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Objective: To evaluate tooth displacement and periodontal stress generated by the dual action vertical intra-arch technique (DAVIT) for open-bite correction using three-dimensional finite element analysis., Methods: A three-dimensional model of the maxilla was created by modeling the cortical bone, cancellous bone, periodontal ligament, and teeth from the second molar to the central incisor of a hemiarch. All orthodontic devices were designed using specific software to reproduce their morpho-dimensional characteristics, and their physical properties were determined using Young's modulus and Poisson's coefficient of each material. A linear static simulation was performed to analyze the tooth displacements (mm) and maximum stresses (Mpa) induced in the periodontal ligament by the posterior intrusion and anterior extrusion forces generated by the DAVIT., Results: The first and second molars showed the greatest intrusion, whereas the canines and lateral incisors showed the greatest extrusion displacement. A neutral zone of displacement corresponding to the fulcrum of occlusal plane rotation was observed in the premolar region. Buccal tipping of the molars and lingual tipping of the anterior teeth occurred with intrusion and extrusion, respectively. Posterior intrusion generated compressive stress at the apex of the buccal roots and furcation of the molars, while anterior extrusion generated tensile stress at the apex and apical third of the palatal root surface of the incisors and canines., Conclusions: DAVIT mechanics produced a set of beneficial effects for open-bite correction, including molar intrusion, extrusion and palatal tipping of the anterior teeth, and occlusal plane rotation with posterior teeth uprighting.

The non-muscle actomyosin cytoskeleton generates contractile force through the dynamic rearrangement of its constituent parts. Actomyosin rings are a specialization of the non-muscle actomyosin cytoskeleton that drive cell shape changes during division, wound healing, and other events. Contractile rings throughout phylogeny and in a range of cellular contexts are built from conserved components including non-muscle myosin II (NMMII), actin filaments (F-actin), and crosslinking proteins. However, it is unknown whether diverse actomyosin rings close via a single unifying mechanism. To explore how contractile forces are generated by actomyosin rings, we studied three instances of ring closure within the common cytoplasm of the C. elegans oogenic germline: mitotic cytokinesis of germline stem cells (GSCs), apoptosis of meiotic compartments, and cellularization of oocytes. We found that each ring type closed with unique kinetics, protein density and abundance dynamics. These measurements suggested that the mechanism of contractile force generation varied across the subcellular contexts. Next, we formulated a physical model that related the forces generated by filament-filament interactions to the material properties of these rings that dictate the kinetics of their closure. Using this framework, we related the density of conserved cytoskeletal proteins anillin and NMMII to the kinematics of ring closure. We fitted model rings to in situ measurements to estimate parameters that are currently experimentally inaccessible, such as the asymmetric distribution of protein along the length of F-actin, which occurs naturally due to differences in the dimensions of the crosslinker and NMMII filaments. Our work predicted that the role of NMMII varies across these ring types, due in part to its distribution along F-actin and motoring. Our model also predicted that the degree of contractility and the impact of ring material properties on contractility differs among ring types.

A complex crystallization behavior was observed for the alternating copolymer DMDS- alt -DVE synthesized via thiol-ene step-growth polymerization. Understanding the underlying complex crystallization processes of such innovative polythioethers is critical for their application, for example, in polymer coating technologies. These alternating copolymers have polymorphic traits, resulting in different phases that may display distinct crystalline structures. The copolymer DMDS- alt -DVE was studied in an earlier work, where only two crystalline phases were reported: a low melting, L - T m , and high melting, H - T m phase. Remarkably, the H - T m form was only achieved by the previous formation and melting of the L - T m form. We applied calorimetric techniques encompassing seven orders of magnitude in scanning rates to further explore this complex polymorphic behavior. Most importantly, by rapidly quenching the sample to temperatures well below room temperature, we detected an additional polymorphic form (characterized by a very low melting phase, denoted VL - T m ). Moreover, through tailored thermal protocols, we successfully produced samples containing only one, two, or all three polymorphs, providing insights into their interrelationships. Understanding polymorphism, crystallization, and the resulting morphological differences can have significant implications and potential impact on mechanical resistance and barrier properties., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

Objective: To evaluate the null hypothesis that there is no difference in a set of clinical predictors of potentially impacted canines between low-risk patients with and without displaced canines., Methods: The normal canine position group consisted of 30 patients with 60 normally erupting canines ranked in sector I (age, 9.30 ± 0.94 years). The displaced canine group comprised 30 patients with 41 potentially impacted canines ranked in sectors II to IV (age, 9.46 ± 0.78 years). Maxillary lateral incisor crown angulation, inclination, rotation, width, height, and shape, as well as palatal depth, arch length, width, and perimeter composed a set of clinical predictors, which were evaluated on digital dental casts. Statistical analyses consisted of group comparisons and variable correlations ( p < 0.05)., Results: There was a significant association between sex and mesially displaced canines. Unilateral canine displacement was more prevalent than bilateral displacement. The crown of the maxillary lateral incisors was significantly angulated more mesially and rotated mesiolabially in low-risk patients with displaced canines, who also had a shallower palate and shorter anterior dental arch length. Lateral incisor crown angulation and rotation, as well as palatal depth and arch length, were significantly correlated with the canine displacement severity., Conclusions: The null hypothesis was rejected. Maxillary lateral incisor angulation inconsistent with the "ugly duckling" stage as well as a shallow palate and short arch length are clinical predictors that can significantly contribute to the early screening of ectopic canines in low-risk patients.

