Categories
Nevin Manimala Statistics

Heart Rate Variability and Pain Sensitivity in Chronic Low Back Pain Patients Exposed to Passive Viewing of Photographs of Daily Activities

Clin J Pain. 2021 Jun 9. doi: 10.1097/AJP.0000000000000953. Online ahead of print.

ABSTRACT

OBJECTIVES: We sought to investigate emotional reactivity by measuring HRV and pressure pain sensitivity during a passive visualization task in participants with chronic low back pain (CLBP).

METHODS: This case-control study was composed of 47 participants with CLBP and 47 asymptomatic participants. Both groups were submitted to a passive visualization task using 27 pictures from PHODA (Photograph Series of Daily Activities). HRV frequency domains were measured before, during, and after the task. Pressure pain threshold (PPT) and pain intensity were also measured before and after the task.

RESULTS: The adjusted mean difference was statistically significant for HRV frequency domains during the visualization task, including low frequency (-5.92; 95%CI=-9.60 to -2.23), high frequency (-0.71; 95%CI=-1.02 to -0.39), and low frequency/high frequency ratio (8.82; 95%CI=5.19 to 12.45). PPT decreased after the task in the low back pain group in all body sites, and pain intensity increased (-0.8; 95% CI=-1.16 to -0.39).

DISCUSSION: Aversive environmental stimuli, such as visual cues, may generate defensive physiological reactions. Heart rate variability (HRV) can provide an available measure that reflects the perceptions of threat and safety in the environment. Participants with chronic low back pain presented changes in sympathovagal balance during passive visualization of pictures of daily activities, higher pain sensitivity, and high pain intensity when they are exposed to a passive visualization task using pictures of daily living that may arouse fears of harm.

PMID:34108363 | DOI:10.1097/AJP.0000000000000953

Categories
Nevin Manimala Statistics

Long-Term Outcomes of a Community of Practice for Dietitians Working in Aboriginal and Torres Strait Islander Health: A Multimethod, Follow-up Study

J Contin Educ Health Prof. 2021 Jun 8. doi: 10.1097/CEH.0000000000000370. Online ahead of print.

ABSTRACT

INTRODUCTION: Dietitians are in an important position to work alongside Aboriginal and Torres Strait Islander peoples to improve their health and may play a role in reducing the burden of disease experienced by Aboriginal and Torres Strait Islander peoples. Many dietitians do not feel confident to practice effectively in these settings and require improved workforce development opportunities. Communities of Practice can improve dietitians’ confidence and practice in Aboriginal and Torres Strait Islander health; however, evidence for long-term impacts is limited. This study aims to determine if a Community of Practice can have long-term impacts on dietitians working in Aboriginal and Torres Strait Islander health.

METHODS: Data were collected through semistructured interviews and a cultural awareness self-assessment tool. Analysis was through a multimethod approach and combined qualitative inductive thematic analysis, social network analysis, and descriptive statistics.

RESULTS: Three main areas of long-term impact were identified including development of a social and professional network, career progression and retention, and a fundamental change in thinking and practice. All participants experienced feelings of support and increased confidence.

DISCUSSION: Communities of practice may be a feasible, low-cost workforce development strategy that can reduce dietitians’ feelings of professional isolation when working in Aboriginal and Torres Strait Islander health. Further research is required to identify the mechanisms underlying sustained impacts. Social network analysis, combined with realist evaluation may be an appropriate research design, to answer future and more in-depth questions about the effectiveness of communities of practice.

PMID:34108390 | DOI:10.1097/CEH.0000000000000370

Categories
Nevin Manimala Statistics

Does Women’s Screening History Have Any Impact on Mammography Screening Attendance After Tailored Education?: A Systematic Review and Meta-analysis

Med Care. 2021 Jun 9. doi: 10.1097/MLR.0000000000001576. Online ahead of print.

ABSTRACT

BACKGROUND: Many ethnic minority women have low attendance at breast cancer screening.

OBJECTIVES: This brief report explores whether women’s screening histories impact mammography screening attendance after tailored education.

RESEARCH DESIGN: Systematic searches were conducted in 5 databases. Randomized controlled trials of educational interventions tailored to ethnic minority women that measured attendance at mammography screening were eligible for inclusion. Data extraction and risk of bias assessment were performed independently. Data were combined in a meta-analysis by using random effects models. Heterogeneity was estimated by using I2 statistics.

