bluuebunny/crossref_metadata_2025 huggingface dataset:
FRET analyses of the U2AF complex localize the U2AF35/U2AF65 interaction in vivo and reveal a novel self-interaction of U2AF35
Authors: CHUSAINOW JANET , AJUH PAUL M. , TRINKLE-MULCAHY LAURA , SLEEMAN JUDITH E. , ELLENBERG JAN , LAMOND ANGUS I.
Published: July 2005

We have analyzed the interaction between the U2AF subunits U2AF35 and U2AF65 in vivo using fluorescence resonance energy transfer (FRET) microscopy. U2 snRNP Auxiliary Factor (U2AF) is an essential pre-mRNA splicing factor complex, comprising 35-kDa (U2AF35) and 65-kDa (U2AF65) subunits. U2AF65 interacts directly with the polypyrimidine tract and promotes binding of U2 snRNP to the pre-mRNA branchpoint, while U2AF35 associates with the conserved AG dinucleotide at the 3′ end of the intron and has multiple functions in the splicing process. Using two different approaches for measuring FRET, we have identified and spatially localized sites of direct interaction between U2AF35 and U2AF65 in vivo in live cell nuclei. While U2AF is thought to function as a heterodimeric complex, the FRET data have also revealed a novel U2AF35 self-interaction in vivo, which is confirmed in vitro using biochemical assays. These results suggest that the stoichiometry of the U2AF complex may, at least in part, differ in vivo from the expected heterodimeric complex. The data show that FRET studies offer a valuable approach for probing interactions between pre-mRNA splicing factors in vivo.
Health Care Expenditures of Immigrants in the United States: A Nationally Representative Analysis
Authors: Mohanty Sarita A. , Woolhandler Steffie , Himmelstein David U. , Pati Susmita , Carrasquillo Olveen , Bor David H.
Published: July 2005

Objectives. We compared the health care expenditures of immigrants residing in the United States with health care expenditures of US-born persons.

Methods. We used the 1998 Medical Expenditure Panel Survey linked to the 1996–1997 National Health Interview Survey to analyze data on 18398 US-born persons and 2843 immigrants. Using a 2-part regression model, we estimated total health care expenditures, as well as expenditures for emergency department (ED) visits, office-based visits, hospital-based outpatient visits, inpatient visits, and prescription drugs.

Results. Immigrants accounted for $39.5 billion (SE=$4 billion) in health care expenditures. After multivariate adjustment, per capita total health care expenditures of immigrants were 55% lower than those of US-born persons ($1139 vs $2546). Similarly, expenditures for uninsured and publicly insured immigrants were approximately half those of their US-born counterparts. Immigrant children had 74% lower per capita health care expenditures than US-born children. However, ED expenditures were more than 3 times higher for immigrant children than for US-born children.

Conclusions. Health care expenditures are substantially lower for immigrants than for US-born persons. Our study refutes the assumption that immigrants represent a disproportionate financial burden on the US health care system.
Barriers to Care-Seeking for Children’s Oral Health Among Low-Income Caregivers
Authors: Kelly Susan E. , Binkley Catherine J. , Neace William P. , Gale Bruce S.
Published: July 2005

Objectives. We identified psychosocial, structural, and cultural barriers to seeking dental care among nonutilizing caregivers of Medicaid-enrolled children.

Methods. We used Medicaid utilization records to identify utilizing and nonutilizing African American and White caregivers of Medicaid-enrolled children in Jefferson County, Kentucky. We conducted 8 focus groups (N=76) with a stratified random sample of responding caregivers; transcripts were qualitatively analyzed.

Results. Psychosocial factors associated with utilization included oral health beliefs, norms of caregiver responsibility, and positive caregiver dental experiences. Utilizing groups reported higher education; health beliefs included identifying oral health with overall health and professional preventive dental care with caregiver responsibility for children’s overall health. These beliefs may mediate shared structural barriers, including transportation, school absence policies, discriminatory treatment, and difficulty locating providers who accept Medicaid. Expectation of poor oral health among some low-income caregivers was among factors identified with nonutilization.

Conclusions. Disadvantaged caregivers reported multiple barriers to accessing dental care for their children. Providers, Medicaid administrators, and schools must coordinate steps to encourage caregiver-controlled dental care, build trust, and link professional preventive dental care with caregiver responsibility for children’s overall health.
Mortality in US Army Gulf War Veterans Exposed to 1991 Khamisiyah Chemical Munitions Destruction
Authors: Bullman Tim A. , Mahan Clare M. , Kang Han K. , Page William F.
Published: July 2005

Objectives. We investigated whether US Army Gulf War veterans who were potentially exposed to nerve agents during the March 1991 weapons demolitions at Khamisiyah, Iraq, are at increased risk of cause-specific mortality.

Methods. The cause-specific mortality of 100487 exposed US Army Gulf War veterans was compared with that of 224980 unexposed US Army Gulf War veterans. Exposure was determined with the Department of Defense 2000 plume model. Relative risk estimates were derived from Cox proportional hazards models.

Results. The risks of most disease-related mortality were similar for exposed and unexposed veterans. However, exposed veterans had an increased risk of brain cancer deaths (relative risk [RR]=1.94; 95% confidence interval [CI]=1.12, 3.34). The risk of brain cancer death was larger among those exposed 2 or more days than those exposed 1 day when both were compared separately to all unexposed veterans (RR=3.26; 95% CI=1.33, 7.96; RR=1.72; 95% CI=0.95,3.10, respectively).