A photocatalytic thiol-ene aqueous emulsion polymerization under visible-light is described to prepare linear semicrystalline latexes using 2,2'-dimercaptodiethyl sulfide as dithiol and various dienes. The procedure involves low irradiance (3 mW cm -2 ), LED irradiation source, eosin-Y disodium as organocatalyst, low catalyst loading (<0.05% mol), and short reaction time scales (<1 h). The resulting latexes have molecular weights of about 10 kg mol -1 , average diameters of 100 nm, and a linear structure consisting only of thioether repeating units. Electron-transfer reaction from a thiol to the triplet excited state of the photocatalyst is suggested as the primary step of the mechanism (type I), whereas oxidation by singlet oxygen generated by energy transfer has a negligible effect (type II). Only polymers prepared with aliphatic dienes such as diallyl adipate or di(ethylene glycol) divinyl ether exhibit a high crystallization tendency as revealed by differential scanning calorimetry, polarized optical microscopy, and X-ray diffraction. Ordering and crystallization are driven by molecular packing of poly(thioether) chains combining structural regularity, compactness, and flexibility., (© 2021 Wiley-VCH GmbH.)

We synthesized a directed library of compounds to explore the structure-activity relationships of peroxisome proliferator-activated receptor δ (PPARδ) activation relative to mesenchymal stem cell (MSC) osteogenesis. Our scaffold used para-substituted cinnamic acids as a polar headgroup, a heteroatom and heterocycle core connecting units, and substituted phenyl groups for the lipophilic tail. Compounds were screened for their ability to increase osteogenesis in MSCs, and the most promising were examined for subunit specificity using a quantitative PPAR transactivation assay. Six compounds were selected for in vivo studies in an ovariectomized mouse model of human postmenopausal osteoporosis. Four compounds improved bone density in vivo, with two ( 12d and 31a ) having activity comparable to that of GW0742, a well-studied PPARδ-selective agonist. 31a (2-methyl-4-[ N -methyl- N -[5-methylene-4-methyl-2-[4-(trifluoromethyl)phenyl]thiazole]]aminocinnamic acid) had the highest selectivity for PPARδ compared to other subtypes, its selectivity far exceeding that of GW0742. Our results confirm that PPARδ is a new drug target for possible treatment of osteoporosis via in situ manipulation of MSCs.

Changes in surface energy and electrical conductivity of polyimide (PI)-based nanocomposite films filled with carbon nanotubes (CNTs) induced by UV exposure are gaining considerable interest in microelectronic, aeronautical, and aerospace applications. However, the underlying mechanism of PI photochemistry and oxidation reactions induced by UV irradiation upon the surface in the presence of CNTs is still not clear. Here, we probed the interplay between CNTs and PIs under UV exposure in the surface properties of CNT/PI nanocomposite films. Changes in contact angles and surface electrical conductivity at the surface of CNT/PI nanocomposite films after UV exposure were measured. The unpaired electron intensity of free radicals generated by UV exposure was monitored by electron paramagnetic resonance. Our study indicates that the covalent interactions between CNTs and radicals generated by UV irradiation on the PI surfaces tailor the surface energy and surface conductivity through anchoring radicals on CNTs. Surprisingly, adding CNTs into PI films exposed to UV leads to antagonistic contributions of dispersion and polar components to the surface energy. The surface electrical conductivity of the CNT/PI nanocomposite films has been improved due to an enhanced hopping behavior with dense π-conjugated CNT sites. To explain the observed changes in surface energy and surface conductivity of CNT/PI nanocomposite films induced by UV exposure, a qualitative model was put forward describing the covalent interactions between UV-induced PI free radicals and CNTs, which govern the chemical nature of surface components. This study is helpful for characterizing and optimizing nanocomposite surface properties by tuning the covalent interactions between components at the nanoscale.

Glass is one of the most relevant high-performance materials that has the benefit of a favorable environmental footprint compared with that of other commodity materials. Despite the advantageous properties of glasses, polymers are often favored because they can be processed using scalable industrial replication techniques like injection molding (IM). Glasses are generally processed through melting, which is both energy intensive and technologically challenging. We present a process for glassworks using high-throughput IM of an amorphous silicon dioxide nanocomposite that combines established process technologies and low-energy sintering. We produce highly transparent glass using classical IM and sintering, allowing for a potentially substantial reduction in energy consumption. Our strategy merges polymer and glass processing, with substantial implications for glass utilization., (Copyright © 2021 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)

Expanded polyglutamine (polyQ) sequences cause numerous neurodegenerative diseases which are accompanied by the formation of polyQ fibrils. The unique role of glutamines in the aggregation onset is undoubtedly accepted and a lot structural data of the fibrils have been acquired, however side-chain specific structural dynamics inducing oligomerization are not well understood yet. To analyze spectroscopically the nucleation process, we designed various template-assisted glutamine-rich β-hairpin monomers mimicking the structural motif of a polyQ fibril. In a top-down strategy, we use a template which forms a well-defined stable hairpin in solution, insert polyQ-rich sequences into each strand and monitor the effects of individual glutamines by NMR, CD and IR spectroscopic approaches. The design was further advanced by alternating glutamines with other amino acids (T, W, E, K), thereby enhancing the solubility and increasing the number of cross-strand interacting glutamine side chains. Our spectroscopic studies reveal a decreasing hairpin stability with increased glutamine content and demonstrate the enormous impact of only a few glutamines - far below the disease threshold - to destabilize structure. Furthermore, we could access sub-ms conformational dynamics of monomeric polyQ-rich peptides by laser-excited temperature-jump IR spectroscopy. Both, the increased number of interacting glutamines and higher concentrations are key parameters to induce oligomerization. Concentration-dependent time-resolved IR measurements indicate an additional slower kinetic phase upon oligomer formation. The here presented peptide models enable spectroscopic molecular analyses to distinguish between monomer and oligomer dynamics in the early steps of polyQ fibril formation and in a side-chain specific manner., (This journal is © The Royal Society of Chemistry 2021.)

