bluuebunny/crossref_metadata_2025 huggingface dataset:
Molecular cloning and characterization of a new gene, Oocyte‐G1
Authors: Zhang Yong , Wu Ji
Published: August 2008

Oocytes are recognized as a source of regulatory molecules that influence follicular development through an array of actions on granulosa cells. Recently, more and more hormones and signaling molecules were identified during follicular developmental processes; however, the details about their functions are still unclear. During efforts to clone follicular development‐related genes, we isolated a cDNA fragment by DDRT‐PCR. To obtain cDNA 5′‐ and 3′‐end sequences, we screened a mouse ovarian cDNA library. After screening the library, an open reading frame of 2,994 bp for the new gene (Oocyte‐G1), which encodes a 997‐residue protein, was cloned. Northern blot analysis revealed the presence of ∼3.6 kb Oocyte‐G1 mRNA in ovary, lung, kidney, testis and brain. Northern analysis of RNA from ovaries in vivo showed that Oocyte‐G1 was weakly expressed on day 5 and at a moderate level on day 10. Thereafter, on day 15 or in adults (day 40), there was an increase in expression, followed by a decline in ovaries on day 20 or older (day 120). Furthermore, we studied the Ooctye‐G1 protein by using the antiserum against a peptide sequence unique to this gene in Western blotting and immunolocalization. The antiserum recognized a prominent band of ∼110 kDa in immunoblots and signals were dispersed in oocytes and some cumulus granulosa cells. Our results suggest the potential role of Oocyte‐G1 in ovarian follicular development. J. Cell. Physiol. 218: 75–83, 2009. © 2008 Wiley‐Liss, Inc.
Thrombospondin‐1‐induced apoptosis of brain microvascular endothelial cells can be mediated by TNF‐R1
Authors: Rege Tanya A. , Stewart Jerry , Dranka Brian , Benveniste Etty N. , Silverstein Roy L. , Gladson Candece L.
Published: August 2008

Thrombospondin‐1 (TSP‐1) treatment of dermal microvascular endothelial cells (MvEC) has been shown to upregulate Fas ligand (FasL) and to induce apoptosis by a mechanism that requires caspase‐8 activity. We have examined the potential anti‐angiogenic effects of TSP‐1 on primary human brain MvEC. The addition of TSP‐1 to primary human brain MvEC cultured as monolayers on type 1 collagen, induced cell death and apoptosis (evidenced by caspase‐3 cleavage) in a dose‐ (5–30 nM) and time‐dependent (maximal at 17 h) manner. TSP‐1 treatment for 17 h induced caspase‐3 cleavage that required caspase‐8 activity and the tumor necrosis factor receptor 1 (TNF‐R1). We did not find a requirement for Fas, or the tumor necrosis‐related apoptosis‐inducing ligand receptors (TRAIL‐R) 1 and 2. We confirmed the findings using caspase inhibitors, blocking antibodies and small interfering RNA (siRNA). Further analysis indicated that the TSP‐1 induction of caspase‐3 cleavage of primary human brain MvEC adherent to collagen required the synthesis of new message and protein, and that TSP‐1 induced the expression of TNFα mRNA and protein. Consistent with these findings, when the primary human brain MvEC were propagated on collagen gels mAb anti‐TNF‐R1 reversed the inhibitory effect, in part, of TSP‐1 on tube formation and branching. These data identify a novel mechanism whereby TSP‐1 can inhibit angiogenesis‐through induction of apoptosis in a process mediated by TNF‐R1. J. Cell. Physiol. 218: 94–103, 2009. © 2008 Wiley‐Liss, Inc.
Inhibition of myogenesis by Notch: Evidence for multiple pathways
Authors: Buas Matthew F. , Kabak Shara , Kadesch Tom
Published: August 2008

Notch signaling is critical for skeletal muscle development and regeneration, permitting the expansion of progenitor cells by preventing premature differentiation. We have interrogated the pathways through which ligand‐mediated signaling inhibits myogenesis by identifying Notch target genes and assessing their impact on differentiation in vitro. Notch activation led to the robust induction of the transcriptional repressors Hey1 and HeyL in myoblasts, but only constitutive expression of Hey1 blocked myogenesis. siRNA‐mediated knockdown of Hey1 had no effect on Notch's ability to inhibit differentiation, suggesting the existence of additional, possibly redundant pathways. We identified 82 genes whose expression was activated when C2C12 myoblasts were cultured in the presence of the Notch ligand Dll4. One of these, MyoR, is a novel Notch‐responsive gene, whose protein product is known to repress myogenesis in vitro. siRNA‐mediated knockdown of MyoR alone, or in combination with Hey1, was also ineffective at rescuing differentiation in the presence of Dll4. Our data support a model in which Notch signaling inhibits myogenesis through multiple pathways, two of which are defined by the Notch target genes Hey1 and MyoR. J. Cell. Physiol. 218: 84–93, 2009. © 2008 Wiley‐Liss, Inc.
The use of mesenchymal (skeletal) stem cells for treatment of degenerative diseases: Current status and future perspectives
Authors: Abdallah Basem M. , Kassem Moustapha
Published: August 2008

Human bone marrow derived‐mesenchymal (skeletal) stem (MSC) cells are a group of non‐hematopoietic stem cells residing in the perivascular niches in bone marrow. These cells have the capacity to differentiate mainly into mesoderm‐type cells such as osteoblasts, chondrocytes and adipocytes and possibly but not proven to non‐mesodermal cell types. Recently, there has been an increased interest in understanding the biology of MSC due to their potential use in cell‐based therapy for multiple degenerative diseases. Here, we will provide an update on the current status of these novel therapeutic opportunities. J. Cell. Physiol. 218: 9–12, 2009. © 2008 Wiley‐Liss, Inc.
Sonographic assessment of uterine and ovarian development in normal girls aged 1 to 12 years
Authors: Badouraki Maria , Christoforidis Athanasios , Economou Ippoliti , Dimitriadis Athanassios S. , Katzos George
Published: August 2008

Purpose.

