bluuebunny/crossref_metadata_2025 huggingface dataset:
Imaging strategies to reduce the risk of radiation in CT studies, including selective substitution with MRI
Authors: Semelka Richard C. , Armao Diane M. , Elias Jorge , Huda Walter
Published: April 2007

“When one admits that nothing is certain one must, I think, also admit that some things are much more nearly certain than others.” Bertrand Russell (1872–1970)

Computed tomography (CT) is one of the largest contributors to man‐made radiation doses in medical populations. CT currently accounts for over 60 million examinations in the United States, and its use continues to grow rapidly. The principal concern regarding radiation exposure is that the subject may develop malignancies. For this systematic review we searched journal publications in MEDLINE (1966–2006) using the terms “CT,” “ionizing radiation,” “cancer risks,” “MRI,” and “patient safety.” We also searched major reports issued from governmental U.S. and world health‐related agencies. Many studies have shown that organ doses associated with routine diagnostic CT scans are similar to the low‐dose range of radiation received by atomic‐bomb survivors. The FDA estimates that a CT examination with an effective dose of 10 mSv may be associated with an increased chance of developing fatal cancer for approximately one patient in 2000, whereas the BEIR VII lifetime risk model predicts that with the same low‐dose radiation, approximately one individual in 1000 will develop cancer. There are uncertainties in the current radiation risk estimates, especially at the lower dose levels encountered in CT. To address what should be done to ensure patient safety, in this review we discuss the “as low as reasonably achievable” (ALARA) principle, and the use of MRI as an alternative to CT. J. Magn. Reson. Imaging 2007;25:900–909. © 2007 Wiley‐Liss, Inc.
Patient motion correction for multiplanar, multi‐breath‐hold cardiac cine MR imaging
Authors: Slomka Piotr J. , Fieno David , Ramesh Amit , Goyal Vaibhav , Nishina Hidetaka , Thompson Louise E.J. , Saouaf Rola , Berman Daniel S. , Germano Guido
Published: April 2007

Purpose

To correct for spatial misregistration of multi‐breath‐hold short‐axis (SA), two‐chamber (2CH), and four‐chamber (4CH) cine cardiac MR (CMR) images caused by respiratory and patient motion.

Materials and Methods

Twenty CMR studies from consecutive patients with separate breath‐hold 2CH, 4CH, and SA 20‐phase cine images were considered. We automatically registered the 2CH, 4CH, and SA images in three dimensions by minimizing the cost function derived from plane intersections for all cine phases. The automatic alignment was compared with manual alignment by two observers.

Results

The processing time for the proposed method was <20 seconds, compared to 14–24 minutes for the manual correction. The initial plane displacement identified by the observers was 2.8 ± 1.8 mm (maximum = 14 mm). A displacement of ≥5 mm was identified in 15 of 20 studies. The registration accuracy (defined as the difference between the automatic parameters and those obtained by visual registration) was 1.0 ± 0.9 mm, 1.1 ± 1.0 mm, 1.1 ± 1.2 mm, and 2.0 ± 1.8 mm for 2CH‐4CH alignment and SA alignment in the mid, basal, and apical regions, respectively. The algorithm variability was higher in the apex (2.0 ± 1.9 mm) than in the mid (1.4 ± 1.4 mm) or basal (1.2 ± 1.2 mm) regions (ANOVA, P < 0.05).

Conclusion

An automated preprocessing algorithm can reduce spatial misregistration between multiple CMR images acquired at different breath‐holds and plane orientations. J. Magn. Reson. Imaging 2007;25:965–973. © 2007 Wiley‐Liss, Inc.
A simple catheter‐vessel model for MR assessment of drug distribution in arteries and optimization of catheter design for intraarterial infusion therapy
Authors: Yoshikawa Takeshi , Uchida Koji , Ohno Yoshiharu , Hirota Shozo , Nakamura Tomonori , Yoshizako Takeshi , Ishida Jun , Kitagaki Hajime
Published: April 2007

Purpose

To investigate the efficacy of a new catheter‐vessel model for MRI to evaluate drug distribution and to optimize catheter design for intraarterial infusion therapy

Materials and Methods

The model consisted of a hepatic artery simulant tube through which blood simulant water flowed continuously and a water cistern. Catheters were inserted into the tube and a gadolinium contrast medium was injected at rates suitable for angiographic or computed tomographic evaluation and commensurate with the clinical drug infusion rate. Axial images of the tube were obtained with a 0.2‐T scanner and gradient echo technique. Preliminary studies and catheter tests were conducted. The points at which drug and water were completely mixed were defined as the site with uniform enhancement nearest the catheter tip.

Results

Flip angle and gadolinium concentrations were optimized at 90 degrees, and at 62.5 and 500 mM for the high and low infusion rates, respectively. Drug distribution near the catheter tips was clearly visualized. The drug was mixed in shorter distances via the slit side‐hole than the end‐ or side‐hole catheters, and the smaller diametrical than the larger at either rate.

