bluuebunny/crossref_metadata_2025 huggingface dataset:
Frontal Sinus Cranialization Using the Pericranial Flap: An Added Layer of Protection
Authors: Donath Alexander , Sindwani Raj
Published: September 2006

Objectives: Extensive fractures involving the anterior and posterior tables of the frontal sinus are treated by frontal sinus cranialization. During this procedure, the disrupted posterior wall of the frontal sinus is removed, the sinus mucosa is drilled away, and the brain and dura are permitted to rest against the repaired anterior wall and sinus floor. Conventionally, the area originally occupied by the frontal sinus is left as dead space or filled with free adipose tissue. We describe a method of cranialization using a pericranial flap and report our experience with this technique.

Study Design: Retrospective study.

Methods: The medical records of patients who underwent frontal sinus cranialization using the pericranial flap at our institution were reviewed. Demographics, indications for cranialization, complications, and perioperative outcomes were examined.

Results: A total of 19 patients underwent (bilateral) frontal sinus cranialization with the pericranial flap between 2000 and 2005. Indications included extensive frontal sinus fractures involving the posterior table (78.9%), mucocele (10.5%), arteriovenous malformation (5.3%), and frontal bone osteomyelitis (5.3%). There were no intraoperative complications. A postoperative cerebrospinal fluid leak occurred in one patient with extensive skull base injuries. This was repaired endoscopically. Follow‐up ranged from 9 to 55 months.

Conclusions: The pericranial flap is easily harvested and versatile. Using this vascularized tissue during cranialization affords added protection by providing an extra barrier between the intracranial cavity and the frontal bone and sinonasal tract. This technique is inexpensive, safe, and effective and should be considered when cranialization of the frontal sinus is performed.
Quality of Life in Advanced Oropharyngeal Carcinoma After Chemoradiation Versus Surgery and Radiation
Authors: Mowry Sarah E. , Ho Allen , LoTempio Maria M. , Sadeghi Ahmad , Blackwell Keith E. , Wang Marilene B.
Published: September 2006

Objective: The objective of this cohort study from a tertiary academic university practice was to identify differences in patients' perceived quality of life after either chemoradiation or surgery and radiation for advanced‐stage oropharyngeal carcinoma.

Methods: From institutional databases, thirty‐five patients were identified who had undergone either primary chemoradiation or primary surgery and postoperative radiation for advanced oropharyngeal cancer (stage II‐IV). Patients voluntarily responded by mail using the University of Washington quality‐of‐life instrument version 4 (UW‐QOL). Data were analyzed using χ2 and Wilcoxon tests.

Results: There were 17 patients who underwent chemoradiation and 18 patients who underwent surgery and postoperative radiation. All surgical patients had undergone free‐flap reconstruction. Patients completed the UW‐QOL an average of 25 months after treatment. There was no statistically significant difference between the two groups with regard to any specific domain, including pain, appearance, swallowing, chewing, speech, saliva, or mood. There was a trend toward significance for taste (P = .07) with chemoradiation patients reporting poorer taste function. The lack of difference in the patients' perception of appearance and swallowing was rather surprising given the vastly different treatment modalities. Respondents reported equivalent overall quality of life in response to global quality‐of‐life questions.

Conclusion: Most patients with advanced oropharyngeal carcinoma report good quality of life after treatment, regardless of treatment modality. Although the short‐term side effects of treatment may be different between the groups, long‐term quality of life is remarkably similar whether the patients choose primary chemoradiation or surgery with postoperative radiation.
Immediate Recurrent Laryngeal Nerve Reconstruction and Vocal Outcome
Authors: Yumoto Eiji , Sanuki Tetsuji , Kumai Yoshihiko
Published: September 2006

Objective: The objective of this prospective study was to assess the long‐term effects of immediate reconstruction of the recurrent laryngeal nerve (RLN) during thyroid cancer extirpation on postoperative phonatory function.

Subjects and Methods: The subjects were 22 patients with advanced thyroid cancer who underwent resection of the primary lesion and involved RLN. RLN paralysis was seen in 12 patients preoperatively and involvement of the RLN was noted intraoperatively in 10. Immediate reconstruction of the RLN was performed on eight patients using the great auricular nerve and one underwent direct anastomosis of the RLN stumps (group I). Nine patients opted not to have phonosurgical procedures (group II). The remaining four had arytenoid adduction immediately after cancer extirpation (group III). Phonatory function (stroboscopy, maximum phonation time [MPT], mean airflow rate [MFR], harmonics‐to‐noise ratio [HNR], jitter, and shimmer) was followed for at least 9 months.

Results: Minimal or no glottal gap during phonation was observed in six patients in group I, whereas the patients in group II had a large gap along the entire fold. HNR, MPT, and MFR were significantly better in group I (17.7 ± 3.6 dB, 15.1 ± 6.3 s, and 100 ± 32 mL/s, respectively) than in group II (12.1 ± 2.9 dB, 5.4 ± 3.1 s, and 430 ± 207 mL/s, respectively). Patients in group III had a gap of varying degrees along the membranous fold. Although HNR, shimmer, and MPT in group III were comparable to group I, the other parameters were less f/vorable than in group I.

Conclusion: Immediate RLN reconstruction at the time of thyroid cancer extirpation can provide excellent postoperative phonatory function.
Surgical Treatment of Pediatric Cholesteatomas
Authors: Shirazi Mobeen A. , Muzaffar Kamil , Leonetti John P. , Marzo Sam
Published: September 2006

Objective: Management of pediatric cholesteatomas remains controversial. We reviewed our 16‐year experience in the surgical treatment of cholesteatomas in children and describe a treatment paradigm.

