bluuebunny/crossref_metadata_2025 huggingface dataset:
Co-occurrence of 1,4-dioxane with trichloroethylene in chlorinated solvent groundwater plumes at US Air Force installations: Fact or fiction
Authors: Anderson Richard H , Anderson Janet K , Bower Paul A
Published: April 2012

Increasing regulatory attention to 1,4-dioxane has prompted the United States Air Force (USAF) to evaluate potential environmental liabilities, primarily associated with legacy contamination, at an enterprise scale. Although accurately quantifying environmental liability is operationally difficult given limited historic environmental monitoring data, 1,4-dioxane is a known constituent (i.e., stabilizer) of chlorinated solvents, in particular 1,1,1-trichloroethane (TCA). Evidence regarding the co-occurrence of 1,4-dioxane and trichloroethylene (TCE), however, has been heavily debated. In fact, the prevailing opinion is that 1,4-dioxane was not a constituent of past TCE formulations and, therefore, these 2 contaminants would not likely co-occur in the same groundwater plume. Because historic handling, storage, and disposal practices of chlorinated solvents have resulted in widespread groundwater contamination at USAF installations, significant potential exists for unidentified 1,4-dioxane contamination. Therefore, the objective of this investigation is to determine the extent to which 1,4-dioxane co-occurs with TCE compared to TCA, and if these chemicals are co-contaminants, whether or not there is significant correlation using available monitoring data. To accomplish these objectives, the USAF Environmental Restoration Program Information Management System (ERPIMS) was queried for all relevant records for groundwater monitoring wells (GMWs) with 1,4-dioxane, TCA, and TCE, on which both categorical and quantitative analyses were carried out. Overall, ERPIMS contained 5788 GMWs from 49 installations with records for 1,4-dioxane, TCE, and TCA analytes. 1,4-Dioxane was observed in 17.4% of the GMWs with detections for TCE and/or TCA, which accounted for 93.7% of all 1,4-dioxane detections, verifying that 1,4-dioxane is seldom found independent of chlorinated solvent contamination. Surprisingly, 64.4% of all 1,4-dioxane detections were associated with TCE independently. Given the extensive data set, these results conclusively demonstrate for the first time that 1,4-dioxane is a relatively common groundwater co-contaminant with TCE. Trend analysis demonstrated a positive log-linear relationship where median 1,4-dioxane levels increased between approximately 6% and approximately 20% of the increase in TCE levels. In conclusion, this data mining exercise suggests that 1,4-dioxane has a probability of co-occurrence of approximately 17% with either TCE and/or TCA. Given the challenges imposed by remediation of 1,4-dioxane and the pending promulgation of a federal regulatory standard, environmental project managers should use the information presented in this article for prioritization of future characterization efforts to respond to the emerging issue. Importantly, site investigations should consider 1,4-dioxane a potential co-contaminant of TCE in groundwater plumes. Integr Environ Assess Manag 2012; 8: 731–737. © 2012 SETAC
The Danish case‐control study of cutaneous malignant melanoma. III. Hormonal and reproductive factors in women
Authors: Østerlind A. , Tucker M.A. , Stone B.J. , Jensen O.M.
Published: April 2012

The relationship between cutaneous malignant melanoma in women and reproductive and hormonal factors was investigated in a population‐based case‐control study including a total of 280 cases and 536 controls from East Denmark. Patients with lentigo maligna melanoma were not included. No association was found between risk of melanoma and age at menarche, duration of menstrual life, age at natural menopause, age at first pregnancy, or number of pregnancies, live births or miscarriages. There was no evidence of an association between melanoma and use, duration of use or type of oral contraceptives. The use of menopausal replacement therapy was not a risk factor for melanoma. There was no difference in risk associated with hormonal factors between superficial spreading melanoma and nodular melanoma. Our findings suggest that neither reproductive nor hormonal factors increase the risk of melanoma in women in Denmark.
Suppression of tuberculin skin reaction in healthy HTLV‐I carriers from Japan
Authors: Tachibana Nobuyoshi , Okayama Akihiko , Ishizaki Junzo , Yokota Tsutomu , Shishime Eiichi , Murai Koichi , Shioiri Shigemasa , Tsuda Kazunori , Essex Myron , Mueller Nancy
Published: April 2012

Although it is thought that infection with human T‐lymphotropic virus type I (HTLV‐I) is immunosuppressive, this has not been clearly demonstrated among healthy carriers, and there are no data concerning delayed‐type hypersensitivity (DTH). To evaluate this hypothesis, DTH to purified protein derivative (PPD) of tuberculin was measured in 126 healthy adults from an endemic area for HTLV‐I infection in southern Japan. Among the 39 HTLV‐I carriers, only 15% had detectable induration following PPD exposure, compared to 46% of the 87 non‐carriers. In addition, the size of erythema among those carriers with a positive reaction was about 70% of that among non‐carriers. Overall, there was a significantly inverse association between the degree of DTH response and prevalence of antibody. In relation to subjects with strong to moderate reaction, those with negative or indefinite reaction were 6 times more likely to be a carrier. This association was much stronger among subjects aged 60 years or older than among younger persons. These findings indicate that there is subclinical immunosuppression among HTLV‐I carriers, which increases with age.
Periampullary, colorectal and gastric cancer in two siblings
Authors: Schlossberg Daniel , Weber Walter , Stoffel Urs , Henggeler Karl , Stocker Hans , Foeppl Mario , Akovbiantz Arik
Published: April 2012

