bluuebunny/crossref_metadata_2025 huggingface dataset:
Periodontal healing in one‐wall intra‐bony defects in dogs following implantation of autogenous bone or a coral‐derived biomaterial
Authors: Kim Chang‐Sung , Choi Seong‐Ho , Cho Kyoo‐Sung , Chai Jung‐Kiu , Wikesjö Ulf M. E. , Kim Chong‐Kwan
Published: May 2005

Aim: Autogenous bone grafts and bone biomaterials are being used as part of protocols aiming at reconstruction of periodontal defects. There is a limited biologic information on the effect of such materials on periodontal healing, in particular aberrant healing events that may prevent their general use. The objective of this study was, using histological techniques, to evaluate periodontal healing with focus on root resorption and ankylosis following implantation of autogenous bone and a coral‐derived biomaterial into intra‐bony defects in dogs.

Methods: One‐wall intra‐bony periodontal defects were surgically created at the distal aspect of the second and the mesial aspect of the fourth mandibular premolars in either right or left jaw quadrants in four Beagle dogs. Each animal received particulated autogenous bone and the resorbable calcium carbonate biomaterial into discrete one‐wall intra‐bony defects. The mucoperiosteal flaps were positioned and sutured to their pre‐surgery position. The animals were euthanized 8 weeks post‐surgery when block sections of the defect sites were collected and prepared for qualitative histological analysis.

Results: There were no significant differences in periodontal healing between sites receiving autograft bone and the coral‐derived biomaterial. A well‐organized periodontal ligament bridging new bone and cementum regeneration was observed extending coronal to a notch prepared to delineate the apical extent of the defect. Osteoid and bone with enclosed osteocytes were formed onto the surface of both autograft and coral particles. Although small resorption pits were evident in most teeth, importantly none of the biomaterials provoked marked root resorption. Ankylosis was not observed.

Conclusion: Particulated autogenous bone and the coral‐derived biomaterial may be implanted into periodontal defects without significant healing aberrations such as root resorption and ankylosis. The histopathological evaluation suggests that the autogenous bone graft has a limited osteogenic potential as demonstrated in this study model.
Clinical and microbiological evaluation of the effectiveness of the Nd:Yap laser for the initial treatment of adult periodontitis
Authors: Ambrosini Pascal , Miller Neal , Briançon Serge , Gallina Sébastien , Penaud Jacques
Published: May 2005

Background: Enhancement of the results obtained by scaling and planing is most often sought by using antimicrobial therapies. Laser beams have been shown to be bactericidal and could possibly target pathogens more effectively and with fewer compliance problems than antiseptic solutions.

Methods: Thirty subjects 20–60 years old presenting periodontal pockets at least 5 mm deep in each quadrant received initial periodontal treatment. The study had a split‐mouth design. The control side (SRP) only received scaling and planing, and the test side (SRP+laser) was treated by both SRP and Nd:Yap (yttrium aluminum perovskite doped with neodym) laser. Clinical conditions were evaluated at day 0 and day 90 using the plaque index, gingival index, bleeding on probing, pocket probing depth, and clinical attachment level. Microbial sampling was also performed on days 0 and 90, and the presence of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythensis, and Treponema denticola was analysed by polymerase chain reaction in a commercial laboratory. Post‐operative pain or discomfort was measured by the patient using a linear visual scale. Pearson's chi‐squared test was used to compare bacterial presence.

Results: There was no statistically significant difference concerning clinical data between test and control groups at baseline. Both treatments enhanced the clinical situation compared to baseline; however, results were not significantly different between the two groups. T. forsythensis was the organism most numerous in both groups. Though initial treatment diminished the numbers of all the pathogens it did not do so statistically significantly. Differences between test and control groups were very small and bore no significance. Evaluation of the post‐operative pain did not reveal any differences between the groups.

Conclusions: Scaling and root planing was effective in reducing levels of plaque, inflammation, and bleeding upon probing. No additional advantage was achieved by using the Nd:Yap laser.
Melanoma cell lines are susceptible to histone deacetylase inhibitor TSA provoked cell cycle arrest and apoptosis
Authors: Peltonen Karita , Kiviharju Taija M. , Järvinen Päivi M. , Ra Runar , Laiho Marikki
Published: May 2005

Melanoma is the most aggressive of skin cancers because of its high resistance to currently available therapy. Although melanoma cells often retain wild‐type p53 tumour suppressor protein and express it at high levels, the p53 mediated apoptosis pathway is suppressed. Histone deacetylase (HDAC) inhibitors are a promising group of compounds inducing differentiation, growth arrest and apoptosis in tumour cells in preclinical studies. We have studied the cellular effects of trichostatin A (TSA), a HDAC inhibitor, in a panel of melanoma cell lines and its mechanism of action in relation to p53. TSA stabilized wild‐type p53, but p53 protein accumulation was overridden by simultaneous downregulation of p53 mRNA leading to a decrease in p53 protein. While growth arrest was induced in all cell lines studied and apoptosis in most (6/7), these cellular effects were independent of the p53 status of the cells. Inhibiting p53 function by a dominant negative p53 (p53175His) confirmed that the HDAC inhibitor induced apoptosis was independent of wild‐type p53, even though TSA slightly activated p53 in a reporter assay. The results indicate that while the action of TSA is independent of p53, the activation of the apoptosis pathway by the HDAC inhibitors may provide therapeutic approaches for melanoma treatment.
Histone deacetylase inhibitors and malignant melanoma
Authors: Boyle Glen M. , Martyn Adam C. , Parsons Peter G.
Published: May 2005

