bluuebunny/crossref_metadata_2025 huggingface dataset:
Roles of interstitial cells of Cajal in regulating gastrointestinal motility: in vitro versus in vivo studies
Authors: Yin Jieyun , Chen Jiande D.Z.
Published: April 2008

Subtypes and functions of ICC in the gut

Mutant animal models used in in vitro and in vivo studies

Roles of ICC in generating slow waves

Roles of ICC in regulating gastrointestinal motility

Roles of ICC in mediating neural transmission

Roles of ICC as mechanoreceptors

Conclusions

The aim of this article is to provide a better understanding of the roles of interstitial cells of Cajal (ICC) in regulating gastrointestinal motility by reviewing in vitro and in vivo physiological motility studies. Based on the in vitro studies, ICC are proposed to have the following functions: to generate slow waves, to mediate neurotransmission between the enteric nerves and the gastrointestinal muscles and to act as mechanoreceptors. However, there is limited evidence available for these hypotheses from the in vivo motility studies. In this review, we first introduce the major subtypes of ICC and their established functions. Three Kit mutant mouse and rodent models are presented and the loss of ICC subtypes in these mutants is reviewed. The physiological motility findings from various in vitroand in vivo experiments are discussed to give a critical review on the roles of ICC in generating slow waves, regulating gastrointestinal motility, mediating neural transmission and serving as mechanoreceptors. It is concluded that the role of ICC as pacemakers may be well established, but other cells may also be involved in the generation of slow waves; the theory that ICC are mediators of neurotransmission is challenged by the majority of the in vivo motility studies; the hypothesis that ICC are mechanoreceptors has not found supportive evidence from the in vivo studies yet. More studies are needed to explain discrepancies in motility findings between the in vitro and in vivo experiments.
Evaluation on the movement of endosseous titanium implants under continuous orthodontic forces: an experimental study in the dog
Authors: Hsieh Yao‐Dung , Su Ching‐Ming , Yang Yi‐Hsin , Fu Earl , Chen Hui‐Lin , Kung Suefang
Published: April 2008

Objectives: The purpose of this study was to evaluate the movement of pure titanium implants under different continuous forces in the edentulous alveolar ridge.

Material and methods: Four pairs of titanium implants were inserted into the right maxillary and mandibular post‐extraction edentulous ridge of the experimental dog. Three different levels of continuous force (100, 200, and 500 g) were loaded onto three pairs of adjacent implant abutments using a memory Ni–Ti coil spring for up to 6 months and the remaining two implant abutments as the control group received no force. The positions of implant abutments were observed and the distances between the implants abutment at the top, middle and base levels were measured at the 0th, 2nd, 3rd, 6th and 8th month of the follow‐up period.

Results: There was no significant change in the distances between adjacent abutments loaded with 100 or 200 g continuous forces throughout the entire study period. However, significantly more movement of implant abutments was noted in the 500 g pair after the 3rd month of loading when compared with the 200 or the 100 g pair (both P<0.001). This change further increased at the 6th month (P<0.001, 0.01, respectively). Moreover, the difference in the measurements at the top, middle and base level indicated that the two adjacent implants moved in a tipping manner in the 500 g pair after 3 and 6 months of loading.

Conclusion: The osseointegrated implants remained stable and rigid with a pulling force of 100 and 200 g after 6 months of loading. However, when the force reached 500 g, the implants moved in an inward‐tipping pattern. The results suggested that endosseous titanium implants might not necessarily be rigid anchorages under all circumstances.
Influence of homeopathic treatment with comfrey on bone density around titanium implants. A digital subtraction radiography study in rats
Authors: Sakakura Celso Eduardo , Neto Rubens Spin , Bellucci Marina , Wenzel Ann , Scaf Gulnara , Marcantonio Elcio
Published: April 2008

Objective: The objective of this study was to evaluate the influence of homeopathic treatment with comfrey (Shymphytum officinalis 6CH) on radiographic bone density and area around titanium implants.

Material and methods: Forty‐eight rats were divided into two groups of 24 animals each: a control group (C) and a test group (SO). Each animal received one titanium micro‐implant placed in the tibia. The animals in Group SO were subjected to 10 drops of comfrey 6CH per day mixed into their drinking water until the day of sacrifice. Eight animals of each group were sacrificed at 7, 14 and 28 days post‐surgery, respectively.

Standardized digital radiographs were obtained on the day of implant installation (baseline images) and on the day of sacrifice (final images). Digital subtraction of the two corresponding images was performed to evaluate changes in bone density and the area related to change around the implant between baseline and final images.

Results: Subtraction images demonstrated that a significant difference existed in mean shade of gray at 14 days post‐surgery between Group SO (mean 175.3±14.4) and Group C (mean 146.2±5.2). Regarding the area in pixels corresponding to the bone gain in Group SO, the differences observed between the sacrifice periods and groups were only significant at 7 days sacrifice between Group SO (mean 171.2±21.9) and Group C (mean 64.5±60.4).

Conclusion: Within the limits of this study, comfrey administration promotes an increase in radiographic bone density around titanium implants in the initial period of bone healing.
Bone regeneration after topical BMP‐2‐gene delivery in circumferential peri‐implant bone defects
Authors: Lutz Rainer , Park Jung , Felszeghy Endre , Wiltfang Jörg , Nkenke Emeke , Schlegel Karl Andreas
Published: April 2008

Objectives: The aims of this study were to evaluate the rate of bone formation and osseointegration after topical gene delivery with a liposomal vector system carrying bone morphogenetic protein (BMP)‐2 cDNA in combination with a collagen carrier and autologous bone as a carrier in freshly created peri‐implant bone defects.

