bluuebunny/crossref_metadata_2025 huggingface dataset:
Treatment of a commercial, machined surface titanium implant with H2SO4/H2O2 enhances contact osteogenesis
Authors: Tavares Marconi Gonzaga , Tambasco de Oliveira Paulo , Nanci Antonio , Hawthorne Ana Carolina , Rosa Adalberto Luiz , Xavier Samuel Porfírio
Published: May 2007

Background: It has recently been reported that controlled chemical oxidation of titanium (Ti) with sulfuric acid (H2SO4)/hydrogen peroxide (H2O2) significantly influences the early stages of in vitro osteogenesis. The aim of this study was to evaluate whether this chemical treatment can also influence in vivo bone formation.

Material and methods: Ti implants (Mk III) were etched with H2SO4/H2O2 for 4 h at room temperature. Mandibular premolars were extracted in eight dogs and, after 3 months, three treated and three untreated implants were placed in each animal. At 3 and 8 weeks postimplantation, the animals were sacrificed, and the implants with surrounding bone were harvested, fixed with formaldehyde, and processed for embedding in LR White. Sections of bone with the implants were prepared, stained with Stevenel's blue and Alizarin red, and analyzed histomorphometrically for percentage of bone‐to‐implant contact (BIC), percentage of mineralized bone area between threads (BABT), and percentage of mineralized bone area within the mirror area (BAMA). Data were analyzed statistically using two‐way analysis of variance.

Results: Treated implants exhibited significantly more (P<0.05) BIC than control, untreated ones both at 3 (68.1% vs. 27.9%) and 8 weeks (73.5% vs. 14.7%) postimplantation. However, there was no difference in the BABT and BAMA. Histological analysis confirmed that, in most cases, new bone in contact with the implant formed in a direction away from it.

Conclusions: These data indicate that a controlled chemical oxidation of Ti implants significantly enhances contact osteogenesis and suggest that this treatment may be beneficial for early loading of implants.
Computer‐guided flapless placement and immediate loading of four conical screw‐type implants in the edentulous mandible
Authors: Wittwer Gert , Adeyemo Wasiu Lanre , Wagner Arne , Enislidis Georg
Published: May 2007

Aim:The aim of this prospective study was to evaluate the outcome of computer‐guided flapless placement and immediate loading of four conical screw‐type implants in the interforaminal region.

Patients and methods:From May to August 2003, 25 consecutive patients (m : f=16 : 9) with edentulous mandibles were included in the study. After transmucosal drilling with computer‐assisted navigation, four implants were placed in the interforaminal region. The lower dentures were converted and implants immediately loaded.

Results:One‐hundred implants were successfully placed. In two patients, all implants had to be submerged because of insufficient primary stability of one of the implants; another patient declined to receive immediate loading of implants after surgery and was lost to follow‐up. During follow‐up of the remaining 22 patients with 88 immediately loaded implants, loosening of four implants (4.5%) was seen in three patients. In these cases, immediate loading was terminated and all implants submerged; subsequently, two implants were lost in one patient, while the other two implants re‐osseointegrated. The cumulative survival and success rates of immediately loaded implants were 97.7% after 2 years. Prosthetic success was 100%.

Conclusion:Transmucosal computer‐assisted placement and immediate loading of mandibular implants is a high‐end approach to edentulism that provides excellent results while being minimally invasive.
Salivary gland parameters and clinical data related to the underlying disorder in patients with persisting xerostomia
Authors: Van Den Berg Ianthe , Pijpe Justin , Vissink Arjan
Published: May 2007

This study assessed salivary gland parameters and clinical data in patients referred to our clinic because of persisting xerostomia of unknown origin, in order to facilitate early diagnosis and recognition of the underlying disorder. Most patients were referred for diagnostic analysis of a possible Sjögren's syndrome (SS). A complete diagnostic work‐up was available in all patients (n = 176), including data on salivary gland function, saliva composition, sialography, salivary gland swelling, pattern of complaints, general health, and medication. Patients were diagnosed with SS (n = 62), sialosis (n = 45), sodium retention syndrome (n = 30), or medication‐induced xerostomia (n = 9). In 30 patients no disease related to salivary gland pathology was found. Unstimulated whole salivary flow was decreased in all patients, except in patients with sodium retention syndrome and in patients without salivary gland pathology. Submandibular/sublingual salivary flow was lowest in SS patients. SS and sialosis patients had increased salivary potassium concentrations, whereas only SS patients had increased sodium concentrations. About half of the sialosis patients mainly complained of persistent parotid gland swelling. Xerostomia‐inducing medication was used by most patients. It was concluded that gland‐specific sialometry and sialochemistry is useful in discriminating between the various disorders causing persisting xerostomia.
Plaque formation and lactic acid production after the use of amine fluoride/stannous fluoride mouthrinse
Authors: Gerardu Véronique A. M. , Buijs Mark , Van Loveren Cor , Ten Cate Jacob M.
Published: May 2007

