Pectin Conformation in Solution.

The interplay of degree of methylesterification (DM), pH, temperature, and concentration on the macromolecular interactions of pectin in solution has been explored. Small-angle X-ray scattering complemented by atomic force microscopy and molecular dynamics was employed to probe chain dimensions and solution structure. Two length scales have been observed with the first level of structure characterising chain clusters with sizes ranging between 100-200 nm. The second level of structure arises from single biopolymer chains with a radius of gyration between ∼6 and 42 nm. The development of a range of macromolecular dimensions in vitro and in silico shows that the chain flexibility increases with DM and at acidic pH, whereas hydrogen bonding is the responsible thermodynamic driving force for cluster formation. High methyl pectins create structures of lower fractal dimension with less efficient packing. This work unveils pectin conformations covering most of its industrially and biologically relevant environments, enabling rational design of advanced biomaterials based on pectin.

Understanding surface reactivity of Si electrodes in Li-ion batteries by in operando scanning electrochemical microscopy.

In operando SECM is employed to monitor the evolution of the electrically insulating character of a Si electrode surface during (de-)lithiation. The solid-electrolyte interface (SEI) formed on Si electrodes is shown to be intrinsically electrically insulating. However, volume changes upon (de-)lithiation lead to the loss of the protecting character of the initially formed SEI.

Structural modifications of the salivary conditioning film upon exposure to sodium bicarbonate: implications for oral lubrication and mouthfeel.

The salivary conditioning film (SCF) that forms on all surfaces in the mouth plays a key role in lubricating the oral cavity. As this film acts as an interface between tongue, enamel and oral mucosa, it is likely that any perturbations to its structure could potentially lead to a change in mouthfeel perception. This is often experienced after exposure to oral hygiene products. For example, consumers that use dentifrice that contain a high concentration of sodium bicarbonate (SB) often report a clean mouth feel after use; an attribute that is clearly desirable for oral hygiene products. However, the mechanisms by which SB interacts with the SCF to alter lubrication in the mouth is unknown. Therefore, saliva and the SCF was exposed to high ionic strength and alkaline solutions to elucidate whether the interactions observed were a direct result of SB, its high alkalinity or its ionic strength. Characteristics including bulk viscosity of saliva and the viscoelasticity of the interfacial salivary films that form at both the air/saliva and hydroxyapatite/saliva interfaces were tested. It was hypothesised that SB interacts with the SCF in two ways. Firstly, the ionic strength of SB shields electrostatic charges of salivary proteins, thus preventing protein crosslinking within the film and secondly; the alkaline pH (≈8.3) of SB reduces the gel-like structure of mucins present in the pellicle by disrupting disulphide bridging of the mucins via the ionization of their cysteine's thiol group, which has an isoelectric point of ≈8.3.

Promising results after the treatment of simple and complex distal humerus type C fractures by angular-stable double-plate osteosynthesis.

INTRODUCTION: The aim of this study was to evaluate the functional results and complications following open reduction and internal fixation of distal humerus type C fractures (AO classification) using an anatomically precontoured, angular-stable double-plate system. PATIENTS AND METHODS: The study is a retrospective analysis of 45 patients with 46 type C fractures. There was one C1, eight C2 and 31 C3 fractures. Twelve fractures were open (Gustilo classification). Follow-up was performed on 38 patients with 39 fractures (84%) after 14 months (range, 12-22). The mean age was 50 years (range, 14-87). Functional results were evaluated using the Mayo Elbow Performance Score (MEPS); the Disabilities of the Arm, Shoulder and Hand score (DASH); and range-of motion (ROM) measurements. Complications were classified as minor or major, and the postoperative and follow-up X-rays were analyzed. RESULTS: Thirty-four fractures were considered stable to allow early physical therapy. With a mean MEPS of 85 points, 36 results (36/39 [92%]) were rated as excellent or good. The mean DASH was 22.5 points, and the ROM for extension-flexion was 105° (range, 50-145). Sixteen major complications (eventually coexistent: 6 × implant failure, 3 × non-union, 6 × stiffness, 2 × necrosis capitulum, 4 × failure olecranon osteotomy refixation) and two minor complications were recorded in 17 patients. These adverse events led to 14 revision surgeries (14/39 [36%]). Except for extension deficit, no statistically significant differences were found between the articular simple and articular complex fractures and when comparing the results between patients with and without a major complication. CONCLUSION: The anatomically precontoured and angular-stable double-plate system provides sufficient immediate postoperative stability to allow early physiotherapy, even in C3-type fractures. Excellent or good results could be achieved in the vast majority of patients, independent on having suffered a complication or not. Complication rates were remarkably high, emphasizing the difficulties associated with this rare type of fracture. LEVEL OF EVIDENCE: Level IV Retrospective study.

