bluuebunny/crossref_metadata_2025 huggingface dataset:
Ameloblastomas: a regional Latin‐American multicentric study
Authors: Ledesma‐Montes C , Mosqueda‐Taylor A , Carlos‐Bregni R , De León E Romero , Palma‐Guzmán JM , Páez‐Valencia C , Meneses‐García A
Published: January 2007

Aim:  To classify 163 ameloblastoma cases according to the new WHO Classification of Odontogenic Tumours (2005) and analyse their clinical and microscopic features.

Methods:  We studied the clinico‐pathological features of 163 ameloblastoma cases from nine regional Latin‐American institutions from Mexico and Guatemala.

Results:  Ameloblastomas comprised 22.7% of all odontogenic tumours. The mean age was 41.4 years for solid ameloblastoma (SA) and 26.3 years for unicystic ameloblastoma (UA) (P < 0.001) and both sexes were almost equally affected. The mandible was mainly affected for both UA and SA. The mean size was 6.2 cm for SA and 6.3 cm for UA cases. The recurrence rate was 21.7% for SA and 12.6% for UA. UA was twice as more frequent than the solid variant.

Conclusions:  In this study we found that UA was frequently misdiagnosed as SA; however, there are enough clinical and microscopic features that allow for an accurate differentiation between both types of ameloblastoma that should be recognized for surgical and prognostic purposes. In this study, SA was not found in patients younger than 20 years, UA had a constant myxoid stroma while mature connective tissue was more frequently associated with the solid type.
Expression of protease‐activated receptor‐1 and ‐2 in orofacial granulomatosis
Authors: Ketabchi S , Massi D , Ficarra G , Rubino I , Franchi A , Paglierani M , Simoni A , Capodiferro S , Favia G , Maiorano E , Tarantini F , Cirino G , Santucci M
Published: January 2007

Objective: Orofacial granulomatosis (OFG) is a rare condition characterized by non‐caseating granulomas in the orofacial region. Protease‐Activated Receptors (PARs) play a role in inflammatory diseases in diverse human tissues. The aim of the study was to investigate the expression of PAR‐1, PAR‐2, MMP‐2, MMP‐9, COX‐1, and COX‐2 in tissues taken from OFG patients.

Methods: PAR‐1, PAR‐2, MMP‐2, MMP‐9, COX‐1, and COX‐2 expression was evaluated by immunohistochemistry in biopsies taken from oral Crohn's disease (five cases), Melkersson–Rosenthal syndrome (MRS) (six cases), cheilitis granulomatosa (five cases) and normal oral mucosa (five cases).

Results: PAR‐1 was observed in mononuclear inflammatory cells in edematous/lichenoid lesions, whereas a strong PAR‐2 immunostaining was detected in epithelioid histiocytes and giant cells in granulomatous lesions, irrespective of the clinical features (CrohnvsMRS). MMPs and COX‐2 were expressed in the inflammatory component of edematous/lichenoid lesions and markedly overexpressed in granulomatous lesions. COX‐1 was weakly and variably expressed in both edematous/lichenoid and granulomatous lesions.

Conclusion: Thus, PAR‐1 and PAR‐2 expressions were related to the intensity and type of inflammatory response but not to the type of clinical lesion. Simultaneous overexpression of PARs, MMPs and COXs suggests synergism among these proinflammatory receptors and enzymes.
Functional characterization of artemin, a ferritin homolog synthesized in Artemia embryos during encystment and diapause
Authors: Chen Tao , Villeneuve Tania S. , Garant Katy A. , Amons Reinout , MacRae Thomas H.
Published: January 2007

Oviparously developing embryos of the crustacean Artemia franciscana encyst and enter diapause, exhibiting a level of stress tolerance seldom seen in metazoans. The extraordinary stress resistance of encysted Artemia embryos is thought to depend in part on the regulated synthesis of artemin, a ferritin superfamily member. The objective of this study was to better understand artemin function, and to this end the protein was synthesized in Escherichia coli and purified to apparent homogeneity. Purified artemin consisted of oligomers approximately 700 kDa in molecular mass that dissociated into monomers and a small number of dimers upon SDS/PAGE. Artemin inhibited heat‐induced aggregation of citrate synthase in vitro, an activity characteristic of molecular chaperones and shown here to be shared by apoferritin and ferritin. This is the first report that apoferritin/ferritin may protect cells from stress other than by iron sequestration. Stably transfected mammalian cells synthesizing artemin were more resistant to heat and H2O2 than were cells transfected with vector only, actions also shared by molecular chaperones such as the small heat shock proteins. The data indicate that artemin is a structurally modified ferritin arising either from a common ancestor gene or by duplication of the ferritin gene. Divergence, including acquisition of a C‐terminal peptide extension and ferroxidase center modification, eliminated iron sequestration, but chaperone activity was retained. Therefore, because artemin accumulates abundantly during development, it has the potential to protect embryos from stress during encystment and diapause without adversely affecting iron metabolism.
Inhibitory Effects of Artemisinin on Voltage‐Gated Ion Channels in Intact Nodose Ganglion Neurones of Adult Rats
Authors: Qiao Guofen , Li Shuo , Yang Baofeng , Li Baiyan
Published: January 2007

