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31.
32.
Anna-Maria Lutz Rüdiger Hampe Malgorzata Roos Nina Lümkemann Marlis Eichberger Bogna Stawarczyk 《The Journal of prosthetic dentistry》2019,121(1):166-172
Statement of problem
Polymeric material for 3-dimensional printing can be used to fabricate occlusal devices. However, information about fracture resistance and wear is scarce.Purpose
The purpose of this in vitro study was to investigate the fracture resistance and 2-body wear of 3-dimensional–printed (3DP) (FotoDent splint; Dreve Dentamid GmbH), milled polymethylmethacrylate (CAM) (Temp Basic; Transpa 95H16, Zirkonzahn GmbH), and conventionally fabricated polymethylmethacrylate (CAST) (Castdon; Dreve Dentamid GmbH) occlusal devices.Material and Methods
A total of 96 occlusal devices were prepared according to the 3 different manufacturing techniques 3DP, CAM, and CAST (n=32). For each manufacturing technique, specimens were further divided into initial fracture resistance tests (n=16) and artificial aging in the mastication simulator (50 N, 37°C) with 2-body wear followed by fracture resistance tests (n=16). The fracture resistance was determined using a universal testing machine (1 mm/min). The wear was measured after 20?000 and 120?000 mastication cycles with the replica technique, mapped with a laser scanner, and quantified in R software. Data were analyzed using a 2-way ANOVA followed by a 1-way ANOVA with Scheffé or Games-Howell post hoc tests, repeated measures ANOVA with corrected Greenhouse-Geisser P values, and the Levene, Mann-Whitney, and paired t tests (α=.05).Results
CAM presented higher initial fracture resistance than 3DP or CAST (P<.001). After mastication simulation, CAM followed by 3DP showed higher fracture resistance than CAST (P<.001). Mastication simulation decreased the fracture resistance for CAM and CAST (P<.001) but not for 3DP (P=.78). Three-dimensional–printed occlusal devices showed the highest material volume loss, followed by CAM and the lowest in CAST (P<.001).Conclusions
Three-dimensional–printed occlusal devices showed lower wear resistance and lower fracture resistance than those milled or conventionally fabricated. Therefore, only short-term application in the mouth is recommended. Further developments of occlusal device material for 3-dimensional printing are necessary. 相似文献33.
Chancellor F. Gray Hernan A. Prieto Justin T. Deen Hari K. Parvataneni 《The Journal of arthroplasty》2019,34(2):206-210
Background
Revision total joint arthroplasty (TJA) is associated with increased readmissions, complications, and expense compared to primary TJA. Bundled payment methods have been used to improve value of care in primary TJA, but little is known of their impact in revision TJA patients. The purpose of this study is to evaluate the impact of a care redesign for a bundled payment model for primary TJA on quality metrics for revision patients, despite absence of a targeted intervention for revisions.Methods
We compared quality metrics for all revision TJA patients including readmission rate, use of post–acute care facility after discharge, length of stay, and cost, between the year leading up to the redesign and the 2 years following its implementation. Changes in the primary TJA group over the same time period were also assessed for comparison.Results
Despite a volume increase of 37% over the study period, readmissions declined from 8.9% to 5.8%. Use of post–acute care facilities decreased from 42% to 24%. Length of stay went from 4.84 to 3.92 days. Cost of the hospital episode declined by 5%.Conclusion
Our health system experienced a halo effect from our bundled payment-influenced care redesign, with revision TJA patients experiencing notable improvements in several quality metrics, though not as pronounced as in the primary TJA population. These changes benefitted the patients, the health system, and the payers. We attribute these positive changes to an altered institutional mindset, resulting from an invested and aligned care team, with active physician oversight over the care episode. 相似文献34.