Effect of calcium ions on in vitro pellicle formation from parotid and whole saliva.

The salivary pellicle is a protein-rich, bacteria-free, self-assembling film that adsorbs to all surfaces within the oral cavity. The pellicle has numerous functions that are vital for maintaining oral health. Currently however, there are no commercially available artificial salivas that accurately mimic the complex film forming properties (i.e. film thickness and viscoelasticity) of human saliva. To understand these properties further we have examined the in vitro formation of the salivary pellicle, by adsorbing stimulated parotid saliva (PS) and whole mouth saliva (WMS) from 14 healthy volunteers, onto oxidised silicon surfaces, using a quartz crystal microbalance with dissipation monitoring (QCMD) and a dual polarisation interferometer (DPI). A dramatic impact on the hydrated mass, polymer mass, thickness and polymer concentration of the pellicle for both WMS and PS was observed when the natural calcium concentration of the respective salivas was increased from 0 mM to 10mM. In addition, QCMD data showed that on addition of 10mM calcium the salivary pellicle formed by both PS and WMS became more predominantly elastic. The results presented here also suggest that calcium can easily diffuse in and out of the pellicle, permitting free calcium exchange between the saliva and the adsorbed pellicle under physiological conditions, which may potentially facilitate the mineralisation of enamel.

Results of screening for intracranial aneurysms in patients with coarctation of the aorta.

BACKGROUND AND PURPOSE: IAs are found in 2.3% of adults; the mean age at detection is 52 years. Prevalence is <0.5% in young adults. Early studies suggest that 10%-50% of patients with aortic coarctation have IAs. Screening recommendations are variable. We sought to examine the prevalence of IAs through screening with MRA. MATERIALS AND METHODS: Consecutive patients older than 16 years of age with coarctation undergoing brain MRA between May 1999 and October 2007 were included. MRA was performed by using a 1.5T scanner with a 3D time-of-flight protocol; simultaneous MR imaging was performed of the heart and aorta. Cerebral MRAs were double-reported by a neuroradiologist. Statistics are described as mean ± SD and median ± range. Continuous variables were compared by using Student t tests and Mann-Whitney U tests (categoric variables, by using the Fisher exact test). RESULTS: One hundred seventeen MRAs were double-reported. The median age was 29 ± 11 years (range, 16-59 years). IAs were found in 12 patients (10.3%). The mean diameter of IAs was 3.9 mm (range, 2.0-8.0 mm). Patients with aneurysms were older (median, 37 years; range, 16-50 years) than those without (median, 23 years; range, 16-59 years; Z = -2.01, P = .04). Hypertension was more common in those with IAs (IA 83% versus no IA 43%, P = .01). There was no association between ascending aortopathy, bicuspid aortic valves, and IAs. CONCLUSIONS: Patients with coarctation have a higher prevalence of IAs, occurring at an earlier age than in population studies. Whether routine screening is appropriate for this group of patients is unclear. Hypertension is likely to be an important pathophysiologic factor.

One-third tubular-hook-plate osteosynthesis for olecranon osteotomies in distal humerus type-C fractures: a preliminary report of results and complications.