Conclusion

This model appeared to be effective for evaluation of drug distribution and optimization of catheter design. J. Magn. Reson. Imaging 2007;25:1044–1050. © 2007 Wiley‐Liss, Inc.
Prophylactic effects of chitin microparticles on highly pathogenic H5N1 influenza virus
Authors: Ichinohe Takeshi , Nagata Noriyo , Strong Peter , Tamura Shin‐ichi , Takahashi Hidehiro , Ninomiya Ai , Imai Masaki , Odagiri Takato , Tashiro Masato , Sawa Hirofumi , Chiba Joe , Kurata Takeshi , Sata Tetsutaro , Hasegawa Hideki
Published: April 2007

Highly pathogenic avian influenza virus (H5N1) is an emerging pathogen with the potential to cause great harm to humans, and there is concern about the potential for a new influenza pandemic. This virus is resistant to the antiviral effects of interferons and tumor necrosis factor‐α. However, the mechanism of interferon‐independent protective innate immunity is not well understood. The prophylactic effects of chitin microparticles as a stimulator of innate mucosal immunity against a recently obtained strain of H5N1 influenza virus infection were examined in mice. Clinical parameters and the survival rate of mice treated by intranasal application of chitin microparticles were significantly improved compared to non‐treated mice after a lethal influenza virus challenge. Flow cytometric analysis revealed that the number of natural killer cells that expressed tumor necrosis factor‐related apoptosis‐inducing ligand (TRAIL) and that had migrated into the cervical lymph node was markedly increased (26‐fold) after intranasal treatment with chitin microparticles. In addition, the level of IL‐6 and interferon‐gamma‐inducible protein‐10 (IP‐10) in the nasal mucosa after H5N1 influenza virus challenge was decreased by prophylactic treatment with chitin microparticles. These results suggest that prophylactic intranasal administration of chitin microparticles enhanced the local accumulation of natural killer cells and suppressed hyper‐induction of cytokines, resulting in an innate immune response to prevent pathogenesis of H5N1 influenza virus. J. Med. Virol. 79: 811–819, 2007. © 2007 Wiley‐Liss, Inc.
Molecular characterization of rare G3P[9] rotavirus strains isolated from children hospitalized with acute gastroenteritis
Authors: Khamrin Pattara , Maneekarn Niwat , Peerakome Supatra , Tonusin Supin , Phan Tung Gia , Okitsu Shoko , Ushijima Hiroshi
Published: April 2007

In 2004, an epidemiological survey of human rotavirus infection in Chiang Mai, Thailand detected two uncommon human rotavirus strains (CMH120/04 and CMH134/04) bearing AU‐1‐like G3P[9] genotypes in 1 year old children hospitalized with acute gastroenteritis. The CMH120/04 and CMH134/04 rotavirus strains were characterized by molecular analyses of their VP6, VP7, VP8*, and NSP4 gene segments as well as the determination of RNA patterns by polyacrylamide gel electrophoresis (PAGE). Analysis of the VP8* gene revealed a high level of amino acid sequence identities with those of P[9] rotavirus reference strains, ranging from 94.9% to 98.3%. The highest identities were shared with the human rotavirus AU‐1 strain at 97.8% and 98.3% for CMH120/04 and CMH134/04 strains, respectively. Analysis of the VP7 gene sequence revealed the highest identities with G3 human rotavirus strain KC814 at 96.6% and 96.2% for CMH120/04 and CMH134/04 strains, respectively. Based on the analyses of VP7 and VP8* genes, CMH120/04 and CMH134/04 belonged to G3P[9] genotypes. In addition, analyses of VP6 and NSP4 sequences revealed a VP6 subgroup (SG) I, with NSP4 genetic group C specificities. Moreover, both strains displayed a long RNA electrophoretic pattern. The finding of uncommon G3P[9] rotaviruses in pediatric patients provided additional evidence of the genetic/antigenic diversities of human group A rotaviruses in the Chiang Mai area of Thailand. J. Med. Virol. 79: 843–851, 2007. © 2007 Wiley‐Liss, Inc.
Molecular epidemiology of hepatitis A in St. Petersburg, Russia, 1997–2003
Authors: Davidkin Irja , Zheleznova Nina , Jokinen Sari , Gorchakova Olga , Broman Mia , Mukomolov Sergey
Published: April 2007

The molecular epidemiology of hepatitis A virus (HAV) strains circulating in the St. Petersburg and Karelia regions was studied during 1997–2003. Hepatitis A virus RNA was isolated from both clinical samples (stools or sera) and environmental samples (sewage water). RT‐PCR was carried out using different primer pairs from the VP1/2A and VP1 genomic regions, the variable parts of the HAV genome. PCR products were sequenced and 306 nucleotides from the VP1/2A and 332 nucleotides from the VP1 region were used for phylogenetic analysis. The results show that the IA subtype was the most common during the follow‐up period: >90% of the isolated HAV strains belonged to that subtype. The HAV strains found in intravenous drug users belonged to subtypes IA and IIIA. Only one out of a total of 88 sequenced strains was of the IB subtype. The subtypes IB and IIIA were found only in 2001–2003, which suggests that new strains were introduced into the endemic situation. The results indicate the usefulness of molecular epidemiological methods in studying changes in the circulating HAV strains and in tracing transmission routes. J. Med. Virol. 79: 657–662, 2007. © 2007 Wiley‐Liss, Inc.
Hepatitis B virus genotypes in children and adolescents in Japan: Before and after immunization for the prevention of mother to infant transmission of hepatitis B virus
Authors: Inui Ayano , Komatsu Haruki , Sogo Tsuyoshi , Nagai Toshiro , Abe Kenji , Fujisawa Tomoo
Published: April 2007

The genotype distribution of hepatitis B virus (HBV) was investigated in 118 children in Japan. One hundred and sixteen children (98%) had chronic HBV infection, and the remainder had acute hepatitis. Genotyping of HBV was determined by PCR and sequencing analysis in the S gene. Genotype C (86%) was the most frequent, followed by genotype B (9%), D (2.5%), and A (1.0%). Transmission routes of HBV to children were from mothers in 91 patients (77%), fathers in 8 (6.5%), mother or father in 1 (1%), family members other than the parents in 5 (4%), and unknown in 13 (11.5%). The relationship between routes of HBV transmission and HBV genotypes was studied. Eighty‐eight (97%) of 91 children of mother‐to‐infant transmission were genotype C, while 13 (49%) of 27 children of the routes other than the mother to infant transmission were genotype C. The number of children with genotype C who were infected from their mothers was significantly higher than those with genotype B, D, or A (P < 0.01). In conclusion, HBV genotypes influence not only clinical characteristics but also the mechanisms of inter‐personal HBV transmission. J. Med. Virol. 79: 670–675, 2007. © 2007 Wiley‐Liss, Inc.
Alpha‐7 nicotinic acetylcholine receptor agonists selectively activate limbic regions of the rat forebrain: An effect similar to antipsychotics
Authors: Hansen Henrik H. , Timmermann Daniel B. , Peters Dan , Walters Carrie , Damaj M. Imad , Mikkelsen Jens D.
Published: April 2007

