bluuebunny/crossref_metadata_2025 huggingface dataset:
Aerosol specification in single-column CAM5
Authors: Lebassi-Habtezion B. , Caldwell P.
Published: November 2014

Abstract. The ability to run a global climate model in single-column mode is very useful for testing model improvements because single-column models (SCMs) are inexpensive to run and easy to interpret. A major breakthrough in Version 5 of the Community Atmosphere Model (CAM5) is the inclusion of prognostic aerosol. Unfortunately, this improvement was not coordinated with the SCM version of CAM5 and as a result CAM5-SCM initializes aerosols to zero. In this study we explore the impact of running CAM5-SCM with aerosol initialized to zero (hereafter named Default) and test three potential fixes. The first fix is to use CAM5's prescribed aerosol capability, which specifies aerosols at monthly climatological values. The second method is to prescribe aerosols at observed values. The third approach is to fix droplet and ice crystal numbers at prescribed values. We test our fixes in four different cloud regimes to ensure representativeness: subtropical drizzling stratocumulus (based on the DYCOMS RF02 case study), mixed-phase Arctic stratocumulus (using the MPACE-B case study), tropical shallow convection (using the RICO case study), and summertime mid-latitude continental convection (using the ARM95 case study). Stratiform cloud cases (DYCOMS RF02 and MPACE-B) were found to have a strong dependence on aerosol concentration, while convective cases (RICO and ARM95) were relatively insensitive to aerosol specification. This is perhaps expected because convective schemes in CAM5 do not currently use aerosol information. Adequate liquid water content in the MPACE-B case was only maintained when ice crystal number concentration was specified because the Meyers et al. (1992) deposition/condensation ice nucleation scheme used by CAM5 greatly overpredicts ice nucleation rates, causing clouds to rapidly glaciate. Surprisingly, predicted droplet concentrations for the ARM95 region in both SCM and global runs were around 25 cm−3, which is much lower than observed. This finding suggests that CAM5 has problems capturing aerosol effects in this climate regime.
Historical impact of water infrastructure on water levels of the Mekong River and the Tonle Sap system
Authors: Cochrane T. A. , Arias M. E. , Piman T.
Published: November 2014

Abstract. The rapid rate of water infrastructure development in the Mekong Basin is a cause for concern due to its potential impact on fisheries and downstream natural ecosystems. In this paper, we analyze the historical water levels of the Mekong River and Tonle Sap system by comparing pre- and post-1991 daily observations from six stations along the Mekong mainstream from Chiang Saen (northern Thailand), to Stung Treng (Cambodia), and the Prek Kdam station on the Tonle Sap River. Observed alterations in water level patterns along the Mekong are linked to temporal and spatial trends in water infrastructure development from 1960 to 2010. We argue that variations in historical climatic factors are important, but they are not the main cause of observed changes in key hydrological indicators related to ecosystem productivity. Our analysis shows that the development of mainstream dams in the upper Mekong Basin in the post-1991 period may have resulted in a modest increase of 30-day minimum levels (+17%), but significant increases in fall rates (+42%) and the number of water level fluctuations (+75%) observed in Chiang Saen. This effect diminishes downstream until it becomes negligible at Mukdahan (northeast Thailand), which represents a drainage area of over 50% of the total Mekong Basin. Further downstream at Pakse (southern Laos), alterations to the number of fluctuations and rise rate became strongly significant after 1991. The observed alterations slowly decrease downstream, but modified rise rates, fall rates, and dry season water levels were still quantifiable and significant as far as Prek Kdam. This paper provides the first set of evidence of hydrological alterations in the Mekong beyond the Chinese dam cascade in the upper Mekong. Given the evident alterations at Pakse and downstream, post-1991 changes could also be directly attributed to water infrastructure development in the Chi and Mun basins of Thailand. A reduction of 23 and 11% in the water raising and falling rates respectively at Prek Kdam provides evidence of a diminished Tonle Sap flood pulse in the post-1991 period. Given the observed water level alterations from 1991 to 2010 as a result of water infrastructure development, we can extrapolate that future development in the mainstream and the key transboundary Srepok, Sesan, and Sekong sub-basins will have an even greater effect on the Tonle Sap flood regime, the lower Mekong floodplain, and the delta.
Understanding NMR relaxometry of partially water-saturated rocks
Authors: Mohnke O. , Nordlund C. , Jorand R. , Klitzsch N.
Published: November 2014

Abstract. Nuclear Magnetic Resonance (NMR) relaxometry measurements are commonly used to characterize the storage and transport properties of water-saturated rocks. These assessments are based on the proportionality of NMR signal amplitude and relaxation time to porosity (water content) and pore size, respectively. The relationship between pore size and NMR relaxation time depends on pore shape, which is usually assumed to be spherical or cylindrical. However, the NMR response at partial water saturation for natural sediments and rocks differs strongly from the response calculated for spherical or cylindrical pores, because these pore shapes cannot account for water menisci remaining in the corners of de-saturated angular pores. Therefore, we consider a bundle of pores with triangular cross-sections. We introduce analytical solutions of the NMR equations at partial saturation of these pores, which account for water menisci of de-saturated pores. After developing equations that describe the water distribution inside the pores, we calculate the NMR response at partial saturation for imbibition and drainage based on the deduced water distributions. For this pore model, NMR amplitude and NMR relaxation time at partial water saturation strongly depend on pore shape even so the NMR relaxation time at full saturation only depends on the surface to volume ratio of the pore. The pore-shape-dependence at partial saturation arises from the pore shape and capillary pressure dependent water distribution in pores with triangular cross-sections. Moreover, we show the qualitative agreement of the saturation dependent relaxation time distributions of our model with those observed for rocks and soils.
Periodic Glacial Lake Outburst Floods threatening the oldest Buddhist monastery in north-west Nepal
Authors: Kropáček J. , Neckel N. , Tyrna B. , Holzer N. , Hovden A. , Gourmelen N. , Schneider C. , Buchroithner M. , Hochschild V.
Published: November 2014