Conclusions. Exposure to chemical munitions at Khamisiyah may be associated with an increased risk of brain cancer death. Additional research is required to confirm this finding.
Timeliness of Childhood Immunizations: A State-Specific Analysis
Authors: Luman Elizabeth T. , Barker Lawrence E. , McCauley Mary Mason , Drews-Botsch Carolyn
Published: July 2005

Objective. We examined the timeliness of vaccine administration among children aged 24 to 35 months for each state of the United States and the District of Columbia.

Methods. We analyzed the timeliness of vaccinations in the 2000–2002 National Immunization Survey. We used a modified Bonferroni adjustment to compare a reference state with all other states.

Results. Receipt of all vaccinations as recommended ranged from 2% (Mississippi) to 26% (Massachusetts), with western states having less timeliness than eastern states.

Conclusions. Vaccination coverage measures usually focus on the number of vaccinations accumulated by specified ages. Our analysis of timeliness of administration shows that children rarely receive all vaccinations as recommended. State health departments can use timeliness of vaccinations along with other measures to determine children’s susceptibility to vaccine-preventable diseases and to evaluate the quality of vaccination programs. States can use the modified Bonferroni comparison to appropriately compare their results with other states.
An Analysis of Messages About Tobacco in Military Installation Newspapers
Authors: Haddock C. Keith , Parker L. Carrie , Taylor Jennifer E. , Poston Walker S.C. , Lando Harry , Talcott G. Wayne
Published: July 2005

Objectives. We sought to gauge the relative attention that tobacco control receives in military newspapers by comparing coverage of tobacco use with that of other health topics of importance to the military.

Methods. We examined tobacco-related articles and industry advertisements in 793 newspapers published during 1 year at 16 representative military installations (4 Air Force, 6 Army, 2 Marine, 4 Navy). Newspaper content was coded with a standardized coding manual developed through previous research.

Results. Tobacco use received the fewest instances of coverage and the least print space in military installation newspapers of all the health topics examined. The primary “message frame” used in tobacco control articles was that smokers are putting themselves at health risk, a theme that has not been found to have a strong effect on smokers. Nearly 10% of the newspapers contained tobacco advertisements.

Conclusions. Tobacco control messages are underrepresented in military installation newspapers compared with other health issues. Furthermore, military newspapers send mixed messages to military personnel by providing advertisements for tobacco while also claiming that tobacco use is harmful.
Preventive Dental Care and Unmet Dental Needs Among Low-Income Children
Authors: Kenney Genevieve M. , McFeeters Joshua R. , Yee Justin Y.
Published: July 2005

Objectives. We examined the ways in which levels of preventive dental care and unmet dental needs varied among subgroups of low-income children.

Methods. Data were drawn from the 2002 National Survey of America’s Families. We conducted bivariate and multivariate analyses, including logistic regression analyses, to assess relationships between socioeconomic, demographic, and health factors and receipt of preventive dental care and unmet dental needs.

Results. More than half of low-income children without health insurance had no preventive dental care visits. Levels of unmet dental needs among low-income children who had private health insurance coverage but no dental benefits were similar to those among uninsured children. Children of parents whose mental health was rated as poor were twice as likely to have unmet dental needs as other children.

Conclusions. Additional progress toward improving the dental health of low-income children depends on identifying and responding to factors limiting both the demand for and the supply of dental services. In particular, it appears that expanding access to dental benefits is key to improving the oral health of this population.
The ABCDs of Treating the Most Prevalent Childhood Disease
Authors: Donahue G. Jay , Waddell Nancy , Plough Alonzo L. , del Aguila Michael A. , Garland Tracy E.
Published: July 2005

Dental caries is a potentially preventable infectious disease that, untreated, can cause significant morbidity requiring costly treatment. The Access to Baby and Child Dentistry (ABCD) program increases access to prevention and early treatment for Medicaid-eligible children aged younger than 6 years in Washington State.

The program is a partnership of Washington Dental Service Foundation, the University of Washington School of Pediatric Dentistry, the state Medical Assistance Administration, and local stakeholders. Through training in pediatric dental techniques and enhanced reimbursement, ABCD equips and encourages dentists to serve young Medicaid patients. Family counseling increases oral care compliance and reduces no-show rates. Program evaluation demonstrates changing attitudes and behavior among participating families and dentists, with more young, low-income Washington children receiving oral health care.
Imaging Detectors
Authors: Blouke Morley M.
Published: July 2005

Charge‐coupled devices (CCDs) were first introduced in 1970 with the demonstration of an eight‐bit linear shift register. The concept of charge coupling was novel in the integrated circuit arena in that information was represented by discrete charge packets, which were manipulated in the device and, only at the output, converted to a voltage that could be measured. By operating in the charge domain, the charge‐coupled device is a true integrated circuit; it is impossible to make such a device from a collection of discrete components.

The serious development of Active Pixel Sensors began in the early 1990s, though their heritage hails from work done in the 1960s. Active pixel sensors get their name from the nature of the structure that makes up the pixel: a charge collection site and readout circuitry are provided within each pixel.

