Tag: statistics

J Neurotrauma. 2023 Apr 26. doi: 10.1089/neu.2022.0419. Online ahead of print.

ABSTRACT

Hyperventilation (HV) therapy uses vasoconstriction to reduce intracranial pressure (ICP) by reducing cerebral blood volume. However, as HV also lowers cerebral blood flow (CBF), it may provoke misery perfusion (MP) where the decrease in CBF is coupled with increased oxygen extraction fraction (OEF). MP may rapidly lead to the exhaustion of brain energy metabolites, making it vulnerable to ischemia. MP is difficult to detect at the bedside, which is where transcranial hybrid, near-infrared spectroscopies are promising since they noninvasively measure OEF and CBF. We have tested this technology during HV (∼30 minutes) with bilateral, frontal lobe monitoring to assess MP in twenty-seven sessions in eighteen patients with traumatic brain injury. In this study, HV did not lead to MP at a group level (p>0.05). However, a statistical approach yielded eighty-nine events with a high probability of MP in nineteen sessions. We have characterized each statistically significant event in detail and their possible relation with clinical and radiological status (decompressive craniectomy and presence of a cerebral lesion), without detecting any statistically significant difference (p>0.05). However, MP detection stresses the need for personalized, real-time assessment in future clinical trials with HV, in order to provide an optimal evaluation of the risk-benefit balance of HV. Our study provides pilot data demonstrating that bedside transcranial hybrid near-infrared spectroscopies could be utilized to assess potential MP.

PMID:37125452 | DOI:10.1089/neu.2022.0419

J Neurotrauma. 2023 Apr 26. doi: 10.1089/neu.2022.0507. Online ahead of print.

ABSTRACT

Data supporting the benefits of early surgical intervention in acute spinal cord injury (SCI) is growing. For early surgery to be accomplished, understanding the causes of variabilities that effect the timing of surgery is needed to achieve this goal. The purpose of this analysis is to determine factors that affect the timing of surgery for acute cervical SCI within the North American Clinical Trials Network (NACTN) for SCI registry. Patients in the NACTN SCI registry from 2005 to 2019 with a cervical SCI, excluding Acute Traumatic Central Cord Syndrome, were analyzed for time elapsed from injury to arrival to the hospital, and time to surgery. Two categories were defined: 1) Early Arrival with Early Surgery commenced within 24 hours of injury (EAES) and 2) Early Arrival but Delayed Surgery (EADS) with surgery occurring between 24 to 72 hours post-injury. Patients’ demographic features, initial clinical evaluation, medical comorbidities, neurological status, surgical intervention, complications, and outcome data were correlated with respect to the two arrival groups. Of the 222 acute cervical SCI patients undergoing surgery, 163 (73.4%) were EAES, and 59 (26.6%) were EADS. There was no statistical difference in arrival time between the EAES and EADS groups. There was a statistical difference in the median arrival time to surgery between the EAES group (9 hours) compared to the EADS group (31 hours) (p<0.05). There was no statistical difference in race, sex, age, mechanism of injury, APACHE II scores, or medical comorbidities between the two groups but the EAES group did present with a significantly lower systolic blood pressure (p<0.05). EADS patients were more likely to present as an AIS D than EAES (p<0.05). Early surgery was statistically more likely to occur if the injury occurred over the weekend (p<0.05). There were variations in the rates of early surgery between the 8 NACTN sites within the study, ranging from 57% to 100%. Of the 114 patients with 6-month outcome data, there was no significant change between the two groups regarding AIS grade change and motor/pin prick/light touch score recovery. A trend towards improved motor scores with early surgery was not statistically significant (p=0.21). Although there is data that surgery within 24 hours of injury improves outcomes and can be performed safely, there remain variations in care outside of clinical trials. In the present study of cervical SCI, NACTN achieved its goal of early surgery in 73.4% of patients from 2005-2019 who arrived within 24 hours of their injury. Variability in achieving this goal was related to severity of neurological injury, the day of the week, and the treating NACTN center. Evaluating variations within our network improves understanding of potential systemic limitations and our decision-making process to accomplish the goal of early surgery.

PMID:37125447 | DOI:10.1089/neu.2022.0507

Dent Mater J. 2023 Apr 28. doi: 10.4012/dmj.2022-273. Online ahead of print.