To provide normal references of sonographic uterine and ovarian size in girls aged 1–12 years.

Method.

Ninety‐nine girls were enrolled in the study (mean age ± SD, 6.9 ± 2.4 years [range, 1–12 years]). Pubertal status was classified according to Tanner staging, whereas for height and weight assessment a standard stadiometer and weight scale were employed. All subjects underwent pelvic sonographic examination for the measurement of uterine length, volume, ratio of anteroposterior diameter at the fundus divided by the anteroposterior diameter at the cervix (fundal–cervical [F/C] ratio), and ovarian volume and morphology.

Results.

A gradual increase with age was observed in all uterine and ovarian measurements. Cubic model analysis provided the best curve estimation for uterine length, uterine volume, and ovarian volume in relation to age. Uterine length, uterine volume, ovarian volume and F/C ratio were significantly correlated to both age and height. With respect to ovarian morphology, there was a gradual decrease in frequency of the homogeneous and the paucicystic appearances with increasing age. The macrocystic appearance was observed after the age of 6 years, and its frequency increased gradually with age.

Conclusion.

There is a continuous increase in size of internal female genitalia from early childhood until the onset of puberty. We have provided reference percentile charts of normal uterine length, uterine volume, and ovarian volume in girls aged 1–12 years. © 2008 Wiley Periodicals, Inc. J Clin Ultrasound, 2008
The role of evaporation in the energy balance of an open‐air scaled urban surface
Authors: Pearlmutter D. , Krüger E. L. , Berliner P.
Published: August 2008

Surface evaporation is an important component of the urban energy balance, and its role in arid‐zone cities may significantly differ from that observed in more temperate regions. However, the quantification of evapotranspiration is difficult in a complex urban setting, given the heterogeneity of the terrain and its various dry and wet elements. Here an open‐air scaled urban surface (OASUS) is employed to quantify latent heat flux as a function of the surface area available for evaporation and the three‐dimensional (3‐D) urban geometry. The OASUS model consists of an extensive urban‐like building/street array located in an arid Negev region of southern Israel (30.8°N, 480 m above sea level). Measurements were carried out during the summer month of August, and flux partitioning was analysed using evaporation pans of varying surface areas embedded in arrays of varying height. Results indicated that the increase in latent heat removal with respect to equivalent ‘vegetative’ surface area was nearly linear. Increasing latent heat flux with ‘vegetated fraction’ was offset in approximately equal measure by decreases in storage and turbulent sensible heat flux. The proportion of the radiant energy budget represented by evaporative heat loss was also linked to the 3‐D geometry of the array, increasing linearly with the ratio between vegetative cover and the ‘complete’ urban surface area. Copyright © 2008 Royal Meteorological Society
Timing of the late Quaternary glaciation in the Andes from ∼15 to 40° S
Authors: Zech Roland , May Jan‐Hendrik , Kull Christoph , Ilgner Jana , Kubik Peter W. , Veit Heinz
Published: August 2008

The Central Andes play a pivotal role for glacier and climate reconstruction along the American Pole–Equator–Pole transect. Nevertheless, knowledge about late Quaternary palaeoenvironmental changes in this region is extremely limited. With the advent and application of surface exposure dating during the last few years, the establishment of more detailed glacial chronologies could provide important insights into forcings and mechanisms of glaciation and climate change. This paper reviews previously published exposure ages and compares them with independent age control on glacial chronologies and with information about the palaeohydrological conditions. Although available data are still very limited and there are remaining systematic uncertainties related to surface exposure dating, the following simplified palaeoglacial/palaeoclimate model is presented to serve as a testable hypothesis for future studies. (i) Glaciers in the humid tropical Andes were mainly temperature sensitive and therefore advanced during temperature minima. Advances are dated to 20–25 ka, ∼15 ka and 11–13 ka, i.e. synchronous to the global Last Glacial Maximum (LGM), the Heinrich event 1 and the Younger Dryas/Antarctic Cold Reversal. (ii) Further south and west, precipitation decreases and glaciers therefore become more precipitation sensitive. Maximum or at least prominent glacial advances as far south as 30° S are dated into the Lateglacial, i.e. synchronous with lake transgression phases (Tauca: 14–18 ka, and Coipasa: 11–13 ka). (iii) Between ∼30 and 40° S, glaciers reached their maximum extent much earlier during the pre‐LGM (∼35–40 ka). This is attributed to a northward shift and/or intensification of the westerlies, whereas conditions during the global LGM were too dry to allow for significant glacial advances. (iv) South of 40°, glaciers become temperature sensitive again and reached their maximum accordingly synchronous to the global LGM. Copyright © 2008 John Wiley & Sons, Ltd.
Glacial dynamics in southernmost South America during Marine Isotope Stage 5e to the Younger Dryas chron: a brief review with a focus on cosmogenic nuclide measurements
Authors: Kaplan Michael R. , Moreno Patricio I. , Rojas Maisa
Published: August 2008