Background: Gastroenteritis (GE) and respiratory tract infection (RTI) outbreaks are a significant issue in nursing homes. This study aimed to describe GE and RTI outbreaks with infection and all-cause lethality rates according to the individual characteristics of nursing home residents., Methods: Clinical and virological surveillance were conducted (2007 to 2018). Virus stratifications for the analysis were: outbreaks with positive norovirus or influenza identifications (respectively NoV+ or Flu+), episodes with no NoV or influenza identification or testing (respectively NoV- or Flu-). Associations between individual variables (sex, age, length of stay (LOS), autonomy status) and infection and lethality rates were tested with univariate and Mantel-Haenszel (MH) methods., Results: 61 GE outbreaks and 76 RTI oubreaks (total 137 outbreaks) were recorded involving respectively 4309 and 5862 residents. In univariate analysis, higher infection rates and age were associated in NoV+, NoV-, and Flu+ contexts, and lower infection rates were associated with longer stays (NoV+ and NoV-). In MH stratified analysis (virus, sex (female/male)) adjusted for LOS (<4 or ≥4 years), the odds of being infected remained significant among older residents (≥86 years): NoV+/male (Odds ratio (ORMH): 1.64, 95% confidence interval (CI): 1.16-2.30) and Flu+/female and male (respectively ORMH: 1.50, CI: 1.27-1.79 and 1.73, CI: 1.28-2.33). In univariate analysis, lower autonomy status (NoV+, Flu+ and Flu-) and increased age (Flu+) were associated with higher lethality. In MH adjusted analysis, significant ORage adjusted for autonomy was: Flu+/ ≥86 years compared with <86 years, 1.97 (1.19-3.25) and ORautonomy adjusted for age for the more autonomous group (compared with the less autonomous group) was: Flu+, 0.41 (0.24-0.69); Flu-, 0.42 (0.20, 0.90)., Conclusion: The residents of nursing homes are increasingly elderly and dependent. The specific infection and lethality risks according to these two factors indicate that surveillance and infection control measures are essential and of high priority., Competing Interests: The authors have declared that no competing interests exist.

Widespread environmental impacts of frequent drought episodes in Brazil have resulted in several drought-related diagnostics studies. However, the potential of many "opportunistic sensors", such as the Global Positioning System (GPS), has not yet been considered in hydrological hazard monitoring in Brazil. In this study, the response of the Earth's crust to Brazil's 2012-2015 drought event in different structural provinces is analyzed by comparing GPS-observed vertical crustal deformations (VCDs) with the terrestrial water storage (TWS) derived from the Gravity Recovery and Climate Experiment (GRACE). The results indicate that there is no spatial correlation between annual amplitudes of the TWS and VCDs in different structural provinces apart from the purely elastic response of the crust to TWS dynamics, at almost all the 39 GPS stations that were analyzed. However, approximately 15% of the monitoring stations show that VCD leads TWS with a phase lag of 2-4 months. Errors associated with VCD and TWS are within the accepted range for space geodetic techniques (i.e., GPS and GRACE) and despite the need for further investigation, the phase lead seems to be associated with rainfall, which impacts the TWS through the hydrographs. Overall, the GPS-based drought index (DI VCD ) reflects the water depletion in many regions of Brazil, which agrees with the GRACE-based DI TWS in terms of the Spearman correlation coefficient (ranging from 0.4 to 0.9) in the Amazon, Tocantins, La Plata, and São Francisco river basins. This agreement confirms the drought persistence during the study period and that DI VCD can be used to monitor hydrological droughts. In regions in which DI TWS sufficiently agrees with DI VCD (48% of the sites), near real-time drought monitoring is feasible. This could be useful in the optimization of models for the forward prediction of drought events in other regions worldwide, where GPS vertical displacements strongly correlate with hydrological GRACE signals., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Objectives: Viruses are recognized as important agents of gastroenteritis outbreaks in institutions caring for dependent people. We aimed to define norovirus (NoV) and rotavirus (RV) immunochromatographic tests (ICT) and reverse transcription-polymerase chain reaction (RT-PCR) used in gastroenteritis investigations., Methods: Fourteen sites were monitored from 2010 to 2015, with 360 laboratory investigations. Twenty-two outbreaks and 44 sporadic case patients were investigated with ICTs (114 NoVs and 80 RVs) and RT-PCRs (114 NoVs and 52 RVs)., Results: ICTs were useful during outbreaks (identification of NoVs and RVs in respectively 76.5% and 75.0% of episodes) despite the NoV sensitivity limit (55.1%) and the four RV false positive results observed for 10 samples. Given the NoV ICT performance and the observed variations of the NoV and RV prevalence (between 20.0% and 5.0%), ICTs are not appropriate to identify sporadic gastroenteritis case patients. Positive predictive values <60.0% were observed when the prevalence of RV and NoV was low (<5.0%). NoV and RV RT-PCR indications are sporadic gastroenteritis case patients, negative NoV and RV ICT during outbreaks, control of positive RV ICT in cases of suspected NoV and RV co-circulation, patients with long symptom duration, and NoV genogroup and genotype identifications (infection control and epidemiological surveillance). Inclusion of patients with specific clinical symptoms is recommended irrespective of the technique., Conclusion: On the basis of the ICT limits identified in this work, RT-PCR development seems essential to improve viral gastroenteritis investigations in institutions caring for dependent people., (Copyright © 2017 Elsevier Masson SAS. All rights reserved.)

