Adverse effect of botulinum toxin-A injections on mandibular bone: A systematic review and meta-analysis.

INTRODUCTION: Botulinum toxin-A (BTX) is a potent neurotoxin that is emerging in the scope of dental practice for its ability to temporarily paralyse musculature and reduce hyperfunction. This may be desirable in diseases/disorders associated with hyperactive muscles such as the muscles of mastication, most implicated in painful temporomandibular disorders (TMDs). The use of BTX extends beyond its indications with off-label use in TMD's and other conditions, while potential adverse effects remain understudied. BTX is well-established hindlimb paralysis model in animals leading to significant bone loss with underlying mechanisms remaining unclear. The objective of this study is to systematically review the literature for articles investigating changes in mandibular bone following BTX injections and meta-analyse available data on reported bone outcomes. METHODS: Comprehensive search of Medline, Embase and Web of Science retrieved 934 articles. Following the screening process, 36 articles in animals and humans were included for quantitative synthesis. Articles in human individuals (6) and three different animal species (14) presented mandibular bone outcomes that were included in the meta-analysis. RESULTS: The masseter and temporalis muscles were frequently injected across all species. In humans, we observe a decrease of about 6% in cortical thickness of mandibular regions following BTX injection with no evident changes in either volume or density of bone structures. In animals, bone loss in the condylar region is significantly high in both cortical and trabecular compartments. DISCUSSION: Our analysis supports the concept of BTX-induced bone-loss model in animal mandibles. Further, bone loss might be confined to the cortical compartments in humans. Most studies did not address the reality of repeated injections and excessive dosing, which occur due to the reversible action of BTX. More rigorous trials are needed to draw a full picture of potential long-term adverse effects on bone.

Personal elearning management in the context of COVID-19 among university students in Saudi Arabia.

The study aimed to study the performance expectation in future tasks based on personal learning management during the Corona epidemic. A random sample of 871 students from the University of Hail was selected. The study samples were from humanities, engineering, and medical colleges. The study was based on a cross-sectional study design. The study prepared a measure of future expectation of performance on the tasks. The scale is 28 items. Factor analysis was used to verify the validity of the scale, and the scale achieved acceptable indicators of good fit. The scale achieved acceptable stability using Cronbach's alpha coefficient for emotional factor 0.57, cognitive factor 0.94, and behavioral factor 0.90. The results revealed that there are differences in the future expectation on performance because of gender and type of college. The results revealed that there are positive correlations between future expectation of cognitive and emotional performance, as well as a positive relationship between emotional and behavioral performance. There was also a negative relationship between behavioral and cognitive performance.

L'étude visait à étudier les attentes de performance dans les tâches futures basées sur la gestion de l'apprentissage personnel pendant l'épidémie de Corona. Un échantillon aléatoire de 871 étudiants de l'Université de Hail a été sélectionné. Les échantillons de l'étude provenaient de facultés de sciences humaines, d'ingénierie et de médecine. L'étude était basée sur une conception d'étude transversale. L'étude a préparé une mesure des attentes futures en matière de performance pour les tâches. L'échelle est de 28 items. L'analyse factorielle a été utilisée pour vérifier la validité de l'échelle, et celle-ci a atteint des indicateurs acceptables de bon ajustement. L'échelle a atteint une stabilité acceptable en utilisant le coefficient alpha de Cronbach pour le facteur émotionnel de 0,57, le facteur cognitif de 0,94 et le facteur comportemental de 0,90. Les résultats ont révélé qu'il existe des différences dans les attentes futures en matière de performance en raison du sexe et du type d'université. Les résultats ont révélé qu'il existe des corrélations positives entre les attentes futures en matière de performances cognitives et émotionnelles, ainsi qu'une relation positive entre les performances émotionnelles et comportementales. Il existe également une relation négative entre les performances comportementales et cognitives.

Efficacy of antiresorptive agents in fibrous dysplasia and McCune Albright syndrome, a systematic review and meta-analysis.