The timing of major glacial changes between Marine Isotope Stage (MIS) 5e and the Younger Dryas chron (YD) in southern South America is reviewed. Focus is placed on studies that use cosmogenic nuclide measurements. However, other dated records and modelling results are also discussed to provide the broader glacial geological context. Limits on the state of glacial geologic knowledge are examined and suggestions are made as to how some of these can be addressed in future studies. Studies show that on the east side of the Andes at Lago Buenos Aires (45° S) there is evidence indicating that following a MIS 6 glaciation ice was less extensive during MIS 4 than MIS 2. In contrast, on the west side of the Andes in the Chilean Lake District area, MIS 4 ice may have been more extensive than during MIS 2. Although Patagonia experienced an MIS 2 glaciation broadly in phase with that in other areas around the globe, there are differences in glacial histories between areas on millennial timescales. Climate reversals are evident in many records between ca. 17 and 10 ka. The timing of such Lateglacial activity, which included less extensive advances than during the local Last Glacial Maximum (LGM), varies somewhat between areas. This could be due to the relative influence of middle‐ to high‐latitude climatic regimes. At present, chronological uncertainties prevent confident assignment of cosmogenic ages for glacial events at the millennial timescale and defining associated climate variability between different study areas. Copyright © 2008 John Wiley & Sons, Ltd.
Raman spectroscopic study of the selenite mineral: ahlfeldite, NiSeO3·2H2O
Authors: Frost Ray L. , Keeffe Eloise C.
Published: August 2008

Raman spectroscopy has been used to study the selenite mineral ahlfeldite. A comparison is made with the Raman spectra of chalcomenite, cobaltomenite and clinochalcomenite. Selenite minerals are characterised by the position of the symmetric stretching mode which is observed at higher wavenumbers than the anti‐symmetric stretching mode. The selenite ion has C3v symmetry and four modes, 2A1 and 2E. These modes are observed at 813, 472 cm−1 (A1) and 685, 710, 727 and 367 and 396 cm−1 (E). Bands assigned to the water stretching vibrations are observed for ahlfeldite at 3385 cm−1, for chalcomenite at 2953, 3184 and 3506 cm−1 and for clinochalcomenite at 2909, 3193 and 3507 cm−1. A comparison of the Raman spectra of chalcomenite, clinochalcomenite and cobaltomenite is made. The position of these bands enabled hydrogen bond distances in the selenite structure to be estimated. Hydrogen bond distances for ahlfeldite, chalcomenite and clinochalcomenite were determined to be similar. Copyright © 2008 John Wiley & Sons, Ltd.
Preparation and SERS study of triangular silver nanoparticle self‐assembled films
Authors: Zeng Jianbo , Jia Huiying , An Jing , Han Xiaoxia , Xu Weiqing , Zhao Bing , Ozaki Yukihiro
Published: August 2008

We report a novel type of self‐assembly of triangular silver nanoparticles onto a quartzose substrate with a monolayer of poly(diallyldimethylammonium chloride). Attractive electrostatic interactions between the negatively charged nanoparticles and the positively charged polyelectrolyte are responsible for the self‐assembly. Surface morphology and optical properties of the triangular, silver nanoparticle self‐assembly film were studied by atomic force microscopy (AFM) and ultraviolet–visible (UV–vis) spectroscopy, and then compared with those of the spherical silver nanoparticle self‐assembly film. It was found from the AFM measurement that most of the spherical and triangular silver nanoparticles were assembled directly onto the substrate rather than aggregated to each other. The UV–vis spectrum of the triangular, silver nanoparticle self‐assembled film is quite different from that of the colloid of silver nanoparticles. A peak at 697 nm assigned to the in‐plane dipole plasmon resonance shows a blue shift by 55 nm after the triangular silver nanoparticles are immobilized onto the substrate. The triangular, silver nanoparticle self‐assembly film can be used as a surface‐enhanced Raman scattering (SERS) substrate, and Rhodamine 6G as a Raman probe to evaluate its enhancement ability. It was found that the enhancement ability of the triangular, silver nanoparticle film is remarkable but somewhat lower than that of the spherical silver nanoparticle film. The reason for this is discussed from the point of electromagnetic mechanism and chemical mechanism. Copyright © 2008 John Wiley & Sons, Ltd.
Kunststoffschweißen mit dem Laser
Authors: Hänsch Dirk , Salein Caroline
Published: August 2008

Immer noch wird das Kunststoffschweißen mit dem Laserstrahl als neues, innovatives Fügekonzept deklariert. Doch so jung ist diese Technologie nicht mehr. Seit nunmehr zehn Jahren findet der Laserstrahl Anwendung in der industriellen Serienproduktion, hat sich sowohl in Klein‐ als auch in Großserien bewährt und etabliert. Aufgrund seiner technologischen und wirtschaftlichen Vorteile läst das Verfahren nach und nach die herkömmlichen Verbindungsmethoden für Kunststoffe ab und erobert neue Anwendungsbereiche.
Laserdurchstrahlschweißen von Thermoplasten
Authors: Roesner Andreas , Boglea Andrei , Olowinsky Alexander
Published: August 2008

Dank seiner Vorteile hat sich das Laserschweißen von Kunststoffen zu einem etablierten Fügeverfahren entwickelt und es ersetzt mehr und mehr die bisher üblichen Fügeverfahren. Neue Entwicklungen beim Laserdurchstrahlschweißen ermöglichen nun das Überschreiten bisheriger Grenzen und eröffnen diesem Schweißverfahren weitere Anwendungsfelder.
Neue Halbleiterlaser‐Wellenlängen für das Kunststoffschweißen
Authors: Neukum Jörg
Published: August 2008

Mittlerweile finden sich viele Hochleistungs‐Diodenlaser‐Systeme im industriellen Einsatz, meist jedoch bei Standardwellenlängen zwischen 808 und 980nm. Im Leistungsbereich bis einige hundert Watt sind dies meist thermische Anwendungen im Bereich des Lötens und des Kunststoffschweißens. In Kombination mit Galvo‐Scannern und Pyrometern sind hierbei sowohl geregelte, als auch selektive Prozesse mit Qualitätsdokumentation möglich. Halbleiter‐Laserdioden mit Wellenlängen im Bereich von 1,4 bis 2 μm eröffnen neue Anwendungen in der Materialbearbeitung – insbesondere beim Kunststoffschweißen.
Maskenschweißen von Thermoplasten mittels Laserstrahlung
Authors: Thielen Carsten
Published: August 2008