The search for antimelanoma agents acting by terminal differentiation via the pigmentation pathway has so far been unsuccessful, in part because of tumor heterogeneity and loss of function of pigmentation genes. Some differentiation agents, however, have emerged as inhibitors of histone deacetylases (HDAC), with consequences for chromosome remodeling, cell cycle arrest and selective toxicity in cultured melanoma cells compared with normal melanocytes. Few effects have been found on pigmentation, except paradoxically the down‐regulation of TRP‐1. Of the many genes regulated by HDAC inhibitors, induction of p21WAF1/Cip1 is the most consistent finding and is associated with G1 or G2 phase blocks. Some melanoma cell lines appear to lack an HDAC inhibitor‐specific G2 checkpoint and viability is thus compromised by dividing with inappropriately‐modified chromatin. Most cultured melanoma cells undergo apoptosis following treatment with HDAC inhibitors, via a mitochondrial and caspase‐dependent pathway. However, the molecular mechanism may vary with cell line and HDAC inhibitor class. Tumor selectivity cannot yet be attributed to specific types or levels of HDACs, nor has the possibility of acetylation of non‐histone targets been excluded. Elucidation of these complexities may be rewarding, in terms of directing the multiple consequences of inhibiting histone deacetylation towards overcoming the therapeutic problems of melanoma heterogeneity and emergence of resistance. Success in the clinic may require combination with agents that synergize with the cell cycle blocking and pro‐apoptotic action of HDAC inhibitors.
Dynamic regulation of the human dopachrome tautomerase promoter by MITF, ER‐α and chromatin remodelers during proliferation and senescence of human melanocytes
Authors: Schwahn Denise J. , Timchenko Nikolai A. , Shibahara Shigeki , Medrano Estela E.
Published: May 2005

Senescent cells are known to display altered gene expression of differentiation‐associated genes. We have previously demonstrated that the melanocyte transcriptional regulator microphthalmia‐associated protein (MITF) is down‐regulated in senescent melanocytes. Since virtually nothing is known regarding the differentiated function of senescent melanocytes, we analyzed the transcriptional regulation of Dopachrome tautomerase (DCT), a member of the tyrosinase gene family, in proliferating and in senescent human melanocytes. Computational analysis of the region containing the M‐box that includes the MITF CATGTG binding motif demonstrated that this sequence overlaps with the estrogen receptor alpha (ER‐α), USF‐1, TFE‐3, Isl‐1 and AP‐1 binding elements. Electrophoresis gel‐shift analysis using an oligonucleotide containing MITF and ERE elements identified MITF and ER‐α complexes in proliferating melanocytes, whereas only ER‐α complexes were detected in senescent cells. Importantly, a promoter‐reporter analysis demonstrated that the coactivator p300/CBP switched MITF from a repressor to an activator of DCT transcription. p300/CBP was also required by ER‐α and MITF to induce high, synergistic activation of the DCT promoter. We have also found that transcription of the DCT gene is differentially regulated by major melanocyte mitogens. In contrast to the activating effect of cAMP inducers, 12‐O‐tetradecanoylphorbolacetate (TPA) was a potent repressor of DCT transcription, suggesting that this gene can be differentially regulated by multiple environmental signals and promoter context. In support of this conclusion, trichostatin A, a histone deacetylase inhibitor, counteracted the TPA‐mediated repression, and restored high levels of DCT protein in cultured melanocytes. We conclude that senescent melanocytes display dramatic changes in the expression of differentiation‐related proteins; such changes may in turn result in altered melanocyte function and survival to environmental stresses.
Ednrb2 orients cell migration towards the dorsolateral neural crest pathway and promotes melanocyte differentiation
Authors: Pla Patrick , Alberti Christophe , Solov'eva Olga , Pasdar Manijeh , Kunisada Takahiro , Larue Lionel
Published: May 2005

Endothelin receptors B (Ednrb) are involved in the development of the enteric and melanocytic lineages, which originate from neural crest cells (NCCs). In mice, trunk NCCs and their derivatives express only one Ednrb. In quail, trunk NCCs express two Ednrb: Ednrb and Ednrb2. Quail Ednrb is expressed in NCCs migrating along the ventral pathway, which gives rise to the peripheral nervous system, including enteric ganglia. Ednrb2 is upregulated in NCCs before these cells enter the dorsolateral pathway. The NCCs migrating along the dorsolateral pathway are melanocyte precursors. We analyzed the in vitro differentiation and in ovo migration of mouse embryonic stem (ES) cells expressing and not expressing Ednrb2. We generated a series of transfected ES cell lines expressing Ednrb2. This receptor, like Ednrb, oriented genuine ES cells towards melanocyte lineage differentiation in vitro. The in ovo migration of Ednrb2‐expressing ES cells was massively oriented towards the dorsolateral pathway, unlike that of WT or Ednrb‐expressing ES cells. Thus, Ednrb2 is involved in melanoblast differentiation and migration.
Eumelanin and pheomelanin concentrations in human epidermis before and after UVB irradiation
Authors: Hennessy Alison , Oh Carol , Diffey Brian , Wakamatsu Kazumasa , Ito Shosuke , Rees Jonathan
Published: May 2005