Abstract:   Recent data show that artemisinin has anti‐arrhythmic and local anaesthetic effects. To better understand the mechanisms, the effects of artemisinin on action potential discharge and voltage‐gated ion channels properties were studied on nodose ganglion neurones of adult rats with known sensory afferent fibre type using whole cell patch and vagus nodose slice preparation. The present data show that both depolarization and repolarization of action potentials were markedly inhibited by artemisinin in a concentration‐ and time‐dependent manner in either A‐type or C‐type nodose ganglion neurones without change in conduction velocity. Both tetrodotoxin‐sensitive (TTX‐S) Na+ and tetrodotoxin‐resistant (TTX‐R) Na+ currents were significantly reduced by micro‐perfusion of artemisinin; the steady‐state half‐activation and half‐inactivation for both TTX‐S and TTX‐R Na+ currents were shifted towards the right without changing slope factors. Median inhibition concentration (IC50) are 68.1 µM and 236.2 µM for TTX‐S and TTX‐R Na+ currents, respectively. Total outward K+ currents from C‐type nodose ganglion neurones were blocked by artemisinin 30–300 µM concentration‐dependently, IC50 being 104.7 µM. This effect was mimicked by tetraethylammonium 15 mM. Peak currents of N‐type Ca2+ channels were also reduced significantly (IC50=344.6 µM) in the presence of artemisinin, which was less effective than that induced by 1 µM ω‐conotoxin (CTX) GIVA. Our data demonstrate that depolarization and repolarization of action potentials recorded from either A‐ or C‐type nodose ganglion neurones were inhibited by artemisinin in a concentration‐ and time‐dependent manner, and that this inhibitory effect of artemisinin is probably due to the non‐selective inhibition of all major ion channels functionally expressed in nodose ganglion neurones.
Carnitine Deficiency Provokes Cisplatin‐Induced Hepatotoxicity in Rats
Authors: Al‐Majed Abdulhakeem A.
Published: January 2007

Abstract:  This study investigates whether or not carnitine deficiency is a risk factor and could contribute to cisplatin‐induced liver toxicity. A total of 60 adult male Wistar albino rats were divided into six groups. The first three groups were injected intraperitoneally with normal saline, propionyl‐l‐carnitine (500 mg/kg), and d‐carnitine (500 mg/kg), respectively, for 10 successive days. The fourth, fifth and sixth groups were injected intraperitoneally with the same doses of normal saline, propionyl‐l‐carnitine and d‐carnitine, respectively, for 5 successive days before and after a single dose of cisplatin (7 mg/kg). Administration of the standard nephrotoxic dose of cisplatin did not produce any changes in serum alanine transaminase and γ‐glutamyl transferase and no morphological changes in liver tissues. However, it did produce a significant increase in thiobarbituric acid reactive substances and total nitrate/nitrite and a significant decrease in reduced glutathione content in liver tissues. On the other hand, combined treatment with cisplatin and d‐carnitine induced a dramatic increase in serum alanine transaminase and γ‐glutamyl transferase, as well as progressive reduction in total carnitine and ATP content in liver tissue. Moreover, histopathological examination of liver tissues confirmed the biochemical data, where cisplatin and d‐carnitine combination showed signs of liver injury manifested as focal necro‐inflammatory changes and portal inflammation. Interestingly, in carnitine supplemented rats using propionyl‐l‐carnitine, cisplatin did not produce any biochemical and histopathological changes in liver tissues. In conclusion, data from this study suggest for the first time that (1) carnitine deficiency is a risk factor and could precipitate cisplatin‐induced hepatotoxicity, (2) oxidative stress is not the main cause of cisplatin‐related hepatotoxicity and (3) propionyl‐l‐carnitine prevents the development of cisplatin‐induced liver injury.
RELATIONS BETWEEN RHEOLOGICAL PROPERTIES, SALIVA‐INDUCED STRUCTURE BREAKDOWN AND SENSORY TEXTURE ATTRIBUTES OF CUSTARDS
Authors: JANSSEN ANKE M. , TERPSTRA MARJOLEIN E.J. , DE WIJK RENÉ A. , PRINZ JON F.
Published: January 2007

The relevance of initial rheological properties and mechanical and enzymatic structure breakdown in determining selected sensory texture attributes of custards was studied. The so‐called structure breakdown cell was used to characterize saliva‐induced breakdown, i.e., by monitoring digestion of starch by amylase from saliva. Based on rheological parameters, some attributes could be predicted well, while others more poorly or were not predicted. Predictable attributes were primarily determined by bulk properties; poorly and nonpredictable attributes originated from properties of the outer low‐viscosity surface layers or were not related to rheological properties. Both mechanical and enzymatic breakdown were important for creaminess, thickness and melting. Enzymatic breakdown was the dominant mechanism involved in the perception of fattiness, roughness and stickiness but not heterogeneity. Creaminess was the only attribute that was also determined by initial rheological properties and mechanical and enzymatic breakdown. Custards displaying high creaminess ratings had high initial stiffness, the structure broke down at low stress and enzymatic breakdown was slow. Microstructural organization of starch plays a dominating role in defining rheological and breakdown behavior of custards and in this way determines creaminess to a high extent.

