Mechanics and Mathematical Modeling of Class III Treatment with Orthodontic Appliances with a Movable Ramp

Treatment of class III is a current problem in orthodontics that requires constant improvement of its methods, development of new or modifications of known methods and techniques. We have developed and studied the modification of removable functionally-directing orthodontic appliances for treatment of Class III, which consists of a plastic base, vestibular arc, retaining clasps, ramp, which is connected with the base by means of two torsion springs. Its usage ensures a prolonged contact of ramp with the teeth. We studied two types of club-shaped springs (torsion springs): one spring, which create an amortization effect during the action of the ramp, but do not change its inclination angle and second one – spring that seek to increase the angle of the ramp inclination due to the disclosure of its curl

Effect of divalent cation ionophore (A 23187) on renal handling of phosphorus

Effect of divalent cation ionophore (A 23187) on renal handling of phosphorus. To evaluate the effect of an increase in intracellular calcium on renal handling of phosphorus, calcium ionophore, which facilitates passive entry of calcium into cytosol, was given i.v. to four groups of rats: group 1, animals with intact parathyroid glands; group 2, parathyroidectomized (PTX) rats; group 3, PTX animals receiving i.v. parathyroid hormone (PTH); and group 4, PTX animals pretreated with i.v. ionophore, then given i.v. PTH. During the administration of ionophore in group 1, serum calcium (Sca) decreased from 8.7 ± 0.2 (mean ±SEM) to 7.5 ± 0.2mg/100 ml (P < 0.001), fractional excretion of phosphorus (CP/CIn) decreased from 0.110 ± 0.020 to 0.019 ± 0.006 (P < 0.001), and urinary cyclic 3′, 5′-adenosine monophosphate (UcAMP) decreased from 131 ± 23 to 46 ± 16 pmoles/min (P < 0.0125). In group 2, during the administration of ionophore, Sca decreased from 6.5 ± 0.2 to 5.7 ± 0.2mg/100 ml (P < 0.001), but neither CP/CIn nor UcAMP were altered. In group 2, during the administration of ionophore, CP/Cm decreased from 0.43 ± 0.05 to 0.19 ± 0.04 (P < 0.005), UcAMP decreased from 254 ± 20 to 159 ± 11 (P < 0.001). In group 4, during combined i.v. administration of ionophore and PTH, CP/CIn was reduced from 0.19 ± 0.009 to 0.044 ± 0.012 (P < 0.005), and serum calcium was reduced from 6.5 ± 0.3 to 5.1 ± 0.3mg/100 ml (P < 0.01). These findings indicate that i.v. ionophore suppresses urinary excretion of phosphorus, only in the presence of either endogenous or exogenous PTH. The associated decrease in UcAMP suggests that this effect could be mediated through inhibition of PTH-dependent formation of cAMP, possibly resulting from the ionophore-induced increase in intracellular calcium in renal tubular cells.Effet d'un ionophore des cations divalents (A 23187) sur le comportement renal vis a vis du phosphate. Afin d'évaluer l'effet de l'augmentation du calcium intracellulaire sur le comportement rénal vis à vis du phosphore, on a donné à quatre groupes de rats un ionophore de calcium qui facilite l'entrée passive de ce cation dans le cytosol. Le groupe 1 est composé d'animaux dont les parathyroïdes sont intactes, le groupe 2 d'animaux parathyroïdectomisés (PTX), le groupe 3 d'animaux PTX recevant de l'hormone parathyroïdienne (PTH) par voie intra-veineuse et le groupe 4 d'animaux pré-traités par l'ionophore qui reçoivent de la PTH. Au cours de l'administration de l'ionophore au groupe 1, le calcium séreique (SCa) diminue de 8,7 ± 0,2 (m ±SEM) à 7,5 ± 0,2mg/100 ml (P < 0,001), l'excrétion fractionnelle du phosphore (CP/CIn) diminue de 0,110 ± 0,020 à 0,019 ± 0,006 (P < 0,001) et l'AMP cyclique urinaire (UcAMP) diminue de 131 ± 23 à 46 ± 16 pmoles/min (P < 0,0125).Dans le groupe 2, au cours de l'administration de l'ionophore, Sca diminue de 6,5 ± 0,2 a 5,7 ± 0,2 mg/100 ml (P < 0,001), mais ni CP/CIn ni UcAMP ne sont modifiés. Dans le groupe 3, au cours de l'administration de l'ionophore, CP/CIn diminue de 254 ± 20 à 159 ± 11 (P < 0,001). Dans le groupe 4, au cours de l'administration combinée d'ionophore et de PTH, CP/CIn diminue de 0,19 ± 0,009 à 0,004 ± 0,012 (P < 0,005) et Sca de 6,5 ± 0,3 à 5,1 ± 0,3 mg/100 ml (P < 0,01). Ces constatations indiquent que l'ionophore ne diminue l'excrétion urinaire de phosphate qu'en présence de PTH endogène ou exogène. La baisse associée de UcAMP suggère que cet effet peut avoir pour médiateur l'inhibition de la formation d'AMP cyclique dépendante de la PTH, conséquence de l'augmentation du calcium intracellulaire dans les cellules tubulaires rénales, induite par l'ionophore