Pheomelanin is widely thought to be causally related to susceptibility to the harmful effects of ultraviolet radiation: epidemiological studies show that those with a higher ratio of pheomelanin to eumelanin in hair have higher rates of melanoma, and work in mouse and cell culture shows that pheomelanin generates excess free radicals after UVR exposure. By contrast, based on measurements of eumelanin and pheomelanin in human skin, before and following irradiation, we now report that both pheomelanin and eumelanin are positively related to skin colour, and by inference, inversely with cancer susceptibility. The ratio of melanin classes is similar in people with widely different cancer rates and UVR sensitivity. Although our numbers are small, our results extend previous work in man, and lead us to speculate that factors other than the amount of pheomelanin may be important in determining UVR susceptibility in persons with red hair.
Adhesion, migration and communication in melanocytes and melanoma
Authors: Haass Nikolas K. , Smalley Keiran S. M. , Li Ling , Herlyn Meenhard
Published: May 2005

Under normal conditions, homeostasis determines whether a cell remains quiescent, proliferates, differentiates, or undergoes apoptosis. In this state of homeostasis, keratinocytes control melanocyte growth and behaviour through a complex system of paracrine growth factors and cell–cell adhesion molecules. Alteration of this delicate homeostatic balance and can lead to altered expression of cell–cell adhesion and cell communication molecules and to the development of melanoma. Melanoma cells escape from this control by keratinocytes through three major mechanisms: (1) down‐regulation of receptors important for communication with keratinocytes such as E‐cadherin, P‐cadherin, desmoglein and connexins, which is achieved through growth factors produced by fibroblasts or keratinocytes; (2) up‐regulation of receptors and signalling molecules not found on melanocytes but important for melanoma–melanoma and melanoma–fibroblast interactions such as N‐cadherin, Mel‐CAM, and zonula occludens protein‐1 (ZO‐1); (3) loss of anchorage to the basement membrane because of an altered expression of the extracellular‐matrix binding integrin family. In the current review, we describe the alterations in cell–cell adhesion and communication associated with melanoma development and progression, and discuss how a greater understanding of these processes may aid the future therapy of this disease.
Evaluation of general joint laxity, shoulder laxity and mobility in competitive swimmers during growth and in normal controls
Authors: Jansson Anna , Saartok Tönu , Werner Suzanne , Renström Per
Published: May 2005

The aim of the study was to evaluate differences between competitive swimmers and a reference group of school children concerning general joint laxity, laxity of the glenohumeral joint and range of motion in the shoulder. Materials and methods. Competitive swimmers (n=120) were compared with references consisting of age and gender matched school children (n=1277). General joint laxity was evaluated with the Beighton score. Anterior glenohumeral laxity was assessed according to the drawer test, and inferior glenohumeral laxity according to the sulcus test. Shoulder rotation was measured with a goniometer.

Results. Male swimmers of both age groups showed a higher degree of general joint laxity compared with the reference group while 9‐year‐old female swimmers alone had a lower degree of general joint laxity compared with references. No significant difference concerning shoulder laxity was noticed between groups. There was a decreased internal rotation in male and female swimmers as compared with the reference group. External rotation was reduced in female swimmers as compared with the female references. The same result was observed in male swimmers, but only at the age of 12 years.

Clinical consequence:Competitive swimming in children seems to lead to a decreased range of motion with regard to shoulder rotation. However, the reason for this is still unclear and further investigations are needed.
The influence of intermittent altitude exposure to 4100 m on exercise capacity and blood variables
Authors: Lundby C. , Nielsen T. K. , Dela F. , Damsgaard R.
Published: May 2005

This study was performed to investigate the effects of intermittent hypoxic exposure on blood and exercise parameters. Eight sea level residents were exposed to 2 h daily stimulus to 4100 m altitude in a hypobaric chamber for a total of 14 days. Exercise performance was evaluated at sea level before and after the hypoxic stimulation. Blood samples were obtained before, during, and at time points up to 14 days after the hypoxic exposure. No changes were observed in haemoglobin, haematocrit, reticulocytes, serum transferrin receptors, or EPO levels in the blood. Submaximal cycle (150 W) ergometer exercise corresponded to a oxygen uptake of 1.9±0.1 and 1.9±0.1 L min−1 before and after the intermittent altitude exposure, respectively. At maximal exercise the workloads attained were 343±17 and 354±27 W before and after the exposure, with corresponding oxygen uptakes of 4.0±0.2 and 4.2±0.2 L min−1. It is concluded that intermittent hypoxic exposure to 4100 m altitude for 2 h daily and a total of 14 days does not affect exercise capacity.
Post‐exercise palpation of pulse rates: its applicability to habitual exercisers
Authors: DeVan Allison E. , Lacy Barbara K. , Cortez‐Cooper Miriam Y. , Tanaka Hirofumi
Published: May 2005

Despite the increased popularity of heart rate (HR) monitors, endurance‐trained adults as well as habitual exercisers often use pulse rate palpation to periodically monitor exercise intensity. However, due to the rapid recovery of HR following exercise bouts, post‐exercise palpation of pulse rates may underestimate exercise HR. To test this hypothesis, we studied 20 young physically active adults performing two sets of exercise for 5 min at 70% and 85% of maximal HR on the treadmill; one with carotid and another with radial pulse count. Post‐exercise palpation of pulse rate was lower (P<0.01) than the actual HR during exercise, underestimating exercise HR by 20–27 bpm (beats per min). Even when ECG tracings of HR were analyzed immediately after exercise (0–15 s), a significant underestimation of exercise HR (7–9 bpm) still persisted (P<0.05). Following exercise, pulse rate obtained by carotid palpation at both intensities and radial palpation at the lower intensity was no different from the corresponding HR measured with ECG. In the radial artery trial at the higher exercise intensity, pulse rate following exercise was lower (10 bpm; P<0.05) than ECG‐derived HR. Arterial stiffness, which is closely associated with arterial baroreflex sensitivity, was not significantly related to the changes in HR with carotid palpation. We concluded that post‐exercise pulse palpations may not be appropriate as an indicator of exercise intensity in habitual exercisers.
Malignes Melanom – Eine Betrachtung von Studenten der Humanmedizin
Authors: Felcht Moritz , Fischer Jens Christian , Michels Martin , Weinhold Mario , Zouboulis Christos C.
Published: May 2005