Abstract. Since 2004 Halji Village, home of the oldest Buddhist Monastery in north-west Nepal has suffered from recurrent Glacial Lake Outburst Floods (GLOFs). Studies of recent satellite images identified a supra-glacial lake, located at a distance of 6.5 km from the village, as a possible source of the flood. During a field survey in 2013, the finding was confirmed and several entrances to en-glacial conduits which are draining the lake were found. The topography of the lake basin was then mapped by combining Differential Global Positioning System (DGPS) measurements with a Structure From Motion (SFM) approach from terrestrial photographs. From this model the maximum filling capacity of the lake has been estimated as 1.06 × 106 m3 with a maximum discharge of 77.8 m3 s−1 calculated using an empirical relation. The flooded area in the valley has been estimated by employing a raster-based hydraulic model considering six scenarios of discharge volume and surface roughness. To understand the changes in glacier geometry in the last decade the thinning and retreat of Halji Glacier have been analysed by geodetic mass balance measurements and a time series of satellite images respectively. The GLOF occurrences have further been correlated with cumulative temperature and cumulative liquid precipitation calculated from the High Asia Reanalysis (HAR) dataset. Finally, effective mitigation measures and adaption strategies for Halji village have been discussed.
Regional Citrate Anticoagulation in Therapeutic Plasma Exchange with Fresh Frozen Plasma - a Modified Protocol
Authors: Betz Christoph , Buettner Stefan , Geiger Helmut , Jung Oliver
Published: November 2014

Purpose

In membrane-based therapeutic plasma exchange (TPE), regional citrate anticoagulation (RCA) is associated with difficulties because of citrate accumulation and consequent, potentially significant, metabolic complications, especially when using fresh frozen plasma (FFP) as replacement fluid. We modified the technical setup of a commercially available continuous veno-venous hemodi-alysis RCA module (multiFiltrate Ci-Ca®) to establish an RCA-protocol for TPE.

Methods

Description of the modified technical setup and retrospective analysis of the feasibility of the RCA-protocol for TPE in all patients treated between 2009 and 2010.

Results

411 consecutive TPE with RCA were performed in 42 patients, all using FFP as replacement fluid. Median procedure characteristics were: blood flow 160 ml/min, filtrate flow 36 ml/min, duration 93 min, processed total plasma volume 3600 mL. Trisodium citrate was infused at a rate of 0.43 mmol/min to achieve post-filter ionized calcium levels of ≤0.4 mmol/l. Calcium substitution rate was 0.19 mmol/min to maintain physiologic iCa levels. RCA was well tolerated with no significant differences in pH, iCa, bicarbonate or potassium after repeated sessions. Clotting events complicated 7.3% of the procedures. Adverse events occurred in 3.4% of TPE procedures; none was severe or fatal. No significant differences were observed comparing the rate of adverse events to those observed in TPE using standard anticoagulation at our center (4.8%).

Conclusions

We describe for the first time a modified protocol for RCA in TPE using an integrated citrate module. Based on our experience, this RCA protocol is a feasible alternative for anticoagulation in TPE with FFP, especially in patients with a high risk of bleeding.
Patient Clearance Time (tp) with Different Vascular access Types
Authors: Dounousi Evangelia C. , Balafa Olga C. , Gouva Chariklia D. , Karassavidou Despina P. , Mitsis Michail C. , Pappas Efthymios M. , Katopodis Konstantinos P.
Published: November 2014

Background/Aims

The dialysis delivered dose is limited by the rate at which urea can be transferred from the different body compartments. The time needed to clear the peripheral compartments of the body has been called the patient clearance time (tp). The aim of the study was to compare delivered dialysis dose using the tp index between patients dialyzed through a permanent central venous catheter (CVC) and patients with an arteriovenous fistula (AVF).

Methods

The study included 48 stable hemodialyzed patients. Patients were classified into two groups according to their vascular access type. The first group included 24 patients dialyzed through a permanent CVC and the second group consisted of 24 patients with a mature AVF. The following parameters were calculated twice for each patient: tp, Kt/V adjusted for the tp.

Results

tp was lower in the AVF dialysis modality than in CVC (26 ± 7 vs. 42 ± 14 min, p<0.001) while the (eqKt/V)tp was higher in AVF than in CVC dialysis (1.36 ± 0.11 vs. 1.19 ± 0.13, p<0.001).

Conclusions

The patient clearance time is lower in AVF than in CVC dialysis, and this is accompanied by a higher delivered dialysis dose.
Determination and Extension of the Limits to Static Cold Storage using Subnormothermic Machine Perfusion
Authors: Bruinsma Bote G. , Berendsen Tim A. , Izamis Maria-Louisa , Yarmush Martin L. , Uygun Korkut
Published: November 2014

Background/Aims

Static cold storage (SCS) of the liver for transplantation is limited by time. Continuation of metabolic activity leads to depletion of energy stores and loss of cellular function, which results in poor post-transplant function. Machine perfusion (MP) applied at the end of preservation may improve the viability of marginal liver grafts and provides information on the quality of the organ. We attempt to define the limits to SCS in terms of easily measurable perfusion parameters and investigate whether MP can improve liver viability.