The aim of this study was to determine the effects of 3 wk of daily rinsing with amine fluoride/stannous fluoride (AmF/SnF2) mouthrinse on plaque formation at buccal and interproximal sites, and on the acid production in plaque, in a randomized clinical trial with 30 participants. The amount of plaque was scored according to Turesky's modification of the Quigley and Hein index. Plaque samples were collected, before and after sucrose rinsing, from the buccal and interproximal surfaces of upper (pre)molars at two baseline visits and on days 2 and 7 after the discontinuation of 3 wk of daily rinsing. Metabolic acid ions were determined by capillary electrophoresis. The results at baseline showed higher lactic acid concentrations in resting interproximal plaque than in buccal plaque, and a higher acid production in response to sucrose challenge in buccal plaque than in interproximal plaque. After 3 wk of use of the AmF/SnF2 mouthrinse, no significant differences in plaque scores were observed, and the alleged reduction in acidogenicity of dental plaque was not significant on the second day after the last mouthrinse. We conclude that 3 wk of use of AmF/SnF2 rinse once daily does not result in a reduction of plaque formation or in a reduction of sucrose metabolism in buccal and interproximal plaque after discontinuing the rinse.
Intensity and extent of Oral Impacts on Daily Performances by type of self‐perceived oral problems
Authors: Bernabé Eduardo , Tsakos Georgios , Sheiham Aubrey
Published: May 2007

The objectives of this study were to determine the prevalence, intensity, and extent of the impacts caused by oral problems, and to compare their intensity and extent by the type of oral problem. Four of seven public schools linked to a Health Center in Lima, Peru, were randomly selected as clusters, and 805 11–12‐yr‐old children participated in the study (response rate: 89.1%). The Spanish (Peru) child version of the Oral Impact of Daily Performances (Child‐OIDP) was used to assess oral impacts. The prevalence of oral impacts was 82.0%. Eating was the daily performance most frequently impacted (48.0%). Among children with impacts, 24.8% reported impacts of severe to very severe intensity, and 73.2% reported impacts affecting between one and three daily performances. When the intensity and extent of the eight most frequently reported oral problems were compared, a statistically significant difference was found only for the extent but not for the intensity of the impacts. Oral impacts on daily performances were very common and relatively severe among the participating Peruvian children. The pattern of the impacts differed according to the type of self‐perceived oral problem. However, the differences were reflected in the extent, but not in the intensity, of the impacts.
Informatic and genomic analysis of melanocyte cDNA libraries as a resource for the study of melanocyte development and function
Authors: Baxter Laura L. , Hsu Benjamin J. , Umayam Lowell , Wolfsberg Tyra G. , Larson Denise M. , Frith Martin C. , Kawai Jun , Hayashizaki Yoshihide , Carninci Piero , Pavan William J.
Published: May 2007

As part of the RIKEN mouse encyclopedia project, two cDNA libraries were prepared from melanocyte‐derived cell lines, using techniques of full‐length clone selection and subtraction/normalization to enrich for rare transcripts. End sequencing showed that these libraries display over 83% complete coding sequence at the 5′ end and 96–97% complete coding sequence at the 3′ end. Evaluation of the libraries, derived from B16F10Y tumor cells and melan‐c cells, revealed that they contain clones for a majority of the genes previously demonstrated to function in melanocyte biology. Analysis of genomic locations for transcripts revealed that the distribution of melanocyte genes is non‐random throughout the genome. Three genomic regions identified that showed significant clustering of melanocyte‐expressed genes contain one or more genes previously shown to regulate melanocyte development or function. A catalog of genes expressed in these libraries is presented, providing a valuable resource of cDNA clones and sequence information that can be used for identification of new genes important for melanocyte development, function, and disease.
Evolutionary sequence comparison of the Mitf gene reveals novel conserved domains
Authors: Hallsson Jón Hallsteinn , Haflidadóttir Benedikta S. , Schepsky Alexander , Arnheiter Heinz , Steingrímsson Eiríkur
Published: May 2007

The microphthalmia‐associated transcription factor (MITF) is a member of the MYC family of basic helix–loop–helix leucine zipper transcription factors. The corresponding gene was initially discovered in the mouse based on mutations which affect the development of several different cell types, including melanocytes and retinal pigment epithelium cells. Subsequently, it was shown to be associated with deafness and hypo‐pigmentation disorders in humans. More recently, the gene has been shown to be critical in melanoma formation and to play a role in melanocyte stem cell maintenance. Thus, the mouse Mitf gene represents an important model system for the study of human disease as well as an interesting model for the study of transcription factor function in the organism. Here we use the evolutionary relationship of Mitf genes from numerous distantly related species, including vertebrates and invertebrates, to identify novel conserved domains in the Mitf protein and regions of possible functional importance in the 3′ untranslated region. We also characterize the nine different 5′ exons of the Mitf gene and identify a new 5′ exon in the Drosophila Mitf gene. Our analysis sheds new light on the conservation of the Mitf gene and protein and opens the door for further functional analysis.
Decrease in the number and apoptosis of alveolar bone osteoclasts in estrogen‐treated rats
Authors: Faloni A. P. S. , Sasso‐Cerri E. , Katchburian E. , Cerri P. S.
Published: May 2007

Background and Objective:  Bone is a mineralized tissue that is under the influence of several systemic, local and environmental factors. Among systemic factors, estrogen is a hormone well known for its inhibitory function on bone resorption. As alveolar bone of young rats undergoes continuous and intense remodeling to accommodate the growing and erupting tooth, it is a suitable in vivo model for using to study the possible action of estrogen on bone. Thus, in an attempt to investigate the possibility that estrogen may induce the death of osteoclasts, we examined the alveolar bone of estrogen‐treated rats.