INTRODUCTION: Distal humerus fractures are rare and challenging to treat. Anatomic reduction of the articular surface and stable osteosynthesis are mandatory for satisfactory results. The transolecranon approach allows superior visualisation of the joint. However, controversy exists regarding how best to fix the osteotomy. The purpose of the present study was to investigate the eligibility of a one-third tubular hook plate for osteosynthesis of olecranon osteotomies in distal humerus type-C fractures. PATIENTS AND METHODS: A consecutive series of 34 patients who were treated through an olecranon osteotomy and underwent fixation using a one-third tubular hook plate were identified. Thirty-one patients (17 females, 14 males) with a median age of 50 years (14-87, standard deviation (SD) 18.3) were available for a comprehensive assessment after a mean of 12.3 months (6-20, SD 3.7). Using the Arbeitsgemeinschaft für Osteosynthesefragen (AO) classification, six (19.4%) fractures were categorised as type C2 and 25 (80.6%) were categorised as C3. Physical and radiological examinations were performed. The Mayo Elbow Performance Score (MEPS) and the Disabilities of the Arm, Shoulder and Hand score (DASH) were evaluated. RESULTS: Mean extension-flexion ROM was found to be 102° (50-145°, SD 25). Pronation and supination were only slightly compromised. The mean MEPS was 87.2 points (50-100, SD 12.4). Fourteen patients (45.2%) were rated as excellent, and 15 (48.4%) were rated as good. One patient was rated fair, and one patient was rated as poor, respectively. Mean DASH score was 24.4 points (0-65, SD 20.3). Complications regarding the osteotomy occurred in seven patients (22.5%). Revision surgery was necessary in five cases (16%). At follow-up, all osteotomies went on to union. Mild joint degeneration (Broberg I) was found in 10 patients (32.2%). Implant removal was carried out in 15 patients (48.4%). CONCLUSION: Based on this study, the osteosynthesis of olecranon osteotomies using a one-third tubular hook plate can be regarded as a safe procedure with a low complication rate. The implant needed is widely available and cost-efficient, in contrast to specially designed plates or nails.

Interfacial & colloidal aspects of lipid digestion.

Amongst the main issues challenging the food manufacturing sector, health and nutrition are becoming increasingly important. Global concerns such as obesity, the ageing population and food security will have to be addressed. Food security is not just about assuring food supply, but is also about optimising nutritional delivery from the food that is available [1]. Therefore one challenge is to optimise the health benefits from the lipids and lipid soluble nutrients. Colloid scientists have an affinity for lipids because they are water insoluble, however this presents a challenge to the digestive system, which has to convert them to structures that are less insoluble so they are available for uptake. Despite this, the human digestive system is remarkably effective at digesting and absorbing most lipids. This is primarily driven through maximising energy intake, as lipids possess the highest calorific value, which was a survival trait to survive times of famine, but is now an underlying cause of obesity in developed countries with high food availability. The critical region here is the lipid-water interface, where the key reactions take place to solubilise lipids and lipid soluble nutrients. Digestive lipases have to adsorb to the oil water interface in order to hydrolyse triacylglycerols into fatty acids and mono glycerides, which accumulate at the interface [2], and inhibit lipase activity. Pancreatic lipase, which is responsible for the majority of lipid hydrolysis, also requires the action of bile salts and colipase to function effectively. Bile salts both aid the adsorption of co-lipase and lipase, and help solubilise the lipolysis products which have accumulated at the interface, into mixed micelles composing bile salts and a range of other lipids, to facilitate transport to the gut mucosal surface prior to uptake and absorption. The process can be affected by the lipid type, as shorter chain, fatty acids are more easily absorbed, whereas the uptake of longer chain fatty acids, particularly the very long chain n-3 fatty acids from fish oils are dependent on source and so may depend on food microstructure for optimal uptake [3]. The uptake of some poorly water soluble nutrients are enhanced by the presence of lipids, but the mechanisms are not clear. In addition, controlling the digestion of lipids can be beneficial as slower release of lipids into the bloodstream can reduce risk of cardiovascular disease, and can promote gut feedback processes that reduce appetite. This presents an opportunity to colloid and interfacial science, as there are many unanswered questions regarding the specific physicochemical mechanisms underlying the process of lipid digestion and uptake. I will review our current knowledge of lipid digestion and present examples of how fundamental research in colloidal and interface science is beginning to address these issues. These include the adsorption behaviour of physiological surfactants such as bile salts; interfacial processes by which different polar lipids can influence lipolysis; and the effect of emulsion based delivery systems on cellular uptake of lipid soluble nutrients. A fundamental understanding of these processes is required if we are to develop intelligent design strategies for foods that will deliver optimal nutrition and improved health benefits in order to address the global challenges facing the food sector in the future.

Stability of Evolving Multiagent Systems.