Fibrous dysplasia (FD) is a rare skeletal disorder in which normal bone is replaced by a fibro-osseous tissue, resulting in possible deformities and fractures. The aim of this systematic review and meta-analysis was to synthesize the available evidence on the use of antiresorptive drugs in FD in terms of changes in bone turnover markers (BTMs), bone mineral density (BMD), and reducing pain. Three databases were searched in October 2022, with an update in July 2023. Of the 1037 studies identified, 21 were retained after eligibility assessment. A random-effects model was used to calculate global effect size and the corresponding standard error. Pamidronate and Denosumab were the most reported drugs in a total of 374 patients assessed. The initiation of treatments was accompanied by an average reduction of 40.5% [CI95% -51.6, -29.3] in the bone resorption parameters, and 22.0% [CI95% -31.9, -12.1] in the parameters of bone formation after 6-12 months. BMD was increased in both FD lesions and in the unaffected skeleton. Pain was reduced by 32.7% [CI95% -52.7, -12.6] after 6-12 months of treatment, and by 44.5% [CI95% -65.3, -23.6] after a mean 41.2 months of follow-up. The variation in pain was highly correlated to variation in bone resorption (R2 = 0.08, p < 0.0001) and formation parameters (R2 = 0.17, p < 0.0001). This study supports the overall efficacy of antiresorptive therapies in terms of reducing bone remodeling, improving bone density, and pain in FD.

Maternal iron deficiency anaemia in pregnancy: Lessons from a national audit.

We describe the management and the prevalence of iron deficiency anaemia (IDA) during pregnancy by comparison to standards. A cross-sectional national cohort study of women who had given birth six weeks prior to data collection was conducted at maternity units in the UK and Ireland. Participating centres collected data from 10 consecutive pregnant women. Analysis was descriptive to define the prevalence of IDA in pregnancy and the puerperium, and to compare the outcomes in women who had IDA with women who did not have anaemia anytime during pregnancy. Eighty-six maternity units contributed data on 860 pregnancies and births. The overall prevalence of IDA during pregnancy was 30.4% and in the puerperium 20%. Anaemic women were more likely to be from ethnic minorities, odds ratio 2.23 (1.50, 3.32). Adherence to national guidance was suboptimal, and the prevalence of anaemia in pregnancy remains very high. There is pressing need to explore barriers to early identification and effective management of iron deficiency. IDA should be considered a major public health problem in the UK.

Does Aerobic Vaginitis Have Adverse Pregnancy Outcomes? Prospective Observational Study.

Background: Aerobic vaginitis (AV) is an aberration within the balanced vaginal microbiota. Only few reports have documented the adverse pregnancy outcomes related to AV. Nonetheless, the exact role of AV in pregnancy and the potential benefit of its screening need further study. Our goal was to evaluate the association between aerobic vaginitis (AV) in late pregnancy and maternal and neonatal outcomes. Methods: In this prospective observational study, a total of 600 singleton pregnant women with intact fetal membranes at a gestational age of 34-36 weeks were recruited (one hundred women with AV and 500 pregnant women without AV). The study protocol excluded patients with other forms of vaginal infection. Pregnancy outcomes were traced and documented. The primary outcome was the association between AV and preterm labor. The current study compared the maternal and neonatal outcomes among pregnant women with and without AV in unadjusted and adjusted analyses with the odds ratio (OR) and 95% confidence interval (CI) reported. Results: There was an association between AV and with preterm birth (adjusted OR 3.06, 95% CI 1.58-5.95) and prelabor rupture of membranes (adjusted OR 6.17, 95% CI 3.24-11.7). For neonatal outcomes, AV was associated with a higher incidence of neonatal ICU admission (adjusted OR 2.19, 95% CI 1.1-4.34). Severe forms of AV significantly increased the incidence of PTB (p = 0.0014) and PROM (p = 0.0094) when compared to less severe forms of AV. Conclusion: AV is common in late pregnancy and is linked to a diversity of adversative pregnancy outcomes including preterm birth, PROM, and neonatal ICU admission. Moreover, the incidence of PTB and PROM might further increase with the severity of AV. Clinicians should pay more consideration to vaginal microbiota assessment during pregnancy.