We describe a sibship affected by subsequent periampullary, colorectal and gastric carcinoma. Three of 4 siblings (2 males, 1 female) developed a periampullary carcinoma at the age of 20, and the 2 brothers subsequently had colorectal and gastric carcinoma. One of them also had familial adenomatous polyposis. There is suggestive evidence of vertical transmission of a gene predisposing to a hereditary colorectal carcinoma syndrome.
HTLV‐1 in Switzerland: Low prevalence of specific antibodies in HIV risk groups, high prevalence of cross‐reactive antibodies in normal blood donors
Authors: Schüpbach Jörg , Baumgartner Antonietta , Tomasik Zuzana
Published: April 2012

Sera from various Swiss population groups were tested for antibodies against the human T‐cell leukemia virus type 1 (HTLV‐1). Particle agglutination and ELISA were performed for screening; Western blot was done for confirmation. True‐positive sera were found at a prevalence of 0.12% in a cohort of 846 individuals at risk for AIDS tested in 1984–1985. Prevalences of 0.35% were found among 575 HIV‐1 positives tested in 1987, and of 1.3% among 292 HIV‐1 positives of a different group tested in 1988. The 6 positives found in our study represent the first cases of HTLV‐1 infection, or HIV‐1/HTLV‐1 double infection, diagnosed in Switzerland. In addition, high proportions of sera, regardless of whether they were from normal blood donors, HIV‐positives, or individuals at risk for AIDS, had antibodies that reacted weakly with one or several proteins of the size of viral gag proteins. The prevalence of such antibodies in normal donors was in the range of 10 to 40%, depending on the strictness of interpretation. Competition Western blots performed with some of these sera showed that these antibodies reacted with HTLV‐1, but not with HIV‐1 or cellular antigens, and had a lower affinity to HTLV‐1 proteins than the antibodies of human or goat antisera. The results indicate that these antibodies may be induced by agents immunologically related to, but different from, HTLV‐1, which are highly prevalent in the Swiss population. Oligopeptide stretches with sequence homology to HTLV‐1 are known to exist in various normal body proteins, several infectious agents including common viruses and protozoa, but the results might also indicate the existence of additional human retroviruses. Screening of blood donors with sensitive tests for antibodies to HTLV‐1 might produce an unacceptably high rate of false‐positive results, if stringent rules of interpretation analogous to those common in HIV screening are not used.
Mouse monoclonal antibodies for experimental immunotherapy promotes killing of tumor cells
Authors: Larson L.N. , Johansson C. , Lindholm L. , Holmgren J.
Published: April 2012

Monoclonal antibodies (MAbs) produced against a human colon adenocarcinoma cell line, Colo‐205, were tested in antibody‐dependent macrophage‐mediated cytotoxicity (ADMMC) assays. The antibodies C163, C215, C245 (IgG2a isotype); C1S1, C239, C241, C242 (IgG1); C152 (IgG2b); and C50 (IgM) were evaluated for their ability to promote killing of Colo‐205 cells by thioglycollate‐elicited peritoneal mouse macrophages. The concentrations of antibodies tested in ADMMC assays ranged from 1.0 ng/ml to 100 μg/ml, and the concentration at which 50% of tumor cells were lysed was used to characterize each antibody. Antibodies of the IgG2a isotype promoted the strongest macrophage‐mediated tumor cell lysis effects in vitro. MAbs C215, C163, and C245 were also tested in nude mice which had been inoculated with Colo‐205 cells. Tumor suppression was observed in mice injected with MAbs, supporting our ADMMC findings in vitro. Animals treated with MAbs had fewer and smaller tumors, and longer periods of latency between the inoculation of tumor cells and development of tumors, compared to mice sham‐treated with PBS. However, in a study of established tumors, C215 antibody did not suppress tumor growth. Serum collected from MAb‐treated mice promoted lysis of Colo‐205 cells in ADMMC assays while serum from sham‐treated mice did not.
SV40 transfection of human kidney epithelial cells and stability of chromosome 11
Authors: Poirier V. , Tyler S.J. , Brown K.W. , Shaw A.P.W. , Maitland N.J.
Published: April 2012

Simian virus 40 (SV40) transformation has been used in a variety of mammalian cells and has been shown to extend their life span. We therefore decided to apply these results to normal kidney and tumoral cells derived from Wilms' patients. Wilms' tumour, a nephroblastoma which presents in early childhood, has been linked to deletions and rearrangements in chromosome 11. Analysis of gene structure in the 11p13 locus involved in the development of the tumour has been restricted by the very short life‐span of the tumoral cells in vitro. We transfected normal kidney WT/NK, tumoral WT/T cells and human foetal kidney HFK cells with 2 SV40‐derived plasmids SV3neo (pBR322‐SV40‐containing neomycin bacterial gene) and SVori– (pMK‐origin mutated SV40). We isolated a high number of SV40‐transfected cell lines. The efficiency of transfection appeared to be extremely low in WT/T cells compared with HFK and even WT/NK. The life span of the cell lines was increased in relation to their untransfected homologues. However, in all of the cell lines except 3, senescence occurred, after crisis step or not. We looked at different markers associated with SV40 transformation of mammalian cells and specifically with the presence of SV40 T antigen in the cells and its consequences: AIG, tumorigenicity, expression and insertion in genomic DNA of SV40 T antigen. Genetic studies involving karyotypic and restriction fragment length polymorphism (RFLP) analysis demonstrated that, despite a frequent pseudo‐diploidy, the cell lines derived have conserved the 11p13 locus.
Autoimmune expression of a cytoplasmic protein p60 in mice bearing metastasizing SV40‐transformed tumors
Authors: Manneck Hans E. , Pfaff Martin , Anderer F. Alfred
Published: April 2012