A multiagent system is a distributed system where the agents or nodes perform complex functions that cannot be written down in analytic form. Multiagent systems are highly connected, and the information they contain is mostly stored in the connections. When agents update their state, they take into account the state of the other agents, and they have access to those states via the connections. There is also external user-generated input into the multiagent system. As so much information is stored in the connections, agents are often memory less. This memory-less property, together with the randomness of the external input, has allowed us to model multiagent systems using Markov chains. In this paper, we look at multiagent systems that evolve, i.e., the number of agents varies according to the fitness of the individual agents. We extend our Markov chain model and define stability. This is the start of a methodology to control multiagent systems. We then build upon this to construct an entropy-based definition for the degree of instability (entropy of the limit probabilities), which we used to perform a stability analysis. We then investigated the stability of evolving agent populations through simulation and show that the results are consistent with the original definition of stability in nonevolving multiagent systems, proposed by Chli and De Wilde. This paper forms the theoretical basis for the construction of digital business ecosystems, and applications have been reported elsewhere.

[Prehospital airway management of laryngeal tubes. Should the laryngeal tube S with gastric drain tube be preferred in emergency medicine?]. / Präklinische Anwendung des Larynxtubus. Bietet der Larynxtubus S mit Magensonde Vorteile in der Notfallmedizin?

Laryngeal tubes (LT) are increasingly being used for emergency airway management. This article reports on two patients in whom out-of-hospital intubation with a single-lumen LT was associated with massive pulmonary aspiration in one patient and gastric overinflation in the other. In both cases peak inspiratory pressures exceeded the LT leak pressure of approximately 35 mbar. This resulted in gastric inflation and decreased pulmonary compliance and increased inspiratory pressure further, thereby creating a vicious circle. It is therefore recommended that laryngeal tube suction (LTS) should be used in all cases of emergency airway management and a gastric drain tube be inserted through the dedicated second lumen. Apart from gastric overinflation, incorrect LT/LTS placement must be detected and immediately corrected, e.g. in cases of difficult or impossible gastric tube placement, permanent drainage of air from the gastric tube, decreasing minute ventilation or an ascending capnography curve.

[Functional results after osteosynthesis of the distal humerus fracture with an anatomically precontoured, angular-stable double plate system]. / Funktionelle Ergebnisse nach winkelstabiler Osteosynthese der distalen Humerusfraktur mit einem anatomisch präformierten Doppelplattensystem.

AIM: The aim of this study was to evaluate the functional results and determine/record the complications after treating distal humerus fractures with an anatomically precontoured and angular-stable double plate system (LCP Distal Humerus Plates, Synthes GmbH, Umkirch). METHOD: 51 patients (30 female, 21 male) with 52 fractures of the distal humerus and a mean age of 51 years (14-94) were prospectively recorded over a period of 42 months and treated by open reduction and internal fixation using the above-mentioned LCP Distal Humerus Plates System. Follow-up was performed in 44 patients with 45 fractures after a mean of 13 months (6-24). According to the classification system introduced by the "Arbeitsgemeinschaft für Osteosynthesefragen" (AO [Association for the study of internal fixation, ASIF]) there were six A fractures (13.3%), five B fractures (11.1%) and 34 C fractures (75.5%). The AO/ASIF rate of type C3 fractures was 53%. Seven fractures were grade I (15.6 %) and three fractures grade II (6.7%) open. In addition to clinical examination and measuring range of motion (ROM), functional results were evaluated using the Mayo elbow performance score (MEPS) and the disabilities of the arm, shoulder and hand score (DASH). RESULTS: Using the MEPS, excellent results were achieved in 19 patients (43.2%), good in 23 (52.3%), fair and poor each in one. Mean MEPS was 87.5 +/- 11.8 points (50-100). The mean DASH score reached 14.2 +/- 19.9 (0-65.8). Having a mean extension deficit of 10 +/- 14.1 degrees (0-40 degrees) and flexion up to 127.5 +/- 17.2 degrees (80-145 degrees), the mean ROM was 110 +/- 23.8 degrees (50-145 degrees). A primary stable osteosynthesis which allows early physiotherapy was gained in 38 fractures, in seven cases additional immobilisation was carried out (10 to 28 days). Postoperative complications were seen in eleven patients (24.4%). Overall revision surgery was necessary in nine cases. CONCLUSION: By using the anatomically precontoured and angular-stable LCP distal humerus plates system a stable osteosynthesis allowing early physiotherapy is achieved in the majority of patients. Due to early initiation of physical therapy the functional results might be improved. Despite using the LCP system complications at the distal humerus fracture side were seen frequently, emphasising the challenging surgical procedure and demonstrating the need for further implant and surgical procedure improvement.