This article provides an overview of charge‐coupled devices and active pixel sensors, their design, structure, operation, and performance.
Electron Microscopy
Authors: Williams David B. , Goldstein Joseph I. , Lyman Charles E.
Published: July 2005

See also the updated overview article

.
Holography
Authors: Leith Emmett N.
Published: July 2005

Holography, a method of photography that produces highly realistic images, fully three‐dimensional, with the normal parallax relations of the actual object, is described. Basics of the theory are presented from both a mathematical and a physical viewpoint. Various areas of application are given, including three‐dimensional displays, complex spatial filtering, hologram interferometry for nondestructive testing and metrology, product authentication and counterfeiting security, holographic optical elements, and imaging through inhomogeneities using holographic phase conjugation. The various forms of white light viewable holograms are described, including the Denisyuk or volume type, the Benton or rainbow type, and the integral type. The diffractive properties of holograms are analyzed, including Bragg diffraction, i.e., diffraction from a volume hologram. The construction of commercial display holograms is discussed. The present state of commercial and artistic holography is discussed, along with expected future developments.
Lasers, Dye
Authors: Duarte Francisco J. , Foster David R.
Published: July 2005

Dye lasers are inherently tunable, and powerful, sources of narrow‐linewidth radiation. This means that dye lasers can change the emission color continuously while emitting radiation of extremely high spectral purity. In addition, these tunable lasers can be configured to yield extremely short pulses in the femtosecond regime. As such, dye lasers have found a wide variety of applications in fundamental physics, spectroscopy, medicine, and the military. In this article, basic aspects of dye‐laser operation are examined and explained. These include a discussion of the excitation process, via classical rate equations, the origin of tunability, and the theory of dispersion that explains the achievement of very narrow laser linewidths. Although most of the article deals with traditional liquid dye lasers, a section is devoted to newly developed solid‐state dye lasers. Important applications, such as laser isotope separation and laser cooling are also discussed.
Perturbation Methods
Authors: Murdock James
Published: July 2005

When a solvable mathematical problem is changed slightly, or perturbed, it may become unsolvable (in closed form). Perturbation theory enables an approximate solution to be constructed; in the simplest cases, this is done by adding successive correction terms to the solution of the unperturbed problem. The roots of the method, which lie in celestial mechanics, fluid flow, and quantum mechanics are briefly described. The notions of perturbation series, uniform asymptotic validity, and regular and singular problems are defined. In the area of nonlinear oscillations, the most important methods are the Lindstedt method (or method of strained coordinates), the method of multiple scales, and the method of averaging; these are described and compared. Special results for the averaging of multifrequency Hamiltonian systems, including the Kolmogorov–Arnol'd–Moser (KAM) theorem and the Nekhoroshev theorem, are briefly described. In dynamical systems, the Melnikov integral describes the perturbation of stable and unstable manifolds. Differential equations in which a small parameter multiplies the highest derivative lead to solutions having initial or boundary layers. The multiple‐scale method and methods of matched asymptotic expansions for these problems are described. The WKB method can also be used in certain cases. The matching method for partial differential equations is illustrated by the boundary layer problem for fluid flow. Finally, several approaches to the problem of finding the eigenvalues (spectra) of perturbed matrices and linear transformations are described.
Sensors, Optical
Authors: Haus Jörg , Schaefer Roland
Published: July 2005

In terms of dynamic range and noise, optical sensors have great advantages over their electronic or mechanical counterparts. In addition, the noncontact nature of all optical measurements avoids influences of the sensor on the measured value and, thus, measurement‐introduced systematic errors. This article gives an introduction to the components found in all kinds of optical sensors: light sources, detectors, and optical elements. On the basis of this optoelectronic toolbox, sensors for the measurement of various physical and chemical quantities are described.
Sonoluminescence
Authors: Sehgal Chandra M.
Published: July 2005

See also the updated overview article.
Thermoluminescence
Authors: McKeever Stephen W. S.
Published: July 2005

See also the updated overview article.
Optical Techniques for Mechanical Measurement
Authors: Wykes Catherine
Published: July 2005

It is possible to measure a range of mechanical properties using light. These include presence, position, displacement, velocity, acceleration, surface form, and surface finish. This article summarizes the various methods and outlines the factors that limit their measurement performance. Representative values for commercially available systems are quoted where they are available and examples of applications are cited. The techniques discussed are presence detection, surface finish, optical triangulation, laser radar, interferometry, laser Doppler vibrometry and laser Doppler anemometry, electronic speckle pattern interferometry, holographic interferometry, moiré methods, and vision systems.
Luminescence
Authors: Hofmann Detlev M. , Böhm Manfred
Published: July 2005

The article gives an introduction to the widespread phenomenon of light emission from matter under the aspect of the most common stimulation sources, that is, the use of photons for photoluminescence, or electron beams for cathodoluminescence, electric fields in the case of electroluminescence, chemical energy for chemiluminescence, sound waves for sonoluminescence, or thermal energy for the stimulation of the thermoluminescence phenomena. It focuses mostly on the respective principles of the luminescence excitation, rather than an overview of the uncountable applications of the methods in all areas of science, technology, and engineering.
Aggressive resection of the airway invaded by thyroid carcinoma
Authors: Tsai Y-F , Tseng Y-L , Wu M-H , Hung C-J , Lai W-W , Lin M-Y
Published: July 2005

Background

The aim of this study was to investigate the hypothesis that outcome following concomitant airway resection is superior to that after shaving of the tumour in patients with airway invasion of thyroid carcinoma.