COMBINES-CID: An Efficient Method for De Novo Engineering of Highly Specific Chemically Induced Protein Dimerization Systems.

Chemically induced dimerization (CID) systems, in which two proteins dimerize only in the presence of a small molecule ligand, offer versatile tools for small molecule sensing and actuation. However, only a handful of CID systems exist and creating one with the desired sensitivity and specificity for any given ligand is an unsolved problem. Here, we developed a combinatorial binders-enabled selection of CID (COMBINES-CID) method broadly applicable to different ligands. We demonstrated a proof-of-principle by generating nanobody-based heterodimerization systems induced by cannabidiol with high ligand selectivity. We applied the CID system to a sensitive sandwich enzyme-linked immunosorbent assay-like assay of cannabidiol in body fluids with a detection limit of ∼0.25 ng/mL. COMBINES-CID provides an efficient, cost-effective solution for expanding the biosensor toolkit for small molecule detection.

Interventionist versus expectant care for severe pre-eclampsia between 24 and 34 weeks' gestation.

BACKGROUND: Severe pre-eclampsia can cause significant mortality and morbidity for both mother and child, particularly when it occurs remote from term, between 24 and 34 weeks' gestation. The only known cure for this disease is delivery. Some obstetricians advocate early delivery to ensure that the development of serious maternal complications, such as eclampsia (fits) and kidney failure are prevented. Others prefer a more expectant approach, delaying delivery in an attempt to reduce the mortality and morbidity for the child that is associated with being born too early. OBJECTIVES: To evaluate the comparative benefits and risks of a policy of early delivery by induction of labour or by caesarean section, after sufficient time has elapsed to administer corticosteroids, and allow them to take effect; with a policy of delaying delivery (expectant care) for women with severe pre-eclampsia between 24 and 34 weeks' gestation. SEARCH METHODS: For this update, we searched Cochrane Pregnancy and Childbirth's Trials Register, ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform (ICTRP) on 27 November 2017, and reference lists of retrieved studies. SELECTION CRITERIA: Randomised trials comparing the two intervention strategies for women with early onset, severe pre-eclampsia. Trials reported in an abstract were eligible for inclusion, as were cluster-trial designs. We excluded quasi-randomised trials. DATA COLLECTION AND ANALYSIS: Three review authors independently assessed trials for inclusion and risk of bias, extracted data, and checked them for accuracy. We assessed the quality of the evidence for specified outcomes using the GRADE approach. MAIN RESULTS: We included six trials, with a total of 748 women in this review. All trials included women in whom there was no overriding indication for immediate delivery in the fetal or maternal interest. Half of the trials were at low risk of bias for methods of randomisation and allocation concealment; and four trials were at low risk for selective reporting. For most other domains, risk of bias was unclear. There were insufficient data for reliable conclusions about the comparative effects on most outcomes for the mother. Two studies reported on maternal deaths; neither study reported any deaths (two studies; 320 women; low-quality evidence). It was uncertain whether interventionist care reduced eclampsia (risk ratio (RR) 0.98, 95% confidence interval (CI) 0.06 to 15.58; two studies; 359 women) or pulmonary oedema (RR 0.45, 95% CI 0.07 to 3.00; two studies; 415 women), because the quality of the evidence for these outcomes was very low. Evidence from two studies suggested little or no clear difference between the interventionist and expectant care groups for HELLP (haemolysis, elevated liver enzymes, and low platelets) syndrome (RR 1.09, 95% CI 0.62 to 1.91; two studies; 359 women; low-quality evidence). No study reported on stroke. With the addition of data from two studies for this update, there was now evidence to suggest that interventionist care probably made little or no difference to the incidence of caesarean section (average RR 1.01, 95% CI 0.91 to 1.12; six studies; 745 women; Heterogeneity: Tau² = 0.01; I² = 63%).For the baby, there was insufficient evidence to draw reliable conclusions about the effects on perinatal deaths (RR 1.11, 95% CI 0.62 to 1.99; three studies; 343 women; low-quality evidence). Babies whose mothers had been allocated to the interventionist group had more intraventricular haemorrhage (RR 1.94, 95% CI 1.15 to 3.29; two studies; 537 women; moderate-quality evidence), more respiratory distress caused by hyaline membrane disease (RR 2.30, 95% CI 1.39 to 3.81; two studies; 133 women), required more ventilation (RR 1.50, 95% CI 1.11 to 2.02; two studies; 300 women), and were more likely to have a lower gestation at birth (mean difference (MD) -9.91 days, 95% CI -16.37 to -3.45 days; four studies; 425 women; Heterogeneity: Tau² = 31.74; I² = 76%). However, babies whose mothers had been allocated to the interventionist group were no more likely to be admitted to neonatal intensive care (average RR 1.19, 95% CI 0.89 to 1.60; three studies; 400 infants; Heterogeneity: Tau² = 0.05; I² = 84%). Babies born to mothers in the interventionist groups were more likely to have a longer stay in the neonatal intensive care unit (MD 7.38 days, 95% CI -0.45 to 15.20 days; three studies; 400 women; Heterogeneity: Tau² = 40.93, I² = 85%) and were less likely to be small-for-gestational age (RR 0.38, 95% CI 0.24 to 0.61; three studies; 400 women). There were no clear differences between the two strategies for any other outcomes. AUTHORS' CONCLUSIONS: This review suggested that an expectant approach to the management of women with severe early onset pre-eclampsia may be associated with decreased morbidity for the baby. However, this evidence was based on data from only six trials. Further large, high-quality trials are needed to confirm or refute these findings, and establish if this approach is safe for the mother.