Study Design: The authors conducted a retrospective review.

Methods: A total of 106 mastoidectomies (86 for an acquired cholesteatoma and 20 for a congenital cholesteatoma) were performed in children 16 years old and younger from 1988 to 2003. Follow up ranged from 2 years to 12 years with a mean follow‐up period of 6 years. Hearing outcomes, cholesteatoma recidivism, and dry mastoid cavity were the main outcomes measured.

Results: Seven (7%) patients had revision surgery for cholesteatoma recidivism. Rates of cholesteatoma recurrence for canal all up (CWU) and canal wall down (CWD) mastoidectomy groups were similar (8% vs. 6%). The percentage of patient with good serviceable hearing (pure‐tone average ≤25 dB) was higher in those with a CWU mastoidectomy as compared with the CWD mastoidectomy group (81% vs. 47%) (P < .05). Extent of disease and stapes superstructure erosion on presentation were significant (P < .05) predictors of both cholesteatoma recidivism and poor hearing. All 106 subjects studied had a dry mastoid and 78 patients (74%) had a maintenance‐free cavity at the time the study was completed.

Conclusion: The treatment of pediatric cholesteatomas should be individualized with CWD mastoidectomy chosen for patients with recurrent or more extensive disease. We conclude that the CWU procedure is an adequate surgical option for treating most acquired and congenital cholesteatomas, preventing disease recurrence, and maintaining good hearing outcomes.
Reconstruction of Dorsal and/or Caudal Nasal Septum Deformities With Septal Battens or by Septal Replacement: An Overview and Comparison of Techniques
Authors: André Robert F. , Vuyk Hadé D.
Published: September 2006

Objectives: The objectives of this study were to describe and compare two techniques used to correct nasal septum deviations located in the dorsal and/or caudal septum.

Study Design: The authors conducted a retrospective clinical chart review.

Methods: The authors conducted a comparison of functional and technical results between surgery in the L‐strut of the septum in 114 patients with septal battens or by septal replacement by subjective self‐evaluation and by examination of the position of the septum during follow up.

Results: There was subjective improvement in nasal breathing in 86% of the septal batten group and in 94% of the septal replacement group. This difference was not statistically significant. The technical result was judged by examining the position of the septum during follow up as midline, slightly deviated, or severely deviated. The septum was significantly more often located in the midline during follow up in the septal replacement group than in the septal batten group.

Conclusion: Treatment of deformities located in the structurally important L‐strut of the septum may be technically challenging and many functional, structural, and esthetic considerations must be taken into account. On the basis of this series, both septal battens and septal replacement techniques may be considered for correction of deviations in this area. The functional improvement rates were not significantly different between the techniques, although during follow up, the septum appeared to be significantly more often located in the midline in the septal replacement group. The techniques are described and their respective advantages and potential drawbacks are discussed.
Development and Validation of the Vocal Tremor Scoring System
Authors: Bové Michiel , Daamen Nicole , Rosen Clark , Wang Chen‐Chi , Sulica Lucian , Gartner‐Schmidt Jackie
Published: September 2006

Background: Essential tremor (ET) occurs in approximately 4% of the population, and 25% of patients with ET have vocal tract involvement referred to as essential tremor of voice (ETV). Treatment of vocal tremor has a variable success rate most likely as a result of inaccurate identification of the affected area(s). A vocal tremor assessment system was developed to standardize the evaluation and scaling of vocal tremor. Applying this system clinically can help determine who will benefit most from botulinum toxin injection treatment. The Vocal Tremor Scoring System (VTSS) can also be used as a tool to determine treatment efficiency for all treatment modalities of ETV, including surgery, medications, and implantable devices.

Study Design: The authors studied instrument development and validation.

Methods: A clinical consensus conference was conducted to develop an assessment tool for standardized rating of vocal tremor location and severity. The assessment tool was then tested for reliability using video‐perceptual analysis. Once validated, the assessment tool was applied to 10 examinations of patients with vocal tremor who had been treated with botulinum toxin A (BtxA) injections of the thyroarytenoid muscle(s) to determine the ability of the scoring instrument to predict treatment outcome.

Results: The VTSS is based on severity scores for different anatomic sites within the vocal tract. The assessment areas of the VTSS are the palate, base of tongue, pharyngeal walls, larynx, supraglottis, and true vocal cords. Statistical analysis of the video‐perceptual analysis results showed that the anatomic sites with the best interrater agreement were the true vocal folds, palate, base of tongue, and supraglottis. Overall, the VTSS demonstrated a level of interrater reliability of at least 0.914 at all sites. Intrarater reliability was excellent. The consensus group also analyzed 10 standardized examinations and the scores from both reviewer groups were then compared and found to have a reliability of at least 0.6 at each site. Pretreatment VTSS scores of 10 patients with ETV who underwent BtxA therapy were then compared with treatment response. The VTSS predicted the favorable treatment outcome 100% of the time when the score given to the true vocal folds was equal or greater to the mean of the scores given to the other sites.