PRACTICAL APPLICATIONS

Breakdown during eating is a complex process. In the work presented, breakdown of a semisolid food system is unravelled and linked to its microstructure and sensory perception. It is demonstrated that it is possible to reasonably predict sensory mouthfeel properties, especially the important attribute, creaminess, based on data from instrumental techniques. The knowledge obtained could be applied to high throughput screening of newly developed food products without the need of involving sensory panels. This will enable the food industry to increase the effectiveness and efficiency of the design and control of sensory attributes throughout the food product development process.
INFLUENCE OF XANTHAN GUM AND TAPIOCA STARCH ON THE RETROGRADATION AND GELATION OF FINGER MILLET (ELEUSINE CORACANA L. GAERTNER) STARCH PASTES
Authors: OJIJO NELSON K.O. , SHIMONI EYAL
Published: January 2007

Dynamic storage modulus, G′, was used to monitor the primary retrogradation tendency of model paste systems involving finger millet starch (FMS)–tapioca and FMS–xanthan gum mixtures during cooling and curing for 48 h at 25C. Xanthan gum enhanced retrogradation during cooling and did not reduce retrogradation in cured pastes relative to control finger millet pastes. FMS–tapioca mixtures exhibited reduced retrogradation during cooling and curing. Mechanical spectra of FMS–tapioca pastes indicated extensive paste network development in hot pastes and proper gels in cooled and cured pastes. Zero shear viscosity values of FMS–tapioca mixtures at some ratios indicated enhanced viscosity over and above the sum effect of the individual component starches at the same concentration. Reduced retrogradation and network development in FMS–tapioca mixtures was attributed to some kind of a “functional energy.” These results demonstrate the applicability of starch mixtures to improve functionality and confer physical stability in food products.

PRACTICAL APPLICATIONS

Finger millet is a potential source of commercial native starch. Finger millet starch exhibits functional synergism with tapioca. Mixtures of the two starches can be simple and cost‐effective means for thickening food systems such as meat products, soups, and gravies, and abating retrogradation effects in gruels.
EFFECT OF MOISTURE AND WATER ACTIVITY ON TEXTURAL PROPERTIES OF RAW AND ROASTED COFFEE BEANS
Authors: PITTIA PAOLA , NICOLI MARIA CRISTINA , SACCHETTI GIAMPIERO
Published: January 2007

The effect of moisture and water activity (Aw) on the textural properties of raw and roasted (light, medium and dark) coffee beans was investigated. Water–coffee interactions were described by the sorption isotherm and the mechanical properties of the samples equilibrated in the 0–0.95 Aw range were studied by uniaxial compression were studied. Roasted beans presented a lower strength and toughness than raw ones and, independently from roasting, resulting textural properties were highly dependent on Aw. At increasing hydration degree, an increase in strength and toughness was observed until a critical Aw value, different for raw (0.75) and roasted (ca. 0.86) beans related to a water, was reached. This was plasticization effect. Above these critical Aw values, a progressive softening of the bean matrix occurs. In roasted coffee beans, this plasticization determined the loss of the characteristic brittleness. The critical Aw value, above which plasticization occurred, was determined by modeling the compressive modulus using the Fermi's distribution function.

PRACTICAL APPLICATIONS

Coffee beans are a highly hygroscopic matrix and could readily take up moisture when exposed to the environment during storage. The characteristic brittleness and fragility induced by roasting is the primary attribute of roasted coffee beans. It is of great interest for process purposes to limit the textural changes of beans during their shelf‐life, mainly in relation to the grinding step carried out on roasted coffee beans before the extraction of coffee brew. The investigation of the effect of water content and state on textural properties of both raw and roasted coffee beans could have implications regarding the work to be applied during the grinding process.
Stroke and Thrombolysis in Developing Countries
Authors: Pandian Jeyaraj Durai , Padma Vasantha , Vijaya Pamidimukkala , Sylaja P. N. , Murthy Jagaralpudi M. K.
Published: January 2007

Background Over the past few decades, the burden of stroke in developing countries has grown to epidemic proportions. Two-thirds of global stroke occurs in low- and middle-income countries. We have found that little information is obtainable concerning the availability of thrombolysis therapy in developing countries.

Summary of review

The epidemiology of stroke is well investigated in the developed world; however, in the developing world stroke is less well documented. Most of the available stroke data from these countries are hospital-based. Stroke thrombolysis is currently used in few developing countries like Brazil, Argentina, Senegal, Iran, Pakistan, China, Thailand, and India. The two main barriers for implementation of thrombolysis therapy in developing countries are the high cost of tissue plasminogen activator and lack of proper infrastructure. Most of the centers with the infrastructure to deliver thrombolysis for stroke are predominantly private sector, and only available in urban areas.

Conclusion

Until a more cost-effective thrombolytic agent and the proper infrastructure for widespread use of thrombolysis therapy are available, developing nations should focus on primary and secondary stroke prevention strategies and the establishment of stroke units wherever possible. Such multi-faceted approaches will be more cost-effective for developing countries than the use of thrombolysis.
Relationship between stimulation train characteristics and dynamic human skeletal muscle performance
Authors: Maladen R. , Perumal R. , Wexler A. S. , Binder‐Macleod S. A.
Published: January 2007

Aim:  The purpose of the present study was to investigate the effect of activation frequency on dynamic human muscle performance for a range of train durations and number of pulses during free limb movement.

Methods:  The quadriceps femoris muscles of 10 subjects were activated with stimulation trains with different activation frequency, train durations and number of pulses. The peak excursion produced in response to each train was the dependent measure of muscle performance.

Results:  The excursion–frequency (for a 300‐ms train duration) and excursion–train duration (for trains with frequencies of 10, 30 or 59 Hz) relationships could each be fit with a two‐parameter exponential equation (R2 values > 0.97). Because the number of pulses in a stimulation train is a function of both train duration and frequency, the excursion produced as a function of the number of pulses was characterized by a three‐parameter exponential equation that represented this combined relationship. The relationship between the measured and predicted excursions in response to a wide range of stimulation trains had a R2 = 0.96. In addition, one‐way repeated measures analyses of variance (anovas) showed that the frequency at which the maximum excursion was produced increased with an increase in the number of pulses in the trains tested.