Buffalo oocyte-secreted factors promote cumulus cells apoptosis and the rate of cGMP production but not steroidogenesis.

The objectives of this study were to investigate the effect of buffalo oocyte-secreted factors (OSFs) on cumulus cells (CCs) functions, apoptosis and cGMP generation, and whether the direct contact between oocyte and CCs is essential for oocyte-mediated regulation of CCs functions. Buffalo CCs were cultured during IVM within three groups: (a) intact cumulus-oocyte complexes (COCs), (b) CCs cocultured with denuded oocytes (DOs) (CCs + DOs) and (c) CCs monolayer cultured alone (CCsM). After 24 hr of IVM, CCs were harvested for evaluation of the relative mRNA abundance of the genes encoding gap junction (GJA1), glycolysis (PFKP and LDHA), apoptosis (CASPASE-3 and BCL-2) and steroidogenesis (ER-ß and PGR) by QRT-PCR, and CASPASE-3 proteins, using western blot. Intracellular cGMP content was also assessed by ELISA. Results showed that the relative abundance of LDHA, PFKP and BCL-2 significantly increased (p < 0.05) in COCs, whereas GJA1 and CASPASE-3 exhibited lower expression (p < 0.05) compared to CCs + DOs and CCsM groups. However, the expression levels of CASPASE-3, both mRNA and protein, were significantly (p < 0.05) downregulated in CCs + DOs compared to CCsM. There was no significant difference in the expression level of PGR and ER-ß between the groups. The intracellular content of cGMP was notably (p < 0.05) higher in COCs compared to CCs + DOs and CCsM groups. In conclusion, this study demonstrated, for the first time, that buffalo OSFs protect CCs against apoptosis and stimulate their cGMP production; however, the regulation of cumulus glycolysis and gap junction is confined to those in close contact with the oocyte. Neither OSFs from COCs nor those from DOs have any effect on CCs steroidogenesis.

How assembly matters to catalysis and thermal conductivity mediated by CuO nanoparticles.