Materials and methods: Eight domestic pigs received nine calvariae defects each (10 × 7 mm). A dental implant was inserted into the centre of each defect. In the test groups, the remaining space was filled with the liposomal vector/BMP‐2 complex combined with a collagen carrier (n=18) or an autologous bone graft (n=18). Control groups were collagen only (n=18) and autologous bone graft only (n=18).

Results: There was a significant difference in mineralisation rate in the BMP‐2/bone graft (29.9%± 4.8 and 68.3%± 7.2) and bone graft only (22.6%± 2.6 and 49.4%± 13.9) groups after 7 and 28 days. Mineralisation values were also significantly higher in the BMP‐2/collagen group (21.2%± 16.2 and 53.1%± 12.5) compared with the collagen‐only group (8.2%± 7 and 41%± 8.1) in two different regions after 28 days. Also the bone‐to‐implant contact was significantly increased in the BMP‐2/bone graft group after 28 days and in the BMP‐2/collagen group after 7 and 28 days compared with their control groups.

Conclusions: The results of this study show a significantly positive effect of liposomal vector/BMP‐2 on bone regeneration and osseointegration in bony circumferential peri‐implant defects.
Immediate non‐occlusal vs. early loading of dental implants in partially edentulous patients: a multicentre randomized clinical trial. Peri‐implant bone and soft‐tissue levels
Authors: Galli Fabio , Capelli Matteo , Zuffetti Francesco , Testori Tiziano , Esposito Marco
Published: April 2008

Objectives: To compare peri‐implant bone and soft‐tissue levels of immediately non‐occlusally loaded vs. non‐submerged early loaded implants in partially edentulous patients up to 14 months after placement.

Material and methods: Fifty‐two patients were randomized in five Italian private practices: 25 in the immediately loaded group and 27 in the early loaded group. To be immediately loaded, single implants had to be inserted with a torque of ≥30 N cm, and splinted implants with a torque of ≥20 N cm. Immediately loaded implants were provided with non‐occluding temporary restorations within 48 h. After 2 months, the provisional restorations were placed in full occlusion. Implants were early loaded after 2 months. Final restorations were provided 8 months after placement. Blinded assessors evaluated peri‐implant bone and soft‐tissue levels.

Results: Fifty‐two implants were immediately loaded and 52 were early loaded. No drop‐out occurred. One single immediately loaded implant failed 2 months after placement. Both groups gradually lost peri‐implant bone in a highly statistically significant manner at 2, 8, and 14 months. After 14 months, patients of both groups lost an average of 1.1 mm of peri‐implant bone. There were no statistically significant differences between the two loading strategies for peri‐implant bone and soft‐tissue level changes (P>0.05). After 14 months, the position of the soft tissues did not change significantly from baseline (delivery of the final restorations 8 months after placement).

Conclusions: There were no statistically or clinically significant differences between immediate and early loading of dental implants with regard to peri‐implant bone and soft‐tissue levels as evaluated in the present study.
Pedunculated hemangiopericytoma‐like tumor: peculiar fibroepithelial polyp or fibrous histiocytoma variant
Authors: Brown Jameel Ahmad , Morgan Michael B
Published: April 2008

Abstract:  Pathologists are continually challenged with the difficult task of discriminating between innocuous disease processes and potentially malignant entities. Apropos of this concern, we present a series of three cutaneous polypoid lesions that simulated fibroepithelial polyp, yet upon close scrutiny yielded histologic features of solitary fibrous tumor (SFT) or hemangiopericytoma. These pedunculated lesions showed a storiform pattern of spindled cells with interspersed gaping vascular channels reminiscent of SFT or hemangiopericytoma. Interestingly, the immunohistochemical staining profile of these lesions was negative for CD34 and positive for bcl‐2 and factor XIIIa. These findings were discordant with SFT and suggest a relationship with fibrous histiocytoma. We propose that this entity represents a hitherto described variant of fibrous histiocytoma known as pedunculated hemangiopericytoma‐like fibrous histiocytoma.
Review Article: Healthy ageing in rural Australia: Issues and challenges
Authors: Davis Sandra , Bartlett Helen
Published: April 2008

Approximately 36% of the rural Australian population is 65 years and older. In fact, many rural and remote communities have higher proportions of older people than metropolitan centres. The rate of growth, patterns of migration, higher levels of health risk factors and of social and economic disadvantage all impact on rural healthy ageing. Older people in rural communities have become marginalised by longstanding misconceptions about rural life and urban‐centric policies, much of which goes unchallenged because of a paucity of research in key areas and a lack of intrarural research. Understanding the complexities of rural healthy ageing is challenging, and more research is required to develop a stronger empirical base. The aim of this review is to critique the literature related to rural ageing in Australia to identify the issues and challenges for rural healthy ageing and implications for policy and practice.
Triplets of quasars as lighthouses of rich galaxy clusters
Authors: Söchting Ilona K. , Coldwell Georgina V. , Alonso M. Victoria , Smith Malcolm G. , Lambas Diego G.
Published: April 2008