It is considered that activation of nicotinic α7 receptors (α7 nAChR) is useful for the treatment of cognitive disturbances in schizophrenia and Alzheimer's disease. Recently, selective α7 nAChR agonists have been discovered and are used to validate the α7 nAChR as a drug target for the treatment of cognitive disturbances in schizophrenia. One important feature shared by all known antipsychotics is their capacity to induce expression of the neuronal immediate‐early gene c‐fos in the limbic forebrain. Using two novel and selective α7 nAChR agonists, PNU‐282987 and SSR180711, we investigated their ability to induce c‐Fos expression in the limbic forebrain with particular emphasis on the same regions reported to be activated by antipsychotics. Both α7 nAChR agonists increased c‐Fos dose‐dependently in the prefrontal cortex and the shell of nucleus accumbens, while leaving the core of nucleus accumbens and the dorsolateral striatum unaffected. The accumbal and cortical effect of SSR180711 was blocked completely by pre‐administration of the α7 nAChR antagonist methyllycaconitine. Also, SSR180711 displayed no c‐Fos‐inducing effect in α7 nAChR knock‐out mice. In conclusion, these results show that selective pharmacologic stimulation of α7 nAChR function results in activation of forebrain regions similar to conventional antipsychotics. © 2007 Wiley‐Liss, Inc.
Postnatal neurogenesis in hippocampal slice cultures: Early in vitro labeling of neural precursor cells leads to efficient neuronal production
Authors: Namba Takashi , Mochizuki Hideki , Onodera Masafumi , Namiki Hideo , Seki Tatsunori
Published: April 2007

Neurogenesis continues throughout life in the hippocampus. To study postnatal neurogenesis in vitro, hippocampal slices from rats on postnatal day 5 (P5) were cultured on a porous membrane for 14 or 21 days. In the initial experiments, precursor cells were labeled with bromodeoxyuridine (BrdU) after 7 days in culture because hippocampal slices are generally used in experiments after 1–2 weeks in culture. Fourteen days after labeling, however, only about 10% of BrdU‐labeled cells expressed neuronal markers, although in living rats, about 80% of cells labeled with BrdU on P5 had become neurons by P19. Next, rats were injected with BrdU 30 min before culture, after which hippocampal slices were cultured for 14 days to examine the capacity of in vivo–labeled neural precursors to differentiate into neurons in vitro. In this case, more than two‐thirds of BrdU‐labeled cells expressed neuronal markers, such as Hu, NeuN, and PSA‐NCAM. Furthermore, precursor cells underwent early in vitro labeling by incubation with BrdU or a modified retrovirus vector carrying EGFP for 30 min from the beginning of the culture. This procedure resulted in a similar high rate of neuronal differentiation and normal development into granule cells. In addition, time‐lapse imaging with retrovirus‐EGFP revealed migration of neural precursors from the hilus to the granule cell layer. These results indicate that in vivo– and early in vitro–labeled cultures are readily available ex vivo models for studying postnatal neurogenesis and suggest that the capacity of neural precursors to differentiate into neurons is reduced during the culture period. © 2007 Wiley‐Liss, Inc.
Expression of zinc finger transcription factor Bcl11A/Evi9/CTIP1 in rat brain
Authors: Kuo Ting‐Yu , Hsueh Yi‐Ping
Published: April 2007

Bcl11A/Evi9/CTIP1, a Kruppel‐like zinc finger gene, plays an important role in B‐cell development. In addition to expression in B lymphocytes, Bcl11A/Evi9/CTIP1 is also highly expressed in the brain, although its function there is still unclear. In the present study, regional and subcellular distributions of Bcl11A/Evi9/CTIP1 in rat brain were investigated by immunostaining and biochemical fractionation. Using antibodies recognizing the first 18 amino acid residues of Bcl11A/Evi9/CTIP1, the distribution of 2 isoforms of Bcl11A/Evi9/CTIP1 gene products, Bcl11A‐L/Evi9a and Bcl11A‐S/Evi9c, was examined. In rat brain, both Bcl11A‐L/Evi9a and Bcl11A‐S/Evi9c were expressed, although the amount of Bcl11A‐S/Evi9c protein was higher. Bcl11A‐S/Evi9c was widely expressed in different regions of the rat brain. In contrast, Bcl11A‐L/Evi9a was more restricted, being expressed in the cerebral cortex, hippocampus, and olfactory bulb. At the subcellular level, biochemical fractionation and confocal analysis of adult rat brain revealed that, in addition to being in the nuclei of neurons, fractions of Bcl11A‐L/Evi9a and Bcl11A‐S/Evi9c could be found in extranuclear locations. Double staining with the synaptic marker synaptophysin indicated a synaptic distribution of Bcl11A/Evi9/CTIP1. Postsynaptic density was also biochemically purified and subjected to immunoblotting using Bcl11A/Evi9/CTIP1 antibodies. The results showed that Bcl11A‐L/Evi9a was enriched in the PSD I and PSD II fractions. In contrast, only a trace amount of Bcl11A‐S was detected in PSD fractions. Our study also indicated that a fraction of Bcl11A/Evi9/CTIP1 was present in the cytoplasm, even at synapses. To regulate gene expression in the nuclei, nuclear translocation of Bcl11A/Evi9/CTIP1 may be one of the mechanisms controlling neuronal Bcl11A/Evi9/CTIP1 function. © 2007 Wiley‐Liss, Inc.
Activation of endogenous neural stem cells in the adult human brain following subarachnoid hemorrhage
Authors: Sgubin D. , Aztiria E. , Perin A. , Longatti P. , Leanza G.
Published: April 2007