Viele Innovationen entstehen durch Kundenanforderungen. Oft werden diese Anforderungen durch den Stand der Technik limitiert. Beim Maskenschweißen von Thermoplasten behinderte viele Jahre die optische Leistung der Diodenlaser die Entwicklung des schnellen Verschweißens von kleinen Nähten und großen Strukturen für die Mikrotechnik und Fluidik. Die jetzt erreichten Leistungsklassen haben diese Limitierung für das Maskenschweißen aufgehoben, finden verstärkt Anwendung in der Industrie und treiben weitere Innovationen wie das High Speed Welding in den Markt.
Picosecond Micromachining Update
Authors: Dorman Chris , Schulze Matthias
Published: August 2008

Many industries currently use lasers for drilling, cutting, scribing and contouring materials as diverse as silicon, metals and plastics, with features as small as a few tens of microns. Traditionally, this precision micromachining has been powered by DPSS (diode pumped solid state) or excimer lasers with nanosecond pulse durations, but there is a growing need for even higher precision and resolution. While shorter pulsewidths can yield higher resolution, superior edge quality, and eliminate peripheral thermal effects, drawbacks in existing ultrafast laser technology have limited its use to a few specialty applications. In this article we describe a new type of laser that delivers picosecond output, and combines the simplicity of a fiber laser with the high pulse energy characteristics of a freespace laser. We then discuss applications that can benefit from the unique output, including microelectronics and photovoltaic manufacturing.
Grundlagen der Faserkopplung von Diodenlasern
Authors: Wolf Jürgen , Werner Ekkehard
Published: August 2008

Hochleistungsdiodenlaser werden als Einzelemitter, Laserbarren und Stacks hergestellt. Die Anwendungen, wie zum Beispiel das Pumpen von Faserlasern, erfordern oft eine hohe Strahlqualität, die sich durch Einkopplung des Laserlichts in eine Faser erreichen lässt. In diesem Beitrag werden unterschiedliche Konzepte für Faserkopplungen dieser Lasertypen vorgestellt. Die Palette der darauf basierenden Produkte umfasst Faserdurchmesser von 50 bis 600 μm und Ausgangsleistungen bis zu 600 Watt.
Selective Laser Melting
Authors: Wiesner Andreas
Published: August 2008

Mithilfe der Strahlschmelztechnologie lassen sich räumliche Strukturen Schicht für Schicht aus einem pulverförmigen metallischen Ausgangsstoff herstellen. Dabei wird die Energie eines Strahls vom Pulver absorbiert und führt zu einem lokal begrenztem Verschmelzen von Partikeln. Nahezu jede dreidimensionale Form lässt sich auf diese Weise direkt aus Konstruktionsdaten herstellen. Eine Verfahrensvariante, die im Folgenden näher betrachtet wird, ist das Selektive Laser Melting (SLM).
Minimizing superficial thermal injury using bilateral cryogen spray cooling during laser reshaping of composite cartilage grafts
Authors: Chang Cheng‐Jen , Cheng Sally M.H. , Chiu Lynn L. , Wong Brian J.F. , Ting Keen
Published: August 2008

Composite cartilage grafts were excised from New Zealand rabbit ears. Flat composite grafts (of cartilage and overlying skin graft on both surfaces) were obtained from each ear and cut into a rectangle measuring 50 mm by 25 mm (x by y) with an average thickness of approximately 1.3 mm (z), skin included. Specimens were manually deformed with a jig and maintained in this new position during laser illumination. The composite cartilage grafts were illuminated on the concave surface with an Nd:YAG laser (1,064 nm, 3 mm spot) at 10 W, 20 W, 30 W, 40 W, 50 W. Cryogen spray cooling (CSC) was applied to both exterior (convex) and interior (concave) surfaces of the tissue to reduce thermal injury to the grafts. CSC was delivered: (1) in controlled applications (cryogen released when surface reached 40°C, and (2) receiving only laser at above wattage, no CSC [representing the control group]. The specimens were maintained in a deformation for 15 minutes after illumination and serially examined for 14 days. The control group with no CSC caused injury to all specimens, ranging from minor to full thickness epidermal thermal injury. Although most levels of laser and CSC yielded a high degree of reshaping over an acute time period, after 14 days specimens exposed to 30 W, 40 W, 50 W retained shape better than those treated at 10 W and 20 W. The specimens exposed to 50 W with controlled CSC retained its new shape to the highest degree over all others, and thermal injury was minimal. In conclusion, combinations of laser and CSC parameters were effective and practical for the reshaping of composite cartilage grafts. Lesers Surg. Med. 40:477–482, 2008. © 2008 Wiley‐Liss, Inc.
In vivo nonmelanoma skin cancer diagnosis using Raman microspectroscopy
Authors: Lieber Chad A. , Majumder Shovan K. , Ellis Darrel L. , Billheimer D. Dean , Mahadevan‐Jansen Anita
Published: August 2008

Background and Objectives

Nonmelanoma skin cancers, including basal cell carcinoma (BCC) and squamous cell carcinoma (SCC), are the most common skin cancers, presenting nearly as many cases as all other cancers combined. The current gold‐standard for clinical diagnosis of these lesions is histopathologic examination, an invasive, time‐consuming procedure. There is thus considerable interest in developing a real‐time, automated, noninvasive tool for nonmelanoma skin cancer diagnosis. In this study, we explored the capability of Raman microspectroscopy to provide differential diagnosis of BCC, SCC, inflamed scar tissue, and normal tissue in vivo.