Conclusion:  These results show the importance of train duration and the number of pulses contained within a train on the relationship between activation frequency and human skeletal muscle performance.
Passive mechanical properties and structure of the aorta: segmental analysis
Authors: Sokolis D. P.
Published: January 2007

Aim:  This study assessed segmental changes in the mechanical properties of the aorta at low, physiologic and high stresses, in relation with wall composition and morphometry.

Methods:  The aorta of 10 healthy pigs was divided into six thoracic and three abdominal segments. Aortic specimens were mechanically tested to failure, i.e. rupture, using a uniaxial tension device. Elastic modulus–stress curves were obtained for low (part I), physiologic (part II) and high (part III) stresses, and submitted to regression analysis; failure parameters were calculated. Histological evaluation was performed using an image‐processing system, with quantification of morphometric parameters and composition of the entire vessel and its layers, i.e. media and adventitia.

Results:  Significant differences were found in the regression parameters of parts I, II and III, and in failure parameters, suggesting that the proximal segments were stiffer at low stresses, whereas the distal were less extensible, stronger and stiffer at physiologic and high stresses. Image analysis demonstrated significant differences in morphometry and composition among the different layers and segments of the aorta, with higher elastin content proximally and collagen content distally. Good correlations were found between the regression parameters of parts I and II and elastin content, and between the failure and regression parameters of parts II and III and collagen content.

Conclusion:  Segmental changes exist in the structure and mechanical properties of the aorta, depending on the level of aortic pressure. This information is necessary for understanding aortic function at general non‐physiologic stress states.
Upregulation of the brain renin–angiotensin system in rats with chronic renal failure
Authors: Nishimura M. , Takahashi H. , Yoshimura M.
Published: January 2007

Aim:  We investigated how the brain renin–angiotensin system is involved in regulation of the sympathetic activity and arterial pressure in rats with chronic renal failure.

Methods:  Systolic arterial pressure, heart rate and diurnal urinary noradrenaline excretion were measured for 12 weeks in spontaneously hypertensive rats (SHR) with or without subtotal nephrectomy. Expression of mRNAs related to the brain renin–angiotensin system was measured using polymerase chain reaction. Effects of a 6‐day intracerebroventricular infusion of a type 1 angiotensin II receptor antagonist (candesartan) or bilateral dorsal rhizotomy on these variables were also investigated.

Results:  Systolic arterial pressure and urinary excretion of noradrenaline were consistently higher in subtotally nephrectomized SHR than in sham‐operated SHR (262 ± 5 vs. 220 ± 3 mmHg, P < 0.001; 2.71 ± 0.22 vs. 1.69 ±0.19 ng g−1 body weight day−1, P < 0.001). Expression of renin, angiotensin‐converting enzyme and type 1 angiotensin II receptor mRNAs in the hypothalamus and lower brainstem was greater in subtotally nephrectomized SHR than in sham‐operated SHR. Continuous intracerebroventricular infusion of candesartan attenuated hypertension and the increase in urinary noradrenaline excretion in subtotally nephrectomized SHR. Dorsal rhizotomy decreased arterial pressure, urinary excretion of noradrenaline and expression of renin–angiotensin system‐related mRNAs in brains of subtotally nephrectomized SHR.

Conclusion:  The brain renin–angiotensin system in subtotally nephrectomized SHR appears to be activated via afferent nerves from the remnant kidney, resulting in sympathetic overactivity and hypertension in this chronic renal failure model.
In Defense of the Hopkins Lead Abatement Studies
Authors: Ross Lainie Friedman
Published: January 2007

In August 2001, the Maryland Court of Appeals harshly criticized the Kennedy Krieger Institute of Johns Hopkins University for knowingly exposing poor children to lead-based paint. The court’s decision made national news, and is worth examining because it raises several very important issues for research ethics.

The research conducted by the Institute was an attempt to understand how successful different lead abatement programs were in reducing continued lead exposure to children. Previously, Julian Chisolm and Mark Farfel, of John Hopkins University, had disclosed the dangers of traditional dust-generating deleading practices. In the current study, Dr. Farfel and colleagues sought to document the longevity of various lead-based paint abatement strategies.
I Need a Placebo like I Need a Hole in the Head
Authors: Weijer Charles
Published: January 2007

In this issue of the Journal of Law, Medicine & Ethics Peter Clark provides a comprehensive and sound ethical analysis of clinical trials examining the treatment of advanced Parkinson's disease with fetal tissue transplantation. These studies raise profound questions about how clinical trials of surgical interventions ought to be conducted. At stake is not only the ethical basis of such trials, but differing views as to the proper role of science in medicine and its limitations.

Experience with the broader debate on the ethical permissibility of placebo controls has taught us that the choice of control treatment is an aspect of trial design in which ethical and scientific issues overlap. Accordingly, I will highlight, and perhaps expand upon, three issues raised by Clark: What scientific questions ought clinical trials of surgical interventions ask? How should the ethical analysis of risk for such trials be conceived? And, are surgical patients a vulnerable population?
The Physician as Gatekeeper to the Use of Genetic Information in the Criminal Justice System
Authors: Seiden Samuel C. , Morin Karine ,   for the Council on Ethical and Judicial Affairs, American Medical Association
Published: January 2007

The discovery of the molecular structure of deoxyribonucleic acid (DNA) and the science of molecular biology have profoundly changed medicine’s diagnostic capability and promise to transform the therapeutic realm. When some genetic disorders are diagnosed, physicians can intervene for prevention or treatment. While the basic structure of DNA is the same for all human beings, no two individuals, other than identical twins (or cloned individuals), have the same DNA sequence. This discovery has had important repercussions in the criminal justice system, where DNA can serve as an identification tool.