Methods

Rat livers were cold-stored for 0, 24, 48, 72, and 120 h, after which they were treated with subnormothermic machine perfusion (SNMP). Livers cold-stored for 48 and 72 h were transplanted orthotopically with or without SNMP. During SNMP easily measurable parameters were monitored and adenosine triphosphate (ATP) content was measured following preservation and SNMP.

Results

ATP increased significantly during SNMP, but the recovered ATP content deteriorated with increased duration of SCS, with minimal improvement after 72 h of SCS. Vascular resistance during SNMP increased with extended preservation. After 48 h of SCS, orthotopic transplantation survival increased significantly from 50% to 100% with SNMP, but did not improve after 72 h.M

Conclusions

Vascular resistance and ATP recovery suggest a decrease in viability after 48 h of SCS. Survival data confirms the loss of post-transplant graft function and supports the use of ATP and vascular resistance as useful indicators. Further, we show that the recoverability of a liver using SNMP is limited to 48 h of SCS.
Improving RhoA-mediated Intestinal Epithelial Permeability by Continuous Blood Purification in Patients with Severe Acute Pancreatitis
Authors: Shen Qing , Gan Hua , Yang Mengxue , Huang Yang , Du Xiao-Gang , Chen Danyan , Zhang Han
Published: November 2014

Background

Early dysfunction of the intestinal mucosal barrier contributes to increasing intestinal permeability. It may play an important role in the pathophysiology of severe acute pancreatitis (SAP). A rising number of clinical data have showed that continuous blood purification (CBP) may improve the prognosis of SAP. However, the therapeutic effects of CBP on intestinal epithelial permeability have been rarely reported.

Methods

Intestinal epithelial monolayer (Caco-2) was incubated with serum samples collected at specific time points from SAP patients during CBP. Changes in intestinal epithelial monolayer permeability and configuration, and levels of cellular tight junction structural proteins including occludin and ZO-1, and RhoA mRNA expression level were recorded, respectively. In addition, serum tumor necrosis factor-alpha (TNF-α) levels at specific time points during CBP were determined.

Results

Before CBP initiation, intestinal epithelial permeability was increased and tight junction structural protein level was decreased and reorganized, but RhoA mRNA expression and serum TNF-α were increased. However, after CBP treatment, intestinal epithelial permeability was reduced and tight junction protein levels were increased, with reorganization attenuated. Meanwhile, RhoA mRNA expression and serum TNF-α level was decreased.

Conclusions

After CBP treatment, intestinal epithelial permeability was reduced by increasing oc-cludin and ZO-1 protein level and attenuating reorganization. This beneficial effect of CBP on intestinal epithelial permeability is associated with down-regulation of RhoA mRNA expression, and it may be related to the removal of TNF-α by CBP.
Microdialysis Monitoring of Glucose, Lactate, Glycerol, and Pyruvate in Patients with Diabetic Ketoacidosis
Authors: Ciechanowska Anna , Ladyzynski Piotr , Wojcicki Jan M. , Sabalinska Stanislawa , Krzymien Janusz , Pulawska Elzbieta , Karnafel Waldemar , Foltynski Piotr , Kawiak Jerzy
Published: November 2014

Purpose

The objective was to assess glucose, lactate, glycerol, and pyruvate concentrations in the interstitial fluid of the adipose tissue as well as the glucose relative recovery coefficient in reference to capillary blood (RC) during the first two days of the standard treatment of diabetic ketoacidosis (DKA) in patients with type 1 and type 2 diabetes.

Materials and Methods

The study group consisted of 19 patients (12 with type 1 diabetes and 7 with type 2 diabetes). The metabolic state of the patients was monitored using the microdialysis technique. The analysis of variance was used to investigate whether the type of diabetes and the duration of treatment influenced the assessed parameters.

Results

Concentrations of all the monitored components were stable after the initial 12 h of treatment. Glucose concentration was higher and concentrations of all the other components were lower (p<0.0001) in patients with type 1 diabetes than in patients with type 2 diabetes. Significantly higher RC was observed in patients with type 1 diabetes during the initial 12 h.

Conclusions

The results suggest that the standard treatment of DKA is effective in stabilizing a concentration of the studied metabolic components in the interstitial fluid in patients with type 1 and type 2 diabetes despite differences in the glucose concentration at the beginning of the treatment.
Mechanical Study of Polycaprolactone-hydroxyapatite Porous Scaffolds Created by Porogen-based Solid Freeform Fabrication Method
Authors: Lu Lin , Zhang Qingwei , Wootton David M. , Chiou Richard , Li Dichen , Lu Bingheng , Lelkes Peter I. , Zhou Jack
Published: November 2014

Materials and Methods

Polycaprolactone (PCL) and polycaprolactone-hydroxyapatite (PCL-HA) scaffolds with 600-μm pore size were fabricated by drop-on-demand printing (DDP) structured porogen method followed with injection molding. Specimens with special dimensions of 4.2×4.2×5.4 mm3 and 6.6×6.6×13.8 mm3 were designed and fabricated for compression and tensile tests, respectively. The mechanical study was performed on both solid and porous PCL and PCL-HA samples. The effect on mechanical properties of the HA content ratio in PCL-HA composites was investigated.

Results

Porous scaffold made of 80/20 PCL-HA composite had an ultimate compressive strength of 3.7±0.2 MPa and compression modulus of 61.4±3.4 MPa, which is in the range of reported trabecular bone's compressive strength. Increasing the concentration of HA in the composites raised compressive properties and stiffness significantly (P<0.05), which demonstrates that PCL-HA composites have the potential for application in bone regeneration. Tensile test of solid PCL and PCL-HA composites showed that the ultimate tensile strength and tensile modulus increased with increases of the concentration of HA in the composites. The tensile test was also conducted on PCL porous scaffold; the result indicated that the scaffold was slightly softer and weaker in tension compared with compression.