In this Letter, we investigate the very large-scale environments of cluster-scale triplets of type 1 Seyfert galaxies, lower luminosity counterparts of quasars, detected at z < 0.2 in the fourth Data Release of the Sloan Digital Sky Survey. The search for cluster scale triplets (object-object separations <2.0 h−1 Mpc and <2000 km s−1) in a combined sample of Seyferts and quasars resulted in only 7 triplets, 3 of which are at z < 0.2. We investigated their environments and found a strong association of z < 0.2 triplets with the richest central parts of superclusters. In two out of three cases, the members of the triplets have been found on the periphery of an extremelly rich galaxy cluster (Abell class 2 and 3). The third triplet also appears associated with a very rich cluster of galaxies but on a somewhat larger scale. Nevertheless, on a small scale, it is still associated with a cluster but of lesser richness. These results suggest that triplets of type 1 Seyfert galaxies at low redshifts are excellent tracers of very rich clusters. Following these results we conclude that triplets of quasars, bright counterparts of type 1 Seyfert galaxies, may be the most successful means of finding distant, very rich, galaxy clusters.
EFFECT OF THERMOPHILIC LACTIC ACID BACTERIA ON THE FATE OF ENTEROBACTER SAKAZAKII DURING PROCESSING AND STORAGE OF PLAIN YOGURT
Authors: SHAKER REYAD R. , OSAILI TAREQ M. , AYYASH MUTAMED
Published: April 2008

Survival and growth of Enterobacter sakazakii during processing and storage of plain yogurt were investigated. Preheated rehydrated milk was inoculated with a cocktail culture of E. sakazakii (103 cfu/mL of milk) and/or with thermophilic yogurt starter culture of Lactobacillus delbrueckii ssp. bulgaricus and Streptococcus salivarius ssp. thermophilus. The inoculated milk was incubated at 40C for 5 h, then the samples were cooled and subsequently stored at 4C for up to 7 days. The results showed that E. sakazakii grew at an early stage of fermentation but declined at the end of the process. There was no significant difference between the populations of E. sakazakii in the presence or absence of lactic acid bacteria during the first 4 h of the incubation period but there was significant difference during the last hour of the incubation period. The populations of E. sakazakii decreased significantly during cooling and storage of yogurt (pH 4.2−4.7) compared with nonfermented milk samples at 4C. The presence of E. sakazakii did not have a significant effect on the growth of LAB during fermentation and storage of yogurt. The results obtained from this study indicate that the pH of yogurt and storage temperature were critical to the survival and growth of E. sakazakii in the manufacture of plain yogurt.

PRACTICAL APPLICATIONS

Enterobacter sakazakii prevalence in milk products and the production environment has been documented. The results obtained from this study may be of use to dairy producers to manufacture safe products using thermophilic lactic acid bacteria. These bacteria decreased the pH of milk in less than 5 h, resulting in E. sakazakii reduction. pH of yogurt during the fermentation process is a critical control point that should be monitored to produce safe products.
LISTERIA MONOCYTOGENES AND ESCHERICHIA COLI O157:H7 INHIBITION IN VITRO BY LIPOSOME‐ENCAPSULATED NISIN AND ETHYLENE DIAMINETETRAACETIC ACID
Authors: TAYLOR T. MATTHEW , BRUCE BARRY D. , WEISS JOCHEN , DAVIDSON P. MICHAEL
Published: April 2008

Encapsulation technologies that effectively reduce antimicrobial interaction with food components or protect antimicrobial compounds from food processing measures have the potential to improve the microbiological safety of ready‐to‐eat foods. Recent application of liposomes for the preservation of cheese has spurred research into their utility in other food matrices. To ascertain the feasibility of encapsulated antimicrobial for the control of Listeria monocytogenes and Escherichia coli O157:H7 growth in a model system, nisin (5.0 and 10.0 µg/mL) and the chelator ethylene diaminetetraacetic acid were entrapped in phospholipid liposomes. While phosphatidylcholine (PC) liposomes did not produce significant inhibition of target pathogens, PC/phosphatidylglycerol 8/2 and 6/4 (mol%) produced significant inhibition of pathogens. Near‐complete inhibition of E. coli O157:H7 with liposomal antimicrobials at concentrations below those reported necessary for unencapsulated antimicrobial and chelator suggests that liposomes may represent a powerful technology for the encapsulation of antimicrobials and the control of foodborne pathogens.

PRACTICAL APPLICATIONS

The activity of many antimicrobials is abolished in many food products for a variety of reasons. Interference and cross‐reactions of the antimicrobial and various food constituents, such as protein and fat, are difficult to overcome and often require large amounts of antimicrobial in order to gain significant reductions in the pathogen load in a product. Loss of solubility of some antimicrobials based on pH or ionic strength will negatively affect the antimicrobial potential of a compound like nisin. Liposome encapsulation technologies, such as that reported here, may allow for the maintenance of antimicrobial activity by protecting the antimicrobial against cross‐reactions with food components. Additionally, the liposome core represents a microenvironment which can be manipulated by the manufacturer in order to preserve optimal antimicrobial solubility and stability conditions until the time of release.
DEATH OF SALMONELLA SEROVARS, ESCHERICHIA COLI O157 : H7, STAPHYLOCOCCUS AUREUS AND LISTERIA MONOCYTOGENES DURING THE DRYING OF MEAT: A CASE STUDY USING BILTONG AND DROËWORS
Authors: BURNHAM GREG M. , HANSON DANA J. , KOSHICK CHARLOTTE M. , INGHAM STEVEN C.
Published: April 2008

Biltong and droëwors are ready‐to‐eat dried seasoned beef strips and sausages, respectively. Procedures to meet process lethality requirements for these products have not been validated. The fate of Salmonella serovars, Escherichia coli O157 : H7, Staphylococcus aureus, and Listeria monocytogenes was evaluated during the manufacture and vacuum‐packaged storage (7 days at 20–22C) of three lots each of biltong and droëwors. Acid‐adapted pathogens were used as inocula (ca. 7 log CFU per sample for each pathogen). The biltong manufacturing process reduced pathogen levels from 1.2 to 3.8 log CFU (S. aureus and L. monocytogenes, respectively). Less lethality was achieved in making droëwors, probably because of the higher fat content. The manufacturing processes for biltong and droëwors achieved significant lethality. Combined with additional intervention steps and/or raw material testing, the processes would achieve mandated levels of pathogen destruction.