Material and Methods:  Fifteen, 22‐d‐old female rats were divided into estrogen, sham and control groups. The estrogen group received estrogen and the sham group received corn oil used as the dilution vehicle. After 8 d, fragments containing alveolar bone were removed and processed for light microscopy and transmission electron microscopy. Sections were stained with hematoxylin and eosin and tartrate‐resistant acid phosphatase (TRAP)–an osteoclast marker. Quantitative analysis of the number of TRAP‐positive osteoclasts per mm of bone surface was carried out. For detecting apoptosis, sections were analyzed by the Terminal deoxynucleotidyl transferase‐mediated dUTP Nick‐End Labeling (TUNEL) method; TUNEL/TRAP combined methods were also used.

Results:  The number of TRAP‐positive osteoclasts per mm of bone surface was significantly reduced in the estrogen group compared with the sham and control groups. TRAP‐positive osteoclasts exhibiting TUNEL‐positive nuclei were observed only in the estrogen group. In addition, in the estrogen group the ultrastructural images revealed shrunken osteoclasts exhibiting nuclei with conspicuous and tortuous masses of condensed chromatin, typical of apoptosis.

Conclusion:  Our results reinforce the idea that estrogen inhibits bone resorption by promoting a reduction in the number of osteoclasts, thus indicating that this reduction may be, at least in part, a consequence of osteoclast apoptosis.
Stress‐Induced Retrotranslocation of Clusterin/ApoJ into the Cytosol
Authors: Nizard Philippe , Tetley Susanne , Le Dréan Yves , Watrin Tanguy , Le Goff Pascale , Wilson Mark R. , Michel Denis
Published: May 2007

Clusterin is a usually secreted glycoprotein with chaperone properties. Recently, it has been suggested that clusterin isoforms reside in the nuclear and cytosolic compartments of human cell types, where they can influence various cellular programs including DNA repair, transcription and apoptosis. Several mechanisms have been proposed to explain this atypical location, including alternative transcription initiation and alternative splicing. However, none of these have been unequivocally established as occurring in live cells. Here we provide direct experimental evidence that in live intact cells, under certain stress conditions, clusterin can evade the secretion pathway and reach the cytosol. This was demonstrated using several complementary approaches. Flow cytometry and selective permeabilization of U251 cell membranes with digitonin allowed detection of cytosolic clusterin in stressed U251 cells. In addition, a stringent enzymatic assay reliant upon the exclusively cytosolic deubiquitinase enzymes confirmed that clusterin synthesized with its hydrophobic secretion signal sequence can reach the cytosol of U251 cells. The retrotranslocation of clusterin is likely to occur through a mechanism similar to the endoplasmic reticulum (ER)‐associated protein degradation pathway and involves passage through the Golgi apparatus. We also report that the ER‐associated ubiquitin ligase Hrd1/synoviolin can interact with, and ubiquitinate clusterin. The possible biological functions of these novel behaviours of clusterin are discussed.
Craniofacial osseointegration
Authors: Granström G
Published: May 2007

In year 2007, 30 years have elapsed since the first patient was supplied with a craniofacial osseointegrated implant. The reason for implanting in this patient was a severe conductive hearing loss, which necessitated the use of a bone conduction hearing aid. By utilizing the possibility to transmit sound to the cochlea via direct bone conduction, a new era in audiology was established. Further applications of osseointegration in the craniofacial field is related to the rehabilitation of patients with defects from cancer therapy, malformations, traumatic amputations and burns. Specific fields of osseointegration in this respect are due to possible side effects from radiotherapy and chemotherapy that will affect osseointegration negatively. Other aspects are related to osseointegration in children. This review will focus on the knowledge gained during the first 30 years of craniofacial osseointegration.
Differential Extracellular Signal‐Regulated Kinases 1 and 2 Activation by the Angiotensin Type 1 Receptor Supports Distinct Phenotypes of Cardiac Myocytes
Authors: Aplin Mark , Christensen Gitte Lund , Schneider Mikael , Heydorn Arne , Gammeltoft Steen , Kjølbye Anne Louise , Sheikh Søren P. , Hansen Jakob Lerche
Published: May 2007

Abstract:  The angiotensin II (AngII) type 1 receptor (AT1R) is a seven‐transmembrane receptor well established to activate extracellular signal‐regulated kinases 1 and 2 (ERK1/2) by discrete G protein‐dependent and β‐arrestin2‐dependent pathways. The biological importance of this, however, remains obscure. Application of the modified analogue [Sar1, Ile4, Ile8]‐AngII ([SII] AngII) allowed us to dissect the two pathways of ERK1/2 activation in native cardiac myocytes. Although cytosol‐retained, the β‐arrestin2‐bound pool of ERK1/2 represents an active signalling component that phosphorylates p90 Ribosomal S6 Kinase, a ubiquitous and versatile mediator of ERK1/2 signal transduction. Moreover, the β‐arrestin2‐dependent ERK1/2 signal supports intact proliferation of cardiac myocytes. In contrast to Gq‐activated ERK1/2, and in keeping with its failure to translocate to the nucleus, the β‐arrestin2‐scaffolded pool of ERK1/2 does not phosphorylate the transcription factor Elk‐1, induces no increased transcription of the immediate‐early gene c‐Fos, and does not entail myocyte hypertrophy. These results clearly demonstrate the biological significance of differential signalling by the AT1R. The opportunity to separate desirable cardiac myocyte division from detrimental hypertrophy holds promise that novel pharmacological approaches will allow targeting of pathway‐specific actions.
Serum Cytokine Levels of Interleukin‐1β, ‐6, ‐8, Tumour Necrosis Factor‐α and Vascular Endothelial Growth Factor in Breast Cancer Patients Treated with Tamoxifen and Supplemented with Co‐Enzyme Q10, Riboflavin and Niacin
Authors: Premkumar Vummidi Giridhar , Yuvaraj Srinivasan , Vijayasarathy Kothandaraman , Gangadaran Sitthu Govindaswamy Dinakaran , Sachdanandam Panchanatham
Published: May 2007

