Tag: pubmed

Phys Med Biol. 2021 Aug 5. doi: 10.1088/1361-6560/ac1b1b. Online ahead of print.

ABSTRACT

Iterative reconstruction framework shows predominance in low dose and incomplete data situation. In the iterative reconstruction framework, there are two components, i.e., fidelity term aims to maintain the structure details of the reconstructed object, and the regularization term uses prior information to suppress the artifacts such as noise. A regularization parameter balances them, aiming to find a good trade-off between noise and resolution. Currently, the regularization parameters are selected as a rule of thumb or some prior knowledge assumption is required, which limits practical uses. Furthermore, the computation cost of regularization parameter selection is also heavy. In this paper, we address this problem by introducing CT image quality assessment (IQA) into the iterative reconstruction framework. Several steps are involved during the study. First, we analyze the CT image statistics using the dual dictionary method. Regularities are observed and concluded, revealing the relationship among the regularization parameter, iterations, and CT image quality. Second, with derivation and simplification of DDL procedure, a CT IQA metric named SODVAC is designed. The SODVAC locates the optimal regularization parameter that results in the reconstructed image with distinct structures and with no noise or little noise. Third, we introduce SODVAC into the iterative reconstruction framework and then propose a general image-quality-guided iterative reconstruction (QIR) framework and give a specific framework example (sQIR) by introducing SODVAC into the iterative reconstruction framework. sQIR simultaneously optimizes the reconstructed image and the regularization parameter during the iterations. Results confirm the effectiveness of the proposed method. No prior information needed and low computation cost are the advantages of our method compared with existing state-of-theart L-curve and ZIP selection strategies.

PMID:34352735 | DOI:10.1088/1361-6560/ac1b1b

Respiration. 2021 Aug 5:1-9. doi: 10.1159/000517527. Online ahead of print.

ABSTRACT

BACKGROUND: Current guidelines for the treatment of noncystic fibrosis bronchiectasis (NCFB) recommend pulmonary rehabilitation (PR), but to date, there are few studies that have proven its effectiveness.

OBJECTIVE: The main objective of this study was to examine the effect of PR on pulmonary function tests and exercise capacity.

METHOD: The aim of this study was to systematically review the effects of PR in NCFB on (1) forced expiratory volume in the first second (FEV1) and (2) exercise capacity evaluated by the 6-min walk test (6MWT) and the incremental shuttle walk test (ISWT). This meta-analysis was undertaken according to PRISMA recommendations.

RESULTS: This pair-wise meta-analysis included data obtained from studies that enrolled 529 NCFB patients. The FEV1 assessment after PR between the active and control group did not show any significant increase (FEV1 difference 0.084 mL; CI: -0.064, +0.233; p = 0.264), and there was an increasing trend (188 mL; CI: -0 to 0.009, +0.384) at the limits of statistical significance (p = 0.061). Walked distance showed a significant increase in the PR group compared to the control group (ISWT distance difference 070.0 m; CI: 55.2, 84.8; p < 0.001), and this finding was confirmed before and after PR both by the ISWT (68.85 m greater than baseline; CI: 40.52, 97.18; p < 0.001) and by the 6MWT (37.7 m greater than baseline; CI: 20.22, 55.25; p < 0.001).

CONCLUSIONS: PR improves exercise tolerance in NCFB patients, but it has a modest impact on respiratory function.

PMID:34352795 | DOI:10.1159/000517527

ESMO Open. 2021 Aug 2;6(4):100222. doi: 10.1016/j.esmoop.2021.100222. Online ahead of print.

ABSTRACT

BACKGROUND: Despite its proven activity as third-line treatment in gastrointestinal stromal tumors (GIST), regorafenib can present a poor tolerability profile which often leads to treatment modifications and transient or permanent discontinuation; thus, in clinical practice physicians usually adopt various dosing and interval schedules to counteract regorafenib-related adverse events and avoid treatment interruption. The aim of this real-world study was to investigate the efficacy and safety of personalized schedules of regorafenib in patients with metastatic GIST, in comparison with the standard schedule (160 mg daily, 3-weeks-on, 1-week-off).

PATIENTS AND METHODS: Institutional registries across seven Italian reference centers were retrospectively reviewed and data of interest retrieved to identify patients with GIST who had received regorafenib from February 2013 to January 2021. The Kaplan-Meier method was used to estimate survival and the log-rank test to make comparisons.