In the adult human brain, the presence of neural stem cells has been documented in the subgranular layer of the dentate gyrus of the hippocampus and in the subventricular zone of the lateral ventricles. Neurogenesis has also been reported in rodent models of ischemic stroke, traumatic brain injury, epileptic seizures, and intracerebral or subarachnoid hemorrhage. However, only sparse information is available about the occurrence of neurogenesis in the human brain under similar pathological conditions. In the present report, we describe neural progenitor cell proliferation in the brain of patients suffering from subarachnoid hemorrhage (SAH) resulting from ruptured aneurysm. Ten cerebral samples from both SAH and control patients obtained, respectively, during aneurysm clipping and deep brain tumor removal were analyzed by reverse transcription followed by polymerase chain reaction (RT‐PCR) and/or immunohistochemistry (IHC). In tissue specimens from SAH patients, RT‐PCR and IHC revealed the expression of a variety of markers consistent with CNS progenitor cells, including nestin, vimentin, SOX‐2, and Musashi1 and ‐2. In the same specimens, double immunohistochemistry followed by confocal analysis revealed that Musashi2 consistently colocalized with the proliferation marker Ki67. By contrast, no such gene or protein expression profiles were detected in any of the control specimens. Thus, activation of neural progenitor cell proliferation may occur in adult human brain following subarachnoid hemorrhage, possibly contributing to the promotion of spontaneous recovery, in this pathological condition. © 2007 Wiley‐Liss, Inc.
Evaluation of pear firmness by dynamic characteristics of drop impact
Authors: Wang Jun , Ying Tiejing , Cheng Kuchuan
Published: April 2007

The dynamic resonance frequency based on the dynamic frequency response of pear dropped onto a flat plate was determined by impacted orientation, drop height, material of impact surface, pear firmness and pear mass. Response signals in time domain were detected, and transformed into frequency domain (by means of fast Fourier transform). The dominant frequency (the response magnitude is the greatest) was significantly affected by pear firmness and pear mass. Impact orientation, drop height and impact surface material did not significantly affect the dominant frequency. The dominant frequency increased with increase of pear firmness, and decreased with increasing pear mass. Good relationships were obtained between dominant frequency and Magness–Taylor or pear mass (r2 = 0.716 and 0.771), and the stiffness index (Sc = f2m2/3) regressed on Magness–Taylor firmness had better relationship also r = 0.819). Pear firmness can be predicted by the drop impact method. Copyright © 2007 Society of Chemical Industry
Analysis of characteristic aroma of fungal fermented Fuzhuan brick‐tea by gas chromatography/mass spectrophotometry
Authors: Xu Xiangqun , Mo Haizhen , Yan Mingchao , Zhu Yang
Published: April 2007

Fuzhuan brick‐tea is a popular fermented Chinese dark tea because of its typical fungal aroma. Fungal growth during the production process is the key step in achieving the unique colour, aroma and taste of Fuzhuan brick‐tea. To further understand the generation of the characteristic aroma, changes in the main volatile compounds of Fuzhuan brick‐tea during the fungal growth stage were studied by gas chromatography/mass spectrophotometry. The results showed that the content of volatile compounds, especially aldehyde compounds with stale aroma such as (E)‐2‐pentenal, (E)‐2‐hexenal, 1‐penten‐3‐ol, (E, E)‐2,4‐heptadienal and (E, Z)‐2,4‐heptadienal, increased significantly in fermented tea samples. The concentration of terpene alcohols with flower aroma also increased notably during the fermentation process. The compounds with stale and flower aromas in combination with some volatile components of the raw material contributed to the characteristic ‘fungal/flower’ aroma of Fuzhuan brick‐tea. Microbial metabolism during the fermentation process probably played the key role in the generation of characteristic aromatic compounds of Fuzhuan brick‐tea. Copyright © 2007 Society of Chemical Industry
Simultaneous lactic acid and xylitol production from vine trimming wastes
Authors: Rivas Beatriz , Torrado Ana , Rivas Sandra , Moldes Ana Belén , Domínguez José Manuel
Published: April 2007

Hemicellulosic hydrolyzates from vineshoot trimmings obtained by dilute sulfuric acid hydrolysis were evaluated for xylitol production by Debaryomyces hansenii NRRL Y‐7426. Bioconversion was not efficient, however, since a mixture of products (mainly ethanol) was achieved. Taking into account that hexoses (such as glucose or mannose) can inhibit xylose metabolism by repression and inactivation of the xylose transport system or catabolic enzymes and that these hemicellulosic hydrolyzates are characterized by a high glucose concentration, a novel technology was developed, sequentially transforming glucose into lactic acid by Lactobacillus rhamnosus followed by fermentation of xylose into xylitol by Debaryomyces hansenii after L. rhamnosus removal by microfiltration. Optimal conditions were achieved using detoxified concentrated hemicellulosic hydrolyzates, after CaCO3 addition in both stages of fermentation and using nitrogen purges after sampling in order to reduce the oxygen dissolved. Under these conditions 31.5 g lactic acid L−1 (QLA = 1.312 g L−1 h−1 and YLA/S = 0.93 g g−1) and 27.5 g xylitol L−1 (QXylitol = 0.458 g L−1 h−1 and YXylitol/S = 0.53 g g−1) were produced. Finally, lactic acid was selectively recovered using the resin Amberlite IRA 400 (0.0374 g of lactic acid g−1 of dry resin), allowing a further recovery of xylitol by sequential stages of adsorption, concentration, ethanol precipitation, concentration and crystallization to obtain food‐grade xylitol according to a developed process. Copyright © 2007 Society of Chemical Industry
Barriers to rehabilitation following surgery for primary breast cancer
Authors: Cheville Andrea L. , Tchou Julia
Published: April 2007