Abstract: The prognostic significance of supplementing co‐enzyme Q10(CoQ10), riboflavin and niacin (CoRN) along with tamoxifen to breast cancer patients was evaluated by measuring the serum cytokine levels of interleukin (IL)‐1β, IL‐6, IL‐8, tumour necrosis factor α (TNF‐α) and vascular endothelial growth factor. In the present study, 84 breast cancer patients were randomized to receive a daily supplement of CoQ10100 mg, riboflavin 10 mg and niacin 50 mg, one dosage per day along with tamoxifen 10 mg twice a day. Serum cytokine levels were elevated in untreated breast cancer patients (Group II) and significantly reduced after tamoxifen therapy for more than 1 year (Group III). When group III breast cancer patients were supplemented with CoRN for 45 days (Group IV) and 90 days (Group V) along with tamoxifen, a significant reduction in cytokine levels were observed (P < 0.05). Such a decrease in serum cytokine levels after CoRN supplementation in breast cancer patients may suggest good prognosis and efficacy of the treatment, and might even offer protection from metastases and recurrence of cancer.
Compared Effect of Immunosuppressive Drugs Cyclosporine A and Rapamycin on Cholesterol Homeostasis Key Enzymes CYP27A1 and HMG‐CoA Reductase
Authors: Gueguen Yann , Ferrari Luc , Souidi Maâmar , Batt Anne‐Marie , Lutton Claude , Siest Gérard , Visvikis Sophie
Published: May 2007

Abstract:  Hyperlipidaemia, i.e. increase in total cholesterol and triglycerides, is a common side‐effect of the immunosuppressive drugs rapamycin (RAPA) and cyclosporine A (CsA), and is probably related to inhibition of the 27‐hydroxylation of cholesterol (acid pathway of bile acid biosynthesis). This might be one of the causes for the increase in plasma cholesterol, as 27‐hydroxycholesterol is a potent suppressor of 3‐hydroxy‐3‐methyl‐glutaryl‐CoA reductase (HMGR), a key enzyme of cholesterol synthesis. As the sterol 27‐hydroxylase (CYP27A1) inhibition by CsA is well known, we evaluated the effect of another immunosuppressive drug, RAPA, on this enzyme in HepG2 mitochondria, which confirmed the dose‐dependent inhibition of mitochondrial CYP27A1 by cyclosporine (10–20 µM), while the inhibition by RAPA required a higher dose (50–100 µM). Corresponding Ki was 10 µM for CsA (non‐competitive inhibition) and 110 µM for RAPA (competitive inhibition). Cotreatment with both immunosuppressive drugs showed an additive inhibitory effect on CYP27A1 activity. Later, we analysed the effect of these immunosuppressants on HMGR expression in HepG2 cells, and a dose‐dependent up‐regulation of HMGR gene expression was observed. The results suggest that RAPA and CsA are both inhibitors of CYP27A1 activity with slightly different mechanisms and that they may accordingly increase HMGR expression.
Effect of Lycopene on Nephrotoxicity Induced by Mercuric Chloride in Rats
Authors: Augusti Paula R. , Conterato Greicy M. M. , Somacal Sabrina , Einsfeld Lídia , Ramos Adriano T. , Hosomi Fernando Y. M. , Graça Dominguita L. , Emanuelli Tatiana
Published: May 2007

Abstract: Oxidative stress is an important molecular mechanism for kidney injury in mercury poisoning. We studied lycopene, a potent carotenoid found in tomatoes due to its large antioxidant properties, and also evaluated the ability of lycopene to prevent HgCl2nephrotoxicity. Rats were injected with HgCl2(0 or 5 mg/kg body weight, subcutaneously) 6 hr after lycopene administration (0, 10, 25 or 50 mg/kg by gavage) and were killed 12 hr after HgCl2exposure. HgCl2‐induced inhibition of δ‐aminolevulinate dehydratase activity (∼35%) and increase of lipid peroxidation in kidney (∼37%) were prevented by lycopene. However, lycopene did not prevent the increase of plasma creatinine levels (∼123%) and renal tubular necrosis induced by HgCl2. Glutathione peroxidase and catalase activities were enhanced (∼71% and ∼41%), while superoxide dismutase activity was depressed (∼44%) in HgCl2‐treated rats when compared to control and these effects were prevented by lycopene. Our results indicate that although lycopene did not prevent HgCl2‐induced renal failure, it could play a beneficial role against HgCl2toxicity by preventing lipid peroxidation and changes in the activity of δ‐aminolevulinate dehydratase and antioxidant enzymes.
New-Onset Priapism Associated with Ingestion of Terazosin in an Otherwise Healthy Man
Authors: Sadeghi-Nejad Hossein , Jackson Imani
Published: May 2007

Introduction

Priapism has been reported as a rare effect of the commonly used alpha 1-antagonists through direct inhibition of the sympathetic input necessary for detumescence. Although previously reported as an adverse event in a patient with spinal cord injury, to the best of our knowledge, terazosin-induced priapism in an otherwise healthy man has not been previously described.

Aim

We describe an otherwise healthy man with lower urinary symptoms who developed priapism after ingestion of the commonly prescribed alpha-blocker terazosin.

