Structured
Introduction
Of the variables used by in vitro studies of resistance to sliding (RS) in orthodontics, sliding velocity (SV) of the wire is often the one farthest from its clinical ...counterpart. We investigated whether velocity influences the RS at values approximating the orthodontic movement.
Methods
A SS self‐ligating bracket with a NiTi clip was fixed onto a custom‐made model. Different shaped orthodontic SS wires of four sizes and two types (round, 0.020″ and 0.022″; rectangular, 0.016″×0.022″ and 0.017″×0.025″) were tested using an Instron® testing machine. Wires were pulled at four velocities (1×10−2 mm/s, 1×10−3 mm/s, 1×10−4 mm/s, 1×10−5 mm/s). Shapiro‐Wilk test was used to evaluate the normal distribution of the data; two‐way ANOVA was performed to compare means in the RS with wire characteristics and SV. Significance level was set at P<.05.
Results
RS was higher for rectangular wires, and for those with larger diameters. Lower SV was associated with lower RS, with wire type and size having an interaction effect. The RS relatively to SV can be represented as: RS ∝ αln(SV)+β, where α and β are constants.
Conclusions
At very low SV and low normal forces, SV influences the RS of SS archwires in orthodontic brackets, and the proportionality is logarithmic. Although respecting these parameters in vitro is challenging, quantitative evaluations of RS should be carried out at clinically relevant velocities if aiming at translational application in the clinical scenario.
We investigated cross-sectionally whether the type 2 diabetes (T2DM) risk alleles of rs1801282 (
PPARG2
) and rs4607103 (
ADAMTS9
) were associated with T2DM and/or insulin sensitivity (IS) and beta ...cell function (βF) in Italians without and with newly diagnosed T2DM. In 676 nondiabetic subjects (336 NGR and 340 IGR) from the GENFIEV study and in 597 patients from the Verona Newly Diagnosed Type 2 Diabetes Study (VNDS), we (1) genotyped rs1801282 and rs4607103, (2) assessed βF by C-peptide/glucose modeling after OGTT, and (3) assessed IS by HOMA-IR in both studies and by euglycemic insulin clamp in VNDS only. Logistic, linear, and two-stage least squares regression analyses were used to test (a) genetic associations with T2DM and with pathophysiological phenotypes, (b) causal relationships of the latter ones with T2DM by a Mendelian randomization design. Both SNPs were associated with T2DM. The rs4607103 risk allele was associated to impaired βF (
p
< 0.01) in the GENFIEV study and in both cohorts combined. The rs1801282 genotype was associated with IS both in the GENFIEV study (
p
< 0.03) and in the VNDS (
p
< 0.03), whereas rs4607103 did so in the VNDS only (
p
= 0.01). In a Mendelian randomization design, both HOMA-IR (instrumental variables: rs1801282, rs4607103) and βF (instrumental variable: rs4607103) were related to T2DM (
p
< 0.03–0.01 and
p
< 0.03, respectively).
PPARG2
and
ADAMTS9
variants are both associated with T2DM and with insulin resistance, whereas only
ADAMTS9
may be related to βF. Thus, at least in Italians, they may be considered
bona fide
“insulin resistance genes”.
Most approved vaccines against COVID-19 have to be administered in a prime/boost regimen. We engineered a novel vaccine based on a chimeric human adenovirus 5 (hAdV5) vector. The vaccine (named ...CoroVaxG.3) is based on three pillars: (i) high expression of Spike to enhance its immunodominance by using a potent promoter and an mRNA stabilizer; (ii) enhanced infection of muscle and dendritic cells by replacing the fiber knob domain of hAdV5 by hAdV3; (iii) use of Spike stabilized in a prefusion conformation. The transduction with CoroVaxG.3-expressing Spike (D614G) dramatically enhanced the Spike expression in human muscle cells, monocytes and dendritic cells compared to CoroVaxG.5 that expressed the native fiber knob domain. A single dose of CoroVaxG.3 induced a potent humoral immunity with a balanced Th1/Th2 ratio and potent T-cell immunity, both lasting for at least 5 months. Sera from CoroVaxG.3-vaccinated mice was able to neutralize pseudoviruses expressing B.1 (wild type D614G), B.1.117 (alpha), P.1 (gamma) and B.1.617.2 (delta) Spikes, as well as an authentic P.1 SARS-CoV-2 isolate. Neutralizing antibodies did not wane even after 5 months, making this kind of vaccine a likely candidate to enter clinical trials.