Das einer steigenden Inzidenz unterliegende maligne Melanom entsteht als melanozytäre Geschwulst überwiegend auf der Haut und ist für etwa 90 % der Mortalität an bösartigen Hauttumoren verantwortlich. Als wichtigster Risikofaktor wurde noch vor dem UV‐Licht die genetische Disposition erkannt, wobei sich das Risiko durch bedachte UV‐Licht‐Exposition reduzieren läßt. Wichtige neue diagnostische Verfahren sind die Sentinel‐Lymphadenektomie und der Einsatz von Tumormarkern im Blut. Das Melanom zeichnet sich durch eine ausgeprägte Therapieresistenz aus, so daß die derzeit einzige kurative Therapie in der frühen Exzision zu sehen ist. Damit ist eine verbesserte Früherkennung essentiell. Experimentelle Therapieansätze wie die Vakzinierung mit dendritischen Zellen zeigen erste Erfolge, müssen aber in multizentrischen, randomisierten Studien noch überprüft werden.
Deutliche Einschränkung der Lebensqualität bei Patienten mit Pemphigus vulgaris: Ergebnisse der deutschen Bullous Skin Disease (BSD)‐Studiengruppe
Authors: Mayrshofer Franziska , Hertl Michael , Sinkgraven Ronald , Sticherling Michael , Pfeiffer Christiane , Zillikens Detlef , Messer Gerald , Rzany für die deutscheBSD‐Studiengruppe Berthold
Published: May 2005

Hintergrund: Pemphigus vulgaris ist eine potentiell lebensbedrohliche Autoimmunerkrankung von Schleimhäuten und Haut, die durch Antikörper gegen Adhäsionsmoleküle der Epidermis vermittelt wird. Klinisch charakteristisch sind chronische, häufig schmerzhafte Blasen beziehungsweise Erosionen der Haut und Schleimhäute. Bisher liegt jedoch noch keine Untersuchung zur Lebensqualität dieser Patienten vor.

Patienten und Methodik: Die Erfassung erfolgte im Rahmen der multizentrischen BSD (Bullous Skin Diseases)‐Studiengruppe. In den Universitätskliniken Dresden, Erlangen, Kiel, Mannheim, München und Würzburg wurden von November 1997 bis Januar 2002 insgesamt 36 Patienten mit der Erstdiagnose Pemphigus vulgaris behandelt. 30 der 36 (83 %) Patienten waren bereit, an der Befragung zu ihrer durch die Krankheit beeinträchtigten Lebensqualität teilzunehmen. Die Erfassung erfolgte mit der von A. Y. Finlay zur Verfügung gestellten deutschen Version des ‚Dermatology Life Quality Index’ (DLQI). Der DLQI kann Werte von 0 bis 30 einnehmen; ein erhöhter Wert spricht für eine eingeschränkte Lebensqualität.

Ergebnisse: Der DLQI‐Gesamtscore lag bei den untersuchten Patienten mit Pemphigus vulgaris bei 10 (± 6,7) Punkten. Dies entspricht im Vergleich zu anderen Hauterkrankungen einer sehr starken Einschränkung der Lebensqualität.

Schlußfolgerung: Der DLQI bietet sich als mögliche zusätzliche Zielgröße bei der Evaluation von Therapieerfolgen des Pemphigus vulgaris und für zukünftige kontrollierte klinische Studien dieser Erkrankung an.
Neodymium‐YAG Laser for hemangiomas and vascular malformations – long term results
Authors: Ulrich Heidi , Bäumler Wolfgang , Hohenleutner Ulrich , Landthaler Michael
Published: May 2005

Background: Hemangiomas and vascular malformations are the most common vascular lesions of infancy. Different lasers can be used for treatment. Nd:YAG laser photocoagulation is particularly effective because of its deep penetration into tissue.

Patients and methods: Thirty‐one patients, aged from three months to 18 years, with voluminous hemangiomas and venous malformations were treated with a cw‐neodymium:YAG laser. The quartz fibre was used in percutaneous and intralesional technique. Long‐term follow‐up data were acquired by clinical control or a patient questionnaire for a maximal period of eight years. Twenty patients could be evaluated.

Results: In the group with hemangiomas (n = 15), three cases showed nearly complete remission (> 90 %), ten cases had a partial reduction in size (50 – 90 %), in one case there was stable disease and in one case tumor growth. In the group with venous malformations (n = 5) two cases showed an excellent response (> 90 %), one case a moderate response (25 – 50 %) and in two cases there was no improvement. Adverse effects included scars (40 %), hyper‐ and hypopigmentation (23 %), mild atrophy (20 %) and a wrinkled texture (17 %). After maximal reduction in size, 30 % of the patients were not satisfied with the laser treatment outcome and elected surgical excision of the residual lesion.