PRACTICAL APPLICATIONS

The results of our experimental trials can be applied to commercial dried meat products with water activity, MPR, pH and % water‐phase salt at least as restrictive as our trial products. It was clear from our results that drying of seasoned beef strips or sausage would result in significant reduction in numbers for all four pathogens tested.
LYSIS OF VIBRIOS BY BDELLOVIBRIO‐AND‐LIKE ORGANISMS (BALOs) ISOLATED FROM MARINE ENVIRONMENT
Authors: CAI JUNPENG , ZHAO JUN , WANG ZHI , ZOU DIJING , SUN LIYING
Published: April 2008

Four marine Bdellovibrio‐and‐like organisms (BALOs), viz. BDW01, BDW02, BDW03 and BDW04, were isolated from the Shenzhen Bay of Guangdong province, China, using Vibrio parahaemolyticus (Vp) strain minus as the host bacterium. They were identified as BALOs by electron microscopy and specific polymerase chain reaction methods. Lysis experiments on 41 potentially pathogenic vibrios showed that individually, BDW01, BDW02, BDW03 and BDW04 lysed 36.6, 39.0, 65.8 and 63.4% vibrios, respectively. In combination, they lysed 87.8% of the vibrios tested. In terms of different vibrio species lysed, four BALOs combined could lyse 81.8% Vibrio alginolyticus (11 strains), 83.3% non‐O1 Vibrio cholerae (6 strains), 88.9% Vibrio fluvialis (9 strains), 100% Vibrio minicus (4 strains) and 88.9% Vp (9 strains). The results of this work clearly demonstrated the potential of BALOs in lysing potentially pathogenic vibrios.

PRACTICAL APPLICATIONS

Marine Bdellovibrio‐and‐like organisms (BALOs) have many potential applications, particularly in the seafood processing industry, seafood restaurants' and markets' aquaria as well as in marine aquaculture and in research laboratory where sterilization of live organisms is required. As vibrios, either pathogenic or potentially pathogenic, are ubiquitous in the marine environments, contamination of fish and/or shellfish with vibrios is unavoidable and very common. BALOs can therefore be employed to lyse vibrios in these circumstances via proper means. In our research (Cai et al. 2006), BALOs have successfully been applied to reduce Vibrio parahaemolyticus in oyster‐rearing environments in a laboratory scale. They have also been successfully applied, in place of antibiotics, to eliminate bacteria from some algae. Currently, the applications of BALOs in seafood restaurants' and markets' aquaria are under evaluation.
MICROBIOLOGICAL QUALITY OF FROZEN “EDAMAME” (VEGETABLE SOYBEAN)
Authors: PAO S. , ETTINGER M.R. , KHALID M.F. , MEBRAHTU T. , MULLINS C.
Published: April 2008

This study compared the microbiological quality of frozen “edamame” to other varieties of frozen beans sold in Virginia. Furthermore, the reduction of microorganisms during experimental edamame processing was investigated. Commercial frozen in‐pod and shelled edamame had aerobic mesophiles at 3.4 and 3.1 log cfu/g, yeasts and molds at 2.3 and 2.1 log cfu/g, and some contained low levels of Escherichia coli and enterotoxigenic Bacillus spp. Salmonellae were not found; however, 5% edamame and 4% frozen beans in general were positive for Listeria monocytogenes. Rinsing and shelling raw edamame caused a 1–2 log reduction of total aerobic mesophile, yeast and mold, and coliform counts. No naturally occurring yeast, mold or coliform was detected after blanching edamame at 98C for≥30 s. Blanching for 60 s eliminated approximately 6 log cfu/g of inoculated E. coli and Listeria from in‐pod edamame. Adequate processing ensures the microbial quality and safety of frozen edamame.

PRACTICAL APPLICATIONS

Frozen “edamame” has the potential to be produced with microbial quality acceptable for direct consumption. However, current products may contain harmful bacteria such as Escherichia coli and Listeria monocytogenes; thus, thorough reheating is required for consumer safety. Strict sanitation and effective blanching practices are critical in assuring microbial quality and safety of frozen edamame. Data reported for the first time from this current study could be used to inform frozen edamame producers and consumers of the potentially associated microbial hazards and adequate means for food protection.
How I do it: sample size calculations
Authors: O’Hara J.
Published: April 2008

Keypoints

Sample size calculations are integral to project design.

A description of the underlying theory behind them is set out.

Required are the significance level, the power, the clinical difference and the standard deviation.