Study Design

Based on the results of previous in vitro studies, we developed a portable confocal Raman system with a handheld probe for clinical study. Using this portable system, we measured Raman spectra of 21 suspected nonmelanoma skin cancers in 19 patients with matched normal skin spectra. These spectra were input into nonlinear diagnostic algorithms to predict pathological designation.

Results

All of the BCC (9/9), SCC (4/4), and inflamed scar tissues (8/8) were correctly predicted by the diagnostic algorithm, and 19 out of 21 normal tissues were correctly classified. This translates into a 100% (21/21) sensitivity and 91% (19/21) specificity for abnormality, with a 95% (40/42) overall classification accuracy.

Conclusions

These findings reveal Raman microspectroscopy to be a viable tool for real‐time diagnosis and guidance of nonmelanoma skin cancer resection. Lesers Surg. Med. 40:461–467, 2008. © 2008 Wiley‐Liss, Inc.
Anti‐Inflammatory effects of low‐level laser therapy (660 nm) in the early phase in carrageenan‐induced pleurisy in rat
Authors: Boschi Emerson S. , Leite Carlos E. , Saciura Vasyl C. , Caberlon Eduardo , Lunardelli Adroaldo , Bitencourt Shanna , Melo Denizar A.S. , Oliveira Jarbas R.
Published: August 2008

Background and Objective

In the classic model of pleurisy there is little evidence about the anti‐inflammatory effects of low‐level laser therapy (LLLT) as well the dosage characteristics, such as wavelength, total energy, number and pattern of treatment. In this study we investigated the potential effects of LLLT on modulating the pro‐inflammatory and anti‐inflammatory mediators of acute inflammation in a rat pleurisy model.

Study Design/Materials and Methods

A sample of 48 female Wistar rats were divided into control and experiential groups. An inflammation was induced by carrageenan (0.2 ml) injected into the pleural cavity. At 1, 2, and 3 hours after induction a continuous wave (20 mW) diode laser of the InGaAlP (660 nm) type was used in the four laser groups with different doses and treatment patterns. One group received a single dose of 2.1 J and the other three groups received a total energy of 0.9, 2.1, and 4.2 J. Four hours later the exudate volume, total and differential leukocytes, protein concentration, NO, IL‐6, IL‐10, TNF‐α, and MCP‐1 were measured from the aspirated liquid.

Results

All the treatment patterns and quantity of energy studied show significant reduction of the exudate volume (P<0.05). Using energy of 0.9 J only NO, IL‐6, MCP‐1 and IL‐10 are significantly reduced (P<0.05). On the other hand, higher energies (2.1 and 4.2 J) significantly reduce all variables independently of the treatment pattern. The neutrophil migration has a straight correlation with the TNF‐α (r = 0.551) and NO (r = 0.549) concentration.

Conclusions

LLLT—660 nm induced an anti‐inflammatory effect characterized by inhibition of either total or differential leukocyte influx, exudation, total protein, NO, IL‐6, MCP‐1, IL‐10, and TNF‐α, in a dose‐dependent manner. Under these conditions, laser treatment with 2.1 J was more effective than 0.9 and 4.2 J. Lesers Surg. Med. 40:500–508, 2008. © 2008 Wiley‐Liss, Inc.
Unipolar versus bipolar radiofrequency treatment of rhytides and laxity using a mobile painless delivery method
Authors: Alexiades‐Armenakas Macrene , Dover Jeffrey S. , Arndt Kenneth A.
Published: August 2008

Background

Previous studies have shown that radiofrequency (RF) energy is a safe and effective treatment for rhytide‐reduction.

Objective

This randomized, blinded, split‐face study assesses the safety and efficacy of the unipolar versus bipolar handpieces on an RF device with a mobile delivery method for the treatment of rhytides and laxity using quantitative grading.

Methods

In this randomized, blinded, split‐face design study, 10 subjects (aged 18–75 years) with a clinically observable excess of rhytides and laxity (minimum grade 2 out of 4) on the face received four treatments at 1‐week intervals with random assignment of unipolar RF to one side and bipolar RF to the contralateral side. Each side received approximately four passes per treatment delivered in a mobile continuous manner. Results were evaluated by two blinded investigators of photographs employing a comprehensive 4‐point grading scale at baseline, and 1‐ and 3‐month follow‐up visits after the final treatment.

Results

All subjects completed and responded to treatment. The blinded evaluations demonstrated the following mean percent improvements in grading scores of rhytides and laxity: for the unipolar side 6.0±4.6% and 4.6±4.8% versus the bipolar side 4.4±2.5 and 7.3±3.5%. The degree of improvement approached but did not achieve statistical significance for either handpiece, but demonstrated a trend toward improvement (P = 0.5599 unipolar vs. 0.1108 bipolar). The treatment was painless (rated 0 out of 10 by all subjects) and side effects included minimal erythema which resolved within 1–3 hours. No crusting, dyspigmentation or scarring was observed.

Conclusion

This randomized, split‐face study with blinded evaluations employing a quantitative grading scale demonstrated that minimal pass, mobile energy delivery serial treatments with either the unipolar or bipolar handpieces of a novel RF device appears to safe and painless. Each handpiece demonstrated minimal clinical efficacy which was not statistically significant, but with a trend toward improvement in rhytides and laxity of facial skin. Lesers Surg. Med. 40:446–453, 2008. © 2008 Wiley‐Liss, Inc.
Highly Conductive Core–Shell Nanocomposite of Poly(N‐vinylcarbazole)–Polypyrrole with Multiwalled Carbon Nanotubes
Authors: Maity Arjun , Sinha Ray Suprakas
Published: August 2008

In this communication, the synthesis, characterization, and properties of highly conductive core–shell nanocomposites of poly(N‐vinylcarbazole) (PNVC)–polypyrrole (PPY) copolymers with multi‐walled carbon nanotubes (MWCNTs) are described. A unique free‐radical coupling reaction between PNVC and PPY cation radicals in chloroform solvent, using feric chloride as an oxidant, in the presence of suspended MWCNTs in the reaction medium, was used for the synthesis of nanocomposite. Field‐emission scanning and transmission electron microscopy studies showed the formation of the core–shell nanocomposite. Raman spectrocopy results as well as thermogravimetric analysis supported the electron microscopic observations. The resulting PNVC–PPY copolymer‐coated MWCNTs showed an unprecedentedly increased value of direct electrical conductivity (bulk) compared to the conductivity of all samples even with pure MWCNTs.