Conclusion: The VTSS represents the first standardized system for rating anatomic site(s) and severity of vocal tremor. This tool will allow improved communication between otolaryngologists, facilitate research in vocal tremor treatments, and establish a descriptive system for assessing vocal tremor. Using this assessment tool for patients with vocal tremor increases optimal patient selection and success rate for intralaryngeal botulinum toxin treatment.
The Endoscopic Management of Zenker Diverticulum: CO2 Laser versus Endoscopic Stapling
Authors: Miller Frank R. , Bartley Jess , Otto Randal A.
Published: September 2006

Objective: The purpose of this project was to analyze the endoscopic management of Zenker diverticulum (ZD) using both the CO2 laser and endoscopic stapling techniques. This study compares the two techniques in terms of diverticulum size, onset to oral intake, hospital stay, resolution of symptoms (dysphagia and regurgitation), and complications.

Study Design: A retrospective consecutive case series was performed at an academic medical center.

Methods: Forty patients underwent an attempted endoscopic resection of the ZD using either the CO2 laser or the endoscopic stapling technique. The two techniques were compared on a variety of parameters, including diverticulum size, hospital stay, onset to oral intake, resolution of symptoms, and complications. Symptom scores were obtained before and after surgery with a patient self‐reported scoring report (scale 0–3 for both dysphagia and regurgitation with 0 indicating asymptomatic and 3 severe symptoms).

Results: Forty patients underwent an attempted endoscopic management of ZD. Five patients (12.5%) failed endoscopic exposure (four converted to open, one observed). Sixteen patients underwent CO2 laser management and 19 underwent endoscopic stapling. The mean diverticulum size (3.8 cm CO2 laser versus 4.4 cm stapling) was not significantly different for the two groups. Both groups demonstrated a significant decrease in preoperative versus postoperative dysphagia and regurgitation symptoms scores, respectively, CO2 laser dysphagia scores decreasing from 2.75 to 1.38 and the regurgitation score dropping from 1.51 to 0.68, whereas endoscopic stapling dysphagia score decreased from 2.74 to 1.21 and the regurgitation score dropped from 1.37 to 0.53. Overall, 86% of patients demonstrated an onset of liquid intake on postoperative day 1 and the average length of stay was 3.4 days in the CO2 laser group and 1.5 days in the endoscopic stapling (P < .0015). Complications included dental trauma in four patients (two CO2 laser and two stapling) and subcutaneous air in three patients (all three CO2 laser). There were no cases of mediastinitis, recurrent laryngeal nerve injury, fistula, or perioperative death.

Conclusions: The endoscopic management of ZD is a safe and effective technique. The endoscopic stapling technique appears to have an improved efficacy and safety when compared with the CO2 laser technique. The two techniques are compared and contrasted.
How Can an Underlaid Fascia Graft Form the Middle Layer of a Reconstructed Tympanic Membrane?
Authors: Szabó László Z.
Published: September 2006

Objective/Hypothesis: Autogenous f/scia is a material popularly applied as a connective tissue graft for reconstruction of the tympanic membrane. The objective was to establish how an underlaid fascia graft can form the middle layer of a reconstructed tympanic membrane.

Study design: In the underlaid technique, the graft is laid on the medial surface of the tympanic remnant without removal of the mucous membrane, which is covered with entodermal epithelium. Interestingly earlier authors have regarded this fact as natural, though, if it is really so, it must be a result of an unexpected, special mechanism that apparently contradicts the general rules of transplantation.

Methods: Experimental operations were performed on one ear of 114 adult, male guinea pigs. The posterior quadrants of the tympanic membrane were removed, and the perforation was closed with an underlaid temporal fascia graft. Examinations were made after different survival times. The temporal bones were removed immediately, and specimens were processed histologically.

Results: The graft proved to be well adapted to the margin of the tympanic membrane. The epithelium of the outer surface grew both from the meatal skin and from the margin of the tympanic remnant. In connection with the regeneration of the mucous membrane of the inner surface, unexpected, special events were observed. The originally intact epithelium of the mucous membrane was annihilated, and disappeared completely. Consequently, the fibrous layer of the tympanic remnant and the graft came into direct contact and grew together. The regeneration of the mucous membrane started at the margin of the graft.

Conclusions: The histologic observations described have clarified the problem of the underlaid technique.
Use of Intradermal Dilutional Testing and Skin Prick Testing: Clinical Relevance and Cost Efficiency
Authors: Seshul Merritt , Pillsbury Harold , Eby Thomas
Published: September 2006

Objectives/Hypothesis: The objective was to determine the agreement of the positive results from a multiple skin prick test (SPT) device with the ability to determine a definable endpoint through intradermal dilutional testing (IDT) to compare semiquantitatively the degree of positivity of SPT results with quantitative results from IDT and to analyze the cost of immunotherapy based on SPT compared with IDT guided by SPT.

Study Design: Retrospective review of clinical data (random accrual).

Methods: One hundred thirty‐four patients underwent allergy screening using a multiple SPT device. Antigens testing positive by skin prick device were tested using IDT on a separate day. Antigens testing negative by SPT were not evaluated by IDT. Regional allergy testing practice patterns were determined, and a cost analysis using Medicare rates was performed

Results: There was good agreement between an antigen testing positive by SPT and the determination of a definable endpoint (93.33%, n = 1,334 antigens). The degree of positivity from the SPT correlated poorly with the final endpoint concentration (r = 0.40, P < .0001). Blended testing techniques were similar in cost when compared with several commonly used allergy testing protocols.

