Periacinar Retraction Clefting in Nonneoplastic and Neoplastic Prostatic Glands: Artifact or Molecular Involvement

A space between neoplastic acini and prostatic stroma is not rare and studies have interpreted this as an artifact, considering the absence of endothelial cells indicating vascular invasion. Thus, the aims of this work were to characterize and correlate the occurrence and extent of retraction clefting with the reactivities of alpha and beta dystroglycan (alpha DG, beta DG), laminin, matrix metalloproteinase 2 (MMP-2), p63, insulin-like growth factor 1(IGF-1), vimentin, and fibroblast growth factor 2 (FGF-2). The study was based on nonneoplastic and neoplastic prostatic tissues obtained from necropsies and retropubic radical prostatectomies. The results showed that periacinar retraction clefting was significantly more frequent in prostatic carcinoma samples than in normal prostatic acini. Most of the neoplastic acini (72.0%) showed retraction clefting of more than 50% of circumference, which were significantly more frequent in Gleason score 7 and 6. Decreased collagen and reticular and elastic fibers were verified in the stroma around neoplastic acini. Weak and discontinuous alpha DG, beta DG, and laminin immunoreactivities and intensified MMP-2, vimentin, IGF-1 and FGF-2 immunoreactivities were verified in the neoplastic acini; p63 immunoreactivity was negative in all carcinomas. Thus, these findings showed that the lack of epithelial basal cells, DGs, and laminin and increased MMP-2, IGF-1, and FGF-7 could be considered important pathways in periacinar retraction occurrence. This study demonstrated the origin of and the biological mechanisms responsible for periacinar retraction clefting in prostatic carcinoma.

Influence of Osteopenia in Autogenous Bone Graft Healing With or Without Expanded Polytetrafluoroethylene Membranes: Histologic and Histomorphometric Study in Rats

Purpose: The aim of this study was to quantitatively evaluate and qualitatively describe autogenous bone graft healing with or without an expanded polytetrafluoroethylene (e-PTFE) membrane in ovariectornized rats. Materials and Methods: Eighty Wistar rats, weighing approximately 300 g each, were used. A graft was obtained from the parietal bone and fixed to the sidewall of each animal's left mandibular ramus. The animals were randomly divided into four experimental groups (n = 20 in each group): group 1, sham operated and autogenous bone graft only- group 2, sham operated and autogenous bone graft covered by e-PTFE membrane; group 3, ovariectornized (OVX) and autogenous bone graft only- group 4, OVX and autogenous bone graft covered by e-PTFE membrane. The animals were sacrificed at five different time points: immediately after grafting or at 7, 21, 45, or 60 days after grafting. Histologic examination and morphometric measurement of the sections were performed, and values were submitted to statistical analyses. Results: Both groups (sham and OVX) experienced loss of the original graft volume when it was not covered by the membrane, whereas use of the membrane resulted in additional bone formation beyond the edges of the graft and under the membrane. Histologic analysis showed integration of the grafts in all animals, although a larger number of marrow spaces was found in OVX groups. Conclusions: Association of bone graft with an e-PTFE membrane resulted in maintenance of its original volume as well as formation of new bone that filled the space under the membrane. Osteopenia did not influence bone graft repair, regardless of whether or not it was associated with e-PTFE membrane, but descriptive histologic analysis showed larger numbers of marrow spaces in the bone graft and receptor bed and formation of new bone in the OVX animals. INT J ORAL MAXILLOFAC IMPLANTS 2009;24:1074-1082

Evaluation and Application of TS-FF-AAS System Using Ceramic Tube as Atomization Cell for Tin Determination in Canned Foods

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effects of the postannealing atmosphere on the dielectric properties of (Ba, Sr)TiO3 capacitors: Evidence of an interfacial space charge layer

The dielectric properties of (Ba, Sr)TiO3 films were found to be remarkably sensitive to the postannealing treatment atmosphere. This study demonstrates that postannealing in an oxygen atmosphere increases the dielectric relaxation phenomenon and that postannealing in a nitrogen atmosphere produces a slight dielectric relaxation. Such dependence of the dielectric relaxation was related both to oxygen vacancies and to the presence of negatively charged oxygen, trapped at the grain boundary and/or at the electrode/dielectric film interface. (C) 2000 American Institute of Physics. [S0003-6951(00)00817-2].