Methods

The records of 34 patients with thyroid cancer with airway invasion were reviewed retrospectively. In addition to total thyroidectomy, airway resection was performed in 18 patients (group 1), whereas the tumour was shaved away from the airway in the other 16 patients (group 2). 131I was used as postoperative adjuvant therapy in all patients. Metastasis and recurrence of the primary lesion were determined by 131I whole-body scans, serum thyroglobulin levels, and computed tomography or ultrasonography of the neck.

Results

In group 1, two anastomotic dehiscences resulted in one death. Patients in group 2 had a higher rate of local recurrence (relative risk 8·0, P = 0·013) and earlier recurrence (mean(s.e.m.) 2·6(0·8) versus 7·0(1·1) years; P = 0·026) than those in group 1. Median survival was 5·8 and 4·3 years in the 18 patients of group 1 and 16 patients of group 2 (P = 0·259), and the respective 5-year survival rates were 88 and 84 per cent (P = 0·783).

Conclusion

Aggressive airway resection can minimize local recurrence of thyroid carcinoma with airway invasion.
Synthesis, Photophysics, and Photoresponse of Fullerene‐Based Azoaromatic Dyads
Authors: Possamai Giorgia , Marcuz Silvia , Maggini Michele , Menna Enzo , Franco Lorenzo , Ruzzi Marco , Ceola Stefano , Corvaja Carlo , Ridolfi Giovanni , Geri Alessandro , Camaioni Nadia , Guldi Dirk M. , Sens Ruediger , Gessner Thomas
Published: July 2005

The synthesis and photophysical characterization of a series of fullerene‐based, donor–acceptor dyads is presented, along with a description of their behavior as single molecular components in photovoltaic cells. The spectroscopic and photophysical properties of the dyads, investigated by steady‐state fluorescence spectroscopy, pico‐ and nanosecond transient optical spectroscopy and time‐resolved electron paramagnetic resonance (EPR) spectroscopy, revealed that the dyads undergo multiple‐step energy transfer from the donor singlet excited state to the fullerene triplet excited state, which in turn decays to the donor triplet state. The inefficient formation of a charge‐separated state, both in solution and in the solid state, translates into a poor photovoltaic performance of dyads 2 b–4 b if compared to that of dyad 1 b, in which photoinduced electron transfer is operative in the solid state. In addition, the results of the photophysical investigation suggested that the performance of the solar cells was also limited by the low‐lying donor triplet excited state that acts as a photoexcitation energy sink.
Transforming growth factor‐beta 1 (TGF‐β1) prevents the age‐dependent decrease in bone formation in human osteoblast/implant cultures
Authors: Zhang Hai , Aronow Michael S. , Gronowicz Gloria A.
Published: July 2005

Titanium implants have been extensively used in orthopedic surgery and dentistry. Most of the patients who receive such implants are elderly with a compromised ability to heal and form new bone. By using an in vitro osteoblast/implant culture system, the potency of TGF‐β1 in enhancing mineralization of human osteoblast cultures from elderly subjects was investigated in this study. Primary human osteoblast (HOB) cells obtained from different age group human subjects [Young (Y), Middle (M), and Old (O)] were cultured on Ti alloy (Ti‐6Al‐4V) disks with or without continuous administration of 0.2 ng/mL TGF‐β1 in the medium for 2 or 4 weeks. TGF‐β1 significantly (p < 0.05) increased calcium content and the size of calcified nodules on implant disks in the O group, but had no effect on the Y or M groups. The number of calcified nodules was not different with or without TGF‐β1 in all age groups. As measured by Northern blot analysis and RT‐PCR, TGF‐β1 significantly increased the expression of bone‐specific extracellular matrix proteins, including alkaline phosphatase, Type I collagen, bone sialoprotein and osteocalcin, after both 2 and 4 weeks in the O group but not in the Y group. In conclusion, TGF‐β1 enhances mineralization on implant materials of osteoblast cultures from elderly human subjects. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res, 2005
In vitro evaluation of platelet reactivity toward annuloplasty devices treated with heparin coating: Studies under flow conditions
Authors: Tonda R. , Galán A. M. , Pino M. , Hernández M. R. , Ayats C. , Pomar J. L. , Ordinas A. , Escolar G.
Published: July 2005

