Tag: statistics

NMR Biomed. 2022 Jul 11:e4800. doi: 10.1002/nbm.4800. Online ahead of print.

ABSTRACT

BACKGROUND: Quantitative MRI can detect the early biochemical changes in the cartilage; however, the conventional techniques only measure one parameter (e.g., T₁ , T₂ , and T_1ρ ) at a time while being comparatively slow.

PURPOSE: We implement a 3D-magnetic resonance fingerprinting (3D-MRF) technique for simultaneous, volumetric mapping of T₁ , T_2, and T_1ρ in the knee articular cartilage under 9 minutes.

STUDY TYPE: Prospective.

FIELD STRENGTH/SEQUENCE: 3D-MRF pulse sequence for 3T.

SUBJECTS AND PHANTOM: 11 healthy volunteers (mean age: 53 ± 9) and 5 mild knee OA patients (KL:2, mean age: 60 ± 4) and NIST/ISMRM system phantom ASSESSMENT: Proton density (PD) image, and T₁ , T_2, T_1ρ relaxation times, and B₁⁺ were estimated in NIST/ISMRM system phantom as well as the human knee medial (MFC) and lateral (LFC) femur, medial (MTC) and lateral (LTC) tibia, and patellar cartilages (PC).

STATISTICAL TESTS: The repeatability and reproducibility of the proposed technique were assessed in the phantom using the analysis of the Bland-Altman plots. The intra-subject repeatability was assessed with the coefficient of variation (CV), and the root mean square CV (rmsCV). Mann-Whitney U test was used to assess the difference between healthy subjects and mild knee OA patients.

RESULTS: The Bland-Altman plots in the NIST/ISMRM phantom demonstrated an average difference of 0.001 ± 015%, 1.2 ± 7.1%, and 0.47 ± 3% between two scans from the same 3T scanner (repeatability), and 0.002 ± 015%, 0.62 ± 10.5%, and 0.97 ± 14% between the scans acquired on two different 3T scanners (reproducibility) for T₁ , T₂ , and T_1ρ , respectively. The in-vivo knee study showed excellent repeatability with rmsCV less than 1%, 2%, and 1% for T₁ , T₂ , and T_1ρ , respectively. T_1ρ relaxation time in the mild knee OA patients was significantly higher (p < 0.05) than in healthy subjects.

DATA CONCLUSION: The proposed 3D-MRF sequence is fast, reproducible, robust to B₁⁺ inhomogeneity, and can simultaneously measure the T₁ , T₂ , T_1ρ , and B₁⁺ volumetric maps of the knee joint in a single scan within clinically feasible scan time.

PMID:35815660 | DOI:10.1002/nbm.4800

Minim Invasive Ther Allied Technol. 2022 Jul 10:1-8. doi: 10.1080/13645706.2022.2094710. Online ahead of print.

ABSTRACT

The aim of this study is to perform a systematic review and meta-analysis of published studies to evaluate the efficacy and safety of computed tomography (CT)-guided percutaneous biopsy for retroperitoneal lesions. PubMed and the Cochrane Library were searched for English-language articles published up to October 2021 and reporting findings about patients with retroperitoneal lesions who underwent CT-guided percutaneous biopsy. The outcome measures assessed in this systematic review and meta-analysis are accuracy, false negative rate, and rate of minor and major complications. Heterogeneity among studies was evaluated by testing Cochran’s Q and the inconsistency index statistics. Seven studies published from 1975 to 2021 were selected for the analysis of accuracy, false negative rates, and rate of major and minor complications. The pooled accuracy of CT-guided percutaneous biopsy for retroperitoneal lesions was 93.6% [95% confidence interval (CI), 88.1-96.6%], with high heterogeneity. The pooled false negative rate was 6.3% (95% CI, 3.3-11.7%) with high heterogeneity. Pooled rates of minor and major complications were 3.7% (95% CI, 1.6-8.6%) with moderate heterogeneity and 0.7% (95% CI, 0.4-1.1%) with low heterogeneity, respectively. CT-guided percutaneous biopsy for retroperitoneal lesions has been reported to have high accuracy with a limited rate of major complications.