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Macromol. Rapid Commun. 17/2008
Authors: Wagner Nicole L. , Timmers Francis J. , Arriola Daniel J. , Jueptner Guenter , Landes Brian G.
Published: August 2008

Front Cover: The cover picture is an artistic representation of a random blocky copolymer of polyethylene and polycarbonate prepared using segment interchange metathesis superimposed onto the resulting TEM. The chemically distinct polymer segments of the blocky copolymer spontaneously self‐assemble into microphase structures, which persist into the melt state. Further details can be found in the article by N. L. Wagner,* F. J. Timmers, D. J. Arriola, G. Jueptner, and B. G. Landes on page 1438.
Apigenin suppresses insulin‐like growth factor I receptor signaling in human prostate cancer: An in vitro and in vivo study
Authors: Shukla Sanjeev , Gupta Sanjay
Published: August 2008

Deregulation of insulin‐like growth factor (IGF)‐I/IGF‐IR signaling has been implicated in the development and progression of prostate cancer. Agents that can suppress the mitogenic activity of the IGF/IGF‐IR growth axis may be of preventive or therapeutic value. We have previously demonstrated that apigenin, a plant flavone, modulates IGF signaling through upregulation of IGFBP‐3. In this study, we investigated the mechanism(s) of apigenin action on the IGF/IGF‐IR signaling pathway. Exposure of human prostate cancer DU145 cells to apigenin markedly reduced IGF‐I‐stimulated cell proliferation and induced apoptosis. Apigenin inhibited IGF‐I‐induced activation of IGF‐IR and Akt in DU145 cells. Similar growth inhibitory and apoptotic responses were observed in PC‐3 cells, which constitutively overexpress this pathway. This effect of apigenin appears to be due partially to reduced autophosphorylation of IGF‐IR. Inhibition of p‐Akt by apigenin resulted in decreased phosphorylation of GSK‐3β along with decreased expression of cyclin D1 and increased expression of p27/kip1. In vivo administration of apigenin to PC‐3 tumor xenografts inhibited tumor growth, resulted in IGF‐IR inactivation and dephosphorylation of Akt and its downstream signaling. These results suggest that inhibition of cell proliferation and induction of apoptosis by apigenin are mediated, at least in part, by its ability to inhibit IGF/IGF‐IR signaling and the PI3K/Akt pathway. © 2008 Wiley‐Liss, Inc.
High spectral and spatial resolution MRI of age‐related changes in murine prostate
Authors: Foxley Sean , Fan Xiaobing , Jansen Sanaz A. , Zamora Marta , Markiewicz Erica , Al‐Ahmadie Hikmat , Karczmar Gregory S.
Published: August 2008

The purpose of this work was to evaluate high‐resolution echo‐planar spectroscopic MRI of normal and precancerous prostatic changes in a transgenic mouse line. Simian virus large T‐antigen transgenic male mice (N = 7, age = 34 ± 3.7 weeks) with prostatic hyperplasia and intraepithelial neoplasia (PIN) were studied. High spectral and spatial resolution (HiSS) MRI of the water proton signal was compared to the free induction decay (FID) integral image and conventional gradient‐echo and spin‐echo imaging. Water peak‐height images of the prostate produced from HiSS datasets showed improved contrast‐to‐noise ratio (CNR) (P < 0.03), and greater morphological detail (P < 0.004) based on texture analysis. Despite the high spectral resolution of the HiSS datasets, signal‐to‐noise ratio (SNR) compared favorably with that of the FID integral and conventional images. Lobular features in HiSS images of older mice were consistent with hyperplasia seen on histology. A partially deuterated water‐filled catheter was inserted in the mouse rectum for susceptibility matching between the colon interior and exterior to minimize image artifacts. These preliminary results suggest that HiSS MRI provides detailed morphology of the murine prostate and can detect early changes associated with the development of cancer. HiSS MRI of patients may have similar advantages. Magn Reson Med 60:575–581, 2008. © 2008 Wiley‐Liss, Inc.
Tracking the effects of crusher gradients on gradient‐echo BOLD signal in space and time during rat sensory stimulation
Authors: Goelman Gadi , Pelled Galit , Dodd Steve , Koretsky Alan
Published: August 2008

A unique method to map the effect of crusher gradients in space and time on the gradient echo blood oxygen level dependent (BOLD) signal is introduced. Using the Radial Correlation Contrast (RCC) analysis method, amplitude‐RCC maps at different time segments and different gradient strengths were obtained. The ratio of amplitude‐RCC cluster volumes, with and without crusher gradients, showed a temporal dependency with stronger volume reduction for stimulation‐onset versus stimulation‐decline. Aside from signal‐to‐noise ratio reduction in diffusion weighted images, the average temporal patterns were equal. Comparison of the data with and without crushers showed a stronger reduction in local coherence for stimulation‐onset times. We hypothesize that the stimulation decline was weighted by extravascular effects originating in expanded veins due to their larger volume and long range susceptibility which couples neighboring voxels. The ratio of amplitude‐RCC with and without crushers calculated for each voxel at each time segment yielded a spatial–temporal mapping of the crusher effect. These maps suggest that early stimulation‐onset (∼9 s) is weighted by flow; later a dynamic steady‐state between intra‐ and extravascular effects is obtained. Stimulation‐decline was dominated by extravascular effects, and at late stimulation decline as well as at early stimulation onset, clusters were small and localized to expected site of neuronal activity. Magn Reson Med 60:548–554, 2008. © 2008 Wiley‐Liss, Inc.
Balanced left ventricular myocardial SSFP‐tagging at 1.5T and 3T
Authors: Markl M. , Scherer S. , Frydrychowicz A. , Burger D. , Geibel A. , Hennig J.
Published: August 2008