We have applied an in vitro perfusion model to explore the potential thrombogenicity of polyester annulolasty fabric used in valve repair and to investigate the possible thromboresistance characteristics conferred by a special heparin coating (Duraflo™ treatment). Samples of human blood from i) untreated or ii) heparin‐coated extracorporeal circuits were recirculated through annular perfusion chambers containing a) untreated or b) treated annuloplasty cloth material. Perfusion experiments were performed at a shear rate of 600 s−1 for 20 min. Platelet interaction with the material was morphometrically evaluated. In experiments performed with blood from untreated circuits and cloth material, the average cross‐sectional area of platelet mass was 615 ± 135 μm2. Treatment of cloth material with Duraflo™ statistically decreased the area of interacting platelets to 319 ± 101 μm2 (*p < 0.05, n = 10). Blood samples from heparin‐coated extracorporeal circuits showed a decrease of total area of platelets (308 ± 58 μm2 vs 138 ± 30 μm2, *p < 0.05, n = 9). The combined treatment of Duraflo™ in extracorporeal circuits and cloth material caused a more consistent reduction (p < 0.05). The in vitro perfusion experimental model was sensitive to evaluate the thrombogenic potential of Duraflo™ treatment. Our results indicate that the heparin coating of cloth material and extracorporeal circuits improves the biocompatibility of the original material and reduces the thrombogenic profile. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res, 2005
Selective inhibition of type X collagen expression in human mesenchymal stem cell differentiation on polymer substrates surface‐modified by glow discharge plasma
Authors: Nelea Valentin , Luo Li , Demers Caroline N. , Antoniou John , Petit Alain , Lerouge Sophie , R. Wertheimer Michael , Mwale Fackson
Published: July 2005

Recent evidence indicates that a major drawback of current cartilage‐ and disc‐tissue engineering is that human mesenchymal stem cells (MSCs) rapidly express type X collagen—a marker of chondrocyte hypertrophy associated with endochondral ossification. Some studies have attempted to use growth factors to inhibit type X collagen expression, but none to date has addressed the possible effect of the substratum on chondrocyte hypertrophy. Here, we sought to examine the growth and differentiation potential of human MSCs cultured on two polymer types, polypropylene and nylon‐6, both of which have been surface‐modified by glow discharge plasma treatment in ammonia gas. Cultures were performed for up to 14 days in Dulbecco's modified Eagle medium + 10% fetal bovine serum. Commercial polystyrene culture dishes were used as control. Reverse transcriptase‐polymerase chain reaction was used to assess the expression of types I, II, and X collagens and aggrecan using gene‐specific primers. Glyceraldehyde‐3‐phosphate dehydrogenase was used as a housekeeping gene. Types I and X collagens, as well as aggrecan, were found to be constitutively expressed by human MSCs on polystyrene culture dishes. Whereas both untreated and treated nylon‐6 partially inhibited type X collagen expression, treated polypropylene almost completely inhibited its expression. These results indicate that plasma‐treated polypropylene or nylon‐6 may be a suitable surface for inducing MSCs to a disc‐like phenotype for tissue engineering of intervertebral discs in which hypertrophy is suppressed. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res, 2005
Deterministic global optimization of molecular structures using interval analysis
Authors: Lin Youdong , Stadtherr Mark A.
Published: July 2005

The search for the global minimum of a molecular potential energy surface is a challenging problem. The molecular structure corresponding to the global minimum is of particular importance because it usually dictates both the physical and chemical properties of the molecule. The existence of an extremely large number of local minima, the number of which may increase exponentially with the size of the molecule, makes this global minimization problem extremely difficult. A new strategy is described here for solving such global minimization problems deterministically. The methodology is based on interval analysis, and provides a mathematical and computational guarantee that the molecular structure with the global minimum potential energy will be found. The technique is demonstrated using two sets of example problems. The first set involves a relatively simple potential model, and problems with up to 40 atoms. The second set involves a more realistic potential energy function, representative of those in current use, and problems with up to 11 atoms. © 2005 Wiley Periodicals, Inc. J Comput Chem 26: 1413–1420, 2005
Biological and chemical inhibitors of NF‐κB sensitize SiHa cells to cisplatin‐induced apoptosis
Authors: Venkatraman Manickam , Anto Ruby John , Nair Asha , Varghese Merina , Karunagaran Devarajan
Published: July 2005

Cisplatin, a chemotherapeutic agent, is known to induce apoptosis of cancer cells. We examined the role of NF‐κB during cisplatin‐induced apoptosis in two human cervical cancer cell lines, HeLa and SiHa, known to differ in their response to cisplatin treatment. We found that SiHa cells were relatively more resistant than HeLa cells to the cytotoxic effects induced by cisplatin as measured by MTT assays. HeLa cells were more sensitive to the apoptotic effects induced by cisplatin as shown by increases in annexin staining, DNA fragmentation, and loss of mitochondrial membrane potential. Similarly the activities of caspases 3, 8, and 9 and cleavage of PARP induced by cisplatin were more in HeLa than SiHa cells. Cisplatin induced NF‐κB DNA binding activity in HeLa and SiHa cells but not in primary cervical cells and the active DNA binding complex in SiHa cells consists of p50 and RelA heterodimers. However, when NF‐κB DNA binding activity was blocked by chemical (curcumin, PDTC, or salicylic acid) or biological inhibitors (NIK‐KM or IKK‐β DN), the cell viability was less in SiHa cells with cisplatin treatment, but these effects were not observed in HeLa cells. Similarly upon treatment with cisplatin SiHa cells had more activation of caspases compared to that seen in HeLa cells under conditions of NF‐κB inhibition by biological or chemical inhibitors. These results suggest that NF‐κB may contribute to the resistance of human cervical cancer cells to cisplatin and highlight the potential use of combination therapy involving cisplatin and NF‐κB inhibitors. © 2005 Wiley‐Liss, Inc.
Current trends in the structure—activity relationship studies of the endogenous agouti‐related protein (AGRP) melanocortin receptor antagonist
Authors: Wilczynski Andrzej M. , Joseph Christine G. , Haskell‐Luevano Carrie
Published: July 2005