Surgery is a mainstay of primary breast cancer therapy. Alterations in surgical technique have reduced normal tissue injury, yet pain and functional compromise continue to occur following treatment. A tenuous evidence base bolstered by considerable expert opinion suggests that early intervention with conventional rehabilitative modalities can reduce surgery‐associated pain and dysfunction. Barriers to the timely rehabilitation of functionally morbid sequelae are discussed at length in this article. Barriers arise from a wide range of academic, human, logistic, and financial sources. Despite obstacles, expeditious and effective post‐surgical rehabilitation is being regularly delivered to breast cancer patients at many institutions. This experience has given rise to anecdotal information on the management of common sequelae that may undermine function. The epidemiology, pathophysiology, and management of these sequelae are outlined in this article with an emphasis on the caliber of supporting evidence. Myofascial dysfunction, axillary web syndrome, frozen shoulder, lymphostasis, post‐mastectomy syndrome, and donor site morbidity following breast reconstruction are addressed. A critical need for more definitive evidence to guide patient management characterizes the current treatment algorithms for surgical sequelae. Surg. Oncol. 95:409–418. © 2007 Wiley‐Liss, Inc.
Flexible UV light guiding system for intraocular laser microsurgery
Authors: Schastak Stanislaw , Yafai Yousef , Yasukawa Tsutomu , Wang Yu‐Sheng , Hillrichs Georg , Wiedemann Peter
Published: April 2007

Background and Objective

Until now, UV lasers could not be applied to vitreoretinal surgery because of the absence of a practical beam guiding system. A flexible, freely mobile hollow core waveguide, capable of delivering UV laser light, was recently developed. We evaluated the feasibility of this UV laser guiding system for vitreoretinal surgery in enucleated porcine and rabbit eyes and in vivo on rabbit retina.

Materials and Methods

193‐nm argon fluoride (ArF) excimer laser and a 5th harmonic Nd:YAG laser with the wavelength of 213 nm were used as a light source. A hollow core waveguide was connected to a handpiece with a 20‐gauge endoprobe as an instrument for vitreoretinal surgery.

Results

Cutting of the retina was possible only with contact technique. With a selected repetition rate of 20 Hz, sharp, full‐depth dissection of porcine retinas was achieved only with 1.0 J/cm2. With the repetition rate of 50 Hz, even 0.05 J/cm2 could incise the total thickness of rabbit retina with no histological damage of the underlying retinal pigment epithelium. The ease in using the instrument for vitreoretinal surgery was confirmed by the in vivo experiment.

Conclusion

This study revealed the potential use of the new type of the UV laser scalpel, connected to a hollow core waveguide, to perform precise, “cold,” and tractionless cutting during vitreoretinal surgery. Lasers Surg. Med. 39: 353–357, 2007. © 2007 Wiley‐Liss, Inc.
Prospective direct comparison study of fractional resurfacing using different fluences and densities for skin rejuvenation in Asians
Authors: Kono Taro , Chan Henry H. , Groff William Frederick , Manstein Dieter , Sakurai Hiroyuki , Takeuchi Masaki , Yamaki Takashi , Soejima Kazutaka , Nozaki Motohiro
Published: April 2007

Background and Objective

Fractional resurfacing is a new concept of cutaneous remodeling whereby laser‐induced zones of microthermal injury are surrounded by normal untreated tissue. The aim of this study is to compare the efficacy and complications of Fraxel laser treatment when using different fluences and density settings.

Study Design/Materials and Methods

Thirty female Asian patients were enrolled in the study. Group 1 (n = 10); half of the face was treated with eight passes at 125 MTZ/cm2 at an energy setting of 8 mJ. The other half of the face was treated with eight passes at 250 MTZ/cm2 at an energy setting of 8 mJ. Group 2 (n = 10); half of the face was treated with eight passes at 125 MTZ/cm2 at an energy setting of 8 mJ. The other half of the face was treated with eight passes at 125 MTZ/cm2 at an energy setting of 16 mJ. Group 3 (n = 10); half of the face was treated with eight passes at 125 MTZ/cm2 at an energy setting of 16 mJ. The other half of the face was treated with eight passes at 250 MTZ/cm2 at an energy setting of 8 mJ. Ice pack cooling was used during and after laser treatment. The patients were evaluated for clinical efficacy and treatment‐related side effects.

Results

Pain, erythema, and swelling were observed to be significantly more evident or persisted longer in patients treated with higher densities and fluences (P<0.01). Patient satisfaction is significantly greater in patients treated with higher fluences (P<0.05), but not in patients treated with higher densities. Hyperpigmentation was observed in two patients.

Conclusion

Increased density was more likely to produce swelling, redness, and hyperpigmentation when compared to increased energy. Patient satisfaction is significantly higher when their skin is treated with high fluences, but not when patients' skin is treated with high densities. Lasers Surg. Med. 39: 311–314, 2007. © 2007 Wiley‐Liss, Inc.
Flashlamp pulsed‐dye laser suppressed TGF‐β1 expression and proliferation in cultured keloid fibroblasts is mediated by MAPK pathway
Authors: Kuo Yur‐Ren , Wu Wen‐Sheng , Wang Feng‐Sheng
Published: April 2007

Background and Objectives

Our previous clinical study indicated that transforming growth factor‐β1 (TGF‐β1) and mitogen‐activated protein kinases (MAPK) are both involved in keloid regression following flashlamp pulsed‐dye laser (PDL). To further characterize of this involvement, this work examined whether PDL suppression of TGF‐β1 expression was mediated through MAPK pathway in cultured keloid fibroblasts (KF).

