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MALT1 is a key mediator of NF-κB signaling and a main driver of B-cell lymphomas. Remarkably, MALT1 is expressed in the majority of pancreatic ductal adenocarcinomas (PDACs) as well, but absent from normal exocrine pancreatic tissue. Following, MALT1 shows off to be a specific target in cancer cells of PDAC without affecting regular pancreatic cells. Therefore, we studied the impact of pharmacological MALT1 inhibition in pancreatic cancer and showed promising effects on tumor progression. Mepazine (Mep), a phenothiazine derivative, is a known potent MALT1 inhibitor. Newly, we described that biperiden (Bip) is a potent MALT1 inhibitor with even less pharmacological side effects. Thus, Bip is a promising drug leading to reduced proliferation and increased apoptosis in PDAC cells in vitro and in vivo. By compromising MALT1 activity, nuclear translocation of c-Rel is prevented. c-Rel is critical for NF-κB-dependent inhibition of apoptosis. Hence, off-label use of Bip or Mep represents a promising new therapeutic approach to PDAC treatment. Regularly, the Anticholinergicum Bip is used to treat neurological side effects of Phenothiazines, like extrapyramidal symptoms.  相似文献   
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Pexidartinib (PLX3397) is a colony-stimulating factor-1 receptor (CSF-1R) inhibitor under clinical evaluation for potential CNS tumor treatment. This study aims to evaluate plasma pharmacokinetic parameters and estimate CNS penetrance of pexidartinib in a non-human primate (NHP) cerebrospinal fluid (CSF) reservoir model. Five male rhesus macaques, each with a previously implanted subcutaneous CSF ventricular reservoir and central venous lines, were used. NHPs received a single dose of 40 mg/kg pexidartinib (human equivalent dose of 800 mg/m2), administered orally as 200 mg tablets. Serial paired samples of blood and CSF were collected at 0–8, 24, 48, and 72 h. Pexidartinib concentrations were assayed by Integrated Analytical Solutions, Inc. (Berkeley, CA, USA) using HPLC/MS/MS. Pharmacokinetic (PK) analysis was performed using noncompartmental methods. Samples from four NHPs were evaluable. Average (± SD) plasma PK parameters were as follows: Cmax = 16.50 (± 6.67) μg/mL; Tmax = 5.00 (± 2.58) h; AUClast = 250.25 (± 103.76) h*μg/mL; CL = 0.18 (± 0.10) L/h/kg. In CSF, pexidartinib was either quantifiable (n = 2), with Cmax values of 16.1 and 10.1 ng/mL achieved 2–4 h after plasma Tmax, or undetected at all time points (n = 2, LLOQCSF = 5 ng/mL). Pexidartinib was well-tolerated in NHPs, with no Grade 3 or Grade 4 toxicities. The CSF penetration of pexidartinib after single-dose oral administration to NHPs was limited.  相似文献   
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Definitive radiotherapy is an effective single-modality in T1 glottic cancer. Hypofractionated schemes could offer excellent results in a shorter treatment period. We aimed to evaluate the clinical outcomes and toxicity comparing conventional vs. hypofractionated radiotherapy treatment in T1N0M0-glottic cancer. Between Jan-1st, 2005 and August-1st, 2017, in a prospective cohort study, with 10-year follow-up, 138 patients were treated with conventional schedule 2 Gy/day, total dose 70 Gy/7 weeks (N = 71) or hypofractionated schedule 2, 2–2, 25 Gy/day, total dose 63, 8–63 Gy/5, 5 weeks (N = 67). Endpoints were clinical-response rate, local relapse-free survival (LRFS), laryngectomy-free survival (LFS), toxicity rates, relapse-free survival (RFS), metastasis-free survival (MFS), second tumour-free survival (2TFS), and overall survival (OS). All patients showed a complete clinical response. No differences were found for LRFS (p = 0.869), LFS (p = 0.975), RFS (p = 0.767), MFS (p = 0.601), 2TFS (p = 0.293), or OS (p = 0.685). Acute toxicity for skin and mucosae was similar (p = 0.550 and p = 0.698). Acute laryngeal toxicity was higher in the hypofractionation group (p = 0.004), due to an increase in slight moderate grade. No differences in late laryngeal edema were found (p = 0.989). Radiotherapy offers high rate survival, local control, and larynx preservation after 5–10-year follow-up. A hypofractionation could be preferable, since it offers the same results as conventional with fewer treatment sessions.  相似文献   
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Purpose