In STU mice bearing metastasizing SV40‐transformed 51A‐232B‐M tumors, an immune response against a cellular 60kDa protein (p60) developed in about 50% of the tumor‐bearing animals, in addition to the response against SV40 large T‐antigen and cellular protein p53. The anti‐p60 auto‐immune response could be observed as early as 11 days after tumor challenge and was strictly linked with metastatic spread but was not a prerequisite for metastasis. Anti‐p60 antibodies could not be detected in sera of animals bearing metastasizing Rous‐sarcoma virus‐transformed or methylcholanthrene‐induced tumors, or in sera from human cancer patients with clinically confirmed metastatic spread. The anti‐p60 auto‐antibodies showed a broad cross‐reactivity against components of similar size in a great number of cell lines of various species and in normal mouse tissue. The p60 auto‐antigen is a cytoplasmic protein which is neither phosphorylated nor glycosylated in vivo. Immunoblotting performed with fresh cell lysates under non‐reducing conditions using tumor‐bearer sera revealed a diffuse p60 double band, but under reducing conditions only one sharp p60 band was observed. The reaction of p60 with anti‐p60 auto‐antibodies could be completely blocked by pre‐treatment of fresh cell lysates with N‐ethylmaleimide or p‐chloromercuriphenyl sulfonate, or by oxidation in air prior to immunoblotting, indicating that the anti‐p60 autoimmune response was directed against an epitope sensitive to SH‐group‐blocking reagents. Immunofluorescence studies with tumor‐bearer sera showed only a very weak cytoplasmic fluorescence, possibly due to the nature of the p60 SH‐groups in situ being masked. Immunoprecipitates with monoclonal antibodies against SV40 large T‐antigen and p53 obtained from fresh cell lysates of SV40‐transformed tumor cells contained no associated p60 auto‐antigen. The p60 auto‐antigen was purified from tumor cell homogenates with an enrichment factor of about 2,000; its iso‐electric point is at Ph 6.8. Determination of the biological half‐life of p60 yielded a value of about 28 hr. The p60 auto‐antibodies in pools of tumor‐bearer sera taken at day 40 after tumor challenge all belonged to the IgG1 subclass.
Growth and metastasis of human tumors in nude mice following tumor‐cell inoculation into a vascularized polyurethane sponge matrix
Authors: Thiede K. , Momburg F. , Zangemeister U. , Schlag P. , Schirrmacher V.
Published: April 2012

Growth and metastasis of human tumor cells in immunodeficient nude mice were improved when tumor cells were inoculated within a vascularized artificial polyurethane sponge matrix. The sponges had been implanted 7–10 days earlier and were vascularized at the time of cell injection. All cell lines tested, including colon carcinoma‐derived lines from primary tumors (HT29, PT3 and PT4) or from liver metastasis (LM3), and a metastatic variant from a melanoma (MeWo‐Met) grew in a high percentage (78–94%) of the inoculated sponge grafts. When growth in sponge grafts is compared with growth at a subcutaneous site, the sponge matrix appears to increase tumorigenicity, at least for some cell lines. Regular formation of metastases was observed when cells had been injected into sponges. Most metastases were found in a second sponge graft implanted at a contralateral site, but some were also found at other s.c. sites. In vivo depletion of NK cells by pre‐treatment with cyclophosphamide could not further enhance the formation of metastasis. Tumor cells from fresh surgical specimens could be propagated in sponge matrix grafts and subsequently established as cell lines in tissue culture.
Relationship between cellular adhesiveness and metastatic activity in polyomavirus‐transformed FR3T3 rat cell lines
Authors: Leung‐Tack Jeanne , Capo Christian , De Lapeyrière Odile , Benoliel Anne‐Marie , Arnaud Danielle , Bongrand Pierre
Published: April 2012

A series of polyomavirus‐transformed rat cells with varying tumorigenic potential were tested for biophysical parameters possibly related to metastatic properties: adhesive capacity and strength of adhesion to different substrates (laminin, fibronectin and albumin), cell deformability and spreading. Two groups of cell lines were defined according to their higher or lower adhesive capacity. Adhesivity did not appear to be related to cell deformability and spreading. A weak correlation was suggested between low adhesivity and high metastatic potential. A selection method was devised to separate cell samples into 3 subpopulations with different adhesive strength. Two cell lines, originally different, were chosen for this study: Py‐tsa A25 cells were less adherent and highly metastatic, and Py‐WTA2 cells were more adherent and less metastatic. After s.c. inoculation into syngeneic Fisher rats, the 3 selected subpopulations of the 2 cell lines induced pulmonary nodules to varying degrees, but only the less adherent ones were able to induce visceral metastasis located in stomach and intestine. In this case, animal survival time was 30% lower than for the highly adherent selected cells. After 10 culture passages, the same subpopulations were able to metastasize only in the lungs. However, when the selection procedure was repeated, the less adherent cells were again able to yield visceral nodules. Tumorigenicity remained unchanged in all cases. Study of cell dissemination and arrest in vivo showed a rapid targeting of labelled tumor cells toward lungs and stomach 5 hr after intradermal injection, where they remained up to 72 hr. More adherent cells displayed delayed localization after injection (24 hr) and radioactivity decreased more rapidly.
HOW RELIABLE ARE DE FACTO EXCHANGE RATE REGIME CLASSIFICATIONS?
Authors: Eichengreen Barry , Razo‐Garcia Raul
Published: April 2012