Douglas Altman’s nomogram is particularly useful for sample size calculations for comparing independent samples.
Adaptive changes of the locomotor pattern and cutaneous reflexes during locomotion studied in the same cats before and after spinalization
Authors: Frigon Alain , Rossignol Serge
Published: April 2008

Descending supraspinal inputs exert powerful influences on spinal reflex pathways in the legs. Removing these inputs by completely transecting the spinal cord changes the state (i.e. the configuration of the spinal circuitry) of the locomotor network and undoubtedly generates a reorganization of reflex pathways. To study changes in reflex pathways after a complete spinalization, we recorded spinal reflexes during locomotion before and after a complete transection of the spinal cord at the 13th thoracic segment in cats. We chronically implanted electrodes in three cats, to record electromyography (EMG) in several hindlimb muscles and around the left tibial (Tib) nerve at the ankle to elicit reflexes during locomotion before and after spinalization in the same cat. Control values of kinematics, EMGs and reflexes were obtained during intact locomotion for 33–60 days before spinalization. After spinalization, cats were trained 3–5 times a week on a motorized treadmill. Recordings resumed once a stable spinal locomotion was achieved (26–43 days), with consistent plantar foot placement and full hindquarter weight support without perineal stimulation. Changes in Tib nerve reflex responses after spinalization in the same cat during locomotion were found in all muscles studied and were often confined to specific phases of the step cycle. The most remarkable change was the appearance of short‐latency excitatory responses in some ipsilateral ankle extensors during stance. Short‐latency excitatory responses in the ipsilateral tibialis anterior were increased during stance, whereas in other flexors such as semitendinosus and sartorius, increases were mostly confined to swing. Longer‐latency excitatory responses in ipsilateral flexors were absent or reduced. Responses evoked in limb muscles contralateral to stimulation were generally increased throughout the step cycle. These reflex changes after spinalization provide important clues regarding the functional reorganization of reflex pathways during spinal locomotion.
Fracture Propagation to the Base of the Greenland Ice Sheet During Supraglacial Lake Drainage
Authors: Das Sarah B. , Joughin Ian , Behn Mark D. , Howat Ian M. , King Matt A. , Lizarralde Dan , Bhatia Maya P.
Published: April 2008

Surface meltwater that reaches the base of an ice sheet creates a mechanism for the rapid response of ice flow to climate change. The process whereby such a pathway is created through thick, cold ice has not, however, been previously observed. We describe the rapid (<2 hours) drainage of a large supraglacial lake down 980 meters through to the bed of the Greenland Ice Sheet initiated by water-driven fracture propagation evolving into moulin flow. Drainage coincided with increased seismicity, transient acceleration, ice-sheet uplift, and horizontal displacement. Subsidence and deceleration occurred over the subsequent 24 hours. The short-lived dynamic response suggests that an efficient drainage system dispersed the meltwater subglacially. The integrated effect of multiple lake drainages could explain the observed net regional summer ice speedup.
Prescription writing skills of residents in a family practice residency programme in Bahrain
Authors: Khaja K A J Al , Sequeira R P , Al-Ansari T M , Damanhori A H H
Published: April 2008

Purpose of the study

To evaluate the prescription writing skill of final year residents in a family practice residency programme (FPRP) in Bahrain, and to compare skill of residents who have graduated from medical schools with problem based learning (PBL) versus traditional (non-PBL) curricula.

Study design

Prescriptions issued by the residents were prospectively collected for two consecutive cohorts in May 2004 and May 2005. Prescription errors were classified as errors of omission (minor and major), commission (incorrect information) and integration (drug–drug interactions).

Results

In 69.6% of medications with major omission errors, dosage form (39.4%) and length of treatment (18.5%) were not specified. In 24.7% of medications with commission errors, dosing frequency (19.9%) and incorrect strength/dose (2.2%) were the most common errors. Integration errors comprised 5.7% of all prescribing errors. No significant differences were observed between PBL and non-PBL graduates with regard to the total number of prescriptions with errors, drugs per prescription, polypharmacy, and the total number of drugs with errors. The proportion of prescriptions with a potential for drug–drug interactions was comparable between PBL and non-PBL graduates. PBL graduates prescribed medications using brand names at a rate greater than non-PBL, whereas non-PBL graduates prescribed medications on inappropriate “as required” basis, and injections at a rate greater than PBL residents.

Conclusions

Prescription writing skill of the final year residents in an FPRP programme was suboptimal for both PBL and non-PBL graduates. Integration of prescription writing skill and a rational pharmacotherapeutic programme into the FPRP curriculum is recommended.
Prognostic significance of genotyping Helicobacter pylori infection in patients in younger age groups with gastric cancer
Authors: Tiwari S K , Manoj G , Kumar G Vasanth , Sivaram G , Hassan S I , Prabhakar B , Devi U , Jalaluddin S , Kumar K , Ahmed S , Abid Z , Habeeb M A , Khan A A , Habibullah C M
Published: April 2008

Background

Malignant tumours of the stomach are common, but the incidence of stomach cancer varies from country to country, probably a result of genetic, epigenetic and environmental factors. Stomach cancer often occurs in older people whose stomachs produce only small quantities of acid. Although infection with Helicobacter pylori has been proven beyond doubt in the aetiopathogenesis of various gastric disorders, not much is known about the genotypes of H pylori infection in early-onset gastric cancer.

Aim

To ascertain the genotypes of H pylori in gastric cancer.

Methods

Ninety-two patients were separated into three groups on the basis of their endoscopic findings: group 1, gastric cancer; group 2, gastric ulcer; group 3, non-ulcer dyspepsia. Gastric biopsy specimens were obtained for culture and DNA isolation; additional specimens were taken from subjects with gastric cancer for histopathological analysis. Amplification was performed using specific oligonucleotide primers to obtain genotypic data. Four samples from each group were randomly selected for sequence analysis.

Results

Genotypic analysis showed cagT+ve/hrgA+ve/cagA+ve/cagE+ve/vacAs1+ve to be highly prevalent in 79% of cases of H pylori infection. This genotype was found in 88% of subjects in group 1 and 78% in group 2. Intestinal-type adenocarcinoma was found in 35 subjects (83%), 32 (9%) of which harboured this genotype. Sequence analysis showed no significant strain-specific variations.