Conclusions

Combining compression and tensile test results, our study may guide the possible application of these biomaterials in bone tissue engineering and support further development of microstructure-based models of scaffold mechanical properties.
Structural Behavior of Human Lumbar Intervertebral Disc under Direct Shear
Authors: Schmidt Hendrik , Häußler Kim , Wilke Hans-Joachim , Wolfram Uwe
Published: November 2014

Purpose

The intervertebral disc (IVD) is a complex, flexible joint between adjacent vertebral bodies that provides load transmission while permitting movements of the spinal column. Finite element models can be used to help clarify why and how IVDs fail or degenerate. To do so, it is of importance to validate those models against controllable experiments. Due to missing experimental data, shear properties are not used thus far in validating finite element models. This study aimed to investigate the structural shear properties of human lumbar IVDs in posteroanterior (PA) and laterolateral (LL) loading directions.

Methods

Fourteen lumbar IVDs (median age: 49 years) underwent direct shear in PA and LL loading directions. A custom-build shear device was used in combination with a materials testing machine to load the specimens until failure. Shear stiffness, ultimate shear force and displacement, and work to failure were determined.

Results

Each specimen was tested until complete or partial disruption. Median stiffness in PA direction was 490 N/mm and in LL direction 568 N/mm. Median ultimate shear force in the PA direction was 2,877 N and in the LL direction 3,199 N. Work to failure was 12 Nm in the PA and 9 Nm in the LL direction.

Conclusions

This study was an experiment to subject IVDs to direct shear. The results could help us to understand the structure and function of IVDs with regard to mechanical spinal stability, and they can be used to validate finite element models of the IVD.
Enamel Structural Changes induced by Hydrochloric and Phosphoric Acid Treatment
Authors: Bertacci Angelica , Lucchese Alessandra , Taddei Paola , Gherlone Enrico F. , Chersoni Stefano
Published: November 2014

Purpose

The aim of this study was to evaluate enamel acid-induced structural changes after 2 different treatments, by means of Raman and infrared (IR) spectroscopy analyses, and to correlate these findings with permeability measured as fluid discharge from outer enamel.

Methods

Two different treatments were investigated: 10 enamel slices were etched with 15% hydrochloric acid (HCl) for 120 seconds and 10 slices with 37% phosphoric acid gel (H3PO4) for 30 seconds, rinsed for 30 seconds and then air-dried for 20 seconds. Powders of enamel treated as previously described were produced. Replicas of enamel subjected to the same treatments were obtained to evaluate the presence of fluid droplets on enamel surface.

Results and Conclusions

Raman and IR spectroscopy showed that the treatment with both hydrochloric and phosphoric acids induced a decrease in the carbonate content of the enamel apatite. At the same time, both acids induced the formation of HPO42- ions. After H3PO4 treatment, the bands due to the organic component of enamel decreased in intensity, while they increased after HCl treatment. Replicas of H3PO4 treated enamel showed a strongly reduced permeability. Replicas of HCl 15% treated samples showed a maintained permeability. A decrease of the enamel organic component, as resulted after H3PO4 treatment, involves a decrease in enamel permeability, while the increase of the organic matter (achieved by HCl treatment) still maintains enamel permeability. The results suggested a correlation between organic matter and enamel permeability. Permeability was affected by etching technique and could be involved in marginal seal, gap and discoloration at the enamel interface, still causes of restoration failure.
Issues in Nanocomposite Ceramic Engineering: Focus on Processing and Properties of Alumina-based Composites
Authors: Palmero Paola , Kern Frank , Sommer Frank , Lombardi Mariangela , Gadow Rainer , Montanaro Laura
Published: November 2014

Ceramic nanocomposites, containing at least one phase in the nanometric dimension, have received special interest in recent years. They have, in fact, demonstrated increased performance, reliability and lifetime with respect to monolithic ceramics. However, a successful approach to the production of tailored composite nanostructures requires the development of innovative concepts at each step of manufacturing, from the synthesis of composite nanopowders, to their processing and sintering. This review aims to deepen understanding of some of the critical issues associated with the manufacturing of nanocomposite ceramics, focusing on alumina-based composite systems. Two case studies are presented and briefly discussed. The former illustrates the benefits, in terms of sintered microstructure and related mechanical properties, resulting from the application of an engineering approach to a laboratory-scale protocol for the elaboration of nanocomposites in the system alumina-ZrO2-YAG (yttrium aluminium garnet). The latter illustrates the manufacturing of alumina-based composites for large-scale applications such as cutting tools, carried out by an injection molding process. The need for an engineering approach to be applied in all processing steps is demonstrated also in this second case study, where a tailored manufacturing process is required to obtain the desired results.
Nitric Oxide Release from Polydimethylsiloxane-based Polyurethanes
Authors: Nguyen Evelyne B. , Zilla Peter , Bezuidenhout Deon
Published: November 2014