We analyze disagreements over de facto exchange‐rate‐regime classifications using three popular de facto regime data series. While there is a moderate degree of concurrence across classifications, disagreements are not uncommon, and they are not random. They are most prevalent in middle‐income countries (emerging markets) and low‐income (developing) countries as opposed to advanced economies. They are most prevalent for countries with well‐developed financial markets, low reserves and open capital accounts. This suggests caution when attempting to relate the exchange rate regime to financial development, the openness of the financial account, and reserve management and accumulation decisions. Copyright © 2012 John Wiley & Sons, Ltd.
Cell‐adhesive thermogelling PNIPAAm/hyaluronic acid cell delivery hydrogels for potential application as minimally invasive retinal therapeutics
Authors: Mazumder M. A. Jafar , Fitzpatrick Scott D. , Muirhead Ben , Sheardown Heather
Published: April 2012

Copolymers of N‐isopropylacrylamide (NIPAAm) and acrylic acid N‐hydroxysuccinimide (NAS) were synthesized via free radical polymerization and conjugated with amine‐functionalized hyaluronic acid (HA) and cell adhesive RGDS peptides. These novel copolymers were designed to facilitate noninvasive delivery of a liquid suspension of cells into the delicate subretinal space for treatment of retinal degenerative diseases such as age‐related macular degeneration (AMD) and diabetic retinopathy. The various synthesized copolymers all displayed subphysiological phase transition temperatures, thereby allowing temperature‐induced scaffold formation and subsequent entrapment of transplanted cells within an adhesive support matrix. Successful grafting of HA and RGDS peptides were confirmed with Fourier Transform Infrared (FTIR) spectroscopy and quantified with 1H Nuclear Magnetic Resonance (NMR) spectroscopy. All copolymers demonstrated excellent compatibility with retinal pigment epithelial (RPE) cells in culture and minimal host response was observed following subcutaneous implantation into hairless SKH1‐E mice (strain code 447). © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A 2012.
Heparin‐modified dendrimer crosslinked collagen matrices for the delivery of heparin‐binding epidermal growth factor
Authors: Princz M.A. , Sheardown H.
Published: April 2012

A tissue engineered corneal equivalent (TECEs) requires host integration to achieve adequate anchorage and long‐term device stability. Corneal integration through epithelialization and stromal integration can be manipulated by growth factors. We investigated the potential of heparin‐binding epidermal growth factor (HB‐EGF) for mediating interactions with human corneal epithelial cells (HCEC) and compared its efficacy to epidermal growth factor (EGF)in vitro. Furthermore, we utilized heparinized dendrimer crosslinked collagen gels, intended for use as TECE, for delivery of HB‐EGF in a sustained manner. HCEC were exposed to HB‐EGF at varying concentrations between 0.1 and 1000 ng/mL. Cell proliferation increased with growth factor concentration up to a concentration of 50 ng/mL, suggesting growth factor receptor down‐regulation at higher HB‐EGF concentrations. Response to HB‐EGF was comparable to EGF at low concentrations of 0.1 and 1 ng/mL but at a concentration of 10 ng/mL, HB‐EGF induced significantly better proliferation than EGF. Proliferation was found to be dependent on the initial seeding density. Heparinized dendrimer crosslinked collagen (CHG) gels were capable of HB‐EGF uptake, which was influenced by heparin concentration within the gel, growth factor concentration and exposure time to the growth factor. HB‐EGF release followed first order kinetics, with ∼90% of the growth factor released after 2 weeks. Growth factor stability was verified within vitroHCEC culture studies. Bioavailability was maintained in the gels through heparin interaction. Overall, HB‐EGF induced proliferation of HCECin vitroand can be released from heparinized collagen gels making it potentially suitable for promoting epithelialization of TECEs. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A 2012.
Does the tissue engineering architecture of poly(3‐hydroxybutyrate) scaffold affects cell–material interactions?
Authors: Masaeli Elahe , Morshed Mohammad , Rasekhian Parsa , Karbasi Saeed , Karbalaie Khadije , Karamali Fereshte , Abedi Daryoush , Razavi Shahnaz , Jafarian‐Dehkordi Abbas , Nasr‐Esfahani Mohammad Hossein , Baharvand Hossein
Published: April 2012

A critical element in tissue engineering involves the fabrication of a three‐dimensional scaffold. The scaffold provides a space for new tissue formation, supports cellular ingrowth, and proliferation and mimics many roles of the extracellular matrix. Poly(3‐hydroxybutyrate) (PHB) is the most thoroughly investigated member of the polyhydroxyalkanoates (PHAs) family that has various degrees of biocompatibility and biodegradability for tissue engineering applications. In this study, we fabricated PHB scaffolds by utilizing electrospinning and salt‐leaching procedures. The behavior of monkey epithelial kidney cells (Vero) and mouse mesenchymal stem cells (mMSCs) on these scaffolds was compared by the MTS assay and scanning electron microscopy. Additionally, this study investigated the mechanical and physical properties of these scaffolds by measuring tensile strength and modulus, dynamic contact angle and porosity. According to our results, the salt‐leached scaffolds showed more wettability and permeability, but inferior mechanical properties when compared with nanofibrous scaffolds. In terms of cell response, salt‐leached scaffolds showed enhanced Vero cell proliferation, whereas both scaffolds responded similarly in the case of mMSCs proliferation. In brief, nanofibrous scaffolds can be a better substrate for cell attachment and morphology. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A 2012.
A novel method to fabricate thermoresponsive microstructures with improved cell attachment/detachment properties
Authors: He Xiao‐Ling , Nie Ping‐Ping , Chen Bi‐Zhou , Li Xiang‐Xu , Chen Li , Guo Gang , Zhang Rui
Published: April 2012