Lindsay A. Weiner Adam C. Richardson Semhar Z. Tewelde 《The Journal of emergency medicine》2019,56(4):e43-e46
Background
Spontaneous spinal and intracranial subdural hematomas are rarely reported, especially occurring simultaneously. Anticoagulation use has been associated with spontaneous hemorrhages. Prompt diagnosis is required to prevent permanent neurological sequelae. In this case report, we describe a spontaneous spinal and intracranial subdural hematoma in a woman taking warfarin and initially presenting with severe vaginal pain.Case Report
A 42-year-old woman who had a history of mechanical valve replacement and was therefore taking warfarin, came to an emergency department for relief of severe vaginal pain. Mild concurrent lumbar pain increased concern about spinal pathology, so magnetic resonance imaging of her spine was performed. It revealed a subdural hematoma extending from L1–S1 with arachnoiditis, which suggested intracranial pathology, though the patient had no complaint of a headache. Computed tomography of her brain demonstrated a large right subdural hemorrhage with midline shift. Subsequent imaging revealed no aneurysm or source of the intracranial bleeding. We concluded that the patient experienced spontaneous anticoagulation-related intracranial hemorrhage resulting in lumbar subdural hematoma and arachnoiditis with referred vaginal pain.Why Should an Emergency Physician Be Aware of This?
Pelvic, vaginal, or perineal pain may be the presenting symptom in patients with lower spinal pathology. It is important to consider causes other than gynecological ones in the differential diagnosis of these patients, as well as to be cognizant of the relationship between spinal and intracranial subdural hemorrhages. In patients with back pain or radiating lumbar pain, especially coupled with neurological effects, clinicians should consider spinal subdural hemorrhage and arachnoiditis to expedite imaging studies and treatment of these rare entities. 相似文献35.
David C. Johnson Steven S. Raman Sohrab A. Mirak Lorna Kwan Amirhossein M. Bajgiran William Hsu Cleo K. Maehara Preeti Ahuja Izak Faiena Aydin Pooli Amirali Salmasi Anthony Sisk Ely R. Felker David S.K. Lu Robert E. Reiter 《European urology》2019,75(5):712-720
Background
Multiparametric magnetic resonance imaging (mpMRI) undoubtedly affects the diagnosis and treatment of localized prostate cancer (CaP). However, clinicians need a better understanding of its accuracy and limitations in detecting individual CaP foci to optimize management.Objective
To determine the per-lesion detection rate for CaP foci by mpMRI and identify predictors of tumor detection.Design, setting, and participants
We carried out a retrospective analysis of a prospectively managed database correlating lesion-specific results from mpMRI co-registered with whole-mount pathology (WMP) prostatectomy specimens from June 2010 to February 2018. Participants include 588 consecutive patients with biopsy-proven CaP undergoing 3-T mpMRI before radical prostatectomy at a single tertiary institution.Outcome measurements and statistical analysis
We measured mpMRI sensitivity in detecting individual CaP and clinically significant (any Gleason score ≥7) CaP foci and predictors of tumor detection using multivariate analysis.Results and limitations
The final analysis included 1213 pathologically confirmed tumor foci in 588 patients with primarily intermediate- (75%) or high-risk (12%) CaP. mpMRI detected 45% of all lesions (95% confidence interval [CI] 42–47%), including 65% of clinically significant lesions (95% CI 61–69%) and nearly 80% of high-grade tumors. Some 74% and 31% of missed solitary and multifocal tumors, respectively, were clinically significant. The majority of missed lesions were small (61.1% ≤1 cm); 28.3% were between 1 and 2 cm, and 10.4% were >2 cm. mpMRI missed at least one clinically significant focus in 34% of patients overall, and in 45% of men with multifocal lesions. On multivariate analysis, smaller, low-grade, multifocal, nonindex tumors with lower prostate-specific antigen density were more likely to be missed. Limitations include selection bias in a prostatectomy cohort, lack of specificity data, an imperfect co-registration process, and uncertain clinical significance for undetected lesions.Conclusions
mpMRI detects less than half of all and less than two-thirds of clinically significant CaP foci. The moderate per-lesion sensitivity and significant proportion of men with undetected tumor foci demonstrate the current limitations of mpMRI.Patient summary
Magnetic resonance imaging of the prostate before surgical removal for prostate cancer finds less than half of all individual prostate cancer tumors. Large, solitary, aggressive tumors are more likely to be visualized on imaging. 相似文献36.