Results

The priapism resolved after a combination of cavernosal aspiration and alpha-agonist administration.

Conclusion

Priapism is an extremely rare side effect of alpha-blocker therapy and has previously been described in association with other alpha-blockers, as well as with terazosin, in a spinal cord-injured patient. We report a case of priapism specifically associated with terazosin prescribed for lower urinary tract symptoms in an otherwise healthy man.
The Impact of Hunting on the Mammalian Fauna of Tropical Asian Forests
Authors: Corlett Richard T.
Published: May 2007

People have hunted mammals in tropical Asian forests for at least 40,000 yr. This period has seen one confirmed global extinction (the giant pangolin,Manis palaeojavanica) and range restrictions for several large mammals, but there is no strong evidence for unsustainable hunting pressure until the last 2000–3000 yr, when elephants, rhinoceroses, and several other species were progressively eliminated from the large parts of their ranges. Regional declines in most species have occurred largely within the last 50 yr. Recent subsistence hunting has typically focused on pigs and deer (hunted with dogs and spears or with snares), monkeys and other arboreal mammals (often caught with blowpipes), and porcupines and other rodents (smoked or dug out of burrows). Over the last 50 yr, the importance of hunting for subsistence has been increasingly outweighed by hunting for the market. The hunted biomass is dominated by the same species as before, sold mostly for local consumption, but numerous additional species are targeted for the colossal regional trade in wild animals and their parts for food, medicines, raw materials, and pets. Many populations of mammalian dispersers of large seeds and understory browsers have been depleted or eliminated, while seed predators have had a more variable fate. Most of this hunting is now illegal, but the law enforcement is generally weak. However, examples of successful enforcement show that hunting impacts can be greatly reduced where there is sufficient political will. Ending the trade in wild animals and their parts should have the highest regional conservation priority.
The Plight of Large Animals in Tropical Forests and the Consequences for Plant Regeneration
Authors: Wright S. Joseph , Stoner Kathryn E. , Beckman Noelle , Corlett Richard T. , Dirzo Rodolfo , Muller‐Landau Helene C. , Nuñez‐Iturri Gabriela , Peres Carlos A. , Wang Benjamin C.
Published: May 2007

We introduce a special section that addresses the bushmeat or wild meat crisis, its direct impact on game species, and its indirect impact on plants in tropical forests.
EMULSION CHARACTERISTICS OF BEEF AND SHEEP OFFAL
Authors: KURT ŞÜKRÜ , ZORBA ÖMER
Published: May 2007

Protein concentration, pH, emulsion capacity (EC), emulsion stability (ES), emulsion density (ED) and apparent yield stress of emulsion (raw emulsion; AYSe) and emulsion gel (cooked emulsion; AYSg) of sheep and beef offal (lung, liver, kidney, spleen and heart) were studied by using a model system.

The highest pH value was found in sheep kidney and the lowest pH value was found in sheep heart significantly (P < 0.01). The effect of species factor on the EC values of liver, kidney and spleen was found to be statistically insignificant. However, liver had the highest and heart had the lowest EC values significantly (P < 0.01). The highest ES and AYSg values were found in spleen, and these values were significantly (P < 0.01) higher in sheep spleen than in beef. The lowest AYSe value was found in kidney and the highest AYSe value was found in spleen. Significant differences were not found amoung the ED values of beef and sheep offal.
EFFECTS OF SHELF LIFE ENHANCERS AND MICROBIAL LOAD ON ESCHERICHIA COLI K12 SURVIVAL IN INJECTED BEEF STRIP STEAKS
Authors: PAULSON D.D. , WICKLUND R.A. , ROJAS M.C. , BREWER M.S.
Published: May 2007

The objective of this study was to determine whether sodium lactate (SL) or an SL/diacetate (SLDA) mixture added to an enhancement solution would effectively reduce microbial loads in surface‐inoculated, enhanced beef. Strip loins were cut into strip steaks (7.5 cm thick), then dipped into an inoculum containing either 103 or 106 cfu/mL Escherichia coli K12. Steaks were injected to a target of 110% over initial weight with one of three enhancement solutions to target final concentrations of: 0.3% salt + 0.3% phosphate (control), salt + phosphate + 0.3% SL or salt + phosphate + SL + 0.25% sodium diacetate. Steaks were vacuum packaged then held at 4C for up to 14 days. Plate counts, pH and color of steaks were determined after 0, 7 and 14 days. The SLDA mixture resulted in the greatest log reduction of coliforms in steaks. Both SL and SLDA resulted in darker steaks. The SL‐ and SLDA‐containing solutions also stabilized pH and decreased purge loss over time.
RELATIONSHIPS BETWEEN MICROSTRUCTURE AND MECHANICAL PROPERTIES OF CELLULAR CORNSTARCH EXTRUDATES
Authors: AGBISIT RODERICK , ALAVI SAJID , CHENG ENZHI , HERALD THOMAS , TRATER ALLEN
Published: May 2007

Relationships between mechanical properties and microstructure of brittle biopolymer foams were investigated using noninvasive imaging as a tool. Cornstarch was processed in a twin‐screw extruder to produce brittle foams with varying microstructure. X‐ray microtomography was used to measure microstructure features of the foams, including average cell diameter (2.07–6.32 mm), cell wall thickness (0.13–0.25 mm) and cell number density (18–146 cm
‐

3). Mechanical properties, including compression modulus (2.2–7.8 MPa), crushing stress (42–240 kPa), number of spatial ruptures (2.6–3.6 mm
‐

1), average crushing force (22–67 N) and crispness work (6.4–22 N·mm), were determined instrumentally. Compression modulus had a reasonably good fit (R2 = 0.72) with the Gibson–Ashby model for brittle foams, while crushing stress did not fit as well (R2 = 0.41). Cellular characteristics had moderate to high correlation (|r| = 0.48–0.81) with mechanical properties, and provided significant insight into the deformation mechanism of the foams.