Conclusions: Antigens which show reactivity to a multiple SPT device usually have a treatable endpoint that is independent of the degree of positivity of the SPT result. IDT is an important step in the determination of the strongest starting dose of immunotherapy that may be safely administered. Initiating immunotherapy in this manner may potentially create significant health care savings by shortening the time required for a patient to reach their individual maximally tolerated dose. The use of a relatively large screening panel is cost effective and does not increase the average number of antigens treated by immunotherapy. Blended allergy testing techniques that include IDT in their protocol are comparable in cost with commonly used allergy testing protocols.
Interplay between Ino80 and Swr1 chromatin remodeling enzymes regulates cell cycle checkpoint adaptationin response to DNA damage
Authors: Papamichos-Chronakis Manolis , Krebs Jocelyn E. , Peterson Craig L.
Published: September 2006

Ino80 and Swr1 are ATP-dependent chromatin remodeling enzymes that have been implicated in DNA repair. Here we show that Ino80 is required for cell cycle checkpoint adaptation in response to a persistent DNA double-strand break (DSB). The failure of cells lacking Ino80 to escape checkpoint arrest correlates with an inability to maintain high levels of histone H2AX phosphorylation and an increased incorporation of the Htz1p histone variant into chromatin surrounding the DSB. Inactivation of Swr1 eliminates this DNA damage-induced Htz1p incorporation and restores H2AX phosphorylation and checkpoint adaptation. We propose that Ino80 and Swr1 function antagonistically at chromatin surrounding a DSB, and that they regulate the incorporation of different histone H2A variants that can either promote or block cell cycle checkpoint adaptation.
Proteolysis of MLL family proteins is essential for Taspase1-orchestrated cell cycle progression
Authors: Takeda Shugaku , Chen David Y. , Westergard Todd D. , Fisher Jill K. , Rubens Jeffrey A. , Sasagawa Satoru , Kan Jason T. , Korsmeyer Stanley J. , Cheng Emily H.-Y. , Hsieh James J.-D.
Published: September 2006

Taspase1 was identified as the threonine endopeptidase that cleaves mixed-lineage leukemia (MLL) for proper Hox gene expression in vitro. To investigate its functions in vivo, we generated Taspase1−/− mice. Taspase1 deficiency results in noncleavage (nc) of MLL and MLL2 and homeotic transformations. Remarkably, our in vivo studies uncover an unexpected role of Taspase1 in the cell cycle. Taspase1−/− animals are smaller in size. Taspase1−/− mouse embryonic fibroblasts (MEFs) exhibit impaired proliferation, and acute deletion of Taspase1 leads to a marked reduction of thymocytes. Taspase1 deficiency incurs down-regulation of Cyclin Es, As, and Bs and up-regulation of p16Ink4a. We show that MLL and MLL2 directly target E2Fs for Cyclin expression. The uncleaved precursor MLL displays a reduced histone H3 methyl transferase activity in vitro. Accordingly, chromatin immunoprecipitation assays demonstrate a markedly decreased histone H3 K4 trimethylation at Cyclin E1 and E2 genes in Taspase1−/− cells. Furthermore, MLLnc/nc;2nc/nc MEFs are also impaired in proliferation. Our data are consistent with a model in which precursor MLLs, activated by Taspase1, target to Cyclins through E2Fs to methylate histone H3 at K4, leading to activation. Lastly, Taspase1−/− cells are resistant to oncogenic transformation, and Taspase1 is overexpressed in many cancer cell lines. Thus, Taspase1 may serve as a target for cancer therapeutics.
Crystal structure of SV40 large T-antigen bound to p53: interplay between a viral oncoprotein and a cellular tumor suppressor
Authors: Lilyestrom Wayne , Klein Michael G. , Zhang Rongguang , Joachimiak Andrzej , Chen Xiaojiang S.
Published: September 2006

The transformation potential of Simian Virus 40 depends on the activities of large T-antigen (LTag), which interacts with several cellular tumor suppressors including the important “guardian” of the genome, p53. Inhibition of p53 function by LTag is necessary for both efficient viral replication and cellular transformation. We determined the crystal structure of LTag in complex with p53. The structure reveals an unexpected hexameric complex of LTag binding six p53 monomers. Structure-guided mutagenesis of LTag and p53 residues supported the p53–LTag interface defined by the complex structure. The structure also shows that LTag binding induces dramatic conformational changes at the DNA-binding area of p53, which is achieved partially through an unusual “methionine switch” within p53. In the complex structure, LTag occupies the whole p53 DNA-binding surface and likely interferes with formation of a functional p53 tetramer. In addition, we showed that p53 inhibited LTag helicase function through direct complex formation.
Modulating the outer membrane with small RNAs
Authors: Guillier Maude , Gottesman Susan , Storz Gisela
Published: September 2006

MicF, one of the first chromosomally encoded regulatory small RNAs (sRNAs) to be discovered, was found to modulate the expression of OmpF, an abundant outer membrane protein. Several recent papers have now shown that this is not an isolated case. At least five other sRNAs also regulate the synthesis of outer membrane porins, and additional sRNAs modulate the expression of other outer membrane proteins. Here we review what is known about these sRNAs and discuss the implications of this regulation.
Targeted ablation of ILK from the murine heart results in dilated cardiomyopathy and spontaneous heart failure
Authors: White Donald E. , Coutu Pierre , Shi Yan-Fen , Tardif Jean-Claude , Nattel Stanley , St. Arnaud René , Dedhar Shoukat , Muller William J.
Published: September 2006