Conclusions: The neodymium:yttrium aluminium garnet (Nd:YAG) laser with percutaneous or intralesional application technique is a valuable tool for selected patients with hemangiomas and venous malformations.
Chain initiation on type I modular polyketide synthases revealed by limited proteolysis and ion‐trap mass spectrometry
Authors: Hong Hui , Appleyard Antony N. , Siskos Alexandros P. , Garcia‐Bernardo Jose , Staunton James , Leadlay Peter F.
Published: May 2005

Limited proteolysis in combination with liquid chromatography‐ion trap mass spectrometry (LC‐MS) was used to analyze engineered or natural proteins derived from a type I modular polyketide synthase (PKS), the 6‐deoxyerythronolide B synthase (DEBS), and comprising either the first two extension modules linked to the chain‐terminating thioesterase (TE) (DEBS1‐TE); or the last two extension modules (DEBS3) or the first extension module linked to TE (diketide synthase, DKS). Functional domains were released by controlled proteolysis, and the exact boundaries of released domains were obtained through mass spectrometry and N‐terminal sequencing analysis. The acyltransferase‐acyl carrier protein required for chain initiation (ATL‐ACPL), was released as a didomain from both DEBS1‐TE and DKS, as well as the off‐loading TE as a didomain with the adjacent ACP. Mass spectrometry was used successfully to monitor in detail both the release of individual domains, and the patterns of acylation of both intact and digested DKS when either propionyl‐CoA or n‐butyryl‐CoA were used as initiation substrates. In particular, both loading domains and the ketosynthase domain of the first extension module (KS1) were directly observed to be simultaneously primed. The widely available and simple MS methodology used here offers a convenient approach to the proteolytic mapping of PKS multienzymes and to the direct monitoring of enzyme‐bound intermediates.
Differential expression of endogenous sialidases of human monocytes during cellular differentiation into macrophages
Authors: Stamatos Nicholas M. , Liang Feng , Nan Xinli , Landry Karine , Cross Alan S. , Wang Lai‐Xi , Pshezhetsky Alexey V.
Published: May 2005

Sialidases are enzymes that influence cellular activity by removing terminal sialic acid from glycolipids and glycoproteins. Four genetically distinct sialidases have been identified in mammalian cells. In this study, we demonstrate that three of these sialidases, lysosomal Neu1 and Neu4 and plasma membrane‐associated Neu3, are expressed in human monocytes. When measured using the artificial substrate 2′‐(4‐methylumbelliferyl)‐α‐d‐N‐acetylneuraminic acid (4‐MU‐NANA), sialidase activity of monocytes increased up to 14‐fold per milligram of total protein after cells had differentiated into macrophages. In these same cells, the specific activity of other cellular proteins (e.g. β‐galactosidase, cathepsin A and alkaline phosphatase) increased only two‐ to fourfold during differentiation of monocytes. Sialidase activity measured with 4‐MU‐NANA resulted from increased expression of Neu1, as removal of Neu1 from the cell lysate by immunoprecipitation eliminated more than 99% of detectable sialidase activity. When exogenous mixed bovine gangliosides were used as substrates, there was a twofold increase in sialidase activity per milligram of total protein in monocyte‐derived macrophages in comparison to monocytes. The increased activity measured with mixed gangliosides was not affected by removal of Neu1, suggesting that the expression of a sialidase other than Neu1 was present in macrophages. The amount of Neu1 and Neu3 RNAs detected by real time RT‐PCR increased as monocytes differentiated into macrophages, whereas the amount of Neu4 RNA decreased. No RNA encoding the cytosolic sialidase (Neu2) was detected in monocytes or macrophages. Western blot analysis using specific antibodies showed that the amount of Neu1 and Neu3 proteins increased during monocyte differentiation. Thus, the differentiation of monocytes into macrophages is associated with regulation of the expression of at least three distinct cellular sialidases, with specific up‐regulation of the enzyme activity of only Neu1.
A strategy for the generation of specific human antibodies by directed evolution and phage display
Authors: Riaño‐Umbarila Lidia , Juárez‐González Victor Rivelino , Olamendi‐Portugal Timoteo , Ortíz‐León Mauricio , Possani Lourival Domingos , Becerril Baltazar
Published: May 2005

This study describes the construction of a library of single‐chain antibody fragments (scFvs) from a single human donor by individual amplification of all heavy and light variable domains (1.1 × 108 recombinants). The library was panned using the phage display technique, which allowed selection of specific scFvs (3F and C1) capable of recognizing Cn2, the major toxic component of Centruroides noxius scorpion venom. The scFv 3F was matured in vitro by three cycles of directed evolution. The use of stringent conditions in the third cycle allowed the selection of several improved clones. The best scFv obtained (6009F) was improved in terms of its affinity by 446‐fold, from 183 nm (3F) to 410 pm. This scFv 6009F was able to neutralize 2 LD50 of Cn2 toxin when a 1 : 10 molar ratio of toxin‐to‐antibody fragment was used. It was also able to neutralize 2 LD50 of the whole venom. These results pave the way for the future generation of recombinant human antivenoms.
Biogenesis of peroxisomes
Authors: Heiland Ines , Erdmann Ralf
Published: May 2005