Early events of protein folding can be studied with fast perturbation techniques triggering non-equilibrium relaxation dynamics. A nanosecond laser-excited pH-jump or temperature-jump (T-jump) was applied to initiate helix folding or unfolding of poly-l-glutamic acid (PGA). PGA is a homopolypeptide with titratable carboxyl side-chains whose protonation degree determines the PGA conformation. A pH-jump was realized by the photochemical release of protons and induces PGA folding due to protonation of the side-chains. Otherwise, the helical conformation can be unfolded by a T-jump. We operated under conditions where PGA does not aggregate and temperature and pH are the regulatory properties of its conformation. The experiments were performed in such a manner that the folding/unfolding jump proceeded to the same PGA conformation. We quantified the increase/decrease in helicity induced by the pH-/T-jump and demonstrated that the T-jump results in a relatively small change in helical content in contrast to the pH-jump. This is caused by the strong pH-dependence of the PGA conformation. The conformational changes were detected by time-resolved single wavelength IR-spectroscopy using quantum cascade lasers (QCL). We could independently observe the kinetics for α-helix folding and unfolding in PGA by using different perturbation techniques and demonstrate the high sensitivity of time-resolved IR-spectroscopy to study protein folding mechanisms., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Cafe-au-lait maculae (CALM) are frequently observed in humans, and usually are present as a solitary spot. Multiple CALMs are present in a smaller fraction of the population and are usually associated with other congenital anomalies as part of many syndromes. Most of these syndromes carry an increased risk of cancer development. Previous studies have indicated that minor congenital anomalies may be more prevalent in children with cancer. We investigated the prevalence of CALMs in two samples of Brazilian patients with childhood solid tumors, totaling 307 individuals. Additionally, 176 school children without diagnosis of cancer, or of a cancer predisposing syndrome, were investigated for the presence of CALMs. The prevalence of solitary CALM was similar in both study groups (18% and 19%) and also in the group of children without cancer. Multiple CALMs were more frequently observed in one of the study groups (Z = 2.1). However, when both groups were analyzed together, the significance disappeared (Z = 1.5). The additional morphological abnormalities in children with multiple CALMs were analyzed and compared to the findings observed in the literature. The nosologic entities associated with CALMs are reviewed.

We report on near theoretical yield production of cellulose I nanocrystals (CNCs) using a two-step hydrolysis with the mildly acidic ionic liquid (IL) 1-butyl-3-methylimidazolium hydrogen sulfate ([Bmim]HSO4) in aqueous solution from common cellulosic sources. Two successive Taguchi experimental plans were performed to evaluate the impact of selected reaction parameters (T, t, H2O:IL ratio) and their interactions on the CNCs' yield from bleached softwood kraft pulp (SWP), bleached hardwood kraft pulp (HWP) and microcrystalline cellulose (MCC). With these experimental plans, the molar yield for extraction of nanocrystals was optimized to near theoretical levels, reaching 57.7±3.0%, 57.0±2.0%, and 75.6±3.0%, for SWP, HWP and MCC, respectively. The reaction yields corresponded to a relative crystalline region recovery of 84.1±5.3%, 71.7±1.3%, 76.0±2.0% from SWP, HWP and MCC, respectively. The collected nanocrystals exhibited high aspect ratios (36-43), negligible sulfur content (0.02-0.21%) and high solvent dispersibility in comparison to those obtained with the traditional sulfuric acid method. Additionally these near theoretical yields were achieved for mild reaction conditions with the combined severity factor of 2 and 3 for MCC and pulp, respectively. Overall this two-stage IL-mediated preparation of nanocrystals combines the advantages of achieving high product quality, high reaction yields and mild conditions., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

The photophysical properties of a phenyl-substituted poly(thiophene), poly(3-(2,5-dioctylphenyl)thiophene) (PDOPT), were studied as a function of polarization and degree of orientation of the crystalline structure. Under well-chosen controlled conditions, large-sized spherulitic crystals of PDOPT were successfully prepared from the melt. From polarized optical microscopy and X-ray diffraction, the molecular orientation of PDOPT within the spherulite was determined, indicating that the fastest growth direction of the spherulite was the a -axis. This implied that crystallization of PDOPT was directed by the packing of the side chains rather than the backbones, which are significantly separated. As the crystalline lamellae were all radially oriented, the local absorbance strongly depended on the polarization of the incoming light. Compared to randomly oriented crystals in a quenched and thus rapidly crystallized sample, PDOPT spherulites displayed red-shifted absorption and emission spectra, combined with a reduced photoluminescence quantum yield. Even for these markedly separated polymer backbones (1.47 nm), the reduced photoluminescence suggests an enhancement of interchain interactions of highly ordered bulky substituted polythiophene induced by crystallization.

Aims: Constitutive genetic factors are believed to predispose to cancer in children. This study investigated the role of rare germline copy number variations (CNVs) in pediatric cancer predisposition., Patients & Methods: A total of 54 patients who developed cancer in infancy were screened by array-CGH for germline CNVs., Results: In total, 12 rare CNVs were detected, including a Xq27.2 triplication, and two >1.8 Mb deletions: one of them at 13q31, containing only RNA genes, and another at 3q26.33-q27.1, in a patient with congenital malformations. Detected rare CNVs are significantly larger than those identified in controls, and encompass genes never implicated in cancer predisposition., Conclusion: Our results suggest that constitutive CNVs contribute to the etiology of pediatric neoplasms, revealing new candidate genes for tumorigenesis.

