bluuebunny/crossref_metadata_2025 huggingface dataset:
Bcr‐Abl‐induced tyrosine phosphorylation of Emi1 to stabilize Skp2 protein via inhibition of ubiquitination in chronic myeloid leukemia cells
Authors: Chen Jing‐Yi , Wang Ming‐Chung , Hung Wen‐Chun
Published: August 2010

Our previous study demonstrates that Bcr‐Abl fusion oncogene frequently found in chronic myeloid leukemia (CML) cells can up‐regulate Skp2 expression via transcriptional activation. However, Bcr‐Abl also modulates Skp2 protein stability in these cells. Treatment of Bcr‐Abl kinase inhibitor imatinib led to G1 growth arrest accompanied with reduced Skp2 expression. Interestingly, reduction of Skp2 protein occurred prior to down‐regulation of Skp2 mRNA suggesting a post‐translational control. The half‐life of Skp2 protein was significantly attenuated in imatinib‐treated cells. These effects are not cell line specific because similar results were also found in CML cells obtained from patients. Knockdown of Bcr‐Abl similarly caused Skp2 protein instability. The decrease of Skp2 was induced by increased protein degradation through the ubiquitin/proteasome pathway. Imatinib treatment or Bcr‐Abl knockdown reduced Emi1, an endogenous inhibitor of the E3 ligase APC/Cdh1 which mediated Skp2 degradation. We found that Emi1 stability was regulated by phosphorylation and mutation of tyrosine 142 reduced the stability. Our data suggested Bcr‐Abl‐induced Emi1 phosphorylation might be mediated by Src kinase. Firstly, Src inhibitor SU6656 inhibited Emi1 tyrosine phosphorylation in K562 cells. Secondly, transfection of v‐Src rescued the reduction of Emi1 by imatinib. Thirdly, mutation of tyrosine 142 to phenylalanine (Y142F) abolished the phosphorylation of Emi1 by recombinant Src kinase. In addition, ectopic expression of wild type but not Y142F mutant Emi1 counteracted imatinib‐caused growth arrest. Collectively, our results suggest that Bcr‐Abl increases Emi1 phosphorylation and stability to prevent Skp2 protein degradation via APC/Cdh1‐induced ubiquitination and to enhance proliferation of CML cells. J. Cell. Physiol. 226: 407–413, 2011. © 2010 Wiley‐Liss, Inc.
Altered intracellular calcium fluxes in pancreatic cancer induced diabetes mellitus: Relevance of the S100A8 N‐terminal peptide (NT‐S100A8)
Authors: Basso Daniela , Greco Eliana , Padoan Andrea , Fogar Paola , Scorzeto Michele , Fadi Elisa , Bozzato Dania , Moz Stefania , Navaglia Filippo , Zambon Carlo‐Federico , Seraglia Roberta , De Carlo Eugenio , Valerio Anna , Reggiani Carlo , Pedrazzoli Sergio , Plebani Mario
Published: August 2010

After isolating NT‐S100A8 from pancreatic cancer (PC) tissue of diabetic patients, we verified whether this peptide alters PC cell growth and invasion and/or insulin release and [Ca2+]i oscillations of insulin secreting cells and/or insulin signaling. BxPC3, Capan1, MiaPaCa2, Panc1 (PC cell lines) cell growth, and invasion were assessed in the absence or presence of 50, 200, and 500 nM NT‐S100A8. In NT‐S100A8 stimulated β‐TC6 (insulinoma cell line) culture medium, insulin and [Ca2+] were measured at 2, 3, 5, 10, 15, 30, and 60 min, and [Ca2+]i oscillations were monitored (epifluorescence) for 3 min. Five hundred nanomolars NT‐S100A8 stimulated BxPC3 cell growth only and dose dependently reduced MiaPaCa2 and Panc1 invasion. Five hundred nanomolars NT‐S100A8 induced a rapid insulin release and enhanced β‐TC6 [Ca2+]i oscillations after both one (F = 6.05, P < 0.01) and 2 min (F = 7.42, P < 0.01). In the presence of NT‐S100A8, [Ca2+] in β‐TC6 culture medium significantly decreased with respect to control cells (F = 6.3, P < 0.01). NT‐S100A8 did not counteract insulin induced phosphorylation of the insulin receptor, Akt and IκB‐α, but it independently activated Akt and NF‐κB signaling in PC cells. In conclusion, NT‐S100A8 exerts a mild effect on PC cell growth, while it reduces PC cell invasion, possibly by Akt and NF‐κB signaling, NT‐S100A8 enhances [Ca2+]i oscillations and insulin release, probably by inducing Ca2+ influx from the extracellular space, but it does not interfere with insulin signaling. J. Cell. Physiol. 226: 456–468, 2011. © 2010 Wiley‐Liss, Inc.
Physiological implications of adenosine receptor‐mediated platelet aggregation
Authors: Johnston‐Cox Hillary A. , Yang Dan , Ravid Katya
Published: August 2010

Adenosine is an important mediator of inhibition of platelet activation. This metabolite is released from various cells, as well as generated via activity of ecto‐enzymes on the cell surface. Binding of adenosine to A2subtypes (A2Aor A2B), G‐protein coupled adenosine receptors, results in increased levels of intracellular cyclic adenosine monophosphate (cAMP), a strong inhibitor of platelet activation. The role and importance of adenosine and its receptors in platelet physiology are addressed in this review, including recently identified roles for the A2Badenosine receptor as a modulator of platelet activation through its newly described role in the control of expression of adenosine diphosphate (ADP) receptors. J. Cell. Physiol. 226: 46–51, 2010. © 2010 Wiley‐Liss, Inc.
Forced activation of Stat5 subjects mammary epithelial cells to DNA damage and preferential induction of the cellular response mechanism during proliferation
Authors: Eilon Tali , Barash Itamar
Published: August 2010