Genetic and proteomic approaches have led to the identification of 32 proteins, collectively called peroxins, which are required for the biogenesis of peroxisomes. Some are responsible for the division and inheritance of peroxisomes; however, most peroxins have been implicated in the topogenesis of peroxisomal proteins. Peroxisomal membrane and matrix proteins are synthesized on free ribosomes in the cytosol and are imported post‐translationally into pre‐existing organelles (Lazarow PB & Fujiki Y (1985) Annu Rev Cell Biol1, 489–530 [1]). Progress has been made in the elucidation of how these proteins are targeted to the organelle. In addition, the understanding of the composition of the peroxisomal import apparatus and the order of events taking place during the cascade of peroxisomal protein import has increased significantly. However, our knowledge on the basic principles of peroxisomal membrane protein insertion or translocation of peroxisomal matrix proteins across the peroxisomal membrane is rather limited. The latter is of particular interest as the peroxisomal import machinery accommodates folded, even oligomeric, proteins, which distinguishes this apparatus from the well characterized translocons of other organelles. Furthermore, the origin of the peroxisomal membrane is still enigmatic. Recent observations suggest the existence of two classes of peroxisomal membrane proteins. Newly synthesized class I proteins are directly targeted to and inserted into the peroxisomal membrane, while class II proteins reach their final destination via the endoplasmic reticulum or a subcompartment thereof, which would be in accord with the idea that the peroxisomal membrane might be derived from the endoplasmic reticulum.
Vascular aneurysms in Behcet's disease
Authors: Safar Hussein A. , Abou‐Khamseen Sawsan , Kansou Jalal , Abubacker Shefeek , Francis Issam , Asfar Sami
Published: May 2005

Background: Vascular complications are fairly common in patients suffering from Behcet's disease. Peripheral arterial aneurysms affect nearly every artery in association with this disease. This report discusses the management of this complication in such patients.

Patients and Methods: Two young patients were referred to the Vascular Surgery Service, because of arterial aneurysms. Both patients were known to suffer from Behcet's disease and were on colchicine. Both had history of deep vein thrombosis and were on long‐term anticoagulant therapy (warfarin).Case 1:A 38‐year‐old man presented with recurrent abdominal pains which prove to be due to a saccular abdominal aortic aneurysm (AAA) of 6 cm diameter. An elective open repair of the AAA with tube Dacron graft was performed. At 1 year follow up the patient remained free of symptoms.Case 2:A 42‐year‐old man presented with a neck swelling, which was confirmed by duplex scan and magnetic resonance angiography to be a saccular aneurysm of the left internal carotid artery. Surgical excision of the aneurysm was carried out and the artery repaired with a GORE‐TEX patch.

Results: At 12–18 months follow up, both patients remained well and asymptomatic.

Conclusions: Patients suffering from Behcet's disease are liable to get arterial aneurysms. Surveillance by non‐invasive studies ensures early diagnosis and management of these uncommon complications of the disease.
Sources used by patients seeking information about peripheral vascular disease: Is the Internet relevant?
Authors: Durani Piyush , Croft Giles P. , Kent Patrick J.
Published: May 2005

Objective:  The use of the Internet as a source of information has increased dramatically over the last decade. Patient‐orientated vascular surgery websites have been highlighted as a poor overall source of information for such patients. The aim of this study was to investigate the sources of information used by a group of patients with peripheral vascular disease (PVD) and the usage of the Internet as a source by these patients.

Method:  Questionnaires were distributed to patients with PVD, attending an outpatient clinic at a tertiary centre. Patients were asked about demographic details, Internet access and ranking of their top three most frequently used sources of information.

Results:  Sixty‐one out of eighty questionnaires were completed. There were 40 males and 21 females; age range 34–90 years (mean 67 years). Forty‐four participants (72%) were from the lower socioeconomic classes four and five. Eight participants (13%) had access to the Internet, and only one of these had used the Internet to obtain information about their condition. Hospital and community doctors were the sources of information most commonly used by participants and these were also the sources of information perceived as most useful.

Conclusion:  The results indicate that access to the Internet is limited in this selected group of PVD patients, and this might be due to their age and socioeconomic class distribution. Although refining of current Internet sites will benefit future users, for this group of patients there is still no substitute for good doctor–patient communication.
An unusual presentation of a huge seroma following ventral hernia repair
Authors: Dukhno Oleg , Pinsk Ilya , Hertzano Yanco , Levy Isaac , Ovnat Amnon
Published: May 2005

Background:  Seroma is a well‐known complication of postoperative ventral hernia (POVH) repair. It occurs during the immediate postoperative period and usually resolves with or without drainage within 4–6 weeks. The case presented herein is interesting in that a huge seroma appeared 6 months postoperatively. Ten litres were evacuated in each of two consecutive hospitalisations. The final outcome was a complete recovery with no mesh infection and no residual seroma. Of interest are the diagnosis and treatment of this unusual clinical presentation of seroma after POVH repair.
HIGHER‐ORDER DIMENSIONS OF THE BIG FIVE PERSONALITY TRAITS AND THE BIG SIX VOCATIONAL INTEREST TYPES
Authors: MOUNT MICHAEL K. , BARRICK MURRAY R. , SCULLEN STEVE M. , ROUNDS JAMES
Published: May 2005

The purpose of this study was to identify higher‐order dimensions that explain the relationships among the Big 6 interest types and the Big 5 personality traits. Meta‐analyses were conducted to identify an 11 × 11 true score correlation matrix of interest and personality attributes. Cluster analysis and nonmetric multidimensional scaling were used to identify 3 dimensions that explained relations among the 11 attributes: (a) Interests versus Personality Traits; (b) Striving for Accomplishment Versus Striving for Personal Growth, and (c) Interacting with People Versus Interacting with Things. Overall, results clarified the relationships among interests and personality traits by showing that 3 rather than 2 dimensions best explain the relationships among interests and personality traits.
Biotic elicitors as a means of increasing isoflavone concentration of soybean seeds
Authors: AL‐TAWAHA A M , SEGUIN P , SMITH D L , BEAULIEU C
Published: May 2005