Coupling hydrological models with plant physiology is crucial to capture the feedback mechanisms occurring within the soil-plant-atmosphere continuum. However, the ability of such models to describe ...the spatial variability of plant responses to different environmental factors remains to be proven, especially at large scales (field or watershed). We used an innovative three-dimensional soil-plant model to quantify temporal and spatial variability of crop productivity at the field scale, and we assessed simulation accuracy by comparison with spatially distributed crop yield measurements. A 25-ha field located in the Venice coastland, Italy, cultivated with a maize (Zea mays L.) crop and characterized by a highly heterogeneous soil subject to salt contamination, has been extensively studied by soil sampling, geophysical surveys, and hydrological monitoring. Based on these observations, field-scale simulations of soil moisture dynamics coupled with plant transpiration, photosynthesis, and growth were run and compared with crop yield maps of different growing seasons. The model captured the observed crop productivity (grain yield varying between 2 and 15 Mg ha-1), but the accuracy of the predicted spatial patterns was limited by the available information on soil heterogeneities. Further model uncertainties are related to the characterization of the rooting systems and their responses to environmental factors (soil characteristics, precipitation) that were shown to be crucial to describe the effect of drought conditions on growth processes. These results demonstrate that large-scale mechanistic simulations of soil-plant systems require a trade-off between site characterization, model processes, and computational efficiency, offering an open challenge for future ecohydrological research.
In this study, we tested the hypothesis that self-ligation can reduce the chair time necessary for inserting and removing the archwire in a fully customized, multi-bracket, orthodontic, lingual ...appliance. A permuted-block, randomized trial design was employed to treat seven patients, each with Incognito(®) lingual appliances and Harmony(®) self-ligating lingual appliances. Three operators (a third year resident in orthodontics, an orthodontic specialist, and an experienced lingual orthodontist) were instructed, and they were allowed to familiarize themselves with two typodonts. Next, the operators were asked to insert and remove a.014 NiTi customized archwire for each patient, and they were timed. The time required for removing and inserting archwires decreased proportionally with operator experience: it was shorter with self-ligating appliances (114.82±18.06 seconds versus 595.83±289.09 seconds, P < 0.001) and when testing the typodonts' performances (480.61±285.74 seconds versus 518.65±296.97 seconds, P < 0.001). However, differences between operators were smaller when using typodonts (31.77±21.19 seconds versus 43.87±27.06 seconds, P < 0.001) and with self-ligation (15.17±9.29 seconds versus 45.37±25.44 seconds, P < 0.001). In vivo performance improved after typodont training, allowing for difference reductions between operators. Lingual self-ligation appears to require less hands-on ability and training of the orthodontist, for reduction of chair time.
Abstract Background and aims Insulin resistance is a hallmark of type 2 diabetes (T2DM), it is often accompanied by defective beta-cell function (BF) and is involved in the pathophysiology of ...cardiovascular disease (CVD). Commonalities among these traits may recognize a genetic background, possibly involving the genetic variation of insulin signaling pathway genes. We conducted an exploratory analysis by testing whether common genetic variability at IRS1 , ENPP1 and TRIB3 loci is associated with cardiovascular risk traits and metabolic phenotypes in T2DM. Methods and Results In 597 drug-naïve, GADA-negative, newly-diagnosed T2DM patients we performed: 1) genotyping of 10 independent single-nucleotide polymorphisms covering ∼90% of common variability at IRS1 , ENPP1 and TRIB3 loci; 2) carotid artery ultrasound; 3) standard ECG (n = 450); 4) euglycaemic insulin clamp to assess insulin sensitivity; 5) 75 g-OGTT to estimate BF (derivative and proportional control) by mathematical modeling. False discovery rate of multiple comparisons was set at 0.20. After adjustment for age, sex and smoking status, rs4675095- T ( IRS1 ) and rs4897549- A ( ENPP1 ) were significantly associated with carotid atherosclerosis severity, whilst rs7265169- A (TRIB3) was associated with ECG abnormalities. Rs858340- G ( ENPP1 ) was significantly associated with decreased insulin sensitivity, independently of age, sex and body-mass-index. No consistent relationships were found with BF. Conclusion Some associations were found between intermediate phenotypes of CVD and common genetic variation of gatekeepers along the insulin signaling pathway. These results need be replicated to support the concept that in T2DM the CVD genetic risk clock may start ticking long before hyperglycemia appears. ClinicalTrials.gov Identifier: NCT01526720.
To assess fertilization, implantation, and pregnancy rates in patients undergoing ICSI using fresh and cryopreserved sperm from ejaculated semen samples.