Study Design/Materials and Methods

Primary culture of KF harvested from keloid patients received various dosages of PDL treatment in 585‐nm wavelength. TGF‐β1 expressions in KF following various dosages of PDL were assessed. Additionally, MAPK pathway activities were studied using the PD98059 (an ERK inhibitor), SB203580 (a p38 kinase inhibitor), and SP600125 (a JNK inhibitor), to determine the role in keloid following PDL treatment. Activator protein‐1 (AP‐1), a transcription factor of TGF‐β, was analyzed by electrophoretic mobility shift assay (EMSA). Phosphorylated c‐Jun, one of the components of AP‐1, was also detected.

Results

The observation results demonstrated that optimal dosages of PDL significantly suppressed KF proliferation and TGF‐β1 expression. EMSA study identified PDL downregulation of super‐shift of AP‐1. Three subtypes of MAPK cascades were augmented between 30 minutes and 4 hours following PDL treatment, particularly phosphorylation of ERK1/2 and p38. Pre‐treatment with PD98059, SB203580, but not SP600125, markedly inhibited the downregulating effects of TGF‐β1 and phosphorylated c‐Jun expression following PDL treatment.

Conclusion

PDL induced keloid regression is mediated by triggering MAPK cascades and blockade of AP‐1 transcription and TGF‐β expression. Modulation of TGF‐β and MAPK interaction in keloids may provide specific targets for therapeutic intervention. Lasers Surg. Med. 39: 358–364, 2007. © 2007 Wiley‐Liss, Inc.
Styrene–Ferrocenyldimethylsilane–Methyl Methacrylate Triblock Copolymers: Synthesis and Phase Morphology
Authors: Kloninger Christian , Rehahn Matthias
Published: April 2007

Triblock copolymers were synthesized from styrene (S), dimethylsilaferrocenophane (FS), and methyl methacrylate (MMA) via sequential anionic polymerization, taking advantage of the dimethylsilacyclobutane‐mediated endcapping of the living PS‐b‐PFS precursors. Well‐defined materials were obtained, having molecular weights of around 100 000 g · mol−1and polydispersity indices of below 1.1. First investigations of the microphase behavior show that the materials selforganize in bulk morphologies where PMMA is the matrix while PS forms either spheres or cylinders. The central short PFS block forms either droplets or cylinders, which are placed at the surface of the PS domains.

magnified image
Darstellungsformeln erster Näherung für GREENsche Funktionen von Wellengleichungen in RIEMANNscher Raum‐Zeit
Authors: John R. W.
Published: April 2007

By applying perturbation theory to the construction scheme for GREEN's functions in a curved RIEMANNian space‐time due to HADAMARD, explicit formulae for scalar and vector GREEN's functions in the first post‐MINKOWSKIan approximation are derived. The two‐point functions entering into the construction are represented by integrals of the first‐order metric terms and their derivatives taken along the straight line joining the two points. Using these expressions, one obtains explicit conditions for the validity of HUYGEN's principle for the wave equations in the first approximation.
SCHWARZSCHILD‐FRIEDMANNsche Lösungen der EINSTEINschen Feldgleichungen
Authors: Dautcourt G.
Published: April 2007

Es werden „Friedmonenlösungen”︁ der EINSTEINschen Feldgleichungen untersucht, bei denen eine äußere SCHWARZSCHILD‐Lösung an einen fast vollständig geschlossenen FRIEDMANN‐Kosmos angeschlossen ist. Die Diskussion zeigt, daß auf der Anschlußfläche keine Flächenbelegungen auftreten.
RAFT Inverse Miniemulsion Polymerization of Acrylamide
Authors: Qi Genggeng , Jones Christopher W , Schork F. Joseph
Published: April 2007

RAFT inverse miniemulsion polymerization is demonstrated for the first time as an alternate way to synthesize hydrophilic polymer latexes. The kinetic behavior of inverse RAFT miniemulsion polymerization of acrylamide is similar to that observed in aqueous RAFT solution polymerization. A water‐soluble initiator provides better control than a lipophilic initiator in inverse RAFT miniemulsion polymerization under the conditions used here.

magnified image
Chiral Polymer Helices with Shape Identical to Previously Reported Helical Calcium Carbonate Morphologies
Authors: Glaab Fabian , Kellermeier Matthias , Kunz Werner
Published: April 2007

Helices with highly ordered substructures were found sporadically during precipitation of self‐assembled silica‐barium carbonate “biomorphs”. Identical morphologies are already known and cited in the literature as helical calcite structures, formed by the influence of chiral phosphoserine copolypeptides. Yamamoto et al. claim that the handedness of the helices can be tuned by the chirality of the amino acids in the phosphoserine copolypeptides. Optical and scanning electron microscopy, energy‐dispersive X‐ray analysis, thermogravimetry, as well as proton and carbon nuclear magnetic resonance were performed on selected twisted ribbons, proving that these helical superstructures—in shape identical to the helical calcite morphologies reported by Yamamoto et al.—do not consist of inorganic material but of an organic polymer, representing plastic abrasion caused by scratching glass pipettes along plastic surfaces.

magnified image
Azobenzene Liquid‐Crystalline Polymer for Optical Switching of Grating Waveguide Couplers with a Flat Surface
Authors: Bang Chong‐Uk , Shishido Atsushi , Ikeda Tomiki
Published: April 2007

Grating waveguide couplers with a flat surface were fabricated in an azobenzene liquid‐crystalline polymer film by holographic lithography using Ar+ laser beams at 488 nm. When a probe beam at 633 nm was incident to one grating of a grating waveguide coupler, the beam propagated in the waveguide and an output beam came out from the other grating with the throughput coupling efficiency of ≈5%. Upon irradiation of the film between two gratings with UV light to cause trans–cis photoisomerization of the azobenzene moiety, the intensity of the output beam was repeatedly switched. It was found that the alternating irradiation at 366 and 436 nm induced reversible changes in the intensity of the guided probe beam.