Soybean (Glycine max) seeds contain isoflavones that have positive impacts on human health. Four greenhouse experiments were conducted to determine if isoflavone concentration of mature soybean seeds could be increased using elicitor compounds. The effects on soybean seed isoflavone concentrations following foliar applications of two lipo‐chitooligosaccharides (LCO) [Bj V (C18:1 MeFuc) and Bj V (Ac, C16, MeFuc)], chitosan, actinomycetes spores (Streptomyces melanosporofaciens strain EF‐76) and yeast extract at different concentrations and growth stages were evaluated. Combined chitosan seed treatment and foliar applications were also evaluated. Concentrations of daidzein, genistein, glycitein, and total isoflavones were determined by HPLC. Foliar applications of LCOs, chitosan, and actinomycetes caused a marked increase in individual and total isoflavone concentration (ranging between 21% and 84%) of mature seeds when compared to untreated control plants. There were limited differences between the different concentrations and stages of application tested for chitosan and actinomycetes; however, response to LCOs was greatest at higher concentrations (i.e. 10‐6 M) when applied at the early podding stage. Compared to untreated plants, combined seed treatment and foliar applications of chitosan increased individual and total isoflavone concentration of mature soybean seeds by 16% to 93%. Trends were similar for different cultivars, however, the magnitude of the response varied. Finally, response to foliar applications of yeast extract was highly concentration dependent with increases of up to 56% in total isoflavone observed with 2 mg mL‐1. Results indicate that elicitors hold promise as a way of increasing isoflavone concentration of mature soybean seeds.
Survival and recovery of Phytophthora capsici and oomycetes in tailwater and soil from vegetable fields in Florida
Authors: ROBERTS P D , URS R R , FRENCH‐MONAR R D , HOFFINE M S , SEIJO T E , McGOVERN R J
Published: May 2005

A current trend in Florida agriculture to conserve water is to irrigate with surface runoff water (tailwater) recovered in retention ponds and canals. Water filtration and lemon leaf baiting recovered Phytophthora capsici and other plant pathogenic Oomycetes in runoff water from ponds and canals. A total of 196 isolates of Phytophthora spp. and 471 isolates of Pythium spp. were recovered. Phytophthora spp. included P. capsici, P. cinnamomi, P. lateralis, P. nicotianae, P. citricola, P. cryptogea and P. erythroseptica. Species of Pythium were P. aphanidermatum, P. catenulatum, P. helicoides, P. irregulare, P. myriotylum, and Pythium‘group F’. Isolates of P. aphanidermatum, P. irregulare, P. myriotylum, and Pythium‘group F’ were pathogenic on pepper and tomato. Recovery of P. capsici propagules was related to soil moisture‐holding capacity and time interval but not temperature. Recovery of P. capsici propagules at 100% soil moisture‐holding capacity and 30° C was 57 days. In tailwater, recovery of propagules of P. capsici was 63 days at 24°C to 25°C. The potential exists to reintroduce and disseminate species of Phytophthora and Pythium when using tailwater for irrigation or other practices.
Performance of sampling strategies in the presence of known spatial patterns
Authors: ALEXANDER COLIN J , HOLLAND JOHN M , WINDER LINTON , WOOLLEY CHRIS , PERRY JOE N
Published: May 2005

In crop protection and ecology accurate and precise estimates of insect populations are required for many purposes. The spatial pattern of the organism sampled, in relation to the sampling scheme adopted, affects the difference between the actual and estimated population density, the bias, and the variability of that estimate, the precision. Field monitoring schemes usually adopt time‐efficient sampling regimes involving contiguous units rather than the most efficient for estimation, the completely random sample. This paper uses spatially‐explicit ecological field data on aphids and beetles to compare common sampling regimes. The random sample was the most accurate method and often the most precise; of the contiguous schemes the line transect was superior to more compact arrangements such as a square block. Bias depended on the relationship between the size and shape of the group of units comprising the sample and the dominant cluster size underlying the spatial pattern. Existing knowledge of spatial pattern to inform the choice of sampling scheme may provide considerable improvements in accuracy. It is recommended to use line transects longer than the grain of the spatial pattern, where grain is defined as the average dimension of clusters over both patches and gaps, and with length at least twice the dominant cluster size.
A New Class of Synthetic Jet Actuators—Part I: Design, Fabrication and Bench Top Characterization
Authors: Gilarranz J. L. , Traub L. W. , Rediniotis O. K.
Published: May 2005

Although the potential of synthetic jets as flow separation control actuators has been demonstrated in the existing literature, there is a large gap between the synthetic jet actuators (SJA) used in laboratory demonstrations and the SJAs needed in realistic, full-scale applications, in terms of compactness, weight, efficiency, control authority and power density. In most cases, the SJAs used in demonstrations are either too large or too weak for realistic applications. In this work, we present the development of a new class of high-power synthetic jet actuators for realistic flow control applications. The operating principle of the actuator is the same as that of crankshaft driven piston engines, which makes a significant part of the technology necessary for the actuator development available off-the-shelf. The design of the actuator is modular and scalable. Several “building block” units can be stacked in series to create the actuator of the desired size. Moreover, active exit slot reconfiguration, in the form of variable exit slot width, decouples the actuator frequency from the actuator jet momentum coefficient and allows the user to set the two independently (within limits). Part I of this paper presents the design, fabrication and bench top characterization of the actuator. Several versions of the actuator were designed, built and tested, leading up to the development of a six-piston compact actuator that has a maximum power consumption of 1200 W (1.6 hp) and can produce (for the tested conditions) peak exit velocities as high as 124 m/s. In Part II, the actuator was housed in the interior of a NACA0015 profiled wing with a chord of 0.375 m (14.75 inches). The assembly’s performance in controlling flow separation was studied in the wind tunnel.
Structural Damage Classification Using Extreme Value Statistics
Authors: Sohn Hoon , Allen David W. , Worden Keith , Farrar Charles R.
Published: May 2005