Conclusions

Certain genotypes of H pylori have higher predictive value for the development of intestinal-type carcinoma at an early age. Genotyping of H pylori may well be a useful tool for screening people at increased risk of developing malignancy.
Drug interaction with anti-mycobacterial treatment as a cause of clopidogrel resistance
Authors: Srinivasan M , Smith D
Published: April 2008

The case is reported of a patient presenting with recurrent acute myocardial infarction due to stent thrombosis resulting from possible clopidogrel resistance caused by interaction between clopidogrel and anti-tuberculosis drugs. A brief overview of drug interaction as a risk factor for clopidogrel resistance is given.
Developmental morphology of the flower of Anthurium jenmanii: a new element in our understanding of basal Araceae
Authors: Barabé Denis , Lacroix Christian
Published: April 2008

The early stages of development of the inflorescence of Anthurium jenmanii Engl. were examined using scanning electron microscopy. The inflorescence of A. jenmanii consists of more than 100 flowers arranged in recognizable spirals. Each flower has four broad tepals enclosing four stamens that are not visible prior to anthesis. The gynoecium consists of two carpels. The floral primordia are first initiated on the lower portion of the inflorescence, they then increase in size and appear as transversely extended bulges. The two lateral tepals are the first organs to be initiated, followed shortly thereafter by the two median tepals. The two lateral stamens are initiated first, directly opposite the lateral tepals, and are followed by two median stamens initiated directly opposite the median tepals. A two-lobed stigma is clearly visible during the early stages of development of the gynoecium. On some of the young inflorescences, all floral parts were covered by extracellular calcium oxalate crystals. The release of these prismatic crystals occurs before the stamens and petals have reached maturity. The mode of floral development observed in Anthurium has similarities with that reported for Gymnostachys . However, contrary to Gymnostachys, the development of the flower of A. jenmanii is not unidirectional.
Parallel patterns of clinal variation inSolidago altissimain its native range in central USA and its invasive range in Japan
Authors: Etterson Julie R. , Delf Daniel E. , Craig Timothy P. , Ando Yoshino , Ohgushi Takayuki
Published: April 2008

The ability of exotic species to proliferate and expand their range may hinge critically upon their potential for adaptive evolution. The finding of parallel patterns of genetically based clinal variation in native and non-native ranges across similar environmental gradients supports the hypothesis that adaptive evolution has played a role in establishment and spread. In this common garden study, we compared patterns of phenotypic variation among 12 populations of Solidago altissima L. that were sampled across similar latitudes in the native range in central USA (25°N–43°N) and across its invasive range in Japan (26°N–43°N). Significant clinal variation in phenotype corresponding to latitude was found among US and Japanese populations for height, leaf number, leaf length, leaf width, stem diameter, and stomatal guard-cell size. Only the slope of leaf width differed significantly between the native and invasive range, and the slope was significantly steeper in Japan. These results indicate that patterns of selection across latitude are similar in these two countries. We suggest that populations of S. altissima have rapidly differentiated in response to the cline in selection in Japan, possibly by the sorting of lineages from multiple introductions, and this has contributed to their success as an exotic invader.
APPROXIMATE VORTEX SOLUTION OF FADDEEV MODEL
Authors: SHI CHANG-GUANG , HIRAYAMA MINORU
Published: April 2008

Through an ansatz specifying the azimuthal-angle dependence of the solution, the static field equation for vortex of the Faddeev model is converted to an algebraic ordinary differential equation. An approximate analytic expression of the vortex solution is explored so that the energy per unit vortex length becomes as small as possible. It is observed that the minimum energy of vortex is approximately proportional to the integer which specifies the solution.
CONSISTENT DEFORMED BOSONIC ALGEBRA IN NONCOMMUTATIVE QUANTUM MECHANICS
Authors: ZHANG JIAN-ZU
Published: April 2008

In two-dimensional noncommutative space for the case of both position–position and momentum–momentum noncommuting, the consistent deformed bosonic algebra at the nonperturbation level described by the deformed annihilation and creation operators is investigated. A general relation between noncommutative parameters is fixed from the consistency of the deformed Heisenberg–Weyl algebra with the deformed bosonic algebra. A Fock space is found, in which all calculations can be similarly developed as if in commutative space and all effects of spatial noncommutativity are simply represented by parameters.
GRAVITY AND ITS MYSTERIES: SOME THOUGHTS AND SPECULATIONS
Authors: ZEE A.
Published: April 2008

I gave a rambling talk about gravity and its many mysteries at Chen-Ning Yang's 85th Birthday Celebration held in November 2007. I do not have any answers.
Trends in the Development of New Mg Alloys
Authors: Bamberger M. , Dehm G.
Published: April 2008

Advanced Mg alloys require a stable microstructure that maintains good mechanical properties when exposed to high temperatures. On the basis of this demand, the search for new Mg alloys has stimulated the imagination of material scientists. This review's discussion ranges from modifications of commercial Mg-Al- and Mg-Zn-based alloys by Ca and rare earth (RE) elements to the investigations of new families of Mg alloys based on Mg-Sn and Mg-Gd. It reports the fundamental findings of these efforts, including microstructure, mechanical properties, and strengthening mechanisms.
EGF receptor tyrosine kinase inhibitors diminish transforming growth factor-α-induced pulmonary fibrosis
Authors: Hardie William D. , Davidson Cynthia , Ikegami Machiko , Leikauf George D. , Le Cras Timothy D. , Prestridge Adrienne , Whitsett Jeffrey A. , Korfhagen Thomas R.
Published: April 2008

