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1.
Anastasia Kariagina Elena Morozova Reyhane Hoshyar Mark D. Aupperlee Mitchell A. Borin Sandra Z. Haslam Richard C. Schwartz 《Oncotarget》2020,11(48):4465
Benzophenone-3 is a putative endocrine disrupting chemical and common ingredient in sunscreens. The potential of endocrine disrupting chemicals to act as agonists or antagonists in critical hormonally regulated processes, such as mammary gland development and mammary tumorigenesis, demands evaluation of its potential in promoting breast cancer. This study identifies the effects of BP-3 on mammary tumorigenesis with high-fat diet during puberty versus adulthood in Trp53-null transplant BALB/c mice. Benzophenone-3 exposure yielded levels in urine similar to humans subjected to heavy topical sunscreen exposure. Benzophenone-3 was protective for epithelial tumorigenesis in mice fed lifelong low-fat diet, while promotional for epithelial tumorigenesis in mice fed adult high-fat diet. Benzophenone-3 increased tumor cell proliferation, decreased tumor cell apoptosis, and increased tumor vascularity dependent on specific dietary regimen and tumor histopathology. Even in instances of an ostensibly protective effect, other parameters suggest greater risk. Although benzophenone-3 seemed protective on low-fat diet, spindle cell tumors arising in these mice showed increased proliferation and decreased apoptosis. This points to a need for further studies of benzophenone-3 in both animal models and humans as a potential breast cancer risk factor, as well as a more general need to evaluate endocrine disrupting chemicals in varying dietary contexts. 相似文献
2.
Justin J. Mitchell 《Arthroscopy》2019,35(7):2048-2050
Since its inception in the early 1980s, the microfracture procedure has been successfully used throughout the body to treat isolated full-thickness cartilage lesions. Although treatment of such injuries can be challenging, and outcomes variable, microfracture has afforded surgeons the ability to treat cartilage lesions in a single-stage fashion at the time of treatment for concomitant injuries. Whereas most research relating to the use of microfracture has focused on managing lesions in the knee, there continues to be interest in applying the same principles in other regions of the body. With the recent enthusiasm and procedural increase in hip arthroscopy and hip preservation procedures, evaluating the use of microfracture in the femoroacetabular joint is the next logical step in establishing treatment principles for cartilage defects in this location. Although we continue to innovate as orthopedic surgeons, and there have been recent declines in ardor for the use of microfracture, this sentiment has arisen only after decades of research and clinical advances. Because of this, continued work will be necessary to understand the limits of the microfracture procedure in hip preservation surgery. Early outcome studies are encouraging and continue to be an important platform on which to lay the foundation for further research and refinement of techniques and indications. 相似文献
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Kevin Messacar Stacey L Hamilton Andrea M. Prinzi Jessica C Mitchell Erik D Beil Elaine B. Dowell Samuel R. Dominguez 《Diagnostic microbiology and infectious disease》2019,93(1):22-23
The FilmArray Blood Culture Identification Panel was validated for nonblood sterile site specimens with clinical impact of rapid identification compared to conventional diagnostics. The panel accurately identified target organisms from 98% of positive broth cultures a median 1.1?day faster than conventional techniques (P?<?0.0001) with potential clinical impact in 22% of cases. 相似文献
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J.A. Hannam S.J. Mitchell D. Cumin C. Frampton A.F. Merry M.R. Moore C.J. Kruger 《British journal of anaesthesia》2019,122(2):198-205
Background
Etomidate is frequently selected over propofol for induction of anaesthesia because of a putatively favourable haemodynamic profile, but data confirming this perception are limited.Methods
Patients undergoing cardiac surgery were randomised to induction of anaesthesia with propofol or etomidate. Phase I (n=75) was conducted as open-label, whereas Phase II (n=75) was double blind. Mean arterial blood pressure (MAP) and boluses of vasopressor administered after induction were recorded. The primary endpoint was the area under the curve below baseline MAP (MAP-time integral) during the 10 min after induction. Secondary endpoints were the use of vasopressors over the same period, and the effect of blinding on the aforementioned endpoints. Groups were compared using regression models with phase and anaesthetist as factors.Results
The mean difference between etomidate and propofol in the MAP-time integral below baseline was 2244 mm Hg s (95% confidence interval, 581–3906; P=0.009), representing a 34% greater reduction with propofol. Overall, vasopressors were used in 10/75 patients in the etomidate group vs 21/75 in the propofol group (P=0.38), and in 20/74 patients during the blinded phase vs 11/76 during the open-label phase (P=0.31). The interaction between randomisation and phase (open-labelled or blinded) was not significant for either primary (P=0.73) or secondary endpoints (P=0.90).Conclusions
Propofol caused a 34% greater reduction in MAP-time integral from baseline after induction of anaesthesia than etomidate, despite more frequent use of vasopressors with propofol, confirming the superior haemodynamic profile of etomidate in this context. The proportion of patients receiving vasopressors increased slightly, albeit not significantly, in both groups in the blinded phase.Clinical trial registration
Australian and New Zealand Clinical Trials Registry, ACTRN12614000717651. 相似文献10.
Christopher B. Forrest Joseph J. Zorc JeanHee Moon Ramya Pratiwadi Brandon D. Becker Mitchell G. Maltenfort 《The Journal of asthma》2019,56(5):534-542
Objective: To evaluate the reliability and validity of the PROMIS Pediatric Global Health scale, a 7-item measure of perceived physical, mental, and social health, in children with asthma. Methods: From February 2014 to February 2015, convenience samples of 8–17 year-old children (n = 182) and parents of 5–17 year-old children (n = 328) visiting an emergency department for treatment of asthma were enrolled. The Asthma Control Test was used to characterize children as controlled versus not controlled, and the PROMIS Asthma Impact Scale was used to assess asthma symptoms' impact on functional status. We conducted longitudinal analyses among 92 children and 218 parents at 3 weeks, and 74 children and 171 parents at 8 weeks after enrollment. Results: The PGH-7 reliability ranged from 0.66 to 0.81 for child-report and 0.76 to 0.82 for parent-proxy. In cross-sectional analyses, children with controlled asthma had PGH-7 scores 0.40–0.95 standard deviation units higher than those who were uncontrolled. The PGH-7 was responsive to changes in overall general health between time points, with moderate effect sizes (0.5–0.6 standard deviation units). In longitudinal analyses, PGH-7 scores were no different between those who stayed uncontrolled versus became controlled at 3 weeks of follow-up; however, by 8 weeks of follow-up, the differences between these groups were 0.7–0.8 standard deviation units, indicative of large effects. Conclusions: The PGH-7 is a reliable and valid patient-reported outcome for assessing general health among children with asthma. It is a useful complement to other asthma-specific outcome measures. 相似文献