RESULTS: Of a total of 152 patients with GIST, 49 were treated with standard dose, while 103 received personalized schedules. At a median follow-up of 36.5 months, median progression-free survival was 5.6 months [95% confidence interval (CI) 3.73-11.0 months] versus 9.7 months (95% CI 7.9-14.5 months) in the standard-dose and the personalized schedule groups, respectively [hazard ratio (HR) 0.51; 95% CI 0.34-0.75; P = 0.00052]. Median overall survival was 16.6 months (95% CI 14.1-21.8 months) versus 20.5 months (95% CI 15.0-25.4 months), respectively (HR 0.75; 95% CI 0.49-1.22; P = 0.16).

CONCLUSIONS: Regorafenib-personalized schedules are commonly adopted in daily clinical practice of high-volume GIST expert centers and correlate with significant improvement of therapeutic outcomes. Therefore, regorafenib treatment optimization in patients with GIST may represent the best strategy to maximize long-term therapy.

PMID:34352702 | DOI:10.1016/j.esmoop.2021.100222

Drug Metab Pharmacokinet. 2021 May 29;40:100407. doi: 10.1016/j.dmpk.2021.100407. Online ahead of print.

ABSTRACT

We evaluated the impact of vonoprazan on blood concentrations of tacrolimus via a retrospective analysis of 52 renal transplant recipients who took tacrolimus and converted from rabeprazole to vonoprazan between August 2018 and September 2019. We compared tacrolimus trough levels upon conversion among groups that were classified based on cytochrome P450 (CYP) gene polymorphisms. CYP3A5 groups were heterozygous or homozygous for CYP3A5∗1 and CYP3A5∗3 alleles. CYP2C19 genotypes were classified as extensive (∗1/∗1), intermediate (∗1/∗2 and ∗1/∗3) or poor metabolizers (∗2/∗2, ∗2/∗3 and ∗3/∗3). Tacrolimus trough levels increased only 0.3 ng/mL upon conversion in the CYP3A5∗3/∗3 group: 5.8 [3.4-7.2] vs 6.1 [3.8-7.9]; p = 0.06. No statistically significance changes in tacrolimus levels also occurred in the CYP3A5∗1/∗1 or CYP3A5∗1/∗3 groups. Subgroup analyses of CYP3A5∗3/∗3 demonstrated low changes for all three CYP2C19 subgroups: 5.2 [4.3-6.5] vs 6.2 [4.3-7.9]; p = 0.07, 6.1 [3.4-7.2] vs 6.7 [4.6-7.9]; p = 0.12 and 5.4 [3.6-6.5] vs 4.7 [3.8-6.3]; p = 1.00, respectively. Conversion to vonoprazan thus resulted in little increase of tacrolimus trough levels, even in the group predicted to be most susceptible (CYP3A5∗3/∗3 and 2C19∗1/∗1), thus supporting the safety of concomitant use of vonoprazan with tacrolimus.

PMID:34352707 | DOI:10.1016/j.dmpk.2021.100407

Food Chem. 2021 Jul 23;367:130679. doi: 10.1016/j.foodchem.2021.130679. Online ahead of print.

ABSTRACT

The chemical complexity of coffee influences the sensory evaluation of the beverage, the main method used to define the quality of the coffee. In view of the subjectivity that method offers, we propose the association of an instrumental method with multivariate calibration (PLS and GA-SVR) to predict the quality of arabica coffee as support for sensory analysis. Arabica coffee samples were submitted to sensory evaluation using the Specialty Coffee Association (SCA) protocol and HS-SPME-GC/MS analysis. The models presented RMSEp results from 0.20 to 0.25, within the evaluation range the quality levels of sensory attributes (0.25). For the fragrance/aroma attribute, a value of R²p equal to 0.8503 was reached. 15 volatile compounds were identified as responsible for predicting the quality of arabica coffee, among which, 1-nonadecene was first reported as an impact compound in the prediction of important sensory attributes.

PMID:34352695 | DOI:10.1016/j.foodchem.2021.130679

Clin Oral Implants Res. 2021 Aug 5. doi: 10.1111/clr.13815. Online ahead of print.

