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1.
International Journal of Clinical Oncology - This multi-institutional clinical trial evaluated the feasibility of intensity-modulated radiotherapy (IMRT) for patients with locally advanced...  相似文献   
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  1. Trastuzumab deruxtecan (DS-8201a) is an antibody-drug conjugate (ADC) composed of a monoclonal antibody targeting human epidermal growth factor receptor 2 (HER2) conjugated to a topoisomerase I inhibitor (DXd) at a drug-to-antibody ratio (DAR) of 7-8. Here, we examined the pharmacokinetic (PK) profiles of DS-8201a and DXd in cynomolgus monkeys, a cross-reactive species.

  2. Following intravenous (iv) administration of DS-8201a, the linker was stable in plasma, and systemic DXd exposure was low. DXd was rapidly cleared following iv dosing. Biodistribution studies revealed that intact DS-8201a was present mostly in the blood without tissue-specific retention. The major pathway of excretion for DXd was the faecal route following iv administration of radiolabelled DS-8201a. The only detectable metabolite in the urine and faeces was unmetabolized DXd. DXd is a substrate of organic anion transporting polypeptides, P-gp, and breast cancer resistance protein.

  3. In conclusion, the stable linker in circulation and the high clearance of DXd upon release resulted in the low systemic exposure to DXd. Furthermore, the minimal tissue-specific retention and rapid excretion of DXd into faeces as its unmetabolized form with potentially limited impact on drug???drug interaction as a victim were also critical elements of the PK profile of DS-8201a.

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8.

Objective

The purpose of this study was to identify the risk factors of cognitive impairment in pediatric epilepsy patients with focal cortical dysplasia (FCD).

Methods

77 patients with histopathologically confirmed FCD were studied. The statistical relationship between cognition levels and clinical factors at presurgical evaluation was analyzed. Cognitive function was evaluated by development quotient or intelligence quotient (DQ-IQ).

Results

Ages at seizure onset were younger than 15?years (mean?±?SD; 5.0?±?4.2?years). Mean disease duration was 14.5?±?8.5?years. Mean age at pre-surgical DQ-IQ evaluation was 34.8?±?10.7?years. Mean DQ-IQ was 60.5?±?20.5, and 41 of 77 (53.2%) patients had mental retardation (DQ-IQ?<?70). Younger seizure onset and seizure clustering were significantly associated with lower DQ-IQ (p?<?0.001). A multiple regression study identified higher seizure frequency pattern, a history of epileptic spasm and status epilepticus as aggravating factors of DQ-IQ decline (R2?=?0.63, p?<?0.001). On the other hand, the risk was decreased in patients with habitual focal aware seizure and transient seizure-free periods up to 6?months in the course of epilepsy. FCD location (FCD site, extent of radiological lesion and laterality) and histopathology of FCD did not affect DQ-IQ.

Conclusions

Our study suggests that seizure characteristics including higher seizure frequency pattern, a history of epileptic spasm, status epilepticus, seizure clustering and early onset of seizure are risk factors of cognitive impairment in FCD patients.  相似文献   
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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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