A requirement for integrin-mediated adhesion in cardiac physiology is revealed through targeted deletion of inte-grin-associated genes in the murine heart. Here we show that targeted ablation of the integrin-linked kinase (ILK) expression results in spontaneous cardiomyopathy and heart failure by 6 wk of age. Deletion of ILK results in disaggregation of cardiomyocytes, associated with disruption of adhesion signaling through the β1-inte-grin/FAK (focal adhesion kinase) complex. Importantly, the loss of ILK is accompanied by a reduction in cardiac Akt phosphorylation, which normally provides a protective response against stress. Together, these results suggest that ILK plays a central role in protecting the mammalian heart against cardiomyopathy and failure.
S. pombe CLASP needs dynein, not EB1 or CLIP170, to induce microtubule instability and slows polymerization rates at cell tips in a dynein-dependent manner
Authors: Grallert Agnes , Beuter Christoph , Craven Rachel A. , Bagley Steve , Wilks Deepti , Fleig Ursula , Hagan Iain M.
Published: September 2006

The Schizosaccharomyces pombe CLIP170-associated protein (CLASP) Peg1 was identified in a screen for mutants with spindle formation defects and a screen for molecules that antagonized EB1 function. The conditional peg1.1 mutant enabled us to identify key features of Peg1 function. First, Peg1 was required to form a spindle and astral microtubules, yet destabilized interphase microtubules. Second, Peg1 was required to slow the polymerization rate of interphase microtubules that establish end-on contact with the cortex at cell tips. Third, Peg1 antagonized the action of S. pombe CLIP170 (Tip1) and EB1 (Mal3). Fourth, although Peg1 resembled higher eukaryotic CLASPs by physically associating with both Mal3 and Tip1, neither Tip1 nor Mal3 was required for Peg1 to destabilize interphase microtubules or for it to associate with microtubules. Conversely, neither Mal3 nor Tip1 required Peg1 to associate with microtubules or cell tips. Consistently, while mal3.Δ and tip1.Δ disrupted linear growth, corrupting peg1+ did not. Fifth, peg1.1 phenotypes resembled those arising from deletion of the single heavy or both light chains of fission yeast dynein. Furthermore, all interphase phenotypes arising from peg1+ manipulation relied on dynein function. Thus, the impact of S. pombe CLASP on interphase microtubule behavior is more closely aligned to dynein than EB1 or CLIP170.
The Zinc-finger factor Insm1 (IA-1) is essential for the development of pancreatic β cells and intestinal endocrine cells
Authors: Gierl Mathias S. , Karoulias Nikolaos , Wende Hagen , Strehle Michael , Birchmeier Carmen
Published: September 2006

The pancreatic and intestinal primordia contain epithelial progenitor cells that generate many cell types. During development, specific programs of gene expression restrict the developmental potential of such progenitors and promote their differentiation. The Insm1 (insulinoma-associated 1, IA-1) gene encodes a Zinc-finger factor that was discovered in an insulinoma cDNA library. We show that pancreatic and intestinal endocrine cells express Insm1 and require Insm1 for their development. In the pancreas of Insm1 mutant mice, endocrine precursors are formed, but only few insulin-positive β cells are generated. Instead, endocrine precursor cells accumulate that express none of the pancreatic hormones. A similar change is observed in the development of intestine, where endocrine precursor cells are formed but do not differentiate correctly. A hallmark of endocrine cell differentiation is the accumulation of proteins that participate in secretion and vesicle transport, and we find many of the corresponding genes to be down-regulated in Insm1 mutant mice. Insm1 thus controls a gene expression program that comprises hormones and proteins of the secretory machinery. Our genetic analysis has revealed a key role of Insm1 in differentiation of pancreatic and intestinal endocrine cells.
A novel genetic hierarchy functions during hypaxial myogenesis: Pax3 directly activates Myf5 in muscle progenitor cells in the limb
Authors: Bajard Lola , Relaix Frédéric , Lagha Mounia , Rocancourt Didier , Daubas Philippe , Buckingham Margaret E.
Published: September 2006

We address the molecular control of myogenesis in progenitor cells derived from the hypaxial somite. Null mutations in Pax3, a key regulator of skeletal muscle formation, lead to cell death in this domain. We have developed a novel allele of Pax3 encoding a Pax3–engrailed fusion protein that acts as a transcriptional repressor. Heterozygote mouse embryos have an attenuated mutant phenotype, with partial conservation of the hypaxial somite and its myogenic derivatives, including some hindlimb muscles. At these sites, expression of Myf5 is compromised, showing that Pax3 acts genetically upstream of this myogenic determination gene. We have characterized a 145-base-pair (bp) regulatory element, at −57.5 kb from Myf5, that directs transgene expression to the mature somite, notably to myogenic cells of the hypaxial domain that form ventral trunk and limb muscles. A Pax3 consensus site in this sequence binds Pax3 in vitro and in vivo. Multimers of the 145-bp sequence direct transgene expression to sites of Pax3 function, and an assay of its activity in the chick embryo shows Pax3 dependence. Mutation of the Pax3 site abolishes all expression controlled by the 145-bp sequence in transgenic mouse embryos. We conclude that Pax3 directly regulates Myf5 in the hypaxial somite and its derivatives.
SyMAP: A system for discovering and viewing syntenic regions of FPC maps
Authors: Soderlund Carol , Nelson William , Shoemaker Austin , Paterson Andrew
Published: September 2006