magnified image
Biased AC Electrospinning of Aligned Polymer Nanofibers
Authors: Sarkar Soumayajit , Deevi Seetharama , Tepper Gary
Published: April 2007

A new method is reported for minimizing the inherent fiber instability in the electrospinning process. The method, dubbed “biased AC electrospinning”, employs a combination of DC and AC potentials and results in highly‐aligned mats of polymer or composite polymer fibers. The relationship between specific processing variables such as the AC frequency and the magnitude of the DC offset was investigated and related to the resulting fiber stability and uniformity. For optimum fiber stability, the AC frequency must fall within a relatively narrow range. The upper and lower frequency limits were measured for a small group of polymers and polymer composites and were qualitatively related to solution properties and processing variables. Potential applications of well‐ordered nanofiber materials include tissue engineering, filtration, drug delivery, and microelectronics.

magnified image
Macromol. Rapid Commun. 9/2007
Authors: Norakankorn Chaiwat , Pan Qinmin , Rempel Garry L. , Kiatkamjornwong Suda
Published: April 2007

Cover: The cover picture describes a new approach which enables controllable formation of nano polymer particles. The resultant particles could contain only one or two polymer chains, i.e. they are molecular bricks with potential important applications. Further details can be found in the article by C. Norakankorn, Q. Pan,* G. L. Rempel,* and S. Kiatkamjornwong on page 1029.
RF refocused echoes of J‐coupled spin systems: Effects on RARE‐based spectroscopic imaging
Authors: Mayer Dirk , Dreher Wolfgang , Leibfritz Dieter , Spielman Daniel M.
Published: April 2007

A numerical simulation tool was developed to calculate the echo amplitudes of J‐coupled resonances within a series of radiofrequency (RF) refocused echoes. The signal modulation due to J‐coupling in rapid acquisition with relaxation enhancement (RARE) is suppressed only when the inverse of the pulse interval (τ) is large compared to both the chemical shift (CS) difference (Δδ) of the coupled spins and the coupling constant. In contrast, the echo amplitudes in ultrafast low‐flip‐angle RARE (U‐FLARE) oscillate around a quasi‐steady‐state value that is greater than zero (neglecting relaxation and diffusion) even when Δδ > 1/τ. The flip‐angle distribution over the measured slice caused by the use of Gaussian‐shape slice‐selective refocusing pulses further reduces the echo oscillations. When the pulse interval falls short of the fast pulse rate regime, spectroscopic U‐FLARE provides an improved spatial impulse response in the phase‐encoding (PE) direction compared to spectroscopic RARE. Magn Reson Med 57:967–971, 2007. © 2007 Wiley‐Liss, Inc.
Perfusion MRI with radial acquisition for arterial input function assessment
Authors: Kholmovski Eugene G. , DiBella Edward V.R.
Published: April 2007

Quantification of myocardial perfusion critically depends on accurate arterial input function (AIF) and tissue enhancement curves (TECs). Except at low doses, the AIF is inaccurate because of the long saturation recovery time (SRT) of the pulse sequence. The choice of dose and SRT involves a trade‐off between the accuracy of the AIF and the signal‐to‐noise ratio (SNR) of the TEC. Recent methods to resolve this trade‐off are based on the acquisition of two data sets: one to accurately estimate the AIF, and one to find the high‐SNR TEC. With radial k‐space sampling, a set of images with varied SRTs can be reconstructed from the same data set, allowing an accurate assessment of the AIF and TECs, and their conversion to contrast agent (CA) concentration. This study demonstrates the feasibility of using a radial acquisition for quantitative myocardial perfusion imaging. Magn Reson Med 57:821–827, 2007. © 2007 Wiley‐Liss, Inc.
Carotid plaque classification: Defining the certainty with which plaque components can be differentiated
Authors: Ronen Raphael R. , Clarke Sharon E. , Hammond Robert R. , Rutt Brian K.
Published: April 2007

Multicontrast‐weighted MRI has the potential to become a powerful tool for assessment of atherosclerotic plaque. However, similarities in MR properties across plaque components limit the certainty with which these components can be differentiated. An understanding of MRI's underlying limitations in distinguishing atherosclerotic plaque components, and optimization of key parameters (including the set of components investigated and contrast weightings used) are required. In this study we analyzed endarterectomy specimens using multicontrast MRI and compared the results with matching histological findings to determine the probability of error, an unbiased measure of the underlying error caused by similarity in the spectral characteristics of components. The total error was >40% when five distinct components were investigated, but this was halved when components with similar functions and intensities were grouped together. When three contrast weightings were used to view plaque, diffusion‐weighted imaging (DWI) proved valuable for separating hemorrhage from necrotic core, and “hemorrhage + necrotic” from “loose connective tissue + fibrous tissue.” A two‐way interaction between contrast weightings and components demonstrated that the value of a contrast can be exploited or marginalized depending on the choice of contrast weightings used. Magn Reson Med 57:874–880, 2007. © 2007 Wiley‐Liss, Inc.
Reduction of transmitter B1 inhomogeneity with transmit SENSE slice‐select pulses
Authors: Zhang Zhenghui , Yip Chun‐Yu , Grissom William , Noll Douglas C. , Boada Fernando E. , Stenger V. Andrew
Published: April 2007