Parity‐dependent adenocarcinoma tumors developed in postestropausal transgenic mice expressing a constitutively active Stat5 variant (STAT5ca) in their mammary gland. These tumors maintained elevated expression levels of genes regulating the cellular DNA damage response (DDR) mechanism, compared to the intact gland. No correlation with STAT5ca expression was observed for these genes in the established tumors. However, activated Stat5a in individual cells of the rarely and earlier developed hyperplasia was associated with induced Chk2 activity. Deregulated Stat5 may already cause DNA damage during the fertile period. This hypothesis and the specific vulnerable stage were further studied in mammary epithelial cells that were stably transfected with β‐lactoglobulin (BLG)/STAT5ca and exposed to a reproduced reproductive cycle. During the pregnancy‐like proliferative state, STAT5ca expression was induced by the added lactogenic hormones. Production of reactive oxygen species, rather than proliferation, served as the primary mediator of DNA damage and cellular DDR. Differentiated cells expressed higher levels of STAT5ca and retained the DNA nicks. However, the elevated expression of the genes involved in DDR was downregulated. Higher levels of DNA damage were also detected in the mammary gland of transgenic mice expressing the BLG/STAT5ca during pregnancy and lactation. However, the relative number of damaged cells was much lower than that in the reproduced in vitro stages and the insults were generally associated with apoptosis and DDR. This study implicates pregnancy as the vulnerable stage for deregulated Stat5 activity, and demonstrates that DNA insults in viable differentiated mammary epithelial cells are ignored by the DDR mechanism. J. Cell. Physiol. 226: 616–626, 2011. © 2010 Wiley‐Liss, Inc.
Exceptional structural and mechanical flexibility of the nuclear pore complex
Authors: Liashkovich Ivan , Meyring Anne , Kramer Armin , Shahin Victor
Published: August 2010

Nuclear pore complexes (NPCs) mediate all transport between the cytosol and the nucleus and therefore take centre stage in physiology. While transport through NPCs has been extensively investigated little is known about their structural and barley anything about their mechanical flexibility. Structural and mechanical flexibility of NPCs, however, are presumably of key importance. Like the cell and the cell nucleus, NPCs themselves are regularly exposed to physiological mechanical forces. Besides, NPCs reveal striking transport properties which are likely to require fairly high structural flexibility. The NPC transports up to 1,000 molecules per second through a physically 9 nm wide channel which repeatedly opens to accommodate macromolecules significantly larger than its physical diameter. We hypothesised that NPCs possess remarkable structural and mechanical stability. Here, we tested this hypothesis at the single NPC level using the nano‐imaging and probing approach atomic force microscopy (AFM). AFM presents the NPC as a highly flexible structure. The NPC channel dilates by striking 35% on exposure to trans‐cyclohexane‐1,2‐diol (TCHD), which is known to transiently collapse the hydrophobic phase in the NPC channel like receptor–cargo complexes do in transit. It constricts again to its initial size after TCHD removal. AFM‐based nano‐indentation measurements show that the 50 nm long NPC basket can astonishingly be squeezed completely into the NPC channel on exposure to incremental mechanical loads but recovers its original vertical position within the nuclear envelope plane when relieved. We conclude that the NPC possesses exceptional structural and mechanical flexibility which is important to fulfilling its functions. J. Cell. Physiol. 226: 675–682, 2011. © 2010 Wiley‐Liss, Inc.
Decrease in claudin‐2 expression enhances cell migration in renal epithelial madin–darby canine kidney cells
Authors: Ikari Akira , Takiguchi Ayumi , Atomi Kosuke , Sato Tomonari , Sugatani Junko
Published: August 2010

Migration of renal epithelial cells increases after renal tubular damage, but its mechanism has not been clarified in detail. Hyperosmotic stress increased a cellular injury concomitant with a decrease in mRNA and protein expression of claudin‐2 in renal tubular epithelial Madin–Darby canine kidney cells. We hypothesized that claudin‐2 is involved in the regulation of cell migration. To knockdown claudin‐2 expression, we made the cells expressing doxycycline‐inducible claudin‐2 shRNA vector. Claudin‐2 knockdown affected neither the endogenous expression levels of claudin‐1, ‐3, ‐4, and ‐7 nor the Triton X‐100 solubility of these claudins. Transepithelial electrical resistance was increased by claudin‐2 knockdown without affecting permeability to FITC‐dextran (4,000 Da). BrdU incorporation assay and cell counting revealed that cell proliferation and viability are unaffected by claudin‐2 knockdown. In the wound‐healing assay, the recovery rate of wound area was increased by claudin‐2 knockdown. The mRNA expression and activity of matrix metalloproteinase‐9 (MMP‐9) were increased by claudin‐2 knockdown. A selective MMP‐9 inhibitor suppressed cell migration in the claudin‐2 knockdown cells. Hyperosmotic stress increased the expression and activity of MMP‐9, which were inhibited by claudin‐2 overexpression. These results suggest that the decrease in claudin‐2 expression enhances cell migration mediated by the increase in the expression and activity of MMP‐9. J. Cell. Physiol. 226: 1471–1478, 2011. © 2010 Wiley‐Liss, Inc.
Development of microfluidic devices for biomedical and clinical application
Authors: Webster Abigail , Greenman John , Haswell Stephen J.
Published: August 2010