RESULTS: Six studies with 3521 women were eligible for inclusion. The D+L pooled risk ratio (RR) for mammography attendance for never screened participants was 1.54 (95% confidence interval, 1.24-1.91; P<0.001), with low heterogeneity (I2=27.1%, P=0.231). The D+L pooled risk ratio for attendance for ever screened participants was 1.26 (95% confidence interval, 1.11-1.43; P<0.001), with low heterogeneity (I2=35.5%, P=0.213).

CONCLUSIONS: Tailored education increased attendance at mammography by 54% among never screened women and 26% among ever screened women. Although these findings must be interpreted with caution, the findings suggest that women’s screening history is an important and ignored variable that affects how effective tailored education is on mammography screening attendance.

PMID:34108408 | DOI:10.1097/MLR.0000000000001576

Categories
Nevin Manimala Statistics

The effect of resin cement shade and restorative material type and thickness on the final color of resin-matrix ceramics

J Prosthodont Res. 2021 Jun 10. doi: 10.2186/jpr.JPR_D_20_00138. Online ahead of print.

ABSTRACT

PURPOSE: This study aims to evaluate the effects of cement shade, restorative material type, and thickness on the final color of resin-matrix ceramics.

METHODS: Ninety A2 shade resin-matrix ceramic specimens were prepared from Vita Enamic, GC Cerasmart, and Lava Ultimate at 0.5 and 1.0 mm thicknesses. Sixty resin cement disks were fabricated from different shades (A1, A3O, B05, and TR) of RelyX Ultimate at 0.1 mm thickness. CIE color coordinates were measured using a spectrophotometer, and color differences (∆ E 00 ) were calculated. Data were statistically analyzed (P =0.05).

RESULTS: The ΔE 00 values were influenced by the cement shade, restorative material type, thickness, and their interactions ( P < 0.05). A3O cement caused clinically unacceptable values for all groups at 0.5 mm thickness and GC at 1.0 mm thickness. A1 and TR cement shades demonstrated visually perceptible but clinically acceptable values, except for VE-A1 and LU-A1 at 0.5 mm thickness. The ∆E 00 values of the B05 cement shade were lower than the visually perceptible threshold for both thicknesses except for GC at 0.5 mm thickness.

CONCLUSIONS: The shade of the resin cement and the type and thickness of the resin-matrix ceramic material significantly affected the resulting final color. To provide a shade matching with natural dentition and to obtain esthetic restorations, especially for the anterior teeth, the resin cement shade and resin-matrix ceramic material should be carefully selected.

PMID:34108295 | DOI:10.2186/jpr.JPR_D_20_00138

Categories
Nevin Manimala Statistics

Fatigue failure and success rate of lithium disilicate table-tops as a function of cement thickness

J Prosthodont Res. 2021 Jun 10. doi: 10.2186/jpr.JPR_D_20_00220. Online ahead of print.

ABSTRACT

PURPOSE: Under thin, partial coverage restoration the proper cement thickness to be clinically employed still remains an issue. The aim of this study was to determine the failure and success rates of simplified lithium disilicate occlusal veneers as a function of cement thickness. The null hypothesis was that cement thickness has no effect on the fatigue resistance.

METHODS: Sound human molars were severed in a plane parallel to the occlusal surface to create a flat dentin surface surrounded by enamel edges. Forty-five occlusal veneers 1.0 mm thick (IPS e.max CAD LT) were luted to the teeth with Multilink Automix resin cement, creating 3 experimental groups (n=15) with cement thicknesses of 50, 100, and 200 µm. The restorations were fatigue-cycled using a ball mill machine containing zirconia and stainless steel spheres. Twelve 60 min cycles were performed. Survival statistics were applied to “failure” and “success” events, comparing the three groups using a log-rank Mantel-Cox test and a log-rank test for trends (alpha = 0.05).

RESULTS: The failure and success rates were not significantly influenced by cement thickness (P = 0.137 and P = 0.872, respectively); thus, the null hypothesis was accepted. However, when log-rank test for trends was applied to failure events, the tendency to have less failures with increasing thicknesses was found statistically significant (P = 0.047).

CONCLUSIONS: The cement thickness within the range adopted here did not have a significant effect on the failure or success rate of lithium disilicate occlusal veneers when exposed to randomized impact stresses generating fatigue phenomena.

PMID:34108297 | DOI:10.2186/jpr.JPR_D_20_00220

Categories
Nevin Manimala Statistics

Fracture resistance of maxillary premolars restored with different endocrown designs and materials after artificial ageing

J Prosthodont Res. 2021 Jun 10. doi: 10.2186/jpr.JPR_D_20_00082. Online ahead of print.