Parallel transmitter techniques are a promising approach for reducing transmitter B1 inhomogeneity due to the potential for adjusting the spatial excitation profile with independent RF pulses. These techniques may be further improved with transmit sensitivity encoding (SENSE) methods because the sensitivity information in pulse design provides an excitation that is inherently compensated for transmitter B1 inhomogeneity. This paper presents a proof of this concept using transmit SENSE 3D tailored RF pulses designed for small flip angles. An eight‐channel receiver coil was used to mimic parallel transmission for brain imaging at 3T. The transmit SENSE pulses were based on the fast‐kz design and produced 5‐mm‐thick slices at a flip angle of 30° with only a 4.3‐ms pulse length. It was found that the transmit SENSE pulses produced more homogeneous images than those obtained from the complex sum of images from all receivers excited with a standard RF pulse. Magn Reson Med 57:842–847, 2007. © 2007 Wiley‐Liss, Inc.
MRI in mouse developmental biology
Authors: Turnbull Daniel H. , Mori Susumu
Published: April 2007

Mice are used in many studies to determine the role of genetic and molecular factors in mammalian development and human congenital diseases. MRI has emerged as a major method for analyzing mutant and transgenic phenotypes in developing mice, at both embryonic and neonatal stages. Progress in this area is reviewed, with emphasis on the use of MRI to analyze cardiovascular and neural development in mice. Comparisons are made with other imaging technologies, including optical and ultrasound imaging, discussing the potential strengths and weaknesses of MRI and identifying the future challenges for MRI in mouse developmental biology. Copyright © 2007 John Wiley & Sons, Ltd.
Oxidative stress and DNA hypermethylation status in renal cell carcinoma arising in patients on dialysis
Authors: Hori Y , Oda Y , Kiyoshima K , Yamada Y , Nakashima Y , Naito S , Tsuneyoshi M
Published: April 2007

Renal cell carcinoma (RCC) is more frequently observed in patients on dialysis than in patients with normal renal function. However, the mechanism underlying carcinogenesis in RCC patients on dialysis is still unclear. We hypothesized that oxidative stress affects patients on dialysis and generates new neoplasms, and therefore analysed the correlation between the influences of various markers of oxidative stress and carcinogenesis in those patients. We evaluated the immunohistochemical expression of oxidative stress markers, such as iNOS, 8‐OHdG, and COX‐2 in 42 cases on dialysis and 51 cases with normal renal function as a control. The methylation status of p16INK4a, p14ARF, VHL, and RASSF1A was analysed together with clinicopathological factors. Histologically, the papillary type was observed more frequently in dialysis RCC than in sporadic RCC. Immunohistochemically, overexpression of iNOS (p < 0.0001) and COX‐2 (p = 0.0002) was more frequently observed in dialysis RCC. Furthermore, the 8‐OHdG labelling index was significantly higher in dialysis RCC than in sporadic RCC. Hypermethylation of p16INK4a was more frequently found in dialysis RCC (p < 0.05). However, no significant correlations between oxidative stress markers and DNA hypermethylation status were observed. The overexpression of iNOS, COX‐2, and 8‐OHdG in dialysis RCC suggests that patients on dialysis are affected by oxidative stress and that this effect plays an important role in the genesis of dialysis RCC. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
CNS complications in children receiving chemotherapy or hematopoietic stem cell transplantation: Retrospective analysis and clinical study of survivors
Authors: Schmidt Katrin , Schulz Ansgar Stephan , Debatin Klaus‐Michael , Friedrich Wilhelm , Classen Carl Friedrich
Published: April 2007

Background

Clinical studies analyzing CNS complications in pediatric oncology systematically are rare.

Procedure

In a single center retrospective analysis, CNS complications in 950 subsequent pediatric patients treated between 1992 and 2004 by chemotherapy or hematopoietic stem cell transplantation (HSCT) were studied. Forty‐six patients had pre‐existing CNS diseases and were excluded. Out of the 904 remaining, 76 (8.4%) had 82 CNS complications.

Results

The most common manifestations were seizures (in 50.6% of the CNS episodes), altered states of consciousness, and motor deficits (in 47.5% of the episodes each). CNS complications were caused by infections (26.8%), toxicity (25.6%), neoplasma (13.4%), vascular (10.9%), and metabolic disturbances (8.5%). In 14.6%, the mechanism remained unclear. Patients (23.7%) died from the CNS event. Neoplastic disorders had the worst (50%) while metabolic the best (0% mortality) prognosis. Imaging techniques were the most effective diagnostic measures, followed by laboratory analysis, clinical examination, and CSF analysis. A neuro‐psychological (CBCL, CFT‐1/−20—testing) examination could be done in 21 of 32 long‐term survivors. Seven had a major, 3 minor neurological impairment, 11 were normal in all tests.

Conclusions

These data show that there is not one typical CNS complication, but a wide variety. There is no close connection between either underlying disease or symptoms and cause of the complication. Prognosis is variable. About two thirds of the long‐term survivors could lead a normal life. Pediatr Blood Cancer 2008;50:331–336. © 2007 Wiley‐Liss, Inc.
Prenatal detection of congenital bilateral cataract leading to the diagnosis of Nance‐Horan syndrome in the extended family
Authors: Reches Adi , Yaron Yuval , Burdon Kathryn , Crystal‐Shalit Ornit , Kidron Dvora , Malcov Mira , Tepper Ron
Published: April 2007

Objectives

To describe a family in which it was possible to perform prenatal diagnosis of Nance‐Horan Syndrome (NHS).

Methods

The fetus was evaluated by 2nd trimester ultrasound. The family underwent genetic counseling and ophthalmologic evaluation. The NHS gene was sequenced.

Results

Ultrasound demonstrated fetal bilateral congenital cataract. Clinical evaluation revealed other family members with cataract, leading to the diagnosis of NHS in the family. Sequencing confirmed a frameshift mutation (3908del11bp) in the NHS gene.

Conclusion

Evaluation of prenatally diagnosed congenital cataract should include a multidisciplinary approach, combining experience and input from sonographer, clinical geneticist, ophthalmologist, and molecular geneticist Copyright © 2007 John Wiley & Sons, Ltd.