PRACTICAL APPLICATIONS

Mechanical properties of extruded biopolymeric foams are largely determined by their microstructure, but the relationships involved have not been properly understood. This study used mechanical testing in combination withnoninvasive x‐ray microtomography to investigate these relationships. Results from this study furthered understanding of the deformation mechanism of brittle foams, and represent an important step toward the ability to better design crisp and crunchy food products with desired textures.
PROBABILISTIC CHARACTERISTICS OF STRESS CHANGES DURING CEREAL SNACK PUNCTURE
Authors: TSUKAKOSHI YOSHIKI , NAITO SHIGEHIRO , ISHIDA NOBUAKI
Published: May 2007

During puncture tests of Japanese cereal snacks, the force increases and decreases alternately. We herein compare the force–deformation curves recorded by two different testing machines and show that the number of changes in the curves depends on the testing machine. Thus, it is impossible to compare results obtained using different instruments. By removing the higher‐frequency components of the force–deformation curves, small events are easily missed. The number of large events decreases when lower‐frequency components are eliminated. This suggests the importance of providing the information on the frequency range of the testing machines. Nevertheless, the number of large force changes is similar between the examined machines. To model the size–frequency distribution, we selected a parametric probabilistic model from among the Weibull, exponential and Pareto distributions using Akaike information criterion and found that the Weibull or exponential distributions have a fit better than the Pareto distribution.

PRACTICAL APPLICATIONS

The methods developed in this work can be used to evaluate the quality of crisp snack food. By analyzing the samples obtained from a lot, samples with poor texture because of abnormal moisture levels and/or ingredients can be discerned and can be used to accept or reject the lot.
RHEOLOGICAL CHARACTERIZATION OF WET FOOD FOAMS
Authors: CHÁVEZ‐MONTES B. EDGAR , CHOPLIN LIONEL , SCHAER ERIC
Published: May 2007

Incorporating air bubbles into foods is a technical challenge, and in all cases, the fabrication of a foam goes through a “wet foam” stage, where bubbles are diluted in the food matrix and require stabilization. Sometimes, the end product is itself a wet foam, and a popular example is ice cream. This article describes a study of structural aspects of wet foams, where the continuous phase is a fluid, by means of dynamic rheological tests. The effects of formulation and processing conditions on aerated food foams are studied, and an example is presented for ice cream mix. The incorporation of gas bubbles at volume fractions of 50% or less modifies moderately the bulk rheological properties, and their effect can be predicted by the foam limit case. The continuous phase dominates to a great part the bulk's rheological behavior, and in the case of food systems, it stems from the presence of polysaccharide thickeners.

PRACTICAL APPLICATIONS

This work presents an alternative approach to study the rheological properties of short life and difficult‐to‐sample products, such as wet food foams, in a rheo‐reactor. Through the analysis of mechanical properties in oscillatory regime, the structure and stability of wet food foams can be characterized immediately after being fabricated in situ. This work presents new insights on the foaming step of ice cream mix (decoupled from the freezing step), and shows how the mechanical properties are affected by the incorporation ofbubbles, by process conditions and by the presence of thickeners and emulsifiers. This work can be a valuable guide to decide on optimal process and formulation to fabricate wet food foams (e.g., ice cream, aerated desserts) with specific mechanical properties and stability.
Effect of Calcium and Phosphorus, Residual Lactose, and Salt‐to‐Moisture Ratio on the Melting Characteristics and Hardness of Cheddar Cheese during Ripening
Authors: Chevanan N. , Muthukumarappan K.
Published: May 2007

ABSTRACT:  Meltability, melt profile parameters, and hardness of cheddar cheese prepared with varying levels of calcium (Ca) and phosphorus (P) content, residual lactose content, and salt‐to‐moisture ratio were studied at 0,1, 2, 4, 6, and 8 mo of ripening. Meltability, melt profile parameters, and hardness of cheddar cheeses measured at 0, 1, 2, 4, 6, and 8 mo of ripening showed significant interaction between the levels of Ca and P, residual lactose, salt‐to‐moisture ratio, and ripening time for most of the properties studied. cheddar cheese prepared with high Ca and P (0.67% Ca and 0.53% P) resulted in up to 6.2%, 4.5%, 9.6%, 5.0%, and 22.8% increase in softening time, softening temperature, melting time, melting temperature, and hardness, respectively, and 23.5%, 9.6%, and 3.2% decrease in meltability, flow rate, and extent of flow, respectively, compared to the cheddar cheese prepared with low Ca and P (0.53% Ca and 0.39% P). cheddar cheese prepared with high lactose (1.4%) content resulted in up to 7.7%, 7.0%, 4.9%, 4.2%, and 24.6% increase in softening time, softening temperature, melting time, melting temperature, and hardness, respectively, and 14.7%, 12.7%, and 2.8% decrease in meltability, flow rate, and extent of flow respectively compared to the cheddar cheese prepared with low lactose (0.78%) content. cheddar cheese prepared with high salt‐to‐moisture ratio (6.4%) resulted in up to 21.8%, 11.3%, 12.9%, 4.1%, and 29.4% increase in softening time, softening temperature, melting time, melting temperature, and hardness, respectively, and 13.2%, 28.6%, and 2.6% decrease in meltability, flow rate, and extent of flow, respectively, compared to the cheddar cheese prepared with low salt‐to‐moisture ratio (4.8%) during ripening.
Relationship of Land‐Use/Land‐Cover Patterns and Surface‐Water Quality in The Mullica River Basin1
Authors: Zampella Robert A. , Procopio Nicholas A. , Lathrop Richard G. , Dow Charles L.
Published: May 2007

