient is necessary. The aim of this case report is to highlight the importance of intraoperative echocardiography as a useful tool in patients suffering from refractory hemodynamic instability no otherwise explained.Case report
A 41 year‐old woman suffered a car accident. At the emergency department, no abnormalities were found in ECG or chest X‐ray. Abdominal ultrasound revealed the presence of abdominal free liquid and the patient was submitted to urgent exploratory laparotomy. Nevertheless, she persisted suffering arterial hypotension and metabolic acidosis. Looking for the reason of her hemodynamic instability, intraoperative transthoracic echocardiography was performed, finding out the presence of pericardial effusion. Once the cardiac surgeon extracted pericardial clots, patient's situation improved clinically and analytically.Conclusion
Every anesthesiologist should be able to use the intraoperative echocardiography as an effective tool in order to establish the appropriate measures to promote the survival of patients suffering severe trauma. 相似文献98.
L. Hulshof D.P. Hack Q.C.J. Hasnoe B. Dontje I. Jakasa C. Riethmüller W.H.I. McLean W.M.C. van Aalderen B. van't Land S. Kezic A.B. Sprikkelman M.A. Middelkamp-Hup 《The British journal of dermatology》2019,180(3):621-630
Atopic dermatitis (AD, atopic eczema) is a very common skin condition affecting 10-20% of children. It affects children of all skin colours and seems to occur more often in Asian children and children with dark skin types. However, most research is performed on children with light skin types. This study, performed in Amsterdam, the Netherlands, aimed to investigate differences between AD in children with dark and light skin types. To study this, the investigators took tape strips from 53 AD children aged 0-12 years and 50 healthy children as control (comparison). Tape stripping is a painless procedure which is ideal to perform in children, in which a small round sticker is attached to the skin. When removing this special sticker, a thin layer of skin cells remains attached to the sticker, allowing the investigators to study several aspects of skin inflammation and skin barrier. The authors found that AD skin from children with light and dark skin have similar levels and types of skin inflammation. However, they found differences in skin barrier markers between these two groups. In light skinned children, markers of good skin barrier were lower in AD skin when compared to healthy children's skin, while in dark AD skin these skin barrier markers were not significantly different from healthy dark skin. This study showed that dark-skinned and light-skinned AD children are similar when it concerns skin inflammation, but in light skinned AD children the skin barrier dysfunction may play an additional role in the development of AD. This suggests that AD in light and dark skin has different mechanisms of development. 相似文献
99.
100.