The purpose of the study was to evaluate the performance of steady‐state free precession (SSFP)‐tagging at 1.5T and 3T and to define the ideal settings with respect to optimized tag contrast throughout the cardiac cycle for both field strengths. To identify optimal imaging parameters data acquisition was repeated for different flip angles. Left ventricular tag‐tissue contrast, tag fading times, tag persistence, and myocardial signal‐to‐noise ratio (SNR) were quantified in basal, mid‐ventricular, and apical slice locations. To assess the effect of field strength on image quality and artifact level, additional semiquantitative image grading was performed by two experienced readers. SSFP‐tagging at 3T proved superior to 1.5T and provided significantly enhanced tag persistence and myocardial SNR while maintaining overall image quality and artifact level. The definition of a tag quality index demonstrated optimal SSFP‐tagging performance for a flip angle of 20°. Diastolic tag visibility was improved at 3T and resulted in enhanced average tag persistence of 789 ± 128 ms compared to 523 ± 40 ms at 1.5T. For SSFP‐tagging at 3T the combination of T1 lengthening and superior myocardial SNR is highly promising and has the potential to improve the depiction of tagged myocardial function throughout the entire cardiac cycle. Magn Reson Med 60:631–639, 2008. © 2008 Wiley‐Liss, Inc.
3D high temporal and spatial resolution contrast‐enhanced MR angiography of the whole brain
Authors: Haider Clifton R. , Hu Houchun Harry , Campeau Norbert G. , Huston John , Riederer Stephen J.
Published: August 2008

Sensitivity encoding (SENSE) and partial Fourier techniques have been shown to reduce the acquisition time and provide high diagnostic quality images. However, for time‐resolved acquisitions there is a need for both high temporal and spatial resolution. View sharing can be used to provide an increased frame rate but at the cost of acquiring spatial frequencies over a duration longer than a frame time. In this work we hypothesize that a CArtesian Projection Reconstruction‐like (CAPR) technique in combination with 2D SENSE, partial Fourier, and view sharing can provide 1–2 mm isotropic resolution with sufficient temporal resolution to distinguish intracranial arterial and venous phases of contrast passage in whole‐brain angiography. In doing so, the parameter of “temporal footprint” is introduced as a descriptor for characterizing and comparing time‐resolved view‐shared pulse sequences. It is further hypothesized that short temporal footprint sequences have higher temporal fidelity than similar sequences with longer temporal footprints. The tradeoff of temporal footprint and temporal acceleration is presented and characterized in numerical simulations. Results from 11 whole‐brain contrast‐enhanced MR angiography studies with the new method with SENSE acceleration factors R = 4 and 5.3 are shown to provide images of comparable or higher diagnostic quality than the unaccelerated reference. Magn Reson Med 60:749–760, 2008. © 2008 Wiley‐Liss, Inc.
Novel MRI method to detect altered left ventricular ejection and filling patterns in rodent models of disease
Authors: Stuckey Daniel J. , Carr Carolyn A. , Tyler Damian J. , Aasum Ellen , Clarke Kieran
Published: August 2008

The aim of this study was to determine whether high‐temporal‐resolution (HTR) cardiac cine‐MRI could be used to identify subtle alterations in contractility and diastolic function in rodent models of disease. Following standard 45‐min in vivo MRI measurements of left ventricular (LV) volumes, a single mid‐ventricular slice was selected for 3‐min HTR imaging. Cavity volume was measured every 2.4 ms, yielding approximately 60 images through the cardiac cycle. From these images, peak ejection and filling rates were calculated and two separate filling phases (comparable with the early (E) and late (A) phases of a Doppler echocardiogram) were identified during diastole. Repeated HTR imaging of the same animals on sequential days indicated reproducibility of E′/A′ ratios of 11%. In chronically infarcted rat hearts, HTR imaging revealed lower peak ejection rates (PERs), peak early filling rates (E′) and E′/A′ ratios, and higher peak late filling rates (A′) than in sham‐operated rats. Diabetic db/db mouse hearts had the same function as controls when using standard cine‐MRI, yet HTR imaging identified significantly lower PERs, early filling rates and E′/A′ ratios in diabetic mouse hearts. In conclusion, the HTR MRI technique revealed changes in function that were below the limits of detection of standard cine‐MRI. Magn Reson Med 60:582–587, 2008. © 2008 Wiley‐Liss, Inc.
Comparison of parallel MRI reconstruction methods for accelerated 3D fast spin‐echo imaging
Authors: Xiao Zhikui , Hoge W. Scott , Mulkern R.V. , Zhao Lei , Hu Guangshu , Kyriakos Walid E.
Published: August 2008