Many authors suggest that extremity soft tissue sarcomas (ESTS) do not change significantly in size during preoperative radiation therapy (RT). This cone beam computed tomography study investigates the justification to deliver the entire course with 1 initial RT plan by observing anatomic changes during RT.

Methods and Materials

Between 2015 and 2017, 99 patients with ESTS were treated with either curative (n = 80) or palliative intent (n = 19) with a regimen of at least 6 fractions. The clinical target volume to planning target volume margin was 1 cm. Action levels were assigned by radiation technicians. An extremity contour change of >1 cm and/or tumor size change >0.5 cm required a physician's action before the next fraction.

Results

A total of 982 cone beam computed tomography logfiles were studied. In 41 of 99 patients, the dose coverage of the initial treatment plan was fully satisfactory throughout the RT course. However, action levels were observed in 58 patients (59%). In 41 of these 58 patients, a contour increase of 5 to 23 mm was noted (29 tumor size increase only, 3 extremity contour increase, and 9 both). In 21 of 58 patients, a decrease of 5 to 33 mm was observed (20 tumor size decrease only and 1 tumor size decrease and extremity contour decrease). In 4 cases, contours initially increased and subsequently decreased. In 33 of 41 patients with increasing contours, the dose distribution adequately covered gross tumor volume because of the 1 cm planning target volume margin applied. For the remaining 8 patients (8%), the plan needed to be adapted.

Conclusions

ESTS volumes may change substantially during RT in 59% of all patients, leading to plan adaptations resulting from increased volumes in 8%. Daily critical observation of these patients is mandatory to avoid geographic misses because of increases in size and overdosing of normal tissues when masses shrink.  相似文献   
89.

Purpose

Understanding the attitudes of physicians toward the use of pre-exposure prophylaxis (PrEP) for HIV prevention among youth is critical to improving access to PrEP. We examined PrEP-related attitudes among physicians who provide primary care to 13- to 21-year-old adolescents.

Methods

Individual, in-depth, semistructured interviews were conducted with 38 physicians from adolescent medicine, family practice, internal medicine/medicine-pediatrics, obstetrics/gynecology, and pediatrics who care for any adolescents younger than 18 years. Interviews assessed familiarity with PrEP, perceived benefits and barriers to providing PrEP to adolescents, facilitating factors for prescribing PrEP, and likelihood of recommending and prescribing PrEP to adolescents.

Results

Mean age was 44.6 years (standard deviation 10.9). Fourteen physicians (37%) reported being somewhat or very familiar with PrEP. Perceived benefits of prescribing PrEP included decreased acquisition/rates of HIV, improved provision of sexual health services, and improved patient awareness of HIV risk. Barriers to PrEP were reported at the patient (e.g., lack of acceptability to patients), provider (e.g., concerns about patient adherence, safety/side effects, parents as a barrier to PrEP use), and system (e.g., high cost) levels. Facilitating factors for prescribing PrEP included low cost/coverage by insurance, physician education about PrEP, patient educational materials, and clinical guidelines for PrEP use in youth. A higher proportion of physicians reported being highly or somewhat likely to recommend (N = 16, 42%) than prescribe PrEP (N = 13, 34%).

Conclusions

In this study of primary care physician attitudes toward PrEP prescribing for adolescents, physicians identified numerous barriers to providing PrEP. Addressing these barriers may increase adolescents' access to PrEP.  相似文献   
90.
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