This review focuses on the development and use of microfluidic devices within a clinical setting. The underlying theoretical background of microfluidics is briefly elucidated. The materials and techniques used to fabricate the devices and their applicability to the clinical environment are described. The current research in this area is appraised and projections for future applications are discussed. Copyright © 2010 Society of Chemical Industry
Piscine aquaporins: an overview of recent advances
Authors: Cerdà Joan , Finn Roderick Nigel
Published: August 2010

Aquaporins are a superfamily of integral membrane proteins that facilitate the rapid and yet highly selective flux of water and other small solutes across biological membranes. Since their discovery, they have been documented throughout the living biota, with the majority of research focusing on mammals and plants. Here, we review available data for piscine aquaporins, including Agnatha (jawless fish), Chondrichthyes (chimaeras, sharks, and rays), Dipnoi (lungfishes), and Teleostei (ray‐finned bony fishes). Recent evidence suggests that the aquaporin superfamily has specifically expanded in the chordate lineage consequent to serial rounds of whole genome duplication, with teleost genomes harboring the largest number of paralogs. The selective retention and dichotomous clustering of most duplicated paralogs in Teleostei, with differential tissue expression profiles, implies that novel or specialized physiological functions may have evolved in this clade. The recently proposed new nomenclature of the piscine aquaporin superfamily is discussed in relation to the phylogenetic signal and genomic synteny, with the teleost aquaporin‐8 paralogs used as a case study to illustrate disparities between the underlying codons, molecular phylogeny, and physical locus. Structural data indicate that piscine aquaporins display similar channel restriction residues found in the tetrapod counterparts, and hence their functional properties seem to be conserved. However, emerging evidence suggests that regulation of aquaporin function in teleosts may have diverged in some cases. Cell localization and experimental studies imply that the physiological roles of piscine aquaporins extend at least to osmoregulation, reproduction, and early development, although in most cases their specific functions remain to be elucidated.J. Exp. Zool. 313A:623–650, 2010. © 2010 Wiley‐Liss, Inc.
Ross Granville Harrison (1870–1959) and perspectives on regeneration
Authors: Maienschein Jane
Published: August 2010

Historical case studies can serve as cautionary tales, reminding us to reflect on underlying assumptions and on limitations of any particular approach. Ross Harrison's work recorded at the beginning and end of his career in the Journal of Experimental Zoology reveal his own morphological and experimental convictions, as they played out in his studies of regeneration. A closer look at this particular example of Harrison's contributions offers a perspective from which to view current studies of regenerative phenomena and assumptions about appropriate research approaches and the driving questions involved. J. Exp. Zool. (Mol. Dev. Evol.) 314B:607–615, 2010. © 2010 Wiley‐Liss, Inc.
Implementation of a hospitalist‐run observation unit and impact on length of stay (LOS): A brief report
Authors: Leykum Luci K. , Huerta Vincent , Mortensen Eric
Published: August 2010

BACKGROUND:

While the impact of hospitalists on length of stay (LOS) for inpatient medicine services has been studied, there has been little work on the impact of hospitalist involvement in short‐stay or observation units.

OBJECTIVE:

The primary objective was to examine the impact of a hospitalist‐run observation unit on LOS. The secondary objective was to assess utilization of the unit through examining case‐weight and LOS.

DESIGN:

Retrospective cohort study with a preimplementation/postimplementation analysis.

SETTING:

University Hospital, the 604‐bed teaching hospital for Bexar County, San Antonio, Texas.

PATIENTS:

All patients discharged from the inpatient medicine and observation units with diagnoses of chest pain, asthma, syncope, cellulitis, and pyelonephritis.

INTERVENTION:

Creation of a hospitalist‐run, nonteaching, 10‐bed “Clinical Decision Unit” (CDU).

MEASUREMENTS:

The overall LOS of the “top 5” most common diagnoses was compared for the 12 months preimplementation and postimplementation of the unit.

RESULTS:

The overall LOS for all patients decreased from 2.4 to 2.2 days (P = 0.05) between the 12 months preimplementation and postimplementation. The greatest decreases were seen for cellulitis (2.4‐1.9 days; P < 0.001) and asthma (2.2‐1.2 days; P < 0.001).

CONCLUSIONS:

Implementation of a hospitalist‐run observation unit was associated with a significantly decreased LOS for all patients regardless of location, suggesting that the unit has led to more efficient care. Journal of Hospital Medicine 2010; © 2010 Society of Hospital Medicine.
Quality and financial outcomes from gainsharing for inpatient admissions: A three‐year experience
Authors: Leitman I. Michael , Levin Ruth , Lipp Michael J. , Sivaprasad Latha , Karalakulasingam Christine J. , Bernard David S. , Friedmann Patricia , Shulkin David J.
Published: August 2010

BACKGROUND:

Gainsharing is a way to provide incentives to physicians to decrease hospital costs without compromising quality.

METHODS:

A pay‐for‐performance program was instituted over a three‐year period from July 2006 to June 2009. Baseline length of stay (LOS) and case costs were developed during the year prior to the inception of the program. Best practice norms (BPNs) were established at the top 25th percentile of physicians for each all patient refined (APR)‐diagnosis related group (DRG). Hospital costs were analyzed in several areas, including operating room charge (OR), supplies and implants, nursing and per‐diem room costs. Payments were based upon case level performance compared to BPN's and the physician's historic performance. Eligible cases included commercial insurance only for the first 2 years but Medicare cases were included after October 2008 resulting from a Centers for Medicare and Medicaid Services (CMS)‐approved demonstration project. Payments to physicians required meeting quality thresholds, including chart completion, and compliance with core measures.

