Category: Nevin Manimala

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

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

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

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

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

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

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

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

RNA. 2021 Jun 9:rna.078707.121. doi: 10.1261/rna.078707.121. Online ahead of print.

ABSTRACT

Mammalian RNA interference (RNAi) is often linked to the regulation of gene expression in the cytoplasm. Synthetic RNAs, however, can also act through the RNAi pathway to regulate transcription and splicing. While nuclear regulation by synthetic RNAs can be robust, a critical unanswered question is whether endogenous functions for nuclear RNAi exist in mammalian cells. Using enhanced crosslinking immunoprecipitation (eCLIP), we mapped AGO2 binding sites within nuclear RNA. The strongest AGO2 binding sites were mapped to micro RNAs (miRNAs). The most abundant miRNAs were distributed similarly between cytoplasm and nucleus, providing no evidence for mechanisms that facilitate localization of miRNAs in one compartment versus the other. Beyond miRNAs, most statistically-significant AGO2 binding was within introns. Splicing changes were confirmed by RT-PCR and were recapitulated by synthetic duplex RNAs and miRNA mimics complementary to the sites of AGO2 binding. These data support the hypothesis that miRNAs can control gene splicing. While nuclear RNAi proteins have the potential to be a natural regulatory mechanism, careful study will be necessary to identify critical RNA drivers of normal physiology and disease.

PMID:34108230 | DOI:10.1261/rna.078707.121

Emerg Med J. 2021 Jun 9:emermed-2020-210693. doi: 10.1136/emermed-2020-210693. Online ahead of print.

ABSTRACT

BACKGROUND: A consistent approach to cervical spine injury (CSI) clearance for patients 65 and older remains a challenge. Clinical clearance algorithms like the National Emergency X-Radiography Utilisation Study (NEXUS) criteria have variable accuracy and the Canadian C-spine rule excludes older patients. Routine CT of the cervical spine is performed to rule out CSI but at an increased cost and low yield. Herein, we aimed to identify predictive clinical variables to selectively screen older patients for CSI.

METHODS: The University of Iowa’s trauma registry was interrogated to retrospectively identify all patients 65 years and older who presented with trauma from a ground-level fall from January 2012 to July 2017. The relationship between predictive variables (demographics, NEXUS criteria and distracting injuries) and presence of CSI was examined using the generalised linear modelling (GLM) framework. A training set was used to build the statistical models to identify clinical variables that can be used to predict CSI and a validation set was used to assess the reliability and consistency of the model coefficients estimated from the training set.

RESULTS: Overall, 2312 patients ≥65 admitted for ground-level falls were identified; 253 (10.9%) patients had a CSI. Using the GLM framework, the best predictive model for CSI included midline tenderness, focal neurological deficit and signs of trauma to the head/face, with midline tenderness highly predictive of CSI (OR=22.961 (15.178-34.737); p<0.001). The negative predictive value (NPV) for this model was 95.1% (93.9%-96.3%). In the absence of midline tenderness, the best model included focal neurological deficit (OR=2.601 (1.340-5.049); p=0.005) and signs of trauma to the head/face (OR=3.024 (1.898-4.815); p<0.001). The NPV was 94.3% (93.1%-95.5%).

CONCLUSION: Midline tenderness, focal neurological deficit and signs of trauma to the head/face were significant in this older population. The absence of all three variables indicates lower likelihood of CSI for patients≥65. Future observational studies are warranted to prospectively validate this model.

PMID:34108196 | DOI:10.1136/emermed-2020-210693