ABSTRACT

PURPOSE: To evaluate the effect of three different designs and two monolithic ceramic materials on the durability and fracture resistance of endocrowns on maxillary first premolars, in comparison to post-and-core crowns.

METHODS: Fifty-six maxillary premolars were endodontically treated and shortened to a level of 2 mm from the cervical line, and randomly categorized into six endocrown groups and post-and-core crown control group (n=8); E1; endocrowns with flat occlusal table (without ferrule), E2; endocrowns with 1.5 mm circumferential ferrule, E3; endocrowns with 1.5 mm buccal ferrule preparation. Two materials were used for endocrowns: zirconia (4YSZ; Z), and lithium disilicate (L). The control group was restored with zirconia posts, and lithium disilicate crowns. All restorations were bonded using Panavia V5 and its respective primers and underwent thermo-mechanical fatigue with a 10 kg dynamic load for 1,200,000 cycles and thermocycling between 5 and 55 °C. Thereafter all survived specimens were loaded to fracture. The results were statistically analyzed using ANOVA and T-Test.

RESULTS: None of the specimens showed any signs of debonding or fracture caused by the fatigue test. The PC control group showed no statistically significant difference in comparison to groups ZE1, ZE2 and LE2 ( p > 0.05 ). However, it was significantly different from groups LE1, LE3, and ZE3 ( p ≤ 0.05 ).

CONCLUSIONS: Preparation designs and materials affected the fracture resistance of endocrowns. The results showed a superiority of the post-and-core crowns,zirconia/lithium disilicate endocrowns with 1.5 mm circumferential ferrule, and zirconia endocrowns with the flat occlusal table.

PMID:34108294 | DOI:10.2186/jpr.JPR_D_20_00082

Categories
Nevin Manimala Statistics

A phase 2 trial of inhaled nitrous oxide for treatment-resistant major depression

Sci Transl Med. 2021 Jun 9;13(597):eabe1376. doi: 10.1126/scitranslmed.abe1376.

ABSTRACT

Nitrous oxide at 50% inhaled concentration has been shown to improve depressive symptoms in patients with treatment-resistant major depression (TRMD). Whether a lower concentration of 25% nitrous oxide provides similar efficacy and persistence of antidepressant effects while reducing the risk of adverse side effects is unknown. In this phase 2 clinical trial (NCT03283670), 24 patients with severe TRMD were randomly assigned in a crossover fashion to three treatments consisting of a single 1-hour inhalation with (i) 50% nitrous oxide, (ii) 25% nitrous oxide, or (iii) placebo (air/oxygen). The primary outcome was the change on the Hamilton Depression Rating Scale (HDRS-21). Whereas nitrous oxide significantly improved depressive symptoms versus placebo (P = 0.01), there was no difference between 25 and 50% nitrous oxide (P = 0.58). The estimated differences between 25% and placebo were -0.75 points on the HDRS-21 at 2 hours (P = 0.73), -1.41 points at 24 hours (P = 0.52), -4.35 points at week 1 (P = 0.05), and -5.19 points at week 2 (P = 0.02), and the estimated differences between 50% and placebo were -0.87 points at 2 hours (P = 0.69), -1.93 points at 24 hours (P = 0.37), -2.44 points at week 1 (P = 0.25), and -7.00 points at week 2 (P = 0.001). Adverse events declined substantially with dose (P < 0.001). These results suggest that 25% nitrous oxide has comparable efficacy to 50% nitrous oxide in improving TRMD but with a markedly lower rate of adverse effects.

PMID:34108247 | DOI:10.1126/scitranslmed.abe1376

Categories
Nevin Manimala Statistics

1,3-Butadiene, styrene and lymphohaematopoietic cancers among North American synthetic rubber polymer workers: exposure-response analyses

Occup Environ Med. 2021 Jun 9:oemed-2020-107197. doi: 10.1136/oemed-2020-107197. Online ahead of print.

ABSTRACT

OBJECTIVE: To evaluate exposure-response between 1,3-butadiene, styrene and lymphohaematopoietic cancers in an updated cohort of workers at six North American plants that made synthetic rubber polymers.

METHODS: Employees were followed from 1943 through 2009 to determine mortality outcomes. Cox regression analyses estimated rate ratios (RRs) and 95% CIs by quartile of cumulative exposure to butadiene or styrene, measured in parts per million-years (ppm-years), and exposure-response trends for all leukaemia, lymphoid leukaemia, myeloid leukaemia, acute myeloid leukaemia, non-Hodgkin’s lymphoma (NHL), multiple myeloma and all B-cell malignancies.