RESULTS:

A total of 184 (54%) physicians enrolled into the program. There was a $25.1 million reduction in hospital costs during the 3 years ($16 million from participating and $9.1 million from non‐participating physicians, P < 0.01). Most cost reductions were attributed to reduced LOS and reductions in medical supply costs. Total physician payouts were over $2 million (average $1,866 per quarter). Delinquent medical records decreased from an average of 43% in the second quarter 2006 to 30% (P < 0.0001) in the second quarter 2009. Quality measures improved during the study period but not by a statistical significance.

CONCLUSIONS:

Gainsharing provided an incentive for physicians to reduce hospital costs while maintaining hospital quality. Journal of Hospital Medicine 2010. © 2010 Society of Hospital Medicine.
Advancing geriatrics education: An efficient faculty development program for academic hospitalists increases geriatric teaching
Authors: Mazotti Lindsay , Moylan Adam , Murphy Elizabeth , Harper G. Michael , Johnston C. Bree , Hauer Karen E.
Published: August 2010

BACKGROUND:

Hospitalists care for an increasing number of older patients. As teachers, they are uniquely positioned to teach geriatric skills to residents. Faculty development programs focused on geriatrics teaching skills are often expensive and time‐intensive, and may not enhance trainee learning.

OBJECTIVES:

To evaluate a train‐the‐trainer (TTT) model designed to equip hospitalists with knowledge and skills to teach geriatric topics to residents in a time‐constrained, resource‐limited environment.

DESIGN:

Cross‐sectional survey.

SETTING:

Academic tertiary hospital.

INTERVENTION:

A 10‐hour geriatric curriculum, the Reynolds Program for Advancing Geriatrics Education (PAGE), cotaught by geriatricians and hospitalists at preexisting noon conferences over 1 year that consisted of exportable teaching modules.

MEASUREMENTS:

Session leaders' and faculty participants' satisfaction, hospitalist geriatrics teaching self‐efficacy, residents' self‐report of frequency of geriatric teaching received, and frequency of geriatric skill use.

RESULTS:

The curriculum was highly rated by session leaders and hospitalist faculty. Hospitalists perceived improvement in geriatric teaching skills, indicating (1: “unlikely” to 5: “highly likely”) that they are likely to use these teaching tools in the future (M = 4.61, standard deviation [SD] = 0.53). Residents reported both significantly more geriatrics teaching by hospitalists (P < 0.05) and a borderline significant increase in their practice of geriatric clinical skills (P = 0.05).

CONCLUSIONS:

A time‐efficient geriatric faculty development program for hospitalists suggests improvement in the amount and quality of geriatrics teaching and skill practice among faculty and residents at an academic medical center. Concise faculty development programs within preexisting faculty meetings may be a feasible, successful method to increase geriatric skill development in the hospital setting. Journal of Hospital Medicine 2010; © 2010 Society of Hospital Medicine.
Gaining efficiency and satisfaction in the handoff process
Authors: Burton M. Caroline , Kashiwagi Deanne T. , Kirkland Lisa L. , Manning Dennis , Varkey Prathibha
Published: August 2010

BACKGROUND:

Handoffs, or transfers of patient care responsibility, occur frequently on hospitalist teams. The reliability and efficiency of the handoff process is a national and local concern. Most studies in the literature regard physicians‐in‐training. We studied the morning handoff process of hospitalist teams comprised of staff physicians and nurse practitioner and/or physician assistants.

METHODS:

An improvement team observed morning handoffs. Four problems were identified: unpredictable start and finish times, inefficiency, poor environment (hallway noise and distracting in‐room conversations), and poor communication. The team restructured the process and observed post‐intervention behavior at 15 and 90 days. A participant‐provider survey was conducted before and after the intervention regarding wasted time, total time‐in‐report, and satisfaction with the process.

RESULTS:

Pre‐intervention 60.5% of providers (23/38) believed morning handoff was performed in a timely fashion compared to 100% (15/15) post‐intervention (P = 0.005). Average time spent in morning report was 11 minutes, compared to 5 minutes after the intervention (P < 0.0028). Pre‐intervention 6.5 minutes were believed wasteful, compared to 0.5 minutes post‐intervention (P < 0.0001).

CONCLUSIONS:

This study identifies deficiencies in the handoff process that were addressed by enhancing the physical environment (smaller room, noise reduction, closed door), assigned seating (visual cues by table tent cards), non‐clinicians providing printed materials, standardization of written updates, team times (consistent & precise daily time for each team report), culture change including deference of attention to team receiving report with opportunity for questions, and minimization of side conversations. This intervention package resulted in an improvement in satisfaction and timeliness of clinicians involved. Journal of Hospital Medicine 2010. © 2010 Society of Hospital Medicine.
Residue content of carbaryl applied on greenhouse cucumbers and its reduction by duration of a pre‐harvest interval and post‐harvest household processing
Authors: Hassanzadeh Nasrin , Bahramifar Nader , Esmaili‐Sari Abbas
Published: August 2010

BACKGROUND: Carbaryl is widely used to control various insect pests on greenhouse cucumbers in Iran. Therefore the control of residual levels of this insecticide is highly necessary. The effects of the household processing such as washing, peeling and refrigeration storage, at 4 °C for 2 days on the reduction of residue levels in the plant tissues were investigated in the different groups. Samples were collected at 1 h to 14 days after application and analysed to determine the content and dissipation rate of carbaryl. Analysis was carried out by the QuEChERS method using HPLC‐UV.