Amino acid substitution equivalent to human chorea-acanthocytosis I2771R in yeast Vps13 protein affects its binding to phosphatidylinositol 3-phosphate

The rare human disorder chorea-acanthocytosis (ChAc) is caused by mutations in hVPS13A gene. The hVps13A protein interacts with actin and regulates the level of phosphatidylinositol 4-phosphate (PI4P) in the membranes of neuronal cells. Yeast Vps13 is involved in vacuolar protein transport and, like hVps13A, participates in PI4P metabolism. Vps13 proteins are conserved in eukaryotes, but their molecular function remains unknown. One of the mutations found in ChAc patients causes amino acids substitution I2771R which affects the localization of hVps13A in skeletal muscles. To dissect the mechanism of pathogenesis of I2771R, we created and analyzed a yeast strain carrying the equivalent mutation. Here we show that in yeast, substitution I2749R causes dysfunction of Vps13 protein in endocytosis and vacuolar transport, although the level of the protein is not affected, suggesting loss of function. We also show that Vps13, like hVps13A, influences actin cytoskeleton organization and binds actin in immunoprecipitation experiments. Vps13-I2749R binds actin, but does not function in the actin cytoskeleton organization. Moreover, we show that Vps13 binds phospholipids, especially phosphatidylinositol 3-phosphate (PI3P), via its SHR_BD and APT1 domains. Substitution I2749R attenuates this ability. Finally, the localization of Vps13-GFP is altered when cellular levels of PI3P are decreased indicating its trafficking within the endosomal membrane system. These results suggest that PI3P regulates the functioning of Vps13, both in protein trafficking and actin cytoskeleton organization. Attenuation of PI3P-binding ability in the mutant hVps13A protein may be one of the reasons for its mislocalization and disrupted function in cells of patients suffering from ChAc

pH tolerances and regulatory abilities of freshwater and euryhaline Aedine mosquito larvae

The pH regulatory abilities of two members of the mosquito tribe Aedini, known to have dramatically different saline tolerances, are investigated. The freshwater mosquito Aedes aegypti and the euryhaline Ochlerotatus taeniorhynchus tolerate very similar pH ranges. Both species complete larval development in waters ranging from pH·4 to pH·11, but naïve larvae always die in water of pH·3 or 12. Across the pH range 4–11, the hemolymph pH of O. taeniorhynchus is maintained constant while that of A. aegypti varies by 0.1 pH units. The salt composition of the water (3.5·g·l–1 sea salt, 3.5·g·l–1 NaCl, or nominally salt-free) has no effect on the range of pH tolerated by A. aegypti. In both speies, the effects of pH on larval growth and development are minor in comparison with the influence of species and sex. Acclimation of A. aegypti to pH·4 or 11 increases survival times in pH·3 or 12, respectively, and allows a small percentage of larvae to pupate successfully at these extreme pH values. Such acclimation does not compromise survival at the other pH extreme. Key words: mosquito larvae, pH regulation, pH acclimation, life history, Aedes aegypti, Ochlerotatus taeniorhynchu