ABSTRACT

This study investigated the effect of 10-methacryloyloxydecyl dihydrogen phosphate (MDP) in methyl methacrylate (MMA) monomer on the adhesion of tri-n-butylborane (TBB)-initiated resins (MDP/MMA-TBB resins) to human enamel. Enamel surface conditions were either polished only or phosphatized surfaces. The 1.0, 1.7, and 2.0 mol% MDP/MMA-TBB resins, 4-methacryloxyethyl trimellitate anhydride (4-META)/MMA-TBB resin and MMA-TBB resin were prepared as luting materials. The shear bond strength was determined before and after thermocycles, and the results were compared using non-parametric statistical analyses (each, n=15). The MDP/MMA-TBB resins showed significantly better bond durability to enamel than other resins with or without etching. The 1.7 and 2.0 mol% MDP/MMA-TBB resins were suggested to be the optimum MDP concentrations from pre- and post-thermocycling results for the non-etched specimens. The TBB initiator resin including MDP was shown to be effective in bonding to human enamel, and this effect was enhanced in combination with phosphate treatment.

PMID:37121735 | DOI:10.4012/dmj.2022-273

J Clin Exp Hematop. 2023 Apr 28. doi: 10.3960/jslrt.23001. Online ahead of print.

ABSTRACT

We retrospectively evaluated long-term outcomes of high dose chemotherapy followed by autologous stem cell transplant (HDC/ASCT) in patients with diffuse large B-cell lymphoma (DLBCL). Between 2004 and 2020, 46 DLBCL patients received HDC/ASCT in our institution, including 12 patients (26.1%), who received as an upfront setting (UFS). At a median follow-up time of 69 months (range, 2-169 months), the 5-year progression-free survival (PFS) rates were 82.5% (95%CI, 46.1-95.3%) in the UFS, and 57.8% (95%CI, 38.1-73.2%) in the relapsed or refractory (R/R) patients (n=34), respectively. The 5-year PFS rates were 62.3% (95%CI, 34.0-81.3%) in primary resistant (n=13) or early relapsing (within 1 year from the initial diagnosis) patients (n=4), and 53.3% (95%CI, 25.9-74.6%) in those relapsing >1 year after the initial diagnosis (n=17), with no statistically significant difference (p=0.498). In R/R patients, multivariate analysis showed that the remission status before HDC/ASCT was an independent poor prognostic factor for progression-free survival (hazard ratio [HR], 17.0; 95%CI, 3.35-86.6; p=0.000630) and high-risk category in the international prognostic index for OS (HR, 9.39; 95%CI, 1.71-51.6; p=0.0100). The incidence of non-relapse mortality by 5 years, and 10 years were 12.2%, and 15.2%, respectively. Eleven patients (23.9%) developed second malignancies, which was the most frequent late complication after HDC/ASCT, with 5-year, and 10-year cumulative incidence of 16.9%, 22.5%, respectively. In conclusion, HDC/ASCT is effective for chemo-sensitive R/R DLBCL regardless of the timing and lines of therapy. However, careful observation is required, considering the long-term complications such as secondary malignancies.

PMID:37121716 | DOI:10.3960/jslrt.23001

J Wound Care. 2023 May 1;32(Sup5):S6-S10. doi: 10.12968/jowc.2023.32.Sup5.S6.

ABSTRACT

OBJECTIVE: The objective of the current study was to evaluate outcomes of elective knee arthroscopy portal closure comparing two skin closure techniques.

METHOD: This was a randomised controlled trial including healthy volunteers aged ≥18 years undergoing elective knee arthroscopy that used two portals. At the time of surgery, each patient’s two arthroscopy portal closures were randomised to one of two closure techniques; the first technique used approximation of the skin with a micro-anchor skin dressing (BandGrip Inc., US), while the second closure technique used an absorbable suture (Biosyn Monofilament, Medtronic) and a liquid bonding agent skin closure (Dermabond, Ethicon Inc., US). Postoperative complications and patient-reported outcomes were evaluated at the first visit after knee arthroscopy and at six weeks postoperatively.

RESULTS: A total of 38 patients (76 portals) were enrolled in this study. No patients reported wound complications of either portal; thus, there was no significant difference (p>0.05) in wound complication rates between the skin closure techniques. Survey questions regarding any difference in appearance and cosmesis between the closure techniques’ portal sites were responded to by 15 patients, all of whom indicated no difference in appearance between the portal sites. There was also no statistically significant difference between the two closure techniques with regards to appearance.

CONCLUSION: There was no significant difference in presence of wound complications or appearance between skin closure with the micro-anchor skin dressing and the absorbable suture/liquid bonding agent skin closure.