ABSTRACT

OBJECTIVES: The present pilot study analyzed two abutment types (a retentive ball and a non-retentive dome) in implant-assisted removable partial dentures (IARPDs) on 6 mm short implants with respect to clinical, radiological, and patient-reported outcomes (PROs), during the first year.

MATERIALS AND METHODS: Two implants were placed bilaterally in mandibular molar sites, converting existing free-end removable partial dentures (RPDs) to IARPDs. Twelve subjects were randomized to initially receive either the dome (Group A, n=6) or the ball abutment (Group B, n=6). After eight weeks, the abutments were exchanged. After another 8 weeks, the participants were given the choice of one of the abutments. Mean values and standard deviations (sd) were calculated, and random-effect linear regression analyses were applied to analyze marginal bone level alterations and PROs (α < 0.05).

RESULTS: Twelve participants were included in the study; however, one drop-out occurred. Patient ratings increased significantly in both study groups. The majority of the participants (82%) ultimately chose the ball abutment. The implant survival rate was 100%, and the success rate was 90.9% twelve months after implant placement (mean peri-implant bone-loss: -1.2; sd: 0.6mm) without a statistically significant difference between the study groups, in terms of clinical- and radiological outcomes.

CONCLUSION: Placing 6 mm short implants at mandibular molar sites of RPD wearers seems to be a viable treatment option, based on this investigation with a short-term follow-up. Although only minor differences between the two abutments were observed, patients seem to prefer the ball over the dome abutment.

PMID:34352145 | DOI:10.1111/clr.13815

J Cosmet Dermatol. 2021 Aug 5. doi: 10.1111/jocd.14360. Online ahead of print.

ABSTRACT

BACKGROUND: Enlarged facial pores are a common cosmetic complaint in practice. Microfocused ultrasound with visualization (MFU-V) and low-degree crosslinked hyaluronic acid filler (L-HA) injection has recently become a popular procedure for skin rejuvenation. The effectiveness of the combined MFU-V and L-HA injection in the treatment of enlarged pores has not been evaluated.

OBJECTIVES: To compare the efficacy of MFU-V monotherapy (single technique) and MFU-V combined with L-HA injection (combined technique) for the treatment of enlarged facial pores in Asians.

METHODS: We conducted a randomized, single-blinded, split-face study on participants with enlarged facial pores. Each side of the face was randomly assigned to treatment with one session of single technique or combined technique. Pore volume was objectively measured by an Antera 3D^® system. Subjective assessment was evaluated by one-blinded physician using a pore grading score (0-4). Patients rated the improvement in terms of satisfaction using the visual analog scale (VAS, 0-10).

RESULTS: Forty-six participants completed the study. The mean pore volume of both sides declined with statistical significance at every visit compared to baseline, with the lowest mean at 4 months post-treatment. The combined technique showed a lower mean pore volume than single technique throughout the follow-ups. Physician’s subjective evaluation showed no statistically significant difference between the two techniques. The patient satisfaction score showed a similar trend to the mean pore volume, with a statistically significant difference at 4 and 6 months post-treatment.

CONCLUSIONS: Both techniques are effectively minimize enlarged facial pores. The combined technique resulted in more patient satisfaction.

PMID:34352146 | DOI:10.1111/jocd.14360

Clin Oral Implants Res. 2021 Aug 5. doi: 10.1111/clr.13812. Online ahead of print.

ABSTRACT

OBJECTIVES: Evaluate the dimensions and morphology of peri-implant tissues around a modified dental implant designed with tissue level connection and a convergent transmucosal neck, when compared with a conventional bone level implant connected to a cylindrical machined titanium abutment.

MATERIAL AND METHODS: Eight experimental animals were used for this in vivo investigation, in whom 16 test and 16 control implants were placed following a random allocation sequence. The following histological outcomes at 4 and 12 weeks were evaluated: morphology of peri-implant tissues, the soft tissue height and thickness, the horizontal and vertical bone remodeling and the bone to implant contact (BIC).

RESULTS: In both early (4 weeks) and late (12 weeks) healing times, there were no statistically significant differences between test and control implants, with respect to the overall height and thickness of the peri-implant hard and soft tissues. There was a tendency towards a more coronal free gingival margin (I-FGM) at the buccal aspect of test when compared to control implants (at 4 weeks, difference of 0.97mm (p=0.572) and 0.30mm (p=1.000) at 12 weeks). Similarly, there was a tendency towards a more coronal position of the first bone to implant contact (I-B) at the buccal aspect of test as compared to control implants (1.08mm (p=0.174) at 4 weeks and 0.83mm (p=0.724) at 12 weeks).