Previous approaches to comparing gene and chromosome organization between two genomes have been based on genetic maps or genomic sequences. We have developed a system to align an FPC-based physical map to a genomic sequence based on BAC end sequences and sequence-tagged hybridization markers and to align two FPC maps to one another based on shared markers and fingerprints. The system, called SyMAP (Synteny Mapping and Analysis Program), consists of an algorithm to compute synteny blocks and Web-based graphics to visualize the results. The approach to calculating the anchors (corresponding elements on the respective maps) maximizes the inclusion of anchors with different rates of divergence. Chains (putative syntenic sets of anchors) are computed using a dynamic programming algorithm, which includes off-diagonal anchors that result from map coordinate errors and small inversions. As the gap parameters (the distances allowed between anchors in a chain) can vary over different data sets and be difficult to set manually, they are automatically computed per data set. The criterion for a chain to be acceptable is based on the number of anchors and the Pearson correlation coefficient. Neighboring chains are merged into synteny blocks for display. This algorithm has been tested with three data sets that vary in the number of BACs, BAC end sequences, hybridization markers, distance between anchors, and number and antiquity of genome duplication events. The Web-based graphics uses Java for a highly interactive display that allows the user to interrogate the evidence of synteny.
Evidence for biogeographic patterning of mitochondrial DNA sequences in Eastern horse populations
Authors: McGahern A. , Bower M. A. M. , Edwards C. J. , Brophy P. O. , Sulimova G. , Zakharov I. , Vizuete‐Forster M. , Levine M. , Li S. , MacHugh D. E. , Hill E. W.
Published: September 2006

Equine mitochondrial DNA (mtDNA) phylogeny reconstruction reveals a complex pattern of variation unlike that seen in other large domesticates. It is likely that this pattern reflects a process of multiple and repeated, although not necessarily independent, domestication events. Until now, no clear geographic affiliation of clades has been apparent. In this study, amova analyses have revealed a significant non‐random distribution of the diversity among equine populations when seven newly sequenced Eurasian populations were examined in the context of previously published sequences. The association of Eastern mtDNA types in haplogroup F was highly significant using Fisher's exact test of independence (P = 0.00000). For the first time, clear biogeographic partitioning has been detected in equine mtDNA sequence.
Opportunistic predation and offspring sex ratios of cicada‐killer wasps (Sphecius speciosus Drury)
Authors: GRANT PETER R.
Published: August 2006

Abstract 1. The way in which hunting of prey affects the sex ratio of the predator’s offspring is not well understood. Female cicada‐killer wasps are convenient for study because they specialise in capturing cicadas to provision their offspring. Cicada prey are nearly twice as heavy as the wasps that carry them, hence some degree of prey selectivity by the wasps is to be expected. It has been suggested that wasps bias their offspring towards females by foraging selectively for female prey, whereas there is some evidence that sex ratios are actually male‐biased. This study was designed to establish the connection between foraging and offspring sex ratio.

2. Three, non‐exclusive, hypotheses of selective predation were tested. The frequency of predation on different classes of prey in conjunction with their availability was estimated by intercepting the wasps on their way to their nests and by sampling cicadas in the environment. The hypothesis of selective predation was not supported; predation appears to be opportunistic and non‐selective. Cicada prey weight was not a simple linear function of wasp weight, although the smallest wasps were constrained to carry small prey.

3. Wasp offspring (larvae) were excavated from subterranean nests and found to be male‐biased (3 : 1 or 4 : 1) in 2 years. The observed ratios are close to expectation from Fisher’s equal‐investment model, taking account of sexual size dimorphism, and are evidently unrelated to the sex of the prey. A simple binomial probability rule of sex allocation provides a behavioural mechanism for producing the observed sex ratio of offspring.
Relationships between distribution and abundance vary with spatial scale and ecological group in stream bryophytes
Authors: HEINO JANI , VIRTANEN RISTO
Published: September 2006

1. We examined whether the local abundance of stream bryophytes in a boreal drainage basin (Koutajoki system in northeastern Finland) correlated with their: (i) regional occupancy; (ii) provincial distribution in northwestern Europe; and (iii) global range size. We specifically tested whether aquatic and semi‐aquatic species differ in their distribution–abundance relationships. We also analysed the frequency distributions of occupancy at two spatial scales: within the focal drainage system and across provinces of northwestern Europe.

2. Regional occupancy and mean local abundance of stream bryophytes were positively correlated, and the relationship was rather strong in aquatic species but very weak in semi‐aquatic species. Local abundance was related neither to provincial distribution nor global distribution.

3. Species frequency distributions differed between regional occupancy and provincial distribution. While most species were rare with regard to their regional occupancy within the focal drainage system, most of the same set of species were common and occurred in most provinces in northwestern Europe.

4. The results indicate the presence of dominants (core species) and transients/subordinates (satellite species) among stream bryophytes, highlighting marked differentiation in life‐history strategies and growth form. The observed abundance–occupancy relationships suggest that dispersal limitation and metapopulation processes may govern the dynamics of obligatory aquatic stream bryophytes. In semi‐aquatic species, however, habitat availability may be more important in contributing to regional occupancy.
Indirect food web interactions increase growth of an algivorous stream fish
Authors: HARGRAVE CHAD W. , RAMIREZ RAUL , BROOKS MELODY , EGGLETON MICHAEL A. , SUTHERLAND KATHERINE , DEATON RAELYNN , GALBRAITH HEATHER
Published: September 2006

1. We tested the hypothesis that indirect food web interactions between some common, invertivorous fishes and their prey would positively affect growth of an algivorous fish species. Specifically, we predicted that orangethroat darter (Etheostoma spectabile) would increase periphyton biomass via a top‐down pathway, indirectly enhancing growth of the algivorous central stoneroller minnow (Campostoma anomalum). Moreover, we predicted that sand shiner (Notropis stramineus) would increase periphyton biomass via a bottom‐up pathway and indirectly enhance growth of the stoneroller minnow.