Abstract:  We describe relationships between pH, specific conductance, calcium, magnesium, chloride, sulfate, nitrogen, and phosphorus and land‐use patterns in the Mullica River basin, a major New Jersey Pinelands watershed, and determine the thresholds at which significant changes in water quality occur. Nonpoint sources are the main contributors of pollutants to surface waters in the basin. Using multiple regression and water‐quality data for 25 stream sites, we determine the percentage of variation in the water‐quality data explained by urban land and upland agriculture and evaluate whether the proximity of these land uses influences water‐quality/land‐use relationships. We use a second, independently collected water‐quality dataset to validate the statistical models. The multiple‐regression results indicate that water‐quality degradation in the study area is associated with basin‐wide upland land uses, which are generally good predictors of water‐quality conditions, and that both urban land and upland agriculture must be included in models to more fully describe the relationship between watershed disturbance and water quality. Including the proximity of land uses did not improve the relationship between land use and water quality. Ten‐percent altered‐land cover in a basin represents the threshold at which a significant deviation from reference‐site water‐quality conditions occurs in the Mullica River basin.
Maximum likelihood estimation of proton irradiated field and deposited dose distribution
Authors: Inaniwa Taku , Kohno Toshiyuki , Yamagata Fumiko , Tomitani Takehiro , Sato Shinji , Kanazawa Mitsutaka , Kanai Tatsuaki , Urakabe Eriko
Published: May 2007

In proton therapy, it is important to evaluate the field irradiated with protons and the deposited dose distribution in a patient's body. Positron emitters generated through fragmentation reactions of target nuclei can be used for this purpose. By detecting the annihilation gamma rays from the positron emitters, the annihilation gamma ray distribution can be obtained which has information about the quantities essential to proton therapy. In this study, we performed irradiation experiments with mono‐energetic proton beams of and the spread‐out Bragg peak beams to three kinds of targets. The annihilation events were detected with a positron camera for after the irradiation and the annihilation gamma ray distributions were obtained. In order to evaluate the range and the position of distal and proximal edges of the SOBP, the maximum likelihood estimation (MLE) method was applied to the detected distributions. The evaluated values with the MLE method were compared with those estimated from the measured dose distributions. As a result, the ranges were determined with the difference between the MLE range and the experimental range less than for all targets. For the SOBP beams, the positions of distal edges were determined with the difference less than . On the other hand, the difference amounted to for proximal edges.
Dose calculation validation of VMC++ for photon beams
Authors: Gardner J. , Siebers J. , Kawrakow I.
Published: May 2007

The radiation therapy specific Voxel Monte Carlo (VMC++) dose calculation algorithm achieves a dramatic improvement in MC dose calculation efficiency for radiation therapy treatment planning dose evaluation compared with other MC algorithms. This work aims to validate VMC++ for radiation therapy photon beam planning. VMC++ was validated with respect to the well‐benchmarked EGS‐based DOSXYZnrc by comparing depth dose and lateral profiles for field sizes ranging from for 6 and beams in a homogeneous water phantom and in a simulated bone‐lung‐bone phantom. Patient treatment plan dose distributions were compared for five prostate plans and five head‐and‐neck (H/N) plans, all using intensity‐modulated radiotherapy beams. For all tests, the same incident particles were used in both codes to isolate differences due to modeling of the radiation source. Voxel‐by‐voxel observed differences were analyzed to distinguish between systematic and purely statistical differences. Dose‐volume‐histogram‐derived dose indices were compared for the patient plans. For the homogeneous water phantom and the bone‐lung‐bone phantom, the depth dose curve predicted by VMC++ agreed with that predicted by DOSXYZnrc within expected statistical uncertainty in all voxels except the surface voxel of the water phantom, where VMC++ predicted a lower dose. When the electron cutoff parameter was decreased for both codes, the surface voxel agreed within expected statistical uncertainty. For prostate plans, the most severe difference between the codes resulted in 55% of the voxels showing a systematic difference of 0.32% of maximum dose. For H/N plans, the largest difference observed resulted in 2% of the voxels showing a systematic difference of 0.98% of maximum dose. For the prostate plans, the most severe difference in the planning target volume was 0.4%, the rectum was 0.2%, the rectum was 0.2%, the bladder was 0.3% and the bladder was 0.3%. For the H/N plans, the most severe difference in the gross tumor volume was 0.4%, the clinical target volume was 0.2%, the nodes was 0.2%, the parotids was 0.8%, and the cord was 0.8%. All of these differences are clinically insignificant. VMC++ showed an average efficiency gain over DOSXYZnrc of at least an order of magnitude without introducing significant systematic bias. VMC++ can be used for photon beam MC patient dose computations without a clinically significant loss in accuracy.
An independent dose calculation algorithm for MLC‐based stereotactic radiotherapy
Authors: Lorenz Friedlieb , Killoran Joseph H. , Wenz Frederik , Zygmanski Piotr
Published: May 2007