Agouti‐related protein (AGRP) is an endogenous antagonist of the melanocortin‐3 and ‐4 (MC3R and MC4) G‐protein coupled receptors. The 87–132 amino acid C‐terminal domain of hAGRP possesses five disulfide bridges and a well‐defined three‐dimensional structure that displays full biological activity as compared to the full‐length protein. Based on the NMR structure of the C‐terminal AGRP(87–132), a novel mini‐protein, referred to as “Mini‐AGRP” was designed that exhibited receptor binding affinity and antagonism similar to that of the parent hAGRP(87–132) protein. It was demonstrated that this new‐engineered protein autonomously folds to the inhibitor cystine knot (ICK) motif. As this AGRP is a novel mammalian protein involved in energy homeostasis and possibly other physiological functions remaining to be identified, structure‐function studies are starting to emerge toward the understanding of how this unique protein putatively interacts with the melanocortin receptors with the objective of designing potential therapeutic agents for in vivo physiological studies. This article summarizes the progress to date of AGRP‐based structure–activity relationships and putative ligand–receptor interactions. © 2005 Wiley Periodicals, Inc.
The folding landscape of an α‐lytic protease variant reveals the role of a conserved β‐hairpin in the development of kinetic stability
Authors: Truhlar Stephanie M. E. , Agard David A.
Published: July 2005

Most secreted bacterial proteases, including α‐lytic protease (αLP), are synthesized with covalently attached pro regions necessary for their folding. The αLP folding landscape revealed that its pro region, a potent folding catalyst, is required to circumvent an extremely large folding free energy of activation that appears to be a consequence of its unique unfolding transition. Remarkably, the αLP native state is thermodynamically unstable; a large unfolding free energy barrier is solely responsible for the persistence of its native state. Although αLP folding is well characterized, the structural origins of its remarkable folding mechanism remain unclear. A conserved β‐hairpin in the C‐terminal domain was identified as a structural element whose formation and positioning may contribute to the large folding free energy barrier. In this article, we characterize the folding of an αLP variant with a more favorable β‐hairpin turn conformation (αLPβ‐turn). Indeed, αLPβ‐turn pro region‐catalyzed folding is faster than that for αLP. However, instead of accelerating spontaneous folding, αLPβ‐turn actually unfolds more slowly than αLP. Our data support a model where the β‐hairpin is formed early, but its packing with a loop in the N‐terminal domain happens late in the folding reaction. This tight packing at the domain interface enhances the kinetic stability of αLPβ‐turn, to nearly the same degree as the change between αLP and a faster folding homolog. However, αLPβ‐turn has impaired proteolytic activity that negates the beneficial folding properties of this variant. This study demonstrates the evolutionary limitations imposed by the simultaneous optimization of folding and functional properties. Proteins 2005. © 2005 Wiley‐Liss, Inc.
Contribution of three‐dimensional volume contrast imaging to the sonographic assessment of the fetal uterus
Authors: Jouannic J.‐M. , Rosenblatt J. , Demaria F. , Jacobs R. , Aubry M.‐C. , Benifla J.‐L.
Published: July 2005

Objective

To investigate the contribution of volume contrast imaging (VCI) in assessing the fetal uterus in normally developed female fetuses.

Methods

The pelvis of 38 normal female fetuses was examined at 20–22 and 32–34 weeks' gestation using both conventional two‐dimensional (2D) ultrasound and VCI on the same transverse or oblique longitudinal view of the fetal pelvis. Two experienced sonographers evaluated the ability of both techniques to image the fetal uterus. Results were compared by kappa index to evaluate the interobserver variability.

Results

A clear picture of the fetal uterus was obtained in 50% and 82–87% of the cases at 20–22 weeks' gestation and in 80–85% and 95–100% of the cases at 32–34 weeks' gestation using conventional 2D ultrasound and VCI, respectively. There was moderate to good agreement of uterus visualization between the two observers, with kappa values ranging from 0.43 to 0.65. The lower level of agreement was obtained for conventional 2D ultrasound during the second trimester.

Conclusions

Our results suggest that VCI may be successfully applied to prenatal ultrasonography of the fetal pelvis anatomy. By enhancing the contrast between the intrapelvic organs, VCI provides a clearer picture of the fetal uterus. Copyright © 2005 ISUOG. Published by John Wiley & Sons, Ltd.
Factors influencing the success of conservative treatment of interstitial pregnancy
Authors: Cassik P. , Ofili‐Yebovi D. , Yazbek J. , Lee C. , Elson J. , Jurkovic D.
Published: July 2005

Objective

To identify demographic, morphological and biochemical characteristics of interstitial pregnancies that are associated with a successful outcome of conservative treatment (expectant management or medical treatment with methotrexate).

Methods

Over a period of 6 years all clinically stable women with a certain ultrasound diagnosis of interstitial ectopic pregnancy were managed either expectantly (no interventions) or medically (systemic or local methotrexate injection). The outcome of conservative treatment was compared to a number of diagnostic parameters, which were recorded at the initial visit. The treatment was classified as successful if serum human chorionic gonadotropin (hCG) level declined below 20 IU/L without the need for any additional interventions, such as the administration of methotrexate or surgery.