Phosphatidylinositol-3-phosphate regulates response of cells to proteotoxic stress

Human Nedd4 ubiquitin ligase, or its variants, inhibit yeast cell growth by disturbing the actin cytoskeleton organization and dynamics, and lead to an increase in levels of ubiquitinated proteins. In a screen for multicopy suppressors which rescue growth of yeast cells producing Nedd4 ligase with an inactive WW4 domain (Nedd4w4), we identified a fragment of ATG2 gene encoding part of the Atg2 core autophagy protein. Expression of the Atg2-C1 fragment (aa 1074-1447) improved growth, actin cytoskeleton organization, but did not significantly change the levels of ubiquitinated proteins in these cells. The GFP-Atg2-C1 protein in Nedd4w4-producing cells primarily localized to a single defined structure adjacent to the vacuole, surrounded by an actin filament ring, containing Hsp42 and Hsp104 chaperones. This localization was not affected in several atg deletion mutants, suggesting that it might be distinct from the phagophore assembly site (PAS). However, deletion of ATG18 encoding a phosphatidylinositol-3-phosphate (PI3P)-binding protein affected the morphology of the GFP-Atg2-C1 structure while deletion of ATG14 encoding a subunit of PI3 kinase suppressed toxicity of Nedd4w4 independently of GFP-Atg2-C1. Further analysis of the Atg2-C1 revealed that it contains an APT1 domain of previously uncharacterized function. Most importantly, we showed that this domain is able to bind phosphatidylinositol phosphates, especially PI3P, which is abundant in the PAS and endosomes. Together our results suggest that human Nedd4 ubiquitinates proteins in yeast and causes proteotoxic stress and, with some Atg proteins, leads to formation of a perivacuolar structure, which may be involved in sequestration, aggregation or degradation of proteins

Three-Dimensional Ultrasonography for the Evaluation of Atherosclerotic Stenoses of the Carotid Trunk

Three-dimensional ultrasonography is a significant novelty in neurosonology as it offers the possibility of an even more successful evaluation of atherosclerotic stenoses of the carotid trunk than previous ultrasonographic investigations. In 37 patients with signs of transitory ischemic attack and in 5 patients with reversible ischemic neurologic deficit we compared the findings of three-dimensional ultrasonography of carotid arteries on the neck with those of three-dimensional CT angiography. In 20 of these patients in which carotid thrombendarterectomy had been carried out, the findings of both diagnostic methods were also compared with the angiographic and operative findings. In 2 out of the total of 42 compared findings of three-dimensional ultrasonography, three-dimensional CT angiography and angiography of the carotid trunk, we assessed a difference in the evaluation of the degree of carotid stenosis while all other findings were in accordance as regards the evaluation of the degree of stenosis and plaque analysis. Of 20 operative findings, one showed insignificant deviations from the findings of both diagnostic methods. It is our opinion that three-dimensional ultrasonography is a reliable diagnostic method in evaluating atherosclerotic stenoses of carotid arteries. Every subtotal stenosis or internal carotid artery occlusion established by three-dimensional ultrasonography must be compared with three-dimensional CT angiography or classic angiography due to the objective possibility of false ultrasonographic interpretation and the significance of carotid thrombendarterectomy

Healthcare practitioner views and experiences of patients self-monitoring blood pressure: vignette study