Transforming growth factor-α (TGF-α) is a ligand for the EGF receptor (EGFR). EGFR activation is associated with fibroproliferative processes in human lung disease and animal models of pulmonary fibrosis. We determined the effects of EGFR tyrosine kinase inhibitors gefitinib (Iressa) and erlotinib (Tarceva) on the development and progression of TGF-α-induced pulmonary fibrosis. Using a doxycycline-regulatable transgenic mouse model of lung-specific TGF-α expression, we determined effects of treatment with gefitinib and erlotinib on changes in lung histology, total lung collagen, pulmonary mechanics, pulmonary hypertension, and expression of genes associated with synthesis of ECM and vascular remodeling. Induction in the lung of TGF-α caused progressive pulmonary fibrosis over an 8-wk period. Daily administration of gefitinib or erlotinib prevented development of fibrosis, reduced accumulation of total lung collagen, prevented weight loss, and prevented changes in pulmonary mechanics. Treatment of mice with gefitinib 4 wk after the induction of TGF-α prevented further increases in and partially reversed total collagen levels and changes in pulmonary mechanics and pulmonary hypertension. Increases in expression of genes associated with synthesis of ECM as well as decreases of genes associated with vascular remodeling were also prevented or partially reversed. Administration of gefitinib or erlotinib did not cause interstitial fibrosis or increases in lavage cell counts. Administration of small molecule EGFR tyrosine kinase inhibitors prevented further increases in and partially reversed pulmonary fibrosis induced directly by EGFR activation without inducing inflammatory cell influx or additional lung injury.
The endocrine response and substrate utilization during exercise in children and adolescents
Authors: Riddell Michael C.
Published: April 2008

Adolescence is a time of rapid growth caused by significant changes in hormone levels. For many, it is also a time of increased physical activity and sport that places a large demand on energy reserves. Exercise is known to cause perturbations in endocrine and metabolic systems in children and adolescents, yet careful characterization of these responses is only now being conducted. It does not appear that prepubertal youth have a different muscle composition than adults. However, these youth do have a lower anaerobic capacity and a greater reliance on aerobic metabolism during activity. Prepubertal adolescents may have an immature glucose regulatory system that influences glycemic regulation at the onset of moderate exercise. During heavy exercise, muscle and blood lactate levels are lower in children than in adults and there is a greater reliance on fat as fuel. The exercise intensity that causes maximal fat oxidation rate and the relative rate of fat oxidation decreases as adolescents develop through puberty. The mechanism for the attenuated lipid utilization with the advancement of puberty, and the impact that this may have on body composition, are unknown. Surprisingly, prepubertal adolescents have relatively high rates of exogenous glucose oxidation, perhaps because of their smaller endogenous carbohydrate reserves. Further study is needed to determine the optimal exogenous carbohydrate feeding regimen for peak performance in adolescence. Studies are also needed to determine whether physical activity, at an intensity targeted to maximize fat oxidation, help to lower body adiposity in overweight youth.
Some aspects of clinical relevance in the maturation of respiratory control in infants
Authors: Thach Bradley T.
Published: April 2008

Two reflex mechanisms important for survival are discussed. Brain stem and cardiovascular mechanisms that are responsible for recovery from severe hypoxia (autoresuscitation) are important for survival in acutely hypoxic infants and adults. Failure of this mechanism may be important in sudden infant death syndrome (SIDS), because brain stem-mediated hypoxic gasping is essential for successful autoresuscitation and because SIDS infants appear to attempt to autoresuscitate just before death. A major function of another mechanism is to protect the airway from fluid aspiration. The various components of the laryngeal chemoreflex (LCR) change during maturation. The LCR is an important cause of prolonged apneic spells in infants. Consequently, it also may have a role in causing SIDS. Maturational changes and/or inadequacy of this reflex may be responsible for pulmonary aspiration and infectious pneumonia in both children and adults.
Single bouts of exercise affect albumin redox state and carbonyl groups on plasma protein of trained men in a workload-dependent manner
Authors: Lamprecht Manfred , Greilberger Joachim F. , Schwaberger Guenther , Hofmann Peter , Oettl Karl
Published: April 2008

The purpose of this study was to investigate the effect of single bouts of exercise at three different intensities on the redox state of human serum albumin (HSA) and on carbonyl groups on protein (CP) concentrations in plasma. Trained men [ n = 44, maximal oxygen consumption (V̇o2max): 55 ± 5 ml·kg−1·min−1, nonsmokers, 34 ± 5 years of age] from a homogenous population, volunteers from a police special forces unit, were randomly assigned to perform on a cycle ergometer either at 70% ( n = 14), 75% ( n = 14), or 80% ( n = 16) of V̇o2max for 40 min. Blood was collected before exercise, immediately after the exercise test (IE), and 30 min after each test (30M) and 30 h after each test (30H). The reduced fraction of HSA, human mercaptalbumin (HMA), decreased at all three exercise intensities IE and 30M, returning to preexercise values by 30H ( P < 0.05). HMA was primarily oxidized to its reversible fraction human nonmercaptalbumin 1 (HNA1). CP concentrations increased at 75% of V̇o2max IE and 30M with a tendency ( P < 0.1) and at 80% V̇o2max IE and 30M significantly, returning to preexercise concentrations by 30H ( P < 0.01). These results indicate that the HSA redox system in plasma is activated after a single bout of cycle ergometer exercise at 70% V̇o2max and 40 min duration. The extent of the HSA modification increased with exercise intensity. Oxidative protein damage, as indicated by CP, was only significantly increased at 80% V̇o2max intensity in this homogenous cohort of trained men.
Ccl2/Cx3cr1-Deficient Mice: An Animal Model for Age-Related Macular Degeneration
Authors: Chan Chi-Chao , Ross Robert J. , Shen Defen , Ding Xiaoyan , Majumdar Zigurts , Bojanowski Christine M. , Zhou Min , Salem, Jr. Norman , Bonner Robert , Tuo Jingsheng
Published: April 2008