PMID:37121665 | DOI:10.12968/jowc.2023.32.Sup5.S6

J Prosthet Dent. 2023 May;129(5):797.e1-797.e7. doi: 10.1016/j.prosdent.2023.03.017.

ABSTRACT

STATEMENT OF PROBLEM: Studies comparing the physicomechanical characteristics of denture base resins manufactured by computer-aided design and computer-aided manufacturing (CAD-CAM) milling and 3-dimensional (3D) printing are sparse, resulting in challenges when choosing a fabrication method for complete dentures.

PURPOSE: The purpose of this in vitro study was to evaluate and compare the impact strength, flexural strength, and the surface roughness of denture base resins manufactured by CAD-CAM milling and 3D printing before and after thermocycling and polishing.

MATERIAL AND METHODS: Evaluation of the physicomechanical properties (n=35) was completed before and after 500 thermocycles. Impact strength (n=14) was measured with a Charpy impact tester and flexural strength (n=14) with the 3-point bend test. Surface roughness (Ra) was evaluated (n=7) with a profilometer before and after thermocycling and polishing and by viewing the surface topography before and after polishing using a scanning electron microscope at ×2000. The Mann-Whitney U test and Wilcoxon sign rank test were used for statistical analysis (α=.05).

RESULTS: Milled specimens showed statistically significantly higher impact strength before thermocycling and statistically significantly higher flexural strength before and after thermocycling (P=.004) compared with 3D-printed specimens. The Ra values for the milled group were significantly lower than for the 3D-printed group both before and after thermocycling (P=.006) and after polishing (P=.027). Thermocycling resulted in a statistically significant difference in flexural strength (P=.018) in both groups and in surface roughness in the milled group (P=.048); but no significant effect was found on impact strength (P>.05). Ra values for the 3D-printed group decreased after polishing (P=.048).

CONCLUSIONS: Milled specimens had higher flexural and impact strength and lower surface roughness values than 3D-printed specimens. Polishing significantly reduced the surface roughness in 3D-printed specimens but had no significant effect on milled specimens.

PMID:37121625 | DOI:10.1016/j.prosdent.2023.03.017

J Prosthet Dent. 2023 May;129(5):796.e1-796.e7. doi: 10.1016/j.prosdent.2023.03.016.

ABSTRACT

STATEMENT OF PROBLEM: Novel 3-dimensionally printed resin and milled polymethyl methacrylate materials have been marketed for computer-aided design and computer-aided manufacturing (CAD-CAM) denture base fabrication. However, information on the flexural strength of digitally fabricated denture base material is limited, and little is known about how they are affected by a hard-reline procedure.

PURPOSE: The purpose of this in vitro study was to assess the flexural strength of 6 digitally manufactured denture base materials and to assess the effect of a hard-reline procedure on their flexural strength.

MATERIAL AND METHODS: A total of 140 strips of denture base material were fabricated from a conventional heat-polymerized polymethyl methacrylate (L199), 3 brands of milled polymethyl methacrylate (IBC, DSL, and ADH), and 3 brands of 3D-printed resin (DFD, ADB, and DrFD) (n=20). Ten specimens in each group did not receive any treatment, and 10 were relined with a hard-reline material (ProBase Cold Trial Kit). Specimens were then subjected to a 3-point flexural strength test using a universal testing machine at a crosshead speed of 5.0 mm/min. A 1-way ANOVA test followed by the Tukey multiple comparison test was used to detect the difference in flexural strength and the strain at fracture of the different types of denture base materials (α=.05). The comparison of flexural strength between with and without hard-reline was analyzed using an unpaired t test (α=.05).

RESULTS: All materials, with or without the hard-reline, met the International Organization for Standardization (ISO) 20 795-1:2013 standard for flexural strength (65 MPa). The milled materials (DSL>IBC≈ADH) showed higher flexural strength than the 3D-printed or conventional materials (DrFD>DFD≈ADB≈L199) without a hard-reline. No statistical difference in flexural strength was found among the hard-relined denture base materials (P=.164). All 3 milled materials showed reduced flexural strength after relining, while the relined conventional (L199) and 3D-printed materials (DFD and ADB) showed notably higher flexural strength; printed DrFD showed no significant difference (P=.066). In terms of strain at fracture, the milled materials displayed higher values than those of the conventional or 3D-printed materials (P<.05).

CONCLUSIONS: All digitally fabricated denture base materials were within acceptable limits for clinical use, even after hard relining. Flexural strength was highly dependent on the type of material. Hard relining affected the flexural strength of most of the digitally fabricated denture base materials.