Assessment of preoperative ultrasonography of the neck and elective neck dissection in patients with oral squamous cell carcinoma.

Estimating the value of our preoperative workup in the treatment of patients with clinically N0 (cN0) squamous cell carcinoma of the oral cavity. Retrospective analysis. Results of preoperative palpation, ultrasound (US) and ultrasound-guided fine needle aspiration cytology (FNAC) were compared to the histological findings after unilateral or bilateral elective selective neck dissection of level I-III (SND I-III) in patients with cN0 squamous cell carcinoma of the oral cavity. Occult metastases were detected by in 50 (22%) out of the 224 cN0 patients. No metastases were found beyond level III in extended neck dissections. T1N0M0 tumors and T2N0M0 tumors metastasized in 8 out of 77 cases (10%) and 32 out of 112 (29%) cases, respectively. Staging of the cN0 neck by palpation and US (+/-ultrasound-guided FNAC) missed occult lymph node metastases in 22% of the patients with oral cavity squamous cell carcinoma. The use of SND I-III therefore still is warranted. Frozen section sampling seemed to be redundant in this selected group of patients, because no additional metastases were found in extended neck dissection specimens. It might not be necessary to perform elective neck dissection in patients with T1 tumors.

Molecular marker assisted broadening of the Central European heterotic groups in rye with Eastern European germplasm.

Broadening the genetic base of heterotic pools is a key to ensure continued genetic gains in hybrid breeding and extend hybrid cultivation to new areas. In the present study, two Central European heterotic pools (Carsten and Petkus) and five Eastern European open-pollinated varieties (OPVs, Pop-1 to Pop-5) were studied with the objectives to (1) investigate the genetic diversity in OPVs and the heterotic pools using molecular and field data, (2) evaluate the molecular diversity among OPVs, (3) examine the combining ability for grain yield of the OPVs when crossed with testers in field trials, and (4) develop a strategy for targeted introgression of OPV germplasm into the heterotic pools. In total, 610 S(0) plants, 347 from OPVs and 263 from heterotic pools, were developed. Clones of the S(0) plants of OPVs were crossed with two testers belonging to each heterotic pool, while clones of heterotic pools were crossed with only the opposite tester. Testcrosses were evaluated for grain yield in multi-location trials. In addition, 589 S(0) plants were fingerprinted with 30 SSR markers. The data revealed that the Carsten pool has a narrow genetic base and should be the primary target for broadening the established heterotic pattern. Mean and genetic variance suggested that Pop-2 and Pop-4 are good candidates for introgression in Petkus pool and Pop-5 in Carsten pool. Nevertheless, introgression of Pop-5 in Carsten could reduce the genetic diversity between heterotic pools. Therefore, we suggest that either selected plants of Pop-5 should be introgressed or more Eastern European germplasm should be fingerprinted and field evaluated to identify promising germplasm for broadening the established heterotic pattern.

Comparison of the orogenic displacement of sodium caseinate with the caseins from the air-water interface by nonionic surfactants.

Displacement of sodium caseinate from the air-water interface by nonionic surfactants Tween 20 and Tween 60 was observed by atomic force microscopy (AFM). The interfacial structure was sampled by Langmuir-Blodgett deposition onto freshly cleaved mica substrates. Protein displacement occurred through an orogenic mechanism: it involved the nucleation and growth of surfactant domains within the protein network, followed by failure of the protein network. The surface pressure at which failure of the protein network occurred was essentially independent of the type of surfactant. The major component of sodium caseinate is beta-casein, and previous studies at the air-water interface have shown that beta-casein networks are weak, failing at surface pressures below that observed for sodium caseinate. The other components of sodium caseinate are alpha(s)- and kappa-caseins. Studies of the displacement of alpha(s)-caseins from air-water interfaces show that these proteins also form weak networks that fail at surface pressures below that observed for sodium caseinate. However, kappa-casein was found to form strong networks that resisted displacement and failed at surface pressures comparable to those observed for sodium caseinate. The AFM images of the displacement suggest that, despite kappa-casein being a minor component, it dominates the failure of sodium caseinate networks: alpha(s)-casein and beta-casein are preferentially desorbed at lower surface pressures, allowing the residual kappa-casein to control the breakdown of the sodium caseinate network at higher surface pressures.