A novel, simple, and rapid method to fabricate thermoresponsive micropatterned substrate for cell adhesion, growth, and thermally induced detachment was developed. Thermoresponsive polymer, poly(N‐isopropylacrylamide) (PNIPAAm), was grafted onto the surface of polystyrene (PS) film with microstructure by plasma‐induced graft polymerization technique. The thermoresponsive micropatterned films were characterized by attenuated total reflectance‐Fourier transform infrared (ATR‐FTIR) spectroscopy, hydrogen nuclear magnetic resonance (1H NMR) spectroscopy, X‐ray photoelectron spectroscopy (XPS) and scanning electron microscope (SEM). These results indicated that the grafting ratio of PNIPAAm increased with increasing roughness of PS film. However, the microstructures on the substrate were not affected by grafted PNIPAAm. The optimal grafting conditions, such as plasma treatment time, monomer concentration, graft polymerization time, and graft medium were investigated. The thermoresponsive micropatterned films were investigated with the fibroblast cell (L929) adhesion, proliferation, and thermally induced detachment assay. The microstructure on the thermoresponsive micropatterned substrate facilitated cell adhesion above the lower critical solution temperature (LCST) of PNIPAAm and cell detachment below the LCST. Moreover, it can be used to regulate cell organization and tissue growth. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A 2012.
Modulation of cellular responses on engineered polyurethane implants
Authors: Khandwekar Anand , Rho Cho K.
Published: April 2012

An in vivo rat cage implant system was used to study the effect of polyurethane surface chemistries on protein adsorption, macrophage adhesion, foreign‐body giant cell formation (FBGCs), cellular apoptosis, and cytokine response. Polyurethanes with zwitterionic, anionic, and cationic chemistries were developed. The changes in the surface topography of the materials were determined using atomic force microscopy and the wettability by dynamic contact angle measurements. The in vitro protein adsorption studies revealed higher protein adsorption on cationic surfaces when compared with the base, while adsorption was significantly reduced on zwitterionic (**p < 0.01) and anionic (*p < 0.05) polyurethanes. Analysis of the exudates surrounding the materials revealed no differences between surfaces in the types or levels of cells present. Conversely, the proportion of adherent cells undergoing apoptosis, as determined by annexin V‐FITC staining, increased significantly on anionic followed by zwitterionic surfaces (60 + 5.0 and 38 + 3.7%) when compared with the base. Additionally, zwitterionic and anionic substrates provided decreased rates of macrophage adhesion and fusion into FBGCs, whereas cationic surfaces promoted macrophage adhesion and FBGC formation. Visualization of the F‐actin cytoskeleton by Alexa Fluor 488 phalloidin showed a significant delay in the cytoskeletal fusion response on zwitterionic and the anionic surfaces. The real‐time polymerase chain reaction (PCR) analysis of proinflammatory cytokines (tumor necrosis factor (TNF)‐α and interleukin (IL)‐10) and pro‐wound healing cytokines (IL‐4 and TGF‐β) revealed differential cytokine responses. Cationic substrates that triggered stimulation of TNF‐α and IL‐4 were associated with more spread cells and higher FBGCs, whereas zwitterionic and anionic substrates that suppressed these cytokines levels were associated with less spread cells and few FBGCs. These studies have revealed that zwitterionic and anionic polyurethane surface chemistries can not only reduce nonspecific adhesion, fusion, and inflammatory events but also effectively promote cellular apoptosis in vivo. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 100A: 2211–2222, 2012.
Stabilization of collagen tissues by photocrosslinking
Authors: Vashi Aditya V. , Werkmeister Jerome A. , Vuocolo Tony , Elvin Christopher M. , Ramshaw John A. M.
Published: April 2012

Photocrosslinking, using 2 mMRuII(bpy)3Cl2and various concentrations of sodium persulfate with irradiation by blue light, ∼455 nm, has been shown to be a rapid and effective method for crosslinking various tissues: tendon, amnion membrane, pericardium, and heart valve leaflet. The presence of new crosslinking was demonstrated by the increase in the shrinkage temperature of these tissues. In all the cases, increase in the shrinkage temperatures were seen, although at higher sodium persulfate concentrations, for example, 100 mM, both with and without the RuII(bpy)3Cl2catalyst, some degradation of the collagenous tissues was found. The effectiveness of this photocrosslinking method when used with tissues was also shown through the increase in the break strength of tissues after crosslinking, and by the reduction of protein that could be extracted by urea. In solution studies, dityrosine has been shown to be formed during photocrosslinking. With tissues, Western blotting showed the presence of new dityrosine crosslinked proteins. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 100A: 2239–2243, 2012.
Daily parathyroid hormone 1-34 replacement therapy for hypoparathyroidism induces marked changes in bone turnover and structure
Authors: Gafni Rachel I , Brahim Jaime S , Andreopoulou Panagiota , Bhattacharyya Nisan , Kelly Marilyn H , Brillante Beth A , Reynolds James C , Zhou Hua , Dempster David W , Collins Michael T
Published: April 2012