Results

A total of 42 interstitial pregnancies were diagnosed during the study period. Out of 35 women included in the final analysis 7 (20%) were managed expectantly and 28 (80%) received either local (n = 23) or systemic methotrexate (n = 5). There were no significant differences in the success rates of expectant treatment and treatment with either systemic or local methotrexate. The initial median serum hCG was significantly lower in women with successful conservative management (3216 IU/L vs. 15 900 IU/L; P < 0.05) but there were no other significant differences between cases with successful and failed treatment.

Conclusion

The measurement of serum hCG at the initial visit may be used to predict the likelihood of successful conservative treatment of interstitial pregnancy. Copyright © 2005 ISUOG. Published by John Wiley & Sons, Ltd.
Collectin surfactant protein D binds antibodies and interlinks innate and adaptive immune systems
Authors: Nadesalingam Jeya , Reid Kenneth B.M. , Palaniyar Nades
Published: July 2005

Innate immune collectins, such as surfactant protein D (SP‐D), contain fibrillar collagen‐like regions and globular carbohydrate‐recognition domains (CRDs). SP‐D recognizes carbohydrate arrays present on microbial surfaces via its CRDs, agglutinates microbes and enhances their phagocytosis. In contrast, adaptive immune proteins such as immunoglobulins (Igs) recognize pathogens via binding to specific antigens. Here we show that: SP‐D binds various classes of immunoglobins, including IgG, IgM, IgE and secretory IgA, but not serum IgA; the globular domains of SP‐D bind both the Fab and Fc domains of IgG; SP‐D recognizes IgG via calcium‐dependent protein–protein interactions, aggregates IgG‐coated beads and enhances their phagocytosis by murine macrophage RAW 264.7 cells. Therefore, we propose that SP‐D effectively interlinks innate and adaptive immune systems.
Late Quaternary glacial and climate history of the Pamir Mountains derived from cosmogenic 10Be exposure ages
Authors: Zech Roland , Abramowski Uwe , Glaser Bruno , Sosin Pjotr , Kubik Peter W. , Zech Wolfgang
Published: July 2005

Moraines southwest of Lake Yashilkul, Pamir, Tajikistan, were dated using 10Be exposure ages of boulder surfaces. We found evidence for (1) an extensive glaciation ∼60,000 yr ago; (2) a less extensive glacial advance, which deposited a characteristic hummocky moraine lobe with exposure ages ranging from ∼11,000 to 47,000 yr, probably deposited at or before 47,000 yr ago; and (3) lateral moraines with exposure ages of ∼40,000 yr, 27,000 yr and 19,000 yr, respectively. Increasing aridity in the Pamir is most likely responsible for the progressively limited extent of the glaciers during the Late Pleistocene.
Polar filament discharge of Myxobolus cerebralis actinospores is triggered by combined non-specific mechanical and chemical cues
Authors: KALLERT D. M. , EL-MATBOULI M. , HAAS W.
Published: July 2005

This study presents initial evidence for the requirement of both chemical and mechanical stimuli to discharge polar capsules of Myxobolus cerebralis actinospores, the causative agent of salmonid whirling disease. The obligate need for combined discharge triggers was concluded from data obtained in a before/after experimental set-up carried out with individual locally immobilized actinospores. Homogenized rainbow trout mucus as chemostimulus and tangency of the apical region of the spores to achieve mechanical stimulation were applied subsequently. The actinospores showed discharged polar filaments exclusively when mucus substrate application was followed by touching the polar capsule-bearing region, but not when either stimulus was offered solely to the same individuals. We measured filament discharge rates to mucus preparations in a microscopic assay using supplementary vibration stimuli to ensure mechanical excitation. The actinospores responded similarly to different frequencies, which suggested a touch-sensitive recognition mechanism. Discharge specificity for salmonid mucus could not be confirmed, as mucus of common carp and bream could trigger similar filament expulsion rates. To a lesser extent homogenized frog epidermis and bovine submaxillary mucin could also stimulate the attachment reaction. In contrast, mucus of a pulmonate freshwater snail elicited no response.
Frugivores and seed removal at Tetragastris altissima (Burseraceae) in a fragmented forested landscape of French Guiana
Authors: Ratiarison Sandra , Forget Pierre-Michel
Published: July 2005

We aimed at (1) determining how community-wide disruptions affect visitation by frugivores at trees and (2) estimating the impact of visitation shifts on seed fate following fruit consumption, especially seed removal. We compared the seed fate of a frugivore-dispersed tree species (Tetragastris altissima, Burseraceae) in four forested islands with that for a mainland continuous forest at Saint-Eugène, French Guiana. Tetragastris trees attracted opportunistic frugivore species available in the area, the most productive trees attracting more consumer species. Only primates, which are more susceptible to forest disturbances than birds and have low abilities to cross a non-forested matrix, were more frequent at Tetragastris on the mainland than on islands. Only opportunistic frugivorous primate species acting as low-efficiency seed dispersers were recorded. As a result, seed removal was equally low among habitats (nearly 26%), high percentages of seeds dropping below tree crowns. The scarcity of large-bodied specialist frugivorous primates throughout the landscape probably explained this low removal. Our results underline how difficult it is to generalize the cascading effects of disruptions in a frugivore community on tree seed fate, these effects likely varying according to the tree species and animal community involved.
Relationships among arbuscular mycorrhizas, root morphology and seedling growth of tropical native woody species in southern Brazil
Authors: Zangaro Waldemar , Nishidate Fabio Rodrigo , Camargo Flavia Regina Spago , Romagnoli Graziela Gorete , Vandressen Julia
Published: July 2005