Background Home self-monitoring of blood pressure is widely used in primary care to assist in the diagnosis of hypertension, as well as to improve clinical outcomes and support adherence to medication. The National Institute for Health and Care Excellence (NICE) care pathways for hypertension recommend specific guidelines, although they lack detail on supporting patients to self-monitor. Aim To elicit primary care practitioners’ experiences of managing patients’ home blood pressure self-monitoring, across surgeries located in different socioeconomic areas. Design & setting A qualitative focus group study was conducted with a total of 21 primary care professionals. Method Participants were GPs and practice nurses (PNs), purposively recruited from surgeries in areas of low and high deprivation, according to the English indices of multiple deprivation. Six vignettes were developed featuring data from interviews with people who self-monitor and these were used in five focus groups. Results were thematically analysed. Results Themes derived in the thematic analysis largely reflected topics covered by the vignettes. These included: advice on purchase of a device; supporting home monitoring; mitigating patient anxiety experienced as a result of home monitoring; valuing patients’ data; and effect of socioeconomic factors. Conclusion The work provides an account of methods used by primary care practitioners in the management of home blood pressure self-monitoring, where guidance may be lacking and primary care practitioners act on their own judgement. Findings complement recent policy documentation, which recognises the need to adopt new ways of working to empower patients (for example, additional support from healthcare assistants), but lacks detail on how this should be done

Caspase-11 regulates the tumour suppressor function of STAT1 in a murine model of colitis-associated carcinogenesis

Murine inflammatory caspase-11 has an important role in intestinal epithelial inflammation and barrier function. Activation of the non-canonical inflammasome, mediated by caspase-11, serves as a regulatory pathway for the production of the proinflammatory cytokines IL-1β and IL-18, and has a key role in pyroptotic cell death. We have previously demonstrated a protective role for caspase-11 during dextran sulphate sodium (DSS)-induced colitis, however the importance of caspase-11 during colorectal tumour development remains unclear. Here, we show that Casp11−/− mice are highly susceptible to the azoxymethane (AOM)-DSS model of colitis-associated cancer (CAC), compared to their wild type (WT) littermates. We show that deficient IL-18 production occurs at initial inflammation stages of disease, and that IL-1β production is more significantly impaired in Casp11−/− colons during established CAC. We identify defective STAT1 activation in Casp11−/− colons during disease progression, and show that IL-1β signalling induces caspase-11 expression and STAT1 activation in primary murine macrophages and intestinal epithelial cells. These findings uncover an anti-tumour role for the caspase-11 and the non-canonical inflammasome during CAC, and suggest a critical role for caspase-11, linking IL-1β and STAT1 signalling pathways

The origin of paramagnetic magnetization in field-cooled YBa2Cu3O7 films

Temperature dependences of the magnetic moment have been measured in YBa_2Cu_3O_{7-\delta} thin films over a wide magnetic field range (5 <= H <= 10^4 Oe). In these films a paramagnetic signal known as the paramagnetic Meissner effect has been observed. The experimental data in the films, which have strong pinning and high critical current densities (J_c ~ 2 \times 10^6 A/cm^2 at 77 K), are quantitatively shown to be highly consistent with the theoretical model proposed by Koshelev and Larkin [Phys. Rev. B 52, 13559 (1995)]. This finding indicates that the origin of the paramagnetic effect is ultimately associated with nucleation and inhomogeneous spatial redistribution of magnetic vortices in a sample which is cooled down in a magnetic field. It is also shown that the distribution of vortices is extremely sensitive to the interplay of film properties and the real experimental conditions of the measurements.Comment: RevTex, 8 figure

Leprosy-an unusual cause of a suspicious nodule on mammography

A routine mammogram identified changes thought to be due to a lymph node, which was confirmed on biopsy. The lymph node was infiltrated with macrophages and showed fragmented acid-fast bacilli. The patient had been treated for leprosy some years before and was still taking thalidomide for erythema nodosum leprosum. Leprosy-associated lymphadenopathy may be identified on routine breast screening