Parathyroid hormone (PTH) has variable actions on bone. Chronically increased PTH is catabolic and leads to osteoporosis; yet intermittent administration is anabolic and increases bone mass. PTH deficiency is associated with decreased bone remodeling and increased bone mass. However, the effects of PTH replacement therapy on bone in hypoparathyroidism are not well known. We discontinued calcitriol therapy and treated 5 hypoparathyroid subjects (2 adults and 3 adolescents) with synthetic human PTH 1-34 (hPTH 1-34), injected two to three times daily for 18 months, with doses individualized to maintain serum calcium at 1.9 to 2.25 mmol/L. Biochemical markers and bone mineral density (BMD) were assessed every 6 months; iliac-crest biopsies were performed before and after 1 year of treatment. hPTH 1-34 therapy significantly increased bone markers to supranormal levels. Histomorphometry revealed that treatment dramatically increased cancellous bone volume and trabecular number and decreased trabecular separation. Changes in trabecular width were variable, suggesting that the increase in trabecular number was due to the observed intratrabecular tunneling. Cortical width remained unchanged; however, hPTH 1-34 treatment increased cortical porosity. Cancellous bone remodeling was also stimulated, inducing significant changes in osteoid, mineralizing surface, and bone formation rate. Similar changes were seen in endocortical and intracortical remodeling. BMD Z-scores were unchanged at the spine and femoral neck. Total hip Z-scores increased; however, total body BMD Z-scores decreased during the first 6 months of treatment and then stabilized, remaining significantly decreased compared to baseline. Radial Z-scores also decreased with treatment; this was most pronounced in the growing adolescent. Daily hPTH 1-34 therapy for hypoparathyroidism stimulated bone turnover, increased bone volume, and altered bone structure in the iliac crest. These findings suggest that treatment with hPTH 1-34 in hypoparathyroid adults and adolescents has varying effects in the different skeletal compartments, leading to an increase in trabecular bone and an apparent trabecularization of cortical bone. Published 2012 American Society for Bone and Mineral Research. This article is a US Government work and, as such, is in the public domain in the United States of America.
Repression of osteocyte Wnt/β-catenin signaling is an early event in the progression of renal osteodystrophy
Authors: Sabbagh Yves , Graciolli Fabiana Giorgeti , O'Brien Stephen , Tang Wen , dos Reis Luciene Machado , Ryan Susan , Phillips Lucy , Boulanger Joseph , Song Wenping , Bracken Christina , Liu Shiguang , Ledbetter Steven , Dechow Paul , Canziani Maria Eugenia F , Carvalho Aluizio B , Jorgetti Vanda , Moyses Rosa MA , Schiavi Susan C
Published: April 2012

Chronic kidney disease–mineral bone disorder (CKD-MBD) is defined by abnormalities in mineral and hormone metabolism, bone histomorphometric changes, and/or the presence of soft-tissue calcification. Emerging evidence suggests that features of CKD-MBD may occur early in disease progression and are associated with changes in osteocyte function. To identify early changes in bone, we utilized the jck mouse, a genetic model of polycystic kidney disease that exhibits progressive renal disease. At 6 weeks of age, jck mice have normal renal function and no evidence of bone disease but exhibit continual decline in renal function and death by 20 weeks of age, when approximately 40% to 60% of them have vascular calcification. Temporal changes in serum parameters were identified in jck relative to wild-type mice from 6 through 18 weeks of age and were subsequently shown to largely mirror serum changes commonly associated with clinical CKD-MBD. Bone histomorphometry revealed progressive changes associated with increased osteoclast activity and elevated bone formation relative to wild-type mice. To capture the early molecular and cellular events in the progression of CKD-MBD we examined cell-specific pathways associated with bone remodeling at the protein and/or gene expression level. Importantly, a steady increase in the number of cells expressing phosphor-Ser33/37-β-catenin was observed both in mouse and human bones. Overall repression of Wnt/β-catenin signaling within osteocytes occurred in conjunction with increased expression of Wnt antagonists (SOST and sFRP4) and genes associated with osteoclast activity, including receptor activator of NF-κB ligand (RANKL). The resulting increase in the RANKL/osteoprotegerin (OPG) ratio correlated with increased osteoclast activity. In late-stage disease, an apparent repression of genes associated with osteoblast function was observed. These data confirm that jck mice develop progressive biochemical changes in CKD-MBD and suggest that repression of the Wnt/β-catenin pathway is involved in the pathogenesis of renal osteodystrophy. © 2012 American Society for Bone and Mineral Research.
DICAM inhibits osteoclast differentiation through attenuation of the integrin αVβ3 pathway
Authors: Jung Youn-Kwan , Han Seung-Woo , Kim Gun-Woo , Jeong Jae-Hwan , Kim Hyun-Ju , Choi Je-Yong
Published: April 2012

Dual immunoglobulin (Ig) domain-containing adhesion molecule (DICAM) is involved in cell–cell adhesion through a heterophilic interaction with αVβ3 integrin, which suggests that DICAM may participate in osteoclast differentiation. DICAM was localized in the plasma membrane of RAW264.7 and THP-1 cells, and its expression gradually increased during osteoclastogenesis in mouse bone marrow-derived macrophages (BMMs) treated with receptor activator of nuclear factor κ-B ligand (RANKL) and macrophage colony-stimulating factor (M-CSF). Forced expression of DICAM in BMMs and RAW264.7 cells blocked the generation of tartrate-resistant acid phosphatase (TRAP)-positive osteoclasts. Conversely, knockdown of DICAM by small hairpin RNA (shRNA) increased osteoclast formation in RAW264.7 cells. DICAM-mediated suppression of osteoclast differentiation was in part due to the inhibition of the p38 mitogen-activated protein (MAP) kinase pathway, which was corroborated by a decrease in the expression of c-Fos and nuclear factor of activated T cells (NFAT)c1. Mechanistically, DICAM directly interacted with integrin β3, which inhibited heterodimerization between integrin αV and β3. Exogenous expression of integrin β3 or high-dose M-CSF rescued DICAM-mediated inhibition of osteoclastogenesis, suggesting crosstalk between the integrin β3 and c-Fms pathways. Finally, recombinant DICAM ectodomain suppressed the RANKL- and M-CSF–induced osteoclastogenesis of BMMs. Collectively, these results indicate that DICAM acts as a negative regulator of osteoclast differentiation by suppressing the integrin αVβ3 pathway. © 2012 American Society for Bone and Mineral Research.
The effect of surface treatments on the microroughness of laser‐sintered and vacuum‐cast base metal alloys for dental prosthetic frameworks
Authors: Castillo‐Oyagüe Raquel , Osorio Raquel , Osorio Estrella , Sánchez‐aguilera Fátima , Toledano Manuel
Published: April 2012