2. In an 83‐day experiment in large, outdoor, stream mesocosms, we stocked two fish species per mesocosm (stoneroller and either darter or shiner), estimated the effects of the invertivorous and grazing fishes on periphyton biomass and estimated growth of the algivorous fish.

3. The darter consumed grazing invertebrates, indirectly increasing periphyton biomass. The shiner consumed terrestrial insects as predicted, but it did not affect periphyton biomass.

4. In support of our hypothesis, the darter indirectly enhanced stoneroller growth. As predicted, stonerollers consumed the increased periphyton in streams with darters, resulting in greater growth, condition and gut fullness compared to streams without darters. No indirect interaction was observed between stonerollers and shiners.

5. Our study suggests that some invertivorous fish species can positively affect growth of algivorous fishes through indirect food web interactions. Thus, in stream communities, it is possible that the loss of a single, invertivorous fish taxon could have negative consequences on algivorous fish populations via the removal of positive indirect food web interactions.
Inhibition of development of anti‐predator morphology in the small cladoceran Bosmina by an insecticide: impact of an anthropogenic chemical on prey–predator interactions
Authors: SAKAMOTO MASAKI , CHANG KWANG‐HYEON , HANAZATO TAKAYUKI
Published: September 2006

1. The combined effect of the insecticide carbaryl and the predator (Leptodora kindtii) kairomone was assessed on the development of protuberant morphology in the small cladoceran Bosmina fatalis, a feature which evolved originally as a response to the kairomone. The experiment showed that Bosmina changed its morphology in response to the kairomone, but development was inhibited by carbaryl at a sub‐lethal concentration even in the presence of the kairomone. At the same time, reduction of fecundity was observed in animals exposed to carbaryl.

2. A short‐term feeding experiment (B. fatalis versus Leptodora) indicated that such low concentrations of the insecticide had no impact on predation by Leptodora. Thus, it is suggested that the inhibition of development of anti‐predatory defences in Bosmina can increase its vulnerability to predation.

3. Such disturbance of chemical communication by the insecticide reduces the individual survival rate of prey Bosmina in the environment with high predator density. On the other hand, reduction of fecundity may result in decreased population growth rate of animals.

4. The impact of the insecticide on the anti‐predator morphology in Bosmina (inhibition) was opposite to that in Daphnia (enhancement). This suggests that biochemical induction processes in the development of anti‐predatory morphology are evolutionally different between Daphnia and Bosmina.
Ichthyophonus‐induced cardiac damage: a mechanism for reduced swimming stamina in salmonids
Authors: Kocan R , LaPatra S , Gregg J , Winton J , Hershberger P
Published: September 2006

Swimming stamina, measured as time‐to‐fatigue, was reduced by approximately two‐thirds in rainbow trout experimentally infected with Ichthyophonus. Intensity of Ichthyophonus infection was most severe in cardiac muscle but multiple organs were infected to a lesser extent. The mean heart weight of infected fish was 40% greater than that of uninfected fish, the result of parasite biomass, infiltration of immune cells and fibrotic (granuloma) tissue surrounding the parasite. Diminished swimming stamina is hypothesized to be due to cardiac failure resulting from the combination of parasite‐damaged heart muscle and low myocardial oxygen supply during sustained aerobic exercise. Loss of stamina in Ichthyophonus‐infected salmonids could explain the poor performance previously reported for wild Chinook and sockeye salmon stocks during their spawning migration.
Myocardial glycogen storage disease in farmed rainbow trout, Oncorhynchus mykiss (Walbaum)
Authors: Tørud B , Taksdal T , Dale O B , Kvellestad A , Poppe T T
Published: September 2006

This paper is the first description of a spontaneous glycogen‐storage disease in a lower vertebrate, as previous descriptions deal with humans and other mammals, or fish where the condition has been experimentally induced. Affected farmed rainbow trout experienced increased mortality from 60 days post‐startfeeding and displayed clinical signs of heart failure with abnormal behaviour, exophthalmia, distended abdomen and ventral skin petechiation. Necropsy revealed alterations in cardiac shape with distended atria and rounded ventricles. Microscopically, the compact wall of the ventricle was absent, uneven or thinner than normal. The cardiac myocytes contained extensive amounts of glycogen in cytoplasmic vacuoles as demonstrated by periodic acid‐Schiff staining that was abolished by saliva‐diastase pretreatment on serial sections. Associated lesions included conspicuous subepicardial and myocardial vascularization, epicardial thickening and necrosis of the ventricular compactum/spongiosum interphase. The lesions in cardiac myocytes had a striking resemblance to glycogenosis type II (Pompe disease), a rare autosomal recessive lysosomal storage disease in humans. This condition was more severe and mortality was higher in a replicate/parallel fish group treated perorally with 17α‐methyltestosterone to produce all‐female progeny, indicating that the hormone treatment aggravated the condition resulting in earlier and more severe manifestation of the disease in this group.
Characterization of Edwardsiella tarda strains isolated from turbot, Psetta maxima (L.)
Authors: Castro N , Toranzo A E , Barja J L , Núñez S , Magariños B
Published: September 2006