Localized nitric oxide (NO) release from polymeric materials holds much promise for the prevention of coagulation often associated with implantable and extracorporeal blood-contacting devices. Films of polyurethane (PU) containing incorporated polyethyleneimine were thus exposed to NO gas to form diazeniumdiolates (NONOates) in situ. Donor incorporation and NO gas exposure did not affect the mechanical properties of the films. The NO release capacity increased with increasing polydimethylsiloxane (PDMS) content in the soft segment of the PU: total capacity could be more than doubled (P<0.05) from 0.093 ± 0.028 to 0.225 ± 0.004 mmol/g when the PDMS content was increased from 0 to 100%. Release kinetics were best approximated using a modified Korsemeyer-Peppas power law (R2=0.95-0.99). Despite the resultant rapid initial decrease in NO release rates, values above that observed for quiescent endothelial cells (0.83 pmol·cm−2·s−1) were maintained for extended periods of 5-10 days, while rates above that of a stimulated endothelium (2.7-6.8 pmol·cm−2·s−1) were achieved for the first 24 hours. This method of NONOate formation may be advantageous, as potential premature NO release by exposure of diazeniumdiolated donors during incorporation, processing and storage, can be avoided by in situ diazoniumdiolation closer to the time of implantation.
Mechanical Characterization of Human Gastrocolic Ligament until Failure
Authors: Chebil Omar , Arnoux Pierre-Jean , Behr Michel
Published: November 2014

Road accidents can lead to abdominal injuries ranging from severe to lethal, that include hemorrhage of organs and their attachment system. A good understanding and prediction of abdominal injuries therefore requires investigation of the mechanical properties of the attachment systems of abdominal organs. In particular, the gastrocolic ligament (GCL) is one major link between the stomach and the transverse colon. This study aims to investigate the mechanical properties of the GCL under very low and high strain rate uniaxial tensile tests until failure. Thirty-five GCL samples were dissected from 7 embalmed cadavers and tested at a rate of 1 mm/s and 1 m/s. Incidence of freezing was also evaluated. The mechanical response of GCL samples showed an approximately bilinear curve. Within the first linear region (less than 5% of ligament strain), the apparent elastic modulus was estimated at 247±144 kPa, while in the second region, it was estimated at 690±282 kPa. The average failure stress (σfail) and failure strain (∊fail) were 131.6±50 kPa and 29%±8%, respectively. High strain rate loading also showed high sensitivity to strain rate. The estimated GCL mechanical properties in this study can be implemented in finite element models of the abdomen to further investigate the mechanical contribution of the organ attachment system under traumatic loading conditions.
Thermal Isotherms in PMMA and Cell Necrosis during Total Hip Arthroplasty
Authors: Gundapaneni Dinesh , Goswami Tarun
Published: November 2014

Background

Polymethylmethacrylate (PMMA), also known as bone cement, is a commonly used adhesive material to fix implants in Total Hip Arthroplasty (THA). During implantation, bone cement undergoes a polymerization reaction which is an exothermic reaction and results in the release of heat to the surrounding bone tissue, which ultimately leads to thermal necrosis. Necrosis in the bony tissue results in early loosening of the implant, which causes pain and reduces the life of the implant.

Purpose

The main objective of the present study was to understand the thermal isotherms in PMMA and to determine the optimal cement mantle thickness to prevent cell necrosis during THA.

Methods

In this study, the environment in the bony tissue during implantation was simulated by constructing 3D solid models to observe the temperature distribution in the bony tissue at different cement mantle thicknesses (1 mm, 3 mm and 5 mm), by applying the temperature conditions that exist during the surgery. Stems made with Co-Cr-Mo, 316L stainless steel and Ti6Al4V were used, which acted as heat sinks, and a thermal damage equation was used to measure the bone damage. FEA was conducted based on temperature conditions and thermal isotherms at different cement mantle thicknesses were obtained.

Results

Thermal isotherms derived with respect to distance in the bony tissue from the center of the cement mantle, and cell necrosis was determined at different mantle thicknesses. Based on the deduced results, cement mantle thickness of 1-5 mm does not cause thermal damage in the bony tissue.

Conclusion

Considering the long term stability of the implant, cement mantle thickness range from 3 mm-5 mm was found to be optimal in THA to prevent cell necrosis.
Biomechanical Properties: Effects of Low-level Laser Therapy and Biosilicate® on Tibial Bone Defects in Osteopenic Rats
Authors: Fangel Renan , Bossini Paulo S. , Renno Ana Cláudia , Granito Renata N. , Wang Charles C. , Nonaka Keico O. , Driusso Patricia , Parizotto Nivaldo A. , Oishi Jorge
Published: November 2014

Purpose

The aim of this study was to investigate the effects of laser therapy and Biosilicate® on the biomechanical properties of bone callus in osteopenic rats.

Methods

Fifty female Wistar rats were equally divided into 5 groups (n=10/group): osteopenic rats with intact tibiae (SC); osteopenic rats with unfilled and untreated tibial bone defects (OC); osteopenic rats whose bone defects were treated with Biosilicate® (B); osteopenic rats whose bone defects were treated with 830-nm laser, at 120 J/cm2 (L120) and osteopenic rats whose bone defects were treated with Biosilicate® and 830-nm laser, at 120 J/cm2 (BL120). Ovariectomy (OVX) was used to induce osteopenia. A non-critical bone defect was created on the tibia of the osteopenic animals 8 weeks after OVX. In Biosilicate® groups, bone defects were completely filled with the biomaterial. For the laser therapy, an 830-nm laser, 120 J/cm2 was used. On day 14 postsurgery, rats were euthanized, and tibiae were removed for biomechanical analysis.

Results

Maximal load and energy absorption were higher in groups B and BL120, according to the indentation test. Animals submitted to low-level laser therapy (LLLT) did not show any significant biomechanical improvement, but the association between Biosilicate® and LLLT was shown to be efficient to enhance callus biomechanical properties. Conversely, no differences were found between study groups in the bending test.

