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81.
82.

Objectives

Short successive periods of skeletal muscle disuse have been suggested to substantially contribute to the observed loss of skeletal muscle mass over the life span. Hospitalization of older individuals due to acute illness, injury, or major surgery generally results in a mean hospital stay of 5 to 7 days, during which the level of physical activity is strongly reduced. We hypothesized that hospitalization following elective total hip arthroplasty is accompanied by substantial leg muscle atrophy in older men and women.

Design and participants

Twenty-six older patients (75 ± 1 years) undergoing elective total hip arthroplasty participated in this observational study.

Measurements

On hospital admission and on the day of discharge, computed tomographic (CT) scans were performed to assess muscle cross-sectional area (CSA) of both legs. During surgery and on the day of hospital discharge, a skeletal muscle biopsy was taken from the m. vastus lateralis of the operated leg to assess muscle fiber type–specific CSA.

Results

An average of 5.6 ± 0.3 days of hospitalization resulted in a significant decline in quadriceps (?3.4% ± 1.0%) and thigh muscle CSA (?4.2% ± 1.1%) in the nonoperated leg (P < .05). Edema resulted in a 10.3% ± 1.7% increase in leg CSA in the operated leg (P < .05). At hospital admission, muscle fiber CSA was smaller in the type II vs type I fibers (3326 ± 253 μm2 vs 4075 ± 279 μm2, respectively; P < .05). During hospitalization, type I and II muscle fiber CSA tended to increase, likely due to edema in the operated leg (P = .10).

Conclusions

Six days of hospitalization following elective total hip arthroplasty leads to substantial leg muscle atrophy in older patients. Effective intervention strategies are warranted to prevent the loss of muscle mass induced by short periods of muscle disuse during hospitalization.  相似文献   
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Bortezomib-induced peripheral neuropathy (BIPN) is a common toxicity associated with the treatment of multiple myeloma (MM), typically requiring dose reduction, delay, or cessation of treatment protocol. This systematic review aimed to investigate risk factors, trends, and variability associated with the development of BIPN. Searches were undertaken using Medline, PubMed, Cochrane Central Register of Controlled Trials, Embase, Scopus, and Web of Science. Additional studies were identified by investigating authors' bibliographic references cited by original and review articles. Articles that reported on neuropathy in phase III randomised control trials involving bortezomib in any treatment arm for the treatment of MM were included in this review. A total of 43 full text articles met criteria, which examined 23 phase III trials (N = 8218). Overall incidence of neuropathy ranged from 8.4% to 80.5% (median = 37.8%) and severe neuropathy (grade 3-4) ranged from 1% to 33.2% (median = 8%). Similar reports of neuropathy of any grade and severe neuropathy were observed between the newly diagnosed and relapsed cohort. Bortezomib regimens with reduced dose intensity were associated with reduced neuropathy incidence. Increased cumulative dosing levels, intravenous compared with subcutaneous administration and combination therapy with thalidomide were associated with higher rates of BIPN. This analysis revealed that BIPN is a significant toxicity. More sensitive measures are required to capture the incidence and severity of BIPN. Better understanding of risk factors and reversibility profiles will minimise the number of cancer survivors living with residual treatment side effects.  相似文献   
85.
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   
86.
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   
87.
Objectives: Increases in astrocytes and one of their markers, glial fibrillary acidic protein (GFAP) have been reported in the brains of patients with Alzheimer’s disease (AD). N-3 polyunsaturated fatty acids (PUFA) modulate neuroinflammation in animal models; however, their effect on astrocytes is unclear.

Methods: Fat-1 mice and their wildtype littermates were fed either a fish oil diet or a safflower oil diet deprived of n-3 PUFA. At 12 weeks, mice underwent intracerebroventricular infusion of amyloid-β 1-40. Astrocyte phenotype in the hippocampus was assessed at baseline and 10 days post-surgery using immunohistochemistry with various microscopy and image analysis techniques.

Results: GFAP increased in all groups in response to amyloid-β, with a greater increase in fish oil-fed mice than either fat-1 or wildtype safflower oil-fed mice. Astrocytes in this group were also more hypertrophic, suggesting increased activation. Both fat-1- and fish oil-fed mice had greater increases in branch number and length in response to amyloid-β infusion than wildtype safflower animals.

Conclusion: Fish oil feeding, and to a lesser extent the fat-1 transgene, enhances the astrocyte activation phenotype in response to amyloid-β 1-40. Astrocytes in mice fed fish oil were more activated in response to amyloid-β than in fat-1 mice despite similar levels of hippocampal n-3 PUFA, which suggests that other fatty acids or dietary factors contribute to this effect.  相似文献   

88.
Uptake of colorectal cancer screening remains suboptimal. Mailed fecal immunochemical testing (FIT) offers promise for increasing screening rates, but optimal strategies for implementation have not been well synthesized. In June 2019, the Centers for Disease Control and Prevention convened a meeting of subject matter experts and stakeholders to answer key questions regarding mailed FIT implementation in the United States. Points of agreement included: 1) primers, such as texts, telephone calls, and printed mailings before mailed FIT, appear to contribute to effectiveness; 2) invitation letters should be brief and easy to read, and the signatory should be tailored based on setting; 3) instructions for FIT completion should be simple and address challenges that may lead to failed laboratory processing, such as notation of collection date; 4) reminders delivered to initial noncompleters should be used to increase the FIT return rate; 5) data infrastructure should identify eligible patients and track each step in the outreach process, from primer delivery through abnormal FIT follow-up; 6) protocols and procedures such as navigation should be in place to promote colonoscopy after abnormal FIT; 7) a high-quality, 1-sample FIT should be used; 8) sustainability requires a program champion and organizational support for the work, including sufficient funding and external policies (such as quality reporting requirements) to drive commitment to program investment; and 9) the cost effectiveness of mailed FIT has been established. Participants concluded that mailed FIT is an effective and efficient strategy with great potential for increasing colorectal cancer screening in diverse health care settings if more widely implemented.  相似文献   
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