CuO nanostructures (NSs) of different morphologies were prepared, applied as catalysts for the pyrolysis of sugarcane bagasse (PSCB), and applied for thermally-conductive nanofluids. Both size and shape of the prepared NSs ranged from 5 to 1000 nm, and from nanodots (NDs) to spindle nano-aggregates (NAs), respectively. The catalytic activity of these NSs towards the PSCB was followed up by thermogravimetric analysis (TGA), where they increased the percentage of total weight loss, and lowered the decomposition temperatures of PSCB. The Coats-Redfern kinetic model showed a decline in activation energy by 57 and 9-43 kJ mol-1 for NDs and NAs, respectively. Colloidal dispersions of CuO NDs and NAs in monoethylene glycol (MEG) were prepared with volume fractions ([Formula: see text]) of 0.01-0.04%, where thermal conductivity improved with increasing [Formula: see text]. At all values of [Formula: see text], the best enhancements were exerted by NDs. The nature of assembly impacted the catalyzed PSCB and the thermal conductivity of MEG. This behavior depends to a large extent on the NAs that expose a different fraction of crystal facets of different reactivities and surface areas, not on the constituent nanorods (NRs).

Assessment of platelets morphological changes and serum butyrylcholinesterase activity in children with diabetic ketoacidosis: a case control study.

BACKGROUND: Many studies indicated that mean platelet volume (MPV) and platelet distribution width (PDW) may be valuable in the diagnosis and management of clinical disorders; also, serum butyrylcholinesterase activity (BChE) was suggested to be linked to systemic inflammation and oxidative stress. Limited studies measured these readily available markers in children with diabetic ketoacidosis (DKA). Our objectives were to measure MPV, PDW and BChE in children with DKA; and to assess if any of these markers reflects the severity of DKA. METHODS: Our study included: 30 children with DKA (DKA group), 30 diabetic children (Non-DKA group) and 30 apparently healthy children (control group). MPV, PDW and BChE were measured in all children. Additional blood samples were withdrawn from the DKA group to assess these markers at discharge from hospital. RESULTS: MPV, PDW and BChE were significantly altered in the DKA group than the other two groups; and their levels improved significantly at discharge of the DKA group (p < 0.05). The three markers were found to equally to predict the presence of DKA, but MPV was the most suitable risk marker for DKA diagnosis (OR = 4.251, CI 95% =1.463-12.351, p = 0.003). Regarding their relation with DKA severity, they did not correlate significantly with arterial PH or serum HCO3- (p > 0.05). CONCLUSION: DKA in children is associated with changes in MPV, PDW and BChE activity, which improve after resolution of the condition. Elevated MPV can be a suitable risk marker for DKA. None of the studied markers correlated with the severity of DKA.

Recent progress and performance evaluation for polyaniline/graphene nanocomposites as supercapacitor electrodes.

Polyaniline (PANi)/graphene nanocomposites have attracted tremendous interest because of their great potential in electrochemical energy storage applications, especially supercapacitors. We herein focus on the composite synthesis, device fabrication and particularly various techniques for the improvement of electrochemical performance. It is imperative to take close control of the interface in these nanostructured composites, which thus would lead to the desired synergistic effects and cyclic stability with the efficient diffusion of electrolyte ions and electrons. Challenges and perspectives are discussed for the development of highly efficient PANi/graphene electrodes for supercapacitors.

High-performance supercapacitors using graphene/polyaniline composites deposited on kitchen sponge.