Conclusions

Biosilicate® alone or in association with low level laser therapy improves biomechanical properties of tibial bone callus in osteopenic rats.
Activation of EGFR Signaling from Pilocytic Astrocytomas to Glioblastomas
Authors: Carvalho Priscila O. , Uno Miyuki , Oba-Shinjo Sueli M. , Rosemberg Sergio , Wakamatsu Alda , da Silva Clemar C. , Teixeira Manoel J. , Marie Suely K. N.
Published: November 2014

Introduction

EGFR analyses allow for better correlation between genotype and phenotype in astrocytomas and represent an attractive therapeutic target. Most studies emphasize analyses of EGFR in glioblastomas (GBMs) but do not analyze all grades of astrocytomas (from pilocytic to GBM). The purpose of our study was to evaluate the status of EGFR (expression, deletion, and amplification) and EGFR protein expression in all grades of astrocytomas.

Patients and Methods

We analyzed a total of 145 surgical tumor specimens that included: 22 pilocytic astrocytomas, 22 grade II astrocytomas, 17 grade III astrocytomas and 84 GBMs. The specimens were compared to 17 non-neoplastic brain tissues obtained from epilepsy surgery. EGFR expression, EGFR amplification and EGFRvIII analyses were performed by quantitative real-time PCR, and protein expression was evaluated by immunohistochemistry.

Results

EGFR relative overexpression and EGFR amplification were observed, respectively, in 50% and 20% of astrocytomas, while EGFRvIII was only found in GBMs (34.5%, p=0.005). Amongst EGFR-amplified GBM cases, 59% also presented EGFRvIII (p<0.001). Cytoplasmic accumulation of EGFR protein was detected in 75% of astrocytomas, and 21% of the astrocytomas showed nuclear localization (p=0.003).

Conclusions

EGFR alterations were found in all grades of astrocytomas, from pilocytic to GBMs, while EGFRvIII was exclusively found in GBMs. These findings provide important information on the mechanisms involved in the progression of astrocytomas for determining whether EGFR status can be used for effective and specific therapy.
Clinicopathological and Prognostic Value of S100A4 Expression in Gastric Cancer: A Meta-Analysis
Authors: Ling Zhian , Li Ruolin
Published: November 2014

Purposes

For several years S100A4 has been implicated in tumor progression and prognosis. However, the prognostic value of S100A4 overexpression in patients with gastric cancer remains unknown. Therefore, we performed a meta-analysis to assess the relationship between S100A4 overexpression and clinical outcome of gastric cancer.

Methods and Results

Candidate studies were searched from PubMed, Embase, Cochrane Library, and ISI Web of Science. We included studies that evaluated the prognostic value of S100A4 expression in gastric cancer patients with regard to survival and a series of clinicopathological parameters. The pooled hazard ratios (HR) and odds ratios (OR) with 95% confidence intervals (CI) were used to estimate the effects. Ten studies, all from Asia, were included in the meta-analysis. The pooled analysis showed that S100A4 overexpression was significantly associated with worse overall survival (OS) (HR=1.86, 95% CI: 1.45-2.38, p<0.00001) without heterogeneity in the data (I2=43.6%, p=0.131). Furthermore, our results showed that S100A4 overexpression was significantly correlated with some clinicopathological parameters such as tumor grade, stage, metastasis, invasion, and relapse.

Conclusions

The results of our meta-analysis indicate that S100A4 overexpression correlates with more adverse clinical features and a poor prognosis of gastric cancer patients in Asia, thus suggesting that S100A4 could be a useful marker to evaluate progression and prognosis of Asian gastric cancer patients. More studies from Western countries with a larger number of tumors and standardized methods are required before significant conclusions can be drawn.
A Standardized Staining Protocol for L1CAM on Formalin-Fixed, Paraffin-Embedded Tissues Using Automated Platforms
Authors: Fogel Mina , Harari Ayelet , Müller-Holzner Elisabeth , Zeimet Alain G. , Moldenhauer Gerhard , Altevogt Peter
Published: November 2014

The L1 cell adhesion molecule (L1CAM) is overexpressed in many human cancers and can serve as a biomarker for prognosis in most of these cancers (including type I endometrial carcinomas). Here we provide an optimized immunohistochemical staining procedure for a widely used automated platform (VENTANA™), which has recourse to commercially available primary antibody and detection reagents. In parallel, we optimized the staining on a semi-automated BioGenix (i6000) immunostainer. These protocols yield good stainings and should represent the basis for a reliable and standardized immunohistochemical detection of L1CAM in a variety of malignancies in different laboratories.
Prognostic Significance of microRNA-221/222 Expression in Cancers: Evidence from 1,204 Subjects
Authors: Wang Jin , Liu Sha , Sun Guo Ping , Wang Fang , Zou Yan Feng , Jiao Yang , Ning Jie , Xu Jing
Published: November 2014

Background

The prognostic significance of the expression of the miR-221/222 family in cancer remains controversial. We here performed a meta-analysis of published data investigating the effects of miR-221/222 expression on both overall survival (OS) and disease-free survival (DFS) among patients with cancer.

Methods

A systematic search of the PubMed, Embase, Cochrane, and CNKI databases was performed with the last search being updated on March 15, 2013. The hazard ratio (HR) and its 95% confidence interval (95% CI) were used to assess the strength of association.

Results

A total of 17 studies involving 1,204 subjects were included in this meta-analysis. When assessing the prognostic significance of miR-221 expression, the pooled HR was 1.91 (95% CI: 1.28-2.85, p=0.002) for OS and 1.36 (95% CI: 0.88-2.09, p=0.163) for DFS. When assessing the prognostic significance of miR-222 expression, the pooled HR was 2.15 (95% CI: 1.51-3.06, p<0.0001) for OS and 1.37 (95% CI: 0.45-4.13, p=0.581) for DFS. We also found that an elevated miR-221 expression was significantly associated with poor OS when stratifying by ethnicity, cancer type, statistical methodology, sample, and quality assessment. There was no evidence of publication bias.