The first and most important objective of any damage identification algorithm is to ascertain with confidence if damage is present or not. Many methods have been proposed for damage detection based on ideas of novelty detection founded in pattern recognition and multivariate statistics. The philosophy of novelty detection is simple. Features are first extracted from a baseline system to be monitored, and subsequent data are then compared to see if the new features are outliers, which significantly depart from the rest of population. In damage diagnosis problems, the assumption is that outliers are generated from a damaged condition of the monitored system. This damage classification necessitates the establishment of a decision boundary. Choosing this threshold value is often based on the assumption that the parent distribution of data is Gaussian in nature. While the problem of novelty detection focuses attention on the outlier or extreme values of the data, i.e., those points in the tails of the distribution, the threshold selection using the normality assumption weights the central population of data. Therefore, this normality assumption might impose potentially misleading behavior on damage classification, and is likely to lead the damage diagnosis astray. In this paper, extreme value statistics is integrated with the novelty detection to specifically model the tails of the distribution of interest. Finally, the proposed technique is demonstrated on simulated numerical data and time series data measured from an eight degree-of-freedom spring-mass system.
Identification of a Model Helicopter’s Yaw Dynamics
Authors: Haosheng Chen , Darong Chen
Published: May 2005

To identify the micro helicopter’s yaw dynamics, the system identification method is used and is proved to be suitable according to the validation results. In order to strengthen the information of the dynamics and reduce the effect of the noise when processing the experiment data, the conventional system identification method is modified and a weighted criterion is investigated to estimate the model parameters. In calculating the factors of the weighted criterion, a perceptron is trained to allocate the factors automatically. The model validation result shows that the model derived by this kind of method can fit the measured outputs well. The modified system identification method would be useful in identifying dynamic systems which use the multiexperiment data.
Zero Phase Learning Control Using Reversed Time Input Runs
Authors: Ye Yongqiang , Wang Danwei
Published: May 2005

Phase lead is introduced to iterative learning control systems. The best phase lead is the one that can exactly compensate the phase lag of a system. A zero phase learning control using reversed time input runs is proposed based on the analysis in frequency domain utilizing a simple phase lead generation method. The plant itself or a nominal model is used to obtain the desired phase lead to ensure the monotonic convergence of tracking errors. The learning controller is robust to large inaccuracies of system models.
Study of “Sticking and Restarting Phenomenon” in Electropneumatic Positioning Systems
Authors: Brun Xavier , Sesmat Sylvie , Thomasset Daniel , Scavarda Serge
Published: May 2005

This paper explains the possible occurrence of the “sticking and restarting phenomenon” observed with electropneumatic positioning systems. This is carried out from the notion of partial equilibrium, with the analysis of the model which incorporates two parallel phenomena which are used to generate a pressure force subjected to dry friction forces. Also, an experimental result has been studied in a particular pressure force plane which shows the origin of the problem more explicitly. The theoretical results give a necessary and sufficient condition for the restarting phenomenon not to occur and, if this condition is not validated, there is an estimation of the restarting time. Understanding this undesirable phenomenon will be the basis for further work which will attempt to find solutions to avoid its occurrence.
Design Optimization of Vehicle Structures for Crashworthiness Using Equivalent Mechanism Approximations
Authors: Hamza Karim , Saitou Kazuhiro
Published: May 2005

A new method for crashworthiness optimization of vehicle structures is presented, where an early design exploration is done by the optimization of an “equivalent” mechanism approximating a vehicle structure. An equivalent mechanism is a network of rigid links with lumped mass connected by prismatic and revolute joints with nonlinear springs approximating aggregated behaviors of structural members. A number of finite element (FE) models of the thin-walled beams with typical cross sections and wall thicknesses are analyzed to build a surrogate model that maps a property of nonlinear spring to the corresponding FE model. Using the surrogate model, an equivalent mechanism is optimized for given design objectives by selecting the properties of the nonlinear springs among the values that can be realized by an FE model. After the optimization, the component FE models corresponding to the optimal spring properties are “assembled” into a FE model of an entire structure, which is further modified for final tuning. Two case studies of a vehicle front substructure are presented, which demonstrate the approach can help obtain a better design with far less computational resources than the direct optimization of a FE model.
An Update on M- and K-Circle Theory for Planar Dyads and Triads
Authors: Mlinar John R. , Erdman Arthur G.
Published: May 2005

M and K circles are solution loci for three design positions of a dyad when one design angle is varied. This paper updates M- and K-circle theory through a geometric explanation of why regions without solutions, known as forbidden regions, exist for the case of path generation with prescribed timing and not for the case of motion generation. The extension of M-K circle theory to the linear solution of triads is also presented. This work presents the finding of circular solution curves for the linear solution of triads along with the conditions for forbidden regions.