PMID:37121624 | DOI:10.1016/j.prosdent.2023.03.016

Int J Hyperthermia. 2023;40(1):2200582. doi: 10.1080/02656736.2023.2200582.

ABSTRACT

The purpose of the study is to retrospectively evaluate the development and technological progress in local oncological treatments of patients with breast cancer liver metastasis (BCLM) using LITT (laser interstitial thermotherapy), MWA (microwave ablation) and TACE (transarterial chemoembolization) ablation techniques in a multimodal application. The study uses data generated between 1993 and 2020. Therapy results were evaluated using the Kaplan-Meier survival estimate, Cox proportional hazard regression and log-rank test. Cox regression analysis showed that the different treatment methods are statistically significant predictors of survival of patients. Median survival times for groups treated with LITT (212 patients) and LITT + TACE (215 patients) were 2.2 years and 2.1 years respectively; median survival times for groups treated with MWA (17 patients) and MWA + TACE (143 patients) were 5.6 and 2.4 years respectively. For LITT only treatments, the 1-, 3- and 5-year survival probability scored 80%, 37%, 22%. Results for combined LITT + TACE treatments were 76%, 34% and 15%. In group MWA, the 1-/3-/5-year survival probability rates were calculated as 89%, 89%, 89% (however, they should be interpreted carefully due to a relatively small sample size of n = 17 patients). Group MWA + TACE offered values of 77%, 38% and 22%. A separate group of 549 patients was analyzed with TACE monotherapy treatment. The estimated median survival time in this group was 0.8 years. The 1-/3-/5-year survival probability rates were 37%, 8% and 4%. Treatments with combined MWA and MWA + TACE resulted in the best median survival time estimations in this study.

PMID:37121606 | DOI:10.1080/02656736.2023.2200582

Fertil Steril. 2023 Apr 28:S0015-0282(23)00316-3. doi: 10.1016/j.fertnstert.2023.04.031. Online ahead of print.

ABSTRACT

Uncertainty is a common element when designing a study and assumptions made around this uncertainty inform the statistical analysis to be performed. Sensitivity analyses provide confidence in the primary analytic results obtained from the study by probing at the assumptions and uncertainty. Researchers are strongly encouraged to consider sensitivity analyses during the design phase of the study and include them in the manuscript to increase confidence in the conclusions.

PMID:37121566 | DOI:10.1016/j.fertnstert.2023.04.031

Clin Gastroenterol Hepatol. 2023 Apr 28:S1542-3565(23)00317-8. doi: 10.1016/j.cgh.2023.04.017. Online ahead of print.

ABSTRACT

BACKGROUND & AIMS: Little is known about the potential impact of statins on progression of non-cirrhotic chronic liver diseases (CLD) to severe liver disease.

METHODS: Using liver histopathology data in a nationwide Swedish cohort, we identified 3,862 non-cirrhotic individuals with CLD and statin exposure, defined as a statin prescription filled for ≥30 cumulative defined daily doses. Statin users were matched to 3,862 (statin) non-users with CLD through direct 1:1 matching followed by propensity score matching. Cox regression was used to estimate hazard ratios (HRs) for the primary outcome of incident severe liver disease (a composite of cirrhosis, hepatocellular carcinoma (HCC), and liver transplantation/liver-related mortality).

RESULTS: 45.3% of CLD patients had non-alcoholic fatty liver disease (NAFLD), 21.9% alcohol-related liver disease (ALD), 17.7% viral hepatitis and 15.1% autoimmune hepatitis (AIH). During follow-up, 234 (6.1%) of statin users vs. 276 (7.1%) of non-users developed severe liver disease. Statin use was associated with a decreased risk of developing severe liver disease (HR=0.60; 95%CI=0.48-0.74). Statistically significantly lower rates of severe liver disease were seen in ALD (HR=0.30; 0.19-0.49) and NAFLD (HR=0.68; 0.45-1.00), but not in viral hepatitis (HR=0.76; 0.51-1.14) or AIH (HR=0.88; 0.48-1.58). Statin use had a protective association in both pre-fibrosis and fibrosis stages at diagnosis. Statin use was associated with lower rates of progression to cirrhosis (HR=0.62; 0.49-0.78), HCC (HR=0.44; 0.27-0.71), and liver-related mortality (HR=0.55; 0.36-0.82).

CONCLUSIONS: Among individuals with non-cirrhotic CLD, incident statin use was linked to lower rates of severe liver disease suggesting a potential disease modifying role.

PMID:37121528 | DOI:10.1016/j.cgh.2023.04.017