Background/Aims: Senescent Ccl2–/– mice develop cardinal features of human age-related macular degeneration (AMD). Loss-of-function single-nucleotide polymorphisms within CX3CR1 are associated with AMD. Methods: We generated Ccl2–/–/Cx3cr1–/– [double-knockout (DKO)] mice and evaluated the eyes using fundoscopy routine histology, immunochemistry, biochemistry and proteomics. Results: At 6 weeks old, all DKO mice developed AMD-like retinal lesions such as abnormal retinal pigment epithelium cells, drusen, photoreceptor atrophy and choroidal neovascularization, which progressed with age and reversed with high omega-3 long-chain polyunsaturated fatty acid diet. N-retinylidene-N-retinylethanolamine (A2E), a major lipofuscin fluorophore, illustrated by an emission peak at ∼600 nm, was significantly higher in DKO retinal pigment epithelium. Decreased ERp29 was found in the retina of DKO mice. Conclusion: A broad spectrum of AMD pathologies with early onset and high penetrance in these mice implicate certain chemokines, A2E and endoplasmic reticulum proteins in AMD pathogenesis.
Pathological Aspects of Spontaneous Uveitis and Retinopathy in HLA-A29 Transgenic Mice and in Animal Models of Retinal Autoimmunity: Relevance to Human Pathologies
Authors: de Kozak Yvonne , Camelo Serge , Pla Marika
Published: April 2008

Purpose: A major increased risk of developing birdshot chorioretinopathy is reported in humans who are HLA-A29-positive. To better characterize this disease, an animal model of HLA-A29-associated disease was developed and the pathology arising spontaneously in these transgenic mice was compared to animal models of autoimmune uveoretinitis and to human pathology. Materials and Methods: HLA-A2902 cDNA (A29c) was obtained from a patient suffering from birdshot retinochoroidopathy and used for transgene construct to generate HLA-A29 transgenic mice. Histopathological examination of the animal cohort was performed up to 15 months of age. It was compared with the ocular pathology developed in C57BL/6 mice and in Lewis rats immunized with retinal autoantigens. Results: Aging HLA-A29 transgenic mice spontaneously developed an ocular disease with resemblance to experimental retinal-Ag-induced autoimmune ocular disease and to human pathologies shown in birdshot retinochoroidopathy, Vogt-Koyanagi-Harada and sympathetic ophthalmia. Pathogenic mechanisms could possibly be shared by these conditions. Conclusion: Humanized models of ocular inflammation developed in HLA class I and class II transgenic mice will help better understand the mechanisms responsible for ocular inflammation. Local control of autoimmunity in HLA-A29-positive individuals would be an important option for new therapeutic strategies.
Microbial Products Trigger Autoimmune Ocular Inflammation
Authors: Fujimoto Chiaki , Shi Guangpu , Gery Igal
Published: April 2008

Purpose: Microbial products stimulate the immune system by interacting with Toll-like receptors (TLR) on antigen-presenting cells. This study examined the hypothesis that microbial products, which function as TLR ligands, are playing a major role in triggering pathogenic autoimmunity. Methods: An experimental system was developed in which microbial TLR ligands were tested in vivo for their capacity to stimulate naïve CD4 cells specific against hen egg lysozyme (HEL) to become effector cells capable of inducing inflammation in eyes in which HEL is expressed. The ligands’ mode of action was analyzed by determining their effects on the proliferation, acquisition of tissue-invading capacity, i.e. elevated CD49d and decreased CD62L expression, and production of interferon-γ by the HEL-specific cells. Results: All the 7 tested TLR ligands triggered ocular inflammation in the experimental system used here, with pertussis toxin surpassing all other ligands in its activities. A correlation was found between the capacity of the ligands to trigger pathogenic immunity and to stimulate the proliferation, modification of cell surface and interferon-γ production by T cells. Conclusions: This study provides direct evidence to support the notion that microbial products are capable of triggering pathogenic autoimmunity.
PlGF-1 and VEGFR-1 Pathway Regulation of the External Epithelial Hemato-Ocular Barrier
Authors: Miyamoto N. , de Kozak Y. , Normand N. , Courtois Y. , Jeanny J.C. , BenEzra D. , Behar-Cohen F.
Published: April 2008

VEGF is considered as an important factor in the pathogenesis of macular edema. VEGF induces the rupture of the blood retinal barrier and may also influence the retinal pigment epithelial (RPE) outer retinal barrier. The aim of this work was to analyze the influence of the VEGF receptor pathways in the modulation of the RPE barrier breakdown in vitro and in vivo. The ARPE19 human junctions in culture are modulated by VEGF through VEGFR-1 but not through VEGFR-2. PlGF-1, that is a pure agonist of VEGFR-1, is produced in ARPE-19 cells under hypoxic conditions and mimics VEGF effects on the external retinal barrier as measured by TER and inulin flux. In vivo, the intravitreous injection of PlGF-1 induces a rupture of the external retinal barrier together with a retinal edema. This effect is reversible within 4 days. VEGF-E, that is a pure agonist of VEGFR-2, does not induce any acute effect on the RPE barrier. These results demonstrate that PlGF-1 can reproduce alterations of the RPE barrier occurring during diabetic retinopathy.