PMID:35815633 | DOI:10.1080/13645706.2022.2094710

Anat Histol Embryol. 2022 Jul 11. doi: 10.1111/ahe.12835. Online ahead of print.

ABSTRACT

Cartilage differentiates in rat limb buds cultivated in a chemically defined protein-free medium in the same manner as in the richer serum-supplemented medium. We aimed to investigate the remaining differentiation potential of pre-cultivated limb buds by subsequent transplantation in vivo. Rat front (FLBs) and hind-limb buds (HLBs) were isolated from Fischer rat dams at the 14th gestation day (GD 14) and cultivated at the air-liquid interface in Eagle’s Minimum Essential Medium (MEM) alone; with 5 μM of 5-azacytidine (5azaC) or with rat serum (1:1). Overall growth was measured seven times during the culture by an ocular micrometre. After 14 days, explants were transplanted under the kidney capsule of adult males. Growth of limb buds was significantly lower in all limb buds cultivated in MEM than in those cultivated with serum. In MEM with 5azaC, growth of LBs was significantly lower only on day 3 of culture. Afterwards, it was higher throughout the culture period, although a statistically significant difference was assessed only for HLBs. In transplants, mixed structures developed with the differentiated transmembranous bone, cartilage with enchondral ossification, bone-marrow, sebaceous gland, and hair that have never been found in vitro. Nerves differentiated only in transplants precultivated in the serum-supplemented medium. We conclude that pre-cultivation of LBs in a chemically defined protein-free medium does not restrict osteogenesis and formation of epidermal appendages but is restrictive for neural tissue. These results are important for understanding limb development and regenerative medicine strategies.

PMID:35815632 | DOI:10.1111/ahe.12835

Vet Comp Orthop Traumatol. 2022 Jul 10. doi: 10.1055/s-0042-1750433. Online ahead of print.

ABSTRACT

OBJECTIVE: The aim of this study was to compare the accuracy of pedicle screw placement at the canine lumbosacral junction using a novel unilateral three-dimensional printed patient-specific guide (3D-PSG) versus a freehand drilling technique. Additionally, accuracy of screw placement between a novice and an experienced surgeon was determined.

STUDY DESIGN: Preoperative computed tomography images from 20 lumbosacral cadaveric specimens were used to design a novel unilateral 3D-PSG for the L7 and sacral vertebrae which was printed in acryl-nitrile butadiene styrene plastic. A novice and an expert surgeon each placed 3.5mm cortical screws in 10 cadavers; on the left using the unilateral 3D-PSG and by the freehand (anatomic landmark) technique on the right.

RESULTS: Sixty screws were placed using the unilateral 3D-PSG and 60 using the freehand technique. There was no statistical difference in accuracy for the comparison between methods performed by the expert (p = 0.679) and novice (p = 0.761) surgeon, nor between an expert and novice surgeon overall (p = 0.923). Unexpectedly, the use of a unilateral 3D-PSG increased variability for the expert surgeon in our study (p = 0.0314).

CONCLUSION: Using a novel unilateral 3D-PSG did not improve the accuracy of screw placement for lumbosacral stabilization by a novice surgeon compared with an expert surgeon in lumbar spine surgery. This may reflect a suboptimal PSG design.

PMID:35815627 | DOI:10.1055/s-0042-1750433

Hand (N Y). 2022 Jul 9:15589447221105540. doi: 10.1177/15589447221105540. Online ahead of print.

ABSTRACT

BACKGROUND: Many techniques are used for digital nerve repair, most commonly coaptation by sutures. Nerve repairs must be strong while offering an environment for nerve regeneration. Sutures can damage the nerve and thereby limit growth and regeneration. Sutures can rip and cause sudden catastrophic failure. Fibrin glue and conduit-wraps allow a good environment for growth, but neither provides much strength. A benefit to conduit repair would arise if the repair maintained integrity after the peak load so that the path for regrowth stayed in place. The goal for this study was to determine whether conduit with glue provides continued strength after a maximum load is reached.