Conclusion

The meta-analysis demonstrates that the elevated expression of miR-221 and miR-222 is associated with poor OS in patients with cancer. The miR-221/222 cluster might be used as a potential therapeutic strategy in clinical practice. More work is required to fully elucidate the role of the miR-221/222 family in human tumors.
Association between SNPs in P53 Binding Regions and Risk of Esophageal Squamous Cell Carcinoma
Authors: Wang Kai , Liu Botao , Li Juan , Xiong Gang , Guan Xingying , Yang Kang , Bai Yun
Published: November 2014

Background

The tumor protein 53 (TP53 or p53) plays an important role in tumor suppression by binding to the regulatory region of its target genes. Single nucleotide polymorphisms (SNP) located in the p53 binding regions are likely to affect the expression of p53 target genes and may contribute to susceptibility to common diseases. The role of the genetic variations in esophageal squamous cell carcinoma (ESCC) has been well explored. However, the role of p53 binding region variations in esophageal cancer is poorly understood.

Methods

We investigated the association of 6 p53 binding region polymorphisms with susceptibility of 400 ESCC cases and 400 cancer-free controls in a Southwest Chinese population using the SNapShot assay. Differences in frequencies of the SPNs genotypes between cases and controls were evaluated using the chi-square test.

Results

We found that the C allele of rs1009316 in Bax and rs762624 in CDKN1A can decrease the risk of ESCC. In the multiple genetic model, we found that the rs2395655 in CDKN1A is related with the risk of ESCC, and that the G allele increases the susceptibility to ESCC (OR: 1.364; 95% CI: 1.104-1.685). We carried out a stratification analysis between alleles and risk of ESCC according to clinical stage. There was no relationship between these SNPs and clinical stage.

Conclusion

SNPs in the p53 binding region may modulate the risk of ESCC in the Southwest Chinese population.
Rising CEA Levels in a Patient with Colon Carcinoma: Metachronous Medullary Thyroid Cancer
Authors: Göksu Sema Sezgin , Göksu Uğur A. , Gündüz Seyda , Coşkun Hasan S.
Published: November 2014

Introduction

Carcinoembryonic antigen (CEA) is a commonly used tumor marker, and its value in colon cancer is well established. However it is overexpressed in many different tumors. Here we report a case of colorectal cancer with high postoperative CEA levels that were associated with medullary thyroid carcinoma.

Case

A 60-year old man was operated for colon cancer. Postoperative CEA level was 107.6 ng/mL, while preoperative CEA level was unknown. For the detection of distant metastasis or local recurrence, we performed 18-flouro deoxyglycose (FDG) positron emission tomography (PET) and computed tomography (CT). We observed an increased FDG accumulation in the right lobe of the thyroid. The patient had cystic and non-metabolic lesions in the liver, and started a treatment with FOLFOX regimen. After 3 months of chemotherapy CEA was still as high as 146 ng/mL. There was no pathologic FDG uptake other than the thyroid nodule in PET-CT. Fine needle aspiration of the thyroid nodule revealed a follicular neoplasia. The patient underwent total thyroidectomy and histopathology revealed a medullary thyroid carcinoma. Postoperative CEA levels then lowered to normal ranges.

Conclusion

The case we here report was a stage III colorectal cancer with high CEA levels. Our focus on searching a residual/metastatic disease made us blind to other possible explanations; in fact, none of us noticed the thyroid nodule. This case reminds us not to forget that high CEA levels can be associated with conditions other than colon cancer, such as thyroid medullary carcinoma.
MTHFR/p53 Polymorphisms as Genetic Factors for Cervical Intraepithelial Neoplasia and Cervical Cancer in HPV-infected Mexican Women
Authors: González-Herrera Lizbeth , Rodríguez-Morales Patricia , del Refugio González-Losa María , Pérez-Mendoza Gerardo , Canul-Canché Jaqueline , Rosado-López Iván , de Cetina Thelma Canto
Published: November 2014

We performed a case-control association study to evaluate the association between common polymorphisms in MTHFR (C677T and A1298C) and the Arg72Pro polymorphism in the p53 gene and the risk for cervical intraepithelial neoplasia (CIN) or invasive cervical cancer (ICC) in Mexican HPV-infected women. We included 131 women with diagnosis of CIN grade I-II and 78 with CIN III or ICC; as controls we also included 274 women with normal Pap smear and negative HPV test. Genotyping for MTHFR and p53 polymorphisms was performed by PCR-RFPLs. HPV was tested by Hybrid Capture II. Odds ratios and 95% confidence intervals were estimated. Genotype frequencies for the 3 studied polymorphisms were distributed according to the Hardy-Weinberg equilibrium. The A1298C-MTHFR polymorphism showed significant differences for the heterozygous AC genotype and the C allele, whereas the AA genotype and A allele resulted to be genetic risk factors for CIN or ICC (p<0.03). The Arg72Pro-p53 polymorphism showed for the genotypes Arg/Pro and Pro/Pro, and for the Pro allele, a significant association only to the risk for CIN (p<0.03). The MTHFR/p53 interaction showed that the genotype combinations AA/ArgArg and AA/ArgPro were associated, respectively, to the risk of ICC and CIN (p<0.05). This study suggests that the A1298C-MTHFR polymorphism contributes to the genetic risk for both CIN and ICC, whereas the Arg72Pro-p53 polymorphism only contributes to the risk for CIN. The MTHFR/p53 genetic combinations AA/ArgArg and AA/ArgPro are associated genetic risk factors for ICC and CIN in Mexican HPV-infected women.
Resistin -420C>G Promoter Variant and Colorectal Cancer Risk
Authors: Mahmoudi Touraj , Karimi Khatoon , Arkani Maral , Farahani Hamid , Vahedi Mohsen , Dabiri Reza , Nobakht Hossein , Asadi Asadollah , Mirakhorli Mojgan , Arshi Benafsheh , Derakhshan Arash , Zali Mohammad Reza
Published: November 2014