At the crossroads of these different uses of DNA, there are great concerns about potential misuses of genetic information. Preventing disease, curing illness, and convicting criminals are all seen as worthwhile uses of the technology, but concerns of potential misuse in medicine or in the criminal justice system are not unfounded. A 1998 American Medical Association (AMA) study showed that 68 percent of patients had fears that their genetic test results would be used against them by their employers or insurers. Others, pointing to racial profiling, have suggested that we may now face genetic profiling.
The Dalai Lamas and State Power1
Authors: Maher Derek F.
Published: January 2007

This article explores the evolving political standing of members of the Dalai Lama incarnation lineage. I survey the history of Tibet since the time of Tsong kha pa, the original inspiration for the dGe lugs School, showing how each Dalai Lama established his own position with an ever evolving set of external circumstances framed by rival schools, patrons, Mongolian khans, Chinese emperors, the nobility, the powerful monasteries, and their own regents. I conclude that there is no single model that captures the nature of the relationship between the Dalai Lamas and state power.
What's New in the History of Christianity?
Authors: Thayer Anne
Published: January 2007

Current scholarship shows a growing commitment to study churches outside the West and to allow their histories to shape the way the overall narratives are told. New research, employing a range of methodologies, focuses on minority religious traditions and the complexities of lived religion.
Effect of Extraction Conditions on the Yield and Purity of Apple Pomace Pectin Precipitated but Not Washed by Alcohol
Authors: Garna Haikel , Mabon Nicolas , Robert Christelle , Cornet Charlotte , Nott Katherine , Legros Hervé , Wathelet Bernard , Paquot Michel
Published: January 2007

ABSTRACT:  A study of the influence of extraction conditions (pH: 1.5 to 2; temperature: 80 to 90 °C; extraction time: 1 to 3 h), on the yield and purity of apple pomace pectin without elimination of impurities by alcohol washing was carried out. The alcohol precipitate yields varied from 2.9% to 8.9% depending on the pH. At pH 1.5, these yields were higher than those obtained at pH 2 contrary to the galacturonic acid purity (%w/w). Compounds other than pectins were solubilized from the cell walls of apple pomace at pH 1.5, and they were precipitated with alcohol. The apple pectins obtained from the different extraction procedures were highly methylated (54.5% to 79.5%), especially when the conditions (temperature, pH) were drastic. Similar conclusions can be drawn for the neutral sugar content that decreased at pH 1.5 (arabinose, xylose, and galactose) or at the highest temperatures and extraction times (arabinose and galactose). The phenomenon of demethylation and pectin degradation of neutral sugars chains can be observed at acid pH, and for long extraction times. The presence of high quantities of mannose or fructose, glucose, and xylose in the alcohol precipitate showed that pectin precipitation with ethanol was not specific.
How Does Cooking Time Scale with Size? A Numerical Modeling Approach
Authors: Lee S. H. , Datta A. K. , Rao M. A.
Published: January 2007

ABSTRACT:  A mathematical model for a spatially distributed mechanical property such as Young's modulus and texture inside solid food during the cooking process was developed by combining a numerical conduction heat transfer model with the kinetics of property changes. Using the distributed mechanical property obtained from the thermokinetic model, linear elastic stress analysis was performed to determine the effective material property and how it changes during cooking. Spatial variation in the mechanical property is found to be significant for commonly used food sizes in potato. When property varies spatially, volume average property, which is easier to compute than an effective property obtained from mechanical stress analysis, can be a substitute for the effective property. Cooking time based on volume average Young's modulus varies less strongly with size than how temperature varies with size. When activation energy for the property change kinetics is lower, cooking time varies less with size. The scaling of cooking time with size and kinetics and the extent of property variation in a sample during cooking should provide useful guidelines in automating cooking processes.
Effect of Molecular Weight, Type of Chitosan, and Chitosan Solution pH on the Shelf‐Life and Quality of Coated Eggs
Authors: Kim Su Hyun , No Hong Kyoon , Prinyawiwatkul Witoon
Published: January 2007

ABSTRACT:  Effects of the molecular weight and type of chitosans and pH of chitosan solution on antibacterial activity against Salmonella enterica Enteritidis and on internal quality of chitosan‐coated eggs were evaluated during 4 wk of storage at 25 °C. Two types of chitosans were studied: α‐chitosans with 4 different molecular weights (Mw = 282, 440, 746, and 1110 kDa) and β‐chitosan (Mw = 577 kDa). The α‐chitosan with 282 kDa exhibited stronger bactericidal effects than did other α‐ and β‐chitosans. The weight loss, Haugh unit, and yolk index values suggested that coating of eggs with α‐chitosan with 282 kDa increased the shelf‐life of eggs by almost 3 wk at 25 °C compared with noncoated eggs. The pH (4.5, 5.0, and 5.5) of the α‐chitosan (282 kDa) solution did not affect the internal quality of chitosan‐coated eggs. Therefore, coating of eggs with 282 kDa α‐chitosan without pH adjustment (initial pH of 4.5) may offer a protective barrier against contamination of S. Enteritidis while simultaneously preserving the internal quality of eggs.
Evaluation of Solubilized Proteins as an Alternative to Phosphates for Meat Enhancement
Authors: Vann Dustin G. , Mireles DeWitt Christina A.
Published: January 2007