Retrospective study.
Academic and private ...medical centers.
One hundred fifty-eight patients.
Intracytoplasmic sperm injection.
Fertilization, implantation, and pregnancy rates were evaluated; 61 cycles of ICSI were performed with cryopreserved and 79 cycles of ICSI were performed with fresh spermatozoa. Also, we divided the outcomes according to the semen characteristics, normozoospermia, oligozoospermia, asthenozoospermia, and oligoasthenozoospermia.
Overall, normal-fertilization rates were higher using fresh sperm (73.8%) compared with cryopreserved sperm (68.7%). Cycles performed in patients with normozoospermia or oligozoospermia had similar fertilization, implantation, and pregnancy rates using fresh or cryopreserved sperm. When asthenozoospermic and oligoasthenozoospermic semen samples were used, the normal-fertilization rate was higher with fresh sperm compared with cryopreserved sperm. However, implantation and pregnancy rates were similar in fresh and cryopreserved sperm samples from patients with asthenozoospermia or oligoasthenozoospermia.
Semen with abnormalities in the motility may be more susceptible to sperm cryopreservation damage, resulting in lower fertilization rates. However, once the oocyte is fertilized, implantation and pregnancy rates are similar to those in patients with oligozoospermia and normozoospermia.
TCF7L2 variants influence β-cell function and may play a role in determining the metabolic phenotype of patients with newly diagnosed type 2 diabetes mellitus.
Context:
Intronic variants of TCF7L2 ...are confirmed genetic risk factors for type 2 diabetes and are associated to alterations in beta cell function in nondiabetic individuals.
Objective:
The objective of the study was to test whether TCF7L2 variability may affect β-cell function also in patients with type 2 diabetes.
Design:
This was a cross-sectional association study.
Setting:
The study was conducted at a university hospital referral center for diabetes.
Patients:
Patients included 464 (315 males and 149 females) glutamic acid decarboxylase-negative patients age: median 59 yr (interquartile range: 52–65); body mass index: 29.3 kg/m2 (26.5–32.9); fasting plasma glucose: 7.0 mmol/liter (6.1–8.0) with newly diagnosed type 2 diabetes.
Intervention(s):
Interventions included frequently sampled oral glucose tolerance test and euglycemic insulin clamp.
Main Outcome Measure(s):
β-Cell function (derivative control and proportional control); insulin sensitivity; genotypes of the following TCF7L2 single-nucleotide polymorphisms: rs7901695, rs7903146, rs11196205, and rs12255372.
Results:
Both rs7901695 and rs7903146 diabetes risk alleles were associated with reduced proportional control of β-cell function (P = 0.019 and P = 0.022, respectively). Two low-frequency haplotypes were associated with extreme (best and worst) phenotypes of β-cell function (P < 0.01). No associations between TCF7L2 genotypes and insulin sensitivity were detected.
Conclusions:
TCF7L2 diabetes risk variants, either as single-nucleotide polymorphisms or as haplotypes, detrimentally influence β-cell function and might play a role in determining the metabolic phenotype of patients with newly diagnosed type 2 diabetes.
Silk fibroin (SF) is a natural biocompatible material that can be integrated in a variety of photonic systems and optoelectronics: i.e. organic lasing from dye-doped nano-structured silk film. In ...this context, biological incorporation of doping molecules into SF by means of feeding silk worms with dyes to their diet could be an innovative and eco-sustainable approach to obtain doped SF substrates, thus avoiding additional chemical processes and post-treatments of the protein solution. In the present work, we demonstrated that SF regenerated solutions and films containing rhodamine B (RhB) could be successfully obtained from the cocoons of Bombyx mori fed with a RhB-added diet (RhB-md-SF). Comparative analyses of optical and vibration characteristics of the RhB-md-SF solution and films with those of white SF blended with RhB (RhB-d-SF) revealed significant differences, suggesting that the silkworm's metabolism could be involved in the binding mechanism of SF with RhB. In conclusion, we observed that the doping diet is a promising method for the green fabrication of SF-based optically active materials, and it opens novel routes for silk-based biophotonics.
Macro-spin simulations have been performed to study the synchronization of pairs of serially connected spin torque oscillators in parallel with a capacitor. The sensitivity to the STO process ...variation, which is modeled by the anisotropy field distribution for different STO samples, can be dramatically decreased by the coupling of a capacitor in the circuit. There exists an optimum capacitance where the multi-STO synchronized state develops the highest robustness.
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