Supernumerary marker chromosomes (sSMC) may or may not be associated with an abnormal phenotype, depending on the presence of euchromatin, on their chromosomal origin and whether they are inherited. Over 80% of sSMCs are derived from acrocentric chromosomes and half of them include the short arm of chromosome 15. Generally, they appear as bisatellited isodicentric marker chromosomes, most of them are symmetric. These chromosomes are normally originated de novo and are associated with mild to severe intellectual disability but not with physical abnormalities. We report on a patient with an SMC studied using classical and molecular cytogenetic procedures (G and C banding, NOR staining, painting and centromeric fluorescent in situ hybridization (FISH), BAC-FISH, and SKY). The MLPA technique and DNA polymorphic markers were used in order to identify its parental origin. The marker chromosome, monosatellited and monocentric, was found to be derived from a maternal chromosome 15 and was defined as 15pter-q21.2. This is the report of the largest de novo monosatellited 15q marker chromosome ever published presenting detailed cytogenetic and clinical data. It was associated with a phenotype including cardiac defect, absence of septum pellucidum, and dysplasia of the corpus callosum., ((c) 2010 Wiley-Liss, Inc.)

Gómez-López-Hernández (GLH) syndrome or cerebello-trigeminal dysplasia is a neurocutaneous syndrome whose etiology is unknown at the present time. We report two additional Brazilian patients, including the oldest one known to date (age 29). Here, we review the expanded phenotype in four patients with new clinical, psychiatric, radiological, and molecular investigations. One patient may have hypomania within the bipolar spectrum disorder with onset in childhood and adolescence. Primary growth hormone (GH) deficiency was ruled out in all patients, although one of them might have developed secondary GH deficiency due to partial hypopituitarism following severe hydrocephalus. Brain magnetic resonance angiography disclosed no azygous anterior cerebral artery (ACA) but only normal variants. Molecular analysis of the lysosomal acid phosphatase gene (ACP2) was performed, but no pathogenic mutations were identified. We present an overview of the phenotypic features of all patients described to date. There are currently 12 unrelated patients reported in the literature, 5 of whom are Brazilian. We discuss new molecular insights and speculate about the pathogenesis of GLH syndrome., ((c) 2008 Wiley-Liss, Inc.)

The primary aim of this investigation was to determine the long term overall accuracy of an irradiation position of Gamma Knife systems. The mechanical accuracy of the system as well as the overall accuracy of an irradiation position was examined by irradiating radiosensitive films. To measure the mechanical accuracy, the GafChromic film was fixed by a special tool at the unit center point (UCP). For overall accuracy the film was mounted inside a phantom at a target position given by a two-dimensional cross. Its position was determined by CT or MRI scans, a treatment was planned to hit this target by use of the standard planning software and the radiation was finally delivered. This procedure is named "system test" according to DIN 6875-1 and is equivalent to a treatment simulation. The used GafChromic films were evaluated by high resolution densitometric measurements. The Munich Gamma Knife UCP coincided within x; y; z: -0.014 +/- 0.09 mm; 0.013 +/- 0.09 mm; -0.002 +/- 0.06 mm (mean +/- SD) to the center of dose distribution. There was no trend in the measured data observed over more than ten years. All measured data were within a sphere of 0.2 mm radius. When basing the target definition in the system test on MRI scans, we obtained an overall accuracy of an irradiation position in the x direction of 0.21 +/- 0.32 mm and in the y direction 0.15 +/- 0.26 mm (mean +/- SD). When a CT-based target definition was used, we measured distances in x direction 0.06 +/- 0.09 mm and in y direction 0.04 +/- 0.09 mm (mean +/- SD), respectively. These results were compared with those obtained with a Gamma Knife equipped with an automatic positioning system (APS) by use of a different phantom. This phantom was found to be slightly less accurate due to its mechanical construction and the soft fixation into the frame. The phantom related position deviation was found to be about +/- 0.2 mm, and therefore the measured accuracy of the APS Gamma Knife was evidently less precise by additional +/- 0.2 mm. These measurements demonstrate that an irradiation position defined by a CT scan can be hit within the intrinsic system precision. In radiosurgery with the Gamma Knife, a fixation with the Leksell stereotactic frame is applied. As this frame is considered to add no further uncertainties due to patient movements, the measured accuracy applies to a real patient treatment situation. The major contribution to the overall accuracy of an irradiation position is given by the MRI scans.

Patients with 1q duplication have demonstrated a wide range of multiple congenital abnormalities. Alterations involving this chromosomal region have being described in hematopoietic malignancies and a series of candidate genes that may be associated with neoplasias have been mapped in this region. We describe a case of partial trisomy 1q "syndrome" and acute monocytic leukemia. Cytogenetic study of the bone marrow cells by GTG-banding and spectral karyotyping (SKY) showed dup(1)(q23q44) in all cells analyzed. The dismorphological features with the dup(1q) suggest a constitutional chromosome alteration and the first, in our knowledge, association of a trisomy 1q "syndrome" with AML.

Objective: To compare embryo implantation in Wistar rats submitted to ovarian stimulation using recombinant FSH (rFSH) with cetrorelix acetate or leuprolide acetate., Design: Experimental study., Setting: Faculty of medicine animal facility., Patient(s): Fifty-six female Wistar rats with normal estrus cycles and 30 male., Intervention(s): Ovarian stimulation and laparotomy (by the day 13 of gestation)., Main Outcome Measure(s): Embryo implantation., Result(s): The female rats were subdivided into four groups: group 1, medicated with rFSH, hCG, and cetrorelix acetate; group 2, medicated with rFSH, hCG, and leuprolide acetate; group 3, medicated with rFSH and hCG; and group 4, in which only saline solution was administered. The female rats were mated with fertile male rats on the day of hCG administration with copulation confirmed through cytologic vaginal analysis. The females were killed on the 13th day of gestation. After laparotomy, comparison and identification was done regarding the numbers of corpora lutea and embryo implantations and gestation rates. Group 1 presented lower numbers of corpora lutea and embryo implantations in comparison to the other groups (P<.05). A difference was not found in the gestation rates between the groups., Conclusion(s): The number of embryo implantations in Wistar rats medicated with rFSH and cetrorelix acetate is lower than that of rats medicated with rFSH and leuprolide acetate.