RESULTS: Carbaryl residue in samples, which were collected post‐application in different times showed a gradual and significant (P < 0.05) decrease. The half‐life (t1/2) of carbaryl applied on cucumbers was 3.2 days. Carbaryl residues were detected in concentration ranges of 0.22–4.91 mg kg−1. Also, the results indicated that the consumable safety time of carbaryl was found to be more than 14 days on cucumber.

CONCLUSION: Household processing, such as washing and peeling and refrigeration storage, was effective in reducing the residue levels. Also, peeling was the most effective way to reduce the carbaryl residues of the cucumber samples. Washing and refrigerated storage also decreased carbaryl residues. Copyright © 2010 Society of Chemical Industry
Influence of the cultivar on the organic acid and sugar composition of potatoes
Authors: Rodríguez Galdón Beatriz , Ríos Mesa Domingo , Rodríguez Rodríguez Elena Mª , Díaz Romero Carlos
Published: August 2010

BACKGROUND: Citric, malic, tartaric, oxalic, ascorbic, aconitic and fumaric acids, and sucrose, fructose and glucose, were determined in ten potato cultivars (Azucena negra, Bonita, Bonita negra, Borralla, Colorada de baga, Mora, Negra, Palmera lagarteada, Peluca blanca and Terrenta) from the Canary Islands in order to differentiate them. The influence of the production zone was also considered.

RESULTS: Citric acid and sucrose were the most abundant organic acid and sugar, respectively. There were significant differences in all the analysed sugars and organic acids between the potato cultivars, except for oxalic and malic acids. Differences associated with the production zone were found in the contents of organic acids for some cultivars. Linear discriminant analysis is a useful tool to differentiate the potato samples according to the cultivar and the zone of production.

CONCLUSIONS: Seven organic acids (citric, oxalic, malic, tartaric, aconitic, fumaric, and ascorbic acids) were identified and quantified in potatoes. The main sugars (sucrose, glucose and fructose) were also determined. The genetic information of the cultivars determines marked differences in sugars and organic acid contents among the analysed potato cultivars. The soil and climatic conditions affect the organic acid and sugar contents of some potato cultivars. Copyright © 2010 Society of Chemical Industry
Factors affecting usefulness of triticale grain for bioethanol production
Authors: Obuchowski Wiktor , Banaszak Zofia , Makowska Agnieszka , Łuczak Miłosz
Published: August 2010

BACKGROUND: Triticale grain could be a useful material for bioethanol production. The aim of this study was to examine how grain cultivar, nitrogen fertilisation level, location and year affect the starch content in triticale grain and which method of starch determination, polarimetric, enzymatic or near‐infrared transmission (NIT), gives the best prediction of real bioethanol productivity from triticale grain.

RESULTS: It was found that the starch content in triticale grain was correlated positively with test weight and 1000‐kernel weight but negatively with falling number and protein content. All factors, i.e. cultivar, nitrogen fertilisation level, location and year, as well as the intrinsic interaction between these factors, had a significant effect on the starch level in triticale grain. The NIT procedure of starch determination gave the best results in predicting the real yield of ethanol obtained on the basis of classic fermentation (95% match), while the enzymatic and polarimetric methods corresponded with the real results at levels of 89–90 and 78–82% respectively.

CONCLUSION: Grain growth conditions related to location and nitrogen fertilisation level had the most noticeable effect on grain starch content, while grain yield per hectare had the most significant effect on ethanol productivity. Copyright © 2010 Society of Chemical Industry
Efficacy of leukotriene antagonists as concomitant therapy in allergic rhinitis
Authors: Cingi Cemal , Gunhan Kivanc , Gage‐White Linda , Unlu Halis
Published: August 2010

Objectives/Hypothesis:

The symptoms of allergic rhinitis result from an immunoglobulin E‐dependent mast cell activation cascade, marked by the release of inflammatory mediators, including histamine. Patients with perennial allergic rhinitis also have elevated levels of cysteinyl leukotrienes (CysLTs) in nasal lavage fluid. Histamine and CysLTs produce different responses in the pathogenesis of allergic rhinitis, and this study tested the hypothesis that the effects of combined antihistamine and leukotriene antagonist therapy would be more effective than antihistamine alone.

Study Design:

Multicentered, prospective, randomized, placebo‐controlled, parallel‐group.

Methods:

Three groups totaling 275 patients using: 1) fexofenadine alone, 2) fexofenadine with montelukast, or 3) fexofenadine with placebo, participated in a 21‐day trial conducted during the spring pollen season. Objective analysis included pre‐ and poststudy physical examination findings and nasal resistance measurements. Subjective data gathered included a daily patient diary and pre‐ and poststudy patient satisfaction measurements.

Results:

The group using both fexofenadine and montelukast showed significantly better control of nasal congestion both subjectively, using patient diary and visual analog scale evaluations, and objectively, using rhinomanometry and physical examination, compared to groups using antihistamine alone or with placebo.