ABSTRACT:  Select grade strip loins (n= 10) were enhanced 10% with either a phosphate or an acid solubilized protein solution. Color score, aerobic plate count, lipid oxidation, purge loss, cook yield, Warner–Bratzler shear force, and sensory analysis were measured to characterize storage quality. The phosphate injection consisted of 4.5% phosphate, 3.6% sodium chloride, 90.9% water, and 1% Herbalox seasoning. Two solutions were prepared for the protein injection: one consisting of 1:9 protein to water and the other an aqueous solution of 1% Herbalox seasoning and 3.6% sodium chloride. Enhancement solutions were injected twice at 5% to create a 10% total injection. It was found that the protein‐enhanced steaks were comparable to phosphate‐enhanced steaks for percent discoloration and overall acceptability. The phosphate‐enhanced steaks performed better than the protein‐enhanced steaks for lean color, fat color, aerobic plate count, lipid oxidation, percent purge, cook yield, and Warner–Bratzler shear force. It should be noted that for protein‐enhanced steaks, lean color and cook yield, although statistically different, did perform similar to phosphate‐enhanced steaks.
Computational Approaches to Investigate How Biological Macromolecules Can Be Protected in Extreme Conditions
Authors: Dashnau J.L. , Vanderkooi J.M.
Published: January 2007

ABSTRACT:  Water is required to hydrate molecules, but under cold conditions water freezes and under dehydrating conditions water evaporates—thus presenting a dilemma for organisms that live in extreme environments. Organisms have developed various strategies for protection against extreme temperatures and dehydration. In this review, we describe how the interaction of water and 2 natural cryoprotectants, namely glycerol and sugars, can be studied at the molecular level. Techniques using infrared spectroscopy and computation are described. In the case of glycerol, H‐bonding of water to the OH groups of glycerol limits the amount of water available to form ice and prevents crystallization at low temperatures. For aldohexopyranose sugars, the different isomeric forms have different water H‐bonding networks, which are consistent with isomeric‐dependent activities. By studying the strategies used in nature, derivatives for use in food preservation can be more readily developed.
Sex-Specific UV and Fluorescence Signals in Jumping Spiders
Authors: Lim Matthew L. M. , Land Michael F. , Li Daiqin
Published: January 2007

No animals are known to possess both ultraviolet (UV) reflectance and fluorescence that are sex-specific. We provide evidence for this separation in the jumping spider Cosmophasis umbratica, which has UV reflectance and UV-induced green fluorescence restricted to males and females, respectively. During courtship, many of the studied pairs failed to show typical display posturing when UV light was blocked. Occluding the UV component of sunlight to only one of each pair also caused atypical behavior: Females showed no interest in non‐UV-reflective courting males, and males either ignored or were lackluster in courting nonfluorescing females. These results demonstrate the importance of both sex-specific hues as sexual signals for effective intraspecific communication.
Kinetics of Morphogen Gradient Formation
Authors: Kicheva Anna , Pantazis Periklis , Bollenbach Tobias , Kalaidzidis Yannis , Bittig Thomas , Jülicher Frank , González-Gaitán Marcos
Published: January 2007

In the developing fly wing, secreted morphogens such as Decapentaplegic (Dpp) and Wingless (Wg) form gradients of concentration providing positional information. Dpp forms a longer-range gradient than Wg. To understand how the range is controlled, we measured the four key kinetic parameters governing morphogen spreading: the production rate, the effective diffusion coefficient, the degradation rate, and the immobile fraction. The four parameters had different values for Dpp versus Wg. In addition, Dynamin-dependent endocytosis was required for spreading of Dpp, but not Wg. Thus, the cellular mechanisms of Dpp and Wingless spreading are different: Dpp spreading requires endocytic, intracellular trafficking.
A Plasminogen-Activating Protease Specifically Controls the Development of Primary Pneumonic Plague
Authors: Lathem Wyndham W. , Price Paul A. , Miller Virginia L. , Goldman William E.
Published: January 2007

Primary pneumonic plague is transmitted easily, progresses rapidly, and causes high mortality, but the mechanisms by which
Yersinia pestis
overwhelms the lungs are largely unknown. We show that the plasminogen activator Pla is essential for
Y. pestis
to cause primary pneumonic plague but is less important for dissemination during pneumonic plague than during bubonic plague. Experiments manipulating its temporal expression showed that Pla allows
Y. pestis
to replicate rapidly in the airways, causing a lethal fulminant pneumonia; if unexpressed, inflammation is aborted, and lung repair is activated. Inhibition of Pla expression prolonged the survival of animals with the disease, offering a therapeutic option to extend the period during which antibiotics are effective.
Arguing for Atheism
Authors: Shermer Michael
Published: January 2007

The God Delusion
.
By Richard Dawkins
. Bantam, London, 2006. 416 pp. £20. ISBN 9780593055489. Houghton Mifflin, Boston, 2006. $27, C$35.95. ISBN 9780618680009.