CONCLUSIONS: Hard and soft tissue healing occurred at both implant types with no statistically significant differences. Test implants tended to present a more coronal gingival margin (FGM) and first bone to implant contact (B).

PMID:34352137 | DOI:10.1111/clr.13812

Clin Oral Implants Res. 2021 Aug 5. doi: 10.1111/clr.13825. Online ahead of print.

ABSTRACT

OBJECTIVE: To evaluate the influence of artificial aging on the transformation propagation and fracture resistance of zirconia implants.

METHODS: One- [with integrated implant abutment, 1P; regular diameter (4.1mm); n=16] and two-piece [with separate implant abutment, 2P; wide diameter (5mm); n=16] zirconia implants were embedded according to ISO 14801. A two-piece titanium-zirconium implant (Ti-Zr; 4.1mm diameter) served as a control (n=16). One subgroup (n=8) of each system was simultaneously dynamically loaded (10⁷ cycles; 98N) and hydrothermally aged (85°C, 58 days) while the other subgroup (n=8) remained untreated. Finally, specimens were statically loaded to fracture. Potential crystal phase transformation was examined at cross-sections using scanning electron microscopy (SEM). A multivariate linear regression model was applied for statistical analyses.

RESULTS: The fracture resistance of 1P [1117 (SD = 38) N; loaded/aged: 1009 (60) N], 2P [850 (36) N; loaded/aged: 799 (84) N] and Ti-Zr implants [1338 (205) N; loaded/aged: 1319 (247) N] was not affected significantly by loading/aging (p=0.171). However, when comparing the systems, they revealed significant differences independent of loading/aging (p≤0.001). Regarding the crystal structure, a transformation zone was observed in SEM images of 1P only after aging, while 2P showed a transformation zone even before aging. After hydrothermal treatment, an increase of this monoclinic layer was observed in both systems.

CONCLUSIONS: The Ti-Zr control implant showed higher fracture resistance compared to both zirconia implants. Loading/aging had no significant impact on the fracture resistance of both zirconia implants. The wide body 2P zirconia implant was weaker than the regular body 1P implant.

PMID:34352139 | DOI:10.1111/clr.13825

Clin Oral Implants Res. 2021 Aug 5. doi: 10.1111/clr.13824. Online ahead of print.

ABSTRACT

OBJECTIVES: To evaluate the peri-implant tissue changes and aesthetic outcomes of cemented and screw-retained crowns of single-tooth implants in the aesthetic zone using zirconia abutments.

MATERIAL AND METHODS: An electronic search was performed on nine databases. The risk-of-bias was assessed by the revised Cochrane risk-of-bias tool for randomized (RoB 2) and non-randomized (ROBINS-I) clinical trials. Marginal bone level change, soft tissue thickness, bleeding on probing, probing depth, survival rates of implants and crowns, complications, plaque and papilla indexes, and pink aesthetic score data were extracted and analysed. The certainty of evidence was accessed through the GRADE approach.

RESULTS: Nine records were included and 7 were used in the meta-analyses. Screw-retained crowns presented greater marginal bone level change (MD -0.04 [-0.08, -0.00] p=0.04, I² =0%) compared to cemented crowns up to 1-year. At 3 and 4 years no significant differences (p>.05) were observed. Soft tissue thickness did not differ between groups (p>0.05). The bleeding on probing was higher in cemented group than in screw-retained crowns at 1-year (MD 0.17 [0.08, 0.27] p=0.0005, I² =0%), at medium-term periods (3 and 4 years) no statistically significant differences (p>0.05) were observed for this outcome. Probing depth, survival rates of implants and crowns, complications, and plaque index as well as aesthetic analysis using the papilla index and pink aesthetic score did not differ statistically (p>0.05) between both retention systems at short and medium-term periods.

CONCLUSION: The connection system considering zirconia abutments presented no influence on peri-implant parameters and aesthetics evaluation for medium-term periods (3 and 4 years).

PMID:34352144 | DOI:10.1111/clr.13824