Kimberly A. Parker Bobi Ivanov Allison Thieneman Kevin Wombacher Tara Watterson Molly Burchett 《Journal of substance use》2019,24(2):147-149
Background and Objective: Although preventable, substance addiction has become one of the most prominent public health problems facing the nation. As a result, treatment programs and centers have focused resources and efforts on aiding individuals on their path to long-term recovery. However, the constant threat, reinforced by high incidence, of relapse presents a major obstacle to long-term recovery. Relapse prevention programs are designed to target social and psychological factors contributing to lapses in sobriety. Yet, the exact factors that can impact long-term recovery and prevent or lower the instances of relapse are not always clear. The current study explores the major contributors to relapse as experienced in a male residential treatment center.
Methods: The data were gathered through 31 in-depth interviews in a residential halfway house treatment facility for substance use recovery.
Results: The results of the study underscored social support and interpersonal relationships as major factors impacting long-term recovery. More specifically, lack of efficacy in managing interpersonal relationships and building new support networks were identified as essential barriers to long-term recovery.
Conclusions: The management of interpersonal relationships seems to be a key to long-term recovery, which emphasizes the need for strategies that underscore the development of positive relationships that will strengthen resistance to relapse and long-term recovery. 相似文献
37.
Maryam Boumezrag Sormeh Harounzadeh Hamza Ijaz Angeline Johny Lorna Richards Yan Ma Maxine A. Le Saux Paige Kulie Caitlin Davis Andrew C. Meltzer 《The American journal of emergency medicine》2019,37(2):304-307
Study objectives
The primary objective of this study was to compare Emergency Department patients with first-time versus recurrent acute pancreatitis.Methods
This study was a retrospective chart review of patients with a diagnosis of acute pancreatitis who presented to a single academic urban emergency department from 2012 to 2016. Criteria for inclusion were clinical symptoms of pancreatitis, age greater than or equal to 18?years, ED diagnosis of acute pancreatitis, and an abdominal CT scan within 24?h of triage. Exclusion criteria were traumatic mechanism and pregnancy. Charts were reviewed by a minimum of two trained abstractors using structured data collection sheets and discrepancies were resolved by a third abstractor. Patients with first time acute pancreatitis versus recurrent acute pancreatitis were compared to determine differences in characteristics, management and disposition.Results
250 patients were included in the study. Of these, 165 patients had first-time acute pancreatitis and 85 patients had recurrent acute pancreatitis. Demographics, vital signs and initial lab values were the same in both groups. Patients with recurrent acute pancreatitis were more likely to have significant findings on CT (Modified CT Severity Index, 2.09 versus 1.43, p?<?0.05), more likely to require IV opiates (96% versus 75%, p?<?0.001) and less likely to need ICU admission (8% versus 19%, p?=?0.03).Conclusion
ED patients with recurrent acute pancreatitis demonstrated more significant findings on CT compared to patients with first-time acute pancreatitis but were less likely to require ICU admission. 相似文献38.