Tibial segmental bone defect treated with bone plate and cage filled with either xenogeneic composite or autologous cortical bone graft

Tibia segmental defect healing in sheep were clinically, radiographically and histologically evaluated. Twelve young sheep aged four to five months were divided into two groups, G1 and G2. A 3.5 cm long segmental defect was created in the right tibial diaphysis with maintenance of the periosteum. The bone defects in both groups were stabilized with a bone plate combined with a titanium cage. In G1 the cage was filled with pieces of autologous cortical bone graft. In G2 it was filled with a composite biomaterial which consisted of inorganic bovine bone, demineralized bovine bone, a pool of bovine bone morphogenetic proteins bound to absorbable ultra-thin powdered hydroxyapatiteand bone-derived denaturized collagen. Except for one G1 animal, all of them showed normal limb function 60 days after surgery. Radiographic examination showed initial formation of periosteal callus in both groups at osteo-tomy sites, over the plate or cage 15 days postoperatively. At 60 and 90 days callus remodeling occurred. Histological and morphometric analysis at 90 days after surgery showed that the quantity of implanted materials in G1 and G2 were similar, and the quantity of new bone formation was less (p = 0.0048) and more immature in G1 than G2, occupying 51 +/- 3.46% and 62 +/- 6.26% of the cage space, respectively. These results suggest that the composite biomaterial tested was a good alternative to autologous cartical bone graft in this experimental ovine tibial defect. However, additional evaluation is warranted prior to its clinical usage.

Effect of denture fabrication and wear on closest speaking space and interocclusal distance during deglutition

Statement of problem. The accuracy of assessing maxillomandibular relationships for trial bases and dentures using phonetic and swallowing methods has not been compared to that observed with definitive prostheses. Thus, there is no evidence to prove whether measurements obtained through such methods remain the same after adaptation to dentures.Purpose. This study investigated changes in the closest speaking space, interocclusal rest space, and interocclusal distance during deglutition in edentulous patients during and after complete denture treatment.Material and methods. Eighteen edentulous subjects participated in this study and measurements were performed after 7 Intervals of time: (1) with occlusion rims and record bases following creation of the maxillomandibular relationship record, (2) with trial dentures, (3) at Insertion of definitive complete dentures, (4) 1 week, (5) 2 weeks, (6) 1 month, and (7) 3 months after insertion. Recordings of interocclusal distances were made with a mandibular kinesiograph. Closest speaking space was measured during the pronunciation of the word 'seis'. The distance between postural rest position and centric occlusion, or interocclusal rest space, was measured using a kinesiograph. Interocclusal distance during deglutition was tested by recording the closest mandibular position recorded during swallowing of 20 mL of water. Data were analyzed using repeated-measure ANOVA, followed by the Student-Newman-Keuls test (alpha=.05).Results. A significant (P <.01)reduction in the mean closest speaking space was found when it was evaluated using occlusion rims and record bases (4.6 mm) compared with other stages (3.0 to 3.4 mm). No significant differences were found in mean interocclusal rest space and interocclusal distance during deglutition among the time periods evaluated.Conclusions. The presence of occlusion rims can influence mandibular position during pronunciation of the /s/ sound. The arrangement of artificial teeth changes the closest speaking space. However, rest position and deglutition were not affected, either during denture fabrication or short-term use.

Quantitative estimates of time-averaging in terebratulid brachiopod shell accumulations from a modern tropical shelf

Quantitative estimates of time-averaging in marine shell accumulations available to date are limited primarily to aragonitic mollusk shells. We assessed time-averaging in Holocene assemblages of calcitic brachiopod shells by direct dating of individual specimens of the terebratulid brachiopod Bouchardia rosea. The data were collected from exceptional (brachiopod-rich) shell assemblages, occurring surficially on a tropical mixed carbonate-siliciclastic shelf (the Southeast Brazilian Bight, SW Atlantic), a setting that provides a good climatic and environmental analog for many Paleozoic brachiopod shell beds of North America and Europe. A total of 82 individual brachiopod shells, collected from four shallow (5-25 m) nearshore (<2.5 km from the shore) localities, were dated by using amino acid racemization (D-alloisoleucine/L-isoleucine value) calibrated with five AMS-radiocarbon dates (r(2) = 0.933). This is the first study to demonstrate that amino acid racemization methods can provide accurate and precise ages for individual shells of calcitic brachiopods.The dated shells vary in age from modern to 3000 years, with a standard deviation of 690 years. The age distribution is strongly right-skewed: the young shells dominate the dated specimens and older shells are increasingly less common. However, the four localities display significant differences in the range of time-averaging and the form of the age distribution. The dated shells vary notably in the quality of preservation, but there is no significant correlation between taphonomic condition and age, either for individual shells or at assemblage level.These results demonstrate that fossil brachiopods may show considerable time-averaging, but the scale and nature of that mixing may vary greatly among sites. Moreover, taphonomic condition is not a reliable indicator of pre-burial history of individual brachiopod shells or the scale of temporal mixing within the entire assemblage. The results obtained for brachiopods are strikingly similar to results previously documented for mollusks and suggest that differences in mineralogy and shell microstructure are unlikely to be the primary factors controlling the nature and scale of time-averaging. Environmental factors and local fluctuations in populations of shell-producing organisms are more likely to be the principal determinants of time-averaging in marine benthic shelly assemblages. The long-term survival of brachiopod shells is incongruent with the rapid shell destruction observed in taphonomic experiments. The results support the taphonomic model that shells remain protected below (but perhaps near) the surface through their early taphonomic history. They may be brought back up to the surface intermittently by bioturbation and physical reworking, but only for short periods of time. This model explains the striking similarities in time-averaging among different types of organisms and the lack of correlation between time-since-death and shell taphonomy.