Observations of a sample of poly(ethylene-co-octene)in a polarizing optical microscope reveal peculiarities in its crystallization behavior. When cooled from the melt to a fixed crystallization temperature, at first a structure of diffuse appearance with variations on the length scale of micrometers forms rapidly. The transformation into the final semi-crystalline state then proceeds in two ways, by a continuous change of the inner structure of microm-sized objects and by the growth of spherulites. Time dependent small angle and wide angle X-ray scattering experiments corroborate the occurrence of the two crystallization mechanisms. Atomic force microscopy indicates that the change of the inner structure of the preformed objects is due to an in-filling of crystallites.

Dilatometric and X-ray scattering experiments of the crystallization kinetics of a sample of poly(ethylene-co-octene) show pronounced melt memory effects, i.e., the shapes of isotherms and characteristic times vary systematically with the temperature of the melt prior to cooling to the crystallization temperature. The temperature range of the effect is limited; crystallization kinetics remains constant below a melt temperature T(m)l and above a melt temperature T(m)h and varies only in-between. Analysis shows that the melt memory effect is caused by a variation of the characteristic time of a first order crystallization process. The process can be assigned to the in-filling of crystallites into objects of a previously generated precursor structure.

Background: Single dose irradiation techniques require methods of quality assurance of high precision. The complete operational sequence of a treatment from imaging over irradiation planning up to the patient irradiation has to be controlled and verified in a phantom (Figure 2). These demands receive special topicality by the E-DIN 6875-1 [38], which will appear soon., Material and Methods: A quality assurance package was developed to meet the requirements of the E-DIN 6875-1 [38]. It consists of versatile usable precision phantom (Figure 1), a dose measuring system for the tissue equivalent radiochromic film GAFCHROMIC trade mark type MD 55 II using a high-quality scanner, and a software for standardized test routines (Figures 2 to 4). Correction routines for film fog, darkening, temperature effect as well as for film inhomogeneities (double exposure technology) are implemented., Results: The measuring system permits routine dosimetry with inaccuracies typically < 5%, for the double exposure procedure typically < 3% with local dissolutions of approx. 1/100 mm in film plane, perpendicularly to it the film stack density and the film thickness (0.3 mm) are determining. The measuring system is designed to simulate the complete three-dimensional treatment of a patient (Figure 4)., Conclusions: The procedure achieves a high quality standard for all steps in radiosurgery. The simple handling permits the employment for the daily routine (according to E-DIN 6875-1 [38]), in addition, for the modelling of complicated 3-d of scattering conditions, e. g. close to risk structures.

Melting points in mixtures of a crystallizable polymer with a low-molar-mass diluent depend on both, the diluent fraction and the crystal thickness. A differentiation of the two factors can be achieved by temperature-dependent SAXS experiments. A corresponding study, complemented by DSC, dilatometry, microscopy and AFM-imaging, was carried out for mixtures of a poly(ethylene-co-octene) with n-C16H34, c-C16H32 and methyl-anthracene, respectively. All diluents lead for a constant crystal thickness to melting point depressions in agreement with Raoult's law. On the other hand, the effect of the diluents on the thickness of the crystals formed at a fixed crystallization temperature varies. While in the presence of the two alkanes thicker crystals form, no effect arises for the methyl-anthracene--as was previously found for the octene-co-units. We consider these observations as a further support for our view that polymer crystallization follows a multi-stage route which includes a passage through an intermediate mesomorphic phase. Under such conditions crystal thicknesses would only be affected if the diluent is still present in the mesomorphic phase and stay invariant if the diluent molecules are already rejected when this intermediate phase forms.

The Gamma Knife is used as a stereotactic tool for the conformal treatment of very small, complex-shape cranial lesions. The combination of planning software and treatment equipment enables a highly-precise conformal dose distribution and positioning. The purpose of the present study was to experimentally verify the precision actually achievable in case of extremely irregular, small target volumes. For this purpose, a complete treatment procedure was performed using a standard head phantom complemented with a specially developed insert that simulates an L-shaped lesion. The spatial precision of the irradiation was recorded by means of high-resolution film dosimetry using GafChromic films. The analysis of the films showed for the film in the center plane an excellent conformity of the 75% isodose line used to circumscribe the lesion. A very good agreement between planning and measurement resulted also for isodose lines residing outside of the target volume.

Object: The purpose of the paper is to describe a workable three-dimensional dosimetry system for use in quality assurance programs of departments in which radiosurgery is performed., Methods: A system was developed on the basis of radiochromatic films. The experimental findings of the measured dose distributions for small complex-shaped targets, within a specially designed phantom, are described and compared with the same parameters calculated from the corresponding dose plan. The following parameters were determined for 83 patients with irregularly shaped targets who underwent gamma knife radiosurgery (GKS): target volume; dose-volume histograms of the target; 12-Gy, 15-Gy, and 18-Gy volumes; dose plan conformity; dose fall profiles in all dimensions to 50% of the prescription dose; and a quality factor (QF) to evaluate the adequacy of a GKS plan or treatment. The precise function and accuracy of the developed measuring device is shown and it demonstrated the expected steep dose falloff outside the irregularly shaped targets in all directions. The dose falloff was of the order of > 3 Gy/mm and the values of the QF were in the range between 0.5 and 0.9., Conclusions: A comparison with data from the literature shows that at least for small targets (< 2 cm3 and < 2.5 cm3) simulated within a head phantom, the dose gradient is significantly steeper in all directions than when using alternative treatment devices in radiosurgery and the overall QF is superior in most of the cases.