Sevan Komshian Alik Farber Virendra I. Patel Philip P. Goodney Marc L. Schermerhorn Elizabeth A. Blazick Douglas W. Jones Denis Rybin Gheorghe Doros Jeffrey J. Siracuse 《Journal of vascular surgery》2019,69(2):405-413
Objective
Although endovascular repair of abdominal aortic aneurysms (AAAs) has been demonstrated to have favorable outcomes, not all cohorts of patients with AAA fare equally well. Our goal was to investigate perioperative and 1-year outcomes in patients with end-stage renal disease (ESRD) on dialysis, who have traditionally fared worse after vascular interventions, to assess how ESRD affects outcomes in a large modern cohort of endovascular aneurysm repair (EVAR) patients.Methods
The Vascular Quality Initiative database was queried for all patients undergoing EVAR from 2010 to 2017. ESRD patients were compared with patients not on dialysis. Propensity-matched scoring and multivariable analysis were used to isolate the effects of ESRD.Results
Of 28,683 EVARs identified, there were 321 (1.12%) patients with ESRD on dialysis. Patients with ESRD had no difference in presenting AAA size (57.5 ± 12.7 mm vs 56.7 ± 17.2 mm; P = .44); however, they had more urgent/emergent repairs (20.6% vs 13.6%; P = .002) than those without ESRD. ESRD patients were more often younger, nonwhite, and nonobese and less likely to have commercial insurance (P < .05). ESRD patients more often had hypertension, coronary artery disease, congestive heart failure, previous lower extremity bypass, aneurysm repair, and carotid interventions (P < .05). There was no difference in the rate of concomitant procedures. Matching based on demographics, comorbidities, and operative details showed that ESRD patients had longer hospital length of stay (4.8 ± 9.4 days vs 4.1 ± 12.6 days; P = .026) and higher 30-day mortality (7% vs 2.4%; P < .001). There was no difference in cardiac, pulmonary, lower extremity, bowel, and stroke complications or return to the operating room. On multivariable analysis, ESRD was associated with 30-day mortality (odds ratio, 4.1; 95% confidence interval, 2.6-6.7; P < .001). Of the 24,750 elective EVARs, 1.04% had ESRD on dialysis. Matched data for elective EVAR show increased postoperative length of stay, hospital mortality, and 30-day mortality for ESRD patients on dialysis compared with those who are not. There was no association with postoperative myocardial infarction or pulmonary complications. At 1 year, patients with ESRD on dialysis had worse survival (78% vs 94%; P < .001), and ESRD was associated with higher mortality (hazard ratio, 3.3; 95% confidence interval, 2.5-4.2; P < .001).Conclusions
Among patients undergoing EVAR, ESRD is independently associated with higher perioperative and 1-year mortality despite not being associated with higher postoperative complications. This should be taken into account during informed consent for EVAR and risk-benefit considerations in this high-risk population, particularly for elective repair. 相似文献39.
Anthony J. Bleyer Vincent A. Scavo Samuel E. Wilson Barry J. Browne Brian L. Ferris C. Keith Ozaki Timmy Lee Eric K. Peden Bradley S. Dixon Rick Mishler Timothy P. O&#x;Connor Kendrah Kidd Steven K. Burke 《Journal of vascular surgery》2019,69(2):507-515
Objective
Arteriovenous fistulas created in patients with chronic kidney disease often lose patency and fail to become usable. This prospective trial evaluated the efficacy of vonapanitase, a recombinant human elastase, in promoting radiocephalic fistula patency and use for hemodialysis.Methods
PATENCY-1 was a double-blind, placebo-controlled trial that enrolled 349 patients on or approaching hemodialysis and being evaluated for radiocephalic arteriovenous fistula creation. Of these, 313 were randomized and 311 treated. Patients were assigned to vonapanitase (n = 210) or placebo (n = 103). The study drug solution was applied topically to the artery and vein for 10 minutes immediately after fistula creation. The primary and secondary end points were primary patency (time to first thrombosis or corrective procedure) and secondary patency (time to abandonment). Tertiary end points included use of the fistula for hemodialysis, fistula maturation by ultrasound, and procedure rates.Results
The Kaplan-Meier estimates of 12-month primary patency were 42% (95% confidence interval [CI], 35-49) and 31% (95% CI, 21-42) for vonapanitase and placebo (P = .25). The Kaplan-Meier estimates of 12-month secondary patency were 74% (95% CI, 68-80) and 61% (95% CI, 51-71) for vonapanitase and placebo (P = .048). The proportions of vonapanitase and placebo patients were 39% and 25% (P = .035) with unassisted use for hemodialysis and 64% and 44% (P = .006) with unassisted plus assisted use.Conclusions
Vonapanitase treatment did not significantly improve primary patency but was associated with increased secondary patency and use for hemodialysis. Further research is needed to evaluate these end points. 相似文献40.
S. Kim M.J. Graham R.G. Lee L. Yang S. Kim V. Subramanian J.D. Layne L. Cai R.E. Temel D. Shih A.J. Lusis J.A. Berliner S. Lee 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2019,29(3):306-315