We have developed an algorithm to calculate dose in a homogeneous phantom for radiotherapy fields defined by multi‐leaf collimator (MLC) for both static and dynamic MLC delivery. The algorithm was developed to supplement the dose algorithms of the commercial treatment planning systems (TPS). The motivation for this work is to provide an independent dose calculation primarily for quality assurance (QA) and secondarily for the development of static MLC field based inverse planning. The dose calculation utilizes a pencil‐beam kernel. However, an explicit analytical integration results in a closed form for rectangular‐shaped beamlets, defined by single leaf pairs. This approach reduces spatial integration to summation, and leads to a simple method of determination of model parameters. The total dose for any static or dynamic MLC field is obtained by summing over all individual rectangles from each segment which offers faster speed to calculate two‐dimensional dose distributions at any depth in the phantom. Standard beam data used in the commissioning of the TPS was used as input data for the algorithm. The calculated results were compared with the TPS and measurements for static and dynamic MLC. The agreement was very good for all tested cases except for very small static MLC sizes of and some ion chamber measurements in a high gradient region . This finding enables us to use the algorithm for routine QA as well as for research developments.
Nonparametric ROC and LROC analysis
Authors: Popescu Lucretiu M.
Published: May 2007

In this paper we review several results of the nonparametric receiver operating characteristic (ROC) analysis and present an extension to the nonparametric localization ROC (LROC) analysis. Equations for the estimation of the area under the characteristic curve and for the variance calculations are derived. Expressions for the choice of the optimal ratio between the number of signal‐absent and signal‐present image samples are also presented. The results can be applied both with continuous or discrete scoring scales. The simulation studies carried out validate the theoretical derivations and show that the LROC analysis is considerably more sensitive than the ROC analysis.
Adaptive deformable model for colonic polyp segmentation and measurement on CT colonography
Authors: Yao Jianhua , Summers Ronald M.
Published: May 2007

Polyp size is one important biomarker for the malignancy risk of a polyp. This paper presents an improved approach for colonic polyp segmentation and measurement on CT colonography images. The method is based on a combination of knowledge‐guided intensity adjustment, fuzzy clustering, and adaptive deformable model. Since polyps on haustral folds are the most difficult to be segmented, we propose a dual‐distance algorithm to first identify voxels on the folds, and then introduce a counter‐force to control the model evolution. We derive linear and volumetric measurements from the segmentation. The experiment was conducted on 395 patients with 83 polyps, of which 43 polyps were on haustral folds. The results were validated against manual measurement from the optical colonoscopy and the CT colonography. The paired ‐test showed no significant difference, and the correlation was 0.61 for the linear measurement and 0.98 for the volumetric measurement. The mean Dice coefficient for volume overlap between automatic and manual segmentation was 0.752 (standard deviation 0.154).
Influence of laser parameters on selective retinal treatment using single‐phase heat transfer analyses
Authors: Banerjee Rupak K. , Zhu Liang , Gopalakrishnan Pradeep , Kazmierczak Michael J.
Published: May 2007

Selective thermal treatment to retina is induced by short pulsed lasers to denaturize retinal pigment epithelium (RPE) selectively, while sparing the sensitive photoreceptors. The problem associated with the usage of short pulsed laser is the difficulty in determining the correct dosimetry parameters. This study quantifies the influence of laser parameters over the therapeutic range. The laser‐tissue interaction is numerically investigated by analyzing the transient temperature in ocular tissues during the treatment. The rate process analysis for thermal injury is employed to estimate the selective damage of retina. The contours of Arrhenius integral value presented in this study show both the area and magnitude of damage caused by various laser parameters. Results reveal that the pulsed laser with green wavelength and Gaussian profile is relatively more effective for selective retinal treatment. The repetition frequency of is found to produce selectively RPE damage, while higher frequencies produce collateral damage to neural retina and choroid located within from the RPE interface.
Water‐equivalent dosimeter array for small‐field external beam radiotherapy
Authors: Archambault Louis , Beddar A. Sam , Gingras Luc , Lacroix Fréderic , Roy René , Beaulieu Luc
Published: May 2007

With the increasing complexity of dose patterns external beam radiotherapy, there is a great need for new types of dosimeters. We studied the first prototype of a new dosimeter array consisting of water‐equivalent plastic scintillating fibers for dose measurement in external beam radiotherapy. We found that this array allows precise, rapid dose evaluation of small photon fields. Starting with a dosimeter system constructed with a single scintillating fiber coupled to a clear optical fiber and read using a charge coupled device camera, we looked at the dosimeter's spatial resolution under small radiation fields and angular dependence. Afterward, we analyzed the camera's light collection to determine the maximum array size that could be built. Finally, we developed a prototype made of ten scintillating fiber detectors to study the behavior and precision of this system in simple dosimetric situations. The scintillation detector showed no measurable angular dependence. Comparison of the scintillation detector and a small‐volume ion chamber showed agreement except for and fields where the output factor measured by the scintillator was higher. The actual field of view of the camera could accept more than 4000 scintillating fiber detectors simultaneously. Evaluation of the dose profile and depth dose curve using a prototype with ten scintillating fiber detectors showed precise, rapid dose evaluation even with placement of more than 75 optical fibers in the field to simulate what would happen in a larger array. We concluded that this scintillating fiber dosimeter array is a valuable tool for dose measurement in external beam radiotherapy. It possesses the qualities necessary to evaluate small and irregular fields with various incident angles such as those encountered in intensity‐modulated radiotherapy, radiosurgery, and tomotherapy.