This study aimed to evaluate the effect of four chemomechanical surface treatments on the surface average microroughness and profile of laser‐sintered and vacuum‐cast dental prosthetic structures. Square‐shaped blocks (10 mm × 10 mm × 1.5 mm) were prepared as follows: (1) laser‐sintered CoCr (L) (ST2724G); (2) cast CoCr (C) (Gemium‐cn); and (3) cast NiCrTi (T) (Tilite). Specimens of each alloy group were randomly divided into five subgroups (n = 10 each), depending on the conditioning method used: (1) no treatment (control); (2) sandblasting (125 μm Al2O3‐particles); (3) silica coating (50 μm silica‐modified Al2O3‐particles); (4) oxidation; and (5) oxidation plus opacification. Subgroups 2 and 3 represent “inner” pretreatments proposed for ceramometal restorations to improve the metal surface area available for luting cements. Subgroups 4 and 5 are the “outer” pretreatments required for bonding the aesthetic veneering ceramics to the underlying metal frameworks. Average surface roughness (Ra/μm) was determined using a surface profilometer. Data were analyzed by two‐way ANOVA and Student–Newman–Keuls tests (α = 0.05). Metal surface topography was SEM‐analyzed. Despite the inner pretreatment applied, L samples resulted in the highest microroughness (P < 0.001), whereas sandblasting produced a surface‐smoothing effect in cast specimens. After oxidation, a significant increase in surface roughness occurred in all groups compared with controls, L specimens being the roughest (P < 0.001). Opacification caused a flattening effect of all oxidized structures; all opacified groups resulting in similar microroughness. Laser sintering of CoCr enhances the roughness of metal structures, which may improve the frameworks' microretention of the cements, and of the opaquer before the copings are veneered with the aesthetic ceramics. Microsc. Res. Tech. 75:1206–1212, 2012. © 2012 Wiley Periodicals, Inc.
Morphological observations of ampullae of lorenzini in Squatina guggenheim and S. occulta (chondrichthyes, elasmobranchii, squatinidae)
Authors: Schäfer Bárbara Tavares , Malavasi Carlos Eduardo , Favaron Phelipe Oliveira , Ambrósio Carlos Eduardo , Miglino Maria Angelica , De Amorim Alberto Ferreira , Rici Rose Eli Grassi
Published: April 2012

We have conducted a morphological study of the ampullae of Lorenzini on two shark species from Squatina Genus. In both species, S. guggenheim and S. occulta, the ampullae were observed like small pores scattered in the head region similar to other species of the Chondrichthyes Class. However, differently of the other species a greatest density of ampullae of Lorenzini was observed along of the body surface. After fixation using 10% formaldehyde, the ampullae were removed and processed for light and scanning electron microscopy. Macroscopically, the two shark species differed by the presence of dorsal spines that appeared from the head to the first dorsal fin in S. guggenheim and were absent in S. occulta. Microscopically, there were no differences between the ampullae of Lorenzini channels in these two species. The wall of the ampulla was formed by a simple squamous epithelium. Bands of connective tissue, hyaline cartilage and collagen fibers were found between the ampulla and the skeletal striated muscle layer. Nerve branches responsible for conducting signal pulses to the central nervous system were visible between the muscle and connective tissue layers. Using scanning electron microscopy and histological analysis, we found that the channels were twisted and positioned parallel to the skin. The inside of the channels contained a large amount of a gelatinous secretion composed by polysaccharides. Therefore, we conclude that the morphological combination of extended distribution of the ampullae of Lorenzini and the body shape may represent an adaptation of these species to their way of life. Microsc. Res. Tech. 75:1213–1217, 2012. © 2012 Wiley Periodicals, Inc.
Inhibition by morphine and its analogs of action potentials in adult rat dorsal root ganglion neurons
Authors: Mizuta Kotaro , Fujita Tsugumi , Kumamoto Eiichi
Published: April 2012

Although opioids inhibit action potential (AP) conduction in primary‐afferent fibers, this has not yet been fully examined. We investigated by using the sharp glass microelectrode technique how opioids (morphine, codeine, and ethylmorphine) affect APs recorded from adult rat dorsal root ganglion (DRG) neurons in response to sciatic nerve stimulation. The DRG neurons were classified into three types, Aα/β, Aδ, and C, according to AP characteristics, including the fiber conduction velocity (CV) of the neuron. AP of the Aα/β neuron was reduced in peak amplitude by each of the opioids in a reversible and concentration‐dependent manner. The potency sequence was ethylmorphine > codeine = morphine (IC50 = 0.70, 2.5, and 2.9 mM, respectively), indicating that this AP inhibition is related to the chemical structure of the opioid. Each of the Aδ and C neuron APs was also inhibited by the opioids; ethylmorphine had a tendency to inhibit APs more effectively than codeine and morphine. This inhibition was variable in extent among neurons and was either comparable to or greater than that of the Aα/β neuron AP. The opioid‐induced AP inhibitions were unaffected by nonspecific opioid‐receptor antagonist naloxone; opioid‐receptor agonists did not affect APs. In conclusion, the opioids inhibited APs in DRG neurons without opioid‐receptor activation; this inhibition was different among neurons having different primary‐afferent fiber CVs and also among the three kinds of opioid. The inhibition by opioid of primary‐afferentfiber AP conduction is suggested to be distinct in extent among fibers conveying distinct types of nociceptive information. © 2012 Wiley Periodicals, Inc.
Immobilization of white‐tailed deer with telazol, ketamine, and xylazine, and evaluation of antagonists
Authors: Monteith Kevin L. , Monteith Kyle B. , Delger Joshua A. , Schmitz Lowell E. , Brinkman Todd J. , Deperno Christopher S. , Jenks Jonathan A.
Published: April 2012