The relationships between arbuscular mycorrhizal fungi and root morphological characteristics were studied under greenhouse conditions of 78 tropical native woody species and 47 seedling species collected in the field. Seedlings of native woody pioneer and early secondary species that generally exhibited fine roots with a dense cover of long root hairs showed higher mycorrhizal response and root mycorrhizal colonization than late-secondary and climax species with coarse roots with a sparse cover of short root hairs. Root-hair length and incidence decreased with the progression among the successional groups while fine-root diameter increased, both in the greenhouse and in the field. The mycorrhizal response was highly correlated to root mycorrhizal colonization in the greenhouse and in the field. These parameters were inversely correlated with the seed mass and fine-root diameter, but directly correlated with root-hair incidence, both in the greenhouse and in the field. Mycorrhizal response and root mycorrhizal colonization were also directly correlated with the root-hair length and root/shoot ratio of uninoculated plants. The seedling mycorrhizal status of the early successional woody species suggests that the root traits of these fast-growing species can be more receptive to attraction, infection and colonization by arbuscular mycorrhizas than root traits of late-successional species.
Evidence for direct water absorption by the shoot of the desiccation-tolerant plant Vellozia flavicans in the savannas of central Brazil
Authors: Oliveira Rafael S. , Dawson Todd E. , Burgess Stephen S. O.
Published: July 2005

Our common view on water uptake by terrestrial plants is that it occurs via absorption by roots from the soil substrate. However, it has long been known that plants exhibit alternative water-absorption strategies, particularly in drought-prone environments. Examples include many tropical epiphytic orchids which use a specialized structure called velamen radicum around their aerial roots for moisture absorption directly from the air (Capesius & Barthlott 1975), specialized trichomes in bromeliads (Andrade 2003, Benzing 1990), uptake by hydathodes into leaves of species inhabiting dry desert ecosystems of Namibia (Martin & von Willert 2000) and foliar absorption by coastal California redwoods during the summer fog season (Burgess & Dawson 2004). One of the most intriguing and yet, least-studied examples of adaptations to severe water limitation is found with desiccation-tolerant plants (also called resurrection plants). During drought periods, the water content of these plants can equilibrate with the low relative humidity of the air to the point that the plants appear dead. However, when water is supplied, these plants fully rehydrate (Alpert 2000, Bewley & Krochko 1982) and become physiologically active. Desiccation-tolerant vascular plants are rare in most ecosystems but diverse in tropical inselbergs (granitic outcrops; Porembski & Barthlott 2000). Relatively little is known about inselberg species particularly from an ecophysiological perspective (see Lüttge 1997 and Klüge & Brulfert 2000 for reviews).
On the relationships between double‐onset substorm, pseudobreakup, and IMF variation: The 4 September 1999 event
Authors: Cheng Ching‐Chang , Russell Christopher T. , Reeves Geoff D. , Connors Martin , Moldwin Mark B.
Published: July 2005

The relationships between double‐onset substorm, pseudobreakup, and IMF variation were investigated with magnetic, auroral, and particle observations from space to the ground during 0200–0600 UT on 4 September 1999. There were five consecutive bursts of Pi2 pulsations on the ground during the time of interest. The onset time of ground Pi2s maps to the same variation sequence in the IMF structure seen propagating to the Earth in multiple satellite observations in the upstream region. The comparison of auroral and energetic particle data with IMF observations shows that a sequence of two double‐onset substorms intervened by a pseudobreakup appears in two distinct cycles of southward IMF followed by a northward interval. For the first substorm, the first onset begins when the By magnitude declines after the IMF turns southward for about 90 min, and the second onset occurs after northward turning of the IMF accompanied by an increasing By magnitude. The pseudobreakup appears while the IMF turns southward and the By magnitude slightly decreases. For the second substorm, the first onset commences while the IMF remains southward with a steady By magnitude, and the second onset occurs after the IMF becomes strongly northward and the By magnitude decreases instead. These observations can be explained with the two‐neutral‐point model. The first onset occurs when the IMF turns southward. Reconnection at the near‐Earth neutral point first begins on closed field lines within the plasma sheet, and the second onset occurs when the IMF turns northward and reconnection at the distant neutral point ceases and reconnection at the near‐Earth neutral point may reach the open flux of the tail lobes. In addition, a decrease in the By magnitude may help reduce magnetotail convection and release all the built‐up flux to allow the onset to commence after northward turning of the IMF. If the IMF remains southward, the reduction of magnetotail convection due to a decreasing By would lead to a pseudobreakup instead. In contrast, an increasing By magnitude would increase magnetotail convection and weaken magnetospheric substorm after the IMF turns northward. Consequently, for the occurrence of double‐onset substorms and pseudobreakups, not only the first onset begins spontaneously during steady southward IMF and the second onset appears after northward turning of the IMF but the By change also affects magnetotail convection which may evoke (or abate) the substorm‐related activation while the IMF turns southward (or northward).