The effect of physiological conditions on the surface structure of proteins: setting the scene for human digestion of emulsions.

Understanding and manipulating the interfacial mechanisms that control human digestion of food emulsions is a crucial step towards improved control of dietary intake. This article reports initial studies on the effects of the physiological conditions within the stomach on the properties of the film formed by the milk protein (ß-lactoglobulin) at the air-water interface. Atomic force microscopy (AFM), surface tension and surface rheology techniques were used to visualize and examine the effect of gastric conditions on the network structure. The effects of changes in temperature, pH and ionic strength on a preformed interfacial structure were characterized in order to simulate the actual digestion process. Changes in ionic strength had little effect on the surface properties. In isolation, acidification reduced both the dilatational and the surface shear modulus, mainly due to strong repulsive electrostatic interactions within the surface layer and raising the temperature to body temperature accelerated the rearrangements within the surface layer, resulting in a decrease of the dilatational response and an increase of surface pressure. Together pH and temperature display an unexpected synergism, independent of the ionic strength. Thus, exposure of a pre-formed interfacial ß-lactoglobulin film to simulated gastric conditions reduced the surface dilatational modulus and surface shear moduli. This is attributed to a weakening of the surface network in which the surface rearrangements of the protein prior to exposure to gastric conditions might play a crucial role.

The prediction of mandibular invasion by squamous cell carcinomas with the expression of osteoclast-related cytokines in biopsy specimens.

Destruction of bone by tumour is caused by osteoclasts rather than by tumour cells directly. Tumour cells of invasive oral squamous cell carcinomas (SCC) release osteoclast-related cytokines and cytokines activate osteoclasts. The purpose of this study was to investigate the possibility of predicting mandibular invasion by SCC by analysis of the expression of osteoclast-related cytokines in biopsy specimens of SCC, adjacent or fixed to the mandible. Thirty-five biopsy specimens from the pathology archives were examined from patients who had been treated for SCC, adjacent or fixed to the mandible. The patients were divided into those with and without medullary invasion. The expression of tumour necrosis factor (TNF)-alpha, interleukin (IL)-6 and IL-11 was studied by immunohistochemical analysis. No significant differences were found in expression of TNF-alpha, IL-6 and IL-11 between biopsy specimens with or without medullary invasion. Quantification of the density of tumour-infiltrating lymphocytes was not reproducible. In conclusion, the expression of TNF-alpha, IL-6 and IL-11 in biopsy specimens of SCC, adjacent or fixed to the mandible, is not an appropriate method for predicting the presence of medullary invasion of the mandible.

Testcross performance of rye introgression lines developed by marker-assisted backcrossing using an Iranian accession as donor.

Introgression libraries facilitate the identification of favorable exotic alleles or genomic regions, which can be exploited for improving elite breeding material. We evaluated the first two introgression libraries in rye (Secale cereale L.) on the phenotypic and molecular level. Our objectives were to detect candidate introgression lines (pre-ILs) with a better testcross performance than the recurrent parent and identify donor chromosome segments (DCS) responsible for the improved performance. We introduced DCS from the self-incompatible heterozygous exotic Iranian primitive rye accession Altevogt 14160 (donor) into the genetic background of the elite inbred line L2053-N (recurrent parent) by marker-assisted backcrossing and developed 40 BC(2)S(3) lines in each introgression library. Testcross performance for three agronomic and six quality traits was evaluated in replicated field trials across two testers at five locations over 2 years. The phenotypic effect of the DCS was analyzed for all traits. The pre-ILs had on average a testcross performance comparable to that of the recurrent parent. Significant (P < 0.05) differences between individual pre-ILs and the recurrent parent were detected for all traits except for heading date. For more than 60% of the significant (P < 0.05) differences, the pre-ILs were superior to the recurrent parent. For some pre-ILs, specific DCS were identified containing presumably quantitative trait loci responsible for the superior hybrid performance. Consequently, our study revealed that the development and employment of introgression libraries offers the opportunity for a targeted increase of genetic diversity of elite rye material for hybrid performance of agronomically important traits.

No high-risk HPV detected in SCC of the oral tongue in the absolute absence of tobacco and alcohol--a case study of seven patients.