Twenty-one adult dry-bone sacral specimens were used to quantitatively determine the location of the sacral pedicle, foramina, and ala on the lateral radiographic view of the sacrum. The anterior and posterior sacral foramina from S1 to S3, the midlines of the anterior sacrum and cephalad border of the S1 vertebral body, and the lateral limit of the lateral sacral mass were outlined with wires. A lateral radiograph was taken, and measurements were made directly from the radiograph. The average sacral pedicle height for both male and female specimens was approximately 20 mm for S1, 12 mm for S2, and 7 mm for S3. The sacral foramina height averaged approximately 13 mm for S1 and S2, and 10 mm for S3. The average ala and S1 body-ala angles were 88 degrees and 35 degrees. The distance from the ala tip to the anterior aspect of the sacrum averaged 12 mm, and the average anterior height of the S1 vertebral body above the ala was 11 mm. These measurements, in conjunction with inlet and outlet radiographs, may aid in the recognition of the vital structures of the sacrum on the lateral radiographic view and enhance the safety of dorsal sacral screw placement.

Study Design: An evaluation of the vertebral artery groove of the atlas vertebra using dry bony vertebrae., Objectives: To measure the dimension of the vertebral artery groove of the atlas and to define its relation to the posterior midline., Summary of Background Data: Anatomic descriptions of the vertebral artery groove of the atlas exist, but very little quantitative data focused on this groove have been reported., Methods: Fifty dry atlas vertebrae were obtained for this study. Anatomic evaluation focused on the vertebral artery groove and its relation to the midline. A total of eight linear and two angular measurements were made bilaterally. The mean, range, and standard deviation were calculated for all of the specimens and for male and female specimens separately., Results: Differences in dimensions of male and female specimens were found to be statistically significant in one linear and two angular parameters. The average depths of the medial and lateral entrances, lengths of the axis, and thicknesses of the vertebral artery groove for male and female specimens were 9 mm, 6 mm, 14 mm, and 4 mm, respectively. The average angle of the vertebral artery groove axis for both genders was 64 degrees lateral to the sagittal plane. The distances from the midline to the medial-most edge of the vertebral artery groove on the inner and outer cortexes for male and female specimens averaged 10 mm, with a minimum of 8 mm, and 18 mm, with a minimum of 12 mm, respectively., Conclusions: The results of this study suggest that dissection on the posterior aspect of the posterior ring should remain within 12 mm lateral to the midline, and dissection on the superior aspect of the posterior ring should remain within 8 mm of the midline.

Eighteen adult paired atlas and axis specimens were used in conjunction with computer analysis to determine the average transverse canal area of the axis after different degrees of anterior translation and three types of rotation of the atlas. After each displacement, the remaining transverse canal area of the axis was calculated. The data showed that the mean transverse canal area of the axis was 351.5 +/- 8.8 mm2 for males and 276.9 +/- 8.6 mm2 for females, respectively. After a 3-, 4-, and 5-mm anterior translation of the atlas, the mean transverse canal area of the axis decreased to 300.4 +/- 5.1 mm2 (85.5%) for males and 238.0 +/- 2.1 mm2 (85.9%) for females, 283.9 +/- 5.9 mm2 (80.8%) for males and 228.5 +/- 3.1 mm2 (82.5%) for females, and 260.4 +/- 4.2 mm2 (74.1%) for males and 216.4 +/- 2.8 mm2 (78.2%) for females, respectively. After a 40 degree rotation, 40 degree rotation with 4-mm anterior translation, and 40 degree rotation with 8-mm anterior translation of the atlas, the mean transverse canal area of the axis for both sexes decreased approximately to 58%, 42%, and 23%, respectively. This study confirmed that the size of the transverse canal area of the axis was consistently correlated with the degrees of the anterior translation and rotation of the atlas.

Eighteen adult dry-bone spine specimens were used in conjunction with computer analysis to determine the average axial spinal canal area at the levels of C6, C7, and T1 after different degrees of anterior translation of the cephalad vertebra. Simulating a distractive flexion injury, the cephalad vertebra was anteriorly displaced on the caudal vertebra at 1-mm intervals. After each displacement, the remaining axial spinal canal area of the caudal vertebra was calculated. The results showed that the average axial spinal canal areas for both male and female specimens were approximately 222 mm2 for C6, 217 mm2 for C7, and 210 mm2 for T1, respectively. After a 6-mm anterior translation of the cephalad vertebra (assuming 50% of anterior translation of the vertebral body), the average axial spinal canal area of the caudal vertebra for both sexes significantly decreased to 59% at C6, 51% at C7, and 56% at T1, respectively. This study suggests that the size of the axial spinal canal directly depends on the degree of anterior vertebral translation.

Landau-Kleffner syndrome (LKS) is an acquired epileptic aphasia caused by a lesion in the speech centers of the cerebral cortex during a critical period of childhood development. Characteristics of LKS include language deterioration, seizure disorders, and severe electroencephalogram abnormalities. Multiple subpial transection (MST) is a surgical procedure that eliminates seizure activity in the cerebral cortex while preserving the child's normal cortical functions of speech, movement, primary sensation, and memory. This article presents a summary of clinical studies on LKS and discusses the diagnosis of LKS, traditional medical treatments, patient selection for MST procedures, and perioperative care of children undergoing MST procedures.