The author argues that we would gain much if we relegated religious beliefs to our history.
Development of Novel Real-Time PCR Assays for Detection and Differentiation of Eleven Medically Important
Aspergillus
and
Candida
Species in Clinical Specimens
Authors: Schabereiter-Gurtner Claudia , Selitsch Brigitte , Rotter Manfred L. , Hirschl Alexander M. , Willinger Birgit
Published: January 2007

In the present study, novel real-time PCR assays targeting the fungal ITS2 region were developed for the detection and differentiation of medically important
Aspergillus
species (
Aspergillus fumigatus
,
Aspergillus flavus
,
Aspergillus nidulans
,
Aspergillus niger
, and
Aspergillus terreus
) and
Candida
species (
Candida albicans
,
Candida dubliniensis
,
Candida glabrata
,
Candida krusei
,
Candida parapsilosis
, and
Candida tropicalis
) using a LightCycler instrument. The combination of a group-specific and a universal primer with five
Aspergillus
or six
Candida
species-specific biprobes in one reaction mixture facilitated rapid screening and species differentiation by the characteristic peak melting temperatures of the biprobes. Both assays can be performed either as single assays or simultaneously in the same LightCycler run. The analytical sensitivity using pure cultures and EDTA-anticoagulated blood, cerebrospinal fluid (CSF), and tissue samples spiked with
A. fumigatus
and
C. albicans
cell suspensions was shown to be at least 1 CFU per PCR, corresponding to 5 to 10 CFU/ml blood and 10 CFU/200 μl CSF or 0.02 g tissue. To assess the clinical applicability, 26 respiratory samples, 4 tissue samples from the maxillary sinus, and 1 blood sample were retrospectively tested and real-time PCR results were compared with results from culture, histology, or a galactomannan enzyme-linked immunosorbent assay (ELISA). Twenty samples (64.5%) were both culture positive and positive by real-time PCR. Six samples (19.4%) showed no growth of fungi but were positive by real-time PCR. However, all of the tissue samples were positive by both PCR and histology. The blood sample showed no growth of
Aspergillus
, but aspergillosis was confirmed by positive galactomannan ELISA, histology, and PCR results. The remaining samples (16.1%) were culture and PCR negative; also, no other signs indicating fungal infection were observed. Our data suggest that the
Aspergillus
and
Candida
assays may be appropriate for use in clinical laboratories as simple and rapid screening tests for the most frequently encountered
Aspergillus
and
Candida
species and might become an important tool in the early diagnosis of fungal infections in the future.
Use of Dried Spots of Whole Blood, Plasma, and Mother's Milk Collected on Filter Paper for Measurement of Human Immunodeficiency Virus Type 1 Burden
Authors: Ayele Workenesh , Schuurman Rob , Messele Tsehaynesh , Dorigo-Zetsma Wendelien , Mengistu Yohannes , Goudsmit Jaap , Paxton William A. , de Baar Michel P. , Pollakis Georgios
Published: January 2007

We studied the use of dried spots of bodily fluids (plasma, whole blood, and mother's milk) on filter paper as a means of sample collection and storage for human immunodeficiency virus type 1 (HIV-1) viral load testing under stringent field conditions. Plasma placed directly in lysis buffer, which is customarily used for viral load assays, was used for comparison in all our experiments. Utilizing reconstruction experiments, we demonstrate no statistical differences between viral loads determined for plasma and mother's milk spotted on filter paper and those for the same fluids placed directly in lysis buffer. We found that the addition of whole blood directly to lysis buffer was unreliable and could not be considered a feasible option. However, viral load measurements for whole blood spotted onto filter paper correlated with plasma viral load values for both filter spots and lysis buffer (Pearson correlation coefficients, 0.7706 and 0.8155, respectively). In conclusion, dried spots of plasma, whole blood, or mother's milk provide a feasible means for the collection, storage, and shipment of samples for subsequent viral load measurement and monitoring. Virus material spotted and dried on filter paper is a good inexpensive alternative for collecting patient material to monitor the HIV-1 viral load. Measuring the HIV-1 burden from whole blood dried on filter paper provides a suitable alternative for low-technology settings with limited access to refrigeration, as can be found in sub-Saharan Africa.
Improvement of Hepatitis C Virus (HCV) Genotype Determination with the New Version of the INNO-LiPA HCV Assay
Authors: Bouchardeau Françoise , Cantaloube Jean François , Chevaliez Stéphane , Portal Christine , Razer Annie , Lefrère Jean-Jacques , Pawlotsky Jean Michel , De Micco Philippe , Laperche Syria
Published: January 2007

Hepatitis C virus (HCV) isolates have been classified into six main genotypes. Genotyping methods, and especially the widely used line probe assay (LiPA), are frequently based on the 5′-untranslated region (5′UTR). However, this region is not appropriate for discriminating HCV strains at the subtype level and for distinguishing many genotype 6 samples from genotype 1. We investigated the capacity of a novel LiPA (Versant HCV Genotype 2.0 assay) based on the simultaneous detection of 5′UTR and Core regions for genotypes 1 and 6 to provide correct HCV genotypes (characterized with a phylogenetic analysis) in a set of HCV strains mainly encountered in Western countries. The improvement was assessed by comparing the results to those obtained with the previous version of the assay. Of the 135 tested samples, 64.7% were concordant for genotype group and subtype with sequencing reference results using the Versant HCV Genotype 2.0 assay versus 37.5% with the previous version. The yield was mainly related to a better characterization of genotype 1, since the accuracy, tested in 62 genotype 1 samples, increased from 45.2% with the first version to 96.8% with the new one. However, this new version necessitates a specific PCR and could no longer be used after 5′UTR PCR used for current HCV infection diagnosis. Moreover, the information provided by 5′UTR hybridization is not reliable for correctly identifying the diversity within genotypes 2 and 4. Thus, the Versant HCV Genotype 2.0 assay remains a useful tool for clinical practice when only the discrimination between major HCV genotypes is necessary.
Kodamaea ohmeri
Isolates from Patients in a University Hospital: Identification, Antifungal Susceptibility, and Pulsed-Field Gel Electrophoresis Analysis
Authors: Lee Jin Sol , Shin Jong Hee , Kim Mi-Na , Jung Sook-In , Park Kyung Hwa , Cho Duck , Kee Seung Jung , Shin Myung Geun , Suh Soon Pal , Ryang Dong Wook
Published: January 2007