Comparative analysis of drilling frequencies in recent brachiopod-mollusk associations from the Southern Brazilian Shelf

Over 14,000 specimens-5,204 brachiopods, 9,137 bivalves, and 178 gastropods-acquired from 30 collecting stations (0 to 45 m depth) in the Ubatuba and Picinguaba bays, southern Brazil, were compared for drilling frequencies. Beveled (countersunk) circular-to-subcircular borings (Oichnus-like drill holes) were found in diverse bivalves but also in the rhynchonelliform brachiopod Bouchardia rosea-a small, semi-infaunal to epifaunal, free-lying species that dominates the brachiopod fauna of the southern Brazilian shelf. Drill holes in bivalve mollusks and brachiopods are comparable in their morphology, average diameter, and diameter range, indicating attacks by a single type of drilling organism. Drill holes in brachiopods were rare (0.4%) and found only at five sampling sites. Drillings in bivalves were over 10 times as frequent as in brachiopods, but the average drilling frequency was still low (5.6%) compared to typical boring frequencies of Cenozoic mollusks. Some common bivalve species, however, were drilled at frequencies up to 50 times higher than those observed for shells of B. rosea from the same samples. Due to scarcity of drilled brachiopods, it is not possible to evaluate if the driller displayed a nonrandom (stereotyped) site, size, or valve preference. Drilled brachiopods may record (1) naticid or muricid predation, (2) predation by other drillers, (3) parasitic drillings, and (4) mistaken or opportunistic attacks. Low drilling frequency in brachiopods is consistent with recent reports on ancient and modern examples. The scarcity of drilling in brachiopods, coupled with much higher drilling frequencies observed in sympatric bivalves, suggests that drilling in brachiopods may have been due to facultative or erroneous attacks. The drilling frequencies observed here for the brachiopod-bivalve assemblages are remarkably similar to those reported for Permian brachiopod-bivalves associations. This report adds to the growing evidence for an intriguing macroecological stasis: multiple meta-analytical surveys of present-day and fossil rhynchonelliform brachiopods conducted in recent years also point to persistent scarcity and low intensity of biotic interactions between brachiopods and drilling organisms throughout their evolutionary history.

A new Pennsylvanian Oriocrassatellinae from Brazil and the distribution of the genus Oriocrassatella in space and time

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

The dimension of the pore space in sponges

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Connection space approach to ambiguities of gauge theories

Two distinct gauge potentials can have the same field strength, in which case they are said to be copies of each other. The consequences of this ambiguity for the general affine space A of gauge potentials are examined. Any two potentials are connected by a straight line in A, but a straight line going through two copies either contains no other copy or is entirely formed by copies. Copyright © 2005 Hindawi Publishing Corporation.

Shelf-life of tail meat of the giant river prawn, Macrobrachium rosenbergii, stored on ice

The objective of this study was to evaluate the shelf-life of peeled giant river prawn Macrobrachium rosenbergii stored directly in contact with ice (DCI), and without direct contact with ice (WCI). The prawns from DCI treatment showed an intense leaching of non-protein nitrogen (NPN) and total volatile bases nitrogen (TVB-N), thus suggesting that NPN or TVB-N should not be used as freshness indicators of peeled tails stored directly in contact with ice. Loss of flavor and a quick texture tactile decrease with time occurred in both treatments. The shelf-life of peeled tails prepared from M. rosenbergii was 7 days for DCI and 10 days WCI. © 2006 by The Haworth Press, Inc. All rights reserved.