INTRODUCTION: In recent years, there has been an increase in the number of patients with squamous cell carcinoma (SCC) of the mobile tongue in the absence of tobacco and alcohol. The literature suggests that human papilloma virus (HPV) may be involved in the development of SCC of the head and neck, especially in non-smoking and non-drinking patients. In the oral cavity, however, the presence of the HPV genome has been reported with various percentages. This may be due to misclassification of the oropharyngeal tongue as oral cavity subsite and the use of various detection methods. MATERIALS AND METHODS: Therefore, we evaluated the role of HPV in seven consecutive non-smoking and non-drinking patients (2003-2006) with a SCC located at the oral, mobile tongue using in situ hybridization and SPF(10)Line Blot 25 polymerase chain reaction assays. RESULTS: No HPV was detected in these specimens. To further determine whether a relationship exists between HPV and SCC in the absence of tobacco and alcohol, subsequent studies at specific locations are necessary.

Effect of hydrocarbon chain and pH on structural and topographical characteristics of phospholipid monolayers.

Structural characteristics (structure, elasticity, topography, and film thickness) of dipalmitoyl phosphatidylcholine (DPPC) and dioleoyl phosphatidylcholine (DOPC) monolayers were determined at the air-water interface at 20 degrees C and pH values of 5, 7, and 9 by means of surface pressure (pi)-area (A) isotherms combined with Brewster angle microscopy (BAM) and atomic force microscopy (AFM). From the pi-A isotherms and the monolayer elasticity, we deduced that, during compression, DPPC monolayers present a structural polymorphism at the air-water interface, with the homogeneous liquid-expanded (LE) structure; the liquid-condensed structure (LC) showing film anisotropy and DPPC domains with heterogeneous structures; and, finally, a homogeneous structure when the close-packed film molecules were in the solid (S) structure at higher surface pressures. However, DOPC monolayers had a liquid-expanded (LE) structure under all experimental conditions, a consequence of weak molecular interactions because of the double bond of the hydrocarbon chain. DPPC and DOPC monolayer structures are practically the same at pH values of 5 and 7, but a more expanded structure in the monolayer with a lower elasticity was observed at pH 9. BAM and AFM images corroborate, at the microscopic and nanoscopic levels, respectively, the same structural polymorphism deduced from the pi-A isotherm for DPPC and the homogeneous structure for DOPC monolayers as a function of surface pressure and the aqueous-phase pH. The results also corroborate that the structural characteristics and topography of phospholipids (DPPC and DOPC) are highly dependent on the presence of a double bond in the hydrocarbon chain.

Establishment of introgression libraries in hybrid rye (Secale cereale L.) from an Iranian primitive accession as a new tool for rye breeding and genomics.

Genetic diversity of elite breeding material can be increased by introgression of exotic germplasm to ensure long-term selection response. The objective of our study was to develop and characterize the first two rye introgression libraries generated by marker-assisted backcrossing and demonstrate their potential application for improving the baking quality of rye. Starting from a cross between inbred line L2053-N (recurrent parent) and a heterozygous Iranian primitive population Altevogt 14160 (donor) two backcross (BC) and three selfing generations were performed to establish introgression libraries A and B. Amplified fragment length polymorphisms (AFLP markers) and simple sequences repeats (SSRs) were employed to select and characterize candidate introgression lines (pre-ILs) from BC(1) to BC2S3. The two introgression libraries comprise each 40 BC2S3 pre-ILs. For analyzing the phenotypic effects of the exotic donor chromosome segment (DCS) we evaluated the per se performance for pentosan and starch content in replicated field trials at each of four locations in 2005 and 2006. Introgression library A and B cover 74 and 59% of the total donor genome, respectively. The pre-ILs contained mostly two to four homozygous DCS, with a mean length of 12.9 cM (A) and 10.0 cM (B). We detected eight (A) and nine (B) pre-ILs with a significant (P<0.05) higher pentosan content and two pre-ILs (B) with a significant (P<0.05) higher starch content than the elite recurrent parent. Thus, our results indicate that exotic genetic resources in rye carry favorable alleles for baking quality traits, which can be exploited for improving the elite breeding material by marker-assisted selection (MAS). These introgression libraries can substantially foster rye breeding programs and provide a promising opportunity to proceed towards functional genomics.