Data on clinical isolates of
Kodamaea
(
Pichia
)
ohmeri
, an emerging fungal pathogen, are scarce. Over the past 5 years, we identified yeast isolates from nine patients with fungemia as
K. ohmeri
by using the API 20C system. Here, we reanalyzed these isolates first by sequencing the internal transcribed spacer 2 (ITS2) regions and then by growing the isolates on CHROMagar
Candida
medium and subjecting them to pulsed-field gel electrophoresis (PFGE). Based on their ITS2 sequences, six of the nine isolates were confirmed as
K. ohmeri
, while the others were identified as
Candida haemulonii
(
n
= 2) and
Candida parapsilosis
(
n
= 1). PFGE karyotyping of the
K. ohmeri
isolates revealed similar major bands, and their colonies showed a characteristic color change from pink to blue when grown on CHROMagar
Candida
medium for more than 48 h. For
K. ohmeri
, the ranges of MICs of fluconazole, voriconazole, caspofungin, and micafungin were 2 to 32 μg/ml, 0.03 to 0.5 μg/ml, 0.125 to 0.25 μg/ml, and 0.03 to 0.06 μg/ml, respectively. Restriction endonuclease analysis of genomic NotI-digested DNA (REAG-N) from isolates from different patients produced unique patterns, suggesting that the fungemia had occurred sporadically. This study determined that ITS2 sequence data, PFGE karyotypes, and CHROMagar
Candida
chromogenic culture medium are reliable diagnostic tools for identifying
K. ohmeri
while REAG-N is useful for genotyping the clinical isolates of
K. ohmeri
.
Frequent Intrapatient Recombination between Human Immunodeficiency Virus Type 1 R5 and X4 Envelopes: Implications for Coreceptor Switch
Authors: Mild Mattias , Esbjörnsson Joakim , Fenyö Eva Maria , Medstrand Patrik
Published: January 2007

Emergence of human immunodeficiency virus type 1 (HIV-1) populations that switch or broaden coreceptor usage from CCR5 to CXCR4 is intimately coupled to CD4
+
cell depletion and disease progression toward AIDS. To better understand the molecular mechanisms involved in the coreceptor switch, we determined the nucleotide sequences of 253 V1 to V3
env
clones from 27 sequential HIV-1 subtype B isolates from four patients with virus populations that switch coreceptor usage. Coreceptor usage of clones from dualtropic R5X4 isolates was characterized experimentally. Sequence analysis revealed that 9% of the clones from CXCR4-using isolates had originated by recombination events between R5 and X4 viruses. The majority (73%) of the recombinants used CXCR4. Furthermore, coreceptor usage of the recombinants was determined by a small region of the envelope, including V3. This is the first report demonstrating that intrapatient recombination between viruses with distinct coreceptor usage occurs frequently. It has been proposed that X4 viruses are more easily suppressed by the immune system than R5 viruses. We hypothesize that recombination between circulating R5 viruses and X4 viruses can result in chimeric viruses with the potential to both evade the immune system and infect CXCR4-expressing cells. The broadening in cell tropism of the viral population to include CXCR4-expressing cells would gradually impair the immune system and eventually allow the X4 population to expand. In conclusion, intrapatient recombination between viruses with distinct coreceptor usage may contribute to the emergence of X4 viruses in later stages of infection.
Modest Human Immunodeficiency Virus Coreceptor Function of CXCR3 Is Strongly Enhanced by Mimicking the CXCR4 Ligand Binding Pocket in the CXCR3 Receptor
Authors: Hatse Sigrid , Huskens Dana , Princen Katrien , Vermeire Kurt , Bridger Gary J. , De Clercq Erik , Rosenkilde Mette M. , Schwartz Thue W. , Schols Dominique
Published: January 2007

The chemokine receptor CXCR3 can exhibit weak coreceptor function for several human immunodeficiency virus type 1 (HIV-1) and HIV-2 strains and clinical isolates. These viruses produced microscopically visible cytopathicity in U87.CD4.CXCR3 cell cultures, whereas untransfected (CXCR3-negative) U87.CD4 cells remained uninfected. Depending on the particular virus, the coreceptor efficiency of CXCR3 was 100- to >10,000-fold lower compared to that of CXCR4. A CXCR3 variant carrying the CXCR4 binding pocket was constructed by simultaneous lysine-to-alanine and serine-to-glutamate substitutions at positions 300 and 304 of the CXCR3 receptor. This mutant receptor (CXCR3[K300A, S304E]) showed markedly enhanced HIV coreceptor function compared to the wild-type receptor (CXCR3[WT]). Moreover, the CXCR4 antagonist AMD3100 exhibited antagonistic and anti-HIV activities in U87.CD4.CXCR3[K300A, S304E] cells but not in U87.CD4.CXCR3[WT] cells.