METHODS: Digital cadaveric nerves were harvested and repaired with 2 epineurial sutures, conduit, and fibrin glue in all combinations. Tests to failure were performed, gap displacement between nerve ends recorded, and the postpeak load energy to dissociation of the nerve and conduit was calculated.

RESULTS: Conduit with glue and 2 sutures at the end had the greatest energy and displacement after the peak load but was not significantly different than conduit with glue and 1 suture. Conduit with glue alone obtained statistically the same displacement as conduit with glue and 2 sutures. Conduit, with or without glue, and 2 sutures was statistically the same as suture only repair for peak load.

CONCLUSION: Conduit/wrap maintains a load capacity and a path for nerve regeneration after the peak. Suture at the ends of conduit, not at the coaptation site, reduces damage at the point of injury.

PMID:35815624 | DOI:10.1177/15589447221105540

Epidemiol Psychiatr Sci. 2022 Jul 11;31:e48. doi: 10.1017/S2045796022000348.

ABSTRACT

AIMS: The mounting evidence for effective delivery of psychological interventions by non-specialists in low- and middle-income settings has led to a rapid expansion of mental health and psychosocial support trainings globally. As such, there is a demand for strategies on how to train and implement these services to attain adequate quality. This study aims to evaluate the added value of a competency-driven approach to training of facilitators for a group intervention for children with severe emotional distress in Lebanon.

METHODS: In a controlled before and after study, 24 trainees were randomly allocated to participate in either a competency-driven training (CDT) or training-as-usual (TAU) (1 : 1) for a psychological intervention for children with severe emotional distress. We assessed the change in demonstrated competencies, using standardised role-plays, before and after the training. Measures included the 13-item Working with children-Assessment of Competencies Tool (WeACT), the 15-item ENhancing Assessment of Common Therapeutic factors (ENACT) and the 6-item Group facilitation: Assessment of Competencies Tool (GroupACT). The trainer in the experimental arm used pre-training and during training competency assessment scores to make real-time adjustment to training delivery. Due to COVID-19 pandemic restrictions, all activities were done remotely.

RESULTS: CDT resulted in significantly better outcomes on increasing competencies on the WeACT (repeated measures analysis of variance; F_{(1, 22)} = 6.49, p < 0.018) and on the GroupACT (Mann-Whitney U = 22, p < 0.003), though not statistically significant on the ENACT. There is no significant between-group difference on the reduction of harmful behaviours, mainly because both forms of training appear equally successful in eliminating such behaviours.

CONCLUSIONS: This proof-of-concept study demonstrates the potential of CDT, using standardised assessment of trainee competencies, to contribute to better training outcomes without extending the duration of training. CDT can result in up to 18% greater increase in adequate competency, when compared to TAU. The study also yields recommendations for further enhancing the benefits of competency-driven strategies. A fully powered trial is needed to confirm these findings.

PMID:35815622 | DOI:10.1017/S2045796022000348

Ann Hum Biol. 2022 Jul 11:1-22. doi: 10.1080/03014460.2022.2100477. Online ahead of print.

ABSTRACT

BACKGROUND: CYP3A5 enzyme encoded by CYP3A5 is important for drug metabolism in gut and liver, whereas P-glycoprotein by ABCB1, is an ATP-dependent drug efflux pump which exports endo- and exogenous substances outside the cell. Aim: The study was to assess the prevalence of CYP3A5 alleles: *1, *2, *3, *4, *6 and *7, and C and T of ABCB1 in Poles, Belarusians and Bosnians and to compare it with the data reported from other European populations. Subjects and methods: Overall, 511 unrelated healthy subjects from Poland (n = 239), Belarus (n = 104) and Bosnia and Herzegovina (n = 168) were included in this study. Allele frequencies and statistical parameters (AMOVA version 2.9.3) were determined. Results: In Poles, Belarusians and Bosnians the *3 allele of CYP3A5 was the most common, and wild-type allele *1, were: 5.8%, 1.6% and 2.1%, respectively. Allele *2 was very rare, and alleles *4, *6 and *7 were not detected. For the populations mentioned above, the ABCB1 allele C was: 48.1%, 51.4%, 52.4%, respectively.

