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Currently, concern about facial attractiveness is increasing, and this fact has led to orthodontics in adult patients being an increasingly demanded treatment, and with it, multi-disciplinary work. When it is caused by a vertical excess of the maxilla, the ideal solution is orthognathic surgery. However, in borderline cases and when the cause is hyperactivity of the upper lip levator muscle complex, alternative conservative solutions can be considered, such as the application of botulinum toxin A (BTX-A). Botulinum toxin is a protein produced by a bacterium and causes a reduction in the force of muscle contraction. The multi-factorial nature of the smile requires an individualized diagnosis in each patient, since there are multiple ways to treat the gummy smile (orthognathic surgery, gingivoplasty, orthodontic intrusion). In recent years, interest has grown in the simplest techniques that allow the patient to quickly return to their usual routine, such as lip replacement. However, this procedure shows recurrences in the first 6–8 post-operative weeks. The main objective of this systematic review and meta-analysis is to analyze the effectiveness of BTX-A in the treatment of gummy smile in the short term, to study its stability, and to evaluate potential complications. A thorough search of the PubMed, Scopus, Embase, Web of Science, and Cochrane databases and a grey literature search were conducted. The inclusion criteria were studies with a sample size greater than or equal to 10 patients with gingival exposure greater than 2 mm in smile, treated with BTX-A infiltration. Those patients whose exclusive etiology of their gummy smile was related to altered passive eruption, gingival thickening, or overeruption of upper incisors were excluded. In the qualitative analysis, the mean pre-treatment gingival exposure ranged between 3.5 and 7.2 mm, reaching a reduction of up to 6 mm after infiltration with botulinum toxin at 12 weeks. Although multiple muscles are involved in the facial expression, the muscles par excellence selected for blockade with BTX-A were levator labii superioris, levator labii superioris ala nasalis, and zygomaticus minor, infiltrating from 1.25 to 7.5 units per side. In the quantitative analysis, the difference in mean reduction between both groups was −2.51 mm at two weeks and −2.24 mm at three months. The benefit of BTX-A in terms of improvement of gummy smile is demonstrated, as a significant reduction in gummy smile is estimated by BTX-A therapy two weeks after its application. Its results gradually decrease over time, however, they stay satisfactory without returning to their initial values after 12 weeks. [ABSTRACT FROM AUTHOR]

Classical theory maintains that ageing evolves via energy trade‐offs between reproduction and survival leading to accumulation of unrepaired cellular damage with age. In contrast, the emerging new theory postulates that ageing evolves because of deleterious late‐life hyper‐function of reproduction‐promoting genes leading to excessive biosynthesis in late‐life. The hyper‐function theory uniquely predicts that optimizing nutrient‐sensing molecular signaling in adulthood can simultaneously postpone ageing and increase Darwinian fitness. Here, we show that reducing evolutionarily conserved insulin/IGF‐1 nutrient‐sensing signaling via daf‐2 RNA interference (RNAi) fulfils this prediction in Caenorhabditis elegans nematodes. Long‐lived daf‐2 RNAi parents showed normal fecundity as self‐fertilizing hermaphrodites and improved late‐life reproduction when mated to males. Remarkably, the offspring of daf‐2 RNAi parents had higher Darwinian fitness across three different genotypes. Thus, reduced nutrient‐sensing signaling in adulthood improves both parental longevity and offspring fitness supporting the emerging view that suboptimal gene expression in late‐life lies at the heart of ageing. [ABSTRACT FROM AUTHOR]

In this paper, we propose an application of hyperfunction theory to numerical integration. Hyperfunction theory is a generalized version of function theory where functions with singularities such as poles, discontinuities and delta impulses are expressed in terms of complex analytic functions. This feature of hyperfunction theory allows us to construct a numerical integration method for analytic functions. Theoretical error estimates show that our method converges geometrically, and numerical examples show that our method is very efficient especially for integrals with strong end-point singularities. In addition, we present an automatic integration method based on our hyperfunction method. [ABSTRACT FROM AUTHOR]

Botox has been primarily used in cosmetic treatment for lines and wrinkles on the face, but the botulinum toxin that Botox is derived from has a long history of medically therapeutic uses. For nearly 13 years, until the introduction of Botox Cosmetic in 2002, the only FDAapproved uses of Botox were for crossed eyes (strabismus) and abnormal muscle spasms of the eyelids (blepharospasm). Since then botulinum A, and the seven other forms of the botulinum toxin, have been continuously researched and tested. Botox is a neurotoxin derived from bacterium clostridium botulinm. The toxin inhibits the release of acetylcholine (ACH), a neurotransmitter responsible for the activation of muscle contraction and glandular secretion, and its administration results in reduction of tone in the injected muscle. The use of Botox is a minimally invasive procedure and is showing quite promising results in management of muscle-generated dental diseases like Temporomandibular disorders, bruxism, clenching, masseter hypertrophy and used to treat functional or esthetic dental conditions like deep nasolabial folds, radial lip lines, high lip line and black triangles between teeth. [ABSTRACT FROM AUTHOR]

Zinc oxide nanoparticles (ZnONPs) have been widely used in food storage containers and food additives in daily life. However, the impact of oral intake of ZnONPs on nervous system is extremely limited, especially on children and adolescents. In this study, four weeks old mice were treated with either vehicle or ZnONPs suspension solution at 26 mg/kg by intragastric administration for 30 days. Our results demonstrated that oral ZnONPs exposure could induce pathological changes in gut and abnormal excitement of enteric neurons. Interestingly, we found that ZnONPs caused enhancement of 5-hydroxytryptamine (5-HT) in gut by activation of its biosynthesis, transport and receptors, and subsequently resulting in increased level of 5-HT in brain via gut-brain communication by blood. Our data also showed that there were no apparent changes on the expressions of interleukin (Il)-6 , Il-1β , C–C motif chemokine ligand 2 (Ccl2), tumor necrosis factor (Tnf) in gut and zinc chelator Mt2 in gut and cortex. Meanwhile, no significant changes were observed on the expressions of tryptophan hydroxylase type 1, 5-HT receptor 3A (Htr3a) and Htr4 in hippocampus and cortex. Our study indicate that oral ZnONPs exposure causes hyperfunction of 5-HT in gut in young mice which may further spread to brain via gut-brain communication. • ZnONPs caused pathological changes and impaired endothelial tight junctions in gut. • ZnONPs caused abnormal excitement of enteric neurons and enhancement of 5-HT in gut. • ZnONPs caused activation of biosynthesis, transport and receptors of 5-HT in gut. • ZnONPs caused enhancement of 5-HT in brain via gut-brain communication by blood. [ABSTRACT FROM AUTHOR]