The biochemical, serological and molecular characteristics of a group of 21 Edwardsiella tarda strains isolated from turbot, Psetta maxima, in two different areas of Europe were analysed and compared with a total of 13 strains of this bacterial species with different geographical and host origins. All the turbot isolates were biochemically identical to the E. tarda strains included as reference. The use of different techniques including microagglutination, dot blot and Western blot of lipopolysaccharides allowed us to determine that all the turbot isolates constitute an homogeneous and distinctive serological group. Genetic analysis by randomly amplified polymorphic DNA (RAPD) analysis demonstrated that although the E. tarda strains from turbot were compiled in a unique group using the primers P3 and P6, two clonal lineages could be detected when oligonucleotides P4 and P5 were employed.
WS09 Biosensor‐based Methods: the instrumental link between biology and physics
Authors: ELLIOTT C. T. , BERGWERFF A. A
Published: August 2006

Objective

Tremendous progress has been made in the ability to measure particular contaminants or veterinary drugs at very low concentrations. However, rare or previously unknown compounds, metabolites and mixtures are still presenting considerable analytical challenges, while this category in particular might be relevant in terms of food safety. In addition, the need for higher throughput screening strategies at lower costs also demands for methods in addition to chemical analysis. There is considerable development in methodology based on the interaction with bio‐macromolecules or living cells or on a biological response in the exposed animal. The aim of this workshop is to provide an up‐o‐date and practical overview of the various analytical and biological strategies that are available to screen or detect (prior) exposure to drugs, contaminants and pollutants.
B7‐H1 expression is upregulated in peripheral blood CD14+ monocytes of patients with chronic hepatitis B virus infection, which correlates with higher serum IL‐10 levels
Authors: Geng L. , Jiang G. , Fang Y. , Dong S. , Xie H. , Chen Y. , Shen M. , Zheng S.
Published: September 2006

Summary.  Chronicity in hepatitis B virus (HBV) infection is maintained by increased type 2 T‐helper cell response, possibly because of increased interleukin‐10 (IL‐10) productions. B7‐H1 can negatively regulate T‐cell responses via its receptor, programmed death 1. Ligation of B7‐H1 to T‐cells can result in the preferential secretion of IL‐10. In this study, we investigated whether there was an upregulated expression of B7‐H1 in peripheral blood mononuclear cells in patients chronically infected by HBV and further explored the correlation between B7‐H1 expression and serum interleukin 2, interferon‐γ, IL‐10, HBeAg, alanine aminotransferase (ALT) levels and viral load. Fifty‐five patients with chronic HBV infection and 20 healthy controls (HCs) were enrolled in the present study. The results showed that in patients with chronic hepatitis B CD14+ monocytes but not CD3+ and CD19+ cells had a significantly increased expression of B7‐H1 compared with HCs, which positively correlates with serum IL‐10 levels and the presence of HBeAg and negatively correlates with serum ALT levels. In conclusion, chronic HBV patients harbour an increased B7‐H1 expression in CD14+ monocytes compared with controls, which may be responsible for the increased serum IL‐10 levels. This might be an important way by which HBV evades an adequate immune response, leading to viral persistence and disease chronicity.
Circulating levels of brain‐derived neurotrophic factor correlate with disease severity in the intrinsic type of atopic dermatitis
Authors: Raap U. , Werfel T. , Goltz C. , Deneka N. , Langer K. , Bruder M. , Kapp A. , Schmid‐Ott G. , Wedi B.
Published: September 2006

Background:  Recent studies have shed light on the complex regulation of genetic, environmental, immunologic and pharmacologic factors, which contribute to the development of atopic dermatitis (AD). However, it is still unclear to which extent neuroimmune mediators have a role in AD.

Aims of the study:  To assess peripheral neurotrophin levels and their correlation with scoring atopic dermatitis (SCORAD) scores in both the intrinsic and extrinsic types of AD compared with patients with psoriasis and nonatopic healthy subjects.

Methods:  Levels of brain‐derived neurotrophic factor (BDNF) and nerve growth factor (NGF) were assessed in peripheral blood with enzyme‐linked immunosorbent assay. Based on IgE‐mediated sensitization, AD was divided into the extrinsic and intrinsic type. Severity of AD was assessed with SCORAD score and with psoriasis area and severity index (PASI) in patients with psoriasis.

Results:  Brain‐derived neurotrophic factor and NGF were detectable in all the subjects studied. However, the levels of both neurotrophins were significantly higher in patients with extrinsic and intrinsic types of AD compared with patients with psoriasis and nonatopic healthy subjects (NGF: P < 0.001, BDNF: P < 0.001). NGF and BDNF levels were similar in the intrinsic and extrinsic type of AD. There was a significant correlation between BDNF and SCORAD score only in patients with the intrinsic type of AD (r = 0.57, P < 0.05).

Conclusions:  This study shows for the first time that NGF and BDNF are increased in both, the extrinsic type and the intrinsic type of AD. This finding points to a similar pathophysiologic background implicating a neuroimmune network in both variants of this chronic inflammatory skin disease. Future studies are needed to show the direct mechanisms of neurotrophin action in chronic inflammatory skin.