We in this study used a commercial grade kitchen sponge as the scaffold where both graphene platelets (GnPs) and polyaniline (PANi) nanorods were deposited. The high electrical conductivity of GnPs (1460 S cm(-1)) enhances the pseudo-capacitive performance of PANi grown vertically on the GnPs basal planes; the interconnected pores of the sponge provide sufficient inner surface between the GnPs/PANi composite and the electrolyte, which thus facilitates ion diffusion during charge and discharge processes. When the composite electrode was used to build a supercapacitor with two-electrode configuration, it exhibited a specific capacitance of 965.3 F g(-1) at a scan rate of 10 mV s(-1) in 1.0 M H2SO4 solution. In addition, the composite Nyquist plot showed no semicircle at high frequency corresponding to a low equivalent series resistance of 0.35 Ω. At 100 mV s(-1), the supercapacitor demonstrated an energy density of 34.5 Wh kg(-1) and a power density of 12.4 kW kg(-1) based on the total mass of the active materials on both electrodes. To demonstrate the performance, we built an array consisting of three cells connected in series, which lit up a red light emitting diode for five minutes. This simple method holds promise for high-performance yet low-cost electrodes for supercapacitors.

Newly diagnosed adult-onset Still's disease with pure red cell aplasia in pregnancy.

BACKGROUND: Adult-onset Still's disease (AOSD) is a rare inflammatory disease of unknown etiology that can present for the first time during pregnancy. Pure red cell aplasia (PRCA) is another rare condition that seldom is in association with AOSD. Herein, we have reported a newly diagnosed case with AOSD and PRCA in a previously healthy pregnant woman. CASE DESCRIPTION: A 25-year-old primigravida lady presented with fever, malaise, and arthralgia at 26 weeks of gestation. She had an extensive evaluation that led to the diagnosis of AOSD. Preliminary blood tests displayed a severe anemia with hemoglobin 5.1 g/dL, leukocytosis (total white blood cells count of 26,000 µL(-1)), normal mean corpuscular volume, normal mean corpuscular hemoglobin, normal platelet count, and a low reticulocyte count (0.2 %). The condition was diagnosed as AOSD associated with PRCA. She was treated with prednisolone and had immediate and dramatic improvement. CONCLUSION: AOSD and PRCA in pregnancy are rare conditions. The recognition of these clinical syndromes may lead to earlier diagnosis and thus prevent the expensive investigations. Both conditions have a dramatic improvement upon using corticosteroids therapy.

Evaluation of buccal bone resorption in immediate implant placement in thin versus thick buccal bone plates: An 18-month follow-up prospective cohort study.

OBJECTIVES: The current guidelines recommend that immediate implants be placed in patients with thick (>1 mm) buccal bone due to the inevitable tissue remodeling that follows tooth extraction. The aim of the current study was to investigate the effect of buccal bone thickness on bone resorption in immediate implant placement and compare two measuring techniques of the aforementioned resorption. MATERIALS: The present study was designed as a prospective nonrandomized, controlled clinical trial. A total of 30 implants were split between the two study arms, thin buccal bone and thick buccal bone. The primary outcome was to assess vertical bone changes radiographically by cone beam scans preoperatively, at 2 months and 18 months after implant placement in patients with thin and thick buccal plate. Secondary outcomes included the change in the thickness of the buccal bony plate, marginal bone loss, and pink esthetic score. RESULTS: Only 26 implants were statistically analyzed as one early failure was observed in each group. Furthermore, 2 patients of the thick group withdrew from the study. Cone beam computed tomography measurements revealed that at 2 months the vertical bone loss was 1.09 for the thin group and 0.85 for the thick group. The buccal bone plate resorption of the thin group was 0.39 mm while it was 0.52 mm for the thick group. The buccal bone plate was 1.25 mm in the thin group and 1.88 mm in the thick group. The PES did not show any significant difference with very good esthetic results. CONCLUSION: Within the limitations of the current study, the amount of buccal bone plate resorption and the subsequent thickness obtained after implantation in both groups suggest successful long-term results. The two measuring techniques have proven to be comparable and reliable in the measurement of buccal bony plate changes. https://classic. CLINICALTRIALS: gov/ct2/results?cond=&term=NCT04731545&cntry=EG&state=&city=&dist=.

Potentially Inadequate Medications in the Elderly: PRISCUS 2.0.