Purposes

Obesity is associated with an increased risk of colorectal cancer (CRC), and ghrelin (GHRL) and resistin (RETN) are thought to be related to obesity. Our aim was to investigate whether GHRL and RETN gene variants are associated with CRC risk.

Materials and Methods

All 414 subjects, including 197 cases with CRC and 217 controls, were genotyped for the GHRL (rs26802) and RETN (rs1862513) or -420C>G gene variants using the PCR-RFLP method.

Results

Our findings indicated that the RETN -420C>G “CC” genotype, compared with the “GG” and “GC” genotypes, was a marker of decreased CRC susceptibility; the difference remained significant after adjustment for age, BMI, gender, smoking status, NSAID use, and family history of CRC (p=0.020; OR=0.52, 95% CI=0.30-0.90). Furthermore, after adjustment for confounding factors, the -420C>G “CC” genotype, compared with the “GG” genotype, was associated with a decreased risk for CRC (p=0.044; OR=0.53, 95% CI=0.29-0.98). In addition, no significant difference was observed for the GHRL (rs26802) gene variant.

Conclusions

To our knowledge, this is the first study suggesting that the RETN -420C>G “CC” genotype is a marker of decreased CRC susceptibility. This observation is relevant from a scientific perspective and deserves further investigations.
Prognostic Value of Microvessel Density in Hepatocellular Carcinoma Patients: A Meta-Analysis
Authors: Li Yanyan , Ma Xuelei , Zhang Jing , Liu Xiaoxiao , Liu Lei
Published: November 2014

Introduction

The identification of microvessel density (MVD) in patients suffering from different types of cancer has become a hot point as an emerging and promising biomarker. The aim of the present study is to clarify the prognostic relevance of MVD in hepatocellular carcinoma (HCC).

Methods

Relevant articles were screened in PubMed and EMBASE databases. Patients' clinical characteristics, overall survival (OS), disease/recurrence-free survival (DFS/RFS), and MVD levels were extracted for further analysis. The statistical analysis derived from the Kaplan—Meier survival curves was calculated indirectly with the methods developed by Parmar, Williamson, and Tierney. Multivariate Cox hazard regression analysis was used directly in Stata 11.0. The pooled hazard ratio (HR) and 95% confidence interval (CI) were calculated to evaluate the prognostic role of MVD in HCC.

Results

Our online literature search identified 12 articles including a total of 1,138 HCC patients. Meta-analysis of all the included studies considering survival outcomes showed a positive correlation between poor prognosis and higher-MVD levels. The pooled HRs (and 95% CIs) for OS and DFS/RFS were respectively 2.08 [1.77-2.45] and 2.64 [2.12-3.29]. Subgroup analyses considering tumor stage (I-II/III-IV), tumor size (<5 cm/≥5 cm), differentiation (well/poor), or cirrhosis status (≥20%/<20%) were also conducted, and all the above analyses supported the prognostic role of MVD in HCC.

Conclusion

Our meta-analysis showed that the available evidence supports the proposition that MVD has a good predictive role in HCC, especially when the patients have late stage, large size, or poorly differentiated tumors.
HER2 as a Predictive Factor for Successful Neoadjuvant Anthracycline Chemotherapy of Locally Advanced and Early Breast Cancer
Authors: Wang Jiayu , Xu Binghe , Yuan Peng , Li Qing , Zhang Pin , Cai Ruigang , Ma Fei , Fan Ying , Luo Yang
Published: November 2014

Objective

The aim of this study was to look for predictive and prognostic factors in anthracycline-based neoadjuvant chemotherapy.

Methods

Three hundred and nine patients with early-stage or locally advanced breast cancer were enrolled in this study and preoperatively treated with neoadjuvant chemotherapies in intense dose-dense (cyclophosphamide + epirubicin) or conventional (paclitaxel + epirubicin) regimens. Outcome parameters included overall objective response rate, as well as factors for determining pathological features influencing the efficacy of chemotherapy, such as estrogen receptor, progesterone receptor, and HER2 status, Eastern Cooperative Oncology Group (ECOG) score, tumor size, tumor inflammation, and lymph node metastasis.

Results

The overall pathological complete response (pCR) rate was 14.3%, and the main factor affecting the efficacy of chemotherapy was HER2 expression. The pCR rate was significantly higher for patients with HER2 overexpression, compared with patients with low HER2 expression (27.5% vs. 9.6%, p<0.001). The recurrence risk for patients with pCR decreased 1.12-fold compared with patients without pCR (5-year disease-free survival [DFS]: 81.8% vs. 65.7%, p=0.038). Patients in the HER2 overexpression subgroup benefited more from pCR than those in the HER2 low expression group (5-year DFS: 86.4% vs. 62.1%, p=0.049).

Conclusion

HER2 overexpression in primary tumors might be a predictive marker for good efficacy of anthracycline-based neoadjuvant chemotherapy. The pCR is a suitable prognostic factor, even for patients with HER2 overexpression.