The role of the antiproteases alpha 1-proteinase inhibitor (alpha 1PI) and mucus proteinase inhibitor (MPI) in human lung emphysema was investigated by measuring their amount and functional activity against trypsin, leukocyte elastase, and pancreatic elastase in the bronchoalveolar lavage fluid (BALF). In addition, leukocyte elastase was quantified in the lavage samples by measuring the concentration of the elastase-alpha 1PI-complex. The study population consisted of 38 patients (5 nonsmokers, 8 former smokers, 25 smokers) with acquired emphysema (i.e., emphysema which is not caused by alpha 1PI deficiency), and 44 individuals (16 nonsmokers, 8 former smokers, 20 smokers) without emphysema. No differences were found between patients with and without emphysema in the activities of alpha 1PI and MPI, or in the concentration of alpha 1PI. The concentration of MPI was significantly higher in the BALF of patients with emphysema than in that of patients without emphysema (p = 0.025). A significantly higher concentration of elastase-alpha 1PI complex was found in patients with emphysema than in those without emphysema (p = 0.041). This finding could reflect the higher proteinase burden to which patients with emphysema are exposed. The increase of MPI in lavage fluid of patients with emphysema seems to be the result of increased production in emphysematous lungs. However, it remains unclear why patients develop emphysema while showing an increased content of MPI.

The clinical course and pulmonary function tests of individuals with severe Alpha-1-Antitrypsin (Alpha-1-AT) deficiency reveal a marked interindividual variability. 4 patients with PI type ZZ and 2 patients with PI type SZ had been identified by neonatal cholestasis. None had pulmonary symptoms at a mean age of 13 (range 9-16) years. Lung function tests disclosed signs of incipient pulmonary emphysema in one girl. Bronchial hyperreactivity had led to the diagnosis of Alpha-1 AT-deficiency (PI type ZZ) in another girl at the age of 7 years. The biochemical analysis of the serum of three children (two PI ZZ and one PI SZ) revealed additional protease inhibitors that may be effective as compensatory mechanisms. The lack of those protective factors as well as the presence of environmental hazards may contribute to the increased risk of emphysema in individual patients.

Smoking habits have no differentiating effect on the functional activity of protease inhibitor (alpha 1PI) in the serum and bronchoalveolar lavage fluid (BALF). In the BALF, the trypsin-inhibitory capacity TIC/alpha 1PI ratio is significantly greater in patients with emphysema than in non-emphysematous subjects. PIC/alpha 1PI ratios that are greater than 1 demonstrate the existence of additional antiproteases in the lower respiratory tract.

Both the clinical course of the homozygous alpha 1-PI deficiency and also the pulmonary function and measured clinical parameters in these children revealed very marked inter-individual fluctuations. In one child, the lung function revealed certain signs of incipient pulmonary emphysema. The biochemical parameters of two children revealed TIC/alpha 1-PI- and PEIC/alpha 1-PI ratios greater than 1. This indicates that, in addition to alpha 1-PI, further inhibitors may develop a compensatory effect.

Pulmonary emphysema is thought to be due to an elastase-antielastase imbalance which leads to the destruction of alveolar walls. It is generally agreed that cigarette smoking is the major cause of acquired emphysema although many smokers fail to develop overt disease. Cigarette smoke inactivates alpha 1-proteinase inhibitor (alpha 1PI) which is believed to be the major antielastase in the lower respiratory tract. There is, however, controversy regarding the activity of alpha 1PI in smokers compared with nonsmokers. We, therefore, investigated the trypsin inhibitory capacity (TIC), the pancreatic elastase inhibitory capacity (PEIC), and the amount of immunoreactive alpha 1PI in serum and bronchoalveolar lavage fluid (BALF) of 24 individuals (15 smokers, 5 former smokers, 4 non-smokers) with clinical signs of emphysema and 32 persons (15 smokers, 6 former smokers, 11 non-smokers) without emphysema. Pancreatic elastase is known to be inhibited only by non-oxidised alpha 1PI whereas trypsin is inhibited by both native and oxidised alpha 1PI. Serum values of TIC/alpha 1PI and PEIC/alpha 1PI did not differ between the groups of subjects with emphysema (TIC/alpha 1PI: 0.71 +/- 0.12; PEIC/alpha 1PI: 0.44 +/- 0.06) and without emphysema (TIC/alpha 1PI: 0.68 +/- 0.13; PEIC/alpha 1PI: 0.41 +/- 0.07). Both serum-inhibitory capacities were found to be smaller than unit (= 1) indicating inactivation of alpha 1PI. BALF values of TIC/alpha 1PI showed a wide variation. TIC/alpha 1PI was greater than unity in 84% of subjects with emphysema (2.06 +/- 1.28) compared to 61% without emphysema (1.14 +/- 1.07) providing evidence for the presence of additional inhibitor(s) in those lavage fluids.(ABSTRACT TRUNCATED AT 250 WORDS)

The plasma membranes of the glycogen-free and the glycogen-containing subline of Ehrlich-Lettrè ascites cells were purified and compared with respect to their enzyme activity, chemical, lipid and protein composition, and membrane fluidity. Both membrane fractions differed in a number of parameters which are discussed as differences in the expression of malignant transformation of the two sublines. 1. The 5'-nucleotidase activity was 3-5 times higher and the sialic acid content 3-times lower in the glycogen-containing than in the glycogen-free subline. 2. Differences were also observed with respect to the phospholipid composition, that is in the relative proportions of mainly phosphatidylcholine, -inositol and -serine. 3. The fatty acid spectrum of the two sublines differed in the C-18 series and in the percentage of polyunsaturated acids, which was about 6% lower in the glycogen-containing line. 4. Measurements of fluorescence polarization (P) using 1,6-diphenyl-1,3,5-hextriene as probe generally gave higher P values, indicating a decreased membrane fluidity for the plasma membranes of the glycogen-containing subline both below and above the transition temperature at 33 degrees C. 5. Polyacrylamide gel electrophoresis revealed different protein patterns mainly in the molecular weight range of around 90 000 and in the range between 31 000 and 14 000.