BACKGROUND: The term potentially inadequate medication (PIM) is used to describe substances that may be unsuitable for use inthe elderly and should be avoided. The PRISCUS list, published in 2010, was the first catalog of PIM designed for the Germandrug market to become adopted in practice. While 24% of German patients aged ≥ 65 years were prescribed at least one PIMper year in 2009, the proportion in 2019 was only 14.5%. METHODS: In a three-round Delphi process, experts from clinical practice and research evaluated whether selected substancesare PIM for the elderly. The participants were provided with dedicated literature including systematic reviews carried out for theparticular purposes of this project. RESULTS: Fifty-nine persons took part in the Delphi process and, in addition, contributed comments and therapeutic alternatives.Altogether, 187 substances were classed as PIM. One hundred thirty-three of the substances now listed were not in the originalPRISCUS list: these include some oral antidiabetics, all of the selective COX-2 inhibitors, and moderately long acting benzodiazepinessuch as oxazepam. For some other substances, e.g., proton pump inhibitors (PPI), the advisability of treatment formore than 8 weeks was considered as potentially inappropriate, as was the use of ibuprofen in doses >1200 mg/day and formore than 1 week without PPI. Risperidone for more than 6 weeks is also PIM. CONCLUSION: The new, greatly extended PRISCUS list must now be validated in epidemiological and prospective studies and itspracticability in routine daily use must be verified.

Parents' digital skills and their development in the context of the Corona pandemic.

We investigate parents' and guardians' digital skills and the extent of their development in the context of the spread of the Corona epidemic. In addition, we sought to explore the differences in digital skills between parents and their employment status, age, and responsibility in teaching children. We sought to rely on the descriptive-analytical approach and prepared a scale of eight theoretical dimensions with the participation of 250 students' Saudi parents. The application of the study was by online submission form (via Edit Submission). Our findings showed that there was a discrepancy in the performance of the sample, which was very high in the dimensions of operational skills, instrumental skills, and cognitive constructivism skills. There were also differences between the effect of computers on the instrumental skills and cognitive constructivism skills of the parents. Parents' dependence on alternative digital sources in exploring for information, formulating knowledge, manipulating it, and criticizing. The learner can reach the cognitive level in a more flexible manner, which allows him to gain learning objectives. The knowledge navigation can be developed because of different online outdoor exercises and software familiar. This requires self-organization to search for appropriate knowledge to use in the renewal of the cognitive structure.

Recognition and reprogramming of E3 ubiquitin ligase surfaces by α-helical peptides.

Molecules that induce novel interactions between proteins hold great promise for the study of biological systems and the development of therapeutics, but their discovery has been limited by the complexities of rationally designing interactions between three components, and because known binders to each protein are typically required to inform initial designs. Here, we report a general and rapid method for discovering α-helically constrained (Helicon) polypeptides that cooperatively induce the interaction between two target proteins without relying on previously known binders or an intrinsic affinity between the proteins. We show that Helicons are capable of binding every major class of E3 ubiquitin ligases, which are of great biological and therapeutic interest but remain largely intractable to targeting by small molecules. We then describe a phage-based screening method for discovering "trimerizer" Helicons, and apply it to reprogram E3s to cooperatively bind an enzyme (PPIA), a transcription factor (TEAD4), and a transcriptional coactivator (ß-catenin).

Transcerebellar diameter versus biparietal diameter for the measurement of gestational age in third trimester.

Aim: To compare the accuracy of biparietal diameter and transcerebellar diameter in measuring the gestational age during the third trimester of pregnancy. Material and methods: In this prospective observational study, 275 pregnant women with singleton pregnancy between 32 and 37 weeks gestational age were recruited from the outpatient clinics of both Helwan University Hospital and Ain Shams University Maternity Hospital, Cairo, Egypt, during the period from February 2021 to August 2021. Transcerebellar and biparietal diameters of the fetus were measured by a radiologist blinded to the women's gestational age, and compared to the gestational age acquired from a reliable date of first day of last menstrual period. Results: The gestational age calculated by first day of last menstrual period ranged from 32 to 37 weeks (34.35 ± 1.4), while estimated by transcerebellar and biparietal diameters ranged from 31 to 37 weeks (34.31 ± 1.39) and 31 to 39 weeks (34.32 ± 1.44), respectively. There was a strong positive correlation between gestational age and transcerebellar diameter (r = 0.98, p <0.001) as well as biparietal diameter (r = 0.87, p <0.001), yet a stronger correlation was with transcerebellar diameter. 93.6% of gestational age assessment by transcerebellar diameter was correct compared to only 79.9% by biparietal diameter. Conclusions: Transcerebellar diameter is a reliable single sonographic fetal biometric parameter for the assessment of gestational age in third trimester of pregnancy.