Conclusions:

Our data provided both objective and subjective evidence that leukotriene receptor antagonist‐antihistamine combination therapy is more effective than antihistamine alone in the control of allergic rhinitis symptoms. Laryngoscope, 2010
Spontaneous cerebrospinal fluid rhinorrhea: A clinical and anatomical study
Authors: Tóth Miklós , Selivanova Oxana , Schaefer Steven , Mann Wolf
Published: August 2010

Objectives/Hypothesis:

Spontaneous nasal cerebrospinal fluid (CSF) fistula represents a rare clinical entity. The possible etiology and the localization of the rhinorrhea remain an ongoing clinical challenge. The purpose of this study was to evaluate the localization of spontaneous CSF fistula and to correlate it with anatomical studies.

Study Design:

Retrospective clinical study, prospective anatomical study.

Methods:

Twenty‐nine patients with spontaneous CSF rhinorrhea were retrospectively studied, 10 males and 19 females. Ages ranged from 10 to 92 years (mean, 50 years). In addition, 48 human skulls from newborns to adults were examined for the postnatal development of the anterior and middle cranial fossa.

Results:

In our study isolated cribriform plate defects were found in four patients. The lateral lamina of the ethmoid bone showed defects in three patients. In nine patients the bony defect could be found in the region of the fovea ethmoidalis. The bony defect between the extra‐ and intracranial space was found in the lateral recess of the sphenoid sinus in eight patients. Five patients had special sites (e.g., supraorbital recess and frontal recess).

Conclusions:

This study supports the theory that bony dehiscence in the lateral lamina of the ethmoid bone can be congenital and can also be spontaneously acquired later. The bony dehiscence in the lateral wall of the sphenoid sinus can only develop during pneumatization. Laryngoscope, 2010
The relationship between depressive symptoms and voice handicap index scores in laryngopharyngeal reflux
Authors: Elam Jackson C. , Ishman Stacey L. , Dunbar Kerry B. , Clarke John O. , Gourin Christine G.
Published: August 2010

Objectives/Hypothesis:

To determine if a relationship exists between depression and Voice Handicap Index (VHI) scores in patients with laryngopharyngeal reflux (LPR) disease.

Study Design:

Retrospective analysis of prospectively collected data.

Methods:

One hundred nineteen patients were prospectively evaluated with the VHI questionnaire and the Beck Depression Inventory Fast Screen (BDI‐FS) survey. Patients with a pre‐existing diagnosis of depression were excluded.

Results:

Complete data was available for 36 patients with LPR and 53 controls. No significant differences existed between groups with respect to age, race, or gender. Mild depressive symptoms were identified in 9% of controls and 3% of LPR patients by BDI‐FS screening (P = .4); no patients had moderate or severe depression symptoms. Compared to controls, patients with LPR had significantly higher mean scores for total VHI (16.2 vs. 6.6, P = .002), functional VHI (5.8 vs. 2.4, P = .02), and physical VHI (6.9 vs. 2.5, P = .008) domains. Mean scores for the VHI emotional domain (3.5 vs. 1.7, P = .2) and BDI‐FS (0.2 vs. 0.8, P = .3) did not differ between patients with LPR and controls. For all participants, a positive correlation was found between BDI‐FS score and VHI emotional domain score (r = 0.3, P = .008).

Conclusions:

Patients with LPR report poorer VHI functional and physical scores compared to controls; however, LPR symptoms do not result in significantly worse VHI emotional domain scores or depressive symptoms. There is a correlation between VHI emotional domain scores and BDI‐FS scores. These data suggest that LPR patients with poor VHI emotional domain scores might benefit from screening for depressive symptoms. Laryngoscope, 2010
Cyclooxygenase‐2 signaling in vocal fold fibroblasts
Authors: Branski Ryan C. , Zhou Hang , Sandulache Vlad C. , Chen Jie , Felsen Diane , Kraus Dennis H.
Published: August 2010

Objectives/Hypothesis:

Inflammation and its role in a coordinated fibroplastic response, which disrupts the structure of the vocal folds following injury, is critical. Cyclooxygenase‐2 (COX‐2) is an important enzyme involved in both inflammation and fibrosis; in addition, it is a prime target for therapeutic intervention. We sought to study this pathway in vocal fold fibroblasts to provide a foundation for future interventional studies.

Study Design:

In vitro.

Methods:

Human vocal fold fibroblasts were incubated with IL‐1β to determine the effects on COX‐2 signaling, along with upstream regulatory mechanisms and downstream mediators of wound healing. In vitro methods to assess mRNA expression, as well as intracellular and secreted protein (sodium dodecyl sulfate polyacrylamide gel electrophoresis and enzyme‐linked immunosorbent assay) were employed.

Results:

IL‐1β regulation of COX‐2 mRNA and protein levels was dose and time dependent and IL‐1β altered PGE2 metabolism, via regulation of both synthetic and degradative enzymes. IL‐1β increased nuclear factor (NF)‐κB activation and nuclear translocation. Inhibition of the p50 and p65 subunits of NF‐κB decreased IL‐1β‐induced COX‐2 transcription. IL‐1β also altered mRNA expression of four cell‐surface prostaglandin receptors.