CONCLUSION: In compared populations, the distribution of CYP3A5 variants but not ABCB1, differed significantly. Alleles *4, *6 and *7 of CYP3A5 did not occur or occurred rarely.

PMID:35815612 | DOI:10.1080/03014460.2022.2100477

J Phys Chem B. 2022 Jul 10. doi: 10.1021/acs.jpcb.2c03676. Online ahead of print.

ABSTRACT

The abnormal aggregation of α-synulcein is associated with multiple neurodegenerative diseases such as Parkinson’s disease. The hydrophobic non-amyloid component (NAC) region of α-synuclein comprises the core of the fibril in vitro and in vivo. In this work, we study the aggregation landscape of the hydrophobic NAC region of α-synuclein using a transferrable coarse-grained force field, the associative memory water-mediated structure, and energy model (AWSEM). Using structural similarity, we can group metastable states on the free energy landscape of aggregation into three types of oligomers: disordered oligomers, prefibrillar oligomers with disordered tips, and ordered prefibrillar oligomers. The prefibrillar oligomers with disordered tips have more in-register parallel β strands than do the fully disordered oligomers but have fewer in-register parallel β strands than the ordered prefibrillar oligomers. Along with the ordered prefibrillar species, the disordered oligomeric states dominate at small oligomer sizes while the prefibrillar species with disordered tips thermodynamically dominate with the growth of oligomers. The topology of the aggregation landscape and observations in simulations suggest there is backtracking between ordered prefibrillar oligomers and other kinds of oligomers as the aggregation proceeds. The significant structural differences between the ordered prefibrillar oligomers and the disordered oligomers support the idea that the growth of these two kinds of oligomers involves kinetically independent parallel pathways. In contrast, the overall structural similarity between the fully ordered prefibrillar oligomers and the prefibrillar oligomers with disordered tips implies that two channels can interconvert on slower time scales. We also evaluate the effects of phosphorylation on the aggregation free energy landscape using statistical mechanical perturbation theory.

PMID:35815598 | DOI:10.1021/acs.jpcb.2c03676

Am J Perinatol. 2022 Jul 10. doi: 10.1055/s-0042-1750119. Online ahead of print.

ABSTRACT

INTRODUCTION: Respiratory conditions are the most common reason for admission of newborns to a neonatal care unit. The index of contractility (ICON) can be used to measure the thoracic fluid content (TFC) in neonates which is a significant parameter in cases presented with transient tachypnea of newborn (TTN).

OBJECTIVE: The objective was to compare TFC between newborn infants with TTN compared with other causes of respiratory distress (RD). We tested the hypothesis that TFC would be higher in infants with TTN.

STUDY DESIGN: In total, 105 newborns were enrolled at the delivery room and were categorized into three groups: TTN, other causes of RD, and control, according to physical examination and Chest X-Ray. TFC was measured within the first 6 hours for all infants and at 24 and 48 hours for the first two groups.

RESULTS: Demographic data showed higher male participants and use of antenatal steroid therapy in RD groups. TFC within the first 6 hours was higher in RD groups. However, TFC at 24 hours of ≤24 mL/kg, and TFC drop rate at 24 hours of >12% are statistically significant discriminators of TTN from non-TTN, with sensitivity and specificity of 97.1 and 47.1%, and 60 and 82.4%, respectively (Fig 1 and 2).

CONCLUSION: ICON can be used in conjunction with clinical parameters and CXR as a tool for differentiation between TTN and other causes of RD within the first 24 hours of life by using the cutoff value of TFC at 24 hours and TFC drop rate. This will allow earlier and optimum management of different causes of RD.

KEY POINTS: · Thoracic fluid content. · Neonatal respiratory distress. · Newborn.

PMID:35815571 | DOI:10.1055/s-0042-1750119

EMBO Rep. 2022 Jul 11:e55642. doi: 10.15252/embr.202255642. Online ahead of print.

NO ABSTRACT

PMID:35815565 | DOI:10.15252/embr.202255642