Autogenous Dentin Block of a Non-Restorable Wisdom Tooth for Localized Horizontal Ridge Augmentation: Radiographic and Histological Analysis - A Preliminary Case Report.

INTRODUCTION: Tooth roots proved in different studies clinically and radiographically to be an alternative to autogenous bone. However, the histological evaluation of the tooth block following ridge augmentation is still missing. The aim of this case report was to evaluate histologically and radiographically the effect of autogenous dentin block (DB) to restore a horizontal ridge deficiency at a single tooth gap. CASE PRESENTATION: A healthy 36-year-old female patient presented with a missing lower first molar (30), after clinical and radiographic examination, the site showed a class III defect horizontal atrophy. The procedure performed was the surgical removal of the wisdom tooth (32), shaping and fixation of a separated DB at the defect site using an osteosynthesis screw. A cone beam computed tomography was performed immediately and 6 month following the surgery. During implant placement, a core biopsy specimen was retrieved, stored and prepared for histological evaluation. The radiographic analysis showed a horizontal width gain of about 4 mm. The histologic assessment revealed cortical bone formation at the buccal and lingual aspects between the tooth and the bone. During implant placement, the core biopsy exhibited a slight separation upon removal from the grafted side, at 6 month following implant placement, the implant was successfully osteointegrated. CONCLUSION: DB was successfully used for horizontal alveolar ridge augmentation, thus allowing a prosthetically driven implant placement. More cases assessing implant survival and success are needed to confirm the results of this case report.

Extracellular ATP and its derivatives provide spatiotemporal guidance for bone adaptation to wide spectrum of physical forces.

ATP is a ubiquitous intracellular molecule critical for cellular bioenergetics. ATP is released in response to mechanical stimulation through vesicular release, small tears in cellular plasma membranes, or when cells are destroyed by traumatic forces. Extracellular ATP is degraded by ecto-ATPases to form ADP and eventually adenosine. ATP, ADP, and adenosine signal through purinergic receptors, including seven P2X ATP-gated cation channels, seven G-protein coupled P2Y receptors responsive to ATP and ADP, and four P1 receptors stimulated by adenosine. The goal of this review is to build a conceptual model of the role of different components of this complex system in coordinating cellular responses that are appropriate to the degree of mechanical stimulation, cell proximity to the location of mechanical injury, and time from the event. We propose that route and amount of ATP release depend on the scale of mechanical forces, ranging from vesicular release of small ATP boluses upon membrane deformation, to leakage of ATP through resealable plasma membrane tears, to spillage of cellular content due to destructive forces. Correspondingly, different P2 receptors responsive to ATP will be activated according to their affinity at the site of mechanical stimulation. ATP is a small molecule that readily diffuses through the environment, bringing the signal to the surrounding cells. ATP is also degraded to ADP which can stimulate a distinct set of P2 receptors. We propose that depending on the magnitude of mechanical forces and distance from the site of their application, ATP/ADP profiles will be different, allowing the relay of information about tissue level injury and proximity. Lastly, ADP is degraded to adenosine acting via its P1 receptors. The presence of large amounts of adenosine without ATP, indicates that an active source of ATP release is no longer present, initiating the transition to the recovery phase. This model consolidates the knowledge regarding the individual components of the purinergic system into a conceptual framework of choreographed responses to physical forces.