The temporal resolution of epibiont assemblages: Are they ecological snapshots or overexposures?

The effects of time averaging on the fossil record of soft-substrate marine faunas have been investigated in great detail, but the temporal resolution of epibiont assemblages has been inferred only from limited-duration deployment experiments. Individually dated shells provide insight into the temporal resolution of epibiont assemblages and the taphonomic history of their hosts over decades to centuries. Epibiont abundance and richness were evaluated for 86 dated valves of the rhynchonelliform brachiopod Bouchardia rosea collected from the inner shelf. Maximum abundance occurred on shells less than 400 yr old, and maximum diversity was attained within a century. Taphonomic evidence does not support models of live-host colonization, net accumulation, or erasure of epibionts over time. Encrustation appears to have occurred during a brief interval between host death and burial, with no evidence of significant recolonization of exhumed shells. Epibiont assemblages of individually dated shells preserve ecological snapshots, despite host-shell time averaging, and may record long-term ecological changes or anthropogenic environmental changes. Unless the ages of individual shells are directly estimated, however, pooling shells of different ages artificially reduces the temporal resolution of their encrusting assemblages to that of their hosts, an artifact of analytical time averaging. © 2006 by The University of Chicago. All rights reserved.

Histological findings following the use of a space-making device for bone reformation and implant integration in the maxillary sinus of primates

Background: Previous studies have shown that membrane elevation results in predictable bone formation in the maxillary sinus provided that implants can be placed as tent poles. In situations with an extremely thin residual crest which impairs implant placement, it is possible that a space-making device can be used under the sinus membrane to promote bone formation prior to placement of implants. Purpose: The present study was conducted to test the hypothesis that the use of a space-making device for elevation of the sinus membrane will result in predictable bone formation at the maxillary sinus floor to allow placement of dental implants. Materials and Methods: Eight tufted capuchin primates underwent bilateral sinus membrane elevation surgery, and a bioresorbable space-making device, about 6 mm wide and 6 mm in height, was placed below the elevated membrane on the sinus floor. An oxidized implant (Nobel Biocare AB, Gothenburg, Sweden) was installed in the residual bone protruding into the created space at one side while the other side was left without an implant. Four animals were sacrificed after 6 months of healing. The remaining four animals received a second implant in the side with a space-making device only and followed for another 3 months before sacrifice. Implant stability was assessed through resonance frequency analysis (RFA) using the Osstell™ (Osstell AB, Gothenburg, Sweden) at installation, 6 months and 9 months after the first surgery. The bone-implant contact (BIC) and bone area inside the threads (BA) were histometrically evaluated in ground sections. Results: Histologically there were only minor or no signs of bone formation in the sites with a space-making device only. Sites with simultaneous implant placement showed bone formation along the implant surface. Sites with delayed implant placement showed minor or no bone formation and/or formation of a dense fibrous tissue along the apical part of the implant surface. In the latter group the apical part of the implant was not covered with the membrane but protruded into the sinus cavity. Conclusions: The use of a space-making device, with the design used in the present study, does not result in bone formation at the sinus floor. However, membrane elevation and simultaneous placement of the device and an implant does result in bone formation at the implant surface while sites with implants placed 6 months after membrane elevation show only small amounts of bone formation. It is suggested that lack of stabilization of the device and/or a too extensive elevation of the membrane may explain the results. © 2009, Wiley Periodicals, Inc.

Search for supersymmetry in final states with missing transverse energy and 0, 1, 2, or ≥3 b-quark jets in 7 TeV pp collisions using the variable α T

A search for supersymmetry in final states with jets and missing transverse energy is performed in pp collisions at a centre-of-mass energy of s=7 TeV. The data sample corresponds to an integrated luminosity of 4.98 fb-1 collected by the CMS experiment at the LHC. In this search, a dimensionless kinematic variable, α T, is used as the main discriminator between events with genuine and misreconstructed missing transverse energy. The search is performed in a signal region that is binned in the scalar sum of the transverse energy of jets and the number of jets identified as originating from a bottom quark. No excess of events over the standard model expectation is found. Exclusion limits are set in the parameter space of the constrained minimal supersymmetric extension of the standard model, and also in simplified models, with a special emphasis on compressed spectra and third-generation scenarios.[Figure not available: see fulltext.] © 2013 CERN for the benefit of the CMS Collaboration.