Telazol–xylazine and ketamine–xylazine are versatile and safe drug combinations that are used frequently for chemical immobilization of cervids. Although neither combination consistently offers rapid induction and recovery, we hypothesized that a combination of Telazol, ketamine, and xylazine (TKX) would provide a safe and effective alternative for immobilization of white‐tailed deer (Odocoileus virginianus). During a 2‐stage study, we evaluated the effectiveness of yohimbine and tolazoline as alpha2‐adrenergic antagonists (2005–2006), and characterized the factors that affected chemical immobilization of male deer with a targeted dose of telazol (2.20 mg/kg), ketamine (1.76 mg/kg), and xylazine (0.44 mg/kg), using explosive‐charged darts (2007–2010). During the first stage, we randomly assigned deer to antagonist treatments, including a control group that did not receive an antagonist (n = 8), a tolazoline (4 mg/kg) treatment (n = 16), and a yohimbine (0.11 mg/kg) treatment (n = 15). Recovery times $({\bar {x}}\pm {\rm SE)}$ were longer (P = 0.0013) for control (150.6 ± 21.7 min) and yohimbine (74.5 ± 13.1 min), compared with tolazoline (12.5 ± 12.3 min). Tolazoline resulted in faster and more complete recovery compared with the frequent incomplete antagonism and ataxia observed with yohimbine. During the second stage, 56 immobilization events (2007–2010) with TKX yielded a mean induction time of 7.8 minutes (SE = 0.44). Repeated‐measures analyses indicated that induction and recovery were affected by body weight, with larger males taking longer to become recumbent (P = 0.08), but they recovered more rapidly (P = 0.003) following administration of tolazoline. Physiological parameters we measured under anesthesia were within normal ranges for white‐tailed deer; however, initial temperature was higher (β = −0.86) for younger males (P = 0.014). Final physiological parameters were closely related to initial measurements, with rectal temperature being the most preserved (β = 0.90); heart and respiration rate declined (β < 0.60) during anesthesia. Our results indicate that TKX may be useful for chemically immobilizing white‐tailed deer, and we recommend tolazoline as an antagonist for xylazine. © 2012 The Wildlife Society.
Influence of forest structure on the abundance of snowshoe hares in western Wyoming
Authors: Berg Nathan D. , Gese Eric M. , Squires John R. , Aubry Lise M.
Published: April 2012

Snowshoe hares (Lepus americanus) are a primary prey species for Canada lynx (Lynx canadensis) in western North America. Lynx management plans require knowledge of potential prey distribution and abundance in the western United States. Whether even‐aged regenerating forests or multi‐storied forests contain more snowshoe hares is currently unknown. During 2006–2008, we estimated snowshoe hare density in 3 classes of 30–70‐year‐old lodgepole pine (Pinus contorta) and 4 classes of late seral multi‐storied forest with a spruce (Picea engelmannii)‐fir (Abies lasiocarpa) component in the Bridger‐Teton National Forest, Wyoming. We recorded physiographic variables and forest structure characteristics to understand how these factors influence abundance of snowshoe hares. In many instances, snowshoe hares were more abundant in late seral multi‐storied forests than regenerating even‐aged forests. Forest attributes predicting hare abundance were often more prevalent in multi‐storied forests. Late seral multi‐storied forests with a spruce–fir component and dense horizontal cover, as well as 30–70‐year‐old lodgepole pine with high stem density, were disproportionately influential in explaining snowshoe hare densities in western Wyoming. In order to promote improved habitat conditions for snowshoe hares in this region, management agencies should consider shifting their focus towards maintaining, enhancing, and promoting multi‐storied forests with dense horizontal cover, as well as developing 30–70‐year‐old lodgepole pine stands with high stem density that structurally mimic multi‐storied forests. © 2012 The Wildlife Society.
Effect of winter flooding on mass and gross energy of bottomland hardwood acorns
Authors: Leach Alan G. , Straub Jacob N. , Kaminski Richard M. , Ezell Andrew W. , Hawkins Tracy S. , Leininger Theodor D.
Published: April 2012

Decomposition of red oak acorns (Quercus spp.; Section Erythrobalanus) could decrease forage biomass and gross energy (GE) available to wintering ducks from acorns. We estimated changes in mass and GE for 3 species of red oak acorns in flooded and non‐flooded bottomland hardwood forests in Mississippi during winter 2009–2010. Mass loss of acorns was ≤8.1% and reduction in GE ≤0.03 kcal/g after exposure for 90 days. These small changes in mass and GE of red oak acorns would have minimal effect on carrying capacity of bottomland hardwood forests for ducks. © 2012 The Wildlife Society.
Influence of minor components on fat crystallization
Authors: Talbot Geoff , Smith Kevin , Bhaggan Krish
Published: April 2012

Crystallization in fats is of fundamental importance in the production and consumption of fats per se and of food and home and personal care (HPC) products in which fats form a major part. While crystallization of fats as such has been extensively reviewed over the past decade there has been less emphasis on the role of minor components. A review by Smith et al. [1] redressed this; this article is based on that review.
On the asymptotic behavior of a linear viscoelastic fluid
Authors: Fabrizio Mauro , Lazzari Barbara , Nibbi Roberta
Published: April 2012

We study the asymptotic behavior of an incompressible viscoelastic fluid and prove that the temporal decay of the energy is similar to one of the memory kernel. The innovative aspect of this research lies in considering the evolutive problem with non‐zero external sources and/or initial histories. Copyright © 2012 John Wiley & Sons, Ltd.