Conclusions:

Inflammation and fibrosis are important in the vocal fold pathophysiologic response to injury. Our data suggest that COX‐2 and PGE2 are inducible in human vocal fold fibroblasts, and this response appears to be NF‐κB‐dependent. We purport this fundamental investigation will lead to increased insight regarding injury and repair in the vocal folds, with the ultimate goal of developing novel clinical care paradigms. Laryngoscope, 2010
Implementation of an efficient shooting and bouncing rays scheme
Authors: Dikmen Fatih , Ergin A.Arif , Sevgili A. Levent , Terzi Bilgin
Published: August 2010

Implementation of the shooting and bouncing rays (SBR) method for radar cross section or scattering center prediction of complex electrically large objects is studied with a focus on the computational efficiency. A triangulated CAD model is assumed and SBR is processed by a ray‐triangle intersection algorithm. An octree space partitioning, which might be based on either rectangular boxes or spheres as bounding volumes, is used to speedup the intersection decision. The effect of proper implementation and choice of the bounding volume to reduce “the constant in front” of the leading order complexity is demonstrated. It is shown that the required computer resources can be reduced drastically using the techniques outlined in this article. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2409–2413, 2010; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25492
A low‐power X‐band free electron laser by prebunching of the electrons
Authors: Malek Fareq , Lucas James , Huang Yi
Published: August 2010

We are developing a prototype free electron laser that is compact, low cost, and low power. The design, setup, and results of a novel X‐band rectangular waveguide prebunched free electron laser (PFEL) are presented in this article. Our initial device operates at 10 GHz and uses two rectangular waveguide cavities (one for velocity modulation and the other for energy extraction). The electron beam used in this experiment is produced by thermionic electron gun, which operates at 3 kV and up to 50 μA. The nominal beam diameter is 1 mm passing across the X‐band cavity resonators. The resonant cavity consists of a thin gap section of height 1.5 mm, which reduces the beam energy required for beam wave interaction. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2483–2486, 2010; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25493
Benefits of using conductive plastics in shielding configurations to reduce radiated electromagnetic interference
Authors: Lozano‐Guerrero Antonio José , Robinson Martin Paul , Díaz‐Morcillo Alejandro , Balbastre‐Tejedor Juan Vicente
Published: August 2010

Conductive plastic cabinets have become an alternative to traditional metallic enclosures to shield electronic equipment from electromagnetic interference. These materials allow a wide range of conductivities that can satisfy any particular design. In this article, the benefits of using conductive plastics in enclosure configurations have been evaluated. A design with an outer metallic layer and an inner layer of conductive dielectric can provide advantages from both materials as a conductive plastic box is lighter and its shielding properties may have advantages over metallic materials. An optimum for resonance suppression has been obtained for the hybrid structure. These shielding structures have been evaluated with the help of measurements and simulations. Shielding effectiveness andQfactor have been used to compare the capabilities of these enclosures with the metallic ones showing their benefits and possibilities. Resonance suppression and shielding levels provided by conductive plastics are discussed. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2476–2480, 2010; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25499
Wideband multibeam formation using fully spatial signal processing for indoor communications
Authors: Uthansakul Monthippa , Attakitmongkol Kitti , Bunsanit Chayanit , Uthansakul Peerapong
Published: August 2010

Recently, an outstanding wideband beamformer utilizing only space domain, not time or frequency domain, has been proposed, so‐called wideband spatial beamformer. The advantage of this beamformer is that it requires only attenuators or amplifiers to perform beam formation in wide frequency band as its weighting coefficients become real values. As a result, tapped delay lines, frequency filters, or phase shifters are avoidable. This article presents an extension work for the mentioned wideband spatial beamformer. The beamforming algorithm is modified to produce multibeam patterns with one set of real‐valued weights for the purpose of energy saving. The proposed concept is tested through simulated and measured results to confirm beamforming capability. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2423–2427, 2010; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25506
Single‐shot all‐optical sampling oscilloscope using a polarization‐maintaining resonator for pulse replication
Authors: Komanec Matěj , Honzátko Pavel , Zvánovec Stanislav
Published: August 2010

An all‐optical single‐shot sampling oscilloscope with a picosecond resolution is developed. An innovative approach for data pulse replication using a polarization‐maintaining resonator is used. Pulses are sampled in a highly nonlinear fiber. Acquired data are used for pulse shape reconstruction. Proposed setup eliminates the need of a delay line. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2452–2456, 2010; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25509
X‐band low phase noise in‐phase and out‐of‐phase injection‐locked push–push DRO
Authors: Cao Zhou , Tang Xiaohong , Wang Ling
Published: August 2010

An X‐band push–push dielectric resonator (DR) oscillator with injection locking capability has been developed.Two injection locking methods, i.e., the in‐phase method and the out‐of‐phase method, are studied. It is found that the out‐of‐phase method has wider locking range and much less effects on fundamental suppression than that of the in‐phase method. The oscillator generates an output power of 9.5 dBm at 12.4 GHz and has a fundamental suppression of 32.5 dBc. Despite using a high quality (Q) factor DR, wide locking range has been obtained. SiGe HBTs with good flicker noise performance were chosen for low phase noise design. The phase noise values of the free running oscillator are −104.4 dBc/Hz, −120.2 dBc/Hz, and −142.6 dBc/Hz at 10 kHz, 100 kHz, and 1 MHz offsets from the carrier frequency, respectively. The phase noise performance is superior or comparable to the reported designs. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2448–2452, 2010; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25510
A single‐chip RF power amplifier with integrated impedance matching Wilkinson power dividers for 5.2 GHz WLAN applications
Authors: Kaymaksut Ercan , Gürbüz Yasar , Tekin İbrahim
Published: August 2010