RESULTS: Among 21 087 workers, adjusted RRs for butadiene and all leukaemia (132 deaths) rose with increasing exposure, with an RR of 2.53 (95% CI 1.37 to 4.67) in the highest exposure quartile (≥363.64 ppm-years), and the exposure-response trend was statistically significant for all leukaemia (p=0.014) and for lymphoid leukaemia (52 deaths, p=0.007). Styrene exposure-response trends for all leukaemia and lymphoid leukaemia were less consistent than those for butadiene. Cumulative exposures to butadiene and styrene were not associated consistently with myeloid leukaemias or the B-cell malignancies, NHL and multiple myeloma.

CONCLUSIONS: We confirmed a positive exposure-response relationship between butadiene and all leukaemia among workers, most of whom had coexposure to styrene. Results supported an association between butadiene and lymphoid leukaemia, but not myeloid leukaemia, and provided little evidence of any association of butadiene or styrene exposures with major subtypes of B-cell malignancies other than lymphoid leukaemia, including NHL and multiple myeloma.

PMID:34108254 | DOI:10.1136/oemed-2020-107197

Categories
Nevin Manimala Statistics

The effect of recombination on the evolution of a population of Neisseria meningitidis

Genome Res. 2021 Jun 9. doi: 10.1101/gr.264465.120. Online ahead of print.

ABSTRACT

Neisseria meningitidis (the meningococcus) is a major human pathogen with a history of high invasive disease burden, particularly in sub-Saharan Africa. Our current understanding of the evolution of meningococcal genomes is limited by the rarity of large-scale genomic population studies and lack of in-depth investigation of the genomic events associated with routine pathogen transmission. Here, we fill this knowledge gap by a detailed analysis of 2839 meningococcal genomes obtained through a carriage study of over 50,000 samples collected systematically in Burkina Faso, West Africa, before, during, and after the serogroup A vaccine rollout, 2009-2012. Our findings indicate that the meningococcal genome is highly dynamic, with highly recombinant loci and frequent gene sharing across deeply separated lineages in a structured population. Furthermore, our findings illustrate how population structure can correlate with genome flexibility, as some lineages in Burkina Faso are orders of magnitude more recombinant than others. We also examine the effect of selection on the population, in particular how it is correlated with recombination. We find that recombination principally acts to prevent the accumulation of deleterious mutations, although we do also find an example of recombination acting to speed the adaptation of a gene. In general, we show the importance of recombination in the evolution of a geographically expansive population with deep population structure in a short timescale. This has important consequences for our ability to both foresee the outcomes of vaccination programs and, using surveillance data, predict when lineages of the meningococcus are likely to become a public health concern.

PMID:34108268 | DOI:10.1101/gr.264465.120

Categories
Nevin Manimala Statistics

Macular sensitivity assessment and fixation analysis using microperimetry in children with retinopathy of prematurity

Br J Ophthalmol. 2021 Jun 9:bjophthalmol-2021-319352. doi: 10.1136/bjophthalmol-2021-319352. Online ahead of print.

ABSTRACT

BACKGROUND/AIMS: To investigate retinal sensitivity and fixation stability using microperimetry in children with retinopathy of prematurity (ROP).

METHODS: Observational case series. Totally 51 preterm children who had been followed for ROP were examined in three groups (n=17 in each group). The groups were defined as children without ROP (group 1), children with spontaneously resolved ROP (group 2) and children who had laser treatment for ROP (group 3). All subjects underwent a detailed ophthalmic examination. Macular Analyzer Integrity Assessment Microperimetry was used to analyse macular light sensitivity and fixation stability. The results were compared between groups. The measurements were also analysed according to age, gender, birth weight and gestational age.

RESULTS: The mean age was 10.84±0.97 years, and 27 children were female. Mean average threshold (AT) for macular sensitivity was 25.5±2.1 decibel in group 1, 26.8±3.8 decibel in group 2 and 26.3±3.0 decibel in group 3. These differences were not statistically significant between the groups (p=0.067), but AT was abnormal in 29% of the whole study population. Outputs about fixation stability were similar between the three groups but fixation was unstable in 27% of the subjects. Mean AT was better in children ≥11 years old compared with the younger ones (p=0.022).

CONCLUSION: Preterm children may have some abnormalities in macular light sensitivity and fixation stability. These abnormalities may be more prominent in children less than 11 years old. ROP itself or the laser treatment seems not to affect macular light sensitivity and fixation stability.

PMID:34108227 | DOI:10.1136/bjophthalmol-2021-319352