Parallel MRI (pMRI) achieves imaging acceleration by partially substituting gradient‐encoding steps with spatial information contained in the component coils of the acquisition array. Variable‐density subsampling in pMRI was previously shown to yield improved two‐dimensional (2D) imaging in comparison to uniform subsampling, but has yet to be used routinely in clinical practice. In an effort to reduce acquisition time for 3D fast spin‐echo (3D‐FSE) sequences, this work explores a specific nonuniform sampling scheme for 3D imaging, subsampling along two phase‐encoding (PE) directions on a rectilinear grid. We use two reconstruction methods—2D‐GRAPPA‐Operator and 2D‐SPACE RIP—and present a comparison between them. We show that high‐quality images can be reconstructed using both techniques. To evaluate the proposed sampling method and reconstruction schemes, results via simulation, phantom study, and in vivo 3D human data are shown. We find that fewer artifacts can be seen in the 2D‐SPACE RIP reconstructions than in 2D‐GRAPPA‐Operator reconstructions, with comparable reconstruction times. Magn Reson Med 60:650–660, 2008. © 2008 Wiley‐Liss, Inc.
Effects of refocusing flip angle modulation and view ordering in 3D fast spin echo
Authors: Busse Reed F. , Brau Anja C.S. , Vu Anthony , Michelich Charles R. , Bayram Ersin , Kijowski Richard , Reeder Scott B. , Rowley Howard A.
Published: August 2008

Recent advances have reduced scan time in three‐dimensional fast spin echo (3D‐FSE) imaging, including very long echo trains through refocusing flip angle (FA) modulation and 2D‐accelerated parallel imaging. This work describes a method to modulate refocusing FAs that produces sharp point spread functions (PSFs) from very long echo trains while exercising direct control over minimum, center‐k‐space, and maximum FAs in order to accommodate the presence of flow and motion, SNR requirements, and RF power limits. Additionally, a new method for ordering views to map signal modulation from the echo train into ky‐kz space that enables nonrectangular k‐space grids and autocalibrating 2D‐accelerated parallel imaging is presented. With long echo trains and fewer echoes required to encode large matrices, large volumes with high in‐ and through‐plane resolution matrices may be acquired with scan times of 3–6 min, as demonstrated for volumetric brain, knee, and kidney imaging. Magn Reson Med 60:640–649, 2008. © 2008 Wiley‐Liss, Inc.
Sources of hepatic glucose production by 2H2O ingestion and Bayesian analysis of 2H glucuronide enrichment
Authors: Delgado T.C. , Barosa C. , Castro M.M.C.A. , Geraldes C.F.G.C. , Bastos M. , Baptista C. , Fagulha A. , Barros L. , Mota A. , Carvalheiro M. , Jones J.G. , Merritt Matthew
Published: August 2008

The contribution of gluconeogenesis to hepatic glucose production (GP) was quantified after 2H2O ingestion by Bayesian analysis of the position 2 and 5 2H‐NMR signals (H2 and H5) of monoacetone glucose (MAG) derived from urinary acetaminophen glucuronide. Six controls and 10 kidney transplant (KTx) patients with cyclosporine A (CsA) immunosuppressant therapy were studied. Seven KTx patients were lean and euglycemic (BMI = 24.3 ± 1.0 kg/m2; fasting glucose = 4.7 ± 0.1 mM) while three were obese and hyperglycemic (BMI = 30.5 ± 0.7 kg/m2; fasting glucose = 7.1 ± 0.5 mM). For the 16 spectra analyzed, the mean coefficient of variation for the gluconeogenesis contribution was 10% ± 5%. This uncertainty was associated with a mean signal‐to‐noise ratio (SNR) of 79:1 and 45:1 for the MAG H2 and H5 signals, respectively. For control subjects, gluconeogenesis contributed 54% ± 7% of GP as determined by the mean and standard deviation (SD) of individual Bayesian analyses. For the lean/normoglycemic KTx subjects, the gluconeogenic contribution to GP was 62% ± 7% (P = 0.06 vs. controls), while hyperglycemic/obese KTx patients had a gluconeogenic contribution of 68% ± 3% (P < 0.005 vs. controls). These data suggest that in KTx patients, an increased gluconeogenic contribution to GP is strongly associated with obesity and hyperglycemia. Magn Reson Med 60:517–523, 2008. © 2008 Wiley‐Liss, Inc.
Voxel‐shift and interpolation for hadamard‐encoded MR images
Authors: Fleysher Lazar , Fleysher Roman , Liu Songtao , Gonen Oded
Published: August 2008

Although Fourier gradient phase‐encoding and Hadamard radio‐frequency encoding are two established spatial MR localization techniques, the absence of voxel‐shift and interpolation postprocessing algorithms for the latter has always placed it at a discouraging disadvantage. This article presents a method for voxel‐shift and interpolation of Hadamard‐encoded data and demonstrates both theoretically and experimentally the similarities of the respective operations between the two localization methods. Magn Reson Med 60:524–535, 2008. © 2008 Wiley‐Liss, Inc.
Modeling SSFP functional MRI contrast in the brain
Authors: Miller Karla L. , Jezzard Peter
Published: August 2008

Steady‐state free precession (SSFP) has recently been proposed for function MRI because of the potential for reducing image distortion and signal dropout. Several different contrast mechanisms have been suggested to explain the reported observations, but there has been limited work comparing theory with experiment in the brain. Moreover, the detailed work that has considered oxygen‐dependent signal in SSFP outside the brain has focused on R2 effects in the pass band, and largely neglected the signal contrast that occurs due to off‐resonance effects. The article describes a model for SSFP functional contrast based on the convolution of the theoretical SSFP profile with the underlying frequency distribution. It is demonstrated that such a model must account for the effects of diffusion, which can alter the apparent R2 and linespread. Monte Carlo simulations are used to calibrate corrections for these terms. This new model has the computational efficiency of the convolution model while encapsulating information from more time‐consuming Monte Carlo simulations. This corrected convolution model is shown to agree well with experimental data, and model predictions and limitations are discussed. Magn Reson Med 60:661–673, 2008. © 2008 Wiley‐Liss, Inc.