In this article, a new on‐chip power combining technique by using impedance matching Wilkinson power divider circuits will be presented. Two impedance matching Wilkinson power dividers are employed for matching the input and output impedances of the amplifier to 50 Ω as well as splitting the input power into two amplifiers and combining their output powers. A 5.2 GHz fully integrated class‐A mode combined power amplifier is designed in 0.35 μm SiGE BiCMOS technology to assess the power combining technique for WLAN applications. The power amplifier with the on‐chip lumped element impedance matching Wilkinson power divider circuits has a measured small signal gain of 5.21 dB. The output power at 1 dB compression point is measured as 22.4 dBm, and the power added efficiency of 17% is achieved at 1‐dB compression point. The chip area is significantly reduced by using lumped element impedance matching Wilkinson power dividers; the total die size is 1.2 × 1.25 mm2, including radio frequency (RF) and bias pads. The simulated (Cadence) and measured performance of combined power amplifier are well matched. Thus, the RF power amplifier and combiner/splitter circuits can be used for 5.2 GHz WLAN applications. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2413–2419, 2010; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25511
Miniaturized lowpass and bandstop filters using controlled coupling of open‐loop‐ring defected ground structure
Authors: Boutejdar A. , Omar A.
Published: August 2010

In this article, we present a compact microstrip bandstop filter using an open‐loop‐ring defected ground structure slot, etched in the ground plane and a simple Hi‐Lo line on the top layer. With the proposed coupling technique, a simple transformation from BSF to a corresponding LPF has been realized. The design procedure is validated using the commercial full‐wave simulator Microwave Office. The proposed BSF provides sharp transition characteristics, a wide upper stop band and improved passband response symmetry. Finally, the proposed filter structure has been fabricated and measured. The measurements are in a good agreement with the simulated results. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2575–2578, 2010; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25527
Compact fractal antenna with self‐complementary hilbert‐curves for WLAN dual‐band and circular polarization applications
Authors: Liu Ji‐Chyun , Zeng Bing‐Hao , Chen Hung‐Lin , Bor Sheau‐Shong , Chang Dau‐Chyrh
Published: August 2010

The authors propose a compact fractal antenna consisted of a Hilbert‐curve and self‐complementary configuration with dual‐band and circular polarization characteristics. This design merges the inductively loaded monopole antenna and the self‐complementary antenna to obtain a new monopole antenna. The self‐complementary Hilbert‐curve monopole antenna presents the desired bands of 2.43 GHz with bandwidth (BW) = 70 MHz (2.88%) and 5.35 GHz with BW = 550 MHz (10.36%). The circular polarizations for dual‐band are demonstrated with AR spectrum and orthogonal modes. The proposed antenna is successfully simulated and measured with frequency responses, radiation patterns, current distributions, and electric field intensities. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2535–2539, 2010; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25528
Slot tag antenna for highQRFID chip
Authors: Deleruyelle T. , Pannier P. , Egels M. , Bergeret E.
Published: August 2010

This article presents a radio frequency identification (RFID) tag slot antenna.This antenna is suitable for highQRFID chip. The input impedance at 915 MHz should be 19 +j492 Ω. Simulated maximum range is more than 8 m on Federal Communication Commission (FCC) RFID band and more than 3 m on the entire RFID band. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2493–2495, 2010; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25531
A novel photonic RF phase shifter based on polarization controller
Authors: Liu Ning , Chen Han , Li Jianhua , Yi Ping
Published: August 2010

A novel radio frequency (RF) photonic phase shifter based on polarization controller is presented and the theoretical fundamentals of the design are explained.This phase shifter provides broad operational bandwidth and a full 360° phase shift tuning range with a commercial polarization controller. A prototype of the RF photonic phase shifter with a frequency of 26.75 GHz and 360° tuning range is experimentally demonstrated. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2598–2600, 2010; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25533
A novel design of triplexer for GSM based on SIR
Authors: Garmjani N. Molaei , Komjani Nader
Published: August 2010

In this article, a triplexer is presented for three operation frequencies in GSM, based on stepped impedance resonators (SIR).SIR structures have some characteristics, such as low weight, little dimension, and the ability of providing filter behavior with different frequencies in same dimensions. To design the triplexer, bandpass filters of each output should be design first. Parallel connection of three filters together causes an extreme increase in insertion loss of each filter and also reflection of power to the input. A novel based‐on‐SIR matching circuit is proposed to solve these problems. By connecting optimized matching circuits to three bandpass filters [1], which are simulated for three frequency ranges in GSM, the desired triplexer is obtained. This based‐on‐SIR triplexer is simulated and fabricated. The measurement results of the fabricated prototype shows a good agreement with simulation results. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2563–2568, 2010; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25535
On‐board small‐size printed monopole antenna integrated with USB connector for penta‐band WWAN mobile phone
Authors: Wong Kin‐Lu , Chang Chih‐Hua
Published: August 2010

An on‐board small‐size printed two‐strip monopole antenna integrated with a universal series bus (USB) connector and generating two wide operating bands to cover penta‐band wireless wide area network operation in the 824–960/1710–2170 MHz bands is presented.The two strips of the antenna are respectively printed on two small no‐ground portions of 15 × 25 and 15 × 15 mm2 (total size 600 mm2). In‐between the two printed strips, there is a protruded ground of 15 × 10 mm2 to accommodate a USB connector, which serves as the data port of the mobile phone. Also, easy control of the antenna's two wide lower and upper bands can be achieved by respectively adjusting the longer and shorter strips of the printed monopole antenna. That is, the antenna is easy to fabricate and also easy to fine‐tune in practical applications. Details of the proposed antenna are presented and discussed. The radiation characteristics of the antenna, including the specific absorption rate results with the presence of the user's head and hand, are also studied. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2523–2527, 2010; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25537